Comparison of Surface Equivalent Dose in CBCT, Digital Panoramic and Intra-Oral X-Ray Generators Using InstadoseTM Device: An In-Vitro Study

Background: Radiation protection in the dental examination is often overlooked because the doses delivered are negligible. However, the volume of dental radiological examinations will constitute almost 15% of all the radiological examinations carried out in the medical field. Aim: This study aims to evaluate and compare the surface equivalent dose on various target organs from various radiology devices on the RINN phantom, and the effect of numerous scanning protocols on said dose using dosimetry badge (Instadose). Objectives: The main objective is to study surface equivalent doses delivered in various critical organ regions in the facial region with the help of an Instadose device and to compare the doses delivered between 2D programs against 3D programs. Materials and Methods: RINN phantom was mounted on a dental chair for use against Planmeca ProMax 3D Classic and Planmeca intraoral ProX. Models. An Instadose badge was placed on various anatomical landmarks, and radiographic exposure protocols were applied to vary the parameters. The equivalent dose was calculated by connecting the dosimeter to a laptop and performing an instant reading output on the Instadose software. Results: The Thyroid showed a mean of 0.350, 0.0000, 0.0133, and 0.0000 in response to exposure by intraoral machine ProX, Panoramic, CBCT, and CBCT in ULD mode respectively. The dose absorbed by the left salivary glands was found to be significantly lower than the right salivary glands in panoramic exposures. Conclusion: It was revealed that a significant reduction in the dose when applying the Ultra-Low Dose protocol was noticed, and it reached up to 100% in the thyroid. It was also noted that there is no need for a thyroid collar in CBCT and Panoramic exposures. Maintaining the KVp at a constant and the exposure time as a variant caused a change in the dose equivalent received by the floor of the mouth and the right salivary gland.

Overview on Neurological Manifestations of Thyroid Disease

Hypothyroidism and hyperthyroidism are both prevalent medical conditions that are frequently accompanied with neurologic and neuromuscular dysfunction. Triiodothyronine (T3) and thyroxine (T4) hormones are produced by the thyroid gland and play a crucial role in tissue formation and metabolism. Both of these hormones have a variety of impacts on the brain and neuromuscular system. Specially in children, because brain development can be effected by any disturbances in Thyroidal hormones level. And thus, conditions like Allan-Herndon-Dudley Syndrome & Benign Hereditary Chorea is considered genetic thyroidal diseases both will be discussed in this review. hypothyroidism can have serious consequences for neuropsychiatric function. The pathophysiological processes underlying the neurological symptoms of hypothyroidism and hyperthyroidism are likely to be multifactorial, in this review we will be looking at multiple neurological as well as psychiatric manifestations related to thyroidal hormones disorders. Methods: We used the phrases "hypothyroidism," "hyperthyroidism," "neurological problems," "neuropathy," "myopathy," "congenital hypothyroidism," and "encephalopathy" in a PubMed search, google scholar and google search engines. Case series, individual case reports, systematic reviews, retrospective analyses, and randomized controlled trials were among the papers examined. Classification of thyroidal dysfunction has been made depending on the thyroidal hormones level. The neurological consequences of congenital hypothyroidism were examined, as well as the clinical aspects of hypothyroidism and hyperthyroidism-related neuromuscular disorders, as well as other autoimmune illnesses. Hashimoto encephalopathy's evidence and pathophysiological issues were also examined. Conclusion: Thyroid is critical organ due to role of its thyroidal hormones, both hypothyroidism and hyperthyroidism induce some serious neurological and phycological disorders, some of which is genetic, hypothyroidism can impact the development of child and thus regular thyroidal hormones testing is recommended in children who demonstrates any signs of neurological psychiatric or cognitive disease.

CYP19A1 mediated sex hormone metabolism promotes severe SARS-CoV-2 disease outcome in males.

Male sex belongs to one of the major risk factors for severe COVID-19 outcome. However, underlying mechanisms that could affect sex dependent disease outcome are yet unknown. Here, we identified the CYP19A1 gene encoding for the testosterone-to-estradiol metabolizing enzyme CYP19A1 (alias aromatase) as a male abundant host factor that contributes to worsened disease outcome in SARS-CoV-2 infected male hamsters. Pulmonary CYP19A1 transcription is further elevated upon viral infection in males correlating with reduced testosterone and increased estradiol levels. Dysregulated circulating sex hormone levels in male golden hamsters are associated with reduced lung function compared to females. Treatment of SARS-CoV-2 infected hamsters with letrozole, a clinically approved CYP19A1 inhibitor, supported recovery of dysregulated plasma sex hormone levels and was associated with improved lung function and health in male but not female animals compared to placebo controls. Whole human exome sequencing data analysis using a Machine Learning approach revealed a CYP19A1 activity increasing mutation being associated with the development of severe COVID-19 for men. In human autopsy-derived lungs CYP19A1 was expressed to higher levels in men who died of COVID-19, at a time point when most viral RNA was cleared. Our findings highlight the role of the lung as a yet unrecognized but critical organ regulating metabolic responses upon respiratory virus infection. Furthermore, inhibition of CYP19A1 by the clinically approved drug letrozole may pose a new therapeutic strategy to reduce poor long-term COVID-19 outcome.

