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61.
Dirofilariasis is a common parasitic disease in both domestic and wild animals around the world, with canines as the principal reservoir host and mosquitoes as the vector. Human ophthalmic dirofilariasis is an uncommon condition, but there have been reports from many parts of the world, including Africa, Australia, the Americas, Europe, and Asia. Ophthalmic involvement with Dirofilaria may present itself as periorbital, subconjunctival, orbital, or intraocular infections. In this report, we present a case of orbital dirofilariasis with lateral rectus muscle involvement. To our knowledge, this is the first orbital dirofilariasis case reported in Iran. Although debulking of the tumor usually leads to resolution, our patient showed an episode of recurrence after biopsy. Complete recovery was achieved after a spontaneous discharge, without the need for systemic medication. 相似文献
62.
Aziza Kouchou Naoual Rais Jeanne-Chantal Thoisy Joëlle Duplay Malika Ghazi Françoise Elsass 《Soil & Sediment Contamination》2017,26(3):259-276
To investigate the relevance of biochemical parameters in biogeochemical mechanisms of the soil, it is important to gather data related to different soil types under different pedogeoclimatic conditions. In this study, we investigated on the calcareous agricultural soils in the Saiss plain (North Morocco). Four agricultural soils exposed to multi-metal (Cr, Cu, Zn, and Ni) and organic matter (OM) contamination as a result of irrigation with Oued Fez and Oued Sebou waters that are affected by urban and industrial activities around the city of Fez were studied and compared to a reference site irrigated with uncontaminated water. The study concerned soil physicochemical properties and the activity of a range of enzymes [phosphatase (PHOS), arylsulfatase (SULF), urease (UREA), arylamidase (AMID), β-galactosidase (GALA), glucosidase (GLUC), and laccase (LACA)] related to nutrients cycles. Pearson's correlations between these parameters showed that soil enzymatic activities (PHOS, SULF, UREA, GALA, GLUC, and LACA) were correlated positively with heavy metals (Cu, Zn, and Cr) concentrations in the soil and also with dissolved organic carbon (DOC), and negatively with the aromaticity (AROM) of these compounds. Interestingly, analysis of intra-site correlations showed strong relationships among enzyme activities in the reference soil, while in contaminated soils, these activities were largely unrelated to each other. It was concluded that soil irrigation with heavy-metal- and OM-contaminated watercourses over decades has resulted in soils with high enzymatic activities function and nutrient turnover but altered relationships among geochemical cycles. 相似文献
63.
Rath P Demange P Saurel O Tropis M Daffé M Dötsch V Ghazi A Bernhard F Milon A 《The Journal of biological chemistry》2011,286(37):32525-32532
PorA and PorH are two small membrane proteins from the outer membrane of Corynebacterium glutamicum, which have been shown to form heteromeric ion channels and to be post-translationally modified by mycolic acids. Any structural details of the channel could not be analyzed so far due to tremendous difficulties in the production of sufficient amounts of protein samples. Cell-free (CF) expression is a new and remarkably successful strategy for the production of membrane proteins for which toxicity, membrane targeting, and degradation are key issues. In addition, reaction conditions can easily be modified to modulate the quality of synthesized protein samples. We developed an efficient CF expression strategy to produce the channel subunits devoid of post-translational modifications. (15)N-labeled PorA and PorH samples were furthermore characterized by NMR and gave well resolved spectra, opening the way for structural studies. The comparison of ion channel activities of CF-expressed proteins with channels isolated from C. glutamicum gave clear insights on the influence of the mycolic acid modification of the two subunits on their functional properties. 相似文献
64.
