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1.
Am J Transplant ; 12 Suppl 4: S9-17, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22974463

RESUMO

Clinical evidence suggests that recurrent acute cellular rejection (ACR) may trigger chronic rejection and impair outcome after intestinal transplantation. To test this hypothesis and clarify underlying molecular mechanisms, orthotopic/allogenic intestinal transplantation was performed in rats. ACR was allowed to occur in a MHC-disparate combination (BN-LEW) and two rescue strategies (FK506monotherapy vs. FK506+infliximab) were tested against continuous immunosuppression without ACR, with observation for 7/14 and 21 days after transplantation. Both, FK506 and FK506+infliximab rescue therapy reversed ACR and resulted in improved histology and less cellular infiltration. Proinflammatory cytokines and chemotactic mediators in the muscle layer were significantly reduced in FK506 treated groups. Increased levels of CD4, FOXP3 and IL-17 (mRNA) were observed with infliximab. Contractile function improved significantly after FK506 rescue therapy, with a slight benefit from additional infliximab, but did not reach nontransplanted controls. Fibrosis onset was detected in both rescue groups by Sirius-Red staining with concomitant increase of the fibrogenic mediator VEGF. Recovery from ACR could be attained by both rescue therapy regimens, progressing steadily after initiation of immunosuppression. Reversal of ACR, however, resulted in early stage graft fibrosis. Additional infliximab treatment may enhance physiological recovery of the muscle layer and enteric nervous system independent of inflammatory reactions.


Assuntos
Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Imunossupressores/uso terapêutico , Intestino Delgado/fisiologia , Intestino Delgado/transplante , Transplante de Órgãos/fisiologia , Regeneração/fisiologia , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Citocinas/metabolismo , Quimioterapia Combinada , Fibrose , Imunossupressores/farmacologia , Infliximab , Intestino Delgado/patologia , Macrófagos/patologia , Masculino , Modelos Animais , Neutrófilos/patologia , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Regeneração/efeitos dos fármacos , Tacrolimo/farmacologia , Tacrolimo/uso terapêutico , Transplante Homólogo , Fator de Necrose Tumoral alfa/antagonistas & inibidores
2.
Langenbecks Arch Surg ; 397(1): 131-40, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21960137

RESUMO

PURPOSE: Ischemia-reperfusion injury leads to impaired smooth muscle function and inflammatory reactions after intestinal transplantation. In previous studies, infliximab has been shown to effectively protect allogenic intestinal grafts in the early phase after transplantation with resulting improved contractility. This study was designed to reveal protective effects of infliximab on ischemia-reperfusion injury in isogenic transplantation. METHODS: Isogenic, orthotopic small bowel transplantation was performed in Lewis rats (3 h cold ischemia). Five groups were defined: non-transplanted animals with no treatment (group 1), isogenic transplanted animals with vehicle treatment (groups 2/3) or with infliximab treatment (5 mg/kg body weight intravenously, directly after reperfusion; groups 4/5). The treated animals were sacrificed after 3 (group 2/4) or 24 h (group 3/5). Histological and immunohistochemical analysis, TUNEL staining, real-time RT-PCR, and contractility measurements in a standard organ bath were used for determination of ischemia-reperfusion injury. RESULTS: All transplanted animals showed reduced smooth muscle function, while no significant advantage of infliximab treatment was observed. Reduced infiltration of neutrophils was noted in the early phase in animals treated with infliximab. The structural integrity of the bowel and infiltration of ED1-positive monocytes and macrophages did not improve with infliximab treatment. At 3 h after reperfusion, mRNA expression of interleukin (IL)-6, TNF-α, IL-10, and iNOS and MCP-1 displayed increased activation in the infliximab group. CONCLUSION: The protective effects of infliximab in the early phase after experimental small bowel transplantation seem to be unrelated to ischemia-reperfusion injury. The promising effects in allogenic transplantation indicate the need for further experiments with infliximab as complementary treatment under standard immunosuppressive therapy. Further experiments should focus on additional infliximab treatment in the setting of acute rejection.


