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Background: Mast cells have been implicated in the pathology of various urinary bladder disorders. However, the distribution of mast cells throughout urinary bladder tissue remains uncertain despite mast cell prevalence being relatively well-defined. Using a mouse tissue model, this study aims to characterise the prevalence and distribution of mast cells throughout the urinary bladder., Methods: Bladder tissues were collected from six C57BL/6J female mice. Mast cell prevalence was quantified by flow cytometry, based on the expression of the following characteristic markers: CD45, CD117 and FcɛRIα. The toluidine blue stain assessed mast cell distribution, size, and proximity to vasculature. A repeated measures one-way ANOVA was used to evaluate the density of mast cells between the discrete layers of the urinary bladder, and an ordinary one-way ANOVA was used to assess potential differences between mast cell size across the urinary bladder wall., Results: It was determined that mast cells compose less than 4% of all live leukocytes in the urinary bladder. They were also found to be more prominent in the lamina propria and detrusor muscle layers, compared to the urothelium and adventitia. In addition, 20.89% of mast cells were located near vasculature, which may be an important factor in consideration of their function and potential to contribute to various bladder pathologies, such as cystitis or overactive bladder., Conclusion: These findings provide a baseline understanding of mast cell prevalence and distribution throughout the urinary bladder., (© 2024. The Author(s).)

Mast cells play an important role in the body defense against allergens, pathogens, and parasites by participating in inflammation development. However, there is evidence for their contributing to the pathogenesis of a number of atopic, autoimmune, as well as cardiovascular, oncologic, neurologic, and other diseases (allergy, asthma, eczema, rhinitis, anaphylaxis, mastocytosis, multiple sclerosis, rheumatoid arthritis, inflammatory gastrointestinal and pulmonary diseases, migraine, etc.). The diagnosis of many diseases and the study of mast cell functions in health and disease require their identification; so, the knowledge on adequate imaging techniques for mast cells in humans and different species of animals is of particular importance. The present review summarizes the data on major methods of mast cell imaging: enzyme histochemistry, immunohistochemistry, as well as histochemistry using histological stains. The main histological stains bind to heparin and other acidic mucopolysaccharides contained in mast cells and stain them metachromatically. Among these are toluidine blue, methylene blue (including that contained in May-Grünwald-Giemsa stain), thionin, pinacyanol, and others. Safranin and fluorescent dyes: berberine and avidin - also bind to heparin. Longer staining with histological dyes or alcian blue staining is needed to label mucosal and immature mast cells. Advanced techniques - enzyme histochemistry and especially immunohistochemistry - enable to detect mast cells high-selectively using a reaction to tryptases and chymases (specific proteases of these cells). In the immunohistochemical study of tryptases and chymases, species-specific differences in the distribution of the proteases in mast cells of humans and animals should be taken into account for their adequate detection. The immunohistochemical reaction to immunoglobulin E receptor (FcεRI) and c-kit receptor is not specific to mast cells, although the latter is important to demonstrate their proliferation in normal and malignant growth. Correct fixation of biological material is also discussed in the review as it is of great significance for histochemical and immunohistochemical mast cell detection. Fluorescent methods of immunohistochemistry and a multimarker analysis in combination with confocal microscopy are reported to be new technological approaches currently used to study various mast cell populations., Competing Interests: Conflicts of interest. The authors declare no conflicts of interest related to the present study.

Context: Breast cancer constitutes nearly one third of cancers among women. Immune responses caused by neoplastic cells lead to the accumulation of inflammatory cells like mast cells (MCs), macrophages, lymphocytes, and plasma cells around the tumor tissue forming the tumor microenvironment., Aim: The study aims at quantifying the role of MCs in different grades of invasive carcinoma of breast with respect to estrogen receptor (ER), progesterone receptor (PR), and Human Epidermal growth factor Receptor 2 (HER2/neu)., Materials and Methods: This study included 60 cases of invasive carcinoma of breast. Toluidine blue staining was used for quantitative MC analysis and correlated with immunohistochemistry analysis for hormonal markers' positivity-ER, PR and HER2/neu., Results: The mean age was 52 years (range: 25-75 years). The average number of MCs in Grade I, II, and III were 24.05, 18.4, and 7.9, respectively, with a significant P value. ER, PR, and HER2/neu positivity was found in 60%, 55%, and 32% of the cases, respectively. ER positivity with mean MC count of 23.55 was found in 36 cases, and 33 cases were positive for PR with a mean MC count of 24.18 and a significant P value. HER2 positive cases were 28 with a mean MC count of 20.82., Conclusion: The presence of MCs in breast cancer is inversely proportional to the grade of tumor, i.e., a maximum number of MCs were seen in low grade tumors. In addition, there is a positive correlation between ER and PR receptor positivity with the presence of MCs in the stroma of breast cancer.

Mast cells are large cells with granular cytoplasm that participate in wound healing, angiogenesis and defense against pathogens. They also contribute to inflammation by initiating innate and acquired immunity. The granules of these cells exhibit characteristic staining properties. We investigated toluidine blue, astra blue, Alcian blue-pyronin Y and May-Grunwald Giemsa stains for mast cells in various oral lesions and assessed the efficacy of each for identifying mast cells. Sections were obtained from 10 each of diagnosed cases of inflammatory fibrous hyperplasia, periapical cyst, mild dysplasia, oral submucous fibrosis and oral squamous cell carcinoma and stained using the stains listed above. Mast cells were assessed for their presence, contrast of the mast cell in the connective tissue background and number. We found that May-Grunwald Giemsa stain was the best for identification of mast cells, although toluidine blue staining is less time-consuming. Overall we obtained better results using May-Grunwald Giemsa and toluidine blue for staining mast cells.

Mast cells are part of the immune system and characteristically contain histamine- and heparin-rich basophilic granules. While these cells are usually associated with allergy and anaphylaxis, they also promote wound healing and angiogenesis and confer protection against pathogens. The presence of these cells is sometimes indicative of a poor prognosis, especially in skin cancer, pancreatic cancer, and lymphoma. Toluidine blue staining of acid-fast granules is an established method for the identification and quantification of mast cells. Generating detailed information on the location of mast cells within tissues is problematic using this technique and often requires serial sections from adjacent tissue to be separately stained with hematoxylin and eosin (H&E). Staining serial sections is not always possible, particularly if the sample is very small or rare. In such cases, a method of simultaneously identifying and localizing mast cells in a tissue would be advantageous. Toluidine blue and H&E are not commonly combined because H&E includes repetitive washes in water, which may affect the efficacy of the aqueous-soluble toluidine blue. We have developed and tested a novel staining technique that integrates toluidine blue between hematoxylin and eosin in one simple procedure. This protocol works on both frozen and formalin-fixed, paraffin-embedded tissue and readily allows for the identification of purple-stained mast cells against a clean H&E background. This facilitates a more accurate localization and proper counting of mast cells in normal and affected tissue.

Mast cells (MCs) play a major role in allergic reactions. Surprisingly, the acupuncture points have a higher density of MCs compared with nonacupoints in the skin, which is consistent with the augmentation of the immune function by acupuncture treatment. We hypothesized that the primo vascular system (PVS), which was proposed as the anatomical structure of the acupuncture points and meridians, should have a high density of MCs. In order to test that hypothesis, we investigated the primo nodes isolated from the surfaces of internal organs, such as the liver, the small and the large intestines, and the bladder. The harvested primo nodes were stained with toluidine blue, and the MCs were easily recognized by their red-purple stains and their characteristic granules. The results showed a high density of MCs in the primo nodes and confirmed the hypothesis. The MCs were uniformly distributed in the nodes. The relative concentration of the MCs with respect to other cells was ∼15%. We divided the sizes of the primo nodes into three classes: large, medium, and small. The number density and the relative concentration of MCs did not show a size-dependence. The current work suggests that the PVS may participate in the immune response to allergic inflammation, which closely involves MCs., (Copyright © 2015. Published by Elsevier B.V.)

