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1.
Plant Cell ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833610

RESUMO

Reactive oxygen species (ROS) production is a key event in modulating plant responses to hypoxia and post-hypoxia reoxygenation. However, the molecular mechanism by which hypoxia-associated ROS homeostasis is controlled remains largely unknown. Here, we showed that the calcium-dependent protein kinase CPK16 regulates plant hypoxia tolerance by phosphorylating the plasma membrane-anchored NADPH oxidase RESPIRATORY BURST OXIDASE HOMOLOG D (RBOHD) to regulate ROS production in Arabidopsis (Arabidopsis thaliana). In response to hypoxia or reoxygenation, CPK16 was activated through phosphorylation of its Ser274 residue. The cpk16 knockout mutant displayed enhanced hypoxia tolerance, whereas CPK16-overexpressing (CPK16-OE) lines showed increased sensitivity to hypoxic stress. In agreement with these observations, hypoxia and reoxygenation both induced ROS accumulation in the rosettes of CPK16-OEs more strongly than in rosettes of the cpk16-1 mutant or the wild type. Moreover, CPK16 interacted with and phosphorylated the N terminus of RBOHD at four serine residues (Ser133, Ser148, Ser163, and Ser347) that were necessary for hypoxia- and reoxygenation-induced ROS accumulation. Furthermore, the hypoxia-tolerant phenotype of cpk16-1 was fully abolished in the cpk16 rbohd double mutant. Thus, we have uncovered a regulatory mechanism by which the CPK16-RBOHD module shapes ROS production during hypoxia and reoxygenation in Arabidopsis.

2.
Nature ; 579(7797): 118-122, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32103178

RESUMO

It has long been assumed that lifespan and healthspan correlate strongly, yet the two can be clearly dissociated1-6. Although there has been a global increase in human life expectancy, increasing longevity is rarely accompanied by an extended healthspan4,7. Thus, understanding the origin of healthy behaviours in old people remains an important and challenging task. Here we report a conserved epigenetic mechanism underlying healthy ageing. Through genome-wide RNA-interference-based screening of genes that regulate behavioural deterioration in ageing Caenorhabditis elegans, we identify 59 genes as potential modulators of the rate of age-related behavioural deterioration. Among these modulators, we found that a neuronal epigenetic reader, BAZ-2, and a neuronal histone 3 lysine 9 methyltransferase, SET-6, accelerate behavioural deterioration in C. elegans by reducing mitochondrial function, repressing the expression of nuclear-encoded mitochondrial proteins. This mechanism is conserved in cultured mouse neurons and human cells. Examination of human databases8,9 shows that expression of the human orthologues of these C. elegans regulators, BAZ2B and EHMT1, in the frontal cortex increases with age and correlates positively with the progression of Alzheimer's disease. Furthermore, ablation of Baz2b, the mouse orthologue of BAZ-2, attenuates age-dependent body-weight gain and prevents cognitive decline in ageing mice. Thus our genome-wide RNA-interference screen in C. elegans has unravelled conserved epigenetic negative regulators of ageing, suggesting possible ways to achieve healthy ageing.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Epigênese Genética , Envelhecimento Saudável/genética , Histona-Lisina N-Metiltransferase/metabolismo , Fatores Genéricos de Transcrição/metabolismo , Envelhecimento/genética , Animais , Proteínas de Caenorhabditis elegans/genética , Cognição , Disfunção Cognitiva , Histona-Lisina N-Metiltransferase/deficiência , Histona-Lisina N-Metiltransferase/genética , Histonas/química , Histonas/metabolismo , Humanos , Longevidade/genética , Lisina/metabolismo , Masculino , Memória , Metilação , Camundongos , Mitocôndrias/metabolismo , Neurônios/metabolismo , Proteínas/genética , Interferência de RNA , Aprendizagem Espacial , Fatores Genéricos de Transcrição/deficiência , Fatores Genéricos de Transcrição/genética
3.
Genomics ; 116(5): 110893, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38944355

RESUMO

Understanding phytohormonal signaling is crucial for elucidating plant defense mechanisms against environmental stressors. However, knowledge regarding phytohormone-mediated tolerance pathways under salt stress in Elymus sibiricus, an important species for forage and ecological restoration, remains limited. In this study, transcriptomic and metabolomic approaches uncover the dynamics of phytohormonal signaling in Elymus sibiricus under salt stress. Notably, four hours after exposure to salt, significant activity was observed in the ABA, JA, IAA, and CTK pathways, with ABA, JA, JA-L-Ile, and IAA identified as key mediators in the response of Elymus sibiricus' to salinity. Moreover, SAPK3, Os04g0167900-like, CAT1, MKK2, and MPK12 were identified as potential central regulators within these pathways. The complex interactions between phytohormones and DEGs are crucial for facilitating the adaptation of Elymus sibiricus to saline environments. These findings enhance our understanding of the salt tolerance mechanisms in Elymus sibiricus and provide a foundation for breeding salt-resistant varieties.

