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1.
PLoS Comput Biol ; 19(9): e1011383, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37656752

RESUMO

Once challenged by the SARS-CoV-2 virus, the human host immune system triggers a dynamic process against infection. We constructed a mathematical model to describe host innate and adaptive immune response to viral challenge. Based on the dynamic properties of viral load and immune response, we classified the resulting dynamics into four modes, reflecting increasing severity of COVID-19 disease. We found the numerical product of immune system's ability to clear the virus and to kill the infected cells, namely immune efficacy, to be predictive of disease severity. We also investigated vaccine-induced protection against SARS-CoV-2 infection. Results suggested that immune efficacy based on memory T cells and neutralizing antibody titers could be used to predict population vaccine protection rates. Finally, we analyzed infection dynamics of SARS-CoV-2 variants within the construct of our mathematical model. Overall, our results provide a systematic framework for understanding the dynamics of host response upon challenge by SARS-CoV-2 infection, and this framework can be used to predict vaccine protection and perform clinical diagnosis.


Assuntos
COVID-19 , Viroses , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Carga Viral
2.
BMC Anesthesiol ; 23(1): 298, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667179

RESUMO

PURPOSE: Transfusing red blood cells promptly corrects anemia and improves tissue oxygenation in around 40% of patients hospitalized in the intensive care unit (ICU) after major surgical operations. This study's goal is to investigate how blood transfusions affect the mortality rates of patients after major surgery who are hospitalized in the ICU. METHODS: Retrospective research was done on recently hospitalized patients who had major procedures in the ICU between October 2020 and February 2022 at the Huanggang Central Hospital of Yangtze University, China. The patients' prognoses at three months were used to classify them as either survivors or deceased. Patient demographic information, laboratory results, and blood transfusion histories were acquired, and the outcomes of the two groups were compared based on the differences. Univariate and multivariate logistic regression analyses were used to examine the prognosis of surgical disease patients first admitted to the ICU. The receiver operating characteristic (ROC) curve was used to evaluate the predictive power of each risk factor. The relationship between transfusion frequency, transfusion modality, and patient outcome was examined using Spearman's correlation analysis. RESULTS: Data from 384 patients was included in the research; of them, 214 (or 55.7%) died within three months of their first stay in the ICU. The death group had higher scores on the Acute Physiology and Chronic Health Evaluation II (APACHE II) and the Sequential Organ Failure Assessment (SOFA) than the survival group did (all P < 0.05); the death group also had lower scores on the Glasgow Coma Scale, systolic blood pressure, hemoglobin, platelet distribution width, and blood transfusion ratio. Multivariate logistic regression analysis revealed an odds ratio (OR) of 1.654 (1.281-1.989), a 95% confidence interval (CI) of 1.440 (1.207-1.701), and a P value of 0.05 for death in patients undergoing major surgery who were hospitalized to the intensive care unit (ICU). Areas under the ROC curve (AUC) of 0.836, 0.799, and 0.871, respectively, and 95% CIs of 0.796-0.875, 0.755-0.842, and 0.837-0.904, respectively, all P0.05, had significant predictive value for patients initially admitted to the ICU and for APACHE II score > = 12 points, SOFA score > = 6, and blood transfusion. When all three indicators were used jointly to predict a patient's prognosis after major surgery, the accuracy increased to 86.4% (sensitivity) and 100% (specificity). There was a negative correlation between the number of blood transfusions a patient had and their outcome (r = 0.605, P < 0.001) and death (r = 0.698, P < 0.001). CONCLUSION: A higher initial ICU APACHE II score, SOFA score, and a number of blood transfusions were associated with improved survival for patients undergoing major surgical operations. Patients' death rates have increased with the increase in the frequency and variety of blood transfusions.


