Genkwanin alleviates intervertebral disc degeneration via regulating ITGA2/PI3K/AKT pathway and inhibiting apoptosis and senescence

Intervertebral disc degeneration (IVDD) is a progressive degenerative disease influenced by various factors. Genkwanin, a known anti-inflammatory flavonoid, has not been explored for its potential in IVDD management. This study aims to investigate the effects and mechanisms of genkwanin on IVDD. In vitro, cell experiments revealed that genkwanin dose-dependently inhibited Interleukin-1β-induced expression levels of inflammatory factors (Interleukin-6, inducible nitric oxide synthase, cyclooxygenase-2) and degradation metabolic protein (matrix metalloproteinase-13). Concurrently, genkwanin upregulated the expression of synthetic metabolism genes (type II collagen, aggrecan). Moreover, genkwanin effectively reduced the phosphorylation of phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin, mitogen-activated protein kinase (MAPK), and nuclear factor-κB (NF-κB) pathways. Transcriptome sequencing analysis identified integrin α2 (ITGA2) as a potential target of genkwanin, and silencing ITGA2 reversed the activation of PI3K/AKT pathway induced by Interleukin-1β. Furthermore, genkwanin alleviated Interleukin-1β-induced senescence and apoptosis in nucleus pulposus cells. In vivo animal experiments demonstrated that genkwanin mitigated the progression of IVDD in the rat model through imaging and histological examinations. In conclusion, This study suggest that genkwanin inhibits inflammation in nucleus pulposus cells, promotes extracellular matrix remodeling, suppresses cellular senescence and apoptosis, through the ITGA2/PI3K/AKT, NF-κB and MAPK signaling pathways. These findings indicate that genkwanin may be a promising therapeutic candidate for IVDD.

Microstructural, Micromechanical Atlas of the Temporomandibular Joint Disc

The temporomandibular joint (TMJ) disc is mainly composed of collagen, with its arrangement responding to efficient stress distribution. However, microstructural and micromechanical transformations of the TMJ disc under resting, functional, and pathological conditions remain unclear. To address this, our study presents a high-resolution microstructural and mechanical atlas of the porcine TMJ disc. First, the naive microstructure and mechanical properties were investigated in porcine TMJ discs (resting and functional conditions). Subsequently, the perforation and tear models (pathological conditions) were compared. Following this, a rabbit model of anterior disc displacement (abnormal stress) was studied. Results show diverse microstructures and mechanical properties at the nanometer to micrometer scale. In the functional state, gradual unfolding of the crimping cycle in secondary and tertiary structures leads to D-cycle prolongation in the primary structure, causing tissue failure. Pathological conditions lead to stress concentration near the injury site due to collagen interfibrillar traffic patterns, resulting in earlier damage manifestation. Additionally, the abnormal stress model shows collagen damage initiating at the primary structure and extending to the superstructure over time. These findings highlight collagen's various roles in different pathophysiological states. Our study offers valuable insights into TMJ disc function and dysfunction, aiding the development of diagnostic and therapeutic strategies for TMJ disorders, as well as providing guidance for the design of structural biomimetic materials.

CXCL chemokines-mediated communication between macrophages and BMSCs on titanium surface promotes osteogenesis via the actin cytoskeleton pathway

The refined functional cell subtypes in the immune microenvironment of specific titanium (Ti) surface and their collaborative role in promoting bone marrow mesenchymal stem cells (BMSCs) driven bone integration need to be comprehensively characterized. This study employed a simplified co-culture system to investigate the dynamic, temporal crosstalk between macrophages and BMSCs on the Ti surface. The M2-like sub-phenotype of macrophages, characterized by secretion of CXCL chemokines, emerges as a crucial mediator for promoting BMSC osteogenic differentiation and bone integration in the Ti surface microenvironment. Importantly, these two cells maintain their distinct functional phenotypes through a mutually regulatory interplay. The secretion of CXCL3, CXCL6, and CXCL14 by M2-like macrophages plays a pivotal role. The process activates CXCR2 and CCR1 receptors, triggering downstream regulatory effects on the actin cytoskeleton pathway within BMSCs, ultimately fostering osteogenic differentiation. Reciprocally, BMSCs secrete pleiotrophin (PTN), a key player in regulating macrophage differentiation. This secretion maintains the M2-like phenotype via the Sdc3 receptor-mediated cell adhesion molecules pathway. Our findings provide a novel insight into the intricate communication and mutual regulatory mechanisms operating between BMSCs and macrophages on the Ti surface, highlight specific molecular events governing cell-cell interactions in the osteointegration, inform the surface design of orthopedic implants, and advance our understanding of osteointegration.

[Clinical application of retrosigmoid approach for BONEBRIDGE implantation after auricle reconstruction using expanded postauricular flap]

