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1.
Neurochem Res ; 49(5): 1291-1305, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38424396

RESUMO

Parkinson's Disease (PD) is characterized by the loss of dopaminergic neurons, with ferroptosis playing a significant role. Salidroside (SAL) has shown neuroprotective potential, this study aims to explore its capacity to mitigate ferroptosis in PD, focusing on the modulation of the Nuclear Factor E2-Related Factor 2 (Nrf2)/ Glutathione Peroxidase 4 (GPX4) pathway. Male C57BL/6 mice were subjected to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to induce PD-like symptoms, followed by SAL and Nrf2 inhibitor administration. Then behavioral tests, immunohistochemical staining, transmission electron microscopy, and Western blot analysis were conducted to assess motor functions, pathological changes, ferroptosis, and related protein expressions. In vitro, SH-SY5Y cells were treated with erastin to induce ferroptosis to assess the protective effects of SAL. Additionally, A53T-α-synuclein (α-syn) was used to stimulate the PD model, SAL and a Nrf2 inhibitor (ML385) was utilized to elucidate the role of the Nrf2/GPX4 pathway in mitigating ferroptosis in PD. In vivo, SAL significantly improved motor functions and reduced the expression of α-syn, while increasing tyrosine hydroxylase (TH) expression of PD mice. Additionally, SAL treatment notably enhanced the levels of antioxidants and reduced MDA and iron content in the substantia nigra of PD mice. In vitro, SAL treatment increased the TH, GPX4, Nrf2 expression, and mitochondrial membrane potential whereas alleviated ferroptosis through the Nrf2/GPX4 pathway, as evidenced in erastin-induced and α-syn overexpressing SH-SY5Y cells. While these effects were reversed upon Nrf2 inhibition. SAL demonstrates significant potential in mitigating PD pathology and ferroptosis, positioning the Nrf2/GPX4 pathway as a promising therapeutic target. However, future studies should focus on the long-term effects of SAL, its pharmacokinetics, addressing the multifactorial nature of PD pathogenesis.


Assuntos
Ferroptose , Glucosídeos , Neuroblastoma , Doença de Parkinson , Fenóis , Masculino , Humanos , Camundongos , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais , Camundongos Endogâmicos C57BL
2.
Bioresour Technol ; 393: 130027, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37977496

RESUMO

Bioconversion of CO2 to high-valuable products is a globally pursued sustainable technology for carbon neutrality. However, low CO2 activation with formate dehydrogenase (FDH) remains a major challenge for further upcycling due to the poor CO2 affinity, reduction activity and stability of currently used FDHs. Here, we present two recombined mutants, ΔFDHPa48 and ΔFDHPa4814, which exhibit high CO2 reduction activity and antioxidative activity. Compared to FDHPa, the reduction activity of ΔFDHPa48 was increased up to 743 % and the yield in the reduction of CO2 to methanol was increased by 3.16-fold. Molecular dynamics identified that increasing the width of the substrate pocket of ΔFDHPa48 could improve the enzyme reduction activity. Meanwhile, the enhanced rigidity of C-terminal residues effectively protected the active center. These results fundamentally advanced our understanding of the CO2 activation process and efficient FDH for enzymatic CO2 activation and conversion.


Assuntos
Dióxido de Carbono , Formiato Desidrogenases , Dióxido de Carbono/metabolismo , Formiato Desidrogenases/genética , NAD/metabolismo , NADH Desidrogenase , Oxirredução , Formiatos/química
3.
J Am Chem Soc ; 145(51): 28096-28110, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38088827

