Mechanism Of Resorption Research Articles

Prevalence, clinical predictors, and mechanisms of resorption in lumbar disc herniation: a systematic review

Prevalence, clinical predictors, and mechanisms of resorption in lumbar disc herniation: a systematic review

Integrative proteome and metabolome analyses reveal molecular basis of the tail resorption during the metamorphic climax of Nanorana pleskei.

During the metamorphosis of anuran amphibians, the tail resorption process is a necessary and crucial change. One subject that has received relatively little or no attention is the expression patterns of proteins and metabolites in the different tail portions during metamorphosis, especially in highland amphibians. The mechanisms of tail resorption in three portions (the tip, middle and root) of the tail were investigated in N. pleskei G43 tadpole based on two omics (proteomic and metabolomic). Integrin αVβ3 was found to be high expressed in the distal portion of the tail, which could improve the sensitiveness to thyroid hormones in the distal portion of the tail. Muscle regression displayed a spatial pattern with stronger regression in distal and weaker one in proximal portion. Probably, this stronger regression was mainly performed by the proteases of proteasome from the active translation by ribosomes. The suicide model and murder model coexisted in the tail resorption. Meanwhile, fatty acids, amino acids, pyrimidine, and purine which derived from the breakdown of tissues can be used as building blocks or energy source for successful metamorphosis. Our data improved a better comprehension of the tail resorption mechanisms underlying the metamorphism of N. pleskei tadpole through identifying important participating proteins and metabolites.

Response characteristic and potential molecular mechanism of tail resorption in Bufo gargarizans after exposure to lead and copper, alone or combined

Tail resorption during amphibian metamorphosis is one of the most dramatic processes that is obligatorily dependent on thyroid hormone (TH). Heavy metals could result in thyroid gland damages and disturb TH homeostasis. Lead (Pb) and copper (Cu) often co-exist in natural aquatic ecosystems. However, there is still little information on how tail resorption responds to alone or combined exposure to Pb and Cu. Our study investigated the effects of Pb and Cu alone or combined exposure on the morphological parameters of the tail, histological changes of thyroid gland and tail, and gene expression programs involved in cell death of the tail in Bufo gargarizans tadpoles at the climax of metamorphosis. Results demonstrated that Pb, Cu and Pb–Cu mixture exposure resulted in a significantly longer tail compared with control. Damages to notochord, muscle, skin and spinal cord of the tail were found in Pb and Cu exposure groups. The colloid area, the height of follicular cells and number of phagocytic vesicles of thyroid gland in Pb–Cu mixture exposure groups were significantly reduced. In addition, the expression levels of TH, apoptosis, autophagy, degradation of cellular components and oxidative stress-related genes in the tail were significantly altered following Pb and Cu exposure. The present work revealed the relationship between environmental pollutants and tail resorption, providing scientific basis for amphibian protection.

New Intrinsic Ecological Mechanisms of Leaf Nutrient Resorption in Temperate Deciduous Trees.

Leaf nutrient resorption is a critical process in plant nutrient conservation during leaf senescence. However, the ecological mechanisms underlying the large variability in nitrogen (NRE) and phosphorous (PRE) resorption efficiencies among trees remain poorly understood. We conducted a comprehensive study on NRE and PRE variability using 61 tree individuals of 10 temperate broad-leaved tree species. Three potentially interrelated intrinsic ecological mechanisms (i.e., leaf senescence phenology, leaf pigments, and energy residual) were verified. We found that a delayed leaf senescence date, increased degradation of chlorophylls and carotenoids, biosynthesis of anthocyanins, and reduced nonstructural carbohydrates were all positively correlated with NRE and PRE at the individual tree level. The intrinsic factors affecting resorption efficiency were ranked in decreasing order of importance: leaf pigments > energy residual > senescence phenology. These factors explained more variability in NRE than in PRE. Our findings highlight the significance of these three ecological mechanisms in leaf nutrient resorption and have important implications for understanding how nutrient resorption responds to climate change.

