A cytogenetic study of the human chorion for the purpose of the prenatal diagnosis of hereditary diseases

Cytogenetical investigation of 50 diagnostic chorionic villus samples from women with a high risk of giving birth to babies with chromosomal and genic pathology, and of 128 chorionic samples obtained from medical abortions, both on the 8-12th weeks of gestation was performed by means of original direct chromosomal analysis. Chromosomal anomalies were found in 6 cases of diagnostic chorion biopsies (12%) and in 4 cases (3%) of medical abortions. The former group included 5 embryos with autosomal trisomy (4--Ts21 and 1--Ts13) and one embryo with monosomy 18. The latter group contained 2 embryos with X-chromosome monosomy and 2 other with chromosomal mosaicism. A significant prevalence of the female sex was found in the diagnostic group (sex ratio 0.56), but not in the medical abortion one (sex ratio 1.0). Analysis of routine chromosomal preparations and those after in situ hybridization with X-chromosome alfoid-probe YAP 1-10 revealed polyploidy in average in 0.8-1% chorion cells. The feasible causes of sex ratio distortion in embryos of diagnostic group and factors responsible for the rate of polyploidy are discussed. High reliability of originally elaborated direct "shaking-blotting" method of chromosomal preparations from chorionic villus samples is stressed.     

Efficiency of Transient Expression in Protoplasts of Various Potato Cultivars

Applied Biochemistry and Microbiology - The production of mesophilic protoplasts of potato (Solanum tuberosum L.) for transient gene expression is a required technological stage in the testing of...     

Plant virus infection development as affected by heavy metal stress

The work was focused on the investigation of possible dependencies between the development of viral infection in plants and the presence of high heavy metal concentrations in soil. Field experiments have been conducted in order to study the development of systemic tobacco mosaic virus (TMV) infection in Lycopersicon esculentum L. cv. Miliana plants under effect of separate salts of heavy metals Cu, Zn and Pb deposited in soil. As it is shown, simultaneous effect of viral infection and heavy metals in tenfold maximum permissible concentration leads to decrease of total chlorophyll content in experiment plants mainly due to the degradation of chlorophyll a. The reduction of chlorophyll concentration under the combined influence of both stress factors was more serious comparing to the separate effect of every single factor. Plants' treatment with toxic concentrations of lead and zinc leaded to slight delay in the development of systemic TMV infection together with more than twofold increase of virus content in plants that may be an evidence of synergism between these heavy metal's and virus' effects. Contrary, copper although decreased total chlorophyll content but showed protective properties and significantly reduced amount of virus in plants.     

Mammaglobin in peripheral blood and the tumor of breast cancer patients

Currently, no molecular biological markers do exist for early diagnosis of breast cancer. One of the possible candidates for the marker of early breast cancer is mammaglobin (MGB1) or SCGB2A2 (secretoglobin, family 2A, member 2), characterized by the maximal expression level in early breast cancer. Using the RT-PCR method MGB1 mRNA expression was examined in 57 tumor tissue samples and 57 samples of morphologically non-malignant tissue (MNT) of breast cancer (BC) patients. Specificity and sensitivity of the MGB1 mRNA assay in peripheral blood of BC patients was evaluated by nested PCR. 169 blood samples (from 95 BC patients, 22 from patients with benign breast tumors, 28 from patients with tumors of other localizations, and 24 samples from healthy donors) have been analyzed. MGB1 expression was significantly higher in BC tissue samples compared to MNT (p = 0.0019). The maximal expression level was in the samples T1 (p = 0.013), stage I BC (p = 0.037), GI (p = 0.0019). MGB1 expression positively correlated with expression of estrogen (p = 0.034) and progesterone (p = 0.0004) receptors. Sensitivity and specificity of the MGB1 mRNA assay in peripheral blood were 60.6 and 92.3%, respectively. Expression of MGB1 was higher in BC than MNT and it decreased during BC progression. The sensitivity and specificity of the MGB1 mRNA assay may be used as an additional diagnostic method.     

The use of batumin-containing disks for the rapid identification of staphylococci

The study of 467 microbial strains obtained from collections and from clinical sources revealed that microorganisms of the genus Staphylococcus were highly sensitive to batumin, a new antibiotic obtained from bacteria of the genus Pseudomonas. 378 strains of 15 Staphylococcus species proved to be highly sensitive to the diagnostic preparation "Diastaph", developed on the basis of batumin (antibiotic-impregnated discs); After 18-hour incubation the diameter of the growth inhibition zones on agar-containing culture media was 18-38 mm. Strains belonging to the genera Micrococcus, Dermacoccus, Kocuria and Kytococcus, as well as the tested representatives of other taxa (Planococcus, Streptococcus, Corynebacterium, Acinetobacter, Pseudomonas, Neisseria, the representatives of all tested genera of the family Enterobacteriaceae, fungi of the genus Candida) were insensitive to the diagnosticum. "Diastaph" permits not only the rapid identification of staphylococci pure cultures, but also the determination of their presence in association with other microbial species directly in pathological material, which makes it possible to recommend this diagnostic preparation for use in medical, veterinary and sanitary microbiology.     

