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1.
Nat Mater ; 22(4): 489-494, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36959503

RESUMEN

Pressure-induced magnetic phase transitions are attracting interest as a means to detect superconducting behaviour at high pressures in diamond anvil cells, but determining the local magnetic properties of samples is a challenge due to the small volumes of sample chambers. Optically detected magnetic resonance of nitrogen vacancy centres in diamond has recently been used for the in situ detection of pressure-induced phase transitions. However, owing to their four orientation axes and temperature-dependent zero-field splitting, interpreting these optically detected magnetic resonance spectra remains challenging. Here we study the optical and spin properties of implanted silicon vacancy defects in 4H-silicon carbide that exhibit single-axis and temperature-independent zero-field splitting. Using this technique, we observe the magnetic phase transition of Nd2Fe14B at about 7 GPa and map the critical temperature-pressure phase diagram of the superconductor YBa2Cu3O6.6. These results highlight the potential of silicon vacancy-based quantum sensors for in situ magnetic detection at high pressures.

2.
Ann Plast Surg ; 93(3): 327-330, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38775257

RESUMEN

BACKGROUND: The closure of scalp wounds presents with reconstructive challenges due to the poor tissue elasticity. It is not uncommon to require skin grafts for definitive closure, even when large flaps are employed. Herein, we present a novel method for the direct closure of small- to medium-sized wounds defects. It is a modified bilateral rhomboid flap, which enables tension-free closure in many areas of scalp. METHODS: All patients treated with this technique between January 2018 and January 2023 were reviewed. Demographics, complications, and outcomes were reviewed. RESULTS: One hundred forty patients have been operated with this technique. All have been cases of skin tumors. The full flap survival was 97.14%, and they did not present any major local complications, avoiding in all cases the use of skin autografts. Four patients (2.86%) had partial necrosis in the edges of the flap, all managed with topical wound care with good healing and no need of secondary procedures. CONCLUSIONS: This flap is safe and easy to perform when there is skin laxity in the scalp. It can save many skin grafts, simplifying the closure of this area, which can be a first-choice technique on scalp reconstruction.


Asunto(s)
Procedimientos de Cirugía Plástica , Cuero Cabelludo , Neoplasias Cutáneas , Colgajos Quirúrgicos , Humanos , Cuero Cabelludo/cirugía , Masculino , Femenino , Colgajos Quirúrgicos/trasplante , Procedimientos de Cirugía Plástica/métodos , Neoplasias Cutáneas/cirugía , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Adulto , Trasplante de Piel/métodos , Anciano de 80 o más Años , Neoplasias de Cabeza y Cuello/cirugía , Resultado del Tratamiento
3.
Microsurgery ; 44(5): e31189, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38798132

RESUMEN

BACKGROUND: The pure skin perforator (PSP) flap is gaining popularity for its remarkable thinness. The subdermal dissection technique was recently introduced, allowing for a quicker elevation of a PSP flap. In this report, we present our two-year experience utilizing subdermal dissection for harvesting PSP flaps. METHODS: All patients who had undergone PSP flap reconstruction at our hospital from February 2021 to February 2023 were included. Demographic data, intraoperative variables, flap characteristics, and postoperative outcomes were collected. Surgical planning involved locating the perforator using ultrasound and harvesting the flap using the subdermal dissection technique. RESULTS: A total of 26 PSP flap reconstructions were conducted on 24 patients aged between 15 and 86 years. The flaps were based on perforators issuing from the superficial circumflex iliac artery in 24 cases, and from the descending branch of the lateral circumflex femoral artery in 2 cases. Flap sizes ranged from 3 × 1.5 cm to 19 × 6 cm, with a mean thickness of 3.48 mm. The average time for flap harvest was 131.92 min. Postoperatively, we observed four cases of partial necrosis, 1 total flap loss, and 2 instances of vascular thrombosis at the anastomosis site. The flaps exhibited good pliability without contracture, and no debulking procedures were required during the follow-up period (minimum 6 months, range 6-24; mean 9.4615). CONCLUSION: The subdermal dissection technique is a safe and efficient approach for elevating PSP flaps. Our initial experience with this technique has been encouraging, and it currently serves as our preferred reconstructive option for defects requiring thin reconstruction.


