Intersubject variability of functional areas in the human visual cortex

A review of studies made in the compost production industry showed the biological agents posing a risk for workers were fungi and thermophile bacteria, gram-negative bacteria and endotoxins, with a prevalent inhalation exposure to airborne contaminated dusts. Medical examinations revealed cases of extrinsic allergic alveolitis due to A. fumigatus, and more frequently irritative and infectious disorders occurring especially in conditions of poor environmental hygiene and macroscopic dust pollution. For the evaluation of the air dispersion of microorganisms, which is high in compost transport and turning operations, at present no exposure limit values are available for biological agents; nevertheless, the concentrations measured were often higher than the limit values proposed for other manufacturing sectors by individual authors and by regulatory agencies in Europe, and were comparable to values observed in other industrial settings for which adverse health effects have been shown. Although the number of studies available are few in number, the results suggest that the hazards posed by microorganisms and the poor environmental hygiene conditions often encountered can undoubtedly be a source of risk for workers, which at present is difficult to establish but significant considering the high airborne concentrations of contaminated dust. Besides technical measures to avoid environmental macroscopic dispersion of dusts, measurement of airborne microbiological contaminants is also recommended. Health surveillance needs to be aimed at identifying subjects with hypersusceptibility to the infectious action of the pathogenetic and/or allergenic agents or with hypersensitivity to the same, and also to periodic control of respiratory organs.     

Videoendoscopic diagnosis of esophageal motility disorders

PURPOSE: Looking for a valid, reliable, and feasible method to collect data on the performances of practicing family physicians, the authors compare the measurement characteristics of a multiple-station examination (MSE) using standardized patients with those of a video assessment of regular consultations in daily practice (practice video assessment, PVA). METHOD: In a cross-sectional study, consultations of 90 family physicians were videotaped both in an MSE and in their daily practices. Peer-observers used a validated instrument (MAAS-Global) to assess the physicians' communication with patients and their medical performances. The physicians were randomly divided into two groups, comparable for demographic characteristics, and half underwent the assessments in reverse order to test for time-order effects. Content validity, criterion validity, reliability, and feasibility of the two methods were compared. RESULTS: Content validity of the PVA was superior to that of the MSE, since the domain of general family practice care was better covered. Observed participants judged the videotaped practice consultations to be "natural," whereas hardly any family physician, after reviewing the videotaped consultations of the MSE, recognized his or her usual working style. Specific criteria made it possible to standardize real practice. Concerning criterion validity, only the medical-performance components of the two methods correlated. No correlation was found for the communication components. Real-practice performance proved to be less influenced by observation than was performance during the MSE. The reliabilities of the two methods, expected to be better in the controlled MSE, were comparable. The administration of the PVA was more flexible, less costly, and better accepted by the family physicians than was that of the MSE. CONCLUSION: Assessment for quality improvement of family physicians' practices by video observation in daily practice is superior to video assessment in a simulated setting using standardized patients.     

Hot water swallows improve symptoms and accelerate esophageal clearance in esophageal motility disorders

The mechanism of action of the synthetic growth hormone (GH)releasing peptide hexarelin is not yet fully understood. Although a direct effect on pituitary cells has been demonstrated, the peptide is also active at hypothalamic level, where specific binding sites have been found. The observation that hexarelin acts synergistically with GH-releasing hormone (GHRH) in releasing GH has suggested that it might suppress endogenous somatostatin secretion. As somatostatin is also inhibitory on TSH secretion, to verify the occurrence of modifications of the somatostatinergic tone induced by hexarelin, we studied its effects on TRH-induced TSH secretion. Seven normal subjects (4 women and 3 men aged 24-29 years) underwent the following tests on 3 different days: a) TRH (200 micrograms/l i.v.) + placebo; b) hexarelin (1 microgram/Kg bw i.v.) + placebo c) combined TRH + hexarelin administration. Hexarelin induced significant and similar increases in serum GH levels when given in combination either with placebo or with TRH (1217 +/- 470 vs 986 +/- 208 micrograms/min/l p:NS), while no modifications of GH levels were seen after TRH + placebo. Serum TSH levels were unmodified by hexarelin + placebo injection. The TSH increase elicited by hexarelin + TRH was superimposable to that elicited by TRH + placebo (1124 +/- 530 and 1273 +/- 380 mU/min/l respectively). Circulating PRL levels slightly increased after hexarelin + placebo too (897 micrograms/min/l), and the PRL response to hexarelin + TRH was slightly, although not significantly, greater than that observed after TRH + placebo (2680 +/- 1517 and 2243 +/- 1108 micrograms/min/l, respectively). In conclusion, our data show that hexarelin does not alter basal and TRH-stimulated TSH secretion, thus suggesting that it does not inhibit somatostatin release. Furthermore a modest PRL-releasing effect of this peptide has been confirmed.     

