Ruthenium red alleviates post-resuscitation myocardial dysfunction by upregulating mitophagy through inhibition of USP33 in a cardiac arrest rat model.

Cardiac arrest (CA) remains a leading cause of death, with suboptimal survival rates despite efforts involving cardiopulmonary resuscitation and advanced life-support technology. Post-resuscitation myocardial dysfunction (PRMD) is an important determinant of patient outcomes. Myocardial ischemia/reperfusion injury underlies this dysfunction. Previous reports have shown that ruthenium red (RR) has a protective effect against cardiac ischemia-reperfusion injury; however, its precise mechanism of action in PRMD remains unclear. This study investigated the effects of RR on PRMD and analyzed its underlying mechanisms. Ventricular fibrillation was induced in rats, which were then subjected to cardiopulmonary resuscitation to establish an experimental CA model. At the onset of return of spontaneous circulation, RR (2.5 mg/kg) was administered intraperitoneally. Our study showed that RR improved myocardial function and reduced the production of oxidative stress markers such as malondialdehyde (MDA), glutathione peroxidase (GSSG), and reactive oxygen species (ROS) production. RR also helped maintain mitochondrial structure and increased ATP and GTP levels. Additionally, RR effectively attenuated myocardial apoptosis. Furthermore, we observed downregulation of proteins closely related to mitophagy, including ubiquitin-specific protease 33 (USP33) and P62, whereas LC3B (microtubule-associated protein light chain 3B) was upregulated. The upregulation of mitophagy may play a critical role in reducing myocardial injury. These results demonstrate that RR may attenuate PRMD by promoting mitophagy through the inhibition of USP33. These effects are likely mediated through diverse mechanisms, including antioxidant activity, apoptosis suppression, and preservation of mitochondrial integrity and energy metabolism. Consequently, RR has emerged as a promising therapeutic approach for addressing post-resuscitation myocardial dysfunction.

High value-added utilization of desulfurized building gypsum as self-leveling mortar: the comprehensive effect of cement.

The utilization of desulfurized building gypsum as raw material for gypsum-based self-leveling mortar (GSL) is limited by its low strength and poor water resistance. The objective of this study is to enhance comprehensive properties of GSL and prepare qualified desulfurized building gypsum-based self-leveling mortar that can be effectively applied in practical engineering projects. The influence of cement on water consumption rate of initial fluidity (W/M ratio), fluidity, setting time, mechanical strength, and water resistance of GSL were evaluated. Additionally, rheological parameter, heat of hydration, crystal morphology, and pore structure were also analyzed. Cement significantly improved the fluidity of slurry. Moreover, the compressive strength and softening coefficient of GSL reached 20.6 MPa and 0.56 at 10% cement, respectively. Furthermore, cement reduced the 30-min-fluidity loss and improved fludity by reducing the yield stress and increasing the plastic viscosity of screed. The transformation of hydration kinetics of GSL could be due to Ca2+ and OH- released by cement, thus resulting in the shortening of initial setting time and the prolongation of the interval between initial and final setting time. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) showed that CSH gel and AFt crystal would generate on the surface of CaSO4·2H2O crystal, making the structure more compact. Mercury intrusion porosimetry (MIP) indicated that cement greatly reduced the porosity through the water reduction effect in the early stage and continuous hydration in the later stage. The continuous hydration of cement also increased the shrinkage rate. This work was expected to provide reference for promoting the application of desulfurized building gypsum as the high value-added screed.

Stereo-complex polylactide composite aerogel for crude oil adsorption.

Adsorption materials are a cost-effective and simple method for oil spill remediation, but their efficiency is limited by high crude oil viscosity. Additionally, non-degradable materials pose another risk of secondary pollution, such as microplastic debris. Here, an environmentally-friendly stereo-complex polylactide composite (SCC) aerogel were developed via water-assisted thermally induced phase separation. The SCC with 3 wt% carbon nanotubes had a hierarchical structure of micro/nanoscale pores and high content of stereo-complex crystallites (35.7 %). Along with the excellent water repellency (water contact angle: 157°), SCC aerogel was 2.7 times as resistant to hydrolysis than poly(l-lactide) aerogel (Ph = 13, 37 °C). Additionally, a maximum absorption capacity of 41.2 g g-1 and over 97 % oil/water separation efficiency after 10 cycles were obtained in low viscosity conditions; while in high viscosity conditions, it displayed excellent photothermal performance, reaching a surface temperature of 85 °C under 1 sunlight, reducing crude oil absorption time from 42 min to 60 s (97.6 %-time savings). Moreover, it facilitated continuous crude oil spill recovery under sunlight with an adsorption rate of 3.3 × 104 kg m-3 h-1. The SCC aerogel presents a potential route for utilizing solar energy in crude oil adsorption applications without additional environmental burden.