This is the first study to describe the subtypes, number and distribution of mast cells (MC) in cat tongue by histochemical and immunohistochemical methods. Six male adult felines' tongue tissue samples consist of the study's material. Samples were fixed in 10% formaldehyde. MC number and distribution in the feline tongue were assessed using toluidine blue. Also, sections taken from blocks were stained in alcian blue/safranin O (AB/SO) combined dyes to determine the MC subtypes. The Streptavidin biotin complex method using anti‐chymase and anti‐tryptase primary antibodies was used for immunohistochemistry. Metachromatic MCs were mainly observed in the lamina propria close to the multilayered keratinized stratified squamous epithelium. The high number of MCs in this region may be because the dorsal surface of the tongue plays an essential role in the defence system of tongue tissue and, thus, of the body as a whole. Additionally, the number of MCs stained with AB (+) (1.7 ± 0.08) in the feline tongue was statistically higher than those with SO (+) (0.18 ± 0.02). This might be interpreted as an indication that MC heterogeneity may be due not only to their staining properties but also to their localization. It is also conceivable that the high histamine content may be a factor in this. Tryptase‐positive MCs were found in the loose connective tissue around blood vessels, between the glands, as solitary cells, or in groups of several cells. Chymase‐positive MCs were observed more individually rather than in groups. Moreover, chymase‐positive MCs were detected to be located in the filiform papillae subepithelial and in the blood vessels' immediate vicinity. Animals often lick themselves to clean themselves and promote healing. For this reason, it is very important to protect the tongue, which is in direct contact with the external environment, against foreign agents. Considering both the functional and protective properties of the tongue, we concluded that MCs may play a role in oral cavity immunity and protective effect. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the antihistaminic potential of the plant extract from Lannea coromandelica using both in vitro and in vivo models. In vitro antihistaminic effects were studied using isolated guinea pig ileum to assess dose-dependent inhibitory impacts on histamine-induced contractions. Mast cell density was evaluated using a mast cell count model, calculating the average number of mast cells per unit area in the mesentery. For in vivo assessments, a histamine aerosol-induced bronchospasm model in guinea pigs was used, where pre-convulsive dyspnea (PCD) onset time was noted as pre-convulsive time (PCT). Additionally, a clonidine-induced mast cell degranulation model in rats was employed, with cells stained using 1% toluidine blue to count intact and degranulated mast cells. The Lannea coromandelica extract exhibited a dose-dependent inhibition of histamineinduced contractions in isolated guinea pig ileum. Similarly, the extract inhibited mast cell degranulation in a dosedependent manner, with a higher dose of 400 mg/kg proving more effective than a lower dose of 200 mg/kg. Acute toxicity studies confirmed the safety of the extract at moderate doses, revealing no toxic symptoms at a dosage of 2000 mg/kg body weight. Importantly, the extract significantly increased PCT in guinea pigs and reduced the percentage of disrupted mast cells induced by clonidine. Lannea coromandelica shows promising antihistaminic properties, effectively inhibiting histamine-induced bronchospasm and mast cell degranulation, which can be an option for the development of antiasthmatic drugs. [ABSTRACT FROM AUTHOR]

Objective and design: Mast cells (MCs), as the fastest immune responders, play a critical role in the progression of neuroinflammation-related diseases, especially in depression. Quercetin (Que) and kaempferol (Kae), as two major diet-derived flavonoids, inhibit MC activation and exhibit significant antidepressant effect due to their anti-inflammatory capacity. The study aimed to explore the mechanisms of inhibitory effect of Que and Kae on MC activation, and whether Que and Kae suppress hippocampal mast cell activation in LPS-induced depressive mice. Subjects and treatment: In vitro assays, human mast cells (HMC-1) were pretreated with Que or Kae for 1 h, then stimulated by phorbol 12-myristate 13-acetate (PMA) and 2,5-di-t-butyl-1,4-benzohydroquinone (tBHQ) for 3 h or 12 h. In vivo assays, Que or Kae was administered by oral gavage once daily for 14 days and then lipopolysaccharide (LPS) intraperitoneally injection to induce depressive behaviors. Methods: The secretion and expression of TNF-α were determined by ELISA and Western blotting. The nuclear factor of activated T cells (NFAT) transcriptional activity was measured in HMC-1 stably expressing NFAT luciferase reporter gene. Nuclear translocation of NFATc2 was detected by nuclear protein extraction and also was fluorescently detected in HMC-1 stably expressing eGFP-NFATc2. We used Ca2+ imaging to evaluate changes of store-operated calcium entry (SOCE) in HMC-1 stably expressing fluorescent Ca2+ indicator jGCamP7s. Molecular docking was used to assess interaction between the Que or Kae and calcium release-activated calcium modulator (ORAI). The hippocampal mast cell accumulation and activation were detected by toluidine blue staining and immunohistochemistry with β-tryptase. Results: In vitro assays of HMC-1 activated by PtBHQ (PMA and tBHQ), Que and Kae significantly decreased expression and secretion of TNF-α. Moreover, NFAT transcriptional activity and nuclear translocation of NFATc2 were remarkably inhibited by Que and Kae. In addition, the Ca2+ influx mediated by SOCE was suppressed by Que, Kae and the YM58483 (ORAI inhibitor), respectively. Importantly, the combination of YM58483 with Que or Kae had no additive effect on the inhibition of SOCE. The molecular docking also showed that Que and Kae both exhibit high binding affinities with ORAI at the same binding site as YM58483. In vivo assays, Que and Kae significantly reversed LPS-induced depression-like behaviors in mice, and inhibited hippocampal mast cell activation in LPS-induced depressive mice. Conclusions: Our results indicated that suppression of SOCE/NFATc2 pathway-mediated by ORAI channels may be the mechanism of inhibitory effect of Que and Kae on MC activation, and also suggested Que and Kae may exert the antidepressant effect through suppressing hippocampal mast cell activation. [ABSTRACT FROM AUTHOR]

Mast cell tumour is one of the most common cutaneous neoplasms in dogs, ranging from well differentiated to aggressive tumors with metastases. Currently, prognosis and therapeutic definitions of canine cutaneous MCTs are based on the histological grade of malignancy. Clinical examination and treatment were performed in Dnipro veterinary clinics and pathological analysis in the Department of Animal Anatomy, Histology and Pathomorphology, Dnipro State Agrarian and Economic University (Dnipro, Ukraine). Thirty-six dogs with a history of skin neoplasia were examined. Skin MCTs were diagnosed in 23 males and 13 females, aged between 5 and 15 years. No breed predisposition was found out in tested cohort. MCTs were located on the trunk (44.4%), limbs (33.4%) and less frequently on the head and neck, axillary, inguinal and perineal areas (22.2%). MCT was detected in 8 animals where the malignancy was systemic and develops metastatic spread to internal organs. Pathological diagnosis included cytopathological examination of tumor material, pathological analysis of samples obtained by incisional biopsy using haematoxylin/eosin and toluidine blue staining. According to the diagnostic criteria (smear cellularity, presence of cells with basophilic cytoplasmic granularity, size and number of cytoplasmic granules, presence or absence of mitotic figures, nuclear pleomorphism, presence or absence of binucleations or multinucleations, anisokaryosis), benign mast cell tumour (high grade) was diagnosed in 23 animals and malignant mast cell tumour (low grade) in 13 animals. These results were confirmed by histopathological methods using haematoxylin and eosin staining. Additional staining of histological sections with toluidine blue allowed differentiation of benign mast cell tumours into high-grade (38.9%) and intermediate-grade (5%). [ABSTRACT FROM AUTHOR]

Role of mast cells in various phases of skin wound healing is well reported in literature. However, there is much controversy about the importance of mast cells in skin wound repair. Few studies have demonstrated the presence of mast cells in skin wound repair in middle-aged and senescent individuals. The mast cells are resident cells in the skin and participate in the inflammatory process and wound repair response. It is known that there are major changes in the immune system with aging, including in the skin. In this work, we evaluated the density and maturation of mast cells (mature, intermediate and immature) at the edges of skin wounds in young, middle-aged and senescent mice by toluidine blue and alcianine-safranin blue staining. We found that there is a significant decrease in mast cells in senescent mice. There is a predominance of immature mast cells at all ages 5 days after injury. But the data are intriguing, as in senescent mice there are fewer mature mast cells. Further studies should be carried out to understand the role of mast cells during aging. [ABSTRACT FROM AUTHOR]

