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61.
There is accumulating evidence that excitotoxicity and oxidative stress resulting from excessive activation of glutamate (N-methyl-d-aspartate) NMDA receptors are major participants in striatal degeneration associated with 3-nitropropionic acid (3NP) administration.
Although excitotoxic and oxidative mechanisms are implicated in 3NP toxicity, there are conflicting reports as to whether
NMDA receptor antagonists attenuate or exacerbate the 3NP-induced neurodegeneration. In the present study, we investigated
the involvement of NMDA receptors in striatal degeneration, protein oxidation and motor impairment following systemic 3NP
administration. We examined whether NMDA receptor antagonists, memantine and ifenprodil, influence the neurotoxicity of 3NP.
The development of striatal lesion and protein oxidation following 3NP administration is delayed by memantine but not affected
by ifenprodil. However, in behavioral experiments, memantine failed to improve and ifenprodil exacerbated the motor deficits
associated with 3NP toxicity. Together, these findings suggest caution in the application of NMDA receptor antagonists as
a neuroprotective agent in neurodegenerative disorders associated with metabolic impairment. 相似文献
62.
Two new species of the genus Corollospora, namely, C. anglusa sp. nov. with its anamorph Varicosporina anglusa sp. nov. and C. portsaidica sp. nov., which were isolated from the coast of the Mediterranean Sea in Egypt, are described in this article based on morphological
and molecular evidence. The two new species have one-septate ascospores. Corollospora anglusa resembles C. gracilis by having narrow one-septate hyaline ascospores; however, they differ in ascomata and ascospore dimensions and in pure culture
characteristics. Single-ascospore culture of C. anglusa produces the conidia of its anamorph, whereas an anamorph has not been reported for C. gracilis. Varicosporina anglusa differs from the other two known Varicosporina species by having conidial branches that are filamentous, rectangularly branched, hypha like, and disarticulated into two-
or one-celled fragments. Corollospora portsaidica is morphologically similar to C. cinnamomea, but the two species differ in the dimensions, shape, and ornamentation of the ascospores. The new Corollospora species were confirmed to be divergent from other similar Corollospora species based on phylogenetic analyses of partial sequences of the LSU rDNA region. 相似文献
63.
64.
Durgeau A El Hage F Vergnon I Validire P de Montpréville V Besse B Soria JC van Hall T Mami-Chouaib F 《Journal of immunology (Baltimore, Md. : 1950)》2011,187(11):5532-5539
Decreased antigenicity of cancer cells is a major problem in tumor immunology. This is often acquired by an expression defect in the TAP. However, it has been reported that certain murine Ags appear on the target cell surface upon impairment of TAP expression. In this study, we identified a human CTL epitope belonging to this Ag category. This epitope is derived from preprocalcitonin (ppCT) signal peptide and is generated within the endoplasmic reticulum by signal peptidase and signal peptide peptidase. Lung cancer cells bearing this antigenic peptide displayed low levels of TAP, but restoration of their expression by IFN-γ treatment or TAP1 and TAP2 gene transfer abrogated ppCT Ag presentation. In contrast, TAP upregulation in the same tumor cells increased their recognition by proteasome/TAP-dependent peptide-specific CTLs. Thus, to our knowledge, ppCT(16-25) is the first human tumor epitope whose surface expression requires loss or downregulation of TAP. Lung tumors frequently display low levels of TAP molecules and might thus be ignored by the immune system. Our results suggest that emerging signal peptidase-generated peptides represent alternative T cell targets, which permit CTLs to destroy TAP-impaired tumors and thus overcome tumor escape from CD8(+) T cell immunity. 相似文献
65.
