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1.
Chemistry ; : e202403447, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39401948

RESUMO

The development of heterogeneous palladium catalysts has shown continuous vitality in the field of catalysis and materials. In this work, we report one concise free radical polymerization approach to accomplish the aromatic palladium trimer functionalized polymers PSSy-[Pd3]+ (2) and its derived palladium nanoparticles (3). Full characterizations could confirm the successful combination of cationic [Pd3]+ or nanoparticles with poly(p-sulfonated styrene) skeleton. Compared to their monomeric tri-palladium precursor (1) and common Pd(dba)2, Pd(PPh3)4, Pd(OAc)2, heterogeneous PSSy-[Pd3]+ (2) shows much superior catalytic activities (0.15 mol%, TOF = 1333.3 h-1) in the SMCC reaction. The identically ligated PdNPs (3) are formed in-suit in the presence of NaBH4 and accomplish quantitative reduction of 4-nitrophenol in just 320 s (0.50 mol%, TOF = 2250 h-1). Moreover, these heterogeneous catalysts are reused for 5-6 times without significant loss of catalytic activity. Their superior catalytic ability is probably attributed to the synergistic effect of polymer entanglement and the tri-palladium fragment. This work enlightens that the immobilization of palladium clusters or nanoparticles by polymerization could offer multiple advantages in stability, efficiency and recyclability for their involved catalyses and show far-reaching future implications.

2.
Ecotoxicol Environ Saf ; 223: 112554, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34332247

RESUMO

Arsenic is one of the most common environmental pollutants. Neurotoxicity induced by arsenic has become a major public health concern. However, the effects of arsenic-induced neurotoxicity in the brain and the underlying molecular mechanisms are not well understood. N-acetyl-cysteine (NAC) is a thiol-based antioxidant that can antagonize heavy metal-induced neurotoxicity by scavenging reactive oxygen species (ROS). Here, we used the mouse oligodendrocyte precursor cell (OPC) line Oli-neu to explore the neurotoxic effects of arsenic and the protective effects of NAC. We found that arsenic exposure decreased cell viability, increased oxidative stress, caused mitochondrial dysfunction, and led to apoptosis of Oli-neu cells. Furthermore, we revealed that NAC treatment reversed these neurotoxic effects of arsenic. TMEM179, a key membrane protein, was found highly expressed in OPCs and to be an important factor in maintaining mitochondrial functions. We found that TMEM179 played a critical role in mediating the neurotoxic effects of arsenic and the protective role of NAC. PKCß is a downstream factor through which TMEM179 regulates the expression of apoptosis-related proteins. This study improves our understanding of the neurotoxic effects and mechanisms of arsenic exposure and the protective effects of NAC. It also identifies a potential molecular target, TMEM179, for the treatment of arsenic-induced neurotoxicity.


Assuntos
Acetilcisteína , Arsênio , Acetilcisteína/metabolismo , Acetilcisteína/farmacologia , Animais , Apoptose , Arsênio/metabolismo , Arsênio/toxicidade , Camundongos , Mitocôndrias/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
3.
Dermatol Ther ; 33(2): e13223, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31917488

RESUMO

Fox-Fordyce disease (FFD) is a rare pruritic dermatosis whose etiology has not been fully explored. It is mostly seen in women and presents as pruritic follicular papules at the apocrine (gland-bearing) regions, including the axilla, groins, perineum, and areola mammae, as well as the umbilicus. Treatment for FFD is extremely challenging in that there is no curative treatment for it. We report the case of a 26-year-old woman who was refractory to many treatments but who responded to calcipotriol betamethasone with rapid remission of her symptoms.


Assuntos
Doença de Fox-Fordyce , Remoção de Cabelo , Adulto , Axila , Betametasona/uso terapêutico , Calcitriol/análogos & derivados , Feminino , Doença de Fox-Fordyce/diagnóstico , Doença de Fox-Fordyce/tratamento farmacológico , Humanos
4.
Macromol Rapid Commun ; 40(21): e1900406, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31557369

