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1.
Anal Chim Acta ; 1303: 342504, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38609259

RESUMO

BACKGROUND: Food safety has always been a great concern, and the detection of additives is vital to ensuring food safety. Therefore, there is a necessity to develop a method that can quickly and efficiently separate and detect additives in food. High performance liquid chromatography is widely used in the analysis and testing of food additives. Ionic liquids have attracted wide attention in the preparation of high performance liquid chromatography stationary phases owing to their high stability, low vapor pressure and adjustable structure. RESULTS: We developed a novel dicationic imidazole ionic liquid stationary phase for the simultaneous determination of organic preservatives (sodium benzoate, potassium sorbate) and inorganic preservatives (nitrate and nitrite) in foodstuffs under mixed-mode chromatography. The method had the advantages of easy operation, high reproducibility, good linearity and precision. In the detection of these four preservatives, the limit of detection ≤0.4740 mg⋅L-1 and the limit of quantification ≤1.5800 mg⋅L-1. The intra-day and inter-day precision were less than 4.02%, and the recovery rate was 95.90∼100.19 %. At the same time, we also characterized the stationary phase, explored the mechanism and evaluated the chromatographic performance. The stationary phase was able to operate under the mixed mode of reversed phase/hydrophilic interaction/ion exchange chromatography, and it was capable of separating hydrophilic substances, hydrophobic substances, acids, and inorganic anionic substances with good separation efficiency and had high column efficiency. SIGNIFICANCE: In summary, the stationary phase has a promising application in the routine analysis of organic and inorganic preservatives in food. In addition, the stationary phase has good separation ability for hydrophilic, hydrophobic, ionic substances and complex samples, making it a prospective material for chromatographic separation.


Assuntos
Líquidos Iônicos , Reprodutibilidade dos Testes , Imidazóis , Ciclo Celular , Cromatografia Líquida de Alta Pressão
2.
Plants (Basel) ; 13(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38337943

RESUMO

To explore the regulation mechanism of endogenous phytohormones on rhizome bud germination in Cephalostachyum pingbianense, the contents of IAA, ABA, GA, and CTK in seven above- and under-ground bamboo structure components were determined using enzyme-linked immunosorbent assays (ELISA). The results showed that a higher content of IAA, GA, and CTK all year was found in above-ground components and dormant rhizome buds. Meanwhile, a higher ABA content in young shoots and a lower ABA content in the culm base and dormant rhizome buds were detected during the peak period of shooting. The amounts of emerging shoots and the grown bamboo culms were positively correlated with the content of IAA and the ratio of IAA/ABA and (IAA + CTK + GA)/ABA, while they were negatively correlated with the ratio of CTK/IAA in dormant rhizome buds. The all-year high contents of IAA (19-31 ng/g) and ABA (114-144 ng/g) in rhizome buds, as well as interactions among four hormones, may be the key physiological mechanisms to maintain rhizome bud germination throughout the year in C. pingbianense. As C. pingbianense is a special bamboo species of multi-season shoot sprouting, the above results may supplement scientific data for a comprehensive understanding of physiological mechanisms within the bamboo subfamily.

3.
Int J Mol Sci ; 24(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37834114

RESUMO

The interaction between soil microbes and plants has a significant effect on soil microbial structure and function, as well as plant adaptability. However, the effect of soil micro-organisms on ecological adaption and rapid growth of woody bamboos remains unclear. Here, 16S rRNA and ITS rRNA genes of rhizosphere micro-organisms were sequenced, and the soil properties of three different types of Dendrocalamus sinicus were determined at the dormancy and germination stages of rhizome buds. The result showed that each type of D. sinicus preferred to absorb ammonia nitrogen (NH4+-N) rather than nitrate nitrogen (NO3--N) and required more NH4+-N at germination or rapid growth period than during the dormancy period. In total, nitrogen fixation capacity of soil bacteria in the straight type was significantly higher than that in the introduced straight type, while the ureolysis capacity had an opposite trend. Saprophytic fungi were the dominant fungal functional taxa in habitat soils of both straight and introduced straight type. Our findings are of great significance in understanding how soil microbes affect growth and adaptation of woody bamboos, but also for soil management of bamboo forests in red soil.


