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2.
Micron ; 186: 103692, 2024 11.
Artigo em Inglês | MEDLINE | ID: mdl-39111185

RESUMO

Rhus typhina is a valuable plant used in the pharmaceutical, cosmetic, and food industries due to the presence of biologically active substances accumulated in its organs, especially in secretory structures, i.e. trichomes and secretory ducts. Light microscopy, scanning electron microscopy, and transmission electron microscopy were used to examine the structure of glandular and non-glandular trichomes, as well as secretory ducts present in inflorescence peduncles of R. typhina. The chemical composition of the secretion produced by trichomes and ducts was assessed using histochemical techniques, including observations under brightfield and fluorescence microscopes. Two types of capitate glandular trichomes producing secretions with a similar composition and non-glandular trichomes exhibiting secretory activity were identified. The secretion of glandular trichomes was dominated by acidic and neutral lipids, essential oil, sesquiterpenes, and steroid-containing terpenes. The schizogenic secretory ducts located in the phloem produced a viscous milky substance with acidic polysaccharides, acidic lipids, phenolic compounds, and proteins. The secretion was released into the duct lumen through notches in the walls of the secretory epithelial cell facing the duct lumen. The location, type, and traits of the non-glandular trichomes and secretory structures, as well as the composition of the secreted products are considered important taxonomic features in the family Anacardiaceae and the Rhus genus. Additionally, these characters are important diagnostic markers for the pharmacobotanical identification of the species in medicinal and cosmetic raw materials. The various compounds present in the secretory structures of R. typhina may contribute to plant protection against pathogens or herbivory and probably play a role as attractants for pollinators and seed dispersers.


Assuntos
Rhus , Tricomas , Tricomas/ultraestrutura , Tricomas/metabolismo , Rhus/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Óleos Voláteis/química , Histocitoquímica
3.
Int J Mol Sci ; 25(15)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39125610

RESUMO

All the nanotechnological devices designed for medical purposes have to deal with the common requirement of facing the complexity of a living organism. Therefore, the development of these nanoconstructs must involve the study of their structural and functional interactions and the effects on cells, tissues, and organs, to ensure both effectiveness and safety. To this aim, imaging techniques proved to be extremely valuable not only to visualize the nanoparticles in the biological environment but also to detect the morphological and molecular modifications they have induced. In particular, histochemistry is a long-established science able to provide molecular information on cell and tissue components in situ, bringing together the potential of biomolecular analysis and imaging. The present review article aims at offering an overview of the various histochemical techniques used to explore the impact of novel nanoproducts as therapeutic, reconstructive and diagnostic tools on biological systems. It is evident that histochemistry has been playing a leading role in nanomedical research, being largely applied to single cells, tissue slices and even living animals.


Assuntos
Imagem Molecular , Nanomedicina , Humanos , Animais , Imagem Molecular/métodos , Nanomedicina/métodos , Nanopartículas/química , Histocitoquímica/métodos
4.
J Infect Dev Ctries ; 18(6): 895-899, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38990991

RESUMO

INTRODUCTION: Diagnosis of cutaneous leishmaniasis (CL) is difficult, and the correct use of histopathological criteria can be useful in clinical practice. The present study evaluates the association between histopathological findings and the results of polymerase chain reaction (PCR) in clinically suspected cases of CL. METHODOLOGY: Skin samples were received in a laboratory from an endemic region of Brazil for over nine years. Associations were analyzed by means of the Chi square test with a 5% level of significance. RESULTS: Of the 222 examined samples, 190 (85.6%) tested positive by PCR. All 25 cases identified by microscopic examination also tested positive by PCR. Except for the more intense inflammatory infiltrate, all other evaluated histological variables (ulceration, epidermal hyperplasia, hyperkeratosis, presence of granuloma, neutrophils, histiocytes, lymphocytes, plasmocytes, and necrosis) were not significantly associated with PCR positivity. CONCLUSIONS: The intensity of the inflammatory infiltrate is a good indicator of the occurrence of CL. Histopathological aspects are useful to increase the predictive values of CL diagnoses, but PCR is still necessary to confirm or exclude the disease.


