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1.
J Am Chem Soc ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978232

RESUMO

The development of architecturally unique molecular nanocarbons by bottom-up organic synthesis is essential for accessing functional organic materials awaiting technological developments in fields such as energy, electronics, and biomedicine. Herein, we describe the design and synthesis of a triptycene-based three-dimensional (3D) nanocarbon, GFN-1, with geometrical flexibility on account of its three peripheral π-panels being capable of interconverting between two curved conformations. An effective through-space electronic communication among the three π-panels of GFN-1 has been observed in its monocationic radical form, which exhibits an extensively delocalized spin density over the entire 3D π-system as revealed by electron paramagnetic resonance and UV-vis-NIR spectroscopies. The flexible 3D molecular architecture of GFN-1, along with its densely packed superstructures in the presence of fullerenes, is revealed by microcrystal electron diffraction and single-crystal X-ray diffraction, which establish the coexistence of both propeller and tweezer conformations in the solid state. GFN-1 exhibits strong binding affinities for fullerenes, leading to host-guest complexes that display rapid photoinduced electron transfer within a picosecond. The outcomes of this research could pave the way for the utilization of shape and electronically complementary nanocarbons in the construction of functional coassemblies.

2.
J Med Genet ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38964834

RESUMO

BACKGROUND: IFIH1 variants have been reported to be associated with immune-related disorders with/without seizures. It is unknown whether IFIH1 variants are associated with common epilepsy without acquired causes and the mechanism underlying phenotypic variation remains elusive. METHODS: Trio-based whole-exome sequencing was performed on patients with febrile seizures or epilepsy with antecedent febrile seizures. Previously reported variants were systematically reviewed to investigate genotype-phenotype associations. RESULTS: Two de novo heterozygous and three biallelic missense variants were identified in five patients with generalised epilepsy with antecedent febrile seizures. The variants were predicted to be damaging by in silico tools and were associated with hydrogen bonding changes to neighbouring amino acids or decreased protein stability. Patients exhibited an early onset age and became seizure-free with favourable outcome. Further analysis revealed that de novo missense variants located in the Hel region resulted in seizures with multiple neurological abnormalities, while those in the pincer domain or C-terminal domain led to seizures with normal neurodevelopment, suggesting a sub-molecular effect. Biallelic missense variants, which were inherited from unaffected parents and presented low allele frequencies in general populations, were associated with seizures without neurological abnormalities. Truncation variants were related to refractory epilepsy and severe developmental delay, suggesting a genotype-phenotype correlation. IFIH1 is predominantly expressed in the neonatal stage and decreases dramatically in the adulthood, which is consistent with the early onset age and favourable outcome of the patients. CONCLUSIONS: IFIH1 variants are potentially associated with generalised epilepsy with antecedent febrile seizures. The sub-molecular implication and genotype-phenotype association help explain phenotype variations of IFIH1 variants.

3.
Angew Chem Int Ed Engl ; 63(22): e202402255, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38551062

RESUMO

With the prosperity of the development of carbon nanorings, certain topologically or functionally unique units-embedded carbon nanorings have sprung up in the past decade. Herein, we report the facile and efficient synthesis of three cyclooctatetraene-embedded carbon nanorings (COTCNRs) that contain three (COTCNR1 and COTCNR2) and four (COTCNR3) COT units in a one-pot Yamamoto coupling. These nanorings feature hoop-shaped segments of Gyroid (G-), Diamond (D-), and Primitive (P-) type carbon schwarzites. The conformations of the trimeric nanorings COTCNR1 and COTCNR2 are shape-persistent, whereas the tetrameric COTCNR3 possesses a flexible carbon skeleton which undergoes conformational changes upon forming host-guest complexes with fullerenes (C60 and C70), whose co-crystals may potentially serve as fullerene-based semiconducting supramolecular wires with electrical conductivities on the order of 10-7 S cm-1 (for C60⊂COTCNR3) and 10-8 S cm-1 (for C70⊂COTCNR3) under ambient conditions. This research not only describes highly efficient one-step syntheses of three cyclooctatetraene-embedded carbon nanorings which feature hoop-shaped segments of distinctive topological carbon schwarzites, but also demonstrates the potential application in electronics of the one-dimensional fullerene arrays secured by COTCNR3.

