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Transgena primater

Inlägg av Tryggve » tor 07 nov 2013, 18:06

Teknik- och metodutvekling har öppnat för möjligheten att skapa transgena primater. Dessa skulle kunna vara till stor nytta för läkemedelsforskning.

Precision gene editing paves way for transgenic monkeys
Precision gene editing paves way for transgenic monkeys

Despite political challenges, engineered primates could be better disease models than mice.

Anthony Chan spent two years creating the first five monkeys in the world to be genetically engineered with human mutations — in this case, for Huntington’s disease. But three of the five monkeys, reported in 2008, developed severe symptoms of Huntington’s much more quickly than anticipated, and had to be killed within a month of birth1. Viruses used to introduce the relevant gene had inserted extra copies randomly, intensifying the symptoms — and highlighting the method’s limitations in creating animal disease models.

Chan, a geneticist at Emory University in Atlanta, Georgia, and other scientists around the world are now eyeing precision genome-editing techniques that solve such problems by using enzymes and RNA instead of viruses. Many have high hopes that transgenic monkeys will mimic human genetic conditions more faithfully than mice — and thus permit better drug-development tests. Many also say that the primates will accelerate basic research in neuro­science, permitting researchers to map and test complex neural circuits underlying behaviours that do not exist in simpler organisms. “We weren’t even able to think about this before,” says Chan.

Work is already under way in a few labs. Erika Sasaki, a geneticist at Keio University in Tokyo, was part of the team that used viruses to produce the first transgenic marmoset to pass on an engineered gene to its offspring2. On 11 November, at the annual meeting of the Society for Neuro­science in San Diego, California, Sasaki and her colleagues will present efforts to model autistic behaviour in marmosets using mutations produced with zinc-finger nucleases — a class of DNA-cutting enzyme. Next month, the Salk Institute for Biological Studies in La Jolla, California, is hosting a workshop to bring together molecular biologists, bioengineers and neuroscientists to work on challenges in the field. “This is something with tremendous potential,” says Terrence Sejnowski, head of the computational neurobiology laboratory at the Salk Institute.

Neuroscientists have long wanted transgenic monkeys. Disorders such as autism, schizophrenia and Alzheimer’s disease cannot be fully replicated in mice, which lack the complex cognitive and social abilities of primates. More­over, many neuroactive drugs that showed early promise in mice have failed in human trials.

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Växtsignalering

Inlägg av Tryggve » fre 08 nov 2013, 16:00

För en tid sedan så var jag på ett seminarium där det presenterades rätt intressanta resultat om signalering i växter. Nu är detta publicerat, så nu kan jag väl nämna det här med gott samvete, antar jag... :-)
Detta är inte med i Nature News vad jag har sett, (även om det borde vara det, för det är väldigt intressant, men det kanske kommer) så det är rätt nischat. Man har alltså fått fram resultat som indikerar att det faktiskt sker signalering via elektriska signaler i växter.
http://www.nature.com/nature/journal/v5 ... 12478.html
GLUTAMATE RECEPTOR-LIKE genes mediate leaf-to-leaf wound signalling

Wounded leaves communicate their damage status to one another through a poorly understood process of long-distance signalling. This stimulates the distal production of jasmonates, potent regulators of defence responses. Using non-invasive electrodes we mapped surface potential changes in Arabidopsis thaliana after wounding leaf eight and found that membrane depolarizations correlated with jasmonate signalling domains in undamaged leaves. Furthermore, current injection elicited jasmonoyl-isoleucine accumulation, resulting in a transcriptome enriched in RNAs encoding key jasmonate signalling regulators. From among 34 screened membrane protein mutant lines, mutations in several clade 3 GLUTAMATE RECEPTOR-LIKE genes (GLRs 3.2, 3.3 and 3.6) attenuated wound-induced surface potential changes. Jasmonate-response gene expression in leaves distal to wounds was reduced in a glr3.3 glr3.6 double mutant. This work provides a genetic basis for investigating mechanisms of long-distance wound signalling in plants and indicates that plant genes related to those important for synaptic activity in animals function in organ-to-organ wound signalling.

