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1.
J Am Chem Soc ; 146(13): 9434-9443, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38507716

RESUMO

Electrocatalytic synthesis of hydrogen peroxide (H2O2) in acidic media is an efficient and eco-friendly approach to produce inherently stable H2O2, but limited by the lack of selective and stable catalysts under industrial-relevant current densities. Herein, we report a diatomic cobalt catalyst for two-electron oxygen reduction to efficiently produce H2O2 at 50-400 mA cm-2 in acid. Electrode kinetics study shows a >95% selectivity for two-electron oxygen reduction on the diatomic cobalt sites. In a flow cell device, a record-high production rate of 11.72 mol gcat-1 h-1 and exceptional long-term stability (100 h) are realized under high current densities. In situ spectroscopic studies and theoretical calculations reveal that introducing a second metal into the coordination sphere of the cobalt site can optimize the binding strength of key H2O2 intermediates due to the downshifted d-band center of cobalt. We also demonstrate the feasibility of processing municipal plastic wastes through decentralized H2O2 production.

2.
J Inflamm Res ; 17: 1057-1082, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38375021

RESUMO

As the body's largest organ, the skin harbors a highly diverse microbiota, playing a crucial role in resisting foreign pathogens, nurturing the immune system, and metabolizing natural products. The dysregulation of human skin microbiota is implicated in immune dysregulation and inflammatory responses. This review delineates the microbial alterations and immune dysregulation features in common Inflammatory Skin Diseases (ISDs) such as psoriasis, rosacea, atopic dermatitis(AD), seborrheic dermatitis(SD), diaper dermatitis(DD), and Malassezia folliculitis(MF).The skin microbiota, a complex and evolving community, undergoes changes in composition and function that can compromise the skin microbial barrier. These alterations induce water loss and abnormal lipid metabolism, contributing to the onset of ISDs. Additionally, microorganisms release toxins, like Staphylococcus aureus secreted α toxins and proteases, which may dissolve the stratum corneum, impairing skin barrier function and allowing entry into the bloodstream. Microbes entering the bloodstream activate molecular signals, leading to immune disorders and subsequent skin inflammatory responses. For instance, Malassezia stimulates dendritic cells(DCs) to release IL-12 and IL-23, differentiating into a Th17 cell population and producing proinflammatory mediators such as IL-17, IL-22, TNF-α, and IFN-α.This review offers new insights into the role of the human skin microbiota in ISDs, paving the way for future skin microbiome-specific targeted therapies.

3.
RSC Adv ; 14(3): 1527-1537, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38179095

RESUMO

Periodontitis can lead to defects in the alveolar bone, thus increasing the demand for dependable biomaterials to repair these defects. This study aims to examine the pro-osteogenic and anti-bacterial properties of UPPE/ß-TCP/TTC composites (composed of unsaturated polyphosphoester [UPPE], ß-tricalcium phosphate [ß-TCP], and tetracycline [TTC]) under an inflammatory condition. The morphology of MC3T3-E1 cells on the composite was examined using scanning electron microscopy. The toxicity of the composite to MC3T3-E1 cells was assessed using the Alamar-blue assay. The pro-osteogenic potential of the composite was assessed through ALP staining, ARS staining, RT-PCR, and WB. The antimicrobial properties of the composite were assessed using the zone inhibition assay. The results suggest that: (1) MC3T3-E1 cells exhibited stable adhesion to the surfaces of all four composite groups; (2) the UPPE/ß-TCP/TTC composite demonstrated significantly lower toxicity to MC3T3-E1 cells; and (3) the UPPE/ß-TCP/TTC composite had the most pronounced pro-osteogenic effect on MC3T3-E1 cells by activating the WNT/ß-catenin pathway and displaying superior antibacterial properties. UPPE/ß-TCP/TTC, as a biocomposite, has been shown to possess antibacterial properties and exhibit excellent potential in facilitating osteogenic differentiation of MC3T3-E1 cells.

