972 resultados para Exposure Treatment
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OBJECTIVE This study evaluated the differences in enamel color change, surface hardness, elastic modulus, and surface roughness between treatments with four bleaching gels containing carbamide peroxide (two at 10% and one each at 35%, and 45%) and two bleaching gels containing hydrogen peroxide (two at 40%). METHODS Enamel specimens were bleached and color changes were measured. Color change was calculated using either ΔE or the Bleaching Index (BI). Then, surface hardness, elastic modulus, and surface roughness of the enamel specimens were evaluated. All measurements were performed at baseline and directly after the first bleaching treatment for all carbamide peroxide- and hydrogen peroxide-containing bleaching gels. In addition, final measurements were made 24 hours after each of a total of 10 bleaching treatments for carbamide peroxide bleaching gels, and 1 week after each of a total of three bleaching treatments for hydrogen peroxide bleaching gels. RESULTS After the last bleaching treatment, respective ΔE scores were 17.6 and 8.2 for the two 10% carbamide peroxide gels, 12.9 and 5.6 for the 45% and 35% carbamide peroxide gels, and 9.6 and 13.9 for the two 40% hydrogen peroxide gels. The respective BI scores were -2.0 and -2.0 for the two 10% carbamide peroxide gels, -3.5 and -1.5 for the 45% and 35% carbamide peroxide gels, and -2.0 and -3.0 for the two 40% hydrogen peroxide gels. Each bleaching gel treatment resulted in significant whitening; however, no significant difference was found among the gels after the last bleaching. Whitening occurred within the first bleaching treatments and did not increase significantly during the remaining treatments. Surface hardness significantly decreased after the last bleaching treatment, when 10% carbamide peroxide was used. Furthermore, significant changes in the elastic modulus or surface roughness occurred only after treatment with 10% carbamide peroxide. CONCLUSION All six bleaching gels effectively bleached the enamel specimens independent of their concentration of peroxide. Gels with low peroxide concentration and longer contact time negatively affected the enamel surface.
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BACKGROUND The European AIDS Clinical Society (EACS) guidelines are intended for all clinicians involved in the care of HIV-positive persons, and are available in print, online, and as a free App for download for iPhone and Android. GUIDELINE HIGHLIGHTS The 2015 version of the EACS guidelines contains major revisions in all sections; antiretroviral treatment (ART), comorbidities, coinfections and opportunistic diseases. Among the key revisions is the recommendation of ART for all HIV-positive persons, irrespectively of CD4 count, based on the Strategic Timing of AntiRetroviral Treatment (START) study results. The recommendations for the preferred and the alternative ART options have also been revised, and a new section on the use of pre-exposure prophylaxis (PrEP) has been added. A number of new antiretroviral drugs/drug combinations have been added to the updated tables on drug-drug interactions, adverse drug effects, dose adjustment for renal/liver insufficiency and for ART administration in persons with swallowing difficulties. The revisions of the coinfection section reflect the major advances in anti-hepatitis C virus (HCV) treatment with direct-acting antivirals with earlier start of treatment in individuals at increased risk of liver disease progression, and a phasing out of interferon-containing treatment regimens. The section on opportunistic diseases has been restructured according to individual pathogens/diseases and a new overview table has been added on CD4 count thresholds for different primary prophylaxes. CONCLUSIONS The diagnosis and management of HIV infection and related coinfections, opportunistic diseases and comorbidities continue to require a multidisciplinary effort for which the 2015 version of the EACS guidelines provides an easily accessable and updated overview.
