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1.
Ann Vasc Surg ; 78: 378.e9-378.e15, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34455049

RESUMO

To describe a new inner-branched device used to treat two cases of chronic post-dissection aortic thoraco-abdominal aneurysms (PD-TAAAs) after ascending aortic surgery. A 67-year-old male who had undergone an ascending aorta and arch surgical replacement and a 70-year-old male with a previous Bentall procedure for acute type A aortic dissection were admitted at our department with a PD-TAAA diagnosis. Both patients were defined unfit for open surgery by a multidisciplinary team and a totally percutaneous endovascular repair was planned. A prophylactic cerebro-spinal fluid drainage was applied and at least one hypogastric artery was targeted for salvage in order to reduce the risk of spinal cord ischemia. A new inner branch device by Jotec® (GmbH/ Criolife; Hechingen, Germany/Kennesaw, Georgia) was implanted. A TEVAR and a standard EVAR completed the procedures and a double barrel technique was performed in order to achieve the preservation of the selected hypogastric artery. In both patients the complete technical success was achieved. The postoperative period was uneventful and the patients were discharged on the 6th and 7th postoperative day, respectively. The triple-phase angio-CT performed at 6 months showed the complete false lumen exclusion and the patency of the endografts and of the target visceral vessels. The total endovascular treatment of PD-TAAAs is a fascinating technique with encouraging results in experienced centers. Inner branched devices may expand the field of application of this new technology. More data are required to evaluate mid- and long-term results.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Stents , Idoso , Dissecção Aórtica/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico por imagem , Humanos , Masculino , Desenho de Prótese , Resultado do Tratamento
2.
Eur Rev Med Pharmacol Sci ; 25(13): 4456-4458, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34286507

RESUMO

Utero-Placental Apoplexy, or Couvelaire Uterus, is a third-trimester major obstetrical complication, occurring especially during labor. It consists of placental abruption followed by an acute intradecidual hemorrhage produced by the rupture of the uterus-placental spiral arterioles leading to a retroplacental hematoma. This hemorrhage infiltrates the uterine wall up to intra- and retro-peritoneal areas. We provide a case report, on which no previous literature is available, of a utero-placental apoplexy during induction of therapeutic abortion.


Assuntos
Aborto Terapêutico/efeitos adversos , Descolamento Prematuro da Placenta/etiologia , Hemorragia Uterina/etiologia , Descolamento Prematuro da Placenta/cirurgia , Adulto , Feminino , Humanos , Histerectomia , Gravidez , Salpingo-Ooforectomia , Hemorragia Uterina/cirurgia
3.
Nat Commun ; 10(1): 1945, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31019194

RESUMO

The original version of this Article contained an error in Fig. 4. In the left histogram of the right panel of Fig. 4d, several data points were inadvertently deleted from the histogram during the production process. This error has been corrected in both the PDF and HTML versions of the Article. The original, incorrect version of Fig. 4 is presented in the accompanying Publisher Correction.

4.
Nat Commun ; 10(1): 766, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30770823

RESUMO

Primary triple negative breast cancers (TNBC) are prone to dissemination but sub-clonal relationships between tumors and resulting metastases are poorly understood. Here we use cellular barcoding of two treatment-naïve TNBC patient-derived xenografts (PDXs) to track the spatio-temporal fate of thousands of barcoded clones in primary tumors, and their metastases. Tumor resection had a major impact on reducing clonal diversity in secondary sites, indicating that most disseminated tumor cells lacked the capacity to 'seed', hence originated from 'shedders' that did not persist. The few clones that continued to grow after resection i.e. 'seeders', did not correlate in frequency with their parental clones in primary tumors. Cisplatin treatment of one BRCA1-mutated PDX model to non-palpable levels had a surprisingly minor impact on clonal diversity in the relapsed tumor yet purged 50% of distal clones. Therefore, clonal features of shedding, seeding and drug resistance are important factors to consider for the design of therapeutic strategies.


