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1.
Bioessays ; 46(5): e2300122, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38514402

RESUMO

Fluorescence microscopy is a powerful tool used in scientific and medical research, but it is inextricably linked to phototoxicity. Neglecting phototoxicity can lead to erroneous or inconclusive results. Recently, several reports have addressed this issue, but it is still underestimated by many researchers, even though it can lead to cell death. Phototoxicity can be reduced by appropriate microscopic techniques and carefully designed experiments. This review focuses on recent strategies to reduce phototoxicity in microscopic imaging of living cells and tissues. We describe digital image processing and new hardware solutions. We point out new modifications of microscopy methods and hope that this review will interest microscopy hardware engineers. Our aim is to underscore the challenges and potential solutions integral to the design of microscopy systems. Simultaneously, we intend to engage biologists, offering insight into the latest technological advancements in imaging that can enhance their understanding and practice.


Assuntos
Microscopia de Fluorescência , Humanos , Microscopia de Fluorescência/métodos , Animais , Processamento de Imagem Assistida por Computador/métodos
2.
BMC Plant Biol ; 24(1): 694, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039438

RESUMO

BACKGROUND: This study was aimed to determine the taxonomic position and delimitation of fifteen Lamiaceae taxa using leaf epidermal morpho-anatomical features in Lahore. A main objective of the study was also the revision and upgradation of Lamiaceae taxa in the flora of Pakistan, as no details of studied species are found in the flora of Pakistan. METHODS: The examination of significant anatomical parameters, such as epidermal cell shape and size, stomatal types, guard and subsidiary cells shape and size, stomatal cavity size, trichome size and shape, oil droplets, crystals, and secretory cavity characteristics were studied using light microscopic (LM) and scanning electron microscopic (SEM) techniques. Among all the studied Lamiaceae species, these anatomical features varied significantly. Principal component analysis and correlation were done to distinguish the species' similarities. RESULTS: Most species had pentagonal and hexagonal epidermal cells with straight anticlinal wall thickness. On the adaxial surface, paracytic stomata were found in Ocimum basilicum L. and Rosmarinus officinalis L. Diacytic stomata was observed in Ajuga reptans L. and anisocytic stomata in Galeopsis tetrahit L. In the abaxial surface, trichomes were present in five species, i.e., Mentha suaveolens Ehrh. A. reptans, Thymus vulgaris L., M. haplocalyx, and Salvia splendens Ewat. In S. splendens, peltate and glandular trichomes were seen whereas, in other species, trichomes were long, unbranched glandular and had tapering ends. In adaxial side trichomes were present only in M. suaveolens, A. reptans, S. bazyntina, O. basciculum, S. splendens, S. officinalis, S. rosemarinus. In other species, trichomes were absent on the adaxial surface. In abaxial view, M. suaveolens had the largest length of trichomes, and O. basciculum had the smallest. S. splendens L. had the largest trichome width, while T. vulgaris had the smallest. CONCLUSION: Hence, according to these findings, morpho-anatomical traits are useful for identifying Lamiaceae taxa. Also, there is a need of upgradation and addition of studied taxa in flora of Pakistan comprehensively.


Assuntos
Lamiaceae , Folhas de Planta , Paquistão , Lamiaceae/anatomia & histologia , Lamiaceae/ultraestrutura , Folhas de Planta/anatomia & histologia , Folhas de Planta/ultraestrutura , Estômatos de Plantas/anatomia & histologia , Estômatos de Plantas/ultraestrutura , Microscopia Eletrônica de Varredura , Tricomas/anatomia & histologia , Tricomas/ultraestrutura , Epiderme Vegetal/anatomia & histologia , Epiderme Vegetal/ultraestrutura
3.
Biol Reprod ; 110(6): 1201-1212, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38767842

