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1.
Neurotoxicology ; 63: 146-154, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29031576

RESUMO

Nanotechnologies are at the center of societal interest, due to their broad spectrum of application in different industrial products. The current concern about nanomaterials (NMs) is the potential risks they carry for human health and the environment. Considering that NMs can reach bodies of water, there is a need for studying the toxic effects of NMs on aquatic organisms. Among the NMs' toxic effects on fish, the interactions between NMs and the nervous system are yet to be understood. For this reason, our goal was to assess the neurotoxicity of polyvinylpyrrolidone coated silver nanospheres [AgNS (PVP coated)] and compare their effects in relation to silver ions (Ag+) in carnivorous Hoplias intermedius fish after acute and subchronic trophic exposure through the analysis of morphological (retina), biochemical (brain) and genetic biomarkers (brain and blood). For morphological biomarkers, damage by AgNS (PVP coated) in retina was found, including morphological changes in rods, cones, hemorrhage and epithelium rupture, and also deposition of AgNS (PVP coated) in retina and sclera. In the brain biomarkers, AgNS (PVP coated) did not disturb acetylcholinesterase activity. However, lowered migration of the DNA tail in the Comet Assay of blood and brain cells was observed for all doses of AgNS (PVP coated), for both acute and subchronic bioassays, and in a dose-dependent manner in acute exposure. Ag+ also reduced the level of DNA damage only under subchronic conditions in the brain cells. In general, the results demonstrated that AgNS (PVP coated) do not cause similar effects in relation to Ag+. Moreover, the lowered level of DNA damage detected by Comet Assay suggests that AgNS (PVP coated) directly interacts with DNA of brain and blood cells, inducing DNA-DNA or DNA-protein crosslinks. Therefore, the AgNS (PVP coated) accumulating, particularly in the retina, can lead to a competitive disadvantage for fish, compromising their survival.


Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Nanosferas/toxicidade , Povidona/toxicidade , Prata/toxicidade , Acetilcolinesterase/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Peixes , Microscopia Eletrônica de Varredura , Células Fotorreceptoras/efeitos dos fármacos , Células Fotorreceptoras/ultraestrutura , Retina/citologia , Retina/efeitos dos fármacos , Retina/ultraestrutura , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/ultraestrutura , Fatores de Tempo
2.
J Viral Hepat ; 22(2): 120-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25040685

RESUMO

Hepatocellular carcinoma (HCC) may still develop in chronic hepatitis B (CHB) patients treated with lamivudine. Whether HCC rates are comparable in patients treated with the current first-line antivirals remains uncertain. We estimated the incidence and evaluated predictors of HCC in a large nationwide prospective cohort (HepNet.Greece) of HBeAg-negative CHB patients treated with entecavir. HBeAg-negative CHB patients from the same cohort who were initially treated with lamivudine were used as controls. We included 321 patients treated with entecavir for a median of 40 months and 818 patients treated initially with lamivudine for a median of 60 months. In the entecavir group, HCC developed in 4 of 321 (1.2%) patients at a median of 1.5 (range: 1.0-4.5) years, while the cumulative HCC incidence was significantly higher in cirrhotics than noncirrhotics (1, 3, 5 years: 0%, 3%, 9% vs 1%, 1%, 1%; P = 0.024) and in older patients (P = 0.026). Entecavir compared with lamivudine group patients had lower HCC incidence (1, 3, 5 years: 0.3%, 1.2%, 2.8% vs 0.7%, 3.8%, 5.6%; P = 0.024). However, in multivariable Cox regression analysis, the HCC risk was independently associated with older age (P < 0.001), male gender (P = 0.011) and cirrhosis (P = 0.025), but not with the initial agent. In conclusion, our large nationwide study indicates that the HCC risk remains increased in entecavir-treated HBeAg-negative CHB patients with cirrhosis, particularly of older age, at least for the first 5 years. The HCC risk does not seem to be significantly reduced with entecavir compared with antiviral therapy starting with lamivudine.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular/epidemiologia , Guanina/análogos & derivados , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Adulto , Estudos de Coortes , Feminino , Grécia/epidemiologia , Guanina/uso terapêutico , Humanos , Incidência , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Resultado do Tratamento
3.
Resuscitation ; 85(10): 1387-93, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25046743

