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SUBIECT: Geron - test clinic cu celule stem embrionare, SUA

Geron - test clinic cu celule stem embrionare, SUA acum 7 ani 10 luni #4428

Am citit azi cateva lucruri despre Geron (www.geron.com). Stiu ca s-a postat si in alta parte despre subiect, dar am zis sa fac un thread nou ..sa adunam aici informatiile, si evenimentele ce vor urma privind acest "clinical trial".

Uite ce am gasit eu:

http://www.fabricadebani.ro/news.aspx?iid=16022&sid=103
<strong>SUA incepe teste cu celule stem embrionare</strong>

23 ianuarie 2009

Autoritatile de reglementare din SUA au aprobat prima utilizare de celule stem provenite dintr-un embrion pentru tratamentul uman. La numai doua zile dupa investirea presedintelui Barack Obama, care se opunea interdictiei instituite de George Bush pentru acordarea de finantare federala pentru cercetarile in domeniul celulelor stem provenite din embrion, Administratia pentru Produse alimentare si medicamente din SUA a aprobat solicitarea companiei americane din domeniul biotehnologiilor Geron sa inceapa teste clinice pentru pacienti care sufera de afectiuni severe ale maduvei spinarii.

Cercetatorii din institutii academice sau private au inceput sa foloseasca la tratamentul pacientilor celule stem provenite din organisme adulte. Geron, o companie cu sediul in Menlo Park, California, avanseaza rapid pe directia utilizarii celulelor stem embrionare, despre care cercetatorii cred ca au un potential mult mai mare pentru ca pot evolua pentru a se transforma in oricare din tipurile de celule dintr-un organism, transmite Financial Times.

Decizia agentiei federale permite companiei Geron sa inceapa testele clinice pentru a verifica produsul denumit deocamdata GRNOPC1, dupa care va cere aprobari pentru potentiala comercializare – proces care poate dura pana la 3 ani. Presedintele companiei, Thomas Okarma, citat de FT, a declarat ca nu crede ca a existat vreo interferenta politica in termenul obtinerii aprobarii pentru testare, dar si-a declarat nemultumirea ca interdictia impusa de George Bush a pus intreaga greutate a costurilor cercetarilor asupra celulelor stem pe umerii firmelor.

Comunicatul firmei anunta ca agentia americana a medicamentelor, FDA, si-a dat acordul pentru un test din faza I numit GRNOPC1. Un test din faza I implica un numar mic de pacienti pentru a se vedea buna tolerare de catre om a unei terapii inovatoare, anunta Yahoo Actualite.

Obiectivul testului GRNOPC1 este de a injecta unor voluntari paralizati celule derivate din celule embrionare umane, in speranta ca ele pot regenera celulele nervoase afectate si, potential, sa permita persoanei paralizate sa-si regaseasca sensibilitatea si capacitatea de miscare.

Utilizarea celulelor stem embrionare ridica o problema de etica, deoarece sunt prelevate de la embrioni in primul stadiu de dezvoltare (blastocite) si embrionul este distrus.

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http://www.monitorulexpres.ro/?mod=monitorulexpres&p=S%C4%83n%C4%83tate&a=citeste&s_id=71033
Stetoscop
27.01.2009 08:51:38 (Arhiva)

<strong>Americanii dau liber la tratamente cu celule stem</strong>

Compania americană specializată în biotehnologie Geron Corporation a anunţat că a obţinut autorizaţia de începere a primelor teste pe oameni vizînd terapia ce foloseşte celule-suşă embrionare. Aceste teste vor fi efectuate asupra unor pacienţi rămaşi paralizaţi în urma leziunilor suferite la nivelul măduvei spinării. Firma californiană a precizat într-un comunicat că Food and Drug Administration (FDA), administraţia care se ocupă de reglementarea medicamentelor şi alimentelor în Statele Unite, şi-a dat acordul pentru începerea primei faze de testare, numită GRNOPC1. Celulele-suşă reprezintă o sursă de celule şi ţesuturi noi. Celulele-suşă înlocuiesc celulele din organism în momentul în care acestea mor. Celulele-suşă embrionare au cel mai mare potenţial, pentru că ele se pot dezvolta în orice tip de ţesut şi celule din organism. Utilizarea lor ridică, totuşi, probleme de natură etică, pentru că embrionii sînt distruşi în timpul procesului de prelevare a celulelor-suşă. Specialiştii mai atrag atenţia că tratamentul este eficient doar în cazul persoanelor paralizate în urmă cu cel mult două săptămîni înaintea începerii terapiei. „Lucrul acesta marchează începutul unui nou capitol în tratamentele terapeutice: restabilirea funcţiei organelor şi a tesuturilor prin injectarea unor celule sănătoase. Scopul final este de a restabili funcţiile măduvei spinării", a declarat dr. Thomas Okarma, director executiv al Geron Corporation şi iniţiatorul proiectului.

Cremă contra herpesului

Cercetătorii americani susţin că au creat o cremă care poate preveni infectarea cu herpes genital. Virusul este purtat de milioane de oameni din întreaga lume şi, deşi boala poate fi controlată, răspîndirea virusului prin sex este greu de stopat. Se crede că această cremă, care pînă în prezent a fost testată doar pe şoareci de laborator, opreşte transmiterea virusului. „Una dintre proprietăţile atractive ale acestei creme este că oferă protecţie împotriva virusului, chiar dacă este aplicată cu o săptămînă înainte de contactul sexual. Dacă vom obţine aceleaşi rezultate şi la oameni, această descoperire va avea un impact puternic în prevenirea transmiterii virusului“ a spus prof. Judy Lieberman, autorul studiului.
de: M. Ex.

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Akuma in functie de ziar, stirea asta va fi modificata in fel si chip. A noastre ziare nu fac exceptie.

Sursele cele mai pertinente sunt de pe forumul lui Adi:

Threadul cu ultimele discutii despre Geron:
http://sci.rutgers.edu/forum/showthread.php?t=113884

Un articol de pe blogul lui Wise despre Geron il bag si aici in engleza, in caz ca se schimba linkul:
http://wiseyoung.wordpress.com/2009/01/27/geron/

Geron’s Oligodendroglial Precursor Cell Therapy Trial
By Wise Young

Geron’s Oligodendroglial Precursor Cell Therapy Trial
by Wise Young, PhD MD.
W. M. Keck Center for Collaborative Neuroscience
Rutgers University, 604 Allison Road, Piscataway, NJ 08854-8082
Posted 26 January 2009, updated 29 January 2009

On January 21, 2009, Geron announced that they received the approval of the U.S. Food and Drug Administration (FDA) to do the first clinical trial that will evaluate the safety of cells derived from human embryonic stem cells (HESC). The trial will transplant oligodendroglial precursor cells (OPC’s) derived from an early HESC line isolated in 1997 by Jamie Thomson and colleagues in Wisconsin.

