共查询到20条相似文献,搜索用时 0 毫秒
1.
Klasinc Romana Riesenhuber Martin Bacher Andreas Willinger Birgit 《Mycopathologia》2019,184(1):107-113
Mycopathologia - This report describes a case of invasive Exophiala dermatitidis infection after double lung transplantation in a 76-year-old man. After thoracotomy, the patient’s wound... 相似文献
2.
3.
Human infection by Cunninghamella bertholletiae occurs almost exclusively in immunocompromised patients. Infections due to this microorganism have been most frequently diagnosed
in patients with hematological malignancies, with neutropenia and in diabetes mellitus patients. This work reports a case
of fungal infection by Cunninghamella bertholletiae isolated from blood in a man with a complex clinical picture, involving diabetes and pharmacological immunosupression. Blood
culture at room temperature and at 37 °C on Sabouraud agar grew a single mold with characteristic properties of Cunninghamella. In the microscopic morphology, were found wide, non-septate, branching hyphae with erect sporangiophores terminated in swollen vesicles and sporangioles
borne off the vesicles. C. bertholetiae was identified after subculture on Sabouraud dextrose agar at 45 °C. The patient died 15 days after the beginning of amphotericin
B therapy. 相似文献
4.
Maria N. Gamaletsou Nikolaos V. Sipsas Dimitrios P. Kontoyiannis 《Current fungal infection reports》2011,5(1):34-41
Invasive candidiasis (IC) is an important complication among cancer patients with neutropenia, as it is associated with significant
mortality. Despite the introduction of the new antifungals in clinical practice and their widespread use as treatment or prophylaxis,
the incidence of IC and the predominance of non-albicans Candida species remain unchanged, and mortality rates remain as high as in previous periods. New techniques have been developed to
decrease the time to Candida species identification from blood cultures. Nonculture diagnostic methods and molecular diagnostic tests for detection of
Candida are promising but have not been validated in neutropenic patients. Recently, voriconazole was proved to be as effective as
fluconazole for prophylaxis in neutropenic recipients of hematopoietic stem cell transplants and in patients with graft-versus-host
disease. Despite the lack of randomized studies of the treatment of IC among neutropenic patients, it seems that the success
rates of antifungal therapy do not differ from those in non-neutropenic patients. 相似文献
5.
6.
7.
Jiao Feng Fang Liu Fan Wu Quan De Deng Hua Mei Zeng Tao Qing Kong Jun Chen Hong Sang 《Mycopathologia》2013,176(3-4):255-258
Scutula are characteristic lesions of tinea favosa or favus; the most frequently identified causative organism is Trichophyton schoenleinii. Although scutula-like lesions were described in Microsporum gypseum infection, their presence on glabrous skin in a patient with SLE has not been reported previously. We report a case of tinea infection with scutula-like lesions caused by Microsporum gypseum in a SLE patient, who was treated with topical terbinafine cream, and the lesions resolved completely. In addition, we reviewed the reported cases about this rare clinical manifestation caused by Microsporum gypseum in the medical literature. 相似文献
8.
Paula Sampaio Marlene Santos Alexandra Correia Fábio E. Amaral Julio Chavéz-Galarza Sofia Costa-de-Oliveira António G. Castro Jorge Pedrosa Célia Pais 《PloS one》2010,5(4)
The incidence of Candida albicans infections and the relapse episodes after antifungal treatment have increased in recent decades. Recurrences are mainly due to the persistence of the original infecting strain that may present genetic and genomic rearrangements during interaction with the host, reflecting strain adaptation. In this study, four isolates recovered from a patient during recurrent candidemia episodes were genotyped by microsatellite length polymorphism (MLP) and by multilocus sequence typing (MLST) and found to be genetic variants of the same strain. Using experimental mouse infections, a progressive reduction in the virulence of the four isolates was observed, with the first two isolates more virulent than the third and fourth. Additionally, in the mouse model, the first isolate resisted host control more efficiently, resulting in higher kidney fungal burdens and necrosis as compared to the third isolate. The resolution of inflammation was delayed in mice challenged with the first isolate and the message for IFN-γ and TNF-α in the spleen was lower within the first few hours post-infection. Original and recurrent isolates also displayed different phenotypes regarding activity of secreted enzymes and response to stress agents. Overall, the comparative analysis indicated that the virulence decrease of these isolates was related to a lower ability to resist to the host anticandida effector mechanisms. We showed for the first time that C. albicans genetic variants of the same strain, sequentially isolated from an immunocompromised patient, underwent adaptations in the human host that resulted in virulence attenuation when tested in mice. 相似文献
9.
