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1.
Phys Chem Chem Phys ; 26(36): 23998-24007, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39246281

RESUMEN

Janus TiPX (X = F, Cl, and Br) monolayers were systematically investigated through first-principles calculations. The Janus TiPX monolayers exhibit mechanical and dynamic stability. Two monolayers are indirect bandgap semiconductors, except the TiPBr monolayer, which has the features of a quasi-direct bandgap semiconductor. Biaxial strain can modify the band gap of single layers. The Janus TiPX monolayers have remarkable flexibility and piezoelectric properties. In particular, the TiPF monolayer shows high horizontal (44.18 pm V-1) and vertical piezoelectric coefficients (-3.59 pm V-1). These values exceed those of conventional bulk materials, like GaN (3.1 pm V-1) and α-quartz (2.3 pm V-1). All of the monolayers have absorption coefficients of 105 cm-1 for visible and ultraviolet (UV) light, which are one order of magnitude greater than that of MoSSe. Furthermore, TiPX monolayers have high carrier mobility. Janus TiPX monolayers represent a class of two-dimensional (2D) materials with exceptional properties and multifunctionality, holding significant promise for various applications in piezoelectric sensors, solar cells, and nano-electronic devices.

2.
Opt Lett ; 49(18): 5107-5110, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39270241

RESUMEN

A photonic approach for generating and programmable switching variable-band chirped waveforms by using a dual-parallel Mach-Zehnder modulator (DPMZM) is proposed and experimentally demonstrated. By coupling binary switching codes with the baseband chirped signal and applying them into the RF input port of DPMZM, the variable-band chirped waveforms can be generated and fast switched. The switching speed is consistent with the input code bit rate. Moreover, by properly adjusting the bias voltages, the generated signals can be anti-dispersion transmitted over different distances. Full experimental verification on the generation and programmable switching of the chirped waveforms centered at 2.1, 6.3, and 8.4 GHz or 1.5, 4.5, and 6 GHz over 10 or 20 km standard single-mode fibers with 4 or 100 Mbps switching rates are successfully carried out. The proposed approach features compact architecture, programmable switching capability and immunity to power fading, which are significant in distributed multifunction radar networks with optical fiber-based transmission.

3.
Phytochemistry ; 228: 114241, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39122160

RESUMEN

Six pairs of previously undescribed enantiomeric phytocannabinoid-like meroterpenoids, (±)-spinulinoids A‒F, and two naturally occurring compounds, (+)-rhododaurichromanic acid A and (E)-4-((3,7-dimethylocta-2,6-dien-1-yl)oxy)benzoic acid, together with one known congener, (-)-rhododaurichromanic acid A, were obtained from the twigs and leaves of Rhododendron spinuliferum. Their structures were established by their extensive spectral data (NMR and HRESIMS), ECD calculations, and single-crystal X-ray diffraction data. Spinulinoids A and B are unprecedented phytocannabinoid-like meroterpenoids constructed by the resorcinol moiety and a ß-bisabolene unit, whereas spinulinoid C represents a rare adduct of quinone and ß-bisabolene with a tricyclic 6/6/6 ring system.


Asunto(s)
Hojas de la Planta , Rhododendron , Terpenos , Rhododendron/química , Hojas de la Planta/química , Terpenos/química , Terpenos/aislamiento & purificación , Estructura Molecular , Modelos Moleculares , Conformación Molecular , Cristalografía por Rayos X
4.
Phytochemistry ; 228: 114254, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39159738

RESUMEN

Four previously undescribed phloroglucinols, including three pairs of enantiomers, (±)-rhodotomentodimer F, (±)-rhodotomentodimer G, and (±)-rhodotomentomonomer E, and one phloroglucinol-sesquiterpene meroterpenoid, rhodotomentodione E, together with one previously reported congener, (±)-rhodomyrtosone A, were obtained from the leaves of Rhodomyrtus tomentosa. The structures including absolute configurations of previously undescribed isolates were elucidated by extensive spectroscopic analysis (HRESIMS and NMR), ECD calculations, and single-crystal X-ray diffraction. (±)-Rhodotomentodimer F is a rare phloroglucinol derivative conjugated by a ß-triketone moiety and an unprecedented resorcinol unit via the formation of a rare bis-furan ring system, whereas (±)-rhodotomentomonomer E shares a rearranged pentacyclic scaffold. Pharmacologically, (±)-rhodotomentomonomer E showed the strongest human acetylcholinesterase (hAChE) inhibitory effect with an IC50 value of 1.04 ± 0.05 µM. Molecular formula studies revealed that hydrogen bonds formed between hAChE residues Glu202, Ser203, Ala204, Gly121, Gly122, Tyr337, and His447 and (±)-rhodotomentomonomer E played crucial roles in its observed activity. These findings indicated that the leaves of Rhodomyrtus tomentosa can supply a rich source of hAChE inhibitors. These inhibitors might potentially be utilized in the therapeutic strategy for Alzheimer's disease, offering promising candidates for further research and development.


