Nickle-cobalt alloy nanocrystals inhibit activation of inflammasomes.

Activation of inflammasomes-immune system receptor sensor complexes that selectively activate inflammatory responses-has been associated with diverse human diseases, and many nanomedicine studies have reported that structurally and chemically diverse inorganic nanomaterials cause excessive inflammasome activation. Here, in stark contrast to reports of other inorganic nanomaterials, we find that nickel-cobalt alloy magnetic nanocrystals (NiCo NCs) actually inhibit activation of NLRP3, NLRC4 and AIM2 inflammasomes. We show that NiCo NCs disrupt the canonical inflammasome ASC speck formation process by downregulating the lncRNA Neat1, and experimentally confirm that the entry of NiCo NCs into cells is required for the observed inhibition of inflammasome activation. Furthermore, we find that NiCo NCs inhibit neutrophil recruitment in an acute peritonitis mouse model and relieve symptoms in a colitis mouse model, again by inhibiting inflammasome activation. Beyond demonstrating a highly surprising and apparently therapeutic impact for an inorganic nanomaterial on inflammatory responses, our work suggests that nickel- and cobalt-containing nanomaterials may offer an opportunity to design anti-inflammatory nanomedicines for the therapeutics of macrophage-mediated diseases.

Gallium nitride catalyzed the direct hydrogenation of carbon dioxide to dimethyl ether as primary product.

The selective hydrogenation of CO2 to value-added chemicals is attractive but still challenged by the high-performance catalyst. In this work, we report that gallium nitride (GaN) catalyzes the direct hydrogenation of CO2 to dimethyl ether (DME) with a CO-free selectivity of about 80%. The activity of GaN for the hydrogenation of CO2 is much higher than that for the hydrogenation of CO although the product distribution is very similar. The steady-state and transient experimental results, spectroscopic studies, and density functional theory calculations rigorously reveal that DME is produced as the primary product via the methyl and formate intermediates, which are formed over different planes of GaN with similar activation energies. This essentially differs from the traditional DME synthesis via the methanol intermediate over a hybrid catalyst. The present work offers a different catalyst capable of the direct hydrogenation of CO2 to DME and thus enriches the chemistry for CO2 transformations.

[Analysis on Polymorphism of Platelet Antigen Gene in Shandong Han Population].

OBJECTIVE: To study the Polymorphism of the human platelet antigen(HPA) gene 1-17 and human leukocyte antigen(HLA) gene-A and B locus in Shandong Han population. METHODS: A total of 962 samples from routine voluntary platelet donors were genotyped for HPA1-17 system and HLA-A site, B by PCR-SSP and PCR-SSOP respectively．Gene frequencies were calculated by counting. HPA1-17 and HLA genotype combinations were analyzed by Arelequin 3.5. RESULTS: The gene frequencies of HPA-la, -1b, HPA-2a, -2b, HPA-3a, -3b, HPA-4a, -4b, HPA-5a, -5b, HPA-6a, -6b, HPA-15a, -15b were 0.9918, 0.0082, 0.9419, 0.0592, 0.5841, 0.4174, 0.9969, 0.0031, 0.9892, 0.0108, 0.9835, 0.0175,0.5488 and 0.4512, respectively． The most common HPA genotype combination was HPA-(1, 2, 4, 5, 6, 7-14, 16, 17) aa-3ab-15ab (0.2048). Moreover, HLA-A*2(0.3094) and HLA-B*13(0.1513) showed the highest frequency in their respective locus. The most common HLA genotype combination was HLA-A*2-B*13(0.1397) . CONCLUSION: Distributions of HPA and HLA show high polymorphism in Shandong Han population. The ethnic and territorial difference of HPA distribution is also confirmed. It is imperative to establish local genetic database of volunteer platelet donors.

Thermoresponsive in Situ Forming Hydrogel with Sol-Gel Irreversibility for Effective Methicillin-Resistant Staphylococcus aureus Infected Wound Healing.

