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1.
Chemistry ; 28(66): e202202105, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-35998025

RESUMEN

Herein, the synthesis of a new type of catalyst, SBA-M (Schiff complex of different metal types grafted on SBA-15) based on a quaternization reaction, is described. Various amounts of ionic liquid were grafted into the pore channels of SBA-15 using the post-grafting method, which allowed the ionic liquid to be grafted into the pore channels restrictively. Notably, over six cycles, SBA-Mn (0.2) has been shown to maintain its catalytic activity and stability. In addition, a reaction mechanism for the cycloaddition of CO2 with epoxides based on density-functional theory is proposed. The cycloaddition reaction of CO2 and epoxides is an efficient way of carbon fixation. It is demonstrated that the metal coordinated with the oxygen atom of the epoxides and that a halogen attacked the carbon of epoxides. Moreover, theoretical calculations and synthesis strategy provide a new approach for CO2 conversion.

2.
Altern Ther Health Med ; 28(1): 86-91, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34453505

RESUMEN

Rickets is one of the most prevalent non-communicable diseases in children in the developing world. It is often found in cultures in which children follow strict vegetarian diets and are not exposed to vitamin D-enhanced foods. While a rare occurrence, X-linked hypophosphatemic rickets may be the most frequent type of the disease seen outside the Third World today. However, there is not much credible information on the extent of the development of rickets. Therefore, pediatric nurses must be able to recognize children at risk and provide best practice care for the prevention and treatment of rickets. When caring for children in hospitals, communities or classrooms, nurses play a vital role in identifying children at risk for hypovitaminosis D and advising families to, if possible, follow safe diets and take supplements in order to avoid health complications associated with low levels of vitamin D. This study examines the prevalence and variables contributing to rickets, including hypovitaminosis vitamin D, the consequent orthopedic problems and the role of nurses in preventing and managing the pathogenesis of rickets and ultimately avoiding extreme deficits that result in bone deformities and the need for corrective surgery.


Asunto(s)
Raquitismo , Deficiencia de Vitamina D , Niño , Suplementos Dietéticos , Humanos , Raquitismo/epidemiología , Raquitismo/terapia , Vitamina D/uso terapéutico , Deficiencia de Vitamina D/epidemiología , Vitaminas
3.
Appl Microbiol Biotechnol ; 105(14-15): 5915-5929, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34292355

RESUMEN

Arginine is an important amino acid involved in processes such as cell signal transduction, protein synthesis, and sexual reproduction. To understand the biological roles of arginine biosynthesis in pathogenic fungi, we used Cpa1, the carbamoyl phosphate synthase arginine-specific small chain subunit in Saccharomyces cerevisiae as a query to identify its ortholog in the Magnaporthe oryzae genome and named it MoCpa1. MoCpa1 is a 471-amino acid protein containing a CPSase_sm_chain domain and a GATase domain. MoCpa1 transcripts were highly expressed at the conidiation, early-infection, and late-infection stages of the fungus. Targeted deletion of the MoCPA1 gene resulted in a ΔMocpa1 mutant exhibiting arginine auxotrophy on minimum culture medium (MM), confirming its role in de novo arginine biosynthesis. The ΔMocpa1 mutant presented significantly decreased sporulation with some of its conidia being defective in morphology. Furthermore, the ΔMocpa1 mutant was nonpathogenic on rice and barley leaves, which was a result of defects in appressorium-mediated penetration and restricted invasive hyphal growth within host cells. Addition of exogenous arginine partially rescued conidiation and pathogenicity defects on the barley and rice leaves, while introduction of the MoCPA1 gene into the ΔMocpa1 mutant fully complemented the lost phenotype. Further confocal microscopy examination revealed that MoCpa1 is localized in the mitochondria. In summary, our results demonstrate that MoCpa1-mediated arginine biosynthesis is crucial for fungal development, conidiation, appressorium formation, and infection-related morphogenesis in M. oryzae, thus serving as an attractive target for mitigating obstinate fungal plant pathogens. KEY POINTS: • MoCpa1 is important for aerial hyphal growth and arginine biosynthesis. • MoCpa1 is pivotal for conidial morphogenesis and appressorium formation. • MoCpa1 is crucial for full virulence in M. oryzae.


