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1.
BMC Health Serv Res ; 24(1): 1120, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39334259

RESUMO

BACKGROUND: Valid and reliable measures for assessing health activation in school-aged children are currently lacking. This study aimed to develop a scale to measure health activation and evaluate its psychometric properties among English-speaking primary school children in Singapore. METHODS: The development of the Health Activation Scale for Children (HAS-C) involved an extensive literature review, expert consultations, cognitive interviews with primary school children, and thorough discussions for dimension and item refinement. A cross-sectional study was conducted with 597 children aged 8 to 12 years, recruited from four mainstream primary schools, comprising 50.1% boys and 64.8% Chinese students. The potential scale, along with other measures, was independently completed by the children. Descriptive statistics were provided for individual scale items. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were performed to assess factorial validity. Convergent validity was examined by correlating the scale scores with scores of health confidence and self-efficacy measures. Hypothesis-testing validity was evaluated by assessing the scale's correlation with self-reported health behaviours, including daily consumption of vegetables and fruits, time spent on sedentary activities and physical activities. Internal consistency reliability was measured using Cronbach's alpha. RESULTS: EFA suggested a three-factor structure for the 12-item HAS-C, which was subsequently confirmed by CFA with a good model fit. All three HAS-C dimension scores demonstrated moderate correlations (rho = 0.34-0.52) with health confidence and self-efficacy measures, indicating good convergent validity. They were positively correlated with more vegetable and fruit intakes, more time spent on exercises, and negatively correlated with time spent on sedentary activities, supporting hypothesis-testing validity. Internal consistency reliability for individual HAS-C dimensions was generally acceptable, with Cronbach's alpha values of 0.70 or above. CONCLUSION: The 12-item multi-dimensional HAS-C exhibited good validity and reliability, making it a valuable tool for assessing health activation in primary school-aged children.


Assuntos
Promoção da Saúde , Psicometria , Humanos , Criança , Masculino , Feminino , Promoção da Saúde/métodos , Estudos Transversais , Singapura , Reprodutibilidade dos Testes , Inquéritos e Questionários/normas , Comportamentos Relacionados com a Saúde , Análise Fatorial , Avaliação de Resultados em Cuidados de Saúde
2.
Gastroenterology ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39147169

RESUMO

BACKGROUND AND AIMS: Peritoneal metastasis (PM) in gastric cancer (GC) is associated with poor prognosis and significant morbidity. We sought to understand the genomic, transcriptomic, and tumor microenvironment (TME) features that contribute to peritoneal organotropism in GC. METHODS: We conducted a comprehensive multi-omic analysis of 548 samples from 326 patients, including primary tumors, matched normal tissues; peritoneal metastases, and adjacent-normal peritoneal tissues. We used whole exome sequencing, whole transcriptome sequencing, and digital spatial profiling to investigate molecular alterations, gene expression patterns, and TME characteristics associated with PM. RESULTS: Our analysis identified specific genomic alterations in primary tumors, including mutations in ELF3, CDH1, and PIGR, and TME signatures, such as stromal infiltration and M2 macrophage enrichment, associated with increased risk of PM. We observed distinct transcriptional programs and immune compositions in GCPM compared with liver metastases, highlighting the importance of the TME in transcoelomic metastasis. We found differential expression of therapeutic targets between primary tumors and PM, with lower CLDN18.2 and FGFR2b expression in PM. We unravel the roles of the TME in niche reprogramming within the peritoneum, and provide evidence of pre-metastatic niche conditioning even in early GC without clinical PM. These findings were further validated using a humanized mouse model, which demonstrated niche remodeling in the peritoneum during transcoelomic metastasis. CONCLUSION: Our study provides a comprehensive molecular characterization of GCPM and unveils key biological principles underlying transcoelomic metastasis. The identified predictive markers, therapeutic targets, and TME alterations offer potential avenues for targeted interventions and improved patient outcomes.

