Biomedical subjects

M Donovan

Publications and source records attributed to M Donovan.

At least 19 recordsLinked to original sources

PubMed1996

Gun storage patterns in US homes with children. A pediatric practice-based survey. Pediatric Practice Research Group.

OBJECTIVE: To describe gun storage patterns in gun-owning families with children. DESIGN: Survey of parents attending participating offices. SETTING: Twenty-nine urban, suburban, and rural pediatric practices in Chicago, Ill; New Jersey; Houston, Tex; Utah; Georgia; Iowa; and South Carolina. SUBJECTS: Parents of children attending offices for well- or sick-child care. SELECTION PROCEDURE: Consecutive sample of families seen during the 1-week study period. MEASUREMENTS AND ANALYSES: Logistic regression models were constructed to identify sociodemographic factors associated with keeping guns loaded. RESULTS: Of 5233 surveys, 1682 (32%) indicated ownership of at least one powder firearm. Of the gun-owning families, 61% reported at least one gun unlocked, and 15% reported at least one gun loaded. Rifles were more often stored unlocked (62% rifles vs 52% handguns, P<.001, z=4.60; two-proportion z-test), but handguns were more likely to be kept loaded (3% rifles vs 27% handguns, P<.001). Seven percent of gun-owning families reported at least one gun unlocked and loaded (handguns 12 times more likely than rifles). Only 30% of households reported all guns stored unloaded and locked up. The best-fit logistic regression model for keeping a gun loaded identified four predictor variables: owning a gun for self-protection, work-related gun ownership, owning a handgun, and no men in the home. CONCLUSIONS: Because most gun-owning families store guns loaded, unlocked, or both, anticipatory guidance should address gun storage in all such families. Interventions designed to alter the way work guns are dealt with after work, and to provide safe and effective means of self-protection might affect these storage patterns.

Child↗

PubMed1996

Psychosocial factors in childhood pedestrian injury: a matched case-control study. Kid's'n'Cars Team.

HYPOTHESIS: Psychosocial factors--such as hyperactivity and low family cohesion--contribute to the risk for child pedestrian injury (PI), even after controlling for known demographic risk factors. PARTICIPANTS: Urban PI victims aged 5 to 12 years were recruited from one large, urban pediatric trauma center in a large city. One hundred twenty-eight cases were matched to uninjured children on age, sex, race, location of residence, and parental education. Among matched cases: 70% were male, 41% were black, 33% were Hispanic, and 66% of the mothers had a high school education or less. RESEARCH DESIGN AND MEASUREMENTS: Case-control comparisons on 19 psychosocial variables drawn from interviews and standardized tests, using one-tailed matched-pairs t tests and conditional logistic regression analyses. RESULTS: Cases had higher reported physical quotient [PQ] (P = .01), self-help quotient (P = .04), and family stress (P = .02), and lower family supportiveness (P = .03). Multivariate analyses confirmed that PQ was higher in cases (10-point increase: odds ratio (OR) = 1.32 [90% confidence interval (CI) 1.01-1.76], that stress was higher in cases (1 log increase: OR 2.13, [1.26-3.61]), and that cases had lower family supportiveness (25-point decrease: OR 1.43 [1.25-1.63]). It also identified household crowding as a factor for non-black cases (OR for increase of 0.25 people per room: 2.18, [1.31-3.62]). CONCLUSION: Even when controlling for demographic risk, several family factors and one child factor place children at risk for PI. Clinicians may choose to use these as indicators for injury prevention counseling. Research on family effects may help clarify means to protect children who are demographically at risk for PI.

Accidents, Traffic↗

PubMed1995

Year-to-year variability of cholesterol levels in a pediatric practice.

OBJECTIVES: To study the impact of the variability of blood cholesterol levels, which are known to vary spontaneously. The impact of this variability on screening for hypercholesterolemia according to National Cholesterol Education Program (NCEP) guidelines was reviewed in a private pediatric practice. DESIGN: Retrospective chart review. SETTING: Private pediatric practice. PATIENTS: Children (N = 646) aged 3 to 19 years. INTERVENTION: Cholesterol measurements at a mean interval of 19 months between visits. MAIN OUTCOME MEASURES: Year-to-year change in cholesterol levels according to NCEP guidelines, regression to the mean, age, pubertal status, body mass index, hematocrit, interval between measurements, and season of the year were assessed for their contribution to cholesterol level variability. RESULTS: Cholesterol level varied significantly with both age (P < .001) and pubertal status (P < .01) with children aged 9 to 12 years; prepubertal children had the highest levels. Visit-to-visit consistency of NCEP classification was poorer for younger children than for older children (kappa = 0.21 for 3- to 6-year-olds, 0.39 for 6- to 10-year-olds, and 0.44 for those older than 10 years). Of children with initial total cholesterol levels of 5.17 mmol/L (200 mg/dL) or greater, only 40% continued to have high levels at follow-up. A child with an initial cholesterol value of 5.17 mmol/L (200 mg/dL) showed an average decline of 0.34 mmol/L (13 mg/dL) at follow-up by regression analysis. CONCLUSION: Year-to-year variability in total cholesterol level has a significant impact on the stability of NCEP classification.

