RESUMO
BACKGROUND: Oral squamous cell carcinoma (OSCC) has high morbidity and mortality rates while oral verrucous carcinoma (OVC), an uncommon variant of OSCC, exhibits a distinct biological behavior. CLIC4 protein plays a role in the cell cycle and apoptosis regulation and participates in the myofibroblasts transdifferentiation process, which are the main cells of the tumor stroma. This study analyzed the immunoexpression of CLIC4 and α-SMA in 20 OSCC cases and 15 OVC cases. MATERIAL AND METHODS: A semiquantitative analysis of CLIC4 and α-SMA immunoexpression was performed in the parenchyma and stroma. Nuclear and cytoplasmic reactivity was analyzed separately for the CLIC4 immunostaining. The data were submitted to Pearson's chi-square and Spearman's correlation tests (p ≤ 0.05). RESULTS: In the CLIC4 analysis, there was a significant difference in the immunoexpression of this protein between OSCC and OVC stroma (p < 0.001). It was observed a higher expression of α-SMA in the OSCC stroma. There was a positive and significant correlation between CLIC4 and α-SMA immunoexpression in the OVC stroma (r = 0,612; p = 0,015). CONCLUSIONS: The decrease or absence of nuclear CLIC4 immunoexpression in the neoplastic epithelial cells and the increase of its expression in the stroma may influence the difference in biological behavior between OSCC and OVC.
Assuntos
Carcinoma de Células Escamosas , Carcinoma Verrucoso , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/patologia , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Carcinoma Verrucoso/patologia , Canais de CloretoRESUMO
BACKGROUND: Analysis of the tumor microenvironment has been proposed as a strategy for the treatment and prognosis of different neoplastic processes. A grading system based on the tumor-stroma ratio (TSR), which evaluates the proportion of stroma in relation to neoplastic parenchyma at the invasion front, has shown a strong prognostic value in different neoplastic processes. The aim of the present systematic review was to understand the role of the TSR in head and neck squamous cell carcinoma (HNSCC), evaluating its correlation with clinical and prognostic parameters. MATERIAL AND METHODS: An electronic search was performed in PubMed/Medline, Web of Science, Science Direct, Scopus, Embase, and the Cochrane Collaboration Library. Publications assessing the relationship between TSR and prognosis in cases of HNSCC were eligible. The quality of the studies was assessed independently by four evaluators using the Newcastle-Ottawa scale. RESULTS: After application of the previously es+lished inclusion/exclusion criteria, nine articles were included in the qualitative synthesis. With regards to quality on the Newcastle-Ottawa scale, an overall value of 4.55 was obtained. This systematic review demonstrated a strong association between TSR and prognosis in esophageal and oral squamous cell carcinomas. CONCLUSIONS: Histopathological analysis of the TSR can optimize the analysis of the prognosis of cases diagnosed with HNSSC. In addition, the TSR is a reliable and simple parameter that can be evaluated in hematoxylin/eosin-stained slides during routine laboratory examinations, showing high inter- and intraobserver agreement.
Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Células Estromais/patologia , Microambiente TumoralRESUMO
The aim of this study is to report the presence of a three non-native hybrid long-whiskered catfishes (family Pimelodidae) in the Upper Paraná River basin, Brazil. Genetic analyses demonstrated that the three presumptive hybrids were a result of the crossbreeding of Pseudoplatystoma reticulatum (central Amazonas River basin and Lower Paraná River) and Leiarius marmoratus (Amazonas, Essequibo and Orinoco rivers), producing a hybrid commonly known in Brazil as cachandiá. The potential threat to biodiversity, due to possible genetic contamination, competition and predation of wild stocks, of such artificially produced hybrid fishes is discussed.
Assuntos
Peixes-Gato/genética , Espécies Introduzidas , Animais , Biodiversidade , Brasil , Peixes-Gato/fisiologia , Hibridização Genética , RiosRESUMO
Here, we describe the situation of canine visceral leishmaniasis in two villages of São José de Ribamar in Maranhão State/Brazil, where human cases have been registered. Blood samples of 36 household crossbred dogs from Sergio Tamer village and 43 dogs from Quinta village were collected and the serum used for serological diagnosis. An Indirect Fluorescent Antibody Test (IFAT) and enzyme-linked immunosorbent assay (ELISA) were used to detect antibodies against Leishmania. The clinical examination showed that 25% of the canine population of Quinta presented a poor body condition and in 39%, ectoparasites (ticks and fleas) were detected. In both tests, serology revealed that 21% (9 out of 43) of the dogs presented antibodies against Leishmania (55% were asymptomatic and 45% were symptomatic). In the Vila Sérgio Tamer, 25% (9 out of 36) of the dogs were seropositive for Leishmania (66.67% were asymptomatic and 33.33% were symptomatic), 33% presented poor body condition, and 22% have ectoparasites. The clinical signs more frequent were skin lesions. The statistical analysis showed that there was no statistical difference (p>0.05) between the seropositivity of the dogs from the two villages. The same was observed when the clinical signs were compared (p>0.05). Both villages have favorable conditions to maintain the cycle of leishmaniasis.
