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1.
Zootaxa ; 5403(2): 279-286, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38480442

RESUMO

A new species, Schizosthetus baixuelii sp. nov., is described based on females from Ningxia Hui Autonomous Region, China. A key to the known species of the genus is presented.


Assuntos
Ácaros , Feminino , Animais , China
2.
Br J Radiol ; 96(1152): 20230338, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37750852

RESUMO

OBJECTIVE: Resting-state functional magnetic resonance imaging (rs-fMRI) and Granger causality analysis (GCA) were used to observe the characteristics of amygdala and whole-brain effect connections in patients with herpes zoster (HZ) and post-herpetic neuralgia (PHN) and to determine their relationship with clinical features. METHODS: Rs-fMRI scans were performed on 50 HZ; 50 PHN; and 50 age-, sex- and education-year-matched healthy controls (HCs). Bilateral amygdala subregions were used as seeds for functional connectivity (FC). GCA was used to analyze the effective connection of brain regions that were significantly different among groups. Then, the correlation between FC, and GCA values and clinical indices was investigated. RESULTS: PHN had impaired FC between the amygdala subregion with the putamen, cortex, anterior cingulate cortex (ACC) to HCs and reduced FC of medial amygdala (MeA) with the parieto-occipital lobe and motor cortex to HZ; HZ had reduced FC of the lateral amygdala (LA) with the insula to HCs. GCA values from the bilateral LA to the bilateral ACC, left MeA to the bilateral ACC and left putamen, and right ACC to the bilateral MeA were reduced in PHN patients compared to HCs. Compared with HCs, the GCA values from the left MeA to the left ACC and right putamen were reduced in HZ. The GCA values from the amygdala subregion to the ACC were positively correlated with HAMA or HAMD scores in PHN. CONCLUSION: PHN showed reduced FC between the amygdala subregions and cortico-putamen and decreased effective connectivity from the amygdala subregion to the ACC and putamen. ADVANCES IN KNOWLEDGE: HZ and PHN patients had significant changes in effective connectivity in brain regions, including diverse functional areas emanating from and projecting to the amygdala. The current findings will provide a new perspective for understanding the neuropathophysiological mechanism HZ and PHN.


Assuntos
Herpes Zoster , Neuralgia Pós-Herpética , Humanos , Neuralgia Pós-Herpética/diagnóstico por imagem , Encéfalo , Herpes Zoster/complicações , Herpes Zoster/diagnóstico por imagem , Mapeamento Encefálico , Tonsila do Cerebelo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
3.
Zootaxa ; 5092(3): 387-395, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35391198

RESUMO

This study provides the first description of the male of Proparholaspulus ishikawai Liang Hu, 1993, on the basis of specimens from the south of China. The leg chaetotaxy of Proparholaspulus is described for the first time. A key for all recognisable species of Proparholaspulus is provided.


Assuntos
Ácaros e Carrapatos , Ácaros , Animais , Masculino , Comportamento Predatório
4.
Stem Cell Res ; 43: 101702, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32007762

RESUMO

A 66-year old mild cognitive impairment (MCI) female patient donated her Peripheral blood mononuclear cells (PBMC). PBMC was reprogrammed using non-integrative Sendai viral vectors containing reprogramming factors OCT4, KLF4, SOX2 and C-MYC. The pluripotency of transgene-free iPSCs was confirmed by immunocytochemistry and ability of differentiation spontaneously into 3 germ layers in vitro. Moreover, the iPSC line displayed a normal karyotype. The apolipoprotein E (APOE) ε4 allele, is considered to be the strongest genetic risk factor for Sporadic Alzheimer's disease (AD). Our model might offer a good platform to study the pathological mechanisms and drug testing studies in AD and MCI.


