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1.
J Food Sci Technol ; 54(12): 3928-3935, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29085135

RESUMO

Rice vermicelli is a main food consumed in China and Southeast Asia. Quality of rice vermicelli varies with rice cultivars. Parameters including amylose content, amylopectin distribution, thermal and pasting characteristics, gel texture and starch granules of three rice cultivars "Zhongjiazao 17", "Xiangzaoxian 24" and "Thai Jasmine Rice", were studied for their impacts on vermicelli quality. Results showed significant differences for the measurements of the quality traits and indicated that a favorable quality of vermicelli was not determined by any single factor instead of a combination of multi-parameters. A vermicelli with a favorable quality could be produced from a rice variety with a high apparent amylose content (>25%), a protein content of 11%, an intermediate gelatinization temperature and gel consistency, and a gel hardness (~3 N for a Rapid Viscosity Analyzer pasting) and moderate retrogradation capacity (a setback viscosity of 30-100 RVU).

2.
Plant Dis ; 99(2): 284, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30699594

RESUMO

Peanut (Arachis hypogaea) is one of the most important oil crops and food legumes worldwide. China sows approximately 3.5 million hectares each year and produces 40% of the world's peanuts. Fungal diseases are among the main biotic stresses affecting peanut production. Root rot is a serious disease caused by several fungi. Pythium spp., Fusarium spp., and Rhizopus spp. are some of the root rot fungi that have been reported in China. In 2012 and 2013, root rot symptoms were observed in several fields in Laixi District, Qingdao City, Shandong Province, China. The first symptoms appeared in July. Initial symptoms of the disease were brown spots on the stem base and root. Affected plants were stunted, with leaf chlorosis, reduced growth, or sudden wilting. As disease progressed, the infected tissues showed brown discoloration and rot, and abundant dark brown and black powdery spores were visible on the surfaces of affected parts. Eventually, affected plants collapsed and died. To isolate the causal organism, roots and stems were cut into sections, which were surface-disinfected with 70% ethanol solution (v/v) for 20 s, soaked in 0.1% mercuric chloride solution for 50 s, rinsed with sterilized water three times, dried, placed on Czapek's Dox agar supplemented with chloramphenicol (100 µg/ml), and incubated at 28°C for 7 days. Fungal colonies were white initially and then covered with a dense layer of dark brown or black conidial heads. The conidial head was radiate; vesicles were nearly spherical and covered with irregular metulae and phialides. Conidia were globose or subglobose (3.0 to 5.5 µm in diameter), dark brown to black, with rough cell walls. Total genomic DNA was extracted from mycelia using the EasyPure Genomic DNA Kit (TransGEN, Beijing, China). The rDNA-ITS region was amplified using PCR with the universal fungal primers ITS1 and ITS4 (2). The purified products were separately sequenced in both directions using the same primer pair. The sequences (GenBank Accession No. KJ848716) obtained were 99% similar to the ITS sequence of isolates of Aspergillus niger. This, together with the morphological characters (1) described above, suggested that the microorganism we had isolated was A. niger. Koch's postulates were completed in the laboratory by inoculating peanut. Thirty Huayu20 peanut seeds were placed in a 500-ml sterile pot with 300 g of autoclaved soil. Twenty days after seedling emergence, 15 peanut plants were wounded with a needle and inoculated with 5 ml of conidia suspension (106 ml-1). The same number of peanuts were similarly wounded and inoculated with 5 ml of sterile distilled water to serve as controls in the same pot. All peanuts were kept in a randomized complete block design at 30°C under a 12-h photoperiod. After 7 days, disease symptoms similar to those observed in the field appeared in all inoculated but not in non-inoculated peanuts. The tests were repeated three times in the greenhouse. Koch's postulates were satisfied after re-isolating the A. niger from inoculated peanuts using the method described above. To our knowledge, this is the first report of A. niger causing root rot in peanut in China. References: (1) M. A. Klich. Page 12 in: Identification of Common Aspergillus Species. Centraalbureau voor Schimmelcultures, Utrecht, The Netherlands, 2002. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.

