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Biomateriaistem diversas indicações como auxiliares no processo de reparação óssea, além de terem função de substituto ósseo em perdas extensas. Diversas são as vantagens de sua utilização, como por exemplo, auxílio na osteocondutividade, estímulo de neovascularização, potencial antimicrobiano, entre outros. Falhas ósseas foram realizadas nas tíbias de seis ovinos da raça Santa Inês e preenchidas com biomaterial à base de quitosana, colágeno e hidroxiapatita. Um membro foi considerado controle e outro membro tratado segundo estudo randomizado. Foram realizadas avaliações termográficas e por ultrassonografia Power Dopplerem todos os animais do estudo, semanalmente, nos dias D0, D7, D14, D21, D28, D35, D42 e D56. Não houve diferenças significativas com relação à temperatura mínima, máxima e média entre os grupos com biomaterial e controle nas imagens termográficas. Houveram variações com relação ao tempo dentro de ambos os grupos. Com relação à presença de vasos na ultrassonografia Power Dopplernão houve diferenças estatísticas entre os grupos, exceto no dia 21 (P=0,031). Dentro das possibilidades de avaliação que os exames de imagem fornecem, a termografia e a ultrassonografia Power Dopplermostraram-se ferramentas não invasivas de avaliação pós-operatória de processo inflamatório e neovascularização, sendo realizadas semanalmente, permitindo acompanhamento fidedigno e detalhado ao longo do experimento, sem gerar desconforto ou estresse aos animais. Não houve indícios de complicações relacionadas ao biomaterial.(AU)

Biomaterials have several indications supporting the bone repair process, besides having bone substitute function in extensive losses. There are several advantages of its use, such as contribution in osteoconductivity, stimulation of neovascularization, antimicrobial potential, among others.Tibial bone defects was performed in six Santa Inês breed ewes and implanted with chitosan, collagen and hydroxyapatite biomaterial. One limb was considered the control limb and the other one the biomateriallimb, chosenrandomly. Thermographic and Power Dopplersonography was performed in all animals, weekly for 56 days. The thermography showed no significant differences related to low, high and mean temperature between the control and the biomaterial groups. Statisticalvariations were found between time in both groups. The visualization of neovascularization with the Power Dopplersonography did not present statistical differences, except for day 21 (P=0,031). Within the possibilities provided by imaging exams, thermography and Power Doppler sonography demonstrate to be non-invasive methods for post-operative evaluation of inflammatory process and neovascularization. The weekly management allowed reliable and detailed monitoring throughout the experiment, without causingdiscomfort or stress to the animals. There was no evidence of biomaterial complications.(AU)

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Purpose: To investigate putative mechanism of wound healing for chitosan-based bisacurone gel against secondary burn wounds in rats. Methods: A second-degree burn wound with an open flame using mixed fuel (2 mL, 20 seconds) was induced in Sprague Dawley rats (male, 180-220 g, n = 15, each) followed by topical treatments with either vehicle control (white petroleum gel, 1%), silver sulfadiazine (1%) or bisacurone gel (2.5, 5, or 10%) for 20 days. Wound contraction rate and paw withdrawal threshold were monitored on various days. Oxidative stress (superoxide dismutase, glutathione, malondialdehyde, and nitric oxide), pro-inflammatory cytokines (tumour necrosis factor-alpha, interleukins by enzyme-linked immunosorbent assay), growth factors (transforming growth factor-ß, vascular endothelial growth factor C using real time polymerase chain reaction and Western blot assay) levels, and histology of wound skin were assessed at the end. Results: Bisacurone gel showed 98.72% drug release with a 420.90­442.70 cps viscosity. Bisacurone gel (5 and 10%) significantly (p < 0.05) improved wound contraction rate and paw withdrawal threshold. Bisacurone gel attenuated oxidative stress, pro-inflammatory cytokines, and water content. It also enhanced angiogenesis (hydroxyproline and growth factor) and granulation in wound tissue than vehicle control. Conclusions: These findings suggested that bisacurone gel can be a potential candidate to treat burn wounds via its anti-inflammatory, antioxidant, and angiogenic properties.

