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1.
Sci China Chem ; : 1-17, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35035391

RESUMO

Cost-effective, rapid, and accurate virus detection technologies play key roles in reducing viral transmission. Prompt and accurate virus detection enables timely treatment and effective quarantine of virus carrier, and therefore effectively reduces the possibility of large-scale spread. However, conventional virus detection techniques often suffer from slow response, high cost or sophisticated procedures. Recently, two-dimensional (2D) materials have been used as promising sensing platforms for the high-performance detection of a variety of chemical and biological substances. The unique properties of 2D materials, such as large specific area, active surface interaction with biomolecules and facile surface functionalization, provide advantages in developing novel virus detection technologies with fast response and high sensitivity. Furthermore, 2D materials possess versatile and tunable electronic, electrochemical and optical properties, making them ideal platforms to demonstrate conceptual sensing techniques and explore complex sensing mechanisms in next-generation biosensors. In this review, we first briefly summarize the virus detection techniques with an emphasis on the current efforts in fighting again COVID-19. Then, we introduce the preparation methods and properties of 2D materials utilized in biosensors, including graphene, transition metal dichalcogenides (TMDs) and other 2D materials. Furthermore, we discuss the working principles of various virus detection technologies based on emerging 2D materials, such as field-effect transistor-based virus detection, electrochemical virus detection, optical virus detection and other virus detection techniques. Then, we elaborate on the essential works in 2D material-based high-performance virus detection. Finally, our perspective on the challenges and future research direction in this field is discussed.

2.
Mol Pharm ; 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982563

RESUMO

Medullary thyroid carcinoma (MTC) is a malignant neuroendocrine tumor with a high recurrence rate. Amyloid plaques formed from the misfolding of calcitonin are the key characteristics of MTC. Herein, we conducted a first-in-human pilot clinical study by applying a ß-amyloid-specific radiotracer, [18F]AV-45, to positron emission tomography (PET)/computed tomography (CT) imaging of MTC. The presence of amyloid plaques in the tumor tissue sections from five MTC patients was confirmed by hematoxylin and eosin (H&E) and Congo Red staining. [18F]AV-45 selectively accumulated in the amyloid plaques in the continued tumor tissue sections with similar distribution patterns to the H&E and Congo Red staining. In addition, the [18F]AV-45 uptake can be largely blocked by its nonradioactive reference compound. The [18F]AV-45 accumulation in the thyroid, neck lymph nodes, and muscles in healthy human subjects is close to the background indicated by PET/CT imaging. In the comparison PET/CT imaging study of a recurrent MTC patient, 2-deoxy-2-[18F]fluoro-d-glucose ([18F]FDG) showed an elevated uptake by multiple neck lymph nodes. In contrast, only one of these neck lymph nodes had increased [18F]AV-45 uptake. Postoperative histopathological analysis confirmed the [18F]AV-45 PET-positive lymph node as MTC with amyloid deposition, while other [18F]FDG positive lymph nodes were free from MTC and amyloid plaques. Thus, [18F]AV-45 showed the promise for the clinical PET/CT imaging of MTC.

3.
J Hazard Mater ; 427: 128210, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34999401

RESUMO

Polyvinyl chloride (PVC) is one of the most commonly used plastics. The treatment and recycling of PVC waste is still challenging, due to its non-biodegradability, low thermal stability, high Cl content and low product value. In this study, a one-pot method was developed to upcycle PVC into valuable carbon materials, pipeline-quality pyrolysis gas and chlorides. The well-designed process included dechlorination by Cl-fixative (ZnO or KOH), carbonization of dechlorinated polyenes, and modification of carbon materials in sequence. ZnO and KOH converted 84.48% and 94.15% of total Cl into corresponding chlorides, respectively. CH4 and H2 accounted for 81.87-99.34 vol% of pyrolysis gas with higher heat values of 30.11-32.84 MJ m-3, which can be used as substitute natural gas. As high as 83.13% of the C element was converted into carbon materials. The morphology, structure and property of carbon materials can be modified by different Cl-fixatives. Millimeter-scale carbon spheres with mono-dispersity and porous carbon with a high specific surface area of 1922 m2 g-1 were obtained when ZnO and KOH were added, respectively. Moreover, the reaction mechanisms of PVC with Cl-fixatives were also deciphered through thermogravimetric analysis and thermodynamic simulation.