Assuntos
Rizosfera , Solo , Solo/química , Nitrogênio , RNA Ribossômico 16S/genética , Bactérias/genética , Plantas/genética , Microbiologia do Solo
4.
J Chromatogr A ; 1708: 464340, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37660561

RESUMO

Three structurally similar silane reagents with different terminal groups were prepared and bonded to silica to obtain three structurally similar stationary phases (Sil-Ph-COOH, Sil-Phe and Sil-Ph-NH2). The prepared stationary phases were characterized through elemental analysis (EA) and Fourier Transform Infrared Spectroscopy (FT-IR). These three stationary phases provided acceptable retention repeatability (relative standard deviations between 0.08% and 0.13%) and high column efficiency (7.3 × 104 plates/m for uridine on Sil-Phe). The retention behavior of the three columns was investigated under different chromatographic conditions including different mobile phase ratio, salt concentration, pH etc. The retention mechanisms were explored by linear solvation energy relationships and Van't Hoff plots. Applications in separation under reversed phase liquid chromatography (RPLC), hydrophilic interaction liquid chromatography (HILIC) and ion exchange chromatography (IEC) mode were investigated. The results showed that the retention capacity of the stationary phases with different terminal groups to the analytes is very different, especially for carboxylic acids, because the surface charges of amino groups and carboxyl groups under weakly acidic conditions produce different electrostatic effects with dissociated carboxylic acids. Finally, the Sil-Phe column was employed to detect ibuprofen extracted from pharmaceutical ibuprofen capsules and vitamins extracted from vitamin tablets.


Assuntos
Ibuprofeno , Vitaminas , Cromatografia Líquida de Alta Pressão , Espectroscopia de Infravermelho com Transformada de Fourier , Cromatografia Líquida , Ácidos Carboxílicos
5.
Front Oncol ; 13: 1185240, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37746295

RESUMO

Purpose: To explore the predictive value of multiple immune-inflammatory biomarkers including serum VEGFA and systemic immune-inflammation index (SII) in HER2-negative advanced gastric cancer (AGC) and establish nomograms for predicting the first-line chemotherapeutic efficacy, progression-free survival (PFS) and overall survival (OS) of patients with this fatal disease. Methods: From November 2017 to April 2022, 102 and 34 patients with a diagnosis of HER2-negative AGC at the First Affiliated Hospital of Bengbu Medical College were enrolled as development and validation cohorts, respectively. Univariate and multivariate analyses were performed to evaluate the clinical value of the candidate indicators. The variables were screened using LASSO regression analysis. Predictive models were developed using significant predictors and are displayed as nomograms. Results: Baseline VEGFA expression was significantly higher in HER2-negative AGC patients than in nonneoplastic patients and was associated with malignant serous effusion and therapeutic efficacy (all p<0.001). Multivariate analysis indicated that VEGFA was an independent predictor for first-line therapeutic efficacy and PFS (both p<0.01) and SII was an independent predictor for first-line PFS and OS (both p<0.05) in HER2-negative AGC patients. The therapeutic efficacy model had an R2 of 0.37, a Brier score of 0.15, and a Harrell's C-index of 0.82 in the development cohort and 0.90 in the validation cohort. The decision curve analysis indicated that the model added more net benefits than VEGFA assessment alone. The PFS/OS models had Harrell's C-indexes of 0.71/0.69 in the development cohort and 0.71/0.62 in the validation cohort. Conclusion: The established nomograms integrating serum VEGFA/SII and commonly available baseline characteristics provided satisfactory performance in predicting the therapeutic efficacy and prognosis of HER2-negative AGC patients.

