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11.
A. R. Salim 《Archives of virology》1968,23(1-2):89-95
Summary Hamster embryonic cells, in which the Naples strain of phlebotomus fever virus multiplied without cytopathic effect, continued to yield virus for at least 15 serial passages over a period of ten weeks. This carrier state was not associated with production of interferon, but the cells continued to show resistance to infection with vesicular stomatitis virus (VSV). When 3×105 carrier cells were planted on top of a monolayer of normal hamster embryonic cells and allowed to grow for three days, no plaques appeared on inoculation of VSV. When smaller numbers of carrier cells were planted in a similar manner, the number of plaques was reduced in proportion to the number of cells that were planted.This paper was part of a thesis approved for the Degree of Doctor of Philosophy at the University of London.Visiting worker on a fellowship from the University of Khartoum, Sudan. 相似文献
12.
Paternal monoallelic expression of PEG3 in the human placenta 总被引:4,自引:0,他引:4
Genomic imprinting is the phenomenon whereby mono-allelic expression of certain genes occurs depending on their parental origin. The observation that imprinting only occurs in placental mammals has led to the suggestion that it may play a role in this form of reproduction. In the present study we have investigated the pattern of expression of the human PEG3 gene in the early to term placenta, as well as the uterus and ovary, using RT-PCR, northern blot and in situ hybridization. A comparison is made with the expression of Peg3 in the mouse by histochemical staining in betageo knock out mice. We have demonstrated high levels of PEG3 in the human placenta and have localized the signal to the layer of villous cytotrophoblast cells. In contrast, the pattern of expression of Peg3 in the mouse placenta is less restricted, the message being present in all trophoblast populations. Thus, expression of PEG3/Peg3 in the human and mouse placenta is not directly comparable. We have also detected PEG3 message in the ovarian stroma. We have sequenced the human PEG3 gene from exon 3 to exon 9. By utilizing a polymorphism detected in exon 9, we have established that only the paternal allele is expressed in human placenta. Human PEG3 is therefore maternally imprinted as in mouse. 相似文献
13.
Janine Jewanraj Sinaye Ngcapu Farzana Osman Veron Ramsuran Maryam Fish Andile Mtshali Ravesh Singh Leila E Mansoor Salim S Abdool Karim Quarraisha Abdool Karim JoAnn S Passmore Lenine J P Liebenberg 《Journal of the International AIDS Society》2021,24(6)
IntroductionSemen induces mucosal changes in the female reproductive tract to improve pregnancy outcomes. Since semen‐induced alterations are likely short‐lived and genital inflammation is linked to HIV acquisition in women, we investigated the contribution of recent semen exposure on biomarkers of genital inflammation in women at high HIV risk and the persistence of these associations.MethodsWe assessed stored genital specimens from 152 HIV‐negative KwaZulu‐Natal women who participated in the CAPRISA 008 trial between November 2012 and October 2014. During the two‐year study period, 651 vaginal specimens were collected biannually (mean five samples per woman). Cervicovaginal lavage (CVL) was screened for prostate‐specific antigen (PSA) by ELISA, whereas Y‐chromosome DNA (YcDNA) detection and quantification were conducted by RT‐PCR, representing semen exposure within 48 hours (PSA+YcDNA+) and semen exposure within three to fifteen days (PSA−YcDNA+). Soluble protein concentrations were measured in CVLs by multiplexed ELISA. T‐cell frequencies were assessed in cytobrushes by flow‐cytometry, and vulvovaginal swabs were used to detect common vaginal microbes by PCR. Linear mixed models adjusting for factors associated with genital inflammation and HIV risk were used to assess the impact of semen exposure on biomarkers of inflammation over multiple visits.ResultsHere, 19% (125/651) of CVLs were PSA+YcDNA+, 14% (93/651) were PSA−YcDNA+ and 67% (433/651) were PSA−YcDNA−. Semen exposure was associated with how often women saw their partners, the frequency of vaginal sex in the past month, HSV‐2 antibody detection, current gonorrhoea infection and Nugent Score. Both PSA detection (PSA+YcDNA+) and higher cervicovaginal YcDNA concentrations predicted increases in several cytokines, barrier‐related proteins (MMP‐2, TIMP‐1 and TIMP‐4) and activated CD4+CCR5+HLA‐DR+ T cells (β = 0.050; CI 0.001 to 0.098; p = 0.046) and CD4+HLA‐DR+ T cells (β = 0.177; CI 0.016 to 0.339; p = 0.032) respectively. PSA detection was specifically associated with raised pro‐inflammatory cytokines (including IL‐6, TNF‐α, IP‐10 and RANTES), and with the detection of BVAB2 (OR = 1.755; CI 1.116 to 2.760; p = 0.015), P. bivia (OR = 1.886; CI 1.102 to 3.228; p = 0.021) and Gardnerella vaginalis (OR = 1.815; CI 1.093 to 3.015; p = 0.021).ConclusionsMore recent semen exposure was associated with raised levels of inflammatory biomarkers and the detection of BV‐associated microbes, which declined by three to fifteen days of post‐exposure. Although transient, semen‐induced alterations may have implications for HIV susceptibility in women. 相似文献
14.