Assuntos
Hospitalização , Hospitais , Humanos , Estudos Retrospectivos , Transfusão de Sangue , Unidades de Terapia Intensiva
3.
Theor Appl Genet ; 135(8): 2861-2873, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35819492

RESUMO

KEY MESSAGE: The powdery mildew resistance locus was mapped to A. cristatum chromosome 6PL bin (0.27-0.51) and agronomic traits evaluation indicated that this locus has potential breeding application value. Agropyron cristatum (2n = 4x = 28, PPPP) is a wild relative of wheat with an abundance of biotic and abiotic stress resistance genes and is considered one of the best exogenous donor relatives for wheat breeding. A number of wheat-A. cristatum derived lines have been generated, including addition lines, translocation lines and deletion lines. In this study, the 6P disomic addition line 4844-12 (2n = 2x = 44) was confirmed to have genetic effects on powdery mildew resistance. Four 6P deletion lines (del16a, del19b, del21 and del27) and two translocation lines (WAT638a and WAT638b), derived from radiation treatment of 4844-12, were used to further assess the 6P powdery mildew resistance locus by powdery mildew resistance assessment, genomic in situ hybridization (GISH), fluorescence in situ hybridization (FISH) and 6P specific sequence-tagged-site (STS) markers. Collectively, the locus harboring the powdery mildew resistance gene was genetically mapped to a 6PL bin (0.27-0.51). The genetic effects of this chromosome segment on resistance to powdery mildew were further confirmed by del16a and del27 BC3F2 lines. Comprehensive evaluation of agronomic traits revealed that the powdery mildew resistance locus of 6PL (0.27-0.51) has potential application value in wheat breeding. A total of 22 resistant genes were annotated and 3 specific gene markers were developed for detecting chromatin of the resistant region based on genome re-sequencing. In summary, this study could broaden the powdery mildew resistance gene pool for wheat genetic improvements.


Assuntos
Agropyron , Agropyron/genética , Cromossomos de Plantas/genética , Resistência à Doença/genética , Hibridização in Situ Fluorescente , Melhoramento Vegetal , Doenças das Plantas/genética , Translocação Genética , Triticum/genética
4.
Biomacromolecules ; 23(10): 4153-4166, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35786865

RESUMO

Polyhydroxyalkanoates (PHAs) are microbial polyesters that have the potential to replace nonbiodegradable petroplastics. A real-time in situ PHA quantification method has long been awaited to replace the traditional method, which is time- and labor-consuming. Quantification of PHA in living cells was finally developed from fluorescence intensities generated from the green fluorescence protein (GFP) fused with the Halomonas bluephagenesis phasin proteins. Phasins PhaP1 and PhaP2 were used to fuse with GFP, which reflected PHA accumulation with an R-square of over 0.9. Also, a standard correlation was established to calculate PHA contents based on the fluorescence and cell density recorded via a microplate reader with an R-square of over 0.95 when grown on various substrates. The PhaP2-GFP containing H. bluephagenesis was applied successfully to quantify PHA synthesis in a 7.5 L fermenter with high precision. Moreover, the method was found to be feasible in non-natural PHA producers such as Escherichia coli, demonstrating its broad applicability.


Assuntos
Poli-Hidroxialcanoatos , Proteínas de Bactérias/química , Escherichia coli/genética , Escherichia coli/metabolismo , Fluorescência , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Lectinas de Plantas , Poliésteres/metabolismo , Poli-Hidroxialcanoatos/metabolismo
5.
J Clin Lab Anal ; 34(9): e23415, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32488958

RESUMO

BACKGROUND: This study aimed to investigate clinical characteristics, laboratory indexes, treatment regimens, and short-term outcomes of severe and critical coronavirus disease 2019 (COVID-19) patients. METHODS: One hundred and sixty one consecutive severe and critical COVID-19 patients admitted in intensive care unit (ICU) were retrospectively reviewed in this multicenter study. Demographic features, medical histories, clinical symptoms, lung computerized tomography (CT) findings, and laboratory indexes on admission were collected. Post-admission complications, treatment regimens, and clinical outcomes were also documented. RESULTS: The mean age was 59.38 ± 16.54 years, with 104 (64.60%) males and 57 (35.40%) females. Hypertension (44 [27.33%]) and diabetes were the most common medical histories. Fever (127 [78.88%]) and dry cough (111 [68.94%]) were the most common symptoms. Blood routine indexes, hepatic and renal function indexes, and inflammation indexes were commonly abnormal. Acute respiratory distress syndrome (ARDS) was the most common post-admission complication (69 [42.86%]), followed by electrolyte disorders (48 [29.81%]), multiple organ dysfunction (MODS) (37 [22.98%]), and hypoproteinemia (36 [22.36%]). The most commonly used antiviral drug was lopinavir/ritonavir tablet. 50 (31.06%) patients died, while 78 (48.45%) patients healed and discharged, and the last 33 (20.50%) patients remained in hospital. Besides, the mean hospital stay of deaths was 21.66 ± 11.18 days, while the mean hospital stay of discharged patients was 18.42 ± 12.77 days. Furthermore, ARDS (P < .001) and MODS (P = .008) correlated with increased mortality rate. CONCLUSION: Severe and critical COVID-19 presents with high mortality rate, and occurrence of ARDS or MODS greatly increases its mortality risk.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/terapia , Pneumonia Viral/patologia , Pneumonia Viral/terapia , Índice de Gravidade de Doença , Adulto , Fatores Etários , Idoso , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/mortalidade , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/mortalidade , SARS-CoV-2 , Resultado do Tratamento
6.
J Mater Sci Mater Med ; 29(5): 47, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-29687339