Objective: To explore the safety and reliability of retrosigmoid approach BONEBRIDGE implantation in patients with auricle reconstruction using skin expansion flap. Methods: A retrospective analysis was conducted on 43 congenital aural atresia cases (43 ears) who underwent BONEBRIDGE implantation from September 2019 to January 2023 in Beijing Tongren Hospital. 30 males and 13 females were included in this work. The implantation age was 9-36 years old (median age=10 y/o). All cases underwent auricle reconstruction surgery using the posterior ear flap expansion method, with 36 cases using the single expanded postauricular flap method and 7 cases using two-flap method. BONEBRIDGE implant surgery was performed during the third stage of auricle reconstruction or after all stages. The hearing improvements were evaluated by comparing the changes in pure tone hearing threshold and speech recognition rate of patients before and after BONEBRIDGE implantation. Routine follow-up was conducted to observe the hearing results and complications. SPSS 14.0 software was applied for data statistical analysis. Results: All 43 patients healed well and had no surgical complications when discharge. The average bone conduction hearing threshold after surgery was (8.2±6.6) dBHL, and there was no statistically significant difference compared to the preoperative [(8.1±5.7) dBHL] (P=0.95). After surgery, the threshold of hearing assistance with power on was significantly lower than that without hearing assistance [(32.8±4.6) dBHL vs (60.5±5.5) dBHL], and the difference was statistically significant (P<0.001). The speech recognition rate of monosyllable words, disyllabic words and short sentences in quiet environment increased to 72%, 84%, and 98% respectively. The differences were statistically significant (P<0.001). The speech recognition rate of monosyllabic words, disyllabic words, and short sentences in noise environment was significantly increased by 70%, 80%, and 92% respectively (P<0.001). After a follow-up of 4 to 47 months (median=24 months), the hearing results were stable and the aesthetic outcomes were satisfying. One patient had delayed hematoma around coil of the implant. After aspiration and compressed dressing for one week, hematoma was not recurrent. Conclusion: For patients after auricle reconstruction using expanded postauricular flap, the preference of retrosigmoid approach is a good choice in terms of safety and reliability of operation, as well as aesthetic appearance.

First Measurement of the Nuclear-Recoil Ionization Yield in Silicon at 100 eV

We measured the nuclear-recoil ionization yield in silicon with a cryogenic phonon-sensitive gram-scale detector. Neutrons from a monoenergetic beam scatter off of the silicon nuclei at angles corresponding to energy depositions from 4 keV down to 100 eV, the lowest energy probed so far. The results show no sign of an ionization production threshold above 100 eV. These results call for further investigation of the ionization yield theory and a comprehensive determination of the detector response function at energies below the keV scale.

Nucleic acid direct delivery to fibroblasts: a review of nucleofection and applications

The fibroblast is one of the ideal target cell candidates for cell-based gene therapy approaches to promote tissue repair. Gene delivery to fibroblasts by viral transfection has been confirmed to have high transfection efficiency. However, in addition to immunogenic effects of viruses, the random integration of viral genes may damage the genome, affect the cell phenotype or even cause cancerous mutations in the transfected cells. Due to these potential biohazards and unknown long-term risks, the clinical use of viral transfection has been very limited. In contrast, initial non-viral transfection methods have been simple and safe to implement, with low immunogenicity, insertional mutagenesis, and risk of carcinogenesis, but their transfection efficiency has been relatively low. Nucleofection, a more recent non-viral transfection method, now combines the advantages of high transfection efficiency and direct nucleic acid delivery to the nucleus with a high safety.Here, we reviewed recent articles on fibroblast nucleofection, summarized different research points, improved methods and application scopes, and opened up ideas for promoting the further improvement and development of fibroblast nucleofection to meet the needs of a variety of disease research and clinical applications.

The role of Ca2+ /Calcineurin/NFAT signalling pathway in osteoblastogenesis

The bone remodelling process is closely related to bone health. Osteoblasts and osteoclasts participate in the bone remodelling process under the regulation of various factors inside and outside. Excessive activation of osteoclasts or lack of function of osteoblasts will cause occurrence and development of multiple bone‐related diseases. Ca²⁺/Calcineurin/NFAT signalling pathway regulates the growth and development of many types of cells, such as cardiomyocyte differentiation, angiogenesis, chondrogenesis, myogenesis, bone development and regeneration, etc. Some evidences indicate that this signalling pathway plays an extremely important role in bone formation and bone pathophysiologic changes. This review discusses the role of Ca²⁺/Calcineurin/NFAT signalling pathway in the process of osteogenic differentiation, as well as the influence of regulating each component in this signalling pathway on the differentiation and function of osteoblasts, whereby the relationship between Ca²⁺/Calcineurin/NFAT signalling pathway and osteoblastogenesis could be deeper understood.

[Evaluation of adhesive bone conduction hearing aid in pediatric patients with unilateral congenital aural atresia]

Objective: To evaluate the auditory efficacy and subjective satisfaction of adhesive bone conduction hearing aid in children with unilateral congenital aural atresia (UCAA). Methods: Ten subjects (5 males and 5 females) diagnosed with UCAA with an average age of 8.3 years old (ranged from 5 to 15) were included in Beijing Tongren Hospital, Capital Medical University from January to August 2019. The free sound field hearing threshold, word recognition score in quiet, speech reception threshold in noise and sound localization ability (results were measured by RMS error) tests were performed in unaided and aided situation, respectively. Subjective satisfaction questionnaires were also distributed to subjects. Paired t test and Wilcoxon signed rank test were used as statistical analysis methods. Results: The average hearing threshold in aided condition was improved by (21.9±4.4) dB (t=15.8，P<0.05). Speech recognition abilities were generally improved both under quiet and noise (P<0.05);however, when the binaural summation, squelch and head shadow effects were analyzed respectively, the binaural squelch effect was not statistically improved (P>0.05), while the other effects were improved in aided condition (P<0.05). In sound localization test, there was no significant difference of the RMS error value between the unaided and aided situation (P>0.05). The subjects got high satisfaction rates in three subjective questionnaires. Conclusion: The adhesive bone conduction hearing aid can provide significant audiological benefit for children with UCAA as well as raising the quality of their life.