This is a landmark trial not only because it is the first trial of an HESC-derived cell but because it is the first such trial for spinal cord injury. HESC’s are derived from blastocysts, the first stage of development after fertilization. Geron had funded the work of Jamie Thomson in the late 1990’s. President George W. Bush banned federal funding of research on HESC derived after August 2001.

In 1999, John McDonald and his colleagues [1] transplanted predifferentiated mouse embryonic stem cell into contused spinal cords of rats, comparing them against fibroblasts expressing neurotrophins. At 2-5 weeks, the transplanted cells had differentiated into astrocytes, oligodendroglia, and neurons, migrating as far as 8 mm from the injury site. Gait analysis showed that the transplanted rats showed better hindlimb weight support and partial hindlimb coordination.

In 2005, Faulkner & Keirstead derived [2] oligodendroglial progenitor cells (OPC) from human embryonic stem cells. OPC’s transplanted into rat spinal cord at 7 days after contusion enhanced remyelination and improved locomotor recovery [3]. In other studies, Keirstead, et al. showed that contused rat spinal cords undergo progressive demyelination [5], OPC implants were not harmful in rats [6], transplanted OPC cells replaced oligodendroglia [7], and myelin loss is greater in contusion injury [8] and older animals [9].

Armed with this data, Geron proposed to carry out a phase 1 clinical trial to evaluate the safety of transplanting OPC derived from human embryonic stem cells (HESC) on people with subacute spinal cord injury. This would be the first time any cell from a known and well-characterized human embryonic stem cell line would be used to treat any condition. It was also the first proposal to use HESC-derived cells to treat human spinal cord.

Geron did extensive studies of the safety and mechanisms of OPC effects on spinal cord injury. In 2006, Zhang, et al. [10] reported that the HESC-derived OPC secrete neurotrophic factors, suggesting an alternative mechanism for the beneficial effects of the cells on recovery after contusion injury. In 2007, Okamura, et al. [11] reported that the HESC-derived OPC cells do not stimulate strong immune responses in vitro, providing the rationale for using non-HLA matched heterologous cells.

From 2005 on, Geron repeatedly announced their intentions to transplant the HESC-derived OPC cells into people with spinal cord injury but the FDA did not approve the clinical trial [12]. It became clear that FDA approval of the first HESC-derived cell transplant faced significant scientific [13] and bioethical hurdles [14]. In May 2008, the FDA placed a hold on the Geron’s application [15] but Geron said that they were addressing the concerns and were confident of approval [16].

On January 21, 2009, Geron announced that the FDA approved the application for the [17]. The media response was massive [18]. The story was carried by almost every news source [18-20]. The community response was initially strongly positive. Coming on the 3rd day after President Barack Obama’s inauguration, some thought that the approval of the first HESC trial was due to Obama’s coming to power.

The exuberance faded as people read the fine print. First, the trial is not for people with chronic spinal cord injury. It is intended to be used within 2 weeks after injury for people with complete thoracic spinal cord injury. Second, the goal of the trial is to show safety and feasibility, not necessarily efficacy. Third, the cells have been differentiated to the point that they are no longer acting as stem cells but only as oligodendroglia.

The trial focuses on subacute spinal cord injury in part because animal data suggest that the cells alone would be effective only when transplanted into rats within two weeks after injury. This does not necessarily mean that the cells would not be effective in chronic human spinal cord injury, especially when combined with some other therapy (such as chondroitinase, Cethrin, or Nogo-A antibody).

The trial is designed to establish safety of the cells. One worry of the FDA and the scientific community is that HESC will produce teratomas (a stem cell tumor). Geron played it very safe. They differentiated these cells so that they produce only oligodendroglial cells and are very unlikely to produce teratomas. They chose to transplant the cells into patients with thoracic complete spinal cord injuries so that if the cells turned into tumors, the neurological consequences will be minimized.

According to the New York Times by Andrew Pollack [21], Thomas B. Okarma, Geron’s chief executive, did not think that the Bush Administration’s objections to embryonic stem cells delayed approval. “We really have no evidence, ” Dr. Okarma said, “that there was any political overhang.” But Robert Klein, chairman of California Institute of Regenerative Medicine thought that Bush had pressured the FDA.

Some scientists were critical of the trial. For example, according to the Pollack article, John A. Kessler, who is chair of Neurology and director of the Stem Cell Institute at Northwestern University and father of a spinal-injured daughter, said that a treatment might not apply to more seriously injured people. “We really want the best trial to be done for this first trial, and this might not be it,” he said.

Kessler was referring to the use of myelinating cells to treat people with so-called “complete” spinal cord injury. People with such severe injuries should have fewer axons crossing the injury site to myelinate. Okarma responded that this trial was designed to establish the safety of the treatment and lack of efficacy in this trial was not a problem.

The same article cited Steven Goldman, chair of neurology at the University of Rochester, “It’s not ready for prime time, at least in my mind, until we can be assured that the transplanted cells have completely lost the capacity for tumorogenicity.” Okarma pointed out that Geron has done numerous studies to show that the cells do not contain any residual embryonic stem cells and did not form tumors when transplanted into animals, even after a year.

Geron’s application for the clinical trial was over 22,000 pages long and the preparatory work cost $45 million. While Okarma said that he did not think that the Bush Administration impeded the application for this particular trial, he did think that the Federal government slowed the progress in the field by making it difficult for researchers to do embryonic stem cell research. Clearly, given the $45 million and 4 years required for the approval of the clinical trial, it was not an easy process.

Geron’s web site and news reports indicate that the trial will treat 8-10 patients who are within 2 weeks after “complete” thoracic spinal cord injury. It will probably start in July 2009. However, many details are unclear. Before the FDA placed a hold on the trial application in May 2008, Geron had said that the cells would be transplanted into the spinal cord of patients undergoing spinal cord decompressive surgery and all the patients will receive a 2-month period of pharmacological immunosuppression . It is not clear that the same regimen will be used.

