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1.
Nat Commun ; 15(1): 5139, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886388

RESUMO

Although it is well documented that mountains tend to exhibit high biodiversity, how geological processes affect the assemblage of montane floras is a matter of ongoing research. Here, we explore landform-specific differences among montane floras based on a dataset comprising 17,576 angiosperm species representing 140 Chinese mountain floras, which we define as the collection of all angiosperm species growing on a specific mountain. Our results show that igneous bedrock (granitic and karst-granitic landforms) is correlated with higher species richness and phylogenetic overdispersion, while the opposite is true for sedimentary bedrock (karst, Danxia, and desert landforms), which is correlated with phylogenetic clustering. Furthermore, we show that landform type was the primary determinant of the assembly of evolutionarily older species within floras, while climate was a greater determinant for younger species. Our study indicates that landform type not only affects montane species richness, but also contributes to the composition of montane floras. To explain the assembly and differentiation of mountain floras, we propose the 'floristic geo-lithology hypothesis', which highlights the role of bedrock and landform processes in montane floristic assembly and provides insights for future research on speciation, migration, and biodiversity in montane regions.


Assuntos
Biodiversidade , Magnoliopsida , Filogenia , China , Magnoliopsida/crescimento & desenvolvimento , Altitude , Fenômenos Geológicos , Ecossistema
2.
Clin Neurol Neurosurg ; 231: 107797, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37263069

RESUMO

OBJECTIVE: This study examined the effect of repetitive transcranial magnetic stimulation (rTMS) combined with transcranial direct current stimulation (tDCS) as a bimodal neuromodulatory approach for post-stroke dysmnesia. METHODS: Thirty-four patients with post-stroke dysmnesia were randomly allocated into a sham group treated with neither rTMS nor tDCS, a group treated with rTMS, and a group treated with a combination of rTMS and tDCS. All three groups received cognitive rehabilitation training for 4 weeks. The memory function of each group before and after the intervention was assessed using the Montreal Cognitive Assessment (MoCA) and Rivermead Behavioral Memory Test (RBMT) scales, as well as in terms of the Mismatch Negativity(MMN)and P300 of event-related potentials. RESULTS: The sham, rTMS, and rTMS-tDCS groups all showed improvement in the total MoCA score after the intervention. Delayed recall, a MoCA item, scored better in the rTMS-tDCS group than in the rTMS and sham groups. Delayed processing, an RBMT item, scored better in the rTMS-tDCS combination group than in the rTMS and sham groups. MMN and P300 latency was significantly shorter in the rTMS-tDCS combination group. CONCLUSION: rTMS-tDCS bimodal stimulation was more effective than cognitive rehabilitation or rTMS alone in treating patients with post-stroke dysmnesia, offering new possibilities for enhancing cognitive function and treating post-stroke dysmnesia.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Estimulação Transcraniana por Corrente Contínua , Humanos , Estimulação Magnética Transcraniana , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Memória , Amnésia
3.
Plant Divers ; 44(3): 279-289, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35769588

RESUMO

The diverse members of the genus Daphne are prized for their fragrant flowers. Despite being promising ornamental plants in many countries, genetic information of Daphne is scarce. In this study, the plastomes of four species and one variety of Daphne were sequenced and analyzed. The plastomes were typical and contained a pair of inverted repeat (IR) regions that separated the large single-copy (LSC) region from the small single-copy (SSC) region. With a length ranging from 132,869 bp (D. genkwa) to 174,773 bp (D. championii), 106 to 141 genes were predicted. Comparative plastome analysis of the newly sequenced plastomes with four publicly available Daphne plastomes identified an expansion of the IRs, sequence variations, and mutational hotspots. Phylogenetic analyses indicated that the genus Daphne in its current circumscription is polyphyletic. Daphne genkwa was nested within the genus Wikstroemia, while D. championii was well resolved as sister to Edgeworthia. These findings concurred with results from our study that used nuclear ribosomal internal transcribed spacer sequence data. The conflicts on the molecular placement of D. championii and D. genkwa and the present taxonomic classification in Daphne suggest that a new intergeneric classification system of Daphneae warrants consideration.

