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Rhinocerebral mucormycosis (phycomycetes), a human fungal disease with oral and perioral findings, has an extremely high morbidity and mortality. The disease is most frequently seen in patients with poorly controlled diabetes. The symptoms, findings, and treatment of rhinocerebral mucormycosis are discussed, and two case histories are presented.
A 61-year-old man with a ruptured aneurysm of the anterior communicating artery developed hemorrhagic cerebral infarction 22 days after an operation associated with occlusion of the right angular artery. Angiograms further revealed sequential changes of intracranial vessels including progressive obstructions of the right anterior and middle cerebral arteries and four aneurysms on the left pericallosal artery. Subsequently, the patient became comatose and died. At autopsy the newly formed aneurysms originating from the left pericallosal artery were of fungal (Phycomycetes) origin and numerous nonseptate, branching hyphae were also seen in the obstructed cerebral arteries. Intracranial fungal aneurysms are reviewed in the literature and the pathogenesis in the present case is discussed.
Hyphomycetous (Aspergillus fumigatus) and Phycomycetous (Mucor hiemalis) moulds were cultivated in vitro at room temperature (28 + 20 degrees C) to examined their growth and biomass production on waste banana peel agar (BPA) and broth (BPB) using commercial malt extract agar (MEA) and broth (MEB) as control. The moulds grew comparatively well on banana peel substrates. No significant difference (p > 0.05) in radial growth rates was observed between moulds cultivated on PBA and MEA, although growth rates on MEA were slightly better. Slight variations in sizes of asexual spores and reproductive hyphae were also observed between moulds grown on MEA and BPA. Smaller conidia and sporangiospores, and shorter aerial hyphae (conidiophores and sporangiophores) were noticed in moulds grown on BPA than on MEA. The biomass weight of the test moulds obtained after one month of incubation with BPB were only about 1.8 mg and 1.4 mg less than values recorded for A. fumigatus and M. hiemalis respectively, grown on MEB. The impressive performance of the moulds on banana peel substrate may be attributed to the rich nutrient (particularly the crude protein 7.8% and crude fat 11.6% contents) composition of banana peels. The value of this agricultural waste can therefore be increased by its use not only in the manufacture of mycological medium but also in the production of valuable microfungal biomass which is rich in protein and fatty acids.
An autopsy study of 60 patients with fungal infections of the heart was undertaken. The patients ranged in age from 2 months to 79 years. Fifteen of the patients had undergone cardiac surgery; neoplasms were found in 13, renal failure in eight, bacterial infections in five, liver disease in five, gastrointestinal disorders in five, and immune disease in four; two had been intravenous drug abusers; other miscellaneous disorders were observed in three. The fungal infection was limited to the myocardium in 27 patients and to the endocardium in 17 patients. Myocardium and endocardium were involved in nine patients and pericardium and myocardium in five; two patients had pericarditis alone. The most frequent organism was Candida (62 per cent). Aspergillus (12 per cent) and Phycomycetes (12 per cent) were also found frequently. In 51 patients (85 per cent) other deep organs, usually lung, kidney, brain, or spleen were involved. Cultures for fungus had been positive in 26 patients prior to death, and postmortem cultures were positive in 29 patients. Patients who had undergone cardiac surgery had a higher incidence of endocarditis (93 per cent), with Candida (53 per cent) being the most frequent cause. Patients who had received antineoplastic drugs, antibiotics, or corticosteroids had a higher incidence of myocarditis (79 per cent), again most often due to Candida (60 per cent).
In search of an easy and quick method for the diagnosis of fungal and Acanthamoeba infections of the eye, the authors have used calcofluor white (CFW), a fluorescent brightener with marked affinity for chitin and cellulose which are present in the cell walls of fungi and cysts of Acanthamoeba. Paraffin-embedded tissues containing mycotic organisms were stained with CFW and examined under a fluorescent microscope. Several fungi such as Candida sp, Aspergillus sp, Phycomycetes, Fusarium solani, Histoplasma capsulatum, Cryptococcus neoformans, Rhinosporidium seeberi, and others were studied. Trephine corneal biopsy specimens (2 mm) and methanol-fixed corneal scrapings containing Acanthamoeba sp were also examined. The walls of fungi and Acanthamoeba cysts stained bright greenish white in contrast to the reddish-orange background of the supporting tissues. The results demonstrate that the CFW method is a highly reliable and rapid technique for identification of mycotic organisms as well as cysts of Acanthamoeba. This method may also be applied in surgical pathology when performing frozen sections, as well as cytologic examination of corneal smears, vitrectomy specimens, and others.
