Management after cataract surgery for patients with diabetic retinopathy: a systematic review and meta-analysis.

PURPOSE: To evaluate the safety and effectiveness of various treatment modalities in patients with diabetic retinopathy (DR) who underwent cataract surgery. METHODS: A comprehensive search for randomized controlled trials (RCTs) was conducted using the PubMed, Embase, Cochrane Library, and CNKI databases up to December 22, 2021. The safety and efficacy of treatment modalities were assessed using the risk ratio (RR) to compare the progression of DR and the mean difference to evaluate the best corrected visual acuity (BCVA) and macular thickness (MT). RESULTS: The meta-analysis of the RCTs revealed that anti-VEGF (anti-vascular endothelial growth factor) drugs significantly reduced the progression of DR [RR: 0.37 (95%CI 0.19, 0.70), P = 0.002] and improved BCVA [mean difference = - 0.06 (- 0.12, - 0.01), P = 0.03] in patients with pre-existing DR who underwent cataract surgery. Steroid drugs also showed a significant reduction in macular thickness [mean difference = - 55.63 (- 90.73, - 20.53), I2 = 56%, P = 0.002] in DR patients two weeks after cataract surgery compared to the control group. The safety profiles of different management options did not differ significantly. CONCLUSION: The present meta-analysis suggests that anti-VEGF drugs can effectively slow down the progression of diabetic retinopathy, improve BCVA, and reduce MT in DR patients who underwent cataract surgery. Steroid drugs also show promise in reducing MT. However, further studies with larger sample sizes are required to compare the efficacy and safety of different management options in a multi-center clinical setting.

Lanthanum-modified tobermorite synthesized from fly ash for efficient phosphate removal.

Phosphate removal from water by lanthanum-modified tobermorite synthesized from fly ash (LTFA) with different lanthanum concentrations was studied. LTFA samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and Brunauer‒Emmett‒Teller specific surface area analysis. The results showed that the LTFA samples were mainly composed of mesoporous tobermorite-11 Å, and LTFA1 with a lanthanum concentration of 0.15 M had a high specific surface area (83.82 m2/g) and pore volume (0.6778 cm3/g). The phosphate adsorption capacities of LTFA samples were highest at pH 3 and gradually decreased with increasing pH. The phosphate adsorption kinetics data on LTFA samples were most accurately described by the Elovich model. The adsorption isotherms were in the strongest agreement with the Temkin model, and LTFA1 showed the highest phosphate adsorption capacity (282.51 mg P/g), which was higher than that of most other lanthanum-modified adsorbents. LTFA1 presented highly selective adsorption of phosphate with other coexisting ions (HCO3-, Cl-, SO42-, and NO3-). In addition, phosphate was adsorbed onto LTFA samples by forming inner-sphere phosphate complexes and amorphous lanthanum phosphate. This study provides technical support for development of efficient fly ash-based phosphate adsorbents.

"Adjacent Bed Effect" of Total Knee Arthroplasty Patients During the Perioperative Period.

BACKGROUND: Knee osteoarthropathy is one of the most common degenerative joint diseases in the elderly, total knee arthroplasty (TKA) is the most commonly used treatment for end-stage knee osteoarthropathy. Negative emotions such as anxiety have been extensively documented in knee osteoarthropathy patients. AIM: This study aimed to investigate the Emotional Contagion during hospitalization in patients undergoing TKA. METHODS: Eligible subjects were divided into three case groups according to their anxiety states and bed arrangement. All subjects underwent a unilateral, cemented TKA under general anesthesia. Post-operative recovery outcomes including pain, pain behavior and physical function were recorded pre-operation, 1-day, 1 week, 2-weeks, 1-month and 3-months post-operation. RESULTS: A total of 38 subjects were included in the final analysis. Subjects with anxiety had higher Visual Analogue Scale pain scores, PROMIS-Pain Behavior scores than subjects without anxiety in the Contagion Group preoperation (p ≤ .05). Non-anxiety subjects hospitalized in beds physically adjacent to anxiety subjects experienced more severe pain and poorer function (p ≤ .05). After discharge, all clinical outcomes gradually became lower than anxiety subjects in the Contagion Group, reaching levels similar to non-anxiety subjects in the No Contagion Group within 1 month (p>.05). CONCLUSIONS: This study showed that patients with anxiety may have an "Adjacent Bed Effect" on patients with TKA in the adjacent bed, which may be associated with poorer postoperative recovery, including pain and physical function. We speculate this phenomenon can be effectively avoided by the nursing team through accurately assessing psychological status and reasonable bed arrangements in the inpatient assessment phase.