Faten Zahran Mohamed Yousry Mostafa Hussein Ibrahim Mohey El-Deen Marwa Sayed Sabea 《Molecular biology reports》2014,41(3):1461-1468
Hepatocellular carcinoma (HCC) is a worldwide neoplasm for which early diagnosis is difficult and the prognosis is usually poor. Overexpression of cyclooxygenase 2 (COX-2) has been suggested to be associated with hepatocarcinogenesis. Although several COX-2 inhibitors have been used in hepatoma therapy, the genetic background between COX-2 and HCC remains largely unknown. In this study, the association of genotypic polymorphisms in COX-2 with HCC was investigated. 25 healthy individuals served as control (group I), group II: 50 HCV infection patients without any complications, group III: 50 HCV infected patients complicated with cirrhosis and group IV: 75 HCV infected patients complicated with (45 localized and 30 metastatic) HCC from Zagazig University Hospital in Egypt were genotyped by a PCR–RFLP method. The results showed that, no differences in distribution between the HCC and other groups were found. We found ?1195A allele carriers had a higher risk of HCC with HCV infection. As regard the obtained results of serum AFU, a significant increase was detected in HCC as compared with cirrhosis, hepatitis and healthy control groups (p < 0.001). Concerning the obtained results of serum AFP, when HCC group was compared with cirrhosis, hepatitis and healthy controls, a significant increase was observed (p < 0.001). In conclusion: identification of SNP in COX-2 gene promoter and evaluation of serum AFU and AFP give a red light in early detection of HCC which may be reduce its fatal incidence. 相似文献
66.
Maryam Nasr Esfahani Saad Sulieman Joachim Schulze Kazuko Yamaguchi‐Shinozaki Kazuo Shinozaki Lam‐Son Tran 《Plant biotechnology journal》2014,12(3):387-397
Chickpea (Cicer arietinum) is an important pulse crop in many countries in the world. The symbioses between chickpea and Mesorhizobia, which fix N2 inside the root nodules, are of particular importance for chickpea's productivity. With the aim of enhancing symbiotic efficiency in chickpea, we compared the symbiotic efficiency of C‐15, Ch‐191 and CP‐36 strains of Mesorhizobium ciceri in association with the local elite chickpea cultivar ‘Bivanij’ as well as studied the mechanism underlying the improvement of N2 fixation efficiency. Our data revealed that C‐15 strain manifested the most efficient N2 fixation in comparison with Ch‐191 or CP‐36. This finding was supported by higher plant productivity and expression levels of the nifHDK genes in C‐15 nodules. Nodule specific activity was significantly higher in C‐15 combination, partially as a result of higher electron allocation to N2 versus H+. Interestingly, a striking difference in nodule carbon and nitrogen composition was observed. Sucrose cleavage enzymes displayed comparatively lower activity in nodules established by either Ch‐191 or CP‐36. Organic acid formation, particularly that of malate, was remarkably higher in nodules induced by C‐15 strain. As a result, the best symbiotic efficiency observed with C‐15‐induced nodules was reflected in a higher concentration of the total and several major amino metabolites, namely asparagine, glutamine, glutamate and aspartate. Collectively, our findings demonstrated that the improved efficiency in chickpea symbiotic system, established with C‐15, was associated with the enhanced capacity of organic acid formation and the activities of the key enzymes connected to the nodule carbon and nitrogen metabolism. 相似文献
67.
Rym Chamakh-Ayari Rachel Bras-Gon?alves Narges Bahi-Jaber Elodie Petitdidier Wafa Markikou-Ouni Karim Aoun Javier Moreno Eugenia Carrillo Poonam Salotra Himanshu Kaushal Narender Singh Negi Jorge Arevalo Francesca Falconi-Agapito Angela Privat Maria Cruz Julie Pagniez Gérard-Marie Papierok Faten Bel Haj Rhouma Pilar Torres Jean-Loup Lemesre Mehdi Chenik Amel Meddeb-Garnaoui 《PloS one》2014,9(5)
PSA (Promastigote Surface Antigen) belongs to a family of membrane-bound and secreted proteins present in several Leishmania (L.) species. PSA is recognized by human Th1 cells and provides a high degree of protection in vaccinated mice. We evaluated humoral and cellular immune responses induced by a L. amazonensis PSA protein (LaPSA-38S) produced in a L. tarentolae expression system. This was done in individuals cured of cutaneous leishmaniasis due to L. major (CCLm) or L. braziliensis (CCLb) or visceral leishmaniasis due to L. donovani (CVLd) and in healthy individuals. Healthy individuals were subdivided into immune (HHR-Lm and HHR-Li: Healthy High Responders living in an endemic area for L. major or L. infantum infection) or non immune/naive individuals (HLR: Healthy Low Responders), depending on whether they produce high or low levels of IFN-γ in response to Leishmania soluble antigen. Low levels of total IgG antibodies to LaPSA-38S were detected in sera from the studied groups. Interestingly, LaPSA-38S induced specific and significant levels of IFN-γ, granzyme B and IL-10 in CCLm, HHR-Lm and HHR-Li groups, with HHR-Li group producing TNF-α in more. No significant cytokine response was observed in individuals immune to L. braziliensis or L. donovani infection. Phenotypic analysis showed a significant increase in CD4+ T cells producing IFN-γ after LaPSA-38S stimulation, in CCLm. A high positive correlation was observed between the percentage of IFN-γ-producing CD4+ T cells and the released IFN-γ. We showed that the LaPSA-38S protein was able to induce a mixed Th1 and Th2/Treg cytokine response in individuals with immunity to L. major or L. infantum infection indicating that it may be exploited as a vaccine candidate. We also showed, to our knowledge for the first time, the capacity of Leishmania PSA protein to induce granzyme B production in humans with immunity to L. major and L. infantum infection. 相似文献
68.
