Effects of labetalol treatment on the physiological and subjective response to smoked cocaine

Adrenergic receptors mediate some of the physiological and possibly behavioral effects of cocaine. The purpose of this study was to investigate the effect of treatment with a peripherally acting adrenergic blocking drug labetalol on the cardiovascular and subjective response to repeated deliveries of smoked cocaine. In this double-blind, placebo-controlled, crossover study, 12 cocaine users were treated with a single 100 or 200 mg dose of labetalol, or placebo in each of three experimental sessions. Starting 2 h after the medication treatment, subjects received three doses of 0.4 mg/kg smoked cocaine, 30 min apart. Labetalol treatment significantly attenuated the cocaine-induced increases in heart rate and systolic blood pressure. This effect of labetalol on the cardiovascular response did not decrease with repeated cocaine deliveries. The subjective response to smoked cocaine deliveries was not affected by labetalol treatment. These results suggest that labetalol effectively attenuates the systolic blood pressure and heart rate increases induced by repeated doses of smoked cocaine, but does not alter subjective effects.

Negative stress echocardiographic responses in normotensive and hypertensive patients with angina pectoris, positive exercise stress testing, and normal coronary arteriograms

OBJECTIVES

To systematically compare the results of dobutamine stress echocardiography in matched groups of hypertensive and normotensive patients with anginal chest pain and normal coronary arteriograms (CPNA).

SETTING

University hospital.

SUBJECTS

33 patients with exertional anginal chest pain, a positive exercise stress ECG, and a completely normal coronary arteriogram; 17 had a history of systemic hypertension (14 women; mean (SD) age 57 (6) years), and 16 had no hypertensive history (12 women; age 54 (9) years).

METHODS

Ambulatory ECG monitoring, dobutamine stress echocardiography, and thallium-201 single photon emission computed tomography (SPECT) were performed in all subjects.

RESULTS

All patients had normal left ventricular systolic function at rest and none fulfilled the criteria for ventricular hypertrophy. Eight normotensive patients and 10 hypertensive patients had perfusion abnormalities on thallium SPECT (p = 0.61). Dobutamine infusion reproduced anginal pain in seven normotensive and seven hypertensive patients (p = 0.88). ST segment depression was also recorded in eight normotensive patients and seven hypertensive patients (p = 0. 61). No patient in either group developed regional wall motion abnormalities during dobutamine stress echocardiography.

CONCLUSIONS

Neither hypertensive nor normotensive CPNA patients developed regional wall motion abnormalities during dobutamine stress echocardiography, despite the high prevalence of scintigraphic perfusion defects in both groups and the presence of chest pain and ST segment depression. Thus myocardial ischaemia was not present in either group, or else dobutamine stress echocardiography is insensitive to ischaemia caused by microvascular dysfunction.

Comparative gene mapping workshop: progress in agriculturally important animals

Following the successful Comparative Mapping Workshop held at Fraser Island, Australia in 1995, HUGO organized a second workshop of 41 invited participants, held at Toulouse, France on May 3 and 4, 1999. The aim of the conference was to focus on recent developments in genome mapping in a variety of vertebrate species, with particular emphasis on progress in farm animals (cattle, pigs, chickens, sheep, horses, goats, and deer). In addition, representatives from important experimental mammalian and vertebrate organisms (e.g. mice, rats, dogs, fugu, and marsupials) also participated in the meeting. After a rapid overview of developments in the construction and comparison of genome maps in a wide variety of species, discussion focused on how comparative genomics will play a vital role in the genetic dissection of multigenic traits and the characterization of agriculturally important loci in agricultural species. Acceleration of gene discovery with heterologous ESTs (Expressed Sequence Tags) or collections of ESTs was discussed. Recent developments in the construction of cDNA libraries and the efficiency of tools such as whole genome radiation hybrids (RH) and large fragment clone libraries (YACs and in particular BACs) were discussed. Proposed criteria to improve the identification of homologous genes between species and recommendations for nomenclatures were identified. Particular emphasis was placed on how the integration of biological databases could help the scientific community.