RESUMO

L-Leucine (Leu) is a hydrophobic natural amino acid and can polymerize into poly-L-Leucine (PLeu) to be an excellent biocompatible material. In this paper, a hyperbranched copolymer polyethyleneimine-g-poly-L-leucine (PEI-g-PLeu) was synthesized by ring-opening polymerization with leucine NCA as monomer and PEI as initiator, which will be used as drug and gene co-delivery system for cancer therapy. To characterize the transfection efficiency in vitro, pGL3 as the reporter gene was loaded in PEI-g-PLeu to form complexes. Doxorubicin (DOX) with cis-aconitic anhydride linker (CAD) and calf thymus DNA (as model DNA) were co-loaded in PEI-g-PLeu to obtain PEI-g-PLeu/DNA/CAD nanoparticles to measure Zeta potentials and particle sizes. Lastly, CAD and modified Bc12-shRNA(as therapeutic gene) were co-loaded in PEI-g-PLeu to get PEI-g-PLeu/CAD/DNA complexes. Our finding revealed when PEI and PLeu with the molar ratio of 1:240, and PEI-g-PLeu and DNA with the mass ratio of 1:5, PEI-g-PLeu/CAD/DNA had negligible cytotoxicity with equivalent gene transfaction efficiency compared with PEI25k. As a result, PEI-g-PLeu/CAD/DNA was a promising drug and gene co-delivery system.


Assuntos
Materiais Biocompatíveis/síntese química , Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Peptídeos/química , Polietilenoimina/química , Polímeros/síntese química , Animais , Materiais Biocompatíveis/química , Células Cultivadas , DNA/administração & dosagem , DNA/farmacocinética , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Iminas/química , Teste de Materiais , Camundongos , Tamanho da Partícula , Polietilenoimina/síntese química , Polietilenos/química , Polímeros/química , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/farmacocinética , Transfecção
7.
Molecules ; 21(7)2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27347912

RESUMO

In order to discover novel eco-friendly compounds with good activity for aphid control, (E)-ß-farnesene (EßF), the main component of the aphid alarm pheromone, was chosen as the lead compound. By introducing a 2-nitroimino-hexahydro-1,3,5-triazine moiety (abbreviated NHT) to replace the unstable conjugated double bond system of EßF, a series of novel EßF analogues containing the NHT moiety were synthesized via the reaction of substituted NHT rings with (E)-1-chloro-3,7-dimethylocta-2,6-diene. All the compounds were characterized by ¹H-NMR, (13)C-NMR, IR, and high resolution mass spectroscopy (HRMS). The bioassay results showed that all the analogues displayed different repellent and aphicidal activities against green peach aphid (Myzus persicae). Particularly, the analogue 4r exhibited obvious repellent activity (repellent proportion: 78.43%) and similar aphicidal activity against M. persicae (mortality: 82.05%) as the commercial compound pymetrozine (80.07%). A preliminary structure-activity relationship (SAR) study was also performed, which offered valuable clues for the design of further new EßF analogues.


