Lactulose or paromomycin do not affect ammonia generation in the isolated perfused rat small intestine.

It has been hypothesized that the beneficial effect on hepatic encephalopathy of lactulose or neomycin might be exerted by their effect on intermediary glutamine metabolism and ammonia generation within enterocytes. We examined glutamine consumption and the production of alanine and ammonia (net substrate exchange in nmol min-1 g-1) in isolated vascularly and luminally perfused small intestine from rats with and without pretreatment with lactulose (2.0 g/kg) or paromomycin (60 mg/kg). Without pretreatment, 50 mM lactulose or 1 mM paromomycin were equally ineffective to significantly reduce the consumption of arterial glutamine (-92 +/- 5 vs. -80 +/- 6 vs. -71 +/- 6 for controls, lactulose, or paromomycin; mean +/- SEM, n = 6 each, n.s. by analysis of variance), and the production of alanine (41 +/- 3 vs. 44 +/- 3 vs. 61 +/- 7, n.s.) or ammonia (42 +/- 6 vs. 42 +/- 6 vs. 38 +/- 6, n.s.). Similarly, glutamine utilisation, and the release of alanine and ammonia were not different after pretreatment for 10 days. Also, both agents did not reduce glutamine absorption from the lumen (-170 +/- 9 vs. -171 +/- 6 vs. -219 +/- 25, n = 5 each) or the concomitant vascular release of metabolic products alanine (92 +/- 7 vs. 78 +/- 10 vs. 77 +/- 10 vs. 77 +/- 7, n.s.) and ammonia (73 +/- 6 vs. 69 +/- 7 vs. 65 +/- 8, n.s.). Our results do not support the hypothesis, that lactulose or paromomycin reduce ammonia generation by small intestinal mucosa through a specific effect on intermediary glutamine metabolism.

Long-term treatment of latent portosystemic encephalopathy with branched-chain amino acids. A double-blind placebo-controlled crossover study.

This trial was undertaken to assess the safety and efficacy of long-term oral supplementation with branched-chain amino acids as an adjunct to conventional therapy in patients with stable cirrhosis and latent encephalopathy. Latent encephalopathy was diagnosed by psychometric testing, used to assess automobile driving capacity. Seventeen patients with impaired driving capacity received either branched-chain amino acids or placebo for 8 weeks before being crossed over to the other regimen for an equal period. Branched-chain amino acids but not placebo significantly improved psychomotor disturbances (p < 0.01) and driving capacity (p < 0.002). No adverse reactions were observed. We conclude that long-term branched-chain amino acid supplementation is well tolerated and effective in the treatment of impaired automobile driving capacity associated with latent portosystemic encephalopathy.

Impact of tropical conditions on thin layer chromatography in analytical toxicology: high temperatures and moderate humidities.

The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated.

[Internistic therapy of acute diverticulitis]. / Internistische Therapie der akuten Divertikulitis.

Diverticular disease of the large bowel is very common in Western societies. The clinical pattern reaches from uncomplicated diverticular disease to acute peridiverticulitis, that ultimately afflicts about one in four patients having colonic diverticulosis. The illness may be indolent or fulminant, depending on the degree of colonic spillage and its containment. Therapy is usually medical and consists of "resting" the bowel, administering antibiotics and analgetics. Surgery is reserved for recurrent acute attacks, diffuse peritonitis, abscesses, fistulas, severe diverticular hemorrhage or obstruction. A diet rich in fibers reduces infectious complications.

[Pathogenesis and clinical aspects of primary liver cell carcinomas]. / Pathogenese und Klinik der primären Leberzellkarzinome.

The hepatocellular carcinoma is the most frequent primary liver cell carcinoma. On account of its geographical distribution with preferential occurrence in China, SE Asia and South Africa, exogenic causes are thought to be mainly responsible for its aetiopathogenesis. Besides mycotoxins, the hepatitis B virus infection (HBV) is particularly important. Integration of HBV-DNS into the hepatic cell DNS is considered to be an initiatory step in hepatocarcinogenesis. Clinically the tumour usually becomes manifest by upper abdominal complaints. Curative treatment can be promising only with very small tumours which can be detected most safely via ultrasound examination and alpha-1-fetoprotein determination.

[Laser sclerostomy: an alternative to current surgical filtering procedures. Experimental studies]. / Laser-Sklerostomie: Alternative zu bekannten operativen fistulierenden Verfahren. Experimentelle Untersuchungen.

A new filtering procedure, laser sclerostomy, was performed in 12 rabbit eyes by combined application of an argon and a YAG laser. In 10 cases an open fistula connecting the anterior chamber and the subconjunctival space could be demonstrated histologically. As neither the conjunctiva nor the globe are incised "ab externo," the possibility of an intraoperative infection is excluded and the risk of postoperative scar formation is minimized. Consequently, laser sclerostomy promises a new approach to glaucoma control in human eyes, too.

[Ocular outflow resistance and rate of secretion of aqueous humor following iridotomy and posterior capsulotomy with the Nd:YAG laser]. / Untersuchung des okulären Abflusswiderstandes und der Kammerwassersekretionsrate nach Iridotomie und hinterer Kapsulotomie mit dem Nd:YAG-Laser.

When the Nd:YAG laser is used for iridotomy and posterior capsulotomy an elevation in the intraocular pressure (IOP) is often found within the first few postoperative hours and in some cases for even 1-3 days. In 39 eyes the changes in postoperative intraocular pressure were noted and the preoperative as well as the postoperative outflow facility and aqueous secretion flow measured by oculopressiontonometry. The results demonstrated that in both iridotomy and posterior capsulotomy a reduction in the outflow facility caused the postoperative rise in IOP. Aqueous secretion flow did not increase. Most iridotomy patients had glaucoma and consequently reduced preoperative outflow facility. This determined the postoperative IOP elevation. In capsulotomy patients, no such correlation was evident, but the role of the laser energy applied seems to be more important according to our results.