Solid phase radionuclide esophageal motility in polymyositis and dermatomyositis

Polymyositis (PM) and dermatomyositis (DM) may be associated with motor dysfunction of the entire gastrointestinal tract. Abnormal esophageal motor function is a well-recognized complication of these diseases. In this study, we used a solid phase esophageal study to evaluate the motor function in patients with PM or DM. Twenty-three patients and 36 age-matched normal volunteers were studied. Each subject was placed in a supine position above a gamma camera linked to a computer and was given a 4-ml bolus of solid gelatin containing 1 mCi of Tc-99m phytate. Data were acquired in the list mode. A computer method modified from Kelim and Wald and Russell et al. was used to calculate the following: A) total mean transit time (MTT); B) residual fraction after the first swallow (RF); and C) retrograde index (RI). All values are presented as mean +/- standard deviation (SD). The Student's t-test was used to test statistical significance. Our preliminary results suggest: 1) delayed esophageal emptying is common (17/23) in PM/DM, indicating frequent malfunction of the smooth muscle of the upper gastrointestinal tract in PM/DM and 2) measurement of esophageal motility may monitor disease activity in PM/DM.     

Patterns of esophageal motility in patients with stable bulimia

OBJECTIVES: A high prevalence of GI motility disturbances, including deranged esophageal motility, has previously been reported in patients with eating disorders; altered esophageal and gastric motility have been suggested to play an important role in these disease processes. We sought to confirm this association in an independent patient population. METHODS: We performed esophageal manometry in 12 patients with eating disorders (eight patients with bulimia and four with overlap syndromes, including both anorexia and bulimia features) and 12 sex-matched controls. All subjects completed a symptom questionnaire. Motility testing was performed in the standard fashion using a low compliance water perfusion catheter and computerized digital data capture. Coded tracings were interpreted in a blinded fashion. RESULTS: All 24 studies showed normal motility patterns [95% confidence interval for abnormal esophageal motility in eating disorders patients (0, 0.27)]. Mean lower esophageal sphincter pressure was 24.4 mm Hg in patients and 21.8 in controls; all relaxed normally. Mean esophageal body contraction amplitude 3 cm above the lower esophageal sphincter was 82.6 mm Hg in patients and 84.3 in controls; waveform morphology and progression met normal criteria in all studies. Eight of 12 patients reported dysphagia, odynophagia, or both, compared with 1 of 12 controls; patients demonstrated a pattern of increased overall GI symptomatology compared to controls. CONCLUSIONS: We conclude that disordered esophageal motility is uncommon among stable eating disorder outpatients with bulimic features, and that dysphagia and odynophagia are rarely associated with disordered motility in this group.     

