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1.
Mediators Inflamm ; 2023: 4035516, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37662481

RESUMO

Sepsis is a life-threatening clinical condition caused by infection and transposition of pathogens and pathogen-associated molecular patterns (PAMPs) into the host bloodstream. During sepsis, activation of toll-like receptors (TLRs) on immune cells triggers the release of pro-inflammatory cytokines and overstimulates the production of vasodilatory mediators such as nitric oxide (NO). These vascular changes lead to widespread inflammation, tissue damage, multiple organ failure, and often death. New therapeutic options are urgently needed. To this end, thiostrepton (TST) has emerged as a candidate for sepsis treatment due to its action as an antibiotic and anti-inflammatory molecule (TLR7-9 inhibitor). Reports in the literature suggest that TLR9 inhibition substantially suppresses the excessive host inflammatory response and attenuates sepsis-induced mortality in the cecal ligation and puncture (CLP) murine model of sepsis. However, to the best of our knowledge, TST has never been directly tested as a therapeutic option for the management of sepsis, possibly due to its low water solubility and drug delivery issues. These facts prompted us to test the central hypothesis that TST encapsulated in phospholipid sterically stabilized micelles (TST-SSM) could be developed into a novel treatment for sepsis. Thus, using our published method of encapsulating the hydrophobic antibiotic TST-SSM, we evaluated the in vivo efficacy of TST-SSM nanomedicine in the murine model of polymicrobial sepsis. We found that TST-SSM increased the median survival of CLP-induced septic mice from 31 to 44 hr by reducing the bacterial burden in the blood and peritoneal lavage. Moreover, plasma levels of pro-inflammatory cytokines (interleukin 6 and tumor necrosis factor-alpha) and NO derivatives were also reduced, whereas renal and hepatic function biomarkers creatinine and aspartate transferase were significantly improved. In conclusion, we identified that TST-SSM nanomedicine has significant potential as a therapeutic agent for sepsis management, primarily due to its anti-inflammatory and antibiotic properties.


Assuntos
Sepse , Tioestreptona , Animais , Camundongos , Receptor Toll-Like 9 , Modelos Animais de Doenças , Nanomedicina , Sepse/tratamento farmacológico , Inflamação/tratamento farmacológico , Antibacterianos , Citocinas
2.
J Bone Metab ; 21(1): 69-75, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24707469

RESUMO

BACKGROUND: Sclerostin inhibits osteoblast functions, differentiations, and survival rates. As an endogenous inhibitor of the Wnt/ß-catenin pathway, the sclerostin should be related to decreased bone masses, although several studies indicate opposite results. In addition, it may be related to insulin resistances and carbohydrate metabolisms, a relation shared with other markers of bone metabolisms, such as osteocalcin. Hepatitis C virus (HCV) infected patients may present osteoporosis, and frequently show liver steatosis, which is a consequence of insulin resistance. The behaviour of sclerostin in these patients is yet unknown. The aim of this work is to analyse the relationships between serum sclerostin and osteocalcin levels and bone mineral density (BMD), liver functions, the intensity of liver steatosis and biochemical markers of bone homeostasis and insulin resistance in HCV-infected patients. METHODS: Forty HCV patients with 20 years of age and gender-matching controls were included in this study and underwent bone densitometry. Serum sclerostin, osteocalcin, collagen telopeptide, adiponectin, leptin, insulin, resistin, tumor necrosis factor (TNF)-α, and interleukin (IL)-6 were determined. Liver fat was histomorphometrically assessed. RESULTS: Sclerostin levels were slightly higher in patients than in controls, and were directly related to BMD at different parts of the skeleton, also to the serum telopeptide, and to the liver steatosis and TNF-α. On the contrary, osteocalcin showed a significant direct relationship with serum adiponectin, and an inverse one with IL-6. CONCLUSIONS: Serum sclerostin levels were within the normal range in HCV patients, and correlated directly with BMD and serum telopeptide. In addition, the relationships of sclerostin and osteocalcin with variables associated with insulin resistance suggested the role of bones for intermediary metabolisms.