Objective：To compare the effects of three main active components of cortex dictamni namely obacunone，dictamnine， and fraxinellone，in the treatment of atopic dermatitis (AD) and explore their mechanisms. Methods：The AD mouse model was established using 2，4 ⁃ dinitrofluorobenzene (DNFB) ，and the effects of ethanol extract of cortex dictamni，obacunone，dictamnine， fraxinellone，and dexamethasone on chronic itch induced by AD in mice were observed. The severity degree of skin lesions in mice was evaluated using a skin lesion scoring system. Hematoxylin ⁃ eosin (HE) and toluidine blue staining were used to evaluate epidermal thickness and mast cell count in mice. Enzyme⁃linked immunosorbent assay (ELISA) was used to detect the levels of interleukin (IL) ⁃4， IL ⁃31，and IL ⁃10 in mouse skin lesions. Western blot was used to detect the protein levels of Janus kinase (JAK1) ，phosphorylated JAK1 (p ⁃ JAK1) ，signal transducer and activator of transcription (STAT) 3，p ⁃ STAT3，STAT6 and p ⁃ STAT6. Results：Chronic itch induced by AD in mice was significantly inhibited by the ethanol extract of cortex dictamni. Compared with the model group，two of the three main active componentsof Cortex dictamni，namely dictamnine and fraxinellone，significantly inhibited the chronic itch induced by AD in mice，improved skin lesion symptoms and inflammatory cell infiltration，downregulated the levels of IL ⁃ 4 and IL ⁃ 31， upregulated the levels of IL⁃10，and inhibited the JAK1⁃STAT3/STAT6 signaling pathway. However，there was no significant difference between the obacunone group and the model group. Conclusion：Dictamnine and fraxinellone may be the main active components of cortex dictamnitoin exerting anti⁃dermatitis effect. [ABSTRACT FROM AUTHOR]

Background: The pathogenesis of prurigo nodularis (PN) is considered to be multifactorial, with numerous cells and cytokines confabulating to produce an aberrant immune response. Methods: A cross‐sectional observational study was done in cases of untreated primary prurigo nodularis cases with histopathological assessment in 49 cases from lesional and nonlesional skin with assessment of epidermal and dermal changes, dermal infiltrate, S‐100 and toluidine blue staining to assess the expression of nerve and mast cells. Results: The most common histological changes seen in lesional skin were hyperkeratosis (98%), irregular hyperplasia (69.4%), hypergranulosis (69.4%), subepidermal clefting (6%), vertical collagen bundles (51.0%), and dermal fibrosis (48.9%). Chronic inflammatory infiltrate was seen in all cases (100%) predominantly of lymphocytes (100%) followed by eosinophils (18.4%), plasma cells (8.2%), and neutrophils (2.0%). There was a marked increase in the expression of S‐100 (6.92 ± 3.40 vs. 3.94 ± 2.15, P < 0.001) and toluidine blue (4.99 ± 4.47 vs. 1.22 ± 1.28, P < 0.001) in the lesional skin as compared to the nonlesional skin. Conclusion: We can infer that the epidermal and dermal pathology in PN is related to the infiltrate of lymphocytes, mast cells, and neural hyperplasia which perpetuate the pathogenesis by triggering the itch‐inflammation cycle. Thus, apart from immunosuppressive agents that target lymphocytes and their cytokines, therapy targeted at mast cells and neural proliferation may be needed to treat prurigo nodularis. [ABSTRACT FROM AUTHOR]

Structural and functional parameters of mast cells (MC) in rat mammary glands during experimentally provoked breast cancer were studied by the cytogram, index of cell saturation with secretory products, and degranulation index. The cytogram was calculated in histological sections stained with toluidine blue. The functional conditions of MC were determined by electron microscopy. The study revealed expansion of MC population and activation of their functional state evidenced by significant prevalence of cells with high degranulation degree and reduced saturation index. At the ultrastructural level, MC were characterized by deformation, polymorphism, paleness of secretory granules, and elevation of the number of lacunae in the cytoplasm. The study showed that MC are active players in tumor microenvironment. Remembering heteromorphism of MC, further study of their role in pathogenesis of various tumor diseases seems promising. [ABSTRACT FROM AUTHOR]

The recent findings showed that the superficial fascia is a fibrous layer in the middle of hypodermis, richly innervated and vascularized, and more complex than so far demonstrated. This study showed the presence of mast cells in the superficial fascia of the human abdomen wall of three adult volunteer patients (mean age 42 ± 4 years; 2 females, 1 male), by Toluidine Blue and Safranin-O stains and Transmission Electron Microscopy. Mast cells are distributed among the collagen bundles and the elastic fibers, near the vessels and close to the nerves supplying the tissue, with an average density of 20.4 ± 9.4/mm2. The demonstration of the presence of mast cells in the human superficial fascia highlights the possible involvement of the tissue in the inflammatory process, and in tissue healing and regeneration processes. A clear knowledge of this anatomical structure of the hypodermis is fundamental for a good comprehension of some fascial dysfunctions and for a better-targeted clinical practice. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the influence of IR (λ850 ± 10 nm) and violet (λ405 ± 10 nm) LED phototherapy on total mast cells counts and its ability to influence mast cell degranulation. For this, 27 Wistar rats were used and were randomly distributed into three groups: control, IR LED, and violet LED. When indicated, irradiation done and they were sacrificed, had their tongue removed immediately, 20-min, 45-min, and 2-h after irradiation. Samples were processed to wax, cut, and stained with Toluidine Blue. Intact and degranulated mast cells were counted under light microscopy, and statistical analysis was carried out. In the superficial connective tissue and muscular tissues, violet LED light caused a significant increase in both total number and degranulated mast cells when compared to the control group immediately after irradiation. The degranulation indexes were higher in the groups irradiated with Violet light, both in superficial connective tissue and muscular tissues in relation to the timing. Irradiation with IR LED caused immediate increase in the total number and degranulated of mast cells when compared to the control group only in the superficial connective tissue. In all times observed, the highest total amount of mast cells was seen immediately after irradiation, except in the muscular tissue, which presented the highest amount after 20-min. It was concluded that IR and violet LED light were able to increase the number of mast cells and inducing degranulation in oral mucosa. However, considering that violet LED light can be harmful in periodontal disease, it seems that the use of IR LED light could be the best option in Dentistry. [ABSTRACT FROM AUTHOR]

Mast cells and the mediators they release play a major role in the pathogenesis of lung diseases. They regulate the function of the smooth muscle layer of the pulmonary airways and the same layer of the blood vessels. There are no data about the distribution of metachromatic and tryptase-positive mast cells in the blood vessels' wall as well as on the content of ghrelin in mast cell granules in rat's lung. The aim of this research was to present an analysis of the number and localisation of tryptasepositive, ghrelin-positive and metachromatic mast cells in the blood vessels (arteries, capillaries, venules and veins) in rats of different age. Six male Wistar rats were used for each age group? 20 days, 3 months and 1 year. Tissue slices for histochemical examination were taken from the caudal lobe of the left lung and stained with toluidine blue. Immunohistochemical reactions were then performed to indicate the expression of tryptase and ghrelin, allowing comparing the presence of tryptase-, ghrelin-positive and metachromatic mast cells in the wall of the blood vessels of different diameters. The light microscopical study showed that in all types of blood vessels from the three age groups, the number of ghrelin positive cells was the largest, followed by tryptase-positive and metachromatic mast cells. The observed differences in the distribution of these cells are important for maintaining the lung homeostasis and can be used as reference values in experimental studies in order to obtain accurate results. [ABSTRACT FROM AUTHOR]

