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991.
Immunoglobulin G antibody response to infection with coccoid forms of Helicobacter pylori 总被引:1,自引:0,他引:1
Figueroa G Faúndez G Troncoso M Navarrete P Toledo MS 《Clinical and diagnostic laboratory immunology》2002,9(5):1067-1071
An increasing number of studies support a potential role for coccoid forms in Helicobacter pylori infection. Evidence for this was obtained through scanning microscopy, genetic analysis for virulence traits, examination of the presence and activity of key enzymes, and other methods. We studied the serum immunoglobulin G responses to coccoid H. pylori forms by enzyme-linked immunosorbent assay (ELISA) and immunoblotting and compared them with those of bacillary cells. Sera from a total of 295 infected individuals were studied; these included sera from 100 patients with duodenal ulcers, 98 patients with nonulcer dyspepsia, 11 patients with gastroduodenal cancer, and 86 asymptomatic individuals. Initially, we characterized and selected coccoid and bacillary antigenic preparations by one-dimensional (1-D) and 2-D gel electrophoresis and immunoblotting. Data showed that coccoid and bacillary preparations with comparable protein contents have similar patterns in 1-D and 2-D electrophoresis gels and antigenic recognition at blotting. These results revealed that coccoid and spiral antigens in ELISA can equally recognize specific antibodies to H. pylori in sera from infected individuals. The analysis of the spiral and coccoid preparations by Western blotting showed no major differences in antigen recognition. No specific bands or profiles associated with a single gastric condition were identified. 相似文献
992.
PURPOSE: To describe the clinical manifestations of multifocal choroiditis presumed to be secondary to allogenic bone marrow transplantation after development of self-tolerance to chronic graft-versus-host disease (GVHD). METHODS: Case report. A 17-year-old male who received an allogenic bone marrow transplant (BMT) from his HLA-identical sister. RESULTS: One year after BMT, grade II chronic GVHD developed. Two years later, vision deteriorated to 20/50 R.E. and 20/400 L.E. Ophthalmoscopic examination showed multiple chorioretinal punched-out scars throughout the posterior pole and mid-periphery of both eyes. Fluorescein angiography showed four choroidal neovascular membranes (CNVMs) in the right eye that were surgically removed, and a subfoveal disciform scar in the left eye. CONCLUSIONS: Multifocal choroiditis is a possible complication related to allogenic BMT. It should be included as a late cause of BMT-associated choroidopathy. Surgical removal of vision-threatening CNVMs is a reasonable approach. 相似文献
993.
Evaluation of two strategies for nutritional education using radio programs in Guadalajara,Mexico 总被引:1,自引:0,他引:1
Cabrera-Pivaral CE Ninel Mayari CL Arredondo Trueba JM Gonzalez Perez GJ Vega Lopez MG Valadez Figueroa I Aldrete Rodriguez MG 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2002,18(5):1289-1294
Modifying knowledge and attitudes through persuasive communication in health via radio has produced encouraging results for public health planners. This study's objective was to measure the effect of an educational strategy on knowledge and attitudes towards nutrition in two marginalized communities in Guadalajara, Mexico. Two communities were randomly selected. In each community a group of individuals was invited to be exposed to radio broadcasts. Using a coded and structured instrument, knowledge and attitudes towards the contents of nutritional education for health were measured before and after the intervention in both groups. Group A (n = 37) was organized and exposed to the dynamics of the radio forum throughout the 4 months during which the project lasted. Group B (n = 33) was not organized, and listened to the radio program according to its own cultural dynamics. Median knowledge and attitudes (KA) for group A was 56.8 in the pre-test and 74.1 in the post-test (W: p = -0.05). In group B the KA results were 53.0 and 59.2, respectively (W: p = -0.05). The results emphasize the advantages of the radio forum as a health communications strategy for human nutrition. 相似文献
994.
995.
Figueroa CD Stuardo M Gonzalez CB Nualart F Corthorn J Bhoola KD Bhoola KD 《Immunopharmacology》1999,43(2-3):211-217
Human neutrophils play a pivotal role in acute inflammation including the regulation of vascular permeability. We have examined the capacity of neutrophil enzymes to hydrolyse human kininogens in vitro and have also explored the potentiality of bradykinin to induce chemotactic migration on neutrophils isolated from peripheral blood. Isolated neutrophils were stimulated with either f-Met-Leu-Phe, thrombin or silica particles coated with human IgG. Neutrophil enzymes obtained by degranulation produced, after 45 min of incubation with high and low molecular weight kininogens, the complete transformation of both proteins in polypeptides ranging from 20 to less than 10 kDa in molecular mass. Supernatants obtained from nonstimulated neutrophils did not modify the molecular size of kininogens. The assay used to test the chemoattractant capacity of synthetic bradykinin on human neutrophils showed that this peptide has no chemotactic activity on cells isolated from healthy subjects. Our results show that stimulation of human neutrophils with opsonized silica, thrombin and the chemotactic peptide f-Met-Leu-Phe induces release of kininogen-hydrolyzing enzymes from these cells. 相似文献
996.
Procalcitonin and C-reactive protein levels in neonatal infections 总被引:17,自引:0,他引:17
G Monneret JM Labaune C Isaac F Bienvenu G Putet J Bienvenu 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(2):209-212
In order to assess the potential of procalcitonin measurement in the management of neonatal sepsis, daily variations in serum procalcitonin (measured by an immunoluminometric assay) were evaluated in 94 control and infected newborn infants in comparison to C-reactive protein (measured by an immunonephelometric method). High levels of procalcitonin correlated with bacterial invasion and showed no discrepancies with C-reactive protein. Procalcitonin increased (up to 400 μg 1-1 ) and returned to the normal range (< 0.1 g1-1 ) more quickly than C-reactive protein, suggesting that procalcitonin may be an early marker of favourable outcome. Another finding is a significant procalcitonin peak on the first day of life in the control group, independent of any infectious stimulus. In conclusion, procalcitonin seems to be an interesting marker of neonatal sepsis but additional investigations are needed to understand better its mechanism of synthesis in order to determine its clinical usefulness. 相似文献
997.