Asunto(s)
Magnaporthe , Oryza , Arginina , Ascomicetos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Magnaporthe/genética , Magnaporthe/metabolismo , Oryza/metabolismo , Enfermedades de las Plantas , Esporas Fúngicas/metabolismo
4.
Plant Dis ; 105(11): 3723-3726, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33978433

RESUMEN

Tea gray blight is one of the most serious foliar diseases of tea tree, caused by the plant-pathogenic fungus Pseudopestalotiopsis theae, which can affect production and quality of tea worldwide. We generated a highly contiguous, 50.41-Mbp genome assembly (N50 = 1.30 Mbp) of P. theae strain CYF27 by combining PacBio long-read and Illumina short-read sequencing technologies. We identified a total of 15,626 gene models, of which 1,038 genes encode putative secreted proteins. The high-quality genome assembly and annotation resource reported here will be useful for the study of fungal infection mechanisms and pathogen-host interaction.


Asunto(s)
Ascomicetos , Enfermedades de las Plantas , Ascomicetos/genética , Análisis de Secuencia de ADN ,
5.
J Biol Chem ; 294(47): 17837-17847, 2019 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-31624151

RESUMEN

The Krüppel-like factor 5 (KLF5) transcription factor is highly expressed in basal type breast cancer and promotes breast cancer cell proliferation, survival, migration, and tumorigenesis. KLF5 protein stability is regulated by ubiquitination. In this study, ubiquitin-specific protease 3 (USP3) was identified as a new KLF5 deubiquitinase by genome-wide siRNA library screening. We demonstrated that USP3 interacts with KLF5 and stabilizes KLF5 via deubiquitination. USP3 knockdown inhibits breast cancer cell proliferation in vitro and tumorigenesis in vivo, which can be partially rescued by ectopic expression of KLF5. Furthermore, we observed a positive correlation between USP3 and KLF5 protein expression levels in human breast cancer samples. These findings suggest that USP3 is a new KLF5 deubiquitinase and that USP3 may represent a potential therapeutic target for breast cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Factores de Transcripción de Tipo Kruppel/metabolismo , Proteasas Ubiquitina-Específicas/metabolismo , Ubiquitinación , Animales , Línea Celular Tumoral , Proliferación Celular , Femenino , Células HEK293 , Humanos , Ratones Desnudos , Unión Proteica , Estabilidad Proteica , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología
6.
Mol Cell Biochem ; 449(1-2): 73-79, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29644526

RESUMEN

Dyslipidemia in patients with hypercholesterolemia has been recently linked to increased human cathelicidin LL-37 (LL-37) serum concentration. We tested a hypothesis that upregulated expression of LL-37 gene in peripheral blood leucocytes is involved in dyslipidemia in patients with hypercholesteremia. Patients with hypercholesterolemia were used in the study. Expression of LL-37 and human glyceraldehyde-3-phosphate dehydrogenase in peripheral blood leucocytes were quantified by real-time RT-PCR. Serum LL-37 concentration was estimated by enzyme-linked immunosorbent assay. Serum lipid levels were assessed by absorptiometry in all cases. Patients with hypercholesterolemia as compared to control ones were characterized by (a) an up-regulation of LL-37 gene expression in peripheral blood leucocytes with parallel increase of serum LL-37 concentration and (b) an increase of serum total and low-density lipoprotein cholesterol concentrations. Patients with hypercholesterolemia after a treatment with atorvastatin calcium 20 mg daily as compared to that patients before the treatment: an down-regulation of LL-37 gene expression in peripheral blood leucocytes with parallel decrease of serum LL-37 concentration. We also found significant correlation between serum LL-37 and high-density lipoprotein cholesterol levels (r = 0.7290, P < 0.0001). The results suggest that hypercholesterolemia is associated with an increased LL-37 gene expression in peripheral blood leucocytes. The correlation between serum LL-37 and high-density lipoprotein cholesterol levels suggests that LL-37 may play a key role in regulation of cholesterol levels in hypercholesterolemia.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/biosíntesis , HDL-Colesterol/sangre , Hipercolesterolemia/sangre , Leucocitos/metabolismo , Regulación hacia Arriba , Adulto , Anciano , Femenino , Humanos , Hipercolesterolemia/patología , Leucocitos/patología , Masculino , Persona de Mediana Edad , Catelicidinas
7.
Opt Express ; 24(14): 15222-31, 2016 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-27410800

