Bee venom inhibits superoxide production by human neutrophils.

Investigation of the antiinflammatory properties of bee venom demonstrates that it inhibits production of superoxide anion by human neutrophils in a potent, selective, nontoxic, dose-dependent fashion, both pre- and poststimulation by particulate and soluble activators of the neutrophil oxidative metabolism burst. The effect is not due to receptor competition, superoxide dismutase, and/or catalase activity, scavenging, or indicator media effects. These findings may explain the antiinflammatory effects of whole bee venom in experimental systems, its widespread use in folk medicine, and lead to the development of potent, new antiinflammatory substances for therapeutic use in man.

Bee venom melittin blocks neutrophil O2- production.

Bee venom (BV) is used in folk medicine to treat arthritis. It has antiinflammatory effects in animal models of rheumatic disease. We have studied the effects of BV on human neutrophil production of superoxide (O2-) and hydrogen peroxide, finding potent, nontoxic, dose-dependent production inhibition. Melittin, the major fraction of BV (50-70%) shows high-affinity calmodulin binding (Kd 3 nM). Drugs which bind calmodulin, such as trifluoperazine, inhibit O2- production by human neutrophils. For these reasons we have investigated the effect of melittin and other BV peptides on O2- production by human peripheral blood leukocytes. We show that melittin inhibited O2- production both pre- and poststimulation in contrast to other BV fractions which were without effect. Oxygen radicals and their derivatives from inflammatory cells are implicated in the tissue damage occurring during inflammation. The inhibition is due to a direct effect on cells, and not indicator medium, dismutation, toxic or scavenging effects. We propose that melittin may serve as a prototype small (mol wt 1280), cationic, amphipathic, calmodulin-binding, membrane-active, superoxide-production-inhibiting peptide, providing a model for peptides which could have a role in in vivo regulation of radical production.

The tiron radical as indicator substance in catalytic determination of trace metals.

The tiron-hydrogen peroxide reaction used for catalytic determination of trace metals is studied with respect to the indicator substance-the oxidation product of tiron absorbing at 44Onm. Contrary to assumptions in the literature, it is shown by electrochemical techniqus EPR spectroscopy and visible spectrophotometry that the indicator substance is not the o-quinone derivative of tiron (lambda(max) = 372 nm) but the tiron semiquinone radical with a g-value of g(o) = 2.0049 and molar absorptivity = (3.5 +/- 0.5) x 10(3) 1.mole(-1).cm(-1) at 440 nm.

Dechlorination of polychlorinated biphenyls, dibenzo-p-dioxins and dibenzofurans on fly ash.

Dechlorination of commercial mixtures of polychlorinated biphenyls (PCB) as well as polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) on extracted and non-extracted fly ash obtained from municipal waste incinerator (MWI) was studied in closed systems under nitrogen atmosphere at temperatures of 260 degrees C and 340 degrees C. Decomposition results (given as the difference between PCB or PCDD/F molar amounts before and after the experiment (in %) due predominantly to dechlorination reactions) and detoxification data (expressed similarly but related to toxic PCB and PCDD/F congeners only and given in I-TEQ units) are reported. Detoxification of Delor 105/80T at 260 degrees C and 340 degrees C at a loading of 0.65 wt%, was 99.48% and 100%, respectively. The decomposition of Delor 103 at 340 degrees C and for the loading of 0.75 wt%, corresponded to 99.99%. The detoxification capability of PCDD/Fs on extracted and non-extracted fly ash for loading of 130 and 264 ng/0.4 g of fly ash at 340 degrees C made 96 and 98%, respectively.

Biota participating in wastewater treatment in a horizontal flow constructed wetland.

During the period 1996-1997, three constructed wetlands with sub-surface horizontal flow were investigated. All systems are designed to treat municipal sewage from small villages (150, 200 and 300 PE). The survey included microscopical identification of organisms in both wastewater and filtration substrate. The organisms were used as an indication of oxygen conditions (aerobic, anoxic and anaerobic) in the particular microenvironment. Saprobiological terms characterizing different levels of saprobity were employed to characterize inflowing wastewater, filtration bed and outflowing water. The occurrence of organisms was correlated with BOD5 values in particular profiles. It has been found that the biocenosis in the inflowing wastewater differs from those found in the filtration bed and water outflowing from the vegetated beds. The organisms were grouped into those living under anaerobic and anoxic conditions and those living under aerobic conditions. More than 70 species of bacteria, amoebae, ciliates, rotifers, colorless flagellates, cyanobacteria and algae were found and the most important 45 species were figured in a plate together with saprobiological information for each species. Biota of the inflowing water is usually restricted to bacteria, ciliata and colorless flagellata while the organisms found in outflowing water as well as in periphyton growing on outflow structures indicate 2-3 levels better quality.

[Weil's disease: a severe case with respiratory insufficiency]. / Weilova nemoc: tezký prubeh s respiracní insuficiencí.

In the patient case (man, age 25) with suspected leptospirosis, indication for polymerase chain reaction (PCR) are supposed and procedures suitable for taking biological material are recommended. In the presented case of leptospirosis, serious conditions were accompanied by high fever, chills, hepatorenal failure, meningitis, pneumonia, increased bleeding time and further symptoms are described. Introduction of the molecular biological methods (PCR) enables to determine leptospiroses diagnosis even in the early phase of the disease, when the antibodies are not yet formed. Detection of DNA pathogenic leptospires in the PCR method is completed with serological examination by microagglutination-lysis (MAL) method for determination of the corresponding serovar that is important from therapeutic and epidemiological reasons.

Managing death. Room to mourn.

