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1.
J Ethnopharmacol ; 329: 118130, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38565407

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Psoraleae Fructus (Bu Gu Zhi) is the fruit of Psoralea corylifolia L. (PCL) and has been used for centuries in traditional Chinese medicine formulas to treat osteoporosis (OP). A new drug called "BX" has been developed from PCL, but its mechanism for treating OP is not yet fully understood. AIM OF THE STUDY: To explore the mechanism of action of BX in the treatment of ovariectomy-induced OP based function-oriented multi-omics analysis of gut microbiota (GM) and metabolites. MATERIALS AND METHODS: C57BL/6 mice were bilaterally ovariectomized to replicate the OP model. The therapeutic efficacy of BX was evaluated by bone parameters (BMD, BV/TV, Tb.N, Tb.Sp), hematoxylin and eosin (H&E) staining results, and determination of bone formation markers procollagen type Ⅰ amino-terminal peptide (PⅠNP) and bone-specific alkaline phosphatase (BALP). Serum and fecal metabolomics and high-throughput 16S rDNA sequencing were performed to evaluate effects on endogenous metabolites and GM. In addition, an enzyme-based functional correlation algorithm (EBFC) algorithm was used to investigate functional correlations between GM and metabolites. RESULTS: BX improved OP in OVX mice by increasing BMD, BV/TV, serum PⅠNP, BALP, and improving Tb.N and Tb.Sp. A total of 59 differential metabolites were identified, and 9 metabolic pathways, including arachidonic acid metabolism, glycerophospholipid metabolism, purine metabolism, and tryptophan metabolism, were found to be involved in the progression of OP. EBFC analysis results revealed that the enzymes related to purine and tryptophan metabolism, which are from Lachnospiraceae_NK4A136_group, Blautia, Rs-E47_termite_group, UCG-009, and Clostridia_UCG-014, were identified as the intrinsic link between GM and metabolites. CONCLUSIONS: The regulation of GM and restoration of metabolic disorders may be the mechanisms of action of BX in alleviating OP. This research provides insights into the function-oriented mechanism discovery of traditional Chinese medicine in the treatment of OP.

2.
J Phys Chem A ; 128(13): 2643-2655, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38530707

RESUMO

Using reactive force field (ReaxFF) and molecular dynamics simulation, we investigate the combustion process of hydrogen-oxygen systems in initial thermal nonequilibrium states with different translational and rovibrational temperatures for oxygen. The system studied in this work contains 300 oxygen molecules and 700 hydrogen molecules with a density of 7 times the air density. For this system, the characteristic relaxation times of oxygen and hydrogen vibrational energies are 0.173 and 0.249 ns, respectively. 0.6% of hydrogen undergoes a chemical reaction with oxygen during the thermal nonequilibrium relaxation stage. For the distribution of translational energy and vibrational energy of oxygen in the thermal nonequilibrium state, the maximum mean error of the statistical distribution in the simulation and the Boltzmann distribution at temperature calculated from the average kinetic energy of molecules is about 2.25 × 10-5. At the same time, it was observed in the simulation that many-body interactions play a certain role in the combustion process. Furthermore, we compare the ignition time and temperature rise behavior of different combustion mechanisms and molecular dynamics simulations starting from the thermal equilibrium state. These results will provide meaningful references for the construction of thermal nonequilibrium combustion chemical reaction mechanisms.

3.
Viruses ; 16(2)2024 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-38400087

RESUMO

African swine fever (ASF) is a lethal contagious viral disease of domestic pigs and wild boars caused by the African swine fever virus (ASFV). The pandemic spread of ASF has caused severe effects on the global pig industry. Whole-genome sequencing provides crucial information for virus strain characterization, epidemiology analysis and vaccine development. Here, we evaluated the performance of next-generation sequencing (NGS) in generating ASFV genome sequences from clinical samples. Thirty-four ASFV-positive field samples including spleen, lymph node, lung, liver and blood with a range of Ct values from 14.73 to 25.95 were sequenced. For different tissue samples collected from the same sick pigs, the proportion of ASFV reads obtained from the spleen samples was 3.69-9.86 times higher than other tissues. For the high-viral-load spleen samples (Ct < 20), a minimum of a 99.8% breadth of ≥10× coverage was revealed for all the samples. For the spleen samples with Ct ≥ 20, 6/12 samples had a minimum of a 99.8% breadth of ≥10× coverage. A high average depth of sequencing coverage was also achieved from the blood samples. According to our results, high-quality ASFV whole-genome sequences could be obtained from the spleen or blood samples with Ct < 20. The high-quality ASFV genome sequence generated in this study was further used for the high-resolution phylogenetic analysis of the ASFV genomes in the early stage of the ASF epidemic in China. Our study demonstrates that NGS may act as a useful tool for efficient ASFV genome characterization, providing valuable information for disease control.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Vírus da Febre Suína Africana/genética , Filogenia , Sus scrofa , Sequenciamento de Nucleotídeos em Larga Escala
4.
Virus Res ; 339: 199258, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-37923171