Reversible esophageal motility disorder in a patient with sarcoidosis

Hysterosalpingo-contrast sonography was compared with sonographically controlled selective tubal catheterization (STC) in 26 infertile women who complained of infertility. Both procedures were carried out on a single examination date. A group of 10 patients first underwent hysterosalpingo-contrast sonography followed by STC, while 16 first had STC followed by hysterosalpingo-contrast sonography. The main outcome measure was tubal patency. A total of 52 Fallopian tubes was assessed. Hysterosalpingo-contrast sonography showed 39 tubes (75%) and STC 46 (89%) to be patent, 13 tubes (25%) and six tubes (12%) were diagnosed to be proximally occluded, by means of hysterosalpingo-contrast sonography and STC respectively. Concordant diagnosis with both methods was made in 43 of 52 tubes (83%). When hysterosalpingo-contrast sonography was followed by STC, the concordance rate was 85%. When STC was followed by hysterosalpingo-contrast sonography, the concordance rate was 81%. In one patient the diagnosis of proximal occlusion of one tube as determined by hysterosalpingo-contrast sonography and STC had to be correlated in laparoscopy. In a patient, who after hysterosalpingo-contrast sonography and STC, was suspected to have bilateral proximal occlusion of the tubes, considerable bilateral proximal stenosis and distal occlusion was documented at laparoscopy. In conclusion, sonographically controlled STC may correct a misdiagnosis in cases where hysterosalpingo-contrast sonography leads to the finding of proximal tubal obstruction. The combination of hysterosalpingo-contrast sonography and STC as an out-patient investigation method for tubal patency assessment in infertile women avoids anaesthesia and radiation. For this reason we recommend the combination of sonographically controlled STC with hysterosalpingo-contrast sonography, at least in cases where proximal tubal occlusion is suspected after hysterosalpingo-contrast sonography. The influence of the order in which the two methods are used on the results of both should be investigated in a randomized study.     

Pathophysiology and endoscopic/balloon treatment of esophageal motility disorders

Diagnostic and therapeutic dilemmas associated with esophageal dysmotility syndromes continue to confront physicians managing these patient populations. Although modern manometric systems have allowed us to better define normal parameters of esophageal motility, with the exception of primary achalasia, the clinical relevance of many aberrant motor patterns remains unclear. The novel use of botulinum toxin in idiopathic achalasia stems from increased understanding of the pathogenesis of the disease. Similarly, as our knowledge of the pathophysiology of other esophageal motor disorders grows, in conjunction with improved diagnostic capabilities, more effective management strategies may be used in the future.     

Effect of graded exercise on esophageal motility and gastroesophageal reflux in nontrained subjects

The effects of graded exercise on esophageal motility and gastroesophageal reflux were evaluated in nine nontrained subjects, using a catheter with three strain-gauge transducers connected to a solid-state datalogger and an ambulatory intraesophageal pH monitor. Subjects exercised on a stationary bike at 45%, 60%, 75%, and 90% of peak O2 uptake (VO2 max). Durations of exercise sessions and rest periods varied among subjects. Studies were performed after an overnight fast and subjects received only intravenous infusion of 5% glucose solution during the study. Plasma concentrations of gastrin, motilin, glucagon, pancreatic polypeptide (PP), and vasoactive intestinal peptide (VIP) were determined at rest and before and after each exercise session. The duration, amplitude, and frequency of esophageal contractions declined with increasing exercise intensity, and the differences were significant (P < or = 0.05) for all three variables at 90% VO2 max. The number of gastroesophageal reflux episodes and the duration of esophageal acid exposure were significantly (P < or = 0.05) increased during exercise at 90% VO2 max. Plasma regulatory peptide concentrations showed no significant changes between rest and the various exercise sessions. Thus, exercise has profound effects on esophageal contractions and gastroesophageal reflux, which are intensity dependent. These effects were not mediated by the hormones measured. The results were similar to those observed in highly trained athletes, suggesting that the effects of exercise on esophageal function are similar in trained and nontrained subjects performing at similar percentages of VO2 max, even though the absolute levels of exercise achieved in each group are different.     

