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1.
Rheumatology (Oxford) ; 47(4): 454-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18316335

RESUMO

OBJECTIVE: Animal models are useful tools to study various aspects of human diseases. Bleomycin (BLM)-induced scleroderma mouse has been widely investigated as an animal model of scleroderma. Repeated injections of BLM, either daily or every other day, for 3-4 weeks are required to induce scleroderma in mice. Poly(L-lactic acid) (PLA) is a biodegradable, biocompatible and bioabsorbable device that has been widely investigated for controlled drug release. In this study, we fabricated BLM-containing PLA microspheres and subcutaneously injected them into C3H mice for only one time. METHODS: Treated skins were harvested at days 7 and 21. Then, histological examination and collagen content measurement assay were performed. The mRNA expression of alpha1(I) collagen (COL1A1), monocyte chemoattractant protein-1 (MCP-1), TGF-beta(1) and connective tissue growth factor (CTGF) were quantified by real-time PCR. RESULTS: Dermal fibrosis was histologically observed at day 7 after injection and remained present at day 21. Tissue responses against BLM-PLA microspheres alone were mild. Soluble collagen content and expression level of alpha1(I) collagen mRNA were significantly elevated at day 21. Expression levels of MCP-1 mRNA and TGF-beta(1) mRNA at day 7 and CTGF mRNA at day 21 were also elevated. CONCLUSION: The present study demonstrated for the first time that one-time injection of BLM-PLA microspheres can induce dermal fibrosis in C3H mice. BLM-PLA microspheres thus offer a labour-saving, simple and powerful tool to establish an animal model of BLM-induced dermal fibrosis.


Assuntos
Bleomicina/administração & dosagem , Modelos Animais de Doenças , Escleroderma Sistêmico/induzido quimicamente , Pele/patologia , Animais , Bleomicina/toxicidade , Quimiocina CCL2/biossíntese , Quimiocina CCL2/genética , Colágeno/análise , Colágeno Tipo I/biossíntese , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Fator de Crescimento do Tecido Conjuntivo , Preparações de Ação Retardada , Feminino , Fibrose/induzido quimicamente , Fibrose/metabolismo , Expressão Gênica , Proteínas Imediatamente Precoces/biossíntese , Proteínas Imediatamente Precoces/genética , Injeções Subcutâneas , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular/genética , Ácido Láctico , Camundongos , Camundongos Endogâmicos C3H , Microesferas , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/genética , Escleroderma Sistêmico/metabolismo , Escleroderma Sistêmico/patologia , Pele/metabolismo , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/genética
2.
Int J Dermatol ; 45(3): 302-5, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16533235

RESUMO

We describe two cases of a 3-year-old Japanese boy and his 1-year-old sister presenting recessive dystrophic epidermolysis bullosa; a relatively mild phenotype. Blistering and scarring were limited to the acral region, and some fingernails and toenails were lost. PCR-RFLP and DNA sequencing analyses revealed compound heterozygotes for a splice-site mutation (6573 +1GtoC) and a nonsense mutation (E2857X) in the type VII collagen gene (COL7A1). Both mutations caused a premature termination codon (PTC). The mutation E2857X was located behind the candidate cleavage site within the NC-2 domain required for the assembly of anchoring fibrils. This PTC position may explain their mild phenotype.


Assuntos
Colágeno Tipo VII/genética , Epidermólise Bolhosa Distrófica/genética , Pré-Escolar , Feminino , Heterozigoto , Humanos , Lactente , Japão , Masculino , Mutação , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Irmãos
3.
Dermatology ; 208(3): 217-20, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15118370

RESUMO

We describe the case of a 59-year-old Japanese woman presenting with generalized lentigines without systemic anomalies. She had a medical history of gastrointestinal stromal tumors (GISTs), in which gain-of-function mutations of the c-kit gene had recently been found. We detected a point mutation at codon 557 in exon 11 of leukocyte DNA from the patient. The stem cell factor-type III receptor tyrosine kinase pathway plays important roles in the regulation of melanocyte proliferation and differentiation. We speculate that the generalized lentigines of the patient may be caused by melanocyte proliferation due to the c-kit gene mutation.


