Rapamycin And Cisplatin In Breast Cancers

Rapamycin And Cisplatin In Breast Cancers Recent gene expression profiling has identified five breast cancer subtypes, of which the basal-like breast cancers are the most aggressive and possess serious clinical challenges as there are currently no targeted therapies available. Although there is increasing evidence that these tumors confer specific sensitivity to cisplatin, its success is often compromised due to its dose-limiting nephrotoxicity and development of drug resistance. To overcome this limitation, our focus is to maximize the benefits associated with cisplatin therapy through drug combination strategies. Using a well-validated kinase inhibitors library, we showed that inhibition of mTOR, TGFà ¯Ã‚ Ã‚ ¢RI, NFà ¯Ã‚ Ã‚ «B, PI3K/AKT and MAPK pathway sensitized the basal-like MDA-MB-468 cells to cisplatin treatment. Further evaluation demonstrated that combination of mTOR inhibitor, rapamycin, and cisplatin generated significant drug synergism specifically in basal-like cells (MDA-MB-468, MDA-MB-231 and HCC1937). Th ese synergistic effects were not observed in the luminal-like T47D and MCF-7 cells. We further showed that the synergistic effects of rapamycin and cisplatin is mediated through p73. Treatment of rapamycin induced p73 upregulation and synergized cisplatin activity through activation of the p73 pathway. Depletion of endogenous p73 in basal-like cells abolished these synergistic effects suggesting that p73 is required for the rapamycin and cisplatin synergism. In conclusion, combination of mTOR inhibitors and cisplatin may be a useful therapeutic strategy in basal-like breast cancers. INTRODUCTION Recent identification of novel breast cancer subtypes with distinct biological features promises a more specific, effective and less toxic therapies to the patients. Through gene profiling, breast cancer can be categorized into five different subtypes with distinct clinical outcome. The five major subtypes of breast cancer are luminal A, luminal B, human epidermal growth factor receptor-2 (HER2) overexpressing, normal-like and basal-like breast cancer [1, 2]. Of particular important is the basal-like breast cancer which accounts for 15-20% of breast cancers overall and confers a remarkably poor prognosis compared to other subtypes. Majority of basal-like breast cancers exhibit a triple-negative phenotype, characterized by the lack of expression of estrogen receptor (ER), progesterone receptor (PR) or HER2 amplification, and often have high frequency of p53 mutation [3, 4]. Due to the lack of expression of these receptors (ER, PR and HER2), patients with basal-like breast cancers usua lly do not response to hormonal therapy, Herceptin or chemotherapy [5, 6]. As a consequence, the mortality rate of basal-like breast cancer is relatively high in comparison with the non-basal subtype [1]. Numerous clinical studies are currently ongoing to identify novel therapy for treatment of basal-like breast cancers. These include the use of specific targeted therapeutic agents (e.g. Cetuximab, Dasatinib, Bevacizumab, Abraxane and Erlotinib) or conventional chemotherapeutics agents (e.g. cisplatin, doxorubicin, and paclitaxel), either as single agent or in combination, as first line therapy for basal-like breast cancers [7-9]. Cisplatin, a chemotherapeutic agent not commonly used for breast cancer, come to light in the management of basal-like breast cancer on account of evidence that breast cancer cells with basal-like phenotype confer a selective sensitivity towards cisplatin as compared to other chemotherapeutic agents. A variety of evidence suggests that basal-like breast cancers may share defects in BRCA1-associated pathways, of which DNA repair mechanism has been compromised [10]. Indeed, recent clinical studies have demonstrated the clear advantage of cisplatin in treatment of basal-like breast cancer compared to other chemotherapeutic agents [11, 12]. Nevertheless, dose-limiting toxicity including nephrotoxicity, neurotoxicity and ototoxicity have withold the wide-spread use of cisplatin in treating breast cancers in the clinic. To address this problem, we developed a high-throughput screening assay to rapidly identify new therapeutic agents that could synergize the antitumor effects of cisplatin in basal-like breast cancers. Through the use of a small chemical library that targets some of the most relevant oncogenic pathways in basal-like breast cancer, we show that inhibition of mTOR by rapamycin incurred a specific synergistic effect with cisplatin in basal-like breast cancer cells. This synergistic effect is mediated in part through the induction and activation of p73 in the presence of rapamycin and cisplatin, respectively. Together, our findings demonstrate evidence of a synergistic relation between rapamycin and cisplatin in both inhibition of cell growth and induction of apoptosis. This suggests that rapamycin and cisplatin may be a rational combination of a targeted therapy for the refractory basal-like breast cancers. Materials and Methods Cell lines and cell culture The human breast carcinoma cell lines MCF-7, T47D, MDA-MB-231, MDA-MB-468 and HCC1937 were obtained from the American Type Culture Collection (Manassas, VA) and maintained in RPMI 1640 medium containing 10% fetal bovine serum (FBS), 100 IU/ml penicillin and 100 ÃŽÂ ¼g/ml streptomycin (Sigma-Aldrich, St. Louis, MO, USA) at 37 °C with 5% CO2. MTT cell proliferation assay Dose-response curves and IC50 values were determined using the methyl thiazolyl tetrazolium (MTT) cell viability assay as described previously [4, 13]. Cells were seeded into 96-well plates for 24 hours at a density of 5 ÃÆ'- 103 cells/well. Serial drug dilutions were prepared in medium immediately before each assay, and viable cell masses following 3 days of drug exposure were determined by cell-mediated MTT reduction. Cell growth as well as drug activity was determined by measuring absorbance at 550 nm using an Anthos systems plate reader. Construction of IC50 mean graph The IC50 mean graph was constructed as defined by the Developmental Therapeutics Program of the National Cancer Institute (http://dtp.nci.nih.gov). The mean graph consists of positive (more sensitive) and negative (less sensitive) delta values, generated from a set of IC50 values by using a three-step calculation. The IC50 values for each of cell line against the tested compound were converted to log(IC50) values. For each tested compound, the log(IC50) values are averaged. Finally, the individual IC50 value is then subtracted from the average to generate the delta value. Positive delta values project to the right of the vertical line and represent cellular sensitivities to the test agent that exceed the mean. Negative values project to the left and represent cell line sensitivities to the test agent that are less than the average value. Library screening The Inhibitor Select„ ¢ chemical library which consists of 160 well-characterized, cell-permeable inhibitors was purchased from EMD Chemicals, USA. MDA-MB-468 cells at the logarithmic phase of growth were seeded into 96-well plate at a density of 5 ÃÆ'- 103 cells/well. Each compound was added to a final concentration of 10  µM in the absence or presence of 1  µM cisplatin. Plates were incubated for 72h at 37 °C. Cell proliferation was examined using MTT assay as described previously. Combination treatments that induce growth inhibition higher than those of the same doses used alone (p Drug interaction analysis Drug combination analysis was performed by using the method as described by Chou and Talalay [14]. Briefly, cells were seeded at 5 ÃÆ'- 103 cells/well in 96-well plates and treated with various concentrations of cisplatin and compound alone or in combination for 72h. Cell proliferation was measured in each well by MTT assay. Multiple drug dose-effect calculations and the combination index plots were generated using Calcusyn software (Biosoft, Cambridge, UK). Combination index, CI 1 indicate synergism, additive effect and antagonism, respectively. Apoptosis assays Quantitation of apoptosis by annexin V/PI staining was performed as described previously [3, 4]. Briefly, both floating and attached cells were collected 72h after drug treatments. Apoptotic cell death was determined using the BD ApoAlert annexin V-FITC Apoptosis Kit (BD Biosciences, USA) according to the manufacturers instructions, and cells were analyzed on a FACSCalibur flow cytometer using CellQuest Pro software (version 5.1.1; BD Biosciences, USA). Quantitative PCR (qPCR) analysis Total RNA from cells was extracted using Qiagen RNA isolation kit (Qiagen, Valencia, CA, USA) according to the manufacturers protocol. First-strand cDNA was synthesized from total RNA using random hexamer primers and the SuperScript II system for RT-PCR (Invitrogen, Carlsbad, USA). Gene