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81.
The results of identification of 710 clinical strains of anaerobic microorganisms isolated from the pathological foci of patients with maxillofacial diseases are presented. The species composition of the microflora associations in the cases with abscesses, phlegmon, lymphadenitis, osteomyelitis and parodontitis is described. Along with a high frequency of nonsporulating anaerobes, staphylococci, microaerophilic streptococci and in the cases with parodontitis actinomycetes, Bacillus licheniformis and Bacillus coagulans strains (1.6-15% of the isolated strains) were first detected in cases with various forms of the disease. Two groups of the drugs effective against the anaerobes were identified by the data on the antibiotic sensitivity. The lowest MICs along with the activity broad spectrum were defined for gramicidin, levomycetin and nitazol.  相似文献   
82.
The mutant strain Azospirillum brasilenseSp7.2.3 with impaired lectin activity exhibited poorer cell aggregation than its parent strain A. brasilenseSp7(S) both in the exponential and stationary growth phases. The pretreatment of bacterial cells with the specific haptens (L-fucose and D-galactose) of a lectin located at the cell surface of the mutant strain was found to inhibit the aggregation of azospirilla. The specific binding of the A. brasilenseSp7(S) lectin to the extracellular polysaccharide-containing complexes of this strain was revealed by dot immunoblotting on nitrocellulose membrane filters. The interaction of the lectins of A. brasilense75, A. brasilenseSp7, and A. lipoferum59b with the polysaccharide-containing complexes that were isolated from these strains was not specific. No interstrain cross-interaction between the exopolysaccharides and lectins of azospirilla was found. A coflocculation of A. brasilenseSp7 cells with Bacillus polymyxa1460 cells was shown. The involvement of autogenous lectins in the aggregation of bacterial cells is discussed.  相似文献   
83.
Selective labeling of barstar by the stable (15)N isotope of the valine residue with high selectivity of the label incorporation resulting from the process of gene expression in Escherichia coli BL21(DE3) has been optimized. We have shown that alpha-aminooxyacetic acid (AOAA) significantly reduces the isotope redistribution, thus increasing the selectivity of (15)N incorporation into the synthesized protein, as detected by 2D-NMR. Quantitative measurements were used to determine the selectivity for the incorporation of isotope-labeled valine residue, which was 96% in the case using AOAA. Studies of the dynamics of barstar synthesis showed that no suppression of barstar yield is observed under the regulation of the T7 polymerase expression system by isopropylthio-beta-D-galactoside (IPTG) and rifampicin using AOAA.  相似文献   
84.
The effect of methyltestosterone given with feed during one and two months on the state of gonads, the level of thyroid, and sex steroid hormones in blood and on rheoreaction is studied in juvenile rainbow trout Parasalmo mykiss (=Oncorhynchus mykiss) raised under unfavorable conditions (tropics, Vietnam). In comparison with the control, in the experimental group, the part of sterile specimens was higher (83 vs. 35%), the part of males was lower (17 vs. 40%), while females and hermaphrodites were absent. At prolonged starvation (12 days), the experimental specimens demonstrated lower increase of the level of thyroid and sex steroid hormones in blood than that in the control specimens. Methyltestosterone modified the behavior of rainbow trout in water flow: delivery of the hormone in food during 1 month increased the part of fish moving against the flow and suppressed movement both upstream and downstream during 2 months. Thus, methyltestosterone negatively influences the physiological condition and adaptation capacity of rainbow trout.  相似文献   
85.
86.
A study was made of the effect of direct single exposure to beta-radiation of 0.5, 5, 10, 20, 30, and 50 Gy on development and reproduction of Aphis fabae Scop. (Aphididae, Homoptera). The numbers of bean aphid are prognosticated with regard to the radiation dose applied.  相似文献   
87.
