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1.
Alexis A Gintowt Jeffrey J Germer P Shawn Mitchell Joseph D C Yao 《Journal of clinical virology》2005,34(2):155-157
BACKGROUND: The current manual sample processing method recommended for use with the TRUGENE HBV Genotyping Kit (TRUGENE HBV; Bayer HealthCare LLC, Tarrytown, NY) is labor-intensive and may be prone to specimen cross-contamination. Recent evaluations of the MagNA Pure LC (MP; Roche Applied Science, Indianapolis, IN) suggest that it is suitable for automated, contamination-free extraction and purification of viral nucleic acids from large-volume (1.0 mL) serum or plasma specimens. OBJECTIVES: We evaluated the MP Total Nucleic Acid Isolation Kit--Large Volume (Roche Applied Science) in conjunction with TRUGENE HBV to establish the analytical sensitivity (threshold titer) of the assay, in HBV DNA International Units (IU)/mL, for obtaining consistent, interpretable sequence data from TRUGENE HBV. STUDY DESIGN: HBV analytical standards, prepared as 10 replicates (1.0 mL each) at each of the following concentrations: 200, 1000, 5000, and 10,000 IU/mL, were processed by MP and analyzed by TRUGENE HBV according to manufacturer's instructions. Performance of TRUGENE HBV used in conjunction with MP sample processing was evaluated further using 22 clinical serum specimens containing low titers of HBV DNA. RESULTS: All replicates of HBV analytical standards at 1000, 5000, and 10,000 IU/mL yielded interpretable TRUGENE HBV sequences, whereas interpretable sequences were obtained in 90% (9 of 10) of the replicates at 200 IU/mL. TRUGENE HBV sequences were interpretable in 86% (19 of 22) of the clinical specimens studied. CONCLUSIONS: MP sample processing is efficient and suitable for use with TRUGENE HBV. When combined with MP sample processing, TRUGENE HBV yielded interpretable sequences from HBV analytical standards and clinical serum specimens with HBV DNA titers of > or =200 IU/mL. 相似文献
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J B Alexis R J Poppiti E Turbat-Herrera M D Smith 《The American Journal of dermatopathology》1991,13(2):189-194
A case of congenital self-healing reticulohistiocytosis in an otherwise healthy newborn boy is presented. Histological, immunohistochemical, and ultrastructural findings are described and the nosologic position of this entity is discussed. 相似文献
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Lorraine N Clark Eneli Haamer Helen Mejia-Santana Juliette Harris Suzanne Lesage Alexandra Durr Sabine Janin Bs Katja Hedrich Elan D Louis Lucien J Cote Howard Andrews Stanley Fahn Cheryl Waters Blair Ford Steven Frucht William Scott Christine Klein Alexis Brice Hanno Roomere Ruth Ottman Karen Marder 《Movement disorders》2007,22(7):932-937
Parkin mutations account for the majority of familial and sporadic early onset Parkinson's disease (EOPD) cases with a known genetic association. More than 100 mutations have been described in the Parkin gene that includes homozygous, compound heterozygous, and single heterozygous mutations. We have designed a Parkin mutation genotyping array (gene chip) that includes published Parkin sequence variants and allows their simultaneous detection. The chip was validated by screening 85 PD cases and 47 controls previously tested for Parkin mutations. Similar genotyping microarrays have been developed for other genetically heterogeneous diseases including age-related macular degeneration. Here, we show the utility of a genotyping array for Parkinson's disease by analysis of 60 subjects from the Genetic Epidemiology of Parkinson Disease (GEPD) study that includes 15 early-onset PD case probands and 45 relatives. 相似文献
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Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is frustrating for both clinicians and patients. The prostate is not scientifically proven to cause the symptoms of CP/CPPS, yet the prostate continues to be the diagnosis of convenience in this complex syndrome in men. However, if the pain is not of prostatic origin, what causes it? A heterogeneous group of insults can result in a common neurogenic pain response, resulting in recurring pain and voiding or sexual dysfunction. To add to this dilemma, certain life-threatening diagnoses, such as carcinoma-in-situ, are in the differential diagnosis and must be excluded. Urodynamics may be useful in evaluating and treating patients whose voiding symptoms predominate, such as those with concomitant overactive bladder symptoms. However, many patients with CP/CPPS will not have measurable abnormalities by conventional methods and likely suffer from a functional somatic syndrome that is best treated with a multimodality approach. 相似文献
