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2.
Inorg Chem ; 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33576224

RESUMO

Although a homometallic (isotopic metal) exchange reaction has been reported, the in-depth understanding of the interaction between a metalloid cluster and the homometal (representing the same metal element as the metalloid cluster) thiolate is quite limited, especially at the atomic level. Herein, based on Ag44(SR)30 (where SR represents 4-mercaptobenzoic acid), we report a facile approach for investigating the metalloid cluster-homometal thiolate interaction at the atomic level, i.e., isotopic exchange in the Ag metalloid cluster. Since such a reaction takes no account of the enthalpy change-related heterometal (representing a different metal element) exchange, the intrinsic metalloid cluster-homometal thiolate interaction can be thoroughly investigated. Through analyzing the ESI-MS (electrospray ionization mass spectrometry) and MS/MS (mass/mass spectrometry) results of the reversible conversion between 107Ag44(SR)30 and 109Ag44(SR)30, we observed that all Ag atoms are exchangeable in the Ag44(SR)30 template. In addition, through analyzing the ESI-MS results of the interconversion between 107Ag29(BDT)12(TPP)4 and 109Ag29(BDT)12(TPP)4, we demonstrated that the metal exchange in the Ag29(BDT)12(TPP)4 metalloid cluster should be a shell → kernel metal transfer process. Our results provide new insights into the metalloid cluster reactivity in the homometal thiolate environment, which will guide the future preparation of metalloid clusters with customized structures and properties.

4.
J Am Chem Soc ; 143(3): 1296-1300, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33433203

RESUMO

Oligonucleotide-based materials such as spherical nucleic acid (SNA) have been reported to exhibit improved penetration through the epidermis and the dermis of the skin upon topical application. Herein, we report a self-assembled, skin-depigmenting SNA structure, which is based upon a bifunctional oligonucleotide amphiphile containing an antisense oligonucleotide and a tyrosinase inhibitor prodrug. The two components work synergistically to increase oligonucleotide cellular uptake, enhance drug solubility, and promote skin penetration. The particles were shown to reduce melanin content in B16F10 melanoma cells and exhibited a potent antimelanogenic effect in an ultraviolet B-induced hyperpigmentation mouse model.

5.
Sensors (Basel) ; 21(3)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499381

RESUMO

The computer vision technique has been rapidly adopted in cow lameness detection research due to its noncontact characteristic and moderate price. This paper attempted to summarize the research progress of computer vision in the detection of lameness. Computer vision lameness detection systems are not popular on farms, and the accuracy and applicability still need to be improved. This paper discusses the problems and development prospects of this technique from three aspects: detection methods, verification methods and application implementation. The paper aims to provide the reader with a summary of the literature and the latest advances in the field of computer vision detection of lameness in dairy cows.

6.
Hum Genet ; 2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33389130

RESUMO

Genetics-associated asthenoteratozoospermia is often seen in patients with multiple morphological abnormalities of the sperm flagella (MMAF). Although 24 causative genes have been identified, these explain only approximately half of patients with MMAF. Since sperm flagella and motile cilia (especially respiratory cilia) have similar axonemal structures, many patients with MMAF also exhibit respiratory symptoms, such as recurrent airway infection, chronic sinusitis, and bronchiectasis, which are frequently associated with primary ciliary dyskinesia (PCD), another recessive disorder. Here, exome sequencing was conducted to evaluate the genetic cause in 53 patients with MMAF and classic PCD/PCD-like symptoms. Two homozygous missense variants and a compound-heterozygous variant in the BRWD1 gene were identified in three unrelated individuals. BRWD1 staining was detected in the whole flagella and respiratory cilia of normal controls but was absent in BRWD1-mutated individuals. Transmission electron microscopy and immunostaining demonstrated that BRWD1 deficiency in human affected respiratory cilia and sperm flagella differently, as the absence of outer and inner dynein arms in sperm flagellum and respiratory cilia, while with a decreased number and outer doublet microtubule defects of respiratory cilia. To our knowledge, this is the first report of a BRWD1-variant-related disease in humans, manifesting as an autosomal recessive form of MMAF and PCD/PCD-like symptoms. Our data provide a basis for further exploring the molecular mechanism of BRWD1 gene during spermatogenesis and ciliogenesis.