RESUMEN

The detector in a highly accurate and high-definition scanning 3D imaging lidar system requires high frequency bandwidth and sufficient photosensitive area. To solve the problem of small photosensitive area of an existing indium gallium arsenide detector with a certain frequency bandwidth, this study proposes a method for increasing the receiving field of view (FOV) and enlarging the effective photosensitive aperture of such detector through hexagonal prism beam splitting. The principle and construction of hexagonal prism beam splitting is also discussed in this research. Accordingly, a receiving optical system with two hexagonal prisms is provided and the splitting beam effect of the simulation experiment is analyzed. Using this novel method, the receiving optical system's FOV can be improved effectively up to ±5°, and the effective photosensitive aperture of the detector is increased from 0.5 mm to 1.5 mm.

8.
J Surg Res ; 201(1): 105-17, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26850191

RESUMEN

BACKGROUND: Surgical site infection (SSI) is the third most frequent type of nosocomial infections. Triclosan-coated sutures are often used to reduce the risk of SSI, but studies examining this have given conflicting results. Therefore, this meta-analysis was performed to assess the efficacy of triclosan-coated sutures for reducing risk of SSI in adults. METHODS: PubMed, EMBASE, Google Scholar, and ClinicalTrials.gov were searched to identify randomized clinical trials evaluating triclosan-coated sutures for preventing SSI on patients 18 y or older. RESULTS: Thirteen randomized clinical trials involving 5256 participants were included. Triclosan-coated sutures were associated with lower risk of SSI than uncoated sutures across all surgeries (risk ratio [RR] 0.76, 95% confidence interval [CI] 0.65-0.88, P < 0.001). Similar proportions of patients experienced wound dehiscence with either type of suture (RR 0.97, 95% CI 0.49-1.89, P = 0.92). Subgroup analysis showed lower risk of SSI with triclosan-coated sutures in abdominal surgeries (RR 0.70, 95% CI 0.50-0.99, P = 0.04) and group with prophylactic antibiotic (RR 0.79, 95% CI 0.63-0.99, P = 0.04). However, such risk reduction was not observed in cardiac surgeries, breast surgeries, or group without prophylactic antibiotic. CONCLUSIONS: Triclosan-coated sutures can decrease the incidence of SSI in abdominal surgeries and might not interfere with wound healing process. Nevertheless, further studies are needed to examine whether triclosan-coated sutures are effective at preventing SSI in non-abdominal surgeries and to further study the interaction of antibiotic prophylaxis with triclosan-coated sutures.


Asunto(s)
Antiinfecciosos Locales/administración & dosificación , Dehiscencia de la Herida Operatoria/prevención & control , Infección de la Herida Quirúrgica/prevención & control , Suturas , Triclosán/administración & dosificación , Adulto , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Suturas/economía
9.
Appl Opt ; 55(7): 1559-64, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26974613

RESUMEN

The direction rule of the laser beam traveling through a deflected polarizing beam splitter (PBS) cube is derived. It reveals that, due to the influence of end-face reflection of the PBS at the detector side, the emergent beam coming from the incident beam parallels the direction of the original case without rotation, with only a very small translation interval between them. The formula of the translation interval is also given. Meanwhile, the emergent beam from the return signal at the detector side deflects at an angle twice that of the PBS rotation angle. The correctness has been verified by an experiment. The intensity transmittance of the emergent beam when propagating in the PBS is changes very little if the rotation angle is less than 35 deg. In a 3D imaging lidar system, by rotating the PBS cube by an angle, the direction of the return signal optical axis is separated from that of the origin, which can decrease or eliminate the influence of direct reflection caused by the prism end face on target return signal detection. This has been checked by experiment.

