In vivo antischistosomal efficacy of Porcelia ponderosa γ-lactones.

BACKGROUND: Schistosomiasis, caused by the parasitic blood fluke Schistosoma mansoni, is a significant global health concern, particularly in tropical and subtropical regions. The available chemotherapeutic drug is restricted to praziquantel with present problems related to efficacy, toxicity and resistance, justifying the search for new drugs. Different natural products, including γ-lactones, have demonstrated anthelmintic activity. Thus, in this study, new γ-lactones from Porcelia ponderosa were investigated for their anti-S. mansoni effects in vitro and in vivo. PURPOSE: To evaluate the therapeutical potential against S. mansoni of the mixture of γ-lactones 1 + 2 obtained from Porcelia ponderosa seeds. STUDY DESIGN AND METHODS: The precipitate formed during the concentration of CH2Cl2 extract from seeds of P. ponderosa showed to be composed by a mixture of the new γ-lactones 1 + 2 (in a ratio 77:23) which were chemically characterized using NMR and ESI-HRMS. This mixture was evaluated in vitro and in vivo against S. mansoni, using a murine model of schistosomiasis. Additionally, toxicity of the mixture of 1 + 2 (77:23) was determined using mammalian cell lines (in vitro) or the model organism Caenorhabditis elegans (in vivo). RESULTS: Seeds of P. ponderosa afforded a mixture of two unreported γ-lactones, 3­hydroxy-4-methylene-2-(tetracosa-17'Z,23'-diene-13',15'-diynyl)­but-2-enolide (1) and 3­hydroxy-4-methylene-2-(tetracos-17'Z-ene-13',15'-diynyl)­but-2-enolide (2). Initially, the antischistosomal activity of the mixture of 1 + 2 (77:23) was investigated in vitro, and obtained results demonstrate reduced activity against Schistosoma mansoni worms (EC50 of 83.3 µg/ml) in comparison to positive control praziquantel (EC50 of 1.5 µg/ml). However, when tested in vivo using oral administration at 400 mg kg-1, the standard dose used in the murine model of schistosomiasis, the mixture of 1 + 2 (77:23) revealed expressive reductions in both worm burden (65.7 %) and egg production (97.2 %), similar of those observed to praziquantel (89.7 % and 91.5 %, respectively). On the other hand, when treated using 200 and 100 mg kg-1, reductions in worm burden (25.7 and 12.4 %) and egg production (33.6 and 13.3 %) were also observed. Importantly, the mixture of 1 + 2 (77:23) exhibited no toxicity using mammalian cell lines (in vitro) or C. elegans (in vivo). CONCLUSION: Considering the promising in vivo activity of γ-lactones from P. ponderosa, the mixture of 1 + 2 (77:23) can be considered as promising candidate for the development of novel antischistosomal therapeutics, underscoring the importance of biodiversity exploration in the search for effective treatments against neglected tropical diseases.

Anatomopathological changes in laying quails.

The objective of the current study was to carry out a survey of the main anatomopathological alterations in raising quails and evaluate possible interference of these in the bone tissue. To obtain the data, 23 quails were collected from farm in the central Serrana region of Espírito Santo. Necropsies with macroscopic descriptions, microbiological, coproparasitological, radiographic and histomorphometric tests were carried out. It was done data descriptive analysis and average comparision using Student T test. It was found that they presented lesions predominantly in the digestive system, followed by urinary and reproductive, and muscular system, were the altered color of the liver (47%) was the most frequent lesion. In the parasitological exams, it was found oocysts of Eimeira sp. (39.13%). In the microbiological exams, it was detected predominantly Escherichia coli (83%). Moderate osteopenia in quails, but the percentage of trabecular bone on bones was similar between healthy and diseased quails, without bone changes in histology. Microscopically, it was observed lung congestion as predominant lesion. It is concluded that there was predominance of alterations in the digestive system and mild parasitic infection; and although there was moderate level of osteopenia, there wasn't bone change as a result of the observed infections.