15.
Jill M. Body Salim I. Butrus Daniel M. Laby M. Farooq Ashraf Andrew I. Rabinowitz D. M. Parenti 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1995,233(6):374-376
Background: Anterior segment findings in AIDS patients presenting with cytomegalovirus (CMV) retinitis have not been specifically addressed in the American literature. Methods: Our study evaluated 21 AIDS patients with CMV retinitis. Results: Nineteen (90%) of these patients exhibited corneal endothelial deposits concurrent with CMV retinitis. The endothelial deposits were microscopic, opaque, linear flecks arranged in a reticular-like fashion. Of 42 eyes evaluated, 32 (76%) demonstrated active CMV retinitis. Corneal endothelial deposits were noted in 26 (81%) of the 32 eyes with retinitis. These corneal endothelial deposits were absent in the eyes which did not have CMV retinitis. Conclusion: Meticulous examination of the retina of an HIV-positive or AIDS patient who presents with reticularly arranged, linear, flecked corneal endothelial deposits should be performed to ensure that the diagnosis of CMV retinitis can be ruled out. 相似文献
16.
Bialer Meir Hadad Salim Kadry Bashier Abdul-Hai Ali Haj-Yehia Abdulla Sterling Jeff Herzig Yaacov Yagen Boris 《Pharmaceutical research》1996,13(2):284-289
Purpose. The described structure pharmacokinetic pharmacodynamic relationships (SPPR) study explored the utilization of tetramethylcyclopropane analogues of valpromide (VPD), or tetra-methylcyclopropane carboxamide derivatives of valproic acid (VPA) as new antiepileptics.
Methods. The study was carried out by investigating the pharmacokinetics in dogs and pharmacodynamics (anticonvulsant activity and neurotoxicity) of the following three cyclopropane analogues of VPD: 2,2,3,3-tetramethylcyclopropane carboxamide (TMCD), N-methyl TMCD (M-TMCD) and N-[(2,2,3,3-tetramethylcyclopropyl)carbonyl]-glycinamide (TMC-GLD).
Results. The three investigated compounds showed a good anticonvulsant profile in mice and rats due to the fact that they were metabolically stable VPD analogues which were not biotransformed to their non-active acid, 2,2,3,3-tetramethylcyclopropane carboxylic acid (TMCA). M-TMCD was metabolized to TMCD and TMC-GLD underwent partial biotransformation to its glycine analogue N-[(2,2,3,3-tetramethylcyclopropyl)carbonyl]-glycine (TMC-GLN). Unlike TMC-GLN, the above mentioned amides had low clearance and a relatively long half life.
Conclusions. In contrast to VPD which is biotransformed to VPA, the aforementioned cyclopropane derivatives were found to be stable to amide-acid biotransformation. TMCD and M-TMCD show that cyclic analogues of VPD, like its aliphatic isomers, must have either two substitutions at the position to the carbonyl, such as in the case of TMCD, or a substitution in the and in the positions like in the VPD isomer, valnoctamide (VCD). This paper discusses the antiepileptic potential of tetramethylcyclopropane analogues of VPD which are in animal models more potent than VPA and may be non-teratogenic and non-hepatotoxic. 相似文献
17.
