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1.
Malays J Med Sci ; 31(3): 229-240, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38984237

RESUMEN

Background: This study sought to compare the prevalence of underweight and overweight among ever-married, non-pregnant women of reproductive age in Bangladesh by urban or rural residency status. Methods: This study used Bangladesh Demographic and Health Survey (BDHS), 2017 data. Cross-sectional study design with two-stage stratified sampling method was employed. A sample of ever-married non-pregnant women of reproductive age was selected and multinomial logistic regression was utilised in analysis. Results: It was found that around half of rural women (45.0%, N = 4,934) and more than half of urban women (60.3%, n = 3,913) were overweight. Nearly one in seven rural women (14.0%, n = 1,537) and 1 in 12 urban women (9.0%, n = 564) were reported as underweight. Our analyses revealed that being overweight was substantially connected with age, husband's occupation, economic status, television access, and division for both urban and rural areas. Women from poor households were significantly more likely to be underweight than women from middle- income households for both urban (P < 0.05; OR: 1.41; 95% CI: 1.03, 1.94) and rural (P < 0.05; OR: 1.23; 95% CI: 1.04, 1.46) areas. Interestingly, women without television access both in urban (P < 0.001; OR = 0.78; 95% CI: 0.67, 0.91) and rural (P < 0.001; OR = 0.75; 95% CI: 0.68, 0.84) areas had an inverse association with overweight/obesity compared to women with television access. In both areas, women in Sylhet and Mymensingh had higher likelihood of being underweight than Barisal division. Additionally, in both residential zones, women in Sylhet had lower likelihood of being overweight than Barisal division. Conclusion: This study reveals that multiple characteristics are linked to both overweight and underweight among ever-married, non-pregnant women of reproductive age in Bangladesh. Addressing these variables should be a priority in public health efforts to combat the dual challenge of malnutrition in Bangladesh.

2.
J Transl Med ; 21(1): 582, 2023 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-37649088

RESUMEN

Over the last five decades, breast density has been associated with increased risk of developing breast cancer. Mammographically dense breasts are considered those belonging to the heterogeneously dense breasts, and extremely dense breasts subgroups according to the American College of Radiology's Breast Imaging Reporting and Data System (BI-RADS). There is a statistically significant correlation between the increased mammographic density and the presence of more glandular tissue alone. However, the strength of this correlation is weak. Although the mechanisms driving breast density-related tumor initiation and progression are still unknown, there is evidence suggesting that certain molecular pathways participating in epithelial-stromal interactions may play a pivotal role in the deposition of fibrillar collagen, increased matrix stiffness, and cell migration that favor breast density and carcinogenesis. This article describes these molecular mechanisms as potential "landscapers" for breast density-related cancer. We also introduce the term "Breast Compactness" to reflect collagen density of breast tissue on chest CT scan and the use of breast stiffness measurements as imaging biomarkers for breast cancer screening and risk stratification.


Asunto(s)
Neoplasias de la Mama , Radiología , Humanos , Femenino , Neoplasias de la Mama/diagnóstico por imagen , Mama/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Factores de Riesgo
3.
J Vasc Surg ; 61(3): 690-7, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25499716

RESUMEN

OBJECTIVE: As investigations into nonsurgical treatment for atherosclerosis expand, the measurement of plaque regression and progression has become an important end point to evaluate. Measurements of three-dimensional (3D) plaque volume are more reliable and sensitive to change than are traditional estimates of stenosis severity or cross-sectional area. 3D ultrasound (3D US) imaging may allow monitoring of plaque volume changes but has not been used routinely due to the cumbersome motorized units required to drive transducers. We investigated the variability, reliability, and the least amount of change detectable by 1D plaque measures, as well as 2D and 3D measures of plaque morphometry, that can be applied in a clinical environment. METHODS: 3D US imaging was obtained in 10 patients with carotid stenosis. The lumen and outer wall boundaries were outlined in serial cross-sectional images 1 mm apart. Three observers manually segmented vessel wall volumes (VWVs), and the segmentation was repeated again 4 weeks later. This allowed measurement of interobserver and intraobserver variability of 6 pairs of observations. We measured Bland-Altman statistics, intraclass correlation coefficients, coefficient of variability, and the minimum detectable plaque change for each morphometric measure. RESULTS: The mean VWV of carotid lesions in the study was 1276.8 mm(3) (range, 620.6-1956.3 mm(3)). Bland-Altman plots demonstrated low interobserver and intraobserver variability. The interobserver variability of volume measurements as a function of mean volume was 14.8% and interobserver variability was 8.9%. Reliability was 87% as quantified by the interclass correlation and was 95% by the intraclass correlation. The least detectable change in VWV was 12.9% for interobserver variability and 4.5% for intraobserver variability for the three observers. CONCLUSIONS: Carotid plaque diameter measurements from B-mode images have high variability. Plaque burden, as estimated by VWV, can be measured reliably with a 3D US technique using a clinical scanner. The volumetric change, with 95% confidence, that must be observed to establish that a plaque has undergone growth or regression is ∼12.9% for different observers and 4.5% for the same observer performing the follow-up study.