Microbial metabolic activity in Amazon floodplain forest and agricultural soils.

Microorganisms play an essential role in ecosystem functions. An increasingly used method for conducting functional analyses of a soil microbial community is based on the physiological profile at the community level. This method allows the metabolic capacity of microorganisms to be assessed based on patterns of carbon consumption and derived indices. In the present study, the functional diversity of microbial communities was assessed in soils from seasonally flooded-forest (FOR) and -traditional farming systems (TFS) in Amazonian floodplains flooded with black, clear, and white water. The soils of the Amazon floodplains showed differences in the metabolic activity of their microbial communities, with a general trend in activity level of clear water floodplain > black water floodplain > white water floodplain. The redundancy analysis (RDA) indicated that soil moisture (flood pulse) was the most important environmental parameter in determining the metabolic activity of the soil microbial communities in the black, clear, and white floodplains. In addition, the variance partitioning analysis (VPA) indicated that the microbial metabolic activity of the soil was more influenced by water type (41.72%) than by seasonality (19.55%) and land use type (15.28%). The soil microbiota of the white water floodplain was different from that of the clear water and black water floodplains in terms of metabolic richness, as the white water floodplain was mainly influenced by the low substrate use during the non-flooded period. Taken together, the results show the importance of considering soils under the influence of flood pulses, water types, and land use as environmental factors when recognizing functional diversity and ecosystem functioning in Amazonian floodplains.

Understanding ayahuasca effects in major depressive disorder treatment through in vitro metabolomics and bioinformatics.

Emerging insights from metabolomic-based studies of major depression disorder (MDD) are mainly related to biochemical processes such as energy or oxidative stress, in addition to neurotransmission linked to specific metabolite intermediates. Hub metabolites represent nodes in the biochemical network playing a critical role in integrating the information flow in cells between metabolism and signaling pathways. Limited technical-scientific studies have been conducted to understand the effects of ayahuasca (Aya) administration in the metabolism considering MDD molecular context. Therefore, this work aims to investigate an in vitro primary astrocyte model by untargeted metabolomics of two cellular subfractions: secretome and intracellular content after pre-defined Aya treatments, based on DMT concentration. Mass spectrometry (MS)-based metabolomics data revealed significant hub metabolites, which were used to predict biochemical pathway alterations. Branched-chain amino acid (BCAA) metabolism, and vitamin B6 and B3 metabolism were associated to Aya treatment, as "housekeeping" pathways. Dopamine synthesis was overrepresented in the network results when considering the lowest tested DMT concentration (1 µmol L-1). Building reaction networks containing significant and differential metabolites, such as nicotinamide, L-DOPA, and L-leucine, is a useful approach to guide on dose decision and pathway selection in further analytical and molecular studies.

Physiological and Molecular Responses of Woody Plants Exposed to Future Atmospheric CO2 Levels under Abiotic Stresses.

Climate change is mainly driven by the accumulation of carbon dioxide (CO2) in the atmosphere in the last century. Plant growth is constantly challenged by environmental fluctuations including heat waves, severe drought and salinity, along with ozone accumulation in the atmosphere. Food security is at risk in an increasing world population, and it is necessary to face the current and the expected effects of global warming. The effects of the predicted environment scenario of elevated CO2 concentration (e[CO2]) and more severe abiotic stresses have been scarcely investigated in woody plants, and an integrated view involving physiological, biochemical and molecular data is missing. This review highlights the effects of elevated CO2 in the metabolism of woody plants and the main findings of its interaction with abiotic stresses, including a molecular point of view, aiming to improve the understanding of how woody plants will face the predicted environmental conditions. Overall, e[CO2] stimulates photosynthesis and growth and attenuates mild to moderate abiotic stress in woody plants if root growth and nutrients are not limited. Moreover, e[CO2] does not induce acclimation in most tree species. Some high-throughput analyses involving omics techniques were conducted to better understand how these processes are regulated. Finally, knowledge gaps in the understanding of how the predicted climate condition will affect woody plant metabolism were identified, with the aim of improving the growth and production of this plant species.

