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Blue Cross Blue Shield Insurance Plans↗
Biomedical subjects
J Barlow
Publications and source records attributed to J Barlow.
Factors affecting dropout rate from cognitive-behavioral group treatment for bulimia nervosa.
The aim of this study was to retrospectively identify clinical variables assessed prior to treatment which were predictive of patients' dropping out versus completing a 10 week group cognitive-behavioral treatment program for bulimia nervosa. Following a lengthy initial assessment, 81 women meeting DSM-III-R criteria for bulimia nervosa (BN) were referred to one of twelve 10-week groups of 8 to 12 patients having bulimic symptoms. The dropout rate for those meeting full DSM-III-R criteria for BN was found to be 28.7%. A series of seven discriminant function analyses were performed to determine whether dropouts differed from completers in terms of depression, anxiety, difficulties in trust and relating to others, bulimic symptom severity, family environment, weight history and symptom duration and severity of bulimic cognitions. Of these, only the factor assessing difficulties trusting and relating to others was found to significantly discriminate dropouts from completers. Implications of the findings are discussed in terms of clinical and research relevance in the field of eating disorders.
Adult↗
Yield pressure, anatomy of the cardia and gastro-oesophageal reflux.
The yield pressure at which the cardia opens in response to gastric distension was measured in 155 subjects with and without gastro-oesophageal reflux (GOR) and after Nissen fundoplication. Yield pressure was measured by endoscopy or during oesophageal manometry. The median pressure was significantly lower in subjects with GOR than in those without (P < 0.0001). After successful Nissen fundoplication this pressure increased to supranormal values (P < 0.0001). There was a close relationship between yield pressure and the presence and size of hiatus hernia and also between yield pressure and the valvular appearance of the cardia at endoscopy. There was a significant correlation between yield pressure and oesophageal acid exposure. However, no relationship was observed between yield pressure and lower oesophageal sphincter pressure or intra-abdominal length. These results suggest that yield pressure is useful for assessment of the competence of the cardia, particularly after antireflux surgery. The competence of the cardia is greatly influenced by its anatomical structure.
Adolescent↗
Manometric asymmetry in the anal canal in controls and patients with fecal incontinence.
PURPOSE: This study was designed to ascertain the existence of manometric asymmetry in the anal canal in controls and in patients with fecal incontinence. METHODS: A computerized manometric technique with an eight-channel perfusion catheter was used. Coefficient of variation (CV, a mathematical expression of the degree or magnitude of deviation of a set of data points from the mean) was developed in this study as an index of anal canal manometric asymmetry. RESULTS: At 1 cm from the anal verge, mean CV was 9.3 and 8.7 percent in asymptomatic control males and females, respectively. During a maximum voluntary squeeze effort, mean CV in control males was 9.3 percent and was not significantly different (P = 0.28) from that in control females (7.8 percent). In 14 consecutive female patients with fecal incontinence, mean CV at rest (1 cm from the anal verge) was 21 percent and was significantly higher (P < 0.01) than in control females. Similarly, during a maximum voluntary squeeze effort, mean CV in patients with fecal incontinence was 20.5 percent and was significantly higher (P < 0.01) than in the female control group (7.8 percent). CONCLUSION: It is concluded that CV, a method of expressing anal sphincter manometric asymmetry, is a useful manometric parameter in the assessment of anorectal function.
Adult↗
Modulation of esophageal responses to magnetic stimulation of the human brain by swallowing and by vagal stimulation.
BACKGROUND & AIMS: Although magnetic stimulation of the human cerebral cortex activates corticoesophageal pathways, it is not known whether these pathways are mediated via brain stem neurons activated during swallowing and by vagal afferents. The aim of this study was to determine the effect of swallowing and vagal stimulation on esophageal electromyographic responses evoked by magnetic stimulation of the human cortex. METHODS: Magnetic stimulation of the cortex was performed in 7 subjects at variable intervals after swallows and at intervals ranging from 10 to 200 milliseconds after vagal stimulation in 5 subjects. RESULTS: Between swallows, cortical stimulation induced both early (10.1 +/- 0.5 milliseconds) and late (52.3 +/- 2.3 milliseconds) esophageal electromyographic responses with amplitudes of 66.9 +/- 23.4 microV and 32.9 +/- 7.4 microV, respectively. During swallowing, both responses were facilitated because their latencies decreased (8.9 +/- 0.5 milliseconds and 47.3 +/- 4.8 milliseconds, respectively), whereas their amplitudes increased (203.1 +/- 54 microV and 79.8 +/- 22.5 microV, respectively). Vagal stimulation facilitated the early cortically evoked response. Its latency decreased from 10.2 +/- 0.2 milliseconds to 8 +/- 0.2 milliseconds, whereas its amplitude increased from 145.1 +/- 44 microV to 230.5 +/- 41.6 microV. CONCLUSIONS: Corticoesophageal pathways activated by magnetic stimulation of the human cortex share the same population of brain stem motor neurons to the upper esophagus that are activated during swallowing and vagal stimulation.
