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Obesity and prostate cancer-specific mortality after radical prostatectomy: results from the Shared Equal Access Regional Cancer Hospital (SEARCH) database.
BackgroundAt the population level, obesity is associated with prostate cancer (PC) mortality. However, few studies analyzed the associations between obesity and long-term PC-specific outcomes after initial treatment.MethodsWe conducted a retrospective analysis of 4268 radical prostatectomy patients within the Shared Equal Access Regional Cancer Hospital (SEARCH) database. Cox models accounting for known risk factors were used to examine the associations between body mass index (BMI) and PC-specific mortality (PCSM; primary outcome). Secondary outcomes included biochemical recurrence (BCR) and castration-resistant PC (CRPC). BMI was used as a continuous and categorical variable (normal <25âkg/m2, overweight 25-29.9âkg/m2 and obese â©Ÿ30âkg/m2). Median follow-up among all men who were alive at last follow-up was 6.8 years (interquartile range=3.5-11.0). During this time, 1384 men developed BCR, 117 developed CRPC and 84 died from PC. Hazard ratios were analyzed using competing-risks regression analysis accounting for non-PC death as a competing risk.ResultsOn crude analysis, higher BMI was not associated with risk of PCSM (P=0.112), BCR (0.259) and CRPC (P=0.277). However, when BMI was categorized, overweight (hazard ratio (HR) 1.99, P=0.034) and obesity (HR 1.97, P=0.048) were significantly associated with PCSM. Obesity and overweight were not associated with BCR or CRPC (all Pâ©Ÿ0.189). On multivariable analysis adjusting for both clinical and pathological features, results were little changed in that obesity (HR=2.05, P=0.039) and overweight (HR=1.88, P=0.061) were associated with higher risk of PCSM, but not with BCR or CRPC (all Pâ©Ÿ0.114) with the exception that the association for overweight was no longer statistical significant.ConclusionsOverweight and obesity were associated with increased risk of PCSM after radical prostatectomy. If validated in larger studies with longer follow-up, obesity may be established as a potentially modifiable risk factor for PCSM
Impact of spouse caregiving on health behaviors and physical and mental health status
The impact of caring for a spouse with a progressive dementia on caregiver's health behaviors and health status was examined. Data collected from 44 spouse caregivers indicates that: âą Providing full-time care interferes with preventive health behaviors (eating nutritiously, exercising) and contributes to high risk behaviors (overeating, alcohol and substance use); âą Health behaviors are frequently used as coping strategies; âą Caregivers rated their own health as poorer than their spouse's health; and âą Disabling (arthritis, cardiac and back problems) and stress-related health problems (migraines, colitis) are a consequence of and interfere with care provision.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68204/2/10.1177_153331759400900105.pd
Risk Factors for Abdominal Wound Dehiscence in Children: A Case-Control Study
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81635.pdf (publisher's version ) (Closed access)BACKGROUND: In the limited literature concerning abdominal wound dehiscence after laparotomy in children, reported incidences range between 0.2-1.2% with associated mortality rates of 8-45%. The goal of this retrospective case-control study was to identify major risk factors for abdominal wound dehiscence in the pediatric population. METHODS: Patients younger than aged 18 years who developed abdominal wound dehiscence in three pediatric surgical centers during the period 1985-2005 were identified. For each patient with abdominal wound dehiscence, four controls were selected by systematic random sampling. Patients with (a history of) open abdomen treatment or abdominal wound dehiscence were excluded as control subjects. Putative relevant patient-related, operation-related, and postoperative variables for both cases and control subjects were evaluated in univariate analyses and subsequently entered in multivariate stepwise logistic regression models to identify major independent predictors of abdominal wound dehiscence. RESULTS: A total number of 63 patients with abdominal wound dehiscence and 252 control subjects were analyzed. Mean presentation of abdominal wound dehiscence was at postoperative day 5 (range, 1-15) and overall mortality was 11%. Hospital stay was significantly longer (p < 0.001) in the case group (median, 42 vs. 10 days). Major independent risk factors for abdominal wound dehiscence were younger than aged 1 year, wound infection, median incision, and emergency surgery. Incisional hernia was reported in 12% of the patients with abdominal wound dehiscence versus 3% in the control group (p = 0.001). CONCLUSIONS: Abdominal wound dehiscence is a serious complication with high morbidity and mortality. Median incisions should be avoided whenever possible
