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1.
Bioresour Technol ; 319: 124078, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33254443

RESUMO

Hyperthermophile bioelectrochemical systems are seldom investigated although their superior control of microbial consortium and thermodynamic advantages. Hyperthermophilic Thermotogales, for instance, are able to produce hydrogen and lactic acid from wastes better than mesophilic bacteria. Here, the electrostimulation of Thermotoga neapolitana in single-chamber electrochemical bioreactors is studied. The glucose fermentation under CO2 pressure, as model metabolism, was tested at 80 °C. Results show that a dynamic polarization (±0.8 to ±1.2 V) drives glucose fermentation and biofilm stasis on electrodes. Under this condition, production of lactic acid (33 vs 12 mM) and yields of acetate and hydrogen (with lactic/acetic acid ratio of 1.18) were higher than those achieved with static polarization or open-circuit. Dynamic polarization is possibly exploitable to stimulate T. neapolitana in a hyperthermophile electrochemical system for various applications including control of power-to-gas processes or production of value-added products (hydrogen and lactic acid) from sugary wastes.


Assuntos
Terapia por Estimulação Elétrica , Thermotoga neapolitana , Archaea , Fermentação , Hidrogênio , Consórcios Microbianos
2.
PLoS One ; 13(4): e0194922, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29617435

RESUMO

BACKGROUND AND AIM: There are several prognostic systems that address different aspects of the patient and the tumour and can guide the management of patients with hepatocellular carcinoma (HCC). This study aimed to evaluate and compare the eight staging systems for a group of patients in a public service in Brazil. METHODS: Patients with HCC were retrospectively analysed between 2000 and 2012. The prognostic systems Okuda, The Cancer of the Liver Italian Program (CLIP), the Chinese University Prognostic Index (CUPI), Groupe d'Etude et de Traitément du Carcinome Hepatocellulaire (GRETCH), the modified TNM-based Japan Integrated Score (JIS) combined with alpha-fetoprotein and Child-Turcotte-Pugh (CTP), the TNM system, and the Barcelona Clinic Liver Cancer Classification (BCLC) were applied to these patients and compared through model fit measurements, likelihood scores, and the Akaike Information Criterion (AIC). RESULTS: A total of 247 patients were studied. The average survival time was 60 months. The TNM, Okuda, CLIP, GRETCH, modified JIS, and BCLC systems were well correlated with one another and individually important to the prediction of survival among the patients studied. However, in the statistical analysis, the CUPI delivered the best predictive performance (AIC = 566; log-likelihood = -281,240). CONCLUSION: Although the CUPI system was demonstrated to be the most appropriate HCC staging system for the studied population, the choice of an ideal system is a controversial subject, and future studies with larger numbers of patients are necessary for the validation of the CUPI system as the method of choice for other populations.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Estadiamento de Neoplasias/métodos , Idoso , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Niacinamida/análogos & derivados , Niacinamida/uso terapêutico , Compostos de Fenilureia/uso terapêutico , Prognóstico , Estudos Retrospectivos , Sorafenibe , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , alfa-Fetoproteínas/análise
3.
Br J Radiol ; 88(1047): 20140477, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25652643

RESUMO

OBJECTIVE: To evaluate the effectiveness of the iPad (Apple Inc., Cupertino, CA) for two-dimensional (2D) reading of CT angiography (CTA) studies performed for suspected acute non-variceal gastrointestinal bleeding. METHODS: 24 CTA examinations of patients with suspected acute gastrointestinal bleeding confirmed (19/24, 79.2%) or ruled out (5/24, 20.8%) by digital subtraction angiography (DSA) were retrospectively reviewed by three independent readers on a commercial picture archiving communication system (PACS) workstation and on an iPad with Retina Display® 64 GB (Apple Inc.). The time needed to complete reading of every CTA examination was recorded, as well as the rate of detection of arterial bleeding and identification of suspected bleeding arteries on both devices. RESULTS: Overall, the area under the receiver operating characteristic curve, sensitivity, specificity, positive- and negative-predictive values for bleeding detection were not significantly different while using the iPad and workstation (0.774 vs 0.847, 0.947 vs 0.895, 0.6 vs 0.8, 0.9 vs 0.944 and 0.750 vs 0.667, respectively; p > 0.05). In DSA-positive cases, the iPad and workstation allowed correct identification of the bleeding source in 17/19 cases (89.5%) and 15/19 cases (78.9%), respectively (p > 0.05). Finally, the time needed to complete reading of every CTA study was significantly shorter using the iPad (169 ± 74 vs 222 ± 70 s, respectively; p < 0.01). CONCLUSION: Compared with a conventional PACS workstation, iPad-based preliminary 2D reading of CTA studies has comparable diagnostic accuracy for detection of acute gastrointestinal bleeding and can be significantly faster. ADVANCES IN KNOWLEDGE: The iPad could be used by on-call interventional radiologists for immediate decision on percutaneous embolization in patients with suspected acute gastrointestinal bleeding.


