BACKGROUND: Modern trends in reconstructive surgery involve the use of free perforator flaps to reduce the donor site morbidity. The course of perforator vessels has a great anatomic variability and demands detailed knowledge of the anatomical relationships and the variability of the course of the perforators. The numerous modifications to perforator nomenclature proposed by various authors resulted in confusion rather than simplification. In our study, we focused on the hypothesis that a septocutaneous perforator traverses from the given source vessel to the deep fascia adherent to but not to within the septum itself. METHODS: Sixty-nine septocutaneous perforators from three different limb donor sites (lateral arm flap, anterolateral thigh flap, and radial forearm free flap) were collected from the gross pathology specimens of 14 fresh cadavers. The gross picture and the cross-sections with the histological cross-sections on different levels were examined to determine the position of the vessel to the septal tissue. RESULTS: Of the observed 69 septal perforators, 61 (88.5%) perforators were adherent to but not within the septum. The remaining eight (12.5%) perforators passed through the septum. All these eight perforators were found in multiple different cross-section levels (2 of 19 in lateral arm flap, 3 of 27 in anterolateral thigh flap, and 3 of 23 in radial forearm free flap). CONCLUSION: Although septocutaneous vessels appear identical macroscopically, microscopically two types of vessels with paraseptal and intraseptal pathways are observed. The majority of these vessels are merely adherent to the septum having a paraseptal pathway, while a minority are within the septum and are "true" septocutaneous perforators. It is advisable to dissect with a piece of the septum in order to avoid damage or injury to the perforator.
- MeSH
- lidé MeSH
- mrtvola MeSH
- perforátorový lalok * krevní zásobení MeSH
- předloktí krevní zásobení chirurgie MeSH
- stehno krevní zásobení MeSH
- volné tkáňové laloky * krevní zásobení MeSH
- zákroky plastické chirurgie * metody MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an RNA virus responsible for coronavirus disease 2019 (COVID-19). While SARS-CoV-2 primarily targets the lungs and airways, it can also infect other organs, including the central nervous system (CNS). The aim of this study was to investigate whether the choroid plexus could serve as a potential entry site for SARS-CoV-2 into the brain. Tissue samples from 24 deceased COVID-19-positive individuals were analyzed. Reverse transcription real-time PCR (RT-qPCR) was performed on selected brain regions, including the choroid plexus, to detect SARS-CoV-2 viral RNA. Additionally, immunofluorescence staining and confocal microscopy were used to detect and localize two characteristic proteins of SARS-CoV-2: the spike protein S1 and the nucleocapsid protein. RT-qPCR analysis confirmed the presence of SARS-CoV-2 viral RNA in the choroid plexus. Immunohistochemical staining revealed viral particles localized in the epithelial cells of the choroid plexus, with the spike protein S1 detected in the late endosomes. Our findings suggest that the blood-cerebrospinal fluid (B-CSF) barrier in the choroid plexus serves as a route of entry for SARS-CoV-2 into the CNS. This study contributes to the understanding of the mechanisms underlying CNS involvement in COVID-19 and highlights the importance of further research to explore potential therapeutic strategies targeting this entry pathway.
- MeSH
- COVID-19 * virologie MeSH
- dospělí MeSH
- fosfoproteiny * metabolismus MeSH
- glykoprotein S, koronavirus * genetika metabolismus MeSH
- hematoencefalická bariéra * virologie MeSH
- internalizace viru MeSH
- koronavirové nukleokapsidové proteiny MeSH
- lidé středního věku MeSH
- lidé MeSH
- plexus chorioideus * virologie MeSH
- RNA virová * genetika MeSH
- SARS-CoV-2 * fyziologie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
INTRODUCTION: Nerve grafting with the sural nerve is a standard treatment method for radial nerve injury that requires another incision at the lateral ankle distal from the injured upper limb. The aim of this study was to investigate the common trunk (CTCB) of the inferior lateral brachial cutaneous nerve (ILBCN) and posterior antebrachial cutaneous nerve (PACN) as a possible donor inside the lateral intermuscular septum. MATERIALS AND METHODS: The arms and legs of 8 formalin-embalmed cadaver specimens were studied. The radial nerve, common trunk of the ILBCN and PACN, and the sural nerve were identified and measured in length and diameter. For histological examination, nerve samples from 6 fresh cadavers were harvested and processed for further axonal counting. RESULTS: The average length of the CTCB was 114.92 ± 18.9 mm. To match the diameter of the radial nerve at its proximal third, 3 cables of CTCB graft were necessary, which corresponds to a defect length of 3.8 cm. At the level of the distal third, the number of grafts was reduced to 2 with a corresponding defect length of 5.7 cm. The radial nerve contained 15162 ± 318 axons, and the CTCB comprised 3959 ± 176 axons. To match the axon count of the recipient nerve, 4 grafts of CTCB were necessary, which corresponded to a defect length of 2.8 cm. CONCLUSION: CTCB is a consistent and easily dissected cutaneous nerve branch of the radial nerve that can be used for bridging small gaps after neuroma-in-continuity in radial nerve palsy.