Growth "self-inhibition" of irbesartan desmotrope: surface intra-annular tautomer inter-conversion is the culprit.

The newly discovered growth self-inhibition phenomenon of tautomeric crystals is now generalized to the demostrope (form B) of irbesartan that displays intra-annular tautomerism in neutral aqueous solutions. The dynamic intra-annular tautomer inter-conversion on the surface is the key factor. Our findings provide implications for producing and engineering tautomeric materials.

Risk factors associated with low-grade virulent infection in intervertebral disc degeneration: a systematic review and meta-analysis.

BACKGROUND: An increasing number of research indicates an association between low-grade bacterial infections, particularly those caused by Propionibacterium acnes (P. acnes), and the development of intervertebral disc degeneration (IDD). However, no previous meta-analysis has systematically assessed the risk factors for low-grade bacterial infections that cause IDD. PURPOSE: This study reviewed the literature to evaluate the risk factors associated with low-grade bacterial infection in patients with IDD. STUDY DESIGN: Systematic review and meta-analysis. METHODS: The systematic literature review was conducted using the PubMed, Web of Science, Embase, and Cochrane Library databases. Eligible articles explicitly identified the risk factors for low-grade bacterial infections in IDD patients. Patient demographics and total bacterial infection rates were extracted from each study. Meta-analysis was performed using random- or fixed-effects models, with statistical analyses conducted using Review Manager (RevMan) 5.4 software.aut. RESULTS: Thirty-three studies involving 4,109 patients were included in the meta-analysis. The overall pooled low-grade bacterial infection rate was 30% (range, 24%-37%), with P. acnes accounting for 25% (range, 19%-31%). P. acnes constituted 66.7% of bacteria-positive discs. Fourteen risk factors were identified, of which 8 were quantitatively explored. Strong evidence supported male sex (odds ratio [OR] = 2.15; 95% confidence interval [CI]=1.65-2.79; p<.00001) and Modic changes (MCs) (OR=3.59; 95% CI=1.68-7.76; p=.0009); moderate evidence of sciatica (OR=2.31; 95% CI=1.33-4.00; p=.003) and younger age (OR=-3.47; 95% CI=-6.42 to -0.53; p=.02). No evidence supported previous disc surgery, MC type, Pfirrmann grade, smoking, or diabetes being risk factors for low-grade bacterial infections in patients with IDD. CONCLUSIONS: Current evidence highlights a significant association between IDD and low-grade bacterial infections, predominantly P. acnes being the most common causative agent. Risk factors associated with low-grade bacterial infections in IDD include male sex, MCs, sciatica, and younger age.

Research prospects for kidney xenotransplantation: a bibliometric analysis.

BACKGROUND: Xenograft kidney transplantation has been receiving increasing attention. The purpose of this study is to use bibliometric analysis to identify papers in this research field and explore their current status and development trends. METHODS: Using the data in the Web of Science core database from Clarivate Analytics as the object of study, we used 'TS = Kidney OR Renal AND xenotransplantation' as the search term to find all literature from 1980 to 2 November 2022. RESULTS: In total, 1005 articles were included. The United States has the highest number of publications and has made significant contributions in this field. Harvard University was at the forefront of this study. Professor Cooper has published 114 articles in this field. Xenotransplantation has the largest number of relevant articles. Transplantation was the most cited journal. High-frequency keywords illustrated the current state of development and future trends in xenotransplantation. The use of transgenic pigs and the development of coordinated co-stimulatory blockers have greatly facilitated progress in xenotransplantation research. We found that 'co-stimulation blockade', 'xenograft survival', 'pluripotent stem cell', 'translational research', and 'genetic engineering' were likely to be the focus of attention in the coming years. CONCLUSIONS: This study screened global publications related to xenogeneic kidney transplantation; analyzed their literature metrology characteristics; identified the most cited articles in the research field; understood the current situation, hot spots, and trends of global research; and provided future development directions for researchers and practitioners.