Constraints on Lightly Ionizing Particles from CDMSlite

The Cryogenic Dark Matter Search low ionization threshold experiment (CDMSlite) achieved efficient detection of very small recoil energies in its germanium target, resulting in sensitivity to lightly ionizing particles (LIPs) in a previously unexplored region of charge, mass, and velocity parameter space. We report first direct-detection limits calculated using the optimum interval method on the vertical intensity of cosmogenically produced LIPs with an electric charge smaller than e/(3×10^{5}), as well as the strongest limits for charge ≤e/160, with a minimum vertical intensity of 1.36×10^{-7}  cm^{-2} s^{-1} sr^{-1} at charge e/160. These results apply over a wide range of LIP masses (5  MeV/c^{2} to 100  TeV/c^{2}) and cover a wide range of βγ values (0.1-10^{6}), thus excluding nonrelativistic LIPs with βγ as small as 0.1 for the first time.

Light Dark Matter Search with a High-Resolution Athermal Phonon Detector Operated above Ground

We present limits on spin-independent dark matter-nucleon interactions using a 10.6 g Si athermal phonon detector with a baseline energy resolution of σ_{E}=3.86±0.04(stat)_{-0.00}^{+0.19}(syst)  eV. This exclusion analysis sets the most stringent dark matter-nucleon scattering cross-section limits achieved by a cryogenic detector for dark matter particle masses from 93 to 140  MeV/c^{2}, with a raw exposure of 9.9 g d acquired at an above-ground facility. This work illustrates the scientific potential of detectors with athermal phonon sensors with eV-scale energy resolution for future dark matter searches.

CircRNA_103801 accelerates proliferation of osteosarcoma cells by sponging miR-338-3p and regulating HIF-1/Rap1/PI3K-Akt pathway

This study aimed to investigate the roles of hsa_circRNA_103801 in the progression of osteosarcoma (OS) cells. Quantitative reverse transcription-polymerase chain reaction (RT-qPCR) was used to detect the expression level of circRNA_103801 in OS cells. Cell count kit-8 and Transwell migration and invasion assays were employed to detect the proliferation, migration, and invasion abilities of OS cells. The effects of circRNA_103801 on the apoptosis of OS cells were identified by flow cytometry. The binding relationship between circRNA_103801 and miR-338-3p was verified by bioinformatics analysis. MiR-338-3p level in OS cell lines was detected by RT-qPCR. Additionally, Western blotting was utilized to detect the expression levels of HIF-1, Rap1, PI3K, and Akt in OS cells. The results showed that the expression level of circRNA_103801 was significantly up-regulated in OS patients' tissues. Inhibiting the expression level of circRNA_103801 could attenuate the proliferation, migration, and invasion abilities of OS cells. In addition, the down-regulated expression level of circRNA_103801 could induce cell apoptosis. The results of the luciferase reporter assay suggested that circRNA_103801 could be combined with miR-338-3p, and the RT-qPCR revealed that the miR-338-3p level in OS cells after knockdown of circRNA_103801 was elevated compared with the control group. The results of Western blotting suggested that the expression levels of HIF-1, Rap1, PI3K, and Akt were elevated in OS cells. In conclusion, the circRNA_103801-miR-3388-3p-HIF-1/Rap1/PI3K-Akt pathway could be a therapeutic target of OS.

Metabolomic profile of milk fermented with Streptococcus thermophilus cocultured with Bifidobacterium animalis ssp. lactis, Lactiplantibacillus plantarum, or both during storage

In this study, the microbial interactions among cocultures of Streptococcus thermophilus (St) with potential probiotics of Bifidobacterium animalis ssp. lactis (Ba) and Lactiplantibacillus plantarum (Lp) in fermented milk were investigated during a storage period of 21 d at 4°C, in terms of acidifying activity (pH and titratable acidity), viable counts, and metabolites. A nontargeted metabolomics approach based on ultra-high-performance liquid chromatography coupled with mass spectrometry was employed for mapping the global metabolite profiles of fermented milk. Probiotic strains cocultured with St accelerated milk acidification, and improved the microbial viability compared with the single culture of St. The St-Ba/Lp treatment manifested a higher bacteria viability and acidification ability in comparison with the St-Ba or the St-Lp treatment. Relative quantitation of 179 significant metabolites was identified, including nucleosides, AA, short peptides, organic acids, lipid derivatives, carbohydrates, carbonyl compounds, and compounds related to energy metabolism. The principal component analysis indicated that St treatment and coculture treatments displayed a complete distinction in metabolite profiles, and Lp had a larger effect than Ba on metabolic profiles of fermented milk produced by cofermentation with St during storage. The heat map in combination with hierarchical cluster analysis showed that the abundance of metabolites significantly varied with the starter cultures over the storage, and high abundance of metabolites was observed in either St or coculture samples. The St-Ba/Lp treatment showed relatively high abundance for the vast majority of metabolites. These findings suggest that the profile of the metabolites characterizing fermented milk samples may depend on the starter cultures, and incorporation of probiotics may considerably influence the metabolomic activities of fermented milks.

