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1.
Phys Rev Lett ; 118(5): 052701, 2017 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-28211732

RESUMO

The cross sections of the ^{7}Be(n,α)^{4}He reaction for p-wave neutrons were experimentally determined at E_{c.m.}=0.20-0.81 MeV slightly above the big bang nucleosynthesis (BBN) energy window for the first time on the basis of the detailed balance principle by measuring the time-reverse reaction. The obtained cross sections are much larger than the cross sections for s-wave neutrons inferred from the recent measurement at the n_TOF facility in CERN, but significantly smaller than the theoretical estimation widely used in the BBN calculations. The present results suggest the ^{7}Be(n,α)^{4}He reaction rate is not large enough to solve the cosmological lithium problem, and this conclusion agrees with the recent result from the direct measurement of the s-wave cross sections using a low-energy neutron beam and the evaluated nuclear data library ENDF/B-VII.1.

2.
Biochim Biophys Acta ; 1163(3): 243-9, 1993 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-8507662

RESUMO

The amino-acid sequence of purified recombinant pro-major basic protein from Chinese hamster kidney cells was determined to verify the primary structure and glycosylation sites. Reduced and S-carboxamidemethylated protein was first digested with Achromobacter proteinase I. Each peptide was characterized by amino-acid analysis and amino-acid sequence analysis. We could identify all the peptides which were expected from the pro-major basic protein cDNA sequence. Sequence analysis and deglycosylation study revealed that Ser-8, Thr-9, Ser-46 and Asn-70 were glycosylated. The results indicated that proMBP has three types of sugar chains, O-glycoside, N-glycoside and glycosaminoglycan, in the pro-portion.


Assuntos
Proteínas Sanguíneas/química , Glicoproteínas/química , Monossacarídeos/análise , Precursores de Proteínas/química , Ribonucleases , Sequência de Aminoácidos , Animais , Asparagina/química , Proteínas Sanguíneas/metabolismo , Cricetinae , Proteínas Granulares de Eosinófilos , Glicopeptídeos/química , Glicoproteínas/metabolismo , Glicosilação , Dados de Sequência Molecular , Mapeamento de Peptídeos , Precursores de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Sinais Direcionadores de Proteínas/química , Sinais Direcionadores de Proteínas/metabolismo , Análise de Sequência , Serina/química , Serina Endopeptidases/metabolismo , Treonina/química
3.
Diabetes ; 46(12): 2075-81, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9392499

RESUMO

Mononuclear cells, including monocytes/macrophages and T-cells, are considered to be involved in the progression of diabetic nephropathy, although the mechanism of their recruitment into diabetic glomeruli is unclear. The intercellular adhesion molecule-1 (ICAM-1) promotes the infiltration of leukocytes into atherosclerotic lesions as well as inflammatory tissues. In the present study, we investigated the expression of ICAM-1 in the glomeruli of streptozotocin-induced diabetic rats. The expression of ICAM-1 was increased significantly during the early stage of diabetes. The number of mononuclear cells, primarily monocytes/macrophages and lymphocytes, was significantly increased in diabetic glomeruli. Mononuclear cell infiltration into diabetic glomeruli was prevented by anti-ICAM-1 monoclonal antibody. Insulin treatment decreased ICAM-1 expression and mononuclear cell infiltration. The ICAM-1 expression on cultured human umbilical vein endothelial cells was not induced under high glucose culture conditions. Glomerular hyperfiltration is a characteristic change in the early stage of diabetic nephropathy. Treatment with aldose reductase inhibitor, which prevented glomerular hyperfiltration without changes in blood glucose levels, decreased ICAM-1 expression and mononuclear cell infiltration. Moreover, we examined the ICAM-1 expression in the glomeruli of the 5/6 nephrectomized rat, which is a model for glomerular hyperfiltration without hyperglycemia. The ICAM-1 expression and infiltration of mononuclear cells was significantly increased in the glomeruli of 5/6 nephrectomized rats. We conclude that ICAM-1 is upregulated and promotes the recruitment of mononuclear cells in diabetic glomeruli. Moreover, glomerular hyperfiltration that occurs in the early stage of diabetic glomeruli may be one of the potential mechanisms of ICAM-1 upregulation in diabetic nephropathy.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Glomérulos Renais/metabolismo , Aldeído Redutase/antagonistas & inibidores , Animais , Anticorpos Monoclonais/farmacologia , Células Cultivadas , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/patologia , Endotélio Vascular/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Imuno-Histoquímica , Insulina/uso terapêutico , Molécula 1 de Adesão Intercelular/imunologia , Glomérulos Renais/patologia , Linfócitos/patologia , Macrófagos/patologia , Masculino , Monócitos/patologia , Nefrectomia , Ratos , Ratos Sprague-Dawley , Veias Umbilicais
4.
Mol Immunol ; 29(4): 537-46, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1565101

