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1.
We identified the etiological agents responsible for two fatal cases of rhinocerebral mucormycosis with the classical risk factor for uncontrolled type II diabetes mellitus. Their initial symptoms did not point immediately to the suspicion of mucormycosis. Case 1, caused by Rhizopus microsporus var. oligosporus, was a 52-year-old man who presented with a painful pimple on his nose, which evolved with swelling, erythema, and a central pustule on his right hemiface suspected to be cellulitis. After 7 days of antibiotic treatment, the patient worsened with signs of sepsis and the lesion evolved to necrosis involving all his right face. Case 2, caused by Rhizopus microsporus var. rhizopodiformis, was a 57-year-old woman placed on continuous therapy with azathioprine and corticoids after a renal transplant due to chronic arterial hypertension and uncontrolled type II diabetes mellitus. Because she was suspected to have sepsis, the patient was treated with broad-spectrum antibiotics and mechanical ventilation, yet she deteriorated. Because Candida spp. were isolated from urine and a BAL, she was treated with fluconazole for 10 days, then substituted by caspofungin. Two weeks later, she presented with exophthalmus of the left eye that was surrounded by a large inflammatory and necrotic area. Both patients were the diagnosed with mucormycosis via direct microscopy of necrotic material prior to their death.  相似文献   

2.
Although the extensive use of Aspergillus-active antifungals has been recently associated with an increase in zygomycosis in several cancer centers, the frequency of this opportunistic mycosis began to rise earlier, since the mid 1990s. The reasons for that emergence are unclear. Recent evidence suggests that endosymbiotic bacteria of Rhizopus species produce toxins that enhance fungal pathogenicity. We postulate that, although Zygomycetes appear equally ubiquitous and virulent to Aspergillus, zygomycosis was rare in the past in immunosuppressed patients specifically because of the widespread use of antibacterials in this patient population. Such use may have resulted in inhibition of endosymbiotic, toxin-producing bacteria and led indirectly in attenuation of Zygomycetes virulence. Thus, the growing rates of antimicrobial resistance over the past decade selected for multidrug-resistant endosymbiotic bacteria of Zygomycetes, which could facilitate the emergence of zygomycosis. This hypothesis, if true, will be the first paradigm of modulation of virulence of opportunistic fungi by antibacterials.  相似文献   

3.
报道1例由小孢根霉变种导致的皮肤毛霉病.患者女,30岁.因患急性早幼粒细胞白血病,化疗后继发口腔颌面部小孢根霉变种感染,表现为发热、右侧颊黏膜水肿,皮损中央溃疡、焦痂,周边组织炎性水肿,以面颊部、颌下区为中心明显肿胀,逐渐累及右侧颈部及右下颌,进行性加重.坏死组织涂片镜检显示有粗大、无分隔直角菌丝,真菌学检查鉴定为小孢根霉,分子测序证实为小孢根霉变种.给予两性霉素B、伊曲康唑静脉滴注和手术清创,坏死组织连续3次真菌培养均未培养出小孢根霉变种,患者体温逐渐恢复正常,治疗2周后颔面部肿胀明显减退,浅表淋巴结未触及肿大,4周后额部及右眼睑肿胀已完全消退,伤口结痂愈合.随访2 a,右侧颌下可见长约2 cm手术疤痕,未见皮肤毛霉病复发.  相似文献   

4.
The present investigation presents evidence that rhizoferrin, a novel polycarboxylate or complexone-type siderophore, originally isolated from Rhizopus microsporus, represents the common siderophore within the Zygomycetes. Thus, rhizoferrin could be detected by HPLC analysis in various families of the Mucorales, e.g., Rhizopus microsporus var. rhizopodiformis, Mucor mucedo and Phycomyces nitens (Mucoraceae), Chaetostylum fresenii and Cokeromyces recurvatus (Thamnidiaceae), Cunninghamella elegans and Mycotypha africana (Choanephoraceae) and Mortierella vinacea (Mortierellaceae) and in Basidiobolus microsporus (Entomophthorales). The function of rhizoferrin as a siderophore in the fungus R. microsporus var. rhizopodiformis was demonstrated by time- and concentration-dependent uptake of [55Fe]-labelled rhizoferrin, yielding saturation kinetics with values of Km = 8 microM and V(max) = 1.2 nmol min-1 (mg dry wt)-1.  相似文献   