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BACKGROUND Noninflammatory alopecia is a frequent problem in dogs. Estrogen-induced alopecia is well described in dogs, with estrogen producing testicular tumors and canine female hyperestrogenism. OBJECTIVES To increase awareness that extensive alopecia in dogs can be caused by exposure to estradiol gel used by owners to treat their postmenopausal symptoms. ANIMALS Skin biopsies from five dogs with extensive alopecia were examined. METHODS Owners were asked for a thorough case history, including possible exposure to an estradiol gel. Complete blood work and serum chemistry panel analysis were performed to investigate possible underlying causes. Formalin-fixed skin biopsy samples were obtained from lesional skin and histopathology was performed. RESULTS All owners confirmed the use of a transdermal estradiol gel and close contact with the affected dogs before development of alopecia. Histopathologic examination showed a similar picture in all five dogs. Most hair follicles were predominantly either in kenogen or telogen and hair follicle infundibula showed mild to moderate dilation. Hair regrowth was present in all five dogs after the exposure to the estradiol gel was stopped or minimized. Blood work and serum chemistry panel were within normal limits in all cases. One dog had elevated estradiol concentrations, whereas in another dog estradiol concentrations were within normal limits. CONCLUSION AND CLINICAL IMPORTANCE Alopecia can occur after contact with a transdermal gel used as treatment for postmenopausal symptoms in women. Estradiol gel used by female owners therefore represents a possible cause for noninflammatory alopecia in dogs. Estradiol concentrations are not necessarily elevated in affected dogs.
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Pneumonia is a leading cause of hospitalization in patients with chronic obstructive pulmonary disease (COPD). Although most COPD patients are smokers, the effects of cigarette smoke exposure on clearance of lung bacterial pathogens and on immune and inflammatory responses are incompletely defined. Here, clearance of Streptococcus pneumoniae and Pseudomonas aeruginosa and associated immune responses were examined in mice exposed to cigarette smoke or following smoking cessation. Mice exposed to cigarette smoke for 6 weeks or 4 months demonstrated decreased lung bacterial burden compared to air-exposed mice when infected 16-24 hours post-exposure. When infection was performed after smoke cessation, bacterial clearance kinetics of mice previously exposed to smoke reversed to comparable levels as those of control mice suggesting that the observed defects were not dependent on adaptive immunological memory to bacterial determinants found in smoke. Comparing cytokine levels and myeloid cell production prior to infection in mice exposed to cigarette smoke relative to mice never exposed or following smoke cessation revealed that reduced bacterial burden was most strongly associated with higher levels of IL-1β and GM-CSF in the lungs and with increased neutrophil reserve and monocyte turnover in the bone marrow. Using serpinb1a-deficient mice with reduced neutrophil numbers and treatment with G-CSF showed that increased neutrophil numbers contribute only in part to the effect of smoke on infection. Our findings indicate that cigarette smoke induces a temporary and reversible increase in clearance of lung pathogens, which correlates with local inflammation and increased myeloid cell output from the bone marrow.
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INTRODUCTION Extended-spectrum beta-lactamases (ESBL) and AmpC beta-lactamases (AmpC) are of concern for veterinary and public health because of their ability to cause treatment failure due to antimicrobial resistance in Enterobacteriaceae. The main objective was to assess the relative contribution (RC) of different types of meat to the exposure of consumers to ESBL/AmpC and their potential importance for human infections in Denmark. MATERIAL AND METHODS The prevalence of each genotype of ESBL/AmpC-producing E. coli in imported and nationally produced broiler meat, pork and beef was weighted by the meat consumption patterns. Data originated from the Danish surveillance program for antibiotic use and antibiotic resistance (DANMAP) from 2009 to 2011. DANMAP also provided data about human ESBL/AmpC cases in 2011, which were used to assess a possible genotype overlap. Uncertainty about the occurrence of ESBL/AmpC-producing E. coli in meat was assessed by inspecting beta distributions given the available data of the genotypes in each type of meat. RESULTS AND DISCUSSION Broiler meat represented the largest part (83.8%) of the estimated ESBL/AmpC-contaminated pool of meat compared to pork (12.5%) and beef (3.7%). CMY-2 was the genotype with the highest RC to human exposure (58.3%). However, this genotype is rarely found in human infections in Denmark. CONCLUSION The overlap between ESBL/AmpC genotypes in meat and human E. coli infections was limited. This suggests that meat might constitute a less important source of ESBL/AmpC exposure to humans in Denmark than previously thought - maybe because the use of cephalosporins is restricted in cattle and banned in poultry and pigs. Nonetheless, more detailed surveillance data are required to determine the contribution of meat compared to other sources, such as travelling, pets, water resources, community and hospitals in the pursuit of a full source attribution model.
