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1.
Small ; 19(11): e2206927, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36541740

RESUMO

Quasi-2D perovskites have demonstrated great application potential in light-emitting diodes (LEDs). Defect passivation with chemicals plays a critical role to achieve high efficiency. However, there are still challenges in comprehensively passivating the defects distributed at surface, bulk, and buried interface of quasi-2D perovskite emitting films, hindering the further improvement of device performance. Herein, 9,9-substituted fluorene derivatives with different terminal functional groups are developed tactfully to realize comprehensive passivation, which greatly contributes to reducing nonradiative recombination at surface, suppressing ion migration in bulk, and filling interfacial charge traps at buried interface, respectively. Eventually, quasi-2D perovskite LEDs have an increased external quantum efficiency from 18.2% to 23.2%, improved operation lifetime by more than six times and lower turn-on voltage simultaneously. Here the importance of comprehensive passivation is highlighted and guidelines for the design and application of passivators for perovskite optoelectronics are provided.

2.
BMC Pregnancy Childbirth ; 23(1): 806, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990167

RESUMO

OBJECTIVE: To explore the effect of sequential embryo transfer (ET) on the pregnancy outcome of frozen-thawed embryo transfer (FET) cycle and the indications of sequential transfer. METHODS: A total of 1440 FET cycles were enrolled in this retrospective study, of which 1080 patients received conventional ET and 360 patients received sequential ET. Further stratified analysis was performed according to the number of previous failed cycles, the number of embryos transferred and the stage of blastocyst (day 5 or 6, denoted D5 or D6) transferred. Comparison of pregnancy rates, implantation rate, miscarriage rate and multiple pregnancy rate among the groups of patients. RESULTS: The clinical pregnancy rate and implantation rate of the sequential ET group were higher than those of the conventional ET group (P < 0.01); however, there was no statistical difference in multiple pregnancy rate and miscarriage rate (P > 0.05). In sequential transfer, the number of transferred embryos (2 or 3) and the stage of transferred blastocysts (D5 or D6) had no effect on clinical pregnancy rate, implantation rate, multiple pregnancy rate and miscarriage rate (P > 0.05). In patients with three or more previous failure cycles, the sequential ET group showed higher clinical pregnancy rate and implantation rate (P > 0.05). CONCLUSIONS: Compared with conventional ET in FET cycle, sequential ET strategy could significantly improve the clinical pregnancy rate and implantation rate. In sequential transfer, patients with three embryos transferred don't have higher pregnancy rate and implantation rate. Besides, sequential transfer is more suitable for patients with repeated implantation failures (RIF), and increase the utilization rate of D6 blastocysts.


Assuntos
Aborto Espontâneo , Transferência Embrionária , Resultado da Gravidez , Feminino , Humanos , Gravidez , Aborto Espontâneo/epidemiologia , Implantação do Embrião , Resultado da Gravidez/epidemiologia , Taxa de Gravidez , Estudos Retrospectivos
3.
Microb Pathog ; 161(Pt A): 105229, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34624494

RESUMO

A new pleuromutilin derivative, 14-O-[(4,6-Diaminopyrimidine-2-yl) thioacetyl] mutilin (DPTM), has been synthesized and proven to be a potent agent against Gram-positive pathogens, especially for Staphylococcus aureus (S. aureus). However, its pharmacological activities against α-hemolysin (Hla), a major virulence factor produced by S. aureus, and inflammations related to S. aureus are still unknown. In the present study, we investigated the DPTM inhibition activities against methicillin-resistant S. aureus (MRSA) Hla and protective efficacy of Raw264.7 cells from injury induced by MRSA. The results showed that DPTM with sub-inhibitory concentrations significantly inhibited Hla on the hemolysis of rabbit erythrocytes and down-regulated the gene expressions of Hla and agrA with a dose-dependent fashion. In Raw264.7 cells infected with MRSA, DPTM efficiently attenuated the productions of lactate dehydrogenase (LDH), nitric oxide (NO) and pro-inflammatory cytokines, as well as the express levels of nuclear factor-kappaB (NF-κB), nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Furthermore, DPTM inhibited the translocation of p-65 to nucleus in RAW264.7 cells infected by MRSA.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Animais , Antibacterianos/farmacologia , Proteínas Hemolisinas , Cetonas , Resistência a Meticilina , Compostos Policíclicos , Coelhos , Staphylococcus aureus
4.
Andrologia ; 53(9): e14182, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34270116

