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81.
Two-dimensional gel electrophoresis and immunoblotting of Campylobacter pylori proteins. 总被引:10,自引:5,他引:10 下载免费PDF全文
Whole-cell, outer-membrane protein, flagellum-associated antigens and partially purified urease of Campylobacter pylori were analyzed by two-dimensional gel electrophoresis. C. pylori strains were readily distinguished from strains of Campylobacter jejuni, C. coli, and C. fetus by absence of major outer membrane proteins with Mrs of 41,000 to 45,000. C. pylori strains also lacked the acidic surface-array proteins at Mr 100,000 to 149,000 identified previously in serum-resistant strains of C. fetus. Surface labeling of intact C. pylori cells with 125I revealed two common major proteins, which we have designated protein 2 (pI 5.6 to 5.8, Mr 66,000) and protein 3 (pI 5.2 to 5.5, Mr 63,000). Proteins 2 and 3 were also the major components (subunits) observed in partially purified urease. Partially purified preparations of flagella consistently contained proteins 2 and 3. Thus, urease appears to be associated with both outer membranes and flagella of C. pylori. C. pylori strains also possessed an antigen at Mr 59,000 which was cross-reactive with antiserum against flagella of C. jejuni. However, the antigen did not appear to be associated with flagella per se in C. pylori. Protein 2 was unique to C. pylori among the Campylobacter species studied. It was not recognized by antibody against whole cells of C. jejuni or C. fetus or flagella of C. jejuni. Protein 3 was cross-reactive with antiserum against whole cells of C. jejuni and C. fetus, as were several other major protein antigens. Because protein 2 is a major outer membrane protein that is apparently unique to C. pylori, development of monospecific antibodies against this antigen may be useful for the identification of C. pylori in tissues, and purified antigen may be useful for serologic tests for specific diagnosis of C. pylori infections. 相似文献
82.
The mechanical properties of anterior cruciate ligament (ACL) reconstruction scaffolds were evaluated after exposure to functional challenges in vitro: cyclic loading combined with various proteolytic enzymes. Scaffolds were prepared from collagen fibers that were uncrosslinked (UNXL), crosslinked with ultraviolet irradiation (UV), or 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC; 10 or 25 mM). Structural properties of scaffolds were determined following 1-h exposure to saline, trypsin, or bacterial collagenase, with and without simultaneous cyclic tensile loading (0 to 50 g; 0.5 Hz) in vitro. The breaking load and stiffness of UNXL and UV crosslinked scaffolds were significantly reduced by exposure to either trypsin or collagenase. Cyclic loads interacted synergistically with enzymes, rendering UNXL scaffolds untestable and further decreasing the breaking load of UV crosslinked scaffolds by approximately 35%. In contrast, the breaking load and stiffness of EDC crosslinked scaffolds, which were greater than those of UNXL or UV crosslinked scaffolds, were virtually unaffected by the same load and enzyme treatments. These results suggest that EDC is more effective than UV for crosslinking and stabilizing load-bearing collagen fiber ACL reconstruction scaffolds. Application of cyclic loads and enzymes may lead to development of physiologically relevant in vitro test methods for load-bearing scaffolds. 相似文献
83.
Serotypic and genotypic characterization of human serotype 10 rotaviruses from asymptomatic neonates. 总被引:2,自引:7,他引:2 下载免费PDF全文
S J Dunn H B Greenberg R L Ward O Nakagomi J W Burns P T Vo K A Pax M Das K Gowda C D Rao 《Journal of clinical microbiology》1993,31(1):165-169
Human rotaviruses were isolated from asymptomatic neonates at various hospitals and clinics in the city of Bangalore, India, and were found to be subgroup I specific and possess long RNA patterns (M. Sukumaran, K. Gowda, P. P. Maiya, T. P. Srinivas, M. S. Kumar, S. Aijaz, R. R. Reddy, L. Padilla, H. B. Greenberg, and C. D. Rao, Arch. Virol. 126:239-251, 1992). Three of these strains were adapted to tissue culture and found by serotype analysis and neutralization assays to be of serotype 10, a serotype commonly found in cattle but infrequently found in humans and not previously identified in neonates. By RNA-RNA hybridization, a high level of relatedness to a serotype 10 bovine rotavirus strain and a low-to-medium level of relatedness to a human rotavirus strain were observed. Since this human isolate shares a genogroup with bovine rotavirus, it is likely that it originated by interspecies transmission. A human rotavirus strain isolated from asymptomatic neonates and similar to bovine rotavirus might represent a good vaccine candidate. 相似文献
84.
Exfoliated mucosal cells were collected from the oral cavityof three groups at high risk for oral cancer: Indian betel nutchewers, Filipino inverted smokers (burning end of cigar inmouth) and Indian Khaini tobacco chewers. DNA was extractedfrom these samples, as well as from samples of exfoliated cellsof Canadian non-smoking controls. DNA was analyzed for the presenceof aromatic DNA adducts using 32P-postlabel-ling analysis. Fivechromatographically distinct adducts were found in samples fromboth the high risk groups and the nonsmoking controls. Individualadducts were detectable in 3095% of samples, dependingon the adduct and population group. Estimated levels of specificadducts ranged from non-detectable (prevalence relative to normalnucleotides < 1 x 10-9) to occasionally > 1x 10-7. Noadducts were found in high risk groups which did not also appearin control subjects. 相似文献
85.