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Purpose: Esophageal squamous cell carcinoma (ESCC) is characterized by early metastasis and late diagnosis. miR-29c-3p is confirmed to repress angiogenesis in multiple tumor types. Yet, the functions of miR-29c-3p in the mechanism of ESCC angiogenesis, which were not sufficiently explored previously, were exactly what we investigated here at the molecular level. Methods: The mRNA level of miR-29c-3p and Serpin peptidase inhibitor clade H member 1 (SERPINH1) in ESCC tissues were assessed via bioinformatics analysis. Thereafter, miR-29c-3p and SERPINH1 (HSP47) mRNA level in ESCC cell lines was evaluated via quantitative real-time polymerase chain reaction. The effects of abnormal miR-29c-3p and SERPINH1 expression on ESCC cell viability, proliferation, migration, invasion, and HUVEC angiogenesis were examined via CCK8, colony formation, transwell, and angiogenesis assays, respectively. The protein levels of SERPINH1, vascular endothelial growth factor-A (VEGFA), Wnt-1, ?-catenin, and p-?-catenin were evaluated via Western blot. Expression of VEGFA secreted by ESCC cells was measured via enzyme-linked immunosorbent assay. Treatment with the Wnt activator BML-284 further revealed the way miR-29c-3p mediated the Wnt signaling pathway and its effects on angiogenesis. Results: Herein, we revealed a decrease of miR-29c-3p expression in ESCC tissues and cells, while the overexpressed miR-29c-3p could remarkably suppress ESCC cell progression, as well as HUVEC angiogenesis. Meanwhile, overexpressed miR-29c-3p notably downregulated VEGFA and repressed the Wnt signaling pathway. Treatment with the Wnt activator BML-284 could reverse the inhibition of HUVEC angiogenesis caused by miR-29c-3p. SERPINH1 was a downstream target of miR-29c-3p. SERPINH1 knockdown suppressed the malignant phenotypes of ESCC cells and impeded the Wnt signaling activation, while such suppression was reversed through miR-29c-3p inhibitor. Conclusions: We confirmed the mechanism that miR-29c-3p targeted SERPINH1, thus regulating angiogenesis in ESCC through the Wnt signaling pathway. It improves the understanding of angiogenesis in ESCC and offers new ideas for the research of ESCC treatment strategies in the future.

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Background Cathepsin D (CatD) is a lysosomal proteolytic enzyme expressed in almost all tissues and organs. This protease is a multifunctional enzyme responsible for essential biological processes such as cell cycle regulation, differentiation, migration, tissue remodeling, neuronal growth, ovulation, and apoptosis. The overexpression and hypersecretion of CatD have been correlated with cancer aggressiveness and tumor progression, stimulating cancer cell proliferation, fibroblast growth, and angiogenesis. In addition, some studies report its participation in neurodegenerative diseases and inflammatory processes. In this regard, the search for new inhibitors from natural products could be an alternative against the harmful effects of this enzyme. Methods An investigation was carried out to analyze CatD interaction with snake venom toxins in an attempt to find inhibitory molecules. Interestingly, human CatD shows the ability to bind strongly to snake venom phospholipases A2 (svPLA2), forming a stable muti-enzymatic complex that maintains the catalytic activity of both CatD and PLA2. In addition, this complex remains active even under exposure to the specific inhibitor pepstatin A. Furthermore, the complex formation between CatD and svPLA2 was evidenced by surface plasmon resonance (SPR), two-dimensional electrophoresis, enzymatic assays, and extensive molecular docking and dynamics techniques. Conclusion The present study suggests the versatility of human CatD and svPLA2, showing that these enzymes can form a fully functional new enzymatic complex.

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Snake venoms are composed of pharmacologically active proteins that are evolutionarily diverse, stable and specific to targets. Hence, venoms have been explored as a source of bioactive molecules in treating numerous diseases. Recent evidences suggest that snake venom proteins may affect the formation of new blood vessels. Excessive angiogenesis has been implicated in several pathologies including tumours, diabetic retinopathy, arthritis, inter alia. In the present study, we have examined the effects of P-I metalloproteinases isolated from Bothrops moojeni (BmMP-1) and Bothrops atrox (BaMP-1) and L-amino acid oxidases (LAAO) isolated from B. moojeni (BmLAAO) and B. atrox (BaLAAO) on biochemical and functional aspects of angiogenesis. Methods: P-I metalloproteinases and LAAO were purified from venom by molecular size exclusion and ion-exchange chromatography and subsequently confirmed using mass spectrometry. The P-I metalloproteinases were characterized by azocaseinolytic, fibrinogenolytic and gelatinase activity and LAAO activity was assessed by enzyme activity on L-amino acids. Influence of these proteins on apoptosis and cell cycle in endothelial cells was analysed by flow cytometry. The angiogenic activity was determined by in vitro 3D spheroid assay, Matrigel tube forming assay, and in vivo agarose plug transformation in mice. Results: P-I metalloproteinases exhibited azocaseinolytic activity, cleaved α and partially β chain of fibrinogen, and displayed catalytic activity on gelatin. LAAO showed differential activity on L-amino acids. Flow cytometry analysis indicated that both P-I metalloproteinases and LAAO arrested the cells in G0/G1 phase and further induced both necrosis and apoptosis in endothelial cells. In vitro, P-I metalloproteinases and LAAO exhibited significant anti-angiogenic properties in 3D spheroid and Matrigel models by reducing sprout outgrowth and tube formation. Using agarose plug transplants in mice harbouring P-I metalloproteinases and LAAO we demonstrated a marked disruption of vasculature at the periphery. Conclusion: Our research suggests that P-I metalloproteinases and LAAO exhibit anti-angiogenic properties in vitro and in vivo.(AU)

