Morphological study of the pituitary gland of the studanese Nile fish Clarias Lazera

C. lazera was studied using some standard techniques employed in the study of vertebrate pituitary. The pituitary gland is attached to the infundibular region of the brain by a cylindrical infundilbular stalk. The gland is composed of two main divisions; the pars glandularis and the pars nervosa. The former is subdivided into an anterior, middle and posterior glandular regions. The anterior glandular region is composed mostly of clusters of acidophils which surround blood capillaries, giving the region a follicular appearance. The middle region is composed of basophils, acidophils and chromophobes. The distribution of the three types of cells has no definite pattern. The basophils are characterized by possessing colloidal globules, and therefore such basophils are described as globular basophils. The posterior region is formed mostly of dull acidophils, with few interspersed dull faint basophils. The two types of cells are scattered singly or in groups arround the branches of the pars nervosa. The pars nervosa, which is the continuation of the infundibular stalk, form a central core around which the three glandular regions of the pituitary gland are arranged. The processes of the pars nervosa are elaborate, with a fanning root – like nature, in the posterior glandular region and scanty in both the anterior and middle glandular regions. The pars nervosa appears as a fibrous tissue with scattered nuclei belonging to neuroglia cells. It is characterized by the colloidal Herring materials, basophil and acidophilic glandular cells. Infundilbular stalk, which link the floor of hypothalamus and the terminal zone of the anterior glandular region was found to be a thin lamina of nervious tissue with a layer of epindymal cell lining the third ventricle. The middle glandular region was found to consist of three chromophils cells, only one type of acidophil was identified. It took both OG and erythrosin. The other two types were found to be basophilic and they were designated as type 2 and type 3. Basophils type 3 were PAS, AF positive but AB negative. The pars nervosa was found to be small, and contained more stainable neuro-secretory materials.

Comparison of the In Vitro and In Vivo Electrochemical Performance of Bionic Electrodes

The electrochemical performance of platinum electrodes was assessed in vitro and in vivo to determine the impact of electrode implantation and the relevance of in vitro testing in predicting in vivo behaviour. A significant change in electrochemical response was seen after electrode polarisation. As a result, initial in vitro measurements were poor predictors of subsequent measurements performed in vitro or in vivo. Charge storage capacity and charge density measurements from initial voltammetric measurements were not correlated with subsequent measurements. Electrode implantation also affected the electrochemical impedance. The typically reported impedance at 1 kHz was a very poor predictor of electrode performance. Lower frequencies were significantly more dependent on electrode properties, while higher frequencies were dependent on solution properties. Stronger correlations in impedance at low frequencies were seen between in vitro and in vivo measurements after electrode activation had occurred. Implanting the electrode increased the resistance of the electrochemical circuit, with bone having a higher resistivity than soft tissue. In contrast, protein fouling and fibrous tissue formation had a minimal impact on electrochemical response. In vivo electrochemical measurements also typically use a quasi-reference electrode, may operate in a 2-electrode system, and suffer from uncompensated resistance. The impact of these experimental conditions on electrochemical performance and the relevance of in vitro electrode assessment is discussed. Recommended in vitro testing protocols for assessing bionic electrodes are presented.

Hydrogel composite scaffolds achieve recruitment and chondrogenesis in cartilage tissue engineering applications

Background The regeneration and repair of articular cartilage remains a major challenge for clinicians and scientists due to the poor intrinsic healing of this tissue. Since cartilage injuries are often clinically irregular, tissue-engineered scaffolds that can be easily molded to fill cartilage defects of any shape that fit tightly into the host cartilage are needed. Method In this study, bone marrow mesenchymal stem cell (BMSC) affinity peptide sequence PFSSTKT (PFS)-modified chondrocyte extracellular matrix (ECM) particles combined with GelMA hydrogel were constructed. Results In vitro experiments showed that the pore size and porosity of the solid-supported composite scaffolds were appropriate and that the scaffolds provided a three-dimensional microenvironment supporting cell adhesion, proliferation and chondrogenic differentiation. In vitro experiments also showed that GelMA/ECM-PFS could regulate the migration of rabbit BMSCs. Two weeks after implantation in vivo, the GelMA/ECM-PFS functional scaffold system promoted the recruitment of endogenous mesenchymal stem cells from the defect site. GelMA/ECM-PFS achieved successful hyaline cartilage repair in rabbits in vivo, while the control treatment mostly resulted in fibrous tissue repair. Conclusion This combination of endogenous cell recruitment and chondrogenesis is an ideal strategy for repairing irregular cartilage defects. Graphical Abstract

Pulse dye laser therapy and superficial cryotherapy as a novel combination treatment for hypertrophic scars and keloids

