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991.
992.
PurposeEplerenone (EPL) is a selective mineralocorticoid receptor antagonist used for treatment of chronic central serous chorioretinopathy which characterized by accumulation of subretinal fluid causing a localized area of retinal detachment. unfortunately, EPL suffers from poor oral bioavailability due to poor aqueous solubility in addition to high hepatic first pass metabolism.MethodAiming to improve its oral bioavailability, EPL-loaded nanostructured lipid carriers (NLCs) were prepared by the emulsification solvent evaporation method and in-vitro evaluated for particle size (PS), polydispersity index (PDI), zeta potential (ZP), and entrapment efficiency (EE%). A D-optimal design was used for study the effect of liquid lipid to solid lipid ratio, surfactant type and percentage on PS, PDI, EE%, and for data optimization. The optimized EPL-loaded NLCs system was further evaluated using in-vitro drug release and ex-vivo permeation studies through rabbit intestine in comparison to EPL aqueous suspension. The physicochemical properties of the drug in the optimized system were further examined using FT-IR and X-ray diffraction studies.ResultsThe resultant NLCs showed small PS (100.85–346.60 nm), homogenous distribution (0.173–0.624), negatively charged particles (ZP −20.20 to −36.75 mV), in addition to EE% (34.31–70.64%). The optimized EPL-loaded NLCs system with a desirability value of 0.905 was suggested through the Design expert® software, containing liquid to solid lipid ratio (2:1) in presence of 0.43%w/v Pluronic® F127 as a surfactant. The optimized EPL-loaded NLCs system showed a PS of 134 nm and PDI of 0.31, in addition to high EE% (76 ± 6.56%w/w), and ZP (-32.37 mV). The ex-vivo permeation study showed two-fold higher drug permeation through rabbit intestine compared to that from the aqueous drug suspension after 24 h, confirming the ability of optimized EPL-loaded NLCs system as successful oral targeting delivery carrier.ConclusionOur results pave the way for a new oral nanotherapeutic approach toward CSCR treatment. In-vivo study is currently under investigation.  相似文献   
993.

Liver biopsy (LB) is the cornerstone in the management of patients with liver diseases. However, a lot of queries had emerged about its role following the end of the interferon era. The aim of this study was to re-evaluate the current role of LB in the diagnosis of liver diseases. All patients who had underwent LB at the Department of Hepatology, National Liver Institute, from January 2015 through December 2018 were recruited. Indications for LB, pathology reports and medical records of all cases were retrieved, reviewed and statistically analyzed. A total of 275 liver biopsies were collected, 191 males and 84 females with mean age 41.22 ± 13.36 years. Etiological diagnosis made by histopathological evaluation was 48 drug-induced liver injury (DILI), 42 nonalcoholic fatty liver disease (NAFLD), 34 chronic hepatitis B, or C with cholestasis, 29 autoimmune hepatitis, 34 primary sclerosing cholangitis, 13 primary biliary cholangitis, 7 autoimmune overlap syndrome, 13 active bilharziasis and 10 Wilson’s disease. Minor number of cases was diagnosed by different other etiologies. Initial diagnosis was made by liver biopsy and confirmed by clinical response and laboratory findings. Liver biopsy is still considered as the gold standard diagnostic measure of different liver diseases representing an integral component of management decisions in hepatology.

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994.
In Egypt, hepatocellular carcinoma (HCC) ranks as the second largest cause of cancer mortality. PRDM1 is a tumor suppressor gene essential for the differentiation and regulation activity of plasma cells and T cells. It plays a vital role in T cell exhaustion of chronic viral infection and HCC. We aimed to study the role of PRDM1 gene polymorphism in HCV and HCC-related to hepatitis C virus (HCV) progress in Egyptians. The case-control study included 300 Egyptian patients divided into 100 HCC,100 cirrhosis, and 100 control. Laboratory investigations were done for some clinicopathological biomarkers, including liver function tests, complete blood picture, serum alpha-fetoprotein, and hepatitis markers (HBsAg, anti-HCV-Ab). TaqMan allelic discrimination assay technique was used to genotype PRDM1 gene polymorphism. Multivariant analysis (logistic regression) assessed the association between the polymorphisms with HCC progression and designed the suggested model for HCC prediction. The frequencies of the G allele and GG phenotype in the control group were significantly more than that of the HCC and cirrhosis group. However, GA genotypes and A allele frequencies significantly increased in the HCC patients than in cirrhosis and controls. In addition, by comparing the HCC group and the non-HCC group (controls and cirrhotic patients), the subjects carrying AA or GA have 2 times more risk to develop HCC than those carrying GG genotypes (odd ratio = 2.045% and 95% confidence interval are (1.123−3.722) p = 0.019). Multivariate analysis results suggested a model of Aspartate transaminase (AST), Albumin, and PRDM1 polymorphism to predict the risk of HCC in Egyptians. In addition, PRDM1 polymorphism has an association with HCC prognosis (tumor size). For PRDM1 polymorphism, the A allele and AA might be considered as HCC-related to the HCV risk factor. In addition, AST, Albumin, and PRDM1 polymorphism predict the risk of HCC in Egyptians Therefore, the polymorphism might help in identifying the susceptible Egyptians to HCC. In addition, polymorphism might have a role in HCC prognosis.  相似文献   
995.