Assuntos
Doenças Endêmicas , Leishmaniose Cutânea , Reação em Cadeia da Polimerase , Pele , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/patologia , Leishmaniose Cutânea/epidemiologia , Humanos , Brasil/epidemiologia , Reação em Cadeia da Polimerase/métodos , Masculino , Pele/patologia , Pele/parasitologia , Feminino , Adulto , Pessoa de Meia-Idade , Adolescente , Criança , Adulto Jovem , Histocitoquímica , Pré-Escolar , Idoso
5.
Micron ; 185: 103691, 2024 10.
Artigo em Inglês | MEDLINE | ID: mdl-39032209

RESUMO

We describe the histological organisation and mucin content in the digestive tract of the stream catfish Pseudecheneis sulcatus. The aim is to find the modifications of the digestive tract in relation to food resources of its habitat. The oesophageal mucosa consists of stratified squamous epithelium with many mucous-secreting cells. The thick muscularis contains an inner longitudinal and outer circular, striated muscle cells. The stomach is J-shaped and shows 6-7 thick mucosal folds that are separated from the submucosa by an organised muscularis mucosae. The mucosa consists of superficial cells with mucin granules, and deeper simple tubular gastric glands in cardia and fundus, but absent in pyloric region. The glandular epithelium shows oxynticopeptic cells containing zymogen granules and abundant tubulo-vesicular bodies. We provide evidence that the latter arise by budding from smooth endoplasmic reticulum and reach the apical cytoplasm. The anterior intestine shows longer mucosal folds with goblet cells (GC). GC are more in the posterior intestine and highest in the rectum. Myenteric neurons with myelinated and non-myelinated axons innervate the intrinsic musculature from stomach to rectum. Many stem cells are evident in the basal intestinal epithelium. They show darker nuclei and undifferentiated organelles. Mucin histochemistry reveals the predominance of neutral mucin (PAS+ positive) from oesophagus to rectum, and neutral and acidic mucin (alcian blue+, pH 2.5) in the posterior intestine to the rectum, with few GC colocalizing both. Ultrastructural features suggest that the species is adapted to omnivory and this is reflected in the predominance of neutral mucin in the digestive tract.


Assuntos
Peixes-Gato , Trato Gastrointestinal , Mucinas , Animais , Peixes-Gato/anatomia & histologia , Trato Gastrointestinal/anatomia & histologia , Trato Gastrointestinal/citologia , Mucinas/metabolismo , Mucosa Gástrica/ultraestrutura , Mucosa Gástrica/citologia , Mucosa Gástrica/anatomia & histologia , Histocitoquímica
6.
J Infect Dev Ctries ; 18(7): 1141-1144, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39078781

RESUMO

INTRODUCTION: Breast tuberculosis (TB) is a rare extra-pulmonary presentation of tuberculosis. In the western world, this accounts for less than 0.1% of breast conditions (all breast conditions, not limited to TB or extra-pulmonary TB), but can be up to 3-4% in regions endemic for TB such as in Africa and Asia. CASE PRESENTATION: We report a case of a 54-year- old human immunodeficiency virus (HIV)-positive lady who presented with six months history of multiple masses on the left breast which were initially suspected to be cancer of the breast. However, histology report of the mass confirmed TB of the breast. CONCLUSIONS: Presentation of TB can be non-specific and atypical in patients with HIV infection, especially when it presents in extra-pulmonary forms.