Grapiprant or carprofen following ovariohysterectomy in the cat: analgesic efficacy, hematological, biochemical and urinalysis evaluation.

OBJECTIVES: This study aimed to compare the analgesic effect between carprofen and grapiprant every 12 or 24 h on postoperative pain in cats undergoing ovariohysterectomy, in addition to the effects on the hematological, biochemical and urinalysis variables. METHODS: A total of 32 female cats were randomly divided into three groups, according to the treatment administered with the first dose given orally 90 mins before surgery, as follows: CAR (cats received 4 mg/kg carprofen, n = 11); GRA1 (cats received 2 mg/kg grapiprant, n = 10); and GRA2 (cats received 2 mg/kg grapiprant q12h, n = 11). Pain was assessed by UNESP-Botucatu Multidimensional Composite Pain Scale (UNESP) and Glasgow Feline Composite Measure Pain Scale (GLASGOW) for cats preoperatively (baseline) and at 1, 3, 6, 8, 12 and 24 h after extubation. Venous blood was collected at baseline, and 12 and 24 h after the administration of carprofen or grapiprant to perform a complete blood count (CBC), the percentage of Heinz bodies and serum biochemistry (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyltransferase, creatinine and urea). Urinalysis was performed at baseline and 24 h after extubation. Glucose levels were evaluated at baseline and 1 h postoperatively. RESULTS: Pain scores were not significantly different among groups in both scales, although pain was higher at 3 h in comparison with 24 h in all groups. In the GRA1 and GRA2 groups, 67% (14/21) of cats needed rescue analgesia compared with 18% (2/11) in the CAR group. Glucose increased from baseline to 1 h in the GRA1 and GRA2 groups. None of the CBC, serum biochemistry and urinalysis variables differed among groups. CONCLUSIONS AND RELEVANCE: Grapiprant did not promote adequate analgesia during the first 3 h postoperatively in cats undergoing ovariohysterectomy compared with carprofen, and no benefits were observed by administering grapiprant every 12 h.

Antileishmanial Effects of Acetylene Acetogenins from Seeds of Porcelia macrocarpa (Warm.) R.E. Fries (Annonaceae) and Semisynthetic Derivatives.

As part of our continuous studies involving the prospection of natural products from Brazilian flora aiming at the discovery of prototypes for the development of new antiparasitic drugs, the present study describes the isolation of two natural acetylene acetogenins, (2S,3R,4R)-3-hydroxy-4-methyl-2-(n-eicos-11'-yn-19'-enyl)butanolide (1) and (2S,3R,4R)-3-hydroxy-4-methyl-2-(n-eicos-11'-ynyl)butanolide (2), from the seeds of Porcelia macrocarpa (Warm.) R.E. Fries (Annonaceae). Using an ex-vivo assay, compound 1 showed an IC50 value of 29.9 µM against the intracellular amastigote forms of Leishmania (L.) infantum, whereas compound 2 was inactive. These results suggested that the terminal double bond plays an important role in the activity. This effect was also observed for the semisynthetic acetylated (1a and 2a) and eliminated (1b and 2b) derivatives, since only compounds containing a double bond at C-19 displayed activity, resulting in IC50 values of 43.3 µM (1a) and 23.1 µM (1b). In order to evaluate the effect of the triple bond in the antileishmanial potential, the mixture of compounds 1 + 2 was subjected to catalytic hydrogenation to afford a compound 3 containing a saturated side chain. The antiparasitic assays performed with compound 3, acetylated (3a), and eliminated (3b) derivatives confirmed the lack of activity. Furthermore, an in-silico study using the SwissADME online platform was performed to bioactive compounds 1, 1a, and 1b in order to investigate their physicochemical parameters, pharmacokinetics, and drug-likeness. Despite the reduced effect against amastigote forms of the parasite to the purified compounds, different mixtures of compounds 1 + 2, 1a + 2a, and 1b + 2b were prepared and exhibited IC50 values ranging from 7.9 to 38.4 µM, with no toxicity for NCTC mammalian cells (CC50 > 200 µM). Selectivity indexes to these mixtures ranged from >5.2 to >25.3. The obtained results indicate that seeds of Porcelia macrocarpa are a promising source of interesting prototypes for further modifications aiming at the discovery of new antileishmanial drugs.