Prediction and Mechanisms of Spontaneous Resorption in Lumbar Disc Herniation: Narrative Review.

The major symptoms of lumbar disc herniation (LDH) are low back pain, radiative lower extremity pain, and lower limb movement disorder. Patients with LDH suffer from great distress in their daily life accompanied by severe economic hardship and difficulty in self-care, with an increasing tendency in the aging population. PubMed and the Cochrane Central Register of Controlled Trials were searched for relevant studies of spontaneous resorption or regression in LDH after conservative treatment and for other potential studies, which included those from inception to June 30, 2023. The objective of this narrative review is to summarize previous literatures about spontaneous resorption in LDH and to discuss the mechanisms and influencing factors in order to assess the probability of spontaneous resorption by conservative treatment. Spontaneous resorption without surgical treatment is influenced by the types and sizes of the LDH, inflammatory responses, and therapeutic factors. If the lumbar disc herniated tissue comprises a higher percentage of cartilage or modic changes have been shown on magnetic resonance imaging (MRI), resorption in LDH is prevented. The bull's eye sign on enhanced MRI, which is a ring enhancement around a protruding disc, is a vital indicator for easy reabsorption. In addition, the type of extrusion and sequestration in LDH could forecast the higher feasibility of natural reabsorption. Moreover, the higher the proportion of protrusion on the intervertebral disc tissue within the spinal canal, the greater the likelihood of reabsorption. Therefore, which illustrates the feasibility of conservative treatments for LDH. Nonsurgical management of LDH with clinical symptoms is recommended by the authors.

Value and Role of Obesity and Metabolic Surgery in the Study of Human Medicine, Academic Teaching and Advanced Training

In teaching, obesity and metabolic surgery play only a limited role. However, due to the rapidly increasing number of surgical interventions, communication of knowledge in the study of human medicine as well as in gastroenterological and surgical residency (general and abdominal surgery) is required.Narrative review. · Currently, lectures on obesity and metabolic surgery do not belong to the current surgical curriculum of human medicine at all University Medical Schools, which needs to be absolutely established step by step - based on their topicality and importance in the clinical spectrum of clinical care.. · This rapidly developing special area of abdominal surgery is characterized by specific and diverse interdisciplinarity.. · Multimorbidity, changes in resorption mechanisms but also psychological changes have a substantial impact on the indication and patient outcome.. · The increase in endoscopic, surgical and also robotic interventions and surgical methods in this special field requires a broad knowledge of all surgical disciplines in intervention preparation, perioperative and follow-up management of obesity-associated basic diagnosis. This objective is important even in the study of human medicine and further advanced training.. The inclusion of such complex contents on obesity and metabolic surgery into surgical teaching and into residency of general and abdominal surgery is essential to be future-oriented and prepared for the development of the discipline.

Resorption of lumbar disc herniations: a non-systematic literature review

Objective. To analyze the information on spontaneous resorption of lumbar disc herniation.Material and Methods. A non-systematic review of 37 publications on resorption of disc herniation was conducted. The data on the timing, mechanisms and predictors of regression of lumbar disc herniation were summarized. A clinical case is presented illustrating the resorption of a herniated L4–L5 intervertebral disc over 8 months.Results. The frequency and timing of resorption of lumbar disc herniation vary depending on the number of patients, follow-up period, the type and nature of the hernial bulging, and other characteristics of patients. The results of meta-analyses indicate that the average period of spontaneous resorption of lumbar disc herniation is more than 6 months. The main theories of spontaneous resorption of lumbar disc herniation are the dehydration theory, the mechanical theory, and mechanisms associated with inflammatory processes and neovascularization. Currently, predictors of disc herniation resorption include the type and size of the hernia, follow-up period, Modic changes, etc. Existing data on the timing, mechanisms and predictors of resorption of lumbar disc herniation are insufficient to improve treatment tactics for this category of patients.Conclusion. Herniated lumbar intervertebral discs tend to undergo spontaneous regression which, however, is not observed in all patients. The mechanisms of resorption can be different, and the fact of resorption itself can occur in different types of hernia with different frequencies. An analysis of large data sets is necessary to more accurately determine the timing and predictors of resorption of lumbar disc hernias.

