Differential Functional Changes in Visual Performance during Acute Exposure to Microgravity Analogue and Their Potential Links with Spaceflight-Associated Neuro-Ocular Syndrome.

BACKGROUND: Spaceflight-Associated Neuro-Ocular Syndrome (SANS) is a complex pathology threatening the health of astronauts, with incompletely understood causes and no current specific functional diagnostic or screening test. We investigated the use of the differential performance of the visual system (central vs. perimacular visual function) as a candidate marker of SANS-related pathology in a ground-based microgravity analogue. METHODS: We used a simple reaction time (SRT) task to visual stimuli, presented in the central and perimacular field of view, as a measure of the overall performance of the visual function, during acute settings (first 10 min) of vertical, bed rest (BR), -6°, and -15° head-down tilt (HDT) presentations in healthy participants (n = 8). We built dose-response models linking the gravitational component to SRT distribution parameters in the central vs. perimacular areas. RESULTS: Acute exposure to microgravity induces detectable changes between SRT distributions in the perimacular vs. central retina (increased mean, standard deviation, and tau component of the ex-Gaussian function) in HDT compared with vertical presentation. CONCLUSIONS: Functional testing of the perimacular retina might be beneficial for the earlier detection of SANS-related ailments in addition to regular testing of the central vision. Future diagnostic tests should consider the investigation of the extra-macular areas, particularly towards the optic disc.

Caregiving for Dementia Patients during the Coronavirus Pandemic.

The coronavirus pandemic has had a global impact on both mental and physical health. Caregiving has become more difficult during this time due to the quick spread of this respiratory disease, dread of the unknown, congested hospitals, and many restrictions, particularly for people with multiple comorbidities. We aimed to assess the impact of this pandemic on a group of caregivers of patients with dementia and their needs during this time. The study's findings indicate that females assumed the role of the caregiver more often than men (88.5% of the participants) and scored lower on the life quality scale. The most often issue encountered during the pandemic was difficulty in accessing health care facilities (36%). Participants with a higher education level scored better in the physical (24.67, p = 0.01 and 24.48, p = 0.01) and mental health (20.67, p = 0.002; 19,82, p = 0.008) domains of the life quality test. The fear of COVID questionnaire showed a low level of concern in the category of participants with a high education level. Overall, this pandemic emphasizes the importance of social interaction and the possibilities to improve health care services through telemedicine. Caregivers could benefit from socialization and support programs as well as the early detection of affective disorders.

A Comparison of 13C-Methacetin and 13C-Octanoate Breath Test for the Evaluation of Nonalcoholic Steatohepatitis.

BACKGROUND: While non-alcoholic fatty liver disease (NAFLD) is a wide-spread liver disease, only some patients progress towards steatohepatitis and cirrhosis. AIM: We comparatively analyzed the methacetin breath test (MBT) for the microsomal function of the liver and the octanoate breath test (OBT) for mitochondrial activity, in detecting patients with steatohepatitis and estimating fibrosis. METHODS: 81 patients with histologically proven NAFLD (SAF score) were evaluated. The parameters used for both breath tests were the dose/h and the cumulative dose recovery at multiple timepoints. The statistical association between histological diagnosis and breath test results used Independent Samples t Test. The accuracy for diagnosis was evaluated using area under the receiver operator characteristic (AUROC) and the sensitivity and specificity were assessed using the Youden J method. RESULTS: Both MBT and OBT were able to differentiate patients with simple steatosis from NASH and to stratify patients with significant fibrosis and cirrhosis (p-values < 0.001 for most analyzed timepoints). The best parameter for NASH diagnosis was OBT dose at 30 min. In the case of significant fibrosis, the most accurate test was MBT cumulative dose at 30 min. CONCLUSIONS: Both MBR and OBT tests are potentially useful tools in assessing patients with NAFLD.

Striated Muscle Evaluation Based on Velocity and Amortization Ratio of Mechanical Impulse Propagation in Simulated Microgravity Environment.

