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Effects of antidepressants on the exploration, spontaneous motor activity and isolation-induced aggressiveness in mice.

OBJECTIVE: To study the role of different antidepressants on exploration, spontaneous motor activity and isolation-induced aggressiveness in mice, further to discuss different mechanisms of their anti-aggression. METHODS: With an aggressive model induced by isolation housing in mice, antagonism of different antidepressants against isolation-induced aggression was evaluated. In the group-housed mice given the same treatment as aggressive test, exploration and spontaneous motor activity were measured. RESULTS: (1) Mianserin (0.5-5 mg/kg-1), buspirone (2.5-10 mg.kg-1) and meclobemide (2.5-10 mg.kg-1) significantly inhibited the exploration in the group-housed mice, but not fluoxetine (2.5-10 mg.kg-1), imipramine (2.5-10 mg.kg-1) and DOI (0.5-2 mg.kg-1); (2) Both mianserin and buspirone, but not fluoxetine, imipramine, meclobemide and DOI, obviously reduced spontaneous motor activity; (3) Fluoxetine, miaserin, imipramine and buspirone significantly and dose-dependently antagonized isolation-induced aggressive behavior, whereas meclobemide failed to attenuate aggression. DOI dual-regulated aggressiveness in isolation mice. CONCLUSION: Our findings suggest that the effects of fluoxetine, mianserin, buspirone, imipramine, meclobemide and DOI on exploration, spontaneous motor activity and isolation-induced aggression in mice are different, which may involve different pharmacological mechanisms underlying their anti-aggression in isolation mice. 5-HT1A and 5-HT2A/2C receptors may mediate isolation-induced aggressive behavior in mice. The involvement of 5-HT receptor subtypes needs further clarification.

Aggression↗

[Primary suture following the bile duct exploration in cholelithiasis].

Classical performance of bile duct exploration is always strictly connected with the problem of an incised bile duct closure. In majority of surgical centers an external T-tube drainage was carried out in last century. But is an external drainage the best method to be used? The aim of the paper was to establish criteria for including (or excluding) patients to groups undergoing primary suture of bile duct. The comparison of the patients in whom bile duct exploration was followed by primary suture with the group in which T-tube was left in bile duct lumen was performed. Recently in our Department a classical method has been used to operate on 65 patients with cholelithiasis. In 42 patients a preoperatively planned bile duct exploration has been performed. In 14 patients a T-tube was left after the exploration, in 24 patients bile duct was closed with a primary suture. In other 18 patients with residual and recurrent bile duct stones T-tube was left in bile duct only in two patients. Based on literature analysis, our observations, and surgical experience criteria for including and excluding patients for primary suture of bile duct have been established. Groups of patients with and without T-tube were compared, considering complications and economic aspects of hospitalization. Our opinion is that whenever in specialized surgical centers detailed criteria are established and followed precisely, primary bile duct closure is a simple and safe procedure, responsible for few complications. The cost of hospitalization in the case of primary suture is half as much as the price of the hospitalization in the case of T-tube.

Adult↗

[Exploration of the otolith function].

The analysis of our vertiginous patients reveals that the likely existence of a pattern of symptoms related to a disturbance of the otolith organ responsible for detection of linear accelerations. Very often otolith pathology affects only certain directions of movement or tilting in relation to gravity. The various tests of the otolith function do not seem to identify all of these otolith deficits. It is possible that each individual test explores only partially the 4 otolith organs. Our otolith tests are still either too general, or, only focused on a part of a multi-directional function (and wrongly emphasizing a partial pathology). Thus, the history remains the finest diagnostic tool. The exploration of the otolith function has improved. These tests are not redundant. The subjective visual vertical tests the otolith function up to the vestibular cortex whilst the off-vertical axis rotation (OVAR) test explores the ocular otolith reflex. The myogenic otolith evoked potentials are saccule-collic. The cerebral cartography shows the various zones of cortical saccular activity and the tilt suppression test explores a reflex involving the cerebellar nodulus. However all of these tests are still nonspecific. There 'non-specificity' is similar to the non-specific nature of a free field hearing or the rotatory vestibular tests. The analysis of patient symptoms, using diagrams summarizing the principal clinical findings, or using a 3D software, facilitates the identification of the involved side, the affected organ (utricle or saccule) and to some extent the possible site of the lesion (just as a visual field would assist in identification of the retinal area affected prior to fundoscopy). Some otolith tests can be very sensitive albeit non-specific like the subjective visual vertical test. Others are more specific in identification of the organ and side affected like the otolith sacculo-collic evoked potentials. The choice of vestibular function tests is best based on the patient's particular symptoms. Thus a patient complaining of falling outwards is to be tested by offset rotations. A patient complaining of falling while going down in a lift is best investigated by the cortical vestibular otolith evoked potentials.