4.
Appl Microbiol Biotechnol ; 107(2-3): 677-689, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36572830

RESUMO

Pectate lyases (Pels) have a vital function in degradation of the primary plant cell wall and the middle lamella and have been widely used in the industry. In this study, two pectate lyase genes, IDSPel16 and IDSPel17, were cloned from a sheep rumen microbiome. The recombinant enzymes were expressed in Escherichia coli and functionally characterized. Both IDSPel16 and IDSPel17 proteins had an optimal temperature of 60 ℃, and an optimal pH of 10.0. IDSPel16 was relatively stable below 60 °C, maintaining 77.51% residual activity after preincubation at 60 °C for 1 h, whereas IDSPel17 denatured rapidly at 60 °C. IDSPel16 was relatively stable between pH 6.0 and 12.0, after pretreatment for 1 h, retaining over 60% residual activity. IDSPel16 had high activity towards polygalacturonic acid, with a Vmax of 942.90 ± 68.11, whereas IDSPel17 had a Vmax of only 28.19 ± 2.23 µmol/min/mg. Reaction product analyses revealed that IDSPel17 liberated unsaturated digalacturonate (uG2) and unsaturated trigalacturonate (uG3) from the substrate, indicating a typical endo-acting pectate lyase (EC 4.2.2.2). In contrast, IDSPel16 initially generated unsaturated oligogalacturonic acids, then converted these intermediates into uG2 and unsaturated galacturonic acid (uG1) as end products, a unique depolymerization profile among Pels. To the best of our knowledge, the IDSPel16 discovered with both endo-Pel (EC 4.2.2.2) and exo-Pel (EC 4.2.2.9) activities. These two pectate lyases, particularly the relatively thermo- and pH-stable IDSPel16, will be of interest for potential application in the textile, food, and feed industries. KEY POINTS: • Two novel pectate lyase genes, IDSPel16 and IDSPel17, were isolated and characterized from the sheep rumen microbiome. • Both IDSPel16 and IDSPel17 are alkaline pectate lyases, releasing unsaturated digalacturonate and unsaturated trigalacturonate from polygalacturonic acid. • IDSPel16, a bifunctional pectate lyase with endo-Pel (EC 4.2.2.2) and exo-Pel (EC 4.2.2.9) activities, could be a potential candidate for industrial application.


Assuntos
Polissacarídeo-Liases , Rúmen , Animais , Ovinos , Rúmen/metabolismo , Polissacarídeo-Liases/metabolismo , Clonagem Molecular
5.
BMC Genomics ; 23(1): 15, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34983398

RESUMO

BACKGROUND: Neonicotinoids are widely applied in the control of the destructive agricultural pest Bemisia tabaci, and resistance against these chemicals has become a common, severe problem in the control of whiteflies. To investigate the molecular mechanism underlying resistance against nenonicotinoids in whiteflies, RNA-seq technology was applied, and the variation in the transcriptomic profiles of susceptible whiteflies and whiteflies selected by imidacloprid, acetamiprid and thiamethoxam treatment was characterized. RESULTS: A total of 90.86 GB of clean sequence data were obtained from the 4 transcriptomes. Among the 16,069 assembled genes, 584, 110 and 147 genes were upregulated in the imidacloprid-selected strain (IMI), acetamiprid-selected strain (ACE), and thiamethoxam (THI)-selected strain, respectively, relative to the susceptible strain. Detoxification-related genes including P450s, cuticle protein genes, GSTs, UGTs and molecular chaperone HSP70s were overexpressed in the selected resistant strains, especially in the IMI strain. Five genes were downregulated in all three selected resistant strains, including 2 UDP-glucuronosyltransferase 2B18-like genes (LOC 109030370 and LOC 109032577). CONCLUSIONS: Ten generations of selection with the three neonicotinoids induced different resistance levels and gene expression profiles, mainly involving cuticle protein and P450 genes, in the three selected resistant whitefly strains. The results provide a reference for research on resistance and cross-resistance against neonicotinoids in B. tabaci.


Assuntos
Hemípteros , Inseticidas , Animais , Hemípteros/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Neonicotinoides , Nitrocompostos , Tiametoxam
6.
Clin Proteomics ; 19(1): 33, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36002804

