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Antony G Saralaya V Bhat GK Shivananda PG 《Indian journal of medical microbiology》2007,25(3):241-244
PURPOSE: The purpose of the present study was to determine the degree of expression of virulence factors such as adherence, cell surface hydrophobicity (CSH) and production of proteinase by different morphological forms of Candida albicans causing oral candidiasis in human immunodeficiency virus (HIV)-infected individuals. METHODS: C. albicans 3153A and two strains isolated from oral thrush in HIV infected individuals were induced to undergo phenotypic switching by exposure to UV light and the degree of expression of virulence factors by the different morphological forms was studied. RESULTS: Three different morphological forms of C. albicans were obtained namely, star (S), wrinkled (W) and ring (R) types from the original smooth (O) variety. It was found that proteinase production was greatest with the W type followed by the R type and O type. The S type produced the least proteinase. Expression of cell surface hydrophobicity and adherence was greatest in the O type followed by the R and then the W type and finally the S type. CONCLUSIONS: The differential expression of virulence factors occurs with different phenotypic forms of C. albicans and this may provide a particular morphological type with a distinct advantage over other types in causing candidiasis. 相似文献
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Kasun M. Thambugala Hiran A. Ariyawansa Yan-Mei Li Saranyaphat Boonmee Sinang Hongsanan Qing Tian Chonticha Singtripop D. Jayarama Bhat Erio Camporesi Ruvishika Jayawardena Zuo-Yi Liu Jian-Chu Xu Ekachai Chukeatirote Kevin D. Hyde 《Fungal Diversity》2014,68(1):105-158
The type specimens or representative specimens of the potentially dothidealean genera Bagnisiella, Botryochora, Coccostromella, Columnosphaeria, Delphinella, Dictyodothis, Discosphaerina, Dothidea, Dothiora, Endodothiora, Jaffuela, Mycoporis, Omphalospora, Pachysacca, Plowrightia, Saccothecium, Stylodothis, Sydowia and Yoshinagaia were examined while, fresh specimens of Aureobasidium pullulans, Dothidea insculpta, Plowrightia ribesia and Saccothecium sepincola were made from Italy and Thailand. An introduction and the history of these genera, their family placement, morphology, and molecular phylogeny are provided. Morphology plus GenBank data are used to provide a systematic treatment of Dothideales. Phylogenetic analysis of LSU, SSU and ITS gene regions was carried out and in the resulting phylogenetic tree the taxa cluster in two clades with high bootstrap support. Clade A comprises Dothideaceae, the family type of Dothideales. The family Dothioraceae is not recognized as a distinct family and is synonymized under Dothideaceae. Neocylindroseptoria is introduced to accommodate Cylindroseptoria pistaciae as it forms a well-supported distinct clade in Dothideaceae. Clade B comprises Aureobasidium, Kabatiella, Pseudoseptoria, Saccothecium and Selenophoma species and Columnosphaeria fagi, for which we propose a new family, Aureobasidiaceae. The recently introduced Sydowia eucalypti also clustered within Clade B and therefore based on morphology and molecular phylogeny a new genus Pseudosydowia is introduced for Sydowia eucalypti. Celosporium laricicola is separated in a distinct clade, and therefore it is placed in Dothideales, genera, incertae sedis. The genera Bagnisiella, Botryochora, Coccostromella, Jaffuela, Lucidascocarpa, Mycoporis, Omphalospora, Pachysacca and Yoshinagaia are excluded from Dothideales and their placements are discussed. 相似文献
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Lenihan DJ Rosenbaum AF Burwinkel P Tseng CY Bhat G Wagoner L Walsh RA Gerson MC 《American heart journal》1999,137(5):942-948
BACKGROUND: Cardiac allograft arteriopathy often limits long-term survival in transplantation recipients but has been difficult to detect by standard diagnostic methods. Because of the diffuse nature of transplantation coronary disease, we postulated that a lung/heart ratio during dipyridamole thallium imaging might better predict arteriopathy-related complications than diagnostic methods that detect discrete luminal stenoses. METHODS AND RESULTS: Sixty-six unselected heart transplantation recipients were evaluated with annual coronary arteriograms, endomyocardial biopsy, and intravenous dipyridamole thallium testing (initial study group). The mean lung/heart ratio on an anterior planar image was 0.40 for all patients; therefore <0.40 was arbitrarily defined as normal. After October 1992, 98 patients were tested (validation study group) and a lung/heart ratio cutoff of 0.40 was evaluated prospectively. Coronary end points were defined as (1) at least 1 coronary artery stenosis >/=50% of the luminal diameter, (2) sudden cardiac death, and (3) acute myocardial infarction. Stepwise logistic regression analysis was performed to identify independent predictors of future coronary end points. For the initial study group, the lung/heart ratio on the first annual thallium study was the only independent predictor of subsequent cardiac end points (0.47 +/- 0.13 [SD] with end points vs 0.38 +/- 0.11 without end points, P <.05). For the validation study group, independent predictors of subsequent coronary events included the lung/heart ratio and the radionuclide left ventricular ejection fraction. No patient with a lung/heart ratio <0.40 and a left ventricular ejection fraction >/=0.50 developed a cardiac event during 21 +/- 11 months of follow-up. CONCLUSIONS: A lung/heart ratio >/=0.40 on dipyridamole thallium testing is a sensitive predictor of coronary events after heart transplantation. Patients with heart transplantion who have a lung/heart ratio <0.40 and normal systolic left ventricular function are at low risk for subsequent coronary events and may not require annual surveillance by coronary arteriography. 相似文献
79.
Vitamin B12 absorption--a study of intraluminal events in control subjects and patients with tropical sprue. 下载免费PDF全文
The intraluminal fate of orally administered radioactive vitamin B12 has been studied in control subjects with normal vitamin B12 absorption and those with vitamin B12 malabsorption due to tropical sprue. In control subjects 1 to 21% of the dose was bound to sedimentable material and 37 to 75% was bound to immunoreactive intrinsic factor. In subjects with vitamin B12 malabsorption due to tropical sprue, the results were identical with the control subjects. Bacteriological studies showed a statistically significant correlation between both the number of flora in the jejunum and the number of bacteroides in both the jejunum and ileum and vitamin B12 malabsorption. In patients with tropical sprue who have normal intrinsic factor secretion, the vitamin B12 absorptive defect is not due to binding of the vitamin to bacteria or to alteration to the intrinsic factor vitamin B12 complex in the intestinal lumen. The lesion appears to be one of the mucosal cell receptors or of the cells themselves, possibly caused by bacterial toxins. 相似文献
80.
Parakh K Thombs BD Bhat U Fauerbach JA Bush DE Ziegelstein RC 《The American journal of medicine》2008,121(11):1015-1018