expression levels were measured by qPCR using the iQ SYBR Green Supermix reagent and an Biorad iQ5 real-time PCR detector system (Bio-Rad, Richmond, CA, USA). Data analysis was performed using Opticon Monitor Analysis Software V1.08. The expression of each gene was normalized to ÃŽÂ ²2M as a reference. The relative copy numbers were calculated from an 8-point standard curve generated from a 10-fold serial dilution of full-length cDNA constructs as described previously [3, 4]. Specific forward and reverse primer sequences are as follows : TAp73fwd, 5-GCACCACGTTTGAGCACCTCT-3; TAp73rev, 5- GCAGATTGAACTGGGCCATGA-3; ÃŽÂ ²2Mfwd, 5-AGCTGTGCTCGCGCTACTCTC-3; ÃŽÂ ²2Mrev, 5-CACACGGCAGGCATACTCATC-3; PUMA fwd PUMArev NOXAfwd NOXArev. The conditions for all QRT-PCR reactions were as follows: 3 minutes at 94 °C followed by 40 seconds at 94 °C, 40 seconds at 60 °C, and 25 seconds at 72 °C for 40 cycles. All PCR products were confirmed by the presence of a single peak upon melting curve analysis and by gel electrophoresis. No-template (water) reaction mixtures and no-RT mixtures were performed on all samples as negative controls. All experiments were performed in duplicate. Protein isolation and Western blot analysis Protein lysates from cells were extracted in ice-cold lysis buffer (0.75% NP-40, 1 mM DTT, and protease inhibitors in PBS). Total protein (25 ÃŽÂ ¼g) was subjected to SDS-PAGE followed by immunoblotting with the following antibodies: p73 (diluted 1:1,000, Ab-2; CalBiochem); pS6K (diluted 1:1,000; Cell Signaling Technology); S6K (diluted 1:1,000, Ab9645; Abcam); and ÃŽÂ ²-tubulin (diluted 1:2,500, D-10; Santa Cruz Biotechnology). Lentiviral production and infection The shRNA lentiviral constructs were created by transferring the U6 promoter-shRNA cassette into a lentiviral backbone, and high-titre lentiviral stocks were generated by co-transfection with packaging vectors into 293T cells as described previously [3, 4, 13]. The shRNA target sequences for TAp73 was 5-GGATTCCAGCATGGACGTCTT-3. The TAp73 targeted sequence is found within p73 exon 3. Therefore, this shRNA does not target ΆNp73 [4]. RESULTS Selective sensitivity of basal-like breast cancer toward cisplatin To gain an overview of the selectivity of chemotherapeutic agents for basal-like breast cancer cells, we compared their antiproliferative properties in a panel of basal-like and luminal-like breast cancer cell lines which has been validated previously through gene profiling [15]. All cells were treated with increasing concentrations of cisplatin, paclitaxel or doxorubicin for 72 hours and growth measured using the MTT assay. Figure 1A and B summarizes the results from these breast cancer cell lines in which basal-like breast cancer cells demonstrated selective sensitivity to cisplatin. This selectivity was absence in cells treated with paclitaxel or doxorubicin suggesting that basal-like breast cancer cells confer selective sensitivity towards cisplatin (Figure 1A, B and Supplement Table 1). Small chemical library screening identify rapamycin as synergistic agents for cisplatin Although cisplatin is currently one of the most used agents in the treatment of cancer, the use of cisplatin is hampered by its side effects, especially neurotoxicity, nephrotoxicity and rug resistance [16]. Hence, the present study was aimed to identify chemosensitizers that could synergize the effects of cisplatin for treatment of basal-like breast cancers. To identify small molecules that enhance sensitivity of basal-like breast cancer cells to cisplatin, a cell-based high-throughput screen was performed using MDA-MB-468 cell line and a small chemical library consisting of 160 well validated specific inhibitors. The screens were done in 96-well plates to which compounds were added at 10  µM, followed by cisplatin at 1  µM. Cell viability was measured 72 hours later by MTT assay. Each plate included controls of untreated cells, cells treated with compounds or cisplatin only, and cells treated with a combination of both agents. Combinations of the treatments that induced growth inhibition higher than those of the same doses used alone (p The molecules identified in this screen includes rapamycin, [3-(Pyridin-2-yl)-4-(4-quinonyl)]-1H-pyrazole (LY364947), 4-(3-Chloroanilino)-6,7-dimethoxyquinazoline (AG1478), (E)3-[(4-Methylphenyl)sulfonyl]-2-propenenitrile (BAY11-7082), 2-(4-Morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY294002) and 4-(4-Fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)1H-imidazole (SB203580). Structures of these compounds and their growth inhibitory effects were shown in Figure 2. The molecular target of these compounds was listed in Table 1. The 6 compounds identified are specific inhibitors of the mTOR, TGF-à ¯Ã‚ Ã‚ ¢, EGFR, NFà ¯Ã‚ Ã‚ «B PI3K/AKT and MAPK pathways which have been previously reported to be upregulated specifically in basal-like breast cancers [7, 17-20]. However, when tested for synergism with cisplatin at fixed concentration ratio, only rapamycin showed synergism when combined with cisplatin in MDA-MB-468 cells using the isobologram method that simulate the median-dose combination index (CI) [14]. The mean combination index at ED50, ED75, and ED90 of rapamycin (10:1 cisplatin:rapamycin) when combined with cisplatin was 0.52 à ¯Ã¢â‚¬Å¡Ã‚ ± 0.06, where combination index Specific synergistic effects of rapamycin and cisplatin in basal-like breast cancer cells Next, we sought to investigate if combination of cisplatin with rapamycin exhibit specific synergism in basal-like breast cancers by comparing their effects in a panel of breast cancer cell lines. The antiproliferative effect of treatment was evaluated using MTT assays and drug interaction was assessed by the isobologram method as described in the previous section. The results demonstrated that combination of rapamysin and cisplatin exhibited selective synergistic effects only in the basal-like MDA-MB-468, MDA-MB-231 and HCC1937 cells, but not in the luminal-like T47D or MCF-7 cells (Figure 3A and Table 2). To ensure that the lack of synergistic effects of rapamycin and cisplatin observed in luminal-like cells is not due the general lack of sensitivity of luminal-like cells to cisplatin per se, we compared the apoptotic effects of cisplatin and rapamycin alone or in combination in MDA-MB-231 and T47D cells using an equal potent dose of cisplatin (IC50 dose). Both cell lines exhibited similar amount of apoptosis following treatment with their respective IC50 dose of cisplatin. Interestingly, when both cell lines were treated with combination of cisplatin and rapamycin, synergistic effects were evidenced only in MDA-MB-231 cells but not in T47D cells. The potentiation effects of rapamycin observed in MDA-MB-231 cells were further enhanced by sequential treatment with rapamycin for 6 hours followed by cisplatin (data not shown). These results demonstrated that rapamycin is capable of sensitizing basal-like breast cancer cells to cisplatin, suggesting that the synergistic effects of rapamyc in and cisplatin may be mediated through a common pathway. Rapamycin sensitizes basal-like cells to cisplatin through p73 up regulation Previous study has shown that inhibition of mTOR by rapamycin up regulate p73 in breast cancer cells [21]. We and others have also demonstrated that p73 is overexpressed in a subset of triple-negative breast tumors and that p73 is required for cisplatin sensitivity in basal-like breast cancer cells [4]. On the basis of these findings, we ask if the synergistic effects of rapamycin and cisplatin combination could be explained by the activation of the p73 pathway. To test this notion, MDA-MB-231 cells were treated with 10  µM of cisplatin and 100 nM rapamycin alone or in combination for 48 hours. mTOR inhibition was confirmed using phospho-S6K as a marker of mTOR activity. Quantitation of the mRNA and protein expression of the TAp73 was performed using qPCR and immunoblotting, respectively. The results showed that treatment of rapamycin or cisplatin alone did not change the expression of TAp73 mRNA but induced significant up regulation of TAp73 protein expression in MDA-MB-231 cells (Figure 4A and B). Next, we evaluated the expression of the two potent pro-apoptotic BH3 only proteins, PUMA and NOXA, which has been identified as specific p73 target genes, using qPCR [22, 23]. As expected, treatment of cells with cisplatin for 48 hours induced mRNA expression of PUMA and NOXA in both MDA-MB-231 and MDA-MB-468 cells. Significant induction of PUMA and NOXA were also observed in MDA-MB-231 cells but not in MDA-MB-468 cells following treatment with rapamycin alone. When cells were treated with combination of cisplatin and rapamycin, the expression of PUMA and NOXA was further enhanced, corroborated with the massive induction of apoptosis as shown in Figure 3B. Together, these results