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1.
J Hosp Infect ; 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32360338

RESUMO

BACKGROUND: Invasive fusariosis (IF) is a frequently fatal disease as there are few antifungals to treat it, making the prevention of IF crucial. However, fusarium infections have not been as thoroughly studied as other common pathogenic fungi such as Aspergillus or Candida. AIM: To investigate the epidemiology of IF in patients with haematological diseases in Japan and to elucidate the infectious route of fusarium infection. METHODS: We retrospectively analysed 29 IF cases in patients with haematological diseases from 2009 to 2019 in Japan. To discover the infectious source of IF, we performed an indoor environment survey targeted at indoor air and drain outlets in medical institutions and residences using culture-based and metagenomic methods. Finally, we performed aerosol- and droplet-mediated dispersion studies. FINDINGS: The epidemiological study showed that the primary pathogen of IF was Fusarium solani species complex (FSSC), and the most common species was Fusarium petroliphilum. Most patients were likely to develop IF during hospitalization. A fusarium culture was positive in 26 of 72 drain samples. Few fusarium were detected from air samples; by contrast, 29 of 108 isolates from the drain outlets were identified as fusarium. Furthermore, similar results were obtained in the metagenomic analysis. Interestingly, species belonging to FSSC were isolated from indoor drain outlets, which was similar to those of the IF patients. In the droplet-mediated dispersion study, eight to 17 colonies of fusarium were isolated. CONCLUSION: Our study indicates that causative Fusarium spp. could inhabit drain outlets in hospitals or residences, and droplet-mediated fusarium dispersion is a potential cause of IF.

2.
Blood Cancer J ; 7(4): e559, 2017 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-28452984

RESUMO

Although tyrosine kinase inhibitors (TKIs) have significantly improved the prognosis of chronic myeloid leukemia (CML), the ability of TKIs to eradicate CML remains uncertain and patients must continue TKI therapy for indefinite periods. In this study, we performed whole-exome sequencing to identify somatic mutations in 24 patients with newly diagnosed chronic phase CML who were registered in the JALSG CML212 study. We identified 191 somatic mutations other than the BCR-ABL1 fusion gene (median 8, range 1-17). Age, hemoglobin concentration and white blood cell counts were correlated with the number of mutations. Patients with mutations ⩾6 showed higher rate of achieving major molecular response than those<6 (P=0.0381). Mutations in epigenetic regulator, ASXL1, TET2, TET3, KDM1A and MSH6 were found in 25% of patients. TET2 or TET3, AKT1 and RUNX1 were mutated in one patient each. ASXL1 was mutated within exon 12 in three cases. Mutated genes were significantly enriched with cell signaling and cell division pathways. Furthermore, DNA copy number analysis showed that 2 of 24 patients had uniparental disomy of chromosome 1p or 3q, which disappeared major molecular response was achieved. These mutations may play significant roles in CML pathogenesis in addition to the strong driver mutation BCR-ABL1.


Assuntos
Proteínas de Ligação a DNA/genética , Dioxigenases/genética , Histona Desmetilases/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Fatores Etários , Variações do Número de Cópias de DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Epigênese Genética/genética , Feminino , Proteínas de Fusão bcr-abl/genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Contagem de Leucócitos , Masculino , Mutação , Inibidores de Proteínas Quinases/administração & dosagem , Transdução de Sinais , Sequenciamento do Exoma
3.
Leukemia ; 31(4): 861-871, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27694924

RESUMO

Somatic inactivating mutations in epigenetic regulators are frequently found in combination in myelodysplastic syndrome (MDS). However, the mechanisms by which combinatory mutations in epigenetic regulators promote the development of MDS remain unknown. Here we performed epigenomic profiling of hematopoietic progenitors in MDS mice hypomorphic for Tet2 following the loss of the polycomb-group gene Ezh2 (Tet2KD/KDEzh2Δ/Δ). Aberrant DNA methylation propagated in a sequential manner from a Tet2-insufficient state to advanced MDS with deletion of Ezh2. Hyper-differentially methylated regions (hyper-DMRs) in Tet2KD/KDEzh2Δ/Δ MDS hematopoietic stem/progenitor cells were largely distinct from those in each single mutant and correlated with transcriptional repression. Although Tet2 hypomorph was responsible for enhancer hypermethylation, the loss of Ezh2 induced hyper-DMRs that were enriched for CpG islands of polycomb targets. Notably, Ezh2 targets largely lost the H3K27me3 mark while acquiring a significantly higher level of DNA methylation than Ezh1 targets that retained the mark. These findings indicate that Ezh2 targets are the major targets of the epigenetic switch in MDS with Ezh2 insufficiency. Our results provide a detailed trail for the epigenetic drift in a well-defined MDS model and demonstrate that the combined dysfunction of epigenetic regulators cooperatively remodels the epigenome in the pathogenesis of MDS.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Epigênese Genética , Regulação da Expressão Gênica , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Ilhas de CpG , Metilação de DNA , Proteínas de Ligação a DNA/genética , Dioxigenases , Modelos Animais de Doenças , Elementos Facilitadores Genéticos , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Hematopoese/genética , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Motivos de Nucleotídeos , Ligação Proteica , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo
4.
Biomarkers ; 21(2): 164-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26635084

