Born-oppenheimer approximation near level crossing

We consider the Born-Oppenheimer problem near conical intersection in two dimensions. For energies close to the crossing energy we describe the wave function near an isotropic crossing and show that it is related to generalized hypergeometric functions 0F3. This function is to a conical intersection what the Airy function is to a classical turning point. As an application we calculate the anomalous Zeeman shift of vibrational levels near a crossing.

Life expectancy calculations for postcode sectors and their use for monitoring inequalities in the nation's health

OBJECTIVE

To describe how life expectancy calculations can be used to demonstrate differences in mortality between populations of different socioeconomic status at each population census.

DESIGN

Population data were obtained in five-year age-sex and deprivation groups at postcode sector level for the Greater Glasgow Health Board area for the censuses of 1981 and 1991. The numbers of deaths for the same groups were obtained for the three-year periods 1980-82 and 1990-92. Life expectancy tables were derived by applying mortality rates calculated from these data to a synthetic cohort of individuals. Regression analyses were applied to the tables thus derived to examine the relationships between census period, level of deprivation and life expectancy.

RESULTS

Over the period 1980/82 to 1990/92 life expectancy of the age group 0-4 years increased by 2.1 years in males and 2.9 years in females, increases being greater in the more affluent areas. Differences in life expectancy between the geographically defined most deprived and most affluent areas increased from 7.4 to 9.0 years in males and from 5.9 to 6.0 years in females.

CONCLUSION

Life expectancy is increasing in all socioeconomic groups, but particularly in the most affluent. We suggest that life expectancy values should be published routinely for different socioeconomic groupings. Over time these would illustrate more clearly the relationships between health policy and health outcomes, and would demonstrate whether policies are reducing inequalities and generally improving health.

Outcome after ischaemic stroke in childhood

A parental questionnaire was used to investigate the outcome for children who had had ischaemic stroke, who were seen at Great Ormond Street Hospital, London between 1990 and 1996. The results of functional assessments carried out by a physiotherapist and an occupational therapist, and of quantitative evaluations carried out by a neuropsychologist were used for validation where possible. The relationship between clinical and radiological factors and outcome were examined. The children were aged between 3 months and 15 years at the time of stroke (median age 5 years) and the period of follow-up ranged from 3 months to 13 years (median duration 3 years). Of the 90 children for whom data were obtained, 13 (14%) had no residual impairments. Outcome was good in 37 children (40%) and poor in 53 (60%) (defined according to whether impairments interfered with daily life). Agreement, as measured by Cohen's kappa, was good or very good between the parents' responses and the qualitative measures provided by the medical professionals and the therapists, but only fair to moderate for the quantitative measures provided by the neuropsychologists. This may reflect different parental perceptions of the physical and cognitive aspects of outcome. Younger age at time of the stroke was the only significant predictor of adverse outcome.

Search for scalar top and scalar bottom quarks in pp collisions at square root s=1.8 TeV

We have searched for direct pair production of scalar top and scalar bottom quarks in 88 pb-1 of pp collisions at sqrt[s]=1.8 TeV with the CDF detector. We looked for events with a pair of heavy flavor jets and missing energy, consistent with scalar top (bottom) quark decays to a charm (bottom) quark and a neutralino. The numbers of events that pass our selections show no significant deviation from standard model expectations. We compare our results to the next-to-leading order scalar quark production cross sections to exclude regions in scalar quark-neutralino mass parameter space.

Search for a W' boson via the decay mode W'-->munumu in 1.8 TeV pp collisions

We report the results of a search for a W' boson produced in pp collisions at a center-of-mass energy of 1.8 TeV using a 107 pb-1 data sample recorded by the Collider Detector at Fermilab. We consider the decay channel W'-->&munumu and search for anomalous production of high transverse mass munumu lepton pairs. We observe no excess of events above background and set limits on the rate of W' boson production and decay relative to standard model W boson production and decay using a fit of the transverse mass distribution observed. If we assume standard model strength couplings of the W' boson to quark and lepton pairs, we exclude a W' boson with invariant mass less than 660 GeV/c2 at 95% confidence level.