Flexion-extension movements in the adult thoracic spine

The flexion-extension mobility of the thoracic spine was studied by examining 120 patients who had no complaints about the thoracic spine. Its quantitative characteristics that assess the contribution of some segments to the movements of the thoracic spine were developed. Sexual differences of the developed quantitative characteristics of the motor function of the thoracic spine were defined. The specific features of changes in the motor function were analyzed in adult females and males.     

Isoforms of Aldehyde Dehydrogenase in the Brain Structures of Rats with Different Inclinations to Ethanol Consumption

We measured the levels of activity of aldehyde dehydrogenase (AdhDH, EC 1.2.1.3) manifested at different concentrations of acetaldehyde (AcAdh) in cytosol fractions from the tissues of the hypothalamus, midbrain, and neocortex of rats preferring an ethanol solution or pure water as liquids for drinking (ethanol- and water-preferring, EP and WP groups, respectively). Two AdhDH isoforms, with a high and a low affinity for AcAdh, were identified in the above brain structures. An AdhDH-1 isoform characterized by a higher affinity for AcAdh and a low value of the apparent Michaelis constant (K _m) was found in all studied brain structures of the EP rats. An analogous AdhDH-1 isoform found in cytosol fractions from the hypothalamus and midbrain of the WP rats showed a lower affinity for AcAdh and provided a lower maximum rate of reaction (V _max). In the neocortex cytosol fractions of the rats of this group, AdhDH-1 could not be identified. In EP rats, the level of AcAdh metabolism mediated by AdhDH was noticeably higher in cytosol fractions from the hypothalamus and midbrain, as compared with that in the respective fraction from the neocortex.     

Effect of a hypertonic sucrose solution and 5-(N,N-hexamethylene)-amiloride on receptor-mediated and liquid-phase endocytosis

Hypertonic sucrose and amiloride or derivatives of the latter are commonly used to selectively inhibit clathrin-dependent (usually considered as a synonim of receptor-mediated endocytosis) or clathrin-independent endocytosis. Though these approaches are widely used in experimental practice, their limitations have not been studied in detail. In the present work, an attempt was made to evaluate possible side effects and selectivity of these agents towards the type of endocytosis. It was found that the incubation of A431 cells in 0.4 M sucrose resulted in a decrease in both intracellular accumulation and surface binding of the RME marker 125I-EGF. However, while the binding drops by about 3 times, the internalization of EGF in low concentrations was inhibited by more than 30 times, and that of high EGF concentrations by 5-10 times. It may evidence that at high EGF concentrations about 10-20% of ligand-receptor complexes can enter the cells through clathrin-independent pathway. Nevertheless, these results cannot be interpreted so unambigously, because we found that at the incubation longer than 30 min a significant portion of cells became dead or damaged, yielding about 50% of the whole population. By immunofluorescent assay, 5-(N,N-hexametylen)-amiloride commonly used to inhibit fluid phase endocytosis was demonstrated to reduce the staining of fluorescein-containing pinocytic vesicles, but it did not inhibit totally the entering of this marker. Under simultaneous stimulation of fluorescein and EGF endocytosis in the presence of the amiloride derivative, such a residual fluorescence shifted with time to the juxtranuclear region, which is characteristic of the late steps of RME. We suppose that a significant portion of extracellular fluid phase can be included in clathrin-dependent vesicles, whose formation is not disturbed by amiloride. It means that conclusions about the degree of pinocytosis inhibition are to be corrected, taking into account the constitutive clathrin-dependent endocytosis.     

The role of phosphatidylinositol-3-kinases P85/P110 and hVPS34 in endocytosis of EGF-receptor complexes

The previous data (Zheleznova et al., 2001) did not enable the authors to conclude which particular wortmannin sensitive PI-3-kinase--p85/p110 (I class PI-3-K) or hVPS34 (III class PI-3-K)--may be involved in the regulation of EGF-receptor endocytosis. In the present work, we have shown that upon stimulation of EGF-receptor endocytosis additional structures stained with antibody against p85 appear in A431 cells, but the p85-positive compartment never co-localized with EGF-receptor-containing compartments either in control or in wortmannin-treated cells. At the same time, wortmannin treatment prevented association of hVPS34 with endosomal membranes. We have also found that early endosomal markers--Rab5 and EEA1 (membrane association of the latter depends on Rab5 and hVPS34)--co-localized with EGF-receptor in the juxtranuclear region during late stages of endocytosis, both in control and upon wortmannin treatment. These observations favor our suggestions that the transition of EGF-receptors from early to late endosomes may occur directly in this juxtranuclear region and be tightly associated with the formation of so called multivesicular bodies (MVB), which are late endosomes per se. We suggest that wortmannin may have no effect on early EEA1-dependent stage of the receptor endocytosis but blocks a transition of EGF-receptor complexes into the late endosomes by inhibiting activity of hVPS34 and removing it from membranes. The hVPS34 product PI-3-K, according to the known data, is involved in the formation of internal vesicles of MVB. Accumulation of EGF-receptors in these vesicles is believed to be necessary for the receptor degradation.