Whole-lesion iodine map histogram analysis versus single-slice spectral CT parameters for determining novel International Association for the Study of Lung Cancer grade of invasive non-mucinous pulmonary adenocarcinomas.

PURPOSE: The purpose of this study was to evaluate and compare the performances of whole-lesion iodine map histogram analysis to those of single-slice spectral computed tomography (CT) parameters in discriminating between low-to-moderate grade invasive non-mucinous pulmonary adenocarcinoma (INMA) and high-grade INMA according to the novel International Association for the Study of Lung Cancer grading system of INMA. MATERIALS AND METHODS: Sixty-one patients with INMA (34 with low-to-moderate grade [i.e., grade I and grade II] and 27 with high grade [i.e., grade III]) were evaluated with spectral CT. There were 28 men and 33 women, with a mean age of 56.4 ± 10.5 (standard deviation) years (range: 29-78 years). The whole-lesion iodine map histogram parameters (mean, standard deviation, variance, skewness, kurtosis, entropy, and 1st, 10th, 25th, 50th, 75th, 90th, and 99th percentile) were measured for each INMA. In other sessions, by placing regions of interest at representative levels of the tumor and normalizing them, spectral CT parameters (iodine concentration and normalized iodine concentration) were obtained. Discriminating capabilities of spectral CT and histogram parameters were assessed and compared using area under the ROC curve (AUC) and logistic regression models. RESULTS: The 1st, 10th, and 25th percentiles of the iodine map histogram analysis, and iodine concentration and normalized iodine concentration of single-slice spectral CT parameters were significantly different between high-grade and low-to-moderate grade INMAs (P < 0.001 to P = 0.002). The 1st percentile of histogram parameters (AUC, 0.84; 95% confidence interval [CI]: 0.73-0.92) and iodine concentration (AUC, 0.78; 95% CI: 0.66-0.88) from single-slice spectral CT parameters had the best performance for discriminating between high-grade and low-to-moderate grade INMAs. At ROC curve analysis no significant differences in AUC were found between histogram parameters (AUC = 0.86; 95% CI: 0.74-0.93) and spectral CT parameters (AUC = 0.81; 95% CI: 0.74-0.93) (P = 0.60). CONCLUSION: Both whole-lesion iodine map histogram analysis and single-slice spectral CT parameters help discriminate between low-to-moderate grade and high-grade INMAs according to the novel International Association for the Study of Lung Cancer grading system, with no differences in diagnostic performances.

[Research progress of optical motion capture technology in shoulder biomechanics].

The shoulder joint is the most flexible joint in the body with the largest range of motion, and the movement pattern is more complex. Accurate capture of three-dimensional motion data of the shoulder joint is crucial for biomechanical evaluation. Optical motion capture systems offer a non-invasive and radiation-free method to capture shoulder joint motion data during complex movements, enabling further biomechanical analysis of the shoulder joint. This review provides a comprehensive overview of optical motion capture technology in the context of shoulder joint movement, including measurement principles, data processing methods to reduce artifacts from skin and soft tissues, factors influencing measurement results, and applications in shoulder joint disorders.

Deciphering the Effects of Molecular Dipole Moments on the Photovoltaic Performance of Organic Solar Cells.

The dielectronic constant of organic semiconductor materials is directly related to its molecule dipole moment, which can be used to guide the design of high-performance organic photovoltaic materials. Herein, two isomeric small molecule acceptors, ANDT-2F and CNDT-2F, are designed and synthesized by using the electron localization effect of alkoxy in different positions of naphthalene. It is found that the axisymmetric ANDT-2F exhibits a larger dipole moment, which can improve exciton dissociation and charge generation efficiencies due to the strong intramolecular charge transfer effect, resulting in the higher photovoltaic performance of devices. Moreover, PBDB-T:ANDT-2F blend film exhibits larger and more balanced hole and electron mobility as well as nanoscale phase separation due to the favorable miscibility. As a result, the optimized device based on axisymmetric ANDT-2F shows a JSC of 21.30 mA cm-2 , an FF of 66.21%, and a power conversion energy of 12.13%, higher than that of centrosymmetric CNDT-2F-based device. This work provides important implications for designing and synthesizing efficient organic photovoltaic materials by tuning their dipole moment.

