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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123047, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37392532

RESUMO

Salt stress easily leads to oxidative stress and promotes the catalase (CAT) response in tomato leaves. For the changes in catalase activity in leaf subcells, there is a need for a visual in situ detection method and mechanism analysis. This paper, taking catalase in leaf subcells under salt stress as the starting point, describes the use of microscopic hyperspectral imaging technology to dynamically detect and study catalase activity from a microscopic perspective, and lay the theoretical foundation for exploring the detection limit of catalase activity under salt stress. In this study, a total of 298 microscopic images were obtained under different concentrations of salt stress (0 g/L, 1 g/L, 2 g/L, 3 g/L) in the spectral range of 400-1000 nm. With the increase in salt solution concentration and the advancement of the growth period, the CAT activity value increased. Regions of interest were extracted according to the reflectance of the samples, and the model was established by combining CAT activity. The characteristic wavelength was extracted by five methods (SPA, IVISSA, IRFJ, GAPLSR and CARS), and four models (PLSR, PCR, CNN and LSSVM) were established according to the characteristic wavelengths. The results show that the random sampling (RS) method was better for the selection samples of the correction set and prediction set. Raw wavelengths are optimized as the pretreatment method. The partial least-squares regression model based on the IRFJ method is the best, and the coefficient of correlation (Rp) and root mean square error of the prediction set (RMSEP) are 0.81 and 58.03 U/g, respectively. According to the ratio of microarea area to the area of the macroscopic tomato leaf slice, the Rp and RMSEP of the prediction model for the detection of microarea cells are 0.71 and 23.00 U/g, respectively. Finally, the optimal model was used for quantitative visualization analysis of CAT activity in tomato leaves, and the distribution of CAT activity was consistent with its color trend. The results show that it is feasible to detect the CAT activity in tomato leaves by microhyperspectral imaging combined with stoichiometry.


Assuntos
Solanum lycopersicum , Catalase , Modelos Teóricos , Algoritmos , Espectroscopia de Luz Próxima ao Infravermelho , Análise dos Mínimos Quadrados , Folhas de Planta , Estresse Salino , Aprendizado de Máquina
2.
Front Plant Sci ; 14: 1179009, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37229122

RESUMO

In order to compare and analyze the chloroplast (cp) genomes of tomato germplasms and understand their phylogenetic relationships, the cp genomes of 29 tomato germplasms were sequenced and analyzed in this study. The results showed highly conserved characteristics in structure, number of gene and intron, inverted repeat regions, and repeat sequences among the 29 cp genomes. Moreover, single-nucleotide polymorphism (SNP) loci with high polymorphism located at 17 fragments were selected as candidate SNP markers for future studies. In the phylogenetic tree, the cp genomes of tomatoes were clustered into two major clades, and the genetic relationship between S. pimpinellifolium and S. lycopersicum was very close. In addition, only rps15 showed the highest average K A/K S ratio in the analysis of adaptive evolution, which was strongly positively selected. It may be very important for the study of adaptive evolution and breeding of tomato. In general, this study provides valuable information for further study of phylogenetic relationships, evolution, germplasm identification, and molecular marker-assisted selection breeding of tomato.

3.
Int J Mol Sci ; 24(9)2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37175940

RESUMO

Powdery mildew is a serious problem in tomato production; therefore, the PM-resistant tomato inbred line, '63187', and the susceptible tomato variety, 'Moneymaker (MM)', were used as experimental materials for the combined analysis of transcriptome and widely targeted metabolome on tomato leaves at 0 h post inoculation (hpi), 12 hpi, and 48 hpi. The results indicated that 276 genes were expressed in all treatments, and the K-means cluster analysis showed that these genes were divided into eight classes in '63187' and ten classes in 'MM'. KEGG enrichment showed that amino acid metabolism, signal transduction, energy metabolism, and other secondary metabolites biosynthesis pathways were significantly enriched. Interestingly, the analysis of WRKY family transcription factors (TFs) showed that the expression of four TFs in '63187' increased with no obvious change in 'MM'; and the expression of one TF in 'MM' increased with no obvious change in '63187'. The combined analysis revealed that both phenylpropanoid biosynthesis and flavonoid biosynthesis pathways were enriched in '63187' and 'MM'. In '63187', six metabolites involved in this pathway were downregulated, and four genes were highly expressed, while in 'MM', three metabolites were upregulated, four metabolites were downregulated, and ten genes were highly expressed. These metabolites and genes might be candidates for PM resistance or susceptibility in subsequent studies. These results provide favorable molecular information for the study of the different resistances of tomatoes to PM, and they provide a basis for the breeding of tomato varieties resistant to PM.


