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1.
J BUON ; 26(5): 1975-1990, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34761608

RESUMO

PURPOSE: Breast cancer is a common malignant tumor in women with a poor prognosis. This study aimed to investigate angiogenesis subtypes of breast cancer and unveil the etiology and molecular features of breast cancer. METHODS: Based on the angiogenesis gene set derived from AmiGO2, and breast cancer data in the Cancer Genome Atlas (TCGA), we define a novel cluster of angiogenesis subtypes for patients by consensus clustering. The gene regulation, immune landscape, molecular characteristics, and clinical features as well as enrichment pathways were explored in the angiogenesis subtypes of breast cancer. RESULTS: Two angiogenesis subtypes were established through consensus clustering, among which subtype1 included 275 patients and subtype2 included 813 patients. A total of 643 differential expressed genes and 109 miRNAs were found between the two subtypes. The gene set enrichment analysis showed that the enriched hallmark pathways in subtype2 were related to the cancer tumorigenesis and breast cancer progression, including estrogen response early estrogen response late, epithelial-mesenchymal transition (EMT), especially angiogenesis. The mutant-allele tumor heterogeneity and tumor mutation burden of non-angiogenesis subtype were significantly higher than that in the angiogenesis subtype. The stroma score, immune score and ESTIMATE score were significantly higher in angiogenesis subtype, while the tumor purity in angiogenesis subtype was considerably lower. Finally, most immune checkpoints were expressed higher in the angiogenesis subtype. CONCLUSIONS: The omics analysis has established a novel angiogenesis subtype of breast cancer and identified the characteristics of the immune microenvironment and genomic alteration of breast cancer. Thus, this angiogenesis subtype might provide new evidence for inhibiting the progression and immunotherapy response in breast cancer.

2.
Med Sci Monit ; 27: e933381, 2021 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-34775462

RESUMO

BACKGROUND Little is known of the changes in lung radiographic characteristics over time in patients recovering from COVID-19. This study analyzed the clinical features and temporal lung radiographic changes in patients with moderate and severe COVID-19 pneumonia who did not require invasive mechanical ventilation during the acute and convalescent periods. MATERIAL AND METHODS The data of 25 patients with COVID-19 pneumonia from January 29, 2020, to November 24, 2020, who did not require invasive mechanical ventilation and who were followed up were retrospectively collected. The 25 patients were divided into severe and moderate groups. Clinical characteristics and computed tomography (CT) manifestations were compared. A total of 121 consecutive thin-slice CT scans were collected at 4 weeks, 2 months, and 5 months after admission to evaluate lung abnormalities in the patients. The CT score was used to assess disease severity. RESULTS The severe group had a lower rate of nucleic acid conversion within 10 days of admission and higher D-dimer, creatine kinase, and lactate dehydrogenase values. In the severe group, hospital stay was longer and hospitalization costs were higher. The average CT score of the severe group peaked in the second week, while the moderate group peaked in the first week and then decreased over time. There were no statistically significant differences in the average CT score between the 2 groups at the 5-month follow-up. CONCLUSIONS The pulmonary lesions of patients recovering from COVID-19 and who do not require invasive mechanical ventilation were gradually absorbed and resolved over time.


Assuntos
COVID-19/diagnóstico por imagem , COVID-19/patologia , Pulmão/diagnóstico por imagem , Pulmão/fisiologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2
3.
Environ Pollut ; 293: 118499, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34793915