6.
Plant Physiol Biochem ; 201: 107827, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37329689

RESUMO

Woody bamboos are important resource of industrial fibres. Auxin signaling plays a key role in multiple plant developmental processes, as yet the role of auxin/indole acetic acid (Aux/IAA) in culm development of woody bamboos has not been previously characterized. Dendrocalamus sinicus Chia et J. L. Sun is the largest woody bamboo documented in the world. Here, we identified two alleles of DsIAA21 gene (sIAA21 and bIAA21) from the straight- and bent-culm variants of D. sinicus, respectively, and studied how the domains I, i, and II of DsIAA21 affect the gene transcriptional repression. The results showed that bIAA21 expression was rapidly induced by exogenous auxin in D. sinicus. In transgenic tobacco, sIAA21 and bIAA21 mutated in domains i, and II significantly regulated plant architecture and root development. Stem cross sections revealed that parenchyma cells were smaller in transgenic plants than that in wild type plants. Domain i mutation changed the leucine and proline at position 45 to proline and leucine (siaa21L45P and biaa21P45L) strongly repressed cell expansion and root elongation by reducing the gravitropic response. Substitution of isoleucine with valine in domain II of the full length DsIAA21 resulted in dwarf stature in transgenic tobacco plants. Furthermore, the DsIAA21 interacted with auxin response factor 5 (ARF5) in transgenic tobacco plants, suggesting that DsIAA21 might inhibit stem and root elongation via interacting with ARF5. Taken together, our data indicated that DsIAA21 was a negative regulator of plant development and suggested that amino acid differences in domain i of sIAA21 versus bIAA21 affected their response to auxin, and might play a key role in the formation of the bent culm variant in D. sinicus. Our results not only shed a light on the morphogenetic mechanism in D. sinicus, but also provided new insights into versatile function of Aux/IAAs in plants.


Assuntos
Fator V , Nicotiana , Nicotiana/genética , Nicotiana/metabolismo , Fator V/genética , Fator V/metabolismo , Leucina/genética , Leucina/metabolismo , Ácidos Indolacéticos/metabolismo , Mutação/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas
7.
Front Microbiol ; 14: 1055804, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007507

RESUMO

Background: An increasing number of studies have focused on the role of gut microbiota in the treatment of ADHD, but its related molecular mechanisms are not yet clear, and there is still room for development of studies targeting this area. This study analyzes publications from 2012 to 2021 in a comprehensive and multi-faceted visualization, with the aim of grasping the existing research profile and guiding scholars to make more in-depth studies. Methods: The 1,677 articles and 298 review articles on gut microbiota in ADHD were retrieved from the Web of Science Core Collection. CiteSpace, VOSviewer, Microsoft Excel 2019, Scimago Graphica, Bibliometrix and Pajek metrics software were used for visualization and analysis of the included literature. Results: On August 3, 2022, a total of 1975 English-language articles on gut microbiota in ADHD were retrieved from Web of Science Core Collection (WoSCC) from January 2012 to December 2021, with a steady upward trend in the number of articles published in this field over the decade. The top three countries in terms of the number of articles published are the United States, China, and Spain. Meanwhile, CONSEJO SUPERIOR DE INVESTIGACIONES CIENTIFICAS CSIC, UNIV OF CALIFORNIA SYSTEM, and UDICE FRENCH RESEARCH UNIV have made significant contributions in this field. In the analysis of the published journals, PLoS One was not only the first in terms of number of articles published but also the most cited. Wang J was the most prolific author and CAPORASO JG ranked first in terms of co-cited authors. In addition, "Diet rapidly and reproducibly alters the human gut microbiome," published by David LA et al., has the highest citation frequency in this field. The most frequently occurring keyword was "gut microbiota." Conclusion: The results of this paper clarify the current status of research on gut microbiota in ADHD. Based on the research on the mechanism of gut microbiota in other diseases, there is reason to believe that the exploration of gut microbiota in ADHD must be increasingly mature. And the study speculates that future research may focus on "nutrition supplements," "lipid metabolism," and "gut brain axis." It is imperative to promote a closer international cooperation among scholars in this field.