Assuntos
Neoplasias Gastrointestinais/genética , Síndrome LEOPARD/genética , Mutação Puntual , Proteínas Proto-Oncogênicas c-kit/genética , Células Estromais/patologia , Códon , Éxons , Feminino , Neoplasias Gastrointestinais/patologia , Humanos , Pessoa de Meia-Idade
4.
J Biochem Biophys Methods ; 49(1-3): 683-703, 2001 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-11694311

RESUMO

This review describes the surface-affinity chromatography of human peripheral blood cells on polyethylene glycol (PEG) and polypropylene glycol (PPG) chemically bonded columns. The affinity of surface blood cells to bonded PEG and PPG stationary phases is apparently selective, and granulocytes and lymphocytes are more strongly retained on the column than erythrocytes and platelets. The retention factors of granulocytes and lymphocytes increased with increase in the hydrophobicities (Delta log K values) of PPG-agarose column packing beads. Hydrophobic interactions contributed to the retention of the blood cells on the PPG-bonded agarose columns.


Assuntos
Citaferese/métodos , Eritrócitos/citologia , Cromatografia de Afinidade/métodos , Granulócitos/citologia , Humanos , Linfócitos/citologia , Polietilenoglicóis , Propilenoglicol , Propriedades de Superfície
5.
Photochem Photobiol ; 74(3): 407-11, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11594053

RESUMO

Sunlight was found to strongly induce the formation of N epsilon-(carboxymethyl)lysine (CML) from glycated polylysine in the presence of Fe(III) ion. The initial step of this Fe(III)-catalyzed CML formation was noted to be similar to that of blueprint photography as was confirmed by the production of Turnbull's blue in sunlight-exposed glycated human serum albumin ferricyanide solution in the presence of Fe(III). Based on this, photoinduced oxidative C-C bond cleavage of the Amadori compound was assumed to be initiated by photochemical single electron transfer front ligand to Fe(III) in the Fe(III)-Amadori compound complex affording the Fe(II)-Amadori compound radical intermediate, which eventually yields either CML or active oxygen species. CML is thus a useful oxidative stress marker. The mechanism proposed here would explain the high accumulation of CML in lens protein and skin actinic elastosis.


Assuntos
Lisina/análogos & derivados , Lisina/efeitos da radiação , Luz Solar/efeitos adversos , Produtos Finais de Glicação Avançada , Glicosilação , Humanos , Técnicas In Vitro , Ferro/química , Ferro/efeitos da radiação , Espectroscopia de Ressonância Magnética , Fotoquímica , Polilisina/química , Polilisina/efeitos da radiação , Albumina Sérica/efeitos da radiação , Albumina Sérica Glicada
6.
J Chromatogr A ; 886(1-2): 65-73, 2000 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-10950276

RESUMO

Apple procyanidins were separated by high-speed counter-current chromatography using a type-J multilayer coil planet centrifuge. Several two-phase solvent systems with a wide range of hydrophobicities from a non-polar hexane system to polar n-butanol systems were evaluated their performance in terms of the partition coefficient and the retention of the phase. The best separation of procyanidins B and C was achieved with a two-phase solvent system composed of n-butanol-methyl tert.-butyl ether-acetonitrile-0.1% trifluoroacetic acid (2:4:3:8) using the lower phase as a mobile at a flow-rate of 1.0 ml/min.


Assuntos
Biflavonoides , Catequina/isolamento & purificação , Cromatografia/métodos , Frutas/química , Proantocianidinas
7.
J Chromatogr B Biomed Sci Appl ; 722(1-2): 71-88, 1999 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-10068134

RESUMO

Column packings with chemically bonded polyethylene glycol (PEG) and polypropylene glycol (PPG) were prepared and the separation of human peripheral blood cells by an aqueous polymeric two phase system could be performed in a partition chromatography. In this chromatographic system, the interaction of blood cells with bonded PEG, PPG stationary phases is apparently selective, and granulocytes and lymphocytes are more strongly retained on the column than erythrocytes and platelets. The hydrophobic interactions between the hydrophobic region on the cell surface membrane and the bonded PEG, PPG phases is probably the main factor affecting the retention of lymphocytes and granulocytes. The selective separation of human peripheral platelets, granulocytes and lymphocytes was investigated using another type of column packing bonded with methoxyethoxymethyl (MEM) groups. The isolation of platelets and lymphocytes from human leukocyte-rich plasma was performed with a MEM-Sephadex column and elution with 0.27 M sucrose solution. Platelets could be selectively collected from the same column by elution with 0.31 M methyl-alpha-D-mannoside at the high recovery of 100%.


