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81.
The characterization of chitinase genes and enzymes is an important step toward global understanding of the chitinolytic system in entomopathogenic fungi. Chitinase CHIT30 from Metarhizium anisopliae var. anisopliae (strain E6) has both endo- and exochitinase activities and is a potential determinant of pathogenicity. Serum anti-CHIT30 specifically detected this chitinase amongst five isoenzymes shown in glycol-chitin activity gels. Chitinase CHIT30 secretion is upregulated by chitin, tick cuticle and low concentrations of N-acetylglucosamine (0.25%) and is downregulated by both high N-acetylglucosamine (1%) and glucose (1%) concentrations. Chitinase CHIT30 was produced at tick cuticle during fungal infection. The chi3 gene was assigned to code chitinase CHIT30 in M. anisopliae var. anisopliae.  相似文献   
82.
The spontaneous rupture with extracapsular hemorrhage of a cervical parathyroid adenoma is a rare cause of cervical and mediastinal hematoma. We describe this case to emphasize that a failure to consider this diagnosis may result in delayed operative intervention with potentially fatal complications.  相似文献   
83.
Ectopic adrenal cortical neoplasms are extremely rare, and only a few have involved the CNS. We report the first case of an intramedullary oncocytic adrenal cortical neoplasm of the spinal cord with immunohistochemical (IMHC) confirmation. A 27-year-old man presented with progressive lower extremity weakness, spastic paraparesis, decreased reflexes, and hypoesthesia below T10. A spinal myelogram showed cauda equina blockade and obliteration of sacral nerve roots. This prompted emergent surgical intervention. A well-circumscribed, approximately 3 x 2 cm, light brown to tan, intramedullary tumor was identified at the level of the conus medullaris. Histologically, the tumor showed sheets and nests of plump, cytologically bland polygonal cells with abundant eosinophilic cytoplasm. A single mitosis, but no necrosis, was identified. By IMHC, the cells were positive for inhibin, melan-A, and synaptophysin, and negative for GFAP, EMA, cytokeratins, S-100, HMB-45, and chromogranin. Electron microscopy study performed from paraffin-embedded tissues demonstrated abundant mitochondria, and lipid vacuoles. This case confirms the occurrence of adrenal cortical neoplasms in the CNS and is the first report of an intradural, intramedullary adrenal cortical adenoma of the spinal cord, and the first to occur in a male. This tumor should be considered in the differential diagnosis of tumors of the CNS.  相似文献   
84.
OBJECTIVE: To determine the histopathologic abnormalities within the cochlea in Alport syndrome. BACKGROUND: Alport syndrome, which manifests as hereditary nephritis and sensorineural hearing loss (SNHL), is caused by mutations in genes that code for the proportional, variant3, proportional, variant4, and proportional, variant5 chains of type IV collagen. The proportional, variant3, proportional, variant4, and proportional, variant5 chains of type IV collagen are present in the basement membrane of the organ of Corti. Previous temporal bone studies have failed to identify histopathologic correlates for the SNHL. METHODS: We examined temporal bones from nine individuals with a clinical diagnosis of Alport syndrome. One of our cases also had genetic testing that showed a mutation in the type IV collagen proportional, variant5 chain gene. RESULTS: By light microscopy, eight of nine cases demonstrated two unique pathologic changes: 1) a "zone of separation" between the basilar membrane and overlying cells of the organ of Corti and 2) presence of cells filling the tunnel of Corti and extracellular spaces of Nuel. The cytologic losses of hair cells, stria vascularis, and cochlear neuronal cells were insufficient to account for the observed SNHL in our cases. Electron microscopy was performed in four cases; all four demonstrated the following: 1) the zone of separation that was observed at light microscopy occurred between the basement membrane and the basilar membrane, 2) the cells within the tunnel of Corti and spaces of Nuel were morphologically similar to supporting cells, and 3) the basement membrane of strial capillaries and the spiral vessel (under the basilar membrane) were normal. CONCLUSIONS: The histopathologic correlates of cochlear involvement in Alport syndrome are abnormalities of the basement membrane of cells of the organ of Corti and dysmorphogenesis (cellular infilling of the tunnel and extracellular spaces) of the organ of Corti. We hypothesize that these abnormalities result in SNHL by altering cochlear micromechanics.  相似文献   
85.
We describe the clinicopathologic features of an Epstein-Barr virus (EBV)-associated smooth muscle tumor arising in the basal ganglia of a 10-year-old human immunodeficiency virus (HIV)-positive child. Only a few cases of intracranial smooth muscle tumors are reported in the literature and virtually all of these have been extra-axial, involving the dura or sinuses in HIV+ adults. Our case underscores the need to include an EBV-associated smooth muscle tumor in the differential diagnosis when evaluating intracranial mass lesions in immunodeficient children.Corresponding author, e-mail:  相似文献   
86.
