PubMed Health⌕ Search

Biomedical subjects

H Moskowitz

Publications and source records attributed to H Moskowitz.

At least 37 records · Page 2Linked to original sources
PubMed1991

Solubilization and characterization of the insect neuronal sodium channel.

Locust neuronal sodium channels were solubilized by 1% cholate and 0.2% Triton X-100, and their functionality was monitored by [3H]saxitoxin (STX) binding assays. About 40% of STX binding activity was recovered in the solubilized fraction without affecting affinity (Kd = 0.5 nM) and the time and temperature dependent STX binding activity was significantly stabilized in the presence of 20 nM STX. Partial purification by an anion exchange resin yielded a 20% recovery and a 3.5 times increase in the specific STX binding activity. Identification of the locust solubilized sodium channels by immunoprecipitation and radiophosphorylation revealed a Mr of 245,000 on SDS-PAGE. The present solubilized preparation will enable the study of the unique pharmacology of insect sodium channels.

Animals↗
PubMed1990

Sodium channel polypeptides in central nervous systems of various insects identified with site directed antibodies.

Immunoprecipitation, radiophosphorylation and SDS-PAGE autoradiography enable the characterization of sodium channel polypeptides in the central nervous system of insects belonging to four phylogenetically distinct orders: grasshoppers, cockroaches, flies and moth larvae. It has been shown that the insect sodium channels: (1) Are recognized by the previously described (Gordon et al. (1988) Biochemistry 27, 7032-7038) site directed antibodies corresponding to a highly conserved segment linking the homologous domains III and IV in the vertebrate sodium channel alpha subunits. (2) Serve as substrates for phosphorylation by cAMP-dependent protein kinase. (3) Are devoid of disulfide linkage to smaller subunits unlike sodium channels in vertebrate brain. (4) Are glycoproteins as shown in the grasshopper by the decrease of apparent molecular weight following endoglycosidase F treatment and specific binding to the lectins concanavalin A and wheat germ agglutinin. (5) Reveal a diversity with regard to their (a) apparent molecular masses which range from 240 to 280 kDa and (b) V8 proteinase digestion phosphopeptides indicating either differences in the positioning of the enzymatic cleavage and/or phosphorylation sites. These results provide the first evidence for structural diversity of sodium channel subtypes among various insect orders and are compared to their mammalian counterparts.

Amino Acid Sequence↗
PubMed1990

Drug performance sensitivity: a pilot study.

Thirty noninsomniac healthy adult men were enrolled in a multicenter pilot study to evaluate the sensitivity of psychomotor and cognitive tasks and subjective evaluation of performance and mood after treatment with flurazepam (Dalmane) 45 mg (larger than the recommended prescribing dose of 15-30 mg). This pilot study was also used to standardize testing procedures. The subjects were given either flurazepam or placebo at 72-hour intervals in a double-blind Latin square crossover design. Choice reaction time, but not simple reaction time, was drug sensitive. Divided attention and vigilance tasks were also sensitive to drug effects. Of the two cognitive tasks tested, addition was impaired by drug, but reading comprehension was not. Subjective evaluations of performance and mood states indicate that these are useful measures, but responses on the Hopkins Symptom Checklist were not influenced.

Adult↗
PubMed1990

Psychomotor performance in chronic insomniacs during 14-day use of flurazepam and midazolam.

Four skills performance (psychomotor) tasks, including simple and choice reaction time, divided attention, and vigilance, were given to 99 chronic insomniacs to determine whether the use of midazolam 15 mg, or of flurazepam 15 or 30 mg, compared with placebo would produce next-day impairment throughout a 14-day treatment period. Tests were administered during 2 baseline days and on treatment days 1 and 2 (early interval), 7 (middle interval) and 13 and 14 (late interval). Compared with placebo, performance on all four tasks was impaired by flurazepam 30 mg. The deficits associated with flurazepam 15 mg were roughly half the magnitude of those produced by flurazepam 30 mg, but these changes did not reach statistical significance for single response measures at single time intervals. Midazolam showed no consistent pattern of performance effects; however, for divided attention tracking error, there was a significant decrement. The placebo group showed flat performance curves or improved performance as a result of learning (practice effect).

Adult↗
PubMed1989

Mobile mammography: the first six-months experience at Mount Sinai Hospital.

Mount Sinai Hospital's Mobile Mammography Program, BreastCheck, is designed to screen large numbers of women for breast cancer in the greater Hartford area. Despite the American Cancer Society recommendations for screening mammography, many physicians still are not complying with these guidelines. This report details our first six-months experience. Two thousand two hundred thirty women were screened, 38 women had biopsies, and 14 cancers were detected. The overall rate of breast cancer detection is 6.3/1,000 which compares favorably with the rates from the National Breast Cancer Demonstration Detection Project (BCDDP) of 4.6/1,000.

Adult↗
PubMed1988

Effects of terfenadine, diphenhydramine, and placebo on skills performance.

The behavioral effects of the antihistamines terfenadine and diphenhydramine were compared in a placebo-controlled, double-blind crossover study. Performance of skills deemed important in safe man-machine interactions was objectively assessed one, three, and five hours after administration of test substances. The results indicate that diphenhydramine use resulted in various degrees of impairment of the ability to perform a visual-search task, a tracking task, a divided-attention task, and a vigilance task. Terfenadine users performed as well as or better than placebo-treated subjects. No differences between terfenadine and placebo were found on a subjective evaluation scale. Diphenhydramine users consistently reported feelings of impairment.