Asunto(s)
Acetilcolinesterasa , Inhibidores de la Colinesterasa , Myrtaceae , Floroglucinol , Floroglucinol/química , Floroglucinol/farmacología , Floroglucinol/aislamiento & purificación , Myrtaceae/química , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/aislamiento & purificación , Acetilcolinesterasa/metabolismo , Acetilcolinesterasa/efectos de los fármacos , Humanos , Estructura Molecular , Hojas de la Planta/química , Relación Estructura-Actividad , Modelos Moleculares
5.
JAMA Netw Open ; 7(6): e2416088, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38861258

RESUMEN

Importance: Several clinical practice guidelines advise race- and ethnicity-based screening for youth-onset type 2 diabetes (T2D) due to a higher prevalence among American Indian and Alaska Native, Asian, Black, and Hispanic youths compared with White youths. However, rather than a biological risk, this disparity likely reflects the inequitable distribution of adverse social determinants of health (SDOH), a product of interpersonal and structural racism. Objective: To evaluate prediabetes prevalence by presence or absence of adverse SDOH in adolescents eligible for T2D screening based on weight status. Design, Setting, and Participants: This cross-sectional study and analysis used data from the 2011 to 2018 cycles of the National Health and Nutrition Examination Survey. Data were analyzed from June 1, 2023, to April 5, 2024. Participants included youths aged 12 to 18 years with body mass index (BMI) at or above the 85th percentile without known diabetes. Main Outcomes and Measures: The main outcome consisted of an elevated hemoglobin A1c (HbA1c) level greater than or equal to 5.7% (prediabetes or undiagnosed presumed T2D). Independent variables included race, ethnicity, and adverse SDOH (food insecurity, nonprivate health insurance, and household income <130% of federal poverty level). Survey-weighted logistic regression was used to adjust for confounders of age, sex, and BMI z score and to determine adjusted marginal prediabetes prevalence by race, ethnicity, and adverse SDOH. Results: The sample included 1563 individuals representing 10 178 400 US youths aged 12 to 18 years (mean age, 15.5 [95% CI, 15.3-15.6] years; 50.5% [95% CI, 47.1%-53.9%] female; Asian, 3.0% [95% CI, 2.2%-3.9%]; Black, 14.9% [95% CI, 11.6%-19.1%]; Mexican American, 18.8% [95% CI, 15.4%-22.9%]; Other Hispanic, 8.1% [95% CI, 6.5%-10.1%]; White, 49.1% [95% CI, 43.2%-55.0%]; and >1 or other race, 6.1% [95% CI, 4.6%-8.0%]). Food insecurity (4.1% [95% CI, 0.7%-7.5%]), public insurance (5.3% [95% CI, 1.6%-9.1%]), and low income (5.7% [95% CI, 3.0%-8.3%]) were each independently associated with higher prediabetes prevalence after adjustment for race, ethnicity, and BMI z score. While Asian, Black, and Hispanic youths had higher prediabetes prevalence overall, increasing number of adverse SDOH was associated with higher prevalence among White youths (8.3% [95% CI, 4.9%-11.8%] for 3 vs 0.6% [95% CI, -0.7% to 2.0%] for 0 adverse SDOH). Conclusions and Relevance: Adverse SDOH were associated with higher prediabetes prevalence, across and within racial and ethnic categories. Consideration of adverse SDOH may offer a more actionable alternative to race- and ethnicity-based screening to evaluate T2D risk in youth.


