MolBiol.ru > > > | |
|
ר
|
EDTA => 1V, proteinase K 50µg/ml, |
: / /
|
, , guest: /24.06.2006 15:23/
[font=Arial][size=1][color=maroon] vb /08.08.2006 09:09/
( ) . ( .. , - " "), ( 30 ) . - (, , , , ) . - ( ) - . : 1. - ( )? 2. (-70) 5 . ? , , ? 3. , , ( ) , ? 4. , - (1:1). , . .., - ? ? 5. , - (24:1). ? 6. , ? 7. - , ? . ? Guest /08.08.2006 12:19/
1. . - 2. , , 3. , 4. , , 5. 6. " " 7. , - . /08.08.2006 16:11/
, - . vb /08.08.2006 19:48/
/09.08.2006 07:22/
( ). , ( ). quiagen DNeasy. . . . , . . , , . . Anubis /15.08.2006 01:41/
vb /15.08.2006 07:35/
, ? , . nikolya2 /14.09.2006 15:42/
, : ; 0.5M EDTA 50mM => 1/10V; 0,8 V Tris Cl pH7.6 5mM ( 1M), proteinase K 50g/ml,SDS 10% 1% (1/10V) 50 . ... nikolya2 /14.09.2006 15:51/
molbiol.ru, . /Kola/. 100% ! 2 nikolya2 /14.09.2006 16:02/
11 . , . . , . 12 - 96% -20 . , 1 ( , ), . Guest /21.09.2006 12:14/
- 20 H + 60% 200 1:10 DNAzol Direct Guest /21.09.2006 12:28/
CGH microarray - ( Guest /21.09.2006 12:31/
8-G - (( (( (( Guest /21.09.2006 12:35/
(8-oxoG) Guest /21.09.2006 12:40/
"" "" /18.10.2006 11:07/
, - , ? Guest /07.02.2007 16:40/
! , , , , -. . 5 ml. , , . guest: /07.02.2007 20:27/
! . Diatom DNA Prep. . . Guest /08.02.2007 12:00/
. 5 , , , 200 . , , . Guest /08.02.2007 12:58/
? ? ? 1 . "Magnetic DNA Prep 1". , 2-10 . Guest /08.02.2007 13:37/
. , . /19.02.2007 11:57/
Promega. , 4-5 . Guest /21.02.2007 13:49/
/15.03.2007 19:00/
. 5 , , , 200 . , , . QIAGEN Max - , /12.05.2007 16:25/
, -, ? ? , ? /13.05.2007 22:55/
Guest /14.05.2007 08:01/
( @ 12.05.2007 16:25) 1: Proc Natl Acad Sci U S A. 2000 Nov 7;97(23):12800-3.Click here to read Click here to read Links Molecular identification by "suicide PCR" of Yersinia pestis as the agent of medieval black death. * Raoult D, * Aboudharam G, * Crubezy E, * Larrouy G, * Ludes B, * Drancourt M. Centre National de la Recherche Scientifique Unite Propre de Recherche de l'Enseignement Superieur (UPRES)-A 6020, Faculte de Medecine, Universite de la Mediterranee, 13385 Marseille, France. Didier.Raoult@medicine.univmrs.fr Medieval Black Death is believed to have killed up to one-third of the Western European population during the 14th century. It was identified as plague at this time, but recently the causative organism was debated because no definitive evidence has been obtained to confirm the role of Yersinia pestis as the agent of plague. We obtained the teeth of a child and two adults from a 14th century grave in France, disrupted them to obtain the pulp, and applied the new "suicide PCR" protocol in which the primers are used only once. There were no positive controls: Neither Yersinia nor Yersinia DNA were introduced in the laboratory. A negative result is followed by a new test using other primers; a positive result is followed by sequencing. The second and third primer pair used, coding for a part of the pla gene, generated amplicons whose sequence confirmed that it was Y. pestis in 1 tooth from the child and 19/19 teeth from the adults. Negative controls were negative. Attempts to detect the putative alternative etiologic agents Bacillus anthracis and Rickettsia prowazekii failed. Suicide PCR avoids any risk of contamination as it uses a single-shot primer-its specificity is absolute. We believe that we can end the controversy: Medieval Black Death was plague. Guest /14.05.2007 08:02/
( @ 12.05.2007 16:25) Guest /15.05.2007 21:57/
/15.05.2007 22:47/
Guest /16.05.2007 07:04/
Guest /16.05.2007 07:18/
Guest /16.05.2007 07:19/
(Guest @ 16.05.2007 07:18) Restorase DNA Polymerase PCR Sigma's Restorase DNA Polymerase (R1028) is a specialty enzyme designed to facilitate repair and provide reliable amplification of damaged DNA. Extensive manipulation of DNA that results from archived samples, aged museum specimens, or samples from phenol/chloroform extraction, causes damage that interferes with accurate amplification during PCR. Restorase was developed for researchers unable to achieve amplification of damaged DNA templates when using other commercially available DNA polymerases. The ability to restore damaged or degraded DNA enables researchers to work with damaged templates that would otherwise be abandoned. Guest /16.05.2007 07:30/
