first_imgBackgrounder: Clues to a Chemical Weapons Attack in SyriaThe United States is weighing a military strike against Syria after concluding that Syrian President Bashar al-Assad is responsible for an “undeniable” chemical attack that killed hundreds of people. This week, U.N. investigators are interviewing survivors and collecting samples in the area near Damascus where the 21 August attack allegedly occurred. Judging from videos and other accounts of the attack, chemical weapons specialists say that the investigators are likely to focus on suspicions that the attack involved the nerve agent sarin. But why do experts suspect sarin? And what exactly are investigators looking for? ScienceInsider lays out what we know—and what we’re looking for.Babies Learn to Recognize Words in the WombSign up for our daily newsletterGet more great content like this delivered right to you!Country *AfghanistanAland IslandsAlbaniaAlgeriaAndorraAngolaAnguillaAntarcticaAntigua and BarbudaArgentinaArmeniaArubaAustraliaAustriaAzerbaijanBahamasBahrainBangladeshBarbadosBelarusBelgiumBelizeBeninBermudaBhutanBolivia, Plurinational State ofBonaire, Sint Eustatius and SabaBosnia and HerzegovinaBotswanaBouvet IslandBrazilBritish Indian Ocean TerritoryBrunei DarussalamBulgariaBurkina FasoBurundiCambodiaCameroonCanadaCape VerdeCayman IslandsCentral African RepublicChadChileChinaChristmas IslandCocos (Keeling) IslandsColombiaComorosCongoCongo, The Democratic Republic of theCook IslandsCosta RicaCote D’IvoireCroatiaCubaCuraçaoCyprusCzech RepublicDenmarkDjiboutiDominicaDominican RepublicEcuadorEgyptEl SalvadorEquatorial GuineaEritreaEstoniaEthiopiaFalkland Islands (Malvinas)Faroe IslandsFijiFinlandFranceFrench GuianaFrench PolynesiaFrench Southern TerritoriesGabonGambiaGeorgiaGermanyGhanaGibraltarGreeceGreenlandGrenadaGuadeloupeGuatemalaGuernseyGuineaGuinea-BissauGuyanaHaitiHeard Island and Mcdonald IslandsHoly See (Vatican City State)HondurasHong KongHungaryIcelandIndiaIndonesiaIran, Islamic Republic ofIraqIrelandIsle of ManIsraelItalyJamaicaJapanJerseyJordanKazakhstanKenyaKiribatiKorea, Democratic People’s Republic ofKorea, Republic ofKuwaitKyrgyzstanLao People’s Democratic RepublicLatviaLebanonLesothoLiberiaLibyan Arab JamahiriyaLiechtensteinLithuaniaLuxembourgMacaoMacedonia, The Former Yugoslav Republic ofMadagascarMalawiMalaysiaMaldivesMaliMaltaMartiniqueMauritaniaMauritiusMayotteMexicoMoldova, Republic ofMonacoMongoliaMontenegroMontserratMoroccoMozambiqueMyanmarNamibiaNauruNepalNetherlandsNew CaledoniaNew ZealandNicaraguaNigerNigeriaNiueNorfolk IslandNorwayOmanPakistanPalestinianPanamaPapua New GuineaParaguayPeruPhilippinesPitcairnPolandPortugalQatarReunionRomaniaRussian FederationRWANDASaint Barthélemy Saint Helena, Ascension and Tristan da CunhaSaint Kitts and NevisSaint LuciaSaint Martin (French part)Saint Pierre and MiquelonSaint Vincent and the GrenadinesSamoaSan MarinoSao Tome and PrincipeSaudi ArabiaSenegalSerbiaSeychellesSierra LeoneSingaporeSint Maarten (Dutch part)SlovakiaSloveniaSolomon IslandsSomaliaSouth AfricaSouth Georgia and the South Sandwich IslandsSouth SudanSpainSri LankaSudanSurinameSvalbard and Jan MayenSwazilandSwedenSwitzerlandSyrian Arab RepublicTaiwanTajikistanTanzania, United Republic ofThailandTimor-LesteTogoTokelauTongaTrinidad and TobagoTunisiaTurkeyTurkmenistanTurks and Caicos IslandsTuvaluUgandaUkraineUnited Arab EmiratesUnited KingdomUnited StatesUruguayUzbekistanVanuatuVenezuela, Bolivarian Republic ofVietnamVirgin Islands, BritishWallis and FutunaWestern SaharaYemenZambiaZimbabweI also wish to receive emails from AAAS/Science and Science advertisers, including information on products, services and special offers which may include but are not limited to news, careers information & upcoming events.Required fields are included by an asterisk(*)Be careful what you say around a pregnant woman, at least in the last trimester. As a fetus