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Miguelina Hernández Héctor Scannone Héctor J Finol Maria E Pineda Irma Fernández Alba M Vargas María E Girón Irma Aguilar Alexis Rodríguez-Acosta 《Experimental and toxicologic pathology》2007,59(2):129-137
This study explored the toxic effects of crotoxin isolated from Crotalus durissus cumanensis venom on the ultrastructure of mice cardiac autonomic nervous system. Mice were intravenously injected with saline (control group) and crotoxin diluted in saline venom (study group) at a dose of 0.107 mg/kg mouse body weight. Samples from the inter-ventricular septum were prepared for electron microscopy after 6 h (G1), 12 h (G2), 24 h (G3) and 48 h (G4). The G1 group showed some cardiomyocyte with pleomorphic mitochondria. Capillary swollen walls, nerve cholinergic endings with depleted acetylcholine vesicles in their interior and other depletions were observed. A space completely lacking in contractile elements was noticed. The G2 group demonstrated a myelinic figure, a subsarcolemic region with few myofibrils and nervous cholinergic terminal with scarce vacuoles in their interior. The G3 group demonstrated a structure with a depleted axonic terminal, mitochondrias varying in size and enhanced electron density. In addition, muscular fibers with myofibrillar structure disorganization, a depleted nervous structure surrounded by a Schwann cell along with an abundance of natriuretic peptides, were seen. An amyelinic terminal with depleted Schwann cell and with scarce vesicles was also observed. Finally, axonic lysis with autophagic vacuoles in their interior and condensed mitochondria was observed in the G4 group. This work describes the first report of ultrastructural damage caused by crotoxin on mice cardiac autonomic nervous system. 相似文献
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Dendritic cells (DCs) constitute the link between innate and adaptive immunity by directly recognizing pathogen-associated molecular patterns (PAMPs) on bacteria and by processing and presenting bacterial antigens to T cells. Recognition of PAMPs renders DCs as professional antigen-presenting cells with the ability to prime naive T cells and to initiate the adaptive immune response against pathogen-derived antigens. For this reason, any interference with DC function might be advantageous for bacterial survival and dissemination. Identification of the molecular interactions occurring between DCs and bacterial pathogens is necessary to understand the mechanisms that virulent bacteria have evolved to prevent recognition by the adaptive immune system. This could be helpful in the identification of possible new targets that might lead to the design of effective therapies aimed at preventing or treating serious infections by these pathogens. In this article, we focus on Salmonella enterica serovar Typhimurium, the causative agent of typhoid-like disease in the mouse, and how it is able to escape from DC-mediated antigen presentation by avoiding lysosomal degradation. This feature of virulent Salmonella requires the functional expression of the Type Three Secretion System (TTSS) and effector proteins encoded within the Salmonella pathogenicity island 2 (SPI-2). Recent studies have demonstrated that impairment of DC function by the activity of SPI-2 gene products is crucial for Salmonella pathogenesis. 相似文献
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1. Pressures have been measured in the thoracic duct of anaesthetized and conscious dogs to ascertain the mean pressures, the nature of the pressure waves and the pressure gradients along the duct and between it and the great veins.2. The average mean pressure in the thoracic duct of ten anaesthetized dogs was 1.4 mm Hg. The pressure waves were secondary to respiration and the pulsations of the aorta. No waves were transmitted from the great veins.3. Pressures in conscious dogs varied from day to day, sometimes being positive, sometimes negative. They were increased by panting and by drinking.4. The pressure gradients along the duct were small, no more than 0.5-2.0 mm Hg along its whole length.5. No evidence was found of spontaneous contractions of the duct. 相似文献