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PubMed1993

Anatomical variation of the insertion of scalenus anterior in adult human subjects: implications for clinical practice.

The frequency of an abnormally anterior insertion of scalenus anterior to the scalene tubercle on the superior aspect of the 1st rib was examined as a possible contributory factor to venous compression syndromes and to difficulties in cannulation of the subclavian vein. The insertion of scalenus anterior was exposed bilaterally in 21 adult cadavers and its position determined. The position of the scalene tubercle was also determined in a sample of 50 dried 1st ribs. The results were normalised for height. Three of the cadavers had position values that were above or at the upper point of the 95% confidence limits for the sample, indicating an abnormally anterior insertion. Two dried 1st ribs had values just below the lower 95% confidence limits, implying an abnormally posterior position. In the 3 cadavers with an abnormally anterior position, the subclavian artery and vein followed an abnormally anterior and inferior course with respect to the clavicle, and in 1 the subclavian vein was stenosed bilaterally at the costoclavicular angle. An abnormally anterior insertion of scalenus anterior may be a cause of venous compression syndromes in the root of the neck and give rise to difficulties when undertaking cannulation of the subclavian vein.

Abnormalities, Multiple↗

PubMed1996

Is maternal obesity a risk factor for anencephaly and spina bifida?

To determine whether the risk of having an infant with anencephaly or spina bifida is greater among obese women than among average-weight women, we compared 307 Atlanta-area women who gave birth to a liveborn or stillborn infant with anencephaly or spina bifida (case group) with 2,755 Atlanta-area women who gave birth to an infant without birth defects (control group). The infants of control women were randomly selected from birth certificates and frequency-matched to the case group by race, birth hospital, and birth period from 1968 through 1980. After adjusting for maternal age, education, smoking status, alcohol use, chronic illness, and vitamin use, we found that, compared with average-weight women, obese women (pregravid body mass index greater than 29) had almost twice the risk of having an infant with spina bifida or anencephaly (odds ratio = 1.9; 95% confidence limits = 1.1, 3.4). A woman's risk increased with her body mass index: adjusted odds ratios ranged from 0.6 (95% confidence limits = 0.3, 2.1) for very underweight women to 1.9 for obese women.

Adult↗

PubMedDate not supplied

The importance of genetic counseling before amniocentesis.

OBJECTIVE: To determine the adequacy of genetic risk assessment among primary care providers and to evaluate the efficacy of genetic counseling before "routine" genetic amniocentesis. STUDY DESIGN: A retrospective cohort study was undertaken. Charts of 275 consecutive patients referred for genetic counseling and amniocentesis on the basis of advanced maternal age (AMA) were compared with charts of 103 consecutive patients referred for an abnormal maternal serum alpha-fetoprotein (MSAFP) finding. Pedigree information obtained during counseling of these patients was compared with the family histories charted by the referring physician. RESULTS: In 35.6% of pedigrees evaluated, a significant genetic risk was discovered during genetic consultation that had not been noted by the referring physician. Furthermore, 9.8% of AMA patients and 10.7% of patients with abnormal MSAFP results underwent additional genetic testing or screening on the basis of genetic counseling. Additional genetic testing of 0.8% of amniotic fluid specimens was done on the basis of the genetic risk assessment elicited during counseling. Although a significant difference in increased genetic risk was observed between the AMA and abnormal MSAFP groups (AMA 30.8% positive, MSAFP 48.5% positive; relative risk 0.81, confidence limit 0.70 to 0.93), no significant difference was observed between the two groups with regard to patient interventions (relative risk 0.97, confidence limit 0.79 to 1.21) or amniotic fluid testing (p = 0.57, not significant). CONCLUSIONS: The data support the importance of genetic counseling before amniocentesis. Furthermore, the findings support the relevancy and usefulness of genetic counseling in more accurately ascertaining genetic risk and in maximizing the benefits of genetic evaluation of patients seemingly at low risk for other genetic diseases.

