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11.
J C Morrison W E Roberts K G Perry A S Hume C A Purser 《American journal of perinatology》1992,9(5-6):452-455
The use of gas-liquid chromatography to detect short-chain organic acids in the amniotic fluid of patients with amnionitis has been previously described. Most of the studies describe patients in the early third trimester with such infections. The purpose of the current study was to confirm the correlation of infection with increased production of organic acids and to assess the effect of gestational age on the presence of these short-chain fatty acids in the amniotic fluid. Six patients with confirmed chorioamnionitis were used as positive control subjects. Seventy-two patients at various gestational ages from 18 to 42 weeks with negative Gram's stain and culture results from the amniotic fluid were used as negative control subjects. The data revealed an increased production of organic acids, particularly pyruvic, oxalic and succinic, in patients with amnionitis regardless of gestational age. Interestingly, patients with noninfected amniotic fluid also revealed an increase in the concentrations of volatile organic acids between 27 and 32 weeks' gestation. It appears from this study that previous results correlating chorioamnionitis with an increased production of organic acids in the amniotic fluid may have been confounded by gestational age. 相似文献
12.
13.
The adhesion to hydrogel contact lenses and growth of Serratia marcescens on artificial tear fluid (ATF) soaked lenses was investigated. Results indicated that a corneal ulcer isolate adhered more avidly to lenses; ATF increased adhesion for all strains tested. The contact lens induced acute red eye (CLARE) isolate adhered poorly; however; it grew to a larger extent on ATF-coated lenses. The ability of the corneal ulcer isolate to adhere to lenses may be an important factor in its pathogenicity whereas the ability of the CLARE isolate to grow on the lens in the presence of antimicrobial tear proteins may be important in the development of inflammation. 相似文献
14.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
15.
Rebecca J Sommer Adam J Hume Jessica M Ciak John J Vannostrand Megan Friggens Mary K Walker 《Toxicological sciences》2005,83(2):363-371
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) causes cardiovascular toxicity in laboratory animals, including alteration in several processes in which beta-adrenergic receptor (beta-AR) signaling plays important roles. Thus, our laboratory investigated the effects of TCDD on beta-AR expression and signal transduction. Fertile chicken eggs were injected with vehicle (corn oil), 0.24 or 0.3 pmol TCDD/g egg on incubation day 0 (D0) or D5. On D10, heart function was assessed by ECG in ovo. Exposure to TCDD increased the incidence of arrhythmias and decreased the positive chronotropic responsiveness of the heart to isoproterenol. The reduced beta-AR responsiveness was, in part, independent of any overt morphological changes in the heart as chick embryos exposed to TCDD on D5 displayed an intermediate responsiveness to beta-AR agonist in the absence of the dilated cardiomyopathy observed in chick embryos exposed to TCDD on D0. TCDD did not decrease the chronotropic response of the heart to agents that stimulate signals downstream of the beta-AR. In fact, TCDD-exposed embryos were more sensitive than controls to forskolin, increasing heart rates (HR) 21.8 +/- 3.5 beats per min (bpm) above baseline versus control values at 6.3 +/- 2.7 bpm above baseline. TCDD exposure also augmented the negative chronotropic response of the heart to verapamil, decreasing HR -23.2 +/- 7.4 bpm relative to baseline versus control embryos at -12.7 +/- 5.9 bpm below baseline. Finally, the mean cardiac beta1-AR mRNA expression in D10 embryos was not significantly altered by exposure to TCDD on D0. These findings establish that a functional end point of the developing chick heart is sensitive to TCDD exposure and that the TCDD-induced reduction in beta-AR responsiveness may result from alterations in signal transduction upstream of adenylyl cyclase. 相似文献
16.
The Mouse Secretome: Functional Classification of the Proteins Secreted Into the Extracellular Environment 总被引:1,自引:0,他引:1 下载免费PDF全文
17.
