The impact of the COVID-19 pandemic on the number of brain tumor surgeries in Poland: A national database study.

BACKGROUND: The coronavirus disease (COVID-19) pandemic has greatly affected the treatment of most medical conditions. In particular, the treatment of seriously ill patients had to be adjusted due to the limited availability of in-hospital procedures. OBJECTIVES: The aim of this study was to evaluate the effects of COVID-19-related changes on neuro-oncological surgeries in the Polish medical system. MATERIAL AND METHODS: Data from the period of 2010-2020 were collected from National Health Insurance database for 2 diagnosis-related groups: A11 (complex intracranial procedures) and A12 (large intracranial procedures). The total number of procedures and diagnoses per year, trend changes and changes in procedures grouped by medical type were analyzed, including resections/biopsies, malignant/stable (nonmalignant) lesions, elective/acute procedures, and length of stay. RESULTS: Mean yearly numbers of 7177 (standard deviation (SD) = 760) procedures and 5934 (SD = 1185) diagnoses were recorded. Both numbers were growing up to 9.1% per year until 2018. From 2018, a 3.1% decrease in the number of procedures was observed, with a significantly larger decrease of 10.5% observed in 2020 (p < 0.001). The number of diagnoses decreased in 2019 by 2.7%, and by 9.2% in 2020 (p = 0.706), with a statistically significant change in the annual growth rate (p = 0.044). The number of resections decreased by 11.5% in 2020 (p = 0.204), with a significant change in the annual growth rate (p < 0.001). The number of biopsies decreased by 2.5% in 2020 (p = 0.018), with the annual decrement in 2019/2020 also being significant (p = 0.004). Decreases were observed in 2019 and 2020 for the number of malignant (0.5% and 6.3%, respectively) and nonmalignant (5.4% and 12.9%, respectively) tumors (p = 0.233 and p = 0.682 for absolute values, and p = 0.008 and p = 0.004 for the annual growth rates, respectively). The number of acute procedures in 2020 further decreased by 9.8% from 5.5% decrease in 2019 (p = 0.004), and the number of elective procedures decreased by 11.8% (p = 0.009). The annual growth rates for both acute and elective procedures were statistically significant (p < 0.001 and p < 0.001). CONCLUSIONS: The decrease in the number of neuro-oncological surgeries appeared to be much lower than the 20% decrease observed for general oncological surgeries in Poland during the COVID-19 pandemic. This seems to have resulted from postponing the treatment of less critical cases (i.e., nonmalignant and elective) and focusing on the treatment of the most precarious patients.

The Incidence and Risk Factors for Allogeneic Blood Transfusions in Pediatric Spine Surgery: National Data.

(1) Background: Pediatric spinal surgery is a blood-intensive procedure. In order to introduce a rational blood management program, identifying the risk factors for transfusions is mandatory. (2) Methods: Data from the national database covering the period from January 2015 to July 2017 were analyzed. The available data included the demographics, characteristics of the surgeries performed, length of stay, and in-house mortality. (3) Results: The total number of patients used for the analysis was 2302. The primary diagnosis was a spinal deformity (88.75%). Most fusions were long, with four levels or more (89.57%). A total of 938 patients received a transfusion; thus, the transfusion rate was 40.75%. The present study identified several risk factors; the most significant was a number of levels fused greater than 4 (RR 5.51; CI95% 3.72-8.15; p < 0.0001), followed by the deformity as the main diagnosis (RR 2.69; CI95% 1.98-3.65; p < 0.0001). These were the two most significant factors increasing the odds of a transfusion. Other factors associated with an increased risk of transfusion were elective surgery, the female sex, and an anterior approach. The mean length of stay in days was 11.42 (SD 9.93); this was greater in the transfused group (14.20 vs. 9.50; p < 0.0001). (4) Conclusions: The rate of transfusions in pediatric spinal surgery remains high. A new patient blood management program is necessary to improve this situation.

Risk Factors for Ischemic Stroke After Revascularization Surgery in Patients with Moyamoya Disease: An Age-Stratified Comparative Meta-Analysis.