Ezrin is a member of the ezrin-radixin-moesin family of proteins, which link the actin-containing cytoskeleton to the plasma membrane. Overexpression of ezrin protein is correlated with the metastatic potential in several cancers. Little is known about the distribution of ezrin in normal epidermis and nonmelanoma skin cancer; therefore, in the current study, we examined the immunohistochemical expression of ezrin in normal skin (10 biopsies) and epithelial skin tumors (25 basal cell carcinoma [BCC] and 20 squamous cell carcinoma [SCC]). Ezrin was expressed in epidermis of all normal controls with a prominent membranous pattern compared with 93.3% positivity in malignant cases with a significant higher intensity (assessed by H score) in favor of the latter (P = .002). Cytoplasmic expression of ezrin either alone or associated with membranous expression was both seen in BCC and SCC. The median value of H score in SCC (160) cases was higher than that in BCC (60). H score values of ezrin expression in BCC was significantly higher in tumors arising in sites other than the head and neck (P = .04). In SCC, the intensity of ezrin expression tended to be associated with advanced stage (P = .08). Our study demonstrated the probable tumorigenic role of ezrin in epithelial skin tumor formation. It may enhance local invasion or metastasis of epithelial skin tumors, which necessitates further larger study to clarify. The intensity rather than the pattern of ezrin expression had a more probable impact on the tumor behavior.  相似文献   
996.
Handedness and language cerebral lateralization   总被引:2,自引:0,他引:2  
Repetitive transcranial magnetic stimulation (rTMS) induces lateralized speech arrest consistent with cerebral dominance for language. Studies of language cerebral dominance in differently handed healthy subjects have been limited. Using a focal magnetic coil, we examined the degree of consistency between handedness as evaluated by the Stanley Coren Score and hemispheric dominance for language as determined by rTMS in 25 right- and 25 left-handed medical students. They were categorized according to the score into 24 strongly right-handed, 1 moderately right-handed, 19 strongly left-handed, 3 moderately left-handed and 3 ambidextrous (equally-handed). In the strongly right-handed subjects, left-sided language cerebral dominance was recorded in 87.5% of the subjects, and bilateral cerebral representation in 8.2%, and right-sided language cerebral dominance in 4.2%. In the strongly left-handed subjects, 73.7% had left-side language cerebral dominance, 15.8% had bilateral cerebral representation and 10.5% had right-side cerebral language dominance. In mixed handed subjects (moderately right, left and ambidextrous), bilateral cerebral representation was observed in 57% and left-side cerebral language dominance in 43%. There were 27 subjects who developed speech arrest at 140% of motor threshold, the others developed speech arrest at lower intensities. Speech lateralized to the left-side cerebral dominance in strongly right- and left-handed subjects, but bilateral cerebral representation was frequent in mixed handedness and right-sided cerebral dominance rarely occurred. Electronic Publication  相似文献   
997.
