Search PubMed⌕ Search

Biomedical subjects

M B Shapiro

Publications and source records attributed to M B Shapiro.

At least 37 records · Page 2Linked to original sources
PubMed1995

Feedforward postural adjustments in a simple two-joint synergy in patients with Parkinson's disease.

Patients with Parkinson's disease, age-matched controls and young control subjects performed discrete elbow or wrist movements in a sagittal plane under the instruction to move one of the joints "as fast as possible." Relative stability of the other, postural joint was comparable in all 3 groups, while movement time was the highest in the patients and the lowest in young controls. Typically, EMG patterns in both muscle pairs acting at the joints demonstrated a commonly observed "tri-phasic" pattern. A cross-correlation analysis of the EMGs confirmed virtually simultaneous bursts in the wrist and elbow flexors and in the wrist and elbow extensors. In all 3 groups, there were no signs of anticipatory activation of postural muscles in about 90% of movements. We consider postural anticipation not a separate process, but a separate peripheral pattern of a single control process that may involve a number of joints and muscles. We conclude that the postural deficits in Parkinson's disease are not related to a basic deficit in the ability to generate feedforward postural adjustments but to other factors that may include the specificity of maintaining the vertical posture in the field of gravity.

Aged↗
PubMed1995

Emergency cricothyrotomy: a reassessment.

The Medical College of Georgia Level I Trauma Center admitted 5603 adult trauma patients from January 1, 1989 through June 30, 1993. Cricothyrotomy was required in 66 of 525 patients who required emergency airway control but could not be intubated nonsurgically in an expeditious manner. There were three major complications (thyroid cartilage laceration, significant hemorrhage, and failure to obtain a surgical airway) involving two patients, but each resolved without sequelae. Twenty-six patients with cricothyrotomy survived their hospital course, of which seven had decannulation of the cricothyrotomy without further airway procedures, and 19 had conversion to tracheostomy. No patient had clinically significant morbidity from the cricothyrotomy, whether with or without a subsequent tracheostomy. Surgical cricothyrotomy remains an important technique with low morbidity for selected trauma victims needing emergency airway control.

Adult↗
PubMed1994

Visual disturbances associated with oval-optic poly(methyl methacrylate) and round-optic silicone intraocular lenses.

A prospective, randomized, double-masked clinical trial of 182 patients compared the frequency of visual disturbances associated with two small incision intraocular lenses (IOLs): the Alcon MZ20BD 5 mm x 6 mm oval-optic poly(methyl methacrylate) (PMMA) IOL and the STAAR AQ1016 round-optic silicone IOL. The samples were similar at baseline. There were no significant differences in visual acuity, mean keratometric cylinder, or surgically induced cylinder between the two groups postoperatively. Patients completed a satisfaction questionnaire and visual symptom inventory of ten items three months postoperatively. Those with the oval-optic PMMA IOL reported significantly more visual symptoms than those with the round-optic silicone IOL (P = .03). The oval-optic group reported three symptoms more frequently: reflections, halos or rings around lights, and objects at arm's length appearing blurry (P < or = .010). The status of the fellow eye (cataract or pseudophakic) did not differ by randomization group, and the distribution of visual symptoms did not differ by status of the fellow eye. Frequency and severity of visual complaints were modest overall; only 1% in each group was unsatisfied with the visual results.

Adult↗
PubMed1994

Extracorporeal life support for respiratory failure after multiple trauma.

Respiratory failure may complicate multiple trauma and can add significant morbidity, mortality, and cost to the care of such patients. We used extracorporeal life support (ECLS) to treat 24 patients with multiple trauma who, after their injury, developed respiratory failure refractory to conventional ventilatory management. Injuries in these patients were the result of motor vehicle crashes (16 patients), pedestrian versus car collisions (3 patients), gunshots (2 patients), stabs (1 patient), and a recreational vehicle crash (1 patient). Patients were placed on venovenous or venoarterial ECLS, using continuous systemic anticoagulation with heparin, and percutaneous cannulation where possible. Average time on ECLS was 287 +/- 43 hours (12 +/- 1.8 days). The major complication was bleeding, which occurred in 75% of patients. Fifteen patients survived to be discharged from the hospital (63% survival). Early intervention (mechanical ventilation < or = 5 days prior to ECLS) was associated with good outcome. Despite risks of anticoagulation in patients with multiple injuries, ECLS can be life-saving in cases of respiratory failure refractory to conventional mechanical ventilation.

Adult↗
PubMed1994

A prospective evaluation of Unilens soft multifocal contact lenses in 100 patients.