10.
Antonie Van Leeuwenhoek ; 108(6): 1331-1339, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26373415

RESUMEN

Two novel actinomycetes, designated strains NEAU-Jh1-3(T) and NEAU-Jh2-5(T), were isolated from muddy soil collected from a riverbank in Jiaohe, Jilin Province, north China. A polyphasic study was carried out to establish the taxonomic positions of these strains. The 16S rRNA gene sequence analysis showed that the two novel isolates exhibited 99.9 % 16S rRNA gene sequence similarity with each other and that they are closely related to Actinomadura viridis IFO 15238(T) (99.6, 99.6 %) and Actinomadura vinacea IFO 14688(T) (99.3, 99.3 %). Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the two cultures clustered together and formed a cluster with A. viridis IFO 15238(T), A. vinacea IFO 14688(T) and Actinomadura rugatobispora IFO 14382(T). However, the DNA-DNA hybridization value between strains NEAU-Jh1-3(T) and NEAU-Jh2-5(T) was 63.6 %, and the values between the two strains and their close phylogenetic relatives were also below 70 %. With reference to phenotypic characteristics, phylogenetic data and DNA-DNA hybridization results, the two strains can be distinguished from each other and their close phylogenetic relatives. Thus, strains NEAU-Jh1-3(T) and NEAU-Jh2-5(T) represent two novel species of the genus Actinomadura, for which the names Actinomadura jiaoheensis sp. nov. and Actinomadura sporangiiformans sp. nov. are proposed. The type strains are NEAU-Jh1-3(T) (=CGMCC 4.7197(T) = JCM 30341(T)) and NEAU-Jh2-5(T) (=CGMCC 4.7211(T) = JCM 30342(T)), respectively.


Asunto(s)
Actinobacteria/clasificación , Actinobacteria/aislamiento & purificación , Microbiología del Suelo , Actinobacteria/genética , Actinobacteria/fisiología , Técnicas de Tipificación Bacteriana , China , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Microscopía Electrónica de Rastreo , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
11.
Appl Opt ; 54(33): 9799-802, 2015 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-26836540

RESUMEN

Al2O3 nanoparticles modified with different chemical reagents, prepared by using three chemical dispersants [high definition (HD), sodium dodecyl benzene sulfonate, and cetyl trimethyl ammonium chloride], were doped into photopolymer films in a polyvinyl alcohol/acrylamide (PVA/AA) system, respectively. A 647 nm Ar-Kr laser was used to expose and study the holographic properties of the samples. The research shows that doping Al2O3 nanoparticles into PVA/AA photopolymer film leads to different levels of improvement of the holographic characteristics. The diffraction efficiency of the sample can be raised to 93.8%, the maximum refractive index modulation increased to 2.28×10(-3), the shrinkage can be depressed to 0.8%, and the Bragg mismatch is 0.04°, while the concentration of 10 nm Al2O3 nanoparticles modified by HD dispersant is 1.02×10(-3) mol·L(-1).

12.
Cancer Imaging ; 24(1): 62, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750551

RESUMEN

OBJECTIVES: To develop and validate radiomics model based on computed tomography (CT) for preoperative prediction of CN0 status in patients with papillary thyroid carcinoma (PTC). METHODS: A total of 548 pathologically confirmed LNs (243 non-metastatic and 305 metastatic) two distinct hospitals were retrospectively assessed. A total of 396 radiomics features were extracted from arterial-phase CT images, where the strongest features containing the most predictive potential were further selected using the least absolute shrinkage and selection operator (LASSO) regression method. Delong test was used to compare the AUC values of training set, test sets and cN0 group. RESULTS: The Rad-score showed good discriminating performance with Area Under the ROC Curve (AUC) of 0.917(95% CI, 0.884 to 0.950), 0.892 (95% CI, 0.833 to 0.950) and 0.921 (95% CI, 868 to 0.973) in the training, internal validation cohort and external validation cohort, respectively. The test group of CN0 with a AUC of 0.892 (95% CI, 0.805 to 0.979). The accuracy was 85.4% (sensitivity = 81.3%; specificity = 88.9%) in the training cohort, 82.9% (sensitivity = 79.0%; specificity = 88.7%) in the internal validation cohort, 85.4% (sensitivity = 89.7%; specificity = 83.8%) in the external validation cohort, 86.7% (sensitivity = 83.8%; specificity = 91.3%) in the CN0 test group.The calibration curve demonstrated a significant Rad-score (P-value in H-L test > 0.05). The decision curve analysis indicated that the rad-score was clinically useful. CONCLUSIONS: Radiomics has shown great diagnostic potential to preoperatively predict the status of cN0 in PTC.


