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Taati M Moghadasi M Dezfoulian O Asadian P Kheradmand A Abbasi M Zendehdel M 《Journal of physiology and biochemistry》2012,68(1):91-97
Ghrelin, the endogenous ligand for growth hormone secretagogue receptor, has been reported to prevent ischemia/reperfusion
(I/R) injury in various tissues by its antioxidant activity. Therefore, this study was aimed to investigate the effect of
ghrelin on sperm quality and antioxidant enzyme activity in a rat testicular ischemia/reperfusion injury model. Forty-two
male Wistar rats were divided into groups control, I/R, and I/R plus ghrelin. The right testes were rotated 720° for 1 h and
were allowed to reperfuse for 4 h and 30 days thereafter. Ghrelin (40 nmol/kg IP) or vehicle (physiological saline) was administrated
15 min before reperfusion. After 4 h of reperfusion, a right orchiectomy was performed to measure the biochemical parameters.
In addition, the sperm was collected from the epididymis after 30 days of reperfusion, and sperm characteristics were examined.
The malondialdehyde levels of the testis tissues were significantly increased, but a statistically significant decrease was
found in the superoxide dismutase, glutathione peroxidase, and catalase activities in the I/R group as compared with the control,
indicating I/R injury. The sperm evaluation showed a significant reduction in all characteristics resulted from I/R compared
with the control. In the ghrelin-treated group, the malondialdehyde values were significantly lowered, and only enzyme activity
of glutathione peroxidase showed significant increases compared with the I/R group. Ghrelin significantly enhanced sperm motility,
movement, and concentration but did not prevent I/R-induced reduction in membrane integrity in the testes of rats compared
to the I/R group. Our results suggest that ghrelin treatment has a protective role on IR-induced testicular injury, and this
effect may be due to its antioxidant properties. 相似文献
43.
Nomanpour B Ghodousi A Babaei T Jafari S Feizabadi MM 《Acta microbiologica et immunologica Hungarica》2012,59(2):171-184
We designed a multiplex real time PCR for rapid, sensitive and specific detection of Streptococcus pneumoniae, Legionella pneumophila, Chlamydophila pneumoniae and Mycoplasma pneumoniae. The study cases consisted of 129 patients with community acquired pneumonia (CAP). Bacteriological techniques were implemented for detection of the cultivable organisms. DNA were extracted from sputa, throat swabs, bronchoalveolar lavages and tracheal aspirates and used as templates in real time PCR. The primers and probes were designed for cbpA (S. pneumoniae), p1adhesin (M. pneumoniae), mip (L. pneumophila) and ompA (C. pneumoniae). After optimization of real time PCR for every organism, the experiments were continued in multiplex in a single tube. Of 129 CAP specimens, the positive cultures included 14 (10.85%) for S. pneumoniae, 9 (6.98%) for L. pneumophila and 3 (2.33%) for M. pneumoniae. Four specimens (3.10%) were positive for C. pneumoniae by real time PCR. The sensitivity of our real time PCR was 100% for all selected bacteria. The specificity of the test was 98.26%, 98.34%, 100% and 100% for S. pneumoniae, L. pneumophila, M. pneumoniae and C. pneumoniae, respectively. This is the first report on the use of multiplex real time PCR for detection of CAP patients in the Middle East. The method covers more than 90% of the bacterial pathogens causing CAP. 相似文献
44.
J Kornej C Reinhardt J Kosiuk A Arya G Hindricks V Adams D Husser A Bollmann 《PloS one》2012,7(8):e44165
Aims
This study investigated the possible association between hs-CRP as well as hs-CRP changes and rhythm outcome after AF catheter ablation.Methods
We studied 68 consecutive patients with AF undergoing catheter ablation. hs-CRP levels were measured using commercially available assays before and 6 months after catheter ablation. Serial 7-day Holter ECGs were used to detect AF recurrences.Results
Early AF recurrence (ERAF, within one week) was observed in 38%, while late AF recurrence (LRAF, between 3 and 6 months) occurred in 18% of the patients. None of the baseline clinical or echocardiographic variables was predictive of ERAF or LRAF. Baseline hs-CRP measured 2.07±1.1 µg/ml and was not associated with ERAF and LRAF. At 6 months, hs-CRP levels were comparable with baseline values (2.14±1.19 µg/ml, p = 0.409) and were also not related with LRAF. However, patients with LRAF showed an hs-CRP increase from 2.03±0.61 to 2.62±1.52 µg/ml (p = 0.028). Patients with an hs-CRP change in the upper tertile (>0.2 µg/ml) had LRAF in 32% as opposed to 11% (p = 0.042) in patients in the lower (<−0.3 µg/ml) or intermediate (−0.3–0.2 µg/ml) tertile.Conclusions
Changes in hs-CRP but not baseline hs-CRP are associated with rhythm outcome after AF catheter ablation. This finding points to a link between an inflammatory response and AF recurrence in this setting. 相似文献45.
