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991.
Chromoblastomycosis is one of the most frequent chronic infections caused by melanized fungi. In order to evaluate the clinical characteristics of chromoblastomycosis in Mainland China, we performed an evidence-based review of published literature. PubMed and Chinese-language database of CNKI, VIP and Wanfang data during January 1990–August 2011 were searched. Epidemiology, clinical features, laboratory findings, therapy and prognosis were analyzed. Cladophialophora carrionii was the most common causative agent in the north of the Mainland China, and Fonsecaea monophora and F. pedrosoi were the most common agents in the southern part of the Mainland China. Infection commonly initiated after the etiologic agents gain entrance through puncture wounds and more common involved extremities of the males. Skin lesions were found in different sites, like the extremities, buttocks, trunk and face, and presented diversity morphology. There were about seven different clinical types found in Mainland China: plaque type, tumoral type, cicatricial type, verrucous type, pseudo-vacuole type, eczymatous type and mixed type of lesions. The success of treatment for chromoblastomycosis was related to the causative agent, the clinical form and severity of the lesions. Most of the patients could be treated successfully with the physical treatment, chemotherapy and/or combination therapy. The itraconazole, terbinafine or a combination of both were commonly medication for these mycosis patients. Physical methods were usually indicated to support chemotherapy with some severe forms and long-lasting cases. Photodynamic therapy has been extended from the oncological field to that of antimicrobial chemotherapy in these years. We applied it on some recalcitrant cases of chromoblastomycosis and found its good clinical response, and hopeful it could be a promising therapy in near future.  相似文献   
992.

Background

Glutathione S-transferase (GST) variants have been considered as risk factors for the pathogenesis of primary open angle glaucoma (POAG). However, the results have been inconsistent. In this study, we performed a meta-analysis to assess the association between GSTM1 and GSTT1 null genotypes and the risk for POAG.

Methods

Published literature from PubMed and EMBASE databases was retrieved. All studies evaluating the association between GSTM1/GSTT1 variants and POAG were included. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed- or random-effects model.

Results

14 studies (1711 POAG cases and 1537 controls) were included in the meta-analysis of GSTM1 genotypes and 10 studies (1306 POAG cases and 1114 controls) were included in the meta-analysis of GSTT1 genotypes. The overall result showed that the association between GSTM1 and GSTT1 null genotypes and risk for POAG was not statistically significant (GSTM1: OR = 1.19, 95% CI = 0.82–1.73, p = 0.361; GSTT1: OR = 1.26, 95% CI = 0.77–2.06, p = 0.365). The results by ethnicity showed that the association between the GSTM1 null genotype and risk for POAG is statistically significant in East Asians (OR = 1.41, 95% CI = 1.04–1.90, p = 0.026), but not in Caucasians (OR = 1.13, 95% CI = 0.69–1.84, p = 0.638) and Latin-American (OR = 1.09, 95% CI = 0.62–1.92, p = 0.767). In addition, there was no significant association of GSTT1 null genotype with risk for POAG in either ethnic population.

Conclusions

The present meta-analysis suggested that there might be a significant association of GSTM1 null genotype with POAG risk in East Asians.  相似文献   
993.
Nm23 is a family of genes encoding the nucleoside diphosphate (NDP) kinase, which functions in a wide variety of biological processes, including growth, development, differentiation and tumor metastasis. In this study, a novel nm23 gene, designated as Mrnm23, was identified from the freshwater giant prawn Macrobrachium rosenbergii. The full-length cDNA was 776 bp in length, encoding for a protein of 176 amino acids with one typical NDP kinase domain that harbored all the crucial residues for nucleotide binding and enzymatic activity. Like human novel nm23-H1B, the putative protein contained a unique 21-amino-acid NH2-terminal extension as compared to human nm23 (nm23-H1) homologs. Further, 3 extra amino acid residues prolonged the COOH-terminus. The Mrnm23 was ubiquitously expressed in all tissues examined, including androgenic gland, gill, heart, liver, muscle, ovary, and testis. In situ hybridization to gonad sections indicated that the Mrnm23 mRNA was localized in the cytoplasm of cup-base of differentiating spermatids, in the spike of the umbrella-shaped spermatozoa and in the cytoplasm of the early previtellogenic oocytes, suggesting that the Mrnm23 has potential roles in spermiogenesis and early differentiation of oocyte.  相似文献   
994.
To investigate the molecular mechanism of silkworm resistance to BmNPV infection, we constructed a near-isogenic line (BC8) with BmNPV resistance using highly resistant (NB) and highly susceptible parental strains (306). We investigated variations in the gene expression in the midguts of BmNPV-infected BC8 and 306 at 12 h pi using the microarray. 92 differentially expressed genes were identified. Real-time qPCR analysis confirmed that 10 genes were significantly up-regulated or down-regulated in the midguts of BC8 and NB compared to 306. To our knowledge, we first defined the role of the amino acid transporter and 26S proteasome in insect antiviral. However, serine protease was not completely consistent with data of reported previously in insect antiviral. The role of the 5 genes (Bm123, Bm122, COP β′, aquaporin, glycoside hydrolases) was also demonstrated in insect antiviral. Our results provided new insights into the molecular mechanism of the Bombyx mori immune response against BmNPV infection.  相似文献   
995.
Abstract

