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3.
Cureus ; 16(9): e68562, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39238922

RESUMEN

This case report describes a patient who presented with concern for a closed-loop small bowel obstruction (SBO). During exploratory laparotomy, an area of ischemic bowel due to closed loop obstruction was resected, along with an incidentally discovered inflamed-appearing Meckel's diverticulum (MD). The resected specimen contained a well-differentiated carcinoid tumor of benign behavior with a maximum diameter of 0.6 cm, which invaded the submucosal layer (pT1b and pN0). Over the last several years, there has been a debate with little consensus regarding the proper surgical management in the case of an asymptomatic MD that is discovered incidentally during abdominal exploration. The intention of sharing this case is to underline the importance of the decision-making process in treating patients with this intraabdominal pathologic condition found incidentally at the time of surgery.

4.
Artículo en Inglés | MEDLINE | ID: mdl-39146219

RESUMEN

OBJECTIVE: Pulmonary CT angiography (CTA) to detect pulmonary emboli can be performed using conventional dual-source CT with single-energy acquisition at high-pitch (high-pitch conventional CT), which minimizes motion artifacts, or routine-pitch, dual-energy acquisitions (routine-pitch conventional DECT), which maximize iodine signal. We compared iodine signal, radiation dose, and motion artifacts of pulmonary CTA between these conventional CT modalities and dual-source photon-counting detector CT with high-pitch, multienergy acquisitions (high-pitch photon-counting CT). METHODS: Consecutive clinically indicated pulmonary CTA exams were collected. CT number/noise was measured from the main to right lower lobe segmental pulmonary arteries using 120 kV threshold low, 120 kV, and mixed kV (0.6 linear blend) images. Three radiologists reviewed anonymized, randomized exams, rating them using a 4- or 5-point Likert scale (1 = worst, and 4/5 = best) for contrast enhancement in pulmonary arteries, motion artifacts in aortic root to subsegmental pulmonary arteries, lung image quality; pulmonary blood volume (PBV) map image quality (for multienergy or dual-energy exams), and contribution to reader confidence. RESULTS: One hundred fifty patients underwent high-pitch photon-counting CT (n = 50), high-pitch conventional CT (n = 50), and routine-pitch conventional DECT (n = 50). High-pitch photon-counting CT had lower radiation dose (CTDIvol: 8.1 ± 2.5 vs 9.6 ± 6.8 and 16.2 ± 8.5 mGy, respectively; P < 0.001), and routine-pitch conventional DECT had significantly less contrast (P < 0.009). CT number and CNR measurements were significantly greater at high-pitch photon-counting CT (P < 0.001). Across readers, high-pitch photon-counting CT demonstrated significantly higher subjective contrast enhancement in the pulmonary arteries compared to the other modalities (4.7 ± 0.6 vs 4.4 ± 0.7 vs 4.3 ± 0.7; P = 0.011) and lung image quality (3.4 ± 0.5 vs 3.1 ± 0.5 vs 3.1 ± 0.5; P = 0.013). High-pitch photon-counting CT and high-pitch conventional CT had fewer motion artifacts at all levels compared to DECT (P < 0.001). High-pitch photon-counting CT PBV maps had superior image quality (P < 0.001) and contribution to reader confidence (P < 0.001) compared to routine-pitch conventional DECT. CONCLUSION: High-pitch photon-counting pulmonary CTA demonstrated higher contrast in pulmonary arteries at lower radiation doses with improved lung image quality and fewer motion artifacts compared to high-pitch conventional CT and routine-pitch conventional dual-energy CT.

5.
Med J Malaysia ; 79(4): 494-497, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39086351

RESUMEN

The Academy of Medicine of Malaysia College of Paediatrics acknowledges the role of children in research and this position statement explores the ethical considerations in obtaining assent from minors in the Malaysian context. It highlights the importance in respecting children's agency and navigating cultural complexities. The College proposes flexibility in the minimum age for assent of at least nine years old, while emphasising the need for a tailored assent procedure. Addressing language and cultural diversities and expanding local empirical research on a formal assent process are some building blocks in developing a standardised nationwide process in obtaining assent from children.


