Catfish Epidermal Club Cell Morphologic and Immunologic Attributes: Heterogeneous S-100 Immunoreactivity and Possible Neuroendocrine Function.

The fish epidermis (EP) contains several cell types, and it has several functional roles, though the secretory role prevails. The alarm or epidermal club cells (ECCs) represent a voluminous immune cell secreting an alarm substance. Our work targeted the histochemical and immunologic attributes of the ECCs in catfish. Matrix metalloproteinase (MMP-9) immunostaining revealed strong immunoreactive signals in the cytoplasm of all ECCs, while S-100 protein immunoreactivity selectively marked the ECCs. Individual ECCs exhibit intense S-100 immunoreactivity compared to neighboring ECCs. The difference in the intensity of the S-100 immunostaining was associated with the difference in the ECC size. This was confirmed by the semithin results where several developmental stages of ECCs could be distinguished. Some eosinophilic granular cells with their characteristic metachromatic granules were recorded juxtaposing the ECCs. Moreover, some free electron-dense granules could be demonstrated in the intercellular spaces surrounding the ECCs. Collectively, these findings suggest several functional profiles for the catfish ECCs depending on their developmental stage. Most importantly, S-100 immunoreactivity in the ECCs suggests its neuroendocrine function. Moreover, the difference in the intensity and polar distribution of S-100 staining is a sign of its role in the differentiation of the ECCs.

Multi-institutional search for patient factors associated with adverse events following tracheotomy.

BACKGROUND: Tracheotomy is a common procedure for otolaryngologists. The risk of complications is difficult to predict. This study aims to identify measurable preoperative indicators associated with adverse events following tracheotomy. METHODS: The charts of adults undergoing tracheotomy for respiratory failure at one of four university-affiliated hospitals between 1/2012 and 8/2018 were reviewed. Complications were analyzed in the context of demographics, physiologic parameters, and comorbidities. RESULTS: Among 507 tracheotomies performed, the most common complications included infection, bleeding, and cardiac arrest. Mortality was 39 % in patients with pulmonary hypertension, 42 % in those with ejection fraction ≤ 40 and 32 % in those with abnormal right ventricular function, double the rates in patients without each of these findings. CONCLUSION: Many critically ill tracheotomy patients experience significant rates of adverse events. Risk factors for mortality include ejection fraction ≤ 40, pulmonary hypertension, and abnormal ventricular function. These should be considered for use in preoperative counseling.

Pulmonary Guardians and Special Regulatory Devices in the Lung of Nile Monitor Lizard (Varanus niloticus) with Special Attention to the Communication Between Telocyte, Pericyte, and Immune Cells.

Monitor lizards are acclimatized to a variety of environments. Most of the monitor species are terrestrial, although there are arboreal and semiaquatic monitors. Such accommodation requires unique cellular structure and regulatory devices in various organs, particularly their lungs. This study aimed to report the pulmonary guardians and special regulatory devices that may guard and promote the function of the lungs of the Nile monitor lizards (Varanus niloticus). Specially structured vessels were recorded in the pulmonary tissue involving atypical glomus vessels, vessels with variable wall thickness, and a venule with specialized internal elastic membrane. Moreover, numerous lung resident guardians could be identified including both alveolar and interstitial macrophages, dendritic cells, mast cells, and B- and T-lymphocytes. Pericytes were demonstrated surrounding the capillary endothelium with a characteristic direct hetero-cellular junction with telocytes. Telocytes established a microenvironment through an indirect hetero-cellular junction with the interstitial macrophage, dendritic cells, and pneumocyte type II. Collectively, these data indicate a significant role played by the specially structured vessels and the resident immune cells in guarding the pulmonary tissue of the Nile monitor lizards and promoting its function. Telocytes are suggested to play a key role in angiogenesis and cellular communication to promote the function of the immune cells.

Histological, Histochemical, and Ultrastructural Approach to the Ductus Deferens in Male Nile Monitor Lizard (Varanus niloticus).

