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At least 865 records · Page 48Linked to original sources
PubMed2001

Intra-operative and post-operative hypercapnia leading to delayed respiratory failure associated with transanal endoscopic microsurgery under general anaesthesia.

We present an unusual case of hypercapnia and surgical emphysema during transanal endoscopic microsurgery, which led to delayed post-operative ventilatory failure. The hypercapnia and surgical emphysema were secondary to rectal insufflation with carbon dioxide used to facilitate visualization and resection of a rectal tumour. Despite a return to wakefulness after surgery, the patient's level of consciousness deteriorated in the recovery area as a result of hypercapnia. The PaCO2 rose to 16.8 kPa because of absorption of carbon dioxide from the surgical emphysema. On close examination, surgical emphysema was identified in unusual areas, including the anterior abdominal wall, both loins, both groins and the left thigh. Reventilation was required until these unusual carbon dioxide stores had dissipated. We discuss the need for prolonged post-operative vigilance in patients with surgical emphysema secondary to carbon dioxide insufflation, and the risk of delayed ventilatory failure.

Aged↗
PubMed1987

Laboratory evaluation of malassimilation in horses.

Malassimilation should be suspected in horses with weight loss in spite of a good appetite. Malassimilation is usually confirmed with oral glucose or D-xylose absorption tests, whereas the oral lactose tolerance test can be used to evaluate lactase deficiency in foals. Once malassimilation is confirmed, other diagnostic tests such as abdominocentesis, rectal mucosal biopsy, or exploratory laparotomy with intestinal biopsies may determine the etiology of malassimilation.

Animals↗
PubMed1986

Effect of concanavalin A on the aspirin concentration and distribution in the brain and plasma of rats.

The effects of concanavalin A (Con A) on plasma and brain concentration of aspirin (Asp) were investigated in rats. When Asp was administered in rats treated with Con A, the plasma and brain concentration of Asp and its metabolites (salicylic acid (SA), salicyluric acid (SU) and gentisic acid (GA)) were increased. Distribution of Asp and its metabolites into the hippocampus, striatum and hypothalamus were increased by treatment with Con A. Asp esterase activities in the small intestinal mucosa, liver and brain were increased by pretreatment with Con A, but these enzyme activities were decreased by a high dose of Con A. The inhibitory effect of Asp, SA, SU and GA on the writhing induced by acetic acid in Con A-pretreated mice was stronger than that in the control. A lowering of rectal temperature, after the administration of Asp, was stronger in Con A-treated rats than in control rats. These results suggested that Con A facilitated the absorption of Asp and enhanced the transfer of SA into the brain, and increased Asp esterase activities in various tissues.

Analgesics↗
PubMed2003

Absorption of L-lysine diatrizoate from the gastrointestinal tract: the effect of surgery, inflammation, and neoplasia.

BACKGROUND AND AIMS: To ascertain whether the absorption of L-lysine diatrizoate, a sodium-free salt of the contrast-giving diatrizoic acid from the gastrointestinal tract is increased by surgery, inflammation, and neoplasia. PATIENTS AND METHODS: The prospective study comprised 32 patients who were undergoing radiological examination of the upper gastrointestinal tract with a contrast medium containing L-lysine diatrizoate and 52 further patients who were undergoing examination of the lower gastrointestinal tract in the same way. The concentration of diatrizoic acid was determined by high-pressure liquid chromatography in blood samples taken before and immediately after the radiological examinations. The results were examined in terms of sex, age, surgical history, and any evidence of inflammatory or neoplastic diseases. RESULTS: The serum diatrizoic acid concentration in patients tested after oral administration was 3.62 microg/ml. In patients who had undergone operation the titer was lower than in those who had not been operated on. Serum diatrizoic acid concentration in patients tested after rectal administration was 0.30 microg/ml. In patients suffering from inflammatory conditions or neoplasms the titer was significantly higher than in the other patients. CONCLUSION: The L-lysine salt of diatrizoic acid is absorbed in larger amounts from the upper gastrointestinal tract than from the lower. Absorption is not increased after surgical operations on the viscera. However, inflammatory conditions and neoplasms involving the large bowel increase the uptake of the contrast medium from the intestine.

Abdomen↗
PubMed2006

Development and validation of a liquid chromatography method for the simultaneous determination of alpha-tocopherol, retinol and retinyl esters in human serum using a monolithic column for the monitoring of anticancer therapy side effects.