Assuntos
Células Sanguíneas , Separação Celular/métodos , Cromatografia de Afinidade/métodos , Humanos , Ponto Isoelétrico
8.
J Chromatogr B Biomed Sci Appl ; 709(2): 301-5, 1998 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-9657228

RESUMO

Proteins present in chicken egg white are separated by counter-current chromatography (CCC) in one step using a cross-axis coil planet centrifuge (X-axis CPC). The separation was performed with an aqueous polymer two-phase system composed of 16% (w/w) poly(ethylene glycol) 1000 and 12.5% (w/w) dibasic potassium phosphate by eluting the lower phase at a flow-rate of 1.0 ml/min. From about 20 g of the crude egg white solution, lysozyme, ovalbumin, and ovotransferrin were resolved within 5.5 h. Each component was identified by 12% SDS gel electrophoresis with Coomassie brilliant blue staining.


Assuntos
Conalbumina/isolamento & purificação , Clara de Ovo , Muramidase/isolamento & purificação , Ovalbumina/isolamento & purificação , Animais , Soluções Tampão , Centrifugação , Galinhas , Cromatografia/instrumentação , Cromatografia/métodos , Eletroforese em Gel de Poliacrilamida , Fosfatos , Polietilenoglicóis , Compostos de Potássio
10.
J Chromatogr B Biomed Sci Appl ; 699(1-2): 419-37, 1997 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-9392386

RESUMO

This review describes two chromatographic techniques for the separation of three main classes of lipoproteins (HDLs, LDLs and VLDLs) from human serum: hydroxyapatite chromatography and counter-current chromatography. The HDLs, LDLs and VLDLs were purified by the combined use of the two chromatographic techniques without prior ultracentrifugation.


Assuntos
Cromatografia Líquida/métodos , Eletroforese/métodos , Lipoproteínas/isolamento & purificação , Humanos , Lipoproteínas/sangue , Lipoproteínas/classificação
11.
J Chromatogr B Biomed Sci Appl ; 696(1): 25-31, 1997 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9300905

RESUMO

To test the utility of counter-current chromatography in purifying proteins, lactic acid dehydrogenase (LDH) was extracted from a crude bovine heart filtrate using a cross-axis coil planet centrifuge. The purification was performed with several polymer phase systems composed of 16% (w/w) poly(ethylene glycol) (PEG) 1000-12.5% (w/w) potassium phosphate buffers and 4.4% (w/w) PEG 8000-7.0 (w/w) dextran T500 at pH values ranging from 6.5 to 11.0. The best purification was achieved using PEG 1000-potassium phosphate buffer system at pH 7.3 by eluting the upper phase at 1.0 ml/min. Fractions were analyzed by LDH enzymatic activity and sodium dodecyl sulfate slab gel electrophoresis (SDS-PAGE). The LDH was purified directly from bovine heart crude extract within 3 h.


Assuntos
Cromatografia Líquida/métodos , L-Lactato Desidrogenase/isolamento & purificação , Miocárdio/enzimologia , Extratos de Tecidos/química , Animais , Bovinos , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , L-Lactato Desidrogenase/metabolismo
12.
J Chromatogr B Biomed Appl ; 666(2): 233-9, 1995 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-7633599

RESUMO

Selective separation of human peripheral platelets, granulocytes and lymphocytes was investigated by column liquid chromatography using methoxyethoxymethyl (MEM) bonded-phase columns (25 x 0.9 cm I.D.). Isotonic solutions containing mono- and disaccharides, methyl-alpha-D-pyranosides and a physiological saline at pH 7.4 were used as the mobile phase. Granulocytes and lymphocytes were separated on the MEM-Cellulofine GH-25 column by elution with 0.3 M D-mannose solution. The isolation of platelets and lymphocytes from human leukocyte-rich plasma was performed with a MEM-Sephadex G25 column and elution with 0.27 M sucrose solution. On the same column platelets could also be collected selectively by elution with 0.31 M methyl-alpha-D-mannoside at the high recovery of 100%. The isolated cells were viable for more than 90%.


