(SC,RS)-Bromido-(N-{4-methyl-1-[(4-methyl-phenyl)sul-fan-yl]-pentan-2-yl}-N'-(pyridin-2-yl)imidazol-2-yl-idene)palladium(II) bromide.

The mol-ecule of the title NCNHCS pincer N-heterocyclic carbene palladium(II) complex, [PdBr(C21H25N3S)]Br, exhibits a slightly distorted square-planar coordination at the palladium(II) atom, with the five-membered chelate ring nearly planar. The six-membered chelate ring adopts an envelope conformation. Upon chelation, the sulfur atom becomes a stereogenic centre with an RS configuration induced by the chiral carbon of the precursor imidazolium salt. There are intra-molecular C-H⋯Br-Pd hydrogen bonds in the structure. The two inter-stitial Br atoms, as the counter-anion of the structure, are both located on crystallographic twofold axes and are connected to the complex cations via C-H⋯·Br hydrogen bonds.

BMSC-derived exosomes regulate the Treg/Th17 balance through the miR-21-5p/TLR4/MyD88/NF-κB pathway to alleviate dry eye symptoms in mice.

Bone marrow mesenchymal stem cell (BMSC)-derived exosomes (BMSC-Exos) have a variety of biological functions and are extensively involved in the regulation of inflammatory diseases, as well as tissue repair and regeneration. However, the mechanism of action of these compounds in dry eye disease (DED) in mice is still unclear. This study demonstrated that the Treg/Th17 ratio was strongly imbalanced in DED clinical samples. BMSC-Exos can modulate the Treg/Th17 balance, improve the integrity of the corneal epithelial layer, and ameliorate DED progression in mice. Mechanistically, BMSC-Exos dramatically decreased the levels of IL-17 and IL-22; increased the levels of IL-4, IL-10, and TGF-ß1; and increased tear secretion and the number of goblet cells in the conjunctiva in mice, thus alleviating the progression of DED. This effect is achieved by BMSC-Exos through the delivery of miR-21-5p to target and restrain TLR4, thereby restraining the MyD88/NF-κB pathway. Our study showed that the upregulation of miR-21-5p in BMSC-Exos may be a therapeutic target for DED. These findings support new ideas and a basis for treating DED, as well as for further study of the application value of exosomes in alleviating DED.

Efficacy and Safety of Amniotic Membrane Transplantation Combined with Closure of Tenon Capsule and Bulbar Conjunctival Space in the Treatment of Primary Pterygium.

Objective: The aim of the study is to evaluate the safety and effectiveness of amniotic membrane transplantation combined with the closure of the tenon capsule and bulbar conjunctival space. Methods: This study retrospectively included 100 patients with primary pterygium who received closed bulbar conjunctiva and tenon capsule space combined with amniotic membrane transplantation in our hospital from January 2020 to June 2021 as the experimental group and 100 patients with routine treatment in the same period as the control group. The postoperative efficacy evaluation and postoperative complications of the two groups were compared, so as to comprehensively evaluate the safety and effectiveness of this method. Results: The results showed that the postoperative complications of the two groups were significantly improved by Fisher's exact test (χ 2 = 14.510, P = 0.006 < 0.05). The comparison results showed that the treatment group showed significant advantages in six indexes compared with the observation group and the difference between the two groups was statistically significant (P < 0.05) of in the NRS score, Prabhasawat score, inspection of the ocular surface comprehensive analyzer, corneal fluorescein staining, conjunctival fluorescein staining in the operation area, breakup time of tear film examination of the two groups at 3, 7 and 14 days, and 1, 6 and 12 months after the operation. Conclusions: Amniotic membrane transplantation combined with the closure of the tenon capsule and bulbar conjunctival space is safer than conventional surgery in the treatment of primary pterygium. It has a shorter recovery time, higher safety, and a positive curative effect. It can be considered to popularize this operation in clinic.

Ameliorative Potential of Resveratrol in Dry Eye Disease by Restoring Mitochondrial Function.