Asunto(s)
Cáncer Papilar Tiroideo , Neoplasias de la Tiroides , Tomografía Computarizada por Rayos X , Humanos , Femenino , Masculino , Cáncer Papilar Tiroideo/diagnóstico por imagen , Cáncer Papilar Tiroideo/patología , Tomografía Computarizada por Rayos X/métodos , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/patología , Adulto , Anciano , Curva ROC , Adulto Joven , Radiómica
13.
Front Cell Infect Microbiol ; 14: 1395267, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38817449

RESUMEN

Background: Traditional Chinese medicine (TCM) comprising herbal formulas has been used for millennia to treat various diseases, such as insomnia, based on distinct syndrome types. Although TCM has been proposed to be effective in insomnia through gut microbiota modulation in animal models, human studies remain limited. Therefore, this study employs machine learning and integrative network techniques to elucidate the role of the gut microbiome in the efficacies of two TCM formulas - center-supplementing and qi-boosting decoction (CSQBD) and spleen-tonifying and yin heat-clearing decoction (STYHCD) - in treating insomnia patients diagnosed with spleen qi deficiency and spleen qi deficiency with stomach heat. Methods: Sixty-three insomnia patients with these two specific TCM syndromes were enrolled and treated with CSQBD or STYHCD for 4 weeks. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) and Insomnia Severity Index (ISI) every 2 weeks. In addition, variations in gut microbiota were evaluated through 16S rRNA gene sequencing. Stress and inflammatory markers were measured pre- and post-treatment. Results: At baseline, patients exhibiting only spleen qi deficiency showed slightly lesser severe insomnia, lower IFN-α levels, and higher cortisol levels than those with spleen qi deficiency with stomach heat. Both TCM syndromes displayed distinct gut microbiome profiles despite baseline adjustment of PSQI, ISI, and IFN-α scores. The nested stratified 10-fold cross-validated random forest classifier showed that patients with spleen qi deficiency had a higher abundance of Bifidobacterium longum than those with spleen qi deficiency with stomach heat, negatively associated with plasma IFN-α concentration. Both CSQBD and STYHCD treatments significantly improved sleep quality within 2 weeks, which lasted throughout the study. Moreover, the gut microbiome and inflammatory markers were significantly altered post-treatment. The longitudinal integrative network analysis revealed interconnections between sleep quality, gut microbes, such as Phascolarctobacterium and Ruminococcaceae, and inflammatory markers. Conclusion: This study reveals distinct microbiome profiles associated with different TCM syndrome types and underscores the link between the gut microbiome and efficacies of Chinese herbal formulas in improving insomnia. These findings deepen our understanding of the gut-brain axis in relation to insomnia and pave the way for precision treatment approaches leveraging TCM herbal remedies.


Asunto(s)
Medicamentos Herbarios Chinos , Microbioma Gastrointestinal , Medicina Tradicional China , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Microbioma Gastrointestinal/efectos de los fármacos , Trastornos del Inicio y del Mantenimiento del Sueño/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Masculino , Femenino , Persona de Mediana Edad , Adulto , ARN Ribosómico 16S/genética , Bazo/microbiología , Síndrome , Qi
14.
Front Cardiovasc Med ; 10: 1091778, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37008325

RESUMEN

Background and objective: Syncope is a common emergency with diverse etiologies in children. Among these, cardiac syncope (CS) is associated with high mortality and is usually difficult to diagnose. However, there is still no validated clinical prediction model to distinguish CS from other forms of pediatric syncope. The Evaluation of Guidelines in Syncope Study (EGSYS) score was designed to identify CS in adults and has been validated in several studies. In this study, we aimed to assess the ability of the EGSYS score in predicting CS in children. Methods: In this retrospective study, we calculated and analyzed the EGSYS scores of 332 children hospitalized for syncope between January 2009 and December 2021. Among them, 281 were diagnosed with neurally mediated syncope (NMS) through the head-up tilt test, and 51 were diagnosed with CS using electrocardiography (ECG), echocardiography (ECHO), coronary computed tomography angiography (CTA), myocardial enzymes and genetic screening. The receiver operating characteristic (ROC) curve and Hosmer-Lemeshow test were used to evaluate the predictive value of the EGSYS score system. Results: The median scores of 51 children with CS and 281 children with NMS were 4 [interquartile range (IQR): 3-5] and -1 (IQR: -2-1), respectively. The area under the ROC curve (AUC) was 0.922 [95% confidence interval (CI): 0.892-0.952; P < 0.001], indicating that the EGSYS score system has good discrimination. The best cutoff point was ≥3, with a sensitivity and specificity of 84.3% and 87.9%, respectively. The Hosmer-Lemeshow test demonstrated satisfactory calibration (χ²=1.468, P > 0.05) of the score, indicating a good fit of the model. Conclusion: The EGSYS score appeared to be sensitive for differentiating CS from NMS in children. It might be used as an additional diagnostic tool to aid pediatricians in accurately identifying children with CS in the clinical practice.