4.
Angew Chem Int Ed Engl ; 63(13): e202317947, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38298087

RESUMO

Although our knowledge and understanding of adsorptions in natural and artificial systems has increased dramatically during the past century, adsorption associated with nonporous polymers remains something of a mystery, hampering applications. Here we demonstrate a model system for adaptisorption of nonporous polymers, wherein dative B-N bonds and host-guest binding units act as the kinetic and thermodynamic components, respectively. The coupling of these two components enables nonporous polymer crystals to adsorb molecules from solution and undergo recrystallization as thermodynamically favored crystals. Adaptisorption of nonporous polymer crystals not only extends the types of adsorption in which the sorbate molecules are integrated in a precise and orderly manner in the sorbent systems, but also provides a facile and accurate approach to the construction of polymeric materials with precise architectures and integrated functions.

5.
Seizure ; 116: 93-99, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37643945

RESUMO

OBJECTIVES: Variants in NEXMIF had been reported associated with intellectual disability (ID) without epilepsy or developmental epileptic encephalopathy (DEE). It is unkown whether NEXMIF variants are associated with epilepsy without ID. This study aims to explore the phenotypic spectrum of NEXMIF and the genotype-phenotype correlations. MATERIALS AND METHODS: Trio-based whole-exome sequencing was performed in patients with epilepsy. Previously reported NEXMIF variants were systematically reviewed to analyze the genotype-phenotype correlations. RESULTS: Six variants were identified in seven unrelated cases with epilepsy, including two de novo null variants and four hemizygous missense variants. The two de novo variants were absent in all populations of gnomAD and four hemizygous missense variants were absent in male controls of gnomAD. The two patients with de novo null variants exhibited severe developmental epileptic encephalopathy. While, the patients with hemizygous missense variants had mild focal epilepsy with favorable outcome. Analysis of previously reported cases revealed that males with missense variants presented significantly higher percentage of normal intellectual development and later onset age of seizure than those with null variants, indicating a genotype-phenotype correlation. CONCLUSION: This study suggested that NEXMIF variants were potentially associated with pure epilepsy with or without intellectual disability. The spectrum of epileptic phenotypes ranged from the mild epilepsy to severe developmental epileptic encephalopathy, where the epileptic phenotypes variability are potentially associated with patients' gender and variant type.


Assuntos
Epilepsia Generalizada , Epilepsia , Deficiência Intelectual , Humanos , Masculino , Deficiência Intelectual/complicações , Deficiência Intelectual/genética , Epilepsia/complicações , Epilepsia/genética , Convulsões/complicações , Epilepsia Generalizada/complicações , Epilepsia Generalizada/genética , Fenótipo
6.
Molecules ; 28(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38005225

RESUMO

Food that contains lean meat powder (LMP) can cause human health issues, such as nausea, headaches, and even death for consumers. Traditional methods for detecting LMP residues in meat are often time-consuming and complex and lack sensitivity. This article provides a review of the research progress on the use of surface-enhanced Raman spectroscopy (SERS) technology for detecting residues of LMP in meat. The review also discusses several applications of SERS technology for detecting residues of LMP in meat, including the enhanced detection of LMP residues in meat based on single metal nanoparticles, combining metal nanoparticles with adsorbent materials, combining metal nanoparticles with immunizing and other chemicals, and combining the SERS technology with related techniques. As SERS technology continues to develop and improve, it is expected to become an even more widely used and effective tool for detecting residues of LMP in meat.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Humanos , Pós , Análise Espectral Raman/métodos , Carne , Nanopartículas Metálicas/química
7.
Polymers (Basel) ; 15(20)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37896403