Assuntos
Plaquetas/citologia , Separação Celular/métodos , Cromatografia de Afinidade/métodos , Granulócitos/citologia , Linfócitos/citologia , Cromatografia por Troca Iônica , Humanos
13.
J Chromatogr B Biomed Appl ; 664(2): 295-301, 1995 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-7780580

RESUMO

High-density, low-density and very-low-density lipoproteins (HDLs, LDLs and VLDLs) were purified from human serum by the combined use of counter-current chromatography (CCC) and hydroxyapatite chromatography. Polymer-phase CCC of human serum using the cross-axis coil planet centrifuge yielded two lipoprotein fractions, one containing HDLs and LDLs and the other VLDLs and serum proteins. Each fraction was concentrated and subjected to hydroxyapatite chromatography to obtain three lipoprotein fractions, all free from serum proteins. Each lipoprotein was confirmed by agarose gel electrophoresis.


Assuntos
Lipoproteínas/isolamento & purificação , Cromatografia , Cromatografia em Agarose , Eletroforese em Gel de Poliacrilamida , Humanos , Hidroxiapatitas , Lipoproteínas/sangue , Masculino , Fosfatos , Polietilenoglicóis , Compostos de Potássio
14.
J Chromatogr ; 625(2): 177-81, 1992 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-1474121

RESUMO

Counter-current chromatography (CCC) of the bromoacetylation product of 3,3',5-triiodo-L-thyronine (T3) produced an unusually sharp peak for the desired product, N-bromoacetyl T3 (BrAcT3). A series of experiments revealed that bromoacetic acid, probably present as a side reaction product in the sample solution, was responsible. This compound repressed the ionization of the carboxyl group of BrAcT3 forcing it into the less polar stationary phase until the bromoacetic acid had eluted completely from the apparatus. At this point, the sudden increase of pH and consequent ionization of the BrAcT3 allowed the ammonium salt of the latter to enter the more polar moving phase where it eluted rapidly from the column as a sharp peak. The same phenomenon was observed in the CCC fractionation of a series of indole auxins where addition of trifluoroacetic acid to the sample caused peak sharpening by the same process. The phenomenon recalls pH gradient elution and isoelectric focussing except that the substance responsible for the pH range here is added along with the sample in one bolus forming a sharp pH gradient at its trailing edge. As with gradient elution, the technique is of practical interest since it permits collection of the eluting compounds with increased detectability in fewer fractions. The technique can also enhance separation of compounds whose partition coefficients differ with a change in pH.


Assuntos
Acetatos/análise , Bromo/química , Cromatografia Líquida/métodos , Acetilação , Concentração de Íons de Hidrogênio , Espectrofotometria Ultravioleta , Tri-Iodotironina/análogos & derivados , Tri-Iodotironina/química
15.
J Chromatogr ; 607(1): 47-53, 1992 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-1332984

RESUMO

A synthetically prepared mixture of brominated 4,5,6,7-tetrachlorofloresceins was separated by a combination of preparative reversed-phase high-performance liquid chromatography and high-speed counter-current chromatography. Two new lower-brominated subsidiary colors of D&C Red Nos. 27 and 28 (phloxine B), 4',5'-dibromo-4, 5,6,7-tetrachlorofluorescein and 2',4',5'-tribromo-4,5,6, 7-tetrachlorofluorescein, were isolated and characterized by 1H NMR and chemical ionization mass spectrometry.


Assuntos
Azul de Eosina I/análise , Fluoresceínas/análise , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
16.
J Chromatogr ; 596(1): 118-22, 1992 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-1522174

RESUMO

Lipoproteins were separated by counter-current chromatography using the type-XLL coil planet centrifuge. The separation was performed with a polymer phase system composed of 16% (w/w) polyethylene glycol 1000 and 12.5% (w/w) dibasic potassium phosphate by eluting the lower phase at a flow-rate of 0.5 ml/min. About 5 ml of the sample solution containing approximately 150 mg of a lipoprotein mixture were loaded. High- and low-density lipoproteins were resolved within 12 h. Each component was detected by gel electrophoresis with oil red staining.