4.
Environ Res ; 208: 112703, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35016862

RESUMO

Neonicotinoid insecticides (NEOs) are commonly applied for pest control in China and around the world. Previous studies reported that NEOs are hepatotoxic to mammals. However, limited studies have explored the associations between NEOs exposure and liver disease. In the present study, we detected six parent NEOs (p-NEOs), including acetamiprid, thiacloprid, dinotefuran, clothianidin, imidacloprid, and thiamethoxam, and five characteristic metabolites (m-NEOs), including 5-hydroxy-imidacloprid, olefin-imidacloprid, N-desmethyl-acetamiprid, 1-methyl-3-(tetrahydro-3-furylmethyl) guanidine and 1-methyl-3-(tetrahydro-3-furyl methyl) urea, in blood samples collected from healthy donors (n = 100; females vs. males: 45 vs. 55; age: 22-91 years) and liver cancer patients (n = 274; females vs. males: 118 vs. 156; age: 11-88 years) in one hospital from Guangzhou city, South China. NEOs were frequently detected (61%-94%) in blood samples, with median concentrations ranging from 0.19 ng/mL to 1.28 ng/mL and 0.20 ng/mL to 2.03 ng/mL for healthy and liver cancer populations, respectively. olefin-imidacloprid was the most abundant NEOs in healthy and liver cancer populations, accounting for 23.4% and 20.7%, respectively. Significant positive correlations among most m-NEOs concentrations were found, and associations between m-NEOs and their corresponding p-NEOs were positively correlated. These findings indicated that the sources of m-NEOs were both endogenous and exogeneous. Females had higher median concentrations of NEOs and their metabolites than males. Moreover, the α-fetoprotein values and blood concentrations of target analytes (r = 0.428-0.601, p < 0.05) were positively correlated. Meanwhile, associations between the concentrations of p-NEOs and m-NEOs and liver cancer were found (odds ratio = 2.33-9.02, 95% confidence interval = 0.31-22.7, p < 0.05), indicating that human exposure to NEOs and their metabolites might increase the odds of liver cancer prevalence. Our work provided a new insight into the hepatotoxicity of NEOs and their metabolites, and human health risks of exposure to these pollutants warranted further studies.

5.
Fitoterapia ; : 105124, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35007685

RESUMO

Four new cytochalasans, arbuschalasins A-D (1-4), along with thirteen known analogues (5-17), were isolated from the solid rice medium of endophytic fungus Xylaria arbuscula. Arbuschalasins A-B feature a rare 5/6/6/6 fused ring system while arbuschalasin D was characterized as the first example of natural cytochalasans that possesses a 5/5/11 fused scaffold. The structures of 1-4 were assigned by spectroscopic data, with their absolute structures being determined by electronic circular dichroism (ECD) calculations. All of the isolates were evaluated against the human colorectal adenocarcinoma cell lines (HCT15). Compounds 6 and 7 showed significant inhibitory effects (IC50 values were 13.5 and 13.4 µM, respectively), being more active than those of the positive control, fluorouracil (103.1 µM).

6.
Chin J Integr Med ; 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35023061

RESUMO

OBJECTIVES: To summarize the measures and rules of Chinese medicine (CM) and provide reference for clinical application in the prevention and treatment of coronavirus disease (COVID-19). METHODS: The data source was from CM COVID-19 prevention and treatment programs on government websites and official media websites of the different provinces and cities. The search lasted from December 8, 2019 to March 10, 2020. Main variables were medication frequency and combinations of medicines. Cluster analysis and complex network analysis were used by prevention and treatment stage and by area. RESULTS: Among 27 CM diagnosis and treatment plans, 203 therapeutic prescriptions were enrolled, of which the top 4 herbs were: Radix glycyrrhizae, Semen armeniacae amarum, Herba ephedrae, and Herba agastachis, respectively. The core combinations were Herba ephedrae and Semen armeniacae amarum. Forty-eight preventive formulae were identified. Ten herbs, including Radix Astragali seu hedysari, Radix glycyrrhizae, Radix saposhnikoviae, Flos lonicerae, etc. were most frequently used. The core prescription of CM compatibility was Radix astragali seu hedysari, Radix glycyrrhizae, and Radix saposhnikoviae, which is the main component of Yu Ping Feng San. There were 45 prevention and treatment prescriptions in East China; the most used CM was Radix glycyrrhizae, Herba agastachis, Pericarpium citri reticulatae, and Gypsum fibrosum. Fifty prescriptions were identified in North China. According to CM analyses, Herba agastachis, Semen armeniacae amarum, Herba ephedrae, and Poria were most frequently used. CONCLUSIONS: CM for COVID-19 prevention mainly focuses on improving human immunity; for treatment, prescription focuses on clearing the lungs and removing dampness. Prescriptions vary with regions, perhaps due to climatic and environmental differences, which help clinicians to quickly make CM plans and treat patients according to clinical status, further minimizing resource wastage.

8.
Chem Commun (Camb) ; 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35024703

RESUMO

The C-N borylation of arylhydrazine hydrochlorides with bis(pinacolato)diboron was achieved under photochemical and electrochemical conditions, respectively. This novel and scalable transformation provides two efficient and mild transition-metal-free synthetic routes towards aryl boronate esters from easily available arylhydrazines.

9.
Carbohydr Polym ; 278: 118910, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34973731

RESUMO

Staphylococcus aureus (S. aureus) is the major pathogen responsible for mastitis in dairy cows, an important threat to their health, but prevention of S. aureus infection of the mammary gland remains challenging. Berberine hydrochloride (BH), a naturally occurring phytochemical, exhibits a wide range of activities, including antibacterial effects on S. aureus. In this study, we prepared a novel berberine hydrochloride-carboxymethyl chitosan hydrogel (BH-CMCH) with excellent thermosensitivity, injectability and in vitro antibacterial activity. In a rat model of mastitis induced by S. aureus, mammary duct injection of BH-CMCH reduced the bacterial load in infected mammary gland tissue and protected the tissue from damage from infection. In addition, proteomics analysis showed that mammary duct injection of BH-CMCH enhanced autolysosome degradation and promoted the innate immune response by activating the lysosomal pathway and up-regulating related significantly differentially expressed proteins (SDEPs). Taken together, the findings support the potential of BH-CMCH as an antibacterial agent against S. aureus-induced mastitis.

10.
J Am Chem Soc ; 144(1): 547-555, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34932339

RESUMO

Controlled construction of bimetallic nanostructures with a well-defined heterophase is of great significance for developing highly efficient nanocatalysts and investigating the structure-dependent catalytic performance. Here, a wet-chemical synthesis method is used to prepare Au@Pd core-shell nanorods with a unique fcc-2H-fcc heterophase (fcc: face-centered cubic; 2H: hexagonal close-packed with a stacking sequence of "AB"). The obtained fcc-2H-fcc heterophase Au@Pd core-shell nanorods exhibit superior electrocatalytic ethanol oxidation performance with a mass activity as high as 6.82 A mgPd-1, which is 2.44, 6.96, and 6.43 times those of 2H-Pd nanoparticles, fcc-Pd nanoparticles, and commercial Pd/C, respectively. The operando infrared reflection absorption spectroscopy reveals a C2 pathway with fast reaction kinetics for the ethanol oxidation on the prepared heterophase Au@Pd nanorods. Our experimental results together with density functional theory calculations indicate that the enhanced performance of heterophase Au@Pd nanorods can be attributed to the unconventional 2H phase, the 2H/fcc phase boundary, and the lattice expansion of the Pd shell. Moreover, the heterophase Au@Pd nanorods can also serve as an efficient catalyst for the electrochemical oxidation of methanol, ethylene glycol, and glycerol. Our work in the area of phase engineering of nanomaterials (PENs) opens the way for developing high-performance electrocatalysts toward future practical applications.