BACKGROUND: Patients who undergo revascularization surgery for moyamoya disease may develop postoperative ischemic stroke (pIS). Several studies have sought to identify risk factors; however, the findings remain highly inconsistent. METHODS: PubMed, Scopus, and Web of Science were used to extract references. The first phase of screening required the studies to be in English, involve patients surgically treated for moyamoya disease, and report pIS. The second phase required the studies to provide ≥10 patients and include a control group. RESULTS: All 22 studies were rated as high quality. Univariate analysis identified pediatrics <3 years of age as a risk factor for pIS (odds ratio [OR], 7.60; P < 0.0001). Among adult patients only, diabetes (OR, 2.10; P = 0.005), a Suzuki grade greater than 3 (OR, 1.74; P = 0.005), mean intraoperative systolic blood pressure (OR, 1.04; P < 0.0001), mean intraoperative diastolic blood pressure (OR, 1.04; P = 0.002), and revascularization in the left hemisphere (OR, 2.09; P = 0.001) were risk factors. Among both age groups, preoperative ischemic stroke (OR, 2.59; P < 0.00001) was a risk factor for pIS. Additionally, perioperative antiplatelet drug administration was a protective factor for specifically acute postoperative white thrombus among adult patients (OR, 0.35; P = 0.002). CONCLUSIONS: In addition to the methods discussed that can mitigate the risk of pIS, the risk factors identified in our analysis may be of great value among surgeons for identifying high-risk patients in order to apply prophylactic measures, as well as scheduling longer and more frequent follow-up visits.

Evaluation of Movement Restriction of Spinal Orthoses Using Inertial Measurement Units.

Despite the frequent use of orthopedic braces or spine stabilizers in diseases such as kyphosis, lordosis, and scoliosis, as well as in the case of injuries and rehabilitation after surgeries, there is no clear evidence of their proper stabilization of the spine while carrying out daily activities. This study sought to assess the spine's mobility while wearing three different orthopedic braces while performing basic tasks. Ten healthy subjects were enrolled. Three Inertial Measurement Units (IMUs) were attached superficially along the spine at approximate levels: cervical (C7), between thoracic (T8) and lumbar (L3), and sacrum. The angle between sensors was monitored to provide data on the sagittal profile. In addition, the displacement of the spine's longitudinal axis was measured (rotation). There are three types of orthopedic braces: the semi-rigid Hohmann corset, the Jewett brace, and the Thoracolumbar Fixed Spinal Orthosis (TLSO). Four tasks were monitored: standing, sitting, walking, and picking up an item from the floor with one hand. All braces provided a similar level of stability in both the sagittal plane and rotational axis while lifting an object. On the other hand, while walking and sitting, the TLSO was the only orthosis providing a statistically significant rigidity in the sagittal plane. When performing a more voluntary task, the measured rigidity of softer braces was significantly increased when compared with more involuntary tasks. A certain degree of motion restriction with spinal orthoses may come from the feedback pressure, which stimulates paraspinal muscles to contract and thus increases the overall rigidity of the trunk.

The Increased Mortality Rate with Lower Incidence of Traumatic Brain Injury during the COVID-19 Pandemic: A National Study.

BACKGROUND: the COVID-19 pandemic with the following lockdown strategies have affected virtually all aspects of everyday life. Health services all over the world faced the crisis on an unprecedented scale, hampering timely care delivery. The present study was designed to assess the impact of the COVID-19 outbreak on the incidence and treatment of traumatic brain injuries in Poland. METHODS: the data on hospital admissions with traumatic brain injuries as the primary diagnosis were extracted from the National Health Fund of Poland. For the purpose of this study, the search was limited to four relevant diagnosis-related groups. The overall in-house mortality was calculated. RESULTS: there were 115,200 hospitalizations due to traumatic brain injury identified in the database. Overall, in comparison with the average of six prior years, in 2020 the volume of patients with traumatic brain injury dropped by 24.68% while the in-house mortality rate was increased by 26.75%. CONCLUSIONS: the COVID-19 pandemic with the resulting lockdown caused a radical reduction in human mobility. It had a profound impact on the incidence of traumatic brain injury, which dropped significantly. At the same time, the mortality rate increased drastically.

