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1.
Nature ; 616(7955): 66-72, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36949195

RESUMO

Precise integration of two-dimensional (2D) semiconductors and high-dielectric-constant (k) gate oxides into three-dimensional (3D) vertical-architecture arrays holds promise for developing ultrascaled transistors1-5, but has proved challenging. Here we report the epitaxial synthesis of vertically aligned arrays of 2D fin-oxide heterostructures, a new class of 3D architecture in which high-mobility 2D semiconductor fin Bi2O2Se and single-crystal high-k gate oxide Bi2SeO5 are epitaxially integrated. These 2D fin-oxide epitaxial heterostructures have atomically flat interfaces and ultrathin fin thickness down to one unit cell (1.2 nm), achieving wafer-scale, site-specific and high-density growth of mono-oriented arrays. The as-fabricated 2D fin field-effect transistors (FinFETs) based on Bi2O2Se/Bi2SeO5 epitaxial heterostructures exhibit high electron mobility (µ) up to 270 cm2 V-1 s-1, ultralow off-state current (IOFF) down to about 1 pA µm-1, high on/off current ratios (ION/IOFF) up to 108 and high on-state current (ION) up to 830 µA µm-1 at 400-nm channel length, which meet the low-power specifications projected by the International Roadmap for Devices and Systems (IRDS)6. The 2D fin-oxide epitaxial heterostructures open up new avenues for the further extension of Moore's law.

2.
Genes Dev ; 33(11-12): 626-640, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30975722

RESUMO

Rhabdomyosarcoma (RMS) is an aggressive pediatric cancer composed of myoblast-like cells. Recently, we discovered a unique muscle progenitor marked by the expression of the Twist2 transcription factor. Genomic analyses of 258 RMS patient tumors uncovered prevalent copy number amplification events and increased expression of TWIST2 in fusion-negative RMS. Knockdown of TWIST2 in RMS cells results in up-regulation of MYOGENIN and a decrease in proliferation, implicating TWIST2 as an oncogene in RMS. Through an inducible Twist2 expression system, we identified Twist2 as a reversible inhibitor of myogenic differentiation with the remarkable ability to promote myotube dedifferentiation in vitro. Integrated analysis of genome-wide ChIP-seq and RNA-seq data revealed the first dynamic chromatin and transcriptional landscape of Twist2 binding during myogenic differentiation. During differentiation, Twist2 competes with MyoD at shared DNA motifs to direct global gene transcription and repression of the myogenic program. Additionally, Twist2 shapes the epigenetic landscape to drive chromatin opening at oncogenic loci and chromatin closing at myogenic loci. These epigenetic changes redirect MyoD binding from myogenic genes toward oncogenic, metabolic, and growth genes. Our study reveals the dynamic interplay between two opposing transcriptional regulators that control the fate of RMS and provides insight into the molecular etiology of this aggressive form of cancer.


Assuntos
Carcinogênese , Desenvolvimento Muscular , Proteína MyoD/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Rabdomiossarcoma/genética , Rabdomiossarcoma/metabolismo , Proteína 1 Relacionada a Twist/genética , Proteína 1 Relacionada a Twist/metabolismo , Células Cultivadas , Montagem e Desmontagem da Cromatina , DNA/metabolismo , Transição Epitelial-Mesenquimal , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Sequências Hélice-Alça-Hélice , Humanos , Proteína MyoD/química , Mioblastos/metabolismo , Proteínas Nucleares/genética , Proteínas Repressoras/química , Proteína 1 Relacionada a Twist/química
3.
PLoS Genet ; 19(6): e1010814, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37384781