RESUMO

Nitrogen management measures (NMMs) such as the application of urease inhibitors (UIs), synthetic nitrification inhibitors (SNIs), and biochar (BC) are commonly used in mitigating nitrogen (N) loss and increasing fertilizer recovery efficiency (FRE) in agriculture. Calcareous soil under rice cropping is characterized by high nitrification potential, N loss risk, and low FRE. Application of SNIs may stimulate NH3 volatilization in high pH soils and the effects of SNIs on FRE are not always positive. BNIs have many advantages over SNIs. Whether combined application of BNI, UI, and BC that can result in a synergistic effect of improving FRE and decreasing N loss in a calcareous soil under rice cropping worth investigating. In this study, we conducted pot experiments to investigate the effects of single and co-application of BNI (methyl 3-(4-hydroxyphenyl) propionate or MHPP, 500 mg kg-1 soil), UI (N-(n-butyl), thiophosphoric triamide or NBPT, 2% of urea-N), or BC (wheat straw, 0.5% (w/w)) with chemical fertilizer on NH3 volatilization, N2O emission, N leaching, crop N uptake, and FRE in a calcareous soil under rice cropping. Our results demonstrated that those NMMs could mitigate NH3 volatilization by 12.5%-26.5%, N2O emission by 62.7%-73.5%, and N leaching loss by 17.5%-49.0%. However, BNI might have a risk of increasing NH3 (5.98%) volatilization loss. Among those NMMs, double inhibitors (BNI plus UI) yielded a synergistic effect that could mitigate N loss to the maximum extent and effectively improve FRE by 25.4%. The mechanisms of the above effects could be partly ascribed to the niche differentiation between the abundance of AOA and AOB and the changed community structure of AOB, which could further influence nitrification and N fate. Our results demonstrated that co-application of BNI and UI with urea is an effective strategy in reducing N loss and improving FRE in a calcareous soil under rice cropping.

4.
Plant Sci ; 312: 111058, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34620452

RESUMO

Uptake and internal transport of micronutrients are essential for plant growth, development, and yield. In this regard, Iron Regulated Transporters (IRTs) from the Zinc Regulated Transporter (ZRT)/IRT-related protein (ZIP) family play an important role in transition metal uptake. Most studies have been focused on IRT1-like proteins in diploid species. Information on IRT1-like proteins in polyploids is limited. Here, we studied the function of TpIRT1A and TpIRT1B homoeologs in a tetraploid crop, Polish wheat (Triticum polonicum L.). Our results highlighted the importance of TpIRT1 in mediating the uptake and translocation of Fe, Mn, Co, and Cd with direct implications for wheat yield potential. Both TpIRT1A and TpIRT1B were located at the plasma membrane and internal vesicle-like organelle in protoplasts of Arabidopsis thaliana L. and increased Cd and Co sensitivity in yeast. The over-expression of TpIRT1B in A. thaliana increased Fe, Mn, Co, and Cd concentration in its tissues and improved plant growth under Fe, Mn, and Co deficiencies, while increased the sensitivity to Cd compared to wild type. Functional analysis of IRT1 homoeologs from tetraploid and diploid ancestral wheat species in yeast disclosed four distinct amino acid residues in TdiIRT1B (T. dicoccum L. (Schrank)) and TtuIRT1B (T. turgidum L.). Together, our results increase the knowledge of IRT1 function in a globally important crop, wheat.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Raízes de Plantas/metabolismo , Fatores de Transcrição/genética , Triticum/genética , Triticum/metabolismo , Transporte Biológico/genética , Transporte Biológico/fisiologia , Cádmio/metabolismo , Proteínas de Transporte de Cátions/genética , Cobalto/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Ferro/metabolismo , Raízes de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Polônia , Fatores de Transcrição/metabolismo , Zinco/metabolismo
5.
Plant Dis ; 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34698515

RESUMO

Stripe rust caused by Puccinia striiformis f. sp. tritici and powdery mildew caused by Blumeria graminis f. sp. tritici are devastating diseases of wheat worldwide. Exploration of new disease-resistant genes from cultivated wheat and wild relatives are the most effective means of reducing the amounts of fungicides applied to combat these diseases. Thinopyrum scirpeum (2n = 4x = 28, EEEE) is an important promising reservoir of useful genes, including stripe rust and powdery mildew resistance, and may be useful for enhancing wheat disease resistance. Here, we characterize a novel wheat-Th. scirpeum disomic substitution line, K16-730-3, and chromosome-specific markers were developed that can be used to trace the Th. scirpeum chromosome or chromosome segments transferred into wheat. Genomic in situ hybridization and fluorescence in situ hybridization analyses indicated that K16-730-3 is a new 4E (4D) chromosomal substitution line. Evaluation of seedling and adult disease responses revealed that K16-730-3 is resistant to stripe rust and powdery mildew. In addition, no obvious difference in grain yield was observed between K16-730-3 and its wheat parents. Genotyping-by-sequencing analyses indicated that 74 polymerase chain reaction -based markers can accurately trace chromosome 4E which were linked to the disease resistance genes in the wheat background. Further marker validation analyses revealed that 13 specific markers can distinguish between the E-genome chromosomes of Th. scirpeum and the chromosomes of other wheat-related species. The new substitution line K16-730-3 carrying the stripe rust and powdery mildew resistance genes will be useful as novel germplasm in breeding for disease resistance. The markers developed in this study can be used in marker-assisted selection for improvement of disease resistance in wheat.

6.
Exp Ther Med ; 22(5): 1343, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34630697

RESUMO

Colorectal cancer (CRC) is a malignant tumor of the gastrointestinal tract and a leading cause of cancer-associated mortality worldwide. Mex-3 RNA binding family member A (MEX3A) promotes the progression of multiple types of cancer, including ovarian and cervical cancer. However, to the best of our knowledge, the role of MEX3A in CRC is not completely understood. Therefore, the present study aimed to investigate the function of MEX3A in CRC. The mRNA and protein expression levels of MEX3A in CRC cells were analyzed using reverse transcription-quantitative PCR and western blotting, respectively. Cell Counting Kit-8 assays were used to measure cell viability. Cell apoptosis and cell cycle distribution were detected via flow cytometry, and CRC cell invasion was analyzed by performing Transwell assays. Moreover, the mitochondrial membrane potential in CRC cells was measured via JC-1 staining. The results of the present study revealed that the expression levels of MEX3A were upregulated in CRC tissues compared with adjacent healthy tissues. MEX3A knockdown notably inhibited CRC cell viability, and induced apoptosis and mitochondrial injury. In addition, MEX3A knockdown markedly induced G1 phase cell cycle arrest in CRC cells via downregulating CDK2 expression. In conclusion, the findings of the present study suggested that MEX3A knockdown may inhibit the tumorigenesis of CRC cells by regulating CDK2 expression. Therefore, MEX3A may serve as a novel target for CRC treatment.

7.
BMC Infect Dis ; 21(1): 1015, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34583653

RESUMO

BACKGROUND: The morbidity of rifampicin/multidrug-resistant tuberculous meningitis (RR/MDR-TBM) has shown an increasing trend globally. Its mortality rate is significantly higher than that of non-rifampicin/multidrug-resistant tuberculous meningitis (NRR/MDR-TBM). This article aimed to explore risk factors related to RR/MDR-TBM, and compare therapeutic effects of linezolid (LZD)- and non-linezolid-containing regimen for RR/MDR-TB patients in Shenzhen city. Furthermore, we aimed to find a better therapy for pathogen-negative TBM with RR/MDR-TBM related risk factors. METHODS: We conducted a retrospective study enrolling 137 hospitalized cases with confirmed TBM from June 2014 to March 2020. All patients were divided into RR/MDR-TBM group (12 cases) and NRR/MDR-TBM group (125 cases) based on GeneXpert MTB/RIF and (or) phenotypic drug susceptibility test results using cerebral spinal fluid (CSF). The risk factors related to RR/MDR-TBM were investigated through comparing clinical and examination features between the two groups. The mortality rate of RR/MDR-TBM patients treated with different regimens was analyzed to compare their respective therapeutic effects. A difference of P < 0.05 was considered statistically significant. RESULTS: Most patients (111/137, 81%) were from southern or southwestern China, and a large proportion (72/137, 52.55%) belonged to migrant workers. 12 cases were RR/MDR-TBM (12/137, 8.8%) while 125 cases were NRR/MDR-TBM (125/137, 91.2%). The proportion of patients having prior TB treatment history in the RR/MDR-TBM group was significantly higher than that of the NRR/MDR-TBM group (6/12 vs. 12/125, 50% vs. 10.5%, P < 0.01). No significant difference was observed on other clinical and examination features between the two groups. Mortality was significantly lower in RR/MDR-TBM patients on linezolid-containing treatment regimen than those who were not (0/7 versus 3/5, 0% versus 60%, P = 0.045). CONCLUSIONS: The main related risk factor of RR/MDR-TBM is the history of anti-tuberculosis treatment. Linezolid-containing regimen appears to lower mortality rate of RR/MDR-TBM significantly in our study. We think Linezolid should be evaluated prospectively in the treatment of RR/MDR-TBM.