3.
Xenobiotica ; : 1-24, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39175333

RESUMO

Cytochrome P40 (CYP) enzymes dominate the metabolism of numerous endogenous and xenobiotic substances. While it is commonly believed that CYP-catalysed reactions result in the detoxication of foreign substances, these reactions can also yield reactive intermediates that can bind to cellular macromolecules to cause cytotoxicity or irreversibly inactivate CYPs that create them.Mechanism-based inactivation (MBI) produces either irreversible or quasi-irreversible inactivation and is commonly caused by CYP metabolic bioactivation to an electrophilic reactive intermediate. Many drugs that have been known to cause MBI in CYPs have been discovered as perpetrators in drug-drug interactions throughout the last 20-30 years.This review will highlight the key findings from the recent literature about the mechanisms of CYP enzyme inhibition, with a focus on the broad mechanistic elements of MBI for widely used drugs linked to the phenomenon. There will also be a brief discussion of the clinical or pharmacokinetic consequences of CYP inactivation with regard to drug interaction and toxicity risk.Gaining knowledge about the selective inactivation of CYPs by common therapeutic drugs helps with the assessment of factors that affect the systemic clearance of co-administered drugs and improves comprehension of anticipated interactions with other drugs or xenobiotics.

4.
Sci Rep ; 14(1): 17522, 2024 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080370

RESUMO

Peritoneal metastasis (PM), the regional progression of intra-abdominal malignancies, is a common sequelae of colorectal cancer (CRC). Immunotherapy is slated to be effective in generating long-lasting anti-tumour response as it utilizes the specificity and memory of the immune system. In the tumour microenvironment, tumour associated macrophages (TAMs) are posited to create an anti-inflammatory pro-tumorigenic environment. In this paper, we aimed to identify immunomodulatory factors associated with colorectal PM (CPM). A publicly available colorectal single cell database (GSE183916) was analysed to identify possible immunological markers that are associated with the activation of macrophages in cancers. Immunohistochemical analysis for V-set and immunoglobin containing domain 4 (VSIG4) expression was performed on tumour microarrays (TMAs) of tumours of colorectal origin (n = 211). Expression of VSIG4 in cell-free ascites obtained from CPM patients (n = 39) was determined using enzyme-linked immunosorbent assay (ELISA). CD163-positive TAMs cluster expression was extracted from a publicly available single cell database and evaluated for the top 100 genes. From these macrophage-expressed genes, VSIG4, a membrane protein produced by the M2 macrophages, mediates the up-regulation of anti-inflammatory and down-regulation of pro-inflammatory macrophages, contributing to an overall anti-inflammatory state. CRC TMA IHC staining showed that low expression of VSIG4 in stromal tissues of primary CRC are associated with poor prognosis (p = 0.0226). CPM ascites also contained varying concentrations of VSIG4, which points to a possible role of VSIG4 in the ascites. The contribution of VSIG4 to CPM development can be further evaluated for its potential as an immunotherapeutic agent.


Assuntos
Neoplasias Colorretais , Neoplasias Peritoneais , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/imunologia , Regulação Neoplásica da Expressão Gênica , Imunomodulação , Comunicação Parácrina , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/metabolismo , Microambiente Tumoral/imunologia , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/imunologia
5.
Front Oncol ; 14: 1272432, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38939336

RESUMO

Introduction: Field cancerization is suggested to arise from imbalanced differentiation in individual basal progenitor cells leading to clonal expansion of mutant cells that eventually replace the epithelium, although without evidence. Methods: We performed deep sequencing analyses to characterize the genomic and transcriptomic landscapes of field change in two patients with synchronous aerodigestive tract tumors. Results: Our data support the emergence of numerous genetic alterations in cancer-associated genes but refutes the hypothesis that founder mutation(s) underpin this phenomenon. Mutational signature analysis identified defective homologous recombination as a common underlying mutational process unique to synchronous tumors. Discussion: Our analyses suggest a common etiologic factor defined by mutational signatures and/or transcriptomic convergence, which could provide a therapeutic opportunity.

6.
Phys Rev E ; 109(5-1): 054124, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38907442

RESUMO

Glass formers are, in general, classified as strong or fragile depending on whether their relaxation rates follow Arrhenius or super-Arrhenius temperature dependence. There are, however, notable exceptions, such as water, which exhibit a fragile-to-strong (FTS) transition and behave as fragile and strong, respectively, at high and low temperatures. In this work, the FTS transition is studied using a distinguishable-particle lattice model previously demonstrated to be capable of simulating both strong and fragile glasses [C.-S. Lee, M. Lulli, L.-H. Zhang, H.-Y. Deng, and C.-H. Lam, Phys. Rev. Lett. 125, 265703 (2020)0031-900710.1103/PhysRevLett.125.265703]. Starting with a bimodal pair-interaction distribution appropriate for fragile glasses, we show that by narrowing down the energy dispersion in the low-energy component of the distribution, a FTS transition is observed. The transition occurs at a temperature at which the stretching exponent of the relaxation is minimized, in agreement with previous molecular dynamics simulations.

