Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
1.
Exp Oncol ; 45(1): 107-119, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37417276

RESUMO

BACKGROUND: Skeletal muscle wasting is a common phenotypic feature of several types of cancer, and it is associated with functional impairment, respiratory complications, and fatigue. However, equivocal evidence remains regarding the impact of cancer-induced muscle wasting on the different fiber types. AIM: The aim of this study was to investigate the impact of urothelial carcinoma induced in mice on the histomorphometric features and collagen deposition in different skeletal muscles. MATERIALS AND METHODS: Thirteen ICR (CD1) male mice were randomly assigned into two groups: exposed to 0.05% N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in drinking water for 12 weeks, plus 8 weeks of tap water (BBN, n = 8) or with access to tap water for 20 weeks (CONT, n = 5). Tibialis anterior, soleus, and diaphragm muscles were collected from all animals. For cross-sectional area and myonuclear domain analysis, muscle sections were stained with hematoxylin and eosin, and for collagen deposition assessment, muscle sections were stained with picrosirius red. RESULTS: All animals from the BBN group developed urothelial preneoplastic and neoplastic lesions, and the tibialis anterior from these animals presented a reduced cross-sectional area (p < 0.001), with a decreased proportion of fibers with a higher cross-sectional area, increased collagen deposition (p = 0.017), and higher myonuclear domain (p = 0.031). BBN mice also showed a higher myonuclear domain in the diaphragm (p = 0.015). CONCLUSION: Urothelial carcinoma induced muscle wasting of the tibialis anterior, expressed by a decreased cross-sectional area, higher infiltration of fibrotic tissue, and increased myonuclear domain, which also increased in the diaphragm, suggesting that fast glycolytic muscle fibers are more susceptible to be affected by cancer development.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Camundongos , Masculino , Animais , Carcinoma de Células de Transição/patologia , Neoplasias da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/patologia , Camundongos Endogâmicos ICR , Músculo Esquelético/patologia , Músculo Esquelético/fisiologia , Fibras Musculares de Contração Rápida/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/patologia
2.
Arq. bras. med. vet. zootec. (Online) ; 73(6): 1294-1300, Nov.-Dec. 2021. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355682

RESUMO

Brucella ovis, a non-zoonotic species, is the etiological agent of ovine brucellosis, an infectious disease of clinical or subclinical occurrence in sheep flocks. Until then, there is no serological study of anti-Brucella ovis antibodies in purebred sheep herds. This study aimed to determine the presence of anti-Brucella ovis antibodies in purebred sheep flocks with breeding purposes from Parana State. Blood samples from 728 animals, of which 563 were females and 165 males, between 8 and 56 months of age from the six major sheep producing mesoregions of Parana, were submitted to detection of anti-Brucella ovis antibodies by the Agar Gel Immunodiffusion technique using an antigen from the bacteria Brucella ovis (Reo 198). The results indicate the presence of this disease in purebred sheep from Parana State in a low occurrence of 0.27% (2/728). The only two positive animals were rams, Santa Inês breed, from the same flock in the East Center region of Parana, without clinical disease. In conclusion, Brucella ovis is present in purebred sheep in Parana State, Brazil, and this low occurrence may have occurred due to rigorous breeding systems that may contribute to reduce the transmission of this disease.(AU)


Brucella ovis, espécie não zoonótica, é o agente etiológico da brucelose ovina, doença infecciosa de ocorrência clínica ou subclínica. Atualmente, não existe estudo sorológico de anticorpos anti-Brucella ovis em rebanhos de ovinos puros de origem. Este estudo teve como objetivo determinar a presença de anticorpos anti-Brucella ovis em rebanhos ovinos de raça pura de origem, com fins reprodutivos do estado do Paraná. Amostras de sangue de 728 animais, sendo 563 fêmeas e 165 machos, entre oito e 56 meses de idade, pertencentes a seis principais mesorregiões produtoras de ovinos no Paraná, foram submetidas à detecção de anticorpos anti-Brucella ovis pela técnica de imunodifusão em ágar gel usando-se um antígeno da bactéria Brucella ovis (Reo 198). Os resultados indicam a presença da doença em ovinos puros de origem do estado do Paraná em baixa ocorrência de 0,27% (2/728). Os dois únicos animais positivos foram reprodutores da raça Santa Inês, do mesmo rebanho da região Centro Leste do Paraná, sem manifestação clínica. Em conclusão, Brucella ovis está presente em ovinos puros de origem no estado do Paraná, e essa baixa ocorrência pode ter ocorrido devido a sistemas rigorosos de criação, que podem contribuir para a redução da transmissão dessa doença.(AU)