Asunto(s)
Quemaduras , Colgajo Perforante , Procedimientos de Cirugía Plástica , Humanos , Colgajo Perforante/irrigación sanguínea , Colgajo Perforante/trasplante , Adulto , Persona de Mediana Edad , Masculino , Femenino , Anciano , Adolescente , Procedimientos de Cirugía Plástica/métodos , Anciano de 80 o más Años , Adulto Joven , Quemaduras/cirugía , Estudios Retrospectivos , Disección/métodos , Resultado del Tratamiento , Trasplante de Piel/métodos
4.
Nano Lett ; 23(10): 4334-4343, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37155148

RESUMEN

Optically addressable spin defects in silicon carbide (SiC) have emerged as attractable platforms for various quantum technologies. However, the low photon count rate significantly limits their applications. We strongly enhanced the brightness by 7 times and spin-control strength by 14 times of single divacancy defects in 4H-SiC membranes using a surface plasmon generated by gold film coplanar waveguides. The mechanism of the plasmonic-enhanced effect is further studied by tuning the distance between single defects and the surface of the gold film. A three-energy-level model is used to determine the corresponding transition rates consistent with the enhanced brightness of single defects. Lifetime measurements also verified the coupling between defects and surface plasmons. Our scheme is low-cost, without complicated microfabrication and delicate structures, which is applicable for other spin defects in different materials. This work would promote developing spin-defect-based quantum applications in mature SiC materials.

5.
Rep Prog Phys ; 87(1)2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38029424

RESUMEN

This paper summarizes recent studies identifying key qubit systems in silicon carbide (SiC) for quantum sensing of magnetic, electric fields, and temperature at the nano and microscale. The properties of colour centres in SiC, that can be used for quantum sensing, are reviewed with a focus on paramagnetic colour centres and their spin Hamiltonians describing Zeeman splitting, Stark effect, and hyperfine interactions. These properties are then mapped onto various methods for their initialization, control, and read-out. We then summarised methods used for a spin and charge state control in various colour centres in SiC. These properties and methods are then described in the context of quantum sensing applications in magnetometry, thermometry, and electrometry. Current state-of-the art sensitivities are compiled and approaches to enhance the sensitivity are proposed. The large variety of methods for control and read-out, combined with the ability to scale this material in integrated photonics chips operating in harsh environments, places SiC at the forefront of future quantum sensing technology based on semiconductors.

6.
Cancer Control ; 30: 10732748231152322, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36662642

RESUMEN

BACKGROUND: An older age contributes to the development of bladder cancer. However, the relationship between advanced age at the diagnosis and prognosis of bladder cancer has been few reported. This study aimed to determine the effect of age on survival in bladder cancer with different subgroups. METHODS: 117,275 patients with bladder cancer, identified from the Surveillance, Epidemiology, and End Results database during 2004-2015 in America, were divided into 4 age groups (≤54, 55 to 64, 65 to 74, and ≥75 years). Multivariable Cox proportional-hazards model and competing risk model were conducted according to different age groups. Heat maps were plotted to show the impact of age on survival in subgroups classified by other clinicopathological variables. Moreover, restricted cubic spline was used to model the association between age and the risk of death. RESULTS: Patients aged ≥75 years had shorter overall survival in comparison with those aged ≤54 years (hazard ratio [HR] = 5.36, 95% confidence interval [CI] = 5.13-5.59). Compared with patients aged ≤54 years, patients older than 75 years experienced a decreased rate of bladder cancer-specific survival (subdistribution HR = 2.15, 95% CI = 2.04-2.25). Heat maps also showed that older ages were associated with worse overall cumulative mortality and bladder cancer-specific cumulative mortality. Similarly, restricted cubic spline verified the impact of age on survival of bladder cancer. CONCLUSIONS: Age at diagnosis of bladder cancer was found to be a significant predictor for the worse overall survival and bladder cancer-specific survival even in an era with more effective therapies. Exploring the reasons why older age contributes to poor outcomes for bladder cancer will be the focus of future research.