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Bortezomib, an inhibitor of 26S proteasome, is an anti-cancer therapeutic agent used in different cancer types. It leads to the arrest of the cancerous cell cycle by inhibiting angiogenesis and inducing apoptosis. Liver is the vital organ for detoxification and excretion of toxic products. The treatment with chemotherapy is a challenge, drugs are used to destroy cancer cells, but healthy cells can be affected during cancer treatment as well. The main objective of this study was to analyze the histopathological and biochemical effects of bortezomib on liver. Twenty-four female C57BL/6 mice were distributed into 4 groups, bortezomib injected treatment groups (Btz1, Btz2) and saline injected control groups (C1, C2). Bortezomib and saline were treated twice per week for 6 weeks and sacrificed at the end of one day (Btz1, C1) and 4 weeks (Btz2, C2) after the last injection. Liver samples were examined for histopathological analysis and the serum samples processed for biochemical analysis. Tissue samples were fixed, routinely processed, sectioned, and stained with Hematoxylin and Eosin (H&E). Periodic Acid-Schiff (PAS), Sudan Black staining and Masson's trichrome histochemical staining methods were performed to characterize the lesions. Histopathological analysis of the Btz1 and Btz2 groups revealed acute hepatic morphological changes such as hepatocellular swelling (cloudy swelling), necro-inflammatory reaction, and increased mononuclear polyploidy. Based on the negative staining with PAS and Sudan Black staining, hepatocellular swelling was diagnosed as hydropic degeneration. Necro-inflammatory reaction observed in the form of acute hepatitis was composed of mainly mononuclear cell infiltration accompanied by multifocal necrotic foci. Kupffer cell proliferation was observed in parallel with degenerative and necrotic changes. An Increase in hepatocellular mononuclear polyploidy visualized as hepatocytes with a single enlarged nucleus was detected in all liver sections of Btz1 and Btz2 groups. Individual cases of cholestasis (n = 1) and mild hepatic fibrosis (n = 1) were also reported. Significant elevated levels of alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) were detected in bortezomib treated groups. Few clinical cases reported liver injury related to bortezomib used for cancer treatment. However, the liver was not considered as a target for bortezomib treatment. Our data suggesting that bortezomib caused liver damage and induces elevations in serum levels. The reported hepatic lesions including hepatocellular swelling, acute hepatitis and mononuclear polyploidy were mainly mild and moderate in severity. The increase of polyploidy in liver tissue of mice treated with bortezomib in this study was explained as a reaction of the liver facing the drug-induced hepatic damage. The mechanism leading to the hepatotoxicity of bortezomib treatment is not known but the production of a toxic metabolite through its metabolism in the liver can be suggested. Moreover, no recovery was also observed in histopathological and biochemical analyses suggesting that the bortezomib effect is non-reversible four weeks after the drug was withdrawn. Patients should be informed about the possibility of acute drug-induced hepatitis and hepatotoxicity of this chemotherapeutic agent after the treatment.(AU)

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The canine mammary tumor is the neoplasia that most commonly affects intact female dogs (not spayed) in routine veterinary practice. Canine mammary tumor therapy is a challenge because only few effective treatments have been described for high-grade tumors in veterinary medicine. One such therapeutic option that slows down tumor growth is metronomic chemotherapy (MC), a therapeutic modality that acts by decreasing tumor angiogenesis. Quantification of intratumoral microvessel density (MVD) has been proposed as a means to evaluate the effectiveness of MC in human and canine tumors. In this study, MVD is proposed as a predictive factor for the effectiveness of MC in canine mammary tumors. Twenty female dogs with mammary carcinoma were equally distributed into a mastectomy group treated only with mastectomy, and a MC group treated with MC (cyclophosphamide and piroxicam) orally and daily for 28 days followed by mastectomy. Mammary tumors were classified and graded histologically. MVD was ascertained by CD31 immunostaining. The analysis showed statistically significant difference in MVD scores between groups, corroborating a quantitative reduction in tumor microvasculature in the group treated with MC. Our findings suggest that MVD may be an important predictive factor for the selection of female dogs with malignant mammary tumors that may benefit from MC.

O tumor mamário canino é a neoplasia que mais comumente acomete cadelas não castradas na rotina veterinária. A terapia para a neoplasia mamária canina é um desafio, com poucos tratamentos eficazes descritos em medicina veterinária, especialmente para as neoplasias de alto grau. Uma opção terapêutica que diminui o crescimento tumoral é a quimioterapia metronômica (QM). A QM é uma modalidade terapêutica que age pelo decréscimo da angiogênese tumoral. Para avaliação da eficácia da QM tem sido proposta a quantificação da densidade microvascular (DMV) em neoplasias caninas. Neste estudo foi proposta a mensuração da DMV como fator preditivo à utilização da QM em neoplasias mamárias caninas. Foram utilizadas 20 (vinte) cadelas com carcinomas mamários malignos sendo um grupo mastectomia, tratado somente por mastectomia, e um grupo QM, em que foi empregada a QM (ciclofosfamida e piroxicam) ambos oralmente e de uso diário por 28 dias seguida de mastectomia. As neoplasias mamárias foram histologicamente classificadas e graduadas. A DMV foi obtida por imunomarcação utilizando o anticorpo CD31. A análise estatística mostrou diferença na DMV entre os grupos, evidenciando redução quantitativa na microvasculatura tumoral no grupo tratado com quimioterapia metronômica. Com base neste resultado é possível afirmar que a DMV pode vir a ser um fator preditivo de importância para a seleção de cadelas portadoras de neoplasia mamária maligna que possam vir a se beneficiar da quimioterapia metronômica.

