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1.
Small ; 20(14): e2307776, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37990379

RESUMEN

The high-performance and sustainable electrocatalysts toward oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are essential for rechargeable Zn-air batteries (ZABs). In this paper, a natural all-components bamboo is provided as the carbon source, and melamine and cobalt chloride are provided as the nitrogen and cobalt sources, respectively. As a result, the unique helical carbon nanotubes (HCNTs) encapsulated cobalt nanoparticles are prepared, which are acted as ORR/OER electrocatalysts to improve ZABs performance. The resultant HCNTs contribute to high ORR/OER activities via exposing more Co─N sites, providing excellent electron conductivity, and facilitating mass transfer of the reactant. The HCNTs assembled rechargeable liquid ZABs showed a maximum output power density of 226 mW cm-2 and a low voltage gap of 0.85 V for 330 h cycles. The flexible all-solid-state ZABs achieved the maximum power density with 59.4 mW cm-2 and charge-discharge cycles over 25 h. The density functional theory (DFT) calculations reveal that the increase of Co─N at HCNTs effectively regulates the electronic structure of Co, optimizing the binding affinity of oxygen intermediates and resulting in the low ORR/OER overpotentials. This work paves the way for transforming renewable bamboo biomass into versatile electrocatalysts, which boosts the development of next-generation energy storage and conversion devices.

2.
Chemistry ; 30(35): e202401150, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38639722

RESUMEN

In this study, a series of H-bonded arylamide foldamers bearing benzoselenadiazole ends with solvent-responsive properties have been synthesized. In dichloromethane or dimethyl sulfoxide solvents, the molecules exhibit meniscus or linear structures, respectively, which can be attributed to the unique intramolecular hydrogen bonding behavior evidenced by 1D 1H NMR and 2D NOESY spectra. UV-vis spectroscopy experiments show that the absorption wavelength of H-bonded arylamide foldamers are significantly red-shifted due to the presence of benzoselenadiazole group. In addition, the crystal structures reveal that effective intermolecular dual Se ⋅ ⋅ ⋅ N interactions between benzoselenadiazole groups induce further assembly of the monomers. Remarkably, supramolecular linear and double helices structures are constructed under the synergistic induction of intramolecular hydrogen bonding and intermolecular chalcogen bonding. Additionally, 2D DOSY diffusion spectra and theoretical modelling based on density functional theory (DFT) are performed to explore the persistence of intermolecular Se ⋅ ⋅ ⋅ N interactions beyond the crystalline state.

3.
Inorg Chem ; 63(27): 12516-12524, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38917357

RESUMEN

Chemiresistive NH3/NO2 sensors are attracting considerable attention for use in air-conditioning systems. However, the existing sensors suffer from cross-sensitivity, detection limit, and power consumption, owing to the inadequate charge-transfer ability of gas-sensing materials. Herein, we develop a flexible NH3/NO2 sensor based on graphitic carbon nitride/polypyrrole decorated alginate paper (AP@g-CN/PPy). The flexible sensor can work at room temperature and exhibits a positive response of 23-246% and a negative response of 37-262% toward 0.1-5 ppm of NH3 and NO2, which is ∼4.5 times and ∼7.0 times higher than a pristine PPy sensor. Moreover, the sensor exhibits flexibility, reproducibility, long-term stability, anti-interference, and high resilience to humidity, indicating its promising potential in real applications. Using the 9 feature parameters extracted from the transient response, a matched deep learning model was developed to achieve qualitative recognition of different types of gases with distinguished decision boundaries. This work not only provides an alternative gas-sensing material for dual NH3/NO2 sensing but also establishes an intelligent strategy to identify hazardous gases under an interfering atmosphere.

4.
Sensors (Basel) ; 24(7)2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38610547

RESUMEN

Visual transformers (ViTs) are widely used in various visual tasks, such as fine-grained visual classification (FGVC). However, the self-attention mechanism, which is the core module of visual transformers, leads to quadratic computational and memory complexity. The sparse-attention and local-attention approaches currently used by most researchers are not suitable for FGVC tasks. These tasks require dense feature extraction and global dependency modeling. To address this challenge, we propose a dual-dependency attention transformer model. It decouples global token interactions into two paths. The first is a position-dependency attention pathway based on the intersection of two types of grouped attention. The second is a semantic dependency attention pathway based on dynamic central aggregation. This approach enhances the high-quality semantic modeling of discriminative cues while reducing the computational cost to linear computational complexity. In addition, we develop discriminative enhancement strategies. These strategies increase the sensitivity of high-confidence discriminative cue tracking with a knowledge-based representation approach. Experiments on three datasets, NABIRDS, CUB, and DOGS, show that the method is suitable for fine-grained image classification. It finds a balance between computational cost and performance.

