Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 277
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
J Appl Toxicol ; 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32125006

RESUMO

External stressors, especially environmental toxicants can disturb biological homeostasis and thus lead to adverse health effects. However, there is limited understanding of how cells directly exposed to stressors transmit the signals to cells indirectly in contact with stressors. Extracellular vesicles (EVs) are receiving increasing attention as signal transductors between various types of cells in organisms. Cargo in EVs, including RNAs, proteins, lipids, and other signal molecules can be transferred between cells and become critical determining factors of intercellular communication. EVs can be a powerful mediator of environmental stimuli. It has been shown that external stressors reshape the secretion of EVs, modify the composition of EVs, and thus influence the mediating function of EVs. These abnormal EVs can lead to dysfunction of recipient cells, and even the pathogenesis of diseases. In this review, we first summarized current knowledge about the responses of EVs to external stimuli, including chemicals and chemical mixtures. Then we explained how these altered EVs regulate signal pathways in recipient cells, thus mediating physio-pathological responses in detail. The most up-to-date evidence from molecular, cellular, animal and human levels was synthesized to systematically address the mediating roles of EVs. EVs can be regarded as a bridge to link external stressors and internal response. Further toxicological and molecular epidemiological studies are expected to provide further insight into the roles of EVs in toxicology. The gaps in the engulfment of toxicants into EVs are listed as the priority to be solved in future studies.

2.
Chin Med J (Engl) ; (6): 679-686, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32068606

RESUMO

BACKGROUND: Fibroblast-like synoviocytes (FLSs), resident mesenchymal cells of synovial joints, play an important role in the pathogenesis of rheumatoid arthritis (RA). Dickkopf-1 (DKK-1) has been proposed to be a master regulator of bone remodeling in inflammatory arthritis. Here, potential impairation on the activity of FLSs derived from RA to small interfering RNAs (siRNAs) targeting DKK-1 was investigated. METHODS: siRNAs targeting DKK-1 were transfected into FLSs of patients with RA. Interleukin (IL)-1ß, IL-6, IL-8, matrix metalloproteinase (MMP) 2, MMP3, MMP9, transforming growth factor (TGF)-ß1, TGF-ß2 and monocyte chemoattractant protein (MCP)-1 levels in the cell culture supernatant were detected by enzyme-linked immunosorbent assay (ELISA). Invasion assay and H incorporation assay were utilized to investigate the effects of siRNAs targeting DKK-1 on FLSs invasion and cell proliferation, respectively. Western blotting was performed to analyze the expression of nuclear factor (NF)-κB, interleukin-1 receptor-associated kinase (IRAK)1, extracellular regulated protein kinases (ERK)1, Jun N-terminal kinase (JNK) and ß-catenin in FLSs. RESULTS: DKK-1 targeting siRNAs inhibited the expression of DKK-1 in FLSs (P < 0.01). siRNAs induced a significant reduction of the levels of IL-6, IL-8, MMP2, MMP3 and MMP9 in FLSs compared to the control group (P < 0.05). DKK-1 targeting siRNAs inhibited the proliferation and invasion of FLSs (P < 0.05). Important molecules of pro-inflammatory signaling in FLSs, including IRAK1 and ERK1, were decreased by the inhibition of DKK-1 in FLSs. In contrast, ß-catenin, a pivotal downstream molecule of the Wnt signaling pathway was increased. CONCLUSIONS: By inhibiting DKK-1, we were able to inhibit the proliferation, invasion and pro-inflammatory cytokine secretion of FLSs derived from RA, which was mediated by the ERK or the IRAK-1 signaling pathway. These data indicate the application of DKK-1 silencing could be a potential therapeutic approach to RA.

