PubMed Health⌕ Search

Biomedical subjects

A Wing

Publications and source records attributed to A Wing.

11 recordsLinked to original sources
PubMed1999

Integration of the hand in postural reactions to sustained sideways force at the pelvis.

In order to investigate the potential hand contribution to sideways balance, sideways pushes to the right, which subjects resisted using either the lower limbs ("hip only") or the lower limbs assisted by the right upper limb ("hand and hip"), were delivered to the pelvis. Analysis of force and electromyogram recordings from the legs, arm and hand in the hand-and-hip condition showed a close co-ordination of upper and lower limbs in terms of mean latencies and amplitudes. However, trial to trial fluctuations of forces generated by the hand and leg did not correlate, suggesting parallel pathways under central co-ordinative control.

Adult↗
PubMed1999

Impaired anticipatory finger grip-force adjustments in a case of cerebellar degeneration.

We describe adjustments in grip force as a consequence of fluctuations in inertial load force during vertical movements of the upper limb in a patient with cerebellar degeneration. Normally grip force is adapted to load-force fluctuations, in particular to the maximum load force, which occurs early in upward movements and late in downward movements. Increased grip force during movement was observed in the patient, but the timing of maximum grip force was not different between upward and downward movements. This suggests impaired cerebellar prediction of the dynamic consequences of voluntary movement.

Adaptation, Physiological↗
PubMed1998

Coordination of hand aperture with the spatial path of hand transport.

We have investigated the coordination of hand aperture with the spatial path of hand transport in prehensile movement by comparing straight prehensile movements with curved movements, in which subjects had to pass over a "via point" marked on the work surface before picking up an object in the target location. Spatial plots of hand aperture against hand transport showed that the preshaping of the hand to prepare an appropriate grasp was delayed in the curved movements relative to the straight movements, with most of the preshaping of the hand occurring after passing the via point, even when the via point occurred late in the course of the movement. The postponement of hand preshaping was apparently not due to subjects' segmenting the movement into two completely separate portions preceding and following the via point, since some degree of hand opening often occurred before the via point. We suggest that the delay in hand opening in curved movements involves a scheduling process, which uses information about hand transport to set an appropriate hand aperture.

Adult↗
PubMed1997

On the hand transport component of prehensile movements.

Jeannerod (1981) proposed that prehensile movements involve two independent visuomotor channels that are responsible for hand transport and hand aperture. In many studies, the movement of a marker placed on the wrist has been used as an index of hand transport because wrist movement is unaffected by the movements of the digits responsible for hand aperture. In the present study, the spatial paths of the wrist, index finger, and thumb of 5 adults, each performing 50 reaching movements, were measured with a WATSMART movement tracking system, and their variability was analyzed. The measures of movement variability suggest that the motor system is more concerned with thumb position than with wrist position during hand transport. Although the wrist is a technically convenient index of hand transport, the thumb may be a more appropriate index from the point of view of motor control

Journal Article↗
PubMed1997

Cell-type expression, immunolocalization, and deoxyribonucleic acid-binding activity of basic transcription element binding transcription factor, an Sp-related family member, in porcine endometrium of pregnancy.

