scholarly journals Epigenetics: Switching Genes On and Off

2020 ◽  
Vol 8 ◽  
Author(s):  
Maria-Cecilia D. Costa ◽  
Frank Johannes
Keyword(s):  
Human Cell ◽  
Genetic Information ◽  
Fast Growing ◽  
Dna Organization ◽  
End To End

The DNA of a human cell has all the information necessary to produce more than 20,400 different proteins. This information is written in an amount of DNA that, if stretched end-to-end, would measure about one meter. You can imagine how challenging it is to keep all this information in an organized way. Other animals, bacteria, and plants face the very same challenge. The solutions to the problem of DNA organization found by cells include tightly packing the DNA and switching genes “on” and “off” as needed. The study of these switches is called epigenetics. Epigenetics is a fast-growing field of research that is changing our understanding of genetic information.

INBORN ERRORS OF METABOLISM: SOME THOUGHTS ABOUT THEIR BASIC MECHANISMS

PEDIATRICS ◽  
1970 ◽  
Vol 45 (6) ◽  
pp. 901-905
Author(s):  
R. Rodney Howell
Keyword(s):  
Human Cell ◽  
Genetic Information ◽  
Inborn Errors Of Metabolism ◽  
Inborn Errors ◽  
Current Time ◽  
Correct Information ◽  
The Future ◽  
Structural Mutations

The question of whether, in the inborn errors of metabolism, genetic information is absent or coded incorrectly (structural mutations), or whether the gene itself is normal but is not activated (regulatory defects) is extremely important in the directions taken for the future consideration of such problems. The problem of introducing new, well defined, genetic information into a human cell which is either lacking such information or has abnormal genetic information appears formidable at the current time. However, the existence of regulatory defects would imply that the correct information to make the deficient enzyme (s) is available to the cell, and we need only find ways of activating (inducing) this genetic information.

Discrimination of monomer from multimer DNA disk-shaped toruses by freezeetch TEM

1984 ◽  
Vol 42 ◽  
pp. 210-211
Author(s):  
George C. Ruben ◽  
Kenneth A. Marx
Keyword(s):  
Biochemical Data ◽  
Dna Structures ◽  
Ice Surface ◽  
Double Stranded Dna ◽  
Data Support ◽  
Dna Organization ◽  
Trivalent Cations

In vitro collapse of DNA by trivalent cations like spermidine produces torus (donut) shaped DNA structures thought to have a DNA organization similar to certain double stranded DNA bacteriophage and viruses. This has prompted our studies of these structures using freeze-etch low Pt-C metal (9Å) replica TEM. With a variety of DNAs the TEM and biochemical data support a circumferential DNA winding model for hydrated DNA torus organization. Since toruses are almost invariably oriented nearly horizontal to the ice surface one of the most accessible parameters of a torus population is annulus (ring) thickness. We have tabulated this parameter for populations of both nicked, circular (Fig. 1: n=63) and linear (n=40: data not shown) ϕX-174 DNA toruses. In both cases, as can be noted in Fig. 1, there appears to be a compact grouping of toruses possessing smaller dimensions separated from a dispersed population possessing considerably larger dimensions.

Torus Circumference and Thickness Parameters From a Linear DNA Size Series Suggest How Toruses Self-Assemble

1985 ◽  
Vol 43 ◽  
pp. 522-523
Author(s):  
George C. Ruben ◽  
Kenneth A. Marx
Keyword(s):  
Tertiary Structure ◽  
Dna Complexes ◽  
Tertiary Structures ◽  
Self Assembling ◽  
Double Stranded Dna ◽  
Calf Thymus ◽  
Dna Organization ◽  
Condensed Dna ◽  
Dna Size

Certain double stranded DNA bacteriophage and viruses are thought to have their DNA organized into large torus shaped structures. Morphologically, these poorly understood biological DNA tertiary structures resemble spermidine-condensed DNA complexes formed in vitro in the total absence of other macromolecules normally synthesized by the pathogens for the purpose of their own DNA packaging. Therefore, we have studied the tertiary structure of these self-assembling torus shaped spermidine- DNA complexes in a series of reports. Using freeze-etch, low Pt-C metal (10-15Å) replicas, we have visualized the microscopic DNA organization of both calf Thymus( CT) and linear 0X-174 RFII DNA toruses. In these structures DNA is circumferentially wound, continuously, around the torus into a semi-crystalline, hexagonal packed array of parallel DNA helix sections.

New Rules Address Use of Genetic Information

2009 ◽  
Vol 42 (19) ◽  
pp. 11
Author(s):  
MARY ELLEN SCHNEIDER
Keyword(s):  
Genetic Information

Surgical management of extracranial carotid artery aneurysms

VASA ◽  
2016 ◽  
Vol 45 (3) ◽  
pp. 223-228 ◽  
Author(s):  
Jan Paweł Skóra ◽  
Jacek Kurcz ◽  
Krzysztof Korta ◽  
Przemysław Szyber ◽  
Tadeusz Andrzej Dorobisz ◽  
...  
Keyword(s):  
Carotid Artery ◽  
Surgical Management ◽  
Minor Stroke ◽  
Stroke Rate ◽  
Extracranial Carotid Artery ◽  
Long Term Follow Up ◽  
End To End ◽  
Dacron Patch ◽  
Major Stroke