In the meantime, the reaction of the spinal cord injury community has ranged from exuberance over the approval of the first HESC trial [22] to deep pessimism over comments by Okarma, who said that people with “complete” spinal cord injury have no chance of recovering any function, or something to this effect. Many people in the spinal cord injury community [23] were disappointed at being excluded from the study which is only for the newly injured.

As John Smith commented in CareCure [25]:

Tom Okarma is cool, groovy, dope or whatever other adjective you might use to convey a leader with media savvy. Our 21st century world is so ravenous to scoop one another there is little respect for the truth and process.

I’ve met the man. I’ve spoken to him privately twice and questioned him about Geron’s commitment to SCI and the meaning of this trial for chronics. This trial is of staggering importance for Geron and those of us living the life. However, it is not momentous for us in the sense of being a cure-all.

There is no way Okarma is going to speculate beyond the scope of this trial’s goals. That would be a terrible error in judgment and one to which he is immune. He is a doctor and a scientist, not a snake oil salesman. He is also the CEO of Geron. Their reputation is on the line with this trial. I admire him for the self-control necessary to put a brake on the message.

I asked him point blank, one on one, away from the glare of cameras and the notepads of journalists what this trial meant for chronics. He repeated what was quoted in the various articles reporting on the FDA approval. Evidence exists that this therapy will not work for chronics due to scarring.

My son is six years post injury. Naturally, his answer was disappointing. But, of course, that is not the end of the story, though it is likely that is all Okarma will dare to say on the subject.

He knows all about efforts to deal with the scar tissue that range from bridging the injury site to dissolving the scar to the work headed by Keirstead at UCI (post #13). Nonetheless, he’s not going to comment on that or leapfrog the purpose of the current trial. He is going to stay on point. Bless him for that; now is not the time to get sidetracked from the journey ahead.

As this trial proceeds through its various stages, the world of SCI research is going to be turned upside down. In part, it will be due to the incredible science funded by Geron. It will also be because of the confluence of research supported by the soon to be minted CDRPA, Stem Cell Research Enhancement Act, The CIRM and ongoing studies conducted by the likes of Dr. Davies, Dr. Keirstead, Dr. Kerr, the China-SCI Network and others.

I’m 62, and I plan on seeing my son walk again. I accept that curing SCI is a process. So, hold on, it’s going to be quite a ride.

Others thought that the Geron trial is opening doors for other companies and other trials. ChipS [26] pointed out:

I think all the pessimists are missing the big picture here. First off, this is a huge hurdle that has been overcome. The political tide is changing, and to have this trial announced on the heals of this transition will establish a new era of support for this type of work.

Next, this study involves only the limited lines of hESC that was developed prior to the 2001 ban. Given the promised policy change that will likely overturn that ban on fed funding for new lines, this could increase the possibilities of the effectiveness for more treatments in the very near future.

Now that this news has been plastered all over the internet and TV news, the public has been reminded that there are many people suffering from paralysis who are hoping for this trial to be a success. Publicity is an ally. We need to do our part to exploit this opportunity. Write letters to congress, local papers, ect…

Lastly, now that Geron has been given the green light and popped the FDA’s cherry on these types of trials, many more start-ups will be able to come to join the party. Suddenly, all is possible again. Geron took a huge gamble here. The fate of the company is riding on this. I am praying this is a success. This had to happen here. I suspect that other nations will soon follow suit as many labs will be collaborating internationally and sharing information in an attempt of cracking the next walnut, and gaining a foothold in this new and promising market.

Good things are coming folks. It may not be as soon as we want, but the flood gates are cracked and are opening more and more.

In summary, the first clinical trial of cells derived from human embryonic stem cells has been approved by the U.S. FDA and will soon start. It is not the trial that many hoped to see, i.e. a trial that will show that human embryonic stem cells cure spinal cord injury. Rather, it is a small trial to assess the safety and efficacy of transplanting oligodendroglial precursor cells derived from one of the first human embryonic stem cell lines isolated in 1997. The trial will test the cells in patients that are within 2 weeks after severe spinal cord injury. Its most likely outcome is to show that these cells can be safely transplanted to the spinal cord. If this trial is successful, it will lead to other trials. This is the first and an important step.

References

1. McDonald JW, Liu XZ, Qu Y, Liu S, Mickey SK, Turetsky D, Gottlieb DI and Choi DW (1999). Transplanted embryonic stem cells survive, differentiate and promote recovery in injured rat spinal cord. Nat Med 5: 1410-2. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=10581084

2. Faulkner J and Keirstead HS (2005). Human embryonic stem cell-derived oligodendrocyte progenitors for the treatment of spinal cord injury. Transpl Immunol 15: 131-42. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=16412957

3. Keirstead HS, Nistor G, Bernal G, Totoiu M, Cloutier F, Sharp K and Steward O (2005). Human embryonic stem cell-derived oligodendrocyte progenitor cell transplants remyelinate and restore locomotion after spinal cord injury. J Neurosci 25: 4694-705. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15888645

4. Nistor GI, Totoiu MO, Haque N, Carpenter MK and Keirstead HS (2005). Human embryonic stem cells differentiate into oligodendrocytes in high purity and myelinate after spinal cord transplantation. Glia 49: 385-96. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15538751

5. Totoiu MO and Keirstead HS (2005). Spinal cord injury is accompanied by chronic progressive demyelination. J Comp Neurol 486: 373-83. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15846782

6. Cloutier F, Siegenthaler MM, Nistor G and Keirstead HS (2006). Transplantation of human embryonic stem cell-derived oligodendrocyte progenitors into rat spinal cord injuries does not cause harm. Regen Med 1: 469-79. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17465839

7. Yang H, Lu P, McKay HM, Bernot T, Keirstead H, Steward O, Gage FH, Edgerton VR and Tuszynski MH (2006). Endogenous neurogenesis replaces oligodendrocytes and astrocytes after primate spinal cord injury. J Neurosci 26: 2157-66. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=16495442

8. Siegenthaler MM, Tu MK and Keirstead HS (2007). The extent of myelin pathology differs following contusion and transection spinal cord injury. J Neurotrauma 24: 1631-46. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17970626

9. Siegenthaler MM, Ammon DL and Keirstead HS (2008). Myelin pathogenesis and functional deficits following SCI are age-associated. Exp Neurol 213: 363-71. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=18644369