Assuntos
Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Leishmania infantum/crescimento & desenvolvimento , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Cães , Ectoparasitoses/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Leishmaniose Visceral/parasitologia , Masculino , População Rural , Estudos SoroepidemiológicosRESUMO
Chemical modifications were used to identify some of the functionally important amino acid residues of the potato plant uncoupling protein (StUCP). The proton-dependent swelling of potato mitochondria in K(+)-acetate in the presence of linoleic acid and valinomycin was inhibited by mersalyl (K(i) = 5 microM) and other hydrophilic SH reagents such as Thiolyte MB, iodoacetate and 5, 5'-dithio-bis-(2-nitrobenzoate), but not by hydrophobic N-ethylmaleimide. This pattern of inhibition by SH reagents was similar to that of brown adipose tissue uncoupling protein (UCP1). As with UCP1, the arginine reagent 2,3-butadione, but not N-ethylmaleimide or other hydrophobic SH reagents, prevented the inhibition of StUCP-mediated transport by ATP in isolated potato mitochondria or with reconstituted StUCP. The results indicate that the most reactive amino acid residues in UCP1 and StUCP are similar, with the exception of N-ethylmaleimide-reactive cysteines in the purine nucleotide-binding site.
Assuntos
Aminoácidos/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Solanum tuberosum/metabolismo , Desacopladores/metabolismo , Trifosfato de Adenosina/antagonistas & inibidores , Compostos Bicíclicos com Pontes/metabolismo , Proteínas de Transporte/efeitos dos fármacos , Proteínas de Transporte/isolamento & purificação , Corantes Fluorescentes/metabolismo , Canais Iônicos , Proteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/isolamento & purificação , Mitocôndrias/efeitos dos fármacos , Proteínas Mitocondriais , Dilatação Mitocondrial/efeitos dos fármacos , Solanum tuberosum/química , Proteína Desacopladora 1RESUMO
Chemical modifications were used to identify some of the functionally important amino acid residues of the potato plant uncoupling protein (StUCP). The proton-dependent swelling of potato mitochondria in K+-acetate in the presence of linoleic acid and valinomycin was inhibited by mersalyl (Ki = 5 æM) and other hydrophilic SH reagents such as Thiolyte MB, iodoacetate and 5,5'-dithio-bis-(2-nitrobenzoate), but not by hydrophobic N-ethylmaleimide. This pattern of inhibition by SH reagents was similar to that of brown adipose tissue uncoupling protein (UCP1). As with UCP1, the arginine reagent 2,3-butadione, but not N-ethylmaleimide or other hydrophobic SH reagents, prevented the inhibition of StUCP-mediated transport by ATP in isolated potato mitochondria or with reconstituted StUCP. The results indicate that the most reactive amino acid residues in UCP1 and StUCP are similar, with the exception of N-ethylmaleimide-reactive cysteines in the purine nucleotide-binding site
Assuntos
Animais , Bovinos , Aminoácidos/metabolismo , Proteínas de Transporte/metabolismo , Mitocôndrias/metabolismo , Solanum tuberosum/metabolismo , Desacopladores/metabolismo , Compostos Bicíclicos com Pontes/metabolismo , Proteínas de Transporte/isolamento & purificação , Corantes Fluorescentes/metabolismo , Dilatação Mitocondrial , Solanum tuberosum/químicaRESUMO
BACKGROUND: The MACIS score uses metastasis, age, completeness of resection, local invasion, and tumor size to stratify patients with papillary thyroid carcinoma (PTC) into four groups with different survival. METHODS: Immunostaining for proliferating cell nuclear antigen (PCNA) was done in 43 cases of PTC. Relationships between proliferative index (percentage of cells that were PCNA positive) and the MACIS parameters were examined. Double staining for PCNA and for silver-stained nucleolar organizer regions (AgNORs, indicating proliferation) was performed in 10 cases. RESULTS: PCNA was detected only in tumor cells. The proliferative index was low (mean, 14.2%; median, 13.0%), did not differ between MACIS groups (p = 0.56), and showed no association with individual MACIS parameters. PCNA immunostaining correlated with AgNOR staining. The mean AgNOR count was 2.28 in PCNA-positive cells and 1.85 in PCNA-negative cells (p
Assuntos
Carcinoma Papilar/patologia , Região Organizadora do Nucléolo/patologia , Antígeno Nuclear de Célula em Proliferação/análise , Neoplasias da Glândula Tireoide/patologia , Adulto , Idoso , Biópsia por Agulha , Carcinoma Papilar/diagnóstico , Carcinoma Papilar/secundário , Carcinoma Papilar/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/cirurgiaRESUMO
