Infobox Embryology Name Blastocyst Latin GraySubject GrayPage Image Blastocyst English.svg Caption Image2 Caption2 System CarnegieStage 3 Days 5 Precursor Morula GivesRiseTo Gastrula MeshName Blastocyst MeshNumber A16.254.085 DorlandsPre b 14 DorlandsSuf 12187695 File PorcineBlastocyst.jpg thumb A pig blastocyst. The bar is 0.1 mm. See also Blastocystis , a single celled parasite. The blastocyst is a structure formed in the early embryogenesis of mammal s, after the formation of the morula . It is a specifically mammalian example of a blastula . citation needed date January 2011 It possesses an inner cell mass ICM , or inner cell mass embryoblast , which subsequently forms the embryo , and an outer layer of cells, or trophoblast , which later forms the placenta . The trophoblast surrounds the inner cell mass and a fluid filled blastocyst cavity known as the blastocoele or the blastocystic cavity. The human blastocyst comprises 70 100 Cell biology cells . Blastocyst formation begins at day 5 after fertilization in humans, when the blastocoele opens up in the morula. citation needed date January 2011 Parts of the blastocyst The blastocyst consists of two primary cell types the inner cell mass , also known as the embryoblast this part of the embryo is used in stem cell research the trophoblast , a layer of cells surrounding the inner cell mass and the blastocyst cavity blastocoele .... Formation of the blastocyst The morula is a solid ball of about 16 undifferentiated, spherical cells ... glycoproteins. References reflist External links http www.hfea.gov.uk blastocyst transfer.html Blastocyst transfer and fertility treatment http www.oneatatime.org.uk 330.htm Risks of blastocyst transfer http www.advancedfertility.com blastocystimages.htm Blastocyst photos at different stages of development ... noteblog anatomy section2 anatomy of blastocyst.php Blastocyst Differentiation Diagram ... es Blastocisto fr Blastocyste hi it Blastocisti nl Blastocyste ja no Blastocyst pl ... more details
Summary Image of human blastocyst showing Inner Cell Mass top, right and Trophectoderm. Source http stemcells.nih.gov info scireport chapter3.asp Licensing PD USGov NIH ... more details
Zona hatching is a phenomenon occurring during prenatal development . Prior to this event, the predecessor of the embryo, in the form of a blastocyst , is surrounded by a glycoprotein sphere called the zona pellucida . To be able to perform Implantation human embryo implantation on the uterine wall, the blastocyst first needs to get rid of the zona pellucida ref http www.ivf infertility.com ivf hatching.php IVF infertility.com ref . This lysis of the zona pellucida is called the zona hatching. Uses of the term In some situations, the term hatching is used only for artificial ways to free the blastocyst from the zona pellucida, and not the natural lysis of it. An example of such artificial way is Assisted zona hatching . References references Category embryology ... more details
Infobox Embryology Name Blastocoele Latin GraySubject GrayPage Image Blastocyst.gif Caption Blastocyst Image2 Blastocyst English.svg Caption2 Blastocyst with an inner cell mass and trophoblast . System CarnegieStage 3 Days 5 Precursor morula GivesRiseTo primitive yolk sac MeshName MeshNumber DorlandsPre b 14 DorlandsSuf 12187664 A blastocoel e or blastocele also called blastocyst cavity , ref cite web url http www.embryology.ch anglais iperiodembry carnegie02.html title The Carnegie stages accessdate 2007 10 13 format work ref cleavage cavity or segmentation cavity is the fluid filled central region of a blastocyst . A blastocoele forms during embryogenesis when a zygote a fertilized ovum divides into many cells through mitosis . The adjective adjectival of blastocoel e is blastocoelic . A blastocoel can be described as the first cell cavity formed as the embryo enlarges. It is essential for later gastrulation . References references See also Embryo Embryology Category Developmental biology developmental biology stub cs Blastocoel de Blastocoel es Blastocele fr Blastoc le it Blastocele ja pl Blastocel pt Blastoc lio ru tr Blastos l ... more details