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RESUMO O fator de crescimento endotelial vascular (VEGF) é um importante regulador da angiogênese, sendo apontado como um fator de crescimento autócrino para células neoplásicas de diversos tumores. O objetivo do presente estudo foi avaliar a expressão de VEGF em mastocitomas caninos e sua metástase regional como marcador de prognóstico. Foram selecionadas 28 pacientes com mastocitoma com metástase em linfonodo regional confirmada e as amostras foram submetidas a análise por imunohistoquimica. Dos pacientes avaliados apenas 14,3% expressaram VEGF em tumor e metástase, com concordância leve. Houve uma correlação fraca entre o tamanho tumoral. Não houve diferença de sobrevida entre positivos em tumor primário e metástase e os negativos. A expressão de VEGF não apresentou correlação com a sobrevida dos pacientes, no entanto, pacientes com expressão positiva pode se beneficiar com terapia inibidora deste fator.

Vascular endothelial growth factor (VEGF) is an important regulator of angiogenesis, being indicated as an autocrine growth factor for neoplastic cells of several tumors. The aim of the present study was to evaluate VEGF expression in canine mast cell tumors and its regional metastasis as a prognostic marker. Twentyeight patients with mast cell tumors with confirmed regional lymph node metastasis were selected and the samples were submitted to immunohistochemical analysis. Of the patients evaluated, only 14.3% expressed VEGF in tumor and metastasis, with mild agreement. There was a weak correlation between tumor size. There was no difference in survival between positives in primary tumor and metastasis and negatives. VEGF expression did not correlate with patient survival, however, patients with positive expression may benefit from inhibitor therapy of this factor.

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Metronomic chemotherapy consists of an anticancer modality treatment. It is applicable in patients at an advanced stage, with the objective of increasing overall survival. The aim of this study was to report an anal sac apocrine carcinoma case in a dog with lymph node metastasis treated with metronomic chemotherapy sequential to surgery and conventional chemotherapy using gemcitabine and carboplatin. Metronomic chemotherapy was associated with cyclooxygenase-2 (COX-2) inhibitors, due to strong tumor COX-2 immunohistochemistry expression. Metronomic chemotherapy was initiated with cyclophosphamide, but it was replaced by lomustine, also in metronomic dosage, due to adverse effects. Treatment showed effectiveness, since the patient's overall survival exceeded 1095 days (36 months), considerably higher than the mean overall survival expected for this pathology.(AU)

Quimioterapia metronômica consiste em uma modalidade de tratamento anticancerígeno, aplicável a pacientes em estadiamento avançado, com o objetivo de aumentar a sobrevida global. O objetivo deste trabalho foi relatar um caso de carcinoma apócrino do saco anal, em uma cadela, com metástase em linfonodo tratado com quimioterapia metronômica sequencial à cirurgia e quimioterapia convencional utilizando-se gencitabina e carboplatina. O tratamento metronômico foi associado ao uso de inibidores de ciclo-oxigenase-2 (COX-2), baseando-se na constatação de sua expressão tumoral. A terapia metronômica iniciou-se com ciclofosfamida, mas houve necessidade de substituição pela lomustina, também em dose metronômica, devido à ocorrência de efeitos adversos. O tratamento mostrou ser eficaz, pois a sobrevida do paciente ultrapassa 1095 dias (36 meses) desde a cirurgia, sendo consideravelmente maior que a média relatada para essa patologia.(AU)

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ABSTRACT PURPOSE : To compare ileal anastomoses in the immediate postoperative healing period after meloxicam use. METHODS: Forty two male Wistar rats were randomly divided into two groups of 21, COX and control group. To COX meloxicam in combination with morphine was given in 3 days period. Control group received only morphine during the same period. Each group was divided into three sub-groups of 7, which were euthanized at 5, 10, and 21 days postoperatively. Comparison was based in histological evaluation of collagen type I and III using sirius red, immunohistochemical through vascular endothelial growth factor and matrix metalloproteinase-9. RESULTS: Healing process in scheduled periods did not show significant differences (p>0.05) between the COX and control groups during any of the periods. CONCLUSION: The use of meloxicam in the postoperative period following ileal anastomosis did not affect healing.

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AbstractTo assess the pro-angiogenic activity of Euphorbia tirucalli, commonly known as “avelós” plant, we performed a series of tests by applying an aqueous E. tirucalli latex solution (10 mg/mL) to the chorioallantoic membranes (CAMs) of 80 fertilized chicken eggs incubated in a temperature- and humidity-controlled automatic incubator. The results indicated that the aqueous latex solution increased vascular network formation compared to that with the negative control (p < 0.05) and the inhibitor control (p < 0.05). This suggests that under the experimental conditions tested, the aqueous latex solution induced an inflammatory response leading to neoangiogenesis.

ResumoCom o objetivo de analisar a atividade angiogênica apresentada pela Euphorbia tirucalli, popularmente conhecida comumente como “avelós”, foram realizados ensaios utilizando solução aquosa de látex na concentração de 10 mg/ml, aplicada em membrana corioalantóide (MCA) de 80 ovos férteis de galinha, incubado em estufa automática com temperatura e umidade controladas. Os resultados apontaram que a ação da solução aquosa provocou aumento da percentagem da rede vascular formada em relação aos controles negativo (p<0,05) e inibidor (p<0,05), indicando que nas condições deste experimento, foi responsável pela ativação da resposta inflamatória e crescimento de novos vasos sanguíneos.