Basic transcription element binding (BTEB) protein is a newly identified member of the C2H2 zinc finger family that also includes the transcription factors, Sp1, Sp2, Sp3, and Sp4. This family of proteins binds GC-rich motifs widely distributed in gene promoters, resulting in distinct activation or repression of transcriptional activities. Whereas Sp proteins are ubiquitously expressed, expression of BTEB appears more limited and has not been documented in the female reproductive tract of any mammalian species. This study was designed to identify and characterize the cellular distribution of BTEB in the porcine endometrium and placenta at known stages of pregnancy. Northern analysis of uterine endometrium detected BTEB mRNA that corresponds in size (5 kilobases) to that of the major BTEB transcript in rat brain. The steady-state levels of BTEB mRNA were higher (p < 0.05) in endometrium than placenta at corresponding days of pregnancy, although for each tissue, the levels did not change with pregnancy stage (p > 0.05). Luminal epithelial (LE), glandular epithelial (GE), and stromal (ST) cells isolated from pregnancy endometrium expressed the BTEB gene, but mRNA abundance varied with cell type (LE, GE > ST). Western blot analysis using an antiserum generated against the N-terminal region of a porcine BTEB fusion protein produced in Escherichia coli revealed the presence of BTEB protein only in endometrium, not in placenta. Immunohistochemical studies localized BTEB predominantly to the nuclei of endometrial GE and LE cells. Consistent with the presence of functional BTEB protein, binding to a double-stranded oligonucleotide containing multiple GC motifs was demonstrated in nuclear extracts prepared from endometrium and from endometrial LE and GE, but not ST, cells by electrophoretic mobility shift assay. These results demonstrate the preferential endometrial cell-type expression of BTEB and suggest its regulatory role in pregnancy-associated endometrial epithelial gene expression.

Animals↗
PubMed1996

Calcium, vitamin D, and the occurrence of colorectal cancer among women.

BACKGROUND: Despite evidence from animal studies for a protective effect of higher calcium and possibly vitamin D intake against colorectal cancer, epidemiologic studies have been inconclusive. PURPOSE: We investigated the associations between the intake of calcium and vitamin D and the occurrence of colorectal cancer. METHODS: In a prospective study, 89 448 female registered nurses who were free of cancer responded to a mailed, semiquantitative food-frequency questionnaire in 1980; dietary information was updated in 1984 and 1986. Through 1992, 501 incident cases of colorectal cancer (396 colon and 105 rectal cancers) were documented. As measures of exposure, we used nutrient intake in 1980 and also two measures of long-term intake on the basis of the three questionnaires: the average of intakes from the three questionnaires and consistent intakes, which were defined as high if women were in the upper tertile on all questionnaires and low if they were in the lower tertile on all questionnaires. To further characterize long-term intake, we conducted analyses excluding women who reported a change in their consumption of milk (primary source of calcium and vitamin D) in the 10 years prior to 1980. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated using the lowest quintile of intake as a reference. The Mantel extension test was used to evaluate linear trends across the categories of nutrient intake. In multivariate analyses, the trends were tested with use of the medians of the intake as a continuous variable in the logistic model. The P values for the trends were two-sided. RESULTS: On the basis of the data from the 1980 questionnaire alone, the multivariate RR for colorectal cancer for women in the upper versus the lower quintile were 0.80 (95% CI = 0.60-1.07) for dietary calcium, 0.84 (95% CI = 0.63-1.13) for dietary vitamin D (from foods only), and 0.88 (95% CI = 0.66-1.16) for total vitamin D (from foods and supplements). After the exclusion of women who reported a change in their milk intake, the RRs for colorectal cancer for the highest versus the lowest categories of average intake were 0.74 (95% CI = 0.36-1.50) for dietary calcium, 0.72 (95% CI = 0.34-1.54) for dietary vitamin D, and 0.42 (95% CI = 0.19-0.91) for total vitamin D. The corresponding RRs for the consistency analyses were 0.70 (95% CI = 0.35-1.39) for dietary calcium, 0.59 (95% CI = 0.30- 1.16) for dietary vitamin D, and 0.33 (95% CI = 0.16-0.70) for total vitamin D. CONCLUSIONS: These findings do not support a substantial inverse association between calcium intake and risk of colorectal cancer, but an inverse association between intake of total vitamin D and risk of colorectal cancer was suggested. IMPLICATIONS: Available evidence does not warrant an increase in calcium intake to prevent colon cancer, but longer-term studies of both calcium and especially vitamin D in relation to colorectal cancer risk are needed.

Adult↗
PubMed1996

Calcium, vitamin D, and dairy foods and the occurrence of colon cancer in men.

