Biomedical subjects

S M Levenson

Publications and source records attributed to S M Levenson.

At least 19 recordsLinked to original sources

PubMed1995

Housing subsidies and pediatric undernutrition.

OBJECTIVE: To test the hypothesis that receipt of housing subsidies by poor families is associated with improved nutritional status of their children. DESIGN: Cross-sectional study. SETTING: Pediatric emergency department of an urban municipal hospital. PATIENTS: Convenience sample of 203 children younger than 3 years and their families who were being seen during one of twenty-seven 24-hour periods. MAIN OUTCOME MEASURES: Anthropometric indicators (z scores of weight for age, weight-for-height, and height-for-age), and the proportion of children with low growth indicator (weight-for-height below the 10th percentile or height-for-age below the fifth percentile, or both, of the reference population). RESULTS: Multivariate analysis controlling for demographics and program participation showed that receipt of housing assistance contributed significantly to z scores for weight-for-age (P = .03) and weight-for-height (P = .04). The risk of a child's having low growth indicators was 21.6% for children whose families were on the waiting list for housing assistance compared with 3.3% for those whose families received subsidies (adjusted odds ratio = 8.2, 95% confidence interval = 2.2 to 30.4, P = .002) CONCLUSION: Receiving a housing subsidy is associated with increased growth in children from low-income families, an effect that is consistent with a protective effect of housing subsidies against childhood undernutrition.

Child Nutrition Disorders↗

PubMed1995

Assessment of compliance with home cardiorespiratory monitoring in infants at risk of sudden infant death syndrome. Collaborative Home Infant Monitoring Evaluation (CHIME).

OBJECTIVES: Documented monitoring was used to evaluate prospectively (1) the level of compliance among infants in whom cardiorespiratory monitoring was clinically indicated and (2) factors that might influence compliance: diagnosis, socioeconomic status, maternal age and education, and alarms. STUDY DESIGN: Sixty-seven infants (51% female, 49% term) were sequentially enrolled, and monitoring was prescribed for the following indications: siblings of sudden infant death syndrome victims (16%), apnea of prematurity (45%), and apparent life-threatening events or apnea of infancy (39%). Demographic data, alarm and event data, and a summary report of monitor use from the first monitor download were obtained. RESULTS: Maternal age, education, and insurance status did not differ significantly by indication for monitoring. The median number of monitor alarms per 10 hours of use was 0.7 for apnea or bradycardia and 0.6 for loose lead alarms. Monitors were available for use in the home from 2 to 106 days (median, 11 days). Median hours of monitor use per full day in the home was 15.5 hours. Of 67 infants, 58 used the monitor for at least part of every day in the home. The number of hours of monitor use per day did not differ significantly by diagnostic category, chronologic age, alarms, maternal age, education, or insurance type. This study population of infants at increased risk of sudden infant death syndrome had excellent compliance; 75% of the infants were monitored more than 10.5 hours per day, and 25% were monitored more than 21 hours per day. CONCLUSIONS: Documented monitoring provides an objective measure of compliance. These data provide a potential goal for level of compliance with home cardiorespiratory monitoring.

Analysis of Variance↗

PubMed1994

Contrasting effects of identical nutrients given parenterally or enterally after 70% hepatectomy.