5.
J Am Chem Soc ; 145(2): 1144-1154, 2023 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-36538569

RESUMEN

Remolding the reactivity of metal active sites is critical to facilitate renewable electricity-powered water electrolysis. Doping heteroatoms, such as Se, into a metal crystal lattice has been considered an effective approach, yet usually suffers from loss of functional heteroatoms during harsh electrocatalytic conditions, thus leading to the gradual inactivation of the catalysts. Here, we report a new heteroatom-containing molecule-enhanced strategy toward sustainable oxygen evolution improvement. An organoselenium ligand, bis(3,5-dimethyl-1H-pyrazol-4-yl)selenide containing robust C-Se-C covalent bonds equipped in the precatalyst of ultrathin metal-organic nanosheets Co-SeMON, is revealed to significantly enhance the catalytic mass activity of the cobalt site by 25 times, as well as extend the catalyst operation time in alkaline conditions by 1 or 2 orders of magnitude compared with these reported metal selenides. A combination of various in situ/ex situ spectroscopic techniques, ab initio molecular dynamics, and density functional theory calculations unveiled the organoselenium intensified mechanism, in which the nonclassical bonding of Se to O-containing intermediates endows adsorption-energy regulation beyond the conventional scaling relationship. Our results showcase the great potential of molecule-enhanced catalysts for highly efficient and economical water oxidation.


Asunto(s)
Cobalto , Metales , Adsorción , Oxígeno , Agua
6.
Inorg Chem ; 62(7): 3297-3304, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36758163

RESUMEN

Remodeling the active surface through fabricating heterostructures can substantially enhance alkaline water electrolysis driven by renewable electrical energy. However, there are still great challenges in the synthesis of highly reactive and robust heterostructures to achieve both ampere-level current density hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, we report a new Co/CeO2 heterojunction self-supported electrode for sustainable overall water splitting. The self-supporting Co/CeO2 heterostructures required only low overpotentials of 31.9 ± 2.2, 253.3 ± 2.7, and 316.7 ± 3 mV for HER and 214.1 ± 1.4, 362.3 ± 1.9, and 400.3 ± 3.7 mV for OER at 0.01, 0.5, and 1.0 A·cm-2, respectively, being one of the best Co-based bifunctional electrodes. Electrolyzer constructed from this electrode acting as an anode and cathode merely required cell voltages of 1.92 ± 0.02 V at 1.0 A·cm-2 for overall water splitting. Multiple characterization techniques combined with density functional theory calculations disclosed the different active sites on the anode and cathode, and the charge redistributions on the heterointerfaces that can optimize the adsorption of H and oxygen-containing intermediates, respectively. This study presents the tremendous prospective of self-supporting heterostructures for effective and economical overall water splitting.

7.
Dig Dis Sci ; 68(3): 948-956, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35731426

RESUMEN

BACKGROUND: The apheresis technique is increasingly used in patients with hypertriglyceridemia-induced pancreatitis (HTGP), while its role in this context is still not well established. Thus, we aimed to evaluate the clinical outcomes of an apheresis therapy compared to usual care in such a patient population. METHODS: We searched PubMed, Embase, and Cochrane library databases up to July 10, 2021. Studies were included if they focused on HTGP treated with or without apheresis technique. We used the Newcastle-Ottawa Scale to assess the quality of the included studies. The primary outcome was the mortality rate. We also explored the heterogeneity, sensitivity analysis, subgroup analysis, and publication bias. RESULTS: Sixteen observational studies with 1476 adults were included. The overall quality of included studies was moderate. Despite better TG level reduction with apheresis therapy (mean difference [MD], 12.27 mmol/L, 95% CI, 3.74 to 20.81; I2 = 78%; P = 0.005), use of apheresis did not reduce the mortality (odds ratio [OR], 1.01; 95% CI, 0.65 to 1.59; P = 0.95) compared with usual care. This result was further confirmed by sensitivity analysis, subgroup analysis. The length of stay in hospital (MD, 0.96 days; 95% CI, - 1.22 to 3.14; I2 = 70%; P = 0.39) and most complications were similar between the groups, while hospital cost was significantly higher in the apheresis group. CONCLUSIONS: The apheresis technique did not decrease the mortality in HTGP patients compared with usual care. Until the results of high-quality RCTs are known, these findings do not support the routine use of the apheresis technique in such a patient population.


