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1.
BMC Plant Biol ; 19(1): 308, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31299895

RESUMO

BACKGROUND: Land preparation is an important component of fragrant rice production. However, the effect of tillage on fragrant rice production is unclear, especially regarding the biosynthesis of 2-acetyl-1-pyrroline (2-AP), which is the main compound of the unique aroma of fragrant rice. This study aimed to explore 2-AP biosynthesis in fragrant rice under different tillage regimes. Three tillage methods were applied in the present study: conventional rotary tillage (CK) as the control, plough tillage (PT), and no-tillage (NT). RESULT: Compared with CK, the PT treatment increased 2-AP content in grain, upregulated the activity of ornithine aminotransferase (OAT) and increased contents of 1-pyrroline and pyrroline-5-carboxylic acid (P5C). Furthermore, the PT treatment increased the grain yield and nitrogen accumulation of fragrant rice. Meanwhile, the 2-AP content in the grain produced under the NT treatment was significantly higher than that in the grain produced under both the PT and CK treatments due to the enhancement of proline content and the activities of proline dehydrogenase (PDH) and △1-pyrroline-5-carboxylic acid synthetase (P5CS). However, the present study observed that the overall production of fragrant rice under NT conditions was inferior due to lower yield, nitrogen accumulation, and anti-oxidative enzymatic activities. Moreover, the organic matter content and soil microorganism quantity increased due to PT and NT treatments. CONCLUSIONS: Compared to CK, PT improved fragrant rice grain yield and nitrogen accumulation and induced an increase in OAT activity and led to an increase in 2-AP concentration. No-tillage also produced increased 2-AP content in grain by enhancing PDH and P5CS activities but limited yields and nitrogen accumulation in fragrant rice.


Assuntos
Oryza/fisiologia , Prolina Oxidase/metabolismo , Pirróis/metabolismo , Odorantes , Oryza/enzimologia , Oryza/genética , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Prolina/análise , Prolina Oxidase/genética , Sementes/enzimologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/fisiologia
2.
J Hum Genet ; 64(8): 815-820, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31164702

RESUMO

Genghis Khan's lineage has attracted both academic and general interest because of its mystery and large influence. However, the truth behind the mystery is complicated and continues to confound the scientific study. In this study, we surveyed the molecular genealogy of Northwestern China's Lu clan who claim to be the descendants of the sixth son of Genghis Khan, Toghan. We also investigated living members of the Huo and Tuo clans, who, according to oral tradition, were close male relatives of Lu clan. Using network analysis, we found that the Y-chromosomal haplotypes of Lu clan mainly belong to haplogroup C2b1a1b1-F1756, widely prevalent in Altaic-speaking populations, and are closely related to the Tore clan from Kazakhstan, who claim to be the descendants of the first son of Genghis Khan, Jochi. The most recent common ancestor of the special haplotype cluster that includes the Lu clan and Tore clan lived about 1000 years ago (YA), while the Huo and Tuo clans do not share any Y lineages with the Lu clan. In addition to the reported lineages, such as C3*-Star Cluster, R1b-M343, and Q, our results indicate that haplogroup C2b1a1b1-F1756 might be another candidate of the true Y lineage of Genghis Khan.

3.
Ann Hum Biol ; : 1-6, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31208219

RESUMO

Background: Previous studies have suggested that the human Y-chromosome haplogroup Q1a1a-M120, a widespread paternal lineage in East Asian populations, originated in South Siberia. However, much uncertainty remains regarding the origin, diversification, and expansion of this paternal lineage. Aim: To explore the origin and diffusion of paternal Q-M120 lineages in East Asia. Subjects and methods: The authors generated 26 new Y chromosome sequences of Q-M120 males and co-analysed 45 Y chromosome sequences of this haplogroup. A highly-revised phylogenetic tree of haplogroup Q-M120 with age estimates was reconstructed. Additionally, a comprehensive phylogeographic analysis of this lineage was performed including 15,007 samples from 440 populations in eastern Eurasia. Results: An ancient connection of this lineage with populations in Siberia was revealed. However, this paternal lineage experienced an in-situ expansion between 5000 and 3000 years ago in northwestern China. Ancient populations with high frequencies of Q-M120 were involved in the formation of ancient Huaxia populations before 2000 years ago; this haplogroup eventually became one of the founding paternal lineages of modern Han populations. Conclusion: This study provides a clear pattern of the origin and diffusion process of haplogroup Q1a1a-M120, as well as the role of this paternal lineage during the formation of ancient Huaxia populations and modern Han populations.