Detailed mast cell classification is reported in humans and rats, however such classification is not available in porcine common hepatic duct. It is interesting to find out whether mast cells in common hepatic duct are able to produce ghrelin, which is involved in a series of biological functions including regulation of food intake, body weight, gastrointestinal motility, hormone secretion, glucose release, cardiovascular functions, enzyme release, cell proliferation and reproduction in pigs. Because the determination of the cellular mechanisms responsible for normal and pathological biliary tract motility is difficult in humans, swine appears to be one of the most suitable animal model for physiological and morphological studies related to ghrelin peptide. The lack of information about the distribution of mast cells in the wall of common hepatic duct (Ductus hepaticus communis) in domestic swine motivated us to undertake this study in order to gain a better understanding of ghrelin peptide. The aim of this study was to define the localisation and number of tryptase-, ghrelin- and toluidine blue positive mast cells in the layers of porcine common hepatic duct. In this respect, the immunohistochemical staining for detection of tryptase and ghrelin expression was performed. The toluidine blue staining allowed the visualisation of metachromatic mast cells. The comparative study showed that tryptase positive cells were more numerous than metachromatic cells in all layers of the studied organ but the density of ghrelin positive cells was the highest. Tryptase immunohistochemistry allowed distinguishing ghrelin expressing mast cells from all ghrelin positive cells. The highest number of ghrelin positive cells indicated that not only mast cells but other cells also express ghrelin. The results allowed concluding that studied mast cell types had different density in the three main layers of common hepatic duct. The highest density of mast cells in the muscular layer and the possibility of mast cells to express ghrelin define its role in regulation of common hepatic duct motility and glandular secretion. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Mast cells present in the connective tissue stroma release pro inflammatory and mitogenic cytokines. The mast cell in tumor act as a host immunologic anti tumor response. More than 90% of oral cancers are squamous cell carcinomas with oral epithelial dysplasia being the most common potentially malignant disorder. Mast cells play an important role in tumourigenesis. In some studies, with different granules of mast cell is closely related with angiogenesis and tumor invasion. In this study we used toluidine blue for the staining because it reveals mast cells as large, purple, oval and granulated cells. MATERIAL AND METHODS: 30 cases of oral epithelial dysplasia, 30 cases of Oral squamous cell carcinoma (OSCC) and 10 cases of Normal oral mucosa (NOM) were studied for mast cell number using toluidine blue. Mast cells were counted using an Olympus CX41 microscope fitted with an Olympus oculometer grid. Counting was carried out at ×40 by two independent observers and was done in six non overlapping fields in each slide. Mast cells were identified on the basis of the purple color attained by the granules after toluidine blue staining, but the nucleus of these cells appeared blue. RESULTS: Highly significant increase of mast cells in oral epithelial dysplasia on comparison with OSCC whereas there was only a significant increase in mast cells in OSCC on comparison with NOM. CONCLUSION: Mast cells can be used an indicator of increased angiogenesis and can help in the prediction of carcinogenesis, its progression, and also in the prognosis of the malignant lesions. [ABSTRACT FROM AUTHOR]

Due to the similar pattern of ghrelin localisation in human and porcine intestine, swine are described as a suitable animal model for experiments related to ghrelin and its receptors. In a previous study of ours, the presence of ghrelin immunoreactive endocrine cells in common bile duct (Ductus choledochus) (CBD) of domestic swine was established. However, data regarding the distribution of mast cell types in the CBD in this species are missing. The current study aimed to determine the distribution of tryptase-, ghrelin- and toluidine blue positive mast cells in the wall of extra- and intramural parts of porcine CBD. For this purpose, immunohistochemical staining for detection of tryptase was performed in order to identify ghrelin reactivity in mast cells. Additionally, toluidine blue staining was carried out to compare the number of metachromatic mast cells with that of tryptase positive cells. The comparative quantitative analysis showed that the number of tryptase immunorective cells was higher than that of metachromatic ones in the CBD wall. Ghrelin immunoreactive cells were the most numerous, therefore it can be assumed that not only mast cells but other cells also contain ghrelin. The three mast cells types were more abundant in the propria and subserosa of the intramural part than in the same layers of extramural CBD part. In the muscle layer, mast cell number was higher in the extramural than in the intramural part of the duct. In conclusion, taking into account the results obtained, an important role of mast cells play in controlling CBD motility and biliary gland function was suggested. [ABSTRACT FROM AUTHOR]

Introduction: Sepsis-associated encephalopathy (SAE) is a diffuse cerebral dysfunction resulting from a systemic inflammatory response to infection; however, its pathophysiology remains unclear. Sepsis-induced neuroinflammation and blood-brain barrier (BBB) disruption are crucial factors in brain function disturbance in SAE. Mast cells (MCs) activation plays an important role in several neuroinflammation models; however, its role in SAE has not been comprehensively investigated. Methods: We first established a SAE model by cecal ligation puncture (CLP) surgery and checked the activation of MCs. MCs activation was checked using immumohistochemical staining and Toluidine Blue staining. We administrated cromolyn (10mg/ml), a MC stabilizer, to rescue the septic mice. Brain cytokines levels were measured using biochemical assays. BBB disruption was assessed by measuring levels of key tight-junction (TJ) proteins. Cognitive function of mice was analyzed by Y maze and open field test. Transwell cultures of brain microvascular endothelial cells (BMVECs) co-cultured with MCs were used to assess the interaction of BMVECs and MCs. Results: Results showed that MCs were overactivated in the hippocampus of CLPinduced SAE mice. Cromolyn intracerebroventricular (i.c.v) injection substantially inhibited the MCs activation and neuroinflammation responses, ameliorated BBB impairment, improved the survival rate and alleviated cognitive dysfunction in septic mice. In vitro experiments, we revealed that MCs activation increased the sensitivity of BMVECs against to lipopolysaccharide (LPS) challenge. Furthermore, we found that the histamine/histamine 1 receptor (H1R) mediated the interaction between MCs and BMVECs, and amplifies the LPS-induced inflammatory responses in BMVECs by modulating the TLR2/4-MAPK signaling pathway. Conclusions: MCs activation could mediate BBB impairment and cognitive dysfunction in septic mice in a histamine-dependent pathway. [ABSTRACT FROM AUTHOR]

Background. Atopic dermatitis is a common dermatological disease, and mast cell degranulation is believed to be related with the progression of atopic dermatitis. Mas-related G protein-coupled receptor-X2 (MRGPRX2), and calcium release-activated calcium channel protein 1-2 (ORAI-1, ORAI-2) are involved in mast cell degranulation. Celastrol is an active monomer of Tripterygium wilfordii, and it presents an antiatopic role. Methods. 2,4-Dinitrofluorobenzene (DNFB) and compound 48/80 (C 48/80) were used to establish a slow and acute scratching animal model, respectively. Hematoxylin-eosin and toluidine blue staining was used to investigate tissue injury. Inflammatory factor concentration was measured with ELISA. The expression of MRGPRX2, ORAI-1, and ORAI-2 was detected with immunohistochemistry (IHC) staining. Gene expression profiling and microRNA array were performed to investigate gene differential expression. Results. Celastrol greatly inhibited atopic dermatitis-related tissues injury, mast cell production, histamine release, scratching level, inflammatory factor expression, and activation of MRGPRX2/ORAI axis in the DNFB-induced atopic dermatitis model. The influence of Celastrol on atopic dermatitis was remarkably reversed by overexpression of MRGPRX2. Conclusion. We found that the improvements of atopic dermatitis caused by Celastrol were reversed by treatment with MRGPRX2OE, indicating that Celastrol might affect atopic dermatitis through MRGPRX2. This study might provide a novel thought for the prevention and treatment of atopic dermatitis by regulating MRGPRX2. [ABSTRACT FROM AUTHOR]

Research background. Despite clearly recognized links between increased body mass and increased risk for various pathological conditions, therapeutic options to treat obesity are still very limited. The aim of the present study is to explore the effect of low-molecular-mass collagen fragments obtained from the scales of Antarctic wild marine fish on rats' visceral and subcutaneous white adipose tissue in a high-calorie diet-induced obesity model. Experimental approach. The study was conducted on outbred rats, which were divided into 3 experimental groups: (i) control, consuming standard food (3.81 kcal/g), (ii) obese group, consuming a high-calorie diet (5.35 kcal/g), and (iii) obese group, consuming a high-calorie diet (5.35 kcal/g) with intragastric administration of low-molecular-mass collagen fragments (at a dose 1 g/kg of body mass during 6 weeks). Low-molecular-mass collagen fragments were obtained by a procedure that included collagen extraction from fish scales and enzymatic hydrolysis with pepsin. Apart from hematoxylin and eosin staining, fibrosis level was assessed by histochemical Van Gieson's trichrome picrofuchsin staining, and mast cells were analysed by toluidine blue O staining. Results and conclusions. Group treated with low-molecular-mass fragments of collagen exhibited decreased rate of mass gain, relative mass, area occupied by collagen fibre of both visceral and subcutaneous adipose tissue, and cross-sectional area of both visceral and subcutaneous adipocytes. Treatment with low-molecular-mass fragments of collagen reduced the infiltration of immune cells, number of mast cells and their redistribution back to the septa. This was also accompanied by a decreased number of the crown-like structures formed by the immune cells, which are markers of chronic inflammation that accompanies obesity. Novelty and scientific contribution. This is the first study that reports the anti-obesity effect of low-molecular-mass fragments produced as a result of controlled hydrolysis of collagen from the scales of Antarctic wild marine fish in the in vivo model. Another novelty of this work is the observation that the tested collagen fragments not only reduce the body mass, but also improve the morphological and inflammatory parameters (decrease in the number of crown-like structures, immune cell infiltration, fibrosis and mast cells). Altogether, our work suggests that low-molecular-mass collagen fragments are a promising candidate for amelioration of some comorbidities linked to obesity. [ABSTRACT FROM AUTHOR]

The relevance of the work is related to the need to develop methods for determining individual opportunities to minimize the harmful effects of ionizing radiation. Experiments were conducted to search for informative indicators of the structure of mast cells to predict the individual effectiveness of the radioprotective effect of hypoxia. A study was performed on white male rats. In 81 animals, before the main experiment, a hypoxic sample was carried out once, by placing the rats in a gas mixture containing 8% oxygen and 92% nitrogen (GGS-8). In each of these rats, a biopsy of the skin of the auricle was performed immediately before the test and at the time of its completion. In the biopsies, the content of various forms of mast cells detected by the method of metachromasia with toluidine blue was determined. After a week, all animals of the main group (81 rats) were exposed to total γ-irradiation at a dose of 11 Gy under the protection of GGS-8. Rats in the control group (63 rats) were irradiated in the same dose in the air. The life expectancy after the exposure was assessed. The radioprotective effect of the gas hypoxic mixture was confirmed, which is expressed in an increase in the average life expectancy of irradiated rats by 2.2 times. A weak relationship between individual quantitative characteristics of mast cells and the life expectancy of irradiated animals is shown. A formal expression of the equation of regression of the number of mast cells on the life expectancy of animals irradiated under the protection of hypoxia has been created. On the basis of regression analysis, groups of animals in which the highest radioprotective effect of hypoxia was manifested were revealed. The minimum life expectancy after irradiation is characteristic of rats with extreme values of the mast cell reactivity index, and all surviving cases are noted in rats with average values of the indicator. Among them there was not a single animal with an intestinal form of death. This indicates the possibility of predicting the radioprotective effect of hypoxia based on an assessment of the functional activity of mast cells. [ABSTRACT FROM AUTHOR]

We aimed to investigate the relationship between the degree of mast cells' (MCs) infiltration and clinicopathological features of prostate cancer (PCa) malignancy and to find out the possible mechanisms of the involvement of these cells in the formation of the aggressive course of the PCa development. The study was conducted on the clinical material of 60 patients with PCa of stages II-III. MCs in the PCa tissue were determined by a histochemical method using toluidine blue. The expression of osteopontin (OPN) was studied by the immunohistochemical method. The expression of miRNA-21, -126, -146a, -181a, and -221 was investigated by quantitative real-time PCR. Statistical processing of the results was performed using the GraphPad Prism 8 program. Our results demonstrated that the increased level of infiltration and degranulation of MCs in the PCa tissue was associated with such indices of the malignancy of the tumor process as the Gleason score and the preoperative PSA level in the blood serum of patients. A high level of MCs infiltration of the PCa tissue was associated with a significant decrease in the two-year recurrence-free survival rates of the patients by 23.3% (p=0.0455). A high degree of MCs infiltration of the PCa tissue was associated with 1.2 times (p=0.0347) higher level of OPN expression and 1.7 (p=0.0051) and 1.65 (p=0.0087) times lower levels of miR-126 and miR-181a expression, respectively. The obtained results indicate the participation of MCs as a factor of the tumor microenvironment in the PCa progression. [ABSTRACT FROM AUTHOR]

Background: Senecio scandens Buch.-Ham (S. scandens) belongs to the Compositae family. As a Traditional Chinese medicine, S. scandens has been used in China to treat conjunctivitis, mastitis and vaginitis, it also has the function of antibacterial and relieving itching. Methods: Water extract of S. scandens (WSS) was prepared and its quality was controlled by HPLC. The antipruritic effects of WSS were evaluated by itch behavioral experiments. The oxazolone and compound 48/80 were induced to mice scratch behavior, scratch was recorded 30 min after sensitization. The relationship between the antipruritic mechanism and MrgprB2 on mast cell was studied by using mast cell-deficient Kit (W-sh) "Sash" mice and MrgprB2−/− mice. The mast cells were observed by toluidine blue staining. In vitro, the effects of WSS on MrgprB2 were studied by calcium imaging; The whole-cell patch clamp method recorded the MrgprB2 mediate voltage-dependent currents in mast cells. Results: The content of rutin (0.012%) and hyperin (0.014%) in the WSS were determined. WSS could ameliorate the pruritus induced by Oxazolone (inhibition was 41.19%, p = 0.004) and compound 48/80 (inhibition was 50.29%, p = 0.001). Meanwhile, WSS could reduce the number of mast cells in mice skin tissue with allergic contact dermatitis (ACD) (p = 0.002) or compound 48/80 (p = 0.013). In addition, WSS could inhibit the calcium influx (1 mg/mL: p = 0.001, 3 mg/mL: p < 0.0001) and the voltage-dependent currents induced by activation of MrgprB2 on mast cell. WSS also attenuated the calcium influx induced by compound 48/80 in HEK293 cells overexpressing MrgprB2/X2. Conclusion: These results showed that WSS could ameliorate pruritus by inhibiting MrgprB2 receptor on mast cells. Graphical [ABSTRACT FROM AUTHOR]

Background: Mast cells (MCs) are immune cells of the myeloid lineage and are present in connective tissues throughout the body. Mastocytosis regulates many physiologic processes and affects the pathogenesis of allergic conditions, anaphylactic reactions, autoimmune disorders and leukemias. Toluidine blue is commonly employed as a special stain for MCs that uniformly imparts blue color to both immature and mature cells. Csaba stain that distinguishes mature from immature MCs has not been widely explored. However, its use in differentiating mature and immature cells has not been reported in the literature. The identification of mature and immature MCs may provide a major clue for the diagnosis of any unrecognized systemic pathologies. Objectives: To evaluate the staining efficacy of Csaba stain, toluidine blue and Leishman's stains in the identification of MCs To compare the effectiveness of Csaba stain, toluidine blue and Leishman's stains to identify MCs in inflammatory pathologic lesions. Materials and Methods: Fifty sections of inflammatory lesions were subjected to Csaba stain, toluidine blue and Leishman's stains each for studying MCs. The staining efficacy of the three stains was compared for parameters such as homogeneity, specificity, staining intensity, granular staining property and differentiation between mature and immature cells. Results: The Csaba, toluidine blue and Leishman's stains showed statistically insignificant P = 0.50, 0.95, 0.29, 0.48 for homogeneity, specificity, staining intensity and granular staining property respectively, but Csaba stain showed statistically significant P = 0.0001* in differentiating mature from immature cells. Conclusion: Csaba stain is more effective in differentiating mature from immature MCs compared to the other special stains. [ABSTRACT FROM AUTHOR]

Background: Prolonged exposure to general anesthesia (GA) results in long-lasting cognitive impairment, especially during critical stages of brain development. An exaggerated neuroinflammation induced by anesthesia is generally considered to be a key cause of cognitive impairment. Materials and methods: Postnatal day 7 (PND 7) mice were exposed to GA by isoflurane inhalation for 6 h or mock anesthesia. Disodium cromoglycate (DSCG) was intraperitoneally injected daily for 2 weeks, beginning from 30 min before anesthesia. The post-anesthesia evaluation included behavioral tests, toluidine blue staining, immunofluorescence and western blot. Results: Our results demonstrated the long-term cognition were impaired after 6 h GA exposure in neonatal mice. DSCG treatment ameliorated early mast cells (MCs) degranulation and mast cell tryptase (MCT) expression, which helps to attenuate subsequent neuroinflammation, activation of microglia and astrocytes, and damage to oligodendrocytes and synapses to improve cognitive impairment. Conclusion: Disodium cromoglycate could effectively improve long-term cognitive impairment after GA exposure in neonatal mice. [ABSTRACT FROM AUTHOR]

