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The available world literature (since Friedman''s and Levy''s comprehensive report in 1937) regarding actinomycosis of the central nervous system is reviewed. Only cases proved by culture were included in this analysis. A total of 17 cases was collected and an additional patient with this entity is described.The important differences between actinomycosis and nocardiosis are discussed. A definite diagnosis of actinomycosis was possible only when anaerobic cultures of cerebrospinal fluid or material obtained from a brain abscess yielded colonies of typical Actinomyces organisms. The characteristic result of infection of the brain by this fungus was abscess formation, and this occurred in all except one of the cases reviewed. Penicillin appears to be the drug of choice in treatment and, where possible, surgical excision of the cerebral abscess should be undertaken. 相似文献
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Although Porphyra is commercially farmed in many countries, in South Africa only small harvests of wild populations for sale as nori have been
carried out. The discovery that Porphyra improves growth of South African abalone (Haliotis midae) farmed inland-based tanks has led to increased pressure to harvest wild populations. This paper reports on a survey of the
distribution and seasonality of Porphyra in the southern Western Cape. Porphyrawas present at all sites surveyed, and showed considerable temporal variation. A significant amount of the Porphyra present is in reserves and therefore protected from harvesting. Close rexamination of one site revealed seasonal populations
of Porphyra that occupied different niches dependent on season. Recruitment peaked in spring and autumn, leading to dense summer and
winter populations. Summer populations generally grew lower in the eulittoral than winter populations. No pattern in the mortality
of larger thalli wasde tected, though sporeling mortality was high following recruitment peaks. Although it seems that most
sites in the southern Western Cape are suitable for harvesting, the taxonomy of the genus in the region urgently needs revision
if populations are to be appropriately managed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Helen R. Please Jonathan H. Vas Nunes Rashida Patel Gerd Pluschke Mohamed Tholley Marie-Thers Ruf William Bolton Julian A. Scott Martin P. Grobusch Hkon A. Bolkan Julia M. Brown David G. Jayne 《PLoS neglected tropical diseases》2021,15(10)
BackgroundChronic wounds pose a significant healthcare burden in low- and middle-income countries. Buruli ulcer (BU), caused by Mycobacterium ulcerans infection, causes wounds with high morbidity and financial burden. Although highly endemic in West and Central Africa, the presence of BU in Sierra Leone is not well described. This study aimed to confirm or exclude BU in suspected cases of chronic wounds presenting to Masanga Hospital, Sierra Leone.MethodologyDemographics, baseline clinical data, and quality of life scores were collected from patients with wounds suspected to be BU. Wound tissue samples were acquired and transported to the Swiss Tropical and Public Health Institute, Switzerland, for analysis to detect Mycobacterium ulcerans using qPCR, microscopic smear examination, and histopathology, as per World Health Organization (WHO) recommendations.FindingsTwenty-one participants with wounds suspected to be BU were enrolled over 4-weeks (Feb-March 2019). Participants were predominantly young working males (62% male, 38% female, mean 35yrs, 90% employed in an occupation or as a student) with large, single, ulcerating wounds (mean diameter 9.4cm, 86% single wound) exclusively of the lower limbs (60% foot, 40% lower leg) present for a mean 15 months. The majority reported frequent exposure to water outdoors (76%). Self-reports of over-the-counter antibiotic use prior to presentation was high (81%), as was history of trauma (38%) and surgical interventions prior to enrolment (48%). Regarding laboratory investigation, all samples were negative for BU by microscopy, histopathology, and qPCR. Histopathology analysis revealed heavy bacterial load in many of the samples. The study had excellent participant recruitment, however follow-up proved difficult.ConclusionsBU was not confirmed as a cause of chronic ulceration in our cohort of suspected cases, as judged by laboratory analysis according to WHO standards. This does not exclude the presence of BU in the region, and the definitive cause of these treatment-resistance chronic wounds is uncertain. 相似文献
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Increasing evidence links genomic and epigenomic instability, including multiple fragile sites regions to neuropsychiatric diseases including schizophrenia and autism. Cancer is the only other disease associated with multiple fragile site regions, and genome and epigenomic instability is a characteristic of cancer. Research on cancer is far more advanced than research on neuropsychiatric disease; hence, insight into neuropsychiatric disease may be derived from cancer research results. Towards this end, this article will review the evidence linking schizophrenia and other neuropsychiatric diseases (especially autism) to genomic and epigenomic instability, and fragile sites. The results of studies on genetic, epigenetic and environmental components of schizophrenia and autism point to the importance of the folate-methionine-transulfuration metabolic hub that is diseases also perturbed in cancer. The idea that the folate-methionine-transulfuration hub is important in neuropsychiatric is exciting because this hub present novel targets for drug development, suggests some drugs used in cancer may be useful in neuropsychiatric disease, and raises the possibility that nutrition interventions may influence the severity, presentation, or dynamics of disease. 相似文献