Association of variants in GJA8 with familial acorea-microphthalmia-cataract syndrome.

Congenital acorea is a rare disease with the absence of a pupil in the eye. To date, only one family and two isolated cases with congenital acorea have been reported. The gene associated with acorea has not been identified. In this study, we recruited a Chinese family acorea-microphthalmia-cataract syndrome. By analyzing the whole-exome sequencing (WES) data of this Chinese family, we revealed the association of a novel heterozygous variant, NM_005267.5:c.137G>A (p.G46E) in the gap junction protein alpha 8 (GJA8) gene encoding connexin 50 or CX50, with familial acorea-microphthalmia-cataract syndrome. Additionally, another variant, NM_005267.5:c.151G>A (p.D51N) in GJA8, was identified to co-segregate with this syndrome in an unrelated Japanese family. Ectopic expression of p.G46E and p.D51N mutant GJA8 genes in cultured cells caused protein mislocalization, suggesting that the p.G46E and p.D51N mutations in GJA8 impaired the function of the gap junction channels. These results established GJA8 as the first gene associated with familial acorea-microphthalmia-cataract syndrome.

Leukemia Inhibitory Factor Protects against Degeneration of Cone Photoreceptors Caused by RPE65 Deficiency.

BACKGROUND: Retinal pigment epithelium (RPE) 65 is a key enzyme in the visual cycle involved in the regeneration of 11-cis-retinal. Mutations in the human RPE65 gene cause Leber's congenital amaurosis (LCA), a severe form of an inherited retinal disorder. Animal models carrying Rpe65 mutations develop early-onset retinal degeneration. In particular, the cones degenerate faster than the rods. To date, gene therapy has been used successfully to treat RPE65-associated retinal disorders. However, gene therapy does not completely prevent progressive retinal degeneration in patients, possibly due to the vulnerability of cones in these patients. In the present study, we tested whether leukemia inhibitory factor (LIF), a trophic factor, protects cones in rd12 mice harboring a nonsense mutation in Rpe65. METHODS: LIF was administrated to rd12 mice by intravitreal microinjection. Apoptosis of retinal cells was analyzed by TUNEL assay. The degeneration of cone cells was evaluated by immunostaining of retinal sections and retinal flat-mounts. Signaling proteins regulated by LIF in the retinal and cultured cells were determined by immunoblotting. RESULTS: Intravitreal administration of LIF activated the STAT3 signaling pathway, thereby inhibiting photoreceptor apoptosis and preserving cones in rd12 mice. Niclosamide (NCL), an inhibitor of STAT3 signaling, effectively blocked STAT3 signaling and autophagy in cultured 661W cells treated with LIF. Co-administration of LIF with NCL to rd12 mice abolished the protective effect of LIF, suggesting that STAT3 signaling and autophagy mediate the protection. CONCLUSION: LIF is a potent factor that protects cones in rd12 mice. This finding implies that LIF can be used in combination with gene therapy to achieve better therapeutic outcomes for patients with RPE65-associated LCA.

[Application of femoral I.D.E.A.L localization in anterior cruciate ligament reconstruction with single bundle anterior cruciate ligament].