11.
Food Chem ; 366: 130614, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34304137

RESUMO

Understanding how starch constituent in frozen dough affected bread quality would be valuable for contributing to the frozen products with better quality. To elucidate the underlying mechanism, starch was fractionated from multiple freezing-thawing (F/T) treated dough and reconstituted with gluten. Results showed that F/T treatment destructed the molecular and supramolecular structures of starch, which were more severe as the F/T cycle increasing. These structural disorganizations made water molecules easier to permeate into the interior of starch granules and form hydrogen bonds with starch molecular chains, which elevated the peak, breakdown, setback and final viscosity of starch paste. In addition, F/T treatment resulted in decreased specific volume (from 1.54 to 0.90 × 103 m3/Kg) and increased hardness (from 42.98 to 52.31 N) for steamed bread. We propose the strengthened water absorption ability and accelerated intra- and inter-molecular rearrangement of starch molecules and weak stability of "starch-gluten matrices" would allow interpreting deteriorated bread quality.


Assuntos
Pão , Amido , Pão/análise , Farinha/análise , Congelamento , Glutens , Vapor
12.
Environ Res ; 203: 111772, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34324851

RESUMO

Neonicotinoids (NEOs) are extensively applied in global agricultural production for pest control but have adverse effects on human health. In this study, the concentrations of six NEOs and three characteristic metabolites were investigated by collecting 200 serum samples from an elderly population in China. Results showed that the NEOs and their metabolites were widely detected (89%-98 %) in the serum samples from the osteoporosis (OP) (n = 120) and non-OP (n = 80) population, and their median concentrations ranged from 0.04 ng/mL to 5.99 ng/mL and 0.01 ng/mL to 2.02 ng/mL, respectively. N-desmethyl-acetamiprid (ACE-dm) was the most abundant NEOs in the serum samples. Gender-related differences were found in concentrations of most NEOs and their metabolites in serum, with males having higher target analytes than females. Significantly (p < 0.05) positive correlations were observed among most NEO concentrations, suggesting that exposure source of these substances is common or related. However, associations between the concentrations of characteristic metabolites and their corresponding NEOs were insignificant, probably because the exogenous intake are the primary sources of metabolites of NEOs instead of the internal biotransformation. The associations between NEO concentrations (i.e., ACE-dm, dinotefuran, and olefin-imidacloprid) and OP (OR = 2.33-6.92, 95 % CI = 0.37-16.9, p-trend < 0.05) indicate that NEO exposure is correlated with increased odds of prevalent OP. This study is the first to document the profiles of NEOs and their metabolites in serum samples collected from an elderly population in South China and examine the relationships between NEO exposure and OP.


Assuntos
Inseticidas , Osteoporose , Idoso , China , Coleta de Dados , Feminino , Humanos , Inseticidas/análise , Masculino , Neonicotinoides , Osteoporose/epidemiologia
13.
J Hazard Mater ; 423(Pt A): 126991, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34482081

