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1.
Cell Mol Biol Lett ; 29(1): 123, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39277732

RESUMO

BACKGROUND: Loss-of-function mutations of ZBTB24 cause immunodeficiency, centromeric instability, and facial anomalies syndrome 2 (ICF2). ICF2 is a rare autosomal recessive disorder with immunological defects in serum antibodies and circulating memory B cells, resulting in recurrent and sometimes fatal respiratory and gastrointestinal infections. The genotype-phenotype correlation in patients with ICF2 indicates an essential role of ZBTB24 in the terminal differentiation of B cells. METHODS: We used the clustered regularly interspaced short palindromic repeats (CRISPER)/Cas9 technology to generate B cell specific Zbtb24-deficient mice and verified the deletion specificity and efficiency by quantitative polymerase chain reaction (Q-PCR) and western blotting analyses in fluorescence-activated cell sorting (FACS)-sorted cells. The development, phenotype of B cells and in vivo responses to T cell dependent or independent antigens post immunization were analyzed by flow cytometry and enzyme-linked immunosorbent assay (ELISA). Adoptive transfer experiment in combination with in vitro cultures of FACS-purified B cells and RNA-Seq analysis were utilized to specifically determine the impact of Zbtb24 on B cell biology as well as the underlying mechanisms. RESULTS: Zbtb24 is dispensable for B cell development and maintenance in naive mice. Surprisingly, B cell specific deletion of Zbtb24 does not evidently compromise germinal center reactions and the resulting primary and secondary antibody responses induced by T cell dependent antigens (TD-Ags), but significantly inhibits T cell independent antigen-elicited antibody productions in vivo. At the cellular level, Zbtb24-deficiency specifically impedes the plasma cell differentiation of B1 cells without impairing their survival, activation and proliferation in vitro. Mechanistically, Zbtb24-ablation attenuates heme biosynthesis partially through mTORC1 in B1 cells, and addition of exogenous hemin abrogates the differentiation defects of Zbtb24-null B1 cells. CONCLUSIONS: Zbtb24 seems to regulate antibody responses against TD-Ags B cell extrinsically, but it specifically promotes the plasma cell differentiation of B1 cells via heme synthesis in mice. Our study also suggests that defected B1 functions contribute to recurrent infections in patients with ICF2.


Assuntos
Diferenciação Celular , Doenças da Imunodeficiência Primária , Fatores de Transcrição , Animais , Camundongos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Face/anormalidades , Síndromes de Imunodeficiência/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doenças da Imunodeficiência Primária/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo
2.
Environ Sci Technol ; 56(16): 11835-11844, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35905396

RESUMO

Mercury (Hg) is a ubiquitous contaminant in the environment and its methylated form, methylmercury (MeHg), poses a worldwide health concern for humans and wildlife, primarily through fish consumption. Global production of forest fire ash, derived from wildfires and prescribed burns, is rapidly increasing due to a warming climate, but their interactions with aqueous and sedimentary Hg are poorly understood. Herein, we compared the differences of wildfire ash with activated carbon and biochar on the sorption of aqueous inorganic Hg and sedimentary Hg methylation. Sorption of aqueous inorganic Hg was greatest for wildfire ash materials (up to 0.21 µg g-1 or 2.2 µg g-1 C) among all of the solid sorbents evaluated. A similar Hg adsorption mechanism for activated carbon, biochar made of walnut, and wildfire ash was found that involves the formation of complexes between Hg and oxygen-containing functional groups, especially the -COO group. Notably, increasing dissolved organic matter from 2.4 to 70 mg C L-1 remarkably reduced Hg sorption (up to 40% reduction) and increased the time required to reach Hg-sorbent pseudo-equilibrium. Surprisingly, biochar and wildfire ash, but not activated carbon, stimulated MeHg production during anoxic sediment incubation, possibly due to the release of labile organic matter. Overall, our study indicates that while wildfire ash can sequester aqueous Hg, the leaching of its labile organic matter may promote production of toxic MeHg in anoxic sediments, which has an important implication for potential MeHg contamination in downstream aquatic ecosystems after wildfires.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Incêndios Florestais , Animais , Ecossistema , Sedimentos Geológicos , Humanos , Mercúrio/análise , Poluentes Químicos da Água/análise
3.
Environ Geochem Health ; 44(3): 1161-1173, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34195906