Humans↗

Pre-operative dynamic interactive exploration of complex articular fractures using a novel 3D navigation tool.

OBJECTIVES: Trauma surgeons possess specific anticipative pathoanatomical and procedural domain knowledge that can be used for information extraction from original CT image data. This knowledge so far remains unused in clinical workflow and surgeons do not take an active part in the process of image generation and processing. The objectives of our work are to propose and employ a strategy to directly involve surgeons in a dynamic image exploration process and to exemplarily assess the clinical use of this approach for pre-operative diagnosis of complex articular fractures. METHODS: We used an interactive 3D navigation tool with a novel human-computer interface for the exploration of articular fractures of two selected anatomical structures. The system offers dynamic interaction with a virtual 3D reconstruction model and the possibility to create on-the-fly oblique multiplanar reformations by tracking hand movements. Three expert surgeons performed exemplary explorations and rated the use of the method for preoperative diagnosis in informal interviews. RESULTS: The approach and the system were well received by the three surgeons. The dynamic interaction was rated to be helpful in understanding fracture morphology. Two examples--a radius and a calcaneal fracture--are presented. CONCLUSIONS: Surgeons with their specific domain knowledge should be involved in the process of image processing. The benefit of using oblique multiplanar reformations for pre-operative planning in articular fractures appears to be substantial and they should therefore be included in radiological and surgical textbooks. Further evaluation is necessary to assess the use of interactive exploration systems in routine diagnosis.

Feasibility Studies↗

Assessing the role of routine choledochoscopy during exploration of the bile duct.

Two hundred and five consecutive explorations of the common bile duct were evaluated to assess the value of routine choledoschoscopic examination in preventing retained stones. Conventional exploration was performed in 139 instances (group 1), while routine choledochoscopy was added in 66 procedures (group 2). Preoperative temperature, leukocyte count, total bilirubin, amylase and alkaline phosphatase levels were not significantly different between the groups. Nine retained stones were demonstrated by postoperative cholangiography among the patients in group 1 as compared with three retained stones noted in those in group 2. This difference was not significant. Postoperative mortality and complication rates were unaffected by the performance of an endoscopic study of the biliary tract during ductal exploration. Choledochoscopy added an average of 36 minutes to the duration of the operative procedure (p less than 0.001). Choledochoscopy may prove helpful in selected instances, but the current data do not support its routine use during exploration of the common bile duct.

Cholangiography↗

Combined supraduodenal and transduodenal exploration of the common bile duct with sphincterotomy.

From a consecutive series of 2,221 cholecystectomies, 177 patients underwent combined supraduodenal and transduodenal exploration of the common bile duct and 390 were treated by supraduodenal exploration alone. The mortality rate after both exploration procedures was the same (2.8 per cent). However, two patients died of septic complications associated with duodenal fistulas in the combined exploration group. Five patients had retained stones in the common bile duct which subsequently flushed out with a saline solution irrigation administered through the T tube in three patients and the stone passed spontaneously in one patient. Clinically significant and biochemically documented acute pancreatitis occurred in five patients, one of whom died. Four patients had postoperative cholangitis develop which responded to antibiotic therapy. We are not aware of any patient who had common bile duct stones, chronic pancreatitis or ampullary stenosis after the combined procedure at follow-up study of between six months and 13 years.

Aged↗

[How to explore the microangiopathy of collagen diseases].

