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T Huber

Publications and source records attributed to T Huber.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Differences between women and men in the dipyridamole test. Symptomatic and electrocardiography findings in patients with coronary heart disease].

BACKGROUND: Problems are often encountered in evaluating the exercise stress ECG in women due to frequent false pathological findings. Besides the exercise ECG in the noninvasive diagnosis of coronary heart disease (CHD), the dipyridamole test is often used. As yet little is known about, whether a similarly high incidence of false positive test results occur under provocation with dipyridamole in women as in the exercise stress ECG. PATIENTS: In the present study the results of the dipyridamole test and of the coronary angiography in 218 patients, diagnosed as suspected of having CHD, were compared, especially allowing for specific sex differences. RESULTS: The prevalence of CHD in women was 17.8% and 56.1% in men. Under provocation with dipyridamole allowing for the indicator angina pectoris, the incidence of a false positive test results in relation to a significant coronary stenosis is higher in women with 80.5% than in men with 36.4% (p < 0.001). By contrast, men have a significantly higher rate of false negative test findings (40.9% to 11.1%; p < 0.001). Whereas the women obtained a sensitivity of 87.5%, the rating for men was 70.1%. Specificity was 21.6% for women and 48.7% for men. Test efficiency for men was 60.7% whereas for women 33.3% were calculated. The reaction of heart rate (significant increase of 33%) and systolic and diastolic blood pressure (no significant changes) did not reveal any relevant differences between men and women during the dipyridamole test. CONCLUSION: For patients with CHD similar diagnostic uncertainties occurred relating to specific sex differences in the results of the dipyridamole test, just like those known from the exercise ECG.

Adult↗
PubMed1994

Local elevation: a method for improving the searching properties of molecular dynamics simulation.

The concept of memory has been introduced into a molecular dynamics algorithm. This was done so as to persuade a molecular system to visit new areas of conformational space rather than be confined to a small number of low-energy regions. The method is demonstrated on a simple model system and the 11-residue cyclic peptide cyclosporin A. For comparison, calculations were also performed using simulated temperature annealing and a potential energy annealing scheme. Although the method can only be applied to systems with a small number of degrees of freedom, it offers the chance to generate a multitude of different low-energy structures, where other methods only give a single one or few. This is clearly important in problems such as drug design, where one is interested in the conformational spread of a system.

Algorithms↗
PubMed1994

Coupling constants again: experimental restraints in structure refinement.

Utilization of coupling constants as restraints in computational structure refinement is reviewed. In addition, we address the effect of conformational averaging and examine different approaches to apply the restraints when the experimental observable is obviously a result of averaging. Here, two different computational methods are compared. The simulation of a single structure with time-dependent restraints produces results very similar to those obtained with the calculation of numerous copies of the molecule (an ensemble of structures) and ensemble averaging. The advantages and disadvantages of the two methods are illustrated with simulations of cyclosporin A, for which 117 NOEs and 62 homo- and heteronuclear coupling constants have been measured.

Chemical Phenomena↗
PubMed1994

[Combined use of laparoscopic cholecystectomy and endoscopic retrograde cholangiography (ERC) and papillotomy (ERCP) in management of cholecysto-choledocholithiasis].

In a review of 328 cases the combination of laparoscopic cholecystectomy with specific use of endoscopic retrograde cholangiography (pre- and postoperatively) proved to be a riskless, secure and time-saving procedure. In our opinion this is a minimal invasive method of treatment for patients with cholecysto-/choledocholithiasis.

Adult↗
PubMed1993

[Molsidomine in chronic heart failure with liver congestion--oral or intravenous therapy?].