Assuntos
Mycobacterium tuberculosis , Tuberculose Meníngea , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/uso terapêutico , China/epidemiologia , Humanos , Linezolida/uso terapêutico , Estudos Retrospectivos , Rifampina/uso terapêutico , Tuberculose Meníngea/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
8.
J Cardiothorac Surg ; 16(1): 260, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521432

RESUMO

INTRODUCTION: Sublobar resection has been widely accepted for treating pure ground-glass opacities (GGOs). As GGOs have good prognosis, preserving postoperative pulmonary function is the major concern in surgery. No studies have yet compared the success rates of pulmonary function reservation between segmentectomy and wedge resection. METHOD: The three-dimensional rebuild of computed tomography (CT) images was performed, the segmentectomy and wedge resection of the GGO in the target segment were simulated, and the area of cut surface was measured, which was important data for successful postoperative pulmonary recruitment maneuvers. RESULT: With equal volumes of tissue removed, segmentectomy and wedge resection showed similar surface area loss for RS4 and RS5, followed by LS7 + 8, LS6 and LS1 + 2 segments. Compared with other segments, wedge resection performed in RS10, LS3, LS10, RS9 and RS7 may lead to a loss of lot more surface area than segmentectomy. CONCLUSION: Wedge resection is suggested for segments RS4, RS5, LS1 + 2 and LS7 + 8, whereas segmentectomy is advised for segments RS1, LS4 + 5 and RS2. Meanwhile, deep wedge resection should be avoided for segments RS8, RS7, RS10, LS3, LS10. RS9 and LS9, in order to preserve a larger lung surface area.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Humanos , Pulmão/diagnóstico por imagem , Pulmão/cirurgia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Tomografia Computadorizada por Raios X
9.
Int Immunopharmacol ; 100: 108143, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34543979

RESUMO

Glial cell line-derived neurotrophic factor (GDNF) has been reported to protect mice from intestinal inflammation, but its anti-inflammatory mechanisms are poorly understood. Here we found that there was a downregulation in intestinal expression of GDNF accompanied by an increase of M1 macrophages in dextran sulfate sodium (DSS)-induced colitis in mice. GDNF treatment could facilitate the macrophages polarization towards the M2-like phenotype in DSS-treated mice and LPS-stimulated RAW264.7 cells, and reduce pro-inflammatory cytokines and increase anti-inflammatory cytokines. Mechanistically, the activation of PI3K/AKT pathway might contribute to the regulation of GDNF on macrophage phenotypes and inflammatory response. Moreover, the administration of GDNF significantly ameliorated colitis in DSS-treated mice, but this benefit of GDNF was diminished by macrophage depletion. Therefore, we propose a new mechanism whereby GDNF suppresses DSS-induced colitis in mice via a macrophage-mediated pathway.

10.
BMC Psychiatry ; 21(1): 474, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34583673

RESUMO

BACKGROUND: This study aimed to examine suicide ideation, suicide attempts, and suicide risk by examining a large sample of Chinese university students and identify the predictive factors, including depressive and anxiety symptoms, for suicide attempt and suicide risk. METHODS: We recruited 6,836 students (aged 18-30) based on all students enrolled in 2016 from one university using cluster sampling. They completed four questionnaires: the Beck Scale for Suicide Ideation and the Suicidal Behaviors Questionnaire-Revised were used to measure suicide risk, and students' depressive/anxiety symptoms were estimated using Patient Health Questionnaire and Generalized Anxiety Disorder Scale. RESULTS: Four major findings emerged. First, 18% of the students showed high suicide ideation, 14.5% showed suicide risk, 18.8% had suicide plans, and 1% had attempted suicide. Second, a weak sense of life's value was common among university students, as 61.4% of students considered suicide as a way to end or evade problems. Third, the results of the binary logistic regression showed that education, suicide ideation, including the wish to die, attitude toward suicide, specificity/planning of suicide, and deception or concealment of contemplated suicide were predictive factors of suicide attempt and suicide risk. The variable "deterrents to active attempt" was also a predictive factor of suicide risk. Fourth, depressive and anxiety symptoms did not significantly predict suicide attempts or suicide risk. Only 10.8% and 5.6% of the students had self-reported scores above the clinical cut-off points for depression and anxiety, respectively. CONCLUSIONS: This study highlighted the prevalence of suicide risk among Chinese university students. The high risk of suicide may not only be due to affective disorders, but also a weak sense of life's value or other reasons. Suicide ideation that significantly predicts suicide risk can be used for suicide risk assessment. Universities should provide appropriate life education and suicide prevention and intervention such as teaching instructors gate-keeper skills.