Assuntos
Animais , Brucelose/epidemiologia , Ovinos/imunologia , Brucella ovis/imunologia , Doenças dos Ovinos/imunologia , Brasil , Imunodifusão/veterinária
3.
Food Funct ; 12(6): 2631-2643, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33645604

RESUMO

Prostate cancer (PCa) is one of the most common cancers in men, with a huge impact on their health. The use of Castanea sativa Mill. flowers (CFs) in beverages has been reported, through ancestral claims, as having health benefits. In vitro research has evidenced the properties of CFs, such as antitumor and antioxidant activities. This study aimed to evaluate the effects of CF extract in an animal model of PCa. Forty male Wistar Unilever rats were randomly assigned to four groups: control, induced, control + CF, and induced + CF groups. Animals from the induced groups were exposed to a multistep protocol for PCa induction. The CF extract, rich in trigalloyl-HHDP-glucoside and obtained via decoction, was administered to the CF groups in drinking water (3 mg per animal per day) for 49 weeks. Animals were sacrificed at 61 weeks of age. Regarding the effects of CFs on dorsolateral prostate tumorigenesis, no significant differences were observed between the induced and induced + CF groups. However, animals exposed to the CF extract showed fewer inflammation areas on the dorsolateral prostate lobe than those not exposed to CF. Moreover, the CF extract alleviated the hepatic oxidative stress associated with the multistep protocol, resulting in lower levels of lipid peroxidation. These results suggest that CF extract has antioxidant and anti-inflammatory properties.


Assuntos
Antineoplásicos/farmacologia , Fagaceae/química , Flores/química , Extratos Vegetais/farmacologia , Neoplasias da Próstata/metabolismo , Animais , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Neoplasias Experimentais , Estresse Oxidativo/efeitos dos fármacos , Próstata/efeitos dos fármacos , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/patologia , Ratos , Ratos Wistar
4.
Biochim Biophys Acta Rev Cancer ; 1874(2): 188438, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32980466

RESUMO

The increasing incidence of skin cancer (SC) is a global health concern. The commonly reported side effects and resistance mechanisms have imposed the pursuit for new therapeutic alternatives. Moreover, additional preventive strategies should be adopted to strengthen prevention and reduce the rising number of newly SC cases. This review provides relevant insights on the role of p53 tumour suppressor protein in melanoma and non-melanoma skin carcinogenesis, also highlighting the therapeutic potential of p53-targeting drugs against SC. In fact, several evidences are provided demonstrating the encouraging outcomes achieved with p53-activating drugs, alone and in combination with currently available therapies in SC. Another pertinent perspective falls on targeting p53 mutations, as molecular signatures in premature phases of photocarcinogenesis, in future SC preventive approaches. Overall, this review affords a critical and timely discussion of relevant issues related to SC prevention and therapy. Importantly, it paves the way to future studies that may boost the clinical translation of p53-activating agents, making them new effective alternatives in precision medicine of SC therapy and prevention.


