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1.
J Orthop Res ; 41(3): 698-704, 2023 03.
Article in English | MEDLINE | ID: mdl-35716162

ABSTRACT

The purpose of this study was to determine if muscle activity of the biceps followed by isometric flexion changes T2 measured in the biceps. It is hypothesized that an increase in T2 will be observed in the biceps but not in the triceps after flexion exercise. Ten healthy volunteers were imaged with a one-channel neck coil while seated in a 0.5 T upright open magnetic resonance imaging (MRI) scanner using a three-dimensional double echo steady-state (DESS) sequence. Volunteers were imaged while relaxing their arm for 10, 20, and 30 min during an isometric biceps flexion immediately following performance of biceps curls to exhaustion, and again after relaxing for 10 and 20 min. Voxel-wise T2 was calculated by fitting to a DESS signal equation in regions segmented at muscle centers to determine mean T2 . During isometric biceps flexion immediately following biceps curls, mean T2 increased (average 33%, p < 0.05) in the biceps but not in the triceps. By 20 min after curls, mean T2 decreased (p < 0.05), and was near preactivity values. In contrast, there was no change in triceps T2 across any activity or postactivity time points. Intra-rater repeatability was excellent (ICC: 0.90-0.97). This study demonstrated that measuring T2 in an active muscle is feasible using a DESS sequence in an upright open MRI scanner. This could enable the study of muscle function while the muscle is working and weight-bearing, rather than of the "fatigue" of the muscles after activity. In comparison to electromyography, MRI also enables the study of deep muscles and allows simultaneous assessment of activity and function.


Subject(s)
Muscle Contraction , Muscle, Skeletal , Humans , Muscle, Skeletal/physiology , Electromyography , Muscle Contraction/physiology , Magnetic Resonance Imaging/methods
2.
Cureus ; 14(11): e31000, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36475168

ABSTRACT

OBJECTIVES: To determine the impact of having private health insurance during the period of maternity on low birth-weight (LBW) infants. METHODS: This retrospective case-control study was carried out at a tertiary care hospital in Tabuk, Saudi Arabia, between January 2020 and January 2021. Using non-probability sampling, secondary medical data were obtained at the Department of Obstetrics & Gynecology from two groups: insured and non-insured mothers who had 150 LBW infants (LBWI) (<2.5 kg) as well as normal newborns. Data were analyzed using SPSS, version 24 (IBM Corp., Armonk, NY). A univariate analysis was performed for each variable followed by a logistic regression analysis to explain the relationship between the dependent (LBW) and independent variables (health insurance status, prenatal care, and inter-pregnancy interval). RESULTS: Out of 300 mothers, the majority were in the age group 21-34 years (86%). The LBWI mothers were insured in about 55% of cases. Around 43% had insurance for 1-2 years, and 44.7% of insured mothers were covered by a "class A" health plan. The findings revealed a significant correlation between the duration of maternal insurance coverage period and LBW; it reduced the risk of LBW by 95% CI. The inter-pregnancy interval was 51.3%, with a p-value of 0.33. CONCLUSION: Private health insurance offers coverage, stability, and consistency in Saudi Arabia, which results in better birth outcomes by decreasing both infant mortality and morbidity rates among insured females.

3.
EClinicalMedicine ; 50: 101534, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35812989

ABSTRACT

Background: 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. Methods: 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). Findings: 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). Interpretation: 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. Funding: Toronto General and Western Hospital Foundation.

4.
Viruses ; 14(6)2022 05 24.
Article in English | MEDLINE | ID: mdl-35746597

ABSTRACT

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.


Subject(s)
COVID-19 , Rabies Vaccines , Rabies virus , Rabies , Viral Vaccines , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Cricetinae , Humans , Rabies/prevention & control , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus
5.
Spine (Phila Pa 1976) ; 47(16): 1179-1186, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-34919072

ABSTRACT

STUDY DESIGN: Randomized trial. OBJECTIVE: To implement an algorithm enabling the automated segmentation of spinal muscles from open magnetic resonance images in healthy volunteers and patients with adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA: Understanding spinal muscle anatomy is critical to diagnosing and treating spinal deformity.Muscle boundaries can be extrapolated from medical images using segmentation, which is usually done manually by clinical experts and remains complicated and time-consuming. METHODS: Three groups were examined: two healthy volunteer groups (N = 6 for each group) and one ASD group (N = 8 patients) were imaged at the lumbar and thoracic regions of the spine in an upright open magnetic resonance imaging scanner while maintaining different postures (various seated, standing, and supine). For each group and region, a selection of regions of interest (ROIs) was manually segmented. A multiscale pyramid two-dimensional convolutional neural network was implemented to automatically segment all defined ROIs. A five-fold crossvalidation method was applied and distinct models were trained for each resulting set and group and evaluated using Dice coefficients calculated between the model output and the manually segmented target. RESULTS: Good to excellent results were found across all ROIs for the ASD (Dice coefficient >0.76) and healthy (dice coefficient > 0.86) groups. CONCLUSION: This study represents a fundamental step toward the development of an automated spinal muscle properties extraction pipeline, which will ultimately allow clinicians to have easier access to patient-specific simulations, diagnosis, and treatment.


Subject(s)
Magnetic Resonance Imaging , Neural Networks, Computer , Adult , Algorithms , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Muscles , Spine
6.
Sci Rep ; 11(1): 20127, 2021 10 11.
Article in English | MEDLINE | ID: mdl-34635683

ABSTRACT

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.