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Prostatic carcinoma is the most prevalent cancer detected in men. Bortezomib is the first proteasome inhibitor to undergo clinical trials for several forms of cancer. Although we know this class of agent preferentially kills cancer cells, our knowledge of proteasome inhibition mechanisms of induced death is far from complete. We investigated the effects of bortezomib on the LNCaP-Pro5 (Pro5) and PC-3-Pro4 (Pro4) human prostatic adenocarcinoma cells lines. We showed a reduction in proliferation and an increase in DNA fragmentation, caspase 3 activity, and cell surface phosphatidyl serine exposure. The bortezomib-treated tumors from both cell lines were dramatically reduced, and apoptosis was induced. There was also a reduction in proliferation in the treated tumors from both cells lines. We looked at changes in the levels of the proangiogenic factors VEGF, IL-8 and bFGF in vitro and in vivo. Although there was a reduction in the levels of VEGF produced by the Pro5 cell line and tumor due to bortezomib, no similar observations were made for the other angiogenic factors or in the Pro4 cells. We investigated the effects of bortezomib on p53 in the Pro5 cell line. Bortezomib induced strong stabilization of p53. It did not promote phosphorylation on serines 15 and 24 and p53 remained bound to its inhibitor, mdm2. Nonetheless, confocal microscopy revealed that bortezomib stimulated p53 translocation to the nucleus and enhanced p53 DNA binding, accumulation of p53-dependant transcripts, and activation of a p53-responsive reporter gene. Furthermore, stable transfectants of LNCaP-Pro5 expressing the p53 inhibitor, HPV-E6, displayed reduced bortezomib-induced p53 activation and cell death. Our data shows bortezomib to induce antitumor effects in the human Pro4 and Pro5 prostatic adenocarcinoma cell lines by the direct induction of apoptosis. The drug also causes a reduction in cell proliferation and mean vessel density while modulating the secretion of proangiogenic factors. Although we show that proteasome inhibition stimulates p53 activation via a novel mechanism in Pro5 cells, it is also toxic to p53 null cells as is seen in the Pro4 line. ^
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Beryllium is a widely distributed, highly toxic metal. When beryllium particulates enter the body, the body's defense mechanisms are engaged. When the body's defenses cannot easily remove the particulates, then a damage and repair cycle is initiated. This cycle produces chronic beryllium disease (CBD), a progressive, fibrotic respiratory involvement which eventually suffocates exposed individuals. ^ Beryllium disease is an occupational disease, and as such it can be prevented by limiting exposures. In the 1940s journalists reported beryllium deaths at Atomic Energy Commission (AEC) facilities, the Department of Energy's (DOE) predecessor organization. These reports energized public pressure for exposure limits, and in 1949 AEC implemented a 2 μg/m3 permissible exposure limit (PEL). ^ The limits appeared to stop acute disease. In contrast, CBD has a long latency period between exposure and diagnosable disease, between one and thirty years. The lack of immediate adverse health consequences masked the seriousness of chronic disease and pragmatically removed CBD from AEC/DOE's political concern. ^ Presently the PEL for beryllium at DOE sites remains at 2 μg/m 3. This limit does not prevent CBD. This conclusion has long been known, although denied until recently. In 1999 DOE acknowledged the limit's ineffectiveness in its federal regulation governing beryllium exposure, 10 CFR 850. ^ Despite this admission, the PEL has not been reduced. The beryllium manufacturer and AEC/DOE have a history of exerting efforts to maintain and protect the status quo. Primary amongst these efforts has been creation and promotion of disinformation within peer reviewed health literature which discusses beryllium, exposures, health effects and treatment, and targeting graduate school students so that their perspective is shaped early. ^ Once indoctrinated with incorrect information, professionals tend to overlook aerosol and respiratory mechanics, immunologic and carcinogenic factors. They then apply tools and perspectives derived from the beryllium manufacturer and DOE's propaganda. Conclusions drawn are incorrect. The result is: health research and associated policy is conducted with incorrect premises. Effective disease management practices are not implemented. ^ Public health protection requires recognition of the disinformation and its implications. When disinformation is identified, then effective health policies and practices can be developed and implemented. ^
