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1.
Food Chem ; 462: 140920, 2025 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-39208732

RESUMEN

The use of direct injection ion mobility mass spectrometry (DI-IM-MS) to detect and identify betacyanin pigments in A. hortensis 'rubra' extracts was explored for the first time, with results compared to conventional LC-MS/MS analysis. The anti-inflammatory activities of leaf and seed extracts, alongside purified amaranthin and celosianin pigments, were investigated using a model of lipopolysaccharide (LPS)-activated murine macrophages. Extracts and purified pigments significantly inhibited the production of prostaglandin E2 and NO by up to 90% and 70%, respectively, and reduced the expression of Il6, Il1b, Nos2, and Cox2. Leaf and seed extracts also decreased secretion of Il6 and Il1b cytokines and reduced protein levels of Nos2 and Cox2. Furthermore, extracts and purified pigments demonstrated potent dose-dependent radical scavenging activity in a cellular antioxidant activity assay (CAA) without any cytotoxic effects. Our research highlights the promising biological potential of edible, climate-resilient A. hortensis 'rubra' as a valuable source of bioactive compounds.


Asunto(s)
Lipopolisacáridos , Macrófagos , Estrés Oxidativo , Extractos Vegetales , Ratones , Animales , Extractos Vegetales/farmacología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Células RAW 264.7 , Estrés Oxidativo/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Lipopolisacáridos/farmacología , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/inmunología , Ciclooxigenasa 2/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Espectrometría de Masas en Tándem
2.
J Zoo Wildl Med ; 55(3): 757-762, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39255219

RESUMEN

Administration of butorphanol, azaperone, and medetomidine (BAM) for immobilization of black howler monkeys (Alouatta pigra) has not been previously reported. In this observational study, 0.02 ml/kg of compounded BAM (butorphanol 27.3 mg/ml, azaperone 9.1 mg/ml, medetomidine 10.9 mg/ml) was administered IM in 10 captive black howler monkeys. Time to immobilization was recorded, an arterial blood gas performed, and at 5-min intervals, HR, RR, oscillometric arterial blood pressure, SPO2, and rectal temperature were measured. Naltrexone and atipamezole were administered IM at procedure completion and recovery times were recorded. If invasive procedures such as surgery were necessary and additional drugs needed, further data from that individual was removed from data analysis. Final BAM dosages were 0.55 ± 0.12 mg/kg butorphanol, 0.19 ± 0.04 mg/kg azaperone, and 0.22 ± 0.05 mg/kg medetomidine. Nine of 10 monkeys achieved sedation allowing for physical exam, venipuncture, and tuberculin skin testing within 4 ± 2 min. No monkeys reached a plane of immobilization allowing for intubation. Physiologic variables were acceptable for this species. Hypoxemia (SPO2 < 95%) was observed in three monkeys via pulse oximetry, and normoxemia was observed on arterial blood gas. Recovery was smooth and rapid. Therefore, BAM is a viable option for noninvasive procedures or as a premedication prior to induction of anesthesia in black howler monkeys.


Asunto(s)
Azaperona , Butorfanol , Hipnóticos y Sedantes , Inmovilización , Medetomidina , Animales , Medetomidina/administración & dosificación , Medetomidina/farmacología , Butorfanol/administración & dosificación , Butorfanol/farmacología , Azaperona/administración & dosificación , Azaperona/farmacología , Inmovilización/veterinaria , Inmovilización/métodos , Hipnóticos y Sedantes/administración & dosificación , Hipnóticos y Sedantes/farmacología , Femenino , Masculino , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/farmacología , Animales de Zoológico
3.
Glycobiology ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39255372

RESUMEN

Congenital disorders of glycosylation (CDG) are a group of rare monogenic human disorders caused by defects in the genes encoding the proteins that generate, attach, and modify glycans, thus disrupting cellular glycosylation machinery. Over 200 CDG caused by disruptions of 189 different genes are currently known. The multi-system disease manifestations of the CDG disorders highlight the importance of glycosylation across the organ systems. Clinical manifestations of CDG tend to group among genes contributing to the same glycosylation pathways, suggesting shared pathophysiology related to the glycosylation disruptions. However, the underlying glycosylation disruptions and pathophysiologic mechanisms responsible for specific CDG clinical manifestations have been determined for only a few hypoglycosylated proteins. The Frontiers in CDG Consortium (FCDGC) is an international network of clinical sites, laboratories, and patient advocacy groups established in 2019 to improve clinical symptoms, quality of life, and life expectancy for individuals with CDG. FCDGC seeks to answer decades of unresolved questions, address knowledge gaps, develop and validate new biochemical diagnostic techniques and therapeutic biomarkers, and explore novel therapeutic options for CDG. Over the past 5 years, FCDGC has launched a Natural History Study with over 300 CDG patients, discovered novel biomarkers suggesting new mechanisms of disease, and launched clinical trials aiming to restore appropriate glycosylation and targeting newly identified potential mechanisms of disease. Technical advances in glycobiology are making it increasingly possible to comprehensively catalog glycoproteomic data and to probe functional impact of altered glycosylation. My laboratory applies glycoproteomic technologies to samples from human subjects and genetic model systems to identify glycosylation abnormalities and unlock new insights from translational glycobiology. Current findings and accomplishments highlight the ongoing bottlenecks and knowledge gaps at intersections of glycobiology and clinical care requiring further investigation.

4.
iScience ; 27(9): 110668, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39246442

RESUMEN

Mapping the spatial interactions of cancer, immune, and stromal cell states presents novel opportunities for patient stratification and for advancing immunotherapy. While single-cell studies revealed significant molecular heterogeneity in prostate cancer cells, the impact of spatial stromal cell heterogeneity remains poorly understood. Here, we used cyclic immunofluorescent imaging on whole-tissue sections to uncover novel spatial associations between cancer and stromal cells in low- and high-grade prostate tumors and tumor-adjacent normal tissues. Our results provide a spatial map of single cells and recurrent cellular neighborhoods in the prostate tumor microenvironment of treatment-naive patients. We report unique populations of mast cells that show distinct spatial associations with M2 macrophages and regulatory T cells. Our results show disease-specific neighborhoods that are primarily driven by androgen receptor-positive (AR+) stromal cells and identify inflammatory gene networks active in AR+ prostate stroma.

6.
Front Immunol ; 15: 1412513, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39253084

RESUMEN

Expressed on the surface of CD8+ T cells, the CD8 co-receptor is a key component of the T cells that contributes to antigen recognition, immune cell maturation, and immune cell signaling. While CD8 is widely recognized as a co-stimulatory molecule for conventional CD8+ αß T cells, recent reports highlight its multifaceted role in both adaptive and innate immune responses. In this review, we discuss the utility of CD8 in relation to its immunomodulatory properties. We outline the unique structure and function of different CD8 domains (ectodomain, hinge, transmembrane, cytoplasmic tail) in the context of the distinct properties of CD8αα homodimers and CD8αß heterodimers. We discuss CD8 features commonly used to construct chimeric antigen receptors for immunotherapy. We describe the molecular interactions of CD8 with classical MHC-I, non-classical MHCs, and Lck partners involved in T cell signaling. Engineered and naturally occurring CD8 mutations that alter immune responses are discussed. The applications of anti-CD8 monoclonal antibodies (mABs) that target CD8 are summarized. Finally, we examine the unique structure and function of several CD8/mAB complexes. Collectively, these findings reveal the promising immunomodulatory properties of CD8 and CD8 binding partners, not only to uncover basic immune system function, but to advance efforts towards translational research for targeted immunotherapy.


Asunto(s)
Antígenos CD8 , Linfocitos T CD8-positivos , Inmunomodulación , Humanos , Antígenos CD8/metabolismo , Antígenos CD8/inmunología , Animales , Linfocitos T CD8-positivos/inmunología , Transducción de Señal/inmunología , Relación Estructura-Actividad , Inmunoterapia/métodos
7.
Curr Opin Infect Dis ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39259691

RESUMEN

PURPOSE OF REVIEW: We describe the epidemiology of the recent global surge in invasive group A streptococcal (GAS) disease and consider its proximate and distal causes. We highlight important knowledge gaps regarding clinical management and discuss potential strategies for prevention. RECENT FINDINGS: Rates of invasive GAS (iGAS) disease were increasing globally prior to the COVID-19 pandemic. Since mid-2022, following the worst years of the pandemic in 2020 and 2021, many countries with systems to monitor GAS syndromes have reported surges in cases of iGAS concurrent with increased scarlet fever, pharyngitis, and viral co-infections. The emergence of the hypervirulent M1UK strain as a cause of iGAS, particularly in high income countries, is concerning. New data are emerging on the transmission dynamics of GAS. GAS remains universally susceptible to penicillin but there are increasing reports of macrolide and lincosamide resistance, particularly in invasive isolates, with uncertain clinical consequences. Intravenous immunoglobulin is used widely for streptococcal toxic shock syndrome and necrotizing soft tissue infections, although there is limited clinical evidence, and none from a completed randomized controlled trial. Intensive and expensive efforts at population-level control of GAS infections and postinfectious autoimmune complications have been only partially successful. The great hope for control of GAS diseases remains vaccine development. However, all modern vaccine candidates remain in the early development stage. SUMMARY: In many countries, iGAS rates surged from mid-2022 in the aftermath of pandemic control measures and physical distancing. The emergence of a dominant hypervirulent strain is an important but incomplete explanation for this phenomenon. Clinical management of iGAS remains highly empirical and new data has not emerged. A vaccine remains the most likely means of achieving a sustainable reduction in the burden of iGAS.

8.
Schizophr Res ; 274: 57-65, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39260339

RESUMEN

BACKGROUND: Currently approved antipsychotics do not adequately treat negative symptoms (NS), which are a major determinant of functional disability in schizophrenia. KarXT, an M1 /M4 preferring muscarinic receptor agonist, has shown efficacy as a broad-spectrum monotherapy for the treatment of schizophrenia in participants with acute psychosis. Post hoc analyses evaluated the possibility that NS improve independently of positive symptoms with KarXT in a subgroup of participants with moderate-to-severe NS and no predominance of positive symptoms. METHODS: Data were pooled from the three pivotal trials of KarXT monotherapy in people with schizophrenia with an acute exacerbation of psychosis. All 3 studies used similar 5-week randomized, double-blind, placebo-controlled designs (modified intention-to-treat sample N = 640). PANSS criteria proposed in the literature identified a subset of study participants (n = 64) with prominent NS. RESULTS: KarXT was significantly better than placebo on PANSS Marder Negative Factor Scores in the full sample (p < .001; Cohen's d = 0.42) and more so in the prominent NS subgroup (p < .001; Cohen's d = 1.18). Further, the KarXT effect in the NS subgroup remained significant after accounting for changes in positive symptoms, depression/anxiety, disorganization, and hostility. CONCLUSIONS: Participants with prominent NS revealed greater improvement of NS following KarXT therapy than the full sample that persisted after accounting for positive and other symptoms. While these findings must be interpreted with caution, they are consistent with the possibility that NS improvements associated with KarXT are not secondary to improvements in other symptom domains and support further investigation in larger, stable outpatient studies.

9.
Clin Genitourin Cancer ; 22(6): 102208, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39265260

RESUMEN

BACKGROUND: Small cell bladder cancer (SCBC) is a rare histologic subtype with relative paucity of data regarding treatment response and outcomes. We reviewed 2 databases to compare outcomes in patients with localized SCBC treated with cystectomy versus concurrent chemoradiotherapy (CCRT). We hypothesized that survival would be similar with these therapy approaches. METHODS: We retrospectively reviewed our institutional and SEER-Medicare databases to identify patients with SCBC. Overall survival (OS) was determined from the date of diagnosis to last follow-up/death. For those with nonmetastatic disease, a multivariate Cox analysis was used to compare locoregional therapy with neoadjuvant chemotherapy (NAC) + cystectomy versus CCRT. RESULTS: We identified 53 patients in our institutional database and 1166 patients in SEER-Medicare with localized SCBC. Median OS (mOS) with NAC + cystectomy was 46 months (95% CI, 21-72) and 45 months (95% CI, 0-104) in the institutional and SEER-Medicare databases, respectively, whereas mOS with CCRT was 26 months (95% CI, 5-47) and 23 months (95% CI, 18-28) in the 2 series, respectively. In multivariate analysis, NAC followed by cystectomy was associated with an approximately 30% reduction in mortality compared to CCRT in both institutional and national databases but did not reach statistical significance (Institution HR 0.71, 95% CI, 0.22-2.4, P = .58; SEER HR 0.73, 95% CI, 0.49-1.08; P = .11). CONCLUSIONS: SCBC is very aggressive with limited survival observed in our institutional and SEER-Medicare datasets regardless of locoregional therapy used. There is an unmet need to define the optimal locoregional therapy for nonmetastatic stage and identify novel therapeutic targets.

10.
Ear Nose Throat J ; : 1455613241277696, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39264165
11.
mSystems ; : e0099224, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39264195

RESUMEN

Colibactin, a nonribosomal peptide/polyketide produced by pks+ Enterobacteriaceae, is a virulence factor and putative carcinogen that damages DNA by interstrand crosslinking (ICL). While the clb genes for colibactin biosynthesis have been identified, studies are needed to elucidate the mechanisms regulating colibactin production and activity. Here we perform untargeted metabolomics of pks+ Escherichia coli cultures to identify L-tryptophan as a candidate repressor of colibactin activity. When pks+ E. coli is grown in a minimal medium supplemented with L-tryptophan in vitro ICL of plasmid DNA is reduced by >80%. L-tryptophan does not affect the transcription of clb genes but protects from copper toxicity and triggers the expression of genes to export copper to the periplasm where copper can directly inhibit the ClbP peptidase domain. Thus, L-tryptophan and copper interact and repress colibactin activity, potentially reducing its carcinogenic effects in the intestine. IMPORTANCE: Colibactin is a small molecule produced by pks+ Enterobacteriaceae that damages DNA, leading to oncogenic mutations in human genomes. Colibactin-producing Escherichia coli (pks+) cells promote tumorigenesis in mouse models of colorectal cancer (CRC) and are elevated in abundance in CRC patient biopsies, making it important to identify the regulatory systems governing colibactin production. Here, we apply a systems biology approach to explore metabolite repression of colibactin production in pks+ E. coli. We identify L-tryptophan as a repressor of colibactin genotoxicity that stimulates the expression of genes to export copper to the periplasm where it can inhibit ClbP, the colibactin-activating peptidase. These results work toward an antibiotic-sparing, prophylactic strategy to inhibit colibactin genotoxicity and its tumorigenic effects in the intestine.

12.
PLoS One ; 19(9): e0308536, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39250471

RESUMEN

This study aimed to investigate the acute effects of lower limb wearable resistance on maximal horizontal deceleration biomechanics, across two different assessments. Twenty recreationally trained team sport athletes performed acceleration to deceleration assessments (ADA), and 5-0-5 change of direction (COD) tests across three load conditions (unloaded, 2% of BW, 4% of body weight (BW)), with load attached to the anterior and posterior thighs and shanks. Linear mixed effect models with participant ID as the random effect, and load condition as the fixed effect were used to study load-specific biomechanical differences in deceleration mechanics across both tests. Primary study findings indicate that for the ADA, in the 4% BW condition, participants exhibited significantly greater degrees of Avg Approach Momentum, as well as significant reductions in deceleration phase center of mass (COM) drop, and Avg Brake Step ground contact deceleration (GCD) in both the 2% BW, and 4% BW condition, compared to the unloaded condition. In the 5-0-5 tests, participants experienced significant reductions in Avg Approach Velocity, Avg deceleration (DEC), and Stopping Time in the 4% BW condition compared to the unloaded condition. Similar to the ADA test, participants also experienced significant reductions in Avg Brake Step GCD in both the 2% BW and 4% BW conditions, and significant increases in Avg Approach Momentum in the 4% BW condition, compared to the unloaded condition. Therefore, findings suggest that based on the test, and metric of interest, the addition of lower limb wearable resistance led to acute differences in maximal horizontal deceleration biomechanics. However, future investigations are warranted to further explore if the use of lower limb wearable resistance could present as an effective training tool in enhancing athlete's horizontal deceleration and change of direction performance.


Asunto(s)
Desaceleración , Extremidad Inferior , Dispositivos Electrónicos Vestibles , Humanos , Fenómenos Biomecánicos , Masculino , Extremidad Inferior/fisiología , Adulto Joven , Adulto , Femenino , Atletas , Entrenamiento de Fuerza/métodos , Entrenamiento de Fuerza/instrumentación , Aceleración
13.
JAMA Netw Open ; 7(9): e2434434, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39269702

RESUMEN

Importance: Synthetic nicotine is increasingly used in e-cigarette liquids along with flavors to appeal to youths. Regulatory loopholes have allowed tobacco manufacturers to use social media to target youths. Objective: To analyze the extent to which synthetic nicotine e-cigarette brands have implemented US Food and Drug Administration (FDA) health warning requirements and to evaluate the association between health warnings and user engagement on Instagram. Design, Setting, and Participants: In this cross-sectional study, posts from 25 brands were analyzed across a 14-month period (August 2021 to October 2022). A content analysis was paired with Warning Label Multi-Layer Image Identification, a computer vision algorithm designed to detect the presence of health warnings and whether the detected health warning complied with FDA guidelines by (1) appearing on the upper portion of the advertisement and (2) occupying at least 20% of the advertisement's area. Data analysis was performed from March to June 2024. Exposure: Synthetic nicotine e-cigarette advertisement on Instagram. Main Outcomes and Measures: The outcome variables were user engagement (number of likes and comments). Negative binomial regression analyses were used to evaluate the association between the presence and characteristics of health warnings and user engagement. Results: Of a total of 2071 posts, only 263 (13%) complied with both FDA health warning requirements. Among 924 posts with health warnings, 732 (79%) displayed warnings in the upper image portion, and 270 (29%) had a warning covering at least 20% of the pixel area. Posts with warnings received fewer comments than posts without warnings (mean [SD], 1.8 [2.5] vs 5.4 [11.7] comments; adjusted incident rate ratio [aIRR], 0.70; 95% CI, 0.57-0.86; P < .001). For posts containing warnings, a larger percentage of the warning label's pixel area was associated with fewer comments (aIRR, 0.96; 95% CI, 0.93-0.99; P = .003). Flavored posts with health warnings placed in the upper image portion received more likes than posts with warnings in the lower portion (mean [SD], 34.6 [35.2] vs 19.9 [19.2] likes; aIRR, 1.48; 95% CI, 1.07-2.06; P = .02). Conclusions and Relevance: In this cross-sectional study of synthetic nicotine brand Instagram accounts, 87% of sampled posts did not adhere to FDA health warning requirements in tobacco promotions. Enforcement of FDA compliant health warnings on social media may reduce youth engagement with tobacco marketing.


Asunto(s)
Publicidad , Sistemas Electrónicos de Liberación de Nicotina , Etiquetado de Productos , Medios de Comunicación Sociales , Humanos , Estudios Transversales , Estados Unidos , Publicidad/métodos , Etiquetado de Productos/métodos , Nicotina/efectos adversos , United States Food and Drug Administration
14.
J Biomech ; 175: 112298, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39217918

RESUMEN

The understanding of foot and ankle biomechanics is improving as new technology provides more detailed information about the motion of foot and ankle bones with biplane fluoroscopy, as well as the ability to analyze the hindfoot under weightbearing conditions with weightbearing computed tomography. Three-dimensional anatomical coordinate systems are necessary to describe the 3D alignment and kinematics of the foot and ankle. The lack of standard coordinate systems across research study sites can significantly alter experimental data analyses used for pre-surgical evaluation and post-operative outcome assessments. Clinical treatment paradigms are changing based on the expanding knowledge of complex pes planovalgus morphologies or progressive collapsing foot deformity, which is present in both neurologic and non-neurologic populations. Four patient cohorts were created from 10 flexible PCFD, 10 rigid PCFD, 10 adult cerebral palsy, and 10 asymptomatic control patients. Six coordinate systems were tested on both the talus and calcaneus for all groups. The aim of this study was to evaluate axes definitions for the subtalar joint across four different patient populations to determine the influence of morphology on the implementation of previously defined coordinate systems. Different morphologic presentations from various pathologies have a substantial impact on coordinate system definitions, given that numerous axes definitions are defined through geometric fits or manual landmark selection. Automated coordinate systems that align with clinically relevant anatomic planes are preferred. Principal component axes are automatic, but do not align with clinically relevant planes and should not be used for such analysis where anatomic planes are critical.


Asunto(s)
Calcáneo , Astrágalo , Humanos , Astrágalo/diagnóstico por imagen , Astrágalo/fisiopatología , Adulto , Calcáneo/diagnóstico por imagen , Masculino , Femenino , Persona de Mediana Edad , Fenómenos Biomecánicos , Parálisis Cerebral/fisiopatología , Parálisis Cerebral/diagnóstico por imagen , Parálisis Cerebral/patología
15.
mBio ; : e0215924, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39287439

RESUMEN

Lyme disease is the most common tick-borne disease in North America. A vaccine for use in humans is not available. Here, we detail the development of two chimeric vaccine antigens, BAF and Chv2M. BAF elicits Abs that target proteins and protein variants produced by Borreliella species in ticks (OspB and OspA) and mammals (FtlA/B). OspB serves as the backbone structure for the BAF chimeric. Two OspA221-240 epitope-containing domain (ECD) variants (#A1 and #A15) were inserted into a loop in OspB. The N-terminal region of the FtlA protein was joined to the C-terminus of the chimeric. The second chimeric, Chv2M, consists of L5 (loop 5) and H5 (helix 5) ECDs derived from diverse OspC proteins. Borreliella species produce OspC upon exposure to the bloodmeal and during early infection in mammals. Here, we demonstrate that BAF and Chv2M are potent immunogens that elicit Abs that bind to each component protein (FtlA, FtlB, OspB, and multiple OspA and OspC variants). Anti-BAF and anti-Chv2M Abs kill Borreliella burgdorferi strains through Ab-mediated complement-dependent and complement-independent mechanisms. Eighty percent (32/40) of mice that received a three-dose vaccine regimen were protected from infection with B. burgdorferi B31. Efficacy increased to 90% (18/20) when the amount of Chv2M was increased in the third vaccine dose. Readouts for infection were flaB PCR and seroconversion to VlsE. This study establishes proof of principle for a chimeric immunogen vaccine formulation that elicits Abs to multiple targets on the B. burgdorferi cell surface produced during tick and mammalian stages of the enzootic cycle.IMPORTANCELyme disease is a growing public health threat across parts of the Northern Hemisphere. Regions that can support sustained tick populations are expanding, and the incidence of tick-borne diseases is increasing. In light of the increasing risk of Lyme disease, effective preventive strategies are needed. Most vaccine development efforts have focused on outer surface protein A, a Borreliella burgdorferi protein produced only in ticks. Herein, we describe the development of a novel vaccine formulation consisting of two multivalent chimeric proteins that are immunogenic and elicit antibodies with bactericidal activity that target several cell surface proteins produced by the Lyme disease spirochetes in feeding ticks and mammals. In a broader sense, this study advances efforts to develop custom-designed vaccinogens comprised of epitope-containing domains from multiple proteins.

17.
Artículo en Inglés | MEDLINE | ID: mdl-39287622

RESUMEN

AlN is deposited on silicon carbide (SiC) for high-power electronics; in these devices, AlN acts as both a buffer layer for the growth of the active device and a thermal conductor. However, the mechanism of thermal transport through the AlN-SiC interfaces and through grain boundaries of AlN has not been clearly analyzed, even though AlN forms grain boundaries during the deposition process. The thermal properties of the AlN-SiC interface and the inversion domain boundaries (IDBs) of AlN were examined by a phonon transport model based on a nonequilibrium Green function formalism and first-principles calculations. The interface and grain boundary models were designed, and the thermal resistances (TRs) and origins of TR were examined. The TRs of the AlN-SiC interface and the IDB of AlN are much higher than the TRs of AlN and SiC of relevant thickness. Elemental intermixing and vacancy formation were modeled. The formation of charge-balanced defect of VAl + 3ON is thermodynamically favorable compared to other defects, indicating that ON induces formation of VAl. The charge-balanced defect combining VAl and ON increases the TRs of both AlN-SiC interfaces and AlN grain boundaries because vacancy defects induce larger changes in mass than all other defects, and TRs are proportional to changes in mass. In addition, VAl defects are increased by excess ON, resulting in a continuous increase in TR, and then, the calculated thermal boundary resistance (TBR) of the AlN-SiC interface with increased density of VAl by excess ON reaches the experimental TBR. Therefore, it is expected that the large increase in TR by the formation of VAl + ON would be suppressed by controlling the low O density during synthesis.

19.
Schizophr Bull Open ; 5(1): sgae021, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39296676

RESUMEN

Background and Hypothesis: Problematic gaming (PG) is an emerging mental health condition associated with significant adverse outcomes. Even though PG has been linked to other psychiatric disorders, its association with psychotic experiences (PEs) remains poorly explored to date. The aim of our study was to examine the association between both conditions in a large Brazilian community sample. We hypothesized that adolescents with PG were more likely to report PE compared with those without the disorder. Study Design: Our investigation was based on a cross-sectional subsample of a large Brazilian cohort (n = 1616; 13- to 21-year age range). Using the 7-item version of the Game Addiction Scale, participants were classified according to their gaming status: no PG, PG, or gaming addiction (GA). The association between PG, GA, and PE was assessed through linear regression analyses, which were adjusted for the presence of significant covariates, including other psychiatric conditions. Study Results: 9.5% (n = 154) presented PG and 2.7% (n = 43) had GA. 28.0% received any Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) diagnosis and the mean PE score was 9.39 (SD = 4.35). Participants presenting PG had greater levels of PE, compared with participants with no PG, even controlled by sociodemographic variables and the presence of any DSM-IV diagnosis (b = 0.96, 95% CI = 0.17-1.75, P = .017). Conclusions: According to our results, PG was significantly associated with PE, even in the presence of other covariates. Although preliminary, these results suggest that PG and PE may have shared neurobiological and/or behavioral pathways.

20.
J Vasc Access ; : 11297298241278394, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39297319

RESUMEN

BACKGROUND: Short peripheral catheter (SPC)-associated complications occur frequently in hospitalised neonates. Few studies have reported the use of SPC care bundles in resource-limited neonatal units. OBJECTIVE: To evaluate the impact of a SPC care bundle on SPC associated complications (infiltration, dislodgement, phlebitis) and catheter dwell time. METHODS: We conducted a quasi-experimental study comparing neonatal SPC complications during a 2-month baseline and a 2-month intervention period, where a SPC care bundle was introduced including hand hygiene, insertion site antisepsis, nurse assistance during cannulation, IV insertion carts and IV securement dressings. RESULTS: A total of 459 SPC days were observed in 223 neonates: 111 pre-intervention and 112 post-intervention (after SPC bundle implementation). Most neonates were preterm (208, 93.3%) with very or extremely low birth weight (133, 59.6%). SPC care bundle compliance was 43.8% for five bundle elements and 83.9% for four bundle elements. Most SPCs had unplanned removal within 48 h of insertion owing to infiltration or dislodgement (89/111 pre-intervention (80.2%) vs 90/112 post-intervention (80.4%); 0.974). No phlebitis was documented. The mean SPC dwell time was unchanged following bundle implementation (32.9 vs 34.2 h; p = 0.376). CONCLUSIONS: Infiltration and dislodgement occurred frequently necessitating replacement of four of every five SPCs. Despite moderate compliance with the SPC care bundle, the high rates of unplanned SPC removal and short duration of catheter dwell time were unchanged. CONTRIBUTION: The SPC care bundle did not improve catheter dwell time; further research is needed to identify strategies to reduce unplanned SPC removal and extend catheter dwell time in hospitalised neonates.

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