Fibrous Ring Research Articles

Biomechanics of the intervertebral disc : Consequences of degenerative changes

The intervertebral disc represents the flexible connection between two adjacent vertebral bodies. Intervertebral discs, therefore, give the spine its enormous range of motion. At the same time, intervertebral discs distribute the load evenly over the bony vertebral bodies to ensure load transfer from the upper body to the pelvis, provide sufficient stability, and absorb shocks during everyday movements as well as under extreme loads. The two tissue regions of the intervertebral disc, the central fluid-rich core (nucleus pulposus) and the lamellae of the outer fibrous ring (annulus fibrosus) experience different stresses under load and movement. This article summarizes current knowledge on the biomechanical properties of the intervertebral disc and explains how these are altered by degeneration and which surgical treatment options for degenerated and herniated discs are advisable from abiomechanical perspective.

Analysis of Echocardiography Indicators Depending on the Type of Surgical Correction of the Mitral Valve in Patients with Ischemic Heart Disease

The aim. To study the influence of echocardiography indicators on the choice of surgical intervention on the mitral valve in patients with mitral insufficiency and coronary heart disease. Materials and methods. The study included patients with mitral insufficiency who underwent myocardial revascularization and mitral valve reconstruction (plasty or replacement). The mean age of the study participants was 65.9 ± 4.0 years. The material for analysis was data from the primary medical records: medical history, clinical and instrumental examination data and protocols of operations. The division into study groups was performed retrospectively, according to the mitral valve operation performed: plasty (experimental group) or replacement (control group). Results. We identified the features of the main echocardiographic data that guide the cardiologist when choosing the tactics of surgical correction of the mitral valve. It was established that in patients of the research group, the following was reliably significant: moderate degree of mitral insufficiency (p = 0.02; χ2 = 9.38), decrease in the systolic function of the left ventricle (p = 0.001; χ2 = 10.75); it was found that calcium deposits on the fibrous ring of the mitral valve were insignificant. When analyzing the morphological changes in patients of the experimental group, we found a significantly lower frequency of anterior leaflet prolapse (p = 0.04; χ2 = 4.21) and in general the frequency of all prolapses of any type, while in the control group the frequency of all prolapses was significantly higher (p = 0.04; χ2 = 4.0). In patients of the control group, a significantly higher frequency of akinesis (p = 0.04; χ2 = 4.21) and hypokinesis zones of the posterior-inferior-lateral wall (p = 0.001; χ2 = 19.76) was established, which is an additional sign of involvement of the chordal-muscular apparatus of the mitral valve in pathological process. Conclusions. As a result of the study, echocardiographic differences in the structure of the mitral valve were established, which influenced the selection of the intervention volume. It was found that in patients of the experimental group, the early postoperative mortality and the duration of inpatient treatment were significantly higher than in patients of the control group, which indicates the imperfection of the criteria used by cardiac surgeons when choosing the tactics of surgical correction of the mitral valve in an attempt to perform organ-preserving surgery.

Results of surgical treatment of aortic stenosis in patients with a narrow aortic root after Ozaki surgery and bioprosthetics: A retrospective single-center study

BACKGROUND: Aortic stenosis (AS) itself is a common disease in patients of older populations, and its combination with a narrow aortic root puts the surgeon in front of choosing the most optimal option. The advantages of Ozaki's operation include hemodynamics close to the native aortic valve (AV) and the absence of the need for lifelong anticoagulant therapy. AIM: To evaluate the hospital and long-term results of surgical treatment of patients with AS and a narrow fibrous ring who underwent Ozaki surgery or AV prosthetics with a biological prosthesis. MATERIALS AND METHODS: In total, 836 isolated Ozaki operations or combined interventions of this kind were performed at the Federal Center for Cardiovascular Surgery (Penza). This retrospective single-center study included 150 patients with critical AC (effective opening area ≤1 cm2) in whose surgical treatment tactics Ozaki surgery or prosthetics with a biological prosthesis were used. RESULTS: In the early postoperative period, group 1 patients had significantly lower values of the average and maximum gradients on the aortic valve and a larger area of the effective opening of the aortic valve. Also, in group 1 patients, the postoperative period of stay in intensive care is significantly higher, which is a consequence of the longer duration of the operation, the time of artificial circulation and myocardial ischemia. Long-term mortality is higher in the group with prosthetics of AV (Log Rank=0.006). Freedom from re-operation according to the analysis, there was no significant difference between the groups (Log Rank=0.226). CONCLUSION: Ozaki surgery demonstrates the best hemodynamic characteristics on AV in comparison with a biological prosthesis in patients with a narrow fibrous ring of AV in the early and long-term follow-up periods.