4.
5.
Nat Commun ; 14(1): 7312, 2023 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-37951992

RESUMO

Enveloped viruses encased within a lipid bilayer membrane are highly contagious and can cause many infectious diseases like influenza and COVID-19, thus calling for effective prevention and inactivation strategies. Here, we develop a diatomic iron nanozyme with lipoxidase-like (LOX-like) activity for the inactivation of enveloped virus. The diatomic iron sites can destruct the viral envelope via lipid peroxidation, thus displaying non-specific virucidal property. In contrast, natural LOX exhibits low antiviral performance, manifesting the advantage of nanozyme over the natural enzyme. Theoretical studies suggest that the Fe-O-Fe motif can match well the energy levels of Fe2 minority ß-spin d orbitals and pentadiene moiety π* orbitals, and thus significantly lower the activation barrier of cis,cis-1,4-pentadiene moiety in the vesicle membrane. We showcase that the diatomic iron nanozyme can be incorporated into air purifier to disinfect airborne flu virus. The present strategy promises a future application in comprehensive biosecurity control.


Assuntos
Alcadienos , Influenza Humana , Vírus , Humanos , Antivirais , Lipoxigenase , Ferro
6.
Chem Sci ; 14(24): 6558-6563, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37350822

RESUMO

Catalytic depolymerization represents a promising approach for the closed-loop recycling of plastic wastes. Here, we report a knowledge-driven catalyst development for poly(ethylene terephthalate) (PET) recycling, which not only achieves more than 23-fold enhancement in specific activity but also reduces the alkali concentration by an order of magnitude compared with the conventional hydrolysis. Substituted binuclear zinc catalysts are developed to regulate biomimetic intramolecular PET hydrolysis. Hammett studies and density functional theory (DFT) calculations indicate that the substituents modify the charge densities of the active centers, and an optimal substituent should slightly increase the electron richness of the zinc sites to facilitate the formation of a six-membered ring intermediate. The understanding of the structure-activity relationship leads to an advanced catalyst with a specific activity of 778 ± 40 gPET h-1 gcatal-1 in 0.1 M NaOH, far outcompeting the conventional hydrolysis using caustic bases (<33.3 gPET h-1 gcatal-1 in 1-5 M NaOH). This work opens new avenues for environmentally benign PET recycling.

7.
Plant Divers ; 45(2): 133-146, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37069933

RESUMO

Three woody bamboo species collected in Hainan, China in 1940 have been described as Dinochloa based on vegetative specimens. However, the identity of these species has long been in doubt, largely because the vegetative phase in species of Dinochloa is morphologically similar to that in species of Melocalamus, a climbing or scrambling bamboo genus of the paleotropical woody bamboos (Poaceae: Bambusoideae) that consists of about 15 species and one variety. To determine the phylogenetic affinity of the three Dinochloa species from Hainan, we sampled almost all recognized Chinese species of Melocalamus and representative species of Dinochloa as well as other closely related genera, performed molecular phylogenetic analysis, and compared their morphology based on herbarium and fieldwork investigation. Our ddRAD data indicate that the three species from Hainan are closely related to Melocalamus, not Dinochloa. Morphological analysis showed that these three species have a climbing habit but do not grow spirally, their culm leaves have smooth bases, and there is a ring of powder and/or tomenta above and below the nodes. Taken together our findings indicate that the three species from Hainan originally published in Dinochloa should be transferred to Melocalamus, i.e., Melocalamus orenudus (McClure) D.Z. Li & J.X. Liu, Melocalamus puberulus (McClure) D.Z. Li & J.X. Liu, and Melocalamus utilis (McClure) D.Z. Li & J.X. Liu, respectively. This study concludes with an enumeration of Chinese species of Melocalamus, with a key to nine recognized species and one variety, and a lectotypification for M. compatiflorus.