Background: Hypertrophic scars are benign and fibrotic skin lesions caused by defects in the regulation of cellularity during the wound-healingprocess, in which there is higher collagen production and less degradation. Genetic predisposing factors and different skin injuries may play a role in developing these types of lesions. On the other hand, keloids are overgrowths of fibrous tissue outside the original boundaries of trauma, yet these may also occur spontaneously. There are numerous treatment options for both conditions, including silicone gel sheeting, pressure therapy, intralesional triamcinolone acetonide, radiation, laser therapy, cryosurgery, interferon, 5-fluorouracil, and surgical excision as well as a multitude of extracts and topical agents. Objective: The objective was to evaluate the effectiveness of pulse dye laser (PDL) therapy and superficial cryotherapy as a combination treatment for hypertrophic scars and keloids. Method: Four Arabic female patients were seen at the outpatient clinic of the Department of Dermatology at the King Fahd Hospital of the University in Khobar, Saudi Arabia. The patients had keloids and hypertrophic scars. Treatment with cryotherapy every week for three weeks followed by one session of pulsed dye laser was administered rotationally for three to six months until the lesions displayed remarkable physical improvement or complete resolution. Results: All patients experienced significant improvement, showing a reduction in the size, erythema, pliability, and pruritus. None of the hypertrophic scars or keloids deteriorated during the one year of treatment. No complications were noted during the treatment period. Conclusion: Sequential PDL therapy combined with superficial cryotherapy may be an option for treating hypertrophic scars and keloids.

Achieving stomal continence with an ileal pouch and a percutaneous implant

In this study, a soft-tissue-anchored, percutaneous port used as a mechanical continence-preserving valve in reservoir ileo- and urostomies was functionally and morphologically evaluated in eight dogs. During follow-up, the skin failed to attach to the implant, but the intestine inside the stoma port appeared to be attached to the mesh. After reaching adequate reservoir volume, the urostomies were rendered continent by attaching a lid to the implant. The experiments were ended at different time intervals due to implant-related adverse events. In only one case did the histological evaluation reveal integration at both the implant-intestine and implant-skin interfaces, with a low degree of inflammation and the absence of bacterial colonisation. In the remaining cases, integration was not obtained and instead mucosal downgrowth and biofilm formation were observed. The skin-implant junction was characterised by the absence of direct contact between the epidermis and the implant. Varying degrees of epidermal downgrowth, granulation tissue formation, inflammatory cell infiltration and bacterial growth and biofilm formation were prominent findings. In contrast, the subcutaneously located anchor part of the titanium port was well integrated and encapsulated by fibrous tissue. These results demonstrate the opportunity to achieve integration between a soft-tissue-anchored titanium port, skin and intestine. However, predictable long-term function could not be achieved in these animal models due to implant- and non-implant-related adverse events. Unless barriers at both the implant-skin and implant-intestine junctions are created, epidermal and mucosal downward migration and biofilm formation will jeopardise implant performance.

Confocal Microscopy of Filtering Blebs after Trabeculectomy

Introduction: Filtration surgery is the most effective method of lowering intraocular pressure (IOP) in patients with insufficient medical control. It consists in facilitating the drainage of the intraocular fluid (IOF) from the anterior chamber to the subconjunctival space and subsequent lowering of IOP. The formation of filtration blebs (FB) and the processes of scarring occurring in the conjunctiva are of particular importance in glaucoma surgery. In many cases, the appearance of FB does not match the IOP values, and what causes the failure after trabeculectomy often remains unclear. Often, over time, there is a change in the structure of the FB, as fibrous tissue grows, which prevents the IOF drainage. Laser scanning in vivo confocal microscopy is a non-invasive study allowing the production of layered images at the microstructural level with high resolution of both the cornea and other structures of the anterior ocular surface. Aim: To evaluate the morphological structure and function of filtering blebs after trabeculectomy using in vivo confocal microscopy taking into account the type of implant and when the surgery was performed. Materials and methods: The study included 33 patients, 46 eyes with glaucoma. Twenty-six of the eyes had primary open-angle glaucoma (POAG), 18 eyes had pseudoexfoliative glaucoma and 2 eyes had juvenile glaucoma. All patients underwent trabeculectomy with fornix-based flap, and three of the eyes underwent retrabeculectomy. Mitomicyn C (MMC) was administered intraoperatively to all patients. The study of the filtering bleb was performed by in vivo confocal microscopy (CFM) (Heidelberg Retina Tomograph II (HRT II) /Rostock Cornea Module/ (Heidelberg Engineering GmbH, Heidelberg, Germany), the period from trabeculectomy and examination being from 1 year to 22 years. An Express implant was placed in 14 eyes, Ologen implant in 7 eyes, and 25 eyes had no implant placed. In the analysis of the morphological structure of the filtering blebs, three indicators were evaluated: the type of epithelium, the type of stroma, and blood vessels. Results: Statistical significance was established with regard to the function and morphological structure of the filtering bleb (p=0.009). Blebs with fine collagen mesh and dense collagen mesh demonstrate good function. In the case of blebs with insufficient function, those with a dense collagen network and hyper-reflective tissue predominated and there were no blebs with a fine collagen network, and in non-functioning blebs most common were those with a pronounced collagen network and hyper-reflective tissue. With regard to vascularization, we found that the functioning blebs in the shortest postoperative period were dominated by those with one blood vessel (stage 1) and there was no stage 3, with weak tortuosity, while in non-functioning blebs in the late postoperative period, there was moderate to severe vascularization and tortuosity (p=0.037), (p=0.043), (p=0.047), (p=0.021). The type of implant affects the tortuosity of the blood vessels of the filtering bleb (p=0.026). The blebs with Express implants show a slight tortuosity, followed by the blebs with Ologen implants. The highest percentage of highly kinked blood vessels occurred in blebs without an implant. Conclusions: In vivo confocal microscopy is an innovative method which allows visualization of the internal structure of the filtering blebs at a cellular level, giving us a new insight into the ongoing healing processes, premising the function of the filtering blebs after glaucoma surgery.

MORPHOLOGICAL MONITORING OF EXPERIMENTAL LIVER FIBROSIS IN RATS

Background. Though thioacetamide (TAA)-induced liver fibrosis (LF) is recognized as a classical model of toxic liver damage, there is no literature data on the description of its successive stages of histological and ultrastructural changes in various cell populations involved in fibrosis. Objective. To conduct morphological monitoring of fibrosis formation in the liver of rats using the TAA model of LF based on histological and ultrastructural changes in hepatocytes and perisinusoidal lipocytes (HSC). Material and methods. The experiment was carried out on 18 sexually mature male rats. LF was modeled by intraperitoneal injection of 2% TAA solution at a dose of 10 ml / kg every other day. Light microscopy of semi-thin sections of the liver was performed, as well as electron microscopy of ultrathin sections. Results. The study of semi-thin sections of rat liver tissue from the control group showed a normal architecture of the parenchyma, a large number of HSCs containing large lipid droplets ("resting" phenotype), a very small amount of cytoplasmic matrix poor in membrane organelles. In the animals that were receiving TAA for 4 weeks, a mesenchymalepithelial transition of HSCs from the "resting" type to a fibrogenic state (fibrogenic phenotype) was recorded, that was accompanied by a gradual decrease in the number of retinol-containing drops and the appearance of fibroblastlike cells (FLC) in HSCs. In the animals, that were receiving TAA for 12 weeks, the pool of fibrogenic cells in the liver increased, a mesothelial-mesenchymal transition occurred, characterized by the mesothelial cell migration deeper into the parenchyma and their acquisition of a mesenchymal phenotype. Lipid containing activated FLC were also found in fibrous tissue around the central vein. Foci of hepatic tissue destruction caused by necrosis and apoptosis of hepatocytes were much more common. Conclusions. Administration of TAA induces liver fibrosis while histological and ultrastructural monitoring of the state of hepatocytes and HSCs allows to monitor all stages of fibrosis, clarifying the mechanisms of damage to intracellular organelles and variants of hepatocyte death. This model of LF in rats can be used to test new antifibrotic drugs.

Brenner tumors

Brenner tumors are rare ovarian neoplasms composed of ovarian transition cells surrounded by dense fibrous tissue. Most of them are small tumors (<2 cm), detected incidentally in asymptomatic women. Its predominantly fibrous content results in relatively low signal on T2 weighted images, establishing differential diagnosis with ovarian fibroma and thecoma. Their imaging features are very similar, the differentiation is based on secondary characteristics, such as signs or symptoms of estrogen excess and the presence of a second ovarian neoplasm, which has been reported in up to 30% of patients with Brenner tumor. Although originally thought to be universally benign, there have been scattered reports in the past decades of borderline and malignant forms of Brenner tumors.

Soft Tissue Tumor

Soft tissue tumors are a heterogeneous group of benign and malignant lesions that develop from a variety of nonepithelial, extraskeletal elements, including adipose tissue, smooth and skeletal muscle, tendons, cartilage, fibrous tissue, blood vessels, and lymphatic structures. The writing of this article includes various sources originating from scientific journals and government guidelines and related agencies. Source searches were carried out on online portals for journal publications such as Med Scape Google Scholar (scholar.google.com) and the National Centre for Biotechnology Information/NCBI (ncbi.nlm.nih.gov), with the keyword “Sensoric Nerve Trauma”. Soft tissue tumors (STT) can be benign or malignant, and benign soft tissue tumors are more common than malignant tumors with a ratio of 100: 1. In a study of 93 cases of soft tissue tumors, it was found that the incidence of benign tumors was 75.2% and malignant tumors were 24.8%. Soft tissue tumors are associated with genetic conditions, radiation, chronic lymphedema, environmental carcinogens, and infections.