Asunto(s)
Arterias Carótidas/diagnóstico por imagen , Estenosis Carotídea/diagnóstico por imagen , Imagenología Tridimensional , Placa Aterosclerótica , Ultrasonografía Doppler Dúplex , Anciano , Velocidad del Flujo Sanguíneo , Arterias Carótidas/fisiopatología , Estenosis Carotídea/fisiopatología , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Flujo Sanguíneo Regional , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
4.
Malays J Med Sci ; 21(3): 31-7, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-25246833

RESUMEN

BACKGROUND: Humoral and cellular immune responses are associated with protection against extracellular and intracellular pathogens, respectively. In the present study, we evaluated the effect of receiving human secretory immunoglobulin A (hsIgA) on the histopathology of the lungs of mice challenged with virulent Mycobacterium tuberculosis. METHODS: The hsIgA was purified from human colostrum and administered to Balb/c mice by the intranasal route prior to infection with M. tuberculosis or in a pre-incubated formulation with mycobacteria, with the principal aim to study its effect on qualitative pulmonary histopathology. RESULTS: The intranasal administration of hsIgA and the pre-incubation of mycobacteria with this preparation was associated with the presence of organised granulomas with signs of immune activation and histological features related to efficient disease control. This effect was highly evident during the late stage of infection (60 days), as demonstrated by numerous organised granulomas with numerous activated macrophages in the lungs of treated mice. CONCLUSION: The administration of hsIgA to mice before intratracheal infection with M. tuberculosis or the pre-incubation of the bacteria with the antibody formulation induced the formation of well-organised granulomas and inflammatory lesions in lungs compared with non-treated animals which correlates with the protective effect already demonstrated by these antibody formulations.

5.
IEEE Trans Biomed Eng ; 71(2): 607-620, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37647191

RESUMEN

OBJECTIVE: To assess viscoelasticity, a pathologically relevant biomarker, shear wave elastography (SWE) generally uses phase velocity (PV) dispersion relationship generated via pulsed acoustic radiation force (ARF) excitation pulse. In this study, a multi-frequency oscillation (MFO)- excitation pulse with higher weight to higher frequencies is proposed to generate PV images via the generation of motion with energy concentrated at the target frequencies in contrast to the broadband frequency motion generated in pulsed SWE (PSWE). METHODS: The feasibility of MFO-SWE to generate PV images at 100 to 1000 Hz in steps of 100 Hz was investigated by imaging 6 and 70 kPa inclusions with 6.5 and 10.4 mm diameter and ex vivo bovine liver with and without the presence of an aberration layer and chicken muscle ex vivo, and 4T1 mouse breast tumor, in vivo with comparisons to PSWE. RESULTS: MFO-SWE-derived CNR was statistically higher than PSWE for 6 kPa (both with and without aberration) and 70 kPa (with aberration) inclusions and derived SNR of the liver was statistically higher than PSWE at higher frequency (600-1000 Hz). Quantitatively, at 600-1000 Hz, MFO-SWE improved CNR of inclusions (without and with) aberration on an average by (8.2 and 156)% and of the tumor by 122%, respectively, and improved SNR of the liver (without and with) aberration by (20.2 and 51.5)% and of chicken muscle by 72%, respectively compared to the PSWE. CONCLUSIONS AND SIGNIFICANCE: These results indicate the advantages of MFO-SWE to improve PV estimation at higher frequencies which could improve viscoelasticity quantification and feature delineation.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Animales , Bovinos , Ratones , Biomarcadores , Diagnóstico por Imagen de Elasticidad/métodos , Estudios de Factibilidad , Hígado/diagnóstico por imagen , Hígado/fisiología , Movimiento (Física) , Pollos
6.
Artículo en Inglés | MEDLINE | ID: mdl-37917522