Comparison of foci of active inflammation and fatty degeneration according to MRI and CT data of syndesmophytes in patients with ankylosing spondylitis

Introduction. Syndesmophyte, which is the hallmark of ankylosing spondylitis (AS), is a vertically oriented ossification located outside the fibrous ring of the intervertebral disc. In recent decades, the most widespread theory is that after inflammation in the area of attachment of the fibrous ring to the vertebral body, fatty degeneration occurs with reparative processes, as a result of which the growth of new bone – syndesmophyte – begins. It is believed that the likelihood of developing syndesmophyte is two to three times higher in the angles of those vertebrae in which active inflammation or fatty changes were detected on magnetic resonance tomography (MRI) in the previous 2 years, the latter having a stronger association with subsequent pathological bone formation. However, this relationship is ambiguous according to different studies.The aim – comparison of the exact localization of magnetic resonance tomography and computed tomography (CT) signs of lesions on the vertebral endplates, characteristic of axial spondyloarthritis, in patients with ankylosing spondylitis.Material and methods. The cross-sectional study included 10 patients with AS who met the inclusion criteria.All patients underwent a standard examination for AS, as well as MRI and CT examination of the lumbar spine.A special technique for joint assessment of changes detected during MRI and CT examination has been developed.For the primary analysis, changes found on the upper endplates of 5 lumbar vertebrae were taken.Results. On the upper endplates of 5 lumbar vertebrae, a CT examination revealed 35 syndesmophytes (from 1 to 7 syndesmophytes in 1 patient), and MRI revealed 9 foci of acute inflammation and 24 of chronic inflammation (fatty degeneration). When jointly analyzing the MRI foci of detectable inflammation and syndesmophytes transferred to the vertebral diagram, it turned out that in the majority of cases (68%), the latter were not associated with sites of active and/or chronic inflammation. Correlation analysis showed a certain direct relationship only between the number of syndesmophytes and foci of chronic inflammation (r=0.68).Discussion. Preliminary data show that the proposed method for comparing MRI and CT lesions in AS allows us to jointly study the localization of MRI and CT spinal injuries in patients with AS using multidirectional sections. The first results of our one-time study showed that in most cases the localization of developing syndesmophytes does not coincide with the foci of inflammation detected by MRI (both acute and chronic).

498. LATROGENIC ESOPHAGEAL DISEASE POST OBESITY TREATMENT: SEVERE ESOPHAGEAL DILATATION RELATED TO ADJUSTABLE GASTRIC BANDING (AGB)

