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Introduction: The use of contralateral prophylactic mastectomy (CPM) continues to grow despite the absence of evidence supporting a survival benefit. This study's objectives were to (1) describe the trends in the rates of unilateral and bilateral mastectomy (BM) in women diagnosed with unilateral breast cancer (UBC) in Ontario, Canada from 1991 to 2013, and (2) identify factors associated with BM to treat UBC. Methods: This retrospective cohort analysis included all women aged 18 and older diagnosed with UBC between January 1991 and December 2013. Health administrative data from the Institute for Clinical Evaluative Sciences, the Ontario Cancer Registry, and the Discharge Abstract Database were used to identify all breast cancer and mastectomy cases. Age-adjusted mastectomy rates were plotted over time. Univariable and multivariable analyses included clinically significant covariates. Results: From 1991 to 2013 there were 172,165 cases of UBC and 64,886 mastectomies (37.7%) performed in Ontario. 13.6% of the mastectomies were bilateral. BM rates increased over sixfold (from 4 to 25%) across all age groups under age 70 over a 23-year period. On multivariable analysis, younger age, higher income, rural community, earlier breast cancer stage, lobular histology, availability of reconstruction and teaching hospitals were associated with increased odds of BM. Conclusions: This is the largest population study of breast cancer patients in Canada and shows an increasing rate of BM for UBC. The results are similar to those already described in the US and highlight the importance of continued efforts to promote efficient communication and evidence-based decision-making prior to breast surgery. [ABSTRACT FROM AUTHOR]

Background: The nonunion fracture is a relatively frequent complication in both human and veterinary medicine. Specifically, atrophic fracture nonunions are difficult to treat, with revision surgery usually providing the best prognosis. Anabolic steroids, such as nandrolone decanoate (ND), have been reported to have beneficial clinical effects on bone mass gain during osteoporosis; however, their utility in promoting regeneration in atrophic nonunions has not been documented. Our objective was to examine morphological changes induced by the ND in experimental fracture nonunion with vascular deficit in the rat model.Methods: Fourteen adult Wistar rats had an atrophic fracture nonunion induced in the diaphysis of their left femur. Rats were allocated into two groups: control group and nandrolone decanoate group. Rats in the latter group were given nandrolone decanoate (1.5 mg/kg IM, once a week, during 4 weeks after confirmation of fracture nonunion radiographically). Radiographic and anatomopathological examination, micro-tomography and histological analysis were assessed to characterize the morphological changes promoted by the nandrolone decanoate use.Results: Based on radiology, anatomopathological evaluation, computed micro-tomography and conventional microscopy, nandrolone decanoate promoted bone regeneration at the fracture nonunion site by increasing the cellularity at the fracture site. Percentage of collagen was not significantly different between groups, consistent with high-quality regenerated bone.Conclusion: The anabolic steroid nandrolone decanoate improved bone mass and regeneration without affecting collagen production and therefore has potential for improving outcomes for atrophic fracture nonunion. [ABSTRACT FROM AUTHOR]

Chemotherapy-induced mucositis is an important dose-limiting and costly side effect for which there is no definitive prophylaxis or treatment. This is due in part to the lack of understanding of its pathophysiology and impact on intestinal function. The objectives of this study were to investigate the small intestine barrier function and electrolyte and water transport in an experimental model of methotrexate-induced mucositis, and to correlate these alterations with histological damage. Wistar rats were treated with methotrexate (1.5-3.5 mg/kg) for 3 days to induce mucositis. Intestinal permeability was measured by the urinary excretion rate of lactulose and mannitol following administration by gavage. Intestinal perfusion was performed in vivo for evaluation of water and electrolyte transports. Methotrexate-treated rats lost a significant amount of weight and presented a marked reduction in food intake. Methotrexate induced significant and dose-dependent villous atrophy and elongation of crypts in duodenum, jejunum, and ileum. Methotrexate also induced an increase in sodium and potassium secretion and an important reduction of the mucosa absorptive surface area, shown by the decrease in the mannitol excretion ratio. In conclusion, methotrexate caused major changes in small bowel function by disrupting intestinal permeability and inducing electrolyte secretion in parallel with substantial histological damage. [ABSTRACT FROM AUTHOR]

Anti-neutrophil cytoplasmic antibodies (ANCA) are autoantibodies directed to intracellular components of neutrophils and are present in several vasculitic syndromes. Recently, these autoantibodies have been described in other autoimmune disorders as well as in infectious diseases such as tuberculosis (TB). As there are some clinical similarities between TB and granulomatosis with polyangiitis, we searched for ANCA in a group of patients with proven TB. Patients with TB confirmed by chest X-ray and sputum bacilloscopy either before or within 30 days after beginning treatment were included in this study. Anti-MPO and anti-PR3 antibodies were studied using well-standardized ELISA kits (INOVA Diagnostics, Inc.). ANCA were also investigated by indirect immunofluorescence (IIF). Fifty TB patients (26 females, mean age 47.34 ± 17 years) were enrolled in the present study. No patient tested positive for ANCA by IIF, or anti-MPO or anti-PR3 antibodies by ELISA. Although previous studies have shown the presence of ANCA in some infectious diseases, the findings of the present study demonstrated the absence of such antibodies in TB. The discrepancy in the prevalence of ANCA in TB among different studies may be attributed to methodological factors and/or the genetic background of the studied populations. [ABSTRACT FROM AUTHOR]