Assuntos
Angiografia Digital/métodos , Computadores de Mão , Hemorragia Gastrointestinal/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Tomografia Computadorizada Multidetectores/métodos , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos
4.
Appl Microbiol Biotechnol ; 99(2): 1001-10, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25467925

RESUMO

Two-stage process based on photofermentation of dark fermentation effluents is widely recognized as the most effective method for biological production of hydrogen from organic substrates. Recently, it was described an alternative mechanism, named capnophilic lactic fermentation, for sugar fermentation by the hyperthermophilic bacterium Thermotoga neapolitana in CO2-rich atmosphere. Here, we report the first application of this novel process to two-stage biological production of hydrogen. The microbial system based on T. neapolitana DSM 4359(T) and Rhodopseudomonas palustris 42OL gave 9.4 mol of hydrogen per mole of glucose consumed during the anaerobic process, which is the best production yield so far reported for conventional two-stage batch cultivations. The improvement of hydrogen yield correlates with the increase in lactic production during capnophilic lactic fermentation and takes also advantage of the introduction of original conditions for culturing both microorganisms in minimal media based on diluted sea water. The use of CO2 during the first step of the combined process establishes a novel strategy for biohydrogen technology. Moreover, this study opens the way to cost reduction and use of salt-rich waste as feedstock.


Assuntos
Fermentação , Ácido Láctico/metabolismo , Meios de Cultura , Glucose/metabolismo , Hidrogênio/metabolismo , Modelos Moleculares , Rodopseudomonas/metabolismo , Thermotoga neapolitana/metabolismo
5.
Eur J Gynaecol Oncol ; 33(1): 96-100, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22439415

RESUMO

BACKGROUND: Desmoplastic small round cell tumor (DSRCT) is a rare sarcoma tumor affecting mainly young adult males. It rarely has an ovarian involvement. CASE: A 29-year-old woman presented to her gynecologist for amenorrhoea. The laboratory results demonstrated a menopausal status and the ultrasound revealed a large mass of the right ovary. The right ovary was completely removed by laparoscopy. Pathology, cytology and immunochemistry revealed a DSRCT. In January 2009 a left salpingo-oophorectomy and a right salpingectomy were performed via laparoscopy. After 35 months from diagnosis there was no clinical evidence of disease recurrence. CONCLUSION: DSRCT is a rare ovarian tumor in adolescence with a general poor outcome. Every ovarian mass regardless of age should be approached with caution.


Assuntos
Biomarcadores Tumorais/metabolismo , Tumor Desmoplásico de Pequenas Células Redondas/diagnóstico , Neoplasias Ovarianas/diagnóstico , Adulto , Amenorreia/etiologia , Quimioterapia Adjuvante , Tumor Desmoplásico de Pequenas Células Redondas/metabolismo , Tumor Desmoplásico de Pequenas Células Redondas/terapia , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/terapia
6.
Gynecol Endocrinol ; 28(3): 166-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21846179

RESUMO

Both quantitative and qualitative aspects of the ovarian reserve are inversely related to age, hence the relationship existing between low quantity and low quality may be only indirect and depending on their strong relationship with the third variable, namely women's age. However the possibility exists that they may also be directly related. The objective of this study was to investigate the relationship between ovarian reserve and female reproductive outcome. Eight published studies reporting histological data on the human ovaries have been carefully reviewed. Only studies where the reproductive history of women was reported have been included for the analysis. The non-growing follicle count was plotted versus age and the best fit line through the data was calculated. All patients were assigned as to be above or below the calculated median hence differentiating women with high or low ovarian reserve for their age. A similar number of pregnancies ended in miscarriage in women with low and high ovarian reserve. The number of deliveries per woman in both the groups was not statistically different. The results of the study do not support the hypothesis that quality and quantity of the follicular pool are directly related.


