Comparison between continuous and intermittent infusion regimens of cimetidine in ulcer patients

The relative effectiveness of intermittent infusions and primed continuous infusions of cimetidine in the maintenance of intragastric pH greater than or equal to 4.0 was evaluated in a double-blind crossover trial in 26 patients who had active or healed gastroduodenal ulcers. During the intermittent phase, each patient received 300 mg cimetidine intravenously every 6 hours. During the continuous infusion phase, each patient was given a continuous infusion of 37.5 mg cimetidine per hour, preceded by a priming dose of 300 mg cimetidine that was given for 15 minutes. Intragastric pH was monitored continuously. During the last 12 hours of the study, the continuous infusion regimen provided 20% more time in which the pH was more [corrected] than 4.0 with 25% less medication than did the intermittent infusion regimen.     

Genetic Tools in the Study of Drug Self-administration

Recent studies have shown that large genetic differences exist in the extent to which orally delivered ethanol will come to serve as a positive reinforcer under operantly defined conditions. In addition, these studies suggest that a significant correlation exists between results from two-bottle choice studies of ethanol drinking and operant self-administration studies of ethanol functioning as a reinforcer. The present paper reports further genetic influences on ethanol self-administration which were found using Long Sleep and Short Sleep mice, bred selectively for high and low duration of loss of the righting reflex in responses to ethanol, respectively. It was possible to establish ethanol as a reinforcer in Long Sleep mice but not in Short Sleep mice. These results indicate that neurosensitivity to ethanol may determine the absolute amount of ethanol consumption but is not highly related to the ability of ethanol to serve as a positive reinforcer. In addition, this paper presents genetic correlations which indicate that (a) ethanol preference and self-administration are highly correlated across genotype; (b) sensitivity to ethanol and self-administration of this drug are not highly genetically correlated; (c) ethanol is not self-administered in operant studies solely for its caloric value; and (d) there exist important genetic determinants of drug reinforced behavior.     

A pilot study of pulmonary rehabilitation in primary care.

Pulmonary rehabilitation is an effective intervention for patients with chronic obstructive pulmonary disease (COPD). It is usually available only through selected hospitals. A pilot study was undertaken to see if pulmonary rehabilitation performed by the primary health care team in one practice was feasible. Fourteen patients were recruited; 13 completed the programme and one year of follow-up. The programme was well received by patients and staff. There were not enough suitable patients among a practice list of 10,500 to justify the running of this programme for a single practice; one primary care group would suffice     

A new immune-competent animal model of mucosally derived squamous cell carcinoma.

OBJECTIVES: To develop an immune-competent animal model for mucosally derived squamous cell carcinoma (SCCA). STUDY DESIGN: Fifteen Fischer 344 rats were inoculated with 1, 2, 5, 10, or 20 x 10(6) FAT7 cells in their flanks. The animals were observed for tumor growth and metastasis. RESULTS: All animals developed tumors that grew exponentially. Pulmonary metastases developed in all animals and 13% developed lymph node metastases. CONCLUSION: The FAT7 flank tumor in Fischer 344 rats is a new animal model that closely resembles the behavior of human mucosal head and neck cancer. SIGNIFICANCE: The existence of an immune-competent, mucosally derived, and reliable animal model of SCCA that somewhat resembles human head and neck SCCA gives the opportunity to perform immune-modulating experiments on head and neck cancer in these animals. EBM rating: B-3.     

Whole-brain 3D perfusion MRI at 3.0 T using CASL with a separate labeling coil.

A variety of continuous and pulsed arterial spin labeling (ASL) perfusion MRI techniques have been demonstrated in recent years. One of the reasons these methods are still not routinely used is the limited extent of the imaging region. Of the ASL methods proposed to date, continuous ASL (CASL) with a separate labeling coil is particularly attractive for whole-brain studies at high fields. This approach can provide an increased signal-to-noise ratio (SNR) in perfusion images because there are no magnetization transfer (MT) effects, and lessen concerns regarding RF power deposition at high field because it uses a local labeling coil. In this work, we demonstrate CASL whole-brain quantitative perfusion imaging at 3.0 T using a combination of strategies: 3D volume acquisition, background tissue signal suppression, and a separate labeling coil. The results show that this approach can be used to acquire perfusion images in all brain regions with good sensitivity. Further, it is shown that the method can be performed safely on humans without exceeding the current RF power deposition limits. The current method can be extended to higher fields, and further improved by the use of multiple receiver coils and parallel imaging techniques to reduce scan time or provide increased resolution.     

Standardization and quantification of radionuclide solid gastric-emptying studies.