An in situ forming hydrogel has emerged as a promising wound dressing recently. As physically cross-linked hydrogels are normally unstable, most in situ forming hydrogels are chemically cross-linked. However, big concerns have remained regarding the slow gelation and the potential toxicity of residual functional groups from cross-linkers or the polymer matrix. Herein, we report a sprayable in situ forming hydrogel composed of poly(N-isopropylacrylamide166-co-n-butyl acrylate9)-poly(ethylene glycol)-poly(N-isopropylacrylamide166-co-n-butyl acrylate9) copolymer (P(NIPAM166-co-nBA9)-PEG-P(NIPAM166-co-nBA9), denoted as PEP) and silver-nanoparticles-decorated reduced graphene oxide nanosheets (Ag@rGO, denoted as AG) in response to skin temperature. This thermoresponsive hydrogel exhibits intriguing sol-gel irreversibility at low temperatures for the stable dressing of a wound, which is attributed to the inorganic/polymeric dual network and abundant coordination interactions between Ag@rGO nanosheets and PNIPAM. The biocompatibility and antibacterial ability against methicillin-resistant Staphylococcus aureus (MRSA) of this PEP-AG hydrogel wound dressing are confirmed in vitro and in vivo, which could transparently promote the healing of a MRSA-infected skin defect.

MnFe2O4 nanoparticles accelerate the clearance of mutant huntingtin selectively through ubiquitin-proteasome system.

Neurodegenerative disorders such as Huntington's disease (HD) are fundamentally caused by accumulation of misfolded aggregate-prone proteins. Previous investigations have shown that these toxic protein aggregates could be degraded through autophagy induced by small molecules as well as by nanomaterials. However, whether engineered nanomaterials have the capacity to degrade these protein aggregates via the ubiquitin-proteasome system (UPS), the other major pathway for intracellular protein turnover, was unknown. Herein, we have synthesized biocompatible MnFe2O4 nanoparticles (NPs) and demonstrated their unique effect in accelerating the clearance of mutant huntingtin (Htt) protein exhibiting 74 glutamine repeats [Htt(Q74)]. UPS, rather than autophagy, was responsible for the efficient Htt(Q74) degradation facilitated by MnFe2O4 NPs. Meanwhile, we demonstrated that MnFe2O4 NPs enhanced K48-linked ubiquitination of GFP-Htt(Q74). Moreover, ubiqinlin-1, but not p62/SQSTM1, served as the ubiquitin receptor that mediated the enhanced degradation of Htt(Q74) by MnFe2O4 NPs. Our findings may have implications for developing novel nanomedicine for the therapy of HD and other polyglutamine expansion diseases.

Transforming ground mica into high-performance biomimetic polymeric mica film.

Biomimetic assembly of high-quality nanosheets into nacre-like structures can produce macroscopic films with favorable mechanical and optical performances due to the intrinsic properties and high level of ordering of the nanoscale building blocks. Natural ground mica is abundant and exhibits great application potential. However, large size and low aspect ratio greatly limit its biomimetic assembly. Moreover, exfoliation of ground mica into high-quality nanosheets remains a significant challenge. Here, we report that large-scale exfoliation of ground mica into mono- or few-layered mica nanosheets with a production rate of ~1.0 g h-1 can be successfully achieved. The mica nanosheets are then assembled into strong biomimetic polymeric mica film that inherits the high electric insulation, excellent visible transmittance, and unique ultraviolet-shielding properties of natural mica. Its overall performance is superior to that of natural sheet mica and other biomimetic films, making the polymeric mica film a suitable substrate for flexible and transparent devices.

Self-assembled KCu7S4 nanowire monolayers for self-powered near-infrared photodetectors.