Assuntos
Melanoma/metabolismo , Neoplasias Cutâneas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Terapia de Alvo Molecular , Mutação , Transdução de Sinais/efeitos dos fármacos , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética
5.
Med Hypotheses ; 144: 109979, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32570162

RESUMO

Atheromatous plaques occurring in large arteries are common and life-threatening lesions. Multiple factors are involved in the pathogenesis of atheromatous plaques, such as hyperlipidaemia and hypercholesterolaemia, high blood pressure and chronic systemic inflammation. Recent findings have suggested that infection with high-risk human papillomavirus (HPV) may increase the risk of developing atheromatous plaques. However, HPV is considered a tissue-specific virus with a strong tropism towards squamous epithelial cells, and the mechanisms whereby it may promote the development of atheromas remain unclear. Here, we propose a connecting hypothesis to explain the possible causative role of HPV on atheroma development. We hypothesize that HPV infection may promote atheroma formation in infected patients by enhancing systemic inflammation or by directly targeting blood vessels via nucleic acids carried by extracellular vesicles such as exosomes. The pro-inflammatory effects of HPV and the release of extracellular vesicles by HPV-transformed cells are well documented in scientific literature. Possible experimental approaches to test this hypothesis are also discussed, especially experiments employing transgenic mice bearing HPV16 transgenes. If correct, this hypothesis would have major implications for the prevention of cardiovascular diseases, especially due to the preventable nature of HPV infection through vaccination.


Assuntos
Aterosclerose , Infecções por Papillomavirus , Animais , Papillomavirus Humano 16 , Humanos , Camundongos , Camundongos Transgênicos , Infecções por Papillomavirus/complicações , Fatores de Risco
7.
Food Funct ; 9(8): 4419-4428, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30066000

RESUMO

Cancers induced by human papillomavirus (HPV) infection remain a significant public health threat, fueling the study of new therapies. Laurel (Laurus nobilis) compounds and extracts recently showed in vitro activity against HPV-transformed cell lines. This work aims to evaluate the in vivo efficacy and hepatic toxicity of a laurel extract in a transgenic mouse model of HPV16-induced cancer. The extract was administered in drinking water (20 mg per animal per day) for three consecutive weeks, using four experimental groups (n = 10) (group I: HPV16-/- without treatment, group II: treated HPV16-/-, group III: HPV16+/- without treatment and group IV: treated HPV16+/-). Following the treatment period, animals were sacrificed and skin samples were used to classify skin lesions histologically. Toxicological parameters included hematological and biochemical blood markers, splenic and hepatic histology and hepatic oxidative stress. The extract did not prevent the progression of HPV16-induced cutaneous lesions in this model. The treated wild-type animals showed mild hepatitis, while transgenic animals suffered weight loss. However, there were no changes concerning hematological, biochemical and hepatic oxidative stress markers.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Papillomavirus Humano 16/fisiologia , Laurus/química , Infecções por Papillomavirus/virologia , Extratos Vegetais/toxicidade , Neoplasias do Colo do Útero/virologia , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Feminino , Papillomavirus Humano 16/genética , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Transgênicos , Estresse Oxidativo/efeitos dos fármacos , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
8.
Biomed Pharmacother ; 104: 275-279, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29775895

RESUMO

Infection with high-risk human papillomavirus (HPV), most often HPV16, is associated with the development of anogenital and oropharyngeal cancers. Recently, ozone therapy was reported to have considerable efficacy against rabbit VX2 tumors, induced by the cottontail rabbit papillomavirus. The present study aims to determine whether similar results can be obtained in HPV16-transgenic mice, possibly paving the way for new therapeutic options against HPV-induced cancers. HPV16-transgenic and wild-type, female, 20 weeks-old mice were injected intraperitoneally with medical O3/O2 (80░mL/kg, at O3 50░µg/mL), once a day, for 5 consecutive days. The animals were sacrificed at 25 weeks-old, and skin samples were analyzed histologically to study tumour progression. Blood and internal organ samples were used to study toxicological parameters. 85.7% of untreated transgenic mice showed dysplastic skin lesions, compared with 28.6% of O3-treated mice. This was associated with a marked reduction of dermal inflammation associated with those lesions. No significant changes were observed in any toxicological parameters. These preliminary results support the hypothesis that O3 therapy is effective against papillomavirus-induced lesions, particularly against those induced by the most common high-risk virus, HPV16. Further studies are needed to confirm the mechanisms underlying these effects.