We investigate the spin-polarized transport of holes in GaMnAs/GaAs heterostructures with Mn concentration 5% in which a ferromagnetic order is known to exist. Disorder enters the problem both in the random distribution of Mn centers and impurities, and also in the orientation of the magnetic moments at the Mn sites. We take into account the existence of an impurity band determining the extended or localized nature of the states at and near the Fermi level. Magnetic order and resistivity are inter-related due to the influence of the spin polarization of the impurity band and the effect of the Zeeman splitting on the mobility edge. We obtain two channels of transport, one provided by the extended states above the mobility edge, when this lies below the Fermi level, the other coming out of the thermal excitation of the localized states through a hopping mechanism. We discuss the competition between these two channels in determining, once having obtained the dependence of the resistance on temperature, the metallic or non-metallic nature of the sample. [ABSTRACT FROM AUTHOR]

The aims of this study were to evaluate the expression of keratinocyte growth factor (KGF) in goat ovaries and to study its effects on preantral follicle survival and development. The ovaries were used for immunohistochemistry or for in vitro culture for 1 or 7 days with KGF (0, 1, 10, 50, 100, 150, or 200 ng/mL). Noncultured (fresh control) and cultured ovarian slices were processed for histological analysis and transmission electron microscopy (TEM). The results showed that after 7 days of in vitro culture, all treatments had a significant reduction in the percentage of normal follicles compared with the fresh control. After 7 days of culture, the highest KGF concentrations (150 and 200 ng/mL) induced a significant reduction in the percentage of normal follicles compared with the tissues cultured in the absence (α-MEM+ alone) or presence of 1, 10, and 50 ng/mL KGF. Transmission electron microscopy confirmed follicular integrity after 7 days of culture in 1 ng/mL KGF. In addition, compared with the fresh control, the percentage of growing follicles was significantly increased in all treatments after 1 or 7 days of culture. Immunohistochemical analyses showed the expression of KGF in oocytes and granulosa cells in all follicle developmental stages as well as in thecal and stromal cells. In conclusion, this study demonstrated that, at the lowest concentration (1 ng/mL), KGF maintained the ultrastructure of goat preantral follicles cultured in vitro for up to 7 days. Furthermore, the KGF protein was widely distributed in goat ovaries, especially in ovarian follicles. [ABSTRACT FROM PUBLISHER]

Synchrotron X-ray imaging systems with fluorescence techniques was developed for biomedical researches in Brazilian Synchrotron Laboratory. An X-ray fluorescence microtomography system was implemented to analyse human prostate and breast samples and an X-ray microfluorescence system was implemented to study bone sites of human and animal samples with and without bone disorders. [ABSTRACT FROM AUTHOR]

Several studies over the last decade have shown that tropical reservoirs may constitute an appreciable source of methane (CH4) to the atmosphere. Here, we show that the use of low-cost, innovative mitigation and recovery strategies is able not only to reduce these emissions, but also to transform existing biogenic methane stocks into a renewable energy source. Recovered gas may be pumped to large consuming centers or stored locally and burned by gas turbines to generate electricity during high-demand periods, or even purified for transport applications. Our analysis shows that the use of biogenic methane may increase considerably the energy supply in countries, like Brazil, which possess large tropical reservoirs. [ABSTRACT FROM AUTHOR]

A self-consistent calculation of the density of states and the spectral density function is performed in a two-dimensional spin-polarized hole system based on a multiple-scattering approximation. Using parameters corresponding to GaMnAs thin layers, a wide range of Mn concentrations and hole densities have been explored to understand the nature, localized or extended, of the spin-polarized holes at the Fermi level for several values of the average magnetization of the Mn system. If the impurity concentration is below a certain threshold, the increase of the magnetization does not lead to a significant change in the localized character of the spin-polarized states. Above this threshold, we reach conditions allowing the occurrence of spin-polarized extended states at the Fermi level—more properly extended states in a very dirty metal—which are very sensitive to the average magnetization. The occurrence of a metal-to-non-metal transition has been surveyed around an optimum combination of the Mn concentration and the free carriers density. [ABSTRACT FROM AUTHOR]