RESUMO

The sperm quality of some males is in a critical state, making it hard for clinicians to choose the suitable fertilisation methods. This study aimed to develop an intelligent nomogram for predicting fertilisation rate of infertile males with borderline semen. 160 males underwent in vitro fertilisation (IVF), 58 of whom received rescue ICSI (R-ICSI) due to fertilisation failure (fertilisation rate of IVF ≤30%). A least absolute shrinkage and selection operator (LASSO) regression analysis identified sperm concentration, progressively motile spermatozoa (PMS), seminal plasma anti-Müllerian hormone (spAMH), seminal plasma inhibin (spINHB), serum AMH (serAMH) and serum INHB (serINHB) as significant predictors. The nomogram was plotted by multivariable logistic regression. This nomogram-illustrated model showed good discrimination, calibration and clinical value. The area under the receiver operating characteristic curve (AUC) of the nomogram was 0.762 (p < .001). Calibration curve and Hosmer-Lemeshow test (p = .5261) showed good consistency between the predictions of the nomogram and the actual observations, and decision curve analysis showed that the nomogram was clinically useful. This nomogram may be useful in predicting fertilisation rate, mainly focused on new biomarkers, INHB and AMH. It could assist clinicians and laboratory technicians select appropriate fertilisation methods (IVF or ICSI) for male patients with borderline semen.


Assuntos
Hormônio Antimülleriano , Infertilidade Masculina , Fertilização , Humanos , Infertilidade Masculina/diagnóstico , Masculino , Nomogramas , Sêmen
5.
Molecules ; 26(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071703

RESUMO

Staphylococcus aureus (S. aureus) is a major human pathogen that requires new antibiotics with unique mechanism. A new pleuromutilin derivative, 14-O-[(4,6-Diamino-pyrimidine-2-yl) thioacetyl] mutilin (DPTM), has been synthesized and proved as a potent antibacterial agent using in vitro and in vivo assays. In the present study, DPTM was further in vitro evaluated against methicillin-resistant Staphylococcus aureus (MRSA) isolated from dairy farms and outperformed tiamulin fumarate, a pleuromutilin drug used for veterinary. Moreover, a murine skin wound model caused by MRSA infection was established, and the healing effect of DPTM was investigated. The results showed that DPTM could promote the healing of MRSA skin infection, reduce the bacterial burden of infected skin MRSA and decrease the secretion of IL-6 and TNF-α inflammatory cytokines in plasma. These results provided the basis for further in-depth drug targeted studies of DPTM as a novel antibacterial agent.


Assuntos
Antibacterianos/farmacologia , Cetonas/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Compostos Policíclicos/química , Animais , Bovinos , Citocinas/metabolismo , Diterpenos/farmacologia , Desenho de Fármacos , Técnicas In Vitro , Inflamação , Interleucina-6/metabolismo , Leucócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Leite/microbiologia , Simulação de Acoplamento Molecular , Pele/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossíntese , Cicatrização , Pleuromutilinas
6.
Microb Pathog ; 127: 202-207, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30529392