3.
Phytopathology ; 103(9): 949-59, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23550972

RESUMO

To study the population genetic structure and forces driving the evolution of Wheat yellow mosaic virus (WYMV), the nucleotide sequences encoding the coat protein (CP) (297 sequences) or the genome-linked virion protein (VPg) (87 sequences) were determined from wheat plants growing at 11 different locations distributed in five provinces in China. There were close phylogenetic relationships between all sequences but clustering on the phylogenetic trees was congruent with their provenance, suggesting an origin-dependent population genetic structure. There were low levels of genetic diversity, ranging from 0.00035 ± 0.00019 to 0.01536 ± 0.00043 (CP), and 0.00086 ± 0.00039 to 0.00573 ± 0.00111 (VPg), indicating genetic stability or recent emergence of WYMV in China. The results may suggest that founder effects play a role in shaping the genetic structure of WYMV. Between-population diversity was consistently higher than within-population diversity, suggesting limited gene flow between subpopulations (average FST 0.6241 for the CP and 0.7981 for the VPg). Consistent amino acid substitutions correlated with the provenance of the sequences were observed at nine positions in the CP (but none in the VPg), indicating an advanced stage in population structuring. Strong negative (purifying) selection was implicated on both the CP and VPg but positive selection on a few codons in the CP, indicating an ongoing molecular adaptation.


Assuntos
Efeito Fundador , Estruturas Genéticas , Variação Genética , Genética Populacional , Potyviridae/genética , Seleção Genética , Sequência de Bases , Proteínas do Capsídeo/genética , China , Evolução Molecular , Genoma Viral/genética , Geografia , Filogenia , Doenças das Plantas/virologia , Potyviridae/isolamento & purificação , Potyviridae/patogenicidade , Potyviridae/fisiologia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Triticum/virologia , Proteínas Virais/genética
4.
Plant Dis ; 97(4): 561, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30722239

RESUMO

Coleus blumei, which was found originally in Indonesia, is an ornamental plant grown worldwide. It can be infected by several viroids of the genus Coleviroid, family Pospiviroidae. Six main viroids that infect coleus have been reported: Coleus blumei viroid 1 through 6 (CbVd-1 ~ CbVd-6). Although CbVd-1 was first reported in a commercial coleus in Brazil in 1989 (1), and then in Germany, Japan, Canada, Korea, China, and India, CbVd-5 was reported only in China in 2009 (2). Symptoms caused by CbVd-5 varied depending on different cultivars, and in case of an unknown cultivar of "Red with dark green edge," are very clear albino symptoms. From 2010 to 2011, 60 and 3 leaf samples of coleus were collected from Hyderabad, India, and Java, Indonesia, respectively, and subjected to low molecular weight RNA extraction according to Li et al. (3). The results of dot-blot hybridization using CbVd-5 cRNA probes and RT-PCR using CbVd-5 specific primers (CbVd-5-PF: 5'-TGACTAGAACAGTAGTAAAG-3' / CbVd-5-PR: 5'-AATTGAGGTCAAACCTCTTT-3') demonstrated that 28 out of the 60 samples from India and all three samples from Indonesia were positive for CbVd-5. The resulting RT-PCR fragments from one sample selected randomly from each country were cloned into the pMD18-T vector (Takara) and transformed into E. coli DH5α competent cells. Five positive clones of each sample were sequenced. The result of sequence analysis revealed that the similarities of CbVd-5 between the sequences we obtained and the reference sequence (GenBank Accession No. NC003683) were 97.8 to 100%. Bioassay using nine viroid-free coleus plants from three cultivars (three from each cultivar), inoculated with CbVd-5 infectious clones by stem slashing, demonstrated that CbVd-5 could induce albino symptom on the leaves of the unknown cultivar "Red with dark green edge" 2 months after inoculation. To our knowledge, this is the first report of CbVd-5 from India and Indonesia, and the second report of CbVd-5 in the world. Considering the effect of CbVd-5 on the appearance of coleus and its recombination ability, a certification program may be needed to control the spread of this viroid. References: (1) M. E. N. Fonseca et al. Fitopatol. Bras. 14:94, 1989. (2) W. Y. Hou et al. Arch. Virol. 154:315, 2009. (3) S. F. Li et al. Ann. Phytopathol. Soc. Jpn. 61:381, 1995.