is a blastocyst . It is by this adhesion that the fetus receives the oxygen and the nutrients from ... and take the polyhedral shape characteristic for decidual cells. Trigger It is likely that the blastocyst ... substances. Mechanism Implantation is initiated when the blastocyst comes into contact with the uterine wall. Zona hatching Main Zona hatching To be able to perform implantation, the blastocyst first ... in the uterine cavity, as well as factors from the blastocyst itself are essential for this process ... is plasmin . Plasminogen , the plasmin precursor, is found in the uterine cavity, and blastocyst ... the blastocyst and the endometrium is called the apposition. ref name boron Location On the endometrium ... the area of contact with the rather spherical blastocyst. On the blastocyst, on the other hand, it occurs ... closest to the decidua. Nevertheless, the apposition on the blastocyst is not dependent on if it is on the same side of the blastocyst as the inner cell mass. Rather, the inner cell mass rotates inside the trophoblast to align to the apposition. ref name boron In short, the entire surface of the blastocyst ... the blastocyst and the endometrium at this stage. The blastocyst signals to the endometrium to adapt ... the blastocyst to perform the succeeding invasion. ref name boron This communication is conveyed by receptor ..., are found around the trophoblast cells of the blastocyst. This ligand receptor system also is present ... of the blastocyst in the endometrium. Syncytiotrophoblasts The protrusions of trophoblast cells ... of forming the placenta . Secretions The blastocyst secretes factors for a multitude of purposes ... menstruation. Autocrine Human chorionic gonadotropin is an autocrine growth factor for the blastocyst ... Factors from the blastocyst also trigger the final formation of decidual cells into their proper form. In contrast, some decidual cells in the proximity of the blastocyst degenerate, providing ... Other factors secreted by the blastocyst are ovum factor Embryo derived histamine releasing factor ... more details
The pluriblast is a Pluripotency pluripotent population of Cell biology cells in the early mammal ian conceptus that is distinct from the trophoblast , and gives rise to the germ layer s of the embryo proper , as well as extraembryonic endoderm and extraembryonic mesoderm . Both the pluriblast and trophoblast arise from the Totipotency totipotent cells of the early conceptus. By definition, the pluriblast does not give rise to trophoblast cells during normal development, although it may retain this potential under experimental conditions. In most eutheria n mammals the pluriblast is termed the inner cell mass , as it forms a mass of cells within the fluid filled blastocyst , bounded by the trophoblast. However in metatherian marsupial mammals, and indeed in a small number of eutherian mammals, the pluriblast forms part of the blastocyst wall and no structure exists that can be described as an inner cell mass. Inner cell mass is thus a morphological term peculiar to the majority of eutherian mammals, whereas pluriblast is a functional term more widely applicable to conserved aspects of mammalian development. References Johnson MH and Selwood L 1996 . Nomenclature of early development in mammals. Reproduction, Fertility and Development. 8 759 764. Category Developmental biology ... more details
Assisted zona hatching AZH is a procedure of Assisted reproductive technology , increasing the chances of pregnancy ref name IVF http www.ivf infertility.com ivf hatching.php IVF infertility.com ref . Indication Normally, the blastocyst performs zona hatching , getting rid of the surrounding zona pellucida , to be able to implant in the uterus. However, sometimes this zona pellucida is toughened, disabling the embryo to hatch. In these cases, AZH is needed. Procedure A small hole is made in the zona pellucida, using a micromanipulation. This facilitates zona hatching to occur ref name IVF . References references Assisted reproductive technology DEFAULTSORT Assisted Zona Hatching Category Human reproduction medical stub ... more details
Immunosurgery is a method of removing an external cell biology cell layer of an object. Immunosurgery is to expose the specimen to a solution containing antibodies against the object, remove that solution and subsequently expose the object to Complement system complement . When only the external layer is marked with antibodies, these cells are the only ones to be destroyed by the complement. This technique is used to isolate the inner cell mass of mouse blastocyst s from the trophoblast layer. It can be used to obtain large quantities of pure inner cell masses in a relatively short period of time. ref cite pmid 1108013 ref References reflist immunology stub surgery stub biology stub Category Immunology Category surgery ... more details
embryo, reached after four to six days, is the blastocyst akin to the blastula stage , and lasts ... to be selected and then transferred to the mother s uterus . Blastocyst differentiation File Blastocyst English.svg right thumb 200px Blastocyst with an inner cell mass and trophoblast . The blastocyst ... embryoblast and the mentioned trophoblast the outer cells , and a blastocyst cavity blastocoel . The inner ... will eventually form the placenta . The blastocyst can be thought of as a ball of a mostly ... . The zona pellucida ultimately disappears completely, allowing the blastocyst to invade ... implants the blastocyst in the endometrium innermost epithelium epithelial lining of the uterus ... cells the hypoblast is closest to the blastocyst cavity, and made of cuboidal cells. The epiblast ... wgbh nova miracle images stem blastocyst.jpg Photo of blastocyst in utero Slideshow http www.lifehugger.com ... more details
