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1.
Reprod Fertil Dev ; 31(2): 272-281, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30071922

RESUMO

In this study we investigated the effect of astaxanthin (Ax), which exhibits strong antioxidant activity, during invitro growth (IVG) on the developmental competence of oocytes and steroidogenesis of granulosa cells derived from early antral follicles. Bovine oocyte-cumulus-granulosa complexes collected from early antral follicles were cultured for 12 days in the presence or absence (control) of 500µM Ax. The viability of oocytes and antrum formation in the granulosa cell layer during IVG culture were greater in the presence than absence of Ax (P<0.05). Regardless of Ax treatment, 17ß-oestradiol production increased during IVG culture; however, progesterone production was significantly lower in the presence than absence of Ax (P<0.05). Reactive oxygen species levels were lower in Ax-treated oocytes than in controls after IVG (P<0.05). Although nuclear maturation and cleavage rates did not differ between the Ax-treated and control groups, Ax treatment led to weaker cathepsin B activity in oocytes and better blastocyst rates than in controls (P<0.05). Accordingly, Ax treatment during IVG increased the total number of cells in blastocysts (P<0.05). These results indicate that Ax supplementation of IVG medium improves the quality of bovine oocytes due to its antioxidative effects on growing oocytes and its suppression of the luteinisation of granulosa cells.


Assuntos
Antioxidantes/farmacologia , Células da Granulosa/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Oogênese/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Animais , Bovinos , Meios de Cultura , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Células da Granulosa/metabolismo , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Progesterona/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Xantofilas/farmacologia
2.
J Exp Med ; 194(11): 1597-607, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11733574

RESUMO

Mucosal immunoglobulin (Ig)A dominance has been proposed to be associated with preferential class switch recombination (CSR) to the IgA heavy chain constant region, Calpha. Here, we report that B cell activation in nasal-associated lymphoid tissue (NALT) upon stimulation with the hapten (4-hydroxy-3-nitrophenyl)acetyl (NP) coupled to chicken gamma globulin caused an anti-NP memory response dominated by high affinity IgA antibodies. In the response, however, NP-specific IgG(+) B cells expanded and sustained their number as a major population in germinal centers (GCs), supporting the view that CSR to IgG heavy chain constant region, Cgamma, operated efficiently in NALT. Both IgG(+) and IgA(+) GC B cells accumulated somatic mutations, indicative of affinity maturation to a similar extent, suggesting that both types of cell were equally selected by antigen. Despite the selection in GCs, high affinity NP-specific B cells were barely detected in the IgG memory compartment, whereas such cells dominated the IgA memory compartment. Taken together with the analysis of the V(H) gene clonotype in GC and memory B cells, we propose that NALT is equipped with a unique machinery providing IgA-specific enrichment of high affinity cells into the memory compartment, facilitating immunity with high affinity and noninflammatory secretory antibodies.


Assuntos
Afinidade de Anticorpos/imunologia , Linfócitos B/imunologia , Imunoglobulina A/imunologia , Memória Imunológica/imunologia , Cavidade Nasal/imunologia , Administração Intranasal , Animais , Antígenos/imunologia , Antígenos/farmacologia , Células Cultivadas , Quimiotaxia de Leucócito , Centro Germinativo/imunologia , Haptenos/imunologia , Haptenos/farmacologia , Imunoglobulina A/biossíntese , Imunoglobulina G/imunologia , Isotipos de Imunoglobulinas , Injeções Intraperitoneais , Linfonodos/citologia , Linfonodos/imunologia , Tecido Linfoide/citologia , Tecido Linfoide/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Cavidade Nasal/citologia , Nitrofenóis/imunologia , Nitrofenóis/farmacologia , Fenilacetatos
3.
Int J Oral Maxillofac Surg ; 49(8): 984-992, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32070653

