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M A Hirsch

Publications and source records attributed to M A Hirsch.

13 recordsLinked to original sources
PubMed2004

[How reliable are data from 3d-gait analysis].

AIM: The aim of the present study was to collect preliminary data to determine the test-retest reliability in healthy subjects using 3-dimensional computerised gait analysis. METHOD: Ten healthy subjects (6 females, 4 males) were tested using a 3-dimensional computerized gait analysis system (VICON 512, Oxford Metrics). There were two trials within a 2-hour period in which kinetic, kinematic and time-distance data were collected. Markers were removed after the first trial and reapplied for the second trial and Pearson's correlation coefficients were calculated. RESULTS: The correlation coefficients were all positive and high for time-distance (r = 0.86-0.99), sagittal plane kinematics (r = 0.86-0.98) and power (r = 0.90-0.98) parameters, indicating excellent reliability of these measures. Correlation coefficients for frontal and transverse plane kinematics were lower (r = 0.59-0.89). The lowest correlation coefficient values were obtained for transverse plane measures at the hip joint indicating poor reliability of this measure in healthy subjects. CONCLUSION: The results suggest excellent test-retest reliability using 3-dimensional computerized gait analysis, especially in the sagittal plane. Therefore this method is a very valuable tool in the analysis as well as in the outcome evaluation of conservative and operative procedures in movement disorders

Adult↗
PubMed1996

The multicomponent nature of equilibrium in persons with parkinsonism: a regression approach.

Lower extremity strength and joint range of motion, body sway, and electromyography responses have all been determined to be factors in balance control of healthy older individuals. The purpose of this study was to identify variables which effect balance control (equilibrium scores) of persons with Parkinsonism, and examine their relationships and predictive abilities. The composite equilibrium score from the sensory organization protocol of the Equitest was used as the dependent variable for the regression analysis. The independent variables included: 1) strategy score; 2) path sway during voluntary body displacement; 3) percent peak torque of knee flexion relative to that of knee extension (%PTKFKE); 4) peak torque of inversion of the ankle at (PTINV); 5) dorsiflexion ROM; and 6) medium loop latency (EMG). The model produced a significant overall relationship accounting for 88% of the variability in equilibrium scores. Positive and significant coefficients indicated a predicted increase in the equilibrium composite score with increases in the strategy score, PTINV and %PTKFKE. These results suggest that postural control of persons with Parkinsonism can be strongly predicted by these three variables.

Aged↗
PubMed1994

Evaluation of the immunogenicity of protein hydrolysate formulas using laboratory animal hyperimmunization.

The rabbit hyperimmunization model has previously been used to evaluate candidate hypoallergenic protein ingredients. Use of the model has been expanded to include the evaluation of protein hydrolysate formulas. Each formula's immunological reactivity was determined by ELISA measurement of formula-specific rabbit antibody. Animals hyperimmunized with formulas containing extensively hydrolyzed proteins (Alimentum, Nutramigen, and Pregestimil) generated very weak immune responses (< 100 fold antibody increase). Products containing intact or partially hydrolyzed proteins (Similac, Enfamil, Good Start, Beba HA, and Nidina HA) elicited high level (> 10,000 fold increase) immune responses. Immunogenicity results were then compared to measurements of residual antigen content (by inhibition ELISA) and clinical performance. Correlation of formula immunogenicity, antigenicity and clinical performance indicates that the rabbit model is useful for screening "hypoallergenic" formulas to predict allergenic reactivity.

Animals↗
PubMed1988

Preoperative localization of parathyroid adenomas.

During a 12-month period, 64 patients were operated on for primary hyperparathyroidism. Sixty-one had single adenomas and 3 had double adenomas. Preoperative imaging was used to localize the adenomas. Half of the patients (32 of 64) had magnetic resonance, thallium-201/technetium-99m subtraction scintigraphy, and high-resolution ultrasonography; the other 32 patients had 1 or 2 of the imaging modalities. Sensitivity and specificity of magnetic resonance imaging was 82 percent and 97 percent, respectively; the sensitivity and specificity of the other two modalities was 59 and 98 percent for subtraction scintigraphy and 73 and 98 percent for ultrasonography. The use of preoperative imaging facilitated surgical exploration, reduced operating time, and resulted in an increased number of successful operations. There were no negative explorations in this series as compared with 19 negative explorations (2.6 percent) in our prior experience with 720 operations.

Adenoma↗
PubMed1987

Use of furosemide in pregnancies complicated by oligohydramnios.

