High-quality AFM image acquisition of living cells by modified residual encoder-decoder network.

Atomic force microscope enables ultra-precision imaging of living cells. However, atomic force microscope imaging is a complex and time-consuming process. The obtained images of living cells usually have low resolution and are easily influenced by noise leading to unsatisfactory imaging quality, obstructing the research and analysis based on cell images. Herein, an adaptive attention image reconstruction network based on residual encoder-decoder was proposed, through the combination of deep learning technology and atomic force microscope imaging supporting high-quality cell image acquisition. Compared with other learning-based methods, the proposed network showed higher peak signal-to-noise ratio, higher structural similarity and better image reconstruction performances. In addition, the cell images reconstructed by each method were used for cell recognition, and the cell images reconstructed by the proposed network had the highest cell recognition rate. The proposed network has brought insights into the atomic force microscope-based imaging of living cells and cell image reconstruction, which is of great significance in biological and medical research.

Determining the degree of chromosomal instability in breast cancer cells by atomic force microscopy.

Chromosomal instability (CIN) is a source of genetic variation and is highly linked to the malignance of cancer. Determining the degree of CIN is necessary for understanding the role that it plays in tumor development. There is currently a lack of research on high-resolution characterization of CIN and the relationship between CIN and cell mechanics. Here, a method to determine CIN of breast cancer cells by high resolution imaging with atomic force microscopy (AFM) is explored. The numerical and structural changes of chromosomes in human breast cells (MCF-10A), moderately malignant breast cells (MCF-7) and highly malignant breast cells (MDA-MB-231) were observed and analyzed by AFM. Meanwhile, the nuclei, cytoskeleton and cell mechanics of the three kinds of cells were also investigated. The results showed the differences in CIN between the benign and cancer cells. Also, the degree of structural CIN increased with enhanced malignancy of cancer cells. This was also demonstrated by calculating the probability of micronucleus formation in these three kinds of cells. Meanwhile, we found that the area of the nucleus was related to the number of chromosomes in the nucleus. In addition, reduced or even aggregated actin fibers led to decreased elasticities in MCF-7 and MDA-MB-231 cells. It was found that the rearrangement of actin fibers would affect the nucleus, and then lead to wrong mitosis and CIN. Using AFM to detect chromosomal changes in cells with different malignancy degrees provides a new detection method for the study of cell carcinogenesis with a perspective for targeted therapy of cancer.

Clinical applications and cadaveric study of the free descending genicular artery perforator flap without the saphenous vein.

BACKGROUND: The descending genicular artery (DGA) and medial thigh region have been underused as donor sites for perforator flaps. This study evaluated the anatomical relationship between the perforators of the DGA and the saphenous vein (SV) to review the clinical applications of the free descending genicular artery perforator (DGAP) flap for locoregional reconstruction. METHODS: Fifteen cadavers were arterially perfused with red latex and dissected. Thirty-one patients with extremity tissue defects were treated with a free DGAP flap, including six patients who received a chimeric flap. The minimum distance between the DGAP and the SV was measured during surgery. RESULTS: In all patients, the skin branch of the descending genicular artery was found in the medial femoral condyle plane in front of the SV. The average distance between the descending genicular artery perforator and the SV was 3.71 ± 0.38 cm (range: 2.9-4.3 cm). Thirty flaps survived completely, and one flap developed partial necrosis; however, this flap healed two weeks after skin grafting. The average follow-up time was 11.23 months. CONCLUSIONS: We conclude that the SV can be preserved when harvesting the descending genicular artery perforator flap, causing less damage to the donor site and having no effect on flap survival. The free descending genicular artery perforator flap without the SV is a better therapy for complicated tissue defects.

Integrated Untargeted Metabolome, Full-Length Sequencing and Transcriptome Analyses Reveal the Mechanism of Flavonoid Biosynthesis in Blueberry (Vaccinium spp.) Fruit.