Correlation between esophageal motility and 24-hour pH recording in patients with gastroesophageal reflux

The relationship between manometric and pH-metric data was studied in a group of 50 patients with symptoms of gastroesophageal reflux. Using a multiple regression analysis, we found that the total percentage of reflux was significantly correlated to the infradiaphragmatic length and resting pressure of the lower esophageal sphincter and also to the mean amplitude of the contractile waves of the distal esophagus, thus revealing the important role of these factors in the antireflux mechanism. When the patients were divided into groups according to their manometric characteristics and the values of the various pH-metric parameters between these groups compared using a one-way analysis of variance, we found that the amplitude of the contractile waves and the percentage of deglutitions without response were related not only to the total percentage of reflux but also to the number of reflux episodes of greater than 5 min duration and to the duration of the longest episode. This shows that prolonged exposure of the esophageal mucosa to the refluxed material may be due, in part, to an alteration in the capacity for esophageal clearing.     

Laparoscopic Toupet fundoplication for gastroesophageal reflux disease with poor esophageal body motility

Impaired esophageal body motility is a complication of chronic gastroesophageal reflux disease (GERD). In patients with this disease, a 360-degree fundoplication may result in severe postoperative dysphagia. Forty-six patients with GERD who had a weak lower esophageal sphincter pressure and a positive acid reflux score associated with impaired esophageal body peristalsis in the distal esophagus (amplitude <30 mm Hg and >10% simultaneous or interrupted waves) were selected to undergo laparoscopic Toupet fundoplication. They were compared with 16 similar patients with poor esophageal body function who underwent Nissen fundoplication. The patients who underwent Toupet fundoplication had less dysphagia than those who had the Nissen procedure (9% vs.44%; P=0.0041). Twenty-four-hour ambulatory pH monitoring and esophageal manometry were repeated in 31 Toupet patients 6 months after surgery. Percentage of time of esophageal exposure to pH <4.0, DeMeester reflux score, lower esophageal pressure, intra-abdominal length, vector volume, and distal esophageal amplitude all improved significantly after surgery. Ninety-one percent of patients were free of reflux symptoms. The laparoscopic Toupet fundoplication provides an effective antireflux barrier according to manometric, pH, and symptom criteria. It avoids potential postoperative dysphagia in patients with weak esophageal peristalsis and results in improved esophageal body function 6 months after surgery.     

Neuronal control of motility changes in the canine lower esophageal sphincter and stomach in response to meal ingestion

BACKGROUND & AIMS: Neuronal control of motility changes in the lower esophageal sphincter (LES), gastric body (GB) and gastric antrum (GA) in response to meal ingestion is not fully understood. The aim of this study was to investigate the neuronal mechanism of the LES and gastric motility response to meal ingestion in conscious dogs. METHODS: Dogs fitted with force transducers in the LES, GB and GA were given neuronal antagonists before a meal. Motility was assessed for 10 min after feeding and was compared to results without antagonists. RESULTS: In the LES, atropine inhibited tonic contractions, whereas N omega-nitro-L-arginine (L-NAME) significantly enhanced tonic contractions initiated by meal ingestion. In the GB, atropine, hexamethonium or L-NAME inhibited receptive relaxation, and the effect of hexamethonium was significantly greater than that of atropine or L-NAME. In the GA, atropine, hexamethonium or naloxone inhibited postprandial phasic contractions, whereas L-NAME tended to enhance phasic contractions. CONCLUSIONS: Neuronal control of postprandial motility was clearly different in each region: (1) LES tonic contractions are mainly regulated by muscarinic receptors, (2) nicotinic transmission plays an essential role in receptive relaxation, which also involves muscarinic receptors and nitric oxide, (3) cholinergic nerves and opiate receptors are involved in the occurrence of antral phasic contractions, and (4) endogenous nitric oxide may inhibit postprandial contractions in the LES and GA.     

Intersubject variation of warfarin binding to protein in serum of normal subjects

The protein binding of warfarin was determined in the serum of 18 normal adult subjects (8 males and 10 females). A statistically significant negative correlation between free fraction of warfarin and albumin concentration was found. The free fraction of warfarin in the serum of women was significantly larger than that in the serum of men, apparently due to the lower albumin concentration in the serum of women.     