Assuntos
Papillomavirus Humano 16/patogenicidade , Neoplasias/tratamento farmacológico , Ozônio/farmacologia , Dermatopatias/tratamento farmacológico , Animais , Progressão da Doença , Feminino , Camundongos , Camundongos Transgênicos , Neoplasias/virologia , Infecções por Papillomavirus/complicações , Coelhos , Pele/efeitos dos fármacos , Pele/virologia , Dermatopatias/virologia , Resultado do Tratamento
9.
Acta Physiol (Oxf) ; 219(4): 803-813, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27228549

RESUMO

AIM: Exercise training has been suggested as a non-pharmacological approach to prevent skeletal muscle wasting and improve muscle function in cancer cachexia. However, little is known about the molecular mechanisms underlying such beneficial effect. In this study, we aimed to, firstly, examine the contribution of TWEAK signalling to cancer-induced skeletal muscle wasting and, secondly, evaluate whether long-term exercise alters TWEAK signalling and prevents muscle wasting. METHODS: Female Sprague-Dawley rats were randomly assigned to control and exercise groups. Fifteen animals from each group were exposed to N-Methyl-N-nitrosourea carcinogen. Animals in exercise groups were submitted to moderate treadmill exercise for 35 weeks. After the experimental period, animals were killed and gastrocnemius muscles were harvested for morphological and biochemical analysis. RESULTS: We verified that exercise training prevented tumour-induced TWEAK/NF-κB signalling in skeletal muscle with a beneficial impact in fibre cross-sectional area and metabolism. Indeed, 35 weeks of exercise training promoted the upregulation of PGC-1α and oxidative phosphorylation complexes. This exercise-induced muscle remodelling in tumour-bearing animals was associated with less malignant mammary lesions. CONCLUSION: Data support the benefits of an active lifestyle for the prevention of muscle wasting secondary to breast cancer, highlighting TWEAK/NF- κB signalling as a potential therapeutic target for the preservation of muscle mass.


Assuntos
Proteínas Reguladoras de Apoptose/biossíntese , Caquexia/metabolismo , Neoplasias Mamárias Experimentais/complicações , Proteínas de Membrana/biossíntese , Condicionamento Físico Animal/métodos , Transdução de Sinais , Fatores de Necrose Tumoral/biossíntese , Animais , Caquexia/etiologia , Citocina TWEAK , Modelos Animais de Doenças , Feminino , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo , NF-kappa B/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia
10.
J Anim Sci ; 94(11): 4720-4727, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27898972

RESUMO

This aim of this study was to evaluate the use of peanut cake as a dietary substitute for soybean meal and to determine the effects on intake, apparent digestibility, performance, and N metabolism in feedlot-finished young bulls. Thirty-two young Nellore bulls with an average initial BW of 390 ± 43.5 kg were distributed in a completely randomized design and individually housed in stalls. The young bulls were fed Tifton 85 hay and 4 concentrate mixes containing 0, 33, 66, or 100% peanut cake replacing soybean meal. The diets were formulated to be isonitrogenous, containing 150 g/kg CP, and isocaloric (65% TDN), to have a 40:60 forage:concentrate ratio, and were provided as a total mixed ration. The experiment lasted 90 d and data were collected every 28 d. Blood and urine samples were taken during the last 6 d. Intakes of DM ( = 0.005), OM ( = 0.006), CP ( = 0.002), NDF ( = 0.022), nonfiber carbohydrates ( = 0.002), and TDN ( = 0.018) linearly decreased as the dietary inclusion of peanut cake in the diet was increased. Conversely, intake and ether extract digestibility linearly increased ( < 0.035). The average daily weight gain decreased ( = 0.015) as the peanut cake levels were increased. Plasma urea N decreased (linearly; = 0.005). Peanut cake may not be used to replace soybean meal in the diet of young feedlot-finished Nellore bulls.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Ingestão de Alimentos , Nitrogênio/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Arachis , Nitrogênio da Ureia Sanguínea , Dieta/veterinária , Digestão , Comportamento Alimentar , Masculino , Distribuição Aleatória , Glycine max , Aumento de Peso
11.
Biomed Pharmacother ; 81: 273-280, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27261604