More than a quarter of deaths occurred on wards which offered relatives and staff no privacy. In a fifth of cases no information was available on how to register a death. Almost half of the staff had received no training in bereavement. More than half of the staff wanted training or further training.

Vaccines against mycobacteria and other intracellular multiplying bacteria.

As the prototype of a vaccine against mycobacterial infection, the BCG (bacille bilié Calmette et Guérin) has been used against tuberculosis for more than 60 years. It is the only live attenuated vaccine used on humans in more than 182 countries or territories in the world, and very few changes have been made in its fabrication and distribution, except for the production of lyophilized seed-lots. However, its history is marked with controversies concerning its innocuity and efficacy. While BCG safety is no longer a matter of debate, the question of its effectiveness is still pertinent, and results in several controlled trials have shown great variability (from 0 to 80%). The studies of different variables involved in such results have shown statistical bias, and numerous factors are involved in the highly complex interrelationships between the host, the pathogen and environmental factors. World-wide research is now being conducted under the auspices of the World Health Organisation, in order to gain further knowledge of the immunology of tuberculosis and leprosy. Such results are aimed at understanding variations in BCG efficacy and producing strategies for developing new vaccines and alternative methods for prophylaxis and diagnosis. Concerning human infections due to other facultative intracellular multiplying bacteria, there are relatively few vaccines which are able to give long-lasting and efficient protection. Some controversy remains as to the live attenuated mutant GalE S. typhi Ty21a, and there is hope for the new insoluble phenol extract from Brucella abortis, strain B19. Further research is necessary on the others, for instance, Listeria monocytogenes, Chlamydia trachomatis and Legionella sp.

[Use of purified antigens in the serodiagnosis and epidemiologic studies of human malaria. Importance of the ELISA technic for determining specific IgG and IgM]. / Utilisation d'antigènes purifiés pour le sérodiagnostic et les études épidémilogiques du paludisme humain. Intérêt de la technique ELISA pour la mise en évidence des IgG et des IgM spécifiques.

A purified antigen was isolated from the red blood cells of Saimiri sciureus which was experimentally infected by Plasmodium falciparum. An enzyme immunoassay (ELISA) was carried out thanks to this antigen. The results obtained with the test were evaluated from two series of sera: one coming from an endemic area, the other taken out of it. The results were compared with those obtained with indirect fluorescent antibody test (IFAT) which is considerated as reference test. There is a good correlation between the two tests when anti-IgG conjugate is used for ELISA but there is no correlation with anti-IgM conjugate. One of the advantages of the ELISA, is that it allows a separate evaluation of specific IgG and IgM. Consequently distinction between recent and past infection would be possible. This may be useful for estimating the efficiency of an antimalaric campaign.

Phenotypic expression of genetically-controlled natural resistance to Mycobacterium bovis (BCG).

Mycobacterium bovis (BCG), when maintained in vitro, readily incorporates [3H]uracil, the RNA precursor. The rate of [3H]uracil incorporation into bacilli is sharply reduced when the BCG is phagocytized by murine adherent resident peritoneal macrophages and subsequently released by the lysis of monolayers. Macrophages derived from mouse strains that are innately resistant to BCG infection in vivo (Bcgr) are able to inhibit the [3H]uracil incorporation into the bacilli in a significantly more effective way than macrophages from BCG-susceptible (Bcgs) strains. This difference is best demonstrated with a low rate of infection (BCG: macrophage ratio between 1:1 and 2:1), and is most pronounced at 4 to 5 days after in vitro infection of macrophage monolayers. In vivo interaction of BCG with peritoneal macrophages in situ results in the same pattern of enhanced inhibition of [3H]uracil incorporation by Bcgr macrophages. The use of Bcg-congenic mouse strains has confirmed that the Chromosome 1 Bcg (Ity, Lsh) locus is regulating the antimycobacterial activity of macrophages. We conclude that the resident macrophage is the cell population that expresses the phenotype of genetically determined resistance to BCG infection.

Preliminary evidence of natural resistance to Mycobacterium bovis (BCG) in lepromatous leprosy.

An assay system has been developed based on radiometric quantification of 3H uracil incorporation into viable BCG in the absence or presence of blood monocytes in cultures from untreated lepromatous (LL) or tuberculoid (TT) leprosy patients. 3H Uracil incorporation into BCG was inhibited when the bacilli were cultivated in the presence of blood-derived macrophages in culture for four days, and that inhibition was always greater with macrophages harvested from LL patients compared to TT patients. The reasons for such an observed difference in humans are discussed according to our knowledge obtained in murine models of mycobacterial infections.

[Increase in dismutase activity in splenic leukocytes of mice sensitive to BCG and Mycobacterium lepraemurium]. / Augmentation de l'activité dismutasique dans les leucocytes spléniques de souris sensibles au BCG et à Mycobacterium lepraemurium.

A marked enhancement of superoxide dismutase activity was evidenced when Mice receptive to BCG and Mycobacterium lepraemurium were infected. Such increase was not found in non receptive Mice. This seems related to a genetic factor of the breed of Mice studied.

[Leprosy tests: diagnostic problems (apropos of 2 cases)]. / Les réactions lépreses: problèmes de diagnostic (à propos de deux observations).

Two cases of reactional leprosy leading to wrong diagnosis are reported. The first one concerns a reversal reaction predominantly neuritic, initially taken for polyarthritis. The second one concerns an erythema nodosum leprosum with extensive cutaneous necrosis (Lucio's phenomenon or ulcerative lazarine leprosy). Main aspects and mechanisms of leprosy reactional states are reviewed. It is emphasized that errors or delays in diagnosis are often caused by failing to recognize cutaneous or neuritic symptoms.