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1.
Phys Rev Lett ; 118(5): 052701, 2017 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-28211732

RESUMEN

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.
Diabetologia ; 48(11): 2402-11, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16231067

RESUMEN

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.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Diabetes Mellitus Experimental/complicaciones , Nefropatías Diabéticas/prevención & control , Eritromicina/farmacología , Riñón/efectos de los fármacos , Albuminuria/tratamiento farmacológico , Animales , Quimiocina CCL2/efectos de los fármacos , Quimiocina CCL2/genética , Colágeno Tipo IV/efectos de los fármacos , Colágeno Tipo IV/genética , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/patología , Molécula 1 de Adhesión Intercelular/metabolismo , Riñón/patología , Riñón/fisiología , Macrófagos/efectos de los fármacos , FN-kappa B/efectos de los fármacos , FN-kappa B/metabolismo , Ratas , Ratas Sprague-Dawley , Estreptozocina/toxicidad , Factor de Transcripción ReIA/efectos de los fármacos , Factor de Transcripción ReIA/metabolismo , Factor de Crecimiento Transformador beta/efectos de los fármacos , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta1
3.
J Chromatogr A ; 930(1-2): 165-9, 2001 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-11681574

RESUMEN

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.


Asunto(s)
Electroforesis Capilar/instrumentación , Mediciones Luminiscentes
4.
Diabetes Res Clin Pract ; 53(3): 149-59, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11483230

RESUMEN

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.


Asunto(s)
Albuminuria , Diabetes Mellitus Tipo 2/fisiopatología , Tasa de Filtración Glomerular/fisiología , Óxido Nítrico/fisiología , Adulto , Factores de Edad , Anciano , Animales , Glucemia/metabolismo , Presión Sanguínea , Creatinina/sangre , Creatinina/orina , Estudios Transversales , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/orina , Dihidrolipoamida Deshidrogenasa/análisis , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Hemoglobina Glucada/análisis , Humanos , Glomérulos Renales/enzimología , Masculino , Persona de Mediana Edad , Nitratos/orina , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo III , Nitritos/orina , Valores de Referencia
5.
Nephron ; 83(2): 160-4, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10516496

RESUMEN

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.


Asunto(s)
Neoplasias Pulmonares/complicaciones , Síndrome Nefrótico/etiología , Síndrome Nefrótico/radioterapia , Anciano , Edema/radioterapia , Glomerulonefritis Membranosa/diagnóstico por imagen , Glomerulonefritis Membranosa/etiología , Glomerulonefritis Membranosa/radioterapia , Humanos , Riñón/patología , Neoplasias Pulmonares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Síndrome Nefrótico/diagnóstico por imagen , Síndromes Paraneoplásicos/radioterapia , Proteinuria/etiología , Proteinuria/patología , Proteinuria/radioterapia , Tomografía Computarizada por Rayos X
6.
Biochem Biophys Res Commun ; 261(3): 820-3, 1999 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-10441508

RESUMEN

Previously, we reported that the formation of focal adhesion accelerated by accumulation of extracellular matrices may inhibit the angiotensin II-stimulated proliferation of human mesangial cells (HMCs). The process is regulated by p44/42 MAP kinase activity through the mediation of paxillin and GTPase activating proteins. In this report, we investigated the effect of integrin molecules on the angiotensin II-induced p44/42 MAP kinase activation in non-adherent HMCs. The results demonstrated that incubation of cells with both antibody to integrin beta(1) chain (K20) and GRGDS peptide induced integrin clustering, paxillin aggregation, and marked suppression of angiotensin II-induced p44/42 MAP kinase activation. On the other hand, incubation of cells with K20 alone induced integrin clustering without paxillin aggregation and the suppressive effect on angiotensin II-stimulated p44/42 MAP kinase activity. Our results strongly suggest the pivotal role of integrins in the inhibitory effect of focal adhesion on p44/42 MAP kinase activity, the checking system against angiotensin II-induced MAP kinase overactivation.


Asunto(s)
Angiotensina II/farmacología , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Adhesión Celular/fisiología , Mesangio Glomerular/enzimología , Integrinas/fisiología , Proteínas Quinasas Activadas por Mitógenos , Anticuerpos/farmacología , Antígenos CD/metabolismo , Moléculas de Adhesión Celular/metabolismo , Células Cultivadas , Proteínas del Citoesqueleto/metabolismo , Activación Enzimática/efectos de los fármacos , GTP Fosfohidrolasas/metabolismo , Humanos , Integrina alfa5 , Integrina beta1/inmunología , Integrina beta1/fisiología , Proteína Quinasa 3 Activada por Mitógenos , Paxillin , Fosfoproteínas/metabolismo
7.
Biochem Biophys Res Commun ; 257(1): 234-8, 1999 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-10092539

RESUMEN

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.


