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1.
Artículo en Inglés | MEDLINE | ID: mdl-39007979

RESUMEN

The detection of uranium in drinking water has ignited concerns among the public, regulators, and policymakers, particularly as around 1% of the 55,554 water samples in India have shown uranium levels surpassing the 60 µg/l guideline established by the Atomic Energy Regulatory Board (AERB) based on radiological toxicity. Further, the Bureau of Indian Standard (BIS), has given a limit of 30 µg/l, which is derived from World Health Organization (WHO) guidelines. Besides the chemical and radiological aspects associated with uranium, factors such as technological constraints in water purification, waste management, environmental factors, and socio-economic conditions significantly influence these guideline values, which are often overlooked. This manuscript explores the variations in approaches for establishing guideline values and highlights the uncertainties arising from dependence on various variables such as intake and usage patterns, inter- and intra-species distinctions, and epidemiological data. A critical analysis indicates that adherence to global guidelines may result in some undesirable environmental issues. By considering factors such as population dynamics, socio-economic conditions, and geological influences, we suggest that limit of 60 µg/l for uranium in drinking water is appropriate for India.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38992473

RESUMEN

BACKGROUND: The discriminatory and racist policy of historical redlining in the United States (U.S.) during the 1930s played a role in perpetuating contemporary environmental health disparities. OBJECTIVE: Our objectives were to determine associations between home and school pollutant exposure (fine particulate matter (PM2.5), nitrogen dioxide (NO2)) and respiratory outcomes (Composite Asthma Severity Index (CASI), lung function) among school-aged children with asthma and examine whether associations differed between children who resided and/or attended school in historically redlined compared to non-redlined neighborhoods. METHODS: Children ages 6 to 17 with moderate-to-severe asthma (N=240) from 9 U.S. cities were included. Combined home and school exposure to PM2.5 and NO2 was calculated based on geospatially assessed monthly averaged outdoor pollutant concentrations. Repeated measures of CASI and lung function were collected. RESULTS: Overall, 37.5% of children resided and/or attended schools in historically redlined neighborhoods. Children in historically redlined neighborhoods had greater exposure to NO2 (median: 15.4 vs 12.1 ppb) and closer distance to a highway (median: 0.86 vs 1.23 km), compared to those in non-redlined neighborhoods (p<0.01). Overall, PM2.5 was not associated with asthma severity or lung function. However, among children in redlined neighborhoods, higher PM2.5 was associated with worse asthma severity (p<0.005). No association was observed between pollutants and lung function or asthma severity among children in non-redlined neighborhoods (p>0.005). CONCLUSIONS: Our findings highlight the significance of historical redlining and current environmental health disparities among school-aged children with asthma, specifically, the environmental injustice of PM2.5 exposure and its associations with respiratory health.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38988306

RESUMEN

OBJECTIVE: The Risk Analysis Index (RAI) score is a screening tool to assess patient frailty. It has been shown to be predictive of postoperative outcomes and mortality in orthopedic, urologic, and neurosurgical patient populations. We sought to evaluate the predictive ability of RAI score for surgical outcomes in an otolaryngology patient population. STUDY DESIGN: Retrospective study. SETTING: Academic tertiary medical center. METHODS: A retrospective study was conducted of adult patients undergoing otolaryngology surgery at a tertiary medical care center over 21 months. Patients were sent electronic RAI survey questionnaires via direct messaging, which was completed prior to surgery. Endpoint data were analyzed, including demographics, RAI score, and patient outcome data. Univariate analysis, ROC curves, and predictive modeling were utilized. RESULTS: A total of 517 patients responded to the RAI questionnaire, resulting in a 59.6% response rate. Mean RAI score was 21.38 ± 11.83. Higher RAI scores were associated with increased 30-day readmissions (P < .0015), postoperative complications (P < .001), hospital length of stay (P < .001), and discharge with home health (P < .001). Predictive models for RAI score and postoperative outcomes were created, and a cutoff score of RAI = 30 was established to identify frail patients. CONCLUSION: We evaluated if RAI scoring predicted postoperative complications in an otolaryngology patient population. Increased RAI score is significantly associated with poorer surgical outcomes, including increased hospital length of stay, 30-day readmissions, and postoperative complications. We propose a predictive model with suggested RAI cutoff scoring for use in the otolaryngology surgical population.

