We measured ultrafine particle number concentration (PNC) and fine particulate matter mass concentration (PM2.5) levels in public buses and private cars under three conditions: windows open, windows ...closed with air recirculation off, and windows closed with air recirculation on in Dhaka, Bangladesh—an extremely polluted megacity in South Asia. We collected measurements on ∼10 repeated round trips on unique days for each selected transportation mode, covering various routes that spanned multiple arterial roads over several months (January to March 2020 and November to December 2020) and different times of the day to account for the variability in traffic and meteorological conditions. We used a condensation particle counter (CPC) to measure PNC and a PurpleAir sensor to measure PM2.5 mass concentrations. We applied corrections to the raw data and analyzed quality-assured data to investigate exposure differences across modes, pollutants, locations, and times. Public buses and private cars with open windows had mean PNC levels of 112,000 # cm−3 and 117,000 # cm−3, approximately 5–6 times higher than the mean urban background level of around 20,000 # cm−3. PM2.5 levels in these vehicles were approximately ∼100 μg m−3, about 20% higher than the urban background PM2.5 level of 85 μg m−3. With closed windows and air recirculation off, concentrations were 15% lower for PNC and 10% lower for PM2.5. Under closing windows and keeping air recirculation on, mean PNC and PM2.5 levels were 60,000 # cm−3 and 70 μg m−3, respectively, representing a 50% reduction for PNC and a 30% reduction for PM2.5 compared to open windows. Our findings suggest that commuters in public buses and private cars with open windows have higher and similar exposure levels, whereas those commute in private cars with closed windows and air recirculation on have lower exposure levels.
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•We quantified commuting air pollution exposure in Dhaka, Bangladesh by collecting PNC and PM2.5 data inside public buses and private cars.•Public buses and cars with open windows in Dhaka exhibited PNC levels 5–6 times higher and PM2.5 levels 20% higher than those at urban background location.•Closing car windows and keeping the air recirculation on reduced in-car PNC exposure by 50% and PM2.5 by 30%, an actionable step for exposure reduction.
The study reports the morphology and optical properties of a variety of cellulose nanocrystals (CNC) obtained from different natural sources with different dimensions and composition. A library of ...CNCs components with different dimensions, sulfate contents, and crystallite sizes was prepared under identical hydrolysis conditions from five distinct sources representing traditional choices ranging from soft and hard wood pulps to microcrystalline cellulose. High-resolution atomic force microscopy, scanning electron microscopy, scanning transmission electron microscopy, and X-ray diffraction confirmed that all CNCs have a well-defined needle-like morphology with different aspect ratios and axi-asymmetric cross-sections. Varying the cellulose sources resulted in wide variability of the CNC dimensions, including length (120–210 nm), aspect ratio (30–70), height (2.9–3.6 nm), and width (6–11 nm). Specifically, the CNCs from microcrystalline sources have large cross-sectional dimensions and produce straight CNC bundles, but CNCs from wood pulps have small cross-sections and form twisted bundles of a few individual nanocrystals. Chemical composition and surface potentials were found to be less critical to the resulting chiral characteristics and structural colors while the CNCs with high aspect ratios form chiral films with large pitch values and thus longer wavelengths of selective reflection. Such flexible chiral CNC materials with controlled optical signature can be further considered for development of advanced materials for colorimetric sensors, tunable and active photonic materials, optical coatings, chiral inks and 3D printed photonic structures.
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•High-resolution atomic force microscopy to probe morphology of CNCs from different sources.•We explore the relationship between properties of CNCs and structure of their solid chiral phases.•Local aggregation of CNCs, such as twisted bundles or parallel-packed straight nanocrystals are discussed.
Because of the potential for high aerosol transmission during pulmonary function testing and pulmonary procedures, performing these tests and procedures must be considered carefully during the ...coronavirus disease-2019 (COVID-19) pandemic. Much has been learned about the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by aerosols and the potential for such transmission through pulmonary function tests and pulmonary procedures, and subsequently preventative practices have been enhanced and developed to reduce the risk of transmission of virus to patients and personnel. This article reviews what is known about the potential for transmission of SARS-CoV-2 during pulmonary function testing and pulmonary procedures and the recommended mitigation steps to prevent the spread of COVID-19.