In what is a first for the world, leaf spot disease of sweet potato, caused by Boeremia exigua, is reported in Brazil. Identity of the fungus was confirmed by a combination of molecular and morphological data. Koch's postulates were fulfilled with a selected isolate of the fungus obtained from Santa Maria do Jetibá, state of Espírito Santo, Brazil. [ABSTRACT FROM AUTHOR]

One of the great 3D micro tomography (3D-mCT) applications in the medical area is the characterization of bone architecture, especially when it is spoken in osteoporosis because, among other factors, is characterized by the deterioration of the architecture. This work shows the 3D quantification, based on stereological concepts, of the bone tissue through 3D-mCT in real time. The analyses were carried out in femur rat and the 3D visualizations helped to understand bones morphology. The results showed the potential of this computational technique to verify the capability of characterization of the internal bone structures and the importance of the threshold level in the binarization process. [ABSTRACT FROM AUTHOR]

This paper describes an analytical method using a nuclear-related technique for the detection of forbidden doping substances in the urine of race horses. The proposed method, adapted from the Méthode Alcaline Sur C-18 developed by the French Laboratoire de Contrôle Antidopage, is based on gas chromatography separation followed by mass spectrometry (GC-MS). The method was validated for caffeine, identified as the most frequent doping substance in the Brazilian horseracing activity. This validation is also a major requirement to achieve ISO/IEC 17025 laboratory accreditation. The validation has led to several metrological challenges because the decisions are largely based on qualitative results (“false-positive” and/or “false-negative”) and the degree of accuracy, as well as the traceability had to be determined in the absence of certified matrix reference materials. [ABSTRACT FROM AUTHOR]

The serotonin transporter (5-HTT) is a candidate gene for bipolar disorder (BPD). It has been investigated for association with the illness in a series of studies, but overall results have been inconsistent and its role in the disorder remains controversial. Systematic reviews using meta-analytical techniques are a useful method for objectively and reproducibly assessing individual studies and generating combined results. We performed two meta-analyses of published studies—both population-based and family-based studies—investigating the association between BPD and the 5-HTT gene-linked polymorphic region (5-HTTLPR) and the intron 2 variable numbers of tandem repeats (VNTR) polymorphisms. The literature was searched using Medline and Embase to identify studies for inclusion. We statistically joined population-based and family-based studies into a single meta-analysis. For both polymorphisms, our review revealed significant pooled odds ratios (ORs): 1.12 (95% CI 1.03–1.21) for the 5-HTTLPR and 1.12 (95% CI 1.02–1.22) for the intron 2 VNTR. Meta-regression showed that neither the study type (population-based vs family-based; P=0.41 for the 5-HTTLPR and P=0.91 for the intron 2 VNTR) nor the sample ethnicity (Caucasian vs non-Caucasian; P=0.35 for the 5-HTTLPR and P=0.66 for the intron 2 VNTR) significantly contributed to the heterogeneity of the meta-analyses. The observed ORs could be regarded simply as a very small but detectable effect of the 5-HTT, which has an additive effect when combined with other susceptibility loci. Alternative hypotheses on this finding were also discussed: a stronger effect of the haplotypes involving the two polymorphisms or other SNP markers; a more direct effect of these polymorphisms on specific phenotypes of BPD; and the presence of gene–environment interaction as a mediator of the genetic effects of 5-HTT.Molecular Psychiatry (2005) 10, 771–781. doi:10.1038/sj.mp.4001663; published online 12 April 2005 [ABSTRACT FROM AUTHOR]

Wide parabolic wells can be created by properly controlling the Al content during the growth of successive Ga1− xAl xAs thin layers. Under a tilted magnetic field these systems present interesting transport properties, which are associated to their composition dependent g-factor. We present an exact solution for the eigenstates of an electron gas inside such a quantum well. We calculate the renormalized cyclotron frequencies as functions of the angle of tilt, as well as the density of states, and the Fermi level. We discuss the conditions for the existence of spin-polarized charge. [ABSTRACT FROM AUTHOR]

A self-consistent Luttinger–Kohn (LK) calculation is used to obtain the electronic structure of Mn-doped semiconductor multilayers. In the particular, case of a (In,Ga)As/GaAs heterostructure, the ternary alloy has a smaller gap than GaAs, and introduces strain due to the differences on the lattice parameters. The aim of this work is to understand how the charge and the spin polarization densities can be controlled by the parameters of the structure in such way that they appear concentrated either on the magnetic or in the non-magnetic region. We show that by changing the In concentration the valence band mismatch competes with the energy splitting due to the magnetic interaction, and we can manipulate the charge and the spin polarization densities in the structure. [ABSTRACT FROM AUTHOR]