RESUMO

Meta-diamides (e.g. broflanilide) and isoxazolines (e.g. fluralaner) are novel insecticides that target the resistant to dieldrin (RDL) subunit of insect γ-aminobutyric acid receptors (GABARs). In this study, we used in silico analysis to identify residues that are critical for the interaction between RDL and these insecticides. Substitution of glycine at the third position (G3') in the third transmembrane domain (TMD3) with methionine (G3'M TMD3), which is present in vertebrate GABARs, had the strongest effect on fluralaner binding. This was confirmed by expression of RDL from the rice stem borer, Chilo suppressalis (CsRDL) in oocytes of the African clawed frog, Xenopus laevis, where the G3'MTMD3 mutation almost abolished the antagonistic action of fluralaner. Subsequently, G3'MTMD3 was introduced into the Rdl gene of the fruit fly, Drosophila melanogaster, using the CRISPR/Cas9 system. Larvae of heterozygous lines bearing G3'MTMD3 did not show significant resistance to avermectin, fipronil, broflanilide, and fluralaner. However, larvae homozygous for G3'MTMD3 were highly resistant to broflanilide and fluralaner whilst still being sensitive to fipronil and avermectin. Also, homozygous lines showed severely impaired locomotivity and did not survive to the pupal stage, indicating a significant fitness cost associated with G3'MTMD3. Moreover, the M3'GTMD3 mutation in the mouse Mus musculus α1ß2 GABAR increased sensitivity to fluralaner. Taken together, these results provide convincing in vitro and in vivo evidence for both broflanilide and fluralaner acting on the same amino acid site, as well as insights into potential mechanisms leading to target-site resistance to these insecticides. In addition, our findings could guide further modification of isoxazolines to achieve higher selectivity for the control of insect pests with minimal effects on mammals.


Assuntos
Inseticidas , Receptores de GABA , Animais , Camundongos , Receptores de GABA/genética , Receptores de GABA/metabolismo , Dieldrin , Inseticidas/farmacologia , Inseticidas/química , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Larva/metabolismo , Mamíferos/metabolismo
4.
Bioinformatics ; 40(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960865

RESUMO

MOTIVATION: The data independent acquisition (DIA) mass spectrometry (MS) method is increasingly popular in the field of proteomics. But the loss of the correspondence between peptide ions and their spectra in DIA makes the identification challenging. One effective approach to reduce false positive identification is to calculate the deviation between the peptide's estimated retention time (RT) and measured RT. During this process, scaling the spectral library RT into the estimated RT, known as the RT calibration, is a prerequisite for calculating the deviation. Currently, within the DIA algorithm ecosystem, there is a lack of engine-independent and readily usable RT calibration toolkits. RESULTS: In this work, we introduce Calib-RT, a RT calibration method tailored to the characteristics of RT data. This method can achieve the nonlinear calibration across various data scales and tolerate a certain level of noise interference. Calib-RT is expected to enrich the open source DIA algorithm toolchain and assist in the development of DIA identification algorithms. AVAILABILITY AND IMPLEMENTATION: Calib-RT is released as an open source software under the MIT license and can be installed from PyPi as a python module. The source code is available on GitHub at https://github.com/chenghui03/Calib_RT.


Assuntos
Algoritmos , Espectrometria de Massas , Peptídeos , Proteômica , Software , Peptídeos/química , Peptídeos/análise , Espectrometria de Massas/métodos , Proteômica/métodos , Calibragem
5.
Ann Intern Med ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38976880

RESUMO

BACKGROUND: Apixaban, rivaroxaban, and warfarin have shown benefit for preventing major ischemic events, albeit with increased bleeding risk, among patients in the general population with atrial fibrillation (AF). However, data are scarce in patients with cirrhosis and AF. OBJECTIVE: To compare the effectiveness and safety of apixaban versus rivaroxaban and versus warfarin in patients with cirrhosis and AF. DESIGN: Population-based cohort study. SETTING: Two U.S. claims data sets (Medicare and Optum's de-identified Clinformatics Data Mart Database [2013 to 2022]). PARTICIPANTS: 1:1 propensity score (PS)-matched patients with cirrhosis and nonvalvular AF initiating use of apixaban, rivaroxaban, or warfarin. MEASUREMENTS: Primary outcomes included ischemic stroke or systemic embolism and major hemorrhage (intracranial hemorrhage or major gastrointestinal bleeding). Database-specific and pooled PS-matched rate differences (RDs) per 1000 person-years (PY) and Cox proportional hazard ratios (HRs) with 95% CIs were estimated, controlling for 104 preexposure covariates. RESULTS: Rivaroxaban initiators had significantly higher rates of major hemorrhagic events than apixaban initiators (RD, 33.1 per 1000 PY [95% CI, 12.9 to 53.2 per 1000 PY]; HR, 1.47 [CI, 1.11 to 1.94]) but no significant differences in rates of ischemic events or death. Consistently higher rates of major hemorrhage were found with rivaroxaban across subgroup and sensitivity analyses. Warfarin initiators also had significantly higher rates of major hemorrhage than apixaban initiators (RD, 26.1 per 1000 PY [CI, 6.8 to 45.3 per 1000 PY]; HR, 1.38 [CI, 1.03 to 1.84]), particularly hemorrhagic stroke (RD, 9.7 per 1000 PY [CI, 2.2 to 17.2 per 1000 PY]; HR, 2.85 [CI, 1.24 to 6.59]). LIMITATION: Nonrandomized treatment selection. CONCLUSION: Among patients with cirrhosis and nonvalvular AF, initiators of rivaroxaban versus apixaban had significantly higher rates of major hemorrhage and similar rates of ischemic events and death. Initiation of warfarin versus apixaban also contributed to significantly higher rates of major hemorrhagic events, including hemorrhagic stroke. PRIMARY FUNDING SOURCE: National Institutes of Health.