RESUMO

Crotonaldehyde (CRA)-one of the major environmental pollutants from tobacco smoke and industrial pollution-is associated with vascular injury (VI). We used proteomics to systematically characterize the presently unclear molecular mechanism of VI and to identify new related targets or signaling pathways after exposure to CRA. Cell survival assays were used to assess DNA damage, whereas oxidative stress was determined using colorimetric assays and by quantitative fluorescence study; additionally, cyclooxygenase-2, mitogen-activated protein kinase pathways, Wnt3a, ß-catenin, phospho-ErbB2, and phospho-ErbB4 were assessed using ELISA. Proteins were quantitated via tandem mass tag-based liquid chromatography-mass spectrometry and bioinformatics analyses, and 34 differentially expressed proteins were confirmed using parallel reaction monitoring, which were defined as new indicators related to the mechanism underlying DNA damage; glutathione perturbation; mitogen-activated protein kinase; and the Wnt and ErbB signaling pathways in VI based on Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and protein-protein interaction network analyses. Parallel reaction monitoring confirmed significant (p < 0.05) upregulation (> 1.5-fold change) of 23 proteins and downregulation (< 0.667-fold change) of 11. The mechanisms of DNA interstrand crosslinks; glutathione perturbation; mitogen-activated protein kinase; cyclooxygenase-2; and the Wnt and ErbB signaling pathways may contribute to VI through their roles in DNA damage, oxidative stress, inflammation, vascular dysfunction, endothelial dysfunction, vascular remodeling, coagulation cascade, and the newly determined signaling pathways. Moreover, the Wnt and ErbB signaling pathways were identified as new disease pathways involved in VI. Taken together, the elucidated underlying mechanisms may help broaden existing understanding of the molecular mechanisms of VI induced by CRA.

7.
BMC Urol ; 22(1): 47, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35346153

RESUMO

BACKGROUND: Despite the continuous development and evolution of surgical methods and techniques, proximal hypospadias remains one of the most challenging issues for pediatric urologists. This study aims to evaluate the indications and postoperative complications of our new modified Duckett urethroplasty. METHODS: A total of 133 patients with proximal hypospadias who underwent repair of the modified Duckett urethroplasty from February 2016 to February 2021 were reviewed. The median age of patients was 3 years (range 1-16). All patients had severe chordee. One senior experienced pediatric urologist performed all the surgeries. Catheter was removed 14 days after the surgery. RESULTS: The location of the urethral meatus was proximal penile in 26 patients (19.5%), penoscrotal in 60 (45.1%), scrotal in 31 (23.3%), and perineal in 16 (12.0%). The mean length of the urethral defect was 4.5 cm (range 2.5-10). The median duration of follow-up was 46 months (range 8-67). Complications occurred in 31 patients (23.3%), including urethra-cutaneous fistula in 22 (16.5%), urethral stenosis in 7 (5.3%), and urethral diverticulum in 2 (1.5%). No recurrent chordee were found in all cases. All patients who developed complications were treated successfully at our hospital. CONCLUSIONS: Our modified Duckett urethroplasty showed functionally and cosmetically favorable outcomes, with a lower incidence of postoperative complications. To the best of our knowledge, the novel Duckett technique is a feasible and suitable option for patients who suffer from proximal hypospadias with severe chordee and dysplasia of the urethral plate.


Assuntos
Hipospadia , Estreitamento Uretral , Adolescente , Criança , Pré-Escolar , Humanos , Hipospadia/etiologia , Hipospadia/cirurgia , Lactente , Masculino , Pênis/cirurgia , Uretra/cirurgia , Estreitamento Uretral/cirurgia , Procedimentos Cirúrgicos Urológicos Masculinos/métodos
8.
World J Microbiol Biotechnol ; 38(5): 87, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35397717

RESUMO

ß-Glucanases are a suite of glycoside hydrolases that depolymerize ß-glucan into cellooligosaccharides and/or monosaccharides and have been widely used as feed additives in livestock. In this study, two novel glucanase genes, IDSGluc5-26 and IDSGluc5-37, derived from sheep rumen microbiota, were expressed and functionally characterized. The optimal temperatures/pH of recombinant IDSGLUC5-26 and IDSGLUC5-37 were 50 °C/5.0 and 40 °C/6.0, respectively. Notably, IDSGLUC5-26 showed considerable stability under acidic conditions. Both IDSGLUC5-26 and IDSGLUC5-37 showed the highest activities toward barley ß-glucan, with Vmax values of 89.96 ± 9.19 µmol/min/mg and 459.50 ± 25.02 µmol/min/mg, respectively. Additionally, these two glucanases demonstrated hydrolysis of Icelandic moss lichenan and konjac gum, IDSGLUC5-26 releasing cellobiose (G2; occupying 17.37% of total reducing sugars), cellotriose (G3; 23.97%), and cellotetraose (G4; 30.93%) from barley ß-glucan and Icelandic moss lichenan after 10 min and suggestive of a typical endo-ß-1,4-glucanase (EC.3.2.1.4). In contrast, IDSGLUC5-37 was capable of liberating dominant G3 (64.11% or 67.55%) from barley ß-glucan or Icelandic moss lichenan, suggesting that the enzyme was likely an endo-ß-1,3 - 1,4-glucanases/lichenase (EC3.2.1.73). These findings describe the expression and characterization of two novel glucanase genes from sheep rumen microbiota. The two recombinant enzymes, particularly the acid-stable IDSGLUC5-26, will be of interest for potential application in food-/feed-additive development.