8.
Front Microbiol ; 13: 1033293, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36523824

RESUMO

Compared with the ordinary single-season shooting among woody bamboos in Poaceae, the attribute of full-year shooting in Cephalostachyum pingbianense represents a unique shooting type or mechanism. Nevertheless, except for the overall physiological mechanism, the effect of ecological factors, especially soil microorganisms, on this full-year shooting characteristic remains unclear. In this study, 16S rRNA and ITS rRNA genes were sequenced using the Illumina platform. Our aims were to detect the seasonal changes in rhizospheric microbial communities of C. pingbianense and to discover the correlations of soil microbes with soil properties and bamboo shoot productivity. The results showed that seasonal change had no significant effect on bacterial alpha diversity, but significantly affected bacterial and fungal community structures as well as fungal richness. Among all soil properties examined, soil temperature, soil moisture and organic matter were the predominant factors affecting bacterial community diversity and structure. Soil temperature and soil moisture also significantly influenced fungal community structure, while available phosphorus had the greatest effect on fungal diversity. In each season, bacterial genera Acidothermus, Roseiarcus, and Bradyrhizobium, along with fungal genera Saitozyma, Mortierella, Trichoderma, etc., were dominant in bacterial and fungal communities, respectively. Bacterial community functions in four seasons were dominated by chemoheterotrophy, cellulolysis, and nitrogen fixation. Saprotrophic fungi occupied a high proportion in soil samples of all seasons. In addition, correlation analysis revealed that the bamboo shoot productivity was positively correlated with multiple microbial taxa involved in carbon and nitrogen cycles. It is proposed that highly abundant microbes involved in carbohydrate degradation and nitrogen fixation in the rhizosphere soil may contribute to the attribute of producing bamboo shoots all year round in C. pingbianense. This study is among the few cases revealing the connection between bamboo shooting characteristics and soil microorganisms, and provides new physiological and ecological insights into the forest management of woody bamboos.

9.
PeerJ ; 10: e13847, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935247

RESUMO

Climate change will significantly affect the distribution area of species. Through establishing distribution model, we can simulate the current and future potential distribution range and provide reference for the introduction and cultivation planning of rare or economic plants. Dendrocalamus sinicus, endemic to Yunnan Province of China, is the strongest woody bamboo in the world. In the present study, the MaxEnt model was performed to simulate the distribution of different types of D. sinicus in China and neighboring countries or regions. The results suggested that the suitable distribution range of "straight type", the main type for cultivation and utilization, was 8°-30°N and 73°-122°E under the current climate conditions, while the potential distribution range of "bending type" was 6°-31°N and 79°-109°E. The two most key climate variables associated with distribution of "straight type" were "Temperature Annual Range" with 36.6% contribution rate and "Temperature Seasonality" (32.4%), while "Isothermality" (47.8%) and "Precipitation of Driest Month" (24.8%) for "bending type". Under different climate change scenarios (SSP1-2.6, SSP5-8.5) and periods (2050, 2090), the potential distribution area of the "straight type" were apparently different, indicating that the distribution area of D. sinicus will be affected significantly by climate changes in the future. Our findings would be not only beneficial to understanding limiting factors for natural distribution of D. sinicus, but also helpful for further germplasm conservation, introduction and cultivation planning of this rare woody bamboo.


Assuntos
Mudança Climática , Madeira , China , Temperatura , Previsões
10.
Physiol Plant ; 174(2): e13674, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35306669

RESUMO

Cephalostachyum pingbianense is the only woody bamboo species that can produce bamboo shoots in four seasons under natural conditions. So far, the regulatory mechanism of shoot bud differentiation and development is unknown. In the present study, indole-3-acetic acid (IAA), zeatin riboside (ZR), gibberellin A3 (GA3 ) and abscisic acid (ABA) contents determination, RNA sequencing and differentially expressed gene analysis were performed on dormant rhizome bud (DR), growing rhizome bud (GR), and germinative bud (GB) in each season. The results showed that the contents of IAA and ZR increased while ABA content decreased, and GA3 content was stable during bud transition from dormancy to germination in each season. Moreover, rhizome bud germination was cooperatively regulated by multiple pathways such as carbohydrate metabolism, hormone signal transduction, cell wall biogenesis, temperature response, and water transport. The inferred hub genes among these candidates were identified by protein-protein interaction network analyses, most of which were involved in hormone and carbohydrate metabolism, such as HK and BGLU4 in spring, IDH and GH3 in winter, GPI and talA/talB in summer and autumn. It is speculated that dynamic phytohormone changes and differential expression of these genes promote the release of rhizome bud dormancy and contribute to the phenological characteristics of full-year shooting. Moreover, the rhizome buds of C. pingbianense may not suffer from ecodormancy in winter. These findings would help accumulate knowledge on shooting mechanisms in woody bamboos and provide a physiological insight into germplasm conservation and forest management of C. pingbianense.