Choroid plexuses carry nodal-like cilia that undergo axoneme regression from early adult stage

Choroid plexuses (ChPs) produce cerebrospinal fluid and sense non-cell-autonomous stimuli to control the homeostasis of the central nervous system. They are mainly composed of epithelial multiciliated cells, whose development and function are still controversial. We have thus characterized the stepwise order of mammalian ChP epithelia cilia formation using a combination of super-resolution-microscopy approaches and mouse genetics. We show that ChP ciliated cells are built embryonically on a treadmill of spatiotemporally regulated events, starting with atypical centriole amplification and ending with the construction of nodal-like 9+0 cilia, characterized by both primary and motile features. ChP cilia undergo axoneme resorption at early postnatal stages through a microtubule destabilization process controlled by the microtubule-severing enzyme spastin and mitigated by polyglutamylation levels. Notably, this phenotype is preserved in humans, suggesting a conserved ciliary resorption mechanism in mammals.

Relationship between orthodontic treatment and root resorption

As one of the common complications of orthodontic treatment, external apical root resorption (EARR) often occurs during orthodontic treatment. This paper systematically elaborates the degree classification of EARR and the biological mechanism of root resorption in orthodontic treatment. At the same time, orthodontic root resorption is caused by a variety of factors. They are not only affected by genetic and environmental factors, but also by great individual differences. This paper summarizes the factors influencing the root resorption of orthodontic teeth and the prognosis of root resorption. This paper also provides some suggestions for the prevention and treatment of root resorption in the process of orthodontics, in order to provide guidance and help for the clinical work of orthodontists.

Multidisciplinary Utilization of Surgi-plaster: Chemical, Physical, Biological Properties and Mechanisms of Action and Resorption

Multidisciplinary Utilization of Surgi-plaster: Chemical, Physical, Biological Properties and Mechanisms of Action and Resorption

Regulation mechanisms underlying tail resorption in Bufo gargarizans metamorphosis

Anurans have been excellent organisms for studying amphibian metamorphosis. Tail resorption is a remarkable event that occurs during amphibian metamorphosis. Although tail resorption has been previously studied in other anurans like Xenopus laevis and Rana chensinensis, there is no report on Bufo gargarizans. This paper thus explored the mechanism of tail resorption during metamorphosis in Bufo gargarizans tadpoles through some biological research methods. Histological results showed that the tail tissues of tadpoles gradually degraded as metamorphosis progressed. RNA sequencing analysis was performed to examine the expression level and functional enrichment of differentially expressed genes in the tail. In addition, we analyzed the mRNA expression levels of genes related to tail resorption by quantitative real-time polymerase chain reaction. We also speculated on three pathways that participate in the regulation of tail resorption based on the above results. The present study might provide a theoretical basis and novel insights for further research of complex molecular mechanisms of tail resorption in amphibians.

Leaf nutrient resorption of two life-form tree species in urban gardens and their response to soil nutrient availability.

