Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Nucl Med Commun ; 41(10): 1081-1088, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32732603

RESUMO

PURPOSE: F-fluorodeoxiglucose (F-FDG)-PET/CT has been widely used to evaluate multiple myeloma. Tc-sestamibi (MIBI) scintigraphy has also been proposed for assessing multiple myeloma, but its use with state-of-the-art single-photon emission computed tomography/computed tomography (SPECT/CT) technology has not been fully evaluated.This study aimed to compare these two imaging modalities in multiple myeloma staging. MATERIALS AND METHODS: Sixty-two patients with recently diagnosed multiple myeloma were submitted to whole-body F-FDG-PET/CT and whole-body MIBI scans plus SPECT/CT of the chest and abdomen/pelvis. Number of focal lesions, contiguous soft tissue involvement (CSTI), extramedullary lesions (EMLs) and diffuse bone marrow (BM) involvement were recorded. RESULTS: PET/CT was positive in 59 patients (95%) and MIBI SPECT/CT in 58 (93%) (P = 0.69). MIBI detected more diffuse bone marrow involvement than PET/CT (respectively 78 vs. 58% of the patients), while PET/CT demonstrated more focal lesions than MIBI SPECT/CT (81 vs. 54% of the patients) (P = 0.002). PET/CT detected EMLs in four subjects and MIBI in one subject. CSTI was found in 28 (45%) and 23 (37%) patients on PET/CT and MIBI images, respectively (P = 0.36). Three patients with lytic lesions and no FDG uptake were MIBI positive, and two subjects with lytic lesions without MIBI uptake were FDG positive. CONCLUSION: MIBI SPECT/CT performs similarly to F-FDG-PET/CT in identifying sites of active disease in multiple myeloma staging. MIBI is more efficient than FDG for detecting the diffuse involvement of bone marrow but less efficient for detecting focal lesions. Some patients presented a 'mismatch' pattern of FDG/MIBI uptake.


Assuntos
Fluordesoxiglucose F18 , Mieloma Múltiplo/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tecnécio Tc 99m Sestamibi , Adulto , Idoso , Transporte Biológico , Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/metabolismo
2.
World J Gastroenterol ; 24(18): 1995-2008, 2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-29760543

RESUMO

AIM: To investigate the effect of probiotic supplementation during the development of an experimental model of colitis associated colon cancer (CAC). METHODS: C57BL/6 mice received an intraperitoneal injection of azoxymethane (10 mg/kg), followed by three cycles of sodium dextran sulphate diluted in water (5% w/v). Probiotic group received daily a mixture of Lactobacillus acidophilus, Lactobacillus rhamnosus and Bifidobacterium bifidum. Microbiota composition was assessed by 16S rRNA Illumina HiSeq sequencing. Colon samples were collected for histological analysis. Tumor cytokines was assessed by Real Time-PCR (Polymerase Chain Reaction); and serum cytokines by Multiplex assay. All tests were two-sided. The level of significance was set at P < 0.05. Graphs were generated and statistical analysis performed using the software GraphPad Prism 5.0. The project was approved by the institutional review board committee. RESULTS: At day 60 after azoxymethane injection, the mean number of tumours in the probiotic group was 40% lower than that in the control group, and the probiotic group exhibited tumours of smaller size (< 2 mm) (P < 0.05). There was no difference in richness and diversity between groups. However, there was a significant difference in beta diversity in the multidimensional scaling analysis. The abundance of the genera Lactobacillus, Bifidobacterium, Allobaculum, Clostridium XI and Clostridium XVIII increased in the probiotic group (P < 0.05). The microbial change was accompanied by reduced colitis, demonstrated by a 46% reduction in the colon inflammatory index; reduced expression of the serum chemokines RANTES and Eotaxin; decreased p-IKK and TNF-α and increased IL-10 expression in the colon. CONCLUSION: Our results suggest a potential chemopreventive effect of probiotic on CAC. Probiotic supplementation changes microbiota structure and regulates the inflammatory response, reducing colitis and preventing CAC.