[Bonebridge implantation combined with simultaneous bilateral auricle reconstruction for bilateral congenital aural atresia]

Objective: To investigate the feasibility and safety of auricle reconstruction combined with Bonebridge implantation for bilateral aural atresia patients. Methods: A retrospective analysis was conducted for 36 cases(72 ears) who underwent Bonebridge implantation combined with bilateral auricle reconstruction from February 1, 2017 to January 15, 2020. All cases were bilateral congenital aural atresia and underwent Nagata auricle reconstruction for both sides simultaneously. Bonebridge implantations were performed during the second stage of auricle reconstruction. Results: All 36 patients healed well and had no surgical complications when discharged. The preoperative average bone conduction threshold of the patients was(8.5±5.8) dB HL and postoperative bone conduction threshold was (8.4±5.2) dB HL. There was no significant change after the implantation (P=0.724). The preoperative average air conduction threshold of was(64.9±7.4)dB HL and postoperative air conduction threshold was (24.0±5.3) dB HL, which had a significant change after the implantation (P<0.001). The hearing threshold with Bonebridge significantly decreased by 40.9 dB HL compared with the preoperative air conduction threshold(P<0.001). The speech recognition rate of monosyllable words, disyllabic words and short sentences in quiet environment increased by 62.5%, 63.5% and 72.2% respectively. The differences were statistically significant (P<0.001). The speech recognition rate of monosyllabic words, disyllabic words and short sentences in noise environment were significantly increased by 55.9%, 58.9% and 69.9% respectively (P<0.001). After a follow-up of 18.3 months in average, the hearing results were stable and the aesthetic outcomes were satisfied. One patient had implant rupture and healed after revision surgery. Conclusions: With an integrated surgical procedure, patients with bilateral congenital aural atresia can complete bilateral auricle reconstruction and hearing implantation within six months. This integrated surgical procedure is safe and efficient, with a stable hearing improvement and good appearance.

PERK signaling pathway in bone metabolism: Friend or foe?

Osteoblasts and osteoclasts participate in the process of bone remodelling to meet the needs of normal growth and development or repair pathological damage. Endoplasmic reticulum stress (ER stress) can break the intracellular homeostasis of osteoclasts and osteoblasts, which is closely related to abnormal bone remodelling. The double‐stranded RNA‐dependent protein kinase (PKR)‐like ER kinase (PERK) is a key transmembrane protein that regulates ER stress, and growing evidence suggests that the PERK pathway plays a crucial role in regulating bone metabolism under both physiological and pathological conditions. Based on the current findings, we summarized the main mechanisms involved in bone metabolism downstream of the PERK pathway, among which elF2α, FOXO1, CaN, Nrf2 and DAG play a role in regulating the differentiation of osteoblasts and osteoclasts. Importantly, strategies by the regulation of PERK pathway exert beneficial effects in preclinical trials of several bone‐related diseases. Given the importance and novelty of PERK pathway, we provide an overview and discuss the roles of PERK pathway in regulating bone metabolism and its impact on bone‐related diseases. We hope that the development of research in this field will bring a bright future for the treatment of bone‐related diseases.

MiR-135b-5p affected malignant behaviors of ovarian cancer cells by targeting KDM5B

The article "MiR-135b-5p affected malignant behaviors of ovarian cancer cells by targeting KDM5B, by R. Ren, J. Wu, M.-Y. Zhou, published in Eur Rev Med Pharmacol Sci 2020; 24 (7): 3548-3554-DOI: 10.26355/eurrev_202004_20815-PMID: 32329828" has been withdrawn from the authors stating that "some data cannot be repeated by our further research". The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/20815.

[CT imaging analysis of 33 cases with the 2019 novel coronavirus infection]

Objective: To explore the CT imaging features of the 2019 novel coronavirus (2019-nCoV) infection in order to summarize the imaging characteristics of the disease and improve the ability of imaging diagnosis and early diagnosis of the disease. Methods: From January 13, 2020 to January 31, 2020, a total of 33 patients with 2019-nCoV infection diagnosed and treated by Suzhou Fifth People's Hospital were analyzed retrospectively, including 20 males and 13 females, with an average age of (50±12) years, ranging from 20 to 70 years old. There were 3 cases of mild type, 27 cases of common type and 3 cases of severe type.There were 2 cases with hypertension, 1 case with postoperative lung,1 case with diabetes, 1 case with chronic bronchitis, and 1 case with bronchiectasis.SPSS25.0 Chi-square test was used to analyze the distribution of lesions in each lung lobe; SPSS25.0 Spearman correlation coefficient was used to analyze the image score and clinical classification. Results: There were 3 cases (9.1%) with normal lung and 30 cases (90.9%) with Novel Coronavirus Pneumonia(COVID-19) of the 2019-nCoV infected patients. In the distribution of COVID-19, 29 cases (87.9%) were involved in bilateral lung and 1 case (3.0%) in unilateral lung. There was no statistically significant difference in the distribution of lesions in each lobe. The correlation coefficient between the degree of lesion distribution and clinical classification was 0.819, and the two were highly correlated.There were 30 cases (90.9%) with subpleural lesions, 17 cases (51.5%) with central lesions. There were many kinds of lesions, 25 cases (75.8%) had ground glass density shadow, 16 cases (48.5%) had consolidation, 12 cases (36.4%) had interstitial change, and 18 cases (54.5%) had interlobular septal thickening. Among the 22 cases, 10 cases had more lesions, 6 cases had no changes and 6 cases had less lesions. Conclusion: Most of the patients with 2019-nCoV infection have pulmonary inflammation.CT manifestations include multiple parts, subpleural area or middle and lateral field of lung, ground glass shadow and consolidation, or coexistence. Some cases have pleural thickening or interlobular septal thickening. CT images can indicate the diagnosis of COVID-19 and provide important basis for early detection and disease monitoring.

Improved Immunoregulation of Ultra-Low-Dose Silver Nanoparticle-Loaded TiO2 Nanotubes via M2 Macrophage Polarization by Regulating GLUT1 and Autophagy

Introduction

The bone regeneration of endosseous implanted biomaterials is often impaired by the host immune response, especially macrophage-related inflammation which plays an important role in the bone healing process. Thus, it is a promising strategy to design an osteo-immunomodulatory biomaterial to take advantage of the macrophage-related immune response and improve the osseointegration performance of the implant.