Acute Stroke Care during COVID-19: National Data.

(1) Background: The pandemic of COVID-19 and subsequent lockdown strategies had a profound impact on many aspects of everyday life. During this time the world faced the unprecedented crisis of healthcare disrupting timely care delivery. This study was designed to evaluate the impact of the pandemic on the acute treatment of stroke in Poland. (2) Methods: The national data on hospitalizations with stroke as a primary diagnosis were obtained from the National Health Fund of Poland. Poisson regression was used to determine the significance of the change in hospital admissions. The differences between proportions were analyzed using the "N-1" Chi-squared test. (3) Results: During the COVID-19 period, the number of hospitalizations dropped by 8.28% with a monthly nadir of 22.02 in April. On a monthly scale during 2020, the greatest decrease was 22.02%. The thrombolysis ratio was also affected, with the highest monthly drop of 15.51% in November. The overall number of in-hospital deaths did not change. (4) Conclusions: The pandemic caused a serious disruption of the acute care of stroke. There is no evidence that the quality of care was seriously compromised.

Microstructure and Mechanical Properties of PU/PLDL Sponges Intended for Grafting Injured Spinal Cord.

Highly porous, elastic, and degradable polyurethane and polyurethane/polylactide (PU/PLDL) sponges, in various shapes and sizes, with open interconnected pores, and porosity up to 90% have been manufactured. They have been intended for gap filling in the injured spinal cord. The porosity of the sponges depended on the content of polylactide, i.e., it decreased with the increase of polylactide content. The rise of polylactide content caused an increase of Young modulus and rigidity as well as a more complex morphology of the polyurethane/polylactide blends. The mechanical properties, in vitro toxicity, and degradation in artificial cerebrospinal fluid were tested. Sponges underwent continuous degradation with varying degradation rates depending on the polymer composition. In vitro cell studies with fibroblast cultures proved the biocompatibility of the polymers. Based on the obtained results, the designed PU/PLDL sponges appeared to be promising candidates for bridging gaps within injured spinal cord in further in vitro and in vivo studies.

The Impact of Oxidative Stress Factors on the Viability, Senescence, and Methylation Status of Olfactory Bulb-Derived Glial Cells Isolated from Human Cadaver Donors.

The olfactory bulb (OB) is a unique structure in the central nervous system that retains the ability to create new neuronal connections. Glial cells isolated from the OB have been recently considered as a novel and promising tool to establish an effective therapy for central nervous system injuries. Due to the hindered access to autologous tissue for cell isolation, an allogeneic source of tissues obtained postmortem has been proposed. In this study, we focused on the morphological and molecular characteristics of human OB-derived glial cells isolated postmortem, at different time points after a donor's death. We evaluated the proliferative activity of the isolated cells, and investigated the ultrastructure of the mitochondria, the accumulation of intracellular reactive oxygen species, and the activity of superoxide dismutase. The data obtained clearly indicate that the duration of ischemia is crucial for the viability/senescence rate of OB-derived glial cells. The OB can be isolated during autopsy and still stand as a source of viable glial cells, but ischemia duration is a major factor limiting its potential usefulness in therapies.

Lizard tail spinal cord: a new experimental model of spinal cord injury without limb paralysis.