Among other side effects, administration of anticancer agents is accompanied by manifestations of gastrointestinal toxicity and disturbances of antioxidant balance. The monitoring of these toxic effects in clinical practice is impeded by a dearth of reliable laboratory methods. Therefore, a simple and rapid reversed-phase high-performance liquid chromatography procedure for selective and sensitive determination of retinol, a-tocopherol, and retinyl esters (retinyl-palmitate and retinyl-stearate) in blood serum has been developed and presented in this study. A Series 200 LC HPLC instrument from Perkin Elmer (Norwalk, USA) with diode-array detector (DAD) was used for the analysis. Separations of retinol, alpha-tocopherol, retinyl-palmitate, and retinyl-stearate were performed using a Chromolith Performance RP-18e, 100 x 4.6 mm monolithic column from Merck (Darmstadt, Germany). Gradient elution was used at a flow rate of 3 mL/min; the mobile phase was methanol-water (95:5, v/v) for 0-2.1 min and methanol-2-propanol (60:40, v/v) for 2.1-4.9 min. The total time of analysis was 6 min. The injection volume was 20 microL and the analysis was performed at ambient temperature. Detection of retinol, alpha-tocopherol, and retinyl esters was carried out at 325, 295, and 330 nm, respectively. For practical assessment of the method, the vitamin A absorption test was performed on seven healthy controls as well as on six patients with non-small cell lung carcinoma or head and neck carcinoma previously treated by chemotherapy and/or radiotherapy, six patients with rectal carcinoma before chemoradiotherapy, four patients with gastrointestinal stromal tumor (GIST) before treatment with imatinib, and a breast cancer patient with chemotherapy-induced diarrhea. Present data demonstrate the feasibility of large scale HPLC determination of vitamin E, vitamin A, and retinyl esters in human serum using a silica monolithic column, and this method may represent a valuable aid in the laboratory monitoring of the toxicity of anticancer therapy.

Absorption↗
PubMed1999

Evaluation of the functional significance of the colorectal valve used in rectal urinary diversion in children: a comparative study between cases with and without the valve.

OBJECTIVES: To study the long-term impact of functional isolation of rectal reservoirs on the blood chemistries and acid-base balance of children who underwent this type of urinary diversion. METHODS: A retrospective evaluation of 63 children with rectal reservoirs was performed. Of these, 40 had a colorectal valve and 23 had double-folded rectal reservoirs without a functional isolation valve. Evaluation included serum chemistry and arterial blood sample analysis to verify the impact of the created valve on homeostasis. RESULTS: There was a statistically significant difference between the two groups relative to the value of pH, P(CO2), bicarbonate, base excess, and chloride in favor of those having a colorectal valve. Reduction of the absorptive surface area of the colon is presumably the cause in view of the functional isolation created by the colorectal valve. CONCLUSIONS: In children, the long life expectancy and the benign condition for which they have diversion require the incorporation of the colorectal valve in any form of continent rectal diversion. Prophylactic alkalinization with strict follow-up is a must in those having no valve.

Acid-Base Equilibrium↗
PubMed1997

Clinical pharmacokinetics of meloxicam.

Meloxicam (CAS 71125-38-7, UH-AC 62 XX) is a new non-steroidal anti-inflammatory drug (NSAID) which was developed for the treatment of osteoarthritis and rheumatoid arthritis. The basic clinical pharmacokinetics of meloxicam (7.5-30 mg) have been investigated in 78 healthy male volunteers after single and multiple dosing via oral, intravenous and rectal routes. Plasma concentrations of meloxicam were determined by validated high performance liquid chromatography (HPLC) methods. The pharmaco-kinetic profile of meloxicam is characterized by almost complete absorption over a prolonged phase-avoiding high initial drug concentrations- and is bound to plasma proteins by more than 99.5%. Meloxicam is metabolized to four biologically inactive metabolites and excreted in urine and faeces with an elimination half-life (t1/2) of around 20 h. This is reflected in a total plasma clearance of 7 to 8 ml/min. Steady state is achieved within 3 to 5 days. In addition, the pharmacokinetic parameters are linear over the entire dose range, there are no changes with multiple dosing and bioequivalence was shown for a number of different formulations. The results indicate that meloxicam is suitable for once-daily administration and that a switch from one formulation to another is easily possible if necessary or convenient for the patient.

Adult↗
PubMed2003

[Absorption of L-lysine diatrizoate from the gastrointestinal tract: the influence of surgery, inflammation and neoplasia].