It is shown that spin-polarized currents occur in metallic and ferromagnetic Ga1− xMn xAs/GaAs multilayered structures, as a result of the magnetic interaction between holes and the Mn ions. The magnetic layers act as potential barriers for holes with spins aligned parallel to the layer magnetization, and as potential wells for the inverse spin polarization. In the case of currents in-plane, holes with spin parallel and antiparallel to this magnetization move in different regions. By choosing properly the magnetic and the nonmagnetic layers widths, a spin-polarized transport with a difference of an order of magnitude on the mobilities for each spin polarization is predicted to occur. Spin-polarized minibands are also shown to occur in a superlattice based on the same structure. We calculated the dependence of the spin polarization with the superlattice parameters, and we discuss how this polarization affects the Bloch miniband transport in such ferromagnetic superlattice. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is an autoimmune disease characterized by symmetric polyarthritis, rheumatoid factor (RF) positivity, and bone erosions. Recently, research has been conducted on anti-citrullinated peptide antibodies (ACPAs) to which there are greater sensitivity and specificity than RF. However, these antibodies have also been described in infectious diseases, particularly tuberculosis (TB), placing the high specificity of the test in doubt. The aim of this research was to study the prevalence of ACPAs in TB, RA, and healthy controls. Patients with bacteriologically confirmed pulmonary tuberculosis, RA (ACR criteria), in addition to healthy controls were included. ACPAs were researched by: anti-cyclic citrullinated peptide (CCP), anti-modified citrullinated vimentin (MCV), and RF by ELISA. The study was conducted in 50 TB patients, 50 with RA, and 20 controls. Anti-CCP antibodies were found in 39 (78 %) of the RA patients (median titer, 128 U), whereas anti-MCV antibodies were found in 25 (50 %). Of the patients with TB, two (4 %) had positivity for anti-CCP and anti-MCV and no patient in the control group tested positive for these antibodies. Sensitivity of anti-CCP for RA was 78 % (confidence interval (CI), 63 to 88 %) and specificity was 97 % (CI, 89 to 99 %) while the sensitivity of anti-MCV was 50 % (CI, 35-64 %) and specificity was 97 % (CI, 89 to 99 %). RF was positive in 40 samples (80 %) of RA, in 30 (60 %) of TB, and in 1 (5 %) of the controls. Our findings showed high sensitivity of anti-CCP and high specificity of both anti-CCP and anti-MCV antibodies for RA, even in a population with high incidence of tuberculosis. The higher frequency of positivity of ACPA in TB observed in previous studies may be attributed to methodological factors. [ABSTRACT FROM AUTHOR]

Activation of the inflammatory response system has been observed in the schizophrenia and affective disorders. Investigations of the role of the inflammatory response in these psychiatric disorders include analysis of the immune mediators at the gene level, so the genetic polymorphism of specific cytokine loci has been investigated in psychiatric disorders. In the present investigation, researchers performed cross-sectional study to verify whether the G308A gene polymorphism was associated with a predisposition to schizophrenia or bipolar affective disorder (BPAD) in a Brazilian sample. A total of 657 controls were randomly recruited from unrelated subjects admitted to a routine checkup outpatient clinic. Results showed an association between the G308A TNF-α polymorphism and schizophrenia.

We present results for the single-particle relaxation time of the spin-polarized two-dimensional electron gas in Silicon-MOSFET systems at zero temperatures. Spin-polarization is produced by the application of a parallel magnetic field. The single-particle relaxation time was measured with the Shubnikovde–Hass effect and is in good agreement with our theoretical results. [ABSTRACT FROM AUTHOR]

Objective: To examine the impact of neighbourhood marginalization on avoidable mortality (AM) from preventable and treatable causes of death., Methods: All premature deaths between 1993 and 2014 (N = 691,453) in Ontario, Canada, were assigned to quintiles of neighbourhood marginalization using the four dimensions of the Ontario Marginalization Index: dependency, ethnic concentration, material deprivation, and residential instability. We conducted two multivariate logistic regressions to examine the association between neighbourhood marginalization, first with AM compared with non-AM as the outcome, and second with AM from preventable causes compared with treatable causes as the outcome. All models were adjusted for decedent age, sex, urban/rural location, and level of comorbidity., Results: A total of 463,015 deaths were classified as AM and 228,438 deaths were classified as non-AM. Persons living in the most materially deprived (OR, 1.24; 95% CI, 1.22 to 1.27) and residentially unstable neighbourhoods (OR, 1.13; 95% CI, 1.11 to 1.15) had greater odds of AM, particularly from preventable causes. Those living in the most dependent (OR, 0.91; 95% CI, 0.89 to 0.93) and ethnically concentrated neighbourhoods (OR, 0.93; 95% CI, 0.91 to 0.93) had lower odds of AM, although when AM occurred, it was more likely to arise from treatable causes., Conclusion: Different marginalization dimensions have unique associations with AM. By identifying how different aspects of neighbourhood marginalization influence AM, these results may have important implications for future public health efforts to reduce inequities in avoidable deaths.