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991.
Nae Yu Kim Jung-Soo Pyo Dong-Wook Kang Seung-Min Yoo 《Pathology, research and practice》2019,215(3):580-585
Objective
The aim of this study was to elucidate the clinicopathological significance and prognostic role of loss of claudin-1 in colorectal cancer (CRC).Methods
The correlations between claudin-1 expression and clinicopathological characteristics, including survival rates, were assessed using immunohistochemistry on 260 archival, paraffin-embedded CRC tissues. In addition, the correlations between cludin-1 and nuclear factor-kappa B (NF-κB), epithelial-mesenchymal transition markers and tumor-infiltrating lymphocytes were investigated.Results
Claudin-1 expression was markedly lost in 42.7% of the 260 CRCs analyzed. Loss of claudin-1 expression significantly correlated with larger tumor size, vascular invasion, higher pT stage, and high metastatic lymph node ratio. In addition, loss of claudin-1 expression significantly correlated with NF-κB activation (P?<?0.001), high SNAI (P?<?0.001), and low E-cadherin (P?<?0.001) expressions. Patients with high immunoscores showed significantly lower rates of claudin-1 expression loss (P?=?0.020). In detail, loss of claudin-1 expression were frequently found in CRCs low CD3- and CD8-positive lymphocytes. There were significant correlations between claudin-1 expression loss and poor overall and recurrence-free survivals (P?<?0.001 and P?<?0.001, respectively).Conclusion
Taken together, our results suggest that the loss of claudin-1 expression significantly correlates with aggressive tumor behaviors, high SNAI expression, lower immunoscore, and poor prognoses. 相似文献992.
IMMUNOHISTOCHEMICAL DISTRIBUTION OF CANNABINOID CB 1 RECEPTOR IN THE RAT CENTRAL NERVOUS SYSTEM@邹冈 相似文献
993.
Susceptibility to clinically manifest cyclosporine A (CsA)-induced autoimmune disease is associated with interferon-gamma (IFN-γ)-producing CD45RC+RT6− T helper cells 下载免费PDF全文
L J J BEIJLEVELD H GROEN C P M BROEREN F A KLATTER J KAMPINGA J G M C DAMOISEAUX P J C VAN BREDA VRIESMAN 《Clinical and experimental immunology》1996,105(3):486-496
Lethally irradiated Lewis (LEW) rats reconstituted with syngeneic bone marrow and given CsA for a 4-week period, develop, upon withdrawal of CsA, a graft-versus-host-like disease, so-called CsA-induced autoimmunity (CsA-AI). This T cell-mediated autoimmune disease is thymus-dependent; it is generally held that this disease is a consequence of aberrant T cell recovery brought about by CsA. In this study we determined mononuclear cell subsets phenotypically by tri-colour flow cytometry. A strong decrease in recent thymic emigrants (Thy1.1+, TCR αβ+) was observed as a consequence of CsA treatment, eventually resulting in decreased absolute peripheral T cell numbers. In these rats no altered CD4:CD8 T cell ratio was observed before onset of CsA-AI; CD4+ and CD8+ cells consisted predominantly of monocytes (CD4dim+, TCR αβ−) and natural killer cells (CD8+, TCR αβ−), respectively. LEW rats, x-irradiated, syngeneic bone marrow-reconstituted and treated with CsA, showed a marked and persistent, relative expansion of mature CD45RC+, RT6− Th cells. In contrast, Brown-Norway rats treated in a similar fashion, or LEW rats subjected to either CsA treatment or x-irradiation, did not show a comparable expansion of mature CD45RC+, RT6− Th cells, nor did these animals develop CsA-AI. The CD45RC+, RT6− Th cells produced IL-2, and moreover constituted the only Th subset producing IFN-γ upon stimulation, and therefore were considered as Th1-like effector cells. These results are consistent with the view that a persistent preponderance of Th1 cells and not the mere presence of autoreactive cells determines whether or not clinically manifest CsA-AI will occur. 相似文献
994.
Brooks TD Slomp J Quax PH De Bart AC Spencer MT Verheijen JH Charlton PA 《Clinical & experimental metastasis》2000,18(6):445-453
Recent reports suggest that elevated levels of plasminogen activator inhibitor-1 (PAI-1) may contribute to tumour progression.
The studies reported here were designed to help elucidate PAI-1's contribution to the invasive and migratory phenotype. Antibodies
to PAI-1 dose-dependently, and significantly, inhibited the invasive and migratory potential of human HT1080 fibrosarcoma
cells, as did an antibody to uPA and the plasmin inhibitor aprotinin. Invasion of the human melanoma cell line, BLM, was also
attenuated by the anti-PAI-1 monoclonal antibody MAI-12. The non-invasive human melanoma cell line, IF6, which does not express
uPA, provided further confirmation of PAI-1 and uPA's role as, upon transfection with uPA, this cell line attained an invasive
phenotype, which was again attenuated by MAI- 12. Although antibodies to PAI-1 did not affect the adhesion of HT1080 cells
to vitronectin, the antibody to uPA reduced their attachment. Addition of exogenous PAI-1, however, prevented HT1080 cell
adhesion (IC50 180nM) and promoted cell detachment from vitronectin. Furthermore melanoma cells transfected with a uPA variant, which had
an impaired interaction with PAI-1, were not invasive and had impaired binding to vitronectin. These data highlight the importance
of a balanced proteolysis and suggest an additional role for PAI-1 distinct from its role in proteolysis. These data also
suggest that uPA and PAI-1 may co-operate in the migratory process by respectively facilitating the attachment to, and subsequent
detachment from, vitronectin in the extracellular matrix. These results support the clinical findings and indicate that modulation
of PAI-1 activity may be of therapeutic benefit for the treatment of cancer.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
995.
