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21.
R. B. Biggs R. M. Hanley P. R. Morrison F. W. Booth 《Mechanisms of ageing and development》1991,60(3):285-293
The concentration of mitochondria decrease in the heart as rodents age from maturity to senescence. The reason for this change is not known. One purpose of the present study was to determine if cytochrome c mRNA, representative of proteins of the inner mitochondrial membrane, decreased in the hearts of Fischer 344 rats as they aged from 12 to 24 months. Twenty-two percent less cytochrome c mRNA existed per given quantity of extracted RNA from the heart in 24-month-old rats as compared with the 12-month-old group. No change in the quantities of cardiac -actin mRNA, Ca2+/calmodulin protein kinase II mRNA or 18S rRNA was noted between 12- und 24-month-old hearts. Thus, the decrease in cytochrome c mRNA suggests that decreased in mRNAs for proteins of the inner mitochondrial membrane could play some role in the diminished concentration of mitochondria that exists in the senescent heart. 相似文献
22.
Alleles of RUNX2/CBFA1 gene are associated with differences in bone mineral density and risk of fracture. 总被引:4,自引:0,他引:4
Tanya Vaughan Julie A Pasco Mark A Kotowicz Geoff C Nicholson Nigel A Morrison 《Journal of bone and mineral research》2002,17(8):1527-1534
The aim of this study was to determine if DNA polymorphism within runt-related gene 2 (RUNX2)/core binding factor A1 (CBFA1) is related to bone mineral density (BMD). RUNX2 contains a glutamine-alanine repeat where mutations causing cleidocranial dysplasia (CCD) have been observed. Two common variants were detected within the alanine repeat: an 18-bp deletion and a synonymous alanine codon polymorphism with alleles GCA and GCG (noted as A and G alleles, respectively). In addition, rare mutations that may be related to low BMD were observed within the glutamine repeat. In 495 randomly selected women of the Geelong Osteoporosis Study (GOS), the A allele was associated with higher BMD at all sites tested. The effect was maximal at the ultradistal (UD) radius (p = 0.001). In a separate fracture study, the A allele was significantly protective against Colles' fracture in elderly women but not spine and hip fracture. The A allele was associated with increased BMD and was protective against a common form of osteoporotic fracture, suggesting that RUNX2 variants may be related to genetic effects on BMD and osteoporosis. 相似文献
23.
Ganglioside (GM1) treatment of CD4+ human CEM lymphoma cells stimulated transient phosphoinositide (PI) breakdown, production of inositol phosphates (IP), protein phosphorylation and rapid decrease of CD4 surface expression. A comparison between the actions of GM1 and other agents that affect these signal transduction pathways demonstrated a distinct mechanism for GM1-induced decrease of CD4. GM1 stimulated both phospholipase C activity and protein phosphorylation but had no effect on either cellular cAMP levels or tyrosine kinase activity. Phorbol myristate acetate (PMA) stimulated protein phosphorylation and caused a significant decrease in surface display of CD4. Both of these processes were blocked by pretreating cells with the protein kinase C (PKC) inhibitor H7. These results demonstrate that GM1 stimulates PI turnover and induces a rapid decrease of CD4 surface expression by processes that do not activate adenylate cyclase or tyrosine kinase. They further demonstrate that the mechanism for GM1-induced decrease of CD4 is distinct from the CD4 internalization processes mediated by PKC activity. 相似文献
24.
Intra-amniotic inflammation in human gastroschisis: possible aetiology of postnatal bowel dysfunction 总被引:1,自引:0,他引:1
John J. Morrison Lecturer/Senior Registrar Nigel Klein Consultant † Lyn S. Chitty Consultant Gabriella Kocjan Consultant Denise Walshe Laboratory Assistant † Mark Goulding Laboratory Assistant † Michael P. Geary Research Fellow Agostino Pierro Consultant § Charles H. Rodeck Professor 《BJOG : an international journal of obstetrics and gynaecology》1998,105(11):1200-1204
25.
