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H Skinner

Publications and source records attributed to H Skinner.

12 recordsLinked to original sources
PubMed2004

Cerebral haemodynamics in patients with chronic renal failure: effects of haemodialysis.

BACKGROUND: We measured middle cerebral artery (MCA) flow velocity (FV), dynamic pressure autoregulation, and carbon dioxide reactivity (CRCO(2)) in patients with chronic renal failure before and after haemodialysis using transcranial Doppler ultrasonography. METHODS: Twelve patients on long-term haemodialysis were recruited. MCA FV was measured continuously. The transient hyperaemic response test was used to assess cerebral autoregulation, and per cent change in FV per kPa change in end-tidal carbon dioxide was calculated to assess CRCO(2). All measurements were recorded before and after haemodialysis. RESULTS: MCA FV (mean [sd]) decreased from 57 (10) cm s(-1) before to 46 (13) cm s(-1) after haemodialysis (P<0.01). The transient hyperaemic response ratio (THRR) was (mean [sd]) 1.29 (0.13) before haemodialysis and did not change significantly following haemodialysis (1.36 [0.10]). CRCO(2) was 21.7 (8.3)% kPa(-1) before haemodialysis and remained unchanged afterwards (20.9 [3.8]% kPa(-1)). Values in normal subjects for MCA FV, THRR and CRCO(2) are 56 (12) cm s(-1), 1.26 (0.13) and 22 (6)% kPa(-1), respectively. CONCLUSIONS: MCA FV decreases significantly after haemodialysis. Dynamic pressure autoregulation and CRCO(2) remain normal in patients with chronic renal failure, and are not altered significantly by haemodialysis.

Adult↗
PubMed2001

Identification and characterization of differentially methylated CpG islands in pancreatic carcinoma.

To identify CpG islands differentially methylated in pancreatic adenocarcinoma, we used methylated CpG island amplification (MCA) coupled with representational difference analysis. Of 42 CpG islands identified by MCA/representational difference analysis, 7 CpG islands [methylated in carcinoma of the pancreas (MICP)] were differentially methylated in a panel of eight pancreatic cancer cell lines compared with normal pancreas. In a larger panel of 75 pancreatic adenocarcinomas, these 7 MICPs (ppENK, Cyclin G, ZBP, MICP25, 27, 36, and 38) were methylated in 93, 3, 9, 15, 48, 19, and 41% of cancers, respectively, by methylation-specific PCR but not in any of 15 normal pancreata. In pancreatic cancer cell lines, methylation of ppENK, a gene with known growth suppressive properties, was associated with transcriptional silencing that was reversible with 5-aza-2'-deoxycytidine treatment. Relationships between the methylation patterns of pancreatic adenocarcinomas and their clinicopathological features were also determined. Larger pancreatic cancers and those from older patients (P = 0.017) harbored more methylated loci than smaller tumors and those from younger patients (P = 0.017). ppENK, MICP25, and 27 were variably methylated in normal gastric, duodenal, and colonic mucosae. These data indicate that aberrant methylation of ppENK and its transcriptional repression is a common event in pancreatic carcinogenesis.

Adenocarcinoma↗
PubMed1995

Structural relationships between social support and coping.

Relationships between social support and coping were examined over a one-year period in a sample (n = 120) exposed to a specific stressor (i.e. a spinal cord injury). Two issues were evaluated: (1) patterns of social support and coping over time; and (2) the direction of the effects of coping on social support or vice versa. Subjects had incurred a spinal cord injury within the preceding year, completed their rehabilitation, and returned to the community. They were assessed at 1, 4 and 12 months post-discharge to capture possible changes in patterns of social support and coping. Covariance structure modelling indicated a single-factor construct based on three measured subscales for social support (instrumental/informational/emotional), and for coping (problem-oriented/perception-oriented/emotion-oriented). While the factor structure of coping was invariant over time, the structure of social support changed from a high concentration of informational support at one month to a higher saturation of emotional support at 4 and 12 months, potentially reflecting changes in the salience of different components of the network. The perceived availability of social support was seen to have direct effects on future coping. At one month, social support had a direct positive effect on coping at four months. However, at four months social support had a negative effect on coping at 12 months, which may reflect a change in the structure of the social support construct itself. That is, as the factor structure of social support varied with time, coping may also have been influenced by differing perception of one's needs and circumstances. Thus, the study provides evidence for the dynamic effects of social support on coping, depending on one's stage in the process of long-term adjustment. The findings underscore the interplay between social support and coping, and the need for future research and practical applications to recognize temporal effects on the relationships between these two complex constructs.

Activities of Daily Living↗
PubMed1995

Assessing inter- and intrapersonal resources: social support and coping among adults with a disability.

A promising model for addressing community reintegration and adjustment following disability is the stress-outcome model. In spite of demonstrated applicability, this model has found little support among clinicians and researchers in the rehabilitation field. One reason for this may be the lack of explicit conceptual and operational definitions for the central constructs of the model. This paper presents theoretical and measurement models for two such constructs which are considered buffers or mediators in the stress-outcome relationship: social support and coping. Issues associated with each construct are explored, with reference particularly to people with disabilities. Following a synthesis of the literature, models for each construct were proposed that represented the two constructs as each having a parallel three-factor structure. Using a sample of 120 spinal cord-injured adults from across Ontario, data were collected on existing instruments which measure the two constructs of interest (Interpersonal Support Evaluation List, Ways of Coping Questionnaire). Face-to-face interviews were conducted in participants' homes at 1, 4, and 12 months post-discharge from rehabilitation, in order to capture the period of initial community readjustment and reintegration. Psychometric evaluation of the measurement models included item analysis, factor analysis, and reliability assessment. These analyses provided empirical support for the three-factor structure for both constructs, as well as a second-order general factor for social support. Recommendations for revisions of the scales and further development of the measurement models were made, and the revised measures were discussed in terms of theoretical and research implications.

Adaptation, Psychological↗
PubMed1992

Lower-limb proprioception in above-knee amputees.

A proprioception measurement system was designed and constructed to evaluate lower-limb knee joint proprioception in ten above-knee amputees. The system permitted the testing of subjects in a position simulating late swing phase of gait. The threshold for detection of slow passive motion and the ability to reproduce specified lower-limb positions were recorded for the sound and the prosthetic limbs of the subjects. A significant difference was detected between prosthetic and sound limb passive motion detection threshold; however, no difference was found between prosthetic and sound limb passive motion reproduction. This finding suggests the importance of hip joint motion appreciation in the amputees' proprioception of the prosthetic knee joint when these motions are associated. Prosthetic limb passive motion reproduction error decreased with age, suggesting that the amputees may improve their ability to use remaining lower limb proprioceptive mechanisms to compensate for the loss of anatomic knee joint structures.

Adult↗
PubMed1984

The Process Model of Family Functioning.

The Process Model of Family Functioning differs from the McMaster Model of Family Functioning and their common source, the Family Categories Schema, by its increased emphasis on the dynamic interaction between the major dimensions of family functioning, and by its stress on the interface between intrapsychic subsystems and the interpersonal dimensions of the family system. A model of family process rather than family structure, it defines six universal criteria of family functioning. It describes the processes involved in each along with the content components and the critical aspects of each. A self-report test developed from the model (FAM-III) is being widely used both as a research tool and as a clinical adjunct. Tests to define its validity and reliability continue.

Adaptation, Psychological↗