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Biomedical subjects

J L Wright

Publications and source records attributed to J L Wright.

At least 37 records · Page 2Linked to original sources
PubMed2001

Violent injuries among adolescents: declining morbidity and mortality in an urban population.

STUDY OBJECTIVE: Adolescent homicide rates are decreasing nationally for unclear reasons. We explore changes in intentional injury morbidity and mortality within the context of other injuries and specific causes. METHODS: We performed surveillance of hospital, medical examiner, and vital records for nonfatal injury among adolescents age 10 to 19 years living in the District of Columbia from June 15, 1996, to June 15, 1998, and fatal injury from 1989 to 1998. RESULTS: Over the 2-year study period, 15,190 adolescents were seen for injury, resulting in an event-based rate of 148 injuries per 1,000 adolescents per year; 7% required hospitalization, and 0.8% died. Interpersonal intentional injuries accounted for 25% of all injuries, 45% of hospitalizations, and 85% of injury deaths. Assault morbidity decreased with no change noted for unintentional and self-inflicted injury. Firearm injuries, stabs, and assaults with other objects showed the largest decrease, with no decrease in unarmed assaults. Injury mortality peaked in 1993 and has declined since. Firearms caused 72% to 90% of all injury deaths from 1989 to 1998, most the result of homicide. CONCLUSION: There has been a decline in intentional injury rates over the study periods related to decreased weapon injury; data suggest a change in the lethality of fighting methods but no change in unarmed fighting behavior.

Adolescent↗
PubMed2001

Effect of ECE and NEP inhibition on cigarette smoke-induced cell proliferation in the rat lung.

To investigate the role of endothelins in cigarette smoke-induced cell proliferation, we assessed the effect of two dual nonselective neutral endopeptidase (NEP)/endothelin-converting enzyme (ECE) inhibitors, phosphoramidon and CGS 26303, and of a specific NEP inhibitor, CGS 24592, on cell proliferation in the airways and arterial vasculature of the rat lung. Eight groups of rats were exposed to either room air (group 1, control), the smoke of 10 cigarettes (group 2, smoke only) or groups 1 and 2 in addition to a continuous iv infusion of CGS 24592, CGS 26303, or phosphoramidon (10 mg/kg/24 h). Cigarette smoke produced significant cell proliferation in the airways (epithelium and wall) and in the perialveolar ductular vessels (endothelium and wall). CGS 26303 reduced the smoke-induced proliferation in the endothelium and walls of the vessels adjacent to the alveolar ducts, and in the airway walls, but did not affect proliferation in the airway epithelium. CGS 24592 reduced cell proliferation in the airway wall. Phosphoramidon had no effect. These findings indicate that acute cigarette smoke-induced cell proliferation of the rat airways and pulmonary arterial vessels is mediated, at least in part, through release and actions of endothelins. The effectiveness of the more potent inhibitor, CGS 26303, appears to conform to its site of predominant expression.

Administration, Inhalation↗
PubMed2001

Computer-aided Learning (CAL): an effective way to teach the Index of Orthodontic Treatment Need (IOTN)?

OBJECTIVE: To identify if a lecture or access to a computer aided learning (CAL) programme is more effective in teaching undergraduate dental students IOTN. DESIGN: Prospective controlled trial. SETTING: University Dental Hospital of Manchester, 1999 SUBJECTS: Eighty-five 3rd year undergraduate dental students allocated by pseudo-randomisation to two groups. The first group received a lecture and seminar on IOTN, and the second group were given a seminar and access to a purpose written CAL programme. MAIN OUTCOME MEASURE: A standard test was given to the two groups in the form of ten sets of patient records that they had to score with IOTN Dental Health Component (DHC) and Aesthetic Component (AC). RESULTS: There was no difference in mean score for the two groups with AC score (5.02 and 5.03). The CAL group of students performed best for DHC grade (mean score 5.41 compared with 4.24 for lecture group) and this was statistically significant (p < 0.01). CONCLUSION: Undergraduate dental students can learn to use IOTN as well or better when using a CAL programme compared with a lecture.