4.
PLoS Genet ; 14(9): e1007664, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30222779

RESUMO

CHIP (carboxyl terminus of heat shock 70-interacting protein) has long been recognized as an active member of the cellular protein quality control system given the ability of CHIP to function as both a co-chaperone and ubiquitin ligase. We discovered a genetic disease, now known as spinocerebellar autosomal recessive 16 (SCAR16), resulting from a coding mutation that caused a loss of CHIP ubiquitin ligase function. The initial mutation describing SCAR16 was a missense mutation in the ubiquitin ligase domain of CHIP (p.T246M). Using multiple biophysical and cellular approaches, we demonstrated that T246M mutation results in structural disorganization and misfolding of the CHIP U-box domain, promoting oligomerization, and increased proteasome-dependent turnover. CHIP-T246M has no ligase activity, but maintains interactions with chaperones and chaperone-related functions. To establish preclinical models of SCAR16, we engineered T246M at the endogenous locus in both mice and rats. Animals homozygous for T246M had both cognitive and motor cerebellar dysfunction distinct from those observed in the CHIP null animal model, as well as deficits in learning and memory, reflective of the cognitive deficits reported in SCAR16 patients. We conclude that the T246M mutation is not equivalent to the total loss of CHIP, supporting the concept that disease-causing CHIP mutations have different biophysical and functional repercussions on CHIP function that may directly correlate to the spectrum of clinical phenotypes observed in SCAR16 patients. Our findings both further expand our basic understanding of CHIP biology and provide meaningful mechanistic insight underlying the molecular drivers of SCAR16 disease pathology, which may be used to inform the development of novel therapeutics for this devastating disease.

5.
Onco Targets Ther ; 11: 3323-3333, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29922071

RESUMO

Introduction: Minichromosome maintenance 10 (MCM10) is deregulated in several malignancies including cervical cancer and urothelial carcinoma. However, the expression and biologic role of MCM10 in esophageal squamous cell carcinoma (ESCC) is still unknown. Methods: In this study, we performed immunohistochemistry and real-time polymerase chain reaction (PCR) analysis to examine the expression of MCM10 in ESCC and adjacent normal esophageal tissues. The associations of MCM10 expression with clinicopathologic parameters of ESCC were analyzed. Ablation of MCM10 through the CRISPR/Cas9 technology was conducted and its impact on ESCC cell growth and migration was investigated. Results: The mRNA and protein expression levels of MCM10 were significantly greater in ESCC than in normal tissues (P<0.001). The expression of MCM10 was significantly associated with age at diagnosis (P=0.033), but not with gender, differentiation grade, invasion status, or tumor-node-metastasis (TNM) stage. Knockout of MCM10 significantly suppressed the proliferation, colony formation, and migration capacity of EC109 ESCC cells, compared to control cells harboring wild-type MCM10. Mechanistically, MCM10 depletion markedly reduced the phosphorylation of Akt. Overexpression of constitutively active Akt significantly restored the aggressive phenotype of MCM10-null EC109 cells. Conclusion: In conclusion, these results suggest that MCM10 acts as an oncogene in ESCC through activation of Akt signaling and represents a promising therapeutic target for this malignancy.

6.
Sci Rep ; 8(1): 7057, 2018 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-29728593

RESUMO

With the increasing demand for higher gene carrier performance, a multifunctional vector could immensely simplify gene delivery for disease treatment; nevertheless, the current non- viral vectors lack self-tracking ability. Here, a type of novel, dual-functional cationic carbon dots (CDs), produced through one-step, microwave-assisted pyrolysis of arginine and glucose, have been utilized as both a self-imaging agent and a non-viral gene vector for chondrogenesis from fibroblasts. The cationic CDs could condense the model gene plasmid SOX9 (pSOX9) to form ultra-small (10-30 nm) nanoparticles which possessed several favorable properties, including high solubility, tunable fluorescence, high yield, low cytotoxicity and outstanding biocompatibility. The MTT assay indicated that CDs/pSOX9 nanoparticles had little cytotoxicity against mouse embryonic fibroblasts (MEFs) compared to Lipofectamine2000 and PEI (25 kDa). Importantly, the CDs/pSOX9 nanoparticles with tunable fluorescence not only enabled the intracellular tracking of the nanoparticles, but also could successfully deliver the pSOX9 into MEFs with significantly high efficiency. Furthermore, the CDs/pSOX9 nanoparticles-mediated transfection of MEFs showed obvious chondrogenic differentiation. Altogether, these findings demonstrated that the CDs prepared in this study could serve as a paradigmatic example of the dual-functional reagent for both self-imaging and effective non-viral gene delivery.