10. Zhang YW, Denham J and Thies RS (2006). Oligodendrocyte progenitor cells derived from human embryonic stem cells express neurotrophic factors. Stem Cells Dev 15: 943-52. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17253955

11. Okamura RM, Lebkowski J, Au M, Priest CA, Denham J and Majumdar AS (2007). Immunological properties of human embryonic stem cell-derived oligodendrocyte progenitor cells. J Neuroimmunol 192: 134-44. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17996308

12. Keim B (2007). The Company Who Cried Clinical Trial: Geron’s Unfulfilled Stem Cell Promises. blog.wired.com. http://blog.wired.com/wiredscience/2007/07/the-company-who.html

13. Puceat M and Ballis A (2007). Embryonic stem cells: from bench to bedside. Clin Pharmacol Ther 82: 337-9. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17637781

14. Hviid Nielsen T (2008). What happened to the stem cells? J Med Ethics 34: 852-7. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=19043108

15. Anonymous (2008). FDA’s delay of Geron ESC trial raises concerns. {May 15, 2008. http://www.fiercebiotech.com/story/fda-s-delay-of-geron-esc-trial-raises-concerns/2008-05-15?utm_medium=rss&utm_source=rss&cmp-id=OTC-RSS-FB0

16. Smith A (2008). Human stem cell tests could be near. CNNMoney.com. http://money.cnn.com/2008/02/11/news/companies/geron/index.htm?postversion=2008021212

17. Anonymous (2009). Geron Receives FDA Clearance to Begin World’s First Human Clinical Trial of Embryonic Stem Cell-Based Therapy. Geron. http://www.geron.com/media/pressview.aspx?id=863

18. Anonymous (2009). Geron Corp. (GERN) Gains FDA Clearance to Begin World’s First Human Clinical Trial of Embryonic Stem Cell-Based Therapy. http://blogs.finditt.com/QualityStocks/Post.aspx?postID=32925

19. Coghlan A (2009). Historic trial to treat spinal injury with stem cells New Scientist http://www.newscientist.com/article/dn16475-historic-trial-to-treat-spinal-injury-with-stem-cells.html

20. Madrigal A (2009). FDA OKs First Human Trials of Embryonic Stem Cells Wired. January 23, 2009. http://blog.wired.com/wiredscience/2009/01/fda-approves-em.html

21. Pollack A (2009). F.D.A. Approves a Stem Cell Trial. New York Times. January 23, 2009. http://www.nytimes.com/2009/01/23/business/23stem.html?_r=1

22. Childs D and Bhatt J (2009). New Prez, New Studies: New Era for Stem Cells. {Jan. 26, 2009. http://abcnews.go.com/Health/President44/story?id=6727016&page=1

23. Carecure (2009). Geron. http://sci.rutgers.edu/. 27 January 2009. http://sci.rutgers.edu/forum/showthread.php?t=113884

24. Smith J (2009). Geron. Care Cure Community. 27 January 2009. http://sci.rutgers.edu/forum/showpost.php?p=990125&postcount=20

25. ChipS (2009). Geron. Care Cure Community. 27 December 2009. http://sci.rutgers.edu/forum/showpost.php?p=990160&postcount=21

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Articolul lui Wise ar fi interesant de tradus. As spune eu pe scurt ce am inteles din el...dar nu vreau sa ma grabesc si sa zic vreo prostie.
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Ultima editare: acum 6 ani 8 luni by daniel.
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Re:Geron - test clinic cu celule stem embrionare, SUA acum 7 ani 10 luni #4451

E un studiu ptr.leziuni recente nu cronice .10-15 zile de la accident.
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never give up hope
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Re:Geron - test clinic cu celule stem embrionare, SUA acum 7 ani 10 luni #4461

Super tare ... mai putin si ne pune pe picioare ;)
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Re:Geron - test clinic cu celule stem embrionare, SUA acum 7 ani 9 luni #4762

Obama dă liber cercetării în domeniul celulelor suşă

Barack Obama va ridica interdicţia impusă în urmă cu opt ani asupra cercetării în domeniul celulelor suşă embrionare de predecesorul său, George W. Bush.

Informaţia a fost furnizată de consilierul preşedintelui Obama, David Axelrod, în cadrul unei emisiuni difuzate de Fox News.

În 2001, Bush a limitat fondurile federale destinate cercetărilor asupra liniilor de celule suşă embrionare care erau deja colectate. Măsura a fost interpretată ca un gest de a obţine simpatia susţinătorilor săi conservatori, creştini, care considerau cercetările asupra celulelor suşă ca o formă de distrugere a unor potenţiale vieţi (pentru că celulele sunt extrase din embrioni umani).

Celulele suşă embrionare sunt celule de bază care se pot dezvolta în organism în orice tip de celulă sau ţesut.

Cercetătorii consideră că studiile în acest domeniu ar putea sta la baza unor formule de tratament pentru afecţiuni cronice, grave, precum diabetul, Parkinson şi maladiile cardiace.

Preşedintele Barack Obama s-a angajat să ridice interdicţia impusă de Bush şi chiar să susţină cercetările în acest domeniu, în timpul campaniei sale electorale. În cadrul discursului de inaugurare, preşedintele SUA a promis să redea ştiinţei şi cercetării rolul cuvenit.

Departamentul pentru reglementarea medicamentelor şi alimentelor (Food and Drug Administration) din Statele Unite a anunţat că în curând se vor face primele teste în cadrul cărora se va încerca tratarea pacienţilor cu afecţiuni ale coloanei vertebrale. Celulele suşă vor fi folosite pentru a regenera nervii spinali.

:blink:
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Re:Geron - test clinic cu celule stem embrionare, SUA acum 7 ani 8 luni #5072

Barack Obama va finanţa din nou celulele stem

Fostul preşedinte al Statelor Unite George W. Bush a blocat fondurile guvernamentale pentru direcţiile de cercetare privind celulele stem embrionare create după 9 august 2001, scrie BBC News . Obama va înlătura însă această restricţie, mişcare anunţată şi în cadrul programului său electoral din toamnă.



Analiştii americani spun că decizia sa va îmboldi Congresul să renunţe şi la interdicţia de cheltuire a fondurilor provenite din taxe pentru crearea de embrioni. Această interdicţie, botezată “amendamentul Dickey-Wicker”, este în vigoare din 1996 şi a fost înnoită de Congresul american în fiecare an.