suggest that rapamycin synergize cisplatin activity in basal-like cells through induction of p73 pathway. p73 is required for the synergistic effects of rapamycin and cisplatin in basal-like breast cancer cells To further evaluate whether p73 is the effector of the synergistic effects of rapamycin and cisplatin in basal-like breast cancer cells, we generated a series of isogenic cell lines that have been depleted for TAp73 by stably expressing a shRNA species that target specifically human TAp73. Unlike MDA-MB-231 cells which express one predominant TAp73 isoform (TAp73à ¯Ã‚ Ã‚ ¢) isoform, MDA-MB-468 cells express high levels of two p73 isoforms, TAp73à ¯Ã‚ Ã‚ ¡ and TAp73à ¯Ã‚ Ã‚ ¢ [21]. Figure 5A showed efficient knock-down of TAp73 isoforms in MDA-MB-231 and MDA-MB-468 cells. As expected, treatment of cisplatin alone induced significant amount of apoptosis in MDA-MB-468 vector control cells. This apoptotic effects were further enhanced in the presence of rapamycin, consistent with our previous observations (Figure 3B). In stark contrast, depletion of TAp73 not only reduced the amount of apoptosis following treatment of cisplatin alone but also completely abrogated the synergistic effects of rapamycin (Figure). This result is further supported by the isobologram analysis which showed a lack of synergism of rapamycin-cisplatin treatment in the TAp73 depleted cells. Together, these results suggest that TAp73 is required for the synergistic effects of rapamycin and cisplatin in basal-like breast cancers. DISCUSSION By gene profiling, breast cancers can be classified into 5 molecularly distinct subtypes: luminal A, luminal B, HER2+, basal-like and normal breast cancers. The basal-like subtype, which represents 15-20% of breast cancers, has been subjected to extensive investigation in recent years due to its association with poor patient survival [1, 2, 20, 24]. Unlike many breast cancers, patients diagnosed with basal-like breast cancers are not eligible for molecular targeted therapy that target ER (e.g. tamoxifen, aromatase inhibitors) or HER2 (e.g. Herceptin) as they do not express the estrogen receptor (ER) or progesterone receptor (PR), nor do they have amplified HER2 [1, 24]. The treatment option therefore is relied on aggressive conventional chemotherapies which have limited efficacy, many side effects and often high rate of relapse. Hence, development of an effective therapeutic strategy remains an important goal in the management of basal-like breast cancer. Several lines of evidence has suggested a link between basal-like breast cancers and BRCA1 deficiency [7, 25, 26]. In most cases, the clinical features and outcomes for women with sporadic basal-like breast cancers are broadly similar to those with BRCA1-related cancers including high tendency of developing high grade, high mitotic index tumors, shorter time of relapse, similar pattern of metastatic spread and cytogenetic changes associated with frequent loss of X-chromosome inactivation [7, 27-32]. The majority of BRCA1-associated cancers are also triple-negative (ER, PR and HER2 negative), express basal cytokeratins and other markers commonly seen in basal-like breast cancers (e.g. p53, P-cadherin and EGFR) [7]. Gene expression profiling also demonstrated that BRCA1-associated cancers segregate strongly with basal-like breast cancers [2, 29, 33, 34]. Although BRCA1 somatic gene mutations are uncommon in sporadic basal-like cancers, these tumors have been shown to have a dysfunction al BRCA1 pathway due to BRCA1 gene promoter methylation and/or BRCA1 pathway transcriptional inactivation [7, 25, 26]. The fundamental biological similarities between hereditary BRCA1-related breast cancers and basal-like cancers suggest that strategies targeting the dysfunctional BRCA1 pathway may be effective in basal-like breast cancers. There is increasing evidence that the DNA repair defects characteristic of BRCA1 related cancers, especially defective homologous recombination, confer sensitivity to certain systemic agents, such as platinum-based chemotherapy and poly(ADP-ribose) polymerase (PARP) inhibitors [34-38]. Indeed, recent clinical studies revealed that sporadic basal-like cancers responded to platinum-based chemotherapy and were associated with a high rate of complete pathologic response [9, 11, 38]. Consistent with the clinical data, our in vitro study also reveals that basal-like breast cancer cells confer specific sensitivity to cisplatin as compared to other chemotherapeutic agents (e.g. doxorubicin or paclitaxel) (Figure 1), further support research into the utility of platinum-ba sed agents in basal-like breast cancers. Given the high specificity and response rate of basal-like breast cancers toward platinum-based therapy, our focus is to maximize the benefits associated with this therapy through drug combination strategies. Using a small chemical library consisted of 160 well-validated and specific inhibitors that target the human kinome, we have identified 6 compounds that significantly potentiate the antiproliferative effects of cisplatin in basal-like breast cancer cells. These compounds include rapamycin, LY364947, AG1478, BAY11-7082, LY294002 and SB203580 which targets the mTOR, TGFà ¯Ã‚ Ã‚ ¢RI, NFà ¯Ã‚ Ã‚ «B, PI3K/AKT and MAPK pathway respectively. Of note, these pathways have been reported previously to be over activated in basal-like breast cancers [7, 17, 18, 20]. To further investigate the mode of interaction between these compounds and cisplatin, we performed a drug combination study using the isobologram approach as described previously (Ref). Out of the 6 compounds identified, rapamycin showed the strongest synergistic effects with cisplatin while others (LY364947, AG 1478, BAY11-7082, LY294002 and SB203580) showed mainly additive effects. This result is consistent with other studies which show that inhibition of mTOR by RNAi or small molecules (e.g. rapamycin, CCI-779, RAD001) enhances cisplatin chemosensitivity in ovarian [39-41], endometrial [42], head and neck [43, 44], lung [45], skin [46, 47] and liver [48] cancers. We next compared the synergistic effects of rapamycin in combination with cisplatin in a panel of luminal-like and basal-like breast cancer cell lines that has been previously validated by gene profiling [15]. Intriguingly, the synergistic effects were observed only in MDA-MB-468, MDA-MB-231 and HCC1937 basal-like cells, but not in MCF-7 or T47D luminal-like cells. Several models have been proposed to explain the synergistic effects of rapamycin and cisplatin in cancer cells. Beuvnk et al., 2005 showed that RAD001 (Everolimus), a rapamycin derivative, dramatically enhances cisplatin-induced apoptosis in wild-type p53 but not mutant p53 tumor cells by inhibiting p53-induced p21 expression [49]. Wangpaichitr et al., 2008 demonstrated that inhibition of mTOR by CCI-779 decreased levels of the anti-apoptotic proteins, BCL2/BCLxL, and increasing apoptosis in lung cancer cells that is resistance to cisplatin [50]. Although these models provide important evidence for mTOR inhibition and cisplatin synergism in cancer cells, it fails to explain the specific synergism we observed in basal-like breast cancer cells, as the basal-like cells that we tested are p53 mutated and do not express high level of BCL2/BCLxL (data not shown). This led us to postulate that a common signal transduction pathway inhibited by rapamycin may be an important component that sy nergizes cisplatin sensitivity in basal-like cells. Since p73 has been reported to mediate cisplatin sensitivity in a subset of triple-negative breast cancer cells [4] and that inhibition of mTOR by rapamycin or RNAi lead to upregulation of p73 [21], we postulated that activation of the p73 pathways might be important for the synergistic effects of rapamycin. To test the role of p73 in rapamycin and cisplatin synergism, we first evaluated the expression of p73 mRNA and protein levels following treatment with cisplatin or rapamycin alone or in combination in MDA-MB-231 cells. Consistent with previous studies, treatment of cells with cisplatin or rapamycin alone induces p73 protein expression followed by transcriptional activation of the 2 potent pro-apoptotic p73 target genes, PUMA and NOXA. When MDA-MB-231 cells were co-treated with rapamycin and cisplatin, the elevation of p73 and its pro-apoptotic target genes were synergistically enhanced. The observed changes in p73 protein in MDA-MB-231 cells, however, were not due to parallel changes in p73 RNA levels, suggesting that inhibition of mTOR might lead to inactivation of a yet unknown p73 specific protein degradation pathway. To validate that the rapamycin and cisplatin synergism is mediated by p73, we generated isogenic MDA-MB-231 and MDA-MB-468 cells that were depleted for p73 using a lentiviral-shRNA that target specifically the transactivating isoform of p73 (TAp73). Indeed, depletion of TAp73 in MDA-MB-231 and MDA-MB-468 cells completely abrogated the synergistic effects of rapamycin suggesting that the synergism between rapamycin and cisplatin required p73 function. Although the combination of cisplatin and rapamycin has not been previously investigated in clinical study, it is worth noting that a phase II neo-adjuvant clinical trial of cisplatin and RAD001 (Everolimus), in patients with triple-negative breast cancers has recently open for recruitment (ClinicalTrials.gov Identifier: NCT00930930), and will be able to address the potential of cisplatin and mTOR inhibitors combination therapy directly. It would be equally intriguing to determine the role of p73 related pathway as potential biomarkers that might predict response to treatment given the pivotal role of p73 in the synergistic effects of mTOR inhibition and cisplatin sensitivity. In conclusion, combination of mTOR inhibitors and cisplatin may be a useful therapeutic strategy in basal-like breast cancers.

