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Abnormal epigenetics is the initial factor of the occurrence and development of osteoarthritis (OA), and abnormal mechanical load is a key pathogenic factor of OA. However, how abnormal mechanical load affects chondrocyte epigenetics is unclear. Chondrocytes reportedly respond to mechanics through the extracellular matrix (ECM), which has a role in regulating epigenetics in various diseases, and mitochondria are potential mediators of communication between mechanics and epigenetics. Therefore, it is hypothesized that the matrix mechanics of cartilage regulates their epigenetics through mitochondria and leads to OA. The matrix stiffness of OA cartilage on the stress-concentrated side increases, mitochondrial damage of chondrocyte is severe, and the chondrocyte H3K27me3 is demethylated. Moreover, mitochondrial permeability transition pore (mPTP) opens to increase the translocation of plant homeodomain finger protein 8 (Phf8) into the nucleus to catalyze H3K27me3 demethylation. This provides a new perspective for us to understand the mechanism of OA based on mechanobiology.
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Purpose: To investigate the correlation between apparent diffusion coefficient (ADC) histograms and high-risk clinicopathologic features related to uveal melanoma (UM) prognosis. Methods: This retrospective study included 53 patients with UM who underwent diffusion-weighted imaging (DWI) between August 2015 and March 2024. Axial DWI was performed with a single-shot spin-echo echo-planar imaging sequence. ADC histogram parameters of ADCmean, ADC50%, interquartile range (IQR), skewness, kurtosis, and entropy were obtained from DWI. The relationships between histogram parameters and high-risk clinicopathological characteristics including tumor size, preoperative retinal detachment, histological subtypes, Ki-67 index, and chromosome status, were analyzed by Spearman correlation analysis, Mann-Whitney U test, or Kruskal-Wallis test. Results: A total of 53 patients (mean ± SD age, 55 ± 15 years; 22 men) were evaluated. The largest basal diameter (LBD) was correlated with kurtosis (r = 0.311, P = 0.024). Tumor prominence (TP) was correlated with entropy (r = 0.581, P < 0.001) and kurtosis (r = 0.273, P = 0.048). Additionally, significant correlations were identified between the Ki-67 index and ADCmean (r = -0.444, P = 0.005), ADC50% (r = -0.487, P = 0.002), and skewness (r = 0.394, P = 0.014). Finally, entropy was correlated with monosomy 3 (r = 0.541, P = 0.017). Conclusions: The ADC histograms provided valuable insights into high-risk clinicopathologic features of UM and hold promise in the early prediction of UM prognosis.
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Imagem de Difusão por Ressonância Magnética , Melanoma , Neoplasias Uveais , Humanos , Neoplasias Uveais/patologia , Neoplasias Uveais/genética , Masculino , Feminino , Pessoa de Meia-Idade , Melanoma/patologia , Estudos Retrospectivos , Prognóstico , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Idoso , Imagem Ecoplanar/métodosRESUMO
Luminescence thermometry is a promising non-contact temperature measurement technique, but improving the precision and reliability of this method remains a challenge. Herein, we propose a thermal sensing strategy based on a machine learning. By using Gd3Ga5O12: Er3+-Yb3+ as the sensing medium, a support vector machine (SVM) is preliminarily adopted to establish the relationship between temperature and upconversion emission spectra, and the sensing properties are discussed through the comparison with luminescence intensity ratio (LIR) and multiple linear regression (MLR) methods. Within a wide operating temperature range (303-853â K), the maximum and the mean measurement errors actualized by the SVM are just about 0.38 and 0.12â K, respectively, much better than the other two methods (3.75 and 1.37â K for LIR and 1.82 and 0.43â K for MLR). Besides, the luminescence thermometry driven by the SVM presents a high robustness, although the spectral profiles are distorted by the interferences within the testing environment, where, however, LIR and MLR approaches become ineffective. Results demonstrate that the SVM would be a powerful tool to be applied on the luminescence thermometry for achieving a high sensing performance.