RESUMO

AIM: Improved survival after cardiac arrest has placed greater emphasis on neurologic resuscitation. The purpose of this pilot study was to evaluate the relationship between cerebrovascular autoregulation and neurologic outcomes after pediatric cardiac arrest. METHODS: Children resuscitated from cardiac arrest had autoregulation monitoring during the first 72h after return of circulation with an index derived from near-infrared spectroscopy in a pilot study. The range of mean arterial blood pressure (MAP) with optimal vasoreactivity (MAPOPT) was identified. The area under the curve (AUC) of the time spent with MAP below MAPOPT and MAP deviation below MAPOPT was calculated. Neurologic outcome measures included placement of a new tracheostomy or gastrostomy, death from a primary neurologic etiology (brain death or withdrawal of support for neurologic futility), and change in the Pediatric Cerebral Performance Category score (ΔPCPC). RESULTS: Thirty-six children were monitored. Among children who did not require extracorporeal membrane oxygenation (ECMO), children who received a tracheostomy/gastrostomy had greater AUC during the second 24h after resuscitation than those who did not (P=0.04; n=19). Children without ECMO who died from a neurologic etiology had greater AUC during the first 48h than did those who lived or died from cardiovascular failure (P=0.04; n=19). AUC below MAPOPT was not associated with ΔPCPC when children with or without ECMO were analyzed separately. CONCLUSIONS: Deviation from the blood pressure with optimal autoregulatory vasoreactivity may predict poor neurologic outcomes after pediatric cardiac arrest. This experimental autoregulation monitoring technique may help individualize blood pressure management goals after resuscitation.


Assuntos
Circulação Cerebrovascular/fisiologia , Parada Cardíaca/fisiopatologia , Parada Cardíaca/terapia , Homeostase , Ressuscitação , Adolescente , Criança , Pré-Escolar , Oxigenação por Membrana Extracorpórea , Feminino , Humanos , Lactente , Masculino , Projetos Piloto
4.
J Viral Hepat ; 21(9): 624-32, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24224747

RESUMO

Peginterferon-alpha (PegIFNa) frequently causes neutropenia, mainly due to bone marrow suppression. The aim of this study was to explore factors that are associated with infections during antiviral treatment. We analysed data from 275 chronic hepatitis C (CHC) patients with compensated liver disease who underwent 318 courses of PegIFNa and ribavirin. Neutropenia was defined as neutrophils <1000 cells/µL. Mean leucocytes count significantly decreased from baseline to treatment nadir (7081 ± 2182 vs 3293 ± 1331 cells/µL, P < 0.001), while neutropenia was observed in 32% during treatment. Thirty-one infections were observed. The incidence rate for infection was assessed at 1.46 infections per 100 person-months of therapy. The hazard rate for infection did not correlate with the neutrophils' nadir or the decrease in white blood cells. In multivariate Cox's regression analysis, cirrhosis was the only factor that was significantly associated with the occurrence of infection. Our data show that the development of bacterial infections during treatment with PegIFNa and ribavirin in patients with compensated CHC is not associated with reduction or the nadir of white cells or neutrophil counts. Baseline cirrhosis is the only factor related with infection during treatment. The common practice of dose adjustment or discontinuation of interferon should be revised; careful assessment of liver damage before therapy and close monitoring during therapy are essential in all patients receiving interferon-based regimes, to minimize the detrimental consequences of infections.


Assuntos
Antivirais/uso terapêutico , Infecções Bacterianas/epidemiologia , Hepatite C Crônica/complicações , Interferon-alfa/uso terapêutico , Cirrose Hepática/complicações , Neutropenia/complicações , Ribavirina/uso terapêutico , Adolescente , Adulto , Idoso , Antivirais/efeitos adversos , Feminino , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Estudos Retrospectivos , Ribavirina/efeitos adversos , Adulto Jovem
5.
Rev. argent. radiol ; 77(3): 0-0, set. 2013. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-694929

RESUMO

Objetivos: Describir el comportamiento imagenológico del hepatocarcinoma en pacientes con cirrosis utilizando la tomografía computada multidetector (TCMD) dinámica y correlacionar los hallazgos con el grado histológico de los tumores. Materiales y métodos: Estudio retrospectivo, observacional y descriptivo, donde se evaluaron 51 nódulos de 32 pacientes trasplantados de hígado con diagnóstico de cirrosis. La anatomía patológica del explante fue utilizada como referencia y los nódulos con histología de hepatocarcinoma fueron analizados retrospectivamente en las tomografías computadas efectuadas antes del trasplante. Las tomografías se llevaron a cabo con técnica dinámica, evaluando las características más frecuentes reportadas en la literatura: realce arterial, lavado del realce, cápsula y vasos arteriales intratumorales. Resultados: Cuarenta y seis de 51 (90%) tumores mostraron realce arterial. De estos 46 tumores, 39 (85%) mostraron lavado del realce en la fase portal y/o tardía. De los 51, 5 (10%) fueron hipovasculares, 22 (43%) presentaron cápsula y 12 (24%) mostraron vasos arteriales intratumorales. La combinación de hallazgos más frecuente fue la asociación de realce arterial y lavado del realce en la fase portal-tardía (39/51 tumores: 76%), y el grado histológico más usual fue el II en 35 tumores (69%). Se hallaron asociaciones estadísticamente significativas entre el grado histológico de los tumores y los comportamientos imagenológicos realce arterial e hipovascular. Conclusión: En nuestra población, el hallazgo tomográfico de realce arterial con lavado del realce en tiempo portal y/o tardío fue observado en la mayoría de los tumores. Esto coincide con publicaciones anteriores y contribuye a fortalecer el valor de estos criterios para el diagnóstico del hepatocarcinoma...


