Search Results (19)

(1) Background: The sophisticated function of the aortic root relies on the coordinated movement of its constituent components. This study examines the extracellular components of the interleaflet triangles (ILTs) and characterises the cells that are present within this region of the aortic root. (2) Methods: A total of 10 human aortic valves and 6 porcine aortic valves were processed for immunohistochemical staining, scanning, and transmission electron microscopy. (3) Results: The three ILTs differed in size and macroscopic appearance. Each triangle comprised up to five distinct layers of tissue: an innermost endothelial layer, an inner elastin-rich layer, a thicker outer layer comprising densely packed layers of collagen and glycosaminoglycans, and an outer layer of intermingled myocardial and adipose tissue. A band of cells near the luminal surfaces of all ILTs expressed smooth muscle cell α-actin with variable expression of smooth muscle myosin heavy chain. In all the ILTs, there was evidence of neurofilament staining, indicating the presence of nerve fibres. (4) Conclusions: Each ILT is unique in its structure and organisation, with differing amounts of elastin and collagen, as well as myocardial, adipose, and fibrous content. The ILTs contain multiple cell types in varying abundance. Functional studies are required to determine the role of the different cells and their organisation in contributing to the sophisticated, dynamic behaviour of the aortic root. Full article

Background: Patients suffering from a new variant of endemic pemphigus foliaceus in El Bagre, Colombia, South America (El Bagre-EPF) produce autoantibodies (Abs) to different proteins in the skin (frustre form), as well as to those in other organs (Senear–Usher-like and systemic forms). Here, we hypothesize whether patients’ autoantibodies play a role in triggering epicardium and pericardium autoimmunity and pathogenicity. We based this hypothesis on knowing that these patients frequently show clinical symptoms of the chest and heart, and we hypothesize that the autoantibodies of this disease are the main contributors to the base of the pericardial conditions of these patients. Materials and Methods: A case-control study for testing the sera of patients affected by El Bagre-EPF (n = 45) and matched controls from the endemic area (n = 45) was conducted to evaluate reactivity with the pericardial tissue. Patients’ necropsies were tested by immunohistochemistry (IHC), in El Bagre-EPF patients (n = 7) and matched controls. Results: The sera from most El Bagre-EPF patients displayed polyclonal autoreactivity with both layers of the pericardium, i.e., fibrous pericardium and serous pericardium (mainly to cell junctions and sensory nerve formations), as well as with the neurovascular cell junction branches. Controls were negative (p < 0.1). These reactivities were detected by IIF, CM, and IHC using secondary Abs against total IgG, IgM, Kappa and lambda, C3C of the complement, fibrinogen, and albumin. Furthermore, Abs against MIZAP, ARVCF, desmoplakin I-II, and p0071 colocalized with the Abs of El Bagre-EPF (p < 0.1). Conclusions: Patients affected by El Bagre-EPF produce autoantibodies directed against molecules present in the cell junctions of the pericardium and adnexal structures. Further studies will focus on the clinical significance of these findings. Full article

Background: Fibrous dysplasia (FD) is often difficult for skull base surgeons to address. FD arises due to the abnormal proliferation of fibroblasts, ultimately resulting in immature osseous tissue replacing normal cancellous bone. When the skull base is involved, it can result in cranial nerve compression. FD affecting the optic canal and optic nerve is the most concerning as new onset of vision loss is considered a surgical emergency. The prevalence of FD is approximately 3.6 per 1,000,000. The most severe implications of this disease are neurological deficits due to cranial nerve compression, cosmetic appearance, and high recurrence rates even in the setting of surgical and medical therapy interventions. Methods: A PubMed search of “pediatric fibrous dysplasia management” using MESH Terms was conducted. Articles were excluded for non-English languages, inaccessibility, and events/erratum/letters to the editor. Included articles were in English, as well as encompassed pediatric FD case reports or comprehensive reviews of FD that discussed pediatric presentations. Results: A total of 109 articles were reviewed, and 44 were included in the final review. Most articles were case reports. There is a clear need for guidelines regarding surgical intervention, especially in the pediatric population, where hormonal fluctuation can influence rates of recurrence and bony deformity. Overall, most surgeons recommend close observation with biomarkers and radiographic imaging for asymptomatic patients until at least the age of 16 years old. Conservative methods, such as RANK-L inhibitors, can be utilized to decrease growth with some success, especially in older adolescents. Conclusion: This review is an update on this disease and its presentations, imaging findings, and treatment options. The current literature lacks clear guidance on management, especially in regard to surgical intervention or recurrence monitoring algorithms. Full article