3.
Mol Med Rep ; 21(3): 1043-1050, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31922239

RESUMO

Oxidative stress is a pathophysiological condition resulting in neurotoxicity, which is possibly associated with neurodegenerative disorders. In this study, the antioxidative effects of the antioxidant astaxanthin (AXT) in combination with huperzine A (HupA), which is used as a cholinesterase inhibitor for the treatment of Alzheimer's disease, were investigated. PC12 cells were treated with either tert­butyl hydroperoxide (TBHP), or with the toxic version of ß­amyloid, Aß25­35, to induce oxidative stress and neurotoxicity. Cell viability, morphology, lactate dehydrogenase (LDH) release, intracellular accumulation of reactive oxygen species (ROS), superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were determined, while neuroprotection was also monitored using an MTT assay. It was found that combining AXT with HupA significantly increased the viability of PC12 cells, prevented membrane damage (as measured by LDH release), attenuated intracellular ROS formation, increased SOD activity and decreased the level of MDA after TBHP exposure when compared to these drugs administered alone. Pretreatment with HupA and AXT decreased toxic damage produced by Aß25­35. These data indicated that combining an antioxidant with a cholinesterase inhibitor increases the degree of neuroprotection; with future investigation this could be a potential therapy used to decrease neurotoxicity in the brain.

4.
Environ Sci Pollut Res Int ; 27(9): 9582-9588, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31916176

RESUMO

In this study, crayfish shell was pyrolyzed at 600 °C to obtain an unmodified biochar (CS600). MgCl2 was used as a modifier to pretreat crayfish shell to produce a modified biochar (CS600-MgCl2) under the same pyrolysis conditions. The two biochars were characterized for physicochemical properties and evaluated for lead (Pb2+) sorption ability to determine the modification mechanism. Mono-element batch adsorption experiments were conducted to compare the sorption performances of CS600 and CS600-MgCl2 to Pb2+ in aqueous solutions. All the experiments were carried out at pH of 7. According to the Freundlich-Langmuir model, CS600-MgCl2 had a higher adsorption capacity (152.3 mg/g) than CS600 (134.3 mg/g). FTIR, SEM, XRD, BET, and ICP analyses were applied to inform the interpretation of the mechanism. CS600 was calcium-rich and mainly removed Pb2+ through the ion exchange mechanism by replacing Ca2+ in the biochar. The increased Pb2+ adsorption capacity of CS600-MgCl2 was mainly due to the enlarged specific surface area and the formation of Mg3(OH)5Cl·4H2O on the modified biochar. Findings of this study suggest that both CS600 and CS600-MgCl2 can be used to remove heavy metal ions from wastewater and MgCl2 can improve the sorption performance of biochar.

5.
Lung ; 198(1): 23-29, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31912413

RESUMO

Chronic cough is one of the most common complaints for which patients in China seek medical attention. However, there are no nationwide data on the prevalence and socioeconomic burden of chronic cough. Although approximately 50% of Chinese men smoke, the vast majority of patients presenting for evaluation of chronic cough are never smokers. An equal sex distribution and a middle-aged predominance have been observed in the Chinese chronic cough population, despite demonstration of a higher cough reflex sensitivity in females and older patients. The role of air pollution in the distinct age and sex distribution requires further study. In terms of the etiologies of chronic cough in China, cough-variant asthma, upper airway cough syndrome, nonasthmatic eosinophilic bronchitis, and atopic cough are the most common causes, comprising 75.2% to 87.6% of cases across different regions. Chinese Guidelines for Diagnosis and Treatment of Cough were initially published in 2005, and updated in 2009 and 2016. In addition, the China Cough Coalition was established in 2016. Great progress has been made in both cough-related clinical practice and research in recent years, however, there are still challenges ahead. To facilitate optimal management of chronic cough in China, efforts promoting the dissemination and application of published guidelines will be essential, especially in community-based healthcare and in rural regions. As chronic refractory cough has been identified as a huge challenge to clinicians worldwide, continued international cooperation will be essential in optimizing evaluation and management of chronic cough.

