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101.
The annexins are family of calcium-regulated phospholipid-binding proteins with diverse roles in cell biology. Individual annexins have been implicated in tumour development and progression, and in this investigation a range of annexins have been studied in colorectal cancer. Annexins A1, A2, A4 and A11 were identified by comparative proteomic analysis to be overexpressed in colorectal cancer. Annexins A1, A2, A4 and A11 were further studied by immunohistochemistry with a colorectal cancer tissue microarray containing primary and metastatic colorectal cancer and also normal colon. There was significant increase in expression in annexins A1 (P=0.01), A2 (P<0.001), A4 (P<0.001) and A11 (P<0.001) in primary tumours compared with normal colon. There was increasing expression of annexins A2 (P=0.001), A4 (P=0.03) and A11 (P=0.006) with increasing tumour stage. An annexin expression profile was identified by k-means cluster analysis, and the annexin profile was associated with tumour stage (P=0.01) and also patient survival. Patients in annexin cluster group 1 (low annexin expression) had a better survival (log rank=5.33, P=0.02) than patients in cluster group 2 (high annexins A4 and A11 expression). In conclusion, this study has shown that individual annexins are present in colorectal cancer, specific annexins are overexpressed in colorectal cancer and the annexin expression profile is associated with survival. 相似文献
102.
D K James F M Telfer N A Keating M E Blair M A Wilcox C Chilvers 《Journal of obstetrics and gynaecology》2000,20(3):226-234
A case-control study was undertaken of 471 children on the Nottingham Special Needs Register (SNR) who were born in one of the two maternity units in the city between 1987 and 1993 (inclusive). Controls were selected as the next infant born at the same hospital following each index case. The aim of the study was to identify risk factors on the Nottingham Obstetric Database for a baby subsequently appearing on the SNR. Disability was analysed by both ICD-9 coding and functional assessment. Factors which independently and significantly predicted a child's likelihood of being on the SNR were breech presentation (adjusted odds ratio (OR) = 4.0), congenital abnormality (OR=4.9), intrapartum fetal distress (OR=1.7), fetal growth restriction (OR=2.0), socioeconomic deprivation (OR=1.8), prematurity (OR=2.2), reduced fetal movements (OR=2.5) and medication in pregnancy (OR=10.4). To our knowledge the last two factors have not previously been reported as risk predictors for neurodevelopmental disability. 相似文献
103.
104.
Makuwa M Souquière S Clifford SL Telfer PT Sallé B Bourry O Onanga R Mouinga-Ondeme A Wickings EJ Abernethy KA Rouquet P Simon F Roques P 《AIDS research and human retroviruses》2004,20(10):1137-1143
The mandrill (Mandrillus sphinx) has been shown to be infected with an STLV-1 closely related to HTLV-1. Two distinct STLV-1 subtypes (D and F) infect wild mandrills with high overall prevalence (27.0%) but are different with respect to their phylogenetic relationship and parallel to the mandrills' geographic range. The clustering of these new STLV-1mnd sequences with HTLV-1 subtype D and F suggests first, past simian-to-human transmissions in Central Africa and second, that species barriers are easier to cross over than geographic barriers. 相似文献
105.
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107.
Selective pressure of antibiotic pollution on bacteria of importance to public health 总被引:6,自引:0,他引:6
Background: Many bacteria of clinical importance survive and may grow in different environments. Antibiotic pollution may exert on them a selective pressure leading to an increase in the prevalence of resistance.Objectives: In this study we sought to determine whether environmental concentrations of antibiotics and concentrations representing action limits used in environmental risk assessment may exert a selective pressure on clinically relevant bacteria in the environment.Methods: We used bacterial inhibition as an assessment end point to link antibiotic selective pressures to the prevalence of resistance in bacterial populations. Species sensitivity distributions were derived for three antibiotics by fitting log-logistic models to end points calculated from minimum inhibitory concentration (MIC) distributions based on worldwide data collated by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). To place bacteria represented in these distributions in a broader context, we performed a brief phylogenetic analysis. The potentially affected fraction of bacterial genera at measured environmental concentrations of antibiotics and environmental risk assessment action limits was used as a proxy for antibiotic selective pressure. Measured environmental concentrations and environmental risk assessment action limits were also directly compared to wild-type cut-off values.Results: The potentially affected fraction of bacterial genera estimated based on antibiotic concentrations measured in water environments is ≤ 7%. We estimated that measured environmental concentrations in river sediments, swine feces lagoons, liquid manure, and farmed soil inhibit wild-type populations in up to 60%, 92%, 100%, and 30% of bacterial genera, respectively. At concentrations used as action limits in environmental risk assessment, erythromycin and ciprofloxacin were estimated to inhibit wild-type populations in up to 25% and 76% of bacterial genera.Conclusions: Measured environmental concentrations of antibiotics, as well as concentrations representing environmental risk assessment action limits, are high enough to exert a selective pressure on clinically relevant bacteria that may lead to an increase in the prevalence of resistance. 相似文献
108.