RESUMO

The objectives of this study were to evaluate survival in 141 patients with stage II-IV oral squamous cell carcinoma (OSCC) treated with preoperative intra-arterial chemotherapy with docetaxel, cisplatin, and peplomycin combined with intravenous chemotherapy using 5-fluorouracil (IADCPIVF) via the superficial temporal artery, and to clarify the prognostic factors. The study population included 59 patients with stage II OSCC, 34 with stage III, and 48 with stage IV. After IADCPIVF, 139 patients underwent surgery; minimally invasive surgeries (MIS) including excisional biopsy were performed on 96 patients with a remarkably good response to IADCPIVF. The primary tumour response rate was 99.3% (complete response rate 56.7%, good partial response rate 17.0%, fair partial response rate 25.5%). Additionally, there were no serious adverse events associated with IADCPIVF. The 5-year overall survival rate was 74.6% (stage II 83.6%, stage III 72.7%, stage IV 64.8%). In the multivariate analysis of survival, T classification and clinical tumour response were significant prognostic factors. Eight (8.3%) of the patients who received MIS had primary recurrence and six were salvaged. In conclusion, IADCPIVF is safe and efficacious for treating OSCC, and MIS could reduce the extent of primary tumour resection in the case of a remarkably good response.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica , Cisplatino/uso terapêutico , Docetaxel , Fluoruracila , Humanos , Recidiva Local de Neoplasia , Peplomicina/uso terapêutico , Taxoides/uso terapêutico
4.
Biochim Biophys Acta ; 689(1): 121-34, 1982 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-7201855

RESUMO

Plasma membranes were isolated from lactating bovine mammary gland. Two crude membrane fractions; medium/d 1.033 (light membrane) and 1.033/1.053 interfaces (heavy membrane), were obtained by Ficoll density gradient centrifugation of osmotically washed microsomal fraction. Two crude membranes were further purified separately by sucrose density gradient centrifugation. Both light and heavy membranes banded at a sucrose density of 1.14. The purified membranes appeared as heterogeneous smooth membrane vesicles on electron microscopy. The contaminating suborganelles were not detected. The yield of the purified membranes relative to the homogenate was 1.2%. The degree of purity of the membranes was shown by a great increase in the specific activity of 5'-nucleotidase over the homogenate of 20-fold for light membrane and of 16-fold for heavy membrane. The relative activities of Mg2+-ATPase, (Na+ + K+)-ATPase, gamma-glutamyl transpeptidase, phosphodiesterase I, alkaline phosphatase and xanthine oxidase were also high (12-18-times) and nearly 20% of these enzymes was recovered. The activity of marker enzyme for mitochondria, endoplasmic reticulum and Golgi apparatus was very low, while that of acid phosphatase for lysosome was relatively high (5-times). DNA and RNA contents were very low. The major polypeptides rich in other suborganelles were not detected profoundly in the membrane fraction and the polypeptide composition in both light and heavy membranes were similar upon SDS-polyacrylamide gel electorphoresis.


Assuntos
Membrana Celular/ultraestrutura , Lactação , Glândulas Mamárias Animais/ultraestrutura , Animais , Bovinos , Fracionamento Celular/métodos , Centrifugação com Gradiente de Concentração/métodos , Eletroforese em Gel de Poliacrilamida , Feminino , Glândulas Mamárias Animais/fisiologia , Proteínas de Membrana/isolamento & purificação , Microscopia Eletrônica , Peso Molecular , Gravidez
5.
Biochim Biophys Acta ; 1122(2): 203-11, 1992 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-1643094

RESUMO

Two major glycoproteins (PAS-6 and PAS-7) from bovine milk fat globule membrane were selectively extracted with urea and KCl, co-purified by repeated gel filtration on Sephacryl S-200 and then separated by affinity chromatography on concanavalin A-agarose column. The two purified glycoproteins showed a single band by SDS-PAGE, and their molecular masses were estimated to be 50 kDa for PAS-6 and 47 kDa for PAS-7. Both PAS-6 and PAS-7 were resolved several variants by analytical isoelectric focusing. These were shifted to a single band at pI 6.2 for PAS-6 and at pI 6.5 for PAS-7 by neuraminidase. PAS-6 contained 7.1% and PAS-7 5.5% of carbohydrate; the molar ratio of fucose:mannose:galactose:N-acetyl galactosamine:N-acetyl glucosamine:sialic acid was 1.0:3.0:2.0:6.1:5.0:1.3 for PAS-6 and 1.0:3.1:2.2:0:4.1:1.1 for PAS-7. Mild alkaline treatment and affinity to various lectins indicated that PAS-6 had O- and N-linked oligosaccharide chains, while PAS-7 had only the N-linked type. The major amino acid residues of PAS-6 were Glu, Ser and Gly, and those of PAS-7 were Asp, Glu, Gly and Leu. The N-terminal amino acids of both glycoproteins were blocked. PAS-6 and PAS-7 digested with trypsin had a different peptide map, two major peptides having the same retention time on HPLC and being common to PAS-6 and PAS-7 having the same amino acid sequences of H-Gln-Ser-Gly-Asn-Lys-Asn-Pro-Ser-Glu-Ile-Ser-OH and H-Ile-Phe-Pro-Gly-Asn-Met-Asp-Asn-Ser-His-Lys-OH.