Objectives: To describe the imagenological behavior of hepatocellular carcinoma in cirrhotic patients using a dynamic multidetector computed tomography (MDCT) technique, and correlate these fi ndings with histological tumor grades.Materials and methods: A retrospective, descriptive observational study was conducted to evaluate 51 nodules in 32 liver transplant patients diagnosed with liver cirrhosis. The pathology of liver explants was used as a reference. Nodules with hepatocellular carcinoma histopathology were retrospectively analyzed by computed tomography scans performed pre-transplant. Using a dynamic multidetector computed tomography technique, we evaluated the mos common imagenological behavior reported in the literature: arterial enhancement, washout, capsule, and intratumoral arterial vessels.Results: Forty-six of 51 (90%) tumors showed arterial enhancement. Of the 46 tumors with arterial enhancement, 39 (85%) had washout in portal-late phase. Five of 51 (10%) were hypovascular. Twenty-two of 51 (43%) had capsule and 12 of 51 (24%) showed intratumoral arterial vessels. The more frequent image combination was the combination of arterial enhancement and washout (39 of 51 tumors or 76%). The most frequent histological grade was II (35 of 51 tumors or 69%). Statistically signifi cant relationships were found between histological grade tumors and imagenological behavior: arterial enhancement and hypovascular. Conclusion: In our population, arterial enhancement with washout in portal-late phases was observed in most of the tumors. Our results are consistent with previously reported studies, demonstrating the high reliability of this imaging pattern for the diagnosis of hepatocellular carcinoma...


Assuntos
Humanos , Fibrose , Cirrose Hepática , Carcinoma Hepatocelular , Hepatite B , Hepatite C , Cirrose Hepática Alcoólica , Transplante de Fígado , Neoplasias
6.
Ecotoxicol Environ Saf ; 93: 13-21, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23623483

RESUMO

The exposure to a world-wide used herbicide atrazine (ATZ) (96h exposure to 2, 10, and 100µgL(-1)), was investigated on the freshwater fish Rhamdia quelen through a multi biomarker approach. Liver histopathology revealed leukocyte infiltration, hepatocyte vacuolization like steatosis and necrosis areas, leading to raised lesion index levels in all tested concentrations. The increase of free melanomacrophage numbers was observed. Gill filaments revealed considerable loss of the microridges on pavement cells at 10 and 100µgL(-1) of ATZ, and a significantly increased of chloride cell (CC) number and density on apical surface area at 100µgL(-1) of ATZ. CAT, GST, GPx, and GR activities were inhibited by all tested concentrations. GSH levels were reduced in individuals exposed to 100µgL(-1). Osmoregulatory function was also disturbed. We observed an increase of plasma magnesium concentrations at 10µgL(-1). Additionally the inhibition of branchial carbonic anhydrase activity was observed at 100µgL(-1). In the kidney, carbonic anhydrase activity decreased only in the group exposed to 2µgL(-1). These results suggest that ATZ, represents a potential ecotoxicological hazard and can be hepatotoxic and nephrotoxic even low concentrations. The current study was the first to show the nephrotoxic effect of ATZ in fish. Besides, in Brazil, the environmental protection agency (CONAMA) establishes that the maximum allowed level of dissolved ATZ in water is 2µgL(-1), but the present results showed that this concentration may cause histopathological, biochemical and physiological changes in R. quelen.


Assuntos
Atrazina/toxicidade , Herbicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Atrazina/metabolismo , Brasil , Catalase/metabolismo , Peixes-Gato/fisiologia , Água Doce , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Herbicidas/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Poluentes Químicos da Água/metabolismo
7.
Ecotoxicol Environ Saf ; 88: 108-16, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23211555

RESUMO

As it is the case in all animal food production systems, it is often necessary to treat farmed fish for diseases and parasites. Quite frequently, fish farmers still rely on the aggressive use of copper to control bacterial infections and infestations by ecto-parasites, and to manage the spread of diseases. The susceptibility of the neotropical fish Rhamdia quelen to copper was here evaluated at different waterborne copper concentrations (2, 7 or 11 µg Cu L(-1)) for 96 h, through a multi biomarkers approach. Liver histopathological findings revealed leukocyte infiltration, hepatocyte vacuolization and areas of necrosis, causing raised levels of lesions upon exposure to 7 and 11 µg Cu L(-1). Decreased occurrence of free melano-macrophages and increased densities of melano-macrophage centers were noted upon exposure to 11 µg Cu L(-1). Gills showed damages on their secondary lamellae already at 2 µg Cu L(-1); hypertrophy and loss of the microridges of pavement cells at 7 and 11 µg L(-1), and increased in chloride cell (CC) apical surface area (4.9-fold) and in CC density (1.5-fold) at 11 µg Cu L(-1). In the liver, catalase (CAT), glutathione peroxidase activities (GPx) and glutathione concentration (GSH) remained unchanged, compared to the control group. However, there was inhibition of 7-ethoxyresorufin-O-deethylase (EROD) at all copper concentrations tested. Glutathione reductase activity (GR) was reduced and levels of lipid peroxidation (LPO) were increased at 11 µg Cu L(-1). Glutathione S-transferase activity (GST) at 7 µg Cu L(-1) and superoxide dismutase activity (SOD) at both 7 and 11 µg Cu L(-1) were reduced. However, copper exposure did not alter brain and muscle acetylcholinesterase (AChE) activity. Osmoregulatory function was also disturbed, in agreement with the above-mentioned changes noted in the gills, as detected by plasma osmolality reduction in the group exposed to 11 µg Cu L(-1), and plasma chloride reduction at 2 µg Cu L(-1). These concentrations also, coherently, lead to inhibition of branchial carbonic anhydrase activity. In the kidney, increased carbonic anhydrase activity was measured in the groups exposed to 2 and 7 µg Cu L(-1). When these effects are compared to data available in the literature for other freshwater fish, also for 96 h of exposure, R. quelen appears as a relatively sensitive species. In addition, the concentrations employed here were quite low in comparison to levels used for disease control in real culture practices (ranging from 4 µg Cu L(-1) used against bacteria to 6000 µg Cu L(-1) against fungal infections). We can conclude that the concentrations frequently employed in aquaculture are in fact not safe enough for this species. Such data are essential for the questioning and establishment of new policies to the sector.