Assuntos
Infecções por HIV , Tuberculose , Humanos , Feminino , Pessoa de Meia-Idade , Tuberculose/diagnóstico , Tuberculose/complicações , Tuberculose/patologia , Infecções por HIV/complicações , Doenças Mamárias/microbiologia , Doenças Mamárias/diagnóstico , Doenças Mamárias/patologia , Mama/patologia , Mama/diagnóstico por imagem , Histocitoquímica
9.
Indian J Pathol Microbiol ; 67(3): 730, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39078985
10.
IEEE J Biomed Health Inform ; 28(10): 6019-6030, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38913517

RESUMO

Matching whole slide histopathology images to provide comprehensive information on homologous tissues is beneficial for cancer diagnosis. However, the challenge arises with the Giga-pixel whole slide images (WSIs) when aiming for high-accuracy matching. Learning-based methods are difficult to generalize well with large-size WSIs, necessitating the integration of traditional matching methods to enhance accuracy as the size increases. In this paper, we propose a multi-size guiding matching method applicable high-accuracy requirements. Specifically, we design learning multiscale texture to train deep descriptors, called TDescNet, that trains 64 × 64 × 256 and 256 × 256 × 128 size convolution layer as C64 and C256 descriptors to overcome staining variation and low visibility challenges. Furthermore, we develop the 3D-ring descriptor using sparse keypoints to support the description of large-size WSIs. Finally, we employ C64, C256, and 3D-ring descriptors to progressively guide refined local matching, utilizing geometric consistency to identify correct matching results. Experiments show that when matching WSIs of size 4096 × 4096 pixels, our average matching error is 123.48 µm and the success rate is 93.02 % in 43 cases. Notably, our method achieves an average improvement of 65.52 µm in matching accuracy compared to recent state-of-the-art methods, with enhancements ranging from 36.27 µm to 131.66 µm. Therefore, we achieve high-fidelity whole-slice image matching, and overcome staining variation and low visibility challenges, enabling assistance in comprehensive cancer diagnosis through matched WSIs.


Assuntos
Aprendizado Profundo , Interpretação de Imagem Assistida por Computador , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Algoritmos , Coloração e Rotulagem/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Redes Neurais de Computação , Histocitoquímica/métodos , Processamento de Imagem Assistida por Computador/métodos
15.
Microsc Microanal ; 30(3): 539-551, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38758132

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease of unknown origin with limited treatment options and poor prognosis. The encouraging findings from preclinical investigations utilizing mesenchymal stem cells (MSCs) indicated that they could serve as a promising therapeutic alternative for managing chronic lung conditions, such as IPF. The objective of this study was to compare the efficiency of bone marrow-derived MSCs (BM-MSCs) versus prednisolone, the standard anti-inflammatory medication, in rats with bleomycin (BLM)-induced lung fibrosis. Four groups were created: a control group, a BLM group, a prednisolone-treated group, and a BM-MSCs-treated group. To induce lung fibrosis, 5 mg/kg of BLM was administered intratracheally. BLM significantly increased serum levels of pro-inflammatory cytokines and oxidative stress markers. The disturbed lung structure was also revealed by light and transmission electron microscopic studies. Upregulation in the immune expression of alpha-smooth muscle actin, transforming growth factor beta-1, and Bax was demonstrated. Interestingly, all findings significantly regressed on treatment with prednisolone and BM-MSCs. However, treatment with BM-MSCs showed better results than with prednisolone. In conclusion, BM-MSCs could be a promising approach for managing lung fibrosis.


Assuntos
Bleomicina , Modelos Animais de Doenças , Células-Tronco Mesenquimais , Prednisolona , Fibrose Pulmonar , Animais , Prednisolona/uso terapêutico , Prednisolona/farmacologia , Ratos , Fibrose Pulmonar/terapia , Fibrose Pulmonar/patologia , Pulmão/patologia , Imuno-Histoquímica , Masculino , Citocinas/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Transplante de Células-Tronco Mesenquimais/métodos , Histocitoquímica , Células da Medula Óssea , Microscopia Eletrônica de Transmissão
16.
Microsc Res Tech ; 87(9): 2143-2153, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38706034