Production of uricase by Candida tropicalis using n-alkane as a substrate. 总被引:1,自引:0,他引:1
下载免费PDF全文

Production of uricase (urate oxidase, EC 1.7.3.3) by n-alkane-utilizing Candida tropicalis pK233 was studied. Although the yeast showed very low enzyme productivity under growing conditions on glucose or an n-alkane mixture (C10 to C13) (less than 2 U/g of dry cells), enzyme formation was enhanced markedly in an induction medium consisting of potassium phosphate buffer, MgSO4, uric acid, and an n-alkane mixture (47 U/g of dry cells) or glucose (21 U/g of dry cells). Of the carbon sources tested, the n-alkane mixture was the most suitable for enzyme production. Appropriate aeration also stimulated uricase formation. In addition to uric acid, xanthine, guanine, adenine, and hypoxanthine were also effective for inducing uricase. Under optimum conditions, the maximum yield of the enzyme was 91 U/g of dry cells. Uricase thus induced was localized in the microbodies of the yeast. 相似文献
10.
11.
In the experiments reported here we found that enzymatic NO synthesis in the yeast Candida tropicalis resembles the one in animal tissues with respect to the substrate arginine as well as its sensitivity to potential competitive inhibitors. Both, NO produced by the yeast's nitric oxide synthase and NO derived from an artificial donor, suppressed the formation of pseudomycelia. These results suggest to make use of NO as a tool in elucidating the mechanism controlling mycelia generation in this yeast. The apparent K(m) towards oxygen of the yeast's nitric oxide synthase (about 50 microM) was found to be high as compared to the apparent K(m) value of the yeast's respiratory chain (about 170 nM). From this observation it may be concluded that under conditions of little oxygen supply the nitric oxide synthase will unsuccessfully compete for oxygen with respiration. Therefore, the formation of mycelia spontaneously occurring in yeast cultures grown in sealed chambers can be attributed to a reduced internal NO level rather than limited respiratory activity. 相似文献
12.
Summary These experiments studied the metabolic formation of a,-dodecanedioic acid using the mutant S 76 developed from the wild strain Candida tropicalis 1230 (capable of producing large amounts of a,-dodecanedioic acid).Our results show for the first time that 12-hydroxydodecanoic acid was excreted into the medium as a free acid.n-Dodecanol and n-dodecanoic acid were also detected in the n-dodecane medium. The mutant S 76 was able to produce a,-dodecanedioic acid using either n-dodecanol or dodecanoic acid as the sole carbon source. Quantitative cahnges in the concentrations of 12-hydroxy-dodecanoic acid and other intermediates were recorded during the formation of a,-dodecanedioic acid. S 76 was rapidly able to convert large amounts of 12-hydroxy-dodecanoic acid to a,-dodecanedioic acid.The formation of a,-dodecanedioic acid from n-dodecane via the sequence n-dodecanoln-dodecanoic acid 12-hydroxy-dodecanoic acid was confirmed. 相似文献
13.
Sheetal U. Harakuni S. G. Karadesai Nadeemaktar Jamadar 《Indian journal of microbiology》2012,52(3):504-506
The present study was undertaken to investigate biofilm formation among the clinical Candida isolates from blood and cervical swabs. A total of 16 Candida blood isolates from neonates and 21 cervical isolates from pregnant women with vulvovaginitis were included in the study. Each isolate was identified to species level by various phenotypic tests. Biofilm formation was detected by colorimetric method. C. glabrata and C. albicans were the major isolates from blood and cervical swab respectively. The biofilm formation was found in 14 (87.5 %) blood isolates and only in 4 (19.1 %) cervical isolates. 相似文献
14.
