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Biomedical subjects

J Perry

Publications and source records attributed to J Perry.

At least 37 records · Page 2Linked to original sources
PubMed1990

Variations in the carbohydrate regions of Bordetella pertussis lipopolysaccharides: electrophoretic, serological, and structural features.

Structural and immunological differences between the two components that are usually present in unequal quantities in Bordetella pertussis endotoxin preparations and are visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis have been studied by using strains 1414, A100, and 134, all in phase I. According to analyses by both sodium dodecyl sulfate-polyacrylamide gel electrophoresis and thin-layer chromatography, the minor (8%) component of the endotoxin of strain 1414 (endotoxin 1414) appeared to be the predominating component of endotoxins A100 and 134. The masses of the carbohydrate chains isolated from endotoxin A100 and from the major component of endotoxin 1414 were 1,649 and 2,311 atomic mass units, respectively, as determined by 252Cf plasma desorption mass spectrometry. Comparison of the 1H nuclear magnetic resonance spectra of these chains established that four N-acetyl groups, an N-methyl group, and a 6-deoxy function, which characterize the nonreducing, distal trisaccharide of the glycose chain of strain 1414, were absent from that of strain A100. The antigenicity of endotoxin 1414, as measured by enzyme-linked immunosorbent assay, was higher than that of endotoxin A100, but fell below it when the glycose chain of endotoxin 1414 was deprived of seven sugars by treatment with nitrous acid. This observation suggests that at least three (distal, proximal, and intermediate) regions of the glycose chain of endotoxin 1414 carry antigenic determinants. One of these, located in the distal trisaccharide, is absent from both endotoxins A100 and 134.

Bordetella pertussis↗
PubMed1990

Methylation of DNA in megaloblastic anaemia.

Methylation of cytosine residues in DNA samples, collected before and serially after cobalamin treatment from patients with cobalamin deficiency, was studied using restriction endonucleases Hpa II and Msp I and an epsilon globin gene probe. There was no evidence of hypomethylation in any of the samples. It was concluded that although hypomethylation of metabolites such as choline occurs, that of DNA is preserved in megaloblastic anaemia.

Anemia, Macrocytic↗
PubMed1990

Below-knee amputee gait with dynamic elastic response prosthetic feet: a pilot study.

The purpose of this pilot study was to investigate some of the new dynamic elastic response (DER) prosthetic feet compared to the SACH foot and determine if any demonstrated trends of producing the most optimum gait. We investigated the gait of five below-knee amputees while wearing four different DER feet (Flex-Foot, Carbon Copy II, SEATTLE, STEN) and a standard SACH foot. Each subject used each foot for 1 month prior to in-depth gait analysis and energy expenditure testing at the Pathokinesiology Laboratory. Minimal differences in either free or fast walking were noted between the five feet. The Flex-Foot resulted in significantly different gait kinematics at the "ankle" compared to the other four feet, however, this foot did not produce an increased velocity nor an improved energy cost. The results of this pilot study indicated that during free or fast-paced walking on level ground there were no clinically significant advantages of any one of the feet tested. Based on this pilot data, recommendations are made for future studies including appropriate sample size.

Adult↗
PubMed1990

Effect of an unrestricted knee-ankle-foot orthosis on the stance phase of gait in healthy persons.

Twenty healthy women (mean age: 25 +/- 3.6 years) were studied for postural adaptations produced when walking with unrestricted knee-ankle-foot orthoses. Stride characteristics, motion, floor reaction forces and their torques, and indwelling electromyographic activity of the lower gluteus maximus, as well as the long head of the biceps femoris, vastus lateralis, and soleus muscles were all measured during barefoot and orthosis walking. Wearing a knee-ankle-foot orthosis increased stride length and decreased cadence and stance duration. The subjects walked in slightly more plantar flexion, knee flexion, and hip flexion, while increasing the duration of the corresponding floor reaction torques, resulting in an activity increase of the vastus lateralis, soleus, and biceps femoris muscles. These results, obtained in healthy subjects, show a definite effect of an unrestricted knee-ankle-foot orthosis on gait.

Adult↗
PubMed1990

Pathologic gait.

The diagnosis of gait deviations and their causes requires three levels of knowledge. First is an awareness of the functional limitations caused by each type of abnormality (contracture, muscle weakness, pain, and spasticity). Second is familiarity with normal function. Third is having a trained eye or gait analysis system that is capable of identifying the gait deviations. Once diagnosis is complete, a fourth requirement is the ability to use the findings to set up an appropriate treatment regimen.