Unlike plants, animals rely on rapid nervous systems to escape predation. A stationary fly that perceives danger takes less than 300 ms to take off, and this process requires complex whole-body coordination1. Nevertheless, this escape response is too slow if the fly lands on a Venus flytrap, a plant in which electrical signals initiate rapid trap closure2. Whereas fast movements associated with insect capture are exceptional, slower herbivore-induced defence gene expression is widespread in plants and is coordinated between organs3. What, then, is the nature of the long distance signal(s) that leads to defence responses throughout much of a plant body after wounding? Among the many scenarios proposed to explain the nature of systemic wound signals in plants4 is a role for electrical signalling5. However, this has not been substantiated and it is essential to identify genes that underlie this phenomenon.

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Invasiva arter

Inlägg av Tryggve » ons 27 nov 2013, 22:04

En artikel om problemen med invasiva arter i Kina. Det kostar tydligen motsvarande 15 miljarder USD per år i skador på bland annat jordbruk och skogsbruk.

China battles army of invaders
China battles army of invaders

Raft of control measures slows the march of alien species.

When China kicked open the doors to international trade in the late 1970s, not everything that came in was welcome. Along with Western goods and new technologies, alien organisms infiltrated the country. A comprehensive survey now reveals that almost 550 non-native species, from viruses to fish and mammals, have become invasive in the country (see ‘Space invaders’). They are costing an estimated US$15 billion in losses each year, with damage to crops and forests a particular problem.

“As the volume of international trade has grown exponentially, so has the number of alien species,” said Li Bo, director of the Office for Management of Alien Species in the Ministry of Agriculture, Beijing, at the second International Congress on Biological Invasions in Qingdao last month.

Since 2000, China has tightened its regulations on importing plant materials and has enforced strict quarantine requirements. It has also spent more than $1 billion establishing databases of invasive species, monitoring their spread, researching invasive mechanisms and ecological impact, and developing control technologies. This has led to an “explosion of research”, says Wan Fanghao, an ecologist at the Chinese Academy of Agricultural Sciences’ Institute of Plant Protection in Beijing.

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Re: Nature News

Inlägg av Tryggve » ons 27 nov 2013, 22:10

Det kan nog bli en rätt häftig diskussion kring detta, misstänker jag. Arbetet är fortfarande i ett mycket tidigt stadie (vilket påpekas i artikeln), och sedan så är det ju rätt lurigt det här med analyser av storskalig genexpression. Skillnader kan vara lätta att hitta, men att sedan koppa dem och gå vidare....

Immunology: The pursuit of happiness
Immunology: The pursuit of happiness

Researchers have struggled to identify how certain states of mind influence physical health. One biologist thinks he has an answer.

When Steve Cole was a postdoc, he had an unusual hobby: matching art buyers with artists that they might like. The task made looking at art, something he had always loved, even more enjoyable. “There was an extra layer of purpose. I loved the ability to help artists I thought were great to find an appreciative audience,” he says.

At the time, it was nothing more than a quirky sideline. But his latest findings have caused Cole — now a professor at the Cousins Center for Psychoneuroimmunology at the University of California, Los Angeles — to wonder whether the exhilaration and sense of purpose that he felt during that period might have done more than help him to find homes for unloved pieces of art. It might have benefited his immune system too.

At one time, most self-respecting molecular biologists would have scoffed at the idea. Today, evidence from many studies suggests that mental states such as stress can influence health. Still, it has proved difficult to explain how this happens at the molecular level — how subjective moods connect with the vastly complex physiology of the nervous and immune systems. The field that searches for these explanations, known as psychoneuroimmunology (PNI), is often criticized as lacking rigour. Cole's stated aim is to fix that, and his tool of choice is genome-wide transcriptional analysis: looking at broad patterns of gene expression in cells. “My job is to be a hard-core tracker,” he says. “How do these mental states get out into the rest of the body?”

With his colleagues, Cole has published a string of studies suggesting that negative mental states such as stress and loneliness guide immune responses by driving broad programs of gene expression, shaping our ability to fight disease. If he is right, the way people see the world could affect everything from their risk of chronic illnesses such as diabetes and heart disease to the progression of conditions such as HIV and cancer. Now Cole has switched tack, moving from negative moods into the even more murky territory of happiness. It is a risky strategy; his work has already been criticized as wishful thinking and moralizing. But the pay-off is nothing less than finding a healthier way to live.

“If you talk to any high-quality neurobiologist or immunologist about PNI, it will invariably generate a little snicker,” says Stephen Smale, an immunologist at the University of California, Los Angeles, who is not affiliated with the Cousins Center. “But this doesn't mean the topic should be ignored forever. Someday we need to confront it and try to understand how the immune system and nervous system interact.”

