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1.
Artigo em Inglês | MEDLINE | ID: mdl-38394917

RESUMO

Due to three free hydroxyl groups, hydroxytyrosol (HT) presents strong bioactivity and has broad food and drug application prospects. However, there is no good separation and purification technology. In this study, separation and purification technology of HT from the ethyl acetate extraction of enzymatic hydrolysate from olive leaf (EEEH) was investigated with macroporous adsorption resin (MAR) and high-speed counter-current chromatography (HSCCC) and the separation factors were optimized. First, the adsorption properties of eight MARs (AB-8, S-8, D-101, X-5, XAD-1, XAD-5, NKA-Ⅱ, H-103) for HT enrichment were studied. The results showed that H-103 macroporous resin was adsorbent, sample concentration was 1.5 mg/mL, eluent was 30 % ethanol solution, sample loading rate was 3.0 BV/h, elution velocity was 2.0 BV/h, and HT purity of EEEH was increased from 10.23 % to 40.78 %. Then, solvent systems were examined according to partition coefficients of target component and petroleum ether: ethyl acetate: methanol: water (4:6:4:6, v/v) system was chosen. The critical experimental parameters of HSCCC were optimized as following: revolution speed was 1200 rpm and flow rate was 3 mL/min. The HT purity of macroporous resin purified EEEH was increased from 40.78 % to 85.7 %. Therefore, MAR-HSCCC combined technology could be a very effective approach to separate and purify HT from EEEH.


Assuntos
Acetatos , Olea , Álcool Feniletílico/análogos & derivados , Adsorção , Solventes , Cromatografia , Folhas de Planta , Distribuição Contracorrente/métodos , Cromatografia Líquida de Alta Pressão/métodos
2.
Influenza Other Respir Viruses ; 17(12): e13226, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38090226

RESUMO

The sentinel hospital-based influenza-like illness (ILI) surveillance network was established in China since the 2009 H1N1 pandemic. This network plays important roles in monitoring influenza virus variation and identifying novel respiratory pathogens. In this study, we characterized the pathogen spectrum pattern (PSP) of ILI based on three sentinel hospitals and analyzed the significant change of PSP during the COVID-19 epidemic. The notable change of influenza virus spectrum was observed since the beginning of COVID-19 outbreak, and we found persistent domination of Victoria lineage of influenza B virus and "extinction" of A/H1N1, A/H3N2, and B/Yamagata during the dynamic Zero-COVID-19 pandemic in Nanchang, China. However, these strains intermittently co-circulated before the COVID-19.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Humanos , Vírus da Influenza B/genética , Influenza Humana/epidemiologia , Vírus da Influenza A Subtipo H3N2 , Pandemias , COVID-19/epidemiologia , China/epidemiologia
3.
Front Microbiol ; 14: 1251683, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37920267

RESUMO

Introduction: Pathogen spectrum of Hand, foot and mouth disease (HFMD) has substantially changed in the past decade in China. Growing evidence has indicated that anti-COVID-19 nonpharmaceutical interventions (NPIs) can support control of various infectious diseases, including intestinal diseases. Methods: In this study, HFMD cases were enrolled from sentinel hospitals of Nanchang, Jiangxi province, and enteroviruses were genotyped using specific real time RT-PCR. We systematically characterized the epidemiology of HFMD based on the continuous molecular surveillance and estimated the impact of COVID-19 intervention on HFMD incidence using seasonal autoregressive integrated moving average (ARIMA) models. Results: A total of 10247 HFMD cases were included during 2010-2022, of which 6121 enterovirus (EV)-positive cases (59.7%) were identified by real-time RT-PCR. Over 80% cases were associated with EV-A71 and coxsackievirus A16 (CVA16) during 2010-2012, while the type distribution significantly changed as CVA6 emerged to be dominant, accounting for 22.6%-59.6% during 2013-2022. It was observed that the prevalence patterns of EV-A71 and CVA16 were similar and both of them peaked in the second quarter and then leveled off. However, CVA6 was generally prevalent around the fourth quarter, demonstrating a staggered prevalence during 2010-2019. During the COVID-19 epidemic, the seasonal HFMD epidemic peak was restrained, and the ARIMA analysis indicated that the COVID-19 intervention had mitigated EV transmission during the first COVID-19 outbreak in early 2020. In addition, bivariate Spearman's cross-correlation coefficients were estimated for the major types CVA6, CVA16 and EV-A71. Our analyses indicated the possible existence of correlations among CVA6, CVA16 and EV-A71 prevalence in the epidemiological level. Discussion: Taken together, the type distribution of HFMD has substantially changed over the last decade and CVA6 and CVA16 are currently the most predominant types co-circulating in Nanchang. The anti-COVID-19 NPIs significantly reduced the incidence of EV infections.