Cryosurgical techniques are employed for diagnostic and therapeutic bronchoscopy and serve as important tools for the management of pulmonary diseases. The diagnosis of interstitial lung disease ...requires multidisciplinary team discussions after a thorough assessment of history, physical exam, computed tomography, and lung-function testing. However, histological diagnosis is required in selected patients. Surgical lung biopsy has been the gold standard but this can be associated with increased morbidity and mortality. Transbronchial lung cryobiopsy is an emerging technique and multiple studies have shown that it has a high diagnostic yield with a good safety profile. There is wide procedural variability and the optimal technique for cryobiopsy is still under investigation. There is emerging data that demonstrate that cryobiopsy is safe and highly accurate in the diagnosis of thoracic malignancies. Furthermore, cryorecanalization procedures are a useful adjunct for the palliation of tumors in patients with central airway obstruction. One should keep in mind that these procedures are not free from complications and should be carried out in a specialized center by a trained and experienced bronchoscopy team. We present a review of the literature on the diagnostic and therapeutic utility of bronchoscopy-guided cryosurgical procedures and their safety profile.
This study investigated feasibility of imaging lumbopelvic musculature and geometry in tandem using upright magnetic resonance imaging (MRI) in asymptomatic adults, and explored the effect of pelvic ...retroversion on lumbopelvic musculature and geometry. Six asymptomatic volunteers were imaged (0.5 T upright MRI) in 4 postures: standing, standing pelvic retroversion, standing 30° flexion, and supine. Measures included muscle morphometry cross-sectional area (CSA), circularity, radius, and angle of the gluteus and iliopsoas, and pelvic geometry pelvic tilt (PT), pelvic incidence (PI), sacral slope (SS), L3-S1 lumbar lordosis (LL) L3-coccyx. With four volunteers repeating postures, and three raters assessing repeatability, there was generally good repeatability ICC(3,1) 0.80-0.97. Retroversion had level dependent effects on muscle measures, for example gluteus CSA and circularity increased (up to 22%). Retroversion increased PT, decreased SS, and decreased L3-S1 LL, but did not affect PI. Gluteus CSA and circularity also had level-specific correlations with PT, SS, and L3-S1 LL. Overall, upright MRI of the lumbopelvic musculature is feasible with good reproducibility, and the morphometry of the involved muscles significantly changes with posture. This finding has the potential to be used for clinical consideration in designing and performing future studies with greater number of healthy subjects and patients.
Purpose
To assess the effect of upright, seated, and supine postures on lumbar muscle morphometry at multiple spinal levels and for multiple muscles.
Methods
Six asymptomatic volunteers were imaged ...(0.5 T upright open MRI) in 7 postures (standing, standing holding 8 kg, standing 45° flexion, seated 45° flexion, seated upright, seated 45° extension, and supine), with scans at L3/L4, L4/L5, and L5/S1. Muscle cross-sectional area (CSA) and muscle position with respect to the vertebral body centroid (radius and angle) were measured for the multifidus/erector spinae combined and psoas major muscles.
Results
Posture significantly affected the multifidus/erector spinae CSA with decreasing CSA from straight postures (standing and supine) to seated and flexed postures (up to 19%). Psoas major CSA significantly varied with vertebral level with opposite trends due to posture at L3/L4 (increasing CSA, up to 36%) and L5/S1 (decreasing CSA, up to 40%) with sitting/flexion. For both muscle groups, radius and angle followed similar trends with decreasing radius (up to 5%) and increasing angle (up to 12%) with seated/flexed postures. CSA and lumbar lordosis had some correlation (multifidus/erector spinae L4/L5 and L5/S1,
r
= 0.37–0.45; PS L3/L4 left,
r
= − 0.51). There was generally good repeatability (average ICC(3, 1): posture = 0.81, intra = 0.89, inter = 0.82).
Conclusion
Changes in multifidus/erector spinae muscle CSA likely represent muscles stretching between upright and seated/flexed postures. For the psoas major, the differential level effect suggests that changing three-dimensional muscle morphometry with flexion is not uniform along the muscle length. The muscle and spinal level-dependent effects of posture and spinal curvature correlation, including muscle CSA and position, highlight considering measured muscle morphometry from different postures in spine models.
Non-alcoholic steatohepatitis (NASH) is the second-leading indication for liver transplantation (LT) worldwide and is projected to become the leading indication. Our study aimed to determine clinical ...variables that predict post-LT survival in NASH.