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In this study, a sump in the Xingdong coal mine (buried at a depth of over 1200 m) was used to analyze the surrounding rock's stability and control technology. Under the combined influences of various complex conditions, such as the burial depth of over 1200 m, ultra-high ground stress, and location under the goaf, the sump support became extremely difficult, severely restricting the efficient production of the mine. The overall pressure-relief mechanisms and degree of the sump surrounding the rock environment under the goaf were studied, and the rationality of the sump location was verified through numerical simulations and field tests. A more effective support scheme was proposed based on the deformation characteristics and failure mechanisms of the temporary sump-surrounding rock under the supporting conditions. The combined control technology employed the lengthened strong anchor bolts (cables), full-section concrete-filled steel tubular supports, and pouring full-section reinforced concrete and full-section long-hole grouting reinforcement. The field test results showed that after adopting the new support scheme, the sump-surrounding rock tended to be stable after three months. The sump roof subsidence amount, floor heave amount, and convergence of the two sidewalls of the sump were 17.2-19.2 mm, 13.9-16.5 mm, and 23.2-27.9 mm, respectively, thus satisfying the application requirements. This study provides an essential reference for deep-mine roadway support under a complex high-ground-stress environment.
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Asma , Doença Pulmonar Obstrutiva Crônica , Humanos , Sepultamento , Reforço Psicológico , TecnologiaRESUMO
Hydraulic flushing gas extraction technology is gradually being applied in coal mines because it can effectively improve the gas extraction efficiency. This study aimed to explore the effect of strain-softening on permeability and gas pressure, due to the deficiency of previous studies on hydraulic flushing that did not consider the strain-softening of surrounding rocks. First, we analyzed the essence of strain-softening based on previous studies and proved the existence of strain-softening in surrounding rocks of the hydraulic flushing borehole by a field example. Subsequently, we established gas extraction models for different borehole diameters with and without considering strain-softening through the permeability evolution equation, the gas migration equation, and the strain-softening equation. We found that strain-softening significantly effects the permeability and gas pressure of the surrounding rocks of the borehole: the larger the diameter, the greater the effect on strain-softening. Compared with strain-softening not considered, the permeability, the permeability increase range, and the gas extraction standard range in surrounding rocks of hydraulic flushing boreholes will increase under the same borehole diameter when strain-softening is considered. The borehole diameter increases from 0.113 to 0.7 m, and the increases in permeability are 592.76 × 10-12, 614.25 × 10-12, 615.13 × 10-12, and 655.29 × 10-12 m2, respectively, the increases in permeability increase radius are 0.050, 0.121, 0.193, and 0.255 m, respectively, and the increase in gas extraction standard range radius under the two indicators are 0.119, 0.124, 0.190, 0.253 m and 0.052, 0.102, 0.150, 0.191 m, respectively. The gas pressure distribution in surrounding rocks of the borehole will also be changed by considering strain-softening, resulting in a slowly increasing gas pressure zone near the borehole: the larger the diameter, the greater the zone. Our research results proved that it is necessary to consider the strain-softening of surrounding rocks when studying gas extraction through hydraulic flushing boreholes. Moreover, we provide a novel explanation for the mechanism of gas extraction through hydraulic flushing boreholes based on the study's results. The finding of this study can help better understand the mechanism of enhanced gas extraction through hydraulic flushing boreholes.
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This paper proposes a new montmorillonite-type multiple network composite gel for the prevention of coal spontaneous combustion. The first network is formed by the cross-linking of polyvinyl alcohol (PVA) and boric acid under alkaline conditions. The second network is formed as a result of intermolecular hydrogen-bonding interactions between polyacrylamide (PAM) and polyvinyl alcohol. Montmorillonite (MMT) is designed as the backbone material in the preparation of composite gels. The optimal ratios of the reactants of the composite gel were determined through orthogonal experiments. The experimental results showed that PVA had the greatest influence on the gelation time, whereas the PAM concentration had the strongest influence on the gel permeability. The optimal blending ratio was 4% MMT + 2.5% PVA + 1.5% PAM. The chemical performances of the composite colloids, such as inhibition rate, reactive functional groups, and kinetics, were investigated. Results showed that multiple network composite gels could effectively inhibit the coal spontaneous combustion reaction. Based on the principle of coal spontaneous combustion and the cross-linking network structure of the composite gel, the flame-retardant and fire-extinguishing mechanisms were also explored in terms of both physical and chemical inhibition pathways.