4.
J Colloid Interface Sci ; 590: 641-651, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33582366

RESUMO

This paper reports the usage ratio of TEOS and Zr(OBu)4 on the formation of Ni@ZrO2 yolk-shell for dry reforming of methane. From XPS analysis, the ZrO2 hollow shell texture is demonstrated to be [TEOS]/[Zr(OBu)4] dependent due to different sizes of SiO2 produced. It found that an adequate ratio of [TEOS]/[Zr(OBu)4] improves the catalytic conversion of dry reforming of methane. It (Ni@ZrO2-SiZr-7.7) shows 90% conversion for CH4 and 93% for CO2 at a WHSV of 72,000 mLgcat-1h-1 for 50 h at 800 °C with TOFCH4 of 8.7 s-1. It proposed that the changes in surface Si/Zr and gradual interconnecting pores contributed to its activity and stability. These finding's potential to be utilized in other high-temperature reactions.

5.
Front Microbiol ; 12: 811553, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069515

RESUMO

After the first national-scale outbreak of Hand, foot, and mouth disease (HFMD) in China, a national surveillance network was established. Here we described the epidemiology and pathogenic profile of HFMD and the impact of EV-A71 vaccination on pathogen spectrum of enteroviruses in the southeastern Chinese city of Nanchang during 2010-2019. A total of 7,951 HFMD cases from sentinel hospitals were included, of which 4,800 EV-positive cases (60.4%) were identified by real-time RT-PCR. During 2010-2012, enterovirus 71 (EV-A71) was the main causative agent of HFMD, causing 63.1% of cases, followed by 19.3% cases associated with coxsackievirus A16 (CV-A16). Since 2013, the proportion of other enteroviruses has increased dramatically, with the sub genotype D3 strain of Coxsackievirus A6 (CV-A6) replacing the dominance of EV-A71. These genetically diverse native strains of CV-A6 have co-transmitted and co-evolved in Nanchang. Unlike EV-A71 and CV-A16, most CV-A6 infections were concentrated in autumn and winter. The incidence of EV-A71 infection negatively correlated with EV-A71 vaccination (r = -0.990, p = 0.01). And severe cases sharply declined as the promotion of EV-A71 vaccines. After 2-year implementation of EV-A71 vaccination, EV-A71 is no longer detected from the reported HFMD cases in Nanchang. In conclusion, EV-A71 vaccination changed the pattern of HFMD epidemic, and CV-A6 replaced the dominance of EV-A71 over time.

6.
J Microbiol ; 58(1): 78, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31898256

RESUMO

In the article by Wu et al. published in Journal of Microbiology 2019; 57, 1105-1114, the figure 8 is unfortunately incorrect. The figure 8 should be corrected as below.