A low-cost single-stage laboratory process combining fungal dehydration and lipid extraction was compared with a traditional two-stage method employing freeze-drying and subsequent mechanical disruption in the presence of solvent. The ability of a number of organic solvents to form hetero-azeotropes with water was exploited. Chloroform, cyclohexane and hexane were assessed in their abilities to both dry and extract lipid from the oleaginous phycomycete Mortierella alpina (ATCC 32222). Drying rate and lipid extraction were maximised under conditions that prevented fungal agglomeration. The total processing time was limited by the rate of dehydration rather than by the rate of lipid extraction. In all cases azeotropic distillation facilitated a greater rate of dehydration than was possible with freeze-drying. A consequent reduction in overall processing time was observed. Uniquely, both the solvent used and the mode of mixing employed controlled the morphology of the aggregates formed during distillation. In combination with mild mixing chloroform discouraged agglomeration whereas cyclohexane and hexane promoted aggregation. Successful lipid extraction was dependent on the use of dry biomass rather than on the application of heat to effect distillation. Neither the application of heat nor the solvent employed had any significant effect on the lipid composition of the extracted oil.
A fungal endophytic isolate, camptothecin, has been isolated from the inner bark of the plant Nothapodytes foetidafrom the Western coast of India. The fungus, which belongs to the family Phycomycetes, produced the anticancer drug lead compound camptothecin (1) when grown in a synthetic liquid medium (Sabouraud broth) under shake flask and bench scale fermentation conditions. Compound 1 was identified by means of chromatographic and spectroscopic methods. It was also compared with an authentic example for its biological activity against a number of human cancer cell lines. Isolation of an organism producing 1 and its fermentation may, in the future, provide an easily accessible source for the production of this anticancer drug precursor molecule.
Lysine synthesis in prokaryotes, some phycomycetes and higher plants starts with the condensation of L-aspartate-beta-semialdehyde (L-ASA) and pyruvate into dihydrodipicolinic acid. The enzyme that catalyses this step, dihydrodipicolinate synthase (DHDPS), is inhibited by the end-product lysine and is therefore thought to have a regulatory control on lysine synthesis. We have cloned and sequenced an Arabidopsis thaliana DNA fragment containing 900 bases upstream of the dhdps coding sequence. A transcriptional fusion of this fragment with the beta-glucuronidase reporter gene (uidA. Gus) was used to study the transcription properties of this promoter fragment (DS). No lysine-induced repression on transcription could be detected. Expression of DS-Gus activity in transformed Arabidopsis thaliana and Nicotiana tabacum was found to be cell type-specific. In the vegetative parts of the plant, GUS activity was located in meristems and young vasculature of roots, in vasculature of stem and leaves and in the meristems of young shoots. In flowers, high expression was found in the carpels, style, stigma, developing embryos, tapetum of young anthers and pollen. We demonstrated that the Arabidopsis DS promoter can direct its cell type-specific expression in a heterologous plant, Nicotiana tuabacum. The importance of transcriptional regulation of the dhdps gene, and in more general genes involved in amino acid biosynthesis, is discussed.
A review of the fungi associated with soybean seeds, pods, or flowers was conducted in North America. Species of Deuteromycetes are the most common fungi in each of the soybean flower organs followed by the Ascomycetes and Phycomycetes which comprise about one-fourth of the total mycoflora. Eighty genera and about 135 or more species occur in seeds, pods, or flowers. With regard to numbers of taxa from separate mycofloras, 63 genera and about 108 or more species occur in seeds, 65 genera and about 88 or more species occur in pods, and 36 genera and approximately 47 or more species occur in flowers. Most of the fungi which occur in flowers can be cultured from pods, and the majority of those fungi occur in seeds. Methods for and a key are provided for the identification of the 30 most important selected fungi.
Infections by members of the Phycomycetes class of fungi typically arise in patients with substantial underlying immunosuppression. Several clinical presentations, including that of gangrenous cellulitis, have been described. In the pediatric population, critically ill premature newborns and older children with underlying hematopoietic malignancies and/or bone marrow transplantation are affected. Presentation in children with solid organ transplants is rare. Successful therapy for this condition includes aggressive debridement of infected tissue and systemic administration of amphotericin B.
The Phycomycete, Coelomomyces psorophorae Couch, 1945, was found in the south of France in the salt marsh mosquito Aedes detritus (Haliday, 1833). The fungus invades the ovarioles but leaves the follicules intact. At high magnification, (using a scanning electron microscope), the crater-form punctuations adorning the sporangium were seen to result from openings (ostioles) of the network of small canals that traverse the external wall.
Two cases of Basidiobolomycosis caused by species of the order Entomophthorales are discussed with the report on lymph node involvement by B. haptosphorus. A clearer aetiological classification of the diseases caused by various agents belonging to the class Phycomycetes is preferred in view of the distinct clinical entities produced by them. Involvement of the lymph nodes is also an evidence that the disease produced by B. haptosporus is not restricted to subcutaneous tissue. A routine lymph node biopsy with mycological studies of the node is suggested in such cases.
