Method of obtaining crystalline choleragen and choleragenoid preparations]

A new method of concentration and purification developed allows to obtain choleragen and choleragenoid preparations, homogeneous in the immunochemical analysis with regard to the culturing of vibrios producing these substances on the available nonsynthetic nutrient medium. Crystalline choleragen and choleragenoid preparations were obtained from highly purified samples. Choleragen possessed enterotoxic and skin premeability factors; choleragenoid shows no biological activity.     

Rational method of obtaining sera with a high titre of virus-neutralizing antibodies. Report 2]

In addition to report I (ZHMEI, 1977, No. 1) a study was made of 9 more schemes of rabbit immunization with the poliomyelitis virus, type I, for the purpose of obtaining the neutralizing sera of high titre. Vitamins A and C were used in the experiments in the capacity of the activators of the organism reaction; Freund's adjuvant of different make was tested; different reimmunization periods and different amounts of the adjuvant were administered. Titration of rabbit sera in the process of immunization and reimmunization showed immunization into the lymph nodes with the subsequent single reimmunization in one month to be the most effective and economical method of obtaining high effective sera.     

The use of metal microelectrodes in broad-band recording.

We checked to what extent the voltage-current relationship of a microelectrode is linear. In the linear domain we measured the impedance characteristic of the electrode. We measured the frequency response curve and the phase characteristic of the electrode and amplifier system.     

Chemical modification of alpha-chymotrypsin for obtaining high transesterification activity in low water organic media

Alpha-chymotrypsin was made more hydrophilic by modifying 11 (out of 16) ε-amino groups with pyromellitic dianhydride. The hydrophilic preparation was precipitated with n-propanol. This preparation gave significantly higher initial rates at the optimum a_w (127.51 nmol mg^?1 min^?1 in n-octane and 21.30 nmol mg^?1 min^?1 in acetonitrile at a_w=0.33) compared with the lyophilized preparation (53.50 nmol mg^?1 min^?1 in n-octane and 0.26 nmol mg^?1 min^?1 in acetonitrile at a_w=0.97). FT-IR showed that the precipitate of modified alpha-chymotrypsin has a higher content of alpha-helices and beta-sheets compared to the lyophilized powder.     

Blood viscosity factor in persons with high and low risk of ischemic heart disease]

In the years 1986-1987, the blood viscosity factor, the content of haemoglobin in erythrocytes, the concentration of glucose in blood, the lipids and the blood coagulation system were examined in 180 subjects. They were divided into three groups according to the exposure to risk factors: group performing light manual work (L), group performing hard manual work (C) and group of engine drivers (M). No statistically significant differences in regard to age, employment period, number of cigarettes smoked, as well as arterial systolic and diastolic blood pressure were found between the subjects. Workers from group M had the highest body weight (P > 99%) and increased concentration in blood of triglycerides (P > 99% and Apo B (P > 99%. Subjects from group C had the lowest concentration of cholesterol in blood (P > 99%) and the smallest number of members with hypertensions (3.8%) and overweight (7.5%). Group L included the highest percentage of persons with arterial hypertension (17.5%), the highest, among all examined, blood viscosity factor determined at the coagulation rate of 18.6 s-1, and the lowest prothrombin factor (P > 99%).     

Optimum utilization of sewage sludge of low and high metal content for grain production on arid lands

Summary Two municipal sludges, one from a highly industrialized city, Chicago, Il, and another from a little industrialized, highly agricultural area, Tucson, AZ are compared for winter barley production on Pima c 1 (Typic torrifluvent). Both sludges were responsible for highly significant additions of Zn, Cu, Ni, Cd and P to the soil each year when applied at the rates of 100 mt/ha singly and 20 mt/ha each year for 4 years. Nitrogen responses for barley straw and grain were observed from both sludges. Tucson sludge appears to be attractive as a potential fertilizer, not only as an NPK source, but also for its organic matter and minimal amounts of heavy metals. The Chicago sludge with relatively high levels of heavy metals, particularly Cd, appears poorly suited as a fertilizer, if used for an extended period of time, because of the plant's tendency to take up elevated levels of certain heavy metals. Some parts of barley plants proved to be a better indicator of heavy metal uptake and concentration than others. The diagnostic-tissue test promises to be a useful tool to warn against undesirable accumulation of heavy metals. Fortunately, when compared with other plant parts, the heavy metal in grain was the least altered as a result of continued sewage sludge use on arid land. The soil's neutral to slightly alkaline pH and the presence of lime throughout the soil profile appeared to be critical factors in keeping plant uptake of heavy metals relatively low as compared with soils of other climates.     

Reduced capacitative calcium entry correlates with vesicle accumulation and apoptosis

A preneoplastic variant of Syrian hamster embryo cells, sup(+), exhibits decreased endoplasmic reticulum calcium levels and subsequently undergoes apoptosis in low serum conditions (Preston, G. A., Barrett, J. C., Biermann, J. A., and Murphy, E. (1997) Cancer Res. 57, 537-542). This decrease in endoplasmic reticulum calcium appears to be due, at least in part, to reduced capacitative calcium entry at the plasma membrane. Thus we investigated whether inhibition of capacitative calcium entry per se could reduce endoplasmic reticulum calcium and induce apoptosis of cells. We find that treatment with either SKF96365 (30-100 microM) or cell-impermeant 1,2-bis(o-amino-5-bromophenoxy)ethane-N,N,N', N'-tetraacetic acid (5-10 mM) is able to induce apoptosis of cells in conditions where apoptosis does not normally occur. Because previous work has implicated vesicular trafficking as a mechanism of regulating capacitative calcium entry, we investigated whether disruption of vesicular trafficking could lead to decreased capacitative calcium entry and subsequent apoptosis of cells. Coincident with low serum-induced apoptosis, we observed an accumulation of vesicles within the cell, suggesting deregulated vesicle trafficking. Treatment of cells with bafilomycin (30-100 nM), an inhibitor of the endosomal proton ATPase, produced an accumulation of vesicles, decreased capacitative entry, and induced apoptosis. These data suggest that deregulation of vesicular transport results in reduced capacitative calcium entry which in turn results in apoptosis.     

Method for obtaining known low concentrations of mustard (H) or lewisite (L) gas in air

Constant small quantities (0.1 to 100 micrograms per hour) of mustard (H) or lewisite (L) gas may be obtained by allowing the vapor to diffuse through a porous alundum plug of suitable dimensions. By regulating the rate of flow of air past the plug known concentrations of the gases in air may be obtained.     

Method of obtaining enzymatic preparations of lipase from the fungi of the genus Geotrichum under semi-industrial conditions]

A method of manufacturing stable enzymic preparations of lipase from fungi Geotrichum candidum and G. asteroides under semi-industrial conditions has been developed. The paper describes the preparation of the inoculate, fermentation nutrient medium, scheme of cultivation and isolation of the raw enzyme with a yield of 31.2%.