RESUMO

Diabetic nephropathy has dramatically increased worldwide. In this study, we measured urinary podocalyxin in 240 patients with diabetes. The relationship between urinary podocalyxin and clinical parameters and the effects of dipeptidyl peptidase-4 inhibitors (DPP4i) and alpha-glucosidase inhibitor (a-GI) on urinary podocalyxin levels were examined. Urinary podocalyxin levels were significantly higher in patients with microalbuminuria than in those with normoalbuminuria. Urinary podocalyxin levels were also significantly related to albumin-to-creatinine ratio. Neither DPP4i nor α-GI ameliorated the increase in urinary podocalyxin levels. Our results indicated that urinary podocalyxin will be not only an early marker but also a treatment target for DN.


Assuntos
Albuminúria/urina , Biomarcadores/urina , Diabetes Mellitus Tipo 2/urina , Sialoglicoproteínas/urina , Idoso , Creatinina/urina , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/urina , Progressão da Doença , Diagnóstico Precoce , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada
5.
Horm Metab Res ; 47(3): 176-83, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25295420

RESUMO

Type 2 diabetes results from the failure of beta-cells to adequately compensate for insulin resistance. Although the reduction of beta-cell mass is because of increased cell death and/or inadequate replication or neogenesis, the mechanism underlying beta-cell mass reduction is not fully understood. Here, we clarify the role of insulin signaling pathway in the beta-cell apoptosis using insulin resistant model mice. Wild-type mice and those carrying a mutation in the insulin receptor (mIR) were fed either regular chow or a high-fat diet for 6 weeks and subsequently investigated for beta-cell apoptosis, endoplasmic reticulum stress, and oxidative stress. Insulin tolerance tests revealed that mIR mice fed a high-fat diet (mIRHF) had higher insulin resistance. Beta-cell apoptosis was increased 2-fold in the wild-type mice fed a high-fat diet (wHF) compared with control mice, whereas beta-cell apoptosis in mIRHF mice did not increase compared with that in mIR mice. The expression of endoplasmic reticulum stress markers in isolated islets did not differ between the groups. Staining of 8-hydroxy-2'-deoxyguanosine and 4-hydroxy-2-nonenal in islets of wHF mice significantly increased, but the staining in mIRHF mice was not different from that in control group. Gene expression of the antioxidant enzyme MnSOD was significantly higher in mIRHF mice than those in the other 3 groups. A mutation in the insulin receptor attenuated the oxidative stress and apoptosis in beta-cells even though high caloric nutrient was loaded. Our results suggest that reduced insulin signaling protects beta-cells thorough decline of oxidative stress.


Assuntos
Apoptose , Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Insulina/metabolismo , Mutação , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Receptor de Insulina/genética , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/citologia , Masculino , Camundongos , Receptor de Insulina/metabolismo , Transdução de Sinais
6.
Diabetes Obes Metab ; 16(8): 761-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24447683

RESUMO

We assessed the efficacy and safety of sitagliptin compared with α-glucosidase inhibitor (αGI) in 120 of Japanese patients with type 2 diabetes mellitus (T2DM) inadequately controlled on stable ≤2 mg/day glimepiride alone [mean hemoglobin A1c (HbA1c) 7.7%] by the randomized, active-controlled, non-inferiority trial. Patients were randomly assigned to receive additional sitagliptin or αGI for 24 weeks. The primary endpoint was change in HbA1c from baseline to week 12. After 12 weeks, sitagliptin reduced HbA1c by -0.44% (p < 0.001) relative to αGI. At 24 weeks, the reduction was almost identical between the groups (-0.091%, p = 0.47). Gastrointestinal disorders were more common with αGI than with sitagliptin, but only minor hypoglycaemia occurred in both groups at similar frequency. These data suggested that sitagliptin was not inferior to αGI for reduction of HbA1c in Japanese T2DM patients receiving glimepiride alone, and well tolerated with minimum risk of gastrointestinal symptoms and hypoglycaemia.


