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21.
C R Paterson 《British medical journal (Clinical research ed.)》1987,295(6591):213-214
22.
We investigated anaerobic threshold (< theta(L)) gas exchange kinetics and maximal oxygen uptake (VO2,max) among older men with reduced left ventricular end-diastolic filling (LVDF). Ten men (mean age, 73 years) with LVDF impairment and low fitness, but without other cardiovascular dysfunction were studied. Treatments compared to control included: 5 days, high intensity exercise training protocol; 5 days, calcium channel blockade (240 mg verapamil); 21 days, detraining/washout; and 5 days, combined treatments. Results indicated no changes in resting left ventricular systolic function with any treatment. Significant resting diastolic function changes included increased early:late flow velocity (control, 0.87; training, 1.28; verapamil, 1.32), and a decreased isovolumic relaxation time (control, 0.10 s; training, 0.08 s; verapamil, 0.08 s). The combined treatments were not additive. Sub-threshold oxygen uptake kinetics (tauVO2, s) were significantly faster following either training or verapamil (tauVO2,control, 62+/-12; tauVO2,training, 44+/-9; tauVO2,verapamil, 48+/-10) and combined treatments (tauVO2, 41+/- 8). V O2,max (ml kg(-1) min(-1)) was significantly increased (control, 21.8+/-2.2; training, 27.3+/-2.2; verapamil, 25.2+/-3.4; combined treatments, 26.9+/-2.3). Increasing ventricular preload with either exercise training or calcium channel blockade was coincident with faster tauVO2 and increased VO2,max. 相似文献
23.
Dr. C. Isaacson A. C. Paterson S. D. Berson 《Virchows Archiv : an international journal of pathology》1979,385(1):61-66
Summary Most series in Africa show a high percentage of hepatitis B surface Hepatitis antigen in hepatocellular carcinoma. Two groups of cases were investigated in this study. The one was derived from the autopsy material at Baragwanath hospital from subjects who had lived in Soweto, a large Black urban town. The second group consisted of male Black mineworkers generally originating from rural areas. A combination of the aldehydefuchsin stain and immunoperoxidase technique was used. The two groups showed totally different results. The Baragwanath series consisted of 24 hepatocellular carcinomas of which only 4 (17%) were HBsAg positive. Of the 24 cases, 14 had cirrhosis of which 9 were macronodular and 5 micronodular. Ten of these cases showed heavy iron overload. The series of male Black mineworkers comprised 22 cases of which 16 (72%) were HBsAg positive. Twelve of the 22 cases showed a macronodular cirrhosis and there were no micronodular cirrhoses. Only one case showed severe iron overload. These findings delineate two different populations of hepatocellular carcinoma in Southern Africa. 相似文献
24.
Analysis of the butyrylcholinesterase gene and nearby chromosome 3 markers in Alzheimer disease 总被引:3,自引:0,他引:3
Brindle N; Song Y; Rogaeva E; Premkumar S; Levesque G; Yu G; Ikeda M; Nishimura M; Paterson A; Sorbi S; Duara R; Farrer L; St George-Hyslop P 《Human molecular genetics》1998,7(5):933-935
The K-variant of butyrylcholinesterase (BCHE-K) recently has been reported
to be associated with Alzheimer disease (AD) in carriers of the epsilon4
allele of the apolipoprotein E (APOE) gene. We have re- examined the
frequency of the BCHE-K allele in a large data set of both sporadic and
familial cases of AD disease, and we have also examined the segregation of
three genetic markers on chromosome 3 near BCHE . Our data neither support
an association of BCHE-K with sporadic or familial AD, nor do they suggest
the existence of another gene nearby on chromosome 3 as a common cause of
familial AD.
相似文献
25.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献
26.