7.
Phys Chem Chem Phys ; 20(15): 10132-10141, 2018 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-29589617

RESUMO

The detailed mechanism of the methanol decomposition reaction (MDR) on the Pt3Ni(100) surface is studied based on self-consistent periodic density functional theory calculations. The geometries and energies of methanol and its intermediates involved in MDR are analyzed, and the reaction network is constructed to illustrate the MDR mechanisms. The possible pathways through initial scission of the O-H, C-H, and C-O bonds in methanol are discussed based on the steric effect and electronic structure of the related transition states and the Brønsted-Evans-Polanyi (BEP) relationships. The initial scission of the O-H bond is favorable and bears the lowest energy barrier among the three decomposition modes (initial scission of O-H, C-H, and C-O bonds). Potential energy surface (PES) analysis confirmed that although the initial scission of the O-H bond is more favorable than scission of the C-H bond, the initial scission of the C-H bond can actually occur because of the very low energy barrier for further dehydrogenation of CH2OH via scission of its O-H bond. Thus, the pathway for MDR on the Pt3Ni(100) surface may possibly proceed via two competitive pathways: CH3OH → CH3O → CH2O → CHO → CO and CH3OH → CH2OH → CH2O → CHO → CO. Comparisons between the current results and the MDR on other systems are made and show that Pt3Ni(100) can be a good catalyst for MDR.

8.
Sensors (Basel) ; 18(3)2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-29538300

RESUMO

This paper presents a complete control strategy of the active return-to-center (RTC) control for electric power steering (EPS) systems. We first establish the mathematical model of the EPS system and analyze the source and influence of the self-aligning torque (SAT). Second, based on the feedback signals of steering column torque and steering wheel angle, we give the trigger conditions of a state switch between the steering assist state and the RTC state. In order to avoid the sudden change of the output torque for the driving motor when the state switches frequently between the steering assist state and the RTC state, we design an undisturbed state switching logic algorithm. This state switching logic algorithm ensures that the output value of the RTC controller is set to an initial value and increases in given steps up to a maximum value after entering the RTC state, and the output value of the RTC controller will reduce in given steps down to zero when exiting the RTC state. This therefore ensures smooth switch control between the two states and improves the driver's steering feeling. Third, we design the RTC controller, which depends upon the feedback signals of the steering wheel angle and the angular velocity. In addition, the controller increases the auxiliary control function of the RTC torque based on vehicle speed. The experimental results show that the active RTC control method does not affect the basic assist characteristics, which effectively reduces the residual angle of the steering wheel at low vehicle speed and improves the RTC performance of the vehicle.

9.
Chem Asian J ; 13(6): 701-709, 2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29377619

RESUMO

New methodology for the alkylation of amines is an intriguing issue in both academia and industry. Recently, several groups reported the metal-free B(C6 F5 )3 -catalyzed N-alkylation of amines, but the mechanistic details of these important reactions are unclear. Herein, a computational study was performed to elucidate the mechanism of the N-alkylation of amines with formic acid catalyzed by the Lewis acid B(C6 F5 )3 in the presence of hydrosilane. We found that the reaction started with the activation of formic acid through a novel model. Then, the high electrophilicity of the C center of the formic acid unit and the nucleophilic character of the amine resulted in a C-N coupling reaction. Finally, two sequential silyl-group and H- transfer steps occurred to generate the final product. Upon comparing the reaction barrier and the hydrogenation of indole, our mechanism is more favorable than that proposed by the group of Yu and Fu.

