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1.
Small ; 20(25): e2308421, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38221693

RESUMEN

High-entropy alloys nanoparticles (HEAs NPs) have gained considerable attention due to their extensive compositional tunability and intriguing catalytic properties. However, the synthesis of highly dispersed ultrasmall HEAs NPs remains a formidable challenge due to their inherent thermodynamic instability. In this study, highly dispersed ultrasmall (ca. 2 nm) PtCuGaFeCo HEAs NPs are synthesized using a one-pot solution-based method at 160 °C and atmospheric pressure. The PtCuGaFeCo NPs exhibit good catalytic activity for the oxygen reduction reaction (ORR). The half-wave potential relative to the reversible hydrogen electrode (RHE) reaches 0.88 V, and the mass activity and specific activity are approximately six times and four times higher than that of the commercial Pt/C catalyst. Based on X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) analyses, the surface strain and optimized coordination environments of PtCuGaFeCo have led to high ORR activities in acidic media. Moreover, the ultrasmall size also plays an important role in enhancing catalytic performance. The work presents a facile and viable synthesis strategy for preparing the ultrasmall HEAs NPs, offering great potential in energy and electrocatalysis applications through entropy engineering.

2.
Crit Care Med ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38832833

RESUMEN

OBJECTIVES: This study aimed to systematically assess the methodological quality and key recommendations of the guidelines for the diagnosis and treatment of liver failure (LF), furnishing constructive insights for guideline developers and equipping clinicians with evidence-based information to facilitate informed decision-making. DATA SOURCES: Electronic databases and manual searches from January 2011 to August 2023. STUDY SELECTION: Two reviewers independently screened titles and abstracts, then full texts for eligibility. Fourteen guidelines were included. DATA EXTRACTION AND SYNTHESIS: Two reviewers extracted data and checked by two others. Methodological quality of the guidelines was appraised using the Appraisal of Guidelines for Research and Evaluation II tool. Of the 14 guidelines, only the guidelines established by the Society of Critical Care Medicine and the American College of Gastroenterology (2023) achieved an aggregate quality score exceeding 60%, thereby meriting clinical recommendations. It emerged that there remains ample room for enhancement in the quality of the guidelines, particularly within the domains of stakeholder engagement, rigor, and applicability. Furthermore, an in-depth scrutiny of common recommendations and supporting evidence drawn from the 10 adult LF guidelines unveiled several key issues: controversy exists in the recommendation, the absence of supporting evidence and confusing use of evidence for recommendations, and a preference in evidence selection. CONCLUSIONS: There are high differences in methodological quality and recommendations among LF guidelines. Improving these existing problems and controversies will benefit existing clinical practice and will be an effective way for developers to upgrade the guidelines.

3.
Scand J Gastroenterol ; 59(1): 62-69, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37649307

RESUMEN

BACKGROUND AND AIMS: There is no golden standard for the diagnosis of autoimmune hepatitis which still dependent on liver biopsy currently. So, we developed a noninvasive prediction model to help optimize the diagnosis of autoimmune hepatitis. METHODS: From January 2017 to December 2019, 1739 patients who had undergone liver biopsy were seen in the second hospital of Nanjing, of which 128 were here for consultation. Clinical, laboratory, and histologic data were obtained retrospectively. Multivariable logistic regression analysis was employed to create a nomogram model that predicting the risk of autoimmune hepatitis. Internal and external validation was both performed to evaluate the model. RESULTS: A total of 1288 patients with liver biopsy were enrolled (1184 from the second hospital of Nanjing, the remaining 104 from other centers). After the univariate and multivariate logistic regression analysis, nine variables including ALT, IgG, ALP/AST, ALB, ANA, AMA, HBsAg, age, and gender were selected to establish the noninvasive prediction model. The nomogram model exhibits good prediction in diagnosing autoimmune hepatitis with AUROC of 0.967 (95% CI: 0.776-0.891) in internal validation and 0.835 (95% CI: 0.752-0.919) in external validation. CONCLUSIONS: ALT, IgG, ALP/AST, ALB, ANA, AMA, HBsAg, age, and gender are predictive factors for the diagnosis of autoimmune hepatitis in patients with unexplained liver diseases. The predictive nomogram model built by the nine predictors achieved good prediction for diagnosing autoimmune hepatitis.


