Eosinophil accumulation induced by human interleukin-8 in the guinea-pig in vivo

Interleukin-8 (IL-8) is a neutrophil chemoattractant cytokine. Initially IL-8 appeared to exhibit specificity for neutrophils over other cells of the immune system. However, several recent studies have shown that this mediator can also activate other leucocyte types in vitro. In this study we have used an in vivo model of local [111In]leucocyte accumulation in the guinea-pig and an in vitro assay of leucocyte activation (changes in cytosolic-free Ca2+) to investigate the eosinophil chemoattractant activity of IL-8. The intradermal injection of recombinant human (rh)IL-8 induced a dose-dependent accumulation of intravenously administered [111In]eosinophils into the skin sites over 4 hr. Time-course experiments revealed that this cell infiltration was delayed in onset, occurring between 1 and 2 hr after injection of IL-8. The delay may indicate that IL-8 operates via an indirect mechanism. In contrast, eosinophil accumulation induced by the complement fragment C5a occurred within the first hour following injection. Other human cytokines, IL-1, IL-3, IL-5, tumour necrosis factor (TNF) and granulocyte-macrophage colony-stimulating factor (GM-CSF), were not eosinophil chemoattractants in this in vivo test system. Direct activation of eosinophils by IL-8 was demonstrated in vitro by a transient elevation in cytoplasmic-free Ca2+ levels where it was less potent than either rhC5a or leukotriene B4 (LTB4). Experiments using [111In]neutrophils in vivo indicated that rhIL-8 and rhC5a were similar in potency in inducing local neutrophil infiltration into guinea-pig skin. The demonstration of the eosinophil chemoattractant activity of IL-8 in vivo raises the possibility that this cytokine, or a structurally related molecule, contributes towards eosinophil infiltration in a number of inflammatory conditions such as asthma, helminthic infections and adult respiratory distress syndrome.     

Antimicrobial and membranolytic activity of sterically hindered phenols

Antimicrobial activity of some complicated space phenols (screened) was studied. The compounds had different activities against grampositive bacteria and were inactive against gramnegative microbes. Di-tertiary butyl derivatives of pyrocatechol and resorcin showed the highest activities. The MICs of such derivatives for the collection strains of Bacillus megaterium, Bacillus subtilis and Staphylococcus aureus were 8 to 30 micrograms/ml and exceeded 6-25 times those of the nonsubstituted analogs. The derivatives of pyrocatechol and resorcin impaired the membrane permeability in susceptible intact cells of B.megaterium and S.aureus 209P and had no effect on the membrane permeability of the Escherichia coli resistant cells. In concentrations up to 200 micrograms/ml the nonsubstituted analogs of pyrocatechol and resorcin did not impair the membrane permeability in the intact cells of the above bacteria. Di-tertiary butyl derivatives of pyrocatechol and resorcin had lytic activity with respect to cytoplasmic membranes (protoplasts) of B.megaterium and had no lytic action on E.coli spheroplasts. The antimicrobial spectrum correlated with the membranotropic properties of the compounds. It was suggested that the target of the antimicrobial action of the screened phenols was the bacterial cell cytoplasmic membrane.     

Optical and Electrical Properties of Polycrystalline ZnSe:Li

ZnSe:Li ceramics were prepared by hot-pressing powder mixtures of ZnSe and LiOH at 1050°C under a pressure of 30 MPa. The luminescence spectra of the ceramics are dominated by a red emission centered at 630 nm. With increasing Li concentration, the intensity and width of the red band increase, and the band shifts to shorter wavelengths. The nature of the emission centers and the effect of the doping level on their parameters are discussed. The electrical properties of the ZnSe:Li ceramics can be understood in terms of percolation in heterogeneous systems.     

Outbreak of viral hepatitis B in a rural community in India linked to inadequately sterilized needles and syringes

BACKGROUND AND METHODS: Four hundred and eighty-four patients with inflammatory bowel disease underwent clinical examination, ultrasonography, and biochemical liver function tests, to estimate the prevalence of hepatobiliary alterations. The patient group included patients without a history of liver disease. Controls were recruited from patients with functional symptoms. RESULTS: More patients with ulcerative colitis than controls had liver steatosis and increased alkaline phosphatase levels. Factors increasing the probability of liver damage were long-standing disease, the presence of moderate/severe disease activity, and treatment with steroids and mesalazine. A significant association was found between biliary disease and long-standing colitis and also therapy with steroids and mesalazine. Alkaline phosphatase and aminotransferase levels were significantly higher in Crohn's disease patients than in controls. Hepatic and biliary damage was found more commonly in the 1st year after diagnosis. CONCLUSIONS: The monitoring of hepatobiliary function is suggested for patients with inflammatory bowel disease, even in the absence of symptoms and history.     

Erythrocyte structural changes as a possible reason for the low effectiveness of specific therapy for carbophos poisoning

By method of scanning electron microscopy erythrocyte structure was studied in rats in carbophos poisoning. Following up to 76% acetylcholinesterase inhibition with distinct symptoms of intoxication nearly 30% of erythrocytes were deformed and tended to aggregate. Observation of blood circulation in vessels of pia mater revealed formation of erythrocyte conglomerations in vascular bed. Erythrocytes get stuck in small vessels, disturbing blood microcirculation. Supposedly, obstruction of the smallest vessels with conglomerations is one of the reasons of exotoxic shock development and low efficiency of treatment of carbophos poisoning by means of specific antidotal cholinolytic drugs and cholinesterase reactivators.     

The emergence of form by replication

It is shown with a simple mathematical model that if a system exhibits a given form (a spatial structure) and is put in contact with another system of the same type but in a state of spatial disorder, then under certain conditions their mutual interaction as they evolve in time allows replication of form in the disordered system with a controllable degree of faithfulness.     

The standardization of medical care and the training of medical personnel

The medical specialist training at all levels (medical orderly, doctor's assistant, general practitioner, doctors) should be based on the medical care standards. Preliminary studies in the field of military medicine standards have demonstrated that the medical service of the Armed Forces of Russia needs medical resources' standards, structure and organization standards, technology standards. Military medical service resources' standards should reflect the requisitions for: all medical specialists' qualification, equipment and material for medical set-ups, field medical systems, drugs, etc. Standards for structures and organization should include requisitions for: command and control systems in military formations' and task forces' medical services and their information support; health-care and evacuation functions, sanitary control and anti-epidemic measures and personnel health protection. Technology standards development could improve and regulate the health care procedures in the process of evacuation. Standards' development will help to solve the problem of the data-base for the military medicine education system and medical research.     

Gas exchange and hemodynamics following complete replacement of blood with a solution of purified hemoglobin

Complete exchange blood substitution (down to hematocrit level of 1--3%) by 7--8% solution of hemoglobin (Hb) completely free of stromas and procoagulant activity of human hemoglobin was performed in cats. The Hb solution is capable of carrying oxygen and maintaining the life of the animal with a complete blood loss for some time. The Hb solution is readily saturated with oxygen in the lungs and releases oxygen in the tissues, although to a significantly lesser degree than Hb in the red cell; besides, the Hb solution maintains the basic value of hemodynamics for some time.