RESUMO

We have purified a novel immunoregulatory factor (BMPG: bone-marrow proteoglycan) produced by a T-cell hybridoma, with a monoclonal antibody column. Using an oligonucleotide probe corresponding to the partial amino acid sequence of BMPG, we cloned, sequenced, and expressed a cDNA for BMPG. BMPG has 222 amino acid residues with a 16 N-terminal signal sequence, so the mature form has 206 amino acid residues. BMPG was found to have unique characteristics: it has three types of sugar chains and it shows a marked homology with animal lectins including the human asialoglycoprotein receptor, chicken hepatic lectin and the homing receptor of lymphocytes.


Assuntos
Proteínas Sanguíneas , DNA/análise , Lectinas/genética , Proteoglicanas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Cromatografia de Afinidade , Clonagem Molecular , DNA/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Proteína Básica Maior de Eosinófilos , Humanos , Hibridomas , Células Matadoras Naturais/imunologia , Dados de Sequência Molecular , Mapeamento de Nucleotídeos , Proteoglicanas/imunologia , Proteoglicanas/isolamento & purificação , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico , Linfócitos T/metabolismo
5.
J Biochem ; 85(3): 699-704, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-429260

RESUMO

The rates of synthesis and degradation of arginosuccinate synthetase in rat liver under various dietary conditions were determined. The relative rate of the enzyme synthesis in the livers of rats fed on 70% casein diet was 4.0 times greater than that for rats fed on 5% casein diet. The rate constants of degradation (Kd of argininosuccinate synthetase were estimated to be 0.15 and 0.16 day-1 under 70% and 5% casein feeding, respectively. When the dietary conditions were changed acutely from 70% to 5% casein diet or vice versa, the rates of the enzyme synthesis decreased or increased, respectively, and the rates of enzyme degradation were also affected. The change from 5% to 70% casein diet caused a transient decrease in the rate of degradation. After the enzyme activity had achieved a new steady-state level, the enzyme degradation proceeded at the normal steady rate. On the other hand, the change from 70% to 5% casein diet caused a transient increase in the rate of degradation. Thus, the only factor regulating the amount of enzyme in rat liver is the rate of enzyme synthesis under the steady-state conditions. However, the rates of both enzyme synthesis and degradation are involved in the regulation of the amount of enzyme during dietary transition.


Assuntos
Argininossuccinato Sintase/metabolismo , Proteínas Alimentares/metabolismo , Ligases/metabolismo , Fígado/enzimologia , Animais , Caseínas/metabolismo , Leucina/metabolismo , Masculino , Proteínas/metabolismo , Ratos
6.
Biophys Chem ; 61(2-3): 63-72, 1996 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-8956480

RESUMO

Using an in vitro motility assay on acto-H-meromyosin, we studied the sliding velocity of an actin filament driven by two kinds of H-meromyosin heads: H-meromyosin head with ATP bound (fast motor) and with GTP bound (slow motor). We found a significant increase in the sliding velocity owing to the coexistence of the fast motor and the slow motor. This phenomenon may give an important suggestion with regard to the integration over multiple interactions of H-meromyosin heads along the actin filament.


