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Low cost scintillation detectors as compared with HPGe detectors are considered to be one of most important radiation detection tools. Therefore, these detectors can be manufactured in different shapes and work at room temperature without any cooling systems, which added an extra advantage to it. This work presents a study of a cubic detector with a rectangular cavity in different experimental setup geometries, using standard point-like gamma-ray sources, where the efficiency of the detector in these geometries was the target to be studied. According to this aim, the data from the experimental measurements was used to determine the detector efficiency. An analytical calculation of the detector efficiency was done by using a new mathematical expression, this mathematical expression depends on the efficiency transfer technique and effective solid angle calculations. To support the mathematical model, the source-to-detector arrangement was simulated by Geant4 Monte Carlo code. All the compared efficiency results were found to be promising and trusted based on the calculated deviation percentages., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In this article, we present a new industrial gamma-ray imaging system. This system takes advantage of a time-modulated random coded aperture (TMRCA). The gamma-ray detector coupled to the TMRCA can be position-sensitive or non-position-sensitive. The TMRCA imaging system could offer the ability to identify radioactive sources without losing spatial resolution. With a non-position-sensitive BGO detector, a prototype TMRCA imaging system was constructed. The prototype system was investigated with two gamma-ray sources ( 137 Cs, 60 Co) and a 238 Pu-Be neutron source, which was placed in a paraffin moderator to produce an extended source. The experimental results suggest that the TMRCA imaging system offers the opportunity to achieve high spatial-energy resolution cost-effectively for high-energy gamma rays.

The first experience in introducing the nucleic acid amplification technique (NAT) in an Indian blood service as compared with the established European practice is analyzed. Examination of 12,224 donor blood samples revealed 217 (1.78%) persons with markers of infections, including 8 (0.065%) persons only with markers of viral genome, without serological signs of infections. In India, enzyme immunoassay-negative NAT-positive donations were tens of times more detectable than in the developed countries, which is associated with the epidemiological features and the large (more than 50%) proportion of paid donors. By taking into account the fact that 4.6% of the preserved blood doses are annually rejected as defective in the Russian Federation, as evidenced by the screening of markers of infections, the introduction of NAT may be expected to reveal a large proportion of donors in the period of both a "seronegative window" and chronic carriers of hepatitis B virus with its blood content. Both intralaboratory monitoring using the certified standards and the laboratory work quality system as a whole are a necessary condition for introducing NAT into a blood service.

The concentration of blood fibronectin and the state of the phagocytic function in the liver was studied in 19 patients with an emergency pathology of the abdominal cavity complicated by the infective-toxin shock and polyorganic insufficiency. Patients with severe abdominal pathology had a considerably decreased level of circulating fibronectin, disturbed phagocytic function of the liver and development of the hypercatabolic state. Hypofibronectinemia was accompanied by polyorganic disorders, systemic bacteriotoxemia and disseminated intravascular coagulation. Causes of hypofibronectinemia and its role in pathogenesis of systemic complications in patients with emergency abdominal pathology are discussed.

Ajoene, (E,Z)-4,5,9-trithiadodeca-1,6,11-triene-9-oxide, isolated from extracts of garlic (Allium sativum) has been previously shown to inhibit platelet aggregation by inactivating allosterically the platelet integrin, GP IIb/IIIa. The structural and functional similarity of integrins led the authors to suggest that ajoene may also inhibit adhesive interactions and fusion of leukocytes. Synthetic stereoisomers of ajoene synthesized by the authors exhibited equal antiaggregatory activities (IC100 approximately 50 microM for platelets; IC100 approximately 10 microM for fMLP-stimulated neutrophils). Racemic ajoene inhibited the fusion of H9 cells with HIV-infected H9:RF cells (IC50 approximately 45 microM; 16 h of incubation) and also exhibited a degree of antiviral activity (IC50 approximately 5 microM as assessed by inhibition of HIV-1/CEM/Lav 1 Bru replication in CEM13 cells; m. o. i. 0.1; 72 h). A considerable increase in the latter became evident when the compound was administered in aliquots of 50 microM per 12 h of incubation (inhibition by 30%; total concentration 0.25 microM; 72 h).(ABSTRACT TRUNCATED AT 250 WORDS)

The Arg-Gly-Asp (RGD) tripeptide and ajoene were used for studying the role of adhesive receptors in the respiratory burst. Activation of the respiratory burst was examined by using luminol-dependent and lucigenin-dependent chemiluminescence. Recently, it was shown that ajoene, (E, Z)-4,5,9-trithiadodeca-1,6,11-trien-9-oxide, a substance isolated from garlic extract, inhibits the binding of fibrinogen to activated platelets by direct interaction with fibrinogen receptor (Apitz-Castro, R., Lederma, E., Escalante, J. and Jain, M.K. (1986) Biochem. Biophys. Res. Commun. 141, 145-150). Taking into consideration the structural and functional similarity of integrins, it would be reasonable to assume that ajoene as well as RGD can inhibit adhesive interactions of human neutrophils. We have shown that the effect of various activators on the respiratory burst was abolished by ajoene or RGD treatment. The inhibitory effect of RGD and ajoene was dose-dependent. The treatment of neutrophils with antiserum against human plasma fibronectin inhibited the respiratory burst in response to formyl-methionyl-leucylphenylalanine (fMLP) and phorbol 12-myristate 13-acetate (PMA). This effect is dose-dependent and reversible with the addition of fibronectin. These data indicate that the respiratory burst in human neutrophils is mediated by the integrin family of receptors and that interactions between the extracellular matrix fibronectin and cells are necessary for the respiratory burst.

