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91.
Apoptosis or programmed cell death (PCD) is an active process of cellular self-destruction, essential for embryonic development and maintenance of homeostasis of multicellular organisms. Programmed cell death induction can serve as a defence mechanism of the host against intracellular microbes. Virus infections trigger host cell apoptosis, which can either limit virus production or contribute directly to viral pathogenesis.Several independent laboratories have identified "tissue" transglutaminase (tTG) as a potentially important player of the cell death program(s). This gene is specifically expressed in cells dying during mammalian development as well as in those undergoing apoptosis in various patho-physiological and experimental settings [Eur. J. Cell Biol. 56 (1991) 170; Piacentini, M., Davies, P.J.A., Fesus, L., 1994. Tissue transglutaminase in cells undergoing apoptosis. In: Tomei, L.D., Cope, F.O. (Eds.), Apoptosis II: The molecular basis of apoptosis in disease. Cold Spring Harbor Lab. Press, pp. 143-165.]. This chapter reviews recent studies concerning the expression and the possible role of "tissue" transglutaminase (tTG) in apoptotic cells; particular emphasis is given to its expression in the cell death pathways associated with HIV infection in the immune system.We propose here that the induction of the tTG gene in cells of the immune system, as well as the detection of the isodipeptide epsilon(gamma-glutamyl)lysine in plasma, are useful markers of apoptosis and might make it possible to monitor disease progression in HIV-infected individuals. 相似文献
92.
Mauro S. Sandrin Ian F. C. McKenzie Roger W. Melvold Günter J. Hmmerling 《European journal of immunology》1982,12(3):205-209
The B6.C-H-2bm12 has been examined serologically with a new set of reagents and several complementation studies were performed to determine the extent of the mutation. The results show that: (a) the mutation has also affected the site(s) bound by xenogeneic anti-Ia antibodies; (b) the IJb region was not affected; (c) complementation studies with stains bearing a, b, d, k and s haplotypes did not complement bm12 for the expression of the lost I-Ab specificities, suggesting a structural (rather than regulatory) gene alteration in bm12; (d) H-2 haplotypes b and bm12 could complement d to establish the Ia.22 specificity, indicating that Ia-1 and Ae are separate genes in the I-A subregion. In addition, an antibody to the gained specificity on bm12 is described. 相似文献
93.
Selmi C Ichiki Y Invernizzi P Podda M Gershwin ME 《Clinical reviews in allergy & immunology》2005,28(2):73-81
Primary biliary cirrhosis (PBC) is a chronic cholestatic disease characterized by a striking predominance in female patients
(with most cases diagnosed between ages 40 and 60 yr) as well as serum auto-antibodies to mitochondrial antigens, elevated
serum immunoglobulin M, progressive destruction of intrahepatic bile ducts, and, ultimately, liver cirrhosis and failure (1). The precise mechanisms leading to selective destruction of biliary epithelial cells lining intrahepatic bile ducts are
still unknown, although numerous immunomediated pathways have been proposed. Genetic background appears to be important in
determining susceptibility to the disease (2), but no clear association with alleles in the major histocompatibility complex has been identified. Molecular mimicry either
by infections (3) or xenobiotics (4) has been proposed to be capable of breaking tolerance in genetically predisposed individuals, thus leading to onset of PBC.
This article describes and discusses the available data regarding the immunomediated pathogenesis of PBC (with particular
attention to auto-antibodies and autoreactive T-cells) and presents the recent evidence indicating a role for either xenobiotic
chemicals or novel infectious agents in the induction of the disease. 相似文献
94.
Platelet-activating factor receptor deficiency delays elimination of adult worms but reduces fecundity in Strongyloides venezuelensis-infected mice 总被引:2,自引:0,他引:2
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Negrão-Corrêa D Souza DG Pinho V Barsante MM Souza AL Teixeira MM 《Infection and immunity》2004,72(2):1135-1142
We describe the parasitological kinetics and histopathological and immunological alterations in platelet-activating factor receptor-deficient (PAFR(-/-)) and wild-type mice after a single Strongyloides venezuelensis infection (subcutaneous inoculation of 500 L3 larvae). There was no difference in the numbers of worms that reached and became established in the small intestines of PAFR(-/-) and wild-type mice. However, at 12 days after infection, significantly more worms were recovered from PAFR(-/-) mice. Although PAFR(-/-) infected mice showed a delay in elimination of adult worms, worms established in the small intestine of these mice produced a significantly lower number of eggs due to a reduction in worm fecundity. There were also significant reductions in the number of circulating and tissue eosinophils and tumor necrosis factor levels in the small intestines of PAFR(-/-) mice infected for 7 days compared to the number and level in wild-type mice. Histological analysis confirmed the reduced inflammatory process and revealed that the PAFR(-/-) mice had a smaller number of goblet cells. The concentrations of the type 2 cytokines interleukin-4 (IL-4), IL-5, and IL-10 were lower in small intestine homogenates and in supernatants of antigen-stimulated lymphocytes from spleens or mesenteric lymph nodes of PAFR(-/-) mice than in the corresponding preparations from wild-type mice. Thus, in S. venezuelensis-infected PAFR(-/-) mice, decreased intestinal inflammation is associated with enhanced worm survival but decreased fecundity. We suggest that although a Th2-predominant inflammatory response decreases worm survival, the worm may use factors produced during this response to facilitate egg output and reproduction. PAFR-mediated responses appear to modulate these host-derived signals that are important for worm fecundity. 相似文献
95.