6.
Chemosphere ; 240: 124860, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31542578

RESUMO

In order to increase the adsorption properties of sodium alginate gel beads, a series of SA@PF-beads (sodium alginate-based beads with different amount of pore-forming agent) were prepared with calcium carbonate as the pore forming agent. The experimental results showed that the adsorption capacity of Cu(Ⅱ) increased by at least two times (from 13.69 mg/g to 33.88 mg/g, treated with SA@PF-0 and SA@PF-2.0, respectively) with proper amount of calcium carbonate added, which is economical and effective. In the experiment, SEM was used to measure the morphology of gel beads with different amount of pore-forming agent. FTIR and XPS were used to analyze the variation of functional groups and bond energies in the adsorption process. Adsorption isotherms and kinetics were conducted and showed that the adsorption process was consistent with Langmuir model and Elovich kinetic model. The maximum Langmuir adsorption 229.746 mg/g. The effects of pH, temperature and solid-liquid ratio on adsorption capacity were also investigated. In brief, calcium carbonate is an efficient and convenient pore-forming agent, which can be used to improve the adsorption properties of alginate gel materials.


Assuntos
Alginatos/química , Cobre/isolamento & purificação , Microesferas , Adsorção , Carbonato de Cálcio/química , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura Ambiente , Poluentes Químicos da Água/isolamento & purificação
7.
Int J Syst Evol Microbiol ; 69(11): 3362-3367, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31622228

RESUMO

A novel Gram-stain-negative bacterium, designated as SCSIO 06110T, was isolated from a deep-sea sediment of the West Pacific Ocean. Cells were 0.5-0.8 µm in width and 3.0-4.0 µm in length, spore-forming, rod-shaped with peritrichous flagella. Positive for catalase and urease, negative for oxidase and nitrate reduction. Growth occurred at 15-37 °C, pH 6-9 and 1-5 % (w/v) NaCl, with optimum growth at 28 °C, pH 7 and 3 % (w/v) NaCl. MK-7 was the only menaquinone. The strain possessed diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and two unidentified phospholipids. Iso-C16 : 0, iso-C15 : 0 and iso-C14 : 0 were the major fatty acids. The novel isolate clustered with genera in the family Paenibacillaceae, but formed a separated branch with the closest relative Chengkuizengella sediminis J15A17T (91.1 % sequence similarity) when compared in a phylogenetic analysis of 16S rRNA gene sequences. The DNA G+C content of strain SCSIO 06110T was 38.5 mol%. Based on the polyphasic data presented, a new genus, Longirhabdus gen. nov., is proposed in the family Paenibacillaceae with the type species Longirhabdus pacifica sp. nov. and the type strain SCSIO 06110T (=DSM 105158T=CGMCC 1.16550T).


Assuntos
Bacillales/classificação , Sedimentos Geológicos/microbiologia , Fontes Hidrotermais/microbiologia , Filogenia , Bacillales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Oceano Pacífico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
8.
Nucleic Acid Ther ; 29(6): 359-366, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31513457

RESUMO

Amyloid-ß (Aß) plaque deposits in the brain are considered to be one of the main pathological markers of Alzheimer's disease (AD). The sequential proteolytic cleavage of amyloid precursor protein (APP) by the aspartyl proteases ß-site APP-cleaving enzyme 1 (BACE1) and γ-secretase produces Aß. Therefore, BACE1 inhibition is a very attractive target for the treatment of AD. Our previous work identified a DNA aptamer named A1 that can bind to BACE1 with high affinity and specificity and exhibits a distinct inhibitory effect on BACE1 activity in an AD cell model. The purpose of this research was to test the effect of aptamer A1 in Tg6799 mice. Four-month-old Tg6799 mice were randomly divided into two groups and treated with aptamer A1 and ineffective aptamer A1scr, respectively, by intracerebroventricular injection. Subsequent behavioral experiments showed that treatment with the aptamer A1 improved the cognitive abilities of the AD mice. Western blot indicated that BACE1 and soluble amyloid precursor protein ß (sAPPß) expression significantly decreased in the A1-treated mice. Moreover, aptamer A1 reduced the content of Aß42 and the number and density of senile plaques in AD mice. Therefore, our results indicate that aptamer A1 is a novel specific and potent BACE1 inhibitor and is a promising potential target for the treatment of AD.

9.
Plant Sci ; 287: 110204, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481207

RESUMO

Stripe rust (Yr), caused by the fungal pathogen Puccinia striiformis f. sp. tritici, is a devastating foliar disease of wheat in China. Chinese wheat landraces originating from the middle and lower reaches of the Yangtze River are potential stripe-rust resistance resources. To identify APR genes for stripe-rust resistance, a panel of 188 accessions derived from the middle and lower reaches of the Yangtze River were inoculated with a mixture of Chinese P. striiformis f. sp. tritici races and resistance evaluated under field conditions in five environments at adult-plant stages. Seventy-three accessions showed degrees of stable resistance. Combining phenotypic datasets from multiple field experiments with high-quality Diversity Arrays Technology and simple sequence repeat markers, we detected 21 marker-trait associations spanning 18 quantitative trait loci (QTLs) on chromosomes 1B, 2A, 2B, 3B, 4A, 5A, 5B, 6B, and 6D, respectively. Single QTLs explained 9.67% to 16.14% of the observed phenotypic variation. Nine QTLs co-localized with previously reported Yr genes or genomic regions. The remaining QTLs were potential novel loci associated with adult-stage stripe-rust resistance. Two novel QTLs, QYr.sicau-3B.2 and QYr.sicau-5B.3, located on chromosomes 3B and 5B significantly explained 16.14% and 11.16% of the phenotypic variation, respectively. Haplotype analysis revealed that accessions carrying APR variants or their combinations showed enhanced degrees of resistance. The potentially novel loci or genomic regions associated with adult-stage resistance may be useful to improve stripe-rust resistance in current wheat cultivars and for future isolation of stripe-rust resistance genes.


Assuntos
Basidiomycota/fisiologia , Resistência à Doença/genética , Estudo de Associação Genômica Ampla , Doenças das Plantas/imunologia , Locos de Características Quantitativas/genética , Triticum/genética , China , Loci Gênicos/genética , Marcadores Genéticos/genética , Haplótipos , Repetições de Microssatélites/genética , Fenótipo , Doenças das Plantas/microbiologia , Triticum/imunologia , Triticum/microbiologia
10.
Allergy Asthma Immunol Res ; 11(6): 871-884, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31552721

RESUMO

PURPOSE: An older female predominance has been reported among chronic cough patients in Western countries, which is considered to be associated with a higher cough sensitivity in females. However, the characteristics of Chinese chronic cough patients remain unclear. This study aimed to explore the age and sex distribution as well as their relationship with cough reflex sensitivity to capsaicin in Chinese chronic cough patients. METHODS: We analyzed the demographic features of 1,882 consecutive chronic cough patients who attended our cough clinic in Guangzhou, China. Cough sensitivity to capsaicin, which was defined as the lowest concentration of capsaicin causing 5 coughs or more (C5), was measured in 539 of the 1,882 patients and 68 healthy volunteers. RESULTS: The mean age of the patients was 43.0 ± 13.7 years and patients aged <50 years accounted for more than two-thirds of the study population. Around 87% of the patients were never-smokers. The proportion of females (51.5%) was almost equal to that of males (48.5%). The pattern of the age and sex distribution was consistently reflected within most common causes of chronic cough, while a female predominance was shown in patients with cough-variant asthma and patients aged ≥50 years. Female patients had higher cough sensitivity to capsaicin than male patients (log C5: 1.58 ± 0.84 vs. 2.04 ± 0.84 µmol/L, P = 0.001), and patients aged ≥50 years had higher cough sensitivity to capsaicin than patients aged <50 years. CONCLUSIONS: In China, patients with chronic cough have a roughly equal sex distribution and a middle-aged predominance, irrespective of a higher cough sensitivity to capsaicin in females and older patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02591550.