One-hundred patients were fit with Unilens soft multifocal contact lenses over a 2-year period. The Unilens was selected for two reasons: the initial comfort of a soft contact lens and Unilens' purported ability to correct a wide range of refractive errors with simultaneous vision optics. The goal of this study was to find a consistent and simplified multifocal contact lens system that would satisfy a majority of the patients in the study. Forty-eight patients had no previous contact lens experience, whereas 52 patients were wearing some type of single-vision contact lens. All patients were charged the clinic's customary fee for multifocal contact lens fitting with no incentives provided for participating in the study. Success rates were very similar between first time wearers and previous contact lens wearers (71% for first time wearers and 76% for previous contact wearers). Of the four base curves available, the Unilens soft multifocal contact lenses in the 8.4 base curve demonstrated the highest success rate (81%), especially in patients with up to +2.25 D add and 1.50 D or less of cylinder.

Adult↗
PubMed1994

Geriatric trauma: aggressive intensive care unit management is justified.

The United States population older than 65 years increased 21 per cent from 1980 to 1990. Attempts to characterize geriatric trauma have failed to yield a consensus on basic descriptors or physiologic parameters predictive of outcome. We reviewed the records of 170 trauma patients, aged 60 or above, admitted to our institution in a recent 50-month period. Mortality was 21.8 per cent. None of the 54 general care patients died; 79 (68%) of the 116 ICU patients survived. ICU deaths correlated with number of organ systems failing and severe head injury. Although these results justify aggressive ICU treatment, average hospital stay was 15 days, and one third of patients required skilled nursing facilities for ultimate recovery, so the resource cost is high.

Aged↗
PubMed1993

Radial keratotomy for intolerable myopia after penetrating keratoplasty.

Radial keratotomy was used to treat intolerable myopia in nine patients aged 56 to 86 years who had previously undergone penetrating keratoplasty and intraocular lens placement. The degree of myopia ranged from -5.25 to -9.25 diopters spherical equivalent before radial keratotomy. An eight-cut radial keratotomy with either a 4.0- or 4.50-mm central clear zone was performed on all patients. One year after the radial keratotomy, the spherical equivalent ranged from -1.25 to +1.63 diopters, which rendered all patients spectacle tolerant. Endothelial cell counts done before and one year after radial keratotomy demonstrated no marked loss of endothelial cell density. No complications were seen as a result of the radial keratotomy.

Aged↗
PubMed1993

Eliminating mitochondrial DNA competition for nuclear DNA primers.

Mitochondrial DNA (mtDNA) sequences were synthesized with nuclear DNA (nucDNA) sequence-tagged site (STS) primers by mismatch priming in three independent studies of the human nuclear genome. Mismatch primer binding sites on the mtDNA were identified with from 6- to 10-bp identity at the 3' ends of the primers. In two of three cases, single-stranded mtDNA copies were gel-isolated with intended nucDNA PCR products. During routine screening of the STSs, the radiolabeled gel-isolated products hybridized to polymorphic mtDNA restriction fragments. Intense signals after overnight exposure of radiolabeled PCR probes on Southern blots suggest contaminating mtDNA PCR products. The theoretical annealing temperatures of the mismatches were well below the annealing temperatures of the PCR primers, demonstrating annealing reactions driven by the molar surplus of the primers, that is, mass action. The probability that two primers (either one of a pair or both), designed to amplify nucDNA, will bind to and amplify mtDNA may be as high as 1 in 64, assuming that an identical match with only the 3' hexanucleotide is sufficient for amplification. To circumvent this problem we have developed OLIGFIND, a program that has identified the 104 of 4096 possible hexamers that are not present in human mtDNA. Our results suggest that time could be saved by designing STS primers with one of these 104 hexamers at the 3' end. OLIGFIND can also evaluate primer 3' ends for potential PCR products from mtDNA.

Base Sequence↗
PubMed1993

Extracorporeal life support for status asthmaticus.

Status asthmaticus is a life-threatening form of reactive airway disease, refractory to initial control with ordinary medical measures, sometimes requiring mechanical ventilatory assistance. In this report, we describe a patient whose bronchospasm could not be controlled with conventional measures, with severe respiratory acidosis (PaCO2 consistently > 100 mm Hg), who was successfully supported with extracorporeal life support (ECLS). During ECLS, arterial blood gas values rapidly returned to normal, and bronchospasm resolved during the subsequent 24 h. The patient was extubated hours later, and discharged to home 4 days later, neurologically normal. We believe that this represents the first application of this technology to this disease in an adult patient.

Adult↗
PubMed1992

Early experience with adult extracorporeal membrane oxygenation in the modern era.