10.
J Nanobiotechnology ; 15(1): 82, 2017 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-29137640

RESUMO

BACKGROUND: The cell source for transplantation therapy is always a prerequisite question to be solved in clinical applications. Neural cells are considered non-regenerable, which highly restrict their application in the treatment for nerve injury. Therefore, neural trans-differentiation based on gene transfection provides a new solution to this issue. Compared to viral strategy, non-viral gene delivery systems are considered as a more promising way to achieve this aim. This study centers on a novel application of Porphyra yezoensis polysaccharide as a non-viral gene carrier for the neural trans-differentiation of mouse fibroblasts. RESULTS: Ethanediamine modified P. yezoensis polysaccharide (Ed-PYP) served as a gene carrier and a group of plasmids that encode Ascl1, Brn4, and Tcf3 (pABT) self-assembled into nanoparticles. Results demonstrated that Ed-PYP-pABT nanoparticles at Ed-PYP: pABT weight ratio of 40:1 was the optimal candidate for gene delivery. ELISA assay revealed the highest expression levels of NGF, BDNF and SHH at 14 days after last transfection. Immunofluorescence and western blot assays also showed robust expression of neural markers including Nestin, GFAP, ß-3tubulin, NF200, GAP43 and MAP2, in induced 3T6 cells at this time point. CONCLUSION: Overall, these findings indicated that the P. yezoensis polysaccharide-based non-viral gene co-delivery system is a promising strategy for the generation of neural cells, which might facilitate the developments in the recovery of neural injuries.


Assuntos
Fibroblastos/efeitos dos fármacos , Técnicas de Transferência de Genes , Nanopartículas , Neurônios/efeitos dos fármacos , Polissacarídeos/farmacologia , Porphyra/química , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Biomarcadores/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Transdiferenciação Celular/efeitos dos fármacos , Reprogramação Celular/efeitos dos fármacos , Etilenodiaminas/química , Fibroblastos/citologia , Fibroblastos/metabolismo , Expressão Gênica , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Camundongos , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Fatores do Domínio POU/genética , Fatores do Domínio POU/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Polissacarídeos/química , Polissacarídeos/isolamento & purificação
11.
Rev Med Suisse ; 13(555): 660-663, 2017 Mar 22.
Artigo em Francês | MEDLINE | ID: mdl-28721709

RESUMO

Natriuretic peptides (NP), ANP and BNP, are produced by cardiomyocytes when there is stretching of the ventricular and auricular walls in heart failure (HF). Their vasodilatator and natriuretic effect oppose to volume and pressure overload occurring in HF. Several studies have observed decreased levels of NP in obese and diabetic people and in patients with insulin resistance. This decrease could contribute to hypertension, frequently observed in obesity. NP have also a lipolytic action. Low levels of NP could promote obesity. Therefore in obese patients normal BNP levels cannot a priori exclude HF. Normal values must be adjusted according to obesity degree and heart failure stage.


Assuntos
Hipertensão/etiologia , Peptídeo Natriurético Encefálico/metabolismo , Obesidade/metabolismo , Diabetes Mellitus/metabolismo , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipertensão/epidemiologia , Resistência à Insulina , Obesidade/fisiopatologia
12.
Theranostics ; 7(8): 2250-2260, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28740548

RESUMO

The weakened tumour colonization of attenuated Salmonella has severely hampered its clinical development. In this study, we investigated whether an anti-inflammation and antiangiogenesis compound triptolide could improve the efficacy of VNP20009, a highly attenuated Salmonella strain, against mice melanoma. By comparing the effects of conventional VNP20009 monotherapy and a combination therapy that uses both triptolide and VNP20009, we found that triptolide significantly improved the tumour colonization of VNP20009 by reducing the number of infiltrated neutrophils in the melanoma, which led to a larger necrotic area in the melanoma. Moreover, the combination therapy suppressed tumour angiogenesis by reducing the expression of VEGF in a synergistic manner, retarding the growth of the melanoma. Our study revealed that triptolide could significantly enhance the antitumour effect of VNP20009 by modulating tumour angiogenesis and the host immune response, providing a new understanding of the strategy to improve Salmonella-mediated tumour therapy.