PURPOSE: To ascertain whether the absorption of L-lysine diatrizoate, a sodium-free salt of the contrast-giving diatrizoic acid, from the gastrointestinal tract is increased by surgery, inflammation or neoplasia. MATERIAL AND METHODS: Using contrast medium containing L-lysine diatrizoate for intestinal opacification, this prospective study compared 32 radiographic examinations of the upper gastrointestinal tract with 52 radiographic examination of the lower gastrointestinal tract. In blood samples taken from the patients immediately after the radiographic examinations, the concentration of diatrizoic acid was determined by high pressure liquid chromatography. The results were correlated with sex, age, surgical history and any evidence of inflammatory or neoplastic diseases. RESULTS: The serum diatrizoic acid concentration in patients after oral administration was 3.62 (95% CI, 2.86 - 10.17) microg/ml. The titer was lower in patients who had undergone abdominal surgery than in patients without surgery. Serum diatrizoic acid concentration in patients after rectal administration was 0.30 (95% CI, 0.13 - 0.60) microg/ml. The titer was significantly higher (p < 0.05) in patients suffering from inflammatory conditions or neoplasms than in the other patients. CONCLUSION: The L-lysine salt of diatrizoic acid is absorbed in larger amounts from the upper than from the lower gastrointestinal tract. Absorption is not increased after abdominal surgery. However, inflammatory conditions and neoplasms of the large bowel increase the uptake of contrast medium from the intestine.

Abdomen↗
PubMed2000

Liver and gut mucosa acetylation of mesalazine in healthy volunteers.

AIM: The aim of this investigation was to identify which part of a dose mesalazine is acetylated by enzymes in the gut wall during the absorption process, and which part by the liver enzymes after absorption. METHOD: This study was based on data from four bioequivalence studies of different formulations of tablets (gastro-resistant single dose 500 mg (n = 24) and prolonged-release tablets (single dose 1000 mg, n = 18; multiple dose 1000 mg t.i.d. six days n = 28), suppositories (single 500 mg dose, n = 24) and a study with two i.v. administrations of 100 and 250 mg mesalazine (n = 6). In total, 200 administrations were carried out and plasma concentration-time curves obtained and analyzed. There was a large variability in the absorption of mesalazine for all formulations. The plasma concentration-time curves of parent drug and metabolite acetylmesalazine run nearly parallel, independent of the formulation and the dose. Plasma and urine mesalazine and acetylmesalazine concentrations were determined according to validated methods using HPLC analysis with coulometric or mass-spectrometric detection. RESULTS: As a result of the large variations in release and absorption of mesalazine in the pharmaceutical formulations and administrations, it was possible to demonstrate that acetylation occurs in the gut wall and in the liver. By comparing oral and rectal data to intravenous data, it was possible to indicate where (and to what extent) acetylation occurs in the gut wall, in the liver, or both. Rectal administration of a mesalazine suppository and intravenous administration results in hepatic acetylation. Oral administrations of mesalazine results in both gut wall and hepatic acetylation. Acetylation by the gut wall amounts to 30% of the dose for gastroresistant tablets and to 40% of the dose for prolonged-release tablets.

Acetylation↗
PubMed1982

Cold exposure and absorption of colostral immunoglobulins by neonatal pigs.

To investigate the effect of cold exposure on absorption of colostral immunoglobulins, 56 piglets were weaned at birth and placed in either a thermoneutral (35 C) or cold (21 C) environmental chamber. Thermoneutral piglets had a survival rate of 62% at 48 h, but survival among cold-exposed piglets was only 36% (P less than .10). Cold aid reduced (P less than .01) rectal temperature by more than 6 C after 24 h of exposure. A constant amount of bovine colostrum was administered orally at 4 h after initiation of thermal treatments. Bovine immunoglobulin G1 (IgG1) was readily absorbed and reached a serum level of 17 mg/ml after 24 h. Bovine IgM also was absorbed and increased to approximately 2 mg/ml at 24 h. However, absorption of colostral IgG1 and IgM was not affected by cold exposure. Cold air increased (P less than .05) incidence of diarrhea by over five fold after 72 h, and severity of diarrhea was nearly doubled (P less than .01). Hematocrit was also higher (P less than .05) in cold-exposed piglets. These data demonstrate that a cold stressor sufficient to induce hypothermia does not impair absorption of colostral macromolecules in piglets. However, cold exposure was related to increase incidence and severity of diarrhea.

Animals↗
PubMed1993

Clinical and functional results of abdominal rectopexy with absorbable mesh-graft for treatment of complete rectal prolapse.

OBJECTIVE: To report the long term results of abdominal rectopexy in patients with complete rectal prolapse. DESIGN: Ongoing prospective randomised study. SETTING: Department of Surgery, Westfälische Wilhelms-University, Münster. SUBJECTS: 47 patients with complete rectal prolapse operated on between 1982 and 1989. INTERVENTIONS: Abdominal rectopexy with absorbable mesh made of either polyglycolic acid (n = 17) or polyglactine 910 (n = 30). MAIN OUTCOME MEASURES: Postoperative complications and late results at a mean of 50.5 (range 2-102) months after operation. RESULTS: Thirteen patients (28%) developed postoperative complications, most of them minor; there was one enterocutaneous fistula. Thirty five patients (74%) were available for late follow up. There were no case of recurrent prolapse and 5 (14%) had developed mucosal prolapse. Of the 22 patients who had been incontinent before operation, 8 had become totally continent and 6 partially continent Overall continence improved in 18 (51%) of the 35 patients. Three patients who were continent before operation had become incontinent. CONCLUSION: Absorbable mesh is a suitable material for abdominal rectopexy.