Ankle Joint↗
PubMed1990

Validity of self-report of adaptive behavior skills by adults with mental retardation.

The validity of self-reports of 48 adults with mental retardation of daily living competency using the recently revised Vineland Adaptive Behavior Scales (Sparrow, Balla, & Cicchetti, 1984) was investigated. Self-report was compared to standard Vineland interviews of subjects' program counselors and to demonstrated competency in a real-life setting. On domains measuring adaptive skills, the subject and counselor interviews yielded highly consistent results. On the optional Maladaptive Behavior domain, however, the subjects with mental retardation underreported problematic behavior. Response validity and implications for use of self-report for program planning and placement decisions were discussed.

Activities of Daily Living↗
PubMed1989

Oxidation of 5-methyltetrahydrofolate in cobalamin-inactivated rats.

Rats were exposed to nitrous oxide, which inactivates cob(I)alamin (Cbl). As in air-breathing rats methionine administration led to the conversion of hepatic 5-methyltetrahydrofolate (MeH4 folate) into formyltetrahydrofolate. The recovery of MeH4 folate levels in liver after its oxidation initiated by methionine was noted and the rate compared with that for air-breathing rats. Oxidation of MeH4 folate was less complete and occurred more slowly in Cbl-inactivated rats as compared with controls. However, recovery of MeH4 folate levels was more rapid in Cbl inactivation. S-Adenosylmethionine did not produce a significant change in MeH4 folate levels in Cbl-inactivated rats, whereas it did so in air-breathing animals.

Animals↗
PubMed1989

Regulation of 5-methyltetrahydrofolate synthesis.

After an intraperitoneal injection of 100 mumol of methionine to rats, there is rapid oxidation of the methyl group of hepatic 5-methyltetrahydrofolate to formate and CO2. Recovery of the methylfolate level starts 2.5 h after the methionine injection, when the hepatic methionine level and the S-adenosylmethionine/S-adenosylhomocysteine ratio have returned to baseline values. S-Adenosylmethionine concentration is still elevated at this time.

Animals↗
PubMed1989

Cobalamin-folate interrelations.

Cobalamin deficiency leads to impaired folate function as demonstrated by markedly impaired single-carbon unit transfer into purine, thymidine and methionine. This occurs in the total absence of 'methylH4folate trapping'. In cobalamin deficiency there is impaired synthesis of formylH4folate and raised levels of endogenous formate in blood and liver. FormylH4folate and methionine reverse the effects of cobalamin deficiency. Methionine provides formate via its metabolism to methylthioribose. Recently it has been suggested that the neuropathy of cobalamin deficiency is due to impaired methylation but this was not confirmed. It is likely that defects demonstrated in marrow and liver are also the explanation for the effects of cobalamin deficiency in the CNS.

Anemia, Megaloblastic↗
PubMed1989

Pelvic exercise and gait in hemiplegia.

The purpose of this study was to describe and compare the gait of 20 patients with hemiplegia secondary to cerebrovascular accident (CVA) before and after a treatment regimen of resisted pelvic motions. Ten women and 10 men were studied, with a mean age of 48 years and a mean duration post-CVA of two months. Nine subjects (45%) were right hemiplegic, and 11 subjects (55%) were left hemiplegic. Treatment consisted of four sets of five repetitions each of manually resisted pelvic anterior-elevation and posterior-depression movements on the involved side. An insole footswitch system, knee electrogoniometer, and force walking aid were used in gait analysis performed before treatment, immediately after treatment (posttest 1), and 30 minutes after treatment (posttest 2). Results showed significant overall improvement in gait in posttest 1 (p less than .005) compared with the pretest. This improvement, however, was not maintained in posttest 2. Ten patients improved overall in posttest 1; only 4 patients also showed improvement in posttest 2. The major improvements seen immediately after treatment were observed in stance stability and limb advancement in the involved limb. More research is needed to identify an optimum treatment with carry-over using this technique.

Adult↗
PubMed1989

Dynamic EMG analysis of torque transfer in professional baseball pitchers.