11.
BMC Genomics ; 20(1): 640, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395029

RESUMO

BACKGROUND: As one of the most important food crops in the world, increasing wheat (Triticum aestivum L.) yield is an urgent task for global food security under the continuous threat of stripe rust (caused by Puccinia striiformis f. sp. tritici) in many regions of the world. Molecular marker-assisted breeding is one of the most efficient ways to increase yield. Here, we identified loci associated to multi-environmental yield-related traits under stripe rust stress in 244 wheat accessions from Sichuan Province through genome-wide association study (GWAS) using 44,059 polymorphic markers from the 55 K single nucleotide polymorphism (SNP) chip. RESULTS: A total of 13 stable quantitative trait loci (QTLs) were found to be highly associating to yield-related traits, including 6 for spike length (SL), 3 for thousand-kernel weight (TKW), 2 for kernel weight per spike (KWPS), and 2 for both TKW and KWPS, in at least two test environments under stripe rust stress conditions. Of them, ten QTLs were overlapped or very close to the reported QTLs, three QTLs, QSL.sicau-1AL, QTKW.sicau-4AL, and QKWPS.sicau-4AL.1, were potentially novel through the physical location comparison with previous QTLs. Further, 21 candidate genes within three potentially novel QTLs were identified, they were mainly involved in the regulation of phytohormone, cell division and proliferation, meristem development, plant or organ development, and carbohydrate transport. CONCLUSIONS: QTLs and candidate genes detected in our study for yield-related traits under stripe rust stress will facilitate elucidating genetic basis of yield-related trait and could be used in marker-assisted selection in wheat yield breeding.


Assuntos
Estudo de Associação Genômica Ampla , Doenças das Plantas/microbiologia , Locos de Características Quantitativas/genética , Estresse Fisiológico/genética , Triticum/genética , Triticum/fisiologia , Basidiomycota/fisiologia , Fenótipo , Polimorfismo de Nucleotídeo Único , Triticum/microbiologia
12.
J Environ Sci (China) ; 84: 21-28, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31284913

RESUMO

It is urgent to explore an effective removal method for perfluorooctanoic acid (PFOA) due to its recalcitrant nature. In this study, a novel chitosan-based hydrogel (CEGH) was prepared with a simple method using chitosan and ethylene glycol through a repeated freezing-thawing procedure. The adsorption of PFOA anions to CEGH agreed well to the Freundlich-Langmuir model with a maximum adsorption capacity as high as 1275.9 mg/g, which is higher than reported values of most adsorbents for PFOA. The adsorption was influenced by experimental conditions. Experimental results showed that the main removal mechanism was the ionic hydrogen bond interaction between carbonyl groups (COO-) of PFOA and protonated amine (NH+) of the CEGH adsorbent. Therefore, CEGH is a very attractive adsorbent that can be used to remove PFOA from water in the future.


Assuntos
Caprilatos/isolamento & purificação , Quitosana/química , Etilenoglicol/química , Fluorcarbonetos/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Hidrogéis , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica
13.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(2): 216-217, 2019 May 07.
Artigo em Chinês | MEDLINE | ID: mdl-31184063

RESUMO

OBJECTIVE: To ascertain the prevalence of Toxoplasma gondii infection in different genders, ages, and ethnic populations of three border regions in Yunnan Province, China, in order to provide the basic data for prevention and control of toxoplasmosis in these areas. METHODS: A total of 561 serum samples were collected from the local hospitals of three border regions of Yunnan Province (222 serum samples from China-Vietnam border region, 170 serum samples from China-Laos border region, and 169 serum samples from China-Myanmar border region) from November 2015 to May 2016. The detection of IgG antibodies of T. gondii was performed by ELISA. RESULTS: In total, 44 (7.84%) of the 561 serum samples were anti-Toxoplasma IgG positive. The positive rates were 8.56% (19/222), 8.82% (15/170) and 5.92% (10/169) in China-Vietnam, China-Laos, and China-Myanmar border regions, respectively. The anti-Toxoplasma IgG positive rates were 5.63%(16/284) in Han, 10.96% (8/73) in Hani, 13.70% (10/73) in Dai, 4.17% (2/48) in Miao, 11.11% (1/9) in Lahu, 7.69% (1/13) in Jinuo, 12.00% (3/25) in Yao, and 11.11% (3/27) in Yi, respectively. The anti-Toxoplasma IgG positive rate in minorities was 10.11%, which was higher than that in Han significantly (χ2 = 3.884, P < 0.05), and the positive rate in Dai was higher than that in Han significantly (χ2 = 5.594, P < 0.05). The anti-Toxoplasma IgG positive rate in the 11-20-year age group was 23.53% (4/17), which was higher than that in the 0-10 [4.23% (3/71)] (χ2 = 4.593, P < 0.05) and 31-40-year groups [4.00% (3/75)] (χ2 = 4.997, P < 0.05). CONCLUSIONS: There are different degrees of T. gondii infection in the human population in the border areas in Yunnan Province, and the risk of infection in ethnic minorities is higher than that in Han nationality. The prevention and control of toxoplasmosis should focus on the minority population.


