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Biomedical subjects

R L Mueller

Publications and source records attributed to R L Mueller.

At least 37 records · Page 2Linked to original sources
PubMed1986

[Campylobacter-like bacteria (C. pylori) in the healthy stomach?].

UNLABELLED: Some authors recently published reports on the findings of unidentified S-shaped spiral bacteria, so called "Campylobacter pylori", in the gastric epithelium and the significant connection between these strains and gastric diseases. 24 fasting gastric juice samples of young healthy volunteers were now analysed bacteriologically using the campylobacter isolation techniques. RESULTS: It was not possible to find the so called "C. pylori" in the healthy stomach.

Bacteriological Techniques↗
PubMed1986

Nitrate and nitrite in normal gastric juice. Precursors of the endogenous N-nitroso compound synthesis.

The nitrate and nitrite levels of 75 gastric juice samples from young and healthy fasting volunteers were examined. For both parameters a dependence on the specific pH value of the secretion was detected. The rise of the nitrite level from normal 0.1 ppm in the acid to 1.4 ppm in the neutral range can be explained by the activity of the bacterial flora even in the healthy stomach, which has already been demonstrated earlier. The hitherto existing theory that nitrate originates exclusively from the salivary glands, and if not reduced to nitrite by bacteria in the mouth cavity, is brought into the stomach via swallowed saliva only, does not explain the observation that there is a rise in nitrate concentration in neutral juice, too. Further investigations have to be made to see whether there are other endogenous sources of nitrate except the salivary glands in the gastrointestinal tract. The environmental pollutant nitrate must be paid more attention to in future.

Adult↗
PubMed1985

[Bacterial colonization of the stomach caused by acid neutralization and inhibition of stomach emptying].

Gastric bacterial overgrowth was studied in 8 healthy volunteers. Total bacterial counts, nitrate-reducing bacteria and nitrite concentration were determined in fasting gastric juice before and after 4 weeks of treatment with a strong or with a mild antacid drug, a placebo preparation and the spasmolytic agent papaverine which is known to inhibit gastric evacuation. Placebo therapy and the mild antacid did not change any of the above parameters studied. The strong antacid caused a significant increase in the pH of gastric contents which was accompanied by an enormous increase in total bacterial counts, nitrate-reducing bacteria and nitrite concentration. Papaverine which did not cause a significant elevation of pH also definitely increased bacterial counts and nitrite concentration of gastric juice. Four weeks following termination of each treatment procedure, however, all changes outlined above had returned to pretreatment values. These results indicate that reversible gastric bacterial overgrowth under therapeutical conditions may occur when acidity of the stomach is reduced or gastric evacuation is retarded.

Adult↗
PubMed1984

[Bathing caps and germ shedding of human scalp hair].

With three groups of 30 test subjects each, having short, medium-long and long hair, as well as with a model test using a woman's wig it was possible to show that by wearing bathing caps the transfer of germs from the scalp hairs to the swimming-pool water can be reduced considerably, either by the isolation of the hairs from water when snugly fitting water-tight bathing caps are used, or by a reduction of the germ-carrying hair surface rinsed by the water, which is always the case, even when using water-permeable caps. The effect is the greater, the larger the natural hair surface is. The rule that persons with long hair of either sex should wear bathing caps proves again justified although the prescriptive use of bathing caps by "the long-haired" earlier was based on other concepts. The population of germs settling on bathing caps does not in the least reach the germ counts discharged into the swimming-pool water when no headgear is used. Nevertheless, the issue of disposable bathing caps, which is occasionally practised, must be welcomed for reasons of hygiene. The use of bathing caps not only diminishes the discharge of colony forming units (CFU) but also prevents the indicators of pollution, pathological and occasionally pathological germs being washed into the water from the hair. Reference is also made to the possibility that a snugly fitting bathing cap protects the swimmer against the risk of contracting otitis.

Bacteria↗
PubMed1984

[Dynamics of endogenous bacterial nitrite formation in the stomach. 1. Follow-up studies in humans under natural conditions].

