The value of routine expiratory chest films in the diagnosis of pneumothorax.
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Adolescent↗
Biomedical subjects
C Williams
Publications and source records attributed to C Williams.
Regional differences in gastrointestinal processing and absorption of epidermal growth factor in suckling rats.
Gastrointestinal processing and absorption in vivo of 125I-labeled epidermal growth factor (125I-EGF) was studied in isolated stomach, jejunum, and ileum of 12-day-old suckling rats. Dose dependency and regional differences in the processing and absorption of EGF were determined. At 60 min after administration of 125I-EGF into the isolated gastric lumen, greater than 90% of radioactive material was recovered from gastric wall and lumen in both suckling and weanling rats. On the other hand, a considerable amount of EGF was absorbed (in immunoreactive and receptor active form) from isolated jejunum and ileum of suckling rats. The absorption of EGF from isolated jejunum and ileum increased linearly with the dose of EGF administered up to 1 microgram/rat; absorption of orogastrically administered EGF was also increased linearly with the dose of EGF administered (up to 5 micrograms/rat). Reverse-phase high-performance liquid chromatographic analysis of tissue extracts demonstrated that 125I-EGF is stable in gastric lumen but only partially stable in the jejunal lumen. Carboxy-terminally processed forms of EGF were detected in the luminal flushings of jejunum and ileum and in the wall of the stomach, jejunum, and ileum. 125I-des(48-53)EGF was found in ileal flushings and in the walls of the stomach, jejunum, and ileum, whereas 125I-des(53)EGF and 125I-des(49-53)EGF were detected in jejunal flushings. Receptor binding of 125I-des(53)EGF was significantly greater (by 57%) than that of intact 125I-EGF, but receptor binding of 125I-des(49-53)EGF and 125I-des(48-53)EGF was greatly diminished by 57 and 86%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
Absorption↗
The effect of long-term intravenous calcitriol administration on parathyroid function in hemodialysis patients.
Secondary hyperparathyroidism is common in dialysis patients. Intravenous calcitriol has proven to be an effective therapy for the reduction of parathyroid hormone (PTH) levels. However, the effect of i.v. calcitriol on parathyroid function, defined as the sigmoidal PTH-calcium curve developed during hypocalcemia and hypercalcemia, has not been evaluated during the prolonged administration of i.v. calcitriol. Six hemodialysis patients with marked secondary hyperparathyroidism, PTH levels greater than 500 pg/mL (normal, 10 to 65 pg/mL), were treated for 42 wk with 2 micrograms of i.v. calcitriol after each hemodialysis. Parathyroid function was evaluated before and after 10 and 42 wk of calcitriol therapy. Between baseline and 42 wk, the basal PTH level decreased from 890 +/- 107 to 346 +/- 119 pg/mL (P less than 0.02) and the maximally stimulated PTH level decreased from 1293 +/- 188 to 600 +/- 140 pg/mL (P less than 0.01). In addition, calcitriol administration significantly decreased PTH levels throughout the hypocalcemic range of the PTH-calcium curve. Although the slope of the PTH-calcium curve (with maximal PTH as 100%) decreased between baseline and 42 wk (P less than 0.05), the set point of calcium did not change. Two patients with a decrease in both basal and maximally stimulated PTH levels after 10 wk of calcitriol, developed marked hyperphosphatemia between 10 and 42 wk; this resulted in an exacerbation of hyperparathyroidism despite continued calcitriol therapy. In conclusion, prolonged i.v. calcitriol administration is an effective treatment for secondary hyperparathyroidism in hemodialysis patients provided that reasonable control of the serum phosphate is achieved. In addition, the slope of the PTH-calcium curve may be a better indicator of parathyroid cell sensitivity than the set point of calcium.
Adult↗
The treatment of spondylotic cervical myelopathy by multiple subtotal vertebrectomy and fusion.