Assuntos
Ascomicetos , Solanum lycopersicum , Transcriptoma , Solanum lycopersicum/genética , Ascomicetos/genética , Melhoramento Vegetal , Erysiphe , Metaboloma , Resistência à Doença/genética , Doenças das Plantas/genética
4.
Front Plant Sci ; 13: 949541, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36186008

RESUMO

One of the most significant environmental factors affecting plant growth, development and productivity is salt stress. The damage caused by salt to plants mainly includes ionic, osmotic and secondary stresses, while the plants adapt to salt stress through multiple biochemical and molecular pathways. Tomato (Solanum lycopersicum L.) is one of the most widely cultivated vegetable crops and a model dicot plant. It is moderately sensitive to salinity throughout the period of growth and development. Biotechnological efforts to improve tomato salt tolerance hinge on a synthesized understanding of the mechanisms underlying salinity tolerance. This review provides a comprehensive review of major advances on the mechanisms controlling salt tolerance of tomato in terms of sensing and signaling, adaptive responses, and epigenetic regulation. Additionally, we discussed the potential application of these mechanisms in improving salt tolerance of tomato, including genetic engineering, marker-assisted selection, and eco-sustainable approaches.

5.
Polymers (Basel) ; 14(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35890638

RESUMO

Traditional low-density polyethylene (LDPE) film causes environmental pollution; there is a pressing need to make new bio-based polymers for alternative products, to meet agricultural production needs and for sustainable ecological development. In this study, urea-formaldehyde resin (UF) was modified with polyvinyl alcohol (PVA) and 1-2.5% bio-based sulfonate (BBS). The influence of BBS inducing on the functional groups, microstructure, and thermal behavior was evaluated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). A biodegradable film was prepared with modified UF resin as adhesive and pulp lignocellulose as raw material. The biodegradable mulch film samples were tested for biodegradability, water retention, and cooling soil temperature characters using LDPE and no mulching (NM) as a control. The results showed that with the increase of BBS content, the viscosity and reactivity of modified PUF resin increased, and the free formaldehyde content decreased. A 2%BBS modified PUF resin (2.0BBS/PUF) accelerated the curing process of the PUF resin, formed a flexible macromolecular network structure, and enhanced the toughness of the resin. The biodegradable mulch prepared with PUF, BBS, and 2.0BBS/PUF as adhesives had good water retention. BBS modification increased the degradation rate of mulch by 17.53% compared to the PUF. Three biodegradable films compared with LDPE and NM significantly reduced the soil temperature under summer cucumber cultivation, and the 2.0BBS/PUF coating had the lowest diurnal temperature difference, which provided a suitable soil environment for crop growth.

6.
Arch Microbiol ; 204(8): 521, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35879581

RESUMO

The application of nematicidal microorganisms and their virulence factors provides more opportunities to control root-knot nematodes. Bacillus altitudinis AMCC 1040, previously isolated from suppressive soils, showed significant nematicidal activity, and in this study, nematicidal substances produced by Bacillus altitudinis AMCC 1040 were investigated. The results of the basic properties of active substances showed that these compounds have good thermal stability and passage, are resistant to acidic environment and sensitive to alkaline conditions. Further analysis showed that it is a volatile component. Using HS-SPME-GC/MS, the volatile compounds produced by Bacillus altitudinis AMCC 1040 were identified and grouped into four major categories: ethers, alcohols, ketone, and organic acids, comprising a total of eight molecules. Six of them possess nematicidal activities, including 2,3-butanedione, acetic acid, 2-isopropoxy ethylamine, 3-methylbutyric acid, 2-methylbutyric acid and octanoic acid. Our results further our understanding of the effects of Bacillus altitudinis and its nematicidal metabolites on the management of Meloidogyne incognita and may help in finding less toxic nematicides to control root knot nematodes.