RESUMO

This is the first investigation that identified seasonal variation, possible sources and health risk of 16 PAHs in street dust sampled park area (PA), educational area (EA), commercial area (CA), residential area (RA), and traffic area (TA) of Chengdu, one of the new first-tier cities in China. The total PAHs (∑16PAHs) concentrations of averaging over two seasons varied from 2.15 to 10.6 mg/kg with a median value of 4.61 mg/kg and in winter (5.48 ± 1.52 mg/kg) were significantly higher than that in summer (4.04 ± 0.91 mg/kg). The highest ∑16PAHs concentration was found in TA (median 6.74 mg/kg). Statistical analysis results indicated that mixture sources of petroleum combustion and combustion of biomass and coal seem to be the primary source of the PAHs in street dust. Carcinogenic risk by incremental lifetime cancer risk (ILCR) model for PAHs in street dust indicates an acceptable potential cancer risk for residents. The same sequences of cancer risk to be observed for both children and adults among different functional areas: TA > CA > EA > RA > PA. The results provided advice for habitants in Chengdu to encourage outdoor activities in parks and residential areas and minimize traffic areas and commercial areas.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Adulto , Poluentes Atmosféricos/análise , Criança , China/epidemiologia , Cidades , Poeira/análise , Monitoramento Ambiental/métodos , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Estações do Ano
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(3): 952-7, 2017 Mar.
Artigo em Zh, Inglês | MEDLINE | ID: mdl-30160448

RESUMO

As one of the most important ways of improving the calibration accuracy at present, the calibration method based on a solar diffuser(SD) is an independent calibration way with advantages of high accuracy, high frequency and high efficiency . The principles, methods and implementation process of on-orbit calibration based on the SD is described in this thesis. The radiance reference for calibration in space is found and the physical model of the on-orbit reflectance calibration is provided. The main factor which affects the calibration uncertainty is the determination of the SD bidirectional reflectance distribution function (BRDF) value by analyzing the physical models of on-orbit calibration. Thus, the timing selection of the on-orbit calibration is introduced and the BRDF in the range of angles variety within the calibration timing is tested in the lab. During the on-orbit calibration time, the high accuracy on-orbit calibration in the remote sensors' whole life is achieved by the accurate radiance input which is ensured by monitoring and correcting the SD BRDF value from its fabrication to its life end. Finally, the on-orbit calibration uncertainty is estimated based on the measurement levels of the parameters in the physical model. And the uncertainties of on-orbit reflectance calibration and method of radiance calibration are better than 2.03% and 2.04% by type B standard uncertainty evaluation method.

5.
Environ Res ; 150: 423-430, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27372065

RESUMO

Phthalate esters are used in a wide variety of consumer products, and human exposure to this class of compounds is widespread. Nevertheless, studies on dietary exposure of human to phthalates are limited. In this study, to assess the daily intakes of phthalate esters and the possible adverse health impacts, different food samples were collected from three areas of Cambodia, one of the poorest countries in the world. The ∑phthalate ester concentrations in Kampong Cham, Kratie and Kandal provinces ranged from 0.05 to 2.34 (median 0.88) µgg(-1), 0.19-1.65 (median 0.86) µgg(-1) and 0.24-3.05 (median 0.59) µgg(-1) wet weight (ww), respectively. Di-2-Ethylhexyl phthalate (DEHP) and diisobutyl phthalate (DiBP) were the predominant compounds among all foodstuffs. The estimated daily intake (EDI) of phthalate esters for the general population in Kampong Cham, Kratie and Kandal was 34.3, 35.6 and 35.8µgkg(-1) bw d(-1), respectively. The dietary daily intake of DEHP, benzylbutyl phthalate (BBP) and di-n-butyl phthalate (DBP) in Kampong Cham, Kratie and Kandal were below the tolerable daily intakes (TDI) imposed by the European Food Safety Authority (EFSA) and reference doses (RfD) imposed by The United States Environmental Protection Agency (USEPA). Rice contributed the greatest quantity of DEHP to the daily intake in Cambodia so may deserve further exploration. To our knowledge, this is the first study to investigate the occurrence and the daily intakes of phthalate esters in Cambodia.