Adult↗

PubMed1992

Confidence intervals in medical research.

The utility of confidence intervals in a wide variety of situations in the medical field is re-emphasized, with examples drawn from controlled clinical trials, disease control programmes, vaccine trials and laboratory studies. It is shown that the confidence interval approach is more informative than a mere test of statistical significance, and should therefore be employed as an useful adjuvant. Since proportions are widely quoted in medical literature and as the determination of the exact confidence limits for a binomial proportion is iterative and time-consuming, an assessment is made of 15 published methods which provide approximate confidence limits; the 'Square root transformation' method is recommended since it is accurate and the computation of limits is relatively easy. In the case of a difference between two proportions, the usual method may be employed if sample sizes exceed 75; for smaller sample sizes (even for sizes of 5), the Jeffreys-Perks method is very satisfactory and is therefore recommended.

Confidence Intervals↗

PubMed1995

Evaluation of the protective efficacy of a serotype 1 bovine-human rotavirus reassortant vaccine in infants.

The objective of this study was to evaluate the efficacy of a live, attenuated bovine (strain WC3) x human (strain WI79, serotype G1) rotavirus reassortant (WI79-9) virus vaccine for prevention of symptomatic rotavirus gastroenteritis in infants. The study was a prospective, randomized, double-blind, placebo-controlled trial, conducted over a single rotavirus season in 325 infants who were 2 to 8 months old at enrollment. Subjects were randomized to receive either placebo or WI79-9 virus vaccine at 10(7.3) plaque-forming units in three oral doses each separated by 2 months. Subjects were followed for 7 days after each dose for occurrence of adverse events and during the subsequent winter for development of rotavirus gastroenteritis. Administration of WI79-9 virus vaccine was well-tolerated, and the rates of low grade fever after each dose were no higher in vaccine recipients (8 to 21%) than in placebo recipients (14 to 19%). The protective efficacy of the WI79-9 vaccine during a subsequent epidemic of predominantly serotype G1 rotavirus was 87.0% (95% confidence limits, 62.6 to 95.5%) against relatively severe rotavirus gastroenteritis (rotavirus gastroenteritis with a clinical severity score of > 8) and was 64.1% (95% confidence limits 35.9 to 79.9%) against all symptomatic rotavirus episodes. The WI79-9 vaccine was safe and effective in prevention of homotypic human rotavirus infection in infants. Further studies of reassortant vaccines based on the bovine WC3 rotavirus should be performed.

Confidence Intervals↗

PubMed1999

Efficacy of once-daily versus twice-daily administration of budesonide by Turbuhaler(R) in children with stable asthma.

We evaluated the efficacy of once-daily versus twice-daily treatment with budesonide, delivered by a Turbuhaler(R), in the management of children with stable asthma in a randomized, double-blind, parallel-group study involving 206 children (age 5-15 years). After a 2-week run-in period during which the children were maintained on their usual dose of budesonide (200 microg or 400 microg/day), patients were randomized to receive the same daily dose in either two daily administrations (morning and evening) or as a single dose in the morning over a period of 12 weeks. The primary efficacy variable was morning peak expiratory flow (PEF). The mean morning PEF during the run-in phase was 271 L/min in patients randomized to once-daily treatment and 264 L/min in those randomized to twice-daily treatment. The mean change from baseline to the last 2 weeks of the treatment period in the two groups was -0.3 L/min (95% confidence limits -6.6 to +6.0) and 2.5 L/min (-4.3 to +9.3). The estimated difference between the groups was -2.8 L/min, with 90% confidence limits of -10.4 + 4.5; these were close to the limits regarded as indicative of equivalence (-10 to +10), and hence the difference was not regarded as clinically relevant. Similarly, there were no significant differences between the groups in regard to secondary efficacy measures such as spirometric tests and symptom scores. Both treatments were well tolerated. We conclude that once-daily administration of budesonide by Turbuhaler(R) is as effective as twice-daily treatment in the management of stable asthma in children treated with inhaled steroids at doses of 200-400 microg/day.

