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1.
Osteoporos Int ; 29(5): 1203-1209, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29492624

RESUMO

Evaluation of bone is of great importance in chronic kidney disease patients, as these patients are at an increased risk for fractures. We treated a hemodialysis patient suffering from hyperparathyroid bone disease with cinacalcet hydrochloride and concurrent administration of maxacalcitol and alfacalcidol for a year. Hyperparathyroid bone disease is characterized by cortical thinning, increased cortical porosity, reduced trabecular bone volume, and increased hypomineralized matrix volume, and there is little information to date about the effects of treatment with cinacalcet hydrochloride on the bone fragility in patients with hyperparathyroid bone disease. In the present study, histological and backscattered electron microscopic evaluation of this combination treatment revealed an excellent improvement of both bone volume and bone morphology. This treatment improved cortical thinning, cortical porosity, and trabecular thinning. Furthermore, the treatment also reduced hypomineralized matrix volume, indicative of improved mineralization by osteocytes. We speculate that the intermittent maxacalcitol administration may have effectively stimulated the vitamin D receptors expressed on osteocytes and osteoblasts, resulting in increased mineralization. Our approach for evaluating the bone in patients with chronic kidney disease by backscattered electron microscopy is novel.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Distúrbio Mineral e Ósseo na Doença Renal Crônica/tratamento farmacológico , Hiperparatireoidismo Secundário/complicações , Ílio/ultraestrutura , Biópsia , Calcitriol/análogos & derivados , Calcitriol/uso terapêutico , Distúrbio Mineral e Ósseo na Doença Renal Crônica/patologia , Cinacalcete/uso terapêutico , Humanos , Hidroxicolecalciferóis/uso terapêutico , Hiperparatireoidismo Secundário/patologia , Ílio/patologia , Microscopia Eletrônica , Pessoa de Meia-Idade
2.
Nat Commun ; 8(1): 1001, 2017 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-29042554

RESUMO

Recently, nanocarriers that transport bioactive substances to a target site in the body have attracted considerable attention and undergone rapid progression in terms of the state of the art. However, few nanocarriers can enter the brain via a systemic route through the blood-brain barrier (BBB) to efficiently reach neurons. Here we prepare a self-assembled supramolecular nanocarrier with a surface featuring properly configured glucose. The BBB crossing and brain accumulation of this nanocarrier are boosted by the rapid glycaemic increase after fasting and by the putative phenomenon of the highly expressed glucose transporter-1 (GLUT1) in brain capillary endothelial cells migrating from the luminal to the abluminal plasma membrane. The precisely controlled glucose density on the surface of the nanocarrier enables the regulation of its distribution within the brain, and thus is successfully optimized to increase the number of nanocarriers accumulating in neurons.There are only a few examples of nanocarriers that can transport bioactive substances across the blood-brain barrier. Here the authors show that by rapid glycaemic increase the accumulation of a glucosylated nanocarrier in the brain can be controlled.


Assuntos
Glicemia/metabolismo , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Portadores de Fármacos/farmacocinética , Animais , Encéfalo/irrigação sanguínea , Portadores de Fármacos/metabolismo , Feminino , Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Glicosilação , Humanos , Camundongos Endogâmicos BALB C , Micelas , Microscopia Confocal , Nanopartículas/metabolismo , Neurônios/metabolismo , Polímeros/química , Polímeros/metabolismo
3.
Osteoporos Int ; 26(3): 1017-28, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25366373

RESUMO

UNLABELLED: Serum sclerostin levels could be closely associated with serum phosphate and fibroblast growth factor-23 levels in hemodialysis patients with low intact parathyroid hormone (PTH) levels. Further study is required to indicate whether these close associations are present in patients with spontaneously low PTH levels without any vitamin D treatment. INTRODUCTION: Intact parathyroid hormone (iPTH) is involved in the interaction between sclerostin and phosphate/fibroblast growth factor-23 (FGF23) in animal models. However, their relationship in patients on hemodialysis (HD) is unclear. METHODS: Data of 102 HD patients were collected regarding clinical and laboratory parameters and mineral bone disorder medications. The patients were divided into subgroups according to the iPTH level (A, <70 pg/mL; B, 70-150 pg/mL; C, 150-300 pg/mL; and D, ≥ 300 pg/mL). RESULTS: The sclerostin level was significantly and positively correlated with phosphate and log of FGF23 levels in subgroups A, B, and combined A and B. Multiple linear regression analysis in the combined A and B subgroup revealed that male sex (t = 3.24, P = 0.01; 95% confidence interval [CI] 11.78 to 50.43) and phosphate level (t = 2.13, P = 0.04; 95% CI, 1.08 to 36.91) were independent factors for serum sclerostin level. The log of serum FGF23 level (t = 1.90, P = 0.06, 95% CI -1.85 to 63.50) appeared to be an important factor for serum sclerostin level. The frequency of patients using vitamin D treatment was not significantly different among subgroups A (93.1%), B (88.0%), C (85.2%), and D (90.5%). CONCLUSION: Serum sclerostin levels were associated with serum phosphate and FGF23 levels in patients with low iPTH levels. Further study is required to indicate whether these close associations are present in patients with spontaneously low iPTH levels without vitamin D treatment.