As a highly economic berry fruit crop, blueberry is enjoyed by most people and has various potential health benefits, many of which are attributed to the relatively high concentrations of flavonoids. To obtain more accurate and comprehensive transcripts, the full-length transcriptome of half-highbush blueberry (Vaccinium corymbosum/angustifolium cultivar Northland) obtained using single molecule real-time and next-generation sequencing technologies was reported for the first time. Overall, 147,569 consensus transcripts (average length, 2738 bp; N50, 3176 bp) were obtained. After quality control steps, 63,425 high-quality isoforms were obtained and 5030 novel genes, 3002 long non-coding RNAs, 3946 transcription factor genes (TFs), 30,540 alternative splicing events, and 2285 fusion gene pairs were identified. To better explore the molecular mechanism of flavonoid biosynthesis in mature blueberry fruit, an integrative analysis of the metabolome and transcriptome was performed on the exocarp, sarcocarp, and seed. A relatively complete biosynthesis pathway map of phenylpropanoids, flavonoids, and proanthocyanins in blueberry was constructed. The results of the joint analysis showed that the 228 functional genes and 42 TFs regulated 78 differentially expressed metabolites within the biosynthesis pathway of phenylpropanoids/flavonoids. O2PLS analysis results showed that the key metabolites differentially accumulated in blueberry fruit tissues were albireodelphin, delphinidin 3,5-diglucoside, delphinidin 3-O-rutinoside, and delphinidin 3-O-sophoroside, and 10 structural genes (4 Vc4CLs, 3 VcBZ1s, 1 VcUGT75C1, 1 VcAT, and 1 VcUGAT), 4 transporter genes (1 VcGSTF and 3 VcMATEs), and 10 TFs (1 VcMYB, 2 VcbHLHs, 4 VcWD40s, and 3 VcNACs) exhibited strong correlations with 4 delphinidin glycosides. These findings provide insights into the molecular mechanisms of flavonoid biosynthesis and accumulation in blueberry fruit.

Cell recognition based on atomic force microscopy and modified residual neural network.

Cell recognition methods are in high demand in cell biology and medicine, and the method based on atomic force microscopy (AFM) shows a great value in application. The difference in mechanical properties or morphology of cells has been frequently used to detect whether cells are cancerous, but this detection method cannot be a general means for cancer cell detection, and the traditional artificial feature extraction method also has its limitations. In this work, we proposed an analytic method based on the physical properties of cells and deep learning method for recognizing cell types. The residual neural network used for recognition was modified by multi-scale convolutional fusion, attention mechanism and depthwise separable convolution, so as to optimize feature extraction and reduce operation costs. In the method, the collected cells were imaged by AFM, and the processed images were analyzed by the optimized convolutional neural network. The recognition results of two groups of cells (HL-7702 and SMMC-7721, SGC-7901 and GES-1) by this method show that the recognition rate of dataset with the combination of cell surface morphology, adhesion and Young's modulus is higher, and the recognition rate of the dataset with optimal resolution is higher. Our study indicated that the recognition of physical properties of cells using deep learning technology can serve as a universal and effective method for the automated analysis of cell information.

Cancer Development in Hepatocytes by Long-Term Induction of Hypoxic Hepatocellular Carcinoma Cell (HCC)-Derived Exosomes In Vivo and In Vitro.

Hypoxic tumor cell-derived exosomes play a key role in the occurrence, development, and metastasis of tumors. However, the mechanism of hypoxia-mediated metastasis remains unclear. In this study, hypoxic hepatocellular carcinoma cell (HCC-LM3)-derived exosomes (H-LM3-exos) were used to induce hepatocytes (HL-7702) over a long term (40 passages in 120 days). A nude mouse experiment further verified the effect of H-LM3-exos on tumor growth and metastasis. The process of cancer development in hepatocytes induced by H-LM3-exos was analyzed using both biological and physical techniques, and the results showed that the proliferation and soft agar growth abilities of the transformed cells were enhanced. The concentration of tumor markers secreted by transformed cells was increased, the cytoskeleton was disordered, and the migration ability was enhanced and was accompanied by epithelial-mesenchymal transition (EMT). Transcriptome results showed that differentially expressed genes between transformed cells and hepatocytes were enriched in cancer-related signaling pathways. The degree of cancer development in transformed cells was enhanced by an increase in H-LM3-exos-induced passages. Nude mice treated with different concentrations of H-LM3-exos showed different degrees of tumor growth and liver lesions. The physical properties of the cells were characterized by atomic force microscopy. Compared with the hepatocytes, the height and roughness of the transformed cells were increased, while the adhesion and elastic modulus were decreased. The changes in physical properties of primary tumor cells and hepatocytes in nude mice were consistent with this trend. Our study linking omics with the physical properties of cells provides a new direction for studying the mechanisms of cancer development and metastasis.