The authors report their experience in the treatment of cervical spondylotic myelopathy by multiple subtotal vertebrectomy and fusion. There were 27 cases with a mean age of 66.9 years. The clinical assessment was carried out using both the Nurick and the Japanese Orthopaedic Association (JOA) grading pre- and post-operatively at 6 months. The post-operative radiological assessment was done at 3 and 6 months. Two cases died from unrelated medical problems. There were three cases of graft dislodgement. Clinical improvement was detected in 80% of cases using the Nurick grading and in 88% of cases using the JOA scoring. No cases deteriorated neurologically after operation. Bony fusion was achieved in 96% of the surviving cases by 6 months. Multiple subtotal vertebrectomy and fusion is therefore an effective method for the treatment of cervical spondylotic myelopathy.
Adult↗
Mental performance in CAPD.
Impaired cognitive function is part of an array of neurologic manifestations seen in patients with end stage renal disease. We investigated whether a difference exists in mental performance between patients on hemodialysis and on CAPD. The trial test A was administered in standardized fashion, and the time required to complete the test was used as a function of mental performance. A group of age and sex matched healthy controls was included for comparison. The results indicate that performance in the trail test A was markedly different among the three groups; controls did the test in 30.7 +/- 2.4 sec (n = 17), CAPD in 47.2 +/- 6.4 (p less than 0.05) and hemodialysis patients in 82.6 +/- 11 (p less than 0.005). Patients on CAPD completed the test significantly faster than those on hemodialysis (p less than 0.05). This observation of a significantly better mental performance by patients in CAPD than in patients in hemodialysis is likely to be multifactorial, and its significance is unclear, but this may be of interest to the clinician and patients contemplating different dialysis modalities.
Humans↗
Evaluation of the safety, recovery, half-life, and clinical efficacy of antithrombin III (human) in patients with hereditary antithrombin III deficiency. Cooperative Study Group.
Antithrombin III (Human) (AT III) was administered to 18 patients with documented hereditary AT III deficiency. In eight patients with no ongoing clinical symptoms of thrombosis, the percent increase per unit AT III infused per kilogram of body weight ranged from 1.56% to 2.74%, and the half-life from 43.3 to 77.0 hours. No significant difference was noted between patients receiving and those not receiving coumarin therapy. In clinically ill patients, the in vivo recovery was significantly lower and ranged from 0.64% to 1.90% increase per unit AT III infused/kg. Efficacy of AT III was evaluated in 13 patients for the prevention or treatment of thrombosis. AT III was efficacious as assessed by the absence of thrombotic complications after surgery and/or parturition, and the nonextension and nonrecurrence of thrombosis in patients exhibiting an acute thrombotic episode. No side effects were noted. Follow-up studies indicated no hepatitis B seroconversion and no alanine aminotransferase elevations in patients who were not transfused with other blood products.
Adult↗
Parental origin of del(15)(q11-q13) in Angelman and Prader-Willi syndromes.
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Abnormalities, Multiple↗
Degeneration of spinocerebellar neurons in amyotrophic lateral sclerosis.
The selective involvement of spinocerebellar neurons in sporadic amyotrophic lateral sclerosis was investigated using two monoclonal antibodies that have neuronal subset specificity in human spinal cord. In normal control subjects, monoclonal antibody 6A2 showed specificity for neurons of the dorsal nucleus of Clarke, the cells of origin of the dorsal spinocerebellar tract. Immunoreactive neurons were also observed in locations corresponding to the central cervical nucleus and spinal border region, containing neurons of the cervicospinocerebellar and ventral spinocerebellar tracts, respectively. The latter two neuronal subsets are indistinguishable from surrounding neurons when conventional histological stains are used. Antigen 6A2 was distributed on surfaces of neuronal somas and proximal neurites and extended into the extracellular space. A second antibody, monoclonal antibody 44.1, labeled the cytoplasm of neuronal somas and neurites, including all monoclonal antibody 6A2-reactive cells and alpha motoneurons. In spinal cords of all 5 patients with amyotrophic lateral sclerosis, monoclonal antibody 6A2 reactivity in the majority of spinocerebellar neurons was absent or localized to the somal cytoplasm, which still stained with monoclonal antibody 44.1. In more severely involved tissues, there was loss of some spinocerebellar neurons and a corresponding loss of monoclonal antibody 44.1 reactivity. These findings confirm involvement of the spinal cord components of the spinocerebellar system at all levels in sporadic amyotrophic lateral sclerosis and suggest that some surface molecules are modified during the degenerative process.
