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61.
Larsen TB Nielsen JN Fredholm L Lund ED Brandslund I Munkholm P Hey H 《Pathophysiology of haemostasis and thrombosis》2002,32(2):92-96
Patients with inflammatory bowel disease (IBD) are susceptible to thromboembolic complications. Several mechanisms can be responsible, including abnormal regulation of coagulation activity, disturbances of fibrinolysis, inflammatory reactions and thrombocytosis. The aim of this study was to assess hemostatic alterations in these parameters during exacerbation of disease. We studied disease activity in 99 IBD patients receiving anti-inflammatory therapy, in relation to: procoagulant markers, i.e. prothrombin fragment F1 + 2 (F1 + 2), D-dimer and platelet count, anticoagulant markers, i.e. protein C, protein S and antithrombin, and a mediator of inflammation (IL-6). Coagulation activity and platelet count were increased during active disease in IBD patients compared with those in a state of remission. The IL-6 concentrations were positively correlated with disease activity and thrombocytosis in patients with ulcerative colitis, but no association with the anticoagulant capacity could be demonstrated except for a decrease in protein C during high disease activity. 相似文献
62.
J. G. Villa G. Cuadrado J. E. Bayón J. González-Gallego 《European journal of applied physiology》1997,77(1-2):106-111
The effects of physical conditioning on antipyrine clearance were studied in two groups of subjects. Healthy men not engaged
in the systematic practice of any sport were compared with endurance runners (defined as men running >80 km/week). Studies
were carried out at three different periods of the annual plan training at 4-month intervals. Antipyrine was administered
orally and pharmacokinetic parameters were obtained from saliva samples by the multiple-sample method. Endurance performance,
expressed in terms of the maximal oxygen uptake (V˙O2
max), the ventilatory threshold and the 4-mM · l−1 lactate threshold (OBLA), was higher in trained than in control subjects at each of the three periods. Antipyrine clearance
was also significantly elevated and antipyrine half-life reduced in runners during all periods. No significant difference
in V˙O2
max or antipyrine clearance was found between the various periods in either trained or control subjects. Both ventilatory threshold
and OBLA increased significantly along the training period in conditioned subjects. Significant correlations were found between
antipyrine clearance and V˙O2
max, ventilatory threshold and OBLA. In summary, these results indicate an association between aerobic conditioning and increased
hepatic oxidative metabolism of low-clearance drugs.
Accepted: 15 July 1997 相似文献
63.
A CD4+ T cell line-secreted factor, growth promoting for normal and leukemic B cells, identified as thioredoxin 总被引:6,自引:0,他引:6
64.
Pericentric inversions of chromosome 4: report of a new family and review of the literature 总被引:1,自引:0,他引:1
A. Villa M. Urioste M. C. Carrascosa S. Vázquez A. Martínez M. L. Martínez-Frías 《Clinical genetics》1995,48(5):255-260
A family was cytogenetically studied because of the birth of a male child with a multiple congenital anomaly pattern, in whom a dup (4q) recombinant was found. His phenotypically normal mother's karyotype showed an apparently balanced pericentric inversion in a chromosome 4. So as to analyze the occurrence of recombinants, the cytogenetic data from this family are compared with those of the 18 previously reported familial cases of pericentric inversions (PIs) of chromosome 4. The congenital anomalies observed in the child strongly suggest Wolf-Hirschhorn syndrome but some of his clinical features seem to be pathogenetically related to the presence of lymphedema during the intrauterine period. In the multiple congenital anomaly pattern observed in this patient, the lymphedema could be the consequence of the large 4q duplication. The review of chromosome 4 PIs with 4q duplication suggests that the q3 region should be examined when edema is detected prenatally. 相似文献
65.
