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1.
J Infect Chemother ; 28(12): 1667-1671, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36028210

RESUMO

BACKGROUND: Ceftazidime encephalopathy is reported to be caused by the repeated administration of ceftazidime in patients with renal impairment because of the high serum concentration of ceftazidime. Ceftazidime encephalopathy has been considered to be caused by the elevation of the cerebrospinal fluid (CSF) concentration. However, as no reports have measured CSF concentrations, the relationship with ceftazidime encephalopathy and CSF concentration has not been clarified. CASE PRESENTATION: Case 1: An 80-year-old Japanese man under a combination therapy with peritoneal dialysis and hemodialysis, who had been treated for a cellulitis with ceftazidime, developed altered consciousness and was diagnosed as ceftazidime encephalopathy. His serum concentration of ceftazidime was elevated, but CSF concentration was only under 0.1 µg/mL. Case 2: An 88-year-old Japanese man with chronic kidney disease, who had been treated for a urinary tract infection with ceftazidime, developed altered consciousness and was diagnosed as ceftazidime encephalopathy. His serum concentration of ceftazidime was elevated, but CSF concentration was within the therapeutic range. However, his serum and CSF concentration of quinolinic acid was markedly increased. CONCLUSIONS: Patients with renal failure are more likely to develop ceftazidime encephalopathy. We need to pay attention to the dosage of ceftazidime and to the appearance of neurological symptoms. Ceftazidime encephalopathy was considered to be caused by the high CSF concentration, but it could be caused by quinolinic acid as neurotoxic substance.


Assuntos
Encefalopatias , Diálise Peritoneal , Insuficiência Renal , Idoso de 80 Anos ou mais , Ceftazidima/efeitos adversos , Humanos , Masculino , Ácido Quinolínico
2.
J Public Health Afr ; 13(1): 2199, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35720794

RESUMO

High prevalence of anemia among children has been an important public health concern globally. In Zambia, the prevalence of anemia among children aged 6-59 months was 58%. Previous studies have suggested that feeding a variety of food prevents anemia. However, it is not yet determined if out of several food groups available locally, some foods have played crucial roles in anemia among young children. The objective of this study was to find out the food groups that were associated with childhood anemia among Zambian children aged 6-59 months. We have obtained the individual- level data related to health and nutrition of the Zambia Demographic Health Survey (ZDHS) 2018 with permission. Children's feeding, demographic, and household information were analyzed using logistic regression models. Children who consumed food made from grains (AOR:1.2; 95%CI: 1.01-1.46; p=0.044) and cheese or food made from milk (AOR:2.7; 95%CI: 1.19-6.00; p=0.018) showed relatively higher prevalence of anemia than those who did not. Additionally, malnutrition, mother's anemia and education, and area of living were also significantly associated with prevalence of anemia. Most common food in Zambia is food made from grain. Grain consists of phytic acids which can prevent iron absorption. This is a potential reason for the highlevel anemia among children. Dephytinization strategies should be considered through further studies.

3.
Intern Med ; 60(12): 1899-1906, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33456034

RESUMO

A 65-year-old man with valvular disorder presented to his physician because of widespread purpura in both lower extremities. Blood tests showed elevated serum creatinine levels and proteinase 3-anti-neutrophil cytoplasmic antibody (ANCA) with hematuria, suggesting ANCA-related rapidly progressive glomerulonephritis (RPGN). Although multiple blood cultures were negative, transthoracic echocardiography revealed warts in the valves, and a renal biopsy also showed findings of glomerular infiltration by mononuclear leukocytes and C3 deposition in the glomeruli, suggesting infection-related glomerulonephritis. Later, Bartonella antibody turned positive. Antimicrobial treatment improved the purpura and renal function without any recurrence. ANCA-positive RPGN requires the exclusion of infective endocarditis, especially that induced by Bartonella spp.