8.
J Am Chem Soc ; 145(8): 4819-4827, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36790150

RESUMO

Heterogeneous catalysts containing diatomic sites are often hypothesized to have distinctive reactivity due to synergistic effects, but there are limited approaches that enable the convenient production of diatomic catalysts (DACs) with diverse metal combinations. Here, we present a general synthetic strategy for constructing a DAC library across a wide spectrum of homonuclear (Fe2, Co2, Ni2, Cu2, Mn2, and Pd2) and heteronuclear (Fe-Cu, Fe-Ni, Cu-Mn, and Cu-Co) bimetal centers. This strategy is based on an encapsulation-pyrolysis approach, wherein a porous material-encapsulated macrocyclic complex mediates the structure of DACs by preserving the main body of the molecular framework during pyrolysis. We take the oxygen reduction reaction (ORR) as an example to show that this DAC library can provide great opportunities for electrocatalyst development by unlocking an unconventional reaction pathway. Among all investigated sites, Fe-Cu diatomic sites possess exceptional high durability for ORR because the Fe-Cu pairs can steer elementary steps in the catalytic cycle and suppress the troublesome Fenton-like reactions.

9.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(10): 1154-1160, 2022 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-36305118

RESUMO

OBJECTIVES: To investigate the sleep patterns and characteristics of infants and young children and the association between sleep patterns and breastfeeding. METHODS: A general information questionnaire, Brief Infant Sleep Questionnaire (BISQ), and a questionnaire on feeding were used to investigate the sleep quality and feeding patterns of 1 148 infants and young children aged 7-35 months. The K-means clustering method was used to identify sleep patterns and characteristics. A multivariate logistic regression analysis was used to investigate the association between sleep patterns and breastfeeding. RESULTS: Three typical sleep patterns were identified for the 1 148 infants and young children aged 7-35 months: early bedtime and long sleep time; short sleep latency and moderate sleep time; late bedtime, prolonged sleep latency, and insufficient sleep time. The third pattern showed sleep disorders. The multivariate logistic regression analysis showed that compared with formula feeding, exclusive breastfeeding within 6 months after birth reduced the risk of sleep disorder patterns by 69% (OR=0.31, 95%CI: 0.11-0.81). The risk of sleep disorder patterns was reduced by 40% (OR=0.60, 95%CI: 0.38-0.96) in the infants receiving breastfeeding for 4-6 months compared with those receiving breastfeeding for 1-3 months. CONCLUSIONS: There are different sleep patterns in infants and young children, and breastfeeding can reduce the development of sleep disorder patterns.


Assuntos
Aleitamento Materno , Transtornos do Sono-Vigília , Lactente , Criança , Feminino , Humanos , Pré-Escolar , Inquéritos e Questionários , Sono , Análise por Conglomerados
10.
J Cardiothorac Surg ; 17(1): 240, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36171612

RESUMO

BACKGROUND: Primary pulmonary osteosarcoma (PPOS) is an uncommon malignancy originating from the lung with low incidence, and its clinical characteristics and prognosis have not been systematically reported. Therefore, we aimed to recognize the prognostic factors and constructed a survival prediction model for PPOS. METHODS: We collected the data from the Surveillance, Epidemiology, and End Results database and systematic review of previous studies. Demographical and clinical characteristics, radiographic manifestations, treatment modalities, and prognosis were analyzed. A prediction model via nomogram was constructed and then evaluated by the concordance index (C-index) and the receiver operating characteristic (ROC) curve. RESULTS: A total of 49 cases were included for analysis with a median age of 67 years old (range 33-94 years), of which 32 (65.3%) were male. The median size was 6 cm (range 1.8-25 cm), and the median overall survival (OS) was eight months (interquartile range 4.5-12 months) with a 1-year OS rate of 30.8%. Tumor size over 7 cm (hazard ratio [HR] = 2.98; P = 0.018) and those without microscopic findings of osteoid found in the tumors (HR = 2.11; P = 0.048) were referred to a poor OS, while surgery was associated with an improved OS (HR = 0.20; P < 0.001). The C-index of the nomogram prediction model was 0.771, and the area under curve, sensitivity and specificity of the ROC curve were 0.818, 0.848 and 0.800, respectively. CONCLUSIONS: Patients with PPOS had a poor prognosis, and tumor size was mostly prognostic. Surgery seemed to be an effective treatment, and the prediction model with a nomogram in our study could effectively predict the prognosis of patients with PPOS.