Assuntos
Colite/patologia , Neoplasias do Colo/prevenção & controle , Microbioma Gastrointestinal/fisiologia , Probióticos/uso terapêutico , Animais , Azoximetano/toxicidade , Bifidobacterium/fisiologia , Colite/sangue , Colite/induzido quimicamente , Colite/microbiologia , Colo/microbiologia , Colo/patologia , Neoplasias do Colo/sangue , Neoplasias do Colo/microbiologia , Neoplasias do Colo/patologia , Citocinas/análise , Modelos Animais de Doenças , Humanos , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Lactobacillus acidophilus/fisiologia , Lacticaseibacillus rhamnosus/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Ribossômico 16S/isolamento & purificação
3.
Arq Bras Endocrinol Metabol ; 51(2): 195-203, 2007 Mar.
Artigo em Português | MEDLINE | ID: mdl-17505626

RESUMO

Insulin (Ins) and angiotensin II (AII) play pivotal roles in the control of two vital and closely related systems: the metabolic and the circulatory, respectively. A failure in the proper action of each of these hormones results, to a variable degree, in the development of two highly prevalent and commonly overlapping diseases--diabetes mellitus (DM) and hypertension (AH). In recent years, a series of studies has revealed a tight connection between the signal transduction pathways that mediate Ins and AII actions in target tissues. This molecular cross-talk occurs at multiple levels and plays an important role in phenomena that range from the action of anti-hypertensive drugs to cardiac hypertrophy and energy acquisition by the heart. At the extracellular level, the angiotensin-converting enzyme controls AII synthesis but also interferes with Ins signaling through the proper regulation of AII and the accumulation of bradykinin. At an early intracellular level, AII, acting through JAK-2/IRS-1/PI3-kinase, JNK and ERK, may induce the serine phosphorylation and inhibition of key elements of the Ins-signaling pathway. Finally, by inducing the expression of the regulatory protein SOCS-3, AII may impose a late control on the Ins signal. This review will focus on the main advances obtained in this field and will discuss the implications of this molecular cross-talk in the common clinical association between DM and AH.


Assuntos
Angiotensina II/fisiologia , Diabetes Mellitus/fisiopatologia , Hipertensão/fisiopatologia , Resistência à Insulina/fisiologia , Insulina/fisiologia , Transdução de Sinais/fisiologia , Animais , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/fisiologia
4.
FEBS Lett ; 535(1-3): 17-22, 2003 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-12560071

RESUMO

In the present study we used K562 cells to demonstrate that insulin receptor substrate 1 (IRS-1) is expressed and constitutively phosphorylated in BCR-ABL(+) cells. We observed association between BCR-ABL/IRS-1, IRS-1/phosphoinositide 3'-kinase (PI3-kinase), and IRS-1/Grb2 in the K562 cell line. Our findings demonstrate that imatinib treatment resulted in marked attenuation of BCR-ABL/IRS-1 association and of IRS-1-stimulated PI3-kinase activity in K562 cells. We concluded that the IRS-1 protein is involved in the signalling pathway of the BCR-ABL tyrosine kinase.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Fusão bcr-abl/metabolismo , Fosfoproteínas/metabolismo , Piperazinas/farmacologia , Pirimidinas/farmacologia , Benzamidas , Western Blotting , Relação Dose-Resposta a Droga , Ativação Enzimática/fisiologia , Inibidores Enzimáticos/farmacologia , Proteína Adaptadora GRB2 , Células HL-60 , Humanos , Mesilato de Imatinib , Proteínas Substratos do Receptor de Insulina , Células K562 , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Proteínas/metabolismo
5.
Brain Res Bull ; 57(5): 613-8, 2002 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11927363

RESUMO

The role of the central nervous system (CNS) in the control of hydrosaline homeostasis has been strikingly demonstrated by several studies. Growing evidence suggests that insulin may exert an influence in the modulation of many brain functions. However, there are no available data examining the CNS effect of insulin injection on renal sodium handling. Also, to examine the influence of renal nerve activity during i.c.v. administration of insulin, unanesthetized, unrestrained rats were randomly assigned to one of nine separated groups: (a) sham-operated i.c.v. 0.15 M NaCl-injected (Co, pooled data, n = 37) and sham-operated i.c.v. 0.42 ng. microl(-1) (n = 12), 4.2 ng.microl(-1) (n = 10) and 42.0 ng.microl(-1) (n = 11) insulin-injected rats (In); (b) renal-denervated i.c.v. 0.15 M NaCl (Co(Dx), n = 5), and insulin-injected rats (In(Dx), n = 5); and (c) subcutaneously insulin-injected rats (SC, n = 5). We showed that centrally administered insulin produced dose-related increased urinary output of sodium [Co: 855 +/- 85 Delta% min, 0.42 ng.microl(-1) In: 1189 +/- 308 Delta% min, 4.2 ng.microl(-1) In: 1461 +/- 594 Delta% min (p = 0.048), and 42.0 ng.microl(-1) In: 2055 +/- 411 Delta% min (p = 0.0001)], and dose-independently increased potassium excretion [Co: 460 +/- 28 Delta% min, 0.42 ng.microl(-1) In: 649 +/- 100 Delta% min (p = 0.016), 4.2 ng.microl(-1) In: 671 +/- 175 Delta% min (p = 0.003), and 42.0 ng.microl(-1) In: 669 +/- 70 Delta% min (p = 0.002)] compared to control. The urinary sodium excretion response to i.c.v. 42 ng.microl(-1) insulin injections were abolished by bilateral renal denervation. In addition, we showed that insulin-induced natriuresis occurred by increasing postproximal tubule sodium rejection (FEPP(Na)), and changed glomerular filtration rate (C(Cr)) at 42.0 ng.microl(-1) (p = 0.023) i.c.v. insulin microinjection but not at smaller insulin dose. The current data suggests that a blunted efferent insulin-sensitive nerve activity from periventricular region may contribute to the inability of renal tubules to handle the hydroelectrolyte balance.