Ashrafian H Czibik G Bellahcene M Aksentijević D Smith AC Mitchell SJ Dodd MS Kirwan J Byrne JJ Ludwig C Isackson H Yavari A Støttrup NB Contractor H Cahill TJ Sahgal N Ball DR Birkler RI Hargreaves I Tennant DA Land J Lygate CA Johannsen M Kharbanda RK Neubauer S Redwood C de Cabo R Ahmet I Talan M Günther UL Robinson AJ Viant MR Pollard PJ Tyler DJ Watkins H 《Cell metabolism》2012,15(3):361-371
46.
Bowen DG Shoukry NH Grakoui A Fuller MJ Cawthon AG Dong C Hasselschwert DL Brasky KM Freeman GJ Seth NP Wucherpfennig KW Houghton M Walker CM 《Journal of virology》2008,82(10):5109-5114
The inhibitory receptor programmed death-1 (PD-1) is present on CD8(+) T cells in chronic hepatitis C virus (HCV), but expression patterns in spontaneously resolving infections are incompletely characterized. Here we report that PD-1 was usually absent on memory CD8(+) T cells from chimpanzees with resolved infections, but sustained low-level expression was sometimes observed in the absence of apparent virus replication. PD-1-positive memory T cells expanded and displayed antiviral activity upon reinfection with HCV, indicating conserved function. This animal model should facilitate studies of whether PD-1 differentially influences effector and memory T-cell function in resolved versus persistent human infections. 相似文献
47.
Radziewicz H Ibegbu CC Hon H Osborn MK Obideen K Wehbi M Freeman GJ Lennox JL Workowski KA Hanson HL Grakoui A 《Journal of virology》2008,82(20):9808-9822
A majority of patients infected with hepatitis C virus (HCV) do not sustain an effective T-cell response, and viremia persists. The mechanism leading to failure of the HCV-specific CD8+ T-cell response in patients developing chronic infection is unclear. We investigated apoptosis susceptibility of HCV-specific CD8+ T cells during the acute and chronic stages of infection. Although HCV-specific CD8+ T cells in the blood during the acute phase of infection and in the liver during the chronic phase were highly activated and expressed an effector phenotype, the majority was undergoing apoptosis. In contrast, peripheral blood HCV-specific CD8+ T cells during the chronic phase expressed a resting memory phenotype. Apoptosis susceptibility of HCV-specific CD8+ T cells was associated with very high levels of programmed death-1 (PD-1) and low CD127 expression and with significant functional T-cell deficits. Further evaluation of the “death phase” of HCV-specific CD8+ T cells during acute HCV infection showed that the majority of cells were dying by a process of cytokine withdrawal, mediated by activated caspase 9. Contraction during the acute phase occurred rapidly via this process despite the persistence of the virus. Remarkably, in the chronic phase of HCV infection, at the site of infection in the liver, a substantial frequency of caspase 9-mediated T-cell death was also present. This study highlights the importance of cytokine deprivation-mediated apoptosis with consequent down-modulation of the immune response to HCV during acute and chronic infections. 相似文献
48.