Assuntos
Anti-Inflamatórios/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Intestino Delgado/transplante , Traumatismo por Reperfusão/prevenção & controle , Animais , Apoptose , Técnicas In Vitro , Infliximab , Intestino Delgado/irrigação sanguínea , Intestino Delgado/patologia , Intestino Delgado/fisiopatologia , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/patologia , Ratos , Ratos Endogâmicos Lew , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Transplante Isogênico
3.
Lupus ; 20(13): 1378-86, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21893562

RESUMO

The objective of the present study was to elucidate the association between glomerular complement depositions belonging to the alternative (AP) and lectin (LP) pathways, and clinical findings of lupus nephritis (LN). Immunofluorescence (IF) was performed on 17 LN patients using antibodies against factor B, factor H, properdin, mannose-binding lectin (MBL) and L-ficolin. Compared with factor B/factor H negative patients (n = 9), positive patients (n = 8) showed longer duration of LN (p < 0.05) and more severe interstitial fibrosis (p < 0.05). Eleven patients had properdin deposition in glomeruli, and in three of them, with a duration of LN of less than 1 month, factor B was undetectable. Compared with properdin negative patients (n = 6), positive patients (n = 11) showed significantly higher urinary protein excretion (p < 0.01). MBL/L-ficolin positive patients (n = 11) also had significantly higher urinary protein excretion (p < 0.05) compared with negative patients (n = 6). An independent association was found between glomerular deposition of properdin and that of MBL/L-ficolin (p < 0.01) in addition to factor B/factor H. Traces of glomerular activation of AP and LP reflected the clinical status of LN. It appears that glomerular deposition of each complement component, especially properdin, may be an index of the histological activity of LN.


Assuntos
Via Alternativa do Complemento/imunologia , Lectina de Ligação a Manose da Via do Complemento/imunologia , Glomérulos Renais/imunologia , Nefrite Lúpica/imunologia , Adulto , Fator B do Complemento/imunologia , Fator H do Complemento/imunologia , Fibrose , Humanos , Glomérulos Renais/patologia , Lectinas/imunologia , Nefrite Lúpica/patologia , Nefrite Lúpica/fisiopatologia , Masculino , Lectina de Ligação a Manose/imunologia , Pessoa de Meia-Idade , Properdina/imunologia , Proteinúria/imunologia , Adulto Jovem , Ficolinas
4.
Am J Transplant ; 10(11): 2431-41, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20977634

RESUMO

As we have shown in the past, acute rejection-related TNF-α upregulation in resident macrophages in the tunica muscularis after small bowel transplantation (SBTx) results in local amplification of inflammation, decisively contributing to graft dysmotility. Therefore, the aim of this study is to investigate the effectiveness of the chimeric-monoclonal-anti-TNF-α antibody infliximab as perioperative single shot treatment addressing inflammatory processes during acute rejection early after transplantation. Orthotopic, isogenic and allogenic SBTx was performed in rats (BN-Lewis/BN-BN) with infliximab treatment. Vehicle and IV-immunoglobulin-treated animals served as controls. Animals were sacrificed after 24 and 168 h. Leukocyte infiltration was investigated in muscularis whole mounts by immunohistochemistry, mediator mRNA expression by Real-Time-RT-PCR, apoptosis by TUNEL and smooth muscle contractility in a standard organ bath. Both, infliximab and Sandoglobulin® revealed antiinflammatory effects. Infliximab resulted in significantly less leukocyte infiltration compared to allogenic controls and IV-immunoglobulin, which was accompanied by lower gene expression of MCP-1 (24 h), IFN-γ (168 h) and infiltration of CD8-positive cells. Smooth muscle contractility improved significantly after 24 h compared to all controls in infliximab treated animals accompanied by lower iNOS expression. Perioperative treatment with infliximab is a possible pharmaceutical approach to overcome graft dysmotility early after SBTx.


Assuntos
Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Inflamação/prevenção & controle , Intestino Delgado/transplante , Animais , Apoptose , Betanecol/farmacologia , Motilidade Gastrointestinal , Imunoglobulinas Intravenosas/uso terapêutico , Infliximab , Interleucina-10/biossíntese , Interleucina-1beta/biossíntese , Infiltração de Neutrófilos , Óxido Nítrico Sintase Tipo II/biossíntese , Assistência Perioperatória , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Transplante Homólogo/imunologia , Transplante Isogênico/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/imunologia
5.
Clin Nephrol ; 73(2): 157-62, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20129024

RESUMO

Type B insulin resistance syndrome is a rare disease. Auto-antibodies to the insulin receptor frequently appear in the case of systemic lupus erythematosus (SLE). We report herein a case of a 56-year-old man who had presented discoid skin lesions since 1990. He was admitted to the hospital because of unconsciousness and severe hypoglycemia in 2006, and was diagnosed as having Type B insulin resistance syndrome with the presence of insulin receptor antibody. He had frequently repeated hypoglycemic and hyperglycemic episodes in spite of treatment with prednisolone (5 - 10 mg/day), and mild proteinuria of 1.5 g/day was observed. His laboratory findings on admission revealed pancytopenia and positive titer for antinuclear antibody (ANA). From these findings and his past history of skin lesions, we diagnosed him as SLE. We performed renal biopsy and his histological diagnosis was lupus nephritis Class 5 with the findings of podocytic shedding. Prednisolone dosage was increased from 10 to 60 mg/day. Thereafter, his glucose metabolism improved and proteinuria disappeared. The dose of prednisolone was tapered to 30 mg/day without recurrence of hypoglycemia and proteinuria. Early treatment with prednisolone might ameliorate proteinuria and insulin resistance. We experienced a rare case of Type B insulin resistance syndrome with increased activity of SLE, complicated with lupus nephritis. It appears that Type B insulin resistance syndrome should be suspected in differential diagnosis of hypoglycemia in SLE patients.