Assuntos
Encéfalo/metabolismo , Ventrículos Cerebrais/metabolismo , Vias Eferentes/metabolismo , Insulina/metabolismo , Rim/inervação , Equilíbrio Hidroeletrolítico/fisiologia , Animais , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Ventrículos Cerebrais/citologia , Ventrículos Cerebrais/efeitos dos fármacos , Complicações do Diabetes , Diabetes Mellitus/metabolismo , Diabetes Mellitus/fisiopatologia , Relação Dose-Resposta a Droga , Vias Eferentes/citologia , Vias Eferentes/efeitos dos fármacos , Taxa de Filtração Glomerular/efeitos dos fármacos , Taxa de Filtração Glomerular/fisiologia , Hipertensão/etiologia , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Injeções Intraventriculares , Insulina/farmacologia , Rim/fisiopatologia , Capacidade de Concentração Renal/efeitos dos fármacos , Capacidade de Concentração Renal/fisiologia , Túbulos Renais/fisiologia , Masculino , Ratos , Ratos Wistar , Cloreto de Sódio/farmacologia , Equilíbrio Hidroeletrolítico/efeitos dos fármacos
6.
J Chemother ; 26(3): 169-72, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24091354

RESUMO

INTRODUCTION: Thrombotic microangiopathy (TMA) has been reported as a complication of chemotherapy. Many antineoplastic agents have been linked to TMA, gemcitabine being one of the most frequently cited as related to this syndrome. METHODS: A retrospective search for chemotherapy-induced TMA cases among gemcitabine users in a single oncology centre from January 2009 to September 2012 was performed. RESULTS: Three cases of gemcitabine-induced TMA were reported, from a total of 264 patients (incidence: 1·13%) who received the drug. From the three cases reported, two (66%) patients died as a consequence of the syndrome. DISCUSSION: These findings are compatible with previous analyses, which report an incidence of gemcitabine-associated TMA ranging from 0·008 to 2·2% and mortality rates from 15 to 90%. Unlike previously reported, however, cumulative dose was not predictive of risk. CONCLUSION: Gemcitabine-induced TMA is an underdiagnosed condition characterized by high mortality rates. Attention should be called for a higher level of awareness to provide early diagnosis and proper treatment.


Assuntos
Antimetabólitos Antineoplásicos/efeitos adversos , Desoxicitidina/análogos & derivados , Microangiopatias Trombóticas/induzido quimicamente , Adulto , Desoxicitidina/efeitos adversos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Estudos Retrospectivos , Microangiopatias Trombóticas/epidemiologia , Gencitabina
7.
Obesity (Silver Spring) ; 21(12): 2545-56, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23512570

RESUMO

OBJECTIVE: It has become clear that exercise may be a useful therapy in the insulin resistance treatment, as it has anti-inflammatory effects and improves insulin sensitivity. However, it remains uncertain whether exercise affects the adipocytes or infiltrated macrophages. Thus, the aim was to investigate the effects of acute exercise on the inflammatory status and insulin signaling of the white adipose tissue (WAT) fractions (stromal-vascular fraction [SVF] and adipocytes). DESIGN AND METHODS: The effect of acute swimming exercise was investigated on insulin sensitivity, insulin signaling, inflammatory pathways in the WAT fractions of high-fat fed Wistar rats. Additionally, macrophage infiltration and polarization were analyzed in the WAT. RESULTS: Acute exercise can improve insulin signaling in WAT fractions, along with a phenotypic switch from M1- to M2-macrophages in obese rats, as indicated by a marked increase in macrophage galactose-type C-type lectin 1-positive cells in WAT was observed. Additionally, exercise promoted a reduction in circulating levels of lipopolysaccharide, and toll-like receptor 4 activity along with TNF-alpha, IL-1-beta and MCP-1 mRNA levels in WAT fractions. CONCLUSIONS: These data suggest that acute exercise improves insulin signaling in the WAT, at least in part by inducing macrophage polarization toward the M2-state.