Adolescent↗

PubMed1995

Children's and women's ability to fire handguns. The Pediatric Practice Research Group.

OBJECTIVES: To evaluate whether strength differences between children and women might keep children from firing handguns and to determine how many young children can fire available handguns. DESIGN: One- and two-index finger trigger-pull strength was tested using a standard protocol. Data on trigger-pull settings of 64 commercially available handguns were obtained. SETTING AND PARTICIPANTS: Convenience sample of well children and their mothers at four Chicago (Ill)-area pediatric practices for health supervision visits, and of siblings of emergency department patients, during an 8-week period. INTERVENTION: None. MAIN OUTCOME MEASURE: One- and two-index finger trigger-pull strength of mothers and children. RESULTS: Twenty-five percent of 3- to 4-year-olds, 70% of 5- to 6-year-olds, and 90% of 7- to 8-year-olds have a two-finger trigger-pull strength of at least 10 lb, the fifth percentile one-finger trigger-pull strength of adult women. Forty (62.5%) of 64 handguns require trigger-pull strength of less than 5 lb; 19 (30%) of 64 require 5 to 10 lb. CONCLUSIONS: Significant overlap exists in the trigger-pull strength of young children and women, limiting the potential use of increased trigger-pull settings to discourage firearm discharge by children. Young children are strong enough to fire many handguns now in circulation.

Adolescent↗

PubMed1995

Child pedestrian injury taxonomy based on visibility and action.

With data from multidisciplinary investigations of child pedestrian injuries in Chicago, a new and simpler four-category taxonomy is presented based on the process that led to the collision. Two dimensions are recognized: the visibility of the child and/or the vehicle immediately prior to the event and the rapidity of action, either movement or change in direction, of the victim or the vehicle. The taxonomy is neutral with respect to responsibility for the collision and accommodates the findings of other researchers. This classification scheme is tested empirically using objective data elements such as child gender and age and event location. It is further tested using the results of a multidisciplinary causal sequence reconstruction of each injury event, based on such factors as child's psychological character, traffic risks, driver behavior, visibility obstructions, whether the child negotiated part of the street before being struck, and child's activities immediately prior to the injury. The results show that events in the categories in this new taxonomy are distinctly different from each other, and that the structure is useful for identifying and organizing interventions.

Accidents, Traffic↗

PubMed1995

The cellular retinoic acid binding proteins.

The two cellular retinoic acid binding proteins, CRABP I and CRABP II, belong to a family of small cytosolic lipid binding proteins and are highly conserved during evolution. Both proteins are expressed during embryogenesis, particularly in the developing nervous system, craniofacial region and limb bud. CRABP I is also expressed in several adult tissues, however, in contrast, CRABP II expression appears to be limited to the skin. It is likely that these proteins serve as regulators in the transport and metabolism of retinoic acid in the developing embryo and throughout adult life. It has been proposed that CRABP I sequesters retinoic acid in the cytoplasm and prevents nuclear uptake of retinoic acid. A role in catabolism of retinoic acid has also been proposed. Recent gene targeting experiments have shown that neither of the two CRABPs are essential for normal embryonic development or adult life. Examination of CRABP I expression at subcellular resolution reveals a differential cytoplasmic and/or nuclear localization of the protein. A regulated nuclear uptake of CRABP I implies a role for this protein in the intracellular transport of retinoic acid. A protein mediated mechanism which controls the nuclear uptake of retinoic acid may play an important role in the transactivation of the nuclear retinoic acid receptors.

Amino Acid Sequence↗

PubMed1995

Intravenous propofol vs thiamylal-isoflurane for caesarean section, comparative maternal and neonatal effects.

Several studies on propofol (Diprivan) for induction of anaesthesia during caesarean section have demonstrated its safety, however, it safety during maintenance of anaesthesia is not yet fully evaluated. The present study was undertaken to compare the maternal and neonatal effects of propofol or isoflurane in 74 term parturients undergoing primary or repeat caesarean section. Patients were randomly assigned to two groups, propofol group (n = 37) received propofol 1.5-2.5 mg.kg-1 for induction followed by a continuous infusion of propofol of 0.05-0.2 mg.kg-1.min-1. The isoflurane group (n = 37) received thiamylal 3-4mg.kg-1 for induction followed by isoflurane 0.25-0.75% for maintenance. All patients had rapid sequence induction using succinylcholine and endotracheal intubation, 50% N2O and O2 were used in all patients until delivery. After delivery N2O concentration was increased to 67% and intravenous butorphanol (Stadol) was given as needed. Patients in the propofol group had less hypertension after intubation (P < 0.05) and this was also of shorter duration compared to patients in the isoflurane group (5 min vs 10 min respectively). Maternal blood loss as well as intraoperative awareness and recovery time did not differ significantly between the two groups. Neonatal status as ascertained by Apgar scores, cord acid base status and the neurological and adaptive capacity scores (NACS) was equally good in both groups. It is concluded that propofol used for induction and maintenance of anaesthesia is a safe alternative to thiamylal/isoflurane for patients undergoing caesarean section and is associated with less hypertensive response during laryngoscopy and intubation.