Assuntos
Toxoplasmose , Anticorpos Antiprotozoários/sangue , China/epidemiologia , Feminino , Humanos , Masculino , Estudos Soroepidemiológicos , Toxoplasma , Toxoplasmose/sangue , Toxoplasmose/epidemiologia , Toxoplasmose/prevenção & controle
14.
Pulm Pharmacol Ther ; 57: 101811, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31176802

RESUMO

Chronic cough is one of the most common complains for patients seeking medical attention in both general practice and respiratory specialist clinics. Cough variant asthma, eosinophilic bronchitis, upper airway cough syndrome, as well as gastro-esophageal reflux disease are common conditions associated with chronic cough, and cough variant asthma, eosinophilic bronchitis account for a higher proportion of patients with chronic cough in China than in Western countries. An older female predominance has been reported in most Western countries, which may be attributed to a higher cough reflex sensitivity in females, especially those post-menopausal females. However, studies conducted in China showed that patients with chronic cough have a nearly similar gender distribution and most of them are in their late 30s or early 40s, despite the similar gender and age difference in cough reflex sensitivity as Western countries. Environmental and occupational exposures, cigarette smoking, unhealthy lifestyle might play a role in the distinct age and gender distribution of Chinese chronic cough patients, yet further study is needed to clarify it.

15.
Chemosphere ; 233: 431-439, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31176907

RESUMO

The transformation of roxarsone (ROX) during UV disinfection with Fe(III) has been investigated. Fe(OH)2+, as the main Fe(III) species at pH = 3, produces HO under UV irradiation leading to the oxidation of ROX. Dissolved oxygen plays a very important role in the continuous conversion of generated Fe2+ to Fe3+, which ensures a Fe(III)-Fe(II) cycle in the system. The presence of Cl-/HCO3-/NO3- has little influence on the ROX transformation, whereas PO43- achieves an obvious inhibitory effect. The transformation of ROX leads to the formation of inorganic arsenic consisting of a much higher amount of As(V) than As(III). LC-MS analysis shows that phenol, o-nitrophenol and arsenic acid were the main transformation products. Both the radical scavenger experiment and electron spin resonance data confirm that the HO is responsible for ROX transformation. The toxic transformation products are found to have potential environmental risks for the natural environment, organisms and human beings.


Assuntos
Desinfecção/métodos , Compostos Férricos/química , Roxarsona , Raios Ultravioleta , Poluentes Químicos da Água , Purificação da Água/métodos , Íons , Oxirredução , Processos Fotoquímicos , Roxarsona/química , Roxarsona/efeitos da radiação , Águas Residuárias/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/efeitos da radiação
16.
Can J Microbiol ; 65(10): 738-749, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31206319

RESUMO

This study explored the differences among various artificial morel cultivations as well as the factors that influence these differences, including soil bacterial community structure, yield, and mineral element contents of ascocarp and the cultivated soil. High-throughput sequencing results revealed that the dominant bacterial phyla in all the samples, including Proteobacteria, Acidobacteria, Chloroflexi, Bacteroides, and Gemmatimonadetes, were found not only in morel soils (experimental group) but also in wheat soil (control group); the highest richness and diversity in the soil bacteria were observed during the primordial differentiation stage. The M6 group exhibited the highest yield (271.8 g/m2) and had an unexpectedly high proportion of Pseudomonas (25.30%) during the primordial differentiation stage, which was 1.77∼194.62 times more than the proportion of Pseudomonas in other samples. Pseudomonas may influence the growth of morel. The mineral element contents of the different soil groups and the ascocarp were determined by electrothermal digestion and inductively coupled plasma mass spectrometry. The results revealed that morel had high enrichment effects on phosphorus (P, bioconcentration factor = 16.83), potassium (K, 2.18), boron (B, 1.47), zinc (Zn, 1.36), copper (Cu, 1.15), and selenium (Se, 2.27). P levels were the highest followed by Se and K, and the mineral element contents in ascocarp were positively correlated with the soil element contents.