The congenital heart disease

The congenital heart disease Does an Exercise Program following Cardiac Surgery for Congenital Heart Defects improve a Childs Cardiopulmonary Response to Exercise and Increase Exercise Tolerance? Introduction   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Paediatric Cardiac Problems are prevalent throughout the world with 1.5 million new cases diagnosed each year. Congenital Heart Disease (CHD) is the most common diagnosis of heart problems at birth. Between four and nine per one thousand live births each year are diagnosed with the condition (Draper 2008). In 2007, 989 live births were recorded of babies with cardiovascular abnormalities (National Statistics 2007). Congenital Heart Disease is an umbrella term which encompasses all heart defects that are present when a child is born. The child may have one or multiple defects at birth which can either be detected by a scan ante-natally or are diagnosed soon after birth. Although the diagnosis of CHD is now becoming easier, some diagnoses of the condition do not happen till later on in life. Statistics show that around 60% of congenital heart disease are diagnosed in babies aged from birth to one year, 30% in children aged one to fifteen, and 10% in adul thood (16 years and over) (BHF 2003). Many common conditions include a Ventricular Septal Defect (VSD), an Atrial Septal Defect (ASD), Pulmonary Artery Stenosis, Tetralogy of Fallot (TOF) (Fig. 1) and Transposition of the Great Arteries (TGA) (Fig. 2). Congenital Heart Disease is now not just a problem of the child, many people with the condition are now living into adulthood. It is predicted that by 2010, 185,000 people will be living in the UK with CHD (Deanfield (BHF) 2003). Treatment for Congenital Heart Conditions has changed rapidly over the last 50 years. Now surgical management is needed in most cases however some defects will either resolve themselves or require medication. Surgical treatment has changed in recent times, fewer patients are requiring open heart surgery and more are receiving a catheterisation technique. Around 3,100 operations and 725 interventional cardiac catheterisations are performed each year on babies and children with CHD (BHF 2003). The effects of surgical interventions on cardiopulmonary function have been thoroughly researched in the past. The studies have concluded that surgery does improve lung and cardiac function and reduces secondary complications (Picchio 2006). Exercise is widely known as the best treatment for most musculoskeletal problems but its effects on the cardiopulmonary system has only recently been researched into (Cullen 1991). Pulmonary and Cardiac Rehabilitation have now been shown to have an effect in adults but the research into paediatric rehabilitation classes is not widely known about. Other studies have looked at exercise training or a cardiac rehabilitation programmes following surgery and the effect of this on the patients exercise tolerance. I am going to use this review to assess these studies which look at both cardiac rehabilitation programmes and also levels of exercise tolerance following surgery. I want to discuss whether there are any gaps in the knowledge base surrounding the effects of exercise in cardiac surgery of paediatrics. I also want to conclude whether the assumption that exercise is positive, can be correctly justified. Method After deciding a topic I was able to start researching into the background area of paediatric cardiology. I started by using a combination of terms including, Exercise, Sports, Physical Activity, Paediatrics, Children, Post-Cardiac Surgery, Congenital Heart Disease, Congenital Heart Defects and Cardiac Rehabilitation. The search pages I found highlighted articles of relevance and then I used the link to related articles to find the studies (see appendix 1). I also searched on individual journal websites including, Paediatric Cardiology and Cardiology in the Young. I used databases such as Pubmed, Medline, Ovid, Sciencedirect and Springerlink to read abstracts of articles and decide their relevance to my review. I then selected the most relevant and used excel to compile a table where I could easily see the differences in the studies under headings (see appendix 4). The studies I am looking at are all based on paediatrics and are randomised controlled trials dating from 1981 to 2009. Although some of the studies are nearly thirty years old, they hold some strong evidence compared to present day studies and therefore I have not discounted older studies from this review. Other reviews have assessed whether exercise has an impact on cardiopulmonary performance and have been shown that an exercise rehabilitation class does provide benefits in cardiopulmonary performance and exercise capacity. Some of the studies that are being reviewed however are concluding with insignificant findings. The reviews have stated that research lacks long-term effects of training and also a clear understanding as to which exercise type is best (Tomassoni 1996). In this review I will try look at newer studies and see if the areas of knowledge that were found to be omitted after previous reviews have now been researched into. Review of Studies Firstly I am going to discuss the testing of the participants. All of the studies completed two exercise tests to assess the participants ability before and after either the cardiac rehabilitation program or surgery. Exercise testing is very difficult to reproduce. Many studies have problems with ensuring the test is accurate and reliable and many struggle, causing results and testing to be different and therefore not comparable. If the results are not accurate and cannot be compared to other studies the results can cause a change in average results and therefore may mislead readers into a false positive result. Each of the studies used either a treadmill test or a cycle ergometer to test their participants cardiopulmonary function and exercise tolerance. Using these two tests is the most common technique of testing function as it is very reliable. (Washington 1994) All studies used a specific protocol outlined in the Washington Guidelines with all of the studies using a treadmill test with five of the thirteen studies using Bruces protocol. Bruces protocol is where the grade of exercise is increased every 3 minutes until the participant has reached their maximum capacity and cannot continue. The bicycle ergometer tests are where the participants are required to cycle continuously at approximately 50-60rpm where the grade of exercise is increased by 10-20 watts/ minute every three minutes. This is also completed until the participant can no longer continue (Washington 1994). Exercise testing using a treadmill or a cycle ergometer causes problems because the task they are undertaking in the test are is not functional and do not relate to daily tasks. Running and cycling is functional but not to that grade of exhaustion. Many children normally will stop an exercise when they are tiring and will never push themselves to the level that these exercise tests are pushing them. The tasks are also not fun for the participants and I feel that it should be fun otherwise children will get bored. This is the same with the intervention as well and the programmes should be child orientated and individual to each child. Outcome Measures are the basis to the results of a study and therefore its effectiveness. A lack of certain outcome measures may show large flaws in a study as many can be used to assess different parts of function and physiological activities. In the studies looking at the effects of cardiovascular surgery, there were a limited number of outcome measures that were looked at. Sarubbi (2000) only looked at heart rate and blood pressure as outcome