7.
Health Phys ; 120(1): 19-23, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32639242

RESUMO

A method that does not require changing wire screens is proposed to achieve continuous measurement of unattached radon progeny. This method uses cumulative activity functions to deduct the influence of previous measurements from the current measurements on the sampling wire screen. The continuous measurement method was compared with a single measurement method, including relative deviations, uncertainties, and fluctuation range, which indicated the effectiveness of the cumulative activity functions applied to the continuous measurement method. The establishment of a continuous measurement method based on alpha spectroscopy provides technical support for the monitoring device.

8.
Poult Sci ; 99(11): 5991-5998, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33142517

RESUMO

Salmonella spp. are important zoonotic pathogens that are responsible for severe diseases in both animals and humans. Salmonella enterica subsp. enterica serovar Gallinarum biovar Gallinarum (S. Gallinarum) and biovar Pullorum (S. Pullorum) are typical infectious pathogens detected in the chicken industry that have caused great economic losses. To facilitate their detection and prevent contamination, we developed a rapid multiple PCR method, which can simultaneously detect Salmonella spp. and further identify the biovars S. Pullorum/Gallinarum. This PCR detection method is based on the cigR gene, which is conserved among Salmonella spp. but has a 42-bp deletion in S. Pullorum/Gallinarum. The specificity and sensitivity of the PCR assay was evaluated with 41 different strains: 34 Salmonella strains, including 5 S. Pullorum/Gallinarum strains, and 7 non-Salmonella strains. The lower limit of detection was 8.15 pg of S. Pullorum (S06004) genomic DNA and 20 cfu in PCR, which shows a great sensitivity. In addition, this method was applied to detect or identify Salmonella from processing chicken liver and egg samples, and the results corresponded to those obtained from serotype analysis using the conventional slide agglutination test. Overall, the new cigR-based PCR assay is efficient and practical for Salmonella detection and S. Pullorum/Gallinarum identification and will greatly reduce the workload of epidemiologic investigation.

9.
Inorg Chem ; 2020 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-33103416

RESUMO

We herein report the manipulation of the crystallographic packing modes of Pt1Ag28(S-Adm)18(PPh3)4 nanoclusters by altering counterions as different polyoxometalates (POMs). Specifically, the Cl- anion of the presynthesized Pt1Ag28 nanocluster was substituted by POM anions including [Mo6O19]2-, [W6O19]2-, or [PW12O40]3-. The crystal lattices of these Pt1Ag28 nanoclusters with diverse anions showed distinct packing modes and thus manifested remarkably distinguishable crystalline-state optical properties and nitrogen adsorption-desorption performances. Overall, the combination of intercluster control in this work and intracluster control reported previously (the control over metal-ligand within the nanocluster framework) accomplished a more comprehensive manipulation over the M29(SR)18(PR'3)4 nanocluster system, which enables us to further grasp the structure-property correlations at the atomic level.

10.
Plant Biotechnol J ; 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33095976

RESUMO

Celery (Apium graveolens L. 2n = 2x = 22), a member of the Apiaceae family, is among the most important and globally grown vegetables. Here, we report a high-quality genome sequence assembly, anchored to 11 chromosomes, with total length of 3.33 Gb and N50 scaffold length of 289.78 Mb. Most (92.91%) of the genome is composed of repetitive sequences, with 62.12% of 31 326 annotated genes confined to the terminal 20% of chromosomes. Simultaneous bursts of shared long-terminal repeats (LTRs) in different Apiaceae plants suggest inter-specific exchanges. Two ancestral polyploidizations were inferred, one shared by Apiales taxa and the other confined to Apiaceae. We reconstructed 8 Apiales proto-chromosomes, inferring their evolutionary trajectories from the eudicot common ancestor to extant plants. Transcriptome sequencing in three tissues (roots, leaves and petioles), and varieties with different-coloured petioles, revealed 4 and 2 key genes in pathways regulating anthocyanin and coumarin biosynthesis, respectively. A remarkable paucity of NBS disease-resistant genes in celery (62) and other Apiales was explained by extensive loss and limited production of these genes during the last ~10 million years, raising questions about their biotic defence mechanisms and motivating research into effects of chemicals, for example coumarins, that give off distinctive odours. Celery genome sequencing and annotation facilitates further research into important gene functions and breeding, and comparative genomic analyses in Apiales.