Does severe teratozoospermia affect blastocyst formation, live birth rate, and other clinical outcome ... sperm morphology does not appear to influence blastocyst development or blastocyst morphology ... more details
Summary Information Description A porcine blastocyst developed from embryos reconstituted with confluent adult somatic cells and enucleated M I oocytes matured in a protein free medium. Bar 100 m. Source cite journal author Miyoshi K, Rzucidlo SJ, Gibbons JR, Arat S, Stice SL title Development of porcine embryos reconstituted with somatic cells and enucleated metaphase I and II oocytes matured in a protein free medium journal BMC Dev. Biol. volume 1 issue pages 12 year 2001 pmid 11476669 pmc 35352 doi url http www.biomedcentral.com 1471 213X 1 12 date 2001 Author Miyoshi K, Rzucidlo SJ, Gibbons JR, Arat S, Stice SL Licensing cc by 2.0 ... more details
Germinal choice technology refers to a set of reprogenetic technologies that, currently or that are expected to in the future, allow parents to influence the genotype genetic constitution s of their children. This could be done through genetic screening of blastocyst s early embryo s , or through germline engineering , which refers to human genetic engineering used to alter gene s in the first cells of the blastocyst. ref name Wagner 2002 cite paper author Wagner, Cynthia G. title Germinal Choice Technology Our Evolutionary Future. An Interview with Gregory Stock date 2002 url http www.wfs.org intstock.htm accessdate 2006 02 21 ref Screening technologies have been in use since at least the mid 1990s to reduce the incidence of genetic disorders , and what can be tested for is expected to become increasingly sophisticated in the early 2010 s Citation needed date March 2011 . Maturation in these fields would increase the range and sophistication of decisions open to parents. Germline engineering and even the engineering of human artificial chromosome s which presently allow increased reliability are presently being done in animals. References reflist refbegin Paul, Diane B. 2002 . http www.americanscientist.org template BookReviewTypeDetail assetid 17662 Swashbuckling into the Nebulous Future . American Scientist . criticism refend See also Procreative liberty Procreative beneficence Category Biotechnology Category Bioethics Category Genetic engineering Category Molecular genetics Category Human reproduction biotech stub ar ... more details
as a blastocyst . The presence of the blastocyst means that two types of cells are forming ... to 48 hours, the zona pellucida breaches. The cells on the exterior of the blastocyst begin .... Placental circulation system The cells surrounding the blastocyst now destroy cells in the uterine ... stage in the growth of the placenta . The inner cell mass of the blastocyst divides ... site. The small sac inside the blastocyst begins producing red blood cell s. For the next 24 hours ... more details
Infobox Embryology Name Inner cell mass Latin GraySubject 6 GrayPage 46 Image Blastocyst English.svg Caption Blastocyst with an inner cell mass and trophoblast . Image2 Caption2 System CarnegieStage 3 Days 6 Precursor blastocyst GivesRiseTo epiblast , hypoblast MeshName MeshNumber DorlandsPre m 04 DorlandsSuf 12515766 In early embryogenesis of most eutherian mammals, the inner cell mass abbreviated ICM and also known as the embryoblast or pluriblast , the latter term being applicable to all mammals is the mass of cells inside the primordial embryo that will eventually give rise to the definitive structures of the fetus. This structure forms in the earliest steps of development, before Implantation human embryo implantation into the endometrium of the uterus has occurred. The ICM lies within the blastocoele more correctly termed blastocyst cavity, as it is not strictly homologous to the blastocoele of anamniotes anamniote vertebrates and is entirely surrounded by the single layer of cells called trophoblast . Further development The physical and functional separation of the inner cell mass from the trophectoderm TE is a special feature of mammalian development and is the first cell lineage specification in these embryos. Following fertilization in the oviduct, the mammalian embryo .... This results in a polarization of the cells within the morula, and further cleavage yields a blastocyst ..., these cells pump fluid into the interior of the blastocyst, causing the formation of a polarized blastocyst ... segregation of pluripotent cells of the inner cell mass from the remainder of the blastocyst is integral ... compaction, but lose the TE epithelial integrity during the late blastocyst stage. Furthermore ... fate specification and differentiation of trophectoderm in the mouse blastocyst. Development 132 2093 ... axis of the mouse blastocyst relationships between orientation of early cleavage divisions and pattern ... blastocyst, and their transcriptional code governed by Oct4 , Sox2 , and Nanog helps maintain ... more details