Asunto(s)
Pediatría , Humanos , Malasia , Niño , Pediatría/ética , Pediatría/normas , Investigación Biomédica/ética , Investigación Biomédica/normas
6.
Dement Neurocogn Disord ; 23(3): 127-135, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39113754

RESUMEN

Background and Purpose: To ensure data privacy, the development of defacing processes, which anonymize brain images by obscuring facial features, is crucial. However, the impact of these defacing methods on brain imaging analysis poses significant concern. This study aimed to evaluate the reliability of three different defacing methods in automated brain volumetry. Methods: Magnetic resonance imaging with three-dimensional T1 sequences was performed on ten patients diagnosed with subjective cognitive decline. Defacing was executed using mri_deface, BioImage Suite Web-based defacing, and Defacer. Brain volumes were measured employing the QBraVo program and FreeSurfer, assessing intraclass correlation coefficient (ICC) and the mean differences in brain volume measurements between the original and defaced images. Results: The mean age of the patients was 71.10±6.17 years, with 4 (40.0%) being male. The total intracranial volume, total brain volume, and ventricle volume exhibited high ICCs across the three defacing methods and 2 volumetry analyses. All regional brain volumes showed high ICCs with all three defacing methods. Despite variations among some brain regions, no significant mean differences in regional brain volume were observed between the original and defaced images across all regions. Conclusions: The three defacing algorithms evaluated did not significantly affect the results of image analysis for the entire brain or specific cerebral regions. These findings suggest that these algorithms can serve as robust methods for defacing in neuroimaging analysis, thereby supporting data anonymization without compromising the integrity of brain volume measurements.

7.
Radiology ; 312(2): e233039, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-39105637

RESUMEN

Background Clinical decision making and drug development for fibrostenosing Crohn disease is constrained by a lack of imaging definitions, scoring conventions, and validated end points. Purpose To assess the reliability of MR enterography features to describe Crohn disease strictures and determine correlation with stricture severity. Materials and Methods A retrospective study of patients with symptomatic terminal ileal Crohn disease strictures who underwent MR enterography at tertiary care centers (Cleveland Clinic: September 2013 to November 2020; Mayo Clinic: February 2008 to March 2019) was conducted by using convenience sampling. In the development phase, blinded and trained radiologists independently evaluated 26 MR enterography features from baseline and follow-up examinations performed more than 6 months apart, with no bowel resection performed between examinations. Follow-up examinations closest to 12 months after baseline were selected. Reliability was assessed using the intraclass correlation coefficient (ICC). In the validation phase, after five features were redefined, reliability was re-estimated in an independent convenience sample using baseline examinations. Multivariable linear regression analysis identified features with at least moderate interrater reliability (ICC ≥0.41) that were independently associated with stricture severity. Results Ninety-nine (mean age, 40 years ± 14 [SD]; 50 male) patients were included in the development group and 51 (mean age, 45 years ± 16 [SD]; 35 female) patients were included in the validation group. In the development group, nine features had at least moderate interrater reliability. One additional feature demonstrated moderate reliability in the validation group. Stricture length (ICC = 0.85 [95% CI: 0.75, 0.91] and 0.91 [95% CI: 0.75, 0.96] in development and validation phase, respectively) and maximal associated small bowel dilation (ICC = 0.74 [95% CI: 0.63, 0.80] and 0.73 [95% CI: 0.58, 0.87] in development and validation group, respectively) had the highest interrater reliability. Stricture length, maximal stricture wall thickness, and maximal associated small bowel dilation were independently (regression coefficients, 0.09-3.97; P < .001) associated with stricture severity. Conclusion MR enterography definitions and scoring conventions for reliably assessing features of Crohn disease strictures were developed and validated, and feature correlation with stricture severity was determined. © RSNA, 2024 Supplemental material is available for this article. See also the article by Rieder and Ma et al in this issue. See also the editorial by Galgano and Summerlin in this issue.


Asunto(s)
Enfermedad de Crohn , Imagen por Resonancia Magnética , Humanos , Enfermedad de Crohn/diagnóstico por imagen , Femenino , Masculino , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Adulto , Reproducibilidad de los Resultados , Constricción Patológica/diagnóstico por imagen , Persona de Mediana Edad
10.
Small Methods ; : e2301610, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38693080