Assuntos
Tecido Adiposo Branco/citologia , Dieta Hiperlipídica/efeitos adversos , Macrófagos/metabolismo , Obesidade/metabolismo , Condicionamento Físico Animal , Adipócitos/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Quimiocina CCL2/sangue , Insulina/sangue , Resistência à Insulina , Interleucina-1/sangue , Interleucina-10/sangue , Lipopolissacarídeos/sangue , Masculino , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/sangue
8.
Diabetes ; 62(1): 137-48, 2013 01.
Artigo em Inglês | MEDLINE | ID: mdl-22966070

RESUMO

Mutation of tub gene in mice induces obesity, suggesting that tub could be an important regulator of energy balance. In the current study, we investigated whether insulin, leptin, and obesity can modulate Tub in vivo in hypothalamic nuclei, and we investigated possible consequences on energy balance, neuropeptide expression, and hepatic glucose metabolism. Food intake, metabolic characteristics, signaling proteins, and neuropeptide expression were measured in response to fasting and refeeding, intracerebroventricular insulin and leptin, and Tub antisense oligonucleotide (ASO). Tub tyrosine phosphorylation (Tub-p-tyr) is modulated by nutritional status. Tub is a substrate of insulin receptor tyrosine kinase (IRTK) and leptin receptor (LEPR)-Janus kinase 2 (JAK2) in hypothalamic nuclei. After leptin or insulin stimulation, Tub translocates to the nucleus. Inhibition of Tub expression in hypothalamus by ASO increased food intake, fasting blood glucose, and hepatic glucose output, decreased O(2) consumption, and blunted the effect of insulin or leptin on proopiomelanocortin, thyroid-releasing hormone, melanin-concentrating hormone, and orexin expression. In hypothalamus of mice administered a high-fat diet, there is a reduction in leptin and insulin-induced Tub-p-tyr and nuclear translocation, which is reversed by reducing protein tyrosine phosphatase 1B expression. These results indicate that Tub has a key role in the control of insulin and leptin effects on food intake, and the modulation of Tub may contribute to insulin and leptin resistance in DIO mice.


Assuntos
Hipotálamo/fisiologia , Insulina/farmacologia , Leptina/farmacologia , Proteínas/fisiologia , Transdução de Sinais/fisiologia , Transporte Ativo do Núcleo Celular , Proteínas Adaptadoras de Transdução de Sinal , Animais , Jejum , Janus Quinase 2/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oligonucleotídeos Antissenso/farmacologia , Fosfolipase C beta/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/fisiologia , Proteínas/antagonistas & inibidores
12.
Rev. bras. med. esporte ; 15(3): 179-184, maio-jun. 2009. ilus, graf
Artigo em Português | LILACS | ID: lil-517532

RESUMO

INTRODUÇÃO: A deficiência na captação de glicose em tecidos periféricos e o aumento da gliconeogênese hepática são fenômenos fisiopatológicos observados em pacientes diabéticos do tipo 2. O exercício físico é considerado um importante aliado para a melhora do perfil glicêmico em pacientes diabéticos; entretanto, os mecanismos envolvidos nesse processo não estão completamente elucidados. OBJETIVO: Avaliar o papel da proteína AMPK no controle glicêmico em camundongos diabéticos após o exercício físico. MÉTODOS: Durante o jejum, o teste de tolerância à insulina (ITT) e a técnica de Western blot foram combinados para avaliar a homeostase da glicose em camundongos diabéticos (ob/ob e db/db) submetidos a uma única sessão de natação. RESULTADOS: A hiperglicemia de jejum, a severa resistência à insulina e a deficiência na sinalização da via AMPK/ACC no músculo e no fígado observadas nos camundongos diabéticos foram revertidas após a sessão de exercício. A restauração da via AMPK/ACC reduziu a expressão da enzima gliconeogênica PEPCK no fígado e aumentou a translocação do GLUT4 no músculo esquelético. Esses dados apontam que a ativação da via AMPK/ACC induzida pelo exercício físico é importante para a redução da glicemia de jejum em modelos experimentais de diabetes tipo 2. Esses dados abrem novas frentes para o entendimento de como a atividade física controla da homeostase da glicose em pacientes diabéticos.