Assuntos
Bacillus , Tylenchoidea , Compostos Orgânicos Voláteis , Animais , Antinematódeos/metabolismo , Antinematódeos/farmacologia , Bacillus/metabolismo , Tylenchoidea/metabolismo , Compostos Orgânicos Voláteis/farmacologia
7.
Plants (Basel) ; 11(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35807574

RESUMO

Due to the increase in the human population, it is necessary to seek efficient methods of increasing crop productivity and, simultaneously, sustaining the soil. One way is to grow high demand crops continuously without rotating with other crops. This practice is often accompanied by increased rates of fertilizer application that can affect efficient nitrogen (N) cycling in the plant rhizosphere soil which, in turn, affects both plant growth and environmental pollution. In the present study, twelve various cucumber soils were selected from monoculture systems presenting different cropping years and divided into two groups including soils with relatively high mineral N (HMN) content (N > 100 mg kg−1 soil) and those with a lower mineral N (LMN) content (N < 100 mg kg−1 soil). All soils were amended with the addition of compost alone or in combination with bacterial inoculation to evaluate their effects on plant growth, microbial numbers, N mineralization, and N cycling genes. In general, the HMN soils increased (p < 0.05) net N mineralization (NNM) but did not statistically (p > 0.05) affect plant biomass compared to the LMN soils; however, compost addition increased both NNM and plant biomass in the HMN soils. In addition, the HMN soils had higher fungal pathogen numbers (FPNs) but lower total microbial biomass (TMB) and bacterial numbers (BNs) compared to the LMN soils; however, compost addition decreased FPNs but increased TMB and BNs in the HMN soils (all p < 0.05). Plant biomass was positively related to TMB, BN and NNM but was negatively related to FPN (all p < 0.05). In summary, compost addition reduced the high mineral N levels' adverse effects on the rhizosphere soil and plant growth.

8.
J Appl Microbiol ; 132(4): 3058-3072, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34826186

RESUMO

AIMS: The effect of Bacillus strains combined with fish protein hydrolysates (FPHs) on cucumber root rot disease, seedlings growth and substrate nutrients was investigated. METHODS AND RESULTS: We isolated three strains capable of mitigating cucumber root rot disease, XY-1 and XY-13 strains were identified as B. amyloliquefaciens, and XY-53 strain as B. subtilis. In the absence of bacteria, The 200×dilution (5 ml L-1 ) of FPHs was the optimum concentration for improving cucumber seedlings growth. In vivo antibiosis tests showed that combined bacteria alongside FPHs inhibited the pathogen growth by 85%~90%, higher than individual bacteria. The FPHs combined either with XY-1 and XY-53 strains or with XY-13 and XY-53 strains promoted seedlings growth under infection, whereas FPHs combined with a mixture of XY-1, XY-13 and XY-53 strains showed the highest total phosphorus and organic matter content in substrate. Moreover, FPHs combined with XY-53 strain increased urease activity, while combined either with XY-13 and XY-53 strains or with XY-1, XY-13 and XY-53 strains increased sucrase activity under infection. CONCLUSIONS: FPHs combined with B. amyloliquefaciens and B. subtilis had great potential to suppress growth of root rot and promote cucumber seedlings and increase substrate nutrient content. SIGNIFICANCE AND IMPACT OF THE STUDY: Co-inoculation of B. amyloliquefaciens and B. subtilis with addition of FPHs is a good strategy for maintaining healthy crops.


Assuntos
Bacillus , Cucumis sativus , Fusarium , Cucumis sativus/microbiologia , Nutrientes , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Raízes de Plantas/microbiologia , Hidrolisados de Proteína/farmacologia , Plântula/microbiologia
9.
Front Bioeng Biotechnol ; 8: 573938, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33163480

RESUMO

AIMS: To investigate the impact of subchondral bone cysts (SBCs) in stress-induced osseous and articular variations in cystic and non-cystic knee models using finite element analysis. MATERIALS AND METHODS: 3D knee joint models were reconstructed from computed tomography (CT) and magnetic resonance imaging (MRI). Duplicate 3D models were also created with a 3D sphere mimicking SBCs in medial tibia. Models were divided into three groups. In group A, a non-cystic knee model was used, whereas in groups B and C, SBCs of 4 and 12 mm size were simulated, respectively. Cyst groups were further divided into three sub-groups. Each of sub-group 1 was composed of a solitary SBC in the anterior half of tibia adjacent to joint line. In sub-group 2, a solitary cyst was modeled at a lower-joint location, and in sub-group 3, two SBCs were used. All models were vertically loaded with weights representing double- and single-leg stances. RESULTS: During single-leg stance, increase in subchondral bone stress in sub-groups B-1 and B-3 were significant (p = 0.044, p = 0.026). However, in sub-group B-2, a slight increase was observed than non-cystic knee model (9.93 ± 1.94 vs. 9.35 ± 1.85; p = 0.254). All the sub-groups in group C showed significantly increased articular stress (p < 0.001). Conversely, a prominent increase in peri-cystic cancellous bone stress was produced by SBCs in groups B and C (p < 0.001). Mean cartilage shear stress in sub-groups B-1 and B-2 (0.66 ± 0.56, 0.58 ± 0.54) was non-significant (p = 0.374, p = 0.590) as compared to non-cystic model (0.47 ± 0.67). But paired cysts of the same size (B-3) produced a mean stress of 0.98 ± 0.49 in affected cartilage (p = 0.011). Models containing 12 mm SBCs experienced a significant increase in cartilage stress (p = 0.001, p = 0.006, p < 0.001) in sub-groups C-1, C-2, and C-3 (1.25 ± 0.69, 1.01 ± 0.54, and 1.26 ± 0.59), respectively. CONCLUSION: The presence of large-sized SBCs produced an increased focal stress effect in articular cartilage. Multiple cysts further deteriorate the condition by increased osseous stress effect and high tendency of peripheral cyst expansion in simulated cystic knee models than non-cystic knee models.