Majid Ghorbani Javid Ali Sorooshzadeh Seyed Ali Mohammad Modarres Sanavy Iraj Allahdadi Foad Moradi 《Plant Growth Regulation》2011,65(2):305-313
Phytohormones, such as auxin and cytokinin, are known to be involved in the regulation of plant responses to salinity stress
and counteract the adverse effect of stress conditions. This work investigated the effects of the exogenous spraying of indole-3-acetic
acid (IAA) and kinetin (KIN) during the reproductive phase on grain yield by examining the 1000-grain weight and filled-grain
percentage as well as the changes in starch, total soluble sugars, sucrose, glucose and fructose concentrations in the grains
of two rice cultivars under salt stress. The results indicated that the applied IAA and KIN led to an increased grain yield,
1000-grain weight and filled-grain percentage for both rice cultivars under salt stress. The storage starch content in the
grain of the salt-sensitive cultivar was more than that in the salt-tolerant cultivar under IAA application compared with
KIN, whereas a decrease in the total soluble sugar content was observed with both IAA and KIN treatments, in comparison to
the non-hormone treatment. Interestingly, this study showed that IAA led to a much higher increase in the sucrose content
in grain, as compared to the KIN. Furthermore, this experiment suggests that glucose and fructose may play important roles
during salt stress because there were clearly higher concentrations of these sugars in the grain of the stressed cultivars
under IAA and KIN application: it appears that their accumulation was the earliest response detected during the grain-filling
period in rice. Finally, this work indicated that an increase in the rice grain yield, 1000-grain weight and filled-grain
percentage are associated with an increase in the contents of starch, sucrose, glucose and fructose in grain caused by the
application of IAA and KIN. 相似文献
65.
A total of 250 broilers in a completely randomized design selected to evaluate the effect of different levels of chromium (Cr) supplementation on performance, carcass traits and some blood parameters of heat-stressed broiler chicks. All birds were kept under heat stress temperature (33?±?3°C) and divided into five treatments groups. Each treatment consisted of five pens with 10 birds in each pen. The basal diets were supplemented with 0?ppb (control), 800?ppb Cr-L-Met (T(1)), 1,200?ppb Cr-L-Met (T(2)) or 800?ppb CrCl(3) (T(3)), and 1,200?ppb CrCl(3) (T(4)). The feed intake and body mass were measured at 10, 21, and 42?days of age. Blood samples were collected from two birds in each replicates to determine biological and hematological values at 28 and 42?days of age. There were no significant difference in mass gain and feed conversion of broilers that received Cr supplementations compared with controls. The serum glucose concentration decreased in broilers received organic chromium methionine supplements compared with other treatments groups. Slight but not significant increases were observed in serum high-density lipoprotein (HDL) concentration of treated groups than controls while the mean serum HDL concentration was significantly higher in T(2) group compared with control group. Serum low-density lipoprotein level decreased in broiler received organic Cr supplements (p?0.05). 相似文献
66.
Alipour M Gholami MR Jafari Anarkooli I Sohrabi D Tajki J Pourheidar M 《Cellular and molecular neurobiology》2011,31(5):765-773
The present work was designed to investigate the potential protective effects of post-ischemic treatment with aminoguanidine
(AG) on sciatic nerve ischemia/reperfusion (I/R) injury in rat. Seventy-two rats were divided into 12 groups (n = 6). We used ischemia model in these groups by occluding the right common iliac and femoral arteries for 3 h with a silk
suture 6-0 using slipknot technique. Treatment groups (2, 4, 6, 8, 10, and 12) received 150 mg/kg AG intraperitoneally 24 h
after induction of ischemia. After certain time intervals of reperfusion (2, 4, 7, 14, and 28 days), the function of the hind
limb was assessed using behavioral scores based on gait, racing reflex, toe spread, pinch sensitivity, paw position, and grasp.
After euthanasia, sciatic nerves were removed at the end of reperfusion times and sections were cut at 5 μm, then were stained
for light microscopy studies and graded for ischemic fiber degeneration (IFD), edema, and apoptosis. Maximal behavioral deficit
occurred at 7 days of reperfusion. The comparison of behavioral score pertaining to the control and AG groups revealed significant
differences and showed also a better time course in recovery (P < 0.05). Other than 3 and 4 groups, the amount of edema in AG treatment groups showed significant differences compared with
control groups (P < 0.05). IFD was also significantly decreased in the AG treatment groups than controls. Most importantly, I/R-induced apoptosis
were improved significantly on the 4th, 7th, and 14th days of reperfusion in AG-treated groups compared to controls. In conclusion, our findings suggest that post-ischemic
administration of AG exhibits protective effect against sciatic nerve I/R injury. 相似文献
67.