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To reduce the filling cost of high-water backfilling material (HWBM) in mining backfill and improve the recycling utilization of the industrial waste such as the coal fly ash. The ultra-fine fly ash (UFA) was added to the HWBM as a partial replacement in this work. Therefore, a series of experiments were performed to investigate the effect of UFA on the mechanical properties of the HWBM at the different curing conditions, then the hydration mechanism of the HWBM blended with UFA was analyzed by XRD and SEM method. The result indicates that the strength of the HWBM decreased with the increasing of UFA dosages, but the addition of UFA can improve the residual strength of the initial HWBM. Additionally, when the HWBM was cured at the laboratory air condition, its carbonation process was restrained obviously as the UFA dosages were less than 15% at the ages of 28 days, which indicates the UFA can improve the weathering resistance of the HWBM with the curing ages increasing effectively. The XRD and SEM results also shows that the degree of crystallinity of the HWBM increased when UFA dosages were less than 15% effectively, while there were few obvious changes on types of hydration products. It indicates that the main affects of UFA on the performance of HWBM is filler and dilution, which reduced the contact area between hydration products of HWBM and CO2 in the air, further improved the carbonation resistance of HWBM.
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INTRODUCTION: The postoperative survival of oral squamous cell carcinoma (SCC) relies on precise detection and complete resection of original tumors. The mucosal extension of the tumor is evaluated visually during surgery, but small and flat foci are difficult to detect. Real-time fluorescence imaging may improve detection of tumor margins. MATERIALS AND METHODS: In the current study, a peptide-based near-infrared (NIR) fluorescence dye, c-MET-binding peptide-indocyanine green (cMBP-ICG), which specifically targets tumor via c-MET binding, was synthetized. A prospective pilot clinical trial then was conducted with oral SCC patients and intraoperatively to assess the feasibility of cMBP-ICG used to detect tumors margins. Fluorescence was histologically correlated to determine sensitivity and specificity. RESULTS: The immunohistochemistry (IHC) results demonstrated increased c-Met expression in oral SCC compared with normal mucosa. Tumor-to-background ratios ranged from 2.71 ± 0.7 to 3.11 ± 1.2 in different concentration groups. From 10 patients with oral SCC, 60 specimens were collected from tumor margins. The sensitivity and specificity of discriminative value derived from cMBP-ICG application in humans were respectively 100% and 75%. CONCLUSIONS: Topical application of cMBP-ICG is feasible and safe for optimizing intraoperative visualization and tumor margin detection in oral SCC patients, which could clinically increase the probability of complete resections and improve oncologic outcomes.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Bucais/cirurgia , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Verde de Indocianina , Corantes Fluorescentes , Estudos Prospectivos , PeptídeosRESUMO