In 1980 we stopped using extracorporeal membrane oxygenation for adults because only 1 of 20 patients treated between 1973 and 1979 survived. In October 1988 we returned to adult extracorporeal life support (ECLS) with a modified protocol including venovenous access when possible, large oxygenators for CO2 clearance, activated clotting time of 180 to 200 seconds, and case selection based on 90% mortality (30% transpulmonary shunt). Of 19 patients referred, 14 met criteria for ECLS. Three of these 14 patients with isolated respiratory failure died before ECLS could be started, and 1 patient refused ECLS and died. Ten were placed on ECLS for 2 to 24 days. Indications were pneumonia (3), post-cardiac operation (2), and adult respiratory distress syndrome (5). Five recovered and 5 died. The cause of early death was progressive pulmonary injury (3), hemorrhage (1), and ventricular arrhythmia (1). One late death occurred at 3 months secondary to intraabdominal complications related to liver transplantation. In conclusion, 10 adult patients with severe respiratory failure were treated with extracorporeal life support; 5 patients recovered lung function and 4 of these patients survived and were discharged to home. Surviving patients were typically younger and were placed on ECLS early in their disease process, emphasizing that early intervention is one key factor to a successful outcome.

Adolescent↗
PubMed1991

An evaluation of the accuracy of Assess and MiniWright peak flowmeters.

With the advent of small inexpensive peak flowmeters, the at-home monitoring of peak flow rates has become an invaluable aid in the treatment of asthmatic patients. In this study, we evaluated the performance of the MiniWright and Assess peak flowmeters for accuracy and reproducibility. Measurements were made at varying peak flow rates and compared with those obtained simultaneously by a calibrated pneumotachograph. When this segment of the study was completed, the peak flow devices were subjected to 200 uses and were then retested. Four MiniWright peak flowmeters that had been extensively used in our clinic were tested as well. The Assess peak flowmeter was more accurate than the MiniWright at low flow rates (less than 300 L/min), while the MiniWright meter was more accurate at high flow rates (greater than 400 L/min). We also found that the accuracy of the MiniWright meter deteriorated after 200 uses and worsened further after extensive use, while the Assess meter retained its accuracy after 200 uses.

Evaluation Studies as Topic↗
PubMed1989

A phenomenon-oriented strategy in depression research.

This paper discusses the presence of important uninvestigated assumptions in every aspect of depression research. It is suggested that a general phenomenon-oriented strategy might reduce the number of assumptions, if pursued in accordance with the requirements of natural science, which aims at maximizing the accuracy of our ideas about phenomena. Possible consequences of this strategy are: (1) the provisional selection of single, well-established, target and criterion variables, together with comparison variables, all suggested by special investigations and previous research results; (2) maximizing the phenomenological validity of current observation procedures, in the light of results of research into questionnaire and interview methods; (3) inclusion of hitherto neglected, but scientifically legitimate, individual-centred, experimental and longitudinal specific strategies: the strategies of choice for the investigation of psychological processes; (4) invention of tactics to facilitate the ethically acceptable use of scientific method in investigations of clinically relevant psychological phenomena; (5) explication and eventual testing of all assumptions; (6) focus upon the understanding, prediction and control of well-established clinically relevant phenomena, with theory playing a secondary role of facilitating systematic investigation; and (7) immediate restriction, and eventual cessation, of the use of current forms of psychiatric diagnosis in fundamental depression research.

Depressive Disorder↗
PubMed1988

Ophthalmic observations in lecithin cholesterol acyltransferase deficiency.

Lecithin cholesterol acyltransferase is an enzyme that esterifies free cholesterol. A complete deficiency of this enzyme results in a diffusely cloudy cornea. This deficiency is thought to be transmitted as an autosomal recessive trait. We studied a family in which four members were homozygote recessive. In the homozygote recessive condition, a central corneal haze caused by deposition of numerous minute gray dots was consistently present. In the heterozygote condition, arcuslike changes were present in some of the patients studied. We found the corneal change in the recessive state to be sensitive and specific as a marker of this condition. Heterozygotes appear to have a higher incidence of arcuslike corneal changes.

Adolescent↗
PubMed1987

RNA splice junctions of different classes of eukaryotes: sequence statistics and functional implications in gene expression.

A systematic analysis of the RNA splice junction sequences of eukaryotic protein coding genes was carried out using the GENBANK databank. Nucleotide frequencies obtained for the highly conserved regions around the splice sites for different categories of organisms closely agree with each other. A striking similarity among the rare splice junctions which do not contain AG at the 3' splice site or GT at the 5' splice site indicates the existence of special mechanisms to recognize them, and that these unique signals may be involved in crucial gene-regulation events and in differentiation. A method was developed to predict potential exons in a bare sequence, using a scoring and ranking scheme based on nucleotide weight tables. This method was used to find a majority of the exons in selected known genes, and also predicted potential new exons which may be used in alternative splicing situations.

Animals↗