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41.
Campylobacter jejuni 81-176 grown in vivo in rabbit ileal loops expresses novel proteins that are not expressed under standard laboratory culture conditions. A new protein with a molecular mass of ca. 180 kDa is expressed at 14, 24, and 48 h of infection. Three other proteins, with molecular masses of ca. 66, 43, and 35 kDa, are overexpressed during different phases of infection. Expression of these proteins stops immediately during the first passage in laboratory media, and they do not elicit a human immune response. Two other proteins, with molecular masses of ca. 84 and 47 kDa, expressed 48 h after infection can be identified by using convalescent sera from human volunteers who were immune to C. jejuni infection upon rechallenge; these proteins were not visualized on sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels by Coomassie blue staining or silver staining. Antibodies to the 84- and 47-kDa proteins are of the immunoglobulin G class. Both preinfection and convalescent human sera react strongly to the C. jejuni flagellin (a 58-kDa protein), suggesting the presence of cross-reactive antibodies to this protein in healthy humans. Major outer membrane protein and flagella may play a role in providing protection against C. jejuni disease, but our data suggest that there are other proteins expressed only during in vivo growth of the organism that elicit a strong immune response in human C. jejuni infections.  相似文献   
42.
We utilized collagen specific second harmonic generation (SHG) signatures coupled with correlative immunofluorescence imaging techniques to characterize collagen structural isoforms (type I and type III) in a murine model of myocardial infarction (MI). Tissue samples were imaged over a four week period using SHG, transmitted light microscopy and immunofluorescence imaging using fluorescently-labeled collagen antibodies. The post-mortem cardiac tissue imaging using SHG demonstrated a progressive increase in collagen deposition in the left ventricle (LV) post-MI. We were able to monitor structural morphology and LV remodeling parameters in terms of extent of LV dilation, stiffness and fiber dimensions in the infarcted myocardium.  相似文献   
43.
Anemia is a common health problem but control of anemia in pregnant women is less well studied. The purpose was to study prevalence of anemia in young pregnant women, correlate with indices and study significance of identification of hemoglobinopathies. Of the 120 pregnant women, Hb was less than 8 g% in 58 (44.2%). Seventy-eight (65%) had iron deficiency, 22 (18.3%) had dimorphic anemia, and 14 (11.6%) had hemolytic anemia. Megaloblastic anemia was present in 6 (5%). Of hemolytic anemia, 50% were thalassemia trait. MCV< 76 fl was observed in 88 (73.3 %) cases. MCV<76 fl and MCH < 27 pg had 100 % sensitivity and 28.7 % specificity for screening of beta-thalassemia trait. NESTROFT had comparable sensitivity but lower specificity (14.9%). Sixty-three percent (60/78) of IDA had increased RDW whereas 78 % (11/14) of hemolytic anemia had RDW value in normal range (p value< 0.05). MCV/RBC of <14 was more specific parameter (96.8%) for beta-thalassemia trait. Four high-risk couples were identified. Thus, moderate to severe anemia was observed in most pregnant women. Hemoglobinopathies should be screened in antenatal clinics to identify the couples that would need a prenatal test. A lower MCV/RBC with RDWin the normal range may be useful in screening for thalassemia trait in pregnant women.  相似文献   
44.