Assuntos
Bactérias/isolamento & purificação , Microbiota , Minerais/análise , Microbiologia do Solo , Solo/química
17.
Curr Issues Mol Biol ; 32: 167-200, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31166172

RESUMO

Streptococcus mutans is considered the predominant etiological agent of dental caries with the ability to form biofilm on the tooth surface. And, its abilities to obtain nutrients and metabolize fermentable dietary carbohydrates to produce acids contribute to its pathogenicity. The responses of S. mutans to environmental stresses are essential for its survival and role in cariogenesis. The VicRK system is one of the 13 putative TCS of S. mutans. The conserved functions of the VicRK signal transduction system is the key regulator of bacterial oxidative stress responses, acidification, cell wall metabolism, and biofilm formation. In this paper, it was discussed how the VicRK system regulates S. mutans virulence including bacterial physiological function, operon structure, signal transduction, and even post-transcriptional control in its regulon. Thus, this emerging subspecialty of the VicRK regulatory networks in S. mutans may strengthen our understandings aimed at providing a basis for the prevention of dental caries.

18.
Respir Res ; 20(1): 112, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31170994

RESUMO

BACKGROUND: The differential sensitivity of cough to antitussive therapies implies the existence of heterogeneity in cough hypersensitivity, but how such heterogeneity is expressed across individual patients is poorly understood. We investigated the phenotypes of cough hypersensitivity by examining transient receptor potential ankyrin 1 (TRPA1)- and transient receptor potential vanilloid 1 (TRPV1)-mediated cough sensitivity in patients with chronic refractory cough. METHODS: Using a selective TRPA1 agonist, allyl isothiocyanate (AITC), we established an AITC cough challenge as a measure of TRPA1-mediated cough sensitivity. The AITC cough challenge and the widely used capsaicin (a selective TRPV1 agonist) cough challenge were performed with 250 patients with chronic refractory cough and 56 healthy subjects. The concentration of AITC or capsaicin solution causing at least two (C2) and five coughs (C5) was recorded. Cough sensitivity was expressed as the mean (95% confidence interval) of log C5, and cough hypersensitivity was defined as a log C5 value lower than that of healthy subjects. RESULTS: A distinct concentration-response effect of inhaled AITC was identified both in patients with chronic refractory cough and in healthy subjects. Cough sensitivity to AITC and capsaicin was significantly higher in patients than in healthy subjects (AITC: 2.42 [2.37-2.48] vs 2.72 [2.66-2.78] mM, p = 0.001; capsaicin: 1.87 [1.75-1.98] vs 2.53 [2.36-2.70] µM, p = 0.001) and was higher in females than in males for both healthy subjects and patients (all p < 0.05). Among the 234 patients who completed both challenges, 25 (10.7%) exhibited hypersensitivity to both AITC and capsaicin, 44 (18.8%) showed hypersensitivity to AITC only, 28 (11.9%) showed hypersensitivity to capsaicin only, and 137 (58.6%) exhibited hypersensitivity to neither. Those with TRPA1- and/or TRPV1-mediated hypersensitivity were predominantly female, while those without TRPA1- and TRPV1-mediated hypersensitivity were mainly male. CONCLUSIONS: Four phenotypes of cough hypersensitivity were identified by the activation of TRPV1 and TRPA1 channels, which supports the existence of heterogeneity in cough pathways and provides a new direction for personalized management of chronic refractory cough. TRIAL REGISTRATION: ClinicalTrials.gov NCT02591550 .


