Webmedcentral - Embryology ArticlesThe Embryology articles published by Webmedcentral
http://www.webmedcentral.com
2024-03-29T05:03:36+01:00webmedcentral logo
http://www.webmedcentral.com/
http://www.webmedcentral.com/images/Header_Logo.giftext/html2011-09-26T14:55:18+01:00http://www.webmedcentral.com/Dr. Mahdi EsmaeilzadehHoly Quran, New Sciences and Development of Human Embryo
http://www.webmedcentral.com/article_view/2260
Ever since the dawn of human life on this planet, Man has always tried to understand Nature, his own place in the scheme of Creation and the purpose of Life itself. In this quest for Truth, spanning many centuries and diverse civilizations, organized religion has shaped human life and, to a large extent, has determined the course of history. While some religions have been based on written text, claimed by their followers to be divinely inspired, others have relied solely on human experience.Al-Qur'an, the main source of the Islamic faith, is a book believed by its followers, the Muslims, to be completely of Divine origin. Muslims also believe that it contains guidance for all humankind. Since the message of the Qur'an is believed to be for all times, it should be relevant to every age.This article highlights different stages of formation of the human embryo along with the description of every stage of the embryonic development as mentioned in the Quran. This study shows that God creates a child in a mother's womb and brings about the child chronological evolution to full life, while the parents only play an instrumental role in this creative process. The Quran says: We have created man out of an extraction of clay (the origin of semen). Then we turn it into semen and settle it in a firm receptacle. We then turn semen into a clot (‘alaqah) (literally, something hanging, that is, from the womb) which we then transmute into a lump (mudghah). We then create bones which we clothe with flesh. Then, we transmute it into a new mode (of ensoulment)-blessed be then Allah, the best of creators. (Al-Quran, Surah (Chapter) Al-Mu'minun (23): 12-14, see also Al-Hajj (22): 5).Key words: Holy Quran, Development, Human Embryo, science.text/html2012-04-24T18:07:40+01:00http://www.webmedcentral.com/Dr. Antony J DurstonHox Homeotic Selector Genes: Key Regulators of Embryogenesis
http://www.webmedcentral.com/article_view/3277
The Hox genes are major regulators of the animal bodyplan. They determine the identities of sequential zones along the main body axis. The Hox genes show collinearity– spatial and temporal ordering of their expression corresponding to their genomic order- a spectacular phenomenon that has excited life scientists since its discovery in 1978. Three mechanisms have been proposed to explain this spatially sequential axial pattern of Hox gene expression in animal embryonic development:1) That it is secondary and regulated by other spatially ordered genes.2) That it is regulated by interactions among Hox genes, or3) It is regulated by the progressive opening of chromatin in the Hox clusters, from 3’ to 5’.A review of the evidence across different species and developmental stages points to the universal involvement of trans-acting factors and cell–cell interactions. The evidence focuses attention on interactions between Hox genes and on the vertebrate somitogenesis clock. These novel conclusions open new perspectives for the field.text/html2013-10-15T07:18:36+01:00http://www.webmedcentral.com/Dr. Kang ChengMemory and Control Models of Evo-Geno and Evo-Devo
http://www.webmedcentral.com/article_view/4425
What steers evolution? The answers are not clear at cellular and molecular levels in a perspective of biomedical infophysics today.
In this article, we define memory as stored information (SI) that can be remembered and recalled to respond to other memories or information; a cell as a memory unit; DNA genes, mRNA, proteins and other cellular components as sub-memory units.
Correspondently, we define inherited memories (IM) as that obtained through genetic procedure (e.g., cellular fertilization, division or proliferation) and acquired memories (AM) as that obtained from the extra cellular environments (e.g., external DNA, RNA, proteins or other components); the memory intensity (MI) as stored information intensity (SII), such as the electric field intensity (EFI) and the gravitational field intensity (GFI); memory response intensity (MRI) as stored information response intensity (SIRI), such as forces or energies.
We define three types of sub-cellular memories: the static are stored in genes (sets) in DNA strands, the dynamic are stored in RNA (sets) and the functional are stored in proteins (sets). We think memories include spatial and temporal fields or virtual particles, such as the electric (major), magnetic (minor) and the gravitational (inconsiderable), as well as the structured matters (represented with charges and masses).
We classify cellular stabilities as inner and external cellular stabilities. We define, inner cellular stability as inheritance fidelity of DNA genome in divided cells, external cellular stability as contact inhibition of divided cells; a complete stability means the both inner and external stabilities are satisfied; controllability as that normal parent cells are divided into normal children cells; convergence as that the final divided cells become the differentiated and (or) apoptosis (programmed death) or necrosis. The programmed death is electromagnetically or mostly electrically encoded.
Based on the definitions, our previous works and published data, we propose our memory and control models of Evo-Geno and Evo-Devo (evolutionary genome and evolutionary development) of species. We assume the correspondent environments (including nutrients) in the two reference frames of Evo-Geno and Evo-Devo are (almost) the same or similar and the correspondent memory sets are also (almost) the same or similar. Therefore, we hypothesize; the recalling orders of cellular memory sets during human Evo-Devo are the same as the remembering orders of cellular memory sets during human Evo-Geno. I.e., the first remembered memory set is first recalled; the second remembered memory set is second recalled; and the last remembered memory set is last recalled; for the transcription and the expression. The cells memories remember the orders.