Evaluation of Duogastrome (carbenoxolone sodium) for the treatment of duodenal ulcer: a multicentre study.

A double-blind study was carried out in 152 Canadian patients, 76 given Duogastrone (carbenoxolone sodium) capsules, 50 mg qid, and 76 given placebo capsules qid for 6 weeks. All patients had a duodenal ulcer diagnosed by roentgenography or endoscopy, or both. Evaluation of the efficacy of Duogastrone therapy was based on data from the 119 patients (59 treated with Duogastrone and 60 with placebo) who met all the strict requirements of the protocol. The ulcers healed completely in 75% (44/59) of the patients treated with Duogastrone and in 48% (29/60) of those treated with placebo; this difference is significant (P less than 0.01). The proportions were similar in the patients assessed only endoscopically: 76% (32/42) and 55% (26/47), respectively. In the group treated with Duogastrone the following side effects were noted: weight gain, edema, mild hypokalemia, increase in blood pressure and slight increases in serum concentrations of lactic dehydrogenase and alkaline phosphatase. None was serious. However, close clinical monitoring by weekly visits to their physician is recommended for every patient undergoing Duogastrone therapy, at least during the 1st month.     

Alterations of ultrastructure and physiology of chemoreceptor dendrites in blowfly taste hairs treated with vinblastine and colchicine

Vinblastine (10^?3 M) and colchicine (10^?2 M) dissolved in fly Ringer solution were applied to chemoreceptor dendrites in individual tarsal taste hairs of blowflies (Phaenicia serricata Meigen), and the resultant changes in the morphology and physiological responsiveness of the receptors were examined. While Ringer solution alone did not have any morphological or physiological effects, treatment with drugs dissolved in Ringer solution increased the latency of responses to sucrose and NaCl and decreased spike amplitude and frequency. The drugs also disrupted microtubules and caused the destruction of the distal end of the dendrites. The observations provide evidence that the microtubules have a role in maintaining the structural integrity of the dendrites. Anodal current applied along with a chemical stimulus (NaCl or sucrose) increased the action potential frequency of treated and untreated receptors, and the electrical current elicited spikes only from those receptors which were activated by the chemical stimulus alone. When drug treatment resulted in a complete cessation of response to chemical stimuli, the receptors were also unresponsive to electrical stimulation. The results of this study are discussed in relation to hypotheses of transduction in chemoreception.     

Sodium–Sulfur Flow Battery for Low‐Cost Electrical Storage

A new sodium–sulfur (Na–S) flow battery utilizing molten sodium metal and flowable sulfur‐based suspension as electrodes is demonstrated and analyzed for the first time. Unlike the conventional flow battery and the high‐temperature Na–S battery, the proposed flow battery system decouples the energy and power thermal management by operating at different temperatures for the storage tank (near room temperature) and the power stack (100–150 °C). The new Na–S flow battery offers several advantages such as easy preparation and integration of the electrode, low energy efficiency loss due to temperature maintenance, great tolerance of the volume change of the metal anode, and efficient utilization of sulfur. The Na–S flow battery has an estimated system cost in the range of $50–100 kWh^?1 which is very competitive for grid‐scale energy storage applications.     

Snaps of a tiny amphipod push the boundary of ultrafast,repeatable movement

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Evolution of antibiotic resistance genes: the DNA sequence of a kanamycin resistance gene from Staphylococcus aureus

The kanamycin resistance gene from Staphylococcus aureus has been sequenced and its structure compared with similar genes isolated from Streptomyces fradiae and from two transposons, Tn5 and Tn903, originally isolated from Klebsiella pneumoniae and Salmonella typhimurium, respectively. The genes are all homologous but, since their common ancestor, have undergone extensive divergence, with more than 43% divergence between the closest pair. The phylogeny of the genes cannot be made congruent to the phylogeny of the taxa from which they were isolated without requiring rather improbable differences in rates. One is therefore led to conclude that there have been multiple occurrences of gene transfer between these species. Thus, although they are homologous, they are neither orthologous nor paralogous. It is suggested that homologous genes of this type be called xenologous.