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11.
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   
12.
Canine visceral leishmaniasis (CVL) is a zoonosis and a chronic systemic disease of the dog caused by a protozoan by the species Leishmania infantum in the Old World and Leishmania chagasi in the New World. Several methods are currently employed for the diagnosis of CVL including microscopic detection of the parasite in bone marrow and lymph node aspirates, demonstration of specific antibodies anti-Leishmania in sera from infected animals, and isolation of the parasite by in vitro culture or by inoculation of laboratory animals. However, a definitive diagnosis is based on the actual detection of the parasite, which is conventionally achieved by examining Giemsa-stained smears or histopathological sections stained with hematoxylin and eosin. These methods have a low sensitivity, and therefore, they are often inconclusive. This is particularly true in canine organs that have a low level of parasitism such as kidneys, lungs, central nervous system, and testis, or, in some cases, the skin. The technique for immunohistochemical detection of leishmanial amastigotes in canine tissues has been reported previously and has proved to be undoubtedly efficient for the diagnosis. In this paper, we describe a straightforward and inexpensive immunohistochemical approach for Leishmania detection in formalin-fixed paraffin-embedded canine tissues. Amastigote forms of Leishmania were easily observed within macrophages in several organs from naturally infected dogs using the streptavidin-biotin immunohistochemical method with canine hyperimmune serum as the primary antibody. In addition, the secondary antibody used was not specific to canine immunoglobulin, characterizing a cross-immune reaction. Our results indicate that this technique could be a useful tool for epidemiological, clinical, and histopathological studies.  相似文献   
13.
OBJECTIVES/HYPOTHESIS: Cyclin D1, a cell cycle regulator localized to chromosome 11q13, is amplified in several human tumors including head and neck squamous cell carcinoma (HNSCC). Amplification and/or overexpression of cyclin D1 have been correlated to a poor prognosis. Deletion of the p16 gene, localized to 9p21, has also been observed in a significant proportion of HNSCC. The p16 gene regulates cyclin D1-CDK4 activity and prevents retinoblastoma tumor suppressor gene phosphorylation, thereby downregulating cellular proliferation. Detection of cyclin D1 amplification and p16 deletion using a simple and sensitive method will be valuable for the development of effective treatment modalities for head and neck cancer. STUDY DESIGN: We have used fluorescence in situ hybridization (FISH) to study cyclin D1 amplification and p16 gene deletion in head and neck tumors. Both single- and dual-color FISH were performed. METHODS: Paraffin-embedded tissues from 103 patients with HNSCC were analyzed using genomic DNA probes for cyclin D1 and p16. Dual-color FISH was performed with chromosome 11 or 9 centromeric probes as a control. Twenty-eight of these samples were analyzed for p16 expression by immunohistochemistry. RESULTS: Cyclin D1 amplification was observed in 30% (31/103) of patients, and p16 deletion in 52% (54/103). Lack of p16 expression was observed in 64% (18/28) of patients. There was a good correlation between the deletion of p16 sequences and the loss of p16 expression (P = .008). Amplification of cyclin D1 had a statistically significant association with recurrence, distant metastasis, and survival at 36 months. There was a significant association between p16 deletion and the development of distant metastases. Cyclin D1 amplification and p16 deletion together correlated with recurrence, distant metastasis, and survival. CONCLUSIONS: We demonstrate that FISH is a simple and sensitive method for detecting cyclin D1 amplification and p16 deletion in head and neck cancer. Our results suggest that these two genetic aberrations together portend a poorer outcome than either of the abnormalities alone in head and neck cancer.  相似文献   
14.
There is only scant information on sleep characteristics and long-term follow-up in patients with Kleine-Levin syndrome (KLS). This study describes the clinical course, results of polysomnography and long-term follow-up in a relatively large group of patients with KLS. During the years 1982-97, we encountered 34 patients (26 males and eight females) with KLS. We were able to obtain the original polysomnographs from 28 males and four females. In 25 patients, data regarding their present state of health were obtained. Fourteen agreed to be present at a detailed interview and examination while 11 gave the information by phone. The mean age at onset was 15.8 +/- 2.8 years and the mean diagnostic delay, 3.8 +/- 4.2 years. The mean duration of a single hypersomnolent attack was 11.5 +/- 6.6 days. The main abnormal findings extracted out of 35 polysomnographs obtained from 32 patients during and/or in-between attacks included: decreased sleep efficiency, and frequent awakenings from sleep stage 2. All 25 patients reported present perfect health, with no evidence of behavioral or endocrine dysfunction. In adolescents with periodic hypersomnia, the diagnosis of KLS should be explored. Sleep recordings during a hypersomnolent period will often show frequent awakenings from sleep stage 2. The long-term prognosis is excellent.  相似文献   
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16.
