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In breast milk and paired blood samples of nine HIV-1-infected lactating women, we undertook a study to detect a CD4 T-cell reservoir and to investigate its capacity to enter viral production after activation. Breast milk-infected CD4 T cells have a greater capacity to produce viral particles actively than blood CD4 T cells. This observation may explain the apparent paradox of a transmissible viral infection from a body fluid with a low viral concentration.  相似文献   
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BACKGROUND/AIMS: Iron deficiency impairs growth and psychomotor development of infants. In Morocco, infusions are introduced very early in infant diet, and could contribute to iron deficiency, due to their high polyphenol content. METHODS: The availability of tea, mint and vervain infusions was assessed using an in vitro model of digestion and dialysis. Two gastric pHs were used: pH 4 as in the first week life, and pH 2.5 as in older infants. Six repetitions of each experiment were made. The total polyphenol content of infusions was measured. RESULTS: At pH 4 and at pH 2.5, iron availability was decreased by tea and vervain, and increased by mint and ascorbic acid. At both pHs it was increased by addition of ascorbic acid to tea and vervain. In addition, at pH 2.5 it was increased by addition of ascorbic acid to mint. The highest value was observed in the presence of both ascorbic acid and mint (33.1 +/- 4.1%). In any case, iron availability was higher at pH 2.5 than at pH 4 (with single compounds or combinations with ascorbic acid). The polyphenol contents (mg/l) of tea, vervain and mint infusions were 2,236.1, 771.1, and 16.5. CONCLUSIONS: Tea and vervain infusions inhibited iron availability. In contrast, mint improved it; vitamin C helped in preventing these inhibiting properties. It could be proposed to discourage tea and vervain drinking at early weaning and to replace them by mint infusion, or at least to promote the consumption of vitamin C-rich fruit juice to counteract these inhibiting effects.  相似文献   
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Autoimmune mucocutaneous blistering diseases (AMBD) are a group of potentially fatal diseases that affect the skin and mucous membranes. AMBD have different target antigens as well as variable clinical presentation, course, and prognosis. The mainstay of conventional immunosuppressive therapy (CIST) for AMBD is long-term high-dose systemic corticosteroids and immunosuppressive agents. Such therapy has proven effective in many patients; however, in some patients, the disease continues to progress with significant sequelae such as blindness, loss of voice, anal, and vaginal stenosis which causes poor quality of life. Furthermore, the CIST may have some serious side effects including opportunistic infections which may cause death. Immune globulin intravenous (IGIV) therapy has been reportedly used in the management of patients with AMBD refractory to CIST. IGIV has shown to be more clinically beneficial than CIST by bringing about long-term clinical remission and less recurrence. The high cost of the IGIV is of concern to patients, physicians, and insurance companies. In this report, we compare the cost of IGIV to that of CIST in treating a cohort of 15 mucous membrane pemphigoid (MMP), 10 ocular cicatricial pemphigoid (OCP), 15 bullous pemphigoid (BP), and 32 pemphigus vulgaris (PV) patients. In each cohort of patients, CIST had significant side effects, many of which were hazardous and required prolonged and frequent hospitalizations. Some of these side effects were severe enough to require discontinuation of the treatment. We consider the total cost of CIST to be the actual cost of the drug, plus the cost of management of the side effects produced by CIST. In the same patient cohort, no significant side effects to IGIV were observed. None of the IGIV treated patients required physician visits, laboratory tests, or hospitalizations specifically related to IGIV therapy. Hence, the total cost of the IGIV therapy is the actual cost of the IGIV only. The mean total cost of treatment of IGIV therapy is statistically significantly less than that of CIST during the entire course of the disease and on an annual basis. In conclusion, IGIV therapy is a safe, clinically beneficial, and a cost effective alternative treatment in patients with AMBD, non-responsive to CIST.  相似文献   
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The subthalamic nucleus is a key structure for motor information processing in the basal ganglia. Little is known about its involvement in other aspects of behavior such as motivation. We investigated neuronal activity in the subthalamic nucleus while a monkey performed arm-reaching movements to obtain a liquid reward. Most neurons were modulated both during the movement and reward phases of the task. The changes in activity occurring after or just before the delivery of reward consisted of either increases or decreases in firing and were not directly related to mouth movements. These findings indicate that STN neurons are involved in the detection and expectation of reward, consistent with a role for these neurons in the processing of motivational information.  相似文献   
347.
The aim of this study was to assess the efficacy and morbidity of endoscopic variceal ligation for the prophylaxis of rebleeding from oesophageal varices. This work is a prospective study including 102 patients having had at least one episode of variceal bleeding. The mean age is 52.5 years. Oesophageal varices were eradicated in 83.3% of cases after an average of 3.5 sessions. Recurrence of oesophageal varices after eradication was observed in 22% after an average follow-up of 7 months. 10 patients died before eradication of oesophageal varices from causes unrelated to the technique. The endoscopic variceal ligation is effective for eradication of oesophageal varices, with a low morbidity. This technique appears to be a method of choice in the prophylaxis of rebleeding from oesophageal varices.  相似文献   
348.
Subclavian vein cannulation was suggested as a temporary vascular access for hemodialysis since one of its advantages was considered to be no damage to blood vessels. As we observed six patients with symptomatic subclavian vein thrombosis among 148 patients having received subclavian vein cannulation for hemodialysis, we systematically performed subclavian venogram in 42 asymptomatic patients selected on the basis of a history of previous subclavian vein cannulation. Venograms were performed 15.7 +/- 8.9 months after the removal of the last catheter. Eight patients (19%) had complete thrombosis or severe stenosis of the subclavian vein while six patients (14%) had minimal luminal defects. Considering together the 48 patients, the group with thrombosis or severe stenosis (group 1, n = 14) was compared with the group with minimal defects or normal venograms (group 2, n = 34). In group 1, as compared with group 2, there were more female (64% vs 32%, p = 0.02), more cannulations per vein (1.87 +/- 0.35 vs 1.32 +/- 0.08, p less than 0.05) and more cumulative days of cannulation per vein (35.1 +/- 7.9 vs 24.4 +/- 1.1, p less than 0.001). No difference between the two groups was seen for the number of catheter infections, the number of catheters with poor flow or obstruction, the coagulation screening of the patients or the time-length between the removal of the last catheter and the venogram study. Two of the initially asymptomatic patients developed later on clinical problems related to the subclavian vein thrombosis. We conclude that the subclavian vein cannulation leads to significant damages of the vessels, excluding a whole arm, for future vascular access in some patients.  相似文献   
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Recent evidence points to progressive structural change in the airway wall, driven by chronic local inflammation, as a fundamental component for development of irreversible airway hyperresponsiveness. Acute and chronic inflammation is orchestrated by cytokines from recruited inflammatory cells, airway myofibroblasts and myocytes. Airway myocytes exhibit functional plasticity in their capacity for contraction, proliferation, and synthesis of matrix protein and cytokines. This confers a principal role in driving different components of the airway remodeling process, and mediating constrictor hyperresponsiveness. Functional plasticity of airway smooth muscle (ASM) is regulated by an array of environmental cues, including cytokines, which mediate their effects through receptors and a number of intracellular signaling pathways. Despite numerous studies of the cellular effects of cytokines on cultured airway myocytes, few have identified how intracellular signaling pathways modulate or induce these cellular responses. This review summarizes current understanding of these concepts and presents a model for the effects of inflammatory mediators on functional plasticity of ASM in asthma.  相似文献   
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