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PubMedDate not supplied

Low-dose cimetidine in the acute treatment of duodenal ulcer. Comparison of a single nocturnal dose regimen with a twice daily regimen.

A 0.5 g daily dose of cimetidine was as effective as a 1 g dose in the acute treatment of duodenal ulcer patients in Hong Kong. The aims of the present study were, first, to determine whether low-dose cimetidine treatment was as effective as standard doses in acute duodenal ulcer treatment of patients in Singapore, and second, to compare a single nocturnal dosage regimen with a twice daily regimen. In this single centre, double-blind, controlled trial, 282 patients with endoscopically proven duodenal ulcer were randomized to receive four weeks' treatment with cimetidine using one of three dosage regimens: (A) 800 mg at night; (B) 400 mg at night; or (C) 400 mg twice daily. Two hundred and forty-seven patients were evaluated. The incidences of healing at four weeks were: (A) 40/80 (50%), (B) 39/88 (44%); and (C) 48/79 (61%); (B vs C: P less than 0.05; A vs C: NS; 95% confidence limits: -5% to 27%; A vs B: NS, 95% confidence limits: -6% to 21%). Of 183 patients who had antral biopsies taken, 176 (96%) had histological gastritis, while 167 (91%) were positive for Helicobacter-like organisms. The occurrence of gastritis or Helicobacter-like organisms had no influence on ulcer healing. A 400 mg dose of cimetidine is therefore suboptimal for the treatment of duodenal ulcer in patients in Singapore. A single nocturnal dosage regimen may be less effective than a twice daily regimen.

Adult↗
PubMed1989

Vitamin A, cigarette smoking, and airway obstruction.

The hypothesis that vitamin A, or foods rich in vitamin A such as milk, protects against the development of airway obstruction was tested in a subsample of data from the 1971-1975 National Health and Nutrition Examination Survey. The relative risk (estimated by relative odds) of having airway obstruction, defined as a FEV1/FVC less than or equal to 65%, was measured for different levels of nutrient and food group intakes after adjustment for age, sex, Quetelet Index, caloric intake, and cigarette smoking. Among the white respondents (never smokers or current smokers) whose recalled diet could be considered as typical of their usual diet, the relative odds of having airway obstruction was inversely related to vitamin A intake (x2 for trend = 7.2, p less than 0.01). In the analysis by food groups, the adjusted relative odds of airway obstruction for meat and poultry were 2.4 (95% confidence limits: 1.0 to 5.8) and for milk 1.6 (95% confidence limits: 1.0 to 2.5). The association of airway obstruction with lack of vitamin A or milk intake was clearer among smokers. These findings suggest that a diet poor in vitamin A increases the risk of airway obstruction, and are consistent with the previously reported association of chronic bronchitis, milk intake, and smoking.

Adult↗
PubMed1992

The long-term clinical outcome of 56 patients with biopsy-proven lupus nephritis followed at a single center.

We retrospectively evaluated the clinical outcome of 45 female and 11 male patients with biopsy-proven lupus nephritis, followed at our hospital between February 1974 and February 1990. In the majority signs of nephritis were present at the time systemic lupus erythematosus was diagnosed (range: -42-156 months) and the median time from onset of nephritis to biopsy was 2 months. The median follow-up from the time of the biopsy was 53.5 months (range: 2-192), the median age at biopsy 25 years and the median serum creatinine level 1.2 mg/dl. Initial renal biopsies had the following histopathological classes according to the World Health Organization criteria (n): I (2); II (10); III (10); IV (28); V (5); VI (1). Over the study period active episodes were treated with high-dose oral prednisone alone or combined with intravenous nitrogen mustard and oral chlorambucil (1974-75), azathioprine (1978-86), cyclophosphamide (1986-90) and/or plasma-exchange (1976-84). These strategies were based on literature data or multicenter studies in which we participated. Eight patients developed end-stage renal disease (ESRD) (median: 47 months post-biopsy; range: 20-120). In these, initial biopsies showed class IV in seven, and class V in one. Confounded risk factors for ESRD were class IV biopsy, male gender and serum creatinine level above 1.4 mg/dl. The calculated proportion without ESRD 5 years post-biopsy was 87% (95% confidence limits: 98-76%), and at 10 years 70% (95% confidence limits: 90-49%). Five patients (11.2%) died; causes of death were cerebrovascular accident (n = 2), cerebral lupus (n = 2) and S. aureus sepsis (n = 1).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2000

Clinical surveillance of a thin bipolar pacing lead.