Laminectomy is a commonly performed surgical procedure by orthopedic and neurosurgeons, aimed at alleviating nerve compression and reducing pain. However, in some cases, excessive proliferation of fibrous scar tissue in the epidural space post-surgery can lead to persistent and intractable lower back pain, a condition known as Failed Back Surgery Syndrome (FBSS). The persistent fibrous tissue causes both physical and emotional distress for patients and also makes follow-up surgeries more challenging due to reduced visibility and greater technical difficulty. It has been established that the application of biomaterials to prevent epidural fibrosis post-lumbar surgery is more beneficial than revision surgeries to relieve dural fibrosis. Hydrogel-based biomaterials, with their excellent biocompatibility, degradability, and injectability and tunable mechanical properties, have been increasingly introduced by clinicians and researchers. This paper, building on the foundation of epidural fibrosis, primarily discusses the strategies for the preparation of natural and polymeric biomaterials to prevent epidural fibrosis, their physicochemical properties, and their ability to mitigate the excessive proliferation of fibroblasts. It also emphasizes the challenges that need to be addressed to translate laboratory research into clinical practice and the latest advancements in this field. Full article

The ligament of Marshall is an epicardial structure characterized by its composition of fat, fibrous tissue, blood vessels, muscle bundles, nerve fibers, and ganglia. Its intricate network forms muscular connections with the coronary sinus and left atrium, alongside adjacent autonomic nerves and ganglion cells. This complexity plays a pivotal role in initiating focal electrical activities and sustaining micro- and macro-reentrant circuits, thereby contributing to the onset of atrial fibrillation and atrial tachycardia. However, endocardial ablation in this area may encounter challenges due to anatomical variations and insulation by fibrofatty tissue. Combining ethanol infusion into the vein of Marshall with radiofrequency ablation presents a promising strategy for effectively and safely eliminating this arrhythmogenic structure and terminating associated tachycardias. Full article

Infiltrative lipomas, which are locally invasive tumors composed of well-differentiated adipocytes, are histologically identical to lipomas but have a tendency to infiltrate adjacent muscle and fibrous tissue without metastasis, such as muscle; connective tissue; bone; and, in rare cases, peripheral nerves and the spinal cord. They differ from liposarcomas yet also exhibit neoplastic cell infiltration and often recur despite surgical removal. A 10-year-old spayed Maltese female dog presented with hindlimb paresis and back pain for two months. Computed tomography and magnetic resonance imaging revealed an extensive fatty mass impinging on the vertebral canal, compressing the spinal cord, and extending into the surrounding muscle layers and thoracic cavity. The mass was surgically removed, and subsequent postoperative computed tomography confirmed complete removal of the mass using Vitrea^® advanced visualization fat measurement. Histopathological analysis confirmed that the mass was an infiltrative lipoma. The patient’s symptoms completely resolved after surgery, with no recurrence reported at the 2-year follow-up. This case highlights the benefits of using postoperative computed tomography combined with the automated fat measurement technique to determine whether reoperation is necessary or to predict patient prognosis by identifying potential residual lipoma post-surgery. Full article

Lipofibromatous hamartoma, first reported in 1953, is a rare, slowly progressive soft tissue tumor, the characteristics of which include the enlargement of the affected nerve via the epineurial and perineurial proliferation of adipose and fibrous tissues. Out of 200 previously reported cases of lipofibromatous hamartoma of the median nerve, there have been approximately 25 pediatric cases under the age of 18. Herein, we report a case of lipofibromatous hamatoma of the median nerve in a 3-year-old female patient who was surgically decompressed via carpal tunnel release and epineurolysis. The patient was followed-up on an outpatient clinic basis annually with sonographic evaluations, and the postoperative 10th-year follow-up did not show recurrence or any deficits in motor and sensory functions. Full article

Several solid lesions can be found within the pancreas mainly arising from the exocrine and endocrine pancreatic tissue. Among all pancreatic malignancies, the most common subtype is pancreatic ductal adenocarcinoma (PDAC), to a point that pancreatic cancer and PDAC are used interchangeably. But, in addition to PDAC, and to the other most common and well-known solid lesions, either related to benign conditions, such as pancreatitis, or not so benign, such as pancreatic neuroendocrine neoplasms (pNENs), there are solid pancreatic lesions considered rare due to their low incidence. These lesions may originate from a cell line with a differentiation other than exocrine/endocrine, such as from the nerve sheath as for pancreatic schwannoma or from mesenchymal cells as for solitary fibrous tumour. These rare solid pancreatic lesions may show a behaviour that ranges in a benign to highly aggressive malignant spectrum. This review includes cases of an intrapancreatic accessory spleen, pancreatic tuberculosis, solid serous cystadenoma, solid pseudopapillary tumour, pancreatic schwannoma, purely intraductal neuroendocrine tumour, pancreatic fibrous solitary tumour, acinar cell carcinoma, undifferentiated carcinoma with osteoclastic-like giant cells, adenosquamous carcinoma, colloid carcinoma of the pancreas, primary leiomyosarcoma of the pancreas, primary and secondary pancreatic lymphoma and metastases within the pancreas. Therefore, it is important to determine the correct diagnosis to ensure optimal patient management. Because of their rarity, their existence is less well known and, when depicted, in most cases incidentally, the correct diagnosis remains challenging. However, there are some typical imaging features present on cross-sectional imaging modalities that, taken into account with the clinical and biological context, contribute substantially to achieve the correct diagnosis. Full article

