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31.
The introduction of multidrug therapy by the World Health Organization has dramatically reduced the world prevalence of leprosy but the disease is still a public health problem in many countries, with a world prevalence of almost 600,000 cases in 2001. Damage to peripheral nerves is a key component of leprosy and the sensory and motor loss that follows is the basis for many of the classical features of this disease, such as skin wounds, cracks, plantar ulcers, clawed hands, drop foot, and incomplete closure of the eyelids. One of the most remarkable aspects of leprosy to lay persons and health care workers alike is that patients are reputed to feel no pain. However, neuropathic pain is arising as a major problem among leprosy patients. It can be nociceptive due to tissue inflammation, which mostly occurs during episodes of immune activation or neuropathic due to damage or dysfunction of the nervous system. This study, conducted among 358 leprosy patients, reveals a considerable prevalence of neuropathic pain and presents evidence that this common problem should be a high priority of those in charge of leprosy control programs.  相似文献   
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Analysis of genome-wide association studies with longitudinal data using standard procedures, such as linear mixed model (LMM) fitting, leads to discouragingly long computation times. There is a need to speed up the computations significantly. In our previous work (Sikorska et al: Fast linear mixed model computations for genome-wide association studies with longitudinal data. Stat Med 2012; 32.1: 165–180), we proposed the conditional two-step (CTS) approach as a fast method providing an approximation to the P-value for the longitudinal single-nucleotide polymorphism (SNP) effect. In the first step a reduced conditional LMM is fit, omitting all the SNP terms. In the second step, the estimated random slopes are regressed on SNPs. The CTS has been applied to the bone mineral density data from the Rotterdam Study and proved to work very well even in unbalanced situations. In another article (Sikorska et al: GWAS on your notebook: fast semi-parallel linear and logistic regression for genome-wide association studies. BMC Bioinformatics 2013; 14: 166), we suggested semi-parallel computations, greatly speeding up fitting many linear regressions. Combining CTS with fast linear regression reduces the computation time from several weeks to a few minutes on a single computer. Here, we explore further the properties of the CTS both analytically and by simulations. We investigate the performance of our proposal in comparison with a related but different approach, the two-step procedure. It is analytically shown that for the balanced case, under mild assumptions, the P-value provided by the CTS is the same as from the LMM. For unbalanced data and in realistic situations, simulations show that the CTS method does not inflate the type I error rate and implies only a minimal loss of power.  相似文献   
34.
After bone marrow transplantation (BMT), a prolonged dysregulation of humoral immunity can be observed. In the present study, we investigated whether this is reflected in an abnormal production of specific antibodies (Ab) to the T-cell-dependent recall antigen tetanus-toxoid (TT). The study group consisted of children receiving transplants of an unmodified allogeneic graft and of adults receiving either a T-cell- depleted allogeneic or an unmodified autologous BM graft. Findings were compared with those in healthy controls. In pediatric graft recipients, who were routinely revaccinated early after BMT, the Ab response was quantitatively superior to that in adult graft recipients who did not receive early revaccination. In the majority of graft recipients, the time period after vaccination required to reach the peak level of antibodies was prolonged and the number of responding TT-specific B- cell clones was markedly decreased in comparison with controls. In controls, a low frequency of dominant B-cell clones may produce low quantities of homogeneous Ab components (H-Ab) against a heterogeneous background. However, in BM graft recipients, "overshooting" of Ab production by separate B-cell clones was observed, resulting in the development of H-Ab at a relatively high concentration. These abnormalities were present up to 10 years after BMT, irrespective of either the age of the recipient, the modulation of the graft, or the vaccination schedule used. It is hypothesized that the dysregulated Ab production is the consequence of activation of a restricted number of resting memory B cells, present in germinal centers, repopulating gradually after BMT. Our data show that routine revaccination early after BMT improves the humoral immune response. However, because of a clonally dysregulated Ab production, long-lasting qualitative defects may be present even after normalization of Ab titers.  相似文献   
35.

AIM:

qualitative study, which aimed to identify the barriers that influence nursing care practices related to the sexuality of women with gynecological and breast cancer.

METHODS:

the study was conducted with 16 professionals of the nursing area (nurses, nursing technicians and nursing assistants) from two sectors of a university hospital situated in the state of São Paulo, Brazil. The data was collected using semi-structured, in-depth individual interviews. All the interviews were recorded and the participants'' responses were identified and categorized using Content Analysis.

RESULTS:

three major themes were identified. These are as follows: 1) barriers related to the biomedical model; 2) barriers related to institutional dynamics and 3) barriers related to the social interpretations of sexuality.