Acid-Base Equilibrium↗

PubMed1995

Desflurane: a new volatile anesthetic for cesarean section. Maternal and neonatal effects.

Desflurane, a new volatile anesthetic agent with low blood/gas solubility, has recently been studied in clinical and animal trials but its use in obstetrics has not been adequately evaluated. This prospective study was undertaken to evaluate the maternal and neonatal effects of desflurane in obstetrical patients. Seventy-five healthy parturients undergoing primary or repeat cesarean section were randomly assigned to one of three groups of 25 each, end-tidal 3% desflurane, 6% desflurane or 0.6% enflurane, combined with 50% N2O and O2. All patients had rapid sequence induction of anesthesia with thiopentone sodium followed by succinylcholine for tracheal intubation. After delivery, anesthesia was maintained with reduced concentration of desflurane or enflurane with 67% N2O in O2, supplemented by butorphanol tartrate. Maternal hemodynamic parameters, blood loss and maternal awareness during surgery were monitored. Neonatal outcome was evaluated by Apgar scores, neurological and adaptive capacity scores (NACS), cord blood gas and acid-base status, and time to sustained respiration (TSR). Maternal blood loss did not differ significantly between the three groups and none of the patients developed intraoperative awareness. All three groups responded to psychomotor performance equally fast. Patients in all three groups developed transient hypertension and tachycardia during induction of anesthesia which returned to baseline values in approximately 5 min. Neonatal outcome was equally good in the three groups. More neonates in the 6% desflurane group had TSR > 90 s compared to the 3% desflurane group (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Obstetrical↗

PubMed1995

Flow cytometric analyses of the lymphocyte subsets in peripheral blood of children with untreated active juvenile dermatomyositis.

Juvenile dermatomyositis (JDMS) is a vasculopathy affecting primarily skin and muscle. Although the etiology is unknown, immunopathogenetic mechanisms appear to play a role in both the susceptibility to the disease and its progression. We measured the percentage and absolute numbers of B cells and T-cell subsets in the peripheral blood of untreated JDMS patients with active early disease and compared the results with those obtained from a study of peripheral blood obtained from a heatlhy age-related control group. The absolute number of total lymphocytes in the peripheral blood of the JDMS patients was significantly lower (P < 0.002) than that observed in the healthy control population, with an associated decrease in the absolute number of all T-cell subsets. No concomitant decrease in the absolute number of B lymphocytes was observed in the JDMS patients. In contrast, the percentage of B lymphocytes and the T-helper/T-suppressor cell ratio were significantly higher in the JDMS group than in the control group (P < 0.001 and P < 0.002, respectively). Retrospective analysis of JDMS patients' serum samples obtained within 1 month of the flow cytometric evaluation indicated that 79% of the sera contained an antinuclear antibody and 46% had immunoglobulin G values above age-adjusted reference ranges. The increased percentage of B cells, the increased T-helper/T-suppressor cell ratio, the positive antinuclear antibody results, and the increased concentration of serum immunoglobulin suggest that humoral immune dysregulation may contribute to the pathogenesis of JDMS.

Acute Disease↗

PubMed1995

Maximum and medium security: the interface.

This paper examines transfer delays for patients moving between medium and maximum security hospitals. Delays appear to be getting shorter and Special Hospitals in particular respond very quickly to requests for admission. Recommendations are made for further improvements in transfer procedures. The authors argue that with closer working relationships between clinicians in Special Hospitals and Regional Secure Units, and the new proactive approach to transfers, the system will become increasingly flexible and responsive. Consequent improvements in the quality of care in Special Hospitals are anticipated, making the arguments for closing them, in turn, less convincing.

Adult↗

PubMed1994

Comparison of a lysed whole blood method to purified cell preparations for lymphocyte immunophenotyping: differences between healthy controls and HIV-positive specimens.