OBJECTIVE: To evaluate the effect of femoral I.D.E.A.L localization in single bundle anterior cruciate ligament reconstruction (ACLR). METHODS: From January 2019 to October 2022, 122 patients with anterior cruciate ligament injury were treated with ACLR, including 83 males and 39 females. The age ranged from 23 to 43 years old, with an average of (32.19 ±8.55) years old. The course of disease ranged from 1 week to 6 months. According to the different surgical schemes, the patients were divided into two groups, namely the traditional group, which adopted the over-the-top femoral lateral positioning scheme, including 64 patients. The I.D.E.A.L group adopted the I.D.E.A.L femoral lateral positioning scheme, including 58 patients. The patient has pain and dysfunction of knee joint before operation. MRI of knee joint indicates anterior cruciate ligament injury. The visual analogue scale(VAS), International Knee Documentation Committee(IKDC) scoring system and Lysholm scoring system were used to evaluate the knee joint function of the patient. KT-2000 was used to detect the recovery of knee joint after operation and to count the postoperative complications. RESULTS: The wounds healed well after operation. One hundred and twenty-tow patients were followed up for 15 to 46 months, with an average of (25.45±9.22) months. The knee joint stability of patients after operation was significantly increased. The VAS at 1 day and 1 week after operation of patients in the I.D.E.A.L group was significantly lower than that in the traditional group(P<0.05). The IKDC score and Lysholm score of patients in the I.D.E.A.L group were significantly higher than those in the traditional group(P<0.05). In the traditional group, there were 6 cases of short-term (<1 month) complications and 19 cases of long-term (≥1 month)complicatios. In the I.D.E.A.L group, there were 3 cases of short-term complications and 7cases of long-term complications(P<0.05). CONCLUSION: The single bundle anterior cruciate ligament reconstruction and femoral I.D.E.A.L positioning can achieve better early postoperative effect and reduce early postoperative pain.

Rhodopsin-associated retinal dystrophy: Disease mechanisms and therapeutic strategies.

Rhodopsin is a light-sensitive G protein-coupled receptor that initiates the phototransduction cascade in rod photoreceptors. Mutations in the rhodopsin-encoding gene RHO are the leading cause of autosomal dominant retinitis pigmentosa (ADRP). To date, more than 200 mutations have been identified in RHO. The high allelic heterogeneity of RHO mutations suggests complicated pathogenic mechanisms. Here, we discuss representative RHO mutations as examples to briefly summarize the mechanisms underlying rhodopsin-related retinal dystrophy, which include but are not limited to endoplasmic reticulum stress and calcium ion dysregulation resulting from protein misfolding, mistrafficking, and malfunction. Based on recent advances in our understanding of disease mechanisms, various treatment methods, including adaptation, whole-eye electrical stimulation, and small molecular compounds, have been developed. Additionally, innovative therapeutic treatment strategies, such as antisense oligonucleotide therapy, gene therapy, optogenetic therapy, and stem cell therapy, have achieved promising outcomes in preclinical disease models of rhodopsin mutations. Successful translation of these treatment strategies may effectively ameliorate, prevent or rescue vision loss related to rhodopsin mutations.

[Repair of osteoarthritis in animal model with exosomes derived from BMSCs transfected by the siRNA -Piezo1 through CT navigation].