RESUMO

Periodate (PI)-based advanced oxidation processes have recently received increasing attentions. Herein, PI was readily activated by nano zero-valent iron (nZVI) and subsequently led to the enhanced oxidation of organic contaminants, with the removal performance of sulfadiazine (SDZ) in the nZVI/PI process even higher than that in the nZVI/peroxydisulfate process under identical conditions. Kinetic experiments indicated that the decay of SDZ was susceptible to the dosage of nZVI and PI, but was barely affected by pH values (4.0-7.0) under buffered conditions, suggesting the promising performance of the nZVI/PI process in a relatively wide pH range. Selective degradation of contaminants and 18O-isotope labeling assays collectively demonstrated that iodate radical (•IO3), high-valent iron-oxo species (Fe(IV)) and hydroxyl radical (•OH) were responsible for the abatement of organic contaminants. More importantly, due to the relatively weak steric hindrance effect of PI, PI easily adsorbed on the surface of nZVI and no iron leaching was detected throughout the reaction, implying that PI activation induced by nZVI was a surface-mediated process. Besides, PI was not transformed into harmful reactive iodine species. This study proposed an environmental-friendly approach for PI activation and shed new lights on the PI-based processes.


Assuntos
Ferro , Poluentes Químicos da Água , Oxirredução , Ácido Periódico , Poluentes Químicos da Água/análise
14.
J Hazard Mater ; 423(Pt B): 127144, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34555763

RESUMO

During coronavirus disease 2019 pandemic, the exponential increase in clinical waste (CW) generation has caused immense burden to CW treatment facilities. Co-incineration of CW in municipal solid waste incinerator (MSWI) is an emergency treatment method. A material flow model was developed to estimate the change in feedstock characteristics and resulting acid gas emission under different CW co-incineration ratios. The ash contents and lower heating values of the feedstocks, as well as HCl concentrations in flue gas showed an upward trend. Subsequently, 72 incineration residue samples were collected from a MSWI performing co-incineration (CW ratio <10 wt%) in Wuhan city, China, followed by 20 incineration residues samples from waste that were not co-incineration. The results showed that the contents of major elements and non-volatile heavy metals in the air pollution control residues increased during co-incineration but were within the reported ranges, whereas those in the bottom ashes revealed no significant changes. The impact of CW co-incineration at a ratio <10 wt% on the distribution of elements in the incineration residues was not significant. However, increase in alkali metals and HCl in flue gas may cause potential boiler corrosion. These results provide valuable insights into pollution control in MSWI during pandemic.


Assuntos
COVID-19 , Metais Pesados , Eliminação de Resíduos , Cinza de Carvão , Humanos , Incineração , Pandemias , SARS-CoV-2 , Resíduos Sólidos/análise
15.
Bioresour Technol ; 343: 126079, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34610428

RESUMO

Degradation of bioplastics in food-waste-treating anaerobic digestion (AD) plants is becoming an increasingly concerning issue as they are inevitably mixed with food waste during the waste collection process. The aim of this study was to assess the degradation of PBAT/PLA based biopolymer bags during mesophilic and thermophilic AD, co-digested with food waste, and subsequent aerobic post-treatment. After the AD process, no discernable biological degradation was observed for all of the PBAT/PLA polymers. The comparison of FTIR, XRD, TG analysis and contact angle analysis between raw and degraded PBAT/PLA polymer revealed structural changes after anaerobic incubation. Subsequent aerobic treatment facilitated the degradation of the PBAT/PLA polymers from thermophilic AD, which was attributed to the polymer-degrading microorganisms Brevundimonas and Sphingobacterium. Physical disintegration of the PBAT/PLA polymer was observed under thermophilic conditions. Those undegraded polymer fragments could affect digestate quality and increase the risk of releasing microplastics into the environment.


Assuntos
Micobioma , Eliminação de Resíduos , Anaerobiose , Reatores Biológicos , Digestão , Alimentos , Metano , Plásticos , Polímeros , Esgotos
16.
Chemosphere ; 287(Pt 1): 132047, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34474388

RESUMO

Compared with generally reported Mo4+/Mo6+ redox cycle, the exposed Mo2+ active sites of Mo-based materials may have a superior potential to effectively activate PMS. However, Mo2+-involved materials as efficient catalysts in sulfate radical-based advanced oxidation processes (SR-AOPs) has rarely been researched. In this work, a spherical Mo2C-loaded carbon material, Mo2C/C, was prepared for the first time by hydrothermal-calcination method directly used as peroxymonosulfate (PMS) activator towards carbamazepine (CBZ) degradation. The results showed that the Mo2C/C could effectively remove nearly 100% CBZ (5 mg·L-1) in the presence of 0.75 mM PMS within 75 min under the optimal conditions. It was attributed to the reductive Mo2+, as active sites, benefits to absorb PMS on the surface to trigger electron transmission, and the defective carbon structures accelerate the activation of PMS. Consequently, the efficient Mo2+/Mo4+/Mo6+ electron transfer was achieved, resulting in excellent catalysis. A series of reactive species including SO4-, OH and 1O2 species participated in CBZ oxidation degradation. Derived from the superior stability and reusability of Mo2C/C, the removal rate of CBZ still maintained above 80% even after five consecutive cycles, which is expected to be applied in the wastewater treatment including pharmaceuticals in the future.


Assuntos
Peróxidos , Purificação da Água , Carbamazepina , Catálise
17.
Org Lett ; 24(1): 64-68, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-34898225

RESUMO

Unreactive C-N bond activation of anilines was achieved by photoinduced aerobic borylation. A diverse range of tertiary and secondary anilines were converted to aryl boronate esters in moderate to good yields with wide functional group tolerance under simple and ambient photochemical conditions. This transformation achieved the direct and facile C-N bond activation of unreactive anilines, providing a convenient and practical route transforming widely available anilines into useful aryl boronate esters.

19.
Fitoterapia ; 156: 105101, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34921925

RESUMO

Chemical fractionation of the EtOH extract of a medicinal macro fungus, Inonotus obliquus, afforded an array of lanostane-type triterpenoids (1-11) including two new ones (1 and 8). The structures of these compounds were determined on the basis of spectroscopic analyses, single crystal X-ray crystallography of 3-6 and biosynthetic considerations. With the confirmatory structural information provided by X-ray diffraction analysis in hand, several previously reported 21,24-cyclolanostanes, such as inonotsutriols A-C and (20R,21S,24S)-21,24-cyclopenta-3ß,21,25-trihydroxylanosta-8-ene, were structurally corrected. In addition, the NMR data of other types of 21,24-cyclo triterpenoids were also re-examined and structural revisions were thus suggested. Compounds 2, 6 and 8 showed significant cytostatic effects against a panel of tumor cell lines with IC50 values ranging from 7.80 to 18.5 µM. Further assays established that compound 2 exerted promising in vitro anti-breast cancer potential by inhibiting the proliferation and migration of 4T1 cells.

20.
J Hazard Mater ; 424(Pt A): 127249, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34600375

RESUMO

Thermal conversion of solid digestate following anaerobic digestion (AD) can be a solution for producing value-added products and closing the material loop. The products of the novel autogenic pressure carbonization (APC) of food waste and two digestates were characterized to evaluate the temperature effect, product distribution and physicochemical composition. As the temperature increased from 300 to 700 â„ƒ, char yields slightly decreased from 60.0% to 53.3% for the solid digestate from high-solid AD (SDH) while those of the solid digestate from low-solid AD (SDL) varied from 78.7% to 73.2%. X-ray photoelectron spectroscopy (XPS) results indicated that pyridinic N accounts for 40.0% of total N in char of SDL at 700 â„ƒ that can be upgraded to functional N-doped carbon materials. Maximum yield (39.8%) of syngas was obtained at 700 â„ƒ with SDH as a feedstock. After APC at 700 â„ƒ, syngas, mainly consisted of CH4 and CO2, had heating values ranging from 22.4 to 24.6MJm-3, which can be jointly utilized with biogas from AD as fuel. Overall, results from this study demonstrate that APC could be used as a potential thermal conversion process for producing value-added products (N-doped biochar) and biofuel (syngas).


Assuntos
Pirólise , Eliminação de Resíduos , Anaerobiose , Alimentos , Metano , Nitrogênio
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