Spinal cord injury (SCI) is a well-known devastating lesion that sadly is very resistant to all treatment attempts. This fact has stimulated the exploration of multiple regenerative strategies that are examined at both the basic and clinical level. For laboratory research, differentin vivomodels are used, but each has many important limitations. The main limitation of these models is the high level of animal suffering related to the inflicted neurologic injury. It has caused a growing tendency to limit the injury, but this, in turn, produces incomplete SCI models and uncertainties in the neuroregeneration interpretation. To overcome such limitations, a new experimental SCI model is proposed. Geckos have been extensively examined as a potential animal model of SCI. Their spinal cord extends into the tail and can be transected without causing the typical neurologic consequences observed in rat models. In this study, we compared the gecko tail SCI model with the rat model of thoracic SCI. Anatomic and histologic analyses showed comparability between the gecko and rat in diameter of spinal canal and spinal cord, as well as applicability of multiple staining techniques (hematoxylin and eosin, immunostaining, and scanning and transmission electron microscopy). We tested the suitability ofin vivostudy with 3 prototype implants for the reconstruction of SCI: a multichannel sponge, a multilaminar tube, and a gel cylinder. These were compared with a spinal cord excision (control). A 20-wk observation revealed no adverse effects of SCI on the animals' well-being. The animals were easily housed and observed. Histologic analysis showed growth of nervous tissue elements on implant surface and implant cellular colonization. The study showed that the gecko SCI model can be used as a primary model for the assessment of SCI treatment methods. It provides a platform for testing multiple solutions with limited animal suffering before performing tests on mammals. Detailed results of the experimental conditions and testing techniques are provided.-Szarek, D., Marycz, K., Lis, A., Zawada, Z., Tabakow, P., Laska, J., Jarmundowicz, W. Lizard tail spinal cord: a new experimental model of spinal cord injury without limb paralysis.

Polyurethane/Polylactide-Blend Films Doped with Zinc Ions for the Growth and Expansion of Human Olfactory Ensheathing Cells (OECs) and Adipose-Derived Mesenchymal Stromal Stem Cells (ASCs) for Regenerative Medicine Applications.

Polymeric biomaterials based on polyurethane and polylactide blends are promising candidates for regenerative medicine applications as biocompatible, bioresorbable carriers. In current research we showed that 80/20 polyurethane/polylactide blends (PU/PLDL) with confirmed biological properties in vitro may be further improved by the addition of ZnO nanoparticles for the delivery of bioactive zinc oxide for cells. The PU/PLDL blends were doped with different concentrations of ZnO (0.001%, 0.01%, 0.05%) and undertaken for in vitro biological evaluation using human adipose stromal stem cells (ASCs) and olfactory ensheathing cells (OECs). The addition of 0.001% of ZnO to the biomaterials positively influenced the morphology, proliferation, and phenotype of cells cultured on the scaffolds. Moreover, the analysis of oxidative stress markers revealed that 0.001% of ZnO added to the material decreased the stress level in both cell lines. In addition, the levels of neural-specific genes were upregulated in OECs when cultured on sample 0.001 ZnO, while the apoptosis-related genes were downregulated in OECs and ASCs in the same group. Therefore, we showed that PU/PLDL blends doped with 0.001% of ZnO exert beneficial influence on ASCs and OECs in vitro and they may be considered for future applications in the field of regenerative medicine.

Polyurethane/polylactide-based biomaterials combined with rat olfactory bulb-derived glial cells and adipose-derived mesenchymal stromal cells for neural regenerative medicine applications.

Research concerning the elaboration and application of biomaterial which may support the nerve tissue regeneration is currently one of the most promising directions. Biocompatible polymer devices are noteworthy group among the numerous types of potentially attractive biomaterials for regenerative medicine application. Polylactides and polyurethanes may be utilized for developing devices for supporting the nerve regeneration, like nerve guide conduits or bridges connecting the endings of broken nerve tracts. Moreover, the combination of these biomaterial devices with regenerative cell populations, like stem or precursor cells should significantly improve the final therapeutic effect. Therefore, the composition and structure of final device should support the proper adhesion and growth of cells destined for clinical application. In current research, the three polymer mats elaborated for connecting the broken nerve tracts, made from polylactide, polyurethane and their blend were evaluated both for physical properties and in vitro, using the olfactory-bulb glial cells and mesenchymal stem cells. The evaluation of Young's modulus, wettability and roughness of obtained materials showed the differences between analyzed samples. The analysis of cell adhesion, proliferation and morphology showed that the polyurethane-polylactide blend was the most neutral for cells in culture, while in the pure polymer samples there were significant alterations observed. Our results indicated that polyurethane-polylactide blend is an optimal composition for culturing and delivery of glial and mesenchymal stem cells.

Influence of modified alginate hydrogels on mesenchymal stem cells and olfactory bulb-derived glial cells cultures.