5.
Zygomycoses are opportunistic infections caused by the Mucorales fungi. They are typically seen in immunosuppressed patients. The incidence of zygomycosis cases seems to be increasing. We report on zygomycosis in a pediatric, female stem-cell-transplant recipient. This case report underlines the difficulty of taking care of patients with zygomycosis. In fungal infections of immunosuppressive patients on broad-coverage antibiotics, foci of skin necrosis are unique and typical for zygomycoses, and may be helpful in this challenging diagnosis.  相似文献   

6.
Fungal isolates belonging to four Rhizopus species were screened for the presence of double-stranded RNA (dsRNA) molecules. Five (two R. stolonifer, two R. microsporus, and one R. oryzae) of the 27 isolates examined harboured such genetic elements. Electrophoresis of the nucleic acids revealed five RNA patterns, with 1-5 discrete dsRNA bands. The molecular sizes corresponding to these bands were 2.2-14.8 kb. Gel electrophoresis of purified virus-like particles (VLPs) indicated only one capsid of similar size in all virus-harbouring strains; when investigated by electron microscopy, they were found to be polyhedral VLPs 40 nm in diameter. In one of the R. microsporus isolates an uncapsidated large dsRNA segment (14.8 kb) was observed. No phenotypic differences were observed between uninfected and virus-harbouring Rhizopus isolates.  相似文献   

7.
We investigated the potential of 33 different zygomycete isolates to cause cerebral disease following the intranasal instillation of their spores into ketotic rabbits with alloxan induced diabetes. The isolates represented six thermotolerant species of Rhizopus (R. arrhizus, R. chinensis, R. microsporus, R. oligosporus, R. oryzae, and R. rhizopodiformis), Absidia corymbifera, Cunninghamella bertholletiae, and Rhizomucor pusillus. All 13 isolates of the thermotolerant Rhizopus species proved to be cerebral pathogens as confirmed by culture and histopathology. One isolate of R. oligosporus and one isolate of R. rhizopodiformis, however, were less pathogenic than isolates of other Rhizopus species tested. Cerebral pathogenicity was noted with 2 of 5 isolates of Rh. pusillus and only 1 of 13 A. corymbifera isolates. Two thermotolerant C. bertholletiae cultures, recovered from human lesions, did not cause either cerebral or pulmonary disease in ketotic rabbits. The incidence of pulmonary zygomycosis caused by the isolates of the species of the four genera under study was as follows: Rhizomucor 24%, Rhizopus 22%, Absidia 9%, and Cunninghamella 0%. This study confirms the pathogenic potential of the thermotolerant species of Rhizopus to cause cerebral zygomycosis in ketotic diabetic rabbits and also revealed the potential of Rh. pusillus and A. corymbifera occasionally to cause the same disease in animals and humans.  相似文献   

8.
Sixty-nine nonmetrical morphological variants of the cranium have been studied in six samples of non-tribal, state populations in India, and their incidence reported. Using C.A.B. Smith’s angular transformation of frequencies, the multivariate Thetasquare distances and their respective standard deviations have been presented. On the basis of nonmetrical cranial variation, it is clear that the samples from Uttar Pradesh, Andhra Pradesh and Bihar are closer to each other but distant from Madhya Pradesh, Karnataka and Maharashtra. On the other hand, Karnataka and Maharashtra samples are quite close to each other and both, in turn, are comparatively closer to Madhya Pradesh than to Uttar Pradesh, Andhra Pradesh and Bihar. Madhya Pradesh sample emerges as the most divergent group among the six population samples studied. This, in general, is in conformity with the picture that emerges from various analysis of morphometric and other biological data on various populations of India.  相似文献   

9.
We report a case of cutaneous zygomycosis caused by Rhizopus arrhizus in a surgical wound following colostomy. The patient was a diabetic and in addition presented others risk factors. Zygomycosis was suspected when a necrotic wound surface appeared in the appropiate clinical setting. Diagnosis was confirmed on a combined histological and microbiological study. Extensive surgical resection, high doses of amphotericin B and treatment of the underlying conditions permitted the control of the infection.  相似文献   