measures and this limits results. The main outcome measures were heart rate, blood pressure and maximum work rate in all the studies. These outcome measures although very limited are values that help us to understand cardiovascular activities. Other helpful measures would have been oxygen saturations, which only Rhodes studies (2005/6) looked into. Saturations are helpful to assess whether a change in heart rate or blood pressure affects saturations or whether a change in these may be due to a ventilation problem. (Rivers 2001) The outcome measures of the cardiac rehabilitation studies are all different but all have similarly looked at exercise capacity after the intervention. This is shown by all the studies using VO2 as a measure and that all the participants improved their VO2 maximum to allow for a greater exercise capacity. The only study that did not prove an increase in VO2 max was Goldbergs study (1981) which only showed an improvement in maximum work rate. This could have been due to the date in which the study was undertaken. This was one of the earlier studies done in 1981 and therefore technology may not have been as accurate or as reliable as some of the later studies done since 2000. However Goldbergs study was the one that had the most intervention time of all the studies with exercise of up to 45 minutes completed on alternate days with a strict regime to increase grade of exercise over the 6 weeks. This leads me to believe that maybe it was inappropriate testing or inaccurate technology tha t changed the results of the study as previous reviews have shown that an increase in exercise time has shown to have positive effects on health. As technology has developed since the early eighties, this may be why more accurate testing is used and therefore making results more positive to the outcome we wish. Another problem in trials of this sort is compliance. Compliance is always an issue when completing studies (Burke 1997). Initially recruiting people to participate is difficult and many people with either choose not to participate or may drop-out early in the study. Many people will not participate because of exercise testing being too invasive or because of geographical implications as the distance to the base of the study being an issue. Some of the studies had large drop-out rates with almost 30% decrease in patients initially viable for the treatment plan and those who undertook the tests in the study (Arvidsson 2009). I think this could be explained by that the studies involved child participants that are less compliant to long term programmes and who tire easily to an activity. Also due to the nature of the surgery that they have all completed, many parents will be protective over their children and be pushing the participants exercise tolerance will make many parents worried about their childs health. Much of this can be avoided by specifically explaining the procedures and answering any questions that the parent or participant may have to educate them that this a treatment plan and is not going to hinder their childs recovery or health. Also intervention time is a major issue when looking at trials. Some may be days long and others have follow-ups of years once the intervention has finished. The studies that focus on Cardiac rehabilitation all have various time scales of their intervention with the shortest program being six weeks (Goldberg 1981) and the longest around twenty weeks (Opocher 2005). The difference in timescale and the different number of sessions that the participants attend makes it difficult to assess whether it is the content of the program that affects the patients or whether just exercising over a longer, more sustained period of time effects the participants in the same way. I think studies that look at different contents of treatment programmes but have a fixed intervention time may be beneficial in deciding the aim of this review. When looking at the studies, all of the cardiac rehabilitation programs only assess the patients exercise performance straight after the program and only one study looks at the effects of the program long term. Rhodes et al 2005 firstly looked at the immediate effect of a cardiac rehabilitation program and then in 2006 did another study looking at the same participants of the previous study six months after the original program. The studies that look at exercise capacity before and after surgery also do not look at the effects of the cardiovascular system in response to exercise on a long term scale. Long term effects are the best indicator to say that function and exercise capacity has improved (Miller 2005). Sociodemographics of the subjects in a study are also important to review as to its involvement in accuracy of results. Different age ranges or male to female ratios cause studies to be inaccurate in trying to generalise the population group. Many of the studies had a very large age range within their participant groups with the largest difference being 17.6 years in Marino et als study in 2005. I feel that the exercise difference between a seven year old is very different to that of a twenty-four year old. I feel that a large age range is used to increase subject numbers. Male: Female ratios are also important and that a large majority in these studies had male participants. The biggest ratio of male to female was in Opochers (2005) study where there were nine male participants and only one female participants. The best ratio of male: female was either Moalla (2006) study with 44 males and 39 females. This is important as I believe men and women react differently to exercise. Subject numbers is also a large problem with these studies. Due to most of the studies only looking at the children that have had surgery in their trust or hospital they have decreased their subject numbers and none of the studies look at the effects on large number of subjects on a national scale. The studies that looked at cardiac rehabilitation all have subject numbers under 16 which is a very big limitation. The only studies that have larger numbers are the ones that look at exercise capacity after surgery. By having participants that are only from the immediate area of the study base also means you do not get a generalised view of everyone nationally and you may not cover different children from different backgrounds socially and economically and so may have different attitudes to rehabilitation, treatment and self-management. Studies with participants that are not generalised to their population group can therefore produce a bias result to that specific population group. Also having different backgrounds of participants is important in assessing their compliance and what individual exercise programme they should be given. Having a specific age range is particularly important as many of the subjects may be inappropriate for the programme due to their age. Some of the subjects may be too young and using subjects that are under six years old would be inappropriate due to the subjects being too young to understand the instructions of the study. Using older subjects may also cause different results as their bodies have had longer to regain independent function and the body has had time to compensate for a lack in cardiopulmonary function. I think it is important to keep variables as succinct as possible and trials should be able to based on one variable alone and truly work on whether surgery or exercise has a n effect on that variable independently. Effects of Cardiac Rehabilitation The studies looking at cardiac rehabilitation all have an exercise programme set up for their patients either at home (Moalla 2006) or in an outpatient setting (Ruttenberg 1983). These sessions ranging in therapy time from one hour alternate days to one hour once a week, all show an increase in either cardiopulmonary performance or in exercise tolerance. This shows that a rehabilitation programme is appropriate for these patients and does have a positive effect on the participants life. Rhodes studies (2005/6) had the greatest effect on the patients final outcome. Not only did most of the testing result in significant effects but the large range of outcome measures used means that we can assess not only the cardiovascular performance of the participant but also look at the pulmonary effects of the exercise and their effects of the heart and the cardiac system. What we can also see from this review is that the cardiac rehabilitation programmes are becoming more significant in results as the studies get newer. This is a good indicator that current programmes are being effective in their rehabilitation (Opocher 2005, Rhodes 2005/6, Moalla 2006) and that newer techniques and more knowledge on exercise has lead to better run classes which not only improve results more consistently than the older studies and