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41.
Susceptibility or resistance to infection with Leishmania major correlates with the ability of mice to produce characteristic panels of lymphokines in response to the parasite. To investigate the role of antigen-presenting cells in this phenomenon, we developed a model system which used congenic (H-2d) susceptible and resistant mice. L. major-specific T cells were isolated from infected BALB/c and B10.D2 mice, and the cells were restimulated in vitro on syngenic or congenic antigen-presenting cells. BALB/c L. major-reactive T cells restimulated with either antigen-presenting cell produced high levels of interleukin-4 and low levels of gamma interferon. In contrast, T cells from B10.D2 mice produced gamma interferon. Radiation-induced chimeras reconstituted with BALB/c bone marrow also produced more interleukin-4 in response to L. major than did chimeras reconstituted with B10.D2 bone marrow. To test whether this pattern of cytokine secretion was unique to infection with L. major, we infected the mice with a second intracellular pathogen, Mycobacterium bovis BCG. Mycobacterium-specific T cells from both BALB/c and B10.D2 mice produced interleukin-2 and no interleukin-4. Finally, when BALB/c mice were vaccinated with avirulent L. major, the induced resistance correlated with reduced production of interleukin-4 but no increase in gamma interferon production. Instead, T cells from the vaccinated mice produced high levels of tumor necrosis factor. This suggests that tumor necrosis factor, in addition to gamma interferon, may be involved in resistance to L. major and that interleukin-4 may inhibit the leishmanicidal activity of tumor necrosis factor and/or gamma interferon.  相似文献   
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Journal of Public Health - Screening services for early detection of patients is one of the important capabilities of the health system with a proper referral system. In the crisis of respiratory...  相似文献   
43.
Testicular torsion/detorsion is one of the important emergencies that requires fast surgical intervention. This study aimed to investigate the effects of Salvia miltiorrhiza hydroalcoholic extract combined with verapamil on testicular ischaemia/reperfusion damage in Wistar albino rats. All animals were distributed in 3 groups (n = 8), including the sham-operated group, torsion/detorsion (TD) group and torsion/detorsion + pretreatment with 200 mg/kg Salvia miltiorrhiza extract combined with 0.3 mg/kg verapamil (SMV) group. Oxidative stress biomarkers (MDA, GPx, CAT and TAC) both in plasma and testicular tissue, sperm parameters (motility, vitality, concentration and morphology) and histopathological parameters (MSTD, GECT, Johnson's score, Cosentino's score and testicular cell thickness) were assessed in all groups. Ischaemia/reperfusion significantly increased MDA and decreased GPx, CAT and TAC levels (p < .05). Pretreatment with SMV significantly increased GPx, CAT and TAC levels (p < .05). SMV group increased progressive sperm motility and vitality and reduced non-progressive motility of spermatozoon (p < .05). Testicular torsion significantly decreased all histopathological parameters compared to the sham group (p < .05). SMV pretreatment remarkably increased MSTD, GECT and Cosentino's score in comparison with the TD group (p < .05). A combination of Salvia miltiorrhiza with verapamil could reduce damages triggered by testicular torsion detorsion and improve sperm functionality parameters and oxidative stress defence systems.  相似文献   
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BackgroundIschemia-driven islet isolation procedure is one of the limiting causes of pancreatic islet transplantation. Ischemia-reperfusion process is associated with endothelium dysfunction and the release of pro-senescent microvesicles. We investigated whether pro-senescent endothelial microvesicles prompt islet senescence and dysfunction in vitro.Material and methodsPancreatic islets were isolated from male young rats. Replicative endothelial senescence was induced by serial passaging of primary porcine coronary artery endothelial cells, and microvesicles were isolated either from young passage 1 (P1) or senescent passage 3 (P3) endothelial cells. Islet viability was assessed by fluorescence microscopy, apoptosis by flow cytometry, and Western blot. Function was assessed by insulin secretion and islet senescence markers p53, p21, and p16 by Western blot. Microvesicles were stained by the PKH26 lipid fluorescent probe and their islet integration assessed by microscopy and flow cytometry.ResultsRegardless of the passage, half microvesicles were integrated in target islets after 24 hours incubation. Insulin secretion significantly decreased after treatment by senescent microvesicles (P3: 1.7 ± 0.2 vs untreated islet: 2.7 ± 0.2, P < .05) without altering the islet viability (89.47% ± 1.69 vs 93.15% ± 0.97) and with no significant apoptosis. Senescent microvesicles significantly doubled the expression of p53, p21, and p16 (P < .05), whereas young microvesicles had no significant effect.ConclusionPro-senescent endothelial microvesicles specifically accelerate the senescence of islets and alter their function. These data suggest that islet isolation contributes to endothelial driven islet senescence.  相似文献   
47.