Administration, Inhalation↗

PubMed1983

Late onset hypothyroidism after subtotal thyroidectomy for hyperthyroidism: implications for long term follow-up.

A follow-up register has been used in Aberdeen and Dundee to record early and late onset hypothyroidism occurring in a large population of post-thyroidectomy patients treated for hyperthyroidism. In one centre, in a total of 1170 patients, the prevalence of postoperative hypothyroidism, at the time of entry to the register, was 41 per cent. Of these early cases of hypothyroidism 93 per cent occurred within 18 months of operation. Results are presented from a 12-year prospective study of patients treated in two centres, who were euthyroid when entered on the follow-up register. In one centre, based on 683 patients, the 10-year incidence of late onset hypothyroidism estimated by actuarial methods was 7.4 per cent (95 per cent confidence limits, 3.8-11.1); in the other centre with 156 patients the 5-year incidence was 10.8 per cent (95 per cent confidence limits, 3-18.6). The minimum predicted annual incidence is 1 per cent. Large thyroid remnants do not protect some patients against early or late postoperative hypothyroidism but do lead to an increased risk of recurrent hyperthyroidism. Hypothyroidism after subtotal thyroidectomy for hyperthyroidism shows a bimodal pattern and this study emphasizes the need to maintain life-long follow-up.

Follow-Up Studies↗

PubMed1990

Comparison of one dose versus three doses of prophylactic antibiotics, and the influence of blood transfusion, on infectious complications in acute and elective colorectal surgery.

In a randomized prospective controlled trial involving 311 patients undergoing acute or elective colorectal surgery, the efficacy and safety of two different single dose and one triple dose regimen of antibiotic prophylaxis, as well as the influence of blood transfusion on postoperative infectious complications, were studied. Postoperative infectious complications occurred in a total of 59 patients (19.0 per cent). There were no major differences between the three treatment groups. Thirty-four patients (10.9 per cent) developed abdominal wound infection, 17 patients (5.5 per cent) intra-abdominal abscess and 16 patients (5.1 per cent) anastomotic leakage. Of 202 patients (65.0 per cent) requiring blood transfusion during hospitalization 57 (28.2 per cent; 95 per cent confidence limits of 23-36 per cent) developed infectious complications, whereas two non-transfused patients (1.8 per cent; 95 per cent confidence limits of 0.2 to 6 per cent; P less than 0.001) developed infectious complications. It is concluded that one single dose of antibiotic prophylaxis in acute and elective colorectal surgery is as protective as a triple dose regimen. The development of infectious complications despite antibiotic prophylaxis is strongly related to blood transfusion.

Adolescent↗

PubMed1995

Toombak dipping and cancer of the oral cavity in the Sudan: a case-control study.

To investigate the possible causal association between squamous-cell carcinomas of the oral cavity and use of toombak, we retrospectively compared the history of use of this substance in 375 patients with squamous-cell carcinomas of the lip, buccal cavity and floor of mouth, and 271 patients with squamous carcinomas of the tongue, palate and maxillary sinus, with 204 patients exhibiting non-squamous oral and non-oral malignant neoplasms and 2,820 individuals who had no malignancy, selected from the general population. The study revealed that the high prevalence of oral cancer in the Sudan is largely due to chronic use of toombak. The adjusted ORs associated with toombak dipping for the first case group, cancer of the lip, buccal cavity and floor of mouth in comparison with the hospital and population control groups, were 7.3 and 3.9 (95% confidence limits, 4.3-12.4 and 2.9-5.3) respectively and among long-term users the adjusted ORs were 11.0 and 4.3 (95% confidence limits, 4.8-25.1 and 2.9-6.3) respectively. The elevated risk found when investigating intra-oral cancers of sites in direct contact with toombak quid compared to those with little or no contact, confirms the hypothesis that direct contact with tissues is an important factor in tobacco carcinogenesis in the mouth. The increased risk associated with the use of toombak is of particular concern in view of its wide consumption in the Sudan.