RESUMO

This study assessed the antimicrobial activity of 14-O-[(4,6-Diaminopyrimidine-2-yl) thioacetyl] mutilin (DPTM), a novel pleuromutilin candidate with a substituted pyrimidine moiety, against Pasteurella multocida. Minimum Inhibitory Concentration (MIC), Oxford Cup assay, and time-kill experiments were used to measure the activity of DPTM against P. multocida serotype A in vitro. We observed that DPTM was potent against Pasteurella multocida serotype A with the MIC value of 0.781 µg/mL. The mean inhibition-zone diameters of DPTM (50, 25, and 12.5 µg/mL) were 29.4, 24.2 and 20.1 mm, respectively. Time-kill experiments showed that the drug caused a rapid decline in the number of bacteria compared with the initial inoculum at 4 h and killed 94.6% of the bacteria during 24 h. Furthermore, DPTM activity was also assessed in a lung infection model challenged with 4.0 × 109 CFU/mL P. multocida serotype A. The results showed that DPTM significantly reduced mortality rate and bacterial load, and alleviated the pathological changes of lung. The antibacterial effect of DPTM found in this study suggested that it was useful in the prevention or control of pneumonia caused by P. multocida.


Assuntos
Antibacterianos/farmacologia , Pasteurella multocida/efeitos dos fármacos , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Diterpenos/administração & dosagem , Diterpenos/química , Diterpenos/farmacologia , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Infecções por Pasteurella/tratamento farmacológico , Infecções por Pasteurella/microbiologia , Infecções por Pasteurella/patologia , Pneumonia Bacteriana/tratamento farmacológico , Pneumonia Bacteriana/microbiologia , Pneumonia Bacteriana/patologia , Compostos Policíclicos , Resultado do Tratamento , Pleuromutilinas
7.
Molecules ; 24(4)2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30813235

RESUMO

14-O-[(4,6-Diaminopyrimidine-2-yl)thioacetyl] mutilin (DPTM), a novel pleuromutilin candidate with a substituted pyrimidine moiety, has been confirmed to possess excellent antibacterial activity against Gram-positive bacteria. To illustrate the pharmacokinetic profile after intravenous (i.v.), intramuscular (i.m.) and oral (p.o.) administrations with DPTM, as well as tissue distribution and excretion via urine and feces in vivo, a specific, sensitive and robust HPLC-MS/MS method was first developed to determine DPTM in rat plasma, various tissues, urine and feces. The plasma, tissues, urine and feces samples were treated by protein precipitation with acetonitrile using tiamulin fumarate as an internal standard (IS). This method which was achieved on an HPLC system detector equipped with an ESI interface, was sensitive with 5 ng/mL as the lower limit of detection and exhibited good linearity (R² > 0.9900) in the range of 5⁻4000 ng/mL for plasma, various tissues, urine and feces, as well as intra-day precision, inter-day precision and accuracy. The matrix effects ranged from 94.2 to 109.7% with RSD ≤ 9.4% and the mean extraction recoveries ranged from 95.4 to 109.5% in plasma, tissue homogenates, urine and feces (RSD ≤ 9.9). After i.v., i.m. and p.o. administrations, DPTM was rapidly absorbed and metabolized in rats with the half-life (t1/2) of 1.70⁻1.86, 3.23⁻3.49 and 4.38⁻4.70 for 10, 25 and 75 mg/kg doses, respectively. The tissue distribution showed that DPTM was diffused into all the tested tissues, especially into the intestine and lung. Excretion via urine and feces studies demonstrated that DPTM was mainly excreted by feces after administration.


Assuntos
Líquidos Corporais/química , Fezes/química , Cetonas/administração & dosagem , Cetonas/farmacocinética , Administração Intravenosa , Administração Oral , Animais , Antibacterianos , Cromatografia Líquida de Alta Pressão , Meia-Vida , Injeções Intramusculares , Intestinos/química , Cetonas/urina , Limite de Detecção , Pulmão/química , Masculino , Compostos Policíclicos/administração & dosagem , Compostos Policíclicos/farmacocinética , Compostos Policíclicos/urina , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Distribuição Tecidual
8.
Zhongguo Zhong Yao Za Zhi ; 44(24): 5363-5367, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-32237381