RESUMO

Cellulose-based conductive materials (CCMs) have emerged as a promising class of materials with various applications in energy and sensing. This review provides a comprehensive overview of the synthesis methods and properties of CCMs and their applications in batteries, supercapacitors, chemical sensors, biosensors, and mechanical sensors. Derived from renewable resources, cellulose serves as a scaffold for integrating conductive additives such as carbon nanotubes (CNTs), graphene, metal particles, metal-organic frameworks (MOFs), carbides and nitrides of transition metals (MXene), and conductive polymers. This combination results in materials with excellent electrical conductivity while retaining the eco-friendliness and biocompatibility of cellulose. In the field of energy storage, CCMs show great potential for batteries and supercapacitors due to their high surface area, excellent mechanical strength, tunable chemistry, and high porosity. Their flexibility makes them ideal for wearable and flexible electronics, contributing to advances in portable energy storage and electronic integration into various substrates. In addition, CCMs play a key role in sensing applications. Their biocompatibility allows for the development of implantable biosensors and biodegradable environmental sensors to meet the growing demand for health and environmental monitoring. Looking to the future, this review emphasizes the need for scalable synthetic methods, improved mechanical and thermal properties, and exploration of novel cellulose sources and modifications. Continued innovation in CCMs promises to revolutionize sustainable energy storage and sensing technologies, providing environmentally friendly solutions to pressing global challenges.

8.
Chem Sci ; 14(31): 8393-8400, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37564407

RESUMO

In contrast to a plethora of macrocyclic and cage compounds, spirophanes have remained largely unexplored. We report herein the construction, structure and properties of unprecedented tetrahomo corona[4]arene-based ditopic and tritopic macrocycles of spiro structures. Synthesis was conveniently achieved by means of an efficient SNAr reaction from simple and commercially available starting materials. Racemic samples were resolved into enantiopure chiral tetrahomo i-corona[4]arenes, spirophanes and bispirophanes which show interesting chiroptical properties. The acquired electron-deficient macrocyclic compounds were found to adopt unique conformational structures and to form distinct complexes with TTF in the solid state. Our study provides a new opportunity to develop multitopic macrocycles of different topologies which have potential applications in supramolecular chemistry.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123097, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37418907

RESUMO

Clenbuterol is often used as a feed additive to increase the percentage of lean meat in livestock. Meat containing clenbuterol can cause many illnesses and even death for people. In this paper, the particle growth method was used to prepare gold colloids of different sizes, and the enhanced effectiveness of gold colloids of different sizes on clenbuterol in pork was investigated. The results showed that the gold colloid with the best enhanced effectiveness for clenbuterol had a particle size of approximately 90 nm. Second, a sample collection component was designed to detect clenbuterol from bottom to top, solving the problem of poor reproducibility of Surface-enhanced Raman scattering (SERS) detection caused by different droplet sizes and shapes. Then, the influence of different volumes of samples and concentrations of aggregating compounds on the enhanced effectiveness was optimized. The results showed that, based on the sample collection components designed in this article, 5 µL of enhanced substrate, 7.5 µL of clenbuterol and 3 µL of 1 mol/L mixed detection of NaCl solution had the best enhanced performance. Finally, 88 pork samples (0.5, 1, 1.5,…, 10, 12, 14 µg/g) with different concentrations were divided into correction sets and prediction sets in a ratio of 3:1. Unary linear regression models were established between the concentration of clenbuterol residue in the pork and the intensity of the bands at 390, 648, 1259, 1472, and 1601 cm-1. The results showed that the unary linear regression models at 390, 648, and 1259 cm-1 had lower root mean square errors than those at 1472 and 1601 cm-1. The intensity of the three bands and the concentration of clenbuterol residue in the pork were selected to establish a multiple linear regression model, and the concentration of clenbuterol residue in the pork was predicted. The results showed that the determination coefficients (R2) of the correction set and the prediction set were 0.99 and 0.99, respectively. The root mean square errors (RMSE) of the correction set and the prediction set were 0.169 and 0.184, respectively. The detection limit of clenbuterol in pork by this method is 42 ng/g, which can realize the crude screening of pork containing clenbuterol in the market.