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Artikel tillbakadragen.

Inlägg av Tryggve » ons 04 dec 2013, 12:47

Det här är en viktig nyhet, värd att nämna. Inte för att kritiker påverkas av det. Att tidskrifter drar tillbaka en artikel mot författarens önskan är (vad jag har förstått) rätt ovanligt.

Study linking GM maize to rat tumours is retracted
Study linking GM maize to rat tumours is retracted

Publisher withdraws paper despite authors' objections, citing weak evidence.

Bowing to scientists' near-universal scorn, the journal Food and Chemical Toxicology today fulfilled its threat to retract a controversial paper claiming that a genetically modified (GM) maize causes serious disease in rats, after the authors refused to withdraw it.

The paper, from a research group led by Gilles-Eric Séralini, a molecular biologist at the University of Caen, France, and published in 20121, showed “no evidence of fraud or intentional misrepresentation of the data”, said a statement from Elsevier, which publishes the journal. But the small number and type of animals used in the study mean that “no definitive conclusions can be reached”. The known high incidence of tumours in the Sprague–Dawley strain of rat ”cannot be excluded as the cause of the higher mortality and incidence observed in the treated groups”, it added.

Today’s move came as no surprise. Earlier this month, the journal’s editor-in-chief Wallace Hayes threatened retraction if Séralini refused to withdraw the paper. Elsevier retracted the paper shortly after a press conference in Brussels this morning, in which Séralini protested his innocence. He and his team stand by their results, and allege that the retraction derives from the journal's editorial appointment of biologist Richard Goodman, who previously worked for biotechnology giant Monsanto for seven years.
EDIT: förlagets kommentarer här: http://www.elsevier.com/about/press-rel ... toxicology

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Annan artikel

Inlägg av Tryggve » tor 05 dec 2013, 21:48

Men anledning av tillbakadragandet (är det en bra svensk term att använda här, förresten) av GMO-artikeln, här är ett exempel från Retraction Watch angående en författare som i ett antal år har försökt att dra tillbaka en av sina publikationer från Nature, men inte fått gehör. Rätt anmärkningsvärt på sätt och vis.

A 2005 Nature study that has vexed one of its authors since 2007 is finally being retracted.
A 2005 Nature study that has vexed one of its authors since 2007 is finally being retracted.

The notice for “Dance reveals symmetry especially in young men,” by William M. Brown, Lee Cronk, Keith Grochow, Amy Jacobson, C. Karen Liu, Zoran Popovic´& Robert Trivers, says very little:
EDIT: ja, det är inte huvudförfattaren som har försökt att få artikel tillbakadragen, ska sägs. Personen stod som sista namn. Men här var det fråga om fusk, något som tydligen hade påpekats redan fyra år innan artikeln drogs tillbaka.

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Re: Nature News

Inlägg av Tryggve » fre 06 dec 2013, 12:17

Detta var mer kuriosa, men ändå lite roligt. En del jagar rätt på tidig utrustning från genomikens början, för att de ska kunna bevaras på museer och liknande.

Museums hunt for relics from genomics’ early days

Museums hunt for relics from genomics’ early days


Collectors band together to salvage cast-off equipment.

In a former envelope factory sits a boxy grey and blue machine the size of an oven — the tenth acquisition this year for a Massachusetts science museum. It is a colony picker, a robotic arm that plucks bacteria from Petri dishes and drops them into a tray with 96 wells, from which DNA is extracted, amplified and sequenced.

At the start of this century, the device powered genomics research at the Whitehead Institute for Biomedical Research in Cambridge, Massachusetts. Now retired, it rests in the warehouse of the Massachusetts Institute of Technology (MIT) Museum, sandwiched between a sewing machine from around the 1920s and an analog computer from the 1950s.

Genomics researchers might find it hard to believe that museum patrons would be interested in paying homage to a piece of lab equipment as pedestrian as a colony picker. Curators of science and technology museums say that is exactly the problem.

“Very few scientists have any idea that they should preserve these things,” says Thomas Söderqvist, director of the Medical Museion in Copenhagen. “They just throw them out.”

