The immunological and virological response in human immunodeficiency virus type-1 (HIV-1) infected Indian individuals on HAART therapy: a one-year follow up study

Currently, antiretroviral therapy has become more affordable even in developing countries and it is being used in India. Fifteen HIV-1 infected individuals, who were on highly active antiretroviral therapy (HAART), were followed up for an average period of one year. The plasma viral load and CD4+ T cell estimation done at mean intervals of 5 months and 11 months after initiation of therapy showed a good response to therapy in 14 (93%) individuals.     

Evidence for selection of insecticide resistance due to insensitive acetylcholinesterase by carbamate-treated nets in Anopheles gambiae s.s. (Diptera: Culicidae) from Côte d'Ivoire

Pyrethroid-treated nets are an efficient tool for reducing malaria transmission and morbidity. The recent evolution of pyrethroid resistance in several Anopheles species represents a major threat for the future success of roll back malaria in Africa. The possible use of nonpyrethroid insecticides, such as carbamates, on nets is a promising alternative solution because these insecticides are effective against susceptible and pyrethroid-resistant populations of Anopheles and Culex mosquitoes. Unfortunately, carbamate resistance as a result of insensitive acetylcholinesterase has recently been detected in Anopheles gambiae s.s. populations from C?te d'Ivoire. Using biochemical assays on surviving Anopheles mosquitoes from an experimental hut trial, we showed evidence for selection for an insensitive acetylcholinesterase mechanism by carbamate impregnated bednets. However, no such selection has been found with nets treated with pyrethroid alone or pyrethroid/carbamate "two-in-one" -treated nets. Because pyrethroid-impregnated nets were suspected to select for the Kdr mutation in An. gambiae, we propose that use of two-in-one nets could be a promising alternative strategy for the management of insecticide resistance in malaria vectors.     

Prevalences of herpesviruses DNA sequences in salivary gland biopsies from primary and secondary Sj?gren's syndrome using degenerated consensus PCR primers.

BACKGROUND: Sj?gren's syndrome (SS) is an autoimmune exocrinopathy associated with multiple autoantibodies, lymphocyte infiltration of various organs, and functional deficiency of T cells. Several viruses have been implicated by PCR based studies, but their contribution to the pathophysiology of SS is still controversial. OBJECTIVES: In an attempt to explore the presence of human herpesviruses DNA sequences in salivary glands biopsies from patients suffering of SS, a recently developed strategy based on PCR with consensus degenerated primers that allowed to detect known and eventually unknown herpesviruses was used. STUDY DESIGN: Salivary glands biopsies from 55 patients suffering of primary and SS syndrome were explored by herpesviruses consensus PCR primers and all the PCR products were sequenced. RESULTS: Nine out of 55 salivary glands were positive by PCR and sequence analyses allowed to identify Epstein-Barr virus (EBV) in 6 cases and herpes simplex virus (HSV)-1 in 3 cases. We did not detect any sequences that could be related to a new herpesvirus. CONCLUSION: In view of the good sensitivity of the technique used, our study is not consistent with SS being associated with an unknown herpesvirus. However, our results suggest that EBV and HSV-1 could be implicated in a subset of SS cases and this possibility needs to be explored, to assess the potential benefit of antiviral drugs in some cases.     

Identification and characterization of a Streptococcus pyogenes operon involved in binding of hemoproteins and acquisition of iron

The hemolytic Streptococcus pyogenes can use a variety of heme compounds as an iron source. In this study, we investigate hemoprotein utilization by S. pyogenes. We demonstrate that surface proteins contribute to the binding of hemoproteins to S. pyogenes. We identify an ABC transporter from the iron complex family named sia for streptococcal iron acquisition, which consists of a lipoprotein (siaA), membrane permease (siaB), and ATPase (siaC). The sia transporter is part of a highly conserved, iron regulated, 10-gene operon. SiaA, which was localized to the cell membrane, could specifically bind hemoglobin. The operon's first gene encodes a novel bacterial protein that bound hemoglobin, myoglobin, heme-albumin, and hemoglobin-haptoglobin (but not apo-haptoglobin) and therefore was named Shr, for streptococcal hemoprotein receptor. PhoZ fusion and Western blot analysis showed that Shr has a leader peptide and is found in both membrane-bound and soluble forms. An M1 SF370 strain with a polar mutation in shr was more resistant to streptonigrin and hydrogen peroxide, suggesting decreased iron uptake. The addition of hemoglobin to the culture medium increased cell resistance to hydrogen peroxide in SF370 but not in the mutant, implying the sia operon may be involved in hemoglobin-dependent resistance to oxidative stress. The shr mutant demonstrated reduced hemoglobin binding, though cell growth in iron-depleted medium supplemented with hemoglobin, whole blood, or ferric citrate was not affected, suggesting additional systems are involved in hemoglobin utilization. SiaA and Shr are the first hemoprotein receptors identified in S. pyogenes; their possible role in iron capture is discussed.     

