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1.
PhytoKeys ; 242: 1-8, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38764934

RESUMO

In this study, we describe and illustrate a new species, Primulaweiliei L.S.Yang, Z.K.Wu & G.W.Hu, from the Shennongjia Forestry District, Hubei Province in Central China. It is morphologically assigned to Primulasect.Aleuritia based on its dwarf and hairless habit, long petiole, fruits longer than calyx and covered by farina on the scape. This new species is similar to P.gemmifera and P.munroisubsp.yargongensis in the same section, but it can be distinguished by its smaller calyxes, homostylous flowers, corolla tube throat without annular appendage and only 1-2 flowers in each inflorescence. Based on the assessment conducted according to the IUCN Red List criteria, we propose that P.weiliei be classified as a Critically Endangered (CR) species.

2.
Angew Chem Int Ed Engl ; : e202407518, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752452

RESUMO

Gold nanoclusters exhibiting concomitant photothermy (PT) and photoluminescence (PL) under near-infrared (NIR) light irradiation are rarely reported, and some fundamental issues remain unresolved for such materials. Herein, we concurrently synthesized two novel rod-shaped Au nanoclusters, Au52(PET)32 and Au66(PET)38 (PET = 2-phenylethanethiol), and precisely revealed that their kernels were 4 × 4 × 6 and 5 × 4 × 6 face-centered cubic (fcc) structures, respectively, based on the numbers of Au layers in the [100], [010], and [001] directions. Following the structural growth mode from Au52(PET)32 to Au66(PET)38, we predicted six more novel nanoclusters. The concurrent synthesis provides rational comparison of the two nanoclusters on the stability, absorption, emission and photothermy, and reveals the aspect ratio-related properties. An interesting finding is that the two nanoclusters exhibit concomitant PT and PL under 785 nm light irradiation, and the PT and PL are in balance, which was explained by the qualitative evaluation of the radiative and non-radiative rates. The ligand effects on PT and PL were also investigated.

3.
Angew Chem Int Ed Engl ; : e202402565, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38588114

RESUMO

Atomically precise ~1-nm Pt nanoparticles (nanoclusters, NCs) with ambient stability are important in fundamental research and exhibit diverse practical applications (catalysis, biomedicine, etc.). However, synthesizing such materials is challenging. Herein, by employing the mixture ligand protecting strategy, we successfully synthesized the largest organic-ligand-protected (~1-nm) Pt23 NCs precisely characterized with mass spectrometry and single-crystal X-ray diffraction analyses. Interestingly, natural population analysis and Bader charge calculation indicate an alternate, varying charge -layer distribution in the sandwich-like Pt23 NC kernel. Pt23 NCs can catalyze the oxygen reduction reaction under acidic conditions without requiring calcination and other treatments, and the resulting specific and mass activities without further treatment are sevenfold and eightfold higher than those observed for commercial Pt/C catalysts, respectively. Density functional theory and d-band center calculations interpret the high activity. Furthermore, Pt23 NCs exhibit a photothermal conversion efficiency of 68.4 % under 532-nm laser irradiation and can be used at least for six cycles, thus demonstrating great potential for practical applications.

4.
Genes Genet Syst ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38556272

RESUMO

Primula secundiflora is an insect-pollinated, perennial herb belonging to section Proliferae (Primulaceae) and exhibits considerable variation in mating system with predominantly outcrossing populations comprising long-styled and short-styled floral morphs and selfing populations comprising only homostyles. To facilitate future investigations of the population genetics and mating patterns of this species, we developed 25 microsatellite markers from P. secundiflora using next-generation sequencing and measured polymorphism and genetic diversity in a sample of 30 individuals from three natural populations. The markers displayed relatively high polymorphism, with the number of observed alleles per locus ranging from three to 16 (mean = 8.36). The observed and expected heterozygosities ranged from 0.100 to 1.000 and 0.145 to 0.843, respectively. Twenty-one of the loci were also successfully amplified in P. denticulata. These microsatellite markers could provide powerful tools for investigating patterns of population genetic diversity and the evolutionary relationships between distyly and homostyly in this species.