RESUMO

Determining egg quality is the foremost challenge in assisted reproductive technology (ART). Although extensive advances have been made in multiple areas of ART over the last 40 years, oocyte quality assessment tools have not much evolved beyond standard morphological observation. The oocyte not only delivers half of the nuclear genetic material and all of the mitochondrial DNA to an embryo but also provides complete developmental support during embryonic growth. Oocyte mitochondrial numbers far exceed those of any somatic cell, yet little work has been done to evaluate the mitochondrial bioenergetics of an oocyte. Current standard oocyte assessment in in vitro fertilization (IVF) centers include the observation of oocytes and their surrounding cell complex (cumulus cells) via stereomicroscope or inverted microscope, which is largely primitive. Additional oocyte assessments include polar body grading and polarized light meiotic spindle imaging. However, the evidence regarding the aforementioned methods of oocyte quality assessment and IVF outcomes is contradictory and non-reproducible. High-resolution microscopy techniques have also been implemented in animal and human models with promising outcomes. The current era of oocyte imaging continues to evolve with discoveries in artificial intelligence models of oocyte morphology selection albeit at a slow rate. In this review, the past, current, and future oocyte imaging techniques will be examined with the goal of drawing attention to the gap which limits our ability to assess oocytes in real time. The implications of improved oocyte imaging techniques on patients undergoing IVF will be discussed as well as the need to develop point of care oocyte assessment testing in IVF labs.


Assuntos
Oócitos , Oócitos/fisiologia , Humanos , Animais , Feminino , Fertilização in vitro/métodos , Técnicas de Reprodução Assistida
4.
Histochem Cell Biol ; 162(1-2): 3-12, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38609528

RESUMO

One hundred years ago, Robert Feulgen published a landmark paper in which he described the first method to stain DNA in cells and tissues. Although a century has passed since the discovery by Feulgen and Rossenbeck, the chemical reaction still exerts an important influence in current histochemical studies. Its contribution in diverse fields, spanning from biomedicine to plant biology, has paved the way for the most significant studies that constitute our current knowledge. The possibility to specifically explore the DNA in cell nuclei while quantifying its content makes it a contemporary and timeless method. Indeed, many histocytochemical studies following the 1924 paper have led to a deep understanding of genome organization in general as well as several specific mechanisms (e.g. DNA duplication or tumour pathology) that, nowadays, constitute some of the most fundamental pillars in biological investigations. In this review, we discuss the chemistry and application of the Feulgen reaction to both light and electron microscopy.


Assuntos
DNA , História do Século XX , Humanos , DNA/química , Animais , Corantes de Rosanilina
5.
J Anat ; 244(5): 873-881, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38111134

RESUMO

OBJECTIVES: The presence of prostate-specific antigen (PSA) in saliva and salivary glands has been reported. Nevertheless, its release pathway in these glands remains to be elucidated. Here, we showed PSA subcellular distribution focusing on its plausible route in human salivary parenchyma. MATERIALS AND METHODS: Sections of parotid and submandibular glands were subjected to the immunohistochemical demonstration of PSA by the streptavidin-biotin method revealed by alkaline phosphatase. Moreover, ultrathin sections were collected on nickel grids and processed for immunocytochemical analysis, to visualize the intracellular distribution pattern of PSA through the observation by transmission electron microscopy. RESULTS: By immunohistochemistry, in both parotid and submandibular glands PSA expression was detected in serous secretory acini and striated ducts. By immunocytochemistry, immunoreactivity was retrieved in the cytoplasmic compartment of acinar and ductal cells, often associated with small cytoplasmic vesicles. PSA labeling appeared also on rough endoplasmic reticulum and in the acini's lumen. A negligible PSA labeling appeared in most of the secretory granules of both glands. CONCLUSIONS: Our findings clearly support that human parotid and submandibular glands are involved in PSA secretion. Moreover, based on the immunoreactivity pattern, its release in oral cavity would probably occur by minor regulated secretory or constitutive-like secretory pathways.