RESUMO

African Swine Fever Virus (ASFV) infection causes an acute and highly contagious disease in swine, resulting in significant economic losses and societal harm worldwide. Currently, there are no effective vaccines or antiviral drugs available for ASFV. Tetrandrine (TET) is extracted from the traditional Chinese herb Stephania tetrandrae, possesses diverse biological functions such as anti-inflammatory, anti-tumor, and antiviral activities. The study comprehensively evaluated the anti-ASFV effect of TET and validated it through biological assays. The dose-dependent inhibition of TET against ASFV was confirmed and a novel mechanism of TET's anti-ASFV activity was elucidated. TET effectively inhibits ASFV during internalization by blocking macropinocytosis through the inhibition of the PI3K/Akt pathway. The specific inhibitor LY294002, targeting the PI3K/Akt pathway, exhibits similar antiviral activity against ASFV as TET. Furthermore, the inhibitory effect of TET against other viruses such as Lumpy Skin Disease Virus (LSDV) and Porcine Epidemic Diarrhea Virus (PEDV) was also identified. Our findings suggest that TET effectively inhibits ASFV and reveal the potential for broad-spectrum antiviral drugs targeting the PI3K/Akt pathway.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Benzilisoquinolinas , Internalização do Vírus , Animais , Vírus da Febre Suína Africana/efeitos dos fármacos , Vírus da Febre Suína Africana/fisiologia , Antivirais/farmacologia , Antivirais/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Suínos , Benzilisoquinolinas/farmacologia , Internalização do Vírus/efeitos dos fármacos
5.
Chem Rev ; 123(21): 12170-12253, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37879045

RESUMO

Ionic liquids (ILs) consisting entirely of ions exhibit many fascinating and tunable properties, making them promising functional materials for a large number of energy-related applications. For example, ILs have been employed as electrolytes for electrochemical energy storage and conversion, as heat transfer fluids and phase-change materials for thermal energy transfer and storage, as solvents and/or catalysts for CO2 capture, CO2 conversion, biomass treatment and biofuel extraction, and as high-energy propellants for aerospace applications. This paper provides an extensive overview on the various energy applications of ILs and offers some thinking and viewpoints on the current challenges and emerging opportunities in each area. The basic fundamentals (structures and properties) of ILs are first introduced. Then, motivations and successful applications of ILs in the energy field are concisely outlined. Later, a detailed review of recent representative works in each area is provided. For each application, the role of ILs and their associated benefits are elaborated. Research trends and insights into the selection of ILs to achieve improved performance are analyzed as well. Challenges and future opportunities are pointed out before the paper is concluded.

6.
Tissue Cell ; 84: 102184, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37541115

RESUMO

Periodontitis is characterized by periodontal destruction triggered by chronic inflammation. The optimal treatment for periodontitis is to improve the periodontal microenvironment, reduce inflammation and achieve periodontal regeneration. Recently, the role of TRPM2 in inflammatory diseases has been reported. However, the function of TRPM2 in periodontal disease and the biological mechanism remain elusive. Therefore, this study aimed to identify the role and explore the underlying mechanisms of TRPM2 in periodontal disease. Here, we first identified the characterization of human periodontal ligament stem cells (PDLSCs). Oil Red O Staining and Alizarin Red mineralized matrix were used to evaluate the multi-differentiation capacity of cells. Flow cytometry was employed to detect MSC-specific surface markers of hPDLSCs. hPDLSCs were treated with 0, 5, 10 or 40 µg/mL of TNF-α for 72 h. Western blot assay were performed to examine the expression of Transient receptor potential cation channel, subfamily M, member 2 (TRPM2) in hPDLSCs. CCK8 and colony formation assays were used to detect the cell viability and proliferation of hPDLSCs, which revealed that TRPM2 knockdown promoted hPDLSCs proliferation. Then, ALP activity in hPDLSCs was detected by ALP activity detection kit. Next, the expression of ALP and Runx2 in hPDLSCs was detected by immunofluorescence staining. The result showed that TRPM2 knockdown promoted osteogenic differentiation and affected the genes expression of osteogenic. Finally, the expressions of p-p65, p65, p-IκBα, IκBα and NLRP3 in hPDLSCs were detected by western blot assay. Together, these results suggested that knockdown of TRPM2 accelerated osteogenic differentiation of hPDLSCs through mediating NF-κB /NLRP3 pathway.