RESUMO

BACKGROUND: Breast cancer remains a leading cause of death by cancer worldwide. It is commonly accepted that angiogenesis and the expression of angiogenic factors such as vascular endothelial growth factor-A (VEGF-A) is associated with the increased risk of metastasis and poor patient outcome. OBJECTIVE: This work aimed to evaluate the effects of long-term exercise training on the growth and vascularization of mammary tumors in a rat model. MATERIALS AND METHODS: Fifty female Sprague-Dawley rats were divided into four groups: two N-methyl-N-nitrosourea (MNU)-exposed groups (exercised and sedentary) and two control groups (exercised and sedentary). MNU was administered once, intraperitoneally at 7 weeks-old. Animals were then exercised on a treadmill for 35 weeks. Mammary tumors were evaluated using thermography, ultrasonography [Power Doppler (PDI), B Flow and contrast-enhanced ultrasound (CEUS)], and immunohistochemistry (VEGF-A). RESULTS: Both, MNU sedentary and exercised groups showed 100% of tumor incidence, but exercised animals showed less tumors with an increased latency period. Exercise training also enhanced VEGF-A immunoexpression and vascularization (microvessel density, MVD) (p<0.05), and reduced histological aggressiveness. Ultrasound and thermal imaging analysis confirmed the enhanced vascularization of tumors on exercised animals. CONCLUSION: Long-term exercise training increased VEGF-A expression, leading to enhanced tumor vascularization and reduced tumor burden, multiplicity and histological aggressiveness.


Assuntos
Neoplasias Mamárias Experimentais/irrigação sanguínea , Neoplasias Mamárias Experimentais/fisiopatologia , Neovascularização Patológica/fisiopatologia , Condicionamento Físico Animal , Animais , Feminino , Imuno-Histoquímica , Neoplasias Mamárias Experimentais/diagnóstico por imagem , Neoplasias Mamárias Experimentais/patologia , Tamanho do Órgão , Ratos Sprague-Dawley , Termografia , Fatores de Tempo , Ultrassonografia , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
Tumour Biol ; 37(9): 11541-11551, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27235118

RESUMO

Despite the great scientific advances that have been made in cancer treatment, there is still much to do, particularly with regard to urinary bladder cancer. Some of the drugs used in urinary bladder cancer treatment have been in use for more than 30 years and show reduced effectiveness and high recurrence rates. There have been several attempts to find new and more effective drugs, to be used alone or in combination with the drugs already in use, in order to overcome this situation.The biologically important mammalian target of rapamycin (mTOR) pathway is altered in cancer and mTOR inhibitors have raised many expectations as potentially important anticancer drugs. In this article, the authors will review the mTOR pathway and present their experiences of the use of some mTOR inhibitors, sirolimus, everolimus and temsirolimus, in isolation and in conjunction with non-mTOR inhibitors cisplatin and gemcitabine, on urinary bladder tumour cell lines. The non-muscle-invasive cell line, 5637, is the only one that exhibits a small alteration in the mTOR and AKT phosphorylation after rapalogs exposure. Also, there was a small inhibition of cell proliferation. With gemcitabine plus everolimus or temsirolimus, the results were encouraging as a more effective response was noticed with both combinations, especially in the 5637 and T24 cell lines. Cisplatin associated with everolimus or temsirolimus also gave promising results, as an antiproliferative effect was observed when the drugs were associated, in particular on the 5637 and HT1376 cell lines. Everolimus or temsirolimus in conjunction with gemcitabine or cisplatin could have an important role to play in urinary bladder cancer treatment, depending on the tumour grading.