Hydroxy-Rich Covalent Organic Framework for the Efficient Catalysis of the Cycloaddition of CO2.

The cycloaddition of CO2 with epoxides to cyclic carbonates is one of the most promising and green pathways for CO2 utilization, and the development of highly efficient catalysts remains a challenge. In this work, a novel hydroxy-rich covalent organic framework (TFPB-DHBD-COF) was synthesized, and it served as an efficient heterogeneous catalyst for the reaction of CO2 with 1,2-epoxybutane under mild conditions, providing the desired products in 90% conversion. The abundant hydroxy groups in the pore channels of TFPB-DHBD-COF could not only activate epoxides and CO2 via hydrogen bonding but also obviously enhance its stability through intramolecular five-membered ring hydrogen bonding. Thus, this COF also exhibited outstanding stability and tolerance for diverse substrates. Undoubtedly, this work has enriched the application of tailored COFs in the activation and utilization of CO2.

Use of Atomic Force Microscopy in UVB-Induced Chromosome Damage Provides Important Bioinformation for Cell Damage Assessment.

The chromosomal structure derived from UVB-stimulated HaCaT cells was detected by atomic force microscopy (AFM) to evaluate the effect of UVB irradiation. The results showed that the higher the UVB irradiation dose, the more the cells that had chromosome aberration. At the same time, different representative types of chromosome structural aberrations were investigated. We also revealed damage to both DNA and cells under the corresponding irradiation doses. It was found that the degree of DNA damage was directly proportional to the irradiation dose. The mechanical properties of cells were also changed after UVB irradiation, suggesting that cells experienced a series of chain reactions from inside to outside after irradiation. The high-resolution imaging of chromosome structures by AFM after UVB irradiation enables us to relate the damage between chromosomes, DNA, and cells caused by UVB irradiation and provides specific information on genetic effects.

Lipid Droplet-Specific Dual-Response Fluorescent Probe for the Detection of Polarity and H2O2 and Its Application in Living Cells.

H2O2 and polarity are quite important in many physiological and pathological processes, and their relationship is complicated and obscure for researchers. Thus, it is vital and challenging to achieve simultaneous detection of H2O2 and polarity in vivo. Herein, the first naphthalimide-triphenylamine-based dual-site fluorescent probe NATPA is developed for simultaneously imaging intracellular H2O2 and polarity fluctuations. It exhibits excellent sensitivity (LOD = 44 nM), selectivity, and fast response (15 min) to H2O2 and a superior capacity for detecting polarity upon the intramolecular charge transfer (ICT) effect. Besides, the probe displays low cytotoxicity and lipid droplet targeting and is further applied in imaging H2O2 and polarity fluctuations in HepG2 and L-02 cells, so that NATPA is qualified to distinguish cancer cells from normal cells. This research contributes a new design principle for the construction of dual-site fluorescent probes for simultaneously detecting active molecules and polarity.

Diversity of fungal assemblages in rhizosphere and endosphere of blueberry (Vaccinium spp.) under field conditions revealed by culturing and culture-independent molecular methods.