A systematic review and meta-analysis was performed. On June 18, 2020 and April 28, 2022, Ovid MEDLINE ALL, Ovid Embase, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials were searched. No date limits were applied. Inclusion criteria specified the type of study and our study's population/comparison and outcome/timepoints. Pediatric, animal, retransplantation-only, and studies classifying cryptogenic cirrhosis patients with body mass index (BMI) <30 as NASH were excluded. Studies with duplicate cohorts and missing information were excluded from the meta-analysis. Studies were appraised using the Newcastle–Ottawa Scale. This study was preregistered in PROSPERO (CRD42020196915).
Out of 8583 studies identified, 25 studies were included in the systematic review, while 5 studies were included in the meta-analysis. Our quantitative review suggested that the following variables were predictive of post-LT NASH patient survival: recipient age, functional status, pre-LT hepatoma, model for end-stage liver disease (MELD) score, diabetes mellitus (DM), pre-LT dialysis, hepatic encephalopathy, portal vein thrombosis, hospitalization/ICU at LT, and year of LT. Predictors of graft survival included recipient age, BMI, pre-LT dialysis, and DM. Our pooled meta-analyses included five predictors of patient survival. Increased patient mortality was associated with older recipient age (HR=2·07, 95%CI: 1·71-2·50, I2=0, τ2=0, p=0·40) and pretransplant DM (HR=1·18, 95%CI: 1·08-1·28, I2=0, τ2=0, p=0·76).
Our systematic review and meta-analysis aimed to synthesise predictive variables of mortality in LT NASH patients. Clinically, this might help to identify modifiable risk factors that can be optimized in the post-transplant setting to improve patient outcomes and optimises decision making in the resource-limited LT setting.
Toronto General and Western Hospital Foundation.
Introduction Clinical empathy is the ability to comprehend the perspectives, feelings, and situation of the patients. Clinical empathy instills a sense of satisfaction in the patient. It also ...facilitates the healthcare provider (HCPs) in taking more sincere and logical clinical decisions. Although there have been numerous studied conducted to explore the pattern of clinical empathy among medical students, the results are mixed and not consistent. Methods This is a cross-sectional, observational study conducted among medical students of Ghulam Muhammad Mahar Medical College in August 2018. Two hundred and seven out of 500 students of all five years completed the study after informed consent. All students completed the 20-item Jefferson Scale of Empathy-Student Version (JSE-S). Data were entered and analyzed using SPSS version 22 (SPSS Inc, Chicago, IL, USA). The internal consistency of JSE-S was 0.71. Frequencies and percentages were calculated for students' ages and genders. Mean and standard deviation (SD) were calculated for continuous variables. Group comparisons of the empathy scores were conducted using t-test and one-way analysis of variance (ANOVA). p<0.05 was considered as the significant level. Results There were 93 (44.9%) male and 114 (55.1%) female students. Their mean ± SD age was 20.85 ± 2.27 years (range: 17 to 26 years). The mean ± SD empathy score of all students was 98.11 ± 12.31 (range: 20-140). The mean empathy score was categorized according to gender, year of education, and career preference. Females showed a significantly higher empathy score. The lowest empathy was seen for the final year and the highest for the first year. On all three subscales of (JSE-S) - perspective taking, compassionate care, and walking in patients' shoes - students with "people-oriented" career preference scored higher. Conclusion JSE-S is a self-administered and self-perceived inventory, which reports declining empathy in medical students with ascending years of education. Qualitative studies that can assess the empathy levels from the patients' perspective are the need of the hour to decide whether or not empathy is a real phenomenon.
Without sufficient herd immunity through either vaccination or natural infection, the coronavirus disease 2019 pandemic is unlikely to be controlled. Waning immunity with the currently approved ...vaccines suggests the need to evaluate vaccines causing the induction of long-term responses. Here, we report the immunogenicity and efficacy of our adjuvanted single-dose Rabies-vectored SARS-CoV-2 S1 vaccine, CORAVAX, in hamsters. CORAVAX induces high SARS-CoV-2 S1-specific and virus-neutralizing antibodies (VNAs) that prevent weight loss, viral loads, disease, lung inflammation, and the cytokine storm in hamsters. We also observed high Rabies VNA titers. In summary, CORAVAX is a promising dual-antigen vaccine candidate for clinical evaluation against SARS-CoV-2 and Rabies virus.
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