Measurement of indoor radioactivity and dose derived from 222Rn, 220Rn and EECs by using SSNTD based technique.

Alpha flux radiated from 222Rn, 220Rn and progeny is the primary contributor of natural radioactivity to the inhabitants in the ambient atmosphere. The annual indoor 222Rn and 220Rn concentrations were found to be 85 ± 43 and 84 ± 36 Bq m-3, respectively. The estimated annual indoor 222Rn and 220Rn concentration is below to reference value of 100 Bq m-3 suggested by WHO. The calculated annual inhalation dose due to exposure to the alpha flux of 222Rn, 220Rn and their progeny is well below the recommended reference level given by UNSCEAR and ICRP. The data were further checked for normalisation and found that 222Rn and Effective Equilibrium Radon Concentration (EERC) data are not normally distributed.

Long term measurements of aerosol mass concentration with optical particle counters: Discrepancies with plausible reasons.

Gravimetry-based direct measurements of mass concentration require offline analysis which is not suited for field campaigns. Hence such campaigns rely on the estimation of mass concentration by indirect methods mostly calibrated in controlled laboratory conditions. Optical particle counter (OPC) employs algorithms converting the measured number concentration to mass concentration using appropriate conversion factors. The accuracy of such conversion has not been validated for widely varying atmospheric conditions. This study compares the mass concentration estimated by OPC with those directly obtained from gravimetry-based instruments for outdoor samples collected in Bathinda City, Punjab, India from January 2022 to November 2023. The difference in the gravimetrically measured and OPC predicted values quantified in terms of ratios (gravimetric to optically estimated mass concentration), came out to be 1.42 ± 0.77, 0.99 ± 0.51, and 1.17 ± 0.58 for PM10, PM2.5 and PM1, respectively. This difference when estimated with the back-up filter of OPC itself (C Factor), was 1.37 ± 0.66. More than half of the samples showed ratios outside the 0.8-1.2 range thus indicating under or over-estimation in the OPC predicted values. The probable role of variation in density, shape, and refractive index of atmospheric aerosol particles towards the observed inaccuracy of estimated mass concentration has been highlighted. In the absence of clear guidelines and protocols, the study suggests ways to improve the accuracy via periodic measurement of the C Factor and/or incorporating calibration factors in such measurements.

G0-PCC-FISH derived multi-parametric biodosimetry methodology for accidental high dose and partial body exposures.

High dose radiation exposures are rare. However, medical management of such incidents is crucial due to mortality and tissue injury risks. Rapid radiation biodosimetry of high dose accidental exposures is highly challenging, considering that they usually involve non uniform fields leading to partial body exposures. The gold standard, dicentric assay and other conventional methods have limited application in such scenarios. As an alternative, we propose Premature Chromosome Condensation combined with Fluorescent In-situ Hybridization (G0-PCC-FISH) as a promising tool for partial body exposure biodosimetry. In the present study, partial body exposures were simulated ex-vivo by mixing of uniformly exposed blood with unexposed blood in varying proportions. After G0-PCC-FISH, Dolphin's approach with background correction was used to provide partial body exposure dose estimates and these were compared with those obtained from conventional dicentric assay and G0-PCC-Fragment assay (conventional G0-PCC). Dispersion analysis of aberrations from partial body exposures was carried out and compared with that of whole-body exposures. The latter was inferred from a multi-donor, wide dose range calibration curve, a-priori established for whole-body exposures. With the dispersion analysis, novel multi-parametric methodology for discerning the partial body exposure from whole body exposure and accurate dose estimation has been formulated and elucidated with the help of an example. Dose and proportion dependent reduction in sensitivity and dose estimation accuracy was observed for Dicentric assay, but not in the two PCC methods. G0-PCC-FISH was found to be most accurate for the dose estimation. G0-PCC-FISH has potential to overcome the shortcomings of current available methods and can provide rapid, accurate dose estimation of partial body and high dose accidental exposures. Biological dose estimation can be useful to predict progression of disease manifestation and can help in pre-planning of appropriate & timely medical intervention.