Numerous methods for the exploration of the microangiopathy of collagen disease exist, but their perspective differs as a function of their use to assist early diagnosis, to establish a prognosis, to provide follow-up data or to attempt better understanding of the mechanism of these affections. Progressive systemic sclerosis is a very suitable collagen disease with which to illustrate these methods, since in this affection the microangiopathy is frequent, diffuse, of early onset and also formally implicated in the pathogenic rank. Biopsy specimens provide details of morphologic anomalies of the microcirculation. Capillary changes have been demonstrated in muscle and the choroid but in clinical practice histology samples involve mainly the digital pulp, subungual fold and accessory salivary glands. Isotopic and fluorescent angiography are, on the contrary, in vivo methods for dynamic exploration of skin microcirculation, but the invasive nature of these methods is an obstacle to their repetition in a same patient and to follow-up of the microangiopathy. Non-invasive vascular explorations avoid this pitfall. Thermometry, thermography, digital plethysmography under hot and cold conditions, videomicroscopy of the nailbed, percutaneous PO2 and laser-doppler tests measure functional parameters, the hemodynamic significance of which require discussion. Capillaroscopy, mainly oriented towards the study of capillary morphologic changes, also allows, together with plethysmography, measurement of digital systolic pressure. Exploration of the microangiopathy of collagen disease requires a judicious combination of currently available morphologic and functional techniques which, far from being superimposable are on the contrary complementary.

Capillaries↗

The effect of active versus passive exploration on memory for spatial location in children.

The effect of active exploration upon memory for spatial location of an event was assessed for children at 2 age levels. Each child took a walk through the same unfamiliar hallway in search of a hidden object which he was later asked to relocate. Half the children were accompanied by an adult holding their hand (passive condition), while the other half proceeded on their own with an adult following behind (active condition). An age x condition interaction revealed that active exploration significantly improved performance of the 3- and 4-year-old group while not affecting the performance of the 9- and 10-year-olds. The 3- and 4-year-olds in the active condition, however, were still significantly less accurate than the older children, despite their experience of self-directed exploration. The results are interpreted as supporting the hypothesis that self-directed activity serves to increase attention of preoperational children to relevant topological cues in the environment, whereas concrete operational children, due to their knowledge of projective and Euclidean space, demonstrate increased capacity to efficiently encode spatial information regardless of the mode of exploration.

Child↗

Explorative statistical analysis and the valuation of hypotheses.

Clinical research has to include data from various sources. In many cases, the structure of the data allows explorative analysis only. This paper is concerned with situations in which no special hypotheses from a large set of possible ones have been predetermined for statistical testing or wherein tests are planned for hypotheses on only very few variables out of a high dimensional response as in controlled clinical trials. Explorative analysis of those experiments frequently uses p-values for the valuation of the hypotheses not designated for testing. It is shown by means of an example to what extent conclusions may be wrong if they result from ignoring (or misunderstanding) the explorative character of such p-values. Posterior probabilities with respect to suitable priors are proposed as an alternative explorative method for the valuation of hypotheses. The advantages of this procedure are discussed.

Research↗

[The regional exploration of pulmonary function using xenon 133. Value of the gamma camera connected to a computer (author's transl)].

Regional isotopic exploration of ventilation and pulmonary perfusion is not yet widely applied in clinical practice, by virtue of the complexity of the equipment required, but also because of the complicated and lengthy analysis of the results. In this respect, connection of the scintillation camera to a computer represents a major advance which other authors have already emphasized. Our own experience in this area and our method of exploration are described. The results of regional exploration in a group of 43 cases of chronic obstructive lung disease (33 patients of the chronic bronchitis type, 10 patients with emphysema) are analysed and discussed. The results indicate the following : in chronic bronchitis, a very marked fall in ventilation of the bases with inversion of the normal vertical ventilation gradient, and a fall in the ventilation/perfusion ratio of the bases; in emphysema, a fall in ventilation, but also and above all in regional perfusion of all territories with preservation of normal or even increased regional ventilation/perfusion ratios. Regional exploration may also be of value in the detection of early stages of obstructive lung disease, and in pre-operative assessment in thoracic surgery.

Bronchitis↗

Operative cholangiomanometry as a guide to common duct exploration.

A trial of operative cholangiomanometry was proposed as a guide to common duct exploration to see if this technique would help in reducing the incidence of unnecessary common bile duct explorations and the incidence of retained stones. The technique for operative cholangiomanometry as modified from White is described. This method was used in 21 patients. A very close correlation between manometry and cholangiography in predicting the presence of pathology within the common duct at the time of extrahepatic biliary surgery was shown. Flow was the most accurate diagnostic parameter. Seven patients who were found to have common duct stones had both abnormal manometry and cholangiography. Fourteen patients without stones included 12 with negative cholangiography and manometry, and two in which manometry was normal but cholangiography suggested pathology. Common duct manometry and cholangiography can be used to decrease the number of unnecessary common duct explorations and the incidence of retained stones. The theory that common duct pathology will increase pressure and decrease flow rates is supported by this study. Manometry and cholangiography should be used in combination as they are additive studies. Criteria for deciding when to explore the common duct are presented.

