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21.
Rapid detection and quantitation of hepatitis B virus DNA by real-time PCR using a new fluorescent (FRET) detection system. 总被引:6,自引:0,他引:6
Sani Hussein Aliyu Muktar Hassan Aliyu Hamisu M Salihu Surendra Parmar Hamid Jalal Martin David Curran 《Journal of clinical virology》2004,30(2):191-195
BACKGROUND: The diagnosis of hepatitis B virus (HBV) has until recently been based on traditional serologic methods targeting viral antigens and antibodies to viral proteins. The development of molecular methods allowing for the quantitation of HBV DNA is proving clinically valuable for monitoring therapy and detecting early treatment failures. OBJECTIVES: Here we report a new real-time (LightCycler) quantitative PCR for the detection of HBV DNA based on sequence specific hybridisation probes (designed in-house), targeting the HBV surface antigen. STUDY DESIGN: The assay was evaluated using a 10-fold dilution series of standard HBV DNA [Eurohep standard reference 1, genotype A, HBsAg subtype adw with a unitage of 10(6) WHO. i.u./ml] and 89 clinical serum samples. The performance was measured against a quantified standard HBV DNA working reagent (NIBSC code 98/780) and the sensitivity compared with our conventional thermal-block PCR. RESULTS AND CONCLUSION: Real-time PCR detected HBV DNA in 45% (40/89) and thermal-block PCR in 16% (14/75) of clinical samples. Results for 26 samples were below the detection limit of the thermal-block PCR but could be quantified by real-time (LightCycler) PCR. The LightCycler assay was at least 5 logs more sensitive than thermal-block PCR and could detect HBV in a linear range between 5 and 10(7) i.u. per reaction. The broad generic nature of the PCR primers coupled with the enhanced sensitivity and specificity of the fluorescent hybridisation probes makes this assay potentially valuable for both routine diagnostic and epidemiological work. 相似文献
22.
The mesiobasal limbic system is of particular significance in the surgical treatment of temporo-medial tumors and epilepsy. It consists of the uncus, amygdaloid body, hippocampus, dentate gyrus, subiculum, fasciolar gyrus and the parahippocampal gyrus. Knowledge of the vascular microanatomy is a key to the surgical treatment of pathologies in the region. The anterior choroidal artery was selectively injected in fresh brain specimens 50 specimens with a gelatinous ink mixture to demonstrate vascular territories in stereotactic brain slices, and 50 with a Biodur resin to obtain casts for microanatomical evaluation. The cast technique was also applied to 35 specimens injected into the posterior cerebral artery. The rostral third of the temporomedial region is mainly supplied by branches of the anterior choroidal artery. The occipital two thirds are supplied by hippocampal branches, the posteromedial choroidal artery and the inferior temporal branches of the posterior cerebral artery. Important vessel variations with significant implications for the preoperative Wada-test are presented 相似文献
23.