10.
Sci Rep ; 10(1): 18639, 2020 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-33122787

RESUMO

Different fixation modalities are available for fixation of posterior malleolar fractures (PMFs), but the best method is still unclear. The purpose of this study was to carry out a comparative biomechanical analysis of three commonly used fixation constructs for PMFs using experimental and finite element analysis (FEA). 15 human cadaveric ankle specimens were randomly divided into three groups. Specimens in group-A were fixed with two anteroposterior (AP) lag screws, group-B with two posteroanterior (PA) lag screws, and for group-C, a posterior plate was used. Each model was subjected to axial load. Outcomes included loads for 0.5 mm, 1 mm, 1.5 mm, and 2 mm vertical displacements of posterior fragments were noted. 3D FE models were reconstructed from computed tomography (CT) images and subjected to vertical loads. The model's stress, fracture step-off, and resultant strains in implants were also studied in 3D FE models. Significantly higher amounts of mean compressive loads were observed to cause the same amount of vertical displacements in plate group (265 ± 60.21 N, 796 ± 57.27 N, 901.18 ± 8.88 N, 977.26 ± 13.04 N) than AP (102.7 ± 16.78 N, 169.5 ± 19.91 N, 225.32 ± 15.92 N, 269.32 ± 17.29 N) and PA (199.88 ± 31.43 N, 362.80 ± 28.46 N, 431.3 ± 28.12 N, 541.86 ± 36.05 N) lag screws respectively (P < 0.05). Simulated micro-motion analysis demonstrated that fracture step-off values in plate group (0.03 ± 0.001 mm, 0.06 ± 0.003 mm and 0.13 ± 0.010 mm) were the lowest among the three groups (P < 0.001). The cancellous bone showed the highest amount of stress in AP and PA lag groups respectively, whereas the lowest stress was noted in the plate-group. This biomechanical study concluded that posterior plating is biomechanically the most stable fixation construct for PMFs fixation. AP and PA lag screws with higher bone stress and fracture step-off values have a high tendency of bone cut-through and loss of fixation respectively.


Assuntos
Fraturas do Tornozelo/cirurgia , Cadáver , Fixação Interna de Fraturas/métodos , Fraturas do Tornozelo/diagnóstico por imagem , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Tomografia Computadorizada por Raios X/métodos
11.
Plant Physiol Biochem ; 145: 21-33, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31665664

RESUMO

Efficient management and utilization of brackish water irrigation help to minimize yield losses and promote fruit quality and sugar content in tomato fruit. However, the functional genes involved in sugar metabolic pathways and potential molecular pathways responsive to brackish water irrigation remain unknown. To this end, physiological responses and comparative transcriptional profiling was used to analyze the tomato fruit during the white-ripe period (CK1) and mature period (CK2) in plants grown under four water management strategies (rotating irrigation with brackish and fresh water during fruit development, T1; fresh water irrigation, T2; mixed brackish and fresh water irrigation, T3; mixed water and fresh water irrigation in sequence, T4). Comparative analysis revealed that during fruit development (CK2 cv CK1) differentially expressed genes (DEGs) involved in photosynthetic pathways and sucrose-starch metabolism were downregulated. However, two DEGs encoding putative beta-fructofuranosidases were significantly upregulated at the mature stage, which promoted the accumulation of glucose and fructose in CK2. Comparing four types of management strategies, rotating irrigation with brackish water and fresh water (T1) led to reprograming of global gene expression. Moreover, the upregulated DEGs in T1 were significantly enriched for signaling, hormone metabolism, and stress tolerance, suggesting the coordination of both stresses signaling as well as the plant hormone. These results provide a valuable reference for rational use of brackish water in the production of high-quality tomato in arid and semi-arid regions.