Computer-Assisted Instruction↗
PubMed2001

The origin of four squirrel monkey cell lines established by karyotype analysis.

The squirrel monkey is a neotropical primate genus which is widely used in biomedical research but includes individual species and subspecies that respond differently to experimental perturbations. GTG-banding patterns of chromosomes 15 and 16, which are distinct among different squirrel monkey species and subspecies, were used to determine the origin of three lung fibroblast cell lines from squirrel monkeys of unknown genetic background (DPSO 114/74, SqMkLu/68, and 7603830) and to confirm the origin of a lymphoblast cell line (GSML) recently established from Guyanese squirrel monkey. DPSO 114/74 cells are from Peruvian squirrel monkey, SqMkLu/68 cells are Bolivian squirrel monkey, and 7603830 cells are from a Peruvian/Bolivian hybrid. Chromosome analysis of GSML cells confirmed that they are from Guyanese squirrel monkey.

Animals↗
PubMed2001

Assessing an educational intervention to improve physician violence screening skills.

OBJECTIVES: Health professionals play an integral role in assessing the risk of violence in their patients. However, there have been few evaluations of violence prevention education programs for health care personnel. The objective of this study was to evaluate the effects of a violence-screening education program on pediatric residents' and medical students' comfort level and skills in the identification and management of violence risks. SETTING: Adolescent clinic of a tertiary care pediatric hospital. PARTICIPANTS: Fifty-six second-year residents and third-year medical students assigned to a 4-week adolescent clinic rotation. DESIGN: Randomized, controlled comparison study conducted over a 1-year period. INTERVENTION: On alternate months, medical students and residents in the intervention group participated in a 3-hour workshop on violence prevention. The workshop included a didactic session with an overview of firearm, media, and sexual violence; a discussion of risk factors for adolescent violence; and training on the approach to the adolescent interview. Participants also discussed violence risks in the community with a panel of teen health educators, engaged in one-on-one role play with the youth educators, and received feedback on their violence screening skills. The control group received the standard ambulatory clinic manual with articles on violence prevention. EVALUATION METHODS: All participants completed prerotation and postrotation questionnaires assessing their self-reported screening practices, as well as perceived importance and confidence in violence screening. Participants also interviewed and examined an adolescent standardized patient (SP) in the clinic. SPs completed evaluations on the content of the residents' and students' screening, their interpersonal skills, and their skill in the identification and management of the violence-related problem. RESULTS: Over 12 months, 30 control and 26 intervention participants were recruited. There were no differences in prerotation questionnaire scores for intervention and control groups in screening practices, perceived importance and confidence in violence screening. Postrotation intervention participants reported more screening compared with controls on violence in school/neighborhood and fighting history. There was also greater perceived importance in asking about access/use of weapons and violence in school/neighborhood. Intervention participants also had improved performance compared with controls on SP evaluations of screening for violence, identification and management of the violence-related scenario, and interpersonal skills. CONCLUSION: A violence prevention education program with teen health educators improved participants' self-reported violence questioning, as well as increased perceived comfort and importance in violence screening. Participants in the program also improved their identification and management of a standardized violence-related scenario presented in an adolescent clinic setting. adolescent violence, physician education, violence risk screening.

Adolescent↗
PubMed2001

The time-factor in orthodontics: what influences the duration of treatments in National Health Service practices?

UNLABELLED: This study aimed to elucidate factors associated with duration of orthodontic treatment. METHODS: Retrospective analysis of a systematic 2% sample of cases completed in National Health Service practices in England and Wales. Records were collected during 1991. Characteristics of practitioners, patients, malocclusions, treatment variables and outcomes were evaluated. Data were submitted to multivariate analysis, with Log10 Time in Treatment as the dependent variable. RESULTS: Data were available for 1506 cases. The (geometric) mean time in treatment was 13 months. A model was found that explained 41% of the variance. Factors found to increase duration were fixed appliances, multiple stages in the treatments, premolar extractions, and correction of antero-posterior buccal occlusion. Age, buccal segment malocclusion, DHC (Dental Health Component of the Index of Orthodontic Treatment Need) grade 5 and orthodontically qualified practitioners were also associated with slightly longer treatments. CONCLUSIONS: Whilst briefer treatments may be attractive to purchasers, providers and recipients, it should be remembered that thorough treatment, and treatment of more complex malocclusions, tends to take longer. Economic pressures on practitioners to produce high turnovers of cases may be counterproductive in the quest for better outcomes.

