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81.
Systemic distribution of woodchuck hepatitis virus in the tissues of experimentally infected woodchucks 总被引:6,自引:0,他引:6
To better assess the extent of the tissue tropism of mammalian hepadnaviruses, 10 tissues from each of six woodchucks were examined for the presence and state of woodchuck hepatitis virus (WHV) nucleic acids 15 months after experimental WHV infection. The tissues examined were peripheral blood lymphocytes, lymph node, spleen, bone marrow, thymus, pancreas, kidney, ovary, testis, and liver. Tissue samples from three chronically infected animals and three animals with serologic patterns of recovery (serum: WHsAg-, anti-WHs+, anti-WHs+, WHV DNA-) from acute WHV infection were analyzed in parallel by in situ hybridization and Southern and Northern blot techniques. WHV nucleic acids were detected in several individual tissues from each animal examined, although not all tissues in every animal contained WHV. Substantial differences were observed among the various tissues and animals with respect to the frequency, level, and intratissue distribution of WHV nucleic acids, as well as the presence of different viral genomic forms. Active WHV DNA replication was present only in the liver and spleen of the chronically infected animals. No evidence of ongoing WHV DNA replication was found in any of the tissues from the recovered animals. WHV DNA was homogeneously distributed among all hepatocytes in the livers of the chronic carriers. By contrast, WHV DNA in all the extrahepatic tissues, and in the livers of the recovered animals, was detected only in scattered foci of cells. 相似文献
82.
Methylation of human T-cell leukemia virus proviral DNA and viral RNA expression in short- and long-term cultures of infected cells 总被引:9,自引:0,他引:9
Leukemic peripheral blood lymphocytes from individuals infected with the human T-cell leukemia/lymphoma virus (HTLV) were found to express little or no viral RNA before being put into tissue culture. Within 24-48 hr, viral RNA expression increased at least four- to eightfold. Established HTLV-infected cell lines constitutively express viral RNA. Southern blots of DNA from HTLV-infected cells digested with the methylation-sensitive restriction enzyme HpaII showed that the proviral DNA was methylated in all of the uncultured peripheral blood cells tested. In contrast, no proviral methylation was detected in any of the cell lines examined, suggesting a functional correlation between methylation and viral RNA expression. However, DNA from HTLV-infected lymphocytes cultured for 48 hr (by which time increases in viral RNA expression are evident) did not differ detectably with respect to proviral DNA methylation from uncultured cells, suggesting that the increase in viral RNA expression after short-term culture is mediated by mechanisms independent of changes in DNA methylation. 相似文献
83.
84.
An anti-actin monoclonal antibody inhibits the zona pellucida-induced acrosome reaction and hyperactivated motility of human sperm. 总被引:6,自引:0,他引:6
D Y Liu M Martic G N Clarke I Grkovic C Garrett M E Dunlop H W G Baker 《Molecular human reproduction》2002,8(1):37-47
We report an inhibitory effect of an anti-actin monoclonal antibody (mAb) on the human zona pellucida (ZP)-induced acrosome reaction (AR). Motile sperm were incubated with native human ZP for 2 h in medium containing either the anti-actin mAb, an irrelevant control mAb or cytochalasins B or D (40 micromol/l). Sperm bound to the ZP were recovered and the AR was determined by fluorescein-labelled Pisum Sativum agglutinin. Anti-mouse immunoglobulin G (mIgG) Dynabeads, immunofluorescence and immunogold were used to detect the location of the anti-actin mAb in sperm. The anti-actin mAb significantly inhibited the ZP-induced AR (equivalent to cytochalasins), the ionophore A23187-induced AR and hyperactivation of sperm in medium. After incubation with anti-actin mAb, anti-mIgG beads bound to the head of >50% of sperm recovered after binding to the ZP and 10% of sperm remaining in the medium. The proportion of sperm that bound anti-mIgG beads after recovery from binding to the ZP in the presence of the anti-actin mAb was significantly correlated with the ZP-induced AR in the absence of the antibody. Immunofluorescence and immunogold demonstrated entry of the anti-actin mAb into sperm. This study suggests that the sperm plasma membrane becomes permeable to the anti-actin mAb during capacitation and initiation of the AR. 相似文献
85.
Laura McGillis Nimish Mittal Daniel Santa Mina Joyce So Medha Soowamber Aliza Weinrib Leslie Soever Dmitry Rozenberg Louis Liu Yvonne Tse Joel Katz George S Charames Kieran Murphy Peter Vadas Maxwell P Slepian Scott Walsh Lindsay Wilson Arnon Adler Alyssa Franzese Laura Hussey Dayna‐Lynn Nevay Juan Guzman Hance Clarke 《American journal of medical genetics. Part A》2020,182(3):484-492
The new 2017 diagnostic criteria for hypermobile Ehlers–Danlos Syndrome (hEDS) provide a framework for diagnosing hEDS but are more stringent than the previous Villefranche criteria. Our clinical experience at the GoodHope EDS clinic was that the 2017 criteria left many highly symptomatic patients without a diagnosis of hEDS. We conducted a retrospective cohort study to confirm our clinic experience and assess the accuracy of the 2017 diagnostic criteria for hEDS in patients who had a previous hEDS diagnosis based on the Villefranche criteria. Our study found that 15% (n = 20 of 131) of patients with a prior diagnosis of hEDS met the 2017 diagnostic criteria, and many of the traits used to distinguish hEDS were not significantly more frequent in patients who met 2017 criteria versus those who did not. In both groups objective systemic manifestations were found less frequently than subjective systemic manifestations. Beighton score (BS) as assessed by primary care practitioner was found to be higher than assessment by EDS practitioner in 81% (n = 74 of 91) of cases. Generalized joint hypermobility was confirmed in only 46% (n = 51 of 111) of patients who had a previous diagnosis of hEDS. Higher BS did not correlate with increased number of systemic manifestations in our cohort. Common comorbidities of hEDS were found with similar frequency in those who met 2017 criteria and those who did not. Based on our cohort, the 2017 hEDS diagnostic criteria require refinement to improve its diagnostic accuracy. 相似文献
86.