Hussein MR Hassan HI Hofny ER Elkholy M Fatehy NA Abd Elmoniem AE Ezz El-Din AM Afifi OA Rashed HG 《Journal of clinical pathology》2005,58(2):178-184
BACKGROUND: Systemic sclerosis (SSc) is a multisystem disease with underlying immune mechanisms. AIMS: To investigate the clinicopathological characteristics of the lesions; immunological alterations in the bronchoalveolar lavage fluid (BALF), peripheral blood, and skin; and correlations between the clinicopathological characteristics and immunological alterations in SSc. MATERIALS/METHODS: Skin biopsies, BALF, and peripheral blood samples were obtained from 19 patients (18 women, one man) with SSc and six age and sex matched healthy controls (HCs). Mononuclear inflammatory cells (MICs), CD4/CD8 cells, tumour necrosis factor alpha (TNFalpha), and interleukin 1beta (IL1-1beta) concentrations were examined in all samples using histological methods, enzyme linked immunosorbent assay, and immunoperoxidase staining. RESULTS: The mean (SD) age of the patients with SSc was 34.8 (2.6) years. Proteinuria, positive rheumatoid factor, and C reactive protein were seen in 15.8%, 26.3%, and 26.3% of patients, respectively. Compared with HCs, there were significantly higher: total MICs (macrophages, lymphocytes), neutrophils, and eosinophils in BALF, blood, and skin (all p<0.05); cytokine concentrations in BALF (TNFalpha, p<0.001; IL-1, p<0.01) and peripheral blood (p<0.01 and p<0.05); and CD8/CD4+ T cells in peripheral blood (p<0.05). Compared with HCs, lesional skin had significantly higher histiocyte cell counts (p<0.05), lower lymphocyte counts (p<0.05), and higher CD4/CD8 ratios (p<0.001). There were significant correlations between cytokine concentrations and CD8+ T cells and forced vital capacity (p<0.001 and p<0.01, respectively). CONCLUSIONS: MICs, CD4/CD8+ cells, and cytokines are altered in SSc. These alterations correlated with the underlying disease process and therefore may have pathogenic, modulatory, and potential prognostic roles in SSc. 相似文献
24.
Apoptosis in the ovary: molecular mechanisms 总被引:19,自引:0,他引:19
Hussein MR 《Human reproduction update》2005,11(2):162-177
Cell death was first described in rabbit ovaries (Graaffian follicles), the phenomenon being called 'chromatolysis' rather than apoptosis. In humans, the ovarian endowment of primordial follicles is established during fetal life. Apoptotic cell death depletes this endowment by at least two-thirds before birth, executed with the help of several players and pathways conserved from worms to humans. To date, apoptosis has been reported to be involved in oogenesis, folliculogenesis, oocyte loss/selection and atresia. Several pro-survival and pro-apoptotic molecules are involved in ovarian apoptosis with the delicate balance between them being the determinant for the final destiny of the follicular cells. This review critically analyses the current knowledge about the biological roles of these molecules and their relevance to the dynamics of follicle development. It also presents the existing literature and assesses the gaps in our knowledge. 相似文献
25.
Zusammenfassung Es wird über einen Fall akuter Erythroleukämie mit G-Trisomie berichtet und die mögliche Bedeutung hereditärer Faktoren für die Manifestation akuter Leukämien diskutiert.
Summary The cytogenetic analyses of direct bone marrow preparations in a 53 years old male with acute erythroleukaemia of 9 months disease history, revealed persistently a G-trisomy in a dominant cell line with 47 chromosomes. The peripheral blood culture preparations with phytohaemagglutinin exhibited normal diploid cell line.The frequent occurrence of akute leukaemia in Down's syndrome tempts to implicate that leukaemia with G-Trisomy having no signs of Down's syndrome is a somatic mutation initiated by some unknown hereditary recessive genes mechanisms.相似文献
26.
Wang D Alpard SK Savage C Yamani HN Deyo DJ Nemser S Zwischenberger JB 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2003,49(6):673-677
A new perfluorocopolymer coating for micropore hollow fiber gas exchangers was developed to improve gas exchange, reduce plasma leakage, and reduce blood-surface interactions. The present authors evaluated gas exchanger performance using this new coating in a prospective, randomized, controlled, unblinded, large animal model of CO2 retention. Adult sheep (30-40 kg), under general anesthesia, underwent cannulation of the carotid artery (12 F) and jugular vein (14 F). The perfluorocopolymer coated (n = 5) and uncoated (n = 5) gas exchangers were attached to an arteriovenous CO2 removal (AVCO2R) circuit. Blood gases, CO2 removal, and hemodynamics were monitored throughout the 6 hour study. Average CO2 removal was 107.6 +/- 15.6 ml/min (coated) vs. 93.0 +/- 13.9 ml/min (uncoated; p < 0.01). PaCO2 and CO2 removal for both coated and uncoated did not deteriorate significantly over the study. Average AVCO2R blood flow was 1,130 +/- 25 ml/min (coated) versus 1,101 +/- 79 ml/min (uncoated; p = not significant). Likewise, cardiac output and AVCO2R blood flow did not change over the duration of the study. No significant differences in the pressure gradient or resistance between devices (coated, 6.89 +/- 1.14 mm Hg/L/min; uncoated, 6.42 +/- 0.23 mm Hg/L/min) was noted. The authors concluded that the new perfluorocopolymer coated gas exchanger improved CO2 removal without compromising hemodynamics in an acute performance evaluation. 相似文献
27.