Assuntos
Frutas , Regulação da Expressão Gênica de Plantas , Águas Salinas , Solanum lycopersicum , Açúcares , Transcriptoma , Frutas/química , Frutas/genética , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Águas Salinas/farmacologia , Açúcares/análise
12.
Injury ; 50(6): 1247-1255, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31040027

RESUMO

PURPOSE: In this era of life highly comminuted and multi planar tibial plateau fractures involving the posterior corners are more commonly seen and addressed in the literature than before. Among these several types have not been described in the currently used classification systems. In fact simple classification systems ignore several fracture types and leniently grouped the fractures with different mechanism, morphology, treatment modalities and prognosis in same category. On the other hand, more extensive nature classifications with detailed subdivisions are difficult to remember for clinicians. The clinical reliability of these classifications is another problem. All these issues demand the potential need of a new classification. The aim of this study was to describe a quadrant specific two column classification of tibial plateau fractures and to analyse its inter-observer and intra-observer reliability, clinical assessment and application. MATERIALS AND METHODS: From January 2009 to December 2015, 44 patients with tibial plateau fractures were studied retrospectively. The antero-posterior (AP), lateral X-rays and computed tomography (CT) with axial transverse, sagittal, coronal and three dimensional (3D) reconstruction images were performed for all the patients. All of the fractures were categorized according to quadrant specific two column classification and the traditional Schatzker's classification. The comparative analysis for inter-observer and intra-observer reliability of the new classification and the Schatzker's classification was conducted by four observers. RESULTS: Three cases didn't match any type in the Schatzker's classification. While on the other hand, all cases were classified by two column classification. The mean kappa values for inter-observer reliability by using the Schatzker's classification was 0.723 (range, 0.674-0.823), representing substantial agreement, whereas the mean kappa value was 0.939 (range: 0.897-0.974), representing almost perfect agreement according to two column classification. The mean kappa values for intra-observer reliability using the Schatzker's classification and two column classification were 0.789 (range: 0.590-0.864) and 0.955 (range:0.923-0.948) showing substantial agreement and almost perfect agreement. CONCLUSION: The quadrant specific two column classification is anatomically oriented, CT based and clinically valid. The different fracture types according to anatomic location are represented alphanumerically so that treatment matched to specific fracture type (quadrant specific anatomic fixation) for optimal outcomes. Furthermore, it demonstrates higher inter-observer and intra-observer reliability. This classification can be adopted to strengthen the traditional Schatzker's classification, particularly in the multi planar and posteriorly extended plateau fractures. It can be used as a reliable research tool. The database can be used to distinguish different fracture types, individual type incidences, specific treatment and also prognosis. Authors suggest a large multi-centre study.


Assuntos
Fraturas Intra-Articulares/classificação , Radiografia , Fraturas da Tíbia/classificação , Adulto , Idoso , Tomada de Decisão Clínica , Feminino , Fixação Interna de Fraturas , Humanos , Processamento de Imagem Assistida por Computador , Fraturas Intra-Articulares/diagnóstico por imagem , Fraturas Intra-Articulares/cirurgia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/cirurgia
13.
PeerJ ; 7: e6491, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30842901

RESUMO

OBJECTIVE: To investigate the prevalence and risk factors of gastroesophageal reflux disease (GERD) in the Tibet Autonomous Region, China. METHODS: In this cross-sectional study, a stratified random sampling method was used for collecting samples in the Tibet Autonomous Region. A total of 10,000 individuals were selected from October 2016 to June 2017. A previously-published, validated questionnaire including six items related to the symptoms of GERD was used for evaluating GERD. In addition, basic demographic data, lifestyle, dietary habits, medical history and family history of GERD were investigated to identify risk factors of GERD. RESULTS: A total of 5,680 completed questionnaires were collected and analyzed. The prevalence of GERD in this area was 10.8%. Age (30-40 years vs. under 18 years, odds ratio (OR): 3.025; 40-50 years vs. under 18 years, OR: 4.484), education level (high school vs. primary, OR: 0.698; university vs. primary, OR: 2.804), ethnic group (Han vs. Tibetan, OR: 0.230; others vs. Tibetan, OR: 0.304), altitude of residence (4.0-4.5 km vs. 2.5-3.0 km, OR: 2.469), length of residence (<5 years vs. ≥5 years, OR: 2.218), Tibetan sweet tea (yes vs. no, OR: 2.158), Tibetan barley wine (yes vs. no, OR: 1.271), Tibetan dried meat (yes vs. no, OR: 1.278) and staying up late (yes vs. no, OR: 1.223) were significantly (all P < 0.05) and independently associated with GERD. CONCLUSIONS: The prevalence of GERD is high in the Tibet Autonomous Region, China. Geographic conditions, ethnic group and lifestyle are risk factors for GERD.