Leaf nutrient resorption is a key strategy in plant conservation that minimizes nutrient loss and enhances productivity. However, the differences of the nutrient resorption among garden tree species in urban ecosystems were not clearly understood, especially the differences of nitrogen resorption efficiency (NRE) and phosphorous resorption efficiency (PRE) between evergreen and deciduous trees. We selected 40 most generally used garden tree specie belonged two life forms (evergreen and deciduous) and investigated the nitrogen (N) and phosphorus (P) concentrations in green and senesced leaves and soil nutrient concentrations of nine samples trees for each species. Then, the nutrient concentrations and resorption efficiency were compared, and the soil nutrients utilization strategies were further analyzed. The results showed that the N concentration was significantly higher in the green and senesced leaves of deciduous trees than in the leaves of evergreen trees. The two life-form trees were both N limited and evergreen trees were more sensitive to N limitation. The NRE and PRE in the deciduous trees were significantly higher than those in the evergreen trees. The NRE was significantly positively correlated with the PRE in the deciduous trees. As the soil N and P concentrations increased, the nutrient resorption efficiency (NuRE) of the evergreen trees increased, but that of the deciduous trees decreased. Compared with the deciduous trees, the evergreen trees were more sensitive to the feedback of soil N and P concentrations. These findings reveal the N and P nutrient resorption mechanism of evergreen and deciduous trees and fill a gap in the understanding of nutrient resorption in urban ecosystems.

HIF-1α regulates osteoclastogenesis and alveolar bone resorption in periodontitis via ANGPTL4

ObjectiveThe mechanism of alveolar bone resorption caused by periodontitis is not fully understood. We sought to investigate whether microenvironmental changes of local hypoxia are involved in these processes. MethodsIn this study, periodontitis models of control mice and knockout of Hypoxia Induced Factor 1α (HIF-1α) harboring Cathepsin K (CTSK) Cre mice were constructed to study the effect of osteoclasts affected by hypoxic environment on alveolar bone resorption. RAW264.7 cells were subsequently induced by CoCl2 to observe the effects of HIF-1α and Angiopoietin-like Protein 4 (ANGPTL4) on osteoblast differentiation and fusion. ResultsThe degree of alveolar bone resorption in the periodontitis tissues was lesser in mice with conditional knockout of HIF-1α in osteoclasts than in wild-type mice. We also observed that HIF-1α conditional knockout mice had fewer osteoclasts on the alveolar bone surface than control mice. HIF-1α increases the expression of ANGPTL4 and promotes the differentiation of RAW264.7 cells into osteoblasts and cell fusion under chemically simulated hypoxic conditions. ConclusionHIF-1α regulates osteoclastogenesis and participates in bone resorption in periodontitis through ANGPTL4.

A conserved tooth resorption mechanism in modern and fossil snakes

Whether snakes evolved their elongated, limbless bodies or their specialized skulls and teeth first is a central question in squamate evolution. Identifying features shared between extant and fossil snakes is therefore key to unraveling the early evolution of this iconic reptile group. One promising candidate is their unusual mode of tooth replacement, whereby teeth are replaced without signs of external tooth resorption. We reveal through histological analysis that the lack of resorption pits in snakes is due to the unusual action of odontoclasts, which resorb dentine from within the pulp of the tooth. Internal tooth resorption is widespread in extant snakes, differs from replacement in other reptiles, and is even detectable via non-destructive μCT scanning, providing a method for identifying fossil snakes. We then detected internal tooth resorption in the fossil snake Yurlunggur, and one of the oldest snake fossils, Portugalophis, suggesting that it is one of the earliest innovations in Pan-Serpentes, likely preceding limb loss.

Integrin expression and extracellular matrix adhesion of septoclasts, pericytes, and endothelial cells at the chondro-osseous junction and the metaphysis of the proximal tibia in young mice.

We previously reported that septoclasts, which are uncalcified growth plate (GP) cartilage matrix-resorbing cells, are derived from pericytes surrounding capillary endothelial cells. Resorption of the GP is assumed to be regulated synchronously by septoclasts, pericytes, and endothelial cells. To reveal the contribution of the extracellular matrix (ECM) to the regulatory mechanisms of septoclastic cartilage resorption, we investigated the spatial correlation between the cells and the ECM in the GP matrix and basement membrane (BM) and investigated the expression of integrins-ECM receptors-in the cells. Septoclasts attached to the transverse septa containing collagen-II/-X at the tip of their processes and to the longitudinal septa containing collagen-II/-X at the spine-like processes extending from their bodies and processes. Collagen-IV and laminin α4 in the BM were sparsely detected between septoclasts and capillary endothelial cells at the chondro-osseous junction (COJ) and were absent in the outer surface of pericytes at the metaphysis. Integrin α1/α2, integrin α1, and integrin α2/α6 were detected in the cell membranes of septoclasts, pericytes, and endothelial cells, respectively. These results suggest that the adhesion between septoclasts and the cartilage ECM forming the scaffolds for cartilage resorption and migration is provided by integrin α2-collagen-II/-X interaction and that the adhesions between the BM and pericytes or endothelial cells are mediated by integrin α1-collagen-IV and integrin α2/α6-laminin interaction, respectively.