Assuntos
Doenças Periodontais , Periodontite , Canais de Cátion TRPM , Humanos , NF-kappa B/metabolismo , Ligamento Periodontal , Inibidor de NF-kappaB alfa/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismo , Osteogênese/genética , Diferenciação Celular/genética , Periodontite/metabolismo , Inflamação/metabolismo , Doenças Periodontais/metabolismo , Células-Tronco , Células Cultivadas , Proliferação de Células
7.
J Dairy Sci ; 106(11): 7382-7395, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37641259

RESUMO

Cow milk is an important source of food protein for children; however, it could lead to allergy, especially for infants. α-Lactalbumin (α-LA) and ß-lactoglobulin (ß-LG) from whey protein make up a relatively high proportion of milk proteins and have received widespread attention as major allergens in milk. However, few studies have identified the epitopes of both proteins simultaneously. In this study, ImmunoCAP and indirect ELISA were first used for detection of sIgE to screen sera from allergic patients with high binding capacity for α-LA and ß-LG. Subsequently, the mimotopes was biopanned by phage display technology and bioinformatics and 17 mimic peptide sequences were obtained. Aligned with the sequences of α-LA or ß-LG, we identified one linear epitope on α-LA at AA 11-26 and 5 linear epitopes on ß-LG at AA 9-29, AA 45-57, AA 77-80, AA 98-101, and AA 121-135, respectively. Meanwhile, the 8 conformational epitopes and their distributions of α-LA and ß-LG were located using the Pepitope Server. Finally, glutamine and lysine were determined as common AA residues for the conformational epitopes both on α-LA and ß-LG. Moreover, we found the addition of mouse anti-human IgE during the biopanning process did not significantly affect the identification of the epitopes.

8.
Angew Chem Int Ed Engl ; 62(33): e202306971, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37327196

RESUMO

Herein, we described the first synthesis of the pentasaccharide and decasaccharide of the A. baumannii ATCC 17961 O-antigen for developing a synthetic carbohydrate-based vaccine against A. baumannii infection. The efficient synthesis of the rare sugar 2,3-diacetamido-glucuronate was achieved using our recently introduced organocatalytic glycosylation method. We found, for the first time, that long-range levulinoyl group participation via a hydrogen bond can result in a significantly improved ß-selectivity in glycosylations. This solves the stereoselectivity problem of highly branched galactose acceptors. The proposed mechanism was supported by control experiments and DFT computations. Benefiting from the long-range levulinoyl group participation strategy, the pentasaccharide donor and acceptor were obtained via an efficient [2+1+2] one-pot glycosylation method and were used for the target decasaccharide synthesis.


Assuntos
Carboidratos , Antígenos O , Antígenos O/química , Carboidratos/química , Oligossacarídeos/química , Glicosilação , Galactose
9.
Front Vet Sci ; 10: 1093733, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37256000

RESUMO

African swine fever virus (ASFV), the etiological agent of African swine fever (ASF), causes deadly hemorrhagic fever in domestic pigs. ASF's high mortality and morbidity have had disastrous effects on the world's swine industry. In recent years, the number of African swine virus strains has increased and presented new challenges for detecting classical ASFV-p72-based viruses. In this study, we observed that the ASFV MGF505-7R gene, a member of the multigene family that can enhance ASFV virulence and pathogenesis, has the potential to be a candidate for vaccine formulations. We also developed a real-time PCR assay based on the ASFV MGF505-7R gene and validated it in multiple aspects. The results indicated that the approach could detect standard plasmids with a sensitivity and a specificity of up to 1 × 101 copies/µL. Moreover, the assay had no cross-reactions with other porcine viruses. In laboratory and clinical settings, the assay can detect ASFV-infected samples at an early stage (4 hpi) and show a consistency of 92.56% when compared with classical ASFV detection in clinically ASFV-infected materials. This study's results also indicated that the TaqMan-based quantitative real-time PCR assay we developed for detecting the ASFV MGF505-7R gene is both sensitive and specific. This assay can provide a quick and accurate method for detecting ASFV and has the potential to be used as an optional tool for screening and monitoring ASF outbreaks.