Assuntos
Clembuterol , Carne de Porco , Carne Vermelha , Animais , Suínos , Humanos , Coloide de Ouro , Carne Vermelha/análise , Reprodutibilidade dos Testes , Tamanho da Partícula , Ouro/química , Coloides
10.
J Am Chem Soc ; 145(24): 13223-13231, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37294599

RESUMO

Single-crystal-to-single-crystal (SCSC) polymerization offers an effective protocol for the environmentally friendly preparation of polymer single crystals (PSCs) with extremely high crystallinity and very large molecular weights. Single-crystal X-ray diffraction (SCXRD) serves as a powerful technique for the in-depth characterization of their structures at a molecular level. Hence, a fundamental understanding of the structure-property relationships of PSCs is within our reach. Most of the reported PSCs, however, suffer from poor solubility, a property which hampers their post-functionalization and solution processability when it comes to practical applications. Here, we report soluble and processable PSCs with rigid polycationic backbones by taking advantage of an ultraviolet-induced topochemical polymerization from an elaborately designed monomer that results in a multitude of photoinduced [2 + 2] cycloadditions. The high crystallinity and excellent solubility of the resulting polymeric crystals enable their characterization both in the solid state by X-ray crystallography and electron microscopy and in the solution phase by NMR spectroscopy. The topochemical polymerization follows first-order reaction kinetics to a first approximation. Post-functionalization of the PSCs by anion exchange renders them super-hydrophobic materials for water purification. Solution processability endows PSCs with excellent gel-like rheological properties. This research represents a major step towards the controlled synthesis and full characterization of soluble single-crystalline polymers, which may find application in the fabrication of PSCs with many different functions.

11.
J Am Chem Soc ; 145(16): 9118-9128, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37015020

RESUMO

The novel selenoviologen-based tetracationic cyclophanes (green boxes 3 and 5) with rigid electron-deficient cavities are synthesized via SN2 reactions in two steps. The green boxes exhibit good redox properties, narrow energy gaps, and strong absorption in the visible range (370-470 nm), especially for the green box 5 containing two selenoviologen (SeV2+) units. Meanwhile, the femtosecond transient absorption (fs-TA) reveals that the green boxes have a stabilized dicationic biradical, high efficiency of intramolecular charge transfer (ICT), and long-lived charge separation state due to the formation of cyclophane structure. Based on the excellent photophysical and redox properties, the green boxes are applied to electrochromic devices (ECDs) and visible-light-driven hydrogen production with a high H2 generation rate (34 µmol/h), turnover number (203), and apparent quantum yield (5.33 × 10-2). In addition, the host-guest recognitions are demonstrated between the green boxes and electron-rich guests (e.g., G1:1-naphthol and G2:platinum(II)-tethered naphthalene) in MeCN through C-H···π and π···π interactions. As a one-component system, the host-guest complexes of green box⊃G2 are successfully applied to visible-light photocatalytic hydrogen production due to the intramolecular electron transfer (IET) between platinum(II) of G2 and SeV2+ of the green box, which provides a simplified system for solar energy conversion.

12.
Eur J Med Chem ; 255: 115391, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37099836

RESUMO

As a popular healthy tea beverage, Jinsi Huangju has been consumed in China for hundreds of years. However, its active ingredients which dissolved in hot water have not been fully determined. In this study, 14 compounds were identified by different spectroscopic techniques, including 11 compounds identified in this plant for the first time. For in-depth studies, apigenin-7-O-6″-malonylglucoside (8) and luteolin-7-O-6″-malonylglucoside (9) were synthesized for the first time by 5 steps in 1.2% overall yields. Further analyses of the natural compounds showed that 8 could inhibit pancreatic lipase, reduce cellular lipid contents, and attenuate insulin resistance in vitro. Furthermore, 8 restore lipid and inflammatory profiles in the plasma and liver (TG, TC, ALT, AST, LDL-C, HDL-C, MPO, and IL-6) and attenuated hepatic steatosis in NAFLD mouse models. In conclusion, Jinsi Huangju and its active ingredients are candidates for developing drug, functional foods and therapeutic strategies for hyperlipidaemia and NAFLD.