Persistent expression of the alpha1S-dihydropyridine receptor in aged human skeletal muscle: implications for the excitation-contraction uncoupling hypothesis of sarcopenia

Previous studies on aged animal muscle suggest that excitation-contraction uncoupling and fibre transitions play a central role in sarcopenia, the progressive loss and functional decline of aging skeletal muscle fibres. A drastic reduction in the voltage-sensing alpha1S-subunit of the transverse-tubular dihydropyridine receptor is believed to be the underlying cause for a decreased transmission of the surface depolarization signal into Ca2+-mediated muscle contraction. Extending these studies to human muscle, we asked whether potential changes in the relative expression of the voltage sensor occur in senescent human fibres. For internal standardization and as markers of potential fast-to-slow transitions, the fast isoforms of the Ca2+-binding element calsequestrin and the myosin heavy chain were employed. Besides small inter-individual variations in expression levels, the microsomal immunoblot analysis of vastus lateralis autopsy specimens from male humans aged 18 to 82 years of age showed no major changes in the relative abundance of the alpha1S- and alpha2-dihydropyridine receptor, fast calsequestrin and the slow/fast myosin heavy chains. The oligomeric status of the alpha1S-dihydropyridine receptor was unaltered in aged fibres. Biochemical assays revealed no significant modifications in Ca2+-ATPase activity and a reduced Ca2+-binding capacity in aged human muscle preparations. Although impairments of other Ca2+-regulatory proteins and/or disturbed protein-protein interactions might be involved in the pathophysiological changes of sarcopenia, dihydropyridine receptor and calsequestrin expression seem to be preserved during the aging process of human skeletal muscle fibres. Hence, the supposition that excitation-contraction uncoupling is responsible for sarcopenia can not be transferred from animal models to senescent human muscle without modifications.     

试剂对脱钙骨基质成骨能力影响的实验研究

目的 :研究异体骨基质制备过程中常用的脱脂和脱钙试剂溶液对其成骨能力的影响。方法 :8周鼠龄的Wistar雌鼠作为供体 ,切取胫股骨 ,碾磨成 12 5～ 80 0微米的颗粒 ,分成四组 ,分别用丙酮 -盐酸、丙酮 -乙二胺四乙酸 (EDTA)、三氯甲烷 -甲醇 -EDTA或三氯甲烷 -甲醇 -盐酸 (控制组 )脱脂和脱钙。冷冻干燥处理后 ,每 3 0mg装入一胶囊中。 60只 6周鼠龄的Wistar雌鼠作为受体 ,植入腰背肌中 ,每只鼠接受同一组植入材料 2枚。术后 6周取标本测定重量、干燥后的重量、钙含量、碱性磷酸酶含量和组织形态学定量测定。结果 :丙酮 -盐酸组的干燥重量 (P <0 .0 1)和钙含量 (P <0 .0 5 )明显高于控制组。结论 :用丙酮清除脂质的异体骨基质成骨能力优于用三氯甲烷 -甲醇混合液。EDTA或盐酸脱钙对其成骨能力无明显影响。     

A biological window on psychological development

The articles in this special issue of Developmental Psychobiology were presented in May 2005 at an international institute on developmental science hosted by the University of North Carolina at Chapel Hill. Conducted annually at one of the participating universities, these meetings are intended to foster collaboration and build consensus on specific theoretical, methodological, and analytical issues faced by developmentally oriented researchers. The overall goal of the 2005 meeting, titled "Integrating Biology and Developmental Science," was to identify different ways by which a developmental study of psychological phenomena in their joint biological and behavioral aspects may shed new light on their organization in the individual. The six contributions to this special issue illustrate how a biological window on developmental processes can further this scientific endeavor.     

Lymph node pathology in pulmonary veno-occlusive disease and pulmonary capillary heamangiomatosis

To assess the histological bases of lymphadenomegaly, which has been reported as a frequent radiological finding in pulmonary veno-occlusive disease (PVOD), we have reviewed pulmonary and mediastinal lymph nodes resected during lung transplantations in 19 patients suffering from PVOD and related pulmonary capillary haemangiomatosis (PCH). Lymphatic congestion was common and was often obvious in subsegmental and segmental lymph nodes. Vascular transformation of the sinuses, intra-sinusal haemorrhage with erythrophagocytosis and lymphoid follicular hyperplasia were frequent especially in lobar, hilar and mediastinal lymph nodes. These lesions were very significantly less frequent in 33 cases of pulmonary hypertension unrelated to PVOD. Due to their thoracic location, these non-specific lesions could simulate other diagnoses such as Castleman disease or lymphangioleiomyomatosis. However, in the setting of pulmonary hypertension, they should suggest PVOD and PCH. They are probably secondary to venous congestion, veno-lymphatic shunts and angiogenetic factors associated with these diseases.