Background: Osteogenesis and angiogenesis are important for bone fracture healing. Irisin is a muscle-derived monokine that is associated with bone formation. Methods: To demonstrate the effect of irisin on bone fracture healing, closed mid-diaphyseal femur fractures were produced in 8-week-old C57BL/6 mice. Irisin was administrated intraperitoneally every other day after surgery, fracture healing was assessed by using X-rays. Bone morphometry of the fracture callus were assessed by using micro-computed tomography. Femurs of mice from each group were assessed by the three-point bending testing. Effect of irisin on osteogenic differentiation in mesenchymal stem cells in vitro was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR), alkaline phosphatase staining and alizarin red staining. Angiogenesis of human umbilical vein endothelial cells (HUVECs) were evaluated by qRT-PCR, migration tests, and tube formation assays. Results: Increased callus formation, mineralization and tougher fracture healing were observed in the irisin-treated group than in the control group, indicating the better fracture callus healing due to Irisin treatment. The vessel surface and vessel volume fraction of the callus also increased in the irisin-treated group. The expression of BMP2, CD31, and VEGF in callus were enhanced in the irisin-treated group. In mouse bone mesenchymal stem cells, irisin promoted ALP expression and mineralization, and increased the expression of osteogenic genes, including OSX, Runx2, OPG, ALP, OCN and BMP2. Irisin also promoted HUVEC migration and tube formation. Expression of angiogenic genes, including ANGPT1, ANGPT2, VEGFb, CD31, FGF2, and PDGFRB in HUVECs were increased by irisin. Conclusion: All the results indicate irisin can promote fracture healing through osteogenesis and angiogenesis. These findings help in the understanding of muscle-bone interactions during fracture healing. The Translational Potential of this Article: Irisin was one of the most important monokine secreted by skeletal muscle. Studies have found that irisin have anabolic effect one bone remodeling through affecting osteocyte and osteoblast. Based on our study, irisin could promote bone fracture healing by increasing bone mass and vascularization, which provide a potential usage of irisin to promote fracture healing and improve clinical outcomes.
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Introduction: As the space field has developed and our population ages, people engaged in space travel and those on prolonged bed rest are at increasing risk for bone loss and fractures. Disuse osteoporosis occurs frequently in these instances, for which the currently available anti-osteoporosis agents are far from satisfactory and have undesirable side effects. CEFFE is a cell-free fraction isolated from nanofat that is enriched with a variety of growth factors, and we aim to investigate its potential therapeutic effects on disuse osteoporosis. Methods: A tail suspension-induced osteoporosis model was applied in this study. Three weeks after tail suspension, CEFFE was intraperitoneally injected, and PBS was used as a control. The trabecular and cortical bone microstructures of the tibia in each group were assessed by µCT after 4 weeks of administration. Osteocyte lacunar-canalicularity was observed by HE and silver staining. In vitro, MLO-Y4 cell apoptosis was induced by reactive oxygen species (ROSUP). TUNEL staining and flow cytometry were used to detect apoptosis. CCK-8 was used to detect cell proliferation, and Western blotting was used to detect MAPK signaling pathway changes. Results: CEFFE increased the bone volume (BV/TV) and trabecular number (Tb.N) of the trabecular bone and increased the thickness of the cortical bone. HE and silver staining results showed that CEFFE reduced the number of empty lacunae and improved the lacuna-canalicular structure. CEFFE promoted osteocyte proliferative capacity in a dose-dependent manner. CEFFE protected MLO-Y4 from apoptosis by activating the serine/threonine-selective protein kinase (ERK) signaling pathways. Conclusion: CEFFE attenuated immobilization-induced bone loss by decreasing osteocyte apoptosis. CEFFE increased the survival of osteocytes and inhibited osteocyte apoptosis by activating the ERK signaling pathway in vitro.