Mycorrhizae are important to plants in improving nutrient absorption and stress resistance. To study mycorrhizal fungal diversity in blueberry, we combined culture method and culture-independent molecular method to analyze the root endosphere and rhizosphere fungi in three different cultivars. We obtained 212 isolates with a culture method and classified them into 40 types according to their morphological characteristics. Then, we amplified the internal transcribed spacer sequence and found rich species diversity. With high-throughput sequencing, 561 operational taxonomic units (OTUs) were annotated based on a 97% similarity level cutoff. The alpha diversity index revealed that the fungal abundance and diversity in the rhizosphere were higher than those in the endosphere. The dominant phyla were Ascomycota and Basidiomycota and the dominant genus was Oidiodendron. We also constructed the plant-fungus symbiotic system by inoculating in vitro stock shoots, which lays a theoretical foundation for further research to develop and utilize the dominant mycorrhizal fungi of blueberry.

Bacillus subtilis revives conventional antibiotics against Staphylococcus aureus osteomyelitis.

As treatment of Staphylococcus aureus (S. aureus) osteomyelitis is often hindered by the development of antibiotic tolerance, novel antibacterial therapeutics are required. Here we found that the cell-free supernatant of Bacillus subtilis (B. subtilis CFS) killed planktonic and biofilm S. aureus, and increased S. aureus susceptibility to penicillin and gentamicin as well. Further study showed that B. subtilis CFS suppressed the expression of the genes involved in adhesive molecules (Cna and ClfA), virulence factor Hla, quorum sensing (argA, argB and RNAIII) and biofilm formation (Ica and sarA) in S. aureus. Additionally, our data showed that B. subtilis CFS changed the membrane components and increased membrane permeabilization of S. aureus. Finally, we demonstrated that B. subtilis CFS increased considerably the susceptibility of S. aureus to penicillin and effectively reduced S. aureus burdens in a mouse model of implant-associated osteomyelitis. These findings support that B. subtilis CFS may be a potential resistance-modifying agent for ß-lactam antibiotics against S. aureus.

Natural polyketide 6-pentyl-2H-pyrone-2-one and its synthetic analogues efficiently prevent marine biofouling.

Biofouling is a widespread phenomenon in oceans worldwide. With increasing human development and activities in open and coastal waters, and due to the environmental impact of AF organotins and copper-based paint, the demand for nontoxic antifouling (AF) paints is increasing. Various bioassays for antimicrobial activity, anti-biofilm formation and anti-barnacle settlement were established to evaluate the possibility of using marine natural products as AF agents. A series of natural products, isolated from the marine-derived fungi Trichoderma atroviride and T. reesei, were evaluated for their AF activity. One pyrone-type compound (1) demonstrated significant inhibitory activities toward barnacle cyprid settlement. Furthermore, a series of pyrone analogues (S1-S6) were synthesized, and their bioactivities were evaluated in the established systems. The results showed that compounds S5 and S6 exhibited a broad spectrum of bioactivities, such as anti-barnacle settlement, anti-biofilm formation and antimicrobial activities.

Biomimetic mineralisation systems for in situ enamel restoration inspired by amelogenesis.

Caries and dental erosion are common oral diseases. Traditional treatments involve the mechanical removal of decay and filling but these methods are not suitable for cases involving large-scale enamel erosion, such as hypoplasia. To develop a noninvasive treatment, promoting remineralisation in the early stage of caries is of considerable clinical significance. Therefore, biomimetic mineralisation is an ideal approach for restoring enamel. Biomimetic mineralisation forms a new mineral layer that is tightly attached to the surface of the enamel. This review details the state-of-art achievements on the application of amelogenin and non-amelogenin, amorphous calcium phosphate, ions flow and other techniques in the biomimetic mineralisation of enamel. The ultimate goal of this review was to shed light on the requirements for enamel biomineralisation. Hence, herein, we summarise two strategies of biological minimisation systems for in situ enamel restoration inspired by amelogenesis that have been developed in recent years and compare their advantages and disadvantages.

Malunited calcaneal fracture: the role and technique of osteotomy-a systematic review.