69.
Patrice?Njomnang?Soh Boris?Delaunay Elie?Bou?Nasr Martine?Delannes Michel?Soulie Eric?HuygheEmail author 《Andrologie》2014,24(1):13
Purpose
To assess sexual functions and behaviors of men treated by penile brachytherapy for a cancer of the penis.Materials and methods
Thirty eight men (19 patients treated by penile brachytherapy for a cancer of the penis and 19 age paired-matched controls) participated in a survey about sexuality. The mean age of patients and controls were 73.2 +/- 11.7 and 70.0 +/- 10.5 years, respectively (NS). Controls were men without penile pathology, without history of cancer and no evidence of cognitive impairment. All agreed to participate in the survey about sexuality using 2 questionnaires : the IIEF questionnaire, which explores 4 domains of sexual functions, namely erection, satisfaction, orgasm and desire, and a questionnaire created using the BASIC IDEA grid, which addresses nine domains: behavior, affect, sensation, self-image, cognition, interpersonal, drugs, expectation and attitude.Results
Patients had better scores than controls in 3 domains of the IIEF: erection, desire and satisfaction. These results contrasted with the frequency of intercourse and the quality of erection (evaluated through the BASIC IDEA questionnaire) that were not significantly different between the two populations. Patients also had significantly higher frequency of masturbation (p <0.001) lower worry about sexual performance and higher expected satisfaction for future life (p: 0.021) than controls.Conclusion
Penile brachytherapy is a treatment of cancer of the penis that seems to have a moderated impact on sexual functions since most of sexual scores are not inferior in these patients than in age pair-matched controls.70.
Yusei Miyazaki Rui Li Ayman Rezk Hétoum Misirliyan Craig Moore Nasr Farooqi Mayra Solis Lorna Galleguillos Goiry Omar de Faria Junior Van Duc Dang David Colman Ajit Singh Dhaunchak Jack Antel Jennifer Gommerman Alexandre Prat Simon Fillatreau Amit Bar-Or 《PloS one》2014,9(8)
Clinical trial results demonstrating that B-cell depletion substantially reduces new relapses in patients with multiple sclerosis (MS) have established that B cells play a role in the pathophysiology of MS relapses. The same treatment appears not to impact antibodies directed against the central nervous system, which underscores the contribution of antibody-independent functions of B cells to disease activity. One mechanism by which B cells are now thought to contribute to MS activity is by over-activating T cells, including through aberrant expression of B cell pro-inflammatory cytokines. However, the mechanisms underlying the observed B cell cytokine dysregulation in MS remain unknown. We hypothesized that aberrant expression of particular microRNAs might be involved in the dysregulated pro-inflammatory cytokine responses of B cells of patients with MS. Through screening candidate microRNAs in activated B cells of MS patients and matched healthy subjects, we discovered that abnormally increased secretion of lymphotoxin and tumor necrosis factor α by MS B cells is associated with abnormally increased expression of miR-132. Over-expression of miR-132 in normal B cells significantly enhanced their production of lymphotoxin and tumor necrosis factor α. The over-expression of miR-132 also suppressed the miR-132 target, sirtuin-1. We confirmed that pharmacological inhibition of sirtuin-1 in normal B cells induces exaggerated lymphotoxin and tumor necrosis factor α production, while the abnormal production of these cytokines by MS B cells can be normalized by resveratrol, a sirtuin-1 activator. These results define a novel miR-132-sirtuin-1 axis that controls pro-inflammatory cytokine secretion by human B cells, and demonstrate that a dysregulation of this axis underlies abnormal pro-inflammatory B cell cytokine responses in patients with MS. 相似文献