- MeSH
- lidé středního věku MeSH
- lidé MeSH
- mrtvola MeSH
- nervový transfer * metody MeSH
- nervus radialis * chirurgie anatomie a histologie zranění MeSH
- nervus suralis * transplantace anatomie a histologie MeSH
- senioři MeSH
- zákroky plastické chirurgie * metody MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Donor nerve selection is a crucial factor in determining clinical outcomes of facial reanimation. Although dual innervation approaches using two neurotizers have shown promise, there is a lack of evidence-based comparison in the literature. Furthermore, no animal model of dual reinnervation has yet been published. This study aimed to establish such a model and verify its technical and anatomical feasibility by performing dual-innervated reanimation approaches in Wistar rats. METHODS: Fifteen Wistar rats were divided into four experimental groups and one control group. The sural nerve was exposed and used as a cross-face nerve graft (CFNG), which was then anastomosed to the contralateral buccal branch of the facial nerve through a subcutaneous tunnel on the forehead. The CFNG, the masseteric nerve (MN), and the recipient nerve were coapted in one or two stages. The length and width of the utilized structures were measured under an operating microscope. Return of whisker motion was visually confirmed. RESULTS: Nine out of the eleven rats that underwent surgery survived the procedure. Whisker motion was observed in all experimental animals, indicating successful reinnervation. The mean duration of the surgical procedures did not differ significantly between the experimental groups, ensuring similar conditions for all groups. CONCLUSIONS: Our experimental study confirmed that the proposed reanimation model in Wistar rats is anatomically and technically feasible, with a high success rate, and shows good prospects for future experiments.
- MeSH
- faciální paralýza * chirurgie MeSH
- krysa rodu rattus MeSH
- modely nemocí na zvířatech MeSH
- nervus facialis * chirurgie fyziologie MeSH
- nervus suralis chirurgie MeSH
- potkani Wistar MeSH
- regenerace nervu * fyziologie MeSH
- vibrissae fyziologie inervace MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Brain metastases (BMs) are the most common intracranial tumors in adults and occur 3-10 times more frequently than primary brain tumors. Despite intensive multimodal therapies, including resection, radiotherapy, and chemotherapy, BMs are associated with poor prognosis and remain challenging to treat. BMs predominantly originate from primary lung (20-56%), breast (5-20%), and melanoma (7-16%) tumors, although they can arise from other cancer types less frequently. The metastatic cascade is a multistep process involving local invasion, intravasation into the bloodstream or lymphatic system, extravasation into normal tissue, and colonization of the distal site. After reaching the brain, circulating tumor cells (CTCs) breach the blood-brain barrier (BBB).The selective permeability of the BBB poses a significant challenge for therapeutic compounds, limiting the treatment efficacy of BMs. Understanding the mechanisms of tumor cell interactions with the BBB is crucial for the development of effective treatments. This review provides an in-depth analysis of the brain barriers, including the BBB, blood-spinal cord barrier, blood-meningeal barrier, blood-arachnoid barrier, and blood-cerebrospinal fluid barrier. It explores the molecular and cellular components of these barriers and their roles in brain metastasis, highlighting the importance of this knowledge for identifying druggable targets to prevent or limit BM formation.
