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1.
Chem Soc Rev ; 52(16): 5652-5683, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37492961

RESUMO

Proton exchange membrane water electrolyzers (PEMWEs) are an attractive technology for renewable energy conversion and storage. By using green electricity generated from renewable sources like wind or solar, high-purity hydrogen gas can be produced in PEMWE systems, which can be used in fuel cells and other industrial sectors. To date, significant advances have been achieved in improving the efficiency of PEMWEs through the design of stack components; however, challenges remain for their large-scale and long-term application due to high cost and durability issues in acidic conditions. In this review, we examine the latest developments in engineering PEMWE systems and assess the gap that still needs to be filled for their practical applications. We provide a comprehensive summary of the reaction mechanisms, the correlation among structure-composition-performance, manufacturing methods, system design strategies, and operation protocols of advanced PEMWEs. We also highlight the discrepancies between the critical parameters required for practical PEMWEs and those reported in the literature. Finally, we propose the potential solution to bridge the gap and enable the appreciable applications of PEMWEs. This review may provide valuable insights for research communities and industry practitioners working in these fields and facilitate the development of more cost-effective and durable PEMWE systems for a sustainable energy future.

2.
Clin Lab ; 69(7)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37436386

RESUMO

BACKGROUND: In recent years, there have been increasing reports related to infection caused by Mycobacterium abscessus (MAB). As one of the most common mycobacterium iatrogenic infections, it is characterized by pulmonary infection. However, only a few reports of MAB-related skin and soft tissue infections are available. This study reported a 3-year-old child admitted to our hospital for a dog bite with MAB infection after debridement. METHODS: The diagnosis of MAB in this child was made after detecting the bacteria in the wound secretion based on secretion culture in clinical laboratory. RESULTS: The result of the first bacterial isolation and culture of wound secretion was negative. However, the results were positive two days later and was diagnosed as MAB infection for samples of the purulent secretions collected by puncture and aspiration during debridement from the red and swollen regions of the thigh. The drug sensitivity results suggested that the child was sensitive to cefoxitin. However, she was resistant to amikacin, linezolid, minocycline, imipenem, tobramycin, moxifloxacin, clarithromycin, and doxycycline. The combined treatment strategy was used for managing MAB infection with a good effect. CONCLUSIONS: The management of MAB soft tissue infection has limitations, like poor tolerance, toxicity, and mul¬ti-drug interaction. The combined treatment strategy is important for MAB infection, and monitoring adverse re-actions and toxicity is the key.


Assuntos
Antibacterianos , Infecções por Mycobacterium não Tuberculosas , Animais , Pré-Escolar , Cães , Feminino , Humanos , Amicacina/farmacologia , Antibacterianos/farmacologia , Claritromicina , Desbridamento , Testes de Sensibilidade Microbiana , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico
3.
Food Chem ; 413: 135643, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36773353

RESUMO

Methylation is a common structural modification of catechins in tea, which can improve the bioavailability of catechins. Flavoalkaloids are catechin derivatives with a nitrogen containing five-membered ring at the C-6 or C-8 position. Here we isolated three new methylated flavoalkaloids from Echa 1 green tea (Camellia sinensis cv. Echa 1) and synthesized another four new methylated flavoalkaloids. The structures of the new ester-type methylated catechins (etmc)-pyrrolidinone A-G (1-7) were elucidated by various spectroscopic techniques, including nuclear magnetic resonance (NMR), optical rotation, infrared, UV-vis, experimental and calculated circular dichroism (CD) spectra, and high-resolution mass. Among them, 6 and 7 showed the strongest α-glucosidase inhibitory activity and significantly lowered lipid content of Caenorhabditis elegans with 73.50 and 67.39% inhibition rate, respectively. Meanwhile, 6 and 7 also exhibited strong antioxidant activity in vitro and stress resistance to heat, oxidative stress, and UV irradiation in nematodes.