CONCLUSIONS:

the results of this study showed that the systematized inclusion of this issue in nursing care routines requires changes in the health paradigm and in the work dynamic, as well as reflection on the personal values and social interpretations related to the topic. A major challenge is to divest sexuality of the taboos and prejudices which accompany it, as well as to contribute to the nursing team being more aware of the difficulties faced by women with gynaecological and breast cancer.  相似文献   
36.
The use of ketamine (Ket) as a pharmacological model of schizophrenia is an important tool for understanding the main mechanisms of glutamatergic regulated neural oscillations. Thus, the aim of the current study was to evaluate Ket‐induced changes in the average spectral power using the hippocampal quantitative electroencephalography (QEEG). To this end, male Wistar rats were submitted to a stereotactic surgery for the implantation of an electrode in the right hippocampus. After three days, the animals were divided into four groups that were treated for 10 consecutive days with Ket (10, 50, or 100 mg/kg). Brainwaves were captured on the 1st or 10th day, respectively, to acute or repeated treatments. The administration of Ket (10, 50, or 100 mg/kg), compared with controls, induced changes in the hippocampal average spectral power of delta, theta, alpha, gamma low or high waves, after acute or repeated treatments. Therefore, based on the alterations in the average spectral power of hippocampal waves induced by Ket, our findings might provide a basis for the use of hippocampal QEEG in animal models of schizophrenia.  相似文献   
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38.
Right ventricular involvement is a typical characteristic of Chagas' disease, and it has been described especially in the early stages of the disease. However, the role of right ventricular dysfunction in cardiac failure due to Chagas' cardiomyopathy has not been well established. Seventy-four patients with positive serology tests for Trypanosoma cruzi and Chagas' dilated cardiomyopathy characterized by left ventricular dilatation and systolic dysfunction were studied. Clinical history, physical exam, ECG, chest X-ray and Doppler echocardiogram with color flow mapping were obtained in all. Mean age was 47.5+/-12.9 and 51 were males (69%). Sixty-five patients (88%) were in NYHA functional classes I and II. Mild systolic dysfunction was present in 35 (47%) while in 18 (24%), dysfunction was moderate and in 21 (28%) it was severe. In 43 patients (58%), only the left ventricle was involved by echocardiographic criteria; the remaining 31 patients (42%) showed biventricular involvement. No patient had isolated involvement of the right ventricle. Greater dilation of the right ventricle was associated with larger diastolic (p<0.002) and systolic (p<0.001) diameters of the left ventricle. Systolic pulmonary artery pressure was obtained non-invasively in 54 patients. Pulmonary hypertension was associated with right ventricular dilation (p<0.005) and with systolic dysfunction of the left ventricle (p<0.001). In this group of patients with Chagas' dilated cardiomyopathy, right ventricular dysfunction was present when there was associated and significant involvement of the left ventricle and with higher levels of pulmonary pressure.  相似文献   
39.
BACKGROUND: The Valsalva maneuver is a simple and reliable test of parasympathetic heart control that can also be used as a trigger of cardiac arrhythmia. Few studies are available about the Valsalva maneuver in Chagas disease patients without cardiac involvement and their results are contradictory. In a cross-sectional study, we compared Chagas disease patients without cardiac involvement and normal individuals using the Valsalva maneuver in order to study the vagal cardiac control and the occurrence of cardiac arrhythmia in the early phase of Chagas disease. METHODS: Fifty-nine patients with Chagas disease without cardiac involvement and 37 controls were submitted to a carefully standardized Valsalva maneuver. Cardiac vagal control was assessed by the Valsalva ratio and the occurrence of cardiac arrhythmia was recorded and coded. RESULTS: The two groups were comparable in terms of left ventricular ejection fraction and left ventricular end-diastolic dimension. When compared to the control group, patients with Chagas disease had significantly lower Valsalva ratios (1.81+/-0.41 versus 2.01+/-0.41, P=0.017) which were not significantly correlated with age, left ventricular function or the presence of radiological esophageal abnormalities. Atrioventricular block (mainly 2nd degree Mobitz type I) occurred exclusively in Chagas disease patients (15,6%, P=0.021) and may indicate an early involvement of the AV node. Premature ventricular contraction was more frequent in Chagas disease patients (16.9% versus 8.1%, P=0.217), although the difference was not statistically significant. CONCLUSION: The Valsalva maneuver is a useful test to detect early vagal dysfunction in Chagas disease patients without cardiac involvement.  相似文献   
40.
Several studies reported the concerted and mutual communication between the prostate epithelium and stroma, which determines the final organ architecture and function, but gets awry in cancer. Deciphering the mechanisms involved in this communication is crucial to find new therapeutic strategies. HS sequesters a number of secreted growth factors and cytokines, controlling their bioavailability to the target cells, suggesting that HS is an important regulator of the extracellular matrix (ECM) and a key player in the cell-cell and cell-microenvironment communication during prostate morphogenesis and physiology. We propose that by controlling HS biosynthesis and sulfation pattern, as well as the cleavage of the HS chain and/or the shedding of proteoglycans, epithelial and stromal cells are able to precisely tune the availability of signaling molecules and modulate ligand-receptor interaction and intracellular signal transduction.  相似文献   
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