Storage of anticoagulated whole blood leads to the activation of platelets and granulocytes, formation of aggregates, lysis of cells, various thrombogenic substances, including proteolytic enzymes. Transfusion of the blood may cause capillary occlusion, intravascular coagulation, renal and hepatic dysfunction. Gel-silicagel affinity+ chromatography of the anticoagulated whole blood was shown to result in selective sorption of plasma fibrin. Preactivated platelets and granulocytes were also removed by interaction of cell fibronectin receptors with immobilized fibronectin. The residual platelets and granulocytes lost their ability to storage-induced activation and remained viable for at least 48 hours at 4 degrees C.

Fibronectin is a unique polyfunctional regulator of different cells. Its property is due to the presence of many domains and cell integrin receptors which recognize the RGD sequence.

The reported data of the latest 5-7 years point to a high reactivity of human and animal blood platelets depending on the physiological status (age, sex, season, time of the day, diet, physical and psychoemotional tension and so forth) and in disease (cardiovascular diseases, intoxication and others). In view of this fact platelets (in physiology and pathology) may serve as a highly sensitive and convenient test system not only for hemostatic blood potential estimation but also for the determination of physiological and pathological shifts in other systems of the body.

The diagnostic value of determination of plasma fibronectin in chronic hepatic diseases was examined on the basis of the data available in the literature and the authors' own results of studies. The procedure for measuring fibronectin in healthy subjects and patients with hepatic cirrhoses and chronic persistent hepatitis is briefly outlined. Possible mechanisms of fibronectin level alterations are discussed in these pathological processes.

It was shown that the buoyant density of DNA isolated from lymphocyte incubation media as well as from blood plasma of healthy patients and patients with chronic lympholeukemia (CLL) using the SDS-phenol method with subsequent ultracentrifugation in a cesium trifluoroacetate density gradient is 1.59-1.60 and 1.60-1.63 g/ml, respectively. Using electrophoresis in 0.6% agarose gel, it was found that the DNA excreted by lymphocytes from healthy patients and CLL patients is a high molecular weight fraction comprising 21,000 nucleotide pairs. This DNA fragment contains 90-95% of [3H]thymidine used for the labeling of DNA excreted by lymphocytes from healthy patients and patients with CLL. No traces of [3H]thymidine were found in the middle part of the agarose gel containing the diffuse material bound to ethidium bromide.

Comparative trials of two tocolytic preparations, salbupart (Polfa) and partusisten, showed their high efficacy (75 and 80 per cent, respectively). The success of management depends on the outcome of the preceding pregnancies, the course of current pregnancy in the 1st and 2nd trimesters, the cervical status, and extent of therapy. Normalization of cAMP levels concurrent with reduced force of uterine contractions and elimination of clinical signs of threatening pregnancy termination are also indicative of benefits of tocolytic therapy.

Possible use of ethidium bromide immobilized on polyacrylamide gel for DNA extraction from biological media, e.g., cell lysates and blood serum, is discussed. The ability of the affinity gel to cause fractionation of single- and double-stranded DNA is demonstrated.

In vitro and in vivo studies showed that methylation of homologous DNA in nuclear homogenates of rat bone marrow is controlled by cyclic nucleotides and some hormones. The cyclic nucleotides and their dibutyryl analogs inhibited homologous methylation of DNA in the presence and absence of phosphodiesterase inhibitors. In the presence of Ca2+ the inhibiting effect of the nucleotides was more pronounced. Prostaglandins inhibited DNA methylation in a weaker degree while insulin and erythropoietin had a stronger effect in comparison with the nucleotides. Histamine stimulated DNA methylation, whereas acute hypoxic hypoxia caused a reduction in the rate of DNA methylation.

The action of calmodulin (CM) given in doses of 10(-5)-10(-8) M on lymphocyte proliferation in healthy subjects was studied. All the test doses of CM produced a stimulant effect 72 h after the lymphocyte incubation was commenced. The rate of 3H-thymidine incorporation experimentally was 1.5-3 times higher than in the control. It is assumed that the release of CM in the foci of tissue injury or inflammation may serve one of the factors stimulating lymphocyte proliferation in an individual focus.

It has been first demonstrated that DNA concentration in the plasma of healthy donors was 5 to 30 mu kg per I ml of plasma or 10-50% of DNA content in leukocytes contained in the same blood volume. DNA plasma concentration was determined by registering DNA-bisbenzimide complex fluorescence in supernatant derived from plasma containing 10% NaCl upon heating for 2-3 min at 100 degrees C. The method is simple, specific and permits the determination of DNA concentrations in 0.05-0.1 ml of plasma samples.

Unlike known cytostatics, 5'-deoxy-5'-S-isobutyladenosine (SIBA) does not inhibit proliferative activity of hemopoietic stem cells of intact bone marrow. On the contrary, it raises CFUs number of 15-28% in vitro and in vivo. SIBA inhibits by 40% the 3',5'-cAMP-induced increase in CFUs proliferation.

It has been shown in experiments on cats that during complete blood replacement by polyglucin and in oxygen respiration, the life of the animals can be supported for 8-9 hours. The control animals which inspired the atmospheric air rapidly died. The animals' survival was promoted by high partial oxygen pressure in the air inspired, by a greater blood flow and constant volume of the circulating blood.