Asunto(s)
Angiotensina II/farmacología , Adhesión Celular/efectos de los fármacos , Mesangio Glomerular/metabolismo , Factores de Intercambio de Guanina Nucleótido , Proteínas/metabolismo , Transducción de Señal/efectos de los fármacos , Adhesión Celular/fisiología , Moléculas de Adhesión Celular/metabolismo , Células Cultivadas , Proteínas del Citoesqueleto/metabolismo , Activación Enzimática/efectos de los fármacos , Matriz Extracelular/metabolismo , Quinasa 1 de Adhesión Focal , Proteína-Tirosina Quinasas de Adhesión Focal , Proteínas Activadoras de GTPasa , Mesangio Glomerular/citología , Mesangio Glomerular/efectos de los fármacos , Mesangio Glomerular/enzimología , Humanos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteínas Nucleares/metabolismo , Paxillin , Fosfoproteínas/metabolismo , Fosforilación/efectos de los fármacos , Fosfotirosina/metabolismo , Pruebas de Precipitina , Unión Proteica/efectos de los fármacos , Proteínas Tirosina Quinasas/metabolismo , Proteínas Represoras
8.
Nephron ; 81(3): 264-70, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10050079

RESUMEN

Upper respiratory tract infection including chronic tonsillitis is considered to be involved in the onset and/or the progression of IgA nephropathy. It is well known that deterioration of urinary findings occurs after episodes of upper respiratory tract infection in patients with IgA nephropathy. We previously showed that the expression of macrophage-colony-stimulating factor (M-CSF) is increased in the glomeruli of patients with IgA nephropathy and correlated with glomerular mesangial proliferation, suggesting that M-CSF plays an important role in the progression of IgA nephropathy. In the present study, we measured the serum and urinary concentrations of M-CSF in patients with IgA nephropathy associated with chronic tonsillitis. Furthermore, we evaluated the effects of the local provocation test of tonsils (mechanical tonsil stimulation) on the serum and urinary concentrations of M-CSF in the following three groups: (1) IgA nephropathy with severe mesangial proliferation, (2) IgA nephropathy with mild mesangial proliferation, and (3) patients with chronic tonsillitis without renal disease. The serum and urinary levels of M-CSF in the groups with severe and mild IgA nephropathy were significantly higher than those in the chronic tonsillitis group. The urinary M-CSF level but not the serum M-CSF level was positively correlated with the degrees of mesangial proliferation and glomerular M-CSF expression in the renal biopsy specimens. The urinary M-CSF concentration was significantly increased after tonsillitis stimulation in both mild and severe IgA nephropathy groups. Enhanced urinary excretion of M-CSF prolonged for 7 days after tonsil stimulation in the severe IgA nephropathy group; in contrast, the urinay M-CSF level was increased for only 2 days after tonsil stimulation in the mild IgA nephropathy group. The urinary M-CSF level was not changed in the chronic tonsillitis group after tonsil stimulation. The serum concentrations of M-CSF were not changed after tonsil stimulation in these three groups. Our present results suggest that tonsil stimulation contributes to the progression of IgA nephropathy via enhancement of glomerular production of M-CSF. The urinary excretion of M-CSF may be a useful predictor to evaluate the relevance of chronic tonsillitis to the disease and the indication of tonsillectomy in patients with IgA nephropathy.


Asunto(s)
Glomerulonefritis por IGA/complicaciones , Glomerulonefritis por IGA/orina , Factor Estimulante de Colonias de Macrófagos/orina , Tonsila Palatina/fisiopatología , Tonsilitis/complicaciones , Adulto , Estudios de Casos y Controles , Femenino , Mesangio Glomerular/metabolismo , Glomerulonefritis por IGA/fisiopatología , Humanos , Factor Estimulante de Colonias de Macrófagos/sangre , Factor Estimulante de Colonias de Macrófagos/metabolismo , Masculino , Persona de Mediana Edad , Estimulación Física , Tonsilitis/fisiopatología
9.
Nephron ; 80(4): 408-13, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9832639

RESUMEN

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.


Asunto(s)
Proteínas Portadoras/metabolismo , Proteínas Portadoras/fisiología , Activación de Complemento/fisiología , Glomerulonefritis por IGA/metabolismo , Glomérulos Renales/metabolismo , Adulto , División Celular/fisiología , Colectinas , Complemento C2/metabolismo , Complemento C2/fisiología , Complemento C4/metabolismo , Complemento C4/fisiología , Glomerulonefritis por IGA/sangre , Glomerulonefritis por IGA/patología , Humanos , Inmunohistoquímica , Glomérulos Renales/patología , Persona de Mediana Edad
10.
Biosci Biotechnol Biochem ; 62(6): 1211-5, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9692206

RESUMEN

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.