The fasting gastric secretion was analysed both bacteriologically and chemically in 15 young, voluntary test subjects with histories of a healthy stomach and physiological gastric secretion tests (Basal Acid Output, Peak Acid Output) made at regular intervals of two and 4 weeks over a period of three and six months. Two thirds of the persons studied showed during the entire period of examination the same pH values with tolerable variations and, as a result, the same order of magnitude for the total germ count, the colony count of the nitrite-forming bacteria and for the NO2- concentration. From this the conclusion can be drawn that, depending on the acidity of the individual stomach, there is an autonomous bacterial flora, which repeated examinations have shown to remain unaltered in quality and quantity. It was only in one third of the test persons that major variations of the pH values could be recorded occasionally. This, however, invariably led to corresponding changes in the bacteriological and chemical parameters. For requirements imposed by preventive medicine and hygiene, in future greater attention must be paid to the bacterial flora of the intact stomach, while making due allowance for the endogenous nitrite formation.

Adult↗
PubMed1983

Chromatographic and histochemical identification of dopamine within an identified neuron in the leech nervous system.

Each segmental ganglion of the leech nervous system has two pairs of lateral roots extending to the body wall and viscera. A cluster of about eight neuron cell bodies is located proximal to the first major branch of each anterior root and is termed the anterior root ganglion (ARG). Only one of these eight cells is vitally-stained by Neutral Red dye and fluoresces an intense blue-green following the glyoxylic acid histochemical condensation. The emission spectrum of this anterior root cell (AR) is stable under continuous UV illumination and is bimodal, with peaks at about 480 and 515 nm. This spectrum is indistinguishable from that of millimolar solutions of dopamine (DA) in gelatin droplets following glyoxylic acid histochemistry. We utilized high performance liquid chromatography and an amperometric detector to measure DA within the AR neurosomata at 1.01 pmol/cell. The AR cells in this study had an average diameter of 23 micron and therefore, the minimum intrasomatal concentration of DA is 160 mM, an unusually high level for any neurotransmitter. We measured DA in anterior axons at 0.83 pmol, in segmental ganglia at 1.07 pmol, and in longitudinal connectives at 0.16 pmol. Control neurosomata (Retzius cells) and axonal tracts which lack blue-green fluorescence (posterior and distal anterior roots), had no detectable DA (less than 0.06 pmol/sample). These data establish that the catecholamine DA is responsible for the fluorescence of the AR cell.

Animals↗
PubMed1983

[Germ transfer into swimming pool water by head hair].

The transmission of germs from the hair of the head to the swimming pool water was examined. It was found that between 6 x 10(6) and 10 x 10(6) germs are transmitted, depending on hair length. A sex-specific difference has been proved to exist. The 1,500 investigations based on different methods have demonstrated that the proportion of Staph. aureus carriers in the hair of normal persons without hospital contact is only 10 per cent and thus much lower than reported in literature. Even indicators of faecal contamination and pollution (E. coli, coliform germs) were detected in the hair less frequently than is reported in literature. Surprisingly, no correlation was found to exist between the cleanliness of the hair (interval between the last shampooing and swimming) and the transfer of germs. Rinsing of the hair has been found to liberate considerable quantities of germs which otherwise are produced by sebaceous secretions. Thus, in 52 per cent of cases, after shampooing the germ counts were found to be the same as before shampooing or higher. As a result, shampooing appears to be an unsuitable measure of germ reduction and the only possibility of diminishing the germ load in swimming pools is to wear bathing caps. This problem will be investigated by us in greater detail.

Bacteria↗
PubMed1983

[Endogenous synthesis of carcinogenic N-nitroso compounds: bacterial flora and nitrite formation in the healthy human stomach].

The endogenous synthesis of cancerogenic N-nitroso compounds: Bacterial flora and nitrite formation in the human stomach. In the discussion of the endogenous nitrosamine synthesis, nitrites play a decisive role. Since in a healthy stomach the acidity important for the nitrosamine formation is present, but since this acid environment is hostile to the bacterial growth and thus counteracts bacterial endogenous nitrite formation, the oral cavity has so far been regarded as the main site of endogenous nitrite formation. An analysis of 130 gastric secretions taken from empty stomachs has demonstrated that also in a healthy stomach considerable germ counts may be obtained in part when acidity is lowered physiologically (e.g. at night). Nitrite concentrations, which are six times as high as the quantities supplied with the saliva at the same time, are also produced in the acid pH range from 4 to 6. Consequently, in a healthy stomach as well the quantity of nitrite available for an endogenous nitrosamine synthesis is by far higher than has been assumed previously. This physiological risk should be allowed for in evaluating the pathophysiological or therapeutic changes in the gastric environment.