10.
Lipase biosynthesis by the fungus Rhizopus microsporus UzLT-1 was investigated. Under certain conditions the fungus could produce two forms of extracellular lipases. The paper describes the process of purification of the enzyme L-I,N- and C-terminal amino acids of the lipases have been determined. Identity of terminal amino acids of both enzymes has been demonstrated. It has been shown that both forms of lipase from Rhizopus microporus hydrolyze predominantly alpha-ester bonds.  相似文献   

11.
【目的】斯氏按蚊Anopheles stephensi是亚洲东南部城市人体疟疾的主要媒介,印度12%的疟疾病例由其引起。本实验研究了印度中部Madhya Pradesh地区东北部的疟疾强化控制(EMCP)区和非强化控制(非EMCP)区斯氏按蚊的基因流。在EMCP区,由于采用了各种疟疾防控措施因而疟疾病例首先降低,但是很快回升,说明总的疟疾风险维持稳定。【方法】应用7个微卫星位点,对印度中部Madhya Pradesh地区东北部的4个EMCP区和非EMCP区采集的斯氏按蚊进行基因分型,以分析各种群参数。【结果】发现各标记在所有种群中表现出高度的多态性。在两区间未发现很大的遗传多样性。观察到EMCP区的东部种群(FST=0.0485,RST=0.1112)比非EMCP区的北部种群(FST=0.020,RST=0.0145)具有较高的遗传分化,在EMCP区和非EMCP区之间观察到较高的基因流(12.90,6.16,5.06和2.38)。RST的灵敏度高于FST,说明分化可能是由于突变而非遗传漂变引起的。【结论】本研究表明,在EMCP区和非EMCP区内以及EMCP区和非EMCP区之间存在很高的基因流。基因流水平高以及抗虫性的发展似乎是EMCP区和非EMCP区疟疾病例发生增加的重要原因。  相似文献   

12.
Mucormycosis is an uncommon opportunistic infection by filamentous fungi that usually develops in immmunocompromised patients. Most individuals have an underlying systemic disease, such as diabetes mellitus, malignancy, uraemia, burns, renal transplant recipients and those on corticosteroid and immunosuppressive therapy. Many cases of primary renal zygomycosis with lungs serving as the portal of entry have been reported from this region. We describe two autopsy cases of renal zygomycosis where bladder appeared to be the portal of entry for the fungus.  相似文献   

13.
Madhya Pradesh is the major soybean contributor in India. The taxonomy of nitrogen fixing bacteria forming symbiotic associations with leguminous plants has been deeply changed in recent years. The use of very sensitive and accurate molecular methods has enabled the detection of large rhizobial diversity. Molecular biotyping and characterization the Bradyrhizobium, isolates from eleven varieties of soybean from agricultural field of Sehore district of Madhya Pradesh is done using 16S rDNA typing. Bradyrhizobia were identified genetically by determining the %Guanine plus Cytosine content of the whole genome, followed by 16S rDNA-RFLP analysis % Guanine plus Cytosine content of all the Bradyrhizobium isolates reflects similarity at generic level among all Bradyrhizobial isolates. Restriction Fragment Length Polymorphism (RFLP) further showed a considerable level of genetic diversity among the Bradyrhizobial isolates. PCR-RFLP of 16S rDNA supported existence of two divergent groups among indigenous Bradyrhizobial isolates, at similarity level of 66, and 75 and 74% of similarity within the group. The technique used was helpful in characterizing Bradyrhizobium isolates to be used as inoculants for improving productivity of agricultural land of Madhya Pradesh (India).  相似文献   

14.

Background  

Subcutaneous zygomycosis is a chronic infection caused by fungus of the order Entomophthorales. It can have varying presentations and presents in the nose and face area with gradually progressing subcutaneous swelling that may be difficult to diagnose unless a strong suspicion of fungal involvement is maintained. We present a case of subcutaneous zygomycosis in a 35-year-old male patient, resident of a North Indian state. The patient was diagnosed to be suffering from subcutaneous zygomycosis, the causative agent being Basidiobolus ranarum identified on culture and lactophenol cotton blue mount preparation. He responded well to treatment with Itraconazole and Terbinafine and is asymptomatic on follow-up.  相似文献   