Assuntos
Microbiota , beta-Glucanas , Sequência de Aminoácidos , Animais , Glicosídeo Hidrolases/metabolismo , Proteínas Recombinantes/metabolismo , Rúmen , Ovinos , Especificidade por Substrato , beta-Glucanas/metabolismo
9.
BMC Cardiovasc Disord ; 21(1): 603, 2021 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-34922451

RESUMO

BACKGROUND: Exposure to glyoxal, the smallest dialdehyde, is associated with several diseases; humans are routinely exposed to glyoxal because of its ubiquitous presence in foods and the environment. The aim of this study was to examine the damage caused by glyoxal in human aortic endothelial cells. METHODS: Cell survival assays and quantitative fluorescence assays were performed to measure DNA damage; oxidative stress was detected by colorimetric assays and quantitative fluorescence, and the mitogen-activated protein kinase pathways were assessed using western blotting. RESULTS: Exposure to glyoxal was found to be linked to abnormal glutathione activity, the collapse of mitochondrial membrane potential, and the activation of mitogen-activated protein kinase pathways. However, DNA damage and thioredoxin oxidation were not induced by dialdehydes. CONCLUSIONS: Intracellular glutathione, members of the mitogen-activated protein kinase pathways, and the mitochondrial membrane potential are all critical targets of glyoxal. These findings provide novel insights into the molecular mechanisms perturbed by glyoxal, and may facilitate the development of new therapeutics and diagnostic markers for cardiovascular diseases.


Assuntos
Aorta/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Glutationa/metabolismo , Glioxal/toxicidade , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Aorta/enzimologia , Aorta/patologia , Células Cultivadas , Dano ao DNA , Células Endoteliais/enzimologia , Células Endoteliais/patologia , Humanos , Mitocôndrias/enzimologia , Mitocôndrias/patologia , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Transdução de Sinais , Tiorredoxinas/metabolismo
10.
Allergy Asthma Proc ; 42(5): 409-416, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34261576

RESUMO

Background: Symptomatic asthma and rhinitis negatively impact patients' work productivity and activity. However, little is known about the potential interaction effect of both asthma and rhinitis control on work productivity and activity impairment. Objective: This study aimed to explore whether there are interaction effects of asthma and rhinitis control on work productivity and activity impairment in patients with asthma and with rhinitis. Methods: A total of 206 adult patients were prospectively recruited and were divided into four groups: both poorly controlled (BPC) n = 53), poorly controlled asthma (PCA) with controlled rhinitis (CR) (n = 38), well controlled asthma with uncontrolled rhinitis (n = 43), and both well controlled (BWC) (n = 72) based on the symptom control status of asthma and rhinitis. Work productivity loss and activity impairment, asthma control, and rhinitis control were assessed by using work productivity and activity impairment questionnaire: general health, the asthma control test, and the rhinitis control assessment test, respectively. General linear regression models were used to study the contribution of asthma control, rhinitis control, and the interaction effect on work productivity and activity impairment. Results: Work productivity loss was most frequently reported in patients in the BPC group. Compared with the patients in the BWC group, the patients in the PCA-CR group had significantly higher activity impairment and worse asthma-related quality of life (both p < 0.001). There were significant interaction effects of asthma and rhinitis control, which accounted for the increase in presenteeism, work productivity loss, and activity impairment (all p < 0.001). Although differences in absenteeism were not significant among the groups, there was a significant interaction effect of control levels accounted for absenteeism (p = 0.035). Conclusion: Distinct interaction effects of asthma and rhinitis control reflected a link between upper and lower airways, which indicated that rhinitis control and the interaction effects of asthma and rhinitis control cannot be neglected during asthma management.


Assuntos
Asma , Eficiência , Rinite , Adulto , Asma/tratamento farmacológico , Asma/epidemiologia , Estudos Transversais , Emprego , Humanos , Qualidade de Vida , Rinite/epidemiologia , Inquéritos e Questionários
11.
Nanotechnology ; 31(37): 375701, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32498050

RESUMO

Facile synthesis of novel rGO-supported AgI decorated TiO2 mesocrystals (AgI-TMCs-rGO) and their photocatalytic activity under visible light irradiation are reported. The catalysts were prepared by combining the hydrothermal reaction process and in situ deposition-precipitation method. The structural features and chemical compositions of the prepared catalysts were investigated by HRTEM (high resolution transmission electron microscopy), XRD (x-ray powder diffraction), Raman spectra, XPS (x-ray photoelectron spectroscopy), UV-vis DRS (UV-vis diffuse reflectance spectra), PLS (photoluminescence spectra), and N2 physisorption measurements. The AgI-TMCs-rGO catalysts featured a large surface area, high adsorption capacity, enhanced photo-induced charge separation and strong absorbance of visible light. The intimate contact of various components and the fast transfer of charge carriers effectively suppresses photolysis of AgI and favors the structural stability of AgI-TMCs-rGO. The photocatalytic activity of the catalysts was evaluated by degrading Rhodamine B (RhB) in an aqueous solution under visible light irradiation. The highest photocatalytic activity was observed in the sample 20%Ag-TMCs-rGO, attributed to the synergistic effects of a lower band gap and a lowerrecombination rate of the charge carriers, along with the larger surface area of the fabricated sample.