Assuntos
Células Clonais , Neoplasias de Mama Triplo Negativas/genética , Animais , Proteína BRCA1/genética , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Mutação/genética , Recidiva Local de Neoplasia/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Eur J Gynaecol Oncol ; 36(1): 84-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25872341

RESUMO

The malignant transformation of a uterine leiomyoma is still debated and, if it occurs, it is very rare. The case of a patient affected by one small leiomyoma is described. Diagnosis was made postoperatively on histopathological examination. The case reported here is meant to underline the need to keep all uterine myomas in check since the transition into leiomyosarcomas (LMSs) may occur with an evolution over a time period which has not been established so far. Specific receptors for luteinizing hormone/human chorionic gonadotropin (LH/hCG) have also been identified in the myometrium of several animal species, including humans. Conventional LMSs express estrogen receptors (ER), progesterone receptors (PR), and androgen receptors (AR) in 30-40% of cases. In comparison with other more common uterine malignancies, uterine LMSs bear some resemblance to type 2 endometrial carcinomas and high-grade serous carcinomas of ovary/fallopian tube origin, based on their genetic instability, frequent p53 abnormalities, aggressive behavior, and resistance to chemotherapy. It could be useful to understand with further researches if hormonal stimulation could be a contributing factor of uterine leiomyoma transformation into LMS. Until today the oncogenic mechanisms underlying the development of uterine LMSs remain elusive.


Assuntos
Transformação Celular Neoplásica/patologia , Leiomioma/patologia , Leiomiossarcoma/patologia , Neoplasias Uterinas/patologia , Adulto , Feminino , Humanos , Leiomioma/cirurgia , Leiomiossarcoma/cirurgia , Neoplasias Uterinas/cirurgia
6.
Eur J Gynaecol Oncol ; 35(1): 16-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24654455

RESUMO

OBJECTIVE: To analyse the correlation between the colposcopic parameters of Grade 1 and Grade 2 abnormal transformation zone (ANTZ G1-ANTZ G2) and histological examination of the cone. MATERIALS AND METHODS: A retrospective analysis of medical records of 600 women who underwent colposcopy and conisation (large loop excision of the transformation zone - LLETZ) between January 1, 2009 and July 31, 2012. The correlation between colposcopic and histological parameters was analysed using the Spearman nonparametric test. RESULTS: In ANTZG1 there was no correlation (r = - 0.03; p = 0.55); in ANTZG2 however, a low degree of correlation (r = 0.21; p = 0.03) was found. Sensitivity, specificity, and positive and negative predictive values of an ANTZ G2 colposcopic picture were 33.45% (confidence interval [CI] 95% 28.0% to 39.2%), 95.48% (CI 95% 92.5% to 97.5%), 87.4% (CI 95% 79.7% to 92.9%), and 60.5% (CI 95% 56% to 64.9%), respectively. CONCLUSIONS: The decisive factor in the diagnosis of the cervical oncologic pathologies is the histological examination of the cone, and not the colposcopy which should be seen as a "guiding" investigation in predicting conisation and application of the most appropriate treatment.


Assuntos
Colposcopia/métodos , Conização/métodos , Neoplasias do Colo do Útero/patologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/classificação , Neoplasias do Colo do Útero/diagnóstico
7.
Eur J Gynaecol Oncol ; 35(1): 87-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24654471

RESUMO

Placental site trophoblastic tumor (PSTT) is the least common form of gestational trophoblastic disease (GTD), and is biologically different from other forms of GTD. There is a wide clinical spectrum of presentation and behavior ranging from a benign condition to an aggressive disease with a fatal outcome. The authors document a case of PSTT on an endometrial polyp. A 51-year-old woman had abnormal vaginal bleeding for the duration of two months. Her past history included a vaginal delivery in 1998. Her physical examination was normal. Tumor markers were at normal levels. Serum beta- human chorionic gonadotropin (hCG) level was 19 mIU/ml and human placental lactogen (hPL) level was in the normal range. The patient underwent an operative hysteroscopy. On examination the uterine cavity appeared to be occupied by a pedunculated polypoid neoformation measuring about 2.5 cm in diameter which was removed and later determined to be a PSTT. There were occasional mitotic figures (0-1/10 high power field). The patient underwent hysterectomy and bilateral salpingo-oophorectomy. The patient has no evidence of disease six months after surgery. The authors conclude that a high mitotic count and atypical undifferentiated pathological features are significant poor prognostic factors for survival in PSTT. Hysterectomy represents the gold standard of treatment in all cases of disease confined to the uterus.