Glycyrrhiza glabra L. is considered an important source of bioactive compounds. This study aimed at the development of an efficient solution for the treatment of oral candidiasis. Several extracts of Glycyrrhiza glabra L. were prepared using different solvents and their potential in vitro antifungal activity was assessed. Ethanolic extracts showed the most promising results against C. albicans. This extract was incorporated into mucoadhesive nanoparticles (PLA, PLGA and alginate), which were further included in an oral gel, an oral film and a toothpaste, respectively. The results showed that nanoparticles were successfully produced, presenting a mean size among 100–900?nm with high encapsulation efficiency. In vitro studies showed that the most bioadhesive formulation was the oral film with extract-loaded PLGA nanoparticles, followed by the toothpaste with extract-loaded alginate nanoparticles and the oral gel with extract-loaded PLA nanoparticles.  相似文献   
996.
The meso-scale structure of symmetric diblock copolymer under cylindrical confinement is studied by dissipative particle dynamics (DPD). The simulation results show that coiled cylindrical geometry is favored in the presence of larger cylinder radius (R/L 0>~1.5), and the number of rings depends on the cylinder radius. Because of the cylinder wall's selectivity, each block can form the central core, but only the preferential block forms the outmost layer. An approximately linear relationship exists between structure transition point, which is approximately in proportion to the 3/5 exponential of chain length of copolymer and number of layers. As the cylinder radius is decreased, a helical morphology is found. Lamellae parallel to the underside of the cylinder appear when the cylinder radius is made smaller (R/L 0 < ~1.1).  相似文献   
997.
The mechanism and dynamical properties for the title reaction have been investigated theoretically. Three reaction pathways have been found. Geometries, vibrational frequencies, infra-red (IR) intensities and relative energies for various stationary points in the three reaction channels have been determined respectively. The corresponding rate constants at the B3LYP/6-31++G(2d,2p) level have been deduced over a wide temperature range of 200–2000 K by using canonical variational transition state theory with small curvature tunnelling effect. Solvent effects are taken into account via the Onsager model of self-constant reaction field at the same level of theory. This preliminary study shows that the complex formation is favoured by the use of water solvent.  相似文献   
998.
Honeydew production plays a key role in mutualism between the mealybugs and ants. However, no studies have focused on the amount and circadian rules of honeydew excreted by Phenacoccus solenopsis Tinsley, a new invasive species which has conditional mutualism with Solenopsis invicta Buren in China. To address this problem, we measured the weight and estimated honeydew production in all stages of development of the invasive mealybug, P. solenopsis, as well as its honeydew production on tomato (Solanum lycopersicun), Hibiscus rosa-sinensis, and cotton (Gossypium sp.) for 24 h. The honeydew excreted by each instar of the mealybug in H. rosa-sinensis was measured for 2 weeks. Our results revealed that the weight of mealybugs significantly varied at different development stages. Host plants had no significant effect on the weight of nymphs, although the weight of a single adult reared on S. lycopersicun was significantly heavier than those reared on H. rosa-sinensis and G. sp. The amount of honeydew excreted by the 1st instar nymphs in S. lycopersicum was significantly greater than that on H. rosa-sinensis and G. sp. Each instar mealybug produced more honeydew when fed with S. lycopersicum compared with H. rosa-sinensis and G. sp. The amount of honeydew excreted by mealybugs when provisioned with H. rosa-sinensis was no different from mealybugs provisioned with G. spp. while in the same instar. The amount of honeydew excreted by the 1st and 2nd instar nymphs was not significantly different on the same host plant. However, there was a significant difference between the 3rd instar nymph and the adult. The amount of honeydew excreted by a single adult when provisioned with H. rosa-sinensis decreased from 3085.3 μg to 572.0 μg in 2 weeks. The 2nd instar nymph, 3rd instar nymph, and adult excreted honeydew more frequently during the day than at night, while the frequency of honeydew excretion of the 1st instar nymph had no significant difference between daytime and night.  相似文献   
999.
Since adult neurogenesis became a widely accepted phenomenon, much effort has been put in trying to understand the mechanisms involved in its regulation. In addition, the pathophysiology of several neuropsychiatric disorders, such as depression, has been associated with imbalances in adult hippocampal neurogenesis. These imbalances may ultimately reflect alterations at the cell cycle level, as a common mechanism through which intrinsic and extrinsic stimuli interact with the neurogenic niche properties. Thus, the comprehension of these regulatory mechanisms has become of major importance to disclose novel therapeutic targets. In this review, we first present a comprehensive view on the cell cycle components and mechanisms that were identified in the context of the homeostatic adult hippocampal neurogenic niche. Then, we focus on recent work regarding the cell cycle changes and signaling pathways that are responsible for the neurogenesis imbalances observed in neuropathological conditions, with a particular emphasis on depression.  相似文献   
1000.
Accumulating evidence suggests that inflammatory processes in the central nervous system that are mediated by microglial activation play important roles in several neurodegenerative disorders. Therefore, development of methods for microglial inhibition is considered an important strategy in the search for neuroprotective agents. Caffeic acid phenethyl ester (CAPE) is distributed wildly in nature, but rapid decomposition by esterase leads to its low bioavailability. In this study, we investigated the effects of KS370G, a novel caffeic acid phenylethyl amide, on microglial activation. KS370G significantly inhibited the release of nitric oxide (NO) and the expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Treatment with KS370G also induced heme oxygenase (HO)-1 and suppressors of cytokine signaling (SOCS)-3 expression in the microglia. Furthermore, the anti-inflammatory effects of KS370G were found to be regulated by phosphorylated adenosine monophosphate-activated protein kinase-α (AMPK-α) translocated to the nucleus. Moreover, KS370G showed significant anti-neuroinflammatory effects on microglial activation in vivo and on motor behavior as well. The protective effect of KS370G was weakened by an AMPK inhibitor Compound C. This study focuses on the importance of key molecular determinants of inflammatory homeostasis, AMPK, HO-1, and SOCS-3, and their possible involvement in anti-neuroinflammatory responses.  相似文献   
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