Based on clinical observations, we hypothesized that prolonged parenteral nutrition (in contrast to enteral nutrition) is detrimental after major hepatic resection. Male Sprague-Dawley rats (300 to 380 g) anesthetized with intraperitoneal sodium pentobarbital had 70% hepatic resection and jugular vein and gastrostomy catheterizations using aseptic techniques and were divided randomly into three groups: (1) total parenteral nutrition (TPN) (nutrients via central vein), (2) total enteral nutrition (TEN) (identical nutrients via gastrostomy), and (3) standard oral feeding (SOF) (chow and water ad libitum). Unused catheters were plugged. In the first set of experiments (n = 42), nutrient intake was formulated to approximate the nutritional intake of normal rats, 216 kcal/kg/d. Infusate was 15% glucose, 4.5% amino acids, electrolytes, trace minerals, vitamins, and 20% fat emulsion given half-strength the first day, three-fourths strength the second day, and full strength thereafter. On postoperative day 7, surviving rats were killed. Mortality prior to day 7 was very high (68%) in the TPN group and low in the TEN (9%) and SOF (9%) groups (p < 0.005). Among survivors, the serum albumin level was lowest (p < 0.002) and serum bilirubin level (p < 0.025) and wet weight of regenerated liver (p < 0.002) highest in the TPN group. However, the livers in TPN rats appeared pale and were found to be abnormal histologically with markedly diminished glycogen and amphophylic hepatocyte cytoplasm, and their spleens were enlarged (by a factor of two). The high mortality of TPN rats was seen whether the fat emulsion was given as a bolus daily, continuously as part of the infusate, or not included as part of the TPN regimen. In the next series (n = 70), nutrient concentrations, volumes, and rates of infusion were varied. There was a high correlation between caloric (r2 = 0.831, p < 0.0006), glucose (r2 = 0.598, p < 0.02), and amino acid (r2 = 0.619, p < 0.03) intakes and mortality in the TPN group: at 140 kcal/kg/d, none died; at 178 kcal/kg/d, 50% to 62% died; and at 230 kcal/kg/d, 80% died. No TEN rat died. In conclusion, 70% hepatectomized rats fed enterally with nutrients approximating the intake of normal rats do well and survive. In sharp contrast, mortality is very high when identical nutrients are infused parenterally. By reducing the levels of nutrients given parenterally, survival improves significantly.

Animals↗

PubMed1994

Wound healing after harvesting of the internal thoracic and the superior and inferior epigastric arteries.

Wound healing of sternal incisions and midline or paramedian abdominal incisions was studied at 2 weeks postoperatively in three groups of dogs. Group 1, 10 dogs, had harvesting of bilateral internal thoracic arteries, superior epigastric arteries, and inferior epigastric arteries. Group 2, 5 dogs, had removal of the same arteries, but the superior and inferior epigastric arteries were harvested through paramedian rather than midline incisions. Group 3, 5 dogs, served as control and had median sternotomies and midline abdominal incisions only. All wounds healed without complication. Wound breaking strength of the skin of the chest incisions was significantly greater (p < 0.05) in the control group (group 3) (52.6 lb) compared with groups 1 (38.0 lb) and 2 (34.8 lb). Wound breaking strength of the skin of the abdominal incisions was significantly greater (p < 0.05) in group 2 (50.4 lb) when paramedian incisions were made compared with group 1 (35.1 lb). Hydroxyproline content was similar for all groups and all incisions. We conclude that abdominal wound breaking strength is significantly greater when paramedian incisions are performed to harvest the inferior epigastric arteries. Harvesting bilateral internal thoracic, superior epigastric, and inferior epigastric arteries may lower sternal wound breaking strength.

Abdomen↗

PubMed1992

The impact of a physician's warning on recovery after alcoholism treatment.

OBJECTIVE: To study whether alcoholic workers had seen physicians during the year they were identified by their company, whether they recalled physicians' warnings about drinking, and whether such warnings affected outcomes 2 years later. DESIGN: Workers were interviewed at intake and 2 years later: subgroups who did and did not see physicians and who did and did not recall warnings were compared. SETTING: A company-union employee assistance program. PARTICIPANTS: Two hundred problem drinkers, newly identified on the job, predominantly male, blue-collar workers. OUTCOMES: Drinking, drunkenness, average daily alcohol consumption, and impairment score. RESULTS: Among the 200 participants, 74% saw physicians in the index year; only 22% recalled warnings. Recall of a warning was associated with liver disease, continued drinking while ill, supervisors' job warnings, older age, and marijuana use. Two years later, those warned were more likely to be abstaining, and sober, and were less impaired. CONCLUSIONS: Recalling a physician's warning at intake into alcoholism treatment was associated with better prognosis 2 years later. However, among this group of employees whose drinking was serious enough to be identified on the job, fewer than a quarter recalled physicians' warnings, even though more than three quarters had seen physicians in the year preceding intake.

Adult↗

PubMed1991

A randomized trial of treatment options for alcohol-abusing workers.