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O carcinoma prostático canino possui prognóstico desfavorável e modalidades terapêuticas limitadas, principalmente em casos avançados. Devido à falta de tratamento eficaz para os carcinomas prostáticos caninos, esse estudo objetivou avaliar o efeito do toceranib (inibidor de receptor tirosina quinase) e da rapamicina (inibidor de mTORC1) em células de carcinoma prostático canino. As duas células de cultura primária advindas de carcinoma prostático canino, denominadas PC1 e PC2, apresentaram expressão proteica de VEGFR2 e PDGFR- e ausência da proteína c-KIT, os quais são alvos do fosfato de toceranib. Adicionalmente, após comparação do transcriptoma das células não tratadas e tratadas com fosfato de toceranib, observaram-se alterações em genes relacionados com a via PDGFR, angiogênese e resistência terapêutica. Além disso, realizou-se o tratamento das células PC1 e PC2 com rapamicina (inibidor de mTORC1) após a comparação do transcriptoma das células tumorais com células de próstata normal e identificação de genes envolvidos na via PI3K/AKT/mTOR. O tratamento com rapamicina diminuiu a expressão gênica de mTOR e 4E-BP1 e aumentou de AKT, podendo representar mecanismos de resistência. Após tratamento com fosfato de toceranib, apenas a PC1 reduziu a viabilidade celular, porém após tratamento com rapamicina, as células PC1 e PC2 reduziram a viabilidade celular de maneira dose dependente, havendo resposta biológica em ambas as terapias. Sendo assim, o bloqueio de múltiplos receptores tirosina quinase e inibição de mTOR representam alvos terapêuticos no carcinoma prostático canino, entretanto a resistência terapêutica ainda é desafiadora e, portanto, a medicina de precisão seria uma forma de superar o problema.

Canine prostatic carcinoma has a poor prognosis and limited therapeutic modalities, mainly in advanced cases. The aim of this study was to evaluate the effect of toceranib phosphate (receptor tyrosine kinase inhibitor) and rapamycin (mTORC1 inhibitor) in canine prostatic carcinoma cells due to the lack of efficient therapies. Two primary canine prostate cancer cell lines, PC1 and PC2, had protein expression of VEGFR2 and PDGFR- and absent c-KIT expression, which are target toceranib phosphate targets. Additionally, we compared transcriptome before and after toceranib phosphate treatment and we observed gene alterations related to PDGFR pathway, angiogenesis and therapeutic resistance. Besides, we treated PC1 and PC2 cells with rapamycin after transcriptome analysis comparing canine prostatic cells from normal prostate and neoplastic cells and identification of genes involved in PI3K/AKT/mTOR pathway. Gene expression of mTOR and 4E-BP1 decreased and AKT increased after rapamycin treatment, and could represent a resistency mechanism. A decrease only in PC1 cell viability was observed after toceranib phosphate treatment, however decreased cell viability in a dose-dependent manner was observed in PC1 and PC2 cells after rapamycin treatment. Therefore, we could observe biological response of canine prostatic carcinoma cells to both therapies. Thus, multiple receptor tyrosine kinase inhibition and mTOR inhibition represent target therapies to canine prostatic carcinoma. However, therapeutic resistance still remains a challenge and precision medicine could be a way to overcome this problem.

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O HER2 é um marcador prognóstico e preditivo amplamente utilizado em câncer de mama de mulheres e a sua superexpressão está ligada à um menor tempo livre de doença, diminuição da expressão de receptores de estrógeno e progesterona, maior taxa de proliferação e migração celular, invasividade tumoral, frequência de metástases, angiogênese e diminuição da apoptose. Nas neoplasias mamárias de cães, o papel do HER2 ainda não está satisfatoriamente esclarecido, porém já foi observado que sua superexpressão está relacionada com pleomorfismo celular e aumento do número de figuras de mitoses, sendo que esta relação também já foi notada em mulheres. O lapatinibe é um inibidor tirosina-quinase que age bloqueando a fosforilação dos receptores HER2. O seu uso está relacionado com melhores resultados no tratamento em mulheres com tumores HER2+. Nesse estudo, objetivou-se verificar os efeitos do lapatinibe em cultura celular in vitro, provenientes de carcinoma mamário canino primário e metastático. Quatro culturas celulares de carcinoma mamário primário e duas metástases previamente estabelecidas e caracterizadas foram expandidas, tratadas com lapatinibe nas concentrações de 0.1, 0.5, 1 e 3M, por 24h, e tiveram a sua concentração inibitória de 50% das células (IC50) determinado. Além disso, verificamos a expressão de HER2 de todas as culturas celulares. A IC50 das células variou de 0.01 até 0.58M. Ademais, o lapatinibe foi capaz de inibir a viabilidade de todas as culturas celulares tratadas, sendo que quanto maior a expressão de HER2 de uma cultura, mais sensível ela foi ao lapatinibe. Portanto, o tratamento com lapatinibe pode ser uma opção promissora para pacientes caninos com carcinoma mamário primário ou metastático, podendo ser utilizado principalmente em animais com neoplasias HER2+.