Assuntos
Envelhecimento/fisiologia , Folículo Ovariano/crescimento & desenvolvimento , Reprodução/fisiologia , Aborto Espontâneo/epidemiologia , Adulto , Feminino , Humanos , Folículo Ovariano/anatomia & histologia , Gravidez
7.
Q J Nucl Med Mol Imaging ; 55(6): 603-19, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22231581

RESUMO

The present review is aimed at updating the reader with the current role of computed tomography (CT) and magnetic resonance imaging (MRI) in the evaluation of tumor response, contextualizing the imaging methods advantages and limitations. CT has been the most frequent and widely adopted diagnostic tool. The main advantages of such method include wide availability, high reproducibility, capability to contemporarily evaluate soft tissues, bone and lung parenchyma, besides being easy to perform. Its main limitation is related to the use of ionizing radiation. MRI has emerged as a feasible alternative to CT, particularly in patients with contraindications to the use of iodinated contrast agents, with advantages related to its high soft tissues contrast. The disadvantages are based on its operational complexity and the many technical variables involved which may influence and compromise the reproducibility and broad implementation of the method. New criteria for evaluation of tumor response have recently been proposed, contemplating lately developed drugs and therapeutic strategies that demand the utilization of functional parameters. In this context, the technological developments incorporated in the CT and MRI imaging techniques, such as perfusion analysis, diffusion studies (DW-RM) and MR spectroscopy (MRS), among others, have provided relevant information regarding the tumor response to targeted therapies, anticipating dimensional alterations and guiding physicians in the course of the treatment. Despite such developments, further efforts are needed to establish reproducible protocols, functional response criteria and time intervals for response evaluation in order to allow a definitive incorporation of these new technologies in the assessment of tumor response.


Assuntos
Imageamento por Ressonância Magnética/tendências , Imagem Molecular/tendências , Neoplasias/diagnóstico , Neoplasias/terapia , Avaliação de Resultados em Cuidados de Saúde/tendências , Técnica de Subtração/tendências , Tomografia Computadorizada por Raios X/tendências , Humanos , Espectroscopia de Ressonância Magnética/métodos , Resultado do Tratamento
8.
Dentomaxillofac Radiol ; 39(8): 494-500, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21062943

RESUMO

OBJECTIVES: The aims of this study were to evaluate the visibility of the lateral pterygoid muscle (LPM) in temporomandibular joint (TMJ) images obtained by MRI, using different projections and to compare image findings with clinical symptoms of patients with and without temporomandibular disorders (TMD). METHODS: In this study, LPM images of 50 participants with and without TMDs were investigated by MRI. The images of the LPM in different projections of 100 TMJs from 35 participants (70 TMJs) with and 15 participants (30 TMJs) without clinical signs and symptoms of TMD were visible and analysed. RESULTS: The oblique sagittal and axial images of the TMJ clearly showed the LPM. Hypertrophy (1.45%), atrophy (2.85%) and contracture (2.85%) were the abnormalities found in the LPM. TMD signs, such as hypermobility (11.4%), hypomobility (12.9%) and disc displacement (20.0%), could be seen in TMJ images. Related clinical symptoms, such as pain (71.4%), articular sounds (30.4%), bruxism (25.7%) and headache (22.9%), were observed. CONCLUSIONS: Patients with TMD can present with alterations in the LPM thickness. Patients without TMD also showed alterations, such as atrophy and contracture, in TMJ images. Recognition of alterations in the LPM will improve our understanding of clinical symptoms and pathophysiology of TMD, and may lead to a more specific diagnosis of these disorders.