Practica făuririi de embrioni este una de rutină în clinicile private, însă amendamentul Dickey-Wicker le-a pus beţe în roate cercetătorilor federali încă dinaintea restricţiilor impuse de Bush, ei fiind obligaţi să folosească numai embrioni rămaşi în urma tratamentelor de fertilitate.

Această schimbare în politica statului american face parte din promisiunea preşedintelui Obama că cercetarea ştiinţifică va fi privată de amestecuri politice în timpul administraţiei sale.

Sursa Mediafax
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Re:Geron - test clinic cu celule stem embrionare acum 7 ani 3 zile #13641

Primele celule susa embrionare umane din "era Obama" au primit unda verde din partea autoritatilor

"Sunt bucuros sa anunt ca incepand de astazi avem noi linii de celule susa embrionare umane ce sunt disponibile pentru comunitatea cercetatorilor, in cadrul noii politici oficiale referitoare la folosirea acestor celule", a declarat medicul Francis Collins, directorul National Institutes of Health (NIH).

celule_stem_pluripotente.jpg


"Potrivit reglementarilor, aceste celule susa sunt derivate din embrioni obtinuti in urma unui proces etic aprobat", a adaugat Francis Collins, precizand totodata faptul ca NIH se pregateste sa puna mai multe astfel de celule la dispozitie cercetatorilor din serviciile medicale federale.

Presedintele Barack Obama a anuntat, pe 9 martie, ca va reveni asupra interdictiei de efectuare a cercetarilor medicale asupra celulelor susa embrionare umane, impusa de predecesorul sau, George W. Bush, in 2001, din motive morale si religioase, potrivit carora un embrion este o fiinta umana intreaga, ce nu poate fi distrusa in numele stiintei.

Interdictia impusa de administratia Bush viza celulele susa embrionare umane create dupa adoptarea acestei hotarari.

Presedintele Obama a invocat, anuntand aceasta schimbare a politicii oficiale americane, potentialul avut de aceste celule in tratarea a numeroase maladii incurabile, precum diabetul si maladia Parkinson sau regenerarea tesuturilor nervoase din maduva spinarii, distruse in urma unor accidente si care au determinat paralizia pacientilor.

Celule susa sunt celule care au capacitatea de a se transforma in orice tip de celule - cardiace, hepatice sau pulmonare.

Unsprezece din aceste noi linii de celule susa aprobate de NIH au fost realizate de Spitalul pentru copii din Boston, iar celelalte doua de Universitatea Rockefeller din New York.

Potrivit comunicatului NIH, alte 96 de linii de celule susa sunt supuse, in prezent, procedurilor de aprobare impuse de NIH si vor putea fi puse ulterior la dispozitia cercetatorilor din sistemul public de sanatate.

Peste 30 de credite pentru cercetare, in favoarea NIH, totalizand peste 20 de milioane de dolari, au fost aprobate pentru bugetul anului 2009, care au propus folosirea acestor celule susa embrionare umane. Aceste fonduri au fost inghetate pana cand liniile de celule cerute vor fi deblocate.

Potrivit regulilor finale de utilizare a acestor celule susa, stabilite de NIH si intrate in vigoare in luna iulie, finantarea pentru cercetarile medicale din domeniul public vizeaza exclusiv acele celule susa ce provin din embrioni umani supranumerari abandonati de cupluri in clinicile pentru fecundatia in vitro si care ar fi oricum distrusi. Obtinerea de embrioni doar in scopuri stiintifice nu este legala.

Sursa: Mediafax
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Re:Geron - test clinic cu celule stem embrionare acum 6 ani 5 luni #17189

M-am apucat de tradus un al doilea video de la conferinta Bedford Research Foundation, din 2008 http://spinalcordworkshop.org/. E vorba despre prezentarea Doctorului Hans Keirstead.

Hans Keirstead e omul de stiinta din spatele testelor clinice de la Geron.

Eram curios ce s-a intamplat cu aceste teste clinice, caci totusi a trecut un an de atunci.

Se fac unele confuzii in legatura cu acest test clinic si venirea la putere a lui Obama. Cred ca stirile despre Obama ar trebui sa le punem in alt thread.

Hartiile pentru aprobarea testului clinic erau pregatite cu mult inainte de venirea la putere a lui Obama. Si linia de celule pe care lucreaza provine din 1997. Ziarele de la noi, si cele internationale, au o tendinta ne mai intalnita de a amesteca si ameti lucrurile, doar prezentand perspectivele ce li se par lor interesante. Acest lucru e amplificat si de faptul ca de multe ori copiaza unu de la altul si se face din ţânţar armasar, cand se ajunge la capatul celalalt al firului.

Un lucru interesant pe care l-am gasit despre Keirstead e ca lucreaza cu un roman. Multe dintre lucrarile lui de specialitate sunt realizate impreuna cu Gabriel I. Nistor http://www.californiastemcell.com/Gabriel_Nistor__SAB_

Este prima data cand aud despre un cercetator roman lucrand in acest domeniu, dar nu stiu mai multe. Cred ca ar fi interesant sa aflam mai multe.

Deci ce s-a intamplat cu testul clinic pentru care a primit Geron aprobarea?

Acesta este un articol pertinent, aparut recent, 4 iunie 2010:


"A Night with Dr. Hans Keirstead
Prominent Stem Cell Researcher to Speak in Santa Barbara"

Friday, June 4, 2010
By Teisha Rowland


Game-changing discoveries have always been met with resistance. This has been clearly shown by accomplishments achieved by prominent stem cell researcher Dr. Hans Keirstead. Keirstead is an associate professor of Anatomy and Neurobiology and co-director of the Sue and Bill Gross Stem Cell Center at the Reeve-Irvine Research Center at the University of California, Irvine. Keirstead and his lab developed a method using human embryonic stem cells (hESCs) to treat spinal cord injuries and, in 2009, this treatment became the first-ever FDA-approved clinical trial using hESCs.