Assuntos
Apolipoproteína E4/genética , Disfunção Cognitiva/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Idoso , Feminino , Humanos , Fator 4 Semelhante a Kruppel
5.
Acta Biochim Biophys Sin (Shanghai) ; 40(8): 711-20, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18685787

RESUMO

A combination of extrinsic hematopoietic growth regulators, such as stem cell factor (SCF), interleukin (IL)-3 and IL-6, can induce division of quiescent hematopoietic stem cells (HSCs), but it usually impairs HSCs' self-renewal ability. However, intrinsic negative cell cycle regulators, such as p18INK4C (p18), p27Kip1 (p27) and MAD1, can regulate the self-renewal of HSCs. It is unknown whether the removal of some extrinsic regulators and the knockdown of intrinsic negative cell cycle regulators via RNA interference (RNAi) induce ex vivo expansion of the HSCs. To address this question, a lentiviral vector-based RNAi tool was developed to produce two copies of small RNA that target multiple genes to knockdown the intrinsic negative cell cycle regulators p18, p27 and MAD1. Colony-forming cells, long-term culture-initiating cells (LTC-IC) and engraftment assays were used to evaluate the effects of extrinsic and intrinsic regulators. Results showed that the medium with only SCF, but without IL-3 and IL-6, could maintain the sca-1+c-kit+ bone marrow cells with high LTC-IC frequency and low cell division. However, when the sca-1+c-kit+ bone marrow cells were cultured in a medium with only SCF and simultaneously knocked down the expression of p18, p27 and MAD1 via the lentiviral vector-based RNAi, the cells exhibited both high LTC-IC frequency and high cell division, though engraftment failed. Thus, the simultaneous knockdown of p18, p27 and MAD1 with a medium of only SCF can induce LTC-IC expansion despite the loss of engraftment ability.


Assuntos
Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Proteínas de Ciclo Celular/antagonistas & inibidores , Inibidor de Quinase Dependente de Ciclina p18/antagonistas & inibidores , Inibidor de Quinase Dependente de Ciclina p27/antagonistas & inibidores , Proteínas Nucleares/antagonistas & inibidores , Animais , Sequência de Bases , Células da Medula Óssea/efeitos dos fármacos , Transplante de Medula Óssea , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Inibidor de Quinase Dependente de Ciclina p18/deficiência , Inibidor de Quinase Dependente de Ciclina p18/genética , Inibidor de Quinase Dependente de Ciclina p27/deficiência , Inibidor de Quinase Dependente de Ciclina p27/genética , DNA Complementar/genética , Feminino , Vetores Genéticos , Hematopoese/genética , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Lentivirus/genética , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Fator de Células-Tronco/farmacologia
6.
Talanta ; 54(2): 411-6, 2001 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-18968266

RESUMO

Standard methods for peroxide value determination in edible oils, which are based on KI oxidation by the hydroperoxides and volumetric titration of the liberated iodine, have been improved using redox-potentiometric iodine determination without titration. Stages of the KI oxidation and redox-potentiometric measurements were combined in the same electrochemical cell. The limit of quantitation of the new method is 0.16 meq kg(-1), which allows the analysis of fresh refined oils. The method is simple, not time and labor consuming, and suitable for automation.

7.
J AOAC Int ; 83(2): 282-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10772165

RESUMO

A pH-metric method was developed for determination of the acid numbers of oils containing organic and inorganic acids at levels <0.1 mg KOH/g oil. The method is based on rapid and complete extraction of acids from a test portion of oil into a special reagent, and measurement of the conditional pH of the mixture "oil-reagent" by a glass electrode. The method uses nontoxic reagents, is not time and labor consuming, and is cheap and simple enough for automation.


Assuntos
Petróleo , Eletrodos , Vidro , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Talanta ; 49(3): 629-37, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18967639

RESUMO

A new pH-metric method for determination of acid values in oilseeds without titration has been developed in the range 0.6-10 and more mg KOH/g. The method is based on a rapid (1-2 min) selective and complete extraction of free fatty acids from an oilseed test portion into a special reagent A, separation of the solution from the solid oilseed material by centrifugation or filtration, transfer of an aliquot of the solution into a pH-metric cell with reagent B for measurement of conditional pH(1)' of the formed mixture, addition of standard acid (HCl or H(2)SO(4)) and pH(2)' measurement. The reagents are non-toxic, and the method is rapid. Its metrological parameters for Soybean, Canola and Sunflower oilseeds are satisfactory for practical purposes.

