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1.
Artigo em Inglês | MEDLINE | ID: mdl-38652860

RESUMO

Phototherapies are promising for noninvasive treatment of aggressive tumors, especially when combining heat induction and oxidative processes. Herein, we show enhanced phototoxicity of gold shell-isolated nanorods conjugated with toluidine blue-O (AuSHINRs@TBO) against human colorectal tumor cells (Caco-2) with synergic effects of photothermal (PTT) and photodynamic therapies (PDT). Mitochondrial metabolic activity tests (MTT) performed on Caco-2 cell cultures indicated a photothermal effect from AuSHINRs owing to enhanced light absorption from the localized surface plasmon resonance (LSPR). The phototoxicity against Caco-2 cells was further increased with AuSHINRs@TBO where oxidative processes, such as hydroperoxidation, were also present, leading to a cell viability reduction from 85.5 to 39.0%. The molecular-level mechanisms responsible for these effects were investigated on bioinspired tumor membranes using Langmuir monolayers of Caco-2 lipid extract. Polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS) revealed that the AuSHINRs@TBO incorporation is due to attractive electrostatic interactions with negatively charged groups of the Caco-2 lipid extract, resulting in the expansion of surface pressure isotherms. Upon irradiation, Caco-2 lipid extract monolayers containing AuSHINRs@TBO (1:1 v/v) exhibited ca. 1.0% increase in surface area. This is attributed to the generation of reactive oxygen species (ROS) and their interaction with Caco-2 lipid extract monolayers, leading to hydroperoxide formation. The oxidative effects are facilitated by AuSHINRs@TBO penetration into the polar groups of the extract, allowing oxidative reactions with carbon chain unsaturations. These mechanisms are consistent with findings from confocal fluorescence microscopy, where the Caco-2 plasma membrane was the primary site of the cell death induction process.

2.
Photochem Photobiol ; 100(3): 772-781, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38100182

RESUMO

We report on the formation of toluidine blue O (TBO) sulfoxide by a self-sensitized photooxidation of TBO. Here, the photosulfoxidation process was studied by mass spectrometry (MS) and discussed in the context of photodemethylation processes which both contribute to TBO consumption over time. Analysis of solvent effects with D2O, H2O, and CH3CN along with product yields and MS fragmentation patterns provided mechanistic insight into TBO sulfoxide's formation. The formation of TBO sulfoxide is minor and detectable up to 12% after irradiation of 3 h. The photosulfoxidation process is dependent on oxygen wherein instead of a type II (singlet oxygen, 1O2) reaction, a type I reaction involving TBO to reach the TBO sulfoxide is consistent with the results. Density functional theory results point to the formation of the TBO sulfoxide by the oxidation of TBO via transiently formed peroxyl radical or thiadioxirane intermediates. We discover that the TBO photosulfoxidation arises competitively with TBO photodemethylation with the latter leading to formaldehyde formation.

3.
Reprod Domest Anim ; 58(7): 982-989, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37191500

RESUMO

The aim of this study was to evaluate the effectiveness of the original sperm chromatin dispersion (SCD) assay and the toluidine blue (TB) stain to assess DNA fragmentation and chromatin condensation, respectively, in cat sperm obtained by urethral catheterization (CT) and epididymis slicing (EP). CT and EP samples were collected from the same cat, and sperm motility, concentration, morphology, DNA integrity and chromatin condensation were evaluated. As controls, aliquots of the samples were incubated with 0.3 M NaOH and with 1% of dithiothreitol (DTT) to promote DNA fragmentation and chromatin decondensation, respectively. With SCD, four DNA dispersion halo patterns were observed: large, medium, small and no halo. TB staining patterns were as follows: light blue (condensed chromatin), light violet (moderate chromatin decondensation) and dark blue-violet (high chromatin decondensation). Sperm incubations with NaOH and with DTT were effective in inducing DNA fragmentation and chromatin decondensation, respectively. No significant differences were observed in the percentages of the SCD and TB patterns between samples (CT and EP) and no correlation was observed between sperm head abnormalities and the different SCD and TB patterns. The original SCD technique and the TB stain were adapted to evaluate DNA integrity and chromatin condensation in cat sperm obtained by CT and EP.