Micro-Raman spectroscopy of lipid halo and dense-core amyloid plaques: aging process characterization in the Alzheimer's disease APPswePS1ΔE9 mouse model.

The deposition of amyloid plaques is considered one of the main microscopic features of Alzheimer's disease (AD). Since plaque formation can precede extensive neurodegeneration and it is the main clinical manifestation of AD, it constitutes a relevant target for new treatment and diagnostic approaches. Micro-Raman spectroscopy, a label-free technique, is an accurate method for amyloid plaque identification and characterization. Here, we present a high spatial resolution micro-Raman hyperspectral study in transgenic APPswePS1ΔE9 mouse brains, showing details of AD tissue biochemical and histological changes without staining. First we used stimulated micro-Raman scattering to identify the lipid-rich halo surrounding the amyloid plaque, and then proceeded with spontaneous (conventional) micro-Raman spectral mapping, which shows a cholesterol and sphingomyelin lipid-rich halo structure around dense-core amyloid plaques. The detailed images of this lipid halo relate morphologically well with dystrophic neurites surrounding plaques. Principal Component Analysis (PCA) of the micro-Raman hyperspectral data indicates the feasibility of the optical biomarkers of AD progression with the potential for discriminating transgenic groups of young adult mice (6-month-old) from older ones (12-month-old). Frequency-specific PCA suggests that plaque-related neurodegeneration is the predominant change captured by Raman spectroscopy, and the main differences are highlighted by vibrational modes associated with cholesterol located majorly in the lipid halo.

Nonlinear and vibrational microscopy for label-free characterization of amyloid-ß plaques in Alzheimer's disease model.

Given the long subclinical stage of Alzheimer's disease (AD), the study of biomarkers is relevant both for early diagnosis and the fundamental understanding of the pathophysiology of AD. Biomarkers provided by Amyloid-ß (Aß) plaques have led to an increasing interest in characterizing this hallmark of AD due to its promising potential. In this work, we characterize Aß plaques by label-free multimodal imaging: we combine two-photon excitation autofluorescence (TPEA), second harmonic generation (SHG), spontaneous Raman scattering (SpRS), coherent anti-Stokes Raman scattering (CARS), and stimulated Raman scattering (SRS) to describe and compare high-resolution images of Aß plaques in brain tissues of an AD mouse model. Comparing single-laser techniques images, we discuss the origin of the SHG, which can be used to locate the plaque core reliably. We study both the core and the halo with vibrational microscopy and compare SpRS and SRS microscopies for different frequencies. We also combine SpRS spectroscopy with SRS microscopy and present two core biomarkers unexplored with SRS microscopy: phenylalanine and amide B. We provide high-resolution SRS images with the spatial distribution of these biomarkers in the plaque and compared them with images of the amide I distribution. The obtained spatial correlation corroborates the feasibility of these biomarkers in the study of Aß plaques. Furthermore, since amide B enables rapid imaging, we discuss its potential as a novel fingerprint for diagnostic applications.

Lipotoxicity-associated inflammation is prevented by guarana (Paullinia cupana) in a model of hyperlipidemia.