Assuntos
Pulmão , Osteossarcoma , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Osteossarcoma/diagnóstico , Prognóstico , Programa de SEER
11.
BMC Surg ; 22(1): 100, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35303836

RESUMO

BACKGROUND: It is a big challenge to repair a large abdominal wall defect after tumor resection, and en bloc resection with vascularized tissue reconstruction might be an alternative to achieve an improved survival for abdominal wall tumors. CASE PRESENTATION: A 45-year-old woman presented with a 1-year history of persistent abdominal pain of the right lower quadrant and a mass with dermal ulceration. An enhanced computed tomography scan and biopsy of the mass were performed to achieve the definite diagnosis of abdominal mucinous adenocarcinoma. After four courses of "FOLFOX" chemotherapy, the tumor grew to 6 × 5 cm during preoperative examination. Thereafter, we removed the tumor and involved tissues and organs and repaired the sizeable abdominal wall defect used by biological meshes and vascularized anterolateral thigh flaps. The patient suffered green drainage of 450 ml in the abdominal cavity and intestinal anastomotic fistula, for which she readmitted and recovered afterward. CONCLUSIONS: Biological mesh combined with vascularized anterolateral thigh flaps could effectively repair the large abdominal wall defect and restore the biological function of the abdominal wall.


Assuntos
Parede Abdominal , Adenocarcinoma Mucinoso , Procedimentos de Cirurgia Plástica , Parede Abdominal/cirurgia , Adenocarcinoma Mucinoso/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/cirurgia , Coxa da Perna/cirurgia
12.
Front Oncol ; 12: 830470, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35280762

RESUMO

Purpose: To compare the survival difference among lobectomy, segmentectomy, and wedge resection and investigate the role of adjuvant chemotherapy for early-stage small-sized non-small cell lung cancer (NSCLC) with visceral pleural invasion (VPI). Methods: Patients diagnosed with stage IB peripheral NSCLC with VPI and ≤3 cm in size in the Surveillance, Epidemiology, and End Results database between 2004 and 2015 were included, and the pleural layer (PL) invasion status was identified to recognize the tumors with VPI, including PL1 and PL2. We conducted Cox proportional hazards model in multivariable analysis and subgroup analysis via propensity score matching (PSM) method and Cox regression method to figure out the optimal therapy for these patients. Results: A total of 1,993 patients were included, all of whom received surgery, and the median follow-up was 33 months (range, 1-83 months). In multivariable analysis, age, gender, histology, pathological grade, lymph node examination, surgical approaches, and radiotherapy were independent prognostic factors for overall survival (OS). Lobectomy was superior to sublobar resection [hazard ratio (HR) = 1.41; 95% CI, 1.08-1.83], and wedge resection was associated with impaired survival compared to lobectomy (HR = 1.64; 95% CI, 1.22-2.20) in PSM analyses. In subgroup analysis, lobectomy was superior to sublobar resection among those aged <70 years (HR = 1.81; 95% CI, 1.13-2.90), female (HR = 1.75; 95% CI, 1.21-2.53), and 1-20 mm in size (HR = 1.61; 95% CI, 1.11-2.33). No survival benefit was observed for adjuvant chemotherapy. Conclusions: Lobectomy was superior to wedge resection and comparable with segmentectomy for stage IB NSCLC (≤3 cm) with VPI, and adjuvant chemotherapy could not benefit these patients, even in those with sublobar resection. The preferred surgical procedure remains to be studied in prospective controlled trials.