3.
Alcohol Alcohol ; 47(4): 390-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22510812

RESUMO

UNLABELLED: In alcoholics, the activation of Kupffer cells by gram negative bacteriae leads to an inflammatory response and cytokine secretion, which in turn activate T-lymphocytes. Possibly, Th-1 lymphocytes are activated first, followed by a Th-2 response. Th-2 cytokines, especially interleukin (IL)-13 (scarcely studied in alcoholics), may be involved in the progression to chronic stages. AIMS: The aim of the study was to analyze the relationship of Th-1 and Th-2 cytokines with liver function, alcohol consumption, nutritional status and survival. METHODS: Serum Th-1 [interferon-γ (IFN-γ)] and Th-2 cytokines (IL-4, IL-13), IL-10, IL-6 and tumor necrosis factor (TNF-α), were determined for 18 controls and 47 stable alcoholics with variable liver function impairment, who were followed-up during a median time of 90 months, a period during which 14 patients died. RESULTS: IL-4 was lower among patients; no differences were observed regarding IL-6, but the remaining ILs were higher among alcoholics. IL-10 and IL-13 were even higher in cirrhotics (Z = 2.88, P = 0.004, and Z = 2.09, P = 0.037, respectively). A significant, direct, correlation was observed between IL-13 and IL-10 (ρ = 0.49, P = 0.001), and non-significant, inverse ones were observed between IFN-γ and IL-13 (ρ = -0.23), IL-4 (ρ = -0.14) and IL-10 (ρ = -0.09). IL-13 and IL-10 were inversely related with liver function and, directly with immunoglobulin A levels, but not with survival. CONCLUSION: Serum IFN-γ values were increased in alcoholics, who also showed raised IL-13 and IL-10, but lower IL-4 levels. Given the immunomodulatory roles of IL-10 and IL-13, this increase may be interpreted as a compensatory rise of anti-inflammatory cytokines. We failed to find any relation with mortality.


Assuntos
Alcoolismo/sangue , Interferon gama/sangue , Interleucinas/sangue , Cirrose Hepática Alcoólica/sangue , Fígado/fisiopatologia , Fator de Necrose Tumoral alfa/sangue , Adulto , Alcoolismo/complicações , Alcoolismo/mortalidade , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Cirrose Hepática Alcoólica/fisiopatologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Estatísticas não Paramétricas
4.
Alcohol Alcohol ; 41(6): 593-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17028306

RESUMO

AIMS: Increased exposure of Kupffer cells to intestinal-borne Gram-negative bacteria enhances the metabolism and leads to cytokine production by these cells. Activation of Kupffer cells increases free radical release, which may, in turn, enhance cytokine secretion, creating a positive feedback loop, which contributes to liver inflammation. Cytokines act on T cells, inducing their proliferation and secretion of additional interleukins. Lipid peroxidation products (malondialdehyde; MDA) form adducts with proteins and acetaldehyde, triggering a T cell immune response. Controversy exists about the predominance of either Th-1 or Th-2 cellular responses. We performed the present study in order to analyse the cytokine pattern in patients with acute alcoholic hepatitis, its relation to MDA and the relation between all these parameters and liver function and prognosis. SUBJECTS AND METHODS: The study included 53 male alcoholics, 47 followed up for a median time of 32 months, during which 17 of them died. We measured serum MDA, tumour necrosis factor-alpha, interferon gamma (IFNG) and interleukins (IL) 4, 6, 8, and 10. RESULTS: MDA levels were raised in cirrhotics and non-cirrhotics with alcoholic hepatitis, maintaining a relationship with bilirubin and Maddrey index, and with mortality in the univariate analysis. Both IFNG and IL-4 were raised in our patients compared with controls, as well as IL-8, and IL-6, but IL-10 were below the detection limit in the majority of cases, especially in cirrhotics. Using a Cox regression model, Maddrey index displaced MDA in the survival analysis. CONCLUSIONS: Our data lend support to the hypothesis that activation of both Th-1 and Th-2 cell subsets take place. MDA levels are raised in alcoholics with alcoholic hepatitis and are closely related to liver function derangement and to survival, although this is displaced by Maddrey index using Cox regression model.