12.
Pestic Biochem Physiol ; 163: 209-215, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31973859

RESUMO

Neonicotinoids are commonly used for the control of the whitefly Bemisia tabaci in cotton field. Laboratory test and field experiments have found that whitefly has a high risk of developing resistance and cross-resistance to the pesticide. Over expression of cytochrome P450 is one of the main mechanism that controls pesticide resistance in many insects. In this study we use MEAM1 whitefly, the dominant cryptic species of B. tabaci in Xinjiang cotton field, to investigate the possible resistance and cross-resistance mechanism controlled by cytochrome P450 enzymes. The P450 enzyme activity was higher in both selected strains of imidacloprid and acetamipird than that of susceptible strain. Synergism test showed that piperonyl butoxide (PBO) distinctly increased the control efficiency of imidacloprid and acetamiprid to the two resistance selected strains. Four out of 13 cytochrome genes, CYP4CS3, CYP6CX5, CYP6DW2 and CYP6CM1 were significantly up-regulated in the two selected strains based on real-time fluorescence quantitative PCR results. Other 3 genes, CYP6CX2, CYP6CX4 and CYP6DW3 were only highly expressed in the acetamiprid selected strain instead of the susceptible strain and imidacloprid selected strain. CYP6CM1 showed the highest expression level among all the 13 tested genes. No functional mutation of CYP6CM1 was found by sequence analysis. The possible role of these genes involving the resistance and cross-resistance of the whitefly MEAM1 cryptic species against neonicotinoids was discussed.


Assuntos
Hemípteros , Inseticidas , Animais , China , Sistema Enzimático do Citocromo P-450 , Resistência a Inseticidas , Neonicotinoides , Nitrocompostos
13.
Public Health Nurs ; 37(5): 757-763, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32677072

RESUMO

OBJECTIVE: To explore the experiences of front-line nurses combating the coronavirus disease-2019 epidemic. DESIGN AND SAMPLE: Fifteen front-line nurses caring for COVID-19 patients were recruited from two hospitals in Wuhan, China from January 26 to February 5, 2020. Data were collected through semi-structured individual interviews and analyzed using standard qualitative methods. RESULTS: Four theme categories emerged from the data analysis: (a) "Facing tremendous new challenges and danger"; (b) "Strong pressure because of fear of infection, exhaustion by heavy workloads and stress of nursing seriously ill COVID-19 patients"; (c) "Strong sense of duty and identity as a healthcare provider"; (d) "Rational understanding of the epidemic-the nurses believed that the epidemic would soon be overcome and would like to receive disaster rescue training." CONCLUSIONS: Although the intensive rescue work drained front-line nurses, both physically and emotionally, they showed a spirit of dedication and felt a responsibility to overcome this epidemic. Their experiences provide useful insights into implementing a safer public health emergency rescue system in preparation for future outbreaks of infectious diseases. Specifically, psychological support and humanistic care should be provided to front-line nurses to maintain their well-being, and nationwide emergency rescue training and disaster education should be implemented.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/enfermagem , Epidemias , Recursos Humanos de Enfermagem Hospitalar/psicologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/enfermagem , Adulto , COVID-19 , China/epidemiologia , Feminino , Humanos , Masculino , Recursos Humanos de Enfermagem Hospitalar/estatística & dados numéricos , Pandemias , Pesquisa Qualitativa , Adulto Jovem
14.
World J Microbiol Biotechnol ; 36(2): 33, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060755

RESUMO

Microbiota from herbivore rumen is of great interest for mining glycoside hydrolases for lignocellulosic biomass biorefinement. We previously isolated a highly active but poorly thermostable xylanase (LXY) from a rumen fluid fosmid library of Hu sheep, a local high-reproductive species in China. In this study, we used a universal enzyme-engineering strategy called SpyTag/SpyCatcher molecular cyclization to improve LXY stability via isopeptide-bond-mediated ligation. Both linear and cyclized LXY (L- and C-LXY, respectively) shared similar patterns of optimal pH and temperature, pH stability, and kinetic constants (km and Vmax). However, the C-LXY showed enhanced thermostability, ion stability, and resilience to aggregation and freeze-thaw treatment than L-LXY, without compromise of its catalytic efficiency. Circular dichroism and intrinsic and 8-anilino-1-naphthalenesulfonic acid-binding fluorescence analysis indicated that the cyclized enzyme was more capable of maintaining its secondary and tertiary structures than the linear enzyme. Taken together, these results promote the cyclized enzyme for potential applications in the feed, food, paper pulp, and bioenergy industries.