Asunto(s)
Hepatitis Autoinmune , Humanos , Hepatitis Autoinmune/complicaciones , Hepatitis Autoinmune/diagnóstico , Estudios Retrospectivos , Antígenos de Superficie de la Hepatitis B , Nomogramas , Inmunoglobulina G
4.
World J Surg Oncol ; 22(1): 21, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38243254

RESUMEN

BACKGROUND: After radical surgery, early detection of recurrence and metastasis is a crucial factor in enhancing the prognosis and survival of patients with gastric cancer (GC). Therefore, assessing the risk of recurrence in gastric cancer patients and determining the timing for postoperative recurrence is crucial. METHODS: The clinicopathological data of 521 patients with recurrent gastric cancer, who underwent radical gastrectomy at Zhejiang Cancer Hospital between January 2010 and January 2017, were retrospectively analyzed. These patients were randomly divided into two groups: a training group (n = 365) and a validation group (n = 156). In the training set, patients were further categorized into early recurrence (n = 263) and late recurrence (n = 102) groups based on a 2-year boundary. Comparative analyses of clinicopathological features and prognoses were conducted between these two groups. Subsequently, a nomogram for predicting early recurrence was developed and validated. RESULTS: In this study, the developed nomogram incorporated age, serous infiltration, lymph node metastasis, recurrence mode, and the tumour marker CA19-9. In the training cohort, the area under the curve (AUC value) was 0.739 (95% CI, 0.682-0.798), with a corresponding C-index of 0.739. This nomogram was subsequently validated in an independent validation cohort, yielding an AUC of 0.743 (95% CI, 0.652-0.833) and a C-index of 0.743. Furthermore, independent risk factors for prognosis were identified, including age, absence of postoperative chemotherapy, early recurrence, lymph node metastasis, abdominal metastasis, and vascular cancer embolus. CONCLUSION: Independent risk factors for gastric cancer recurrence following radical surgery were utilized to construct a nomogram for predicting early relapse. This nomogram effectively assesses the risk of recurrence, aids in treatment decision-making and follow-up planning in clinical settings, and demonstrated strong performance in the validation cohort.


Asunto(s)
Nomogramas , Neoplasias Gástricas , Humanos , Estudios Retrospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirugía , Metástasis Linfática , Gastrectomía/efectos adversos
5.
J Dairy Sci ; 107(7): 4333-4343, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38101743

RESUMEN

The objective of this study was to examine the aroma profiles of 12 Gouda cheeses sold in China and to determine which aromas were preferred by young Chinese consumers (n = 110). The consumers selected 11 descriptors of the aromas of the Gouda cheeses in a check-all-that-apply questionnaire. These 11 descriptors were used by a panel of experts for sensory analysis to perform a quantitative descriptive analysis of the cheeses. A principal component analysis of the data from the quantitative descriptive analysis revealed that the characteristic aromas of young Gouda cheeses, medium-aged Gouda cheeses, and aged Gouda cheeses were "milky" and "whey"; "creamy" and "sour"; and "rancid" and "nutty," respectively. The results of a penalty analysis combined with the check-all-that-apply results and the preference scores showed that the 3 groups of young Chinese consumers (those who often ate cheese, occasionally ate cheese, and never ate cheese) preferred the Gouda cheeses with "milky" or "creamy" aromas and did not enjoy those with "sour" or "rancid" aromas. Occasional cheese eaters comprised the majority of the young Chinese consumers, and they were more tolerant of the Gouda cheeses with "whey" and "sulfury" aromas than those who often or never ate cheese. In addition, we identified a positive correlation between the consumers' preferences for the aromas of the Gouda cheeses and their willingness to pay for them. Overall, the results of this study should help promote the development of Gouda cheeses and associated products that meet the preferences of young Chinese consumers.


