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At least 955 records · Page 53Linked to original sources
PubMed1996

Ropivacaine gel in active distal ulcerative colitis and proctitis -- a pharmacokinetic and exploratory clinical study.

BACKGROUND: Local anaesthetics have anti-inflammatory effects as indicated by preclinical and explorative clinical data. OBJECTIVE: To investigate the pharmacokinetics, tolerability and clinical efficacy of the new local anaesthetic ropivacaine in active distal ulcerative colitis. METHODS: Twelve patients were openly given 200 mg ropivacaine gel rectally twice daily for 2 weeks in this open study. RESULTS: Mean peak total plasma concentrations, Cmax, were 1.37, 1.26, 1.03 and 0.99 mg/L on treatment days 1, 3, 7 and 14. The mean unbound plasma concentrations at Cmax were 0.071, 0.058, 0.050 and 0.045 mg/L. The decrease in Cmax (P < 0.01) as well as in the area under the plasma concentration-time curve, AUC (P < 0.01), may be due to a decreased absorption but an increased metabolism cannot be excluded. The median time of Cmax was around 2 h and the mean terminal half-life was around 2.7 h. Mucosal inflammation assessed endoscopically at the most severely affected site decreased after 2 weeks of treatment (P < 0.01; blinded) and there was also a trend towards histological improvement (P = 0.06). Clinical symptoms, including total number of stools, blood in stools and diarrhoea increased (P < 0.05) during the study. The treatment was, in general, well tolerated with few gastrointestinal complaints and there were no unequivocal signs of systemic effects. CONCLUSIONS: Ropivacaine given rectally as a gel, 200 mg twice daily does not accumulate over a 2-week treatment period and carries a low risk for systemic adverse effects. The results suggest a therapeutic efficacy in active distal ulcerative colitis.

Administration, Rectal↗
PubMed1988

[The effect of exogenous factors on pre-cecal nutrient and amino acid resorption determined in swine with ileo-rectal anastomoses. 2. The effect of the degree of grinding of plant protein-rich concentrates in rations].

In digestion trials using pigs fitted with ileo-rectal anastomoses and intact pigs, the influence of two different grinding finenesses (coarse, fine) of vegetable high-protein concentrates (soya bean meal, field bean, lupin) added to cereal diets was examined. It was found that neither the precaecal nor the total nutrient absorption and digestibility were practically injured, when in the concentrates the particle sizes bigger than 2 mm did not amount more than 20% and whole grains hardly occurred. The investigations concerned the crude putrients, watersoluble carbohydrates and starch as well as the indispensable and dispensable amino acids. The apparent and true precaecal absorption values and total digestibility data for soya bean meal (heat treated), field bean (variety 'Fribo' and yellow sweet lupin (variety 'Bornova'--calculated by the different method--are given and discussed.

Animal Feed↗
PubMed1986

Effect of administration route on the selective lymphatic delivery of cyclosporin A by lipid-surfactant mixed micelles.

The absorption and lymphatic delivery of a new immunosuppressive drug, cyclosporin A (CsA), with the aid of lipid surfactant mixed micelles (MM) system using different administration routes were studied in the thoracic duct cannulated rat model at a dose level of 7 mg/kg. The rectal or intraperitoneal (i.p.) administration of CsA indicated a small amount of CsA in the plasma and in the lymph for 6 h. As oral routes, intrastomach (i.s.) and intraduodenal (i.d.) administration of CsA were performed and high lymph CsA levels were obtained. The i.s. administration of CsA resulted in the highest CsA levels in the lymph, 16 micrograms/ml, about twenty times higher than the rectal or i.p. administration. These results strongly support the usefulness of an oral CsA dosage form for the selective lymphatic delivery of CsA in clinical immunosuppressive therapy by means of a new mixed micelles system.

Administration, Oral↗
PubMed1988

[Support and suspension of the pelvic viscera in women. Functional and surgical anatomy].