RESUMO

Bottom-up fabrication protocols for uniform 3D hierarchical structures in solution are rare. We report two different approaches to fabricate uniform 3D spherulites and their precursors using mixtures of poly(ferrocenyldimethylsilane) (PFS) block copolymer (BCP) and PFS homopolymer (HP). Both protocols are designed to promote defects in 2D assemblies that serve as intermediate structures. In a multistep seeded growth protocol, we add the BCP/HP mixture to (1D) rod-like PFS micelles in a selective solvent as first-generation seeds. This leads to 2D platelet structures. If this step is conducted at a high supersaturation, secondary crystals form on the basal surface of these platelets. Co-crystallization and rapid crystallization of BCP/HP promote the formation of defects that act as nucleation sites for secondary crystals, resulting in multilayer platelets. This is the key step. The multilayer platelets serve as second-generation seeds upon subsequent addition of BCP/HP blends and, with increasing supersaturation, lead to the sequential formation of uniform (3D) hedrites, sheaves, and spherulites. Similar structures can also be obtained by a simple one-pot direct self-assembly (heating-cooling-aging) protocol of PFS BCP/HP blends. In this case, for a carefully chosen but narrow temperature range, PFS HPs nucleate formation of uniform structures, and the annealing temperature regulates the supersaturation level. In both protocols, the competitive crystallization kinetics of HP/BCP affects the morphology. Both protocols exhibit broad generality. We believe the morphological transformation from 2D to 3D structures, regulated by defect formation, co-crystallization, and supersaturation levels, could apply to various semicrystalline polymers. Moreover, the 3D structures are sufficiently robust to serve as recoverable carriers for nanoparticle catalysts, exhibiting valuable catalytic activity and opening new possibilities for applications requiring exquisite 3D structures.

4.
Biotechnol Adv ; 66: 108173, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37169102

RESUMO

Fluorescence-activated droplet sorting (FADS) has emerged as a powerful tool for ultrahigh-throughput screening of enzymes, metabolites, and antibodies. Fluorescence coupling strategies (FCSs) are key to the development of new FADS methods through their coupling of analyte properties such as concentration, activities, and affinity with fluorescence signals. Over the last decade, a series of FCSs have been developed, greatly expanding applications of FADS. Here, we review recent advances in FCS for different analyte types, providing a critical comparison of the available FCSs and further classification into four categories according to their principles. We also summarize successful FADS applications employing FCSs in enzymes, metabolites, and antibodies. Further, we outline possible future developments in this area.


Assuntos
Ensaios de Triagem em Larga Escala , Fluorescência
5.
J Am Chem Soc ; 145(2): 1247-1261, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36598864

RESUMO

Self-assembly of block copolymers (BCP) into uniform 3D structures in solution is an extremely rare phenomenon. Furthermore, the investigation of general prerequisites for fabricating a specific uniform 3D structure remains unknown and challenging. Here, through a simple one-pot direct self-assembly (heating and cooling) protocol, we show that uniform spherulite-like structures and their precursors can be prepared with various poly(ferrocenyldimethylsilane) (PFS) BCPs in a variety of polar and non-polar solvents. These structures all evolve from elongated lamellae into hedrites, sheaf-like micelles, and finally spherulites as the annealing temperature and supersaturation degree are increased. The key feature leading to this growth trajectory is the formation of secondary crystals by self-nucleation on the surface of early-elongated lamellae. We identified general prerequisites for fabricating PFS BCP spherulites in solution. These include corona/PFS core block ratios in the range of 1-5.5 that favor the formation of 2D structures as well as the development of secondary crystals on the basal faces of platelets at early stages of the self-assembly. The one-pot direct self-assembly provides a general protocol to form uniform spherulites and their precursors consisting of PFS BCPs that match these prerequisites. In addition, we show that manipulation of various steps in the direct self-assembly protocol can regulate the size and shape of the structures formed. These general concepts show promise for the fabrication and optimization of spherulites and their precursors from semicrystalline BCPs with interesting optical, electronic, or biomedical properties using the one-pot direct self-assembly protocol.

6.
J Am Coll Health ; 71(7): 2123-2130, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34469261

RESUMO

Background: Since the end of 2019, the coronavirus disease (COVID-19) outbreak rapidly became a pandemic. The psychological state of people during the COVID-19 pandemic has gained interest. Our aim was to study the prevalence of anxiety, depression, and stress in college students during the COVID-19 pandemic. Methods: A systematic search of Medline, Embase, Web of Science, and the Cochrane Library was conducted up to September 20, 2020. Reviewers independently assessed full-text articles according to predefined criteria. Stata14/SE was used to calculate the prevalence and 95% confidence intervals (CIs) of anxiety, depression, and stress among college students from different countries. A random effects model was adopted. The Egger test was used to determine publication bias. Results: A total of 280 references were retrieved, and 28 papers met our inclusion criteria, for a total of 436,799 college students. Thirteen studies involved non-Chinese college students, and 15 studies involved Chinese college students. The prevalence of anxiety, depression, and stress was 29% (95% CI, 19-25%), 37% (95% CI, 32-42%), and 23% (95% CI, 8-39%), respectively. Conclusion: The COVID-19 pandemic has had a negative psychological effect on college students, and the prevalence of anxiety, depression, and stress among Chinese college students is lower than among non-Chinese college students.