The Socrates Intensive Programme offers annual courses focusing on the specific aspects of innovative therapeutics. The 2004 meeting was coordinated by the University of Parma and covered various subjects in the field of advanced drug delivery and pharmaceutical technology, including sessions on biopharmaceutics, pharmacokinetics, polymers, oral delivery, colloidal vectors, peptide and protein delivery, vaccines, oligonucleotide delivery, gene delivery, non-conventional routes of administration, and a graduate student symposium. The meeting had a highly interactive character and provided a unique opportunity for young scientists to present and discuss their work in an international setting.  相似文献   
87.
In the search for new antimalarial agents, nine Brazilian plant species were selected, from the Annonaceae (6), Menispermaceae (2) and Siparunaceae (1) families naturally occurring at the cerrado and Atlantic rainforest regions, in order to investigate their in vitro antiplasmodial activity. The ethanol and the alkaloid extracts were tested against K1, chloroquine-resistant, and Palo Alto, chloroquine-sensitive, strains of Plasmodium falciparum. The majority of the alkaloid extracts were more active than the ethanol ones, with IC(50) ranging 0.3-8.2 microg/mL. The crude Guatteria australis alkaloids were the most active against K1 with an IC(50) = 0.3 microg/mL. The most promising total alkaloid fractions for further bioguided isolation are those with the IC(50) < or = 5 microg/mL: G. australis, Cissampelos ovalifolia and Duguetia lanceolata.  相似文献   
88.
89.
PURPOSE: To evaluate intraocular pressure (IOP) variations after automated visual field examination in patients with primary open-angle glaucoma and in healthy subjects. PATIENTS AND METHODS: Intraocular pressure was measured in 49 patients (94 eyes) with primary open-angle glaucoma and in 13 healthy subjects (26 eyes) before and immediately after automated visual field examination. All patients had stable IOP and were using local medication to treat glaucoma. The visual field test was performed with a Humphrey 630 VF analyzer and the Central 30-2 full-threshold program. RESULTS: Mean IOP increased significantly in glaucomatous patients immediately after automated visual field examination (P < 0.01), and returned to pretest values after 1 hour (P = 0.2). Mean IOP variation was 2.38 (range, -6-11) mm Hg. In 42 (44.68%) glaucomatous eyes, IOP increased more than 2 mm Hg, with a mean increase of 5.5 mm Hg. Elderly glaucoma patients showed a significantly higher IOP rise than younger patients. No significant IOP variation was detected in healthy subjects. CONCLUSION: Intraocular pressure varied significantly and tended to increase immediately after automated visual field examination in patients with primary open-angle glaucoma. Age seemed to contribute to these IOP changes, but other factors could be involved.  相似文献   
90.
Santi M  Mena H  Wong K  Koeller K  Olsen C  Rushing EJ 《Cancer》2003,98(3):554-561
BACKGROUND: Malignant astrocytomas of the spinal cord are uncommon neoplasms with a dismal prognosis. To the authors' knowledge, little information has been published to date regarding the prognostic impact of clinicopathologic factors. METHODS: The authors studied 36 cases to investigate the prognostic effect of the World Health Organization (WHO) tumor grade, tumor localization, cell proliferative activity, p53 expression, and therapy. RESULTS: Sixteen patients (44%) underwent biopsy alone, 11 (31%) underwent subtotal resection, and 7 (19%) underwent macroscopic total excision. For two patients, there were no data available regarding surgical treatment. Among the 36 patients (mean age, 32.4 years), there were 23 males (63%) and 13 (36%) females. Their initial biopsies showed 21 (63%) glioblastoma multiforme (GBM) cases (WHO Grade 4), 13 (36%) anaplastic astrocytomas (AA) (WHO Grade 3), and 2 (6%) astrocytomas (A) (WHO Grade 2). After initial surgery, 10 (29%) patients were treated with radiation therapy alone and 7 (19%) received radiation therapy with chemotherapy. Patterns of disease recurrence included extraneural metastases (two cases), brain metastases (five cases), local extension (one case), and diffuse spread along the neuraxis (six cases). Two A (100%) and six AA (46%) cases progressed to GBM. The overall median survival time was 33 months (range, 24-42 months) for A, 10 months (range, 1-84 months) for AA, and 10 months (range, 1-43 months) for GBM. CONCLUSIONS: Patients older than 40 years have a shorter survival period compared with younger patients. There is a high risk of central nervous system dissemination in patients with this disease.  相似文献   
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