BACKGROUND: Employee-assistance programs sponsored by companies or labor unions identify workers who abuse alcohol and refer them for care, often to inpatient rehabilitation programs. Yet the effectiveness of inpatient treatment, as compared with a variety of less intensive alternatives, has repeatedly been called into question. In this study, anchored in the work site, we compared the effectiveness of mandatory in-hospital treatment with that of required attendance at the meetings of a self-help group and a choice of treatment options. METHODS: We randomly assigned a series of 227 workers newly identified as abusing alcohol to one of three rehabilitation regimens: compulsory inpatient treatment, compulsory attendance at Alcoholics Anonymous (AA) meetings, and a choice of options. Inpatient backup was provided if needed. The groups were compared in terms of 12 job-performance variables and 12 measures of drinking and drug use during a two-year follow-up period. RESULTS: All three groups improved, and no significant differences were found among the groups in job-related outcome variables. On seven measures of drinking and drug use, however, we found significant differences at several follow-up assessments. The hospital group fared best and that assigned to AA the least well; those allowed to choose a program had intermediate outcomes. Additional inpatient treatment was required significantly more often (P less than 0.0001) by the AA group (63 percent) and the choice group (38 percent) than by subjects assigned to initial treatment in the hospital (23 percent). The differences among the groups were especially pronounced for workers who had used cocaine within six months before study entry. The estimated costs of inpatient treatment for the AA and choice groups averaged only 10 percent less than the costs for the hospital group because of their higher rates of additional treatment. CONCLUSIONS: Even for employed problem drinkers who are not abusing drugs and who have no serious medical problems, an initial referral to AA alone or a choice of programs, although less costly than inpatient care, involves more risk than compulsory inpatient treatment and should be accompanied by close monitoring for signs of incipient relapse.

Adult↗

PubMed1991

Associations between alcohol and cocaine use in a sample of problem-drinking employees.

Increases in cocaine use have created a new and challenging cohort of problem drinkers with dual or multiple addictions. As part of a randomized trial comparing alternative alcoholism treatments at a 10,000-employee industrial plant, we interviewed 224 new alcoholic clients of an employee assistance program (EAP); 40% used cocaine during the 6 months just prior to EAP intake. Compared to employees reporting no recent cocaine use, the cocaine users were younger, less often married and reported heavier drinking and more alcohol-related problems, on the job and off. Even after controlling for demographic and occupational factors, and drinking indicators, cocaine users reported more binges (being drunk 24 hours or more), more blackouts (marginally significant, p = .06), more absenteeism and more warnings about unacceptable job performance. Alcoholic EAP clients who use cocaine appear to engage in riskier drinking and to have more trouble on the job than do those who report no cocaine use, and this seems to be a difference specifically attributable to their use of cocaine.

Adult↗

PubMed1990

Zone II flexor tendon repair: effects of vitamins A, E, beta-carotene.

Ninety-six adult Leghorn chickens each had the flexor profundus tendon in each middle toe sharply divided in Zone II with immediate repair (pentobarbital, ketamine anesthesia). Animals were then randomly assigned to receive unsupplemented standard chick chow or the chow supplemented with vitamin A (150,000 IU/kg chow), Vitamin E (1000 IU/kg chow), or beta-carotene (90 mg/kg chow). Eight animals from each of the four groups were examined at 7, 30, or 45 days post repair. After sacrifice, in situ composite wound breaking strength was measured in the amputated toe by constant speed tensiometry. Vitamin A-supplemented animals demonstrated breaking strength more than double that of control at each postoperative test day, while those animals receiving supplemental Vitamin E had breaking strength less than half that of control at Day 7 and Day 45. These results are statistically significant. Tensiometry curves differed markedly at all time points among the groups: Vitamin A curves being broader, higher, and having more spikes. These differences in the tensiometry curves, both qualitative and quantitative, may be due to differences in intrinsic tendon healing or to differences in adhesion formation or a combination of both. beta-Carotene supplementation had modest effect. We conclude that supplemental dietary vitamin A increases the breaking strength of composite tendon wounds and that supplemental dietary vitamin E decreases it.