Hyperlipidemia causes lipotoxicity which prompts an inflammatory response linked to the development of cardiovascular diseases. Natural compounds have been receiving special attention for its potential to treat diseases, inexpensiveness, and safety. Guarana (Paullinia cupana) has demonstrated notable anti-inflammatory and antioxidant effects, which may prevent chronic diseases caused by changes in lipid profile. Thus, this study aims to evaluate the effect of guarana powder (Paullinia cupana) in the purine metabolism and inflammatory profile in lymphocytes and serum of rats with Poloxamer-407-induced hyperlipidemia. Pretreatment with guarana 12.5, 25, and 50 mg/kg/day or caffeine (0.2 mg/kg/day) by gavage was applied to adult male Wistar rats for a period of 30 days. As a comparative standard, we used simvastatin (0.04 mg/kg) post-induction. Hyperlipidemia was acutely induced with intraperitoneally injection of Poloxamer-407 (500 mg/kg). Guarana powder and caffeine increased the activity of the E-NTPDase (ecto-apyrase), and all pretreatments decreased the E-ADA (ecto-adenosine deaminase) activity, reducing the inflammatory process caused by lipotoxicity. In hyperlipidemic rats, ATP levels were increased while adenosine levels were decreased, guarana and caffeine reverted these changes. Guarana powder, caffeine, and simvastatin also prevented the increase in INF-γ and potentiated the increase in IL-4 levels, promoting an anti-inflammatory profile. Guarana promoted a more robust effect than caffeine. Our results show that guarana powder and caffeine have an anti-inflammatory as seen by the shift from a proinflammatory to an anti-inflammatory profile. The effects of guarana were more pronounced, suggesting that guarana powder may be used as a complementary therapy to improve the lipotoxicity-associated inflammation.

Assessment of Ecological Risk and Environmental Behavior of Pesticides in Environmental Compartments of the Formoso River in Tocantins, Brazil.

Anthropogenic interference the ecosystem unavoidably changes the physical and biological environment. The biodiversity of the Amazon region has been threatened by increased agricultural production and pesticide use. Considering that monitoring pesticides in environments close to their application is one of the ways to preserve the ecosystem, this study investigated the levels of pesticide residues in different environmental compartments (soil, sediment, and water samples). Thirty-one active ingredients of pesticides of different classes were analyzed by UHPLC-MS/MS. For this purpose, we performed quarterly collections in dry and rainy seasons in the region, which helped to evaluate the impact of pesticides on the biodiversity of the study site. Sampling points were the river banks in the area of an agricultural project in Formoso do Araguaia city, Tocantins State. After analysis, we detected the following substances in the water matrix: clomazone, fluazifop-p-butyl, flutolanil, metsulfuron-methyl, propanil, and imidacloprid. Nevertheless, we did not detect any active ingredient in sediment and soil matrices. The active ingredient clomazone was present in all points in the trials, with concentrations reaching up to 0.538 µg L-1. These substances have potential for groundwater contamination. Even at low concentrations in the aquatic ecosystem, these substances can damage human populations and wildlife species, given their toxicological classification. Thus, the study showed an environmental risk of bioaccumulation and/or biomagnification in the region, which may affect environmental biodiversity as well as human health.

A fingerprint of amyloid plaques in a bitransgenic animal model of Alzheimer's disease obtained by statistical unmixing analysis of hyperspectral Raman data.

The global prevalence of Alzheimer's disease (AD) points to endemic levels, especially considering the increase of average life expectancy worldwide. AD diagnosis based on early biomarkers and better knowledge of related pathophysiology are both crucial in the search for medical interventions that are able to modify AD progression. In this study we used unsupervised spectral unmixing statistical techniques to identify the vibrational spectral signature of amyloid ß aggregation in neural tissues, as early biomarkers of AD in an animal model. We analyzed spectral images composed of a total of 55 051 Raman spectra obtained from the frontal cortex and hippocampus of five bitransgenic APPswePS1ΔE9 mice, and colocalized amyloid ß plaques by other fluorescence techniques. The Raman signatures provided a multifrequency fingerprint consistent with the results of synthesized amyloid ß fibrils. The fingerprint obtained from unmixed analysis in neural tissues is shown to provide a detailed image of amyloid plaques in the brain, with the potential to be used as biomarkers for non-invasive early diagnosis and pathophysiology studies in AD on the retina.