How Do Quantitative Tissue Imaging Outcomes in Acute Ischemic Stroke Relate to Clinical Outcomes?

BACKGROUND AND PURPOSE: Infarct volume and other imaging markers are increasingly used as surrogate measures for clinical outcome in acute ischemic stroke research, but how improvements in these imaging surrogates translate into better clinical outcomes is currently unclear. We investigated how changes in infarct volume at 24 hours alter the probability of achieving good clinical outcome (modified Rankin Scale [mRS] 0-2). METHODS: Data are from endovascular thrombectomy patients from the randomized controlled ESCAPE-NA1 (Efficacy and Safety of Nerinetide for the Treatment of Acute Ischaemic Stroke) trial. Infarct volume at 24 hours was manually segmented on non-contrast computed tomography or diffusion-weighted magnetic resonance imaging. Probabilities of achieving good outcome based on infarct volume were obtained from a multivariable logistic regression model. The probability of good outcome was plotted against infarct volume using linear spline regression. RESULTS: A total of 1,099 patients were included in the analysis (median final infarct volume 24.9 mL [interquartile range: 6.6-92.2]). The relationship between total infarct volume and good outcome probability was nearly linear for infarct volumes between 0 mL and 250 mL. In this range, a 10% increase in the probability of achieving mRS 0-2 required a decrease in infarct volume of approximately 34.0 mL (95% confidence interval: -32.5 to -35.6). At infarct volumes above 250 mL, the probability of achieving mRS 0-2 probability was near zero. The relationships of tissue-specific infarct volumes and parenchymal hemorrhage volume generally showed similar patterns, although variability was high. CONCLUSION: There seems to be a near-linear association between total infarct volume and probability of achieving good outcome for infarcts up to 250 mL, whereas patients with infarct volumes greater than 250 mL are highly unlikely to have a favorable outcome.

Influence of Infarct Morphology and Patterns on Cognitive Outcomes After Endovascular Thrombectomy.

BACKGROUND: To assess the association of qualitative and quantitative infarct characteristics and 3 cognitive outcome tests, namely the Montreal Cognitive Assessment (MOCA) for mild cognitive impairment, the Boston Naming Test for visual confrontation naming, and the Sunnybrook Neglect Assessment Procedure for neglect, in large vessel occlusion stroke. METHODS: Secondary observational cohort study using data from the randomized-controlled ESCAPE-NA1 trial (Safety and Efficacy of Nerinetide in Subjects Undergoing Endovascular Thrombectomy for Stroke), in which patients with large vessel occlusion undergoing endovascular treatment were randomized to receive either intravenous Nerinetide or placebo. MOCA, Sunnybrook Neglect Assessment Procedure, and 15-item Boston Naming Test were obtained at 90 days. Total infarct volume, gray matter, and white matter infarct volumes were manually measured on 24-hour follow-up imaging. Infarcts were also visually classified as either involving the gray matter only or both the gray and white matter and scattered versus territorial. Associations of infarct variables and cognitive outcomes were analyzed using multivariable ordinal or binary logistic regression models. RESULTS: Of 1105 patients enrolled in ESCAPE-NA1, 1026 patients with visible infarcts on 24-hour follow-up imaging were included. MOCA and Sunnybrook Neglect Assessment Procedure were available for 706 (68.8%) patients and the 15-item Boston Naming Test was available for 682 (66.5%) patients. Total infarct volume was associated with worse MOCA scores (adjusted common odds ratio per 10 mL increase, 1.05 [95% CI, 1.04-1.06]). After adjusting for baseline variables and total infarct volume, mixed gray and white matter involvement (versus gray matter-only adjusted common odds ratio, 1.92 [95% CI, 1.37-2.69]), white matter infarct volume (adjusted common odds ratio per 10 mL increase 1.36 [95% CI, 1.18-1.58]) and territorial (versus scattered) infarct pattern (adjusted common odds ratio, 1.65 [95% CI, 1.15-2.38]) were associated with worse MOCA scores. Results for Sunnybrook Neglect Assessment Procedure and 15-item Boston Naming Test were similar, except for the territorial infarct pattern, which did not reach statistical significance in multivariable analysis. CONCLUSIONS: Besides total infarct volume, infarcts that involve the white matter and that show a territorial distribution were associated with worse cognitive outcomes, even after adjusting for total infarct volume.