Assuntos
Peixes-Gato/fisiologia , Cobre/toxicidade , Água Doce , Fígado/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Citocromo P-450 CYP1A1/metabolismo , Ativação Enzimática/efeitos dos fármacos , Enzimas/metabolismo , Pesqueiros , Brânquias/efeitos dos fármacos , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos
8.
J Environ Monit ; 14(8): 2154-63, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22772567

RESUMO

Few studies have investigated the bioaccumulation of persistent organic pollutants (POPs) in Brazilian native freshwater fish. In order to evaluate the bioavailability, potential risk to human exposure and the effects of POPs in the fish Hypostomus commersoni, muscle and liver samples of thirteen specimens were collected in a lake located in the city of Ponta Grossa (Parana State, Southern Brazil). Also, the liver and gills were considered for histopathological studies, and oxidative stress was investigated in the liver. Expressive concentrations of POPs were observed in the liver and muscle, with a total of 427 ± 78.7 and 69.2 ± 18.1 ng g(-1) dry weights of polychlorinated biphenyls (PCBs), respectively. Negative correlations between the concentration of several POPs and glutathione S-transferase and glucose-6-phosphate dehydrogenase were found. Otherwise, the cholinesterase activity in the muscle and brain presented positive correlations with the concentration of POPs. The hepatic bioaccumulation of some banned pesticides like aldrin, dieldrin and DDT was associated with various histopathological findings in the liver and gills. Necrotic areas, fibrosis, leukocyte infiltration, and the absence of macrophage centers were observed in the liver, indicating both chronic exposure and immunological suppression. Neoplasic changes were observed in the gills, confirming the carcinogenic potential reported for some of the investigated pollutants. The current work was the first to study the bioaccumulation of POPs in H. commersoni, an important species in ecological aspects and as a vehicle to human exposure to PCBs and organochlorine pesticides (OCPs).


Assuntos
Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Biomarcadores/metabolismo , Brasil , Monitoramento Ambiental , Peixes , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Hidrocarbonetos Clorados/metabolismo , Hidrocarbonetos Clorados/toxicidade , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Músculos/efeitos dos fármacos , Músculos/metabolismo , Músculos/patologia , Praguicidas/toxicidade , Bifenilos Policlorados/toxicidade , Poluentes Químicos da Água/toxicidade
9.
Eur J Surg Oncol ; 34(7): 811-6, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17981427

RESUMO

While combined treatment of high-grade soft tissue sarcoma with resection and radiotherapy has become an accepted standard, outlines of treatment algorithms remain a matter of debate. Our institutional practice foresees wide surgical resection with adjuvant brachytherapy and external beam radiation. It was the purpose of this study to determine long-term outcome, prognostic factors for local and systemic recurrence and morbidity in patients with high-grade soft tissue sarcomas of the extremities, who were subjected to this regimen. One hundred and twelve patients met the inclusion criteria (56 male, 56 female; median age, 50 years). Median follow-up was 75 months (min. 11 months). Overall survival rate was 77.5% and 71.1% at 5 and 7 years, respectively. Disease-free survival rate was 63.3% and 58.4% at 5 and 10 years, respectively. Local control was achieved in 91.5% and 87.0% at 5 and 10 years, respectively. Wide surgical margins were associated with a significantly better local control rate compared to marginal or intralesional margins. Tumor size did correlate with systemic but not local recurrence. Tumor site and histotype did not appear to have an impact on outcome. Chemotherapy did not show to have an impact on local or systemic control. Fourteen patients (12.5%) had local complications attributed to radiotherapy. Eleven patients developed wound-healing problems, which needed further surgery. Using our treatment algorithm for high-grade soft tissue sarcoma of the extremities, good local and systemic control can be achieved with a low complication rate.


