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1

Bioengineered bugs expressing oligosaccharide receptor mimics  

UK PubMed Central (United Kingdom)

Many microbial pathogens recognize oligosaccharides displayed on the surface of host cells as receptors for toxins and adhesins. These ligand-receptor interactions are critical for disease pathogenesis,...Full Text Available

2010-05-01

2

discs large in the Drosophila testis  

UK PubMed Central (United Kingdom)

Gamete development requires a coordinated soma-germ line interaction that ensures renewal and differentiation of germline and somatic stem cells. The physical contact between the germline and somatic...Full Text Available

2010-10-01

3

Smoking and reproduction: The oviduct as a target of cigarette smoke  

UK PubMed Central (United Kingdom)

The oviduct is an exquisitely designed organ that functions in picking-up ovulated oocytes, transporting gametes in opposite directions to the site of fertilization, providing a suitable environment...Full Text Available

4

Severe teratozoospermia and its influence on pronuclear morphology, embryonic cleavage and compaction  

UK PubMed Central (United Kingdom)

BackgroundFertilization, cell division and embryo development depend on genomic contributions from male and female gametes. We hypothesize that teratozoospermic sperm influences...Full Text Available

5

Bacterial Pili exploit integrin machinery to promote immune activation and efficient blood-brain barrier penetration.  

Science.gov (United States)

Group B Streptococcus (GBS) is the leading cause of meningitis in newborn infants. Bacterial cell surface appendages, known as pili, have been recently described in streptococcal pathogens, including GBS. The pilus tip adhesin, PilA, contributes to GBS adherence to blood-brain barrier (BBB) endothelium; however, the host receptor and the contribution of PilA in central nervous system (CNS) disease pathogenesis are unknown. Here we show that PilA binds collagen, which promotes GBS interaction with the ?(2)?(1) integrin resulting in activation of host chemokine expression and neutrophil recruitment during infection. Mice infected with the PilA-deficient mutant exhibit delayed mortality, a decrease in neutrophil infiltration and bacterial CNS dissemination. We find that PilA-mediated virulence is dependent on neutrophil influx as neutrophil depletion results in a decrease in BBB permeability and GBS-BBB penetration. Our results suggest that the bacterial pilus, ...

2011-09-06

6

Regulation and secretion of Xanthomonas virulence factors  

British Library Electronic Table of Contents (United Kingdom)

Abstract Plant pathogenic bacteria of the genus Xanthomonas cause a variety of diseases in economically important monocotyledonous and dicotyledonous crop plants worldwide. Successful infection and bacterial multiplication in the host tissue often depend on the virulence factors secreted including adhesins, polysaccharides, LPS and degradative enzymes. One of the key pathogenicity factors is the type III secretion system, which injects effector proteins into the host cell cytosol to manipulate plant cellular processes such as basal defense to the benefit of the pathogen. The coordinated expression of bacterial virulence factors is orchestrated by quorum-sensing pathways, multiple two-component systems and transcriptional regulators such as Clp, Zur, FhrR, HrpX and HpaR. Furthermore, virule...

2010-01-01

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Mannose-specific interaction of Lactobacillus plantarum with porcine jejunal epithelium  

British Library Electronic Table of Contents (United Kingdom)

Abstract Host-microorganism interactions in the intestinal tract are complex, and little is known about specific nonpathogenic microbial factors triggering host responses in the gut. In this study, mannose-specific interactions of Lactobacillus plantarum 299v with jejunal epithelium were investigated using an in situ pig Small Intestinal Segment Perfusion model. The effects of L. plantarum 299v wild-type strain were compared with those of two corresponding mutant strains either lacking the gene encoding for the mannose-specific adhesin (msa) or sortase (srtA; responsible for anchoring of cell surface proteins like Msa to the cell wall). A slight enrichment of the wild-type strain associated with the intestinal surface could be observed after 8 h of perfusion when a mixture of wild-type and...

2008-01-01

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Ultrastructure of the spermatozoon of the digenean Cricocephalus albus (Kuhl & van Hasselt, 1822) Looss, 1899 (Platyhelminthes, Pronocephaloidea, Pronocephalidae), parasite of ''the hawksbill sea turtle''Eretmochelys imbricata (Linnaeus, 1766) in Senegal  

British Library Electronic Table of Contents (United Kingdom)

The mature spermatozoon of Cricocephalus albus is filiform, tapered at both ends and shows the following features: 2 axonemes of different lengths presenting the 9+''1'' trepaxonematan pattern, 2 bundles of parallel cortical microtubules, a mitochondrion and a nucleus. Nevertheless, the particularity of the spermatozoon of C. albus is its anterior extremity with an apical electron-dense material associated with extramembranar ornamentation, a cytoplasmic dorsolateral expansion and spine-like bodies. To our knowledge, such an anterior extremity of the spermatozoon has not previously been described from a species of the superfamily Pronocephaloidea. Our study provides new data on the mature gamete of C. albus in order to improve our understanding of the pronocephaloidean phylogenetic relatio...

