The effect of iuvemon on oogenesis in female Anopheles sacharovi Favre mosquitoes and their infection with the malarial causative agent Plasmodium gallinaceum Brumpt

The paper provides evidence that the An. sacharovi females which do not develop mature eggs after blood-sucking on the malaria-infected donor could not be infected by the bird malaria agent P. gallinaceum. The addition of juvemon (an analogue of juvenile hormone) to glucose solution (mosquito carbohydrate diet) before blood meal stimulates the vitellogenesis of the mosquito after blood digestion, as clearly demonstrated on the female with an incomplete portion of the infected blood. This study has demonstrated that the juvemon does not exert a direct effect on mosquito susceptibility to the bird malaria agent, but it increases the number of females with mature eggs, thus promoting the increase in the percentage of the infected specimens and the number of oocysts.     

Etiology, pathogenesis and treatment of severe recurrent forms of erysipelas of the lower extremities

The experience of treatment of 314 patients with erysipelas was summarized. The organizational principles of struggle against this disease are proposed.     

Distribution of CCR5-delta 32 gene deletion across the Russian part of Eurasia

We describe the cases of two premature infants carrying a central venous line who developed on the fourth day of life a catheter related intracardiac thrombus. Although they were clinically asymptomatic we opted for thrombolytic treatment considering the potential risks of this situation. Treatment with recombinant tissue plasminogen activator (rt-PA) was performed for one day in the first case and for three days in the second one, in association with fresh frozen plasma. Thrombus dissolution occurred in both patients and no adverse effects were noted. In our experience tissue plasminogen activator was a therapy acceptably safe and effective inducing clot lysis in very low birthweight neonates into critical situations.     

A mouse model for staphylococcal enterotoxins toxicity

The study of staphylococcal enterotoxins (SE), which can adversely affect man and animals, is hindered by the absence of a practical animal model. Only humans and primates are sensitive to SE oral intake whereas other species such as cats and dogs require intravenous SE administration to induce biological effects. Rodents are very resistant even to relatively high doses of SE. Treatment of mice with D-galactosamine (20 mg/mouse) rendered them highly susceptible to micrograms of toxins leading to lethal shock. Differences in toxic potential have been observed between types of SE. Carboximethylated SE, which have been shown not to induce emesis in primates were also able to induce shock. Anti-tumour necrosis factor antiserum (anti-TNF-alpha) and, to a lesser extent anti-SE antisera, reduced the lethality to SE in D-galactosamine-treated mice. This proposed cost-effective animal model may be used to study the immunopathological properties of natural, recombinant or mutant SE.     

Effect of cytochrome P450-dependent metabolites of arachidonic acid on the functional state of vessels]

We hoped to determine the number of pulses and energy needed to create acute ureteral perforations with four different lithotripters in a reproducible ex vivo model. A simple model was constructed to control variables in the testing such as wall thickness, intraluminal pressure, distance between the probe tip and ureter, and power delivered to tissue. Segments of domestic pig ureter were prepared and fixed in position in a normal saline (NS) bath at room temperature. We then attempted perforation with the holmium:YAG (HoL) laser, coumarin pulsed-dye laser (CdL), electrohydraulic lithotripter (EHL), and pneumatic impactor (PI) by placing the instrument probes at right angles to the ureteral wall. The ureter was filled with a methylene blue-stained solution of NS at 90 cm H2O pressure via a urodynamics catheter, and perforation was recorded on initial extravasation of dye. The endpoints measured were time to perforation and total energy required. At 0.5 mm of separation between the wall and probe, the HoL perforated the ureter in an average of 2 seconds and 0.01 kJ delivered at 5 W (10 Hz and 0.5 J/pulse). The EHL perforated at an average of 24.44 +/- 8.77 seconds and a total energy of 0.01 +/- 0 kJ. The CdL was able to perforate but at much longer intervals (257.51 +/- 99.08 seconds) and higher energy levels (12.88 +/- 4.95 kJ) on average than either the EHL or HoL. Lastly, the PI was unable to perforate the ureter in more than 6 continuous minutes of application. In addition, we found that at 2-mm separation between the HoL probe tip and the ureteral wall, acute perforation was not possible even at very high power settings. We conclude that although each endoscopic lithotripter has advantages as well as disadvantages, in this ex vivo model, it was clear that the HoL and EHL can easily perforate the ureter and must be used with vigilance. It was found that at 2 mm of separation between the probe and target, the HoL, was unable to perforate acutely. The CdL and PI were associated with a much higher safety index, and the PI was unable to produce ureteral perforation.     

Difference in inhibitory actions of products of the myeloperoxidase- catalyzed reaction on initial aggregation of activated platelets]

Response characteristics of neurons in the gustatory and visceral zone of the parabrachial nucleus (PBN) to gamma-aminobutyric acid (GABA) were examined using whole cell recordings in brain slices of the rat. Based on the recording site, neurons were divided into three groups: neurons in the dorsolateral quadrant of the PBN (DL-neurons), neurons in the dorsomedial quadrant of the PBN (DM-neurons) and neurons in the ventromedial quadrant of the PBN (VM-neurons). Recordings were made from 44 DL-, 43 DM-, 39 VM-neurons. Superfusion of GABA resulted in a concentration-dependent reduction in input resistance in 67.5% of the neurons in the PBN (73.1% of the DL-, 62.5% of the DM-, 66.7% of the VM-neurons). No obvious difference of the concentration-response curve was found among three groups. The mean reversal potential of the GABA effect was about -74 mV and no significant differences were observed among three groups of neurons. The GABA response was partly or completely blocked by the GABAA antagonist bicuculline in all neurons tested. Superfusion of the GABAA agonist muscimol resulted in a decrease of the input resistance in all neurons tested. It was concluded that GABA functions as an inhibitory neurotransmitter in both gustatory and visceral part of the PBN, mediated in part, by GABAA receptors.     

Cytochemical evidence for endogenous hydrogen peroxide generation in the neutrophils from human blood smears

We present more accurate evidence for generation of endogenous hydrogen peroxide as a result of peroxidase-endogenous hydrogen peroxide system activity in the neutrophils (Rogovin et al., 1978). The normal cytochemical reaction of the peroxidase-endogenous hydrogen peroxide system in the neutrophil peroxidasosomes after elimination of water-dissolved H2O2 by KMnO4 indicates the neutrophils on smears as a source of H2O2, rather than alcohol-formaldehyde. This is confirmed by the cytochemical reaction of peroxidase-endogenous H2O2 reaction in the neutrophils on smears prepared without fixation. The peroxidase-endogenous H2O2 system in the neutrophils on blood smears acts at pH other than peroxidase: 7.7-5.5 vs. 7.7-3.4 (basic pH range was not examined). This difference appear to be due specific features of the enzyme complexes ultimately generating H2O2.     

Reversible association of the equilibrium unfolding intermediate of lambda Cro repressor

An extended differentiated scanning calorimetry study of the wild-type Cro repressor and of its V55C mutant has revealed a significant concentration dependence of the melting profiles, even though the two polypeptide chains forming the active repressor molecule are covalently bound within the mutant. An analysis of the temperature dependencies of the partial molar heat capacity suggests that in both cases equilibrium unfolding occurs via a highly-populated intermediate state corresponding to polypeptide tetramers. The results of thermodynamic analysis are confirmed by direct glutaraldehyde cross-linking experiments. Judging by heat effects and circular dichroism data, this intermediate state regains about 50% of the ordered structure and melts co-operatively.