Maryam Arab Firouzjaei Mohammad Reza Jafari Mehdi Eskandari Iraj Jafari Anarkoli Mohsen Alipour 《Cellular and molecular neurobiology》2014,34(3):343-350
Cognitive dysfunction occurs in patients with diabetes mellitus. The objective of this study was to examine whether bilateral intrahippocampal CA1 (intra-CA1) injection of aminoguanidine (AG) can either affect the Bcl-2 family gene expression or reduce the diabetic imposing abnormalities of passive avoidance learning (PAL) and memory. Rats were divided into five groups: control (C), control treated with normal saline (CS), control treated with AG (S-AG), diabetics (D), and diabetics treated with AG (D-AG). Diabetes mellitus was induced by a single intraperitoneal injection of streptozotocin (STZ) (50 mg/kg). AG (30 μg/rat) or vehicle was administered intra-CA1 bilaterally at the onset of hyperglycemia. PAL was assessed 7 weeks later. Animals were killed, and hippocampus was dissected following the behavioral test. The expressions of Bax, Bcl-2, and Bcl-xl mRNAs were measured using semiquantitative RT-PCR technique. The result of passive avoidance task showed that AG significantly improved the cognitive performance in diabetic rats. Moreover, AG treatment decreased the levels of Bcl-2 and Bcl-xL expressions in diabetic group. The ratio of Bax/Bcl-2 and Bax/Bcl-xL decreased significantly in AG-treated diabetic animals. In conclusion, initial treatment with AG by intra-CA1 micro-injection improves the impaired passive avoidance task in STZ-induced diabetic rats which may be related to the decreased Bax/Bcl-2 and Bax/Bcl-xL ratios. 相似文献
68.
Negar Seyed Tahereh Taheri Charline Vauchy Magalie Dosset Yann Godet Ali Eslamifar Iraj Sharifi Olivier Adotevi Christophe Borg Pierre Simon Rohrlich Sima Rafati 《PloS one》2014,9(10)
Background
There are several reports demonstrating the role of CD8 T cells against Leishmania species. Therefore peptide vaccine might represent an effective approach to control the infection. We developed a rational polytope-DNA construct encoding immunogenic HLA-A2 restricted peptides and validated the processing and presentation of encoded epitopes in a preclinical mouse model humanized for the MHC-class-I and II.Methods and Findings
HLA-A*0201 restricted epitopes from LPG-3, LmSTI-1, CPB and CPC along with H-2Kd restricted peptides, were lined-up together as a polytope string in a DNA construct. Polytope string was rationally designed by harnessing advantages of ubiquitin, spacers and HLA-DR restricted Th1 epitope. Endotoxin free pcDNA plasmid expressing the polytope was inoculated into humanized HLA-DRB1*0101/HLA-A*0201 transgenic mice intramuscularly 4 days after Cardiotoxin priming followed by 2 boosters at one week interval. Mice were sacrificed 10 days after the last booster, and splenocytes were subjected to ex-vivo and in-vitro evaluation of specific IFN-γ production and in-vitro cytotoxicity against individual peptides by ELISpot and standard chromium-51(51Cr) release assay respectively. 4 H-2Kd and 5 HLA-A*0201 restricted peptides were able to induce specific CD8 T cell responses in BALB/C and HLA-A2/DR1 mice respectively. IFN-γ and cytolytic activity together discriminated LPG-3-P1 as dominant, LmSTI-1-P3 and LmSTI-1-P6 as subdominant with both cytolytic activity and IFN-γ production, LmSTI-1-P4 and LPG-3-P5 as subdominant with only IFN-γ production potential.Conclusions
Here we described a new DNA-polytope construct for Leishmania vaccination encompassing immunogenic HLA-A2 restricted peptides. Immunogenicity evaluation in HLA-transgenic model confirmed CD8 T cell induction with expected affinities and avidities showing almost efficient processing and presentation of the peptides in relevant preclinical model. Further evaluation will determine the efficacy of this polytope construct protecting against infectious challenge of Leishmania. Fortunately HLA transgenic mice are promising preclinical models helping to speed up immunogenicity analysis in a human related mouse model. 相似文献69.
70.