5.
Plant Dis ; 93(7): 764, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30764367

RESUMO

Natural occurrence of Sweet potato leaf curl virus (SPLCV) has been reported in Ipomoea batatas (sweet potato, Convolvulaceae) or I. indica (Convolvulaceae) in several countries including the United States, Sicily, and China (1-3). In September of 2007, while collecting samples showing begomovirus-like symptoms in the Chinese province of Fujian, we observed tall morningglory (I. purpurea (L.) Roth, also known as Pharbitis purpurea (L.) Voigt), plants with slightly yellow mosaic and crinkled leaves. Total DNA was extracted from leaves of these plants and tested by rolling circle amplification (4). Amplification products were digested by the restriction enzyme BamHI for 30 min. Restriction products (2.8 kb) were then cloned into pMD18T vector (Takara Biotechnology, China) and sequenced. Comparison of complete DNA sequences by Clustal V analysis revealed that these samples were infected by the same virus, and an isolate denoted F-p1 was selected for further sequence analysis. F-p1 was 2,828 nucleotides, with the typical genomic organization of begomoviral DNA-A (GenBank Accession No. FJ515896). F-p1 was compared with the DNA sequences available in the NCBI database using BLAST. The whole DNA sequence showed the highest nucleotide sequence identity (92.1%) with an isolate of SPLCV (GenBank Accession No. FJ176701) from Jiangsu Province of China. The result confirmed that the samples from the symptomatic tall morningglory were infected by SPLCV. To our knowledge, this is the first report of the natural occurrence of SPLCV in I. purpurea, a common weed species in China. References: (1). P. Lotrakul et al. Plant Dis. 82:1253, 1998. (2). R. W. Briddon et al. Plant Pathol. 55:286, 2006. (3) Y. S. Luan et al. Virus Genes 35:379, 2007. (4) D. Haible et al. J. Virol. Methods 135:9, 2006.

6.
Plant Dis ; 92(1): 177, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30786379

RESUMO

A leaf curling disease was observed on 7% of tobacco plants during December 2005 in research plots in the Cangshan District of Fuzhou, Fujian, China. Tobacco plants were infested with Bemisia tabaci, suggesting begomovirus etiology. To identify possible begomoviruses, total DNA was extracted from four symptomatic leaf samples (F1, F2, F3, and F4). The degenerate primers PA and PB were used to amplify part of the intergenic region and AV2 gene of DNA-A-like molecules (3). A 500-bp DNA fragment was amplified by PCR from all four samples. The PCR products were cloned and sequenced (GenBank Accession Nos. EF531601-EF531603 and EF527823). Alignment of the 500-bp sequences for the four isolates indicated that they shared 98.5 to 99.6% nt identity, suggesting that the plants were all infected by the same virus. Overlapping primers TV-Full-F (5'-GGATCCTCTTTTGAACGAGTTTCC-3') and TV-Full-R (5'-GGATCCCACATGTTTAAAATAATAC-3') were then designed to amplify the full-length DNA-A from sample F2. The sequence was 2,754 nucleotides long (GenBank Accession No. EF527823). A comparison with other begomoviruses indicated the F2 DNA-A had the highest nucleotide sequence identity (95.7%) with Ageratum yellow vein virus (AYVV; GenBank Accession No. X74516) from Singapore. To further test whether DNAß was associated with the four viral isolates, a universal DNAß primer pair (beta 01 and beta 02) was used (4). An amplicon of approximately 1.3 kb was obtained from all samples. The DNAß molecule from F2 was then cloned and sequenced. F2 DNAß was 1,345 nucleotides long (GenBank Accession No. EF527824), sharing the highest nucleotide sequence identity with the DNAß of Tomato leaf curl virus (97.2%) from Taiwan (GenBank Accession No. AJ542495) and AYVV (88.8%) from Singapore (GenBank Accession No. AJ252072). The disease agent was transmitted to Nicotiana tabacum, N. glutinosa, Ageratum conyzoides, Oxalis corymbosa, and Phyllanthus urinaria plants by whiteflies (B. tabaci) when field infected virus isolate F2 was used as inoculum. In N. tabacum and N. glutinosa plants, yellow vein symptoms were initially observed in young leaves. However, these symptoms disappeared later during infection and vein swelling and downward leaf curling symptoms in N. tabacum and vein swelling and upward leaf curling in N. glutinosa were observed. In A. conyzoides, O. corymbosa, and P. urinaria plants, typical yellow vein symptoms were observed. The presence of the virus and DNAß in symptomatic plants was verified by PCR with primer pairs TV-Full-F/TV-Full-R and beta 01/beta 02, respectively. The above sequence and whitefly transmission results confirmed that the tobacco samples were infected by AYVV. In China, Tobacco leaf curl Yunnan virus, Tobacco curly shoot virus, and Tomato yellow leaf curl China virus were reported to be associated with tobacco leaf curl disease (1,3). To our knowledge, this is the first report of AYVV infecting tobacco in China. A. conyzoides is a widely distributed weed in south China and AYVV was reported in A. conyzoides in Hainan Island, China (2). Therefore, this virus may pose a serious threat to tobacco production in south China. References: (1) Z. Li et al. Phytopathology 95:902, 2005. (2) Q. Xiong et al. Phytopathology 97:405, 2007. (3) X. Zhou et al. Arch. Virol. 146:1599, 2001. (4) X. Zhou et al. J. Gen. Virol. 84:237, 2003.