PURPOSE: The research is aimed to introduce various corrective osteotomies utilized in treating calcaneal malunions in published papers, to further analyze the results, and to summarize recommended indications. METHODS: The relevant research screening was conducted on the following search engines: the Cochrane Library, Web of Science, PubMed, Embase, Medline, and Academic Search Premier. Key words input included "calcaneal/calcaneus", "malunion," and "malunited fracture(s)" with Boolean operators "AND" and "OR." The inclusion criteria were researches containing surgical procedures treating calcaneal malunion with corrective osteotomy and published in the English language. For included research article, such information was extracted and analyzed: the type of calcaneal malunion, the time from initial injury to corrective surgery, the method of osteotomy, outcomes of each osteotomy (score systems, Bohler angle, talocalcaneal height and width of calcaneus, etc.), the function of the affected limb, post-operative complications, and patients' satisfaction. For included review, descriptive, commentary, or indicative sentences about corrective osteotomy were highlighted, analyzed, and summarized. RESULTS: Ten research articles (170 patients with 184 feet) and nine reviews were included in this review, presenting seven types of corrective osteotomies (lateral wall exostectomy, Dwyer osteotomy, lateral wedge opening osteotomy, Romash osteotomy, tongue osteotomy, sagittal resection osteotomy, and modified Dwyer osteotomy). CONCLUSION: A different corrective osteotomy with/without arthrodesis is recommended to be utilized based on the classification of the malunion and the condition of the cartilage in treating malunited calcaneal fractures. With adequate postoperative care and rehabilitation, the results of treatment could be associated with patients' satisfaction and good function.

A Subpopulation of Foxj1-Expressing, Nonmyelinating Schwann Cells of the Peripheral Nervous System Contribute to Schwann Cell Remyelination in the Central Nervous System.

New myelin sheaths can be restored to demyelinated axons in a spontaneous regenerative process called remyelination. In general, new myelin sheaths are made by oligodendrocytes newly generated from a widespread population of adult CNS progenitors called oligodendrocyte progenitor cells (OPCs). New myelin in CNS remyelination in both experimental models and clinical diseases can also be generated by Schwann cells (SCs), the myelin-forming cells of the PNS. Fate-mapping studies have shown that SCs contributing to remyelination in the CNS are often derived from OPCs and appear not to be derived from myelinating SCs from the PNS. In this study, we address whether CNS remyelinating SCs can also be generated from PNS-derived cells other than myelinating SCs. Using a genetic fate-mapping approach, we have found that a subpopulation of nonmyelinating SCs identified by the expression of the transcription factor Foxj1 also contribute to CNS SC remyelination, as well as to remyelination in the PNS. We also find that the ependymal cells lining the central canal of the spinal cord, which also express Foxj1, do not generate cells that contribute to CNS remyelination. These findings therefore identify a previously unrecognized population of PNS glia that can participate in the regeneration of new myelin sheaths following CNS demyelination.SIGNIFICANCE STATEMENT Remyelination failure in chronic demyelinating diseases such as multiple sclerosis drives the current quest for developing means by which remyelination in CNS can be enhanced therapeutically. Critical to this endeavor is the need to understand the mechanisms of remyelination, including the nature and identity of the cells capable of generating new myelin sheath-forming cells. Here, we report a previously unrecognized subpopulation of nonmyelinating Schwann cells (SCs) in the PNS, identified by the expression of the transcription factor Foxj1, which can give rise to SCs that are capable of remyelinating both PNS and CNS axons. These cells therefore represent a new cellular target for myelin regenerative strategies for the treatment of CNS disorders characterized by persistent demyelination.

miR-193a inhibits osteogenic differentiation of bone marrow-derived stroma cell via targeting HMGB1.