The timing is never right: Mexican views of condom use

Unprotected sex is a critical issue in the Hispanic community, with the incidence of new Hispanic acquired immune deficiency syndrome (AIDS) cases three times that of non-Hispanic Whites. The researchers used focus groups to examine: (a) whether newly immigrated Mexican men and women in the Southeast United States discussed human immunodeficiency virus (HIV)/sexually transmitted disease (STD) prevention with each other, and (b) how condom use was discussed. For the women, communication was safe sex, and for the men, trust was safe sex. Both communication and trust were dependent on timing in the relationship. Participants could not discuss condoms in a new or established relationship because of issues of trust. This study highlights the complexity of HIV/STD prevention and suggests that trust and timing should be considered within the cultural context of condom introduction.

Ethics in the practice of psychiatry in South Africa

OBJECTIVE

To determine attitudes with regard to ethics in the practice of psychiatry in South Africa.

DESIGN

Cross-sectional survey.

METHOD

The study utilised clinical vignettes, with gender and race of the patient as potential modifying variables in diagnosis and management. Open-ended questions pertaining to potential abuses were included.

SETTING AND SUBJECTS

Questionnaires were mailed to all practising psychiatrists in South Africa in 1993 and 1994.

OUTCOME MEASURES

Responses to questionnaire.

RESULTS

A 40% response rate was obtained (N = 73). Patient race and gender did not influence diagnosis or have a marked impact on the prescription of treatment. Pressure from the patient's family on the psychiatrist did alter case management, as did the psychiatrist's age and gender in some instances. Racial discrimination, sexual misconduct and economic abuses were the most frequently cited areas of observed abuse.

CONCLUSION

The development of an ethical framework for the practice of psychiatry in South Africa would appear to be of critical importance.

Outcome of an institutional sexual offender treatment program: a comparison between treated and matched untreated offenders

Data from a sexual offender treatment program operated by the Correctional Service of Canada at the Regional Psychiatric Center (Saskatoon) supported the conclusion that cognitive behavioral treatment can reduce sexual offense recidivism. The study compared 296 treated and 283 untreated offenders followed for a mean of 6 years after their release. An untreated comparison subject was located for each treated offender on three dimensions: (a) age at index offense, (b) date of index offense, and (c) prior criminal history. Data were analyzed using tests of proportion, survival analysis, and analysis of offender Criminal Career Profiles. Over a mean follow-up period of almost 6 years, convictions for new sexual offenses among treated offenders were 14.5% versus 33.2% for untreated offenders. During the follow-up period, 48% of treated offenders remained out of prison compared to 28.3% of untreated offenders. Time series comparisons of treated and comparison samples also showed that treated men reoffended at significantly lower rates after 10 years. A Criminal Career Profile (CCP) was constructed by taking the Age at First Conviction and plotting the offender's successive lengths of time free against time incarcerated. Pre- and posttreatment slopes of the CCP were lower for both groups posttreatment; however, the degree of change was significantly greater for the treated group, indicating a greater reduction in criminal activity among these offenders. Taken together, the results of all three analytic techniques supported the efficacy of appropriate correctional treatment for effective reduction of recidivism.

How useful is uterine artery Doppler flow velocimetry in the prediction of pre-eclampsia, intrauterine growth retardation and perinatal death? An overview

OBJECTIVE

To evaluate the clinical usefulness of Doppler analysis of the uterine artery velocity waveform in the prediction of pre-eclampsia and its associated complications of intrauterine growth retardation and perinatal death.

DESIGN

Quantitative systematic review of observational diagnostic studies using online searching of the MEDLINE database coupled with scanning of the bibliographies of primary and review articles including known unpublished studies.

MATERIAL

Twenty-seven studies involving 12,994 subjects stratified into population subgroups at low and high risk of developing pre-eclampsia and its complications.

