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1.
J Biomed Phys Eng ; 12(5): 539-542, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36313404

RESUMEN

An accumulating body of evidence shows that various ethnicities are differentially affected by SARS-COV-2 infection. Moreover, some evidence shows that due to the vaccine inequity and millions of people living with HIV, a major catastrophe could occur in African countries that possibly affects the whole world. Given the possibility that Neanderthal genes confer a slight increase in susceptibility, this difference, at least to some extent, might possibly decrease the risk of the emergence of new SARS-CoV-2 variants among black people in Africa. Recent studies show less death and fewer cases among the ethnic group classified as "Black Africans". Although Neanderthal DNA might explain some differences in morbidity and mortality of COVID-19, a multitude of confounders complicate things to where drawing definite conclusions is hard or even impossible. Using selective-pressure-free treatments (e.g. low dose radiotherapy) for COVID-19 pneumonia would be of crucial importance everywhere, but particularly in sub-Saharan Africa, where "long COVID" in millions of people with HIV paves the road for the more frequent emergence of new variants.

2.
J Biomed Phys Eng ; 12(5): 535-538, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36313407

RESUMEN

The Omicron variant is spreading at a rate we have never observed with any previous variant. A lot of efforts have been taken to inactivate SARS-CoV-2, especially the omicron variant. Specific wavelength ranges of electromagnetic radiation can be exploited to inactivate coronaviruses. Previous studies show that 222-nm far-Ultraviolet C (far-UVC) light inactivates airborne influenza virus efficiently. Considering the similar genomic sizes of all human coronaviruses, other human coronaviruses, such as SARS-CoV-2, would be expected to be inactivated by far-UVC with a similar efficacy. Taking this into account, it is concluded that exposure to far-UVC can be introduced as a safe method that significantly reduces the ambient level of airborne coronaviruses in crowded places. Biomolecules, particularly proteins, strongly absorb ultraviolet radiation at a wavelength of around 200 nm. Given this consideration, far-UVC has a limited ability to permeate biological materials. Thus, for example, in only around 0.3 mm of tissue, the intensity of 200-nm UV radiation is decreased by half, compared to tissue penetration of about 3 mm at 250 nm. This paper aims to answer the key question of whether far-UVC can penetrate SARS-CoV-2 inside inhalable respiratory droplets (with diameters up to 100 µm).

3.
J Biomed Phys Eng ; 12(2): 211-212, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35433524

RESUMEN

It has previously been reported that differences in life expectancy can be linked to income. In Norway, a registry-based study that included all Norwegian residents aged ≥ 40 years (2005-2015) was performed. This study showed substantial and increasing gaps in life expectancy by income level during the interval between 2005-2015. Compared to the United States, the largest life expectancy differences were for individuals in the lower to middle part of the income distribution, although differences were observed at all income levels. Despite its undeniable strengths and although this paper can be considered as a significant contribution to this field, it has some shortcomings. The first shortcoming of this study is due to ignoring the effects of population exposures to natural and man-made ionizing and non-ionizing radiation on life expectancy. Another shortcoming arises from ignoring the strong impact of education on lifestyle. In summary, what is observed in this study might be at least to some extent, due to education-related changes in lifestyle and not necessarily income (despite the mutual links between education and income).

4.
Dose Response ; 20(1): 15593258221075111, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35392263

RESUMEN

Despite current controversies, some reports show a paradoxical mitigating effect associated with smoking in individuals with symptomatic COVID-19 compared to the general population. To explain the potential mechanisms behind the lower number of hospitalized COVID-19 patients, it has been hypothesized that cigarette smoking may reduce the odds of cytokine storm and related severe inflammatory responses through cholinergic-mediated anti-inflammatory mechanisms. Japanese scientists have recently identified a potential mechanism behind the lower numbers of COVID-19 cases amongst smokers compared to non-smokers. However, we believe that this mitigative effect may be due to the relatively high concentration of deposited energy of alpha particles emitted from naturally occurring radionuclides such as Po-210 in cigarette tobacco. Regarding COVID-19, other researchers and our team have previously addressed the anti-inflammatory and immune-modulating effects of low doses of ionizing radiation. MC-simulation using the Geant4 Monte Carlo toolkit shows that the radiation dose absorbed in a spherical cell with a radius of .9 µm for a single 5.5 MeV alpha particle is about 5.1 Gy. This energy deposition may trigger both anti-inflammatory and anti-thrombotic effects which paradoxically lower the risk of hospitalization due to COVID-19 in smokers.

5.
Health Phys ; 122(4): 508-512, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35244616

RESUMEN

ABSTRACT: Terrestrial experiments involving acute exposures of low-LET radiation on inbred lab animals are quick, simple, and inexpensive but are relatively uninformative about the real radiobiological hazards of planned manned space missions. A more predictive model could involve human beings chronically exposed to "space-like" high-LET radiation. Such radiation exposure has been ongoing for thousands of years in Ramsar, Iran, and some other high-LET high background radiation regions on Earth. Examining the health of Ramsar residents can be illuminating and potentially relevant to space missions.


Asunto(s)
Marte , Exposición a la Radiación , Vuelo Espacial , Animales , Irán , Radiobiología
7.
12.
Dose Response ; 18(3): 1559325820950104, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32868978

RESUMEN

The primum non nocere letter by Boon et al. urged caution and careful examination of the evidence and logistics of low-dose radiotherapy in COVID-19 patients. This is exactly what was requested in March and what has occurred since late April 2020 when the first phase I/II clinical trial was approved at the Winship Cancer Institute, Emory University Hospital. The preprint of day-7 interim results by the investigators concluded, "In a small pilot trial of 5 oxygen-dependent patients with COVID-19 pneumonia, low-dose whole-lung radiation led to rapid improvement in clinical status, encephalopathy, and radiographic infiltrates without acute toxicity or worsening the cytokine storm. Low-dose whole-lung radiation appears to be safe, shows early promise of efficacy, and warrants larger prospective trials." Preliminary results from another clinical trial gave similar results. In conclusion, the authors believe it would be unethical not to investigate radiotherapy as a potential remedy against COVID-19 induced pneumonia.

14.
Cells ; 9(7)2020 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-32708131

RESUMEN

This letter addresses our concerns about a paper by Melnik et al [...].


Asunto(s)
Neoplasias de la Tiroides , Ingravidez , Línea Celular Tumoral , Dexametasona , Humanos , Esferoides Celulares
17.
eNeuro ; 7(1)2020.
Artículo en Inglés | MEDLINE | ID: mdl-31857344

RESUMEN

Evaluations of the biological effects of space radiation must carefully consider the biological system response and the specific nature of the source term. Acharya et al. (2019) review neurocognitive function during deep space exposures to chronic, low dose rate, neutron radiation, but do not use a source term that reflects the actual space environment in terms of radiation types and their respective energies. In addition, important biological effects, including the adaptive response to the space radiation environment, are not addressed.


Asunto(s)
Neutrones
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