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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
81.
Koichiro Yuji Shigesaburo Miyakoshi Daisuke Kato Yuji Miura Tomohiro Myojo Naoko Murashige Yukiko Kishi Kazuhiro Kobayashi Eiji Kusumi Hiroto Narimatsu Tamae Hamaki Tomoko Matsumura Masahiro Kami Takahiro Fukuda Shigeru Masuo Kazuhiro Masuoka Atsushi Wake Junichi Ueyama Akiko Yoneyama Ko Miyamoto Haruhisa Nagoshi Michio Matsuzaki Shinichi Morinaga Yoshitomo Muto Yoichi Takeue Shuichi Taniguchi 《Biology of blood and marrow transplantation》2005,11(4):314-318
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor. 相似文献
82.
Analysis of microdissected prostate tissue with ProteinChip arrays--a way to new insights into carcinogenesis and to diagnostic tools 总被引:9,自引:0,他引:9
Wellmann A Wollscheid V Lu H Ma ZL Albers P Schütze K Rohde V Behrens P Dreschers S Ko Y Wernert N 《International journal of molecular medicine》2002,9(4):341-347
Prostate carcinomas are one of the most common malignancies in western societies. The pathogenesis of this tumor is still poorly understood. These tumors present with two characteristic features: epithelial-mesenchymal interactions, which play a pivotal role for tumor development and most of clinically manifest cancers arise in prostate proper compared to a minority of tumors which develop in the transitional zone. Deciphering the epithelial-mesenchymal cross talk and identification of molecular pecularities of the sub-populations of cells in different zones can therefore help understanding carcinogenesis and development of new, non-invasive tools for the diagnosis and prognosis of prostate carcinomas which has remained a challenge until today. A ProteinChip array technology (SELDI = surface enhanced laser desorption ionization) has been developed recently by Ciphergen Biosystems enabling analysis and profiling of complex protein mixtures from a few cells. This study describes the analysis of approximately 500-1000 freshly obtained prostate cells by SELDI-TOF-MS (surface enhanced laser desorption ionization time-of-flight mass spectrometry). Pure cell populations of stroma, epithelium and tumor cells were selected by laser assisted microdissection. Multiple specific protein patterns were reproducibly detected in the range from 1.5 to 30 kDa in 28 sub-populations of 4 tumorous prostates and 1 control. A specific 4.3 kDa peak was increased in the prostate tumor stroma compared to normal prostate proper and transitional zone stroma and increased in prostate tumor glands compared to normal prostate proper and transitional zone glands. Coupling laser assisted microdissection with SELDI provides tremendous opportunities to identify cell and tumor specific proteins to understand molecular events underlying prostate carcinoma development. It underlines the vast potential of this technology to better understand pathogenesis and identify potential candidates for new specific biomarkers in general which could help to screen for and distinguish disease entities, i.e. between clinically significant and insignificant carcinomas of the prostate. 相似文献
83.
Linkage of the MHC to familial multiple sclerosis suggests genetic heterogeneity. The Multiple Sclerosis Genetics Group 总被引:5,自引:0,他引:5
Haines JL; Terwedow HA; Burgess K; Pericak-Vance MA; Rimmler JB; Martin ER; Oksenberg JR; Lincoln R; Zhang DY; Banatao DR; Gatto N; Goodkin DE; Hauser SL 《Human molecular genetics》1998,7(8):1229-1234
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the
central nervous system. While its etiology is not well understood, genetic
factors are clearly involved. Until recently, most genetic studies in MS
have been association studies using the case-control design testing
specific candidate genes and studying only sporadic cases. The only
consistently replicated finding has been an association with the HLA-DR2
allele within the major histocompatibility complex (MHC) on chromosome 6.
Using the genetic linkage design, however, evidence for and against linkage
of the MHC to MS has been found, fostering suggestions that sporadic and
familial MS have different etiologies. Most recently, two of four genomic
screens demonstrated linkage to the MHC, although specific allelic
associations were not tested. Here, a dataset of 98 multiplex families was
studied to test for an association to the HLA-DR2 allele in familial MS and
to determine if genetic linkage to the MHC was due solely to such an
association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta)
in the MHC demonstrated strong genetic linkage (parametric lod scores of
4.60, 2.20 and 1.24, respectively) and a specific association with the
HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results
by HLA-DR2 status showed that the linkage results were limited to families
segregating HLA-DR2 alleles. These results demonstrate that genetic linkage
to the MHC can be explained by the HLA-DR2 allelic association. They also
indicate that sporadic and familial MS share a common genetic
susceptibility. In addition, preliminary calculations suggest that the MHC
explains between 17 and 62% of the genetic etiology of MS. This
heterogeneity is also supported by the minority of families showing no
linkage or association with loci within the MHC.