Assuntos
Resistência à Insulina , Insulina/sangue , Lúpus Eritematoso Sistêmico/complicações , Síndrome Metabólica/etiologia , Biópsia , Relação Dose-Resposta a Droga , Seguimentos , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Humanos , Rim/patologia , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/tratamento farmacológico , Microscopia Eletrônica , Pessoa de Meia-Idade , Prednisolona/administração & dosagem , Prednisolona/uso terapêutico , Receptor de Insulina/imunologia
6.
Clin Nephrol ; 68(2): 121-4, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17722713

RESUMO

A 57-year-old-woman, who was treated with regular maintenance hemodialysis (HD), newly contracted rheumatoid arthritis (RA). Oral predonisolone was effective for alleviating her arthralgia but the RA activity became steroid-dependent. For treatment of poorly controlled synovitis leukocytapheresis (LCAP) showed excellent efficacy in the treatment of her joint pain. No serious adverse effects were observed. Serological markers such as CRP, serum amyloid A, matrix metalloproteinase 3 and peripheral blood lymphocyte count fluctuated with her clinical symptoms. We recommend LCAP as candidate therapy for steroid-dependent patients with RA who are on maintenance HD.


Assuntos
Artrite Reumatoide/terapia , Leucaférese , Diálise Renal , Feminino , Humanos , Pessoa de Meia-Idade
7.
Biochim Biophys Acta ; 962(3): 377-83, 1988 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-3167088

RESUMO

Human serum carboxylesterase (EC 3.1.1.1), purified by affinity chromatography on trimethylammonium anilinium-Sepharose, hydrolyzed the short-chain fatty acid ester tributyrin (40 mumol/mg protein per h), but scarcely hydrolyzed the long-chain fatty acid ester triolein (less than 0.2 mumol/mg protein per h). Phospholipids enhanced triolein hydrolysis by carboxylesterase to various extents, cardiolipin causing the most enhancement (2.5 mumol/mg protein per h). Phosphatidylserine and phosphatidylinositol also enhanced carboxylesterase-catalyzed hydrolysis of triolein (450-980 nmol/mg protein per h). The optimal pH for tributyrin hydrolysis was pH 8.0, but the pH range for triolein hydrolysis was broad, being pH 4.5-7.5. The rates of hydrolyses of monoolein, diolein and triolein by carboxylesterase in the absence and presence of 100 micrograms/ml cardiolipin were 3.9, 0.5 and 0.2 mumol/mg esterase per h and 2.0, 0.6 and 4.0 mumol/mg protein per h, respectively. Thus, on addition of cardiolipin, triolein hydrolysis was enhanced, but tributyrin hydrolysis was reciprocally decreased. Triton X-100 (0.1%) and NaCl (1.0 M) decreased triolein hydrolysis, but did not decrease tributyrin hydrolysis. Mercaptoethanol decreased triolein hydrolysis, but not tributyrin hydrolysis. These results suggest that cardiolipin modifies the interaction of carboxylesterase with substrates in such a way as to facilitate its interaction with a hydrophobic substrate, and that disulfide bonding might be involved in the substrate recognition site.


Assuntos
Hidrolases de Éster Carboxílico/sangue , Fosfolipídeos/farmacologia , Trioleína/metabolismo , Carboxilesterase , Hidrolases de Éster Carboxílico/metabolismo , Cardiolipinas/farmacologia , Diglicerídeos/metabolismo , Glicerídeos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Mercaptoetanol/farmacologia , Octoxinol , Polietilenoglicóis/farmacologia , Cloreto de Sódio/farmacologia , Triglicerídeos/metabolismo
8.
Gene ; 80(1): 39-48, 1989 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-2507401

RESUMO

Biotin synthetase (BS) catalyses the biotransformation of dethiobiotin (DTB) to biotin. Here we report the cloning, characterization and expression of the gene encoding BS of Bacillus sphaericus. A recombinant plasmid pSB01, containing an 8.2-kb DNA fragment from B. sphaericus, was isolated by phenotypic complementation of an Escherichia coli bioB strain. Nucleotide sequence analysis of this fragment and N-terminal sequence determination of the recombinant protein product revealed that the bioB gene of B. sphaericus consists of a 996-bp open reading frame which is closely associated with at least one other gene. E. coli cells transformed with a bioB expression vector performed efficient bioconversion of DTB to biotin under defined culture conditions. Biotin production from transformed Bacillus subtilis and B. sphaericus recombinant strains was also demonstrated. Comparison of the amino acid sequences of BS from E. coli and B. sphaericus revealed extensive similarity.