Assuntos
Diterpenos/metabolismo , Diterpenos/farmacologia , Imunossupressores/metabolismo , Imunossupressores/farmacologia , Melanoma/terapia , Fenantrenos/metabolismo , Fenantrenos/farmacologia , Salmonella/efeitos dos fármacos , Salmonella/crescimento & desenvolvimento , Animais , Terapia Biológica/métodos , Terapia Combinada/métodos , Modelos Animais de Doenças , Compostos de Epóxi/metabolismo , Compostos de Epóxi/farmacologia , Melanoma/microbiologia , Melanoma/patologia , Camundongos Endogâmicos C57BL , Necrose , Neovascularização Patológica/tratamento farmacológico , Neutrófilos/imunologia , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
13.
J Hum Genet ; 62(10): 915-918, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28566770

RESUMO

In previous studies, a specific paternal lineage with a null value for the Y-chromosome short tandem repeat (Y-STR) marker DYS448 was identified as common among Mongolic- and Turkic-speaking populations. This paternal lineage (temporarily named C3*-DYS448del) was determined to be M217+, M93-, P39-, M48-, M407-, and P53.1-, and its origin and phylogeny remain ambiguous. Here, we analyzed Y-chromosome sequences of 10 male that are related this paternal lineage and redefined it as C3b1a1a1a-F1756 (C3b-F1756). We generated a highly revised phylogenetic tree of haplogroup C3b-F1756, including 21 sub-clades and 360 non-private Y-chromosome polymorphisms. Additionally, we performed a comprehensive analysis of the C3*-DYS448del lineage in eastern Eurasia, including 18 270 samples from 297 populations. Whole Y-chromosome sequences, Y-STR haplotypes, and frequency data were used to generate a distribution map, a network, and age estimations for lineage C3*-DYS448del and its sub-lineages. Considering the historical records of the studied populations, we propose that two major sub-branches of C3b-F1756 may correspond to early expansions of ancestors of modern Mongolic- and Turkic-speaking populations. The large number of newly defined Y-chromosome polymorphisms and the revised phylogenetic tree for C3b-F1756 will assist in investigation of the early history of Altaic-speaking populations in the future.


Assuntos
Cromossomos Humanos Y , Grupos Étnicos/genética , Haplótipos , Repetições de Microssatélites , Herança Paterna , Filogenia , Locos de Características Quantitativas , Evolução Molecular , Marcadores Genéticos , Humanos , Masculino , Mongólia , Polimorfismo de Nucleotídeo Único , Turquia
14.
Int J Mol Sci ; 18(6)2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28587243

RESUMO

Human pancreatic cancer has a very poor prognosis with an overall five-year survival rate of less than 5% and an average median survival time of six months. This is largely due to metastatic disease, which is already present in the majority of patients when diagnosed. Although our understanding of the molecular events underlying multi-step carcinogenesis in pancreatic cancer has steadily increased, translation into more effective therapeutic approaches has been inefficient in recent decades. Therefore, it is imperative that novel and targeted approaches are designed to facilitate the early detection and treatment of pancreatic cancer. Presently, there are numerous ongoing studies investigating the types of genomic variations in pancreatic cancer and their impact on tumor initiation and growth, as well as prognosis. This has led to the development of therapeutics to target these genetic variations for clinical benefit. Thus far, there have been minimal clinical successes directly targeting these genomic alterations; however research is ongoing to ultimately discover an innovative approach to tackle this devastating disease. This review will discuss the genomic variations in pancreatic cancer, and the resulting potential diagnostic and therapeutic implications.


Assuntos
Variação Genética , Genômica , Neoplasias Pancreáticas/genética , Animais , Biomarcadores Tumorais , Transformação Celular Neoplásica/genética , Gerenciamento Clínico , Testes Genéticos , Instabilidade Genômica , Genômica/métodos , Humanos , Imunidade/genética , Mutação , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/terapia , Prognóstico , Resultado do Tratamento
15.
Biochimie ; 138: 13-19, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28408247

RESUMO

Parathyroid hormone-related protein (PTHrP), a ubiquitously expressed protein, is composed of four functional domains including N-terminus, mid region, nuclear localization signal (NLS) and C-terminus. Under the direction of NLS, PTHrP can enter cell nucleus from cytoplasm and stimulate mitogenesis. Although PTHrP is considered to have important developmental roles, the role of PTHrP NLS and C-terminus in developmental process remains unknown, especially in T-cell development. Here, we used a knock-in mouse model, which expresses a truncated form of PTHrP missing the NLS (87-107) and C-terminus (108-139) of the protein, to examine the role of PTHrP NLS and C-terminus in T-cell development. Our results showed that the truncated PTHrP (1-84) led to abnormal subpopulations, impaired proliferation and increased apoptosis in the thymus, indicating that PTHrP is involved in the development of T cells, and the NLS and C-terminus part is necessary for the normal role of PTHrP in T-cell development.