7.
Front Pharmacol ; 13: 1019451, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36523489

RESUMO

Feiyanning Formula (FYN), a Chinese herbal formula derived from summarized clinical experience, is proven to have anti-tumor effects in lung cancer patients. Osimertinib, a third-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI), can improve progression-free survival and overall survival of patients but drug resistance is inevitable. The current study evaluated the effects of FYN in osimertinib-resistant HCC827OR and PC9OR cells. FYN preferentially inhibited the proliferation and migration of HCC827OR and PC9OR cells. Moreover, FYN and osimertinib exhibited synergistic inhibitory effects on proliferation and migration. Real-time qPCR (RT-qPCR) and western blotting results indicated that FYN downregulated gene and protein levels of GSK3ß and SRFS1, which are enriched in the Wnt/ß-catenin pathway. Besides, FYN inhibited tumor growth and exhibited synergistic effects with osimertinib in vivo. Collectively, the results suggested that FYN exerted an anti-osimertinib resistance effect via the Wnt/ß-catenin pathway.

8.
Risk Manag Healthc Policy ; 15: 1751-1759, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36157290

RESUMO

Background: Many studies have shown that the pollution of fine particles in the air is related to the incidence of chronic diseases. However, research on air pollution and metabolism-associated fatty liver disease (MAFLD) is limited. Objective: The purpose of this study was to explore the relationship between short-term ambient air pollution and daily outpatient visits for metabolic-related fatty liver. Methods: We used a quasi-Poisson regression generalized additive model to stratify analyses by season, age, and gender. Results: From January 1, 2017, to August 31, 2019, 10,562 confirmed MAFLD outpatient visits were recorded. A 10 µg/m3 increase of fine particular matter (PM10and PM2.5) and NO2 concentrations corresponding with percent change were 0.82 (95% confidence interval [CI], 0.49-1.15), 0.57 (95% CI, 0.18-0.98), and 0.86 (95% CI, 0.59-1.13) elevation in MAFLD outpatient visits. In terms of season, the impact estimates of NO2 and PM2.5% change were 3.55 (95% CI, 1.23-5.87) and 1.12 (95% CI, 0.78-1.46) in the hot season and transition season, respectively. Compared with the warm season, the impact estimates of PM10were more significant in the cool season: 2.88 (95% CI, 0.66-5.10). NO2 has the greatest effect in the transition season, whereas PM10 has the greatest highest effect in the cool and hot seasons. Compared with other pollutants, PM2.5 has the greatest impact in the age stratification, which percent change are 2.69 (95% CI, 0.77-5.61) and 2.88 (95% CI, 0.37-6.40) respectively. The impact values of PM2.5 in male and female percent change were 3.60 (95% CI, 0.63-6.57) and 1.65 (95% CI, 1.05-2.25), respectively. Conclusion: This study shows that the air pollutants are related to the number of outpatient visits for MAFLD. The effects of different air pollutants on MAFLD outpatient visits were different by season, ages, and gender.