The ductus deferens is a fundamental part of the male genital tract and the continuation of the epididymal duct. As a male secondary sex organ, the ductus deferens plays a crucial role in the nourishment, storage, and maturation of spermatozoa. Some studies have provided information about the ductus deferens structure in reptiles; however, the full description of the ductus deferens remains to be clarified. The current study aimed to describe the Nile monitor lizard (Varanus niloticus) ductus deferens from histological, histochemical, and ultrastructural perspectives. The results revealed that the ductus deferens is formed histologically from two main cell types: principal and basal. The principal cells were tall and filled with periodic acid Schiff (+)/alcian blue (−) cytoplasmic granules. The basal cells were found just above the basement membrane. By transmission electron microscopy, the principal cells exhibited typical protein-secreting cell features. Additionally, some intraepithelial cells, such as halo cells, undifferentiated mesenchymal cells, and agranular leukocytes, were identified. This study presents the first detailed description of the Varanus niloticus ductus deferens. Further immunohistochemical studies are required to explore the function(s) of the cellular components.

Migrating and Nerve Fibers-Associated Eosinophilic Granule Cells in the Olfactory Organ of Catfish (Clarias garpienius): Light and Electron Microscopic Evidence.

Piscine mast cells or eosinophilic granule cells (EGCs) of fish are equivalent to the mammalian mast cells. Recently, a better understanding of EGCs functions is allowed because of the growing interest in fish models. Herein, we present a trial to furnish data regarding the distribution of the EGCs in the fish olfactory organ, an issue that has not been reported so far. Regarding their distribution, two kinds of EGCs had been identified. An intra-epithelial one was detected in the olfactory epithelium lining of the olfactory lamellae. The stromal one was identified in the connective tissue core of the olfactory lamellae and in the lamina propria underlying the olfactory epithelium. Some were detected in the capillary lumen. The cytoplasm of the EGCs reacted strongly with the MMP-9 antibody. Stimulating a migration perspective for the olfactory EGCs which was confirmed by their location in the blood capillaries. Several EGCs could be verified in close relation, some underneath the epineurium, with the nerve fiber. Mutually, this verifies the existence of intra-epithelial and stromal migrating EGCs in the catfish olfactory organ and their inclusion in the olfactory immune response. Additionally, this provides evidence for an immune­nervous interaction to influence both the immune reactions and the nervous scheme in catfish.

Modeling of the adsorption of a protein-fragment on kaolinite with potential antiviral activity.

This work aimed at studying the potentiality of interactions between kaolinite surfaces and a protein-fragment (350-370 amino acid units) extracted from the glycoprotein E1 in the transmembrane domain (TMD) of hepatitis C virus capsid. A computational work was performed for locating the potential electrostatic interaction sites between kaolinite aluminol and siloxane surfaces and the residues of this protein-fragment ligand, monitoring the possible conformational changes. This hydrated neutralized kaolinite/protein-fragment system was simulated by means of molecular modeling based on atomistic force fields based on empirical interatomic potentials and molecular dynamic (MD) simulations. The MD calculations indicated that the studied protein-fragment interacted with the kaolinite surfaces with an exothermic process and structural distortions were observed, particularly with the hydrophilic aluminol surface by favorable adsorption energy. The viral units isolation or trapping by the adsorption on the kaolinite nanoparticles producing structural distortion of the peptide ligands could lead to the blockage of the entry on the receptor and hence a lack of viral activity would be produced. Therefore, these findings with the proposed insights could be an useful information for the next experimental and development studies in the area of discovering inhibitors of the global challenged hepatitis and other pathogenic viruses based on the phyllosilicate surface activity. These MD studies can be extended to other viruses like the COVID-19 interacting with silicate minerals surfaces.

IoT Based Predictive Maintenance Management of Medical Equipment.