Assuntos
Tentativa de Suicídio , Universidades , China/epidemiologia , Humanos , Fatores de Risco , Estudantes , Ideação Suicida , Inquéritos e Questionários
11.
Ecotoxicol Environ Saf ; 226: 112825, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34571421

RESUMO

As an essential plant micronutrient, copper (Cu) is required as a component of several enzymes, but it can be highly toxic to plants when present in excess quantities. Nitrogen (N) application can help to alleviate the phytotoxic effects of heavy metals, including Cu, and different N forms significantly affect the uptake and accumulation of heavy metals in plants. The aim of this study was to determine the effects of different N forms, i.e., ammonium (NH4+) and nitrate (NO3-), on Cu detoxification in wheat seedlings. The inhibition of seedling growth under excess Cu was more obvious in wheat plants supplied with NO3- than in those supplied with NH4+. This growth inhibition was directly induced by excess Cu accumulation and reduced absorption of other mineral nutrients by the plants. Compared with seedlings treated with NO3-, those treated with NH4+ showed a decrease in Cu-induced toxicity as a result of increased antioxidant capacity in the leaves and a lower redox potential in the rhizosphere. Furthermore, treatment with NH4+ decreased the loss of mineral nutrients in wheat seedlings exposed to excess Cu. In conclusion, compared with supplying NO3-, supplying NH4+ to wheat seedlings under Cu stress improved their ability to maintain their nutritional and redox balance and increased their antioxidant capacity, thereby preventing a decline in photosynthesis. According to our results, NH4+ is more effective than NO3- in reducing Cu phytotoxicity in wheat seedlings.


Assuntos
Compostos de Amônio , Plântula , Cobre/toxicidade , Homeostase , Nitratos/toxicidade , Nitrogênio , Oxirredução , Fotossíntese , Raízes de Plantas , Triticum
12.
Genomics ; 113(5): 3415-3429, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34371100

RESUMO

UDP-glycosyltransferases (UGTs) are widely involved in plant growth and stress responses. However, UGT family are not well understood in cassava. Here, we identified 121 MeUGT genes and classified them into 14 subfamilies by phylogenetic analysis. All MeUGT proteins have typical feature of the UGTs family. Tandem duplications are the crucial driving force for the expansion of MeUGT family. Cis-Acting elements analysis uncovered those 14 kinds of cis-elements associated with biotic and abiotic stress responses. Transcriptomic and qRT-PCR analyses indicated that MeUGT genes participate in postharvest physiological deterioration of storage root and the responses of biotic and abiotic stresses. Of which, MeUGT-14/41 were significantly induced after Xam treatment. Silencing of MeUGT-14 or MeUGT-41 reduced cassava resistance to Xam, verifying the accuracy of transcriptomic data for function prediction. Together, this study characterized the MeUGTs family and revealed their potential functions, which build a solid foundation for MeUGTs associated genetic improvement of cassava.

13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(4): 1266-1270, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34362514

