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41.
The effects of bacterial endotoxin (lipopolysaccharide, LPS) are amplified by lipopolysaccharide binding protein (LBP) and CD14, resulting in cellular activation at very low concentrations of LPS. To investigate the importance of this pathway in acute lung injury, we measured LPS, LBP, and soluble CD14 (sCD14) in the bronchoalveolar lavage fluid (BAL) of 82 patients with acute respiratory distress syndrome (ARDS). LBP and sCD14 increased markedly in BAL of patients with ARDS. sCD14 and LBP each were strongly related to BAL total protein and polymorphonuclear neutrophil (PMN) concentration, whereas LPS concentration was not. Multivariate analyses showed sCD14 to be strongly related to BAL total protein, even after controlling for LPS and LBP concentrations. sCD14 was strongly and independently related to PMN concentration, after controlling for BAL LPS, LBP, and interleukin-8 (IL-8). The BAL LPS concentration was not strongly related to either BAL total protein or BAL PMN. The BAL sCD14 and LBP values were similar in all subgroups of patients with ARDS, and were not related to survival. The serum LBP and sCD14 were elevated in ARDS, but were not related to BAL total protein, LBP, sCD14, PMN, or clinical outcome. Thus, LBP and sCD14 reach high concentrations in the lungs of patients with ARDS, and BAL sCD14 is strongly related to two major indices of lung inflammation: total protein and PMN concentration. CD14-dependent mechanisms may contribute to lung inflammation in ARDS.  相似文献   
42.
PURPOSE: We investigated the association, treatment options and outcomes of patients with ureteropelvic junction obstruction and concomitant vesicoureteral reflux. MATERIALS AND METHODS: We analyzed 6,790 consecutive pediatric urology records at our university. Treatment options included observation, and primary pyeloplasty, ureteroneocystostomy and nephroureterectomy. Hydronephrosis, reflux and obstruction were judged as resolved, improved, unchanged or worse. RESULTS: A total of 1,140 patients had vesicoureteral reflux, 224 had ureteropelvic junction obstruction and 41 had both conditions (39 ipsilateral and 6 contralateral kidneys). There was no increased risk of obstruction in patients with reflux when all grades of reflux were grouped (odds ratio 1.26, confidence interval 0.91 to 1.71). In contrast, subgroup analysis of patients with high grade reflux demonstrated a 5-fold increased risk of obstruction (odds ratio 5.0, confidence interval 2.4 to 10.8). One patient was lost to followup. Observation of 6 kidneys led to resolution of reflux in 3 (50%), resolution of obstruction in 3 (50%) and resolution or improvement of hydronephrosis in 4 (67%). Primary pyeloplasty was done on 29 kidneys with 10 (35%) requiring subsequent ureteroneocystostomy. At latest followup hydronephrosis resolved or improved in 24 patients (83%), vesicoureteral reflux resolved or improved in 19 (66%) and ureteropelvic junction obstruction resolved in all. Primary ureteroneocystostomy was performed on 5 kidneys, all of which required subsequent pyeloplasty. Hydronephrosis resolved in 3 patients (60%), and reflux and obstruction resolved in all. Two patients treated with primary nephroureterectomy, and 1 who underwent concomitant pyeloplasty and ureteroneocystostomy have had no subsequent urological problems. One patient awaits primary pyeloplasty. CONCLUSIONS: High grade vesicoureteral reflux is associated with ureteropelvic junction obstruction. No association with low or intermediate grade reflux was demonstrated. While some patients may be monitored expectantly, in our series pyeloplasty or nephrectomy was required in 81% and ureteroneocystostomy was required in 36%. In no case did primary ureteroneocystostomy protect against the subsequent need for pyeloplasty.  相似文献   
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44.