Near infrared light (NIR) photodetectors based on one-dimensional semiconductor nanowires have generated considerable interest due to their practical application in versatile fields. We present a facile yet efficient approach to rationally integrating KCu7S4 semiconductor nanowires by the Langmuir-Blodgett (LB) technique. A self-powered near infrared (NIR) light photodetector is fabricated by transferring a close-packed KCu7S4 nanowire monolayer to the surface of a silicon wafer. The as-fabricated Si/KCu7S4 heterojunction with a close-packed and well-aligned nanowire array exhibits splendid photovoltaic performance when illuminated by NIR light, allowing the detection of NIR light without an exterior power supply. The photodetector exhibits a high sensitivity to NIR light (980 nm, 295.3 µW cm-2) with responsivity (R) 15 mA W-1 and detectivity (D*) 2.15 × 1012 cm Hz1/2 W-1. Significantly, the device shows the capability to work under high pulsed light irradiation up to 50 kHz with a high-speed response (response time τr 7.4 µs and recovery time τf 8.6 µs). This facilitates the fabrication of low-cost and high-speed photodetectors and integrated optoelectronic sensor circuitry.

Nacre-mimic Reinforced Ag@reduced Graphene Oxide-Sodium Alginate Composite Film for Wound Healing.

With the emerging of drug-resistant bacterial and fungal pathogens, there raise the interest of utilizing versatile antimicrobial biomaterials to treat the acute wound. Herein, we report the spraying mediated assembly of a bio-inspired Ag@reduced graphene-sodium alginate (AGSA) composite film for effective wound healing. The obtained film displayed lamellar microstructures similar to the typical "brick-and-mortar" structure in nacre. In this nacre-mimic structure, there are abundant interfacial interactions between nanosheets and polymeric matrix, leading to remarkable reinforcement. As a result, the tensile strength, toughness and Young's modulus have been improved 2.8, 2.3 and 2.7 times compared with pure sodium alginate film, respectively. In the wound healing study, the AGSA film showed effective antimicrobial activities towards Pseudomonas aeruginosa, Escherichia coli and Candida albicans, demonstrating the ability of protecting wound from pathogenic microbial infections. Furthermore, in vivo experiments on rats suggested the effect of AGSA film in promoting the recovery of wound sites. According to MTT assays, heamolysis evaluation and in vivo toxicity assessment, the composite film could be applied as a bio-compatible material in vitro and in vivo. Results from this work indicated such AGSA film has promising performance for wound healing and suggested great potential for nacre-mimic biomaterials in tissue engineering applications.

Sequential growth of CaF2:Yb,Er@CaF2:Gd nanoparticles for efficient magnetic resonance angiography and tumor diagnosis.

It is a significant challenge to develop nanoscale magnetic resonance imaging (MRI) contrast agents with high performance of relaxation. In this work, Gd3+-doped CaF2-based core-shell nanoparticles (CaF2:Yb,Er@CaF2:Gd) of sub-10 nm size were controllably synthesized by a facile sequential growth method. The as-prepared hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles modified using PEG-PAA di-block copolymer benefited from the presence of Gd only in the outer CaF2 layer of the nanoparticles, which exhibited r1 as high as 21.86 mM-1 s-1 under 3.0 T, seven times as high as that of commercially used gadopentetate dimeglumine (Gd-DTPA). Low cytotoxicity, no hemolysis phenomenon and no potential gadolinium ion leakage phenomenon of the hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles have been observed and confirmed. Clear vascular details can be observed in magnetic resonance angiography and obvious MR signal of 4T1 tumor area could be significantly improved by intravenous injection of the hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles at a low dosage in mice. A series of in vivo biological safety evaluations confirmed the good biocompatibility of the hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles, which might be employed in clinical blood pool imaging and tumor diagnosis as a safe and efficient MRI probe.

Correlation Between HLA-A, B and DRB1 Alleles and Severe Fever with Thrombocytopenia Syndrome.