Asunto(s)
Queso , Comportamiento del Consumidor , Odorantes , Gusto , Humanos , China , Animales , Encuestas y Cuestionarios , Femenino , Pueblos del Este de Asia
6.
Angew Chem Int Ed Engl ; 63(3): e202315943, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38057544

RESUMEN

The crystal growth and orientation of two-dimensional (2D) perovskite films significantly impact solar cell performance. Here, we incorporated robust quadrupole-quadrupole interactions to govern the crystal growth of 2D Ruddlesden-Popper (RP) perovskites. This was achieved through the development of two unique semiconductor spacers, namely PTMA and 5FPTMA, with different dipole moments. The ((5FPTMA)0.1 (PTMA)0.9 )2 MAn-1 Pbn I3n+1 (nominal n=5, 5F/PTMA-Pb) film shows a preferred vertical orientation, reduced grain boundaries, and released residual strain compared to (PTMA)2 MAn-1 Pbn I3n+1 (nominal n=5, PTMA-Pb), resulting in a decreased exciton binding energy and reduced electron-phonon coupling coefficients. In contrast to PTMA-Pb device with an efficiency of 15.66 %, the 5F/PTMA-Pb device achieved a champion efficiency of 18.56 %, making it among the best efficiency for 2D RP perovskite solar cells employing an MA-based semiconductor spacer. This work offers significant insights into comprehending the crystal growth process of 2D RP perovskite films through the utilization of quadrupole-quadrupole interactions between semiconductor spacers.

7.
Angew Chem Int Ed Engl ; 63(17): e202402373, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38441483

RESUMEN

Electrochemiluminescence (ECL) efficiency is determined by charge transfer between coreactants and emitters in coreactant systems, which are usually limited by their slow intermolecular charge transfer. In this study, a covalent organic framework (COF) with aldehyde residue was synthesized, and then coreactants were covalently integrated into the skeleton through the postsynthetic modification strategy, resulting in a crystalline coreactant-embedded COF nanoemitter (C-COF). Compared to the pristine COF with an equivalent external coreactant, C-COF exhibited an extraordinary 1008-fold enhancement of ECL intensity due to the rapid intrareticular charge transfer. Significantly, with the pH increase, C-COF shows protonation-induced ECL enhancement for the first ECL peaked at +1.1 V and an opposite trend for the second ECL at +1.4 V, which were attributed to the antedating oxidation of coreactant in framework and COF self-oxidation, respectively. The resulting bimodal oxidation ECL mechanism was rationalized by spectral characterization and density functional theory calculations. The postsynthetic coreactant-embedded nanoemitters present innovative and universal avenues for advancing ECL systems.

8.
Angew Chem Int Ed Engl ; : e202405313, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738593

RESUMEN

Three-dimensional covalent organic frameworks (3D COFs), recognized for their tailorable structures and accessible active sites, offer a promising platform for developing advanced photocatalysts. However, the difficulty in the synthesis and functionalization of 3D COFs hinders their further development. In this study, we present a series of 3D-bcu-COFs with 8 connected porphyrin units linked by linear linkers through imine bonds as a versatile platform for photocatalyst design. The photoresponse of 3D-bcu-COFs was initially modulated by functionalizing linear linkers with benzo-thiadiazole or benzo-selenadiazole groups. Furthermore, taking advantage of the well-exposed porphyrin and imine sites in 3D-bcu-COFs, their photocatalytic activity was optimized by stepwise protonation of imine bonds and porphyrin centers. The dual protonated COF with benzo-selenadiazole groups exhibited enhanced charge separation, leading to an increased photocatalytic H2O2 production under visible light. This enhancement demonstrates the combined benefits of linker functionalization and stepwise protonation on photocatalytic efficiency.