7.
Soft Matter ; 20(24): 4827, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38836328

RESUMO

Correction for 'Surface mobility gradient and emergent facilitation in glassy films' by Qiang Zhai et al., Soft Matter, 2024, https://doi.org/10.1039/D4SM00221K.

8.
Hum Vaccin Immunother ; 20(1): 2344983, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38767209

RESUMO

Herpes zoster (HZ) is a painful rash which typically affects older adults. This is of concern in Asia-Pacific given its aging population. As HZ epidemiology and burden are evolving, this systematic literature review aimed to update the current understanding of HZ burden and associated costs for selected Asia-Pacific locales. MEDLINE and Embase were searched for English articles of HZ studies conducted in Australia, China, Hong Kong, Japan, Korea, New Zealand, Singapore, and Taiwan. Eligible outcomes included HZ incidence and prevalence, occurrence of HZ-related complications, healthcare resource utilization, costs, and HZ-associated quality of life outcomes. This paper focused on HZ data in the general adult population (N = 90 articles). Substantial HZ-related disease and economic burden were observed in these locales, consistent with global trends. These findings reinforce the increasing burden of HZ and need for preventive strategies, which may include raising awareness and encouraging timely vaccination.


Herpes zoster, also known as shingles, is a painful rash that usually resolves after a few weeks, although some people experience serious or long-lasting complications. Shingles is common, affecting around one in every three individuals in their lifetime, and older persons are more likely to have shingles. Given the aging population in the Asia-Pacific region, shingles represents an increasingly important health issue as the proportion of older people increases. Vaccination can help prevent shingles and avoid its complications. New data on the trends and burden of shingles in this region are regularly generated. Therefore, in this study, we looked at studies from selected countries published over the past twenty years to summarize the latest available information on: how many people experience shingles in selected Asia-Pacific areas, how these individuals and societies are affected, and the related costs. Consistent with previous research, this study observed an increasing trend in the number of persons with shingles and costs of managing it, especially in older adults. In populations that are aging, there is a need for ways to reduce the risk of shingles and to lessen its burden on the healthcare system and society. Our findings can help to inform current development of strategies to reduce the risk of shingles, including education (on the burden and risk of shingles) and encouraging uptake of preventive measures.


Assuntos
Efeitos Psicossociais da Doença , Herpes Zoster , Humanos , Ásia/epidemiologia , Austrália/epidemiologia , Herpes Zoster/epidemiologia , Herpes Zoster/economia , Incidência , Nova Zelândia/epidemiologia , Prevalência , Qualidade de Vida , Adulto
9.
Soft Matter ; 20(22): 4389-4394, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38757511

RESUMO

Confining glassy polymers into films can substantially modify their local and film-averaged properties. We present a lattice model of film geometry with void-mediated facilitation behaviors but free from any elasticity effect. We analyze the spatially varying viscosity to delineate the transport properties of glassy films. The film mobility measurements reported by Yang et al., Science, 2010, 328, 1676 are successfully reproduced. The flow exhibits a crossover from a simple viscous flow to a surface-dominated regime as the temperature decreases. The propagation of a highly mobile front induced by the free surface is visualized in real space. Our approach provides a microscopic treatment of the observed glassy phenomena.