But in the past two years, a confederation of about a dozen science museums has co­alesced around the need to preserve relics of the genomics revolution, in an effort known as the Museum Genomics Initiative. It was born of a concern that, in a time of shrinking museum budgets, the collection of scientific artefacts was not keeping pace with innovation. This shortcoming has been felt across disciplines, says Simon Chaplin, head of the Wellcome Collection’s library of biomedical history in London, which has also joined the initiative. But he says that an effort focused on genomics makes sense because of the field’s importance for medicine, appeal to the public and rapid growth since the late 1990s. “There’s a real risk that if we don’t act quickly, the material legacy of genomics will be lost,” he says.

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Re: Nature News

Inlägg av nanowire » fre 06 dec 2013, 12:29

Tack Tryggve för att du tar dig tid att highlighta highlightsen :)
"nanowire - Keeping beliefs consistent with the laws of nature since '74"

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Re: Nature News

Inlägg av Blafsen » fre 06 dec 2013, 12:54

nanowire skrev:Tack Tryggve för att du tar dig tid att highlighta highlightsen :)
Håller med. Att det inte blir så mycket respons på inläggen beror inte på att de är ointressanta, utan för att det är mer intressant läsning än diskussionsunderlag.

Åtminstone för oss dödliga.
......men jag är inte smartare än en femteklassare.

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Re: Nature News

Inlägg av Tryggve » fre 06 dec 2013, 13:46

Tackar, kul med uppskattning.
Jag inser att det kanske inte är det bästa materialet för diskussionsunderlag alla gånger, där håller jag med.

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Jadekaninen

Inlägg av Tryggve » tis 17 dec 2013, 13:53

Fysik/astronomi är ju inte mitt område direkt, men när Nature skriver om den första framgångsrika månlandningen sedan 1976 så är det väl värt ett inlägg i den här tråden.

China lands rover on Moon
China lands rover on Moon

Spacecraft touches down successfully, but not where expected

At 9.11 on Saturday night, the Chang’e 3 spacecraft hovered just metres above the Moon. Seconds later, it shut off its engines and dropped to the surface. With that plunge, China became only the third country to land a craft on the Moon, and the first to do so since the Soviet Union in 1976.

It was the end of a tense 11 minutes. Engineers at the Beijing Aerospace Control Center started landing operations with Chang’e 3 some 15 kilometres above its target, and the touchdown depended on an entirely domestically designed and manufactured engine. They needn’t have worried — the machine, the most powerful China has ever put on a spacecraft, automatically adjusted its power, between 1,500 and 7,500 newtons, to balance the gravitational pull and smooth the lander’s approach.

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Re: Jadekaninen

Inlägg av Hexmaster » ons 18 dec 2013, 08:31

Spacecraft touches down successfully, but not where expected
[...]
China had originally publicized a landing location in Sinus Iridum (Bay of Rainbows) — a level plain thoroughly surveyed by a previous Chinese mission. Some media even stated that Chang’e 3 landed there. But it has since been confirmed that the spacecraft landed slightly to the east of the area, in the northern part of Mare Imbrium (Sea of Rains).
:-)

retractionwatch.com är förresten en finfin sida att hålla koll på.
Detta skall jag visa dig medelst ett stort papper som jag har fyllt med faktiska upplysningar! - Strindberg

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Re: Nature News

Inlägg av Blafsen » ons 18 dec 2013, 11:21

Med tanke på att Indien har skickat iväg en sond mot Mars, funderar man ju på om vi har en ny rymdkapplöpning på gång mellan Asiens giganter? Frågan är ju också då om USA och Ryssland hakar på i kampen om rymdherraväldet, eller om de lämnar över denna dyra tävling till "uppkomlingarna"?

Eller går utvecklingen mot mer samarbete mellan rymdnationerna även i Asien?
......men jag är inte smartare än en femteklassare.

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Re: Jadekaninen

Inlägg av Tryggve » ons 18 dec 2013, 13:24

Hexmaster skrev: :-)

retractionwatch.com är förresten en finfin sida att hålla koll på.
Tror t o m att jag startade en tråd om den sidan för ett tag sedan, nu när jag tänker efter.

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Re: Jadekaninen

Inlägg av pwm » ons 18 dec 2013, 13:41

Tryggve skrev:
Hexmaster skrev: :-)

retractionwatch.com är förresten en finfin sida att hålla koll på.
Tror t o m att jag startade en tråd om den sidan för ett tag sedan, nu när jag tänker efter.
http://forum.vof.se/viewtopic.php?f=10&t=17883

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