Asunto(s)
Diabetes Mellitus Tipo 2 , Estado Prediabético , Determinantes Sociales de la Salud , Adolescente , Niño , Femenino , Humanos , Masculino , Índice de Masa Corporal , Estudios Transversales , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/etnología , Etnicidad/estadística & datos numéricos , Inseguridad Alimentaria , Hemoglobina Glucada/análisis , Encuestas Nutricionales , Estado Prediabético/epidemiología , Estado Prediabético/etnología , Prevalencia , Determinantes Sociales de la Salud/estadística & datos numéricos , Estados Unidos/epidemiología , Indio Americano o Nativo de Alaska , Asiático , Negro o Afroamericano , Hispánicos o Latinos , Blanco
6.
Int J Biol Macromol ; 274(Pt 2): 133508, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38944067

RESUMEN

Agave species are typical crassulacean acid metabolism (CAM) plants commonly cultivated to produce beverages, fibers, and medicines. To date, few studies have examined hemicellulose biosynthesis in Agave H11648, which is the primary cultivar used for fiber production. We conducted PacBio sequencing to obtain full-length transcriptome of five agave tissues: leaves, shoots, roots, flowers, and fruits. A total of 41,807 genes were generated, with a mean length of 2394 bp and an annotation rate of 97.12 % using public databases. We identified 42 glycosyltransferase genes related to hemicellulose biosynthesis, including mixed-linkage glucan (1), glucomannan (5), xyloglucan (16), and xylan (20). Their expression patterns were examined during leaf development and fungal infection, together with hemicellulose content. The results revealed four candidate glycosyltransferase genes involved in xyloglucan and xylan biosynthesis, including glucan synthase (CSLC), xylosyl transferase (XXT), xylan glucuronyltransferase (GUX), and xylan α-1,3-arabinosyltransferase (XAT). These genes can be potential targets for manipulating xyloglucan and xylan traits in agaves, and can also be used as candidate enzymatic tools for enzyme engineering. We have provided the first full-length transcriptome of agave, which will be a useful resource for gene identification and characterization in agave species. We also elucidated the hemicellulose biosynthesis machinery, which will benefit future studies on hemicellulose traits in agave.


Asunto(s)
Agave , Regulación de la Expresión Génica de las Plantas , Glicosiltransferasas , Polisacáridos , Transcriptoma , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Agave/genética , Polisacáridos/biosíntesis , Xilanos/metabolismo , Xilanos/biosíntesis , Perfilación de la Expresión Génica , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
Med Oncol ; 41(6): 140, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713310

RESUMEN

Glioblastoma (GBM) is an extremely aggressive primary brain tumor with poor prognosis, short survival time post-diagnosis and high recurrence. Currently, no cure for GBM exists. The identification of an effective therapeutic modality for GBM remains a high priority amongst medical professionals and researches. In recent studies, inhalant cannabidiol (CBD) has demonstrated promise in effectively inhibiting GBM tumor growth. However, exactly how CBD treatment affects the physiology of these tumor cells remains unclear. Stress granules (SG) (a sub-class of biomolecular condensates (BMC)) are dynamic, membrane-less intracellular microstructures which contain proteins and nucleic acids. The formation and signaling of SGs and BMCs plays a significant role in regulating malignancies. This study investigates whether inhaled CBD may play an intervening role towards SGs in GBM tumor cells. Integrated bioinformatics approaches were preformed to gain further insights. This includes use of Immunohistochemistry and flow cytometry to measure SGs, as well as expression and phosphorylation of eukaryotic initiation factor-2α (eIF2α). The findings of this study reveal that CBD receptors (and co-regulated genes) have the potential to play an important biological role in the formation of BMCs within GBM. In this experiment, CBD treatment significantly increased the volume of TIAR-1. This increase directly correlated with elevation in both eIF2α expression and p-eIF2α in CBD treated tissues in comparison to the placebo group (p < 0.05). These results suggest that inhalant CBD significantly up-regulated SGs in GBM, and thus support a theory of targeting BMCs as a potential therapeutic substrate for treating GBM.