Adult↗
Topographic mapping of cortical potentials evoked by distension of the human proximal and distal oesophagus.
We describe cortical potentials evoked by balloon distension of the proximal and distal oesophagus in 8 healthy right handed volunteers. Oesophageal stimulation was performed using a pump which rapidly inflated a 2 cm silicone balloon positioned either 3 cm distal to the upper oesophageal sphincter or 5 cm proximal to the lower oesophageal sphincter, at a frequency of 0.2 Hz, using inflation volumes which produced a definite but not painful sensation. Oesophageal evoked cortical potentials were recorded in all subjects with an initial negative and positive component (N1 and P1), followed by a second negative and positive component (N2 and P2) in 6 subjects. The morphology and the scalp topography of the N1 component elicited by proximal and distal oesophageal stimulation suggests activation of the primary somatosensory cortex and/or the insular. There was also evidence for hemispheric dominance for the N1 potential which was independent of handedness. The frontal emphasis of the proximal oesophageal N1 component, in contrast to the central emphasis of the distal oesophageal N1 component, suggests that different neuronal populations were activated by stimulation of the two sites. The frontal emphasis of the ensuing P1 component from both oesophageal sites suggests that it originates in a separate precentral source. The topography of the N2 components obtained by stimulation of either oesophageal site was similar to that of the N1 component, suggesting that they originate in similar areas of the cortex. The P2 component evoked by stimulation of both oesophageal sites was localised at the vertex. The inter- and intra-subject variation in the morphology of the N2 and P2 components suggests that secondary cortical processes related to cognition may be involved in their generation.
Adult↗
Diabetes: an adolescent's perspective.
The personal meaning and perceived impact of insulin dependent diabetes mellitus (IDDM) were investigated in an exploratory study of 51 Finnish adolescents aged between 13 and 17. Interview data were examined using continuous comparative analysis. The personal meaning of IDDM was described using the following categories: a habit; a little devil; a nightmare; stress; prison; death; and hell. A core concept to emerge was that of control. Young people felt IDDM controlled, or limited, their freedom and independence. Two main themes emerged in terms of the impact of IDDM in the lives of adolescents: a threat to life's equilibrium and a healthy lifestyle. Diabetes was viewed as a threat to physical, psychological and social well-being which disrupted the balance of life. In contrast, the other main category, a healthy lifestyle, revolved around the notion that having IDDM offered a unique opportunity to live a healthy life. The results provided a useful insight into the personal meaning of IDDM and serve to raise awareness of the problems and difficulties experienced by adolescents with this condition.
Adaptation, Psychological↗
Relations between upper abdominal symptoms and gastric distension abnormalities in dysmotility like functional dyspepsia and after vagotomy.
Postprandial bloating and fullness are commonly found both in dysmotility like functional dyspepsia, and after vagotomy but the relation between gastric accommodation and symptom production has not been investigated. Intragastric pressure levels and symptoms developed during controlled distension of the gastric fundus were recorded in nine patients with functional dyspepsia, in seven patients after truncal vagotomy, and in 11 healthy volunteers. The procedure was repeated after ingestion of a liquid nutrient meal (250 ml; 250 kcal). Gastric tone, expressed as the average value of pressure over the distension period was lower in controls (median: 11.3 mm Hg) than in either the dyspeptic patients (median: 16.48 mm Hg) or postvagotomy patients (median: 19.12 mm Hg) (p < 0.05). Meal ingestion reduced gastric tone in controls, but no significant change occurred in either the dyspepsia or the postvagotomy patients. Volumes at which discomfort was elicited by distension during fasting were lower both in dyspeptic patients (median: 210 ml) and in postvagotomy patients (median: 180 ml) than in healthy volunteers (median: 660 ml) (p < 0.05). Discomfort thresholds were unaffected by meal ingestion. These results suggest that a disturbance of gastric relaxation may be related to symptom development in dysmotility like functional dyspepsia, while similarities between dyspeptic patients and postvagotomy patients suggest that the impaired gastric accommodation in functional dyspepsia may be due to an underlying vagal defect.