Antitrypanosomal Activity of Acetogenins Isolated from the Seeds of Porcelia macrocarpa Is Associated with Alterations in Both Plasma Membrane Electric Potential and Mitochondrial Membrane Potential.

As part of a drug discovery program aimed at the identification of anti- Trypanosoma cruzi metabolites from Brazilian flora, four acetogenins (1-4) were isolated from the seeds of Porcelia macrocarpa and were identified by NMR spectroscopy and HRESIMS. The new compounds 1 and 2 displayed activity against the trypomastigote (IC50 = 0.4 and 3.6 µM) and amastigote (IC50 = 23.0 and 27.7 µM) forms. The structurally related known compound 3 showed less potency to the amastigotes, with an IC50 value of 58 µM, while the known compound 4 was inactive. To evaluate the potential mechanisms for parasite death, parameters were evaluated by fluorometric assays: (i) plasma membrane permeability, (ii) plasma membrane electric potential (ΔΨp), (iii) reactive oxygen species production, and (iv) mitochondrial membrane potential (ΔΨm). The results obtained indicated that compounds 1 and 2 depolarize plasma membranes, affecting ΔΨp and ΔΨm and contributing to the observed cellular damage and disturbing the bioenergetic system. In silico studies of pharmacokinetics and toxicity (ADMET) properties predicted that all compounds were nonmutagenic, noncarcinogenic, nongenotoxic, and weak hERG blockers. Additionally, none of the isolated acetogenins 1-4 were predicted as pan-assay interference compounds.

A diferença de idade é um fator determinante na modulação do estresse oxidativo muscular induzido pelo exercício agudo

Resumo Este estudo teve por objetivo comparar os efeitos do exercício agudo com carga de trabalho relativa em gastrocnêmio de ratos Wistar com três e 18 meses. Os animais foram divididos em quatro grupos (n = 6): controle de três e 18 meses; exercício de três e 18 meses. Os grupos exercitados foram submetidos a uma única sessão de corrida na esteira com 60 minutos em velocidade de 0,8 km/h e 1,2 km/h. Foram analisados parâmetros do metabolismo (níveis de lactato, conteúdo de glicogênio, níveis de succinato desidrogenase, citocromo c oxidase e de estresse oxidativo (SOD, CAT e GPX). Os resultados mostraram um aumento nos marcadores metabólicos após o exercício agudo independentemente da idade dos animais e similaridade nos danos oxidativos apesar de as enzimas antioxidantes apresentarem modulação diferenciada nos animais mais velhos em comparação com animais jovens.

Abstract The effects of exercise on the generation of reactive oxygen species and the response to muscle oxidative stress determines longevity. This study compares the effects of acute exercise with similar relative workload in rats with 3 and 18 months. The animals were divided into four groups (n = 6): control 3-months; exercise 3-months; control 18-months and exercise 18-months. Exercised groups underwent to a single bout of running with 60 minutes in the speed 0.8 km/h (18 months) and 1.2 km/h (3 months). Metabolic parameters (lactate levels, glycogen content, succinate dehydrogenase levels, cytochrome c oxidase) and oxidative stress (activity of superoxide dismutase, catalase and glutathione peroxidase). The results showed an increase in metabolic markers after acute exercise regardless of the age and similarity in oxidative damage even if the antioxidant enzymes are age-dependent. These results suggest that the effects of acute exercise at moderate intensity, affects the metabolism independent of age, and, that the differential response in enzymatic antioxidant system between groups do not promote protection against oxidative damage.