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Repeated treatment with psychostimulants produces behavioral sensitization that results in increased locomotor responses so that lower drug doses are required to obtain the same effect and cross-sensitization with other stimulants. Methylphenidate (MPD; Ritalin) is most frequently prescribed to treat children having attention deficit hyperactivity disorder (ADHD), a syndrome with onset in childhood characterized by high levels of inattention, hyperactivity, and impulsivity. Little is known of the consequences involving the long-term use of MPD as treatment for ADHD. This study investigates if there are age, genetic/strain, and sex differences in the prolonged exposure to MPD and cross-sensitization with amphetamine. The objective is to determine whether (a) early exposure to MPD in adolescent rats increases their sensitivity to the drug when they are adult rats, (b) there are strain and sex differences in the response to MPD, and (c) treatment with MPD in adolescent and adult Wistar-Kyoto (WKY), spontaneously hyperactive/hypertensive rat (SHR), and Sprague-Dawley (SD) rat results in cross-sensitization with amphetamine. The hypotheses are that (1) early exposure to MPD in adolescent rats increases their sensitivity to the drug when they reach adulthood, and that this hypersensitivity is dose-, strain-, and sex-dependent and (2) adult rats treated with MPD as adolescents will show a greater cross-sensitization to amphetamine than those adult rats treated with saline as adolescents, and that this cross-sensitization is dose-, strain-, and sex-dependent. The study consists of recording and evaluating locomotor activity of female and male WKY, SHR, and SD rats before and after acute and repeated MPD administration when these rats are young and as adults follows by an amphetamine treatment. Results showed that repeated treatment with MPD elicited behavioral sensitization and cross-sensitization with amphetamine in these animals. The study also found that strain and sex play a crucial role in the differentiated sensitivity to the acute and chronic effects of MPD. The development of behavioral sensitization and cross-sensitization are also dependent on the dose of MPD and the age of the rat. ^
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When compared to other types of occupational injuries, radiation overexposure events are somewhat rare, so health care providers may not be familiar with the actual clinical care to be provided when such an event occurs. Radiation overexposure treatment decisions are predicated on the amount of radiation dose received, which is a value many health care providers may not have the knowledge or expertise to either calculate or even estimate. Even the different units of measure for radiation exposure and dose received can be a source of confusion. The prompt treatment of radiation overexposure victims could be enhanced and facilitated through the creation of a single, simple protocol that consists of the various means of dose measurement and estimation, correlated to the corresponding appropriate clinical care measures. This culminating experience will assemble essential information currently maintained in disparate references to create a single, simplified protocol to facilitate the treatment of victims of acute external radiation overexposure. ^
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Background. In the United States, the incidence of pancreatic cancer has increased; more than 37,000 new cases of pancreatic cancer were diagnosed in the year 2007. Overall, the five-year survival rate is about 5% and pancreatic cancer ranks the fourth leading cause of cancer-related mortality among men and women. Despite the observed progress in cancer diagnosis and treatment, pancreatic cancer remains an unresolved significant public health problem in the United States. Familial pancreatic cancer has been confirmed to be responsible for approximately 10% of pancreatic cancer cases. However, 90% are still without known inherited predisposition. Until now, the role of oral contraceptive pills (OCPs) and hormonal replacement therapy (HRT) among women with pancreatic cancer remain unclear. We examined the association of exogenous hormonal uses in US women with risk of pancreatic cancer. ^ Methods. This was an active hospital-based case-control study which is conducted at the department of gastrointestinal medical oncology in The University of Texas M.D. Anderson Cancer Center. Between January 2005 and December 2007, a total of 287 women with pathologically confirmed pancreatic cancer (cases) and 287 healthy women (controls) were included in this investigation. Both cases and controls were frequency matched by age and race. Information about the use of hormonal contraceptives and hormonal replacement therapy (HRT) preparations as well as information about several risk factors of pancreatic cancer were collected by personal interview. Univariate and multivariate analyses were performed in this study to analyze the data. ^ Results. We found a statistical significant protective effect for use of exogenous hormone preparations on pancreatic cancer development (adjusted odds ratio [AOR], 0.4; 95% confidence interval [CI], 0.2–0.8). In addition, a 40% reduction in pancreatic cancer risk was observed among women who ever used any of the contraceptive methods including oral contraceptive pills (AOR, 6; 95% CI, 0.4–0.9). ^ Conclusions. Consistent with previous studies, the use of exogenous hormone preparations including oral contraceptive pills may confers a protective effect for pancreatic cancer development. More studies are warranted to explore for the underlying mechanism of such protection.^