OBJECTIVE: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging hemorrhagic fever caused by a tick-borne bunyavirus (SFTSV) in East Asian countries. The role of human leukocyte antigen (HLA) in resistance and susceptibility to SFTSV is not known. We investigated the correlation of HLA locus A, B and DRB1 alleles with the occurrence of SFTS. METHODS: A total of 84 confirmed SFTS patients (patient group) and 501 unrelated non-SFTS patients (healthy individuals as control group) from Shandong Province were genotyped by PCR-sequence specific oligonucleotide probe (PCR-SSOP) for HLA-A, B and DRB1 loci.Allele frequency was calculated and compared using χ2 test or the Fisher's exact test. A corrected P value was calculated with a bonferronis correction. Odds Ratio (OR) and 95% confidence intervals (CI) were calculated by Woolf's method. RESULTS: A total of 11 HLA-A, 23 HLA-B and 12 HLA-DRB1 alleles were identified in the patient group, whereas 15 HLA-A, 30 HLA-B and 13 HLA-DRB1 alleles were detected in the control group. The frequencies of A*30 and B*13 in the SFTS patient group were lower than that in the control group (P = 0.0341 and 0.0085, Pc = 0.5115 and 0.252). The ORs of A*30 and B*13 in the SFTS patient group were 0.54 and 0.49, respectively. The frequency of two-locus haplotype A*30-B*13 was lower in the patient group than in the control group(5.59% versus 12.27%, P = 0.037,OR = 0.41, 95%CI = 0.18-0.96) without significance(Pc>0.05). A*30-B*13-DRB1*07 and A*02-B*15-DRB1*04 had strong associations with SFTS resistance and susceptibility respectively (Pc = 0.0412 and 0.0001,OR = 0.43 and 5.07). CONCLUSION: The host HLA class I polymorphism might play an important role with the occurrence of SFTS. Negative associations were observed with HLA-A*30, HLA-B*13 and Haplotype A*30-B*13, although the associations were not statistically significant. A*30-B*13-DRB1*07 had negative correlation with the occurrence of SFTS; in contrast, haplotype A*02-B*15-DRB1*04 was positively correlated with SFTS.

Purification optimization for a recombinant single-chain variable fragment against type 1 insulin-like growth factor receptor (IGF-1R) by using design of experiment (DoE).

Design of experiment (DoE) is a statistics-based technique for experimental design that could overcome the shortcomings of traditional one-factor-at-a-time (OFAT) approach for protein purification optimization. In this study, a DoE approach was applied for optimizing purification of a recombinant single-chain variable fragment (scFv) against type 1 insulin-like growth factor receptor (IGF-1R) expressed in Escherichia coli. In first capture step using Capto L, a 2-level fractional factorial analysis and successively a central composite circumscribed (CCC) design were used to identify the optimal elution conditions. Two main effects, pH and trehalose, were identified, and high recovery (above 95%) and low aggregates ratio (below 10%) were achieved at the pH range from 2.9 to 3.0 with 32-35% (w/v) trehalose added. In the second step using cation exchange chromatography, an initial screening of media and elution pH and a following CCC design were performed, whereby the optimal selectivity of the scFv was obtained on Capto S at pH near 6.0, and the optimal conditions for fulfilling high DBC and purity were identified as pH range of 5.9-6.1 and loading conductivity range of 5-12.5 mS/cm. Upon a further gel filtration, the final purified scFv with a purity of 98% was obtained. Finally, the optimized conditions were verified by a 20-fold scale-up experiment. The purities and yields of intermediate and final products all fell within the regions predicted by DoE approach, suggesting the robustness of the optimized conditions. We proposed that the DoE approach described here is also applicable in production of other recombinant antibody constructs.

[Identification of a novel HLA allele, HLA-DRB1*03:80, by sequencing-based typing].

This study was aimed to identify a novel HLA-DRB1 allele from a Chinese potential hemopoietic stem cell donor of Northeast China. A rare HLA-DRB1 allele was initially detected by Luminex PCR-SSO typing, then the sample was sequenced by sequence-based typing (SBT) and the alignments of sample's alleles was identified by single allele-specific sequencing strategy. The results revealed the existence of a new allele which differs from the closest matching allele DRB1*03:06 by a single nucleotide substitution at position 239, where C→G in exon 2, resulting in an amino acid exchange from Thr to Arg at codon 51. It is concluded that a novel allele has been confirmed and its name DRB1*03:80 is officially assigned by the WHO Nomenclature Committee in February 2012.