Assuntos
Serina-Treonina Quinases TOR/antagonistas & inibidores , Neoplasias da Bexiga Urinária/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/fisiologia
13.
Expert Opin Drug Discov ; 11(6): 599-607, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27077499

RESUMO

INTRODUCTION: Urinary bladder cancer (UBC) is the second most frequent malignancy of the urinary system and the ninth most common cancer worldwide, affecting individuals over the age of 65. Several investigations have embarked on advancing knowledge of the mechanisms underlying urothelial carcinogenesis, understanding the mechanisms of antineoplastic drugs resistance and discovering new antineoplastic drugs. In vitro and in vivo models are crucial for providing additional insights into the mechanisms of urothelial carcinogenesis. With these models, various molecular pathways involved in urothelial carcinogenesis have been discovered, allowing therapeutic manipulation. AREAS COVERED: This paper provides critical information on existing in vitro and in vivo models to screen the efficacy and toxicity of innovative UBC therapies and point out the challenges for new and improved models. EXPERT OPINION: In our opinion, results obtained with in vitro and in vivo models should be interpreted together, as a set of delicate biological tools that can be used at different stages in the drug discovery process, to address specific questions. With the development of new technologies, new assays and biomarkers are going to play an important role in the study of UBC. The molecular diagnostics and genomic revolution will not only help to develop new drug therapies, but also to achieve tailored therapies.


Assuntos
Antineoplásicos/uso terapêutico , Desenho de Fármacos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Idoso , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Descoberta de Drogas/métodos , Resistencia a Medicamentos Antineoplásicos , Humanos , Modelos Moleculares , Técnicas de Diagnóstico Molecular , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Urotélio/patologia
15.
Environ Toxicol ; 31(8): 1009-16, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25640707

RESUMO

Trihalomethanes (THMs) are disinfection byproducts found in chlorinated water, and are associated with several different kinds of cancer in human populations and experimental animal models. Metabolism of THMs proceeds through enzymes such as GSTT1 and CYP2E1 and gives rise to reactive intermediates, which form the basis for their toxic activities. The aim of this study was to assess the mitochondrial dysfunction caused by THMs at low levels, and the resulting hepatic histological and biochemical changes in the mouse. Male ICR mice were administered with two THMs: dibromochloromethane (DBCM) and bromodichloromethane (BDCM); once daily, by gavage, to a total of four administrations. Animals were sacrificed four weeks after DBCM and BDCM administrations. Blood biochemistry was performed for alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TB), albumin (Alb), total protein (TP), creatinine, and urea. Animals exposed to DBCM and BDCM showed elevated ALT and TB levels (p < 0.05) as compared with controls. Histological analysis confirmed the presence of vacuolar degenerescence and a multifocal necrotizing hepatitis in 33% of animals (n = 2). Mitochondrial analysis showed that THMs reduced mitochondrial bioenergetic activity (succinate dehydrogenase (SQR), cytochrome c oxidase (COX), and ATP synthase) and increased oxidative stress (glutathione S-transferase (GST)) in hepatic tissues (p < 0.05). These results add detail to the current understanding of the mechanisms underlying THM-induced toxicity, supporting the role of mitochondrial dysfunction and oxidative stress in liver toxicity caused by DBCM and BDCM. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1009-1016, 2016.


Assuntos
Estresse Oxidativo/efeitos dos fármacos , Trialometanos/toxicidade , Poluentes Químicos da Água/toxicidade , Alanina Transaminase/sangue , Animais , Doença Hepática Induzida por Substâncias e Drogas/sangue , Desinfecção , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Purificação da Água
17.
Med Phys ; 41(7): 072507, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24989410

RESUMO

PURPOSE: An original radionuclide calibrator method for activity determination is presented. The method could be used for intercomparison surveys for short half-life radioactive sources used in Nuclear Medicine, such as(99m)Tc or most positron emission tomography radiopharmaceuticals. METHODS: By evaluation of the resulting net optical density (netOD) using a standardized scanning method of irradiated Gafchromic XRQA2 film, a comparison of the netOD measurement with a previously determined calibration curve can be made and the difference between the tested radionuclide calibrator and a radionuclide calibrator used as reference device can be calculated. To estimate the total expected measurement uncertainties, a careful analysis of the methodology, for the case of(99m)Tc, was performed: reproducibility determination, scanning conditions, and possible fadeout effects. Since every factor of the activity measurement procedure can influence the final result, the method also evaluates correct syringe positioning inside the radionuclide calibrator. RESULTS: As an alternative to using a calibrated source sent to the surveyed site, which requires a relatively long half-life of the nuclide, or sending a portable calibrated radionuclide calibrator, the proposed method uses a source preparedin situ. An indirect activity determination is achieved by the irradiation of a radiochromic film using (99m)Tc under strictly controlled conditions, and cumulated activity calculation from the initial activity and total irradiation time. The irradiated Gafchromic film and the irradiator, without the source, can then be sent to a National Metrology Institute for evaluation of the results. CONCLUSIONS: The methodology described in this paper showed to have a good potential for accurate (3%) radionuclide calibrators intercomparison studies for(99m)Tc between Nuclear Medicine centers without source transfer and can easily be adapted to other short half-life radionuclides.