Assuntos
Pólipos/diagnóstico , Tumor Trofoblástico de Localização Placentária/diagnóstico , Doenças Uterinas/diagnóstico , Feminino , Humanos , Histerectomia , Pessoa de Meia-Idade , Pólipos/patologia , Pólipos/cirurgia , Gravidez , Tomografia Computadorizada por Raios X , Tumor Trofoblástico de Localização Placentária/patologia , Tumor Trofoblástico de Localização Placentária/cirurgia , Doenças Uterinas/patologia , Doenças Uterinas/cirurgia
8.
Clin Exp Obstet Gynecol ; 40(4): 596-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24597266

RESUMO

Placenta accreta refers to any abnormally invasive placental implantation. Diagnosis is suspected postpartum with failed delivery of a retained placenta. Massive obstetrical hemorrhage is a known complication, often requiring peripartum hysterectomy. The authors report a case of placenta accreta in a primiparous patient with multinodular leiofibromyomatosis of the uterus following failed manual removals of a retained placenta. They describe a conservative management in a stable patient desiring future fertility with a unilateral prophylactic uterine artery embolization, a multidose regimen of methotrexate, and a subsequent abdominal myomectomy.


Assuntos
Preservação da Fertilidade/métodos , Placenta Acreta/terapia , Embolização Terapêutica , Feminino , Humanos , Histerectomia , Metotrexato/administração & dosagem , Paridade , Gravidez , Artéria Uterina , Miomectomia Uterina
9.
IEEE Trans Pattern Anal Mach Intell ; 34(1): 127-43, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21576734

RESUMO

Pattern matching is widely used in signal processing, computer vision, and image and video processing. Full search equivalent algorithms accelerate the pattern matching process and, in the meantime, yield exactly the same result as the full search. This paper proposes an analysis and comparison of state-of-the-art algorithms for full search equivalent pattern matching. Our intention is that the data sets and tests used in our evaluation will be a benchmark for testing future pattern matching algorithms, and that the analysis concerning state-of-the-art algorithms could inspire new fast algorithms. We also propose extensions of the evaluated algorithms and show that they outperform the original formulations.

10.
Eur J Gynaecol Oncol ; 33(6): 669-71, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23327070

RESUMO

Aggressive angiomyxoma (AA) is a rare mesenchimal tumor usually located in the pelvic and perineal region. Less than 30 cases of aggressive angiomyxoma with vaginal location have been reported in the literature up to this date. The authors report the case of a 50-year-old female patient diagnosed with vaginal AA whose characteristics at its initial stage were macroscopically indistinguishable from those of a polypoid lesion. Therefore this case suggests that this type of tumor should be considered as part of the differential diagnosis of vaginal polypoid lesions.


Assuntos
Mixoma/patologia , Neoplasias Vaginais/patologia , Feminino , Proteína HMGA2/análise , Humanos , Pessoa de Meia-Idade , Mixoma/química , Mixoma/terapia , Estadiamento de Neoplasias , Neoplasias Vaginais/química , Neoplasias Vaginais/terapia
11.
J Bioenerg Biomembr ; 43(4): 387-97, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21732173

RESUMO

In cold exposed rats, it is known that vitamin E induces an increase in the respiration of the whole mitochondrial population isolated from liver. To obtain information on the effects of cold exposure and vitamin E treatment on the dynamics of mitochondrial population, we determined characteristics of rat liver mitochondrial fractions, resolved at 1,000 (M(1)), 3,000 (M(3)), and 10,000 g (M(10)). We found that cold exposure increased the liver content of total mitochondrial proteins irrespective of vitamin E treatment. Conversely, protein distribution among the mitochondrial subpopulations was differentially affected by cold and antioxidant integration. In a cold environment, the M(1) fraction, characterized by the highest O(2) consumption and H(2)O(2) production rates, underwent a remarkable protein content reduction, which was attenuated by vitamin E. These changes were dependent on the opposite effects of the two treatments on mitochondrial oxidative damage and susceptibility to swelling. The proteins of the other fractions, in which the above effects were lower, underwent smaller (M(3)) or no change (M(10)) in the treatment groups. The cold also led to an increase in O(2) consumption of the M(1) fraction which was accentuated by vitamin E treatment. This phenomenon and the vitamin-induced recovery of the M(1) proteins supply an explanation of the previously reported increase in the respiration of the whole mitochondrial population induced by vitamin E in the liver from cold exposed rats.