Spinocerebellar ataxia type 7 (SCA7): a neurodegenerative disorder with neuronal intranuclear inclusions 总被引:8,自引:13,他引:8
Holmberg M; Duyckaerts C; Durr A; Cancel G; Gourfinkel-An I; Damier P; Faucheux B; Trottier Y; Hirsch EC; Agid Y; Brice A 《Human molecular genetics》1998,7(5):913-918
Autosomal dominant cerebellar ataxia with progressive macular degeneration
is caused by a CAG/glutamine repeat expansion in the SCA7 gene/protein.
Neuronal intranuclear inclusions were detected in the brain of an early
onset SCA7 case with the 1C2 antibody directed against an expanded
polyglutamine domain. Nuclear inclusions were most frequent in the inferior
olivary complex, a site of severe neuronal loss in SCA7. They were also
observed in other brain regions, including the cerebral cortex, not
considered to be affected in the disease. Using confocal microscopy we
showed that some inclusions were ubiquitinated, but to varying degrees,
ranging from <1% in the cerebral cortex to 60% in the inferior olive. In
addition, we also observed cytoplasmic staining using the 1C2 antibody,
particularly in the supramarginal gyrus, the hippocampus, the thalamus, the
lateral geniculate body and the pontine nuclei. These data confirm that the
presence of intranuclear inclusions in neurons is a common characteristic
of disorders caused by CAG/polyglutamine expansions, but unlike what has
been reported for Huntington's disease, SCA1 and SCA3/MJD, in SCA7 the
inclusions were not restricted to the sites of severe neuronal loss.
相似文献
18.
The meaning of good sleep: a longitudinal study of polysomnography and subjective sleep quality 总被引:1,自引:1,他引:1
SUMMARY The present study sought to investigate the meaning of subjectively good sleep, using a longitudinal and intraindividual design. Eight subjects slept in an isolation unit according to an irregular schedule of 6h sleeps and 1h naps, designed to give normal amounts of time in bed (1/3 of total), but variable sleep quality. Eight sleeps and eight naps were used for longitudinal simple and multiple regression analyses with standard polysomnographical sleep variables as predictors and subjective sleep quality as dependent variables. The results showed that subjective sleep quality (and related variables) was closely related to sleep efficiency, but not sleep stages. At least 87% efficiency was required for ratings of 'rather good' sleep. In addition, sleep quality ratings improved with closeness (of the awakening) to the circadian acrophase (17.00–21.00 hours) of the rectal temperature rhythm. The subjective ease of awakening differed from most other other variables in that it was related to low sleep efficiency. Objective and subjective homologues of sleep length and sleep latency showed high mean intraindividual correlations ( r = 0.55 and 0.64, respectively). It was concluded that objective measures of sleep continuity were closely reflected in perceived sleep quality and that sleep quality essentially means sleep continuity. 相似文献
19.
C4a anaphylatoxin levels as an indicator of disease activity in systemic lupus erythematosus 总被引:1,自引:1,他引:1 下载免费PDF全文
G Wild J Watkins A M Ward P Hughes A Hume N R Rowell 《Clinical and experimental immunology》1990,80(2):167-170
The use of a synthetic protease inhibitor, nafamstat mesilate, has enabled reliable estimations of in vivo complement activation to be made in systemic lupus erythematosus (SLE). Elevation of C3a anaphylatoxins was found in two out of 24 patients and elevation of C4a anaphylatoxins was found in 20 out of 24 patients, confirming that complement activation, predominantly by the classical pathway, is a common occurrence in the disease. Significantly higher levels of C4a anaphylatoxin were found in 16 patients, with more aggressive disease requiring supplementary treatment with azathioprine, while the remaining eight patients, with less severe disease, required purely steroid therapy. Very strong associations between elevated C4a anaphylatoxins and raised DNA antibody titres, C1q binding activity and low complement C4 levels were also observed, suggesting that anaphylatoxin measurement may be a sensitive additional method for monitoring disease activity in SLE. 相似文献
20.
R. Hume 《Journal of clinical pathology》1966,19(4):389-391
Lean body mass, calculated from the measurement of total body water using antipyrine space, was estimated in 29 males and 27 females. It was found that the lean body mass could be predicted from the height and weight, and formulae for both males and females have been produced with multiple correlation coefficients (r) of 0.96 and 0.83 respectively. 相似文献