Inhibition of Candida albicans Biofilm Formation by Farnesol, a Quorum-Sensing Molecule 总被引:7,自引:0,他引:7
下载免费PDF全文

Gordon Ramage Stephen P. Saville Brian L. Wickes Jos L. Lpez-Ribot 《Applied microbiology》2002,68(11):5459-5463
Farnesol is a quorum-sensing molecule that inhibits filamentation in Candida albicans. Both filamentation and quorum sensing are deemed to be important factors in C. albicans biofilm development. Here we examined the effect of farnesol on C. albicans biofilm formation. C. albicans adherent cell populations (after 0, 1, 2, and 4 h of adherence) and preformed biofilms (24 h) were treated with various concentrations of farnesol (0, 3, 30, and 300 μM) and incubated at 37°C for 24 h. The extent and characteristics of biofilm formation were then assessed microscopically and with a semiquantitative colorimetric technique based on the use of 2,3-bis(2-methoxy-4-nitro-5-sulfo-phenyl)-2H-tetrazolium-5-carboxanilide. The results indicated that the effect of farnesol was dependent on the concentration of this compound and the initial adherence time, and preincubation with 300 μM farnesol completely inhibited biofilm formation. Supernatant media recovered from mature biofilms inhibited the ability of planktonic C. albicans to form filaments, indicating that a morphogenetic autoregulatory compound is produced in situ in biofilms. Northern blot analysis of RNA extracted from cells in biofilms indicated that the levels of expression of HWP1, encoding a hypha-specific wall protein, were decreased in farnesol-treated biofilms compared to the levels in controls. Our results indicate that farnesol acts as a naturally occurring quorum-sensing molecule which inhibits biofilm formation, and we discuss its potential for further development and use as a novel therapeutic agent. 相似文献
15.
Candida tropicalis, a strain isolated from the sludge of a factory manufacturing xylose, produced a high xylitol concentration of 131 g/l from
150 g/l xylose at 45 h in a flask. Above 150 g/l xylose, however, volumetric xylitol production rates decreased because of
a lag period in cell growth. In fed-batch culture, the volumetric production rate and xylitol yield from xylose varied substantially
with the controlled xylose concentration and were maximum at a controlled xylose concentration of 60 g/l. To increase the
xylitol yield from xylose, feeding experiments using different ratios of xylose and glucose were carried out in a fermentor.
The maximum xylitol yield from 300 g/l xylose was 91% at a glucose/xylose feeding ratio of 15%, while the maximum volumetric
production rate of xylitol was 3.98 g l−1 h−1 at a glucose/xylose feeding ratio of 20%. Xylitol production was found to decrease markedly as its concentration rose above
250 g/l. In order to accumulate xylitol to 250 g/l, 270 g/l xylose was added in total, at a glucose/xylose feeding ratio of
15%. Under these conditions, a final xylitol production of 251 g/l, which corresponded to a yield of 93%, was obtained from
270 g/l xylose in 55 h.
Received: 20 April 1998 / Received revision: 29 May 1998 / Accepted: 19 June 1998 相似文献
16.
Degradation kinetics of phenol by immobilized cells of Candida tropicalis in a fluidized bed reactor 总被引:1,自引:0,他引:1
Juárez-Ramírez Cleotilde Ruiz-Ordaz Nora Cristiani-Urbina Eliseo Galíndez-Mayer Juvencio 《World journal of microbiology & biotechnology》2001,17(7):697-705
Degradation kinetics of phenol by free and agar-entrapped cells of Candida tropicalis was studied in batch cultures. The initial phenol degradation rate achieved with free cells was higher than that obtained with immobilized cells, when phenol concentrations up to 1000 mg l–1 were used. However, at higher phenol concentrations, the behaviour was quite different. The initial degradation rate of the immobilized yeast cells was about 10 times higher than that of the free cells, at a phenol concentration of 3500 mg l–1. The semicontinuous and continuous degradation of phenol by immobilized yeast cells was also investigated in a multi-stage fluidized bed reactor. The highest phenol removal efficiencies and degradation rates as well as the lowest values of residual phenol and chemical oxygen demand were obtained in the semicontinuous culture when phenol concentrations up to 1560 mg l–1 were used. 相似文献
17.
Inácio Cicero P. Diniz Madi V. Araújo Paulo Sergio R. Barros Marilane S. Andrade Melyna C. L. Lima-Neto Reginaldo G. Macêdo Danielle Patrícia C. Neves Rejane P. 《Mycopathologia》2020,185(2):395-398
Mycopathologia - Emergent fungal infections are uncommon conditions which frequently lead to death. To our knowledge, only a few cases of invasive infection by... 相似文献
18.
