CONTROVERSA LEGATA DE HIBRIZII OM-ANIMAL INCINGE SPIRITELE. Animal-Human Hybrids Spark Controversy

 

Oamenii de stiinta au inceput sa treaca linia de demarcatie dintre animale si oameni, prin producerea unor himere – creaturi hibride care sunt partial oameni, partial animale.

Cercetatori  chinezi de la Universitatea de Medicina din Shanghai, au fuzionat cu succes celule umane cu ovule de iepure. Embrionii au fost, dupa cum s-a relatat, primele himere om-animal create cu succes. Ei au fost lasati sa se dezvolte pentru mai multe zile intr-un vas de laborator, inainte ca oamenii de a fi distrusi pentru a recolta celule stem.

In Minnesota, cercetatorii de la Clinica Mayo au creat porci cu sange uman in sistemul lor circulator.Si la Universitatea Stanford din California se fac  experimente pentru a crea soareci cu creier uman.Unii oameni de stiinta sunt de parere ca, cu cat arata animalele  vor fi apropiate mai mult de uman, cu atat vor fi mai apte pentru testarea medicamentelor sau pentru producerea unor „piese de schimb’’, precum ficatul, in vederea transplantarii la oameni.

Urmarirea modului in care celulele umane se maturizeaza si interactioneaza intr-o creatura vie, ar putea duce de asemenea la descoperirea de noi tratemente medicale.Cu toate acestea, crearea unor  himere om-animal – numite asa dupa un monstru in mitologia greaca inchipuit a avea  cap de leu, trup de capra, si coada de sarpe, ridica  intrebari ingrijoratoare legate de cat de departe se poate merge cu astfel  de combinatii subumane  si in ce scop.

In ce conditii acestea pot fi  considerate umane si ce drepturi (daca ar fi vreunul), ar trebui sa aiba?In prezent nu exista legi federale in S.U.A care sa abordeze astfel de  probleme.

Orientari etice

Academia Nationala de Stiinte, care consiliaza  guvernul american, a studiat aceasta problema. Academia intentioneaza sa prezinte orientari voluntare etice pentru cercetatori.O himera este o combinatie din doua sau mai multe specii, intr-un singur trup.

Nu toate sunt totusi ingrijoratoare.De exemplu, valvele cardiace umane bolnave  sunt de obicei inlocuite cu cele prelevate de la vaci si porci. Chirurgia – care face astfel din primitor o himera om-animal este acum larg acceptata.

De ani de zile oamenii de stiinta au adaugat gene umane unor bacterii si animalelor de ferma.Ce a provocat scandal este insa amestecul de celule stem umane cu celule embrionare animale, pentru a crea noi specii.Activistul in biotehnologie Jeremy Rifkin se opune depasirii granitelor  dintre specii, deoarece  considera ca animalele au dreptul de a exista fara a fi falsificate sau incrucisate cu alte specii.

El recunoaste ca aceste studii ar putea duce la unele descoperiri medicale si cu toate acestea ele  totusi  nu ar trebui facute.„Exista si alte modalitati pentru a avansa in domeniul medicinei si sanatatii umane, fara a intra in ciudata  lume noua a  animalelor himerice’’, a spus Rifkin, adaugand ca modele sofisticate de calculator se pot substitui experimentarii pe animale vii.„Cineva nu trebuie sa fie religios sau militant pentru drepturile animalelor, pentru a gandi ca asa ceva nu are sens’’ a continuat el.

„Oamenii de stiinta sunt cei care e vor sa faca aceste experimente. Au intrecut masura, intrand in  domeniul patologic.’’David Magnus, director al Centrului Stanford pentru etica biomedicala la Universitatea Stanford, crede ca adevaratul motiv de  ingrijorare este legat de posibilitatea ca himerele sa fie intrebunitate in scopuri  problematice, riscante sau periculoase.Oameni nascuti din parinti soareciDe exemplu, un experiment care ar provoca ingrijorari, a spus el, este ingineria genetica pe soareci.