13.
Plant Divers ; 43(6): 492-501, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35024518

RESUMO

Two new species of Yushania (Poaceae, Bambusoideae, Arundinarieae) are described and illustrated from Hunan, China. Yushania longshanensis D.Z. Li & X.Y. Ye is distinguished from related species (Y. confusa, Y. angustifolia and Y. pachyclada) by having a thinner culm (0.2-0.3 cm in diameter), glabrous sheath scar, no oral setae, a large glabrous leaf blade (10-20 × 0.9-1.3 cm) and 3-4 pairs of secondary veins. Yushania stoloniforma D.Z. Li & X.Y. Ye has a distinctive scrambling habit, which differs from its putative close allies. Both of these two new species have a solitary branch at the basal nodes and can be assigned to Yushania sect. Yushania based on morphological features. Additionally, we treated Yushania gigantea T.P. Yi & L. Yang as a new synonym of Y. elevata T.P. Yi and renamed Y. microphylla T.P. Yi & L. Yang as Y. weiningensis D.Z. Li & X.Y. Ye.

14.
PhytoKeys ; 170: 25-37, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33363433

RESUMO

Two new species of Fargesia, one from Xizang (Tibet) and one from Yunnan, China, are described and illustrated. Fargesia viridis D.Z. Li & X.Y. Ye is characterized by its densely white powder, nearly solid internodes, yellow setose sheath scar and culm sheaths, and 4-6 leaves of large size. Fargesia purpurea D.Z. Li & X.Y. Ye has thinner culms (0.5-1.4 cm in diameter), a ring of 4-5 mm tall brown setae below nodes, fewer branches, glabrous sheath scar and culm sheaths, differentiated from the related species.

15.
Plant Divers ; 42(3): 127-134, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32695944

RESUMO

A new subtribal classification of the woody bamboo tribe Arundinarieae is proposed based on recent phylogenomic studies. Five subtribes, corresponding to the five major lineages of the ddRAD-seq based phylogenomic trees, are recognised: Arundinariinae (the leptomorph lineage), Ampelocalaminae (the ADH lineage), Gaoligongshaniinae (represented by Gaoligongshania), Hsuehochloinae (represented by Hsuehochloa) and Thamnocalaminae (the pachymorph lineage, i.e., alpine bamboos). Subtribes Ampelocalaminae, Gaoligongshaniinae and Hsuehochloinae are newly established, while the circumscriptions of subtribes Arundinariinae and Thamnocalaminae differ from the traditional classification. Subtribe Arundinariinae also includes those taxa that were previous members of the subtribe Shibataeinae. Thus, among the five redefined subtribes, Arundinariinae is the most heterogenous in terms of morphology. In Arundinarieae, rhizome type has greater implications for classification than other vegetative and reproductive characters at the subtribal level. In addition, the new monotypic genus Ravenochloa is described on the basis of its morphological characteristics and geographical distribution to accommodate the unique phylogenetic entity of Indocalamus wilsonii.

16.
Mol Phylogenet Evol ; 146: 106758, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32028031

RESUMO

The Bambusa-Dendrocalamus-Gigantochloa complex (BDG complex) is the most diversified and phylogenetically recalcitrant group of the paleotropical woody bamboos. Species of this complex occur in tropical and subtropical Asia and most of them are of great economic, cultural and ecological value. The lack of resolution achieved through the analyses of previous molecular datasets has long confounded its phylogenetic estimation and generic delimitation. Here, we adopted a ddRAD-seq strategy to investigate phylogenetic relationships of the four main genera (Bambusa, Dendrocalamus, Gigantochloa, and Melocalamus) in the BDG complex. A total of 102 species were sampled, and SNP data were generated. Both MP and ML analyses of the ddRAD-seq data resulted in a well-resolved topology with Gigantochloa and Melocalamus confirmed as monophyletic, and Melocalamus resolved as sister to the rest of the complex. Bambusa and Dendrocalamus were both resolved as paraphyletic. The phylogenetic relationships were mostly supported by morphological evidence including characters of the branch complement, rachilla, lodicules, filaments and stigma. We also generated and assembled complete plastid genomes of 48 representative species. There were conflicts between the plastome and the ddRAD topologies. Our study demonstrated that RAD-seq can be used to reconstruct evolutionary history of lineages such as the bamboos where ancient hybridization and polyploidy play a significant role. The four genera of the BDG complex have a complex evolutionary history which is likely a product of ancient introgression events.