RESUMO

As a natural plant source of artemisinin,a first-line drug against malaria,Artemisia annua directly affects the extraction process of artemisinin and the source of artemisinin. At present,traditional breeding methods combined with tissue culture are often used to breed high-yield artemisinin-containing new varieties of A. annua. However,the breeding method has the disadvantages of low efficiency and continuous selection. In this study,heavy ion beam irradiation technology was used to observe the specific germplasm resources of A. annua,and the morphological characteristics,agronomic traits and artemisinin content were used as indicators to observe the selection materials and materials. The cultivated new varieties were compared with trials and regional trials. In addition,the new variety of A. annua was identified by SRAP molecular marker technology. The results showed that the new variety of A. annua, " Kehao No.1",had an average yield of 235. 0 kg of dry leaf per mu,which was more than 20% higher than that of the control. Especially,the average artemisinin content was 2. 0%,which was 45% higher than that of the control,and the " Kehao No.1" has high anti-white powder disease,high-yield and high-quality new varieties. Therefore,mutagenic breeding of heavy ion beam irradiation can significantly improve the yield and artemisinin content of the " Kehao No. 1" and it has a good promotion value.


Assuntos
Artemisia annua/genética , Artemisininas/análise , Melhoramento Vegetal , Plantas Medicinais/genética , Artemisia annua/química , Íons Pesados , Mutagênese , Fenótipo , Plantas Medicinais/química
9.
Pharmacol Res ; 129: 424-431, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29133214

RESUMO

A new pleuromutilin derivative, 14-O-[(4-Amino-6-hydroxy-pyrimidine-2-yl)thioacetyl] mutilin (APTM), has been synthesized and proved most potent antibacterial agent in in vitro assays, suggesting that further development of this compound may lead to a promising antibacterial drug. In this study, we further evaluated the cytotoxicity, antibacterial efficacy and the pharmacokinetic profile of APTM. In BRL 3A cells, 50% of viability was obtained when 363µg/mL of APTM was used, while retapamulin and tiamulin fumarate needed 49 and 28µg/mL, respectively, to reach this viability. Compared to tiamulin fumarate, APTM showed higher inhibition efficacy and faster bactericidal activity against S. aureus and lower 50% effective dose (ED50) in mice after a lethal challenge with methicillin-resistant Staphylococcus aureus (MRSA). Docking experiment for APTM showed a similar binding pattern with tiamulin. Furthermore, a simple, accurate and sensitive HPLC method for the determination of APTM in rabbit plasma was developed and successfully applied to pharmacokinetic study, in which the half life (t1/2), clearance rate (Cl) and the area under the plasma concentration-time curve (AUC0→∞) were 3.37h, 0.35L/h/kg and 70.68µg·h/m, respectively.


Assuntos
Antibacterianos/farmacologia , Animais , Feminino , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Camundongos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Coelhos
10.
Arch Pharm (Weinheim) ; 351(9): e1800155, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30058185

RESUMO

Pleuromutilin derivatives 4a-h, 5a-g, and 6a-d were synthesized and characterized by IR, 1 H NMR, and 13 C NMR. All synthetic compounds were screened for their in vitro antibacterial activity against Staphylococcus aureus (ATCC 25923), methicillin-resistant S. aureus (MRSA, ATCC 43300), Pasteurella multocida (CVCC 408), Escherichia coli (ATCC 25922), and Salmonella typhimurium (ATCC 14028). Most compounds with quaternary amine showed higher antibacterial activities against both Gram-positive and Gram-negative bacteria strains. Among the screened compounds, compound 5a bearing an N,N,N-trimethyl group at the C-14 side chain of pleuromutilin was found to be the most active agent. Furthermore, preliminary molecular docking was performed to predict the binding interaction of the compounds in the binding pocket.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pasteurella multocida/efeitos dos fármacos , Salmonella typhimurium/efeitos dos fármacos , Animais , Antibacterianos/síntese química , Antibacterianos/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/síntese química , Diterpenos/química , Diterpenos/farmacologia , Relação Dose-Resposta a Droga , Escherichia coli/crescimento & desenvolvimento , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Pasteurella multocida/crescimento & desenvolvimento , Compostos Policíclicos , Ratos , Salmonella typhimurium/crescimento & desenvolvimento , Relação Estrutura-Atividade , Pleuromutilinas
11.
Molecules ; 22(6)2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28617344