14.
Mol Cell Endocrinol ; 477: 103-111, 2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-29908223

RESUMO

Neonatal Fc receptor (FcRn) is down-regulated in Hashimoto's thyroiditis (HT) thyrocytes and mediates IgG endocytosis in thyrocytes. The serum distribution of IgG subclasses (of TgAb and TPOAb) differs between HT patients and normal individuals. We aimed to explore the direction and regulation of FcRn-mediated IgG transport in thyrocyte monolayers and the difference between various IgG subclass transport. IgG was transported by FcRn from the basolateral to apical side in the thyrocyte monolayers grown on Transwell filters and the transport was inhibited by IFN-γ and TNF-α. Stimulation by T3 and TSH down-regulated FcRn expression in thyrocytes. IgG1 was transported preferentially over IgG2 and IgG4, which might be related to the differences in FcRn-binding affinities as shown by SPR. FcRn mediates unidirectional IgG transport in thyrocytes in a tissue-specific manner. Down-regulation of FcRn is speculated to play a protective role in HT pathogenesis by mainly reducing IgG1 transport in thyrocytes.


Assuntos
Antígenos de Histocompatibilidade Classe I/metabolismo , Imunoglobulina G/metabolismo , Receptores Fc/metabolismo , Células Epiteliais da Tireoide/metabolismo , Polaridade Celular , Humanos , Interferon gama/farmacologia , Ligação Proteica , Transporte Proteico , Tireoglobulina/metabolismo , Tireotropina/farmacologia , Tiroxina/farmacologia , Tri-Iodotironina/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
15.
Clin Endocrinol (Oxf) ; 88(6): 943-949, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29520804

RESUMO

BACKGROUND: Hashimoto's thyroiditis (HT) with serum IgG4 concentrations greater than 135 mg/dL can be diagnosed as elevated serum IgG4 HT. HT can also be classified into IgG4 HT and non-IgG4 HT based on an immunohistochemistry analysis of IgG4. The aim of our study was to determine the relationship between elevated serum IgG4 HT and IgG4 HT. METHOD: Both thyroid tissues and serum samples stored before pathological examination from 93 patients with HT were collected. The serum levels of IgG, IgG4, TgAb IgG, TgAb IgG4, TPOAb IgG and TPOAb IgG4 were measured by ELISAs. The expression levels of IgG4, IgG and TGF-ß1 in thyroid tissues were detected by immunohistochemistry. RESULTS: Patients with HT were divided into two groups: elevated serum IgG4 HT (n = 12) and nonelevated serum IgG4 HT (n = 81). Hypothyroidism was found in 5 of 12 cases (41.7%) in the elevated serum IgG4 HT group and 10 of 81 cases (12.3%) in the nonelevated serum IgG4 HT group (P = .023). Serologically, there were no significant differences in the levels of TgAb IgG, TPOAb IgG, TgAb IgG4 and TPOAb IgG4 between the two groups, and the expression of TGF-ß1 in thyroid tissues was not significantly different between the groups. Most importantly, the frequency of patients who satisfied the criteria for IgG4 HT diagnosis was comparable (25% vs 20.9%, P = .756). CONCLUSIONS: The measurement of serum IgG4 allows the identification of patients with HT closely associated with hypothyroidism. However, our study demonstrated that elevated serum IgG4 HT is not equivalent to IgG4 HT.


