The characteristics of suppurative meningitis morbidity caused by Streptococcus pneumoniae and Haemophilus influenza type B

Of the 1,018 patients with purulent bacterial meningitis, hospitalized at the 2nd Clinical Infectious Hospital in Moscow during the period of 1980-1987, the diagnosis was confirmed in 54.7%; of these, meningitis of pneumococcal etiology was established in 44.8% and meningitis caused by H. influenzae, type b, in 23.8% of the patients. In meningitis of pneumococcal etiology high risk groups included mainly adults, especially those over 50 years, and children under 3 years of age. In meningitis of H. influenzae etiology high risk groups included mainly young children under 2 years of age. Meningitis of pneumococcal etiology was characterized by considerable death rate (on the average, 20%), while in meningitis of H. influenzae etiology death rate was 3 times lower. Pneumococci of serotypes 1, 3, 6, and 19 were found to be of the highest etiological importance for adults and pneumococci of serotypes 19, 6, 12, and 1, for children. In recent years greater etiological role of serotype 42 in adults was noted. The study of the spread of meningitides of different etiology is a high-priority task for this country.     

HIV Controller CD4+ T Cells Respond to Minimal Amounts of Gag Antigen Due to High TCR Avidity

HIV controllers are rare individuals who spontaneously control HIV replication in the absence of antiretroviral treatment. Emerging evidence indicates that HIV control is mediated through very active cellular immune responses, though how such responses can persist over time without immune exhaustion is not yet understood. To investigate the nature of memory CD4+ T cells responsible for long-term anti-HIV responses, we characterized the growth kinetics, Vβ repertoire, and avidity for antigen of patient-derived primary CD4+ T cell lines. Specific cell lines were obtained at a high rate for both HIV controllers (16/17) and efficiently treated patients (19/20) in response to the immunodominant Gag293 peptide. However, lines from controllers showed faster growth kinetics than those of treated patients. After normalizing for growth rates, IFN-γ responses directed against the immunodominant Gag293 peptide showed higher functional avidity in HIV controllers, indicating differentiation into highly efficient effector cells. In contrast, responses to Gag161, Gag263, or CMV peptides did not differ between groups. Gag293-specific CD4+ T cells were characterized by a diverse Vβ repertoire, suggesting that multiple clones contributed to the high avidity CD4+ T cell population in controllers. The high functional avidity of the Gag293-specific response could be explained by a high avidity interaction between the TCR and the peptide-MHC complex, as demonstrated by MHC class II tetramer binding. Thus, HIV controllers harbor a pool of memory CD4+ T cells with the intrinsic ability to recognize minimal amounts of Gag antigen, which may explain how they maintain an active antiviral response in the face of very low viremia.     

Biology,abundance, and life cycle of big-head Far East goby <Emphasis Type="Italic">Gymnogobius urotaenia</Emphasis> (Gobiidae) from the Serebryanka River (Central Primor’e)

Biology and seasonal (from May to November) population dynamics of big-head Far East goby Gymnogobius urotaenia from the Kolkhoznaya channel is analyzed (the estuary part of the Serebryanka River). This species attains length 145 mm, weight 23.9 g, and age 5+. Males live one year longer than females. In both sexes, the highest growth rate is observed in the first and second years of life, and that of weight growth is observed in the third and fourth years. It spawns from the end of May until the end of June. The absolute fecundity does not exceed 4000 eggs. The base of the diet consists of mysids. This is an abundant species. The annual life cycle of G. urotaenia comprises spawning migration, spawning, embryonic development, pelagic larval stage, the phase of transition to bottom mode of life, feeding, and wintering migration.     

ABCA1 gene expression in peripheral blood lymphocytes and macrophages in patients with atherosclerosis

ABCA1 transporter is known to play important role in the cholesterol transport from peripheral tissues. However its contribution in atherosclerosis development remains not completely understood. Using Real Time PCR, a significant reduction of ABCA1 mRNA level in leukocytes of patients with atherosclerosis was determined when compared with controls. Mean ABCA1 expression levels in leukocytes for the group of patients and for the control group are 0.57 +/- 0.28 and 0.93 +/- 0.14 (p = 0.02). At the same time we detected a significant increase of ABCA1 mRNA level in macrophages of patients when compared with controls. Mean ABCA1 expression levels in macrophages for the group of patients and for the control group are 1.32 +/- 0.10 and 0.90 +/- 0.14 (p = 0.014). In summary, we suggest that expression level of ABCA1 gene may contribute to the development of atherosclerosis.     

The expression of ABCG1 transporter gene in peripheral blood mononuclear cells of patients with atherosclerosis

The antiatherogenic role of high-density lipoproteins (HDL) was demonstrated by numerous experimental, clinical and epidemiological studies. The mechanism underlying the antiatherogenic potential of HDL is based on their involvement in reverse cholesterol transport (RCT) from peripheral tissues into the liver. Transmembrane transporter ABCG1 is a key RCT protein. Its function is to remove cholesterol from cells and transfer it to HDL. The role of ABCG1 transporter in the development of atherosclerosis in humans remains unexplored. The goal of our study was to investigate the expression of ABCG1 gene in patients with atherosclerosis. Real-time PCR was applied to study ABCG1 mRNA content in leukocytes, monocytes, and macrophages activated with macrophage colony-stimulating factor (M-CSF) from patients with atherosclerosis and healthy people. The amount of ABCG1 protein in monocytes and macrophages of patients and healthy donors was assayed by immunoblotting. It was found that the level of ABCG1 mRNA (p < 0.001) and ABCG1 protein (p < 0.05) was lower in macrophages of patients with atherosclerosis. The level of ABCG1 mRNA in monocytes of patients with artery occlusion was lower than in patients with features of lesser stenosis and the control group (p < 0.05). No correlation was found between ABCG1 gene expression and total and HDL cholesterol levels in the blood plasma. It can be concluded that reduced ABCG1 gene expression in monocytes and macrophages may be critical for the atherosclerosis progression.     

CD4 dynamics over a 15 year-period among HIV controllers enrolled in the ANRS French observatory

Background

There are few large published studies of HIV controllers with long-term undetectable viral load (VL). We describe the characteristics and outcomes of 81 French HIV controllers.

Methods and Results

HIV controllers were defined as asymptomatic, antiretroviral-naïve persons infected ≥10 years previously, with HIV-RNA <400 copies/mL in >90% of plasma samples. All available CD4 and VL values were collected at enrolment. Mixed-effect linear models were used to analyze CD4 cell count slopes since diagnosis. HIV controllers represented 0.31% of all patients managed in French hospitals. Patients infected through intravenous drug use were overrepresented (31%) and homosexual men were underrepresented (26% of men) relative to the ANRS SEROCO cohort of subjects diagnosed during the same period. HIV controllers whose VL values were always below the detection limit of the assays were compared with those who had rare “blips” (<50% of VL values above the detection limit) or frequent blips (>50% of VL values above the detection limit). Estimated CD4 cell counts at HIV diagnosis were similar in the three groups. CD4 cell counts remained stable after HIV diagnosis in the “no blip” group, while they fell significantly in the two other groups (−0.26√CD4 and −0.28√CD4/mm³/year in the rare and frequent blip groups, respectively). No clinical, immunological or virological progression was observed in the no blip group, while 3 immunological and/or virological events and 4 cancers were observed in the blip subgroups.

Conclusions

Viral blips in HIV controllers are associated with a significant decline in CD4 T cells and may be associated with an increased risk of pathological events, possibly owing to chronic inflammation/immune activation.