On June 14, 2010, Keirstead will be giving a presentation at Fess Parker's Doubletree Inn in Santa Barbara on “Stem Cell Research and Its Application for Treatment of Spinal Cord Injury and Disease.”
From Research to Recovery

* Where: Fess Parker's DoubleTree Resort, Reagan Room, 633 E. Cabrillo Blvd., Santa Barbara
* Cost: $25
* Age limit: Not available

Full event details

During his PhD studies at the University of British Columbia in Vancouver, Canadian-born Keirstead developed ground-breaking methods to regenerate damaged spinal cords. To understand how these methods work, it’s important to have an understanding of how the spinal cord normally functions. Two key groups of cells in the spinal cord are neurons, which transmit information, and oligodendrocytes, which act to protect the neurons and ensure that the information travels properly. (The latter are a type of glial cell, so named for being the “glue” of the nervous system). The main way oligodendrocytes carry out their supportive roles is by insulating neurons in a material called myelin—forming a myelin sheath around the neuron’s axon, a long protrusion from the neuron that conducts electrical impulses. This functions similarly to how an electrical wire must be insulated to work properly.

However, when the spinal cord is injured, oligodendrocytes die en masse and consequently the neurons lose their protective myelin sheaths. Even many oligodendrocytes far from the site of impact can die, increasing the area of the spinal cord that has neurons without myelin sheaths. The absence of the myelin sheaths so greatly disrupts the flow of information across the neurons in the spinal cord that paralysis can result even when the neurons themselves are spared.

Consequently, the main approach Keirstead and others have been taking to regenerate damaged spinal cords is to restore the myelin sheaths to, or “remyelinate,” the neurons. This has been primarily accomplished by introducing new oligodendrocytes to the damaged spinal cord area.

Keirstead continued developing methods of treating spinal cord injuries using oligodendrocytes, but started incorporating human embryonic stem cells (hESCs) into his approaches when he joined the Reeve-Irvine Research Center at UC Irvine. Four years after joining the Reeve Center, in 2005, Keirstead reported that his group could not only create oligodendrocyte progenitors from hESCs, but could also use these progenitors to effectively treat rats with acute spinal cord injuries. (This was published in The Journal of Neuroscience). Specifically, when these rats were injected with oligodendrocyte progenitor cells (termed OPCs) made from hESCs, the rats were able to remyelinate neurons and improve motor functions.

Human embryonic stem cells have immense potential for the field of regenerative medicine because they are seemingly unlimited in numbers and are pluripotent (meaning they can become any type of cell), but they have also been surrounded by ethical debate due to their biological origins. And, other than stem cells from fetal tissues (fetal mesenchymal stem cells specifically, which are from a much later stage in development than hESCs are) or neural stem cells (which are obviously quite limited in supply), hESCs are the only type of stem cell that has been found to be able to become oligodendrocytes (or oligodendrocyte progenitors). Consequently, hESCs are currently the best source of these cells for spinal cord therapies. And they appear to be quite effective.

On January 23, 2009, after submitting very promising data from 24 studies in animals in a 21,000-page application (hopefully it didn’t need to be printed!), Keirstead and collaborators at the biopharmaceutical company Geron received FDA approval for the first-ever human trials using hESCs.

The Phase I clinical trials were to treat patients with subacute thoracic spinal cord injuries by injecting the hESC-derived OPCs (labeled “GRNOPC1”) into the site of injury in the patient’s spinal cord, as this method showed significantly improved neuron remyelination and locomotion in animals for over nine months after a single injection with OPCs. Seven medical centers in the U.S. were selected for the clinical trial, and eligible patients would have to have had a spinal cord injury between the T3 and T10 thoracic spinal segments (near the middle of the spinal cord) and be able to be treated with OPCs only 7 to 14 days after the injury. The short time window of eligibility for treatment is clearly an aspect requiring improvement, but reflects what was observed in the animal models: quick action is needed after injury for these methods to be effective. Hopefully future approaches can be developed, or current ones improved upon, to increase the time window of treatment.

However, in August 2009, before any patients had actually been treated, the trial was put on hold by the FDA. Additional animal data submitted by Geron revealed that small, non-proliferative (they do not grow) cysts were found in the injury site, although the presence of these cysts did not correlate with animals having negative side effects. In late October, 2009 Geron announced that it would reinitiate Phase I clinical trials in patients with thoracic spinal cord injuries, and might expand them to include patients with cervical (the top part of the spinal cord) injuries in the future. The trials are expected to reinitiate by July 2010, while current studies are further characterizing the OPCs in animal studies. Geron is also currently exploring the applicability of the OPCs in treating other neurological diseases, such as Alzheimer’s disease, strokes, and multiple sclerosis.

The University of California at Santa Barbara is becoming a hub for stem cell research that is transitioning to the clinic. Interdisciplinary groups on campus collaborate and use human embryonic stem cells for regenerative medicine applications in the UCSB Center for Stem Cell Biology and Engineering. Additionally, Dr. James Thomson, the researcher who originally isolated hESCs in 1998, holds a joint faculty appointment at the University of Wisconsin and UCSB. Clearly, UCSB is at the forefront of a wave of burgeoning stem cell facilities, and Dr. Keirstead’s talk should find a receptive and motivated audience.

As knowledge and awareness of the uses of these very promising stem cells continues to grow, the resistance they originally met with has already been diminishing. Collaborative efforts with biopharmaceutical companies may ultimately be key to demonstrating the true potential of these cells in treating human diseases and injuries, such as the work done by Keirstead and his Geron collaborators has shown. To hear more about these efforts from Hans Keirstead directly, attend his June 14 presentation here in Santa Barbara .

For more on Dr. Hans Keirstead and his research, see the California Stem Cell’s profile on Keirstead, UC Irvine’s profile on Keirstead, Keirstead’s 2005 paper on using hESC-derived oligodendrocyte progenitors to treat spinal cord injuries, Geron’s press release on the FDA approval for clinically using these cells, the FDA placing the clinical trial on hold in August 2009, or the FDA/Geron announcement to reinitiate the clinical trial in 2010.

Biology Bytes author Teisha Rowland is a science writer, blogger at All Things Stem Cell, and graduate student in molecular, cellular, and developmental biology at UCSB, where she studies stem cells. Send any ideas for future columns to her at Această adresă de email este protejată contra spambots. Trebuie să activați JavaScript pentru a o vedea..

http://www.independent.com/news/2010/jun/04/night-dr-hans-keirstead/
***

Pe 23 Ianuarie 2009, le-a fost aprobat testul clinic, dar a fost pus in asteptare in august 2009 de catre FDA, deoarece datorita informatiilor ulterioare aduse de Geron, privind rezulatetele lor pe sobolani, se formasera chisturi in maduva sobolanilor, chiar daca nu se semnalasera efecte negative.