The purposes of this investigation were to standardize and validate a simple quantitative method for performing radionuclide solid gastric emptying that can be used for any dual-head gamma-camera and to establish reference values. METHODS: After eating a solid meal (egg sandwich) labeled with a radionuclide, 20 healthy volunteers (9 male, 11 female) underwent a 90-min gastric-emptying study performed with a triple-head gamma-camera. Two sets of 3 simultaneous projections were acquired sequentially for 30 s each: anterior, right posterior oblique (RPO), left posterior oblique (LPO), posterior, left anterior oblique (LAO), and right anterior oblique (RAO), and this sequence was repeated continuously for 90 min. Time-activity curves were generated using a gastric region of interest for each of the views as well as the conjugate-view geometric mean (GM) data for the anterior/posterior, LAO/RPO, and RAO/LPO combinations. Quantitative parameters were determined: percentage gastric emptying (%GE) at 90 min, half-time (min) based on an exponential fit, and clearance rate (%/min) based on a linear fit. Reference values were determined on the basis of a 95% confidence interval of the t distribution. The results were statistically analyzed and compared. RESULTS: The %GE reference values were greater for the anterior/posterior GM (>or=33%) than for the LAO (>or=31%) and anterior (>or=30%) GMs. The 3 %GE GM methods, the 3 exponential-fit GM methods, and the 3 linear-fit GM methods had high correlation coefficients (r >or= 0.874), and with only a single exception, there was no statistical difference among them. The LAO method and LAO/RPO GM mean method correlated strongly (r = 0.900) and had similar mean values (52% vs. 51%) and reference values (29% vs. 30%). All 3 methods of GM quantification also correlated strongly, and there was no significant difference among them. CONCLUSION: We have described and validated a simple method for radionuclide solid gastric emptying that can be used with a dual-head gamma-camera. We recommend the anterior/posterior GM method and have established reference values (>or=33%).     

Pituitary volume in pediatric obsessive-compulsive disorder.

BACKGROUND: Abnormalities in the limbic-hypothalamic-pituitary-adrenal (LHPA) axis have been implicated in the pathogenesis of obsessive-compulsive disorder (OCD). To our knowledge, however, no prior study has measured pituitary gland volume in OCD. METHODS: Volumetric magnetic resonance imaging studies were conducted in 31 psychotropic drug-na?ve children (10 boys, 21 girls) aged 8-17 years and 31 case-matched healthy comparison subjects. RESULTS: Pituitary volume was significantly smaller in patients with OCD as compared with healthy control subjects (11% smaller). Smaller pituitary volume in patients with OCD was associated with increased compulsive but not obsessive symptom severity. Boys with OCD had smaller pituitary gland volumes compared with control boys (20% smaller). No significant differences in pituitary volume were observed between girls with OCD and control girls. Boys with OCD had significantly smaller pituitary volumes than girls with OCD (31% smaller), whereas control boys also had smaller pituitary gland volumes compared with control girls (21% smaller). CONCLUSIONS: These findings provide new evidence of reduced pituitary volume in pediatric OCD that seems to be more prominent in male patients. The observed alterations in pituitary volume are consistent with neuroendocrine studies that have reported abnormalities in the LHPA axis in OCD.     

Reductions in depressed mood and denial coping during cognitive behavioral stress management with hiv-positive gay men treated with haart

Background: Stress management interventions for HIV-positive persons have been designed to enhance coping skills and encourage health-promoting behaviors with the hope of decreasing distress and slowing disease progression.Purpose: We examined the efficacy of a cognitive behavioral stress management (CBSM) intervention in combination with medication adherence training (MAT) in 130 gay and bisexual men living with HIV infection.Methods: Participants were randomized to either a 10-week CBSM+MAT intervention (n = 76) or a MAT-only condition (n = 54). Measures of self-reported adherence, active cognitive coping (i.e., acceptance and positive reinterpretation), avoidant coping (i.e., denial and behavioral disengagement), and depressed mood were examined over the 10-week intervention period.Results: Men in CBSM+MAT reported reductions in depressed mood and denial coping during the 10-week intervention period, but no changes in active cognitive coping or self-reported adherence were observed. Using path analysis, greater reliance on denial coping at baseline was associated with decreased depressed mood at 10 weeks. We also determined that CBSM+MAT may decrease depressed mood by reducing reliance on denial coping over the 10-week intervention period.Conclusions: Although denial may be an effective means of distress reduction in the short term, reliance on this coping strategy may result in a decreased capacity to effectively manage a variety of disease-related stressors in the long term. CBSM+MAT addresses this potentially detrimental pattern by teaching stress reduction skills that may decrease depressed mood via reduced reliance on denial coping. This research was supported by National Institute of Mental Health Grants P01 MH49548 and T32 MH18917.     

Hepatocyte isolation from pig livers after warm ischaemic injury

Abstract Hepatocyte cultures have been used extensively for a wide variety of physiological, pharmacological and experimental studies. The warm ischaemic period before isolation is kept to a minimum to achieve a high yield of cells isolated and a good viability for culture. We have recently introduced a new concept of liver resuscitation after warm ischaemia that is based on a 3-h reperfusion period with an improved perfusate and simultaneous dialysis. In this study, we applied the new technique for hepatocyte isolation from livers subjected to 80 min of complete ischaemia at 37 °C. Cell yield was improved by a resuscitating perfusion from 58% to 73% and viability from 39% to 76%.     

Heart rate changes in chronic insomnia

This study assessed physiological activity in patients with chronic insomnia before sleep, during sleep and in response to acute stress. Twenty-four subjects with chronic insomnia and 25 normal sleepers slept in the laboratory overnight and were given a stressful performance task in the morning. Heart rate was significantly higher in the insomniac group at night. The next morning, heart rate was not different at baseline, but was significantly higher during the performance task in the insomniac group. These results are discussed as supporting the notion that insomniacs have greater physiological responsivity to stress. Further research is needed to determine if altered physiological activity is a cause or consequence of insomnia.