2011-01-01

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Analysis of Elements in The Baltic Sea Sediment by Using Gamma Spectrometry  

International Nuclear Information System (INIS)

We have done analysis of elements in the Baltic sea sediment by using gamma spectrometry in neutron activation analysis Goal of the analysis is to determine the rate of morsel elements which is contained in the Baltic sea sediment. Sample of the Baltic sea Sediment (IAEA-SED-1), Standard of Reference Material (SRM) 1646 Estuarine Sediment and Standard Ce, Fe, Sc, and Co are put into vial of capsule rabbit, then irradiated together for 30 minutes in rabbit facility Multi Purpose Reactor at power of 25 MW and then cooled for one week. Next sample, standard, and SRM which have irradiated, each is cut for 30 minutes using gamma spectrometer. Result of analysis of rate of elements Ce, Fe, Sc and Co in the baltic sea sediment successively equal to 141.20 ppm, 5.91 %, 14.88 ppm, and 19.59 ppm. Result of analysis in SRM Estuarine sediment successively equal to 96.60 ppm, 3.21 %, 10.25 ppm, and 9.63 ppm. Result of this analysis if compared to the value ...

2007-04-01

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Hemoglobin of mice with radiation-induced mutations at the hemoglobin loci  

International Nuclear Information System (INIS)

Chemical analyses were done on the abnormal hemoglobins of the five (101 x SEC)F_1 offspring of X- irradiated adult SEC mice to determine which hemoglobin genes were expressed in each hemoglobin variant. Three offspring of irradiated SEC males did not express either of the two kinds of #alpha#-chains normally found in all SEC mice. The deficient #alpha#-chain synthesis caused these mice to exhibit an #alpha#-thalassemia similar to human #alpha#-thalassemia. Scanning electron microscopy was used to show that many erythrocytes of mice with #alpha#-thalassemia have bizarre shapes; e.g. many erythrocytes appeared flattened or had thorny projections (acanthocytes). One mutant with a tandem duplication of a segment of chromosome 7 (site of locus determining #beta#-chain structure) produced twice as much SEC as 101 #beta#-chain polypeptides. One mutant that probably arose by non-disjunction of chromosome 7's in its unirradiated 101 mother and loss of chromosome 7 from the ...

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Assisted reproductive technologies for male factor infertility.  

Science.gov (United States)

Experience in the diagnosis and treatment of infertility has led to an increased understanding of the prominent role male factors play in many couples' inability to conceive. While many forms of male factor infertility are amenable to treatment, for some patients there is no corrective therapy available. For this reason, a great deal of attention has been focused on developing technologies for semen processing and sperm utilization in cases of decreased semen quality. One area of research is the development of more sophisticated methods of assessing sperm function, as well as methods of sperm preparation. Progress is also being made in the application of technologies such as intrauterine insemination and in vitro fertilization in the treatment of male factor infertility. Such developments have improved prospects for fertility among patients suffering from decreased semen quality, as well as those suffering from such disorders as ejaculatory failure and congenital vasal agenesis. ...

1991-10-01

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Reproductive Ecology of Yakima River Hatchery and Wild Spring Chinook; Yakima/Klickitat Fisheries Project Monitoring and Evaluation, 2004-2005 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

This report is intended to satisfy two concurrent needs: (1) provide a contract deliverable from Oncorh Consulting to the Washington Department of Fish and Wildlife (WDFW), with emphasis on identification of salient results of value to ongoing Yakima/Klickitat Fisheries Project (YKFP) planning and (2) summarize results of research that have broader scientific relevance. This is the fourth in a series of reports that address reproductive ecological research and monitoring of spring chinook populations in the Yakima River basin. This annual report summarizes data collected between April 1, 2004 and March 31, 2005 and includes analyses of historical baseline data, as well. Supplementation success in the Yakima Klickitat Fishery Project's (YKFP) spring chinook (Oncorhynchus tshawytscha) program is defined as increasing natural production and harvest opportunities, while keeping adverse ecological interactions and genetic impacts within acceptable bounds (Busack et al. 1997). ...

2005-05-01