The high affinity IgE receptor, Fc epsilonRI, plays a key role in the immunological pathways involved in allergic asthma. Previously we have demonstrated that human neutrophils isolated from allergic asthmatics express a functional Fc epsilonRI, and therefore it was of importance to examine the factors regulating its expression. In this study, we found that neutrophils from allergic asthmatics showed increased expression of Fc epsilonRI-alpha chain surface protein, total protein and mRNA compared with those from allergic non asthmatics and healthy donors (p<0.001). Interestingly, in neutrophils isolated from allergic asthmatics, Fc epsilonRI-alpha chain surface protein and mRNA expression were significantly greater during the pollen season than outside the pollen season (n = 9, P = 0.001), an effect which was not observed either in the allergic non asthmatic group or the healthy donors (p>0.05). Allergen exposure did not affect other surface markers of neutrophils such as CD16/Fc gammaRIII or IL-17R. In contrast to stimulation with IgE, neutrophils incubated with TH2 cytokines IL-9, GM-CSF, and IL-4, showed enhanced Fc epsilonRI-alpha chain surface expression. In conclusion, these results suggest that enhanced Fc epsilonRI expression in human neutrophils from allergic asthmatics during the pollen season can make them more susceptible to the biological effects of IgE, providing a possible new mechanism by which neutrophils contribute to allergic asthma. 相似文献
49.
Arash Rafii Pejman Mirshahi Mary Poupot Anne-Marie Faussat Anne Simon Elodie Ducros Eliane Mery Bettina Couderc Raphael Lis Jerome Capdet Julie Bergalet Denis Querleu Francoise Dagonnet Jean-Jacques Fournié Jean-Pierre Marie Eric Pujade-Lauraine Gilles Favre Jeanine Soria Massoud Mirshahi 《PloS one》2008,3(12)
Background
The microenvironment plays a major role in the onset and progression of metastasis. Epithelial ovarian cancer (EOC) tends to metastasize to the peritoneal cavity where interactions within the microenvironment might lead to chemoresistance. Mesothelial cells are important actors of the peritoneal homeostasis; we determined their role in the acquisition of chemoresistance of ovarian tumours.Methodology/Principal Findings
We isolated an original type of stromal cells, referred to as “Hospicells” from ascitis of patients with ovarian carcinosis using limiting dilution. We studied their ability to confer chemoresistance through heterocellular interactions. These stromal cells displayed a new phenotype with positive immunostaining for CD9, CD10, CD29, CD146, CD166 and Multi drug resistance protein. They preferentially interacted with epithelial ovarian cancer cells. This interaction induced chemoresistance to platin and taxans with the implication of multi-drug resistance proteins. This contact enabled EOC cells to capture patches of the Hospicells membrane through oncologic trogocytosis, therefore acquiring their functional P-gp proteins and thus developing chemoresistance. Presence of Hospicells on ovarian cancer tissue micro-array from patients with neo-adjuvant chemotherapy was also significantly associated to chemoresistance.Conclusions/Significance
This is the first report of trogocytosis occurring between a cancer cell and an original type of stromal cell. This interaction induced autonomous acquisition of chemoresistance. The presence of stromal cells within patient''s tumour might be predictive of chemoresistance. The specific interaction between cancer cells and stromal cells might be targeted during chemotherapy. 相似文献50.
Ali Golchin Simzar Hosseinzadeh Masumeh Staji Masoud Soleimani Abdolreza Ardeshirylajimi Arash Khojasteh 《Journal of cellular biochemistry》2019,120(9):15410-15421
Electrospun composite scaffolds show high ability to be used in regenerative medicine and drug delivery, due to the nanofibrous structure and high surface area to volume ratio. In this study, we used nanofibrous scaffolds fabricated by chitosan (CS), poly(vinyl alcohol) (PVA), carbopol, and polycaprolactone using a dual electrospinning technique while curcumin (Cur) incorporated inside of the CS/PVA fibers. Scaffolds were fully characterized via scanning electron microscopy, water contact angle, tensile measurement, hydration, protein adsorption, and wrinkled tests. Furthermore, viability of the buccal fat pad-derived mesenchymal stem cells (BFP-MSCs) was also investigated using MTT assay for up to 14 days while cultured on these scaffolds. Cell cycle assay was also performed to more detailed evaluation of the stem cells growth when grown on scaffolds (with and without Cur) compared with the culture plate. Results demonstrated that Cur loaded nanofibrous scaffold had more suitable capability for water absorption and mechanical properties compared with the scaffold without Cur and it could also support the stem cells viability and proliferation. Cur release profile showed a decreasing effect on BFP-MSCs viability in the initial stage, but it showed a positive effect on stem cell viability in a long-term manner. In general, the results indicated that this nanofibrous scaffold has great potential as a delivery of the Cur and BFP-MSCs simultaneously, and so holds the promising potential for use in various regenerative medicine applications. 相似文献