Assuntos
Doença de Hashimoto/sangue , Imunoglobulina G/sangue , Adulto , Fator Ativador de Células B/sangue , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Glândula Tireoide/patologia , Fator de Crescimento Transformador beta1/sangue
16.
Environ Sci Pollut Res Int ; 25(8): 7589-7599, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29282668

RESUMO

Excessive fertilization is a common agricultural practice that has largely reduced soil nutrient retention capacity and led to nutrient leaching in China. To reduce nutrient leaching, in this study, we evaluated the application of biochar, compost, and biochar-compost on soil properties, leaching water quality, and cucumber plant growth in soils with different nutrient levels. In general, the concentrations of nutrients and heavy metals in leaching water were higher under high-nutrient conditions than under low-nutrient conditions. Both biochar and compost efficiently enhanced soil cation exchange capacity (CEC), water holding capacity (WHC), and microbial biomass carbon (MBC), nitrogen (MBN), and phosphorus (MBP), reduced the potential leaching of nutrients and heavy metals, and improved plant growth. The efficiency of biochar and compost in soil CEC, WHC, MBC, MBN, and MBP and plant growth was enhanced when applied jointly. In addition, biochar and biochar-enhanced compost efficiently suppressed plant-parasitic nematode infestation in a soil with high levels of both N and P. Our results suggest that biochar-enhanced compost can reduce the potential environmental risks in excessively fertilized vegetable soils.


Assuntos
Carbono/química , Carvão Vegetal/química , Cucumis sativus/química , Metais Pesados/química , Nitrogênio/análise , Fósforo/análise , Poluentes do Solo/análise , Agricultura , Animais , Biomassa , China , Compostagem , Cucumis sativus/crescimento & desenvolvimento , Nematoides , Nitrogênio/química , Nutrientes , Desenvolvimento Vegetal , Poluentes do Solo/química , Água
17.
Int Immunopharmacol ; 54: 280-285, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29175506

RESUMO

The immune mechanism underlying Hashimoto's thyroiditis (HT) remains unclear. CD26, also known as dipeptidyl peptidase 4 (DPP-4), is a multifunctional molecule involved in the pathophysiology of autoimmune diseases. This study aimed to investigate the role of CD26 in the pathogenesis of HT. Peripheral blood was drawn from 20 healthy controls and 31 HT patients (19 mild HT patients and 12 severe HT patients). Plasma sCD26 concentrations were measured by ELISA, and sCD26 enzymatic activity was assessed using a luciferase-based assay. The expression levels of membrane-bound CD26 were analyzed by flow cytometry. Plasma sCD26 concentrations were lower in HT patients than in healthy controls, although the difference in sCD26 concentrations between the two groups did not reach statistical significance (P=0.07). The percentages of CD8+ T cells and Tc1 cells with CD26 expression were decreased in HT patients compared with those in healthy controls, and the mean fluorescence intensity (MFI) values of CD26 on CD8+ T cells and Tc17 cells in HT patients were significantly lower than in healthy controls (P<0.05). In HT patients, the expression of CD26 on CD8+ T cells and Tc subsets was decreased in the hypothyroidism group compared with that in the euthyroid group (P<0.05). These results suggest that the sCD26 concentrations and membrane-bound CD26 levels on CD8+ T cells are aberrant in HT and that the reduced CD26 expression may be involved in the progression of HT.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Dipeptidil Peptidase 4/metabolismo , Doença de Hashimoto/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Citotóxicos/imunologia , Adulto , Células Cultivadas , Citotoxicidade Imunológica , Dipeptidil Peptidase 4/genética , Progressão da Doença , Regulação para Baixo , Feminino , Humanos , Interleucina-17/metabolismo , Contagem de Linfócitos , Masculino
18.
Mol Cell Endocrinol ; 440: 1-7, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27832986

RESUMO

Inhibitory CD32b receptors on B cells are critical for humoral immunity. The humoral response plays a role in the pathogenesis of Hashimoto's thyroiditis (HT). This study aimed to investigate B cell subset distribution and CD32b expression within these subsets in HT patients. B cell subset distribution and CD32b expression were analyzed in 60 HT patients and 21 healthy donors. Subset distribution and CD32b expression following stimulation with α-Ig and α-CD40 were also assessed. The percentage of double-negative (DN) memory cells was increased in the HT patients, while the expression level of CD32b on DN memory cells was decreased. Redistribution of B cell subsets was detected in response to stimulation with α-Ig. In addition, the expression level of CD32b was reduced following α-CD40 stimulation. These results suggest that abnormal B cell subset distribution and decreased CD32b expression on DN memory cells might be involved in the pathogenesis of HT.