26.
Cardiac tamponade is a cardiological emergency requiring prompt treatment in order to avoid a fatal outcome. It can complicate a number of medical conditions and it is important, therefore, that all practitioners are aware of its presentation, diagnosis and management. These are outlined. We suggest that, with certain specific and important exceptions, percutaneous catheter pericardiocentesis is to be recommended in the management of cardiac tamponade. We include a review of 51 consecutive cases treated at our own institution. Catheter pericardiocentesis was successful in 49 (96%) cases and 36 (80%) patients did not require any further intervention. There were no major and only two minor complications which required no additional treatment. We review previous literature concerning percutaneous pericardiocentesis. Using recommended procedures, pericardiocentesis is successful in 90-100% of cases and major complications are rare. 相似文献
27.
28.
Previous reports in the literature have described correlation of increasing repeat length with severity of the phenotype, in Kennedy syndrome. We describe male siblings with different repeat lengths, with lack of expression of the phenotype in the sibling with the longer repeat length. The phenotype was identical to motor neurone disease. There is variability of expression in Kennedy syndrome and repeat length even in siblings cannot be taken as a conclusive indicator of severity. CAG repeat length cannot be used to predict the natural history of Kennedy disease. The diagnosis of Kennedy syndrome should be considered in male patients presenting with atypical motor neurone disease. 相似文献
29.
J W Gow K Simpson A Schliephake W M Behan L J Morrison H Cavanagh A Rethwilm P O Behan 《Journal of clinical pathology》1992,45(12):1058-1061
AIM: To examine peripheral blood and skeletal muscle from patients with chronic fatigue syndrome for exogenous retrovirus. METHODS: Blood samples from 30 patients and muscle biopsy specimens of 15 patients were examined for retroviral sequences by DNA extraction, polymerase chain reaction (PCR), and Southern blotting hybridisation. Sera were examined for human foamy virus by western immunoblotting and indirect immunofluorescence techniques. RESULTS: No differences between the patient and control populations was found for any of the PCR primer sets used (gag, pol, env, and tax regions of HTLV I/II). An endogenous gag band was observed in both the patient and control groups. All sera were negative for antibody to human foamy virus. CONCLUSION: The results indicate that there is no evidence of retroviral involvement in the chronic fatigue syndrome. 相似文献
30.
W Ertel M H Morrison A Ayala I H Chaudry 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(1):70-5; discussion 75-6
Hemorrhagic shock causes a severe suppression of cellular immunity and an increased susceptibility to sepsis that may be due to increased release of prostaglandin E2 by macrophages. Since chloroquine inhibits the secretion of prostaglandin E2 by macrophages in vitro, the effects of chloroquine administration in vivo following hemorrhagic shock on macrophage prostaglandin E2 secretion and on depressed cellular immunity were examined. Inbred C3H/HeN male mice, aged 6 to 8 weeks, were bled to a mean blood pressure of 35 mm Hg, which was maintained for 60 minutes, and adequately, resuscitated. Mice then received intramuscular injections of either saline (vehicle) or chloroquine (10 mg/kg of body weight). Prostaglandin E2 in macrophage supernatants (radioimmunoassay) concanavalin A-dependent splenocyte proliferation, and interleukin 2 in splenocyte supernatants (CTLL 20 interleukin 2-dependent proliferation) were determined 2 or 24 hours later. Hemorrhage caused a significant decrease of splenocyte proliferation (47%) and interleukin 2 release (49%) at 24 hours, while prostaglandin E2 secretion from macrophages was elevated at 2 hours. Chloroquine treatment attenuated depression of splenocyte functions and reduced prostaglandin E2 release. Furthermore, chloroquine treatment decreased the mortality of septic mice after hemorrhage to levels comparable with those of sham-operated mice. Thus, chloroquine may be a useful adjunct in the clinical setting for the treatment of shock-induced immunodepression and increased susceptibility to sepsis following hemorrhage. 相似文献