Assuntos
Sesquiterpenos/síntese química , Sesquiterpenos/farmacologia , Triazinas/química , Animais , Afídeos/efeitos dos fármacos , Desenho de Fármacos , Repelentes de Insetos/química , Repelentes de Insetos/farmacologia , Modelos Moleculares , Estrutura Molecular , Sesquiterpenos/química , Relação Estrutura-Atividade
8.
Small ; 11(34): 4321-33, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26136261

RESUMO

A pulmonary codelivery system that can simultaneously deliver doxorubicin (DOX) and Bcl2 siRNA to the lungs provides a promising local treatment strategy for lung cancers. In this study, DOX is conjugated onto polyethylenimine (PEI) by using cis-aconitic anhydride (CA, a pH-sensitive linker) to obtain PEI-CA-DOX conjugates. The PEI-CA-DOX/siRNA complex nanoparticles are formed spontaneously via electrostatic interaction between cationic PEI-CA-DOX and anionic siRNA. The drug release experiment shows that DOX releases faster at acidic pH than at pH 7.4. Moreover, PEI-CA-DOX/Bcl2 siRNA complex nanoparticles show higher cytotoxicity and apoptosis induction in B16F10 cells than those treated with either DOX or Bcl2 siRNA alone. When the codelivery systems are directly sprayed into the lungs of B16F10 melanoma-bearing mice, the PEI-CA-DOX/Bcl2 siRNA complex nanoparticles exhibit enhanced antitumor efficacy compared with the single delivery of DOX or Bcl2 siRNA. Compared with systemic delivery, most drug and siRNA show a long-term retention in the lungs via pulmonary delivery, and a considerable number of the drug and siRNA accumulate in tumor tissues of lungs, but rarely in normal lung tissues. The PEI-CA-DOX/Bcl2 siRNA complex nanoparticles are promising for the treatment of metastatic lung cancer by pulmonary delivery with low side effects on the normal tissues.


Assuntos
Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/química , RNA Interferente Pequeno/metabolismo , Anidridos/síntese química , Anidridos/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/farmacologia , Endocitose/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Espaço Intracelular/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos C57BL , Metástase Neoplásica , Tamanho do Órgão/efeitos dos fármacos , Tamanho da Partícula , Polietilenoimina/síntese química , Polietilenoimina/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Eletricidade Estática , Distribuição Tecidual/efeitos dos fármacos
9.
Sci Total Environ ; 935: 173401, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38782269

RESUMO

Knowing the sources of precipitation chemical composition is essential to understand the biogeochemical cycle and control air pollution. Despite this issue has been directly investigated with precipitation ion contents, the effects of water vapor transport have not been fully considered. Taking the Loess Plateau of China (LPC) as an example study area, this study established nine precipitation monitoring sites considering the variability in topography and rainfall amounts, and collected 435 precipitation samples during 2020-2022 to measure the chemical composition. The correlation analysis, positive matrix factorization model and backward trajectory model were combined to analyze the characteristics, sources and vapor transport effects of precipitation chemical composition. Seasonally, except for NH4+, the concentration of other ions in the dry season was significantly higher than that in the rainy season. Spatially, the concentrations of Ca2+, Na+, K+, SO42- and NO3- peaked in the Mu Us Sandy Land and industrial areas, while the high level of NH4+ was concentrated in the agricultural areas. The source apportionment found that the primary source of precipitation ions was crust (33 %), followed by coal combustion/vehicle (30 %), aged sea salt (21 %) and agriculture (16 %). The trajectory analysis showed that water vapor paths significantly varied with the seasons, but were primarily dominated by the northwestern air mass with proportions of >40 %. The dust aerosols transported by the northwestern air mass were the main contributor to crust-source precipitation ions. The eastern and southeastern air masses transported anthropogenic pollutants to the LPC, and the southeastern air mass also carried sea-salt precipitation ions. This study provides a framework to incorporate hydrochemical method with vapor source identification method for precipitation chemical source identification, and the results can be a theoretical basis for the treatment of atmospheric environmental problems.