A total number of 415 co-radial, bipolar pacing leads (189 atrial leads; 226 ventricular leads) were implanted in 228 patients between November 1994 and July 1999. Mean pacing thresholds at the implantation were normal at 0.6 V in the atrium and at 0.4 V in the ventricle with a pulse duration of 0.4-0.5 ms. Lead impedance was relatively low (337-447 ohms for atrial leads; 369-459 ohms for ventricular leads) at the implantation and during the follow-up periods. No definite failure in lead materials was observed in either atrial or ventricular leads (mean follow-up of 19.7 and 19.2 months, respectively: up to 52.9 months for both leads). Predicted clinical surveillance up to 10 years calculated statistically showed that the upper 95% confidence limit was a constant of 100%. The lower 95% confidence limits at 5, 7, and 10 years were estimated to be 98.0%, 97.2%, and 96.0%, respectively. From the present study, the ThinLine lead is reliable for both sensing and pacing thresholds, and has excellent predicted lead longevity. Nevertheless, further observation is required regarding cost performance, such as early replacement of the pacemaker generator, because of the lower pacing lead impedance.

Aged↗
PubMed1985

Lactate determination with the lactate analyser LA 640: a critical study.

Using the new method of sample preparation developed by the manufacturer in 1979, the lactate analyser LA 640 now provides reliable measurements of blood lactic acid from blood micro-samples of 20 microliters within 2 min. Reproducibility is comparable to that obtained by spectrophotometric assay with +/- 0.2 mmol . l-1 for 95% confidence limits. High accuracy was also obtained with 95% linked confidence limits within +/- 0.19 mmol . l-1 and +/- 0.46 mmol . l-1 for blood lactate concentrations of from 2-4 and 7-9 mmol . l-1 respectively. Due to a lactate concentration increase of 0.5 mmol . l-1 . h-1 in whole blood kept at 20 degrees C, the blood must be immediately diluted in the buffer haemolysing solution after withdrawal. This diluted sample can then be stored at room temperature without alteration, provided the concentration in the dilution is lower than 0.8 mmol . l-1. For serial successive measurements, a new sample can be tested before the electrode current reaches its background value.

Blood Chemical Analysis↗
PubMed2003

Evaluation of the surveillance program of Streptococcus agalactiae in Danish dairy herds.

The aim of this study was to evaluate the Danish surveillance program of Streptococcus agalactiae in dairy herds with respect to 1) fluctuation over time of the presence of S. agalactiae in bulk tank milk, 2) sensitivity and specificity of the bacteriological method used, and 3) contamination of bulk tank milk samples with milk from other herds. From June to September 1996, bulk tank milk was sampled from 100 Danish dairy herds seven times, with intervals of 2 wk. The samples were examined for the presence of S. agalactiae by four different methods: 1) by the method approved for the program, 2) after ultrasonic treatment of the milk before examination, 3) after freezing down the milk before examination, and 4) after selective preparation of the milk. Selected strains of S. agalactiae were examined by restriction fragment length polymorphism of the gene encoding rRNA to discriminate between the isolates. Streptococcus agalactiae was found in eight of 96 herds in which S. agalactiae had never previously been found during the surveillance program. Streptococcus agalactiae was not found in all seven sampling rounds in any of the eight herds. Comparing the approved method with supplemental findings by the other methods, the estimated sensitivity was (95% confidence limits): 0.786 (0.628; 0.892) and the estimated specificity (95% confidence limits): 0.995 (0.985; 0.999). Using all four methods on the same sample could increase the sensitivity, but by comparing the methods individually, there was no significant difference between any of them (P > 0.10). In milk samples from three herds, the ribotype of S. agalactiae was the same as in milk from herds sampled just before; therefore, it could not be ruled out that cross-contamination could occur. Taking into account that S. agalactiae in bulk tank milk reflects the presence of S. agalactiae in at least one udder quarter, this investigation gives further reason to assume that S. agalactiae can be seen sporadically in several herds. A surveillance program based on annual bulk tank milk sample examinations will only detect a limited number of S. agalactiae infected herds. If the overall aim is to identify herds where the infection is established, annual bulk tank milk sample examinations combined with the information of number of colonies of S. agalactiae in the sample will be sufficient.