The choline-containing phosphoglycolipid, MfGL-II, is the major polar lipid of Mycoplasma fermentans PG18. Anti-MfGL-II antisera raised in rabbits using the purified MfGL-II as an immunogen were employed in immunogold electron microscopic and immunofluorescence studies showing that MfGL-II is uniformly distributed and exposed on the cell surface of M. fermentans cells. The specificity of the antibodies was determined by immunostaining of lipid extracts separated by thin layer chromatography. The antibodies recognize lipids specific to M. fermentans but did not cross-react with lipid extracts of M. penetrans, M. capricolum, M. gallisepticum or Acholeplasma laidlawii. As phosphocholine almost completely abolished antibody interaction with MfGL-II in an ELISA assay it is suggested that the anti-MfGL-II repertoire is composed primarily of anti-phosphocholine antibodies. The anti-MfGL-II antisera inhibit the attachment of M. fermentans to Molt-3 lymphocytes suggesting that MfGL-II plays a major role in M. fermentans-host cell interaction.  相似文献   
45.
Bet v 1, the single major allergen from birch pollen, shares IgE epitopes with all major tree pollen allergens from closely related species such as alder, hazel, hornbeam, beech, and European chestnut. Because of high sequence homologies among these allergens and the well-studied cross-reactivities on B cell epitopes, Bet v 1 is a representative model protein which can be used for in vitro studies. The cDNA coding for Bet v 1, the single major allergen from birch pollen, was cloned into the T7-based Escherichia coli expression system pMW 175/BL21(DE3) and synthesized as a nonfusion protein. In contrast to other E. coli systems (e.g., pKK233-2/JM105), this system produces high levels of readily extractable proteins corresponding to 5-10% of E. coli total protein, the percentage varying with culture conditions. The overall yield was 8-10 mg of purified recombinant protein per liter of culture medium. The recombinant allergen was purified by several steps, including ion-exchange and hydrophobic interaction chromatography. The purified recombinant allergen showed identical immunological properties with the respective natural counterpart. The use of recombinant allergens of high purity is expected to result in more accurate diagnostic procedures, but possibly also in a superior immunotherapy of Type I allergic diseases when compared with methods using crude allergen extracts containing various amounts of allergen concentrations.  相似文献   
46.
The numbers of argyrophilic nucleolar organizer regions (AgNORs) were quantified in oral carcinomas (n = 39) with or without human papillomavirus (HPV) infection. The AgNOR counts of the HPV-positive samples (7.15 +/- 2.13) were not significantly (P = 0.09) higher than those of the HPV-negative ones (6.16 +/- 1.89). Furthermore, the lesions infected with multiple HPV types had greater counts than those with HPV type 16/18 infection alone. Significant differences were observed between the mean counts of the poorly (10.50 +/- 0.54), moderately (7.31 +/- 1.07) and well- (5.12 +/- 0.85) differentiated carcinomas. The mean AgNOR numbers in the oral carcinomas at TNM stages III/IV were found to be significantly (P < 0.01) higher than the numbers in corresponding stage II lesions. Cytokinetics of the lesions assessed by the bromodeoxyuridine (Brdu) labelling index (LI%) showed a linear correlation (r = 0.91; P < 0.0001) with their respective mean AgNOR counts.  相似文献   
47.
Antisera made against whole cells of Bordetella avium protected turkeys against disease signs of turkey coryza, but antiserum against the dermonecrotic heat-labile toxin (DHLT) did not. Neither antiserum against whole cells nor antiserum against DHLT protected turkeys against colonization of the trachea by B. avium. At least 25 bands in whole cell lysate of B. avium separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) reacted in immunoblots with protective antiserum. These bands occurred at < 40 kDa and > 105.3 kDa. DHLT had an isoelectric point (pI) in the range pH 6.3-6.7. Following SDS-PAGE of isoelectric-focused fractions, two bands were recognized by anti-DHLT with immunoblots of pI 6.3, pI 6.5, and pI 6.7 fractions separated by SDS-PAGE.  相似文献   
48.