This work is an attempt to settle the semantics of the pelvic connective tissues based on the international nomenclature (Nomina Anatomica) on the one hand on the other following a study of the macroscopic anatomy together with the microscopic appearances and a functional study together with a radiological study which includes in particular tomodensitometry. The Pelvic viscera are held in position by visceral fasciae which are continuous with the parietal pelvic fascia and the retro peritoneal connective tissue. This connective tissue, which is moderately loose, is arranged around the blood vessels as visceral ligaments. These are more obvious when traction is exerted during surgical operations and it resembles the way strands of a net come together when they are being stretched. It is essential to ligate and cut these ligaments if the viscera are to be freed. The surfaces which join the viscera together (the septum and the retro-pubic and retro-rectal spaces) are very important and from the biomechanical point of view resemble bonds that are stuck together. In fact, their resistance has the effect of interlocking neighbouring surfaces, and so effects a better distribution of pressures that are exerted and of their absorption. The changes that take place at rest and at movement of the pelvic organs during the menopause and during pregnancy and the puerperium have been studied. The role of episiotomy in particular as a step towards preventing urinary incontinence is emphasized. In fact, it lessens the pull on the external fibres of the sphincter muscle of the urethra which are bound up with the tissues of the vaginal wall. We have found in 140 women who have been operated on for stress incontinence that 62% had a tear or an episiotomy that was carried out late and that was insufficiently large; 13.9% had a tear: and 11.4%, on the other hand, had an episiotomy without a tear. On the other hand, in another group of similar women over the age of 45 who had had an episiotomy, 16.17% had stress incontinence.

Episiotomy↗
PubMed1984

Hypothermia and electromagnetic rewarming in the rhesus monkey.

Five male rhesus monkeys (Macaca mulatta) were subjected, under ketamine anesthesia, to repeated hypothermia treatments that produced an average rectal temperature of 28.3 degrees C. Following hypothermia induction, the subjects were rewarmed using either a ventrally applied surgical heating pad supplied with 35 degrees C water or a radio-frequency (RF) induction coil operating at 13.56 MHz with an average specific absorption rate (SAR) calculated to be approximately 5.5 W X kg-1. A special temperature probe, nonperturbing to RF, was used in the RF rewarming experiments. Control experiments were also conducted in which only ketamine was administered over a 3-h period. RF rewarming to 35 degrees C typically required only 50 min; whereas, an average of 137 min was required for heating-pad rewarming. Analyses of blood serum collected during and up to 48 h after hypothermia treatments showed elevations at 24 h in creatine phosphokinase (CPK), lactic dehydrogenase (LDH), and glutamic oxaloacetic transaminase (GOT), and these elevations were highest for the ketamine controls and lowest for the RF rewarming experiments. The subjects have been periodically examined since these experiments, and all appear to be in good health. It is concluded that the careful application of RF energy to the central core of the body can successfully be used for rewarming purposes, is more effective than externally applied rewarming techniques, and is potentially useful in remote locations.

Animals↗
PubMed1984

Absorption of enprofylline from the gastrointestinal tract in healthy subjects.

Enprofylline, a new potent bronchodilator xanthine drug, was given orally as an aqueous solution to 6 healthy subjects in single doses of 2, 4 and 6 mg/kg. The two lower doses produced plasma concentrations in the range 1-4 mg/l, i.e. in the assumed "therapeutic interval" according to previous animal studies. A high 24 h urine recovery of unchanged drug, with mean values for the three dose levels ranging from 85 to 91% of the given dose, indicated good absorption and little metabolism. The dose-corrected area under the plasma concentration-time curve rose with dose as the latter was increased from 2 to 6 mg/kg. This indicates that the elimination of enprofylline is capacity-limited at high doses. Double peaks in the plasma concentration-time curves at the higher dose levels suggested intermittent and delayed gastric emptying as a possible explanation. This hypothesis was confirmed by studies in 6 other healthy subjects, who received the drug solution by three different routes; by mouth, via a catheter in the duodenum, and rectally via a catheter in the colon. The corresponding time to peak values (mean +/- SEM) were 32.5 +/- 8.7, 13.3 +/- 2.5, and 157 +/- 23 min.

Adult↗
PubMed1985

Antibodies to normal human colon membranes: preparation, characterization and tissue distribution.

Rabbit antisera were raised to a membrane fraction of normal human colonic epithelium. After absorption, two antisera appeared to show restricted epithelial specificity when tested on routine paraffin wax-embedded histological sections by the indirect immunoperoxidase technique. The reaction was intense on epithelial cells of large and small intestine, and positive on stomach and duodenum, bile ducts in liver, gall bladder, pancreas and salivary gland. A very weak reaction was also seen in the bronchus and lung. There was no reaction with stromal, vascular or muscle components. All other tissues tested were negative, including hepatocytes, ectodermally-derived glandular epithelia, urogenital tissues and lymphoid organs. The antigen was also detected in 21 primary and metastatic large bowel carcinomata. By immunofluorescence, the antisera reacted with the colon adenocarcinoma-derived HT29 cell line and with primary colon epithelium explant cultures, but not with cultured fibroblasts. By immunoblotting of HT29 whole cell lysates, a triplet of polypeptides of approximate molecular weight range 55 000 to 60 000 were detected. This specificity appeared to be unrelated to previously described normal or tumour-associated antigens by criteria of tissue distribution, immunolocalization, molecular weight, and either absorption or radiobinding assays, or both.