The incidence of mucormycosis, defined as systemic infection caused by fungi of the class Phycomycetes has been increasing over the past 2 decades, especially in profoundly immunocompromised hosts. We report a new case in a patient presenting with post-transplant high-grade non-Hodgkin's lymphoma who received a prolonged treatment with voriconazole and caspofungin for an invasive pulmonary aspergillosis. Definite diagnosis of mucormycosis was made by liver biopsy of nodules mimicking progressive lymphoma. The patient died 1 week after the diagnosis of mucormycosis despite the administration of liposomal amphotericin B. The role of voriconazole and caspofungin in the emergence of mucormycosis is discussed.
Phycomycosis is seen most frequently in association with states of immunologic disturbance or hormonal imbalance. Several characteristic sites of infection with Phycomycetes are recognized, but mediastinal involvement has not been previously reported. A case of mediastinal granuloma due to Rhizopus species is described, and comparisons are made with other infections of similar histologic appearance.
Mucormycosis is an often-fatal opportunistic fungal infection caused by members of the class Zygomycetes (Phycomycetes), order Mucorales. Most cases are diagnosed by histologic examination, through the identification of mucormycotic hyphae in infected tissues. Chronic debilitating conditions accompanied by acidosis such as diabetes mellitus, as well as leukemia, lymphoma, and immunodeficient states, predispose to the development of this type of opportunistic infection. This report describes a hitherto undescribed finding, the presence of structures consistent with sporangia in tissue sections, in a case of pulmonary mucormycosis occurring in a nondiabetic patient with metabolic acidosis secondary to chronic salicylate poisoning.
We report on 44 cancer patients who had serious infections with unusual fungal pathogens and who were cared for at our cancer center between 1974 and 1986. Twelve different fungal species accounted for these infections, including Trichosporon beigelii, Fusarium species, Geotrichum candidum, Curvularia species, Drechslera species, Penicillium species (but not Penicillium marneffei), Rhodotorula rubra, Pseudallescheria boydii, Pichia farinosa, Torulopsis pintolopesii, Saccharomyces cerevisiae, and Cunninghamella bertholletiae. Skin lesions were noted in seven patients, and sinusitis occurred in four. Twenty-four patients had disseminated infection, 12 had involvement of a single organ, and eight had fungemia alone. Features that correlated with a poor prognosis were persistent neutropenia and disseminated visceral infection but not fungemia alone. We suggest that unusual fungi have now emerged as significant pathogens in this patient population. Fungal sinusitis, previously caused by Aspergillus species and the phycomycetes, also occurs as a result of some of these newly recognized fungi. A high level of suspicion should be maintained when any of these unusual fungi are cultured from clinical specimens from immunocompromised patients.
Melioidosis is an infection of humans and animals caused by a gram-negative motile bacillus, Pseudomonas pseudomallei. Forty-nine patients with melioidosis complicating diabetes mellitus, collagen vascular disorders, leukemia/lymphoma, and other hematologic malignancies are described. Twenty-nine of these patients had disseminated/septicemic infection, two developed toxic shock syndrome, and one with AIDS experienced recrudescent melioidosis. Patients with disseminated melioidosis often have a variety of defects in cellular immunity both in vitro and in vivo. In humans with recrudescent melioidosis, cellular immunity can be transferred by a transfer factor and by levamisole, a cellular immunopotentiating agent. The results of the treatment of our patients with disseminated/septicemic melioidosis with antimicrobial agents in combination have been successful. In recent years, four cases of fungal arteritis due to Pythium species and one case of keratitis due to Pythium were seen. Almost all patients with fungal arteritis had thalassemia; all presented with pain in the lower extremities and gangrenous lesions of the toes. Pythium species, an aquatic Phycomycetes, was identified in these cases as a human pathogen on the basis of clinical features, pathologic findings, and--of greatest importance--the isolation of the etiologic fungi. These five cases with remarkably similar presentations exhibited certain similarities with and differences from cases of mucormycosis, entomophthoromycosis, and peniciliosis.
Several fungal species, representatives of all broad groups like basidiomycetes, ascomycetes and phycomycetes, were examined for the nature of repeated DNA sequences by DNA:DNA reassociation studies using hydroxyapatite chromatography. All of the fungal species tested contained 10-20% repeated DNA sequences. There are approximately 100-110 copies of repeated DNA sequences of approximately 4 x 10(7) daltons piece size of each. Repeated DNA sequence homoduplexes showed on average 5 degrees C difference of T(e)50 (temperature at which 50% duplexes dissociate) values from the corresponding homoduplexes of unfractionated whole DNA. It is suggested that a part of repetitive sequences in fungi constitutes mitochondrial DNA and a part of it constitutes nuclear DNA.