Assuntos
1-Desoxinojirimicina/análogos & derivados , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Inibidores de Glicosídeo Hidrolases/uso terapêutico , Hiperglicemia/prevenção & controle , Inositol/análogos & derivados , Pirazinas/uso terapêutico , Triazóis/uso terapêutico , 1-Desoxinojirimicina/efeitos adversos , 1-Desoxinojirimicina/uso terapêutico , Idoso , Diabetes Mellitus Tipo 2/sangue , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Quimioterapia Combinada/efeitos adversos , Feminino , Fármacos Gastrointestinais/efeitos adversos , Fármacos Gastrointestinais/uso terapêutico , Hemoglobinas Glicadas/análise , Inibidores de Glicosídeo Hidrolases/efeitos adversos , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemia/prevenção & controle , Hipoglicemiantes/uso terapêutico , Inositol/efeitos adversos , Inositol/uso terapêutico , Japão , Masculino , Pessoa de Meia-Idade , Pirazinas/efeitos adversos , Fosfato de Sitagliptina , Compostos de Sulfonilureia/uso terapêutico , Triazóis/efeitos adversos , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
7.
Transpl Infect Dis ; 15(2): E54-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23173742

RESUMO

Severe hyponatremia is a critical electrolyte abnormality in allogeneic stem cell transplantation (allo-SCT) recipients and >50% of cases of severe hyponatremia are caused by the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Here, we present a patient with rapidly progressive severe hyponatremia as an initial sign and symptom of human herpesvirus-6-associated post-transplantation acute limbic encephalitis (HHV-6 PALE) after allo-SCT. A 45-year-old woman with acute lymphoblastic leukemia received unrelated bone marrow transplantation from a one locus-mismatched donor at the DR locus. On day 21, she developed a generalized seizure and loss of consciousness with severe hyponatremia, elevated serum antidiuretic hormone (ADH), and decreased serum osmolality. A high titer of HHV-6 DNA was detected in cerebrospinal fluid. Treatment with foscarnet sodium and hypertonic saline was started with improvement of neurological condition within several days. Although an elevated serum ADH, low serum osmolality, and high urinary osmolality persisted for 2 months, she had no other recurrent symptoms of encephalitis. Our experience suggests that hyponatremia accompanied by SIADH should be recognized as a prodromal or concomitant manifestation of HHV-6 PALE, and close monitoring of serum sodium levels in high-risk patients for HHV-6 PALE is necessary for immediate diagnosis and treatment initiation.


Assuntos
Antivirais/uso terapêutico , Transplante de Medula Óssea , Herpesvirus Humano 6/isolamento & purificação , Hiponatremia/diagnóstico , Síndrome de Secreção Inadequada de HAD/diagnóstico , Encefalite Límbica/diagnóstico , Infecções por Roseolovirus/diagnóstico , DNA Viral/líquido cefalorraquidiano , Diagnóstico Diferencial , Feminino , Foscarnet/uso terapêutico , Herpesvirus Humano 6/genética , Humanos , Hiponatremia/etiologia , Hiponatremia/terapia , Síndrome de Secreção Inadequada de HAD/complicações , Síndrome de Secreção Inadequada de HAD/terapia , Encefalite Límbica/tratamento farmacológico , Encefalite Límbica/virologia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Infecções por Roseolovirus/tratamento farmacológico , Infecções por Roseolovirus/virologia , Solução Salina Hipertônica/uso terapêutico , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X
12.
Int J Obes Relat Metab Disord ; 25(2): 292-5, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11410834

RESUMO

OBJECTIVE: Studies were made on the abnormality of glucose and lipid metabolism and its cause in four patients with Werner's syndrome to infer the reason for accelerated atherogenesis in this syndrome. RESULTS: Of these four patients, hypercholesterolemia was found in three, hypertriglyceridemia in four, hypoalphalipoproteinemia in two and hypertension in two. All the patients had insulin-resistant diabetes mellitus and three of them had apparent hyperinsulinemia. Abdominal computed tomography revealed that all of them had visceral fat obesity, namely augumented intra-abdominal adipose tissue. CONCLUSION: The clinical features of these patients resemble those recently designated as insulin resistant syndrome (syndrome X) or visceral fat syndrome. The metabolic abnormality may be one of important factors in the accelerated atherogenesis in this syndrome.