To examine the associations between intakes of calcium, Vitamin D, and dairy foods and the risk of colon cancer, the authors analyzed data from a prospective study of 47,935 US male professionals, 40-75 years of age and free of cancer in 1986. Within this cohort, 203 new cases of colon cancer were documented between 1986 and 1992. After adjusting for age and total energy intake, the authors found that the intake of calcium from foods and supplements was inversely associated with colon cancer risk (relative risk (RR) = 0.58, 95% confidence interval (CI) 0.39-087 between high and low intakes of calcium). However, after adjusting for confounding variables, they found that the trend was no longer statistically significant (p = 0.22), and the relative risk for the highest quintile group of intake was attenuated: 0.75 (95% CI 0.48-1.15). Similar results were observed for total vitamin D intake; the age- and energy-adjusted relative risk was 0.54% (95% CI 0/34-0/85) for the highest versus lowest quintile group, and this was attenuated in the multivariate model (RR = 0.66, 95% CI 0.42-1.05). The inverse association was weaker for dietary vitamin D (RR highest vs. lowest quintile = 0.88. 95% CI 0.54-1.42) and strongest for vitamin D arising from vitamin supplements (RR = 0.48, 95% CI 0.22-1.02). Thus, it is possible that other components of multivitamin use rather than vitamin D accounted for the reduction in risk. Consumption of milk and fermented dairy products was not significantly associated with the risk of colon cancer; individuals consuming two or more glasses of "whole" or skim milk per day had a relative risk of 1.09 (95% CI 0.69-1.72), compared with those who consumed "whole or skim milk less than once a month. These prospective data do not support the hypothesis that calcium intake is strongly protective against colon cancer risk, although a modest association cannot be excluded.

Adult↗
PubMed1995

Coordinated responses following mechanical perturbation of the arm during prehension.

We have investigated how the control of hand transport and of hand aperture are coordinated in prehensile movements by delivering mechanical perturbations to the hand transport component and looking for coordinated adjustments in hand aperture. An electric actuator attached to the subject's right arm randomly pulled the subject backwards, away from the target, or pushed them towards it, during a quarter of the experimental trials. A compensatory adjustment of hand aperture followed the immediate, mechanical effects of the perturbation of hand transport. The adjustment appeared to return the subject towards a stereotyped spatial relation between hand aperture and hand transport. These spatial patterns suggest how the two components may be coordinated during prehension. A simple model of this coordination, based on coupled position feedback systems, is presented.

Adult↗
PubMed1994

Coordination of aimed movements in a case of unilateral cerebellar damage.

We have studied multi-joint arm movements in a patient with right cerebellar damage. Our patient's kinetic tremor was reduced in the absence of visual feedback, but increased when performing a concurrent cognitive task. We suggest that her kinetic tremor reflects use of a slow cortical feedback circuit for error-corrections during movement. Analysing the spatial relation between hand aperture and hand transport in prehensile movements, we found preserved strategic, trial-to-trial coordination, but impaired reactive, within-trial coordination. We conclude that the proprioceptive representations provided by the normal cerebellum play an important role in coordinating multi-joint movement.

Adult↗
PubMed1982

Effect of HLA-A and HLA-B matching on survival of grafts and recipients after renal transplantation.

Data on the effect of HLA-A and HLA-B matching between unrelated donors and recipients focus mainly on graft survival. After linking the follow-up data of the European Dialysis and Transplant Association and those of the Eurotransplant Foundation, the effect of HLA-A and HLA-B matching on recipient survival could be studied. Recipients of well-matched kidneys--i.e., without mismatches for the HLA-A and B antigens--had 51 per cent graft survival at five years, whereas recipients of grafts mismatched for four antigens had 32 per cent graft survival at five years. The overall P value between the five different mismatch classes was 0.0005. Patient survival at five years was 72 per cent in recipients of a kidney without HLA-A and B mismatches and 54 per cent in recipients of a completely mismatched donor kidney (overall, P = 0.001). These results suggest that matching for the HLA antigens has a beneficial long-term effect not only on renal-allograft survival but also on patient survival.

Actuarial Analysis↗