Ellen M H Mitchell Olusola Adedeji Adejumo Hussein Abdur-Razzaq Chidubem Ogbudebe Nkem Chukwueme Samson Bamidele Olorunju Mustapha Gidado 《JMIR Public Health and Surveillance》2021,7(3)
BackgroundThe greatest risk of infectious disease undernotification occurs in settings with limited capacity to detect it reliably. World Health Organization guidance on the measurement of misreporting is paradoxical, requiring robust, independent systems to assess surveillance rigor. Methods are needed to estimate undernotification in settings with incomplete, flawed, or weak surveillance systems. This study attempted to design a tuberculosis (TB) inventory study that balanced rigor with feasibility for high-need settings.ObjectiveThis study aims to design a hybrid TB inventory study for contexts without World Health Organization preconditions. We estimated the proportion of TB cases that were not reported to the Ministry of Health in 2015. The study sought to describe TB surveillance coverage and quality at different levels of TB care provision. Finally, we aimed to identify structural-, facility-, and provider-level barriers to notification and reasons for underreporting, nonreporting, and overreporting.MethodsRetrospective partial digitalization of paper-based surveillance and facility records preceded deterministic and probabilistic record linkage; a hybrid of health facilities and laboratory census with a stratified sampling of HFs with no capacity to notify leveraged a priori knowledge. Distinct extrapolation methods were applied to the sampled health facilities to estimate bacteriologically confirmed versus clinical TB. In-depth interviews and focus groups were used to identify causal factors responsible for undernotification and test the acceptability of remedies.ResultsThe hybrid approach proved viable and instructive. High-specificity verification of paper-based records in the field was efficient and had minimal errors. Limiting extrapolation to clinical cases improved precision. Probabilistic record linkage is computationally intensive, and the choice of software influences estimates. Record absence, decay, and overestimation of the private sector TB treatment behavior threaten validity, meriting mitigation. Data management demands were underestimated. Treatment success was modest in all sectors (R=37.9%–72.0%) and did not align with treatment success reported by the state (6665/8770, 75.99%). One-fifth of TB providers (36/178, 20%) were doubtful that the low volume of patients with TB treated in their facility merited mastery of the extensive TB notification forms and procedures.ConclusionsSubnational inventory studies can be rigorous, relevant, and efficient in countries that need them even in the absence of World Health Organization preconditions, if precautions are taken. The use of triangulation techniques, with minimal recourse to sampling and extrapolation, and the privileging of practical information needs of local decision makers yield reasonable misreporting estimates and viable policy recommendations. 相似文献
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30.
Laparoscopic Assisted Cystectomy and Lymphadenectomy for Bladder Cancer: Initial Experience 总被引:17,自引:0,他引:17
This study discusses our initial experience in the field of laparoscopic management of bladder carcinoma. Ten patients with
invasive bladder tumors of variable histology and ranging from stage T2 to T3b were submitted to this procedure. Intraoperative
assessment, lateral dissection, posterior dissection, anterior dissection, and urethral transection were achieved laparoscopically.
The specimen retrieval and continent pouch construction was performed through a limited abdominal incision. This new regimen
allows precise radical lymphadenectomy, early postoperative mobility, fewer wound complications, and shorter hospital stay.
The early postoperative results of this procedure are encouraging. Modification and continuous refinement of the technique
is still ongoing. 相似文献