Asunto(s)
Neoplasias Encefálicas , Cannabidiol , Glioblastoma , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patología , Cannabidiol/farmacología , Humanos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Gránulos de Estrés/metabolismo , Gránulos de Estrés/efectos de los fármacos , Línea Celular Tumoral , Factor 2 Eucariótico de Iniciación/metabolismo
8.
J Hazard Mater ; 472: 134549, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38733789

RESUMEN

Selenium nanoparticles (SeNPs) has been reported as a beneficial role in alleviating cadmium (Cd) toxicity in plant. However, underlying molecular mechanisms about SeNPs reducing Cd accumulation and alleviating Cd toxicity in wheat are not well understood. A hydroponic culture was performed to evaluate Cd and Se accumulation, cell wall components, oxidative stress and antioxidative system, and transcriptomic response of wheat seedlings after SeNPs addition under Cd stress. Results showed that SeNPs application notably reduced Cd concentration in root and in shoot by 56.9% and 37.3%, respectively. Additionally, SeNPs prompted Cd distribution in root cell wall by 54.7%, and increased lignin, pectin and hemicellulose contents by regulating cell wall biosynthesis and metabolism-related genes. Further, SeNPs alleviated oxidative stress caused by Cd in wheat through signal transduction pathways. We also observed that Cd addition reduced Se accumulation by downregulating the expression level of aquaporin 7. These results indicated that SeNPs alleviated Cd toxicity and reduced Cd accumulation in wheat, which were associated with the synergetic regulation of cell wall biosynthesis pathway, uptake transporters, and antioxidative system via signaling pathways.


Asunto(s)
Cadmio , Pared Celular , Selenio , Transcriptoma , Triticum , Triticum/efectos de los fármacos , Triticum/metabolismo , Pared Celular/efectos de los fármacos , Pared Celular/metabolismo , Cadmio/toxicidad , Selenio/farmacología , Selenio/química , Transcriptoma/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Nanopartículas/toxicidad , Nanopartículas/química , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Nanopartículas del Metal/toxicidad , Nanopartículas del Metal/química , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Contaminantes del Suelo/toxicidad
9.
J Agric Food Chem ; 72(19): 10970-10980, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38708787

RESUMEN

Eleven alkaloids (1-11) including seven new ones, 1-7, were isolated from the solid fermentation of Aspergillus fumigatus VDL36, an endophytic fungus isolated from the leaves of Vaccinium dunalianum Wight (Ericaceae), a perennial evergreen shrub distributed across the Southwest regions of China, Myanmar, and Vietnam. Their structures were elucidated on the basis of extensive spectroscopic methods. The isolates were evaluated for in vitro antifungal activities against five phytopathogenic fungi (Fusarium oxysporum, Coriolus versicolor, Fusarium solani, Botrytis cinerea, Fusarium graminearum). As a result, the new compounds fumigaclavine I (1), 13-ethoxycyclotryprostatin A (5), 13-dehydroxycyclotryprostatin A (6), and 12ß-hydroxy-13-oxofumitremorgin C (7) exhibited antifungal activities with MIC values of 7.8-62.5 µg/mL which were comparable to the two positive controls ketoconazole (MIC = 7.8-31.25 µg/mL) and carbendazim (MIC = 1.95-7.8 µg/mL). Furthermore, compounds 1 and 5 demonstrated potent protective and curative effects against the tomato gray mold in vivo. Preliminary structure-activity relationships of the tested indole diketopiperazine alkaloids indicate that the introduction of a substituent group at position C-13 enhances their biological activities.


Asunto(s)
Alcaloides , Aspergillus fumigatus , Endófitos , Alcaloides/farmacología , Alcaloides/química , Aspergillus fumigatus/efectos de los fármacos , Endófitos/química , Estructura Molecular , Fusarium/efectos de los fármacos , Fungicidas Industriales/farmacología , Fungicidas Industriales/química , Hojas de la Planta/microbiología , Hojas de la Planta/química , Pruebas de Sensibilidad Microbiana , China , Enfermedades de las Plantas/microbiología
10.
J Sci Food Agric ; 104(9): 4977-4988, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38567804