BACKGROUND: In response to the increasing rate of skin cancer, particularly melanoma in the United States, the Environmental Protection Agency, the National Weather Service, the Centers for Disease Control and Prevention, National Association of Physicians for the Environment, and the American Academy of Dermatology, developed the Ultraviolet Index (UVI) to inform the public of the strength of the sun's rays and advise on methods for sun protection. OBJECTIVE: Our purpose was to evaluate the extent to which television stations and newspapers reported the UVI and assess the public's response to it. METHODS: To evaluate the effect of this effort, we surveyed television weather forecasters at 185 stations and examined weather pages in 54 newspapers in 58 cities that received the UVI reports. We also conducted a population probability telephone survey of 700 white adults (18 years of age and older) in these 58 cities. RESULTS: Seventy-one percent of the 169 stations that provided survey data for both 1994 and 1995 broadcast the UVI; 61% of newspapers reported the UVI. Nearly 64% of the 700 respondents (n = 445) had heard of the UVI. Of these respondents, 38% (n = 170) stated that they or their family changed their sun protection practices as a result of the UVI. CONCLUSION: The majority of television weather forecasters and newspapers reported the UVI. Most of the public was aware of the UVI, causing some to change sun protection practices. Further evaluation is required to maximize the effect of the UVI on sun protection practices.  相似文献   
49.
Tardive dyskinesia is an involuntary movement disorder developing following treatment with neuroleptics. As many as 50% of chronic psychotic patients develop this disabling condition. No treatment has been found effective for tardive dyskinesia. This study was undertaken to meta-analyze the effects of vitamin E (alpha-tocopherol) reported in the last decade. All studies published since 1987, focusing on vitamin E and tardive dyskinesia are reviewed. Double-blind studies are analyzed using measures of effect and variance as described by secondary analysis of magnitude of effects in pooled data. A total of 223 patients received vitamin E treatment (400-1600 IU/day) for tardive dyskinesia, in 12 studies. A significant subgroup (28.3%) showed a modest improvement. Vitamin E was well tolerated, and only rarely did side effects occur-of no clinical significance. Vitamin E is a safe, well-tolerated compound that may provide some beneficial effects in patients suffering from neuroleptic-induced tardive dyskinesia.  相似文献   
50.
The trafficking of GLUT4, a facilitative glucose transporter, is examined in transfected CHO cells. In previous work, we expressed GLUT4 in neuroendocrine cells and fibroblasts and found that it was targeted to a population of small vesicles slightly larger than synaptic vesicles (Herman, G.A, F. Bonzelius, A.M. Cieutat, and R.B. Kelly. 1994. Proc. Natl. Acad. Sci. USA. 91: 12750-12754.). In this study, we demonstrate that at 37 degrees C, GLUT4-containing small vesicles (GSVs) are detected after cell surface radiolabeling of GLUT4 whereas uptake of radioiodinated human transferrin does not show appreciable accumulation within these small vesicles. Immunofluorescence microscopy experiments show that at 37 degrees C, cell surface-labeled GLUT4 as well as transferrin is internalized into peripheral and perinuclear structures. At 15 degrees C, endocytosis of GLUT4 continues to occur at a slowed rate, but whereas fluorescently labeled GLUT4 is seen to accumulate within large peripheral endosomes, no perinuclear structures are labeled, and no radiolabeled GSVs are detectable. Shifting cells to 37 degrees C after accumulating labeled GLUT4 at 15 degrees C results in the reappearance of GLUT4 in perinuclear structures and GSV reformation. Cytosol acidification or treatment with hypertonic media containing sucrose prevents the exit of GLUT4 from peripheral endosomes as well as GSV formation, suggesting that coat proteins may be involved in the endocytic trafficking of GLUT4. In contrast, at 15 degrees C, transferrin continues to traffic to perinuclear structures and overall labels structures similar in distribution to those observed at 37 degrees C. Furthermore, treatment with hypertonic media has no apparent effect on transferrin trafficking from peripheral endosomes. Double-labeling experiments after the internalization of both transferrin and surface-labeled GLUT4 show that GLUT4 accumulates within peripheral compartments that exclude the transferrin receptor (TfR) at both 15 degrees and 37 degrees C. Thus, GLUT4 is sorted differently from the transferrin receptor as evidenced by the targeting of each protein to distinct early endosomal compartments and by the formation of GSVs. These results suggest that the sorting of GLUT4 from TfR may occur primarily at the level of the plasma membrane into distinct endosomes and that the organization of the endocytic system in CHO cells more closely resembles that of neuroendocrine cells than previously appreciated.  相似文献   
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