RESUMO

Thermal stability of polymer structure is a key to achieve stable energy density at elevated temperature for ferroelectric-polymer-based capacitors. Here, a poly (vinylidene fluoride) / polymethyl methacrylate (PMMA) blend with a stabilized spherulite structure displaying steady energy density around 7.8-9.8 J cm-3 across the temperature range up to 70 °C is reported, which outperforms most neat ferroelectric polymers at elevated temperature. The microstructure of the blend observed by atomic force microscopy exhibits an alternating lamellar structure (crystalline/mixed amorphous layers) within spherulites, which might be rationalized by PMMA being gradually expelled from the spherulite and finally staying between PVDF lamellae during crystallization. The structure with rigid amorphous layers can induce a spatial confinement effect of chain motion and structural change under thermal stress, which is evidenced by temperature-insensitive long period in small-angle X-ray scattering measurements. The enhanced thermal stability of energy storage can be attributed to the constraint on free volume and carrier transportation caused by the spatial confinement. Our findings provide a strategy to attain temperature-stable high-energy-density ferroelectric polymers for energy storage capacitors.


Assuntos
Polimetil Metacrilato/química , Polivinil/química , Temperatura , Espalhamento a Baixo Ângulo , Difração de Raios X
5.
Zookeys ; 1204: 191-198, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38882564

RESUMO

Melanasterasinica He & Burckhardt, sp. nov., a new psylloid species developing on Grewia sp., is described from Hainan, China. It is the first Melanastera species reported from Asia and China, and the second species from the Old World. While New World species of Melanastera are mostly associated with the plant families Melastomataceae and Annonaceae, the two Old World species develop on the malvaceous Grewia, a host otherwise used in psylloids by two Haplaphalara species. The new species is described, diagnosed and illustrated, and its host plant and biogeographic ranges are discussed.

6.
Sci Data ; 11(1): 1169, 2024 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-39461974

RESUMO

Cyamophila willieti (Hemiptera: Psyllidae) is a significant pest that adversely affects the growth of Styphnolobium japonicum and its variant, Styphnolobium japonicum f. pendula. Despite its impact, research on this species remains limited. In this study, we successfully assembled a chromosome-level genome for Cyamophila willieti using a comprehensive approach that integrated Illumina sequencing, PacBio sequencing, and Hi-C technology. The genome size was determined to be 361.61 Mb, with a scaffold N50 length of 28.90 Mb. Additionally, the genome was mapped to 13 chromosomes (N = 12 A + X), and a total of 15,841 genes were predicted, with 90.38% of them functionally annotated. In summary, the high-quality genome of Cyamophila willieti provides valuable data to support further research, including pest management strategies.


Assuntos
Genoma de Inseto , Hemípteros , Animais , Hemípteros/genética , Cromossomos de Insetos , Tamanho do Genoma
7.
Gigascience ; 13(1)2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38372702

RESUMO

BACKGROUND: Lice (Psocodea: Phthiraptera) are one important group of parasites that infects birds and mammals. It is believed that the ancestor of parasitic lice originated on the ancient avian host, and ancient mammals acquired these parasites via host-switching from birds. Here we present the first chromosome-level genome of Menopon gallinae in Amblycera (earliest diverging lineage of parasitic lice). We explore the transition of louse host-switching from birds to mammals at the genomic level by identifying numerous idiosyncratic genomic variations. RESULTS: The assembled genome is 155 Mb in length, with a contig N50 of 27.42 Mb. Hi-C scaffolding assigned 97% of the bases to 5 chromosomes. The genome of M. gallinae retains a basal insect repertoire of 11,950 protein-coding genes. By comparing the genomes of lice to those of multiple representative insects in other orders, we discovered that gene families of digestion, detoxification, and immunity-related are generally conserved between bird lice and mammal lice, while mammal lice have undergone a significant reduction in genes related to chemosensory systems and temperature. This suggests that mammal lice have lost some of these genes through the adaption to environment and temperatures after host-switching. Furthermore, 7 genes related to hematophagy were positively selected in mammal lice, suggesting their involvement in the hematophagous behavior. CONCLUSIONS: Our high-quality genome of M. gallinae provides a valuable resource for comparative genomic research in Phthiraptera and facilitates further studies on adaptive evolution of host-switching within parasitic lice.


