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1.
Org Lett ; 25(12): 2036-2040, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36926952

RESUMO

Determining the chirality of phosphoric acids can be a challenging task. In this study, we present a novel approach for the chiral recognition of phosphates using cationic octahedral cobalt complexes. By utilizing 31P NMR spectroscopy, we are able to accurately measure the enantiopurities of chiral phosphoric acids after forming ion pairs with the cobalt complexes. We have successfully applied this method to a variety of chiral phosphoric acids derived from BINOL, H8-BINOL, SPINOL, VAPOL, and VANOL compounds, as well as ATP, and were able to efficiently resolve them in 31P{1H} NMR spectra. Furthermore, we were able to achieve an optical resolution of a phosphoric acid with an enantiomeric excess of greater than 99%.

2.
Chem Sci ; 13(4): 1169-1176, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35211284

RESUMO

Control over chemo- and regioselectivity is a critical issue in the heterobiaryl synthesis via C-H oxidative coupling. To address this challenge, a strategy to invert the normal polarity of indoles in the heterobiaryl coupling was developed. With N-carboxyindoles as umpoled indoles, an exclusively ortho-selective coupling with phenols has been realized, employing a Brønsted acid- or Cu(i)-catalyst (as low as 0.01 mol%). A range of phenols and N-carboxyindoles coupled with exceptional efficiency and selectivity at ambient temperature and the substrates bearing redox-active aryl halides (-Br and -I) smoothly coupled in an orthogonal manner. Notably, preliminary examples of atropselective heterobiaryl coupling have been demonstrated, based on a chiral disulfonimide or a Cu(i)/chiral bisphosphine catalytic system. The reaction was proposed to occur through SN2' substitution or a Cu(i)-Cu(iii) cycle, with Brønsted acid or Cu(i) catalysts, respectively.

3.
J Environ Pathol Toxicol Oncol ; 39(4): 299-308, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33389902

RESUMO

Vernolide-A and vernodaline are sesquiterpene lactones isolated from genera of Vernonia. Vernolide-A and vernodaline have shown promising therapeutic properties, including antibacterial, antihelminth, and antioxidant activities. Recently, the anticancer properties of these sesquiterpene lactones have been investigated with the elucidation of effects on cell proliferation, metastasis, angiogenesis, and apoptosis. The antiproliferation and antimetastatic activities arise from targeting extracellular signal-regulated kinase 1 (ERK-1), extracellular signal-regulated kinase 2 (ERK-2), nuclear factor-κB (NF-κB), signal transducer and activator of transcription 3 (STAT3), matrix metalloproteinase 2 (MMP-2), and matrix metalloproteinase 9 (MMP9). The induction of apoptosis is due to the enhancement of caspase 9, caspase 3, while inhibition of Bcl-2 and Bcl-xL results in the release of cytochrome c into the cytosol. The activity of vernolide-A and vernodaline is hypothesized to be due to thiol reactivity through the α-methylene-γ-lactone group of sesquiterpene lactones. This review will give a brief summary of the anticancer activity of vernolide-A and vernodaline and provide information on the underlying molecular mechanisms.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Lactonas/farmacologia , Sesquiterpenos/farmacologia , Vernonia/química , Inibidores da Angiogênese/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Sesquiterpenos/toxicidade
4.
RSC Adv ; 10(73): 44743-44746, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-35516277

RESUMO

A simple method for coupling of anilines, acetophenones, and elemental sulfur to afford N-arylthioglyoxamides has been developed. Reactions proceeded in the presence of Na2SO3 and DMSO, thus eliminating the need for transition metals and external oxidants. Functionalities such as halogen, ester, methylthio, and heterocycle groups were compatible with the conditions. Electron-poor acetophenones sometimes gave isosteric glyoxamides.