Assuntos
Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Oryza/química , Ácidos Ftálicos/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Camboja , Criança , Dieta , Monitoramento Ambiental , Ésteres , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Inquéritos e Questionários , Adulto Jovem
6.
Zhongguo Dang Dai Er Ke Za Zhi ; 18(6): 492-5, 2016 Jun.
Artigo em Zh | MEDLINE | ID: mdl-27324535

RESUMO

OBJECTIVE: To investigate the association between two single nucleotide polymorphisms (SNPs), rs9390754 and rs4840200, in the glutamate receptor 2 (GRIK2) gene and the genetic susceptibility to epilepsy (EP) in the Han population in Central China. METHODS: A case-control study was performed in 284 EP children (including 132 children with refractory epilepsy) and 315 normal children from Central China. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to determine the genotypes of the two SNPs rs9390754 and rs4840200. The genotype frequency was compared between groups. RESULTS: The frequencies of GG, GA, and AA genotypes of SNP rs9390754 showed a significant difference between the EP and normal control groups (P=0.016). The allele frequency also showed a significant difference between the two groups (P=0.002). The frequencies of CC, CT, and TT genotypes of SNP rs4840200 and allele frequency showed no significant differences between the two groups. The C allele frequency of SNP rs4840200 in the refractory EP subgroup was significantly higher than in the non-refractory EP subgroup (OR=1.435, 95% CI: 1.021-2.016, P=0.037). CONCLUSIONS: In the Han population in Central China, the polymorphisms of SNP rs9390754 in the GRIK2 gene may be associated with EP susceptibility, and the C allele of SNP rs4840200 may be a genetic risk factor for the development of drug resistance in children with EP.


Assuntos
Epilepsia/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Receptores de Ácido Caínico/genética , Criança , Pré-Escolar , Epilepsia/etiologia , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Fatores de Risco , Receptor de GluK2 Cainato
7.
Food Res Int ; 186: 114317, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729709

RESUMO

Lipids play a pivotal role in the nutrition of preterm infants, acting as a primary energy source. Due to their underdeveloped gastrointestinal systems, lipid malabsorption is common, leading to insufficient energy intake and slowed growth. Therefore, it is critical to explore the reasons behind the low lipid absorption rate in formulas for preterm infants. This study utilized a simulated in intro gastrointestinal digestion model to assess the differences in lipid digestion between preterm human milk and various infant formulas. Results showed that the fatty acid release rates for formulas IF3, IF5, and IF7 were 58.90 %, 56.58 %, and 66.71 %, respectively, lower than human milk's 72.31 %. The primary free fatty acids (FFA) and 2-monoacylglycerol (2-MAG) released during digestion were C14:0, C16:0, C18:0, C18:1n-9, and C18:2n-6, in both human milk and formulas. Notably, the higher release of C16:0 in formulas may disrupt fatty acid balance, impacting lipid absorption. Further investigations are necessary to elucidate lipid absorption differences, which will inform the optimization of lipid content in preterm infant formulas.