Marine cyanobacterial biomass is an efficient feedstock for fungal bioprocesses.

BACKGROUND: Marine cyanobacteria offer many sustainability advantages, such as the ability to fix atmospheric CO2, very fast growth and no dependence on freshwater for culture. Cyanobacterial biomass is a rich source of sugars and proteins, two essential nutrients for culturing any heterotroph. However, no previous study has evaluated their application as a feedstock for fungal bioprocesses. RESULTS: In this work, we cultured the marine cyanobacterium Synechococcus sp. PCC 7002 in a 3-L externally illuminated bioreactor with working volume of 2 L with a biomass productivity of ~ 0.8 g L-1 day-1. Hydrolysis of the biomass with acids released proteins and hydrolyzed glycogen while hydrolysis of the biomass with base released only proteins but did not hydrolyze glycogen. Among the different acids tested, treatment with HNO3 led to the highest release of proteins and glucose. Cyanobacterial biomass hydrolysate (CBH) prepared in HNO3 was used as a medium to produce cellulase enzyme by the Penicillium funiculosum OAO3 strain while CBH prepared in HCl and treated with charcoal was used as a medium for citric acid by Aspergillus tubingensis. Approximately 50% higher titers of both products were obtained compared to traditional media. CONCLUSIONS: These results show that the hydrolysate of marine cyanobacteria is an effective source of nutrients/proteins for fungal bioprocesses.

COVID-19 Antibody Testing in Healthcare Workers in Arkansas.

Introduction Seroprevalence surveys can estimate the cumulative incidence of SARS-CoV-2 infection in a symptom-independent manner, offering valuable data, including herd immunity, that can inform national and local public health policies. To our knowledge, there have been no large studies reporting seroprevalence in healthcare workers (HCWs) in the state of Arkansas. The objective of this study is to measure SARS-CoV-2 seroprevalence in HCWs in a large tertiary-care healthcare system prior to vaccine availability. Methods The Central Arkansas Veterans Healthcare System offered SARS-CoV-2 antibody testing prior to the widespread availability of vaccines. After Central Arkansas Veterans Healthcare System institutional review board (IRB) approval had been obtained, a retrospective chart review was used to identify all Central Arkansas Veterans Healthcare System HCWs who had undergone SARS-CoV-2 antibody testing from July 1, 2020, to September 30, 2020. Descriptive analysis was performed using Microsoft Excel (Microsoft Corporation, Redmond, Washington, United States). Correlation and regression tests were performed using SAS 9.4 software (SAS Institute Inc., Cary, NC). Results Over the study interval, 170 healthcare personnel had undergone SARS-CoV-2 anti-spike IgG antibody testing. Thirty-seven (21.8%) had positive antibody results. The 37 individuals were mostly women (94.5%), and the average age of the group was 47 years (range 29-69 years). The median antibody titers for those testing positive for antibodies were 10.8 units (range 1.1-58.5). Of the 37 people, 32 had a history of COVID-19 infection proven by reverse transcriptase polymerase chain reaction (RT-PCR). Conclusion Serologic testing is feasible for healthcare workers to document an immune response to a prior infection. In this study of HCWs, the rate of positivity among those tested was 21.8%. Data that do not incorporate the cohort of patients with prior infections will underestimate the impact of prior infections on herd immunity statistics and may misinform public policy.

Role of Rab5 early endosomes in regulating Drosophila gut antibacterial response.