OBJECTIVE: To investigate the effect of the exosomes from bone marrow mesenchymal stem cells (BMSCs) transfected with silence plasmid of Piezol small interference RNA (siRNA)on osteoarthritis (OA) animal model. METHODS: Twenty male SD rats with specific pathogen free (SPF) were selected, ranging in age from 5.46 to 6.96 months, with a mean of (6.21± 0.75) months;and ranging in weight from 385.76 g to 428.66 g, with a mean of (407.21±21.45) g. BMSCs were extracted. The siRNA silencing plasmid of piezo1 was constructed by siRNA technology. After lentivirus was transfected into BMSCs, the exosomes were extracted. At the cellular level, BMSCs were divided into blank plasmid group and siRNA silencing plasmid group according to whether siRNA-Piezo1 was transfected or not. The osteogenic induction ability of siRNA-Piezo1 on BMSCs was detected by RT-PCR and Western blot. At the animal model level, the OA model was established by surgical resection of cruciate ligament of knee joint.According to different treatment schemes, SD rats were divided into 4 groups:blank control group, model group, BMSCs group and exosome group. SD rats in the blank control group were not treated. In the model group, the cruciate ligaments of rats were excised and OA animal model was established. In BMSCs group, BMSCs were injected into knee joint under CT guidance after OA model establishment, and the cell volume was 5×105/ml, loading amount of 2 ml, twice a week for 4 weeks. In the exosome group, 100 µg exosomes from siRNA BMSCs were added twice a week for 4 weeks after OA model establishment. The cartilage of the animal model was detected by hematoxylin eosin (HE) staining and safranin solid green staining, and quantified by the modified Minkin score and the score of the international society for osteoarthritis research (OARSI). Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the relative mRNA expression level of aggrecan type II collagen in cartilage. RESULTS: The lentivirus transfection efficiency was(92.11±4.22)%. RT-PCR showed that the relative expression of Piezo1 mRNA in blank plasmid group was 1.07±0.06, which was significantly different from that of 0.31±0.01 in siRNA silencing plasmid group (t=2.907, P<0.05). The results of HE staining and safranine solid green staining showed that there was cartilage structure and smooth cartilage surface in the knee joint of SD rats in the blank control group. The knee joint structure in the model group had been completely destroyed, the knee joint cartilage structure in the BMSCs group was not clear, and there were subchondral bone components in the OA rats in the exosomes group. There was significant difference between the modified Minkin score of HE staining and the OARSI score of safranin solid green staining (F=15.903, 19.005;P<0.05). Among them, the repair effect of exosome group was significantly better than that of BMSCs group and model group (P<0.05). RT-PCR results showed that the relative expression of aggrecan mRNA in BMSCs group was significantly higher than that in model group (P< 0.05), and the relative expression of aggrecan mRNA in exosome group was higher than that in BMSCs group and model group (P<0.05). The relative expression of CollagenⅡmRNA in BMSCs group was higher than that in model group (P<0.05), and the relative expression of CollagenⅡmRNA in exosomes group was higher than that in BMSCs group and model group (P<0.05). CONCLUSION: Piezo1 siRNA silencing vector can promote the differentiation of BMSCs into chondrocytes and effectively inhibit the progression of OA, so as to delay the disease of OA.

Hsa_circ_0010957 level is increased and sponges microRNA­125b in CD4+ T cells of patients with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a severe autoimmune disorder, the pathogenesis of which remains largely unknown. The present study aimed to investigate the role and mechanism of circular RNAs in the etiopathogenesis of SLE. CD4+ T cells in patients with SLE expressed higher levels of hsa_circ_0010957 compared with healthy individuals and was a good differentiator of the active from inactive SLE disease. It was also determined that hsa_circ_0010957 mediated microRNA (miR)­125b/STAT3 signaling and subsequent secretion of inflammatory cytokines interleukin (IL)­18, IL­6 and IL­17, which are important factors in the process of SLE. Hsa_circ_0010957 abrogated the proinflammatory effect of IL­6 via the blockade of STAT3 signaling. In conclusion, increased hsa_circ_0010957 may be involved in SLE pathogenesis via miR­125b/STAT3 signaling. Hsa_circ_0010957 promises to be a potential biomarker and therapeutic target for SLE.

MiRNA-1271-5p regulates osteogenic differentiation of human bone marrow-derived mesenchymal stem cells by targeting forkhead box O1 (FOXO1).

Forkhead box O1 (FOXO1) is a key regulator of osteogenesis. The aim of this study was to identify the mechanisms of microRNAs (miRNAs) targeting FOXO1 in osteogenic differentiation of human bone marrow mesenchymal stem cells (hMSCs). Three miRNA target prediction programs were used to search for potential miRNAs that target FOXO1. Quantitative real-time polymerase chain reaction was conducted to detect the expression of miR-1271-5p and FOXO1 during osteogenic differentiation. Target gene prediction and screening, luciferase reporter assay was used to verify the downstream target gene of miR-1271-5p. The expression levels of FOXO1 and Runx2 were detected by RT-qPCR and Western blot analysis. Alkaline phosphatase (ALP) activity and matrix mineralization were detected by biochemical methods. The expression levels of Runx2, ALP, and osteocalcin were detected by RT-qPCR. Our results showed that miR-1271-5p was downregulated during osteogenic induction. And the expression levels of miR-1271-5p were higher in osteoporotic tissues than that in adjacent nonosteoporotic tissues. The expression levels of FOXO1 were lower in osteoporotic tissues than that in adjacent nonosteoporotic tissues. And a negative correlation was found between miR-1271-5p and FOXO1 in osteoporotic tissues. Overexpression of miR-1271-5p downregulated FOXO1 and inhibited osteogenic differentiation in hMSCs. Overexpression of miR-1271-5p downregulated the expression of osteogenic markers and reduced ALP activity. In addition, ectopic expression of FOXO1 reversed the effect of miR-1271-5p on osteogenic differentiation. In conclusion, miR-1271-5p functioned as a therapeutic target of osteogenic differentiation in hMSCs by inhibiting FOXO1, which provides valuable insights into the use of miR-1271-5p as a target in the treatment of osteoporosis and other bone metabolic diseases.