Adult↗
Influence of fluid intake on endurance running performance. A comparison between water, glucose and fructose solutions.
The aim of the present study was to compare the influence of drinking water, a carbohydrate-electrolyte solution, containing additional free glucose (Glucose) or the same carbohydrate-electrolyte solution containing additional fructose (Fructose), on running performance. Twelve endurance-trained recreational runners volunteered to take part in this study; 9 completed the three and all 12 completed two trials. The subjects were randomly assigned to one of the three trials: Water, Glucose or Fructose. In each trial the subjects were required to run 30 km as fast as possible on a motorized treadmill, instrumented so that they could control its speed. The carbohydrate-electrolyte solutions contained a total of 50 g carbohydrate, 20 g as a glucose polymer. The Glucose solution contained an additional 20 g free glucose and the Fructose solution contained an additional 20 g fructose rather than glucose. The osmolality of the Glucose and Fructose solutions was approximately 300-320 mosmol and the energy equivalent of both solutions was 794 kJ.l-1. The subjects ingested 1 l fluid throughout each run. The running times were not significantly different, being 129.3 (+/- 17.7) min, 124.8 (+/- 14.9) min and 125.9 (+/- 17.9) min for Water, Glucose and Fructose respectively. There was a decrease (P less than 0.05) in running speed over the last 10 km of the Water trial from 4.14 (+/- 0.55) to 3.75 (+/- 0.86) m.s-1, which did not occur in the carbohydrate trials. Blood glucose concentrations during the Water trial decreased from 15 km onwards and at the end of the run they were significantly (P less than 0.05) lower than the value recorded at 15 km.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
The hormonal responses to repetitive brief maximal exercise in humans.
The responses of nine men and nine women to brief repetitive maximal exercise have been studied. The exercise involved a 6-s sprint on a non-motorised treadmill repeated 10 times with 30 s recovery between each sprint. The total work done during the ten sprints was 37,693 +/- 3,956 J by the men and 26,555 +/- 4,589 J by the women (M greater than F, P less than 0.01). This difference in performance was not associated with higher blood lactate concentrations in the men (13.96 +/- 1.70 mmol.l-1) than the women (13.09 +/- 3.04 mmol.l-1). An 18-fold increase in plasma adrenaline (AD) occurred with the peak concentration observed after five sprints. The peak AD concentration in the men was larger than that seen in the women (9.2 +/- 7.3 and 3.7 +/- 2.4 nmol.l-1 respectively, P less than 0.05). The maximum noradrenaline (NA) concentration occurred after ten sprints in the men (31.6 +/- 10.9 nmol.l-1) and after five sprints in the women (27.4 +/- 20.8 nmol.l-1). Plasma cardiodilatin (CDN) and atrial natriuretic peptide (ANP) concentrations were elevated in response to the exercise. The peak ANP concentration occurred immediately post-exercise and the response of the women (10.8 +/- 4.5 pmol.l-1) was greater than that of the men (5.1 +/- 2.6 pmol.l-1, P less than 0.05). The peak CDN concentrations were 163 +/- 61 pmol.l-1 for the women and 135 +/- 61 pmol.l-1 for the men. No increases in calcitonin gene related peptide (CGRP) were detected in response to the exercise. These results indicate differences between men and women in performance and hormonal responses. There was no evidence for a role of CGRP in the control of the cardiovascular system after brief intermittent maximal exercise.
Adult↗
Continuous intramuscular pH measurement during the recovery from brief, maximal exercise in man.
