Biopolymer of alginate nature with a predominance of L-guluronic acid

Highly viscous polysaccharide (250–350 kDa) of an alginate nature with a predominance of α-L-guluronic acid (M/G = 0.22) was obtained from Azotobacter vinelandi. The yield of polysaccharide was 20.5 ± 0.5 g/l when cultured in a medium containing molasses at a viscosity of the cultural liquid of over 30000 cSt. The biopolymer is stable at pH 4.0–9.0 in a wide temperature range and well soluble in highly mineralized water; it retains a high viscosity level and can be used in the petroleum industry for enhanced oil recovery.     

Experience with epidemiologic studies of pyocyaneus infections. I. Feasibility of using serotypes and antibiotic resistance as a epidemiologic label for clinical strains]

The authors carried out serological typing of 98 Pseudomonas aeruginosa strains, isolated from patients of burn department of the Sklifosovsky First Aid Institute in January-July, 1974, and of 215 strains obtained from other sources; their sensitivity to 13 antibiotics was determined. Pseudomonas aeruginosa cultures isolated from the patients were typed with O-sera of 10 serological types. The presence of several hospital strains of Pseudomonas aeruginosa was found by means of serological typing; along with these there were revealed cultures of this causative agent sporadically appearing in the department. Sensitivity to some antibiotics could serve as an additional criterion for differentiation of Pseudomonas aeruginosa strains of the same serological type.     

Charge changes in sarcoplasmic reticulum and Ca2+-ATPase induced by calcium binding and release: a study using lipophilic ions

Changes in the charge of sarcoplasmic reticulum (SR) vesicles are studied using lipophilic ions, which are adsorbed by the membrane phase. Upon addition of MgATP, phenyldicarbaundecaborane (PCB-) and tetraphenylboron (TPB-) are taken up by the SR vesicles, while tetraphenylphosphonium (TPP+) is released into the water phase. The PCB- uptake occurs as well under conditions when SR membrane is shunted by high Cl- concentration. MgATP induces minor additional binding of PCB- in the presence of oxalate and it is followed by release of the lipophilic anion from the vesicles. EGTA partly reverses the ATP effect, and calcium ionophore A23187 plus EGTA reverses it completely. Vesicles that were preliminarily loaded by Ca2+ demonstrated higher passive and lower ATP-dependent PCB- binding. Activation of isolated Ca2+-ATPase in the presence of 0.1 mM EGTA results in PCB- release into the medium and additional TPP+ binding to the enzyme. We suggest that the redistribution of the lipophilic ions between the water phase and SR membrane reflects charge changes in Ca2+-binding sites inside both SR vesicles and Ca2+-ATPase molecules in the course of Ca2+ translocation.     

Change in charge of the erythrocyte membrane during exposure to a pulsed electromagnetic field]

By means of hydrophobic anion phenyldicarbaundecaboron electrophoresis in PAA gels and filtration through "Millipore" filters an increase of the total membrane charge and decrease in the amount of membrane-bound proteins (actin, glyceraldehyde-3-phosphatedehydrogenase) after erythrocyte ghosts exposition in pulsed electromagnetic field (PEMF, 1-10 Hz pulse frequency, 24 mTesla) were demonstrated. The effects of PEMF are explained by the changes in the distribution of electrostatic charges near the membrane protein-protein binding sites.     

Mechanism of action of tetracycline on the functional state of the adrenal cortex]

The mechanism of stimulation of the adrenal cortex function by tetracycline was studied on albino rats. It was shown that tetracycline administered orally in a dose of 200 mg/kg regularly induced an increase in the corticosterone levels in the peripheral blood of the animals by the 15th day of the antibiotic use. It was shown on the animals with an experimentally suppressed function of the hypophysis by prolonged administration of hydrocortisone acetate that tetracycline primarily stimulated the hypophysis function resulting in production and excretion of increased amounts of the adrenocorticotropic hormone into the blood. The hormone increased the production of corticosterone in the adrenal glands which resulted in its higher levels in the peripheral blood.     

Viability and proliferative activity of a Chinese hamster cell culture exposed to nitrosoureas in exponential and stationary growth phases

The lethal effect of antitumor nitrosourea chloroethyl derivatives on proliferating (exponential phase of growth) and non-proliferating (stationary phase of growth) cells is observed at a concentration 5-fold less than that of methyl derivatives revealed by the colony-formation technique. 1,3-bis(2-chlororoethyl)-1-nitrosourea is equally effective towards proliferating and non-proliferating cells, but chlorozotocin exerts a primary cytotoxic effect on proliferating cells. 1-methyl-1-nitrosourea at low concentration causes death more readily of proliferating cells than non-proliferating ones. However, studies on proliferative activity during the first hours after treatment with 1-methyl-1-nitrosourea revealed drug sensitivity in cells being at the early stationary phase of growth.     

Severe Painful Vaso-Occlusive Crises and Mortality in a Contemporary Adult Sickle Cell Anemia Cohort Study

Background

Frequent painful vaso-occlusive crises (VOCs) were associated with mortality in the Cooperative Study of Sickle Cell Disease (CSSCD) over twenty years ago. Modern therapies for sickle cell anemia (SCA) like hydroxyurea are believed to have improved overall patient survival. The current study sought to determine the relevance of the association between more frequent VOCs and death and its relative impact upon overall mortality compared to other known risk factors in a contemporary adult SCA cohort.

Methods

Two hundred sixty four SCA adults were assigned into two groups based on patient reported outcomes for emergency department (ED) visits or hospitalizations for painful VOC treatment during the 12 months prior to evaluation.

Results

Higher baseline hematocrit (p = 0.0008), ferritin (p = 0.005), and HDL cholesterol (p = 0.01) were independently associated with 1 or more painful VOCs requiring an ED visit or hospitalization for acute pain. During a median follow-up of 5 years, mortality was higher in the ED visit/hospitalization group (relative risk [RR] 2.68, 95% CI 1.1-6.5, p = 0.03). Higher tricuspid regurgitatant jet velocity (TRV) (RR 2.41, 95% CI 1.5-3.9, p < 0.0001), elevated ferritin (RR 4.00, 95% CI 1.8-9.0, p = 0.001) and lower glomerular filtration rate (RR=2.73, 95% CI 1.6-4.6, p < 0.0001) were also independent risk factors for mortality.

Conclusions

Severe painful VOCs remain a marker for SCA disease severity and premature mortality in a modern cohort along with other known risk factors for death including high TRV, high ferritin and lower renal function. The number of patient reported pain crises requiring healthcare utilization is an easily obtained outcome that could help to identify high risk patients for disease modifying therapies.

Trial Registration

ClinicalTrials.gov NCT00011648 http://clinicaltrials.gov/     

A Group of Hypermethylated miRNA Genes in Breast Cancer and Their Diagnostic Potential

Molecular Biology - miRNA genes play an important role in cancer pathogenesis, while they may be suppressed by hypermethylation. Here, we assess the diagnostic potential of a group of...