Assuntos
Antígeno Prostático Específico , Glândulas Salivares , Humanos , Masculino , Imuno-Histoquímica , Glândula Parótida/ultraestrutura , Antígeno Prostático Específico/metabolismo , Glândulas Salivares/ultraestrutura , Glândula Submandibular/metabolismo
6.
Biopolymers ; : e23610, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953406

RESUMO

Structural nature of glucan chains in the amorphous part of granular starch was examined by iodine vapor treatment and lintnerization. Four iodine-stained amylose-containing normal starches and their waxy counterparts were examined under a microscope before, during, and after lintnerization. The presence of amylose retarded the lintnerization rate. The degree of retardation correlated with the structural type of the amylopectin component, suggesting that potato amylopectin (type 4 structure) interacts with amylose in the granules, whereas in barley granules (type 1 structure) the interaction is very weak. The inclusion complexes with iodine were not degraded by the acid treatment. Therefore, the iodine-glucan chain complex formation could be used to study the structural nature of the flexible, amorphous parts of the starch granules. Indeed, at the end of lintnerization, when 20%-30% of the granules remained, substantial amounts of blue-stained complexes were washed out from the granules especially from amylose-containing barley and maize starch, but also from both normal and waxy cassava and potato starch. The complexation with iodine did not affect the rate of lintnerization. This suggested that single helical structures were present during lintnerization also in the absence of iodine and this conformation was the reason for the acid resistance.

7.
J Microsc ; 294(3): 268-275, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38738847

RESUMO

Light microscopy facilities vary in the number of imaging systems and the scope of technologies they support. Each facility must craft an identity through the selection of equipment and development of staff in order to serve the needs of its local research environment. The process of crafting a light microscopy facility can be compared to curation of an art exhibition: great care should be given to the selection and placement of each object in order to make a coherent statement. Lay Description: Light microscopy facilities vary in the number of imaging systems and the scope of technologies they support. Each facility must develop an identity through the selection of equipment and development of staff in order to serve the needs of its local research environment. The process of crafting a light microscopy facility can be compared to curation of an art exhibition: great care should be given to the selection and placement of each object in order to make a coherent statement.

8.
J Microsc ; 295(2): 102-120, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38477035

RESUMO

Plants continuously face various environmental stressors throughout their lifetime. To be able to grow and adapt in different environments, they developed specialized tissues that allowed them to maintain a protected yet interconnected body. These tissues undergo specific primary and secondary cell wall modifications that are essential to ensure normal plant growth, adaptation and successful land colonization. The composition of cell walls can vary among different plant species, organs and tissues. The ability to remodel their cell walls is fundamental for plants to be able to cope with multiple biotic and abiotic stressors. A better understanding of the changes taking place in plant cell walls may help identify and develop new strategies as well as tools to enhance plants' survival under environmental stresses or prevent pathogen attack. Since the invention of microscopy, numerous imaging techniques have been developed to determine the composition and dynamics of plant cell walls during normal growth and in response to environmental stimuli. In this review, we discuss the main advances in imaging plant cell walls, with a particular focus on fluorescent stains for different cell wall components and their compatibility with tissue clearing techniques. Lay Description: Plants are continuously subjected to various environmental stresses during their lifespan. They evolved specialized tissues that thrive in different environments, enabling them to maintain a protected yet interconnected body. Such tissues undergo distinct primary and secondary cell wall alterations essential to normal plant growth, their adaptability and successful land colonization. Cell wall composition may differ among various plant species, organs and even tissues. To deal with various biotic and abiotic stresses, plants must have the capacity to remodel their cell walls. Gaining insight into changes that take place in plant cell walls will help identify and create novel tools and strategies to improve plants' ability to withstand environmental challenges. Multiple imaging techniques have been developed since the introduction of microscopy to analyse the composition and dynamics of plant cell walls during growth and in response to environmental changes. Advancements in plant tissue cleaning procedures and their compatibility with cell wall stains have significantly enhanced our ability to perform high-resolution cell wall imaging. At the same time, several factors influence the effectiveness of cleaning and staining plant specimens, as well as the time necessary for the process, including the specimen's size, thickness, tissue complexity and the presence of autofluorescence. In this review, we will discuss the major advances in imaging plant cell walls, with a particular emphasis on fluorescent stains for diverse cell wall components and their compatibility with tissue clearing techniques. We hope that this review will assist readers in selecting the most appropriate stain or combination of stains to highlight specific cell wall components of interest.