RESUMEN

BACKGROUND: As the major protein (approximately 36%) in rice bran, globulin exhibits excellent foaming and emulsifying properties, endowing its useful application as a foaming and emulsifying agent in the food industry. However, the low water solubility restricts its commercial potential in industrial applications. The present study aimed to improve this protein's processing and functional properties. RESULTS: A novel covalent complex was fabricated by a combination of the Maillard reaction and alkaline oxidation using rice bran globulin (RBG), chitooligosaccharide (C), quercetin (Que) and resveratrol (Res). The Maillard reaction improved the solubility, emulsifying and foaming properties of RBG. The resultant glycosylated protein was covalently bonded with quercetin and resveratrol to form a (RBG-C)-Que-Res complex. (RBG-C)-Que-Res exhibited higher thermal stability and antioxidant ability than the native protein, binary globulin-chitooligosaccharide or ternary globulin-chitooligosaccharide-polyphenol (only containing quercetin or resveratrol) conjugates. (RBG-C)-Que-Res exerted better cytoprotection against the generation of malondialdehyde and reactive oxygen species in HepG2 cells, which was associated with increased activities of antioxidative enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) through upregulated genes SOD1, CAT, GPX1 (i.e. gene for glutathione peroxidase-1), GCLM (i.e. gene for glutamate cysteine ligase modifier subunit), SLC1A11 (i.e. gene for solute carrier family 7, member 11) and SRXN1 (i.e. gene for sulfiredoxin-1). The anti-apoptotic effect of (RBG-C)-Que-Res was confirmed by the downregulation of caspase-3 and p53 and the upregulation of B-cell lymphoma-2 gene expression. CONCLUSION: The present study highlights the potential of (RBG-C)-Que-Res conjugates as functional ingredients in healthy foods. © 2024 Society of Chemical Industry.


Asunto(s)
Antioxidantes , Quitosano , Oligosacáridos , Oryza , Quercetina , Resveratrol , Humanos , Quercetina/química , Quercetina/análogos & derivados , Oryza/química , Oligosacáridos/química , Resveratrol/química , Resveratrol/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Quitosano/química , Células Hep G2 , Quitina/química , Quitina/análogos & derivados , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Reacción de Maillard , Catalasa/metabolismo , Catalasa/genética , Glutatión Peroxidasa/metabolismo , Glutatión Peroxidasa/genética
11.
Biosens Bioelectron ; 254: 116201, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38507928

RESUMEN

Developing highly sensitive and selective methods that incorporate specific recognition elements is crucial for detecting small molecules because of the limited availability of small molecule antibodies and the challenges in obtaining sensitive signals. In this study, a generalizable photoelectrochemical-colorimetric dual-mode sensing platform was constructed based on the synergistic effects of a molecularly imprinted polymer (MIP)-aptamer sandwich structure and nanoenzymes. The MIP functionalized peroxidase-like Fe3O4 (Fe3O4@MIPs) and alkaline phosphatase mimic Zr-MOF labeled aptamer (Zr-mof@Apt) were used as the recognition elements. By selectively accumulating dibutyl phthalate (DBP), a small molecule target model, on Fe3O4@MIPs, the formation of Zr-MOF@Apt-DBP- Fe3O4@MIPs sandwich structure was triggered. Fe3O4@MIPs oxidized TMB to form blue-colored oxTMB. However, upon selective accumulation of DBP, the catalytic activity of Fe3O4@MIPs was inhibited, resulting in a lighter color that was detectable by the colorimetric method. Additionally, Zr-mof@Apt effectively catalyzed the hydrolysis of L-Ascorbic acid 2-phosphate sesquimagnesium salt hydrate (AAPS), generating ascorbic acid (AA) that could neutralize the photogenerated holes to decrease the photocurrent signals for PEC sensing and reduce oxTMB for colorimetric testing. The dual-mode platform showed strong linearity for different concentrations of DBP from 1.0 pM to 10 µM (PEC) and 0.1 nM to 0.5 µM (colorimetry). The detection limits were 0.263 nM (PEC) and 30.1 nM (colorimetry) (S/N = 3), respectively. The integration of dual-signal measurement mode and sandwich recognition strategy provided a sensitive and accurate platform for the detection of small molecules.


Asunto(s)
Técnicas Biosensibles , Polímeros Impresos Molecularmente , Colorimetría/métodos , Peroxidasa/química , Peroxidasas
13.
Int J Clin Oncol ; 29(5): 592-601, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38514497