Este estudio ha tenido como objetivo comparar los efectos del ejercicio agudo con carga de trabajo relativamente similar en el gastrocnemio de ratas Wistar con 3 y 8 meses. Se separó a los animales en cuatro grupos (n = 6): control de 3 y 18 meses, y ejercicio de 3 y 18 meses. Se sometió a los grupos de ejercicio a una sola sesión de carrera en la cinta durante 60 minutos con una velocidad de 0,8 km/h y 1,2 km/h. Se analizaron algunos parámetros del metabolismo (niveles de lactato, contenido de glucógeno, niveles de succionato-deshidrogenasa, citocromo c-oxidasa e de estrés oxidativo [superóxido-dismutasa, catalasa y glutatión-peroxidasa]). Los resultados mostraron un aumento de los marcadores metabólicos después del ejercicio agudo independientemente de la edad de los animales y la similitud de los daños oxidativos aunque las enzimas antioxidantes presentan modulación diferenciada en animales viejos en comparación con animales jóvenes.

Linfonodo axilar como sentinela de neoplasia mamária em cadelas / Axillary lymph node as sentinel for mammary neoplasia in bitches

Linfonodo axilar como sentinela de neoplasia mamária em cadelas. O estudo dos tumores de mama em cadelas é de grande importância devido à alta frequência com que surgem na clínica de pequenos animais. O presente estudo teve como objetivo avaliar a importância do linfonodo axilar como sentinela em neoplasias mamárias de cadelas. Foram avaliadas 49 fêmeas com neoplasia mamária, submetidas à mastectomia unilateral total, utilizando o corante azul patente para a identificação do linfonodo axilar, o qual foi submetido à análise histopatológica com a coloração de hematoxilina-eosina e imuno-histoquímica (IHQ) com anticorpo citoqueratina (AE1/AE3) para procura de metástase. Oito cadelas apresentaram metástases em linfonodo axilar, sendo sete detectadas por histopatologia e por IHQ e uma somente pela IHQ (micrometástase). Uma paciente que apresentava tumor em mamas abdominal caudal e inguinal tinha metástase no linfonodo axilar e inguinal. Assim, observa-se que o tumor pode causar alteração na drenagem linfática provocando metástase em linfonodos que normalmente não drenam determinadas mamas, por isso a retirada do linfonodo axilar deve ser incluída como técnica de rotina para permitir melhor estadiamento das neoplasias mamárias de cadelas.(AU)

Mammary tumors research in bitches is important due to their high incidence. The aim of this study was to evaluate the importance of the axillary lymph node as a sentinel lymph node for mammary neoplasms in female dogs. Forty-nine bitches with mammary neoplasia were submitted to total unilateral mastectomy, and the axillary lymph node was identified using the patent blue dye. This lymph node was processed routinely for histopathological analysis and stained with hematoxylin-eosin and by immunohistochemistry (IHC) with cytokeratin antibody (AE1/AE3) to search for metastasis. Eight dogs had axillary lymph node metastases, seven of which were detected by histopathology and by IHC and only one by IHC (micrometastasis). One dog who presented tumor in caudal and inguinal abdominal mammary glands had metastases in the axillary and inguinal lymph nodes. It is concluded that the mammary tumor can cause alteration in lymphatic drainage leading to metastases in lymph nodes which normally do not drain certain glands; so the removal of the axillary lymph node should be included as a routine technique to allow better staging of mammary neoplasms of bitches.(AU)

Linfonodo axilar como sentinela de neoplasia mamária em cadelas / Axillary lymph node as sentinel for mammary neoplasia in bitches