7.
Cancer Lett ; 418: 196-203, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29317253

RESUMO

Radiation therapy (RT) is one of the primary modalities for triple-negative breast cancer (TNBC) treatment. However, due to the pro-metastatic potential of radiation and the intrinsic radiation resistance of some tumors, many patients experience RT failure, which leads to cancer relapse and distant metastasis. This preclinical study evaluated the efficacy of the antagonist of the SDF-1 receptor CXCR4, AMD3100, as a radiosensitizer in TNBC models. The combined effect of ionizing radiation and AMD3100 was determined in vitro by surviving fraction, cell cycle distribution, Bax and Bcl-2 expression, and apoptosis assays in a TNBC cell line (MDA-MB-231). For in vivo studies, human xenograft athymic nude mice were used. Treatment of TNBC cells with AMD3100 significantly augmented cellular radiosensitivity. Radiosensitivity was enhanced specifically through increased Bax expression, reduced Bcl-2 expression, prolonged G2-M arrest, and increased apoptosis. Combined treatment with AMD3100 and irradiation also enhanced tumor growth delay, with an enhancement factor ranging from 1.5 to 1.8. These findings support the evaluation of antagonists of the SDF-1 receptor CXCR4, such as AMD3100, as potent radiosensitizers in TNBC.


Assuntos
Compostos Heterocíclicos/farmacologia , Radiação Ionizante , Receptores CXCR4/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/terapia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Benzilaminas , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Quimiorradioterapia , Ciclamos , Feminino , Humanos , Camundongos Nus , Receptores CXCR4/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
8.
Blood Cancer J ; 7(6): e567, 2017 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-28574487

RESUMO

Despite the heterogeneity of acute myeloid leukemia (AML), overexpression of the interleukin-3 receptor-α (CD123) on both the more differentiated leukemic blast and leukemic stem cells (LSCs) provides a therapeutic target for antibody treatment. Here we present data on the potential clinical activity of the monoclonal antibody CSL362, which binds to CD123 with high affinity. We first validated the expression of CD123 by 100% (52/52) of patient samples and the correlation of NPM1 and FLT3-ITD mutations with the high frequency of CD123 in AML. In vitro studies demonstrated that CSL362 potently induced antibody-dependent cell cytotoxicity (ADCC) of AML blasts including CD34+CD38-CD123+ LSCs by natural killer cells (NKs). Importantly, compared with healthy donor (HD) NKs, NKs drawn from AML patients in remission had a comparable ADCC activity against leukemic cells; of note, during remission, immature NKs were five times higher in AML patients than that in HDs. Significantly, we report a case where leukemic cells were resistant to autologous ADCC; however, the blasts were effectively lysed by CSL362 together with donor-derived NKs after allogeneic hematopoietic stem cell transplantation. These studies highlight CSL362 as a promising therapeutic option following chemotherapy and transplant so as to improve the outcome of AML patients.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/genética , Subunidade alfa de Receptor de Interleucina-3/metabolismo , Células Matadoras Naturais/imunologia , Leucemia Mieloide Aguda/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Leucemia Mieloide Aguda/patologia , Pessoa de Meia-Idade , Nucleofosmina , Indução de Remissão , Adulto Jovem
9.
Food Chem ; 217: 217-224, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27664629