7.
J Microbiol ; 57(12): 1105-1114, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31686391

RESUMO

In order to adapt to different environments, Vibrio parahaemolyticus employed a complicated quorum sensing system to orchestrate gene expression and diverse colony morphology patterns. In this study, the function of the putative quorum sensing signal synthase gene cqsA (VPA0711 in V. Parahaemolyticus strain RIMD2210633 genome) was investigated. The cloning and expression of V. parahaemolyticus cqsA in Escherichia coli system induced the production of a new quorum sensing signal that was found in its culture supernatant. The signal was purified by high performance liquid chromatography methods and determined to be 3-hydroxyundecan- 4-one by indirect and direct mass spectra assays. The deletion of cqsA in RIMD2210633 changed V. parahaemolyticus colony morphology from the classical 'fried-egg' shape (thick and opaque in the center, while thin and translucent in the edge) of the wild-type colony to a 'pancake' shape (no significant difference between the centre and the edge) of the cqsA deleted colony. This morphological change could be restored by complementary experiment with cqsA gene or the signal extract. In addition, the expression of opaR, a well-known quorum sensing regulatory gene, could be up-regulated by cqsA deletion. Our results suggested that V. parahaemolyticus used cqsA to produce 3-hydroxyundecan-4-one signal and thereby regulated colony morphology and other quorum sensing-associated behaviors.


Assuntos
Proteínas de Bactérias/metabolismo , Percepção de Quorum , Transdução de Sinais , Vibrio parahaemolyticus/metabolismo , Proteínas de Bactérias/genética , Clonagem Molecular , DNA Bacteriano/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Deleção de Genes , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos/genética , Fenótipo , Fatores de Transcrição/metabolismo , Vibrio/genética , Vibrio/crescimento & desenvolvimento , Vibrio/metabolismo , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/crescimento & desenvolvimento
8.
Molecules ; 23(2)2018 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-29438312

RESUMO

The thermal decomposition behavior of olive hydroxytyrosol (HT) was first studied using thermogravimetry (TG). Cracked chemical bond and evolved gas analysis during the thermal decomposition process of HT were also investigated using thermogravimetry coupled with infrared spectroscopy (TG-FTIR). Thermogravimetry-Differential thermogravimetry (TG-DTG) curves revealed that the thermal decomposition of HT began at 262.8 °C and ended at 409.7 °C with a main mass loss. It was demonstrated that a high heating rate (over 20 K·min-1) restrained the thermal decomposition of HT, resulting in an obvious thermal hysteresis. Furthermore, a thermal decomposition kinetics investigation of HT indicated that the non-isothermal decomposition mechanism was one-dimensional diffusion (D1), integral form g(x) = x², and differential form f(x) = 1/(2x). The four combined approaches were employed to calculate the activation energy (E = 128.50 kJ·mol-1) and Arrhenius preexponential factor (ln A = 24.39 min-1). In addition, a tentative mechanism of HT thermal decomposition was further developed. The results provide a theoretical reference for the potential thermal stability of HT.


Assuntos
Antioxidantes/química , Nitrogênio/química , Álcool Feniletílico/análogos & derivados , Antioxidantes/isolamento & purificação , Temperatura Alta , Cinética , Olea/química , Álcool Feniletílico/química , Álcool Feniletílico/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Termogravimetria
9.
Molecules ; 22(6)2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28538693

RESUMO

Due to the multiple hydroxyl groups in its structure, hydroxytyrosol (HT) is very sensitive to air and light and has very strong instability and hydrophilicity that affect its biological activity. This study attempted to prepare liposomes containing water-soluble HT to improve the bioavailability and biocompatibility of the target drug. The preparation process factors (temperature, mass ratio of phospholipid (PL) and cholesterol (CH), Tween-80 volume, HT mass) were studied and response surface methodology (RSM) was applied to optimize the conditions. The results demonstrated that by using a temperature of 63 °C, mass ratio of PL and CH 4.5:1, HT mass 5 mg and Tween-80 volume of 6 mL, HT liposomes with an encapsulation efficiency (EE) of 45.08% were prepared. It was found that the particle sizes of the HT liposomes were well distributed in the range of 100-400 nm. Compared to free HT, prepared HT liposomes had better stability and a distinct slow release effect in vitro. Besides, HT liposomes presented better DPPH radical scavenging activity than free HT, which could be due to the fact that HT was encapsulated fully inside the liposomes. In addition, the encapsulation mechanism of HT was evaluated. In summary, the results indicated that HT liposome could enhance the antioxidant activity and was a promising formulation for prolonging the biological activity time of the target drug.