Animals↗
PubMed2004

Monte Carlo Commissioning of Low Energy Electron Radiotherapy Beams using NXEGS Software.

This work is a report on the commissioning of low energy electron beams of a medical linear accelerator for Monte Carlo dose calculation using NXEGS software (NXEGS version 1.0.10.0, NX Medical Software, LLC). A unique feature of NXEGS is automated commissioning, a process whereby a combination of analytic and Monte Carlo methods generates beam models from dosimetric data collected in a water phantom. This study uses NXEGS to commission 6, 9, and 12 MeV electron beams of a Varian Clinac 2100C using three applicators with standard inserts. Central axis depth-dose, primary axis and diagonal beam profiles, and output factors are the measurements necessary for commissioning of the code. We present a comparison of measured dose distributions with the distributions generated by NXEGS, using confidence limits on seven measures of error. We find that confidence limits are typically less than 3% or 3 mm, but increase with increasing source to surface distance (SSD) and depth at or beyond R(50). We also investigate the dependence of NXEGS' performance on the size and composition of data used to commission the program, finding a weak dependence on number of dose profiles in the data set, but finding also that commissioning data need be measured at only two SSDs.

Journal Article↗
PubMed1987

Foodborne Snow Mountain agent gastroenteritis in a school cafeteria.

In 1984, an outbreak of gastroenteritis occurred at a school with 1,860 students in Brooklyn, NY. In a single-stage cluster sample of 375 students, 129 (34%) had illnesses that met our case definition of vomiting or diarrhea. The mean incubation period was 26 hours, and the mean illness duration was 24 hours. All case students had eaten in the cafeteria on at least one day between Nov 13 and 16, compared with 174/214 (81%) noncase students (P = 10(-8), Fisher exact test). Foods implicated were french fries (relative risk 1.7, 95% confidence limits 1.4, 2.0) and hamburgers (relative risk 1.6, 95%, confidence limits 1.2, 2.1). Two cafeteria employees had served those foods while affected by diarrhea. By a recently developed blocking enzyme-linked immunosorbent assay, six of 11 (55%) case students showed fourfold antibody increases between acute- and convalescent-phase serum samples for Snow Mountain agent, a Norwalk-like virus, compared with one of ten (10%) noncase students (P = .04, Fisher exact test). We strongly suspect, but cannot document conclusively, that the Snow Mountain agent was spread to students on a vector of hot foods contaminated by ill food handlers. Implicated foods conferred low relative risks and could only have accounted for 74% of cases of illness. The strong association between cafeteria exposure and illness, therefore, suggests that additional modes of spread occurred.

Antibodies, Viral↗
PubMed1994

The risk of endometrial cancer in diabetic and hypertensive patients: a nationwide record-linkage study in Finland.

The risk of endometrial cancer (EC) in diabetics and hypertensives was studied as part of the planning of a trial of the efficacy of screening for EC. Two nationwide registers, the Finnish Cancer Registry and the Social Insurance Institution's (SII) population register, were linked to obtain 1715 EC patients diagnosed during 1970-1974 with individually matched controls. Data on the right for state-reimbursed medication for diabetes or hypertension prior to the case's cancer diagnosis was obtained from the SII's population register and was used as indicator of the diseases in question. Diabetes was a strong and hypertension a relatively weak risk factor for EC. The relative risk for the association of EC with diabetes was 4.1 (95% confidence limits 2.7 and 6.9) and with hypertension 1.6 (95% confidence limits 1.3 and 2.1). Diabetics and hypertensives are identifiable risk groups for EC in Finland. Diabetics form a suitable target population for a trial of the efficacy of screening for EC.

Adult↗
PubMed1993

Effects of (-)-stepholidine and tetrahydroberberine on high potassium-evoked contraction and calcium influx in rat artery.