9.
Talanta ; 50(5): 1135-9, 1999 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-18967808

RESUMO

A heptane-mediated extraction of acids from hydraulic oils is proposed for pH-metric acid number determination without titration. The acids are extracted in the reagent consisting of triethanolamine and potassium nitrate dissolved in water and isopropanol. The use of heptane allows us to overcome the influence of additives in the hydraulic oil on the glass electrode. Simultaneously the extraction of acids from the oil into the water-isopropanol phase is simplified. The method is validated and suitable metrological characteristics of the acid number determination are obtained.

10.
J AOAC Int ; 81(4): 873-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9680713

RESUMO

The acid value (AV) of vegetable oils is determined without titration by using a new reagent consisting of triethanolamine in a solution of water and isopropyl alcohol. When the oil sample is mixed with the reagent in the pH-metric cell, free fatty acids from the sample are extracted into the reagent (3-4 min). The initial pH, called conditional pH'1, is measured, a standard acid (HCl) is added, and the final pH, pH'2, is measured. AV is calculated from the difference between pH'1 and pH'2. The method is applicable for quality control of vegetable oils during their production, trade, and use.


Assuntos
Óleos de Plantas/análise , 2-Propanol , Etanolaminas , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Controle de Qualidade , Padrões de Referência
11.
Talanta ; 47(1): 53-8, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18967302

RESUMO

A new pH-metric method without titration has been developed for determination of acid numbers lower than 0.1 mg (KOH) g(-1) (oil) in petroleum oils such as White, Transformer and Basic oils. The method is based on rapid and complete extraction of acids from an oil test portion into the novel reagent and measurement of the conditional pH in the ;oil-reagent' mixture by a glass electrode. The method has a quantitation limit equal to 1x10(-3) mg (KOH) g(-1) (oil), uses non-toxic reagents, is not time and labor consuming, and is cheap and simple for automation.

12.
Talanta ; 44(1): 1-13, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18966710

RESUMO

The designs and applications of "non-flow" microcells in voltammetry and stripping voltammetry for samples with volumes from sub-microliters to 5 ml are reviewed. The analysis of microcell designs was carried out on the basis of their classification: (i) microcells with a static sample, including thin-layer microcells with a static sample; (ii) microcells with forced convection of the sample; and (iii) microcells for batch injection of samples. Two working electrode types (the usual state and inverted state) are discussed. The use of working micro- and mercury-film electrodes and of the accelerated removal of dissolved oxygen are also considered in detail.

13.
Talanta ; 44(10): 1923-8, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18966935

RESUMO

Anodic voltammetric method for simultaneous determination of uric acid (UA) and ascorbic acid (AA) in urine has been developed with the use of a commercial working rotating glassy carbon electrode. UA may be determined in a sample diluted by the buffer supporting electrolyte (HOAc+NH(4)OH; pH 5.1-5.2) approximately 100 times, and AA-in a sample diluted approximately 20 times. Before obtaining the analytical signal the electrode should be maintained in the diluted sample during 3 min at potential 0 V and the working electrode rotating 100 rpm, for achievement of the adsorption equilibrium of inhibitors from the urine matrix. For UA the electron transfer is close to reversible, for AA it is an irreversible one. Optimal voltammetric techniques are the square-wave for UA and the differential pulse for AA. Calibration curves, detection limits and recoveries for both determinations were evaluated as satisfactory.

14.
Anal Bioanal Chem ; 354(4): 410-3, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15048423

RESUMO

A microcell for batch injection stripping voltammetry of trace metals with the use of a rotating disk working electrode has been developed and tested for samples of 0.2-0.3 mL. The detection limits for Pb(2+), Cd(2+) and Zn(2+) are 0.03 ppb and 0.3 for a deposition time of 5.0 and 0.5 min, respectively.

15.
Talanta ; 42(4): 507-17, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18966258

RESUMO

Methods for determination of titratable acidity, other than traditional titration, i.e. methods without titration, are considered. A number of them use analytical acid-base reagents which quickly convert a mixture of strong and weak acids into a new system. This conversion makes it possible to obtain directly the analytical signal (pH, optical density, etc.) for titratable acidity calculation. These methods in stationary conditions and in flow injection analysis are discussed. Methods not using acid-base reagent (iodide-iodate, chromatographic, spectroscopic and others) are also described. The advantages of the alternative methods such as the decrease labour-consumption and analysis time, simplicity of automation and others are shown.

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