To differentiate pregnancies complicated by oligohydramnios due to intrauterine growth retardation from those due to renal agenesis, the authors administered furosemide intravenously to eight pregnant women (19-25 weeks gestation) with oligohydramnios. The fetal abdomen was scanned with ultrasound to demonstrate the fetal urinary bladder. In six fetuses, sonography failed to demonstrate the bladder: two fetuses had growth retardation with normal kidneys and bladder, and four had renal anomalies. It is concluded that administration of furosemide to the mother fails to induce diuresis in growth-retarded fetuses of 19-23 weeks gestation and that failure to see the fetal bladder after furosemide administration does not necessarily indicate absent fetal kidneys.

Amniotic Fluid↗
PubMed1979

The dissociation and separation of bovine adenohypophysial cells.

Bovine adenhypophysial tissue was dissociated by sequential enzymatic incubation in a continuous flow system. Dispersed cells separated into discrete fractions after centrifugation in isopycnic bovine serum albumin gradients. The dispersed and separated cells were prepared for microscopic identification and differential counts by centrifugal cytology. Radioimmunoassays for LH, FSH, TSH, and Prl were used to corroborate the differential counts and determine the homogeneity of the fractions. The thyrotrophs banded at an average density (rho) of 1.0417, the FSH-secretory cells at rho = 1.0597, the LH-secretory cells at rho = 1.0458, and the Prl-secretory cells at rho = 1.0126. A 7-16 fold enrichment of different cell populations was possible. In bovine hypophyses each hormone appears to be formed by specific cells: the average TSH concentrations of the thyrotrophs were 5.1 pg/cell for LH- and FSH concentration were 4.7 and 4.9 pg/cell for LH- and FSH-secreting cells, respectively. The average Prl concentration was 4.9 pg/cell for Prl-secreting cells.

Animals↗
PubMed1979

A simple and sensitive nonradioactive method for the detection of urinary human chorionic gonadotropin and diagnosis of early human pregnancy. II. Single-unit test.

A simple, sensitive, and reliable single-unit nonradioactive method for the detection of human chorionic gonadotropin (hCG) in concentrated urine and the diagnosis of early pregnancy is reported. This unit, presently termed the Ayerst pregnancy test kit (APTK), consists of four components: a sampler-filter paper cone, an ultrafilter-concentrator to which a vial holder is attached, a support stand with a mirror, and an immunologic reagent vial. In the APTK, 5 to 6 ml of urine were sampled, filtered, and concentrated, and the hCG in the retentate was detected by Ayerst immunologic reagents [APTK(AY)] and by the Pregnosticon "All In" [APTK(P)]. Some of the unconcentrated urine samples (0.1 ml) were also tested in hemagglutination inhibition tests (HIT) using Ayerst [HIG(AY)] and Pregnosticon "All In" [HIT(P)] reagents. Urine samples from pregnant, nonpregnant (ovulating and nonovulating), perimenopausal, and menopausal women were tested. It was found that the APTK(AY) and APTK(P) were significantly more sensitive and reliable than the HIT(AY) and HIT(P) in detecting low levels of urinary hCG for early diagnosis of pregnancy. The sensitivity and specificity of the APTK(AY) were better than those of the APTK(P). The APTK(AY) give significantly more correct positive and negative results than the other tests performed simultaneously. The APTK(AY) is simpler and safer than the serum radioimmunoassays and radioreceptor assay presently used to detect low levels of hCG for the early diagnosis of pregnancy and other hCG-producing states.

Chorionic Gonadotropin↗
PubMed1977

Pancreatic somatostatinoma. Clinical features and physiological implications.

The first case of a tumour producing somatostatin-like immunoreactivity and bioactivity is presented. The pancreatic tumour was composed of cells indistinguishable from islet D cells. Radioimmunoassay of blood-samples obtained by tumour-vein catheterisation revealed very high levels of somatostatin immunoreactivity. On gel chromatography tumour extracts were found to contain at least 4 different immunoreactive components, one of which eluted in the position of synthetic somatostatin. Extracts from the tumour were potent in inhibiting insulin and glucagon secretion from isolated perfused porcine pancreas. Clinical abnormalities included hypochlorhydria, steatorrhoea, and diabetic glucose tolerance. Conceivably some of these abnormalities may be related to somatostatin hypersecretion from the pancreatic tumour.

Antigen-Antibody Reactions↗
PubMed1976

Blockade of LH-RH induced ovulation in immature rats by LH-RH antiserum.

An in vivo method for the determination of biological potency of luteinizing hormone-releasing hormone (LH-RH) antiserum is described. The procedure involves antiserum blockade of LH-RH induced ovulation in immature rats primed with pregnant mare's serum. A modified method for the induction of LH-RH antibodies in rabbits is also detailed.

Animals↗