ML Harries JM Walker DM Williams S Hawkins IA Hughes 《Archives of disease in childhood》1997,77(5):445-447
The changes in the male voice in relation to the biological characteristics of puberty were assessed longitudinally in 26 boys. Speaking and singing fundamental frequencies were analysed in relation to the Tanner staging of puberty, saliva testosterone levels, and the Cooksey classification of voice analysis. There were abrupt changes in voice characteristics between Tanner stages G3 and G4 and more gradually from stages C3 to C5 of Cooksey. Although testosterone concentrations were not predictive of the changes, there was a correlation with testis volume. Voice fundamental frequencies were seen to change abruptly in late puberty, in contrast with previous studies. There is a good correlation between the Tanner and Cooksey methods of classification during male puberty. 相似文献
998.
M Shrinath JH Walter M Haeney JM Couriel MA Lewis AL Herrick 《Archives of disease in childhood》1997,76(5):441-444
The case is reported of an infant with hyperammonaemia secondary to severe distal renal tubular acidosis. A clinical association between increased concentrations of ammonia in serum and renal tubular acidosis has not previously been described. In response to acidosis the infant's kidneys presumably increased ammonia synthesis but did not excrete ammonia, resulting in hyperammonaemia. The patient showed poor feeding, frequent vomiting, and failure to thrive, but did not have an inborn error of metabolism. This case report should alert doctors to consider renal tubular acidosis in the differential diagnosis of severely ill infants with metabolic acidosis and hyperammonaemia. 相似文献
999.
OBJECTIVES: To identify problems in managing asthmatic children in school, which if dealt with would help reduce absenteeism and improve participation in school activities. DESIGN: A survey by questionnaire to headteachers. SETTING: Schools in Merthyr and Rhondda Cynon Taff, South Wales. SUBJECT: Asthmatic schoolchildren in areas studied. MAIN OUTCOME MEASURES: Facilities in schools to manage asthma, headteachers' perceptions of knowledge of asthma management by teachers, possession of written policies, and desire for further training. RESULTS: There are 216 schools in the area studied, with 55,166 schoolchildren. A total of 191 (88%) headteachers returned the completed questionnaire. Five hundred and twenty seven (17%) children were reported absent from school during one term because of asthma, with an average of nine days of schooling lost per asthmatic child per term (range 2-16 days). Only 76 (40%) schools allowed children to be responsible for their inhalers, and 12 (6%) schools required parents to administer inhalers. In 115 (60%) schools, headteachers believed their staff were familiar with the management of asthma. A total of 174 (91%) headteachers expressed interest in further training. CONCLUSION: This study highlights the need to train teachers and provide an agreed joint education and health policy on managing asthma in school. 相似文献
1000.
JM Davis WN Rosenfeld SE Richter MR Parad IH Gewolb AR Spitzer WA Carlo RJ Couser A Price E Flaster N Kassem L Edwards J Tierney S Horowitz 《Pediatrics》1997,100(1):24-30
OBJECTIVES: To examine the safety and pharmacokinetics of multiple intratracheal (IT) doses of recombinant human CuZn superoxide dismutase (rhSOD) in premature infants with respiratory distress syndrome who are at risk for developing bronchopulmonary dysplasia (BPD). Methods. Thirty-three infants (700 to 1300 g) were randomized and blindly received saline, 2.5 mg/kg or 5 mg/kg rhSOD IT within 2 hours of surfactant administration. Infants were treated every 48 hours (as long as endotracheal intubation was required) up to 7 doses. Serial blood and urine studies, chest radiographs, neurosonograms, SOD concentration and activity measurements, and tracheal aspirate (TA) inflammatory markers were assessed throughout the 28-day study. RESULTS: SOD concentrations in serum (0.1 [0.05/0.15] microg/mL-geometric mean with lower/upper confidence intervals), tracheal aspirates (TA) (0.2 [0.1/0.3] microg/mL) and urine (0.3 [0.2/0.4] microg/mL) were similar at baseline in all 3 groups and did not change significantly in the placebo group. In the rhSOD treatment groups, SOD concentrations were increased on day 3 and did not change significantly thereafter over the 14-day dosing period (also measured on days 5, 7, and 13). SOD concentrations averaged 0.4 [0.3/0.5] microg/mL in serum, 0.8 [0.6/1.2] microg/mL in TA and 1.1 [1.0/1.3] microg/mL in urine for the low-dose group and 0.6 [0.5/0.7] microg/mL in serum, 1.1 [0.9/1.5] microg/mL in TA, and 2.2 [1.6/2.9] microg/mL in urine for the high-dose group over the 14-day dosing period. Enzyme activity directly correlated with SOD concentration and rhSOD was active even when excreted in urine. TA markers of acute lung injury (neutrophil chemotactic activity, albumin concentration) were lower in the rhSOD agroups compared with placebo. No significant differences in any clinical outcome variable were noted between groups. CONCLUSIONS: These data indicate that multiple IT doses of rhSOD increase the concentration and activity of the enzyme in serum, TA and urine, reduce TA lung injury markers and are well-tolerated. Further clinical trials examining the efficacy of rhSOD in the prevention of BPD are warranted. 相似文献