Assuntos
Germinação , Rizoma , Ácido Abscísico/metabolismo , Metabolismo dos Carboidratos/genética , Regulação da Expressão Gênica de Plantas/genética , Germinação/genética , Hormônios/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Poaceae/genética , Rizoma/genética
11.
Environ Sci Pollut Res Int ; 29(5): 6526-6537, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34455564

RESUMO

Ectomycorrhizal fungi (EMF), which form symbiotic ectomycorrhiza with tree roots, mediate heavy metal tolerance of host plants. To investigate the roles of EMF in the growth, modulation of oxidative stress, and cadmium (Cd) accumulation and translocation in Quercus acutissima seedlings, ectomycorrhizal seedlings inoculated with Suillus luteus were treated with different Cd concentrations (0.1, and 5 mg kg-1) for 14 days. EMF accelerated seedling growth and Cd accumulation in roots under the highest Cd concentration of 5 mg kg-1. Catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) activities increased in the leaves of ectomycorrhizal seedlings under the highest Cd concentration. Superoxide dismutase (SOD) trended to increase under both Cd concentrations. Although reduced glutathione (GSH) increased after inoculation of EMF under both Cd concentrations, the release of malondialdehyde increased in the leaves and roots under the highest Cd concentration, indicating that the defense role of EMF in Q. acutissima depends on the Cd concentration. These results indicate that EMF mitigate Cd stress by promoting plant growth and nutrient uptake while modulating the antioxidant system to reduce oxidative stress.


Assuntos
Micorrizas , Quercus , Antioxidantes/metabolismo , Cádmio/toxicidade , Catalase/metabolismo , Glutationa/metabolismo , Micorrizas/metabolismo , Estresse Oxidativo , Raízes de Plantas/metabolismo , Quercus/metabolismo , Plântula/metabolismo , Superóxido Dismutase/metabolismo
12.
Heliyon ; 8(12): e12600, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36593818

RESUMO

Transcription factors (TFs) play indispensable roles in plant development and stress responses. As the largest woody bamboo species in the world, Dendrocalamus sinicus is endemic to Yunnan Province, China, and possesses two natural variants characterized by culm shape, namely straight or bent culms. Understanding the transcriptional regulation network of D. sinicus provides a unique opportunity to clarify the growth and development characteristics of woody bamboos. In this study, 10,236 TF transcripts belonging to 57 families were identified from transcriptome data of two variants at different developmental stages, from which we constructed a transcriptional regulatory network and unigene-coding protein-TFs interactive network of culm development for this attractive species. Gene function enrichment analysis revealed that hormone signaling and MAPK signaling pathways were two most enriched pathways in TF-regulated network. Based on PPI analysis, 50 genes interacting with nine TFs were screened as the core regulation components related to culm development. Of them, 18 synergistic genes of seven TFs, including nuclear cap-binding protein subunit 1, transcription factor GTE9-like, and ATP-dependent DNA helicase DDX11 isoform X1, involved in culm-shape variation. Most of these genes would interact with MYB, C3H, and ARF transcription factors. Six members with two each from ARF, C3H, and MYB transcription factor families and six key interacting genes (IAA3, IAA19, leucine-tRNA ligase, nuclear cap-binding protein subunit 1, elongation factor 2, and coiled-coil domain-containing protein 94) cooperate with these transcription factors were differentially expressed at development stage of young culms, and were validated by quantitative PCR. Our results represent a crucial step towards understanding the regulatory mechanisms of TFs involved in culm development and variation of D. sinicus.