( @ 15.05.2007 22:47) - 1: Proc Natl Acad Sci U S A. 2007 Jan 16;104(3):739-44. Epub 2007 Jan 8.Click here to read Links Freshly excavated fossil bones are best for amplification of ancient DNA. * Pruvost M, * Schwarz R, * Correia VB, * Champlot S, * Braguier S, * Morel N, * Fernandez-Jalvo Y, * Grange T, * Geigl EM. Institut Jacques Monod, Tour 43, 2 Place Jussieu, 75005 Paris, France. Despite the enormous potential of analyses of ancient DNA for phylogeographic studies of past populations, the impact these analyses, most of which are performed with fossil samples from natural history museum collections, has been limited to some extent by the inefficient recovery of ancient genetic material. Here we show that the standard storage conditions and/or treatments of fossil bones in these collections can be detrimental to DNA survival. Using a quantitative paleogenetic analysis of 247 herbivore fossil bones up to 50,000 years old and originating from 60 different archeological and paleontological contexts, we demonstrate that freshly excavated and nontreated unwashed bones contain six times more DNA and yield twice as many authentic DNA sequences as bones treated with standard procedures. This effect was even more pronounced with bones from one Neolithic site, where only freshly excavated bones yielded results. Finally, we compared the DNA content in the fossil bones of one animal, a approximately 3,200-year-old aurochs, excavated in two separate seasons 57 years apart. Whereas the washed museum-stored fossil bones did not permit any DNA amplification, all recently excavated bones yielded authentic aurochs sequences. We established that during the 57 years when the aurochs bones were stored in a collection, at least as much amplifiable DNA was lost as during the previous 3,200 years of burial. This result calls for a revision of the postexcavation treatment of fossil bones to better preserve the genetic heritage of past life forms. PMID: 17210911 [PubMed - indexed for MEDLINE] Guest /16.05.2007 07:35/
(Guest @ 16.05.2007 07:04) 1: Mol Biol Evol. 2006 Sep;23(9):1801-7. Epub 2006 Jun 29.Click here to read Links Tracking down human contamination in ancient human teeth. * Sampietro ML, * Gilbert MT, * Lao O, * Caramelli D, * Lari M, * Bertranpetit J, * Lalueza-Fox C. Unitat de Biologia Evolutiva, Departament de Ciencies Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain. DNA contamination arising from the manipulation of ancient calcified tissue samples is a poorly understood, yet fundamental, problem that affects the reliability of ancient DNA (aDNA) studies. We have typed the mitochondrial DNA hypervariable region I of the only 6 people involved in the excavation, washing, and subsequent anthropological and genetic study of 23 Neolithic remains excavated from Granollers (Barcelona, Spain) and searched for their presence among the 572 clones generated during the aDNA analyses of teeth from these samples. Of the cloned sequences, 17.13% could be unambiguously identified as contaminants, with those derived from the people involved in the retrieval and washing of the remains present in higher frequencies than those of the anthropologist and genetic researchers. This finding confirms, for the first time, previous hypotheses that teeth samples are most susceptible to contamination at their initial excavation. More worrying, the cloned contaminant sequences exhibit substitutions that can be attributed to DNA damage after the contamination event, and we demonstrate that the level of such damage increases with time: contaminants that are >10 years old have approximately 5 times more damage than those that are recent. Furthermore, we demonstrate that in this data set, the damage rate of the old contaminant sequences is indistinguishable from that of the endogenous DNA sequences. As such, the commonly used argument that miscoding lesions observed among cloned aDNA sequences can be used to support data authenticity is misleading in scenarios where the presence of old contaminant sequences is possible. We argue therefore that the typing of those involved in the manipulation of the ancient human specimens is critical in order to ensure that generated results are accurate. PMID: 16809622 [PubMed - indexed for MEDLINE] Guest /16.05.2007 07:43/