BACKGROUND: miR-193a has been shown to be involved in a variety of biological processes, including cell proliferation, differentiation, and apoptosis. However, little is known about how miR-193a regulates osteogenic differentiation. METHODS: We employed RT-qPCR to determine the level of miR-193a and mRNA level of HMGB1 and osteoblast-specific markers (Runx2, ALP, OSX, OCN). Besides, westernblot was used to probe protein level of phosphorylated MAPK family members and ß-catenin. Bioinformatic analysis was used to predict the putative binding sequence of miR-193a to the 3'-UTR of HMGB1 and we confirmed this result by dual luciferase reporter assay. Alizarin red staining assay (ARS) and alkaline phosphatase activity (ALP) were performed to detect osteogenic differentiation. RESULTS: miR-193a was downregulated in OM (osteogenic medium)induced hBMSC. More interestingly, we found that miR-193a mimic attenuated matrix mineralization and alkaline phosphatase activity, whereas miR-193a inhibitor exerted the opposite phenotypes. Mechanistically, we observed that miR-193a played an inhibitory role in expression of osteoblast-specific markers and activation of MAPK and Wnt signaling pathways. Bioinformatic analysis and dual luciferase assay demonstrated that miR-193a directly targeted 3'-UTR of HMGB1. Furthermore, we overexpressed HMGB1 in miR-193a overexpressed hBMSC to establish that HMGB1 acted as downstream target of miR-193a-inhibited osteogenic differentiation. CONCLUSIONS: Here, we reveal miR-193a plays a suppressive role in osteogenic differentiation of hBMSC via targeting HMGB1. These findings provide a novel mechanism underlying osteogenic differentiation and offer therapeutical strategy for bone formation.

Zinc Prevents the Development of Diabetic Cardiomyopathy in db/db Mice.

Diabetic cardiomyopathy (DCM) is highly prevalent in type 2 diabetes (T2DM) patients. Zinc is an important essential trace metal, whose deficiency is associated with various chronic ailments, including vascular diseases. We assessed T2DM B6.BKS(D)-Leprdb/J (db/db) mice fed for six months on a normal diet containing three zinc levels (deficient, adequate, and supplemented), to explore the role of zinc in DCM development and progression. Cardiac function, reflected by ejection fraction, was significantly decreased, along with increased left ventricle mass and heart weight to tibial length ratio, in db/db mice. As a molecular cardiac hypertrophy marker, atrial natriuretic peptide levels were also significantly increased. Cardiac dysfunction and hypertrophy were accompanied by significantly increased fibrotic (elevated collagen accumulation as well as transforming growth factor ß and connective tissue growth factor levels) and inflammatory (enhanced expression of tumor necrosis factor alpha, interleukin-1ß, caspase recruitment domain family member 9, and B-cell lymphoma/leukemia 10, and activated p38 mitogen-activated protein kinase) responses in the heart. All these diabetic effects were exacerbated by zinc deficiency, and not affected by zinc supplementation, respectively. Mechanistically, oxidative stress and damage, mirrored by the accumulation of 3-nitrotyrosine and 4-hydroxy-2-nonenal, was significantly increased along with significantly decreased expression of Nrf2 and its downstream antioxidants (NQO-1 and catalase). This was also exacerbated by zinc deficiency in the db/db mouse heart. These results suggested that zinc deficiency promotes the development and progression of DCM in T2DM db/db mice. The exacerbated effects by zinc deficiency on the heart of db/db mice may be related to further suppression of Nrf2 expression and function.

Sox2 Sustains Recruitment of Oligodendrocyte Progenitor Cells following CNS Demyelination and Primes Them for Differentiation during Remyelination.