Asunto(s)
Neoplasias de la Vejiga Urinaria , Humanos , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/epidemiología , Neoplasias de la Vejiga Urinaria/patología , Cistectomía/métodos , Factores de Edad , Programa de VERF
7.
Neoplasma ; 70(6): 713-721, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37962863

RESUMEN

Metabolic rewiring of tumor cells leads to an enrichment of lactate in the tumor microenvironment (TME). This lactate-rich environment of solid tumors has been reported to support tumor-infiltrating regulatory T (Treg) cells. Therefore, agents that modify the lactate metabolism of Treg cells have therapeutic potential. Monocarboxylate transporter 1 (MCT1), which Treg cells predominantly express, plays an essential role in the metabolism of tumor-infiltrating Treg cells. In this study, we show that miR-124 directly targets MCT1 and reduces lactate uptake, eventually impairing the immune-suppressive capacity of Treg cells. Particularly, exosomal miR-124 derived from bone marrow mesenchymal stromal cells (BM-MSCs) slows tumor growth and increases response to PD-1 blockade therapy. These data indicate a potential treatment strategy for improving immune checkpoint blockade therapy using miR-124-carried BM-MSCs-derived exosomes.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , MicroARNs , Neoplasias Ováricas , Humanos , Femenino , Linfocitos T Reguladores , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Ováricas/terapia , Neoplasias Ováricas/metabolismo , Inmunoterapia , Células Madre Mesenquimatosas/metabolismo , Lactatos/metabolismo , Microambiente Tumoral
8.
Nano Lett ; 22(24): 9943-9950, 2022 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-36507869

RESUMEN

Spin defects in silicon carbide appear to be a promising tool for various quantum technologies, especially for quantum sensing. However, this technique has been used only at ambient pressure until now. Here, by combining this technique with diamond anvil cell, we systematically study the optical and spin properties of divacancy defects created at the surface of SiC at pressures up to 40 GPa. The zero-field-splitting of the divacancy spins increases linearly with pressure with a slope of 25.1 MHz/GPa, which is almost two-times larger than that of nitrogen-vacancy centers in diamond. The corresponding pressure sensing sensitivity is about 0.28 MPa/Hz-1/2. The coherent control of divacancy demonstrates that coherence time decreases as pressure increases. Based on these, the pressure-induced magnetic phase transition of Nd2Fe14B sample at high pressures was detected. These experiments pave the way to use divacancy in quantum technologies such as pressure sensing and magnetic detection at high pressures.

9.
J Transl Med ; 20(1): 52, 2022 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-35093110

RESUMEN

It is widely acknowledged that gastric cancer seriously affects the quality of life and survival of patients. The correlation between the microbiota and gastric cancer has attracted extensive attention in recent years, nonetheless the specific mechanism of its impact on gastric cancer remain largely unclear. Recent studies have shown that in addition to its role in the host's inflammatory and immune response, the microbiota can also affect the occurrence and development of gastric cancer by affecting the expression of miRNAs. This paper brings together all currently available data on miRNAs, microbiota and gastric cancer, and preliminarily describes the relationship among them.


Asunto(s)
MicroARNs , Microbiota , Neoplasias Gástricas , Interacciones Microbiota-Huesped , Humanos , MicroARNs/genética , Calidad de Vida , Neoplasias Gástricas/genética
10.
J Transl Med ; 20(1): 439, 2022 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-36180919

RESUMEN

BACKGROUND: Globally, gastric cancer is the third most common cancer and the third leading cause of cancer death. Proximal and distal gastric cancers have distinct clinical and biological behaviors. The microbial composition and metabolic differences in proximal and distal gastric cancers have not been fully studied and discussed. METHODS: In this study, the gastric microbiome of 13 proximal gastric cancer tissues, 16 distal gastric cancer tissues, and their matched non-tumor tissues were characterized using 16S rRNA amplicon sequencing. Additionally, 10 proximal gastric cancer tissues, 11 distal gastric cancer tissues, and their matched non-tumor tissues were assessed by untargeted metabolomics. RESULTS: There was no significant difference in microbial diversity and richness between the proximal and distal gastric cancer tissues. At the genus level, the abundance of Rikenellaceae_RC9_gut_group, Porphyromonas, Catonella, Proteus, Oribacterium, and Moraxella were significantly increased in Proximal T, whereas that of Methylobacterium_Methylorubrum was significantly increased in Distal T. The untargeted metabolomics analysis revealed 30 discriminative metabolites between Distal T and Distal N. In contrast, there were only 4 discriminative metabolites between Proximal T and Proximal N. In distal gastric cancer, different metabolites were scattered through multiple pathway, including the sphingolipid signaling pathway, arginine biosynthesis, protein digestion and absorption, alanine, aspartate and, glutamate metabolism, etc.In proximal gastric cancer, differential microbial metabolites were mainly related to hormone metabolism. CONCLUSION: Methylobacterium-Methylorubrum was significantly increased in Distal T, positively correlated with cancer-promoting metabolites, and negatively correlated with cancer-inhibiting metabolites. Rikenellaceae_RC_gut_group was significantly increased in Proximal T and positively correlated with cancer-promoting metabolites. Further studies regarding the functions of the above-mentioned microorganisms and metabolites were warranted as the results may reveal the different mechanisms underlying the occurrence and development of proximal and distal gastric cancers and provide a basis for future treatments. IMPORTANCE: First, the differences in microbial composition and metabolites between the proximal and distal gastric cancers were described; then, the correlation between microbiota and metabolites was preliminarily discussed. These microbes and metabolites deserve further investigations as they may reveal the different mechanisms involved in the occurrence and development of proximal and distal gastric cancers and provide a basis for future treatments.