Adolescent↗
PubMed2001

Old stone face.

Explore the source record for details and available documents.

Humans↗
PubMed2000

Subtype-selective N-methyl-D-aspartate receptor antagonists: synthesis and biological evaluation of 1-(heteroarylalkynyl)-4-benzylpiperidines.

4-[4-(4-Benzylpiperidin-1-yl)but-1-ynyl]phenol (8) and 4-[3-(4-benzylpiperidin-1-yl)prop-1-ynyl]phenol (9) are potent NR1A/2B receptor antagonists (IC(50) values 0.17 and 0.10 microM, respectively). Administered intraperitoneally, they both potentiated the activity of L-DOPA in the unilaterally 6-hydroxydopamine-lesioned (6-OHDA) rat, a model of Parkinson's disease. However, compound 9 was not active orally, likely due to rapid first-pass metabolism of the phenol moiety. The phenol was replaced by several bicyclic heterocyclic systems containing an NH group to function as a H-bond donor in the hope that these would be less likely to undergo rapid metabolism. In general, indoles, indazoles, benzotriazoles, indolones, and isatins gave analogues with weaker NR1A/2B activity than the parent phenols, while benzimidazolones and benzimidazolinones gave equipotent or more potent analogues. The preference for a para arrangement between the H-bond donor and the linking acetylene moiety was confirmed, and a propyne link was preferred over a butyne link. Substitution on the benzyl group or a 4-hydroxyl group on the piperidine had little effect on NR1A/2B potency; however, 4-hydroxypiperidines demonstrated slightly improved selectivity for NR1A/2B receptors versus alpha-1 adrenergic and dopamine D2 receptor affinity. From this study, 5-[3-(4-benzylpiperidin-1-yl)prop-1-ynyl]-1, 3-dihydrobenzoimidazol-2-one (46b) was identified as a very potent, selective NR1A/2B receptor antagonist (IC(50) value 0.0053 microM). After oral administration at 10 and 30 mg/kg, 46b potentiated the effects of L-DOPA in the 6-OHDA-lesioned rat and seemed to have improved oral bioavailability but lower brain penetration compared to phenol 9.

Administration, Oral↗
PubMed2000

Synthesis of N-substituted 4-(4-hydroxyphenyl)piperidines, 4-(4-hydroxybenzyl)piperidines, and (+/-)-3-(4-hydroxyphenyl)pyrrolidines: selective antagonists at the 1A/2B NMDA receptor subtype.

Antagonists at the 1A/2B subtype of the NMDA receptor (NR1A/2B) are typically small molecules that consist of a 4-benzyl- or a 4-phenylpiperidine with an omega-phenylalkyl substituent on the heterocyclic nitrogen. Many of these antagonists, for example ifenprodil (1), incorporate a 4-hydroxy substituent on the omega-phenyl group. In this study, the position of this 4-hydroxy substituent was transferred from the omega-phenyl group to the benzyl or phenyl group located on the 4-position of the piperidine ring. Analogues incorporating pyrrolidine in lieu of piperidine were also prepared. Electrical recordings using cloned receptors expressed in Xenopus oocytes show that high-potency antagonists at the NR1A/2B subtype are obtained employing N-(omega-phenylalkyl)-substituted 4-(4-hydroxyphenyl)piperidine, 4-(4-hydroxybenzyl)piperidine, and (+/-)-3-(4-hydroxyphenyl)pyrrolidine as exemplified by 21 (IC(50) = 0.022 microM), 33 (IC(50) = 0.059 microM), and 40 (IC(50) = 0.017 microM), respectively. These high-potency antagonists are >1000 times more potent at the NR1A/2B subtype than at either the NR1A/2A or NR1A/2C subtypes. The binding affinities of 21 at alpha(1)-adrenergic receptors ([(3)H]prazosin, IC(50) = 0.54 microM) and dopamine D2 receptors ([(3)H]raclopride, IC(50) = 1.2 microM) are reduced by incorporating a hydroxy group onto the 4-position of the piperidine ring and the beta-carbon of the N-alkyl spacer to give (+/-)-27: IC(50) NR1A/2B, 0.026; alpha(1), 14; D2, 105 microM. The high-potency phenolic antagonist 21 and its low-potency O-methylated analogue 18 are both potent anticonvulsants in a mouse maximal electroshock-induced seizure (MES) study (ED(50) (iv) = 0.23 and 0.56 mg/kg, respectively). These data indicate that such compounds penetrate the blood-brain barrier but their MES activity may not be related to NMDA receptor antagonism.