6.
Circulation ; 147(10): 782-794, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36762560

RESUMO

BACKGROUND: The benefit-risk profile of direct oral anticoagulants (DOACs) compared with warfarin, and between DOACs in patients with atrial fibrillation (AF) and chronic liver disease is unclear. METHODS: We conducted a new-user, retrospective cohort study of patients with AF and chronic liver disease who were enrolled in a large, US-based administrative database between January 1, 2011, and December 31, 2017. We assessed the effectiveness and safety of DOACs (as a class and individually) compared with warfarin, and between DOACs in patients with AF and chronic liver disease. The primary outcomes were hospitalization for ischemic stroke/systemic embolism and hospitalization for major bleeding. Inverse probability treatment weights were used to balance the treatment groups on measured confounders. RESULTS: Overall, 10 209 participants were included, with 4421 (43.2%) on warfarin, 2721 (26.7%) apixaban, 2211 (21.7%) rivaroxaban, and 851 (8.3%) dabigatran. The incidence rates per 100 person-years for ischemic stroke/systemic embolism were 2.2, 1.4, 2.6, and 4.4 for DOACs as a class, apixaban, rivaroxaban, and warfarin, respectively. The incidence rates per 100 person-years for major bleeding were 7.9, 6.5, 9.1, and 15.0 for DOACs as a class, apixaban, rivaroxaban, and warfarin, respectively. After inverse probability treatment weights, the risk of hospitalization for ischemic stroke/systemic embolism was significantly lower between DOACs as a class (hazard ratio [HR], 0.64 [95% CI, 0.46-0.90]) or apixaban (HR, 0.40 [95% CI, 0.19-0.82]) compared with warfarin, but not significantly different between rivaroxaban versus warfarin (HR, 0.76 [95% CI, 0.47-1.21]) or rivaroxaban versus apixaban (HR, 1.73 [95% CI, 0.91-3.29]). Compared with warfarin, the risk of hospitalization for major bleeding was lower with DOACs as a class (HR, 0.69 [95% CI, 0.58-0.82]), apixaban (HR, 0.60 [95% CI, 0.46-0.78]), and rivaroxaban (HR, 0.79 [95% CI, 0.62-1.0]). However, the risk of hospitalization for major bleeding was higher for rivaroxaban versus apixaban (HR, 1.59 [95% CI, 1.18-2.14]). CONCLUSIONS: Among patients with AF and chronic liver disease, DOACs as a class were associated with lower risks of hospitalization for ischemic stroke/systemic embolism and major bleeding versus warfarin. However, the incidence of clinical outcomes among patients with AF and chronic liver disease varied between individual DOACs and warfarin, and in head-to-head DOAC comparisons.


Assuntos
Fibrilação Atrial , Embolia , AVC Isquêmico , Hepatopatias , Acidente Vascular Cerebral , Humanos , Varfarina/efeitos adversos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/epidemiologia , Rivaroxabana/efeitos adversos , Anticoagulantes/efeitos adversos , Estudos de Coortes , Estudos Retrospectivos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/tratamento farmacológico , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Hemorragia/tratamento farmacológico , Dabigatrana/efeitos adversos , Hepatopatias/diagnóstico , Hepatopatias/epidemiologia , Embolia/epidemiologia , Embolia/prevenção & controle , Embolia/complicações , Administração Oral
7.
J Am Chem Soc ; 146(19): 12901-12906, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38701349