5.
Chem Sci ; 10(38): 8799-8805, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31803452

RESUMO

Oxidative coupling of 1,3-enynamides using DMSO as a terminal oxidant has been developed. Carbon as well as unmodified heteroatom nucleophiles, including aliphatic alcohols, thiols, and hydrazides, could be efficiently alkylated at the γ-position in a highly regioselective fashion. The kinetic analysis suggested a nucleophile-dependent mechanism ranging from a concerted SN2'' to a carbocationic mechanism. Thus, the remote site-selectivity was ascribed to the partial positive charge developing at the terminal carbocationic center.

6.
Org Lett ; 21(22): 9009-9013, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31692359

RESUMO

Oxidation of ynamides by mCPBA led to ß-oxygenation and resulted in formation of carbonyl compounds with α-N,O-acetal functionality. These N,O-acetals are formed in high yields and can be stored indefinitely at room temperature. Yet, they can be activated by a chiral Brønsted acid and underwent an enantioselective transacetalization into a α-N,O-acetal. Subsequent diastereoselective transformations occurred with exceptional selectivity according to Felkin-Anh model.

7.
Inflammopharmacology ; 27(5): 871-883, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31407196

RESUMO

Ginseng has been traditionally used as an herbal nutritional supplement in Asian countries, including Korea, China, Japan, and Vietnam for several millennia. Most studies have focused on the role of ginseng on anti-oxidative stress, anti-inflammatory, and anti-cancer activities. Recently, modulator activities of ginseng on the immune responses during pathogenic bacterial and viral infections and beneficial effects of ginseng in infectious diseases have been elucidated. In vivo and in vitro studies revealed the potential of ginseng extracts and ginsenosides Rg1, Rg3, Rb1, Rb2, Rb3, compound K, Re, Rd, Rh2 for treatment of several infectious diseases. The molecular mechanisms of these effects mainly involve inflammatory cytokines (TNF-α, IL-6, IL-1ß, IFN-γ, IL-10), apoptotic pathway (bcl-2, bcl-xL), PI3K/Akt pathway, MAPKs pathway, JAK2/STAT5, NF-κB pathway, and the inflammasome. In this review, we will summarize the current knowledge on the effects of ginseng in the immune responses during the infections and its bioactivities on the prevention of infectious diseases as well as its underlying mechanisms. Moreover, the therapeutic potential of ginseng as an anti-bacterial and anti-viral medication and vaccine adjuvant will be discussed as well.


Assuntos
Doenças Transmissíveis/tratamento farmacológico , Ginsenosídeos/farmacologia , Panax/química , Animais , Doenças Transmissíveis/metabolismo , Citocinas/metabolismo , Humanos , Imunidade/efeitos dos fármacos , Inflamação/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos
9.
J Matern Fetal Neonatal Med ; 32(23): 4009-4015, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29865915

RESUMO

Objective: Noninvasive prenatal testing (NIPT) for fetal aneuploidies has been widely adopted in developed countries. Despite the sharp decrease in the cost of massively parallel sequencing, the technical know-how and skilled personnel are still one of the major limiting factors for applying this technology to NIPT in low-income settings. Here, we present the establishment and validation of our NIPT procedure called triSure for detection of fetal aneuploidies. Methods: We established the triSure algorithm based on the difference in proportion of fetal and maternal fragments from the target chromosome to all chromosomes. Our algorithm was validated using a published data set and an in-house data set obtained from high-risk pregnant women in Vietnam who have undergone amniotic testing. Several other aneuploidy calling methods were also applied to the same data set to benchmark triSure performance. Results: The triSure algorithm showed similar accuracy to size-based method when comparing them using published data set. Using our in-house data set from 130 consecutive samples, we showed that triSure correctly identified the most samples (overall sensitivity and specificity of 0.983 and 0.986, respectively) compared to other methods tested including count-based, sized-based, RAPIDR and NIPTeR. Conclusions: We have demonstrated that our triSure NIPT procedure can be applied to pregnant women in low-income settings such as Vietnam, providing low-risk screening option to reduce the need for invasive diagnostic tests.


