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31.
In the yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe replication factor C (RF-C) plays key roles both in chromosomal DNA replication and in DNA replication checkpoint function.
At the replication fork, the five-subunit RF-C complex functions to load the trimeric polymerase accessory factor PCNA onto
DNA. PCNA then acts as a sliding clamp, tethering Pol δ to the DNA to maximise its processivity. Here we describe the cloning
of the S. pomberfc3
+ gene, encoding a homologue of the S. cerevisiae Rfc3 and human hRFC36 proteins. The 1026 bp rfc3
+ ORF is interrupted by five introns, ranging in size from 49 to 165 bp. The spliced ORF is predicted to encode a 342 amino-acid
protein that is approximately 50% identical at the amino acid sequence level to the S. cerevisiae Rfc3 and human hRFC36 proteins. As expected, S. pomberfc3
+ is an essential gene, with rfc3Δ cells being defective for DNA replication. Loss of rfc3
+ function can be rescued by heterologous expression of either the S. cerevisiae Rfc3 or human hRFC36 proteins in S. pombe.
Received: 15 October 1999 相似文献
32.
Phenotypically distinct subsets of CD4+ T cells induce or protect from chronic intestinal inflammation in C. B-17 scid mice 总被引:22,自引:0,他引:22
Powrie Fiona; Leach Michael W.; Mauze Smita; Caddie Linda Barcomb; Coffman Robert L. 《International immunology》1993,5(11):1461-1471
CD4+ T cells in the mouse can be subdivided into two fractionsbased on the level of expression of the CD45RB determinant.Previous studies have shown that these subsets are functionallydistinct. We have further characterized the properties of thesesubpopulations in vivo by injecting them into C. B-17 scid mice.The animals restored with the CD45RBhighCD4+ T cell populationdeveloped a lethal wasting disease with severe mononuclear cellinfiltrates into the colon and elevated levels of IFN- mRNA.In contrast, animals restored with the reciprocal CD45RBlowsubset or with unfractionated CD4+ T cells did not develop thewasting or colitis. Importantly, the co-transfer of the CD45RBlowpopulation with the CD45RBhigh population prevented the wastingdisease and colitis. These data indicate that important regulatoryinteractions occur between the CD45RBhigh and CD45RBlowCD4+T cell subsets and that disruption of this mechanism has fatalconsequences. 相似文献
33.
Aanesen Fiona Øiestad Britt Elin Grotle Margreth Løchting Ida Solli Rune Sowden Gail Wynne-Jones Gwenllian Storheim Kjersti Eik Hedda 《Journal of occupational rehabilitation》2022,32(2):306-318
Journal of Occupational Rehabilitation - Purpose To perform a process evaluation of a stratified vocational advice intervention (SVAI), delivered by physiotherapists in primary care, for people on... 相似文献
34.
Tania Lorena Mcwilliams Di Twigg Joyce Hendricks Fiona Melanie Wood Jane Ryan Anthony Keil 《Burns : journal of the International Society for Burn Injuries》2021,47(3):569-575
AimTo evaluate the impact of the implementation of a best practice infection prevention and control bundle on healthcare associated burn wound infections in a paediatric burns unit.BackgroundBurn patients are vulnerable to infection. For this patient population, infection is associated with increased morbidity and mortality, thereby representing a significant challenge for burns clinicians who care for them.MethodsAn interrupted time series was used to compare healthcare associated burn wound infections in paediatric burn patients before and after implementation of an infection prevention and control bundle. Prospective surveillance of healthcare associated burn wound infections was conducted from 2012 to 2014. Other potential healthcare associated infection rates were also reviewed over the study period, including urinary tract infections, pneumonia, upper respiratory tract infections and sepsis. An infection prevention and control bundle developed in collaboration between the paediatric burn unit and infection control clinicians was implemented in 2013 in addition to previous standard practice.ResultsDuring the study period a total of 626 patients were admitted to the paediatric burns unit. Healthcare associated burn wound infections reduced from 34 in 2012 to 0 in 2014 following the implementation of the infection prevention and control bundle. Pneumonia and sepsis also reduced to 0 in 2013 and 2014, however one upper respiratory tract infection occurred in 2013 and urinary tract infections persisted in 2013.ConclusionThe implementation of an infection prevention and control bundle was effective in reducing healthcare associated burn wound infections, pneumonia and sepsis within our paediatric burns unit. Urinary tract infections remain a challenge for future improvement. 相似文献
35.