Assuntos
Braquiterapia/métodos , Salvamento de Membro , Sarcoma/radioterapia , Sarcoma/cirurgia , Adolescente , Adulto , Idoso , Algoritmos , Braquiterapia/efeitos adversos , Criança , Extremidades , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/terapia , Prognóstico , Radioterapia Adjuvante , Fatores de Risco , Sarcoma/patologia , Análise de Sobrevida
10.
Liver Int ; 27(5): 646-53, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17498250

RESUMO

BACKGROUND: Transjugular liver biopsy (TJLB) can be performed to obtain more than two cores safely. This advantage has not been evaluated in terms of diagnostic accuracy or grading/staging evaluation. AIM: To evaluate whether three separate cores of TJLB provide more histological information compared with two or one cores. METHODS: Twenty-three patients, who had three separate passes, with each core >/=7mm in length using a 19G Tru-cut needle, were evaluated. Each TJLB was blindly coded; the pathologist randomly assessed: (a) each core separately covering the other two, (b) two cores simultaneously covering the third and (c) the three cores together for diagnostic yield, inflammation and fibrosis. RESULTS: The mean TJLB length was 32+/-5.5mm. In 12 one-core (52%) and 18 2-core (78%) assessments, diagnosis (mainly cirrhosis) was made correctly in each core. The within-patient standard deviations for one-core vs two-core assessment were similar for grading (0.42 and 0.47, respectively), but higher for staging (0.39 and 0.15, respectively). Staging was underestimated in assessing one-core and less for two cores compared to three cores. CONCLUSION: Three non-fragmented cores (each core >/=7mm in length) of TJLB can be considered a minimum requirement for histological assessment, giving better reproducibility in diagnosis as well as for inflammation and fibrosis.


Assuntos
Biópsia/métodos , Hepatopatias/patologia , Fígado/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Intervencionista , Reprodutibilidade dos Testes
11.
Ecotoxicol Environ Saf ; 68(3): 426-35, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17296226

RESUMO

Methylmercury is a potent toxic present in Amazonian fish species due to gold mining activities. In the present work, we investigated the morphological effects of methylmercury in liver and kidney of Hoplias malabaricus feeding contaminated prey fish over 70 days. Two groups of nine mature fish (tested and control) were acclimatized for four weeks to laboratory conditions and then the tested group fed prey fish previously contaminated at an additional level of 0.075 microg MeHg g(-1) at 5-day intervals and over 14 successive intervals whereas control group fed uncontaminated fish. H. malabaricus specimens were then dissected for chemical and morphological analyses. The low and realistic level of MeHg in the prey fish induced a low increase of total mercury in liver (1.8-fold) and muscle (2.2-fold). The biomagnification factor (Hg in predator/Hg in prey) reached 142 in liver and 21 in muscle and was indicative of a relatively fast contamination of internal organs by dietary exposure. The liver of exposed individuals presented leukocyte infiltration, increased number of melano-macrophage centers, necrotic areas and lesions in Disse's space. Evident disorder and chaos in cytoskeleton organization suggest a strong toxic effect in hepatocytes, such as organelles positioning and movement, vesicles traffic and secretion. Head kidney showed large necrosis areas, increased number of melano-macrophages centers, phagocytic areas, intercellular space among parenquimal cells and atypical cells. Injuries and damages to tissues suggest too slow defense mechanisms to immobilize or eliminate ingested methylmercury, demonstrating that the sensitivity of fish cells to methylmercury exposure is higher than it has been previously described in the literature.


Assuntos
Peixes , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Brasil , Dieta , Cadeia Alimentar , Contaminação de Alimentos , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Compostos de Metilmercúrio/administração & dosagem , Compostos de Metilmercúrio/metabolismo , Fatores de Tempo , Clima Tropical , Poluentes Químicos da Água/administração & dosagem , Poluentes Químicos da Água/metabolismo
12.
Eur J Surg Oncol ; 33(4): 512-7, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17174515

RESUMO

BACKGROUND: Limb salvage surgery of popliteal soft tissue sarcomas may be hampered due to the incomplete anatomical containment of this region and the vicinity of neurovascular structures. The scope of this study was to determine outcome and to define risk factors. PATIENTS AND METHODS: 27 patients (53.3+/-15.8 y; 16/27 male) with popliteal soft tissue sarcomas were assessed. Mean follow-up was 40.9+/-33.8 months (48.5+/-36.7 months in surviving patients). 9/27 patients were included after prior treatment elsewhere (5 after intralesional resections and 4 local recurrences). The lesions were staged IB in 8/27 patients, IIB in 17/27 and III in 2/27. Immediate amputations were performed in 7/27 patients. 15/27 patients were subjected to radiation therapy (preoperative in 6/15 cases), 8/27 patients received chemotherapy (5/8 preoperatively). RESULTS: Overall survival and disease-free survival at 5 y was 63.0% and 59.5%. Local recurrence occurred in 2 patients. 8/27 patients developed metastatic disease after 28.9+/-9.8 months. Survival (p=0.397) and disease-free survival (p=0.113) did not differ in patients after amputations vs limb salvage. Application of radiation therapy was associated with a better survival (p=0.003). Complications related to the surgical intervention were recorded in 2/27 patients, complications related to radiation therapy occurred in 6/15 patients. DISCUSSION: Despite being extra-compartmental, popliteal sarcomas can be treated with a high rate of limb salvage while equal safety compared to amputations is maintained. Irradiation improved survival in our patient population. In cases with involvement of neurovascular structures, preoperative down-staging with radio or chemo-therapy may prevent amputation.