HER2 is a prognostic and predictive marker widely used in breast cancer diagnosys in women and its overexpression is linked to shorter disease-free survival, decreased expression of estrogen and progesterone receptors, higher proliferation rate and cell migration, tumor invasiveness, frequency of metastases, angiogenesis and decreased apoptosis. In the mammary neoplasms of dogs, the role of HER2 is not yet satisfactorily clarified, however it has already been observed that its overexpression is related to cellular pleomorphism and increased numbers of mitosis figures. This relationship has also been noticed in women. Lapatinib is a tyrosine kinase inhibitor that acts by blocking the phosphorylation of HER2 receptors. Its use is linked to better results in the treatment of women with HER2+ tumors. The aim was to access the effects of lapatinib on primary and metastatic canine mammary gland carcinoma cell cultures in vitro. Cell cultures from four primary mammary carcinoma and two metastases that were previously established and characterized were expanded, treated with lapatinib at concentrations of 0.1, 0.5, 1 and 3M, for 24h, and had their inhibitory concentration of 50% of the cells (IC50) determined. In addition, we verified the expression of HER2 from all cell cultures. The IC50 of the cells ranged from 0.01 to 0.58 M. Furthermore, lapatinib was able to inhibit the viability of all treated cell cultures The higher the expression of HER2 in a culture the more sensitive it was to lapatinib. Therefore, treatment with lapatinib can be a promising option for canine patients with primary or metastatic mammary gland carcinoma and can be used especially in animals with HER2+ neoplasms.

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As neoplasias mamárias representam pouco mais da metade dos tumores que acometem as cadelas comuma grande parcela de tumores malignos. Elas são menos comuns em gatas, no entanto comumente sãomalignas. O fator de crescimento endotelial (VEGF) é importantíssimo na formação das glândulas mamárias nodesencadeamento da angiogênese normal e induzida por tumores, influenciando o prognóstico dos pacientes comneoplasias mamárias. Portanto, a identificação por meio de marcadores específicos para o VEGF e seusreceptores pode servir como fonte de informações sobre a característica de agressividade das neoplasias demama, estabelecendo-se, assim, um prognóstico. Acrescenta-se, ainda, a possibilidade de emprego de drogasantiangiogênicas, que atuam inibindo a função do VEGF como forma de controle de progressão tumoral esurgimento ou evolução de metástases. Contudo, pesquisas na medicina veterinária ainda são escassas, embora oemprego dessas drogas com sucesso em humanos e em animais de laboratório encoraja a necessidade de maisestudos sobre o envolvimento do VEGF em tumores mamários de cadelas e gatas.

The mammary neoplasias represents more than half of the tumors that affect bitches, grand part beingmalignant tumors. They are less common in cats, although the majority is malignant tumors. The vascularendothelial growth factor (VEGF) is very important during the mammary gland development, normal and tumorinduced angiogenesis and influences the prognosis of patients with mammary neoplasias. Therefore, the assistedVEGF specific markers and for its receptors identification may be a useful source of information about themammary gland tumor aggressiveness and a helpful tool for a more precise prognosis. Additionally antiangiogenic drugs, acting as VEGF inhibitor, may be a control form of tumor progression, metastasis appearanceand evolution. Veterinary research in this field are scarce, although the success use of these drugs in human andlaboratory animals encourage the studies about VEGF involvement in dogs and cats mammary tumors.

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Toxoplasmosis is caused by Toxoplasma gondii, which is the main causative agent of abortion in small ruminants. Goats are among the animals that are most susceptible to this protozoon, and the disease that it causes leads to significant economic losses and has implications for public health, since presence of the parasite in products of goat origin is one of the main sources of human infection. Because of the significant economic impact, there is an urgent need to study the prevalence of T. gondii infection among goats in Sertão do Cabugi, which is the largest goat-producing region in Rio Grande do Norte. In the present study, the ELISA assay was used to test 244 serum samples from nine farms, located in four different municipalities in the Sertão do Cabugi region, which is an important goat-rearing region. The results showed that the prevalence of anti-T. gondii antibodies was 47.1% and that there was a significant association between positivity and the variables of age (≥ 34 months), location (Lajes, Angicos and Afonso Bezerra) and farm (all the farms). The avidity test was applied to all the 115 ELISA-positive samples to distinguish between acute and chronic infection. One hundred and three samples (89.6%) displayed high-avidity antibodies, thus indicating that most of the animals presented chronic infection, with a consequent great impact on the development of the goat production system and a risk to human health.