Michael J. Millward David R. Newell Kally Yuen Jane P. Matthews Kathryn Balmanno Christopher J. Charlton Lindsey Gumbrell Michael J. Lind Fiona Chapman Madeleine Proctor Dorothy Simmonds Brian M. J. Cantwell A. Hilary Calvert 《Cancer chemotherapy and pharmacology》1995,37(1-2):161-167
The pharmacokinetics and pharmacodynamics of prolonged oral etoposide chemotherapy were investigated in 15 women with metastatic breast cancer who received oral etoposide 100 mg as a single daily dose for up to 15 days. There was considerable interpatient variability in the day 1 pharmacokinetic parameters: area under the plasma concentration time curve (AUC) (0–24 h) 1.95±0.87 mg/ml per min (mean ± SD), apparent oral clearance 60.9±21.7 ml/min per 1.73 m2, peak plasma concentration 5.6±2.5 g/ml, time to peak concentration 73±35 min and half-life 220±83 min. However, intrapatient variability in systemic exposure to etoposide was much less with repeated doses. The intrapatient coefficient of variation (CV) of AUC for day 8 relative to day 1 was 20% and for day 15 relative to day 1 was 15%, compared to the day 1 interpatient CV of 45%. Neutropenia was the principal toxicity. Day 1 pharmacokinetic parameters were related to the percentage decrease in absolute neutrophil count using the sigmoidal Emax equation. A good fit was found between day 1 AUC and neutrophil toxicity (R
2=0.77). All patients who had a day 1 AUC>2.0 mg/ml per min had WHO grade III or IV neutropenia. The predictive performance of the models for neutrophil toxicity was better for AUC (percentage mean predictive error 5%, percentage root mean square error 18.1%) than apparent oral clearance, peak plasma concentration, or daily dose (mg/m2). A limited sampling strategy was developed to predict AUC using a linear regression model incorporating a patient effect. Data sets were divided into training and test sets. The AUC could be estimated using a model utilizing plasma etoposide concentration at only two time points, 4 h and 6 h after oral dosing (R
2=98.9%). The equation AUCpr=–0.376+0.631×C4h+0.336×C6h was validated on the test set with a relative mean predictive error of –0.88% and relative root mean square error of 6.4%. These results suggest monitoring of AUC to predict subsequent myelosuppression as a strategy for future trials with oral etoposide.Division of Haematology and Medical Oncology, Peter MacCallum Cancer Institute, Locked Bag 1, A'Beckett St, Melbourne 3000, Australia 相似文献
36.
Wolcott-Rallison syndrome is a rare autosomal recessive condition characterized by diabetes mellitus arising in early infancy and multiple epiphyseal dysplasia. To date, nine cases have been described in the world literature. We report an affected girl who died at the age of 4 years and on whom a full autopsy was performed. In addition to neonatal diabetes mellitus and epiphyseal dysplasia, this child had mental retardation and recurrent episodes of self-limiting hepatic failure. Autopsy revealed severe pancreatic hypoplasia and markedly abnormal pancreatic histology, while histology of the bone was consistent with epiphyseal dysplasia. There was laryngeal stenosis and pulmonary hypoplasia. The heart was enlarged with mitral valve dysplasia and stenosis, left atrial dilatation, left ventricular hypertrophy, and endocardial fibroelastosis. Examination of the central nervous system showed arrhinencephaly and cerebellar cortical dysplasia. The liver showed minor histological abnormalities but no features were present to account for the recurrent hepatic failure. In addition to Wolcott-Rallison syndrome this child had a deletion at 15q11-12 in 65 of her cells. 相似文献
37.
38.
39.
Theresa H M Keegan Sally L Glaser Christina A Clarke Margaret L Gulley Fiona E Craig Joseph A Digiuseppe Ronald F Dorfman Risa B Mann Richard F Ambinder 《Journal of clinical oncology》2005,23(30):7604-7613
PURPOSE: Epstein-Barr virus (EBV) in Hodgkin's lymphoma (HL) cells has been considered as a prognostic marker for this heterogeneous disease, but studies have yielded mixed findings, likely because of selected patient series and failure to acknowledge an effect of age on outcome. This study assessed survival after HL in a population-based cohort large enough to examine the joint effects of EBV with other factors including age, sex, and histologic subtype. PATIENTS AND METHODS: Included were 922 patients with classical HL diagnosed between mid-1988 and 1997 in the Greater San Francisco Bay Area, with archived biopsy specimens assayed for EBV with immunohistochemistry and in situ hybridization. Vital status was followed through December 30, 2003 (median follow-up time, 97 months). Overall and disease-specific survival were analyzed with the Kaplan-Meier method and Cox proportional hazards regression models. RESULTS: In children less than 15 years old, EBV presence was suggestively associated (P = .07) with favorable survival. In adults aged 15 to 44 years, EBV did not affect HL outcome, although a protective effect was suggested. In older adults (45 to 96 years), EBV presence nearly doubled the risk of overall and HL-specific mortality but only for patients with nodular sclerosis (NS) histologic subtype (hazard ratio for death = 2.5; 95% CI, 1.5 to 4.3). CONCLUSION: In HL, EBV tumor cell presence is associated with better survival in young patients and poorer survival in older patients with NS, independent of other factors. Variation in outcome by age and histology could indicate biologically distinct disease entities. Evidence that EBV is a meaningful prognostic marker may have therapeutic relevance. 相似文献
40.
Reported parameters of the MTT assay vary widely, and reflect a need to optimise the assay for different cell types. The MTT assay conditions for the human B-lymphocyte-derived cell line WIL2NS were optimised for MTT incubation and formazan development. The optimised MTT assay was validated by examining the effects of the acaride amitraz on WIL2NS. In pH-buffered media in the absence of cells, MTT formed formazan spontaneously, and absorbance was proportional to both the initial concentration of MTT and the time of incubation at 37 °C. One milligram per millilitre MTT was toxic to WIL2NS cells, but the accuracy of the standard curve was reduced when only 0.2 mg/ml MTT was used. Twenty percent SDS in 0.2 M HCl was preferable to DMSO as a solvent for formazan. Exposure to 0.035% amitraz resulted in a significant reduction in WIL2NS cell numbers after only 2 h of exposure. It was concluded that 0.035% of amitraz has the potential to adversely affect lymphocytes in the systemic blood system in humans, and that an optimised MTT assay was obtained by incubating WIL2NS cells with 0.45 mg/ml MTT for 17 h, followed by addition of acidified SDS for 1 h. 相似文献