In the present study we have observed a higher state of coupling in respiring mitochondria isolated from green as compared to red tomatoes (Lycopersicon esculentum, Mill.). Green tomato mitochondria produced a membrane potential (deltapsi) high enough to phosphorylate ADP, whereas in red tomato mitochondria, BSA and ATP were required to restore deltapsi to the level of that obtained with green tomato mitochondria. This supports the notion that such uncoupling in red tomato mitochondria is mediated by a plant uncoupling mitochondrial protein (PUMP; cf. Vercesi et al., 1995). Nevertheless, mitochondria from both green and red tomatoes exhibited an ATP-sensitive linoleic acid (LA)-induced deltapsi decrease providing evidence that PUMP is also present in green tomatoes. Indeed, proteoliposomes containing reconstituted green or red tomato PUMP showed LA uniport and LA-induced H+ transport. It is suggested that the higher concentration of free fatty acids (PUMP substrates) in red tomatoes could explain the lower coupling state in mitochondria isolated from these fruits.
Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Solanum lycopersicum/metabolismo , Desacopladores/metabolismo , Animais , Proteínas de Transporte/isolamento & purificação , Ácidos Graxos/metabolismo , Membranas Intracelulares/fisiologia , Canais Iônicos , Solanum lycopersicum/crescimento & desenvolvimento , Proteínas de Membrana/isolamento & purificação , Mitocôndrias/fisiologia , Proteínas Mitocondriais , Proteolipídeos/metabolismo , Prótons , Proteína Desacopladora 1RESUMO
A variety of plant tissues contain an uncoupling mitochondrial protein (PUMP), recently described and characterized by our group. In this study we show that the inhibition of PUMP activity in potato tuber mitochondria significantly increases mitochondrial H2O2 generation, while PUMP substrates, such as linoleic acid, reduce mitochondrial H2O2 generation. This H2O2 generation occurred mainly by the dismutation of superoxide radicals formed through monoelectronic reduction of O2 by semiquinone forms of coenzyme Q. The results presented suggest that protection against mitochondrial oxidative stress may be a physiological role of PUMP.
Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Cálcio/metabolismo , Cálcio/farmacologia , Transporte de Elétrons , Peróxido de Hidrogênio/metabolismo , Canais Iônicos , Ácido Linoleico/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Proteínas Mitocondriais , Ratos , Soroalbumina Bovina/metabolismo , Soroalbumina Bovina/farmacologia , Solanum tuberosum/metabolismo , Proteína Desacopladora 1RESUMO
Peroxynitrite anion, the reaction product of superoxide and nitric oxide, is a potent biological oxidant, which inactivates mammalian heart mitochondrial NADH-coenzyme Q reductase (complex I), succinate dehydrogenase (complex II), and ATPase, without affecting cytochrome c oxidase (complex IV). In this paper, we evaluated the effect of peroxynitrite on mitochondrial membrane integrity and permeability under low calcium concentration. Phosphate buffer was used in most of our experiments since Hepes, Tris, mannitol, and sucrose were found to inhibit the oxidative chemistry of peroxynitrite. Peroxynitrite (0.1-1.0 mM) caused a dose-dependent decrease in the ability of mitochondria to build up a membrane potential when N,N,N',N'-tetramethyl-p-phenylenediamine/ascorbate were used as substrate. Elimination of the membrane potential was accompanied by penetration of the osmotic support (KCl/NaCl) into the matrix as judged by the parallel occurrence of mitochondrial swelling. This swelling was partially inhibited by dithiothreitol (DTT) or butylated hydroxytoluene (BHT) and was insensitive to ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid, ADP, and cyclosporin A. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of solubilized membrane proteins indicated that alterations in membrane permeability were associated with the production of protein aggregates due to membrane protein thiol cross-linking. The protective effect of DTT on both mitochondrial swelling and protein polymerization suggests the involvement of disulfide bonds in the membrane permeabilization process. In addition, the increase in thiobarbituric acid-reactive substances and the partial inhibitory effect of BHT indicate the occurrence of lipid peroxidation. These results support the idea that under our experimental conditions peroxynitrite causes mitochondrial structural and functional alterations by Ca2+-independent mechanisms through lipid peroxidation and protein sulfhydryl oxidation.