Cathepsin K degrades osteoprotegerin to promote osteoclastogenesis in vitro

Osteoblasts produce the receptor activator of nuclear factor-kappa B ligand (RANKL) and osteoprotegerin, the inducer and the suppressor of osteoclast differentiation and activation. We previously proposed that the degradation of osteoprotegerin by lysine-specific gingipain of Porphyromonas gingivalis and neutrophil elastase is one of the mechanisms of bone resorption associated with infection and inflammation. In the present study, we found that cathepsin K (CTSK) also degraded osteoprotegerin in an acidic milieu and the buffer with a pH of 7.4. The 37k fragment of osteoprotegerin produced by the reaction with CTSK was further degraded into low molecular weight fragments, including a 13k fragment, depending on the reaction time. The N-terminal amino acid sequence of the 37k fragment matched that of the intact osteoprotegerin, indicating that CTSK preferentially hydrolyzes the death domain-like region of osteoprotegerin, not its RANKL-binding region. The 13k fragment of osteoprotegerin was the C-terminal 13k portion within the RANKL-binding region of the 37k fragment. Finally, CTSK restored RANKL-dependent osteoclast differentiation that was suppressed by the addition of osteoprotegerin. Collectively, CTSK is a possible positive regulator of osteoclastogenesis.

IL-6 Plays a Critical Role in Stromal Fibroblast RANKL Induction and Consequent Osteoclastogenesis in Ameloblastoma Progression

Ameloblastoma (AB) is the most common benign, epithelial odontogenic tumor that occurs in the jawbone. AB is a slow-growing, benign epithelial tumor but shows locally invasive growth, with bone resorption or recurrence if not adequately resected. From these points of view, understanding the mechanism of AB-induced bone resorption is necessary for better clinical therapy and improving patients’ quality of life. In bone resorption, osteoclasts play critical roles, and RANKL is a pivotal regulator of osteoclastogenesis. However, the source of RANKL-expressing cells in the AB tumor microenvironment is controversial, and the mechanism of osteoclastogenesis in AB progression is not fully understood. In this study, we investigated the distribution of the RNA expression of RANKL in AB specimens. We found that PDGFRα- and S100A4-positive stromal fibroblasts expressed RANKL in the AB tumor microenvironment. Moreover, we analyzed the mechanisms of osteoclastogenesis in the AB tumor microenvironment using the human AB cell line AM-1 and a human primary periodontal ligament fibroblast cells. The results of histopathologic and in vitro studies clarified that the interaction between AB cells and stromal fibroblasts upregulated IL-6 expression and that AB cells induced RANKL expression in stromal fibroblasts and consequent osteoclastogenesis in AB progression.

IL-1 Generated by Oral Squamous Cell Carcinoma Stimulates Tumor-Induced and RANKL-Induced Osteoclastogenesis: A Possible Mechanism of Bone Resorption Induced by the Infiltration of Oral Squamous Cell Carcinoma.