Mammalian embryogenesis is the process of cell division and cellular differentiation during early prenatal development which leads to the development of a mammal ian embryo . Difference from human embryogenesis Main Human embryogenesis Most mammal s develop similarly to Homo sapiens during the earliest stages of development, the embryo is largely indistinguishable from another mammal. However, there are phenomena found in human beings not found in all other mammals, as well as phenomena occurring in other mammals, but not in humans. Humans Mammals do not necessarily have the same human chorionic gonadotropin released from their embryo. Non human mammals The anatomy of the area surrounding an embryo or fetus, however, is different in litter bearing animals compared to humans each unborn animal is surrounded by placental tissue and is lodged along one of two long uterine horns rather than in the center of the pear shaped uterus found in a human female. See also Embryogenesis Drosophila embryogenesis Plant embryogenesis Developmental biology Blastomere Morula Cdx2 External links http www.pbs.org wgbh nova miracle images stem blastocyst.jpg Photo of blastocyst in utero Unreferenced date January 2008 Embryology Category Developmental biology ar de Blastozyste fr Blastocyste nl Blastocyste tr Blastokist ... more details
Infobox Embryology Name Blastula GraySubject GrayPage Image Blastulation.png Caption Blastulation 1 morula, 2 blastula. Image2 Caption2 System CarnegieStage Days 4 Precursor GivesRiseTo MeshName MeshNumber DorlandsPre b 14 DorlandsSuf 12188083 Image Blastula PSF .jpg right 200px The blastula from Greek blastos , meaning sprout is a solid sphere of cell biology cell s formed during an early stage of embryonic development in animals . The blastula is created when the zygote undergoes the cell division process known as cleavage embryo cleavage . ref Forg cs & Newman, 2005 http books.google.com books?id rUyVWQhk7CkC&pg PA24 p. 24 ref The blastula is preceded by the morula and precedes the gastrula in the developmental sequence. citation needed date January 2011 A common feature of a vertebrate blastula is that it consists of a layer of blastomeres , known as the blastoderm , which surrounds an interior central cavity known as the blastocoel . ref cite book author Lombardi, Julian chapter Embryogenesis title Comparative vertebrate reproduction publisher Springer year 1998 isbn 9780792383369 page 226 url http books.google.com books?id cqQX9RMPAegC&pg PA226 ref ref Forg cs & Newman, 2005 http books.google.com books?id rUyVWQhk7CkC&pg PA27 p. 27 ref In mammal s, blastulation leads to the formation of the blastocyst , which must not be confused with the blastula. The blastocyst contains an embryoblast , which is homologous to the blastula. However, it also includes the trophoblast , which goes on to form the extraembryonic tissues. citation needed date January 2011 See also Cellular differentiation Gastrulation Polarity in embryogenesis References Notes reflist Bibliography cite book authors Forg cs, G. & Newman, Stuart A. chapter Cleavage and blastula formation title Biological physics of the developing embryo publisher Cambridge University Press year 2005 isbn 9780521783378 url http books.google.com books?id rUyVWQhk7CkC&pg PA24 Further reading cite book author Cul ... more details
Su Chun Zhang born 1963 in Wenzhou , Zhejiang , is an United States American stem cell researcher at the University of Wisconsin Madison . Biography Zhang obtained MD from the Wenzhou Medical College , Wenzhou, and PhD from the University of Saskatchewan , Canada . Zhang presently is Professor of Anatomy and Neurology and a research group leader at the University of Wisconsin Madison. In January 2005, Zhang s group differentiated human blastocyst stem cells into neural stem cells, then further into the starts of motor neuron s, and eventually into spinal motor neuron cells which play important role in delivering information from the brain to the spinal cord in the human body . The artificially generated motor neurons exhibited profiles the same as those normal natural ones, including functions like electrophysiological activity which is the signature of