Assuntos
Glicoproteínas de Membrana/isolamento & purificação , Leite/análise , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Carboidratos/análise , Cromatografia em Gel , Ponto Isoelétrico , Lectinas , Glicoproteínas de Membrana/química , Dados de Sequência Molecular , Peso Molecular , Mucina-1 , Neuraminidase , Mapeamento de Peptídeos , Tripsina
6.
Biochim Biophys Acta ; 380(2): 282-90, 1975 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-1120147

RESUMO

Human milk was found to contain naturally occuring beta-, gamma- and delta-tocopherol and gamma-tocotrienol in addition to alpha-tocopherol on thin-layer chromatography. Some of the tocopherols were also identified by gas-liquid chromatography and mass spectrometry. The mean content of alpha-, beta-, gamma- and delta-tocopherol was 319.3, 7.6, 23.9 and 4.9 mug/g lipid in twelve human colostra 52.5, 1.8, 10.2 and 2.3 mug/g lipid in three transitional milks and 61.7, 2.0, 9.2 and 1.1 mug/g lipid in three normal milks, respectively. A markedly high concentration of alpha-tocopherol was found in colostrum compared with transitional and normal human milk. Gamma-Tocotrienol was detected in colostrum as only one tocotrienol derivative on thin-layer chromatography. The importance of colostrum as the source of vitamin E for the newborn is suggested.


Assuntos
Leite Humano/análise , Vitamina E/análise , Cromatografia Gasosa , Cromatografia em Camada Fina , Colostro/análise , Feminino , Humanos , Lactação , Espectrometria de Massas , Gravidez , Fatores de Tempo
7.
J Biochem ; 85(2): 529-34, 1979 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33979

RESUMO

Large amounts (66-97%) of marker enzymes such as alkaline phosphatase, 5'-nucleotidase, phosphodiesterase I, and gamma-glutamyl transpeptidase of bovine milk fat globule membrane (MFGM) were selectively solubilized by nonionic detergents such as Triton X-100, Tween 20, Nonidet P-40, Liponox NCK, and Emulgen 109-P. On the other hand, the extractability of MFGM protein with these detergents was less than 50%. Judging from the recovery of total activity, it is likely that alkaline phosphatase, phosphodiesterase I, and gamma-glutamyl transpeptidase are activated by nonionic detergents, whereas 5'-nucleotidase is somewhat inhibited by the detergents, except for Tween 20, and acid phosphatase is strongly inhibited by all detergents. In addition, solubilization of the protein with the nonionic detergents was found to be somewhat selective by SDS-polyacrylamide gel electrophoresis. There was no appreciable difference between the five brands of nonionic detergents used as regards the extractability of protein and the enzymatic activity of the extracted marker enzymes of MFGM, except that the solubilizing ability of Tween 20 was relatively low.


Assuntos
Lipídeos/isolamento & purificação , Leite/enzimologia , Fosfatase Ácida/análise , Fosfatase Alcalina/análise , Animais , Bovinos , Feminino , Nucleotidases/análise , Diester Fosfórico Hidrolases/análise , Tensoativos , gama-Glutamiltransferase/análise
8.
J Nutr Sci Vitaminol (Tokyo) ; 35(6): 649-53, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2634740

RESUMO

The transfer of orally administered alpha-tocopherol (1.1 g) into breast milk reached a maximum value of 414 micrograms/100 g milk, which was 6.6-fold the pre-supplemental level, after three days and declined to the base line level after five days. The amount of alpha-tocopherol recovered in the milk was 0.11%. The alpha-tocopherol equivalent/PUFA ratio (mg/g) was increased from 0.25 to values between 0.7 and 1.7 by the administration.