9.
Front Endocrinol (Lausanne) ; 13: 935390, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928895

RESUMO

Background and Aim: Non-alcoholic fatty liver disease (NAFLD) is closely related to cardiovascular diseases (CVD). A newly proposed definition is metabolic dysfunction-associated fatty liver disease (MAFLD), which was changed from NAFLD. The clinical effect of this change on abnormalities of cardiac structure and function is yet unknown. We aimed to examine whether MAFLD is associated with left ventricular (LV) diastolic dysfunction (LVDD) and cardiac remolding and further identify the impact of different subgroups and severity of MAFLD. Method: We evaluated 228 participants without known CVDs. Participants were categorized by the presence of MAFLD and the normal group. Then, patients with MAFLD were subclassified into three subgroups: MAFLD patients with diabetes (diabetes subgroup), overweight/obesity patients (overweight/obesity subgroup), and lean/normal-weight patients who had two metabolic risk abnormalities (lean metabolic dysfunction subgroup). Furthermore, the severity of hepatic steatosis was assessed by transient elastography (FibroScan®) with a controlled attenuation parameter (CAP), and patients with MAFLD were divided into normal, mild, moderate, and severe hepatic steatosis groups based on CAP value. Cardiac structure and function were examined by echocardiography. Results: LVDD was significantly more prevalent in the MAFLD group (24.6% vs. 60.8%, p < 0.001) compared to the normal group. The overweight subgroup and diabetes subgroup were significantly associated with signs of cardiac remolding, including interventricular septum thickness, LV posterior wall thickness, left atrial diameter (all p < 0.05), relative wall thickness, and LV mass index (all p < 0.05). Additionally, moderate-to-to severe steatosis patients had higher risks for LVDD and cardiac remolding (all p-values < 0.05). Conclusion: MAFLD was associated with LVDD and cardiac remolding, especially in patients with diabetes, overweight patients, and moderate-to-to severe steatosis patients. This study provides theoretical support for the precise prevention of cardiovascular dysfunction in patients with MAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Disfunção Ventricular Esquerda , Diástole , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Obesidade/complicações , Sobrepeso/complicações , Disfunção Ventricular Esquerda/etiologia
10.
Chem Sci ; 13(2): 396-409, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35126972

RESUMO

Self-assembly of crystalline-coil block copolymers (BCPs) in selective solvents is often carried out by heating the mixture until the sample appears to dissolve and then allowing the solution to cool back to room temperature. In self-seeding experiments, some crystallites persist during sample annealing and nucleate the growth of core-crystalline micelles upon cooling. There is evidence in the literature that the nature of the self-assembled structures formed is independent of the annealing time at a particular temperature. There are, however, no systematic studies of how the rate of cooling affects self-assembly. We examine three systems based upon poly(ferrocenyldimethylsilane) BCPs that generated uniform micelles under typical conditions where cooling took pace on the 1-2 h time scale. For example, several of the systems generated elongated 1D micelles of uniform length under these slow cooling conditions. When subjected to rapid cooling (on the time scale of a few minutes or faster), branched structures were obtained. Variation of the cooling rate led to a variation in the size and degree of branching of some of the structures examined. These changes can be explained in terms of the high degree of supersaturation that occurs when unimer solutions at high temperature are suddenly cooled. Enhanced nucleation, seed aggregation, and selective growth of the species of lowest solubility contribute to branching. Cooling rate becomes another tool for manipulating crystallization-driven self-assembly and controlling micelle morphologies.

11.
Medicine (Baltimore) ; 101(49): e31525, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36626456

RESUMO

OBJECTIVE: To observe the clinical effect of Shenxiang Suhe Pill in the treatment of coronary heart disease (CHD) patients with nonalcoholic fatty liver disease (NAFLD). METHODS: 56 CHD patients with NAFLD were randomly divided into an experimental group and control group. The control group was treated by conventional western medicines, while the experimental group was given Shenxiang Suhe Pill in addition to the treatment of the control group. Both groups were treated for 12 weeks. Before treatment and after 12 weeks of treatment, the clinical efficacy indices of the 2 groups were evaluated, including transient elastic B-ultrasound (Fibroscan), controlled attenuation parameter (CAP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), low density lipoprotein cholesterol, high density lipoprotein cholesterol, triglyceride (TG), total cholesterol, high sensitivity-reactive protein (hs-CRP) and lactate dehydrogenase (LDH). RESULTS: Compared with the control group, the CAP value of the experimental group decreased more significantly, and the severity classification of NAFLD was also significantly improved (P < .05). LDH and hs-CRP in the experimental group decreased after treatment (P < .05). TG and high density lipoprotein cholesterol indicators improved more in the experimental group than in the control group (P < .05). ALT and AST in neither group showed significant change (P > .05). CONCLUSION: Shenxiang Suhe Pills has a significant overall curative effect in the treatment of patients with CHD complicated with NAFLD. It can reduce liver lipid deposition, reduce the severity of NAFLD, and has lipid-lowering and anti -inflammatory effects.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estudos de Casos e Controles , Proteína C-Reativa , HDL-Colesterol , Triglicerídeos , Alanina Transaminase/metabolismo , Fígado/metabolismo
12.
Ir J Med Sci ; 191(2): 563-567, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34018158