15.
Rhizonin is a hepatotoxic cyclopeptide isolated from cultures of a fungal Rhizopus microsporus strain that grew on moldy ground nuts in Mozambique. Reinvestigation of this fungal strain by a series of experiments unequivocally revealed that this "first mycotoxin from lower fungi" is actually not produced by the fungus. PCR experiments and phylogenetic studies based on 16S rRNA gene sequences revealed that the fungus is associated with bacteria belonging to the genus Burkholderia. By transmission electron microscopy, the bacteria were localized within the fungal cytosol. Toxin production and the presence of the endosymbionts were correlated by curing the fungus with an antibiotic, yielding a nonproducing, symbiont-free phenotype. The final evidence for a bacterial biogenesis of the toxin was obtained by the successful fermentation of the endosymbiotic bacteria in pure culture and isolation of rhizonin A from the broth. This finding is of particular interest since Rhizopus microsporus and related Rhizopus species are frequently used in food preparations such as tempeh and sufu.  相似文献   

16.
Legume crops in Central India, the main soybean production area of the country, may suffer from yellow mosaic disease caused by the Mungbean yellow mosaic India virus (MYMIV). MYMIV is transmitted by the sweet potato whitefly, Bemisia tabaci (Gennadius), which is a species complex composed of various genetic groups. This vector species harbors different endosymbionts among regional strains and among individuals. To elucidate fundamental aspects of this virus vector in the state of Madhya Pradesh, the infection status of the symbionts and the virus in whiteflies was studied. A polymerase chain reaction (PCR) survey of the whiteflies collected in Madhya Pradesh found four secondary endosymbionts, Arsenophonus, Hemipteriphilus, Wolbachia, and Cardinium, in addition to the primary endosymbiont Portiera. Arsenophonus and Hemipteriphilus were highly infected but the infection rates of Wolbachia and Cardinium were low. MYMIV was detected in whitefly populations collected from various host plants in Madhya Pradesh. The whitefly populations belonged to the Asia I and II genetic groups; several different Asia II populations were also distributed. Specific relations were not observed among symbiont infection status, virus infection, and the whitefly genetic groups in the populations of Madhya Pradesh, though Cardinium was highly detected in the Asia II-1 group. New primers, which can be used for PCR template validation and for discriminating two phylogenetically close endosymbionts, were designed.  相似文献   

17.
Of 199 fungal cultures isolated from some of the common cereals collected from different parts of Uttar Pradesh and Madhya Pradesh, 70 produced toxic metabolites. Of the 70 fungi isolated, 59 produced toxins which caused visible lesions in livers, kidneys, and spleens but did not cause mortality. Toxicity, graded in terms of the mortality rate and the extent of lesions in livers, kidneys, and spleens, was found to be highest in various species of Aspergillus (40%), followed by Chaetomium spp. (31%).  相似文献   

18.
A cultivation procedure for the preparation of a new tempeh-like fermented soybean containing a high level of gamma-aminobutyric acid was developed. Steamed soybeans were incubated aerobically with Rhizopus microsporus var. oligosporus IFO 8631 for 20 h, and then anaerobically incubated for 5 h by replacement of the atmosphere with nitrogen. The GABA content in the aerobically fermented soybeans was about 30 mg per 100 g dry fermented soybeans, while the anaerobically cultivation was about 370 mg/100 g dry fermented soybeans. The incubation with several strains of Rhizopus species showed that all of R. microsporus var. oligosporus and R. oryzae examined accumulated GABA in the anaerobically fermented soybeans. In particular, R. microsporus var. oligosporus IFO 32002 and IFO 32003 showed the highest content of GABA (1,740 mg/100 g dry fermented soybeans and 1,500 mg/100 g dry fermented soybeans, respectively). Moreover, the free protein amino acids increased greatly in the fermented soybeans during the anaerobic cultivation.  相似文献   

19.
This is a literature review of 361 opportunistic fungal infections caused by the Zygomycetes. The clinical and laboratory diagnosis, pathogenesis, management, treatment, and outcome of infection are discussed. The Zygomycetes are a group of opportunistic fungi (orders Mucorales and Entomophthorales) which cause severe infections which may be fatal. Early clinical recognition, prompt diagnostic procedures, control of underlying disease and treatment with high doses of amphotericin B and aggressive surgery increases survival in an otherwise lethal infection.  相似文献   

20.
Desmids from Pachmarhi,Madhya Pradesh,India   总被引:1,自引:0,他引:1  
An illustrated account is given of 68 desmids from streams running below Pachmarhi plateau in Madhya Pradesh, India, Two varieties of Euastrum are new to science.  相似文献   

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