Asunto(s)
Microbiota , Neoplasias Gástricas , Alanina , Arginina , Ácido Aspártico , Heces/microbiología , Glutamatos , Hormonas , Humanos , Metabolómica/métodos , ARN Ribosómico 16S/genética , Esfingolípidos
11.
BMC Gastroenterol ; 22(1): 114, 2022 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-35264117

RESUMEN

BACKGROUND: Whether primary tumor location (PTL) is predictive of survival benefits following primary tumor resection plus metastasectomy (PMTR) and primary tumor resection (PTR) alone in stage IV colorectal cancer patients is not known. We sought to address this issue by employing instrumental variable analysis to evaluate the efficacy of PMTR and PTR with stratification for primary tumor location in stage IV colorectal cancer patients. PATIENTS AND METHODS: Stage IV colorectal cancer patients diagnosed between January 1, 2005 and December 31, 2015 were identified from the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute. To account for both measured and unmeasured confounders, the efficacy of PMTR and PTR in the left- and right-sided subgroups was evaluated using instrumental variable analysis, with the health service area as the instrument variable. Overall survival (OS) was the primary outcome of interest. RESULTS: A total of 50,333 eligible patients were analyzed (left-sided, n = 29,402 and right-sided, n = 20,931). OS was significantly better with PMTR than with other treatments (PTR, metastasectomy only, or no surgery) in patients with left-sided tumors (hazard ratio [HR] = 0.37 [95% CI 0.24-0.58], P < 0.001), but not in patients with right-sided tumors (HR = 0.98 [95% CI 0.65-1.47], P = 0.910; interaction test P < 0.001). OS was comparable in patients treated with PTR and those treated with no surgery in both the left-sided (HR = 1.11 [95% CI 0.68-1.81], P = 0.690) and right-sided (HR = 0.85 [95% CI 0.50-1.43], P = 0.530; interaction test P = 0.466) subgroups. CONCLUSIONS: PMTR appears to only benefit patients with left-sided stage IV colorectal cancer but not those with right-sided tumors. PTR does not improve OS, regardless of primary tumor location. When selecting patients for PMTR, primary tumor location should be considered. Overuse of PTR should be avoided.


Asunto(s)
Neoplasias Colorrectales , Metastasectomía , Neoplasias Colorrectales/patología , Humanos , Pronóstico , Modelos de Riesgos Proporcionales , Programa de VERF
12.
Neoplasma ; 69(5): 1129-1137, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36131607

RESUMEN

Tumor cells show deregulated metabolism leading to an enrichment of lactate in the tumor microenvironment (TME). This lactate-rich environment has been reported to impair effector T cells. However, T-regulatory cells (Tregs) show metabolic advantages in lactate-rich TME that maintain a strong suppression of effector T cells, which leads to tumor immune evasion. Therefore, the glycolytic process of tumors could represent a therapeutic target, and agents that modify the energy metabolism of tumor cells have therapeutic potential. Resveratrol is a naturally occurring polyphenol that has been confirmed to suppress tumor cells' glycolytic metabolism. In this study, we show that resveratrol induces metabolic reprogramming in ovarian cancer cells. Resveratrol increases oxidative and decreases glycolysis, in association with decreased lactate production both in vitro and in vivo. Lactate reduction in TME weakens the suppressive function of Tregs, and subsequently restores anti-tumor immunity. Significantly, combined resveratrol and PD-1 blockade promote anti-tumor efficacy. These data suggest that resveratrol's anti-tumor actions in ovarian cancer could be explained, in part, through modification of the anti-tumor immunity, and indicate a novel treatment strategy for improving immune checkpoint blockade therapy using resveratrol.