5.
J Am Chem Soc ; 146(13): 9026-9035, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38441064

RESUMO

The introduction of single or multiple heterometal atoms into metal nanoparticles is a well-known strategy for altering their structures (compositions) and properties. However, surface single nonmetal atom doping is challenging and rarely reported. For the first time, we have developed synthetic methods, realizing "surgery"-like, successive surface single nonmetal atom doping, replacement, and addition for ultrasmall metal nanoparticles (metal nanoclusters, NCs), and successfully synthesized and characterized three novel bcc metal NCs Au38I(S-Adm)19, Au38S(S-Adm)20, and Au38IS(S-Adm)19 (S-Adm: 1-adamantanethiolate). The influences of single nonmetal atom replacement and addition on the NC structure and optical properties (including absorption and photoluminescence) were carefully investigated, providing insights into the structure (composition)-property correlation. Furthermore, a bottom-up method was employed to construct a metal-organic framework (MOF) on the NC surface, which did not essentially alter the metal NC structure but led to the partial release of surface ligands and stimulated metal NC activity for catalyzing p-nitrophenol reduction. Furthermore, surface MOF construction enhanced NC stability and water solubility, providing another dimension for tunning NC catalytic activity by modifying MOF functional groups.

6.
Nucleic Acids Res ; 52(5): 2212-2230, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38364871

RESUMO

Nonreference sequences (NRSs) are DNA sequences present in global populations but absent in the current human reference genome. However, the extent and functional significance of NRSs in the human genomes and populations remains unclear. Here, we de novo assembled 539 genomes from five genetically divergent human populations using long-read sequencing technology, resulting in the identification of 5.1 million NRSs. These were merged into 45284 unique NRSs, with 29.7% being novel discoveries. Among these NRSs, 38.7% were common across the five populations, and 35.6% were population specific. The use of a graph-based pangenome approach allowed for the detection of 565 transcript expression quantitative trait loci on NRSs, with 426 of these being novel findings. Moreover, 26 NRS candidates displayed evidence of adaptive selection within human populations. Genes situated in close proximity to or intersecting with these candidates may be associated with metabolism and type 2 diabetes. Genome-wide association studies revealed 14 NRSs to be significantly associated with eight phenotypes. Additionally, 154 NRSs were found to be in strong linkage disequilibrium with 258 phenotype-associated SNPs in the GWAS catalogue. Our work expands the understanding of human NRSs and provides novel insights into their functions, facilitating evolutionary and biomedical researches.


Assuntos
Genoma Humano , Estudo de Associação Genômica Ampla , Grupos Populacionais , Humanos , Diabetes Mellitus Tipo 2/genética , Desequilíbrio de Ligação , Fenótipo , Polimorfismo de Nucleotídeo Único , Genética Populacional , Grupos Populacionais/genética
7.
Front Oncol ; 14: 1337707, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38414741

RESUMO

Background: The identification of effective tumor markers is of paramount importance for the early diagnosis, treatment, and prognosis of esophageal squamous cell carcinoma (ESCC). The present study endeavors to identify efficacious serological markers that can differentiate patients with early-stage ESCC from those with benign esophageal lesions and healthy controls (HC). Cystatin-SN (CST1), an active cysteine protease inhibitor belonging to the Cystatin (CST) superfamily, is implicated in the pathogenesis of inflammation and tumorigenesis. The objective of this investigation is to assess the diagnostic, therapeutic, and prognostic potential of serum CST1 in ESCC. Methods: In our prior RNA sequencing and screening endeavors, we have identified ten genes that are up-regulated in relation to esophageal cancer. Subsequently, we have verified the gene CST1 from the transcriptome data of the The Cancer Genome Atlas Program (TCGA) and Gene Expression Profiling Interactive Analysis (GEPIA) database. Following this, we conducted an enzyme-linked immunosorbent assay (ELISA) to ascertain the expression levels of CST1 in serum samples from clinical cohorts. Results: The study revealed a significant elevation in serum CST1 levels among patients with early-stage esophageal squamous cell carcinoma (ESCC) (7.41 ± 4.32 ng/ml) compared to those with esophageal benign lesions (4.67 ± 2.43 ng/ml) (p < 0.0001) and healthy controls (4.87 ± 2.77 ng/ml) (p < 0.0001). The diagnostic sensitivity of CST1 for ESCC was 75.68% (specificity 70.83%, AUC 0.775). Combination of CST1 and SCC-Ag exhibited the AUC up to 0.819. Additionally, serum CST1 levels exhibited a significant decrease at 1-2 weeks post-surgery (4.49 ± 3.31 ng/ml) compared to pre-surgery levels (7.68 ± 3.71 ng/ml) (p<0.0001). Survival analysis demonstrated a strong association between high (844/415-1543 d) or low (1490/645-1710 d) serum CST1 levels at diagnosis and overall survival time (p < 0.001). Furthermore, multivariate regression analysis confirmed CST1 (p=0.024, HR=2.023, 95%CI 1.099-3.725) as an independent prognostic factor. Conclusion: Serum CST1 has the potential to function as a diagnostic indicator for distinguishing early-stage esophageal squamous cell carcinoma (ESCC) from individuals with benign esophageal lesions and healthy individuals. Additionally, it could serve as a prognostic predictor and therapeutic efficacy indicator for patients with ESCC.