4.
Cureus ; 16(6): e61582, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38962607

RESUMEN

STUDY OBJECTIVE:  Epidural blood patches (EBPs) are frequently performed in children with cerebral palsy (CP) to manage post-dural puncture headache (PDPH) due to cerebrospinal fluid (CSF) leak after intrathecal baclofen pump (ITBP) placement or replacement procedures. The purpose of our study was to review the incidence and management of CSF leak following ITBP placement or replacement procedures in children with CP. The study was a retrospective review of 245 patients representing 310 surgical cases of baclofen pump insertion (n=141) or reinsertion (n=169) conducted at a 125-bed children's hospital with prominent specialty orthopedics surgical cases. MEASUREMENTS:  Demographic and clinical information was obtained from the anesthesia pain service database on all new ITBP placement and subsequent replacements over an eight-year period. MAIN RESULTS:  The overall incidence of CSF leak in our population was 16% (50 of 310) and 18% (25 of 141) with a new ITBP placement. Children with diplegia were associated with a threefold risk of developing CSF leak. Of patients who developed CSF leak (n=50), 68% (n=34) were successfully treated conservatively, while 32% (n=16) required EBPs. EBPs were successful in 87.5% (14 of 16) of patients at relieving PDPH on the first attempt.  Conclusions: CSF leak is a known problem after ITBP placement and replacement. Most patients were successfully treated with conservative management and EBPs were successful in patients failing conservative therapy. Diagnosing PDPH in non-verbal patients can be challenging.

5.
Laryngoscope ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949061

RESUMEN

INTRODUCTION: Myasthenia gravis (MG) is an autoimmune disease that affects the neuromuscular junction. MG patients may present de novo with primary otolaryngology complaints, including swallowing dysfunction. This study describes a range of unique presentations and rare diagnostic serologies, which have not previously been fully described. METHODS: A retrospective review was performed of all patients presenting with primary symptom of dysphagia and subsequently diagnosed with MG. Data collected included demographics, clinical presentation, swallow studies, serology, imaging, treatment, and response. RESULTS: Five patients met the inclusion criteria. Four endorsed dysphagia as primary complaint and one endorsed dysphagia and dysphonia. All patients underwent in-office swallow evaluations that showed vallecular or pyriform sinus residue. Three patients completed modified barium swallow studies that showed pharyngeal weakness and epiglottic dysfunction in all, and upper esophageal sphincter dysfunction in two. One patient with additional symptom of dyspnea was admitted and found to be in myasthenic crisis. Upon serologic evaluation, three patients were positive for acetylcholine receptor (AChR) antibodies only, one for muscle-specific-kinase (MuSK) antibodies only, and one for low density lipoprotein receptor-related protein 4 (LRP4) antibodies only. All patients received neurology evaluation and were treated with steroids, pyridostigmine, plasma exchange, or rituximab. In three patients with over 1 year follow-up, symptoms were significantly improved or resolved. CONCLUSION: MG is an important differential diagnosis in patients with unexplained pharyngeal dysphagia. While workup can include AChR antibody screening, in seronegative patients with persistent symptoms, additional testing for MuSK and LRP4 may lead to diagnosis and effective treatment. LEVEL OF EVIDENCE: Level 4 Laryngoscope, 2024.