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Patients who had started HAART (Highly Active Anti-Retroviral Treatment) under previous aggressive DHHS guidelines (1997) underwent a life-long continuous HAART that was associated with many short term as well as long term complications. Many interventions attempted to reduce those complications including intermittent treatment also called pulse therapy. Many studies were done to study the determinants of rate of fall in CD4 count after interruption as this data would help guide treatment interruptions. The data set used here was a part of a cohort study taking place at the Johns Hopkins AIDS service since January 1984, in which the data were collected both prospectively and retrospectively. The patients in this data set consisted of 47 patients receiving via pulse therapy with the aim of reducing the long-term complications. ^ The aim of this project was to study the impact of virologic and immunologic factors on the rate of CD4 loss after treatment interruption. The exposure variables under investigation included CD4 cell count and viral load at treatment initiation. The rates of change of CD4 cell count after treatment interruption was estimated from observed data using advanced longitudinal data analysis methods (i.e., linear mixed model). Using random effects accounted for repeated measures of CD4 per person after treatment interruption. The regression coefficient estimates from the model was then used to produce subject specific rates of CD4 change accounting for group trends in change. The exposure variables of interest were age, race, and gender, CD4 cell counts and HIV RNA levels at HAART initiation. ^ The rate of fall of CD4 count did not depend on CD4 cell count or viral load at initiation of treatment. Thus these factors may not be used to determine who can have a chance of successful treatment interruption. CD4 and viral load were again studied by t-tests and ANOVA test after grouping based on medians and quartiles to see any difference in means of rate of CD4 fall after interruption. There was no significant difference between the groups suggesting that there was no association between rate of fall of CD4 after treatment interruption and above mentioned exposure variables. ^
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This study has evaluated the utility of measuring effects of low level occupational exposure of nursing personnel to antineoplastic agents. The effect measured in this study is chromosomal damage in peripheral lymphocytes (chromosomal breakage and micronuclei frequency).^ Using nursing personnel in three exposure classifications (low, moderate and high) and breast cancer patients before and after treatment with antineoplastic agents, a weak but statistically significant association was found between exposure and chromosomal damage. Of special interest was the finding that consistent glove usage was negatively associated with increased chromosomal damage.^ The study also demonstrated a statistically significant association between the two measures of chromosomal damage: chromosomal breakage and micronuclei frequency. This suggests that the micronucleus method is a useful test for studying cytogenetic effects in lymphocytes. ^
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Studies have demonstrated a variable response to ozone among individuals and animal species and strains. For instance, C57BL/6J mice have a greater inflammatory response to ozone exposure than C3H/HeJ mice. In these studies, I utilized these strain differences in an effort to derive a mechanistic explanation to the variable strain sensitivity to ozone exposure. Therefore, alveolar macrophages (AM) from C57BL/6J and C3H/HeJ mice were exposed in vitro to hydrogen peroxide ($\rm H\sb2O\sb2$), heat and acetyl ceramide or in vivo to ozone. Necrosis and DNA fragmentation in macrophages from the two murine strains were determined to assess cytotoxicity following these treatments. In addition, synthesis and expression of the stress proteins, stress protein 72 (SP72) and heme oxygenase (HO-1), were examined following treatments. The in vitro experiments were conducted to eliminate the possibility of in vivo confounders (i.e., differences in breathing rates in the two strains) and thus directly implicate some inherent difference between cells from the two murine strains. $\rm H\sb2O\sb2$ and heat caused greater cytotoxicity in AM from C57BL/6J than C3H/HeJ mice and DNA fragmentation was a particularly sensitive indicator of cell injury. Similarly, AM from