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1.
Int J Biol Macromol ; 262(Pt 1): 129998, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336326

RESUMO

How to effectively improve the poor interfacial adhesion between polylactic acid/poly(butylene adipate-co-terephthalate) (PLA/PBAT) matrix and thermoplastic starch (TPS) is still a challenge. Therefore, this work aims to introduce a convenient method to enhance the performance of PLA/PBAT/TPS blend by melt reactive extrusion. Here, using 4,4'-methylene-bis(N,N-diglycidyl-aniline) (MBDG) containing four epoxy groups as a reactive compatibilizer, and respectively using 1-methylimidazole (MI) or triethylenediamine (TD) as a catalyzer, serial PLA/PBAT/TPS ternary bio-composites are successfully prepared via melt reactive extrusion. The results showed that, under the catalysis of organic base, especially MI, the epoxy groups of MBDG can effectively react with hydroxyl and carboxyl groups of PLA/PBAT and hydroxyl groups in TPS to form chain-expanded and cross-linked structures. The tensile strength of the composites is increased by 20.0 % from 21.1 MPa, and the elongation at break is increased by 182.4 % from 17.6 % owing to the chain extension and the forming of cross-linked structures. The molecular weight, thermal stability, crystallinity, and surface hydrophobicity of the materials are gradually improved with the increase of MBDG content. The melt fluidity of the composites is also improved due to the enhancement of compatibility. The obtained PLA/PBAT/TPS materials have the potential to be green plastic products with good properties.


Assuntos
Alcenos , Resinas Epóxi , Ácidos Ftálicos , Poliésteres , Adipatos , Amido
2.
Molecules ; 28(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37570605

RESUMO

Organic thioethers play an important role in the discovery of drugs and natural products. However, the green synthesis of organic sulfide compounds remains a challenging task. The convenient and efficient synthesis of 5-alkoxy-3-halo-4-methylthio-2(5H)-furanones from DMSO is performed via the mediation of 1,3-dibromo-5,5-dimethylhydantoin (DBDMH), affording a facile route for the sulfur-functionalization of 3,4-dihalo-2(5H)-furanones under transition metal-free conditions. This new approach has demonstrated the functionalization of non-aromatic Csp2-X-type halides with unique structures containing C-X, C-O, C=O and C=C bonds. Compared with traditional synthesis methods using transition metal catalysts with ligands, this reaction has many advantages, such as the lower temperature, the shorter reaction time, the wide substrate range and good functional group tolerance. Notably, DMSO plays multiple roles, and is simultaneously used as an odorless methylthiolating reagent and safe solvent.

3.
Artigo em Inglês | MEDLINE | ID: mdl-36142084

RESUMO

The openly released and measured data from automatic hydrological and water quality stations in China provide strong data support for water environmental protection management and scientific research. However, current public data on hydrology and water quality only provide real-time data through data tables in a shared page. To excavate the supporting effect of these data on water environmental protection, this paper designs a water-quality-prediction and pollution-risk early-warning system. In this system, crawler technology was used for data collection from public real-time data. Additionally, a modified long short-term memory (LSTM) was adopted to predict the water quality and provide an early warning for pollution risks. According to geographic information technology, this system can show the process of spatial and temporal variations of hydrology and water quality in China. At the same time, the current and future water quality of important monitoring sites can be quickly evaluated and predicted, together with the pollution-risk early warning. The data collected and the water-quality-prediction technique in the system can be shared and used for supporting hydrology and in water quality research and management.


Assuntos
Monitoramento Ambiental , Qualidade da Água , China , Monitoramento Ambiental/métodos , Previsões , Hidrologia , Tecnologia
4.
Amino Acids ; 54(7): 989-999, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35305164

RESUMO

Using 3,4-dihalo-2(5H)-furanones and easily available hemostatic drugs, such as tranexamic acid (TA), 4-aminomethylbenzoic acid (ABA), aminocaproic acid (AA) as starting materials, serial multi-functional molecules 2(5H)-furanonyl amino acids are designed by the combination of different pharmacophores, and successfully synthesized by a transition metal-free Michael addition-elimination reaction. The reaction is carried out under mild conditions with ethanol-dichloromethane as solvent and only stirring at room temperature for 24 h, and the yield can be up to 91%. All products are well characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), high-resolution mass spectra (HRMS). Ten typical target compounds among them are selected out for the experiments of hemostasis performance by the evaluation of in vitro clot formation model and liver hemorrhage model. The test results show that, their hemostasis effect is better than the original drugs. Especially the target compound G, a TA derivative from 5-borneoloxy-3,4-dibromo-2(5H)-furanone, has the best hemostasis effect among all the tested compounds. These obtained target molecules are expected to be used as multi-functional hemostatic drugs.