Assuntos
Bartonella , Endocardite Bacteriana , Endocardite , Glomerulonefrite , Idoso , Anticorpos Anticitoplasma de Neutrófilos , Endocardite/diagnóstico por imagem , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/tratamento farmacológico , Glomerulonefrite/diagnóstico , Humanos , Masculino
4.
Intern Med ; 58(1): 31-38, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30101942

RESUMO

Objective This case series aimed to identify the clinical and pathological characteristics of elderly patients (≥60 years) with biopsy-proven IgA vasculitis with nephritis (IgAVN). Methods The clinical and pathological presentation and treatment outcomes were compared between two groups. Patients Patients with IgAVN who were ≥19 years old at the time of their renal biopsy were divided into elderly (≥60 years) and adult (19-59 years) groups. Results Of the 23 patients in our study, 13 were elderly. In the elderly group, the median age at the diagnosis was 68 years (range, 60-85 years), with a median follow-up period of 15 months (range, 3-80 months). Twelve elderly patients had comorbidities, including hypertension, diabetes mellitus, chronic kidney disease, cardiovascular disease, and malignancies. A decrease in the estimated glomerular filtration rate, as well as massive proteinuria and rapidly progressive nephritic syndrome, were more frequent in the elderly group than in the adult group. Furthermore, renal pathological changes, including cellular or fibrocellular crescents, interstitial fibrosis, tubular atrophy, and arteriosclerosis, were more severe among elderly patients than adult patients. All elderly patients were treated with glucocorticoids and had no incidence of end-stage renal disease at the final follow-up; in addition, nine elderly patients had reduced proteinuria with a preserved renal function. Adverse events, including infection, diabetes mellitus, and vascular disorders, were identified in nine patients. Three elderly patients died from severe infections. Conclusion IgAVN in elderly patients is characterized by severe renal involvement. Elderly patients are at higher risk than adults for treatment-related adverse events.


Assuntos
Imunoglobulina A , Nefrite/etiologia , Nefrite/patologia , Vasculite/etiologia , Vasculite/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Taxa de Filtração Glomerular , Glucocorticoides/uso terapêutico , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Nefrite/terapia , Resultado do Tratamento , Vasculite/complicações , Vasculite/terapia , Adulto Jovem
5.
J Neurochem ; 147(2): 153-177, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30151872

RESUMO

Cytohesin-2 is a member of the guanine nucleotide exchange factors for ADP ribosylation factor 1 (Arf1) and Arf6, which are small GTPases that regulate membrane traffic and actin dynamics. In this study, we first demonstrated that cytohesin-2 localized to the plasma membrane and vesicles in various subcellular compartment in hippocampal neurons by immunoelectron microscopy. Next, to understand the molecular network of cytohesin-2 in neurons, we conducted yeast two-hybrid screening of brain cDNA libraries using cytohesin-2 as bait and isolated pallidin, a component of the biogenesis of lysosome-related organelles complex 1 (BLOC-1) involved in endosomal trafficking. Pallidin interacted specifically with cytohesin-2 among cytohesin family members. Glutathione S-transferase pull-down and immunoprecipitation assays further confirmed the formation of a protein complex between cytohesin-2 and pallidin. Immunofluorescence demonstrated that cytohesin-2 and pallidin partially colocalized in various subsets of endosomes immunopositive for EEA1, syntaxin 12, and LAMP2 in hippocampal neurons. Knockdown of pallidin or cytohesin-2 reduced cytoplasmic EEA1-positive early endosomes. Furthermore, knockdown of pallidin increased the total dendritic length of cultured hippocampal neurons, which was rescued by co-expression of wild-type pallidin but not a mutant lacking the ability to interact with cytohesin-2. In contrast, knockdown of cytohesin-2 had the opposite effect on total dendritic length. The present results suggested that the interaction between pallidin and cytohesin-2 may participate in various neuronal functions such as endosomal trafficking and dendritic formation in hippocampal neurons. Cover Image for this issue: doi: 10.1111/jnc.14197.