E. M. Rouiller G. M. Simm A. E. P. Villa Y. de Ribaupierre F. de Ribaupierre 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,86(3):483-505
Summary The origin and laminar arrangement of the homolateral and callosal projections to the anterior (AAF), primary (AI), posterior (PAF) and secondary (AII) auditory cortical areas were studied in the cat by means of electrophysiological recording and WGA-HRP tracing techniques. The transcallosal projections to AAF, AI, PAF and AII were principally homotypic since the major source of input was their corresponding area in the contralateral cortex. Heterotypic transcallosal projections to AAF and AI were seen, originating from the contralateral AI and AAF, respectively. PAF received heterotypic commissural projections from the opposite ventroposterior auditory cortical field (VPAF). Heterotypic callosal inputs to AII were rare, originating from AAF and AI. The neurons of origin of the transcallosal connections were located mainly in layers II and III (70–92%), and less frequently in deep layers (V and VI, 8–30%). Single unit recordings provided evidence that both homotypic and heterotypic transcallosal projections connect corresponding frequency regions of the two hemispheres. The regional distribution of the anterogradely labeled terminals indicated that the homotypic and heterotypic auditory transcallosal projections are reciprocal. The present data suggest that the transcallosal auditory interconnections are segregated in 3 major parallel components (AAF-AI, PAF-VPAF and AII), maintaining a segregation between parallel functional channels already established for the thalamocortical auditory interconnections. For the intrahemispheric connections, the analysis of the retrograde tracing data revealed that AAF and AI receive projections from the homolateral cortical areas PAF, VPAF and AII, whose neurons of origin were located mainly in their deep (V and VI) cortical layers. The reciprocal interconnections between the homolateral AAF and AI did not show a preferential laminar arrangement since the neurons of origin were distributed almost evenly in both superficial (II and III) and deep (V and VI) cortical layers. On the contrary, PAF received inputs from the homolateral cortical fields AAF, AI, AII and VPAF, originating predominantly from their superficial (II and III) layers. The homolateral projections reaching AII originated mainly from the superficial layers of AAF and AI, but from the deep layers of VPAF and PAF. The laminar distribution of anterogradely labeled terminal fields, when they were dense enough for a confident identification, was systematically related to the laminar arrangement of neurons of origin of the reciprocal projection: a projection originating from deep layers was associated with a reciprocal projection terminating mainly in layer IV, whereas a projection originating from superficial layers was associated with a reciprocal projection terminating predominantly outside layer IV. This laminar distribution indicates that the homolateral auditory cortical interconnections have a feed-forward/feed-back organization, corresponding to a hierarchical arrangement of the auditory cortical areas, according to criteria previously established in the visual system of primates. The principal auditory cortical areas could be ranked into 4 distinct hierarchical levels. The tonotopically organized areas AAF and AI represent the lowest level. The second level corresponds to the non-tonotopically organized area AII. Higher, the tonotopically organized areas VPAF and PAF occupy the third and fourth hierarchical levels, respectively.Abbreviations AAF
anterior auditory cortical area
- AI
primary auditory cortical area
- AII
secondary auditory cortical area
- BF
best frequency
- C
cerebral cortex
- CA
caudate nucleus
- CL
claustrum
- D
dorsal nucleus of the dorsal division of the MGB
- ea
anterior ectosylvian sulcus
- ep
posterior ectosylviansulcus
- IC
internal capsule
- LGN
lateral geniculate nucleus
- LV
pars lateralis of the ventral division of the MGB
- LVe
lateral ventricule
- M
pars magnocellularis of the medial division of the MGB
- MGB
medial geniculate body
- MGBv
ventral division of the MGB
- OT
optic tract
- OV
pars ovoidea of the ventral division of the MGB
- PAF
posterior auditory cortical area
- PH
parahippocampal cortex
- PO
lateral part of the posterior group of thalamic nuclei
- PU
putamen
- RE
reticular complex of thalamus
- rs
rhinal sulcus
- SG
suprageniculate nucleus of the dorsal division of the MGB
- ss
suprasylvian sulcus
- TMB
tetrametylbenzidine
- VBX
ventrobasal complex
- VLa
ventrolateral complex
- VL
ventro-lateral nucleus of the ventral division of the MGB
- WGA-HRP
wheat germ agglutinin conjugated to horse-radish peroxidase
- WM
white matter
- VPAF
ventro-posterior auditory cortical area 相似文献
66.
The cellular infiltration found during CNS inflammation consists of monocytes and activated T cells, suggesting the presence of cell-specific chemotactic signals during inflammatory responses. Astrocyte chemokine expression might contribute to site-specific leukocyte infiltration within the CNS. To investigate the factors that regulate astrocyte chemokine expression, we examined the ability of human fetal astrocytes to induce -family chemokine mRNA. Astrocyte-derived monocyte chemoattractant protein-1 (MCP-1), RANTES, macrophage inflammatory protein-1 (MIP-1), and MIP-1 mRNA were easily induced by lipopolysaccharide and/or the proinflammatory cytokines (IFN and/or TNF-), respectively. Addition of both IFN and TNF- together did not lead to an additive effect but resulted in the inhibition of MCP-1 and MIP-1 mRNA expression, indicating that interaction between chemokines and cytokines may play a key role in regulating the local immune response of resident and infiltrating cells at the site of lesion. Interestingly, ultraviolet light-inactivated measles virus, but not cytomegalovirus, strongly induced expression of MCP-1, RANTES, MIP-1, and MIP-1 mRNA in human embryonic astrocytes, especially MCP-1 and MIP-1. An association occurs between the -family chemokine expression in astrocytes and inflammatory factors/virus, suggesting a possible role for -family chemokines in the pathogenesis of CNS inflammatory disease. 相似文献
67.
68.