Methods

In this study, we developed an antibacterial silver nanoparticle-loaded TiO₂ nanotubes (Ag@TiO₂-NTs) using an electrochemical anodization method to make the surface modification and investigated the influences of Ag@TiO₂-NTs on the macrophage polarization, osteo-immune microenvironment as well as its potential molecular mechanisms in vitro and in vivo.

Results

The results showed that Ag@TiO₂-NTs with controlled releasing of ultra-low-dose Ag⁺ ions had the excellent ability to induce the macrophage polarization towards the M2 phenotype and create a suitable osteo-immune microenvironment in vitro, via inhibiting PI3K/Akt, suppressing the downstream effector GLUT1, and activating autophagy. Moreover, Ag@TiO₂-NTs surface could improve bone formation, suppress inflammation, and promote osteo-immune microenvironment compared to the TiO₂-NTs and polished Ti surfaces in vivo. These findings suggested that Ag@TiO₂-NTs with controlled releasing of ultra-low-dose Ag⁺ ions could not only inhibit the inflammation process but also promote the bone healing by inducing healing-associated M2 polarization.

Discussion

Using this surface modification strategy to modulate the macrophage-related immune response, rather than prevent the host response, maybe a promising strategy for implant surgeries in the future.

PKM2 suppresses osteogenesis and facilitates adipogenesis by regulating β-catenin signaling and mitochondrial fusion and fission

Bone marrow mesenchymal stem cells (BMSCs) differentiation dysfunction is a common pathological phenotype of several prevalent metabolic and genetic bone diseases. Pyruvate kinase muscle isoenzyme 2 (PKM2) regulates the last step of glycolysis, and its role in BMSCs differentiation is still unknown. In this study, the influence of PKM2 on osteogenesis and adipogenesis was assessed in vitro and in vivo. We found that DASA-58 (the activator of PKM2) reduced the enzymatic activity of ALP, and inhibited the levels of osteogenic marker genes, especially RUNX2, which is a crucial transcription factor for osteogenesis. Besides, we provided evidence that C3k, an inhibitor of PKM2, caused increase in mitochondrial membrane potential and maintained low levels of ROS, and promoted mitochondrial fusion. Furthermore, after treatment with DASA-58, the level of active β-catenin gradually decreased, which also inhibited the transport of active β-catenin into the nucleus, but C3k obviously promoted its nuclear translocation. As for adipogenesis, PKM2 activation increased the expression of adipogenic related genes and decreased active-β-catenin expression, whereas treatment of C3k had the opposite effect. In addition, C3k significantly attenuated ovariectomy-induced trabecular bone loss in vivo. Our findings helped uncover the molecular mechanisms underlying PKM2 regulation of BMSCs differentiation.

PKM2 regulates angiogenesis of VR-EPCs through modulating glycolysis, mitochondrial fission, and fusion

Vascular resident endothelial progenitor cells (VR-EPCs) have a certain ability to differentiate into endothelial cells (ECs) and participate in the process of angiogenesis. Glycolysis and mitochondrial fission and fusion play a pivotal role in angiogenesis. Pyruvate kinase muscle isoenzyme 2 (PKM2), which mediates energy metabolism and mitochondrial morphology, is regarded as the focus of VR-EPCs angiogenesis in our study. VR-EPCs were isolated from the hearts of 12-weeks-old Sprague-Dawley rats. The role of PKM2 on angiogenesis was evaluated by tube formation assay, wound healing assay, transwell assay, and chick chorioallantoic membrane assay. Western blot analysis, flow cytometry, mitochondrial membrane potential detection, reactive oxygen species (ROS) detection, immunofluorescence staining, and quantitative real-time polymerase chain reaction were used to investigate the potential mechanism of PKM2 for regulating VR-EPCs angiogenesis. We explored the function of PKM2 on the angiogenesis of VR-EPCs. DASA-58 (the activator of PKM2) promoted VR-EPCs proliferation and PKM2 activity, it also could promote angiogenic differentiation. At the same time, DASA-58 significantly enhanced glycolysis, mitochondrial fusion, slightly increased mitochondrial membrane potential, and maintained ROS at a low level. C3k, an inhibitor of PKM2, inhibited PKM2 activity, expression of angiogenesis-related genes and tube formation. Besides, C3k drastically reduced glycolysis and mitochondrial membrane potential while significantly promoting mitochondrial fission and ROS level. Activation of PKM2 could promote VR-EPCs angiogenesis through modulating glycolysis, mitochondrial fission and fusion. By contrast, PKM2 inhibitor has opposite effects.

[Follow-up study on natural course changes of obstructive sleep apnea hypopnea syndrome among young and middle aged patients]

Objective: To explore the natural course of obstructive sleep apnea-hypopnea syndrome (OSAHS) and its associated factors in young and middle-aged patients with OSAHS. Methods: A total of 52 young and middle-aged OSAHS patients were recruited in this study from West China Hospital of Sichuan University. All patients were performed twice overnight polysomnography (PSG) examinations. At the baseline, patients underwent the first PSG and clinical evaluation from September 2009 to September 2017 and the patients received the second PSG from January 2017 to January 2019. During the follow-up period, these patients had no treatment. All patients were categorized into two groups including mild-to-moderate [5/h≤ apnea-hypopnea index (AHI)<30/h] group and severe (AHI ≥ 30/h) group according to the baseline AHI value. Differences in the clinical characteristics and PSG variables between baseline and follow-up were compared in two groups separately using t-tests or Mann-Whitney U test. The general linear correlation analysis was used to explore the factors related to the severity of OSAHS including AHI, the mean oxyhemoglobin saturation and the minimal oxyhemoglobin saturation during the follow-up period. Results: This study recruited 28 OSAHS patients in mild-to-moderate group [mean age, (39.7±10.2) y] and 24 patients in severe group [mean age, (41.0±7.1) y]. Compared to the baseline, there was a significant increase in AHI value [(45.0±25.3) vs (33.6±27.3)/h, P<0.001] in all OSAHS patients. Notably, the increase of AHI was more significant in the mild-to-moderate OSAHS group [(32.1±22.2) vs (13.6±8.7)/h, P<0.05] but not in severe OSAHS patients [(60.7±19.5) vs (58.0±21.5)/h, P>0.05]. A person correlation analysis revealed that the AHI value was positively related to the age (r=0.531, P=0.004) in mild-to-moderate OSAHS patients. Conclusion: The severity of OSAHS is increased with the age in young and middle-aged patients with mild-to-moderate OSAHS, but not in those with severe OSAHS.