CpG DNA, liposome and refined antigen oral cholera vaccine   总被引:1,自引:0,他引:1  
An oral cholera vaccine made up of three Vibrio cholerae antigens, i.e. lipopolysaccharide (LPS), recombinant toxin co-regulated pili (rTcpA) and heat-treated cholera toxin (H-CT) has been developed in six different formulations. Eight-week-old Wistar rats were divided into nine groups and immunized as follows: the first group received the oral vaccine 1 consisting of the three antigens (LPS, rTcpA and H-CT) associated with a liposome (L) and bacterial CpG-DNA (ODN#1826). The rats of groups 2 and 3 received oral vaccines 2 and 3 consisting of the liposome-associated three antigens with and without non-bacterial CpG-DNA (ODN#1982), respectively. Rats of groups 4 received oral vaccine 4 consisting of the three antigens mixed with the ODN#1826, similar to vaccine 1, but without liposome. Rats of groups 5 and 6 received oral vaccines 5 and 6 consisting of the three antigens with and without ODN#1982, respectively, similar to vaccines 2 and 3, but without liposome. Rats of groups 7, 8 and 9 received oral placebos, namely liposomes (L), ODN#1826 (CpG), and vaccine diluent, i.e. 5% NaHCO3 solution, respectively. All vaccines were given in three doses at 14-day intervals. It was found that the combination of liposome and ODN#1826 in vaccine 1 evoked the highest immune response to V. cholerae antigen compared to other vaccine formulations and placebos, as measured by the appearance of antigen-specific antibody-producing cells in the intestinal lamina propria. The immunogenicity according to the magnitude of the immune response was: V1>V2=V3>V4>V5=V6>V7=V8=V9. The results of this study indicate that CpG-DNA and liposome are effective mucosal adjuvants for an oral cholera vaccine prepared from refined V. cholerae antigens and their combination seems to be synergistic. The potential role of liposome as a vaccine delivery vehicle has been confirmed.  相似文献   
45.
46.
Mutations in the basal core promoter (BCP) and precore (PC) regions are associated with persistent and intermittently high hepatitis B virus (HBV) replication in several patients. The variability in the functional domains of BCP and PC region of HBV and their association with disease progression and clinical outcome were assessed in Eastern India, an unique region where three HBV genotypes, A, D, and C are prevalent among the same ethnic group. PCR amplification and direct sequencing of BCP and PC region was done on sera obtained from 130 HBsAg positive subjects with different clinical presentations. Associations of the apparent risk factors with clinical advancement were evaluated by statistical methods including multiple logistic regression analyses (MLR). HBV genotype A was present in 33.08%, C in 25.38%, and D in 41.54% cases. Genotypes A and C were associated with higher rate of T1762/A1764 mutations than the most predominant genotype D. HBeAg negative state was associated with considerably higher rate of C1753 mutation. T1762/A1764 along with C1753 was common among cirrhosis and T1762/A1764 without C1753 was frequent among chronic liver disease cases. No significant association was found between A1896 point mutation and clinical status. Multivariate analysis revealed that T1762/A1764 double mutation, HBV/A, age ≥25 years, C1753 and A1899 were critical factors for clinical advancement while age ≥25 years and C1753 as significant predictor for cirrhosis in comparison with chronic liver disease. In conclusion, the analysis of the BCP variability may help in monitoring the progression towards advanced liver disease in Eastern Indian patients.  相似文献   
47.
48.
Panigrahi MK 《Neurosurgery》2002,50(6):1403-4; author reply 1404
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49.
Supercyclone in Orissa: an assessment of psychological status of survivors   总被引:2,自引:0,他引:2  
The study assessed the impact of the Orissa supercyclone on survivors' locus of control, anxiety, depression, and posttraumatic stress. The study was conducted in structured interview sessions 3 months after the supercyclone. The affected people (n = 65) who were close to the epicenter of supercyclone and lost their family members, relatives, and property, experienced more anxiety, depression, and posttraumatic stress than the unaffected (n = 65) who were away from the epicenter of supercyclone and had not experienced any loss. Effects of exposure remained significant with the effects of sex and neuroticism controlled. External support reduced anxiety and depression, and the amount of loss experienced by the survivors significantly increased external locus of control and anxiety.  相似文献   
50.
Non-verbal serial pattern learning in patients with mild brain injury was examined using a serial pattern-learning task introduced by Nissen and her colleagues. The task involves two types of pattern cycles: Simple and Complex. Each pattern cycle consists of eight acquisition trials followed by a final generation phase, i.e. the ninth trial. The subjects responded to the asterisks appearing in repetitions of a 10-element spatial sequence in each pattern cycle. Eighty subjects were taken, of which 40 subjects had mild head injury and 40 were uninjured. Prior research with this task has shown that individuals show intact performance on the indirect measure of pattern learning, but are impaired on the direct measure. The results of this study showed that mild brain injury does cause a marked disruption in the ability to learn and remember serial pattern information in both simple and complex patterns.  相似文献   
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