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111.
Circadian and stress systems have a crucial role in adaptation of organisms to environmental challenges. This study investigates the ability of Oscillatoria brevis (O. brevis) β-carotene extract (βC) in modulating the circadian alternations of locomotor activity (LA) and serum melatonin (M) rhythms under chronic unpredictable stress (CUS) in rats. Twenty rats (5 rats/group) were used in monitoring LA using running wheels. Eighty rats (20 rats/group) were used in observing circadian serum M profile. Rats were randomly divided into four groups, viz. control, βC-treated, CUS-exposed, and “βC-treated&CUS-exposed” groups. CUS-exposure was applied for 21 days. One hour before exposure, βC was daily administered (10 mg/kg), intraperitoneally (IP). Blood was sampled at 6-h intervals for 5 rats/time point at Zeitgeber (ZT) 3, 9, 15, and 21. Results demonstrated that unstressed rats exhibited circadian M pattern and nocturnal LA rhythm with acrophase around ZT 21 and ZT 15, respectively. CUS-exposure revealed a disturbance in these patterns. Phase shifting of M and LA profiles was recorded. A decrease M acrophase and a significant decrease in LA (p < 0.05) were recorded at ZT 9. Daily βC administration in stressed rats modulates the CRs alternation induced by CUS. It may be concluded that βC ameliorated the induced alternations in circadian rhythms.  相似文献   
112.
Alternaria alternata is the most common fungal pathogen of tomatoes in Upper Egypt. Morphological identification of this fungus is challenging; therefore, this study searched for new classification tools based on molecular techniques. Using a dilution plating method, 67 strains of A. alternata were isolated from 34 samples of rotten tomato fruits representing the Giza 80 and Edkawy cultivars. The collected strains were identified using the amplification products of the internal transcribed spacer (ITS) region, glyceraldehyde 3‐phosphate dehydrogenase (Gpd) and Alt a1, which is a gene involved in the production of most of the allergens produced by A. alternata. The screening revealed that A. alternata constituted more than half of the total fungi recovered from rotten tomatoes in this study. According to the phylogenetic analysis using these three loci, the collected strains clustered in accordance with the host cultivar type from which they had been isolated. Specific gene random primer polymerase chain reaction (SGRP‐PCR) techniques indicated that the A. alternata population in the tested region has a high genetic diversity. The pathogenicity test showed that most of the A. alternata isolates (67.2%) were highly pathogenic, and no correlation was found between the phylogenetic analysis and pathogenicity. In addition, the influence of the fungicide Disan 80% on the collected strains showed significant differences that were attributed to the source of isolation.  相似文献   
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The liver is an important organ, and hepatic ischemia–reperfusion (IR) injury is a frequent pathophysiological process that can cause significant morbidity and mortality. Thus, our study aimed to investigate the effect of targeting PI3K/p-Akt/eNOS (phosphoinositide 3-kinase/phospho-protein kinase B/endothelial nitric oxide synthase), Nrf2/HO-1 (nuclear factor-erythroid 2-related factor-2/heme oxygenase-1), and NF-κB/p53 (nuclear factor-κB/tumor protein 53) signaling pathways by using angiotensin (1–7) [ang-(1–7)] against hepatic injury induced by IR. Thirty-two male rats were included in sham group, ang-(1–7)-treated group, hepatic IR group, and hepatic IR group treated with ang-(1–7). The levels of hepatic ang-(1–7), angiotensin II (Ang II), angiotensin-converting enzyme 2 (ACE2), HO-1, malondialdehyde (MDA), PI3K, and p-Akt were assessed. The expressions of eNOS and B-cell leukemia/lymphoma-2 (BCL-2) in the liver were determined. Histological assessment and immunohistochemical expression of NF-κB, p53, and Nrf2 were carried out. The levels of reduced glutathione (GSH), aspartate aminotransferase (AST), alanine aminotransferase (ALT), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in serum were estimated. Results showed that administration of ang-(1–7) to hepatic IR rats led to significant amelioration of hepatic damage through a histological evaluation that was associated with significant upregulation of the expressions of PI3K/p-Akt/eNOS and Nrf2/HO-1 with downregulation of NF-κB/p53 signaling pathways. In conclusion, PI3K/p-Akt/eNOS and Nrf2/HO-1 signaling pathways are involved in the protective effects of ang-(1–7) against hepatic damage induced by IR. Therefore, ang-(1–7) can be used to prevent hepatic IR, which occurs in certain conditions such as liver transplantation, hemorrhagic shock, and severe infection.  相似文献   
116.
Context: Topical treatment of skin disease needs to be strategic to ensure high drug concentration in the skin with minimum systemic absorption.

Objective: The aim of this study was to produce semisolid nanostructured lipid carrier (NLC) formulations, for topical delivery of the corticosteroid drug, diflucortolone valerate (DFV), with minimum systemic absorption.

Method: NLC formulations were developed using a high shear homogenization combined with sonication, using Precirol® ATO5 or Tristearin® as the solid lipid, Capryol? or isopropyl myristate as the liquid lipid and Poloxamer® 407 as surfactant. The present study addresses the influence of different formulations composition as solid lipid, liquid lipid types and concentrations on the physicochemical properties and drug release profile from NLCs.