Animals↗
PubMed2000

The pathology of smoking-related lung diseases.

A broad range of non-neoplastic pulmonary lesions is associated with cigarette smoking including airway diseases with airflow limitation, vascular alterations and interstitial lung diseases characterized by diffuse radiographic abnormalities and restricted lung volumes. This article focuses on the pathology of smoking-related emphysema, alterations of large airways, alterations of pulmonary vessels, respiratory bronchiolitis associated interstitial lung disease (RB-ILD), desquamative interstitial pneumonia (DIP), and eosinophilic granuloma (EG).

Arteries↗
PubMed2000

Fluoride-releasing elastomerics--a prospective controlled clinical trial.

A prospective controlled clinical trial was undertaken to evaluate the effectiveness of stannous fluoride-releasing elastomeric modules (Fluor-I-Ties) and chain (Fluor-I-Chain) in the prevention of enamel decalcification during fixed appliance therapy. Forty-nine patients (782 teeth) were included in the experimental group, where the fluoride-releasing elastomerics were used. Forty-five patients (740 teeth) who received non fluoride-releasing elastomerics formed the control group. All patients had their elastomerics replaced at each visit. Enamel decalcification incidence and distribution were recorded using an index by direct clinical observation. In the control group enamel decalcification occurred in 73 per cent of patients and in 26 per cent of all teeth. In the experimental group the corresponding incidence was 63 and 16 per cent, respectively. The overall reduction in score per tooth produced by the fluoride-releasing elastomerics was 49 per cent, a highly significant difference (P < 0.001). A significant difference was seen in all but the occlusal enamel zones. The majority (over 50 per cent) of lesions occurred gingivally. The teeth most severely affected were the maxillary lateral incisors and mandibular second premolars. There was no difference in treatment duration between groups.

Adolescent↗
PubMed2000

Acute cigarette smoke-induced connective tissue breakdown is mediated by neutrophils and prevented by alpha1-antitrypsin.

Recent studies have suggested that macrophage-derived metalloproteases are the critical mediators of cigarette smoke-induced emphysema, in contrast to earlier hypotheses that this process was mediated by neutrophil elastase. To determine whether smoke can acutely induce connective tissue breakdown in the lung and to examine the mediators of this process, we exposed C57-BL/6 mice to whole cigarette smoke and used high-performance liquid chromatography to examine lavage fluid levels of desmosine (DES), a marker of elastin breakdown, and hydroxyproline (HP), a marker of collagen breakdown. Smoke produced a dose-response increase in lavage neutrophils, DES, and HP, but not lavage macrophages (MACs). This effect was evident by 6 h after exposure to two cigarettes. Pretreatment with an antibody against polymorphonuclear leukocytes (PMNs) reduced lavage PMNs to undetectable levels after smoke exposure, did not affect MAC numbers, and prevented increases in lavage DES and HP. Intraperitoneal injection of a commercial human alpha1-antitrypsin (alpha1AT) 24 h before smoke exposure increased serum alpha1AT levels approximately 3-fold and completely abolished smoke-induced connective tissue breakdown as well as the increase in lavage PMNs, again without affecting MAC numbers. We conclude that in this model cigarette smoke can acutely induce connective tissue breakdown and that this effect is mediated by neutrophil-derived serine proteases, most likely neutrophil elastase. Exogenous alpha1AT is protective and appears to inhibit both matrix degradation and PMN influx, suggesting that alpha1AT has anti-inflammatory as well as antiproteolytic effects in this system.