Assuntos
Calibragem , Radioisótopos/análise , Algoritmos , Desenho de Equipamento , Dosimetria Fotográfica , Meia-Vida , Tecnécio/análise , Incerteza
18.
Arq. bras. med. vet. zootec ; 66(3): 861-869, 06/2014. tab
Artigo em Português | LILACS | ID: lil-718063

RESUMO

Objetivou-se avaliar a substituição do farelo de soja por torta de amendoim no concentrado da dieta de novilhos, por meio do comportamento ingestivo e respostas fisiológicas. Foram utilizados cinco novilhos, dispostos em um quadrado latino 5 x 5. As dietas foram compostas de feno de tifton, milho moído, farelo de soja e torta de amendoim, constituídas de zero (100 por centode farelo de soja), 25, 50, 75 e 100 por cento de substituição por torta de amendoim no concentrado. Os níveis de torta de amendoim não influenciaram (P>0,05) as eficiências de ingestão e ruminação da matéria seca e da fibra em detergente neutro. Em relação às atividades comportamentais, o único parâmetro em que se observou efeito da substituição foi o número de períodos de ócio no turno da manhã (P<0,05), no qual se constatou efeito linear crescente. A taxa de secreção salivar e a quebra de partículas foram semelhantes, pois não houve efeito (P>0,05) das dietas sobre as características de mastigação. Como não houve efeito (P>0,05) das dietas sobre as frequências respiratória, cardíaca e a temperatura retal, o calor endógeno produzido pela fermentação ruminal foi equivalente. A torta de amendoim, por conter aflatoxinas, quando fornecida em alta relação volumoso x concentrado, pode substituir o farelo de soja na dieta de novilhos, pois ocasiona comportamento ingestivo e respostas fisiológicas semelhantes...


This study aimed to evaluate the replacement of soybean meal with peanut cake in the concentrate of steer diets through intake behavior and physiological responses. Five steers, arranged in a 5 x 5 latin square design were used. The diets were composed of Tifton hay, ground corn, soybean meal and peanut cake, made from zero (100 percent soybean meal), 25, 50, 75 and 100 percent replacement for peanut cake in the concentrate. The levels of peanut cake did not influence (P>0.05) the intake and rumination efficiencies of dry matter and fiber in neutral detergent. Regarding the behavioral activities, the only parameter that observed a substitution effect was the number of idle periods in the morning shift (P<0.05) which had an increasing linear effect. The rate of salivary secretion and the particle breakdown were similar, because there was no effect (P>0.05) of the diets on the chewing characteristics. As there was no effect (P>0.05) of the diets on the respiratory rate, heart rate and rectal temperature, the endogenous heat produced by rumen fermentation was equivalent. The peanut cake, by containing aflatoxin, when provided in high roughage x concentrate rate, can replace soybean meal in the steers' diet because it causes similar intake behavior and physiological responses...


Assuntos
Animais , Adolescente , Bovinos , Ração Animal , Arachis , Bovinos/fisiologia , Rúmen/fisiologia , Glycine max
19.
Neuroscience ; 271: 56-63, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24780767