Assuntos
Aneuploidia , Ácidos Nucleicos Livres/análise , Teste Pré-Natal não Invasivo/métodos , Adulto , Algoritmos , Estudos de Casos e Controles , Ácidos Nucleicos Livres/sangue , Cromossomos Humanos Par 13/genética , Cromossomos Humanos Par 18/genética , Cromossomos Humanos Par 21/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Pessoa de Meia-Idade , Gravidez , Análise de Sequência de DNA/métodos , Trissomia/diagnóstico , Trissomia/genética , Vietnã , Adulto Jovem
10.
BMC Med Genet ; 19(1): 188, 2018 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-30340471

RESUMO

BACKGROUND: Familial adenomatous polyposis (FAP) is an autosomal dominant hereditary syndrome characterised by the development of hundreds to thousands of adenomatous colonic polyps during the second decade of life. FAP is caused by germ line mutations in the adenomatous polyposis coli (APC) gene located on chromosome 5q21-22. CASE PRESENTATION: A 36-year-old female was presented with 100-1000 adenomatous colonic polyps, typical of classic FAP symptoms. Genetic testing using massively parallel sequencing identified a 5-bp deletion (c.3927_3931delAAAGA) which causes frameshift (p.Glu1309Aspfs) and creates a premature stop codon, resulting in the replacement of the last 1535 amino acids of APC by five incorrect amino acids. Two of the proband's four siblings also exhibited classic FAP symptoms and carried the same 5-bp heterozygous deletion in the APC gene. One of the proband's two nephews also tested positive for this mutation but has not been examined by endoscopy due to his young age. CONCLUSIONS: We reported here for the first time the use of massively parallel sequencing (MPS)-based genetic testing to identify a germline mutation within a three-generation Vietnamese family. This mutation is most likely responsible for the development of FAP.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/diagnóstico , Polipose Adenomatosa do Colo/genética , Mutação da Fase de Leitura , Heterozigoto , Polipose Adenomatosa do Colo/etnologia , Polipose Adenomatosa do Colo/cirurgia , Adulto , Povo Asiático , Pré-Escolar , Cromossomos Humanos Par 5/química , Colectomia/métodos , Feminino , Expressão Gênica , Testes Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Irmãos , Vietnã
11.
Front Genet ; 9: 127, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29719550

RESUMO

The genetic resources available for the commercially important fish species Yellowtail kingfish (YTK) (Seriola lalandi) are relative sparse. To overcome this, we aimed (1) to develop a linkage map for this species, and (2) to identify markers/variants associated with economically important traits in kingfish (with an emphasis on body weight). Genetic and genomic analyses were conducted using 13,898 single nucleotide polymorphisms (SNPs) generated from a new high-throughput genotyping by sequencing platform, Diversity Arrays Technology (DArTseqTM) in a pedigreed population comprising 752 animals. The linkage analysis enabled to map about 4,000 markers to 24 linkage groups (LGs), with an average density of 3.4 SNPs per cM. The linkage map was integrated into a genome-wide association study (GWAS) and identified six variants/SNPs associated with body weight (P < 5e-8) when a multi-locus mixed model was used. Two out of the six significant markers were mapped to LGs 17 and 23, and collectively they explained 5.8% of the total genetic variance. It is concluded that the newly developed linkage map and the significantly associated markers with body weight provide fundamental information to characterize genetic architecture of growth-related traits in this population of YTK S. lalandi.