neuron s. Zhang described this study as ... you need to teach the blastocyst stem cells to change step by step, where each step has different conditions and a strict window of time . This research would have high significance for those human diseases or injuries related to spinal cord or motor neurons. Zhang s next step focused on the communicational ability of these newly generated neurons when they are transplanted into a living vertebrate . ref http www.alsa.org research grant.cfm?id 166 Generation of Human Motor Neurons from Stem Cells ref See also Stem cell treatments Neural stem cells development and transplantation Chapter 10 Neuronal Replacement by Transplantation by Daniel J. Guillaume and Su Chun Zhang https www.wicell.org index.php?option com docman&task doc download&gid 236 Generating motor neurons References references External links http www.waisman.wisc.edu FACULTY ZHANG.HTML Prof. Zhang Waisman Center, UW M http www.cmb.wisc.edu node 216 Zhang Lab UW M http ntp.neuroscience.wisc.edu faculty zhang.html Su Chun Zhang Neuroscience Training Program http aging.senate.gov minority files hr142sz.pdf Explorin ... more details
, forming a hollow ball of cells known as the blastocyst . ref Cite book author Patestas, Maria ... authors Geisert, R.D. & Malayer, J.R. chapter Implantation Blastocyst formation editors Hafez, B ... 9780683305777 page 118 url http books.google.com books?id baz2TC1y2esC&pg PA118 ref The blastocyst s outer ... more details
Infobox Embryology Name Trophoblast Latin GraySubject 6 GrayPage 46 Image Blastocyst English.svg Caption Blastocyst with an inner cell mass and trophoblast. Image2 Gray32.png Caption2 Section through ovum imbedded in the uterine decidua. Semidiagrammatic. BR BR am. Amniotic cavity . BR b.c. Blood clot . BR b.s. Body stalk . BR ect. Embryonic ectoderm . BR ent. Entoderm . BR mes. Mesoderm . BR m.v. Maternal vessels . BR tr. Trophoblast. BR u.e. Uterine epithelium . BR u.g. Uterine glands . BR y.s. Yolk sac . System CarnegieStage Days 6 Precursor GivesRiseTo caul MeshName Trophoblasts MeshNumber A16.254.085.162 DorlandsPre DorlandsSuf Trophoblasts from Greek language Greek trephein to feed, and blastos germinator are cells forming the outer layer of a blastocyst , which provide nutrients to the embryo and develop into a large part of the placenta . They are formed during the first stage of pregnancy and are the first cells to cellular differentiation differentiate from the fertilized ovum egg . This layer of trophoblasts is also collectively referred to as the trophoblast , ref http www.britannica.com EBchecked topic 606502 trophoblast ref or, after gastrulation , ref http www.merriam webster.com medical trophectoderm Merriam Webster s Medical Dictionary trophectoderm Retrieved August 2010 ref the trophectoderm , as it is then continuous with the ectoderm of the embryo. Function Trophoblasts are specialised cells of the placenta that play an important role in embryo implantation and interaction with the decidualised maternal uterus. The core of placental villi contain mesenchymal cells and placental blood vessels that are directly connected to the fetal circulation via the umbilical cord. This core is surrounded by two layers of trophoblast a single layer of mononuclear cytotrophoblast that fuse together to form the overlying multinucleated syncytiotrophoblast layer that covers the entire surface of the placenta. It is this syncytiotrophoblast that is in direct contact ... more details
The laws and policies regarding stem cell research in the People s Republic of China are relatively relaxed in comparison to that of other nations. The reason for this is due to different traditional and cultural views in relation to that of the West. Laws and regulations China has one of the most unrestrictive embryonic stem cell research policies in the world. In recent years, seeing the research opportunities that China s lax regulations provide, many expatriate Chinese scientists from the West are returning to China to establish stem cell research centers and laboratories there. ref cite journal journal Nature journal Nature title China Stem cells rise in the East volume 419 issue 6905 last Dennis first Carina doi 10.1038 419334a year 2002 pages 334 pmid 12353004 ref As a result of the increased interest in this field of research, in 2003, the People s Republic of China Ministry of Science and Technology and Ministry of Health issued official ethical guidelines for human embryonic stem cell research in its territories. The guidelines strictly forbid any research aimed at human reproductive cloning and require that the embryos used for stem cell research come only from Spared gamate or blastocyst after in vitro fertilization in vitro fertilization IVF procedures Fetal cells from accidental spontaneous or voluntarily selected abortions Blastocyst or parthenogenetic split blastocyst obtained by somatic cell nuclear transfer technology or Germ cells voluntarily donated. ref cite web url http www.chinaphs.org bioethics regulations & laws.htm Toc113106142 title Regulations & Laws date 18 March 2007 accessdate 24 April 2009 publisher Bioethics Network in China ref American scientific journals Science and Nature have both reported in recent years that China s stem cell programs hold potential, and in 2004 a delegation from Britain s Department of Trade and Industry concluded more emphatically that Chinese research in the field was already world class. ref name nejm cite ... more details
