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971.
Huilin Su Li Li Benlin Cheng Junhao Zhu Qiangqiang Zhang Jinhua Xu Min Zhu 《Mycopathologia》2017,182(5-6):549-554
Infections caused by Trichophyton rubrum are very common in dermatological disease. It most often appears as superficial cutaneous mycosis, such as tinea manuum, tinea pedis, and tinea corporis. However, deep infection caused by T. rubrum was rarely reported. We describe a case of mixed type of deep infection caused by T. rubrum in a 45-year-old man with no significant immunodeficiency. This patient had a history of onychomycosis on the toenails without regular treatment for nearly 6 years. And, he had erythema, papule, and nodules on the submandibular area, neck, and chest for almost 1 year. After treated with intravenous infusion of cefotiam for 2 weeks, the lesion aggravated. The fungal direct microscopic examination of pyogenic fluid was positive, and the fungal cultures that produced reddish-brown and yellow pigment showed cottony, wooly, and white colony. After the DNA sequencing, it was identified as T. rubrum. We gave the patient oral terbinafine 250 mg per day and bifonazole cream for external use. Six months later, the patient’s skin lesion was disappeared, and healthy nail growth was seen in two-thirds of nail bed. The terbinafine is effective against deep infection caused by T. rubrum. 相似文献
972.
Tobias Lahmer Clarissa Prazeres da Costa Jürgen Held Sebastian Rasch Ursula Ehmer Roland M. Schmid Wolfgang Huber 《Mycopathologia》2017,182(7-8):701-708
Introduction
Pneumocystis jirovecii pneumonia (PCP) is a major cause of disease in immunocompromised individuals. Diagnosis is typically obtained by microscopy and/or PCR. For ambiguous PCR results, we evaluated the new biomarker 1,3-Beta-d-Glucan (BDG).Methods
BDG serum levels were assessed and correlated to PCR results in immunosuppressed patients with ARDS.Results
11 (22%) out of 50 patients had suspected PCP. APACHE II (26 vs. 24; p < 0.002), SOFA score (16 vs. 14; p < 0.010) and mortality rate (34 vs. 69% p < 0.004; 34 vs. 80% p < 0.003) were significantly altered in patients with positive (pPCR) and slightly positive (spPCR) PCJ PCR as compared to patients with no-PCP (nPCP). BDG levels were significantly lower in patients with nPCP (86; 30–315 pg/ml) than in patients with pPCR (589; 356–1000 pg/ml; p < 0.001) and spPCP (398; 297–516 pg/ml; p < 0.004) referring to the cutoff in this study for PCP of 275 pg/ml. An overall sensitivity (S) of 92% (95% CI 86–96%) and specificity (SP) of 84% (95% CI 79–85%) for PCP were found for the BDG Fungitell assay. In detail, S of 98% (95% CI 94–100%) and SP of 86% (95% CI 82–92%) for pPCP and S of 98% (95% CI 96–100%) and SP of 88% (95% CI 86–96%) for spPCO were found.Conclusion
Serum BDG levels were strongly elevated in PCP, and the negative predictive value is high. BDG could be used as a preliminary test for patients with suspected PCP, especially in patients with slightly positive PCR results.973.
Ewa Langner Marta K. Lemieszek Jacek M. Kwiecień Grażyna Rajtar Wojciech Rzeski Waldemar A. Turski 《Neurochemical research》2017,42(3):838-845
Kynurenic acid (KYNA) is an end stage product of tryptophan metabolism with a variety of functions in the human body, both in the central nervous system (CNS) and in other organs. Although its activity in the human brain has been widely studied and effects on neural cells were emphasized, the effect of KYNA on oligodendroglial cells remains unknown. Present study aims at describing the activity of high concentration of KYNA in OLN-93 cells. The inhibition of OLN-93 oligodendrocytes viability by KYNA in a medium with reduced serum concentration has been demonstrated. Although decreased metabolic activity of KYNA treated OLN-93 cells was shown, the cells proliferation was not altered. KYNA treatment did not alter morphology as well as expression level of cell cycle and proliferation regulating proteins. Furthermore, glutamate receptor antagonists and agonists did not alter the inhibitory effect of KYNA on viability of OLN-93 oligodendrocytes. This study contributes to the elucidation of effects of KYNA on oligodendrocytes in vitro, yet further analyses are necessary to explain the mechanisms behind the damage and loss of myelin sheaths. 相似文献
974.
975.