Assuntos
Digestão , Fórmulas Infantis , Recém-Nascido Prematuro , Leite Humano , Leite Humano/química , Leite Humano/metabolismo , Humanos , Fórmulas Infantis/química , Recém-Nascido , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Lipídeos/análise , Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/metabolismo , Metabolismo dos Lipídeos , Trato Gastrointestinal/metabolismo , Modelos Biológicos , Monoglicerídeos/metabolismo , Monoglicerídeos/análise , Gorduras na Dieta/metabolismo , Gorduras na Dieta/análise
8.
J Food Sci ; 89(7): 4109-4122, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38957103

RESUMO

The elucidation of the interaction mechanism between phospholipids and milk proteins within emulsions is pivotal for comprehending the properties of infant formula fat globules. In this study, multispectral methods and molecular docking were employed to explore the relationship between phosphatidylcholine (PC) and whey protein isolate (WPI). Observations indicate that the binding constant, alongside thermodynamic parameters, diminishes as temperature ascends, hinting at a predominantly static quenching mechanism. Predominantly, van der Waals forces and hydrogen bonds constitute the core interactions between WPI and PC. This assertion is further substantiated by Fourier transform infrared spectroscopy, which verifies PC's influence on WPI's secondary structure. A detailed assessment of thermodynamic parameters coupled with molecular docking reveals that PC predominantly adheres to specific sites within α-lactalbumin, ß-lactoglobulin, and bovine serum albumin, propelled by a synergy of hydrophobic interactions, hydrogen bonding, and van der Waals forces, with binding energies noted at -5.59, -6.71, and -7.85 kcal/mol, respectively. An increment in PC concentration is observed to amplify the emulsification properties of WPI whilst concurrently diminishing the zeta potential. This study establishes a theoretical foundation for applying the PC-WPI interaction mechanism in food.


Assuntos
Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Simulação de Acoplamento Molecular , Fosfatidilcolinas , Termodinâmica , Proteínas do Soro do Leite , Proteínas do Soro do Leite/química , Fosfatidilcolinas/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Emulsões/química , Lactalbumina/química , Lactalbumina/metabolismo , Soroalbumina Bovina/química , Fórmulas Infantis/química
9.
Int J Ophthalmol ; 17(6): 1128-1137, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895669

RESUMO

AIM: To figure out whether various atropine dosages may slow the progression of myopia in Chinese kids and teenagers and to determine the optimal atropine concentration for effectively slowing the progression of myopia. METHODS: A systematic search was conducted across the Cochrane Library, PubMed, Web of Science, EMBASE, CNKI, CBM, VIP, and Wanfang database, encompassing literature on slowing progression of myopia with varying atropine concentrations from database inception to January 17, 2024. Data extraction and quality assessment were performed, and a network Meta-analysis was executed using Stata version 14.0 Software. Results were visually represented through graphs. RESULTS: Fourteen papers comprising 2475 cases were included; five different concentrations of atropine solution were used. The network Meta-analysis, along with the surface under the cumulative ranking curve (SUCRA), showed that 1% atropine (100%)>0.05% atropine (74.9%) >0.025% atropine (51.6%)>0.02% atropine (47.9%)>0.01% atropine (25.6%)>control in refraction change and 1% atropine (98.7%)>0.05% atropine (70.4%)>0.02% atropine (61.4%)>0.025% atropine (42%)>0.01% atropine (27.4%)>control in axial length (AL) change. CONCLUSION: In Chinese children and teenagers, the five various concentrations of atropine can reduce the progression of myopia. Although the network Meta-analysis showed that 1% atropine is the best one for controlling refraction and AL change, there is a high incidence of adverse effects with the use of 1% atropine. Therefore, we suggest that 0.05% atropine is optimal for Chinese children to slow myopia progression.