相似文献
84.
CTLA-4 is required for the induction of high dose oral tolerance 总被引:5,自引:3,他引:5
Samoilova EB; Horton JL; Zhang H; Khoury SJ; Weiner HL; Chen Y 《International immunology》1998,10(4):491-498
Mucosal and systemic administrations of high dose antigens induce long-
lasting peripheral T cell tolerance. We and others have shown that high
dose peripheral T cell tolerance is mediated by anergy or deletion and is
preceded by T cell activation. Co-stimulatory molecules B7-1 (CD80)/B7-2
(CD86) and their counter-receptors CD28/CTLA-4 play pivotal roles in T cell
activation and immune regulation. In the present study, we examined the
roles of the B7 co-stimulation pathway in the generation of high dose
peripheral T cell tolerance. We found that blocking B7:CD28/CTLA-4
interaction at the time of tolerance induction partially prevented T cell
tolerance, whereas selective blockade of B7:CTLA-4 interaction completely
abrogated peripheral T cell tolerance induced by either oral or i.p.
antigens. These results suggest that CTLA-4-mediated feedback regulation
plays a crucial role in the induction of high dose peripheral T cell
tolerance.
相似文献
85.
Screening for proteins with polyglutamine expansions in autosomal dominant cerebellar ataxias 总被引:2,自引:8,他引:2
Stevanin G; Trottier Y; Cancel G; Durr A; David G; Didierjean O; Burk K; Imbert G; Saudou F; Abada-Bendib M; Gourfinkel-An I; Benomar A; Abbas N; Klockgether T; Grid D; Agid Y; Mandel JL; Brice A 《Human molecular genetics》1996,5(12):1887-1892
Expansion of trinucleotide CAG repeats coding for polyglutamine has been
implicated in five neurodegenerative disorders, including spinocerebellar
ataxia (SCA) 1 and SCA3 or Machado-Joseph disease (SCA3/MJD), two forms of
type I autosomal dominant cerebellar ataxias (ADCA). Using the 1C2 antibody
which specifically recognizes large polyglutamine tracts, particularly
those that are expanded, we recently reported the detection of proteins
with pathological glutamine expansions in lymphoblasts from another form of
ADCA type I, SCA2, as well as from patients presenting with the distinct
phenotype of ADCA type II. We now have screened a large series of patients
with ADCA or isolated cases with cerebellar ataxia, for the presence of
proteins with polyglutamine expansions. A 150 kDa SCA2 protein was detected
in 16 out of 40 families with ADCA type I. This corresponds to 24% of all
ADCA type I families, which is much more frequent than SCA1 in this series
of patients (13%). The signal intensity of the SCA2 protein was negatively
correlated to age at onset, as expected for an expanded and unstable
trinucleotide repeat mutation. The disease segregated with markers closely
linked to the SCA2 locus in all identified SCA2 families. In addition, a
specific 130 kDa protein, which segregated with the disease, was detected
in lymphoblasts of patients from nine families with ADCA type II. It was
also visualized in the cerebral cortex of one of the patients,
demonstrating its translation in the nervous system. Finally, no new
disease-related proteins containing expanded polyglutamine tracts could be
detected in lymphoblasts from the remaining patients with ADCA or isolated
cases with cerebellar ataxia.
相似文献
86.
Supernumerary marker chromosomes (SMC) can be associated with both normal and abnormal phenotypes. In addition, SMC are found at higher frequency in males with infertility. We identified a SMC, characterized as a del(15)(q11.2) chromosome, in a phenotypically normal male. Using fluorescence in situ hybridization (FISH), we examined the segregation of the del(15) chromosome in sperm from this patient. Only 6.23% of sperm nuclei showed disomy using a chromosome 15 alpha-satellite FISH probe, instead of the expected 50%. In addition, FISH analysis showed no increase for non-disjunction of chromosome 18, excluding an interchromosomal effect for this chromosome. The significant decrease in sperm bearing the del(15) may be due to tissue-specific mosaicism or a result of some form of selection against the del(15) during spermatogenesis. This finding provides a basis for the observation that SMC(15) are less likely to be inherited from a paternal carrier. 相似文献
87.
Recent evidence points to the fact that osteoclasts are derived from mononuclear cells of hematopoietic bone marrow. In this study we have examined the formation of osteoclasts from mononuclear cells in vitro. The mononuclear cells were isolated after 7 days from cultures of mouse bone marrow cells. The isolated cells were co-cultured with osteoclast-free, fetal-mouse calvaria. After 10 to 14 days of co-culture, multinucleated cells which have all the characteristics of osteoclasts were found in juxtaposition to seams of woven bone. These data strongly suggest that bone marrow mononuclear cells, when suitably induced, can give rise to osteoclasts in vitro. 相似文献
88.