Adult↗
Prognostic indicators in bulimia nervosa treated with cognitive-behavioral group therapy.
Prognostic indicators of short-term outcome were identified in 69 women with the DSM-III-R diagnosis of bulimia nervosa who participated in a weekly 10-session structured cognitive-behavioral outpatient group program. Prior to treatment, all subjects completed the computerized Diagnostic Interview Schedule (DIS), the Moos Family Environment Scale (FES), the Diagnostic Survey for Eating Disorders (DSED), the Beck Depression Inventory (BDI), the Hopkins Symptom Checklist, Revised (SCL-90-R), the Bulimic Cognitive Distortions Scale (BCDS), the Eating Disorders Inventory (EDI), and the Bulimic Symptoms Checklist (BSCL). The latter three scales were readministered on completion of the 10-week group. Symptom improvement was assessed by examining percentage reduction in binge frequency, purge frequency, and summed scores for the EDI subscales Bulimia, Drive for Thinness, and Body Dissatisfaction. The only significant predictor of improvement in binge frequency and bulimic cognitions was family environment. Conflicted, controlling, and over-organized family environments appear to impede both reductions in binge frequency and changes in bulimic cognitions. Reduction in vomit frequency was associated with weight history and with laxative or diuretic use. The implications for planning psychotherapeutic interventions in bulimia nervosa are discussed.
Adolescent↗
Operations research survey and computer simulation of waiting times in two medical outpatient clinic structures.
Outpatient services are increasingly recognised as an important component of health care provision and may be improved through the application of modern management techniques. We have performed a time and role audit of consultation and waiting times in two medical clinics using different queuing systems: namely, a serial processing clinic where patients wait in a single queue and a quasi-parallel processing clinic where patients are directed to the shortest queue to maintain clinic flow. Data collected were used to construct a computer simulation of patient flows in clinic. Assessment of patient satisfaction in the clinic process was determined using a self-administered questionnaire. Mean waiting time was shorter in the quasi-parallel processing clinic: 26 (SD 17) minutes compared with 36(24) minutes in the serial processing clinic. In the serial processing clinic 61% of patients waited more than 30 minutes compared with 41% in the quasi-parallel processing clinic. In the serial processing clinic 8% of 142 patients surveyed complained of the time spent waiting. The computer simulation we produced was able to determine waiting times with different clinic structures. The simulation showed that reductions in waiting time up to 30% might be achieved by changing our serial processing clinic to a quasi-parallel processing one. Performance of medical outpatient clinics can be improved by examining and changing clinic management. Computer simulation of outpatient clinics offers a means of assessing the impact of such changes on waiting time in clinic and on waiting lists.
Algorithms↗
Intra-operative patient-controlled sedation and patient attitude to control. A crossover comparison of patient preference for patient-controlled propofol and propofol by continuous infusion.
Intra-operative patient controlled sedation with propofol (bolus dose 18 mg over 5.4 s; lockout period 1 min) has been compared to continuous propofol infusion (3.6 mg.kg-1.h-1) in a randomised crossover study of 38 ASA 1 or 2 day surgery patients undergoing two-stage bilateral extraction of third molar teeth under local anaesthesia (76 procedures). Mean (SD) propofol used (mg.kg-1) was less with patient-controlled sedation (2.39 (1.28) than with the infusion (2.58 (0.84)) but the difference was not statistically significant. There were only minor differences between the methods in postoperative recovery of cognitive function and no differences for patient cooperation and surgeon's satisfaction with sedation. Patient-controlled sedation was preferred by 19 patients, continuous infusion by 10, with nine indifferent. Preferences, expressed as mild, moderate or strong, were significantly stronger for patient-controlled sedation (p < 0.05). Sedation was no deeper than eyelid closure with response to command in all 76 procedures. This level was reached in all 38 infusion cases but in only 26 cases with patient-controlled sedation, where 12 patients remained less sedated (p < 0.01). Patient-controlled sedation with propofol provided safe sedation and was strongly preferred over the infusion by a large proportion of patients.
Adult↗
A new automode switch algorithm for supraventricular tachycardias.