Assuntos
Actinas/metabolismo , Trifosfato de Adenosina/metabolismo , Guanosina Trifosfato/metabolismo , Subfragmentos de Miosina/metabolismo , Animais , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Guanosina Difosfato/farmacologia , Cinética , Músculo Esquelético/metabolismo , Ligação Proteica , Coelhos
7.
Diabetes Res Clin Pract ; 53(3): 149-59, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11483230

RESUMO

Glomerular hyperfiltration plays a pathogenic role in the early stages of diabetic nephropathy. Experimental studies in laboratory animals suggest that nitric oxide (NO) might be involved in the pathogenesis of glomerular hyperfiltration. We performed a cross-sectional study to determine the relationship between diabetic glomerular hyperfiltration and the NO system. Normoalbuminuric (n=41), microalbuminuric (n=25), and macroalbuminuric (n=16) patients with type 2 diabetes were recruited in this study and compared with age-matched 84 non-diabetic control subjects. Creatinine clearance and urinary NO(2)(-)/NO(3)(-) excretion (urinary NOx) were measured, and the expression of endothelial cell nitric oxide synthase (ecNOS) was evaluated in human renal tissues. Glomerular hyperfiltration was present in 19 (37.5%) and nine (36.6%) of normoalbuminuric and microalbuminuric type 2 diabetic patients, respectively. The urinary NOx was significantly higher in normoalbuminuric patients compared with normal subjects. Creatinine clearance correlated significantly with urinary NOx in normoalbuminuric and microalbuminuric patients. Immunohistochemical staining intensities for ecNOS were significantly increased in glomerular endothelial cells of microalbuminuric type 2 diabetic patients as compared with the control subjects. These results suggest that NO may contribute to the pathogenesis of glomerular hyperfiltration in Japanese type 2 diabetic patients.


Assuntos
Albuminúria , Diabetes Mellitus Tipo 2/fisiopatologia , Taxa de Filtração Glomerular/fisiologia , Óxido Nítrico/fisiologia , Adulto , Fatores Etários , Idoso , Animais , Glicemia/metabolismo , Pressão Sanguínea , Creatinina/sangue , Creatinina/urina , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/urina , Di-Hidrolipoamida Desidrogenase/análise , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Hemoglobinas Glicadas/análise , Humanos , Glomérulos Renais/enzimologia , Masculino , Pessoa de Meia-Idade , Nitratos/urina , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo III , Nitritos/urina , Valores de Referência
8.
J Chromatogr A ; 930(1-2): 165-9, 2001 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-11681574

RESUMO

Peak areas, peak heights, and apparent theoretical plate numbers were examined as a function of sample injection times by use of the batch-type CL detection cell. Comparing the experimental data with those obtained by absorption detector, some considerations were carried out about the peak shape. The peak shape in CL detection was influenced by not only concentration distribution of sample in a sample zone but also sample diffusion and CL reaction at the capillary outlet. The sample injection time of ca. 35 s was recommended for the present CE with CL detector. The injection time much influenced peak shape as well as sensitivity in the CL detection cell.


Assuntos
Eletroforese Capilar/instrumentação , Medições Luminescentes
9.
Respir Med ; 89(4): 271-8, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7597266

RESUMO

Clinical and pathological studies on cryptogenic organizing pneumonitis (COP) were performed in 19 cases diagnosed with transbronchial lung biopsy (TBLB). All patients suffered from fever and several respiratory symptoms. Laboratory data showed increases in erythrocyte sedimentation rate, positivity for C-reactive protein, negative tuberculin reactions and increases in complement level. Pathological findings demonstrated that there were two kinds of organizing processes. Fourteen of the 19 cases were treated with prednisolone, and two cases were observed without administration. The remaining three cases could not be followed up after therapy. In 11 of the 16 cases, abnormal shadows in chest X-ray disappeared, but remained present in five cases. As for the relationship between pathological findings and shadows in chest X-ray, Masson bodies without fibrin were observed in the 11 cases which were without shadows on X-ray, but Masson bodies containing or related to fibrin were observed in the five cases in which abnormal shadows remained. These results suggest that there are two types of organizing process in COP. Type I is an unexplained organizing process in which fibrin is not present or involved. It responds well to steroids and the prognosis is favourable. Type II is an organizing process which involves fibrin, and the character of the fibroblast-like cells is very similar to that of myofibroblasts. Type II organizing process responds poorly to steroids. Both processes can be notified relatively easily, even by TBLB tissues.