10.
Inorg Chem ; 63(23): 10490-10499, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38801717

RESUMO

Al4SiC4 is a ternary wide-band-gap semiconductor with a high strength-to-weight ratio and excellent oxidation resistance. It consists of slabs of Al4C3 separated by SiC layers with the space group of P63mc. The space group allows Si to occupy two different 2a Wykoff sites, with previous studies reporting that Si occupies only one of the two sites, giving it an ordered structure. Another hitherto unexplored possibility is that Si can be randomly distributed on both 2a sites. In this work, we revisit the published ordered crystal structure using experimental methods and density functional theory (DFT). Al4SiC4 was synthesized by high-temperature sintering at 1800 °C from a powder mixture of Al4C3 and SiC. Neutron diffraction confirmed that Al4SiC4 crystallized with the space group of P63mc, with diffraction patterns that could be fitted to both the ordered and the disordered structures. Scanning transmission electron microscopy, however, provided clear evidence supporting the latter, with DFT calculations further confirming that it is 0.16 eV lower in energy per Al4SiC4 formula unit than the former. TEM analysis revealed Al vacancies in some of the atomic layers that can introduce p-type doping and direct band gaps of 0.7 and 1.2 eV, agreeing with our optical measurements. Finally, we propose that although the calculated formation energy of the Al vacancies is high, the vacancies are stabilized by entropy effects at the high synthesis temperature. This indicates that the cooling procedure after high-temperature synthesis can be important in determining the vacancy content and the electronic properties of Al4SiC4.

12.
Nano Lett ; 24(18): 5562-5569, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38682815

RESUMO

Transition metal trichalcogenides (TMTCs) offer remarkable opportunities for tuning electronic states through modifications in chemical composition, temperature, and pressure. Despite considerable interest in TMTCs, there remain significant knowledge gaps concerning the evolution of their electronic properties under compression. In this study, we employ experimental and theoretical approaches to comprehensively explore the high-pressure behavior of the electronic properties of TiS3, a quasi-one-dimensional (Q1D) semiconductor, across various temperature ranges. Through high-pressure electrical resistance and magnetic measurements at elevated pressures, we uncover a distinctive sequence of phase transitions within TiS3, encompassing a transformation from an insulating state at ambient pressure to the emergence of an incipient superconducting state above 70 GPa. Our findings provide compelling evidence that superconductivity at low temperatures of ∼2.9 K is a fundamental characteristic of TiS3, shedding new light on the intriguing high-pressure electronic properties of TiS3 and underscoring the broader implications of our discoveries for TMTCs in general.

13.
PLoS One ; 19(4): e0300594, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38574044

RESUMO

BACKGROUND: Peritoneal sarcomatosis (PS) is a difficult entity to treat with limited options and guarded prognosis. We aimed to determine if the addition of hyperthermic intraperitoneal chemotherapy (HIPEC) could offer superior local recurrence-free survival in patients with retroperitoneal sarcoma at high risk of developing PS as opposed to extended resection alone. METHODS: This is a single arm, phase II intervention study where all patients with recurrent localized retroperitoneal sarcoma considered at high risk of developing PS were considered for enrolment (ClinicalTrials.gov identifier: NCT03792867). Upon enrolment, patients underwent vigorous preoperative testing to ensure fitness for the procedure. During surgery, patients underwent extended resection and HIPEC with doxorubicin. Patients were followed-up every 2 weeks (± 10 days) for the first month and subsequently every three months (± 1 month) up to a year post-surgery, and were assessed for potential chemotherapy toxicity and post-treatment complications. After a year from resection and HIPEC, patients were followed-up either during routine clinic review or contacted via telephone every year (± 1 month) for 3 years. RESULTS: Six patients were recruited but one patient dropped out due to adverse and unexpected intraoperative events. The remaining patients completed the procedure uneventfully. Post-HIPEC, all patients recurred with a disease-free interval ranging from six to 24 months. Three patients died due to complications from recurrent disease whereas the remaining three patients are alive as of their last visit. The overall survival at time at reporting ranged between 22 to 56 months. CONCLUSION: The procedure is feasible with no major morbidity to patients. However, we are unable to recommend for it to be implemented as a routine procedure at this current stage due to lack of improved survival outcomes. Further multi-institutional studies may be conducted to yield better results.


Assuntos
Hipertermia Induzida , Neoplasias Peritoneais , Neoplasias Retroperitoneais , Sarcoma , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Procedimentos Cirúrgicos de Citorredução , Hipertermia Induzida/métodos , Quimioterapia Intraperitoneal Hipertérmica , Neoplasias Peritoneais/cirurgia , Projetos Piloto , Neoplasias Retroperitoneais/cirurgia , Sarcoma/tratamento farmacológico , Sarcoma/cirurgia
14.
iScience ; 27(3): 109231, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439966