Assuntos
Bacillus subtilis/genética , Bacillus/genética , Clonagem Molecular , Escherichia coli/genética , Genes Bacterianos , Sulfurtransferases/genética , Sequência de Aminoácidos , Bacillus/enzimologia , Sequência de Bases , Biotina/biossíntese , DNA Bacteriano/genética , Eletroforese em Gel de Poliacrilamida , Escherichia coli/crescimento & desenvolvimento , Amplificação de Genes , Teste de Complementação Genética , Vetores Genéticos , Dados de Sequência Molecular , Plasmídeos , Homologia de Sequência do Ácido Nucleico , Sulfurtransferases/biossíntese , Transformação Genética
9.
Gene ; 108(1): 39-45, 1991 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-1761229

RESUMO

The genes involved in biotin synthesis have recently been isolated from Bacillus sphaericus [Gloeckler et al., Gene 87 (1990) 63-70]. Sequence analysis revealed that they are organized into two gene clusters, designated bioXWF and bioDAYB. The 5'-noncoding region of the bioD locus fused to the xylE reporter gene was inserted into the Gram-positive pUB110 replicon and the resulting plasmid was introduced into B. sphaericus IFO3525. Transformants expressed the xylE gene only if the biotin concentration in the growth medium remained below 50 ng/ml. After mutagenesis, colonies were screened for their ability to express the chromogenic marker in the presence of an excess of biotin. Most of these mutants escaped biotin repression of xylE gene expression. Classical genetic analysis showed they formed two main categories: chromosomal mutations, pleiotropically acting in trans on both bioXWF and bioDAYB 5'-noncoding regions, in which a 15-bp region common to both promoters represented a hot-spot for the second class of plasmid-associated mutations. These results, completed by the identification of transcription start points for the bioD and bioX genes, strongly suggest that this 15-bp sequence overlaps the site of a biotin-mediated negative regulation circuit controlling the transcription of the bio genes.


Assuntos
Bacillus/genética , Biotina/genética , Dioxigenases , Regulação Bacteriana da Expressão Gênica/genética , Sequência de Aminoácidos , Sequência de Bases , Biotina/análise , Biotina/biossíntese , Catecol 2,3-Dioxigenase , Dados de Sequência Molecular , Família Multigênica/genética , Mutação/genética , Oxigenases/genética , Oxigenases/metabolismo , Plasmídeos/genética , Regiões Promotoras Genéticas/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transcrição Gênica/genética
10.
Gene ; 87(1): 63-70, 1990 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2110099

RESUMO

Using 8.8 kb of genetic information from Bacillus sphaericus, it was possible to confer to Escherichia coli bio- strains, including delta bioA-D, bioC-, bioH-, the ability to convert exogenous pimelate into biotin. The bio genes were borne on two recombinant plasmids with inserts of 4.3 kb and 4.5 kb, which had been isolated from a genomic bank of HindIII-digested B. sphaericus DNA, by phenotypic complementation of various E. coli bio mutants. The B. sphaericus bioD and bioA genes were unambiguously identified within the 4.3-kb insert and shown to be closely linked to bioY (coding for a protein with a presently unknown function) and to bioB [Ohsawa et al., Gene 80 (1989) 39-48]. These genes are clustered in the order bioDAYB. The 4.5-kb fragment contains genetic information for three different proteins, the products of bioX, bioW and bioF. Complementation studies using an E. coli bioF mutant and a B. subtilis bio112TG3 strain, revealed that the third ORF of this cluster encodes 7-keto-8-aminopelargonic acid synthetase. A combination of bioW and bioF allows an efficient complementation of E. coli bioC and bioH mutants, provided that pimelate is added to the biotin-depleted growth medium. No function could be identified for the product of bioX. The gene order of this cluster is bioXWF. By sequence analysis, the two cloned DNA fragments were shown to bear overlapping open reading frames and secondary structures at their 3' ends, typical of transcription terminators.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Bacillus/genética , Biotina/análogos & derivados , Genes Bacterianos , Ácidos Pimélicos/metabolismo , Bacillus/metabolismo , Bacillus subtilis/genética , Sequência de Bases , Biotina/biossíntese , Biotransformação , Clonagem Molecular/métodos , DNA Bacteriano/genética , Escherichia coli/genética , Genótipo , Dados de Sequência Molecular , Mutação , Mapeamento por Restrição
11.
Br J Pharmacol ; 123(8): 1483-9, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9605551