Trends and prospects in spinal tuberculosis research: a future-oriented approach.

PURPOSE: Tuberculosis is one of the oldest diseases in human history, and spinal tuberculosis (STB) is the most common form of extrapulmonary tuberculosis. A large number of research has been conducted in this field. However, there has been no bibliometric analysis performed in recent years in STB. The aim of this study was to analyze trends and hotspots in research on STB. METHODS: Publications regarding STB between 1980 and 2022 were extracted from the Web of Science database. CiteSpace (V5.7.R2) and VOSviewer (1.6.10) were used to perform global analyses of the number of publications, countries, institutions, authors, journals, keywords, and cited references. RESULTS: A total of 1262 articles were published between 1980 and 2022. We observed rapid growth in the number of publications since 2010. Spine had the highest number of publications (47, 3.7%). Zhang HQ and Wang XY were key researchers. The Central South University published the most papers (90, 7.1%). China was the leading contributor in this field with 459 publications and 29 H-index. National partnerships are dominated by the USA, and there is a lack of active cooperation between other countries and authors. CONCLUSION: research on STB has achieved great progress, with an increasing number of publications since 2010. Surgical treatment and debridement are current research hots pots, and diagnosis, drug resistance, and kyphosis are likely research frontiers. Cooperation between countries and authors needs to be further strengthened.

Does the Fatty Infiltration Influence the Re-tear Rate and Functional Outcome After Rotator Cuff Repair? A Systematic Review and Meta-analysis.

Purpose: Fatty infiltration (FI) of the rotator cuff muscles occurs after rotator cuff tears (RCTs), which may affect the outcome of the repair procedure. This study aimed to determine the relationship between preoperative FI and the rate of re-tear and functional outcomes after rotator cuff repair. Methods: Computerized databases, including PubMed, EMBASE, Web of Science, and Cochrane Library database were searched for studies published from the inception date to January 2022. Two reviewers independently screened the titles and abstracts using prespecified criteria. Articles were included if they clearly stated the effect of varying degrees of FI on the outcome after shoulder cuff repair. Comparison was performed by different degrees of FI analysis: no FI is grade 0-1, FI is grade 2 and above. Statistical analysis was performed using Review Manager 5.4.1 software. Results: A total of 16 articles involving 1383 patients from 8 countries were included. The follow-up period ranged from 8 to 121 months. In terms of re-tear rate: patients with preoperative FI had significantly higher rates of re-tear compared with patients without FI (OR 4.60, 95% CI 2.22-9.54, p < 0.0001), supraspinatus FI VS no FI (OR 2.06, 95% CI 1.00-4.24, p = 0.05), infraspinatus FI VS no FI (OR 2.42, 95% CI 1.19-4.91, p = 0.01). In terms of functional scoring: patients without FI had higher postoperative Constant-Murley (Constant) scores than those with FI (MD - 5.06, 95% CI - 9.40 to - 0.72, p = 0.02), there was no clear evidence that preoperative FI was related to postoperative American Society of shoulder and elbow physicians scores and the University of California at Los Angeles scores and range of motion. Conclusion: FI after RCTs significantly increases the risk of postoperative re-tear and leads to worse functional scores, especially FI of the infraspinatus muscle. However, FI does not seem to reduce postoperative range of motion. Supplementary Information: The online version contains supplementary material available at 10.1007/s43465-022-00807-0.

[Progress in arthroscopic surgery for injury of superior labrum anterior posterior of shoulder joint].

Superior labrum anterior posterior (SLAP) injury is a major challenge for orthopedic surgeons, due to the poor healing ability of the injured labrum. Although arthroscopic surgery is the gold standard for the treatment of SLAP injury, there are still disputes about the adaptation of different surgical techniques, the choice of anchors during operation, knotted or knotless anchors, and fixation methods. The authors believe that arthroscopic repair of SLAP lesions is effective for young patients with intact glenoid labrum(<35 years old) or with extensive activity, where single and knotless anchor is preferred. For the older patients(≥35 years old) with degeneration and wear of glenoid labrum, biceps tenodesis is more preferable, and interference screw fixation technique is recommended. As for patients with failed SLAP repair, biceps tenodesis can achieve a high success rate as a revision surgery. By review of the relevant literature in recent years, this paper summarizes the adaptation of different surgical methods of arthroscopic treatment of SLAP injury, intraoperative anchoring techniques, fixation methods and other improved surgical techniques.