that the effects from an initial programme can also be maintained for 6months after intervention (Rhodes 2006). Effects of Cardiovascular Surgery Two of the studies looking at effects of surgery only have exercise testing after the surgery. The study by Arvidsson only used the number of sports sessions a week that the participant goes to after the surgery. Therefore a direct comparison between their before and after the surgery ability cannot be done and so the study is only looking at their sports participation after surgery and not the effects of the surgery. However these studies do show that after surgery childrens exercise tolerance increases to the level that healthy participants are achieving (Zaccara 2003) and they are participating in equal amounts of sports participation following surgery (Arvidsson 2009) Future ideas In future studies, long term effects of cardiac rehabilitation should be researched, with a follow-up test of a least a year after their rehabilitation to see if the participant is now more active. I also think a control group should be used in the study to look at the effects of non-surgical patients that also participate in cardiac rehabilitation. This is to assess whether the improvement seen during cardiac rehabilitation is not just a response to any exercise and that if a child went back to normality and participating in sports then they will just be as exercise tolerant as children who do not have CHD. Also I would suggest that an exercise programme for the patients that is more functional but also fun and exciting for the patient should be used to increase compliance and also enjoyment for the participants and their parents. Conclusion In conclusion, Cardiac surgery is a commonly used form of reducing congenital heart defects and has been shown by these studies that the surgery does have an improvement on the patients cardiopulmonary performance. I have also found that a cardiac rehabilitation programme is beneficial for paediatric patients after cardiac surgery for congenital heart defects. References/ Bibliography Arvidsson, D (2009) Physical Activity, sports participation and aerobic fitness in children who have undergone surgery for congenital heart defects. Acta Paediatrica 98 pp. 1475-1482 Balfour, I. (1991) Pediatric Cardiac Rehabilitation. AJDC- Volume 145 pp. 627-630 Bradley, L. (1985) Effect of Intense Aerobic Training on Exercise Performance in Children After Surgical Repair of Tetralogy of Fallot or Complete Transposition of the Great Arteries. The American Journal of Cardiology Volume 56 pp.816-818 Burke, L. (1997) Compliance with cardiovascular disease prevention strategies: A review of the research. Annals of Behavioural Medicine. Volume 19, number 3, pp. 239-263 Cullen, S. (1991) Exercise in Congenital Heart Disease. Cardiology in the Young; 1: pp. 129-135 Deanfield J. (2003) Congenital Heart Disease Statistics (accessed on 8/11/09) British Heart Foundation Statistics Database www.heartstats.org disease participate in sport and in which kind of sport? Journal Of Cardiovascular Medicine, 7: pp. 234-238 Draper, Dr. Richard (2008) Congenital Heart Disease in Children (accessed on 3/11/09) http://www.patient.co.uk/doctor/Congenital-Heart-Disease-(CHD)-in-Children.htm ECHO (Evelina Childrens Heart Organisation) (accessed on 15/11/2009) http://www.echo-evelina.org.uk/ Goldberg, B. (1981) Effects of Physical Training on Exercise Performance of Children Following Surgical Repair of Congenital Heart Disease. Pediatrics Vol. 68 No.5 pp. 691-699 http://graphics8.nytimes.com/images/2007/08/01/health/adam/18088.jpg http://graphics8.nytimes.com/images/2007/08/01/health/adam/8807.jpg Marino, B. (2006) Exercise Performance in children and adolescents after the Ross procedure. Cardiology in the Young 16: 40-47 Miller, T. (2005) Exercise rehabilitation of paediatric patients with cardiovascular disease. Progress in Paediatric Cardiology Volume 20, pp. 27-37 Minamisawa, S. (2001) Effect of Aerobic Training on Exercise Performance in Patients After the Fontan Operation. The American Journal of Cardiology Volume 88 pp. 695-699 Moalla, W. (2006) Effect of exercise training on respiratory muscle oxygenation in children with congenital heart disease. European Journal of Cardiovascular Prevention and Rehabilitation 13: 604-611 National Statistics (2007) Congenital anomaly Statistics Notifications. Office for National Statistics. Series MB3, no.22 Opocher, F. (2005) Effects of Aerobic Exercise Training in Children After the Fontan Operation. The American Journal of Cardiology Vol. 95 pp.150-152 Picchio F. (2006) Can a child who has been operated on for congenital heart Rhodes J. (2006) Sustained Effects of Cardiac Rehabilitation in Children with serious Congenital Heart Disease. Paediatrics Volume 118:3 pp.586-592 Rhodes, J. (2005) Impact of Cardiac Rehabiliation on the Exercise Function of Children with Serious Congenital Heart Disease. Pediatrics Volume 116:6 pp.1339-1345 Rivers, E. (2001) Central venous oxygen saturation monitoring in the critically ill patient. Current Opinion in Critical Care. Volume 7, issue 3, pp. 204-211 Ruttenberg, H. (1983) Effects of Exercise Training on Aerobic Fitness in Children after Open Heart Surgery. Pediatric Cardiology Vol. 4, No. 1, pp. 19-24 Sarubbi, B. (2000) Exercise Capacity in Young Patients after Total Repair of Tetralogy of Fallot. Paediatric Cardiology 21: 211-215 Tomassoni, T. (1996) Role of exercise in the management of cardiovascular disease in children and youth. Medicine Science in Sports Exercise. Volume 28(4), pp 406-413 Washington RL. Et al. (1994) Guidelines for exercise testing in the pediatric age group. Journal of the American Heart Association. Volume 90;pp. 2166-2179 Zaccara, A. (2003) Cardiopulmonary Performances in Young Children and Adolescents Born with Large Abdominal Wall Defects. Journal of Pediatric Surgery Volume 38;3 pp 478-481

Blindness In Oedipus The King Essay -- essays research papers

Blindness plays a two-fold part in Sophocles’ tragedy “Oedipus the King.'; First, Sophocles presents blindness as a physical disability affecting the auger Teiresias, and later Oedipus; but later, blindness comes to mean an inability to see the evil in one’s actions and the consequences that ensue. The irony in this lies in the fact that Oedipus, while gifted with sight, is blind to himself, in contrast to Teiresias, blind physically, but able to see the evil to which Oedipus has fallen prey to. Tragically, as Oedipus gains the internal gift of sight, he discards his outward gift of sight. Sight, therefore, seems to be like good and evil, a person may only choose one.   Ã‚  Ã‚  Ã‚  Ã‚  Teiresias, prophet of Phoebus, was stricken with blindness to the physical world, but, as a result, gained the gift of sight into the spiritual world. This great gift allowed him to become a superior prophet, praised by the people as “god like'; and as a person “in whom the truth lives.'; Therefore, it was no surprise that Oedipus asked the old prophet to come before the people to enlighten them as to who or what the cause of the plague decimating their country was. What Oedipus was not expecting, however, was that the sin he could not see himself was to blame for the judgement being poured out upon the country. The sin so hidden from Oedipus’ and the peoples’ eyes was quite visible to Teiresias. What Teiresias ... Blindness In Oedipus The King Essay -- essays research papers Blindness plays a two-fold part in Sophocles’ tragedy “Oedipus the King.'; First, Sophocles presents blindness as a physical disability affecting the auger Teiresias, and later Oedipus; but later, blindness comes to mean an inability to see the evil in one’s actions and the consequences that ensue. The irony in this lies in the fact that Oedipus, while gifted with sight, is blind to himself, in contrast to Teiresias, blind physically, but able to see the evil to which Oedipus has fallen prey to. Tragically, as Oedipus gains the internal gift of sight, he discards his outward gift of sight. Sight, therefore, seems to be like good and evil, a person may only choose one.   Ã‚  Ã‚  Ã‚  Ã‚  Teiresias, prophet of Phoebus, was stricken with blindness to the physical world, but, as a result, gained the gift of sight into the spiritual world. This great gift allowed him to become a superior prophet, praised by the people as “god like'; and as a person “in whom the truth lives.'; Therefore, it was no surprise that Oedipus asked the old prophet to come before the people to enlighten them as to who or what the cause of the plague decimating their country was. What Oedipus was not expecting, however, was that the sin he could not see himself was to blame for the judgement being poured out upon the country. The sin so hidden from Oedipus’ and the peoples’ eyes was quite visible to Teiresias. What Teiresias ...