Assuntos
Cromatina , Cateterismo Urinário , Masculino , Animais , Cateterismo Urinário/veterinária , Epididimo , Hidróxido de Sódio , Sêmen , Motilidade dos Espermatozoides , Espermatozoides , DNA , Corantes , Cloreto de Tolônio , Fragmentação do DNA
4.
MethodsX ; 9: 101769, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35818446

RESUMO

Toxicity evaluations involve the analysis of multiple biomarkers. In this study, the liver, target organ analyzed by treatments with iron concentrations, indicated the accumulation of lipids as a response. Considering that the distribution of lipids in an organ is directly related to the induction of inflammatory processes by aquatic contaminants, this study proposes to carry out an integrative investigation of the behavior and the distribution of lipids in the liver tissue. Techniques of light and electron microscopy were performed in order to propose a new way of assessing and quantifying the distribution of lipid droplets, also presenting methodological alternatives that can be chosen by the reader according to the interests and resources available. Thus, it is assumed that the method begins with the fixation of the liver with Glutaraldehyde 2,5% in PBS 0,1 M and continues with post fixation with osmium tretoxide 1%, which marks lipids. For this proposition, two inclusion methodologies were performed to histological analyses in Historesin and ultrastructural analyses in EMBeed 812. For light microscopy (LM) analyses, cuts were obtained with 2,5 micrometers thickness, which were stained with (1) Mayers hematoxylin and (2) toluidine blue. The images obtained were processed in software Image J Fiji to evidence the lipid distribution in liver.•Cytological reactions with osmium tetroxide constitute low complexity methods that allow the optimization of the localization, identification and quantification of lipid droplets in the liver tissue when analyzed under the conventional light microscope.•Samples included in EMBeed 812 resin commonly used in Transmission Electron Microscopy can be analyzed by SEM-BEC, as complementary analyses for the detection of lipids.•Using SEM-BEC and conventional light microscopy, it is possible to quantify the area occupied by lipid droplets using Image J Fiji software, as these are contrasted due to the reaction with osmium tetroxide.

5.
Artigo em Inglês | MEDLINE | ID: mdl-35294686

RESUMO

In the present work, halloysite nanotubes modified with gold nanoparticles (AuNPs-HNT) are successfully prepared by wet chemical method for the catalytic degradation of phenothiazine dyes (azure B (AZB) and toluidine blue O (TBO)) and also cleaner reduction of 4-(4-nitrophenyl)morpholine (4NM) in the sodium borohydride (NaBH4) media. The catalyst is formulated by modifying the HNT support with a 0.964% metal loading using the HNT supports modified with 3-aminopropyl-trimethoxysilane (APTMS) coupling agent to facilitate the anchoring sites to trap the AuNPs and to prevent their agglomeration/aggregation. The AuNPs-HNT catalyst is investigated for structural and morphological characterization to get insights about the formation of the catalyst for the effective catalytic reduction of dyes and 4NM. The microscopic studies demonstrate that AuNPs (2.75 nm) are decorated on the outer surface of HNT. The as-prepared AuNPs-HNT catalyst demonstrates AZB and TBO dye degradation efficiency up to 96% in 10 and 11 min, respectively, and catalytic reduction of 4NM to 4-morpholinoaniline (MAN) is achieved up to 97% in 11 min, in the presence of NaBH4 without the formation of any by-products. The pseudo-first-order rate constant (K1) value of the AuNPs-HNT catalyst for AZB, TBO, and 4NM were calculated to be 0.0078, 0.0055, and 0.0066 s-1, respectively. Moreover, the synthesized catalyst shows an excellent reusability with stable catalytic reduction for 7 successive cycles for both the dyes and 4NM. A plausible mechanism for the catalytic dye degradation and reduction of 4NM by AuNPs-HNT catalyst is proposed as well. The obtained results clearly indicate the potential of AuNPs-HNT as an efficient catalyst for the removal of dye contaminants from the aquatic environments and cleaner reduction of 4NM to MAN, insinuating future pharmaceutical applications.

6.
Neotrop Entomol ; 51(1): 112-121, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34932199

RESUMO

The Neotropical brown stink bug, Euschistus heros (F.), feeds on stems, leaves, pods, and seeds of soybean, Glycine max (L.) Merrill. Knowledge of the damage that nymphs at different instars can cause to soybean pods and seeds, as well as efficient histological techniques for locating the salivary sheath are sparse. This study developed a new double-staining method to facilitate distinguishing the salivary sheath from plant tissues and to anatomically evaluate the damage caused by nymphs of different instars as they feed on soybean pods and seeds. Five insects from each of the analyzed instars (1st, 2nd, 3rd, 4th, and 5th) per pod at the R6 stage (full pod-filling) were kept in clip cages for 48 h of feeding. The salivary sheath was analyzed to localize the damage (pod, vascular bundle, and seed) and the depth reached by the damage (categorized tissue). Double staining with xylidine ponceau and toluidine blue provided the best differentiation between the salivary sheath and watery sheath (proteins stained red) and the plant tissues (stained blue). First instar nymphs do not feed. Second instar and older nymphs caused damage to seeds, which became more severe with later developmental stages. The damage consists of coalescence of protein bodies and degradation and breakdown of the cell wall, marked by darkened regions in the embryo tissue of seeds. The information generated will contribute to new studies on feeding habits and emphasizes the need to control E. heros in early development stages.