15.
Polymers (Basel) ; 15(15)2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37571097

RESUMEN

Blend proton exchange membranes (BPEMs) were prepared by blending sulfonated poly(aryl ether nitrile) (SPAEN) with phosphorylated poly(vinylbenzyl chloride) (PPVBC) and named as SPM-x%, where x refers to the proportion of PPVBC to the weight of SPAEN. The chemical complexation interaction between the phosphoric acid and sulfonic acid groups in the PPVBC-SPAEN system resulted in BPEMs with reduced water uptake and enhanced mechanical properties compared to SPAEN proton exchange membranes. Furthermore, the flame retardancy of the PPVBC improved the thermal stability of the BPEMs. Despite a decrease in ion exchange capacity, the proton conductivity of the BPEMs in the through-plane direction was significantly enhanced due to the introduction of phosphoric acid groups, especially in low relative humidity (RH) environments. The measured proton conductivity of SPM-8% was 147, 98, and 28 mS cm-1 under 95%, 70%, and 50% RH, respectively, which is higher than that of the unmodified SPAEN membrane and other SPM-x% membranes. Additionally, the morphology and anisotropy of the membrane proton conductivities were analyzed and discussed. Overall, the results indicated that PPVBC doping can effectively enhance the mechanical and electrochemical properties of SPAEN membranes.

16.
RSC Adv ; 13(16): 11062-11068, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37063245

RESUMEN

The modification of the physicochemical properties of sulfonated poly(arylene ether nitrile) (SPAEN) proton exchange membranes was demonstrated by poly(ethylene-co-vinyl alcohol) (EVOH) doping (named SPAEN-x%). By controlling the temperature during membrane preparation, the side reactions of the sulfonic acid groups to form sulfonic acid esters were effectively prevented, greatly reducing the proton conductivity of the membranes. Due to the flexible chain of EVOH, SPAEN-8% showed a relatively high elongation of 30.2%, which enhanced the aromatic polymers' flexibility. The SPAEN-2% membrane exhibited proton conductivity of 166, 55, and 9.6 mS cm-1 at 95%, 70%, and 50% relative humidity, respectively, higher than those of the other SPAEN-x% membranes and even comparable to that of Nafion 212. The water uptake, morphological study, and through-plane proton conductivity of the membranes were studied and discussed. The results suggest that EVOH doping can be used as an effective strategy to improve SPAEN-based proton exchange membranes' performance.

17.
Mol Plant Pathol ; 22(9): 1159-1164, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34117700

RESUMEN

Polar growth during appressorium formation is vital for the penetration peg formation in the rice blast fungus, Magnaporthe oryzae. Previous research has shown that the Sln1-septin-exocyst complex, localized at the base of the appressorium in contact with the leaf surface, forms a ring structure that influences growth polarity and affects penetration peg formation, and is necessary for pathogenicity. Our previous research showed CK2 proteins assemble another ring structure positioned perpendicular to the Sln1-septin-exocyst complex. Our research showed that the CK2 ring needs to become correctly assembled for penetration peg function and subsequent plant infection. In the present study, we found that the ring structures of CK2 are absent in the appressorium of ΔMoSep3 septin deletion mutants lacking the septin ring of the Sln1-septin-exocyst complex. Sln1 affects the septin proteins that recruit the exocyst complex that localizes as another ring at the appressorium's bottom. Destruction of the exocyst complex by mutation also causes incorrect localization of the CK2 ring structure. In conclusion, CK2 probably takes part in reestablishing the appressorium' spolarity growth necessary for penetration peg formation. We can also conclude that the correct localization and assembly of one or more CK2 ring structures in the appressorium depend on the initial assembly of the Sln1-septin-exocyst complex two rings at the base of the appressorium.