8.
Nano Lett ; 24(7): 2226-2233, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38251911

RESUMO

Atomically precise doping of metal nanoclusters provides excellent opportunities not only for subtly tailoring their properties but also for in-depth understanding of composition (structure)-property correlation of metal nanoclusters and has attracted increasing interest partly due to its significance for fundamental research and practical applications. Although single and multiple metal atom doping of metal nanoclusters (NCs) has been achieved, sequential single-to-multiple metal atom doping is still a big challenge and has not yet been reported. Herein, by introducing a second ligand, a novel multistep synthesis method was developed, controlled sequential single-to-multiple metal atom doping was successfully achieved for the first time, and three doped NCs Au25Cd1(p-MBT)17(PPh3)2, Au18Cd2(p-MBT)14(PPh3)2, and [Au19Cd3(p-MBT)18]- (p-MBTH: para-methylbenzenethiol) were obtained, including two novel NCs that were precisely characterized via mass spectrometry, single-crystal X-ray crystallography, and so forth. Furthermore, sequential doping-induced evolutions in the atomic and crystallographic structures and optical and catalytic properties of NCs were revealed.

9.
New Phytol ; 242(1): 302-316, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38214455

RESUMO

Evolutionary transitions from outcrossing to selfing in flowering plants have convergent morphological and genomic signatures and can involve parallel evolution within related lineages. Adaptive evolution of morphological traits is often assumed to evolve faster than nonadaptive features of the genomic selfing syndrome. We investigated phenotypic and genomic changes associated with transitions from distyly to homostyly in the Primula oreodoxa complex. We determined whether the transition to selfing occurred more than once and investigated stages in the evolution of morphological and genomic selfing syndromes using 22 floral traits and both nuclear and plastid genomic data from 25 populations. Two independent transitions were detected representing an earlier and a more recently derived selfing lineage. The older lineage exhibited classic features of the morphological and genomic selfing syndrome. Although features of both selfing syndromes were less developed in the younger selfing lineage, they exhibited parallel development with the older selfing lineage. This finding contrasts with the prediction that some genomic changes should lag behind adaptive changes to morphological traits. Our findings highlight the value of comparative studies on the timing and extent of transitions from outcrossing to selfing between related lineages for investigating the tempo of morphological and molecular evolution.


Assuntos
Flores , Primula , Flores/genética , Flores/anatomia & histologia , Genômica , Primula/genética , Evolução Biológica , Reprodução/genética , Polinização , Autofertilização/genética
10.
Angew Chem Int Ed Engl ; 63(3): e202313491, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37990769

RESUMO

Constructing ambient-stable, single-atom-layered metal-based materials with atomic precision and understanding their underlying stability mechanisms are challenging. Here, stable single-atom-layered nanoclusters of Pd were synthesized and precisely characterized through electrospray ionization mass spectrometry and single-crystal X-ray crystallography. A pseudo-pentalene-like Pd8 unit was found in the nanocluster, interacting with two syn PPh units through nonmetal-to-metal -ring coordination. The unexpected coordination, which is distinctly different from the typical organoring-to-metal coordination in half-sandwich-type organometallic compounds, contributes to the ambient stability of the as-obtained single-atom-layered nanocluster as revealed through theoretical and experimental analyses. Furthermore, quantum chemical calculations revealed dominant electron transition along the horizontal x-direction of the Pd8 plane, indicating high photothermal conversion efficiency (PCE) of the nanocluster, which was verified by the experimental PCE of 73.3 %. Therefore, this study unveils the birth of a novel type of compound and the finding of the unusual nonmetal-to-metal -ring coordination and has important implications for future syntheses, structures, properties, and structure-property correlations of single-atom-layered metal-based materials.

11.
Small ; 20(9): e2305556, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37849043

RESUMO

Metal nanoclusters with precisely modulated structures at the nanoscale give us the opportunity to synthesize and investigate 1D nanomaterials at the atomic level. Herein, it realizes selective 1D growth of building block nanocluster "Au13 Cd2 " into three structurally different nanoclusters: "hand-in-hand" (Au13 Cd2 )2 O, "head-to-head" Au25 , and "shoulder-to-shoulder" Au33 . Detailed studies further reveals the growth mechanism and the growth-related tunable properties. This work provides new hints for the predictable structural transformation of nanoclusters and atomically precise construction of 1D nanomaterials.