RESUMO

Cholesterol-rich membranes play a pivotal role in cancer initiation and progression, necessitating innovative approaches to target these membranes for cancer inhibition. Here we report the first case of unnatural peptide (1) assemblies capable of depleting cholesterol and inhibiting cancer cells. Peptide 1 self-assembles into micelles and is rapidly taken up by cancer cells, especially when combined with an acute cholesterol-depleting agent (MßCD). Click chemistry has confirmed that 1 depletes cell membrane cholesterol. It localizes in membrane-rich organelles, including the endoplasmic reticulum, Golgi apparatus, and lysosomes. Furthermore, 1 potently inhibits malignant cancer cells, working synergistically with cholesterol-lowering agents. Control experiments have confirmed that C-terminal capping and unnatural amino acid residues (i.e., BiP) are essential for both cholesterol depletion and potent cancer cell inhibition. This work highlights unnatural peptide assemblies as a promising platform for targeting the cell membrane in controlling cell fates.


Assuntos
Colesterol , Peptídeos , Humanos , Colesterol/química , Colesterol/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos
8.
J Am Chem Soc ; 146(4): 2624-2633, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38239111

RESUMO

Herein, we report a versatile reaction platform for tracelessly cleavable cysteine-selective peptide/protein modification. This platform offers highly tunable and predictable conjugation and cleavage by rationally estimating the electron effect on the nucleophilic halopyridiniums. Cleavable peptide stapling, antibody conjugation, enzyme masking/de-masking, and proteome labeling were achieved based on this facile pyridinium-thiol-exchange protocol.


Assuntos
Peptídeos , Proteoma , Cisteína/metabolismo
9.
Hum Brain Mapp ; 45(1): e26532, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38013633

RESUMO

Cortical gray to white matter signal intensity ratio (GWR) measured from T1-weighted magnetic resonance (MR) images was associated with neurodegeneration and dementia. We characterized topological patterns of GWR during AD pathogenesis and investigated its association with cognitive decline. The study included a cross-sectional dataset and a longitudinal dataset. The cross-sectional dataset included 60 cognitively healthy controls, 61 mild cognitive impairment (MCI), and 63 patients with dementia. The longitudinal dataset included 26 participants who progressed from cognitively normal to dementia and 26 controls that remained cognitively normal. GWR was compared across the cross-sectional groups, adjusted for amyloid PET. The correlation between GWR and cognition performance was also evaluated. The longitudinal dataset was used to investigate GWR alteration during the AD pathogenesis. Dementia with ß-amyloid deposition group exhibited the largest area of increased GWR, followed by MCI with ß-amyloid deposition, MCI without ß-amyloid deposition, and controls. The spatial pattern of GWR-increased regions was not influenced by ß-amyloid deposits. Correlation between regional GWR alteration and cognitive decline was only detected among individuals with ß-amyloid deposition. GWR showed positive correlation with tau PET in the left supramarginal, lateral occipital gyrus, and right middle frontal cortex. The longitudinal study showed that GWR increased around the fusiform, inferior/superior temporal lobe, and entorhinal cortex in MCI and progressed to larger cortical regions after progression to AD. The spatial pattern of GWR-increased regions was independent of ß-amyloid deposits but overlapped with tauopathy. The GWR can serve as a promising biomarker of neurodegeneration in AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Demência , Substância Branca , Humanos , Substância Branca/patologia , Estudos Longitudinais , Estudos Transversais , Placa Amiloide/complicações , Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/patologia , Cognição , Imageamento por Ressonância Magnética , Demência/diagnóstico por imagem , Doença de Alzheimer/patologia , Tomografia por Emissão de Pósitrons , Proteínas tau/metabolismo
10.
Nat Mater ; 22(7): 832-837, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36894772