RESUMO

ApoE regulates neurogenesis, although how it influences genetic programs remains elusive. Cortical neurons induced from isogenic control and ApoE-/- human neural stem cells (NSCs) recapitulated key transcriptomic signatures of in vivo counterparts identified from single-cell human midbrain. Surprisingly, ApoE expression in NSC and neural progenitor cells (NPCs) is not required for differentiation. Instead, ApoE prevents the over-proliferation of non-neuronal cells during extended neuronal culture when it is not expressed. Elevated miR-199a-5p level in ApoE-/- cells lowers the EZH1 protein and the repressive H3K27me3 mark, a phenotype rescued by miR-199a-5p steric inhibitor. Reduced H3K27me3 at genes linked to extracellular matrix organization and angiogenesis in ApoE-/- NPC correlates with their aberrant expression and phenotypes in neurons. Interestingly, the ApoE coding sequence, which contains many predicted miR-199a-5p binding sites, can repress miR-199a-5p without translating into protein. This suggests that ApoE maintains neurons integrity through the target-directed miRNA degradation of miR-199a-5p, imparting the H3K27me3-mediated repression of non-neuronal genes during differentiation.

15.
Nature ; 625(7995): 483-488, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38233620

RESUMO

Heavy-fermion metals are prototype systems for observing emergent quantum phases driven by electronic interactions1-6. A long-standing aspiration is the dimensional reduction of these materials to exert control over their quantum phases7-11, which remains a significant challenge because traditional intermetallic heavy-fermion compounds have three-dimensional atomic and electronic structures. Here we report comprehensive thermodynamic and spectroscopic evidence of an antiferromagnetically ordered heavy-fermion ground state in CeSiI, an intermetallic comprising two-dimensional (2D) metallic sheets held together by weak interlayer van der Waals (vdW) interactions. Owing to its vdW nature, CeSiI has a quasi-2D electronic structure, and we can control its physical dimension through exfoliation. The emergence of coherent hybridization of f and conduction electrons at low temperature is supported by the temperature evolution of angle-resolved photoemission and scanning tunnelling spectra near the Fermi level and by heat capacity measurements. Electrical transport measurements on few-layer flakes reveal heavy-fermion behaviour and magnetic order down to the ultra-thin regime. Our work establishes CeSiI and related materials as a unique platform for studying dimensionally confined heavy fermions in bulk crystals and employing 2D device fabrication techniques and vdW heterostructures12 to manipulate the interplay between Kondo screening, magnetic order and proximity effects.

16.
Neural Regen Res ; 19(7): 1415-1416, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38051874
17.
Surg Infect (Larchmt) ; 25(1): 7-18, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38150507

RESUMO

Background: Appendicitis is an inflammatory condition that requires timely and effective intervention. Despite being one of the most common surgically treated diseases, the condition is difficult to diagnose because of atypical presentations. Ultrasound and computed tomography (CT) imaging improve the sensitivity and specificity of diagnoses, yet these tools bear the drawbacks of high operator dependency and radiation exposure, respectively. However, new artificial intelligence tools (such as machine learning) may be able to address these shortcomings. Methods: We conducted a state-of-the-art review to delineate the various use cases of emerging machine learning algorithms for diagnosing and managing appendicitis in recent literature. The query ("Appendectomy" OR "Appendicitis") AND ("Machine Learning" OR "Artificial Intelligence") was searched across three databases for publications ranging from 2012 to 2022. Upon filtering for duplicates and based on our predefined inclusion criteria, 39 relevant studies were identified. Results: The algorithms used in these studies performed with an average accuracy of 86% (18/39), a sensitivity of 81% (16/39), a specificity of 75% (16/39), and area under the receiver operating characteristic curves (AUROCs) of 0.82 (15/39) where reported. Based on accuracy alone, the optimal model was logistic regression in 18% of studies, an artificial neural network in 15%, a random forest in 13%, and a support vector machine in 10%. Conclusions: The identified studies suggest that machine learning may provide a novel solution for diagnosing appendicitis and preparing for patient-specific post-operative complications. However, further studies are warranted to assess the feasibility and advisability of implementing machine learning-based tools in clinical practice.