12.
BMC Genet ; 19(1): 27, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29728054

RESUMO

BACKGROUND: One of the major impediments to spiny lobster aquaculture is the high cost of hatchery production due to the long and complex larval cycle and poor survival during the many moult stages, especially at metamorphosis. We examined if the key trait of larval survival can be improved through selection by determining if genetic variance exists for this trait. Specifically, we report, for the first time, genetic parameters (heritability and correlations) for early survival rates recorded at five larval phases; early-phyllosoma stages (instars 1-6; S1), mid-phyllosoma stages (instars; 7-12; S2), late-phyllosoma stages (instars 13-17; S3), metamorphosis (S4) and puerulus stage (S5) in hatchery-reared spiny lobster Sagmariasus verreauxi. RESULTS: The data were collected from a total of 235,060 larvae produced from 18 sires and 30 dams over nine years (2006 to 2014). Parentage of the offspring and full-sib families was verified using ten microsatellite markers. Analysis of variance components showed that the estimates of heritability for all the five phases of larval survival obtained from linear mixed model were generally similar to those obtained from threshold logistic generalised models (0.03-0.47 vs. 0.01-0.50). The heritability estimates for survival traits recorded in the early larval phases (S1 and S2) were higher than those estimated in later phases (S3, S4 and S5). The existence of the additive genetic component in larval survival traits indicate that they could be improved through selection. Both phenotypic and genetic correlations among the five survival measures studied were moderate to high and positive. The genetic associations between successive rearing periods were stronger than those that are further apart. CONCLUSIONS: Our estimates of heritability and genetic correlations reported here in a spiny lobster species indicate that improvement in the early survival especially during metamorphosis can be achieved through genetic selection in this highly economic value species.


Assuntos
Metamorfose Biológica/genética , Palinuridae/crescimento & desenvolvimento , Palinuridae/genética , Animais , Aquicultura , Hereditariedade , Larva/crescimento & desenvolvimento , Seleção Genética
13.
BMC Genomics ; 19(1): 107, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29382299

RESUMO

BACKGROUND: Genomic prediction using Diversity Arrays Technology (DArT) genotype by sequencing platform has not been reported in yellowtail kingfish (Seriola lalandi). The principal aim of this study was to address this knowledge gap and to assess predictive ability of genomic Best Linear Unbiased Prediction (gBLUP) for traits of commercial importance in a yellowtail kingfish population comprising 752 individuals that had DNA sequence and phenotypic records for growth traits (body weight, fork length and condition index). The gBLUP method was used due to its computational efficiency and it showed similar predictive performance to other approaches, especially for traits whose variation is of polygenic nature, such as body traits analysed in this study. The accuracy or predictive ability of the gBLUP model was estimated for three growth traits: body weight, folk length and condition index. RESULTS: The prediction accuracy was moderate to high (0.44 to 0.69) for growth-related traits. The predictive ability for body weight increased by 17.0% (from 0.69 to 0.83) when missing genotype was imputed. Within population prediction using five-fold across validation approach showed that the gBLUP model performed well for growth traits (weight, length and condition factor), with the coefficient of determination (R2) from linear regression analysis ranging from 0.49 to 0.71. CONCLUSIONS: Collectively our results demonstrated, for the first time in yellowtail kingfish, the potential application of genomic selection for growth-related traits in the future breeding program for this species, S. lalandi.


Assuntos
Peixes/genética , Genômica , Animais , Peso Corporal/genética , Peixes/crescimento & desenvolvimento , Técnicas de Genotipagem , Fenótipo
14.
Front Genet ; 8: 82, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28659970