Patients suffering from congestive heart failure combined with gastrointestinal congestion often present irregular resorption and metabolism of orally applicated cardiovascular drugs. Intravenous therapy therefore is used very often for those patients. In this trial we compared the efficiency of molsidomine given either orally or intravenously in patients suffering from congestive heart failure. We investigated ten patients (54.6 +/- 13 years) with congestive heart failure (NYHA III and IV) and a central venous pressure > 10 mmHg. Five patients of group A were given 4 mg of molsidomine intravenously on the first day and an oral dose of 4 mg of molsidomine on the second day. The five patients of group B received the oral dose on the first day and intravenous treatment on the second day. Central venous pressure and plasma levels of molsidomine and of the effective metabolite SIN-1 were measured before as well as ten, 20, 40, 60 minutes, two, four and eight hours after application of molsidomine. Central venous pressure decreased significantly up to two hours after molsidomine in both oral and intravenous groups (p < or = 0.01). There was no relevant difference between the oral and the intravenous group. The hemodynamic parameters correlated with molsidomine plasma levels. According to our results the efficiency of oral molsidomine does not differ from intravenous molsidomine in patients with congestive heart failure.

Administration, Oral↗
PubMed1993

Structure refinement using time-averaged J-coupling constant restraints.

We describe a new penalty function for use in restrained molecular dynamics simulations which allows experimental J-coupling information to be enforced as a time-averaged, rather than instantaneous, quantity. The pseudo-energy term has been formulated in terms of a calculated J value (a measured quantity) rather than the relevant dihedral angle (a derived quantity). This accounts for the distinct non-linearity of the coupling constant with respect to either Cartesian coordinates or dihedral angles. Example simulations of the cyclic decapeptide antamanide show the procedure's ability to enforce experimental restraints while exploring a large region of conformational space and producing a relatively small disturbance of the physical force field.

Amino Acid Sequence↗
PubMed1993

Diaphragm disease of the ascending colon. Association with sustained-release diclofenac.

We describe the clinicopathological features of six patients, two with rheumatoid arthritis and four with osteoarthritis, in whom intake of sustained-release diclofenac for one or more years was associated with ulceration and or stricture of the ascending colon. All were referred for further evaluation of anemia and changes in bowel habits. Three had chronic watery diarrhea, one suffered from progressive constipation and subsequently needed a right hemicolectomy because of complete intestinal obstruction. In five patients, colonoscopy revealed single to multiple semilunar ulcers, predominantly localized on the crest of the haustra of the ascending colon. In five of six cases the lumen was narrowed, from slight accentuation of the haustrum to almost pinhole-like concentric stenosis. All except one patient had multiple diaphragm-like strictures. The macroscopic and microscopic appearances closely resembled those of similar lesions previously described in the terminal ileum in patients treated with nonsteroidal anti-inflammatory drugs. It appears that the slow-release form of a nonsteroidal anti-inflammatory drug, such as sustained-release diclofenac, predisposes to manifestations of such lesions in the ascending colon.

Aged↗
PubMed1993

Lymphoid cells in afferent and efferent intestinal lymph: lymphocyte subpopulations and cell migration.

Gut wall emigrating cells have been characterized in the intestinal lymph. The intestinal lymph duct was cannulated in 6-month-old minipigs. Under non-restraining conditions the efferent lymph from the mesenteric lymph nodes was collected in seven normal animals. Lymph coming directly from the gut (afferent lymph) was also collected in 18 pigs after resection of the mesenteric lymph node chains 3 months previously. The intestinal lymph flow was similar in both groups (around 18 ml/h). The lymphoid cell yield was 1.2 +/- 1.0 x 10(6)/h in control animals, while in mesenteric lymph node resected pigs it was around 20 times higher (26.2 +/- 17.6 x 10(6)/h). In the gut-derived lymph 76.5 +/- 8.8% T lymphocytes were observed (CD4+, 48.1 +/- 15.5%; CD8+, 53.6 +/- 12.7%). The percentage of immunoglobulin-positive cells was lower (IgM+, 10.1 +/- 4.5; IgA+, 1.7 +/- 1.1). In 14 mesenteric lymph node resected pigs a mean of 5.6 +/- 3.1 x 10(8) lymphocytes from the gut lymph were labelled in vitro with a fluorescent dye and retransfused. The labelling index of fluorescent cells in the intestinal lymph increased rapidly and remained at a high level until 44 h after cell transfusion. A four-to-ten times lower labelling index was found in the spleen, various lymph nodes and Peyer's patches. Most of the recovered lymphocytes were T cells. This model provides access to the cell pool leaving the gut wall, thus allowing an examination of its role in the gastrointestinal tract and other mucosal-lined organs.