Lucy SD Hughson RL Kowalchuk JM Paterson DH Cunningham DA 《Experimental physiology》2000,85(2):227-237
Neural mediation of the human cardiac response to isocapnic (IC) steady-state hypoxaemia was investigated using coarse-graining spectral analysis of heart rate variability (HRV). Six young adults were exposed in random order to a hypoxia or control protocol, in supine and sitting postures, while end-tidal PCO2 (PET,CO2) was clamped at resting eucapnic levels. An initial 11 min period of euoxia (PET,O2 100 mmHg; 13.3 kPa) was followed by a 22 min exposure to hypoxia (PET,O2 55 mmHg; 7.3 kPa), or continued euoxia (control). Harmonic and fractal powers of HRV were determined for the terminal 400 heart beats in each time period. Ventilation was stimulated (P < 0.05) and cardiac dynamics altered only by exposure to hypoxia. The cardiac interpulse interval was shortened (P < 0.001) similarly during hypoxia in both body positions. Vagally mediated high-frequency harmonic power (Ph) of HRV was decreased by hypoxia only in the supine position, while the fractal dimension, also linked to cardiac vagal control, was decreased in the sitting position (P < 0.05). However, low-frequency harmonic power (Pl) and the HRV indicator of sympathetic activity (Pl/Ph) were not altered by hypoxia in either position. These results suggest that, in humans, tachycardia induced by moderate IC hypoxaemia (arterial O2 saturation Sa,O2 85 %) was mediated by vagal withdrawal, irrespective of body position and resting autonomic balance, while associated changes in HRV were positionally dependent. 相似文献
27.
Prime SS Eveson JW Stone AM Huntley SP Davies M Paterson IC Robinson CM 《The Journal of pathology》2004,203(4):927-932
This study examined the behaviour of nine human malignant oral keratinocyte cell lines following orthotopic transplantation to the floor of the mouth of athymic mice. Tumourigenesis, local spread, and metastatic dissemination were correlated with known cellular responses to transforming growth factor-beta 1 (TGF-beta 1). Six of nine cell lines were tumourigenic; four of these cell lines showed local spread which was characterized by vascular and bone invasion. Metastatic spread was uncommon, with only 9% of animals with primary tumours developing metastases and these were almost exclusively found in the regional lymph nodes; there was one pulmonary metastasis and no liver deposits. Tumour cell behaviour did not reflect the clinical stage of the original tumours. Cell lines that were resistant to TGF-beta 1-induced growth inhibition were more likely to form primary tumours, exhibit local spread, and metastasize than cells that were growth-inhibited by the ligand. The data demonstrate that tumourigenicity and tumour behaviour in this orthotopic mouse model varied between cell lines and that the pattern of local invasion and metastasis was similar to that seen in human oral cancer. Furthermore, cell lines that were refractory to the growth inhibitory effects of TGF-beta 1 behaved more aggressively than cells that underwent ligand-induced cell-cycle arrest. 相似文献
28.
Dr. Yvonne Paterson 《Immunologic research》1998,17(1-2):191-207
Our studies are mainly focused on developing strategies of immune regulation. In the case of infectious and neoplastic disease,
our approach is to upregulate cell-mediated immunity to viral of tumor antigens using an intracellular bacterium as a vector
for targeting these antigens to the major histocompatibility complex (MHC) class I and class II pathways of antigen processing,
in addition to exploiting the adjuvant properties of the vector to stimulate innate immunity. In the area of autoimmunity,
we are attempting to downregulate the immune response by specific immune intervention directed against autoreactive T cells.
In these studies we use murine models for multiple sclerosis. Our approach is to use both rationally designed T cell receptor
(TCR) peptide analogs and recombinant viral vectors that express TCR components to regulate the disease. 相似文献
29.
Paterson Y 《Immunologic research》2003,27(2-3):451-462
Our laboratory is interested in the properties of proteins that render them immunogenic, and how such immunogenicity may be
modulated in vivo. We are attempting to enhance the immune response in the design of more effective vaccines against viral
diseases, such as HIV, and against tumor antigens expressed on breast, ovarian, and cervical cancer and B cell lymphomas.
Our main approach is to use a facultative intracellular bacterium, Listeria monocytogenes, which has the unusual ability to live and grow in the cytoplasm of the cell and is thus an excellent vector for targeting
passenger antigens to the major histocompatibility complex (MHC) class I pathway of antigen processing with the generation
of authentic cytotoxic T lymphocytes (CTL) epitopes. In the field of tumor immunotherapy, we are also developing nonliving
vaccine vectors for tumor antigens. 相似文献
30.