Results and discussion: DFV-loaded NLC formulations possessed average particle size ranging from 160.40?nm to 743.7?nm with narrow polydispersity index. The encapsulation efficiency was improved by adding the lipid-based surfactants (Labrasol® and Labrafil® M1944CS) to reach 68%. The drug release from the investigated NLC formulations showed a prolonged release up to 12?h. The dermatopharmacokinetic study revealed an improvement in drug deposition in the skin with the optimized DFV-loaded NLC formulation, in contrast to a commercial formulation.

Conclusion: NLC provides a promising nanocarrier system that work as reservoir for targeting topical delivery of DFV.  相似文献   

117.
Late blight disease of potato caused by Phytophthora infestans poses a significant threat to potato production in Ethiopia. The development of new high yielding genotypes with adequate late blight disease resistance will provide a strong component of an integrated management strategy for farmers. The objective of this study was to determine late blight resistance and yield of potato clones under field condition in north‐western Ethiopia. Twenty‐four clones (17 from the International Potato Centre B3C2 population and seven widely grown cultivars) were evaluated at three locations. The experiment was laid in a randomized complete block design with two replications. Late blight resistance and yield‐related traits were determined. Results showed that clones differ significantly for all traits across locations. The following five clones combine high to moderate resistance to late blight with high yields: 396029.250, 395017.229, 396004.263, 396034.103 and 395077.12. These clones are useful genetic resources for resistance breeding against late blight disease and for enhanced yields.  相似文献   
118.
This study aimed to assess the expression of S100A4, Twist and E-cadherin (mRNA and protein) in urothelial bladder cancer, investigate the correlation between them and evaluate their association with the clinicopathological features of the disease. The study included 54 patients diagnosed as urothelial bladder cancer of different stages and grades. The expression levels of S100A4, Twist and E-cadherin (mRNA and protein) in tissue samples were determined by quantitative RT-PCR and immunohistochemistry. The expression of S100A4 and Twist was significantly upregulated while E- cadherin was significantly downregulated in urothelial bladder cancer tissues compared to the adjacent surrounding normal bladder tissues at both mRNA and protein levels (p?<?0.001). Expression levels of S100A4 and Twist were significantly higher in recurrent tumor than in non-recurrent tumors (p?<?0.001) while the expression level of E-cadherin was significantly lower in recurrent tumors than in non-recurrent tumors at both mRNA and protein levels (p?<?0.001). There was a significant positive correlation between S100A4 and Twist expressions (r?=?0.875, p?<?0.001) while significant negative correlations were found between E- cadherin and S100A4 expressions(r=- 0.803, p?<?0.001) and between E-cadherin and Twist (r?=??0.809, p?<?0.001). Up-regulation of S100A4 and Twist and down-regulation of E-cadherin in urothelial bladder cancer tissues compared to adjacent normal tissues were observed. There was a significant negative correlation between S100A4 and E- cadherin and between E- cadherin and Twist expression. However, there was a significant positive correlation between S100A4 and Twist expressions. Furthermore, the alterations in the gene expression were associated with disease stage and grade.  相似文献   
119.
Phyllody disease is a threat to sesame production in Kerman province, southeastern Iran. RFLP analysis of PCR products of phytoplasma-specific 16S rRNA gene (1.8 kb) and phylogenetic analyses of 16S-23S rDNA spacer region (SR) sequence indicated that the predominant agent associated with sesame phyllody in Kerman province is a phytoplasma with 100% similarity with eggplant big bud, and peanut witches’-broom phytoplasmas, members of “Candidatus Phytoplasma aurantifolia” from Iran and China, respectively. Among the samples tested, only one strain (SPhSr1), had a unique RFLP profile and its SR was 100% similar in nucleotide sequence with the phytoplasma carried by Orosius albicinctus and Helianthus annus witches’-broom phytoplasma from Iran, members of “Ca. Phytoplasma trifolii”. Virtual RFLP patterns of SPhJ2 (representative of the predominant PCR-RFLP profiles) SR sequence were identical to those of peanut witches’-broom phytoplasma (16SrII-A, JX871467). However, SPhSr1 SR sequence patterns resemble (99.7%) those of vinca virescence phytoplasma (16SrVI-A, AY500817).  相似文献   
120.
Heat shock proteins (HSPs) are molecular chaperones involved in protein folding, assembly and transport, and which play critical roles in the regulation of cell growth, survival and differentiation. We set out to test the hypothesis that HSP27 protein is expressed in the human testes and its expression varies with the state of spermatogenesis. HSP27 expression was examined in 30 human testicular biopsy specimens (normal spermatogenesis, maturation arrest and Sertoli cell only syndrome, 10 cases each) using immunofluorescent methods. The biopsies were obtained from patients undergoing investigations for infertility. The seminiferous epithelium of the human testes showing normal spermatogenesis had a cell type-specific expression of HSP27. HSP27 expression was strong in the cytoplasm of the Sertoli cells, spermatogonia, and Leydig cells. Alternatively, the expression was moderate in the spermatocytes, weak in the spermatids and absent in the spermatozoa. In testes showing maturation arrest, HSP27 expression was strong in the Sertoli cells, weak in the spermatogonia, and spermatocytes. It was absent in the spermatids and Leydig cells. In Sertoli cell only syndrome, HSP27 expression was strong in the Sertoli cells and absent in the Leydig cells. We report for the first time the expression patterns of HSP27 in the human testes and show differential expression during normal spermatogenesis, indicating a possible role in this process. The altered expression of this protein in testes showing abnormal spermatogenesis may be related to the pathogenesis of male infertility.  相似文献   
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