RESUMO

A series of pleuromutilin derivatives were synthesized by two synthetic procedures under mild reaction conditions and characterized by Nuclear Magnetic Resonance (NMR), Infrared Spectroscopy (IR), and High Resolution Mass Spectrometer (HRMS). Most of the derivatives with heterocyclic groups at the C-14 side of pleuromutilin exhibited excellent in vitro antibacterial activities against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE), and vancomycin-resistant Enterococcus (VRE) in vitro antibacterial activity. The synthesized derivatives which contained pyrimidine rings, 3a, 3b, and 3f, displayed modest antibacterial activities. Compound 3a, the most active antibacterial agent, displayed rapid bactericidal activity and affected bacterial growth in the same manner as that of tiamulin fumarate. Moreover, molecular docking studies of 3a and lefamulin provided similar information about the interactions between the compounds and 50S ribosomal subunit. The results of the study show that pyrimidine rings should be considered in the drug design of pleuromutilin derivatives.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Simulação de Acoplamento Molecular , Antibacterianos/química , Diterpenos/química , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Compostos Policíclicos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Relação Estrutura-Atividade , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Pleuromutilinas
12.
Zhonghua Nan Ke Xue ; 23(11): 991-996, 2017 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-29738164

RESUMO

OBJECTIVE: To analyze the correlations of seminal plasma (sp) anti-Müllerian hormone (spAMH) and inhibin B (spINHB) and serum INHB (serINHB) with semen parameters in oligoasthenospermia patients and explore their value in predicting the outcome of routine in vitro fertilization (IVF). METHODS: We obtained the levels of spAMH, spINHB and serINHB as well as semen parameters from 88 infertile males undergoing IVF due to oligoasthenospermia or female uterine tubal factors from August 2016 to February 2017. Using the ROC curve and Pearson's correlation analysis, we examined the effects of the obtained parameters on the fertilization rate and assessed the correlation of the levels of spAMH, spINHB and serINHB with the semen parameters of the patients. RESULTS: Concerning the predictive value for the outcome of IVF, Pearson's correlation analysis showed that the area under the ROC curve (AUC) of spAMH was 0.807 (sensitivity = 84.6%, specificity = 76%, cut-off point = 3.529, P <0.001) and that of spINHB was 0.768 (sensitivity = 84.6%, specificity = 88.7%, cut-off point = 31.117, P = 0.002). The serINHB level was found positively correlated with sperm concentration (r = 0.346, P = 0.001), total sperm count (r = 0.378, P <0.001), sperm motility (r = 0.521, P <0.001), and the percentage of progressively motile sperm (r = 0.343, P = 0.001). CONCLUSIONS: The levels of spAMH and spINHB can be used as laboratory indexes to predict the fertilization rate of routine IVF and are correlated with semen parameters in oligoasthenospermia patients, while that of serINHB has a positive correlation with the semen parameters of the patients.


Assuntos
Hormônio Antimülleriano/análise , Astenozoospermia , Fertilização in vitro , Infertilidade Feminina , Inibinas/análise , Oligospermia , Sêmen/química , Contagem de Espermatozoides , Hormônio Antimülleriano/sangue , Feminino , Fertilização , Humanos , Inibinas/sangue , Masculino , Curva ROC , Motilidade dos Espermatozoides
13.
Microb Pathog ; 99: 247-252, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27569532

RESUMO

Avian pathogenic Escherichia coli (APEC) infections are responsible for great losses in the poultry industry. Quorum sensing (QS) acts as a global regulatory system that controls genes involved in bacterial pathogenesis, metabolism and protein biosynthesis. However, whether QS of APEC is related to cell damage has not been elucidated. In the present study, we explored the correlation between the damage of chicken type II pneumocytes induced by APEC and the autoinducer-2 (AI-2) activity of APEC. The results showed that when chicken type II pneumocytes were co-cultured with 108 CFU/ml of APEC-O78 for 6 h, the release of LDH reached the highest level (192.5 ± 13.4 U/L) (P < 0.01), and the percentages of dead cells followed the same trend in trypan blue exclusion assay. In addition, the AI-2 activity of cell-free culture fluid (CF) reached the maximum value after 6 h co-culture with 108 CFU/ml of APEC-O78. At the same time, the mRNA expressions of eight virulence genes (papC, fimA, fimC, hlyE, ompA, luxS, pfs, and qseA) of 108 CFU/ml APEC-O78 were significantly increased compared with those of 107 CFU/ml, and the mRNA expressions of four virulence genes (hlyE, tsh, iss, and luxS) of 108 CFU/ml APEC-O78 were higher than those of 109 CFU/ml (p < 0.05) after incubation for 6 h. These results suggested that AI-2-mediated QS is involved in the cell damage induced by APEC-O78, indicating AI-2 may be one new potential target for preventing chicken colibacillosis.


Assuntos
Células Epiteliais Alveolares/microbiologia , Células Epiteliais Alveolares/fisiologia , Escherichia coli/patogenicidade , Homosserina/análogos & derivados , Lactonas/metabolismo , Fatores de Virulência/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Galinhas , Técnicas de Cocultura , Escherichia coli/fisiologia , Homosserina/metabolismo , L-Lactato Desidrogenase/análise , Percepção de Quorum , Coloração e Rotulagem , Azul Tripano/análise
14.
Microb Pathog ; 99: 264-270, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27574776

RESUMO

Cinobufagin (CBG), one active ingredient isolated from Venenum Bufonis, has been demonstrated to have immunoregulatory effect. The aim of this study was to investigate whether CBG can enhance the protective efficacy of formalin-inactivated Salmonella typhimurium (FIST) in mice. ICR mice were immunized with FIST (106 CFU/mouse) alone or mixed with CBG (10, 20, and 40 µg) or alum (200 µg) on day 1 and day 15. Two weeks after the second immunization, serum and spleen were sampled for measuring FIST-specific antibody levels, cytokine levels, and splenocyte proliferation. The results showed that CBG enhanced FIST-specific IgG and IgG2a, the levels of interferon-gamma (IFNγ) and nitric oxide (NO), and the splenocyte proliferation response induced by concanavalin A, lipopolysaccharide, and FIST. In vivo protection studies showed that CBG significantly decreased the bacterial burdens in the spleen and prolonged the survival time of FIST-immunized mice challenged with live Salmonella typhimurium. In vivo IFNγ neutralization led to a significant reduction in FIST-specific IgG2a and IFNγ levels, and in the protective efficacy in CBG/FIST-immunized mice. In conclusion, CBG enhances the protective efficacy of formalin-inactivated Salmonella typhimurium vaccine by promoting the Th1 immune response.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Bufanolídeos/administração & dosagem , Vacinas contra Salmonella/imunologia , Salmonella typhimurium/imunologia , Células Th1/imunologia , Compostos de Alúmen/administração & dosagem , Animais , Anticorpos Antibacterianos/sangue , Proliferação de Células , Citocinas/análise , Modelos Animais de Doenças , Fixadores , Formaldeído , Esquemas de Imunização , Imunoglobulina G/sangue , Leucócitos Mononucleares/imunologia , Camundongos Endogâmicos ICR , Salmonelose Animal , Vacinas contra Salmonella/administração & dosagem , Soro/imunologia , Baço/imunologia , Baço/microbiologia , Análise de Sobrevida , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia
15.
ACS Appl Mater Interfaces ; 15(8): 10877-10884, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36795030