9.
Gut ; 72(11): 2051-2067, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37460165

RESUMEN

OBJECTIVE: Metabolic biomarkers are expected to decode the phenotype of gastric cancer (GC) and lead to high-performance blood tests towards GC diagnosis and prognosis. We attempted to develop diagnostic and prognostic models for GC based on plasma metabolic information. DESIGN: We conducted a large-scale, multicentre study comprising 1944 participants from 7 centres in retrospective cohort and 264 participants in prospective cohort. Discovery and verification phases of diagnostic and prognostic models were conducted in retrospective cohort through machine learning and Cox regression of plasma metabolic fingerprints (PMFs) obtained by nanoparticle-enhanced laser desorption/ionisation-mass spectrometry (NPELDI-MS). Furthermore, the developed diagnostic model was validated in prospective cohort by both NPELDI-MS and ultra-performance liquid chromatography-MS (UPLC-MS). RESULTS: We demonstrated the high throughput, desirable reproducibility and limited centre-specific effects of PMFs obtained through NPELDI-MS. In retrospective cohort, we achieved diagnostic performance with areas under curves (AUCs) of 0.862-0.988 in the discovery (n=1157 from 5 centres) and independent external verification dataset (n=787 from another 2 centres), through 5 different machine learning of PMFs, including neural network, ridge regression, lasso regression, support vector machine and random forest. Further, a metabolic panel consisting of 21 metabolites was constructed and identified for GC diagnosis with AUCs of 0.921-0.971 and 0.907-0.940 in the discovery and verification dataset, respectively. In the prospective study (n=264 from lead centre), both NPELDI-MS and UPLC-MS were applied to detect and validate the metabolic panel, and the diagnostic AUCs were 0.855-0.918 and 0.856-0.916, respectively. Moreover, we constructed a prognosis scoring system for GC in retrospective cohort, which can effectively predict the survival of GC patients. CONCLUSION: We developed and validated diagnostic and prognostic models for GC, which also contribute to advanced metabolic analysis towards diseases, including but not limited to GC.

10.
Stroke ; 54(8): 1974-1984, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37350270

RESUMEN

BACKGROUND: Repeat stereotactic radiosurgery (SRS) for persistent cerebral arteriovenous malformation (AVM) has generally favorable patient outcomes. However, reporting studies are limited by small patient numbers and single-institution biases. The purpose of this study was to provide the combined experience of multiple centers, in an effort to fully define the role of repeat SRS for patients with arteriovenous malformation. METHODS: This multicenter, retrospective cohort study included patients treated with repeat, single-fraction SRS between 1987 and 2022. Follow-up began at repeat SRS. The primary outcome was a favorable patient outcome, defined as a composite of nidus obliteration in the absence of hemorrhage or radiation-induced neurological deterioration. Secondary outcomes were obliteration, hemorrhage risk, and symptomatic radiation-induced changes. Competing risk analysis was performed to compute yearly rates and identify predictors for each outcome. RESULTS: The cohort comprised 505 patients (254 [50.3%] males; median [interquartile range] age, 34 [15] years) from 14 centers. The median clinical and magnetic resonance imaging follow-up was 52 (interquartile range, 61) and 47 (interquartile range, 52) months, respectively. At last follow-up, favorable outcome was achieved by 268 (53.1%) patients (5-year probability, 50% [95% CI, 45%-55%]) and obliteration by 300 (59.4%) patients (5-year probability, 56% [95% CI, 51%-61%]). Twenty-eight patients (5.6%) experienced post-SRS hemorrhage with an annual incidence rate of 1.38 per 100 patient-years. Symptomatic radiation-induced changes were evident in 28 (5.6%) patients, with most occurring in the first 3 years. Larger nidus volumes (between 2 and 4 cm3, subdistribution hazard, 0.61 [95% CI, 0.44-0.86]; P=0.005; >4 cm3, subdistribution hazard, 0.47 [95% CI, 0.32-0.7]; P<0.001) and brainstem/basal ganglia involvement (subdistribution hazard, 0.6 [95% CI, 0.45-0.81]; P<0.001) were associated with reduced probability of favorable outcome. CONCLUSIONS: Repeat SRS confers reasonable obliteration rates with a low complication risk. With most complications occurring in the first 3 years, extending the latency period to 5 years generally increases the rate of favorable patient outcomes and reduces the necessity of a third intervention.


Asunto(s)
Malformaciones Arteriovenosas Intracraneales , Radiocirugia , Masculino , Humanos , Adulto , Femenino , Resultado del Tratamiento , Estudios de Seguimiento , Estudios Retrospectivos , Radiocirugia/efectos adversos , Radiocirugia/métodos , Malformaciones Arteriovenosas Intracraneales/diagnóstico por imagen , Malformaciones Arteriovenosas Intracraneales/radioterapia , Malformaciones Arteriovenosas Intracraneales/cirugía
11.
J Am Chem Soc ; 2023 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-37029738