Asunto(s)
Isomerasas de Aminoácido/química , Poliaminas/análisis , Venenos de Araña/análisis , Aminopiridinas , Conformación de Carbohidratos , Secuencia de Carbohidratos , Cromatografía Líquida de Alta Presión , Datos de Secuencia Molecular
11.
Nephron ; 79(1): 91-8, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9609468

RESUMEN

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.


Asunto(s)
Molécula 1 de Adhesión Intercelular/fisiología , Glomérulos Renales/fisiopatología , Leucocitos Mononucleares/metabolismo , Nefrectomía/efectos adversos , Animales , Anticuerpos Monoclonales/farmacología , Antígenos CD/inmunología , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/genética , Inmunohistoquímica , Macrófagos/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley
12.
Kidney Int ; 53(5): 1314-20, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9573547

RESUMEN

Prostacyclin (PGI2) is known to have a relaxative action on vascular smooth muscle, an inhibitory action against platelet activation and neutrophil function. Previous studies showed the preventive effects of PGI2 on lupus nephritis and Thy-1 nephritis, although the mechanism has not been clarified. Glomerular endothelial expression of intercellular adhesion molecule-1 (ICAM-1) is up-regulated in experimental and human glomerular diseases, and is known to facilitate leukocyte infiltration into the glomeruli, which ultimately induces the various glomerular injuries. In the present study, we evaluated the therapeutic effects of PGI2 on a rat model for crescentic glomerulonephritis and investigated its putative mechanism in relation to ICAM-1-mediated leukocyte recruitment. Wistar-Kyoto (WKY) rats were injected with nephrotoxic serum and received continuous intraperitoneal infusion of PGI2. PGI2 dramatically decreased proteinuria (123.0 +/- 18.8 vs. 31.6 +/- 4.5), crescent formation and deposition of fibrinogen in the glomeruli, while the deposition of rabbit IgG, rat IgG and rat C3 along the capillary walls was not changed. Furthermore, intraglomerular expression of ICAM-1 and infiltration of macrophages were significantly suppressed by administration with PGI2. In contrast, influx of CD4 or CD8 positive cells was not altered. The present results suggest that PGI2 shows the preventive effects on experimental crescentic glomerulonephritis by inhibiting intraglomerular coagulation and ICAM-1-mediated macrophage-glomerular endothelial cell adhesive pathway.


Asunto(s)
Epoprostenol/análogos & derivados , Glomerulonefritis/tratamiento farmacológico , Prostaglandinas Sintéticas/uso terapéutico , Animales , Epoprostenol/uso terapéutico , Glomerulonefritis/inmunología , Glomerulonefritis/patología , Humanos , Inmunohistoquímica , Molécula 1 de Adhesión Intercelular/metabolismo , Glomérulos Renales/inmunología , Glomérulos Renales/patología , Macrófagos/inmunología , Macrófagos/patología , Masculino , Conejos , Ratas , Ratas Endogámicas WKY
13.
Diabetes ; 46(12): 2075-81, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9392499

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Molécula 1 de Adhesión Intercelular/metabolismo , Glomérulos Renales/metabolismo , Aldehído Reductasa/antagonistas & inhibidores , Animales , Anticuerpos Monoclonales/farmacología , Células Cultivadas , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/patología , Endotelio Vascular/metabolismo , Inhibidores Enzimáticos/farmacología , Humanos , Inmunohistoquímica , Insulina/uso terapéutico , Molécula 1 de Adhesión Intercelular/inmunología , Glomérulos Renales/patología , Linfocitos/patología , Macrófagos/patología , Masculino , Monocitos/patología , Nefrectomía , Ratas , Ratas Sprague-Dawley , Venas Umbilicales
14.
Res Commun Mol Pathol Pharmacol ; 95(2): 115-28, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9090749

RESUMEN

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.


Asunto(s)
Colágeno/sangre , Glomerulonefritis/sangre , Metaloendopeptidasas/sangre , Inhibidores de Proteasas/sangre , Proteínas/metabolismo , Adulto , Clonación Molecular , Matriz Extracelular/metabolismo , Femenino , Glomerulonefritis/enzimología , Glomerulonefritis/metabolismo , Glicoproteínas/sangre , Homeostasis , Humanos , Técnicas para Inmunoenzimas , Glomérulos Renales/enzimología , Glomérulos Renales/metabolismo , Masculino , Persona de Mediana Edad , Inhibidor Tisular de Metaloproteinasa-2 , Inhibidores Tisulares de Metaloproteinasas
16.
Drug Metab Dispos ; 24(11): 1186-91, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8937851