Assuntos
Perna (Membro) , Salvamento de Membro/métodos , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Adulto , Idoso , Amputação Cirúrgica , Quimioterapia Adjuvante , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radioterapia Adjuvante , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento
13.
Braz J Med Biol Res ; 39(7): 987-95, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16862290

RESUMO

Methyl mercury (MeHg) is highly neurotoxic, affecting visual function in addition to other central nervous system functions. The effect of mercury intoxication on the amplitude of horizontal cell responses to light was studied in the retina of the fish Hoplias malabaricus. Intracellular responses were recorded from horizontal cells of fish previously intoxicated with MeHg by intraperitoneal injection (IP group) or by trophic exposure (T group). Only one retina per fish was used. The doses of MeHg chloride administered to the IP group were 0.01, 0.05, 0.1, 1.0, 2.0, and 6.0 mg/kg. The amplitudes of the horizontal cell responses were lower than control in individuals exposed to 0.01 (N = 4 retinas), 0.05 (N = 2 retinas) and 0.1 mg/kg (N = 1 retina), whereas no responses were recorded in the 1.0, 2.0, and 6.0 mg/kg groups. T group individuals were fed young specimens of Astyanax sp previously injected with MeHg corresponding to 0.75 (N = 1 retina), 0.075 (N = 8 retinas) or 0.0075 (N = 4 retinas) mg/kg fish body weight. After 14 doses, one every 5 days, the amplitude of the horizontal cell response was higher than control in individuals exposed to 0.075 and 0.0075 mg/kg, and lower in individuals exposed to 0.75 mg/kg. We conclude that intoxication with MeHg affects the electrophysiological response of the horizontal cells in the retina, either reducing or increasing its amplitude compared to control, and that these effects are related to the dose and/or to the mode of administration.


Assuntos
Peixes , Compostos de Metilmercúrio/toxicidade , Células Horizontais da Retina/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Eletrofisiologia , Compostos de Metilmercúrio/administração & dosagem , Células Horizontais da Retina/fisiologia
14.
Braz. j. med. biol. res ; 39(7): 987-995, July 2006. ilus
Artigo em Inglês | LILACS | ID: lil-431556

RESUMO

Methyl mercury (MeHg) is highly neurotoxic, affecting visual function in addition to other central nervous system functions. The effect of mercury intoxication on the amplitude of horizontal cell responses to light was studied in the retina of the fish Hoplias malabaricus. Intracellular responses were recorded from horizontal cells of fish previously intoxicated with MeHg by intraperitoneal injection (IP group) or by trophic exposure (T group). Only one retina per fish was used. The doses of MeHg chloride administered to the IP group were 0.01, 0.05, 0.1, 1.0, 2.0, and 6.0 mg/kg. The amplitudes of the horizontal cell responses were lower than control in individuals exposed to 0.01 (N = 4 retinas), 0.05 (N = 2 retinas) and 0.1 mg/kg (N = 1 retina), whereas no responses were recorded in the 1.0, 2.0, and 6.0 mg/kg groups. T group individuals were fed young specimens of Astyanax sp previously injected with MeHg corresponding to 0.75 (N = 1 retina), 0.075 (N = 8 retinas) or 0.0075 (N = 4 retinas) mg/kg fish body weight. After 14 doses, one every 5 days, the amplitude of the horizontal cell response was higher than control in individuals exposed to 0.075 and 0.0075 mg/kg, and lower in individuals exposed to 0.75 mg/kg. We conclude that intoxication with MeHg affects the electrophysiological response of the horizontal cells in the retina, either reducing or increasing its amplitude compared to control, and that these effects are related to the dose and/or to the mode of administration.


Assuntos
Animais , Peixes , Compostos de Metilmercúrio/toxicidade , Células Horizontais da Retina/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eletrofisiologia , Compostos de Metilmercúrio/administração & dosagem , Células Horizontais da Retina/fisiologia
15.
Transpl Infect Dis ; 8(1): 3-12, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16623815

RESUMO

BACKGROUND: Reducing immunosuppression not only reduces complications but also may lessen recurrent hepatitis C virus (HCV) infection after liver transplantation. PATIENTS/METHODS: HCV-infected cirrhotic patients randomised to tacrolimus monotherapy (MT) or triple therapy (TT) using tacrolimus 0.1 mg/kg/day, azathioprine 1 mg/kg/day, and prednisolone 20 mg/day, tapering over 3 months. RESULTS: Twenty-seven patients (MT) and 29 (TT)--median follow up 661 days (range, 1-1603). Rejection episodes (protocol/further biopsies) within first 3 months and use of empirical treatment were evaluated. New rejection was diagnosed if repeat biopsy (5-day interval) did not show improvement. Treated rejection episodes: 20 MT (15 biopsy-proven) vs. 24 TT (21 biopsy-proven), with 19 (MT) vs. 24 (TT) methylprednisolone boluses. Overall: 35 episodes (MT) and 46 (TT). Fewer MT patients had histological rejection (70%) than TT patients (86%), with fewer episodes of rejection (18.5% vs. 10%), and more moderate rejection (22% vs. 41%). The MT group had higher early tacrolimus levels. Rates of renal dysfunction, retransplantation, and death were not significantly different. CONCLUSION: Tacrolimus monotherapy is a viable immunosuppressive strategy in HCV-infected liver transplant recipients.