Spre exemplu insamantarea cu sperma umana a soarecilor ar conduce la aparitia unor embrioni si a unor copii cu parinti soareci…

 Canada a aprobat deja o  lege a Reproducerii Umane Asistate, care interzice himerele.

 Concret, acesta interzice transferarea unei celule neumane intr-un embrion uman si punerea celulelor umane intr-un embrion neuman.Cynthia Cohen este membra a Comitetului de Supraveghere pentru Celule Stem din Canada, care supervizeaza protocoalele de cercetare pentru a se asigura ca acestea sunt in conformitate cu noile orientari.

Ea considera ca o interdictie asemanatoare ar trebui sa existe  de asemenea si in USA.Crearea de himere, a spus ea, prin amestecarea gametilor  umani si animali (sperma si ovare) sau transferarea celulelor reproductive, diminueaza demnitatea umana.

„Aceasta ar nega ca exista ceva distinctiv si valors la fiintele si care ar trebui sa fie onorat si respectat’’, a spus Cohen, care este de asemenea cercetator principal la Institutul de Etica Kennedy al Universitatii Georgetown din Washington, D.C.Dar, a mentionat ea, modul de redactare a unei astfel de interdictii trebuie sa fie manifestat cu mare atentie.

 Totusi,  nu ar trebui sa fie scoase in afara legii experimentele etice si legitime – cum ar fi transferul unui numar limitat de celule stem adulte umane in embioni de animale, in scopul de a afla modul in care acestea prolifereaza si cresc in perioada prenatala.

Irv Weissman, director la Institutul de Cancer al Universitatii Stanford / Biologia Celulelor Stem si Medicina din California, este impotriva unei interdictii in Statele Unite.

„Oricine isi pune propriile orientari morale in calea stiintei biomedicale, in cazul in care   doresc sa-si impuna dorintele – nu doar ca parte a unuei argumentatii – daca asta duce la o interdictie sau moratoriu…impiedica  cercetari ce ar putea salva vieti umane’’ a spus el.Soareci cu creier umanWeissman a creat deja soareci cu creieri care sunt 1% umani.

In cursul acestui an el ar putea efectua un alt experiment in care soarecii vor avea creierul 100% umani. Acest lucru s-ar face, a spus el, prin injectarea de neuroni umani in creierul embrionului de soarece.Inainte de a se naste soarecii vor fi ucisi si disecati pentru a se vedea daca s-a format structura unui creier uman .

                   

Weissman a spus ca nu este un om de stiinta nebun care incearca sa creeze un om in trup de animal. El spera ca experimentul va conduce la o mai buna intelegere a modului in care creierul functioneaza fapt  care ar fi util in tratarea unor boli precum Alzheimer sau boala Parkinson.Testul inca nu a fost inceput. Weissman asteapta sa citeasca raportul Academiei Nationale .William Cheshire, profesor asociat de neurologie la Clinica Mayo in Jacksonville, Florida, considera ca,trecerea la  combinarea neuronilor umani cu cei animali este problematica.„Acesta este un teritoriu biologic neexplorat,’’ a spus el.

„Oricare ar fi pragul de moralitate a dezvoltarii neurale umane pe care l-am alege pentru a seta ca limita pentru un astfel de experiment, exista un risc considerabil de depasire a acelei limite, inainte de a o putea cunoaste”.Cheshire sprijina cercetarea care combina celule umane si animale pentru a studia functia celulara. Ca student el a participat la cercetari in cadrul careia s-au fuzionat celulele umane cu cele de soarece.

„Trebuie sa fim atenti sa nu incalcam integritatea umanitatii sau a vietii animale pentru care avem o responsabilitatea de a le proteja”, a spus Cheshire, membru al Asociatilor Crestin Medicale si Dentare. „Proiecte de cercetare care creaza himere om-animal risca sa perturbe ecosistemele fragile, pun in pericol sanatatea, si afecteaza integritatea speciilor.’’