Assuntos
Citocinas/sangue , Hepatite Alcoólica/fisiopatologia , Peroxidação de Lipídeos/fisiologia , Doença Aguda , Adulto , Idoso , Bilirrubina/metabolismo , Citocinas/biossíntese , Radicais Livres/metabolismo , Bactérias Gram-Negativas/isolamento & purificação , Hepatite Alcoólica/sangue , Humanos , Células de Kupffer/metabolismo , Células de Kupffer/microbiologia , Fígado/metabolismo , Fígado/fisiopatologia , Cirrose Hepática/sangue , Cirrose Hepática/fisiopatologia , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Fatores de Tempo
5.
Alcohol Alcohol ; 37(2): 132-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11912068

RESUMO

This study was performed in order to determine the relative and combined effects of ethanol, a low protein diet and steroid treatment on bone, muscle, liver, and urinary and faecal excretion of zinc, copper and iron in 64 rats divided into eight groups treated following the Lieber-DeCarli liquid diet technique, with and without dexamethasone, 1 mg/l. Steroids showed a lack of effect on liver zinc, but enhanced ethanol- and low protein-mediated liver iron overload when both factors were combined. Steroids also increased muscle copper, iron and zinc, and bone copper, especially in the low protein, ethanol-fed rats.


Assuntos
Cobre/urina , Etanol/farmacocinética , Fezes/química , Ferro/urina , Deficiência de Proteína/metabolismo , Esteroides/farmacocinética , Zinco/urina , Animais , Depressores do Sistema Nervoso Central/farmacocinética , Cobre/metabolismo , Combinação de Medicamentos , Ferro/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual/fisiologia , Zinco/metabolismo
6.
Rev Esp Med Nucl ; 19(6): 416-22, 2000 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-11060271

RESUMO

UNLABELLED: The presence of affected locoregional lymph nodes should be considered as one of the most important prognostic factors of breast cancer. At present, the clinician is conditioned by an absolute lack of an efficient methodology to evaluate the possible invasion of the axillary lymph nodes, which if negative, would make it possible to avoid surgical excision. In this study, we will evaluate the use of the 99mTc-MIBI scintigraphy in the pre-surgical diagnosis of axillary lymph node invasion and will analyze the relationship between the 99mTc-MIBI uptake and the number of lymph nodes affected. MATERIAL AND METHODS: 84 patients diagnosed of breast cancer were analyzed in this study. All of them underwent a 99mTc-MIBI scintigraphy, and the tumor/background ratio was determined semiquantitively for each image. The axillary lymph node invasion was determined following surgery. RESULTS: The sensitivity of the breast scintigraphy with 99mTc-MIBI for detection of lymph node invasion is 36% and the specificity is 100%. The positive predictive value is 100% and the negative one 48%. In the current study, we failed to detect correlation between the intensity of 99mTc-MIBI uptake in the primary tumor and the number of affected axillary lymph nodes. CONCLUSION: 99mTc-MIBI breast scintigraphy can provide complementary information for the presurgical diagnosis of breast cancer axillary lymph node invasion. 99mTc-MIBI breast scintigraphy shows high specificity and a high predictive value.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Sestamibi , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Neoplasias da Mama/patologia , Feminino , Humanos , Linfonodos/patologia , Metástase Linfática/diagnóstico por imagem , Pessoa de Meia-Idade , Invasividade Neoplásica , Cintilografia , Sensibilidade e Especificidade
7.
Rev Esp Med Nucl ; 19(4): 263-9, 2000 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-11062096

RESUMO

UNLABELLED: (99m)Tc-MIBI has been proposed as an imaging diagnostic method in a large variety of human malignant tumors. At present, the mechanism by which (99m)Tc-MIBI is uptaken and concentrated by the malignant cells is not totally known. Some mammary neoplasms do not show any uptake of (99m)Tc-MIBI. This study aims to determine if there is any correlation between the uptake of (99m)Tc-MIBI by the tumor and the different histopathological parameters involved in tumoral aggressiveness. To do so, we have studied 100 patients with breast cancer. All of them underwent a breast scintimammography with (99m)Tc-MIBI with semiquantitative analysis by means of a tumor-to-background ratio calculated in every projection. After surgery, an experienced pathologist determined tumor size, axillary lymph node metastases, histological grade (Scarff Bloom Richardson) (SCBR), nuclear grade, mitotic index, presence of cellular atypia and estrogen and progesterone receptor expression. RESULTS: A statistically significant correlation (p < 0.005) has been found between tumor-to-background (T/B) ratios of (99m)Tc-MIBI uptake and tumor SCBR histological grade. A correlation between (99m)Tc-MIBI uptake and the mitotic index, cellular atypia and nuclear grade has also been found. No correlation was found in our study with tumor size, hormone receptor expression or axillary lymph node metastases. CONCLUSIONS: (99m)Tc-MIBI uptake in breast cancer is correlated with the tumoral differentiation grade: the smaller the tumoral cellular differentiation (greater aggressiveness), the greater the uptake. On the other hand, no correlation was found between the uptake of (99m)Tc-MIBI and the classical pathological parameters that define tumoral aggressiveness, such as size and axillary lymph node metastasis.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Cuidados Pré-Operatórios , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Sestamibi , Feminino , Humanos , Cintilografia
8.
Rev Esp Med Nucl ; 19(5): 344-9, 2000 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-11062110