C57BL/6J mice were more sensitive to ozone exposure than cells from C3H/HeJ mice. Exposure to either 1 or 0.4 ppm ozone caused greater cytotoxicity in macrophages from C57BL/6J mice compared to macrophages from C3H/HeJ mice. The increased sensitivity of AM to injury was associated with decreased synthesis and expression of stress proteins. AM from C57BL/6J mice synthesized and expressed significantly less stress proteins in response to heat and ozone than AM from C3H/HeJ mice. Heat treatment resulted in greater synthesis and expression of SP72. In addition, macrophages from C57BL/6J mice expressed lower amounts of HO-1 than macrophages from C3H/HeJ mice following 0.4 ppm ozone exposure. Therefore, AM from C57BL/6J mice are more susceptible to oxidative injury than AM from C3H/HeJ mice which might be due to differential expression of stress proteins in these cells. ^
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Purpose. To describe the prevalence of violence exposure and depression and their association among 5th grade students. ^ Methods.. Students (n=5,147) attending 5th grade (mean age 11.12) from three major metropolitan areas in the United States were surveyed on various health-related measures including experience with being a victim of violence (adapted from YRBS and Traumatic Events Screening Inventory) and depressive symptoms (from the DISC Predictive Scale). Prevalence was calculated for rates of violence exposure as well as depression defined as having five or more depressive symptoms. Logistic regression was used to examine the association between exposure to violence and depression. ^ Results. This study found that over 35% of students were exposed to some form of violence such as being threatened, hit, punched, kicked, beaten up, or threatened/injured with a gun or knife. Male students had a higher prevalence than female students on almost all exposure types. Over 7% of students also reported having 5 or more depressive symptoms. All forms of violence were significantly associated with depression. Students who had been a victim of violence were between 2.5 and 6.5 more likely to have five or more depression symptoms. Conslusion. The results of this study underscore the urgent need of collaborative prevention and treatment efforts for children exposed to violence. By preventing such exposure, serious effects including physical injury, mental health problems, and other detrimental outcomes may be mitigated.^
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Objective. To review professional literature regarding treatment modalities of post-traumatic stress disorder (PTSD) amongst female Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) veterans, to assess the efficacy of these treatment options, and to summarize implications of the findings from this literature. Design. Systematic review of published literature. Data sources. Medline, Pubmed, Psycinfo. Review Methods. Articles selected for the literature review pertain to the treatment options of female OIF or OEF veterans who have a diagnosis of PTSD. In addition, other relevant articles, such as articles that discuss the prevalence of the problem, access to care, and similar treatment modalities for PTSD in other war settings, were selected for background information for the review. Results. The search strategy identified 1,305 potential journal articles, taken from thorough searches in Medline, Pubmed, and Psycinfo. These articles were then imported into Refworks. Following final screening, there were 18 articles included in the systematic review and 28 articles used as background information. The remaining articles were excluded following screening of abstract and/or full text of articles. Treatment modalities presented in these trials include: Exposure Therapy (average of 68% reduction in PTSD symptoms), Imagery Rehearsal Therapy (23% reduction), Body-Oriented Therapy (57% reduction), Electroconvulsive Therapy (35% reduction), Holographic Reprocessing (47% reduction), a self-defense training program (13% reduction), Cognitive Behavioral Therapy (65% reduction) and a variety of pharmacotherapies (antipsychotics at 81% reduction, sympatholytic drug at 100% reduction). Outcomes of the studies included in this systematic review were measured by using personal assessment of whether there was a reduction in symptoms of PTSD, based on the results in each study. Conclusion. Overall, all of the treatment modalities investigated in the systematic review proved to be somewhat effective in relieving the burden of symptoms of PTSD amongst female veterans of OIF/OEF. In addition to pharmacotherapy, which had the highest reduction in PTSD symptoms, both the Exposure Therapy and the Cognitive Behavioral Therapy techniques proved to have the most positive results. As all of the therapies had a positive effect on this population, to some degree, a study needs to be done in the future to compare and contrast the efficacy of each therapy intervention when applied to a standardized population.^