10.
Funct Integr Genomics ; 13(2): 241-51, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23474989

RESUMO

Plant annexins are Ca(2+)- and phospholipid-binding proteins forming an evolutionary conserved multi-gene family. They are implicated in the regulation of plant growth, development, and stress responses. With the availability of the maize genome sequence information, we identified 12 members of the maize annexin genes. Analysis of protein sequence and gene structure of maize annexins led to their classification into five different orthologous groups. Expression analysis by RT-PCR revealed that these genes are responsive to heavy metals (Ni, Zn, and Cd). The maize annexin genes were also found to be regulated by Ustilago maydis and jasmonic acid. Additionally, the promoter of the maize annexin gene was analyzed for the presence of different stress-responsive cis-elements, such as ABRE, W-box, GCC-box, and G-box. RT-PCR and microarray data show that all 12 maize annexin genes present differential, organ-specific expression patterns in the maize developmental steps. These results indicate that maize annexin genes may play important roles in the adaptation of plants to various environmental stresses.


Assuntos
Anexinas/genética , Ciclopentanos/farmacologia , Metais Pesados/toxicidade , Oxilipinas/farmacologia , Zea mays/efeitos dos fármacos , Zea mays/genética , Sequência de Aminoácidos , Anexinas/química , Anexinas/metabolismo , Sequência de Bases , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/genética , Dados de Sequência Molecular , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Zea mays/crescimento & desenvolvimento
11.
Funct Integr Genomics ; 13(2): 229-39, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23455933

RESUMO

Nicotianamine (NA) is an important divalent metal chelator and the main precursor of phytosiderophores. NA is synthesized from S-adenosylmethionine in a process catalyzed by nicotianamine synthase (NAS). In this study, a set of structural and phylogenetic analyses have been applied to identify the maize NAS genes based on the maize genome sequence release. Ten maize NAS genes have been mapped; seven of them have not been reported to date. Phylogenetic analysis and expression pattern from microarray data led to their classification into two different orthologous groups. C-terminal fusion of ZmNAS3 with GFP was found in the cytoplasm of Arabidopsis leaf protoplast. Expression analysis by reverse transcription polymerase chain reaction revealed ZmNAS genes are responsive to heavy metal ions (Ni, Fe, Cu, Mn, Zn, and Cd), and all 10 ZmNAS genes were only observed in the root tissue except of ZmNAS6. The promoter of ZmNAS genes was analyzed for the presence of different cis-element response to all kinds of phytohormones and environment stresses. We found that the ZmNAS gene expression of maize seedlings was regulated by jasmonic acid, abscisic acid, and salicylic acid. Microarray data demonstrated that the ZmNAS genes show differential, organ-specific expression patterns in the maize developmental steps. The integrated comparative analysis can improve our current view of ZmNAS genes and facilitate the functional characterization of individual members.


Assuntos
Alquil e Aril Transferases/genética , Genes de Plantas/genética , Metais Pesados/toxicidade , Família Multigênica , Reguladores de Crescimento de Plantas/farmacologia , Zea mays/enzimologia , Zea mays/genética , Biocatálise/efeitos dos fármacos , Citoplasma/efeitos dos fármacos , Citoplasma/enzimologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Modelos Moleculares , Análise de Sequência com Séries de Oligonucleotídeos , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Filogenia , Regiões Promotoras Genéticas/genética , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/genética , S-Adenosilmetionina/química , S-Adenosilmetionina/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Homologia Estrutural de Proteína , Zea mays/efeitos dos fármacos
12.
J Basic Microbiol ; 53(2): 181-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22581711