Absorption↗
PubMed1975

Electrical potential difference, sodium absorption and potassium secretion by the human rectum during carbenoxolone therapy.

The transmucosal electrical potential difference (pd) and the sodium and potassium net fluxes were measured in the rectum of subjects taking carbenoxolone. There was a rise in transmucosal pd persisting throughout treatment in all subjects which was accompanied by an increase in sodium absorption and potassium secretion. Comparison of the pd changes produced by carbenoxolone with those due to the mineralocorticoid 9-alpha-fluorocortisol showed that carbenoxolone had about 1/1000th the potency on a weight basis and the two drugs appeared to be additive in their effects. Topical instillation of carbenoxolone into the rectum produced an elevation of pd which persisted for three days. Amiloride and bendrofluazide did not interfere with these actions of carbenoxolone but spironolactone abolished them. One patient who developed fluid retention and hypokalaemia had a rectal pd similar to that of the other patients who had no side effects.

Adult↗
PubMed2002

A new method for characterizing the release of drugs from tablets in low liquid surroundings.

The purpose of this article is to introduce a method capable of determining early drug dissolution in small amounts of liquid. The method is based on the measurement of the alternating ionic current through a cell containing the dissolution medium and the substance to be dissolved. Both the initial and more prolonged absorption of liquid into tablets can also be determined by using the same technique. The method has been tested on two tablet formulations containing agglomerated micronized cellulose and NaCl as a model drug. Release of NaCl was delayed from both formulations; the extent of the delay was strongly formulation-dependent only when the surrounding liquid was in short supply. This finding shows that new drug dissolution phenomena may be encountered in small liquid volumes; these phenomena would not have been seen with the large volume methods normally used in in vitro dissolution tests. Hence, for formulations intended for sublingual, buccal, or rectal administration, i.e., in areas where liquid is scarce, in vitro dissolution tests should be performed in small volumes of dissolution medium.

Absorption↗
PubMed1979

Electron microscopic studies on transplantable mucus-secreting and tubular adenocarcinomas of colo-rectal origin in ACI/N rats.

Two transplantable, one mucus-producing (R-1) and the other tubular but less mucinous (R-2), adenocarcinomas were investigated electron microscopically. The R-1 tumor was composed of a large number of intermediate cells and mucus-producing cells, incompletely differentiated goblet-like cells and absorptive-like cells, and a small number of undifferentiated cells. The electron microscopic features of the mucus-producing cells exhibited distinctive features different from those of the epithelium of normal colon. They had highly electron-dense granules, expanded rER, well-developed mitochondria and Golgi apparatus. The R-1 tumor was found to be a well-differentiated adenocarcinoma in agreement with observations by light microscopy, while the R-2 tumor exhibited more malignant features than R-1.

Adenocarcinoma↗
PubMed1989

Characteristics of the gastrointestinal absorption of morphine in rats.

The absorption characteristics of morphine were investigated by using rat gastrointestine. Absorption and transport experiments were carried out by the in situ loop and the in vitro everted sac methods, respectively. Brush border membrane vesicles (BBMVs) were used for uptake experiments. Morphine and its metabolites, morphine-3-glucuronide (M-3-G), and morphine-6-glucuronide (M-6-G), in biological samples were simultaneously determined by high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection and electrochemical detection. In the in situ loop method, morphine was well absorbed in the order of jejunal site greater than duodenal site greater than ileal site greater than middle intestinal site greater than rectal site, but it was poorly absorbed from the stomach. In each of the everted duodenal and jejunal sacs, 2,4-dinitrophenol, a metabolic inhibitor, inhibited the transport of morphine from the mucosal side to the serosal side. Further, HgCl2 pretreatment reduced the absorption of morphine from the duodenal and the jejunal loops. The initial uptake of morphine by BBMVs was stimulated in the presence of an H+ gradient (inner pH 7.5 and outer pH 5.0) and an overshoot phenomenon was observed. The initial uptake showed concentration dependence, i.e., it was saturable. Results obtained in this study indicate that carrier-mediated transport stimulated by the H+ gradient is partly involved in the duodeno-jejunal absorption of morphine, although morphine is passively absorbed from other sites.

Animals↗