[Associations between objective sleepiness and cognition function before and after CPAP in obstructive sleep apnea patients]

Objective: To examine the association between objective sleepiness and neurocognitive function before and after continuous positive airway pressure (CPAP) in obstructive sleep apnea (OSA) patients. Methods: A total of 53 patients with overnight polysomnography (PSG) determined moderate-to-severe OSA (apnea hypopnea index (AHI) ≥15 events/h) and with overnight CPAP therapy from West China Hospital, Sichuan University within the period from Feb 2018 to Dec 2018 were enrolled in the study. At the baseline, all patients underwent overnight PSG study, multiple sleep latency test (MSLT), psychomotor vigilance test (PVT), and Epworth sleepiness score (ESS). After CPAP therapy, all patients underwent MSLT and PVT. Paired nonparametric test or t test were used to compare the differences between daytime sleepiness and PVT performance before and after CPAP. Results: Compared with baseline data, AHI [68.8(42.2, 80.0) vs 7.4(3.1, 11.1) events/h, P<0.05] decreased, the percentages of non-rapid eye movement stage 3 sleep time [0(0, 0.5%) vs 4.4%(1.9%, 11.3%), P<0.05] and the percentages of rapid eye movement sleep time [18.6%(13.2%, 22.7%) vs 25.4%(23.85, 30.3%), P<0.05] increased after CPAP therapy. The reaction time (RT) [353.0(317.5, 429.5) vs 333.6(309.7, 381.4) ms, P<0.05], the slowest 10% RT [602.9(473.2, 841.3) vs 505.5(431.6, 618.8) ms, P<0.05] and the fastest 10% RT [260.8(236.6, 300.6) vs 251.4(233.6, 283.2) ms, P<0.05] shortened, and the lapse [6.0(2.5, 16.5) vs 3.0(1.0, 8.5) events, P<0.05] decreased. The mean sleep latency (MSL) [5.8 (3.4, 8.3) vs 7.5(4.7, 12.4) min, P<0.05] increased. The changes in PVT parameters [ΔRT (r=0.20, P>0.05), Δslowest 10% RT (r=0.15, P>0.05), Δfastest 10% RT (r=0.24, P>0.05), and Δlapse (r=0.15, P>0.05)] were not correlated with the change in MSL. The significant association between the slowest 10% RT and ESS was found in baseline data. Conclusions: The change in MSL is not associated with the change in PVT performance before and after CPAP therapy. MSLT and PVT may be different in nature.

[Association between mixed sleep apnea and treatment-emergent central sleep apnea]

Objective: To examine the association between mixed sleep apnea (MA) and treatment-emergent central sleep apnea (TE-CSA). Methods: A total of 256 patients meeting the diagnostic criteria of moderate to severe obstructive sleep apnea (OSA) based on overnight polysomnography (PSG) and receiving continuous positive airway pressure (CPAP) therapy in West China Hospital, Sichuan University during the period from August 2013 to November 2018 were enrolled in the study. Based on the mixed apnea index (MAI) and apnea-hypopnea index (AHI) in the baseline PSG study during non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep, the subjects were categorized into three groups of A (MAI=0/h, n=110), B (NREM-MAI≥5/h and REM-MAI<5/h, n=72) and C (REM-MAI≥5/h and NREM-MAI< 5/h, n=74). Sleep and breathing related parameters before and after CPAP therapy among three groups and the difference of TE-CSA incidence were analyzed. Results: The AHI [(44.2(26.8,64.5)/h,66.6(56.0,81.7)/h, 79.8(63.6, 88.3)/h], REM-AHI [50.0(34.7, 64.7)/h, 60.1(49.1, 70.0)/h, 66.3(56.1, 74.6)/h] and NREM-AHI[43.5(25.9, 65.1)/h,67.6(53.7, 82.4)/h,81.3(64.2, 91.5)/h]) were higher in group B and C compared to group A (all P<0.05),while the mean and lowest oxygen saturation [(92.6%±3.5%),(90.8%±3.6%),(87.3%±5.1%) and (70.6%±14.1%), (61.0%±16.0%), (47.9%±17.0%)] were lower in group B and group C compared to group A (all P<0.05). The incidence of TE-CSA after initial CPAP was 7.8% in all patients, and the incidence was significantly higher in group B of 14.1% compared to group C of 4.1% and group A of 2.7% (all P<0.05). Conclusions: TE-CSA is correlated with baseline MA, and baseline MA in NREM sleep can predict the incidence of TE-CSA after initial CPAP.

miRNA-138 regulates MLK3/JNK/MAPK pathway to protect BV-2 cells from H2O2-induced apoptosis

BACKGROUND

miR-138 is one of the down-regulated miRNAs during acute spinal cord injury. Mixed lineage kinase 3 (MLK3), a key factor of jun N-terminal kinase (JNK)/mitogen-activated protein kinase (MAPK) pathway, is the target of miR-138. The aim of this study was to investigate the role of miR-138 in H2O2-treated BV-2 cells.