RESUMEN

Harmonic motion imaging (HMI) is an ultrasound elastography technique that estimates the viscoelastic properties of tissues by inducing localized oscillatory motion using focused ultrasound (FUS). The resulting displacement, assumed to be inversely proportional to the tissue local stiffness, is estimated using an imaging array based on RF speckle tracking. In conventional HMI, this is accomplished with plane-wave (PW) imaging, which inherently suffers from low lateral resolution. Coherent PW compounding (PWC) leverages spatial and temporal resolution using synthetic focusing in transmit. In this study, we introduced focused imaging with parallel tracking in HMI and compared parallel tracking of various transmit F-numbers (F/2.6, 3, 4, and 5) qualitatively and quantitatively with PW and PWC imaging at various compounded angle ranges (6°, 12°, and 18°). An in silico model of a 56-kPa spherical inclusion (diameter: 3.6 mm) embedded in a 5.3-kPa background and a 5.3-kPa elastic phantom with cylindrical inclusions (Young's moduli: 22-56 kPa, diameters: 2.0-8.6 mm) were imaged to assess different tracking beam sequences. Speckle biasing in displacement estimation associated with parallel tracking was also investigated and concluded to be negligible in HMI. Parallel tracking in receive (Rx) resulted in 2%-7% and 8%-12% increase compared to PW imaging ( ) in HMI contrast and contrast-to-noise ratio in silico and phantoms. Focused imaging with parallel tracking in Rx was concluded to be most robust among PW and PWC imaging for displacement estimation, and its preclinical feasibility was demonstrated in postsurgical human cancerous breast tissue specimens and in vivo murine models of breast cancer.


Asunto(s)
Neoplasias de la Mama , Diagnóstico por Imagen de Elasticidad , Animales , Humanos , Ratones , Femenino , Ultrasonografía/métodos , Módulo de Elasticidad , Diagnóstico por Imagen de Elasticidad/métodos , Fantasmas de Imagen , Movimiento (Física)
7.
bioRxiv ; 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38617295

RESUMEN

Focused ultrasound (FUS) stimulation is a promising neuromodulation technique with the merits of non-invasiveness, high spatial resolution, and deep penetration depth. However, simultaneous imaging of FUS-induced brain tissue displacement and the subsequent effect of FUS stimulation on brain hemodynamics has proven challenging thus far. In addition, earlier studies lack in situ confirmation of targeting except for the magnetic resonance imaging-guided FUS system-based studies. The purpose of this study is 1) to introduce a fully ultrasonic approach to in situ target, modulate neuronal activity, and monitor the resultant neuromodulation effect by respectively leveraging displacement imaging, FUS, and functional ultrasound (fUS) imaging, and 2) to investigate FUS-evoked cerebral blood volume (CBV) response and the relationship between CBV and displacement. We performed displacement imaging on craniotomized mice to confirm the in targeting for neuromodulation site. We recorded hemodynamic responses evoked by FUS and fUS revealed an ipsilateral CBV increase that peaks at 4 s post-FUS. We saw a stronger hemodynamic activation in the subcortical region than cortical, showing good agreement with the brain elasticity map that can also be obtained using a similar methodology. We observed dose-dependent CBV response with peak CBV, activated area, and correlation coefficient increasing with ultrasonic dose. Furthermore, by mapping displacement and hemodynamic activation, we found that displacement colocalizes and linearly correlates with CBV increase. The findings presented herein demonstrated that FUS evokes ipsilateral hemodynamic activation in cortical and subcortical depths and the evoked hemodynamic responses colocalized and correlate with FUS-induced displacement. We anticipate that our findings will help consolidate accurate targeting as well as an understanding of how FUS displaces brain tissue and affects cerebral hemodynamics.