RESUMEN

BACKGROUND: In the era of combination therapy, there has been limited research on body composition. Specific body composition, such as sarcopenia, possesses the potential to serve as a predictive biomarker for toxic effects and clinical response in patients with urothelial carcinoma (UC) undergoing tislelizumab combined with gemcitabine and cisplatin (T + GC). MATERIALS AND METHODS: A total of 112 UC patients who received T + GC were selected at the Affiliated Hospital of Xuzhou Medical University from April 2020 to January 2023. Baseline patient characteristics and detailed hematological parameters were collected using the electronic medical system and laboratory examinations. The computed tomography images of patients were analyzed to calculate psoas muscle mass index (PMI). We evaluated the association between sarcopenia (PMI < 4.5 cm2/m2 in men; PMI < 3.3 cm2/m2 in women) and both hematological toxicity and tumor response. RESULTS: Overall, of the 112 patients (65.2% male, median age 56 years), 43 (38.4%) were defined as sarcopenia. Patients with sarcopenia were notably older (p = 0.037), more likely to have hypertension (p = 0.009), and had poorer ECOG-PS (p = 0.027). Patients with sarcopenia were more likely to develop leukopenia (OR 2.969, 95% CI 1.028-8.575, p = 0.044) after receiving at least two cycles of T + GC. However, these significant differences were not observed in thrombocytopenia and anemia. There were no significant differences in the tumor response and grade 3-4 hematological toxicity between patients with sarcopenia and those without sarcopenia. CONCLUSIONS: Patients with sarcopenia were more likely to develop leukopenia after receiving T + GC. There were no notable alterations observed in relation to anemia or thrombocytopenia. No significant difference was found between the sarcopenia group and non-sarcopenia group in terms of tumor response and grade 3-4 hematological toxicity.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Cisplatino , Desoxicitidina , Gemcitabina , Leucopenia , Sarcopenia , Humanos , Masculino , Femenino , Persona de Mediana Edad , Sarcopenia/inducido químicamente , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Cisplatino/uso terapéutico , Leucopenia/inducido químicamente , Desoxicitidina/análogos & derivados , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Anciano , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/uso terapéutico , Estudios Retrospectivos , Carcinoma de Células Transicionales/tratamiento farmacológico , Carcinoma de Células Transicionales/complicaciones , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/complicaciones , Adulto , Neoplasias Urológicas/tratamiento farmacológico , Neoplasias Urológicas/complicaciones , Neoplasias Urológicas/patología
14.
Angew Chem Int Ed Engl ; 63(18): e202401949, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38437064

RESUMEN

X-ray scintillators have gained significant attention in medical diagnostics and industrial applications. Despite their widespread utility, scintillator development faces a significant hurdle when exposed to elevated temperatures, as it usually results in reduced scintillation efficiency and diminished luminescence output. Here we report a molecular design strategy based on a hybrid perovskite (TpyBiCl5) that overcomes thermal quenching through multi-excited state switching. The structure of perovskite provides a platform to modulate the luminescence centers. The rigid framework constructed by this perovskite structure stabilized its triplet states, resulting in TpyBiCl5 exhibiting an approximately 12 times higher (45 % vs. 3.8 %) photoluminescence quantum yield of room temperature phosphorescence than that of its organic ligand (Tpy). Most importantly, the interactions between the components of this perovskite enable the mixing of different excited states, which has been revealed by experimental and theoretical investigations. The TpyBiCl5 scintillator exhibits a detection limit of 38.92 nGy s-1 at 213 K and a detection limit of 196.31 nGy s-1 at 353 K through scintillation mode switching between thermally activated delayed fluorescence and phosphorescence. This work opens up the possibility of solving the thermal quenching in X-ray scintillators by tuning different excited states.

15.
BMC Oral Health ; 24(1): 69, 2024 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-38200461

RESUMEN

OBJECTIVES: To evaluate the histological parameters and bone mechanical properties around implants with low primary stability (PS) in grafted bone substitutes within an oversized osteotomy. MATERIALS AND METHODS: An oversized osteotomy penetrating the double cortical bone layers was made on both femora of 24 New Zealand white rabbits. Bilaterally in the femur of all animals, 48 implants were installed, subdivided into four groups, corresponding to four prepared tissue-engineering bone complexes (TEBCs), which were placed between the implant surface and native bone wall: A: tricalcium phosphate ß (TCP-ß); B: autologous adipose derived-stem cells with TCP-ß (ASCs/TCP-ß); C: ASCs transfected with the enhanced-GFP gene with TCP-ß (EGFP-ASCs/TCP-ß); D: ASCs transfected with the BMP-2 gene with TCP-ß (BMP2-ASCs/TCP-ß). Trichrome fluorescent labeling was conducted. Animals were sacrificed after eight weeks. The trichromatic fluorescent labeling (%TFL), area of new bone (%NB), residual material (%RM), bone-implant contact (%BIC), and the removal torque force (RTF, N/cm) were assessed. RESULTS: ASCs were successfully isolated from adipose tissue, and the primary ASCs were induced into osteogenic, chondrogenic, and adipogenic differentiation. The BMP-2 overexpression of ASCs sustained for ten days and greatly enhanced the expression of osteopontin (OPN). At eight weeks post-implantation, increased %NB and RTF were found in all groups. The most significant value of %TFL, %BIC and lowest %RM was detected in group D. CONCLUSION: The low PS implants osseointegrate with considerable new bone in grafted TEBCs within an oversized osteotomy. Applying BMP-2 overexpressing ASCs-based TEBC promoted earlier osseointegration and more solid bone mechanical properties on low PS implants. Bone graft offers a wedging effect for the implant with low PS at placement and promotes osteogenesis on their surface in the healing period.