[Identification of a novel HLA allele HLA-B*55:35].

OBJECTIVE: To identify a novel human leukocyte antigen (HLA) B allele and explore its family heritage. METHODS: A novel HLA allele was suspected upon routine HLA typing using a polymerase chain reaction-sequence specific oligonucleotide probe (PCR-SSOP) assay. The sequence was confirmed with DNA sequencing and compared with its closest matching allele, B*55:02. The family was also investigated. RESULTS: An unusual reaction pattern was detected during routine HLA typing. The sequence was confirmed to be a novel HLA-B allele, which differed from the closest matching allele, B*55:02 in 7 nt positions in exon 2. Among the 7 mutations from 6 codons, there were two amino acids changes including 69Glu→Met and 70Glu→Ala. CONCLUSION: A novel HLA-B allele has been identified and officially named as B*55:35 by the WHO Nomenclature Committee for Factors of the HLA System (GenBank accession number FJ898284).

Hydrothermal synthesis of perovskite bismuth ferrite crystallites with the help of NH4Cl.

Bismuth ferrite nanopowders were hydrothermally synthesized with and without NH4Cl for comparison. The effects of NaOH concentration, reaction temperature and reaction time on the product phases and morphologies were studied in detail. Pure BiFeO3 was synthesized in a wide hydrothermal condition with the help of NH4Cl. Especially, it can be synthesized at low temperature of 140 degrees C. X-ray diffraction and Fourier transform infrared spectra revealed the BiFeO3 products had a perovskite structure. Scanning electron microscopy images showed that different BiFeO3 morphologies were formed under different hydrothermal conditions. NH4Cl played a key role in the BiFeO3 formation and BiFeO3 morphologies. Part BiFeO3 samples exhibited weak magnetic properties.

[Identification of a novel HLA allele, HLA-B*35:03:07, by sequencing-based typing].

This study was purposed to analyze and identify a novel HLA allele in Chinese population. A new HLA-B allele which is closely related to HLA-B*35:03:01 was initially detected by PCR-SSOP, then DNA sequencing was performed to identify the difference between the novel allele and HLA-B*35:03:01 allele. The result showed that the sequence of the new allele was different from all other known sequence. It differs from the closest matching HLA-B*35:03:01 by a single substitution at position 387 C→G in exon 3, no resulting in amino acid change. It is concluded that this allele is a novel one and has been officially named B*35:03:07 by the WHO Nomenclature Committee.

[Analysis of HLA-A, B, and DRB1 polymorphism and genetic distance in Han population living in Yantai and Weihai regions of Shandong province].

OBJECTIVE: To investigate allelic and haplotypic polymorphisms of human leukocyte antigen(HLA) genes at A, B and DRB1 loci in Yantai and Weihai Han population and analyze the genetic relationship between Yantai, Weihai Han population and other populations. METHODS: A total of 4062 unrelated Han ethnic individual from Yantai and Weihai regions were genotyped by polymerase chain reaction-sequence specific olignucleotide probe(PCR-SSOP) for HLA-A, B and DRB1 loci. Allelic and haplotypic frequencies were estimated by maximum likelihood estimation method using Arlequin 3.5 software. Genetic distances were computed, and phylogenetic tree was constructed using Mega5.0 software. RESULTS: Respectively 18, 33 and 13 alleles were observed at HLA-A, B and DRB1 loci. The most frequent alleles were HLA-A*02(0.2935), HLA-B*15(0.1485) and HLA-DRB1*15(0.1621). And the most common three loci haplotype was A*30-B*13-DRB1*07(0.0649). A*33-B*58, A*66-DRB1*13 and B*08-DRB1*03 showed the strongest linkage disequilibrium. Yantai and Weihai Han population has the shortest genetic distance with Jilin Han population (0.0034). CONCLUSION: The HLA-A, B and DRB1 loci are highly polymorphic in Han population from Yantai and Weihai, and this population has closest relationship with Han population from Jilin province.