Soft tissue regeneration holds significant promise for addressing various clinical challenges, ranging from craniofacial and oral tissue defects to blood vessels, muscle, and fibrous tissue regeneration. Mesenchymal stem cells (MSCs) have emerged as a promising tool in regenerative medicine due to their unique characteristics and potential to differentiate into multiple cell lineages. This comprehensive review explores the role of MSCs in different aspects of soft tissue regeneration, including their application in craniofacial and oral soft tissue regeneration, nerve regeneration, blood vessel regeneration, muscle regeneration, and fibrous tissue regeneration. By examining the latest research findings and clinical advancements, this article aims to provide insights into the current state of MSC-based therapies in soft tissue regenerative medicine. Full article

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. Full article

Background and Objectives: Melorheostosis, also referred to in the literature as Leri’s disease, is an unusual mesenchymal dysplasia with the clinical appearance of benign sclerosing bone dysplasia; it frequently occurs in late adolescence. Any bone in the skeletal system can be affected by this disease, though the long bones of the lower extremities are the most common, at any age. Melorheostosis has a chronic evolution, and symptoms are usually absent in the early stages. The etiopathogenesis is still unknown, however, numerous theories have been proposed that could explain the appearance of this lesion formation. An association with other benign or malignant bone lesions is also possible, and associations with osteosarcoma, malignant fibrous histiocytoma, or Buschke–Ollendorff syndrome have also been reported. There have also been reported cases of the malignant transformation of a pre-existing melorheostosis lesion into malignant fibrous histiocytoma or osteosarcoma. The diagnosis of melorheostosis can be made only based on radiological images, but, due to its polymorphism, additional imaging investigations are often necessary and sometimes only a biopsy can establish a definite diagnosis. Because there are currently no guidelines for treatment based on scientific evidence, due to the low number of cases diagnosed worldwide, our objective was to highlight the early recognition and specific surgical treatments for better prognosis and outcomes. Materials and Methods: We conducted a review of the literature consisting of original papers, case reports, and case series and presented the clinical and paraclinical characteristics of melorheostosis. We aimed to synthesize the treatment methods available in the literature as well as determine possible future directions related to the treatment of melorheostosis. Furthermore, we presented the results of a case of femoral melorheostosis admitted to the orthopedics department of the University Emergency Hospital of Bucharest in a 46-year-old female patient with severe pain in the left thigh and limitation of joint mobility. Following the clinical examination, the patient complained of pain in the middle third of the left thigh in the antero-medial compartment; the pain appeared spontaneously and was aggravated during physical activity. The pain started about two years prior, but the patient experienced complete pain relief after the administration of non-steroidal anti-inflammatory drugs. In the last six months, the patient presented an increase in pain intensity without significant improvement following the administration of non-steroidal anti-inflammatory drugs. The patient’s symptoms were mainly determined by the increase in the volume of the tumor and the mass effect on the adjacent tissues, especially on the vessels and the femoral nerve. The CT examination and bone scintigraphy showed a unique lesion in the middle third of the left femur and no oncological changes in the thoracic, abdominal, and pelvic regions; however, at the level of the femoral shaft, there was a localized cortical and pericortical bone lesion formation that surrounded approximately 180 degrees of the femoral shaft (anterior, medial, and lateral). It had a predominantly sclerotic structure but was associated with lytic areas with thickening of the bone cortex and areas of periosteal reaction. The next therapeutic gesture was to perform an incisional biopsy using a lateral approach at the level of the thigh. The histopathological result supported the diagnosis of melorheostosis. Additionally, immunohistochemical tests completed the data obtained after the microscopic examination through the classic histopathological technique The patient was discharged and included in a full medical recovery program for eight weeks in a specialized medical center, during which she also received analgesic treatment in maximum doses, but without improvement regarding her symptoms. Taking into account the chronic evolution of the pain, the complete lack of response to conservative treatment after eight weeks, and the lack of treatment guidelines in the case of melorheostosis, a surgical approach needed to be considered. The surgical option in this case, considering the circumferential location of the lesion at the level of the femoral diaphysis, was a radical resection. The surgical approach consisted of segmental resection to healthy bone tissue and reconstruction of the remaining defect with a modular tumoral prosthesis. At the 45-day postoperative control, the patient no longer complained of pain in the operated-on limb and was mobile with full support without gait difficulties. The follow-up period was one year, and the patient presented complete pain relief and a very good functional outcome. Results: In the case of asymptomatic patients, conservative treatment seems to be a good option with optimal results. However, for benign tumors, it remains unclear whether radical surgery is a viable option. Conclusions: Melorheostosis remains an incompletely understood disease, given the limited number of cases worldwide, and thus, there is a lack of clinical guidelines regarding specialized treatment. Full article

