Publications by authors named "Merrell B"

Claudins are tight junctional proteins implicated in cell polarity and epithelial barrier maintenance. Claudin misregulation adversely impacts developmental aspects of cell differentiation and proliferation. The current research evaluated transcriptional expression for Claudins 1-11 and 18 in the developing murine lung at embryonic days (E) 14.

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It has long been understood that increased epithelial permeability contributes to inflammation observed in many respiratory diseases. Recently, evidence has revealed that environmental exposure to noxious material such as cigarette smoke reduces tight junction barrier integrity, thus enhancing inflammatory conditions. Claudin-6 (Cldn6) is a tetraspanin transmembrane protein found within the tight junctional complex and is implicated in maintaining lung epithelial barriers.

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This paper describes an investigation of the use of computer tomography (CT) to genetically improve carcass composition and conformation in Scottish Blackface sheep. After 5 years of selection on an index designed to improve both composition and conformation (the 'CT index'), a large response was observed in the CT index, with genetic progress equivalent to 0.11 phenotypic standard deviations per year.

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Multiple ovulation and embryo transfer (MOET) has the potential to increase the rate of genetic improvement in sheep. However, better realization of this potential requires maximum survival rates of transferred embryos of high genetic merit after transfer into recipient ewes. These studies were therefore conducted to investigate the effect of both embryonic and recipient ewe factors on the survival rate of transferred embryos.

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Multiple ovulation and embryo transfer (MOET) has the potential to increase the rates of genetic improvement in sheep. However, better realization of this potential requires a higher yield of transferable embryos. Thus we investigated some factors that may contribute to high embryo yield and quality under field conditions, as part of an ongoing MOET program.

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Two different regimens of praziquantel, 40 mg/kg in a single dose and 60 mg/kg in two divided doses administered 6 hr apart, for the treatment of Schistosoma mansoni infection were compared in Abu Homos, Egypt. Participants in this study included 1,588 subjects of both sexes between five and 50 years old from two rural communities; 730 from Farshout and 858 from Om El-Laban. The prevalence of S.

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Somali refugees living in a camp located in Djibouti were studied in October 1991 and May 1992. The refugees had been living at the camp for about two years. The median age of volunteers was 25 years, of whom 69% were female.

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Objectives: The purpose of this study was to determine whether respiratory disease due to crowded living conditions and high levels of suspended and blowing sand had a major adverse impact on US military personnel during Operation Desert Shield.

Methods: A questionnaire survey was administered to 2598 combat troops stationed in Northeast Saudi Arabia for a mean of 102 days. Samples of surface sand from seven different locations were analyzed by scanning electron microscopy and x-ray diffraction.

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Background: Under combat conditions infectious disease can become a major threat to military forces. During Operation Desert Shield, there were numerous outbreaks of diarrhea among the U.S.

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Fourteen of 3,754 U.S. Marines who participated in a joint United States-Republic of Korea training exercise during the autumn of 1986 developed hemorrhagic fever with renal syndrome (HFRS).

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The incidence and etiology of travelers' diarrhea was studied in a crew of 1,914 sailors and marines aboard a U.S. Navy ship during a western Pacific deployment.

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Antibody levels against antigens from eight oral micro-organisms were measured in sera and gingival tissue extracts from adult periodontitis patients and healthy subjects by an enzyme-linked immunosorbent assay. The antibody levels of diseased serum samples were significantly higher than those of healthy serum samples. Analysis of diseased sera indicated that antibody levels against Bacteriodes gingivalis antigens were significantly higher than antibody levels against all the other antigens tested except for those from B.

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The rapid detection of Bacteroides gingivalis by immunological methods using monoclonal antibodies could greatly improve the diagnosis and prognosis of severe periodontal disease in adults. In this study, three distinct hybridomas were produced which secrete monoclonal antibodies to soluble and whole-cell antigen preparations of B. gingivalis.

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The initial interaction and adherence of Vibrio parahemolyticus to epithelial tissue culture cells, human buccal epithelial cells, and the ileal mucosa of mice were studied. Using scanning electron microscopy, adherent bacteria were observed only on degenerating human embryonic intestinal, HeLa, and buccal cells; healthy normal cells were devoid of bacteria. Sheared V.

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Aeromonas species were recovered from over 27% of 183 chlorinated drinking water samples collected during an 18-month period. Sixteen of 20 isolates tested elicited a cytotoxic response by Y-1 mouse adrenal cells. None of the strains was either enterotoxigenic by the rabbit ligated ileal loop assay, exhibited piliation, or showed significant mannose resistant adherence to human buccal cells.

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Bone resorption (gangrenous stomatitis) was found to be associated with extensive bacterial colonization of mandibular bone in three separate cases of noma. Light and electron microscopy revealed a heterogeneous bacterial population with a long, filamentous, Gram-positive organism predominantly in direct contact with the resorbing bone front. The bone was completely denuded and no osteoclastic activity was observed.

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Fifteen Aeromonas isolates from various human infections and nine isolates from polluted water were identified as either Aeromonas hydrophila or Aeromonas sobria and examined for cytotoxigenicity, enterotoxigenicity, adherence to epithelial cells, and other virulence-associated factors, including proteases, lipases, elastases, and hemolysins. Two groups of organisms (I and II) were distinguishable based on differences in median lethal doses in mice and cytotoxicity for Y-1 adrenal cells. Group I clinical and environmental strains had median lethal doses of less than 10(7) colony-forming units, were cytotoxic, frequently possessed several virulence-associated factors, and had lysine decarboxylase-positive or Voges-Proskauer-positive phenotypes or both.

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Campylobacter fetus ss. jejuni has recently been recognized as a frequent enteric pathogen of man. Although long known as a significant pathogen of domestic animals, little is known regarding mechanisms of colonization and pathogenesis.

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