Technological advancements are the main drivers of the healthcare industry as it has a high impact on delivering the best patient care. Recent years witnessed unprecedented growth in the number of medical equipment manufactured to aid high-quality patient care at a fast pace. With this growth of medical equipment, hospitals need to adopt optimal maintenance strategies that enhance the performance of their equipment and attempt to reduce their maintenance costs and effort. In this work, a Predictive Maintenance (PdM) approach is presented to help in failure diagnosis for critical equipment with various and frequent failure mode(s). The proposed approach relies on the understanding of the physics of failure, real-time collection of the right parameters using the Internet of Things (IoT) technology, and utilization of machine learning tools to predict and classify healthy and faulty equipment status. Moreover, transforming traditional maintenance into PdM has to be supported by an economic analysis to prove the feasibility and efficiency of transformation. The applicability of the approach was demonstrated using a case study from a local hospital in the United Arab Emirates (UAE) where the Vitros-Immunoassay analyzer was selected based on maintenance events and criticality assessment as a good candidate for transforming maintenance from corrective to predictive. The dominant failure mode is metering arm belt slippage due to wear out of belt and movement of pulleys which can be predicted using vibration signals. Vibration real data is collected using wireless accelerometers and transferred to a signal analyzer located on a cloud or local computer. Features extracted and selected are analyzed using Support Vector Machine (SVM) to detect the faulty condition. In terms of economics, the proposed approach proved to provide significant diagnostic and repair cost savings that can reach up to 25% and an investment payback period of one year. The proposed approach is scalable and can be used across medical equipment in large medical centers.

Gynecology Imaging Reporting and Data System (GI-RADS): diagnostic performance and inter-reviewer agreement.

OBJECTIVE: To evaluate diagnostic performance and inter-reviewer agreement (IRA) of the Gynecologic Imaging Reporting and Data System (GI-RADS) for diagnosis of adnexal masses (AMs) by pelvic ultrasound (US). PATIENTS AND METHODS: A prospective multicenter study included 308 women (mean age, 41 ± 12.5 years; range, 15-73 years) with 325 AMs detected by US. All US examinations were analyzed, and AMs were categorized into five categories according to the GI-RADS classification. We used histopathology and US follow-up as the reference standards for calculating diagnostic performance of GI-RADS for detecting malignant AMs. The Fleiss kappa (κ) tests were applied to evaluate the IRA of GI-RADS scoring results for predicting malignant AMs. RESULTS: A total of 325 AMs were evaluated: 127 (39.1%) were malignant and 198 (60.9%) were benign. Of 95 AMs categorized as GI-RADS 2 (GR2), none was malignant; of 94 AMs categorized as GR3, three were malignant; of 13 AMs categorized as GR4, six were malignant; and of 123 AMs categorized as GR5, 118 were malignant. On a lesion-based analysis, the GI-RADS had a sensitivity, a specificity, and an accuracy of 92.9%, 97.5%, and 95.7%, respectively, when regarding only those AMs classified as GR5 for predicting malignancy. Considering combined GR4 and GR5 as a predictor for malignancy, the sensitivity, specificity, and accuracy of GI-RADS were 97.6%, 93.9%, and 95.4%, respectively. The IRA of the GI-RADS category was very good (κ = 0.896). The best cutoff value for predicting malignant AMs was >GR3. CONCLUSIONS: The GI-RADS is very valuable for improving US structural reports. KEY POINTS: • There is still a lack of a standard in the assessment of AMs. • GI-RADS is very valuable for improving US structural reports of AMs. • GI-RADS criteria are easy and work at least as well as IOTA.

Onset of Appearance and Potential Significance of Telocytes in the Developing Fetal Lung.

CD34, vimentin, and vascular endothelial growth factor immunohistochemical analysis and electron microscopic tools were employed to record the initial appearance of telocytes (TCs) and stage-by-stage variations in TC localizations in the developing rabbit lung. TCs could not be identified in the primitive embryonic lung until day 18 of gestation. In the pseudoglandular lung, CD34+ TCs had been recorded under the cartilage of the main bronchus, in the wall of large-sized pulmonary vessels and large epithelial tubes. In the canalicular phase, TCs could be demonstrated in the smooth muscle layer of the bronchioles including the terminal ones. The strength of CD34 immunoreactive signals had been amplified by age until the day of parturition. Ultrastructurally, TCs consisted of a tiny body and exceptionally long telopodes (Tps). The Tp consisted of alternating thin segments (podomers) and dilated ones (podoms). The Tp sometimes branched with a dichotomous pattern. TCs interconnected in a network either by homocellular junctions with neighboring TCs or by heterocellular junctions with smooth muscle cells and alveolar cells. Collectively, early detection of TCs in pulmonary vessels suggests a potential role for TCs in their angiogenesis. For the lung tissue, TCs seem to be involved in the regulation of lung histogenesis.