Adolescent↗

PubMed1986

[Analysis of decay curves with biphasic kinetics].

Medication of trout and carps with chloramphenicol and sulfadimidine results in tissue residues which best fit by a biexponential decay curve. The analysis of residues does not reveal any systematic deviations of the data from the model. On the basis of this model half lives for the fast and slow drug elimination phases can be estimated. For the assessment of withdrawal times it is necessary to compute confidence limits for the decay curves. A withdrawal time may be defined by the intersection of recommended maximal concentrations with the upper confidence limit. This analysis does not include any metabolites. This model is also suited for monitoring purposes. It is recommended to apply the procedure to all chemicals exhibiting biexponential decay kinetics.

Animals↗

PubMed1988

Does family history of breast cancer improve survival among patients with breast cancer?

Overall cancer mortality to December 1985 among 291 patients whose breast cancer was diagnosed between 1971 and 1974 and who were interviewed shortly after diagnosis was 39.9% (116 deaths). In this study population a positive maternal family history was strongly associated with breast cancer: The odds ratio for patients versus controls of having a mother with breast cancer was 3.32 (95% confidence limits 1.64 and 6.72); the odds ratio of having a mother, sister, or maternal aunt with breast cancer was 1.92 (95% confidence limits 1.27 and 2.91). However, family history was not associated with stage at diagnosis, which is the most important survival factor (53.6% of patients with a family history and 51.7% without were at a local stage at diagnosis). Survival was better, although not significantly so, among women with maternal relatives with breast cancer. The relative risk of dying of cancer, adjusted for confounding factors, was 1.40 for women without versus with a family history; the difference in survival was not statistically significant.

Adult↗

PubMed1998

Dissociation of impairment between spatial memory, and motor function and emotional behavior in aged rats.

We investigated changes in learning and memory in aged rats, in relation to motor function and emotional behavior. Male Kbl Wistar aged rats (108-weeks-old) were divided into two groups, memory impaired and non-impaired, based on performance during six training trials in the Morris water maze task. Aged rats with a goal latency longer than the mean plus the 99% confidence limit of young rats, were regarded as memory impaired, whereas those with a goal latency within the range of the 99% confidence limit of the mean of young rats, were considered as memory non-impaired. Although the performance of the memory impaired aged rats in the standard test of the Morris water maze improved after six re-training trials to the level of the non-impaired aged rats and young rats, working memory impairment was evident. There were no differences in motor function and emotional behavior between the impaired and non-impaired aged rats. These results suggest that deficits of learning and memory in memory impaired aged rats can be dissociated from changes in motor function and emotional behavior.

Aging↗

PubMed1990

Phase II trial of UFT in advanced colorectal and gastric cancer.

A phase II trial of continuous oral therapy with UFT, a combination of uracil and the 5-fluorouracil analogue 1-(2-tetrahydrofuryl)-5-fluorouracil (Futraful, Ftorafur), was conducted in 40 patients with advanced colorectal cancer and 18 patients with advanced gastric cancer. Six partial responses were seen in the 36 evaluable patients with colorectal cancer (response rate 16.6%; 95% confidence limits 6.4-32.8%), and one partial response was seen in the 16 evaluable patients with gastric cancer (response rate 6%; 95% confidence limits 0.27-30.2%). The overall toxicity of the treatment was low, and all patients were treated as outpatients. The results suggest that oral UFT has comparable activity to standard regimes of 5-fluorouracil, and because of the convenience of oral administration is a useful therapy in the management of patients with advanced colorectal cancer.

Adult↗

PubMed2002

From CHART to CHARTWEL in non-small cell lung cancer: clinical radiobiological modelling of the expected change in outcome.