Adult↗

In vitro studies of the effect of a dental explorer on the formation of an artificial carious lesion.

This project deals with in vitro mechanical damage of early carious lesion (enamel lesion) in artificial U-shaped grooves caused by a sharp dental explorer. The lesions were formed in enamel grooves in 3 percent by weight cellulose solution in 0.1 M lactic acid containing 1.08 M KH2PO4 and 1.8 mM CaCl2 buffer to pH 4.28 after two weeks of demineralization. A relatively intact surface layer was observed in all the grooves. Three demineralized grooves were probed with different forces 100 g, 300 g and 500 g. The traumatic damage was assessed by using microradiography. There was no damaging effect in the sound enamel grooves probed with a sharp explorer up to a force of 500 g. Breakdown of the surface layer was assessed in all probed demineralized enamel grooves, converting the white spot lesion with apparently a sound surface layer into a cavity. Explorer penetration into the lesion was found to be strongly related to the force applied. The use of a sharp dental explorer should be reconsidered in examination and diagnosis of early carious lesions in pits and fissures and an alternative technique should be sought.

Dental Caries↗

Exploration of the common bile duct for stones: the influence of the flexible choledochoscope and perioperative antibiotic prophylaxis.

A retrospective study of 110 patients, out of a total of 743 open cholecystectomies, who have undergone common bile duct (CBD) exploration for stones between 1985 and 1990. CBD exploration was performed in the presence of abnormal peroperative cholangiogram in 86 (78%) patients. The remaining 24 patients were known to have either an abnormal preoperative ERCP or palpable ductal stones at the time of surgery. Post exploratory choledochoscopy was performed as an additional completion procedure in 58 (53%) patients and it identified further stones in 28 (48.3%) of these patients. There were three patients in whom no stones were identified on exploration of the CBD. Documented evidence of peroperative antibiotic prophylaxis was obtained in 78 (71%) patients. A total of 27 (24.5%) patients developed complications including seven (6.4%) patients with retained stones. In four of these patients with retained stones, flexible choledochoscopy was undertaken as an additional completion procedure to ensure ductal clearance. Cardiorespiratory and septic complications were the next most common problems occurring in 6.5% and 5.4% respectively, of patients reviewed. In conclusion, the retained stone rate has fallen from 14% in 1987 to 6.4% in this study. The choledochoscope has influenced this as it identified further residual stones following conventional exploration. The sepsis rate has also fallen from 19.5% to 4.5% in this study. We believe this is due to the use of antibiotic prophylaxis.

Adult↗

The pediatric inguinal hernia: is contralateral exploration justified?

To determine if contralateral inguinal hernia exploration is justified we decided to study our experience with 161 consecutive cases who underwent bilateral repair during a 30 months period. 61% of the population were infants younger than two years of age, and 19% premature babies. 69 pts presented with an RIH, 47 with an LIH and 45 pts with BIH. 16% suffered an episode of preoperative incarceration which were all reduced satisfactorily and operated promptly. A positive contralateral finding (either a hernial sac or a patent processus vaginalis) was identified in 74% RIH and 72% LIH patients upon exploration. No incidence of testicular edema/atrophy, vas deferens injury, or recurrence was reported in the six-year follow-up of the study. Statistical analysis of the contralateral findings during surgery with sex, gestational age and age at operation showed that females and infants younger than two months of age had a higher probability of having positive findings. We could not show that prematurity or left-sided hernias were associated with a higher positive contralateral rate. The major benefit of contralateral exploration is based on the fact that it allows discovery and elimination of a patent processus vaginalis so a hernia cannot develop subsequently. We conclude by establishing certain criteria that justifies the routine contralateral exploration of the pediatric hernia: the surgeon should be experienced in child care, associated conditions should not increase the surgical risks significantly, time-consuming dissections of the cord structures should be discouraged, and the operating time should be kept to a minimum.

Child↗

Parathyroid re-exploration in patients with primary hyperparathyroidism.