RESUMO

AIMS: We aimed to evaluate the impact of the COVID-19 epidemic on emergency and cardiovascular disease-related calls in Hangzhou, China. METHODS: We conducted a single-center retrospective study, collecting data on emergency calls to the Hangzhou Emergency Center (HEC) during the COVID-19 epidemic (January 20, 2020, to March 15, 2020). Data were compared with the same period in 2019. RESULTS: Compared to 2019, the number of emergency calls has dropped by 21.63%, ambulance calls by 29.02%, rescue calls by 22.57%, and cardiovascular disease-related emergency calls by 32.86%. The numbers of emergency, ambulance, and rescue calls in 2020 were significantly lower than in 2019. CONCLUSIONS: During the COVID-19 epidemic in Hangzhou, the numbers of emergency and cardiovascular disease-related calls have decreased significantly. These results point to a severe social problem that requires the attention of the medical community and the government.


Assuntos
COVID-19 , Doenças Cardiovasculares , COVID-19/epidemiologia , Doenças Cardiovasculares/epidemiologia , China/epidemiologia , Humanos , Estudos Retrospectivos , SARS-CoV-2
13.
Risk Manag Healthc Policy ; 14: 5027-5038, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34938138

RESUMO

PURPOSE: To compare food safety knowledge, attitudes, and self-reported practices among medical staff in China before, during, and after the COVID-19 pandemic. PATIENTS AND METHODS: The questionnaire was anonymous. All respondents were Chinese medical personnel. A Chi-square contingency table was used to compare the knowledge and attitudes of Chinese medical staff before, during and after COVID-19. R statistical software (v4.0.0) was used for analysis. RESULTS: A total of 1431 valid responses (57.3% from female respondents) were included in our analysis. Medical professionals were geographically distributed as follows: eastern China, 55.5%; central China, 19.7%; western China, 24.1%; Hong Kong, Macau, or Taiwan, 0.05%. Medical professionals reported that they paid greater attention to food safety after the COVID-19 pandemic compared with before the epidemic. Self-reported knowledge of and attitudes toward food safety among medical staff were significantly different before, during, and after the COVID-19 pandemic (both P<0.001). CONCLUSION: After the COVID-19 pandemic, medical professionals paid increasing attention to food safety, which is a clinically important change. Because medical professionals can influence public understanding of food safety, their increased attention to this subject may enable them to promote food safety knowledge more actively in their work. This may in turn promote a better understanding of food safety and protect the health of the general public.

14.
Risk Manag Healthc Policy ; 14: 4393-4399, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34729027

RESUMO

BACKGROUND AND AIM: Relevant studies show that population migration has a great impact on the early spread of infectious diseases. Therefore, it is important to explore whether there is an explicit relationship between population migration and the number of confirmed cases for the control of the COVID-19 epidemic. This paper mainly explores the impact of population migration on early COVID-19 transmission, and establishes a predictive nonlinear mathematical model to predict the number of early cases. METHODS: Data of confirmed cases were sourced from the official website of the Municipal Health Committee, and the proportions of migration from Wuhan to other cities were sourced from the Baidu data platform. The data of confirmed cases and the migration proportions of 14 cities in Hubei Province were collected, the COVID-19 cases study period was determined as 10 days based on the third quartile of the interval of the incubation period, and a non-linear mathematical model was constructed to clarify the relationship between the migration proportion and the number of confirmed COVID-19 cases. Finally, eight typical regions were selected to verify the accuracy of the model. RESULTS: The daily population migration rates and the growth curves of the number of confirmed cases in the 14 cities were basically consistent, and Pearson's correlation coefficient was 0.91. The specific mathematical expression of 14 regions is . In each of the fourteen cities, The nonlinear exponential model structure is as follows:. It was found that the R 2 values of the fitted mathematical model were greater than 0.8 in all studied regions, excluding Suizhou (p < 0.05). The established mathematical model was used to fit eight regions in China, and the correlations between the predicted and actual numbers of confirmed cases were greater than 0.9, excluding that of Hebei Province (0.82). CONCLUSION: The study found that population migration has a positive and significant impact on the spread of COVID-19. Modeling COVID-19 risk may be a useful strategy for directing public health surveillance and interventions. Restricting the migration of the population is of great significance to the joint prevention and control of the pandemic worldwide.