Lakshmi Machineni Anil Rajapantul Vandana Nandamuri Parag D. Pawar 《Bulletin of mathematical biology》2017,79(3):594-618
The resistance of bacterial biofilms to antibiotic treatment has been attributed to the emergence of structurally heterogeneous microenvironments containing metabolically inactive cell populations. In this study, we use a three-dimensional individual-based cellular automata model to investigate the influence of nutrient availability and quorum sensing on microbial heterogeneity in growing biofilms. Mature biofilms exhibited at least three structurally distinct strata: a high-volume, homogeneous region sandwiched between two compact sections of high heterogeneity. Cell death occurred preferentially in layers in close proximity to the substratum, resulting in increased heterogeneity in this section of the biofilm; the thickness and heterogeneity of this lowermost layer increased with time, ultimately leading to sloughing. The model predicted the formation of metabolically dormant cellular microniches embedded within faster-growing cell clusters. Biofilms utilizing quorum sensing were more heterogeneous compared to their non-quorum sensing counterparts, and resisted sloughing, featuring a cell-devoid layer of EPS atop the substratum upon which the remainder of the biofilm developed. Overall, our study provides a computational framework to analyze metabolic diversity and heterogeneity of biofilm-associated microorganisms and may pave the way toward gaining further insights into the biophysical mechanisms of antibiotic resistance. 相似文献
976.
Ana-Maria Croicu Angela M. Jarrett N. G. Cogan M. Yousuff Hussaini 《Bulletin of mathematical biology》2017,79(11):2649-2671
HIV infection is one of the most difficult infections to control and manage. The most recent recommendations to control this infection vary according to the guidelines used (US, European, WHO) and are not patient-specific. Unfortunately, no two individuals respond to infection and treatment quite the same way. The purpose of this paper is to make use of the uncertainty and sensitivity analysis to investigate possible short-term treatment options that are patient-specific. We are able to identify the most significant parameters that are responsible for ART outcome and to formulate some insights into the ART success. 相似文献
977.
Huzefa A. Raja Noemi D. Paguigan Jacques Fournier Nicholas H. Oberlies 《Mycological Progress》2017,16(5):535-552
Two new species of freshwater ascomycetes belonging to the genus Lindgomyces (Pleosporales, Dothideomycetes) are described and illustrated from submerged wood in North Carolina, USA. Lindgomyces carolinensis is characterized by immersed to erumpent ascomata, fissitunicate broadly cylindrical to clavate asci, and fusiform ascospores with acute ends surrounded by a large, fusiform gelatinous sheath. Lindgomyces cigarospora morphologically differs from L. carolinensis in that its ascospores are fusiform to cylindrical with rounded ends, without a large fusiform gelatinous sheath. These two new species nest in the family Lindgomycetaceae based on analyses of combined SSU and LSU rDNA sequence data. Phylogenetic analyses using ITS sequence data support the establishment of the new taxa as separate species within Lindgomyces. In addition to the new species, we report new ITS sequence data for L. cinctosporus and L. griseosporus from France, and L. ingoldianus from North Carolina, USA. We report a video exhibiting fissitunicate ascus dehiscence in L. carolinensis showing ascospore discharge and unraveling of the gelatinous sheath in real time. Chemical analysis of the organic extracts of L. carolinensis and L. cigarospora resulted in two known cyclodepsipeptides, Sch 378161 and Sch 217048. The in situ spatial mapping of these secondary metabolites on fungal cultures indicates the presence of both compounds on the surface of mycelia, as well as being exuded into the surrounding agar. 相似文献
978.
979.
Human epithelial ovarian cancer is a complex disease, with low 5-yr survival rate largely due to the terminal stage at diagnosis in most patients. MicroRNAs play critical roles during epithelial ovarian cancer progression in vivo and have also been shown to regulate characteristic of ovarian cancer cell line in vitro. Alterative microRNA-224 (microRNA-224) expression affects human epithelial ovarian cancer cell survival, apoptosis, and metastasis. However, people know little about the effects of microRNA-224 on epithelial ovarian cancer cell proliferation. In the current study, we found that the microRNA-224 expression level of human syngeneic epithelial ovarian cancer cells HO8910 (low metastatic ability) was lower than that of HO8910PM (high metastatic ability). Furthermore, microRNA-224 was confirmed to target KLLN in HO8910 and HO8910PM. The known KLLN downstream target cyclin A was regulated by microRNA-224 in HO8910 and HO8910PM. In addition, overexpression of microRNA-224 enhanced the proliferation abilities of HO8910 and knockdown of microRNA-224 suppressed the proliferation abilities of HO8910PM by KLLN-cyclin A pathway. Our results provide new data about microRNAs and their targets involved in proliferation of epithelial ovarian cancer cells by modulating the downstream signaling. 相似文献
980.
Jiao Zhao He Ma Leitao Wu Liang Cao Qianqian Yang Haijun Dong Zongren Wang Jing Ma Zhen Li 《In vitro cellular & developmental biology. Animal》2017,53(8):744-751
Several studies have indicated that microgravity can influence cellular progression, proliferation, and apoptosis in tumor cell lines. In this study, we observed that simulated microgravity inhibited proliferation and induced apoptosis in U251 malignant glioma (U251MG) cells. Furthermore, expression of the apoptosis-associated proteins, p21 and insulin-like growth factor binding protein-2 (IGFBP-2), was upregulated and downregulated, respectively, following exposure to simulated microgravity. These findings indicate that simulated microgravity inhibits proliferation while inducing apoptosis of U251MG cells. The associated effects appear to be mediated by inhibition of IGFBP-2 expression and stimulation of p21 expression. This suggests that simulated microgravity might represent a promising method to discover new targets for glioma therapeutic strategy. 相似文献