Assuntos
Parede Celular , Corantes Fluorescentes , Plantas , Células Vegetais/fisiologia , Coloração e Rotulagem/métodos
9.
J Microsc ; 294(2): 215-224, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38556727

RESUMO

Global efforts to minimise carbon dioxide emissions are also leading to attempts to use calcined clays (CC) as a partial substitute for cement in concrete. While the hydration mechanism of such CC blended cements is now well understood, the range of effective admixtures like polycarboxylate ethers (PCE) is limited. There are PCE types that promise relatively high effectiveness, but the mechanisms of action are not yet sufficiently understood. For a detailed understanding of the adsorption of such PCEs, spatially resolved studies of the binder were performed using a combination of fluorescence and scanning electron microscopy. In a comparison of two superplasticisers, the investigations have shown different sites of preferred adsorption in a CC blended system and the results can be correlated with flow tests and setting behaviour. The investigations have shown that a certain PCE type has a higher adsorption on CC and other components of a blended system in comparison to other types.

10.
J Microsc ; 295(2): 147-176, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38441305

RESUMO

This paper reports on the development of an open-source image analysis software 'pipeline' dedicated to petrographic microscopy. Using conventional rock thin sections and images from a standard polarising microscope, the pipeline can classify minerals and subgrains into objects and obtain information about optic-axis orientation. Five metamorphic rocks were chosen to test and illustrate the method. Thin sections were imaged using reflected and cross- and plane-polarised transmitted light. Images were taken at different angles of the polariser and analyser (360° with 10° steps), both with and without the full-lambda plate. The resulting image stacks were analysed with a modular pipeline for optic-axis mapping (POAM). POAM consists of external and internal software packages that register, segment, classify, and interpret the visible light spectra using object-based image analysis (OBIAS). The mapped fields-of-view and grain orientation stereonets of interest are presented in the context of whole-slide images. Two innovations are reported. First, we used hierarchical tree region merging on blended multimodal images to classify individual grains of rock-forming minerals into objects. Second, we assembled a new optical mineralogy algorithm chain that identifies the mineral slow axis orientation. The c-axis orientation results were verified with scanning electron microscopy electron backscattered diffraction (SEM-EBSD) data. For quartz (uniaxial) in a granite mylonite the test yielded excellent correspondence of c-axis azimuth and good agreement for inclination. For orthorhombic orthopyroxene in a deformed garnet harzburgite, POAM produced acceptable results for slow axis azimuth. In addition, the method identified slight anisotropy in garnet that would not be appreciated by traditional microscopy. We propose that our method is ideally suited for two commonly performed tasks in mineralogy. First, for mineral grain classification of entire thin sections scans on blended images to provide automated modal abundance estimates and grain size distribution. Second, for prospective fields of view of interest, POAM can rapidly generate slow axis crystal orientation maps from multiangle image stacks on conventionally prepared thin sections for targeting detailed SEM-EBSD studies.

