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The possible role of human placental lactogen in worse outcomes of differentiated thyroid cancer in pregnancy
Lactogens comprise three closely related peptide hormones: human growth hormone (hGH), human placental lactogen (hPL), and human prolactin (hPRL). hPRL and hGH originate from the pituitary and hPL is secreted by syncytiotrophoblasts of the placenta. Levels of hPL vary during pregnancy; it can be detected from the sixth week of gestation, increases steadily in the […]
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A hypothesis on the possible contribution of free hypoxanthine and adenine bases in prebiotic amino acid synthesis
Experimental conditions were devised, imitating prebiotic conditions in hydrothermal vents, to examine the possible prebiotic role of free purine bases in the direct synthesis of amino acids. Hypoxanthine, the biochemical precursor of adenine and guanine, was able to capture nitrite ions and be reductively transformed into adenine. Transfer of the exocyclic group of adenine into uracil […]
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Ionizing radiation – an evolutionary threat?
In the aftermath of the Fukushima nuclear accident, it has often been argued by the concerned public that radioactivity and ionizing radiation have to be considered intrinsically harmful because humans have no sensory organ for this type of radiation. It is not only true that humans lack a sense for ionizing radiation, but no organism […]
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Designing a living mammalian cell
Living cells continue to attract the attention of researchers for understanding their origin, design and function. Recent advances in molecular science, biochemical devices and computational tools have generated renewed interest in unravelling the secret of formation of living cells. It is unclear how primitive life forms originated from non-living molecules. Multi-directional approaches have yielded deeper […]
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Milder forms of obesity may be a good evolutionary adaptation: ‘Fitness First’ hypothesis
The prevalence of obesity is steadily increasing and is considered maladaptive, as it is a risk factor for diabetes, hypertension, cardiovascular illnesses and cancer. However, contrary to popular belief and expectations, recent studies have shown that people with milder grades of adiposity survive better (obesity paradox), both in normal and adverse conditions. Several new observations […]
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RNA evolution conjectured from tRNA and riboswitches
The structures of tRNAs and riboswitches comprise distinct domains. A tRNA molecule is L-shaped, and each arm may reflect its evolution. The amino acid-nonspecific minihelix domain may have emerged before the amino acid-specific anticodon-containing domain was acquired. The glycine riboswitch of Bacillus subtilis functions in a “glycine-independent” manner in the presence of polyethylene glycol or […]
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Does intracrine amplification provide a unifying principle for the progression of common neurodegenerative disorders?
Many extracellular signaling proteins, such as hormones and growth factors, can act within their cells of synthesis or after secretion and internalization by target cells. These factors are called intracrines; aspects of their biology have been defined. The actions of these factors are mirrored in the cell-to-cell transmission of prions and prion-like proteins in common […]
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Hepatocellular carcinoma: Putative interactive mechanism between aflatoxins and hepatitis viral infections implicating oxidative stress during the onset and progression of cancer
The association of hepatocellular carcinoma (HCC) with hepatitis B virus (HBV), hepatitis C virus (HCV) and mycotoxins, especially aflatoxins, has been established. Mycotoxins are commonly encountered by the consumption of mycotoxin-contaminated food by African and Asian populations. A number of mechanisms contribute to the high risk of HCC in individuals with both aflatoxin B1 (AFB1)-DNA […]
