Determination of oxygen tension in the subcutaneous tissue of cosmonauts during the Salyut-6 mission

A polarographic technique was used to measure the oxygen tension in subcutaneous tissue of the forearm of a cosmonaut prior to, after, and on the fourth day of a space mission performed by Salut-6. A drop in the oxygen exchange rate in the peripheral tissues during weightlessness was observed. The mechanisms of this change are studied, taking into consideration the blood distribution in the organism and microcirculation disorders reflected by a decreased blood flow rate in arterial-venous junctions

Investigation of cooling properties of the gaseous medium of a space station

An investigation of cooling properties of the gaseous medium was performed in the biosatellite Kosmos-936 as well as in the orbital complexes Soyuz-28/Salyut-6 and Soyuz-30/Salyut-6 with the aid of an especially constructed electric dynamic catathermometer. In this instrument current was measured which was necessary to keep a steady settled temperature of the sensing device. The investigation was performed because of the disturbed heat exhange of the human body caused by lack of natural convection in weightlessness. The instrument also enabled objective estimation of the temperature of the cosmonaut's ody in six optionally selected regions. The results obtained by means of the catathermometer will also enable defining the appropriate hygienic conditions of the gaseous medium of space stations

Monocyte derived dendritic cell responses in common variable immunodeficiency

The phenotype and function of monocyte derived dendritic cells (MdDC) were investigated in 25 patients with common variable immunodeficiency (CVID) to test for abnormalities that might help explain the failure of antibody production. Using MHC class II DR and CD86 as markers of maturation, DCs from the majority of CVID patients were normal. However 5 patients, the majority of whom had affected family members who had previously been shown to have a susceptibility genetic locus in the MHC region, expressed abnormally low levels of DR on repeated testing, in some cases associated with a reduced capacity to support antigen stimulated T cell proliferation; nevertheless costimulatory molecules for production of IL-13, IL-10 and IFN-γ from T cells were intact. In contrast to DCs from healthy donors, DCs from many CVID patients had high spontaneous production of IL-8 and lipopolysaccharide stimulation often caused a reduction in DR expression. Expression of other cytokines (IL-1a, IL-6 and IL-12), either before or after LPS stimulation, was normal. The data suggests there is a fundamental defect in the maturation of MdDCs in a subset of CVID patients that may compromise antigen presentation and subsequent antibody production

Deficiency in circulating natural killer (NK) cell subsets in common variable immunodeficiency and X-linked agammaglobulinaemia

Absolute and relative NK cell numbers were determined in peripheral whole blood by flow cytometry in patients with common variable immunodeficiency (CVID) (n = 55) and X-linked agammaglobulinaemia (XLA) (n = 19) on regular immunoglobulin (IVIG) therapy. Absolute CD3−CD16+ NK cell numbers were significantly reduced in CVID patients (median 108/μl, range 23–815), compared with normal subjects (n = 60) (289/μl, range 56–640, P < 0·001). Total lymphocyte concentrations were significantly lower in CVID (median 1587/μl, range 523–7519) compared with normal subjects (median 2019/μl, range 1124–3149, P = 0·004), with the percentage of NK cells also being significantly decreased (median 7·5%, range 3·0–33·0%, compared with 14·2%, range 2·6–30·8%, P < 0·001). In XLA, absolute NK cell numbers (median 140/μl, range 32–551, P < 0·001) but not relative numbers were significantly reduced compared with normal controls. We excluded the possibility that IVIG interferes with in vitro binding of CD16 MoAbs. Further analysis of NK cell subsets showed a deficiency of both CD16+ and CD56+ cells in CVID, most marked in the CD3−CD8dim subpopulation, which may be due to increased homing of these cells to the gut. Serial studies on a small number of patients suggest that IVIG therapy has no short-term effect on NK cells, although we cannot exclude an effect with prolonged use. Although there are no obvious clinical effects of the NK depletion in CVID and XLA, this may be a factor in their predisposition to cancer

Neurologic Complications of Common Variable Immunodeficiency

Common variable immunodeficiency is a rare disorder of immunity associated with a myriad of clinical manifestations including recurrent infections, autoimmunity, and malignancy. Though rare, neurologic complications have been described in a small number of case reports and case series of CVID patients. In this article, we present a patient with CVID who suffered significant neurologic morbidity and categorize the reported range of neurologic complications associated with CVID. Our case highlights the complex nature of neurologic manifestations in CVID patients, and our review of the current database suggests that infection and inflammatory neurologic disorders are the cause of most neurologic presentations