Comparison of postoperative effectiveness of less invasive short external rotator sparing approach versus standard posterior approach for total hip arthroplasty.

BACKGROUND: Most of the studies assessing the corrective posterior total hip arthroplasty (THA) mainly focused on the mini-incision approach. Studies exploring the short external rotator sparing approach are rare. Therefore, this study aimed to compare the effectiveness of standard posterior approach and short external rotator sparing approach. METHODS: This prospective observational study included 126 patients who underwent THA in June 2017-June 2018. Patients were assigned to standard (standard posterior approach) and corrective (short external rotator sparing approach) groups based on the surgical method. Surgical data were recorded postoperatively. Postoperative hip joint recovery was assessed using the times to ambulation and independent stair use, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, Harris score, and Oxford hip score (OHS) at 2 and 8 postoperative weeks. The visual analog scale (VAS) was used for postoperative pain assessment. RESULTS: Postoperative changes of creatine kinase (CK), myoglobin, CRP, and prosthesis position were similar in both groups (P > 0.05). However, intraoperative blood loss (P < 0.001) and postoperative 6-h drainage volume (P = 0.03), hospital stay, blood transfusion rate, and times to ambulation and independent stair use were significantly reduced in the corrective group. Postoperatively, Oxford, and WOMAC scores significantly decreased in both groups. After surgery, the VAS score was more overtly decreased in the corrective group compared with the standard group. CONCLUSIONS: This study concluded that the less invasive short external rotator sparing approach for THA caused less damage, reducing perioperative blood loss, shortening functional recovery time, maintaining prosthesis stability, and improving postoperative pain.

CRISPR/Cas9 facilitates genomic editing for large-scale functional studies in pluripotent stem cell cultures.

Pluripotent stem cell (PSC) cultures form an integral part of biomedical and medical research due to their capacity to rapidly proliferate and differentiate into hundreds of highly specialized cell types. This makes them a highly useful tool in exploring human physiology and disease. Genomic editing of PSC cultures is an essential method of attaining answers to basic physiological functions, developing in vitro models of human disease, and exploring potential therapeutic strategies and the identification of drug targets. Achieving reliable and efficient genomic editing is an important aspect of using large-scale PSC cultures. The CRISPR/Cas9 genomic editing tool has facilitated highly efficient gene knockout, gene correction, or gene modifications through the design and use of single-guide RNAs which are delivered to the target DNA via Cas9. CRISPR/Cas9 modification of PSCs has furthered the understanding of basic physiology and has been utilized to develop in vitro disease models, to test therapeutic strategies, and to facilitate regenerative or tissue repair approaches. In this review, we discuss the benefits of the CRISPR/Cas9 system in large-scale PSC cultures.

Downregulation of microRNA-23b-3p alleviates IL-1ß-induced injury in chondrogenic CHON-001 cells.