RESUMO

The scaling of silicon-based transistors at sub-ten-nanometre technology nodes faces challenges such as interface imperfection and gate current leakage for an ultrathin silicon channel1,2. For next-generation nanoelectronics, high-mobility two-dimensional (2D) layered semiconductors with an atomic thickness and dangling-bond-free surfaces are expected as channel materials to achieve smaller channel sizes, less interfacial scattering and more efficient gate-field penetration1,2. However, further progress towards 2D electronics is hindered by factors such as the lack of a high dielectric constant (κ) dielectric with an atomically flat and dangling-bond-free surface3,4. Here, we report a facile synthesis of a single-crystalline high-κ (κ of roughly 16.5) van der Waals layered dielectric Bi2SeO5. The centimetre-scale single crystal of Bi2SeO5 can be efficiently exfoliated to an atomically flat nanosheet as large as 250 × 200 µm2 and as thin as monolayer. With these Bi2SeO5 nanosheets as dielectric and encapsulation layers, 2D materials such as Bi2O2Se, MoS2 and graphene show improved electronic performances. For example, in 2D Bi2O2Se, the quantum Hall effect is observed and the carrier mobility reaches 470,000 cm2 V-1 s-1 at 1.8 K. Our finding expands the realm of dielectric and opens up a new possibility for lowering the gate voltage and power consumption in 2D electronics and integrated circuits.


Assuntos
Grafite , Silício , Eletrônica , Semicondutores
11.
Am J Kidney Dis ; 83(3): 293-305.e1, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37839687

RESUMO

RATIONALE & OBJECTIVE: Head-to-head data comparing the effectiveness and safety of oral anticoagulants in patients with atrial fibrillation (AF) and advanced chronic kidney disease (CKD) are lacking. We compared the safety and effectiveness of warfarin or rivaroxaban versus apixaban in patients with AF and non-dialysis-dependent CKD stage 4/5. STUDY DESIGN: Propensity score-matched cohort study. SETTING & PARTICIPANTS: 2 nationwide US claims databases, Medicare and Optum's deidentified Clinformatics Data Mart Database, were searched for the interval from January 1, 2013, through March 31, 2022, for patients with nonvalvular AF and CKD stage 4/5 who initiated warfarin versus apixaban (matched cohort, n=12,488) and rivaroxaban versus apixaban (matched cohort, n = 5,720). EXPOSURES: Warfarin, rivaroxaban, or apixaban. OUTCOMES: Primary outcomes included major bleeding and ischemic stroke. Secondary outcomes included all-cause mortality, major gastrointestinal bleeding, and intracranial bleeding. ANALYTICAL APPROACH: Cox regression was used to estimate HRs, and 1:1 propensity-score matching was used to adjust for 80 potential confounders. RESULTS: Compared with apixaban, warfarin initiation was associated with a higher rate of major bleeding (HR, 1.85; 95% CI, 1.59-2.15), including major gastrointestinal bleeding (1.86; 1.53-2.25) and intracranial bleeding (2.15; 1.42-3.25). Compared with apixaban, rivaroxaban was also associated with a higher rate of major bleeding (1.69; 1.33-2.15). All-cause mortality was similar for warfarin (1.08; 0.98-1.18) and rivaroxaban (0.94; 0.81-1.10) versus apixaban. Furthermore, no statistically significant differences for ischemic stroke were observed for warfarin (1.14; 0.83-1.57) or rivaroxaban (0.71; 0.40-1.24) versus apixaban, but the CIs were wide. Similar results were observed for warfarin versus apixaban in the positive control cohort of patients with CKD stage 3, consistent with randomized trial findings. LIMITATIONS: Few ischemic stroke events, potential residual confounding. CONCLUSIONS: In patients with AF and advanced CKD, rivaroxaban and warfarin were associated with higher rates of major bleeding compared with apixaban, suggesting a superior safety profile for apixaban in this high-risk population. PLAIN-LANGUAGE SUMMARY: Different anticoagulants have been shown to reduce the risk of stroke in patients with atrial fibrillation, such as warfarin and direct oral anticoagulants like apixaban and rivaroxaban. Unfortunately, the large-scale randomized trials that compared direct anticoagulants versus warfarin excluded patients with advanced chronic kidney disease. Therefore, the comparative safety and effectiveness of warfarin, apixaban, and rivaroxaban are uncertain in this population. In this study, we used administrative claims data from the United States to answer this question. We found that warfarin and rivaroxaban were associated with increased risks of major bleeding compared with apixaban. There were few stroke events, with no major differences among the 3 drugs in the risk of stroke. In conclusion, this study suggests that apixaban has a better safety profile than warfarin and rivaroxaban.