Assuntos
Bambusa/classificação , Poaceae/classificação , Ásia , Bambusa/genética , Evolução Biológica , Genomas de Plastídeos , Hibridização Genética , Filogenia , Poaceae/anatomia & histologia , Poaceae/genética , Polimorfismo de Nucleotídeo Único , Poliploidia , Análise de Sequência de DNA
17.
Dalton Trans ; 49(12): 3672-3675, 2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-31657402

RESUMO

Two new isostructural non-centrosymmetric cerium iodates KxCe9(IO3)36 (x≈ 3) and LaxCe9(IO3)36 (x≈ 0.3) were synthesized via a hydrothermal method and systematically characterized. They are intermediate valence compounds with the same band gap, showing similar microscopic net dipole moments per unit volume, but different macroscopic second-harmonic generation (SHG) responses under 1064 nm laser irradiation. This research gives a new view for understanding the effects of electronic structure on the SHG response.

18.
Mitochondrial DNA B Resour ; 5(3): 2320-2321, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33457774

RESUMO

Dendrocalamus hamiltonii is one of the best bamboo species with bamboo shoots, and has higher economic value. The chloroplast genome is a circular molecule of 139404 bp in length, consisting of a 82938 bp large single copy region (LSC), a 12876 bp small single copy region (SSC), and a pair of inverted repeats region (IRa and IRb: 21795 bp each). The GC content of chloroplast genome is 38.9%. The cp genome contains a total of 133 genes, including 86 protein-coding genes, 8 rRNA genes, and 39 tRNA genes. Moreover, phylogenomic analysis showed that D. hamiltonii and D. brandisii clustered together in one branch.

19.
Dalton Trans ; 48(47): 17588-17593, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31750843

RESUMO

Inorganic chalcohalides have emerged as promising functional materials for a range of applications. However, most of them are chlorides and bromides, while iodides are still rare. Herein, a new quaternary iodine-based chalcohalide Ba3GaS4I has been acquired by the reaction of BaS, Ga, S and BaI2 at 1173 K. Single-crystal XRD analysis reveals that Ba3GaS4I has a centrosymmetric structure (orthorhombic, space group Cmcm, a = 6.991(3) Å, b = 15.910(7) Å, c = 9.698(4) Å, V = 1078.6(7) Å3, and Z = 4) and consists of isolated [GaS4] tetrahedra with charge-balanced Ba2+ cations and I- anions. Ba3GaS4I can be regarded as the product of chemical substitution of Ba3GaS4X (X = Cl, Br), which adopts a different space group, Pnma. The influences of the halogen elements on the bandgap and birefringence have been discussed through first principles calculations and structural comparison.

20.
PhytoKeys ; 130: 135-141, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534401

RESUMO

Yushania tongpeii D.Z.Li, Y.X.Zhang & E.D.Liu, a new species of the temperate bamboo tribe Arundinarieae (Poaceae: Bambusoideae), is described and illustrated from north-eastern Yunnan, China. Yushania tongpeii is characterised by taller branching from nodes 1-2 m above the ground, usually three branches at the node, sparse purple spots and thin white powder on the internode, densely purple-spotted culm sheaths, glabrous margins of culm sheaths and tomentose leaf ligules. Based on the morphological features, this new species is assigned to section Yushania.

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