Publications by authors named "Z B Kang"

1,700 Publications

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Ternary Catalysis Enabled Three-Component Asymmetric Allylic Alkylation as a Concise Track to Chiral α,α-Disubstituted Ketones.

J Am Chem Soc 2021 Dec 6. Epub 2021 Dec 6.

Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.

Multicomponent reactions that involve interception of onium ylides through Aldol, Mannich, and Michael addition with corresponding bench-stable acceptors have demonstrated broad applications in synthetic chemistry. However, because of the high reactivity and transient survival of these generated intermediates, the substitution-type interception process, especially the asymmetric catalytic version, remains hitherto unknown. Herein, a three-component asymmetric allylation of α-diazo carbonyl compounds with alcohols and allyl carbonates is disclosed by employing a ternary cooperative catalysis of achiral Pd-complex, Rh(OAc), and chiral phosphoric acid CPA. This method represents the first example of three-component asymmetric allylic alkylation through an S1-type trapping process, which involves a convergent assembly of two active intermediates, Pd-allyl species, and enol derived from onium ylides, providing an expeditious access to chiral α,α-disubstituted ketones in good to high yields with high to excellent enantioselectivity. Combined experimental and computational studies have shed light on the mechanism of this novel three-component reaction, including the critical role of Xantphos ligand and the origin of enantioselectivity.
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http://dx.doi.org/10.1021/jacs.1c09148DOI Listing
December 2021

Polydopamine Coating-Mediated Immobilization of BMP-2 on Polyethylene Terephthalate-Based Artificial Ligaments for Enhanced Bioactivity.

Front Bioeng Biotechnol 2021 16;9:749221. Epub 2021 Nov 16.

Department of Orthopaedics, Shanghai Pudong Hospital, Fudan University Pudong Medical Center, Shanghai, China.

Polyethylene terephthalate (PET)-based artificial ligaments are one of the most commonly used grafts in anterior cruciate ligament (ACL) reconstruction surgery. However, the lack of favorable hydrophilicity and cell attachment for PET highly impeded its widespread application in clinical practice. Studies found that surface modification on PET materials could enhance the biocompatibility and bioactivity of PET ligaments. In this study, we immobilized bone morphogenetic protein-2 (BMP-2) on the surface of PET ligaments mediated by polydopamine (PDA) coating and investigated the bioactivation and graft-to-bone healing effect of the modified grafts and . In this study, we prepared the PDA coating and subsequent BMP-2-immobilized PET artificial ligaments. Scanning electron microscopy (SEM) was used to analyze the morphological changes of the modified grafts. In addition, the surface wettability properties of the modified ligaments, amount of immobilized BMP 2, and the release of BMP-2 during a dynamic period up to 28 days were tested. Then, the attachment and proliferation of rat bone mesenchymal stem cells (rBMSCs) on grafts were examined by SEM and Cell Counting Kit-8 (CCK-8) assay, respectively. Alkaline phosphatase (ALP) assay, RT-PCR, and Alizarin Red S staining were performed to test the osteoinduction property. For experiments, an extra-articular graft-to-bone healing model in rabbits was established. At 8 weeks after surgery, biomechanical tests, micro-CT, and histological staining were performed on harvested samples. A surface morphological analysis verified the success of the PDA coating. The wettability of the PET artificial ligaments was improved, and more than 80% of BMP-2 stably remained on the graft surface for 28 days. The modified grafts could significantly enhance the proliferation, attachment, as well as expression of ALP and osteogenic-related genes, which demonstrated the favorable bioactivity of the grafts immobilized with BMP-2 . Moreover, the grafts immobilized with BMP-2 at a concentration of 138.4 ± 10.6 ng/cm could highly improve the biomechanical properties, bone regeneration, and healing between grafts and host bone after the implantation into the rabbits compared with the PDA-PET group or the PET group. The immobilization of BMP-2 mediated by polydopamine coating on PET artificial ligament surface could enhance the compatibility and bioactivity of the scaffolds and the graft-to-bone healing .
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http://dx.doi.org/10.3389/fbioe.2021.749221DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8636993PMC
November 2021

TatD DNases Contribute to Biofilm Formation and Virulence in .

Front Microbiol 2021 15;12:758465. Epub 2021 Nov 15.

Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China.