The relaxant effects of (-)-stepholidine ((-)-SPD) and tetrahydroberberine (THB) on rat aorta were studied in vitro. (-)-SPD IC50 18.1 (95% confidence limits 11.1-29.5) mumol.L-1 and THB IC50 18.6 (95% confidence limits 9.2-37.9) mumol.L-1 inhibited the contractions caused by KCl (100 mmol.L-1) concentration-dependently. Both (-)-SPD and THB markedly inhibited the 160 mmol.L-1 KCl-stimulated 45Ca influx. The inhibitions by (-)-SPD 10 mumol.L-1 and 100 mumol.L-1 were 18 +/- 13% (P > 0.05) and 47.0 +/- 2.8% (P < 0.01), respectively. The inhibitions by THB 10 mumol.L-1 and 100 mumol.L-1 were 36 +/- 9% (P < 0.01) and 43 +/- 8% (P < 0.05), respectively. The results showed that the effective concentrations of the 2 drugs inhibiting high KCl-induced contraction and 45Ca transmembrane influx in rat thoracic aorta were at a similar level, and that they were nearly 1/100 and 1/10 of those of verapamil respectively, indicating that (-)-SPD and THB had similar calcium channel blocking effect on rat artery, but were weaker than verapamil.

Animals↗
PubMed1993

Evaluating the breast screening programme: the need for surgical audit.

It is to be anticipated that a reduction in population mortality attributable to mammographic screening would be heralded by an increasing proportion of breast cancer cases diagnosed at earlier stages and by an improvement in case fatality. Few cancer registers routinely produce incidence or survival data by stage at diagnosis and thus improvement in these will be the harder to assess. By thorough casenote review and follow up, this study has determined the usual presentation and survival of breast cancer in Northern Ireland in 1986 before the introduction of screening. Overall, 85% of cases were Manchester stage I or II, figures which accord with other British studies. Five-year survival ranged from 77.8% for stage I (95% confidence limits 71.7%, 82.7%) to 35.7% for stage IV (95% confidence limits 13.0%, 59.4%). Forty-three per cent of cases treated in non-teaching hospitals could not be pathologically staged, more than twice the figure for teaching hospitals (Chi-squared = 15.7, df = 1, P < 0.001). Since many tumours not detected by screening will be treated outside teaching centres, this difference will reduce the statistical power to detect the true shift in stage distribution and improvement in survival from screening. Comprehensive surgical audit would help to resolve the inadequacies in existing data collection and improve the ability to evaluate the outcome of the screening programme.

Adult↗
PubMed1995

Prevalence of alcohol problems among adult somatic in-patients in Naples.

The aim of this cross-sectional study was to determine the prevalence of alcohol problems among adult somatic in-patients in urban hospitals of Naples. The patients were screened with a structured questionnaire regarding life style. After discharge, the patient records were examined and the hospital discharge diagnoses were registered. A patient was considered having an alcohol problem if one or more of the following criteria were fulfilled: (1) a Michigan Alcoholism Screening Test score at or above five; (2) a self-reported daily consumption for at least 2 years of at least 60 g of ethanol for males and 36 g for females; (3) an alcohol-related discharge diagnosis. The prevalence of patients with alcohol problems was significantly (P < 0.01) higher among male (43.8%, 95% confidence limits, 37.6-50.2%) than among female patients (14.8%, 95% confidence limits, 9.6-21.4%). There were no significant differences among the different types of somatic departments regarding the prevalence of alcohol problems when gender was considered. Patients with alcohol problems differed significantly from those without alcohol problems regarding a number of variables: the former drank significantly more alcohol, smoked for more years, and had a higher prevalence of alcohol problems in the family. It is concluded that alcohol problems among in-patients are as prevalent in Naples as in other industrialized countries, that it is often not registered among discharge diagnoses, and that the problems are more prevalent in males than in females, irrespective of the type of department.

Adolescent↗
PubMed2005

Recombinant tissue plasminogen activator for minor strokes: the National Institute of Neurological Disorders and Stroke rt-PA Stroke Study experience.