8.
Clin Pathol ; 17: 2632010X241263054, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39070952

RESUMEN

The COVID-19 pandemic-led worldwide healthcare crisis necessitates prompt societal, ecological, and medical efforts to stop or reduce the rising number of fatalities. Numerous mRNA based vaccines and vaccines for viral vectors have been licensed for use in emergencies which showed 90% to 95% efficacy in preventing SARS-CoV-2 infection. However, safety issues, vaccine reluctance, and skepticism remain major concerns for making mass vaccination a successful approach to treat COVID-19. Hence, alternative therapeutics is needed for eradicating the global burden of COVID-19 from developed and low-resource countries. Repurposing current medications and drug candidates could be a more viable option for treating SARS-CoV-2 as these therapies have previously passed a number of significant checkpoints for drug development and patient care. Besides vaccines, this review focused on the potential usage of alternative therapeutic agents including antiviral, antiparasitic, and antibacterial drugs, protease inhibitors, neuraminidase inhibitors, and monoclonal antibodies that are currently undergoing preclinical and clinical investigations to assess their effectiveness and safety in the treatment of COVID-19. Among the repurposed drugs, remdesivir is considered as the most promising agent, while favipiravir, molnupiravir, paxlovid, and lopinavir/ritonavir exhibited improved therapeutic effects in terms of elimination of viruses. However, the outcomes of treatment with oseltamivir, umifenovir, disulfiram, teicoplanin, and ivermectin were not significant. It is noteworthy that combining multiple drugs as therapy showcases impressive effectiveness in managing individuals with COVID-19. Tocilizumab is presently employed for the treatment of patients who exhibit COVID-19-related pneumonia. Numerous antiviral drugs such as galidesivir, griffithsin, and thapsigargin are under clinical trials which could be promising for treating COVID-19 individuals with severe symptoms. Supportive treatment for patients of COVID-19 may involve the use of corticosteroids, convalescent plasma, stem cells, pooled antibodies, vitamins, and natural substances. This study provides an updated progress in SARS-CoV-2 medications and a crucial guide for inventing novel interventions against COVID-19.

9.
PLoS One ; 19(8): e0292638, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39088478

RESUMEN

Rapidly increasing antibiotic-resistant bacterial strains in Bangladesh's food and farm animals stem from the excessive and inappropriate use of antibiotics. To assess the prevalence of multi-drug resistant (MDR) Gram-negative bacteria in poultry chicks, we sought to isolate and identify strains carrying antimicrobial resistance genes. Isolation and identification involved biochemical tests, 16S rRNA sequencing, and PCR screening of species-specific genes. MDR patterns were evaluated using CLSI guidelines with seventeen antibiotics across twelve classes. Targeted gene sequences were amplified for the detection of Extended-spectrum ß-Lactamase (ESBL), carbapenem, tetracycline, sulfonamide, and colistin resistance genes. Common isolates, such as Escherichia coli, Klebsiella pneumoniae, Proteus penneri, and Enterobacter hormaechei, exhibited average Multiple Antimicrobial Resistance (MAR) indices of 0.66, 0.76, 0.8, 0.84, and 0.81, 0.76, 0.84, 0.41 for broiler and layer chicken, respectively. Providencia stuartii and Salmonella enterica, exclusive to broiler samples, had MAR indices of 0.82 and 0.84, respectively. Additional isolates Morganella morganii, Aeromonas spp., and Wohlfahrtiimonas chitiniclastica were found in layers (Average MAR indices: 0.73, 0.71, and 0.91). Notably, M. morganii, E. hormaechei and W. chitiniclastica were identified for the first time in Bangladeshi poultry chicken, although their evolution is yet to be understood. In this study, Pan-drug resistance was observed in one P. stuartii (broiler) and one Aeromonas spp. (layer) with a MAR index 1, while all isolates exhibited MAR indices >0.2, indicating MDR. Antimicrobial resistance (AMR) gene screening identified blaTEM, blaSHV, tetA, and sul1 in a majority of the MDR strains. Interestingly, E. coli (lactose positive and negative) and E. hormaechei were exclusively found to possess the tetB gene. In addition, E. coli (lactose negative), Klebsiella pneumoniae, Enterobacter hormaechei, M. morganii, and P. stuartii were observed to carry the colistin-resistant mcr-1 gene, whereas sul2 was detected in E. coli (lactose positive and negative), E. hormaechei, P. stuartii, and P. penneri. These findings emphasize the health risk of our consumers of both broiler and layer chickens as they have turned into a potent reservoir of various AMR gene carrying MDR and Pan-drug resistant bacteria.


Asunto(s)
Antibacterianos , Pollos , Farmacorresistencia Bacteriana Múltiple , Bacterias Gramnegativas , Animales , Bangladesh/epidemiología , Farmacorresistencia Bacteriana Múltiple/genética , Antibacterianos/farmacología , Pollos/microbiología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/genética , Bacterias Gramnegativas/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , ARN Ribosómico 16S/genética , Aves de Corral/microbiología
10.
Mar Pollut Bull ; 194(Pt B): 115302, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37480790

