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51.
The gene encoding the beta-myosin heavy chain is one of the most frequently implicated in familial hypertrophic cardiomyopathy. Several mutations have been identified and some genotype-phenotype relationships have been assumed, particularly with regard to prognosis. Nevertheless, phenotypic expression is variable even in affected members of the same family carrying the same mutation. We identified the Ile263Thr mutation in several members of two unrelated Portuguese families. Penetrance, clinical behavior and prognosis were quite different between the two families, particularly concerning the occurrence of sudden death. Additional factors probably exist which account for the differences found. The complexity of hypertrophic cardiomyopathy makes it difficult to accurately determine genotype-phenotype relationships, and the screening and comparison of large affected families carrying the same mutation is warranted.  相似文献   
52.
The viability of the currently unculturable fungal pathogen Lacazia loboi can be determined by means of fluorescein diacetate-ethidium bromide (FD-EB) staining. This technique can be used in experimental study of the mycosis, in attempts to cultivate the fungus and in attempts to gauge the success of therapies. In the present study, the potential applications of FD-EB vital staining were studied using a proposed murine experimental model of lobomycosis. BALB/c mice were inoculated in the footpads with an L. loboi suspension that appeared in FD-EB staining to have lost viability after being held for 15 days at room temperature, whereas a control group of mice was inoculated with apparently viable fungi. The animals were killed after 1, 2, 4, 6, 8, 11 and 13 months. Both inoculated footpads were excised, one for determination of viability and the other for histological examination. In the group injected with nonviable material, no active infection was noted; inoculation sites showed small quantities of macrophage-laden infiltrate and no viable fungal cells. In the control group, the infection progressed with exuberant infiltrates surrounding copious fungal growth, most of which consisted of cells staining as viable in FD-EB. These results suggest that the FD-EB vital staining is a sensitive and specific method that can reliably be used for viability determination in L. loboi.  相似文献   
53.
Background: The long-term effect of recombinant human erythropoietin (rhEPO) on the blood-lipid profile has not been well documented. The aim of this study was to evaluate whether rhEPO therapy affects the lipid pattern. Methods: A group of 102 maintenance haemodialysis patients were treated for 2 years with rhEPO given intravenously at the end of the dialysis session. Attempts were made to keep the haemoglobin (Hb) at 10-11 g/dl and/or the haematocrit (Hct) at 30-35%. Twenty maintenance haemodialysis patients not treated with rhEPO were examined as controls. Total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, apolipoproteins A1 and B, and lipoprotein (a) [Lp (a)] were assessed at baseline (without rhEPO), and 1 and 2 years after the beginning of treatment. Hb, Hct and ferritin were measured monthly, and Kt/v was evaluated monthly and kept above 1.1. Results: During follow-up, in both groups, there was a significant increase in Apo A1 and no significant changes in the other lipid parameters. In the treated group, Hb and Hct increased significantly after the fourth month of treatment. Conclusions: Erythropoietin therapy does not affect significantly the levels of total cholesterol, LDL- and HDL-cholesterol, triglycerides, Apo B and Lp (a) in maintenance hemodialysis patients.  相似文献   
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55.
Echocardiographic assessment of left ventricular volume load   总被引:1,自引:0,他引:1  
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56.
Echocardiography (Echo) is the best non-invasive technique to study aortic regurgitation (AR). The authors (AA) start reviewing the place of M-Mode (MM) and two-dimensional (2D) Echo on the identification of AR and its cause, as well as on the assessment of left ventricular function. Secondly, the AA study the role of Doppler (Dp) techniques--pulsed (PDp), continuous (CDp) and colour coded (CCDp)--analysing their relative advantages and complementarity. They conclude that AR is best identified by PDp and MM Echo, its cause may be recognized by MM and 2D Echo, and its importance is correctly judged by CDp and CCDp Echo. Left ventricular function is best appreciated by 2D Echo, helped by CDp and CCDp Echo. The AA also state that, in AR, an haemodynamic study is injustifiable, unless Echo is technically incomplete, there is pluri-valvular disease insufficiently clarified, or coronarography is necessary.  相似文献   
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58.
Visceral leishmaniasis (VL) or kala-azar continues to persist as one of the major public health problems in many tropical countries. However, no effective treatment for radical cure of the disease is yet available. Miltefosine, an alkyl phospholipid compound, is the first orally effective drug, which has shown 98% cure rate of VL patients during phase III clinical trial in India. Since this drug requires long course of treatment and has long half-life, there are fairly good chances of emergence of resistance. Furthermore, this drug has produced severe side-effects in some of the cases.We therefore examined the possibility of minimizing these effects by applying miltefosine in lower doses in combination with picrloviv, an immunomodulator against Leishmania donovani in hamsters (Mesocricetus auratus). The picroliv per se showed no antileishmanaial potential. However, when given with suboptimal dose of miltefosine, it enhanced efficacy of the latter from 45 to 86% on day 7 post treatment and from 32 to 64% on day 28 post treatment. Interestingly, the efficacy of this combination was as good as the curative dose of miltefosine alone. Thus, this combination appears to offer a fruitful strategy for treatment of VL.  相似文献   
59.
Surface glycoconjugates play important roles in the infectious cycle of Leishmania major, including the abundant lipophosphoglycan (LPG) implicated in parasite survival in the sand fly vector and the initial stages of establishment in the mammalian host macrophage. We describe a system for inducible expression of LPG, applying a novel protein-based system that allows controlled degradation of a key LPG biosynthetic enzyme, UDP-galactopyranose mutase (UGM). This methodology relies on a mutated FK506-binding protein (FKBP) destabilizing domain (dd) fused to the protein of interest; in the absence of rapamycin analogs, such as Shld1, the dd domain is destabilized, leading to proteasomal degradation, whereas drug treatment confers stabilization. Tests in L. major using dd fusions to a panel of reporters and cellular proteins confirmed its functionality, with a high degree of regulation and low background, and we established the kinetics of protein activation and/or loss. Two inexpensive and widely available ligands, FK506 and rapamycin, functioned similarly to Shld1, without effect on Leishmania growth or differentiation. We generated parasites lacking UGM through deletion of the GLF gene and substitution with a ddGLF fusion construct, either as chromosomal knockins or through episomal complementation; these showed little or no LPG expression in the absence of inducer, whereas in its presence, high levels of LPG were attained rapidly. Complement lysis tests confirmed the correct integrity of the Leishmania LPG coat. These data suggest that the dd approach has great promise in the study of LPG and other pathways relevant to parasite survival and virulence.  相似文献   
60.
Riata and Riata ST silicone defibrillation leads are prone to externalization of conductors due to inside-out abrasion in the high-voltage system, causing structural damage which may be accompanied by electrical failure. These situations are easily detected by fluoroscopy or radiology and by inspection of intracardiac electrograms and/or measurement of impedance. However, older pulse generators do not automatically perform all the measurements needed to assess the integrity of the high-voltage electrical system, nor do they have patient notifier alerts in case of dysfunction.The authors describe the case of a patient in whom structural damage was detected on fluoroscopy during pulse generator replacement. They discuss the best strategy in these patients, considering current knowledge of this dysfunction.  相似文献   
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