Dunn Jennifer A. Hackney Jonathan J. Martin Rachelle A. Tietjens Donna Young Timothy Bourke John A. Snell Deborah L. Nunnerley Joanne L. Hall Andrew Derrett Sarah 《Journal of occupational rehabilitation》2021,31(4):730-743
Journal of Occupational Rehabilitation - Purpose Little is currently known about how early intervention vocational rehabilitation (EIVR) works for people with newly acquired neurological conditions... 相似文献
86.
Hannah R. Meredith Emerson Arehart Kyra H. Grantz Alexander Beams Theresa Sheets Richard Nelson Yue Zhang Russell G. Vinik Darryl Barfuss Jacob C. Pettit Keegan McCaffrey Angela C. Dunn Michael Good Shannon Frattaroli Matthew H. Samore Justin Lessler Elizabeth C. Lee Lindsay T. Keegan 《Emerging infectious diseases》2021,27(5):1259
The coronavirus disease pandemic has highlighted the key role epidemiologic models play in supporting public health decision-making. In particular, these models provide estimates of outbreak potential when data are scarce and decision-making is critical and urgent. We document the integrated modeling response used in the US state of Utah early in the coronavirus disease pandemic, which brought together a diverse set of technical experts and public health and healthcare officials and led to an evidence-based response to the pandemic. We describe how we adapted a standard epidemiologic model; harmonized the outputs across modeling groups; and maintained a constant dialogue with policymakers at multiple levels of government to produce timely, evidence-based, and coordinated public health recommendations and interventions during the first wave of the pandemic. This framework continues to support the state’s response to ongoing outbreaks and can be applied in other settings to address unique public health challenges. 相似文献
87.
88.
Modupeola Diyaolu Anne-Laure Thomas Lauren SY Wood Jordan Taylor James CY Dunn 《Journal of pediatric surgery》2021,56(1):5-10
BackgroundShort gut syndrome, a condition characterized by inadequate absorption of nutrients owing to decreased bowel length, has minimal avenues for treatment. We have proposed spring-mediated distraction enterogenesis to lengthen bowel in porcine jejunum as a treatment for short gut. We aim to evaluate the extent of mesenteric neovascularization in segments of lengthened bowel via spring-mediated enterogenesis.MethodsFemale juvenile Yucatan pigs underwent laparotomy and insertion of gelatin-encapsulated compressed nitinol springs, held in place with plication sutures, into the jejunum. At surgery and sacrifice, macroscopic mesenteric blood vessels were counted between the plication sites. Histologic samples of the mesentery were obtained to evaluate microscopic vasculature.ResultsA statistically significant increase in macroscopic mesenteric blood vessels was seen after intestinal lengthening (before: 1.9 ± 0.7 vessels, after: 4.7 ± 1.2 vessels, p = 0.001). A statistical significance is also seen in the density of arterioles (control: 3.0 ± 3.0 vessels/mm, spring: 7.0 ± 9.0 vessels/mm, p = 0.01) and venules (control: 4.0 ± 3.0 vessels/mm, spring: 8.0 ± 8.0 vessels/mm, p = 0.003).ConclusionIntestinal segments lengthened by intraluminal springs demonstrated total greater number of macroscopic vessels and microscopic blood vessels per length of mesentery as compared to control. This suggests local changes within the mesentery to recruit blood supply to growing intestine.Level of evidenceN/AType of studyTreatment study. 相似文献
89.
Lauren SY Wood Hadi S Hosseini Modupeola Diyaolu Anne-Laure Thomas Jordan S Taylor James CY Dunn 《Journal of pediatric surgery》2021,56(7):1192-1198
Introductionshort bowel syndrome is marked by inadequate intestinal surface area to absorb nutrients. Current treatments are focused on medical management and surgical reconfiguration of the dilated intestine. We propose the use of spring-mediated distraction enterogenesis as a novel intervention to increase intestinal length. Given our previous success lengthening intestinal segments using springs with spring constant ~7 N/m that exerts 0.46 N or higher, we sought to determine the minimal force needed to lengthen porcine small intestinal segments, and to explore effects on intestine over time.MethodsJuvenile Yucatan pigs underwent laparotomy with enterotomy to introduce nitinol springs intraluminally (n = 21 springs). Bowel segments (control, spring-distracted) were retrieved on post-operative day (POD) 7 and 14, and lengths measured. Thickness of cross-sectional intestinal layers were measured using H&E, and submucosal collagen fiber orientation measured using trichrome stained sections.Resultsall pigs survived to POD7 and 14. Spring constants of at least 2 N/m exerting a minimum force of 0.10 N significantly lengthened intestinal segments (p <0.0001). The stronger the spring force, the greater the induced thickness of various intestinal layers at POD7 and 14. Collagen fiber orientation was also more disordered because of stronger springs.Conclusiona spring constant of approximately 2 N/m exerting 0.10 N and greater significantly lengthens intestinal segments and stimulates intestinal structural changes at POD7 and 14. This suggests a decreased force is capable of inducing spring-mediated distraction enterogenesis. 相似文献