BACKGROUND: Great potential of cellular therapies has generated extensive research in the field of cells harvesting and culturing. Transplantation of cell cultures has been used in a variety of therapeutic programs but in many cases it appeared that biomaterial scaffold or sheath would enhance cells regenerative potential. OBJECTIVE: Hydrogels composed of different proportions sodium and calcium alginates, were undertaken to evaluate their influence on mesenchymal stem cells and olfactory bulb-derived glial cells cultures. Additionally, these biomaterials were also enriched with fibrin protein. METHODS: The structure of materials was visualized by means of scanning electron microscopy. After seeding with cells - hydrogels were observed with inverted and fluorescence microscope. Cell's morphology, behavior and phenotype were analyzed in investigated materials by means of light, fluorescence and scanning electron microscopes. Also, viability assay was performed with Alamar Blue cytotoxic test. RESULTS: Our observations showed that basic alginate hydrogels had significant influence on both cell types. Materials maintained cells alive, which is desired attribute, however none of them kept cells in normal, flat form. Alginates with significant calcium component kept cells alive for longer period of culture. CONCLUSIONS: Addition of fibrin protein resulted in material's biocompatibility properties improvement, by creation of adhesion surface, which helps cells to keep proper morphology and behavior. Our findings suggest that addition of fibrin protein to alginate hydrogels improves them as cell carriers for regenerative medicine applications.

[Biomaterials engineering strategies for spinal cord regeneration: state of the art]. / Strategie inzynierii biomaterialów dla regeneracji rdzenia kregowego: aktualny stan wiedzy.

Traumatic spinal cord injuries are very serious burden for the organism of affected human population, and are more critical because mostly touching the young cluster of population. Physical, emotional and economic problems caused by traumatic spinal cord injuries as a general rule significantly limit the individual patient functionality and are burden for the society. The spinal cord has considerable lack of ability for spontaneous and functional regeneration, hence the spinal cord injury cause a solemn and frequently permanent disabilities. The pathophysiology of spinal cord injury is the results of sequential two phenomena, primary physical and biochemical secondary mechanisms of injury. After physical injury, the spinal cord undergoes a sequential progression in biochemical pathologic deviations increasing after injury, that are mutually deteriorating and cause further damage in the spinal cord. Consequently series of pathological processes lead to haemorrhage, oedema, neuronal necrosis, axonal fragmentation, demyelination of the remaining axons, and formation of ultimately cyst. Furthermore spinal cord injuries can immediately result in neural cells death and cause disruption of the blood supply to the site of the injury. The most important difference between peripheral and central nervous system is the fact that in the spinal cord the neuronal cell bodies are damaged, while in the peripheral nervous system only axons are injured. In the surroundings of the spinal cord, one of the major factors hampering regeneration is the glial scar expansion. The spreading of densely packed astrocytes on the site of injuries effectively inhibit axon growth through the nerve grow blocking. Glial scar, which consists mainly of overactive astrocytes and fibroblasts, as well as the presence of growth-inhibitor molecules such as chondroitin sulphate proteoglycans (derived from the breakdown of damaged nerve cells) form a physicochemical barrier for effective regenerating axons. The recent scientific progress in medicine, biology and biomaterials engineering, and predominantly in the fields of neurosurgery, cell culture and tissue engineering, creates the opportunity for the development of new therapies, which support healing of the effects of traumatic spinal cord injuries and prevent further neurodegenerative processes. The most promising effects so far have been obtained using well-designed polymer scaffold as structural support for axon regeneration combined with drug delivery system or therapeutic cell line and neurotrophic factors. This review article focuses on the application of selected biomaterials for the regeneration of traumatic spinal cord injuries. First, the basic anatomical structure of the spinal cord has been described. Then the injury and neurodegenerative mechanisms within the peripheral and central nervous system have been compared. The pathophysiology of the spinal cord damage has been referred to the current strategy of biomaterials engineering in experimental therapies supporting neuroregeneration processes. In the summary, the promising interdisciplinary therapeutic strategies aimed at the regeneration of the spinal cord have been highlighted.

Transplantation of autologous olfactory ensheathing cells in complete human spinal cord injury.