Essay --

Euthanasia is a well- discussed topic that includes multiple perspectives on the ethics of it. This is an important issue for any society to reconcile because it is a life and death issue. Euthanasia is a highly personal decision that can be made for many reasons. The moral and ethical concerns over euthanasia don't take into account the dignity of the one dying. Who decides the quality of a human's life? We did not have the chance to choose if we wanted to come here, so should we be entitled to the honor of choosing to leave? Over the years, the laws and ethical concerns regarding the controversial topic of euthanasia have been questioned repeatedly by society. Many have found it difficult to see their way through the many existing resources without feeling some hopelessness that the conflicting ideas on mercy-killing might one day be resolved. Euthanasia is defined as the painless killing of a patient suffering from an incurable and painful disease or in an irreversible coma. It is also called â€Å"Physician- Assisted Suicide† or, â€Å"PAS† for short. The term comes from the Greek expression for "good death." Now, this short definition is a cause of debates all over the world. Doctors, politicians, religious leaders, lawyers, and general public argue over the law that would allow or forbid euthanasia. There are only two countries, which allow Physician Assisted Suicide; these are Netherlands and Belgium, and the state of Oregon in the United States. The issue of euthanasia has been an important turn in history for its differing points of view on the ethics. The first usage of the term "euthanasia" was from the historian Suetonius who described how the Emperor Augustus was, "dying quickly and without suffering in the arms of his wife, L... ...eligion does not think that a human being has a right to decide whether to die or not. As previously stated, as it was already mentioned is too subjective, and in general cannot be compared with the human’s sufferings, human’s unbearable pain and freedom to choose whether to continue living or not, and euthanasia should be better legalized in order to gain control over that process. I therefore conclude that no one can claim to truly know whether, or in what circumstances, euthanasia is moral or not. With the differing perspectives and opinions about Physician Assisted Suicide it is possible to try to answer this question by discussing the moral issues, but also it is not easy to say whether euthanasia is ever morally supportable. Of course, euthanasia should be differentiated from simple removal of life support from a patient who has already effectively succumbed.

Galactic Center at Very High Energies Essay -- The Universe, Black Hol

Every time a new ‘‘messenger† (different photon wavelengths or a different particle) has added to the list of observables accessible to astrophysicists, the Universe has appeared under a new light: it has revealed surprising features and triggered new questions, ultimately changing our understanding of fundamental physics and cosmology.Examples include the new elementary particles discovered in cosmic rays in the ‘30s and ‘40s, flavor oscillations from the solar and atmospheric neutrinos, or the revolutions brought by radio or X-ray astronomy. The last decade, a new branch of astronomy was born: high energy and very high energy gamma-ray astronomy. Especially, 2OO4 was a very importand year for the gamma-rays astronomy. Firstly it was the year that marked the 30th aniversary of the discovery of the compact radio source Sgr A* (Balick and Brown 1974) which is now strongly believed to be the revelation of a supermassive black hole of a mass of (3 imes 10^{6} M odot ) that seats in the rotanional center of the Galaxy, according to the measurments of star motions near the Galactic Center (GC). Moreover it was the year that the first detection of gamma-rays from a compact region of size (sim 10') around Sgr A* with the INTEGRAL ( extit{International Gamma-Ray Astrophysics Laboratory } ) observatory in the energy rage from 20 to 100 keV (Belanger et al 2004) and with the HESS (High Energy Stereoscopic System) Cerenkov telescope array between 165 and 10 TeV (Aharonian et al 2004) took place. The detection of a high energy radiation source that appears to be pointlike and coincident with the Galactic Nucleus seems to be the reword of 30 years of observations. The GC is now observed also by the Fermi space observatory. When J.Co... ...i.e. within (sim 100 ) Schwarzchild radii of the black hole). This fact must be explained by any model for the TeV gamma-rays and it seems to support the scenario where the gamma-rays are assosiated with electrons accelarated by the pulsar wind nebula. However, protons may be accelarated close to the black hole, but be converted to gamma-rays only after travelling a significant distance away from the accelaration region (e.g. Atoyan n Dermer 2004; Aharonian n Neronov 2005; Ballantyne et al. 2007a). In the scenario presented by Ballantyne et al. (2007a), proton accelaration was assumed to occur at distances only (sim 20-30 ) Scwarzchild radii from the black hole (e.g. Liu et al. 2006). The particles would then diffuse away from the Sgr A* through the magnetized turbulent ISM ? , until possibly colliding with the dense molecular gas in the circumnuclear disk.