Leroy EM Telfer P Kumulungui B Yaba P Rouquet P Roques P Gonzalez JP Ksiazek TG Rollin PE Nerrienet E 《The Journal of infectious diseases》2004,190(11):1895-1899
We used an ELISA to determine the prevalence of IgG antibodies specific for the Zaire subtype of Ebola virus in 790 nonhuman primates, belonging to 20 species, studied between 1985 and 2000 in Cameroon, Gabon, and the Republic of Congo. The seroprevalence rate of Ebola antibody in wild-born chimpanzees was 12.9%, indicating that (1) Ebola virus circulates in the forests of a large region of central Africa, including countries such as Cameroon, where no human cases of Ebola infections have been reported; (2) Ebola virus was present in the area before recent outbreaks in humans; (3) chimpanzees are continuously in contact with the virus; and (4) nonlethal Ebola infection can occur in chimpanzees. These results, together with the unexpected detection of Ebola-specific IgG in other species (5 drills, 1 baboon, 1 mandrill, and 1 Cercopithecus), may help to narrow the search for the reservoir of Ebola virus. They also suggest that future Ebola outbreaks may occur anywhere in the central African forest region. 相似文献
109.
Serum alanine aminotransferase in skeletal muscle diseases 总被引:5,自引:0,他引:5
Although elevation of the levels of serum alanine aminotransferase (ALT) following liver injury is well known, confusion exists concerning skeletal muscle injury as the cause of this rise. We reviewed the records of 16 patients who had muscle necrosis without evidence of liver disease. The patients were divided into three groups: extreme exercise, polymyositis, and seizures. All patients exhibited markedly elevated creatine kinase and lactate dehydrogenase levels consistent with muscle injury. In acute cases, aspartate aminotransferase (AST) and ALT were both elevated, and the AST/ALT ratio was greater than 3, but this ratio approached 1 after a few days because of a faster decline in AST. In conclusion, this difference in half-life accounts for the comparable AST and ALT levels in our cases with chronic muscle injury. 相似文献
110.
Paul Telfer Helen Devereux Brian Colvin Sheila Hayden Geoffrey Dusheiko Christine Lee 《Haemophilia》1995,1(1):54-58
We have conducted a controlled trial in 20 haemophilic patients in which intravenous recombinant interferon alpha-2a, 3 mega units thrice weekly, was used to treat chronic hepatitis C infection. The study endpoints included complete and paritial normalization of serum ALT, and loss of serum HCV RNA as determined by polymerase chain reaction (PCR). Interferon treatment was effective, and resulted in improvement in ALT in nine (45%) and a loss of HCV RNA in five patients (26%), but a sustained normalization of ALT has been seen in only one case. Responses were poor in those with HIV coinfection or with HCV genotype 1 (Simmonds classification). Troublesome side-effects were reported in 80%. The occurrence of a factor VIIIc inhibitor during the study was possibly an autoimmune complication of interferon. In conclusion, we have shown lower response rates than those seen in post-transfusion hepatitis C infection and suspect that current interferon regimes are unlikely to influence the natural history of HCV infection in haemophilia. Consideration should be given to trials of higher dosage interferon, and of long-term maintenance therapy for those who relapse. 相似文献