In a prospective study fifteen consecutive patients underwent re-exploration for persistent or recurrent primary hyperparathyroidism. We aimed at definite preoperative localization of enlarged, abnormal parathyroid glands in all patients. Ultrasound guided fine needle aspirations for parathyroid hormone assay had the highest accuracy rate of 100%, those for cervical ultrasound and thallium-technetium, scintigraphy were similar, both 86%. Normocalcaemia was achieved in all patients, but five (33%) patients required more than one re-exploration. Permanent unilateral vocal cord injury occurred in two (13%) patients, but none had permanent hypocalcaemia. We conclude that the results of re-exploration are good but one third of the patients required more than one reoperation. Localization studies aiming at definite localization are mandatory before re-exploration. On the basis of our results we suggest a protocol for preoperative localization which takes into consideration both the accuracy rates and the costs of localization examinations.

Adenoma↗

[Radiological exploration of the thorax. Strategy and indications].

The widespread use of computed tomography and the advent of magnetic resonance imagery have considerably modified the methods and strategies of thoracic exploration over the last 10 years. Standard radiography remains the first-line examination for all thoracic diseases, and often is the only imagery required; further explorations are indicated on the basis of the information seen on standard films. Computed tomography has become an essential element in the work-up of all diseases involving a tumoural process in the lung. It is also indicated in bronchiestasis and for the exploration of chronic lung diseases. Further information may be obtained with magnetic resonance imagery. Although this method cannot be used to explore the pulmonary parenchyma, it is particularly adapted in cases involving the pleura, mediastinum (tumours and vessels) and the thoracic wall. Scintigraphy is mainly used to detect pulmonary migrations and to investigate lung function before thoracic surgery. Pulmonary angiography remains the reference imagery for the diagnosis of pulmonary embolism but has lost its other indications. Tomobronchography is exceptionally required. Current strategy in infectious diseases is to always begin with standard radiography, then to complete the work-up with further examinations only when necessary. Correct evaluation of tumoural processes relies heavily on tomography even for very small masses since it provides essential information on localization and extension. Management of primary bronchogenic cancers also requires repeated tomographic studies. Magnetic resonance images are indicated on the basis of the tomography results and are particularly useful in tumours of the apex and extension to the spinal column or mediastinum. For chronic bronchopathy, pulmonary scintigraphy is performed after standard films in the preoperative work-up then is sometimes completed with other techniques. In cases of suspected pulmonary emboli, a normal scintigraphy can eliminate the diagnosis. Inversely, certain teams propose coupling perfusion scintigraphy with ventilation scintigraphy to detect mismatches, particularly distinctive signs of pulmonary emboli. When the diagnosis remains uncertain, pulmonary angiography is the reference imagery technique.

Angiography↗

An experimental model for laparoscopic common bile duct exploration.

The development of an effective and reliable technique for laparoscopic common bile duct exploration has been limited by the technical difficulty of the procedure and the lack of a suitable animal model with a bile duct diameter large enough to accommodate the fiberoptic choledochoscope and other instruments used for stone extraction. Short-term bile duct ligation in the dog provides a simple and reproducible animal model that enables the surgeon to gain experience with laparoscopic common bile duct exploration in a laboratory setting. This model will enable the surgeon to develop the technical skills necessary to perform laparoscopic common bile duct exploration. In addition, the model may facilitate the development and refinement of new techniques and instruments that will facilitate laparoscopic common bile duct exploration in the clinical setting.

Animals↗

Simultaneous thyroid operation in patients undergoing initial neck exploration for primary hyperparathyroidism.

Twenty-three (25%) out of 92 patients undergoing initial neck exploration for primary hyperparathyroidism (PHPT) also underwent a simultaneous thyroid operation. Based on a postoperative analysis a simultaneous thyroid operation was unquestionably indicated in 18 (78%) cases but in the remaining five (18%) the indications were less well proved. Six (9%) of the 66 patients subjected only to neck exploration for PHPT and four (17%) of those with a simultaneous thyroid operation had postoperative complications (P > 0.05). The patients with four incidental biopsies and an incidental lobectomy had no complications, but otherwise complications were evenly distributed among the different thyroid operations. The somewhat higher complication rate in patients undergoing simultaneous thyroid operation was related to the learning curve of the surgeon. Simultaneous thyroid operation increased the operating room costs only by 31%, and the combined operation was definitely cost effective as compared with separate parathyroid and thyroid operations. It is concluded that in experienced hands, simultaneous thyroid operation is safe, cost effective and recommendable for patients undergoing initial neck exploration for PHPT, because it avoids the expense and risk associated with neck re-exploration and can reveal unsuspected cancer.

Adult↗