Assuntos
Amblíceros , Parasitos , Animais , Aves Domésticas , Cromossomos , Mamíferos
8.
RSC Adv ; 13(42): 29689-29694, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37822652

RESUMO

A series of sulfonate anions paired aromatic triangular palladium clusters 3-7, abbreviated as [Pd3]+[ArSO3]-, were synthesized using a simple "one pot" method, and gave excellent isolated yields (90-95%). Their structures and properties have been fully characterized and further investigated by fluorescence, single crystal X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). In varying organic solvents, they presented apparently stronger absorption and emission in MeOH, driven by the combined interactions of hydrogen bonds and polarity. The crystallographic data demonstrated that the methyl orange ion stabilized complex 7 possessed a D3h symmetric metallic core which was still coplanar and almost equilateral, jointly influenced by the giant hindrance and milder donating effect from the sulfonate. The binding energies for Pdn+ 3d5/2 and Pdn+ 3d3/2 measured by XPS presented at 336.55 and 342.00 eV, respectively. These data were much lower than that of a usual Pd2+ 3d and significantly higher than that of a Pd0 species, further proving the unified palladium valence state (+4/3) in the tri-palladium core and its aromaticity featured by the cyclic electron delocalization.

9.
J Dermatolog Treat ; 34(1): 2229464, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37394952

RESUMO

INTRODUCTION: Atopic dermatitis (AD) exhibits difference in immune polarization between Caucasians and Asian races due to which an evaluation of the efficacy and safety of Pimecrolimus (PIM) in Asian population is called for. The current study addresses the need via a sub-group analysis of the PETITE study (NCT00120523) to evaluate the safety and efficacy of PIM in Chinese infants. MATERIALS AND METHODS: Patients with AD (≥3 months-<12 months of age) were randomized in a 1:1 ratio to either PIM 1% cream or topical corticosteroids (TCS). The primary endpoint was safety. The secondary endpoint was efficacy. RESULTS: 120 patients were randomized to either PIM 1% or TCS (n = 61 for PIM, n = 59 for TCS). The most often reported adverse events were reported by similar proportions of patients treated with PIM or TCS. There was a progressive increase in overall IGA treatment success in infants treated with PIM (82.9%, p < .05, 95% CI: 70.4, 95.3) after 26 weeks which was comparable to the TCS group (88.5%, p < .05, 95% CI: 79.8, 97.1). CONCLUSION: PIM showed an early and sustained efficacy in the Chinese sub-population with a substantial corticosteroid-sparing effect in patients with AD.


Assuntos
Dermatite Atópica , Fármacos Dermatológicos , Tacrolimo , Humanos , Lactente , Dermatite Atópica/tratamento farmacológico , Fármacos Dermatológicos/administração & dosagem , Fármacos Dermatológicos/efeitos adversos , Fármacos Dermatológicos/uso terapêutico , População do Leste Asiático , Tacrolimo/administração & dosagem , Tacrolimo/efeitos adversos , Tacrolimo/análogos & derivados , Tacrolimo/uso terapêutico , Resultado do Tratamento , Administração Tópica , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Creme para a Pele
10.
Zootaxa ; 5124(5): 585-593, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35391099

RESUMO

Here we report two new species of the swordtail crickets (Orthoptera: Trigonidiidae; Trigonidiinae) from Yunnan and Guangxi Province, China. One species (Trigonidium rubrumoculus sp. nov.) belongs to the genus Trigonidium, and we describe a new genus for the other species (Polycomus gen. nov., Polycomus exspiravit sp. nov.). The new genus resembles Amusurgus Brunner von Wattenwyl, 1893 in appearance but differs in the structure of the male genitalia. Descriptions, illustrations, and distributions of these new species are provided.


Assuntos
Gryllidae , Ortópteros , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , China , Masculino , Tamanho do Órgão
11.
Zootaxa ; 5092(4): 473-479, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35391191

RESUMO

Here we describe two new species of ground crickets from Yunnan Province, China (Homonemobius brevipennis sp. nov. and Pteronemobius osuviridis sp. nov.). Descriptions, illustrations, and distributions of these new species are provided.


Assuntos
Gryllidae , Ortópteros , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , China , Tamanho do Órgão
12.
Zookeys ; 1090: 113-128, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35586841

RESUMO

We propose the genus Flospes gen. nov. for two new species, Flospesguangxiensis sp. nov. and Flospesviridipennis sp. nov., obtained from Guangxi and Hainan provinces, China, respectively, based on male genitalia traits. Three other species with similar genitalia are placed in the new genus: Flospesfujianensis (Wang et al., 1999), comb. nov., Flospeshainanensis (He et al., 2010), comb. nov., and Flospesdenticulatus (Liu & Shi, 2011), comb. nov. The new species are described, illustrated, and their ranges are given.