Assuntos
Hemostáticos , Ácido Tranexâmico , Aminoácidos/farmacologia , Hemostasia , Hemostáticos/farmacologia , Ácido Tranexâmico/farmacologia
5.
iScience ; 24(6): 102518, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34142032

RESUMO

The bio-based lactic acid (LA) and the common metal ion chelating agent iminodiacetic acid (IDA) are used to design and prepare a polymeric sustained-release Pb2+ chelating agent by a brief one-step reaction. After the analysis on theoretical calculation for this reaction, poly(lactic acid-iminodiacetic acid) [P(LA-co-IDA)] with different monomer molar feed ratios is synthesized via direct melt polycondensation. P(LA-co-IDA) mainly has star-shaped structure, and some of them have two-core or three-core structure. Thus, a possible mechanism of the polymerization is proposed. The degradation rate of P(LA-co-IDA)s can reach 70% in 4 weeks. The change of IDA release rate is consistent with the trend of the degradation rate, and the good Pb2+ chelating performance is confirmed. P(LA-co-IDA) is expected to be developed as a lead poisoning treatment drug or Pb2+ adsorbent in the environment with long-lasting effect, and this research provides a new strategy for the development of such drugs.

6.
Bioorg Chem ; 107: 104518, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33303210

RESUMO

A series of (E)-N-2(5H)-furanonyl sulfonyl hydrazone derivatives have been rationally designed and efficiently synthesized by one-pot reaction with good yields for the first time. This green approach with wide substrate range and good selectivity can be achieved at room temperature in a short time in the presence of metal-free catalyst. The cytotoxic activities against three human cancer cell lines of all newly obtained compounds have been evaluated by MTT assay. Among them, compound 5 k exhibits high cytotoxic activity against MCF-7 human breast cancer cells with an IC50 value of 14.35 µM. The cytotoxic mechanism may involve G2/M phase arrest pathway, which is probably caused by activating DNA damage. Comet test and immunofluorescence results show that compound 5 k can induce DNA damage in time- and dose-dependent manner. Importantly, 5 k also can effectively inhibit the proliferation of MCF-7 cells and angiogenesis in the zebrafish xenograft model. It is potential to further develop N-2(5H)-furanonyl sulfonyl hydrazone derivatives as potent drugs for breast cancer treatment with higher cytotoxic activity by modifying the structure of the compound.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Furanos/uso terapêutico , Hidrazonas/uso terapêutico , Sulfonamidas/uso terapêutico , Inibidores da Angiogênese/síntese química , Animais , Animais Geneticamente Modificados , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/síntese química , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Hidrazonas/síntese química , Sulfonamidas/síntese química , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra
7.
J Ethnopharmacol ; 241: 111975, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31141719