Megan and Morag , two domestic sheep , were the first mammals to have been successfully cloning cloned from differentiated cells. They are not to be confused with Dolly the Sheep which was the first animal to be successfully cloned from an adult somatic cell or Polly the sheep which was the first cloned and transgenic animal. Megan and Morag, like Dolly the Sheep and Polly the sheep were cloned at the Roslin Institute in Edinburgh , Scotland in 1995. Background The team at the Roslin Institute were seeking a way to modify the genetic constitution of sheep and cattle more effectively than the hit and miss method that was the only method and had sort of aids available at the time Microinjection . In Microinjection , DNA is injected into the pronucleii of fertilized oocytes. However, only a small proportion of the animals will integrate the injected DNA into their genome and in the rare cases that they do integrate this new genetic information, the pattern of expression of the injected piece of DNA s gene, due to the random integration, is very variable. The team choose to combine two approaches Microinjection and Embryonic stem cells . In order to achieve this they decided to try to transfer the nucleus from one cell to another and stimulate this new cell to grow and become an animal, a process known as Nuclear transfer . The team at the Roslin Institute tried to make immortalized and undifferentiated Embryonic stem cell lines in sheep, but failed. As a result they decided to work with cultured blastocyst cells. The nuclear material of these blastocyst cells would be transferred into an unfertilized sheep egg cell, an oocyte where the nucleus had been removed. To optimize the chances of successful nuclear transfer , they put the cultured cells into a state of quiescence, which was a similar state to that of the unfertilized egg cell. Nuclear transfer was done, using electrical stimuli both to fuse the cultured cell with the enucleated egg and to kick start embryonic d ... more details
Infobox Embryology Name PAGENAME Latin GraySubject 12 GrayPage 56 Image Gray31.png Caption Model of human embryo 1.3 mm. long. Image2 Caption2 System CarnegieStage 5a Days Precursor GivesRiseTo MeshName MeshNumber DorlandsPre c 16 DorlandsSuf 12220728 The amniotic cavity is the closed sac between the embryo and the amnion, containing the amniotic fluid. The amniotic cavity is formed by the fusion of the parts of the amniotic fold, which first makes its appearance at the cephalic extremity, and subsequently at the caudal end and sides of the embryo . As the amniotic fold rises and fuses over the dorsal aspect of the embryo, the amniotic cavity is formed. Formation of the Amniotic Cavity At the beginning of the second week, a cavity appears within the inner cell mass and when it enlarges it becomes the Amniotic cavity. The floor of the amniotic cavity is formed by the epiblast. Epiblast migrates between the epiblastic disc and trophoblast. In this way the epiblastic cells migrate between the embryoblast and trophoblast . The floor is formed by the epiblast which later on transforms to ectoderm while the remaining cells which are present between the embryoblast and trophoblast are called amnioblasts flattened Cells . These cells are also derived from epiblast which is transformed into ectoderm. The amniotic cavity is surrounded by a membrane, called the amnion. As the implantation of the blastocyst progresses, a small space appears in the embryoblast, which is the primordium of the amniotic cavity. Soon amniogenic Amnion forming cells amnioblasts separate from the epiblast and line the amnion, which encloses the amniotic cavity. The epiblast forms the floor of the amniotic cavity and is continuous peripherally with the amnion. The hypoblast forms the roof of the exocoelomic cavity and is continuous with the thin exocoelomic membrane. This membrane along with hypoblast forms the primary yolk sac. The embryonic disc now lies between the amniotic cavity and the primary yo ... more details
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