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Lung alveoli are coated by a thin layer of extracellular material rich in anionic charges. The nature of this acid layer and its relationship to the phospholipid surfactant are not known. We investigated the possible presence of sialic acid groups by light and electron microscopy in tissues from normal fetal and adult lungs, using neuraminidase treatment followed by staining with the galactose-binding lectin from peanut, labeled with peroxidase. Our results showed that adult lung does not bear peanut lectin-reactive sites but that a very thin and distinct reactive layer becomes evident after neuraminidase treatment, especially on type II pneumocytes. In fetal lung, the entire surface of the developing respiratory tree is outlined by a strongly peanut lectin-reactive layer even if neuraminidase digestion is not performed. We conclude that the acid coat of the alveolar lining is in part composed of sialic acid residues and that sialic acid is added to the fetal lung as the alveoli mature.  相似文献   
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A child with normal growth and development and the abnormal karyotype 46,XY,17ps, was analyzed using molecular probes localized to 17p13. The results indicated the presence of two copies of the probes YNZ22.1 (D17S5) and YNH37.3 (D17S28), previously shown to be deleted in all Miller-Dieker (MDS) patients studied. However, the patient was hemizygous for probe p144D6 (D17S34), which is absent in approximately 75% of the MDS patients. As the patient is active at 9 months of age, with no clinical signs of MDS, the results confirm that the absence of locus D17S34 does not lead to the phenotypic expression of MDS. Furthermore, this deletion should assist in defining the distal limits of this contiguous gene syndrome.  相似文献   
4.
Summary Five different soils varying in physico-chemical properties were used for studying the persistence and degradation of carboxin and oxycarboxin. In one soil only both fungicides were degraded with accumulation of ammonium and nitrite. Under the conditions of forced circulation of air and continuous perfusion, oxycarboxin was found to be more susceptible to degradation than carboxin. Under simulated conditions of rice fields, conversion of carboxin to its sulphoxide and to a non-toxic derivative of oxycarboxin could only be seen in all the soils.The role of clay, humus and organic matter as protectants of fungicides against degradation indicated that the intermediary compound carboxin sulphoxide was strongly adsorbed probably on organic and inorganic colloids of most of the soils. Organic matter free soils delayed the degradation. Carboxin was rapidly converted to its sulphoxide on three forms of monoionic clays whereas oxycarboxin was transformed to an unidentified derivative.Part of Ph.D. thesis submitted to UAS, Bangalore-65.  相似文献   
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Rumen microorganisms play an important role in ruminant digestion and absorption of nutrients and have great potential applications in the field of rumen adjusting, food fermentation and biomass utilization etc. In order to investigate the composition of microorganisms in the rumen of camel (Camelus dromedarius), this study delves in the microbial diversity by culture-independent approach. It includes comparison of rumen samples investigated in the present study to other currently available metagenomes to reveal potential differences in rumen microbial systems. Pyrosequencing based metagenomics was applied to analyze phylogenetic and metabolic profiles by MG-RAST, a web based tool. Pyrosequencing of camel rumen sample yielded 8,979,755 nucleotides assembled to 41,905 sequence reads with an average read length of 214 nucleotides. Taxonomic analysis of metagenomic reads indicated Bacteroidetes (55.5 %), Firmicutes (22.7 %) and Proteobacteria (9.2 %) phyla as predominant camel rumen taxa. At a finer phylogenetic resolution, Bacteroides species dominated the camel rumen metagenome. Functional analysis revealed that clustering-based subsystem and carbohydrate metabolism were the most abundant SEED subsystem representing 17 and 13 % of camel metagenome, respectively. A high taxonomic and functional similarity of camel rumen was found with the cow metagenome which is not surprising given the fact that both are mammalian herbivores with similar digestive tract structures and functions. Combined pyrosequencing approach and subsystems-based annotations available in the SEED database allowed us access to understand the metabolic potential of these microbiomes. Altogether, these data suggest that agricultural and animal husbandry practices can impose significant selective pressures on the rumen microbiota regardless of rumen type. The present study provides a baseline for understanding the complexity of camel rumen microbial ecology while also highlighting striking similarities and differences when compared to other animal gastrointestinal environments.  相似文献   
7.