Establishing indicators for assessing non-carcinogenic risks under chronic inhalation expo-sure to benzene and average annual mpc for benzene as per health risk criteria

Recently multiple new toxicological and epidemiologic data on negative effects produced by chemicals have become available; given that, it is necessary to improve quantitative criteria applied in health risk assessment. It is advisable to revise previously established reference concentrations and to make more precise lists of organs and systems affected by a chemical in concentrations which are either equal to reference one or exceed it. Our research aim was to establish a reference concentration for benzene and additional quantitative indicators of its effects (additional reference concentrations) on specific organs and systems under chronic inhalation exposure; another aim was to determine average annual MPC verified as per permissible lifetime carcinogenic risk using evolution models. The research allowed recommending 0.005 mg/m3 to be used as a reference concentration under chronic inhalation exposure to benzene; a decrease in quantity of B-lymphocytes was recommended as a critical effect since this decrease might produce negative effects on the blood and immune system. Additional reference concen-trations for benzene were fixed at 0.007 mg/m3 for the liver as a critical organ and 0.012 mg/mg3 for violated process of organism development as a critical effect. They can be used as additional indicators for assessing non-carcinogenic health risks under chronic inhalation exposure to benzene in its elevated concentrations. Our research results were used to substantiate average annual MPC for benzene in ambient air; its recommended value was 0.005 mg/m3 since it provided safety (absence of impermis-sible (unacceptable) lifetime health risk), probable carcinogenic effects taken into account.

Opinion article: the METREPOL criteria – are they still relevant?

The Medical management of radiation accidents manual on the acute radiation syndrome (METREPOL) proposed a successful strategic approach to diagnosing and treating acute radiation syndrome: the response category concept. Based on clinical and laboratory parameters, this approach aimed to assess damage to critical organ systems as a function of time, categorising different therapeutical approaches. After 20 years of its publication, the following paper attempts to provide a broad overview of this important document and tries to respond if proposed criteria are still relevant for the medical management of radiation-induced injuries. In addition, a critical analysis of its limitations and perspectives is proposed.

Principles of Researching Health Disparities in Longitudinal Cohort Studies Enrolling Children

Health disparities are defined on the basis of specific populations that, when compared to the general population, have a significant disparity on the rate of disease incidence, prevalence, morbidity, mortality, or survival. People that experience health disparities can be defined by multiple criteria. As the diversity of the United States broadens and increases, research on the origins and causes of health disparities becomes more important to support a healthy general population. Children are particularly sensitive to and vulnerable to health disparities due to the potentially life long consequences of events during periods of critical organ, intellectual and social development. The concept of health justice whereby each individual has the opportunity to realize their full health potential can only be realized with proper understanding and relevant data to frame practice, policy and actions. The National Children's Study (NCS) was a longitudinal birth cohort study designed to incorporate the principles of the Federal Collaboration on Health Disparities Research in consultation with subject matter experts, community representatives, and ongoing evaluation to ensure high quality and relevant data on factors that impact health outcomes. The NCS developed and tested a model of enrolling a diverse population, capturing and integrating data using a life course framework, constructing individual profiles, then aggregating individuals into groups based on profiles and outcomes. This approach is applicable to other longitudinal cohort studies.

The Thyroid – a New Critical Body for Impacting Electromagnetic Fields Mobile Communications: Assessment of Possible Effects for Children and Adolescents

This publication provides an analysis of the studies of Russian and foreign scientists dealing with the problem of studying the effect of electromagnetic fields on the state of the thyroid gland as a new critical organ directly experiencing this type of exposure when using a new generation of mobile communications – smartphones. The review includes an introduction, five sections, and a conclusion. In the section “Distribution of absorbed doses when using mobile phones” studies of the distribution and level of absorption of electromagnetic fields when using mobile communications, including the thyroid gland, are presented. The issues of modelling taking into account the size of the head and the properties of the tissues of children are discussed. “Epidemiological and statistical assessments of thyroid dysfunction” – this section summarizes the data on the incidence of the thyroid gland among the child population in Russia for the period 1990 – 2019. The section “Experimental studies” presents the experimental data of domestic and foreign scientists on morphological and hormonal changes in the thyroid gland of experimental animals when exposed to electromagnetic fields of cellular communication. Biomedical studies of the effects of their impact are described in the section “Changes in the functioning of the thyroid gland in mobile users”. The review is completed by the section “Possible long-term consequences of prolonged exposure to electromagnetic fields on the thyroid gland in mobile communication users”.

Role of hippocampal location and radiation dose in glioblastoma patients with hippocampal atrophy

Background The hippocampus is a critical organ for irradiation. Thus, we explored changes in hippocampal volume according to the dose delivered and the location relative to the glioblastoma. Methods All patients were treated for glioblastoma with surgery, concomitant radiotherapy and temozolomide, and adjuvant temozolomide. Hippocampi were retrospectively delineated on three MRIs, performed at baseline, at the time of relapse, and on the last MRI available at the end of follow-up. A total of 98, 96, and 82 hippocampi were measured in the 49 patients included in the study, respectively. The patients were stratified into three subgroups according to the dose delivered to 40% of the hippocampus. In the group 1 (n = 6), the hippocampal D40% was < 7.4 Gy, in the group 2 (n = 13), only the Hcontra D40% was < 7.4 Gy, and in the group 3 (n = 30), the D40% for both hippocampi was > 7.4 Gy. Results Regardless of the time of measurement, homolateral hippocampal volumes were significantly lower than those contralateral to the tumor. Regardless of the side, the volumes at the last MRI were significantly lower than those measured at baseline. There was a significant correlation among the decrease in hippocampal volume regardless of its side, and Dmax (p = 0.001), D98% (p = 0.028) and D40% (p = 0.0002). After adjustment for the time of MRI, these correlations remained significant. According to the D40% and volume at MRIlast, the hippocampi decreased by 4 mm3/Gy overall. Conclusions There was a significant relationship between the radiotherapy dose and decrease in hippocampal volume. However, at the lowest doses, the hippocampi seem to exhibit an adaptive increase in their volume, which could indicate a plasticity effect. Consequently, shielding at least one hippocampus by delivering the lowest possible dose is recommended so that cognitive function can be preserved. Trial registration Retrospectively registered.