Assuntos
Pneumonia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fibrina , Fibroblastos/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia/diagnóstico , Pneumonia/tratamento farmacológico , Prednisolona/uso terapêutico , Prognóstico , Alvéolos Pulmonares/patologia
10.
Diabetologia ; 48(11): 2402-11, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16231067

RESUMO

AIMS/HYPOTHESIS: Recent studies have shown that the inflammatory process is involved in the pathogenesis of diabetic nephropathy. Fourteen-membered ring macrolides, including erythromycin, have anti-inflammatory, as well as antibacterial effects. The aim of this study was to investigate the renoprotective effects of erythromycin in streptozotocin (STZ)-induced diabetic rats. METHODS: STZ-induced diabetic rats were treated orally with erythromycin (5 mg/kg body weight) or vehicle every day for 8 weeks. To evaluate the effect of erythromycin treatment, we measured urinary albumin excretion, and examined the following in the kidney: histological changes, the expression of intercellular adhesion molecule-1 (ICAM-1), macrophage infiltration, and nuclear factor-kappa B (NF-kappaB) activity. RESULTS: Erythromycin significantly reduced urinary albumin excretion without affecting blood glucose levels and blood pressure. Erythromycin also attenuated glomerular hypertrophy, mesangial expansion, macrophage infiltration and ICAM-1 expression in renal tissues. The expression of the gene encoding TGFB1 (also known as TGF-beta1), type IV collagen protein production and NF-kappaB activity in renal tissues were increased in diabetic rats and reduced by erythromycin treatment. CONCLUSIONS/INTERPRETATION: Erythromycin prevented renal injuries without changes of blood glucose levels and blood pressure in experimental diabetic rats. These results suggest that the renoprotective effects of erythromycin are based on its anti-inflammatory effect via suppression of NF-kappaB activation. Modulation of microinflammation with erythromycin may provide a new approach for diabetic nephropathy.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Diabetes Mellitus Experimental/complicações , Nefropatias Diabéticas/prevenção & controle , Eritromicina/farmacologia , Rim/efeitos dos fármacos , Albuminúria/tratamento farmacológico , Animais , Quimiocina CCL2/efeitos dos fármacos , Quimiocina CCL2/genética , Colágeno Tipo IV/efeitos dos fármacos , Colágeno Tipo IV/genética , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/patologia , Molécula 1 de Adesão Intercelular/metabolismo , Rim/patologia , Rim/fisiologia , Macrófagos/efeitos dos fármacos , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley , Estreptozocina/toxicidade , Fator de Transcrição RelA/efeitos dos fármacos , Fator de Transcrição RelA/metabolismo , Fator de Crescimento Transformador beta/efeitos dos fármacos , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta1
11.
Nihon Kyobu Shikkan Gakkai Zasshi ; 32(6): 550-4, 1994 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-8089942

RESUMO

Idiopathic organizing pneumonia (OP) was classified pathologically into two types, and the clinical profiles were compared. Cases in which fibrin in Masson bodies, alpha-sm-actin and m-actin antibodies were negative were regarded as type I (14 cases), and those in which they were positive as type II (7 cases). No significant differences in age and sex were observed between the two groups. As to clinical symptoms and laboratory findings, dyspnea and CRP positivity were observed more frequently and inflammatory reactions were stronger, in type II than in type I. The two groups could not be distinguished by chest X-ray findings. With regard to treatments and outcome, chest X-ray shadows disappeared completely after steroid therapy in type I, and no deaths occurred despite recurrence in some cases. In type II, chest X-ray shadows partially remained in all cases even after steroid therapy, recurrence was rare, and death occurred in some cases due to exacerbations of the initial episode. These observations suggest that there are two pathological types of OP and that the differences in clinical symptoms, laboratory findings, treatments, and prognosis between the two types must be taken into consideration in treating OP.


Assuntos
Doenças Pulmonares Intersticiais/diagnóstico , Actinas/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/análise , Bronquiolite Obliterante/diagnóstico , Bronquiolite Obliterante/imunologia , Feminino , Fibrina/análise , Humanos , Imuno-Histoquímica , Doenças Pulmonares Intersticiais/imunologia , Masculino , Pessoa de Meia-Idade , Prognóstico
12.
J Biol Chem ; 265(13): 7604-9, 1990 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-2159004