RESUMO

The rutin degrading enzyme (RDE) was isolated and purified from tartary buckwheat seeds. The RDE was purified about 11.34-fold and its final yield was 3.5%, which was very low, due to our purification strategy of giving priority to purity over yield. The RDE molecular weight was estimated to be about 60 kDa. When rutin was used as substrate, an optimal enzyme activity was seen at around pH 5.0 and 40 °C. Strains isolation strategy characterized by the use of rutin as sole carbon source in enrichment cultures was used to isolate RDE-producing strains. Then the active strains were identified by morphology characterization and 18s rDNA-ITS (Internal Transcribed Spacer) gene sequencing. Three isolates coded as B3, W2, Y2 were successfully isolated from fusty Fagopyrum tataricum flour cultures. Strain B3 possessed the highest unit activity among these three strains, and its total activity reached up to 171.0 Unit. The active isolate (B3) could be assigned to Penicillium farinosum. When the Penicillium farinosum strains were added to tartary buckwheat flour cultures at pH 5.0, 30 °C after 5 days fermentation, the quercetin production raised up to 1.78 mg/l, almost 5.1 times higher than the fermentation without the above active strains. Hence, a new approach was available to utilize microorganism-aided fermentation for effective quercetin extraction from Fagopyrum tataricum seeds.


Assuntos
Enzimas/isolamento & purificação , Enzimas/metabolismo , Fagopyrum/enzimologia , Rutina/metabolismo , Biotransformação , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Enzimas/química , Concentração de Íons de Hidrogênio , Peso Molecular , Penicillium/classificação , Penicillium/genética , Penicillium/isolamento & purificação , Sementes/enzimologia , Análise de Sequência de DNA , Temperatura
13.
Food Res Int ; 167: 112664, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37087249

RESUMO

Protein-based high internal phase Pickering emulsions (HIPPEs) feature numerous multi-functionalities and widespread applications. However, the direct use of native proteins for the constructions of HIPPEs is limited since it is fragile under various conditions. Here, cold plasma was used to modify soy protein isolates (SPI) to improve their surficial properties. Meanwhile, proanthocyanidins (PA) were applied to interact with cold plasma-treated SPI to form complex. Furthermore, the well-prepared SPI-PA complex was used to construct novel HIPPEs. Results showed cold plasma treatment significantly improved the functionalities of SPI, which were confirmed by surface hydrophobicity (H0 < 500), sulfhydryl (SH) groups and spectral analysis. Further, the emulsification and oxidation resistance of cold plasma treated SPI were enhanced after forming complex with PA. Soybean oils can be stabilized by SPI-PA complexes to form HIPPEs with a lipid oxidation inhibition rate of > 65%, creaming index (CI) > 80%, excellent rheological properties and better stability compared with conventional emulsion systems. Overall, this SPI-PA complexes provides a unique approach to improve the emulsification and oxidation resistance to engineer HIPPEs with versatile applications.


Assuntos
Gases em Plasma , Proantocianidinas , Emulsões , Proteínas de Soja/farmacologia , Oxirredução
14.
Glycobiology ; 22(12): 1775-85, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22879458

RESUMO

The raffinose family oligosaccharides (RFOs), such as raffinose and stachyose, are synthesized by a set of distinct galactosyltransferases, which sequentially add galactose units to sucrose. The accumulation of RFOs in plant cells are closely associated with the responses to environmental factors, such as cold, heat and drought stresses. Systematic analysis of genes involved in the raffinose metabolism has not been reported to date. Searching the recently available working draft of the maize genome, six kinds of enzyme genes were speculated, which should encode all the enzymes involved in the raffinose metabolism in maize. Expression patterns of some related putative genes were analyzed. The conserved domains and phylogenetic relationships among the deduced maize proteins and their homologs isolated from other plant species were revealed. It was discovered that some of the key enzymes, such as galactinol synthase (ZmGolS5, ZmGolS45 and ZmGolS37), raffinose synthase (ZmRS1, ZmRS2, ZmRS3 and ZmRS10), stachyose synthase (ZmRS8) and ß-fructofuranosidase, are encoded by multiple gene members with different expression patterns. These results reveal the complexity of the raffinose metabolism and the existence of metabolic channels for diverse RFOs in maize and provide useful information for improving maize stress tolerance through genetic engineering.