Animals↗
PubMed1993

Effects of ranitidine and cisapride on acid reflux and oesophageal motility in patients with reflux oesophagitis: a 24 hour ambulatory combined pH and manometry study.

The effect of ranitidine and cisapride on acid reflux and oesophageal motility was investigated in 18 patients with endoscopically verified erosive reflux oesophagitis. Each patient was treated with placebo, ranitidine (150 mg twice daily), and ranitidine (150 mg twice daily) plus cisapride (20 mg twice daily) in a double blind, double dummy, within subject, three way cross over design. Oesophageal acidity and motility were monitored under ambulatory conditions for 24 hours on the fourth day of treatment, after a wash out period of 10 days during which patients received only antacids for relief of symptoms. Acid reflux was monitored by a pH electrode located 5 cm above the lower oesophageal sphincter. Intraoesophageal pressure was simultaneously recorded from four transducers placed 20, 15, 10, and 5 cm above the lower oesophageal sphincter. Upright reflux was three times higher than supine reflux (median (range) 13.3 (3.7-35.0)% v 3.7 (0-37.6)% of the time with pH < 4.0, p < 0.01, n = 18). Compared with placebo, ranitidine decreased total reflux (from 10.0 (3.2-32.6)% to 6.4 (1.2-22.9)%, p < 0.01), upright reflux (p < 0.05), supine reflux (p < 0.001), and postprandial reflux (p < 0.01), but did not affect oesophageal motility. The combination of ranitidine with cisapride further diminished the acid reflux found with ranitidine--that is, cisapride led to an additional reduction of total reflux (from 6.4 (1.2-22.9)% to 3.7 (1.0-12.7)%, p < 0.01), supine reflux (p < 0.05), and postprandial reflux (p < 0.05). Cisapride also reduced both the number (p<0.01) and duration (p<0.05) of reflux episodes and significantly increased amplitude, duration, and propagation velocity of oesophageal contractions (p<0.05) but did not affect the number of contractions. The findings show that the 30% reduction of oesophageal acid exposure achieved by a conventional dose of ranitidine (150 mg twice daily) can be improved to more than 60% by combination with cisapride (20 mg twice daily). The cisapride induced increase in oesophageal contractile force and propagation velocity seems to enhance the clearance of gastro-oesophageal reflux. Combination of a histamine H2 receptor antagonist with a prokinetic agent may therefore provide an alternative treatment for reflux oesophagitis.

Adult↗
PubMed1993

Transdermal nicotine in smoking cessation and involvement of non-specific influences.

The efficacy of a nicotine transdermal therapeutic system (TTS) (available size 10, 20 and 30 cm2; nicotine delivery rate = 0.7 mg/cm2/24 h) as an aid for smoking cessation, was evaluated in a randomized, single-blind, placebo-controlled, monocenter study using 160 heavy-smokers (> 20 cigarettes/day), male and female, who were divided into two matched parallel groups. The nicotine replacement treatment lasted for 3 months and was carried out according to the manufacturers recommendations. Abstinence was defined as smoking no cigarette during the last week of each month and COHb-levels < or = 1.2%. Efficacy was assessed using abstinence rates, withdrawal symptoms and cigarette consumption. Although at the commencement of the study all subjects expressed a high motivation to stop smoking, about a third were lost to follow-up at 4 weeks. This was attributed mainly to the lack of counselling and group dynamics. The greatest effect on smoking cessation and cigarette consumption was attributable to a non-specific aspect of treatment, i.e. the motivation to stop smoking on application of the first patch. On an intention-to-treat basis (all subjects), abstinence rates were 24% and 18% after 1 month, 24% and 14% after 2 months and 14% and 6% after 3 months for the nicotine-TTS and placebo-TTS, respectively. Nicotine-TTS was at least twice as effective as placebo in maintaining nicotine abstinence. The superiority of the nicotine-TTS was supported by the trend to a higher craving-for-cigarettes score and significantly higher blood COHb and cigarette consumption in the non-abstainers treated with placebo.