Genital tract electrical burns during hysteroscopic endometrial ablation: report of 13 cases in the United States and Canada

We investigated 13 alleged thermal injuries to the genital tract of women undergoing hysteroscopic endometrial ablation. Possible mechanisms proposed to explain these injuries are hot-weighted speculum, povidone-iodine scrub solution, inadequate rinsing of Cidex sterilizing solution, and electrical burns. The history, nature, and distribution, as well as experimental evidence strongly support the hypothesis that these injuries are electrical due to capacitive coupled currents induced onto the sheath of the resectoscope, and/or stray currents generated by arcing or direct coupling from defective electrode insulation to the telescope, electrifying the entire resectoscope.

Adolescents are not adults: developmental considerations in alcohol users

Much of the work in adolescent substance abuse assessment and treatment has been a direct transport from tools and modalities used in adult substance use populations. There was a consensus among symposium participants that developmental issues are important in assessment, evaluation, and treatment of adolescents with substance use disorders. These issues directly impact outcome at all levels. Presentations from the symposium may be helpful for conceptualizing the problems of adolescent substance use as well as formulating strategies for future research. Information from the symposium may be viewed as a springboard for future research and clinical intervention in adolescent substance abuse.

Is there a relationship between serum S-100beta protein and neuropsychologic dysfunction after cardiopulmonary bypass?

OBJECTIVES

Over the past decade, the glial protein S-100beta has been used to detect cerebral injury in a number of clinical settings including cardiac surgery. Previous investigations suggest that S-100beta is capable of identifying patients with cerebral dysfunction after cardiopulmonary bypass. Whether detection of elevated levels S-100beta reflects long-term cognitive impairment remains to be shown. The present study evaluated whether perioperative release of S-100beta after coronary artery operations with cardiopulmonary bypass could predict early or late neuropsychologic impairment.

METHODS

A total of 100 patients undergoing elective coronary bypass without a previous history of neurologic events were prospectively studied. To exclude noncerebral sources of S-100beta, we did not use cardiotomy suction or retransfusion of shed mediastinal blood. Serial perioperative measurements of S-100beta were performed with the use of a new sensitive immunoluminometric assay up to 8 hours after the operation. Patients underwent cognitive testing on a battery of 11 tests before the operation, before discharge from the hospital, and 3 months later.

RESULTS

No significant correlation was found between S-100beta release and neuropsychologic measures either 5 days or 3 months after the operation.

CONCLUSION

Despite using a sensitive immunoluminometric assay of S-100beta, we found no evidence to support the suggestion that early release of S-100beta may reflect long-term neurologic injury capable of producing cognitive impairment.

The ROOT MERISTEMLESS1/CADMIUM SENSITIVE2 gene defines a glutathione-dependent pathway involved in initiation and maintenance of cell division during postembryonic root development

Activation of cell division in the root apical meristem after germination is essential for postembryonic root development. Arabidopsis plants homozygous for a mutation in the ROOT MERISTEMLESS1 (RML1) gene are unable to establish an active postembryonic meristem in the root apex. This mutation abolishes cell division in the root but not in the shoot. We report the molecular cloning of the RML1 gene, which encodes the first enzyme of glutathione (GSH) biosynthesis, gamma-glutamylcysteine synthetase, and which is allelic to CADMIUM SENSITIVE2. The phenotype of the rml1 mutant, which was also evident in the roots of wild-type Arabidopsis and tobacco treated with an inhibitor of GSH biosynthesis, could be relieved by applying GSH to rml1 seedlings. By using a synchronized tobacco cell suspension culture, we showed that the G(1)-to-S phase transition requires an adequate level of GSH. These observations suggest the existence of a GSH-dependent developmental pathway essential for initiation and maintenance of cell division during postembryonic root development.