RESUMEN

This study measured 22 metal and metalloid concentrations in Hypnea musciformis from the Bakkhali River estuary and Saint Martin's Island, Bangladesh and determined their potential impact on consumption. Student t-tests showed a significant variation in metal concentrations between the two sampling sites (p < 0.05). Mean concentrations of Co (2.49 ± 0.05 mg/kg), Fe (793.29 ± 11.76 mg/kg), Mn (368.72 ± 4.87 mg/kg), Pb (3.82 ± 0.02 mg/kg), V (11.23 ± 0.20 mg/kg) and Zn (16.60 ± 0.28 mg/kg) were higher in samples collected from the Bakkhali River estuary compared to Saint Martin's Island, while mean concentrations of Ca (484.18 ± 4.68 mg/kg), Cd (2.44 ± 0.03 mg/kg), Mg (2112.70 ± 17.80 mg/kg), Mo (1.57 ± 0.06 mg/kg), Sr (2377.57 ± 29.98 mg/kg), and Ti (258.27 ± 4.62 mg/kg) were higher in samples collected from Saint Martin's Island. Eight heavy metals (Pb, Cd, Zn, Cu, Ni, Mn, Cr, Fe) were used to assess potential health risks for adults, but no potential health risk was detected (HQ value>1). This study reveals positive Se-HBV for H. musciformis collected from both sampling sites, indicating no potential risks involved with Hg toxicity.


Asunto(s)
Metaloides , Algas Marinas , Adulto , Humanos , Bioacumulación , Cadmio , Plomo , Medición de Riesgo
11.
Genomics Inform ; 21(3): e33, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37813629

RESUMEN

Type 2 diabetes mellitus (T2DM) is a multifactorial, polygenic, and metabolically complicated disease. A large number of genes are responsible for the biogenesis of T2DM and calpain10 (CAPN10) is one of them. The association of numerous CAPN10 genetic polymorphisms in the development of T2DM has been widely studied in different populations and noticed inconclusive results. The present study is an attempt to evaluate the plausible association of CAPN10 polymorphism SNP-19 (rs3842570) with T2DM and T2DM-related anthropometric and metabolic traits in the Noakhali region of Bangladesh. This case-control study included 202 T2DM patients and 75 healthy individuals from different places in Noakhali. A significant association (p < 0.05) of SNP-19 with T2DM in co-dominant 2R/3R vs. 3R/3R (odds ratio [OR], 2.7; p=0.0014) and dominant (2R/3R) + (2R/2R) vs. 3R/3R (OR, 2.47; p=0.0011) genetic models was observed. High-risk allele 2R also showed a significant association with T2DM in the allelic model (OR, 1.67; p=0.0109). The genotypic frequency of SNP-19 variants showed consistency with Hardy-Weinberg equilibrium (p > 0.05). Additionally, SNP-19 genetic variants showed potential associations with the anthropometric and metabolic traits of T2DM patients in terms of body mass index, systolic blood pressure, diastolic blood pressure, total cholesterol, and triglycerides. Our approach identifies the 2R/3R genotype of SNP-19 as a significant risk factor for biogenesis of T2DM in the Noakhali population. Furthermore, a large-scale study could be instrumental to correlate this finding in overall Bangladeshi population.

12.
Sci Rep ; 13(1): 4654, 2023 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-36944759

RESUMEN

Back pain is the leading cause of disability worldwide. Its emergence relates not only to the musculoskeletal degeneration biological substrate but also to psychosocial factors; emotional components play a pivotal role. In modern society, people are significantly informed by the Internet; in turn, they contribute social validation to a "successful" digital information subset in a dynamic interplay. The Affective component of medical pages has not been previously investigated, a significant gap in knowledge since they represent a critical biopsychosocial feature. We tested the hypothesis that successful pages related to spine pathology embed a consistent emotional pattern, allowing discrimination from a control group. The pool of web pages related to spine or hip/knee pathology was automatically selected by relevance and popularity and submitted to automated sentiment analysis to generate emotional patterns. Machine Learning (ML) algorithms were trained to predict page original topics from patterns with binary classification. ML showed high discrimination accuracy; disgust emerged as a discriminating emotion. The findings suggest that the digital affective "successful content" (collective consciousness) integrates patients' biopsychosocial ecosystem, with potential implications for the emergence of chronic pain, and the endorsement of health-relevant specific behaviors. Awareness of such effects raises practical and ethical issues for health information providers.