Animal-Human Hybrids Spark Controversy

 

Scientists have begun blurring the line between human and animal by producing chimeras—a hybrid creature that’s part human, part animal.Chinese scientists at the Shanghai Second Medical University in 2003 successfully fused human cells with rabbit eggs. The embryos were reportedly the first human-animal chimeras successfully created. They were allowed to develop for several days in a laboratory dish before the scientists destroyed the embryos to harvest their stem cells. In Minnesota last year researchers at the Mayo Clinic created pigs with human blood flowing through their bodies.And at Stanford University in California an experiment might be done later this year to create mice with human brains.Scientists feel that, the more humanlike the animal, the better research model it makes for testing drugs or possibly growing „spare parts,” such as livers, to transplant into humans.Watching how human cells mature and interact in a living creature may also lead to the discoveries of new medical treatments.But creating human-animal chimeras—named after a monster in Greek mythology that had a lion’s head, goat’s body, and serpent’s tail—has raised troubling questions: What new subhuman combination should be produced and for what purpose? At what point would it be considered human? And what rights, if any, should it have?There are currently no U.S. federal laws that address these issues.Ethical GuidelinesThe National Academy of Sciences, which advises the U.S. government, has been studying the issue.

In March it plans to present voluntary ethical guidelines for researchers.A chimera is a mixture of two or more species in one body. Not all are considered troubling, though.For example, faulty human heart valves are routinely replaced with ones taken from cows and pigs. The surgery—which makes the recipient a human-animal chimera—is widely accepted. And for years scientists have added human genes to bacteria and farm animals.

What’s caused the uproar is the mixing of human stem cells with embryonic animals to create new species.

Biotechnology activist Jeremy Rifkin is opposed to crossing species boundaries, because he believes animals have the right to exist without being tampered with or crossed with another species.

He concedes that these studies would lead to some medical breakthroughs. Still, they should not be done.

„There are other ways to advance medicine and human health besides going out into the strange, brave new world of chimeric animals,” Rifkin said, adding that sophisticated computer models can substitute for experimentation on live animals.

„One doesn’t have to be religious or into animal rights to think this doesn’t make sense,” he continued. „It’s the scientists who want to do this. They’ve now gone over the edge into the pathological domain.”

David Magnus, director of the Stanford Center for Biomedical Ethics at Stanford University, believes the real worry is whether or not chimeras will be put to uses that are problematic, risky, or dangerous.

Human Born to Mice Parents?

For example, an experiment that would raise concerns, he said, is genetically engineering mice to produce human sperm and eggs, then doing in vitro fertilization to produce a child whose parents are a pair of mice.

„Most people would find that problematic,” Magnus said, „but those uses are bizarre and not, to the best of my knowledge, anything that anybody is remotely contemplating. Most uses of chimeras are actually much more relevant to practical concerns.”

Last year Canada passed the Assisted Human Reproduction Act, which bans chimeras. Specifically, it prohibits transferring a nonhuman cell into a human embryo and putting human cells into a nonhuman embryo.

Cynthia Cohen is a member of Canada’s Stem Cell Oversight Committee, which oversees research protocols to ensure they are in accordance with the new guidelines.

She believes a ban should also be put into place in the U.S.

Creating chimeras, she said, by mixing human and animal gametes (sperms and eggs) or transferring reproductive cells, diminishes human dignity.

„It would deny that there is something distinctive and valuable about human beings that ought to be honored and protected,” said Cohen, who is also the senior research fellow at Georgetown University’s Kennedy Institute of Ethics in Washington, D.C.

But, she noted, the wording on such a ban needs to be developed carefully. It shouldn’t outlaw ethical and legitimate experiments—such as transferring a limited number of adult human stem cells into animal embryos in order to learn how they proliferate and grow during the prenatal period.

Irv Weissman, director of Stanford University’s Institute of Cancer/Stem Cell Biology and Medicine in California, is against a ban in the United States.

„Anybody who puts their own moral guidance in the way of this biomedical science, where they want to impose their will—not just be part of an argument—if that leads to a ban or moratorium. … they are stopping research that would save human lives,” he said.