RESUMO

Human lymphotoxin (hLT) and its mutant genes have been constructed by in vitro mutagenesis and expressed in Escherichia coli. A deletion of Lys84 to Lys89 in hLT remarkably enhanced both the cytotoxicity against human WiDr cells (colon adenocarcinoma cell line) and the prostaglandin E2-inducing activity toward human synovial cells by approximately 1000- and 50-fold, respectively. The enhanced biological potency coincided with an increase of receptor binding affinity. Circular dichroism studies and the heat and folding stabilities were similar to those of the native form. We propose that the region of Lys84 to Lys89 forms a loop structure at the hLT molecular surface and plays an important role in modulating the receptor binding and biological activities of hLT.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Deleção Cromossômica , Linfotoxina-alfa/genética , Mutação , Receptores de Superfície Celular/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Dicroísmo Circular , Clonagem Molecular , Escherichia coli/genética , Genes , Vetores Genéticos , Humanos , Cinética , Linfotoxina-alfa/metabolismo , Linfotoxina-alfa/farmacologia , Lisina , Camundongos , Dados de Sequência Molecular , Conformação Proteica , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico
13.
Biochem J ; 283 ( Pt 1): 307-11, 1992 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-1567376

RESUMO

The unique glutathione S-transferase (GST) subunit Yx, which is undetectable in normal adult rat liver cytosol, was shown to occur in the liver cytosol of rats with hereditary hyperbilirubinuria (EHB). The Yx subunit is a member of the Alpha-class GST subunits, and is immunologically closely related to the Yc subunit. The Yx subunit has an apparent M(r) of 26,400, different from those of Ya (M(r) 25,800), Yb1 and Yb2 (both M(r) 27,200) and Yc (M(r) 28,400). During postnatal development in livers of EHB rats, the Yx subunit concentration in either sex was highest during the first week post partum and declined rapidly with age. Although the concentration of subunit Yx at 8 weeks of age accounted for about 60% in females and 40% in males of that observed in 1-week-old 'neonatal' male EHB rats, concentrations in females thereafter increased gradually to almost the neonatal level and remained at this high level at least up to 37 weeks of age, whereas the concentration in males did not increase again. Thus the post-pubertal Yx subunit concentration was 2-fold higher in females than in males. In contrast, in normal Sprague-Dawley rat liver, the Yfetus subunit, with the same M(r) as the Yx subunit, had the highest concentration in 10-day-old animals, declined rapidly thereafter, and was not detectable in the post-pubertal period. The Yfetus subunit was also immunoreactive with an antibody against GST YcYc. The analysis of GST subunits by reverse-phase h.p.l.c. revealed that the Yx subunit was eluted at a retention time different from other known subunits, but coincided with that of Yfetus. The N-terminal amino acid sequence of the Yx subunit displayed a high degree of sequence similarity to that of the Yfetus subunit. These data suggest that the Yx subunit in EHB rats may be very similar to, if not identical with, the Yfetus subunit.


Assuntos
Feto/enzimologia , Glutationa Transferase/metabolismo , Hiperbilirrubinemia Hereditária/enzimologia , Fígado/enzimologia , Sequência de Aminoácidos , Animais , Western Blotting , Cromatografia Líquida de Alta Pressão , Citosol/enzimologia , Feminino , Glutationa Transferase/fisiologia , Immunoblotting , Fígado/crescimento & desenvolvimento , Substâncias Macromoleculares , Masculino , Dados de Sequência Molecular , Gravidez , Ratos , Ratos Endogâmicos , Ratos Mutantes
14.
Nephron ; 80(4): 408-13, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9832639