RESUMO

The introduction of additives has become an important method for enhancing the device performance of quasi-two-dimensional perovskite light-emitting diodes. In this work, we systematically studied the electronic and spatial effects of molecular additives on defect passivation abilities using the methyl, hydrogen, and hydroxyl groups substituted three diphenyl phosphine oxygen additives. The electron-donating conjugation effect of the hydroxyl group on diphenylphosphinic acid (OH-DPPO) leads to a more electron-rich region in OH-DPPO, and the hydroxyl group has a moderate steric hindrance. All these factors endow it with best passivation ability than the other two additives. Furthermore, ion migration was suppressed due to hydrogen bonding between the hydroxyl group and Br. Ultimately, the OH-DPPO passivated devices achieved an external quantum efficiency of 22.44% and a 6-fold improvement in lifetime. These findings provide guidance for developing multifunctional additives in the field of perovskite optoelectronics.

16.
BMC Pharmacol Toxicol ; 23(1): 2, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983673

RESUMO

BACKGROUND: Py-mulin is a new pleuromutilin derivative with potent antibacterial activities in vitro and in vivo, suggesting this compound may lead to a promising antibacterial drug after further development. The present study is aimed to evaluate the acute and subacute oral toxicity, and the genotoxicity with the standard Ames test according to standard protocols. METHODS: Acute oral toxicity of Py-mulin was determined using Kunming mice. The 28-day repeated dose oral toxicity study in SD rats was performed according to OECD guideline No. 407. The bacterial reverse mutation (Ames test) was carried out using four Salmonella typhimurium (S. typhimurium) strains TA97, TA98, TA100 and TA1535 with and without S9 metabolic activation. RESULTS: The LD50 values in acute oral toxicity were 2973 mg/kg (female mice) and 3891 mg/kg (male mice) calculated by the Bliss method. In subacute toxicity study, 50 mg/kg Py-mulin did not induce any abnormality in body weight, food consumption, clinical sign, hematology, clinical chemistry, organ weight, and histopathology in all of the treatment groups. However, high doses of Py-mulin (100 and 300 mg/kg) displayed slightly hepatotoxicity to female rats. Furthermore, Py-mulin did not significantly increase the number of revertant colonies of four standard S. typhimurium strains with the doses of 0.16-1000 µg/plate in the Ames study. CONCLUSIONS: Based on our findings, our study provides some information for the safety profile of Py-mulin.


Assuntos
Antibacterianos , Salmonella typhimurium , Animais , Antibacterianos/toxicidade , Feminino , Dose Letal Mediana , Masculino , Camundongos , Testes de Mutagenicidade/métodos , Ratos , Ratos Sprague-Dawley , Salmonella typhimurium/genética
17.
Light Sci Appl ; 11(1): 69, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35322007

RESUMO

Emission thermal quenching is commonly observed in quasi-2D perovskite emitters, which causes the severe drop in luminescence efficiency for the quasi-2D perovskite light-emitting diodes (PeLEDs) during practical operations. However, this issue is often neglected and rarely studied, and the root cause of the thermal quenching has not been completely revealed now. Here, we develop a passivation strategy via the 2,7-dibromo-9,9-bis (3'-diethoxylphosphorylpropyl)-fluorene to investigate and suppress the thermal quenching. The agent can effectively passivate coordination-unsaturated Pb2+ defects of both surface and bulk of the film without affecting the perovskite crystallization, which helps to more truly demonstrate the important role of defects in thermal quenching. And our results reveal the root cause that the quenching will be strengthened by the defect-promoted exciton-phonon coupling. Ultimately, the PeLEDs with defect passivation achieve an improved external quantum efficiency (EQE) over 22% and doubled operation lifetime at room temperature, and can maintain about 85% of the initial EQE at 85 °C, much higher than 17% of the control device. These findings provide an important basis for fabricating practical PeLEDs for lighting and displays.