Mice With Human Brains

Weissman has already created mice with brains that are about one percent human.

Later this year he may conduct another experiment where the mice have 100 percent human brains. This would be done, he said, by injecting human neurons into the brains of embryonic mice.

Before being born, the mice would be killed and dissected to see if the architecture of a human brain had formed. If it did, he’d look for traces of human cognitive behavior.

Weissman said he’s not a mad scientist trying to create a human in an animal body. He hopes the experiment leads to a better understanding of how the brain works, which would be useful in treating diseases like Alzheimer’s or Parkinson’s disease.

The test has not yet begun. Weissman is waiting to read the National Academy’s report, due out in March.

William Cheshire, associate professor of neurology at the Mayo Clinic’s Jacksonville, Florida, branch, feels that combining human and animal neurons is problematic.

„This is unexplored biologic territory,” he said. „Whatever moral threshold of human neural development we might choose to set as the limit for such an experiment, there would be a considerable risk of exceeding that limit before it could be recognized.”

Cheshire supports research that combines human and animal cells to study cellular function. As an undergraduate he participated in research that fused human and mouse cells.

But where he draws the ethical line is on research that would destroy a human embryo to obtain cells, or research that would create an organism that is partly human and partly animal.

„We must be cautious not to violate the integrity of humanity or of animal life over which we have a stewardship responsibility,” said Cheshire, a member of Christian Medical and Dental Associations. „Research projects that create human-animal chimeras risk disturbing fragile ecosystems, endanger health, and affront species integrity.”

Maryann Mott
National Geographic News

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VIDEO SI FOTO: CEL MAI URAT CAINE DIN LUME

Are un singur ochi ,trei picioare si e in China. A  fost încoronat „Cel mai urât caine din lume” 

 

Documente dezvaluite de Wikileaks releva uimitoare progrese ale Chinei in fuziunea nucleara si in teleportare .Wikileaked Cables from Beijing Reveal China’s Pursuit of Fusion Power, Teleportation

The University of Science and Technology of China Minbali via Wikimedia

Universitatea de Ştiinţă şi Tehnologie din China Minbali prin Wikimedia

Nu mai este nici un secret faptul că China incepe sa depaseasca America şi Occidentul , în numeroase domenii dar  ştiril e exacte despre  ce se intampla acolo sunt  adesea limitate. Săptămâna trecută in telegramele secrete  provenite de la  ambasada americana din Beijing  Wikileaks, a aruncat o  lumină privind  paşii pe oamenii de stiinta chinezi i-au facut în domenii cum ar fi fisiunea nucleară, datele biometrice, şi chiar in teleportare.

Telegrame confidenţiale diplomatice trimise de Ambasada americana din  Beijing la Washington în luna februarie sugerează ca China estein plin progres stiintific si isi  extinde agresiv resursele  în domeniul energiei nucleare, avand planuri de a deschide cel puţin 70 de centrale nucleare în următorii zece ani. Mai interesant, Academia Chineza de Stiinte (CAS) are o  finanţare a cercetării în Institutul de Fizica plasmei (IPP) pentru a desfăşura activităţi de cercetare de varf în fuziunea nucleară.

China a luat, deja, un avans important in fata statelor occidentale si a SUA, in ceea ce priveste investitiile in infrastructura si tehnologii futuriste.

Pana in prezent, nu se stia, cu exactitate, nivelul la care au ajuns chinezii in aceste domenii de maxima importanta. Astazi, dupa publicarea pe Wikileaks a documentelor care privesc China, o intreaga lume afla cu stupoare ca ea  a facut pasi importanti  in domenii precum fisiunea nucleara, biometrie si chiar teleportarea fizica!

Conform unei telegrame secrete, Academia Chineza de Stiinte dispune de fonduri nelimitate pentru sustinerea cercetarilor de la Institutul de Fizica al Plasmei,care este angajat in cercetari fara precedent in privinta fuziunii nucleare. 