Assuntos
Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/genética , Engenharia de Proteínas/métodos , Rúmen/enzimologia , Animais , Catálise , Dicroísmo Circular , Ciclização , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Ovinos , Termodinâmica
15.
Zhongguo Zhong Yao Za Zhi ; 45(8): 1824-1832, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32489066

RESUMO

Plant growth regulator is a kind of synthetic pesticide with similar physiological activity to plant hormones. It has been widely used in grain, vegetables, fruits, flowers and other crops, and become an important technical guarantee for high yield, stable yield, high quality and efficient production of crops. In recent years, plant growth regulator is widely used in Chinese herbal medicine production for regulating the growth and development and increasing production of traditional. However the crop is different from general Chinese medicinal materials, the use of plant growth regulator should not only consider the effect of Chinese herbal medicine production, and also pay special attention to the influence of Chinese traditional medicine efficacy and safety. This paper reviewed the application of plant growth regulator in the traditional Chinese medicine, the impact on the quality and safety of Chinese medicinal materials, as well as plant growth regulator of residue limits standards and testing technology, so as to the scientific use of plant growth regulator, to promote Chinese standardization planting, provide the scientific basis to protect the safety of herbal medicine. At present, the indiscriminate use and abuse of plant growth regulators such as Zhuanggenling and bulking element are common in the production of Chinese crude drugs, which has led to a significant decline in the quality of some Chinese crude drugs, and resulted in the dual residual harm to the Chinese crude drugs and the cultivation environment, causing serious safety risks to human health. In the future, it is necessary to strengthen the registration management, use norms and limit standards of plant growth regulators in traditional Chinese medicinal materials, and strengthen the supervision and regulations on the use of fertilizer instead of medicine to avoid pesticide registration and other disorders, so as to provide a basis for the quality and safety monitoring of traditional Chinese medicinal materials. Simultaneously, it is encouraged to reduction or non-application of plant growth regulators in the production of Chinese medicinal materials, especially for traditional Chinese medicine which contains a variety of active ingredients. Therefore, it is actively advocated to cultivate Chinese medicinal materials through organic or ecological method.


Assuntos
Medicamentos de Ervas Chinesas , Plantas Medicinais , Medicina Herbária , Humanos , Medicina Tradicional Chinesa , Fitoterapia , Reguladores de Crescimento de Plantas
16.
Clin Exp Allergy ; 49(6): 770-780, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30675924

RESUMO

BACKGROUND: Depressive symptoms worsen asthma outcomes; however, the mechanism remains largely unexplored. OBJECTIVE: This study aimed to determine whether depressive symptom-associated immune inflammation correlates with impaired bronchodilator response (BDR) and airway inflammatory phenotypes. METHODS: Eligible adults with asthma (n = 198) underwent clinical assessment, sputum induction and blood sampling. Depressive symptoms were defined by scores on the depression subscale of the Hospital Anxiety and Depression Scale (HADS-D). Pre- and post-bronchodilator spirometry was performed for BDR. Airway inflammatory phenotypes were defined by sputum cell counts. CRP, IL-1ß, IL-5, IL-6, IL-8, TNF-α, IFN-γ, CCL17 and CCL22 in serum and sputum were detected. RESULTS: Compared with the non-depressive group (n = 174), the depressive group (n = 24) exhibited impaired BDR (P = 0.032) and increased sputum neutrophils (P = 0.023), which correlated with the HADS-D scores (P = 0.027 and P = 0.029). Levels of IL-1ß, TNF-α and IFN-γ in the serum and those of IL-1ß and IFN-γ in the sputum were elevated in the depressive group compared to those in the non-depressive group (all P < 0.05). Multiple regression models indicated that TNF-α in the sputum and IL-1ß, IL-6 and IFN-γ in both the serum and sputum were inversely associated with BDR; TNF-α in the sputum and IL-1ß in both the serum and sputum were positively correlated with sputum neutrophils. Mediation analyses revealed that IL-1ß and TNF-α in the sputum and IL-1ß in both the serum and sputum mediate the correlations of the HADS-D scores with BDR and sputum neutrophils, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Asthma patients with depressive symptoms present worse asthma control, which is most likely explained by impaired BDR and neutrophilic airway inflammation. IL-1ß and TNF-α, which are two key pro-inflammatory cytokines that mediate the correlation of depressive symptoms with impaired BDR and neutrophilic airway inflammation, may serve as targeted biomarkers in the neuropsychological phenotype of asthma; however, this result needs to be further validated.


Assuntos
Asma/metabolismo , Depressão/metabolismo , Interleucina-1beta/metabolismo , Neutrófilos/metabolismo , Escarro/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Biomarcadores/metabolismo , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Plant Physiol ; 176(3): 2231-2250, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28724620

RESUMO

Plant regeneration is fundamental to basic research and agricultural applications. The regeneration capacity of plants varies largely in different genotypes, but the reason for this variation remains elusive. Here, we identified a novel thioredoxin DCC1 in determining the capacity of shoot regeneration among Arabidopsis (Arabidopsis thaliana) natural variation. Loss of function of DCC1 resulted in inhibited shoot regeneration. DCC1 was expressed mainly in the inner tissues of the callus and encoded a functional thioredoxin that was localized in the mitochondria. DCC1 protein interacted directly with CARBONIC ANHYDRASE2 (CA2), which is an essential subunit of the respiratory chain NADH dehydrogenase complex (Complex I). DCC1 regulated Complex I activity via redox modification of CA2 protein. Mutation of DCC1 or CA2 led to reduced Complex I activity and triggered mitochondrial reactive oxygen species (ROS) production. The increased ROS level regulated shoot regeneration by repressing expression of the genes involved in multiple pathways. Furthermore, linkage disequilibrium analysis indicated that DCC1 was a major determinant of the natural variation in shoot regeneration among Arabidopsis ecotypes. Thus, our study uncovers a novel regulatory mechanism by which thioredoxin-dependent redox modification regulates de novo shoot initiation via the modulation of ROS homeostasis and provides new insights into improving the capacity of plant regeneration.