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BACKGROUND/OBJECTIVE: Subchondral bone marrow lesions (BMLs) are common magnetic resonance imaging (MRI) features in joints affected by osteoarthritis (OA), however, their clinical impacts and mechanisms remain controversial. Thus, we aimed to investigate subchondral BMLs in knee OA patients who underwent total knee arthroplasty (TKA), then evaluate the associations of osteoclastogenesis and nerve growth in subchondral BMLs with clinical symptoms. METHODS: Total 70 patients with primary symptomatic knee OA were involved, then separated into three groups based on MRI (without BMLs group, n â= â14; BMLs without cyst group, n â= â37; BMLs with cyst group, n â= â19). Volume of BMLs and cyst-like lesions was calculated via the OsiriX system. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire was used to assess clinical symptoms. Histology and immunohistochemistry were deployed to assess subchondral osteoclastogenesis and nerve distribution. Pearson's correlation coefficient was used to evaluate the associations between volume of BMLs and joint symptoms, and to assess the associations of osteoclastogenesis and nerve growth in subchondral BMLs with joint symptoms. RESULTS: In BMLs combined with cyst group, patients exhibited increased osteoclastogenesis and nerve distribution in subchondral bone, as shown by increased expression of tartrate resistant acid phosphatase (TRAP) and protein gene product 9.5 (PGP9.5). Volume of subchondral cyst-like component was associated with joint pain (p â< â0.05). Subchondral osteoclastogenesis and nerve distribution were positively associated with joint pain in BMLs with cyst group (p â< â0.05). CONCLUSION: The subchondral cyst-like lesion was an independent factor for inducing pain in OA patients; osteoclastogenesis and nerve growth in subchondral cyst-like lesions could account for this joint pain. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: Our results indicated that the increased osteoclastogenesis and nerve growth in subchondral cyst-like lesions could account for the pain of OA joints. These findings may provide valuable basis for the treatment of OA.
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OBJECTIVE: This study aimed to investigate the abnormal subchondral trabecular bone (STB) remodeling in knee osteoarthritis (OA) under the influence of knee alignment [hip-knee-ankle (HKA) angle]. DESIGN: Forty-one patients with knee OA underwent radiographic examination before total knee arthroplasty (TKA) for the measurement of HKA angle. Tibial plateau specimens obtained during TKA were used for histomorphometric analyses to assess STB remodeling and cartilage degradation. Tartrate-resistant acidic phosphatase (TRAP) staining was used to test osteoclast activity. Osterix, osteocalcin, and sclerostin expression in the STB were determined using immunohistochemistry. RESULTS: The interaction between HKA angle and side (medial vs lateral of tibial plateau) was the main significant influence factor for STB remodeling and microstructure. The STB with the deviation of the knee alignment was accompanied by obvious abnormal bone remodeling and microstructural sclerosis. Bone volume fraction (BV/TV) was the only significant influence factor for OARSI score, the larger the BV/TV of STB, the higher the OARSI score of cartilage. Moreover, the tibial plateau affected by alignment had more TRAP + osteoclasts, Osterix + osteoprogenitors, and osteocalcin + osteoblasts and fewer sclerostin + osteocytes. CONCLUSIONS: The variation of tibial plateau STB remodeling activity and microstructure was associated with HKA angle and cartilage degradation. Knee malalignment may cause abnormal STB remodeling and microstructural sclerosis, which may potentially affect load stress transmission from the cartilage to the STB, thus resulting in accelerated knee OA progression.
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Remodelação Óssea , Osso Esponjoso/patologia , Osteoartrite do Joelho/patologia , Idoso , Articulação do Tornozelo/diagnóstico por imagem , Cartilagem Articular , Estudos Transversais , Feminino , Articulação do Quadril/diagnóstico por imagem , Humanos , Articulação do Joelho/diagnóstico por imagem , Masculino , Pessoa de Meia-IdadeRESUMO
Emerging evidence indicates that bone mass is regulated by systemic energy balance. Temperature variations have profound effects on energy metabolism in animals, which will affect bone remodeling. But the mechanism remains unclear. 2-month-old C57BL/6J male mice were exposed to cold (4°C) and normal (23°C) temperatures for 28 days and the effects of cold exposure on bone mass was investigated. Micro-computed tomography results showed that bone volume fraction was significantly reduced after 14 days of exposure to cold temperature, and it was recovered after 28 days. Ploton silver staining and immunohistochemical results further revealed that exposure to cold decreased canalicular length, number of E11-and MMP13-positive osteocytes after 14 days, but they returned to the baseline levels after 28 days, different from the normal temperature control group. In addition, change of Caspase-3 indicated that exposure to cold temperature augmented apoptosis of osteocytes. In vitro results confirmed the positive effect of brown adipocytes on osteocyte's dendrites and E11 expression. In conclusion, our findings indicate that cold exposure can influence bone mass in a time-dependent manner, with bone mass decreasing and recovering at 2 and 4 weeks respectively. The change of bone mass may be caused by the apoptosis osteocytes. Brown adipocyte tissue could influence bone remodeling through affecting osteocyte.