Assuntos
Leite Humano/metabolismo , Vitamina E/farmacocinética , Administração Oral , Ácidos Graxos Insaturados/metabolismo , Feminino , Humanos , Cinética , Lactação , Gravidez , Vitamina E/administração & dosagem
9.
J Nutr Sci Vitaminol (Tokyo) ; 37(1): 15-27, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1880629

RESUMO

The contents of total, free, and bound vitamin B2 (B2) in bovine milk and their distribution in four separate milk fractions, including milk during the early lactation stage, were estimated. The total B2 content in whole mature milk was 179 +/- 25 micrograms/100 g (n = 16), and its distribution in the cream, whey, skim milk membrane, and casein fractions was 6, 67, 9, and 18%, respectively. The amount of flavins bound to protein in the total B2 was 13.6% in whole milk and rich in membrane fraction. The total B2 content (micrograms/100 g of milk) was higher in colostrum at 1-3 days (287 +/- 120) than in colostrum at 4-7 days (173 +/- 27), in transitional milk (182 +/- 33), and in mature milk (179 +/- 44). The bound flavin content decreased slightly as lactation progressed (20-30 micrograms/100 g), but the ratio of bound/total B2 did not vary (12-15%). Milk fat globule membrane (MFGM) contained 414 +/- 65 micrograms of B2/g of protein, most of it being bound to protein (92%). Market milks contained as much total B2 as raw whole milk, but the amount of bound form was only 2%. Guanidine HC1, urea, sodium dodecyl sulfate, pH at 3.0-3.5, delipidation, and boiling released most of the B2 bound to protein, suggesting that bound flavins bind to milk proteins by a hydrophobic linkage.


Assuntos
Leite/química , Riboflavina/análise , Animais , Bovinos , Fracionamento Químico , Colostro/química , Feminino , Flavinas/análise , Concentração de Íons de Hidrogênio , Proteínas do Leite/análise
12.
J Dairy Sci ; 72(4): 883-91, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2473101

RESUMO

Lactophorin is designated as a glycoprotein, which is present in bovine milk whey and reacts to the antiserum of the soluble glycoprotein of bovine milk fat globule membrane. The lactophorin was purified by DEAE-cellulose (pH 7.7), Sephadex G-100, and then Bio Gel A-15m from the component-3 fraction of the proteose-peptone fraction of bovine milk whey. The purified lactophorin was separated into seven components by DEAE-cellulose chromatography at pH 8.6. The seven components (LP-1 to -7) of lactophorin were almost homogeneous, but the respective bands were somewhat broad and varied in mobilities on disc electrophoresis. The seven lactophorin components fused completely to the antisoluble glycoprotein of milk fat globule membrane on double immunodiffusion but showed different mobilities of precipitation lines on immunoelectrophoresis. The results indicated that lactophorin consisted of multiple forms but had a common set of antigenic determinant groups against anti-soluble glycoprotein.


Assuntos
Glicoproteínas/isolamento & purificação , Proteínas do Leite/isolamento & purificação , Animais , Bovinos , Eletroforese Descontínua , Epitopos , Feminino , Glicoproteínas/análise , Glicoproteínas/imunologia , Imunodifusão , Imunoeletroforese , Proteínas do Leite/análise , Proteínas do Leite/imunologia
13.
J Dairy Sci ; 72(7): 1732-9, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2778161