Numerous studies in animals have shown the unique property of olfactory ensheathing cells to stimulate regeneration of lesioned axons in the spinal cord. In a Phase I clinical trial, we assessed the safety and feasibility of transplantation of autologous mucosal olfactory ensheathing cells and olfactory nerve fibroblasts in patients with complete spinal cord injury. Six patients with chronic thoracic paraplegia (American Spinal Injury Association class A-ASIA A) were enrolled for the study. Three patients were operated, and three served as a control group. The trial protocol consisted of pre- and postoperative neurorehabilitation, olfactory mucosal biopsy, culture of olfactory ensheathing cells, and intraspinal cell grafting. Patient's clinical state was evaluated by clinical, neurophysiological, and radiological tests. There were no adverse findings related to olfactory mucosa biopsy or transplantation of olfactory ensheathing cells at 1 year after surgery. There was no evidence of neurological deterioration, neuropathic pain, neuroinfection, or tumorigenesis. In one cell-grafted patient, an asymptomatic syringomyelia was observed. Neurological improvement was observed only in transplant recipients. The first two operated patients improved from ASIA A to ASIA C and ASIA B. Diffusion tensor imaging showed restitution of continuity of some white matter tracts throughout the focus of spinal cord injury in these patients. The third operated patient, although remaining ASIA A, showed improved motor and sensory function of the first spinal cords segments below the level of injury. Neurophysiological examinations showed improvement in spinal cord transmission and activity of lower extremity muscles in surgically treated patients but not in patients receiving only neurorehabilitation. Observations at 1 year indicate that the obtaining, culture, and intraspinal transplantation of autologous olfactory ensheathing cells were safe and feasible. The significance of the neurological improvement in the transplant recipients and the extent to which the cell transplants contributed to it will require larger numbers of patients.

Morphological characterization of gecko's (eublepharis macularius) glial cells in culture / Caracterización morfológica de las células gliales del gecko (eublepharis macularius) en cultivo

Central nervous system of reptiles has the ability to grow and regenerate during adult life of the animal. Therefore, cells creating CNS of this animal class should compound substances or molecules enabling neuroregeneration. Cells directly involved in this process have not been clearly characterized, especially in cell culture environment. Morphology of reptilian glial adherent cells should be known better to find any differences from mammalian CNS cells. We isolated glial cells from olfactory bulb and cerebrum from gecko (Eublepharis macularius) and cultured separately. We have observed populations of cells with proliferative capacity in both types of cultures. Also, we have detected lipid molecules deposits within their cytoplasm, which localization was correlated with mitochondria position. This information can be helpful in searching new bioactive substances involved in regeneration of central nervous system.

El sistema nervioso central de los reptiles tiene la capacidad de crecer y regenerarse durante la vida adulta del animal. Por lo tanto, las células de SNC creadas de esta clase de animales deberían componerse de sustancias o moléculas que permiten la neuroregeneración. Las células que participan directamente en este proceso no han sido claramente caracterizadas, especialmente en el entorno de cultivo celular. La morfología de las células adherentes gliales de reptiles deben ser reconocidas y diferenciarse respecto a las células del SNC de mamíferos. Se aislaron células gliales del bulbo olfatorio y el cerebro del Gecko (Eublepharis macularius) y se cultivaron por separado. Se observaron poblaciones de células con capacidad proliferativa en ambos tipos de cultivos. Además, se detectaron moléculas de depósitos lipídicos dentro de su citoplasma, y su localización se correlacionó con la posición de las mitocondrias. Esta información puede ser útil en la búsqueda de nuevas sustancias bioactivas que participan en la regeneración del sistema nervioso central.

Influence of calcium alginate on peripheral nerve regeneration: in vivo study.