Assuntos
Proteínas de Transporte/fisiologia , Dendritos/fisiologia , Endossomos/fisiologia , Proteínas Ativadoras de GTPase/fisiologia , Lectinas/fisiologia , Neurônios/fisiologia , Animais , Proteínas de Transporte/genética , Membrana Celular/metabolismo , Células Cultivadas , Vesículas Citoplasmáticas/metabolismo , Dendritos/ultraestrutura , Endossomos/genética , Proteínas Ativadoras de GTPase/genética , Técnicas de Silenciamento de Genes , Glutationa Transferase/metabolismo , Células HeLa , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Lectinas/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação/genética , Neurônios/ultraestrutura
6.
PLoS One ; 10(3): e0118965, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25742311

RESUMO

Leaf tissues of plants usually contain several types of idioblasts, defined as specialized cells whose shape and contents differ from the surrounding homogeneous cells. The spatial patterning of idioblasts, particularly of trichomes and guard cells, across the leaf epidermis has received considerable attention as it offers a useful biological model for studying the intercellular regulation of cell fate and patterning. Excretory idioblasts in the leaves of the aquatic monocotyledonous plant Egeria densa produced light blue autofluorescence when irradiated with ultraviolet light. The use of epifluorescence microscopy to detect this autofluorescence provided a simple and convenient method for detecting excretory idioblasts and allowed tracking of those cells across the leaf surfaces, enabling quantitative measurement of the clustering and spacing patterns of idioblasts at the whole leaf level. Occurrence of idioblasts was coordinated along the proximal-distal, medial-lateral, and adaxial-abaxial axes, producing a recognizable consensus spatial pattern of idioblast formation among fully expanded leaves. Idioblast clusters, which comprised up to nine cells aligned along the proximal-distal axis, showed no positional bias or regularity in idioblast-forming areas when compared with singlet idioblasts. Up to 75% of idioblasts existed as clusters on every leaf side examined. The idioblast-forming areas varied between leaves, implying phenotypic plasticity. Furthermore, in young expanding leaves, autofluorescence was occasionally detected in a single giant vesicle or else in one or more small vesicles, which eventually grew to occupy a large portion of the idioblast volume as a central vacuole. Differentiation of vacuoles by accumulating the fluorescence substance might be an integral part of idioblast differentiation. Red autofluorescence from chloroplasts was not detected in idioblasts of young expanding leaves, suggesting idioblast differentiation involves an arrest in chloroplast development at a very early stage, rather than transdifferentiation of chloroplast-containing epidermal cells.


Assuntos
Cloroplastos/metabolismo , Hydrocharitaceae/metabolismo , Folhas de Planta/metabolismo , Vacúolos/metabolismo , Hydrocharitaceae/crescimento & desenvolvimento
7.
Nihon Jinzo Gakkai Shi ; 54(5): 615-21, 2012.
Artigo em Japonês | MEDLINE | ID: mdl-22991842

RESUMO

A 76-year-old man was admitted to our hospital because of severe anemia. Routine screening revealed a sigmoid adenocarcinoma, and he underwent sigmoidectomy. Post-operatively, he developed rapidly progressive glomerulonephritis. He was positive for myeloperoxidase anti-neutrophil cytoplasmic antibody. A renal biopsy revealed idiopathic crescentic glomerulonephritis of the pauci-immune type. He was treated with methylprednisolone semi-pulse therapy with clinical improvement. After the steroid pulse therapy, he was given oral prednisolone, 40 mg per day, and oral trimethoprim (TMP), 160 mg, and sulfamethoxazole (SMX), 800 mg twice weekly for chemoprophylaxis against pneumocystis pneumonia. One month after the initiation of TMP/SMX, he developed hyperkalemia and hyponatremia. His transtubular K gradient was low, and urinary potassium excretion was decreased. On the other hand, plasma renin activity and plasma aldosterone concentrations were within normal limits. These results suggested that TMP acted similarly to a potassium-sparing diuretic amiloride and reduced renal potassium excretion. Administration of calcium polystyrene sulfonate resulted in correction of the hyperkalemia without discontinuation of TMP/SMX. We emphasize that patients with impaired renal function are at the significant risk of developing trimethoprim-induced hyperkalemia even with chemoprophylaxis.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Antibioticoprofilaxia , Hiperpotassemia/induzido quimicamente , Hospedeiro Imunocomprometido , Pneumonia Pneumocócica/prevenção & controle , Complicações Pós-Operatórias , Combinação Trimetoprima e Sulfametoxazol/efeitos adversos , Adenocarcinoma/cirurgia , Idoso , Glomerulonefrite , Humanos , Masculino , Neoplasias do Colo Sigmoide/cirurgia , Combinação Trimetoprima e Sulfametoxazol/administração & dosagem
8.
Bioorg Med Chem ; 15(3): 1475-82, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17110116