Abstract Iatrogenic Esophageal Disease post obesity treatment: severe esophageal dilatation related to adjustable gastric banding (AGB) Introduction Obesity is considered one of the biggest epidemics of the 21st century, which pushes us as health professionals to seek for solutions to this pathology. Within the medical-surgical approach, the most used techniques are gastric bypass, vertical gastrectomy and adjustable gastric banding (AGB). Even though they are frequently used, they are not free of complications. In this communication based on a case we would like to comment on the main complications of the use of the gastric band. These side effects has being between 0.5-5% to 20%: stoma stenosis, band slippage, intraluminal erosion, gastric volvulus and perforation. Clinical Case 54-year-old woman underwent surgery 20 years ago for obesity using a restrictive technique with adjustable gastric banding. The patient began 18 years later with retrosternal pain, epigastric pain, vomiting and dysphagia. Endoscopic tests revealed esophageal dilation with retention of food remains, tortuous and macerated mucosa; said achalasia was caused by a gastroesophageal stenosis. Among the diagnostic tests, an esophageal-gastric-duodenal barium transit was performed, showing a decrease in peristalsis with diffuse esophageal dilation of up to 7cm in diameter. Stenosis was observed in the lower esophageal third at the level of the esophagogastric junction of approximately 16 x 11 mm in longitudinal and transverse diameters. Evolution Surgical removal of the device is decided by a multidisciplinary team. Laparoscopic release of the gastric band was performed with electrocautery following adhesions around the device. Complete withdrawal upon release. Intraoperative endoscopy was performed, showing significant esophageal dilation with retained fermented food remains, mucous membrane affected by esophageal candidiasis. After the esophagogastric junction, a gastric fibrous ring was evidenced at the place of location of the gastric band, with good passage without evidence of gastric or esophageal lesions. Favorable postoperative evolution, being discharged 24 hours after surgery. After the case we observed the failure of the safety mechanism of the gastric band that regulates the internal diameter of the device due to the formation of a fibrotic constriction ring. Removal of the device improves the symptoms without requiring, in this case, section of the constriction ring. Currently, the patient shows improvement in her symptoms 6 months after the bariatric revision surgery.

Polymorphisms of the collagen genes of the fibrous ring rs1800012, rs2276454, rs1793953, and the VDR gene rs2228570 with intervertebral disc degeneration

Background. Spinal diseases cause significant disability, with genetic factors influencing up to 70 % of cases. This study purposed to examine the association of polymorphisms of COL1A1rs1800012, COL2A1rs2276454, COL2A1rs1793953 (collagen genes), and VDRrs2228570 with L4-L5, L5-S1, C5-C7 with intervertebral disc degeneration among ethnic Ukrainians. Materials and methods. The study included 90 individuals with L5-S1 disc degeneration, 50 — with L4-L5 degeneration, 30 — with C5-C7, and 66 controls without disc degeneration. Applied Biosystems (USA) kits were used for genotyping. Statistical analysis was performed using SNPStats. Results. There was an association between the C/C genotype and L5-S1 disc degeneration in men (odd ratio (OR) was 2.255, 95% confidence interval (CI): 1.089–4.670; χ2 = 4.905; p = 0.027), whereas the C/T genotype may have a protective effect (OR = 0.418, 95% CІ: 0.217–0.802; χ2 = 6.689, p = 0.009). The C/T genotype may also have protective significance for C5-C7 disc degeneration in men: its occurrence was higher among men in the control group compared to women (OR = 3.85, 95% CІ: 1.086–13.648; χ2 = 4.67; p = 0.031). The G/A COL2A1rs2276454 variant may have a protective effect on the L5-S1 disc (OR = 3.50, 95% CІ: 1.26–9.72; χ2 = 6.02; p = 0.015). The pair of alleles COL2A1rs2276454/COL2A1rs1793953 were linked to degenerative changes of the L4-L5 disc in the case group (p = 0.001); COL1A1rs1800012/VDRrs2228570 and COL2A1rs1793953/VDRrs2228570 were linked to degenerative changes in the C5-C7 disc. Conclusions. The C/C VDRrs2228570 genotype in men was associated with L5-S1 intervertebral disc degeneration. The T/C VDRrs2228570 genotype may have a protective significance for men with L5-S1 and C5-C7 degeneration. The COL2A1rs2276454 variant may have a protective effect against the development of L5-S1 degenerative changes in men. The allele pairs COL1A1rs1800012/VDRrs2228570, COL2A1rs1793953/VDRrs2228570, and COL2A1rs2276454/COL2A1rs1793953 were associated with C5-C7 degeneration, while the COL2A1rs2276454/COL2A1rs1793953 pair were associated with L4-L5 degeneration.