Assuntos
Rejeição de Enxerto/prevenção & controle , Hepatite C/terapia , Imunossupressores/uso terapêutico , Cirrose Hepática/terapia , Transplante de Fígado , Tacrolimo/uso terapêutico , Adulto , Idoso , Azatioprina/uso terapêutico , Quimioterapia Combinada , Feminino , Hepatite C/complicações , Humanos , Cirrose Hepática/virologia , Transplante de Fígado/imunologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Prednisolona/uso terapêutico , Prevenção Secundária , Análise de Sobrevida , Fatores de Tempo , Transplante Homólogo , Resultado do Tratamento
16.
Environ Res ; 101(1): 74-80, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16388797

RESUMO

Hematological indices are gaining general acceptance as valuable tools in monitoring various aspects the health of fish exposed to contaminants. In this work some effects of methyl mercury (MeHg), inorganic lead (Pb2+), and tributyltin (TBT) in a tropical fish species were evaluated by hematological methods after a trophic exposition at a subchronic level. Forty-two mature individuals of the freshwater top predator fish Hoplias malabaricus were exposed to trophic doses (each 5 days) of MeHg (0.075 microg g(-1)), Pb2+ (21 microg g(-1)), and TBT (0.3 microg g(-1)) using young fish Astyanax sp. as prey vehicle. After 14 successive doses over 70 days, blood was sampled from exposed and control groups to evaluate hematological effects of metals on erythrocytes, total leukocytes and differential leukocytes counts, hematocrit, hemoglobin concentration, and red blood cell indices mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC). Transmission electron microscopy and image analysis of erythrocytes were also used to investigate some morphometric parameters. Results show no significant effects in MCH and MCHC for all tested metals, but differences were found in erythrocytes, hemoglobin, hematocrit, MCV, and white blood cells counts. The number of leukocytes was increased in the presence of MeHg, suggesting effects on the immune system. Also the MCV increased in individuals exposed to MeHg. No ultrastructural damages were observed in red blood cells but the image analysis using light microscopy revealed differences in area, elongation, and roundness of erythrocytes from individuals exposed to Pb2+ and TBT but not in the group exposed to MeHg. The present work shows that changes in hematological and blood indices could highlight some barely detectable metal effects in fish after laboratory exposure to contaminated food, but their application in field biomonitoring using H. malabaricus will need more detailed studies and a careful consideration of environmental parameters.


Assuntos
Peixes/fisiologia , Chumbo/toxicidade , Compostos de Metilmercúrio/toxicidade , Compostos de Trialquitina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Dieta , Índices de Eritrócitos/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eritrócitos/fisiologia , Eritrócitos/ultraestrutura , Cadeia Alimentar , Hematócrito , Contagem de Leucócitos , Microscopia Eletrônica de Transmissão , Clima Tropical
17.
Eur J Surg Oncol ; 30(5): 565-72, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15135488

RESUMO

AIMS: Soft tissue leiomyosarcomas (LMS) are rare tumours which are associated with a poor prognosis. The goals of the present study were to describe the clinico-pathological and prognostic features of 42 patients affected by soft tissue LMS of the extremities. METHODS: The following clinical and pathological parameters were analysed: age, sex, site, size, depth, previous surgical procedures, stage, histological type, nuclear atypia, grade, mitotic activity, necrosis, surgical margins, therapy. Disease-free survival rates were calculated. RESULTS: The overall 2-year and 5-year disease free survival rates were 42.3% and 32.6%, respectively. By univariate analysis, tumour size (< or =10 cm vs. >10 cm; p = 0.01), average mitotic rate (< or =19/10 HPF vs. >19/10 HPF; p = 0.05), type of excision (wide vs. marginal or intralesional; p = 0.001) and adjuvant radiotherapy (none vs. brachytherapy+external beam radiotherapy vs. external beam radiotherapy; p = 0.02) were significantly correlated with disease progression. By multivariate analysis, the only factor that was found to be an independent predictor of disease relapse was type of excision (p = 0.001). CONCLUSIONS: Large tumour size and high mitotic rate resulted adverse prognostic factors. Adjuvant radiation therapy, in combination with wide surgical excision, allowed the best chance of cure.