15.
Front Public Health ; 9: 709056, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34409011

RESUMO

Background: The coronavirus pneumonia is still spreading around the world. Much progress has been made in vaccine development, and vaccination will become an inevitable trend in the fight against this pandemic. However, the public acceptance of COVID-19 vaccination still remains uncertain. Methods: An anonymous questionnaire was used in Wen Juan Xing survey platform. All the respondents were divided into healthcare workers and non-healthcare workers. Multinomial logistic regression analyses were performed to identify the key sociodemographic, cognitive, and attitude associations among the samples of healthcare workers and non-healthcare workers. Results: A total of 2,580 respondents completed the questionnaire, including 1,329 healthcare workers and 1,251 non-healthcare workers. This study showed that 76.98% of healthcare workers accepted the COVID-19 vaccine, 18.28% workers were hesitant, and 4.74% workers were resistant. Among the non-healthcare workers, 56.19% workers received the COVID-19 vaccine, 37.57% workers were hesitant, and 6.24% workers were resistant. Among the healthcare workers, compared with vaccine recipients, vaccine-hesitant individuals were more likely to be female (AOR = 1.52, 95% CI: 1.12-2.07); vaccine-resistant individuals were more likely to live in the suburbs (AOR = 2.81, 95% CI: 1.44-3.99) with an income of 10,000 RMB or greater (AOR = 2.00, 95% CI: 1.03-3.90). Among the non-healthcare workers, vaccine-hesitant individuals were more likely to be female (AOR = 1.66, 95% CI: 1.31-2.11); vaccine-resistant individuals were also more likely to be female (AOR = 1.87, 95% CI: 1.16-3.02) and older than 65 years (AOR = 4.96, 95% CI: 1.40-7.62). There are great differences between healthcare workers and non-healthcare workers in their cognition and attitude toward vaccines. Conclusions: Our study shows that healthcare workers are more willing to be vaccinated than non-healthcare workers. Current vaccine safety issues continue to be a major factor affecting public acceptance, and to expand vaccine coverage in response to the COVID-19 pandemic, appropriate vaccination strategies and immunization programs are essential, especially for non-healthcare workers.


Assuntos
Vacinas contra COVID-19 , COVID-19 , China/epidemiologia , Estudos Transversais , Feminino , Pessoal de Saúde , Humanos , Masculino , Pandemias , SARS-CoV-2 , Inquéritos e Questionários , Vacinação
16.
Risk Manag Healthc Policy ; 14: 2369-2375, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34135649

RESUMO

BACKGROUND: Many people have experienced novel coronavirus pneumonia since the beginning of the COVID-19 pandemic in Wuhan, China. The Chinese government has encouraged people to wear face masks in public places; however, due to the large population, there may be a series of problems related to this recommendation, including shortages of masks and lack of an optimal disposal method for used masks. OBJECTIVE: The purpose of this study is to understand the current status of mask shortages and used masks in China. METHODS: A questionnaire survey was designed to assess the current status of mask shortages and used masks. The differences among groups were analyzed with chi-square tests. RESULTS: The constituent ratio of those who reuse masks was 61%. Obtaining masks from the drugstore was reported to be very difficult due to high demand and short supply, and approximately 1/3 of the respondents purchased expensive masks. Most people know how to properly handle used masks, and only 7% of them casually discard masks. However, 50% of respondents have seen others throw away used masks at will. A further subgroup analysis showed that respondents in Central China tended to use masks repeatedly, as did medical personnel. Females, people living in the central region, and medical personnel may find it more difficult to purchase masks in drugstores. Non-medical personnel may be more likely to buy expensive masks. Females, people living in the western region, and medical personnel may be more likely to know how to properly handle used masks and not to discard used masks at will. Medical personnel may be more likely to observe others discarding used masks at will. CONCLUSION: In response to COVID-19, the public should be encouraged to use face masks and are advised not to reuse or throw away masks at will due to safety concerns.