Asunto(s)
Eliminación de Componentes Sanguíneos , Hipertrigliceridemia , Pancreatitis , Adulto , Humanos , Eliminación de Componentes Sanguíneos/efectos adversos , Eliminación de Componentes Sanguíneos/métodos , Hipertrigliceridemia/complicaciones , Pancreatitis/etiología , Pancreatitis/terapia
8.
Proc Natl Acad Sci U S A ; 117(27): 15517-15523, 2020 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-32554603

RESUMEN

Topological electrons in semimetals are usually vulnerable to chemical doping and environment change, which restricts their potential application in future electronic devices. In this paper, we report that the type-II Dirac semimetal [Formula: see text] hosts exceptional, robust topological electrons which can tolerate extreme change of chemical composition. The Dirac electrons remain intact, even after a substantial part of V atoms have been replaced in the [Formula: see text] solid solutions. This Dirac semimetal state ends at [Formula: see text], where a Lifshitz transition to p-type trivial metal occurs. The V-Al bond is completely broken in this transition as long as the bonding orbitals are fully depopulated by the holes donated from Ti substitution. In other words, the Dirac electrons in [Formula: see text] are protected by the V-Al bond, whose molecular orbital is their bonding gravity center. Our understanding on the interrelations among electron count, chemical bond, and electronic properties in topological semimetals suggests a rational approach to search robust, chemical-bond-protected topological materials.

9.
Chem Biodivers ; 20(12): e202301512, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37921566

RESUMEN

Four new phomalones A-D (1-4), together with five known analogues (5-9) were isolated from the deep-sea-derived fungus Trichobotrys effuse FS522. Their structures of the new compounds established by analysis of their NMR and HR-ESI-MS spectroscopic data, and the absolute configurations of 2 was determined by electronic circular dichroism (ECD) calculations. compounds 4, 6 and 8 substantially inhibited the production of nitric oxide (NO) with IC50 values of 4.64, 13.90, and 34.07 µM.


Asunto(s)
Ascomicetos , Antiinflamatorios/farmacología , Espectroscopía de Resonancia Magnética/métodos , Estructura Molecular , Piranos/química , Piranos/farmacología , Compuestos Heterocíclicos con 3 Anillos/química , Compuestos Heterocíclicos con 3 Anillos/farmacología
10.
Sensors (Basel) ; 23(10)2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37430848

RESUMEN

In wearable robots, the application of surface electromyography (sEMG) signals in motion intention recognition is a hot research issue. To improve the viability of human-robot interactive perception and to reduce the complexity of the knee joint angle estimation model, this paper proposed an estimation model for knee joint angle based on the novel method of multiple kernel relevance vector regression (MKRVR) through offline learning. The root mean square error, mean absolute error, and R2_score are used as performance indicators. By comparing the estimation model of MKRVR and least squares support vector regression (LSSVR), the MKRVR performs better on the estimation of the knee joint angle. The results showed that the MKRVR can estimate the knee joint angle with a continuous global MAE of 3.27° ± 1.2°, RMSE of 4.81° ± 1.37°, and R2 of 0.8946 ± 0.07. Therefore, we concluded that the MKRVR for the estimation of the knee joint angle from sEMG is viable and could be used for motion analysis and the application of recognition of the wearer's motion intentions in human-robot collaboration control.


Asunto(s)
Intención , Articulación de la Rodilla , Humanos , Electromiografía , Aprendizaje , Movimiento (Física)
11.
Org Biomol Chem ; 20(5): 1095-1102, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35019920

RESUMEN

We report here that polysubstituted cyclopent-2-enols can be constructed by the one-pot reaction of doubly activated cyclopropanes and α-EWG substituted acetonitriles under mild basic conditions via a domino-ring-opening-cyclization/deacylation/oxidation sequence. Moreover, the synthetic applications of these cyclopent-2-enols have been demonstrated in the late-stage derivatization into functionalized cyclopentapyrimidin-4-ones and 2-hydroxy cyclopentanones with good yields.