Assuntos
Fibrilação Atrial , AVC Isquêmico , Pirazóis , Insuficiência Renal Crônica , Acidente Vascular Cerebral , Humanos , Idoso , Estados Unidos/epidemiologia , Varfarina/efeitos adversos , Rivaroxabana/efeitos adversos , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/epidemiologia , Estudos de Coortes , Estudos Retrospectivos , Medicare , Anticoagulantes/efeitos adversos , Piridonas/efeitos adversos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Hemorragia Gastrointestinal/induzido quimicamente , Hemorragia Gastrointestinal/complicações , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/induzido quimicamente
12.
Opt Express ; 32(1): 40-51, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175061

RESUMO

We design, fabricate, and demonstrate a low-loss and broadband optical interposer with high misalignment tolerance for large-scale integration of many chips using thermal compression flip-chip bonding. The optical interposer achieves flip-chip integration with photonic integrated circuit die containing evanescent couplers with inter-chip coupling loss of 0.54dB and ±3.53µm 3-dB misalignment tolerance. The loss measurement spectrum indicated wavelength-insensitive loss across O-band and C-band with negligible spectral dependence. Further, we demonstrate 1 to 100 wafer-scale equal power splitting using equal power splitters (EPS) and a path length matching design fabricated using a wafer-scale fabrication technique.

13.
J Org Chem ; 89(10): 7339-7346, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38662477

RESUMO

NHC-catalyzed [4+2] annulation of 2H-azirine-2-carbaldehydes with ketimines and isocyanates has been developed, providing straightforward synthetic protocols for constructing structurally intriguing pyrimido[1,2-a]indolediones and pyrimidinediones under mild conditions with excellent yields. This protocol can be used to synthesize the core skeleton of pharmaceutically important drugs and pyrimido[1,2-a]indoledione-containing natural products, making it potentially valuable for creating biologically active derivatives.

14.
Value Health ; 27(3): 367-375, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38141816

RESUMO

OBJECTIVES: Thyroid cancer incidence increased over 200% from 1992 to 2018, whereas mortality rates had not increased proportionately. The increased incidence has been attributed primarily to the detection of subclinical disease, raising important questions related to thyroid cancer control. We developed the Papillary Thyroid Carcinoma Microsimulation model (PATCAM) to answer them, including the impact of overdiagnosis on thyroid cancer incidence. METHODS: PATCAM simulates individuals from age 15 until death in birth cohorts starting from 1975 using 4 inter-related components, including natural history, detection, post-diagnosis, and other-cause mortality. PATCAM was built using high-quality data and calibrated against observed age-, sex-, and stage-specific incidence in the United States as reported by the Surveillance, Epidemiology, and End Results database. PATCAM was validated against US thyroid cancer mortality and 3 active surveillance studies, including the largest and longest running thyroid cancer active surveillance cohort in the world (from Japan) and 2 from the United States. RESULTS: PATCAM successfully replicated age- and stage-specific papillary thyroid cancers (PTC) incidence and mean tumor size at diagnosis and PTC mortality in the United States between 1975 and 2015. PATCAM accurately predicted the proportion of tumors that grew more than 3 mm and 5 mm in 5 years and 10 years, aligning with the 95% confidence intervals of the reported rates from active surveillance studies in most cases. CONCLUSIONS: PATCAM successfully reproduced observed US thyroid cancer incidence and mortality over time and was externally validated. PATCAM can be used to identify factors that influence the detection of subclinical PTCs.


Assuntos
Carcinoma Papilar , Carcinoma , Neoplasias da Glândula Tireoide , Humanos , Estados Unidos/epidemiologia , Adolescente , Câncer Papilífero da Tireoide/epidemiologia , Carcinoma/diagnóstico , Carcinoma/patologia , Carcinoma Papilar/epidemiologia , Carcinoma Papilar/diagnóstico , Carcinoma Papilar/patologia , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Incidência
15.
Anal Bioanal Chem ; 416(2): 509-518, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37989848