13.
J Cancer ; 12(5): 1356-1364, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33531980

RESUMO

Purpose: To evaluate diagnostic and predictive values of the serum vascular endothelial growth factor-A (VEGF-A) level and systemic immune-inflammation index (SII) in small cell lung cancer (SCLC) patients. Methods: From January 2018 to April 2020, we prospectively enrolled 59 untreated SCLC patients in the study group and 50 non-neoplastic patients in the control group. Blood samples were collected at baseline, after the first two cycles of chemotherapy and at progression in the study group and at entry in the control group. Serum VEGF-A was measured by chemiluminescence, SII was calculated based on complete blood count results, and the relationship between the VEGF-A/SII and clinicopathological characteristics, chemotherapeutic efficacy and progression-free survival (PFS) of SCLC patients was analyzed. Results: Baseline serum VEGF-A was significantly higher in SCLC patients than in non-neoplastic patients (P<0.001), while baseline SII was not (P=0.114). There was no correlation between baseline VEGF-A and SII in SCLC patients (P=0.123); however, there was a significant correlation between baseline VEGF-A and disease stage and central nervous system (CNS) metastasis (P=0.021 and P=0.012, respectively), as well as between baseline SII and disease stage and liver metastasis (P=0.026 and P=0.018, respectively). Serum VEGF-A was significantly lower than the pretreatment level after 2 cycles of treatment (P=0.049) but was not different at progression (P=0.247). Baseline VEGF-A was correlated with the treatment response of first-line chemotherapy (P=0.001), while baseline SII was not (P=0.392). Kaplan-Meier survival analysis suggested that the PFS of first-line chemotherapy was significantly longer in the low-VEGF-A group at baseline than the high-VEGF-A group (11.37 vs. 6.17 months, P<0.001). There was a trend toward longer PFS of first-line chemotherapy in the low-SII group at baseline than the high-SII group, but the difference was not significant (12.10 vs. 9.10 months, P>0.050). Univariate and multivariate Cox regression analyses suggested that baseline VEGF-A (HR: 3.443, 95% CI: 1.330-8.908, P=0.011) was an independent prognostic factor for PFS in SCLC patients. Conclusions: Baseline serum VEGF-A and SII are associated with important clinicopathological characteristics of SCLC patients. VEGF-A, but not SII, has the ability of diagnosis and predicting first-line chemotherapeutic efficacy and prognosis in SCLC patients.

15.
Medicine (Baltimore) ; 99(46): e23096, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33181674

RESUMO

Flipped classroom has received much attention in medical education. The aim of this study was to evaluate the efficacy of flipped classroom combing with human anatomy web-based learning system in anatomy education.A total of 89 freshmen in medical specialty were enrolled and randomly allocated into either the experimental group (receiving the flipped classroom with human anatomy web-based learning system, n = 45) or control group (receiving the traditional classroom teaching, n = 44). A pre-quiz and a post-quiz were conducted before and after the classes, respectively. The improvement in scores between groups was compared. A 5-point Likert scale questionnaire was used to evaluate perceptions and experience.The mean pre-quiz scores of the 2 groups were comparable (all P > .05). However, the mean post-quiz score in the experimental group was significantly higher than that in the control group (91.44 ±â€Š6.25 vs 86.13 ±â€Š11.67, P < .05). The results of questionnaires showed that 44 (97.8%) students agreed with flipped classroom combined with human anatomy web-based learning system, 43 (95.6%) students obtained improved study interest in anatomy learning, and 42 (93.3%) students felt that the interactive, applied in-class activities during the class greatly enhanced their learning.Flipped classroom combined with human anatomy web-based learning system can be used as an effective learning tool for anatomy education.


Assuntos
Anatomia/educação , Redes de Comunicação de Computadores , Educação a Distância/métodos , Educação de Graduação em Medicina , Aprendizagem Baseada em Problemas/métodos , Ensino/tendências , Adulto , Currículo/tendências , Educação de Graduação em Medicina/métodos , Educação de Graduação em Medicina/organização & administração , Escolaridade , Feminino , Humanos , Masculino , Modelos Educacionais , Inquéritos e Questionários , Materiais de Ensino
16.
Ann Rheum Dis ; 79(11): 1460-1467, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32737104