18.
Front Microbiol ; 13: 1100988, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36726569

RESUMO

Heavy metals released in the environment pose a huge threat to soil and water quality, food safety and public health. Additionally, humans and other mammals may also be directly exposed to heavy metals or exposed to heavy metals through the food chain, which seriously threatens the health of animals and humans. Chromium, especially hexavalent chromium [Cr (VI)], as a common heavy metal, has been shown to cause serious environmental pollution as well as intestinal damage. Thus, increasing research is devoted to finding drugs to mitigate the negative health effects of hexavalent chromium exposure. Seaweed polysaccharides have been demonstrated to have many pharmacological effects, but whether it can alleviate gut microbial dysbiosis caused by hexavalent chromium exposure has not been well characterized. Here, we hypothesized that seaweed polysaccharides could alleviate hexavalent chromium exposure-induced poor health in mice. Mice in Cr and seaweed polysaccharide treatment group was compulsively receive K2Cr2O7. At the end of the experiment, all mice were euthanized, and colon contents were collected for DNA sequencing analysis. Results showed that seaweed polysaccharide administration can restore the gut microbial dysbiosis and the reduction of gut microbial diversity caused by hexavalent chromium exposure in mice. Hexavalent chromium exposure also caused significant changes in the gut microbial composition of mice, including an increase in some pathogenic bacteria and a decrease in beneficial bacteria. However, seaweed polysaccharides administration could ameliorate the composition of gut microbiota. In conclusion, this study showed that seaweed polysaccharides can restore the negative effects of hexavalent chromium exposure in mice, including gut microbial dysbiosis. Meanwhile, this research also lays the foundation for the application of seaweed polysaccharides.

19.
Stem Cell Res Ther ; 12(1): 161, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658073

RESUMO

Premature ovarian failure (POF) is one of the common disorders found in women leading to 1% female infertility. Clinical features of POF are hypoestrogenism or estrogen deficiency, increased gonadotropin level, and, most importantly, amenorrhea. With the development of regenerative medicine, human mesenchymal stem cell (hMSC) therapy brings new prospects for POF. This study aimed to describe the types of MSCs currently available for POF therapy, their biological characteristics, and their mechanism of action. It reviewed the latest findings on POF to provide the theoretical basis for further investigation and clinical therapy.


Assuntos
Células-Tronco Mesenquimais , Insuficiência Ovariana Primária , Feminino , Humanos , Fatores Imunológicos , Masculino , Insuficiência Ovariana Primária/terapia , Medicina Regenerativa
20.
J Phys Chem Lett ; 12(48): 11645-11651, 2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34822249

RESUMO

Solution-processed quasi-two-dimensional (quasi-2D) perovskites with self-assembled multiple quantum well (QW) structures exhibit enhanced exciton binding energy, which is ideal for use as light emitters. Here, we have found that postannealing is important to promoting the QWs' composition transfer, and we explored the correlation among the annealing time, the external quantum efficiency (EQE), and the operational stability of the device. During thermal annealing, the low-n QWs will gradually convert to high-n phases, accompanied by an increase in grain size. The EQE and working stability of the device exhibit different annealing-time dependences; that is, with the extension of the annealing time, the EQE gradually decreases while the working stability improves. By introducing trimethylolpropane trimethacrylate (TPTA) to passivate the emitting-region defects, the annealing-time dependence of the EQE was effectively eliminated due to the reduction of the nonradiative recombination rate, wherefore high efficiency and stability can be achieved simultaneously. Our research provides an effective way to develop highly efficiency and stable perovskite light-emitting diodes.

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