RESUMEN

Copper (Cu), a promising catalyst for electrochemical CO2 reduction (CO2R) to multi-electron reduction products, suffers from an unavoidable and uncontrollable reconstruction process during the reaction, which not only may lead to catalyst deactivation but also brings great challenges to the exploration of the structure-performance relationship. Herein, we present an efficient strategy for stabilizing Cu with silica and synthesize reconstruction-resistant CuSiOx amorphous nanotube catalysts with abundant atomic Cu-O-Si interfacial sites. The strong interfacial interaction between Cu and silica makes the Cu-O-Si interfacial sites ultrastable in the CO2R reaction without any apparent reconstruction, thus exhibiting high CO2-to-CH4 selectivity (72.5%) and stability (FECH4 remains above 60% after 12 h of test). A remarkable CO2-to-CH4 conversion rate of 0.22 µmol cm-2 s-1 was also achieved in a flow cell device. This work provides a very promising route for the design of highly active and stable Cu-based CO2R catalysts.

12.
J Am Chem Soc ; 145(39): 21273-21283, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37729633

RESUMEN

Introducing a second metal species into atomically dispersed metal-nitrogen-carbon (M-N-C) catalysts to construct diatomic sites (DASs) is an effective strategy to elevate their activities and stabilities. However, the common pyrolysis-based method usually leads to substantial uncertainty for the formation of DASs, and the precise identification of the resulting DASs is also rather difficult. In this regard, we developed a two-step specific-adsorption strategy (pyrolysis-free) and constructed a DAS catalyst featuring FeCo "molecular heterostructures" (FeCo-MHs). In order to rule out the possibility of the two apparently neighboring (in the electron microscopy image) Fe/Co atoms being dispersed respectively on the top/bottom surfaces of the carbon support and thus forming "false" MHs, we conducted in situ rotation (by 8°, far above the critical angle of 5.3°) and directly identified the individual FeCo-MHs. The formation of FeCo-MHs could modulate the magnetic moments of the metal centers and increase the ratio of low-spin Fe(II)-N4 moiety; thus the intrinsic activity could be optimized at the apex of the volcano-plot (a relationship as a function of magnetic moments of metal-phthalocyanine complexes and catalytic activities). The FeCo-MHs catalyst displays an exceptional ORR activity (E1/2 = 0.95 V) and could be used to construct high-performance cathodes for hydroxide exchange membrane fuel cells and zinc-air batteries.

13.
Anal Chem ; 95(44): 16392-16397, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37885198

RESUMEN

Photocurrent polarity reversal is a switching process between the anodic and cathodic pathways and is critical for eliminating false positivity and improving detection sensitivity in photoelectrochemical (PEC) sensing. In this study, we construct a PEC sensor with excellent photocurrent polarity reversal induced by ascorbic acid (AA) as an electron donor with the energy level matching the photoactive material zirconium metal-organic framework (ZrMOF). The ZrMOF-modified electrode demonstrates cathodic photocurrent in the presence of O2 as an electron acceptor, while the anodic photocurrent is generated in the presence of AA, achieving photocurrent polarity reversal. By the in situ release of AA from AA-encapsulated apoferritin modified with DNA 2 (AA@APO-S2) as a detection tag in the presence of trypsin after the recognition of hairpin DNA-modified indium tin oxide to the reaction product of aptamer/DNA 1 with the target protein and the following rolling cycle amplification for introducing the detection tag to the sensing interface, the reversed photocurrent shows an enhanced photocurrent response to the target protein, leading to a highly sensitive PEC sensing strategy. This strategy realizes the detection of vascular endothelial growth factor 165 with good specificity, a wide linear range, and a low detection limit down to 5.3 fM. The actual sample analysis offers the detection results of the proposed PEC sensor comparable to those of commercial enzyme-linked immunosorbent assay tests, indicating the promising application of the photocurrent polarity reversal-based PEC sensing strategy in biomolecule detection and clinical diagnosis.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Factor A de Crecimiento Endotelial Vascular/análisis , Electrones , ADN , Aptámeros de Nucleótidos/química , Técnicas Electroquímicas/métodos , Límite de Detección
14.
BMC Cancer ; 23(1): 5, 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36597055