Assuntos
Sequência de Aminoácidos , Sinais de Localização Nuclear , Proteína Relacionada ao Hormônio Paratireóideo/genética , Deleção de Sequência , Linfócitos T/metabolismo , Animais , Apoptose , Proliferação de Células , Camundongos , Modelos Animais , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Linfócitos T/fisiologia
16.
Talanta ; 164: 100-109, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28107902

RESUMO

This work reports a facile electrolyzing method to synthesize boron-doped graphene quantum dots (BGQDs) and uses the BGQDs as a fluorescent probe to determine Fe3+ ion levels in water samples. The BGQDs were produced by oxidizing graphite in an aqueous borax solution at pH 7; then, the borate solution was filtered with BGQDs, and the borate was dialyzed from the filtrate, leaving a solution of BGQDs in water. The amount of the B in the BGQDs can be adjusted by changing the concentration of borax used for the electrolyte. The excitation wavelength- and B amount-dependent fluorescence characteristics of BQGDs were studied. The fluorescence intensity of the BGQDs is measurable in real time, and its quenching is very sensitive to the concentration of Fe3+ ions in the system but not to other possible coexisting metal ions. The fluorescence quenching mechanism of Fe3+ ions to BGQDs is studied and explained based on electrochemical voltammetry and DFT simulations. The analytical signal, which is defined as F0/F, where F0 and F are the fluorescence intensities of the BGQDs before and after interaction with Fe3+ ions, respectively, displays a good linear relationship in the Fe3+ ion concentration range of 0.01-100µm with a correlation coefficient of 0.999 and a limit of detection (LOD) of ~(0.005±0.001) µM. The LOD value is much lower than the water quality standards for Fe3+ ions (0.3ppm, ~5.36µm) in drinking water suggested by the WHO (World Health Organization) and EPA (U.S. Environmental Protection Agency), implying that this method has great potential for applications in real sample assays. For example, the determination of the Fe3+ ion levels in three water samples (tap water, groundwater, and lake water) gives approximately the same results as those determined by the EPA-recommended AAS (atomic adsorption spectroscopy) method.

17.
Ying Yong Sheng Tai Xue Bao ; 28(1): 142-150, 2017 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29749198

RESUMO

In the winter-wheat and summer-maize multiple cropping system in lime concretion black soil of Huanghuaihai Plain, the effects of three tilling methods (conventional tillage, rotary tillage, subsoiling tillage) in wheat season coupling with three nitrogen treatments (120 kg·hm-2, 225 kg·hm-2, 330 kg·hm-2) before maize sowing on the activities of microorganisms and enzymes re-lated nitrogen transformation, and inorganic nitrogen content in the rhizosphere soil during the main growth stages of maize, as well as the yield were investigated. The results showed that the rotary tillage had the highest ammonification intensity, and the more nitrogen was put in, the higher were the activities of microorganisms and enzymes related to soil nitrogen transformation. The activities of nitrification, denitrification and urease of subsoiling tillage was significantly higher than those of conventional and rotary tillage. Furthermore, in subsoiling tillage treatment, increasing nitrogen fertili-zer could promote soil nitrogen transformation while excessive nitrogen input inhibited soil nitrogen transformation, though the latter had higher yield and soil inorganic nitrogen content. The treatment of subsoiling tillage coupling with 225 kg·hm-2 nitrogen, was best for soil nitrogen transformation while the treatment of subsoiling tillage coupling with 330 kg·hm-2 nitrogen, had the highest corn yield.