11.
Connect Tissue Res ; 65(2): 117-132, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38530304

RESUMO

Osteoarthritis (OA) is a multifactorial joint disease characterized by articular cartilage degradation. Risk factors for OA include joint trauma, obesity, and inflammation, each of which can affect joint health independently, but their interaction and the associated consequences of such interaction were largely unexplored. Here, we studied compositional and structural alterations in knee joint cartilages of Sprague-Dawley rats exposed to two OA risk factors: joint injury and diet-induced obesity. Joint injury was imposed by surgical transection of anterior cruciate ligaments (ACLx), and obesity was induced by a high fat/high sucrose diet. Depth-dependent proteoglycan (PG) content and collagen structural network of cartilage were measured from histological sections collected previously in Collins et al.. (2015). We found that ACLx primarily affected the superficial cartilages. Compositionally, ACLx led to reduced PG content in lean animals, but increased PG content in obese rats. Structurally, ACLx caused disorganization of collagenous network in both lean and obese animals through increased collagen orientation in the superficial tissues and a change in the degree of fibrous alignment. However, the cartilage degradation attributed to joint injury and obesity was not necessarily additive when the two risk factors were present simultaneously, particularly for PG content and collagen orientation in the superficial tissues. Interestingly, sham surgeries caused a through-thickness disorganization of collagen network in lean and obese animals. We conclude that the interactions of multiple OA risk factors are complex and their combined effects cannot be understood by superposition principle. Further research is required to elucidate the interactive mechanism between OA subtypes.


Assuntos
Cartilagem Articular , Osteoartrite , Ratos , Animais , Ratos Sprague-Dawley , Articulação do Joelho/patologia , Osteoartrite/patologia , Proteoglicanas/metabolismo , Obesidade/metabolismo , Cartilagem Articular/patologia , Colágeno/metabolismo
12.
Ann Bot ; 133(2): 305-320, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38041589

RESUMO

BACKGROUND AND AIMS: Given the lack of specific studies on floral development in melon (Cucumis melo L.), we carried out an extensive study involving morphological and transcriptomic analyses to characterize floral development in this species. METHODS: Using an andromonoecious line, we analysed the development of floral buds in male and hermaphrodite flowers with both light microscopy and scanning electron microscopy. Based on flower lengths, we established a correlation between the developmental stages and four main episodes of floral development and conducted an extensive RNA sequencing analysis of these episodes. KEY RESULTS: We identified 12 stages of floral development, from the appearance of the floral meristems to anthesis. The main structural differences between male and hermaphrodite flowers appeared between stages 6 and 7; later stages of development leading to the formation of organs and structures in both types of flowers were also described. We analysed the gene expression patterns of the four episodes in flower development to find the genes that were specific to each given episode. Among others, we identified genes that defined the passage from one episode to the next according to the ABCDE model of floral development. CONCLUSIONS: This work combines a detailed morphological analysis and a comprehensive transcriptomic study to enable characterization of the structural and molecular mechanisms that determine the floral development of an andromonoecious genotype in melon. Taken together, our results provide a first insight into gene regulation networks in melon floral development that are crucial for flowering and pollen formation, highlighting potential targets for genetic manipulation to improve crop yield of melon in the future.


Assuntos
Cucurbitaceae , Cucurbitaceae/genética , Perfilação da Expressão Gênica/métodos , Flores , Reprodução , Genes Reguladores , Regulação da Expressão Gênica de Plantas
13.
Exp Cell Res ; 433(2): 113807, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37852350

RESUMO

Cellular biology research relies on microscopic imaging techniques for studying the complex structures and dynamic processes within cells. Fluorescence microscopy provides high sensitivity and subcellular resolution but has limitations such as photobleaching and sample preparation challenges. Transmission light microscopy offers a label-free alternative but lacks contrast for detailed interpretation. Deep learning methods have shown promise in analyzing cell images and extracting meaningful information. However, accurately learning and simulating diverse subcellular structures remain challenging. In this study, we propose a method named three-dimensional cell neural architecture search (3DCNAS) to predict subcellular structures of fluorescence using unlabeled transmitted light microscope images. By leveraging the automated search capability of differentiable neural architecture search (NAS), our method partially mitigates the issues of overfitting and underfitting caused by the distinct details of various subcellular structures. Furthermore, we apply our method to analyze cell dynamics in genome-edited human induced pluripotent stem cells during mitotic events. This allows us to study the functional roles of organelles and their involvement in cellular processes, contributing to a comprehensive understanding of cell biology and offering insights into disease pathogenesis.