RESUMO

UNLABELLED: Breast scintimammography with 99mTc-MIBI has proven to be a useful complement to mammography in the diagnosis of breast cancer in the female population. Although the mammography, along with a physical examination, is the backbone of breast cancer diagnosis, there are groups of patients in whom the mammography has an even lower specificity. OBJECTIVE: Our study has aimed to assess the usefulness of breast 99mTc-MIBI scintimammography in those situations in which the mammography was indeterminate, such as, in dense breasts, young females or breasts with architectural distortion after surgery or radiation therapy. MATERIALS AND METHODS: We studied 109 females with mammographically dense breasts, 8 young females under 30 and 24 patients who had undergone previous surgery or radiation therapy. All cases were studied to rule out breast cancer. Final diagnosis was established with excisional biopsy. RESULTS: In dense breasts MIBI scintimammography sensitivity was 88% and the mammography one 81%. MIBI scintimammography specificity was 90% and the mammography 28%. In young females MIBI scintimammography sensitivity was 100% and the mammography 50%, MIBI scintimammography specificity 100% and the mammography 20%. In previous surgery, MIBI scintimammography sensitivity was 80% and the mammography 80%, MIBI scintimammography specificity 100% and the mammography 42%. CONCLUSION: Breast scintimammography with 99mTc-MIBI is an excellent diagnostic technique with high specificity. Undoubtedly it is complementary to mammography in those cases where mammography has major limitations such as dense breasts, young females and breasts with severe scarring after surgery or radiation therapy.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Mamografia , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Sestamibi , Adulto , Fatores Etários , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Feminino , Humanos , Recidiva Local de Neoplasia/diagnóstico por imagem , Cintilografia , Sensibilidade e Especificidade
9.
J Biol Chem ; 259(5): 2896-9, 1984 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-6321484

RESUMO

The receptors and actions of gonadotropin-releasing hormone (GnRH) were analyzed in cultured testicular cells from 20.5-day fetal rats, in which treatment with luteinizing hormone (LH) maintained Leydig cell steroidogenesis and gonadotropic responses for up to 2 weeks. Testicular GnRH receptors were present on the 5th postnatal day, but were not demonstrable in fetal testes or 2-day cultures thereof. However, GnRH receptors were readily detectable in 4-day cultured fetal testes and were increased by exposure to GnRH agonists. In LH-treated cultures, GnRH sites were reduced by about 50% and did not increase during incubation with GnRH agonists. In such cultures, GnRH agonists inhibited LH-dependent steroid production and abolished the acute testosterone response to human chorionic gonadotropin. The half-maximal inhibitory concentration of [D-Ala6]des-Gly10-GnRH-N-ethylamide (3 X 10(-10)M) was commensurate with its binding affinity for testis receptors (Kd = 1.4 X 10(-10)M). In contrast, GnRH agonists had no inhibitory effects in 2-day cultures prior to the detection of GnRH receptors. The expression of functional GnRH receptors during culture in the absence of gonadotropin and their suppression in LH-treated cultures suggest that pituitary gonadotropins exert a tonic inhibitory effect upon testicular GnRH receptors. The demonstrated inhibitory actions of GnRH on steroidogenesis, with the expression of GnRH receptors in cultured fetal testes and 5-day postnatal testes, indicate that GnRH agonists could influence the actions of gonadotropins upon Leydig cell function in the neonatal testis.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Células Intersticiais do Testículo/metabolismo , Hormônio Luteinizante/farmacologia , Receptores de Superfície Celular/metabolismo , Animais , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Feminino , Feto , Hormônio Liberador de Gonadotropina/farmacologia , Cinética , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Gravidez , Ratos , Receptores de Superfície Celular/isolamento & purificação , Receptores LHRH , Testículo/embriologia , Testosterona/metabolismo
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