Asunto(s)
Magnaporthe , Oryza , Ascomicetos , Proteínas Fúngicas/genética , Enfermedades de las Plantas
18.
Pest Manag Sci ; 77(10): 4669-4679, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34116584

RESUMEN

BACKGROUND: Sanguinarine (SAN) is a benzophenanthridine alkaloid that broadly targets a range of pathways in mammalian and fungal cells. In this study we set out to explore the molecular mechanism of sanguinarine inhibition of the fungal development and pathogenicity of Magnaporthe oryzae with the hope that sanguinarine will bolster the development of antiblast agents. RESULTS: We found that the fungus exhibited a significant reduction in vegetative growth and hyphal melanization while the spores produced long germ tubes on the artificial hydrophobic surface characteristic of a defect in thigmotropic sensing when exposed to 4, 8 and 0.5 µm sanguinarine, respectively. Consistent with these findings, we observed that the genes involved in melanin biosynthesis and the fungal hydrophobin MoMPG1 were remarkably suppressed in mycelia treated with 8 µm sanguinarine. Additionally, sanguinarine inhibited appressorium formation at a dose of 1.0 µm and this defect was restored by supplementing 5 mM of exogenous cAMP. By qRT-PCR assay we found cAMP pathway signalling genes such as MoCAP1 and MoCpkA were significantly repressed whereas MoCDTF1 and MoSOM1 were upregulated in sanguinarine-treated strains. Furthermore, we showed that sanguinarine does not selectively inhibit vegetative growth and appressorium formation of Guy11 but also other strains of M. oryzae. Finally, treatment of sanguinarine impaired the appressorium-mediated penetration and pathogenicity of M. oryzae in a dose-dependent manner. CONCLUSION: Based on our results we concluded that sanguinarine is an attractive antimicrobial candidate for fungicide development in the control of rice blast disease. © 2021 Society of Chemical Industry.


Asunto(s)
Magnaporthe , Oryza , Ascomicetos , Benzofenantridinas/farmacología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Isoquinolinas , Oryza/metabolismo , Enfermedades de las Plantas , Virulencia
19.
Biotechnol Adv ; 37(5): 599-615, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30849433

RESUMEN

Alternative chemicals to diverse fossil-fuel-based products is urgently needed to mitigate the adverse impacts of fossil fuel depletion on human development. To this end, researchers have focused on the production of biochemical from readily available and affordable waste biomass. This is consistent with current guidelines for sustainable development and provides great advantages related to economy and environment. The search for suitable biochemical products is in progress worldwide. Therefore, this review recommends a biochemical (i.e., medium chain carboxylic acids (MCCAs)) utilizing an emerging biotechnological production platform called the chain elongation (CE) process. This work covers comprehensive introduction of the CE mechanism, functional microbes, available feedstock types and corresponding utilization strategies, major methods to enhance the performance of MCCAs production, and the challenges that need to be addressed for practical application. This work is expected to provide a thorough understanding of the CE technology, to guide and inspire researchers to solve existing problems in depth, and motivate large-scale MCCAs production.


Asunto(s)
Biotecnología/métodos , Ácidos Carboxílicos/metabolismo , Biocombustibles , Biomasa , Reactores Biológicos , Biotecnología/instrumentación , Ácidos Carboxílicos/química , Clostridium kluyveri/metabolismo , Eubacterium/metabolismo , Fermentación , Microbiología Industrial/métodos , Megasphaera elsdenii/metabolismo , Residuos
20.
J Vis Exp ; (138)2018 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-30124649

RESUMEN

This study aimed to make an explanation for the phenomenon in nature that water strider usually jumps or glides on the water surface easily but quickly, with its peak locomotion speed reaching 150 cm/s. First of all, we observed the microstructure and hierarchy of water strider legs using the scanning electron microscope. On the basis of the observed morphology of the legs, a theoretical model of the detachment from water surface was established, which explained water striders' capability to slide on water surface effortlessly in terms of energy reduction. Secondly, a dynamic force measurement system was devised using the PVDF film sensor with excellent sensitivity, which could detect the whole interaction process. Subsequently, a single leg in contact with water was pulled upward at different speeds, and the adhesion force was measured at the same time. The results of the departing experiment suggested a deep understanding of the fast jumping of water striders.


Asunto(s)
Polivinilos/química , Agua/química
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