RESUMO

The application of standing surface acoustic wave (SSAW) tweezers based on backpropagation superposition to achieve precise behavior manipulation of microscale cells and even nanoscale bacteria has been widely studied and industrialized. However, the structure requires multiple transducer components or full channel resonance. It is very challenging to design a simple structure for nano-control by complex acoustic field. In this study, a reflector-interdigital transducer (R-IDT) acoustofluidic device based on unilateral coherence enhancement is proposed to achieve SSAW definition features of periodic particle capture positions. The SAW device based on a unilateral transducer can not only generate leaky-SAW in water-filled microchannel, but also have a contribution of spherical waves in the vibration area of the substrate-liquid interface due to the Huygens-Fresnel diffractive principle. Both of them form a robust time-averaged spatial periodicity in the pressure potential gradient, accurately predicting the lateral spacing of these positions through acoustic patterning methods. Furthermore, a reflector based on Bragg-reflection is used to suppress backward transmitted SAW and enhance forward conducted SAW beams. By using a finite element model, R-IDT structure's amplitude enhances 60.78% compared to single IDT structure. The particle manipulation range of the diffractive acoustic field greatly improves, verified by experimental polystyrene microspheres. Besides, biocompatibility is conformed through red blood cells and Bacillus subtilis. We investigate the overall shift of periodic pressure field that can still occur when the phase changes. This work provides a simpler and low-cost solution for the application of acoustic tweezer in biological cell culture and filtering.

17.
J Toxicol Environ Health A ; 87(10): 421-427, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38551405

RESUMO

Vascular dementia (VD) a heterogenous group of brain disorders in which cognitive impairment is attributable to vascular risk factors and cerebrovascular disease. A common phenomenon in VD is a dysfunctional cerebral regulatory mechanism associated with insufficient cerebral blood flow, ischemia and hypoxia. Under hypoxic conditions oxygen supply to the brain results in neuronal death leading to neurodegenerative diseases including Alzheimer's (AD) and VD. In conditions of hypoxia and low oxygen perfusion, expression of hypoxia-inducible factor 1 alpha (HIF-1α) increases under conditions of low oxygen and low perfusion associated with upregulation of expression of hypoxia-upregulated mitochondrial movement regulator (HUMMR), which promotes anterograde mitochondrial transport by binding with trafficking protein kinesin 2 (TRAK2). Schisandrin B (Sch B) an active component derived from Chinese herb Wuweizi prevented ß-amyloid protein induced morphological alterations and cell death using a SH-SY5Y neuronal cells considered an AD model. It was thus of interest to determine whether Sch B might also alleviate VD using a rat bilateral common carotid artery occlusion (BCAO) dementia model. The aim of this study was to examine the effects of Sch B in BCAO on cognitive functions such as Morris water maze test and underlying mechanisms involving expression of HIF-1α, TRAK2, and HUMMR levels. The results showed that Sch B improved learning and memory function of rats with VD and exerted a protective effect on the hippocampus by inhibition of protein expression of HIF-1α, TRAK2, and HUMMR factors. Evidence indicates that Sch B may be considered as an alternative in VD treatment.


Assuntos
Demência Vascular , Lignanas , Neuroblastoma , Compostos Policíclicos , Ratos , Humanos , Animais , Demência Vascular/tratamento farmacológico , Demência Vascular/etiologia , Demência Vascular/metabolismo , Aprendizagem em Labirinto/fisiologia , Hipóxia , Cognição , Hipocampo , Oxigênio/farmacologia , Ciclo-Octanos
18.
BMC Public Health ; 24(1): 1852, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992625

RESUMO

BACKGROUND: The growing prevalence of non-alcoholic fatty liver disease (NAFLD) in younger populations, particularly those of working age (15-64 years), has become a public health concern. Being diagnosed at a younger age implies a greater likelihood of accruing disability-adjusted life years (DALYs) later in life due to potential progression to conditions such as cirrhosis or hepatocellular carcinoma. This study aims to analyze NAFLD prevalence trends over three decades globally, regionally, and nationally, with a focus on age, period, and birth cohort associations. METHODS: Global, regional, and country time trends in the prevalence of NAFLD among working-age people from 1990 to 2019: Age-period-cohort analysis based on Global Burden of Disease Study 2019 estimates and 95% uncertainty interval (UI) of NAFLD prevalence in the working age population was extracted from the Global Burden of Diseases, Injuries and Risk Factors Study 2019. Age-period-cohort models were used to estimate the prevalence within each age group from 1990 to 2019 (local drift, % per year), fitted longitudinal age-specific rates adjusted for period bias (age effect), and period/cohort relative risk (period/cohort effect). RESULTS: The global age-standardized prevalence (ASPR) of NAFLD increased significantly from 1990 (14,477.6 per 100 000) to 2019 (19,837.6 per 100 000). In the Western Pacific, there were 42,903.8 NAFLD cases in 2019, 54.15% higher than in 1990. The ASPR also increased significantly in the region over the past three decades. At the national level, Palau had the highest ASPR while Brunei Darussalam had the lowest. Age-period-cohort analysis showed that in the Western Pacific, unlike globally, the risk of NAFLD declined after age 60-64 years. Relative to 1980-1989, incidence and DALY risks decreased but prevalence increased in subsequent birth cohorts. Future predictions indicate an upward trend in NAFLD burden, especially among women and medium (SDI) regions like China. CONCLUSION: Non-alcoholic fatty liver disease imparts an immense health burden that continues to grow globally and in the Asia Pacific region. Our work highlights working age adults as an at-risk group and calls attention to socioeconomic gradients within Western Pacific countries. Upward future projections demonstrate that NAFLD prevention is an urgent priority.