Peripheral alpha1,3-fucosylation of glycans occurs by the action of either one of five different alpha1,3-fucosyltransferases (Fuc-Ts) cloned to date. Fuc-TVI is one of the alpha1,3-fucosyltransferases which is capable to synthesize selectin ligands. The major alpha1, 3- fucosyltransferase activity in human plasma is encoded by the gene for fucosyltransferase VI, which presumably originates from liver cells. While the sequence, chromosomal localization, and kinetic properties of Fuc-TVI are known, immunocytochemical localization and trafficking studies have been impossible because of the lack of specific antibodies. Here we report on the development and characterization of a peptide-specific polyclonal antiserum monospecific to Fuc-TVI and an antiserum to purified soluble recombinant Fuc-TVI crossreactive with Fuc-TIII and Fuc-TV. Both antisera were applied for immunodetection in stably transfected CHO cells expressing the full-length form of this enzyme (CHO clone 61/11). Fuc-TVI was found to be a resident protein of the Golgi apparatus. In addition, more than 30% of cell-associated and released enzyme activity was found in the medium. Maturation and release of Fuc-TVI was analyzed in metabolically labeled CHO 61/11 cells followed by immunoprecipitation. Fuc-TVI occurred in two forms of 47 kDa and 43 kDa bands, while the secreted form was detected as a 43 kDa. These two different intracellular forms arose by posttranslational modification, as shown by pulse-chase experiments. Fuc-TVI was released to the supernatant by proteolytic cleavage as a partially endo-H resistant glycoform.   相似文献   
88.
Akentrogonid rhizocephalans morphologically resembling the genus Thompsonia are revised as a result of examination of new material. The species concerned are all obligatorily colonial and have ovoid or cylindrically shaped externae with a terminal stalk and a much reduced anatomy. A numerical cladistic analysis of all Rhizocephala Akentrogonida using the Hennig 86 program leads to a redefinition of the Thompsoniidae HOeg and Rybakov, 1992. Autapomorphies for the Thompsoniidae are primarily the morphology of the attachment to the host and the total absence of a mesentery. The cladistic analysis refutes that the Thompsoniidae should have a plesiomorphic morphology and branch off very low on the rhizocephalan phylogeny. The family now comprises four genera: Pottsia gen. n. (monotypic), Diplothylacus gen. n. with two species, Thompsonia Kossmann with five species. A revived and redefined Thylacoplethus Coutière includes eight species. The genera are distinguished by the location of the spermatogenic tissue, the site where the eggs are fertilized, the presence or absence of a mantle pore and the way it is formed, the number or absence of oviducts, and the number of cuticular annuli on the stalk. All 16 species, of which six are new to science, are described when necessary, and, if possible, illustrated. A phylogeny for the redefined family is proposed. Thylacoplethus is morphologically closest to the hypothetically ancestral thompsoniid and is likely paraphyletic. The new genus Polysaccus with two species, one of them new to science, and the monotypic genus Pirusaccus Lützen resemble thompsoniids in externa morphology and in being obligatorily colonial.  相似文献   
89.

Background

Glucose restriction in cells increases the AMP/ATP ratio (energetic stress), which activates the AMPK/p53 pathway. Depending upon the energetic stress levels, cells undergo either autophagy or cell death. Given that the activated p53 induces the expression of IFI16 protein, we investigated the potential role of the IFI16 protein in glucose restriction-induced responses.

Methodology/Principal Findings

We found that glucose restriction or treatment of human diploid fibroblasts (HDFs) with the activators of the AMPK/p53 pathway induced the expression of IFI16 protein. The induced levels of IFI16 protein were associated with the induction of autophagy and reduced cell survival. Moreover, the increase in the IFI16 protein levels was dependent upon the expression of the functional ATM protein kinase. Importantly, the knockdown of the IFI16 expression in HDFs inhibited the activation of the ATM/AMPK/p53 pathway in response to glucose restriction and also increased the survival of HDFs.

Conclusions/Significance

Our observations demonstrate a role for the IFI16 protein in the energetic stress-induced regulation of autophagy and cell survival. Additionally, our findings also indicate that the loss of IFI16 expression, as found in certain cancers, may provide a survival advantage to cancer cells in microenvironments with low glucose levels.  相似文献   
90.
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