Effects of improvement in aerobic power on resting insulin and glucose concentrations in children

In this study we determined the influence of improving aerobic power (VO(2max)) on basal plasma levels of insulin and glucose of 11- to 14-year-old children, while accounting for body fat, gender, pubertal status, and leisure-time physical activity (LTPA) levels. Blood samples were obtained from 349 children after an overnight fast and analyzed for plasma insulin and glucose. Height, mass, body mass index (BMI), and sum of skinfolds (Sigma triceps + subscapular sites) were measured. LTPA levels and pubertal status were estimated from questionnaires, and VO(2max) was predicted from a cycle ergometry test. Regardless of gender, insulin levels were significantly correlated (P = 0.0001) to BMI, skinfolds, pubertal stage, and predicted VO(2max), but were not related to LTPA levels. Fasting glucose levels were not correlated to measures of adiposity or exercise (LTPA score, VO(2max)) for females; however, BMI and skinfolds were correlated for males (P < 0.006). The children then took part in an 8-week aerobic exercise program. The 60 children whose VO(2max) improved (>/=3 ml x kg(-1) x min(-1)) had a greater reduction in circulating insulin than the 204 children whose VO(2max) did not increase -16 (41) vs -1 (63) pmol x l(-1); P = 0.028. The greatest change occurred in those children with the highest initial resting insulin levels. Plasma glucose levels were slightly reduced only in those children with the highest insulin levels whose VO(2max) improved (P < 0.0506). The results of this study indicate that in children, adiposity has the most significant influence on fasting insulin levels; however, increasing VO(2max) via exercise can lower insulin levels in those children with initially high levels of the hormone. In addition, LTPA does not appear to be associated with fasting insulin status, unless it is sufficient to increase VO(2max).

RADARx: Recognizing, Assessing, and Documenting Adverse Rx events

BACKGROUND

Adverse events are a leading cause of morbidity and mortality. Adverse Drug Events (ADEs) are frequent, under-reported, costly, and largely preventable. Computerized tools expose effectively ADEs and can reduce their impact.

METHODS

RADARx is a Veterans Administration (VA) VistA-compatible M software program that integrates computerized ADE screening, probability assessment, documentation, and reporting capabilities. Data dictionary mapping tools have enabled RADARx implementation at 3 sites. All RADARx alerts generated at VA Medical Center (VAMC) Nashville from 7/1/99 to 9/30/99 were evaluated.

RESULTS

Total ADEs documented using RADARx numbered 57. RADARx discovered 34 ADEs and 48 'potential' ADEs; 23 ADEs were found using traditional means. Overall, 11% of RADARx alerts were true positives. Pharmacist review of the 8-20 alerts generated daily costs between 10 and 30 minutes.

The ROOT MERISTEMLESS1/CADMIUM SENSITIVE2 gene defines a glutathione-dependent pathway involved in initiation and maintenance of cell division during postembryonic root development

Activation of cell division in the root apical meristem after germination is essential for postembryonic root development. Arabidopsis plants homozygous for a mutation in the ROOT MERISTEMLESS1 (RML1) gene are unable to establish an active postembryonic meristem in the root apex. This mutation abolishes cell division in the root but not in the shoot. We report the molecular cloning of the RML1 gene, which encodes the first enzyme of glutathione (GSH) biosynthesis, gamma-glutamylcysteine synthetase, and which is allelic to CADMIUM SENSITIVE2. The phenotype of the rml1 mutant, which was also evident in the roots of wild-type Arabidopsis and tobacco treated with an inhibitor of GSH biosynthesis, could be relieved by applying GSH to rml1 seedlings. By using a synchronized tobacco cell suspension culture, we showed that the G(1)-to-S phase transition requires an adequate level of GSH. These observations suggest the existence of a GSH-dependent developmental pathway essential for initiation and maintenance of cell division during postembryonic root development.

Nontuberculous mycobacterial otomastoiditis in children: four cases and a literature review

Otomastoiditis due to nontuberculous mycobacteria (NTM) is rare but increasingly being recognised. We present four cases and discuss the clinical presentation, pathogenesis, diagnosis, and treatment, with a review of previous case reports in the literature.