TatD DNases are conserved proteins in a variety of organisms and are considered potential virulence factors in and . However, the function of TatD DNases has not yet been determined in , which causes various infections in animals and leads to economic losses. In this study, we describe the roles of TatD DNases in (TpTatDs). A bioinformatics analysis was performed to investigate the sequence characteristics of TpTatDs, and then the ability of recombinant TatD proteins to hydrolyze DNA was determined in the presence of divalent cations. Moreover, we constructed -deficient mutants. The biofilms formed by the wild-type and mutant strains were observed under a microscope. The mortality and bacterial load in the spleen of mice infected with the wild-type strain and -deficient mutants were determined to obtain insights into the role of TatDs in the virulence of Two TatD DNases were identified in . They were Mg-dependent DNases and exhibited DNA endonuclease activity. Compared with those formed by the parental strain, biofilms formed by mutants showed a significantly reduced thickness and biomass. Moreover, mutants produced a lower bacterial load in the spleen of mice and compromised virulence. Our data indicated that TatD DNases in are involved in biofilm formation and required for virulence during infections.
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http://dx.doi.org/10.3389/fmicb.2021.758465DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8634637PMC
November 2021

Effect of anti-angiotensin II type-1 receptor antibodies on the outcomes of kidney transplantation: a systematic review and meta-analysis.

Nephrol Dial Transplant 2021 Dec 3. Epub 2021 Dec 3.

Department of Blood Transfusion, Tianjin First Central Hospital, 24 Fukang Road, Tianjin, Nankai, China.

Background: Anti-angiotensin II type 1 receptor antibodies (AT1R-Abs) have been recognized as non-HLA antibodies associated with allograft rejection and poor allograft outcomes after kidney transplantation. The aim of this study was to assess the risk anti-AT1R-Abs pose for rejection and graft loss among kidney transplant populations.

Methods: We systematically searched PubMed, EMBASE, and the Cochrane Library databases for relevant articles published from inception until June 2021 to identify all studies concerning the role AT1R-Abs play in the clinical outcome after kidney transplantation. Two reviewers independently identified studies, abstracted outcome data, and assessed the quality of the studies. The meta-analysis was summarized using the fixed-effects models or random-effects models, according to heterogeneity. The major outcomes included delayed graft function, acute rejection, graft loss, or patient death after transplantation.

Results: Twenty-one eligible studies involving a total of 4,023 kidney transplantation recipients were included in the evaluation to identified. Meta-analysis results showed that the AT1R-Ab positive kidney transplant (KT) group had a greater incidence of antibody-mediated rejection (RR = 1.94, 95%CI: 1.61-2.33, P < 0.00001) and graft loss (RR = 2.37, 95%CI: 1.50-3.75, P = 0.0002) than did the AT1R-Abs negative KT group. There was no significant statistical difference in delayed graft function rate, T-cell mediated rejection, mixed rejection, acute cellular rejection, acute rejection, and patient death rate between AT1R-Ab positive KT and AT1R-Ab negative KT groups.

Conclusions: Our study shows that the presence of anti-AT1R-Abs was associated with a significantly higher risk of antibody-mediated rejection and graft loss in kidney transplantation. Future studies are still needed to evaluate the importance of routine anti-AT1R monitoring and therapeutic targeting. These results shows that assessment of anti-AT1R-Abs would be helpful in determining immunologic risk and susceptibility to immunologic events for recipients.
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http://dx.doi.org/10.1093/ndt/gfab344DOI Listing
December 2021

Tough and Degradable Self-Healing Elastomer from Synergistic Soft-Hard Segments Design for Biomechano-Robust Artificial Skin.

ACS Nano 2021 Nov 30. Epub 2021 Nov 30.

Academy for Advanced Interdisciplinary Science and Technology, Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing 100083, People's Republic of China.

Increasing biomechanical applications of skin-inspired devices raise higher requirements for the skin-bionic robustness and environmental compatibility of elastomers. Here, a tough and degradable self-healing elastomer (TDSE) is developed by a synergistic soft-hard segments design. The polyester/polyether copolymer is introduced in soft segments to endow TDSE with flexibility and degradability. The two isomeric diamines are regulated in hard segments for elevating the toughness and fracture energy to 82.38 MJ/m and 43299 J/m and autonomous self-healing ability with 93% efficiency in 7 h for the TDSE. Employing TDSE and ionic liquid, a biomechano-robust artificial skin (BA-skin) is constructed with a stretch-insensitive mechanosensation capability during 50% cyclic stretching. The BA-skin has high biomechano-robustness to bear tear damage and good environmental compatibility with total decomposability in a lipase solution. This work provides a molecular design guideline for high-performance skin-bionic elastomers for applications in skin-inspired devices.
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http://dx.doi.org/10.1021/acsnano.1c09732DOI Listing
November 2021
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