In Octombrie 2009, Geron a anuntat, ca ar putea reincepe testul clinic, candva in iulie 2010. Nu stiu daca au inceput.

E vorba de cazuri de TVM toracice, imediat dupa accident. Si testul clinic in Faza 1 are in vedere sa stabileasca "siguranta" transplantului de celule stem embrionare. Nu se testeaza eficacitatea.

Nu se incearca creerea de noi neuroni, ci e vorba de creerea unui nou strat de mielina, neuronilor care au supravietuit leziunii, asta putand aduce doar ameliorari conditiei pacientilor.

Sa vedem ce va mai fi cu acest test clinic. Va mai dura pana vor aparea rezultate concludente. Cam asta am inteles eu din articolele de mai sus. Corectati-ma unde gresesc.
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Re:Geron - test clinic cu celule stem embrionare acum 6 ani 5 luni #17297

Am terminat de tradus, si prezentarea lui Hans Keirstead. Chiar daca e din 2008, zic eu ca merita vazuta. Spor.


Hans Keirstead, PhD: "Challenges to the Clinical Viability of Stem Cell Technologies."



http://www.trilulilu.ro/Eqqqu/bbd9aaaf91c3f6
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Re:Geron - test clinic cu celule stem embrionare acum 6 ani 4 luni #17378

Aici e subtitrarea, daca o vrea cineva:

Fisier atasat:

Nume fișier: hans_autocorrect_final.txt
Dimensiune fișier: 66672
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Re:Geron - test clinic cu celule stem embrionare acum 6 ani 4 luni #17786

Acelasi video de mai sus, incarcat la youtube, pentru ai putea face embed:





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Re:Geron - test clinic cu celule stem embrionare acum 6 ani 4 luni #17787

Dupa cum spuneam mai sus, testul clinic fusese pus in asteptare de catre FDA.

Stirea de ultima ora, e ca vineri li s-a dat unda verde de catre FDA, si vor reincepe testul clinic probabil in septembrie. Anuntul a fost facut vineri 30 iulie, si ziarele au inceput acum sa scrie despre asta. Cred ca va aparea si-n ziarele romanesti in zilele urmatoare.

Dati un search la google news si vedeti. Redau doar un articol din Financial Times:

"Geron given FDA go-ahead for stem cells trial

By Clive Cookson in London

Published: July 30 2010 19:29 | Last updated: July 30 2010 19:29

The world’s first treatment based on human embryonic stem cells is set to begin a clinical trial within the next two months, in patients with acute spinal cord injury.

Geron, a Californian biotech company, announced on Friday that the US Food and Drug Administration would allow the trial to proceed without any further delay. Last year the FDA put Geron’s trial “on clinical hold” because of safety concerns raised by one of the animal studies used to support the application. Further testing on rats has addressed those concerns.

The product, known as GRNOPC1, consists of immature nerve cells grown from stem cells that were derived originally from human embryos at a very early stage of development.

The cells will be injected into the damaged spinal cord of accident victims. If the cells behave in people as they have done in animals with spinal injury, they will partially repair the damaged nerves and restore some movement to paralysed patients.

“The neurosurgical community is ready to begin the clinical testing of this new approach to treating devastating spinal cord injury,” said Richard Fessler, professor of neurological surgery at Northwestern University in Chicago. “If found to be safe and effective, the therapy would provide a viable treatment option for thousands of patients who suffer severe spinal cord injuries each year.”

Embryonic stem cells can potentially be guided to become almost any human tissue, which gives them great potential in “regenerative medicine”.

But their original creation from human embryos has made them politically and ethically controversial, particularly in the US where the Bush administration severely restricted their creation for research.

Other researchers working on stem cells in universities and industry are keen for Geron’s clinical trial to start, because successful results would give a huge boost to the whole field.

William Caldwell, chief executive of Advanced Cell Technology, a Massachusetts stem cell company, said: “We are very excited that Geron was able to overcome the issues raised by the FDA and can now move ahead with clinical trials. The whole industry needs wins.”

ACT has asked the FDA for permission to start treating patients who suffer from Stargardt’s macular dystrophy, a form of blindness, with retinal cells derived from human embryonic stem cells.

But the agency has asked the company for further safety data.

Copyright The Financial Times Limited 2010. You may share using our article tools. Please don't cut articles from FT.com and redistribute by email or post to the web."

http://www.ft.com/cms/s/0/322baf24-9c01-11df-a7a4-00144feab49a.html?ftcamp=rss

Asta e un pas in directia cea buna.

Asta e pagina de pe site-ul Geron in care se vorbeste despre acest test:

http://www.geron.com/GRNOPC1Trial/
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Re:Geron - test clinic cu celule stem embrionare acum 6 ani 4 luni #17827

Azi a aparut stirea si-n ziarele romanesti. Eu am gasit-o in doua ziare crestine. Dar probabil ar trebui sa fie si la celelalte agentii de stiri. Totusi eu nu am reusit sa o gasesc. Fiti atenti ce poza au bagat cei cu primul articol:

Articol 1.

A fost aprobat primul tratament cu celule stem embrionare pe subiecți umani

2 august 2010

În America a fost aprobată prima tentativă clinică de terapie cu celule stem embrionare asupra unui subiect uman. Compania californiană Geron Corporation a primit undă verde pentru tratamentul unor pacienți cu probleme la coloană. Speranța este aceea că injectarea unui tratament pe bază de celule stem va ajuta la creșterea din nou a celulelor nervoase și va permite pacienților să-și recapete capacitatea motorie.


Autoritatea americană The U.S. Food and Drug Administration (FDA) a aprobat vineri cererea companiei, după ce aprobase inițial studiul în ianuarie 2009. Geron a descoperit însă că animalele testate în studiile preclinice au dezvoltat chisturi „într-o frecvență mai mare" decât în urma altor studii. Ca urmare, tentativa a fost amânată un an de zile, din vara lui 2009.


stem_cell_400.gif
Cercetarea bazată pe celule stem este controversată, pentru că implică distrugerea embrionului în timpul colectării celulelor stem. Multe grupări pro-life consideră acțiunea lipsită de etică, echivalând-o cu avortul. Opțiunea ar fi cercetarea cu celule stem prelevate de la adulți. Susținătorii metodei afirmă că celulele stem sunt foarte versatile, putându-se dezvolta în orice țesut în organism.