Assuntos
Tosse/induzido quimicamente , Tosse/metabolismo , Canal de Cátion TRPA1/metabolismo , Canais de Cátion TRPV/metabolismo , Adulto , Capsaicina/efeitos adversos , Doença Crônica , Feminino , Humanos , Isotiocianatos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Fármacos do Sistema Sensorial/efeitos adversos , Canal de Cátion TRPA1/agonistas , Canais de Cátion TRPV/agonistas
19.
Front Plant Sci ; 10: 596, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31156668

RESUMO

Stripe rust (also known as yellow rust), caused by the pathogen Puccinia striiformis f. sp. tritici (Pst), is a common and serious fungal disease of wheat (Triticum aestivum L.) worldwide. To identify effective stripe rust resistance loci, a genome-wide association study was performed using 152 wheat landraces from the Yellow and Huai River Valleys in China based on Diversity Arrays Technology and simple sequence repeat markers. Phenotypic evaluation of the degree of resistance to stripe rust at the adult-plant stage under field conditions was carried out in five environments. In total, 19 accessions displayed stable, high degrees of resistance to stripe rust development when exposed to mixed races of Pst at the adult-plant stage in multi-environment field assessments. A marker-trait association analysis indicated that 51 loci were significantly associated with adult-plant resistance to stripe rust. These loci included 40 quantitative trait loci (QTL) regions for adult-plant resistance. Twenty identified resistance QTL were linked closely to previously reported yellow rust resistance genes or QTL regions, which were distributed across chromosomes 1B, 1D, 2A, 2B, 3A, 3B, 4A, 4B, 5B, 6B, 7A, 7B, and 7D. Six multi-trait QTL were detected on chromosomes 1B, 1D, 2B, 3A, 3B, and 7D. Twenty QTL were mapped to chromosomes 1D, 2A, 2D, 4B, 5B, 6A, 6B, 6D, 7A, 7B, and 7D, distant from previously identified yellow rust resistance genes. Consequently, these QTL are potentially novel loci for stripe rust resistance. Among the 20 potentially novel QTL, five (QDS.sicau-2A, QIT.sicau-4B, QDS.sicau-4B.2, QDS.sicau-6A.3, and QYr.sicau-7D) were associated with field responses at the adult-plant stage in at least two environments, and may have large effects on stripe rust resistance. The novel effective QTL for adult-plant resistance to stripe rust will improve understanding of the genetic mechanisms that control the spread of stripe rust, and will aid in the molecular marker-assisted selection-based breeding of wheat for stripe rust resistance.

20.
Biol Psychiatry ; 86(2): 131-142, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31076080

RESUMO

BACKGROUND: The basolateral amygdala (BLA) has been widely implicated in the pathophysiology of major depressive disorder. A-kinase anchoring protein 150 (AKAP150) directs kinases and phosphatases to synaptic glutamate receptors, controlling synaptic transmission and plasticity. However, the role of the AKAP150 in the BLA in major depressive disorder remains poorly understood. METHODS: Depressive-like behaviors in C57BL/6J mice were developed by chronic restraint stress (CRS). Mice received either intra-BLA injection of lentivirus-expressing Akap5 short hairpin RNA or Ht-31, a peptide to disrupt the interaction of AKAP150 and protein kinase A (PKA), followed by depressive-like behavioral tests. Alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid glutamate receptor (AMPAR)-mediated miniature excitatory postsynaptic currents were recorded by whole-cell patch-clamp techniques. RESULTS: Chronic stress exposure induced depressive-like behaviors, which were accompanied by an increase in total and synaptic AKAP150 expression in the BLA. Accordingly, CRS facilitated the association of AKAP150 with PKA, but not of calcineurin in the BLA. Intra-BLA infusion of lentivirus-expressing Akap5 short hairpin RNA or Ht-31 prevented depressive-like behaviors and normalized phosphorylation of serine 845 and surface expression of AMPAR subunit 1 (GluA1) in the BLA of CRS mice. Finally, blockage of AKAP150-PKA complex signaling rescued the changes in AMPAR-mediated miniature excitatory postsynaptic currents in depressive-like mice. CONCLUSIONS: These results suggest that AKAP150-PKA directly modulates BLA neuronal synaptic strength, and that AKAP150-PKA-GluA1 streamline signaling complex is responsible for CRS-induced disruption of synaptic AMPAR-mediated transmission and depressive-like behaviors in mice.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA