RESUMO

A simple method set for assessing biochemical changes associated with osmotic stress responses was developed using coffee (Coffea arabica L.) leaf disks. Stress was induced by polyethylene glycol (PEG) exposure. Quantitative evaluation of tissue physiological stress parameters was carried out using analytical methods to validate the conversion of classic qualitative histochemical tests for localizing lipid peroxidation, hydrogen peroxide, and total xanthine alkaloids into semi-quantitative assays. Relative electrolyte leakage (EL%) and chlorophyll content (SPAD index) were also recorded. EL% levels of treated disks were higher than those of control ones, whereas SPAD indexes were comparable. Histochemical localization indicated that levels of lipid peroxidation, H2O2, and total xanthines were also higher under osmotic stress than in control conditions. Semi-quantitative data obtained by image processing of histochemical staining consistently matched quantitative evaluations. Chromatographic analyses revealed that theophylline and caffeine concentrations increased in the presence of PEG, whereas theobromine remained constant in relation to the control. The methods herein described can be useful to rapidly acquire initial data regarding biochemical osmotic stress responses in coffee tissues based on simple staining and imaging steps. Moreover, it is likely that the same method may be applicable to other types of stresses and plant species upon minor adjustments.

Assuntos

RESUMO

The prostate undergoes normal or pathological morphological changes throughout life. An understanding of these changes is fundamental for the comprehension of aging-related pathological processes such as benign prostatic hyperplasia (BPH) and cancer. In the present study, we show some of these morphological changes, as well as histochemical techniques like Weigert's resorcin-fuchsin method, Picrosirius Red, and Gömöri's reticulin for use as tools in the study of prostate tissue under light microscopy. For this purpose, prostates of the Mongolian gerbil (n = 9), an experimental model that develops BPH spontaneously, were analyzed at three life stages: young (1 month old), adult (3 months old), and old (15 months old). The results showed that fibrillar components such as collagen, and reticular and elastic fibers, change throughout life. In young animals, the prostate has cuboidal epithelium surrounded by thin layers of smooth muscle, continuous collagen fibers, winding reticular fibers, and sporadic elastic fibers. With adulthood, the epithelium becomes columnar, encircled by compacted muscle cells among slender collagen fibers, elongated reticular fibers, and linear elastic fibers. In aging individuals, the prostate's epithelium stratifies, surrounded by thick muscle layers among dense collagen fibers, disordered reticular fibers, and elastic fibers in different planes. We also identified a few accumulations of lipid droplets and lipofuscin granules in adult animals and high accumulation in old animals evidenced by Oil red O and Gömöri-Halmi techniques, respectively. The histochemical techniques presented here have been demonstrated to be useful and accessible tools in prostate studies. RESEARCH HIGHLIGHTS: Cytochemical techniques to study prostate morphology. The prostate changes with age.

Assuntos

RESUMO

Myxoid endometriosis, a rare entity, is part of the histological changes that can occur in endometriosis. Pathologists must know the histological guidelines for the morphological recognition of this entity, as well as the histochemical and immunohistochemical techniques that support diagnosis, and define the morphological characteristics of myxoid endometriosis. In the present work, we propose diagnostic guidelines and primary differential diagnoses using special histochemical techniques and immunohistochemical reactions to recognize this entity.

RESUMO

ABSTRACT Canine distemper causes demyelinating leucoencephalitis, like human multiple sclerosis. The encephalic microenvironment, including the extracellular matrix, is an important key factor of this lesion, already described in multiple sclerosis but not proved in canine distemper. Thereby, the aim of this work is to characterize the extracellular matrix in the encephalon of dogs with canine distemper. Samples of cortex and cerebellum of 14 naturally infected dogs with canine distemper virus were collected after being sent for necropsy in the Animal Pathology Laboratory of the Veterinary Hospital of Uberlândia Federal University. The samples were processed as routine, stained with Hematoxylin and Eosin (H.E), Masson Trichrome (MT), Periodic Acid-Schiff (PAS) and Reticulin, and then described. Areas of demyelination and necrosis were quantified in percentage of stain. The TM samples showed blue stain around vessels and meninge, which indicates a higher deposition of collagen in lesioned areas. At necrotic areas, reticulin stain pointed to a disorganization in the vascular wall and PAS-stained pink granules in macrophages. We conclude that the extracellular matrix seems to participate in the pathogeny of canine distemper. More research should be done to better detail the involvement of these molecules in the course of this disease.