GAPscreener: An automatic tool for screening human genetic association literature in PubMed using the support vector machine technique
<p>Abstract</p> <p>Background</p> <p>Synthesis of data from published human genetic association studies is a critical step in the translation of human genome discoveries into health applications. Although genetic association studies account for a substantial proportion of the abstracts in PubMed, identifying them with standard queries is not always accurate or efficient. Further automating the literature-screening process can reduce the burden of a labor-intensive and time-consuming traditional literature search. The Support Vector Machine (SVM), a well-established machine learning technique, has been successful in classifying text, including biomedical literature. The GAPscreener, a free SVM-based software tool, can be used to assist in screening PubMed abstracts for human genetic association studies.</p> <p>Results</p> <p>The data source for this research was the HuGE Navigator, formerly known as the HuGE Pub Lit database. Weighted SVM feature selection based on a keyword list obtained by the two-way z score method demonstrated the best screening performance, achieving 97.5% recall, 98.3% specificity and 31.9% precision in performance testing. Compared with the traditional screening process based on a complex PubMed query, the SVM tool reduced by about 90% the number of abstracts requiring individual review by the database curator. The tool also ascertained 47 articles that were missed by the traditional literature screening process during the 4-week test period. We examined the literature on genetic associations with preterm birth as an example. Compared with the traditional, manual process, the GAPscreener both reduced effort and improved accuracy.</p> <p>Conclusion</p> <p>GAPscreener is the first free SVM-based application available for screening the human genetic association literature in PubMed with high recall and specificity. The user-friendly graphical user interface makes this a practical, stand-alone application. The software can be downloaded at no charge.</p
Mitochondrial chaotic dynamics: Redox-energetic behavior at the edge of stability
Mitochondria serve multiple key cellular functions, including energy generation, redox balance, and regulation of apoptotic cell death, thus making a major impact on healthy and diseased states. Increasingly recognized is that biological network stability/instability can play critical roles in determining health and disease. We report for the first-time mitochondrial chaotic dynamics, characterizing the conditions leading from stability to chaos in this organelle. Using an experimentally validated computational model of mitochondrial function, we show that complex oscillatory dynamics in key metabolic variables, arising at the âedgeâ between fully functional and pathological behavior, sets the stage for chaos. Under these conditions, a mild, regular sinusoidal redox forcing perturbation triggers chaotic dynamics with main signature traits such as sensitivity to initial conditions, positive Lyapunov exponents, and strange attractors. At the âedgeâ mitochondrial chaos is exquisitely sensitive to the antioxidant capacity of matrix Mn superoxide dismutase as well as to the amplitude and frequency of the redox perturbation. These results have potential implications both for mitochondrial signaling determining health maintenance, and pathological transformation, including abnormal cardiac rhythms.publishedVersionKembro, Jackelyn Melissa. Universidad Nacional de CĂłrdoba. Facultad de Ciencias Exactas, FĂsicas y Naturales; Argentina.Kembro, Jackelyn Melissa. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de Investigaciones BiolĂłgicas y TecnolĂłgicas; Argentina.Cortassa, Sonia. National Institutes of Health. NIH · NIA Intramural Research Program; Estados Unidos.Lloyd, David. Cardiff University. School of Biosciences 1; Inglaterra.Sollot, Steven. Johns Hopkins University. Laboratory of Cardiovascular Science; Estados Unidos.Sollot, Steven. Johns Hopkins University. Laboratory of Cardiovascular Science; Estados Unidos
Cross-Talk between the Cellular Redox State and the Circadian System in Neurospora
The circadian system is composed of a number of feedback loops, and multiple feedback loops in the form of oscillators help to maintain stable rhythms. The filamentous fungus Neurospora crassa exhibits a circadian rhythm during asexual spore formation (conidiation banding) and has a major feedback loop that includes the FREQUENCY (FRQ)/WHITE COLLAR (WC) -1 and -2 oscillator (FWO). A mutation in superoxide dismutase (sod)-1, an antioxidant gene, causes a robust and stable circadian rhythm compared with that of wild-type (Wt). However, the mechanisms underlying the functions of reactive oxygen species (ROS) remain unknown. Here, we show that cellular ROS concentrations change in a circadian manner (ROS oscillation), and the amplitudes of ROS oscillation increase with each cycle and then become steady (ROS homeostasis). The ROS oscillation and homeostasis are produced by the ROS-destroying catalases (CATs) and ROS-generating NADPH oxidase (NOX). cat-1 is also induced by illumination, and it reduces ROS levels. Although ROS oscillation persists in the absence of frq, wc-1 or wc-2, its homeostasis is altered. Furthermore, genetic and biochemical evidence reveals that ROS concentration regulates the transcriptional function of WCC and a higher ROS concentration enhances conidiation banding. These findings suggest that the circadian system engages in cross-talk with the cellular redox state via ROS-regulatory factors