Paola Vigan Ruggero Pardi Barbara Magri Mauro Busacca Anna Maria Di Blasio Mario Vignali 《American journal of reproductive immunology (New York, N.Y. : 1989)》1994,32(3):139-145
PROBLEM: Recent evidence emphasizes the role of natural killer cells (NKs) as potential effectors of peritoneal immune surveillance directed against the outgrowth of endometrial cells, refluxed with menstrual debris, in ectopic sites. This NK-mediated cytotoxicity toward autologous endometrial antigens seems to be significantly decreased in endometriosis patients. METHOD: We set up experiments to clarify which molecules are involved in NK-endome-trial cell interaction. In particular, we evaluated the surface expression and functional activity of intercellular adhesion molecule-1 (ICAM-1), a cell surface glycoprotein that has been identified as one of the ligands for lymphocyte function-associated antigen-1 (LFA-1), present on almost all leucocyte cell types. Immunofluorescence flow cytometry was used to assess ICAM-1 expression on resting and IL 1β-activated endometrial stromal cells in culture. Dermal fibroblasts were used as control cells. Cytotoxicity and binding assays by 51Cr release in presence and absence of a specific monoclonal antibody (mAb) against ICAM-1 were then performed in order to determine the effect of this molecule on NK-mediated cytotoxic and binding activity toward endometrial stromal cells. RESULTS: The results of this study indicated that ICAM-1 expression on endometrial stromal cells seems to be constitutively higher than on dermal fibroblasts and can be up-regulated upon exposure to IL 1β. Furthermore, a mAb against ICAM-1 strongly inhibits the binding but not the cytotoxicity of NKs toward endometrial cells. No difference in the expression of this molecule was observed throughout the cycle. CONCLUSIONS: The presence of ICAM-1 on human endometrium might relate to the action of the immunocompetent cells in human specific reproductive events. 相似文献
96.
Mauro Congia Fulvia Frau Rosanna Lampis Rita Frau Roberto Mele Francesco Cucca Francesco Muntoni Susanna Porcu Francesca Boi Licinio Contu Giorgio La Nasa Marina Mulargia Mario Pirastu Antonio Cao Stefano De Virgillis 《Tissue antigens》1992,39(2):78-83
This study characterizes by serological and molecular methods the HLA class I and class II alleles in a group of celiac disease children, their parents and a control group of Sardinian descent. We found the DR3-DQw2 haplotype in all patients which was, in almost all cases (84%), associated with the HLA-A30, B18, DR3, DRw52, DQw2 extended haplotype named "Sardinian haplotype" because of its frequency (12-15%) in this Caucasian population. This is the first time that this DQw2-linked haplotype has been reported with such a high frequency in CD. However, no different distribution of "Sardinian haplotype" was found comparing CD patients with 91 haplotyped DQw2-positive controls. This finding indicates that the DQw2 antigen in Sardinians is almost always associated with the A30, B18, DR3, DRw52, DQw2 extended haplotype. The DQA1 and DQB1 second exon sequence analysis of the B18,DR3 and B8,DR3 haplotypes showed the DQA1*0501 and DQB1*0201 alleles which shared the already published sequences. DPB1 subtyping showed the DPB1*0301 allele more frequently (p less than 0.005) in CD patients but this difference was no longer significant when patients and controls, both heterozygous for the DR3-DQw2 haplotype, were compared. We suggest that the divergent HLA extended haplotypes and DP allele associated with CD, described in different Caucasian populations, can be explained by the particular DQw2 linkage disequilibrium in each population. 相似文献
97.
Rosa C. Villegas-Valle Unhee Lim Gertraud Maskarinec Adrian A. Franke Thomas Ernst Bo Fan Gerardo Álvarez-Hernández Maria del Carmen Candia-Plata Rolando Giovanni Díaz-Zavala Lynne R. Wilkens Kristine R. Monroe Mauro E. Valencia Loïc Le Marchand John A. Shepherd 《Obesity research & clinical practice》2021,15(3):227-234
ObjectiveTo determine if visceral adipose tissue (VAT) area measured through MRI can be used opportunistically to assess the presence of cardiometabolic risk factors and compare its performance to simpler adiposity measures.MethodsA cross-sectional analysis was carried out on a subset of 1683 participants (856 women) from the Adiposity Phenotype Study (mean age = 69.2y; range 59.9–77.4). The association of total VAT area (sum of four cross sections, L1–L2, L2–L3, L3–L4, L4–L5) and each location, as well as BMI and body fat % (per SD) with the metabolic syndrome (MetSx) or its components was evaluated through logistic regression analysis.ResultsTotal VAT can be accurately predicted using all sites evaluated (R2 range = 0.82?0.96). In men, VAT did not show a superior association to MetSx compared to BMI in men. However, in women, VAT was consistently superior to BMI and body fat % in its association to MetSx, independent of ethnicity [odds ratio for BMI, body fat %and total VAT area = 2.25 (95% CI: 1.93–2.62); 1.66 (95% CI: 1.36–2.03); 6.20 (95% CI: 4.69–8.21) respectively in all women]. Ethnic-specific odds ratios to MetSx in women ranged from 5.38 to 8.63 for total VAT area and 2.12–4.08 for BMI.ConclusionTotal VAT area can be accurately predicted from individual VAT regions in men and women and offers superior association to BMI for MetSx in women but not in men for five ethnicities. Therefore, opportunistic screening for elevated VAT area in women may be warranted across multiple ethnic groups. 相似文献
98.