Assuntos
Imageamento por Ressonância Magnética/métodos , Músculos Pterigoides/patologia , Síndrome da Disfunção da Articulação Temporomandibular/patologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Contratura/patologia , Feminino , Humanos , Luxações Articulares/patologia , Instabilidade Articular/patologia , Masculino , Atrofia Muscular/patologia , Estudos Prospectivos , Amplitude de Movimento Articular , Articulação Temporomandibular/patologia
9.
Acta Radiol ; 48(2): 125-34, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17354130

RESUMO

PURPOSE: To evaluate the hepatosplenic manifestations and the portal venous system in patients with chronic infection by Schistosoma mansoni. MATERIAL AND METHODS: A cross-sectional observational study was performed in 28 patients with chronic hepatosplenic schistosomiasis submitted to magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of the abdomen. Images were interpreted independently by two radiologists to determine the reproducibility of image interpretation and who evaluated the presence of morphological alterations in the liver and spleen, such as hepatosplenomegaly, hepatic fissure widening, periportal fibrosis, and the presence of siderotic nodules. Interobserver and intra-observer agreement were measured with the kappa and intraclass correlation tests. Evaluation of venous collateral pathways and portal and splenic veins was done in consensus by both examiners. RESULTS: Observers identified enlargement of the left lobe (78.5-92.8%) and caudate-to-right-lobe ratio (78.5-92.8%), irregularity of hepatic contours (89.2-96.4%), fissure widening (89.2-100%), and splenic siderotic nodules (84.2%). Splenomegaly, heterogeneity of hepatic parenchyma, peripheral hepatic vessels, and periportal fibrosis were observed in 100% of patients. MRI findings presented almost perfect interobserver (kappa = 0.65-1) and intra-observer (kappa = 0.73-1 for observer 1, and kappa = 0.65-1 for observer 2) agreement for the variables analyzed. MRA showed the presence of collateral pathways in the majority of patients (71.4%) along with widening of portal and splenic veins. CONCLUSION: Using MRI, hepatosplenic alterations in schistosomiasis are characterized by heterogeneity of hepatic parenchyma, presence of peripheral perihepatic vessels, periportal fibrosis, splenomegaly, siderotic nodules, and the presence of venous collateral pathways.


Assuntos
Hepatopatias Parasitárias/diagnóstico , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Esquistossomose mansoni/diagnóstico , Esplenopatias/diagnóstico , Esplenopatias/parasitologia , Adulto , Doença Crônica , Estudos Transversais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
10.
Rev Port Pneumol ; 11(5): 477-85, 2005.
Artigo em Português | MEDLINE | ID: mdl-16288346

RESUMO

Pleural and pulmonary asbestos-related diseases range from benign conditions, like pleural effusion and pleural plaques, to some neoplasias, such as lung cancer and malignant mesothelioma. Pleural effusion is the earliest finding after asbestos exposure, but the imaging findings are not specific. Diffuse pleural thickening involves the visceral pleura and pleural plaques are considered to be hallmarks of exposure. Asbestosis is the pulmonary fibrosis due to asbestos. Rounded atelectasis is a peripheral lung collapse in these individuals, generally related to pleural disease. Some neoplasias, like lung carcinoma and pleural mesothelioma, are more prevalent in asbestos-exposed subjects. The aim of this essay is to illustrate the main imaging findings of asbestos-related diseases.


Assuntos
Amianto/efeitos adversos , Asbestose/diagnóstico por imagem , Doenças Pleurais/diagnóstico por imagem , Doenças Pleurais/etiologia , Humanos , Radiografia
11.
Rev Port Pneumol ; 11(5): 487-97, 2005.
Artigo em Português | MEDLINE | ID: mdl-16288347

RESUMO

Pleural plaques (PP) are considered to be hallmarks of asbestos exposure. They constitute focal thickenings of the pleura and are commonly seen in patients without lung disease. They can involve parietal, diaphragmatic and mediastinal pleura. Chest x-ray is frequently used for PP diagnosis, but computed tomography, especially when used the high-resolution technique, is the imaging exam with the greatest sensibility and specificity. PP are almost always asymptomatic, but there are some controversial about their relationship with asbestos exposure indexes, pulmonary functional alterations and risk of neoplasias.