Assuntos
Abdome , Tecido Adiposo/anatomia & histologia , Arteriosclerose/etiologia , Glucose/metabolismo , Metabolismo dos Lipídeos , Síndrome de Werner/metabolismo , Adulto , Feminino , Humanos , Hiperinsulinismo/metabolismo , Hiperlipidemias/metabolismo , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Síndrome de Werner/fisiopatologia
13.
Br J Pharmacol ; 133(1): 83-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11325797

RESUMO

1. It has been suggested that osteopontin promotes the development of atherosclerosis, especially under diabetic conditions. 2. In the present study, we found that NK-104, a new potent synthetic inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, reduced osteopontin expression both at protein and mRNA levels in cultured rat aortic smooth muscle cells. 3. The inhibitory effect of NK-104 was almost completely reversed by mevalonate, suggesting that mevalonate or its metabolites play important roles in the regulation of osteopontin expression. 4. Furthermore, oral administration of NK-104 (3 mg kg(-1) day(-1) for 7 days) effectively suppressed abnormally upregulated expression of osteopontin mRNA in the aorta and kidney of streptozotocin-induced diabetic rats. 5. These data support a notion that NK-104 is a suitable drug for the treatment of diabetic patients with hypercholesterolaemia.


Assuntos
Aorta/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Quinolinas/farmacologia , Sialoglicoproteínas/genética , Administração Oral , Animais , Aorta/citologia , Aorta/metabolismo , Western Blotting , Células Cultivadas , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Ácido Mevalônico/farmacologia , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Osteopontina , Quinolinas/administração & dosagem , Quinolinas/antagonistas & inibidores , Quinolinas/uso terapêutico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Sialoglicoproteínas/biossíntese
14.
Ann N Y Acad Sci ; 902: 357-63, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10865863

RESUMO

Atherosclerotic vascular disease is a major complication of diabetic patients. Osteopontin has recently been implicated in the development of atherosclerosis. In the present study, we have investigated the effects of high glucose on expression of osteopontin in cultured rat aortic smooth muscle cells. High concentrations of glucose increased osteopontin secretion from the cells, and the increased secretion was completely inhibited by an inhibitor of protein kinase C, GF109203X. Northern blot analysis confirmed the enhanced effect of glucose on expression of osteopontin mRNA. Promoter activity of osteopontin, measured using the osteopontin promoter/luciferase expression vector system, was increased by high glucose, and the enhanced effect was completely inhibited by GF109203X. Glucosamine also increased the promoter activity of osteopontin. Azaserine, an inhibitor of glutamine:fructose-6-phosphate amidotransferase, the key enzyme of the hexosamine pathway, profoundly inhibited high glucose-mediated increase in the promoter activity. Taken together, these data indicate that high glucose enhances the expression of osteopontin at the transcriptional level possibly through the activation of protein kinase C as well as the hexosamine pathway. Our results suggest that osteopontin could play a role in the development of diabetic vascular complications.


Assuntos
Angiopatias Diabéticas/fisiopatologia , Regulação da Expressão Gênica , Glucose/farmacologia , Músculo Liso Vascular/fisiologia , Sialoglicoproteínas/genética , Animais , Aorta , Arteriosclerose/fisiopatologia , Adesão Celular , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Indóis/farmacologia , Maleimidas/farmacologia , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Osteopontina , Regiões Promotoras Genéticas , Proteína Quinase C/metabolismo , RNA Mensageiro/genética , Ratos , Transcrição Gênica
15.
Kyobu Geka ; 53(6): 511-3, 2000 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-10846369

RESUMO

A 59-year-old male clerk consulted in general practitioner due to cough and hemoptysis. A mass shadow was pointed out in the left upper lung field on a chest radiograph. Patient was referred to our hospital for further treatment. Any definitive daiagnosis could not be made after examinations including sputum culture, cytology and TBLB. Because a lung cancer was strongly suspected, an exploratory thoracotomy was performed. Actinomyces was detected by pathological study of excised specimen, with no evidence of cancer. ABPC was administered for two months postoperatively. The patient is doing well without recurrence of actinomycosis 2.5 years after the surgery. Pulmonary actinomycosis presenting a mass shadow on a radiograph may mimick a pulmonary tumor, especially a lung cancer. Pulmonary actinomycosis should be considered in a differential diagnosis of pulmonary lesion thought to be malignant.