Sequential changes of esophageal motility after endoscopic injection sclerotherapy or variceal ligation for esophageal variceal bleeding: a scintigraphic study

OBJECTIVE: Endoscopic injection sclerotherapy and variceal ligation are two popular endoscopic methods used to treat esophageal variceal hemorrhage. These two methods have not been compared with regard to esophageal dysfunction after treatment. This is a prospective investigation of esophageal dysmotility after endoscopic injection sclerotherapy and variceal ligation. METHODS: Sequential changes of esophageal motility after endoscopic injection sclerotherapy (n = 25) and variceal ligation (n = 25) were investigated in 50 cirrhotic patients with recent variceal bleeding. Another 22 cirrhotics without esophageal varices were included as controls. Radionuclide esophageal transit tests were performed before initial endoscopic treatment, and 1 and 3 months after variceal eradication. RESULTS: The baseline esophageal transit time was longer in both the sclerotherapy (n = 25, 7.8 +/- 1.4 s) and ligation groups (n = 25, 8.2 +/- 1.8 s) than in controls (n = 22, 6.7 +/- 0.7 s, p < 0.005). The transit time was longer in patients with large varices than in those with small varices (8.3 +/- 1.7 vs. 7.2 +/- 0.7 s, p < 0.05). In the sclerotherapy group, the transit time was prolonged 1 month after variceal eradication, compared with its pretreatment state (n = 20, 7.6 +/- 1.5 vs. 10.0 +/- 2.2 s, p < 0.0001) but was shortened at 3 months compared with 1 month after variceal eradication (n = 12, 10.7 +/- 1.5 vs. 8.6 +/- 2.2 s, p < 0.05). Multiple regression analysis showed that the number of treatment sessions required to eradicate varices was the only significant factor associated with prolonged transit time (p < 0.05). In the ligation group, the transit time changed little at 1 month or 3 months after variceal eradication. CONCLUSIONS: Impairment of esophageal motility can be significant with endoscopic injection sclerotherapy but is reversible. However, endoscopic variceal ligation exerts no significant impact on esophageal motility.     

Engrailed and retinotectal topography

We examine the role of the Engrailed homeobox gene in establishment of local tectal topography. In the mesencephalon, a gradient of Engrailed appears early and defines the rostrocaudal axis of the tectum. Various experiments that cause ectopic Engrailed expression cause predictable readjustments of the retinotectal map. The newly discovered 'realisators' of the retinotopic map, such as receptor tyrosine kinase ligands ELF-1 and RAGS could be controlled directly by Engrailed. Indeed, recent results show that Engrailed regulates the expression of these ligands. The Engrailed gradient itself appears to be set up by signals including FGF8 and WNTI, allowing us to begin to trace the molecular cascade that is responsible for the correct wiring of the visual projection back into the early embryo.     

Effects of pentoxifylline on sperm motility and hyperactivated motility in vitro: a preliminary report

Previous reports (2, 3) have suggested that pentoxifylline increases sperm motility. In this preliminary report based on five asthenozoospermic and five normal motility semen samples, we were unable to demonstrate any statistically significant effect of pentoxifylline on percent motility of human spermatozoa. However, in vitro exposure to capacitation medium with pentoxifylline may lead to an increase in total hyperactivated motility in asthenozoospermic samples, an effect not evident in the normal motility samples in this study.     

Stomach motility and lyspafen

The effects of spermidine and spermine at varying concentrations upon the replicative ability of human fibroblasts in cell culture have been studied. The average concentrations of spermidine causing a 50% inhibition of prolifertion (ID50) after 3 days of growth for three normal cell strains and three strains derived from patients with cystic fibrosis (CF) were 4.4 X 10(-6) +/- 1.2 M and 6.2 X 10(-6) +/- 2.1 M, respectively. The values for spermine were 2.0 X 10(-6) +/- 0.5 M for normal and 2.2 X 10(-6) +/- 0.1 M for fibroblasts from cystic fibrosis patients. No significant difference between the replicative ability of normal and CF cell strains was seen over a wide range of polyamine concentrations employed for a period of up to 3 days.