Assuntos
Extremidades/patologia , Leiomiossarcoma/diagnóstico , Neoplasias de Tecidos Moles/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia , Progressão da Doença , Intervalo Livre de Doença , Extremidades/efeitos da radiação , Feminino , Seguimentos , Histiocitoma Fibroso Benigno/diagnóstico , Histiocitoma Fibroso Benigno/mortalidade , Histiocitoma Fibroso Benigno/terapia , Humanos , Itália/epidemiologia , Leiomiossarcoma/mortalidade , Leiomiossarcoma/terapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/etiologia , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Estudos Retrospectivos , Sarcoma/diagnóstico , Sarcoma/mortalidade , Sarcoma/terapia , Neoplasias de Tecidos Moles/mortalidade , Neoplasias de Tecidos Moles/terapia , Procedimentos Cirúrgicos Operatórios
18.
Gut ; 53(1): 143-8, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14684589

RESUMO

Recurrent variceal bleeding is very frequent after variceal haemorrhage and pharmacological therapy is the first choice treatment. Recently, baseline and repeat measurements of hepatic venous pressure gradient (HVPG) have been considered necessary to optimally manage patients receiving pharmacological therapy so as to reduce the frequency of rebleeding. However, the clinical validity and applicability of monitoring for target HVPG reductions is not sufficiently proven and needs to be specifically evaluated in a prospective trial.


Assuntos
Anti-Hipertensivos/uso terapêutico , Monitoramento de Medicamentos/métodos , Varizes Esofágicas e Gástricas/prevenção & controle , Hemorragia Gastrointestinal/prevenção & controle , Hipertensão Portal/tratamento farmacológico , Medicina Baseada em Evidências , Humanos , Hipertensão Portal/fisiopatologia , Pressão na Veia Porta/efeitos dos fármacos
19.
J Endocrinol Invest ; 26(7): 623-8, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14594112

RESUMO

Growth was monitored in 133 male and 150 female North Sardinian prepubertal patients with homozygous beta-thalassemia in order to ascertain the incidence of GH deficiency (GHD) and the effects of long-term recombinant GH (recGH) treatment on growth velocity and bone maturation. A significant reduction in growth velocity and a fall in IGF-I levels was observed in 19 male and 16 female patients (12.3%). Their peak GH responses to GHRH (5.45+/-0.78 and 4.99+/-0.86 ng/ml) and clonidine administration (4.21+/-0.32 and 4.15+/-0.27 ng/ml in males and females, respectively) were markedly reduced with respect to control subjects (p<0.01). No statistically significant correlation was found between chronological age, number of blood units received, plasma ferritin levels and plasma IGF-I levels as well as with peak GH response to stimulation. Thalassemic patients with GHD had plasma ferritin levels (1382.44+/-160.34 and 1255.23+/-139.81 ng/ml in males and females, respectively) significantly lower than those recorded in the other patients (2848.94+/-283.61 and 3077.82+/-220.51 ng/ml). Patients with GHD were treated with recGH for an average period of 59 months (range 26-124). Treatment was able to restore growth and to increase significantly plasma IGF-I levels. Growth velocity at the end of the first yr of treatment was 6.78+/-1.21 and 6.11+/-0.85 cm/yr in males and females, respectively. Growth velocity values and plasma IGF-I levels remained significantly higher than basal values throughout the period of treatment. However, treatment was unable to normalize bone maturation since bone age values were always reduced with respect to chronological age. No incidence of side effects was observed. These data indicate that GHD, when present, is one but not the sole cause of delayed bone maturation and height deficiency in thalassemia.


Assuntos
Transfusão de Sangue , Hormônio do Crescimento/uso terapêutico , Hormônio do Crescimento Humano/metabolismo , Talassemia beta/metabolismo , Talassemia beta/terapia , Adolescente , Agonistas alfa-Adrenérgicos/farmacologia , Determinação da Idade pelo Esqueleto , Desenvolvimento Ósseo/efeitos dos fármacos , Criança , Pré-Escolar , Clonidina/farmacologia , Feminino , Ferritinas/sangue , Crescimento/efeitos dos fármacos , Homozigoto , Hormônio do Crescimento Humano/deficiência , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Assistência de Longa Duração , Masculino , Talassemia beta/genética
20.
Aliment Pharmacol Ther ; 17 Suppl 2: 130-7, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12786624

RESUMO

The role of liver transplantation for hepatocellular carcinoma has evolved over the years and currently is one of the curative therapies for small tumours. The survival rates are similar with those for nonmalignant liver disease after transplantation. The treatment of small tumours eligible for both resection and transplantation depends on the experience of the transplant centre and the waiting time for a liver graft. With waiting times for liver transplant becoming gradually longer, prioritization of the tumour patients has been suggested. Adjuvant therapies may delay the tumour progression while patients wait for a transplant. The living donor and the domino liver transplantation are useful alternatives given the shortage of organs but the experience is still limited in the Western world and the selection for the domino livers is fairly restricted.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/métodos , Carcinoma Hepatocelular/diagnóstico , Terapia Combinada/métodos , Humanos , Neoplasias Hepáticas/diagnóstico , Estadiamento de Neoplasias/métodos , Seleção de Pacientes , Prognóstico , Listas de Espera
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