Interactions between prokaryotes and eukaryotes require a dialogue between MAMPs and PRRs. In Drosophila, bacterial peptidoglycan is detected by PGRP receptors. While the components of the signaling cascades activated upon PGN/PGRP interactions are well characterized, little is known about the subcellular events that translate these early signaling steps into target gene transcription. Using a Drosophila enteric infection model, we show that gut-associated bacteria can induce the formation of intracellular PGRP-LE aggregates which colocalized with the early endosome marker Rab5. Combining microscopic and RNA-seq analysis, we demonstrate that RNAi inactivation of the endocytosis pathway in the Drosophila gut affects the expression of essential regulators of the NF-κB response leading not only to a disruption of the immune response locally in the gut but also at the systemic level. This work sheds new light on the involvement of the endocytosis pathway in the control of the gut response to intestinal bacterial infection.

Neural network algorithms predict new diffusion MRI data for multi-compartmental analysis of brain microstructure in a clinical setting.

High angular resolution diffusion imaging (HARDI) is a promising method for advanced analysis of brain microstructure. However, comprehensive HARDI analysis requires multiple acquisitions of diffusion images (multi-shell HARDI), which is time consuming and often impractical in clinical settings. This study aimed to establish neural network models that can predict new diffusion datasets from clinically feasible brain diffusion MRI for multi-shell HARDI. The development included 2 algorithms: multi-layer perceptron (MLP) and convolutional neural network (CNN). Both followed a voxel-based approach for model training (70%), validation (15%), and testing (15%). The investigations involved 2 multi-shell HARDI datasets: 1) 11 healthy subjects from the Human Connectome Project (HCP); and 2) 10 local subjects with multiple sclerosis (MS). To assess outcomes, we conducted neurite orientation dispersion and density imaging using both predicted and original data and compared their orientation dispersion index (ODI) and neurite density index (NDI) in different brain tissues with 2 measures: peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM). Results showed that both models achieved robust predictions, which provided competitive ODI and NDI, especially in brain white matter. The CNN outperformed MLP with the HCP data on both PSNR (p < 0.001) and SSIM (p < 0.01). With the MS data, the models performed similarly. Overall, the optimized neural networks can help generate non-acquired brain diffusion MRI, which will make advanced HARDI analysis possible in clinical practice following further validation. Enabling detailed characterization of brain microstructure will allow enhanced understanding of brain function in both health and disease.

Risk Stratification for Oropharyngeal Squamous Cell Carcinoma Using Texture Analysis on CT - A Step Beyond HPV Status.

Background and Purpose: Human papillomavirus-associated oropharyngeal squamous cell carcinoma (OPSCC) is increasingly prevalent. Despite the overall more favorable outcome, the observed heterogeneous treatment response within this patient group highlights the need for additional means to prognosticate and guide clinical decision-making. Promising prediction models using radiomics from primary OPSCC have been derived. However, no model/s using metastatic lymphadenopathy exist to allow prognostication in those instances when the primary tumor is not seen. The aim of our study was to evaluate whether radiomics using metastatic lymphadenopathy allows for the development of a useful risk assessment model comparable to the primary tumor and whether additional knowledge of the HPV status further improves its prognostic efficacy. Materials and Methods: 80 consecutive patients diagnosed with stage III-IV OPSCC between February 2009 and October 2015, known human papillomavirus status, and pre-treatment CT images were retrospectively identified. Manual segmentation of primary tumor and metastatic lymphadenopathy was performed and the extracted texture features were used to develop multivariate assessment models to prognosticate treatment response. Results: Texture analysis of either the primary or metastatic lymphadenopathy from pre-treatment enhanced CT images can be used to develop models for the stratification of treatment outcomes in OPSCC patients. AUCs range from .78 to .85 for the various OPSCC groups tested, indicating high predictive capability of the models. Conclusions: This preliminary study can form the basis multi-centre trial that may help optimize treatment and improve quality of life in patients with OPSCC in the era of personalized medicine.

Marijuana and the Lung: Evolving Understandings.

Human beings have used marijuana products for centuries. Relatively recent data showing extensive cannabinoid receptors, particularly in the brain, help to explain the impacts of cannabinoids on symptoms/diseases, such as pain and seizures, with major nervous system components. Marijuana can cause bronchitis, but a moderate body of literature suggests that distal airway/parenchymal lung disease does not occur; marijuana does not cause chronic obstructive pulmonary disease and probably does not cause lung cancer, distinctly different from tobacco. Potentials for cognitive impairment and for damage to the developing brain are contextually important as its beneficial uses are explored.