Asunto(s)
Neoplasias , Neoplasias Ováricas , Carcinoma Epitelial de Ovario , Femenino , Humanos , Inhibidores de Puntos de Control Inmunológico , Ácido Láctico , Neoplasias/tratamiento farmacológico , Neoplasias Ováricas/patología , Polifenoles , Receptor de Muerte Celular Programada 1 , Resveratrol/farmacología , Microambiente Tumoral
13.
Health Care Manag Sci ; 25(2): 208-221, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34633589

RESUMEN

In this paper, we consider a stochastic optimization model for a surgical scheduling problem with a single operating room. The goal is to determine the optimal start times of multiple elective surgeries within a single day. The term "optimal" is defined as the largest surgically related utility value while achieving a given threshold defined by the performance variation of a reference solution. The optimization problem is analytically intractable because it involves quantities such as expectation and variance formulations. This implies that traditional mathematical programming techniques cannot be directly applied. We propose a decision support algorithm, which is a fully sequential procedure using variance screening in the first phase, and then employing multiple attribute utility theory to select the best solution in the second phase. The numerical experiments show that the proposed algorithm can find a promising solution in a reasonable amount of time.


Asunto(s)
Modelos Teóricos , Admisión y Programación de Personal , Algoritmos , Humanos , Quirófanos , Factores de Tiempo
14.
Molecules ; 27(7)2022 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-35408540

RESUMEN

Lyciumruthenicum Murray (L. ruthenicum) has been used both as traditional Chinese medicine and food. Recent studies indicated that anthocyanins are the most abundant bioactive compounds in the L. ruthenicum fruits. The purpose of this study was to investigate the preventive effects and the mechanism of the anthocycanins from the fruit of L. ruthenicum (ACN) in high-fat diet-induced obese mice. In total, 24 male C57BL/6J mice were divided into three groups: control group (fed a normal diet), high-fat diet group (fed a high-fat diet, HFD), and HFD +ACN group (fed a high-fat diet and drinking distilled water that contained 0.8% crude extract of ACN). The results showed that ACN could significantly reduce the body weight, inhibit lipid accumulation in liver and white adipose tissue, and lower the serum total cholesterol and low-density lipoprotein cholesterol levels compared to that of mice fed a high-fat diet. 16S rRNA gene sequencing of bacterial DNA demonstrated that ACN prevent obesity by enhancing the diversity of cecal bacterial communities, lowering the Firmicutes-to-Bacteroidota ratio, increasing the genera Akkermansia, and decreasing the genera Faecalibaculum. We also studied the inhibitory effect of ACN on pancreatic lipase. The results showed that ACN has a high affinity for pancreatic lipase and inhibits the activity of pancreatic lipase, with IC50 values of 1.80 (main compound anthocyanin) and 3.03 mg/mL (crude extract), in a competitive way. Furthermore, fluorescence spectroscopy studies showed that ACN can quench the intrinsic fluorescence of pancreatic lipase via a static mechanism. Taken together, these findings suggest that the anthocyanins from L. ruthenicum fruits could have preventive effects in high-fat-diet induced obese mice by regulating the intestinal microbiota and inhibiting the pancreatic lipase activity.


Asunto(s)
Dieta Alta en Grasa , Microbioma Gastrointestinal , Animales , Antocianinas/química , Antocianinas/farmacología , Colesterol/farmacología , Dieta Alta en Grasa/efectos adversos , Lipasa , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Extractos Vegetales/farmacología , ARN Ribosómico 16S
15.
BMC Med ; 19(1): 26, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33526018