Asunto(s)
Sustitutos de Huesos , Fosfatos de Calcio , Implantes Dentales , Animales , Conejos , Oseointegración , Osteotomía , Osteogénesis , Colorantes
16.
J Agric Food Chem ; 72(3): 1768-1778, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38217861

RESUMEN

To reduce the health risks of exposure to Cd and Pb in wheat, a field experiment was conducted to investigate the differences in Cd and Pb bioaccessibility among the grains of 11 wheat cultivars and their relationships with the nutrient compositions of grains. The grain concentrations (Cd: 0.14-0.56 mg kg-1, Pb: 0.08-0.39 mg kg-1) and bioaccessibility (5.28-57.43% and 0.72-7.72% for Cd and Pb in the intestinal phase, respectively) of Cd and Pb differed significantly among the 11 cultivars. A safe wheat cultivar (Shannong16) with a relatively low health risk and the lowest grain Cd and Pb concentrations was selected. Ca, Mg, phytate, and methionine played key roles in affecting Cd and Pb bioaccessibility in wheat, with Ca and phytate significantly negatively correlated with Cd and Pb bioaccessibility. These findings can be used to optimize the selection strategy for safe wheat cultivars for healthy grain production in Cd-polluted farmland.


Asunto(s)
Cadmio , Contaminantes del Suelo , Cadmio/análisis , Triticum , Plomo , Ácido Fítico , Contaminantes del Suelo/análisis , Nutrientes , Grano Comestible/química , Suelo
17.
Behav Res Methods ; 56(3): 1314-1334, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37845423

RESUMEN

Research questions regarding how, for whom, and where a treatment achieves its effect on an outcome have become increasingly valued in substantive research. Such questions can be answered by causal moderated mediation analysis, which assesses the heterogeneity of the mediation mechanism underlying the treatment effect across individual and contextual characteristics. Various moderated mediation analysis methods have been developed under the traditional path analysis/structural equation modeling framework. One challenge is that the definitions of moderated mediation effects depend on statistical models of the mediator and the outcome, and no solutions have been provided when either the mediator or the outcome is binary, or when the mediator or outcome model is nonlinear. In addition, it remains unclear to empirical researchers how to make causal arguments of moderated mediation effects due to a lack of clarifications of the underlying assumptions and methods for assessing the sensitivity to violations of the assumptions. This article overcomes the limitations by developing general definition, identification, estimation, and sensitivity analysis for causal moderated mediation effects under the potential outcomes framework. We also developed a user-friendly R package moderate.mediation ( https://cran.r-project.org/web/packages/moderate.mediation/index.html ) that allows applied researchers to easily implement the proposed methods and visualize the initial analysis results and sensitivity analysis results. We illustrated the application of the proposed methods and the package implementation with a re-analysis of the National Evaluation of Welfare-to-Work Strategies (NEWWS) Riverside data.


Asunto(s)
Modelos Estadísticos , Programas Informáticos , Humanos , Causalidad
18.
Behav Res Methods ; 56(3): 1738-1769, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37231326

RESUMEN

When designing a study for causal mediation analysis, it is crucial to conduct a power analysis to determine the sample size required to detect the causal mediation effects with sufficient power. However, the development of power analysis methods for causal mediation analysis has lagged far behind. To fill the knowledge gap, I proposed a simulation-based method and an easy-to-use web application ( https://xuqin.shinyapps.io/CausalMediationPowerAnalysis/ ) for power and sample size calculations for regression-based causal mediation analysis. By repeatedly drawing samples of a specific size from a population predefined with hypothesized models and parameter values, the method calculates the power to detect a causal mediation effect based on the proportion of the replications with a significant test result. The Monte Carlo confidence interval method is used for testing so that the sampling distributions of causal effect estimates are allowed to be asymmetric, and the power analysis runs faster than if the bootstrapping method is adopted. This also guarantees that the proposed power analysis tool is compatible with the widely used R package for causal mediation analysis, mediation, which is built upon the same estimation and inference method. In addition, users can determine the sample size required for achieving sufficient power based on power values calculated from a range of sample sizes. The method is applicable to a randomized or nonrandomized treatment, a mediator, and an outcome that can be either binary or continuous. I also provided sample size suggestions under various scenarios and a detailed guideline of app implementation to facilitate study designs.