RESUMO

Mannan binding protein (MBP) is a C-type lectin and has a high affinity to mannose and N-acetyl glucosamine. It is also known to activate C4 and C2 without C1 component, which is called 'lectin pathway'. We now report the presence of MBP and MBP-mediated complement activation in renal glomeruli of IgA nephropathy patients using an immunohistochemical method. In 7 of 42 cases with IgA nephropathy, MBP was detected in the glomerular mesangial area and colocalized with IgA1. In 19 cases with other types of IC-mediated glomerulonephritis including lupus nephritis and membranous nephropathy or without nephritis, MBP was not detected in the glomerulus. The C2- and/or C4-positive rate was 87.5% in the MBP-positive group and 20% in the MBP-negative group of IgA nephropathy. In addition, MBP-positive cases showed marked mesangial cell proliferation, lower creatinine clearance (53.4 +/- 10.0 vs. 77. 8 +/- 4.7 ml/min) and higher urinary protein excretion (2.5 +/- 0.9 vs. 0.9 +/- 0.2 g/day) compared with MBP-negative cases. These findings suggested that MBP was involved in glomerular complement activation through the lectin pathway and thus induced glomerular injury of IgA nephropathy. Since oligosaccharide chain alterations such as reduced sialic acid and galactose of IgA1 molecule have been reported in IgA nephropathy patients, MBP might bind to the IgA1 molecule via interaction between MBP and sugar chain.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Transporte/fisiologia , Ativação do Complemento/fisiologia , Glomerulonefrite por IGA/metabolismo , Glomérulos Renais/metabolismo , Adulto , Divisão Celular/fisiologia , Colectinas , Complemento C2/metabolismo , Complemento C2/fisiologia , Complemento C4/metabolismo , Complemento C4/fisiologia , Glomerulonefrite por IGA/sangue , Glomerulonefrite por IGA/patologia , Humanos , Imuno-Histoquímica , Glomérulos Renais/patologia , Pessoa de Meia-Idade
15.
J Biol Chem ; 266(32): 21709-17, 1991 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-1939195

RESUMO

In the adult dog liver cytosol we identified four glutathione S-transferase (GST) subunits, Yd1 (Mr 26,000), Yd2 (Mr 27,000), Yd3 (Mr 28,000), and Ydf (Mr 27,400), and purified GST forms comprising Yd1, Yd2, and Yd3, to apparent homogeneity. Unlike rat transferases the enzyme activity toward 1,2-dichloro-4-nitrobenzene (DCNB) was not retained on the affinity column. Thus the DCNB-active enzyme, GST YdfYdf, from the flow-through fraction of the affinity column was also purified to homogeneity by gel filtration, DE52 chromatography, chromatofocusing, and hydroxylapatite column chromatography. Immunoblot analysis of dog GSTs revealed that the subunits Yd1, Yd2, and Yd3 belong to the pi, alpha, and mu class, respectively. On the contrary, Ydf had no reactivity with antibodies raised against any of the three classes of GST. Each subunit, Yd1, Yd2, Yd3, and Ydf, was distinguishable by its own retention time on reverse-phase high performance liquid chromatography. N-terminal amino acid sequences of the dog GSTS Yd1Yd1 and Yd3Yd3 revealed a high degree of homology to the pi and mu class transferases from rat, human, and mouse, respectively, while the N terminus of Yd2Yd2 is blocked. N-terminal amino acid sequences of GST YdfYdf showed no homology to any of the three classes of GST. The most significant property noted of GST YdfYdf is the high specific activity toward DCNB, exceeding by 1 order of magnitude the corresponding values for the known mu class GSTs. The present results strongly suggest that dog GST YdfYdf is a unique enzyme distinct from the hitherto characterized GST isozymes.


Assuntos
Glutationa Transferase/metabolismo , Isoenzimas/metabolismo , Fígado/enzimologia , Nitrobenzenos/metabolismo , Sequência de Aminoácidos , Animais , Western Blotting , Cromatografia de Afinidade , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Citosol/enzimologia , Cães , Eletroforese em Gel de Poliacrilamida , Glutationa Transferase/genética , Glutationa Transferase/isolamento & purificação , Humanos , Imunodifusão , Isoenzimas/genética , Isoenzimas/isolamento & purificação , Cinética , Substâncias Macromoleculares , Masculino , Dados de Sequência Molecular , Peso Molecular , Homologia de Sequência do Ácido Nucleico , Especificidade por Substrato
16.
Biosci Biotechnol Biochem ; 62(6): 1211-5, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9692206

RESUMO

The structure of the N-linked carbohydrate chains of peptide isomerase from the venom of the funnel web spider (Agelenopsis aperta) has been analyzed. Carbohydrates were released from peptide isomerase by hydrazinolysis and reductively aminated with 2-aminopyridine. The fluorescent derivatives were purified by phenol/chloroform extraction, followed by size-exclusion HPLC. The structure of the purified pyridylamino (PA-) carbohydrate chains were analyzed by a combination of two-dimensional HPLC mapping, sugar composition analysis, sequential exoglycosidase digestions, and mass spectrometry. The peptide isomerase contains six kinds of N-linked carbohydrate chains of truncated high-mannose type, with a fucose alpha 1-6 linked to the reducing N-acetylglucosamine in approximately 80% of them.


