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Previous evidence suggests that substance P (SP) activates subpopulations of neurons within the dorsal motor nucleus of the vagus (DMV). In this study we aimed at identifying these subpopulations in relation to their gastrointestinal projection organs or vagal branches and characterizing pharmacologically the SP response. Using whole cell patch-clamp recordings from identified gastrointestinal-projecting vagal motoneurons, we found that SP induced an inward current in all neuronal groups except for cecum-projecting cells. The lowest percentage of SP-responding neurons was found in fundus-projecting cells, where SP also had a concentration-response curve that was shifted to the left (P < 0.05). Independently from the projections, the SP response was reduced by sendide and MEN 10,376 and mimicked by a combination of [Sar(9)-Met(O(2))(11)]SP and alpha-neurokinin. SP and alpha-neurokinin also increased the frequency, but not the amplitude, of postsynaptic currents. In conclusion, we demonstrated that SP induces both pre- and postsynaptic effects on DMV neurons via activation of neurokinin NK(1) and NK(2) receptors. The magnitude of the SP response was correlated to the peripheral target organ.

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The authors present a case report on body piercing involving oral sites. Common locations and types of oral jewelry and piercing techniques are discussed. Oral considerations of intraoral piercing are emphasized.

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The influence of response options for and location of frequency of alcohol use items in a self-administered microcomputer interview were evaluated in a randomized, experimental study of 296 clients at a west coast treatment site for drinking drivers. Respondents were asked about their frequency of alcohol use in the last 7 days, 30 days, 90 days, and 180 days with three methodological factors randomized: (1) how quantitative the response options were; (2) order of presentation of close-ended response options; and (3) relative placement of alcohol use items in the questionnaire. Results indicate that these methodological factors had minimal influence on self-reports of the frequency of alcohol use. Only two statistically significant effects out of 44 possible were observed. The findings of this study suggest that frequency of alcohol use reports by drinking drivers yield similar information for a range of different response formats and location of the items in a microcomputer interview.

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Growth of Escherichia coli was faster in liquid cultures than on the same medium solidified with agar. Colony profiles indicated a common basic structure with a size variation due to nutritional conditions. Radial growth rates were linear and height also increased approximately linearly, especially in the early part of the growth period. The ratio of rate of height increase to diameter increase depended on nutrition. Conditions favouring rapid growth led to faster radical growth relative to height increase. A rise in incubation temperature led to increases in height and in diameter: however, diameter increased relatively more than height. These results are discussed in terms of the structure of the colony.

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Young colonies of two swarming organisms, Bacillus subtilis and Proteus vulgaris, grew about as quickly on solid media as in liquid culture whilst four non-swarming organisms, Bacillus cereus, Enterobacter cloacae, Escherichia coli and Staphylococcus albus, all grew slower on solid than in liquid media. Oxygen uptake by young colonies of B. subtilis, followed manometrically, increased exponentially at about the same rate as unrestricted aerobic growth. All other colonies demonstrated accelerating respiration which was either not strictly exponential or, in the case of S. albus, definitely biphasic, with a fast then a slow exponential rate of increase. Actual and potential respiration was determined for each species by measuring oxygen uptake before and after resuspending the colony in liquid medium. The ratio of actual to potential respiration was largest in the flat, spreading B. subtilis and smallest in the small, hemispherical S. albus. Calculations suggest that oxygen penetrates between 31 and 41 micron into colonies of B. cereus, Ent. cloacae and E. coli and only 9 micron into colonies of S. albus.

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Growth yields, enzyme activities, cytochrome concentrations and the rates of product formation were determined in Propionibacterium shermanii cultures grown in a chemostat with lactate as the energy source at various concentrations of oxygen. Oxygen was toxic when its partial pressure in the inflowing gas was just sufficient to give measurable dissolved oxygen concentration in the culture, when it inhibited lactate oxidation and NADH oxidase activity. Below this oxygen concentration, P. shermanii behaved as a facultative anaerobe. The adaptation from anaerobic metabolism to aerobic metabolism, however, was complex. Low partial pressures of oxygen led to decreased cytochrome and membrane-bound dehydrogenase activities and molar growth yield. Above an oxygen partial pressure of 42 mmHg in the inflowing gas stream, these changes were reversed, leading to an aerobic type of metabolism. At the highest subtoxic concentration of oxygen used (330 mmHg in the input gas), lactate was oxidized mainly to acetate and carbon dioxide and the rate of propionate formation was very low. The high molar growth yield obtained under these conditions suggested that lactate and NADH oxidation via the cytochrome electron transport system was coupled to ATP synthesis.

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