Validation of a machine learning software tool for automated large vessel occlusion detection in patients with suspected acute stroke.

PURPOSE: CT angiography (CTA) is the imaging standard for large vessel occlusion (LVO) detection in patients with acute ischemic stroke. StrokeSENS LVO is an automated tool that utilizes a machine learning algorithm to identify anterior large vessel occlusions (LVO) on CTA. The aim of this study was to test the algorithm's performance in LVO detection in an independent dataset. METHODS: A total of 400 studies (217 LVO, 183 other/no occlusion) read by expert consensus were used for retrospective analysis. The LVO was defined as intracranial internal carotid artery (ICA) occlusion and M1 middle cerebral artery (MCA) occlusion. Software performance in detecting anterior LVO was evaluated using receiver operator characteristics (ROC) analysis, reporting area under the curve (AUC), sensitivity, and specificity. Subgroup analyses were performed to evaluate if performance in detecting LVO differed by subgroups, namely M1 MCA and ICA occlusion sites, and in data stratified by patient age, sex, and CTA acquisition characteristics (slice thickness, kilovoltage tube peak, and scanner manufacturer). RESULTS: AUC, sensitivity, and specificity overall were as follows: 0.939, 0.894, and 0.874, respectively, in the full cohort; 0.927, 0.857, and 0.874, respectively, in the ICA occlusion cohort; 0.945, 0.914, and 0.874, respectively, in the M1 MCA occlusion cohort. Performance did not differ significantly by patient age, sex, or CTA acquisition characteristics. CONCLUSION: The StrokeSENS LVO machine learning algorithm detects anterior LVO with high accuracy from a range of scans in a large dataset.

Association of Stent-Retriever Characteristics in Establishing Successful Reperfusion During Mechanical Thrombectomy : Results from the ESCAPE-NA1 Trial.

BACKGROUND: Successful reperfusion determines the treatment effect of endovascular thrombectomy. We evaluated stent-retriever characteristics and their relation to reperfusion in the ESCAPE-NA1 trial. METHODS: Independent re-scoring of reperfusion grade for each attempt was conducted. The following characteristics were evaluated: stent-retriever length and diameter, thrombus position within stent-retriever, bypass effect, deployment in the superior or inferior MCA trunk, use of balloon guide catheter and distal access catheter. Primary outcome was successful reperfusion defined as expanded thrombolysis in cerebral infarction (eTICI) 2b-3 per attempt. The secondary outcome was successful reperfusion eTICI 2b-3 after the first attempt. Separate regression models for each stent-retriever characteristic and an exploratory multivariable modeling to test the impact of all characteristics on successful reperfusion were built. RESULTS: Of 1105 patients in the trial, 809 with the stent-retriever use (1241 attempts) were included in the primary analysis. The stent-retriever was used as the first-line approach in 751 attempts. A successful attempt was associated with thrombus position within the proximal or middle third of the stent (OR 2.06; 95% CI: 1.24-3.40 and OR 1.92; 95% CI: 1.16-3.15 compared to the distal third respectively) and with bypass effect (OR 1.7; 95% CI: 1.07-2.72). Thrombus position within the proximal or middle third (OR 2.80; 95% CI: 1.47-5.35 and OR 2.05; 95% CI: 1.09-3.84, respectively) was associated with first-pass eTICI 2b-3 reperfusion. In the exploratory analysis accounting for all characteristics, bypass effect was the only independent predictor of eTICI 2b-3 reperfusion (OR 1.95; 95% CI: 1.10-3.46). CONCLUSION: The presence of bypass effect and thrombus positioning within the proximal and middle third of the stent-retriever were strongly associated with successful reperfusion.

Dosimetry of indoor alpha flux belonging to seasonal radon, thoron and their EECs.