OUTCOME MEASURES

The outcome measures studied were: 1. the development of pre-eclampsia; 2. intrauterine growth retardation; and 3. perinatal death. The main meta-analyses were the flow velocity waveform ratio +/- diastolic notch derived by transabdominal Doppler ultrasound as the measurement parameter. The analyses were conducted using likelihood ratio as a measure of diagnostic accuracy. A likelihood ratio of 1 indicates that the test has no predictive value for the outcome. Prediction for the outcome event is considered conclusive with likelihood ratios of > 10 or < 0 x 1 for a positive and negative test result, respectively. Moderate prediction can be achieved with likelihood ratios of 5-10 and 0 x 1-0 x 2 whereas likelihood ratios values of 1-5 and 0 x 2-1 would generate only minimal prediction.

RESULTS

In the low risk population a positive test result, predicted pre-eclampsia with a pooled likelihood ratio of 6 x 4 (95% CI 5 x 7-7 x 1), while a negative test result had a pooled likelihood ratio of 0 x 7 (95% CI 0 x 6-0 x 8). For intrauterine growth retardation the pooled likelihood ratio was 3 x 6 (95% CI 3 x 2-4 x 0) for a positive test result and 0 x 8 (95% CI 0 x 8-0 x 9) for a negative test result. Using perinatal death as outcome measure, the pooled likelihood ratio was 1 x 8 (95% CI 1 x 2-2 x 9) for a positive test result and 0 x 9 (95% CI 0 x 8-1 x 1) for a negative test result. In the high risk population a positive test result predicted pre-eclampsia with a pooled likelihood ratio of 2 x 8 (95% CI 2 x 3-3 x 4), while a negative test had a likelihood ratio of 0 x 8 (95% CI 0 x 7-0 x 9). For intrauterine growth retardation the pooled likelihood ratio was 2 x 7 (95% CI 2 x 1-3 x 4) for a positive test result and 0 x 7 (95% CI 0 x 6-0 x 9) for a negative result. For perinatal death the pooled likelihood ratio was 4 x 0 (95% CI 2 x 4-6 x 6) for a positive test result and 0 x 6 (95% CI 0 x 4-0 x 9) for a negative result.

CONCLUSION

Uterine artery Doppler flow velocity has limited diagnostic accuracy in predicting pre-eclampsia, intrauterine growth retardation and perinatal death.

Suggested curriculum guidelines on complementary and alternative medicine: recommendations of the Society of Teachers of Family Medicine Group on Alternative Medicine

BACKGROUND AND OBJECTIVES

The widespread use of alternative and complementary therapies by the public provides a new challenge to medical education. No standardized curriculum is available for medical educators in this field. Providing an adequate background on these therapies and reliable, useful information to our learners was a task addressed by the Society of Teachers of Family Medicine (STFM) Group on Alternative Medicine over the past 2 years.

METHODS

The group met at conferences and communicated via e-mail to develop a consensus of recommended knowledge, skills, and attitudes in complementary and alternative medicine for incorporation into the family practice residency training curriculum.

CONCLUSION

This article suggests guidelines as developed by this STFM group to assist programs wishing to include formal training in complementary and alternative medicine in residency training.