A toxoplasmose é causada pelo Toxoplasma gondii, principal agente causador de aborto em pequenos ruminantes. Os caprinos são uns dos animais mais suscetíveis a esse protozoário, levando a perdas econômicas significativas e implicações para a saúde pública, uma vez que a presença do parasito em produtos de origem caprina é uma das principais fontes de infecção humana. Devido ao impacto econômico significativo torna-se urgente estudar a prevalência da infecção, pelo T. gondii, entre caprinos do Sertão do Cabugi, a maior região produtora de caprinos no Rio Grande do Norte. O presente estudo utilizou o ELISA para testar 244 amostras de soro de 9 fazendas, situadas em 4 diferentes cidades na região do Sertão do Cabugi; uma importante região de criação de cabras. Os resultados mostraram uma prevalência de 47,1% para anticorpos anti- T. gondii e uma significativa associação entre a positividade e as variáveis idade (≥ 34 meses), localização (Lajes, Angicos e Afonso Bezerra e propriedade (todas as fazendas). O teste de avidez foi aplicado a todas as 115 amostras positivas pelo ELISA para discriminar entre infecção aguda e crônica. Cento e três amostras (89,6%) apresentaram anticorpos de alta avidez; indicando que a maioria dos animais estavam em infecção crônica, gerando um grande impacto sobre o desenvolvimento do sistema de produção em cabras e um risco para a saúde humana.

Resumo

O fenômeno da luteólise é conhecido como o processo em que o corpo lúteo (CL) sofre regressão, caracterizada inicialmente por uma diminuição na concentração plasmática de progesterona (P4). A luteólise é bastante complexa e envolve vários processos desencadeados a partir do não reconhecimento da gestação e do aumento na liberação pulsátil de prostaglandina F2α (PGF2α). O aumento na pulsatilidade está envolvido com o aumento de receptores endometriais para ocitocina e estrógeno. Quando altas concentrações de PGF2α se ligam aos receptores no CL, desencadeiam uma série de alterações nas expressões gênicas dos fatores angiogênicos e vasoativos, que influenciam direta ou indiretamente no CL. As alterações nas expressões gênicas são necessárias para aumentar ainda mais as concentrações de PGF2α intraluteal, consequentemente diminuir as concentrações de P4 e regredir o tecido luteínico. Assim sendo, o objetivo deste trabalho é revisar o processo de luteólise em bovinos.

Luteolisys is known as a process were the corpus luteum (CL) regresses, initially characterized by a decrease in progesterone (P4) plasmatic concentration. Luteolisys is very complex and involves many processes triggered through the lack of maternal recognition and rise of prostaglandin F2α (PGF2α) pulsate release. Increase of pulsatility is involve with ocitocine and estrogen endometrial receptors increase. When PGF2α high concentrations bind to CL receptor a series of changes in angiogenics and vasoactivs factores gene expression are triggered influencing direct or indirectly in CL. Modifications in genetic expression are required for further increase intraluteal PGF2α concentrations and consequently decrease P4 concentrations and regressing luteal tissue. This paper objective is to review bovine luteolisys.

Resumo

PURPOSE: To determine the effects of water-soluble derivative of green propolis in bladder cancer angiogenesis in rats given N-butyl-(-4-hydroxybutyl) nitrosamine (BBN). METHODS: Nine groups were established, where six of them (Groups 1 to 6), the animals received 0.05% BBN in their drinking water for 14 weeks. From the 32nd to the 40th week, Groups 1, 2, 3 and 4 were treated respectively with water, L-lysine (300 mg/kg/day), celecoxib (30 mg/kg/day) and propolis (300 mg/kg/day). Groups 5 and 6 were given propolis and L-lysine from the 1st to the 40th week (150 mg/kg/day). Microvascular density was determined by histological sections stained for the marker CD-31 and analyzed with specific software. RESULTS: The microvascular density in bladder carcinomas was lower (p<0.01) in rats receiving propolis than in controls given carcinogen only. On the other hand, the microvascular density of tumors in rats receiving carcinogen and L-lysine for 40 weeks from the beginning of carcinogen treatment was significantly higher (p<0.01) than in the corresponding controls. CONCLUSION: Water-soluble derivative of propolis inhibits angiogenesis in BBN-induced rat bladder cancer, while L-lysine treatment stimulates angiogenesis if initiated concurrently with BBN.

OBJETIVO: Determinar os efeitos da própolis verde solúvel em água na angiogênese de câncer de bexiga em ratos que receberam n-butil-(-4-hidroxibutil) nitrosamina (BBN). METODOS: Nove grupos foram estabelecidos, onde em seis destes (grupos de 1 a 6) os animais receberam BBN a 0,05% em água de beber por 14 semanas. Na 32ª semana das 40 semanas, os grupos 1, 2, 3 e 4 foram tratados respectivamente com água, L lisina (300 mg/kg/dia), celecoxibe (30 mg/kg/dia) e própolis (300 mg/kg/dia). Os grupos 5 e 6 receberam própolis e L lisina da 1ª a 40ª semana (150 mg/ kg/dia). A densidade microvascular foi determinada por cortes histológicos corados pelo CD-31 e analisados por programa de computador específico. RESULTADOS: A densidade microvascular em carcinomas de bexiga foi menor com p<0,01 nos ratos que receberam própolis do que nos carcinomas do grupo controle que recebeu apenas carcinógeno. Por outro lado, a densidade microvascular de tumores de ratos que receberam carcinógeno e L-Lisina por 40 semanas desde o início do carcinógeno foi significantemente maior com p<0,01 que a densidade microvascular dos tumores de seu respectivo grupo controle. CONCLUSÃO: A própolis verde solúvel em água inibiu a angiogênese em câncer de bexiga induzido pelo BBN, enquanto a L- lisina estimulou a angiogênese quando iniciada juntamente com o BBN.