The Sox family of transcription factors have been widely studied in the context of oligodendrocyte development. However, comparatively little is known about the role of Sox2, especially during CNS remyelination. Here we show that the expression of Sox2 occurs in oligodendrocyte progenitor cells (OPCs) in rodent models during myelination and in activated adult OPCs responding to demyelination, and is also detected in multiple sclerosis lesions. In normal adult white matter of both mice and rats, it is neither expressed by adult OPCs nor by oligodendrocytes (although it is expressed by a subpopulation of adult astrocytes). Overexpression of Sox2 in rat OPCs in vitro maintains the cells in a proliferative state and inhibits differentiation, while Sox2 knockout results in decreased OPC proliferation and survival, suggesting that Sox2 contributes to the expansion of OPCs during the recruitment phase of remyelination. Loss of function in cultured mouse OPCs also results in an impaired ability to undergo normal differentiation in response to differentiation signals, suggesting that Sox2 expression in activated OPCs also primes these cells to eventually undergo differentiation. In vivo studies on remyelination following experimental toxin-induced demyelination in mice with inducible loss of Sox2 revealed impaired remyelination, which was largely due to a profound attenuation of OPC recruitment and likely also due to impaired differentiation. Our results reveal a key role of Sox2 expression in OPCs responding to demyelination, enabling them to effectively contribute to remyelination. SIGNIFICANCE STATEMENT: Understanding the mechanisms of CNS remyelination is central to developing effective means by which this process can be therapeutically enhanced in chronic demyelinating diseases such as multiple sclerosis. In this study, we describe the role of Sox2, a transcription factor widely implicated in stem cell biology, in CNS myelination and remyelination. We show how Sox2 is expressed in oligodendrocyte progenitor cells (OPCs) preparing to undergo differentiation, allowing them to undergo proliferation and priming them for subsequent differentiation. Although Sox2 is unlikely to be a direct therapeutic target, these data nevertheless provide more information on how OPC differentiation is controlled and therefore enriches our understanding of this important CNS regenerative process.

Is surgical treatment better than conservative treatment for primary patellar dislocations? A meta-analysis of randomized controlled trials.

BACKGROUND: Despite several randomized controlled trials comparing operative to nonoperative management of primary patellar dislocation, the optimal management of this condition remains a subject of controversy. The aim of this study was to compare surgical to conservative treatment of outcomes for primary patellar dislocation by meta-analysis all the relative randomized controlled trials. STUDY DESIGN: Meta-analysis. METHODS: After searching multiple online databases (MEDILINE, EMBASE, CLINICAL, OVID, BISOS and Cochrane registry of controlled clinical trials), eight randomized controlled trials including 430 patients were meta-analyzed in which operative treatment was compared with non-operative treatment for primary patellar dislocation. Outcomes evaluated were redislocation rate, Kujala score, episode of instability, Tegner activity score, Hughston visual analog score (VAS) and patient satisfaction. RESULTS: Outcomes on recurrent patellar dislocation (P = 0.004) and Hughston VAS (P = 0.03) were statistically significant in favor of operative management. Tegner activity score (P < 0.00001) was significantly higher in favor of conservative treatment, though only a few studies were identified. There was no significant difference between the two treatments regarding episode of instability (P = 0.41), Kujala score (P = 0.32) or patient satisfaction (P = 0.49). CONCLUSION: Surgical treatment may be better than conservative treatment for patients with primary patellar dislocation on incidence of redislocation. However, since these findings are built on a limited number of studies available, well-designed, multicenter clinical trials with long-term follow-up are required to provide more solid evidence concerning optimal strategies.

Modified photoanode by in situ growth of covalent organic frameworks on BiVO4 for oxygen evolution reaction.

The development of efficient oxygen evolution reaction (OER) catalysts is of great significance because the water oxidation reaction at the photoanode is the rate-determining step in photoelectrocatalytic (PEC) water splitting. Herein, two hybrid photoanodes named BiVO4/COF-Azo and BiVO4/COF-Ben were prepared by in situ solvothermal growth on a modified BiVO4 photoanode. Characterization results revealed that the Azo and Ben COFs could match with BiVO4 well to form heterojunctions, which could effectively enhance the separation efficiency of photogenerated carriers. Also, the smaller impedance of the composite photoanodes and faster kinetics of the water oxidation reaction promoted the charge transmission and enhanced the reaction efficiency of the surface-reaching holes, respectively. As a result, the composite photoanodes exhibited a larger photocurrent and more negative onset potential compared to the pristine BiVO4. This work not only provides a new strategy to construct efficient hybrid photoanodes, but also expands the applications of COFs.