We previously observed a novel osteoclastogenesis system that is induced by oral squamous cell carcinoma (OSCC) cells, which target osteoclast precursor cells (OPC) without upregulation of the master transcriptional factor of osteoclastogenesis, NFATc1. Here, we analyzed inflammatory cytokines that were preferentially expressed in one of the osteoclastogenic OSCC cell lines, namely NEM, compared with the subclone that had lost its osteoclastogenic properties. Based on a gene expression microarray and a protein array analyses, IL-1, IL-6, IL-8, and CXCL1 were chosen as candidates responsible for tumor-induced osteoclastogenesis. From the results of the in vitro osteoclastogenesis assay using OPCs cultured with OSCC cells or their culture supernatants, IL-1 was selected as a stimulator of both OSCC-induced and RANKL-induced osteoclastogenesis. The IL-1 receptor antagonist significantly attenuated osteoclastogenesis induced by NEM cells. The stimulatory effects of IL-1 for OSCC-induced and RANKL-induced osteoclastogenesis were effectively attenuated with cannabidiol and denosumab, respectively. These results suggest that IL-1 secreted from OSCC cells stimulates not only tumor-induced osteoclastogenesis targeting OPCs but also physiological RANKL-induced osteoclastogenesis, and this may be the biological mechanism of bone resorption induced by the infiltration of OSCC. These results also suggest that IL-1 inhibitors are candidates for therapeutic agents against bone resorption induced by OSCC.

Cerebrospinal Fluid Ascitis: Late Complication of A Ventriculo-Peritoneal Bypass

Cerebrospinal fluid (CSF) ascites is a rare complication of ventriculoperitoneal shunt (PVD). The etiological factors and especially the mechanisms underlying this complication remain difficult to explain. We report the case of a voluminous CSF ascites complicating a DVP, 15 years later. This is a 16-year-old patient, valved at the age of one year, admitted for major abdominal distension. The abdominal scanner shows a large free fluid collection in the peritoneal cavity. The puncture of this ascites and above all the conversion of the DVP into a ventriculo-atrial bypass allowed the collection to dry up. The various hypotheses mentioned in the literature struggle to explain the occurrence of ascites in this patient. This ascites seems to stem from a progressive failure of the mechanisms of peritoneal resorption over time and this apart from any primary peritoneal pathology.

Up-Regulation of Interleukins (ILS) and their Potential Role in the Pathogenesis of Radicular Cyst

Objective: Study the upregulation of Interleukin levels and their potential role in the pathogenesis of radicular cysts Study Design: Cross-sectional study Place and Duration: Institute of Molecular Biology and Biotechnology (IMBB), The University of Lahore, (9-10 Months) Martials and Methods: Hundred samples were extracted from both diseased and healthy individuals and tissue homogenates were prepared. MDA and LPS were estimated with the help of spectrophotometric method. IL1, IL-6, TNF-α and MMP-9 were determined by their commercial ELISA kits. Results: Malondialdehyde (MDA) was significantly (p=0.033) higher (3.99±0.99 Vs .95±0.011) in diseased group as compared to control. Higher levels of IL-1 (pg/ml) (6.59±1.56 Vs 4.56±1.23), IL-6 (pg/ml) (7.65±1.41 Vs 5.99±0.219) and TNF-α (pg/ml) (31.55±4.55 Vs 20.55±3.28) were recorded in the diseased group. In the group of patients, MMP-9 remained significantly increased when compared with the healthy controls in the case of subjects it remained (93.25±6.48 ng/ml) while in controls they were (47.22±5.29 ng/ml). Likewise in the case of LPS it was significantly increased in the group of radicular cyst (17.25±4.26 pg/ml) as compared to healthy controls (125.25±9.28 pg/ml). Conclusion: Present study indicates the significant correlation of LPS with the pathogenesis of radicular cyst. Moreover, it indicates that as the oxidative stress is increased, it increases the expression of several ILs and MMP-9 that contribute in the pathogenesis of radicular cyst. Further studies may describe the role of lipopolysaccharide and other potential variables to enable better understanding about bone resorption mechanism in periapical cyst development. Keywords: Interleukins, Lipopolysaccharides (LPS), Malondialdehyde (MDA), MMP-9, Radicular Cyst.