Aeromonas hydrophila toxins—intestinal fluid accumulation and mucosal injury in animal models

Strains of Aeromonas hydrophila were earlier shown to produce a heat-labile enterotoxin and two cytolytic toxins, alpha- and beta-haemolysin. These investigations have been extended. When separated from the cytolysins, the enterotoxin elicited fluid accumulation in rabbit intestinal loops. The electrolyte and albumin content of the fluid was similar to that of cholera toxin. The enterotoxin was non-injurious to the mucosa. Purified hemolysins did not give a positive loop test. They produced hemorrhagic enteritis with leakage of small amounts of hemorrhagic fluid. In electrolyte and albumin content this fluid differed from the fluid elicited by the enterotoxin. Prostaglandin inhibitors did not reduce the diarrheal response to Aeromonas enterotoxin. The cAMP inhibitor chlorpromazine reduced the fluid accumulation in rat and mice intestinal loops by 60%. Cholera toxin and Aeromonas enterotoxin may have a common pathway in the elicitation of intestinal fluid accumulation. By passage in intestinal loops, strains of A. hydrophila could regain lost enterotoxicity. Experimental diarrhea could not be induced in rabbits and rats with various enterotoxigenic strains of Aeromonas.     

Selective or routine intraoperative cholangiography: A cost-effectiveness analysis

In a retrospective analysis of 819 patients operated on for gallbladder disease, the costs and mortality rates were compared for 2 different strategies: (a) routine use of intraoperative cholangiography, or (b) selective use of intraoperative cholangiography on patients fulfilling at least 1 of 4 common clinical criteria. Selective use led to lower costs and lower mortality rates. The main reason for this outcome was that the benefits of detecting more stones in the bile duct by the routine use of cholangiography were counterbalanced by an increase in costs and risks because false-positive operative cholangiograms led to a greater number of unnecessary choledochotomies.     

Therapeutic efficacy by recombinant human granulocyte/monocyte-colony stimulating factor on mucositis occurring in patients with oral and oropharynx tumors treated with curative radiotherapy

BACKGROUND: Previous studies suggested granulocyte-macrophage-colony stimulating factor (GM-CSF) might be beneficial for radiotherapy-induced mucositis. This trial examined the efficacy of GM-CSF in reducing mucositis of the oral cavity and/or oropharynx compared with conventional treatment. METHODS: Mucositis, documented by a five-grade scale, was defined in patients with tumors of the head-neck. Centers were allowed to use their own preferred fractionation regimen. Randomization to treatment was decided before radiotherapy. Treatment with GM-CSF 4 microg/kg/d subcutaneous, started when patients displayed a mucositis score > or = 1.5. RESULTS: Ninety-two patients entered the study according to intention-to-treat principle. Twenty did not reach a mucositis index of 1.5. Sixty-one patients were included in the statistical analysis. Forty-five percent of the patients randomized to receive GM-CSF had a significant reduction of the mucositis more than one grade compared to 9% of the conventional treated. CONCLUSIONS: In severe mucositis, GM-CSF is more effective than conventional treatment.     

Einfluss der Blockade mit Lokalanästhetika auf die Stimulierbarkeit eines Nerven mit der peripheren Nervenstimulation

Zusammenfassung Es sollte untersucht werden, welchen Einfluss die Injektion einer geringen Menge Lokalanästhestikums an einen Nerven auf dessen Stimulierbarkeit mit der peripheren elektrischen Nervenstimulation hat. Bei 35 Patienten wurde randomisiert und verblindet an den N. ischiadicus entweder Kochsalzlösung oder Lokalanästhetikum injiziert; 30 s und 2 min nach der Injektion wurde die Stromstärke gemessen, die zu vergleichbaren Muskelreaktionen führte. Die Ergebnisse zeigen, dass nach 30 s bzw. 2 min bereits mit einem ausgeprägten Lokalanästhetikumeffekt gerechnet werden muss. Die Sicherheit, die die Nervenstimulation zur Vermeidung von Nervenschäden bietet, ist nicht mehr gegeben, wenn in dem Bereich, in den bereits Lokalanästhetikum injiziert wurde, erneut punktiert und nach weiteren Nerven gesucht wird. Es muss vor der Durchführung einer Regionalanästhesie in Multiinjektionstechnik bei enger anatomischer Beziehung der zu blockierenden Nerven gewarnt werden, da bereits anästhesierte Nerven bzw. Nervanteile eine schlechtere Stimulationsfähigkeit besitzen und somit evtl. bei der zweiten oder dritten Punktion geschädigt werden könnten.     

Do contraceptives influence the incidence of acute pelvic inflammatory disease in women with gonorrhoea?