grows inside a mother’s belly, it can hear sounds from the outside world—and can understand them well enough to retain memories of them after birth, according to new research.RNAi Treatment Steps UpRNA interference (RNAi), a technique for silencing genes that shows potential for treating diseases, has been like a hot baseball prospect who hasn’t proven he can play in the big leagues. But now RNAi has turned in a performance that is winning researchers’ praise. A new study shows that the approach can dramatically and safely cut levels of a protein that causes a rare liver disease.Measleslike Virus Likely Culprit in U.S. Dolphin Die-OffDead dolphins have been recovered from the Eastern Seaboard at a rate that is 10 times higher than usual—333 since just 1 July. This week, researchers announced the culprit is an outbreak of a measleslike virus. They say the epidemic will continue until the number of susceptible animals dwindles, and that there is no feasible way to vaccinate or treat the animals.Memory Protein Fades With AgeIt’s an inconvenient truth of aging: As we get older, our memories get worse. But is this memory loss an early form of Alzheimer’s or something else entirely? Now, scientists have found a protein that declines as we get older and distinguishes typical age-related forgetfulness from Alzheimer’s. The discovery could lead to treatment for run-of-the-mill memory loss.last_img

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first_imgRajasthan Chief Minister Vasundhara Raje on Saturday embarked on a 58-day-long ‘Gaurav Yatra’ (march of pride) from the Charbhujanath Temple in the Rajsamand district, with an eye on the State Assembly election due in December this year. Bharatiya Janata Party (BJP) president Amit Shah launched a scathing attack on Congress president Rahul Gandhi while flagging off the yatra.Daily questionPradesh Congress president Sachin Pilot, who has announced that he would pose one question to Ms. Raje everyday during the yatra, asked whether the BJP wanted to use temples only for getting political mileage in the elections. Congress workers also staged a protest against the yatra in Jaipur and burnt Ms. Raje’s effigy at the District Collectorate.Ms. Raje and Mr. Shah offered prayers at the temple before heading to Kankroli town where they addressed the first public meeting of the much-hyped yatra. Ms. Raje will use a modified bus as the ‘chariot’ during the onward journey, in which she will cover 165 of the 200 Assembly constituencies in the State by spending 40 days on the road. The march will culminate in Ajmer on September 30.Mr. Shah public wanted to know from Mr. Gandhi what his “last four generations” had done for the country. “There was a complete lack of development in a State like Rajasthan during the Congress rule,” he said.The BJP president claimed that the National Democratic Alliance (NDA) government had released two-and-a-half-times more funds to Rajasthan in comparison with the previous UPA regime and brought 116 schemes for the people of the State. “Still, the Congress has the audacity to ask what the BJP has done [for you],” he told the audience drawn from the Mewar region.Mr. Shah also raked up the issue of Assam’s National Register of Citizens (NRC), while alleging that Congress wanted to exploit the “illegal Bangladeshis” residing in India as its vote bank. “The Congress president should tell the people if Bangladeshis should continue to live in our country,” he said, and affirmed that the NDA government would “weed out every foreign national living illegally in India.”Taking strong exception to the tone and tenor of Mr. Shah’s speech, Mr. Pilot said his remarks had damaged the dignity of politics and proved that the BJP had nothing to offer to the public.last_img

