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21.
22.
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
23.
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
24.
Amills M Sulas C Sànchez A Bertoni G Zanoni R Obexer-Ruff G 《Molecular immunology》2005,42(3):375-379
The major histocompatibility class II DQ molecules are dimeric glycoproteins involved in antigen presentation to CD4(+) T cells. In the current work, we have performed the molecular analysis of the goat Cahi-DQA1 gene. Sequencing of the Cahi-DQA1 cDNA revealed a single 768bp open reading frame. The alignment of this sequence with its bovine and ovine DQA1 counterparts revealed a remarkable degree of nucleotide identity (92-93% for the most similar bovine and ovine sequences). Moreover, we amplified a region including the 3'-end of intron 1, exon 2 and the 5'-end of intron 2. We identified seven Cahi-DQA1 alleles that likely correspond to four different allelic lineages. The alignment of these seven Cahi-DQA1 alleles revealed the existence of 23 amino acid polymorphic sites, seven of which (alpha(10), alpha(55), alpha(56), alpha(68), alpha(69), alpha(71) and alpha(76)) are highly polymorphic with at least three amino acid substitutions. Ten of the 23 polymorphic amino acid sites were included in the peptide binding region and consequently they might play a crucial role in immunological processes modulating disease pathogenesis. 相似文献
25.
Biomarkers for neurodegenerative diseases should reflect the central pathogenic processes of the diseases. The field of clinical proteomics is especially well suited for discovery of biomarkers in cerebrospinal fluid (CSF), which reflects the proteins in the brain under healthy conditions as well as in several neurodegenerative diseases. Known proteins involved in the pathology of neurodegenerative diseases are, respectively, normal tau protein, beta-amyloid (1-42), synaptic proteins, amyloid precursor protein (APP), apolipoprotein E (apoE), which previously have been studied by protein immunoassays. The objective of this paper was to summarize results from proteomic studies of differential protein patterns in neurodegenerative diseases with focus on Alzheimer's disease (AD). Today, discrimination of AD from controls and from other neurological diseases has been improved by simultaneous analysis of both beta-amyloid (1-42), total-tau, and phosphorylated tau, where a combination of low levels of CSF-beta-amyloid 1-42 and high levels of CSF-tau and CSF-phospho-tau is associated with an AD diagnosis. Detection of new biomarkers will further strengthen diagnosis and provide useful information in drug trials. The combination of immunoassays and proteomic methods show that the CSF proteins express differential protein patterns in AD, FTD, and PD patients, which reflect divergent underlying pathophysiological mechanisms and neuropathological changes in these diseases. 相似文献
26.
H. W. Pia 《Acta neurochirurgica》1985,77(3-4):81-102
Summary Cerebral plasticity constitutes one of the most decisive factors in recovery and readaptation after cerebral lesions. In contrast to the considerable progress in current studies on normal neuronal plasticity including the idea of l'homme neuronal, the concept of plasticity postulated by Albrecht Bethe in 1929 received little attention. The author, as a neurosurgeon, has tried to describe cranial morphological plasticity, morphological and functional plasticity in infantile encephalopathies and especially in hemiatrophic lesions. It is supposed that a true morphological substrate exists due to compensatory hyperplasia of the uninvolved hemisphere.Modern neurosurgical techniques have demonstrated that the functional plastic capacity is much larger than has been supposed, even in the elderly. Some aspects of the mechanisms of compensation and decompensation of cortical and subcortical structures as well as of the central regulation systems are discussed. The full extent of the amazing recovery and functional reorganization is reached by plastic capacity, personal motivation, adequate training and sufficient time.The contribution ends with an exposition of a personal philosophy concerning psycho-somatic dualism, the body-mind problem, the future of the human brain and the ethical outlook, based on the progressive biological evolution of the basal neocortex and the immanent functional development (H. Spatz).In grateful memory of my paternal friends, the great German brain researchers Julius Hallervorden (1882–1965) and Hugo Spatz (1888–1969). 相似文献
27.
H. W. Pia 《Acta neurochirurgica》1986,82(1-2):1-6
Summary Following the research of Giessen Neurosurgery on primary and secondary lesions of the hypothalamo-pituitary system and the brainstem over a period of more than 30 years, cerebral failure and death does not represent a uniform syndrome but consists of several, well characterized syndromes of irreversible hypothalamo-pituitary, mesencephalic and bulbar failure. The specific syndromes are described in detail. The diagnosis is based on establishing complete irreversible damage of specific vital basal functions such as hypothalamo-pituitary transmission, water-and electrolyte metabolism, temperature regulation, circulation and respiration. The common feature of all types is the irreversible break-down of the complex central neurogenous and/or neurohumoral regulatory system. The permanent and irreversible loss of central regulation and modulation means at the same time the complete cessation of the specific human cortical function, the death of the whole brain. Only in bulbar failure with primary irreversible cessation of respiration artificial respiration can maintain the autonomous functions of the heart for a limited time. It is indicated when organ explantation is to be considered. Complete and irreversible isolated loss of cortical function abolishes the normal human life, but does not mean death of the remaining vegetating human being.Presented at the meeting of the Working Group of the Pontificia Academia Scientiarum on The artificial prolongation of life and the exact determination of the moment of death, Vatican City, October 19–21, 1985.Dedicated to Prof. Dr. Jean Brihaye at the occasion of his 65th anniversary. 相似文献
28.
Cannizzaro Delia Tropeano Maria Pia Milani Davide Spaggiari Riccardo Zaed Ismail Mancarella Cristina Lasio Giovanni Battista Fornari Maurizio Servadei Franco Cardia Andrea 《Neurosurgical review》2021,44(3):1217-1225
Neurosurgical Review - Chordoma is a rare slow-growing neoplastic bone lesion. However, they show an invasive local growth and high recurrence rate, leading to an overall survival rate of 65% at 5... 相似文献
29.
Wolf Rasmus Trap Ratcliffe Julie Chen Gang Jeppesen Pia 《Quality of life research》2021,30(6):1747-1756
Quality of Life Research - The Child Health Utility 9D (CHU9D) currently represents the only preference-based health-related quality-of-life instrument designed exclusively from its inception for... 相似文献
30.
The Authors described a particular ultrasound finding which can sometimes be observed in the echographic picture of diffused hepatic steatosis and which was seen by these Authors in 117 out of 312 patients affected by steatosis. This finding consists of the presence of one or more hypoechoic focal areas situated at the IV-V and/or II-III segment level surrounded by wide-spread increase in echogenicity of remaining parenchyma, which is typical of "bright liver". These areas, which can easily be mistaken for neoplastic formations, were instead seen to be limited areas of normal liver parenchyma free of fatty infiltration. In those patients presenting valid reasons for suspecting the presence of primary or secondary neoplastic formations, the Authors believe that echographic examination of these areas should always be accompanied by more invasive methods in order to confirm or exclude the possible presence of neoplastic formations with certainty. On the contrary, in those patients where no such diagnosis is suspected, it should prove sufficient to monitor these ares by means of ultrasound. 相似文献