RESUMO

OBJECTIVE: To analyze the genotypes and distribution of thalassemia in children in Quanzhou Region so as to provide reference for the prevention and control of thalassemia. METHODS: A total of 1 302 children with suspected thalassemia were collected from January 2014 to April 2020 in Quanzhou Region. The deletional α-thalassemia was detected by Gap-PCR, and DNA reverse dot blot (RDB) hybridization was used to detect α- and ß-thalassemia mutations. RESULTS: In the 1 302 cases, 667 cases were identified as thalassemia carriers, and the positive detection rate was about 51.23%. Among them, 380 cases of α-thalassemia gene were detected, and --SEA/αα was the most common genotype with the composition rate about 69.21%. Forty-two cases were identified as HbH disease, and -α3.7/--SEA was the most common genotype. While, 274 cases were identified as ß-thalassemia, and ßIVS-Ⅱ-654/ßN (35.40%) and ßCD41-42/ßN (33.94%) were the most common genotypes. Seventeen cases of ß-thalassemia major/intermedia were identified, and the most common genotypes were ßIVS-Ⅱ-654/ßIVS-Ⅱ-654 and ßIVS-Ⅱ-654/ßCD17. Meanwhile, 13 cases of α- complex ß- thalassemia were detected. Among them, 1 case of ß-thalassemia gene rare mutation Term CD+32 was firstly detected in Fujian Province, and 1 case of CD14-15 mutation was firstly detected in Quanzhou Region. In addition, 3 cases of abnormal hemoglobin disease were identified, in which 2 cases were Hb Q-Thailand and 1 case was Hb G-Honolulu. CONCLUSION: There are various genotypes of thalassemia in children in Quanzhou Region, and many children with thalassemia major or intermedia. Therefore, further prevention and control of thalassemia need to be strengthened for reducing the birth of thalassemia major or intermedia.


Assuntos
Talassemia alfa , Talassemia beta , Criança , China , Testes Genéticos , Genótipo , Heterozigoto , Humanos , Mutação , Talassemia alfa/genética , Talassemia beta/genética
14.
Nat Plants ; 7(9): 1276-1287, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34354259

RESUMO

Stem cell populations in all multicellular organisms are situated in a niche, which is a special microenvironment that defines stem cell fate. The interplay between stem cells and their niches is crucial for stem cell maintenance. Here, we show that an endogenous stress-related signal (ESS) is overrepresented in the shoot stem cell niche under natural growth conditions, and the vast majority of known stem-cell-specific and niche-specific genes responded to stress signals. Interference with the ESS in the stem cell niche by blocking ethylene signalling impaired stem cell maintenance. Ethylene-insensitive 3 (EIN3), the key transcription factor in ethylene signalling, directly actives the expression of the stress hub transcription factor AGAMOUS-LIKE 22 (AGL22) in the stem cell niche and relays ESS signals to the WUSCHEL/CLAVATA network. Our results provide a mechanistic framework for ESS signalling control of the stem cell niche and demonstrate that plant stem cells are maintained by a native stress microenvironment in vivo.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Diferenciação Celular/genética , Meristema/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/genética , Receptores de Superfície Celular/genética , Arabidopsis/genética , Diferenciação Celular/fisiologia , Proliferação de Células/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Meristema/genética , Transdução de Sinais , Estresse Fisiológico
15.
Sci Robot ; 6(57)2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34433656

RESUMO

Fibers capable of generating axial contraction are commonly seen in nature and engineering applications. Despite the broad applications of fiber actuators, it is still very challenging to fabricate fiber actuators with combined large actuation strain, fast response speed, and high power density. Here, we report the fabrication of a liquid crystal elastomer (LCE) microfiber actuators using a facile electrospinning technique. Owing to the extremely small size of the LCE microfibers, they can generate large actuation strain (~60 percent) with a fast response speed (<0.2 second) and a high power density (400 watts per kilogram), resulting from the nematic-isotropic phase transition of liquid crystal mesogens. Moreover, no performance degradation is detected in the LCE microfibers after 106 cycles of loading and unloading with the maximum strain of 20 percent at high temperature (90 degree Celsius). The small diameter of the LCE microfiber also results in a self-oscillatory behavior in a steady temperature field. In addition, with a polydopamine coating layer, the actuation of the electrospun LCE microfiber can be precisely and remotely controlled by a near-infrared laser through photothermal effect. Using the electrospun LCE microfiber actuator, we have successfully constructed a microtweezer, a microrobot, and a light-powered microfluidic pump.