RESUMEN

Single impurities in insulators are now often used for quantum sensors and single photon sources, while nanoscale semiconductor doping features are being constructed for electrical contacts in quantum technology devices, implying that new methods for sensitive, non-destructive imaging of single- or few-atom structures are needed. X-ray fluorescence (XRF) can provide nanoscale imaging with chemical specificity, and features comprising as few as 100 000 atoms have been detected without any need for specialized or destructive sample preparation. Presently, the ultimate limits of sensitivity of XRF are unknown - here, gallium dopants in silicon are investigated using a high brilliance, synchrotron source collimated to a small spot. It is demonstrated that with a single-pixel integration time of 1 s, the sensitivity is sufficient to identify a single isolated feature of only 3000 Ga impurities (a mass of just 350 zg). With increased integration (25 s), 650 impurities can be detected. The results are quantified using a calibration sample consisting of precisely controlled numbers of implanted atoms in nanometer-sized structures. The results show that such features can now be mapped quantitatively when calibration samples are used, and suggest that, in the near future, planned upgrades to XRF facilities might achieve single-atom sensitivity.

11.
Funct Plant Biol ; 512024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38683936

RESUMEN

Effective identification and usage of genetic variation are prerequisites for developing nutrient-efficient cultivars. A collection of 94 safflower (Carthamus tinctorius ) genotypes (G) was investigated for important morphological and photosynthetic traits at four nitrogen (N) treatments. We found significant variation for all the studied traits except chlorophyll b (chl b ) among safflower genotypes, nitrogen treatments and G×N interaction. The examined traits showed a 2.82-50.00% increase in response to N application. Biological yield (BY) reflected a significantly positive correlation with fresh shoot weight (FSW), root length (RL), fresh root weight (FRW) and number of leaves (NOL), while a significantly positive correlation was also observed among carotenoids (C), chlorophyll a (chl a ), chl b and total chlorophyll content (CT) under all treatments. Superior genotypes with respect to plant height (PH), FSW, NOL, RL, FRW and BY were clustered into Group 3, while genotypes with better mean performance regarding chl a , chl b C and CT were clustered into Group 2 as observed in principal component analysis. The identified eight best-performing genotypes could be useful to develop improved nitrogen efficient cultivars. Genome-wide association analysis resulted in 32 marker-trait associations (MTAs) under four treatments. Markers namely DArT-45481731 , DArT-17812864 , DArT-15670279 and DArT-45482737 were found consistent. Protein-protein interaction networks of loci associated with MTAs were related to fatty acid and branched-chain amino acid metabolism and histone modifications.


Asunto(s)
Aminoácidos de Cadena Ramificada , Carthamus tinctorius , Ácidos Grasos , Estudio de Asociación del Genoma Completo , Nitrógeno , Carthamus tinctorius/genética , Carthamus tinctorius/metabolismo , Carthamus tinctorius/efectos de los fármacos , Nitrógeno/metabolismo , Ácidos Grasos/metabolismo , Aminoácidos de Cadena Ramificada/metabolismo , Genotipo , Código de Histonas/efectos de los fármacos , Clorofila/metabolismo , Sitios Genéticos
13.
Minerva Anestesiol ; 90(4): 321-329, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38498317

RESUMEN

INTRODUCTION: The aim of this systemic review and meta-analysis was to assess the impact of prophylactic use of esketamine on postoperative depression and quality of life in patients. EVIDENCE ACQUISITION: We searched for all articles on esketamine in patients after surgury in electronic data bases, including PubMed, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science, up to the June 2023.The included studies compared the impact of using esketamine and placebo on postoperative depression and quality of life in patients through randomized controlled trials. The outcome measurements consist of postoperative depression and indicators that can reflect the impact on patients' post Cochrane Risk of Bias tool in Review Manager 5.4 tool was adopted to assess the risk of bias. EVIDENCE SYNTHESIS: The study included a total of 11 randomized controlled trials with 1447 participants. This meta-analysis demonstrated that the prophylactic use of esketamine alleviated postoperative depressive symptoms (standardized mean difference [SMD]: -0.61; 95% confidence interval [CI]: -0.96 to -0.25; P=0.0008) and incidence (relative risk [RR]:0.37;95% [CI]: 0.22 to 0.62; P=0.0001), reducing the occurrence of postoperative depression, anxiety, and chronic pain. Additionally, it improved postoperative sleep quality and enhanced the postoperative quality of life for patients. CONCLUSIONS: Prophylactic use of esketamine during the preoperative and anesthesia period has shown significant benefits in improving postoperative quality of life. It can effectively alleviate postoperative depression, anxiety, and chronic pain, as well as enhance sleep quality.