METHODS

Murine microglia BV-2 cells were treated with H2O2 and tested for cell viability and miR-138 expression. The cells were then transfected with miR-138 agomir or miR-138 antagomir, and treated with 200 μM H2O2 for 24 h. The cellular apoptosis was detected by Aennexin V/PI staining. Expression of miR-138, MLK3, and other factors of JNK/MAPK pathway was detected.

RESULTS

After treatment of various concentrations of H2O2, the cell viabilities were reduced, and miR-138 expression was down-regulated. Compared to the control cells, over-expressing miR-138 in BV-2 cells reduced apoptosis rate from 24.2 % to 11.9 %. Western blot further showed that JNK, p-JNK, c-jun, p-c-jun, p38 MAPK, and p-p38 MAPK were down-regulated. Expression of pro-apoptosis factors iNOS and COX-2 were also down-regulated. Transfection of miR-138 antagomir produced the opposite effect of the transfection of miR-138 agomir.

CONCLUSION

miR-138 was able to reduce H2O2-induced apoptosis in BV-2 cells. The protective effect was related to the down-regulation of MLK3 proteins and sequentially inhibiting JNK/MAPK signaling pathway (Fig. 3, Ref. 27). Text in PDF www.elis.sk.

[Effects of continuous positive airway pressure on periodic limb movements during sleep in patients with obstructive sleep apnea]

Objective: To investigate the effects of continuous positive airway pressure (CPAP) on periodic limb movements during sleep (PLMS) in patients with obstructive sleep apnea (OSA). Methods: The polysomnography (PSG) data of 828 consecutive OSA outpatients from January 2015 to January 2017 who had undergone overnight CPAP titration were analyzed retrospectively. On the basis of changes in periodic limb movements index (PLMI) values (cut off level≥15/h) from baseline PSG (BPSG) to CPAP titration PSG, patients were assigned to one of the following four groups: persistent, CPAP-emergent, CPAP-disappeared, and non-PLMS. Results: Among 828 patients, 756 (91.3%) were male and 72 (8.7%) were female. The mean age was (45.7±10.7) years old, the mean body mass index (BMI) was (27.6±3.5) kg/m(2). The rate of patients was 3.9% in the persistent group, 10.3% in the CPAP-emergent group, 7.5% in the CPAP-disappearance group, and 78.4% in the non-PLMS group. Multivariate Logistic regression analysis revealed that female appeared to be associated with the persistent group (P=0.004); older age and higher apnea-hypopnea index (AHI) on BPSG appeared to be associated with the CPAP-emergent group (P=0.012, 0.030). On the other hand, older age was negatively associated with the non-PLMS group (P=0.006). Conclusion: Elderly patients with higher AHI at BPSG may present with CPAP-emergent PLMS.

[Gender differences of REM related obstructive sleep apnea-hypopnea syndrome]

Objective: To explore the gender differences of rapid-eye-movement (REM) related obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods: Consecutive patients with primary complaint of snoring from Sleep Medicine Center of West China Hospital between January 2016 and November 2016 were included in the study. All participants underwent one night polysomnography (PSG) and Epworth sleep scale (ESS) was estimated. The patients diagnosed with OSAHS were classified as REM related OSAHS (REM-OSAHS group) and non-rapid-eye-movement (NREM) related OSAHS (NREM-OSAHS group) based on the PSG parameters. And the gender differences of demographic and polysomnograpic characteristics in both groups were compared. The associations between apnea-hypopnea index (AHI) and body mass index (BMI), neck circumference and waist circumference among patients with OSAHS were explored by multiple linear regression analysis. Results: A total of 1 258 patients were diagnosed with OSAHS. There were 997 (79.3%) male and 261 (20.7%) female among these patients, the mean age was (46.4±12.0) years old and mean BMI was (26.6±3.4) kg/m(2). There were 236 patients (18.8%) classified into REM-OSAHS group, and 1 022 patients (81.2%) classified into NREM-OSAHS group; the proportion of REM-OSAHS in female was significantly higher than that in male (34.1% vs 14.7%, P<0.001). After controlling for age, drinking, smoking, hypnotics, coffee, strong tea and sleep related parameters, in NREM-OSAHS group, AHI was positively correlated with BMI, neck circumference and waist circumference (P<0.001) both in male and female. In REM-OSAHS group, AHI was positively correlated with BMI, neck circumference and waist circumference in female (P<0.05), but only significantly correlated with BMI and waist circumference in male (P<0.05). Conclusions: REM-OSAHS is commonly seen in female OSAHS patients. Evaluation of the influences of anthropometric data on the severity of REM-OSAHS should consider the impact of gender.