RESUMO

A glycoprotein that reacted to the antisoluble glycoprotein of bovine milk fat globule membrane was purified from the proteose-peptone of whey and designated lactophorin. Lactophorin was separated into seven components. Lactophorin and the seven components were rich in aspartic acid, threonine, serine, glutamic acid, leucine, and lysine. The content of threonine, glycine, isoleucine, lysine, and arginine varied in each component. The ratio of fucose, mannose, galactose, N-acetylgalactosamine, N-acetylglucosamine, and sialic acid of lactophorin, which contains about 18% saccharide, were 1, 6.6, 10.3, 5.5, 9.7, and 11.6, respectively, while the respective ratio of the seven components were 1, 5 to 6, 7 to 9, 3 to 4, 6 to 8, and 4 to 12. Sialic acid content varied in each component. Protein-carbohydrate linkage was N- and o-glucoside linkage. Lactophorin consisted of seven polypeptides (I to VII) with apparent molecular weights 17,000 to 67,000. Bands I, II, VI, and VII were glycoprotein. Bands VI and VII were major and had antigenicity to anti-soluble glycoprotein, while bands I to V were minor polypeptides. Component 1 consisted of only one polypeptide (VII), whereas the components 2 to 7 contained two major (VI, VII, or both) and several minor polypeptides. The sedimentation pattern of each component was a single and almost symmetrical peak. Sedimentation coefficient was 3.79 to 5.64 S and also varied in lactophorin. The results indicate that lactophorin has multiple forms.


Assuntos
Carboidratos/análise , Bovinos/metabolismo , Proteínas do Leite/análise , Leite/análise , Aminoácidos/análise , Animais , Feminino , Proteínas do Leite/isolamento & purificação , Peso Molecular , Monossacarídeos/análise , Peptídeos/análise , Proteínas do Soro do Leite
14.
J Dairy Res ; 58(4): 421-9, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1765591

RESUMO

Enzymic modification with peptidylarginine deiminase (EC 3.5.3.15) enabled five out of six arginyl residues in alpha s1-casein to be converted to citrullyl residues, only the N-terminal arginyl residue remaining unaffected. An increase in the net negative charge was confirmed by PAGE. The isoelectric point was decreased from 4.46 for the intact alpha s1-casein to 4.30 for the deiminated type, while simultaneously lowering the acid-precipitation starting point from pH 5.17 to pH 4.62. The deiminated alpha s1-casein self-associated less in the absence of Ca and was less Ca-sensitive than the native type, although its Ca-binding ability was slightly enhanced. In the presence of 25 mM-CaCl2 and kappa-casein, Ca-induced precipitation of alpha s1-casein did not occur, the solution of the mixture remaining transparent. Deimination of alpha s1-casein resulted in altering its characteristics, possibly by interfering with interactions through hydrophobicity and/or hydrogen bonding. The positive charge of the arginyl residues might play an important role in casein micelle formation.


Assuntos
Cálcio/metabolismo , Caseínas/metabolismo , Hidrolases/metabolismo , Leite/metabolismo , Aminoácidos/análise , Aminoácidos/química , Animais , Caseínas/química , Bovinos , Precipitação Química , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Feminino , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Mapeamento de Peptídeos , Proteína-Arginina Desiminase do Tipo 4 , Desiminases de Arginina em Proteínas
15.
Biosci Biotechnol Biochem ; 59(5): 848-52, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7787299

RESUMO

The isolation and partial characterization of PAS-4 glycoprotein (78 kDa) from bovine milk fat globule membrane (MFGM) is described. PAS-4 was selectively extracted with Triton X-114 nonionic detergent and then fractionated on DEAE-Sepharose at pH 7.5. The PAS-4 fraction that was not bound on DEAE-Sepharose gave a single band by SDS-PAGE. The recovery of PAS-4 was 57.4% from MFGM. An amino acid analysis found a high percentage of nonpolar residues. Approximately 7.2% of carbohydrate from PAS-4 was composed of mannose, galactose (Gal), N-acetylglucosamine, N-acetylgalactosamine (GalNAc), and sialic acid, most of the Gal and GalNAc in PAS-4 being released after mild alkaline hydrolysis. This indicated that PAS-4 contained both N- and O-linked sugar chains in concordance with the results of lectin affinity. PAS-4 had apparent isoelectric points of 7.45, 7.41, and 7.32, but these were shifted to pI 7.47 by a neuraminidase treatment. The apparent molecular weight of PAS-4 after deglycosylation with N-glycanase was approximately 57,000 by SDS-PAGE.