Subject(s)
Bone Retroversion/physiopathology , Lordosis/physiopathology , Lumbar Vertebrae/anatomy & histology , Magnetic Resonance Imaging/methods , Muscles/anatomy & histology , Pelvic Bones/anatomy & histology , Pelvis/anatomy & histology , Adult , Bone Retroversion/pathology , Cross-Sectional Studies , Feasibility Studies , Female , Humans , Male , Middle Aged , Pilot Projects , Range of Motion, Articular , Standing Position , Young Adult
7.
Eur Spine J ; 29(9): 2306-2318, 2020 09.
Article in English | MEDLINE | ID: mdl-32335742

ABSTRACT

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.


Subject(s)
Lumbosacral Region , Posture , Humans , Lumbar Vertebrae/diagnostic imaging , Magnetic Resonance Imaging , Paraspinal Muscles/diagnostic imaging
8.
Cureus ; 11(2): e4160, 2019 Feb 28.
Article in English | MEDLINE | ID: mdl-31058043

ABSTRACT

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.

9.
Proc Natl Acad Sci U S A ; 114(12): E2293-E2302, 2017 03 21.
Article in English | MEDLINE | ID: mdl-28265064

ABSTRACT

Organ-on-a-chip systems are miniaturized microfluidic 3D human tissue and organ models designed to recapitulate the important biological and physiological parameters of their in vivo counterparts. They have recently emerged as a viable platform for personalized medicine and drug screening. These in vitro models, featuring biomimetic compositions, architectures, and functions, are expected to replace the conventional planar, static cell cultures and bridge the gap between the currently used preclinical animal models and the human body. Multiple organoid models may be further connected together through the microfluidics in a similar manner in which they are arranged in vivo, providing the capability to analyze multiorgan interactions. Although a wide variety of human organ-on-a-chip models have been created, there are limited efforts on the integration of multisensor systems. However, in situ continual measuring is critical in precise assessment of the microenvironment parameters and the dynamic responses of the organs to pharmaceutical compounds over extended periods of time. In addition, automated and noninvasive capability is strongly desired for long-term monitoring. Here, we report a fully integrated modular physical, biochemical, and optical sensing platform through a fluidics-routing breadboard, which operates organ-on-a-chip units in a continual, dynamic, and automated manner. We believe that this platform technology has paved a potential avenue to promote the performance of current organ-on-a-chip models in drug screening by integrating a multitude of real-time sensors to achieve automated in situ monitoring of biophysical and biochemical parameters.


Subject(s)
Automation/methods , Biosensing Techniques/methods , Drug Evaluation, Preclinical/methods , Organoids/physiology , Automation/instrumentation , Biosensing Techniques/instrumentation , Drug Evaluation, Preclinical/instrumentation , Heart/physiology , Humans , Liver/chemistry , Liver/physiology , Microfluidics , Models, Biological , Myocardium , Organoids/chemistry , Organoids/drug effects
10.
J Endovasc Ther ; 24(1): 35-46, 2017 02.
Article in English | MEDLINE | ID: mdl-27659155

ABSTRACT

PURPOSE: To test and validate magnetic resonance imaging (MRI) sequences for peripheral artery lesion characterization and relate the MRI characteristics to the amount of force required for a guidewire to puncture peripheral chronic total occlusions (CTOs) as a surrogate for immediate failure of endovascular therapy. METHODS: Diseased superficial femoral, popliteal, and tibial artery segments containing 55 atherosclerotic lesions were excised from the amputated limbs of 7 patients with critical limb ischemia. The lesions were imaged at high resolution (75 µm3 voxels) with T2-weighted (T2W) and ultrashort echo time (UTE) sequences on a 7-T MR scanner. The MR images (n=15) were validated with micro-computed tomography and histology. CTOs (n=40) were classified by their MR signal characteristics as "soft" (signals indicating fat, thrombus, microchannels, or loose fibrous tissue), "hard" (collagen and/or speckled calcium signals), or "calcified" (calcified nodule signals). A 2-kg load cell advanced the back end of a 0.035-inch stiff guidewire at a fixed displacement rate (0.05 mm/s) through the CTOs, and the forces required to cross each lesion were measured. RESULTS: T2W images showed fat as hyperintense and hardened tissue as hypointense. Calcium and thrombus appeared as a signal void in conventional MRI sequences but were easily identified in UTE images (thrombus was hyperintense and calcium hypointense). MRI accurately differentiated "hard," "soft," and "calcified" CTOs based on associated guidewire puncture force. The guidewire could not enter "calcified" CTOs (n=6) at all. "Hard" CTOs (n=9) required a significantly higher (p<0.001) puncture force of 1.71±0.51 N vs 0.43±0.36 N for "soft" CTOs (n=25). CONCLUSION: MRI characteristics of PAD lesions correlate with guidewire puncture forces, an important aspect of crossability. Future work will determine if clinical MR scanners can be used to predict success in peripheral vascular interventions.


Subject(s)
Endovascular Procedures , Femoral Artery/diagnostic imaging , Magnetic Resonance Imaging , Peripheral Arterial Disease/diagnostic imaging , Peripheral Arterial Disease/therapy , Plaque, Atherosclerotic , Popliteal Artery/diagnostic imaging , Tibial Arteries/diagnostic imaging , Vascular Calcification/diagnostic imaging , Vascular Calcification/therapy , Aged , Aged, 80 and over , Clinical Decision-Making , Female , Femoral Artery/pathology , Humans , Male , Middle Aged , Patient Selection , Peripheral Arterial Disease/pathology , Popliteal Artery/pathology , Predictive Value of Tests , Punctures , Reproducibility of Results , Tibial Arteries/pathology , Vascular Calcification/pathology
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