Assuntos
Proteínas Morfogenéticas Ósseas/sangue , Hormônio Paratireóideo/deficiência , Diálise Renal , Vitamina D/uso terapêutico , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Suplementos Nutricionais , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/sangue , Marcadores Genéticos , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Fosfatos/sangue , Adulto Jovem
4.
Plant Biol (Stuttg) ; 16(1): 258-63, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23574545

RESUMO

Although most cyanobacterial cells contain prominent polyphosphate bodies in the central cytoplasmic area enclosed by the peripheral thylakoid membranes, their roles are not fully understood. Storing phosphate for nucleotide production might be one of their important roles in survival of the cells. As a step towards identifying a possible contribution of the polyphosphate bodies to DNA synthesis, the relationship between polyphosphate bodies and DNA throughout cell division cycle of Synechococcus elongatus PCC 7942 cells cultured under light/dark cycles was investigated with light and electron microscopy. During the dark period, the average size of polyphosphate bodies increased gradually without significant change in their number and distribution. However, during the light period, the number of polyphosphate bodies increased, while the size of each polyphosphate body decreased and cells elongated until the end of the light period, when most cells divided. The ratio of the content of polyphosphate bodies to cell length increased gradually during the dark period and decreased during the light period. Hoechst 33342-stained DNA appeared diffuse during the dark period, but in the light period it became condensed and eventually formed a wavy, rope-like structure prior to cell division. Close association between fibres containing DNA and polyphosphate bodies was demonstrated by TEM using DNA-specific staining and BrdU labelling. These regular coordinated changes of polyphosphate bodies and DNA shape during the cell division cycle, together with their intimate interaction, imply a role of polyphosphate bodies in supplying material for DNA.


Assuntos
Divisão Celular , DNA Bacteriano/metabolismo , Polifosfatos/metabolismo , Synechococcus/citologia , Synechococcus/genética , Synechococcus/metabolismo
5.
Glycoconj J ; 31(2): 171-84, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24271942

RESUMO

SBL/RC-RNase was originally isolated from frog (Rana catesbeiana) oocytes and purified as a novel sialic acid-binding lectin (SBL) that displayed strong anti-cancer activity. SBL was later shown to be identical to a ribonuclease (RC-RNase) from oocytes of the same species. The administration of SBL/RC-RNase induced apoptosis (with nuclear condensation and DNA fragmentation) in mouse leukemia P388 cells but did not kill umbilical vein endothelial or fibroblast cells derived from normal tissues. The cytotoxic activity of SBL/RC-RNase was inhibited by desialylation of P388 cells and/or the co-presence of free bovine submaxillary mucin. FACS analysis showed that SBL/RC-RNase was incorporated into cells after attachment to cholesterol-rich microdomains. Addition of the cholesterol remover methyl-ß-cyclodextrin reduced SBL/RC-RNase-induced apoptosis. Apoptosis occurred through the caspase-3 pathway following activation of caspase-8 by SBL/RC-RNase. A heat shock cognate protein (Hsc70) and a heat shock protein (Hsp70) (each 70 kDa) on the cell membrane were shown to bind to SBL/RC-RNase by mass spectrometric and flow cytometric analyses. Quercetin, an inhibitor of Hsc70 and Hsp70, significantly reduced SBL/RC-RNase-induced apoptosis. Taken together, our findings suggest that sialyl-glycoconjugates present in cholesterol-rich microdomains form complexes with Hsc70 or Hsp70 that act as triggers for SBL/RC-RNase to induce apoptosis through a pathway involving the activation of caspase-3 and caspase-8.


Assuntos
Apoptose/fisiologia , Colesterol/química , Glicoconjugados/metabolismo , Microdomínios da Membrana/química , Oócitos/enzimologia , Ribonucleases/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular , Proteínas de Choque Térmico HSC70/metabolismo , Proteínas de Choque Térmico HSP72/metabolismo , Leucemia P388 , Microdomínios da Membrana/metabolismo , Camundongos , Ácido N-Acetilneuramínico/química , Rana catesbeiana
6.
Bone Marrow Transplant ; 48(7): 972-6, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23318535

RESUMO

The emergence of microalbuminuria following conditioning chemotherapy may predict the development of renal dysfunction. To confirm this, a 1-year retrospective cohort study was conducted in 31 myeloablative allogeneic SCT patients who received five consecutive measurements of albuminuria before conditioning therapy and on days 0, 7, 14 and 28 following SCT. The cohort had neither microalbuminuria nor renal dysfunction at baseline. Microalbuminuria was defined as an albumin-creatinine (Cr) ratio over 30 mg/g, and renal dysfunction was as an estimated glomerular filtration rate <60 mL/min per 1.73 m(2). Cumulative incidence of renal dysfunction over time was analyzed by the Kaplan-Meier method. Multivariate Cox proportional hazards analysis was used to examine an association of de novo microalbuminuria with the incidence of renal dysfunction. In all, 16 patients (52%) developed microalbuminuria that was positive at least two times among the four measurements after SCT. The actuarial occurrence of chronic kidney disease was significantly higher in patients who developed microalbuminuria than in those who did not. Incidence of microalbuminuria had a significant risk of subsequent renal dysfunction (hazard ratio (95% confidence interval), 7.3 (1.2-140)). In conclusion, de novo microalbuminuria following conditioning therapy is a warning of near-term loss of renal function.


Assuntos
Albuminúria , Taxa de Filtração Glomerular , Transplante de Células-Tronco , Condicionamento Pré-Transplante , Adulto , Albuminúria/epidemiologia , Albuminúria/etiologia , Albuminúria/fisiopatologia , Albuminúria/urina , Aloenxertos , Doença Crônica , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
7.
Nutr Metab Cardiovasc Dis ; 23(7): 619-27, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22608251

RESUMO

BACKGROUND AND AIMS: Serum malondialdehyde-modified low-density lipoprotein (MDA-LDL) and MDA-LDL/LDL-cholesterol (LDL-c) ratio are risk factors for arteriosclerosis and cardiovascular disease (CVD). However, no information is available on these parameters or their associations with coronary artery calcification (CAC) in haemodialysis (HD) patients. METHODS AND RESULTS: Fifty-seven HD patients and 26 control subjects were included in this cross-sectional study. Serum MDA-LDL concentrations and MDA-LDL/LDL-c ratios were examined. HD patients had significantly higher MDA-LDL/LDL-c ratios than the controls (105.1 ± 27.5 vs. 81.4 ± 18.9 mU/mg, P < 0.001); however, there was no significant difference in serum MDA-LDL levels between the 2 groups. CAC scores were examined only in HD patients and their possible associations with the clinical/laboratory data were analysed. Analysis of HD patients showed that MDA-LDL/LDL-c ratio has an association with presence of CVD, CAC score, HD duration, MDA-LDL, or haemoglobin A1C. In addition, the CAC score was positively correlated with serum MDA-LDL level (P = 0.048) and MDA-LDL/LDL-c ratio (P = 0.006). Furthermore, multivariate logistic regression analysis showed that MDA-LDL/LDL-c ratio (ß = 0.04, P = 0.003) and HD duration (ß = 0.16, P = 0.007) were independently associated with CAC score. CONCLUSION: The MDA-LDL/LDL-c ratio of HD patients was significantly higher than that of non-HD subjects and was independently associated with the CAC score. Therefore, this ratio could be an important risk factor for CAC in HD patients.


Assuntos
LDL-Colesterol/sangue , Doença da Artéria Coronariana/sangue , Lipoproteínas LDL/sangue , Diálise Renal/efeitos adversos , Calcificação Vascular/sangue , Idoso , Algoritmos , LDL-Colesterol/química , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/fisiopatologia , Estudos Transversais , Feminino , Humanos , Japão/epidemiologia , Lipoproteínas LDL/química , Modelos Logísticos , Masculino , Malondialdeído/sangue , Malondialdeído/química , Pessoa de Meia-Idade , Insuficiência Renal/terapia , Fatores de Risco , Índice de Gravidade de Doença , Calcificação Vascular/epidemiologia , Calcificação Vascular/etiologia , Calcificação Vascular/fisiopatologia
8.
J Virol ; 87(1): 124-36, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23055559

RESUMO

The structural and functional analysis of the protein AvtR encoded by Acidianus filamentous virus 6 (AFV6), which infects the archaeal genus Acidianus, revealed its unusual structure and involvement in transcriptional regulation of several viral genes. The crystal structure of AvtR (100 amino acids) at 2.6-Å resolution shows that it is constituted of a repeated ribbon-helix-helix (RHH) motif, which is found in a large family of bacterial transcriptional regulators. The known RHH proteins form dimers that interact with DNA using their ribbon to create a central ß-sheet. The repeated RHH motifs of AvtR superpose well on such dimers, but its central sheet contains an extra strand, suggesting either conformational changes or a different mode of DNA binding. Systematic evolution of ligands by exponential enrichment (SELEX) experiments combined with systematic mutational and computational analysis of the predicted site revealed 8 potential AvtR targets in the AFV6 genome. Two of these targets were studied in detail, and the complex role of AvtR in the transcriptional regulation of viral genes was established. Repressing transcription from its own gene, gp29, AvtR can also act as an activator of another gene, gp30. Its binding sites are distant from both genes' TATA boxes, and the mechanism of AvtR-dependent regulation appears to include protein oligomerization starting from the protein's initial binding sites. Many RHH transcriptional regulators of archaeal viruses could share this regulatory mechanism.


Assuntos
Acidianus/virologia , Proteínas de Ligação a DNA/química , Lipothrixviridae/química , Proteínas Virais/química , Acidianus/genética , Sequência de Aminoácidos , Cristalografia por Raios X , Análise Mutacional de DNA , DNA Viral/metabolismo , Proteínas de Ligação a DNA/genética , Ensaio de Desvio de Mobilidade Eletroforética , Lipothrixviridae/genética , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/genética , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Proteínas Virais/genética
9.
Transplant Proc ; 42(5): 1476-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20620457

RESUMO

INTRODUCTION: There are few recent studies investigating increased risks for adverse effects leading to chronic kidney disease (CKD) among kidney donors. The aim of this study was to identify factors that protect renal function among actual live kidney donors. MATERIALS AND METHODS: We enrolled 68 individuals who had undergone donor nephrectomy in this study. We assessed donor age, body mass index (BMI), casual blood pressure, preoperative and 3-month follow-up serum creatinines, serum total cholesterol, and several other clinical parameters. The severity of arteriosclerosis in the arteriolar and interlobular arteries of the donor kidney was semiquantitatively evaluated in 4 grades using back table biopsies. Impairment of renal function after surgery was expressed by differences in serum creatinine levels. RESULTS: The ratio of glomerular sclerosis, systolic blood pressure, and diastolic blood pressure positively correlated with donor age. Deterioration of renal function after donor nephrectomy negatively correlated with BMI and positively correlated with severity of arteriosclerosis in interlobular arteries. A multiple regression analysis model with respect to the severity of arteriosclerosis in interlobular arteries showed significant influence, of serum creatinine and systolic blood pressure. CONCLUSIONS: Preventing progression of arteriosclerosis and selecting the optimal BMI before donor nephrectomy will help to avoid impaired renal function among live kidney donors.


Assuntos
Doadores Vivos , Nefrectomia/efeitos adversos , Adulto , Idoso , Arteriosclerose/epidemiologia , Arteriosclerose/patologia , Arteriosclerose/fisiopatologia , Índice de Massa Corporal , Colesterol/sangue , Creatinina/sangue , Diástole/fisiologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Renal/patologia , Fatores de Risco , Ácido Úrico/sangue
10.
Bone Marrow Transplant ; 45(9): 1427-34, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20062103

RESUMO

An observational cohort study was conducted to compare the performance of the RIFLE (risk, injury, failure, loss and end-stage kidney disease), AKIN (acute kidney injury network) and conventional graded criteria to identify acute kidney injury (AKI) following SCT and to predict long-term mortality in 141 myeloablative allogeneic SCT (m-allo), 60 non-myeloablative allogeneic SCT (nm-allo) and 48 autologous SCT (auto) cases. The AKIN criteria had less ability to identify patients as having the lowest category, stage 1 (analogous to RIFLE risk): 33% (37%) in m-allo, 23% (32%) in nm-allo and 8.3% (16.7%) in auto. Cox regression showed that categories higher than the intermediate stage were independent predictors of mortality in all three definitions. The areas under receiver operating characteristic curves showed that both definition systems had similar and significant ability to predict mortality (0.643-0.649 in m-allo and 0.734-0.766 in nm-allo, respectively). These abilities of the conventional graded criteria were comparable with those of the RIFLE criteria. The RIFLE criteria have greater sensitivity than the AKIN criteria to identify patients with AKI and therefore are more favorable as a uniform definition system for post-SCT AKI. However, the RIFLE criteria do not improve on the clinical relevance of the conventional graded criteria.


Assuntos
Injúria Renal Aguda/mortalidade , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Leucemia Mieloide Aguda/mortalidade , Mieloma Múltiplo/mortalidade , Adulto , Estudos de Coortes , Comorbidade , Feminino , Doença Enxerto-Hospedeiro/mortalidade , Humanos , Incidência , Falência Renal Crônica/mortalidade , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/terapia , Valor Preditivo dos Testes , Curva ROC , Fatores de Risco , Transplante Autólogo
11.
Int J Lab Hematol ; 32(2): 248-55, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19624802

RESUMO

The evaluation of iron status in dialysis patients provides information essential to the planning of adequate recombinant human erythropoietin treatment. The cellular iron status of the patients can be determined from the recently available measurement of reticulocyte hemoglobin equivalent (RET-He). RET-He is measured on the basis of automated fluorescent flow cytometry which in the reticulocyte channel, using a polymethine dye, also measures the mean value of the forward light scatter intensity of mature red blood cells and reticulocytes. These values equate with reticulocyte hemoglobin content. In this study, to clarify the accuracy of RET-He in diagnosing iron deficiency in dialysis patients, we initially compared RET-He with such iron parameters as serum ferritin levels, transferrin saturation and content of reticulocyte hemoglobin (CHr) which has been established as indicators of functional iron deficiency. Secondly, we investigated the changes in RET-He during iron supplementation for iron-deficient patients to determine whether this marker is a prospective and reliable indicator of iron sufficiency. The participants in this study were 217 haemodialysis patients. Iron deficiency was defined as havsing a transferrin saturation (TSAT) < 20% or serum ferritin < 100 ng/ml. Conventional parameters of red blood cells and RET-He were measured by on a XE-2100 automated blood cell counter (Sysmex). CHr was measured on an ADVIA120 autoanalyser (Siemens). RET-He mean value was 32.4 pg and good correlation (r = 0.858) between RET-He and CHr is obtained in dialysis patients. Receiver operating characteristic curve analysis revealed, values of the area was 0.776 and at a cutoff value of 33.0 pg, a sensitivity of 74.3% and a specificity of 64.9%, were achieved. Iron supplements given to the patients with low TSAT or ferritin, RET-He responded within 2 weeks, and this seemed to be a potential advantage of using RET-He in the estimation of iron status. RET-He is a new parameter, equivalent value to CHr, and is easily measurable on the widely spread and popular blood cell counter and is a sensitive and specific marker of iron status in dialysis patients.


Assuntos
Anemia Ferropriva/diagnóstico , Hemoglobinas , Deficiências de Ferro , Ferro/sangue , Diálise Renal , Reticulócitos/química , Biomarcadores/química , Humanos , Curva ROC , Contagem de Reticulócitos
12.
Biochemistry (Mosc) ; 74(7): 709-16, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19747090

RESUMO

A lectin was purified from Japanese sea hare Aplysia kurodai by lactosyl-agarose affinity chromatography. The molecular mass of the lectin was determined to be 56 and 32 kDa by SDS-PAGE under non-reducing and reducing conditions, respectively. It was found to agglutinate trypsinized and glutaraldehyde-fixed rabbit and human erythrocytes in the absence of divalent cations. The lectin exhibited stable thermo-tolerance as it retained hemagglutinating activity for 1 h even at 80 degrees C and showed stability at pH 10. By contrast, it was very sensitive at pH less than 5 and in the presence of the sulfhydryl-group preserving reagent, beta-mercaptoethanol. The hemagglutinating activity by the lectin was specifically inhibited by D-galactose, galacturonic acid, methyl-alpha- and methyl-beta-D-galactopyranoside, lactose, melibiose, and asialofetuin. The association rate constant (k(ass)) and dissociation rate constant (k(diss)) were determined for the lectin to be 4.3 x 10(5) M(-1) x sec(-1) and 2.2 x 10(-3) sec(-1), respectively, using a surface plasmon resonance biosensor. The lectin moderately inhibited cell proliferation in the P388 cell line dose dependently. Interestingly, lectin-treated cells did not show a fragmented DNA ladder as is caused by apoptosis, suggesting that the cell proliferation inhibition was caused by another unknown mechanism.


Assuntos
Aplysia/química , Galectinas/química , Galectinas/isolamento & purificação , Óvulo/química , Animais , Aplysia/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Feminino , Galectinas/metabolismo , Galectinas/farmacologia , Hemaglutinação/efeitos dos fármacos , Humanos , Cinética , Peso Molecular , Óvulo/metabolismo , Coelhos
13.
Clin Nephrol ; 72(1): 69-72, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19640390

RESUMO

Minimal change nephrotic syndrome (MCNS) usually is considered to have a good renal prognosis, but the frequency of relapses is a therapeutic challenge to physicians. The treatment of patients with multiple relapses remains a matter of controversy, because few controlled studies are available. We report the case of a 25-year-old man who experienced relapses of MCNS. Single-dose rituximab therapy (total dose 500 mg) was given during the fourth relapse. Complete remission occurred 10 days later, when no CD19/20-positive B cells were detected in the blood. This the first report of efficacy of single-dose rituximab therapy to treat multi-relapsing MCNS in an adult patient.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Fatores Imunológicos/administração & dosagem , Nefrose Lipoide/tratamento farmacológico , Adulto , Anticorpos Monoclonais Murinos , Humanos , Masculino , Recidiva , Rituximab , Resultado do Tratamento
14.
J Microsc ; 234(2): 118-23, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19397740

RESUMO

We have attempted to observe the native shape of DNA in rapidly frozen whole cyanobacterial cells through 5-bromo-2-deoxyuridine (BrdU) incorporation and visualization with a Hilbert differential contrast transmission electron microscopy (HDC TEM). The incorporation of BrdU into the DNA of Synechococcus elongatus PCC 7942 was confirmed with fluorescently labelled anti-BrdU antibodies and through EDX analysis of ultra-thin sections. HDC TEM observed cells that had incorporated BrdU into their DNA exhibited electron dense areas at the location corresponding to fluorescently labelled BrdU. Since various strings and strands were observed in high contrast with the HDC TEM, we conclude that the method promises to allow us to identify and understand bulk structural changes of the in vivo DNA and the nucleoid through observation at high resolution.


Assuntos
Bromodesoxiuridina/química , DNA Bacteriano/química , Microscopia Eletrônica de Transmissão/métodos , Synechococcus/química , Bromodesoxiuridina/metabolismo , DNA Bacteriano/metabolismo , Imunofluorescência , Gelo , Microscopia de Fluorescência , Synechococcus/metabolismo , Synechococcus/ultraestrutura , Difração de Raios X
15.
Cell Mol Life Sci ; 65(20): 3304-11, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18791848

RESUMO

Transforming growth factor (TGF-beta1) promotes renal fibrogenesis through activation of Smads. Galectin-1 is reported to prevent experimental glomerulonephritis. Here we investigated the fact that transfected galectin-1 significantly suppressed the transcription of alpha2(I) collagen (COL1A2) in TGF-beta1- activated human renal epithelial cells. Conversely, galectin-1 silencing RNA reduced secretion of type I collagen by HKC cells. Galectin-1 significantly decreased activation of a TGF-beta1-responsive reporter construct and of a minimal reporter construct that contains four repeats of the Smad binding element (SBE). Galectin-1 had no effect on phosphorylation of Smad3 at the linker region and C-terminus, whereas it decreased affinity of Smad3 to the SBE. Additionally, the inhibitory effect of galectin-1 disappeared using a mutated reporter construct, 376 m-LUC, in which a potential Smad recognition site within the promoter is mutated. Taken together, the results suggest that galectin-1 decreases Smad3-complex from binding to the SBE, down-regulating transcription of COL1A2 in TGF-beta1-stimulated renal epithelial cells.


Assuntos
Colágeno Tipo I/antagonistas & inibidores , Células Epiteliais/metabolismo , Galectina 1/metabolismo , Rim/citologia , Proteína Smad3/metabolismo , Sítios de Ligação , Linhagem Celular , Colágeno Tipo I/genética , Células Epiteliais/efeitos dos fármacos , Genes Reporter , Humanos , Regiões Promotoras Genéticas , Ligação Proteica/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Fator de Crescimento Transformador beta1/farmacologia
16.
Kidney Int ; 73(8): 926-32, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18256598

RESUMO

Phosphorylation of tyrosine residue (Y1204) of rat nephrin by Fyn kinase allows Nck adaptor protein binding to nephrin motifs, which include the phosphorylated tyrosine. This phosphorylation-dependent switch induces actin polymerization in a cell culture system. Here, we generated an antibody recognizing phosphorylated nephrin at the Nck binding sites pY1204 and pY1228 to determine the phosphorylation status of nephrin using a rat model of puromycin aminonucleoside-induced nephrosis. Changes in globular actin (G-actin) and filamentous actin (F-actin) contents in isolated glomeruli were measured by western blot. Before experimental nephrosis, both Y1204 and Y1228 were phosphorylated, and most of the actin was filamentous. Before the onset of overt proteinuria, however, phosphorylation of both Y1204 and Y1228 rapidly decreased and became almost undetectable. During this period, the amount of F-actin in glomeruli began to decrease, whereas G-actin increased. Phosphorylation of nephrin at Y1228 in glomeruli of patients with minimal change nephrosis was significantly decreased compared with that in normal glomeruli. Our study suggests that tyrosine phosphorylation of nephrin by regulating F-actin formation may be important for the maintenance of normal podocyte morphology and function.


Assuntos
Actinas/metabolismo , Glomérulos Renais/metabolismo , Proteínas de Membrana/metabolismo , Nefrose/metabolismo , Proteínas Tirosina Quinases/metabolismo , Animais , Anticorpos/isolamento & purificação , Antimetabólitos Antineoplásicos/toxicidade , Células COS , Chlorocebus aethiops , Citoesqueleto/metabolismo , Humanos , Proteínas de Membrana/imunologia , Nefrose/induzido quimicamente , Fosforilação , Podócitos/metabolismo , Puromicina Aminonucleosídeo/toxicidade , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia
17.
Biochem Biophys Res Commun ; 356(1): 129-35, 2007 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-17346669

RESUMO

Maf is a family of transcription factor proteins that is characterized by a typical bZip structure, and one of the large mafs, mafA is a strong transactivator of insulin. To explore the role of mafA in the pancreas, we modified the mafA mRNA level in vivo in mice by the RNA interference (siRNA) technique and analyzed the resulting alteration of the expressed gene profile with a microarray system. The mafA expression level in siRNA-treated mice was reduced approximately 60% compared with control-siRNA-treated animals. Microarray analysis revealed changes in the expression level of several genes in the siRNA-treated mice, with prominent down-regulated expression of the genes encoding insulin, glucagon, and adipocytokines, suggesting possible role of mafA in the pathophysiological states of impaired metabolic responses or inflammatory reactions.


Assuntos
Perfilação da Expressão Gênica , Fatores de Transcrição Maf Maior/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Pancrelipase/metabolismo , Interferência de RNA , RNA Mensageiro/genética , Adiponectina/genética , Animais , Western Blotting , Fator D do Complemento/genética , Glucagon/genética , Injeções Intravenosas , Insulina/genética , Fatores de Transcrição Maf Maior/metabolismo , Masculino , Camundongos , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Biochem Biophys Res Commun ; 348(2): 501-6, 2006 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-16890189

RESUMO

Large mafs are transcriptional factors and members of the basic leucine zipper (b-Zip) superfamily. Since we previously identified expression of c-maf in mouse kidney, we presently investigated the mRNA expression profile in the kidney of c-maf gene knockout mice by using DNA microarray, and plasma glutathione peroxidase-3 (GPx3) was predominantly downregulated. We focused on the relation between the expression level of c-maf and GPx3 in vivo and in vitro. Since GPx3 is an antioxidant enzyme, oxidative stress was induced by exposing a culture cell derived from mouse renal tubules (mIMCD3) to hydrogen peroxide. Real-time PCR demonstrated that mRNA expression of both c-maf and GPx3 increased in parallel during exposure to oxidative stress in a time- and dose-dependent manner. Then, the mIMCD3 cells were transfected with c-maf-cDNA containing plasmid, which resulted in an increase in mRNA and protein expression of GPx3 compared with the control cells. Thus, c-maf may be transcriptional regulator of GPx3 expression and modulate the antioxidative pathway in the kidney.


Assuntos
Glutationa Peroxidase/biossíntese , Proteínas Proto-Oncogênicas c-maf/biossíntese , Animais , Células Cultivadas , Perfilação da Expressão Gênica , Peróxido de Hidrogênio/farmacologia , Rim/metabolismo , Túbulos Renais/citologia , Túbulos Renais/metabolismo , Camundongos , Camundongos Knockout , Estresse Oxidativo/fisiologia
19.
Kidney Int ; 70(2): 358-62, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16738534

RESUMO

Toll-like receptors (TLRs) play a pivotal role in pathogen recognition and subsequent cytokine synthesis by immune cells. Uremic patients have a high infectious morbidity, but it remains unclear if this arises from the defective innate immune responses related to TLRs. We studied TLR4 expression in monocytes and their intracellular cytokine synthesis in response to lipopolysaccharide (LPS) stimulation in 35 predialysis patients with chronic kidney disease (CKD) with or without predisposition to bacterial infections and 16 age-matched controls. Expression of TLR4 in unstimulated peripheral monocytes was determined by staining with anti-TLR4 antibody and analysis with flow cytometry. Monocytes were then stimulated by LPS, labeled with anti-CD14 antibody, and subjected to intracellular cytokine staining and flow cytometry. Tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, and IL-8 synthesis was examined in CD14(+) monocytes. TLR4 expression was constitutively diminished in CKD patients with reduced expression being more severe in those CKD patients who were predisposed to infections. Monocytes from these infection prone CKD patients exhibited significantly reduced synthesis of TNF-alpha, IL-1beta, IL-6, and IL-8 in response to LPS challenge compared with those from control subjects. The intensity of synthesis of each cytokine significantly correlated with TLR4 expression levels in monocytes (P<0.01). The capacity of monocytes to synthesize proinflammatory cytokines was significantly reduced in infection prone CKD patients, and this may possibly be due to the reduced monocyte expression of TLR4. Abnormal TLR4 expression by monocytes may play a role in the susceptibility of such patients to bacterial infections.


Assuntos
Citocinas/metabolismo , Monócitos/metabolismo , Receptor 4 Toll-Like/metabolismo , Uremia/imunologia , Uremia/metabolismo , Idoso , Infecções Bacterianas/imunologia , Infecções Bacterianas/metabolismo , Feminino , Citometria de Fluxo , Humanos , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Insuficiência Renal Crônica/imunologia , Insuficiência Renal Crônica/metabolismo
20.
Water Sci Technol ; 53(2): 215-24, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16594340

RESUMO

The atmospheric concentration and dry and wet deposition were measured for particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) from August to December in Higashi-Hiroshima City, Japan. PM concentration of fine particles (0.6-7 microm) was 5.7-75.1 micro m(-3), and coarse particles (> 7 microm) was 2.2-22.3 microg m(-3). Total PAHs concentration of fine particles was 0.14-16.3 ng m(-3), and coarse particles was 0.01-0.77 ng m(-3). Their concentration increased on non-rainy days and decreased rapidly on rainy days. For seasonal fluctuations of PAHs, their concentrations decreased from summer to winter, and the rate of decrease was more distinct for fine particles. For total (dry + wet) depositions, the PM flux was 1.9-11.2 mg m(-2) d(-1), and the total PAHs flux was 1.9-97.2 ng m(-3) d(-1). From these measurements, the yearly total loading of PAHs was estimated for the particle phase. Total loading was 28 microg m(-2) y(-1) for the dry deposition and 52 mg m(-2) y(-1) for the wet deposition. The loading of the wet deposition was comparable to those of the dry deposition for all ring numbers.


Assuntos
Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Movimentos do Ar , Poluentes Atmosféricos , Atmosfera , Meio Ambiente , Poluentes Ambientais , Japão , Chuva , Estações do Ano , Poluentes Químicos da Água
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