10.
Vaccines (Basel) ; 11(4)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37112673

RESUMO

African swine fever (ASF) is a highly lethal and contagious disease of domestic pigs and wild boars. There is still no credible commercially available vaccine. The only existing one, issued in Vietnam, is actually used in limited quantities in limited areas, for large-scale clinical evaluation. ASF virus is a large complex virus, not inducing full neutralizing antibodies, with multiple genotypes and a lack of comprehensive research on virus infection and immunity. Since it was first reported in China in August 2018, ASF has spread rapidly across the country. To prevent, control, further purify and eradicate ASF, joint scientific and technological research on ASF vaccines has been carried out in China. In the past 4 years (2018-2022), several groups in China have been funded for the research and development of various types of ASF vaccines, achieving marked progress and reaching certain milestones. Here, we have provided a comprehensive and systematic summary of all of the relevant data regarding the current status of the development of ASF vaccines in China to provide a reference for further progress worldwide. At present, the further clinical application of the ASF vaccine still needs a lot of tests and research accumulation.

11.
J Stomatol Oral Maxillofac Surg ; 124(1S): 101383, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36646285

RESUMO

OBJECTIVE: To construct a novel portable tooth sectioning guide to improve the accuracy of mandibular third molar extraction. METHODS: First, 72 samples of an identical 3D-printed double-rooted mandibular third molar were obtained and used in 36 mandibular models. Three different models were constructed (class B vertical, mesial, and horizontal impaction). Then, we made the tooth sectioning guides. mimicking clinical tooth sectioning conditions, two dental surgeons with different levels of experience used both the digital guided technique and the traditional empirical technique during surgery. Accuracy indicators, including apical deviation and angle deviation, were analyzed and compared on postoperative cone-beam computed tomographic scanning and via image reconstruction. Descriptive statistical analyses were performed. A p-value of 0.05 indicated statistically significant differences among the groups. RESULTS: Overall, the mean apical deviation of experienced/inexperienced operators using the conventional section technique was 1.120 mm (0.7 mm, 2.3 mm) and 1.54± 0.84 mm, respectively. Correspondingly, the mean apical deviation under the guided section technique was 0.28 mm (0.2 mm, 0.4 mm) and 0.32±0.16 mm, respectively. The mean angle deviations of experienced/inexperienced operators under the conventional section technique were 8.015° (3.5°, 10.5°) and 6.570° (5.5°, 14.9°). Correspondingly, the mean apical deviation using the guided section technique was 1.880° (0.4°, 2.9°) and 1.470° (0.7°, 3.1°), respectively. The conventional and guided techniques were significantly different (P < 0.001). CONCLUSIONS: In the digital guide technique, sectioning is more predictable and accurate, and the success of the operation is achievable with different proficiencies among dental surgeons. CLINICAL SIGNIFICANCE: This technique will not only reduce the difficulty of tooth extraction but also reduce the risk of damage to the surrounding soft and hard tissues, especially damage to the inferior alveolar nerve.


Assuntos
Dente Serotino , Dente Impactado , Humanos , Dente Serotino/cirurgia , Dente Molar , Dente Impactado/cirurgia , Mandíbula/cirurgia , Extração Dentária/efeitos adversos , Extração Dentária/métodos
12.
Expert Opin Drug Saf ; 22(4): 331-338, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36178050

RESUMO

BACKGROUND: We study the adverse events (AEs) of bamlanivimab (BAM), bamlanivimab/etesevimab (BAM/ETE) to alert risk factors during coronavirus disease 2019 (COVID-19) treatment and provide references for drug safety. RESEARCH DESIGN AND METHODS: Extract AEs from the COVID-19 Emergency Use Authorization (EUA) FDA Adverse Event Reporting System (FAERS) Public Dashboard. Disproportionality analysis was performed to discover the potential risks of BAM and BAM/ETE. RESULTS: With COVID-19 drugs as the research background, the number of BAM/ETE signals is about half that of BAM, and 80% of signals overlap with BAM. Signals such as atrial fibrillation, tachycardia, and confusional state are present in BAM but not in BAM/ETE. With BAM and BAM/ETE as the research background, potential safety signals of BAM/ETE such as acute respiratory failure, hypersensitivity, and infusion-related reaction require long-term observation, especially acute respiratory failure which is not in the label. CONCLUSIONS: The AEs report on this study confirm most of the label information of BAM and BAM/ETE. BAM/ETE is relatively safe, while the risk signals such as acute respiratory failure and infusion-related reaction require to be monitored.