RESUMO

1. The effects of secreted forms of beta-amyloid-precursor proteins (APP(S)s) on the intracellular Ca2+ concentration ([Ca2+]i) were investigated in rat cultured hippocampal neurones. APP695S, a secretory form of APP695, attenuated the increase in [Ca2+]i evoked by glutamate. In addition, APP695S itself evoked an increase in [Ca2+]i in 1 or 2 day-cultured hippocampal cells, but not in 7 to 13 day-cultured cells. 2. Eighty-one percent of neurones which were immunocytochemically positive for microtubule-associated protein 2 responded to APP695S with an increase in [Ca2+]i. 3. APP695S induced a transient rise in [Ca2+]i even in the absence of extracellular Ca2+ and produced an elevation in inositol-1,4,5-trisphosphate (IP3) in a concentration-dependent manner from 100 to 500 ng ml(-1). In the presence of extracellular Ca2+, APP695S caused a transient rise in [Ca2+]i followed by a sustained phase at high [Ca2+]i, suggesting Ca2+ entry from the extracellular space. 4. The [Ca2+]i elevation was mimicked by amino terminal peptides of APPs, but not by carboxy terminal peptides. 5. These results taken together suggest that APP695S induces an increase in [Ca2+]i in hippocampal neurones through an IP3-dependent mechanism that changes according to the stage of development.


Assuntos
Precursor de Proteína beta-Amiloide/farmacologia , Cálcio/metabolismo , Hipocampo/metabolismo , Neurônios/metabolismo , Animais , Células Cultivadas , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Imuno-Histoquímica , Inositol 1,4,5-Trifosfato/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/efeitos dos fármacos , Ratos , Ratos Wistar , Proteínas Recombinantes/farmacologia
12.
Am J Kidney Dis ; 35(3): 401-7, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10692265

RESUMO

Henoch-Schönlein purpura nephritis (HSPN) is considered a form of systemic vasculitis of the small blood vessels with immune pathogenesis. In this disorder, the complement system is recognized as an important mechanism of glomerular injury. The aim of this study is to determine whether the lectin pathway, a novel pathway of complement activation, is related to the pathogenesis of HSPN. Renal biopsy material from 10 patients with HSPN was studied immunohistochemically and examined for a clinicopathologic correlation. Serum levels of complement components, including mannose-binding lectin (MBL), and plasma levels of complement activation products were also evaluated in these patients and compared with levels in patients with immunoglobulin A (IgA) nephropathy or mesangial proliferative glomerulonephritis (GN) without IgA deposition (non-IgA GN). Glomerular deposition of components of the pathway, MBL and MBL-associated serine protease (MASP-1), as well as C3b/C3c, C5b-9, and C4-binding protein (C4-bp), was detected in 8 of 10 patients. Although no significant correlation was found between glomerular deposition of MBL/MASP-1 and histological or clinical findings, the biopsies on all patients with MBL/MASP-1 deposits were performed within 20 weeks from the onset of disease. Levels of plasma C4d, the activation fragment of C4, and C4-bp, a soluble regulatory protein of the pathway, were greater in patients with HSPN than in those with non-IgA GN. However, there was no difference in serum MBL levels between the three groups of patients (HSPN, IgA nephropathy, and non-IgA GN). These results suggest that complement activation through the lectin pathway was involved at the onset of HSPN, and this mechanism might be important in the disease pathogenesis.


Assuntos
Ativação do Complemento/fisiologia , Glomerulonefrite Membranoproliferativa/fisiopatologia , Vasculite por IgA/complicações , Lectinas/metabolismo , Nefrite/fisiopatologia , Adolescente , Adulto , Criança , Feminino , Glomerulonefrite Membranoproliferativa/etiologia , Humanos , Glomérulos Renais/patologia , Masculino , Manose/metabolismo , Nefrite/etiologia
13.
Am J Kidney Dis ; 36(1): E3, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10873902

RESUMO

A 44-year-old man developed nephrotic syndrome 9 months after HLA-identical sibling bone marrow transplantation. Membranous changes consisted mainly of alterations of glomeruli, which were interpreted as chronic graft-versus-host disease (GVHD) caused by lodging of the circulating immune complex. In the tubules, a lumpy deposition of IgG and complement breakdown products was distributed along the tubular basement membrane, which coincided with the peculiar deposits ascertained by electron microscopy. These findings suggest that an extraglomerular reaction should be considered in evaluating renal involvement of GVHD.