Animals↗

PubMed1990

Supplemental vitamin A prevents the tumor-induced defect in wound healing.

To test our hypothesis that supplemental vitamin A would mitigate the impaired healing that occurs in tumor-bearing animals, six groups of C3H mice, eight per group, eating a standard commercial mouse chow ad libitum that supports normal growth, reproduction, and longevity were innoculated with 200,000 C3HBA cells. When tumors measured approximately 6 mm in diameter, the mice were anesthesized and wounded (dorsal skin incisions and subcutaneous polyvinyl alcohol sponges). Twenty-four hours later, two groups (one continued on the chow and the other started on the chow supplemented with 150,000 IU vitamin A/kg chow) underwent local tumor irradiation; two groups, one ingesting the chow, the other the vitamin A supplemented chow, were started on cyclophosphamide therapy; two groups, one ingesting the chow, the other the vitamin A supplemented chow, received neither local tumor irradiation nor cyclophosphamide therapy. An additional two groups ingesting the chow, one group neither innoculated with tumor nor wounded, the other wounded by not innoculated, served as controls. Wound breaking strength and sponge reparative collagen accumulation (assessed by hydroxyproline proline measurement) were used as indicators of wound healing. The mice were killed 12 days after wounding. Tumor presence decreased wound breaking strength and sponge hydroxyproline content; these effects were largely negated by supplemental vitamin A. Local tumor irradiation diminished the adverse effect of tumor on sponge reparative collagen content but to a lesser extent than the supplemental vitamin A. Supplemental vitamin A added to the irradiation effect on healing but irradiation did not add to the vitamin A effect. Cyclophosphamide, a systemic radiomimetic anti-tumor agent, did not alter the impaired wound healing of the tumor-bearing mice. Supplemental vitamin A mitigated the impaired wound healing in the cyclophosphamide-treated tumor-bearing mice. Supplemental vitamin A also moderated the effects of wounding, tumor, and tumor therapies (local irradiation and cyclophosphamide) on the increase in adrenal size, leukopenia, thrombocytopenia, and thymic involution (except the last was not moderated in the cyclophosphamide-treated tumor-bearing rats). The splenic enlargement in the untreated tumor-bearing wounded rats and in those treated with cyclophosphamide was lessened by supplemental vitamin A. We hypothesize that these anti-stress effects of vitamin A underlie, in part, its action in mitigating the impaired wound healing of tumor-bearing mice, including those treated by local irradiation or cyclophosphamide. These findings have implications for the care of patients with malignant tumors.

Animals↗

PubMed1989

Effects of maternal marijuana and cocaine use on fetal growth.

To investigate the effects on infants of the use of marijuana and cocaine during pregnancy and to compare the importance of urine assays with that of interviews in ascertaining drug use, we prospectively studied 1226 mothers, recruited from a general prenatal clinic, and their infants. On the basis of either interviews or urine assays conducted prenatally or post partum, 27 percent of the subjects had used marijuana during pregnancy and 18 percent had used cocaine. When only positive urine assays were considered, the corresponding values were 16 percent and 9 percent, respectively. When potentially confounding variables were controlled for in the analysis, the infants whose mothers had positive urine assays for marijuana, as compared with the infants whose mothers were negative according to both interviews and urine assays, had a 79-g decrease in birth weight (P = 0.04) and a 0.5-cm decrement in length (P = 0.02). Women who had positive assays for cocaine, as compared with nonusers, had infants with a 93-g decrease in birth weight (P = 0.07), a 0.7-cm decrement in length (P = 0.01), and a 0.43-cm-smaller head circumference (P = 0.01). To compare our findings with those of other investigators who did not use urine assays, we repeated the analyses, considering only self-reported use of marijuana (23 percent) and cocaine (13 percent). There were no significant associations between such use as determined by interviews alone and any of the measures of outcome. We conclude that the use of marijuana or cocaine during pregnancy is associated with impaired fetal growth and that measuring a biologic marker of such use is important to demonstrate the association.

Adolescent↗

PubMed1989

Impaired liver regeneration in the analbuminemic rat.

