495 research outputs found

    Effects of transcendental medication on blood pressure

    Get PDF
    Many prevention and treatments methods exist for hypertension, but not all are effective or easy to incorporate into one\u27s life. Stress-reduction methods, including Transcendental Meditation (TM), has been suggested as such a method, but have received inconsistent reviews about its effect on blood pressure. This literature review of twelve clinical studies concludes patients who practice TM can significantly reduce blood pressure. The technique was found to be effective for groups at high risk for hypertension, such as African-Americans, as well as low-risk groups. TM also appears to be more effective than progressive muscle relaxation, another popular stress-management technique. TM should be incorporated into plans for treatment of hypertension

    In Memoriam: Theodore Louis Jahn

    Get PDF
    Dr. Theodore Louis (Ted) Jahn, Professor-Emeritus of Biology at the University of California at Los Angeles, died 1 May, 1979 following a cerebral hemorrhage. A longtime member of the Iowa Academy of Science, he was among the first to receive its Award of Merit

    Investigation of urinary steroid metabolites in calf urine after oral and intramuscular administration of DHEA

    Get PDF
    DHEA (3ß-hydroxy-androst-5-en-17-one) is a natural steroid prohormone. Despite a lack of information on the effect, DHEA and other prohormones are frequently used as a food supplement by body-builders. DHEA is suspected for growth promoting abuse in cattle as well. Considering the latter, urine samples from a previous exposure study in which calves were exposed to 1 g DHEA per day for 7 days, were used. The calves were divided in three groups: one orally treated, one intramuscularly injected, and a control group. The effect of this treatment on the urinary profile of several precursors and metabolites of DHEA was investigated. Urine samples were collected several days before and during the 7 days of administration and were submitted to a clean-up procedure consisting of a separation of the different conjugates (free, glucuronidated, and sulfated forms) of each compound on a SAX column (Varian). An LC-MS/MS method was developed for the detection and quantification of several metabolites of the pathway of DHEA including 17a- and 17ß-testosterone, 4-androstenedione, 5-androstenediol, pregnenolone, and hydroxypregnenolone. Elevated levels of DHEA, 5-androstenediol, and 17a-testosterone were observed in the free and sulfated fraction of the urine of the treated calves, thus indicating that the administered DHEA is metabolized mainly by the ¿5-pathway with 5-androstenediol as the intermediate. Sulfoconjugates of DHEA and its metabolites were found to constitute the largest proportion of the urinary metabolites. The free form was also present, but in a lesser extent than the sulfated form, while glucuronides were negligible

    Two New Amoebae, Striamoeba sparolata n. sp. and Flamella tiara n. sp., from Fresh Water

    Get PDF
    Author Institution: Department of Biological Sciences, Youngstown State University and Department of Physiology and Cell Biology, University of KansasTwp new amoebae are described from phase contrast observations made on specimens collected from Florida and Ohio, USA. Ohio specimens occurred among Aufwuchs on the midland painted turtle, Chrysemys picta marginata, and the common snapping turtle, Chelydra serpentina serpentina, while Florida specimens were found among the bottom detritus in muddy ponds. Striamoeba sparolata n. sp. (Thecamoebidae) is spearhead-shaped, 35-45 (xm by 12.5-22.5 |^m at the broadest point when in motion, with a clear bulbous anterior end and smooth uroid. There are usually two indistinct dorsal ridges, a spherical nucleus, 2-4 jam in diameter with a variable number of parietal nucleolar pieces and many endoplasmic lightrefractile granules. No pseudopods are formed during locomotion. Flamella tiara n. sp. (Flabellulidae) exhibits continuous changes in shape while in rapid motion but is more or less broadly arcate in steady slow progress. This amoeba is 30-40 |im wide, 12-25 |^m long, with many conical, papulate subpseudopodia extending from the body surface and leading edge. Adhesive, pseudo-uroidal filaments are trailed. An indistinct, spherical nucleus, about 3.5 (im, is present. The endoplasm is finely granular with no crystals. These two rarely encountered species occur as small populations and the present description will enable recognition by future researchers