Oxidative stress-induced EGR1 upregulation promotes NR4A3-mediated nucleus pulposus cells apoptosis in intervertebral disc degeneration.

This study aimed to reveal the specific role of early growth response protein 1 (EGR1) and nuclear receptor 4A3 (NR4A3) in nucleus pulposus cells (NPCs) and the related molecular mechanism and to identify a new strategy for treating intervertebral disc degeneration (IVDD). Bioinformatics analysis was used to explore and predict IVDD-related differentially expressed genes, and chromatin immunoprecipitation sequencing (ChIP-seq) revealed NR4A3 as the EGR1 target gene. An in vitro NPC model induced by tributyl hydrogen peroxide (TBHP) and a rat model induced by fibrous ring acupuncture were established. Western blotting, quantitative real-time polymerase chain reaction (qRT-PCR), immunohistochemical staining, immunofluorescence staining, and flow cytometry were used to detect the effects of EGR1 and NR4A3 knockdown and overexpression on NPC apoptosis and the expression of extracellular matrix (ECM) anabolism-related proteins. Interactions between EGR1 and NR4A3 were analyzed via ChIP-qPCR and dual luciferase assays. EGR1 and NR4A3 expression levels were significantly higher in severely degenerated discs (SDD) than in mildly degenerated discs (MDD), indicating that these genes are important risk factors in IVDD progression. ChIP-seq and RNA-seq revealed NR4A3 as a direct downstream target of EGR1, and this finding was verified by ChIP-qPCR and dual luciferase reporter experiments. Remarkably, the rescue experiments showed that EGR1 promotes TBHP-induced NPC apoptosis and impairs ECM anabolism, dependent on elevated NR4A3 expression. In summary, the EGR1-NR4A3 axis mediates the progression of NPC apoptosis and ECM impairment and is a potential therapeutic target in IVDD.

Modern views on the pathogenesis of intervertebral disc degeneration

Introduction. Intervertebral disc (IVD) degeneration is defined as a multifactorial degenerative disease of the spine, starting from the structures of the nucleus pulposus of the IVD, spreading to the fibrous ring and other elements of the spinal motion segment. Unlike natural aging, a pathological degenerative process that occurs in IVDs as a result of the additive effect of genetic predisposition and external environmental factors leads to the formation of chronic back pain and reduces the patient’s quality of life. Despite many years of studying the problem of the pathogenesis of IVD degeneration, it is far from being resolved, which encourages us to further study the pathogenetic mechanisms of the development of this pathology.Aim. To update the knowledge of practicing neurologists about the results of modern studies of the leading mechanisms of development of IVD degeneration in humans and their role in the development of promising biomarkers of this pathology and new strategies for pathogenetic therapy.Materials and methods. A search and analysis of publications was carried out in Russian-language (e-Library) and Englishlanguage databases (PubMed, Oxford Press, Clinical Keys, Springer, Elsevier, Google Scholar). Search depth – 5 years (2018–2023).Results. The analyzed and generalized results of studies of the molecular mechanisms influencing the development and progression of this pathology are presented. The leading pathogenetic mechanisms for the development of IVD degeneration, such as oxidative stress and the NO system, cytokine imbalance, increased activity of matrix metalloproteinases, dysfunction of fibrillar collagens and proteoglycan, as well as their relationship with each other, were considered.Conclusion. The review provides a broader look at the pathogenetic mechanisms of IVD degeneration, which makes it possible to set new goals for future development of promising therapeutic strategies.

Morphometric evaluation of the left atrioventricular valve complex and its clinical relations.