Assuntos
Cromatografia/métodos , Lipoproteínas/sangue , Centrifugação , Cromatografia/instrumentação , Globinas/isolamento & purificação , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Polietilenoglicóis , Albumina Sérica/isolamento & purificação
17.
J Chromatogr ; 550(1-2): 695-704, 1991 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-1663507

RESUMO

Two different types of counter-current chromatographs, the cross-axis coil planet centrifuge (X-axis CPC) and horizontal flow-through coil planet centrifuge (horizontal CPC), were evaluated for protein separation with an aqueous-aqueous two-phase polymer system. The sample solution, containing 10-200 mg each of cytochrome c, myoglobin, ovalbumin and hemoglobin in 2 ml of each phase was eluted with the lower phase. In both instruments, the effects of the flow-rate, revolution speed, and parameter beta (helical diameters of the multilayer coil) on the protein separation were investigated. The best results were obtained from the X-axis CPC operated at 750 rpm and a flow-rate of 2.0 ml/min using a multilayer coil with a small helical diameter (beta = 0.25-0.60). Four protein samples were well resolved in less than 5 h.


Assuntos
Cromatografia Líquida/métodos , Polímeros/análise , Proteínas/análise , Animais , Bovinos , Galinhas , Cromatografia Líquida/instrumentação , Distribuição Contracorrente , Grupo dos Citocromos c/análise , Hemoglobinas/análise , Cavalos , Concentração de Íons de Hidrogênio , Mioglobina/análise , Ovalbumina/análise
18.
J Chromatogr ; 566(1): 67-76, 1991 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-1653259

RESUMO

The separation of normolipidemic male serum lipoprotein fraction, prepared by ultracentrifugal flotation, was studied on hydroxyapatite columns. Potassium phosphate buffers in the pH range 5.6-7.4 were evaluated as eluents. The three main classes of the lipoproteins (high density, low density and very low density) can be separated on the Tiselius-type hydroxyapatite (Bio-Gel HTP DNA grade) column by elution with 75, 250 and 300 mM potassium phosphate buffer (pH 7.4), respectively.


Assuntos
Cromatografia Líquida/métodos , Hidroxiapatitas , Lipoproteínas/sangue , Compostos de Potássio , Soluções Tampão , Durapatita , Humanos , Concentração de Íons de Hidrogênio , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Lipoproteínas VLDL/sangue , Masculino , Fosfatos , Potássio , Ultracentrifugação
19.
J Chromatogr ; 504(1): 69-78, 1990 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-2332461

RESUMO

Eleven kinds of column packing gels which bonded poly(ethylene glycol) (PEG) to Sepharose 6B (PEG-C10-Sepharose) were prepared. Human peripheral blood cells were chromatographed on these gel columns by eluting with 0.09 M phosphate-buffered 2% (w/w) dextran T40 solution at the pH of the respective isoelectric points of the blood cells. The rate of penetration of water or the mobile phases into the PEG-C10-Sepharose xerogels as a measure of the hydrophobicity of the gels depended on both the oxyethylene residue content and the number of oxyethylene units of the packing gels. The capacity factors of granulocytes and lymphocytes were increased on the columns packed with gels having a slower rate of penetration of the liquids into the xerogels.


Assuntos
Células Sanguíneas/citologia , Separação Celular , Cromatografia de Afinidade/métodos , Humanos
20.
J Chromatogr ; 398: 153-64, 1987 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-3654836

RESUMO

The chromatographic behaviour of human peripheral blood cells was investigated on poly(propylene glycol) (PPG)-bonded Chromagel. The mobile phase was 0.09 M phosphate-buffered 2% (w/w) dextran T40 solution at the pH of the respective isoelectric points of human blood cells. The elution order of four kinds of blood cells from PPG-C3-Chromagel columns coincided with that of the delta log K values of these cells determined by the hydrophobic affinity partition method using Pluronic P84 as a hydrophobic ligand. The capacity factors of granulocytes and lymphocytes increased with increase in the delta log K values of PPG-C3-Chromagel beads. Hydrophobic interactions contributed to the retention of the four kinds of blood cells on PPG-bonded Chromagel columns.


Assuntos
Células Sanguíneas , Separação Celular/métodos , Fenômenos Químicos , Físico-Química , Cromatografia de Afinidade , Géis , Humanos , Técnicas In Vitro , Focalização Isoelétrica , Espectroscopia de Ressonância Magnética , Masculino , Polímeros , Propilenoglicóis
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