Circ_0043256 upregulates KLF2 expression by absorbing miR-1206 to suppress the tumorigenesis of lung cancer.

BACKGROUND: Circular RNAs (circRNAs) have been reported to play roles in lung cancer development. The purpose of this work was to explore the function and mechanism of circ_0043256 in lung cancer tumorigenesis. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot were used for the detection of the levels of genes and proteins. Cell growth, angiogenesis ability, migration, and invasion were analyzed by using 5-ethynyl-2'-deoxyuridine (EdU) assay, flow cytometry, tube formation assay, transwell assay, and murine xenograft model, respectively. The target between miR-1206 and circ_0043256 or Krüppel-like factor 2 (KLF2) was verified by dual-luciferase reporter assay. RESULTS: Circ_0043256 was a stable circRNA, which was found to be decreased in lung cancer tissues and cells. Functionally, forced expression of circ_0043256 suppressed lung cancer cell growth, angiopoiesis, migration, and invasion. Mechanistically, circ_0043256 directly bound to miR-1206 and miR-1206 targeted KLF2, circ_0043256 could regulate KLF2 expression via absorbing miR-1206. Rescue assay showed that miR-1206 overexpression reversed the anticancer effects of circ_0043256 on lung cancer cells. Moreover, inhibition of miR-1206 could suppress the malignant phenotypes of lung cancer cells, which was attenuated by KLF2 knockdown. Pre-clinically, lentivirus-mediated circ_0043256 overexpression impeded lung cancer growth in nude mice. CONCLUSION: Forced expression of circ_0043256 could impede the tumorigenesis of lung cancer via miR-1206/KLF2 axis, indicating a potential therapeutic approach for lung cancer.

Combination of autologous osteochondral and periosteum transplantation effectively promotes fibrocartilage regeneration at the tendon-bone junction of the rotator cuff in rabbits.

PURPOSE: Rotator cuff tendon-bone healing often leads to scarring and low biomechanical strength, resulting in a tendency to re-tear. This study examined whether combining autologous osteochondral transplantation and periosteum transplantation increases fibrocartilage transition zone regeneration and improves biomechanical fixation. METHODS: A total of 48 New Zealand white rabbits were divided into the periosteum, autologous osteochondral, combination of autologous osteochondral and periosteum, and control groups. The supraspinatus tendon was cut from the greater tuberosity and repaired by different transplants. A total of 12 rabbits were used for histological examination (haematoxylin and eosin staining, Masson's staining and Safranin-O staining) at 4, 8 and 12 weeks after the repair, and 36 rabbits were used for biomechanical tests (maximal failure load and stiffness). RESULTS: At 4 weeks following the operation, each group had a large tendon-bone gap with a small number of disordered collagen fibres. At 8 weeks, the tendon-bone gap was smaller than that before the operation, and the tendon-bone gap in each experimental group was smaller with neater and denser collagen fibres and chondrocytes than in the control group, with the osteochondral combined periosteum group having the best results. At 12 weeks, the typical tendon-bone transitional structure was observed in the osteochondral combined periosteum group, and more collagen fibres and chondrocytes were generated in each group. The osteochondral combined periosteum group had the largest staining area and the largest amount of cartilage. The maximum tensile strength and stiffness of each group increased over time. There was no significant difference in each group's maximum tensile strength and stiffness at 4 weeks after the operation. However, the maximum tensile strength and stiffness of the osteochondral combined periosteum group at 8 and 12 weeks after operation were significantly higher than those of other groups (P < 0.05). CONCLUSION: Histological and biomechanical results show that autologous osteochondral transplantation combined with periosteum transplantation can effectively promote the regeneration of fibrous cartilage in the tendon-bone junction of the rotator cuff. It is concluded that this technique is a new treatment method to promote tendon-bone healing in the rotator cuff.

BAICALEIN RELIEVES BRAIN INJURY VIA INHIBITING FERROPTOSIS AND ENDOPLASMIC RETICULUM STRESS IN A RAT MODEL OF CARDIAC ARREST.