Assuntos
Amianto/efeitos adversos , Doenças Pleurais/etiologia , Diagnóstico Diferencial , Humanos , Doenças Pleurais/diagnóstico por imagem , Doenças Pleurais/patologia , Doenças Pleurais/fisiopatologia , Radiografia
12.
Transplant Proc ; 36(4): 947-8, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15194328

RESUMO

OBJECTIVE: The aim of our study was to evaluate the role of magnetic resonance cholangiography (MRC) in the diagnosis of biliary tract complications (BC) after orthotopic liver transplantation (OLT). MATERIALS AND METHODS: Among 21 OLT patients who underwent routine follow-up MRC using a breath-hold T2-weighted turbo spin-echo sequence with half-Fourier acquisition (HASTE), 5 had an elevated serum alkaline phosphatase level. Diagnostic confirmation was obtained with endoscopic retrograde cholangiography (ERC) (n = 11), surgery (n = 3), or clinical and laboratory follow-up of at least 1 year (n = 8). RESULTS: In 13 patients, no abnormality of the biliary tract was detected using MRC. In 8 patients, anastomotic strictures were diagnosed, 7 of which were confirmed at surgery or using ERC. One patient with normal findings at MRC and abnormal liver function test results was found to have a stricture at ERC. All patients with normal MRC and liver function tests had 1 year of uneventful follow-up and were considered true-negative cases. We found that MRC had 87.5% sensitivity, 92.3% specificity, 87.5% positive predictive value, 92.3% negative predictive value, and 90.4% accuracy for the diagnosis of BC. CONCLUSION: MRC is a valuable examination to detect BC after OLT. It provides useful information for planning interventional procedures.


Assuntos
Colangiografia , Doenças da Vesícula Biliar/diagnóstico por imagem , Transplante de Fígado/efeitos adversos , Angiografia por Ressonância Magnética , Humanos , Complicações Pós-Operatórias/diagnóstico por imagem , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos
13.
Bone ; 31(2): 269-75, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12151078

RESUMO

Bone formation and remodeling require continuous generation of osteoprogenitor cells from bone marrow stromal cells (MSC), which generate and respond to a variety of growth factors with putative roles in hematopoiesis and mesenchymal differentiation. In this study we examine the interaction of two such factors on the maturation of skeletal components. We previously reported that these factors, hepatocyte growth factor (HGF) and 1,25-dihydroxyvitamin D(3) (vitD(3)), act together to increase alkaline phosphatase in chondroblasts. We now describe the cooperative effect of these agents on MSC isolated and cultured from human vertebral bone marrow. MSC (passages 3-9) isolated from bone marrow cells of human vertebrae (T1-L5) from 22-36-year-old normal donors were first expanded in vitro and then plated in the presence or absence of 10 ng/mL HGF and/or 10 nmol/L vitD(3), for 7-18 days. HGF treatment increased cell proliferation 2.5-fold, with no effect on alkaline phosphatase activity. Whereas vitD(3) treatment inhibited cell growth by 50%, alkaline phosphatase activity was stimulated eightfold, although no mineralization was observed. HGF together with vitD(3) increased cell proliferation 1.5-fold and alkaline phosphatase activity 13-fold over untreated control. Moreover, mineralization was detected only with this combination. Our findings provide evidence that HGF in concert with vitamin D may promote growth and differentiation of human MSC into osteogenic cells.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Colecalciferol/farmacologia , Fator de Crescimento de Hepatócito/farmacologia , Osteoblastos/efeitos dos fármacos , Adulto , Fosfatase Alcalina/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/enzimologia , Contagem de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Humanos , Masculino , Osteoblastos/citologia , Osteoblastos/enzimologia , Coluna Vertebral/citologia , Coluna Vertebral/efeitos dos fármacos , Coluna Vertebral/enzimologia , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/enzimologia
14.
Biochem Biophys Res Commun ; 285(5): 1259-66, 2001 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-11478793