The influence of different contraceptive techniques on the incidence of pelvic inflammatory disease (PID) in 672 patients with gonorrhoea have been studied. The lowest frequency of PID was found in patients using hormonal contraceptives (Group A), 8.8 per cent compared to 23.5 per cent in patients using intrauterine devices (Group B) and 15.1 per cent in patients using neither technique (Group C). In comparable control groups no significant differences in background factors, such as age, marital status and sexual activity were demonstrated. It is therefore concluded that the significantly lower incidence of PID in patients using hormonal contraceptives compared to the other groups and the high incidence of PID in patients using intrauterine devices is related to the contraceptive technique per se.     

Increased noradrenaline release in rat portal vein during sympathetic nerve stimulation due to activation of presynaptic beta-adrenoceptors by noradrenaline and adrenaline.

With the aim of investigating whether exogenous noradrenaline (NA) and adrenaline (A) can modulate transmitter release via the stimulation of presynaptic beta-adrenoceptors, 3H-release from isolated portal veins was studied after pretreatment with 3H-1-NA, phenoxybenzamine, desipramine and normetanephrine. NA (10 muM) and A (0.05 muM) increased the fractional 3H-release elicited by sympathetic nerve stimulation by 30%. This effect could be blocked by d, 1-propranolol which per se reduced the release by 10%. It is concluded that NA can facilitate its own release via a presynaptic beta-adrenoceptor-mediated positive feed-back mechanism and that adrenaline can stimulate this beta-adrenoceptor-mediated mechanism.     

Non-Animal Stabilized Hyaluronic Acid

Hyaluronic acid (HA) is a major component of human synovial fluid, providing the rheologic properties (elasticity and viscosity) that enable the synovial fluid to perform lubricating and shock-absorbing functions within the healthy joint. Over the last 2 decades, HA preparations have become established in intra-articular therapy of osteoarthritis (OA), particularly OA of the knee. Existing HA preparations, both cross-linked and non-cross-linked, are all administered by courses of multiple injections, and all have been associated with variable success rates. The clinical profile of an HA preparation is inextricably linked to the product's physicochemical properties. For example, the molecular structure of the HA affects the intra-articular residence time, which should in turn influence the duration of action post-injection. Non-animal stabilized hyaluronic acid (NASHA) is a new-generation HA preparation, produced wholly from non-animal sources. NASHA is stabilized using a carefully controlled cross-linking process, which increases the intra-articular residence time from hours to weeks. This facilitates single-injection treatment for OA without affecting the biocompatibility of HA. This review evaluates the properties of NASHA, including the available clinical data, in the context of previously developed HA preparations.     

Evaluation of Viability of Excised Rat Intestinal Segments in the Ussing Chamber: Investigation of Morphology,Electrical Parameters,and Permeability Characteristics

Purpose. To clarify relations between alterations in electrical and permeability data with time and to elaborate accompanying structural changes of intestinal segments in Ussing chamber experiments. Methods. Excised intestinal segments from the rat were studied in a modified Ussing chamber. Experiments were run up to 180 minutes during which the electrical parameters, PD, SCC, and R, were measured and the permeability coefficients (P_app) of mannitol and propranolol were determined. Each segment was observed under the light microscope for morphological evaluation. Results. PD and SCC values showed a decrease for most segments while the R values remained steady throughout the experiment. The P_app for propranolol increased aborally to the small intestine. For mannitol, the reversed was observed. In some cases, there was a time-dependent change in permeability for these marker molecules. The main morphological changes observed were a decreased nucleo-apical distance, decreased villi amplification factor, initial edema, cell sloughing, and epithelial restitution. Conclusions. The time-dependent changes in permeability coefficients of mannitol and propranolol are suggested to be related to changes in electrical parameters and morphological alterations. Presented data illustrates the importance of information regarding time-dependent structural changes for correct interpretation of permeability data.     

Immunofluorescence localization of proteins in semithin 0.2–1 μm frozen sections of the ear

Summary The present work describes a high resolution technique for locating proteins in frozen sections of the inner ear by immunofluorescence. Dissected organs are encapsulated in gelatin, and sections 0.1–1 m thick are cut at –100°C in a cryoultramicrotome. These are labelled with antibodies against two cytoskeletal proteins, actin and tubulin. Actin, which had previously only been described in the sensory cells, is found in the supporting cells as well. Tubulin is identified in the supporting cells and in outer spiral nerve fibres.Supported by grants from the Swedish Medical Research Council (no. 04x-02461), the Ragnar and Torsten Söderberg Foundation, and the Foundation Tysta Skolan