CHART (Continuous Hyperfractionated Accelerated Radiotherapy) has been shown to improve the tumour control probability and survival relative to conventional radiotherapy in patients with inoperable non-small cell lung cancer (NSCLC). CHARTWEL (CHART Weekend-less) is a further development of this schedule escalating the physical dose to 60 Gy while maintaining the low dose per fraction of 1.5 Gy. In this schedule, three fractions, with a minimum interval of 6 h between fractions, are delivered 5 days per week. This extends overall treatment time from the 12 days of CHART to 18 days. Radiobiological modelling is used to estimate the expected tumour control and normal tissue morbidity after CHARTWEL relative to CHART. The estimations are based on the outcome of the CHART trial and published values for dose-fractionation and dose-response parameters for human tissues and tumours. Two new estimates of quantitative radiobiological parameters for early normal-tissue morbidity after chest irradiation are reported here. For radiation pneumonitis, the dose recovered per day is estimated at 0.44 Gy/day with 95% confidence limits 0.07 Gy/day and 0.80 Gy/day. For oesophagitis, the normalized dose-response gradient, gamma50, is estimated at 2.1 with 95% confidence limits 1.4 and 3.6. With regard to normal tissue effects, the increase in total dose when going from CHART to CHARTWEL is moderated by the slightly longer overall treatment time in case of early morbidity while the introduction of the weekend gaps may moderate the effect for late-responding normal tissues with a long repair halftime. Tumour control at 3 years is expected to increase by some 7-14 percentage points (from 19% to 26-33%) whereas the incidence of moderate and severe early oesophagitis and pneumonitis is expected to increase by about 2 percentage points. The incidence of late morbidity, lung fibrosis and oesophageal strictures, is expected to increase by 3-4 percentage points. The analyses conclude that CHARTWEL is likely to improve the therapeutic ratio relative to CHART.

Carcinoma, Non-Small-Cell Lung↗

PubMed1981

Prostaglandin E2 in jejunal fluids and its potential diagnostic value for selecting patients with indomethacin-sensitive diarrhoea.

Since prostaglandins (PGs) appear to be important in the pathogenesis of secretory diarrhoea, a radioimmunoassay for determination of PGE2 was applied to purified samples of jejunal fluids aspirated at the ligament of Treitz. Studies on validation of the assay system included quantification of PGE2 following alkali-treatment of the samples, variation of the sample volume, and fractionation of immunoreactive- and tracer PGE2. In addition, the specificity of the assay system was confirmed by gas chromatography--mass spectrometry. In healthy volunteers (n = 22) the PGE2 concentration range was 5--205 pg/ml (99% confidence limits). Alcohol addicts (n = 27) with diarrhoea or steatorrhoea had PGE2 levels within the normal range. Values beyond the 99% upper confidence limit were observed in ten out of seventeen patients with chronic diarrhoea (205--340 pg/ml) and two out of fifteen patients with intermittent diarrhoea (265 and 275 pg/ml) classified as irritable bowel syndrome. In six patients with high PGE2 concentrations indomethacin treatment (25 mg x 4 daily) halved the associated diarrhoea and reduced PGE2 concentrations to normal levels. Subsequently, a double-blind multiple randomized clinical trial was carried out in two single patients. Indomethacin proved to be effective in preventing diarrhoea only in the patient with a raised PGE2 level (P less than 0.005).

Alcoholism↗

PubMed1991

Evaluation of 119 anaesthetics received after investigation for susceptibility to malignant hyperthermia.