Antibodies↗
PubMed1982

Methimazole: an alternative route of administration.

Methimazole was administered orally and rectally in a single dose of 60 mg to six euthyroid volunteers (three females and three males). Blood levels of methimazole were the same whether administered by the oral or rectal route, with peak levels of 1184 +/- 118 and 1163 +/- 150 (+/-SEM) ng/ml respectively. This study provides evidence that the rectal administration of methimazole may be an alternative to treating hyperthyroid patients who are unable to take this drug by mouth.

Absorption↗
PubMed1993

Absolute bioavailability of an aqueous solution of 1-deamino-8-D-arginine vasopressin from different regions of the gastrointestinal tract in man.

The absolute bioavailability of an aqueous solution of 1-deamino-8-D-arginine vasopressin (dDAVP) from different regions of the gastrointestinal (GI) tract (stomach, duodenum, jejunum, ileum, colon, rectum) has been studied in 6 healthy, male volunteers aged 24 to 35 years, followed for 12 h after each drug administration. For i.v. administration the subjects received 4 micrograms dDAVP. For intestinal administration 400 micrograms dDAVP was directly applied to six distinct sites in the GI tract via two or four channel tubes with or without a distal occlusive balloon. Biological effects were assessed and plasma and urinary levels of dDAVP were measured using a specific, sensitive RIA. Urine osmolality remained elevated and diuresis decreased for 12 h following dDAVP administration irrespective of the site of application. After i.v. administration, the half-life of elimination of dDAVP was 60.0 min, plasma clearance 1.7 ml.min-1.kg-1, amount excreted in urine 2.0 micrograms and renal clearance was 0.8 ml.min-1.kg-1. The mean bioavailability (f) after gastric application was 0.19% (range 0.02-0.35%). f was 0.24% after duodenal application (range 0.04-0.62%), 0.19% after jejunal (range 0.01-0.41%), 0.03% after distal ileal (range 0.01-0.08%), 0.04% after proximal colonic (range 0.01-0.12%) and 0.04% after rectal (0.01-0.10%) application. The bioavailability was significantly higher in the three upper GI regions in comparison to the three lower regions. The bioavailability of dDAVP after gastric, duodenal and jejunal application was similar to that after swallowing a tablet in a previous study. Absorption from the ileum was lower than expected and no preferential site of absorption was found.

Adult↗
PubMed1996

Flux measurements across Caco-2 monolayers may predict transport in human large intestinal tissue.

Confluent monolayers of Caco-2 cells, a human colonic carcinoma cell line, have been used extensively to predict intestinal absorption. A direct comparison of uptake characteristics, however, between cell monolayers and human tissue is missing in the literature. We have determined the flux for a series of small organic molecules, peptide and protein therapeutics, across Caco-2 monolayers and normal human colonic and rectal tissue in vitro to assess whether or not a predictive correlation of transport exists. Caco-2 cells were grown to confluency of Snapwells, and human tissue was obtained from patients undergoing surgery for localized tumors. Mucosa-serosa fluxes were measured by HPLC for small molecules and peptides, and proteins were analyzed by ELISA or RIA. Permeability coefficients were calculated from flux data and compared with previously published coefficients where possible. The permeability coefficients for the examined molecules were of a similar magnitude across Caco-2 cell monolayers and human tissues, ranging from 10(-7) to 10(-5) cm/s. A best-fit analysis of a log-log plot of transport measurements obtained in these two systems gave a good correlation (R2 = 0.991). From this limited data set it appears that uptake characteristics for human colon and rectum are similar to those of Caco-2 cell monolayers. Thus, flux measurements across Caco-2 monolayers may be predictive for permeabilities of human colon and rectum for different classes of therapeutics.

Atenolol↗
PubMed2005

Response, thermal regulatory threshold and thermal breakdown threshold of restrained RF-exposed mice at 905 MHz.