Albumin has been implicated as both an inhibitor and a stimulator of liver regeneration. We examined the rate of liver regeneration following partial hepatectomy in rats which are genetically analbuminemic. Adult male analbuminemic and Sprague-Dawley control rats underwent either a 70% partial hepatectomy or a sham operation. Twenty-four hours postoperatively, rats were injected iv with tritiated thymidine and the liver remnants were resected 1 hr later. Liver weight, protein and DNA contents, and the rate of tritiated thymidine incorporation into DNA were determined. The rate of DNA synthesis in control sham-operated rats was greater (P less than 0.05) than that of analbuminemic rats. Following partial hepatectomy, there was a statistically significant (P less than 0.01) increase in DNA synthesis in control rats; no significant increase was noted in the analbuminemic rats. No significant differences in liver remnant weight or protein and DNA contents were noted between control and analbuminemic sham-operated or partially hepatectomized rats. Our data suggest that albumin plays a role in the regulation of DNA synthesis in both the resting and the regenerating liver and it may be essential in maintaining a normal rate of liver regeneration.

Albumins↗

PubMed1988

Repeal of the Massachusetts seat belt law.

In November 1986, the Massachusetts mandatory seat belt use law repealed in a referendum by a 53 per cent to 47 per cent vote. In an anonymous random digit telephone survey of 1,046 adults in Massachusetts in summer 1986, while the law was in effect, 61 per cent of respondents had said they would vote in favor of the law. A post-repeal follow-up of 80 per cent of these persons revealed initial supporters and opponents of the law were equally likely to vote, but 15 per cent of the summer supporters switched their opinions and voted for repeal, compared to only 4 per cent of summer opponents who switched. In addition, a separate survey of 167 households that had refused to answer the summer survey indicated that survey nonrespondents were more likely to vote against the law than for it. Those opposing the law saw it as an infringement on personal liberty and believed it was not effective in reducing injury and death.

Choice Behavior↗

PubMed1988

Cocaine use during pregnancy: prevalence and correlates.

Cocaine use during pregnancy was assessed by interviews and urine assays obtained prenatally and immediately postpartum from 679 urban women enrolled in prenatal care. Of these, 17% were found to have used cocaine at least once during pregnancy. Eight percent had urine assays positive for cocaine metabolites using the enzyme-mediated immunoassay technique with a cut-off of 300 ng/mL of benzoylecgonine. Of the cocaine users, 24% denied use at the time of the interview and were identified solely by urine assay. Cocaine users were significantly (P less than .01) less likely than nonusers to be married, Hispanic, or black born outside of the United States and were less well nourished. Users reported significantly (P less than .01) more sexually transmitted diseases, prior low birth weight infants, spontaneous and elective abortions, and greater use of alcohol, cigarettes, marijuana, opiates, and other illicit drugs during pregnancy. Because cocaine use is correlated with many potential risk factors, large sample sizes and multivariate statistical techniques are needed to determine whether cocaine use during pregnancy poses an independent risk for adverse neonatal outcomes.

Boston↗

PubMed1987

Supplemental dietary tyrosine in sepsis and acute hemorrhagic shock.

Previous studies showed that dopamine and norepinephrine levels in rat brain are reduced following stress and that rats fed supplemental tyrosine do not exhibit these reductions. We hypothesized that dietary supplementation with tyrosine would enhance resistance to acute hemorrhagic shock and sepsis by increasing substrate (tyrosine) availability for catecholamine synthesis. Rats were fed either a standard rat chow (6.8 g of tyrosine per kilogram of chow), which supports normal growth, fertility, and longevity, or the same chow supplemented with 10 g of tyrosine per kilogram of chow. Seven days later, the rats underwent cecal ligation and perforation while under intraperitoneal pentobarbital anesthesia. There was a significant increase in survival in the tyrosine-supplemented group. Similarly, in another experiment, tyrosine-supplemented rats were able to tolerate acute fulminant hemorrhagic shock better than were nonsupplemented control animals.

Acute Disease↗

PubMed1987

Effect of supplemental vitamin A on colon anastomotic healing in rats given preoperative irradiation.