RESUMO

The cadmium (Cd) and lead (Pb) content in both white and wholemeal flour milled from 110 leading rice cultivars was assessed. The white flour Cd content ranged from <0.0025 to 0.2530mg/kg (geometric mean (GM)=0.0150mg/kg), while its Pb content ranged from <0.0250 to 0.3830mg/kg (GM=0.0210mg/kg). The indica types took up higher amounts of Cd and Pb than did the japonica types. Although the heavy metal content of wholemeal flour tended to higher than that of white flour, nevertheless 84.5% (Cd) and 95.4% (Pb) of the entries were compliant with the national maximum allowable concentration of 0.2000mg/kg of each contaminant. An analysis of the Cd content in the white flour of three indica type cultivars grown in two consecutive years at two locations indicated that Cd content may be significantly affected by the conditions prevailing in the growing season.


Assuntos
Cádmio/análise , Grão Comestível/química , Chumbo/análise , Oryza/química , China , Culinária , Farinha/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Qualidade dos Alimentos , Reprodutibilidade dos Testes
10.
Br J Pharmacol ; 123(4): 599-604, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9517376

RESUMO

1. Whole cell and single channel recordings of ATP-sensitive K+ current (I(K,ATP)) were carried out in ventricular myocytes isolated from neonatal rat hearts. 2. (+/-)-Propranolol, a commonly used beta-blocker, inhibited the whole cell I(K,ATP) in a concentration-dependent manner with a half-maximal concentration (IC50) of 6.7 +/- 1.4 microM, whereas it blocked the inward rectifier K+ current (I(K,I)) only at much higher concentrations (IC50 = 102.4 +/- 20.2 microM). The inhibition was time- and voltage-independent. 3. In the outside-out patch configuration, (+/-)-propranolol inhibited I(K,ATP) (IC50 = 9.8 +/- 2.9 microM) by decreasing the open probability of the channel without inducing additional noise in the open-channel current or a decrease of single channel conductance. The single channel current of I(K,I) was also blocked by (+/-)-propranolol in the same way as I(K,ATP). 4. (+)-Propranolol, an optic isomer having no beta-blocking effect, inhibited I(K,ATP) (IC50 = 5.8 +/- 1.0 microM), whilst atenolol, a selective beta1-blocker had no effect. Neither GDPbetaS (1 mM) nor GTPgammaS (200 microM) included in the pipette solution modulated the inhibitory effect of (+/-)-propranolol. 5. We concluded that the inhibitory effect of (+/-)-propranolol was not via the beta-adrenergic signal transduction pathway, but by direct inhibition of I(K,ATP) channels.


Assuntos
Trifosfato de Adenosina/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Coração/efeitos dos fármacos , Bloqueadores dos Canais de Potássio , Propranolol/farmacologia , Envelhecimento/fisiologia , Animais , Animais Recém-Nascidos , Proteínas de Ligação ao GTP/fisiologia , Coração/fisiologia , Técnicas In Vitro , Canais de Potássio/fisiologia , Ratos , Receptores Adrenérgicos beta/fisiologia
11.
Jpn J Physiol ; 44 Suppl 2: S219-26, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7752528

RESUMO

The inhibitory pathway of cardiac cAMP-dependent protein kinase regulated Cl- conductance was investigated using the whole-cell configuration of patch-clamp techniques in single guinea pig ventricular myocytes. Pertussis toxin-sensitive G proteins (Gi), mediating the signal transductions between muscarinic receptors and adenylate cyclase, have a substantial tonic activity even in the absence of muscarinic receptor modulators. Muscarinic agonists or antagonists (like atropine) either increase or decrease this basal activity of Gi by altering the proportion of active and inactive forms of the receptors. Similar to L-type Ca-channel currents, the Cl- conductance showed a transient over-recovery upon cessation of brief muscarinic receptor stimulation by carbachol (CCh) (rebound). Atropine alone enhanced the Cl- conductance elicited by low concentrations of Iso (reverse agonist). After washout of atropine, the over-suppression of the conductance was observed as a mirror image of CCh-induced rebound (reverse rebound). Both types of rebound became prominent when cell dialysis with pipette solutions containing 100 microM GTP was minimized with high-resistance pipettes. Endogenous GTP is therefore an intracellular modulator, and not simply a mediator, of Gi-dependent signal transduction.