Linfonodo axilar como sentinela de neoplasia mamária em cadelas. O estudo dos tumores de mama em cadelas é de grande importância devido à alta frequência com que surgem na clínica de pequenos animais. O presente estudo teve como objetivo avaliar a importância do linfonodo axilar como sentinela em neoplasias mamárias de cadelas. Foram avaliadas 49 fêmeas com neoplasia mamária, submetidas à mastectomia unilateral total, utilizando o corante azul patente para a identificação do linfonodo axilar, o qual foi submetido à análise histopatológica com a coloração de hematoxilina-eosina e imuno-histoquímica (IHQ) com anticorpo citoqueratina (AE1/AE3) para procura de metástase. Oito cadelas apresentaram metástases em linfonodo axilar, sendo sete detectadas por histopatologia e por IHQ e uma somente pela IHQ (micrometástase). Uma paciente que apresentava tumor em mamas abdominal caudal e inguinal tinha metástase no linfonodo axilar e inguinal. Assim, observa-se que o tumor pode causar alteração na drenagem linfática provocando metástase em linfonodos que normalmente não drenam determinadas mamas, por isso a retirada do linfonodo axilar deve ser incluída como técnica de rotina para permitir melhor estadiamento das neoplasias mamárias de cadelas.(AU)

Mammary tumors research in bitches is important due to their high incidence. The aim of this study was to evaluate the importance of the axillary lymph node as a sentinel lymph node for mammary neoplasms in female dogs. Forty-nine bitches with mammary neoplasia were submitted to total unilateral mastectomy, and the axillary lymph node was identified using the patent blue dye. This lymph node was processed routinely for histopathological analysis and stained with hematoxylin-eosin and by immunohistochemistry (IHC) with cytokeratin antibody (AE1/AE3) to search for metastasis. Eight dogs had axillary lymph node metastases, seven of which were detected by histopathology and by IHC and only one by IHC (micrometastasis). One dog who presented tumor in caudal and inguinal abdominal mammary glands had metastases in the axillary and inguinal lymph nodes. It is concluded that the mammary tumor can cause alteration in lymphatic drainage leading to metastases in lymph nodes which normally do not drain certain glands; so the removal of the axillary lymph node should be included as a routine technique to allow better staging of mammary neoplasms of bitches.(AU)

Nucleotide and nucleoside involvement in immunomodulation in experimental Chagas disease.

The aim of this study was to evaluate whether Trypanosma cruzi infections cause alterations in the levels of seric purines, which could contribute to host immunomodulation. Twelve mice were divided into two groups identified as control (uninfected) and infected (T. cruzi) groups. The influence of the disease on seric purine levels was verified on day 20 post-infection (PI) by HPLC. Infected mice had circulating trypomastigotes during the experiment, as well as amastigote forms in the heart associated with inflammatory infiltrates. Increases on adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine (ADO), inosine (INO), and uric acid (URIC) levels were observed in the infected animals, while the adenosine monophosphate (AMP) and xanthine (XAN) levels were reduced compared with mice of the control group, indicating a possible impairment on the purinergic system, and consequently, on the immune system during the clinical course of the disease. In summary, the T. cruzi infection alters the seric purine levels, and consequently, modulates the immune system.

Structural Changes in Stx1 Engineering Monoclonal Antibody Improves Its Functionality as Diagnostic Tool for a Rapid Latex Agglutination Test.

Stx1 toxin is one of the AB5 toxins of Shiga toxin-producing Escherichia coli (STEC) responsible for foodborne intoxication during outbreaks. The single-chain variable fragment (scFv) is the most common recombinant antibody format; it consists of both variable chains connected by a peptide linker with conserved specificity and affinity for antigen. The drawbacks of scFv production in bacteria are the heterologous expression, conformation and stability of the molecule, which could change the affinity for the antigen. In this work, we obtained a stable and functional scFv-Stx1 in bacteria, starting from IgG produced by hybridoma cells. After structural modifications, i.e., change in protein orientation, vector and linker, its solubility for expression in bacteria was increased as well as the affinity for its antigen, demonstrated by a scFv dissociation constant (KD) of 2.26 × 10-7 M. Also, it was able to recognize purified Stx1 and cross-reacted with Stx2 toxin by ELISA (Enzyme-Linked Immunosorbent Assay), and detected 88% of Stx1-producing strains using a rapid latex agglutination test. Thus, the scFv fragment obtained in the present work is a bacteria-produced tool for use in a rapid diagnosis test, providing an alternative for STEC diagnosis.