Tirthadipa Pradhan-Sundd Silvia Liu Sucha Singh Minakshi Poddar Sungjin Ko Aaron Bell Jonathan Franks Ian Huck Donna Stolz Udayan Apte Sarangarajan Ranganathan Kari Nejak-Bowen Satdarshan P. Monga 《The American journal of pathology》2021,191(5):885-901
Hepatocytes are highly polarized epithelia. Loss of hepatocyte polarity is associated with various liver diseases, including cholestasis. However, the molecular underpinnings of hepatocyte polarization remain poorly understood. Loss of β-catenin at adherens junctions is compensated by γ-catenin and dual loss of both catenins in double knockouts (DKOs) in mice liver leads to progressive intrahepatic cholestasis. However, the clinical relevance of this observation, and further phenotypic characterization of the phenotype, is important. Herein, simultaneous loss of β-catenin and γ-catenin was identified in a subset of liver samples from patients of progressive familial intrahepatic cholestasis and primary sclerosing cholangitis. Hepatocytes in DKO mice exhibited defects in apical-basolateral localization of polarity proteins, impaired bile canaliculi formation, and loss of microvilli. Loss of polarity in DKO livers manifested as epithelial-mesenchymal transition, increased hepatocyte proliferation, and suppression of hepatocyte differentiation, which was associated with up-regulation of transforming growth factor-β signaling and repression of hepatocyte nuclear factor 4α expression and activity. In conclusion, concomitant loss of the two catenins in the liver may play a pathogenic role in subsets of cholangiopathies. The findings also support a previously unknown role of β-catenin and γ-catenin in the maintenance of hepatocyte polarity. Improved understanding of the regulation of hepatocyte polarization processes by β-catenin and γ-catenin may potentially benefit development of new therapies for cholestasis.A hallmark of epithelial cells is polarization, which is achieved by the orchestration of external cues, such as cellular contact, extracellular matrix, signal transduction, growth factors, and spatial organization.1 Hepatocytes in the liver show a unique polarity by forming several apical and basolateral poles within a cell.2 The apical poles of adjacent hepatocytes form a continuous network of bile canaliculi into which bile is secreted, whereas the basolateral membrane domain forms the sinusoidal pole, which secretes various components, such as proteins or drugs, into the blood circulation.3 Loss of hepatic polarity has been associated with several cholestatic and developmental disorders, including progressive familial intrahepatic cholestasis (PFIC) and primary sclerosing cholangitis (PSC).4,5 Although the molecular mechanisms governing hepatocyte polarity have been extensively studied in the in vitro systems, there is still a significant gap in our understanding of how polarity is established within the context of tissue during development or maintained during homeostasis.6,7 Similarly, the molecular pathways contributing to hepatic polarity are not entirely understood, and a better comprehension of hepatic polarity regulation is thus warranted.Previous studies have confirmed the role of hepatocellular junctions, such as tight and gap junctions, in the maintenance of hepatocyte polarity.8,9 Studies done in vitro and in vivo have shown that loss of junctional proteins, such as zonula occludens protein (ZO)-1, junctional adhesion molecule-A, and claudins, lead to impairment of polarity and distorted bile canaliculi formation.10, 11, 12, 13 In addition, proteins involved in tight junction assembly, such as liver kinase B1, are also involved in polarity maintenance.14 Among adherens junction proteins, various in vitro cell culture models have confirmed the role of E-cadherin in the regulation of hepatocyte polarity, possibly through its interaction with β-catenin.15,16 However, there is a lack of an in vivo model to study the role of adherens junction proteins in hepatocyte polarity and their misexpression contributing to various liver diseases.β-Catenin plays diverse functions in the liver during development, regeneration, zonation, and tumorigenesis.17, 18, 19 The relative contribution of β-catenin as part of the adherens junction is challenging to study because like in other tissues, γ-catenin compensates for the β-catenin loss in the liver.20,21 To address this redundancy, we previously reported a hepatocyte-specific -catenin and γ-catenin double-knockout (DKO) mouse model was reported.22 Simultaneous deletion of β-catenin and γ-catenin in mice livers led to cholestasis, partially through the breach of cell-cell junctions. However, more comprehensive understanding of the molecular underpinnings of the phenotype is needed.In the current study, prior preclinical findings of dual β-catenin and γ-catenin loss were extended to a subset of PFIC and PSC patients. In vivo studies using the murine model with hepatocyte-specific dual loss of β-catenin and γ-catenin showed complete loss of hepatocyte polarity compared to the wild-type controls (CONs). Loss of polarity in DKO liver was accompanied by epithelial-mesenchymal transition (EMT), activation of transforming growth factor (TGF)-β signaling, and reduced expression of hepatocyte nuclear factor 4α (HNF4α). Our findings suggest that β-catenin and γ-catenin and in turn adherens junction integrity, are critical for the maintenance of hepatocyte polarity, and any perturbations in this process can contribute to the pathogenesis of cholestatic liver disease. 相似文献
89.