Asunto(s)
Aplicaciones Móviles , Humanos , Tamaño de la Muestra , Simulación por Computador , Causalidad , Negociación
19.
Cancer Med ; 12(24): 22071-22080, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38093592

RESUMEN

PURPOSE: Whether the addition of tislelizumab to gemcitabine and cisplatin (GC) chemotherapy increases the incidence of myelosuppression has not been well established. This study identified the risk factors for the development of myelosuppression in patients with urothelial carcinoma (UC) after receiving GC chemotherapy with or without tislelizumab. MATERIALS AND METHODS: We enrolled 192 UC patients who received GC with or without tislelizumab at the Affiliated Hospital of Xuzhou Medical University between July 2014 and November 2022. Patient baseline characteristics were included in the statistical analyses after adjusting for previously reported risk factors affecting survival using propensity score matching (1:1). Binary logistic regression analysis was used to identify the risk factors associated with posttreatment myelosuppression. RESULTS: A total of 192 patients were enrolled, of whom 96 were treated with tislelizumab plus gemcitabine and cisplatin (T + GC) and 96 with GC alone. The incidence of leukopenia, anemia, and thrombocytopenia of any grade was 50.0%, 70.8%, and 42.7%, respectively, in the T + GC group and 41.7%, 72.9%, and 20.8%, respectively, in the GC group. In multivariate analysis, patients aged over 70 years (OR = 2.486, 95% CI: 1.067-5.792, p = 0.035) and those who received T + GC (OR = 3.119, 95% CI: 1.576-6.173, p = 0.001) were more likely to develop thrombocytopenia. Patients aged over 70 years (OR = 3.213, 95% CI: 1.254-8.237, p = 0.015) were more likely to develop anemia, and patients with renal insufficiency (OR = 2.105, 95% CI: 1.035-4.280, p = 0.040) were more likely to develop leukopenia. Eventually, 99 (51.6%) patients with UC successfully completed all the treatment cycles. CONCLUSIONS: This study demonstrates that the addition of tislelizumab to GC chemotherapy led to a considerable increase in the occurrence of thrombocytopenia, whereas no significant changes were observed regarding anemia or leukopenia. It is crucial to fully inform patients at increased risk for myelosuppression of potential risks and closely monitor changes in their blood routines.


Asunto(s)
Anemia , Carcinoma de Células Transicionales , Leucopenia , Trombocitopenia , Neoplasias de la Vejiga Urinaria , Humanos , Anciano , Anciano de 80 o más Años , Cisplatino/uso terapéutico , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Carcinoma de Células Transicionales/patología , Gemcitabina , Puntaje de Propensión , Desoxicitidina/uso terapéutico , Trombocitopenia/inducido químicamente , Trombocitopenia/epidemiología , Leucopenia/inducido químicamente , Anemia/inducido químicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
20.
ArXiv ; 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-38076520

RESUMEN

Often linear regression is used to perform mediation analysis. However, in many instances, the underlying relationships may not be linear, as in the case of placentalfetal hormones and fetal development. Although, the exact functional form of the relationship may be unknown, one may hypothesize the general shape of the relationship. For these reasons, we develop a novel shape-restricted inference-based methodology for conducting mediation analysis. This work is motivated by an application in fetal endocrinology where researchers are interested in understanding the effects of pesticide application on birth weight, with human chorionic gonadotropin (hCG) as the mediator. We assume a practically plausible set of nonlinear effects of hCG on the birth weight and a linear relationship between pesticide exposure and hCG, with both exposure-outcome and exposure-mediator models being linear in the confounding factors. Using the proposed methodology on a population-level prenatal screening program data, with hCG as the mediator, we discovered that, while the natural direct effects suggest a positive association between pesticide application and birth weight, the natural indirect effects were negative.

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