RESUMO

In the Medicago genus, saponins are complex mixtures of triterpene pentacyclic glycosides extensively studied for their different and economically relevant biological and pharmaceutical properties. This research is aimed at determining for the first time the tissue and cellular localization of triterpene saponins in vegetative organs of Medicago truncatula, a model plant species for legumes, by histochemistry and transmission electron microscopy. The results showed that saponins are present mainly in the palisade mesophyll layer of leaves, whereas in stems they are mostly located in the primary phloem and the subepidermal cells of cortical parenchyma. In root tissue, saponins occur in the secondary phloem region. Transmission electron microscopy revealed prominent saponin accumulation within the leaf and stem chloroplasts, while in the roots the saponins are found in the vesicular structures. Our results demonstrate the feasibility of using histochemistry and transmission electron microscopy to localize M. truncatula saponins at tissue and cellular levels and provide important information for further studies on biosynthesis and regulation of valuable bioactive saponins on agronomic relevant Medicago spp., such as alfalfa (Medicago sativa L.). RESEARCH HIGHLIGHTS: The Medicago genus represents a valuable rich source of saponins, one of the most interesting groups of secondary plant metabolites, which possess relevant biological and pharmacological properties. Plant tissue and cellular localization of saponins is of great importance to better understand their biological functions, biosynthetic pathway, and regulatory mechanisms. We elucidate the localization of saponins in Medicago truncatula with histochemical and transmission electron microscopy studies.


Assuntos
Medicago truncatula , Microscopia Eletrônica de Transmissão , Folhas de Planta , Raízes de Plantas , Saponinas , Triterpenos , Medicago truncatula/ultraestrutura , Medicago truncatula/metabolismo , Medicago truncatula/química , Saponinas/metabolismo , Triterpenos/metabolismo , Triterpenos/química , Raízes de Plantas/química , Raízes de Plantas/ultraestrutura , Folhas de Planta/química , Folhas de Planta/ultraestrutura , Caules de Planta/química , Caules de Planta/ultraestrutura , Floema/ultraestrutura , Floema/química , Floema/metabolismo , Histocitoquímica , Cloroplastos/ultraestrutura , Cloroplastos/metabolismo , Cloroplastos/química
17.
Microsc Res Tech ; 87(9): 2241-2249, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38721845

RESUMO

At 22nd day of fetal development, the primordial anlage of mandibular gland was first noticed as a solid epithelial bud from oral epithelium. The terminal buds were arranged in the form of clusters with undifferentiated epithelial cells and terminated in a bulb like structure in 28-day-old fetus. The lumenization and branching of the main cord was noticed at 35th day. The primary septa, which divide the glandular mass into lobes was observed from 53rd day onwards which resulted in the formation of distinct lobulation at 58th day. At 61st day, the capsule formation was initiated by the aggregation of mesenchymal tissue. The terminal tubules differentiated to form the secretory end pieces and the tubular portion leads to the formation of intercalated and striated ducts at 98th day. Predominantly mucous types of acinar cells were seen from 108th day onwards. The number of lobules increased with steep increase in parenchyma from 128th day onwards. Micrometrical studies revealed that the mean diameter of acinar cells and all ducts was increased with the advancement of age and the significant differences were observed between groups. Localization of acidic and neutral mucopolysaccharides was observed in mucous cells and goblet cells. RESEARCH HIGHLIGHTS: The primordial anlage of mandibular salivary gland was seen at 22nd day. Lobulation of gland was appeared at 53rd day of development, however; it was completed at 58th day. At 98th day, the terminal tubules differentiated to form the secretory end pieces. The parenchyma of the gland showed predominantly mucous type of cells from 108th day onwards. Myoepithelial cells were first appeared as flattened basal cells initially around the developing acinar cells at 132nd day. Localization of acidic as well as neutral mucopolysaccharides was observed in mucous cells and goblet cells. Fine lipid droplets were observed in intralobular as well as interlobular connective tissue, however; phospholipids were observed in the cell membrane of secretory cells and ducts.


Assuntos
Mandíbula , Glândulas Salivares , Animais , Glândulas Salivares/embriologia , Glândulas Salivares/citologia , Mandíbula/embriologia , Mandíbula/anatomia & histologia , Ovinos/embriologia , Células Acinares/citologia , Células Caliciformes/citologia , Histocitoquímica , Células Epiteliais/citologia , Feminino
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