Elderly or Old Age Stage of Development

Participant’s Cultural BackgroundThe elderly woman is a Caucasian living in the United States and has been living within the culture of the west throughout her life. Therefore, her life has not been adversely affected by other cultures. The Western culture is such that it emphasizes individualism and independence thus each person seeks autonomy through education, employment and involvement in various social activities. Information provided to me indicated that she was a teacher before she retired and involved herself in community work. In particular, her social work revolved around providing guidance and counseling services to young adults and adolescents.According to Schulz & Jutta (1996, p. 704), aging is not universal and affects people in different ways as influenced by diverse factors that the individual is exposed to, among them being education, social support, diet and nutrition. These factors mediate the process of aging thus determine the success or failure of aging. Generally, the participant had been influenced by the factors especially education, nutrition and social support. The participant had been influenced by education owing to the fact that before her retirement, she had been a teacher and lived with her family who provided her with social support and adequate nutrition.She is a Caucasian thus culturally, her family is keen on her diet and wellbeing. Setting where participant was observed I observed the participant in her home where she lives with her family for a week. I was able to make my observations constantly because the participant does not live far from where I reside. The house is medium in size and houses six people with the participant being the oldest. She lives with her son, the son’s wife and their two children as well as a nanny. There is an open back yard behind the house where there is a swimming pool and a garden with flowers and grass.The elderly woman spends most of her day in this area with the assistance of a nurse and in some occasions in the company of her son and grandchildren. She generally deals with various aging issues. For instance, she is dealing with retirement and decreased income, dealing with loss of spouse and getting ready for her own period of death. She does not engage in energy demanding activities such as walking long distances, climbing the stairs, lifting heavy objects, among others. She claims that whenever she involves herself in strenuous activities, she breathes a lot.According Leahy, Grafe and Fuzy (2004, p.  124), when people grow older, their blood circulation becomes less efficient hence they become sensitive to diverse things such as energy demanding activities and extreme temperatures. In general, I made my observations within the compound in which the participant was residing in. During my one week of observation, I did not see her travel but she always saw her family off whenever they were going out. Behaviors displayed At this stage of development, t here are a number of behavioral characteristics that can be observed in the elderly participant physically, socially and psychologically.This is because the individual is likely to have retired, thus undergone significant evolution. 92 years of age means that the person is shifting towards the end of his or her life cycle. It is often a time when they can spend time with their grandchildren, engage in leisure activities and overlook the issues that caused stress and anxiety in the prior decades. The participant was participating in some activities that enabled her to enjoy her aging. For example, in the mornings, I would see her in the garden either trying to trim the flowers, water the garden or plant more flowers in the flower pots.Although the pace of engaging in the activities was slow, she seemed to enjoy doing that work and it sometimes required the intervention of the nurse to stop her from gardening. According to Peck’s theory, during old age, an individual experience s Ego Differentiation vs. Work Role Preoccupation where the elderly individual is prone to cling to lifestyles that he or she previously lived or engage in activities that enhance their self esteem (Saxon, Saxon & Etten, 2002, p. 26). The participant had slower responses as well as reflexes.When she is asked about something, I observed that she took a while before she responded. In addition, she seemed to be forgetting various instructions within a short period of time especially in situations when the instructions or information given were verbal. I realized this after she asked my name a couple of hours after I had told her. However, she had definite memory of visual gestures because she could spot her son’s car from a distance. According to Leahy, Grafe and Fuzy (2004, p. 123), aging affects the person’s ability to remember and concentrate because it affects memory.It is difficult for the old to think fast and logically due to old age. However, the degree of memory loss differs with individuals. In most cases, the elderly often experience memory loss of recent activities whereas past activities are easily remembered. The elderly woman has lost several things ranging from independence, friends, health to family although she may have increased wisdom. The elderly are faced with some developmental tasks such as bending with declined physical energy and loss of well being. This is indicated by her behaviors such as having difficulties picking up things when they fall.For example, during one of my observations, she was walking towards the car but her hat was blown off by the wind. However, she was not able to bend and pick hence was assisted by her grandson. In addition, her reaction to the hat that had been blown off was slow in both speed and verbal response. Saxon, Saxon and Etten (2002, p. 26) point out that in the process of aging, Body Transcendence vs. Body Preoccupation influences the elderly to an extent that for older adults with the capa city to rise above preoccupation with their health, they have the ability to engage in activities that grant them individual satisfaction.Her vision, taste, hearing, and smell are quite poor. For her vision, she usually has difficulties reading and noting details in some visual objects and this explains the reason why she always wears her spectacles. She is not able to see small sized objects. For example, in case a button falls on the carpet, she cannot find it. Her taste is also poor because she always complains about food and drinks. For instance, she often complains about food having inadequate salt which is rarely the case or that the fruit juice given to her is tasteless.Her hearing has been impaired by old age because when communicating with her, one has to speak loudly or talk close to her ears. On several occasions, her grandchildren are forced to almost shout so that she can hear them. This has brought frustration to the participant owing to the fact that she finds it stre nuous to communicate with those around her. In the course of my observation, I noted that the participant did not have a good sense of smell. I made this observation when the nanny burnt the food and while everyone else was finding fault in the strange smell, she just said, â€Å"I don’t smell anything†.Schulz & Jutta (1996) point out that during aging, it is common for the elderly to loose their senses of smell, touch, taste, hearing and sight. This is attributed to the decline in the ability of the senses of the body to function adequately. In conclusion, it is evident that old age results to changes in diverse aspects of life to psychological and physical changes in the life of the elderly. Aging affects persons differently depending on factors such as nutrition, social support, education and diet.Conversely, aging generally results to a decline in the ability of the body to function due to a decline in the capacity of a number of body parts to function e. g. respir atory system, urinary system, circulatory system, nervous system, and musculoskeletal system and hence affecting the activities they get involved in. Therefore, at old age, the elderly should be well taken care of because they do not have the ability to function effectively as they used to in their previous years (Leahy, Grafe & Fuzy, 2004). References Leahy, W., Grafe, J. & Fuzy, J. L. (2004). Providing Home Care: A Textbook for Home Health Aides. Albuquerque: Hartman Publishing Inc. Saxon, V. S.S, Saxon, V. S. & Etten, M. J. (2002). Physical Change & Aging: A Guide for the Helping Professionals. New York: Springer Publishing Company Schulz, R. & Jutta, H. (1996). A Life Span of Successful Aging. Journal of American Psychologist. Vol. 51 (7), pp.702- 714

Public Safety

There has widespread public outcry on issues relating to safety, women are purported to be the main victims as they were the ones that most attacked at called the attention of relevant authorities. A series of interviews were carried out on three different women to on matters relating to public safety. This was in action to decipher the extent of the threat or imminent threats they faced, how they felt about it, how they would prevent or defend themselves when in such unfortunate situations and the recommendations that they would have to the public safety department in a bid to lower the risks of being attacked. The city was rated to be the least safe place in the country, but there were a few exceptions to the status quo. From the interviews it was discovered that all the respondents rated their hoods unsafe and they would prefer staying indoors all the time if need be. They all felt secure when in malls, places near the police station and mostly banks. There was a mixed answer in the places that were presumed to be less secure; I categorically picked the word ‘presume' because none of the respondents reported that they had ever been attacked or molested in the places they mentioned. The market place was rated to be the least secure place, then the central business district followed and deserted allays closed the list of dangerous places. The respondents felt secure in markets and the CBD because the probability of one noticing danger or more so evade it was very low. None of them had been attacked but they felt most insecure when in those two areas, deserted alleys were marked as red zones because one would feel very helpless when confronted in such places. Barber shops and clubs also fell into sharp criticism as their securities were termed inefficient for such crowded areas. Other people would opt to call for private barber services than risk exposing themselves to the areas they termed crime prone. Word was that no one could risk walking outside alone but if the situation forced it then they would either call some other person to tell them how insecure they feel then walk lit pathways or walk in a group of more than 10 people to boost personal security. The respondents agreed that they would forego walking in the dark at all costs if they other alternatives. Rainy was said to be the most dangerous time then followed by snow seasons. I bet this because of the darkness that engulfs when these seasons come. All the respondents were women and they said that feel more insecure than men would be because they felt that male masculinity was an added advantage when it comes to lessening the imminent security threat or even fighting it off. This claim was fortified by one respondent that said that her husband would be the first person she would ever call when in a dire situation. From the investigation it was clear that none of the women had ever been publicly molested in crowded areas of mugged in deserted alleys but they all felt very insecure about the places. Maybe that was an indication that the situation has always been under control and that the police department was working; but not publicly. Their recommendations of a secure city and neighborhood would be one that has regular police patrols and one that has all streets and deserted pathways properly lit. Peoples fear can be attributed to the psychological triggers of darkness and the one of feeling accosted when in dark alleys (leer-2017). With said, it is high time the peoples recommendations be worked on so as to boost public confidence in matters relating public safety.ReferenceA Lear- 2017, behavior therapySafety behavior after extinction triggers a return of threat expectancy