STUDY OBJECTIVE: Acute ischemic stroke patients eligible for tissue plasminogen activator and with less severe neurologic deficits, although still generally benefiting from therapy, may have a different risk-benefit profile than all eligible acute stroke patients. We address whether patients with a minor stroke should receive tissue plasminogen activator, analyze minor stroke syndromes in the National Institute of Neurological Disorders and Stroke (NINDS) rt-PA Stroke Study, and define what constitutes a "minor stroke." METHODS: The NINDS rt-PA Stroke Study included 624 patients with acute ischemic stroke within 180 minutes of symptom onset within a randomized, double-blind, placebo-controlled trial. To explore the relationship among stroke severity, thrombolytic therapy, and stroke outcome, we defined minor strokes (5 specified definitions) based on the standardized data available at treatment decision, including National Institutes of Health Stroke Scale score. We studied prespecified clinical outcomes, including 3-month favorable outcome (global statistic) defined from a set of standardized clinical scales, dichotomized clinical outcome at 3 months (good=modified Rankin Scale < or =2, bad=modified Rankin Scale >2), and risk of symptomatic intracerebral hemorrhage. RESULTS: For each of the 5 definitions of minor stroke, adjusted odds ratios for treatment benefit were consistently 2.0 with the lower 95% confidence limit, ranging from 1.4 to 1.5, and the upper 95% confidence limit, ranging from 2.7 to 2.9. There were less frequent "bad" outcomes (modified Rankin Scale >2) after therapy with tissue plasminogen activator than placebo. Symptomatic intracerebral hemorrhage within 36 hours of treatment had a frequency in the tissue plasminogen activator-treated subjects, ranging from 0% to 4%, depending on minor stroke definition. CONCLUSION: Recognizing the limitations of post hoc subgroup analyses, we could not detect a difference in the beneficial effects of tissue plasminogen activator in patients with minor stroke syndromes compared to the overall treatment effects in the entire cohort. Our data suggest that the risk-benefit ratio for using tissue plasminogen activator in minor-stroke patients favors treatment in eligible patients.

Confidence Intervals↗
PubMed1994

Morphometric analysis of intestinal mucosa. VI--Principles in enumerating intra-epithelial lymphocytes.

The mucosal response by intra-epithelial lymphocytes (IEL) to antigenic challenge is a useful monitor of local immune activity. Conventional counts of IEL (determined as profile ratios of IEL to enterocyte nuclei) are inaccurate, and over-estimate values by a factor of two, both for disease-control mucosae and untreated 'flat' gluten-sensitized mucosae. Two further proofs are advanced in this paper which expose the inaccuracy of conventional profile-density IEL counts. New ranges (log-transformed data) indicate a disease-control mean of 11 IEL per 100 enterocytes (95% confidence limits 5-27) and 29 IEL per 100 enterocytes (95% confidence limits 14-61) for untreated flat gluten-sensitive mucosae. For simplicity, if conventional IEL "counts" are halved, correct values (based on precise morphometric analyses) are easily obtained for comparative and other purposes.

Cell Count↗
PubMed1987

Anderson Fabry disease, a close linkage with highly polymorphic DNA markers DXS17, DXS87 and DXS88.

Anderson Fabry disease is an X-linked lysosomal storage disorder caused by alpha-galactosidase A deficiency. Hemizygous males and some heterozygous females develop renal failure and cardiovascular complications in early adult life. We have investigated six large UK families to assess the possible linkage of five polymorphic DNA probes to the Anderson Fabry locus, previously localised to Xq21-24. No recombination was found between Anderson Fabry disease and DXS87, DXS88 and DXS17, which gave lodmax = 6.4, 6.4 and 5.8 respectively at theta = 0.10, (upper confidence limit 0.10). DXS3 gave lodmax 2.9 at theta = 0.10 (upper confidence limit 0.25). DXYS1 was excluded from linkage. The best fit map (DXYS1/DXS3) theta = 0.192 (DXS17/DXS87/DXS88/Anderson Fabry locus) provided no information about the order of loci in parentheses due to the absence of recombinants. The close linkage of DXS17, DXS87 and DXS88, together with alpha-galactosidase A estimation, can be used for antenatal diagnosis and carrier detection until the application of a gene specific probe has been evaluated.

DNA↗
PubMed1996

Determination of end-tidal sevoflurane concentration for tracheal intubation in children with the rapid method.