11.
Chem Commun (Camb) ; 56(91): 14203-14206, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33111734

RESUMO

Alloying is an effective tool to comprehend the packing mechanism and adjust the properties of nanomaterials. Herein, two crystal structures of alloy nanoclusters with M13 icosahedron cores, formulated as [Pt2Ag51(S-Adm)28(PPh3)2Cl7](SbF6)2 and [Au3Ag48(S-Adm)28Cl7](SbF6)2, are determined. The preferable site(s) of alloy metals in M13 induces various packing patterns of M13. The Pt2Ag21 and Au3Ag22 kernels are observed in Pt2Ag51 and Au3Ag48, respectively. The electronic structures of these two nanoclusters are evaluated. Overall, this work presents the effect of alloying on the packing patterns of M13 and electronic structures of the metal nanoclusters.

12.
Mol Clin Oncol ; 13(6): 66, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33014365

RESUMO

Myopericytoma is a rare type of benign tumor, which commonly affects all four limbs. The occurrence of myopericytoma in the liver is extremely rare. Myopericytoma with a size of >1 cm in diameter in the liver has not been previously reported. Due to the limited number of cases, the preoperative diagnosis of liver myopericytoma based on laboratory and imaging examinations is difficult. In the present case report, a patient with multiple myopericytoma in the liver, with a maximum diameter of 4.5 cm was described, with accompanying computed tomography (CT) and positron emission tomography/CT (PET/CT) imaging profiles. The aim of the present report was to discuss the preoperative differential diagnosis between myopericytoma and other common liver neoplasms, such as intrahepatic cholangiocarcinoma or liver metastasis.

13.
Sensors (Basel) ; 20(18)2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32962133

RESUMO

Weight is an important indicator of the growth and development of dairy cows. The traditional static weighing methods require considerable human and financial resources, and the existing dynamic weighing algorithms do not consider the influence of the cow motion state on the weight curve. In this paper, a dynamic weighing algorithm for cows based on a support vector machine (SVM) and empirical wavelet transform (EWT) is proposed for classification and analysis. First, the dynamic weight curve is obtained by using a weighing device placed along a cow travel corridor. Next, the data are preprocessed through valid signal acquisition, feature extraction, and normalization, and the results are divided into three active degrees during motion for low, medium, and high grade using the SVM algorithm. Finally, a mean filtering algorithm, the EWT algorithm, and a combined periodic continuation-EWT algorithm are used to obtain the dynamic weight values. Weight data were collected for 910 cows, and the experimental results displayed a classification accuracy of 98.6928%. The three algorithms were used to calculate the dynamic weight values for comparison with real values, and the average error rates were 0.1838%, 0.6724%, and 0.9462%. This method can be widely used at farms and expand the current knowledgebase regarding the dynamic weighing of cows.

14.
ACS Appl Mater Interfaces ; 12(41): 45830-45837, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32936615

RESUMO

Herein, we report a novel strategy to enhance the antisense activity and the pharmacokinetics of therapeutic oligonucleotides. Through the DNA hybridization chain reaction, DNA hairpins modified with poly(ethylene glycol) (PEG) form a bottlebrush architecture consisting of a double-stranded DNA backbone, PEG side chains, and antisense overhangs. The assembled structure exhibits high PEG density on the surface, which suppresses unwanted interactions between the DNA and proteins (e.g., enzymatic degradation) while allowing the antisense overhangs to hybridize with the mRNA target and thereby deplete target protein expression. We show that these PEGylated bottlebrushes targeting oncogenic KRAS can achieve much higher antisense efficacy compared with unassembled hairpins with or without PEGylation and can inhibit the proliferation of lung cancer cells bearing the G12C mutant KRAS gene. Meanwhile, these structures exhibit elevated blood retention times in vivo due to the biological stealth properties of PEG and the high molecular weight of the overall assembly. Collectively, this self-assembly approach bears the characteristics of a simple, safe, yet highly translatable strategy to improve the biopharmaceutical properties of therapeutic oligonucleotides.