Assuntos
Glycine max , Heterópteros , Animais , Comportamento Alimentar , Técnicas Histológicas , Ninfa , Sementes
7.
Lasers Med Sci ; 37(1): 391-401, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33559803

RESUMO

Periodontitis is an infectious disease characterized by the destruction of supporting tissues. Antimicrobial photodynamic therapy (aPDT) has been proposed as an improved method for eliminating microorganisms. Its efficiency depends on the correct use of physical and chemical parameters. Thus, these parameters and their relations were evaluated in this study with the purpose of establishing lethal conditions for combating bacterial agents. Diode lasers and light-emitting diodes (LEDs) were characterized to evaluate the absorption profile and resonance of methylene blue (MB) and toluidine blue O (TBO). The relations between light energy density and photosensitizer absorption were determined. Two methodologies were used to evaluate the effects of aPDT against Aggregatibacter actinomycetemcomitans. LED light exhibited a broad emission spectrum with a peak light wavelength of 637 nm and 99% purity. The resonance intensity of MB was higher with diode laser irradiation, and TBO showed higher resonance intensity with LED irradiation. There was no difference in the absorption profile of photosensitizers using diode lasers or LEDs, and variations in power density did not result in an increasing or decrease in light absorption. A. actinomycetemcomitans was susceptible to photodynamic processes. Emission spectra and peak light wavelengths of light sources combined with the absorption profiles of photosensitizers were the main parameters involved in determining the efficiency of photodynamic effects. Power density did not alter the light absorption of photosensitizers. The association between adequate irradiation characteristics and photosensitizer absorption results in complete inactivation of A. actinomycetemcomitans. In addition, the bactericidal effect was not altered by an increase in energy densities.


Assuntos
Anti-Infecciosos , Fotoquimioterapia , Aggregatibacter actinomycetemcomitans , Fármacos Fotossensibilizantes/farmacologia , Cloreto de Tolônio
8.
Rev. méd. Urug ; 38(1): e38109, 2022.
Artigo em Espanhol | LILACS, UY-BNMED, BNUY | ID: biblio-1389676

RESUMO

Resumen: Introducción: la cirugía micrográfica de Mohs es una técnica quirúrgica especializada para el tratamiento del cáncer de piel no melanoma. La histopatología cumple un rol fundamental, y la elección de la tinción es un punto de controversia. Objetivos: comparar el rendimiento de las tinciones de hematoxilina y eosina (HyE) versus azul de toluidina (AT) durante la cirugía. Método: estudio observacional, descriptivo y transversal a partir de noviembre de 2017 hasta mayo de 2018. Se incluyeron las láminas empleadas durante la cirugía en el período mencionado. Estas fueron analizadas por el cirujano de Mohs, tres residentes y una dermopatóloga. Se valoró el rendimiento de ambas tinciones, teniendo en cuenta las características celulares y los elementos del estroma. Resultados: se estudiaron 23 tumores (16 carcinomas basocelulares y 7 carcinomas espinocelulares). Al observarse al microscopio óptico tanto con la tinción de AT como con HyE no se encontraron diferencias significativas entre ambos grupos en lo global, sólo en algunas características, especialmente con la HyE. Conclusiones: es el primer trabajo en Uruguay que compara la eficacia de las dos tinciones durante la cirugía micrográfica de Mohs. Como conclusión tanto la tinción de HyE como el AT son muy buenas técnicas para el diagnóstico de carcinomas cutáneos.


Abstract: Introduction: Mohs micrographic surgery is a specialized surgical technique used to treat nonmelanoma carcinoma. Histopathology plays a vital role in the diagnosis of this condition, and the choice staining method is controversial. Objective: to compare results in the use of hematoxylin and eosin (H&E) versus Toluidine blue (TB) staining during surgery. Method: observational, descriptive and transversal study conducted from November, 2017 until May, 2018 of the slides used during surgeries in the selected period. Slides were analysed by the Mohs surgeon, 3 residents and a dermopathologist to evaluate the results of both staining methods, in consideration of cell features and stromal elements. Results: 23 tumors were analysed (16 Basal Cell carcinomas and 7 Squamous Cell Carcinoma). Microscopic observation of slides prepared with Toluidine blue and hematoxylin and eosin stains did not show significant global differences between both groups, except in terms of a few characteristics, in particular with hematoxylin and eosin stains. Conclusions: this was the first study in Uruguay to evaluate the effectiveness of both staining methods during Mohs micrographic surgery, and it concluded that both Toluidine blue and hematoxylin and eosin stains are very good techniques in evaluating skin-cancer.