We investigated the effect of a single injection of rotenone into the striatum on the development of oxidative stress, nigrostriatal cell injury and motor alterations in rats. Rotenone (1, 3, 5 and 9 mM; 5 μL/rat) or the vehicle (dimethyl sulfoxide) was injected into the right striatum. Control rats received the vehicle only. Rats were allowed to recover from the operation and were tested for behavioural changes on 7th and 30th days after rotenone injection. Biochemical markers of oxidative stress including malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide, paraoxonase 1 (PON1) activity and Q10 enzyme as well as monoamine neurotransmitters in the brain were determined after 30 days of rotenone treatment. Histopathology and tyrosine hydroxylase immunohistochemistry were also performed. Results: Intrastriatal injection of rotenone at 9 mM caused immediate death of rats. No mortality was observed with the lower concentrations of the pesticide. Rotenone at 1–5 mM resulted in increased brain oxidative stress in a dose-dependent manner. MDA increased by 23.5–64.9 %, while GSH decreased by 20.4–24.1 % in the contralateral cerebral hemisphere. Nitric oxide increased by 20.2–41.7 % in ipsilateral cortex. PON1 activity decreased by 12.5–38.2 % in ipsilateral cerebral cortex and by 31.2–65.3 % in ipsilateral striatum, respectively, but coenzyme Q10 increased in the ipsilateral cortex by 21–26.3 %. There was decreased dopamine and serotonin in the ipsilateral striatum after rotenone injection. Tyrosine hydroxylase immunoreactivity was markedly decreased in ipsilateral substantia nigra in the rotenone-treated in contrast to the vehicle-treated rats. Rotenone increased the number of degenerated cells in substantia nigra in a dose-dependent manner. It also caused depletion of pigment granules from cells. Degenerative changes were also observed in the contralateral hippocampus and cortex especially after the highest dose of rotenone. The number of spontaneous rears made during 30 min in the cylinder was decreased in both limbs; the decrease being more evident in the ipsilateral side. Thus, a single intrastriatal injection of rotenone (a) caused a significant nigrostriatal degeneration and loss of dopamine and serotonin from the striatum; (b) elicited cell degeneration in the hippocampus and cortex; (c) induced oxidative stress and neuronal injury (this latter effect of rotenone was not region specific); and (d) the motor deficits (decreased rearing activity) occurred in both limbs.  相似文献   
998.
Hepatitis C virus (HCV)-specific cell-mediated immunity (CMI) has been reported among exposed individuals without viremia or seroconversion. Limited data are available regarding CMI among at-risk, seronegative, aviremic Egyptian health care workers (HCW), where HCV genotype 4 predominates. We investigated CMI responses among HCW at the National Liver Institute, where over 85% of the patients are HCV infected. We quantified HCV-specific CMI in 52 seronegative aviremic Egyptian HCW using a gamma interferon (IFN-γ) enzyme-linked immunospot assay in response to 7 HCV genotype 4a overlapping 15-mer peptide pools covering most of the viral genome. A positive HCV-specific IFN-γ response was detected in 29 of 52 HCW (55.8%), where 21 (40.4%) had a positive response for two to seven HCV pools and 8 (15.4%) responded to only one pool. The average numbers of IFN-γ total spot-forming cells (SFC) per million peripheral blood mononuclear cells (PBMC) (± standard error of the mean [SEM]) in the 29 responding and 23 nonresponding HCW were 842 ± 141 and 64 ± 15, respectively (P < 0.001). Flow cytometry indicated that both CD4+ and CD4 T cells produced IFN-γ. In summary, more than half of Egyptian HCW demonstrated strong HCV multispecific CMI without viremia or seroconversion, suggesting possible clearance of low HCV exposure(s). These data suggest that detecting anti-HCV and viremia to determine past exposure to HCV can lead to an underestimation of the true disease exposure and that CMI response may contribute to the low degree of chronic HCV infection in these HCW. These findings could have strong implications for planning vaccine studies among populations with a high HCV exposure rate. Further studies are needed to determine whether these responses are protective.  相似文献   
999.
Hepatitis C virus (HCV) infection represents a major health problem in many areas of the world, especially Egypt. Hepatic progenitor cells (HPCs) and hepatic stellate cells (HSCs) have been implicated in fibrosis progression in chronic HCV. The aim of this study was to investigate the role of HPCs and HSCs in chronic HCV infection and the relationship between both cell types. This retrospective study was conducted on 100 chronic HCV patients. Immunohistochemistry was performed on liver tissue sections for cytokeratin 19 (progenitor cell markers), smooth muscle actin (stellate cell markers), matrix metalloproteinase‐9 (MMP‐9), and transforming growth factor beta (TGF‐ß). The necroinflammatory activity was significantly related to the number of isolated HPCs and TGF‐ß expression (p = 0.003 and p = 0.001 respectively). Advanced stages of fibrosis showed significantly increase number of HPCs (p = 0.001), higher ratio of HSCs (p = 0.004), more expression of TGF‐ß (p = 0.001) and MMP‐9 (p = 0.001). There was a significant direct correlation between immunoexpression of HPCs and HSCs for isolated cells (r = 0.569, p = 0.001) and ductular reaction (r = 0.519, p = 0.001). Hepatic progenitor cells and stellate cells play a significant role in the development and progression of fibrosis in chronic HCV. More interestingly, the significant direct correlation between HPCs and HSCs suggests a synergistic interrelation.  相似文献   
1000.
Parasitology Research - Searching for new effective and safe treatment of Giardia lamblia (G. lamblia) parasite is mandatory. The aim was to evaluate the in vitro and in vivo effectiveness of an...  相似文献   
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