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Cold temperature activates the sympathetic nervous system (SNS) to induce bone loss by altering bone remodeling. Brown adipose tissue (BAT) is influenced by the SNS in cold environments. Many studies have confirmed a positive relationship between BAT volume and bone mass, but the influence and mechanism of BAT on bone in vivo and in vitro is still unknown. Two-month-old C57/BL6j male mice were exposed to cold temperature (4°C) to induce BAT generation. BAT volume, bone remodeling and microstructure were assessed after 1 day, 14 days and 28 days of cold exposure. CTX-1, P1NP and IL-6 levels were detected in the serum by ELISA. To determine the effect of BAT on osteoclasts and osteoblasts in vitro, brown adipocyte conditional medium (BAT CM) was collected and added to the differentiation medium of bone marrow-derived macrophages (BMMs) and bone marrow mesenchymal stem cells (BMSCs). Micro-CT results showed that the bone volume fraction (BV/TV, %) significantly decreased after 14 days of exposure to cold temperature but recovered after 28 days. Double labeling and TRAP staining in vivo showed that bone remodeling was altered during cold exposure. BAT volume enlarged after 14 days of cold stimulation, and IL-6 increased. BAT CM promoted BMSC mineralization by increasing osteocalcin (Ocn), RUNX family transcription factor 2 (Runx2) and alkaline phosphatase (Alp) expression, while bone absorption was inhibited by BAT CM. In conclusion, restoration of bone volume after cold exposure may be attributed to enlarged BAT. BAT has a beneficial effect on bone mass by facilitating osteogenesis and suppressing osteoclastogenesis.
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Tecido Adiposo Marrom/metabolismo , Remodelação Óssea/fisiologia , Osso e Ossos/metabolismo , Temperatura Baixa , Colágeno Tipo I/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Fragmentos de Peptídeos/metabolismo , Peptídeos/metabolismo , Pró-Colágeno/metabolismo , Tecido Adiposo Marrom/patologia , Tecido Adiposo Marrom/fisiologia , Animais , Osso e Ossos/diagnóstico por imagem , Meios de Cultivo Condicionados , Macrófagos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Tamanho do Órgão , Osteogênese/fisiologia , Microtomografia por Raio-XRESUMO
BACKGROUND: Coronavirus disease 2019 (COVID-19) pandemic continues to spread across the world. Specimens of blood, body fluids and excreta received in the department of pathology undoubtedly increased the risk of infection, especially in some hospitals that are short of professional protection capability. Here we provided a new simple way for the sputum cytology test during the COVID-19 pandemic. METHODS: Sputum samples from 30 patients with lung cancer were collected and divided into two groups, including the control group and the experimental group. Samples of the control group were processed in the biological safety cabinet, while the experimental group was put into the sealed specimen bag directly and pretreated with 75% medical alcohol. Then the cell morphology and tumor cell identification were analyzed by cell smears and liquid-based cell staining. The expression of cell antigens was determined by immunohistochemical staining. RESULT: Our result showed that both sputum samples in two groups exhibited complete cell structure and clear morphology according to the cell smear and liquid-based cell staining. In addition, the immunohistochemical result showed that cell antigens, including cytokeratin (CK), leukocyte common antigen (LCA), and thyroid transcription factor-1 (TTF1), were specifically expressed in the cell membrane, cytoplasm, and nucleus, respectively. The tumor cells were distributed diffusely, and cell antigens were located accurately after pretreatment with 75% medical alcohol and were consistent with that of the control group. CONCLUSION: Using 75% medical alcohol to pretreat sputum specimens has no obvious impact on cell morphology and antigens expression. Our study provided a new method for the sputum cytology test with no direct contact so as to protect medical staff against the virus during COVID-19 outbreak.