Resumo: Introdução: a cirurgia micrográfica de Mohs é uma técnica cirúrgica especializada para o tratamento do câncer de pele não melanoma. A histopatologia desempenha um papel fundamental, onde a escolha da coloração é um ponto de controvérsia. Objetivos: comparar o desempenho das colorações de hematoxilina e eosina versus azul de toluidina durante a cirurgia. Método: estudo observacional, descritivo e transversal de novembro de 2017 a maio de 2018. Foram incluídas as lâminas utilizadas durante as cirurgias no referido período. Estas foram analisadas pelo cirurgião especializado na técnica de Mohs, 3 residentes e um dermatopatologista onde foi avaliado o desempenho de ambas as colorações, levando em consideração as características celulares e os elementos do estroma. Resultados: foram estudados 23 tumores (16 carcinomas basocelulares e 7 carcinomas espinocelulares). Quando observados ao microscópio de luz para coloração AT e H&E, não foram encontradas diferenças significativas entre os dois grupos em geral, apenas em algumas características, especialmente com o H&E. Conclusões: é o primeiro estudo no Uruguai que compara a eficácia dos 2 corantes durante a cirurgia micrográfica de Mohs. Em conclusão, tanto a coloração com hematoxilina e eosina quanto com azul de toluidina são técnicas muito boas para o diagnóstico de carcinomas de pele.


Assuntos
Cirurgia de Mohs
9.
Autops Case Rep ; 11: e2021247, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307214

RESUMO

Actinic prurigo (AP) is a type of photodermatosis that primarily affects the Latin American mestizo population. Histologically, AP cheilitis exhibits acanthosis with spongiosis and vacuolation of the basal cell layer overlying a dense lymphocytic inflammatory infiltrate that forms well-defined lymphoid follicles. Toluidine blue is a thiazide, acidophilic, and metachromatic dye used in vivo to selectively stain the acidic components of tissues such as sulfates, carboxylates, and phosphate radicals that are incorporated into DNA and RNA. It is necessary to develop a method that allows detecting, on clinical grounds the area of the lesion in which it is more feasible to find such structures. Thus to increase the sensitivity of the biopsy, in AP cheilitis to accurately identify where the lymphoid follicles reside, based on the higher concentration of DNA in such structures and thus confirm the diagnosis. In this study, staining was positive in 85% of patients with AP cheilitis, in 14 of whom 82% lymphoid follicles were observed by histopathology. One of the pathologist's problems in establishing the diagnosis of AP is that the main histopathological characteristics are not always identified in the submitted samples because it is not easy to clinically identify the most representative site of the lesion selected for performing a biopsy. Based on our results, we propose using toluidine blue as an auxiliary method to choose a tissue sample to facilitate the diagnosis and allow clinicians to make clinical correlations between the histopathological and therapeutic findings.

10.
Theriogenology ; 161: 200-209, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33340753

RESUMO

The aim of this study was to evaluate the sperm head morphometry and chromatin condensation at different regions of the reproductive tract in bulls. Sperm smears of seminiferous tubules (ST), epididymis head (EH), body (EB), and tail (ET), and ductus deferens (DD) were stained with toluidine blue. Afterwards, the sperm head morphometry and chromatin alteration types were evaluated by a computational image analysis. Overall, spermatozoa of ST had lower (P < 0.05) area (A), perimeter (P), width (W), length (L), ellipticity (E), and Fourier harmonics (F0, F1, and F2). The chromatin decondensation (CD) and heterogeneity (CH) were higher (P < 0.05) in the ST region and decreased (P < 0.0001) during the migration along the reproductive tract (ST - DD direction). Considering the factors extracted (Factors 1 and 2) by the principal component analysis, the parameters A, P, W, L, and F0 were responsible for ∼36% of the Factor 1, while the E, F0, F1, and anterior-posterior symmetry (APS) contributed ∼27% to Factor 2. Both, CD and CH were associated with Factor 1 in the EH and ET regions and Factor 2 in the ST. Also, a well-defined difference between sperm heads collected from the ST and DD regions was observed by canonical analysis. The distribution of each chromatin alteration type was recorded. The proportion of normal sperm was lower (P < 0.05) in ST compared to other regions. Moreover, the chromatin influenced the morphometry and sperm heads with whole chromatin alteration type showed a smaller (P < 0.05) A, P, W, L, and E. In summary, the epididymal maturation is important for chromatin compaction and final morphometry of the sperm head. Also, the identification and quantification of the sperm chromatin condensation in different regions of reproductive tract can be used as potential biomarkers to predict the fertility in bulls.