Abstract. Background: We present the methods and results of the surgical management of extracranial carotid artery aneurysms (ECCA). Postoperative complications including early and late neurological events were analysed. Correlation between reconstruction techniques and morphology of ECCA was assessed in this retrospective study. Patients and methods: In total, 32 reconstructions of ECCA were performed in 31 symptomatic patients with a mean age of 59.2 (range 33 - 84) years. The causes of ECCA were divided among atherosclerosis (n = 25; 78.1 %), previous carotid endarterectomy with Dacron patch (n = 4; 12.5 %), iatrogenic injury (n = 2; 6.3 %) and infection (n = 1; 3.1 %). In 23 cases, intervention consisted of carotid bypass. Aneurysmectomy with end-to-end suture was performed in 4 cases. Aneurysmal resection with patching was done in 2 cases and aneurysmorrhaphy without patching in another 2 cases. In 1 case, ligature of the internal carotid artery (ICA) was required. Results: Technical success defined as the preservation of ICA patency was achieved in 31 cases (96.9 %). There was one perioperative death due to major stroke (3.1 %). Two cases of minor stroke occurred in the 30-day observation period (6.3 %). Three patients had a transient hypoglossal nerve palsy that subsided spontaneously (9.4 %). At a mean long-term follow-up of 68 months, there were no major or minor ipsilateral strokes or surgery-related deaths reported. In all 30 surviving patients (96.9 %), long-term clinical outcomes were free from ipsilateral neurological symptoms. Conclusions: Open surgery is a relatively safe method in the therapy of ECCA. Surgical repair of ECCAs can be associated with an acceptable major stroke rate and moderate minor stroke rate. Complication-free long-term outcomes can be achieved in as many as 96.9 % of patients. Aneurysmectomy with end-to-end anastomosis or bypass surgery can be implemented during open repair of ECCA.

Reliability of the Mangled Extremity Severity Score in the Management of Peripheral Vascular Injuries in Children: A Retrospective Review

2020 ◽  
Author(s):  
Ahmed Mousa ◽  
Ossama M. Zakaria ◽  
Mai A. Elkalla ◽  
Lotfy A. Abdelsattar ◽  
Hamad Al-Game'a
Keyword(s):  
Severity Score ◽  
Vein Graft ◽  
Bypass Surgery ◽  
Age Groups ◽  
Vascular Injuries ◽  
Peripheral Vascular ◽  
Group Iii ◽  
Mangled Extremity ◽  
Group I ◽  
End To End

AbstractThis study was aimed to evaluate different management modalities for peripheral vascular trauma in children, with the aid of the Mangled Extremity Severity Score (MESS). A single-center retrospective analysis took place between 2010 and 2017 at University Hospitals, having emergencies and critical care centers. Different types of vascular repair were adopted by skillful vascular experts and highly trained pediatric surgeons. Patients were divided into three different age groups. Group I included those children between 5 and 10 years; group II involved pediatrics between 11 and 15 years; while children between 16 and 21 years participated in group III. We recruited 183 children with peripheral vascular injuries. They were 87% males and 13% females, with the mean age of 14.72 ± 04. Arteriorrhaphy was performed in 32%; end-to-end anastomosis and natural vein graft were adopted in 40.5 and 49%, respectively. On the other hand, 10.5% underwent bypass surgery. The age groups I and II are highly susceptible to penetrating trauma (p = 0.001), while patients with an extreme age (i.e., group III) are more susceptible to blunt injury (p = 0.001). The MESS has a significant correlation to both age groups I and II (p = 0.001). Vein patch angioplasty and end-to-end primary repair should be adopted as the main treatment options for the repair of extremity vascular injuries in children. Moreover, other treatment modalities, such as repair with autologous vein graft/bypass surgery, may be adopted whenever possible. They are cost-effective, reliable, and simple techniques with fewer postoperative complication, especially in poor/limited resources.

Fast-Growing China's Hydropower Systems and Operation Challenges

2011 ◽  
Author(s):  
Chun-Tian Cheng ◽  
K. W. Chau ◽  
Xin-Yu Wu ◽  
Jian-Jian Shen
Keyword(s):  
Fast Growing

Modern university as an economic growth driver: Models & missions

2017 ◽  
pp. 58-76 ◽  
Author(s):  
A. Karpov
Keyword(s):  
Economic Growth ◽  
Education Research ◽  
Advanced Technology ◽  
Global Competitiveness ◽  
Technology Markets ◽  
Fast Growing ◽  
Business Ecosystem ◽  
Cost Efficient ◽  
National Economies ◽  
The University

The paper considers the modern university as an economic growth driver within the University 3.0 concept (education, research, and commercialization of knowledge). It demonstrates how the University 3.0 is becoming the basis for global competitiveness of national economies and international alliances, and how its business ecosystem generates new fast-growing industries, advanced technology markets and cost-efficient administrative territories.

Characteristics, Features of Development, Regional and Sectoral Determinants of High-tech Business in Russia

2017 ◽  
pp. 142-154 ◽  
Author(s):  
A. Yusupova ◽  
S. Khalimova
Keyword(s):  
Regression Analysis ◽  
Performance Indicators ◽  
Sustainability Assessment ◽  
Business Development ◽  
High Tech ◽  
Assessment Data ◽  
High Tech Sector ◽  
Fast Growing ◽  
High Level

The paper deals with the research devoted to characteristics of high tech business development in Russia. Companies’ performance indicators have been analyzed with the help of regression analysis and author’s scheme of leadership stability and sustainability assessment. Data provided by Russia’s Fast Growing High-Tech Companies’ National Rating (TechUp) during 2012-2016 were used. The results have revealed that the high tech sector is characterized by high level of uncertainty. Limited number of regions and sectors which form the basis for high tech business have been defined. Relationship between innovation activity’s indicators and export potential is determined.

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