Administration, Cutaneous↗
PubMed1992

[Ventilatory changes during laparoscopic cholecystectomy].

During the past 2 years in Europe and the USA laparoscopic cholecystectomy (LC) has become a widely practiced procedure. Nevertheless, the effects of long-lasting laparoscopic procedures on carbon dioxide elimination have not yet been systematically investigated. METHODS. Approval from the institutional research review board was obtained, as was written informed consent from the patients. Eleven patients undergoing LC were studied. Patient age ranged from 31 to 67 years. All patients received total intravenous anaesthesia (fentanyl, propofol, vecuronium, DHB). Controlled ventilation with a tidal volume of 12-14 ml/kg was administered. Before introduction of anaesthesia a cannula was inserted into the left radial artery. Blood gas analysis was undertaken just before introduction, just before insufflation of carbon dioxide, and thereafter at two intervals, after reaching an intra-abdominal pressure of 12 mm Hg, 15 min apart. Oxygen consumption and carbon dioxide output were measured using a calorimeter (Deltatrac TM, Datex). Intra-abdominal pressure was maintained at 12 mm Hg during the operation. RESULTS. After onset of the pneumoperitoneum inspiratory peak and plateau pressure showed an increase by more than 40%. During the operation respiratory minute volume had to be increased by about 30-40% to maintain normocapnia. Oxygen consumption remained nearly unchanged during the procedure while carbon dioxide output increased up to 38% 60 min after onset of the pneumoperitoneum. D(a-A) CO2 showed no significant change, indicating no increase in dead space. Beginning with the insufflation there was a significant increase in mean arterial pressure that lasted until the end of the procedure. CONCLUSION. The described effects of carbon dioxide insufflation, especially the extent of carbon dioxide resorption, define the need for careful monitoring of respiratory function during LC, especially in patients with preexisting cardiopulmonary disease.

Adult↗
PubMed1992

[Symptomatic cholecystolithiasis: 1992 therapy options].

Modern treatment of symptomatic cholecystolithiasis requires a knowledge of several nonsurgical and surgical treatment options. Extracorporeal shock-wave lithotripsy and oral bile acid therapy offer the possibilities of noninvasive, outpatient treatment in approximately 20% of all symptomatic gallstone patients at a low complication rate. The percutaneous interventional techniques such as contact dissolution by means of ether or mechanical stone removal may in principle be used in a higher percentage of patients but are considerably more invasive. None of the nonsurgical techniques can exclude the relative risk of gallstone recurrence. Laparoscopic cholecystectomy constitutes a major progress in the surgical treatment of gallstone disease, since it is much less invasive than conventional cholecystectomy and requires a much shorter hospital stay and recovery time. The laparoscopic technique is primarily indicated in patients with symptomatic, uncomplicated cholecystolithiasis. Nevertheless, the range of indications is expanding as experience with this technique increases. Under certain circumstances, laparoscopic cholecystectomy is already being combined with endoscopic sphincterotomy in the presence of bile duct calculi. Conventional cholecystectomy remains the treatment of choice for complicated cases.

Bile Acids and Salts↗
PubMed1991

Prescription of drugs not listed in a clinic's pharmacopoeia: supervision by clinical pharmacologists.

The pharmaceutical market in the FRG offers about 11,000 different preparations and formulations. A restricted list (pharmacopoeia) containing approximately 1,000 drugs has been proved to cover the routine requirements of a university clinic and most of the additional drugs demanded by the physicians as 'exceptis excipiendis'. Restrictive control of requests for drugs not included in the internal pharmacopoeia by clinical pharmacologists has reduced the absolute number of requests by half, and about 60% of the remaining requests could be replaced by drugs listed in the pharmacopoeia. The majority of the special requests arose from the continuation of drugs presented to out-patients by the resident physicians after admission of the patient to the hospital. The supervision may lead to more critical revision of out-patient medication, but a substantial reduction of drug expenditure was not attained, as the drugs requested amounted only to a minor fraction of the overall drug expenditure by the hospital.

Drug Prescriptions↗