12.
Clin Lab ; 68(3)2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35254038

RESUMEN

BACKGROUND: Over past decades, the instability of parathyroid hormone (PTH) causes great interference for the clinical laboratory. Contradictory results were reported in many reports about storage conditions and suitable blood collection tubes to ensure PTH stability in the pretreatment phase. METHODS: This study recruited 30 participants including 10 healthy persons, 10 hemodialysis, and 10 hyperparathyroidism patients. Five types of blood collection tubes (EDTA-K3 tube, coagulant tube, heparin anticoagulant tube, gel separating tube, and plain tube) were included to determine whether they were suitable as blood-collecting vessels. The time points and conditions for testing samples included less than 2 hours, 4 hours, and 8 hours at room temperature, and, in parallel, 24 hours, 48 hours, and 72 hours in refrigeration. Two different judgement criteria were used to compare the stability of PTH in different blood vessels. RESULTS: Purely statistical analysis showed that 4 types of blood collection tubes could not perform the same storage ability as EDTA-K3 tube at "T0" time point. Plain tube had the largest drop among all types of blood collection tubes. Compared by pairwise t-test, EDTA-K3 tube could maintain intact PTH for 8 hours (p = 0.998) at room temperature and 24 hours (p = 0.053) in refrigeration. When comparing the total change limit (TCL = 18.8%), at room temperature, EDTA-K3 tube (7.0%), heparin tube (12.7%), coagulant tube (16.2%), and plain tube (17.6%) could maintain intact PTH for 8 hours, and GST can preserve PTH for 4 hours (18.2%). In refrigeration, EDTA-K3 tube could maintain PTH for 72 hours (7.5%) and heparin tube could maintain 24 hours (18.4%). The other three blood collection tubes could not preserve PTH in refrigeration (GST = 22.1%, coagulant tube = 20.3%, plain tube = 20.8%). CONCLUSIONS: PTH seems more stable in the EDTA-K3 tube than any other blood collection tubes and is followed next by the heparin anticoagulant tube. Plain tube and GST have faster degradation than other tubes and are not suggested to preserve intact PTH.


Asunto(s)
Recolección de Muestras de Sangre , Hormona Paratiroidea , Anticoagulantes , Recolección de Muestras de Sangre/métodos , Ácido Edético , Pruebas Hematológicas/métodos , Humanos , Diálisis Renal
13.
Ann Hepatol ; 27(6): 100745, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35964909

RESUMEN

INTRODUCTION AND OBJECTIVES: Hepatitis B surface antigen (HBsAg) clearance, indicating functional cure or resolved chronic hepatitis B (CHB), remains difficult to achieve via nucleos(t)ide analogue monotherapy. We investigated whether metformin add-on therapy could help achieve this goal in entecavir-treated patients with hepatitis B e antigen (HBeAg)-negative CHB. PATIENTS AND METHODS: Patients with HBeAg-negative CHB who met eligibility criteria (entecavir treatment for > 12 months, HBsAg < 1000 IU/mL) were randomly assigned (1:1) to receive 24 weeks of either metformin (1000 mg, oral, once a day) or placebo (oral, once a day) add-on therapy. The group allocation was blinded for both patients and investigators. Efficacy and safety analyses were based on the intention-to-treat set. The primary outcome, serum HBsAg level (IU/mL) at weeks 24 and 36, was analysed using mixed models. RESULTS: Sixty eligible patients were randomly assigned to the metformin (n = 29) and placebo (n = 31) groups. There was no substantial between-group difference in the HBsAg level at week 24 (adjusted mean difference 0.05, 95% confidence interval -0.04 to 0.13, p = 0.278) or week 36 (0.06, -0.03 to 0.15, p = 0.187), and no significant effect of group-by-time interaction on the HBsAg level throughout the trial (p = 0.814). The occurrence of total adverse events between the two groups was comparable (9 [31.0%] of 29 vs. 5 [16.1%] of 31, p = 0.227) and no patient experienced serious adverse events during the study. CONCLUSION: Although it was safe, metformin add-on therapy did not accelerate HBsAg clearance in entecavir-treated patients with HBeAg-negative CHB.