Assuntos
Linfócitos B/imunologia , Regulação para Baixo , Doença de Hashimoto/imunologia , Doença de Hashimoto/metabolismo , Memória Imunológica , Receptores de IgG/metabolismo , Adulto , Citocinas/sangue , Feminino , Doença de Hashimoto/fisiopatologia , Humanos , Iodeto Peroxidase/imunologia , Ativação Linfocitária , Subpopulações de Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade
19.
Int Immunopharmacol ; 40: 332-338, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27668571

RESUMO

Both cellular and humoral responses play important roles in the pathogenesis of Hashimoto's thyroiditis (HT). However, the immunological differences between euthyroid (mild HT) and hypothyroid (severe HT) patients are unknown. This study aimed to investigate the distribution of lymphocyte subsets and cytokine profiles in HT patients with differences in thyroid function. Peripheral blood was drawn from 18 healthy controls and 54 HT patients (33 patients with mild HT, 21 patients with severe HT). The percentages of B cell subsets, T cell subsets and NK cells were analyzed by flow cytometry. The levels of IL-21 and Bcl-6 mRNA were assessed using real-time PCR. The levels of serum IFN-γ, TNF-α, TGF-ß, IL-4, IL-6, IL-10 and a proliferation-inducing ligand (APRIL) were measured by ELISA or cytometric bead array. The percentages of double-negative memory B cells, plasma cells, Tfh cells and Tc17 cells were higher in HT patients than in the healthy controls. The percentages of Tc17 cells and NK cells were higher in the patients with severe HT than in the patients with mild HT. The levels of serum APRIL, IL-6 and IL-10 were higher in the patients with severe HT than in those with mild HT. The percentage of NK cells was positively correlated with TSH levels in the HT patients. Our data indicate that the distribution of lymphocyte subsets and cytokine profiles is aberrant in HT patients, and the increased percentages of Tc17 cells and NK cells and increased cytokine levels might be involved in the progression of HT.


Assuntos
Linfócitos B/imunologia , Doença de Hashimoto/imunologia , Células Matadoras Naturais/imunologia , Subpopulações de Linfócitos/imunologia , Linfócitos T Citotóxicos/imunologia , Células Th17/imunologia , Diferenciação Celular , Linhagem da Célula , Separação Celular , Células Cultivadas , Citocinas/metabolismo , Progressão da Doença , Citometria de Fluxo , Humanos , Memória Imunológica , Fatores de Risco , Tireotropina/metabolismo
20.
Zhonghua Yi Xue Za Zhi ; 96(5): 339-43, 2016 Feb 02.
Artigo em Chinês | MEDLINE | ID: mdl-26875711

RESUMO

OBJECTIVE: To establish the gestational age-specific reference ranges for thyroid-related indicators of pregnant women in our hospital, especially for serum thyroid stimulating hormone (TSH) in the first trimester. METHODS: A total of 548 pregnant women in the first trimester were collected in Peking University First Hospital from June 2013 to April 2014. Among them, 254 pregnant women with single fetus who conformed to the National Academy of Clinical Biochemistry criteria, without adverse pregnancy outcomes and obstetric complications, were enrolled in the current study. To establish their own self-sequential longitudinal reference intervals, serum TSH, total thyroxine (TT4) and free thyroxine (FT4) levels were measured using Siemens detection kits during three different trimesters. Urine iodine (UI) was measured using digestion instrument in some of the pregnant women. RESULTS: The gestational age-specific reference ranges for thyroid-related indicators of pregnant women in our hospital were as follows: in the first trimester: TSH 0.23-4.08 mU/L, TT4 92.59-186.25 nmol/L, FT4 13.36-20.81 pmol/L; in the second trimester: TSH 0.78-4.25 mU/L, TT4 103.20-180.95 nmol/L, FT4 11.57-16.62 pmol/L; in the third trimester: TSH 0.65-4.52 mU/L, TT4 78.20-174.70 nmol/L, FT4 10.01-20.57 pmol/L. The median level of TSH during 7 to 12 weeks of gestational age was lower than that of 4 to 6 weeks, but with no significant statistical difference (P=0.063). The medians of UI during three trimesters of pregnancy were 211.60 µg/L, 195.55 µg/L and 198.65 µg/L, respectively, which were all classified as adequate iodine status. CONCLUSIONS: The gestational age-specific reference ranges for thyroid-related indicators are different from the kits' reference ranges, which are also different among the three trimesters. It may be more reasonable to establish different reference ranges for thyroid-related indicators at 4 to 6 weeks and 7 to 12 weeks in the first trimester separately.


Assuntos
Testes de Função Tireóidea , Glândula Tireoide , Pequim , Feminino , Idade Gestacional , Humanos , Iodo , Gravidez , Complicações na Gravidez , Trimestres da Gravidez , Valores de Referência , Tireotropina , Tiroxina
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