Asunto(s)
Depresión , Ketamina , Complicaciones Posoperatorias , Calidad de Vida , Ketamina/uso terapéutico , Humanos , Depresión/prevención & control , Complicaciones Posoperatorias/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto
14.
Commun Biol ; 7(1): 280, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38448784

RESUMEN

X-ray computed tomography (XCT) and X-ray fluorescence (XRF) imaging are two non-invasive imaging techniques to study cellular structures and chemical element distributions, respectively. However, correlative X-ray computed tomography and fluorescence imaging for the same cell have yet to be routinely realized due to challenges in sample preparation and X-ray radiation damage. Here we report an integrated experimental and computational workflow for achieving correlative multi-modality X-ray imaging of a single cell. The method consists of the preparation of radiation-resistant single-cell samples using live-cell imaging-assisted chemical fixation and freeze-drying procedures, targeting and labeling cells for correlative XCT and XRF measurement, and computational reconstruction of the correlative and multi-modality images. With XCT, cellular structures including the overall structure and intracellular organelles are visualized, while XRF imaging reveals the distribution of multiple chemical elements within the same cell. Our correlative method demonstrates the feasibility and broad applicability of using X-rays to understand cellular structures and the roles of chemical elements and related proteins in signaling and other biological processes.


Asunto(s)
Investigación , Tomografía Computarizada por Rayos X , Rayos X , Radiografía , Imagen Óptica
15.
Nanoscale ; 16(11): 5760-5767, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38412012

RESUMEN

Magnetic nanomaterials are sought to provide new functionalities for applications ranging from information processing and storage to energy generation and biomedical imaging. MXenes are a rapidly growing family of two-dimensional transition metal carbides and nitrides with versatile chemical and structural diversity, resulting in a variety of interesting electronic and optical properties. However, strategies for producing MXenes with tailored magnetic responses remain underdeveloped and challenging. Herein, we incorporate elemental Ni and Co into Ti3C2Tx MXene by mixing with dilute metal chloride solutions. We achieve a uniform distribution of Ni and Co, confirmed by X-ray fluorescence (XRF) mapping with nanometer resolution, with Ni and Co concentrations of approximately 2 and 7 at% relative to the Ti concentration. The magnetic susceptibility of these Ni- and Co-incorporated Ti3C2Tx MXenes is one to two orders of magnitude larger than pristine Ti3C2Tx, illustrating the potential for dilute metal incorporation to enhance linear magnetic responses at room temperature.

17.
AJR Am J Roentgenol ; 222(3): e2329778, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37991334

RESUMEN

BACKGROUND. The higher spatial resolution and image contrast for iodine-containing tissues of photon-counting detector (PCD) CT may address challenges in evaluating small calcified vessels when performing lower extremity CTA by energy-integrating detector (EID) CTA. OBJECTIVE. The purpose of the study was to compare the evaluation of infrapopliteal vasculature between lower extremity CTA performed using EID CT and PCD CT. METHODS. This prospective study included 32 patients (mean age, 69.7 ± 11.3 [SD] years; 27 men, five women) who underwent clinically indicated lower extremity EID CTA between April 2021 and March 2022; participants underwent investigational lower extremity PCD CTA later the same day as EID CTA using a reduced IV contrast media dose. Two radiologists independently reviewed examinations in two sessions, each containing a random combination of EID CTA and PCD CTA examinations; the readers assessed the number of visualized fibular perforators, characteristics of stenoses at 11 infrapopliteal segmental levels, and subjective arterial sharpness. RESULTS. Mean IV contrast media dose was 60.0 ± 11.0 (SD) mL for PCD CTA versus 139.6 ± 11.8 mL for EID CTA (p < .001). The number of identified fibular perforators per lower extremity was significantly higher for PCD CTA than for EID CTA for reader 1 (R1) (mean ± SD, 6.4 ± 3.2 vs 4.2 ± 2.4; p < .001) and reader 2 (R2) (8.8 ± 3.4 vs 7.6 ± 3.3; p = .04). Reader confidence for assessing stenosis was significantly higher for PCD CTA than for EID CTA for R1 (mean ± SD, 82.3 ± 20.3 vs 78.0 ± 20.2; p < .001) but not R2 (89.8 ± 16.7 vs 90.6 ± 7.1; p = .24). The number of segments per lower extremity with total occlusion was significantly lower for PCD CTA than for EID CTA for R2 (mean ± SD, 0.5 ± 1.3 vs 0.9 ± 1.7; p = .04) but not R1 (0.6 ± 1.3 vs 1.0 ± 1.5; p = .07). The number of segments per lower extremity with clinically significant nonocclusive stenosis was significantly higher for PCD CTA than for EID CTA for R1 (mean ± SD, 2.2 ± 2.2 vs 1.6 ± 1.7; p = .01) but not R2 (1.1 ± 2.0 vs 1.1 ± 1.4; p = .89). Arterial sharpness was significantly greater for PCD CTA than for EID CTA for R1 (mean ± SD, 3.2 ± 0.5 vs 1.8 ± 0.5; p < .001) and R2 (3.2 ± 0.4 vs 1.7 ± 0.8; p < .001). CONCLUSION. PCD CTA yielded multiple advantages relative to EID CTA for visualizing small infrapopliteal vessels and characterizing associated plaque. CLINICAL IMPACT. The use of PCD CTA may improve vascular evaluation in patients with peripheral arterial disease.


Asunto(s)
Medios de Contraste , Fotones , Masculino , Humanos , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Estudios Prospectivos , Constricción Patológica , Fantasmas de Imagen , Tomografía Computarizada por Rayos X/métodos , Extremidad Inferior/diagnóstico por imagen
18.
Trop Biomed ; 40(3): 370-374, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37897172

RESUMEN

Beetles (Coleoptera) are known to constitute forensic evidence in medico-legal investigations as their presence can be used to date human remains in almost all decomposition stages. Many forensic studies focus on the successional colonization pattern of flies (Diptera); however, beetles have not so far been studied extensively for this aspect. A beetle of the genus Afromorgus Scholtz, 1986, A. chinensis (Boheman, 1858) (Scarabaeoidea: Trogidae), was found beneath a late decaying rabbit carcass at Paya Indah Wetland, Dengkil, Malaysia, for the first time. Both genus and species are already known to occur in Malaysia from literature.


Asunto(s)
Escarabajos , Dípteros , Entomología Forense , Animales , Conejos , Humanos , Cambios Post Mortem , Ciencias Forenses , Entomología , Cadáver , Conducta Alimentaria
19.
J Oral Sci ; 65(4): 237-242, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37612067

RESUMEN

PURPOSE: This study was conducted to investigate the dental and palatal arch dimensions of male and female siblings in relation to gender and age, using three-dimensional (3D) digital casts. METHODS: This study involved 54 subjects (27 pairs) of male-female siblings aged 15 to 45 years. Dental casts were digitized and analyzed for tooth size (TS), arch width (AW), arch length (AL), arch length discrepancy (ALD), and palatal arch dimensions (PAD). The data obtained were subjected to t-tests, and the palatal curvature (PC) was modeled using a fourth-order polynomial. RESULTS: Significant differences (P < 0.05) between the sexes were found in the mesiodistal TS, particularly in all canines, as well as 16, 36, 46, and 41. Maxillary AW and AL were also significantly (P < 0.05) influenced by sexes. Most arch parameters were more prominent in male siblings, and the effect of age on PC differed between the sexes. In addition, the PC of adolescent females was mostly superimposed on adult females relative to males. CONCLUSION: Among siblings, males were found to have significantly larger dental arch dimensions than females. Furthermore, PC showed some differences between the sexes in both the frontal and sagittal planes.

20.
Sci Adv ; 9(32): eadg8869, 2023 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-37566654

RESUMEN

Dopamine is broadly implicated in reinforcement learning, but how patterns of dopamine activity are generated is poorly resolved. Here, we demonstrate that two ion channels, Kv4.3 and BKCa1.1, regulate the pattern of dopamine neuron firing and dopamine release on different time scales to influence separate phases of reinforced behavior in mice. Inactivation of Kv4.3 in VTA dopamine neurons increases ex vivo pacemaker activity and excitability that is associated with increased in vivo firing rate and ramping dynamics before lever press in a learned instrumental paradigm. Loss of Kv4.3 enhances performance of the learned response and facilitates extinction. In contrast, loss of BKCa1.1 increases burst firing and phasic dopamine release that enhances learning of an instrumental response and enhances extinction burst lever pressing in early extinction that is associated with a greater change in activity between reinforced and unreinforced actions. These data demonstrate that disruption of intrinsic regulators of neuronal activity differentially affects dopamine dynamics during reinforcement and extinction learning.


Asunto(s)
Dopamina , Neuronas Dopaminérgicas , Ratones , Animales , Refuerzo en Psicología , Aprendizaje , Canales Iónicos
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