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1.
Adv Genet ; 106: 45-60, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33081925

RESUMEN

The theory of cometary panspermia argues that life cannot have originated on Earth in the time available. It must have an ultimate, but still undiscovered cosmological source. The origin of life remains an open question. Life on Earth was introduced by impacting comets, and its further evolution was driven by the subsequent acquisition of cosmically derived genes. Explicit predictions of this theory stating how the acquisition of new genes drives evolution, are compared with recent developments in relation to horizontal gene transfer, and the role of retroviruses in evolution. Precisely stated predictions of the theory of cometary panspermia are shown to have been verified.


Asunto(s)
ADN/genética , Proteínas/genética , ARN/genética , Animales , Evolución Biológica , Planeta Tierra , Transferencia de Gen Horizontal/genética , Humanos , Retroviridae/genética , Sociología
2.
Adv Genet ; 106: 21-43, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33081924

RESUMEN

In this Chapter we discuss the various mechanisms that are available for the possible transfer of cosmic microbial living systems from one cosmic habitat to another. With the 100 or so habitable planets that are now known to exist in our galaxy alone transfers of cometary dust carrying life including fragments of icy planetoids/asteroids would be expected to occur on a routine basis. It is thus easy to view the galaxy as a single connected "biosphere" of which our planet Earth is a minor component. The Hoyle-Wickramasinghe Panspermia paradigm provides a cogent biological rationale for the actual widespread existence of Lamarckian modes of inheritance in terrestrial systems (which we review here). Thus the Panspermia paradigm provides the raison d'etre for Lamarckian Inheritance. Under a terrestrially confined neoDarwinian viewpoint such an association may have been thought spurious in the past. Our aim here is to outline the main evidence for rapid terrestrial-based Lamarckian-based evolutionary hypermutation processes dependent on reverse transcription-coupled mechanisms among others. Such rapid adaptation mechanisms would be consistent with the effective cosmic spread of living systems. For example, a viable, or cryo-preserved, living system traveling through space in a protective matrix will of necessity need to adapt rapidly and proliferate on landing in a new cosmic niche. Lamarckian mechanisms thus come to the fore and supersede the slow (blind and random) genetic processes expected under neoDarwinian Earth centred theories.


Asunto(s)
Origen de la Vida , Animales , Evolución Biológica , Ecosistema , Galaxias , Humanos , Microbiota , Planetas , Transcripción Reversa/genética
3.
Adv Genet ; 106: 133-143, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33081923

RESUMEN

A wide range of evidence for pointing to our cosmic origins is close to the point of being overwhelming. Yet the long-entrenched paradigm of Earth-centered biology appears to prevail in scientific culture. A matter of crucial importance is to carry out a decisive experiment that is long overdue-establishing empirically beyond any doubt that extraterrestrial microbiota reaches the surface of the Earth at the present day. Such an experiment may of course happen naturally by the appearance of pandemics of new disease as discussed in an earlier chapter.


Asunto(s)
Microbiota/genética , Origen de la Vida , Planeta Tierra , Medio Ambiente Extraterrestre
4.
Adv Genet ; 106: 75-100, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33081928

RESUMEN

The origins and global spread of two recent, yet quite different, pandemic diseases is discussed and reviewed in depth: Candida auris, a eukaryotic fungal disease, and COVID-19 (SARS-CoV-2), a positive strand RNA viral respiratory disease. Both these diseases display highly distinctive patterns of sudden emergence and global spread, which are not easy to understand by conventional epidemiological analysis based on simple infection-driven human- to-human spread of an infectious disease (assumed to jump suddenly and thus genetically, from an animal reservoir). Both these enigmatic diseases make sense however under a Panspermia in-fall model and the evidence consistent with such a model is critically reviewed.


Asunto(s)
Evolución Biológica , Candidiasis/etiología , Enfermedades Transmisibles Emergentes/etiología , Infecciones por Coronavirus/etiología , Origen de la Vida , Neumonía Viral/etiología , Animales , Betacoronavirus/aislamiento & purificación , Betacoronavirus/fisiología , COVID-19 , Candida/aislamiento & purificación , Candida/fisiología , Candidiasis/epidemiología , Enfermedades Transmisibles Emergentes/epidemiología , Coronavirus/aislamiento & purificación , Coronavirus/fisiología , Infecciones por Coronavirus/epidemiología , Planeta Tierra , Exobiología , Medio Ambiente Extraterrestre , Interacciones Huésped-Patógeno/fisiología , Humanos , Pandemias , Neumonía Viral/epidemiología , SARS-CoV-2
5.
Prog Biophys Mol Biol ; 149: 10-32, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31445944