16.
Food Chem ; 365: 130615, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34329877

RESUMO

Chiral volatile compounds are known to be distributed in teas at various enantiomeric ratios. However, the performance of each enantiomer, including aroma characteristics, aroma intensities, and contribution to the overall flavor of tea, is still unclear. In this study, aroma characteristics and intensities of 38 volatile enantiomers in standards and baked green teas with chestnut-like aroma and clean aroma were evaluated by an efficient sequential headspace-stir bar sorptive extraction (seq-HS-SBSE) approach combined with the enantioselective gas chromatography-olfactometry/mass spectrometry (Es-GC-O/MS) technique. Moreover, aroma recombination results for the two types of baked green teas using 14 chiral odorants and four achiral odorants indicated that the combinations of the detected odorants mainly contributed to the "floral", "sweet", and "chestnut-like" aromas. R-Linalool simultaneously enhanced the "floral", "sweet", and "chestnut-like" aromas; R-limonene mainly contributed to the "sweet" and "clean" aromas; and S-α-terpineol promoted the "sweet" and "floral" aromas of baked green tea.


Assuntos
Odorantes , Compostos Orgânicos Voláteis , Aromatizantes , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Olfatometria , Chá , Compostos Orgânicos Voláteis/análise
17.
Chemosphere ; 285: 131539, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34329142

RESUMO

In this study, a novel biochar-supported zero-valent iron (ZVI) composite was synthesised by a one-pot co-pyrolysis reduction method, and was used to remove Cu(II) and Cr(VI). The raw materials for the composite were derived from natural bagasse/straw and goethite. Scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, Fourier-transform infrared (FTIR) spectroscopy, thermogravimetry (TG), and Brunauer-Emmett-Teller (BET) analysis were used to characterise the biochar and biochar-supported ZVI composites. Batch removal experiments on the effects of the initial pH and citric acid concentrations were performed as well as kinetic studies and isotherm experiments. The composite materials showed better Cu(II) and Cr(VI) removal performance than single biochar and mineral. The removal of Cu(II) and Cr(VI) is pH-dependent, and proceeds via heterogeneous multilayer chemisorption. Electrochemical analysis revealed that straw biochar-supported ZVI composite exhibited greater electrical conductivity and electron transfer rate than pure biochar and ZVI. FTIR spectroscopy and X-ray photoelectron spectroscopy (XPS) elucidated the uptake mechanism, showing that Cu(II) and Cr(VI) were easily adsorbed onto the biochar surface and were then reduced by ZVI. These results indicate that biochar-supported ZVI composite is effective for heavy metal remediation, which is economical, environment-friendly, and suitable for mass production.


Assuntos
Ferro , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Cromo/análise , Compostos de Ferro , Cinética , Minerais , Poluentes Químicos da Água/análise
18.
Biol Psychiatry ; 90(9): 611-620, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34304866

RESUMO

BACKGROUND: Polygenic scores (PGSs), which assess the genetic risk of individuals for a disease, are calculated as a weighted count of risk alleles identified in genome-wide association studies. PGS methods differ in which DNA variants are included and the weights assigned to them; some require an independent tuning sample to help inform these choices. PGSs are evaluated in independent target cohorts with known disease status. Variability between target cohorts is observed in applications to real data sets, which could reflect a number of factors, e.g., phenotype definition or technical factors. METHODS: The Psychiatric Genomics Consortium Working Groups for schizophrenia and major depressive disorder bring together many independently collected case-control cohorts. We used these resources (31,328 schizophrenia cases, 41,191 controls; 248,750 major depressive disorder cases, 563,184 controls) in repeated application of leave-one-cohort-out meta-analyses, each used to calculate and evaluate PGS in the left-out (target) cohort. Ten PGS methods (the baseline PC+T method and 9 methods that model genetic architecture more formally: SBLUP, LDpred2-Inf, LDpred-funct, LDpred2, Lassosum, PRS-CS, PRS-CS-auto, SBayesR, MegaPRS) were compared. RESULTS: Compared with PC+T, the other 9 methods gave higher prediction statistics, MegaPRS, LDPred2, and SBayesR significantly so, explaining up to 9.2% variance in liability for schizophrenia across 30 target cohorts, an increase of 44%. For major depressive disorder across 26 target cohorts, these statistics were 3.5% and 59%, respectively. CONCLUSIONS: Although the methods that more formally model genetic architecture have similar performance, MegaPRS, LDpred2, and SBayesR rank highest in most comparisons and are recommended in applications to psychiatric disorders.