Assuntos
COVID-19 , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Insuficiência Respiratória , Humanos , Anticorpos Monoclonais Humanizados/efeitos adversos
13.
Front Endocrinol (Lausanne) ; 14: 1289571, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38269247

RESUMO

Background and aims: To investigate the effect of short-term very-low-calorie restriction (VLCR) on metabolism in patients with type 2 diabetes (T2D), and elucidate the molecular mechanism through analyses on gut microbiota and small-molecule metabolites. Methods: Fourteen T2D patients were hospitalized to receive VLCR (300-600 kcal/d) for 9 days. BMI, BP, and HR were taken before and after VLCR. Levels of blood lipids, fasting insulin, FBG, and 2h PBG were assessed. The microbial diversity in feces was detected by 16S rDNA high-throughput sequencing technology, and small-molecule metabolites in plasma and feces by untargeted metabolomics technology. Results: After VLCR, BW, BMI, WC, BP, and levels of FBG and 2h PBG, insulin, HOMA-IR, and triglyceride decreased significantly in T2D patients (P<0.05). There was no significant change in the α-diversity of fecal microbiota, but the abundance of Bacteroidetes increased significantly, and the Firmicutes/Bacteroidetes ratio decreased significantly from 11.79 to 4.20. Parabacteroides distasonis showed an abundance having increased most prominently after VLCR treatment. Plasma level of amino acid metabolite L-arginine increased significantly. Plasma levels of three lipid metabolites, PC (14:0/20:4 [8Z, 11Z, 14Z, 17Z]), LysoPC (16:1 [9Z]) and LysoPC (18:1 [11Z]), were significantly reduced. Fecal levels of lipid metabolite LysoPC (18:1 [11Z]) and bile acid metabolite glycholic acid were significantly decreased. Conclusion: In T2DM patients, VLCR can considerably reduce body weight and improve glucose and lipid metabolism without causing severe side effects. LysoPC (18:1 [11Z]) and Parabacteroides distasonis showed the most obvious difference after VLCR, which could be the indicators for VLCR in T2D.


Assuntos
Bacteroidetes , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Humanos , Restrição Calórica , Insulina , Lipídeos
14.
Front Microbiol ; 13: 920801, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35756009

RESUMO

Porcine epidemic diarrhoea virus (PEDV) is a member of the genus Alphacoronavirus in the family Coronaviridae. It causes acute watery diarrhoea and vomiting in piglets with high a mortality rate. Currently, the GII genotype, PEDV, possesses a high separation rate in wild strains and is usually reported in immunity failure cases, which indicates a need for a portable and sensitive detection method. Here, reverse transcription-recombinase aided amplification (RT-RAA) was combined with the Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)/Cas12a system to establish a multiplexable, rapid and portable detection platform for PEDV. The CRISPR RNA (crRNA) against Spike (S) gene of GII PEDV specifically were added into the protocol. This system is suitable for different experimental conditions, including ultra-sensitive fluorescence, visual, UV light, or flow strip detection. Moreover, it exhibits high sensitivity and specificity and can detect at least 100 copies of the target gene in each reaction. The CRISPR/Cas12a detection platform requires less time and represents a rapid, reliable and practical tool for the rapid diagnosis of GII genotype PEDV.

15.
Vet Res ; 53(1): 32, 2022 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-35461299

RESUMO

The NF-κB pathway is an essential signalling cascade in the defence against viral infections, including African swine fever virus (ASFV) infection. ASFV encodes more than 151 proteins via its own transcription machinery and possesses a great capacity to evade or subvert antiviral innate immune responses. Although some of these viral proteins have been reported, many remain unknown. Here, we show that pD345L, an ASFV-encoded lambda-like exonuclease, acts as an inhibitor of cGAS/STING-mediated NF-κB signalling by blocking the IkappaB kinase (IKKα/ß) activity. Specifically, we showed that overexpression of pD345L suppresses cGAS/STING-induced IFNß and NF-κB activation, resulting in decreased transcription of IFNß and several proinflammatory cytokines, including IL-1α, IL-6, IL-8, and TNFα. In addition, we showed that pD345L acts at or downstream of IKK and upstream of p65. Importantly, we found that pD345L associates with the KD and HLH domains of IKKα and the LZ domain of IKKß and thus interrupts their kinase activity towards the downstream substrate IκBα. Finally, we showed that pD345L-mediated inhibition of NF-κB signalling was independent of its exonuclease activity. Considering these results collectively, we concluded that pD345L blocks IKKα/ß kinase activity via protein-protein interactions and thus disrupts cGAS/STING-mediated NF-κB signalling.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Doenças dos Suínos , Vírus da Febre Suína Africana/fisiologia , Animais , Exonucleases/metabolismo , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , NF-kappa B/metabolismo , Nucleotidiltransferases/metabolismo , Suínos
16.
Chem Sci ; 13(6): 1600-1607, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35282639

RESUMO

Herein, we report a new glycosylation system for the highly efficient and stereoselective formation of glycosidic bonds using glycosyl N-phenyl trifluoroacetimidate (PTFAI) donors and a charged thiourea hydrogen-bond-donor catalyst. The glycosylation protocol features broad substrate scope, controllable stereoselectivity, good to excellent yields and exceptionally mild catalysis conditions. Benefitting from the mild reaction conditions, this new hydrogen bond-mediated glycosylation system in combination with a hydrogen bond-mediated aglycon delivery system provides a reliable method for the synthesis of challenging phenolic glycosides. In addition, a chemoselective glycosylation procedure was developed using different imidate donors (trichloroacetimidates, N-phenyl trifluoroacetimidates, N-4-nitrophenyl trifluoroacetimidates, benzoxazolyl imidates and 6-nitro-benzothiazolyl imidates) and it was applied for a trisaccharide synthesis through a novel one-pot single catalyst strategy.

17.
Transbound Emerg Dis ; 69(5): 2971-2979, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35061937

RESUMO

Genotype II African swine fever virus (ASFV) has been plaguing Chinese pig industry and caused severe morbidity and mortality of pigs resulting in huge economic losses since its first report in August 2018. Most recently, two genotype I ASFVs with low virulence but efficient transmissibility in pigs were reported in China, which makes the diagnosis and control of this lethal disease more challenging. Therefore, it is prerequisite and important to differentiate genotype I from genotype II upon ASFV outbreaks before making any stringent control procedures. In this study, a duplex real-time PCR assay based on ASFV E296R gene was established which could simultaneously detect genotypes I and II ASFVs with two pairs of primers and two probes. Plasmid containing ASFV genes was used to test the sensitivity, repeatability, and reproducibility. DNA or cDNA samples of ASFV and other swine viruses were used to test the specificity. The results showed that the established duplex real-time PCR assay has satisfied specificity, sensitivity, repeatability, and reproducibility. In addition, the assay was applied to differentiate 84 ASFV positive clinical samples including lymph nodes, spleen, kidney, lung, liver, blood, nasal swab, and environmental swab samples which were sent to National ASF Reference Laboratory from April 2020 to September 2021. The results showed that all these ASFV positive samples belong to genotype II ASFV. The established duplex real-time PCR in this study provides a powerful tool for rapid detection and differentiation between genotypes I and II ASFVs and will facilitate efficient control of ASFV in China.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Doenças dos Suínos , Febre Suína Africana/diagnóstico , Febre Suína Africana/epidemiologia , Vírus da Febre Suína Africana/genética , Animais , DNA Complementar , DNA Viral/genética , Genótipo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reprodutibilidade dos Testes , Suínos
18.
J Phys Chem A ; 125(12): 2690-2696, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33734701

RESUMO

The observed microwave effects include thermal effect, superheating or hotspots, and selective heating. These phenomena are almost impossible in classical heating, and the existence of nonthermal effect is still a controversial topic. Hotspot effect is a phenomenon that is often observed in microwave-assisted reaction and is significantly different from the traditional heating reaction. We use the quantum-state specified master equation model of microwave-assisted reaction proposed in 2016 to study the possible mechanism of microwave hotspots. We divide the hotspots into space hotspots and intramolecular hotspots, which correspond to thermal conduction and luminous behavior, respectively. For the model system in the microwave field, the microwave hotspot cannot be generated at a very low temperature of 100 K, and it is possible to generate the microwave hotspot above 300 K. Moreover, the probability of generating the microwave hotspot at 500 K is about 75 times higher than that at 350 K. The appearance of this nonlinear phenomenon is related to the uneven distribution of temperature and microwave intensity in the macroscopic level and directly related to the nonequilibrium behavior caused by microwave absorption in the quantum-state level. It is suggested that microwave hotspots can be induced by heating the given regions in the reaction vessel in advance. In addition, the formation of intramolecular hotspots can also be induced by pre-exciting the local groups in specific molecules.

19.
J Biomater Appl ; 35(7): 838-848, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32875937

RESUMO

Fibrin gel-based scaffolds have promising potential for microtia reconstruction. Autologous chondrocytes and chondrocyte cell sheets are frequently used seed cell sources for cartilage tissue engineering. However, the aesthetic outcome of chondrocyte-based microtia reconstruction is still not satisfactory. In this study, we aimed to fabricate the chondrocytes/chondrocyte-microtissues laden fibrin gel auricular scaffold for microtia reconstruction. We designed a unique auricular mold that could fabricate a fibrin gel scaffold resembling human auricle anatomy. Primary chondrocytes were harvested from rabbit auricular cartilage, and chondrocyte cell sheets were developed. Chondrocyte-microtissues were prepared from the cell sheets. The mixture of chondrocytes/chondrocyte-microtissues was laden in fibrin gel during the auricular scaffold fabrication. The protrusions and recessed structure in the auricular scaffold surface were still clearly distinguishable. After a one-week in vitro culture, the 3 D structure and auricular anatomy of the scaffold were retained. And followed by eight-week subcutaneous implantation, cartilaginous tissue was regenerated in the artificial auricular structure as indicated by the results of H&E, Toluidine blue, Safranin O, and type II collagen (immunohistochemistry) staining. Protrusions and depressions of the auricular scaffold were slightly deformed, but the overall auricular anatomy was maintained after 8-week in vivo implantation. Extracellular matrix components content were similar in artificial auricular cartilage and rabbit native auricular cartilage. In conclusion, the mixture of chondrocytes/chondrocyte-microtissues laden fibrin gel auricular scaffold showed a promising potential for cartilaginous tissue regeneration, suggesting this as an effective approach for autologous chondrocyte-based microtia reconstruction.


Assuntos
Cartilagem/fisiologia , Condrócitos/citologia , Microtia Congênita/cirurgia , Pavilhão Auricular/fisiologia , Fibrina/química , Géis/química , Engenharia Tecidual/métodos , Animais , Peso Corporal , Microtia Congênita/metabolismo , Cartilagem da Orelha/metabolismo , Matriz Extracelular/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , Coelhos , Silicones/química , Suínos , Alicerces Teciduais/química
20.
Exp Ther Med ; 19(1): 333-338, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31853308

RESUMO

The aim of the present study was to analyze the effects of methylprednisolone pulse therapy (MPPT) courses on bone metabolism in patients with Graves' ophthalmopathy (GO). A retrospective analysis of 45 patients with moderate-to-severe active GO who received 1 or 2 courses of MPPT was performed. Of these, 16 patients underwent 2 courses of treatment. Bone metabolic markers and the density of the lumbar spine (L1-4), femoral neck and total hip were measured using a dual-energy X-ray bone density instrument, and the differences in bone metabolism prior to and after treatment were determined for each group and compared. The results indicated that serum I collagen N-terminal peptide (P1NP) and serum ß-collagen crosslinked C-terminal peptide (CTX) were markedly decreased after the first pulse of treatment. In those patients who received a second course of MPPT, CTX levels were significantly decreased, but P1NP was not significantly different from the baseline value. CTX and P1NP levels remained unchanged between the first and second course of MPPT; similarly, there were no changes from baseline in 25(OH) vitamin D3 and bone mineral density after the first and second course of MPPT. However, the level of 25(OH) vitamin D3 was significantly elevated after the second course compared with the first course. In conclusion, the side effects of MPPT on bone metabolism were marginal and a second course of MPPT did not worsen bone metabolism. These MPPT regimens may therefore be considered to be a safe and effective treatment option for patients with moderate-to-severe active GO.

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