Asunto(s)
Hepatitis B Crónica , Metformina , Humanos , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/tratamiento farmacológico , Antígenos e de la Hepatitis B , Antígenos de Superficie de la Hepatitis B , Metformina/efectos adversos , Antivirales/efectos adversos , ADN Viral , Virus de la Hepatitis B/genética , Resultado del Tratamiento
14.
Angew Chem Int Ed Engl ; 61(29): e202205534, 2022 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-35488890

RESUMEN

A water-soluble cavitand bearing a benzotriazole upper rim was prepared and characterized. It exists as a dimeric velcraplex in D2 O, but forms host-guest complexes with hydrophobic and amphiphilic guests. Alkanes (C5 to C10), cyclic ketones (C6-C10), cyclic alcohols (C6-C8) and various amphiphilic guests form 1 : 1 cavitand complexes. A cyclic array of hydrogen bonds, bridged by solvent/water (D2 O) molecules, stabilizes the vase conformation of the complexes. With longer alkanes (C12-C15), symmetrical dialkyl amine, urea and phosphate, 2 : 1 host:guest capsules are formed. Computations indicate that additional waters on the upper rim create a self-complementary hydrogen-bonding pattern for capsule formation.


Asunto(s)
Alcanos , Agua , Alcanos/química , Éteres Cíclicos , Modelos Moleculares , Resorcinoles , Triazoles , Agua/química
15.
Circulation ; 142(12): 1159-1172, 2020 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-32683896

RESUMEN

BACKGROUND: Enhanced diastolic calcium (Ca2+) release through ryanodine receptor type-2 (RyR2) has been implicated in atrial fibrillation (AF) promotion. Diastolic sarcoplasmic reticulum Ca2+ leak is caused by increased RyR2 phosphorylation by PKA (protein kinase A) or CaMKII (Ca2+/calmodulin-dependent kinase-II) phosphorylation, or less dephosphorylation by protein phosphatases. However, considerable controversy remains regarding the molecular mechanisms underlying altered RyR2 function in AF. We thus aimed to determine the role of SPEG (striated muscle preferentially expressed protein kinase), a novel regulator of RyR2 phosphorylation, in AF pathogenesis. METHODS: Western blotting was performed with right atrial biopsies from patients with paroxysmal AF. SPEG atrial knockout mice were generated using adeno-associated virus 9. In mice, AF inducibility was determined using intracardiac programmed electric stimulation, and diastolic Ca2+ leak in atrial cardiomyocytes was assessed using confocal Ca2+ imaging. Phosphoproteomics studies and Western blotting were used to measure RyR2 phosphorylation. To test the effects of RyR2-S2367 phosphorylation, knockin mice with an inactivated S2367 phosphorylation site (S2367A) and a constitutively activated S2367 residue (S2367D) were generated by using CRISPR-Cas9. RESULTS: Western blotting revealed decreased SPEG protein levels in atrial biopsies from patients with paroxysmal AF in comparison with patients in sinus rhythm. SPEG atrial-specific knockout mice exhibited increased susceptibility to pacing-induced AF by programmed electric stimulation and enhanced Ca2+ spark frequency in atrial cardiomyocytes with Ca2+ imaging, establishing a causal role for decreased SPEG in AF pathogenesis. Phosphoproteomics in hearts from SPEG cardiomyocyte knockout mice identified RyR2-S2367 as a novel kinase substrate of SPEG. Western blotting demonstrated that RyR2-S2367 phosphorylation was also decreased in patients with paroxysmal AF. RyR2-S2367A mice exhibited an increased susceptibility to pacing-induced AF, and aberrant atrial sarcoplasmic reticulum Ca2+ leak, as well. In contrast, RyR2-S2367D mice were resistant to pacing-induced AF. CONCLUSIONS: Unlike other kinases (PKA, CaMKII) that increase RyR2 activity, SPEG phosphorylation reduces RyR2-mediated sarcoplasmic reticulum Ca2+ release. Reduced SPEG levels and RyR2-S2367 phosphorylation typified patients with paroxysmal AF. Studies in S2367 knockin mouse models showed a causal relationship between reduced S2367 phosphorylation and AF susceptibility. Thus, modulating SPEG activity and phosphorylation levels of the novel S2367 site on RyR2 may represent a novel target for AF treatment.