Assuntos
Antígenos CD36 , Glicoproteínas de Membrana/isolamento & purificação , Leite/química , Animais , Bovinos , Gorduras/química , Feminino , Lectinas/metabolismo , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/metabolismo , Proteínas do Leite/química
16.
Biosci Biotechnol Biochem ; 61(9): 1568-74, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9339560

RESUMO

A monoclonal antibody to the PAS-4 glycoprotein (78 kDa) of the bovine milk fat globule membrane (MFGM) specifically recognized PAS-4, and was named KAS4. A component recognized by KAS4 was found in whey protein, this being a glycoprotein of 88 kDa by SDS-PAGE and named WGP-88. WGP-88 was purified and characterized in comparison with PAS-4. WGP-88 had apparent pI values of 6.45 and 6.39, while those of PAS-4 were 7.39 and 7.35. Neuraminidase digestion shifted the pI values of WGP-88 to 6.57 and of PAS-4 to 7.52. WGP-88 was rich in polar amino residues (44.9 mol%), while PAS-4 was abundant in nonpolar amino acid residues (48.7 mol%). WGP-88 contained 17.1% of carbohydrate and PAS-4 had 7.2%. The results of reductive hydrolysis, N-glycanase digestion, and a lectin blot analysis suggested that N- and O-linked sugar chains were contained in both glycoproteins. WGP-88 and PAS-4 had a different N-terminal amino acid sequence. WGP-88 and PAS-4 respectively inhibited competitively the binding of KAS4 to PAS-4 and WGP-88. Our studies revealed WGP-88 recognized by KAS4 mAb to be a novel whey protein and to have different biochemical properties from those of PAS-4.


Assuntos
Anticorpos Monoclonais/metabolismo , Glicoproteínas de Membrana/imunologia , Proteínas do Leite/isolamento & purificação , Leite/química , Animais , Anticorpos Monoclonais/química , Ascite/metabolismo , Ligação Competitiva , Carboidratos/análise , Bovinos , Lectinas/análise , Lipídeos/química , Proteínas do Leite/análise , Peso Molecular , Mapeamento de Peptídeos , Ligação Proteica
17.
Biosci Biotechnol Biochem ; 56(6): 900-5, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27280811

RESUMO

Two calcium-stimulated ATPases at optimal pH values of 5.0 and 7.0, which are designated as acid and neutral Ca(2+) -ATPase, respectively, were found in the membrane fraction of human milk, and their enzymatic properties were studied. For maximal activity, neutral Ca(2+)-ATPase required 0.45 mM Ca ion, while acid Ca(2+) -ATPase required 207 mM Ca ion. Neutral Ca(2+) -ATPase activity was not enhanced by adding the Mg ion at more than 0.1 mM. Among the nucleotides, neutral Ca(2+) -ATPase showed a higher substrate specificity to GTP, CTP, ITP, and UTP than to ATP, while ATP was the best substrate for acid Ca(2+) -ATPase. Neutral and acid Ca(2+) -ATPases had apparent Km values of 0.361 and 0.192 mM, and Vmax of 186 and 178 µmol ATP hydrolyzed/mg of protein per min, respectively. Both Ca(2+) -ATPases were potently inhibited by fluoride, lanthanide, vanadate, and p-chloromercuribenzoate, and inactivated by EDTA, EGTA, and CDTA, but were unaffected by N-ethylmaleimide, NaN3, ouabain, oxidized glutathione, or oligomycin, and were inactivated by heating at 60°C for 10 min. These enzymes were concentrated in the membrane fraction of the cream and skim milk membrane.

18.
Glycoconj J ; 15(4): 361-9, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9613823

RESUMO

The structures of the N-linked sugar chains in the PAS-6 glycoprotein (PAS-6) from the bovine milk fat globule membrane were determined. The sugar chains were liberated from PAS-6 by hydrazinolysis, and the pyridylaminated sugar chains were separated into a neutral (6N) and two acidic chains (6M and 6D), the acidic sugar chains then being converted to neutral sugar chains (6MN and 6DN). 6N was separated into two neutral fractions (6N13 and 6N5.5), while 6MN and 6DN each gave a single fraction (6MN13 and 6DN13). The structure of 6N5.5, which was the major sugar chain in PAS-6, is proposed to be Man alpha1 --> 6 (Man alpha1 --> 3) Man beta1 --> 4GlcNAc beta1 --> 4GlcNAc-PA; 6N13, 6MN13 and 6DN13 are proposed to be Gal beta1 --> 3Gal beta1 --> 4GlcNAc beta1 --> 2Man alpha1 --> 6 (Gal beta1 --> 3Gal beta1 --> 4GlcNAc beta1 --> 2Man alpha1 --> 3) Man beta1 --> 4GlcNAc beta1 --> 4 (Fuc alpha1 --> 6)GlcNAc-PA; 6M and 6D had 1 or 2 additional NeuAc residues at the non-reducing ends of 6MN13 and 6DN13, respectively.