Assuntos
Actinomicose/diagnóstico por imagem , Pneumopatias Fúngicas/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
16.
Atherosclerosis ; 149(2): 351-8, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10729385

RESUMO

The mechanism of diabetic macroangiopathy was studied from the view point of phenotypic change of arterial smooth muscle cells (SMC). Otsuka Long-Evans Tokushima fatty (OLETF) rat, an animal model of non-insulin dependent diabetes mellitus (NIDDM), develops spontaneous persistent hyperglycemia after the age of 18 weeks. Medial SMC in OLETF rats expressed more platelet-derived growth factor (PDGF) beta-receptor and fibronectin at the protein level than those from control, Long-Evans Tokushima Otsuka (LETO) rats, not only after but also before the onset of diabetes mellitus. Cultured SMC from OLETF rats more strongly responded specifically to the mitogenic stimuli of PDGF-AB and PDGF-BB and also expressed PDGF beta-receptor more intensely compared with those from LETO rats. PDGF is known to be the main contributor to the intimal thickening induced by balloon catheter injury, which is one of several forms of arterial injuries. Intimal thickening of carotid arteries in OLETF rats after balloon catheter injury increased compared with that in LETO rats before the onset of diabetes mellitus. In in vitro culture system, fibronectin synthesis was stimulated by transforming growth factor-beta1(TGF-beta1) in SMC from OLETF rats, but not in those from LETO rats, suggesting that SMC from OLETF rats respond to TGF-beta1. These results indicate that overexpression of PDGF beta-receptor and fibronectin in medial SMC plays an important role in the accelerated intimal thickening before the onset of diabetes mellitus in OLETF rats.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Fibronectinas/metabolismo , Músculo Liso Vascular/metabolismo , Fator de Crescimento Derivado de Plaquetas/análise , Receptor beta de Fator de Crescimento Derivado de Plaquetas/análise , Animais , Aorta Torácica/citologia , Aorta Torácica/patologia , Becaplermina , Divisão Celular , Células Cultivadas , DNA/análise , DNA/biossíntese , Modelos Animais de Doenças , Fibronectinas/análise , Masculino , Músculo Liso Vascular/citologia , Músculo Liso Vascular/patologia , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteínas Proto-Oncogênicas c-sis , Ratos , Ratos Endogâmicos OLETF , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Valores de Referência , Sensibilidade e Especificidade , Túnica Íntima/lesões , Túnica Íntima/patologia
17.
Biochem Biophys Res Commun ; 270(1): 28-33, 2000 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-10733900

RESUMO

CrkII is an intracellular adaptor protein involved in signal transduction by various growth factors. Activation of PDGF alpha-receptor resulted in its association with CrkII in vivo. In contrast, binding of CrkII to the PDGF beta-receptor was negligible, despite its becoming prominently phosphorylated. Bacterially expressed GST-CrkII SH2 domain specifically bound to Tyr-762 and Tyr-771 in the activated PDGF alpha- and beta- receptors, respectively. GST fusion protein of full-length CrkII also bound to the activated PDGF beta-receptor. However, tyrosine phosphorylation of GST-CrkII diminished its binding to the beta-receptor. CrkI, a truncated version of CrkII lacking the phosphorylatable tyrosine residue, could bind to both PDGF alpha- and beta-receptors in vivo. In conclusion, tyrosine phosphorylation of CrkII negatively affects its binding to the PDGF receptors. The differential binding of CrkII to the PDGF alpha- and beta- receptors may be a rationale for functional diversity between the two receptors.


Assuntos
Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Animais , Modelos Biológicos , Fosforilação , Ligação Proteica , Proteínas Quinases/genética , Proteínas Proto-Oncogênicas c-crk , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Suínos , Tirosina/metabolismo , Domínios de Homologia de src
18.
Clin Chim Acta ; 293(1-2): 63-73, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10699423

RESUMO

The patient was a 39-year-old Japanese male with a body height of 160 cm and weight of 48 kg who was diagnosed as Werner syndrome of homozygote for mutation 4. His plasma total cholesterol (TC), triglycerides (TGs), high density lipoprotein-cholesterol (HDL-C) and apolipoprotein A-I (apo A-I) levels were 7.2, 2.1, 1 mmol/l and 128 mg/dl, respectively. During the clinical course of treatment of this patient, his plasma levels of HDL-C and apo A-I declined drastically to levels of as low as 0.2 mmol/l and 10 mg/dl, respectively, with concurrent reciprocal increase in plasma TG levels. Plasma HDL-C, apo A-I and TG levels gradually returned to original values. Lipoprotein lipase activity and mass in post-heparin plasma were markedly low when the apo A-I and HDL-C levels decreased to 10 mg/dl and 0.21 mmol/l, respectively, and these values improved when the apo A-I and HDL-C levels returned to more normal values of 106 mg/dl and 0.94 mmol/l, respectively. The result of direct sequence of the exon 3 and 4, and the promoter region of the apo A-I gene of the patient revealed no single nucleotide changes. These results suggest that in the present patient, impaired hydrolysis of TGs in TG-rich lipoproteins, is due at least in part to a decreased LPL enzyme level, reduced the formation of nascent HDL, resulting in unusually low plasma levels of HDL-C and apo A-I.


Assuntos
Apolipoproteína A-I/sangue , HDL-Colesterol/sangue , Lipoproteínas HDL/sangue , Síndrome de Werner/sangue , Adulto , Anticolesterolemiantes/uso terapêutico , Apolipoproteína A-I/genética , Bezafibrato/uso terapêutico , Humanos , Hipolipemiantes/uso terapêutico , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Pravastatina/uso terapêutico , Probucol/uso terapêutico , Fatores de Tempo , Triglicerídeos/sangue , Síndrome de Werner/tratamento farmacológico , Síndrome de Werner/genética
19.
Arterioscler Thromb Vasc Biol ; 20(3): 624-8, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10712383

RESUMO

We have previously reported that high glucose stimulates osteopontin (OPN) expression through protein kinase C-dependent pathways as well as hexosamine pathways in cultured rat aortic smooth muscle cells. The finding prompted us to study in vivo expression of OPN in diabetes mellitus. In the present study, we found by immunohistochemistry that medial layers of the carotid arteries of streptozotocin-induced diabetic rats and the forearm arteries of diabetic patients stained positively for OPN antibodies, whereas the staining from arteries of control rats and nondiabetic patients was negative. We also found that OPN stimulated the migration and enhanced platelet-derived growth factor (PDGF)-mediated DNA synthesis of cultured rat aortic smooth muscle cells. OPN and PDGF synergistically activated focal adhesion kinase as well as extracellular signal-regulated kinase; this finding seems to explain the OPN-induced enhancement of PDGF-mediated DNA synthesis. Taken together, our present results raise a possibility that OPN plays a role in the development of diabetic vascular complications.


Assuntos
Arteriosclerose/etiologia , Arteriosclerose/metabolismo , Proteínas de Ligação a DNA , Angiopatias Diabéticas/metabolismo , Músculo Liso Vascular/enzimologia , Sialoglicoproteínas/biossíntese , Fatores de Transcrição , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Aorta/citologia , Aorta/enzimologia , Becaplermina , Artérias Carótidas/metabolismo , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Células Cultivadas , DNA/biossíntese , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ativação Enzimática/efeitos dos fármacos , Feminino , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Antebraço/irrigação sanguínea , Humanos , Masculino , Microcirculação/fisiologia , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/citologia , Osteopontina , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-sis , Ratos , Ratos Wistar , Sialoglicoproteínas/farmacologia , Proteínas Elk-1 do Domínio ets
20.
Nihon Ronen Igakkai Zasshi ; 36(9): 648-51, 1999 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-10572450

RESUMO

A 56-year-old woman with Werner's syndrome was admitted to our hospital because of intractable foot ulcer and malnutrition. She presented dementia consisting of childish behaviour, loss of intelligence, and severe amnesia. Brain CT revealed diffuse periventricular low density areas, and brain MRI also disclosed periventricular high intensity areas under T2-intensified conditions. These findings gave a diagnosis of progressive subcortical vascular encephalopathy of the Binswanger type, which seemed to be the cause of her dementia. She finally died of heart failure due to acute myocardial infarction. Mild to moderate demyelinization was found in the subcortical area of the autopsied cerebrum, confirming the clinical diagnosis. Generalized atherosclerosis characteristic of Werner's syndrome may have predisposed this patient to Binswanger's encephalopathy.


Assuntos
Encéfalo/patologia , Demência Vascular/complicações , Síndrome de Werner/complicações , Demência Vascular/diagnóstico , Feminino , Humanos , Arteriosclerose Intracraniana/complicações , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade
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