Asunto(s)
Algoritmos , Ecosistema , Humanos , Aprendizaje Automático , Emociones , Dolor de Espalda , Internet
13.
Mol Cell Biochem ; 361(1-2): 97-104, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21959978

RESUMEN

Sulfotransferases catalyze the sulfate conjugation of a wide variety of endogenous and exogenous molecules. Human pathogenic mycobacteria produce numerous sulfated molecules including sulfolipids which are well related to the virulence of several strains. The genome of Mycobacterium avium encodes eight putative sulfotransferases (stf1, stf4-stf10). Among them, STF9 shows higher similarity to human heparan sulfate 3-O-sulfotransferase isoforms than to the bacterial STs. Here, we determined the crystal structure of sulfotransferase STF9 in complex with a sulfate ion and palmitic acid at a resolution of 2.6 Å. STF9 has a spherical structure utilizing the classical sulfotransferase fold. STF9 exclusively possesses three N-terminal α-helices (α1, α2, α3) parallel to the 3'-phosphoadenosine-5'-phosphosulfate (PAPS) binding motif. The sulfate ion binds to the PAPS binding structural motif and the palmitic acid molecule binds in the deep cleft of the predicted substrate binding site suggesting the nature of endogenous acceptor substrate of STF9 resembles palmitic acid. The substrate binding site is covered by a flexible loop which may have involvement in endogenous substrate recognition. Based on the mutational study (Hossain et al., Mol Cell Biochem 350:155-162; 2011) and structural resemblance of STF9-sulfate ion-palmitic acid complex to the hHS3OST3 complex with PAP (3'-phosphoadenosine-5'-phosphate) and an acceptor sugar chain, Glu170 and Arg96 are appeared to be catalytic residues in STF9 sulfuryl transfer mechanism.


Asunto(s)
Proteínas Bacterianas/química , Mycobacterium avium/enzimología , Sulfotransferasas/química , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Sitios de Unión , Dominio Catalítico , Secuencia Conservada , Cristalografía por Rayos X , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Ácido Palmítico/química , Unión Proteica , Sulfatos/química
14.
IEEE Trans Med Imaging ; 41(11): 3099-3115, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35635828

RESUMEN

Mapping of mechanical properties, dependent on the frequency of motion, is relevant in diagnosis, monitoring treatment response, or intra-operative surgical resection planning. While shear wave speeds at different frequencies have been described elsewhere, the effect of frequency on the "on-axis" acoustic radiation force (ARF)-induced displacement has not been previously investigated. Instead of generating single transducer-harmonic motion imaging (ST-HMI)-derived peak-to-peak displacement (P2PD) image at a particular frequency, a novel multi-frequency excitation pulse is proposed to generate P2PD images at 100-1000 Hz simultaneously. The performance of the proposed excitation pulse is compared with the ARFI by imaging 16 different inclusions (Young's moduli of 6, 9, 36, 70 kPa and diameters of 1.6, 2.5, 6.5, and 10.4 mm) embedded in an 18 kPa background. Depending on inclusion size and stiffness, the maximum CNR and contrast were achieved at different frequencies and were always higher than ARFI. The frequency, at which maximum CNR and contrast were achieved, increased with stiffness for fixed inclusion's size and decreased with size for fixed stiffness. In vivo feasibility is tested by imaging a 4T1 breast cancer mouse tumor on Day 6, 12, and 19 post-injection of tumor cells. Similar to phantoms, the CNR of ST-HMI images was higher than ARFI and increased with frequency for the tumor on Day 6. Besides, P2PD at 100-1000 Hz indicated that the tumor became stiffer with respect to the neighboring non-cancerous tissue over time. These results indicate the importance of using a multi-frequency excitation pulse to simultaneously generate displacement at multiple frequencies to better delineate inclusions or tumors.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Neoplasias , Ratones , Animales , Transductores , Módulo de Elasticidad , Fantasmas de Imagen , Movimiento (Física) , Diagnóstico por Imagen de Elasticidad/métodos
15.
IEEE Trans Med Imaging ; 41(6): 1468-1481, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34995184

RESUMEN

Elastic degree of anisotropy (DoA) is a diagnostically relevant biomarker in muscle, kidney, breast, and other organs. Previously, elastic DoA was qualitatively assessed as the ratio of peak displacements (PD) achieved with the long-axis of a spatially asymmetric Acoustic Radiation Force Impulse (ARFI) excitation point spread function (PSF) aligned along versus across the axis of symmetry (AoS) in transversely isotropic materials. However, to better enable longitudinal and cross-sectional analyses, a quantitative measure of elastic DoA is desirable. In this study, qualitative ARFI PD ratios are converted to quantitative DoA, measured as the ratio of longitudinal over transverse shear elastic moduli, using a model empirically derived from Field II and finite element method (FEM) simulations. In silico, the median absolute percent error (MAPE) in ARFI-derived shear moduli ratio (SMR) was 1.75%, and predicted SMRs were robust to variations in transverse shear modulus, Young's moduli ratio, speed of sound, attenuation, density, and ARFI excitation PSF dimension. Further, ARFI-derived SMRs distinguished two materials when the true SMRs of the compared materials differed by as little as 10%. Experimentally, ARFI-derived SMRs linearly correlated with the corresponding ratios measured by Shear Wave Elasticity Imaging (SWEI) in excised pig skeletal muscle ( [Formula: see text], MAPE = 13%) and in pig kidney, in vivo ( [Formula: see text], MAPE = 5.3%). These results demonstrate the feasibility of using the ARFI PD to quantify elastic DoA in biological tissues.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Acústica , Animales , Anisotropía , Estudios Transversales , Módulo de Elasticidad , Diagnóstico por Imagen de Elasticidad/métodos , Porcinos
16.
J Imaging ; 8(4)2022 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-35448225