Background

Bacteriocins are antimicrobial peptides that are produced by bacteria as a defense mechanism in complex environments. Identification and characterization of novel bacteriocins in novel strains of bacteria is one of the important fields in bacteriology.

Methodology/Findings

The strain GI-9 was identified as Brevibacillus sp. by 16 S rRNA gene sequence analysis. The bacteriocin produced by strain GI-9, namely, laterosporulin was purified from supernatant of the culture grown under optimal conditions using hydrophobic interaction chromatography and reverse-phase HPLC. The bacteriocin was active against a wide range of Gram-positive and Gram-negative bacteria. MALDI-TOF experiments determined the precise molecular mass of the peptide to be of 5.6 kDa and N-terminal sequencing of the thermo-stable peptide revealed low similarity with existing antimicrobial peptides. The putative open reading frame (ORF) encoding laterosporulin and its surrounding genomic region was fished out from the draft genome sequence of GI-9. Sequence analysis of the putative bacteriocin gene did not show significant similarity to any reported bacteriocin producing genes in database.

Conclusions

We have identified a bacteriocin producing strain GI-9, belonging to the genus Brevibacillus sp. Biochemical and genomic characterization of laterosporulin suggests it as a novel bacteriocin with broad spectrum antibacterial activity.  相似文献   
8.
The effects of a progesterone antagonist ZK 98.734 on release of bioactive luteinizing hormone (LH) and testosterone were studied in adult male common marmosets by using the following experimental protocols: (1) the blocking of the nocturnal rise in testosterone levels by ZK 98.734, (2) the pharmacodynamic effects of ZK 98.734 on testosterone and LH levels, (3) the reversal of ZK 98.734-induced decrease in testosterone by treatment with human chorionic gonadotropin (hCG), and (4) the blocking of estradiol-induced positive feedback release of LH by ZK 98.734. Sixteen adult male common marmosets were used for different experiments after resting them for at least 4 wk between experiments. Testosterone and bioactive LH levels were measured by specific radioimmunoassay and in vitro bioassay methods, respectively. Treatment (i.m.) of male common marmosets (n = 6/group) with ZK 98.734 (1 mg or 5 mg/day) at 1700 h for 3 consecutive days significantly (p less than 0.05) suppressed the nocturnal (2200 h) rise in testosterone levels. The effects of the two doses were not dose-related; however, the decrease on the first day of treatment was more pronounced with the 5-mg dose than with the 1-mg dose. Diurnal rhythms were restored during the post-treatment period. Similarly, treatment with ZK 98.734 (5 mg, n = 8/group) at 1000 h caused a decrease in testosterone and LH levels. The levels were significantly (p less than 0.05) lower at 3 and 6 h after treatment compared to pretreatment levels.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
The first total synthesis of prasinic acid is being reported along with its biological evaluation. The ten step synthesis involved readily available and cheap starting materials and can easily be transposed to large scale manufacturing. The crucial steps of the synthesis included the formation of two different aromatic units (7 and 9) and their coupling reaction. The synthetic prasinic acid exhibited moderate antitumor activity (IC50 4.3–9.1 μM) in different lines of cancer cells.  相似文献   
10.
The liquid membrane phenomenon in angiotensin converting enzyme (ACE) inhibitors namely, captopril and lisinopril has been studied. Hydraulic permeability data have been obtained to demonstrate the existence of the liquid membrane in series with a supporting membrane generated by the ACE inhibitors. Data on the transport of the relevant permeants in presence of the liquid membrane formed by ACE inhibitors indicate that liquid membrane phenomenon is likely to play a significant role in the action of ACE inhibitors.  相似文献   
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