(Guest @ 16.05.2007 07:04) 1: Mol Biol Evol. 2005 Oct;22(10):2040-7. Epub 2005 Jun 15.Click here to read Links Extensive human DNA contamination in extracts from ancient dog bones and teeth. * Malmstrom H, * Stora J, * Dalen L, * Holmlund G, * Gotherstrom A. Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden. helena.malmstrom@ebc.uu.se Ancient DNA (aDNA) sequences, especially those of human origin, are notoriously difficult to analyze due to molecular damage and exogenous DNA contamination. Relatively few systematic studies have focused on this problem. Here we investigate the extent and origin of human DNA contamination in the most frequently used sources for aDNA studies, that is, bones and teeth from museum collections. To distinguish contaminant DNA from authentic DNA we extracted DNA from dog (Canis familiaris) specimens. We monitored the presence of a 148-bp human-specific and a 152-bp dog-specific mitochondrial DNA (mtDNA) fragment in DNA extracts as well as in negative controls. The total number of human and dog template molecules were quantified using real-time polymerase chain reaction (PCR), and the sequences were characterized by amplicon cloning and sequencing. Although standard precautions to avoid contamination were taken, we found that all samples from the 29 dog specimens contained human DNA, often at levels exceeding the amount of authentic ancient dog DNA. The level of contaminating human DNA was also significantly higher in the dog extracts than in the negative controls, and an experimental setup indicated that this was not caused by the carrier effect. This suggests that the contaminating human DNA mainly originated from the dog bones rather than from laboratory procedures. When cloned, fragments within a contaminated PCR product generally displayed several different sequences, although one haplotype was often found in majority. This leads us to believe that recognized criteria for authenticating aDNA cannot separate contamination from ancient human DNA the way they are presently used. /16.05.2007 12:45/
Guest /16.05.2007 12:50/
/16.05.2007 13:40/
Guest /18.05.2007 15:30/
Guest /18.05.2007 15:48/
( @ 16.05.2007 13:40) /18.05.2007 18:43/
/18.05.2007 19:35/
(Guest @ 18.05.2007 15:48) , Guest /19.05.2007 09:49/
Guest /19.05.2007 11:06/
( @ 18.05.2007 18:43) /19.05.2007 12:18/
(Guest @ 19.05.2007 11:06) . . Guest /19.05.2007 18:49/
( @ 19.05.2007 12:18) 30 - /19.05.2007 19:39/
Guest /20.05.2007 09:53/
guest: /26.10.2007 11:28/
! , - , . /26.10.2007 18:06/
, . /06.11.2007 00:15/
, . . . . , . - , CsCl c . . /06.11.2007 00:47/
pantera /12.02.2008 12:15/
! , (QIAamp DNA Mini Kits) 96-100%, . , , - , ? , ? )) /29.03.2008 12:20/
, ? ? The problem /29.03.2008 13:44/
Yuri K /31.03.2008 17:16/
(Guest @ 20.05.2007 08:53) You do not need to know Alfred Nobel, of course, since your chance of getting the prize in his name are nil; but what about Jerker Porath and Christian Anfinsen, who was Norwegian by origin? /05.09.2008 05:46/
, -, ? ? .... Guest1 /05.09.2008 10:43/
Guest /05.09.2008 12:44/
Guest1 /05.09.2008 14:08/
Guest /05.09.2008 14:38/
/22.09.2008 13:01/
? , ? ON NT ? /22.09.2008 18:46/
guest: /22.09.2008 19:45/
- ""? . -- ON NT ? ON - , . NT - . -- , ? . 20 , . /23.09.2008 09:01/
Guest1 /23.09.2008 09:29/
/23.09.2008 10:20/
Guest1 /23.09.2008 13:02/
/23.09.2008 17:02/
Guest1 /23.09.2008 17:31/
/23.09.2008 20:57/
/23.09.2008 20:58/
Guest /24.09.2008 09:33/
Guest /24.09.2008 09:35/
Guest1 /24.09.2008 10:25/
/24.09.2008 10:56/
Guest1 /24.09.2008 13:28/
Guest /06.01.2009 15:58/
( @ 24.09.2008 09:56) , Fe3O4 - , Fe2O3, - . - ( ) . Sod /06.01.2009 18:16/
, , . FeO . FeO . Guest1 /16.03.2009 11:16/
Leshiy-lyosha /27.12.2011 14:16/
- , +4 ? guest: /27.12.2011 16:54/
- - , +4 ? ! kblag /28.12.2011 11:04/
-- /28.12.2011 17:57/
bee1 /28.12.2011 18:13/
bee1 /28.12.2011 18:17/
- - bee1 /28.12.2011 19:31/
bee1 /28.12.2011 19:41/
bee1 /28.12.2011 19:53/
bee1 /28.12.2011 20:12/
volmin /17.11.2019 06:12/
watchesbiz /03.11.2021 17:05/
|
ר
|