Animals↗
PubMed2000

Sports injuries: An important cause of morbidity in urban youth. District of Columbia Child/Adolescent Injury Research Network.

INTRODUCTION: Sports injuries account for substantial morbidity and medical cost. To direct intervention, a population-based study of the causes and types of sports injuries was undertaken. METHOD: An injury surveillance system was established at all trauma center hospitals that treat residents 10 to 19 years old in the District of Columbia and the Chief Medical Examiner's Office. Medical record abstractions were completed for those seen in an emergency department, admitted to the hospital, or who died from injury June 1996 through June 1998. FINDINGS: Seventeen percent (n = 2563) of all injuries occurred while participating in 1 of 6 sports (baseball/softball, basketball, biking, football, skating, and soccer) resulting in an event-based injury rate of 25.0 per 1000 adolescents or 25.0/1000 population year. Rates were higher in males for all sports. The most common mechanisms were falls (E880-888) and being struck by or against objects (E916-918). Hospitalization was required in 2% of visits and there were no deaths. Of those requiring hospitalization, 51% involved other persons, 12% were equipment-related, and 8% involved poor field/surface conditions. Of all baseball injuries, 55% involved ball or bat impact often of the head. Basketball injuries included several injuries from striking against the basketball pole or rim or being struck by a falling pole or backboard. Biking injuries requiring admission included 2 straddle injuries onto the bike center bar and collision with motor vehicles. Of all football injuries, 48 (7%) involved being struck by an opponent's helmet and 63 (9%) involved inappropriate field conditions including falls on or against concrete, glass, or fixed objects. In soccer there were 4 goal post injuries and a large proportion of intracranial injuries. There were 51 probable or clear assaults during sports and an additional 30 to 41 injuries from baseball bat assaults. CONCLUSIONS: Many sports including noncontact sports involved injuries of the head suggesting the need for improved head protection. Injuries involving collisions with others and assaults point to the need for supervision and enforcement of safety rules. The 16% of sports injury visits and 20% of hospitalizations related to equipment and environmental factors suggest that at least this proportion of injury may be amenable to preventive strategies. Design change may be warranted for prevention of equipment-related injuries. The many injuries involving inappropriate sports settings suggest the need for and use of available and safe locations for sports.

Adolescent↗
PubMed1999

A closer look at General Dental Service orthodontics in England and Wales. II: What determines appliance selection?

AIM: To elucidate factors that influence choice of appliance type in General Dental Service (GDS) orthodontics in England and Wales. METHOD: Records were obtained for 1527 cases, representing a systematic 2 per cent sample of GDS cases completed during 1990-91. Evaluation involved Discriminant Analysis to find the most influential factors in appliance choice. Factors considered included patient and practitioner characteristics, and features of the malocclusion as assessed by Occlusal Indices. RESULTS: Full data were available for 1217 cases. 24 per cent of treatments included use of dual- and 26 per cent single-arch fixed appliances. Appliance choice was predictable in 55 per cent of cases. Older patients, orthodontically qualified practitioners, high Peer Assessment Rating score at start, permanent dentition, lower grades of the Dental Health Component of the Index of Orthodontic Treatment Need at start, and practitioners with high gross earnings from orthodontics, all tended to be associated with more frequent use of fixed appliances. CONCLUSIONS: Possession of a diploma or membership in orthodontics was associated with more frequent use of both dual- and single-arch fixed appliances. Better appliance selection, and thus more effective treatments in the GDS, may result from a greater availability of practitioners with formal postgraduate training in orthodontics.

Discriminant Analysis↗