12.
Clin Lab ; 69(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37948495

RESUMO

BACKGROUND: This study was designed to compare the body fluid module of Sysmex XN9000 (XN-BF) with optical microscopy (OM) for cerebrospinal fluid (CSF) analysis after two-step cell slide centrifuge (TSCSC), defining the best procedure for CSF optical microscopy analysis. METHODS: Items of RBC, WBC enumeration and differentiation were observed. The cell count and morphologic evaluation of the cellular composition by OM was carried out both with and without two-step cell slide centrifuge (TSCSC) and were compared the data with XN-BF. RESULTS: There were 69.98 ± 4.94 RBC and 36.98 ± 3.39 WBC in one OSCSC microscopic field whereas there were 96.35 ± 5.41 RBC and 66.15 ± 4.85 WBC in one TSCSC microscopic field in the same sample (*200). There was a statistical difference between those two methods (p = 0.000). Excellent correlation was found between total cell count with both OM and XN-BF. The R2 value for RBC and WBC counts were 0.99 and 0.96, respectively. For WBC differential, the R2 values were 0.98 for PMN and 0.70 for MN. Correlation of MN was poorer than PMN. As far as the tumor cell, phagocyte, and plasma cell with high fluorescence were concerned, OM were not consistent with XN-BF. CONCLUSIONS: The TSCSC procedure contributes to the separation of cells and other ingredients. XN-BF displays excellent performance at RBC and WBC cell count except for mononuclear cells, tumor cells, phagocytes, and leukemia cells. which makes it just a practical alternative to total cell (WBC, RBC) count for CSF samples. Detailed morphologic workup of CSF samples is mandated in all cases with meningoencephalitis, elevated cell count, sub-arachnoid hemorrhage and meningeal carcinomatosis, the TSCSC procedure is recommended.


Assuntos
Líquidos Corporais , Microscopia , Humanos , Contagem de Leucócitos , Leucócitos , Diferenciação Celular , Líquido Cefalorraquidiano , Reprodutibilidade dos Testes
13.
J Am Chem Soc ; 145(44): 24012-24020, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37903430

RESUMO

Understanding charge transport among metal particles with sizes of approximately 1 nm poses a great challenge due to the ultrasmall nanosize, yet it holds great significance in the development of innovative materials as substitutes for traditional semiconductors, which are insulative and unstable in less than ∼10 nm thickness. Herein, atomically precise gold nanoclusters with well-defined compositions and structures were investigated to establish a mathematical relation between conductivity and interparticle distance. This was accomplished using high-pressure in situ resistance characterizations, synchrotron X-ray diffraction (XRD), and the Murnaghan equation of state. Based on this precise correlation, it was predicted that the conductivity of Au25(SNap)18 (SNap: 1-naphthalenethiolate) solid is comparable to that of bulk silver when the interparticle distance is reduced to approximately 3.6 Å. Furthermore, the study revealed the coexisting, competing tunneling, and incoherent hopping charge transport mechanisms, which differed from those previously reported. The introduction of conjugation-structured ligands, tuning of the structures of metal nanoclusters, and use of high-pressure techniques contributed to enhanced conductivity, and thus, the charge carrier types were determined using Hall measurements. Overall, this study provides valuable insight into the charge transport in gold nanocluster solids and represents an important advancement in metal nanocluster semiconductor research.

14.
Plant Biotechnol J ; 21(12): 2473-2489, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37558431

RESUMO

Asparagus bean (Vigna unguiculata ssp. sesquipedialis), a subspecies of V. unguiculata, is a vital legume crop widely cultivated in Asia for its tender pods consumed as vegetables. However, the existing asparagus bean assemblies still contain numerous gaps and unanchored sequences, which presents challenges to functional genomics research. Here, we present an improved reference genome sequence of an elite asparagus bean variety, Fengchan 6, achieved through the integration of nanopore ultra-long reads, PacBio high-fidelity reads, and Hi-C technology. The improved assembly is 521.3 Mb in length and demonstrates several enhancements, including a higher N50 length (46.4 Mb), an anchor ratio of 99.8%, and the presence of only one gap. Furthermore, we successfully assembled 14 telomeres and all 11 centromeres, including four telomere-to-telomere chromosomes. Remarkably, the centromeric regions cover a total length of 38.1 Mb, providing valuable insights into the complex architecture of centromeres. Among the 30 594 predicted protein-coding genes, we identified 2356 genes that are tandemly duplicated in segmental duplication regions. These findings have implications for defence responses and may contribute to evolutionary processes. By utilizing the reference genome, we were able to effectively identify the presence of the gene VuMYB114, which regulates the accumulation of anthocyanins, thereby controlling the purple coloration of the pods. This discovery holds significant implications for understanding the underlying mechanisms of color determination and the breeding process. Overall, the highly improved reference genome serves as crucial resource and lays a solid foundation for asparagus bean genomic studies and genetic improvement efforts.