ABSTRACT: Background: Cardiac arrest (CA) is one of the leading causes of death worldwide. Endoplasmic reticulum (ER) stress and ferroptosis are proven pathological mechanisms implicated in neuronal damage. Baicalein, a ferroptosis Inhibitor, improved outcomes after traumatic brain injury. We aimed to explore the effects of baicalein on brain injury via ferroptosis and ER stress in a rat model of CA.Methods: Cardiac arrest models were established in Sprague-Dawley (SD) rats. The sham group (n = 6) was untreated with inducing ventricular fibrillation to cardiac arrest and cardiopulmonary resuscitation (CPR). Survival rats were randomly divided into five groups (n = 6). Ferroptosis inhibitor and ER stress agonist were administered separately and together in three groups. There was no drug intervention in the remaining group. The neurological deficit scores were recorded. Characteristics of ferroptosis were observed. And the associated protein of ferroptosis and ER stress were determined by Western blot. Cerebral ROS production was measured by using 2',7'-dichlorofluorescein diacetate as the oxidative fluorescent probe. Results: Baicalein treatment improved neurological outcomes and decreased neurocyte injuries compared with CPR group. The changes of ferroptosis, more specifically, iron content, glutathione peroxidase 4 (GPX4), reactive oxygen species (ROS), arachidonate 15-lipoxygenase (ALOX15) and mitochondrial characteristics, were observed in brain tissue after ROSC. ALOX15 was lower in baicalein group than in CPR group. The morphology and structure of mitochondria in baicalein group were better than in CPR group. The ER stress markers, glucose-regulated protein 78, activating Transcription Factor 4 and C/EBP homologous protein was lower in baicalein group compared with CPR group. ROS in tunicamycin group was higher than in CPR group. And ROS in baicalein +tunicamycin group was lower than in tunicamycin group. Conclusion: Ferroptosis and ER stress are both involved in brain injury after ROSC. Baicalein alleviates brain injury via suppressing the ferroptosis and ER stress, and reduces ROS partly through inhibiting ER stress. Baicalein is a potential drug to relieve brain injury after ROSC.

Does the critical shoulder angle influence retear and functional outcome after arthroscopic rotator cuff repair? A systematic review and meta-analysis.

PURPOSE: This systematic review and meta-analysis aimed to evaluate the correlation between increased critical shoulder angle (CSA) and higher retear rates and functional outcomes after arthroscopic rotator cuff repair (ARCR). METHODS: PubMed, Embase, Web of Science, and Cochrane Library databases published before January 2022 were comprehensively searched. Two reviewers independently reviewed the titles and abstracts using the specified criteria. Studies were included if the authors clearly described the correlation between the CSA and rotator cuff repair. Data on patient characteristics, mean CSA, retear rate, and the functional score was pooled from the selected articles. A meta-analysis was performed using Review Manager (RevMan) 5.4.1 software, 2020 (Cochrane Collaboration, Copenhagen, Denmark). RESULTS: Eleven articles involving 1449 patients from 7 countries were included. The ages of the patients ranged from 45 to 75 years. The follow-up period ranged from 6 to 96 months. The mean CSA was greater in the retear group than in the non-retear group after ARCR (mean difference 2.73°; 95% confidence interval [CI] 0.69-4.77) (p = 0.009). Three studies evaluated the association between increased CSA and the postoperative retear rate. All three studies showed a higher postoperative retear rate in patients with an increased CSA (odds ratio 5.35; 95% CI 2.02-14.15; p = 0.0007). No association was found between CSA and Constant-Murley (Constant), the University of California at Los Angeles (UCLA), or Visual Analog Scale (VAS) scores during the follow-up period of 24-96 months (p > 0.05). CONCLUSIONS: This systematic review and meta-analysis showed that CSA correlates highly with rotator cuff retear after ARCR. In addition, the postoperative retear rate of the rotator cuff increased with increased CSA. CSA appeared to not affect worse functional outcomes in patients after ARCR.

[Progress on arthroscopic surgery for massive rotator cuff tears].