A questionnaire was sent to the first 371 patients investigated for MH susceptibility at the Danish MH Register, in order to assess sequelae from the muscle biopsy and possible subsequent anaesthetic complications. The purpose was to evaluate both the safety of anaesthetizing MH-susceptible (MHS) patients without the use of trigger agents, and the safety of giving trigger agents to non-susceptible (MHN) patients. Eighty-eight per cent of patients alive replied to the questionnaire. Of these, 22% complained about discomfort at the site of the biopsy, 2% had experienced problems when needing a subsequent anaesthetic, and 0.9% had had trouble when applying for life or accident insurance. The median observation period for all patients following the muscle biopsy was 5.5 years (range 27 months-11 years). During this period, 36 MHS patients had been anaesthetized 52 times (28 general and 23 regional anaesthetics, data missing in one case) without any MH-related complications. None of the patients had received prophylactic dantrolene. Three MHE patients had received non-trigger anaesthetic agents on three occasions without development of MH. Thirty-five MHN patients had been anaesthetized 64 times, and 13 of these MHN patients had received trigger agents 26 times without any signs of MH. An estimate of the probability of clinical MH developing in MHN patients subsequently anaesthetized with trigger agents was found to be 0-24.7% (95% confidence limits), whereas the probability of clinical MH developing in MHS patients anaesthetized with non-trigger agents was 0-9.7% (95% confidence limits).

Adjuvants, Anesthesia↗

PubMed2000

Early bactericidal activity of paromomycin (aminosidine) in patients with smear-positive pulmonary tuberculosis.

The early bactericidal activity of the aminoglycoside paromomycin (aminosidine) in doses of 7.5 and 15 mg/kg of body weight was measured in 22 patients with previously untreated smear-positive pulmonary tuberculosis. The fall in log(10) CFU per milliliter of sputum per day during the first 2 days of treatment for 7 patients receiving a paromomycin dosage of 7.5 mg/kg/day was 0.066, with a standard deviation (SD) of 0.216 and confidence limits from -0.134 to 0.266, and that for 15 patients receiving 15 mg/kg/day was 0.0924, with an SD of 0.140 and confidence limits from 0.015 to 0.170. The difference between the mean and zero was not significant for the 7. 5-mg/kg dose group but was significant for the 15-mg/kg dose group (t = 2.55, P = 0.023). Since paromomycin has no cross-resistance with streptomycin and has no greater toxicity than other aminoglycosides, these results suggest that it has the potential to substitute for streptomycin in antituberculosis regimens and may be a particularly valuable addition to the drug armamentarium for the management of multidrug-resistant tuberculosis.

Adolescent↗

PubMed1961

Secretion of blood group substances in duodenal, gastric and stomal ulcer, gastric carcinoma, and diabetes mellitus.

The ABO blood group and ABH secretor status have been determined for 368 patients with a duodenal ulcer, 202 patients with a gastric ulcer, 83 patients with a stomal ulcer, 105 patients with gastric cancer, 102 patients with diabetes mellitus, and a control group of 610 subjects consisting of healthy persons and of patients with other conditions attending the same hospital. The results have been analysed in conjunction with those reported in two other large series. For duodenal ulcer the results show that the relative incidence among non-secretors compared with secretors is 1.80 to 1, with 95% confidence limits of 1.55 to 1 and 2.03 to 1. For gastric ulcer the relative incidence is 1.42 to 1, with 95% confidence limits of 1.16 to 1 and 1.74 to 1. Comparison of the results for the two types of peptic ulcer shows that they are significantly different from one another. For both types of ulcer, the estimated risk among non-secretors was similar for blood group O and for the other blood groups and the results suggest that the specific risks associated with blood group O and with non-secretion multiply one another. It is concluded that the mechanisms by which blood group O and non-secretion affect the risk of developing a gastric or duodenal ulcer are related to one another; but that they do not depend on the presence of the blood group substances in the secretions. The proportion of non-secretors among patients with a stomal ulcer (49%) was higher than among patients with a duodenal ulcer (37%) and the order of the relationship between non-secretion and the three types of peptic ulcer (stomal, duodenal, and gastric) was the same as that for blood group O. Other data suggest that there may be a slight increase in the risk of gastric cancer among non-secretors, but that the occurrence of diabetes mellitus is independent of ABH secretion.

ABO Blood-Group System↗