Assuntos
Antioxidantes/química , Lipossomos/química , Olea/química , Álcool Feniletílico/análogos & derivados , Água/química , Álcool Feniletílico/química
10.
Microbes Infect ; 17(1): 48-53, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25284683

RESUMO

Multiple reassortment events within poultry and wild birds had resulted in the establishment of another novel avian influenza A(H10N8) virus, and finally resulted in human death in Nanchang, China. However, there was a paucity of information on the prevalence of avian influenza virus in poultry and wild birds in Nanchang area. We investigated avian influenza virus in poultry and wild birds from live poultry markets, poultry countyards, delivery vehicles, and wild-bird habitats in Nanchang. We analyzed 1036 samples from wild birds and domestic poultry collected from December 2013 to February 2014. Original biological samples were tested for the presence of avian influenza virus using specific primer and probe sets of H5, H7, H9, H10 and N8 subtypes by real-time RT-PCR. In our analysis, the majority (97.98%) of positive samples were from live poultry markets. Among the poultry samples from chickens and ducks, AIV prevalence was 26.05 and 30.81%, respectively. Mixed infection of different HA subtypes was very common. Additionally, H10 subtypes coexistence with N8 was the most prevalent agent during the emergence of H10N8. This event illustrated a long-term surveillance was so helpful for pandemic preparedness and response.


Assuntos
Vírus da Influenza A Subtipo H10N8/isolamento & purificação , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Animais , Aves , China/epidemiologia , Monitoramento Epidemiológico , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H10N8/genética , Neuraminidase/genética , Aves Domésticas , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Virais/genética
11.
Artigo em Chinês | MEDLINE | ID: mdl-25509770

RESUMO

OBJECTIVE: To investigate the short-term effectiveness of minimally invasive percutaneous plate osteosynthesis (MIPPO) in treatment of anterior pelvic ring fractures. METHODS: Between January 2012 and October 2013, 16 patients with anterior pelvic ring fractures were treated with MIPPO. There were 10 males and 6 females at the age of 20-63 years (mean, 41 years). The causes of injury were traffic accident in 9 cases and falling from height in 7 cases. The duration of injury to admission was 2 hours to 5 days (mean, 1 day). According to Tile classification, 8 cases were rated as type B2, 4 cases as type B3, 2 cases as type C1, and 2 cases as type C2. Of them, 2 cases had iliac wing fracture, and 4 cases had pelvic posterior ring fracture. The time from admission to operation was 3-12 days (mean, 6 days). RESULTS: The bleeding volume was 60-120 mL (mean, 70 mL). All wounds healed by first intention. No postoperative complication of deep venous thrombosis or long-term continuous pain occurred. All cases were followed up 5-27 months (mean, 11.5 months). No clinical manifestation of lateral femoral cutaneous nerve injury or spermatic cord injury was found, and cremasteric reflex existed in males. All cases obtained bony union, and the healing time was 12-16 weeks (mean, 13 weeks). During the follow-up period, no loss of fracture reduction and no internal fixation loosening or broken were observed. According to Matta radiological evaluation criterion, 16 cases had anatomical reduction, and 3 cases had satisfactory reduction; according to Majeed scoring system of pelvic fracture, the results were excellent in 12 cases and good in 4 cases. CONCLUSION: MIPPO for treatment of anterior pelvic ring fractures has the advantages of less intraoperative blood loss, few soft tissue complications, and low infection rate, and can get satisfactory short- term effectiveness.


Assuntos
Fixação Interna de Fraturas/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Ossos Pélvicos/lesões , Ossos Pélvicos/cirurgia , Placas Ósseas , Parafusos Ósseos , Feminino , Fraturas Ósseas/cirurgia , Humanos , Plexo Lombossacral , Masculino , Lesões do Pescoço , Complicações Pós-Operatórias , Fraturas da Coluna Vertebral , Cicatrização
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