Resumo

Molecular plant components have long been aimed at the angiogenesis and anti-angiogenesis pathways, and have been tested as sources for antineoplasic drugs with promising success. The present work deals with the anti-angiogenic effects of Methyl Jasmonate. Jasmonate derivatives were demonstrated to selectively damage the mitochondria of cancer cells. In vitro, 1-10 mM Methyl Jasmonate induced the cell death of the human umbilical vein endothelial cells (HUVEC) and the Murine melanoma cells (B16F10), while micromolar concentrations were ineffective. In vivo, comparable concentrations were toxic and reduced the vessel density of the Chorioallantoic Membrane of the Chicken Embryo (CAM). However, 1-10 µM concentrations produced a complex effect. There was increased capillary budding, but the new vessels were leakier and less organised than corresponding controls. It is suggested that not only direct toxicity, but also the drug effects upon angiogenesis are relevant to the antineoplasic effects of Methyl Jasmonate.

Moléculas de origem vegetal são, há muito, conhecidas como substâncias ativas sobre as vias de angiogênese e antiangiogênese e foram testadas como fonte de drogas antineoplásicas com sucesso promissor. Este trabalho trata dos efeitos antiangiogênicos do Metiljasmonato, um protótipo da família dos derivados do ácido jasmônico, que danificam seletivamente a mitocôndria de células neoplásicas. In vitro, metiljasmonato 1-10 mM promoveu a morte celular de células endoteliais humanas de cordão umbilical (HUVEC) e de melanoma murino (B16F10); concentrações micromolares foram inócuas. In vivo, concentrações equivalentes foram tóxicas e reduziram a densidade de vasos em membranas corioalantoicas de embrião de galinha (CAM). Entretanto, concentrações entre 1-10 µM produziram um efeito complexo. Ocorreu aumento no brotamento capilar, mas os novos vasos apresentaram-se frágeis e menos organizados que os controles correspondentes. Sugere-se que, além da toxicidade direta contra as células tumorais, a ação do metiljasmonato sobre a angiogênese seja relevante para seu efeito antineoplásico.

Resumo

PURPOSE: Thalidomide, because of its anti-inflammatory properties, as re-emerged as an option for the treatment of Crohn's disease refractory to standard therapy. We studied the effect of thalidomide on the healing of colonic anastomosis. METHODS: Sixty male rats (Rattus norvegicus), were divided into 3 groups of 20 animals each, respectively receiving 0.5 or 1.0 mg/kg thalidomide by the oral route for 7 days, or saline solution (control). All animals were submitted to continuous end-to-end anastomosis with 6-0 Prolene sutures. After sacrifice the anastomoses were analyzed macroscopically and submitted to determination of hydroxyproline, to histology and to immunohistochemistry for metalloproteinase 1, metalloproteinase 1 inhibitor and vascular endothelial growth factor (VEGF). RESULTS: Statistical analysis of the data showed no significant difference in macroscopic aspect or hydroxyproline determination (p= 0.5403). In the immunohistochemical analysis, the following p values were obtained: p = 0.5817 for VEGF, p = 0.1854 for metalloproteinase 1, and p = 0.0023 for metalloproteinase 1 inhibitor, with this last value being considered statistically significant. CONCLUSION: We conclude that thalidomide influenced collagen maturation. There was a stronger action of metalloproteinases, possibly indicating a negative tendency for the healing process.

OBJETIVO: Sabe-se que agentes farmacológicos podem influenciar no processo de cicatrização. A talidomida, devido às suas propriedades antiinflamatórias, tem ressurgido como uma opção no tratamento da doença de Crõhn refratária à terapêutica convencional. Neste trabalho, estudamos o efeito da talidomida na cicatrização de anastomoses colônicas no rato. MÉTODOS: Foram utilizados 60 animais Rattus norvegius, com peso médio de 300g. Organizou-se 3 grupos de 20 animais, sendo um grupo controle (AC), um grupo (BD), com administração de talidomida 0,5 mg/kg por 7 dias e um grupo (AD) com administração de talidomida 1,0 mg/kg por 7 dias. Foi realizada anastomose término-terminal contínua de prolene 6-0. O sacrifício foi no 7º. dia pós operatório e as anastomoses foram analisadas quanto a aspecto macroscópico, dosagem de hidroxiprolina, histologia em hematoxilina-eosina e imuno-histoquímica para metaloproteinase 1, inibidor de metaloproteinase 1 e VEGF. RESULTADOS: Não houve diferença estatisticamente significante para a observação macroscópica e para dosagem de hidroxiprolina (p=0,5403). Na análise imunohistoquímica, para VEGF houve p=0,5817, para metaloproteinase 1, p=0,1854 e para inibidor de metaloproteinase, p=0,0023, considerado estatisticamente significante. CONCLUSÃO: Concluímos que a talidomida influenciou na maturação do colágeno. Notou-se maior ação das metaloproteinases, que pode significar uma tendência negativa para o processo cicatricial.