BACKGROUND: Osteoarthritis (OA) is a common joint disease, which is characterized by degradation of articular cartilage. Evidence indicated that miR-23b-3p was upregulated in cartilage tissues of a patient with OA. However, the mechanism by which miR-23b-3p regulates the occurrence and development of OA remains unclear. Thus, this study aimed to investigate the role of miR-23b-3p in the progression of OA. METHODS: In this study, qRT-PCR was used to measure the expression of miR-23b-3p in OA tissue samples and normal controls, respectively. Western blotting assay was performed to detect the levels of collagen II, aggrecan, Bax and active caspase 3 in CHON-001 cells. In addition, the dual-luciferase reporter system assay was used to detect the interaction between miR-23b-3p and COL11A2 in OA. RESULTS: The levels of miR-23b-3p were upregulated, while the expressions of collagen II and aggrecan were decreased in OA tissues and in IL-1ß-treated CHON-001 cells. In addition, IL-1ß significantly induced apoptosis of CHON-001 cells via increasing the levels of Bax and active caspase 3. However, downregulation of miR-23b-3p markedly inhibited IL-1ß-induced apoptosis in CHON-001 cells via increasing the collagen II and aggrecan levels and decreasing Bax and active caspase 3 expressions. Meanwhile, dual-luciferase assay showed that COL11A2 was the direct target of miR-23b-3p in CHON-001 cells. Overexpression of miR-23b-3p markedly decreased the level of COL11A2 in cells. Moreover, downregulation of miR-23b-3p alleviated synovitis/cartilage destruction and reduced Osteoarthritis Research Society International scores and subchondral bone thickness in vivo. CONCLUSION: Downregulation of miR-23b-3p could alleviate the progression of OA through upregulating COL11A2 in vivo and in vitro. Therefore, downregulation of miR-23b-3p might be a potential therapeutic strategy for the treatment of OA.

Up-regulated HIF-2α contributes to the Osteoarthritis development through mediating the primary cilia loss.

BACKGROUNDS: Up-regulated HIF-2α (hypoxia induced factor 2) had been demonstrated to contribute to Osteoarthritis (OA) development via inducing the expression of matrix-degrading enzymes. However, the HIF-2α also could promote primary cilia loss through HIF-2α/AURKA (Aurora kinase A)/NEDD9 pathway. And the primary cilia dysfunction is another characteristic of the OA. Thus, we investigated here whether the HIF-2α also contributes the OA development through mediating the primary cilia loss. METHODS: The primary chondrocytes were isolated from the experimental OA mice induced by destabilization of the medial meniscus (DMM). Chondrocytes were cultured under normoxia (21% O2) or hypoxia (2% O2) conditions. The HIF-1α and HIF-2α expressions were assessed by western blot. The cilia formation was counted by immuno-staining the acetylated tubulin. The contribution of HIF-1α or HIF-2α to the primary cilia loss was assessed by knocking-down the HIF-1α or HIF-2α individually. The HIF-2α/AURKA/NEDD9 pathway was validated through over-expressing or knocking-down specific components of the pathway and then counting the primary cilia number. Finally, the pathway was further confirmed in the OA mice. RESULTS: Hypoxia could induce the expression of both HIF-1α and HIF-2α, and also reduce the number of primary cilia on the chondrocytes isolated from the experimental OA mice. Knocking-down or over-expressing HIF-1α or HIF-2α individually showed that the HIF-2α could induce the primary cilia reduction rather than the HIF-1α. Manipulating the HIF-2α expression could positively affect the AURKA and NEDD9 expression. Manipulating the AURKA and NEDD9 expressions could reverse the function of HIF-2α on primary cilia. In the mice, knocking-down both AURKA and NEDD9 could alleviate the OA development significantly. CONCLUSION: Up-regulated HIF-2α contributes to the Osteoarthritis development through mediating the primary cilia loss, which might be developed as therapeutic targets for OA treatment.

A LINC00341-mediated regulatory pathway supports chondrocyte survival and may prevent osteoarthritis progression.

Osteoarthritis (OA) is the most common degenerative joint disease and results from progressive loss and destruction of articular cartilage and the underlying bone. The disease affects millions of people worldwide with an associated risk of mobility disability. However, the molecular basis underlying OA initiation and progression is not well understood and, currently, there is no effective intervention available to decelerate disease progression or restore degraded cartilage. We have found that lncRNA long intergenic nonprotein coding RNA 341 (LINC00341) is aberrantly downregulated in OA patient tissues and cultured OA chondrocytes. This is likely responsible for the increased apoptosis of chondrocytes and pathological destruction of cartilage. Further investigation has revealed that LINC00341 interacts with miR-141 to suppress its functional binding to the 3'-untranslated region of YY1-associated factor 2 (YAF2) messenger RNA. Aberrant downregulation of LINC00341 thus may ultimately lead to inhibition of the YAF2 protein, which has been implicated to be an antiapoptotic factor. Our study has revealed a new noncoding RNA-mediated regulatory network that highly likely protects chondrocytes by preventing apoptosis under normal conditions. The results will help further explore the molecular details pertaining to the progression of OA and stimulate efforts to develop effective therapies.