Fibrous structures with anisotropic fillers as composites have found increasing interest in the field of biofabrication since they can mimic the extracellular matrix of anisotropic tissues such as skeletal muscle or nerve tissue. In the present work, the inclusion of anisotropic fillers in hydrogel-based filaments with an interpenetrating polymeric network (IPN) was evaluated and the dynamics of such fillers in the composite flow were analyzed using computational simulations. In the experimental part, microfabricated rods (200 and 400 μm length, 50 μm width) were used as anisotropic fillers in extrusion of composite filaments using two techniques of wet spinning and 3D printing. Hydrogels such as oxidized alginate (ADA) and methacrylated gelatin (GelMA) were used as matrices. In the computational simulation, a combination of computational fluid dynamics and coarse-grained molecular dynamics was used to study the dynamics of rod-like fillers in the flow field of a syringe. It showed that, during the extrusion process, microrods are far from being well aligned. Instead, many of them tumble on their way through the needle leading to a random orientation in the fiber which was confirmed experimentally. Full article

Postoperative adhesion is a common post-surgery complication formed between the surface of the body cavity, ranging from a layer of connective tissue to a fibrous bridge containing blood vessels and nerve tissue. Despite achieving a lot of progress, the mechanisms of adhesion formation still need to be further studied. In addition, few current treatments are consistently effective in the prevention of postoperative adhesion. Hydrogel is a kind of water-expanding crosslinked hydrophilic polymer network generated by a simple reaction of one or more monomers. Due to the porous structure, hydrogels can load different drugs and control the drug release kinetics. Evidence from existing studies has confirmed the feasibility and superiority of using hydrogels to counter postoperative adhesions, primarily due to their outstanding antifouling ability. In this review, the current research status of hydrogels as anti-adhesion barriers is summarized, the character of hydrogels in the prevention of postoperative adhesion is briefly introduced, and future research directions are discussed. Full article

To maintain a healthy and functional status, equine hypsodont teeth have to produce lifelong large amounts of subocclusal dentin to prevent occlusal pulp exposure, which is caused by occlusal wear. To examine the cyto- and histological components that guarantee the lifelong high productivity of equine pulp, a limited number of ten incisors and ten cheek teeth from seven adult horses (aged 5 to 24 years) and five foals were sampled for preliminary histomorphometric and histomorphological evaluations. Independently of age, the equine dental pulp featured constant layers of predentin and odontoblastic cells, as well as soft connective tissue, composed of a cellular fibrous matrix, in which blood vessels and nerve fibers were embedded. As a result of the progressive deposition of newly formed dentin, the layer of dentin became thicker with age, and the size of the pulp chamber decreased. In contrast to the brachydont teeth, the morphological characteristics of the odontoblastic layer and the width of the predentin layer did not change with age. Therefore, it is assumed that the equine pulp tissue retained their juvenile status, which explains its unchanged ability to produce high amounts of subocclusal dentin. These preliminary, but clinically significant, findings are worthy of further investigation in order to identify strategies for equine-specific endodontic therapies. Full article

Peripheral nerve injury still remains a major clinical challenge, since the available solutions lead to dysfunctional nerve regeneration. Even though autologous nerve grafts are the gold standard, tissue engineered nerve guidance grafts are valid alternatives. Nerve growth factor (NGF) is the most potent neurotrophic factor. The development of a nerve guidance graft able to locally potentiate the interaction between injured neurons and autologous NGF would be a safer and more effective alternative to grafts that just release NGF. Herein, a biofunctional electrospun fibrous mesh (eFM) was developed through the selective retrieval of NGF from rat blood plasma. The neurite outgrowth induced by the eFM-NGF systems was assessed by culturing rat pheochromocytoma (PC12) cells for 7 days, without medium supplementation. The biological results showed that this NGF delivery system stimulates neuronal differentiation, enhancing the neurite growth more than the control condition. Full article