Assuntos
Complexo Antígeno-Anticorpo/análise , Transplante de Medula Óssea/efeitos adversos , Glomérulos Renais/imunologia , Adulto , Transplante de Medula Óssea/imunologia , Técnica Indireta de Fluorescência para Anticorpo , Glomerulonefrite Membranosa , Doença Enxerto-Hospedeiro/etiologia , Humanos , Túbulos Renais/imunologia , Masculino , Síndrome Nefrótica
14.
Brain Res Mol Brain Res ; 53(1-2): 24-32, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9473570

RESUMO

The secreted form of beta-amyloid precursor protein (sAPP) has been reported to exert various biological activities in cultured neurons. The signal transduction mechanisms underlying these physiological functions of sAPP remain unclear. We now report that treatment of neural cells with the secreted form of APP695 (sAPP695) leads to dose- and time-dependent increase in phosphorylation of the endogenous substrates with a molecular mass of 80, 57 and 43 kDa. Pretreatment of cells with protein kinase C (PKC) inhibitor H-7 reduced phosphorylation of the 80- and 43-kDa proteins in a dose-dependent manner. The effect of sAPP695 on the phosphorylation is mimicked by phorbol 12-myristate-13-acetate (PMA). Downregulation of PKC by prolonged treatment of cells with PMA abolished sAPP695-enhanced phosphorylation of the 80- and 43-kDa proteins, indicating PKC is involved in the sAPP695-enhanced phosphorylation of these proteins in the cells. We also suggest that the 80- and 43-kDa proteins phosphorylated by sAPP695-stimulation are the major PKC substrates myristoylated alanine-rich C-kinase substrate and growth-associated protein-43. Furthermore, we demonstrate that tyrosine phosphorylation of phospholipase Cgamma1 and formation of inositol 1,4,5-trisphosphate were increased by sAPP695-stimulation. These observations suggest that sAPP695 induces the activation of the signaling pathways through a stimulation of phosphoinositide-PKC cascade.


Assuntos
Precursor de Proteína beta-Amiloide/farmacologia , Isoenzimas/metabolismo , Neocórtex/enzimologia , Neurônios/enzimologia , Proteína Quinase C/metabolismo , Fosfolipases Tipo C/metabolismo , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Animais , Células Cultivadas , Citosol/enzimologia , Embrião de Mamíferos , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Cinética , Neocórtex/citologia , Neurônios/citologia , Fosfolipase C gama , Fosforilação , Ratos , Ratos Wistar , Proteínas Recombinantes/farmacologia , Transdução de Sinais
15.
Virchows Arch ; 438(3): 306-11, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11315629

RESUMO

A 24-year-old woman presented with renal insufficiency, macrohematuria, and mild urinary protein. Polyclonal hypergamma-globulinemia, thrombocytosis, increased concentration of serum, and urinary interleukin (IL)-6 all indicated persistent immune activation caused by a Chlamydia trachomatis infection of the fallopian tube. Gynecological treatment with levofloxacin was effective both for the renal symptoms and other immunological parameters. First and second renal biopsy specimens showed an immune-complex glomerulopathy with extensive interstitial infiltration of many types of inflammatory cells, including plasma cells. Thus, we conclude that chlamydial salpingitis must be considered as one causative disease factor for renal involvement by means of its persistent immune activation effects.


Assuntos
Complexo Antígeno-Anticorpo/metabolismo , Infecções por Chlamydia/patologia , Chlamydia trachomatis , Rim/patologia , Salpingite/patologia , Adulto , Infecções por Chlamydia/complicações , Feminino , Glomerulonefrite por IGA/etiologia , Humanos , Interleucina-6/fisiologia , Salpingite/complicações
16.
Metabolism ; 53(1): 22-7, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14681837

RESUMO

The present study was performed to investigate whether nitric oxide synthase (NOS) inhibition influences the increased whole-body insulin action by pioglitazone in high-fructose-fed rats. Male Wistar rats aged 6 weeks were randomly divided into 3 groups and each group was fed one of the following diets for 3 weeks: standard chow diet (control group), high-fructose diet (fructose-fed group), and high-fructose diet plus pioglitazone (pioglitazone-treated group). The control and pioglitazone-treated groups were further divided into 2 subgroups respectively, and some rats of each subgroup were infused the NOS inhibitor, N(G)-monomethyl-l-arginine (L-NMMA), during the euglycemic clamp studies. In vivo insulin action was determined by the 2-step (3 and 30 mU/kg body weight [BW]/min low- and high-dose, respectively) hyperinsulinemic euglycemic clamp procedure in the awake condition. Glucose infusion rate (GIR) was considered as the index of insulin action. Endothelium-type NOS (eNOS) and inducible NOS (iNOS) in skeletal muscle were also measured. At the low-dose clamp, high-fructose feeding produced a marked decrease in GIR compared with the control group. Pioglitazone-treated animals showed a significant increase in GIR, reaching a similar level as the control group. However, the improved GIR was decreased to the level of the fructose-fed group by L-NMMA infusion. The GIR of the control group was not affected by L-NMMA infusion. The same tendency as the low-dose clamp was found at the high-dose clamp. In skeletal muscle, eNOS and iNOS protein content were not affected by high-fructose feeding and/or pioglitazone treatment. These results suggest that NOS inhibition can decrease the improved insulin resistance by pioglitazone in high-fructose-fed rats. Therefore, although NOS protein content is not changed by high-fructose feeding and/or pioglitazone treatment, it could be concluded that nitric oxide (NO) plays an important role in the improvement of insulin action by pioglitazone.