Study on the mechanism of excessive apoptosis of nucleus pulposus cells induced by shRNA-Piezo1 under abnormal mechanical stretch stress.

OBJECTIVE: The aim of the study was to explore the mechanism of excessive apoptosis of nucleus pulposus cells induced by short hairpin RNA (shRNA) Piezo type mechanosensitive ion channel component 1 (Piezo1) under abnormal mechanical stretch stress. METHODS: In vitro mechanical stretch stress model of nucleus pulposus cells in vitro was established, in which the expression of Piezo1 was interfered by transfection of shRNA-Piezo1 interfering vector. Both messenger RNA and protein level of Piezo1 were measured by reverse-transcription polymerase chain reaction and Western blot analysis, respectively. Cytoplasmic Ca2+ was detected by Fluo3-AM kit, and changes of mitochondrial membrane potential in cells were detected using Cell Meter Assay kit. Finally, the apoptosis was evaluated with annexin V-fluorescein isothiocyanate kit. RESULTS: The highest transfection efficiency of lentivirus titer was 1 × 10 TU/mL and the nucleus pulposus cells were transfected with plural multiplicity of infection = 50. Homo-3201 sequence exhibited the most effective silencing effect and was used in subsequent experiments as the default sequence of shRNA-Piezo1. The calcium content in the cytoplasm of the tension stress group increased significantly compared with that in the blank control group ( q = 3.773; P < 0.05). The level of cytosolic calcium in shRNA-interference group was significantly lower than that in stretch stress group ( q = 5.159; P < 0.05). Stretch stress treatment resulted in an elevated ratio of mitochondrial membrane potential turnover as opposed to blank control group ( q = 4.332; P < 0.05), while shRNA-interference group showed smaller ratio of mitochondrial membrane potential turnover than that in stretch stress group ( q = 4.974; P < 0.05). Similar results were also observed in apoptosis rate analysis ( q = 3.175; P < 0.05). CONCLUSION: ShRNA-Piezo1 can protect cells by reducing the level of intracellular Ca2+ and the change of mitochondrial membrane potential.

Arthroscopic debridement of anterior ankle impingement in patients with chronic lateral ankle instability.

BACKGROUND: The aim of this study was to determine the functional and radiological outcomes of arthroscopic treatment of anterior ankle impingement (AAI) in patients with chronic lateral ankle instability (CAI). METHODS: All patients with CAI between June 2012 and May 2015 were invited to participate in this investigation. All of them accepted open modified Broström repair of lateral ankle ligaments and were divided into two groups: AAI group (with anterior ankle impingement) and pure CAI group (without anterior ankle impingement). All of them were followed up using American Orthopaedic Foot and Ankle Society Score (AOFAS), Karlsson Ankle Functional Score and Tegner activity score. Ankle dorsiflexion was also examined. X-ray examination was applied to investigate anterior tibiotalar osteophytes. RESULTS: Finally, a total of 60 patients were followed up at a mean of 37 ± 10 months, including 22 patients in the AAI group and 38 patients in the pure CAI group. Preoperatively, the AAI group had significant lower AOFAS score (62.9 ± 11.7 vs 72.9 ± 11.1; p = 0.002) and Tegner activity score (1.5 ± 0.8 vs 2.1 ± 1.0; p = 0.04) respectively when compared with the pure CAI group. The ankle dorsiflexion of the AAI group (13 ± 2.1) was also significantly lower than that of the pure CAI group (26.2 ± 2.1) (p = 0.001). However, there was no significant difference in the AOFAS score or the Karlsson score or the Tegner score or the Ankle dorsiflexion between the two groups postoperatively. The postoperative X-ray images demonstrated complete osteophyte resection in all patients, and no recurrence of osteophyte. CONCLUSION: The functional outcome scores and dorsiflexion had significantly improved postoperatively. Combined treatment of chronic ankle instability and anterior ankle impingement produced satisfactory surgical outcomes in patients with CAI accompanied by anterior ankle impingement symptom.

[Expression characteristics of Piezo1 protein in stress models of human degenerative chondrocytes].