RESUMEN

BACKGROUND: It has been reported that inflammatory and nutritional markers are related to prognosis in numerous malignancies. The present study analyzed the significance of these markers' alterations during neoadjuvant chemotherapy in the long-term outcomes in patients with advanced gastric cancer. METHODS: A retrospective review was performed of 437 advanced gastric cancer patients who underwent a neoadjuvant chemotherapy (NACT) regimen followed by surgical treatment. Inflammatory and nutritional markers measured from the blood samples collected from the patients before the first neoadjuvant chemotherapy and after the last neoadjuvant chemotherapy were used for analysis. Statistical analysis, including Mann-Whitney U or chi-square tests, the Kaplan-Meier method and Cox multivariate analysis, were performed to analyze the predictive value of these markers for overall survival outcomes (OS). RESULTS: Most biomarkers, including lymphocyte, leucocyte, neutrophil, monocyte, platelet, LMR, PLR, SII, CRP, CAR, hemoglobulin and albumin levels, changed during NACT (P <  0.05). After separately grouping the patients based on the normal range of hematologic indexes and the change rate (α) of systemic inflammatory and nutritional markers by the cutoff value derived from X-tile (P <  0.05), we found that differentiation, TRG, pre-NACT BMI, pre-NACT platelet counts, post-NACT lymphocyte counts, the change in lymphocyte counts, change in platelet counts and LMR(α), PLR(α), SII(α), and CAR(α) were associated with OS. Multivariate analysis revealed that PLR (α) > - 19% was correlated with a 3.193-fold (95% CI: 2.194-4.649) higher risk of death (P <  0.001) than others. CONCLUSION: NACT could significantly change several inflammatory and nutritional markers in the perioperative period; the platelet counts before NACT, and the change in lymphocytes during NACT truly correlated with long-term outcomes among patients with advanced gastric cancer. The systemic inflammatory marker PLR may be a reliable marker for the prediction of prognosis.


Asunto(s)
Neoplasias Gástricas , Humanos , Pronóstico , Neoplasias Gástricas/tratamiento farmacológico , Linfocitos/patología , Recuento de Linfocitos , Neutrófilos/patología , Estudios Retrospectivos , Periodo Perioperatorio
15.
Soft Matter ; 19(2): 258-267, 2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36511950

RESUMEN

Non-Newtonian fluid rheological properties are a hot research topic for realizing intelligent applications. In order to investigate the microscopic mechanism and structural evolution process of the nonlinear rheological behavior of non-Newtonian fluids, this paper systematically investigates two continuous nonlinear rheological behaviors of non-Newtonian fluids, namely shear-thickening and shear-thinning rheological properties, using a non-Newtonian fluid system composed of polyethylene glycol (PEG) mixed with nano-silica (Nano-SiO2) by a dissipative particle dynamics (DPD) method. It is shown that at low shear rates, the molecular chains of PEG in the fluid are stretched due to shear flow and the molecular structure is transformed into an ordered state; and the effective hydrodynamic radius of Nano-SiO2 beads decreases, which makes the translational friction coefficient of the beads decrease and the system mobility increases, exhibiting shear-thinning behavior. When the shear rate exceeds the critical value, the contact and collision probability between Nano-SiO2 beads in the non-Newtonian fluid increases; a large number of silicon hydroxyl groups exist on the surface of Nano-SiO2, which form a large number of hydrogen bonds when they are close to each other and constrain the particle separation, resulting in a large aggregation of Nano-SiO2 beads, leading to an increase in the effective kinetic radius of Nano-SiO2 beads and an increase in the coefficient of translational friction, forming a blockage of the fluid system and exhibiting a shear-thickening behavior. Our study provides insights for understanding the rheological behavior of non-Newtonian fluids from a microscopic perspective, and contributes to the intelligent application of non-Newtonian fluids.