Genes, chromosomes, and rhabdomyosarcoma

Rhabdomyosarcomas are a heterogeneous group of malignant tumors and are the most common soft-tissue sarcoma of childhood. Rhabdomyosarcomas resemble developing skeletal muscle, notably in their expression of the MRF family of transcription factors and the PAX3 and PAX7 genes. These PAX genes are also involved through specific translocations, t(2;13)(q35;q14) and variant t(1;13)(p36;q14) in the alveolar subtype, which result in PAX3-FKHR and PAX7-FKHR fusion genes, respectively. The fusion genes are thought critically to affect downstream targets of PAX3 and PAX7 or possibly have novel targets. Similar downstream changes may also be involved in embryonal and fusion gene negative cases. Genomic amplification of such genes as MYCN, MDM2, CDK4, and PAX7-FKHR is a feature mainly of the alveolar subtype, while specific chromosomal gains, including chromosomes 2, 8, 12, and 13, are associated with the embryonal subtype. Loss of alleles and imprinting at 11p15.5 and disruption of genes such as IGF2, ATR, PTC, P16, and TP53 have also been implicated in rhabdomyosarcoma development. Whereas there is now a realistic possibility of cure in the majority of cases, there remains a subset that is resistant to multimodality therapy, including high-dose chemotherapy. Characterization of the defining molecular features of tumors that are likely to behave aggressively represents a particular challenge. Current research is leading toward a better understanding of rhabdomyosarcoma tumorigenesis, which may ultimately result in novel therapeutic strategies that increase the overall cure. Genes Chromosomes Cancer 26:275-285, 1999.

Aerobic training involving a minor muscle mass shows greater efficiency than training involving a major muscle mass in chronic heart failure patients

BACKGROUND

Beneficial training outcomes have been reported in sedentary patients with chronic heart failure (CHF) after exercise training. However, data on training effects in previously trained patients, as well as comparisons of different exercise modes, are lacking. The aim of this study is to compare exercise training on a cycle ergometer (major muscle mass) and aerobic knee-extensor training (minor muscle mass) in previously trained patients with CHF.

METHODS AND RESULTS

Twenty-four men and women (age, 63 +/- 10 years [mean +/- SD]) with stable, moderate CHF (left ventricular ejection fraction, 30% +/- 11%) who had completed their first exercise training period more than 1 year ago were allocated to either the exercise or control group. After stratification for sex, age, ejection fraction, and cardiac output response, the training group was further randomized to either cycle ergometer or knee-extensor training for 8 weeks. The control and training patients did not differ at baseline, and the measured variables did not change in the control group during the 8 weeks. Citrate synthase activity in skeletal muscle increased after cycle training (23%; P < .02) and knee-extensor training (45%; P < .008), and blood lactate concentration at submaximal intensities decreased (P < .04) in both groups. However, only after knee-extensor training did the peak oxygen uptake increase (19%; P < .01) and sympathetic nervous system activity, measured as plasma norepinephrine concentration at rest (P < .05) and during exercise (P < .008), decrease. Minnesota Living with Heart Failure questionnaire scores also showed improvement in the health-related quality of life (P < .05) only after knee-extensor training.

CONCLUSION

Physical training is beneficial in previously trained patients with CHF. Aerobic training involving a minor muscle mass shows greater efficiency than training involving a major muscle mass.

Disruption of imprinted genes at chromosome region 11p15.5 in paediatric rhabdomyosarcoma

Rhabdomyosarcomas are characterized by loss of heterozygosity (LOH) at chromosome region 11p15.5, a region known to contain several imprinted genes including insulin-like growth factor 2 (IGF2), H19, and p57(KIP2). We analyzed 48 primary tumour samples and found distinct genetic changes at 11p15.5 in alveolar and embryonal histological subtypes. LOH was a feature of embryonal tumours, but at a lower frequency than previous studies. Loss of imprinting (LOI) of the IGF2 gene was detected in 6 of 13 informative cases, all harbouring PAX3-FKHR or PAX7-FKHR fusion genes characteristic of alveolar histology. In contrast, H19 imprinting was maintained in 14 of 15 informative cases and the case with H19 LOI had maintenance of the IGF2 imprint indicating separate mechanisms controlling imprinting of IGF2 and H19. The adult promoter of IGF2, P1, was used in 5 of 14 tumours and its expression was unrelated to IGF2 imprinting status implying a further mechanism of altered IGF2 regulation. The putative tumour suppressor gene p57(KIP2) was expressed in 15 of 29 tumours and expression was unrelated to allele status. Moreover, in tumours with p57(KIP2) expression, there was no evidence for inactivating mutations, suggesting that p57(KIP2) is not a tumour suppressor in rhabdomyosarcoma.