RESUMEN

We review the main lines of evidence (molecular, cellular and whole organism) published since the 1970s demonstrating Lamarckian Inheritance in animals, plants and microorganisms viz. the transgenerational inheritance of environmentally-induced acquired characteristics. The studies in animals demonstrate the genetic permeability of the soma-germline Weismann Barrier. The widespread nature of environmentally-directed inheritance phenomena reviewed here contradicts a key pillar of neo-Darwinism which affirms the rigidity of the Weismann Barrier. These developments suggest that neo-Darwinian evolutionary theory is in need of significant revision. We argue that Lamarckian inheritance strategies involving environmentally-induced rapid directional genetic adaptations make biological sense in the context of cosmic Panspermia allowing the efficient spread of living systems and genetic innovation throughout the Universe. The Hoyle-Wickramasinghe Panspermia paradigm also developed since the 1970s, unlike strictly geocentric neo-Darwinism provides a cogent biological rationale for the actual widespread existence of Lamarckian modes of inheritance - it provides its raison d'être. Under a terrestrially confined neo-Darwinian viewpoint such an association may have been thought spurious in the past. Our aim is to outline the conceptual links between rapid Lamarckian-based evolutionary hypermutation processes dependent on reverse transcription-coupled mechanisms among others and the effective cosmic spread of living systems. For example, a viable, or cryo-preserved, living system travelling through space in a protective matrix will need of necessity to rapidly adapt and proliferate on landing in a new cosmic niche. Lamarckian mechanisms thus come to the fore and supersede the slow (blind and random) genetic processes expected under a traditional neo-Darwinian evolutionary paradigm.


Asunto(s)
Evolución Biológica , Origen de la Vida , Animales , Bacterias/genética , Secuencia de Bases , Progresión de la Enfermedad , Epigénesis Genética , Femenino , Interacción Gen-Ambiente , Genoma , Humanos , Masculino , Mutagénesis , Neoplasias/genética , Plantas/genética , Selección Genética
6.
Prog Biophys Mol Biol ; 136: 3-23, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29544820

RESUMEN

We review the salient evidence consistent with or predicted by the Hoyle-Wickramasinghe (H-W) thesis of Cometary (Cosmic) Biology. Much of this physical and biological evidence is multifactorial. One particular focus are the recent studies which date the emergence of the complex retroviruses of vertebrate lines at or just before the Cambrian Explosion of ∼500 Ma. Such viruses are known to be plausibly associated with major evolutionary genomic processes. We believe this coincidence is not fortuitous but is consistent with a key prediction of H-W theory whereby major extinction-diversification evolutionary boundaries coincide with virus-bearing cometary-bolide bombardment events. A second focus is the remarkable evolution of intelligent complexity (Cephalopods) culminating in the emergence of the Octopus. A third focus concerns the micro-organism fossil evidence contained within meteorites as well as the detection in the upper atmosphere of apparent incoming life-bearing particles from space. In our view the totality of the multifactorial data and critical analyses assembled by Fred Hoyle, Chandra Wickramasinghe and their many colleagues since the 1960s leads to a very plausible conclusion - life may have been seeded here on Earth by life-bearing comets as soon as conditions on Earth allowed it to flourish (about or just before 4.1 Billion years ago); and living organisms such as space-resistant and space-hardy bacteria, viruses, more complex eukaryotic cells, fertilised ova and seeds have been continuously delivered ever since to Earth so being one important driver of further terrestrial evolution which has resulted in considerable genetic diversity and which has led to the emergence of mankind.


Asunto(s)
Fenómenos Astronómicos , Origen de la Vida , Animales , Evolución Biológica , Retroviridae/fisiología
9.
Int J Antimicrob Agents ; 35(1): 56-61, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19910163

RESUMEN

Amoebiasis, caused by infection with the enteric protist Entamoeba histolytica, is one of the major parasitic diseases. Although metronidazole and its derivatives are currently employed in therapy, the paucity of effective drugs and potential clinical resistance necessitate the development of a novel drug. Trifluoromethionine (TFM) is a promising lead compound for antiamoebic drugs. To potentiate the antiamoebic effect of TFM, we synthesised various amide derivatives of TFM and evaluated their cytotoxicity. The amide derivatives of TFM were observed to have a superior cytotoxic effect compared with TFM and metronidazole against E. histolytica in vitro. Although TFM showed cytotoxicity following degradation by methionine gamma-lyase, the derivatives were degraded by the enzyme less efficiently compared with TFM. We further demonstrated that a representative derivative was hydrolysed by the amoebic cell lysate to first yield TFM, followed by degradation similar to TFM. Hydrolysis was partially inhibited by protease inhibitors. A single subcutaneous or oral administration of TFM and its amide derivatives also effectively prevented the formation of amoebic liver abscess in a rodent model. These data demonstrate the improved effectiveness of TFM derivatives against E. histolytica infection and elucidate the mechanisms underlining the mode of action of these compounds.


Asunto(s)
Amidas/farmacología , Amidas/uso terapéutico , Antiprotozoarios/farmacología , Antiprotozoarios/uso terapéutico , Entamoeba histolytica/efectos de los fármacos , Metionina/análogos & derivados , Administración Oral , Amidas/administración & dosificación , Amidas/química , Animales , Antiprotozoarios/administración & dosificación , Antiprotozoarios/química , Cricetinae , Cricetulus , Entamebiasis/tratamiento farmacológico , Concentración 50 Inhibidora , Absceso Hepático/prevención & control , Metionina/administración & dosificación , Metionina/química , Metionina/farmacología , Metionina/uso terapéutico , Metronidazol/farmacología , Estructura Molecular , Relación Estructura-Actividad Cuantitativa
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