Assuntos
Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Vitamina E/farmacologia , Animais , Antioxidantes/metabolismo , Temperatura Baixa , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Coração/anatomia & histologia , Peróxido de Hidrogênio/antagonistas & inibidores , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Proteínas Mitocondriais/metabolismo , Modelos Animais , Tamanho do Órgão , Consumo de Oxigênio , Ratos , Ratos Wistar , Glândula Tireoide/fisiologia , Vitamina E/metabolismo
12.
Mol Cell Endocrinol ; 341(1-2): 55-62, 2011 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-21664427

RESUMO

Thyronamines T(0)AM and T(1)AM are naturally occurring decarboxylated thyroid hormone derivatives. Their in vivo administration induces effects opposite to those induced by thyroid hormone, including lowering of body temperature. Since the mitochondrial energy-transduction apparatus is known to be a potential target of thyroid hormone and its derivatives, we investigated the in vitro effects of T(0)AM and T(1)AM on the rates of O(2) consumption and H(2)O(2) release by rat liver mitochondria. Hypothyroid animals were used because of the low levels of endogenous thyronamines. We found that both compounds are able to reduce mitochondrial O(2) consumption and increase H(2)O(2) release. The observed changes could be explained by a partial block, operated by thyronamines, at a site located near the site of action of antimycin A. This hypothesis was confirmed by the observation that thyronamines reduced the activity of Complex III where the site of antimycin action is located. Because thyronamines exerted their effects at concentrations comparable to those found in hepatic tissue, it is conceivable that they can affect in vivo mitochondrial O(2) consumption and H(2)O(2) production acting as modulators of thyroid hormone action.


Assuntos
Fígado/metabolismo , Tironinas/farmacologia , Animais , Fracionamento Celular , Transporte de Elétrons/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Fígado/efeitos dos fármacos , Malatos/metabolismo , Masculino , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Inibidores da Monoaminoxidase/farmacologia , Oxirredução , Consumo de Oxigênio , Pargilina/farmacologia , Ácido Pirúvico/metabolismo , Ratos , Ratos Wistar , Ácido Succínico/metabolismo
13.
Clin Nephrol ; 75(6): 518-23, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21612755

RESUMO

OBJECTIVES: Renal dysfunction is a common complication in human immunodeficiency virus (HIV)-infected patients and can be attributed to direct viral damage, comorbidities or drug toxicity. The aim of this study was to assess cross-sectional correlates of renal damage in a contemporary European cohort of patients. METHODS: We performed a case-control study from our cohort of 750 HIV-infected adults over a period of 5 months. We assessed renal damage by either proteinuria (≥+ on urine dipstick), reduced creatinine clearance (< 60 ml/min) or reduced estimated glomerular filtration rate (eGFR) of < 60 ml/ min/1.73 m2. The characteristics of cases and controls were compared in analysis and in multivariate logistic regression models with stepwise selection. RESULTS: Approximately 50% of the screened 106 patients had a qualifying abnormality. Altogether, we identified 55 cases with 110 age- and gender-matched controls. Mean eGFR was 90.7 (4.8) for cases vs. 106.1 (2.3) ml/min/1.73 m2 for controls (p = 0.001). Cases had a longer duration of HIV infection, more complex regimen, longer exposure to antiretroviral therapy and a more frequent diagnosis of acquired immune-deficiency syndrome (AIDS) and hepatitis C virus (HCV) infection. In the logistic multivariate model, renal damage remained significantly associated with longer known duration of HIV infection (OR 2.88, 95% CI: 1.28 - 6.46, p = 0.01), AIDS defining condition (OR 1.09 95% CI: 1.03 - 1.16, p = 0.002) female gender (OR 2.01, 95% CI: 0.96 - 4.18, p = 0.06), and HCV infection (OR 2.12, 95% CI: 0.99 - 4.52, p = 0.05). CONCLUSIONS: Duration, antiretroviral regimen and coincidental HCV impacted the frequency of renal abnormalities in our patients.