Assuntos
Cromatina , Epididimo , Animais , Bovinos , Masculino , Túbulos Seminíferos , Cabeça do Espermatozoide , Espermatozoides , Ducto Deferente
11.
Autops. Case Rep ; 11: e2021247, 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1153188

RESUMO

Actinic prurigo (AP) is a type of photodermatosis that primarily affects the Latin American mestizo population. Histologically, AP cheilitis exhibits acanthosis with spongiosis and vacuolation of the basal cell layer overlying a dense lymphocytic inflammatory infiltrate that forms well-defined lymphoid follicles. Toluidine blue is a thiazide, acidophilic, and metachromatic dye used in vivo to selectively stain the acidic components of tissues such as sulfates, carboxylates, and phosphate radicals that are incorporated into DNA and RNA. It is necessary to develop a method that allows detecting, on clinical grounds the area of the lesion in which it is more feasible to find such structures. Thus to increase the sensitivity of the biopsy, in AP cheilitis to accurately identify where the lymphoid follicles reside, based on the higher concentration of DNA in such structures and thus confirm the diagnosis. In this study, staining was positive in 85% of patients with AP cheilitis, in 14 of whom 82% lymphoid follicles were observed by histopathology. One of the pathologist's problems in establishing the diagnosis of AP is that the main histopathological characteristics are not always identified in the submitted samples because it is not easy to clinically identify the most representative site of the lesion selected for performing a biopsy. Based on our results, we propose using toluidine blue as an auxiliary method to choose a tissue sample to facilitate the diagnosis and allow clinicians to make clinical correlations between the histopathological and therapeutic findings.


Assuntos
Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Prurigo/diagnóstico , Cloreto de Tolônio , Queilite/diagnóstico , Coloração e Rotulagem/métodos , Biópsia
12.
Vet World ; 13(8): 1627-1634, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33061237

RESUMO

BACKGROUND AND AIM: Mast cell tumors (MCTs) are malignant neoplasms that are common in dogs. Their biological behavior is variable and unpredictable. The aim of the present study was to analyze the histological classification and expression of markers of canine MCTs. MATERIALS AND METHODS: Thirty samples of canine MCTs were graded according to the histological classification methods of Patnaik and those of Kiupel. The expression of phosphoprotein 53 (p53) and c-kit proteins was quantified by immunohistochemistry using image processing software, ImageJ - a public domain computer program, developed at the National Institutes of Health. RESULTS: It was possible to determine the grade of 100% of the samples. According to Patnaik's classification, 20.00% of the samples were Grade 1, 43.30% were Grade 2, and 36.70% were Grade 3. According to Kiupel's classification, 56.67% of the samples were of high intensity and 43.33% were of low intensity. Grade 1 tumors had the highest expression of p53 and c-kit, and Grade 2 had the lowest expression. The results showed that it is necessary to perform both histological grading methods. The classification into high and low intensity may provide more consistent results than the three-level grading system. However, a smaller number of categories, although it facilitates the classification, may not be sufficient for the prognosis. CONCLUSION: Quantitative evaluation of p-53 and c-kit expression is a useful tool to increase the accuracy of the analysis and to aid in choosing the treatment method for canine MCTs. Histological grading should be combined with other diagnostic methods.

13.
Lasers Med Sci ; 35(1): 79-85, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31081523

RESUMO

Chagas disease is endemic in Latin America and increasingly found in non-endemic countries. Its treatment is limited due to the variable efficacy and several side effects of benznidazole. Photodynamic antimicrobial chemotherapy (PACT) may be an attractive approach for treating Chagas disease. Here, the trypanocidal activity of PACT was investigated in vitro using phenothiazine derivatives. The cytotoxicity of both, methylene blue (MB) and toluidine blue (TBO), was determined on macrophages cultures using AlamarBlue method. The trypanocidal activity of the two photosensitizers was initially evaluated by determining their IC50 values against trypomastigote forms. After this, the trypanocidal effect was evaluated in cultures of infected macrophages using an automatized image analysis protocol. All experiments were performed in the dark and in the clear phase (after a photodynamic exposure). The compounds showed no cytotoxicity in both phases at the tested concentrations. The IC50 values for the sole use of MB and TBO were 2.6 and 1.2 µM, respectively. The photoactivation of the compounds using a fixed energy density (J/cm2) caused a reduction of the IC50 values to 1.0 and 0.9 µM, respectively. It was found that, on infected macrophage, the use of TBO significantly reduced the number of infected cells and parasitic load, and this effect was increased in the presence of light. The results of the present study are indicative that PACT may be considered as both selective and effective therapeutic intervention for treating Chagas disease.


Assuntos
Antiparasitários/farmacologia , Fenotiazinas/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Anti-Infecciosos/farmacologia , Antiparasitários/uso terapêutico , Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Doença de Chagas/tratamento farmacológico , Humanos , Luz , Azul de Metileno/química , Azul de Metileno/farmacologia , Azul de Metileno/uso terapêutico , Camundongos Endogâmicos BALB C , Carga Parasitária , Fenotiazinas/uso terapêutico , Fármacos Fotossensibilizantes/uso terapêutico , Cloreto de Tolônio/química , Cloreto de Tolônio/farmacologia , Cloreto de Tolônio/uso terapêutico , Trypanosoma cruzi/efeitos da radiação
14.
Reprod Domest Anim ; 54(8): 1078-1084, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31187909