15.
Chem Soc Rev ; 49(17): 6443-6514, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32760953

RESUMO

Metal nanoclusters fill the gap between discrete atoms and plasmonic nanoparticles, providing unique opportunities for investigating the quantum effects and precise structure-property correlations at the atomic level. As a versatile strategy, alloying can largely improve the physicochemical performances compared to the corresponding homo-metal nanoclusters, and thus benefit the applications of such nanomaterials. In this review, we highlight the achievements of atomically precise alloy nanoclusters, and summarize the alloying principles and fundamentals, including the synthetic methods, site-preferences for different heteroatoms in the templates, and alloying-induced structure and property changes. First, based on various Au or Ag nanocluster templates, heteroatom doping modes are presented. The templates with electronic shell-closing configurations tend to maintain their structures during doping, while the others may undergo transformation and give rise to alloy nanoclusters with new structures. Second, alloy nanoclusters of specific magic sizes are reviewed. The arrangement of different atoms is related to the symmetry of the structures; that is, different atoms are symmetrically located in the nanoclusters of smaller sizes, and evolve into shell-by-shell structures at larger sizes. Then, we elaborate on the alloying effects in terms of optical, electrochemical, electroluminescent, magnetic and chiral properties, as well as the stability and reactivity via comparisons between the doped nanoclusters and their homo-metal counterparts. For example, central heteroatom-induced photoluminescence enhancement is emphasized. The applications of alloy nanoclusters in catalysis, chemical sensing, bio-labeling, and other fields are further discussed. Finally, we provide perspectives on existing issues and future efforts. Overall, this review provides a comprehensive synthetic toolbox and controllable doping modes so as to achieve more alloy nanoclusters with customized compositions, structures, and properties for applications. This review is based on publications available up to February 2020.

16.
Chin Med J (Engl) ; 133(17): 2071-2077, 2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32769486

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. Genome-wide association studies in non-Asian population revealed a link between COPD and mutations in the PTCH1 gene encoding Patched1, a receptor in the Hedgehog signaling pathway important for lung morphogenesis and pulmonary function. The aim of this study was to investigate the association between PTCH1 polymorphisms and the COPD risk in the Chinese Han population. METHODS: We performed a case-control study including 296 patients with COPD and 300 healthy individuals. Single-nucleotide polymorphisms in the PTCH1 gene were identified and genotyped based on the linkage disequilibrium analysis in all participants. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated using logistic regression analysis after adjustment for age, gender, and smoking. RESULTS: In total, 28 single-nucleotide polymorphisms were identified in patients with COPD. Among them, "A" allele of rs28491365 (OR: 1.388, 95% CI: 1.055-1.827, P = 0.018), and "G" alleles of rs10512248 (OR: 1.299, 95% CI: 1.021-1.653, P = 0.033) and rs28705285 (OR: 1.359, 95% CI: 1.024-1.803, P = 0.033; respectively) were significantly associated with an increased COPD risk. Genetic model analysis revealed that the "T/T" genotype of rs34695652 was associated with a decreased COPD risk under the recessive model (OR: 0.490, 95% CI: 0.270-0.880, P = 0.010), whereas rs28504650/rs10512248 haplotype CG was significantly associated with an increased COPD risk after adjustment for age, gender, and smoking status (OR: 6.364, 95% CI: 1.220-33.292, P = 0.028). CONCLUSIONS: The study provides a new insight into the role of PTCH1 polymorphisms in the susceptibility to COPD in the Chinese Han population.