RESUMO

The extent to which genetic gain achieved from selection programs under strictly controlled environments in the nucleus that can be expressed in commercial production systems is not well-documented in aquaculture species. The main aim of this paper was to assess the effects of genotype by environment interaction on genetic response and genetic parameters for four body traits (harvest weight, standard length, body depth, body width) and survival in Red tilapia (Oreochromis spp.). The growth and survival data were recorded on 19,916 individual fish from a pedigreed population undergoing three generations of selection for increased harvest weight in earthen ponds from 2010 to 2012 at the Aquaculture Extension Center, Department of Fisheries, Jitra in Kedah, Malaysia. The pedigree comprised a total of 224 sires and 262 dams, tracing back to the base population in 2009. A multivariate animal model was used to measure genetic response and estimate variance and covariance components. When the homologous body traits in freshwater pond and cage were treated as genetically distinct traits, the genetic correlations between the two environments were high (0.85-0.90) for harvest weight and square root of harvest weight but the estimates were of lower magnitudes for length, width and depth (0.63-0.79). The heritabilities estimated for the five traits studied differed between pond (0.02 to 0.22) and cage (0.07 to 0.68). The common full-sib effects were large, ranging from 0.23 to 0.59 in pond and 0.11 to 0.31 in cage across all traits. The direct and correlated responses for four body traits were generally greater in pond than in cage environments (0.011-1.561 vs. -0.033-0.567 genetic standard deviation units, respectively). Selection for increased harvest body weight resulted in positive genetic changes in survival rate in both pond and cage culture. In conclusion, the reduced selection response and the magnitude of the genetic parameter estimates in the production environment (i.e., cage) relative to those achieved in the nucleus (pond) were a result of the genotype by environment interaction and this effect should be taken into consideration in the future breeding program for Red tilapia.

15.
Food Chem ; 217: 593-601, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27664676

RESUMO

Ultrasonication (US) of whole milk at 22.5kHz and 50W homogenized fat globules. Extended US without temperature control (attaining >90°C at longest times), or with control at temperatures ⩾60°C caused denaturation of the whey proteins and aggregation of the fat globules and proteins. Acidification of US milk produced gels with increased firmness and reduced gelation times compared to untreated milk. Below 60°C, US of milk produced acid gels with very high firmness without whey protein denaturation; the firmness was similar to gels from heated whole milk. Extensive US without temperature control or with control at ⩾60°C decreased acid gel firmness compared to shorter times or lower temperatures. Higher acid gel firmness could be achieved by subjecting the milk to separate heat (80°C/30min) and US treatment (at 20°C) before acidification when compared with either heating or US alone. This was independent of the order of heating and US treatment.


Assuntos
Manipulação de Alimentos , Géis/química , Leite/química , Ultrassom , Animais , Gorduras na Dieta/análise , Temperatura Alta , Tamanho da Partícula , Desnaturação Proteica , Reologia , Proteínas do Soro do Leite/análise
16.
Dev Cell ; 34(5): 493-504, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26321127

RESUMO

Postnatal organogenesis occurs in an immune competent environment and is tightly controlled by interplay between positive and negative regulators. Innate immune cells have beneficial roles in postnatal tissue remodeling, but roles for the adaptive immune system are currently unexplored. Here we show that adaptive immune responses participate in the normal postnatal development of a non-lymphoid epithelial tissue. Since the mammary gland (MG) is the only organ developing predominantly after birth, we utilized it as a powerful system to study adaptive immune regulation of organogenesis. We found that antigen-mediated interactions between mammary antigen-presenting cells and interferon-γ (IFNγ)-producing CD4+ T helper 1 cells participate in MG postnatal organogenesis as negative regulators, locally orchestrating epithelial rearrangement. IFNγ then affects luminal lineage differentiation. This function of adaptive immune responses, regulating normal development, changes the paradigm for studying players of postnatal organogenesis and provides insights into immune surveillance and cancer transformation.


Assuntos
Imunidade Adaptativa/imunologia , Células Apresentadoras de Antígenos/imunologia , Mama/imunologia , Células Epiteliais/citologia , Epitélio/metabolismo , Organogênese/imunologia , Animais , Células Apresentadoras de Antígenos/citologia , Mama/crescimento & desenvolvimento , Mama/metabolismo , Células Epiteliais/imunologia , Epitélio/imunologia , Feminino , Humanos , Imunidade Inata/imunologia , Interferon gama/metabolismo , Camundongos
17.
Proc Natl Acad Sci U S A ; 112(34): E4642-50, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26253763