4.
Chin J Nat Med ; 18(11): 855-859, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33308608

RESUMO

Four new compounds, asperisocoumarin G (1), asperisocoumarin H (2), (±)-asperisocoumarin I [(±)-3], along with the known pergillin (4) and penicisochroman L (5) were isolated from a mangrove endophytic fungus Aspergillus sp. 085242 by further chemical investigation. The structures of the new compounds, including their absolute configurations, were established by analysis of HR-ESI-MS and NMR spectroscopic data, and ECD calculation. Asperisocoumarins G-I (1-3) were new isocoumarins belonging to the class of furo[3, 2-h]isocoumarins which are rarely found in natural sources. All of the isolated compounds were evaluated for their α-glucosidase inhibitory effects, and compounds 1 and 4 showed moderate α-glucosidase inhibitory activity, respectively. In an antimicrobial test, the racemate of 3 showed antibacterial activity against Salmonella.


Assuntos
Antibacterianos/farmacologia , Aspergillus/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Isocumarinas/química , Isocumarinas/isolamento & purificação , Isocumarinas/farmacologia , Estrutura Molecular
5.
J Comput Chem ; 35(6): 415-26, 2014 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-24497309

RESUMO

In this article, a polarizable dipole-dipole interaction model is established to estimate the equilibrium hydrogen bond distances and the interaction energies for hydrogen-bonded complexes containing peptide amides and nucleic acid bases. We regard the chemical bonds N-H, C=O, and C-H as bond dipoles. The magnitude of the bond dipole moment varies according to its environment. We apply this polarizable dipole-dipole interaction model to a series of hydrogen-bonded complexes containing the N-H···O=C and C-H···O=C hydrogen bonds, such as simple amide-amide dimers, base-base dimers, peptide-base dimers, and ß-sheet models. We find that a simple two-term function, only containing the permanent dipole-dipole interactions and the van der Waals interactions, can produce the equilibrium hydrogen bond distances compared favorably with those produced by the MP2/6-31G(d) method, whereas the high-quality counterpoise-corrected (CP-corrected) MP2/aug-cc-pVTZ interaction energies for the hydrogen-bonded complexes can be well-reproduced by a four-term function which involves the permanent dipole-dipole interactions, the van der Waals interactions, the polarization contributions, and a corrected term. Based on the calculation results obtained from this polarizable dipole-dipole interaction model, the natures of the hydrogen bonding interactions in these hydrogen-bonded complexes are further discussed.


Assuntos
Ligação de Hidrogênio , Modelos Químicos , Ácidos Nucleicos/química , Peptídeos/química , Modelos Moleculares , Termodinâmica
6.
Dalton Trans ; 40(20): 5584-90, 2011 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-21503365

RESUMO

Eleven new lanthanide oxalatophosphonate hybrids with a 2D layered structures, namely, [Ln(H(3)L)(C(2)O(4))]·2H(2)O (Ln = La-Dy, Er and Y, H(4)L = C(6)H(5)CH(2)N(CH(2)PO(3)H(2))(2)), have been synthesized under hydrothermal conditions and structurally characterized by X-ray single-crystal diffraction, X-ray powder diffraction, infrared spectroscopy, elemental analysis and thermogravimetric analysis. Compounds 1-11 are isomorphous and they exhibit a 2D framework structure. Two {LnO(8)} polyhedra and four {CPO(3)} tetrahedra are interconnected into a unit via corner-sharing, and the so-built units are bridged by the oxalate anions into a layer. The result of connections in this manner is the formation of a 24-atom window. The thermal stabilities and guest desorption-sorption properties of compounds 1-11 have been investigated. The luminescent properties of compounds 5, 6, 8 and 9 have also been studied.

7.
Chem Commun (Camb) ; (19): 2721-3, 2009 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-19532933

RESUMO

A new polyoxometalate-templated Mo/V-oxide-based organic-inorganic hybrid framework with a honeycomb-like structure has been hydrothermally synthesized and its electrocatalytic property was investigated.

8.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): o534, 2008 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-21201553

RESUMO

The title compound, C(13)H(12)O(2)S(2), belonging to the group of dioxoketene cyclic S,S-acetals, was prepared from the corresponding dione in high yield. In the structure, the C=O and C=C bonds are not coplanar, with O=C-C=C torsion angles of -36.8 (4) and -21.0 (4)°. The dithian ring has a twisted conformation.

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