Although the majority of clinical laboratories now use a lysed whole blood (LWB) method for routine immunophenotyping, researchers wishing to perform other types of studies with lymphocytes from HIV+ patients may still need to use purified cell preparations, such as peripheral blood mononuclear cells (PBMC). A comparison study of the two methods was performed, using peripheral blood specimens from normal donors and from patients infected with the human immunodeficiency virus (HIV+). Reproducibility studies and several types of holding studies (both before and after specimen processing) were also performed. The results suggest that the two different methods of sample preparation have different effects upon abnormal patient specimens than those observed in healthy controls. Immunophenotyping results derived from the two different methods cannot be considered equivalent for the purposes of quantitating the presence of a particular type of cell.

Antigens, CD↗

PubMed1994

Characterization of the KIN2 gene product in Saccharomyces cerevisiae and comparison between the kinase activities of p145KIN1 and p145KIN2.

We have isolated two yeast genes, KIN1 and KIN2, by their homology to the protein kinase family of viral oncogenes. Previous studies have identified the yeast KIN1 gene product (pp145KIN1) as a 145 kilodalton (kDa) phosphoprotein with serine/threonine-specific protein kinase activity. To identify and biochemically characterize the KIN2 gene product, antibodies were raised against a bacterial beta-galactosidase/KIN2 fusion polypeptide. In vivo, the KIN2 gene product is a 145 kDa phosphoprotein, pp145KIN2. In immune complexes, pp145KIN2 demonstrates serine/threonine protein kinase activity, transferring phosphate from [gamma-32P]ATP to either itself or the exogenously added substrates alpha-casein, acid-denatured enolase, or phosvitin. In vitro, kinase activity is dependent on either Mn2+ or Mg2+ ions. Both enzymes, pp145KIN1 and pp145KIN2, prefer ATP over GTP as their phosphoryl donor. Since a new class of yeast protein kinases has been identified which are serine/tyrosine-specific, we analysed a wide range of substrates to see if any could be phosphorylated by pp145KIN1 or pp145KIN2 on tyrosine residues. Both enzymes phosphorylate alpha-casein, acid-denatured enolase, and phosvitin on serine and threonine residues. Neither enzyme could phosphorylate tyrosine residues even though good substrates for tyrosine-specific kinases such as enolase, angiotensin II, and the synthetic polymer GLU80TYR20 were used. The biochemical analysis of KIN2 kinase activity shows remarkable similarity to that of its most closely related yeast kinase, KIN1. It remains to be seen if these two yeast protein kinases share any functional relationships or substrates in vivo.

Fungal Proteins↗

PubMed1994

KIN1 and KIN2 protein kinases localize to the cytoplasmic face of the yeast plasma membrane.

Two genes, KIN1 and KIN2, were isolated in Saccharomyces cerevisiae by their homology to the protein kinase family of viral oncogenes. In previous studies, we identified the yeast KIN1 gene product (pp145KIN1) and KIN2 gene product (pp145KIN2) as 145 kDa phosphoproteins with serine/threonine protein kinase activity. We have used two approaches to determine the location of these protein kinases in the yeast cell: biochemical fractionation and purification of plasma membrane and cell wall material. Biochemical fractionation techniques revealed that 70-90% of both KIN1 and KIN2 proteins localized to a particulate fraction. This particulate fraction contained three pools of KIN1 and KIN2 proteins. One pool could be released with either sodium chloride or high pH, another released with nonionic detergent, and a third was resistant to either treatment. Thus, both protein-protein and protein-membrane interactions are responsible for the association to the particulate fraction. The presence of these proteins in purified plasma membranes confirms the biochemical fractionation data demonstrating a protein-membrane interaction. Interestingly, a significant fraction of KIN1 and KIN2 proteins are present in purified cell wall preparations. Since protease protection experiments indicate that these proteins are confined to the cytoplasmic face of the plasma membrane and do not protrude into the periplasmic space, any association with the cell wall must be mediated through a protein complex.

Cell Fractionation↗

PubMed1994

Assessment of ventricular relaxation in the developing chick embryo using a monoexponential model.

In this study, the ventricular pressure decline during isovolumic relaxation in early diastole was modeled by regressing pressure and pressure change vs. time to a monoexponential formula: P(t) = P infinity+P0e-t/tau, where P(t) is ventricular pressure at time t, P infinity is the pressure in the fully relaxed ventricle, P0 is the pressure at the end of ventricular ejection, and tau is the ventricular relaxation rate constant. Analysis was performed on 330 ventricular pressure waveforms from 22 chick embryos, stages 17, 23, and 26, during baseline and following cardiac cycle length perturbation. Three computational models were evaluated. Based on analysis of the confidence intervals of estimates of P infinity and analysis of residuals, a least-squares nonlinear regression of pressure vs. time, which allowed estimates of tau and P infinity, best approximated the pressure decline. Isovolumic pressure decline in the embryonic heart is well approximated by a monoexponential model if both P infinity and tau are estimated. Negative values of P infinity during early stages of cardiac morphogenesis support the idea that diastolic suction plays a role in ventricular filling in the developing heart.

Animals↗

PubMed1994