Sub administrația Bush, cercetarea celulelor stem embrionice a fost restricționată. În administrația Obama, cercetarea a primit libertăți mult mai mari. Geron va începe tratamentele anul acesta, fără să fi indicat o dată exactă. San Jose Mercury News afirmă că Geron a cheltuit peste 150 de milioane de dolari, pentru această cercetare, în decursul ultimilor 15 ani.

Sursa: "Semnele Timpului - revista de analiza si opinie crestina"

***

Articol 2.

Vaticanul considera "inacceptabile" testele clinice pe oameni, cu celule stem provenite din embrioni umani
Monday, 02 August 2010 12:36

Lacasuri Ortodoxe: din Vatican
Vaticanul considera "inacceptabile" testele clinice pe oameni, cu celule stem provenite din embrioni umani

Vaticanul a numit sâmbătă, 31 iulie 2010, "inacceptabilă" unda verde acordată testelor clinice ale SUA, cu celule stem umane derivate din embrioni umani.

©Un articol pentru Lacasuri Ortodoxe: Bogdan Roman

Într-o emisiune a Radioului Vatican, monseniorul Elio Sgreccia, preşedintele emerit al Academiei Pontificale pentru Viaţă, a atras atenţia asupra unei evaluări mai “etice” a noii decizii.



Compania Geron din SUA a anunţat vineri, 30 iulie 2010, că a fost autorizată de Food and Drug Administration (FDA) să efectueze primele teste clinice pe oameni, în lume, folosindu-se de tratamente bazate pe celule stem derivate din embrioni.



Chiar dacă refuză aceste tratamente, Biserica Catolică nu se opune însă cercetărilor pe celule provenite din cordonul ombilical sau adulte provenite, de exemplu, din intestin sau retină.

articol publicat in paginile scrise MONITOR Lacasuri Ortodoxe® nr. 29/2010
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Re:Geron - test clinic cu celule stem embrionare acum 6 ani 4 luni #17844

Doresc sa mai fac o precizare. Am prezentat cele doua articole de mai sus, ca sa arat mai mult cum stirea este modificata dupa traducere, sau mai putin inteleasa.

Asteptam sa apara si-un articol mai bine scris in ziarele romanesti, dar inca nu am gasit asa ceva.

Cei de la "Semnele Timpului" spun:

"Speranța este aceea că injectarea unui tratament pe bază de celule stem va ajuta la creșterea din nou a celulelor nervoase și va permite pacienților să-și recapete capacitatea motorie."

Cei de la Geron, preleveaza celule stem embrionare, dupa care in laborator, le deriveaza, obtinund un anumit tip de celule. Toata ideea e cum sa faci, ca din celulele stem, sa obtii un anume tip de celule specializate.

Ei au reusit sa deriveze celule oligodendrocite, din celule stem embrionare. Conteaza sa obtina ceva de o inalta puritate.

Ei vor implanta celule oligodendrocite precursoare [precursoare --adica din care se vor forma oligodendrocite], in maduva pacientilor cu tvm acut care au o leziune prin contuzie, pentru remielinizarea axonilor care si-au pierdut stratul de mielina in urma accidentului.

Ce sunt celulele oligodendrocite? By the way, oligodendrocite si oligondendroglii, sunt unul si acelasi lucru.



"Oligodendrogliile se ocupa cu sintetizarea tecii de mielina. Acestea sunt mai mici decat astrocitele. Prelungirile sunt mai numeroase si mai scurte spre deosebire de cele prezente la astrocite.
Oligodendrogliile sunt prezente atat in substanta alba cat si in substanta cenusie. Prelungirile lor nu vin in contact cu capilarele, intre ele intrepunandu-se prelungirile lamelare ale astrocitelor."

Vedeti articolul despre tipuri de neuroni si celule gliale de aici: http://www.prostemcell.ro/54-sfaturi-si-intrebari/4640-corpul-omenesc.html

Oricum daca urmariti videoul intelegeti mai bine despre ce e vorba. Asta e o poza de la Geron, din care se intelege destul de bine despre ce e vorba:



Nu fac nimic pentru a fixa cavitatea. Incearca sa remielinizeze axonii, care au supravietuit.


Au derivat si neuroni motori, dar aia urmau sa-i testeze in amiotrofie spinala tip 1. Nu stiu daca au inceput vreun test clinic in sensu ala.

La conferinta din Taiwan a Spinal Cord Workshop de anul asta, a fost si un reprezentat de la Geron. Sa vedem cand incarca videourile.


Pana una alta, ziarele noastre se axeaza pe "problema etica", punand poze cu fetusi. :angry:
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Re:Geron - test clinic cu celule stem embrionare acum 6 ani 1 lună #19183

SUA: Primul pacient tratat cu celule embrionare umane

Medicii americani au tratat in premiera medicala internationala un pacient cu ajutorul celulelor stem recoltate de pe embrioni umani, in cadrul unui test clinic realizat cu permisiunea autoritatilor, a anuntat luni compania de biotehnologie Geron Corporation, transmite AFP, preluata de Agerpres (11 octombrie).

"Startul testului clinic GRNOPC1 reprezinta o etapa importanta pentru terapiile umane bazate pe celule stem embrionare" subliniaza intr-un comunicat Dr Thomas Okarma, din cadrul Geron Co.

Principalul obiectiv al acestui test clinic aflat in prima faza este de a evalua siguranta tratamentului si toleranta organismului fata de aceste celule derivate din celule stem embrionare denumite GRNOPC1, la persoanele paralizate in urma unor accidente asupra coloanei vertebrale.

Pacientii participanti la acest test au suferit accidente la coloana in urma cu scurt timp si primesc tratamentul cu GRNOPC1 timp de 14 zile.

Primul dintre pacienti a fost selectionat din centrul de reabilitare Shepherd, din Atlanta (Georgia, sud-est). Pacientii paralizati care participa la test sunt injectati cu celule stem embrionare umane (GRNOPC1) in speranta ca acestea vor putea regenera celulele nervoase distruse dupa accident, si, potential, sa-i permita persoanei paralizate sa-si recapete macar partial simturile pierdute si capacitatea de a se misca.
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Rasp: Re:Geron - test clinic cu celule stem embrionare acum 5 ani 5 luni #22299

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