In this study, it was aimed to evaluate morphometrically and morphologically the left fibrous ring, mitral leaflets, tendinous cords, and papillary muscles, which are the components of the left atrioventricular valve complex (LAVC), and to reveal their clinical relationships. A total of 120 human hearts were examined at the Forensic Medicine Institute. Cases aged 30 years and older, less than 24 hours after their death, were included in the study. Heart length, width, height/width ratio, anteroposterior and mediolateral diameters of the annulus, annular area, length and width of leaflets, number and attachment sites of tendinous cords, number, shape, length, the width of papillary muscles, and distances to various points were recorded to determine their spatial configurations. As well as the measurement data of LAVC components in cases with and without cardiovascular disease (CVD), the relationships of these data with the demographic characteristics of the cases are also explained. In the diagnostic performance test (ROC analysis), it was determined that body mass index (> 26.7), heart weight (> 414 g), heart height/width ratio (≤ 1.24), mitral valve width (> 99.96 mm), left ventricular wall thickness (> 15.08 mm), annular area (> 619.37 mm²) and mediolateral diameter of the annulus (> 30.71 mm) are important diagnostic criteria in determining CVD if they are outside the specified reference values. This study provides anatomical information about LAVC, as well as recommendations for diagnosis and surgical treatment planning. We therefore believe that our findings will be useful to clinicians.

Influence of dapagliflozin on cardiovascular remodeling in hypertensive patients with accompanying type 2 diabetes

Aim. To compare the results of 12-week treatment of patients with stage II hypertension (HTN) with accompanying diabetes mellitus (DM) type 2 between the combination of metformin + dapagliflozin and metformin monotherapy by studying changes in the elastic properties of the common carotid arteries (CCA), echocardiographic indicators, 24-hour ambulatory blood pressure monitoring (ABPM) and laboratory parameters of lipid and carbohydrate metabolism. Materials and methods. 24 patients with stage II HTN with type 2 DM were involved in the study, the average age was 60.4 years, 50 % – men. Patients in the first group were randomized to receive metformin, and the second group – to receive a combination of metformin and dapagliflozin. At inclusion and after 3 months of treatment, basic anthropometric data, laboratory indicators of lipid and carbohydrate metabolism, ABPM, echocardiography, and indicators of CCA local stiffness were studied. Statistical analysis was performed, the probability of differences is at the level of p < 0.05. Results. In both observation groups, there was a comparable decrease in SCORE 2-Diabetes range, glucose and glycated hemoglobin, total cholesterol, LDL cholesterol, average daily systolic blood pressure (SBP), daily SBP load, day and night pulse BP, as well as an increase in speed systolic movement of the lateral fibrous ring of the mitral valve (S lat). Only in the metformin + dapagliflozin group a decrease in the adipose tissue level, the average daily diastolic blood pressure (DBP), the burden of DBP, the size of the left atrium and right ventricle, an increase in the movement speeds of the medial (e’med), lateral (e’lat) ring of the mitral and of the tricuspid (e’tk) valve in the period of early diastolic filling of the ventricles, velocities of systolic movement of the medial fibrous ring of the mitral (S med) and tricuspid (S tk) valves, a decrease in the ratio E/e’, and an improvement in the elastic properties of general carotid arteries were observed. Conclusions. In persons with HTN stage II with DM type 2 the addition of dapagliflozin to the treatment regimen was associated with better control of blood pressure, improvement of diastolic function and longitudinal contractility of the left ventricle, elastic properties of CCA.

Dynamics of structural transformations of intervertebral discs in humans in the fetal period