OBJECTIVE: To explore the expression characteristics of new mechanosensitive ion channel Piezo1 protein in stress models of human degenerative chondrocytes. METHODS: The stress stimulation model of human degenerative chondrocytes in vitro was constructed. Multi-channel cell stretch stress loading system FX-4000T was used to treat chondrocytes. According to the results of pre-test, the loading frequency of 0.5 Hz and the cell elongation of 20% were loaded. According to cell processing time, it was divided into 0 h, 2 h, 12 h, 24 h and 48 h mechanical stress group. The RT-PCR and Western-blot were used to test the expression of the Piezo1, also the Laser scanning confocal microscope (LSCM) was used to test the intensity of the fluorescence of the Piezo1. RESULTS: (1)The result of the RT-PCR showed that the expression of the Piezo1 in the 2 h group was higher than the 0 h group(F=13.917, q=0.037 1, P<0.05). The expression of the piezo1 in the 24 h group was the highest. While the expression of the piezo1 in the 48 h group was lower than the expression of the piezo1 in the 24 h group(F=13.917, q=0.049 5, P<0.05). (2)The result of the Western-blot showed that the 2 h group was higher than the 0 h group(F=19.341, q=0.037 1, P<0.05). The expression of the 24 h had the highest expression which was higher than the 48 h group(F=19.341, q=0.017 7, P<0.05). (3)The Piezo1 protein was extensively expressed in the cytoplasm and nucleus of the nucleus pulposus cells. And with the increase of stress processing time, the fluorescence intensity of the protein also increased. CONCLUSIONS: In human degeneration cartilage cells, the new mechanio sensitive ion channel Piezo1 protein has a trace expression. After loading periodic mechanical tensile force, the expression of Piezo1 protein increases with time dependence.

Interferonregulatoryfactor-8(IRF-8) regulates the expression of matrix metalloproteinase-13 (MMP-13) in chondrocytes.

Low levels of inflammation-induced expression of matrix metalloproteinase (MMP) play a crucial role in articular cartilage matrix destruction in osteoarthritis (OA) patients. Interferon regulatory factor-8 (IRF-8), an important member in the IRF family, plays a key role in regulating the inflammation-related signaling pathway. The aim of this study is to investigate the physiological roles of IRF-8 in the pathological progression of OA. We found that IRF-8 was expressed in human primary chondrocytes. Interestingly, the expression of IRF-8 was upregulated in OA chondrocytes. In addition, IRF-8 was increased in response to interleukin-1ß (IL-1ß) treatment, mediated by the Janus kinase 2 (JAK2) pathway. Overexpression of IRF-8 in human chondrocytes by transduction with lentiviral-IRF-8 exacerbated IL-1ß-induced expression of matrix metalloproteinase-13 (MMP-13) in human chondrocytes. In contrast, knockdown of IRF-8 inhibited IL-1ß-induced expression of MMP-13. Importantly, IRF-8 could bind to the promoter of MMP-13 and stimulate its activity. Additionally, overexpression of IRF-8 exacerbated IL-1ß-induced degradation of type II collagen. However, silencing IRF-8 abrogated the degradation of type II collagen. Taken together, our findings identified a novel function of IRF-8 in regulating articular cartilage matrix destruction by promoting the expression of MMP-13.

Effects of heat-killed Lactobacillus pentosus S-PT84 on postprandial hypertriacylglycerolemia in rats.

The effect of Lactobacillus pentosus strain S-PT84 (S-PT84) on postprandial hypertriacylglycerolemia was investigated in rats. S-PT84 dose-dependently inhibited the hydrolysis of triacylglycerols by pancreatic lipase in vitro. Intragastric administration of S-PT84 significantly reduced the lymphatic recovery of (3)H-trioleoylglycerol up to 8 h. The oral administration of a fat emulsion, with or without S-PT84, resulted in the concentration of plasma triacylglycerol 2 h and 3 h after administration being significantly lower in the S-PT84 group than in the group without S-PT84 (control group). These results suggest that S-PT84 alleviated postprandial hypertriacylglycerolemia by delaying triacylglycerol absorption in the intestine through the inhibition of pancreatic lipase.