Assuntos
Toxina Adenilato Ciclase , Canais de Cloreto/fisiologia , Coração/efeitos dos fármacos , Toxina Pertussis , Fatores de Virulência de Bordetella/toxicidade , Animais , Colforsina/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/farmacologia , Relação Dose-Resposta a Droga , Proteínas de Ligação ao GTP , Cobaias , Isoproterenol/farmacologia , Técnicas de Patch-Clamp
12.
Jpn J Physiol ; 44 Suppl 2: S227-30, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7752529

RESUMO

The effects of endothelin-1 (ET-1) on whole-cell cardiac PKA-dependent Cl- currents (ICl) were investigated using patch clamp techniques. ET-1 inhibited the isoproterenol-induced ICl with a half-maximally effective concentration of approximately 1 nM. ET-1 also inhibited the forskolin-induced current in a similar concentration range. The effects of ET-1 were abolished by pre-treatment of the cells with pertussis toxin. Since ET-1 was ineffective at inhibiting the ICl induced by internal dialysis with cyclic AMP, it is unlikely that the Gi-protein had a direct effect on channel gating or phosphorylation of the channel by PKA. It is concluded that ET-1 inhibited the cardiac PKA-dependent ICl by attenuating activation of adenylate cyclase and that this effect was mediated by a pertussis toxin-sensitive G-protein, presumably Gi.


Assuntos
Canais de Cloreto/efeitos dos fármacos , Endotelinas/farmacologia , Coração/efeitos dos fármacos , Toxina Adenilato Ciclase , Animais , Proteínas Quinases Dependentes de AMP Cíclico/farmacologia , Potenciais Evocados/efeitos dos fármacos , Isoproterenol/farmacologia , Toxina Pertussis , Fatores de Virulência de Bordetella/toxicidade
13.
Jpn J Physiol ; 46(6): 491-5, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9087860

RESUMO

We obtained cDNA encoding KIR6.2 channel from the rat brain cDNA library. The reconstituted K+ channel with KIR6.2 and SUR1 genes retained properties similar to those reported in the native ATP-sensitive K+ channel including run-down and recovery of channel activity. When KIR6.2 was co-expressed with CFTR or MDR1, no K+ channel activity was recorded.


Assuntos
Encéfalo/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização , Canais de Potássio/genética , Sequência de Aminoácidos , Animais , Células COS , Clonagem Molecular , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , DNA Complementar/genética , Expressão Gênica , Dados de Sequência Molecular , Canais de Potássio/metabolismo , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transfecção
14.
Methods Find Exp Clin Pharmacol ; 12(6): 419-24, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2087141

RESUMO

Monophasic action potential (MAP) recording with contact electrode has been applied to study triggered activities of the heart. Intracellular evidence in vivo, however, of the MAP technique is lacking. In the present study, transmembrane action potential (TAP) recorded with floating glass microelectrode was compared with MAP in 18 cat hearts in vivo. The results were as follows. 1) In control conditions, the MAP duration at 50 and 90% repolarization was similar to that of TAP without any significant difference. 2) 10 sec after CsCl (0.5 mM/kg, i.v.), early afterdepolarization (EAD) appeared in the middle-late period of phase 3 both in the MAP and TAP; 30 sec after CsCl, the amplitude of MAP-EAD was 3.4 +/- 1.3 mV and that of TAP-EAD was 25.6 +/- 9.3 mV. Delayed afterdepolarization (DAD) was also induced by CsCl in phase 4 of the MAP and TAP simultaneously. The amplitude of MAP-DAD was 3.3 +/- 0.6 mV and that of TAP-DAD was 13.0 +/- 5.3 mV. 3) Triggered arrhythmias, including premature ventricular beat and tachycardia, induced by CsCl repeated injection were observed in the MAP and TAP recording synchronously. The present study not only provides an intracellular and direct evidence in vivo but also suggests that the contact electrode MAP technique could be applied to study triggered activities of the heart in vivo.