Assuntos
Infecções por HIV/complicações , HIV-1 , Falência Renal Crônica/etiologia , Síndrome da Imunodeficiência Adquirida/complicações , Adulto , Fármacos Anti-HIV/efeitos adversos , Estudos de Casos e Controles , Creatinina/urina , Estudos Transversais , Feminino , Taxa de Filtração Glomerular , Hepatite C/complicações , Humanos , Itália/epidemiologia , Falência Renal Crônica/induzido quimicamente , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/virologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteinúria/diagnóstico , Fatores de Risco , Estatísticas não Paramétricas , Abuso de Substâncias por Via Intravenosa/complicações , Fatores de Tempo
14.
Exp Physiol ; 96(7): 635-46, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21527542

RESUMO

In both 3,5,3-triiodothyronine (T(3))-induced hyperthyroidism and cold-induced functional hyperthyroidism, the heart displays an increased susceptibility to oxidative challenge in vitro. Hearts from T(3)-treated rats also exhibit an increased susceptibility to ischaemia-reperfusion, a condition that raises free radical production. The present study was designed to establish whether cold-exposed rats exhibit an increased cardiac susceptibility to ischaemia-reperfusion which can be attenuated by vitamin E. The following four groups of animals were used: C, control rats (n = 8, temperature 24°C); C+VE, vitamin E-treated rats (n = 8, temperature 24°C); CE, cold-exposed rats (n = 8, temperature 4°C); and CE+VE, cold-exposed vitamin E-treated rats (n = 8, temperature 4°C). Langendorff preparations from these animals were submitted to 20 min ischaemia followed by 25 min reperfusion. At the end of the ischaemia-reperfusion protocol, homogenates and mitochondria were prepared and used for analytical procedures. With respect to control hearts, cold hearts showed a lower inotropic recovery and a higher oxidative stress, as inferred by higher levels of oxidized proteins and lipids and lower reduced glutathione levels. These changes were prevented when cold rats were treated with vitamin E. Evidence was also obtained that mitochondria are involved in the tissue derangement of cold hearts. Indeed, they display a faster production of reactive oxygen species, which causes mitochondrial oxidative damage and functional decline that parallel the tissue dysfunction. Moreover, vitamin E-linked improvement of tissue function was associated with a lower oxidative damage and a restored function of mitochondria. Finally, the mitochondrial population composition and Ca(2+)-induced swelling data indicate that the decline in mitochondrial function is in part due to a decrease in the amount of the highly functional heavy mitochondria linked to their higher susceptibility to oxidative damage and swelling. In conclusion, our work shows that vitamin E treatment attenuates harmful side-effects of the cardiac response to cold, such as oxidative damage and susceptibility to oxidants, thus preserving mitochondrial function and tissue recovery from ischaemia-reperfusion.


Assuntos
Temperatura Baixa , Mitocôndrias Cardíacas/fisiologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Vitamina E/farmacologia , Animais , Cálcio/farmacologia , Coração/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Hipertireoidismo/fisiopatologia , Masculino , Mitocôndrias Cardíacas/efeitos dos fármacos , Dilatação Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Consumo de Oxigênio/fisiologia , Ratos , Ratos Wistar
15.
Eur J Gynaecol Oncol ; 31(4): 411-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20882883

RESUMO

The objectives of this study were to evaluate the evolution of a LSIL associated with p16INK4a overexpression and on the basis of this association, identify patients who would benefit from immediate treatment rather than a later follow-up. Two hundred and forty-five cervical biopsies were studied: 199 (81.2%) were classified CIN 1, 18 (7.4%) CIN 2/3 while 28 (11.4%) were not pathological. Immunohistochemistry revealed that 22 of the 217 CIN samples (11%) were positive for the p16INK4a antigen. The results of the PCR-ELISA for the research and typing of the HPV in these 22 cases were: 14 (63.6%) HPV 16; three (13.6%) HPV 31; 2 (9%) HPV 33; one (4.6%) HPV 43; one (4.6%) HPV 45; one (4.6%) HPV 18. Colposcopic and histological tests performed at four- and eight-month follow-ups in these patients revealed worsening of the initial lesion. Hence, we conclude that immediate therapy would be of benefit in these patients.