Assuntos
Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Tiazolidinedionas/farmacologia , Animais , Peso Corporal , Carboidratos da Dieta/administração & dosagem , Ingestão de Alimentos , Frutose/administração & dosagem , Glucose/administração & dosagem , Glucose/metabolismo , Técnica Clamp de Glucose , Masculino , Músculo Esquelético/enzimologia , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Pioglitazona , Ratos , Ratos Wistar , ômega-N-Metilarginina/farmacologia
17.
J Appl Physiol (1985) ; 80(6): 1963-7, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8806901

RESUMO

We examined the effects of exercise training initiated before maturation or after maturation on insulin sensitivity and glucose transporter GLUT-4 content in membrane fractions of skeletal muscle. Female Wistar rats (4 wk of age) were divided into sedentary and exercise-trained groups. At 12 wk of age, a subset of the trained animals (Tr) was killed along with a subset of sedentary controls (Sed). One-half of the remaining sedentary animals remained sedentary (Sed-Sed) while the other half began exercise training (Sed-Tr). The remaining rats in the original trained group continued to train (Tr-Tr). Euglycemic clamp (insulin infusion rate at 6 mU.kg body wt-1. min-1) was performed at 4, 12, and 27 wk. After euglycemic clamp in all animals except the 4-wk-old, hindlimb (gastrocnemius and part of quadriceps) muscles were removed for preparation of membrane fractions. In sedentary rats, glucose infusion rate (GIR) during euglycemic clamp was decreased from 15.9 mg.kg-1.min-1 at 4 wk of age to 9.8 mg.kg-1.min-1 at 12 wk of age and 9.1 mg.kg-1.min-1 at 27 wk of age. In exercise-trained rats, the GIR was not significantly decreased by maturation (at 12 wk) and further aging (at 27 wk). Initiation of exercise after maturation restored the GIR at 27 wk of age to the same levels as these for the corresponding exercise-trained rats. GLUT-4 content in plasma and intracellular membrane fractions of hindlimb muscle obtained just after euglycemic clamp showed the same trend as the results of GIR. These results suggest that exercise training prevented the maturation-induced decrease in insulin sensitivity. Improvement of insulin sensitivity caused by exercise training was attributed, at least in part, to the increase in insulin-sensitive GLUT-4 on the plasma membrane in skeletal muscle.


Assuntos
Insulina/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Músculo Esquelético/metabolismo , Condicionamento Físico Animal/fisiologia , Fatores Etários , Animais , Membrana Celular/metabolismo , Feminino , Ratos , Ratos Wistar
18.
Artigo em Inglês | MEDLINE | ID: mdl-11728176

RESUMO

Renal blood flow decreases with the progression of chronic glomerulonephritis (CGN). This disease induces medullary ischemia and further renal dysfunction in patients with chronic renal insufficiency (CRI). Prostacyclin (PGI2), with its vasodilative action, increases renal blood flow (RBF) without increasing glomerular filtration rate (GFR). We therefore examined the possibility that PGI2 would mitigate the progression of renal dysfunction by increasing RBF in patients with CRI. Sixteen patients with progressive renal insufficiency (serum creatinine: 2.14+/-0.89 mg/dl) due to CGN were prospectively chosen for this study. The blood pressure was already under control using calcium channel blockers before and during this study in nine hypertensive patients. In the first 6 months the patients received a low-protein (0.6 g/kg/day) and low-salt (5.0 g/day) diet. In the next 6 months they received 60 microg/day of PGI2 analogue (Beraprost sodium) orally. GFR was determined by 24-hour creatinine clearance, and effective renal plasma flow (ERPF) was determined by 99mTc-MAG3 scintigraphy. Glomerular capillary pressure, the resistance ratio of afferent and efferent arterioles (R(A)/R(E)), and the other hemodynamic parameters from Gomez's estimation equation were determined at the start of this study, just before the administration of Beraprost and at the end of the study. The levels of GFR and ERPF were 34.6+/-12.4 and 140.6+/-52.1 ml/min at the start of this study respectively, and decreased to 28.0+/- 12.0 and 115.6+/-45.3 ml/min after the first 6 months without Beraprost. The levels of GFR and ERPF stayed at 28.1+/-15.7 and 119.2+/-57.6 ml/min after the next 6 months with Beraprost in the same patients. R(A)/R(E) increased in the first 6 months from 7.9+/-3.6 to 10.8+/-8.6, but remained constant during 6 months of Beraprost administration, at 10.5+/-8.0. These data indicate that PGI2 analogue diminishes the vascular resistance of glomerular afferent and efferent arterioles regulating the decrease of renal blood flow without glomerular hyperfiltration, thus mitigating the progression rate of renal dysfunction.