PURPOSE: Using the conventional method of determining the end-tidal concentration of inhalational anaesthetic for tracheal intubation, a constant end-tidal anaesthetic concentration is maintained for at least 15 min. As sevoflurane has a low tissue/gas partition coefficient, it seems possible in paediatric patients to determine end-tidal concentrations for tracheal intubation more rapidly by using a high inspired concentration. We determined ED50 and ED95 of sevoflurane for tracheal intubation, the end-tidal concentrations that prevented 50% and 95% of patients from coughing and gross purposeful muscular movements after intubation. METHODS: Twenty-nine, ASA 1, unpremedicated patients, aged two to eight years, were enrolled. Anaesthesia was induced using a mask and 5% sevoflurane, inspired, in oxygen. When end-tidal sevoflurane concentration attained a predetermined value, laryngoscopy and tracheal intubation were performed using an uncuffed tracheal tube without neuromuscular relaxants or adjuvants. Each concentration at which laryngoscopy and tracheal intubation were attempted was randomly predetermined (with 0.5% as a step size). When tracheal intubation was accomplished without gross purposeful muscular movements, it was considered a smooth tracheal intubation. RESULTS: The ED50 end-tidal sevoflurane concentration for tracheal intubation was 3.10% (95% confidence limits: 2.43% and 3.78%), and the ED95 was 4.68% (95% confidence limits: 3.91% and 12.74%). The times to end-tidal sevoflurane concentrations of 3.0% and 4.5% were 149 +/- 15 sec (mean +/- SD) and 213 +/- 23 sec. CONCLUSION: In paediatric patients, this method enabled determination of ED50 and ED95 end-tidal sevoflurane concentrations for tracheal intubation without obtaining a long stabilization period.

Anesthetics, Inhalation↗
PubMedDate not supplied

Local recurrence of rectal cancer: evaluation with F-18 fluorodeoxyglucose PET imaging.

BACKGROUND: Positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG) is a useful technique for detection of malignancy. The purpose of this study was to determine if FDG-PET scanning using visual and quantitative analyses can identify patients with recurrent colorectal tumor following abdominoperineal resection. METHODS: Eighteen patients were evaluated for possible local recurrence of rectal carcinoma following abdominoperineal resection. The clinical presentation included rising carcinoembryonic antigen levels (n = 5), increasing size of a presacral mass on computed tomography or magnetic resonance (n = 13), or local symptoms (n = 3). Axial PET images of the pelvis were obtained following an injection of 10 mCi of FDG prior to biopsy. Quantitative analysis was performed by calculation of a standardized uptake ratio (SUR), and the images were interpreted by two radiologists in consensus. FDG-PET findings were correlated with histological or cytological findings and with the clinical outcome. RESULTS: Recurrent malignancy was confirmed in 13 patients by surgery (n = 8) or percutaneous biopsy (n = 5). Benign lesions were confirmed in five patients by surgery (n = 1), biopsy (n = 3), or clinical follow up (n = 1). Visual analysis of the FDG-PET data had a sensitivity of 92.3% (12/13) for recurrent disease (95% confidence limits; 63.9%, 99.8%) and a specificity of 80% (4/5; 95% confidence limits; 28.3%, 99.4%). SUR values were significantly higher in malignant lesions (range = 2.92-19.74, mean = 6.89) than in benign ones (range = 1.40-3.47, mean = 1.96; p = 0.002). CONCLUSION: FDG-PET is an accurate technique for detection of locally recurrent colorectal carcinoma. Visual analysis is equivalent to quantitative analysis for detection of disease.

Deoxyglucose↗
PubMed1983

Repeat aortic valvotomy in children.

The outcome in 13 children with congenital valvar aortic stenosis who underwent a repeat valvotomy for significant residual obstruction was reviewed. There was no hospital mortality (confidence limits 0% to 32%), while one late death (8%) occurred (confidence limits 1% to 57%) following the repeat procedure. Cardiac catheterization was performed in 10 patients (77%) following the second valvotomy (2 years, 7 months mean follow-up): (1) three children, all infants at initial valvotomy, had a peak systolic ejection gradient less than or equal to 40 mm Hg and only mild, at most, aortic regurgitation after the repeat operation; (2) the other seven had a peak systolic ejection gradient greater than 40 mm Hg or at least moderate aortic regurgitation, of whom two were infants at first valvotomy while the others ranged in age from 1 to 12 years at initial surgery. These results suggest that repeat aortic valvotomy may not significantly improve the hemodynamic status of those who did not require initial valvotomy early in life.

Adolescent↗