RESUMEN

Sign language recognition is challenging due to the lack of communication between normal and affected people. Many social and physiological impacts are created due to speaking or hearing disability. A lot of different dimensional techniques have been proposed previously to overcome this gap. A sensor-based smart glove for sign language recognition (SLR) proved helpful to generate data based on various hand movements related to specific signs. A detailed comparative review of all types of available techniques and sensors used for sign language recognition was presented in this article. The focus of this paper was to explore emerging trends and strategies for sign language recognition and to point out deficiencies in existing systems. This paper will act as a guide for other researchers to understand all materials and techniques like flex resistive sensor-based, vision sensor-based, or hybrid system-based technologies used for sign language until now.

17.
Mol Cell Biochem ; 350(1-2): 155-62, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21188624

RESUMEN

Sulfotransferases catalyze the transfer of sulfate group from para-nitrophenyl sulfate (pNPS) or 3'-phosphoadenosine-5'-phosphosulfate (PAPS) onto acceptor molecules in the biosynthesis of sulfate esters. Human pathogenic mycobacteria are known to produce numerous sulfated molecules on their cell surface which have been implicated as important mediators in host-pathogen interactions. The open reading frame stf9, a predicted homologue of sulfotransferase in the Mycobacterium avium genomic data, was cloned and over expressed in Escherichia coli. The recombinant STF9 conserved the characteristic PAPS binding motif of sulfotransferase and was purified as a 44 kDa soluble protein which exhibited transfer of sulfate group from pNPS (K (m) 1.34 mM, V (max) 7.56 nmol/min/mg) onto 3'-phosphoadenosine-5'-phosphate (K (m) 0.24 mM, V (max) 10.36 nmol/min/mg). The recombinant STF9 protein was also capable of transferring sulfate group from PAPS onto certain acceptor substrates in E. coli, and showed binding affinity to the PAP-agarose resin, supporting the sulfotransferase activity of the recombinant STF9 protein. This is the first report of molecular evidence for sulfotransferase activity of a protein from M. avium. Mutation of Arg96 to Ala and Glu170 to Ala abolishes sulfotransferase activity, indicating the importance of Arg96 and Glu170 in STF9 activity catalysis.


Asunto(s)
Mycobacterium avium/genética , Sulfotransferasas/genética , Sulfotransferasas/fisiología , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Dominio Catalítico/genética , Clonación Molecular , Biología Computacional , Predicción , Perfilación de la Expresión Génica , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Mycobacterium avium/enzimología , Mycobacterium avium/metabolismo , Sulfotransferasas/química , Sulfotransferasas/aislamiento & purificación
18.
IEEE Trans Med Imaging ; 40(5): 1390-1404, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33523806

RESUMEN

Harmonic motion imaging (HMI) interrogates the mechanical properties of tissues by simultaneously generating and tracking harmonic oscillation using focused ultrasound and imaging transducers, respectively. Instead of using two transducers, the objective of this work is to develop a single transducer HMI (ST-HMI) to both generate and track harmonic motion at "on-axis" to the force for facilitating data acquisition. In ST-HMI, the amplitude-modulated force was generated by modulating excitation pulse duration and tracking of motion was performed by transmitting tracking pulses interleaved between excitation pulses. The feasibility of ST-HMI was performed by imaging two elastic phantoms with three inclusions (N = 6) and comparing it with acoustic radiation force impulse (ARFI) imaging, in vivo longitudinal monitoring of 4T1, orthotropic breast cancer mice (N = 4), and patients (N = 3) with breast masses in vivo. Six inclusions with Young's moduli of 8, 10, 15, 20, 40, and 60 kPa were embedded in a 5 kPa background. The ST-HMI-derived peak-to-peak displacement (P2PD) successfully detected all inclusions with [Formula: see text] of the linear regression between the P2PD ratio of background to inclusion versus Young's moduli ratio of inclusion to background. The contrasts of 10 and 15 kPa inclusions were higher in ST-HMI than ARFI-derived images. In the mouse study, the median P2PD ratio of tumor to non-cancerous tissues was 3.0, 5.1, 6.1, and 7.7 at 1, 2, 3, and 4 weeks post-injection of the tumor cells, respectively. In the clinical study, ST-HMI detected breast masses including fibroadenoma, pseudo angiomatous stromal hyperplasia, and invasive ductal carcinoma with a P2PD ratio of 1.37, 1.61, and 1.78, respectively. These results indicate that ST-HMI can assess the mechanical properties of tissues via generation and tracking of harmonic motion "on-axis" to the ARF. This study is the first step towards translating ST-HMI in clinics.