INTRODUCTION: The deficiency in glucose uptake in peripheral tissues and increased hepatic gluconeogenesis are physiopathological phenomena observed in type 2 diabetes patients. Physical exercise plays an important role in the improvement of glycemic profile in diabetic patients; however, the mechanisms involved in these processes have not been fully elucidated. OBJECTIVE: to assess the role of AMPK protein in the glycemic control of diabetic mice after exercise. METHODS: During fasting condition, the insulin tolerance test (ITT) and Western blot technique, were combined to assess the glucose homeostasis in diabetic mice (ob/ob and db/db) after a single swimming session. RESULTS: Fasting hyperglycemia, severe insulin resistance and deficiency in the AMPK/ACC signaling in muscle and liver observed in the diabetic mice were reversed after the exercise session. The restoration of AMPK/ACC signaling reduced the expression of the gluconeogenic enzyme, PEPCK in the liver, and increased the translocation of GLUT4 in the skeletal muscle. These data indicate that the activation of AMPK/ACC pathway induced by physical exercise is important to reduce fasting glucose levels in experimental models of type 2 diabetes. These data open new insights for determination of physical activity control on the glucose homeostasis in diabetic patients.


Assuntos
Animais , Camundongos , Fígado/citologia , Hiperglicemia , Músculos/citologia , Natação , Transdução de Sinais
13.
Arq. bras. endocrinol. metab ; 51(2): 195-203, mar. 2007. ilus
Artigo em Português | LILACS | ID: lil-449573

RESUMO

Insulina (Ins) e Angiotensina II (AII) são fundamentais no controle de dois sistemas vitais e inter-relacionados: o metabólico e o cardiocirculatório, respectivamente. A disfunção de qualquer um desses hormônios pode levar ao desenvolvimento de duas doenças de alta prevalência, muitas vezes concomitantes e, talvez, com fisiopatologia integrada - diabetes mellitus (DM) e hipertensão arterial (HA). Vários estudos mostram que os sistemas de sinalização intracelular de Ins e AII estão conectados e influenciam um ao outro. Esta comunicação molecular ocorre em diferentes etapas da sinalização celular e é importante para vários fenômenos fisiológicos, desde o desenvolvimento de hipertrofia cardíaca e aquisição de energia pelo coração, até a ação de drogas anti-hipertensivas. No nível extracelular, a enzima de conversão de angiotensina regula a síntese de AII e o acúmulo de bradicinina, e ambos desempenham papel regulador sobre a sinalização de Ins. No nível intracelular, a interação dos sinais de Ins e AII ocorre em dois momentos distintos. Inicialmente, em etapas mais precoces da sinalização celular, a AII, atuando através da cascata JAK-2/IRS-1/PI3-quinase, JNK e ERK, provoca a fosforilação em serina e a conseqüente inibição de elementos-chave da via de sinalização da Ins. Finalmente, a AII induz a expressão da proteína regulatória SOCS-3, que impõe um controle mais tardio sobre o sinal de Ins. Esta revisão discute os avanços mais recentes neste campo e a importância dessa interação molecular na fisiopatologia e na associação clínica de DM e HA.


Insulin (Ins) and angiotensin II (AII) play pivotal roles in the control of two vital and closely related systems: the metabolic and the circulatory, respectively. A failure in the proper action of each of these hormones results, to a variable degree, in the development of two highly prevalent and commonly overlapping diseases - diabetes mellitus (DM) and hypertension (AH). In recent years, a series of studies has revealed a tight connection between the signal transduction pathways that mediate Ins and AII actions in target tissues. This molecular cross-talk occurs at multiple levels and plays an important role in phenomena that range from the action of anti-hypertensive drugs to cardiac hypertrophy and energy acquisition by the heart. At the extracellular level, the angiotensin-converting enzyme controls AII synthesis but also interferes with Ins signaling through the proper regulation of AII and the accumulation of bradykinin. At an early intracellular level, AII, acting through JAK-2/IRS-1/PI3-kinase, JNK and ERK, may induce the serine phosphorylation and inhibition of key elements of the Ins-signaling pathway. Finally, by inducing the expression of the regulatory protein SOCS-3, AII may impose a late control on the Ins signal. This review will focus on the main advances obtained in this field and will discuss the implications of this molecular cross-talk in the common clinical association between DM and AH.


Assuntos
Animais , Humanos , Angiotensina II/fisiologia , Diabetes Mellitus/fisiopatologia , Hipertensão/fisiopatologia , Resistência à Insulina/fisiologia , Insulina/fisiologia , Transdução de Sinais/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas Supressoras da Sinalização de Citocina/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA