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HIV-associated nephropathy (HIV-N) is considered a distinctive disease, the pathogenesis of which is still undefined. Direct virus-induced renal cell damage has been postulated. The numerous cytolytic ultrastructural changes and a few studies by immunoperoxidase support this hypothesis, but there has been no demonstration of virus by electron-microscopy (EM) or by tissue culture. In seven out of 12 cases with histological characteristics of HIV nephropathy, with proteinuria (five cases) or with nephrotic syndrome (two cases), we tested renal tissue for HIV antigens: core p18 and p25; envelope gp45 and gp110, by means of immunoperoxidase avidin-biotin complex monoclonal antibodies (MoAbs). Light-microscopy (LM) showed in five patients a focal and segmental glomerular sclerosis, and in two a mesangial hyperplasia with vacuolisation of visceral epithelium and protein inclusions. Electron-microscopy, performed in five of seven patients, showed several protein inclusions in podocyte cytoplasm, tubuloreticular inclusions in endothelial cell cytoplasm in all cases, nuclear degranulation of tubular cells in four cases and nuclear bodies in two. HIV antigens by MoAbs on renal tissue were negative in all cases, in both glomeruli and tubules. These results do not confirm the presence of HIV proteins in renal tissue of patients with HIV nephropathy. A possible explanation, apart from no direct HIV in the disease, may be the low viral load in tissues, because of the early phases of renal damage in most cases.  相似文献   
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Patients with acquired immunodeficiency syndrome (AIDS) and persistent lymphadenopathy syndrome (LAS) display significant hematological abnormalities of one or more cell lineages. In order to understand the pathophysiologic mechanisms leading to these abnormalities we studied the proliferation capacity of pluripotent and committed hemopoietic precursors using in-vitro colony assays. Anemia, leukopenia and thrombopenia were relatively frequent findings in HIV-infected subjects irrespectively of the patients' clinical status. The colony growth capacity of AIDS patients' GM-CFU and BFU-E was significantly decreased whereas no GEMM-CFU colonies could be obtained. There was no correlation between the number of BFU-E and GM-CFU colony number and the hemoglobin or the absolute number of polynuclear cells, respectively. The plating efficiency of both committed and pluripotent hematopoietic precursors from HIV infected patients could not be enhanced when additional exogenous recombinant GM-CSF, human interleukin 3 or erythropoietin were added in contrast to normal patients' cells. In addition, the impaired colony growth of these precursors could not be restored after adherent or T-cell depletion or the addition of normal allogenic irradiated adherent or/and T cells. Since this colony growth abnormality was also detected in HIV seropositive asymptomatic subjects our findings strongly suggest that the in-vitro growth of hematopoietic precursors is affected early after HIV-1 infection.  相似文献   
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OBJECTIVE: There is a high comorbidity between symptoms of post-traumatic stress disorder (PTSD) and chronic pain incidence. The objective of this investigation was to determine the prevalence of PTSD symptoms in chronic orofacial pain patients. STUDY DESIGN: The study included 1478 adult patients (mean age 36.4 +/- 12.7 years) with primary diagnoses of masticatory/cervical muscle pain or temporomandibular joint pain. Patients completed a battery of psychometric questionnaires including a screening for PTSD symptoms. The sample was divided into a PTSD-positive group (n=218, 15%) a PTSD-negative group (n=551, 37%), and a no-stressor group (n=709, 48%) according to stressor incidence and symptom severity. RESULTS: The current prevalence of PTSD symptomatology was considerably higher than that reported in surveys from the general population. Patients in the PTSD-positive symptom group reported significantly higher psychological distress, sleep dysfunction, and pain severity compared to patients in the other groups. Psychological distress as measured by the SCL-90-R reached clinically significant levels only in those patients with PTSD symptomatology. CONCLUSIONS: The results of this study performed at a tertiary care center suggest that TMD patients without PTSD symptomatology show low levels of psychological distress, if any. Clinically significant levels of psychological distress are likely indicators for PTSD. PTSD screening should be included as part of a routine psychometric test battery in TMD patients.  相似文献   
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The effects of Captopril, an angiotensin-converting enzyme inhibitor, on pulmonary hemodynamics and blood gases were studied in 9 patients with chronic obstructive lung disease (COLD) and pulmonary hypertension (PA-P greater than 20 mm Hg). Hemodynamic data were recorded prior to Captopril administration (50 mg per os) and for the next 60 min. Following Captopril administration, significant reductions in mean pulmonary artery pressure (PA-P) (p less than 0.05), in mean pulmonary wedge pressure (PW-P) (p less than 0.05), and in total pulmonary resistance (TPR) were noted; significant reductions in mean brachial artery pressure (BA-P) and systemic vascular resistance (SVR) were also recorded, while cardiac output, heart rate and blood gas tensions showed no significant changes. Furthermore, the higher the hypoxemia, the greater was the reduction in BA-P (p less than 0.05). We therefore feel that Captopril, when administered to COLD patients with pulmonary hypertension, may protect the pulmonary circulation from hypoxic pulmonary vasoconstriction.  相似文献   
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The detection of monocytes in human glomerulonephritis   总被引:10,自引:0,他引:10  
Renal biopsy specimens from 343 patients with primary or secondary glomerulonephritis (GN) were examined for monocytes by the non-specific esterase reaction. Large numbers of monocytes per glomerulus (M/G) were found in essential cryoglobulinemia GN (29 pts, M/G 30.6 +/- 22.4), in acute post-infectious GN (27 pts, M/G 9.1 +/- 8.3), in rapidly progressive crescentic GN (20 pts, M/G 5.6 +/- 2.7), in systemic lupus GN (61 pts, M/G 5.0 +/- 5.6), and in IgA-GN associated with chronic liver disease (5 pts, M/G 6.4 +/- 5.9) or Sch?nlein-Henoch purpura (15 pts, M/G 3.3 +/- 6.4). Clinico-histological correlation showed that monocyte infiltration was correlated with the extent of proteinuria (all groups), with the presence of endoluminal "thrombi" (cryoglobulinemia GN), of polymorphonuclear leukocyte infiltration (post-infectious GN), of cellular crescents (crescentic GN), of "active" lesions (lupus GN), and with the extension of lesions to the peripheral capillary walls (IgA-associated GN). The M/G index was negligible in renal amyloidosis (21 pts), in idiopathic membranoproliferative GN (10 pts), in idiopathic IgA mesangial GN (63 pts), in membranous GN (40 pts), in focal glomerulosclerosis (29 pts), in minimal change nephropathy (18 pts), and in diabetic glomerulosclerosis (5 pts). The results confirm the participation of cells of the monocyte-macrophage series in the genesis of proliferative lesions, both intracapillary and extracapillary, in immune-mediated human GN and suggest their direct involvement in glomerular injury.  相似文献   
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Maternal and Child Health Journal - To study the relationship between cesarean Delivery (CD) and overweight in preschool children, considering the presence of birth aspects and demographic...  相似文献   
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Bisphenol A (BPA) is an organic chemical compound widely used for manufacturing plastics. BPA exposure originates principally from the diet, but it can also originate from dermal contact. In over 90% of individuals, including pregnant women, BPA is detectable in several body fluids. The effects of this exposure on the fetus are under active investigation in several research laboratories. The aim of our work was to study the impact of prenatal exposure to BPA in the liver of rat fetuses from a sex-dependent point of view. We particularly investigated the effects of prenatal BPA exposure on hepatic lipids because of their crucial role, not only for the liver, but also for the whole-body functions. Our results demonstrate that the liver of rat fetuses, in utero exposed to a very low dose of BPA (2.5 µg/kg/day), displays significant modulations with regard to proteins involved in cholesterol and fatty acid biosynthesis and trafficking. Moreover, an impact on inflammatory process has been observed. All these effects are dependent on sex, being observable only in female rat fetuses. In conclusion, this work demonstrates that maternal exposure to BPA compromises hepatic lipid metabolism in female offspring, and it also reveals the perspective impact of BPA on human health at doses currently considered safe.  相似文献   
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