13.
Toxicol Res (Camb) ; 11(4): 628-643, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36051664

RESUMO

Arsenic, a widely existing environmental contaminant, is recognized to be toxic to multiple organs. Exposure to arsenic results in liver damage via excessive production of reactive oxidative species (ROS). PIN1 regulates the levels of ROS. N-acetyl-L-cysteine (NAC) is an ROS scavenger that protects the hepatic functions. Whether PIN1 plays a regulatory role in NAC-mediated antagonism against arsenic hepatotoxicity remains largely unknown. In our study, the protective effects of NAC against arsenic (NaAsO2)-induced hepatotoxicity were evaluated in vitro and in vivo. Arsenic exposure induced cytotoxicity by increasing the intracellular ROS production, impairing mitochondrial function and inducing apoptosis in L02 hepatocytes. Overexpression of PIN1 markedly protected against arsenic cytotoxicity, decreased ROS levels, and mitigated mitochondrial dysfunction and apoptosis in L02 cells. However, loss of PIN1 further aggravated arsenic-induced cytotoxicity and abolished the protective effects of NAC in L02 cells. An in vivo study showed that pretreatment with NAC rescued arsenic-induced liver injury by restoring liver function and suppressing hepatic oxidative stress. Overexpression of PIN1 in mice transfected with AAV-Pin1 relieved arsenic-induced liver dysfunction and hepatic oxidative stress. Taken together, our study identified PIN1 as a novel intervention target for antagonizing arsenic-induced hepatotoxicity, highlighting a new pharmacological mechanism of NAC targeting PIN1 in antagonism against arsenic toxicity.

14.
Dalton Trans ; 51(22): 8786-8794, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35616208

RESUMO

The Li2MoO3 (LMO) material is one promising cathode material for lithium-ion batteries due to its high specific capacity and absence of oxygen release. However, its surface instability in air and poor conductivity have limited its application. To solve these problems, the Ru element has been successfully introduced into the LMO lattice with the aid of the molten salt method. XRD and TEM characterization showed that the introduction of Ru does not change the crystal structure but expands the crystal plane spacing of the {001} facets, which is further evidenced by density functional theory (DFT) calculations. XPS and EDS tests indicated that the introduction of Ru inhibits the oxidation of Mo species and leads to a more uniform distribution of the material. In addition, DFT calculations revealed that covalent interactions are formed between Mo4d/Ru4d and O2p orbitals, leading to a significant reduction of the band gap. Therefore, Ru-doped samples exhibit good electrochemical performances. The initial discharge capacity of an LMRO-2 sample reaches 299.1 mA h g-1 at a 1C rate, and the capacity remains at 125.2 mA h g-1 after 100 cycles. In comparison, the initial discharge capacity of pure phase sample LMO is only 250.5 mA h g-1 under the same conditions, and the capacity remains only at 76.5 mA h g-1 after 100 cycles. The present results confirmed that Ru doping is an effective strategy to improve the performance of the LMO cathode material.

15.
J Hazard Mater ; 435: 128942, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35468398

RESUMO

Metabolic disorders induced by arsenic exposure have attracted great public concern. However, it remains unclear whether hypothalamus-based central regulation mechanisms are involved in this process. Here, we exposed mice to 100 µg/L arsenic in drinking water and established a chronic arsenic exposure model. Our study revealed that chronic arsenic exposure caused metabolic disorders in mice including impaired glucose metabolism and decreased energy expenditure. Arsenic exposure also impaired glucose sensing and the activation of proopiomelanocortin (POMC) neurons in the hypothalamus. In particular, arsenic exposure damaged the plasticity of hypothalamic astrocytic process. Further research revealed that arsenic exposure inhibited the expression of sex-determining region Y-Box 2 (SOX2), which decreased the expression level of insulin receptors (INSRs) and the phosphorylation of AKT. The conditional deletion of astrocytic SOX2 exacerbated arsenic-induced effects on metabolic disorders, the impairment of hypothalamic astrocytic processes, and the inhibition of INSR/AKT signaling. Furthermore, the arsenic-induced impairment of astrocytic processes and inhibitory effects on INSR/AKT signaling were reversed by SOX2 overexpression in primary hypothalamic astrocytes. Together, we demonstrated here that chronic arsenic exposure caused metabolic disorders by impairing SOX2-modulated hypothalamic astrocytic process plasticity in mice. Our study provides evidence of novel central regulatory mechanisms underlying arsenic-induced metabolic disorders and emphasizes the crucial role of SOX2 in regulating the process plasticity of adult astrocytes.