Meclizine Prevents Ovariectomy-Induced Bone Loss and Inhibits Osteoclastogenesis Partially by Upregulating PXR

Pregnane X receptor (PXR) which belongs to the nuclear hormone receptor superfamily plays vital roles in several biological functions, especially in the inflammatory procedure. Besides that, PXR is revealed by recent studies to have essential effects on bone tissue. As an agonist of PXR, meclizine is a piperazine-derived histamine H1 antagonist, and has been frequently used for prevention and treatment of vomiting and nausea. Because osteoclastogenesis is characterized by the activation of inflammation-related signaling pathways, we speculated that meclizine may affect formation and function of osteoclast. In the present study, we explored the effect of meclizine on RANKL-induced osteoclastogenesis both in vivo and in vitro. In primary bone marrow-derived macrophages (BMMs), meclizine reduced osteoclast formation and bone resorption in a dose-dependent manner, while knockdown of PXR with siRNA partially abrogated the osteoclastogenesis inhibition of meclizine. On the one hand, at the molecular level, meclizine attenuated RANKL-induced activation of c-Fos, NFATc1, nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPKs), including ERK and p38, but not JNK. Meanwhile, meclizine reduced the expression of osteoclast-specific genes, including TRAP, MMP9, Cathepsin K and NFATc1. On the other hand, meclizine decreased OVX-induced bone loss by repressing osteoclast activity. In conclusion, our results indicated that meclizine inhibits osteoclastogenesis via regulation of several RANKL signaling pathways and PXR was involved in the processes. Therefore, meclizine may be considered as a novel therapeutic candidate for osteoclast-related diseases.

Direct loop gain and bandwidth measurement of phase-locked loop

A simple and robust technique for directly measuring the loop gain and bandwidth of a phase-locked loop (PLL) is proposed. This technique can be used for the real-time measurement of the real loop gain in a closed PLL without breaking its locking state. The agreement of the measured loop gain and theoretical calculations proves the validity of the proposed measurement technique. This technique with a simple configuration can be easily expanded to other phase-locking systems whose loop gain and bandwidth should be measured precisely.

[The implantation of Bonebridge in bilateral congenital malformation of external and middle ear]

Objective: To evaluate the auditory efficacy of Bonebridge implantation in patients with bilateral congenital malformation of external and middle ear. Methods: Eleven cases (6 males and 5 females) had unilateral Bonebridge implantation. The age ranged from 8 to 26 and the average age was 16.9. Seven to ten days after operation, the first fitting was undergone. In acoustic sound field, the average auditory thresholds were respectively measured for unaided ears and Bonebridge implanted ears by pure tone auditory (PTA, 0.25, 0.5, 1, 2 and 4 kHz). For the group over 12-year-old, MSTM was applied to evaluate speech discrimination score (SDS). For the other cases, MLNT was used as the test material. The auditory efficacy post Bonebridge implantation would be analyzed and evaluated by comparing the differences between unaided ears and Bonebridge implanted ears. Results: The bone conduction audibility threshold after Bonebridge implantation was as well as the preoperative. The auditory threshold with Bonebridge aided was improved to 25-35 dB HL, when compared to that of the unaided ears in the sound field. The SDS in the group over 12-year-old was improved about 50%; the efficacy was slightly limited for the other two cases (both less than 12 years old). Statistical analysis showed that there were significant differences between unaided ears and Bonebridge implanted ears in the sound field and SDS(P<0.05). Conclusions: The auditory efficacy of Bonebridge is significant and noticeable in patients with bilateral congenital malformation of external and middle ear. Bonebridge provides a new and effective way for patient with congenital malformation of external and middle ear to reconstruct hearing.

[Vibrant soundbridge implantation of congenital atresia of oval window(with summary of nine cases]

Objective:To investigate the surgical effects of round window implantation of vibrant soundbridge(VSB)for patients with congenital oval window atresia.Method:Retrospectively analyze the clinical information of 9 cases of congenital oval window atresia as well as the pre-and post-operative hearing and speech results. Three of them had undergone or attempted the vestibulotomy but obtained poor results. All cases underwent round window implantation of VSB. Result:All patients obtained an improvement of 21-33 dBHL after implantation. In the speech recognition rate test, the average increase of disyllabic words was 62%, and 60% in the sentence test. During the follow-up of 51 months in average, 2 cases had a decline of auditory benefit and finally 1 case regained the improvement after reoperation. Conclusion:Round window implantation can get a fairly good result in congenital oval windows atresia cases.

[Association between subjective and objective sleepiness in obstructive sleep apnea hypopnea syndrome patients]

Objective: To examine the association between subjective sleepiness and objective sleepiness in Chinese obstructive sleep apnea hypopnea syndrome (OSAHS) patients. Methods: A total of 1 660 patients meeting the diagnostic criteria of OSAHS based on overnight polysomnography from West China Hospital, Sichuan University in the period from Jul 2010 to Jul 2014 were enrolled in the study. The Epworth Sleepiness Scale (ESS) and Multiple Sleep Latency Test (MSLT) were to evaluate subjective and objective sleepiness, respectively. The subjects were categorized into quartiles [A (0-4) (n=406), B (5-7) (n=325), C (8-12) (n=443), D(13-24) (n=486) groups] based on the ESS score distribution. Survival analysis was used to characterize the association between the ESS score and the mean sleep latency (MSL). Results: The apnea hypopnea index (AHI) in D group was higher than other three groups [(58.7±26.1) vs (36.8±24.2), (42.6±26.7), (45.7±26.6) events/h, all P<0.05]. The mean sleep latency in D group was shorter than other three groups [(8.0±4.6) vs (10.9±4.4), (10.3±4.8), (9.4±4.5) min, all P<0.05]. The Kaplan-Meier survivor functions across the ESS score quartiles were distinct and fourth quartiles were progressively associated with a greater tendency for falling asleep (χ(2)=77.76, P<0.001 by Log-rank test) in the daytime (The percentages of awaking patients in fourth quartiles were progressively lower at the same time). The adjusted hazard ratios for sleep onset during the MSLT for the group B, C and D were 1.05 (95%CI: 0.90-1.22), 1.22 (95%CI: 1.07-1.40), and 1.38 (95%CI: 1.20-1.60), respectively, comparing to group A. Conclusion: Subjective report of daytime sleepiness is consistent with the objective sleepiness in OSAHS patients.