RESUMO

The present study was aimed at analyzing the effects of physical exercise on mitochondrial physiology, anxio-depressive-like behaviors and neuroplasticity in mice. Adult C57BL/6J male mice were isolated in home cages equipped or not with free-running wheels. After 6weeks of exercise, mice were tested in various behavioral paradigms to evaluate anxiety- and depressive-like behaviors. The hippocampi were dissected for neurochemical assays, including mitochondrial activity, monoamines content and the expression of genes involved in energy metabolism and brain-derived neurotrophic factor (BDNF) regulation. Exercise decreased anxiety-like behaviors in the open field and elevated plus maze, and exerted antidepressant-like effects in the tail suspension test. Exercise stimulated brain mitochondrial activity and increased resistance against rotenone, an inhibitor of complex I activity. Furthermore, mRNA expression of Bdnf, Gdnf, Tfam (mitochondrial transcription factor A), and Ndufa6 (mitochondrial I subunit) genes, as well as the phosphorylation of cAMP response element-binding protein were increased after exercise. In summary, exercise appears to engage mitochondrial pathways and to potentiate neuroplasticity and might be associated to mood improvement.


Assuntos
Ansiedade/fisiopatologia , Encéfalo/fisiopatologia , Depressão/fisiopatologia , Mitocôndrias/fisiologia , Atividade Motora/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Monoaminas Biogênicas/metabolismo , Encéfalo/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Complexo I de Transporte de Elétrons/metabolismo , Comportamento Exploratório/fisiologia , Expressão Gênica/fisiologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Abrigo para Animais , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , RNA Mensageiro/metabolismo , Isolamento Social , Volição/fisiologia
20.
Arq. bras. med. vet. zootec ; 66(2): 529-538, Jan.-Apr. 2014. graf, tab
Artigo em Inglês | LILACS | ID: lil-709294

RESUMO

The aim of this study was to identify the most adequate level of calcium oxide (CaO) in the treatment of sugar cane by evaluating the chemical composition and in vitro digestibility of dry matter. The sugar cane was homogenized with CaO levels 0, 0.75, 1.5, 2.25, 3.0, 3.75 and 4.5 percent, in natura matter, for 24 hours. The dry matter and mineral matter increased, while the organic matter of the sugar cane decreased (P <0.05) linearly as a result of the CaO levels. The CaO had no effect on the levels of crude protein and ether extract. The phosphorus concentration remained unchanged, but there was a significant increase (P<0.05) in the calcium content. The contents of neutral detergent fiber, acid detergent fiber and cellulose decreased linearly with the levels of CaO. The average levels of indigestible dry matter and indigestible neutral detergent fiber significantly decreased with increasing levels of CaO. The results showed that the in vitro dry matter digestibility (IVDMD) was different between fresh sugar cane and sugar cane with added levels of CaO from 1.5 percent. The IVDMD and nutritional value of the sugar cane was improved by adding 1.5 percent CaO based on fresh content...


O objetivo foi identificar o nível mais adequado de óxido de cálcio (CaO) no tratamento da cana-de-açúcar por meio da avaliação da composição química e a digestibilidade in vitro da matéria seca. A cana-de-açúcar foi homogeneizada adicionando os níveis de CaO 0; 0,75; 1,5; 2,25; 3,0; 3,75 e 4,5 por cento em porcentagem de matéria natural, por 24 horas. Os teores de matéria seca e matéria mineral aumentaram, ao passo que o teor de matéria orgânica da cana-de-açúcar diminuiu (P<0,05) de forma linear em função dos níveis de CaO. Não houve efeito dos níveis do CaO sobre o teor de proteína bruta e extrato etéreo. Os teores médios de fósforo mantiveram-se inalterados, porém ocorreu um aumento (P<0,05) no teor de cálcio. Os teores de fibra em detergente neutro, fibra em detergente ácido e celulose diminuíram linearmente em função dos níveis de CaO. Os teores médios da matéria seca indigestível e da fibra em detergente neutro indigestível tiveram redução significativa com o aumento dos níveis de CaO. Os resultados da digestibilidade in vitro da matéria seca (DIVDM) mostraram-se diferentes entre cana-de-açúcar in natura e a com níveis de CaO. Níveis de CaO a partir de 1,5 por cento melhoram o valor nutritivo e a DIVDM da cana-de-açúcar...


Assuntos
Óxido de Cálcio , Saccharum , Saccharum/química , Bovinos , Digestão , Matéria Orgânica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...