Assuntos
Arabidopsis/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxinas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Anidrases Carbônicas/genética , Anidrases Carbônicas/metabolismo , Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/metabolismo , Homeostase , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mutação , Brotos de Planta/fisiologia , Plantas Geneticamente Modificadas , Polimorfismo de Nucleotídeo Único , Regeneração/fisiologia , Tiorredoxinas/genética
18.
Anesth Analg ; 129(2): 587-597, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-29863609

RESUMO

BACKGROUND: Neuropathic pain is often associated with depression. Enhancing endocannabinoids by fatty acid amide hydrolase (FAAH) inhibitors relieves neuropathic pain and stress-induced depressive-like behaviors in animal models. However, it is unclear whether FAAH inhibitor can relieve neuropathic pain-induced depression by or not by its antinociceptive effects. METHODS: Adult male Wistar rats with chronic constriction injury (CCI) to the sciatic nerve were treated with the systemic FAAH inhibitor URB597 (5.8 mg·kg·day, intraperitoneally) or peripherally acting FAAH inhibitor URB937 (1.6 mg·kg·d, intraperitoneally; n = 11-12). The treatment was applied from the 15th day after surgery and continued for 15 days. Mechanical withdrawal threshold was examined by Von Frey test before surgery and on the 28th day after CCI. Depressive-like behaviors were evaluated by forced swimming test (FST) and novelty-suppressed feeding (NSF) after 15-day treatment. The levels of anandamide and 2-arachidonoylglycerol in hippocampus were examined by liquid chromatography and mass spectrometry. Hippocampal neurogenesis including proliferation, differentiation, and survival of newborn cells was assessed by immunohistochemistry. RESULTS: After CCI injury, the rats developed significantly nociceptive and depressive-like behaviors, indicated by persistent mechanical hypersensitivity in Von Frey test, significantly prolonged immobility time in FST (sham: 84.2 ± 13.4 seconds versus CCI: 137.9 ± 18.8 seconds; P < .001), and protracted latency to feed in NSF (sham: 133.4 ± 19.4 seconds versus CCI: 234.9 ± 33.5 seconds; P < .001). For the CCI rats receiving treatment, compared to vehicle placebo group, pain threshold was increased by both URB597 (3.1 ± 1.0 vs 11.2 ± 1.2 g; P < .001) and URB937 (3.1 ± 1.0 vs 12.1 ± 1.3 g; P < .001). Immobility time of FST was reduced by URB597 (135.8 ± 16.6 vs 85.3 ± 17.2 seconds; P < .001) but not by URB937 (135.8 ± 16.6 vs 129.6 ± 17.8 seconds; P = .78). Latency to feed in NSF was also reduced by URB597 (235.9 ± 30.5 vs 131.8 ± 19.8 seconds; P < .001) but not by URB937 (235.9 ± 30.5 vs 232.2 ± 33.2 seconds; P = .72). Meanwhile, CCI decreased the number of proliferating cells and reduced survival of new mature neurons in hippocampus. URB597 but not URB937 treatment improved these cellular deficits. CONCLUSIONS: Inhibition of FAAH can improve depressive-like behaviors induced by neuropathic pain independent of its peripheral antinociceptive action. Enhanced neurogenesis in hippocampus might contribute to the antidepressive effects of URB597.


Assuntos
Amidoidrolases/antagonistas & inibidores , Comportamento Animal/efeitos dos fármacos , Benzamidas/farmacologia , Carbamatos/farmacologia , Depressão/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Hipocampo/efeitos dos fármacos , Neuralgia/tratamento farmacológico , Limiar da Dor/efeitos dos fármacos , Amidoidrolases/metabolismo , Animais , Ácidos Araquidônicos/metabolismo , Depressão/enzimologia , Depressão/fisiopatologia , Modelos Animais de Doenças , Endocanabinoides/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Glicerídeos/metabolismo , Hipocampo/enzimologia , Hipocampo/fisiopatologia , Locomoção/efeitos dos fármacos , Masculino , Neuralgia/enzimologia , Neuralgia/fisiopatologia , Neuralgia/psicologia , Neurogênese/efeitos dos fármacos , Alcamidas Poli-Insaturadas/metabolismo , Ratos Wistar , Receptor CB1 de Canabinoide/metabolismo , Transdução de Sinais , Natação
19.
BMC Infect Dis ; 18(1): 271, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29890956