Assuntos
Chrysanthemum , Hiperlipidemias , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Chrysanthemum/química , Hiperlipidemias/tratamento farmacológico , Lipídeos/farmacologia , Fígado , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico
13.
J Clin Hypertens (Greenwich) ; 25(5): 440-452, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37120711

RESUMO

This retrospective study compared cardiovascular (CV) outcomes between initial ß-blocker (BB) + calcium channel blocker (CCB) dual therapy ("B + C") and other initial dual therapies in Chinese newly diagnosed hypertensive patients. In this study, all patients in a regional electronic database with newly diagnosed hypertension from January 01, 2012 to December 31, 2016 who received any initial optimal dual therapy recommended by the Chinese hypertension guideline were included. 1:2 propensity score matching (PSM) was used to balance baseline characteristics between patients receiving B + C and patients receiving other initial dual therapies ("Others"). The primary outcome was major adverse cardiovascular events (MACE) that occurred from January 01, 2012 to December 31, 2017, consisting of non-fatal stroke, non-fatal myocardial infarction (MI), non-fatal chronic heart failure (CHF), and all-cause death. Cox proportional hazard models were used to compare these CV outcomes in the 2 matched cohorts. After the PSM, 6227 patients receiving B + C and 12 454 patients receiving Others were included. Compared to patients receiving Others, patients receiving B + C had a significantly lower risk of MACE (hazard ratio [HR] 0.85; 95% confidential interval [CI] 0.78-0.92; p < .001), non-fatal stroke (HR 0.89; 95% CI 0.81-0.98; p = .018) and non-fatal CHF (HR 0.74; 95% CI 0.63-0.86; p < .0001). Additionally, differences in risks of non-fatal MI and all-cause death between the 2 treatment cohorts were not statistically significant. In conclusion, BB + CCB initial dual therapy was associated with a lower risk of MACE, stroke, and CHF than other optimal initial dual therapies recommended by the Chinese hypertension guideline in Chinese newly diagnosed hypertensive patients.


Assuntos
Antagonistas Adrenérgicos beta , Bloqueadores dos Canais de Cálcio , Hipertensão , Humanos , Antagonistas Adrenérgicos beta/administração & dosagem , Antagonistas Adrenérgicos beta/uso terapêutico , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/uso terapêutico , População do Leste Asiático , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/prevenção & controle , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/prevenção & controle , Estudos Retrospectivos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle
14.
Nature ; 613(7943): 280-286, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36631649

RESUMO

Macroscopic electric motors continue to have a large impact on almost every aspect of modern society. Consequently, the effort towards developing molecular motors1-3 that can be driven by electricity could not be more timely. Here we describe an electric molecular motor based on a [3]catenane4,5, in which two cyclobis(paraquat-p-phenylene)6 (CBPQT4+) rings are powered by electricity in solution to circumrotate unidirectionally around a 50-membered loop. The constitution of the loop ensures that both rings undergo highly (85%) unidirectional movement under the guidance of a flashing energy ratchet7,8, whereas the interactions between the two rings give rise to a two-dimensional potential energy surface (PES) similar to that shown by FOF1 ATP synthase9. The unidirectionality is powered by an oscillating10 voltage11,12 or external modulation of the redox potential13. Initially, we focused our attention on the homologous [2]catenane, only to find that the kinetic asymmetry was insufficient to support unidirectional movement of the sole ring. Accordingly, we incorporated a second CBPQT4+ ring to provide further symmetry breaking by interactions between the two mobile rings. This demonstration of electrically driven continual circumrotatory motion of two rings around a loop in a [3]catenane is free from the production of waste products and represents an important step towards surface-bound14 electric molecular motors.