Assuntos
Galactosiltransferases/genética , Genoma de Planta , Rafinose/biossíntese , Zea mays/enzimologia , Dissacarídeos/metabolismo , Galactosiltransferases/química , Galactosiltransferases/metabolismo , Filogenia , Estrutura Terciária de Proteína , Rafinose/metabolismo , Transcrição Gênica , Zea mays/genética , beta-Frutofuranosidase/química , beta-Frutofuranosidase/genética , beta-Frutofuranosidase/metabolismo
15.
Funct Integr Genomics ; 12(4): 683-91, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22983498

RESUMO

Maize (Zea mays ssp. mays L.) is an important model organism for fundamental research in the agro-biotechnology field. Aldehydes were generated in response to a suite of environmental stresses that perturb metabolism including salinity, dehydration, desiccation, and cold and heat shock. Many biologically important aldehydes are metabolized by the superfamily of NAD(P)(+)-dependent aldehyde dehydrogenases. Here, starting from the database of Z. mays, we identified 28 aldehyde dehydrogenase (ALDH) genes and 48 transcripts by the in silico cloning method using the ALDH-conserved domain amino acid sequence of Arabidopsis and rice as a probe. Phylogenetic analysis shows that all 28 members of the ALDH gene families were classified to ten distinct subfamilies. Microarray data and quantitative real-time PCR analysis reveal that ZmALDH9, ZmALDH13, and ZmALDH17 genes involve the function of drought stress, acid tolerance, and pathogens infection. These results suggested that these three ZmALDH genes might be potentially useful in maize genetic improvement.


Assuntos
Aldeído Desidrogenase/genética , Família Multigênica , Zea mays/genética , Aldeído Desidrogenase/química , Bases de Dados de Ácidos Nucleicos , Regulação da Expressão Gênica de Plantas , Filogenia , Estrutura Terciária de Proteína , RNA Mensageiro/biossíntese , Análise de Sequência de DNA , Estresse Fisiológico , Zea mays/enzimologia
16.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 9): o2723, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22969607

RESUMO

The title compound, C(6)HCl(6)N, lies on a mirror plane, the asymmetric unit conataining a half-mol-ecule. Weak intra-molecular C-H⋯Cl contacts are observed.

17.
Int J Ophthalmol ; 15(1): 106-112, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35047364

RESUMO

AIM: To evaluate foveal vessel density (VD) and foveal thickness using optical coherence tomography angiography (OCTA) in retinopathy of prematurity (ROP) children treated with laser photocoagulation or anti-vascular endothelial growth factor (VEGF) injection. Additionally, we assessed the relationship between foveal microvascular anomalies and different therapies in ROP children. METHODS: This was a single-center, retrospective study of patients with a diagnosis of type 1 ROP. Twenty-three eyes (14 patients) treated with anti-VEGF injection and twenty-nine eyes (17 patients) treated with laser coagulation were included in this study. The foveal VD, inner thickness and full thickness were measured at the central 0°, 2° to 8°, and 8° of the retina (centered on the fovea) using OCTA and cross-sectional OCT, respectively. RESULTS: Foveal VD, inner thickness and full thickness were significantly smaller within the central 8° of the retina in ROP children treated with anti-VEGF injection than in those treated with laser photocoagulation (P=0.013, 0.009, 0.036, respectively). The full thickness was also smaller in the anti-VEGF group than in the laser group at the central 0° of the retina (P=0.010). The grade of foveal hypoplasia is lower in the anti-VEGF group than in the laser group (P=0.045). Multivariable analysis did not find any risk factors associated with visual acuity in our study. CONCLUSION: In children with type 1 ROP, the better structural development of fovea in those who were treated with anti-VEGF injection compared with laser photocoagulation are identified. However, visual acuity outcomes are similar 70mo after the treatments.