Coordinated movement of RACK1 with activated betaIIPKC

Protein kinase C (PKC) isozymes move upon activation from one intracellular site to another. PKC-binding proteins, such as receptors for activated C kinase (RACKs), play an important role in regulating the localization and diverse functions of PKC isozymes. RACK1, the receptor for activated betaIIPKC, determines the localization and functional activity of betaIIPKC. However, the mechanism by which RACK1 localizes activated betaIIPKC is not known. Here, we provide evidence that the intracellular localization of RACK1 changes in response to PKC activation. In Chinese hamster ovary cells transfected with the dopamine D2L receptor and in NG108-15 cells, PKC activation by either phorbol ester or a dopamine D2 receptor agonist caused the movement of RACK1. Moreover, PKC activation resulted in the in situ association and movement of RACK1 and betaIIPKC to the same intracellular sites. Time course studies indicate that PKC activation induces the association of the two proteins prior to their co-movement. We further show that association of RACK1 and betaIIPKC is required for the movement of both proteins. Our results suggest that RACK1 is a PKC shuttling protein that moves betaIIPKC from one intracellular site to another.

Intrapartum umbilical artery Doppler velocimetry as a predictor of adverse perinatal outcome: a systematic review

OBJECTIVE

To evaluate the diagnostic prediction of intrapartum umbilical artery Doppler velocimetry for adverse perinatal outcomes using systematic quantitative overview of the available literature.

DESIGN

Online searching of MEDLINE database (January 1966-September 1997), scanning of bibliography of known primary and review articles, review of recent journal issues and that from personal files. Study selection, assessment of study quality and data extraction were all performed in duplicate under masked conditions.

PARTICIPANTS

2700 women (unselected, low, high, and combined low and high obstetric risk populations) included in eight studies selected for meta-analyses.

MAIN OUTCOME MEASURES

Likelihood ratios (LRs) for positive and negative test results were generated for the following outcome measures: Apgar scores < 7 at 1 and 5 minute following delivery, small for gestational age fetus; intrapartum fetal heart rate abnormality, umbilical arterial acidosis at delivery; and caesarean section for fetal distress.

RESULTS

For Apgar score < 7 at 1 minute following delivery, the pooled LR was 2.5 (95% CI 1.7-3.7) for a positive test and 1.0 (95% CI 0.9-1.1) for a negative test result. A positive test predicted an Apgar score < 7 at 5 minute following delivery with a pooled LR of 1.3 (95% CI 0.4-4.1) while a negative test had a pooled LR of 1.0 (95% CI 0.8-1.2). For the prediction of a small for gestational age fetus, the pooled LR was 3.4 (95% CI 2.3-5.1) for a positive test and 0.9 (95% CI 0.8-1.0) for a negative test. The prediction for fetal heart rate abnormality during labour was similarly disappointing: the pooled LR for a positive test result was 1.4 (95% CI 0.9-1.2) whereas a negative test result generated a pooled LR of 0.9 (95% CI 0.9-1.0). With umbilical acidosis at delivery, the pooled LR was 1.6 (95% CI 1.1-2.5) for a positive test and 1.1 (95% CI 1.0-1.2) for a negative test. The LRs for the prediction of caesarean section for fetal distress were 4.1 (95% CI 2.7-6.2) for a positive test result and 0.9 (95% CI 0.8-1.0) for a negative test result.

CONCLUSION

Intrapartum umbilical artery Doppler velocimetry is a poor predictor of adverse perinatal outcomes.

The effect of diclofenac sodium on the initial comfort of RGP contact lenses: a pilot study

BACKGROUND

We conducted a pilot study to assess the effect of 0.1% diclofenac sodium eyedrops on the initial comfort of rigid gas permeable (RGP) contact lenses.

