Quenzer Bryce

xiaoming · Dołączył: 19 Cze 2017 Posty: 371

"
SAN FRANCISCO Cheap Klim Kostin Jersey , March 17 (Xinhua) -- In what could lead to contraceptives that work in both men and women, researchers at University of California, Berkeley, have identified a protein receptor on the surface of sperms that responds to the female sex hormone progesterone.

Describing the receptor as a switch, or a trigger, the researchers said it is the key to the ""power kick"" needed by a sperm to penetrate and fertilize a human egg.

""If the receptor protein doesn't recognize progesterone Cheap Robert Thomas Jersey , you would be infertile,"" said Melissa Miller, a postdoctoral fellow at both UC Berkeley and University of California, San Francisco, and the first author of a paper published on Thursday in the ""Fast Release"" issue of the journal Science.

Progesterone is released by the egg or oocyte, the ultimate goal toward which sperm swim. When the sperm gets close to the egg Cheap Tage Thompson Jersey , the hormone activates the receptor and triggers a cascade of changes that make the tail snap like a whip, powering the sperm into and hopefully through the cells protecting the egg.

The receptor ""gives us an understanding of another pathway that is involved in human sperm activity,"" Miller said, adding that ""what's really cool is that we have an actual target for unisex contraceptive development.""

""If you can stop progesterone from inducing a power stroke, sperm are not going to be able to reach or penetrate the oocyte,"" she explained.

The new discovery has also uncovered a possible source of male infertility Cheap Vince Dunn Jersey , as sperm may be to blame in half of all cases of infertile couples, while doctors currently are unable to determine the cause of nearly 80 percent of all cases of male infertility.

In their lab work, techniques that Polina Lishko, a UC Berkeley assistant professor of molecular and cell biology, and her colleague Yuriy Kirichok developed over the past five years at UCSF and UC Berkeley were used, allowing them to stick electrodes on a sperm's tail and record its reactions to hormones.

That led to their discovery that a large receptor on sperm tails -- a calcium channel dubbed CatSper -- is activated by progesterone from the egg. Progesterone unlocks the channel gate Cheap Chris Thorburn Jersey , letting electrically charged calcium atoms flood into the cell, leading to a biochemical cascade that readies the sperm cell for its last-ditch effort to fertilize the oocyte.

Miller and Lishko, senior author of the paper, suspected that progesterone was not acting directly on the calcium channel, but on some other receptor that activated the calcium channel.

The team did confirm that progesterone actually binds to a previously mysterious enzyme called ABHD2, which is found at high levels in sperm. Once progesterone binds to the enzyme Cheap Patrik Berglund Jersey , which sits on the surface of the sperm, it removes a lipid (2AG) that has been inhibiting the calcium channel. Released of inhibition, CatSper opens the gate to calcium ions and eventual sperm activation.

The inhibitor of CatSper is probably there for a good reason: to prevent sperm from prematurely sprinting toward the egg and using up their limited supply of energy, Miller said.

" Of late, Water pond or a fish pond has emerged as a design element for backyards. These projects, however Cheap Jay Bouwmeester Jersey , can only be achieved in sprawling and huge yards that has walkways and large areas.

But if you are determined to put up your own fish pond and yet you do not have a large back yard, you can try out certain design techniques to achieve your goal without giving up much land portion and dominate your yard.

You can make the overall design of your backyard revolve around the fishpond. Place it in the middle or in one corner of the yard if you have a small space. It should have a eye-catching look.

If you wish to place it in the corner part of the
yard, raise the pond a little higher so that the fish will seem as a surprise to the visitors. But if you want to place it in the center, it is best if you place the pond at ground level or a little above it.

Choose fish properly so as to get enough attention. Watching the fishes swim around everyday can also serve to be therapeutic. Remember that large fish like Koi are not suitable for small sized fishponds. They may not live long in this kind of environment and they are also extremely expensive. Goldfish are compatible with the size of your pond, however, their longevity might not be a guaranteed in an outdoor pond.

Think how much you really want an outdoor pond and how you can maintain and build it depending on your preferences. You might find that maintaining an indoor aquarium is difficult enough Cheap Robby Fabbri Jersey , how much more an outdoor pond.

Tropical weather conditions,mainly availability of sunshine all through the year is most suited for water ponds and fish ponds. A few types of aquatic plants will grow properly when given sun rays. As against that, winters spell doom for plants as fishes when exposed to water. It is best to transfer them to an indoor tank if the weather is not applicable.

A fish pond in your own backyard only tells an individual how much energy, time, and money you are willing to devote to the beautification of your backyard. It does not matter how large or how small it is, it just goes to show that you appreciate beautiful things. You will not only impress a lot of people but yourself as well. A back yard fish pond changes the whole appearance of the place Cheap Zach Sanford Jersey , giving it a polished and exuberant look.

In order to make your fish pond more appealing, decorate its surroundings. You can achieve a natural feel by using landscaping ideas to attract birds and frogs. If landscaping i beyond budget for the moment, you can use hangings and flowered bushes. This will produce a great ambiance to your visitors and guests.

Having a fish pond is not a go-get-it-and-have-it project. It requires continuous action in terms . Cheap Air Force 1 White Cheap Air Force 1 Low Cheap Air Force 1 Wheat Cheap Nike Air Force 1 Cheap Nike Air Force 1 High Cheap Nike Air Force 1 Black Cheap Air Vapormax For Sale Cheap Nike Air Vapormax Cheap Air Vapormax Mens Cheap Air Vapormax Red