Muscle pH and temperature were measured before, and continuously for 30 min after, a 30-s maximal sprint exercise in ten subjects. These measurements were made with a needle-tipped pH electrode and a thermocouple placed in vastus lateralis. Venous blood samples were collected for pH, lactate and catecholamine estimations and measurements were also made of the arterial blood pressure and heart rate. The muscle and venous pH decreased from 7.17 +/- 0.01 (mean +/- SEM) and 7.39 +/- 0.01 to 6.57 +/- 0.04 and 7.04 +/- 0.03, respectively, in response to the exercise. No significant recovery occurred in either pH measurement for 10 min, after which muscle pH increased to 7.03 +/- 0.03 and venous pH to 7.29 +/- 0.01 by 30 min. Muscle temperature increased by 2.1 degrees C with exercise and also failed to return to pre-exercise values by 30 min. Blood lactate concentration increased from 0.75 +/- 0.04 mmol l-1 before exercise to a peak value of 15.76 +/- 0.35 mmol l-1 5 min after completion of the exercise, and then declined slowly to 10.30 +/- 0.61 mmol l-1 by 30 min. Arterial blood pressure increased transiently with exercise but recovered rapidly, whereas the exercise-induced tachycardia was sustained throughout the recovery period. The recovery from the metabolic and cardiovascular responses to maximal sprint exercise in man is incomplete 30 min after cessation of the exercise.
Adult↗
delta F508 frequency and associated haplotypes near the cystic fibrosis locus in the Yugoslav population.
Chromosomes from 19 unrelated Southern Yugoslav families in which cystic fibrosis (CF) occurs were analysed for the presence of the delta F508 mutation, using polymerase chain reaction amplification followed by dot blot and polyacrylamide gel analysis. Of the 38 CF chromosomes, 15 (39.5%) carry the delta F508 deletion. Restriction fragment length polymorphism haplotypes for KM19/PstI, XV2c/TaqI and J3.11/PstI marker loci were determined and are compared for a total of 34 N and 37 CF chromosomes.
Cystic Fibrosis↗
The incidence of delta F508 CF mutation, and associated haplotypes, in a sample of English CF families.
Data are presented for delta F508 screening and KM19/XV2c haplotype analysis of 195 cystic fibrosis (CF) chromosomes from the British Caucasian population. We report the frequency of delta F508 in this group to be 80% and find pronounced disequilibrium between the deletion and the KM 2, XV 1 haplotype. Haplotype analysis of 71 normal chromosomes is also presented. We report one individual who had meconium ileus and who does not have the delta F508 mutation on either chromosome.
Cystic Fibrosis↗
Population change and environment in central and eastern Kenya.
"This paper, in compiling a case-study of six districts in Central and Eastern Provinces of Kenya, addresses the two poles of theory regarding population, environment, and economy--restricted growth and degradation versus induced change and intensification. The paper presents data on population change, and explores its relevance for changing patterns of resource use and economic opportunity.... Changes in population density between the 1969 and 1979 censuses are compiled, using regions of agroclimatic potential as surrogates for indicators of economic development.... Trends in urbanization are also analysed, to illuminate the dynamics of rural-urban linkages."
Africa↗
Effects of warm-up on blood gases, lactate and acid-base status during sprint swimming.