RESUMO A cinomose canina, assim como a esclerose múltipla, provoca leucoencefalite desmeilinizante. O microambiente encefálico, incluindo a matriz extracelular, atua como fator adjuvante na esclerose múltipla, porém não há comprovação do mesmo na cinomose canina. Portanto o objetivo neste trabalho é caracterizar a matriz extracelular do encéfalo de cães com cinomose canina. Foram coletados fragmentos de córtex frontal e cerebelo de 14 cães naturalmente infectados com cinomose canina encaminhados para necropsia no Laboratório de Patologia Animal do Hospital Veterinário da Universidade Federal de Uberlândia. Os fragmentos foram processados rotineiramente, corados com Hematoxilina e Eosina (H.E.), Tricrômico de Masson (TM), Ácido-Periódico de Schiff (PAS) e Reticulina e então foram descritas. As áreas com desmielinização e/ou necrose também foram quantificadas. A coloração de TM evidenciou marcação azulada em vasos e meninge, indicando maior deposição de fibras colágenas nas lesões. Nas áreas de necrose notou-se parede vascular desorganizada, a partir da reticulina, além de pigmentos róseos em macrófagos corados com PAS. Conclui-se que a matriz extracelular aparenta participar na patogenia da cinomose. Outros estudos são necessários para maiores detalhes da ação dessas moléculas na patogenia da cinomose canina.

RESUMO

Odonata species live through their immature development in aquatic habitats, where the eggs are adapted to survive the initial stages. The survival of the eggs is linked to the layers that make up the eggshell. These layers are common to all odonate species, but show variations among them, depending on the oviposition method. For example, endophytic eggs (laid in plant tissues) and exophytic eggs (laid on the water surface) have different morphologies, which may reveal egg adaptations to environmental conditions and stresses. The differences in the egg morphologies could be shown in the length of the egg layers, their histochemical composition, and in the ultrastructure. The histochemical composition can reveal several features that could lead us to a better understanding of its function, for example, how glycoproteins and total proteins could regulate the humidity and water retention in the eggs according to the environments in which the eggs are placed.

Assuntos

RESUMO

This work aimed to carry out phytochemical prospecting and evaluate the antioxidant potential of Diplopterys pubipetala, a species of Malpighiaceae family that has not yet been studied.In qualitative analyses of hydroethanolic extracts of leaves and stems were detected the presence of flavonoids, alkaloidsand terpenes. The histochemical evaluation evidenced a greater distribution of these compounds in the tissues of leaf when compared with those of stem. The analysis by mass spectrometry allowed the identification of prenylated xanthones and glycoside flavonoids that have not yet been reported in the literature. The antioxidant activity of the stem extract was considered moderate (IAA = 0.79), but the leaves presented a strong antioxidant activity (IAA = 1.6). In this work we present information about the phytochemicals of D. pubipetala, showing that the species is promising in obtaining compounds with medicinal potential mainly antioxidant potential.

Assuntos

RESUMO

ABSTRACT: Leishmania infantum causes canine leishmaniasis. Using parasitological and molecular analyses, we identified L. infantum in the reproductive organs of male and female dogs. Using histochemistry, immunohistochemistry, and PCR, we examined tissue samples from the reproductive organs of 8 male dogs and 16 female dogs diagnosed with leishmaniasis. Despite the absence of macroscopic or microscopic lesions in these organs, we observed L. infantum amastigotes in tissue samples from the testis and the uterus. PCR and sequencing of these tissues revealed sequences that matched 100% with L. infantum DNA available at GenBank. The presence of L. infantum amastigotes and DNA in testicular and uterine tissue samples suggested that these organs can harbor the parasite without associated macroscopic or microscopic lesions, and this can be especially important in the vertical and venereal transmission of leishmaniasis in dogs.

RESUMO: Leishmania infantum é agente etiológico da leishmaniose canina. Por meio de análises parasitológicas e moleculares, a presença do parasita foi investigada em órgãos reprodutivos de cães machos e fêmeas. Amostras de tecidos dos órgãos reprodutivos de 8 cães machos e 16 fêmeas diagnosticados com leishmaniose foram avaliadas por histoquímica, imunohistoquímica e PCR. Apesar de não terem sido observadas lesões macroscópicas ou microscópicas nos órgãos reprodutivos desses cães, formas amastigotas de L. infantum foram observadas em amostras teciduais do testículo e útero. A PCR e o sequenciamento do DNA extraído desses tecidos revelaram sequências 100% idênticas a L. infantum depositadas no GenBank. Nossos resultados sugerem que os testículos e o útero podem abrigar o parasita, sem associação com lesões macroscópicas ou microscópicas, o que pode ter uma grande importância na transmissão venérea e vertical da leishmaniose entre cães.