Se pare ca, China lucreaza la un nou reactor, intitulat Experimental Advanced Superconducting Tokamak. In acest reactor, savantii chinezi spera sa obtina o fuziune nucleara controlata care sa mentina nedefinit o temperatura extrema.

In anul 2009, cercetatorii chinezi au reusit sa mentina o reactie nucleara care atinsese temperatura de 18 milioane grade Celsius, pana la 400 de secunde, dupa ce anterior mentinusera, timp de 60 de seunde, o reactie nucleara de 180 milioane grade Celsius.

Pe parcursul acestui an, chinezii si-au propus sa obtina temperatura de 180 milioane grade Celsius, mentinuta timp de 400 secunde; spre disperarea lor, serviciile secrete americane nu au reusit sa afle daca asiaticii au reusit acesta performanta, conform documentelor publicate de Wikileaks.

China face pasi uriasi si spre celebrele operatiuni de teleportare: conform unui oficial al Universitatii de Stiinte si Tehnologii din orasul Hefei, savantii chinezi ar fi reusit teleportarea cu succes a unei singure particule quantum, iar in prezent lucreaza la teleportarea a doua particule.

Institutul de Tehnologii Inteligente din China nu se lasa mai prejos, reusind crearea unui sistem biometric care identifica persoanele in functie de trasaturi faciale, greutate si proportii corporale. Device-ul futurist iti citeste toate datele antropometrice intr-o fractiune de secunda

Wikileaked Cables from Beijing Reveal China’s Pursuit of Fusion Power, Teleportation

 

The University of Science and Technology of China Minbali via Wikimedia

It’s no secret that China is beating up on America and the West in everything from infrastructure to technology investment, but news of exactly what the People’s Republic is up to is often scarce.

So while the diplomatic establishment continues to reel from the stink of its own dirty laundry in last week’s Wikileaks document dump, cables coming from the American Embassy in Beijing are also shedding light on the strides Chinese scientists are making in far-out fields like nuclear fission, biometrics, and even quantum teleportation.

One confidential diplomatic cable sent from the Beijing Embassy to Washington in February suggests China is doing big things at the small scale.

For one, China is aggressively expanding its nuclear energy resources, with plans to open at least 70 nuclear plants in the next decade. More interestingly, the Chinese Academy of Sciences (CAS) is pouring research funding into its Institute of Plasma Physics (IPP) to conduct ongoing research into nuclear fusion.

Apparently China has been hard at work on its Experimental Advanced Superconducting Tokamak (EAST) reactor, which is designed to sustain a controlled fusion reaction that can go on indefinitely at high temperatures. In 2009, researchers apparently sustained a 18-million-degree reaction for 400 seconds, and a 180-million-degree reaction for 60 seconds.

Their goal for 2010 was to sustain a 180-million-degree reaction for more than 400 seconds, though it’s unclear if they achieved that. Moreover, IPP is apparently conducting research on hybrid fission-fusion reactors, though details are slim.

Perhaps most interesting: China doubled the IPP budget in 2009 over 2008, and the diplomatic chatter suggests 2010’s budget saw a significant boost as well. Amid choppy economic waters, such funding bumps indicate a real commitment on China’s part to figure out the fusion energy puzzle.

China’s sci-tech ambitions don’t stop there. While the evidence is anecdotal, the embassy seems to think the Chinese are pulling ahead in fields like quantum communications and even teleportation.

To quote one diplomat’s description of a trip to the University of Science and Technology of China (USTC) in Hefei: “A cursory walk through their labs seemed to indicate they had already succeeded in single-particle quantum teleportation and are now trying to conduct dual-particle quantum teleportation.”

Then there’s the Big Brother tech that we’ve come to expect from China. The same cable says the CAS’s Institute of Intelligent Machines (IIM) in Hefei has created a biometric system that identifies individuals through their pace and gait.

“The device measure weight and two-dimensional sheer forces applied by a person’s foot during walking to create a uniquely identifiable biometrics profile,” the cable says, and can be installed covertly in a floor to surreptitiously collect biometric data.

Source: PopSci

[Wikileaks]

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