Care of diabetic patients in hospital clinics and general practice clinics: a study in Dudley. 下载免费PDF全文
A five year retrospective casenote review was undertaken of 452 patients attending 11 different general practice diabetic clinics, and 506 patients attending a diabetic clinic at hospital A and 210 patients attending a diabetic clinic at hospital B. The populations attending the clinics, the degree of glycaemic control achieved and the monitoring for the development of diabetic complications were investigated. Insulin dependent patients comprised 57.9% of patients attending the diabetic clinic at hospital A, 35.7% at hospital B and 25.0% of patients attending the diabetic clinics at general practices. Of these 55.6%, 37.3% and 30.1% respectively received multiple daily insulin injections. Hospital A had a higher proportion of patients under 40 years old than hospital B or the general practice clinics. The ages of diabetic patients attending the general practice diabetic clinics were broadly similar to those attending hospital B. Significantly more general practice patients, both insulin and non-insulin dependent, had a mean blood glucose level of less than 11 mmol l-1 compared with patients attending clinics at hospitals A and B (P < 0.001). Glycosylated haemoglobin levels did not differ between patients attending hospital A and the general practice clinics. More non-insulin dependent and insulin dependent diabetic patients attending the general practice clinics and hospital A had been monitored satisfactorily for diabetic retinopathy (general practice clinic 68.8% and 39.7% respectively, hospital A 61.7% and 43.5%) than at hospital B (43.0% and 19.4%). Referral rates among all groups for ophthalmological assessment were similar.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
87.
What and where in human audition: selective deficits following focal hemispheric lesions 总被引:8,自引:0,他引:8
Clarke S Bellmann Thiran A Maeder P Adriani M Vernet O Regli L Cuisenaire O Thiran JP 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,147(1):8-15
A sound that we hear in a natural setting allows us to identify the sound source and localize it in space. The two aspects
can be disrupted independently as shown in a study of 15 patients with focal right-hemispheric lesions. Four patients were
normal in sound recognition but severely impaired in sound localization, whereas three other patients had difficulties in
recognizing sounds but localized them well. The lesions involved the inferior parietal and frontal cortices, and the superior
temporal gyrus in patients with selective sound localization deficit; and the temporal pole and anterior part of the fusiform,
inferior and middle temporal gyri in patients with selective recognition deficit. These results suggest separate cortical
processing pathways for auditory recognition and localization.
Electronic Publication 相似文献
88.
Adam R Clarke Robert J Barry Rory McCarthy Mark Selikowitz Christopher R Brown Rodney J Croft 《International journal of psychophysiology》2003,47(2):129-137
Stimulant medications are the most commonly-used treatments for Attention-Deficit/Hyperactivity Disorder (ADHD) in North America and Australia, although it is still not entirely known how these medications work. This study investigated the effects of stimulant medications on the EEG of children with the Inattentive type of ADHD. An initial EEG was recorded during an eyes-closed resting condition and Fourier transformed to provide absolute and relative power estimates for the delta, theta, alpha and beta bands. Theta/alpha and theta/beta ratios were also calculated. Subjects were placed on a 6-month trial of a stimulant and a second EEG was recorded at the end of the trial. Subjects were included in this study only if they showed a good clinical response during the trial. The unmedicated ADHD group had significantly greater absolute and relative theta, less relative alpha, and higher theta/alpha and theta/beta ratios than the control group. The stimulant medications resulted in a normalisation of the EEG, with changes in the theta, alpha and beta bands being most evident. These results suggest that stimulants act to increase cortical arousal in children with ADHD, normalising their EEG. 相似文献
89.
Evaluation of a fluorescence-based PCR method for identification of serogroup a meningococci 下载免费PDF全文
Standard and fluorescence-based PCR assays were developed for the identification of serogroup A meningococci by detection of the mynA gene. This assay was evaluated using bacterial cultures but provides the sensitivity required for the detection of the mynA gene from bodily fluids during meningococcal disease. 相似文献
90.
R Mahalingam P Clarke M Wellish A N Dueland K F Soike D H Gilden R Cohrs 《Virology》1992,188(1):193-197
We used polymerase chain reaction to analyze the prevalence and distribution of latent simian varicella virus (SVV) in ganglionic and nonganglionic tissues from nine African green monkeys experimentally infected with SVV. Primers specific for three different regions of the SVV genome were used for amplification. SVV DNA sequences were detected in trigeminal ganglia from seven of nine monkeys and in thoracic ganglia from seven of nine monkeys. Analysis of DNA from nonneuronal tissues of three monkeys and from adrenal glands of nine monkeys revealed the presence of SVV-specific sequences in the adrenal gland of one monkey. The results indicate that, like human varicella, SVV becomes latent primarily in ganglia at multiple levels of the neuraxis, and more than one region of the SVV genome is present in latently infected ganglia. SVV latency in primates may be a useful model for varicella latency in humans. 相似文献