Assuntos
Células-Tronco Pluripotentes Induzidas , Humanos , Organelas , Microscopia de Fluorescência/métodos
14.
BMC Vet Res ; 20(1): 310, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992617

RESUMO

The present investigation examined the oropharyngeal roof of two turtles having different feeding behaviors: the landform Greek tortoise (Testudo graeca graeca) primarily herbivores and the semi-aquatic red-eared slider turtle (Trachemys scripta elegans) lives in freshwater that opportunistic omnivorous grossly and by scanning and light microscopes. Grossly, the Greek tortoise had a V-shaped roof consisting of the upper rhamphotheca, peri-palatine region, upper alveolar ridge, peripheral palatine ridge, median palatine ridge, vomer, choanae, caudal palatine part, and pharynx. At the same time, the red-eared slider had a semilunar roof consisting of upper rhamphotheca, two peripheral palatine ridges, core of palatine ridges, upper alveolar band, vomer, choanae, caudal palatine part, and pharynx. SEM revealed that the red-eared slider roof appeared more straightforward. The upper rhamphotheca is sharp, with a median premaxillary notch in the red-eared slider that gives a powerful bite for cutting to compensate absence of the teeth. Additionally, the red-eared slider's upper alveolar band is interrupted by a single upper alveolar ridge that appears spiky, pointed, and longer as it needs powerful chewing of prey and there are two types of teeth-like projections at its peri-palatine area for food-crushing and chewing. The Greek tortoise palatine region had numerous ridges and folds to provide roughness for food processing. Greek tortoises had small-sized choanae with two choanal folds to minimize choanal openings when eating dusty grasses. Histologically, Greek tortoise palate was rostrally thicker and more keratinized than caudally, and the caudal palatine region was characterized by a single pair of circumvallate-like papilla with multiple mucous openings and secretions, while red-eared slider palate was slightly keratinized at the peri-choanal region, and the rest of the palate was non-keratinized with few mucous openings. The current investigation found various structural oropharyngeal roof adaptations to feeding behavior in the omnivore red-eared slide compared to the herbivorous Greek turtle.


Assuntos
Comportamento Alimentar , Orofaringe , Tartarugas , Animais , Tartarugas/anatomia & histologia , Orofaringe/anatomia & histologia , Microscopia Eletrônica de Varredura/veterinária
15.
BMC Vet Res ; 20(1): 367, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39148099

RESUMO

BACKGROUND: Recurrent dehydration causes chronic kidney disease in humans and animal models. The dromedary camel kidney has remarkable capacity to preserve water and solute during long-term dehydration. In this study, we investigated the effects of dehydration and subsequent rehydration in the camel's kidney histology/ultrastructure and changes in aquaporin/solute carrier proteins along with gene expression. RESULTS: In light microscopy, dehydration induced few degenerative and necrotic changes in cells of the cortical tubules with unapparent or little effect on medullary cells. The ultrastructural changes encountered in the cortex were infrequent during dehydration and included nuclear chromatin condensation, cytoplasmic vacuolization, mitochondrial swelling, endoplasmic reticulum/ lysosomal degeneration and sometimes cell death. Some mRNA gene expressions involved in cell stability were upregulated by dehydration. Lesions in endothelial capillaries, glomerular membranes and podocyte tertiary processes in dehydrated camels indicated disruption of glomerular filtration barrier which were mostly corrected by rehydration. The changes in proximal tubules brush borders after dehydration, were accompanied by down regulation of ATP1A1 mRNA involved in Na + /K + pump that were corrected by rehydration. The increased serum Na, osmolality and vasopressin were paralleled by modulation in expression level for corresponding SLC genes with net Na retention in cortex which were corrected by rehydration. Medullary collecting ducts and interstitial connective tissue were mostly unaffected during dehydration. CKD, a chronic nephropathy induced by recurrent dehydration in human and animal models and characterized by interstitial fibrosis and glomerular sclerosis, were not observed in the dehydrated/rehydrated camel kidneys. The initiating factors, endogenous fructose, AVP/AVPR2 and uric acid levels were not much affected. TGF-ß1 protein and TGF-ß1gene expression showed no changes by dehydration in cortex/medulla to mediate fibrosis. KCNN4 gene expression level was hardly detected in the dehydrated camel's kidney; to encode for Ca + + -gated KCa3.1 channel for Ca + + influx to instigate TGF-ß1. Modulation of AQP 1, 2, 3, 4, 9 and SLC protein and/or mRNAs expression levels during dehydration/rehydration was reported. CONCLUSIONS: Long-term dehydration induces reversible or irreversible ultrastructural changes in kidney cortex with minor effects in medulla. Modulation of AQP channels, SLC and their mRNAs expression levels during dehydration/rehydration have a role in water conservation. Cortex and medulla respond differently to dehydration/rehydration.