Adult↗
PubMed1988

The effects on performance of two antidepressants, alone and in combination with diazepam.

1. Ninety healthy adult men participated in a study of the effects on performance of 60 mg fluoxetine, 50 mg amitriptyline or placebo, alone and in combination with 5 mg diazepam or placebo. 2. In a 2X3 factorial design study, groups of 15 Ss received one of six possible treatment combinations. 3. Ss were tested with a battery of laboratory tests at two post-dosing times. 4. Amitriptyline impaired the performance of all tasks. When diazepam was added to the amitriptyline treatment, the impairment of three tasks increased. Diazepam alone produced impairment on two measures. 5. Fluoxetine alone impaired no task; some impairment occurred with the fluoxetine-diazepam combination.

Adult↗
PubMed1987

The methylation state of the proviruses in avian sarcoma virus transformed chick and rat cells.

The endogenous viruses in the avian cells are not completely methylated, nor are the Schmidt-Ruppin RSV-D (SRD) proviruses in the infected cells completely unmethylated. Avian sarcoma proviruses integrated in rat transformed cloned cells are heavily methylated. In these cells, a region in the 3' end of the env gene is unmethylated in all the src-containing proviruses but not in the transformed defective (td) proviruses. A possible role for the hypomethylation of the 3' end of the env region is proposed.

Animals↗
PubMed1986

Effects of long-term administration of buspirone and diazepam on driver steering control.

The effects of buspirone, diazepam, and placebo on tracking control were investigated over a nine-day period, using three groups of subjects, each with eight females and eight males. Subjects were tested using an interactive, computer-based driving simulator on days one, eight, and nine of the treatment period. On day nine, subjects received alcohol with their drug treatment. Measures of steering control were derived from car-driver transfer functions. Tracking performance was also measured. Diazepam was found to adversely affect steering control measures in comparison with placebo. This was true both after doses on the first as well as the eighth day of treatment. Thus, there was no evidence of behavioral tolerance to diazepam. In contrast, buspirone was not found to have any adverse effects on steering control; in fact, some evidence of improved tracking control was found. When alcohol was added to each treatment on the ninth day, differences between the drug treatment groups were less pronounced but in the same direction as on the first and eighth days.

Administration, Oral↗
PubMed1986

Cognitive performance in geriatric subjects after acute treatment with antidepressants.

The effects of amitriptyline, trazodone and placebo on cognitive skills performance were examined in a group of 15 normal volunteers with a minimum age of 60. Each subject was behaviorally tested after single, acute treatments at weekly sessions using a battery of tasks measuring visual search, division of attention, tracking, critical tracking, rate of information processing, and vigilance. Amitriptyline, 50 mg, produced impairment on the vigilance task, the divided attention task and the critical tracking task. In addition, episodes of extended insensitivity to external stimuli similar to short-term sleep occurred. In contrast, trazodone exhibited impairment only on the critical tracking task. This study indicates that trazodone is less likely than amitriptyline to produce impairment of skills performance aspects of cognition.

Aged↗
PubMed1986

A comparison of the effects of trazodone and amitriptyline on skills performance by geriatric subjects.

Fifteen healthy adults, aged 60 years and older, participated in a double-blind, crossover study of trazodone in comparison with amitriptyline and placebo. A battery of laboratory tests was used to measure drug effects on information processing, attention, and visual-motor skills. Amitriptyline 50 mg impaired vigilance and tracking performance and increased drowsiness. Trazodone 100 mg impaired only the most difficult tracking task. This study demonstrates that cognition and performance are less adversely affected in geriatric subjects by trazodone than by amitriptyline beginning 90 minutes after a single-dosage trial.

Administration, Oral↗
PubMed1985

Marihuana and driving.

A review was performed of the marihuana and driving literature, both epidemiological and experimental. It was noted that epidemiological studies face considerable difficulties in obtaining estimates of risks involved for drivers utilizing marihuana due to the rapid decline in blood levels of tetrahydrocannabinol. On the other hand, experimental studies examining the relationship between administered marihuana dose and performance have identified many driving-related areas as exhibiting impairment. Areas impaired include coordination, tracking, perception, vigilance and performance in both driving simulators and on the road. Other behavioral areas of lesser importance for driving also exhibited evidence of impairment by marihuana. Areas for further research are suggested.

Accidents, Traffic↗
PubMed1985

Skills performance at low blood alcohol levels.

The effect of low blood alcohol levels (BALs) on driving skills performance was examined experimentally. Ten moderate drinkers were tested on divided-attention and information processing tasks at BALs of zero, 15, 30, 45 and 60 mg/dl. All response measures showed evidence of impairment beginning at 15 mg/dl and increasing impairment with increasing BALs. Thus there is no evidence that low or very low BALs improve performance on driving-related skills, as has sometimes been suggested.

Adolescent↗
PubMed1984

Attention tasks as skills performance measures of drug effects.

Both empirical epidemiological data on the causes of traffic accidents and conceptual models of skilled human performance stress the central role of perception and cognition. This paper examines the effects of drugs on two major components of cognitive perceptual performance, namely, concentrated attention or vigilance and divided attention. It is demonstrated that these two types of attention tasks are differentially affected by various drugs, so that sometimes one and sometimes another of these tasks is impaired. Various experimental paradigms to investigate these two attention functions are presented. It is demonstrated that attention tasks are frequently highly sensitive to drug effects, suggesting the importance of examining these functions when investigating the effects of drugs on skills performance.

Accidents, Traffic↗