Assuntos
Transtorno Depressivo Maior , Transtornos Mentais , Esquizofrenia , Transtorno Depressivo Maior/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Transtornos Mentais/genética , Herança Multifatorial , Esquizofrenia/genética
19.
Environ Pollut ; 286: 117575, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34130116

RESUMO

High cadmium (Cd) concentration in common wheat (Triticum aestivum L.) grains poses potential health risks. Several management strategies have been used to reduce grain Cd concentration. However, limited information is available on the use of ammonium-nitrogen (NH4+-N) as a strategy to manage Cd concentration in wheat grains. In this study, NH4+-N addition at the seedling stage unchanged the grain Cd concentration in the high-Cd accumulator, Zhoumai 18 (ZM18), but dramatically increased that in the low-Cd accumulator, Yunmai 51 (YM51). Further analysis revealed that the effects of NH4+-N addition on whole-plant Cd absorption, root-to-shoot Cd translocation, and shoot-to-grain Cd remobilization were different between the two wheat cultivars. In ZM18, NH4+-N addition did not change whole-plant Cd absorption, but inhibited root-to-shoot Cd translocation and Cd remobilization from lower internodes, lower leaves, node 1, and internode 1 to grains via the down-regulation of yellow stripe-like transporters (YSL), zinc transporters (ZIP5, ZIP7, and ZIP10), and heavy-metal transporting ATPases (HMA2). This inhibition decreased the grain Cd content by 29.62%, which was consistent with the decrease of the grain dry weight by 23.26%, leading to unchanged grain Cd concentration in ZM18. However, in YM51, NH4+-N addition promoted continuous Cd absorption during grain filling, root-to-shoot Cd translocation and whole-plant Cd absorption. The absorbed Cd was directly transported to internode 1 via the xylem and then re-transported to grains via the phloem by up-regulated YSL, ZIP5, and copper transporters (COPT4). This promotion increased the grain Cd content by 245.35%, which was higher than the increased grain dry weight by 132.89%, leading to increased grain Cd concentration in YM51. Our findings concluded that the addition of NH4+-N fertilizer at the seedling stage is not suitable for reducing grain Cd concentration in common wheat cultivars.


Assuntos
Compostos de Amônio , Proteínas de Transporte de Cátions , Poluentes do Solo , Cádmio/análise , Grão Comestível/química , Retículo Endoplasmático/metabolismo , Nitrogênio , Plântula/metabolismo , Poluentes do Solo/análise , Triticum/metabolismo , Zinco/análise
20.
Sci Total Environ ; 791: 148173, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118666

RESUMO

The coordinated supply and demand of ecosystem services (ESs) is important for ensuring regional sustainable development. However, research identifying key areas of imbalanced supply and demand of ESs at the urban agglomeration scale is limited. Therefore, in this study, using the Fujian Delta urban agglomeration of China as the research area, based on multi-source data, and analysis tools, such as ArcGIS, ENVI, and GeoDa, we constructed a research framework and indicator system for ESs supply and demand to determine the spatial change law, matching degree, and coupling coordination degree (CCD) of the ESs. On this basis, the key areas of imbalanced supply and demand of ESs were identified, and optimization strategies were proposed. The results showed that (1) there is obvious spatial heterogeneity between ESs supply and demand in the study area, and different degrees of spatial changes occurred with urbanization. Specifically, areas with large changes were concentrated in urban core areas and economic development zones. (2) The matching degree between ESs supply and demand is quite diverse and shows a trend of polarization. Under the influence of urbanization, some cities began facing ESs supply shortages. (3) Overall, the CCD between ESs supply and demand in the study area is in a state of mild incoordination, but with increasing urbanization, some cities have turned into a state of extreme incoordination. Our results indicate that the ESs supply and demand status in some cities at the urban agglomeration scale has become increasingly severe. Therefore, it is necessary to focus on certain "key areas" to formulate optimization strategies. For key areas with "low supply-high demand" and extreme incoordination, the population and land use intensity should be controlled to reduce the ESs demand level. Meanwhile, for key areas with "high supply-low demand" and extreme incoordination, the utilization efficiency of ecological resources should be improved to enhance the ESs supply capacity. The results of this study will help decision-makers optimize the relationship between ESs supply and demand in order to achieve the sustainable development of urban agglomeration.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Cidades , Urbanização
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