10.
J Phys Chem B ; 127(18): 4145-4153, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37130439

RESUMO

There is growing evidence showing that many critical biological processes are driven by biomolecule condensates through liquid-liquid phase separation (LLPS). Although the qualitative observation and description of LLPS have been well documented, quantitative simulations of the time-dependent progression of LLPS in live cells are generally lacking. In this work, we build a stochastic Monte Carlo model to simulate the dynamic LLPS process during the formation of bacterial aggresomes. We demonstrate that the size distribution of the protein condensates evolves from an exponential-like to a bimodal-like pattern, and the number of condensates increases at the beginning and then decreases after reaching a maximum. Incorporating diffusion and collision, our simplified model recapitulates the two-step LLPS process in which many smaller condensates are formed in the first step and then merged into a few larger ones. We further reveal that the condensation speed, which can be defined by the condensates formed in unit time during the first step, is mainly determined by both the collision energy barrier and the initial protein density, while the number of condensates at the equilibrium is mainly associated with the dissociation energy barrier. Moreover, the LLPS process is not sensitive to temperature changes ranging around physiological conditions. Additionally, we consider the effect of the nucleation energy barrier on LLPS. We find that a higher nucleation energy barrier brings a slower condensation speed. Overall, we simulate the spatiotemporal dynamics of the LLPS process and provide qualitative guidance for understanding the dynamics of LLPS in bacterial cells, which can faithfully recapitulate experimental observations and facilitate the design of future experimental tests.


Assuntos
Bactérias , Proteínas , Bactérias/citologia
11.
Diagn Microbiol Infect Dis ; 107(4): 116081, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37801886

RESUMO

BACKGROUND: The purpose of this study was to develop a 1-step real-time quantitative fluorescence polymerase chain reaction (QF-PCR) method for detecting Bovine Group A Rotavirus (BRVA). The primers and probe were designed targeting the VP6 gene of BRVA. The standard substance was obtained through in vitro transcription. The primers, probe concentration, and annealing temperatures were optimized to determine the optimal system and conditions for the reaction. The specificity, sensitivity, and repeatability of the method were assessed and compared with a reported real-time QF-PCR method for clinical samples. RESULTS: The results indicated that the detection method can achieve a sensitivity of 3.47 copies/µL and exhibit good specificity by exclusively detecting BRVA without cross-reactivity to other common pathogens in cattle and sheep. The standard curve exhibited a robust linear correlation, and the amplification efficiency was calculated to be 105%. The intra-group and inter-group coefficients of variation were less than 2%. A total of 96 clinical samples were tested and compared with the real-time QF-PCR method that was reported. The coincidence rate was 90.63% (87/96). Furthermore, the clinical samples revealed that the prevalence of BRV in cattle from Fujian Province was 85.42% (82/96). CONCLUSION: This study has successfully developed a 1-step real-time QF-PCR method for BRVA, which offers an efficient and sensitive technical support for the rapid diagnosis and epidemiological investigation of BRVA.


Assuntos
Rotavirus , Animais , Bovinos , Ovinos/genética , Rotavirus/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Primers do DNA
12.
Materials (Basel) ; 15(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35744180

RESUMO

Surface cracking is a major issue in amino resin-based flame-retardant coatings, which can be reduced by mixing flexible resins into the coatings. In this study, flexible waterborne polyurethane (WPU) was added into a melamine-modified, urea-formaldehyde, resin-based intumescent flame retardant (MUF-IFR) coating. A molecular chain of WPU was inserted into the MUF network and formed a WPU/MUF-semi-IPN structure. The cracking resistance of the coating was gradually enhanced with the increase in WPU content. When the WPU content exceeded 25% of the total resin, there were no cracks in the coatings after crack-resistance tests. The coatings before and after toughening showed good transparency on wood surfaces. The influence of WPU on char formation and flame retardant properties were explored by TGA, SEM, and cone calorimetry. The results showed that the decomposition of WPU occurred before char formation, which decreased the integrity of the coating and damaged the compactness of the char. Therefore, the addition of WPU reduced the expansion height and the barrier capacity of the char as well as the flame retardant properties of the coating. When the amount of WPU was 25% of the total resin, compared to the non-WPU coating, the average heat release rate in 300 s (AveHRR300s) and the total heat release at 300 s (THR300s) of the samples were increased by 45.8% and 35.7%, respectively. However, compared to the naked wood, the peak heat release rate (pHRR1), AveHRR300s, and THR300s of the samples with the coating containing 25% WPU were decreased by 64.2%, 39.0%, and 39.7%, respectively. Therefore, the thermal stability of WPU affected char formation. The amount of WPU added should be chosen to be the amount that was added just before the coating cracked.

13.
Polymers (Basel) ; 14(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36365524

RESUMO

The thermal degradation kinetics and degradation products of IPBC during the heating process are investigated herein. Experiments were conducted at isothermal conditions from 60 °C to 150 °C. The remaining IPBC content was analyzed by high-performance liquid chromatography (HPLC) at specific time intervals for each test, and the kinetic model of IPBC thermal degradation was established. The thermal degradation products of IPBC were studied by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS). The results showed that thermal degradation of IPBC occurred at 70 °C, and the degradation rate increased significantly from 70 °C to 150 °C. The thermal degradation kinetics of IPBC conformed to the first-order reaction and k=3.47×1012e-111125/RT from 60 °C to 150 °C. Seven degradation products such as prop-2-yn-1-yl ethylcarbamate and methyl N-butylcarbamate were identified and the degradation reaction pathway and the mechanism of IPBC were proposed, which involved deiodination, demethylation, deethynylation, deethylation, and hydroxylation processes.

14.
Polymers (Basel) ; 14(24)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36559904

RESUMO

Bamboo is rich in starch and sugars and can be infected by mold and stain fungi, degrading its performance, shortening its service life, and reducing its utilization value. It is crucial to investigate how to protect bamboo against mold and stain fungi. The zone of inhibition test was used to evaluate the antifungal activity of azoxystrobin, kresoxim-methyl, pyraclostrobin and 3-iodo-2-propynyl-butylcarbamate (IPBC) against stain fungi (Botryodiplodia theobromae, Fusarium moniliforme, and Alternaria alternate) and mold fungi (Aspergillus niger, Penicillium citrinum, and Trichoderma viride) to develop new chemicals to protect bamboo against stain fungi and molds. The inhibitory activity of the composite pyraclostrobin and IPBC with different ratios was evaluated. Water-based formulations of the fungi were used to treat the bamboo, and the mold and stain resistance of the bamboo was investigated at different chemical retention rates. The results showed that the antifungal activity of pyraclostrobin was significantly higher than that of azoxystrobin and kresoxim-methyl. Different degrees of inhibitory activities against the stain and mold fungi were observed, and the inhibitory activity was higher against stain fungi than against molds. The three stain fungi were completely inhibited at a 7:3 ratio of pyraclostrobin to IPBC and 0.1% concentration. As the ratio increased, the inhibitory effect against mixed mold strains improved. The control efficacy of the pyraclostrobin formulations Str-1 and Str-2 at 0.1% concentration was 100% against Alternaria alternate and 70.8% against Fusarium moniliforme. The control efficacy of the composite formulations SI-1 and SI-2 at 0.1% concentration was 100% against all three stain fungi and greater than 91.8% against the mixed mold strains. This study provides new insights into the utilization of pyraclostrobin and its composite formulations as new bamboo antifungal agents.

15.
Heliyon ; 8(5): e09488, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35600458

RESUMO

The determinants underlying the heterogeneity of coronavirus disease 2019 (COVID-19) remain to be elucidated. To systemically analyze the immunopathogenesis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, we built a multicompartment mathematical model based on immunological principles and typical COVID-19-related characteristics. This model integrated the trafficking of immune cells and cytokines among the secondary lymphoid organs, peripheral blood and lungs. Our results suggested that early-stage lymphopenia was related to lymphocyte chemotaxis, while prolonged lymphopenia in critically ill patients was associated with myeloid-derived suppressor cells. Furthermore, our model predicted that insufficient SARS-CoV-2-specific naïve T/B cell pools and ineffective activation of antigen-presenting cells (APCs) would cause delayed immunity activation, resulting in elevated viral load, low immunoglobulin level, etc. Overall, we provided a comprehensive view of the dynamics of host immunity after SARS-CoV-2 infection that enabled us to understand COVID-19 heterogeneity from systemic perspective.

16.
PLoS Negl Trop Dis ; 15(8): e0009695, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34403421

RESUMO

BACKGROUND: Brucellosis, as a serious zoonotic infectious disease, has been recognized as a re-emerging disease in the developing countries worldwide. In china, the incidence of brucellosis is increasing each year, seriously threatening the health of humans as well as animal populations. Despite a quite number of diagnostic methods currently being used for brucellosis, innovative technologies are still needed for its rapid and accurate diagnosis, especially in area where traditional diagnostic is unavailable. METHODOLOGY/PRINCIPAL FINDINGS: In this study, a total of 22 B cell linear epitopes were predicted from five Brucella outer membrane proteins (OMPs) using an immunoinformatic approach. These epitopes were then chemically synthesized, and with the method of indirect ELISA (iELISA), each of them displayed a certain degree of capability in identifying human brucellosis positive sera. Subsequently, a fusion protein consisting of the 22 predicted epitopes was prokaryotically expressed and used as diagnostic antigen in a newly established brucellosis testing method, nano-ZnO modified paper-based ELISA (nano-p-ELISA). According to the verifying test using a collection of sera collected from brucellosis and non-brucellosis patients, the sensitivity and specificity of multiepitope based nano-p-ELISA were 92.38% and 98.35% respectively. The positive predictive value was 98.26% and the negative predictive value was 91.67%. The multiepitope based fusion protein also displayed significantly higher specificity than Brucella lipopolysaccharide (LPS) antigen. CONCLUSIONS: B cell epitopes are important candidates for serologically testing brucellosis. Multiepitope fusion protein based nano-p-ELISA displayed significantly sensitivity and specificity compared to Brucella LPS antigen. The strategy applied in this study will be helpful to develop rapid and accurate diagnostic method for brucellosis in human as well as animal populations.


Assuntos
Proteínas da Membrana Bacteriana Externa/análise , Brucella/isolamento & purificação , Brucelose/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Epitopos/análise , Antígenos de Bactérias/análise , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Brucella/genética , Brucella/imunologia , Brucelose/microbiologia , China , Ensaio de Imunoadsorção Enzimática/instrumentação , Epitopos/genética , Epitopos/imunologia , Humanos , Sensibilidade e Especificidade
17.
Sci Rep ; 11(1): 15329, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34321522

RESUMO

Mycoplasma capricolum subsp.subsp. capripneumonia (Mccp) and Mycoplasma mycoides subsp.sbusp. capri (Mmc) cause caprine pleuropneumonia (CCPP) and mycoplasmal pneumonia in goats and sheep (MPGS), respectively. These diseases cannot be identified on clinical symptoms alone and it is laborious to distinguish them using biochemical methods. It is therefore important to establish a simple, rapid identification method for Mccp and Mmc. Here, we report a high-resolution melting (HRM) curve analysis using specific primers based on the Mmc 95010 strain MLC_0560 and Mccp F38 strain MCCPF38_00984 gene sequences. The method was highly specific with intra- and inter-batch coefficients of variation < 1%. The lower limit of detection for Mccp and Mmc was 55 copies/µL and 58 copies/µL, respectively. HRM and fluorescence qPCR results were compared using 106 nasal swabs and 47 lung tissue samples from goats (HRM-qPCR coincidence rate 94.8%; 145/153). Mycoplasma isolation and identification was performed on 30 lung tissue samples and 16 nasal swabs (HRM-culturing coincidence rate 87.0%; 40/46). HRM analysis was more sensitive than fluorescence qPCR and Mycoplasma isolation, indicating the practicality of HRM for accurate and rapid identification of Mccp and Mmc, and diagnosis and epidemiology of CCPP and MPGS.


Assuntos
DNA Bacteriano/genética , Mycoplasma/genética , Pleuropneumonia Contagiosa/diagnóstico , Pneumonia por Mycoplasma/diagnóstico , Animais , Sequência de Bases , Primers do DNA/síntese química , Primers do DNA/metabolismo , Diagnóstico Diferencial , Cabras/microbiologia , Limite de Detecção , Pulmão/microbiologia , Mycoplasma/classificação , Mycoplasma/isolamento & purificação , Cavidade Nasal/microbiologia , Desnaturação de Ácido Nucleico , Pleuropneumonia Contagiosa/microbiologia , Pneumonia por Mycoplasma/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reprodutibilidade dos Testes , Ovinos/microbiologia
18.
Mater Sci Eng C Mater Biol Appl ; 108: 110455, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924042

RESUMO

An amphiphilic biodegradable branched copolymer, mPEG-b-PLGA-g-OCol, was synthesized by grafting copolymer (methoxy polyethylene glycol)-b-Poly (l,d-lactic-co-glycolic acid) (mPEG-b-PLGA) on oligomeric collagen (OCol), to form a branched structure with mPEG-b-PLGA as side chain and OCol as backbone. mPEG-b-PLGA and mPEG-b-PLGA-g-OCol were both amphipathic and can self-assemble into micelles in aqueous solution. The mPEG-b-PLGA-g-OCol micelles showed pH-sensitive behaviors and the particle size below 100 nm in slightly acidic environment such as tumor tissue milieu interieur to perform passive targeting. Observed by SEM, when the solution pH increased from 5 to 9, the morphology of mPEG-b-PLGA-g-OCol micelles changed from small spheres to larger ones to rings. For biodegradable mPEG-b-PLGA-g-OCol, the micelles will gradually degrade in body. Further, doxorubicin (DOX) was effectively loaded in the micelles with drug loading and encapsulation efficiency of 3.48% and 25.8%, respectively. To evaluate antineoplastic effect of DOX-laden micelles in vitro, MTT test, flow cytometry and CLSM were performed and found that DOX-laden micelles exhibited higher cellular proliferation inhibition against HeLa cells. These features indicated that the mPEG-b-PLGA-g-OCol micelles were potential drug carrier for cancer therapy.


Assuntos
Plásticos Biodegradáveis , Portadores de Fármacos , Micelas , Plásticos Biodegradáveis/síntese química , Plásticos Biodegradáveis/química , Plásticos Biodegradáveis/farmacocinética , Plásticos Biodegradáveis/farmacologia , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Poliésteres/síntese química , Poliésteres/química , Poliésteres/farmacocinética , Poliésteres/farmacologia , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/farmacologia
19.
Nat Commun ; 11(1): 5767, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33188189

RESUMO

Enhancing the intrinsic activity and space time yield of Cu based heterogeneous methanol synthesis catalysts through CO2 hydrogenation is one of the major topics in CO2 conversion into value-added liquid fuels and chemicals. Here we report inverse ZrO2/Cu catalysts with a tunable Zr/Cu ratio have been prepared via an oxalate co-precipitation method, showing excellent performance for CO2 hydrogenation to methanol. Under optimal condition, the catalyst composed by 10% of ZrO2 supported over 90% of Cu exhibits the highest mass-specific methanol formation rate of 524 gMeOHkgcat-1h-1 at 220 °C, 3.3 times higher than the activity of traditional Cu/ZrO2 catalysts (159 gMeOHkgcat-1h-1). In situ XRD-PDF, XAFS and AP-XPS structural studies reveal that the inverse ZrO2/Cu catalysts are composed of islands of partially reduced 1-2 nm amorphous ZrO2 supported over metallic Cu particles. The ZrO2 islands are highly active for the CO2 activation. Meanwhile, an intermediate of formate adsorbed on the Cu at 1350 cm-1 is discovered by the in situ DRIFTS. This formate intermediate exhibits fast hydrogenation conversion to methoxy. The activation of CO2 and hydrogenation of all the surface oxygenate intermediates are significantly accelerated over the inverse ZrO2/Cu configuration, accounting for the excellent methanol formation activity observed.

20.
Sci Rep ; 9(1): 17609, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31772341

RESUMO

Atmospheric water vapor increases as air temperature rises, which causes further warming. Thus, understanding the underlying causes of atmospheric water vapor change is vital in climate change research. Here, we conducted detection and attribution analyses of atmospheric precipitable water (PW) changes from 1973-2012 over China using an optimal fingerprinting method by comparing the homogenized radiosonde humidity data with CMIP5 model simulations. Results show that the increase in water vapor can be largely attributed to human activities. The effect of anthropogenic forcing (ANT) can be robustly detected and separated from the response to the natural external forcing (NAT) in the two-signal analysis. The moistening attributable to the ANT forcing explains most of the observed PW increase, while the NAT forcing leads to small moistening. GHGs are the primary moistening contributor responsible for the anthropogenic climate change, and the effect of GHGs can be also clearly detected and successfully attributed to the observed PW increases in a three-signal analysis. The scaling factor is used to adjust the CMIP5 model-projected PW changes over China and the observation-constrained future projections suggest that atmospheric water vapor may increase faster (slower) than that revealed by the raw simulations over whole (eastern) China.

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