Soil water content effects on net ecosystem CO2 exchange and actual evapotranspiration in a Mediterranean semiarid savanna of Central Chile
Biosphere-atmosphere water and carbon fluxes depend on ecosystem structure, and their magnitudes
and seasonal behavior are driven by environmental and biological factors. We studied the seasonal
behavior of net ecosystem CO2 exchange (NEE), Gross Primary Productivity (GPP), Ecosystem
Respiration (RE), and actual evapotranspiration (ETa) obtained by eddy covariance measurements
during two years in a Mediterranean Acacia savanna ecosystem (Acacia caven) in Central Chile. The
annual carbon balance was â53 g C mâ2 in 2011 and â111 g C mâ2 in 2012, showing that the ecosystem
acts as a net sink of CO2, notwithstanding water limitations on photosynthesis observed in this
particularly dry period. Total annual ETa was of 128 mm in 2011 and 139 mm in 2012. Both NEE and ETa
exhibited strong seasonality with peak values recorded in the winter season (July to September), as a
result of ecosystem phenology, soil water content and rainfall occurrence. Consequently, the maximum
carbon assimilation rate occurred in wintertime. Results show that soil water content is a major driver
of GPP and RE, defining their seasonal patterns and the annual carbon assimilation capacity of the
ecosystem, and also modulating the effect that solar radiation and air temperature have on NEE
components at shorter time scales.This work was funded by FONDECYT projects 1120713 and 1170429, a grant from the Inter-American Institute
for Global Change Research (IAI) [grant number CRN3056], which is supported by the US National Science
Foundation [grant number GEO-1128040], and the Spanish Ministry of Economy and Competitiveness project
GEI Spain (CGL2014-52838-C2-1-R), including ERDF founds. F. Bravo-MartĂnez is grateful to CONICYT for the
grants âFormaciĂłn de Capital Humano Avanzado-2009âČâČ, âBeca de Apoyo al tĂ©rmino de la tesis doctoral-2012âČâČ,
and CORFO INNOVA Grant N° 09CN14-5704. We thank to Enrique PĂ©rez Sanchez-Cañete and Borja RuĂz-
Reverter for technical support. We also thank âCODELCOâDivisiĂłn Andinaâ for use of the site. C. Montes
acknowledges the NASA Postdoctoral Program and to Universities Space Research Association
A likelihood ratio approach for utilizing case-control data in the clinical classification of rare sequence variants: Application to BRCA1 and BRCA2
A large number of variants identified through clinical genetic testing in disease susceptibility genes are of uncertain significance (VUS). Following the recommendations of the American College of Medical Genetics and Genomics (ACMG) and Association for Molecular Pathology (AMP), the frequency in case-control datasets (PS4 criterion) can inform their interpretation. We present a novel case-control likelihood ratio-based method that incorporates gene-specific age-related penetrance. We demonstrate the utility of this method in the analysis of simulated and real datasets. In the analysis of simulated data, the likelihood ratio method was more powerful compared to other methods. Likelihood ratios were calculated for a case-control dataset of BRCA1 and BRCA2 variants from the Breast Cancer Association Consortium (BCAC) and compared with logistic regression results. A larger number of variants reached evidence in favor of pathogenicity, and a substantial number of variants had evidence against pathogenicity findings that would not have been reached using other case-control analysis methods. Our novel method provides greater power to classify rare variants compared with classical case-control methods. As an initiative from the ENIGMA Analytical Working Group, we provide user-friendly scripts and preformatted Excel calculators for implementation of the method for rare variants in BRCA1, BRCA2, and other high-risk genes with known penetrance
The role of power in financial statement fraud schemes
In this paper, we investigate a large-scale financial statement fraud to better understand the process by which individuals are recruited to participate in financial statement fraud schemes. The case reveals that perpetrators often use power to recruit others to participate in fraudulent acts. To illustrate how power is used, we propose a model, based upon the classical French and Raven taxonomy of power, that explains how one individual influences another individual to participate in financial statement fraud. We also provide propositions for future research
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