RESUMO

Small autonomous machines like biological cells or soft robots can convert energy input into control of function and form. It is desired that this behavior emerges spontaneously and can be easily switched over time. For this purpose we introduce an active matter system that is loosely inspired by biology and which we term an active colloidal cell. The active colloidal cell consists of a boundary and a fluid interior, both of which are built from identical rotating spinners whose activity creates convective flows. Similarly to biological cell motility, which is driven by cytoskeletal components spread throughout the entire volume of the cell, active colloidal cells are characterized by highly distributed energy conversion. We demonstrate that we can control the shape of the active colloidal cell and drive compartmentalization by varying the details of the boundary (hard vs. flexible) and the character of the spinners (passive vs. active). We report buckling of the boundary controlled by the pattern of boundary activity, as well as formation of core-shell and inverted Janus phase-separated configurations within the active cell interior. As the cell size is increased, the inverted Janus configuration spontaneously breaks its mirror symmetry. The result is a bubble-crescent configuration, which alternates between two degenerate states over time and exhibits collective migration of the fluid along the boundary. Our results are obtained using microscopic, non-momentum-conserving Langevin dynamics simulations and verified via a phase-field continuum model coupled to a Navier-Stokes equation.

18.
Soft Matter ; 10(26): 4593-602, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-24700306

RESUMO

We investigate the phase behavior of short-range interacting isotropic particles and single-patch Janus particles via simulations of sedimentation equilibrium, which allows for a rapid assessment of the equation of state and phase behavior directly from simulation. The methodology is tested against results by traditional methods and is found to yield good agreement for isotropic interactions. The method is then used to study single-patch Janus particles with different interaction strengths and patch sizes with particle area coverage greater than ∼0.63. Our results show an interplay between translational and orientational order. We observe a lamellar phase, a fluid phase and a rotator close-packed structure. The lamellar phase is shown to have a different range of stability than previously observed in simulation studies for systems of similar and longer-ranged interactions.

19.
Phys Rev Lett ; 112(7): 075701, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24579615

RESUMO

We investigate collective phenomena with rotationally driven spinners of concave shape. Each spinner experiences a constant internal torque in either a clockwise or counterclockwise direction. Although the spinners are modeled as hard, otherwise noninteracting rigid bodies, their active motion induces an effective interaction that favors rotation in the same direction. With increasing density and activity, phase separation occurs via spinodal decomposition, as well as self-organization into rotating crystals. We observe the emergence of cooperative, superdiffusive motion along interfaces, which can transport inactive test particles. Our results demonstrate novel phase behavior of actively rotated particles that is not possible with linear propulsion or in nondriven, equilibrium systems of identical hard particles.


Assuntos
Modelos Teóricos , Rotação , Movimento Celular/fisiologia , Cinética , Torque
20.
Food Chem ; 138(2-3): 1604-9, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23411287

RESUMO

Skim milk with low levels of added ß-mercaptoethanol (SM-ME) and untreated skim milk (SM) were heated and then made into acid gels. Acid gels prepared from heated SM-ME had markedly higher firmness and contained more protein connections than acid gels prepared from heated SM. Electrophoretic analyses of the milks showed that the levels of ß-lactoglobulin and α-lactalbumin associated with the casein micelles increased with increasing ß-ME concentration. The levels of disulphide-linked whey proteins were higher in SM-ME than in SM. This suggested that there may be higher levels of initiators for thiol-disulphide exchange reactions, resulting in an increase in the rate of the reactions and the formation of greater numbers of small aggregates, in SM-ME than in SM. Consequently, acid gels made from SM-ME may have more bonds and more particles participating in the network, resulting in firmer gels, than acid gels made from SM.


Assuntos
Mercaptoetanol/química , Proteínas do Leite/química , Leite/química , Substâncias Redutoras/química , Animais , Bovinos , Manipulação de Alimentos , Temperatura Alta , Ligação Proteica , Reologia , Proteínas do Soro do Leite
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