The objective of this study was the determination of the thermal regulatory and the thermal breakdown thresholds for in-tube restrained B6C3F1 and NMRI mice exposed to radiofrequency electromagnetic fields at 905 MHz. Different levels of the whole-body averaged specific absorption rate (SAR = 0, 2, 5, 7.2, 10, 12.6 and 20 W kg(-1)) have been applied to the mice inside the 'Ferris Wheel' exposure setup at 22 +/- 2 degrees C and 30-70% humidity. The thermal responses were assessed by measurement of the rectal temperature prior, during and after the 2 h exposure session. For B6C3F1 mice, the thermal response was examined for three different weight groups (20 g, 24 g, 29 g), both genders and for pregnant mice. Additionally, NMRI mice with a weight of 36 g were investigated for an interstrain comparison. The thermal regulatory threshold of in-tube restrained mice was found at SAR levels between 2 W kg(-1) and 5 W kg(-1), whereas the breakdown of regulation was determined at 10.1 +/- 4.0 W kg(-1)(K = 2) for B6C3F1 mice and 7.7 +/- 1.6 W kg(-1)(K = 2) for NMRI mice. Based on a simplified power balance equation, the thresholds show a clear dependence upon the metabolic rate and weight. NMRI mice were more sensitive to thermal stress and respond at lower SAR values with regulation and breakdown. The presented data suggest that the thermal breakdown for in-tube restrained mice, whole-body exposed to radiofrequency fields, may occur at SAR levels of 6 W kg(-1)(K = 2) at laboratory conditions.

Animals↗
PubMed1976

Abnormalities of function and faecal water following the modified Soave operation for Hirschsprung's disease.

Fourteen out of 18 patients (78%) had abnormal function 32 months after the modified Soave pull-through procedure for Hirschsprung's disease. The abnormalities were loose stools [9], perianal excoriation [7], soiling [11] and rectal prolapse [7]. Excoriation was caused by stools containing an excess of water, particularly in the "extractable" phase, with raised Na+ and Cl- concentrations, osmolality and hydrogen ion (pH) but normal concentration of K+. A deficiency of dry stool solid was also demonstrated. Abnormalities were most marked in patients who had high inferior mesenteric artery ligation and residual proximal left colon. Faecal water abnormalities are due to failure of complete water and electrolyte re-absorption by the pulled-through bowel. Manometric studies indicate that post-Soave patients have a small, "spastic" rectum with poor reservoir capacity which leads to soiling. Perianal excoriation occurs when faecal composition is abnormal. Four patients were improved on small doses of oral Ispaghula husk fibre. Clinical improvements were associated with alterations in stool composition.

Anus Diseases↗
PubMed2001

A pharmacokinetic study of amoxycillin in febrile beagle dogs following repeated administrations of endotoxin.

The pharmacokinetics of amoxycillin was studied in nine male beagle dogs under healthy and febrile conditions. In Period 1, dogs received 20 mg/kg of an oral suspension of amoxycillin. Intravenous doses of saline, 2 and 20 microg/kg of endotoxin (LPS from Escherichia coli serotype) were administered to dogs (three per group) prior to administration of 20 mg/kg of amoxycillin in Period 2. Rectal temperature and behavioral changes were recorded and blood samples were collected over 12 h for pharmacokinetic analysis. Amoxycillin was assessed in plasma using liquid chromatography coupled with mass spectrometry. Plasma concentrations were analysed using a one-compartment model with lag-time for absorption using an iterative two-stage method. As compared with control groups, amoxycillin clearance decreased significantly with preliminary treatments of 2 microg/kg endotoxin (0.209 vs. 0.140 L/h kg, P < 0.05) and 20 microg/kg endotoxin (0.214 vs. 0.075 L/h kg, P < 0.05). As a result of this, the area under curve for the 2 and 20 microg/kg endotoxin groups increased significantly 100.4 vs. 149.4 microg h/mL (P < 0.05) and 99.2 vs. 277.7 microg h/mL (P < 0.05), respectively. Other drugs currently used for the treatment of fever and septic shock should be re-evaluated using a febrile animal model to avoid improper dose administration.

Administration, Oral↗
PubMed1989

Recent findings and future perspectives of digestive physiology in rabbits: a review.