Assuntos
Aquaporinas , Camelus , Desidratação , Rim , Animais , Desidratação/veterinária , Aquaporinas/metabolismo , Aquaporinas/genética , Rim/patologia , Rim/metabolismo , Masculino , Hidratação/veterinária , Regulação da Expressão Gênica , Proteínas de Transporte/metabolismo , Proteínas de Transporte/genética
16.
Microsc Microanal ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39132805

RESUMO

This study examines the egg-laying behavior and egg morphology of Hydrometra stagnorum (Linnaeus, 1753) (Gerromorpha: Heteroptera) to provide ecofaunistic information about the species. Newly recorded H. stagnorum samples were collected from the Karabük province of Western Black Sea region of Türkiye. Physicochemical parameters of the water were also recorded. The morphology and egg-laying behavior of H. stagnorum eggs were identified using a stereo, light and electron microscopy. Mature eggs were observed to be blackish dark brown in color. The study reveals distinctive characteristics of the egg structure and micropyle areas, which may contribute to the classification of the species at the subfamily level. Additionally, it was found that H. stagnorum inhabits high-quality waters.

17.
Anaerobe ; 86: 102822, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38341023

RESUMO

Microscopic technologies including light and fluorescent, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and cryo-electron microscopy have been widely utilized to visualize Clostridioides difficile at the molecular, cellular, community, and structural biology level. This comprehensive review summarizes the microscopy tools (fluorescent and reporter system) in their use to study different aspects of C. difficile life cycle and virulence (sporulation, germination) or applications (detection of C. difficile or use of antimicrobials). With these developing techniques, microscopy tools will be able to find broader applications and address more challenging questions to study C. difficile and C. difficile infection.


Assuntos
Clostridioides difficile , Clostridioides difficile/ultraestrutura , Humanos , Microscopia/métodos , Infecções por Clostridium/microbiologia , Infecções por Clostridium/diagnóstico
18.
Molecules ; 29(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38893505