INTRODUCTION: The choroid plexus is located in the cerebral ventricles. It consists of a stromal core and a single layer of cuboidal epithelial cells that forms the blood-cerebrospinal barrier. The main function of the choroid plexus is to produce cerebrospinal fluid. Subarachnoid hemorrhage due to aneurysm rupture is a devastating type of hemorrhagic stroke. Following subarachnoid hemorrhage, blood and the blood degradation products that disperse into the cerebrospinal fluid come in direct contact with choroid plexus epithelial cells. The aim of the current study was to elucidate the pathophysiological cascades responsible for the inflammatory reaction that is seen in the choroid plexus following subarachnoid hemorrhage. METHODS: Subarachnoid hemorrhage was induced in rats by injecting non-heparinized autologous blood to the cisterna magna. Increased intracranial pressure following subarachnoid hemorrhage was modeled by using artificial cerebrospinal fluid instead of blood. Subarachnoid hemorrhage and artificial cerebrospinal fluid animals were left to survive for 1, 3, 7 and 14 days. Immunohistochemical staining of TLR4, TLR9, FPR2, CCL2, TNFα, IL-1β, CCR2 and CX3CR1 was performed on the cryostat sections of choroid plexus tissue. The level of TLR4, TLR9, FPR2, CCL2, TNFα, IL-1β was detected by measuring immunofluorescence intensity in randomly selected epithelial cells. The number of CCR2 and CX3CR1 positive cells per choroid plexus area was manually counted. Immunohistochemical changes were confirmed by Western blot analyses. RESULTS: Immunohistochemical methods and Western blot showed increased levels of TLR9 and a slight increase in TLR4 and FRP2 following both subarachnoid hemorrhage as well as the application of artificial cerebrospinal fluid over time, although the individual periods were different. The levels of TNFα and IL-1β increased, while CCL2 level decreased slightly. Accumulation of macrophages positive for CCR2 and CX3CR1 was found in all periods after subarachnoid hemorrhage as well as after the application of artificial cerebrospinal fluid. DISCUSSION: Our results suggest that the inflammation develops in the choroid plexus and blood-cerebrospinal fluid barrier in response to blood components as well as acutely increased intracranial pressure following subarachnoid hemorrhage. These pro-inflammatory changes include accumulation in the choroid plexus of pro-inflammatory cytokines, innate immune receptors, and monocyte-derived macrophages.
- Publikační typ
- časopisecké články MeSH
CXCL12 and CXCR4 proteins and mRNAs were monitored in the dorsal root ganglia (DRGs) of lumbar (L4-L5) and cervical (C7-C8) spinal segments of naïve rats, rats subjected to sham operation, and those undergoing unilateral complete sciatic nerve transection (CSNT) on post-operation day 7 (POD7). Immunohistochemical, Western blot, and RT-PCR analyses revealed bilaterally increased levels of CXCR4 protein and mRNA in both lumbar and cervical DRG neurons after CSNT. Similarly, CXCL12 protein levels increased, and CXCL12 mRNA was upregulated primarily in lumbar DRGs ipsilateral to the nerve lesion. Intrathecal application of the CXCR4 inhibitor AMD3100 following CSNT reduced CXCL12 and CXCR4 protein levels in cervical DRG neurons, as well as the length of afferent axons regenerated distal to the ulnar nerve crush. Furthermore, treatment with the CXCR4 inhibitor decreased levels of activated Signal Transducer and Activator of Transcription 3 (STAT3), a critical transforming factor in the neuronal regeneration program. Administration of IL-6 increased CXCR4 levels, whereas the JAK2-dependent STAT3 phosphorylation inhibitor (AG490) conversely decreased CXCR4 levels. This indicates a link between the CXCL12/CXCR4 signaling axis and IL-6-induced activation of STAT3 in the sciatic nerve injury-induced pro-regenerative state of cervical DRG neurons. The role of CXCR4 signaling in the axon-promoting state of DRG neurons was confirmed through in vitro cultivation of primary sensory neurons in a medium supplemented with CXCL12, with or without AMD3100. The potential involvement of conditioned cervical DRG neurons in the induction of neuropathic pain is discussed.
- MeSH
- benzylaminy MeSH
- chemokin CXCL12 * metabolismus MeSH
- cyklamy farmakologie MeSH
- heterocyklické sloučeniny farmakologie MeSH
- interleukin-6 metabolismus MeSH
- krysa rodu rattus MeSH
- nemoci sedacího nervu metabolismus MeSH
- nervové receptory * metabolismus MeSH
- nervus ischiadicus * zranění metabolismus MeSH
- potkani Sprague-Dawley MeSH
- receptory CXCR4 * metabolismus MeSH
- regenerace nervu * MeSH
- signální transdukce * MeSH
- spinální ganglia * metabolismus MeSH
- transkripční faktor STAT3 * metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
INTRODUCTION: Various analgesics are used to control intense headaches in patients following subarachnoid hemorrhage. In addition to pain control, it has been shown that some analgesics can affect various pathophysiological cascades. Therefore, we devised a study to assess whether the use of metamizole has a significant impact on the development of ischemic complications, hydrocephalus, and the overall outcome in patients following aneurysmal subarachnoid hemorrhage in the context of the other non-opioids and opioids effects. METHODS: In our retrospective, single-center cohort study, we enrolled 192 patients diagnosed with subarachnoid hemorrhage. We recorded their initial clinical status, comorbidities, and the daily dosage of analgesics over 14 days of hospitalization after the onset of subarachnoid hemorrhage. Using univariate and subsequent multivariate logistic regression analysis, we assessed the influence of various factors, including analgesics, on the development of delayed cerebral ischemia and hydrocephalus, as well as on 2-week and 6-month outcomes. RESULTS: Although the administration of non-opioids, in general, had no effect on the development of delayed cerebral ischemia or hydrocephalus, the use of metamizole as the main analgesic was associated with a significantly lower chance of poor outcome at both 2-weeks and 6-months, as well as the development of delayed cerebral ischemia. As opioids were indicated primarily for analgosedation in mechanically ventilated patients with poor clinical status, their usage was associated with a significantly higher chance of poor outcome, delayed cerebral ischemia, and hydrocephalus. CONCLUSION: Our results suggest that the prescription of metamizole may be associated with better outcomes and a lower chance of delayed cerebral ischemia development in patients after subarachnoid hemorrhage. Considering the retrospective nature of our study and the limited worldwide availability of metamizole due to its prohibition in some countries, our results do not demonstrate a clear benefit but rather justify the need for subsequent prospective studies.