16.
Pituitary ; 26(1): 124-131, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36471108

RESUMEN

PURPOSE: Stereotactic radiosurgery (SRS) can be used in acromegaly patients to achieve endocrine remission. In this study we evaluate the biological effective dose (BED) as a predictor of SRS outcomes for acromegaly. METHOD: This retrospective, single-center study included patients treated with single-fraction SRS with growth hormone secreting pituitary adenomas and available endocrine follow-up. Kaplan-Meier analysis was used to study endocrine remission, new pituitary deficit, and tumor control. Cox analyses were performed using two models [margin dose (model 2) versus BED (model 1)]. RESULTS: Sixty-seven patients (53.7% male) with a median age of 46.8 years (IQR 21.2) were treated using a median dose of 25 Gy (IQR 5), and a median BED of 171.9Gy2.47 (IQR 66.0). Five (7.5%) were treated without stopping antisecretory medication. The cumulative probability of maintained endocrine remission off suppressive medications was 62.5% [47.9-73.0] at 3 years and 76.5% [61.0-85.9] at 5 years. IGF1i > 1.5 was a predictor of treatment failure [Hazard ratio (HR) 0.40 (0.21-0.79) in model 1, p = 0.00783]. Margin dose > 22 Gy [HR 2.33 (1.06-5.13), p = 0.03593] or a BED > 170Gy2.47 [HR 2.02 (1.06-3.86), p = 0.03370] were associated with endocrine remission. The cumulative probability of new hypopituitarism after SRS was 36.8% (CI 95% 22.4-45.9) at 3 years and 53.2% (CI 95% 35.6-66) at 5 years. BED or margin dose were not associated with new hypopituitarism. CONCLUSION: BED is a strong predictor of endocrine remission in patients treated with SRS. Dose planning and optimization of the BED to > 170Gy2.47 give a greater probability of endocrine remission in acromegalic patients.


Asunto(s)
Acromegalia , Adenoma , Hipopituitarismo , Radiocirugia , Femenino , Humanos , Masculino , Acromegalia/radioterapia , Acromegalia/cirugía , Acromegalia/complicaciones , Adenoma/radioterapia , Adenoma/cirugía , Adenoma/complicaciones , Estudios de Seguimiento , Hipopituitarismo/etiología , Radiocirugia/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento , Persona de Mediana Edad
17.
Acta Neurochir (Wien) ; 165(1): 211-220, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36543963

RESUMEN

BACKGROUND: Surgery is the preferred treatment for large vestibular schwannomas (VS). Good tumor control and cranial nerve outcomes were described in selected Koos IV VS after single-session stereotactic radiosurgery (SRS), but outcomes in elderly patients have never been specifically studied. The aim of this study is to report clinical and radiological outcomes after single-session SRS for Koos IV VS in patients ≥ 65 years old. METHOD: This multicenter, retrospective study included patients ≥ 65 years old, treated with primary, single-session SRS for a Koos IV VS, and at least 12 months of follow-up. Patients with life-threatening or incapacitating symptoms were excluded. Tumor control rate, hearing, trigeminal, and facial nerve function were studied at last follow-up. RESULTS: One-hundred and fifty patients (median age of 71.0 (IQR 9.0) years old with a median tumor volume of 8.3 cc (IQR 4.4)) were included. The median prescription dose was 12.0 Gy (IQR 1.4). The local tumor control rate was 96.0% and 86.2% at 5 and 10 years, respectively. Early tumor expansion occurred in 6.7% and was symptomatic in 40% of cases. A serviceable hearing was present in 16.1% prior to SRS and in 7.4% at a last follow-up of 46.5 months (IQR 55.8). The actuarial serviceable hearing preservation rate was 69.3% and 50.9% at 5 and 10 years, respectively. Facial nerve function preservation or improvement rates at 5 and 10 years were 98.7% and 91.0%, respectively. At last follow-up, the trigeminal nerve function was improved in 14.0%, stable in 80.7%, and worsened in 5.3% of the patients. ARE were noted in 12.7%. New hydrocephalus was seen in 8.0% of patients. CONCLUSION: SRS can be a safe alternative to surgery for selected Koos IV VS in patients ≥ 65 years old. Further follow-up is warranted.


Asunto(s)
Neuroma Acústico , Radiocirugia , Humanos , Anciano , Niño , Neuroma Acústico/diagnóstico por imagen , Neuroma Acústico/radioterapia , Neuroma Acústico/cirugía , Estudios Retrospectivos , Estudios de Seguimiento , Resultado del Tratamiento , Radiocirugia/efectos adversos
18.
Nano Lett ; 22(7): 2874-2880, 2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35315668