Annals of Surgical Oncology - Racial/ethnic disparities in cancer outcomes may relate to variations in receipt of National Comprehensive Cancer Network (NCCN)&nbsp;guideline&nbsp;compliant...  相似文献   
48.
Sexuality and Disability - Sexual problems of hemodialysis patients are one of the most significant factors affecting their quality of life and families. On the other hand, an essential part of the...  相似文献   
49.
Porocarcinoma (synonym: malignant eccrine poroma) is a rare aggressive carcinoma type with terminal sweat gland duct differentiation. The squamous variant of porocarcinoma is even less frequent and might be indistinguishable from conventional squamous cell carcinoma (SCC). We herein describe the first case of a carcinoma presenting as a primary parotid gland malignancy in a 24-year-old male without any other primary tumor. Total parotidectomy and neck dissection were performed followed by adjuvant chemoradiation. The patient remained alive and well 10 months after diagnosis. Histology showed keratinizing SCC infiltrating extensively the parotid gland with subtle poroid cell features. Oncogenic HPV infection was excluded by DNA-based testing. NGS analysis using the TruSight RNA fusion panel (Illumina) revealed a novel YAP1-MAML2 gene fusion. This gene fusion was reported recently in a subset of cutaneous porocarcinoma and poroma. This case of poroid SCC (or squamoid porocarcinoma) adds to the differential diagnosis of SCC presenting as parotid gland tumor and highlights the value of molecular testing in cases with unusual presentation.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01181-9) contains supplementary material, which is available to authorized users.  相似文献   
50.
Portilla-Fernández  Eliana  Hwang  Shih-Jen  Wilson  Rory  Maddock  Jane  Hill  W. David  Teumer  Alexander  Mishra  Pashupati P.  Brody  Jennifer A.  Joehanes  Roby  Ligthart  Symen  Ghanbari  Mohsen  Kavousi  Maryam  Roks  Anton J. M.  Danser  A. H. Jan  Levy  Daniel  Peters  Annette  Ghasemi  Sahar  Schminke  Ulf  Dörr  Marcus  Grabe  Hans J.  Lehtimäki  Terho  Kähönen  Mika  Hurme  Mikko A.  Bartz  Traci M.  Sotoodehnia  Nona  Bis  Joshua C.  Thiery  Joachim  Koenig  Wolfgang  Ong  Ken K.  Bell  Jordana T.  Meisinger  Christine  Wardlaw  Joanna M.  Starr  John M.  Seissler  Jochen  Then  Cornelia  Rathmann  Wolfgang  Ikram  M. Arfan  Psaty  Bruce M.  Raitakari  Olli T.  Völzke  Henry  Deary  Ian J.  Wong  Andrew  Waldenberger  Melanie  O’Donnell  Christopher J.  Dehghan  Abbas 《European journal of epidemiology》2021,36(11):1143-1155

Common carotid intima-media thickness (cIMT) is an index of subclinical atherosclerosis that is associated with ischemic stroke and coronary artery disease (CAD). We undertook a cross-sectional epigenome-wide association study (EWAS) of measures of cIMT in 6400 individuals. Mendelian randomization analysis was applied to investigate the potential causal role of DNA methylation in the link between atherosclerotic cardiovascular risk factors and cIMT or clinical cardiovascular disease. The CpG site cg05575921 was associated with cIMT (beta?=??0.0264, p value?=?3.5?×?10–8) in the discovery panel and was replicated in replication panel (beta?=??0.07, p value?=?0.005). This CpG is located at chr5:81649347 in the intron 3 of the aryl hydrocarbon receptor repressor gene (AHRR). Our results indicate that DNA methylation at cg05575921 might be in the pathway between smoking, cIMT and stroke. Moreover, in a region-based analysis, 34 differentially methylated regions (DMRs) were identified of which a DMR upstream of ALOX12 showed the strongest association with cIMT (p value?=?1.4?×?10–13). In conclusion, our study suggests that DNA methylation may play a role in the link between cardiovascular risk factors, cIMT and clinical cardiovascular disease.

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