BACKGROUND:The process of formation of the intervertebral disc structure remains poorly understood. Therefore, evaluating the forecasts for the development of the disc’s fibrous component as the foundation of its strength and elastic properties in the postnatal period seems appropriate.
 AIM:To identify microstructural transformations of the annulus fibrosus and nucleus pulposus in the fetal period and compare them with the ontogenetic orientation of the spinal motion segment.
 MATERIAL AND METHODS:The study material included 150intervertebral discs obtained during autopsy of 50fetuses. The gestational age of 42fetuses was in the early fetal period, 8fetuses were in the late fetal period. Intervertebral discs СV–СVI, ThV–ThVI, LV–SIwere examined in each fetus. All histological preparations were stained with hematoxylin and eosin, silver impregnation method, PAS reaction, Alcian blue (pH=1.0), Van Gieson and Weigert stains. For intergroup comparisons, the Kruskal–Wallis, Mann–Whitney, and Newman–Keuls tests were used. Differences were considered statistically significant atp≤0.05.
 RESULTS:Elastic fibers in the late fetal period were found in the annulus fibrosus and the peripheral zone of the nucleus pulposus. The intensity of staining of collagen and elastic fibers was more pronounced in the outer layers of the annulus fibrosus. Analysis of the parameters of the vascular-connective tissue formations showed an increase in their number (p=0.0368) and an increase in the number of vessels in the vascular-connective tissue formations of the intervertebral disc (p=0.0449) in the direction of the lower levels of the spinal motion segments. Differences in these two indicators were obtained between the СV–СVIand LV–SIdiscs, as well as between the СV–СVIand ThV–ThVIdiscs. In relation to all the studied morphometric parameters of the vascular-connective tissue formations in the cervical and thoracic spine, no statistically significant differences were obtained between the early and late fetal periods.
 CONCLUSION:The development of the intervertebral disc occurs from the peripheral parts to the center; the source for its further development is the fibrous ring.

Оценка согласованности специалистов ультразвуковой диагностики дегенеративных изменений межпозвонкового диска L5-S1

The article provides a detailed description of the application of techniques ofultrasound diagnostics of the spine using the L5-S1 intervertebral disc as an example. An assessment was made of the reproducibility and reliable determination of degenerative signs of the structure of the disc four indicators (heterogeneity of the nucleus pulposus, thinning of the fibrous ring, decrease in the height of the intervertebral disc, rupture/damage/"fissure" of the fibrous ring) based on the agreement of ultrasound diagnostic doctors and the application of statistical calculations using the κ criterion (Cohen's kappa).

Clinical study of Microendoscopic Discectomy + Fibrous Ring Suture Versus Microendoscopic Discectomy alone in the treatment of lumbar disc herniation in young and middle-aged patients.

To compare the clinical efficacy of microendoscopic discectomy + fibrous ring suture versus microendoscopic discectomy alone in the treatment of lumbar disc herniation (LDH) in young and middle-aged patients. A retrospective analysis was performed on the clinical data of 66 young and middle-aged patients with single-segment LDH diagnosed in Orthopedic Hospital of Henan Province from October 2019 to October 2022. All patients were divided into two groups: the microendoscopic discectomy + fibrous ring suture group and the microendoscopic discectomy alone group, with 33 cases in each group. The Visual Analogue Scale (VAS) and the Oswestry Disability Index (ODI) scores of the two groups were recorded before surgery and six and twelve months after surgery. Both groups completed the surgery and postoperative follow-up successfully and showed no statistically significant differences in terms of incision length, duration of surgery, intraoperative blood loss and length of hospital stay (all P>0.05). VAS, ODI and JOA scores were significantly improved in both groups at 6 and 12 months after surgery compared with those before surgery (all P<0.05). The two groups were similar in terms of excellent and good rates of postoperative modified MacNab Evaluation Criteria, with no statistically significant differences. No serious complications were observed in the two groups during and after surgery. Both of the two surgical methods are effective in the treatment of LDH in young and middle-aged patients, and microendoscopic discectomy + fibrous ring suture in particular may be preferred because it results in significant improvement in patients' VAS and ODI scores.

Ginsenoside Rg3 exhibits anti-catabolic and anti-apoptotic effects in IL-1β treated human disc nucleus pulposus cells and in a rat model of disc degeneration by inactivating the MAPK pathway.