Assuntos
Isomerases de Aminoácido/química , Poliaminas/análise , Venenos de Aranha/análise , Aminopiridinas , Configuração de Carboidratos , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Dados de Sequência Molecular
17.
Nephron ; 83(2): 160-4, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10516496

RESUMO

Paraneoplastic nephrotic syndrome is rare, bur occurs mostly in lung cancer. The glomerular lesion usually exhibits membranous nephropathy. Although surgical therapy has been shown to be effective, the treatment of a paraneoplastic nephrotic syndrome has always been a challenge. Currently no standard therapy has been established, if the paraneoplastic nephrotic syndrome is associated with advanced cancer with unresectable lesions. We present 2 cases having paraneoplastic nephrotic syndrome associated with advanced squamous cell carcinoma of the lung. Radiation therapy of the primary tumor effectively caused regression of the paraneoplastic nephrotic syndrome without affecting the renal function. Our results suggest that irradiation can be the first choice in the treatment of nephrotic syndrome, if the primary tumor is unresectable.


Assuntos
Neoplasias Pulmonares/complicações , Síndrome Nefrótica/etiologia , Síndrome Nefrótica/radioterapia , Idoso , Edema/radioterapia , Glomerulonefrite Membranosa/diagnóstico por imagem , Glomerulonefrite Membranosa/etiologia , Glomerulonefrite Membranosa/radioterapia , Humanos , Rim/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Síndrome Nefrótica/diagnóstico por imagem , Síndromes Paraneoplásicas/radioterapia , Proteinúria/etiologia , Proteinúria/patologia , Proteinúria/radioterapia , Tomografia Computadorizada por Raios X
18.
Biochem Biophys Res Commun ; 257(1): 234-8, 1999 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-10092539

RESUMO

Human mesangial cells (HMCs) respond to angiotensin II stimulation, which modulates their physiological activities, i.e., contraction and proliferation. It has been revealed that focal adhesion kinase (FAK) and paxillin participate in the angiotensin II-mediated signaling and cytoskeletal rearrangements at focal adhesion. We investigated the influences of cell adhesion upon angiotensin II effects in HMCs. In adherent cells, both FAK and paxillin were tyrosine phosphorylated by angiotensin II, while the cell detachment completely inhibited the tyrosine phosphorylation of paxillin. Activation of p44/42 mitogen-activated protein (MAP) kinase by angiotensin II was accentuated in suspended cells. Moreover, p190, a member of Rho GTPase activating protein (GAP), and RasGAP were coprecipitated with paxillin in adherent cells and angiotensin II stimulation reduced the formation of paxillin-p190 and paxillin-RasGAP complexes. These results suggest that the formation of focal adhesion complexes accelerated by accumulation of mesangial matrices may inhibit the proliferation of HMCs by modulating MAP kinase activity and be related to mesangial cell depletion.


Assuntos
Angiotensina II/farmacologia , Adesão Celular/efeitos dos fármacos , Mesângio Glomerular/metabolismo , Fatores de Troca do Nucleotídeo Guanina , Proteínas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adesão Celular/fisiologia , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Proteínas do Citoesqueleto/metabolismo , Ativação Enzimática/efeitos dos fármacos , Matriz Extracelular/metabolismo , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Proteínas Ativadoras de GTPase , Mesângio Glomerular/citologia , Mesângio Glomerular/efeitos dos fármacos , Mesângio Glomerular/enzimologia , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Nucleares/metabolismo , Paxilina , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Fosfotirosina/metabolismo , Testes de Precipitina , Ligação Proteica/efeitos dos fármacos , Proteínas Tirosina Quinases/metabolismo , Proteínas Repressoras
19.
Res Commun Mol Pathol Pharmacol ; 95(2): 115-28, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9090749