Assuntos
Carboidratos/química , Glicolipídeos/química , Glicoproteínas/química , Glicoproteínas de Membrana/química , Proteínas do Leite/química , Animais , Configuração de Carboidratos , Sequência de Carboidratos , Carboidratos/isolamento & purificação , Bovinos , Feminino , Humanos , Gotículas Lipídicas , Metilação , Dados de Sequência Molecular , Estrutura Molecular
19.
Cell Struct Funct ; 12(2): 141-55, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2954657

RESUMO

Immunoreactive opsin was detectable in the apical portion of normally developing photoreceptor cells on postnatal day 3 by the indirect enzyme-labeled antibody method. Immunoreactivity increased and had extended from the central retina to the periphery by the advanced stages of development. In the rd mutant retinas, accumulated opsin was present in the apical portion and in the outer nuclear layer on postnatal day 8. Immunoreactive opsin mainly was present in the outer nuclear layer by day 14, even being detectable on day 28. No immunoreactivity was present in the remaining cones. Electron microscopic immunocytochemistry confirmed the association of immunoreactive opsin with the persistent rod cell plasma membrane. Molecular weight of immunoreactive opsin in 14-day-old rd mutant mouse retina, as estimated by gel filtration chromatography, was large and did not seem to be degraded. These findings indicate that accumulated rhodopsin continues to function in the plasma membrane because an electroretinogram could be made after day 14 for the rd mutant mouse retina.


Assuntos
Proteínas do Olho/metabolismo , Células Fotorreceptoras/metabolismo , Pigmentos da Retina/metabolismo , Segmento Externo da Célula Bastonete/metabolismo , Animais , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Ensaio de Imunoadsorção Enzimática , Histocitoquímica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Camundongos Mutantes , Microscopia Eletrônica , Células Fotorreceptoras/ultraestrutura , Segmento Externo da Célula Bastonete/ultraestrutura , Opsinas de Bastonetes
20.
Immunology ; 97(1): 9-17, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10447709

RESUMO

To understand the biological function of natural immunoglobulin A (IgA) antibodies in Peyer's patches (PP), we generated IgA monoclonal antibody (mAb) clones from the PP of normal, unimmunized, specific pathogen-free BALB/c mice and examined their reactivities by enzyme-linked immunosorbent assay (ELISA). Many of these antibodies reacted with more than one antigen examined, suggesting that they were polyreactive Abs. Two mAbs agglutinated several different strains of commensal bacteria isolated from mice. To examine the genetic features of these polyreactive mAbs, the VH genes of seven different IgA mAbs were sequenced. The VH genes from the VGAM, J558 and 7183 families were compared with sequence from the mAbs with distinct VDJ rearrangements. One of the mAbs that agglutinated bacteria was encoded by a germline VH gene, but the VH region of the other polyreactive mAbs contained between seven and 11 mutated sites. No indication of antigenic selection was observed in the pattern of these mutated sites. Our results show that polyreactive IgA Abs are present in PP as a part of the normal B-cell repertoire. These polyreactive Abs may establish a natural immune homeostasis, and function as a polyreactive sensor to detect pathogenic invasion and to control immune response in the gut.


Assuntos
Imunoglobulina A/biossíntese , Nódulos Linfáticos Agregados/imunologia , Aglutinação , Animais , Anticorpos Monoclonais/genética , Especificidade de Anticorpos , Reações Antígeno-Anticorpo/imunologia , Antígenos de Bactérias/imunologia , Sequência de Bases , Relação Dose-Resposta Imunológica , Feminino , Hibridomas/imunologia , Imunoglobulina A/genética , Imunoglobulina A/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular
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