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Danhong Huayu Koufuye (DHK), a compound traditional Chinese medicine, is composed of Salvia miltiorrhiza radix (Salvia miltiorrhiza Bge.), Angelicae Sinensis radix (Angelicae Sinensis (Oliv.) Diels.), Chuanxiong rhizoma (Ligusticum chuanxiong Hort.), Persicae semen (Prunus persica (L.) Batsch), Carthami flos (Carthamus tinctorius L.), Bupleuri radix (Bupleurum chinense DC.) and Aurantii fructus (Citrus aurantium L.). DHK prevents deep vein thrombosis (DVT) through antiinflammation. However, the antiinflammatory mechanism of DHK is still unknown. OBJECTIVE: The aim of this study was to evaluate whether DHK prevented venous thrombosis through antiinflammation via Sirtuin 1 (SIRT1)/NF-κB signaling pathway. METHODS: Inferior vena cava (IVC) stenosis-induced DVT rat model was established. Rats were administered with DHK (1.6, 3.2 or 6.4 mL/kg/d, p.o.), heparin (200 U/kg/d, i.v.), clopidogrel (25 mg/kg/d, p.o.), resveratrol (50 mg/kg/d, p.o.) or vehicle (p.o.) once daily for two days. Blood coagulation, blood fibrinolysis, blood viscosity, blood cell counts and platelet activity were evaluated. Serum levels of inflammatory cytokines were analyzed by enzyme-linked immunosorbent assay. Pathological changes were observed by hematoxylin-eosin (HE) staining. Protein expressions in thrombosed IVCs were evaluated by Western blot and/or immunofluorescence analyses. SIRT1 mRNA expression was analyzed by real-time quantitative polymerase chain reaction. Besides, SIRT1-specific inhibitor EX527 was pretreated to confirm the role of SIRT1/NF-κB signaling pathway in the antithrombotic effect of DHK. RESULTS: DHK remarkably prevented DVT. DHK had no effects on blood coagulation, blood fibrinolysis, blood viscosity, blood cell counts or platelet activity. But DHK significantly up-regulated protein and mRNA expressions of SIRT1, and reduced leukocytes infiltration into thrombus and vein wall, serum levels of inflammatory cytokines, and protein expressions of acetylated p65 (Ace-p65), phosphorylated p65 (p-p65) and tissue factor (TF). Moreover, the antithrombotic effect of DHK was significantly abolished by EX527. CONCLUSION: DHK may prevent DVT by inhibiting inflammation via SIRT1/NF-κB signaling pathway.


Assuntos
Anti-Inflamatórios/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Fibrinolíticos/uso terapêutico , Trombose Venosa/tratamento farmacológico , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Contagem de Células Sanguíneas , Coagulação Sanguínea/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Fibrinolíticos/química , Fibrinolíticos/farmacologia , Interleucina-1beta/sangue , Masculino , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Ativação Plaquetária/efeitos dos fármacos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/genética , Sirtuína 1/metabolismo , Fator de Necrose Tumoral alfa/sangue , Trombose Venosa/sangue , Trombose Venosa/genética , Trombose Venosa/metabolismo
8.
Org Biomol Chem ; 17(20): 5138-5147, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31073571

RESUMO

A series of amino acid derivatives are successfully synthesized via a metal-free C-N coupling reaction of 5-alkoxy-3,4-dihalo-2(5H)-furanones and amino acids. Their structures are well characterized with 1H NMR, 13C NMR, ESI-MS and elemental analysis. As potential linkers of the 2(5H)-furanone unit with other drug moieties containing a hydroxyl or amino group, the effect of amino acids is investigated by comparison with other 2(5H)-furanone compounds by constructing C-O/C-S bonds. The preliminary results of the biological activity assay by the MTT method on a series of cancer cell lines in vitro reveal that the introduction of amino acids basically has no toxic effect. This can lead to these 2(5H)-furanone derivatives being further well-linked with other bioactive moieties with amino or hydroxy groups as expected. Thus, the biological activity assay gives a direction for the design of bioactive 2(5H)-furanones based on these amino acid linkers.


Assuntos
Álcoois/farmacologia , Aminoácidos/farmacologia , Antineoplásicos/farmacologia , Furanos/farmacologia , Álcoois/química , Aminoácidos/síntese química , Aminoácidos/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/química , Humanos , Estrutura Molecular , Ratos , Relação Estrutura-Atividade
9.
Artigo em Chinês | MEDLINE | ID: mdl-22384568

RESUMO

OBJECTIVE: To investigate the maxillary sinus development and provide data for sinus surgery on children. METHOD: Two thousand two hundred and thirty-eight children were randomly selected among those who underwent skull and nasal sinus CT scanning because of certain symptoms and signs. Patients were divided into eighteen age cohorts based on their age at the time of the scan. Anterior-posterior, transverse diameters and vertical height of the maxillary sinus were measured and statistically analyzed. RESULT: The maxillary sinus volume was enlarging even in adult, hut the growth of maxillary sinus was relatively stable in adolescent. The difference of transverse and anterior-posterior diameters of maxillary sinus had no statistical significance between female and male (P > 0.05), while there was statistically significant difference in the vertical height of maxillary sinus (P < 0.05). CONCLUSION: The results will aid the physicians when correlating the clinical and radiographic findings of pediatric patients who are being evaluated for sinus disease and potential surgical intervention.


