mutation theory
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Author(s):  
Li-Yuan Liu

Although Darwin‘s evolutionary mutation theory has been widely accepted, many endeavors tried to challenge it. With more and more observation of successful hybridization and hybrids, the sexual isolation between species has become vague. The mechanism of evolution has been expanded from the classical model of evolution to multiple routes of speciation. Furthermore, a fundamental crossbreeding theory has been raised and proved by two lines of evidences: paleopolyploidy and fan-shaped spectrum of species. Ancient genome duplications are widespread throughout eukaryotic lineages, particularly in plants. The genome polyploidization can break through the sexual incompatibility between diploid counterparts to hybridize and produce new species. By comparing characteristics, all species in every taxon, both in the extinct fossil and extant organisms, can be arranged into fan-shaped spectrum according to their similarity: left primitive type-middle advanced type-right primitive type. The species are primitive at the two ends and advanced at the middle. The primitive two species always resemble two types of more primitive species that can be confirmed as their ancestors respectively, and the middle species is half similar to the two ancestors respectively. These suggest that the species in the spectrum come from two different ancestors by crossbreeding and gene combination. As a sum, advanced species originated from crossbreeding of two primitive ancestors, by major method of polyploidization, and proved by results of fan-shaped spectrum of species. Then, sex is the cause, force and opportunity for evolution.


Author(s):  
Elia Biganzoli ◽  
Romano Demicheli

The paradigm of the Somatic Mutation Theory (SMT) is failing, and a new paradigm is underway but not yet established. What is being challenged is a conceptual approach that involves the entire human biology and the development of chronic diseases. The behavior of breast and other solid cancers is compatible with the concept that the primary tumor is able to control its microscopic metastases, in the same way that an organ (e.g., the liver) is able to control its physiological size. This finding suggested that cancer and its metastases may behave as an organoid. The new paradigm under construction considers the origin of tumors as a disturbance in the communication network between tissue cell populations and between cells and extracellular matrix, and supports a systemic approach to the study of both healthy and pathologic tissues. The commentary provides a rationale for the role of physical exercise in the control of tumor dormancy according to a human evolutionary perspective.


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Jianping Gao ◽  
Sijie Zhang ◽  
Yunyong He ◽  
Qi Zhang ◽  
Lu Sun ◽  
...  

A real-world driving experiment was performed in the Wen-Ma section of the G4217 Rong-Chang Freeway situated in the Sichuan Province to investigate the impact law of the pupil diameter of drivers in tunnel groups on the mountainous freeway. The eye-movement data of drivers were collected, and the percentage of pupil diameter variable (PPDV) was used as a visual characteristic index. The analysis of the overall change in the PPDV of drivers in the experimental sections demonstrated that the PPDV in tunnel groups differed significantly between the nontunnel sections and single tunnel sections. Subsequently, a related model for the PPDV of drivers and the length of the connecting zone between tunnels was established, its reliability evaluated, and the smooth mutation value obtained on the basis of the mutation theory. Thereafter, a tunnel group definition standard based on the visual effect of drivers was developed. A six-zone approach was devised for the analysis of tunnel groups, and the result revealed that the different zones in the tunnel group have different impact on PPDV of drivers. The results revealed that the different zones of tunnel group have different impact on PPDV of drivers. Furthermore, lighting transition facilities should be set in the exit section of tunnel. The PPDV of drivers was negatively correlated with the length of the connecting zone of tunnel groups, and 100 m is the recommended safety length threshold for the connecting zone of tunnel groups.


Author(s):  
Elia Biganzoli ◽  
Romano Demicheli

The paradigm of the Somatic Mutation Theory (SMT) is failing and a new paradigm is in the making but not yet established. What is being challenged is a conceptual approach that involves the entire human biology and the development of chronic diseases. The behavior of breast cancer is well compatible with the concept that the primary tumor is able to control its microscopic metastases, in the same way that an organ (e.g., the liver) is able to control its physiological size. This finding suggested that breast cancer and its metastases may behave as an organoid. The new paradigm under construction considers the origin of tumors as a disturbance in the communication network between tissue cell populations and between cells and extracellular matrix, and supports a systemic approach to the study of both healthy and pathologic tissues. The commentary provides a rationale for the role of physical exercise in the control of tumor dormancy according to a human evolutionary perspective.


2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Xiaojiao Wang ◽  
Dan Luo ◽  
Sisi Wu

Atherosclerosis is a chronic lipid-driven inflammatory disease that results in the formation of lipid-rich and immune cell-rich plaques in the arterial wall, which has high morbidity and mortality in the world. The mechanism of atherosclerosis is still unclear now. Potential hypotheses involved in atherosclerosis are chronic inflammation theory, lipid percolation theory, mononuclear-macrophage theory, endothelial cell (EC) injury theory, and smooth muscle cell (SMC) mutation theory. Changes of phospholipids, glucose, critical proteins, etc. on mitochondria-associated endoplasmic reticulum membrane (MAM) can cause the progress of atherosclerosis. This review describes the structural and functional interaction between mitochondria and endoplasmic reticulum (ER) and explains the role of critical molecules in the structure of MAM during atherosclerosis.