RESUMO

We have synthesized four new geometric isomers of 1alpha,25-dihydroxy-2-(2'-fluoroethylidene)-19-norvitamin D analogs 1 and 2 having a 20R- and 20S-configuration, whose structures are correlated with 2MD possessing high potencies in stimulating bone formation in vitro and in vivo. The E-isomers of (20R)- and (20S)-2-fluoroethylidene analogs 1a and 1b were comparable with the natural hormone 1alpha,25-(OH)(2)D(3) in binding to the vitamin D receptor (VDR), while two Z-isomers 2a and 2b were about 15-20 times less active than the hormone. In inducing expression of the vitamin D responsive element-based luciferase reporter gene, the E-isomers 1a and 1b were 1.2- and 8.6-fold more potent than the hormone, respectively, while the Z-isomers 2a and 2b had 27-55% of the potency. On the basis of the biological activities and a docking simulation based on X-ray crystallographic analysis of the VDR ligand-binding pocket, the structure-activity relationships of the fluorinated 19-norvitamin D analogs are discussed.


Assuntos
Calcitriol/análogos & derivados , Calcitriol/farmacologia , Receptores de Calcitriol/metabolismo , Animais , Sítios de Ligação , Células COS/efeitos dos fármacos , Calcitriol/síntese química , Calcitriol/química , Chlorocebus aethiops , Camundongos , Osteopontina/genética , Osteopontina/metabolismo , Ligação Proteica , Ratos , Receptores de Calcitriol/genética , Relação Estrutura-Atividade , Transcrição Gênica , Compostos de Vinila/química , Elemento de Resposta à Vitamina D/genética
9.
Bone ; 40(2): 293-304, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17070129

RESUMO

2-Methylene-19-nor-(20S)-1alpha,25-dihydroxyvitamin D3 (2MD), an analog of 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3], has been shown to strongly induce bone formation both in vitro and in vivo. We have synthesized four substituents at carbon 2 of 2MD (2MD analogs), four stereoisomers at carbon 20 of the respective 2MD analogs (2MD analog-C20 isomers) and four 2MD analogs with an oxygen atom at carbon 22 (2MD-22-oxa analogs) and examined their ability to stimulate osteoclastogenesis and induce hypercalcemia. 2MD analogs were 100 times as potent as 1alpha,25(OH)2D3 in stimulating the formation of osteoclasts in vitro and in inducing the expression of receptor activator of NF-kappaB ligand (RANKL) and 25-hydroxyvitamin D3-24 hydroxylase mRNAs in osteoblasts. The osteoclast-inducing activities of 2MD analog-C20 isomers and 2MD 22-oxa analogs were much weaker than those of 2MD analogs. In addition, the activity of a 2MD analog in inducing dentine resorption was much stronger than that of 1alpha,25(OH)2D3 in the pit formation assay. Affinities to the vitamin D receptor and transcriptional activities of these compounds did not always correlate with their osteoclastogenic activities. Osteoprotegerin-deficient (OPG-/-) mice provide a suitable model for investigating in vivo effects of 2MD analogs because they exhibit extremely high concentrations of serum RANKL. The same amounts of 2MD analogs and 1alpha,25(OH)2D3 were administered daily to OPG-/- mice for 2 days. The elevation in serum concentrations of RANKL and calcium was much greater in 2MD analog-treated OPG-/- mice than in 1alpha,25(OH)2D3-treated ones. A 2MD analog was much more potent than 1alpha,25(OH)2D3 in causing hypercalcemia and in increasing soluble RANKL with enhanced osteoclastogenesis even in wild-type mice. In contrast, the administration of the 2MD analog to c-fos-deficient mice failed to induce osteoclastogenesis and hypercalcemia. These results suggest that new substituents at carbon 2 of 2MD strongly stimulate osteoclast formation in vitro and in vivo, and that osteoclastic bone resorption is indispensable for their hypercalcemic action of 2MD analogs in vivo.