RESUMEN

Inorganic CsPbI3 perovskite has shown great promise in highly stable perovskite solar cells due to the lack of volatile organic components. However, the inferior phase stability in ambient conditions resulted from the very small Cs+, limiting their practical applications. Here, CsPbI3-based 2D Ruddlesden-Popper (RP) perovskites were developed using two thiophene-based aromatic spacers, namely, 2-thiophenemethylamine hydroiodide (ThMA) and 2-thiopheneformamidine hydroiodide (ThFA), which significantly improved the phase stability by releasing the large inner stress of black-phase CsPbI3. The optimized ThFA-based 2D RP perovskite (n = 5, ThFA-Cs) device achieves a record efficiency of 16.00%. Importantly, the ThFA-Cs devices could maintain an average of 98% of their initial efficiencies after being stored in N2 at room temperature for 3000 h and 92% of their initial value at 80 °C for 960 h. This work provides a new perspective for exploration of the phase-stable CsPbI3-based perovskite with reduced dimensions for high-performance solar cells.

19.
Molecules ; 28(2)2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36677619

RESUMEN

Thirty novel diamide compounds combining pyrazolyl and polyfluoro-substituted phenyl groups into alanine or 2-aminobutyric acid skeletons were designed and synthesized with pyflubumide as the lead compound to develop potent and environmentally friendly pesticides. The preliminary bioassay results indicated that the new compounds containing the para-hexa/heptafluoroisopropylphenyl moiety exhibit fungicidal, insecticidal, and acaricidal activities. This is the first time that the para-hexa/heptafluoroisopropylphenyl group is a key fragment of the fungicidal activity of new N-phenyl amide compounds. Most of the target compounds exhibited moderate to good insecticidal activity against Aphis craccivora at a concentration of 400 µg/mL, and some showed moderate activity at a concentration of 200 µg/mL; in particular, compounds I-4, II-a-10, and III-26 displayed higher than 78% lethal rates at 200 µg/mL. Compound II-a-14 exhibited a 61.1% inhibition at 200 µg/mL for Tetranychus cinnabarinus. In addition, some of the target compounds exhibited good insecticidal activities against Plutella xylostella at a concentration of 200 µg/mL; the mortalities of compounds I-1, and II-a-15 were 76.7% and 70.0%, respectively. Preliminary analysis of the structure-activity relationship (SAR) indicated that the insecticidal and acaricidal activities varied significantly depending on the type of substituent and substitution pattern. The fungicidal activity results showed that compounds I-1, II-a-10, II-a-17, and III-26 exhibited good antifungal effects. Enzymatic activity experiments and in vivo efficacy of compound II-a-10 were conducted and discussed.


Asunto(s)
Acaricidas , Fungicidas Industriales , Insecticidas , Mariposas Nocturnas , Animales , Insecticidas/farmacología , Diamida/farmacología , Alanina/farmacología , Diseño de Fármacos , Relación Estructura-Actividad , Fungicidas Industriales/farmacología , Estructura Molecular
20.
Molecules ; 28(3)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36771096

RESUMEN

Picolinic acid and picolinate compounds are a remarkable class of synthetic auxin herbicides. In recent years, two new picolinate compounds, halauxifen-methyl (ArylexTM active) and florpyrauxifen-benzyl (RinskorTM active), have been launched as novel herbicides. Using their structural skeleton as a template, 33 4-amino-3,5-dicholor-6-(5-aryl-substituted-1-pytazolyl)-2-picolinic acid compounds were designed and synthesized for the discovery of compounds with potent herbicidal activity. The compounds were tested for inhibitory activity against the growth of Arabidopsis thaliana roots, and the results demonstrated that the IC50 value of compound V-7 was 45 times lower than that of the halauxifen-methyl commercial herbicide. Molecular docking analyses revealed that compound V-7 docked with the receptor auxin-signaling F-box protein 5 (AFB5) more intensively than picloram. An adaptive three-dimensional quantitative structure-activity relationship model was constructed from these IC50 values to guide the next step of the synthetic strategy. Herbicidal tests of the new compounds indicated that compound V-8 exhibited better post-emergence herbicidal activity than picloram at a dosage of 300 gha-1, and it was also safe for corn, wheat, and sorghum at this dosage. These results demonstrated that 6-(5-aryl-substituted-1-pyrazolyl)-2-picolinic acid compounds could be used as potential lead structures in the discovery of novel synthetic auxin herbicides.


Asunto(s)
Arabidopsis , Herbicidas , Herbicidas/química , Picloram , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo
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