Chronic pyelonephritis in association with neuropathic bladder

Progressive chronic pyelonephritis (CPN) leading to renal failure was, in the past, a mode of death in children with meningomyelocele (MMC). With more sophisticated management modalities, renal failure is now uncommon, but the problem of CPN still remains. In this series of 100 children with MMC, 39% have CPN. It is significantly more common in girls than in boys. There is a strong relationship between CPN and vesico-ureteric reflux (VUR). There is no association with raised bladder pressure. The majority of CPN arises in children under the age of 4 years, but damaged kidneys can continue to deteriorate. Although chronic renal failure is rarely seen in children with MMC, there is a risk that this may merely be postponed into adulthood.

Risk perception in context: the Savannah River Site Stakeholder Study

Environmental managers are increasingly charged with involving the public in the development and modification of policies regarding risks to human health and the environment. Involving the public in environmental decision making first requires a broad understanding of how and why the public perceives various risks. The Savannah River Stakeholder Study was conducted with the purpose of investigating individual, economic, and social characteristics of risk perceptions among those living near the Savannah River Nuclear Weapons Site. A number of factors were found to impact risk perceptions among those living near the site. One's estimated proximity to the site and relative river location surfaced as strong determinants of risk perceptions among SRS residents. Additionally, living in a quality neighborhood and demonstrating a willingness to accept health risks for economic gain strongly abated heightened risk perceptions.

Social class, race/ethnicity, and incidence of breast, cervix, colon, lung, and prostate cancer among Asian, Black, Hispanic, and White residents of the San Francisco Bay Area, 1988-92 (United States)

BACKGROUND

To date only eight US studies have simultaneously examined cancer incidence in relation to social class and race/ethnicity; all but one included only black and white Americans. To address gaps in knowledge we thus investigated socioeconomic gradients in cancer incidence among four mutually exclusive US racial/ethnic groups-- Asian and Pacific Islander, black, Hispanic, and white-- for five major cancer sites: breast, cervix, colon, lung, and prostate cancer.

METHODS

We generated age-adjusted cancer incidence rates stratified by socioeconomic position using: (a) geocoded cancer registry records, (b) census population counts, and (c) 1990 census block-group socioeconomic measures. Cases (n = 70,899) were diagnosed between 1988 and 1992 and lived in seven counties located in California's San Francisco Bay Area.

RESULTS

Incidence rates varied as much if not more by socioeconomic position than by race/ethnicity, and for each site the magnitude - and in some cases direction - of the socioeconomic gradient differed by race/ethnicity and, where applicable, by gender. Breast cancer incidence increased with affluence only among Hispanic women. Incidence of cervical cancer increased with socioeconomic deprivation among all four racial/ethnic groups, with trends strongest among white women. Lung cancer incidence increased with socioeconomic deprivation among all but Hispanics, for whom incidence increased with affluence. Colon and prostate cancer incidence were inconsistently associated with socioeconomic position.

CONCLUSIONS

These complex patterns defy easy generalization and illustrate why US cancer data should be stratified by socioeconomic position, along with race/ethnicity and gender, so as to improve cancer surveillance, research, and control.

Y chromosome microdeletion in a father and his four infertile sons

Microdeletions of Yq are associated with azoospermia and severe oligozoospermia. In general, men with deletions are infertile and therefore deletions are not transmitted to sons unless in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) are performed. We report an unusual family characterized by multiple members with infertility and Yq microdeletion. Complete reproductive history, semen analyses and blood samples were elicited from relevant family members. DNA preparation and quantification were performed using commercial kits. A total of 27 pairs of sequence tagged sites based primer sets specific for the Y microdeletion region loci were used for screening. Southern blots using deleted in azoospermia (DAZ) and ribosomal binding motif (RBM) cDNAs were then analysed for confirmation. The proband, his three brothers and father were all found to be deleted for DAZ but not RBM. At the time of analysis, the proband's father was azoospermic whereas his four sons were either severely oligozoospermic or azoospermic. Unlike their father, the four sons are infertile and have no offspring, except for one of them who achieved a daughter only after IVF/ICSI treatment for infertility. Microdeletions of Yq involving the DAZ gene are associated with a variable phenotypic expression that can include evidently normal fertility.