RESUMEN

We previously showed that a polymorphism for E6123 [(S)-(+)-6- (2-chlorophenyl)-3-cyclopropanecarbonyl-8,11-dimethyl-2,3,4,5- tetrahydro-8H-pyrido[4',3':4,5]thieno[3,2-f][1,2,4]triazolo[4,3-a] [1,4]diazepine] metabolism exists only in rhesus monkeys. In the present study, we purified, from rhesus monkey hepatic microsomes, three amido hydrolases that are involved in the metabolic polymorphism. Two forms of amido hydrolase from an extensive metabolizer and one from a poor metabolizer were purified by Q-Sepharose Fast Flow, Red A-agarose, octylamino-Sepharose 4B, and hydroxyapatite-Ultrogel chromatography, after solubilization with Lubrol. The three purified enzymes had the same molecular mass (47 kDa), and their amino-terminal amino acid sequences were identical. The enzymes were different from various known carboxylesterases in terms of substrate specificity, molecular mass, and amino-terminal amino acid sequence. They resembled arylacetamide deacetylase from human hepatic microsomes with respect to molecular mass and amino-terminal amino acid sequence. The KM values of the high and low affinity enzymes in the extensive metabolizer and the sole enzyme in the poor metabolizer were 37.6, 73.0, and 76.5 microM, respectively. The Vmax values were 3312.4, 504.8, and 427.9 pmol/min/mg of protein, respectively. The high affinity enzyme in extensive metabolizer appears to be quite distinct, whereas the low affinity enzyme in extensive metabolizer in similar or identical to the sole enzyme in poor metabolizer. Thus, the metabolic polymorphism in rhesus monkey may depend upon the existence of the high affinity enzyme in extensive metabolizer.


Asunto(s)
Amidohidrolasas/aislamiento & purificación , Azepinas/farmacología , Hígado/enzimología , Glicoproteínas de Membrana Plaquetaria/antagonistas & inhibidores , Polimorfismo Genético , Receptores de Superficie Celular , Receptores Acoplados a Proteínas G , Triazoles/farmacología , Amidohidrolasas/genética , Amidohidrolasas/metabolismo , Secuencia de Aminoácidos , Animales , Cromatografía Liquida , Electroforesis en Gel de Poliacrilamida , Macaca mulatta , Masculino , Datos de Secuencia Molecular , Peso Molecular , Homología de Secuencia de Aminoácido , Especificidad por Sustrato
17.
Biophys Chem ; 61(2-3): 63-72, 1996 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-8956480

RESUMEN

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.


Asunto(s)
Actinas/metabolismo , Adenosina Trifosfato/metabolismo , Guanosina Trifosfato/metabolismo , Subfragmentos de Miosina/metabolismo , Animales , Guanosina 5'-O-(3-Tiotrifosfato)/farmacología , Guanosina Difosfato/farmacología , Cinética , Músculo Esquelético/metabolismo , Unión Proteica , Conejos
18.
J Biol Chem ; 270(28): 16719-23, 1995 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-7622482

RESUMEN

A novel peptide isomerase was purified from the venom of funnel web spider, Agelenopsis aperta. The complete primary structure of the isomerase has been established by sequence analyses of polypeptide chains, assignments of disulfide bridges, carbohydrate analyses, and mass spectrometry of sugar chains. The isomerase was found to be a 29-kDa polypeptide that consists of an 18-residue light chain and a 243-residue heavy chain connected by a single disulfide bridge. The heavy chain contains three intramolecular disulfide bridges and one N-linked oligosaccharide chain with a simple trimannosyl core structure. A sequence homology search showed a significant similarity of the enzyme with serine proteases, particularly around a putative catalytic triad of the isomerase. The isomerase specifically interconverts the configuration of Ser46 of a 48-amino-acid peptide, omega-agatoxin-TK, and the conversion rate from L-Ser to D-Ser was approximately two times faster than the reverse reaction.


Asunto(s)
Isomerasas de Aminoácido/química , Péptidos/metabolismo , Venenos de Araña/análisis , Isomerasas de Aminoácido/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Secuencia de Carbohidratos , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Serina Endopeptidasas/química , Arañas
19.
Respir Med ; 89(4): 271-8, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7597266

RESUMEN

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.


Asunto(s)
Neumonía/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fibrina , Fibroblastos/patología , Humanos , Masculino , Persona de Mediana Edad , Neumonía/diagnóstico , Neumonía/tratamiento farmacológico , Prednisolona/uso terapéutico , Pronóstico , Alveolos Pulmonares/patología
20.
Nihon Kyobu Shikkan Gakkai Zasshi ; 32(6): 550-4, 1994 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-8089942

RESUMEN

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.


Asunto(s)
Enfermedades Pulmonares Intersticiales/diagnóstico , Actinas/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Autoanticuerpos/análisis , Bronquiolitis Obliterante/diagnóstico , Bronquiolitis Obliterante/inmunología , Femenino , Fibrina/análisis , Humanos , Inmunohistoquímica , Enfermedades Pulmonares Intersticiales/inmunología , Masculino , Persona de Mediana Edad , Pronóstico
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