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11.
12.
Congenital abnormal communications between separated pulmonary tissue and the oesophagus are rarities. Only about 50 cases have been reported in the literature. For all different forms the term of bronchopulmonary foregut malformation (BPFM) was first applied by Gerle and his coworkers in 1968. Major symptoms of this condition involved respiratory distress, cough, dyspnea, vomiting and repeated pneumonia. This paper presents reports of two own patients. In both cases was confirmed a bronchopulmonary foregut malformation in the lower right thorax with ectopic main bronchus communicating into the distal oesophagus. According to the literature we describe our own experience and discuss embryologic pathogenesis and surgical consequences for children. 相似文献
13.
The metabolic activation of the heterocyclic food carcinogen 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) by two human cytochrome P450 monoxygenases (P4501A1 and P4501A2) and two human N-acetyltransferases (NAT1 and NAT2) was investigated. Various combinations of these enzymes were functionally expressed in COS-1 cells. DNA adducts resulting from the activation of IQ were assayed quantitatively by the 32P-postlabeling procedure. The highest adduct frequency was observed in cells expressing both CYP1A2 and NAT2. CYP1A2 in combination with NAT1 was 3-6 times less active. When expressed alone these enzymes gave rise to low adduct frequencies. Experiments with N-acetyl-IQ as substrate suggest that NAT1 and NAT2 in addition to their known role in N-acetylation display arylhydroxamic acid N, O-acetyltransferase (AHAT) activity. Quantitative differences in adduct formation between IQ and N-acetyl-IQ indicated that metabolic activation of these arylamines preferentially occurs by P4501A2-catalyzed N-hydroxylation followed by O-acetylation mediated through NAT1 and/or NAT2. These data, in combination with the known genetic polymorphism of NAT2, may explain the clinical observation that the acetylation polymorphism constitutes a risk factor in the carcinogenic activation of environmental mutagens. 相似文献
14.
L. Simonato J. J. Moulin B. Javelaud G. Ferro P. Wild R. Winkelmann R. Saracci 《American journal of industrial medicine》1994,25(5):625-633
A historical mortality study of a cohort of employees of a gold mining and refining company was carried out in Salsigne, France. A major goal of the study was to investigate the relationship between lung cancer mortality and exposure to arsenic, radon, silica, and other contaminants of the working environment. A twofold excess of lung cancer was found both among miners and smelters, mainly concentrated among workers who had experienced exposure to past levels of arsenic, radon, and silica. The consistency of the results in the mine and the refinery are suggestive of a carcinogenic risk from both soluble and insoluble arsenic, although the potential role of other factors cannot be dismissed. © 1994 Wiley-Liss, Inc. 相似文献
15.
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
16.
Leukotriene B4 (LTB4) and the protein kinase C activator, 4-beta-phorbol dibutyrate (PDBu), both induced a pronounced and concentration-dependent stimulation of hydrogen peroxide (H2O2) generation by purified guinea pig peritoneal eosinophils in the concentration range 1 nM-1 microM. The LTB4 response was inhibited competitively by the specific LTB4 receptor antagonist, U-75302, with a KB of 25 nM, while the concentration-response curves for both stimuli were shifted rightwards (3.8-fold and 2.8-fold for LTB4 and PDBu, respectively) by the competitive protein kinase C inhibitor, 1-O-hexadecyl-2-O-methylglycerol at a concentration of 300 microM. LTB4 appears, therefore, to induce respiratory burst in eosinophils via a receptor-mediated mechanism involving protein kinase C. 相似文献
17.
J J Moulin J M Mur P Wild A Demonchy E Eloy A Jeannot 《Revue d'épidémiologie et de santé publique》1988,36(2):99-107
A mortality study was carried out, throughout the period 1970-1984, in a cohort of 963 men who had worked for at least one year in a coal tar distillery. The observed number of deaths, 109, did not significantly differ from the expected number. Using the death rates of the local population as a reference, no excess was observed for lung cancer and for cancers of the larynx, while there was an excess for cancers of the oesophagus but non significant and for cancers of the buccal cavity and pharynx (SMR = 2.17 - p less than 0.05). A nested case-control study was carried out. From within the cohort, 5 deaths from lung cancer and 10 deaths from cancers of the buccal cavity and pharynx were defined as "cases". For each case, all the available dead controls with the same sex, year of birth, tobacco and alcohol consumption were selected from within the cohort. The odds ratios for lung cancer did not reveal any occupational risk. With regard to buccal cavity and pharyngeal cancers, the odds ratios were neither significant for a duration of exposure greater than or equal to 1 year nor for a duration greater than or equal to 5 years along with a latent period greater than or equal to 10 years. Nevertheless there is a significant OR for exposure less than or equal to 10 years (OR = 7.56) but it is near one for exposures greater than 10 years. 相似文献
18.
Localization of a gene for otosclerosis to chromosome 15q25-q26 总被引:5,自引:0,他引:5
Tomek MS; Brown MR; Mani SR; Ramesh A; Srisailapathy CR; Coucke P; Zbar RI; Bell AM; McGuirt WT; Fukushima K; Willems PJ; Van Camp G; Smith RJ 《Human molecular genetics》1998,7(2):285-290
Among white adults otosclerosis is the single most common cause of hearing
impairment. Although the genetics of this disease are controversial, the
majority of studies indicate autosomal dominant inheritance with reduced
penetrance. We studied a large multi- generational family in which
otosclerosis has been inherited in an autosomal dominant pattern. Five of16
affected persons have surgically confirmed otosclerosis; the remaining nine
have a conductive hearing loss but have not undergone corrective surgery.
To locate the disease- causing gene we completed genetic linkage analysis
using short tandem repeat polymorphisms (STRPs) distributed over the entire
genome. Multipoint linkage analysis showed that only one genomic region, on
chromosome 15q, generated a lod score >2.0. Additional STRPs were typed
in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and
D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis
gene.
相似文献
19.
20.
Association of DLG5 R30Q variant with inflammatory bowel disease 总被引:6,自引:0,他引:6
Daly MJ Pearce AV Farwell L Fisher SA Latiano A Prescott NJ Forbes A Mansfield J Sanderson J Langelier D Cohen A Bitton A Wild G Lewis CM Annese V Mathew CG Rioux JD 《European journal of human genetics : EJHG》2005,13(7):835-839
Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory diseases of the gastrointestinal system known as the inflammatory bowel diseases (IBD). Recently, Stoll and colleagues reported a novel finding of genetic variation in the DLG5 gene that is associated with IBD (CD and UC combined). We present here a study of the genetic variation described in that report in two well-powered, independent case-control cohorts and one family-based collection, and confirm the proposed association between IBD and the R30Q variant of DLG5 in two of the three studies. We are, however, unable to replicate the other proposed association to the common haplotype described in Stoll et al and suggest that this other finding could conceivably have been partially a statistical fluctuation and partially a result of LD with the replicated R30Q association. This study provides support for the hypothesis that DLG5 constitutes a true IBD risk factor of modest effect. 相似文献