17.
Inorg Chem ; 59(13): 8736-8743, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32501691

RESUMO

The precise manipulation of nanocluster structures remains highly desirable for disclosing the structure-property correlations at the atomic level. However, the control over a nanocluster (metal kernel + surface ligand) with a maintained template has long been a challenging pursuit, and little has been achieved for manipulation at the atomic level. Here, on the basis of the M29(SR)18(PR'3)4 cluster system, the control over the vertex phosphine ligands is accomplished. Therefore, a combination of the manipulation of vertex phosphines in this work and of internal metals and surface thiols reported previously realizes control over the M29(SR)18(PR'3)4 cluster template. The principles for regulating the photoluminescence (PL) of M29 clusters via dictation of their metal compositions, surface thiols, and vertex phosphines are exploited to rationally design the most emissive nanocluster among the M29 cluster family. Overall, this work fills the missing part necessary for the manipulation of M29(SR)18(PR'3)4 nanoclusters, providing an ideal nanomodel that enables us to grasp the structure-property correlations at the atomic level.

18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(3): 899-903, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-32552955

RESUMO

OBJECTIVE: To investigate the effect of protein kinase A (PKA) activation on aggregation funetion of platelets in vitro. METHODS: The peripheral blood of healthy adults were collected, and the washed platelets were gained from collected peripheral blood. The washed platelets were treated with PKA activator Forskolin, then the platelet aggregation was induced by using Ristocetin, Thrombin, Collagen and ADP respectively, the platelet aggregation level was detected by the platelet aggregator. RESULTS: Compared with the controls, 5 µmol/L forskolin significantly inhibited ADP and collagen-induced platelet aggregation (P<0.001), and showed mild inhibiting effect on Thrombin-induced platelet aggregation (P<0.05). 2.5-10 µmol/L forskolin significantly inhibited ADP and Collagen -induced platelet aggregation (P<0.001); but not showed significantly inhibitory effects on Ristocetin-induced platelet aggregation (P>0.05). CONCLUSION: PKA activation inhibits agonists-induced platelet aggregation.


Assuntos
Plaquetas , Agregação Plaquetária , Proteínas Quinases Dependentes de AMP Cíclico , Humanos , Inibidores da Agregação de Plaquetas , Ristocetina , Trombina
19.
J Phys Chem Lett ; 11(6): 2272-2276, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32141753

RESUMO

Doping active metal (i.e., Cu) into the kernel of noble metal nanoclusters (i.e., Au/Ag nanocluster) remains challenging in the synthesis of alloy nanoclusters. Herein, we report the synthesis and the total structure determination of a bimetallic [Ag61Cu30(SAdm)38S3]BPh4 (Ag61Cu30) nanocluster. The Ag61Cu30 nanocluster is composed of an Ag13@Cu30 kernel which is further capped by a peripheral Ag48(SAdm)38S3 shell. The icosidodecahedron Cu30 middle layer connects the innermost icosahedral Ag13 core and Ag atoms at the outermost Ag48(SR)38S3 shell, demonstrating that the Cu atoms in the Cu30 layer are in a metallic state.

20.
Chem Sci ; 11(6): 1691-1697, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32206290

RESUMO

Atomically precise engineering on the nanocluster surface remains highly desirable for the fundamental understanding of how surface structures of a nanocluster contribute to its overall properties. In this paper, the concept of "graft-onto" has been exploited to facilitate nanocluster growth on surface structures. Specifically, the Ag2(DPPM)Cl2 complex is used for re-constructing the surface structure of Pt1Ag28 (SR)18(PPh3)4 (Pt1Ag28 , SR = 1-adamantanethiolate) and producing a size-growth nanocluster - Pt1Ag31 (SR)16(DPPM)3Cl3 (Pt1Ag31 ). The grafting effect of Ag2(DPPM)Cl2 induces both direct changes on the surface structure (e.g., size growth, structural transformation, and surface rotation) and indirect changes on the kernel structure (from a fcc configuration to an icosahedral configuration). Remarkable differences have been observed by comparing optical properties between Pt1Ag28 and Pt1Ag31 . Significantly, Pt1Ag31 exhibits high photo-luminescent intensity with a quantum yield of 29.3%, which is six times that of the Pt1Ag28 . Overall, this work presents a new approach (i.e., graft-onto) for the precise dictation of nanocluster surface structures at the atomic level.

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