18.
Int J Ophthalmol ; 15(11): 1814-1820, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36404970

RESUMO

AIM: To evaluate the outcomes of intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents for patients with retinal vein occlusion (RVO) related-macular edema (ME) in Tibetan. METHODS: A retrospective, observational, single-center study. The demographic and clinical data of 90 RVO Tibetan patients (93 eyes) treated with either ranibizumab or conbercept in Tibet Autonomous Region People's Hospital from Jan 2018 to December 2019 were collected. RESULTS: The mean patient age was 56.8±10.6y, 45 (50%) of them were female. The mean living altitude was 3867.8±567.9 m. At the last visit, the best-corrected visual acuity (BCVA) significantly increased (52.2±21.8 letters) in comparison with the baseline (38.2±24.1 letters, P<0.001); while the central retinal thickness (CRT) significantly reduced (245.5±147.6 µm) in comparison with the baseline (504.1±165.2 µm, P<0.001). The 43.0% of the eyes gained ≥15 letters, 60.2% of the eyes gained ≥10 letters, and 78.5% of the eyes gained ≥5 letters. No vision loss was noted in 92.5% of the eyes, 4 eyes lost more than 10 letters during follow-up period. The mean number of injections was 2.4±1.8. No severe ocular or systemic adverse events related to either the drug or injection were noted. CONCLUSION: Anti-VEGF therapy is effective and safe in Tibetan patients for the treatment of RVO related ME.

19.
Huan Jing Ke Xue ; 43(8): 4253-4261, 2022 Aug 08.
Artigo em Zh | MEDLINE | ID: mdl-35971721

RESUMO

Taraxacum kok-saghyz Rodin (TSK) is an energy plant that can be used as a raw material for natural rubber. The aim of this study was to examine the remediation potential of TSK to lead (Pb)- and cadmium (Cd)-contaminated farmland soil. In this study, a pot experiment was conducted, and the "Soil Environmental Quality and Agricultural Land Soil Pollution Risk Control Standard (GB 15618-2018)" was used as reference. We set up four different concentrations of Pb and Cd pollution treatment to study the characteristics of the accumulation and tolerance of TSK to Pb and Cd. The results showed that as the content of Pb and Cd in the soil increased, the chlorophyll content and biomass of TSK gradually decreased, and the SOD, POD, and CAT enzyme activities gradually increased. The BCF and TF of Cd were between 1.20 and 1.50, indicating that TSK presented some characteristics of a Cd hyperaccumulator. The BCF and TF of Pb were between 0.71 and 1.11. Thus, TSK was a good Pb enrichment plant and possessed the potential to repair soil with ω(Pb) below 400 mg·kg-1. The accumulation of Pb and Cd gradually increased, and the maximum accumulation of Cd and Pb in the shoots was 9.832 µg·plant-1 and 1091.185 µg·plant-1, respectively. However, in lower concentrations of Pb- and Cd-contaminated soil, the removal rate was greater, and the remediation efficiency was better. Overall, using TSK to repair Pb- and Cd-contaminated farmland soil has good application prospects and economic value.


Assuntos
Poluentes do Solo , Taraxacum , Biodegradação Ambiental , Cádmio/análise , Fazendas , Chumbo , Plantas , Solo , Poluentes do Solo/análise
20.
Appl Microbiol Biotechnol ; 90(4): 1229-39, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21468707

RESUMO

In the past three decades, hairy roots research for the production of valuable biological active substances has received a lot of attention. The addition of knowledge to enhance the yields of desired substances and the development of novel tools for biomass engineering offer new possibilities for large-scale cultivation of the plant hairy root. Hairy roots can also produce recombinant proteins through the transfer of Agrobacterium T-DNA into the plant genome, and thereby hold immense potential for the pharmaceutical industry. This review highlights some of the significant progress made in the past few years and outlines future prospects for exploiting the potential utility of hairy root cultures as "chemical factories" for producing bioactive substances.


Assuntos
Fatores Biológicos/metabolismo , Engenharia Genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Fatores Biológicos/genética , Células Cultivadas , Raízes de Plantas/genética , Plantas Geneticamente Modificadas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
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