RESUMO

Cynometra iripa Kostel. is a Fabaceae species of mangrove used in traditional Ayurvedic medicine for treating inflammatory conditions. The present study aims to establish monographic botanical and chemical quality criteria for C. iripa leaf and bark as herbal substances and to evaluate their in vitro antioxidant potential. Macroscopic and microscopic qualitative and quantitative analyses, chemical LC-UV/DAD-ESI/MS profiling, and the quantification of key chemical classes were performed. Antioxidant activity was evaluated by DPPH and FRAP assays. Macroscopically, the leaf is asymmetrical with an emarginated apex and cuneate base. Microscopically, it shows features such as two-layered adaxial palisade parenchyma, vascular bundles surrounded by 3-6 layers of sclerenchyma, prismatic calcium oxalate crystals (5.89 ± 1.32 µm) along the fibers, paracytic stomata only on the abaxial epidermis (stomatal index-20.15), and non-glandular trichomes only on petiolules. The microscopic features of the bark include a broad cortex with large lignified sclereids, prismatic calcium oxalate crystals (8.24 ± 1.57 µm), and secondary phloem with distinct 2-5 seriated medullary rays without crystals. Chemical profile analysis revealed that phenolic derivatives, mainly condensed tannins and flavonoids, are the main classes identified. A total of 22 marker compounds were tentatively identified in both plant parts. The major compounds identified in the leaf were quercetin-3-O-glucoside and taxifolin pentoside and in the bark were B-type dimeric proanthocyanidins and taxifolin 3-O-rhamnoside. The total phenolics content was higher in the leaf (1521 ± 4.71 mg GAE/g dry weight), while the total flavonoids and condensed tannins content were higher in the bark (82 ± 0.58 mg CE/g and 1021 ± 5.51 mg CCE/g dry weight, respectively). A total of 70% of the hydroethanolic extracts of leaf and bark showed higher antioxidant activity than the ascorbic acid and concentration-dependent scavenging activity in the DPPH assay (IC50 23.95 ± 0.93 and 23.63 ± 1.37 µg/mL, respectively). A positive and statistically significant (p < 0.05) correlation between the phenol content and antioxidant activity was found. The results obtained will provide important clues for the quality control criteria of C. iripa leaf and bark, as well as for the knowledge of their pharmacological potential as possible anti-inflammatory agents with antioxidant activity.


Assuntos
Antioxidantes , Casca de Planta , Extratos Vegetais , Folhas de Planta , Casca de Planta/química , Folhas de Planta/química , Antioxidantes/farmacologia , Antioxidantes/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Flavonoides/química , Flavonoides/análise , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/análise , Medicina Herbária/métodos , Fenóis/análise , Fenóis/química , Proantocianidinas/química , Proantocianidinas/análise , Proantocianidinas/farmacologia
19.
Epidemiol Prev ; 48(3): 249-253, 2024.
Artigo em Italiano | MEDLINE | ID: mdl-38995139

RESUMO

The presence of asbestos in cosmetic talc has been reported in the United States since the 1970s. The present article first retraces the Italian case, then focuses on technical features as well as the relevant laws, rules, and regulations, ending with a precautionary evidence-based approach. Research was mainly aimed at retrieving official Italian Health Authority papers on the tests carried out several decades ago, to identify the presence of any asbestos in talc of products for sale. Results show that, in Italy, National Institute of Health (the technical agency of the Ministry of Health) and the Italian Pharmacopoeia (1985) used scanning electron microscopy (SEM) to ascertain the absence of asbestos fibres, following positive identification in several samples they had analysed. In 2008, Italy adopted the EU Pharmacopoeia according to which light microscopy (LM) was sufficient for analysis. Such a technical downgrading clearly went - and goes - against the standard principle of precaution to prevent harm to users' health.Unfortunately, documents on the above-mentioned SEM research that would have contextualized observations were not recovered from the Italian State Archive. Observations and results indicate that in practice levels of attention on the issue underwent a considerable (negative) decline, so much that effective planning of the necessary controls was not possible, which is unfortunately true to this day. Final comments deal with the principle of precaution and possible practical operational solutions.


Assuntos
Amianto , Cosméticos , Itália , Humanos , Talco , Microscopia Eletrônica de Varredura , Medição de Risco
20.
Arkh Patol ; 86(2): 42-50, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38591906

RESUMO

Vasoproliferative retinal tumor (VPT) is a term proposed by ophthalmologists in relation to the totality of manifestations of an intraocular volumetric process with involvement of the inner lining of the eye, an integral part of which is the active growth of blood vessels. The available literature data on the morphology of this process are very contradictory and ambiguous. The article presents two clinical cases of vasoproliferative retinal tumor with own illustration of morphological studies.


Assuntos
Retina , Neoplasias da Retina , Humanos , Retina/patologia , Neoplasias da Retina/genética , Neoplasias da Retina/patologia
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