Recently, we described the influence of sodium alginate on the inflammatory infiltrate during neuroregeneration in tube nerve grafts. It was noticeable that there was the coexistence of inflammatory cells, including neutrophils, plasma cells, and macrophages with Schwann cells and axons. This may indicate a beneficial interaction between alginates and the infiltrate and the additional beneficial effect of the cells on the neuroregeneration process in the inflammatory infiltrates. In this study, we have performed in vivo evaluation of our novel tubular implant prepared by a polyurethane/polylactide blend filled with alginate fibers. The influence of filling the lumen of the tubes with sodium and calcium alginates on the regeneration process of the rat sciatic nerve was investigated. The neuroregeneration process was assessed by detailed histomorphometric studies, axon counting, and calculating the regenerative indexes. It was observed that calcium alginate had a supportive effect on nerve regeneration similar to nerve autotransplant.

Assessment of in vivo behavior of polymer tube nerve grafts simultaneously with the peripheral nerve regeneration process using scanning electron microscopy technique.

In this study, scanning electron microscopy (SEM) has been applied for instantaneous assessment of processes occurring at the site of regenerating nerve. The technique proved to be especially useful when an artificial implant should have been observed but have not yet been extensively investigated before for assessment of nerve tissue. For in vivo studies, evaluation of implant's morphology and its neuroregenerative properties is of great importance when new prototype is developed. However, the usually applied histological techniques require separate and differently prepared samples, and therefore, the results are never a 100% comparable. In our research, we found SEM as a technique providing detailed data both on an implant behavior and the nerve regeneration process inside the implant. Observations were carried out during 12-week period on rat sciatic nerve injury model reconstructed with nerve autografts and different tube nerve grafts. Samples were analyzed with haematoxylin-eosin (HE), immunocytochemical staining for neurofillament and S-100 protein, SEM, TEM, and the results were compared. SEM studies enabled to obtain characteristic pictures of the regeneration process similarly to TEM and histological studies. Schwann cell transformation and communication as well as axonal outgrowth were identified, newly created and matured axons could be recognized. Concurrent analysis of biomaterial changes in the implant (degradation, collapsing of the tube wall, migration of alginate gel) was possible. This study provides the groundwork for further use of the described technique in the nerve regeneration studies.

[The outlook for the use of polymeric scaffolds in the reconstruction and the regeneration stimulation of traumatic brain injuries]. / Perspektywy wykorzystania polimerowych rusztowan w rekonstrukcji oraz stymulacji regeneracji pourazowych uszkodzen mózgu.

Neurological disorders and injuries such as ischemic or haemorrhagic strokes or traumatic brain injuries result in the damage of cerebral parenchyma structures and in consequence, the loss of neurological functions. The current clinical strategies for the treatment of the brain nervous tissue disruptions are limited. The aforementioned methods can reduce the tissue degeneration or mitigate the subsequent symptoms, but do not alter the fact that many of the affected people are incapable of returning to the condition before the accident and they need long-lasting rehabilitation. Regenerative strategies based on the cell therapies and the use of polymeric scaffolds seem to be very promising for many patients. Polymer scaffolds may provide an opportunity to enhance the probability of cell therapy success by creating an artificial extracellular matrix which further facilitates cell survival, proliferation, differentiation, and promotes integrity of transplanted as well as endogenous cells. This paper presents selected forms of the polymeric scaffolds, which have been tested for the restoration processes within brain tissue and their potential clinical applications of scaffolds in both the treatment of posttraumatic neuronal loss and the neurodegenerative disorders.

Bilateral chronic subdural haematomas in a patient with meningioma of the superior sagittal sinus - case report and pathophysiological study.

Bilateral chronic subdural haemorrhage accompanying meningioma is a very rare clinical condition. We present a case of a 69-year-old female patient with large meningioma completely obliterating the posterior third part of the superior sagittal sinus with accompanying bilateral chronic subdural haematomas. Three anatomical zones of venous collateral circulation were revealed by the preoperative digital subtraction angiography. The tumour and haematomas were removed completely with no major complications. The most likely pathomechanism of the development of bilateral chronic subdural haematomas was venous hypertension caused by an occlusion of major cerebral venous trunks. As a result of a minor thrombotic incident or insignificant head injury, the distended veins of collateral circulation that were volumetrically burdened could have been damaged. Patients with large tumours occluding the superior sagittal sinus, who did not qualify for or refused surgery, should be carefully monitored clinically and neuroradiologically because of possibly increased risk of an intracranial haemorrhage.