RESUMEN

BACKGROUND: A critical and challenging process in immunotherapy is to identify cancer patients who could benefit from immune checkpoint inhibitors (ICIs). Exploration of predictive biomarkers could help to maximize the clinical benefits. Eph receptors have been shown to play essential roles in tumor immunity. However, the association between EPH gene mutation and ICI response is lacking. METHODS: Clinical data and whole-exome sequencing (WES) data from published studies were collected and consolidated as a discovery cohort to analyze the association between EPH gene mutation and efficacy of ICI therapy. Another independent cohort from Memorial Sloan Kettering Cancer Center (MSKCC) was adopted to validate our findings. The Cancer Genome Atlas (TCGA) cohort was used to perform anti-tumor immunity and pathway enrichment analysis. RESULTS: Among fourteen EPH genes, EPHA7-mutant (EPHA7-MUT) was enriched in patients responding to ICI therapy (FDR adjusted P < 0.05). In the discovery cohort (n = 386), significant differences were detected between EPHA7-MUT and EPHA7-wildtype (EPHA7-WT) patients regarding objective response rate (ORR, 52.6% vs 29.1%, FDR adjusted P = 0.0357) and durable clinical benefit (DCB, 70.3% vs 42.7%, FDR adjusted P = 0.0200). In the validation cohort (n = 1144), significant overall survival advantage was observed in EPHA7-MUT patients (HR = 0.62 [95% confidence interval, 0.39 to 0.97], multivariable adjusted P = 0.0367), which was independent of tumor mutational burden (TMB) and copy number alteration (CNA). Notably, EPHA7-MUT patients without ICI therapy had significantly worse overall survival in TCGA cohort (HR = 1.33 [95% confidence interval, 1.06 to 1.67], multivariable adjusted P = 0.0139). Further gene set enrichment analysis revealed enhanced anti-tumor immunity in EPHA7-MUT tumor. CONCLUSIONS: EPHA7-MUT successfully predicted better clinical outcomes in ICI-treated patients across multiple cancer types, indicating that EPHA7-MUT could serve as a potential predictive biomarker for immune checkpoint inhibitors.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico/metabolismo , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Receptor EphA7/metabolismo , Biomarcadores de Tumor/genética , Estudios de Cohortes , Variaciones en el Número de Copia de ADN , Humanos , Inmunoterapia , Masculino , Persona de Mediana Edad , Mutación
16.
Org Biomol Chem ; 19(40): 8696-8700, 2021 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-34581380

RESUMEN

A mild and facile approach to construct various perfluoroketones via photo-catalyzed difluoroalkylation of difluoroenoxysilanes is developed. The reaction includes a strategy of combination of two fluorine-containing functional groups, which confers the reaction with characteristics like high efficiency, mild conditions, and broad scope. A variety of fluoroalkyl halides including perfluoroalkyl iodides, bromo difluoro esters and amides can be employed as radical precursors. Control experiments indicate that a single-electron transfer pathway may be involved in the reaction.

17.
Phys Chem Chem Phys ; 23(32): 17323-17328, 2021 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-34346442

RESUMEN

High-index faceted Pt nanoparticles with excellent electrocatalytic performances are promising to efficiently accelerate the oxygen reduction reactions in fuel cells. By adopting the hybrid grand canonical Monte Carlo reactive molecular dynamics (GCMC/RMD) simulations, we examined the oxygen adsorption on three 24-facet nanoparticles respectively enclosed by {310}, {311}, and {331} high-index facets. The site-dependent adsorption energies on each open-structure surface are calculated. Meanwhile, the adsorption ratios under various pressures and temperatures are presented. It is revealed that the adsorption capacity of these high-index faceted nanoparticles is considerably higher than that of the ones terminated by low-index facets. Moreover, oxygen adsorption exerts a significant impact on their thermodynamic behaviors.

18.
Biosci Biotechnol Biochem ; 85(2): 233-241, 2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33604631

RESUMEN

Eucommia ulmoides is an economic tree that can biosynthesize secondary metabolites with pharmacological functions. Genetic basis of biosynthesis of these compounds is almost unknown. Therefore, genomic-wide association study was performed to exploit the genetic loci maybe involved in biosynthetic pathways of 5 leaf inclusions (aucubin, chlorogenic acid, gutta-percha, polyphenols, total flavonoids). It was shown that contents of the 5 leaf metabolites have a wide variation following normal distribution. A total of 2 013 102 single nucleotide polymorphism (SNP) markers were identified in a population containing 62 individual clones. Through genome-wide association study analysis, many SNP loci were identified perhaps associated with phenotypes of the leaf inclusions. Higher transcriptional levels of the candidate genes denoted by significant SNPs in leaves suggested they may be involved in biosynthesis of the leaf inclusions. These genetic loci provide with invaluable information for further studies on the gene functions in biosynthesis of the leaf inclusions and selective breeding of the plus trees.