Assuntos
Arsênio , Doenças Metabólicas , Animais , Arsênio/metabolismo , Arsênio/toxicidade , Hipotálamo/metabolismo , Doenças Metabólicas/metabolismo , Camundongos , Pró-Opiomelanocortina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
16.
Zootaxa ; 4942(3): zootaxa.4942.3.4, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33757058

RESUMO

The Itarinae includes two genera and 60 species world-wide. Ten species are recorded from China. All Chinese species were reviewed in this study. Females of the most species were described and illustrated. Keys based on characters of male and female for Chinese species were provided respectively. As well as, a new species and revised species distribution of Itara Walker, 1869 were reported. Two types of coloration (dark and light colors) of Parapentacentrus fuscus Gorochov, 1988 were discovered and taxonomic problem of the genus Parapentacentrus Shiraki, 1930 were discussed.


Assuntos
Gryllidae , Ortópteros , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , China , Feminino , Masculino , Tamanho do Órgão
17.
Zootaxa ; 5011(1): 1-70, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34810470

RESUMO

The article reviewed species of genera of Pteronemobius Jacobson, 1904, Speonemobius Chopard, 1924, Parapteronemobius Furukawa, 1970, Dianemobius Vickery, 1973, Polionemobius Gorochov, 1983, Giganemobius Shen He, 2020, Qionemobius Shen He, 2020 and proposed four new genera, Claranemobius He Ma, gen. n., Erexitonemobius He Ma, gen. n., Fibunemobius He Ma, gen. n. and Impetunemobius He Ma, gen. n., and nine new species, Claranemobius yaoquensis He Ma, sp. n., Erexitonemobius bellus He Ma, sp. n., Fibunemobius tamquam He Ma, sp. n., Homonemobius amare He Ma, sp. n., Impetunemobius brunneis He Ma, sp. n., Polionemobius Chayuensis He Ma, sp. n., Pteronemobius (Pteronemobius) litore He Ma, sp. n., Pteronemobius (Pteronemobius) choui He Ma, sp. n. and Speonemobius minor He Ma, sp. n..


Assuntos
Gryllidae , Ortópteros , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , China , Tamanho do Órgão
18.
Zootaxa ; 4950(3): zootaxa.4950.3.11, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33903434

RESUMO

A new species, Rhicnogryllus nanlingensis sp. n., was reported from Guangdong, China. This was the first time of Rhicnogryllus was recorded from China. Description and illustrations for the new species were provided.


Assuntos
Gryllidae , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , China , Gryllidae/classificação , Tamanho do Órgão , Ortópteros
19.
Zootaxa ; 4942(1): zootaxa.4942.1.3, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33756911

RESUMO

The genus Ornebius Guérin-Méneville, 1844 was divided into five species groups based on the structure of the male genitalia. Three new species of Ornebius were described from the Chinese provinces of Hainan, Guangxi and Guangdong. Type specimens are deposited at the Museum of Flora and Fauna of Shaanxi Normal University, Xi'an, China (SNNU).


Assuntos
Gryllidae , Ortópteros , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , China , Masculino , Tamanho do Órgão
20.
ACS Appl Mater Interfaces ; 13(28): 33272-33281, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34242016

RESUMO

Advanced ferroelectrics with a combination of large dielectric response and good temperature stability are crucial for many technologically important electronic devices and electrical storage/power equipment. However, the two key factors usually do not go hand in hand, and achieving high permittivity is normally at the expense of sacrificing temperature stability. This trade-off relation is eased but not fundamentally remedied using relaxor-type materials which are known to have a diffuse permittivity peak at their relaxor transition temperatures. Here, we report an anomalous trirelaxor phenomenon in a barium titanate system and show that it can lead to a giant dielectric permittivity (εr ≈ 18 000) over a wide temperature range (Tspan ≈ 34K), which successfully overcomes a long-standing permittivity-stability trade-off. Moreover, the enhancement in the dielectric properties also yields a desired temperature-insensitive electrocaloric performance for the trirelaxor ferroelectrics. Microstructure characterization and phase-field simulations reveal a mixture of tetragonal, orthorhombic, and rhombohedral polar nanoregions over a broad temperature window in trirelaxor ferroelectrics, which is responsible for this combination of giant dielectric permittivity and good temperature stability. This finding provides an effective approach in designing advanced ferroelectrics with high performance and thermal stability.

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