18.
Ali Mohamed Ali Kamunkhwala Gausi Said A. Jongo Kamaka R. Kassim Catherine Mkindi Beatus Simon Ali T. Mtoro Omar A. Juma Omar N. Lweno Conrad H. Gwandu Bakari M. Bakari Thabiti A. Mbaga Florence A. Milando Ali Hamad Seif A. Shekalaghe Salim Abdulla Paolo Denti Melissa A. Penny 《Antimicrobial agents and chemotherapy》2022,66(5)
19.
Matthew J. McQueen Peter A. Kavsak Liqin Xu Olga Shestakovska Salim Yusuf 《Clinical biochemistry》2013,46(1-2):5-9
ObjectivesPrevious work on high-sensitivity troponin I (hs-cTnI) has demonstrated that it may identify patients with stable cardiovascular disease (CVD) at risk for future myocardial infarction (MI). In this study, we assessed if hs-cTnT concentrations could also identify those stable CVD patients at high risk for future MI and other ischemic cardiac outcomes.Methodshs-cTnT (lot:153-401) was measured in specimens obtained at randomisation in the Heart Outcomes Prevention Evaluation (HOPE) study (n = 2941 stable CVD patients, 4.5 years follow-up). The primary outcome for the HOPE study (MI, stroke, or cardiovascular death) was used to identify cutoffs by receiver operating characteristic (ROC) curve analysis and was used in conjunction with the 95th and 99th percentile upper limits to construct different concentration ranges, which were assessed using log-rank tests and multivariable Cox proportional hazard models. These different concentration ranges were then assessed for the components of the primary outcome and for heart failure (HF).ResultsThe ROC derived hs-cTnT cutoff was 8 ng/L for the primary outcome. Subjects with hs-cTnT either below (8 to < 14 ng/L) or slightly above the published 99th from a healthy population (14 to 21 ng/L) had similar probability for the primary outcome. Those with hs-cTnT concentrations > 31 ng/L had the highest probability and greatest risk for future MI, HF, and cardiovascular death as compared to those with hs-cTnT concentrations < 8 ng/L.ConclusionIn patients with stable CVD disease hs-cTnT measurement identifies those at risk for MI as well as HF and cardiovascular death. 相似文献
20.
Differences in the management and prognosis of women and men who suffer from acute coronary syndromes. 总被引:4,自引:0,他引:4
Sonia S Anand Chang Chun Xie Shamir Mehta Maria Grazia Franzosi Campbell Joyner Susan Chrolavicius Keith A A Fox Salim Yusuf 《Journal of the American College of Cardiology》2005,46(10):1845-1851
OBJECTIVES: The purpose of this research was to determine if sex and gender differences in the management of acute coronary syndromes (ACS) are associated with differences in prognosis after ACS. BACKGROUND: Previous investigators have reported sex/gender differences in the management of patients with ACS, but the impact of these differences on prognosis is unclear. METHODS: We analyzed data from the Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE) trial, which enrolled 4,836 women and 7,726 men with ACS. Patients were classified into risk strata using the Thrombolysis In Myocardial Infarction (TIMI) score. RESULTS: Women underwent fewer invasive procedures including angiography, angioplasty, and coronary artery bypass graft (CABG) surgery (47.6% vs. 60.5%; p = 0.0001) compared to men. No significant differences in cardiovascular death, myocardial infarction (MI), or stroke were observed (9.8% vs. 10.9%; p = 0.04), although women were more likely than men to develop refractory ischemia and to be rehospitalized for chest pain during follow-up (16.6% vs. 13.9%; p = 0.0001). These differences were particularly evident among TIMI high-risk women. A significant interaction between TIMI risk and gender for the outcome of refractory angina and rehospitalization for angina was present. CONCLUSIONS: Compared to men, high-risk women with ACS undergo less coronary angiography, angioplasty, and CABG surgery, and while they do not have higher incidence cardiovascular death, recurrent MI, or stroke, they suffer an increased rate of refractory ischemia and rehospitalization. All high-risk women and men with ACS should receive optimal medical management, and be considered for coronary angiography with possible revascularization if their coronary anatomy warrants it. 相似文献