Assuntos
Carga Global da Doença , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Pessoa de Meia-Idade , Adulto , Carga Global da Doença/tendências , Feminino , Masculino , Adulto Jovem , Adolescente , Prevalência , Estudos de Coortes , Fatores de Risco , Anos de Vida Ajustados por Deficiência
19.
Ecotoxicol Environ Saf ; 270: 115894, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38171100

RESUMO

Algal toxins produced by microalgae, such as domoic acid (DA)1, have toxic effects on humans. However, toxicity tests using mice only yield lethal doses of algal toxins without providing insights into the mechanism of action on cells. In this study, a fast segmentation of microfluidic flow cytometry cell images based on the bidirectional background subtraction (BBS)2 method was developed to get the visual evidence of apoptosis in both bright-field and fluorescence images. This approach enables mapping of changes in cell morphology and activity under algal toxins, allowing for fast (within 60 s) and automated biological detection. By combining microfluidics with flow cytometry, the intricate cellular-level reaction process can be observed in micro samples of 293 T cells and mouse spleen cells, offering potential for future in vitro experiments.


Assuntos
Microalgas , Microfluídica , Humanos , Animais , Camundongos , Citometria de Fluxo
20.
Environ Toxicol ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530049

RESUMO

BACKGROUND: Melanoma, the most lethal form of skin cancer, presents substantial challenges despite effective surgical interventions for in situ lesions. Regulatory T cells (Tregs) wield a pivotal immunomodulatory influence within the tumor microenvironment, yet their impact on melanoma prognosis and direct molecular interactions with melanoma cells remain elusive. This investigation employs single-cell analysis to unveil the intricate nature of Tregs in human melanoma. METHODS: Single-cell RNA and bulk sequencing data, alongside clinical information, were obtained from public repositories. Initially, GO and GSEA analyses were employed to delineate functional disparities among distinct cell subsets. Pseudotime and cell-cell interconnection analyses were conducted, followed by an endeavor to construct a prognostic model grounded in Treg-associated risk scores. This model's efficacy was demonstrated via PCA and K-M analyses, with multivariate Cox regression affirming its independent prognostic value in melanoma patients. Furthermore, immune infiltration analysis, immune checkpoint gene expression scrutiny, and drug sensitivity assessments were performed to ascertain the clinical relevance of this prognostic model. RESULTS: Following batch effect correction, 80 025 cells partitioned into 31 clusters, encompassing B cells, plasma cells, endothelial cells, fibroblasts, melanoma cells, monocytes, macrophages, and T_NK cells. Within these, 4240 CD4+ T cells were subclassified into seven distinct types. Functional analysis underscored the immunomodulatory function of Tregs within the melanoma tumor microenvironment, elucidating disparities among Treg subpopulations. Notably, the ITGB2 signaling pathway emerged as a plausible molecular nexus linking Tregs to melanoma cells. Our prognostic signature exhibited robust predictive capacities for melanoma prognosis and potential implications in evaluating immunotherapy response. CONCLUSION: Tregs exert a critical role in immune suppression within the melanoma tumor microenvironment, revealing a potential molecular-level association with melanoma cells. Our innovative Treg-centered signature introduces a promising prognostic marker for melanoma, holding potential for future clinical prognostic assessments.

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