Long-duration space flight missions impose extreme physiological stress and/or changes, such as musculoskeletal function degradation, on the crew due to the microgravity exposure. A great deal of research studies have been conducted in order to understand these physiological stress influences and to provide countermeasures to minimize the observed negative effects of weightlessness exposure on musculoskeletal function. Among others, studies and experiments have been conducted in DI analogue Earth-based facilities in order to reproduce the weightlessness negative effects on the human body. This paper presents a complex muscular analysis of mechanical wave propagation in striated muscle, using MusTone, a device developed in-house at the Institute of Space Science, Romania. The data were collected during a 21-day DI campaign in order to investigate muscle fibers' behavior in longitudinal direction, after applying a mechanical impulse, taking into account two particular parameters, namely propagation velocity and amortization ratio. The parameters were determined based on the wave-propagation data collected from five points (one impact point, two distal direction points, and two proximal direction points) along the muscle fiber. By statistically analyzing propagation velocity and amortization ratio parameters, the study revealed that muscle deconditioning is time dependent, the amortization ratio is more significant in the distal direction, and the lower fibers are affected the most.

New O-Aryl-Carbamoyl-Oxymino-Fluorene Derivatives with MI-Crobicidal and Antibiofilm Activity Enhanced by Combination with Iron Oxide Nanoparticles.

Antimicrobial resistance is one of the major public health threats at the global level, urging the search for new antimicrobial molecules. The fluorene nucleus is a component of different bioactive compounds, exhibiting diverse pharmacological actions. The present work describes the synthesis, chemical structure elucidation, and bioactivity of new O-aryl-carbamoyl-oxymino-fluorene derivatives and the contribution of iron oxide nanoparticles to enhance the desired biological activity. The antimicrobial activity assessed against three bacterial and fungal strains, in suspension and biofilm growth state, using a quantitative assay, revealed that the nature of substituents on the aryl moiety are determinant for both the spectrum and intensity of the inhibitory effect. The electron-withdrawing inductive effect of chlorine atoms enhanced the activity against planktonic and adhered Staphylococcus aureus, while the +I effect of the methyl group enhanced the anti-fungal activity against Candida albicans strain. The magnetite nanoparticles have substantially improved the antimicrobial activity of the new compounds against planktonic microorganisms. The obtained compounds, as well as the magnetic core@shell nanostructures loaded with these compounds have a promising potential for the development of novel antimicrobial strategies.

Non-invasive laboratory, imaging and elastography markers in predicting varices with high risk of bleeding in cirrhotic patients.

Introduction. Upper digestive tract endoscopy remains the gold-standard for detecting esophageal or gastric varices and assessment of bleeding risk, but this method is invasive. The aim of the study was to identify non-invasive factors that could be incorporated into an algorithm for estimating the risk of variceal bleeding.Methods. A prospective study was performed on 130 cirrhotic patients. Tests were performed on all patients which included liver enzymes, complete blood count and coagulation parameters, abdominal ultrasound, elastography of both the liver and the spleen. Upper gastrointestinal endoscopy was performed in all patients included in the study and the results were classified, in accordance with Baveno VI into 2 outcome groups: Group 1 - patients with low bleeding risk and Group 2 - patients with varices needing treatment.Results. The study lot (130 patients) was divided into: Group I (low bleeding risk - 102 patients), and Group II (high bleeding risk - 28 patients). Parameters found to have significant differences in univariate analysis were transaminases, platelet count, spleen size, INR, portal vein diameter and both liver and spleen elastography. Calculating AUROC for each parameter identifies spleen elastography as having the best result, followed by INR, AST and platelet count. Liver elastography had the worst AUROC. Independent variables identified by logistic regression included spleen elastography, INR, platelet count, spleen diameter, ALT, age, and gender.Conclusions. Spleen stiffness is the best single parameter predicting the presence of high-risk esophageal varices.