Asunto(s)
Neoplasias de la Mama , Diagnóstico por Imagen de Elasticidad , Animales , Neoplasias de la Mama/diagnóstico por imagen , Estudios de Factibilidad , Femenino , Humanos , Ratones , Fantasmas de Imagen , Sujetos de Investigación , Transductores
19.
Artículo en Inglés | MEDLINE | ID: mdl-32833634

RESUMEN

Degree of anisotropy (DoA) of mechanical properties has been assessed as the ratio of acoustic radiation force impulse (ARFI)-induced peak displacements (PDs) achieved using spatially asymmetric point spread functions (PSFs) that are rotated 90° to each other. Such PSF rotation has been achieved by manually rotating a linear array transducer, but manual rotation is cumbersome and prone to misalignment errors and higher variability in measurements. The purpose of this work is to evaluate the feasibility of electronic PSF rotation using a three-row transducer, which will reduce variability in DoA assessment. A Siemens 9L4, with 3×192 elements, was simulated in Field II to generate spatially asymmetric ARFI PSFs that were electronically rotated 63° from each other. Then, using the finite element method (FEM), PD due to the ARFI excitation PSFs in 42 elastic, incompressible, transversely isotropic (TI) materials with shear moduli ratios of 1.0-6.0 were modeled. Finally, the ratio of PDs achieved using the two rotated PSFs was evaluated to assess elastic DoA. DoA increased with increasing shear moduli ratios and distinguished materials with 17% or greater difference in shear moduli ratios (Wilcoxon, ). Experimentally, the ratio of PDs achieved using ARFI PSF rotated 63° from each other distinguished the biceps femoris muscle from two pigs, which had median shear moduli ratios of 4.25 and 3.15 as assessed by shear wave elasticity imaging (SWEI). These results suggest that ARFI-based DoA assessment can be achieved without manual transducer rotation using a three-row transducer capable of electronically rotating PSFs by 63°. It is expected that electronic PSF rotation will facilitate data acquisitions and improve the reproducibility of elastic anisotropy assessments.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Animales , Anisotropía , Simulación por Computador , Electrónica , Reproducibilidad de los Resultados , Rotación , Porcinos , Transductores
20.
Heliyon ; 7(8): e07851, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34471717

RESUMEN

Diabetes is currently a growing concern of the age. Prevention and treatment of diabetes is a global health priority. Adiponectin is an adipocyte derived protein hormone that enhances insulin sensitivity and ameliorates diabetes by enhancing fatty acid oxidation and glucose uptake in skeletal muscle and reducing glucose production in the liver. Low serum adiponectin concentrations are associated with diabetes, central obesity, insulin resistance and metabolic syndrome. Adiponectin gene is located on chromosome 3q27, where a locus of susceptibility to diabetes was mapped. Several cross-sectional studies showed that single nucleotide polymorphisms (SNPs) in adiponectin gene (ADIPOQ) were associated with diabetes. SNPs in ADIPOQ help in assessing the association of common variants with levels of adiponectin and the risk of diabetes. Two common SNPs, rs2241766 and rs1501299, have been linked significantly to type 1 diabetes mellitus which endow the world with a block of haplotypes. Experimental evidences also suggest that rs1501299, rs2241766, rs266729, rs17366743, rs17300539, rs182052, rs822396, rs17846866, rs3774261 and rs822393 are significantly associated with type 2 diabetes mellitus which is the predominant form of the disease. In addition, rs2241766 and rs266729 are extensively associated with gestational diabetes, a condition that develops in women during pregnancy. Therefore not a particular single mutation but a number of SNPs in adiponectin gene could be a risk factor for developing diabetes among the individuals worldwide. This study firmly suggests that adiponectin plays a crucial role in the pathogenesis of type 1, type 2 and gestational diabetes mellitus.

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