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991.
PURPOSE: To compare the performances of computed tomography (CT) and water soluble contrast enema in the diagnosis and evaluation of the severity of acute left colonic diverticulitis, and to propose indications for elective colectomy after a first episode of diverticulitis successfully treated medically. PATIENTS AND METHODS: Prospective non-randomized study (1986-1997) of 542 patients (290 women and 252 men with a median age of 64 years) whose final diagnosis was confirmed either histologically or radiologically. 465 patients (86%) had a CT, 439 (81%) had a water soluble contrast enema, and 420 (77%) had both examinations. Diverticulitis was considered moderate when CT showed localized thickening of colonic wall (> or = 5 mm) and inflammation of pericolic fat and water soluble contrast enema showed segmental lumen narrowing and tattered mucosa; it was considered severe when abscess and/or extraluminal air/or extraluminal contrast were described by CT or the two latter by water soluble contrast enema. RESULTS: 410 patients (76%) were treated medically and 132 were operated during their hospitalization. Sensitivity of CT for diagnosis of diverticulitis was 96%, compared to 87% for water soluble contrast enema (p < 0.0001). Severe diverticulitis was found in 139 patients (30%) by CT and in 45 patients (11%) by water soluble contrast enema (p < 0.0001). Age < or = 50 years, severe diverticulitis in the initial CT and associated pelvic abscess were found to be statistically significant parameters to predict the risk of secondary complications after a first episode of diverticulitis successfully treated medically. CONCLUSIONS: Performances of CT for diagnosis and evaluation of severity of acute diverticulitis are statistically higher than that of water soluble contrast enema. We would recommend elective colectomy in patients 50 years of age or younger with a severe diverticulitis in initial CT, and in all patients with an associated pelvic abscess. 相似文献
992.
Geneviève D Sanlaville D Faivre L Kottler ML Jambou M Gosset P Boustani-Samara D Pinto G Ozilou C Abeguilé G Munnich A Romana S Raoul O Cormier-Daire V Vekemans M 《European journal of human genetics : EJHG》2005,13(9):1033-1039
Deletions of the long arm of chromosome 20 are rare. Here, we report on two girls with a very small interstitial deletion of the long arm of chromosome 20 presenting with severe pre- and post-natal growth retardation, intractable feeding difficulties, abnormal subcutaneous adipose tissue, similar facial dysmorphism, psychomotor retardation and hypotonia. Standard cytogenetic studies were normal, but high-resolution chromosomes analysis showed the presence of a chromosome (20)(q13.2-q13.3) interstitial deletion. Karyotypes of both parents were normal. Molecular studies using FISH and microsatellite polymorphic markers showed that the deletion was of paternal origin and was approximatively 4.5 Mb in size. A review of other reported patients with similar deletions of the long arm of chromosome 20 shows that the observed phenotype might be explained in the light of the GNAS imprinted locus in particular by the absence of the Gnasxl paternally imprinted gene and the TFA2PC gene in the deleted genetic interval. 相似文献
993.
Primignani P Castorina P Sironi F Curcio C Ambrosetti U Coviello DA 《Clinical genetics》2003,63(6):516-521
Mutations of the GJB2 gene, encoding Connexin 26, are the most common cause of hereditary congenital hearing loss in many countries, and account for up to 50% of cases of autosomal-recessive non-syndromic deafness. By contrast, only a few GJB2 mutations have been reported to cause an autosomal-dominant form of non-syndromic deafness. We report on a family from southern Italy in whom dominant, non-syndromic, post-lingual hearing loss is associated with a novel missense mutation in the GJB2 gene. Direct sequencing of the gene showed a heterozygous G-->A transition at nucleotide 535, resulting in an aspartic acid to asparagine amino acid substitution at codon 179 (D179N). This mutation occurred in the second extracellular domain (EC2), which would seem to be very important for connexon-connexon interaction. 相似文献
994.
Gauthier A Davenne D Martin A Van Hoecke J 《European journal of applied physiology》2001,84(3):249-252
The aim of this study was, firstly, to confirm or refute the existence of circadian rhythms during several velocities of
concentric action of the elbow flexor muscles and, secondly, to compare the characteristics of these circadian rhythms with
those obtained during isometric actions. Eight volunteer subjects participated in this study. The circadian rhythms were obtained
from six test sessions (TS) carried out at different times of day over 6 days with only one TS a day. During each TS, oral
temperature and the torque of the muscle action were measured. The subjects made, on an isokinetic ergometer, two maximal
isokinetic concentric elbow flexions at five angular velocities (60, 120, 180, 240 and 300° · s−1) and at an angle of 60°. Torque-angular velocity relationships, which characterised the functioning of the muscle during
concentric and isometric actions, were established for the different times of day. The values of the torque recorded at each
of the angular velocities presented a clear circadian rhythm. After normalisation of the torque values, no significant differences
were observed among the computed characteristics of the circadian rhythms obtained at different angular velocities. Since
the circadian rhythms during isometric and concentric torque were the same, the characteristics of the circadian rhythms of
the musculo-skeletal system can be studied using either type of muscle action. The results indicated that torque and temperature
varied concomitantly during the day. Thus, the recording of body temperature allows one to estimate the times of occurrence
of maximal and minimal values in the circadian rhythm of muscle torque.
Accepted: 10 October 2000 相似文献
995.
Thacker John; Ganesh Anil N.; Stretch Albert; Benjamin Damien M.; Zahalsky Andrew J.; Hendrickson Eric A. 《Mutagenesis》1994,9(2):163-168
lines irs1, irs2 and irs3, derived from V79-4 hamster cells,are sensitive to DNA-damaging agents including ionizing radiations.However, unlike some other radiosensitive lines, the irs linesshow no apparent defect in the repair of DNA strand breaks.We have now assessed the mis-repair of DNA damage in the irslines by measuring spontaneous and X-ray induced frequenciesof mutation in the HPRT gene, irsl was found to be hypermutable,showing instability in spontaneous mutant frequency and an elevationof the radiation-induced frequency relative to the parentalline. In contrast, irs2 and irs3 showed similar mutational responsesto the parental line. The results support other lines of evidencesuggesting that irs1 has a mis-repair phenotype. The irs2 linehas previously been shown to have a phenotype similar to cellsfrom the human disorder ataxia-telangiectasia and this similarityis maintained in their mutational response to X-rays. The irslines were also tested for ability to undergo V(D)J recombination,since this process has recently been found to be defective insome radiosensitive lines with impaired double-strand breakrepair. Using an extrachromosomal vector containing a V(D)Jrearrangement cassette, correct recombination was shown to occurat similar frequencies to parental V79-4 cells in each of thethree irs lines. Thus the irs lines indicate that processesother than DNA double-strand break repair also control radiosensitivity,in particular those processes which may affect the regulationof DNA repair. 相似文献
996.
Up-regulated expression of ADAM17 in human colon carcinoma: co-expression with EGFR in neoplastic and endothelial cells 总被引:7,自引:0,他引:7
Blanchot-Jossic F Jarry A Masson D Bach-Ngohou K Paineau J Denis MG Laboisse CL Mosnier JF 《The Journal of pathology》2005,207(2):156-163
The ADAM17 metalloproteinase (a disintegrin and metalloprotease 17) controls epidermal growth factor receptor (EGFR) activation through regulated shedding of EGFR ligands. With the advent of new therapeutic options targeting EGFR signalling in colon carcinoma, it was decided to determine ADAM17 status in relation to clinico-pathological parameters and EGFR status. To this end, a series of 39 colon carcinomas were analysed. Immunohistochemistry and immunofluorescence were used to localize ADAM17, EGFR, and the activated forms of EGFR. The activated form of ADAM17 was assessed in primary cancers and colon cell lines by immunoblotting. ADAM17 and EGFR mRNA levels were assessed by quantitative RT-PCR. Chromogenic in situ hybridization (CISH) was used to quantify the HER1 gene. ADAM17 was strongly expressed in all tumours, by both neoplastic and endothelial cells. It was expressed both as a pro- and as an active form in tumours and colonic cancer cell lines. ADAM17 mRNA was up-regulated in 90% of colon carcinomas relative to the paired normal mucosa, whatever the tumour grade or stage. When present, activated EGFR was co-expressed with ADAM17 by colon carcinomas, although at a variable level among tumour cells, and by endothelial cells. EGFR mRNA was overexpressed in 77% of colon carcinomas compared with the paired normal mucosa. One case showed high-level amplification of HER1. In conclusion, this study is the first demonstration that ADAM17 is overexpressed in human primary colon carcinoma, whatever the tumour stage and differentiation and whatever the level of EGFR expression. Its co-expression with EGFR, in both neoplastic and endothelial cells, suggests a role for ADAM17 in tumour growth and angiogenesis. 相似文献
997.
Detection and verification of Mycobacterium avium subsp. paratuberculosis in fresh ileocolonic mucosal biopsy specimens from individuals with and without Crohn's disease 总被引:4,自引:0,他引:4
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Bull TJ McMinn EJ Sidi-Boumedine K Skull A Durkin D Neild P Rhodes G Pickup R Hermon-Taylor J 《Journal of clinical microbiology》2003,41(7):2915-2923
Mycobacterium avium subsp. paratuberculosis is a robust and phenotypically versatile pathogen which causes chronic inflammation of the intestine in many species, including primates. M. avium subsp. paratuberculosis infection is widespread in domestic livestock and is present in retail pasteurized cows' milk in the United Kingdom and, potentially, elsewhere. Water supplies are also at risk. The involvement of M. avium subsp. paratuberculosis in Crohn's disease (CD) in humans has been uncertain because of the substantial difficulties in detecting this pathogen. In its Ziehl-Neelsen staining-negative form, M. avium subsp. paratuberculosis is highly resistant to chemical and enzymatic lysis. The present study describes the development of optimized sample processing and DNA extraction procedures with fresh human intestinal mucosal biopsy specimens which ensure access to M. avium subsp. paratuberculosis DNA and maximize detection of these low-abundance pathogens. Also described are two nested PCR methodologies targeted at IS900, designated IS900[L/AV] and IS900[TJ1-4], which are uniquely specific for IS900. Detection of M. avium subsp. paratuberculosis in mucosal biopsy specimens was also evaluated by using mycobacterial growth indicator tube (MGIT) cultures (Becton Dickinson). IS900[L/AV] PCR detected M. avium subsp. paratuberculosis in 34 of 37 (92%) patients with CD and in 9 of 34 (26%) controls without CD (noninflammatory bowel disease [nIBD] controls) (P = 0.0002; odds ratio = 3.47). M. avium subsp. paratuberculosis was detected by IS900[L/AV] PCR in MGIT cultures after 14 to 88 weeks of incubation in 14 of 33 (42%) CD patients and 3 of 33 (9%) nIBD controls (P = 0.0019; odds ratio = 4.66). Nine of 15 (60%) MGIT cultures of specimens from CD patients incubated for more than 38 weeks were positive for M. avium subsp. paratuberculosis. In each case the identity of IS900 from M. avium subsp. paratuberculosis was verified by amplicon sequencing. The rate of detection of M. avium subsp. paratuberculosis in individuals with CD is highly significant and implicates this chronic enteric pathogen in disease causation. 相似文献
998.
T-cell-stimulating protein A elicits immune responses during meningococcal carriage and human disease
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Robinson K Wooldridge KG Wells DB Hasan A Todd I Robins A James R Ala'Aldeen DA 《Infection and immunity》2005,73(8):4684-4693
In recognition of the need for immunological memory-inducing components for future Neisseria meningitidis group B vaccines, we previously searched the proteome of N. meningitidis and identified T-cell-stimulating protein A (TspA). This study was designed to confirm the immunogencity of TspA and to examine the subset of T-helper cell responses to the protein in patients and nasopharyngeal carriers. The tspA gene was reconstructed, cloned, and expressed in Escherichia coli, and the recombinant TspA (rTspA) protein was affinity purified. T-cell proliferative responses to rTspA were detected in the peripheral blood mononuclear cells (PBMCs) of convalescent patients and carriers, confirming that TspA-specific T-cell responses were stimulated by invasive disease and nasopharyngeal colonization. Following stimulation of PBMCs with meningococcal lysate, increased frequencies of both Th1 and Th2 cells were observed, indicating that, as during carriage, invasive meningococcal disease induced an unbiased T-helper subset response. A similar unbiased T-helper response was also detected against rTspA in the PBMCs of convalescent patients. The response of PBMCs from the carriers to TspA stimulation, however, was very weak, and the frequencies of cytokine-positive CD4 cells were not significantly greater than the frequencies in unstimulated control cultures. All of the patients and carriers responded with serum antimeningococcal immunoglobulin G (IgG) antibodies, while four of six samples from patients and 5 of 14 samples from carriers contained detectable anti-rTspA IgG antibodies. Taken together, the results of this study confirmed the immunogenicity of TspA in humans during natural meningococcal infection, and therefore, TspA is worthy of further investigation as a possible T-cell stimulating component of future vaccines. 相似文献
999.
Robilliard DL Archer SN Arendt J Lockley SW Hack LM English J Leger D Smits MG Williams A Skene DJ Von Schantz M 《Journal of sleep research》2002,11(4):305-312
Mutations in clock genes are associated with abnormal circadian parameters, including sleep. An association has been reported previously between a polymorphism (3111C), situated in the 3'-untranslated region (3'-UTR) of the circadian gene Clock and evening preference. In the present study, this polymorphism was assessed in: (1) 105 control subjects with defined diurnal preference, (2) 26 blind subjects with free-running circadian rhythms and characterized with regard to circadian period (tau) and (3) 16 delayed sleep phase syndrome patients. The control group was chosen from a larger population (n = 484) by Horne-Ostberg questionnaire analysis, from which three subgroups were selected (evening, intermediate and morning preference). Data from sleep diaries completed by 90% of these subjects showed a strong correlation between preferred and estimated timings of sleep and wake. The mean timings of activities for the evening group were at least 2 h later than the morning group. Genetic analysis showed that, in contrast with the previously published finding, there was no association between 3111C and eveningness. Neither was there an association between 3111C and tau, nor a significant difference in 3111C frequency between the normal and delayed sleep phase syndrome groups. To assess the effect of this polymorphism on messenger RNA (mRNA) translatability, luciferase reporter gene constructs containing the two Clock polymorphic variants in their 3'-UTR were transfected into COS-1 cells and luciferase activity measured. No significant difference was observed between the two variants. These results do not support Clock 3111C as a marker for diurnal preference, tau, or delayed sleep phase syndrome in humans. 相似文献
1000.
Carcinosarcoma of the uterine cervix is a rare tumor. A case of carcinosarcoma of uterine cervix initially interpreted as sarcoma, NOS, is presented along with immunohistochemical findings. 相似文献