Yoshinori Seko Shigeru Ishiyama Toshiro Nishikawa Takeshi Kasajima Michiaki Hiroe Shin Suzuki Sugao Ishiwata Sachio Kawai Yuetsu Tanaka Miyuki Azuma Tetsuji Kobata Hideo Yagita Ko Okumura Ryozo Nagai 《Cardiovascular pathology》2002,11(3):166-170
BACKGROUND: T-cell-mediated myocardial damage is known to be involved in acute myocarditis and dilated cardiomyopathy. Recently, we found that tumor necrosis factor (TNF) ligand superfamily costimulatory molecules, especially 4-1BBL, played an important role in the myocardial damage of murine acute viral myocarditis. METHODS AND RESULTS: To investigate the roles for CD27L, CD30L, OX40L and 4-1BBL, which belong to TNF ligand superfamily, in the development of acute myocarditis and dilated cardiomyopathy, we analyzed the expression of these antigens in the myocardial tissues of patients with acute myocarditis and dilated cardiomyopathy. We also examined expression of the receptors for these molecules, CD27, CD30, OX40 and 4-1BB, which belong to TNF receptor superfamily, on the infiltrating cells. Strong expression of CD27L, CD30L and 4-1BBL and weak to moderate expression of OX40L was found in the cardiac myocytes of patients with acute myocarditis. Moderate expression of CD27L, CD30L and 4-1BBL and weak expression of OX40L was found on the cardiac myocytes of patients with dilated cardiomyopathy. Most of the infiltrating cells expressed CD27, CD30 and 4-1BB and a part of the infiltrating cells expressed OX40. CONCLUSIONS: Our findings suggest that expression of TNF ligand superfamily costimulatory molecules on cardiac myocytes may play a role in the cell-mediated myocardial damage in patients with acute myocarditis and dilated cardiomyopathy as in murine viral myocarditis. 相似文献
90.
F. W. S. Ko H. Y. Wang† G. W. K. Wong‡ T. F. Leung‡ D. S. C. Hui D. P. S. Chan N. S. Zhong† C. K.W. Lai 《Clinical and experimental allergy》2005,35(11):1449-1456
BACKGROUND: Asthma is a common chronic disease and information on its management practices at the community level is helpful in identifying problems and improving asthma care. OBJECTIVE: To assess the severity status and management of the asthma symptom of wheeze of children at the community level in Hong Kong (HK) and Guangzhou (GZ). METHODS: Cross-sectional study of children aged 10 years using the International Study of Asthma and Allergic disease in Childhood (ISAAC Phase II protocol). Asthma management and lung function were assessed in 178 (98 from HK and 80 from GZ) randomly selected children with wheeze over the past 12 months. RESULTS: Eighty-three percent, 11%, 6% and 0% of children suffered from intermittent, mild persistent, moderate persistent and severe persistent asthma, respectively, according to the frequency of their symptoms. Addition of spirometric parameter only changed the asthma severity classification in 2.8% of children. Medications were used by 30.6% and 71.3% of children for wheeze in HK and GZ, respectively. In HK, inhaled beta(2)-agonist (73.3% among the drug users) was the commonest medication used followed by inhaled corticosteroid (ICS) (23.3%). In GZ, inhaled beta(2)-agonist was used by 75.4% of children, but use of ICS (26.3%), oral beta(2)-agonist (26.3%), oral theophylline (45.6%), oral ketotifen (36.8%) and oral steroid (35.1%) were also common. ICS was only used by 11.4% of children with persistent asthma. Ten percent and 18.7% of children in HK and GZ, respectively, had emergency department visits, while 16.3% and 11.6% of children in HK and GZ, respectively, had missed school secondary to asthma over the past 1 year. CONCLUSIONS: Most children in the community had intermittent asthma and addition of lung function to symptoms did not significantly affect classification of asthma severity. Significant morbidity was seen even in this group of children with mostly intermittent and mild persistent asthma. 相似文献