RESUMO

Few therapeutic treatment options are available for patients suffering from metastatic androgen-independent prostate cancer. We investigated the ability of the estrogen metabolite 2-methoxyestradiol to inhibit the proliferation of a variety of human prostate cancer cell lines in vitro and to inhibit the growth of androgen-independent prostate cancer in a transgenic mouse model in vivo. Our results showed that 2-methoxyestradiol is a powerful growth inhibitor of LNCaP, DU 145, PC-3, and ALVA-31 prostate cancer cells. Cell flow cytometry of 2-methoxyestradiol-treated DU 145 cells showed a marked accumulation of cells in the G2/M phase of the cell cycle and an increase in the sub-G1 fraction (apoptotic). In addition, staining for annexin V, changes in nuclear morphology, and inhibition of caspase activity support a role for apoptosis. More importantly, we showed that 2-methoxyestradiol inhibits prostate tumor progression in the Ggamma/T-15 transgenic mouse model of androgen-independent prostate cancer without toxic side effects. These results in cell culture and an animal model support investigations into the clinical use of 2-methoxyestradiol in patients with androgen-independent prostate cancer.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Estradiol/farmacologia , Fase G2/efeitos dos fármacos , Mitose/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , 2-Metoxiestradiol , Administração Oral , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Anexina A5/análise , Antineoplásicos/administração & dosagem , Inibidores de Caspase , Divisão Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Relação Dose-Resposta a Droga , Implantes de Medicamento , Resistencia a Medicamentos Antineoplásicos , Inibidores Enzimáticos/farmacologia , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Citometria de Fluxo , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Neoplasias da Próstata/química , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas
15.
Sao Paulo Med J ; 119(3): 110-3, 2001 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-11391453

RESUMO

CONTEXT: The relevance of colorectal adenocarcinoma lies in its high incidence, with the liver being the organ most frequently affected by distant metastases. Liver metastases occur in 40 to 50% of patients with colorectal adenocarcinoma, accounting for approximately 80% of deaths in the first three postoperative years. Nevertheless, despite this, they are occasionally susceptible to curative treatment. OBJECTIVE: The present investigation focused on the relationship between the level of carcinoembryonic antigen (CEA) in gallbladder bile and the presence of liver metastases secondary to colorectal adenocarcinoma. DESIGN: Diagnostic test study. SETTING: Surgical Gastroenterology Discipline at the São Paulo Hospital, São Paulo, Brazil. SAMPLE: Forty-five patients with colorectal adenocarcinoma were studied, 30 without liver metastases (group I), and 15 with liver metastases (group II). Diagnosis of liver metastases was made through computed tomography, magnetic resonance imaging and computed tomography during arterial portography. Samples of peripheral blood, portal system blood, and gallbladder bile were collected from patients during the surgical procedure. A control group composed of 18 organ donors underwent the same material collection procedures. CEA level determination was made through fluoroimmunoassay. RESULTS: Mean CEA value in peripheral serum was 2.0 ng/ml (range: 0.7 to 3.8 ng/ml) in the control group, 11.4 ng/ml (range: 0.5 to 110.3 ng/ml) in group I, and 66.0 ng/ml (range: 2.1 to 670 ng/ml) in group II. In the portal system, serum mean values found were 1.9 ng/ml (range: 0.4 to 5.0 ng/ml) in the control group, 15.3 ng/ml (range: 0.8 to 133.3 ng/ml) in group I, and 70.8 ng/ml (range: 1.8 to 725 ng/ml) in group II. Mean values found in gallbladder bile were 4.1 ng/ml (range: 1.0 to 8.6 ng/ml) in the control group, 14.3 ng/ml (range: zero to 93.0 ng/ml) in group I, and 154.8 ng/ml (range: 14.0 to 534.7 ng/ml) in group II. CONCLUSIONS: The CEA level in gallbladder bile is elevated in patients with liver metastases. Determination of CEA both in peripheral serum and in gallbladder bile enabled patients with liver metastases to be distinguished from those without such lesions. The level of CEA in gallbladder bile, however, seems to lead to a more accurate diagnosis of liver metastases secondary to colorectal adenocarcinoma.


Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/secundário , Bile/química , Antígeno Carcinoembrionário/análise , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Adenocarcinoma/sangue , Adulto , Idoso , Antígeno Carcinoembrionário/sangue , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Hepáticas/sangue , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
16.
Bone ; 28(4): 362-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11336916

RESUMO

Osteoblastic cells in long-term culture undergo a phenotypic maturation process leading to extracellular matrix (ECM) production and bone nodule (BN) formation. Cell-to-cell communication via gap junctions (GJC) can be detected between osteoblastic cells within 24 h of plating. We evaluated, in long-term cultures of osteoblastic cells, the effect of inhibiting GJC on the phenotypic maturation process and the expression of specific genes associated with this process. MC3T3-E1 cells were plated, and, after 24 h (day 0), cells were exposed to 18-alpha-glycyrrhetinic acid (AGA), a nontoxic reversible inhibitor of GJC. GJC, alkaline phosphatase (AP) activity, BN formation, and the relative level of transcripts encoding osteocalcin (OC), bone sialoprotein (bSP), osteopontin (OP), collagen alpha1 type I (alpha1ICol), and elongation factor-1a (EF1a) were evaluated on day 0 and every 4-7 days thereafter through day 30. GJC was assessed by fluorescent dye transfer. Gene expression was analyzed by northern blot and semiquantitative reverse transcription-polymerase chain reaction. GJC was detectable at day 0 and increased with time in culture. AGA (100 micromol/L) strongly inhibited GJC at all timepoints tested. Moreover, AGA-exposed cells showed a dose-dependent decrease in AP activity and a delay in the appearance of BN. This delayed phenotypic expression coincided with an inhibitory effect on the expression of the osteoblast-specific genes OC and bSP. Expression of alpha1ICol mRNA was also affected, but to a lesser extent, whereas OP and EF1a were not affected. Similar results were obtained with oleamide, an additional reversible inhibitor of GJC. In contrast, cells exposed to either vehicle or 100 micromol/L glycyrrhizic acid (a noninhibitory glycoside of 18-beta-glycyrrhetinic acid) were indistinguishable from untreated cells for all parameters evaluated. We conclude that GJC inhibition interferes with the maturation process of osteoblastic cells in culture, possibly by affecting signals regulating the expression of genes involved in the maturation/differentiation of the osteoblastic phenotype.


Assuntos
Comunicação Celular , Junções Comunicantes/fisiologia , Osteoblastos/citologia , Células 3T3 , Fosfatase Alcalina/metabolismo , Animais , Sequência de Bases , Comunicação Celular/efeitos dos fármacos , Primers do DNA , Junções Comunicantes/efeitos dos fármacos , Ácido Glicirretínico/farmacologia , Camundongos , Osteoblastos/efeitos dos fármacos , Osteoblastos/enzimologia , Osteoblastos/metabolismo , Fenótipo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
J Biol Chem ; 276(17): 14133-8, 2001 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-11278824

RESUMO

Osteoblasts and adipocytes are thought to differentiate from a common stromal progenitor cell. These two phenotypically mature cell types show a high degree of plasticity, which can be observed when cells are grown under specific culture conditions. Gap junctions are abundant among osteoblastic cells in vivo and in vitro, whereas they are down-regulated during adipogenesis. Gap junctional communication (GJC) modulates the expression of genes associated with the mature osteoblastic phenotype. Inhibition of GJC utilizing 18-alpha-glycyrrhetinic acid (AGRA) blocks the maturation of pre-osteoblastic cells in vitro. Moreover, cytoplasmic lipid droplets are detectable at the end of the culture period, suggesting that GJC inhibition may favor an adipocytic phenotype. We used several human osteoblastic cell lines, as well as bone-derived primary osteoblastic cells, to show that confluent cultures of human osteoblastic cells grown under osteogenic conditions developed an adipocytic phenotype after 3 days of complete inhibition of GJC using AGRA or oleamide, two dissimilar nontoxic reversible inhibitors. Development of an adipogenic phenotype was confirmed by the accumulation of triglyceride droplets and the increase in mRNA expression of the adipocytic markers peroxisome proliferator-activated receptor gamma2 and lipoprotein lipase. Glycyrrhizic acid, a noninhibitory AGRA analog, or alpha-bromopalmitate, a nondegradable fatty acid, had no effect. Modulation of skeletal GJC may represent a new pharmacological target by which inhibition of marrow adipogenesis can take place with the parallel enhancement of osteoblastogenesis, thus providing a novel therapeutic approach to the treatment of human age-related osteopenic diseases and postmenopausal osteoporosis.