- MeSH
- analgetika terapeutické užití aplikace a dávkování MeSH
- antiflogistika nesteroidní * terapeutické užití aplikace a dávkování MeSH
- dospělí MeSH
- hydrocefalus etiologie MeSH
- ischemie mozku farmakoterapie MeSH
- lidé středního věku MeSH
- lidé MeSH
- metamizol * terapeutické užití aplikace a dávkování MeSH
- retrospektivní studie MeSH
- senioři MeSH
- subarachnoidální krvácení * farmakoterapie komplikace MeSH
- výsledek terapie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Paclitaxel is a widely used chemotherapeutic agent for treating various solid tumors. However, resulting neuropathic pain, often a lifelong side effect of paclitaxel, can limit dosing and compromise optimal treatment. The choroid plexus, located in the brain ventricles, spreads peripheral inflammatory reactions into the brain. Our study is the first to analyze the effects of paclitaxel on inflammatory alterations in the choroid plexus. We hypothesized that the choroid plexus could respond directly to paclitaxel and simultaneously be indirectly altered via circulating damage-associated molecular patterns (DAMPs) produced by paclitaxel application. Using immunohistochemical and Western blot analysis, we examined the levels of toll-like receptor 9 (TLR9) and formyl peptide receptor 2 (FPR2), along with the pro-inflammatory cytokines interleukin 6 (IL6) and tumor necrosis factor α (TNFα) in choroid plexus epithelial cells of male Wistar rats following paclitaxel treatment. Moreover, we utilized an in vitro model of choroid plexus epithelial cells, the Z310 cells, to investigate the changes in these cells in response to paclitaxel and DAMPs (CpG ODN). Our results demonstrate that paclitaxel increases TLR9 and FPR2 levels in the choroid plexus while inducing IL6 and TNFα upregulation in both acute and chronic manners. In vitro experiments further revealed that paclitaxel directly interacts with epithelial cells of the choroid plexus, leading to increased levels of TLR9, FPR2, IL6, and TNFα. Additionally, treatment of cells with CpG ODN, an agonist of TLR9, elicited upregulation of IL6 and TNFα. Our findings determined that paclitaxel influences the choroid plexus through both direct and indirect mechanisms, resulting in inflammatory profile alterations. Given the pivotal role of the choroid plexus in brain homeostasis, a compromised choroid plexus following chemotherapy may facilitate the spread of peripheral inflammation into the brain, consequently exacerbating the development of neuropathic pain.
- Publikační typ
- časopisecké články MeSH
STATEMENT OF PROBLEM: Accurate implant placement is essential for the success of dental implants. This placement influences osseointegration and occlusal forces. The freehand technique, despite its cost-effectiveness and time efficiency, may result in significant angular deviations compared with guided implantation, but the effect of angular deviations on the stress-strain state of peri-implant bone is unclear. PURPOSE: The purpose of this finite element analysis (FEA) study was to examine the effects of angular deviations on stress-strain states in peri-implant bone. MATERIAL AND METHODS: Computational modeling was used to investigate 4 different configurations of dental implant positions, each with 3 angles of insertion. The model was developed using computed tomography images, and typical mastication forces were considered. Strains were analyzed using the mechanostat hypothesis. RESULTS: The location of the implant had a significant impact on bone strain intensity. An angular deviation of ±5 degrees from the planned inclination did not significantly affect cancellous bone strains, which primarily support the implant. However, it had a substantial effect on strains in the cortical bone near the implant. Such deviations also significantly influenced implant stresses, especially when the support from the cortical bone was uneven or poorly localized. CONCLUSIONS: In extreme situations, angular deviations can lead to overstraining the cortical bone, risking implant failure from unfavorable interaction with the implant. Accurate implant placement is essential to mitigate these risks.