Andrea P. Rossi Cesare Caliari Silvia Urbani Francesco Fantin Piero Brandimarte Angela Martini Elena Zoico Giulia Zoso Alessio Babbanini Alfredo Zanotelli Mauro Zamboni 《Nutrients》2021,13(2)
Background: SARC-F and Mini Sarcopenia Risk Assessment (MSRA) questionnaires have been proposed as screening tools to identify patients at risk of sarcopenia. The aim of this study is to test the use of SARC-F and MSRA, alone and combined, as a pre-screening tool for sarcopenia in geriatric inpatients. Methods: 152 subjects, 94 men and 58 women, aged 70 to 94, underwent muscle mass evaluation by dual energy X-ray absorptiometry (DXA), muscle strength evaluation by handgrip, and completed the MSRA, SARC-F and Activity of daily living (ADL) questionnaires. Results: 66 subjects (43.4%) were classified as sarcopenic according to the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) criteria. The 7-item SARC-F and MRSA and 5-item MSRA showed an area under the curve (AUC) of 0.666 (95% confidence interval (CI): 0.542–0.789), 0.730 (95% CI: 0.617–0.842) and 0.710 (95% CI: 0.593–0.827), respectively. The optimal cut-off points for sarcopenia detection were determined for each questionnaire using the Youden index method. The newly calculated cut-off points were ≤25 and ≤40 for MSRA 7- and 5-items, respectively. The ideal cut-off for the SARC-F was a score ≥3. Applying this new cut-off in our study population, sensitivity and specificity of the 7-item MSRA were 0.757 and 0.651, and 0.688 and 0.679 for the 5-item MSRA, respectively. Sensitivity and specificity of SARC-F were 0.524 and 0.765, respectively. The combined use of the 7-item SARC-F and MSRA improved the accuracy in sarcopenia diagnosis, with a specificity and sensitivity of 1.00 and 0.636. Conclusion: 7-item SARC-F and MSRA may be co-administered in hospital wards as an easy, feasible, first-line tool to identify sarcopenic subjects. 相似文献
99.
Di Rienzo Alessandro Colasanti Roberto Gladi Maurizio Dobran Mauro Della Costanza Martina Capece Mara Veccia Salvatore Iacoangeli Maurizio 《Neurosurgical review》2021,44(3):1523-1532
Neurosurgical Review - The optimal management of cranioplasty infections remains a matter of debate. Most authors have suggested that the infected bone/implant removal is mandatory, combined with... 相似文献
100.
Antonio M. Calafiore Antonio Totaro Nicola Testa Cosimo Sacra Gaetano Castellano Stefano Guarracini Massimo Di Marco Sotirios Prapas Mario Gaudino Roberto Lorusso Domenico Paparella Michele Di Mauro 《Journal of cardiac surgery》2021,36(1):247-259
In secondary mitral regurgitation, the concept that the mitral valve (MV) is an innocent bystander, has been challenged by many studies in the last decades. The MV is a living structure with intrinsic plasticity that reacts to changes in stretch or in mechanical stress activating biohumoral mechanisms that have, as purpose, the adaptation of the valve to the new environment. If the adaptation is balanced, the leaflets increase both surface and length and the chordae tendineae lengthen: the result is a valve with different characteristics, but able to avoid or to limit the regurgitation. However, if the adaptation is unbalanced, the leaflets and the chords do not change their size, but become stiffer and rigid, with moderate or severe regurgitation. These changes are mediated mainly by a cytokine, the transforming growth factor‐β (TGF‐β), which is able to promote the changes that the MV needs to adapt to a new hemodynamic environment. In general, mild TGF‐β activation facilitates leaflet growth, excessive TGF‐β activation, as after myocardial infarction, results in profibrotic changes in the leaflets, with increased thickness and stiffness. The MV is then a plastic organism, that reacts to the external stimuli, trying to maintain its physiologic integrity. This review has the goal to unveil the secret life of the MV, to understand which stimuli can trigger its plasticity, and to explain why the equation “large heart = moderate/severe mitral regurgitation” and “small heart = no/mild mitral regurgitation” does not work into the clinical practice. 相似文献