15.
Biosensors (Basel) ; 12(11)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36354507

RESUMO

Fresh pork is prone to spoilage during storage, transportation, and sale, resulting in reduced freshness. The total viable count (TVC) and total volatile basic nitrogen (TVB-N) content are key indicators for evaluating the freshness of fresh pork, and when they reach unacceptable limits, this seriously threatens dietary safety. To realize the on-site, low-cost, rapid, and non-destructive testing and evaluation of fresh pork freshness, a miniaturized detector was developed based on a cost-effective multi-channel spectral sensor. The partial least squares discriminant analysis (PLS-DA) model was used to distinguish fresh meat from deteriorated meat. The detector consists of microcontroller, light source, multi-channel spectral sensor, heat-dissipation modules, display system, and battery. In this study, the multispectral data of pork samples with different freshness levels were collected by the developed detector, and its ability to distinguish pork freshness was based on different spectral shape features (SSF) (spectral ratio (SR), spectral difference (SD), and normalized spectral intensity difference (NSID)) were compared. The experimental results show that compared with the original multispectral modeling, the performance of the model based on spectral shape features is significantly improved. The model established by optimizing the spectral shape feature variables has the best performance, and the discrimination accuracy of its prediction set is 91.67%. In addition, the validation accuracy of the optimal model was 86.67%, and its sensitivity and variability were 87.50% and 85.71%, respectively. The results show that the detector developed in this study is cost-effective, compact in its structure, stable in its performance, and suitable for the on-site digital rapid non-destructive testing of freshness during the storage, transportation, and sale of fresh pork.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Suínos , Carne Vermelha/análise , Análise dos Mínimos Quadrados , Carne , Nitrogênio/análise
16.
Biosensors (Basel) ; 12(10)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36290996

RESUMO

Clenbuterol (CB) is a synthetic ß-receptor agonist which can be used to improve carcass leanness in swine, but its residues in pork also pose health risks. In this report, surface-enhanced Raman scattering (SERS) technology was used to achieve rapid detection and identification of clenbuterol hydrochloride (CB) residues. First, the effects of several different organic solvents on the extraction efficiency were compared, and it was found that clenbuterol in pork had a better enhancement effect using ethyl acetate as an extraction agent. Then, SERS signals of clenbuterol in different solvents were compared, and it was found that clenbuterol had a better enhancement effect in an aqueous solution. Therefore, water was chosen as the solvent for clenbuterol detection. Next, enhancement effect was compared using different concentration of sodium chloride solution as the aggregating compound. Finally, pork samples with different clenbuterol content (1, 3, 5, 7, 9, and 10 µg/g) were prepared for quantitative analysis. The SERS spectra of samples were collected with 0.5 mol/L of NaCl solution as aggregating compound and gold colloid as an enhanced substrate. Multiple scattering correction (MSC) and automatic Whittaker filter (AWF) were used for preprocessing, and the fluorescence background contained in the original Raman spectra was removed. A unary linear regression model was established between SERS intensity at 1472 cm-1 and clenbuterol content in pork samples. The model had a better linear relationship with a correlation coefficient R2 of 0.99 and a root mean square error of 0.263 µg/g. This method can be used for rapid screening of pork containing clenbuterol in the market.


Assuntos
Clembuterol , Carne de Porco , Carne Vermelha , Suínos , Animais , Clembuterol/análise , Análise Espectral Raman/métodos , Cloreto de Sódio , Ouro/química , Carne Vermelha/análise , Coloide de Ouro , Água , Solventes/análise
17.
Heliyon ; 8(6): e09576, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35928435

RESUMO

Salbutamol is a ß-adrenergic receptor agonist compound which has been abused as an animal growth promoter to improve carcass lean meat percentage. At present, the detection of salbutamol by SERS mostly uses gold colloid as substrate, which is expensive and has a high detection limit. In this report, Raman enhancement signal of salbutamol was compared with concentrated gold and silver colloids. The results show that the concentrated silver colloid prepared by reducing silver nitrate with hydroxylamine hydrochloride had superior performance. Three silver colloids with different particle sizes were synthesized by the same reducing agent and used as substrates for spectra acquisition of salbutamol to explore the enhancement performance of different silver nanoparticles sizes on salbutamol. The results showed that silver nanoparticles with larger particle sizes were more conducive to the adsorption of salbutamol. Finally, under the optimal conditions (Silver colloid A as enhanced substrate, 0.2 mol/L NaOH aqueous solution as aggregating compound), a better linear relationship between the concentration of salbutamol (ranged from 0.2 to 1 mg/L) and SERS intensity. The linear equation between SERS intensity and salbutamol concentration was C = 0.0023∙I-0.079 (mg/L) with a good linearity (R 2 =0.994) and lower root mean square error (RMSE c = 0.022 mg/L), where C (mg/L) was the concentration of salbutamol solution and I was the SERS intensity of salbutamol solution. Validation set correlation coefficient was 0.988 and prediction root mean square error was 0.029 mg/L. This method provides a new idea for further reducing the detection limit of salbutamol. This study is helpful to further develop a simple and low-cost SERS detection method of salbutamol based on silver colloid.