The surgical treatment of massive rotator cuff tears is a clinical challenge for orthopaedic surgeons. Moreover, tendon retraction, adhesions and fatty infiltration after rotator cuff tear will further increase the difficulty of surgical repair. Therefore, it has become a hotspot and difficulty to repair massive rotator cuff tears with a better way in current research. In recent years, with the continuous development of arthroscopic techniques, shoulder arthroscopic surgery has become the gold standard for the treatment of massive rotator cuff tears, but the adaptations, effects and combined application of different surgical methods are still controversial. The author believes that arthroscopic debridement of shoulder joint and acromioplasty or tuberoplasty could relieve shoulder pain in the short-term for elderly patients with lower functional requirements;long biceps tenotomy or tenodesis is effective for patients with biceps long head tendon injury; complete repair is still the first line treatment for massive rotator cuff tears, but partial repair is possible for massive rotator cuff tears that could not be completely repaired;patch augmentation technology could bring good results for young patients with high functional requirements;for patients with limited internal and external rotation of the shoulder joint and high functional requirements, tendon transfers surgery is recommended;superior capsular reconstruction is more advantageous for young patients with no obvious glenohumeral arthritis, better deltoid muscle strength and higher functional requirements. In addition, subacromial spacer implantation has become a current research hotspot due to its advantages of small trauma, low cost and relative safety, and its long-term effect still needs to be further confirmed.

A rigid redox-active-ligand-supported bis(germylene) as a two-centre six-electron donor.

A naphthyridine diimine (NDI) supported bis(germylene) NDI-Ge2 containing two dicoordinate, coplanar Ge(II) atoms has been synthesised. Computational investigations on NDI-Ge2 indicated the two Ge(II) atoms are nearly independent. The EDA-NOCV analysis of the [NDI-Ge2][Fe2(CO)6] complex revealed the six-electron donor behavior of NDI-Ge2, the first example for group-14-element-based bidentate ligands.

[Arthroscopic subscapularis augmentation for the treatment of recurrent dislocation of shoulder with severe glenoid injury].

OBJECTIVE: To investigate the method and clinical effects of the treatment of recurrent shoulder dislocation with severe glenoid injury by arthroscopic subscapularis augmentation. METHODS: From March 2019 to August 2020, 16 patients with recurrent dislocation of shoulder with severe glenoid injury underwent arthroscopic subscapularis augmentation, including 10 males and 6 females, aged from 18 to 50 years old with an average of (29.06±10.54) years old, 4 cases of left shoulder and 12 cases of right shoulder.Visual analogue scale (VAS), American Shoulder and Elbow Surgeons (ASES) score and Rowe score were used to evaluate shoulder function and stability before and after operation. RESULTS: All the 16 patients were followed up from 12 to 29 months, with an average of (18.75±7.26) months. VAS score decreased from 5.25±1.13 before operation to 1.37±0.65 at the final follow-up;ASES score increased from 59.44±9.93 before surgery to 90.88±4.00 at the final follow-up; Rowe score of shoulder increased from 51.56±8.89 before surgery to 92.19±7.06 at the final follow-up, and the differences were statistically significant (P<0.05). No dislocation was observed during follow-up. No clinical complications such as incision infection, vascular and nerve injury occurred in all patients after operation. CONCLUSION: Arthroscopic subscapularis augmentation in the treatment of recurrent dislocation of shoulder with severe glenoid injury is satisfactory. It is an effective treatment method of recurrent dislocation of shoulder joint with severe glenoid injury, and external rotation function in patients with almost unaffected.

Investigation of the electronic structural and optical properties of CH3NH3HgI3 crystal.

Based on the first-principles density functional theory, the electronic structure and optical properties of CH3NH3HgI3 crystal were investigated by means of generalized gradient approximation (GGA + U) approach. Then, CH3NH3HgI3 crystal was grown successfully by anti-solvent method, and the UV-vis-NIR spectra of crystal grown were investigated. The results indicate that CH3NH3HgI3 belongs to direct band-gap semiconductor with 2.801 eV of band-gap. The energy level of electrons at the top of the valence band and the bottom of the conduction band is mainly formed by Hg and I, while C, N, and H of CH3NH3+ do not participate in forming the electron configuration near the Fermi level. CH3NH3HgI3 was combined by electrostatic interactions with CH3NH3+ and [HgI4]2-. Their electrostatic interactions lead to distortion of [HgI4]2- tetrahedron and cause the increase of band-gap of CH3NH3HgI3. Moreover, steric hindrance effect of CH3NH3+ spurs [HgI4]2- tetrahedron to form 1D chain structure. The result obtained from the UV-vis-NIR spectra of crystal shows that the band-gap of CH3NH3HgI3 crystal is 2.877 eV, which is good coincident with the calculated gap (2.801 eV). Our discussions on the electronic structural and energy band of crystal suggest that CH3NH3HgI3 can be used as an ultraviolet detector material.