Assuntos
Potenciais de Ação/fisiologia , Cloretos , Coração/fisiologia , Potenciais da Membrana/fisiologia , Animais , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/fisiopatologia , Gatos , Césio/administração & dosagem , Césio/farmacologia , Injeções Intravenosas , Líquido Intracelular/fisiologia , Membranas/fisiologia , Miocárdio/ultraestrutura
15.
Artigo em Inglês | MEDLINE | ID: mdl-8479243

RESUMO

The effects of Chinese medicine, alcoholized rhubarb, on cardiac electrophysiology and contractile force were studied by using monophasic action potential (MAP) techniques with an improved pressure-electrical transducer epicardial electrode and/or an endocardial pressure-contact electrode catheter in 27 feline hearts in vivo. The results of the experiments were as follows: 1) Alcoholized rhubarb solution (1.5 g/kg) caused a greater increase in the MAP amplitude (from 18.8 +/- 0.62 mV to 26.7 +/- 3.87 mV, p < 0.01), in the MAP maximum rate of rise of phase 0 (from 1.7 +/- 0.13 V/sec to 2.6 +/- 0.43, p < 0.01), and in the MAP duration at 50% and 90% repolarization (from 194.3 +/- 14.00 msec to 216.3 +/- 6.30 msec and from 238.8 +/- 21.41 msec to 280.5 +/- 14.68 msec, respectively, p < 0.01), and a decrease in the heart rate (from 130.8 +/- 12.10 bpm to 110.8 +/- 10.35 bpm, p < 0.01) in the epicardial monophasic action potentials after rhubarb solution administration for 1 min. 2) The ventricular contractile force of the feline heart in vivo was also significantly increased (11.1 +/- 0.52 g to 14.0 +/- 1.41 g, p < 0.01) by rhubarb solution. 3) A dose-dependent relation of alcoholized rhubarb solution was found and indicated that lower doses (1.0-1.5 g/kg) had an excitatory effect, while a higher dose (2.0 g/kg) had inhibitory or toxic effects on the intact feline heart. The present study provides evidence that Chinese rhubarb solution has electrophysiological effects on the feline heart in vivo.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Coração/efeitos dos fármacos , Plantas Medicinais , Rheum , Potenciais de Ação/efeitos dos fármacos , Animais , Gatos , Relação Dose-Resposta a Droga , Eletrocardiografia/efeitos dos fármacos , Etanol , Feminino , Frequência Cardíaca/efeitos dos fármacos , Masculino , Contração Miocárdica/efeitos dos fármacos
16.
Methods Find Exp Clin Pharmacol ; 10(7): 475-6, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3419251

RESUMO

The pharmacological effects of resibufogenin (RGB), an effective cardiotonic obtained from a famous traditional Chinese medicine, on the electrical activity of the rabbit heart (n = 12) in situ were studied by using a new technique of recording monophasic action potential (MAP). RBG (0.3 mg/kg IV) induced DAD in 3/12 animals. DAD appeared within the first 0.5 to 1 min after RBG and lasted about 20-30 min. The position of DAD was in the end of phase 3 of MAP. The DADs of rabbit epicardium showed a transient, regular and phasic depolarization process. The triggered arrhythmias were not recorded in these experiments, as amplitudes of DAD were lower and did not reach the threshold. The results indicate that DADs are induced by RBG at first time in situ in rabbits. The characteristics of DAD were similar to those previously described in single cardiac fibers in vitro.


Assuntos
Bufanolídeos/farmacologia , Cardiotônicos/farmacologia , Coração/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Animais , Arritmias Cardíacas/induzido quimicamente , Relação Dose-Resposta a Droga , Feminino , Injeções Intravenosas , Masculino , Coelhos
17.
Sheng Li Xue Bao ; 43(3): 257-64, 1991 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-1788560