Asunto(s)
Fibrilación Atrial/metabolismo , Señalización del Calcio , Proteínas Musculares/metabolismo , Miocardio/metabolismo , Quinasa de Cadena Ligera de Miosina/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Animales , Fibrilación Atrial/genética , Femenino , Humanos , Masculino , Ratones , Ratones Noqueados , Proteínas Musculares/genética , Quinasa de Cadena Ligera de Miosina/genética , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Canal Liberador de Calcio Receptor de Rianodina/genética , Retículo Sarcoplasmático/genética , Retículo Sarcoplasmático/metabolismo
16.
J Org Chem ; 86(13): 8873-8881, 2021 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-34114823

RESUMEN

We report the synthesis and characterization of a new water-soluble cavitand 1. The container features 2-aminobenzimidazole panels at the "rim" and pyridiniums at the "feet". In the solid state, a single-crystal X-ray structure of the organic-soluble precursor 2 showed a stable vase form. The structure is stabilized by hydrogen-bonded bridges between adjacent panels through solvents and ions. In aqueous solution, binding of hydrophobic and amphiphilic guest molecules to 1 was investigated using 1H NMR. Alkanes, alcohols, acids, diols, and diacids formed 1:1 host-guest complexes, and the guest conformations were deduced from characteristic chemical shift changes. In the presence of [Pd(ethylenediamine)(H2O)2·2NO3], cavitand 1 formed a complex incorporating two metals. The metal-coordinated cavitand also bound hydrophobic linear alkanes and difluorobenzene isomers in aqueous medium. The metallo-cavitand showed shape and size selectivity and was used to separate o-difluorobenzene from its isomers as observed by 19F NMR spectroscopy. The primary amino function of the cavitands offers possibilities for further elaboration to covalent clusters of these container compounds.


Asunto(s)
Agua , Interacciones Hidrofóbicas e Hidrofílicas , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Conformación Molecular
17.
Org Biomol Chem ; 19(14): 3191-3198, 2021 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-33885573

RESUMEN

We report here that a series of bridged O,O-ketal fused spiro piperidone-cyclopropane derivatives 3 can be constructed with excellent yields and good diastereoselectivity by the one-pot reaction of 1-acylcyclopropanecarboxamides 1 with electron-deficient alkene 2a (EWG = CHO) via the domino process involving [4 + 2] annulation/intermolecular electrophilic addition/intramolecular cyclization. Furthermore, reactions of 1 with 2b/2c (EWG = CN, COOMe), leading to spiro piperidone-cyclopropane derivatives 4 or 5 by base catalyst selection, were also presented.

18.
Crit Care ; 25(1): 88, 2021 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-33639997

RESUMEN

BACKGROUND: The use of indirect calorimetry (IC) is increasing due to its precision in resting energy expenditure (REE) measurement in critically ill patients. Thus, we aimed to evaluate the clinical outcomes of an IC-guided nutrition therapy compared to predictive equations strategy in such a patient population. METHODS: We searched PubMed, EMBASE, and Cochrane library databases up to October 25, 2020. Randomized controlled trials (RCTs) were included if they focused on energy delivery guided by either IC or predictive equations in critically ill adults. We used the Cochrane risk-of-bias tool to assess the quality of the included studies. Short-term mortality was the primary outcome. The meta-analysis was performed with the fixed-effect model or random-effect model according to the heterogeneity. RESULTS: Eight RCTs with 991 adults met the inclusion criteria. The overall quality of the included studies was moderate. Significantly higher mean energy delivered per day was observed in the IC group, as well as percent delivered energy over REE targets, than the control group. IC-guided energy delivery significantly reduced short-term mortality compared with the control group (risk ratio = 0.77; 95% CI 0.60 to 0.98; I2 = 3%, P = 0.03). IC-guided strategy did not significantly prolong the duration of mechanical ventilation (mean difference [MD] = 0.61 days; 95% CI - 1.08 to 2.29; P = 0.48), length of stay in ICU (MD = 0.32 days; 95% CI - 2.51 to 3.16; P = 0.82) and hospital (MD = 0.30 days; 95% CI - 3.23 to 3.83; P = 0.87). Additionally, adverse events were similar between the two groups. CONCLUSIONS: This meta-analysis indicates that IC-guided energy delivery significantly reduces short-term mortality in critically ill patients. This finding encourages the use of IC-guided energy delivery during critical nutrition support. But more high-quality studies are still needed to confirm these findings.