We studied the effect of dietary supplementation with vitamin A on the healing of colon anastomoses in irradiated bowel. Rats were divided into two groups. Those in the first group were fed a standard chow diet and those in the second group were fed the same diet supplemented with 150 IU vitamin A/g of chow. The rats were maintained on their respective diets throughout the experiment. After 7 days, half the rats in each group underwent abdominal irradiation (200 rads). Seven days later, all of the rats underwent distal colon division and anastomosis under pentobarbital anesthesia. All rats were killed 7 days postoperatively, the colons excised, and bursting strength and hydroxyproline determinations performed on both the anastomotic segment and a normal proximal segment of adjacent colon. There was a significant decrease in the bursting strength at the colon anastomosis (p less than 0.02) and in the collagen content (p less than 0.02) after preoperative irradiation. This effect was mitigated by dietary vitamin A supplementation.

Animals↗

PubMed1987

Effect of dietary supplementation with vitamin A on arterial healing in rats.

The effect of dietary supplementation with vitamin A on the healing of rat aortas was studied. Rats were divided into two groups: rats fed a standard chow and rats fed the chow supplemented with 150 IU vitamin A palmitate/g diet. Seven rats from each group were fed with the above diets for 7 days, killed with ether, and the abdominal aorta excised and assayed for hydroxyproline content and collagenase activity. Ten rats from each group were fed for 7 days on the above diets and then underwent a longitudinal aortotomy which was sutured with prolene sutures under pentobarbital anesthesia. The rats were maintained on their respective diets for 7 days and then killed with ether, their abdominal aorta was excised and both the segment with the arteriotomy and the adjacent distal normal segment were analyzed for hydroxyproline content and collagenase activity. Seven rats from each group were fed with the above diets and then underwent transverse division of the abdominal aorta and reanastomosis using nylon sutures under pentobarbital anesthesia. Rats were maintained on their respective diets throughout the postoperative period. Seven days later, all rats were killed with ether and the bursting strength of the aortic anastomoses was measured. The results showed that vitamin A supplementation in non-operated animals had no significant effect on aortic hydroxyproline content or collagenase activity. In rats undergoing longitudinal aortotomy and suture, there was a significant increase in hydroxyproline content both at the healing arteriotomy and at the adjacent non-wounded aorta in the vitamin A-supplemented group. There was also a significant increase in bursting strength of the healing aortic anastomosis in the vitamin A-supplemented rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1987

Wound healing in normal and analbuminemic (NAR) rats.

It has been suggested by several investigators that hypoalbuminemia results in impaired wound healing. In most studies, however, hypoalbuminemia is a manifestation of malnutrition or underlying liver disease. In this study, we examined the effect of isolated hypoalbuminemia on wound healing. Analbuminemic (NAR) rats which are Sprague-Dawley mutants with trace levels of plasma albumin due to a defect in albumin synthesis were studied. Adult NAR and Sprague-Dawley rats (n = 10 each) underwent a 7 cm dorsal skin incision and implantation of a polyvinyl alcohol sponge subcutaneously under pentobarbital anesthesia. Seven days postoperatively all rats were killed with ether, the wounds were excised, and breaking strength was measured. Sponge hydroxyproline content was determined colorimetrically. There were no significant differences in wound breaking strength (fresh or formalin fixed) or sponge collagen content between the Sprague-Dawley and analbuminemic rats. We conclude that isolated hypoalbuminemia has no detrimental effect on would healing in rats.

Animals↗

PubMed1986

Replacement of liver function in rats by transplantation of microcarrier-attached hepatocytes.

Isolated hepatocytes, harvested from normal rat livers by portal vein collagenase perfusion, can be attached to collagen-coated dextran microcarriers and transplanted by intraperitoneal injection into rats. Survival and function of the transplanted hepatocytes have been demonstrated in mutant rats lacking bilirubin-uridine diphosphate glucuronosyltransferase activity (Gunn strain) and rats with inherited lack of plasma albumin (Nagase analbuminemia rat strain). This simple technique promises to be useful in the treatment of acute liver failure in humans.

Animals↗