Cancers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 2026
Author(s):  
Romano Demicheli ◽  
Elia Biganzoli

The problem of late recurrence in breast cancer has recently gained attention and was also addressed in an international workshop held in Toronto (ON, Canada), in which several aspects of the question were examined. This Commentary offers a few considerations, which may be useful for the ongoing investigations. A few premises are discussed: (a) clinical recurrences, especially the late ones, imply periods of tumor dormancy; (b) a structured pattern of distant metastases appearance is detectable in both early and late follow-up times; (c) the current general paradigm underlying neoplastic treatments, i.e., that killing all cancer cells is the only way to control the disease, which is strictly sprouting from the somatic mutation theory, should be re-considered. Finally, a few research approaches are suggested.


2021 ◽  
Vol 38 ◽  
pp. 91-112
Author(s):  
Sandro Secutti ◽  
Eleonora Trajano

The troglobitic (exclusively subterranean source population) catfish Ituglanis passensis (Siluriformes, Trichomycteridae) is endemic to the Passa Três Cave, São Domingos karst area, Rio Tocantins basin, Central Brazil. This unique population presents variably reduced eyes and melanic pigmentation. We describe reproduction and early development in this species based on a spontaneous (non-induced) reproductive-event that occurred in the laboratory in January–February, 2009, while simultaneously comparing with data from the cave-habitat and a previous reproductive event. Egg laying was parceled. Egg-size and number were within variations observed in epigean congeners. Larvae behavior and growth is described. A single surviving specimen was monitored over two years. Eye-regression started late, one year after birth, and followed a pattern of stasis phases intercalated with slow growth and fluctuating asymmetric rates. Late eye regression, associated with asymmetry in eye development and intra-population variability of troglomorphic traits, as shown by several Brazilian subterranean fishes, provide support for the Neutral Mutation Theory.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Adeleh Khodabakhshi ◽  
Maryam Mahmoudi ◽  
Hassan Mehrad Majd ◽  
Sayed Hossein Davoodi

Context: Somatic mutation theory has been considered as a potential cause for cancer. However, major inconsistencies with the gene theory have necessitated serious reconsideration of this assumption. According to these inconsistencies, cancer may be considered as a metabolic disorder. According to the mitochondrial metabolic theory, substrate-level phosphorylation has been suggested to be superior to oxidative phosphorylation in cancer cells. Cancer metabolic therapies such as ketogenic diets (KD) and limitation in glutamine and calorie can be beneficial and are in line with this theory. In this study, we have reviewed the potential effects of KD as well as glutamine and calorie restriction in various types/stages of cancer with a focus on possible mechanisms. Evidence Acquisition: A comprehensive electronic search of different databases was performed using “cancer”, “ketogenic diet”, and “metabolic” as the main keywords. A comprehensive electronic search of different databases was performed using “cancer”, “ketogenic diet”, and “metabolic” as the main keywords. Results: Emerging evidence has indicated that KD can affect tumor cells by reducing glucose availability and simultaneous elevation of ketone bodies as non-fermentable metabolic fuels. KD has been suggested to be more effective as a non-toxic therapeutic measure in combination with glutamine targeting agents, chloroquine for lysosomal targeting, hyperbaric oxygen therapy, and calorie restriction. Conclusions: This metabolic approach can be considered as a promising non-toxic strategy for cancer management.


2021 ◽  
Vol 271 ◽  
pp. 03033
Author(s):  
Junxi Mou

Aging is a programmed and spontaneous life course that organisms must undergo, and as an irreversible and relatively conservative process, several theories have tried to explain its causes. Among them, the somatic mutation theory, the free radical theory, the natural cross-linking of biomolecules, the immune theory, the telomere theory, the biological clock theory, and the toxic theory are among the most widely accepted hypotheses. However, no single doctrine can fully explain the aging process. Aging is mainly manifested in the structural and functional aging and decline of organisms, and as organisms continue to age, most organs will experience varying degrees of aging and irreversible damage, although it is directly related to many diseases, aging itself is generally not considered as a disease. Any organism ages slowly over time, with the most easily observable manifestations in external changes such as diminished hair color and sagging skin. Numerous studies have shown that mitochondria are instrumental in mitigating aging as the primary provider of cellular energy, providing energy for cell growth and development as well as being the center of cellular metabolism; therefore, once mitochondria become faulty, a large number of cells will lose function, age, and thus die. In this paper, we will discuss in detail the relationship between mitochondria and aging and how external interventions can promote the function of mitochondria in delaying aging.


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