Methods: The mitochondrial dysfunction of HCE-2 human corneal epithelial cells was induced by high osmotic pressure exposure and treated with resveratrol (50 µM). Western blotting was used to detect the expression of the antioxidant proteins SOD2, GPx, and SIRT1, and flow cytometry was used to detect cell apoptosis and ROS production. The DED mouse model was induced by 0.2% benzalkonium chloride (BAC) and treated with resveratrol. The tear yield was measured by the phenol cotton thread test, the density of cup cells in the conjunctiva was measured by periodic acid-Schiff (PAS) staining, and the expression levels of SIRT1, GPx, and SOD2 in lacrimal glands were detected by Western blotting. Results: In hypertonic conditions, the apoptosis of HCE-2 cells increased, the expression of the antioxidant proteins SOD2 and GPx decreased, ROS production increased, and the expression of SIRT1 protein, an essential regulator of mitochondrial function, was downregulated. Treatment with resveratrol reversed the mitochondrial dysfunction mediated by high osmotic pressure. In the DED mouse model, resveratrol treatment promoted tear production and goblet cell number in DED mice, decreased corneal fluorescein staining, upregulated SIRT1 expression, and induced SOD2 and GPx expression in DED mice. Conclusion: Resveratrol alleviates mitochondrial dysfunction by promoting SIRT1 expression, thus reducing ocular surface injury in mice with dry eye. This study suggests a new path against DED.

Paralinguistic singing attribute recognition using supervised machine learning for describing the classical tenor solo singing voice in vocal pedagogy.

Humans can recognize someone's identity through their voice and describe the timbral phenomena of voices. Likewise, the singing voice also has timbral phenomena. In vocal pedagogy, vocal teachers listen and then describe the timbral phenomena of their student's singing voice. In this study, in order to enable machines to describe the singing voice from the vocal pedagogy point of view, we perform a task called paralinguistic singing attribute recognition. To achieve this goal, we first construct and publish an open source dataset named Singing Voice Quality and Technique Database (SVQTD) for supervised learning. All the audio clips in SVQTD are downloaded from YouTube and processed by music source separation and silence detection. For annotation, seven paralinguistic singing attributes commonly used in vocal pedagogy are adopted as the labels. Furthermore, to explore the different supervised machine learning algorithm for classifying each paralinguistic singing attribute, we adopt three main frameworks, namely openSMILE features with support vector machine (SF-SVM), end-to-end deep learning (E2EDL), and deep embedding with support vector machine (DE-SVM). Our methods are based on existing frameworks commonly employed in other paralinguistic speech attribute recognition tasks. In SF-SVM, we separately use the feature set of the INTERSPEECH 2009 Challenge and that of the INTERSPEECH 2016 Challenge as the SVM classifier's input. In E2EDL, the end-to-end framework separately utilizes the ResNet and transformer encoder as feature extractors. In particular, to handle two-dimensional spectrogram input for a transformer, we adopt a sliced multi-head self-attention (SMSA) mechanism. In the DE-SVM, we use the representation extracted from the E2EDL model as the input of the SVM classifier. Experimental results on SVQTD show no absolute winner between E2EDL and the DE-SVM, which means that the back-end SVM classifier with the representation learned by E2E as input does not necessarily improve the performance. However, the DE-SVM that utilizes the ResNet as the feature extractor achieves the best average UAR, with an average 16% improvement over that of the SF-SVM with INTERSPEECH's hand-crafted feature set.

[Comparison of techniques irrigating and reversing rabbit ear vein to digest, isolate and culture endothelial cells].

OBJECTIVE: To establish the better method for isolating and culturing the endothelial cells (ECs). METHODS: The "irrigative digestion" and "reverse interiorly-exteriorly digestion" methods were performed for digesting, isolating, collecting and culturing the ear vein endothelial cells of rabbit. The trypan blue stain was used to test the cell activity. The third-passage cell was identified by factor VI related antigen. The differences between the methods in cell number, activity and purity were compared to get an optimal method. RESULTS: The number of ECs deriving from the "irrigative digestion" method had no significant difference from that deriving from the "reverse interiorly-exteriorly" method when cells were isolated from rabbit ear vein originally. However, after cultured for 5 or 10 days, the vein endothelial cells from the "irrigative digestion" method showed the growth status superior to those from the "reverse interiorly-exteriorly" method. The cultured cells had a cobble stone appearance with a strict monolayer growth, it could be observed under inverted microscope. The factor VIII related antigen was tested by immunohistochemistry, it supported that the cultured cells was ECs. CONCLUSION: The "irrigative digestion" method is the better choice to isolate endothelial cells from small vessel.