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51.
52.
Ofelia Dolores Hernández Ángel José Gutiérrez Dailos González‐Weller Gonzalo Lozano Enrique García Melón Carmen Rubio Arturo Hardisson 《Environmental toxicology》2010,25(3):227-233
This document shows the results obtained from a study on the concentration of toxic heavy metals in the internal tissue and exoskeleton of sea urchins, collected from their natural habitat. The levels of lead and cadmium were measured by Graphite Furnace Atomic Absorption Spectrometry. The mean concentrations of lead and cadmium in the internal tissue were 304.04 and 260.54 μg/kg respectively, whereas in the shell they were 185.02 and 142.48 μg/kg. We also performed a statistical analysis of the differences in the distribution of metals between their exoskeleton and their internal content, a correlation study of the metal content in internal tissue and shell and sampling areas, and a correlation study between the metal content and sample size. Since the sea urchin Diadema antillarum presents a wide range of variation in metal content, this study suggests that this species is an excellent bioindicator of heavy metal contamination. © 2009 Wiley Periodicals, Inc. Environ Toxicol, 2010. 相似文献
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54.
Seven DNA polymorphisms in the LDL receptor gene: application to the study of familial hypercholesterolemia in Spain 总被引:1,自引:0,他引:1
F. Javier Chaves Oscar Puig Magdalena Garcia-Sogo José Real José V. Gil Juan Ascaso Rafael Carmena M. Eugenia Armengod 《Clinical genetics》1996,50(1):28-35
We have performed restriction fragment length polymorphism (RFLP) analysis at the low density lipoprotein receptor (LDLR) locus in order to investigate the molecular genetics of familial hypercholesterolemia (FH) in Spain. Firstly, a sample of 50 unrelated patients with a clinical diagnosis of FH was screened for the presence of major rearrangements at this locus by Southern blot analysis of Bgt II digested genomic DNA. Four different mutations were detected, accounting for 8% of the mutant alleles in the Spanish FH sample. Then, we determined the relative allele frequency and estimated linkage disequilibrium between seven RFLPs of the LDLR gene in the remaining 46 FH patients and in 61 normolipidemic controls. Hindi, Avail, Pvu II, Msp I, and Nco I are the most polymorphic sites with individual PIC values higher than 0.28, whereas the Taq I and Stu I sites display low levels of polymorphism. The usefulness of the seven RFLPs to confirm a clinical diagnosis of FH was investigated in 15 FH-families, consisting of 118 individuals, in whom the presence of Familial Defective Apolipoprotein B-100 (FDB) due to the apoB3500 mutation was excluded. Independent haplotypes were constructed for 71 chromosomes: 15 FH and 56 control haplotypes. A total of 14 different haplotypes was found. In 12 families, clinical diagnosis of FH was confirmed by cosegregation analysis, which makes these RFLPs useful for studying the inheritance of the LDLR gene in 80% of Spanish families with FH. Comparison of haplotypes found in the Spanish sample with those found in Swiss and Norwegians suggests heterogeneity of haplotypes among European populations. 相似文献
55.
Histologic Classification of Endoscopically Removed Flat Colorectal Polyps: A Multicentric Study 总被引:1,自引:0,他引:1
A total of 594 flat colorectal polyps, removed at endoscopy, were histologically classified into non-neoplastic (n=49) and neoplastic (n=545) polyps. Non-neoplastic polyps were subdivided into metaplastic (n=45) and hyperplastic (n=4), whereas neoplastic polyps were subdivided into adenomas (n=481), intramucosal carcinomas (n=28) and invasive adenocarcinomas (n=36). Several adenoma phenotypes were discerned: tubular (n=375), serrated (n=59), villous (n=39), mixed (n=7) and fenestrated (n=1). Intramucosal carcinomas were subdivided into tubular (n=26) and serrated (n=2), and invasive adenocarcinomas into tubular (n=32), serrated (n=3) and fenestrated (n=1). The microscopic characteristics of each histologic phenotype described in this communication are defined and illustrated. 相似文献
56.
Field Tiffany; Hernandez-Reif Maria; Seligmen Susan; Krasnegor Josh; Sunshine William; Rivas-Chacon Rafael; Schanberg Saul; Kuhn Cynthia 《Journal of pediatric psychology》1997,22(5):607-617
Studied children with mild to moderate juvenile rheumatoid arthritiswho were massaged by their parents 15 minutes a day for 30 days(and a control group engaged in relaxation therapy). The children'sanxiety and stress hormone (cortisol) levels were immediatelydecreased by the massage, and over the 30-day period their paindecreased on self-reports, parent reports, and their physician'sassessment of pain (both the incidence and severity) and pain-limitingactivities 相似文献
57.