Assuntos
Proteínas de Neoplasias/análise , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Biomarcadores Tumorais/análise , Inibidor p16 de Quinase Dependente de Ciclina , Feminino , Humanos , Papillomaviridae/isolamento & purificação , Neoplasias do Colo do Útero/terapia , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/terapia , Displasia do Colo do Útero/virologia
16.
J Exp Biol ; 213(Pt 17): 2899-911, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20709918

RESUMO

Exposure of homeothermic animals to low environmental temperature is associated with oxidative stress in several body tissues. Because cold exposure induces a condition of functional hyperthyroidism, the observation that tissue oxidative stress also happens in experimental hyperthyroidism, induced by 3,5,3'-triiodothyronine (T(3)) treatment, suggests that this hormone is responsible for the oxidative damage found in tissues from cold-exposed animals. Examination of T(3)-responsive tissues, such as brown adipose tissue (BAT) and liver, shows that changes in factors favoring oxidative modifications are similar in experimental and functional hyperthyroidism. However, differences are also apparent, likely due to the action of physiological regulators, such as noradrenaline and thyroxine, whose levels are different in cold-exposed and T(3)-treated animals. To date, there is evidence that biochemical changes underlying the thermogenic response to cold as well as those leading to oxidative stress require a synergism between T(3)- and noradrenaline-generated signals. Conversely, available results suggest that thyroxine (T(4)) supplies a direct contribution to cold-induced BAT oxidative damage, but contributes to the liver response only as a T(3) precursor.


Assuntos
Temperatura Baixa , Resposta ao Choque Frio/fisiologia , Hipertireoidismo/metabolismo , Estresse Oxidativo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/patologia , Animais
17.
J Endocrinol ; 205(3): 279-89, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20360308

RESUMO

Specific tissue responses to thyroid hormone are mediated by the hormone binding to two subtypes of nuclear receptors, TRalpha and TRbeta. We investigated the relationship between TRbeta activation and liver oxidative metabolism in hypothyroid rats treated with equimolar doses of triiodothyronine (T(3)) and GC-1, a TRbeta agonist. T(3) treatment produces increases in O(2) consumption and H(2)O(2) production higher than those elicited by GC-1. The greater effects of T(3) on oxidative processes are linked to the higher hormonal stimulation of the content of respiratory chain components including autoxidizable electron carriers as demonstrated by the measurement of activities of respiratory complexes and H(2)O(2) generation in the presence of respiratory inhibitors. It is conceivable that these differential effects are dependent on the inability of GC-1 to stimulate TRalpha receptors that are likely involved in the expression of some components of the respiratory chain. The greater increases in reactive oxygen species production and susceptibility to oxidants exhibited by mitochondria from T(3)-treated rats are consistent with their higher lipid and protein oxidative damage and lower resistance to Ca(2)(+) load. The T(3) and GC-1 effects on the expression levels of nuclear respiratory factor-1 and -2 and peroxisome proliferator-activated receptor-gamma coactivator-1alpha suggest the involvement of respiratory factors in the agonist-linked changes in mitochondrial respiratory capacities and H(2)O(2) production.