6.
BMJ Open ; 14(7): e085854, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969384

RESUMEN

INTRODUCTION: At least 10% of hospital admissions in high-income countries, including Australia, are associated with patient safety incidents, which contribute to patient harm ('adverse events'). When a patient is seriously harmed, an investigation or review is undertaken to reduce the risk of further incidents occurring. Despite 20 years of investigations into adverse events in healthcare, few evaluations provide evidence of their quality and effectiveness in reducing preventable harm.This study aims to develop consistent, informed and robust best practice guidance, at state and national levels, that will improve the response, learning and health system improvements arising from adverse events. METHODS AND ANALYSIS: The setting will be healthcare organisations in Australian public health systems in the states of New South Wales, Queensland, Victoria and the Australian Capital Territory. We will apply a multistage mixed-methods research design with evaluation and in-situ feasibility testing. This will include literature reviews (stage 1), an assessment of the quality of 300 adverse event investigation reports from participating hospitals (stage 2), and a policy/procedure document review from participating hospitals (stage 3) as well as focus groups and interviews on perspectives and experiences of investigations with healthcare staff and consumers (stage 4). After triangulating results from stages 1-4, we will then codesign tools and guidance for the conduct of investigations with staff and consumers (stage 5) and conduct feasibility testing on the guidance (stage 6). Participants will include healthcare safety systems policymakers and staff (n=120-255) who commission, undertake or review investigations and consumers (n=20-32) who have been impacted by adverse events. ETHICS AND DISSEMINATION: Ethics approval has been granted by the Northern Sydney Local Health District Human Research Ethics Committee (2023/ETH02007 and 2023/ETH02341).The research findings will be incorporated into best practice guidance, published in international and national journals and disseminated through conferences.


Asunto(s)
Seguridad del Paciente , Proyectos de Investigación , Humanos , Australia , Daño del Paciente/prevención & control , Mejoramiento de la Calidad , Errores Médicos/prevención & control , Grupos Focales , Atención a la Salud
7.
J Cancer Res Ther ; 20(3): 817-821, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-39023588

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is a disease of the older population in developed countries where the incidence among the young is rising despite the decline in the overall incidence. Contrary to this, in India, which is a low-incidence country for CRCs, the incidence among all age groups including the young is rising. This study aimed at describing the clinico-demographic profile of young CRC cases and the epidemiological trend of the proportion of young cases from 2014 to 2021 in a tertiary cancer center in Eastern India. METHODS: This retrospective observational study was conducted at Department of Radiation Oncology, State Cancer Institute, IGIMS Patna, India a prominent tertiary cancer care center of Bihar. All histopathologically confirmed CRC cases in the 0-39 years age group were considered young and evaluated for the clinical, demographic profile as well as yearly trends in proportion out of total CRC cases. Microsoft Excel (2021) was used for statistical analysis. A P value of 0.05 was considered significant. RESULTS: Young colorectal (less than 40 years) patients constituted a third (n = 344, 33.4%) of total colorectal (n = 1028) cases. The median age among the young CRC cases was 30 years (range: 12 to 39 years). Rectum was the most common subsite noted (n = 255,74.1%) among this group of young patients. The most commonly encountered stage of the disease was III (n = 107, 31.1%) and chemotherapy was the most common treatment offered (n = 153, 44.5%). The proportion of young (0-39 years) CRC cases ranged between 29.4 and 37.4 (mean 33.5 ± 2.77, P value = 0.725) over the calendar years of the study period. CONCLUSION: The proportion of young (<40 years of age) cases out of total CRC cases in our study is higher than that in developed countries. However, the trends of this proportion have been consistent over the study period, i.e., from 2014 to 2021 without any significant change in our hospital-based cancer registry. Rectal cancer affected nearly three out of every four CRC patients in this age group. More advanced disease at presentation emphasizes the need for measures of screening, early diagnosis, and adequate infrastructure for treatment.


Asunto(s)
Neoplasias Colorrectales , Humanos , India/epidemiología , Estudios Retrospectivos , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/patología , Masculino , Femenino , Adulto , Adulto Joven , Adolescente , Niño , Incidencia , Preescolar , Lactante , Recién Nacido , Factores de Edad
8.
Prog Cardiovasc Dis ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38925255

RESUMEN

Cardiovascular magnetic resonance (CMR) imaging is the gold standard test for myocardial tissue characterization and chamber volumetric and functional evaluation. However, manual CMR analysis can be time-consuming and is subject to intra- and inter-observer variability. Artificial intelligence (AI) is a field that permits automated task performance through the identification of high-level and complex data relationships. In this review, we review the rapidly growing role of AI in CMR, including image acquisition, sequence prescription, artifact detection, reconstruction, segmentation, and data reporting and analysis including quantification of volumes, function, myocardial infarction (MI) and scar detection, and prediction of outcomes. We conclude with a discussion of the emerging challenges to widespread adoption and solutions that will allow for successful, broader uptake of this powerful technology.

9.
JACC Adv ; 3(2): 100815, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38939394

RESUMEN

With a growing body of evidence that now links environmental pollution to adverse cardiovascular disease (CVD) outcomes, pollution has emerged as an important risk factor for CVD. There is thus an urgent need to better understand the role of pollution in CVD, key pathophysiological mechanisms, and to raise awareness among health care providers, the scientific community, the general population, and regulatory authorities about the CV impact of pollution and strategies to reduce it. This article is part 2 of a 2-part state-of-the-art review on the topic of pollution and CVD-herein we discuss major environmental pollutants and their effects on CVD, highlighting pathophysiological mechanisms, and strategies to reduce CVD risk.

10.
JACC Adv ; 3(2): 100805, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38939391

RESUMEN

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality worldwide. Over the past 50 years, there has been a substantial decline in the incidence of CVD and related mortality in high-income countries, largely due to the mitigation of modifiable risk factors such as smoking, hypertension, and diabetes. However, a significant burden of CVD remains in low- to middle-income countries, despite their lower prevalence of traditional risk factors; other environmental factors, particularly pollution, play a significant role in this attributable risk. Mounting evidence underscores a strong association between pollution and adverse health effects, including CVD. This article is part 1 of a 2-part state-of-the-art review and discusses air pollution and its adverse effects on CVD, highlighting pathophysiological mechanisms and methods to reduce air pollution and exposure to these pollutants.

11.
Biomedicines ; 12(6)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38927436

RESUMEN

Lipoprotein(a) is a low-density-lipoprotein-like particle that consists of apolipoprotein(a) bound to apolipoprotein(b). It has emerged as an established causal risk factor for atherosclerotic cardiovascular disease, stroke, and aortic valve stenosis through multifactorial pathogenic mechanisms that include inflammation, atherogenesis, and thrombosis. Despite an estimated 20% of the global population having elevated lipoprotein(a) levels, testing remains underutilized due to poor awareness and a historical lack of effective and safe therapies. Although lipoprotein(a) has a strong association with coronary artery disease and cerebrovascular disease, its relationship with peripheral artery disease is less well established. In this article, we review the epidemiology, biology, and pathogenesis of lipoprotein(a) as it relates to peripheral artery disease. We also discuss emerging treatment options to help mitigate major adverse cardiac and limb events in this population.

12.
ACS Appl Mater Interfaces ; 16(26): 33752-33762, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38902888

RESUMEN

The sensitivity of ferroelectric domain walls to external stimuli makes them functional entities in nanoelectronic devices. Specifically, optically driven domain reconfiguration with in-plane polarization is advantageous and thus is highly sought. Here, we show the existence of in-plane polarized subdomains imitating a single domain state and reversible optical control of its domain wall movement in a single-crystal of ferroelectric BaTiO3. Similar optical control in the domain configuration of nonpolar ferroelastic material indicates that long-range ferroelectric polarization is not essential for the optical control of domain wall movement. Instead, flexoelectricity is found to be an essential ingredient for the optical control of the domain configuration, and hence, ferroelastic materials would be another possible candidate for nanoelectronic device applications.

13.
Cureus ; 16(5): e59723, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38854196

RESUMEN

BACKGROUND: Vertebral body tethering (VBT) requires a thoracoscopic approach to visualize the vertebral bodies. Lung collapse and re-expansion have the potential to cause acute lung injury, resulting in increased oxygen and ventilation requirements. AIMS: We compared the intraoperative ventilator management, intra- and postoperative blood gas determinations, and hospital stay information between adolescents undergoing unilateral versus bilateral lung isolation for vertebral body tethering. METHODS:  A study cohort of 132 propensity-matched cases (66 unilateral and 66 bilateral) was derived from 351 consecutive VBT cases. Patient demographic information, case information, fluid administration, ventilatory settings data, blood gas parameters, and complete blood count and differential data were entered into a datasheet. Derived parameters included values calculated from the alveolar gas equation to develop an oxygen cascade and measures of inflammatory response. Chi-square was used for categorical data, and independent samples and t-tests were used for continuous data. RESULTS: The double lung isolation group required higher peak inspiratory pressures (SL 29±5 vs. DL 31±5, p=0.026), resulting in higher tidal volume (SL 246±63 vs. DL 334±101, p<0.001) and tidal volume per kg (SL 5.6±1.4 vs. DL 6.9±2, p<0.001) as compared to the single lung group. The double lung group required a higher partial pressure of inspired and alveolar oxygen as well as a higher alveolar to arterial oxygen tension gradient (SL 417±126 vs. DL 485±96, p=0.001) to achieve optimal arterial oxygen tension. Patients with double lung isolation had similar intensive care lengths of stay but a longer hospital stay than single lung isolation patients. CONCLUSION: Patients undergoing double lung isolation required greater ventilatory support and had more evidence of acute lung injury, as evidenced by a higher postoperative alveolar to arterial oxygen gradient; however, these healthy adolescents tolerated the procedure well and only differed in the hospital length of stay by a day.

14.
J Clin Med ; 13(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38929986

RESUMEN

Cardiovascular disease (CVD), particularly coronary heart disease (CHD), is the leading cause of death in the US, with a high economic impact. Coronary artery calcium (CAC) is a known marker for CHD and a useful tool for estimating the risk of atherosclerotic cardiovascular disease (ASCVD). Although CACS is recommended for informing the decision to initiate statin therapy, the current standard requires a dedicated CT protocol, which is time-intensive and contributes to radiation exposure. Non-dedicated CT protocols can be taken advantage of to visualize calcium and reduce overall cost and radiation exposure; however, they mainly provide visual estimates of coronary calcium and have disadvantages such as motion artifacts. Artificial intelligence is a growing field involving software that independently performs human-level tasks, and is well suited for improving CACS efficiency and repurposing non-dedicated CT for calcium scoring. We present a review of the current studies on automated CACS across various CT protocols and discuss consideration points in clinical application and some barriers to implementation.

15.
Pharmaceuticals (Basel) ; 17(6)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38931375

RESUMEN

BACKGROUND: Literature on the preferred anticoagulant for treating left ventricular thrombus (LVT) is lacking. Thus, our objective was to compare the efficacy of DOACs versus warfarin in treating LVT. METHODS: Databases were searched for RCTs and adjusted observational studies that compared DOAC versus warfarin through March 2024. The primary efficacy outcomes of interest were LVT resolution, systemic embolism, composite of stroke, and TIA. The primary safety outcomes encompassed all-cause mortality and bleeding events. RESULTS: Our meta-analysis including 31 studies demonstrated that DOAC use was associated with higher odds of thrombus resolution (OR: 1.08, 95% CI: 0.86-1.31, p: 0.46). A statistically significant reduction in the risk of stroke/TIA was observed in the DOAC group versus the warfarin group (OR: 0.65, 95% CI: 0.48-0.89, p: 0.007). Furthermore, statistically significant reduced risks of all-cause mortality (OR: 0.68, 95% CI: 0.47-0.98, p: 0.04) and bleeding events (OR: 0.70, 95% CI: 0.55-0.89, p: 0.004) were observed with DOAC use as compared to warfarin use. CONCLUSION: Compared to VKAs, DOACs are noninferior as the anticoagulant of choice for LVT treatment. However, further studies are warranted to confirm these findings.

16.
EMBO J ; 43(14): 2979-3008, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38839991

RESUMEN

Lipid-protein interactions play a multitude of essential roles in membrane homeostasis. Mitochondrial membranes have a unique lipid-protein environment that ensures bioenergetic efficiency. Cardiolipin (CL), the signature mitochondrial lipid, plays multiple roles in promoting oxidative phosphorylation (OXPHOS). In the inner mitochondrial membrane, the ADP/ATP carrier (AAC in yeast; adenine nucleotide translocator, ANT in mammals) exchanges ADP and ATP, enabling OXPHOS. AAC/ANT contains three tightly bound CLs, and these interactions are evolutionarily conserved. Here, we investigated the role of these buried CLs in AAC/ANT using a combination of biochemical approaches, native mass spectrometry, and molecular dynamics simulations. We introduced negatively charged mutations into each CL-binding site of yeast Aac2 and established experimentally that the mutations disrupted the CL interactions. While all mutations destabilized Aac2 tertiary structure, transport activity was impaired in a binding site-specific manner. Additionally, we determined that a disease-associated missense mutation in one CL-binding site in human ANT1 compromised its structure and transport activity, resulting in OXPHOS defects. Our findings highlight the conserved significance of CL in AAC/ANT structure and function, directly tied to specific lipid-protein interactions.


Asunto(s)
Cardiolipinas , Translocasas Mitocondriales de ADP y ATP , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Cardiolipinas/metabolismo , Sitios de Unión , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Humanos , Translocasas Mitocondriales de ADP y ATP/metabolismo , Translocasas Mitocondriales de ADP y ATP/genética , Translocasas Mitocondriales de ADP y ATP/química , Fosforilación Oxidativa , Translocador 1 del Nucleótido Adenina/metabolismo , Translocador 1 del Nucleótido Adenina/genética , Simulación de Dinámica Molecular , Unión Proteica , Mitocondrias/metabolismo , Mitocondrias/genética , Membranas Mitocondriales/metabolismo , Mutación , Mutación Missense
17.
Plant Signal Behav ; 19(1): 2365572, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38904257

RESUMEN

G protein-coupled receptors (GPCRs) constitute the largest family of transmembrane proteins in metazoans that mediate the regulation of various physiological responses to discrete ligands through heterotrimeric G protein subunits. The existence of GPCRs in plant is contentious, but their comparable crucial role in various signaling pathways necessitates the identification of novel remote GPCR-like proteins that essentially interact with the plant G protein α subunit and facilitate the transduction of various stimuli. In this study, we identified three putative GPCR-like proteins (OsGPCRLPs) (LOC_Os06g09930.1, LOC_Os04g36630.1, and LOC_Os01g54784.1) in the rice proteome using a stringent bioinformatics workflow. The identified OsGPCRLPs exhibited a canonical GPCR 'type I' 7TM topology, patterns, and biologically significant sites for membrane anchorage and desensitization. Cluster-based interactome mapping revealed that the identified proteins interact with the G protein α subunit which is a characteristic feature of GPCRs. Computational results showing the interaction of identified GPCR-like proteins with G protein α subunit and its further validation by the membrane yeast-two-hybrid assay strongly suggest the presence of GPCR-like 7TM proteins in the rice proteome. The absence of a regulator of G protein signaling (RGS) box in the C- terminal domain, and the presence of signature motifs of canonical GPCR in the identified OsGPCRLPs strongly suggest that the rice proteome contains GPCR-like proteins that might be involved in signal transduction.


Asunto(s)
Oryza , Proteínas de Plantas , Proteoma , Receptores Acoplados a Proteínas G , Oryza/metabolismo , Oryza/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Proteoma/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética
18.
Magn Reson Med ; 92(4): 1338-1347, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38704666

RESUMEN

PURPOSE: Localized shimming in single-voxel MRS often results in large B0 inhomogeneity outside the volume-of-interest. This causes unacceptable degradation in motion navigator images. Switching back and forth between whole-brain shim and localized shim is possible for linear shims, but not for higher-order shims. Here we propose motion navigators largely insensitive to B0 inhomogeneity for prospective motion-corrected MRS with localized higher-order shimming. METHODS: A recent fast high-resolution motion navigator based on spiral-in/out k-space trajectories and multislice-to-volume registration was modified by splitting the readout into multiple shot interleaves which shortened the echo time and reduced the effect of B0 inhomogeneity. The performance of motion correction was assessed in healthy subjects in the prefrontal cortex using a sLASER sequence at 3T (N = 5) and 7T (N = 5). RESULTS: With multiple spatial interleaves, excellent quality navigator images were acquired in the whole brain in spite of large B0 inhomogeneity outside the MRS voxel. The total duration of the navigator in sLASER remained relatively short even with multiple shots (3T: 10 spatial interleaves 94 ms per slice; 7T: 15 spatial interleaves 103 ms per slice). Prospective motion correction using the multi-shot navigators yielded comparable spectral quality (water linewidth and metabolite SNR) with and without subject motion. CONCLUSION: B0-insensitive motion navigators enable prospective motion correction for MRS with all first- and second-order shims adjusted in the MRS voxel, providing optimal spectral linewidth.


Asunto(s)
Algoritmos , Movimiento (Física) , Humanos , Espectroscopía de Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Artefactos , Masculino , Adulto , Femenino , Reproducibilidad de los Resultados , Corteza Prefrontal/diagnóstico por imagen , Sensibilidad y Especificidad
19.
Int J Biol Macromol ; 271(Pt 2): 132374, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38754669

RESUMEN

The controlled delivery of the desired bioactive molecules is required to achieve the maximum therapeutic effects with minimum side effects. Biopolymer-based hydrogels are ideal platforms for delivering the desired molecules owing to their superior biocompatibility, biodegradability, and low-immune response. However, the prolonged delivery of the drugs through biopolymer-based hydrogels is restricted due to their weak mechanical stability. We developed mechanically tough and biocompatible hydrogels to address these limitations using carboxymethyl chitosan, sodium alginate, and nanocellulose for sustained drug delivery. The hydrogels were cross-linked through calcium ions to enhance their mechanical strength. Nanocellulose-added hydrogels exhibited improved mechanical strength (Young's modulus; 23.36 â†’ 30.7 kPa, Toughness; 1.39 â†’ 5.65 MJm-3) than pure hydrogels. The composite hydrogels demonstrated increased recovery potential (66.9 â†’ 84.5 %) due to the rapid reformation of damaged polymeric networks. The hydrogels were stable in an aqueous medium and demonstrated reduced swelling potential. The hydrogels have no adverse effects on embryonic murine fibroblast (3 T3), showing their biocompatibility. No bacterial growth was observed in hydrogels-treated groups, indicating their antibacterial characteristics. The sustained drug released was observed from nanocellulose-assisted hydrogel scaffolds compared to the pure polymer hydrogel scaffold. Thus, hydrogels have potential and could be used as a sustained drug carrier.


Asunto(s)
Celulosa , Quitosano , Hidrogeles , Celulosa/química , Celulosa/análogos & derivados , Hidrogeles/química , Ratones , Animales , Quitosano/química , Quitosano/análogos & derivados , Sistemas de Liberación de Medicamentos , Alginatos/química , Materiales Biocompatibles/química , Liberación de Fármacos , Preparaciones de Acción Retardada , Portadores de Fármacos/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/administración & dosificación , Nanopartículas/química
20.
JAMA Cardiol ; 9(6): 582-583, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691373

RESUMEN

A woman in her mid-60s with a history of paroxysmal atrial fibrillation and hypertension presents with 3 days of nausea, vomiting, and diarrhea. What would you do next?


Asunto(s)
Diarrea , Electrocardiografía , Humanos , Femenino , Diarrea/etiología , Persona de Mediana Edad , Taquicardia/etiología , Taquicardia/diagnóstico
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