Patients with complete heart block on a spontaneous, or iatrogenic basis who also have recurrent supraventricular tachycardias, particularly atrial fibrillation and flutter, are often difficult to manage. Various techniques include: independently programmable maximum tracking and maximum sensor rates, limiting the maximum atrial tracking rate to the sensor response of the pacemaker, or automatically switching from DDDR to VVIR based upon the sensed atrial rate. This article will describe a mode switch algorithm that allows for an independently programmable atrial tachycardia detection rate (ATDR). This allows mode switching to occur only in response to the patient's pathological tachyarrhythmia, and not during normal upper rate response. The ATDR is based upon a filtered atrial rate, which will prevent an isolated premature beat from initiating the algorithm. In addition, the unit can be programmed to switch to either DDI, DDIR, VVI, or VVIR. Extensive event counters in the pulse generator allows the system to record and store the number of algorithm activations, the average atrial rate which triggered each mode switch, and the duration of the mode switch. These reports are accessible at each follow-up visit.
Algorithms↗
Beta adrenergic modulation of human upper intestinal propulsive forces.
beta Adrenoceptor blockade is known to accelerate transit through the small intestine without changing either the number or pattern of intestinal contractions. This study therefore tested the hypothesis that an increase in intraluminal aboral propulsive force may contribute to this transit acceleration. Twenty paired studies were performed, in 10 healthy volunteers, after oral administration of either 100 mg atenolol (a selective beta 1 antagonist) or matched dummy tablets according to a double blind, randomised protocol. The frequency of occurrence of, and the propulsive force exerted by, traction events related to intestinal contractions were measured, using a combined traction force detector and manometry assembly. After atenolol, a consistent increase in the force generated per traction event was noted, both for propagating contractions mean (SEM) (12.0 (1.8) g v control 5.9 (0.07) g; p < 0.05) and for stationary (11.6 (1.4) g v control 7.0 (0.7) g; p < 0.05). In contrast no change in the number of traction events was noted (control v atenolol = 1.6 (0.3) v 1.64 (0.4) per min for propagating and 0.7 (0.1) v 0.85 (0.16) per min for stationary contraction; p > 0.05). beta Adrenoceptor blockade thus increases the propulsive force generated by intestinal contractions, possibly by removing a sympathetic neural inhibition of intestinal tone.
Adult↗
Human small intestinal contractions and aboral traction forces during fasting and after feeding.
Small intestinal intraluminal pressure activity and aboral traction forces were explored in 19 healthy volunteers using a combined manometry and traction force detecting assembly sited in the upper small intestine. Each aboral traction event was classified as being associated with either a propagating or a stationary contraction and its force measured. During phase I no contractions or traction events were seen. During phase II, traction events related to propagating contractions mean (SEM) (2.2 (0.2)/min) and to stationary contractions (0.3 (0.1)/min) generated similar force/event (7.5(0.9 g v 8.7 (1.4) g, p > 0.05). During phase III, all traction events were related to propagating contractions and generated 9.3 (2.4) g force/event (p > 0.05 v phase II). After feeding, traction events related to propagating contractions generated similar force/event to those related to stationary contractions (5.9 (1.0) g v 9.3 (2.7) g, p > 0.05 v each other and v fasting). No consistent pattern was seen in the temporal distribution of the traction events or in the pattern of the amplitude of the force of successive traction events.
Adult↗
Relaxation responses of the human proximal stomach to distension during fasting and after food.
The responses of the human proximal stomach to distension were studied in 22 healthy volunteers using an intragastric polyethylene bag, inflated progressively in 30-ml steps until the limit of tolerated volume was reached. Three successive inflations were carried out during the fasting state followed by a fourth inflation after ingestion of 250 ml of either a nutrient meal or isosmolar saline. The first inflation showed an initial nonlinear pressure rise (slope of logged pressure vs. volume = 114.6 +/- 10.0 log mmHg/ml x 10(-5)), which was then followed by the development of a plateau phase, in which further distension did not increase intragastric pressure. The slopes of the subsequent fasting inflations were significantly lower than that of the first inflation (P < 0.01) but were similar to each other (slope 83.0 +/- 5.4 and 79.8 +/- 5.7 log mmHg/ml x 10(-5)), indicating that distension-induced gastric relaxation had occurred. After saline ingestion, responses to distension were similar to those during the fasted state. After the nutrient meal ingestion, however, the slope decreased to 60.3 +/- 7.7 log mmHg/ml x 10(-5) (P < 0.01 vs. saline), indicating nutrient-induced gastric relaxation. Our study demonstrates that the pressure-volume characteristics of the proximal stomach are modulated both by distension and by the presence of nutrients in the upper gut, which appear to operate independently.