Objectives/Hypothesis A comprehensive review of the literature of clival metastases and presentation of two additional cases.Study Design Literature review and report of two cases.Methods A literature review of the MEDLINE database (1950 to January 19, 2013) was performed to identify all cases of patients with metastatic disease to the clivus. Additionally, two novel cases are presented.Results In total, 47 cases were identified in the literature, including the two cases presented in this study. Metastatic disease to the clivus is the initial presenting symptom of the primary malignancy in 36% (13/36) of the cases. When there was a history of malignancy, the median interval of time to clival metastases was 24 months (range 1 to 172 months). Clinical symptoms manifested often as cranial neuropathies, with at least abducens palsies as the initial presenting symptom in 61.9% (26/42) of patients. Tumor pathology was diverse, but several pathologies were seen more commonly: prostate carcinoma (18.1%, 9/47), hepatocellular carcinoma (10.6%, 5/47), and thyroid follicular carcinoma (8.5%, 4/47).Conclusion Although clival metastases are extremely rare, they are an important part of the differential of clival masses as they can be the presenting symptom of distant malignancy.Level of Evidence 4.  相似文献   
17.
Thirty cases of histoplasmosis observed at the University Hospital of the Federal University of Mato Grosso do Sul (HU-UFMS) from January 1998 to December 2005 are reported. Most (83.3%) of the patients were men, average 33.4 years old, 63.3% of them were born and living in Mato Grosso do Sul and 83.3% presented AIDS as an underlying disease. In almost all cases (96.7%) the disease occurred in its disseminated form and the most frequent clinical manifestations were: fever (83.3%), weight loss (70.0%), cough (63.3%), hepatomegaly and splenomegaly (40.0%), and lymph node enlargement (36.7%). The laboratory diagnosis was obtained in 29 patients by isolation of Histoplasma capsulatum from various clinical specimens cultivated in Sabouraud dextrose and brain heart infusion agar and in 16 patients the fungus was observed by direct microscopy of Giemsa-stained smears. The observed mortality was 40%. This is the first report in the literature of the occurrence of histoplasmosis in Mato Grosso do Sul State.  相似文献   
18.
ObjectiveDetermine the relation of xanthine oxidase (XO) activity and the outcome of septic patients and its relation to oxidative damage and clinical parameters of sepsis severity.Design and methodsPatients admitted over a 6-month period were enrolled. Patients were assigned to groups according to the diagnosis of sepsis (n = 8), severe sepsis (n = 28) or septic shock (n = 36). Blood samples were collected to the determination of thiobarbituric acid reactive species (TBARS), protein carbonyls and XO activity.ResultsNone of the studied oxidative parameters determined at the time of diagnosis were related to sepsis severity. XO activity, but not oxidative damage parameters, at the time of sepsis diagnosis was significantly higher in non-survival septic patients. In contrast, 24 h after sepsis diagnosis, XO activity was lower in non-survivors septic patients.ConclusionsXO activity was increased in non-survivors patients and the variations in XO activity could be used for outcome prediction.  相似文献   
19.
Several compounds of great pharmacological interest contain the triazole and imidazole rings. In order to find new drugs with antileishmanial activity we have synthesized and evaluated new imidazole and triazole compounds carrying either the carbaldehyde or the difluoromethylene functionalities against promastigote forms of Leishmania amazonensis. Among the compounds tested difluoromethylene azoles 4b and 8f have inhibited the parasite growth significantly. Our results show that the introduction of the difluoromethylene moieties has turned the inactive carbaldehydes into active antileishmanial compounds.  相似文献   
20.
The purpose of this randomized, prospective trial was to determine if Bachmann's bundle pacing reduces the incidence of AF after CABG. The study included 161 patients with no history of AF who were randomized to three groups. Group 1 included 50 patients as controls. Group 2 included 60 patients who had an epicardial wire placed at the lateral wall of the right atrium. In the 51 patients of group 3, the wire was placed at the Bachmann's bundle. In groups 2 and 3, atrial pacing (AAI 96 beats/min) was initiated immediately after CABG and continued for 5 days. The study endpoint was AF lasting > or = 1 minute. Baseline clinical parameters were similar in all three groups. The incidence of AF was not reduced by pacing (group 1: 42%; group 2:48%; group 3:37%; P = NS). The paced P wave duration was increased in group 2 (129 +/- 14 ms vs group 3: 96 +/- 21 ms; P < 0.05). Paced P wave duration was a risk factor for postoperative AF (odds ratio 1.015; 95% CI 1.0021-1.028; P < 0.05). Analysis comparing the pacing groups revealed a reduction in AF during Bachmann's bundle pacing (50 vs 29%; P < 0.01). Pacing thresholds were significantly better at Bachmann's bundle compared to group 2. In conclusion, an anatomically guided pacing at the Bachmann's bundle does not reduce the overall incidence of postoperative AF compared to controls. However, the Bachmann's bundle offers favorable capabilities for postoperative a trial pacing, and thus it is a preferable site for electrode placement if postoperative atrial pacing is required.  相似文献   
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