A Complicated Case of Congenital Nasal Pyriform Aperture Stenosis: Use of a Long-term Unilateral Nasal Stent.

This case describes a full-term baby with pyriform aperture stenosis who failed intranasal dexamethasone and reflux therapy. She underwent repair via a sublabial approach and inferior turbinate reduction. Symptoms initially improved but she was unable to be weaned from intranasal steroids. Three subsequent surgeries ensued, including lysis of synechiae, further turbinate reduction, and placement of custom nasal stents, which failed as they became clogged frequently and were easily dislodged, leading to increased intranasal manipulation and postprocedural inflammation. She was eventually fitted and discharged with a large, unilateral stent. After 8 weeks, the stent was removed; she was tolerating full oral feeds. This case highlights the limitations of surgical repair and describes nontraditional uses of stenting.

Defining value-driven care in head and neck oncology.

In the USA, increasing attention is being paid to adopting a value-based framework for measuring and ultimately improving health care delivery. Value is defined as the benefit achieved relative to costs. The numerator of the value equation includes quality of care and outcomes achieved. The denominator includes costs, both financial costs and harms of treatment. Herein, we describe these elements of value as they pertain to head and neck cancer. A particular focus is to identify areas of the value equation where physicians have some control. We examine quality in each of three dimensions: structure, process, and outcomes. We also adopt Porter's three-tiered hierarchy of outcomes model, with specific outcomes relevant to patients with head and neck and thyroid cancer. Finally, we review issues related to costs and harms. We believe these findings can serve as a framework for further efforts to drive value-based delivery of head and neck cancer care.

SOLD1 is expressed in bovine trophoblast cell lines and regulates cell invasiveness.

BACKGROUND: Secreted protein of Ly-6 domain 1 (SOLD1), a secretory-type member of the Ly-6 superfamily, is expressed in both fetal and maternal tissues throughout gestation. SOLD1 mRNA is expressed in the endometrium and in trophoblast mononucleate and binucleate cells, suggesting it plays an important role not only in placental architecture at early gestation, but also in remodeling the endometrium at late gestation. Here, we investigate the expression of SOLD1 mRNA and protein in trophoblast cell lines. In addition, we examine the effect of SOLD1 on the invasive ability of trophoblast cells. METHODS: We measured SOLD1 gene expression in thirteen bovine trophoblast (BT) cell lines by using quantitative reverse transcription PCR (qRT-PCR). SOLD1 protein levels were examined in two cell lines, BT-C and BT-K, by using Western blotting and immunocytochemistry. In addition, we measured the invasive activity of BT cells in the presence or absence of anti-bovine SOLD1 antibodies. RESULTS: At variable levels, SOLD1 was expressed in all thirteen cell lines; however, expression remained below that of proximal fetal membrane tissue. SOLD1 protein, which was approximately 28 kDa in size, was detected in perinuclear area of the cytoplasm in BT cells. Treatment with anti-bovine SOLD1 antibody had a dose-dependent suppressive effect on the invasiveness of BT-K cell lines. CONCLUSIONS: The present study is the first to investigate SOLD1 expression in vitro, in trophoblastic cell lines. Our data suggested that SOLD1 is involved in the regulation of the trophoblast invasiveness. Therefore, SOLD1 may play an active and crucial role in mediating communication at the fetomaternal interface.

Yield and Energy Modeling for Biochar and Bio-Oil Using Pyrolysis Temperature and Biomass Constituents.

Pyrolysis offers a sustainable and efficient approach to resource utilization and waste management, transforming organic materials into valuable products. The quality and distribution of the pyrolysis products highly depend on the constituents' properties and set process parameters. This research aims to investigate and model this dependency, offering decision-makers a tool to guide them when designing the process for a particular application. Experimental data on the pyrolysis of various types of feedstocks processed at a wide range of pyrolysis temperatures (350-650 °C) are utilized to develop the prediction models. Four variables are modeled: the yield and energy content for both the biochar and bio-oil as a function of the pyrolysis temperature and feedstock characteristics. The models developed had very good prediction power with the coefficient of determination above 90%. The results highlight the advantages of food waste (leftover) as a suitable feedstock to produce biochar at the pyrolysis temperature within the range of 450-550 °C. Furthermore, the biofuels produced from food waste are found to be of good quality, with the bio-oil exceptionally high in energy content (HHV = 34.6 MJ/kg), which is almost 80% of that of diesel. The developed models provide a tool for predicting the biofuel yield and quality based on the feedstock selection and process temperature.

Successful treatment of pseudomyxoma peritonei (PMP) through cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC): A case report and literature review.

INTRODUCTION AND IMPORTANCE: Pseudomyxoma peritonei (PMP) is characterized by the accumulation of mucinous fluid in the abdominal cavity, typically originating from mucin-producing tumors, most commonly arising in the appendix. CASE PRESENTATION: A 63-year-old male patient presented to the hospital with complaints of abdominal pain, significant weight loss, a palpable mass in the right iliac fossa, and evidence of ascites. A diagnosis of PMP was proposed based on findings from a computed tomography (CT) scan, which was subsequently confirmed through histopathological examination of a biopsy. The patient underwent successful treatment with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS-HIPEC). CLINICAL DISCUSSION: Diagnosing PMP presents challenges due to its rarity and the potential for extensive spread throughout the peritoneal cavity, necessitating a multidisciplinary approach for successful treatment. CONCLUSION: Pseudomyxoma peritonei is a rare yet medically significant condition. Documenting a case of this ailment in Palestine has the potential to advance medical understanding, raise awareness, and improve patient care standards within the local healthcare system. By documenting this uncommon condition, healthcare practitioners in Palestine can gain valuable insights into its manifestations, diagnostic processes, and treatment modalities. This contribution not only enriches the global medical literature but also promotes collaboration in addressing the challenges associated with rare diseases.

Structural characteristics and regenerative potential: Insights from the molly fish spinal cord.

Unlike mammals, species such as fish and amphibians can regenerate damaged spinal cords, offering insights into potential therapeutic targets. This study investigates the structural features of the molly fish spinal cord through light and electron microscopy. The most notable characteristic was the presence of Mauthner cells (M-cells), which exhibited large cell bodies and processes, as well as synaptic connections with astrocytes. These astrocytic connections contained synaptic vesicles, suggesting electrical transmission at the M-cell endings. Astrocytes, which were labeled with glial fibrillary acidic protein (GFAP), contained cytoplasmic glycogen granules, potentially serving as an emergency fuel source. Two types of oligodendrocytes were identified: a small, dark cell and a larger, lighter cell, both of which reacted strongly with oligodendrocyte transcription factor 2 (Olig2). The dark oligodendrocyte resembled human oligodendrocyte precursors, while the light oligodendrocyte was similar to mature human oligodendrocytes. Additionally, proliferative neurons in the substantia grisea centralis expressed myostatin, Nrf2, and Sox9. Collectively, these findings suggest that the molly fish spinal cord has advanced structural features conducive to spinal cord regeneration and could serve as an excellent model for studying central nervous system regeneration. Further studies on the functional aspects of the molly fish spinal cord are recommended. RESEARCH HIGHLIGHTS: Mauthner cells (M-cell), with their typical large cell body and processes, were the most characteristic feature in Molly fish spinal cord, where it presented synaptic connections with astrocytes and their ends contained synaptic vesicles indicating an electrical transmission in the M-cells endings. Two types of oligodendrocytes could be recognized; both reacted intensely with Oligodendrocyte transcription factor 2 (Olig2). The proliferative neurons of the substantia grisea centralis expressed myostatin, Nrf2, and Sox9. The findings of this study suggest that molly fish possess highly developed structural features conducive to spinal cord regeneration. Consequently, they could be deemed an exemplary model for investigating central nervous system regeneration.

The potential Association of Bisphenol A exposure and type 1 diabetes mellitus among Dakahlia Governorate's children sample, Egypt.

Background: Bisphenol A (BPA) is an endocrine disrupter affecting glucose homeostasis. Objectives: This study aimed to investigate BPA's relationship with Type 1 Diabetes Mellitus (T1DM) in Dakahlia Governorate's children, in Egypt. Subjects materials and methods: The study had two parts: clinical and experimental. Clinical Study was conducted on 200 children, equally divided into control and T1DM groups. They underwent: demographic data, height, weight, body mass index, glycosylated HbA1C, random blood glucose, and urinary BPA measurements. Experimental Study was conducted on 60 adult albino rats. Rats were randomly divided into three equal groups: control group: received 0.5 mL of pure olive oil, group 1: received 20 mg/kg/day BPA, and group 2: received 100 mg/kg/day BPA orally for 6 weeks. Fasting and two hours postprandial glucose levels were measured at the beginning and end of the study. Histopathological examination and imaging study of the pancreas were done. Results: In clinical study: HbA1C and random blood glucose levels in diabetic children showed a significant increase compared to control. Children in control group showed controlled HbA1C, while the T1DM group showed 86% with poor diabetic control. There was a significant increase in BPA level in the T1DM group compared to the control. Rats that received BPA showed a marked increase in fasting and two hours postprandial glucose levels, histopathological changes in the pancreas with more changes determined in the high dose group, and a significant decrease in the islets of Langerhans diameters with group 2 more affected. Conclusion: So, BPA exposure could be considered a risk factor for T1DM in children.

Nurses' knowledge of medical device-related pressure injuries and risk factors: A descriptive study at a large medical centre from Palestine.

BACKGROUND: Nurses' knowledge of pressure injuries causes and risk factors helps to prevent their occurrences and protect the patient. AIM: To assess the level of knowledge of medical device-related pressure injuries and to identify risk factors that affect the knowledge. METHODS: A cross-sectional design was used in this study considering a convenience sample from critical care nurses. The nurses were invited to complete the Medical Device-Related Pressure Injuries Knowledge Questionnaire. RESULTS: About 71 nurses participated in the study. The mean score of MDRPI_KQ was 23.28 ± 4.14 out of 36. Mann-Whitney Test did not show statistically significant relationships between the MDRPI_KQ mean score and related variables (p > 0.05). The regression results indicated that the three predictors explained 46.4% of the variance (R2 = 0.215, F(3, 6.114) = 3.75, p = 0.001). It was found that the Frequency of encountering a patient with MDRPIs significantly predicted MDRPI_KQ score, job position, and assuming the care responsibility for MDRPIs in the department. CONCLUSIONS: Poor knowledge of pressure injuries can negatively affect patient care so training programs and policies should be developed based on the level of knowledge and practices of the staff to be more effective.

A machine learning approach on chest X-rays for pediatric pneumonia detection.

Background: According to the World Health Organization (WHO), pneumonia is the leading infectious cause of death in children below 5 years old. Hence, the early detection of pediatric pneumonia is crucial to reduce its morbidity and mortality rates. Even though chest radiography is the most commonly employed modality for pneumonia detection, recent studies highlight the existence of poor interobserver agreement in the chest X-ray interpretation of healthcare practitioners when it comes to diagnosing pediatric pneumonia. Thus, there is a significant need for automating the detection process to minimize the potential human error. Since Artificial Intelligence tools such as Deep Learning (DL) and Machine Learning (ML) have the potential to automate disease detection, many researchers explored how such tools can be implemented to detect pneumonia in chest X-rays. Notably, the majority of efforts tackled this problem from a DL point of view. However, ML has shown a higher potential for medical interpretability while being less computationally demanding than DL. Objective: The aim of this paper is to automate the early detection process of pediatric pneumonia using ML as it is less computationally demanding than DL. Methods: The proposed approach entails performing data augmentation to balance the classes of the utilized dataset, optimizing the feature extraction scheme, and evaluating the performance of several ML models. Moreover, the performance of this approach is compared to a TL benchmark to evaluate its candidacy. Results: Using the proposed approach, the Quadratic SVM model yielded an accuracy of 97.58%, surpassing the accuracies reported in the current ML literature. In addition, this model classification time was significantly smaller than that of the TL benchmark. Conclusion: The results strongly support the candidacy of the proposed approach in reliably detecting pediatric pneumonia.

Ovary of Zebrafish during Spawning Season: Ultrastructure and Immunohistochemical Profiles of Sox9 and Myostatin.

This study sought to examine the ovarian cellular and stromal components of the zebrafish (Danio rerio) throughout the spawning season using light and electron microscopic tools. The ovaries of zebrafish showed oocytes in all stages of follicular development and degeneration (atresia). Six stages of oogenesis were demonstrated: oogonia, early oocytes, late oocytes, vacuolated follicles, the yolk globule stage (vitellogenesis), and mature follicles. The SOX9 protein was expressed in the ooplasm of the primary and previtellogenic oocytes and the theca cell layer of the mature follicles. Myostatin was expressed in the granulosa and theca cells. Many stem cells in the ovarian stroma expressed myostatin and SOX9. During the spawning season, the EM results indicated that the zona radiata increased in thickness and was crossed perpendicularly by pore canals that contained processes from both oocytes and zona granulosa. The granulosa cells contained many mitochondria, rER, sER, and vesicles. Meanwhile, the thecal layer consisted of fibroblast-like cells. Atretic follicles could be demonstrated that involved both oocytes and their follicular walls. Several types of cells were distinguished in the ovarian stroma, including mast cells, telocytes, lymphocytes, fibroblasts, endocrine cells, macrophages, adipocytes, dendritic cells, and steroidogenic (stromal) cells. The ovary of the zebrafish serves as a model to investigate follicular development.

The relationship between ovarian hormones and mast cell distribution in the ovaries of dromedary camel (Camelus dromedaries) during the follicular wave.

Background and Aim: Mast cells (MCs) play an essential role in regulating tissue homeostasis through various non-allergic immune reactions. This study aimed to describe the salient features of MCs during different phases of the estrous cycle and evaluate the relationship between ovarian hormones and the presence of MCs in camel ovaries. Materials and Methods: Genital tracts (n = 28) of healthy, non-pregnant camels were collected from a local slaughterhouse. The follicular wave stage was determined according to structures on the ovaries using an ultrasound device. Stages were classified as "growing" (n = 12, FØ = 0.3-0.8 cm), "mature" (n = 9, FØ = 0.9-2.2 cm), or "regression" phase (n = 7, FØ >2.5). Blood samples were collected at slaughter to determine serum estradiol-17ß and progesterone levels using an immunoassay. Safranin-O, periodic acid/Schiff, alcian blue, or methylene blue stains were used to detect MCs. Results: Follicular numbers at the growing, mature, and regression phases were determined to be 36, 14, and 7 follicles, respectively. Mast cells were widely but sparsely distributed within the ovarian tissue (9.3 MCs in the growing phase, 10.7 in the mature phase, and 7.0 in the regression phase). Typical histological features of MCs were observed in ovarian stromal tissue. Some MCs were found in the interstitial tissue, either near the follicular wall or the interstitial gland. Mast cells were present at a higher density during the mature phase than in the growing and regression phases in the ovarian matrix. A significantly reduced presence of MCs was found in the regression phase than in both the growing and mature phases (p < 0.05). A very strong positive correlation was observed between serum estradiol-17ß concentrations and MC density in the ovaries (r = 0.9; p < 0.001). In addition, a strong negative correlation (r = -0.65; p = 0.03) was observed between the presence of MCs and serum progesterone concentrations. Conclusion: These findings suggest that the follicular wave phase and the associated hormonal concentration induce changes in the number of MCs in the camel ovary.