RESUMO

The toluidine blue (TB) stain has been used in different species to evaluate the degree of chromatin condensation. The objectives of this study were as follows: simplify the TB stain to evaluate sperm in canine raw semen, verify the staining patterns for this species using this simplified technique and establish a protocol for using dithiothreitol (DTT) as a positive control for TB staining in dogs. Twenty-one ejaculates were collected from 7 adult male dogs; semen was extended, fixed with ethanol 96° and stained with TB using 2 staining times: 15 and 30 min. In addition, 3 incubation times with 1% DTT were assayed (2, 5 and 30 min). Three staining patterns were established: light blue colouring (TB negative, normal chromatin condensation), light violet (TB intermediate, some degree of chromatin decondensation) and dark blue-violet (TB positive, high degree of chromatin decondensation). No significant differences (p > 0.05) were observed between the staining times (15 and 30 min) for any of the TB patterns. All DTT incubation times (2, 5 and 30 min) showed 100% sperm positive to TB. To conclude, it was possible to simplify the TB stain and determine the different patterns in canine spermatozoa. Also, DTT can be used both as a positive control for the stain and to evaluate individual susceptibility to decondensation in vitro.


Assuntos
Corantes/química , DNA/química , Análise do Sêmen/veterinária , Cloreto de Tolônio/química , Animais , Cromatina/ultraestrutura , Cães , Masculino , Sêmen/citologia , Análise do Sêmen/métodos , Espermatozoides/citologia , Coloração e Rotulagem/métodos , Coloração e Rotulagem/veterinária
15.
Photodiagnosis Photodyn Ther ; 25: 421-424, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30611865

RESUMO

BACKGROUND: The thermo-dimorphic fungus Paracoccidioides brasiliensis is the pathogen of Paracoccidioidomycosis, an important public health problem in Latin American with prevalence in Brazil. Photodynamic Antimicrobial Chemotherapy (PACT) is a process that combines a photosensitizer and light, producing reactive oxygen species (ROS) that can promote damages to treated cells. METHODS: In this work was study the effect of PACT, using Toluidine blue (TBO) on both yeast and mycelial cells of P. brasiliensis. RESULTS: It was observed that PACT decreased P. brasiliensis yeast growth, in a dependent manner of both TBO concentrations and fluence. In the presence of TBO 0.005 mg/mL, PACT reduced P. brasiliensis yeast growth in 63, 62 and 86%, using fluences of 20, 30 and 40 J/cm2, respectively. After PACT, ROS production increased 2.80, 4.64 and 7.90 times, in the presence of TBO 0.001, 0.002 and 0.005 mg/mL, respectively. It was observed that after PACT, the cells are predominantly in mycelia form, indicating that mycelial cells irradiated in the presence of TBO, maintained their filamentous form and absence and/or decreased presence of transition structures. CONCLUSIONS: These results demonstrated the potential of PACT, using TBO to inhibit both yeast and mycelium development of P. brasiliensis.


Assuntos
Paracoccidioides/efeitos dos fármacos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Cloreto de Tolônio/farmacologia , Biofilmes/efeitos dos fármacos , Brasil , Relação Dose-Resposta a Droga
16.
Acta Histochem ; 121(2): 101-112, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30463688

RESUMO

Toluidine blue (TB) staining either alone or in association with other methodologies has the potential to answer a variety of biological questions regarding the human, animal and plant tissues or cells. In this brief review, we not only report the primary use of TB to detect the anionic substrates and availability of their binding sites, but also unveil the resulting applications of TB staining in biological research. Among these applications, the uses of TB staining to identify the changes in chromatin DNA-protein complexes, nucleolus location, and extracellular matrix proteoglycan complexes associated with different physiological and pathological events are described. The usefulness of TB staining to monitor the effects elicited by environmental insults on chromatin and intercalation of drugs into the DNA is also included.


Assuntos
Cromatina/metabolismo , DNA , Coloração e Rotulagem , Cloreto de Tolônio , Animais , Sítios de Ligação/fisiologia , Humanos , Proteoglicanas/metabolismo , Coloração e Rotulagem/métodos
17.
Int. j. morphol ; 36(3): 962-968, Sept. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-954215

RESUMO

This study was aimed at comparing the commonly used metachromatic stains viz., Papanicolaou stain, WrightGiemsa, Toluidine blue and Methylene blue in the assessment of cell types of the oestrous cycle in rats. Eight female Sprague-Dawley rats aged 8-9 weeks were used for this assessment. Cotton Swabs were gently inserted in the animals vagina to obtain cells from which they were then transferred to glass slides for staining and evaluation under microscopy. The different cell types were compared for their morphological features and clarity of cellular detail under all four stains. The application, advantages and limitations of all stains were then discussed. It was concluded that the selection of the most effective stain in the assessment of vaginal cytology depends on their application to clinical or research which was based on the cellular detail of interest, time, cost and availability of each staining procedure.