The rabbit is one of the most common laboratory animals. Consequently, there is an enormous number of publications concerning its physiology. The present review is restricted to a special field and deals with the new findings of the rabbit's digestive physiology. For the sake of better intelligibility the most important antecedents are also given. First the particularities of feed intake regulation are demonstrated. The strong control mechanism can be disturbed by feed antinutritives, mycotoxins and high environmental temperature. Caecotrophy depends on three main factors: stimulation of rectal mechanoreceptors, perception of the specific odour of the soft faeces, and the inner motive determined by the blood level of metabolites and hormones. The species characteristics of proportions, pH conditions, microflora and -fauna of the rabbit's digestive tract are given. The digestion and absorption of dietary nutrients are discussed. Special sections deal with the sorption of electrolytes and VFAs in the gut, the caecal digestive process, the formation of hard and soft faeces and the role of the caecotrophy in stomachal carbohydrate degradation. A relatively new area, i.e. the development and maturation of the gastrointestinal tract, is also shown. The postnatal evolution of digestive enzyme activity is also summarized. The main endogenic factors (breed, sex, age, stress, caecotrophy, presence of hairball in the stomach) influencing the digestion of dietary nutrients are also described. The probable future trends are given, too.

Animals↗
PubMed1984

Rectal or axillary temperature measurement: effect on plasma bilirubin and intestinal transit of meconium.

Physiologic jaundice (5-6 mg/100 ml plasma bilirubin) is common and considered normal in newborn infants during the first week postbirth, but is considered abnormal in older infants. Early meconium passage correlates with lower plasma bilirubin concentrations. Rectal stimulation during rectal temperature measurement may aid passage of meconium containing potentially toxic, absorbable bilirubin. In this study, 100 clinically normal infants were assigned randomly to groups for rectal or axillary temperature measurement. The time of first meconium passage, time of first all-yellow stool, and total plasma bilirubin were compared between groups. Bilirubin was measured during metabolic screening at 48-80 h postbirth (mean 69 h in both groups). By this time 30 infants in the rectal group, but only 17 in the axillary group, had passed yellow stools (p = 0.011). The rectal group had lower mean (+/- 1 SD) bilirubin (5.5 mg/100 ml +/- 2.7 vs. 6.5 +/- 3.0, p = 0.042), and a trend toward earlier first meconium (5.9 h +/- 5.0 vs. 7.3 +/- 5.9, p = 0.096). For clinically normal infants in the first 48-80 h postbirth, these data suggest that rectal stimulation accompanying rectal temperature measurement enhances intestinal bilirubin excretion because of more rapid meconium passage.

Axilla↗
PubMed1989

Pharmacokinetics of rectal ketamine in children.

We have studied the pharmacokinetics of ketamine administered rectally in a dose of 10 mg kg-1 to five children aged 6-9 yr and mean weight 28.80 (SD 6.55) kg. An acceptable level of anaesthesia was not obtained in any patient. Despite this, the degree of analgesia obtained was good and no child required further administration of analgesics during the postoperative period. Tolerance to the suppositories was excellent. The absorption of ketamine was found to be relatively fast, with a median peak concentration of 160 ng ml-1 (range 96-250 ng ml-1) at 0.75 h (range 0.50-1.00 h) after administration. The plasma concentrations of norketamine were greater than those of the parent drug, with a maximum of 510 ng ml-1 (range 450-810 ng ml-1) at 0.81 h (range 0.50-1.00 h) after administration. The medians of the half-lives of ketamine and norketamine were 3.15 h and 2.56 h, respectively (range 1.57-4.95 h and 1.47-5.30 h, respectively).

Administration, Rectal↗
PubMed1985

Effects of intrauterine infusion of Escherichia coli endotoxin in anestrous and steroid treated pony mares.

This study was conducted to determine if Escherichia coli endotoxin was absorbed from the equine uterus and if exogenous progesterone and estrogen affected the absorption of intrauterine endotoxin. Six mature anestrous pony mares were used in three consecutive crossover experiments (Periods) with a 14 day recovery between each period. Mares were randomly assigned to one of two treatment groups (three mares per group) and received an intrauterine infusion of either saline or endotoxin. Treatment groups were reversed and readministered after 14 days completing a crossover design (Period 1). During Periods 2 and 3 the mares were treated with estradiol-17beta (4.0 mg/day) or progesterone (400 mg/day), respectively, for 5 days prior to receiving intrauterine infusions. On the day of intrauterine infusions rectal temperatures and jugular blood samples were obtained at 30 to 60 minute intervals. Blood samples were analyzed for total white blood cell counts and by Limulus Amebocyte Lysate Assays. There were no significant alterations in the observed parameters among the various treatment groups. These results indicated that intrauterine E. coli endotoxin was not absorbed from the uterus of anestrous pony mares in large enough amounts to produce a morbid condition and that prior exposure to exogenous progesterone or estradiol-17beta did not affect the absorption of endotoxin from the equine uterus.

Journal Article↗