RESUMO

One of the major causes of glomerular sclerosis which precedes renal failure is an increase in glomerular extracellular matrices (ECMs). Glomerular ECMs which are composed of mesangial matrix and basement membrane play an important role in physical, mechanical and structural functions of the glomerulus. Matrix metalloproteinases (MMPs) are the enzymes which degrade both the collagenous and noncollagenous components of the ECMs. Tissue inhibitors of metalloproteinases (TIMPs) are inhibitors of MMPs. The regulations by MMPs and TIMPs are considered to contribute to maintain homeostasis in the production and degradation of ECMs in the glomeruli. In the glomeruli of patients with glomerulonephritis, the imbalance between production and degradation of ECMs is supposed to cause the increase in ECMs and glomerular sclerosis. In this study, serum concentrations of MMP-1, -2, and -3, TIMP-1 and 2 and type IV collagen were measured in patients with IgA nephropathy, lupus nephritis and membranous nephropathy. In patients with IgA nephropathy and lupus nephritis which are mesangial proliferative glomerulonephritis, the levels of MMP-3 and TIMP-2 were increased. On the other hand, the levels of type IV collagen, MMP-2 and TIMP-1 were increased in patients with membranous nephropathy in which the thickening of basement membrane is characteristic. These differences may be caused by the difference of the pathogenesis of these diseases. The present results suggest that the imbalance between the metabolism of ECMs occurs in patients with glomerulonephritis and contributes to the progression of glomerulonephritis.


Assuntos
Colágeno/sangue , Glomerulonefrite/sangue , Metaloendopeptidases/sangue , Inibidores de Proteases/sangue , Proteínas/metabolismo , Adulto , Clonagem Molecular , Matriz Extracelular/metabolismo , Feminino , Glomerulonefrite/enzimologia , Glomerulonefrite/metabolismo , Glicoproteínas/sangue , Homeostase , Humanos , Técnicas Imunoenzimáticas , Glomérulos Renais/enzimologia , Glomérulos Renais/metabolismo , Masculino , Pessoa de Meia-Idade , Inibidor Tecidual de Metaloproteinase-2 , Inibidores Teciduais de Metaloproteinases
20.
Nephron ; 79(1): 91-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9609468

RESUMO

Mononuclear cells, primarily macrophages and lymphocytes, infiltrate the renal glomeruli and are involved in the progression of various glomerular diseases. Intercellular adhesion molecule 1 (ICAM-1) is expressed on the vascular endothelium and mediates the infiltration of leukocytes into the site of inflammation. Although the expression of ICAM-1 can be induced by the stimulation of inflammatory cytokine, ICAM-1 expression can also be induced by such nonimmune mechanisms as shear stress. Glomerular hyperfiltration is a major mechanism that contributes to the progression of the glomerular sclerosis that results from the loss of functioning nephrons. In the present study, we examined the role of ICAM-1 for mononuclear cell infiltration in the glomeruli of the five-sixth nephrectomized rat as a model of glomerular hyperfiltration. The fluorescence intensity score of the staining for ICAM-1 in the glomeruli of the five-sixth nephrectomized rats was significantly increased as compared with that in the control (sham-operated) rats at 1 week (1.51 +/- 0.15 vs. 0.61 +/- 0.13; p < 0.01) and 2 weeks (1.31 +/- 0.17 vs. 0.51 +/- 0.09; p < 0.01). The number of leukocytes present in the glomeruli was significantly increased in the five-sixth nephrectomized rats compared with control (sham-operated) rats at 1 week (3.44 +/- 0.16 vs. 0.99 +/- 0.08; p < 0.01) and 2 weeks (3.14 +/- 0.14 vs. 0.89 +/- 0.07; p < 0.01). Leukocytes mainly consisted of macrophages in the five-sixth nephrectomized rats at 1 week (2.39 +/- 0.19) and 2 weeks (1.46 +/- 0.11). Anti-ICAM-1 monoclonal antibody effectively prevented the infiltration of macrophages into the glomeruli following nephrectomy. These results indicate that glomerular hyperfiltration may be involved in the induction of the expression of ICAM-1 and the infiltration of macrophages into the renal glomeruli following glomerular injury.


Assuntos
Molécula 1 de Adesão Intercelular/fisiologia , Glomérulos Renais/fisiopatologia , Leucócitos Mononucleares/metabolismo , Nefrectomia/efeitos adversos , Animais , Anticorpos Monoclonais/farmacologia , Antígenos CD/imunologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/genética , Imuno-Histoquímica , Macrófagos/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
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