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91.
There has been much debate about the use of the so-called "vaccinate-to-live" policy for the control of foot-and-mouth disease (FMD) in Europe, according to which, spread of the FMD virus (FMDV) from future outbreaks could be controlled by a short period of "emergency" vaccination of surrounding herds, reducing the need for large-scale preemptive culling of at-risk animals. Since vaccinated animals may become subclinically infected with FMDV following challenge exposure, it is necessary to either remove all vaccinates (vaccinate-to-kill) or to detect and remove vaccinates in which virus is circulating or has established persistent infections (vaccinate-to-live), in order to rapidly regain the most favoured trading status of FMD-free without vaccination. The latter approach can be supported by testing vaccinated animals for the presence of antibodies to certain non-structural proteins (NSP) of FMDV, which are induced by infection with the virus, but not by vaccination with purified FMD vaccines. Using test sensitivity and specificity data established at a recent workshop on NSP assays [Brocchi E, Bergmann I, Dekker A, Paton DJ, Sammin DJ, Greiner M, et al. Comparative performance of six ELISAs for antibodies to the non-structural proteins of foot-and-mouth disease. Vaccine, in press], this paper examines the ways in which serological testing with NSP ELISAs can be used and interpreted and the effect that this will have on the confidence with which freedom from infection can be demonstrated within guidelines specified by the World Animal Health Organisation and the European Commission.  相似文献   
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Microcystins are a family of potent hepatotoxins and liver tumor promoters produced by several genera of cyanobacteria including Microcystis, Nodularia, Anabena, Nostoc, etc. They are chemically very stable and represent a public health threat when they occur in water used for human consumption. We investigated the DNA damage effects of M. aeruginosa UTEX 2385 in mouse liver in vivo and also in mammalian cells in vitro. The DNA damage effect is compared with purified toxin microcystin-LR (MCLR) in non-hepatic cells viz. baby hamster kidney cells (BHK-21) and mouse embryo fibroblasts primary cells (MEF). Cell-free extracts of UTEX 2385 induced significant DNA fragmentation at 0.5, 1 and 2 LD(50) (32.7, 65.4 and 130.8 mg/kg, respectively) and it was also time dependent. M. aeruginosa UTEX 2385 and MCLR induced significant DNA fragmentation in BHK-21 and MEF cells at 100 and 1.0 μg/ml concentration. Electrophoretic analysis revealed necrotic DNA damage by UTEX 2385 in vivo. Both the toxins caused smear in agarose gel electrophoresis indicating the necrotic DNA damage in MEF cells, whereas, multiple DNA fragments in BHK-21 cells. The DNA damage effect of the toxin is supported by data on hepatotoxicity in vivo and cytotoxicity in vitro.  相似文献   
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The development of a one-step SYBR Green I-based real-time RT-PCR assay is reported for detection and quantification of Chikungunya virus (CHIKV) in acute-phase patient serum samples by targeting the E1 structural gene. A linear relationship was obtained between the virus concentration and cycle threshold (C(t)) value over a range of 10(7)-0.1PFU/ml. The reported assay was found to be 10-fold more sensitive compared to conventional RT-PCR with a detection limit of 0.1PFU/ml. The feasibility of this reported assay system for clinical diagnosis was validated with 51 suspected acute-phase serum samples of the recent CHIKV epidemic in southern India, 2006. The comparative evaluation with acute-phase patient serum samples revealed the higher sensitivity of real-time RT-PCR assay by picking up six additional samples with low copy number of template. None of the healthy serum samples analyzed in this study showed amplification. The quantification of the viral load in the acute-phase serum samples was also determined employing the standard curve, which varies from 0.1 to 10(7)PFU/ml. These findings demonstrated that the reported assay has the potential usefulness for clinical diagnosis due to simultaneous detection and quantification of Chikungunya virus in acute-phase patient serum samples.  相似文献   
95.
Tumor necrosis factor--alpha (TNF), one of the mediators of septic shock, has a role in the immunopathological complications of several infections. However, its role in leprosy is yet unclear. In this study, serum TNF and IL-1 levels in 64 patients spread over the spectrum of leprosy [lepromatous leprosy (LL), 30; borderline lepromatous, 12; borderline borderline, 8; and borderline tuberculoid-tuberculoid leprosy, 14] were measured at the time of admission. Elevated levels of TNF ranging from 15 to 4500 pg/ml were detected in lepromatous leprosy cases (399 +/- 189) and low levels ranging from 15 to 160 pg/ml were detected in the tuberculoid form of leprosy. Patients undergoing type 1 and type 2 lepra reactions also exhibited high TNF levels of 15-2100 pg/ml. Of the 14 clinically healthy individuals studied, 3 showed TNF levels of 15, 50, and 58 pg/ml. Interleukin 1-beta (IL-1) levels were found to be significantly higher in LL cases (70-5000 pg/ml) (328 +/- 184) in comparison to other groups or normal controls (9 +/- 3). The coefficient of correlation between TNF and IL-1 levels was statistically significant in LL and reaction cases (r = 0.96, P less than 0.001). These patients were followed up as outpatients for a period of 1 year. It was observed that 4 out of 8 patients with TNF levels greater than 100 pg/ml went into lepra reactions between 2 and 6 months after entry into the study, whereas only 5 out of 56 with less than 100 pg/ml went into mild lepra reactions (chi 2 = 9.7, P less than 0.01). Determination of TNF and IL-1 levels thus seems to have a prognostic significance in terms of lepra reaction in patients.  相似文献   
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We present the largest single series of cases (n = 5) of penoscrotal transposition (PST) with carefully documented nongenitourinary/anal anomalies, none of which fell into categories of known syndromes, associations, sequences or chromosome disorders. Several unexpected anomalies were observed including coloboma of the iris and retina, hydrocephalus, microcephaly, diaphragmatic hernia, tracheo-esophageal fistula/esophageal atresia and cleft palate. The most frequent anomalies other than PST were renal defects (100%) such as renal agenesis and dysplasia, imperforate anus (60%), central nervous system anomalies (60%) and preaxial upper limb defects (40%). Cardiovascular defects (atrial septal defect, double aortic arch with vascular ring) were noted in only one case. The surviving patients (3/5) had postnatal growth failure and mental retardation. Our 5 PST patients are compared to 16 well-documented cases from the literature. The overall incidence of various extragenital abnormalities were: renal (90%), mental retarardation (60%), imperforate anus (33%), central nervous system (CNS) anomalies (29%), vertebral defects (29%), preaxial limb defects (24%) and congenital heart disease (19%). PST is a rare heterogenous anomaly, the detection of which should warrant careful clinical evaluation to rule out other anomalies, especially of the urinary system, gastrointestinal tract, upper limbs, craniofacial region and central nervous system. PST may be a localized field defect involving the genitourinary system; however, the wide variety of more distant defects noted in our series and the literature would raise doubt about that assumption. The high frequency of growth deficiency and mental retardation has also not been given due respect as accompanying problems associated with PST. © 1995 Wiley-Liss, Inc.  相似文献   
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建立了顶空毛细管GC法测定盐酸伪麻黄碱中的苯、甲苯、乙苯、对二甲苯、间二甲苯和邻二甲苯等6种有机溶剂的残留晕。采用程序升温,甲醇为溶剂,各有机溶剂的平均同收率分别为101.5%、104.5%、101.4%、98.0%、99.4%和100.1%,RSD为6.1%、7.0%、5.3%、6.5%、4.8%和5.2%。  相似文献   
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