Intervertebral disc degeneration (IDD) is the major cause of degeneration of joint diseases. IDD is characterized by a large number of apoptosis of nucleus pulposus cells (NPCs) and extracellular matrix (ECM) degradation. Ginsenoside Rg3 is the active component extracted from ginseng and has a vital function in modulating diseases. This study aimed to investigate the regulatory functions of ginsenoside Rg3 in IDD. We established the IDD cell model via inducing NPCs with IL-1β. The rat model of IDD was established by fibrous ring puncture method. Cell apoptotic capability was assessed through TUNEL assay. The levels of catabolic proteases MMPs and ADAMTSs were tested by western blot and RT-qPCR. IL-1β induction notably promoted the apoptosis of NPCs, while ginsenoside Rg3 treatment reversed the promoting function of IL-1β. Furthermore, we found that MMP2, MMP3, Adamts4, and Adamts5 levels were increased in IL-1β-induced NPCs, while ginsenoside Rg3 treatment markedly reduced their levels. Additionally, ginsenoside Rg3 was found to suppress the IL-1β-stimulated p38 MAPK pathway in NPCs. In the IDD rat model, we found that ginsenoside Rg3 treatment can alleviate NPC degeneration, recover the arrangement of annulus fibrous, and preserve more proteoglycan matrix. Moreover, ginsenoside Rg3 reduced apoptosis and catabolism and inactivated the p38 MAPK pathway in IDD rats. Ginsenoside Rg3 exhibits anti-catabolic and anti-apoptotic effects in IL-1β-stimulated NPCs and IDD rats by inactivating MAPK pathway.

A Report of Two Cases with Caseous Annular Calcification of the Mitral Valve.

Introduction: Caseous calcification of the mitral annulus (CCMA) is a rare variant of mitral annulus calcification, a chronic and degenerative mitral valve fibrous ring process. It usually carries a benign prognosis. The prevalence of CCMA is about 0.06%-0.07% of the population. CCMA is generally diagnosed incidentally and can be confused with other intracardiac masses such as cardiac tumors, abscesses, vegetation, or calcified thrombi. Multimodality imaging, including TEE, cardiac computed tomography, and cardiac magnetic nuclear resonance, can easily differentiate CCMA from other masses and help avoid unnecessary surgery. CCMA is typically located in the basal area of the posterior mitral valve, and the calcification seems like a round, large, soft mass with a central echo-dense location. CCMA may have a benign course, but it may sometimes be complicated with mitral valvular dysfunction, systemic embolization, or conduction abnormalities in the scenarios mentioned above, as well as when the diagnosis is unclear, surgery is indicated. Mitral valve replacement should be preferred compared to mitral valve repair.&#x0D; Conclusions: It is important to note that the decision for mitral valve replacement, including CAC cases, should be individualized based on various factors, including the patient's clinical condition, symptoms, severity of valve disease, and associated comorbidities.&#x0D; As scientific understanding and research progress, there may be ongoing developments and refinements in the conservative and surgical management of CCMA.

Barrier methods of prevention of epidural fibrosis at the lumbar level after microdiscectomy

The problem of cicatrical adhesion formation not only after microdiscectomies, but also after any spine surgery, remains unresolved to this day, being one of the main issues of spinal surgery. Several trigger mechanisms can be identified in the pathogenesis of epidural fibrosis formation: interaction of intervertebral cartilage components with surrounding tissues, disruption of vertebral canal integrity, dystrophy or complete absence of epidural fat, and presence of blood in the postoperative area. The pain syndrome associated with epidural fibrosis is persistent and increases after walking and prolonged being upright. There may be hyperaesthesia or hyperpathia in the innervation area of the affected roots and brisk tendon reflexes. Many authors are now trying to predict epidural fibrosis by analyzing immunological parameters and osteoprotegerin levels in blood serums, assessing anthropometric measures of patients, and examining the blood coagulation system. In modern neurosurgical society there is a clear view that epidural fibrosis should be prevented, but there are many prevention techniques. The following techniques have been identified: ligamentum flavum plasty and different variants of this operation, placement of an autograft from the inner flap of lumbar fascia into the intercostal space, use of autologous fat, use of fibrin glue, fibrous ring plasty, use of biodegradable membrane, application of anti-adhesion resorbable gel, insertion of wound drainage, use of amniotic sac, chitosan compounds in combination with L-glutamic acid, and many others.

Surgical treatment of cervical hernia using the ventral slot technique in a canine : Case report.