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AIMS: Folliculogenesis contains gonadotropin-independent and -dependent stage. Disruption in any of this process would induce failure in retrieving capable oocytes during clinical treatment. However, there is still limited understanding of the molecular components specifically regulating this process. MATERIAL AND METHODS: Ovaries of P3, P20 and exogenous gonadotropin-treated P22 mice were sampled and underwent RNA-seq to investigate the transcriptome variance during mouse folliculogenesis. KEY FINDINGS: In our dataset, 1883 and 626 DEGs were captured for each stage respectively, which were further clustered into eight expression patterns. Pathway enrichment analysis identified distinct biological processes enriched in two stages, with the most prominent being the pathways related to metabolism, gene expression, cell cycle, immune system and DNA methylation. Transcriptional regulator inference yielded eight master transcription factors (i.e. Runx1, Stat3, Sox3, Pou5f1, Gata4, Foxl2, Cebpb, and Esr1) driving folliculogenesis. SIGNIFICANCE: Our study revealed the temporal transcriptional reprogramming and gene expression dynamics during folliculogenesis mediated by extra hormone treatment, which could provide novel insights to controlled ovarian stimulation in future infertility treatment.
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Hormônios/farmacologia , Folículo Ovariano/metabolismo , Transcrição Gênica , Animais , Bases de Dados Genéticas , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Camundongos Endogâmicos C57BL , Folículo Ovariano/efeitos dos fármacos , Fatores de Tempo , Fatores de Transcrição/metabolismo , Transcrição Gênica/efeitos dos fármacosRESUMO
Ptk2b has been found playing critical roles in oocyte maturation and subsequent fertilization in vitro. But what is the exact in vivo function in reproduction still elusive. Here, by constructing Ptk2b mutant mice, we found Ptk2b was not essential for mice fertility, unexpectedly, contrary to previously reported in vitro findings, we found Ptk2b ablation significantly improved female fecundity. Follicle counting indicated that the number of primordial follicles and growing follicles in matured mice was significantly increased in the absence of Ptk2b, whereas the primordial follicle formation showed no defects. We also found this regulation was in an autophosphorylation independent pathway, as autophosphorylation site mutant mice (PTK2BY402F ) show no phenotype in female fertility. Further biochemistry studies revealed that Ptk2b ablation promotes folliculogenesis via Erk pathway mediate follicle survival. Together, we found a novel biological function of Ptk2b in folliculogenesis, which could be potentially used as a therapeutic target for corresponding infertility.
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Fertilidade/genética , Quinase 2 de Adesão Focal/genética , Oócitos/crescimento & desenvolvimento , Folículo Ovariano/crescimento & desenvolvimento , Animais , Feminino , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Oócitos/metabolismo , Folículo Ovariano/metabolismo , Fosforilação/genéticaRESUMO
PURPOSE: Bone remodeling is affected by mechanical stimulation. Osteocytes are the primary mechanical load-sensing cells in the bone, and can regulate osteoblast and osteoclast activity, thus playing a key role in bone remodeling. Further, bone mass during exercise is also regulated by Leukemia inhibitory factor (LIF). This study aimed to investigate the role of LIF in the mechanical response of the bone, in vivo and in vitro, and to elucidate the mechanism by which osteocytes secrete LIF to regulate osteoblasts and osteoclasts. METHODS: A tail-suspension (TS) mouse model was used in this study to mimic muscular disuse. ELISA and immunohistochemistry were performed to detect bone and serum LIF levels. Micro-computed tomography (CT) of the mouse femurs was performed to measure three-dimensional bone structure parameters. Fluid shear stress (FSS) and microgravity simulation experiments were performed to study mechanical stress-induced LIF secretion and its resultant effects. Bone marrow macrophages (BMMs) and bone mesenchymal stem cells (BMSCs) were cultured to induce in vitro osteoclastogenesis and osteogenesis, respectively. RESULTS: Micro-CT results showed that TS mice exhibited deteriorated bone microstructure and lower serum LIF expression. LIF secretion by osteocytes was promoted by FSS and was repressed in a microgravity environment. Further experiments showed that LIF could elevate the tartrate-resistant acid phosphatase activity in BMM-derived osteoclasts through the STAT3 signaling pathway. LIF also enhanced alkaline phosphatase staining and osteogenesis-related gene expression during the osteogenic differentiation of BMSCs. CONCLUSION: Mechanical loading affected LIF expression levels in osteocytes, thereby altering the balance between osteoclastogenesis and osteogenesis.