El presente estudio tuvo como objetivo comparar las tinciones metacromáticas comúnmente utilizadas, Wright's-Giemsa, azul de toluidina, azul de metileno y tinción de Papanicolaou, en la evaluación de los tipos de células del ciclo estral en ratas. El estudio se realizó en ocho ratas hembras SpragueDawley, con edades entre 8 y 9 semanas, y se usaron hisopos vaginales de algodón para preparar portaobjetos. Los diferentes tipos de células se compararon por sus características morfológicas y claridad en las cuatro tinciones. La aplicación, ventajas y limitaciones de todas las tinciones fueron discutidas. Se concluye que la selección de la tinción más efectiva en la evaluación de la citología vaginal depende de su uso, es decir, clínico o de investigación, el detalle celular de interés, tiempo, costo y disponibilidad.


Assuntos
Animais , Feminino , Ratos , Coloração e Rotulagem/métodos , Vagina/citologia , Técnicas Citológicas/métodos , Ciclo Estral , Corantes Azur , Cloreto de Tolônio , Corantes , Teste de Papanicolaou , Azul de Metileno
18.
Reprod Biol ; 18(2): 177-181, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29705068

RESUMO

Alterations in sperm chromatin have been related with subfertility in several mammals. In this study, chromatin alteration types (Base, Basal half, Central axis, Dispersed, and Whole) were assessed by toluidine blue (TB) staining, 6-diamidino-2-fenilindole (DAPI) and anti-protamine 1 antibody (anti-PR1) labeling in sperm samples of fertile and subfertile bulls. Semen samples were obtained from bulls kept in Artificial Insemination Center (fertile bulls) or from bulls subjected to scrotal insulation (subfertile bulls). The percentage of chromatin alterations identified by TB was similar (P > 0.05) in semen samples of fertile and subfertile bulls. In contrast, a greater (P < 0.01) chromatin decondensation and heterogeneity were recorded in semen samples of subfertile bulls. In DAPI and anti-PR1 methods, the subfertile bulls samples had a higher (P < 0.05) percentage of alteration in the base as well as overall chromatin alterations (P < 0.05). Moreover, the chromatin alterations recorded with TB, DAPI, and anti-PR1 were compared in semen samples of fertile and subfertile bulls. In fertile bulls, the overall chromatin alterations were similar (P > 0.05) among the methods In contrast, semen samples of subfertile bulls had a higher (P < 0.05) percentage of overall chromatin alterations when labeled with DAPI. In conclusion, our findings shown that all dye tested had specific sperm stainability and can be feasible to monitor subfertility condition in bulls. Also, different chromatin alteration types in sperm samples of fertile and suberftile bulls were recorded.


Assuntos
Cromatina/metabolismo , Fertilidade/fisiologia , Infertilidade Masculina/veterinária , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo , Animais , Bovinos , Infertilidade Masculina/metabolismo , Inseminação Artificial/veterinária , Masculino
19.
Pesqui. vet. bras ; 38(4): 649-658, abr. 2018. tab, graf
Artigo em Português | VETINDEX | ID: vti-20563

RESUMO

A babesiose é uma doença hemolítica transmitida por carrapatos e causada por protozoários intraeritrocitários do gênero Babesia. Esta é uma doença de incidência elevada na Região Sul do Brasil e responsável por perdas econômicas consideráveis. O diagnóstico clínico-patológico pode ser feito através da demonstração do parasito pelo exame de esfregaços sanguíneos ou de tecidos frescos. Entretanto, com frequência, somente órgãos fixados em formol são remetidos para laboratórios de patologia, o que impossibilita a realização do esfregaço. O principal objetivo deste estudo foi encontrar técnicas histoquímicas alternativas e capazes de aprimorar a evidenciação de Babesia bovis intraeritrocitária em tecidos fixados em formol. Para este estudo, foram analisadas retrospectivamente amostras de tecidos de 50 casos de necropsias de bovinos, as quais haviam sido fixadas em formol e processadas rotineiramente para histopatologia. Os casos foram divididos em um grupo controle, constituído por 12 casos de babesiose cerebral com substância cinzenta encefálica róseo-cereja característica (grupo A), e 38 casos sugestivos de tristeza parasitária bovina (grupo B), conforme os protocolos de necropsias. Foram testadas as técnicas histoquímicas de Azul Alciano, Azul de Metileno, Azul de Toluidina, Giemsa, Gram (método de McCallum-Goodpasture), Grocott, Ácido Periódico de Schiff e Ziehl-Neelsen. Dentre estas, observou-se que as técnicas de Azul de Metileno e Azul de Toluidina permitiram observar características morfológicas e tintoriais de maneira mais nítida, auxiliando na identificação de B. bovis. Adicionalmente, foram estabelecidos vários parâmetros clínico-epidemiológicos e anatomopatológicos da babesiose por B. bovis.(AU)