    A Possible Explanation of the Gel-Sol Changes in Amoeboid Movement, Based on the Muscle Contraction Theories of Szent-Gyorgyi

    Get PDF
    The possibility that amoeboid movement and muscle contraction may be very similar and, perhaps, identical physico-chemical phenomena has occurred to numerous investigators during the past century. Ecker (1849) may have been the first to express this idea in the literature in terming muscle differentiated contractile substance and sarcode undifferentiated contractile substance. Only recently, however, has evidence accumulated from the fields of biochemistry and physiology which bids fair to establish the reality of that possibility

    In Defense of Ambiguity

    Get PDF
    If I recall correctly, one of the first adjectives I learned as a freshman in college was ambiguous. I do not remember looking it up in any dictionary when I learned it after the first mid-term tests. It was then enough for me to learn that if a professor\u27s test-questions were deemed ambiguous, I could excuse my failure to answer test-questions accurately and blame the professor for having hidden from me what I should have learned and understood. In my years since, as a professor, I find that the freshmen and upper classmen and even graduate students are still sophomoric in their use of this unacademic cop-out

    Dietary calcium decreases but short-chain fructo-oligosaccharides increase colonic permeability in rats

    Get PDF
    An increased intestinal permeability is associated with several diseases. Nutrition can influence gut permeability. Previously, we showed that dietary Ca decreases whereas dietary short-chain fructo-oligosaccharides (scFOS) increase intestinal permeability in rats. However, it is unknown how and where in the gastrointestinal tract Ca and scFOS exert their effects. Rats were fed a Western low-Ca control diet, or a similar diet supplemented with either Ca or scFOS. Lactulose plus mannitol and Cr-EDTA were added to the diets to quantify small and total gastrointestinal permeability, respectively. Additionally, colonic tissue was mounted in Ussing chambers and exposed to faecal water of these rats. Dietary Ca immediately decreased urinary Cr-EDTA excretion by 24 % in Ca-fed rats compared with control rats. Dietary scFOS increased total Cr-EDTA permeability gradually with time, likely reflecting relatively slow gut microbiota adaptations, which finally resulted in a 30 % increase. The lactulose: mannitol ratio was 15 % higher for Ca-fed rats and 16 % lower for scFOS-fed rats compared with control rats. However, no dietary effect was present on individual urinary lactulose and mannitol excretion. The faecal waters did not influence colonic permeability in Ussing chambers. In conclusion, despite effects on the lactulose: mannitol ratio, individual lactulose values did not alter, indicating that diet did not influence small-intestinal permeability. Therefore, both nutrients affect permeability only in the colon: Ca decreases, while scFOS increase colonic permeability. As faecal water did not influence permeability in Ussing chambers, probably modulation of mucins and/or microbiota is important for the in vivo effects of dietary Ca and scFOS

    Amoebas That Can Blow Your Mind

    Get PDF
    Until the mid-1950\u27s it was assumed by biologists and physicians that the only amoeba that endangered human comfort is the one that infects the digestive tract, causing amoebic dysentery in the susceptible and unwary tourist exposed to its more virulent varieties. Although that one, known to biologists as Entamoeba histolytica, sometimes escapes to the other parts of the body to cause sores and disturbances, it rarely causes death of its host, being a generally well-behaved parasite

    Tetrahymena: Cell for All Seasons

    Get PDF
    Certain protozoa have often been the cellular animals of choice for research and teaching in the past 100 years. In 1926, Asa Schaeffer (20) placed the amoeba at the pinnacle for animals that serve as primary research tools, along with the dog and the frog. Paramecium (one or more of its species) and Euglena (one or more of its species) are other protozoa (the latter, also an alga) well-known and oft-employed in both teaching and research. In the past 40 years, however, another protozoan has gained prominence in research, equalling - even superseding - the three mentioned above. Its generic name: Tetrahymena
    • …
    corecore