Assuntos
Seio Maxilar/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , China , Feminino , Humanos , Lactente , Masculino , Seio Maxilar/crescimento & desenvolvimento , Sinusite , Tomografia Computadorizada por Raios X , Adulto Jovem
10.
Artigo em Chinês | MEDLINE | ID: mdl-20737964

RESUMO

OBJECTIVE: To investigate the nasal sinus development and discuss the relation between sinusitis and nasal development. METHOD: One thousand seven hundred and five healthy children and 1424 children with sinusitis were selected randomly. All children underwent naso sinus computer tomography. Sagittal, coronal and transverse diameters of all sinuses were measured and statistically analyzed. RESULT: The measured sinus diameters of children with sinusitis were longer than that of healthy children (P < 0.01). Pearson analyses revealed a low correlation of age and the history of sinusitis (P < 0.01), and no correlation of gender and the history of sinusitis. There was moderate to high consistency between clinical diagnosis and nasal CT results about sinusitis (P < 0.01). CONCLUSION: These results demonstrated that the differences of sinus development exist between the healthy children and children with sinusitis, and the sinus development in children with sinusitis were better than that of healthy children.


Assuntos
Seios Paranasais/diagnóstico por imagem , Seios Paranasais/crescimento & desenvolvimento , Sinusite/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , China , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mucosa Nasal/diagnóstico por imagem , Tomografia Computadorizada por Raios X
11.
Artigo em Chinês | MEDLINE | ID: mdl-20464986

RESUMO

OBJECTIVE: In order to make a basis for the treatment of nasal sinuses of children and the correlated disease, we investigate the incidence rate of nasal sinusitis of children and explore the correlation between nasal sinusitis of children and CT in Kunming. METHOD: Two thousand one hundred and fourteen healthy children and 1535 children with sinusitis were selected randomly. Form whom were undergone nasal sinus computer tomography for different medical reasons. The incidence rates of nasal sinusitis in different age-groups were calculated and statistically analyzed. RESULT: The incidence rate of sinusitis was highest in 4 to 8 years old. There was moderate to high consistency between clinical diagnosis and nasal CT results (P<0.01). CONCLUSION: These results demonstrate that the key stage of children's sinusitis prevention would be school-age children, and nasal CT scanning is helpful to evaluate the clinical condition.


Assuntos
Sinusite/epidemiologia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Incidência , Lactente , Masculino
12.
Artigo em Chinês | MEDLINE | ID: mdl-19621598

RESUMO

OBJECTIVE: To analyze the characteristics of respiration events of sleep disordered breathing in children. METHOD: Thirty-two guide polysomnography was monitored in 203 snoring children. According to AHI and AI, they were divided into five groups and the results were analyzed by polysmith. RESULT: The mean value of REM was higher than that of NREM. The mean value between apnea and hypopnea have significant differences (P<0.01). CONCLUSION: 1) Respiration events of children mostly happen in REM. 2) The mean value of hypopnea is higher than that of apnea. 3) Diagnosing obstructive sleep apnea hypopnea syndrome in children as AI > or = 1 need research.


Assuntos
Síndromes da Apneia do Sono/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Polissonografia , Respiração , Sono REM , Ronco/fisiopatologia
13.
Artigo em Chinês | MEDLINE | ID: mdl-18720883

RESUMO

OBJECTIVE: To investigate the relationship between blood levels of lead and the function states of cochlear outer hair cells (OHC). METHOD: Two hundred and fifty-six children lived in Pb-Zn mine area and Yiliang country, aged from 6 to 7 years were enrolled in this study. Blood lead (B-Pb) levels were measured. Otoacoustic emission (OAE) tests including transient evoked otoacoustic emissions (TEOAE) and distortion products otoacoustic emission (DPOAE) were also measured in these children. RESULT: The difference in B-Pb levels between the school children who lived in mine area and children lived in country was significant (P < 0.01). There were negative correlations between the B-Pb levels and the signal to noise ratio (SNR) on DPOAE test in children who lived in country and those lived in mine area (P < 0.01). The difference in relative coefficients of B-Pb levels between the children lived in mine and children lived in country were significant (P < 0.01). CONCLUSION: The B-Pb levels of children who lived in mine area were higher than that of those lived in country. SNR decreased in plumbism cases. Long-term Pb expose may influence the function of cochlear OHC and higher B-Pb levels may lead to worse function of OHC.


Assuntos
Exposição Ambiental , Chumbo/sangue , Emissões Otoacústicas Espontâneas , Audiometria , Limiar Auditivo , Criança , Feminino , Humanos , Masculino
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