Assuntos
Epoprostenol/análogos & derivados , Epoprostenol/uso terapêutico , Taxa de Filtração Glomerular/efeitos dos fármacos , Falência Renal Crônica/tratamento farmacológico , Circulação Renal/efeitos dos fármacos , Fluxo Plasmático Renal Efetivo/efeitos dos fármacos , Vasodilatadores/uso terapêutico , Creatinina/urina , Progressão da Doença , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/fisiopatologia , Glomérulos Renais/fisiopatologia , Cinética , Masculino , Pessoa de Meia-Idade
19.
Diabetes Res Clin Pract ; 22(1): 3-9, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8137714

RESUMO

To evaluate the effects of glimepiride on insulin action in peripheral tissues, we investigated insulin-induced glucose uptake in normal and diabetic rats using the euglycemic clamp procedure (insulin infusion rates: 6 and 30 mU/kg/min). Normal rats: After oral administration of glimepiride (0.1 mg/kg/day; NG) or saline (NC) for 2 weeks, euglycemic clamp procedures were performed. During submaximal hyperinsulinemia (620 +/- 35 pmol/l, mean +/- S.E.M.), metabolic clearance rates of glucose (MCR) in NG were significantly higher than in NC (25.1 +/- 2.1 vs. 18.3 +/- 1.2 ml/kg/min, P < 0.05). During maximal hyperinsulinemia (5235 +/- 270 pmol/l), MCRs in NG were higher than in NC, but there was no statistical significance (43.3 +/- 2.8 and 38.9 +/- 2.8). Diabetic rats: streptozotocin-induced diabetic rats were divided into four groups, GI (glimepiride treatment, 0.1 mg/kg/day p.o., with insulin, 5 U/day s.c.), SI (insulin alone), SG (glimepiride alone), and SC (saline). MCRs in the four groups were similar during 6 mU/kg/min clamps. During 30 mU/kg/min clamps, MCRs in GI were significantly higher than those in SC, SG or SI (23.4 +/- 2.8 vs. 12.2 +/- 1.9 and 8.9 +/- 0.8, P < 0.01, and vs. 17.4 +/- 1.5, P < 0.05). Although MCRs in SI tended to be higher than in SC, there was no significant statistical difference between these two groups. These results suggest that glimepiride enhances insulin action in peripheral tissues, and that glimepiride treatment with insulin improves the insulin resistance observed in streptozotocin-induced diabetic rats.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Compostos de Sulfonilureia/farmacologia , Administração Oral , Animais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Técnica Clamp de Glucose , Hiperinsulinismo/sangue , Infusões Intravenosas , Insulina/administração & dosagem , Insulina/sangue , Masculino , Taxa de Depuração Metabólica , Ratos , Ratos Wistar , Valores de Referência , Compostos de Sulfonilureia/administração & dosagem
20.
Diabetes Res Clin Pract ; 27(2): 141-5, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7607052

RESUMO

To clarify the present state of exercise therapy for diabetes mellitus, we conducted a survey of 570 diabetic outpatients by written questionnaires. The results revealed that approximately 30% of the patients did not implement the prescribed exercise regimen. The principal reasons for low compliance were 'lack of time to do' and 'lack of mind to do'. 'Lack of time to do' was particularly numerous in male patients. Other reasons were 'lack of guidance by physician', 'lack of interest', 'lack of understanding of procedure'. These findings indicated that the patients should be motivated adequately when they are diagnosed as having diabetes and subsequently encouraged to reinforce their intentions by the physician and co-medical staff. Furthermore, they showed that specific approaches suitable for each individual patient and not standardized guidelines should be devised. As regards the daily environment of patients, the cooperation of the patient's family would be effective and the exercise facilities and the exercise guidance personnel should be augmented.


Assuntos
Diabetes Mellitus/psicologia , Diabetes Mellitus/terapia , Terapia por Exercício , Cooperação do Paciente , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Diferenciação Sexual , Fatores Sexuais , Inquéritos e Questionários
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