RESUMO

CsCl triggered activities in cat heart in vivo were studied by using floating microelectrode and contact electrode to record transmembrane and monophasic action potentials (TAP and MAP). Ten seconds after CsCl (0.5 m mol/kg, i.v.), early after depolarization (EAD) appeared in the middle-later period of phase 3 in both TAP and MAP. Thirty seconds after CsCl, the amplitude of TAP-EAD was 25.6 +/- 9.3 mV and that of MAP-EAD was 3.4 +/- 1.3 mV. The potential changes of the EADs could be divided into three kinds, i.e. the "tail", the "plateau" and "peak" types. Delayed after depolarization (DADs) could also be induced by CsCl in the phase 4 of the TAP and MAP in two cats. The amplitudes of TAP-DAD and MAP-DAD were 13.0 +/- 5.3 mV and 3.3 +/- 0.6 mV respectively. The types of the afterdepolarizations in MAP were very similar to those in TAP. The ventricular extrasystole and/or tachycardias could be induced by repeated injections of CsCl. According to the occurrence of after depolarization (AD) and the relationship between the coupling interval of the AD and that of the ventricular beat, two kinds of generation of arrhythmias were suggested, i.e. one triggered by AD of the myocardium under the electrode and the other induced by AD originating from the other sites of the myocardium.


Assuntos
Arritmias Cardíacas/fisiopatologia , Cloretos , Coração/fisiopatologia , Potenciais de Ação , Animais , Arritmias Cardíacas/induzido quimicamente , Gatos , Césio , Feminino , Masculino
18.
Zhongguo Zhong Yao Za Zhi ; 25(11): 654-6, 2000 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-12525068

RESUMO

OBJECTIVE: To establish a TLC identification method for Xuanshen(Radix Scrophulariae). METHOD: Using TLC with harpagoside and harpagide as reference substances. RESULT: A TLC identification method of Xuanshen has been established. The specificity of the method has been proved by a comparative detection of Xuanshen from different habitats and several crude drugs which are easily confused with Xuanshen. CONCLUSION: The method is simple, accurate and reliable.


Assuntos
Medicamentos de Ervas Chinesas , Glicosídeos/análise , Piranos/análise , Scrophularia , Cromatografia em Camada Fina , Contaminação de Medicamentos , Medicamentos de Ervas Chinesas/química , Glicosídeos Iridoides , Scrophularia/química
19.
Food Chem ; 142: 92-100, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24001817

RESUMO

Near-infrared reflectance spectroscopy (NIRS) has been used to predict the cooking quality parameters of rice, such as the protein (PC) and amylose content (AC). Using brown and milled flours from 519 rice samples representing a wide range of grain qualities, this study was to compare the calibration models generated by different mathematical, preprocessing treatments, and combinations of different regression algorithm. A modified partial least squares model (MPLS) with the mathematic treatment "2, 8, 8, 2" (2nd order derivative computed based on 8 data points, and 8 and 2 data points in the 1st and 2nd smoothing, respectively) and inverse multiplicative scattering correction preprocessing treatment was identified as the best model for simultaneously measurement of PC and AC in brown flours. MPLS/"2, 8, 8, 2"/detrend preprocessing was identified as the best model for milled flours. The results indicated that NIRS could be useful in estimation of PC and AC of breeding lines in early generations of the breeding programs, and for the purposes of quality control in the food industry.


Assuntos
Amilose/química , Farinha/análise , Oryza/química , Proteínas de Plantas/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos
20.
Curr Mol Med ; 14(1): 174-84, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24256053

RESUMO

Triple negative breast cancer is known for its visceral metastasis. We have found that CXCR4 is overexpressed in triple negative breast cancer and is associated with visceral metastasis. We further investigated whether CXCR4 is a prognostic factor affecting survival following visceral metastasis in breast cancer patients. Our results indicate that increased CXCR4 expression among breast cancer patients with visceral metastasis was positively correlated with poor overall survival (P<0.001). Silencing of CXCR4 was associated with a decrease in the tumorigenic properties of MDA-MB-231 breast cancer cells, caused reversion of EMT and suppression of MMP-9, increased apoptosis, and caused a reduced incidence of tumor lung metastasis in mice. These results are indicative of CXCR4 having a predictive role in patients with visceral metastasis and indicate that shRNA knock down of CXCR4 might be a novel therapeutic strategy to prevent breast cancer metastasis when CXCR4 is overexpressed.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Expressão Gênica , Receptores CXCR4/genética , Adulto , Idoso , Animais , Apoptose/genética , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/genética , Feminino , Inativação Gênica , Humanos , Neoplasias Pulmonares/secundário , Camundongos , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Receptores CXCR4/metabolismo , Fatores de Risco , Carga Tumoral/genética , Ensaio Tumoral de Célula-Tronco , Ensaios Antitumorais Modelo de Xenoenxerto
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