Asunto(s)
Calorimetría Indirecta/métodos , Apoyo Nutricional/métodos , Enfermedad Crítica/terapia , Metabolismo Energético , Humanos , Tiempo de Internación/tendencias
19.
Curr Microbiol ; 78(7): 2569-2576, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33978787

RESUMEN

After separation of bacterial colonies on solid plates, purification, and screening through the agar cup-plate method, an antibiotic-resistant bacterial isolate was obtained, and named strain L20190601, the 16S rRNA gene sequence data of strain L20190601 to GenBank, NCBI have provided GenBank accession number MW931615. 16S rRNA gene sequencing revealed that this isolate was highly similar to a number of Streptomyces species. Among them, the homology with S. spectabilis was the highest, reaching 99.9, together with curved hyphal morphology and biochemical tests, allowed us to identify strain L20190601 as S. spectabilis. The red pigment produced by S. spectabilis strain L20190601 was structurally identified. An acid-base color reaction assay showed that when this pigment was dissolved in a solution at pH 3.0 and 9.0, the color of the solution was red and yellow, respectively. In addition, the analysis of absorption spectra revealed that at pH 8.0 and 3.0, the maximum absorption peaks were at 466 and 531 nm, respectively. These results are consistent with the spectral absorption characteristics of metacycloprodigiosin reported in the literature. Moreover, the retention time of purified pigments was identical to those of standard metacycloprodigiosin solutions. Mass spectrometry analysis revealed that the molecular weight of the red compound was 392.2 [M + H]+. Finally, metacycloprodigiosin was found to be effective against eight clinically common pathogens: Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Streptococcus pyogenes, Pseudomonas aeruginosa, Bacillus typhi, Candida albicans, and Trichophyton rubrum. In summary, metacycloprodigiosin exhibited strong antibacterial activity and a broad antibacterial spectrum, and thus is a promising compound for the development of a new type of antibacterial drug.


Asunto(s)
Microbiología del Suelo , Streptomyces , Antibacterianos/farmacología , Arthrodermataceae , Pruebas de Sensibilidad Microbiana , Prodigiosina/análogos & derivados , ARN Ribosómico 16S/genética , Streptomyces/genética
20.
J Infect Dis ; 221(3): 389-399, 2020 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-31550363

RESUMEN

BACKGROUND: Patients on oral antiviral (OAV) therapy remain at hepatocellular carcinoma (HCC) risk. Risk prediction tools distinguishing treated patients with residual HCC risk are limited. The aim of this study was to develop an accurate, precise, simple-to-use HCC risk score using routine clinical variables among a treated Asian cohort. METHODS: Adult Asian chronic hepatitis B (CHB) patients on OAV were recruited from 25 centers in the United States and the Asia-Pacific region. Excluded persons were coinfected with hepatitis C, D, or human immunodeficiency virus, had HCC before or within 1 year of study entry, or their follow-up was <1 year. Patients were randomized to derivation and validation cohorts on a 2:1 ratio. Statistically significant predictors from multivariate modeling formed the Real-world Effectiveness from the Asia Pacific Rim Liver Consortium for HBV (REAL-B) score. RESULTS: A total of 8048 patients were randomized to the derivation (n = 5365) or validation group (n = 2683). The REAL-B model included 7 variables (male gender, age, alcohol use, diabetes, baseline cirrhosis, platelet count, and alpha fetoprotein), and scores were categorized as follows: 0-3 low risk, 4-7 moderate risk, and 8-13 high risk. Area under receiver operating characteristics were >0.80 for HCC risk at 3, 5, and 10 years, and these were significantly higher than other risk models (p < .001). CONCLUSIONS: The REAL-B score provides 3 distinct risk categories for HCC development in Asian CHB patients on OAV guiding HCC surveillance strategy.


Asunto(s)
Antivirales/efectos adversos , Antivirales/uso terapéutico , Carcinoma Hepatocelular/etiología , Virus de la Hepatitis B/genética , Hepatitis B Crónica/tratamiento farmacológico , Neoplasias Hepáticas/etiología , Proyectos de Investigación , Administración Oral , Adulto , Antivirales/administración & dosificación , Asia/etnología , Pueblo Asiatico , Estudios de Cohortes , ADN Viral/genética , Exactitud de los Datos , Femenino , Hepatitis B Crónica/etnología , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Curva ROC , Distribución Aleatoria , Medición de Riesgo
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