RESUMO

BACKGROUND: Invasive pulmonary aspergillosis (IPA) has been increasingly reported in patients with underlying respiratory diseases (URD). Early diagnosis of IPA is crucial for mortality reduction and improved prognosis, yet remains difficult. Existing diagnostic tools for IPA largely rely on the detection of biomarkers based on serum or bronchoalveolar lavage fluid (BALF), both of which have their limitations. The use of sputum sample is non-invasive, and Aspergillus detection is feasible; however, the usefulness of sputum biomarkers for the diagnosis of IPA, especially in patients with URD, has not been systematically studied. METHODS: This is a prospective diagnostic trial. At least 118 participants will be recruited from respiratory wards and intensive care units. IPA is defined according to the EORTC/MSG criteria modified for patients with URD. Induced sputum and blood will be collected, and BALF will be obtained by bronchoscopy. Sputum biomarkers, including galactomannan, Aspergillus DNA, triacetylfusarinine and bis(methylthio)gliotoxin will be determined, and the presence of a JF5 antigen will be examined with a lateral fluid device. The sensitivity, specificity, negative predictive value, positive predictive value and diagnostic odds ratio will be computed for different biomarkers and compared using the McNemar χ2 test. Receiver operating characteristic analyses will be performed, and the cut-off values will be established. Participants will receive follow-up evaluations at 3 months and 6 months after recruitment. The difference in hospital stay and survival will be analysed, and the relationships between the levels of biomarkers and hospital stay and survival will be analysed via regression models. DISCUSSION: We have developed and verified the feasibility of Aspergillus-related biomarker assays for sputum. The study findings will contribute to a novel look at the diagnostic performance of sputum biomarkers in IPA and provide important insight into the improvement of the early diagnosis of IPA, particularly in patients with URD. TRIAL REGISTRATION: This study has been registered with the Chinese Clinical Trial Registry ( ChiCTR-DPD-16009070 ) on 24th of August 2016.


Assuntos
Aspergilose Pulmonar Invasiva/diagnóstico , Transtornos Respiratórios/microbiologia , Escarro/microbiologia , Biomarcadores/análise , Líquido da Lavagem Broncoalveolar , Broncoscopia , Protocolos Clínicos , Diagnóstico Precoce , Galactose/análogos & derivados , Humanos , Unidades de Terapia Intensiva , Aspergilose Pulmonar Invasiva/complicações , Tempo de Internação , Mananas/análise , Estudos Prospectivos , Curva ROC , Transtornos Respiratórios/complicações , Sensibilidade e Especificidade , Análise de Sobrevida
20.
Nephrology (Carlton) ; 23(8): 728-736, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28667820

RESUMO

AIM: The growing number of patients suffering from chronic renal disease (CKD) is a challenge for the development of innovative therapies. Researchers have studied the therapeutic effects of cell therapy in acute kidney injury (AKI). However, the therapeutic effect of conditional medium (CM) in the CKD models have been rarely reported. Here, we examined the effects of umbilical cord derived-mesenchymal stem cells (hUC-MSCs) CM on renal fibrosis in a rat model of unilateral ureteral obstruction (UUO). METHODS: Animals were randomly divided into three groups: sham-operated, UUO, UUO + CM. CM was administered via the left renal artery after total ligation of the left ureter. Rats were killed after 14 days of obstruction. Histological changes and oxidative stress parameters were assessed. Western blotting and immunohistochemistry analysis were used to measure epithelial-mesenchymal transition (EMT) markers, including epithelial cadherin (E-cadherin), α-smooth muscle actin (α-SMA), tumour necrosis factor-α (TNF-α), Collagen-I, and transforming growth factor ß1 (TGF-ß1). Proliferation and apoptosis of renal tubular epithelial cells (RTEs) were also measured. RESULTS: HucMSC-CM significantly reduced the levels of malondialdehyde (MDA) and reactive oxygen species (ROS), and increased the activity of glutathione (GSH) induced by UUO. Moreover, CM significantly reduced the expression of TGF-ß1, α-SMA, TNF-α and Collagen-I in UUO kidney, promoted the proliferation of RTEs and inhibited its apoptosis. In addition, the increased expression of E-cadherin also reflects the effective improvement of renal interstitial fibrosis. CONCLUSION: This study shows that CM protects UUO-induced kidney damage and therefore could be a potential tool to prevent CKD progression.


Assuntos
Terapia Biológica/métodos , Meios de Cultivo Condicionados/metabolismo , Células Epiteliais/metabolismo , Nefropatias/prevenção & controle , Túbulos Renais/metabolismo , Células-Tronco Mesenquimais/metabolismo , Regeneração , Cordão Umbilical/citologia , Obstrução Ureteral/terapia , Actinas/metabolismo , Animais , Antioxidantes/metabolismo , Apoptose , Caderinas/metabolismo , Proliferação de Células , Células Cultivadas , Colágeno Tipo I/metabolismo , Modelos Animais de Doenças , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal , Fibrose , Humanos , Nefropatias/etiologia , Nefropatias/metabolismo , Nefropatias/patologia , Túbulos Renais/patologia , Masculino , Estresse Oxidativo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Obstrução Ureteral/complicações , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia
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