Fifteen professional baseball pitchers underwent active pitching motion analysis of the abdominal oblique, rectus abdominis, lumbar paraspinous and gluteus maximus muscles bilaterally via surface electrode evaluation. Baseline resting and isometric maximum values were obtained and active data referenced against these for comparison. The muscle activity then was measured during the pitching sequence and analyzed in each of the five pitching phases. The abdominal oblique, lumbar paraspinous and rectus abdominis contralateral to the pitching arm and the ipsilateral gluteus maximus all had increases in activity level of 75 to 100% during the active pitching motion. Using these data indicating specific muscle group patterns with clinical and performance data, we hope to minimize injuries and maximize pitching performance.

Abdominal Muscles↗
PubMed1989

Cost-related variables: a pilot study.

The advent of prospective payment systems prompts nurses to examine cost-related factors in demonstrating savings resulting from quality care. The clinical nurse specialist plays an active role in the examination of variables influencing costs for patients within the specialty. This pilot study utilized a retrospective chart audit of 142 women falling within Diagnostic-related Group 355 (non-radical hysterectomy, age less than 70 years, without comorbid condition or complication) during 1985 to identify demographic, illness/treatment-related, and discharge variables related to charge variance. Independent (length of stay, p less than 0.001 and previous admission, p = 0.066) predictors of charge variance were found among the 14 variables studied. The value of the research as a model for other practitioners is discussed.

Costs and Cost Analysis↗
PubMed1989

The effect of the CAT-CAM above-knee prosthesis on functional rehabilitation.

Five, rehabilitated, unilateral above-knee amputees (average age, 34.4 years) using quadrilateral sockets were converted to Contoured Adducted Trochanteric-Controlled Alignment Method (CAT-CAM) sockets to determine the effect on ambulatory function. Patients were evaluated before and after conversion for subjective acceptance, gait deviations, relative femoral shaft inclination, coronal-plane hip abduction torque, and ambulatory metabolic demands. The CAT-CAM socket was subjectively rated superior by four patients. Most gait deviations improved or disappeared. Femoral shaft inclination angles improved an average of 6.5 degrees toward adduction by roentgenographic measurements in four patients. Film records suggest that the compensatory lateral trunk lean, seen in patients with quadrilateral sockets, diminished after conversion. These four patients increased their customary gait velocities, and all showed a reduction in the quantity of oxygen consumed per meter traveled by up to 50%.

Amputation, Surgical↗
PubMed1988

Functional recovery. A major risk factor for the development of postpoliomyelitis muscular atrophy.

A retrospective study was undertaken to identify potential risk factors for the development of progressive postpoliomyelitis muscular atrophy (PPMA). Patients with PPMA (n = 57) were compared with patients with a history of poliomyelitis but without a history of progressive weakness (n = 49). Patients who later developed PPMA had histories of more widespread acute paralysis, but relatively greater functional recovery. They were less disabled, and reported higher recent activity levels. Seventy-nine percent of the total variance between the PPMA and control groups could be accounted for by recovery alone (ie, severity minus disability). Functional recovery is generally attributed to reinnervation of sarcomeres by collateral sprouting from surviving lower motor neurons. Since degree of recovery predicts the risk of developing PPMA, our findings suggest that enlarged motor units may carry an increased susceptibility for dysfunction and/or degeneration.

Adult↗
PubMed1988

Energy-speed relationship of walking: standard tables.

The energy expenditure of level walking was measured in 260 normal male and female subjects walking around a 60.5m-circular outdoor track. Subjects were divided into four age groups (children, 6-12 years; teens; young adults, 20-59 years; and senior adults, 60-80 years). Oxygen consumption was measured with a modified Douglas Bag technique during the fourth and fifth minutes of each trial. Standard tables according to age and sex were derived for the average energy expenditure (rate of oxygen uptake, energy cost per meter, and heart rate) and for the gait characteristics (speed, cadence, stride length) at the subjects' customary slow, normal, and fast walking speeds. Statistical analysis was performed to determine the energy-speed relationship for the different age groups to derive normative tables for the rate of oxygen uptake throughout the range of customary walking velocities.

Adolescent↗
PubMed1988

A comparison of foot-switch and EMG analysis of varus deformities of the feet of children with cerebral palsy.

Fifty-one children with cerebral palsy who were candidates for surgery for equinovarus deformities of the foot had their gait evaluated by means of foot-switches and electromyography to determine the contribution of the anterior tibialis and posterior tibialis muscles to the deformity. Seven EMG patterns and five foot-switch patterns were identified, but there was no correlation between the EMG and foot-switch patterns. Foot-switch data alone could not identify the deforming muscles or their patterns, so are not adequate for planning surgical correction of varus feet of children with cerebral palsy.

Cerebral Palsy↗