RESUMO

OBJECTIVES AND METHODS: With 432 513 samples from UK Biobank dataset, multivariable linear/logistic regression were used to estimate the relationship between psoriasis/psoriatic arthritis (PsA) and estimated bone mineral density (eBMD)/osteoporosis, controlling for potential confounders. Here, confounders were set in three ways: model0 (including age, height, weight, smoking and drinking), model1 (model0 +regular physical activity) and model2 (model1 +medication treatments). The eBMD was derived from heel ultrasound measurement. And 4904 patients with psoriasis and 847 patients with PsA were included in final analysis. Mendelian randomisation (MR) approach was used to evaluate the causal effect between them. RESULTS: Lower eBMD were observed in patients with PsA than in controls in both model0 (ß-coefficient=-0.014, p=0.0006) and model1 (ß-coefficient=-0.013, p=0.002); however, the association disappeared when conditioning on treatment with methotrexate or ciclosporin (model2) (ß-coefficient=-0.005, p=0.28), mediation analysis showed that 63% of the intermediary effect on eBMD was mediated by medication treatment (p<2E-16). Patients with psoriasis without arthritis showed no difference of eBMD compared with controls. Similarly, the significance of higher risk of osteopenia in patients with PsA (OR=1.27, p=0.002 in model0) could be eliminated by conditioning on medication treatment (p=0.244 in model2). Psoriasis without arthritis was not related to osteopenia and osteoporosis. The weighted Genetic Risk Score analysis found that genetically determined psoriasis/PsA were not associated with eBMD (p=0.24 and p=0.88). Finally, MR analysis showed that psoriasis/PsA had no causal effect on eBMD, osteoporosis and fracture. CONCLUSIONS: The effect of PsA on osteoporosis was secondary (eg, medication) but not causal. Under this hypothesis, psoriasis without arthritis was not a risk factor for osteoporosis.


Assuntos
Antirreumáticos/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Osteoporose/epidemiologia , Psoríase/complicações , Psoríase/tratamento farmacológico , Humanos , Análise da Randomização Mendeliana
17.
BMC Plant Biol ; 19(1): 418, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604418

RESUMO

BACKGROUND: So far, little is known in detail about mating systems of woody bamboos. Paternity analysis of offspring improved our understanding of these systems, and contributed to their germplasm conservation and genetic improvement. RESULTS: In this study, a paternity analysis of offspring from two consecutive mass or sporadically flowering events of Dendrocalamus membranaceus and D. sinicus were conducted to determine their mating system and pollen dispersal using the program COLONY based on simple sequence repeat (SSR) markers. Two sporadically flowering populations of D. sinicus (C1, C2) obtained relatively high paternity assignments rates (69.0-71.4%). Meanwhile, among three populations of D. membranaceus, the sporadically flowering population A also had much higher paternity assignments rates (56.4%) than mass flowering populations B1(28.6%) and B2 (42.5%). Both D. membranaceus and D. sinicus had mixed mating systems while their mating patterns were variable depending on pollination conditions. The maximum pollen dispersal distances were 90 m and 4378 m for D. membranaceus and D. sinicus populations, respectively, and the mating distances of these two species focused on ranges of ca. 0-50 m and 0-1500 m, respectively. CONCLUSIONS: These results revealed for the first time variable mating patterns in woody bamboos. This suggests half-sib seeds from the same bamboo clump may have different male parents and it is crucial to clarify genetic origin in woody bamboos' breeding programs. The results also indicate the importance of pollinators in the mating systems of tropical woody bamboos.


Assuntos
Poaceae/fisiologia , Polinização , Marcadores Genéticos , Repetições de Microssatélites , Poaceae/genética , Reprodução/genética , Especificidade da Espécie
18.
Biochimie ; 165: 131-140, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31356846

RESUMO

Swainsonine is a major toxic ingredients of locoweed plants, ingestion of these plants may cause locoism in livestock characterized by extensive cellular vacuolar degeneration of multiple tissues. However, so far, the mechanisms responsible for vacuolar degeneration induced by SW are not known. In this study, we investigated the role of autophagy in SW-induced TCMK-1 cells using Western blotting, transmission electron microscopy, immunofluorescent microscopy and qRT-PCR. The results showed that SW treatment increased the levels of LC3-II. The co-localization of LC3-II and lysosomal protein LAMP-2 results suggested that SW treatment does not interfere with fusion between autophagosome and lysosome. TEM results indicated that SW induced aggregation of the lysosome around the autophagosome. In addition, SW treatment suppressed p-PI3K, p-Akt, p-mTOR, p-p70S6K and p-4EBP1 level. In conclusion, SW induced autophagy via pI3K/AKT/mTOR signaling pathway and revealed the role of autophagy in causing the SW toxicity characterized by the vacuolar degeneration.