Assuntos
Calcitriol/análogos & derivados , Osteoclastos/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Calcitriol/química , Calcitriol/farmacologia , Células Cultivadas , Hipercalcemia/metabolismo , Hipercalcemia/patologia , Masculino , Camundongos , Camundongos Knockout , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoclastos/fisiologia , Osteoprotegerina/genética , Proteínas Proto-Oncogênicas c-fos/genética , Ligante RANK/biossíntese , RNA Mensageiro/biossíntese , Receptores de Calcitriol/metabolismo , Esteroide Hidroxilases/biossíntese , Esteroide Hidroxilases/genética , Relação Estrutura-Atividade , Vitamina D3 24-Hidroxilase
10.
Bioorg Med Chem ; 14(12): 4277-94, 2006 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-16503143

RESUMO

In a series of studies on structure-activity relationships of 2-substituted 19-norvitamin D analogs, we found that 1alpha,25-dihydroxy-19-norvitamin D3 analogs with 2beta-hydroxyethoxy or 2E-hydroxyethylidene moieties show strong binding affinity for the vitamin D receptor (VDR) as well as marked transcriptional activity. To further examine the effects of side chain structure on the activity of 2-substituted 19-norvitamin D analogs, we have synthesized new 19-norvitamin D3 analogs with modifications in both the A-ring at the C(2) position and the side chain. The side chains of these analogs contained a double bond between C(22) and C(23) or an oxygen atom at C(22). The biological activity of the analogs was evaluated in vitro. All the side chain-modified analogs were less active than 1alpha,25-dihydroxyvitamin D31e and the parent compounds 3-6e possessing a natural 20R-configuration in binding to the VDR, but, except for the (20R)-22-oxa analogs 3-6d, were significantly more potent in transcriptional activity. Of the side-chain-modified analogs 4 and 5, the 2beta-hydroxyethoxy- and 2E-hydroxyethylidene-22,24-diene-24a,26a,27a-trihomo analogs showed markedly higher transcriptional activity (25- and 17.5-fold, respectively) compared with 1e. Elongation of the side chain at the C-24, C-26, and C-27 positions and introduction of a 22,24-diene moiety strongly increased transcriptional activity, as seen in the 20-epi analogs 3-6f.


Assuntos
Calcitriol/análogos & derivados , Receptores de Calcitriol/efeitos dos fármacos , Animais , Sítios de Ligação , Células COS , Calcitriol/síntese química , Calcitriol/química , Calcitriol/farmacologia , Chlorocebus aethiops , Avaliação Pré-Clínica de Medicamentos , Técnicas In Vitro , Ligantes , Conformação Molecular , Ratos , Estereoisomerismo , Relação Estrutura-Atividade , Transcrição Gênica/efeitos dos fármacos
11.
Bioorg Med Chem ; 12(22): 5799-806, 2004 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15498656

RESUMO

Our previous study has shown that alpha-mangostin, a xanthone from the pericarps of mangosteen, induces caspase-3-dependent apoptosis in HL60 cells. In the current study, we investigated the mechanism of apoptosis induced by alpha-mangostin in HL60 cells. Alpha-mangostin-treated HL60 cells demonstrated caspase-9 and -3 activation but not -8, which leads us to assume that alpha-mangostin may mediate the mitochondrial pathway in the apoptosis. Parameters of mitochondrial dysfunction including swelling, loss of membrane potential (deltapsim), decrease in intracellular ATP, ROS accumulation, and cytochrome c/AIF release, were observed within 1 or 2 h after the treatment. On the other hand, alpha-mangostin-treatment did not affect expression of bcl-2 family proteins and activation of MAP kinases. These findings indicate that alpha-mangostin preferentially targets mitochondria in the early phase, resulting in indication of apoptosis in HL60 cells. Furthermore, we examined the structure-activity relationship between xanthone derivatives including alpha-mangostin and the potency of deltapsim-loss in HL60 cells. Interestingly, replacement of hydroxyl group by methoxy group remarkably decreased its potency. It was also shown that the cytotoxicity substantially correlated with deltapsim decrease. These results indicate that alpha-mangostin and its analogs would be candidates for preventive and therapeutic application for cancer treatment.


Assuntos
Apoptose/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Mitocôndrias/efeitos dos fármacos , Xantonas/administração & dosagem , Apoptose/fisiologia , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HL-60 , Humanos , Mitocôndrias/fisiologia , Xantonas/química
12.
FEBS Lett ; 563(1-3): 69-74, 2004 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-15063725

RESUMO

An important component of the extracellular matrix is the group of non-collagenous proteins belonging to the small leucine-rich repeat (SLR) protein family. A new SLR protein, podocan, with structural characteristics different from the known classes of the SLR protein family has been identified recently from the kidney. In this study, we examined the functional characteristics of this SLR protein expressed in cultured cells. Podocan was clearly observed intracellularly and was also detectable in the supernatant. Treatment of the expressed protein with various glycoenzymes suggested that podocan is a glycoprotein containing N-linked oligosaccharides but not a classical proteoglycan. Moreover, podocan was found to bind type 1 collagen. Cells transfected with podocan showed reductions in cell growth and migration, concomitant with increased p21 expression. Podocan mRNA was detected by reverse transcription polymerase chain reaction not only in the kidney, but also in other tissues including the heart and vascular smooth muscle cells, suggesting that podocan may have a potential role in growth regulation in cardiovascular tissues.


Assuntos
Proteínas , Proteínas/metabolismo , Animais , Células CHO , Células COS , Divisão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Chlorocebus aethiops , Colágeno Tipo I/metabolismo , Cricetinae , Cricetulus , Perfilação da Expressão Gênica , Glicoproteínas , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas de Repetições Ricas em Leucina , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Proteínas/química , Proteínas/classificação , Proteínas/genética , Proteínas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Proteínas Recombinantes de Fusão/metabolismo , Sequências Repetitivas de Aminoácidos , Distribuição Tecidual
13.
Circ Res ; 94(8): 1067-74, 2004 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-15031262

RESUMO

Proteoglycans are produced and secreted by vascular smooth muscle cells, but the pathophysiological role of these glycoproteins in the vasculature is an enigma. Because the small leucine-rich proteoglycan (SLRP) biglycan is overexpressed in arteriosclerotic lesions, we produced mice constitutively overexpressing biglycan in the vascular smooth muscle, in order to examine the effects on vascular pathology. In the aorta and renal vasculature, increased vascular proliferation was seen both in the basal state and after infusion of angiotensin II (Ang II) in the transgenic mice compared with wild-type controls. In addition, the combination of biglycan overexpression and Ang II infusion resulted in marked increases in vascular smooth muscle cell proliferation and migration in the coronary arteries, as well as increases in fibrosis surrounding the vessels. In vitro, biglycan caused an increase in thymidine incorporation and migration of vascular smooth muscle cells, whereas these parameters were unchanged or reduced in endothelial cells. Moreover, addition of biglycan resulted in an increase in cdk2 expression and decrease in p27 levels in the vascular smooth muscle cells. These results suggest that this extracellular matrix SLRP may be involved in the regulation of vascular smooth muscle growth and migration through cdk2- and p27-dependent pathways. Furthermore, changes in biglycan expression could be a factor influencing the susceptibility of arteries to vascular injury, and may play a direct role in the pathogenesis of vascular lesions.


Assuntos
Arteriopatias Oclusivas/etiologia , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Proteoglicanas/fisiologia , Actinas/genética , Angiotensina II/genética , Angiotensina II/farmacologia , Animais , Aorta/metabolismo , Aorta/ultraestrutura , Arteriopatias Oclusivas/genética , Arteriopatias Oclusivas/metabolismo , Arteriopatias Oclusivas/patologia , Arteríolas/metabolismo , Arteríolas/ultraestrutura , Biglicano , Quinases relacionadas a CDC2 e CDC28/genética , Quinases relacionadas a CDC2 e CDC28/fisiologia , Bovinos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/fisiologia , Divisão Celular , Movimento Celular , Células Cultivadas/citologia , Células Cultivadas/metabolismo , Vasos Coronários/metabolismo , Vasos Coronários/ultraestrutura , Quinase 2 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p27 , Suscetibilidade a Doenças , Células Endoteliais/citologia , Proteínas da Matriz Extracelular , Regulação da Expressão Gênica , Humanos , Rim/irrigação sanguínea , Masculino , Camundongos , Camundongos Transgênicos , Músculo Liso Vascular/lesões , Miócitos de Músculo Liso/fisiologia , Especificidade de Órgãos , Regiões Promotoras Genéticas/genética , Proteoglicanas/biossíntese , Proteoglicanas/genética , Ratos , Ratos Wistar , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/fisiologia , Renina/sangue , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/fisiologia
14.
Kidney Int ; 64(4): 1179-88, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12969135

RESUMO

BACKGROUND: Hepatocyte growth factor (HGF) is a clinically important growth factor with therapeutic potential for the treatment of interstitial fibrosis and chronic renal failure. Proteoglycans are components of the renal interstitium, which have multiple actions, including growth regulation. In this study, we examined the effects of HGF on proteoglycan synthesis in interstitial fibroblasts, and the mechanisms of these effects. METHODS AND RESULTS: Expression and agonist-induced activation of the HGF receptor c-Met was detected in rat renal interstitial fibroblasts (NRK-49F) by reverse transcription-polymerase chain reaction (RT-PCR) analysis and immune complex/immunoblot assay. Moreover, stimulation of the cells with HGF resulted in a marked increase (five- to tenfold) in phosphorylation of extracellular signal-related protein kinase (ERK) 1/2 and p38 mitogen-activated protein kinase (MAPK), but not of c-Jun NH2 terminal kinase (JNK). Treatment with HGF resulted in a time- and dose-dependent increase (P < 0.01) in both cell-associated and secreted proteoglycan synthesis to two- to fourfold of control levels. This effect was attenuated by the MAPK/ERK kinase (MEK) inhibitor PD98059 and the p38 MAPK inhibitor SB203580. Ion-exchange chromatography suggested that chondroitin sulfate/dermatan sulfate proteoglycans were up-regulated after HGF treatment. Northern blot, RT-PCR, Western blot, and promoter activity assays revealed that HGF caused a significant increase in decorin mRNA and protein, as well as in biglycan mRNA, protein, and promoter activity, suggesting transcriptional control of gene expression. Since the effects of biglycan on fibroblast proliferation are still unclear, the effects of biglycan were examined by thymidine assay, and biglycan was found to attenuate transforming growth factor-beta (TGF-beta)-induced changes in cell proliferation. CONCLUSION: These results suggest that HGF causes an increase in the small leucine-rich proteoglycans biglycan and decorin by ERK1/2- and p38 MAPK-mediated pathways in fibroblasts. These findings may be relevant for understanding potential mechanisms by which HGF can exert TGF-beta inhibitory actions in the kidney.


Assuntos
Proteínas da Matriz Extracelular , Fibroblastos/metabolismo , Fator de Crescimento de Hepatócito/fisiologia , Rim/metabolismo , Proteoglicanas/biossíntese , Agrecanas , Animais , Biglicano , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Fibroblastos/citologia , Glicoproteínas/metabolismo , Fator de Crescimento de Hepatócito/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno , Rim/citologia , Lectinas Tipo C , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Proteoglicanas/farmacologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Proteínas Proto-Oncogênicas c-met/fisiologia , Ratos , Fator de Crescimento Transformador beta/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno
15.
J Nat Prod ; 66(8): 1124-7, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12932141

RESUMO

We examined the effects of six xanthones from the pericarps of mangosteen, Garcinia mangostana, on the cell growth inhibition of human leukemia cell line HL60. All xanthones displayed growth inhibitory effects. Among them, alpha-mangostin showed complete inhibition at 10 microM through the induction of apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Garcinia/química , Plantas Medicinais/química , Xantonas/isolamento & purificação , Western Blotting , Células HL-60/efeitos dos fármacos , Humanos , Indonésia , Concentração Inibidora 50 , Leucemia , Estrutura Molecular , Estereoisomerismo , Células Tumorais Cultivadas/efeitos dos fármacos , Xantonas/química , Xantonas/farmacologia
16.
Biol Pharm Bull ; 26(4): 569-71, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12673047

RESUMO

We examined the in vitro effects of the benzophenone derivatives garcinol, isogarcinol, and xanthochymol on cell growth in four human leukemia cell lines. All of the compounds exhibited significant growth suppression due to apoptosis mediated by the activation of caspase-3. A loss of mitochondrial membrane potential was found in garcinol- and isogarcinol-induced apoptosis, but not in xanthochymol-induced apoptosis. The growth inhibitory effects of isogarcinol and xanthochymol were more potent than that of garcinol, which is a well- known cytotoxic benzophenone derivative.


Assuntos
Apoptose/efeitos dos fármacos , Benzofenonas/toxicidade , Citotoxinas/toxicidade , Garcinia , Leucemia/patologia , Apoptose/fisiologia , Benzofenonas/isolamento & purificação , Contagem de Células/métodos , Linhagem Celular Tumoral , Citotoxinas/isolamento & purificação , Células HL-60 , Humanos , Células K562 , Células U937
17.
Kidney Int ; 62(3): 780-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12164860

RESUMO

BACKGROUND: Proteoglycans are integral components of the mesangial matrix and glomerular permeability barrier. Recent studies have shown that changes in glomerular proteoglycan expression may play a major role in the pathogenesis of renal disease. Steroid hormones are used as first-choice therapy for the treatment of glomerular diseases, however, the effects of glucocorticoids on expression of glomerular proteoglycans are unknown. METHODS: This study examined the effects of in vitro and in vivo administration of dexamethasone on proteoglycan synthesis and gene expression of proteoglycan core proteins using rat (RMC) and human (HMC) mesangial cells. RESULTS: Treatment of cultured RMC with dexamethasone resulted in a dose- and time-dependent decrease (P < 0.05) in both cell-associated and secreted proteoglycan synthesis to approximately 50% of control levels. This effect was inhibited by the glucocorticoid antagonist mifepristone, and mimicked by prednisolone or corticosterone treatment. Separation of proteoglycans by ion-exchange and gel permeation chromatography suggested that chondroitin sulfate/dermatan sulfate proteoglycans were down-regulated after steroid treatment. Northern blot analysis, RT-PCR, Western blot, and promoter activity assays revealed that dexamethasone caused a significant decrease in decorin mRNA (to 61 +/- 8% of controls), whereas biglycan expression and promoter activity were increased after steroid treatment. A similar trend was found in glomeruli isolated from rats treated in vivo with dexamethasone. CONCLUSIONS: These results demonstrate that treatment of mesangial cells with steroids results in a decrease in total proteoglycan synthesis, as well as subtype-specific changes in proteoglycan core protein gene expression by transcriptional control, furthering our understanding of the effects of steroid treatment on the renal glomeruli.


Assuntos
Dexametasona/farmacologia , Proteínas da Matriz Extracelular , Mesângio Glomerular/fisiologia , Glucocorticoides/farmacologia , Glicoproteínas/genética , Agrecanas , Animais , Biglicano , Células Cultivadas , Decorina , Expressão Gênica/efeitos dos fármacos , Mesângio Glomerular/química , Mesângio Glomerular/citologia , Glicoproteínas/análise , Humanos , Lectinas Tipo C , Masculino , Regiões Promotoras Genéticas/efeitos dos fármacos , Proteoglicanas/genética , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley
18.
Artigo em Inglês | MEDLINE | ID: mdl-12755260

RESUMO

Venous blood treated with magnesium sulphate (MgSO4) at blood collection was used for hematology tests. Complete blood counts and automated leukocyte differentials were obtained using a hematology analyzer, and the results obtained for blood treated with MgSO4 were similar to those for blood treated with dipotassium ethylenediaminetetraacetic acid (EDTA K2). Coagulation tests such as activated partial thromboplastin time, platelet factor 3 availability and prothrombin time were dose-dependently affected by the use of MgSO4. Thrombin time was prolonged by addition of MgSO4, and fibrin concentrations determined by coagulometry tended to decrease with addition of MgSO4, although fibrin concentrations determined by the weighing method were unaffected by MgSO4. MgSO, was thus found to potently inhibit blood coagulation and can be used as an anticoagulant for hematology tests.


Assuntos
Anticoagulantes , Testes de Coagulação Sanguínea/métodos , Hematologia/instrumentação , Sulfato de Magnésio , Contagem de Células Sanguíneas/métodos , Coagulação Sanguínea/efeitos dos fármacos , Ácido Edético , Humanos
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