A standardized 200-m front crawl sprint swim (SpS) was used to evaluate the effects of warm-up on pH, blood gases, and the concentrations of lactate ([La-]) and bicarbonate ([HCO3-]) in arterialized and venous blood. Eight trained male swimmers performed two randomly assigned 200-m front crawl swims at previously determined intensities corresponding to 120% VO2max. One swim was preceded by a warm-up (WU trial) which consisted of a 400-m front crawl swim (82% VO2max), 400-m flutter kicking (45% VO2max), and 4 x 50-m front crawl sprints (111% VO2max). The second was performed without warm-up (NWU trial). Blood was sampled from a hyperemized earlobe and an antecubital vein before the warm-up, 9 min after the warm-up (1 min before the swim), immediately following the SpS, and at 2, 5, 10, and 20 min after the SpS. The warm-up exercise resulted in a higher pre-SpS [La-] in arterialized blood (3.1 +/- 0.4 and 1.7 +/- 0.4 mmol x l-1, p less than 0.05), a higher hydrogen ion concentration ([H+]) in venous blood (45.9 +/- 0.9 and 42.2 +/- 0.8 nmol x l-1, p less than 0.001), and a lower arterialized blood [HCO3-] (25.1 +/- 0.9 and 22.2 +/- 0.8 mmol x l-1, p less than 0.05). The SpS was accompanied with higher heart rates during the WU trial (178 +/- 3 and 169 +/- 3 bpm; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Endurance running performance in athletes with asthma.
Laboratory assessment was made during maximal and submaximal exercise on 16 endurance trained male runners with asthma (aged 35 +/- 9 years) (mean +/- S.D.). Eleven of these asthmatic athletes had recent performance times over a half-marathon, which were examined in light of the results from the laboratory tests. The maximum oxygen uptake (VO2max) of the group was 61.8 +/- 6.3 ml kg-1 min-1 and the maximum ventilation (VEmax) was 138.7 +/- 24.7 l min-1. These maximum cardio-respiratory responses to exercise were positively correlated to the degree of airflow obstruction, defined as the forced expiratory volume in 1 s (expressed as a percentage of predicted normal). The half-marathon performance times of 11 of the athletes ranged from those of recreational to elite runners (82.4 +/- 8.8 min, range 69-94). Race pace was correlated with VO2max (r = 0.863, P less than 0.01) but the highest correlation was with the running velocity at a blood lactate concentration of 2 mmol l-1 (r = 0.971, P less than 0.01). The asthmatic athletes utilized 82 +/- 4% VO2max during the half-marathon, which was correlated with the %VO2max at 2 mmol l-1 blood lactate (r = 0.817, P less than 0.01). The results of this study suggest that athletes with mild to moderate asthma can possess high VO2max values and can develop a high degree of endurance fitness, as defined by their ability to sustain a high percentage of VO2max over an endurance race. In athletes with more severe airflow obstruction, the maximum ventilation rate may be reduced and so VO2max may be impaired. The athletes in the present study have adapted to this limitation by being able to sustain a higher %VO2max before the accumulation of blood lactate, which is an advantage during an endurance race. Therefore, with appropriate training and medication, asthmatics can successfully participate in endurance running at a competitive level.
Adult↗
The controllable lifestyle factor and students' attitudes about specialty selection.
Questionnaires were distributed to 346 fourth-year students in nine medical schools. The students were asked to state their selected specialty and to rank the importance that each of 25 influences, listed as questionnaire items, had had in making their choice of specialty. Factor analysis showed that particular items were significantly associated with particular factors. The first factor emphasized perceived lifestyle (items in this category gave importance to remuneration, personal time, and prestige); the second factor emphasized cerebral activities and a practice orientation; and the third factor stressed altruistic values and attitudes. The authors classified the selected specialties into three groups: those characterized as having a non-controllable lifestyle (NCL), those with a controllable lifestyle (CL), and surgery. (CL specialties were defined as those that allow the physician to control the number of hours devoted to practicing the specialty.) Data were analyzed using factor analysis, and analysis of variance, and the Scheffé method. Analysis indicated that the perceived lifestyle factor was most closely associated with the responses of those students choosing CL specialties. Furthermore, this factor received the highest total loading of the three factors from all the students, thus indicating the level of interest in lifestyle factors. Responses to items that defined the cerebral and practice factor were highest from the group of students choosing CL specialties and lowest from the group choosing NCL specialties. The NCL students scored highest in the altruism factor and the CL students scored the lowest. The surgery and NCL groups were similar in attitude patterns, and both were substantially different in attitude patterns from those of the CL groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Altruism↗
Job satisfaction: comparing CC and med/surg nurses.
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Career Mobility↗