Male birth control pill moves a step closer 16th August 2012 Researchers have finally found a compound that may offer the first effective and hormone-free birth control pill for men. The study, published today in the journal Cell, describes how the small molecule makes male mice reversibly infertile, without putting a damper on their sex drive. When the animals stop taking this new form of birth control, their sperm rebound and they are able to produce perfectly healthy offspring once again. "This compound produces a rapid and reversible decrease in sperm count and motility with profound effects on fertility," said James Bradner of the Dana-Farber Cancer Institute and lead author of the study. A male birth control pill has been difficult to come by, in large part because of the challenge of getting any drug across the blood:testis barrier, where it can reach the sperm-generating cells. That lack of contraceptive alternatives for men is partially responsible for the high rate of unplanned pregnancies. Despite the unsatisfactory options for male contraception, nearly one-third of couples rely on male-directed birth control methods. Known as JQ1, the new compound developed in the Bradner lab works by targeting a testis-specific protein called BRDT that is essential for fertility. When mice are given the BRDT-inhibiting molecule, they begin producing fewer sperm and those sperm they do produce don't swim as well. "This is a good reason to get excited about low sperm counts," said Martin Matzuk of Baylor College of Medicine, another author of the report. Mating studies confirm that JQ1 indeed works as an effective contraception. Even better, those effects are completely reversible and without adverse consequences for the animals' testosterone levels or behavior. The small molecule also comes without any apparent side effects on the males' future offspring. "There has not been a new reversible contraceptive for men since the development of the condom, centuries ago," notes William Bremner from the University of Washington, Seattle. In an accompanying commentary, he refers to Matzuk and Bradner's contraceptive method as "a breakthrough new approach." "We envision that our discoveries can be completely translated to men, providing a novel and efficacious strategy for a male contraceptive," the researchers wrote, noting the high degree of conservation between human and mouse BRDT proteins.
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Late in the night Gholson came to the union captain's bedside for Miss Harper. Charlotte had sent him; the doctor had left word what to do if a certain patient's wound should re-open, and this had happened. The three had succeeded in stanching it, but Charlotte had prevailed upon Miss Harper to lie down, and the weary lady had, against all her intentions, fallen asleep. I was alone with the wounded captain. He did not really sleep, but under the weight of his narcotics drowsed, muttered, stirred, moaned, and now and then spoke out. "You're right, Sam," said George Bynes, who had hit up many a century for his town in bygone days, "tain't cricket. Else it's a[Pg 28] fluke; the man didn't ought to be allowed to hold bat in his hand. It's spoiling other folks' sport." But the Clockwork man made no reply. He stood in the middle of the stage and slowly[Pg 96] lifted a finger to his nose. The Curate's doubts returned. Something seemed to occur to him as he examined his companion more closely. "You haven't been taking anything, my good man, have you? Anything of an alcholic nature?" Walk equal courses in their yearly round, I. ¡°There was no need. She had taken only the imitations¡ªthe ones you found.¡± ¡°It¡¯s funny,¡± Jeff remarked. ¡°This-here psychology I¡¯ve read about ain¡¯t so far wrong when it says that folks who gets the wrong slant on a thing comes to believe it so strong that even the truth looks like a fib to them.¡± Then he began to come to himself and to listen to all that Felipa had to tell him of the many things she had not put in her short and labored letters. He saw[Pg 140] that she looked more beautiful and less well than when he had left her. There was a shadow of weariness on her face that gave it a soft wistfulness which was altogether becoming. He supposed it was because she had nursed him untiringly, as she had; but it did not occur to him to thank her, because she had done only what was a wife's duty, only what he would have done for her if the case had been reversed. Toward the end of the day he began to wonder that no one had been to see him, and he spoke of it. The storm passed, with all the suddenness it had come on, and Felipa rose, and dressing herself quickly went out upon the porch. Three drenched kittens were mewing there piteously. She gathered them up in her hands and warmed them against her breast as she stood watching the earth and sky sob themselves to rest. All the petunias in the bed by the steps were full of rain, the crowfoot and madeira vines of the porch were stirring with the dripping water. Many great trees had had their branches snapped off and tossed several[Pg 307] yards away, and part of the windmill had been blown to the top of the stable, some distance off. She wondered if Cairness had been able to get the cut alfalfa covered. Then she took the kittens with her to the house and went into the kitchen, where the Chinese cook already had a fire in the stove. She ordered coffee and toast to be made at once, and leaving the kittens in the woodbox near the fire, went back to the sitting room. She gave a dry little sob of unutterable glad relief and tried to raise her voice and call to him, the call they used for one another when they rode about the ranch. But the sound was only a weak, low wail. "Yes; you're in nice shape to send to the guardhouse. I'd sent you there quick enough if you were well, for telling me such a preposterous lie. You've usually paid more respect to my intelligence by telling me stories that I could believe if I wanted to, as I usually wanted do; but this is too much." "And then something happened," Dr. Haenlingen said tightly. "I know." It was quite dark when they reached Eggs Hole, and parted after kisses no longer as shy as they used to be. The year wore on. Kimberley and Ladysmith were relieved. Rye hung out its flags, and sang "Dolly Grey" louder than ever. Then Mafeking was saved, and a bonfire was lit up at Leasan House, in which a couple of barns and some stables were accidentally involved. Everyone wore penny medallion portraits of officers¡ªRoberts and Baden-Powell were the favourites at Odiam, which nearly came to blows with Burntbarns over the rival merits of French. While Reuben himself bought a photograph of Kitchener in a red, white, and blue frame. "The wife of a vassal would not have taste enough to buy such as these; and there is but one about Winchcombe who could work so well. And, by my faith, I now remember that it was part of the tenure by which I some time since granted land, to present a pair of gloves.¡ªWas it not a fair-looking damsel, one Stephen Holgrave's wife, that brought them?" John Ball pressed on with the multitude; but the immediate proximity of the palace, where all was splendour and motion, was not to the liking of one who till that day had never even dreamed of such things as had now met his sight. His nerves were weak, and he felt irritated at the insolence with which the royal guards, and the pages of the nobles, drove back the populace. His body, too, was weak, and he felt exhausted with his long and fatiguing walk: slowly and sadly he at length retraced his steps to his humble dwelling in the Minories. HoMEÐÂÏÊÏã·¹µê¾©´ó·µêµç»° ENTER NUMBET 0016www.fqchain.com.cn