Mutation of Candida tropicalis by Irradiation with a He-Ne Laser To Increase Its Ability To Degrade Phenol 总被引:1,自引:0,他引:1
下载免费PDF全文

Yan Jiang Jianping Wen Xiaoqiang Jia Qinggele Caiyin Zongding Hu 《Applied microbiology》2007,73(1):226-231
Candida tropicalis isolated from acclimated activated sludge was used in this study. Cell suspensions with 5 × 107 cells ml−1 were irradiated by using a He-Ne laser. After mutagenesis, the irradiated cell suspension was diluted and plated on yeast extract-peptone-dextrose (YEPD) medium. Plates with approximately 20 individual colonies were selected, and all individual colonies were harvested for phenol biodegradation. The phenol biodegradation stabilities for 70 phenol biodegradation-positive mutants, mutant strains CTM 1 to 70, ranked according to their original phenol biodegradation potentials, were tested continuously during transfers. Finally, mutant strain CTM 2, which degraded 2,600 mg liter−1 phenol within 70.5 h, was obtained on the basis of its capacity and hereditary stability for phenol biodegradation. The phenol hydroxylase gene sequences were cloned in wild and mutant strains. The results showed that four amino acids were mutated by irradiation with a laser. In order to compare the activity of phenol hydroxylase in wild and mutant strains, their genes were expressed in Escherichia coli BL21(DE3) and enzyme activities were spectrophotometrically determined. It was clear that the activity of phenol hydroxylase was promoted after irradiation with a He-Ne laser. In addition, the cell growth and intrinsic phenol biodegradation kinetics of mutant strain CTM 2 in batch cultures were also described by Haldane's kinetic equation with a wide range of initial phenol concentrations from 0 to 2,600 mg liter−1. The specific growth and degradation rates further demonstrated that the CTM 2 mutant strain possessed a higher capacity to resist phenol toxicity than wild C. tropicalis did. 相似文献
19.
Eun Jin Park Joon Young Song Min Ju Choi Ji Ho Jeon Jah-yeon Choi Tae Un Yang Kyung Wook Hong Ji Yun Noh Hee Jin Cheong Woo Joo Kim 《The Korean journal of parasitology》2014,52(4):425-428
A 45-year-old-male who had underlying ulcerative colitis and presented with fever and dry cough. Initially, the patient was considered to have invasive aspergillosis due to a positive galactomannan assay. He was treated with amphotericin B followed by voriconazole. Nevertheless, the patient deteriorated clinically and radiographically. The lung biopsy revealed eosinophilic pneumonia, and ELISA for Toxocara antigen was positive, leading to a diagnosis of pulmonary toxocariasis. After a 10-day treatment course with albendazole and adjunctive steroids, the patient recovered completely without any sequelae. Pulmonary toxocariasis may be considered in patients with subacute or chronic pneumonia unresponsive to antibiotic agents, particularly in cases with eosinophilia. 相似文献
20.
Candida tropicalis isolated from acclimated activated sludge was used in this study. Cell suspensions with 5 x 10(7) cells ml(-1) were irradiated by using a He-Ne laser. After mutagenesis, the irradiated cell suspension was diluted and plated on yeast extract-peptone-dextrose (YEPD) medium. Plates with approximately 20 individual colonies were selected, and all individual colonies were harvested for phenol biodegradation. The phenol biodegradation stabilities for 70 phenol biodegradation-positive mutants, mutant strains CTM 1 to 70, ranked according to their original phenol biodegradation potentials, were tested continuously during transfers. Finally, mutant strain CTM 2, which degraded 2,600 mg liter(-1) phenol within 70.5 h, was obtained on the basis of its capacity and hereditary stability for phenol biodegradation. The phenol hydroxylase gene sequences were cloned in wild and mutant strains. The results showed that four amino acids were mutated by irradiation with a laser. In order to compare the activity of phenol hydroxylase in wild and mutant strains, their genes were expressed in Escherichia coli BL21(DE3) and enzyme activities were spectrophotometrically determined. It was clear that the activity of phenol hydroxylase was promoted after irradiation with a He-Ne laser. In addition, the cell growth and intrinsic phenol biodegradation kinetics of mutant strain CTM 2 in batch cultures were also described by Haldane's kinetic equation with a wide range of initial phenol concentrations from 0 to 2,600 mg liter(-1). The specific growth and degradation rates further demonstrated that the CTM 2 mutant strain possessed a higher capacity to resist phenol toxicity than wild C. tropicalis did. 相似文献