Assuntos
Adipócitos/citologia , Junções Comunicantes/fisiologia , Osteoblastos/citologia , Células 3T3 , Administração Tópica , Adolescente , Idoso , Animais , Anti-Inflamatórios/farmacologia , Northern Blotting , Diferenciação Celular , Linhagem Celular , Células Cultivadas , Citoplasma/metabolismo , Regulação para Baixo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Ácido Glicirretínico/farmacologia , Ácido Glicirrízico/farmacologia , Humanos , Lipase Lipoproteica/metabolismo , Masculino , Camundongos , Músculo Esquelético/metabolismo , Ácidos Oleicos/farmacologia , Osteossarcoma/metabolismo , Palmitatos/farmacologia , Fenótipo , RNA/metabolismo , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Coluna Vertebral/citologia , Fatores de Tempo , Fatores de Transcrição/farmacologia , Triglicerídeos/metabolismo
18.
Bone ; 28(1): 38-44, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11165941

RESUMO

Previously we showed that physiological levels of parathyroid hormone (PTH) can increase the mineralization of extracellular matrix (ECM) by osteoblast-like cells in vitro. In this study, we assess the role of gap-junctional intercellular communication (GJC) in the PTH-enhanced mineralization of ECM in MC3T3-E1 cells, a murine culture model of osteoblastic differentiation. Messenger RNA and protein for connexin 43 (Cx43), the major component of MC3T3-E1 gap junctions, and GJC increased as the cells progressed toward a mature phenotype. Immunocytochemistry showed accumulation of Cx43 at the area of close contact between cells. The timing of the PTH treatment that increased matrix mineralization in these cells coincided with the highest expression of Cx43 and GJC. Administration of 18-alpha-glycyrrhetinic acid (AGA) promptly blocked GJC in cultures of MC3T3-E1 cells in a dose-dependent and reversible manner at all times tested during the culture period. Treatment with AGA, but not with an inactive analog, reversed the PTH-induced ECM mineralization. These data suggest that GJC mediates anabolic actions of PTH related to osteoblast-mediated mineralization.


Assuntos
Calcificação Fisiológica/efeitos dos fármacos , Comunicação Celular/fisiologia , Junções Comunicantes/fisiologia , Osteoblastos/metabolismo , Hormônio Paratireóideo/farmacologia , Animais , Comunicação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Conexina 43/metabolismo , Camundongos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos
19.
J Nat Prod ; 64(1): 131-3, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11170688

RESUMO

Two new cyclic peroxides (1 and 2) and the known metabolite 3 have been found in the organic extract of the Indian sponge Acarnus bicladotylota. The structure of the new products has been assured by chemical and spectroscopic methods. The absolute stereochemistry of 1-3 has been determined by Mosher's method on the semisynthetic derivative 4.


Assuntos
Antineoplásicos/química , Furanos/química , Lactonas/química , Peróxidos/química , Poríferos/química , Animais , Antineoplásicos/isolamento & purificação , Índia , Espectroscopia de Ressonância Magnética , Peróxidos/isolamento & purificação , Espectrofotometria Infravermelho
20.
Surg Today ; 31(11): 1024-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11766075

RESUMO

We report herein the case of a 46-year-old woman investigated for recurrent acute cholangitis. Ultrasound, endoscopic retrograde cholangiopancreatography, and computed tomography scan revealed dilatation and multiple images suggestive of intrahepatic biliary stones in the ducts that drained segments V and VI of the liver. Endoscopic treatment was attempted unsuccessfully, and based on the severity of the last crisis of cholangitis a laparotomy was performed. A right hepatic lobectomy including segments V and VI was carried out without any complications, resulting in complete relief of symptoms. Pathological examination of the liver demonstrated the presence of worm nests in the liver parenchyma with chronic granulomatous lesions.


Assuntos
Ascaridíase/complicações , Colelitíase/parasitologia , Hepatectomia , Hepatopatias Parasitárias/complicações , Doença Aguda , Colangiopancreatografia Retrógrada Endoscópica , Colangite/parasitologia , Colelitíase/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade
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