The presence of a resident T lymphocyte population in the meninges of normal SJL/J mice has been detected by the use of the T cell-specific mitogen concanavalin A. Optimal conditions for [3H]thymidine incorporation were studied. An antigen-specific meningeal T cell proliferative response in SJL/J mice, primed by intracerebral inoculation of Theiler's murine encephalomyelitis virus, was also detected. This response indicated that leptomeningeal mononuclear cell infiltrations are involved in the immune response that triggers the demyelinating disease. 相似文献
58.
59.
Josep Oriola Cristina Hernandez Rafael Simo Anna Barceló Roser Casamitjana Enric Vilardell & Francisca Rivera-Fillat 《Clinical endocrinology》1996,44(2):207-212
OBJECTIVE Genetic analysis is now essential for the accurate screening of families with multiple endocrine neoplasia type 2 (MEN2). We present the genetic analyses by both haplotype and direct RET proto-oncogene mutation analysis in seven Mediterranean MEN 2A families and have compared these results with biochemical screening tests and pathological examinations.
DESIGN Total DNA was extracted from leucocytes. Linkage analysis was performed using five RFLP systems from three loci that flank the MEN2A locus (FNRB, RBP3, D10S15). RET proto-oncogene analysis was carried out by automatic DNA sequencing and adequate digestion of PCR amplified products for exons 10 and 11. Screening for medullary thyroid carcinoma or C-cell hyperplasia was performed by the pentagastrin provocation test. Adrenal medullary function was assessed by measurements of 24-hour urinary excretion of catecholamines and their metabolites. Serum calcium and phosphate measurements were the initial screen for hyperparathyroidism. Serum PTH was determined only if hyperparathyroidism was suggested by the former determinations.
PATIENT Genetic study was performed in 59 individuals (39 at risk) from seven kindreds of Mediterranean origin with MEN 2A.
RESULTS Diagnosis by linkage analysis was not possible in 30% of individuals at risk, but RET proto-oncogene analysis identified all these individuals. Mutations of the RET proto-oncogene were detected in exon 10 (codon 618) in one MEN 2A kindred and in exon 11 (codon 634) in the others. The results of direct analysis were concordant with linkage studies in each case. Three individuals from different MEN 2A kindreds, who were subsequently shown not to be gene carriers, had false positive pentagastrin stimulation tests.
CONCLUSION Biochemical tests can be replaced by direct DNA mutation analysis as the first line screening test in order to identify gene carriers of MEN 2A. 相似文献
DESIGN Total DNA was extracted from leucocytes. Linkage analysis was performed using five RFLP systems from three loci that flank the MEN2A locus (FNRB, RBP3, D10S15). RET proto-oncogene analysis was carried out by automatic DNA sequencing and adequate digestion of PCR amplified products for exons 10 and 11. Screening for medullary thyroid carcinoma or C-cell hyperplasia was performed by the pentagastrin provocation test. Adrenal medullary function was assessed by measurements of 24-hour urinary excretion of catecholamines and their metabolites. Serum calcium and phosphate measurements were the initial screen for hyperparathyroidism. Serum PTH was determined only if hyperparathyroidism was suggested by the former determinations.
PATIENT Genetic study was performed in 59 individuals (39 at risk) from seven kindreds of Mediterranean origin with MEN 2A.
RESULTS Diagnosis by linkage analysis was not possible in 30% of individuals at risk, but RET proto-oncogene analysis identified all these individuals. Mutations of the RET proto-oncogene were detected in exon 10 (codon 618) in one MEN 2A kindred and in exon 11 (codon 634) in the others. The results of direct analysis were concordant with linkage studies in each case. Three individuals from different MEN 2A kindreds, who were subsequently shown not to be gene carriers, had false positive pentagastrin stimulation tests.
CONCLUSION Biochemical tests can be replaced by direct DNA mutation analysis as the first line screening test in order to identify gene carriers of MEN 2A. 相似文献
60.
Musculo-fibrous anomaly in Barrett's mucosa with dysplasia 总被引:1,自引:0,他引:1
We investigated the histological alterations occurring in the muscularis mucosae, the lamina propria mucosae, and the submucosa in areas adjacent to invasive adenocarcinoma in 32 resected esophagi with Barrett's mucosa. In 26 of the 32 specimens, we observed a thickening of the muscularis mucosae, with overgrowth of the muscle fibers into the lamina propria mucosae. In other areas, collagen-rich fibrotic tissue replaced the muscularis mucosae, the lamina propria mucosae, and even the submucosa. In 31 of the 32 specimens, we noted cystic dilatations of the esophageal glands. Normal esophageal glands and cystically dilated glands with dysplastic lining were often surrounded, compressed, and deformed by the fibrotic tissue. The compression of the glandular outlets by the collagen-rich tissue or by proliferating dysplastic cells appeared to be the two main factors in the histogenesis of these cysts. This may result in difficulty in differentiating, in biopsy specimens, between normal and dysplastic esophageal glands "trapped" in the collagen-rich fibrotic tissue and true invasive adenocarcinoma in the Barrett's mucosa. 相似文献