Radon (222Rn) and thoron (220Rn) are ubiquitous radioactive noble gases present in the earth's crust. The source term for these gases includes soil and building materials as well. The radiological impact of radon/thoron gases and their decay products on human life is a matter of concern and has been given due attention in research and policy. The present study aims to measure and quantify residential radon/thoron gas and the decay product's concentration and to discuss the associated interpretations for Ludhiana district of Punjab, India. Passive measurement techniques employing a single-entry pinhole dosimeter for gases and direct progeny sensors for the decay product's concentration have been used in this work. The obtained data from these measurements have been analysed using appropriate statistical techniques. The variations have been linked with the changes in the ventilation conditions, building material, room type and altitude. A higher concentration of radon and thoron gas was observed in the winter season for the study region. It was estimated that the contribution of radon and thoron decay products towards the annual average inhalation dose is 75% and 25%, respectively.

Lung microbiome, gut-lung axis and chronic obstructive pulmonary disease.

PURPOSE OF REVIEW: To review recent data on the microbiome of the lungs and how it changes with the evolution of COPD. To explore initial data with respect to COPD and the gut-lung axis. An expanded understanding of the pathogenesis of COPD may lead to new therapeutic targets. RECENT FINDINGS: Intermittent pulmonary seeding is essential to health. The lung inflammation of chronic obstructive pulmonary disease (COPD) appears to change the lung milieu such that there is a shift in the microbiome of the lung as COPD progresses. Current data contain internal contradictions, but viewed in to suggest that the lung microbiome participates in the ongoing process of inflammation and destruction (in contrast to the role of the 'healthy lung' microbiome). Gut and lung 'communicate' and share some functions. COPD is associated with increased intestinal permeability (a dysfunction associated with inflammation). COPD has an impact upon the gastrointestinal microbiome. The gastrointestinal tract may, thus play a role in the progression of COPD. SUMMARY: Lung injury/inflammation alters the milieu of the lung and favors an evolving microbiome, which reflects and probably participates in the processes of inflammation and injury. There is some evidence that the gastrointestinal tract participates in that inflammatory process.

Management and outcome of patients with acute ischemic stroke and tandem carotid occlusion in the ESCAPE-NA1 trial.

BACKGROUND: The optimal treatment and prognosis for stroke patients with tandem cervical carotid occlusion are unclear. We analyzed outcomes and treatment strategies of tandem occlusion patients in the ESCAPE-NA1 trial. METHODS: ESCAPE-NA1 was a multicenter international randomized trial of nerinetide versus placebo in 1105 patients with acute ischemic stroke who underwent endovascular treatment. We defined tandem occlusions as complete occlusion of the cervical internal carotid artery (ICA) on catheter angiography, in addition to a proximal ipsilateral intracranial large vessel occlusion. Baseline characteristics and outcome parameters were compared between patients with tandem occlusions versus those without, and between patients with tandem occlusion who underwent ICA stenting versus those who did not. The influence of tandem occlusions on functional outcome was analyzed using multivariable regression modeling. RESULTS: Among 115/1105 patients (10.4%) with tandem occlusions, 62 (53.9%) received stenting for the cervical ICA occlusion. Of these, 46 (74.2%) were stented after and 16 (25.8%) before the intracranial thrombectomy. A modified Rankin Score (mRS) of 0-2 at 90 days was achieved in 82/115 patients (71.3%) with tandem occlusions compared with 579/981 (59.5%) patients without tandem occlusions. Tandem occlusion did not impact functional outcome in the adjusted analysis (OR 1.5, 95% CI 0.95 to 2.4). Among the subgroup of patients with tandem occlusion, cervical carotid stenting was not associated with different outcomes compared with no stenting (mRS 0-2: 75.8% vs 66.0%, adjusted OR 2.0, 95% CI 0.8 to 5.1). CONCLUSIONS: Tandem cervical carotid occlusion in patients with acute large vessel stroke did not lower the odds of good functional outcome in our study. Functional outcomes were similar irrespective of the management of the cervical ICA occlusion (stenting vs not stenting).