Accreditation of ambulatory surgery centers

Ambulatory surgery centers are flourishing in the United States. Accreditation of these unique facilities by the Accreditation Association for Ambulatory Health Care reflects a commitment to quality, patient-centered care and to excellence in this specialty area. The accreditation process is complex and lengthy; the benefits, however, outweigh the disadvantages. By successfully completing the accreditation process, a facility demonstrates to the public, its patients, and other health care professionals that it provides exemplary ambulatory surgical care. Successfully accredited facilities also have competitive advantages over nonaccredited surgical centers.

Procedural outcome and clinical results after stent deployment from the radial approach

Multi-Link coronary stents, both 15 and 25 mm, can be used from the radial artery approach with a high degree of efficacy. The complexity of coronary artery stenting is greatly diminished by using the Multi-Link stent delivery system, which eliminates the need for "bare stenting."

Necrosis, apoptosis, cytostasis and DNA damage in human lymphocytes measured simultaneously within the cytokinesis-block micronucleus assay: description of the method and results for hydrogen peroxide

A method is described for the inclusion of apoptotic and necrotic cells in the cell counts obtained in the cytokinesis-block micronucleus (CBMN) assay, which is conventionally used solely for the assessment of chromosome breakage, chromosome loss and frequency of dividing cells. The morphological criteria for the recognition and discrimination between necrotic, apoptotic and viable cells are described. Using this comprehensive method we have evaluated the cytotoxic and genotoxic effects of hydrogen peroxide (0-100 microM) in lymphocytes exposed in RPMI 1640 medium. The results obtained indicated significant (P < 0.05) correlations between hydrogen peroxide concentration and the frequency of micronucleated cells (r = 0.39), necrotic cells (r = 0.73), apoptotic cells (r = -0.26) and binucleated cells (r = -0.55). Almost similar results were obtained using the cytosine arabinoside modification of the CBMN assay, which enables excision-repaired sites to be converted to micronuclei. Some of the above end-points were significantly (P < 0.05) correlated with each other (necrosis and apoptosis, R = -0.39; necrosis and micronucleated cell frequency, R = 0.46; necrosis and binucleated cells, R = -0.78; apoptosis and binucleated cells, R = 0.32). It was therefore necessary to use multiple regression analysis to identify the main event induced by hydrogen peroxide, which was necrosis (beta = 0.57, P = 0.0001) and not micronucleus formation (beta = 0. 15, P = 0.1332). Using an ELISA assay we showed that hydrogen peroxide did not induce 8-hydroxydeoxyguanosine. Our data show that the proposed comprehensive test system may provide a better procedure for classifying potential toxic chemicals and enable discrimination between agents that primarily induce cytotoxic effects as opposed to genotoxic effects. The integration of apoptosis and necrosis into the micronucleus assay may also be of practical use in radiosensitivity studies.

Use of a digital hearing aid with directional microphones in school-aged children

The efficacy of a digital hearing aid with a directional microphone was examined in a school-aged population. Twenty children (9 with a mild-to-moderately-severe hearing loss and 11 with a moderate-to-severe hearing loss) between 7 1/2 and 13 2/3 years of age wore the study hearing aids binaurally for 30 days prior to the evaluation. The testing protocol included speech recognition tests using the CID W-22 word lists presented at 72 dB SPL, 65 dB SPL, and 52 dB SPL (at 0 degrees azimuth) in the presence of a 65 dB SPL party noise (180 degrees azimuth). Subjective rating of hearing aid efficacy in the classroom was examined using the Listening Inventory For Education (LIFE) questionnaire. Parental impression on hearing aid efficacy was also collected at the end of the study. The results showed improved speech recognition in noise with the digital directional hearing aid at all presentation levels. Preference for the digital directional hearing aids over the subjects' own omnidirectional analog hearing aids was also seen on the LIFE questionnaire and parental impression. The degree of hearing loss did not seem to have affected the benefits offered by the digital directional hearing aids. These results were compared to results from other studies on the use of directional microphones in hearing aids.