Stress Lowers Sperm Count By Overwhelming Cells That Make Testosterone
...ents, "I am ultimately interested inthe control of testosterone production. Anytime you look at the biosynthesis o... of 11ßHSD-1 toneutralize it, shortcircuiting testosterone production. Without testosterone,other sperm-making cells do not begin to manufacture sperm. Enzyme ...Research Finds Alligator Problems Also Evident In Less Polluted Lakes
...ny of the same problems it had seen before: lower testosterone levels and small penis size in male alligators. In...sociated with reproduction -- the steroid hormones testosterone and estradiol -- but now we have evidence of disruption in other endocrine-controlled systems," Cra...High Testosterone Level May Lead Male Junco To Stray From Mate
...copulate with neighboring females? High levels of testosterone may be part of the answer, according to anew study...nd that male dark-eyed juncos that were givenextra testosterone during the breeding season were more likely than normalmales to fertilize females other than their m...Penn Researchers Find Mutation In Prostate Cancer Gene
...3A4 gene because one of its functions isto process testosterone through the body and because there is a strong correlation between elevated testosterone levels and thedevelopment of prostate cancer. Rebbeck and his colleaguespredict that a mutation in...New Study Highlights Hazards On Hormone Disrupting Chemicals
...nt plantshave shownskewed sex ratios and decreased testosterone levels. Epidemiological studies ofSwedish fishermenshowed an increased low birth weight for infants among mothers with aconsumption of fatty fishfrom the Baltic Sea. "This is not a new problem. We know that hazardous substances are present in theenv...Cardinals Can Recognize Gender By Song, Columbia University Biologist Finds
...n a laboratory, and, as they developed, found that testosterone levels shot upin the males at about the time their songs became more stereotyped and lessnasal. Dr. Yamaguchi says that young cardinals have a babbling phase similar tothat in humans, that they then learn songs from older cardinals, and that in thej......k of prostate cancer byreducing the levels of both testosterone and certain enzymes that metabolizetestosterone in...tosterols, the typeof fat found in plants, reduced testosterone in the blood stream by 33 percent. A high level of testosterone has been implicated as a risk factor......erentiate in the female gonad. The male sexhormone testosterone leads to the maintenance of the male sex duct system in thefemale. Additionnally, the anlage of the female duct system, the Mlerian duct,is absent in either sex. The survival, axonal outgrowth and target innervation of sensory neurons dependson facto...Melatonin Shapes Brain Structure In Songbirds
...rs in the spring iswhat leads to a higher level of testosterone and prompts males to sing more toattract mates and...very fall. Scientists were able to link the risein testosterone to actual physical changes in the brain's HVC. But in recent years, Johns Hopkins scientists...... andsignaling the receptors to produce estrogen or testosterone via anothermechanism - perhaps the extracellular signal that culminates in phosphorylation. On another level, the findings regarding SF-1 may have led researchers to a newappreciation for the complexity of nuclear receptor action and how thesefunctio...Plant-Based Fat Inhibits Growth Of Breast-Cancer Cell Line, UB Researchers Show
...e risk of prostate cancerby reducing the levels of testosterone and certain enzymes that metabolizetestosterone into more active forms. "If we know how phytosterols work, we can advise people how to modifytheir diets to reduce their risk of cancers, or we could eventually design drugsto target systems t...Antbird capable of increasing testosterone level when threatened
...ted antbirds (Hylophylax n.naevioides) raise their testosterone levels when necessary in the "off-season"to boost ...linois,studied the neotropical antbirds, measuring testosterone levels by blood teststaken at different times over two years in the 10-acre natural habitat of a bir......, as concentrations of DDEincrease, the ability of testosterone to properly bind and signal target cellsto initiate the functions that they are programmed to carry out decreases. Among the 30 percent of the study population for which DDE levels weremeasurable, concentrations ranged from 0.1 to 0.63 nanograms per ...Cedars-Sinai medical tip sheet (b)
Experimental testosterone patch shows promise for treating diminished sexual...omen According to a recent study, an experimental testosterone patch offers new hopefor women who suffer from diminished sexual function as a result of surgicalmen...Study finds prenatal exposure to testosterone boosts smoking
...ead, the two have discovered that higher levels of testosterone --the so-called "male" hormone -- in pregnant smok...portantfinding because it wasn't known before that testosterone had this effect," Udrysaid. "From a practical point of view, it may be less important because there'...Genetic mutation tied to increased prostate cancer risk in African-American and Latino men
... words, that it can feed off of male hormones like testosterone in much thesame way that some breast cancers rely ...id5a-reductase, which controls the "activation" of testosterone -- i.e., itsmetabolism into dihydrotestosterone (DHT). DHT is an androgen that is some 10to 50 time...Testosterone, stress may not suppress immune system after all
... long hasmaintained a correlation between elevated testosterone levels and a suppressedimmune system. After all, ...ssive play such a vital role? "The whole idea that testosterone and stress suppress the immune system makesabsolutely no sense evolutionarily," says Braude. "Why w...CYP17 gene proves important in determining bone growth, find University of Pittsburgh investigators
... a minor gene mutation produce more of the hormone testosterone and mayhave stronger, larger bones, according to J...in thecytochrome P450c17 (CYP17) gene produce more testosterone and havelarger, stronger bones. CYP17 is responsible for making testosterone, a hormonethat is impo......alled the medial preoptic nucleus(MPN). There, the testosterone is converted to another hormone, estradiol.Estradi...n a certain gene. Becausefemales produce levels of testosterone that are insignificant, their brainsproduce far fewer progesterone receptors....