METHODS

A double-masked, placebo-controlled, crossover trial was performed on 20 unadapted subjects. In Phase I, subjects used either 0.1% diclofenac or placebo eyedrops four times per day for 3 days before RGP lenses were dispensed. Contact lenses were inserted on Day 4 and worn for 8 continuous hours. Eyedrops were used twice during the 8-hour period. Ocular symptoms were graded on a visual analog scale at six points during the day. Visual acuity and slitlamp examinations were performed at the same six study points. After a 2-week wash-out period, subjects received the opposite treatment in Phase II, following the same protocol used in Phase I.

RESULTS

The treatment effect was tested using the Mainland-Gart chi-square test. There was no statistically significant treatment effect (chi-square = 0.20, p = 0.653) on patient symptoms. Biomicroscopy findings were analyzed and, likewise, showed no significant treatment effect (chi-square = 2.10, p = 0.15).

CONCLUSIONS

Data from this pilot study showed no statistically significant reduction in symptoms or signs with diclofenac eyedrops.

Naltrexone's effect on cue-elicited craving among alcoholics in treatment

BACKGROUND

Advancing knowledge of biobehavioral effects of interventions can result in improved treatments. Thus, a standardized laboratory cue reactivity assessment has been developed and validated to assess the cognitive and psychophysiological responses to a simulated high-risk situation: alcohol cues. The present study investigates the effects of a pharmacotherapy (naltrexone) on a laboratory-based, cue-elicited urge to drink among abstinent alcoholics in treatment.

METHODS

Alcohol-dependent subjects were randomized to 12 weeks of naltrexone or placebo after completing a partial hospital program. After approximately 1 week on medication, all received cue reactivity assessment.

RESULTS

Significantly fewer patients taking naltrexone reported any urge to drink during alcohol exposure than did those on placebo. Those with any urges reported no decrement in level of the urges. Mean arterial pressure decreased significantly for those on placebo, but not for those on naltrexone, whereas cue-elicited decreases in heart rate were not affected by the medication.

CONCLUSIONS

The results have implications for models of relapse and naltrexone's effects. Cue reactivity methodology has utility for investigating hypothesized mediators of therapeutic effects of pharmacotherapies as well as behavioral treatments.

Beneficial effects of exercise training in heart failure patients with low cardiac output response to exercise - a comparison of two training models

BACKGROUND

Exercise capacity of patients with chronic heart failure (CHF) correlates poorly with estimates of cardiac function. Yet, it has been suggested that only patients without severely impaired cardiac output (CO) benefit from exercise training. Comparisons of different training models have not been made in the same study.

AIMS

To evaluate whether the response to different training models diverges according to the cardiac output response to exercise in patients with chronic heart failure.

METHODS

Sixteen CHF patients (63 +/- 11 years) with an ejection fraction of 30 +/- 11% underwent a baseline cardiopulmonary exercise test, right heart catheterization and leg muscle biopsy. Cardiac output (CO) response to exercise was defined as the ratio between CO increase and the increase in oxygen uptake (CO response index) during exercise. Patients were randomized into two training regimens, differing with regard to active muscle mass, i.e. whole body and one-legged exercise.

RESULTS

Baseline exercise capacity expressed as W kg-1 correlated with the CO response index (r = 0.51, P < 0.05). Exercise capacity on the cycle ergometer increased in both groups but more in the one-legged than in the two-legged training group (P < 0.05). The improvement in exercise capacity did not correlate with base-line exercise capacity. It correlated with CO response index in the one-legged (r = 0.75, P < 0.01) but not in the two-legged training group. CO response index correlated negatively with the pulmonary capillary wedge pressure at peak exercise (r = - 0.60, P < 0.05). The increase in leg muscle citrate synthase activity after training correlated negatively with the baseline CO response index (r = - 0. 50, P < 0.05).

CONCLUSIONS

The improvement of exercise capacity after one-legged training correlates with the CO increase in relation to the O2 uptake before training. In patients with low CO response, individualization of the exercise regimen is needed and the benefits of training a limited muscle mass at a time deserve further study.