Asunto(s)
Eucommiaceae/genética , Genes de Plantas/genética , Estudio de Asociación del Genoma Completo , Hojas de la Planta/metabolismo , Eucommiaceae/metabolismo , Perfilación de la Expresión Génica , Fenotipo , Polimorfismo de Nucleótido Simple
19.
BMC Womens Health ; 21(1): 274, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-34320962

RESUMEN

BACKGROUND: Pelvic inflammatory disease (PID) is an important health issue for women. Infection and inflammation play an important role in carcinogenesis and PID has been reported to be associated with ovarian cancer in some small scale studies. AIM: We sought to determine whether PID is associated with an elevated risk of ovarian cancer in Asian women. METHODS: Using data from Taiwan's National Health Insurance Research Database (NHIRD), our retrospective cohort study included women diagnosed with PID (cases) between the years of 2000 till 2012. Each case was matched with two women without PID (controls) by age and the year of first entry into the database. Both study cohorts were followed-up until the first event of ovarian cancer, withdrawal from the NHI program, death, or the end of the study period (December 31, 2012). Cox proportional hazards regression models were used to estimate crude and adjusted hazard ratios (HRs and aHRs) with their corresponding 95% confidence intervals (95% CIs) for the association of PID and ovarian cancer risk, with and without adjusting for potential confounders. RESULTS: During an approximate 10 years of follow-up, cases were significantly more likely than controls to develop ovarian cancer (incidence rates of 0.27 and 0.16 per 1,000 person-years, respectively; P < 0.001). Women with a history of PID had a 1.49-fold elevated risk for ovarian cancer (aHR, 1.49; 95% CI, 1.21-1.84; P < 0.001). CONCLUSION: Our study evidence supports the contention that PID increases the risk of developing ovarian cancer among Taiwanese women. Gynecologists should undertake careful assessments and closely follow patients with PID, who are at long-term risk of developing ovarian cancer. Our findings need further verification in other international cohorts.


Asunto(s)
Neoplasias Ováricas , Enfermedad Inflamatoria Pélvica , Estudios de Cohortes , Femenino , Humanos , Incidencia , Neoplasias Ováricas/epidemiología , Enfermedad Inflamatoria Pélvica/complicaciones , Enfermedad Inflamatoria Pélvica/epidemiología , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Taiwán/epidemiología
20.
BMC Pregnancy Childbirth ; 20(1): 217, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32295527

RESUMEN

BACKGROUND: The incidence of female stroke has increased gradually and has begun occurring at a younger age in recent years. Given that women live longer than men, stroke would cause more negative and longer-term impacts on the rest of the lives of women. There are few related studies on Asian women. We aimed to evaluate stroke risk in Asian women following hypertensive pregnancy disorders. METHODS: Using the Taiwan National Health Insurance database, we designed a retrospective study that included pregnant women between 2000 and 2013. We selected an age-matched control group of women without hypertensive pregnancy disorders at a 1:3 ratio. The endpoint was any episode of stroke; otherwise, the patients were tracked until December 31, 2013. After the index date until the end of 2013, Cox proportional hazards analysis was used to compare the risk of incident stroke. The risk factors for stroke were determined using Cox proportional regression to calculate the hazard ratio (HR) compared with the control group. RESULTS: During the follow-up period, the Kaplan-Meier analysis indicated that patients with hypertensive pregnancy disorders had a significantly higher risk of developing stroke than did patients without hypertensive pregnancy disorders (log-rank test P < 0.001). Multivariate Cox regression analysis demonstrated that the case group had a 2.134-fold increased risk of stroke (HR = 2.134; 95% CI = 1.817-2.505; P < 0.001). CONCLUSION: Our study provided evidence of an increased risk of stroke in patients with hypertensive pregnancy disorders. Compared with those without such disorders, the patients who had experienced the disorders had a 2.134-fold (P < 0.001) higher risk of developing stroke in the future.


Asunto(s)
Hipertensión Inducida en el Embarazo/epidemiología , Accidente Cerebrovascular/epidemiología , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Femenino , Predicción , Humanos , Incidencia , Estimación de Kaplan-Meier , Embarazo , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Taiwán/epidemiología , Adulto Joven
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