Bacteria↗
PubMed1977

Performance of swine chilled during artificial rearing.

There were more deaths among neonatal swine artificially reared for 21 days in individual cages at 27.9 C than among pigs reared under similar conditions at thermoneutrality (34.6 C). Furthermore, these deaths occurred at a younger age in the chilled animals. Chilled swine gained less body weight than did warm pigs for the first 15 days of life, although the survivors of the 27.9 C environment weighed the same as warm survivors at 22 days of age. Plasma glucose, liver, and skeletal muscle glycogen concentrations were significantly lower in neonatal swine exposed to 27.9 C from 1 to 4 days of age. Plasma nonesterified fatty acids, glycerol, cholesterol, and triglyceride concentrations were not altered by chilling. However, these lipid variables were significantly higher in 4-day-old nursig pigs than in animals reared artificially for the same period on artificial food. Adrenal gland weights and adrenal medullary catecholamine-synthetic enzyme activities were not altered by exposure to 27.9 C in pigs 1 to 4 days of age.

Animals↗
PubMed1976

Puerperal laparoscopic sterilization.

Two hundred and ninety-seven consecutive puerperal laparoscopic sterilization cases during a five-year period are reviewed. There were six failures to complete the laparoscopic sterilization. A single case of anesthetic cardiac arrest constituted the only major complication. There has been no mortality. Two subsequent pregnancies occurred in this series, and their follow-up operative findings are reviewed.

Adolescent↗
PubMed1976

Sympathoadrenal Neurochemistry and early weaning of swine.

Three litters of pigs were weaned at 21 days of age, and 3 others were left with the sow. Pigs were killed at 21, 23, 28, or 39 days of age. Weaned pigs exhibited anxiety, gastrointestinal dysfunction, and decreased rate of body weight gain. Plasma glucose or liver glycogen concentrations were not decreased by weaning. Adrenal gland weights and tyrosine hydroxylase (EC 1.14.3a), dopamine beta-hydroxylase (EC 1.14.2.1), phenethanolamine-N-methyl transferase (EC 2.1.1), and monoamine oxidase (EC 1.4.3.4) activities were increased after weaning. Adrenal catecholamine and cortisol levels and dopa decarboxylase (EC 4.1.1.26) and catechol-o-methyl transferase (EC 2.1.1.6) activities were not significantly altered, although some increases were indicated. Cranial cervical ganglionic choline acetyltransferase (EC 2.3.1.6) and tyrosine hydroxylase activities were increased after weaning. Weaning of swine at 21 days of age is a stressful experience, and many effects persist for at least 18 days; however, growth was no longer impaired 18 days after weaning.

Adrenal Glands↗
PubMed1975

Ontogenesis of monoamine oxidase and catechol-O-methyl transferase in various tissues of domestic swine.

Activities of monoamine oxidase (MAO) and catechol-o-methyl transferase (COMT) in liver, kidney, heart, spleen, hindbrain, and adrenal glands were compared in adult dogs, cats, guinea-pigs, rabbits, rats, sheep, and 150-day-old swine. Swine had the highest COMT activity and dogs or cats, the lowest in most tissues. MAO was more tissue and species variable. The ontogenesis of MAO or COMT was evaluated in the same six tissues of swine from 10 days before birth through 150 days of age. COMT and MAO generally increased in swine kidney and liver with age, but the developmental patterns were more variable in other tissues. COMT increased in heart, spleen, and adrenals through 14 days of age, decreased in spleen and adrenals to 150 days, but remained elevated in heart. Brain MAO activities were near or above 150-day-old levels at birth and changed little with age. Cardiac MAO fell from birth to 70 days of age, while splenic and adrenal activities increased with age. MAO substrate specificity to tyramine, benzylamine, and serotinin along with selective inhibition by harmine, pargyline, and clorgyline were used as indices of multiple enzymic forms. Type B MAO may dominate in all swine tussues except spleen, although the biochemical characteristics of this enzyme form do not seem to fit all of the patterns described for other species. Thermal stability of MAO in swine resembles that in the guinea-pig.

Age Factors↗