A 14‐year‐old, female, spayed warren hound presented with an acute history of collapse, pale mucous membranes and abdominal distension. Abdominal ultrasound and abdominocentesis revealed a haemoabdomen secondary to a ruptured splenic mass. The dog underwent an emergency splenectomy and splenic histopathology, including toluidine blue staining, was consistent with a mast cell tumour. The dog was diagnosed with a primary splenic mast cell tumour based on the absence of a primary mast cell tumour in another location at the time of presentation or in a review of the dog's medical record. Following surgery, staging identified hepatic infiltration, and adjuvant chemotherapy with vinblastine and prednisolone was started. The dog was euthanased 97 days after surgery due to progressive disease and recurrence of the haemoabdomen. Visceral mast cell tumours should be considered as an uncommon differential diagnosis in dogs presenting with haemoabdomen due to a ruptured splenic mass. [ABSTRACT FROM AUTHOR]

Introduction: The interaction of cancer cells and the host within the tumour microenvironment plays a major role in determining the outcome of cancers. Mast cells are part of the innate immune system that interact with tumour cells and known to have pro-tumourigenic and antitumourigenic action through their mediators. Their role in the outcome of invasive breast cancer is still not clear with studies showing both a beneficial role as well as a role in tumour progression. Aim: To assess Mast Cell Density (MCD) in tissues of invasive carcinoma of breast and compare with clinicopathological parameters to infer their biological significance. Materials and Methods: The study was a retrospective cross-sectional study carried out at the Department of Pathology, SRM Medical College Hospital & Research Centre, SRMIST, Kattankulathur, Chennai, India on 51 cases of invasive carcinoma of breast received between January 2011 and July 2013 and the study conducted between August to November 2013. Clinical parameters and histopathological findings were recorded. Mast cells were clearly demonstrated in tissue using Toluidine Blue stain at pH 2.3. The MCD within primary malignant breast tumour tissue (mastectomy specimens, n=51) was assessed using an eyepiece grid and expressed as no. of cells/per sq. mm. Statistical analysis of all parameters was performed using SPSS software (v 17.0) to analyse association of MCD with clinicopathological parameters. Results: The MCD was significantly higher in malignant breast tissue compared to non neoplastic breast tissue (p<0.0001). No significant difference in MCD was observed between tumour size groups (T1, T2, and T3) (p=0.6967). No statistically significant difference in MCD was observed between the four histological types observed (p=0.892). The majority of the tumours were of Grade 2 category (n=37), followed by Grade 3 (n=11) and Grade 1 (n=3). No significant difference in MCD was observed between the three histological grades (p=0.785). The MCD was significantly higher in patients without lymph node metastasis compared to the group with lymph node metastasis (p=0.0023*). The MCD in invasive carcinoma of breast, post-chemotherapy group was significantly higher than that in invasive carcinoma of breast pre-chemotherapy group (p=0.0064). Conclusion: The current study shows significantly increased MCD at the periphery of the carcinoma breast tissue in patients without lymph node metastasis compared to those with lymph node metastasis. Hence, a potential antitumourigenic and beneficial role of mast cells in invasive primary breast carcinoma could be inferred and may serve as one of the prognostic indicators for patient stratification for various treatment options including immunotherapy. [ABSTRACT FROM AUTHOR]

Tricin, a flavone belonging to the Gramineae family, has been confirmed to be the primary compound in a Zizania latifolia extract (ZLE) that prevents allergies. Various allergic reactions occur because of the unbalanced differentiation of T help cells (Th) and the consequent overproduction of IgE. Therefore, the regulation of Th1 and Th2 responses by T helper cell differentiation is essential for suppressing allergic responses. This study confirmed the immunomodulatory effects of ZLE and the major compound tricin in an OVA-sensitized mouse model. The IgE and OVA-specific production of tricin and ZLE in plasma were investigated in OVA-sensitized mice. The effects of tricin and ZLE on the amount of Th1 and Th2 cytokines and transcription factors released in splenocytes were investigated in OVA-sensitized mice. The skin roughness and the number of mast cells were confirmed by staining the skin surface with H&E and toluidine blue. Tricin and ZLE reduced the plasma IgE and OVA-specific-IgE levels significantly compared to the OVA group. On the other hand, tricin and ZLE promoted the release of the Th1 cytokines IL-12 and IFN-γ and inhibited the release of Th2 cytokines (IL-4, -10, -13, and -5) in OVA-sensitized mice. Tricin and ZLE induced T-bet and NFATc2 expression, and-down regulated GATA-3 levels. The skin roughness and the number of mast cells decreased in the OVA-immunized mice. Overall, the data indicate that tricin and ZLE may prevent allergy-related diseases through immunomodulation. [ABSTRACT FROM AUTHOR]

Copyright of Türkiye Klinikleri Journal of Veterinary Sciences is the property of Turkiye Klinikleri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pseudoallergic reactions are hypersensitivity reactions mediated by an IgE-independent mechanism. Since allantoin (AT)-mediated pseudoallergy has not been studied, in this study, our objective is to investigate the anti-pseudoallergy effect of AT and its underlying mechanism. In vitro, β-hexosaminidase (β-Hex) and histamine (HIS) release assays, inflammatory cytokine assays, toluidine blue staining, and F-actin microfilament staining were used to evaluate the inhibitory effect of AT in RBL-2H3 cells stimulated with Compound 48/80 (C48/80). Western blot analysis is further performed to investigate intracellular calcium fluctuation-related signaling pathways. In vivo, Evans Blue extraction, paw swelling, and the diameter of Evans Blue extravasation were evaluated, and skin tissues are examined for histopathological examination in mice with passive cutaneous anaphylaxis (PCA) induced by C48/80. Body temperature is measured, and the levels of cytokines are further determined by ELISA kits in mice with active systemic anaphylaxis (ASA) induced by C48/80. The results show that AT dose-dependently inhibited degranulation in C48/80-stimulated RBL-2H3 cells by inhibiting β-Hex and HIS release, reducing the levels of TNF-α, IL-8, and MCP-1, inhibiting shape changes due to degranulation and disassembling the F-actin cytoskeleton. Furthermore, AT dose-dependently inhibits the phosphorylation of PLCγ and IP3R. In vivo, AT decreased Evans Blue extravasation, paw swelling, and the diameter of Evans Blue extravasation and significantly ameliorate pathological changes and mast cell degranulation in C48/80-induced PCA. Furthermore, AT help the mice recover from the C48/80-induced decrease in body temperature and decreased the levels of cytokines in C48/80-treated ASA mice. Our results indicate that allantoin inhibits compound 48/80-induced pseudoallergic reactions. AT has the potential to be used in IgE-independent anti-allergic and anti-inflammatory therapies. [ABSTRACT FROM AUTHOR]

Mast cells in the brain are associated with increased inflammation during the acute period following exposure to infection; these cells are important for destroying the infectious agents. We investigated the relation between histopathological lesions and mast cells in sheep brains infected with Listeria. Pons and medulla regions from 17 infected and eight normal sheep brains were examined. Microabscesses and perivascular infiltration were assessed for histopathology. Mast cells were identified using toluidine blue and Listeria monocytogenes were investigated immunohistochemically. We found a significant increase in mast cells in infected sheep brains that was related directly to the extent of brain lesions. A strong correlation was found between mast cells and microabscess formation. A correlation between bacteria level and brain lesions also was observed, but not between bacteria level and mast cells. Our findings indicate that mast cells are increased following Listeria infection in sheep in proportion to the severity of brain lesions; the increase may contribute to acute inflammatory reactions and also may destroy bacteria directly. [ABSTRACT FROM AUTHOR]

Background:Mast cells are well-known to be involved in allergic, inflammatory, and immune reactions. In addition, they are also involved in pain, tissue damage as well as repair. The present study was conducted to assess the role of mast cells and angiogenesis in oral squamous cell carcinoma. Materials & Methods:62 formalin-fixed oral biopsies of oral squamous cell carcinoma (OSCC) and 10 normal oral mucosa biopsies were also enrolled. Micro-vessels were stained with cluster of differentiation (CD)-34 and mast cells were counted using the Toluidine blue stain. Results: Site involved was buccal mucosa in 22, lower lip in 4, palate in 1, tongue in 6, gingiva in 5, alveolus in 10 and floor of mouth in 14 cases. The difference was significant (P< 0.05). The mean mast cell density in OSCC was 10.2/ HPF and in normal mucosa was 1.5/ HPF. The mean micro vessel density in OSCC was 24.8/ HPF and in normal mucosa was 10.3/ HPF. The difference was significant (P< 0.05). Conclusion: Angiogenesis does increase in oral squamous cell carcinoma and mast cells also invade the peri-tumor tissue, but they are not directly correlated. [ABSTRACT FROM AUTHOR]

Mast cells, known as pro‐inflammatory effector cells, are immunocytes present in the meninges and may be involved in the pathophysiology of migraine. This study aims to evaluate the histomorphometric parameters of mast cells located in the convexity of the human intracranial dura mater. For this, samples of intracranial dura mater from eight human fresh cadavers were collected between 8‐ and 24‐h post‐mortem. The whole samples were fixed and, subsequently, two fragments of 1.5 cm² each were cut from four different areas of the dura mater convexity, containing a segment of the middle meningeal artery, totaling 64 fragments. After histological processing, the fragments were submitted to microtomy (5 and 10 µm), stained with toluidine blue (0.1%), or immunohistochemically labeled for tryptase, and analyzed using optical microscopy. The following histomorphometric parameters were evaluated: distance from mast cells to vessels, the density of mast cells, and percentage of mast cells with degranulation. Histomorphometric analyzes showed a higher density of mast cells in the vicinity of blood vessels (arterial and venous), with distances around 0–150 µm. A greater number of mast cells was detected near venous vessels in the periosteal layer (17.0 ± 10.1 cells/mm²) than in the meningeal layer (14.1 ± 7.0 cells/mm²) (p < 0.05). Mast cells from the region close to the superior sagittal sinus were found in greater quantity close to the venous vessels (16.7 ± 10.1 cells/mm²) than to the arterial vessels (11.2 ± 7.5 cells/mm²) (p < 0.05). In short, in the convexity of the human intracranial dura mater, mast cells are located close to blood vessels, with a greater number of cells next to the venous vessels of the periosteal layer and in the proximal region of the superior sagittal sinus. [ABSTRACT FROM AUTHOR]

Objectives: The ethyl acetate extraction of Artemisia ordosica Krasch (AOK) root showed anti-allergic rhinitis (AR) effect, while the active compounds and pharmacological targets were unknown. Methods: The P815 degranulation was established by cell counting kit 8 assay, β-hexosaminidase releasing assay and toluidine blue staining. The flavonoids were screened in vitro. Then toluidine blue staining and ELISA were carried out to investigate the anti-inflammatory effects of the active compound. Network pharmacology was implemented to explain the mechanisms of the active compound. iGEMDOCK was used to investigate the binding between active compound and hub targets. Key findings: C48/80 was the optimum reagent in triggering P815 degranulation. Naringenin could significantly decrease P815 degranulation. Meanwhile, naringenin could remarkably increase the IL-4 and decrease the tumour necrosis factor-α. The effect of naringenin on AR was achieved by regulating multiple targets (e.g. AKT1, MAPK3, VEGFA) and pathways (e.g. pathways in cancer, VEGF signalling pathway). Nine hub proteins were obtained by topological analysis. Multiple hydrogen bonds and van der Waals forces were formed between the naringenin and the residues of hub proteins. Conclusions: Naringenin might be one of the effective ingredients of AOK against AR. And its effects could achieve through regulating multiple targets and pathways. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to investigate the presence of synovial mast cells (MCs) in hip and knee tissue from osteoarthritis (OA) patients and to correlate them with clinical and radiological data. Methods: Synovial tissue was obtained during arthroplasty from 60 patients, 30 with knee OA and 30 with hip OA. Control synovial tissue was obtained from 30 patients without OA, 15 undergoing above-knee amputation and 15 receiving a hip replacement for fracture. Before surgery, the radiographic findings were graded according to the Kellgren-Lawrence system and clinical data including pain (VAS) and functional information (KOOS and HOOS) was collected. The tissue was stained with hematoxylin–eosin and toluidine blue for histochemistry and incubated with CD117 and CD31 antibodies for immunohistochemistry. MC and vessel number and synovitis score were determined in all samples. Results: Mean MC number, synovitis score and vessel number were significantly higher in the OA samples (p < 0.05) than in control tissue. MC number correlated with the synovitis score and disease severity in both patient groups. Conclusions: The prevalence of MCs in synovium from OA patients and their association with synovial inflammation and pain suggest a role for them in OA pathophysiology. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Isfahan Dental School is the property of Isfahan University of Medical Sciences & Health Services, School of Dentistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mast cells are immune cells of myeloid lineage, characterized by the presence of cytoplasmic granules. These cells play a significant role in multiple pathologies, such as urticaria and type 1 hypersensitivity reactions. Mast cells in tissue sections can be demonstrated with metachromatic stains, such as toluidine blue. Metachromatic staining of mast cells is influenced by the type of mast cell, pH of the staining solution and fixative employed. The objective of this study is to identify a simple, consistent, and reproducible toluidine blue staining method to quantify the mast cells in whole slide skin images using automated image analysis. Skin sections from naive mice and atopic dermatitis mice were stained with toluidine blue methods by Churukian-Schenk and Luna. Luna's toluidine blue staining method without the eosin counterstaining provided optimal staining of mast cells with a greater contrast to the background. The Churukian-Schenk toluidine blue method resulted in slight background staining which confounded the accurate detection and quantification of mast cells in mouse skin sections using an automated image analysis algorithm. Using the Luna toluidine blue stain, a 5-fold increase in the total number of mast cells was observed in atopic dermatitis skin samples as compared to naive mice. In summary, a simple, conventional, and reproducible toluidine blue method was identified to quantify the mast cells in mouse skin sections using an automated image analysis algorithm. [ABSTRACT FROM AUTHOR]

The mast cell mediators and distribution of lung mast cells in rats are often discussed in experimental studies on pulmonary fibrotic and allergic processes associated with changes in numbers of these cells, but information on the normal distribution of metachromatic and tryptase-positive mast cells in the interalveolar septa is scarce. There are no data on the presence of ghrelin in lung mast cells as well as the age-specific features of localisation and the number of mast cells in the interalveolar septa in rats of different ages. Therefore, the purpose of the present study was to determine the distribution of metachromatic, tryptase-, and ghrelin-positive mast cells in the interalveolar septa in 20 day-, 3 month- and 1 year-old rats. Tissue sections stained with toluidine blue had been taken from the left lung to visualise metachromasia and immunohistochemical expression of tryptase and ghrelin. The results showed that the amount of metachromatic mast cells in the interalveolar septa was significantly lower than that of tryptase- and ghrelin-positive cells. This allowed suggesting that mast cells were permanent occupants of the rat lung parenchyma and, on the other hand, the expression of ghrelin in their granules was most likely related to the synthesis of this protein. Our study showed that immunohistochemical identification by tryptase expression was more accurate than toluidine blue staining. [ABSTRACT FROM AUTHOR]

Introduction: We previously reported that the intravitreal activities of chymase and tryptase were more increased in the patients with macular hole (MH) and epiretinal membrane (ERM) than in those with proliferative diabetic retinopathy (PDR) and that the source of these serine proteases might be mast cells in the bursa premacularis (BPM). The purpose of this study was to compare the density of mast cells in BPM samples obtained from MH, ERM, and PDR patients. Methods: BPM and vitreous core samples were first collected during vitrectomy from eyes afflicted with vitreoretinal diseases (MH: 6 eyes, ERM: 3 eyes, and PDR: 9 eyes), and then were stained with hematoxylin, toluidine blue, antibodies against chymase and tryptase, and a terminal deoxynucleotidyl transferase dUTP nick end labeling assay kit. Results: Hematoxylin nuclear staining showed fewer positive-staining cells in the BPM samples obtained from PDR patients than in those obtained from MH and ERM patients. Toluidine blue staining of the BPM revealed metachromasia in the mast cells of the patients with MH and ERM, but not those of the patients with PDR. In addition, immunostaining using anti-chymase and anti-tryptase antibodies showed that the BPM samples were more intensely stained than the vitreous core samples from the patients with MH and ERM and that both tissue samples were poorly stained in the patients with PDR. The apoptotic cells were more frequently observed in the BPM samples from patients with MH than in those from patients with PDR. Conclusions: These findings indicated that lower activities of chymase and tryptase in the vitreous of PDR patients appeared to be attributable to the decreased presence of mast cells in the BPM. The lack of mast cells in the BPM might be related to the pathogenesis of PDR. [ABSTRACT FROM AUTHOR]