Assuntos
Autofagia/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Túbulos Renais/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Swainsonina/toxicidade , Serina-Treonina Quinases TOR/metabolismo , Animais , Linhagem Celular , Células Epiteliais/patologia , Túbulos Renais/patologia , Transdução de Sinais
19.
Environ Sci Pollut Res Int ; 26(19): 19770-19784, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31090001

RESUMO

Cd and Pb are a toxic environmental pollutant, and their elevated concentrations in the waters and soils could exert detriment effects on human health by food chain. In order to evaluate the capacity to heavy metal accumulation and the physiochemical responses of two Salix genotypes, a 35-day hydroponic seedling experiment was implemented with Salix matsudana Koidz. 'Shidi1' (A42) and Salix psammophila C. 'Huangpi1' (A94) under different concentrations of Cd (15 and 30 µM) or Pb (250 and 300 µM). The results showed that the biomass of A94 severely reduced more than that of A42. The accumulation ability of Cd in different plant organs followed the sequence of leaves > roots > stems. Pb primarily accumulated in the roots for both Salix genotypes (54.27 mg g-1 for A42 and 54.52 mg g-1 for A94). Translocation factors based on accumulation (TF') for Cd were more than 8.0, while TF's for Pb were less than 1.0 in both A42 and A94, implying they could be applied in the phytoremediation of Cd-contaminated sites due to their stronger ability to Cd phytoextraction. The stress of Cd or Pb significantly increased malondialdehyde (MDA) contents and increased photosynthetic rates in leaves of two Salix genotypes. Transpiration rates of willow were positively correlated with its Cd translocation. Both catalase (CAT) and peroxidase (POD) activities were suppressed, while the superoxide dismutase (SOD) was boosted with increasing Cd and Pb levels in the leaves and roots of the two willow genotypes, suggesting SOD plays an important role in the removal of ROS. The inconsistency of the changes in enzyme activity suggests that the integrated antioxidative mechanisms regulate the tolerance to Cd and Pb stress.


Assuntos
Antioxidantes/metabolismo , Cádmio/análise , Chumbo/análise , Salix/efeitos dos fármacos , Salix/crescimento & desenvolvimento , Poluentes do Solo/análise , Biodegradação Ambiental , Biomassa , Cádmio/metabolismo , Genótipo , Hidroponia , Chumbo/metabolismo , Salix/metabolismo , Poluentes do Solo/metabolismo
20.
Res Vet Sci ; 124: 317-320, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31030119

RESUMO

Aconitine, a major aconitum alkaloid, is well known for its high toxicity that induces severe arrhythmias and neurological symptoms. One mechanism of aconitine-induced toxic responses is the induction of apoptosis. Apoptosis and autophagy are interconnected processes and the two pathways share critical components. In this study, we investigated the role of autophagy in aconitine-induced toxicity using mouse model. 120 mice were randomly divided into 4 experimental groups (normal saline), low dose group (0.14 µmol/L), medium dose group (0.28 µmol/L) and high dose group (0.56 µmol/ L). 30 mice in each group were administered with aconitine (lavage) for 30 days. The livers were collected for analysis of autophagy-related proteins by Western blotting. The expression of LC3II/LC3I ratio and Beclin 1 were found to increase and then decrease with the highest expression at 10 days and the p62 showed a time-dependent decreases. Autophagy is regulated by the mTOR pathway, we further analyzed the effects of aconitine on this pathway and found aconitine inhibited, phosphorylation of p-PI3K, p-Akt and p-mTOR. The p-p70s6k and p-4EBP1 which are downstream of mTOR were concomitantly decreased. These results suggest that aconitine induce autophagy in mouse liver. The PI3K/Akt/mTOR signaling pathway is involved in the regulation of aconitine-induced autophagy in the liver of mice.


Assuntos
Aconitina/toxicidade , Autofagia/genética , Fígado/efeitos dos fármacos , Transdução de Sinais/genética , Animais , Relação Dose-Resposta a Droga , Feminino , Fígado/fisiologia , Masculino , Camundongos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Agonistas do Canal de Sódio Disparado por Voltagem/toxicidade
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