Assuntos
Apendicite , Humanos , Apendicite/diagnóstico por imagem , Apendicite/cirurgia , Inteligência Artificial , Aprendizado de Máquina , Apendicectomia , Algoritmos
18.
Ann Surg Open ; 4(4): e339, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38144489

RESUMO

Objective: To examine the association between the performance of mapping biopsies and surgical outcomes postexcision of extramammary Paget's disease (EMPD). Background: Primary EMPD is a rare entity associated with poorly defined surgical margins and difficult-to-access sites of lesions. Surgical resection with clear margins remains the preferred management method. The use of mapping biopsies might be beneficial, particularly in lowering disease recurrence. Methods: Available literature was reviewed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology before a fixed-effect meta-analysis was performed to identify the presence of a correlation between performing mapping biopsies and positive margins on permanent sections as well as disease-free survival. Additional study results not included in the quantitative assessment were qualitatively assessed and reported. Results: A total of 12 studies were shortlisted for final analysis. 294 patients who underwent mapping biopsies and 48 patients who did not undergo mapping biopsies were included in the assessment. Forest plot analysis revealed a pooled rate ratio of 0.50 (95% CI, 0.32-0.77) in the prevalence of positive margins in patients with mapping biopsies performed as compared to patients without. The pooled rate ratio of the prevalence of disease-free survival in patients with mapping biopsies performed as compared to patients without was 1.38 (95% CI, 1.03-1.84). Qualitative assessment of the remaining selected studies revealed equivocal results. Conclusions: Mapping biopsies are able to improve EMPD surgical excision outcomes but given the rarity of the disease and heterogeneity of mapping biopsy procedures, further confirmation with randomized controlled trials or a larger patient pool is necessary.

19.
Nano Lett ; 23(22): 10282-10289, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37906179

RESUMO

Quasiparticles consisting of correlated electron(s) and hole(s), such as excitons and trions, play important roles in the optical phenomena of van der Waals semiconductors and serve as unique platforms for studies of many-body physics. Herein, we report a gate-tunable exciton-to-trion transition in pressurized monolayer MoSe2, in which the electronic band structures are modulated continuously within a diamond anvil cell. The emission energies of both the exciton and trion undergo large blueshifts over 90 meV with increasing pressure. Surprisingly, the trion binding energy remains constant at 30 meV, regardless of the applied pressure. Combining ab initio density functional theory calculations and quantum Monte Carlo simulations, we find that the remarkable robustness of the trion binding energy originates from the spatially diffused nature of the trion wave function and the weak correlation between its constituent electron-hole pairs. Our findings shed light on the optical properties of correlated excitonic quasiparticles in low-dimensional materials.

20.
Artigo em Inglês | MEDLINE | ID: mdl-37839660

RESUMO

OBJECTIVE: Risk factors for severe postoperative bleeding after cardiac surgery remain multiple and incompletely elucidated. We evaluated the impact of intraoperative blood product transfusions, intravenous fluid administration, and persistently low core body temperature (CBT) at intensive care unit arrival on risk of perioperative bleeding leading to reexploration. METHODS: We retrospectively queried our tertiary care center's Society of Thoracic Surgeons Institutional Database for all index, on-pump, adult cardiac surgery patients between July 2016 and September 2022. Intraoperative fluid (crystalloid and colloid) and blood product administrations, as well as perioperative CBT data, were harvested from electronic medical records. Linear and nonlinear mixed models, treating surgeon as a random effect to account for inter-surgeon practice differences, were used to assess the association between above factors and reexploration for bleeding. RESULTS: Of 4037 patients, 151 (3.7%) underwent reexploration for bleeding. Reexplored patients experienced remarkably greater postoperative morbidity (23% vs 6%, P < .001) and 30-day mortality (14% vs 2%, P < .001). In linear models, progressively increasing IV crystalloid administration (adjusted odds ratio, 1.11, 95% confidence interval, 1.03-1.19) and decreasing CBT on intensive care unit arrival (adjusted odds ratio, 1.20; 95% confidence interval, 1.05-1.37) were associated with greater risk of bleeding leading to reexploration. Nonlinear analysis revealed increasing risk after ∼6 L of crystalloid administration and a U-shaped relationship between CBT and reexploration risk. Intraoperative blood product transfusion of any kind was not associated with reexploration. CONCLUSIONS: We found evidence of both dilution- and hypothermia-related effects associated with perioperative bleeding leading to reexploration in cardiac surgery. Interventions targeting modification of such risk factors may decrease the rate this complication.

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