RESUMO

Leishmania infantum causes canine leishmaniasis. Using parasitological and molecular analyses, we identified L. infantum in the reproductive organs of male and female dogs. Using histochemistry, immunohistochemistry, and PCR, we examined tissue samples from the reproductive organs of 8 male dogs and 16 female dogs diagnosed with leishmaniasis. Despite the absence of macroscopic or microscopic lesions in these organs, we observed L. infantum amastigotes in tissue samples from the testis and the uterus. PCR and sequencing of these tissues revealed sequences that matched 100% with L. infantum DNA available at GenBank. The presence of L. infantum amastigotes and DNA in testicular and uterine tissue samples suggested that these organs can harbor the parasite without associated macroscopic or microscopic lesions, and this can be especially important in the vertical and venereal transmission of leishmaniasis in dogs.(AU)

Leishmania infantum é agente etiológico da leishmaniose canina. Por meio de análises parasitológicas e moleculares, a presença do parasita foi investigada em órgãos reprodutivos de cães machos e fêmeas. Amostras de tecidos dos órgãos reprodutivos de 8 cães machos e 16 fêmeas diagnosticados com leishmaniose foram avaliadas por histoquímica, imunohistoquímica e PCR. Apesar de não terem sido observadas lesões macroscópicas ou microscópicas nos órgãos reprodutivos desses cães, formas amastigotas de L. infantum foram observadas em amostras teciduais do testículo e útero. A PCR e o sequenciamento do DNA extraído desses tecidos revelaram sequências 100% idênticas a L. infantum depositadas no GenBank. Nossos resultados sugerem que os testículos e o útero podem abrigar o parasita, sem associação com lesões macroscópicas ou microscópicas, o que pode ter uma grande importância na transmissão venérea e vertical da leishmaniose entre cães.(AU)

Assuntos

RESUMO

Leishmania infantum causes canine leishmaniasis. Using parasitological and molecular analyses, we identified L. infantum in the reproductive organs of male and female dogs. Using histochemistry, immunohistochemistry, and PCR, we examined tissue samples from the reproductive organs of 8 male dogs and 16 female dogs diagnosed with leishmaniasis. Despite the absence of macroscopic or microscopic lesions in these organs, we observed L. infantum amastigotes in tissue samples from the testis and the uterus. PCR and sequencing of these tissues revealed sequences that matched 100% with L. infantum DNA available at GenBank. The presence of L. infantum amastigotes and DNA in testicular and uterine tissue samples suggested that these organs can harbor the parasite without associated macroscopic or microscopic lesions, and this can be especially important in the vertical and venereal transmission of leishmaniasis in dogs.

Leishmania infantum é agente etiológico da leishmaniose canina. Por meio de análises parasitológicas e moleculares, a presença do parasita foi investigada em órgãos reprodutivos de cães machos e fêmeas. Amostras de tecidos dos órgãos reprodutivos de 8 cães machos e 16 fêmeas diagnosticados com leishmaniose foram avaliadas por histoquímica, imunohistoquímica e PCR. Apesar de não terem sido observadas lesões macroscópicas ou microscópicas nos órgãos reprodutivos desses cães, formas amastigotas de L. infantum foram observadas em amostras teciduais do testículo e útero. A PCR e o sequenciamento do DNA extraído desses tecidos revelaram sequências 100% idênticas a L. infantum depositadas no GenBank. Nossos resultados sugerem que os testículos e o útero podem abrigar o parasita, sem associação com lesões macroscópicas ou microscópicas, o que pode ter uma grande importância na transmissão venérea e vertical da leishmaniose entre cães.

Assuntos

RESUMO

Genetic resistance is the main strategy to control one of the most destructive diseases of common bean (Phaseolus vulgaris L), i.e., the Fusarium wilt caused by Fusarium oxysporum f. sp. phaseoli (Fop). However, little is known on host defense reactions in Fop-bean interaction. Thus, this work examined the defense mechanisms in root and hypocotyl tissues of common bean against Fop. Resistant and susceptible bean plants were inoculated by dipping their roots in a conidial suspension. Cross sections of roots and hypocotyls were observed in light microscopy at 1, 3, 6, and 9 days after inoculation (dai) to monitor Fop colonization, and at 3 and 9 dai to detect callose, carbohydrates, lipids, phenolics, and protein, and under electronic microscopy at 9 dai to observe ultrastructural changes in xylem cells. The content of hydrogen peroxide (H2O2), lipid peroxidation, and activity of the antioxidant enzymes ascorbate peroxidase (EC 1.11.1.11) and catalase (EC 1.11.1.6) were monitored spectrophotometrically in roots and hypocotyls at 0, 1, 3, 6, and 9 dai. Fop colonized inter- and intracellularly the epidermis and cortex reaching the xylem vessels faster in susceptible genotype. Fop inoculation induced phenolics and carbohydrates accumulation, callose deposition, and formation of occlusion material inside xylem vessels mainly in resistant genotype. Lipid peroxidation occurred mainly in susceptible plants. In contrast, the antioxidant enzymes seem to have contributed to reducing damage caused by H2O2 accumulation in resistant plants. This study gives evidences that inter- and intracellular physicochemical mechanisms can act together to delay Fop colonization in resistant plants.

Assuntos