first_imgThe early signs of Creutzfeldt-Jakob disease (CJD)—a rare, incurable brain disorder caused by infectious, misshapen proteins called prions—are difficult to interpret. At first, people may simply feel depressed and can undergo personality changes or bouts of psychosis. By the time memory failure, blindness, and coma set in, typically within a year of infection, death is usually imminent. Now, researchers report that a simple nasal swab may help physicians detect the disease far more accurately and earlier than current methods.Finding simple, noninvasive diagnostic tests is “one of the holy grails” for CJD and other prion diseases, says biochemist Byron Caughey of the National Institute of Allergy and Infectious Diseases’ Rocky Mountain Laboratories in Hamilton, Montana, who helped lead the new work. Although there’s no cure for CJD, early diagnosis is important because it can help rule out other, treatable disorders, and it allows medical personnel to take precautions that prevent the disease from spreading to others through exposure to brain tissue or spinal fluid, he says. A type of the disease called variant CJD in humans results from eating meat infected with mad cow disease.Researchers made a major stride toward better diagnostic methods in 2010, when Caughey and other researchers first described a new technique called the RT-QuIC test. The test requires removing cerebrospinal fluid (CSF) from patients by means of a spinal tap, putting samples into a bath of normally shaped prion proteins, and agitating the solution to encourage any abnormal prion “seeds” in the tissue to latch onto the regular proteins. If even trace amounts of pathogenic protein are present, they rapidly use the normal proteins to create millions of insoluble, fibrous amyloid strands. Researchers believe that these amyloid aggregates, also seen in other neurodegenerative diseases such as Alzheimer’s disease, ultimately cause CJD by interfering with or killing off neurons en masse. After death, the brains of people affected by CJD are so badly damaged that they often resemble Swiss cheese or sponges.Sign up for our daily newsletterGet more great content like this delivered right to you!Country *AfghanistanAland IslandsAlbaniaAlgeriaAndorraAngolaAnguillaAntarcticaAntigua and BarbudaArgentinaArmeniaArubaAustraliaAustriaAzerbaijanBahamasBahrainBangladeshBarbadosBelarusBelgiumBelizeBeninBermudaBhutanBolivia, Plurinational State ofBonaire, Sint Eustatius and SabaBosnia and HerzegovinaBotswanaBouvet IslandBrazilBritish Indian Ocean TerritoryBrunei DarussalamBulgariaBurkina FasoBurundiCambodiaCameroonCanadaCape VerdeCayman IslandsCentral African RepublicChadChileChinaChristmas IslandCocos (Keeling) IslandsColombiaComorosCongoCongo, The Democratic Republic of theCook IslandsCosta RicaCote D’IvoireCroatiaCubaCuraçaoCyprusCzech RepublicDenmarkDjiboutiDominicaDominican RepublicEcuadorEgyptEl SalvadorEquatorial GuineaEritreaEstoniaEthiopiaFalkland Islands (Malvinas)Faroe IslandsFijiFinlandFranceFrench GuianaFrench PolynesiaFrench Southern TerritoriesGabonGambiaGeorgiaGermanyGhanaGibraltarGreeceGreenlandGrenadaGuadeloupeGuatemalaGuernseyGuineaGuinea-BissauGuyanaHaitiHeard Island and Mcdonald IslandsHoly See (Vatican City State)HondurasHong KongHungaryIcelandIndiaIndonesiaIran, Islamic Republic ofIraqIrelandIsle of ManIsraelItalyJamaicaJapanJerseyJordanKazakhstanKenyaKiribatiKorea, Democratic People’s Republic ofKorea, Republic ofKuwaitKyrgyzstanLao People’s Democratic RepublicLatviaLebanonLesothoLiberiaLibyan Arab JamahiriyaLiechtensteinLithuaniaLuxembourgMacaoMacedonia, The Former Yugoslav Republic ofMadagascarMalawiMalaysiaMaldivesMaliMaltaMartiniqueMauritaniaMauritiusMayotteMexicoMoldova, Republic ofMonacoMongoliaMontenegroMontserratMoroccoMozambiqueMyanmarNamibiaNauruNepalNetherlandsNew CaledoniaNew ZealandNicaraguaNigerNigeriaNiueNorfolk IslandNorwayOmanPakistanPalestinianPanamaPapua New GuineaParaguayPeruPhilippinesPitcairnPolandPortugalQatarReunionRomaniaRussian FederationRWANDASaint