17.
Nat Prod Rep ; 38(7): 1282-1329, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-33351014

RESUMO

Covering: 1976 to 2020. Although constituting a limited chemical family, phytostilbenes represent an emblematic group of molecules among natural compounds. Ever since their discovery as antifungal compounds in plants and their ascribed role in human health and disease, phytostilbenes have never ceased to arouse interest for researchers, leading to a huge development of the literature in this field. Owing to this, the number of references to this class of compounds has reached the tens of thousands. The objective of this article is thus to offer an overview of the different aspects of these compounds through a large bibliography analysis of more than 500 articles. All the aspects regarding phytostilbenes will be covered including their chemistry and biochemistry, regulation of their biosynthesis, biological activities in plants, molecular engineering of stilbene pathways in plants and microbes as well as their biotechnological production by plant cell systems.


Assuntos
Agroquímicos/química , Compostos Fitoquímicos/química , Estilbenos/química , Aciltransferases , Biotecnologia , Fungicidas Industriais , Engenharia Metabólica , Plantas/química
18.
Angew Chem Int Ed Engl ; 58(35): 12096-12101, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31246340

RESUMO

The photophysical process of localized surface plasmon resonance (LSPR) is, for the first time, exploited for broadband photon harvesting in photo-regulated controlled/living radical polymerization. Efficient macromolecular synthesis was achieved under illumination with light wavelengths extending from the visible to the near-infrared regions. Plasmonic Ag nanostructures were in situ generated on Ag3 PO4 photocatalysts in a reversible addition-fragmentation chain transfer (RAFT) system, thereby promoting polymerization of various monomers following a LSPR-mediated electron transfer mechanism. Owing to the LSPR-enhanced broadband photon harvesting, high monomer conversion (>99 %) was achieved under natural sunlight within 0.8 h. The deep penetration of NIR light enabled successful polymerization with reaction vessels screened by opaque barriers. Moreover, by trapping active oxygen species generated in the photocatalytic process, polymerization could be implemented without pre-deoxygenation.

19.
Angew Chem Int Ed Engl ; 57(37): 12037-12042, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30043508

RESUMO

A key challenge of photoregulated living radical polymerization is developing efficient and robust photocatalysts. Now carbon dots (CDs) have been exploited for the first time as metal-free photocatalysts for visible-light-regulated reversible addition-fragmentation chain-transfer (RAFT) polymerization. Screening of diverse heteroatom-doped CDs suggested that the P- and S-doped CDs were effective photocatalysts for RAFT polymerization under mild visible light following a photoinduced electron transfer (PET) involved oxidative quenching mechanism. PET-RAFT polymerization of various monomers with temporal control, narrow dispersity (D≈1.04), and chain-end fidelity was achieved. Besides, it was demonstrated that the CD-catalyzed PET-RAFT polymerization was effectively performed under natural solar irradiation.

20.
J Agric Food Chem ; 66(17): 4431-4438, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29671328

RESUMO

Salidroside is an important plant-derived aromatic compound with diverse biological properties. Because of inadequate natural resources, the supply of salidroside is currently limited. In this work, we engineered the production of salidroside in yeast. First, the aromatic aldehyde synthase (AAS) from Petroselinum crispum was overexpressed in Saccharomyces cerevisiae when combined with endogenous Ehrlich pathway to produce tyrosol from tyrosine. Glucosyltransferases from different resources were tested for ideal production of salidroside in the yeast. Metabolic flux was enhanced toward tyrosine biosynthesis by overexpressing pathway genes and eliminating feedback inhibition. The pathway genes were integrated into yeast chromosome, leading to a recombinant strain that produced 239.5 mg/L salidroside and 965.4 mg/L tyrosol. The production of salidroside and tyrosol reached up to 732.5 and 1394.6 mg/L, respectively, by fed-batch fermentation. Our work provides an alternative way for industrial large-scale production of salidroside and tyrosol from S. cerevisiae.


Assuntos
Glucosídeos/biossíntese , Engenharia Metabólica/métodos , Microrganismos Geneticamente Modificados/genética , Saccharomyces cerevisiae/genética , Fermentação , Expressão Gênica , Glucose/metabolismo , Microrganismos Geneticamente Modificados/metabolismo , Petroselinum/enzimologia , Petroselinum/genética , Fenóis , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/metabolismo , Saccharomyces cerevisiae/metabolismo , Tirosina/metabolismo
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