Babesiosis is a hemolytic tick-borne disease caused by intraerythrocytic protozoal parasites of the genus Babesia. This is a disease of high incidence in the southern Brazil and responsible for considerable economic losses. Clinical-pathological diagnosis can be made by demonstrating the parasite by examining blood smears or fresh tissues. However, frequently, only formalin-fixed organs are sent to pathology laboratories, which makes it impossible to perform the smears. The main objective of this study was to find alternative histochemical techniques capable to improve the identification of intraerythrocytic Babesia bovis in histological sections. For this study, tissue samples from 50 bovine necropsy cases were retrospectively analyzed, which had been fixed in formalin and routinely processed for histopathology. The cases were divided into a control group, consisting of 12 cases of cerebral babesiosis with characteristic pink-cherry gray matter (group A), and 38 cases suggestive of cattle tick fever (group B), according to necropsy protocols. Histochemical techniques of Alcian Blue, Methylene Blue, Toluidine Blue, Giemsa, Gram (McCallum-Goodpasture method), Grocott, Periodic Acid of Schiff and Ziehl-Neelsen were tested. Among these, it was observed that the techniques of Methylene Blue and Toluidine Blue allowed to observe morphological and dye characteristics in a clearer way, aiding in the identification of B. bovis. In addition, several clinical-epidemiological and anatomopathological parameters of babesiosis caused by B. bovis were established.(AU)


Assuntos
Animais , Bovinos , Babesiose/classificação , Babesiose/diagnóstico , Imuno-Histoquímica/veterinária , Babesia bovis
20.
Pesqui. vet. bras ; Pesqui. vet. bras;38(4): 649-658, abr. 2018. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-955369

RESUMO

A babesiose é uma doença hemolítica transmitida por carrapatos e causada por protozoários intraeritrocitários do gênero Babesia. Esta é uma doença de incidência elevada na Região Sul do Brasil e responsável por perdas econômicas consideráveis. O diagnóstico clínico-patológico pode ser feito através da demonstração do parasito pelo exame de esfregaços sanguíneos ou de tecidos frescos. Entretanto, com frequência, somente órgãos fixados em formol são remetidos para laboratórios de patologia, o que impossibilita a realização do esfregaço. O principal objetivo deste estudo foi encontrar técnicas histoquímicas alternativas e capazes de aprimorar a evidenciação de Babesia bovis intraeritrocitária em tecidos fixados em formol. Para este estudo, foram analisadas retrospectivamente amostras de tecidos de 50 casos de necropsias de bovinos, as quais haviam sido fixadas em formol e processadas rotineiramente para histopatologia. Os casos foram divididos em um grupo controle, constituído por 12 casos de babesiose cerebral com substância cinzenta encefálica róseo-cereja característica (grupo A), e 38 casos sugestivos de tristeza parasitária bovina (grupo B), conforme os protocolos de necropsias. Foram testadas as técnicas histoquímicas de Azul Alciano, Azul de Metileno, Azul de Toluidina, Giemsa, Gram (método de McCallum-Goodpasture), Grocott, Ácido Periódico de Schiff e Ziehl-Neelsen. Dentre estas, observou-se que as técnicas de Azul de Metileno e Azul de Toluidina permitiram observar características morfológicas e tintoriais de maneira mais nítida, auxiliando na identificação de B. bovis. Adicionalmente, foram estabelecidos vários parâmetros clínico-epidemiológicos e anatomopatológicos da babesiose por B. bovis.(AU)


Babesiosis is a hemolytic tick-borne disease caused by intraerythrocytic protozoal parasites of the genus Babesia. This is a disease of high incidence in the southern Brazil and responsible for considerable economic losses. Clinical-pathological diagnosis can be made by demonstrating the parasite by examining blood smears or fresh tissues. However, frequently, only formalin-fixed organs are sent to pathology laboratories, which makes it impossible to perform the smears. The main objective of this study was to find alternative histochemical techniques capable to improve the identification of intraerythrocytic Babesia bovis in histological sections. For this study, tissue samples from 50 bovine necropsy cases were retrospectively analyzed, which had been fixed in formalin and routinely processed for histopathology. The cases were divided into a control group, consisting of 12 cases of cerebral babesiosis with characteristic pink-cherry gray matter (group A), and 38 cases suggestive of cattle tick fever (group B), according to necropsy protocols. Histochemical techniques of Alcian Blue, Methylene Blue, Toluidine Blue, Giemsa, Gram (McCallum-Goodpasture method), Grocott, Periodic Acid of Schiff and Ziehl-Neelsen were tested. Among these, it was observed that the techniques of Methylene Blue and Toluidine Blue allowed to observe morphological and dye characteristics in a clearer way, aiding in the identification of B. bovis. In addition, several clinical-epidemiological and anatomopathological parameters of babesiosis caused by B. bovis were established.(AU)


Assuntos
Animais , Bovinos , Babesiose/classificação , Babesiose/diagnóstico , Imuno-Histoquímica/veterinária , Babesia bovis
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