Barthélemy Saint Helena, Ascension and Tristan da CunhaSaint Kitts and NevisSaint LuciaSaint Martin (French part)Saint Pierre and MiquelonSaint Vincent and the GrenadinesSamoaSan MarinoSao Tome and PrincipeSaudi ArabiaSenegalSerbiaSeychellesSierra LeoneSingaporeSint Maarten (Dutch part)SlovakiaSloveniaSolomon IslandsSomaliaSouth AfricaSouth Georgia and the South Sandwich IslandsSouth SudanSpainSri LankaSudanSurinameSvalbard and Jan MayenSwazilandSwedenSwitzerlandSyrian Arab RepublicTaiwanTajikistanTanzania, United Republic ofThailandTimor-LesteTogoTokelauTongaTrinidad and TobagoTunisiaTurkeyTurkmenistanTurks and Caicos IslandsTuvaluUgandaUkraineUnited Arab EmiratesUnited KingdomUnited StatesUruguayUzbekistanVanuatuVenezuela, Bolivarian Republic ofVietnamVirgin Islands, BritishWallis and FutunaWestern SaharaYemenZambiaZimbabweI also wish to receive emails from AAAS/Science and Science advertisers, including information on products, services and special offers which may include but are not limited to news, careers information & upcoming events.Required fields are included by an asterisk(*)The RT-QuIC test, now being used in diagnostic centers around the world, works well but still misses about 10% to 20% of cases, Caughey says. It also requires an invasive, potentially painful spinal tap. In the new study, the researchers ran a fiber optic scope straight up patients’ noses to the very top of the nasal cavity where olfactory neurons are located. In theory, these neurons should contain much higher levels of abnormal prion protein tangles than does CSF because they are directly connected to the brain, Caughey notes. Then, the scientists rolled a small brush along the roof of the nasal vault and analyzed the samples of discharge or tissue they collected with the RT-QuIC assay.As predicted, the concentration of abnormal prions detected in the nasal samples was several orders of magnitude higher than those found in CSF, the group reports online today in The New England Journal of Medicine (NEJM). Compared with the CSF-based method, which correctly identified only about 77% of positive cases in this study, the swab test caught 97% of 30 CJD-positive patients, missing just one. In addition, the nasal brushings produced no false negative results in 45 disease-free controls, Caughey says.“Much higher numbers of patients and controls need to be tested to work out the actual diagnostic sensitivity” of the test, but it appears to be a promising way of detecting CJD without performing an invasive procedure, Caughey says. One of his colleagues underwent the nasal brush test, he says, and although it was not exactly a pleasant experience, “there’s not much pain involved, apparently.”“This is a big advance,” says Pierluigi Gambetti, a neuropathologist at Case Western Reserve University in Cleveland, Ohio. In principle, the nasal brush test should make it possible to diagnose the disorder much earlier than the CSF–based technique because abnormal prions build up in olfactory neurons more quickly than they migrate out of the brain into spinal fluid, he says.Gambetti, who was not involved in the new study, is co-author on a second NEJM paper appearing online today that shows that an assay similar to the CSF–based RT-QuIC test can pick up very small amounts of abnormal prion protein in the urine of people who have contracted a rare variant of CJD that is transmitted by consuming contaminated meat. A handful of such cases have recently been diagnosed in the United States, he notes, and the urine test could be another quick, affordable way to screen for the disease.Although these new diagnostic methods may help prevent CJD from spreading, they can do little for patients themselves, Caughey says. “Hopefully someday we’ll have a therapy” so that clinicians can intervene before too much damage is done.last_img

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