18.
Food Chem ; 396: 133673, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35849984

RESUMO

This study aimed to develop a cost-effective fluorescence imaging system to rapidly monitor pork freshness indicators during chilled storage. The system acquired fluorescence images of pork and the color features were extracted from these images to establish partial least squares regression (PLSR) models to predict total volatile basic nitrogen (TVB-N), total viable count (TVC), pH for pork. For TVB-N, TVC and pH values, Rp were 0.92, 0.88 and 0.74, residual predictive deviation (RPD) were 2.24, 2.03, and 1.19, respectively. For TVB-N and TVC indicators showed that the predictive ability of this model was largely comparable to that of fluorescence hyperspectral imaging. However, combining fluorescence and color imaging improved the model's predictive ability. For TVB-N, TVC and pH, Rp were 0.94, 0.93 and 0.85, RPD were 2.62, 2.59, and 1.95, respectively. Therefore, this study developed a system with great potential for detecting the value of most pork quality indicators in real-time.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Análise dos Mínimos Quadrados , Nitrogênio , Imagem Óptica , Carne Vermelha/análise , Suínos
19.
Front Mol Neurosci ; 15: 825390, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35663266

RESUMO

Objective: The LAMA5 gene encodes the laminin subunit α5, the most abundant laminin α subunit in the human brain. It forms heterotrimers with the subunit ß1/ß2 and γ1/γ3 and regulates neurodevelopmental processes. Genes encoding subunits of the laminin heterotrimers containing subunit α5 have been reported to be associated with human diseases. Among LAMAs encoding the laminin α subunit, LAMA1-4 have also been reported to be associated with human disease. In this study, we investigated the association between LAMA5 and epilepsy. Methods: Trios-based whole-exome sequencing was performed in a cohort of 118 infants suffering from focal seizures with or without spasms. Protein modeling was used to assess the damaging effects of variations. The LAMAs expression was analyzed with data from the GTEX and VarCards databases. Results: Six pairs of compound heterozygous missense variants in LAMA5 were identified in six unrelated patients. All affected individuals suffered from focal seizures with mild developmental delay, and three patients presented also spasms. These variants had no or low allele frequencies in controls and presented statistically higher frequency in the case cohort than in controls. The recessive burden analysis showed that recessive LAMA5 variants identified in this cohort were significantly more than the expected number in the East Asian population. Protein modeling showed that at least one variant in each pair of biallelic variants affected hydrogen bonds with surrounding amino acids. Among the biallelic variants in cases with only focal seizures, two variants of each pair were located in different structural domains or domains/links, whereas in the cases with spasms, the biallelic variants were constituted by two variants in the identical functional domains or both with hydrogen bond changes. Conclusion: Recessive LAMA5 variants were potentially associated with infant epilepsy. The establishment of the association between LAMA5 and epilepsy will facilitate the genetic diagnosis and management in patients with infant epilepsy.

20.
Chem Sci ; 13(21): 6254-6261, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35733889

RESUMO

Here, we announce the establishment of a new family of organic molecular cages, named cagearenes, by taking advantage of a versatile strategy. These cagearenes were prepared via the Friedel-Crafts reaction by condensing two equivalents of a precursor bearing three 1,4-dimethoxybenzene groups and three equivalents of formaldehyde. Two cages, namely cagearene-1 and cagearene-2, are obtained and well characterized. The cagearene-1 solid exhibits the ability to adsorb benzene vapour from an equimolar benzene/cyclohexane mixture with a purity of 91.1%. Then, the adsorbed benzene molecules can be released from the cage at a relatively lower temperature, namely 70 °C, as a consequence of which, cyclohexane with a high purity was left within the cage solid. Heating the cage solid further at 130 °C led to the production of cyclohexane with a purity up to 98.7%. As inferred from the single crystal structures and theoretical calculations, the ability of the cage in programmed release of benzene and cyclohexane results from the different binding modes of these two guests.

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