Assuntos
Antocianinas , Fabaceae , Antocianinas/genética , Genoma de Planta/genética , Melhoramento Vegetal , Fabaceae/genética , Genômica
16.
Angew Chem Int Ed Engl ; 62(39): e202308441, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37428452

RESUMO

Lattice tuning at the ≈1 nm scale is fascinating and challenging; for instance, lattice compression at such a minuscule scale has not been observed. The lattice compression might also bring about some unusual properties, which waits to be verified. Through ligand induction, we herein achieve the lattice compression in a ≈1 nm gold nanocluster for the first time, as detected by the single-crystal X-ray crystallography. In a freshly synthesized Au52 (CHT)28 (CHT=S-c-C6 H11 ) nanocluster, the lattice distance of the (110) facet is found to be compressed from 4.51 to 3.58 Šat the near end. However, the lattice distances of the (111) and (100) facets show no change in different positions. The lattice-compressed nanocluster exhibits superior electrocatalytic activity for the CO2 reduction reaction (CO2 RR) compared to that exhibited by the same-sized Au52 (TBBT)32 (TBBT=4-tert-butyl-benzenethiolate) nanocluster and larger Au nanocrystals without lattice variation, indicating that lattice tuning is an efficient method for tailoring the properties of metal nanoclusters. Further theoretical calculations explain the high CO2 RR performance of the lattice-compressed Au52 (CHT)28 and provide a correlation between its structure and catalytic activity.

17.
PhytoKeys ; 227: 25-33, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37287937

RESUMO

Primulajiaozishanensis Z.K.Wu, W.H.Yang & Yuan Wu, a new species of Primulaceae is described and illustrated from Jiaozi Snow Mountain of Dongchuan District, Yunnan, China. Morphological evidence supports P.jiaozishanensis as a member of P.sect.Petiolaressubsect.Davidii, which is characterized by firmly papery or leathery leaves, with veins impressed adaxially, often prominently raised and alveolate abaxially. The new species is characterized by having long and stout rhizomes, smaller leaves with short petioles, short or almost obsolete scape, and larger flowers. The distribution, phenology and conservation status of the new species are also provided.

18.
PhytoKeys ; 227: 35-42, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37287940

RESUMO

The rare Primulabrachystoma W.W.Sm. is an endemic species confined to Gaoligong mountain of Chinese-Burma frontier, which has been rediscovered from the same region after nearly 100 years. In total, 11 specimens from Gaoligong Mountain have been found in the herbaria worldwide, since its first collection in 1920 by Farrer, Reginald John. Previously, this species was described as homostylous but our finding shows the species also exhibited heterostyly. A complete description of the species, the distribution, morphological comparison and identification key from closely related species are provided here. An assessment of its conservation status suggests that the species is 'Endangered' (EN).

19.
Front Chem ; 11: 1156891, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37304683

RESUMO

We have proposed, for the first time, an OpenCL implementation for the all-electron density-functional perturbation theory (DFPT) calculations in FHI-aims, which can effectively compute all its time-consuming simulation stages, i.e., the real-space integration of the response density, the Poisson solver for the calculation of the electrostatic potential, and the response Hamiltonian matrix, by utilizing various heterogeneous accelerators. Furthermore, to fully exploit the massively parallel computing capabilities, we have performed a series of general-purpose graphics processing unit (GPGPU)-targeted optimizations that significantly improved the execution efficiency by reducing register requirements, branch divergence, and memory transactions. Evaluations on the Sugon supercomputer have shown that notable speedups can be achieved across various materials.

20.
PhytoKeys ; 221: 85-93, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37250357

RESUMO

Primulapingbaensis Na Zhang, X.Q.Jiang & Z.K.Wu, a new species of Primulaceae from Gaofeng Mountain of Pingba county, Guizhou, China, is described and illustrated. Morphological evidence supports P.pingbaensis as a member of P.sect.Petiolares on account of scape elongating, pedicels conspicuously thickening in fruit, and its capsule cracking irregularly round the top and crumbling away. Amongst the members of subsect. Davidii, the new species is characterized by having a uniquely smooth leaf blade due to inconspicuously raised veinlets and homostylous flowers with the style usually extending beyond the anthers. The distribution, phenology and conservation status of the new species are also provided.

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