[HLA-A, B and DRB1 polymorphism at high-resolution in Han population from southern area of Shandong province in China].

This study was aimed to analyze the polymorphism of HLA-A, B, DRB1 alleles at high-resolution level in Han population from southern area of Shandong province in China. 688 randomly selected, unrelated and healthy individual from southern area of Shandong province were genotyped for HLA-A, -B and HLA-DRB1 loci by PCR-SBT. Then, allelic and haplotypic distributions of HLA-A, B and DRB1 were estimated by maximum likelihood estimation method using Arlequin 3.0. The results indicated that a total of 31 HLA-A, 63 HLA-B and 39 HLA-DRB1 alleles were identified in Han Population from southern area of Shandong province. Six HLA-A alleles were found with a frequency greater than 0.05 (A*24:02, *30:01, *11:01, *02:01, *33:03 and *02:06), with a cumulative frequency of 0.7223. For HLA-B locus, there were also six alleles which had a frequency higher than 5% (B*1302, *4403, *5101, B*4601, *1501 and *5801), representing 0.4432 of the all alleles in the population. And four HLA-DRB1 alleles were defined as predominant (DRB1*0701, *1501, *0901and *0803), accounting for 0.5453 of the defined alleles. The most common three-loci haplotype was A*30:01-B*13:02-DRB1*07:01 (0.1151) and the most frequent two-loci haplotype were A*30:01-B*13:02 (0.1303), A*30:01-DRB1*07:01 (0.1157) and B*13:02-DRB1*07:01 (0.1307). It is concluded that the allelic and haplotypic diversities of HLA-A, -B and HLA-DRB1 at high-resolution in Han population from southern area of Shandong province in China provide useful information for HLA matching in transplantation and diseases-associated study in this population.

[Identification of a novel HLA allele HLA-B*40:96].

OBJECTIVE: To identify a novel human leukocyte antigen (HLA) allele in Chinese and investigate its inheritance in the family. METHODS: Exceptional reaction pattern was detected in HLA-B locus in HLA typing using Luminex DNA polymerase chain reaction with sequence specific oligonucleotide probe hybridization (PCR-SSOP) assay. A confirmatory test for the novel HLA allele was performed by DNA sequencing based typing of the proband's family. RESULTS: The DNA sequence was confirmed to be a novel HLA B allele. There were 7 nucleotides which differed from the closest matching HLA B*40:06:01 at positions 302(G to A), 309(G to C), 311(A to C), 313(C to G), 314(T to C), 317(G to T), and 319(G to C) in exon 2, which resulted in 5 amino acid changes at codon 101 (Ser to Asn), 104 (Asn to Thr), 105 (Leu to Ala), 106 (Arg to Leu), and 107 (Gly to Arg), respectively. Family investigation indicated that the novel allele was transmitted from the proband's father. CONCLUSION: A novel HLA B allele was identified and officially named as HLA-B*40:96 (GenBank accession No. FJ374890) by the WHO Nomenclature Committee for Factors of the HLA System.

[Identification of a novel allele HLA-DRB1*1219].

OBJECTIVE: To identify a novel HLA DRB1 allele in a Chinese leukemia family. METHODS: A new HLA-DRB1 allele was initially detected by polymerase chain reaction-sequence specific primer and unusual reaction pattern by Luminex RSSO, then DNA sequencing was performed to identify the sequence of the novel allele. RESULTS: The DNA sequencing revealed the presence of the new allele which differs from the closest matching HLA-DRB1*120201 by a single nucleotide substitution at position (341 C > T in exon 2), resulting in an amino acid change from Ala to Val at coden 85. CONCLUSION: A novel allele was confirmed by DNA sequencing and has been designated HLA-DRB1*1219 by the WHO Nomenclature Committee.