Adult↗
Esophageal myoelectric responses to magnetic stimulation of the human cortex and the extracranial vagus nerve.
We describe the use of magnetic stimulation of the human motor cortex and the extracranial vagus nerve in the neck to study human esophageal electromyographic (EMG) responses. Diffuse cortical stimulation produced both an early and a late EMG response in the proximal esophagus with latencies of 10.9 +/- 0.5 and 43.4 +/- 4.3 ms, respectively. Increasing the stimulation intensity increased the amplitude and duration, but reduced the latency, of the early response (P < 0.01), whereas the late response remained unchanged. The early response, but not the late response, was facilitated when cortical stimulation was performed during valsalva maneuver. Maximal early response amplitudes were obtained by focal stimulation of either hemisphere 4-8 cm lateral to the vertex. Stimulation of the neck over the extracranial vagus nerve at the angle of the jaw also produced an early and a late EMG response in the proximal esophagus with latencies of 4.3 +/- 0.4 and 56.8 +/- 14.5 ms, respectively. Early responses were also recorded in the midesophagus and distal esophagus from either cortical or vagal stimulation, but amplitudes were smaller and rise times were longer, suggesting passive "volume conduction" from the proximal esophagus. Comparison of laryngeal, pharyngeal, and esophageal early EMG responses showed similar amplitudes and rise times, suggesting that the action potentials were generated locally at each site and that true esophageal responses were being detected.
Adult↗
Immunochemical detection of inducible NO synthase in human lung.
Type II (inducible) nitric oxide synthase (NOS) may play an important role in pulmonary pathophysiology, yet it remains controversial whether human tissues are capable of expressing this protein. Therefore, a polyclonal antibody (8196) was raised against type II NOS from induced RAW 264.7 macrophages and used to investigate the expression of this enzyme in human lung tissue. Anti-type II NOS antibody did not cross-react with either neuronal (type I) or endothelial (type III) constitutive NOS, whereas a 130-kDa protein was detected in cytosol from induced macrophages or liver removed from lipopolysaccharide (25 mg/kg)-treated rats. Cells or tissues that lacked NOS activity did not express immunoreactive proteins. Similarly, in grossly normal human lung tissue, no immunoreactivity was detected with the anti-type II NOS antibody. In contrast, strong immunoreactivity was detected in alveolar macrophages present in lung tissue from a patient with bronchiectasis and acute bronchopneumonia. These data demonstrate that human alveolar macrophages are able to express type II NOS and support a role for this enzyme in pulmonary inflammatory pathophysiology.
Acute Disease↗
Cardiovascular effects and hemodynamic mechanism of action of the novel, nonpeptidic renin inhibitor A-74273 in dogs.
A-74273 is a nonpeptidic, potent inhibitor of human and canine renin (IC50 = 3.1 and 43 nM, respectively, in plasma at pH 7.4) and has been shown to be orally active in dogs. To determine the hemodynamic mechanism underlying this renin inhibitor's hypotensive activity, the cardiac and hemodynamic effects of A-74273 were studied in sodium-depleted and sodium-replete pentobarbital-anesthetized dogs. Vehicle [5% dextrose in water (V, D5W), n = 8] or a single dose of A-74273 was administered intravenously (i.v.) as a bolus followed by a 30-min infusion (one tenth the bolus dose per minute). Baseline mean arterial pressure (MAP) was similar among all treatment groups, but baseline plasma renin activity (PRA) was increased in the sodium-depleted dogs as compared with the sodium-replete dogs. In sodium-depleted dogs (n = 7-8/dose), MAP decreased maximally as compared with baseline by 4 +/- 1, 19 +/- 3, and 23 +/- 3% during infusion of A-74273 at doses of 0.001, 0.01, and 0.1 mg/kg/min, respectively (p < 0.05 vs. baseline or V). The two highest infusion doses also produced significant reductions (p < 0.05 vs. baseline and V) in systemic vascular resistance (SVR, 21 +/- 2 and 25 +/- 2%) and left ventricular end-diastolic pressure (LVEDP, 40 +/- 8 and 47 +/- 12%). In sodium-replete dogs (n = 4/dose), an infusion dose of 0.01 mg/kg/min elicited no hemodynamic response, whereas 0.1 mg/kg/min reduced MAP by 13 +/- 2% (p < 0.05 vs. baseline) and SVR by 7 +/- 6%.(ABSTRACT TRUNCATED AT 250 WORDS)
Administration, Oral↗