Assuntos
Nitrogênio , Triticum , Zea mays , Agricultura , Solo
18.
Parkinsonism Relat Disord ; 34: 59-61, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27814975

RESUMO

INTRODUCTION: A founder mutation, p.L302P, in sphingomyelin phosphodiesterase 1, acid lysosomal (SMPD1), causing Niemann-Pick disease, a recessive lysosomal storage disorder, was reported to be associated with increased risk of Parkinson's disease (PD) in Ashkenazi Jewish population. Several other studies about the association between SMPD1 variants and PD were performed afterward in other populations. However, the results on the role of SMPD1 mutations for PD have been conflicting. This study aimed to investigate the role of mutations in SMPD1 in Chinese PD patients. METHODS: We sequenced all the exons of this gene in 512 Chinese Han cases with sporadic Parkinson's disease and 495 matched healthy control subjects. RESULTS: We identified Leu-Ala (Val) repeat variants and six known single nucleotide variants (p.A36V, p.D212D, p.P332R, p.G508R, p.P533L, p.T544T) in SMPD1 in both patients and normal controls. Case-control analysis showed the association between Leu-Ala (Val) repeat variants in SMPD1and Chinese Han patients with PD (χ2 = 8.771, p = 0.012), and the allele with less than seven LeuAla (Val) repeats may increase the risk of PD (p = 0.010). CONCLUSION: We identified association between Leu-Ala (Val) repeat variants in SMPD1 and Chinese Han patients with sporadic Parkinson's disease. Our results provide further support for the role of lysosomal pathways in PD development.


Assuntos
Estudos de Associação Genética , Variação Genética/genética , Doença de Parkinson/genética , Esfingomielina Fosfodiesterase/genética , Idoso , Grupo com Ancestrais do Continente Asiático/etnologia , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , Dipeptídeos/genética , Éxons/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Biochem Biophys Res Commun ; 478(4): 1726-31, 2016 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-27601324

RESUMO

Previous studies have demonstrated a significantly lower level of Hand1 in ischemic cardiomyopathy than in normal heart tissue. The role of decreased Hand1 in myocardial infarction remains unclear. This study was designed to investigate the effects of haploinsufficiency of Hand1 on mouse heart after myocardial infarction. 8-10 weeks old male heterozygous Hand1-deficient (Hand1(+/-)) mice and wild-type littermates (control) were subjected to sham operation or ligation of the left anterior descending coronary artery to induce acute myocardial infarction (AMI). Hand1(+/-) mice have low incidence of left ventricular free wall rupture in the first week after operation than control mice. Then we found lower MMP9 activity and less cardiomyocytes apoptosis in Hand1(+/-) than in control mice. All of these contribute to the protection role of haploinsufficiency of Hand1 after AMI.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Haploinsuficiência , Ruptura Cardíaca/genética , Infarto do Miocárdio/genética , Animais , Apoptose/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Western Blotting , Ecocardiografia , Coração/fisiopatologia , Ruptura Cardíaca/metabolismo , Ruptura Cardíaca/mortalidade , Heterozigoto , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia de Fluorescência , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/mortalidade , Miocárdio/metabolismo , Miocárdio/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida , Taxa de Sobrevida
20.
ACS Appl Mater Interfaces ; 8(31): 19916-27, 2016 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-27428246

RESUMO

Reprogramming somatic cells into a pluripotent state has been widely investigated in two-dimensional (2D) systems but not described in the more biologically faithful three-dimensional (3D) scaffolds. Here, we devise a 3D porous tissue engineering scaffold that could achieve successful and efficient induction of pluripotency. To construct this 3D scaffold, nonviral hybrid nanoparticles were fabricated beforehand by employing calcium phosphate and cationized Pleurotus eryngii polysaccharide to codeliver plasmids OCT4, SOX2, KLF4 ,and C-MYC (pOSKM). These hybrid nanoparticles were then loaded into a 3D porous collagen scaffold to obtain the so-called pOSKM-activated 3D scaffold. This 3D scaffold could reprogram human umbilical cord mesenchymal stem cells (HUMSCs) into a pluripotent state, generating 3D cell spheres which showed positive expression of pluripotency markers in the 3D scaffolds and tightly packed colonies when transferred to 2D feeder layers. Besides sharing similar morphology, epigenetic modification, and expression of pluripotency genes with the embryonic stem cells, the 3D system-generated colonies could also be expanded on feeder layers for more than 20 passages, indicating the successful establishment of stable induced pluripotent stem cell (iPSC) lines. Our findings represent a first employment of porous 3D scaffolds to achieve successful reprogramming via a one-time transfection, offering a safe, simple, and effective alternative strategy for iPSC generation.


Assuntos
Reprogramação Celular , Diferenciação Celular , Células-Tronco Embrionárias , Humanos , Células-Tronco Pluripotentes Induzidas , Transfecção
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