Degeneration of the intervertebral disc, popularly known as disc herniation, is characterized by calcification of the cartilaginous tissue originating from the nucleus pulposus or by bone metaplasia that extends to the fibrous ring, which may rupture and compress the bone marrow. The main clinical signs are cervical hyperpathy, ataxia, intense pain, muscle fasciculations and loss of proprioception in the limbs. Diagnosis is made through tomography or magnetic resonance imaging tests. There are two lines of treatment, conservative and surgical. The object of this work is to present a case report of intervertebral disc degeneration in a 6-year-old French bulldog dog, presenting a high degree of pain, surgical treatment performed using the ventral slot technique. Demonstrating the importance of knowledge of the pathology to choose the most appropriate treatment.

Electrospun short fibers: a new platform for cancer nanomedicine applications

With the continuous development of nanomaterials, nanofibers prepared by electrospinning have gradually occupied people’s vision because of their unique advantages, such as crisscross network and extracellular matrix-mimicking structure, high drug loading efficiency, and sustained release kinetics. Traditionally, electrospun fibers are mainly used as filter materials, wound dressings, and tissue engineering scaffolds, while their wide applications are limited to cancer nanomedicine applications due to their dense network structure. In recent years, two-dimensional fiber membranes have been transformed into short fibers that can be reconstructed to form fibrous rings or microspheres for cancer theranostics. Herein, this paper provides an overview of the recent advances in the design of electrospun short fibers that retain the advantages of nanofibers with good dispersibility for different nanomedicine applications, including cancer cell capture, cancer treatments, and cancer theranostics. The rational preparation of electrospun short fibers that are available to boost the development of nanomedicine is also discussed.

Electrospun short fibers: a new platform for cancer nanomedicine applications

With the continuous development of nanomaterials, nanofibers prepared by electrospinning have gradually occupied people’s vision because of their unique advantages, such as crisscross network and extracellular matrix-mimicking structure, high drug loading efficiency, and sustained release kinetics. Traditionally, electrospun fibers are mainly used as filter materials, wound dressings, and tissue engineering scaffolds, while their wide applications are limited to cancer nanomedicine applications due to their dense network structure. In recent years, two-dimensional fiber membranes have been transformed into short fibers that can be reconstructed to form fibrous rings or microspheres for cancer theranostics. Herein, this paper provides an overview of the recent advances in the design of electrospun short fibers that retain the advantages of nanofibers with good dispersibility for different nanomedicine applications, including cancer cell capture, cancer treatments, and cancer theranostics. The rational preparation of electrospun short fibers that are available to boost the development of nanomedicine is also discussed.

Comparison of 2 Anesthetic Methods for Transforaminal Endoscopic Lumbar Discectomy: A Prospective Randomized Controlled Study.

Randomized controlled trial. To compare the effect and safety of 2 anesthetic methods using in the operation of Transforaminal Endoscopic Lumbar Discectomy. From the January of 2020 to the December of 2021, 230 consecutive patients that underwent TELD were applied with two methods of anesthesia. All the patients were divided into two groups. The Monitored Anesthesia Care (MAC) group used the local anesthesia (LA) with MAC that based on the combination of dexmedetomidine and butorphanol tartrate. The LA group used the local anesthesia only. Then the Visual Analogic Scale (VAS) through the operating period was compared between the two groups at the time points of before operation (T0), inserting of the puncture needle (T1), establishing of the working cannula (T2), excision of the fibrous rings (T3) and immediately postoperatively (T4). Also, the satisfaction degree of the patients for the course of the operations and the occurrence of the complications were compared between the two groups. There were no differences of the VAS around the operating area at the time point of T0. Then the MAC group expressed lower scores at all other points of T1, T2, T3 and T4. Then the satisfaction degree of the MAC group was superior than the LA group. No difference was observed for the occurrence of the complications. MAC based on the combination of dexmedetomidine and butorphanol tartrate is an ideal method of anesthesia for TELD with enough effect and safety.