996.
以体外培养的猪主动脉内皮细胞(EC)为模型研究Ilopost对EC抗血栓功能的影响。用放免法、发色底物法测定培养液中6-酮-PGF1α(6-keto-PGF1α),血栓素B2(TXB2)含量,纤溶酶原激活物(PA),纤溶酶原激活物抑制物(PAI)活性及EC环磷酸腺苷(cAMP)含量。结果表明:Iloprost中以使EC生成6-keto-PGF1α,cAMP含量显著增多,TXB2含量显著减少,并使P 相似文献
997.
Male wild (Cavia aperea) and domestic (C. porcellus) guinea pigs were tested in two-bottle choice tests for preferences between glucose solutions of different concentrations and de-ionized water. Wild males showed significant preferences for concentrations between 0.025 and 0.4 M glucose while domestic males preferred only the 0.2 M glucose solution to de-ionized water. C. aperea males also consumed significantly greater volumes of liquid per kg body during the glucose tests than did the C. porcellus males. These comparative results contrast sharply with those obtained by other authors with wild and domestic Norway rats. 相似文献
998.
Masaharu Muranaka Shuji Suzuki Kazuhiro Koizumi Hiroshi Igarashi Hiroshi Okumura Koyo Takeda Kenji Tadokoro Yoshihiko Horiuchi 《The Journal of allergy and clinical immunology》1978,62(5):276-282
All of the five commercially available benzylpenicillin preparations obtained from different sources and a PcG preparation prepared by filtration of a commercial PcG on Sephadex G10 elicited the systemic anaphylactic reactions in guinea pigs which had been immunized with benzylpenicilloyl (BPO)-Ascaris extract conjugate (BPO-As) mixed with aluminum hydroxide gel. These preparations could evoke no such reactions in guinea pigs immunized with BPO-bovine gamma globulin conjugate (BPO-BGG) emulsified with complete Freund's adjuvant. The severity of the systemic anaphylactic reactions correlated significantly with the titers of either 8-day passive cutaneous anaphylactic (8-day PCA) reactions or 4-hr PCA reactions evoked with the same benzylpenicillin preparations. In vitro benzylpenicillin preparation contracted the tracheas of the guinea pigs immunized with BPO-As. These results indicated that the commercially available benzylpenicillin preparations have enough antigenicity to evoke systemic anaphylactic reactions in guinea pigs immunized with BPO-As mixed with aluminum hydroxide gel. Such guinea pigs represent an animal model for investigation of penicillin allergy. 相似文献
999.
M. Vandenbranden J.L. de Coen R. Jeener L. Kanarek J.M. Ruyschaert 《Molecular immunology》1981,18(7):621-631
Interactions between rabbit-γ-immunoglobulins and model membranes (lipid monalayers, planar lipid bilayers, liposomes) have been investigated. No significant interaction was observed with immunoglobulins. However, immunoglobulins dialysed first vs aqueous buffer having pH 2 or 3 and then dialysed against pH 7 buffer presumably adopt a new conformation which allows their bindings to model membranes. This binding is hydrophobic and the immunoglobulin region interacting with the lipid acyl chains is probably located in the heavy chain, as suggested by labelling in this region by a photosensitive probe previously incorporated into the lipid hydrophobic core. Cleavage at the hinge region by papain or pepsin, or heating above 38°C, induces the loss of the hydrophobic conformation responsible for hydrophobic bindings. The binding capacity of immunoglobulins heated above 38°C is restored after momentary dialysis at pH 2. The possible existence of two Ig isomers is discussed in relation to the mechanism of γ-immunoglobulin passage through the endoplasmic membrane and fixation into the plasma membrane. 相似文献
1000.
Mohammad M. Al‐Qattan Fowzan S. Alkuraya 《American journal of medical genetics. Part A》2019,179(2):266-279
Cenani–Lenz (C–L) syndrome is characterized by oligosyndactyly, metacarpal synostosis, phalangeal disorganization, and other variable facial and systemic features. Most cases are caused by homozygous and compound heterozygous missense and splice mutations of the LRP4 gene. Currently, the syndrome carries one OMIM number (212780). However, C–L syndrome‐like phenotypes as well as other syndactyly disorders with or without metacarpal synostosis/phalangeal disorganization are also known to be associated with specific LRP4 mutations, adenomatous polyposis coli (APC) truncating mutations, genomic rearrangements of the GREM1‐FMN1 locus, as well as FMN1 mutations. Surprisingly, patients with C–L syndrome‐like phenotype caused by APC truncating mutations have no polyposis despite the increased levels of β catenin. The LRP4 and APC proteins act on the WNT (wingless‐type integration site family) canonical pathway, whereas the GREM‐1 and FMN1 proteins act on the bone morphogenetic protein (BMP) pathway. In this review, we discuss the different mutations associated with C–L syndrome, classify its clinical features, review familial adenomatous polyposis caused by truncating APC mutations and compare these mutations to the splicing APC mutation associated with syndactyly, and finally, explore the pathophysiology through a review of the cross talks between the WNT canonical and the BMP antagonistic pathways. 相似文献