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BACKGROUND: CYP1B1 is recognized as a valuable target for chemotherapy. It catalyzes the bioactivation of naphthoquinone oximes within certain cancer cell lines. However, the expression level of CYP1B1 in melanoma and the functional role regulating the activity of DMAKO-20 as a representative naphthoquinone oxime against skin carcinoma is still unknown. OBJECTIVE: We sought to examine the expression level of CYP1B1 in melanoma and explore the molecular mechanism behind the anticancer effects of DMAKO-20 in melanoma. METHODS: CYP1B1 expression levels in paraffin specimens taken from melanoma patients, and its expression levels in B16/F10 cancer cells were investigated using immunohistochemical staining. The molecular mechanisms behind DMAKO20 activity against melanoma was investigated by using cytotoxicity, cell scratching, apoptotic, and immunoblotting assays. RESULTS: CYP1B1, the P450 isoform was expressed at high levels in melanoma tissues and cultured B16/F10 cells, but was undetectable in normal tissues or fibroblasts. In cell proliferation assays, the shikonin oxime DMAKO-20 exhibited potent and selective antiproliferative effects against B16/F10 melanoma cells and inhibited migration. Several mechanisms for the anticancer effects of DMAKO-20 have been identified in B16/F10 melanoma cells, including apoptosis, upregulation of mitochondrial apoptotic Bax proteins and downregulation of anti-apoptotic Bcl-2. The results from these mechanistic investigations indicated that DMAKO-20 underwent CYP1B1-mediated metabolic activation to activate anticancer metabolites within melanoma cells. CONCLUSION: DMAKO-20 exhibited a selective cytotoxic effect on melanoma cells through CYP1B1-mediated activation. Using DMAKO-20 as a lead compound, further structural optimization may provide new drug entities for the treatments of malignant skin carcinomas.
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BACKGROUND: Knee osteoarthritis (OA) is a common disabling disease involving the entire joint tissue, and its onset and progression are affected by many factors. However, the current number of studies investigating the relationship between subchondral trabecular bone (STB), knee alignment, and OA severity is limited. We aimed to investigate the variation in tibial plateau STB microarchitecture in end-stage knee OA patients and their association with knee alignment (hip-knee-ankle, HKA, angle) and OA severity. METHODS: Seventy-one knee OA patients scheduled for total knee arthroplasty (TKA) underwent preoperative radiography to measure the HKA angle and Kellgren-Lawrence grade. Tibial plateaus collected from TKA were scanned using micro-computed tomography to analyze the STB microarchitecture. Histological sections were used to assess cartilage degeneration (OARSI score). Correlations between the HKA angle, OA severity (OARSI score, Kellgren-Lawrence grade), and STB microarchitecture were evaluated. Differences in STB microstructural parameters between varus and valgus alignment groups based on the HKA angle were examined. RESULTS: The HKA angle was significantly correlated with all STB microarchitecture parameters (p < 0.01). The HKA angle was more correlated with the medial-to-lateral ratios of the microarchitecture parameters than with the medial or lateral tibia plateaus. The HKA angle and all STB microarchitecture parameters are significantly correlated with both the OARSI score and Kellgren-Lawrence grade (p < 0.01). CONCLUSIONS: The STB microarchitecture is associated with the HKA angle and OA severity. With the increase of the knee alignment deviation and OA severity, the STB of the affected side tibial plateau increased in bone volume, trabecular number, and trabecular thickness and decreased in trabecular separation.