Background: Periapical granuloma and periapical cysts develop as a sequela of inflammation of dental pulp, usually a consequence of an infected root canal. Mast cells (MCs) have most frequently been implicated in the pathophysiology of periapical lesions such as periapical granulomas and cysts. Aims: The present study was undertaken to emphasize the presence and quantification of MCs in periapical lesions (granulomas and cysts) using toluidine blue stain, with an aim to elucidate their role in the pathogenesis of these lesions. Materials and Methods: The study comprised a total of 55 previously diagnosed cases (30 cases of radicular cyst and 25 cases of periapical granuloma) selected from the departmental archives. The MCs were quantified in all the sections in the three zones, namely the epithelial, subepithelial, and deeper connective tissue zones. The results were sent for statistical analysis. Statistical Analysis: Wilcoxon paired t-test and Mann–Whitney U test were applied for intra- and intergroup comparison MCs in different zones of periapical granulomas and radicular cyst, respectively. Results: A statistically significant difference was observed between the two lesions in all the three zones, i.e., epithelial, subepithelial, and in deeper connective tissue zone with P = 0.001. Conclusion: Although MCs were present in all the three zones of both periapical cysts and granuloma, they were predominantly observed in radicular cysts than in periapical granuloma. This suggests a significant role of MC in initiation, development, and progression of these periapical lesions. [ABSTRACT FROM AUTHOR]

Background. Oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs) are epithelial-derived pathologies which share inflammation as a common initial pathogenic-inducing state. Mast cell is a key immune modulating cell which is primarily involved in initiation and propagation of inflammation. The role of mast cell in OPMDs and OSCC has been an established fact; however, its definitive pathogenic correlation is still under study. The objective of the study was to evaluate the number of mast cell in OPMDs and OSCC using special stain correlating its probable role as a promoter or retarder of OSCC. Materials and Methods. Forty-five archival histopathologically confirmed cases each of OPMD and OSCC were studied for mast cells using toluidine blue and Alcian blue-safranin stain and compared with 10 normal oral mucosal tissues. Comparisons between the mast cells count was also performed between the two special stains. Results. Among 100 cases, 67% were males and 33% were females. The mean age was 41.68 ± 13.39; 55.06 ± 12.55; and 18.4 ± 2.54 years for OPMDs, OSCC, and normal, respectively. A statistically significant increase in mast cells among OPMDs (9.88 ± 7.9) and OSCC (6.711 ± 3.94) was observed compared to normal oral mucosa. The mast cell count reduced among OSCC in comparison to OPMDs which was significant as well. The mean mast cell count for Alcian blue-safranin stain was higher than toluidine blue stain. Conclusion. There is a decrease in mean mast cell count from OPMDs to OSCC which is suggestive of protective role of mast cell. Proper quantification of mast cells using specific stains can guide to define prognosis in oral potentially malignant disorders and oral cancer. [ABSTRACT FROM AUTHOR]

Introduction and hypothesis: As a notable chronic disorder, the incidence of interstitial cystitis (IC) has been documented to have increased among the female population with activity in microRNA-495 (miR-495) implicated in this disease. The current study was aimed at elucidating the effects associated with miR-495 on the inflammatory response and bladder fibrosis in rats with ulcerative IC via the JAK–STAT pathway by targeting JAK3. Methods: Ulcerative IC rat models were established. The targeting relationship between JAK3 and miR-495 was evaluated using luciferase reporter assay. After gain- or loss-of-function assays, mast-cell infiltration was assessed using toluidine blue staining, bladder fibrosis using Masson staining, and NO content using nitrate reductase method. JAK3 protein expression was detected by immunohistochemistry, JAK3, STAT1, STAT3, TGFβ-1, Col-I, Col-III, JAK1, JAK2, p-STAT1, and p-STAT3 expression by RT-qPCR and Western blot analysis, and serum IL-6, IL-8, IL-10, IL-17, and TNF-α levels in rats by ELISA. Results: Following transfection of overexpressed miR-495 or siRNA-JAK3, a diminished degree of mast-cell infiltration, number of mast cells, bladder fibrosis, NO content, JAK3-positive expression, mRNA expression of JAK3, STAT1, STAT3, TGFβ-1, Col-I, Col-III, protein expression of JAK1, JAK2, JAK3, p-STAT1, p-STAT3, and expression of IL-6, IL-8, IL-10, IL-17, and TNF-α were identified. Conclusions: Collectively, our key findings provide evidence supporting the notion that the overexpression of miR-495 ameliorates inflammatory response and bladder fibrosis in ulcerative IC rat models via inactivation of the JAK–STAT signaling pathway by inhibiting JAK3. [ABSTRACT FROM AUTHOR]

Background: Perfumes, whether original or fake, are considered of great economic value. However, overzealous use of perfumes could be associated with local or systemic side effects. Aim: This study was conducted to investigate the effects of daily use of original and fake perfumes on numbers and distribution of mast cells in several organs and tissues of Wistar rats. Methods: Three different kinds of original perfumes coded as O1, O2, and O3 and their fake counterparts coded as F1, F2, and F3 were applied once daily directly on the skin of rats for 28 consecutive days. At the end of the study, representative tissue samples were taken and processed for histopathological examination using Hematoxylin and Eosin, toluidine blue, and Wright's stains. Results: A significant (p < 0.05) elevation in mast cell count was observed in F3, O3, F1, and F2 compared to the control group. The majority of mast cells were distributed in the hepatic perivascular tissues, peribronchial and pleural tissues. There was a significant (p < 0.05) elevation in mast cell count in along the interalveolar wall, peribronchial area, and pleura tissues in F1 and O3 groups. Conclusion: Results of this study indicated that repeated use of both original and fake perfumes was associated with an increased number of mast cells in different body organs and tissues. [ABSTRACT FROM AUTHOR]

In the present study, toluidine blue for metachromasia and berberine sulfate for heparin fluorescence were used to determine the localisation and distribution of mast cells as well as the percent of hepa-rin-positive cells (MCH) in normal lumbar spinal ganglia (dorsal root ganglia) of domestic swine. Mast cells density was established after estimating the number of these cells per ganglion. Mast cells with metachromasia (MCTB) were observed predominantly in the ganglion capsule near the blood vessels. The number of mast cells inside the ganglia (2.10±1.45 in males and 2.20±1.03 in females) was significantly lower than in the capsule (13.30±1.95 in males and 13.60±2.42 in females) in both genders (P

Introduction. Oral ulcers are one of the most frequent diseases in the oral cavity. Wound healing is a complicated process including inflammation, proliferation, epithelialization, angiogenesis and collagen matrix formation. The aim of this study was to evaluate the effect of oleuropein upon oral wound healing in healthy and diabetic mice by counting mast cells using toluidine blue staining. Materials and methods. The experimental study was performed on 96 mice divided into 6 groups: the control, the group receiving oleuropein extract, those receiving base material, diabetic control, diabetic receiving oleuropein, and the diabetic group receiving the base substance. 2 mm ulcers were made on the palate of mice and the animals were sacrified on the 2nd, 4th, 6th and 8th day. Blocks prepared from the wound area were stained using standard toluidine blue, and a number of granulated and degranulated mast cells was studied under the optical microscope. Data was entered into a checklist and analyzed using statistical software SPSS 21, ANOVA and Post hoc Tukey tests, at a significant level of 0.05. Results and discussion. In this study, the average of granulated mast cells was significantly lower than degranulated mast cells. There was a significant difference between the average of degranulated mast cells in the diabetic animal using the base and control group. In the test-group DD (diabetics animals having received Oleuropein), on the second day, mast cells were significantly more than in the control group and diabetic animals which received base substanc and the group of healthy animals receiving Oleuropein. Conclusions. The findings of this study showed that the oleuropein extract significantly increased the mast cell count of samples taken from ulcers of diabetic mice. [ABSTRACT FROM AUTHOR]