Assuntos
Acetatos/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Fenóis/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Tri-Iodotironina/farmacologia , Animais , Fator de Transcrição de Proteínas de Ligação GA/metabolismo , Peróxido de Hidrogênio/metabolismo , Masculino , Modelos Animais , Fator 1 Nuclear Respiratório/metabolismo , Oxirredução/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , PPAR gama/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
18.
Mol Cell Endocrinol ; 305(1-2): 22-9, 2009 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-19433258

RESUMO

We studied liver oxidative capacity and O2 consumption in hypothyroid rats treated for 10 days with T4, or T3, or treated for 10 days with T3 and exposed to cold for the last 2 days. The metabolic response of homogenates and mitochondria indicated that all treatments increased the synthesis of respiratory chain components, whereas only the cold-induced mitochondrial proliferation. Determination of mRNA and protein expression of transcription factor activators, such as NRF-1 and NRF-2, and coactivators, such as PGC-1, showed that mRNA levels, except PGC-1 ones, were not related to aerobic capacities. Conversely, a strong correlation was found between cytochrome oxidase activity and PGC-1 or NRF-2 protein levels. Such a correlation was not found for NRF-1. Our results strongly support the view that in rat liver PGC-1 and NRFs are responsible for the iodothyronine-induced increases in respiratory chain components, whereas their role in cold-induced mitochondrial proliferation needs to be further on clarified.


Assuntos
Fígado/metabolismo , Fator 1 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo , Animais , Temperatura Baixa , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Fígado/efeitos dos fármacos , Masculino , Mitocôndrias/metabolismo , Oxirredução , Consumo de Oxigênio , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Tiroxina/farmacologia , Tri-Iodotironina/farmacologia
19.
J Exp Biol ; 212(Pt 7): 986-93, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19282495

RESUMO

We compared the changes in tissue aerobic metabolism and oxidative damage elicited by hypothyroid rat treatment with T3 and its analog GC-1. Aerobic capacities, evaluated by cytochrome oxidase activities, were increased more by T3 than by GC-1. Furthermore, the response of the tissues to T3 was similar, whereas the response to GC-1 was high in liver, low in muscle and scarce in heart. Both treatments induced increases in ADP-stimulated O2 consumption, which were consistent with those in aerobic capacities. However, unlike T3, GC-1 differentially affected pyruvate/malate- and succinate-supported respiration, suggesting that respiratory chain components do not respond as a unit to GC-1 stimulation. According to the positive relationship between electron carrier levels and rates of mitochondrial generation of oxidative species, the most extensive damage to lipids and proteins was found in T3-treated rats. Examination of antioxidant enzyme activities and scavenger levels did not clarify whether oxidative damage extent also depended on different antioxidant system effectiveness. Conversely, the analysis of parameters determining tissue susceptibility to oxidants showed that pro-oxidant capacity was lower in GC-1- than in T3-treated rats, while antioxidant capacity was similar in treatment groups. Interestingly, both agonists decreased serum cholesterol levels, but only GC-1 restored euthyroid values of heart rate and indices of tissue oxidative damage, indicating that GC-1 is able to lower cholesterolemia, bypassing detrimental effects of T3.


Assuntos
Acetatos/metabolismo , Metabolismo Energético/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Fenóis/metabolismo , Receptores beta dos Hormônios Tireóideos/antagonistas & inibidores , Tri-Iodotironina/metabolismo , Acetatos/farmacologia , Análise de Variância , Animais , Calorimetria , Eletrocardiografia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético/efeitos dos fármacos , Coração/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Músculo Esquelético/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Consumo de Oxigênio/fisiologia , Fenóis/farmacologia , Ratos , Ratos Wistar , Tri-Iodotironina/farmacologia
20.
IEEE Trans Image Process ; 17(4): 528-38, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18390361

RESUMO

We propose a novel algorithm, referred to as enhanced bounded correlation (EBC), that significantly reduces the number of computations required to carry out template matching based on normalized cross correlation (NCC) and yields exactly the same result as the full search algorithm. The algorithm relies on the concept of bounding the matching function: finding an efficiently computable upper bound of the NCC rapidly prunes those candidates that cannot provide a better NCC score with respect to the current best match. In this framework, we apply a succession of increasingly tighter upper bounding functions based on Cauchy-Schwarz inequality. Moreover, by including an online parameter prediction step into EBC, we obtain a parameter free algorithm that, in most cases, affords computational advantages very similar to those attainable by optimal offline parameter tuning. Experimental results show that the proposed algorithm can significantly accelerate a full-search equivalent template matching process and outperforms state-of-the-art methods.


Assuntos
Algoritmos , Inteligência Artificial , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Técnica de Subtração , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Estatística como Assunto
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