Mucosal FOXP3-expressing CD4+ CD25high regulatory T cells in Helicobacter pylori-infected patients 总被引:2,自引:0,他引:2
Lundgren A Strömberg E Sjöling A Lindholm C Enarsson K Edebo A Johnsson E Suri-Payer E Larsson P Rudin A Svennerholm AM Lundin BS 《Infection and immunity》2005,73(1):523-531
Helicobacter pylori chronically colonizes the stomach and duodenum and causes peptic ulcers or gastric adenocarcinoma in 10 to 20% of infected individuals. We hypothesize that the inability of patients to clear H. pylori infections is a consequence of active suppression of the immune response. Here we show that H. pylori-infected individuals have increased frequencies of CD4(+) CD25(high) T cells in both the stomach and duodenal mucosa compared to uninfected controls. These cells have the phenotype of regulatory T cells, as they express FOXP3, a key gene for the development and function of regulatory T cells, as well as high levels of the cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) protein. In contrast, mucosal CD4(+) CD25(low) and CD4(+) CD25(-) cells express little FOXP3 mRNA and low levels of the CTLA-4 protein. Mucosal CD4(+) CD25(high) T cells are present in individuals with asymptomatic H. pylori infections as well as in duodenal ulcer patients. The frequencies of CD4(+) CD25(high) cells are also increased in the stomachs of H. pylori-infected patients with gastric adenocarcinoma, particularly in cancer-affected tissues. These findings suggest that regulatory T cells may suppress mucosal immune responses and thereby contribute to the persistence of H. pylori infections. 相似文献
69.
Hofstra RM Mulder IM Vossen R de Koning-Gans PA Kraak M Ginjaar IB van der Hout AH Bakker E Buys CH van Ommen GJ van Essen AJ den Dunnen JT 《Human mutation》2004,23(1):57-66
Duchenne and Becker muscular dystrophy (DMD and BMD) are caused by mutations in the dystrophin gene. Large rearrangements in the gene are found in about two-thirds of DMD patients, with approximately 60% carrying deletions and 5-10% carrying duplications. Most of the remaining 30-35% of patients are expected to have small nucleotide substitutions, insertions, or deletions. To detect these subtle changes within the coding and splice site determining sequences of the dystrophin gene, we established a semiautomated denaturing gradient gel electrophoresis (DGGE) mutation scanning system. The DGGE scan covers the dystrophin gene with 95 amplicons, PCRed either individually or in a multiplex setup. PCR and pooling were performed semiautomatically, using a pipetting robot and 384-well plates, enabling concurrent amplification of DNA of four patients in one run. Amplification of individual fragments was performed using one PCR program. The products were pooled just before gel loading; DGGE requires only a single gel condition. Validation was performed using DNA samples harboring 39 known DMD variants, all of which could be readily detected. DGGE mutation scanning was applied to analyze 135 DMD/BMD patients and potential DMD carriers without large deletions or duplications. In DNA from 25 out of 44 DMD patients (57%) and from 5 out of 39 BMD patients (13%), we identified clear pathogenic changes. All mutations were different, with the exception of one DMD mutation, which occurred twice. In DNA from 10 out of 44 potential DMD carriers, including four obligate carriers, we detected causative changes, including one pathogenic change in every obligate carrier. In addition to these pathogenic changes, we detected 15 unique unclassified variants, i.e., changes for which a pathogenic nature is uncertain. 相似文献
70.
Analysis of human papillomavirus prevalence and TP53 polymorphism in head and neck squamous cell carcinomas 总被引:1,自引:0,他引:1
Cortezzi SS Provazzi PJ Sobrinho JS Mann-Prado JC Reis PM de Freitas SE Filho JF Fukuyama EE Cordeiro JA Cury PM Maniglia JV Villa LL Tajara EH Rahal P 《Cancer Genetics and Cytogenetics》2004,150(1):44-49
Head and neck squamous cell carcinoma is a disease associated with tobacco and alcohol abuse. There is evidence that the oncogenic human papillomavirus (HPV) may also be a risk for upper aerodigestive tract cancers. High-risk HPVs encode two early proteins, E6 and E7, that can bind to p53 and pRb, respectively, and induce its degradation or inactivation. The TP53 gene has a single polymorphism at codon 72 of exon 4 that encodes either arginine (Arg) or proline (Pro). The purpose of this study was to evaluate the role of HPV infection and TP53 polymorphism in head and neck cancer. We analyzed 50 tumors, as well swabs of oral mucosa from 142 control individuals, with a polymerase chain reaction technique. The prevalence of HPV in controls was 10.6% and in cancer specimens 16%. The frequency distribution of genotypes in controls was 50% Arg/Arg, 43% Arg/Pro and 7% Pro/Pro; in tumors, it was 52% Arg/Arg, 32% Arg/Pro, and 16% Pro/Pro. Contrary to the results of some studies on cervical cancer, no association between any TP53 genotype or allele and the development of head and neck cancer was observed, regardless of HPV status, except for the Pro/Pro genotype, which is associated with the absence of HPV. The arginine allele appears to protect against head and neck cancers. Also, the data showed that HPV infection results in no increased risk of developing head and neck tumors. 相似文献