Assuntos
Camellia sinensis , Catequina , Animais , Chá/química , Caenorhabditis elegans , Camellia sinensis/química , Antioxidantes
4.
Food Funct ; 13(18): 9299-9310, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-35968754

RESUMO

Green tea polyphenols show positive effects on human health and longevity. However, knowledge of the antiaging properties of green tea is limited to the major catechin epigallocatechin gallate (EGCG). The search for new ingredients in tea with strong antiaging activity deserves further study. Here we isolated and identified two new catechins from Zijuan green tea, named zijuanin E (1) and zijuanin F (2). Their structures were identified by extensive high-resolution mass spectroscopy (HR-MS), nuclear magnetic resonance (NMR), ultraviolet-vis (UV), infrared (IR) and circular dichroism (CD) spectroscopic analyses, and their 13C NMR and CD data were calculated. We used the nematode Caenorhabditis elegans (C. elegans) to analyze the health benefits and longevity effects of 1 and 2. Compounds 1 and 2 (100 µM) remarkably prolonged the lifespan of C. elegans by 67.2% and 56.0%, respectively, delaying the age-related decline of phenotypes, enhancing stress resistance, and reducing ROS and lipid accumulation. Furthermore, 1 and 2 did not affect the lifespan of daf-16, daf-2, sir-2.1, and skn-1 mutant worms, suggesting that they might work via the insulin/IGF and SKN-1/Nrf2 signaling pathways. Meanwhile, 1 and 2 also exhibited strong antioxidant activity in vitro. Surface plasmon resonance (SPR) evidence suggests that zijuanins E and F have strong human serum albumin (HSA) binding ability. Together, zijuanins E and F represent a new valuable class of tea components that promote healthspan and could be developed as potential dietary therapies against aging.


Assuntos
Proteínas de Caenorhabditis elegans , Catequina , Animais , Antioxidantes/farmacologia , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Catequina/química , Insulina/metabolismo , Lipídeos/farmacologia , Longevidade , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Albumina Sérica Humana/metabolismo , Transdução de Sinais , Chá/química
5.
Front Plant Sci ; 13: 855944, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371115

RESUMO

Parnassia L., a perennial herbaceous genus in the family Celastraceae, consists of about 60 species and is mainly distributed in the Pan-Himalayan and surrounding mountainous regions. The taxonomic position and phylogenetic relationships of the genus are still controversial. Herein, we reassessed the taxonomic status of Parnassia and its intra- and inter-generic phylogeny within Celastraceae. To that end, we sequenced and assembled the whole plastid genomes and nuclear ribosomal DNA (nrDNA) of 48 species (74 individuals), including 25 species of Parnassia and 23 species from other genera of Celastraceae. We integrated high throughput sequence data with advanced statistical toolkits and performed the analyses. Our results supported the Angiosperm Phylogeny Group IV (APG IV) taxonomy which kept the genus to the family Celastraceae. Although there were topological conflicts between plastid and nrDNA phylogenetic trees, Parnassia was fully supported as a monophyletic group in all cases. We presented a first attempt to estimate the divergence of Parnassia, and molecular clock analysis indicated that the diversification occurred during the Eocene. The molecular phylogenetic results confirmed numerous taxonomic revisions, revealing that the morphological characters used in Parnassia taxonomy and systematics might have evolved multiple times. In addition, we speculated that hybridization/introgression might exist during genus evolution, which needs to be further studied. Similarly, more in-depth studies will clarify the diversification of characters and species evolution models of this genus.

6.
Front Cell Dev Biol ; 8: 333, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32457910

RESUMO

BACKGROUND: Lymphoma is a common hematological malignancy with many subtypes and considerable heterogeneity. Traditional treatments include chemotherapy, radiotherapy, and surgery. Patients with relapsed, refractory or advanced stage lymphoma have a dismal prognosis. In recent years, chimeric antigen receptors (CARs) have been recognized as powerful tools that redirect antigen-specific T cells independent of human lymphocyte antigen (HLA) restriction and specifically kill tumor cells. Satisfactory results with CAR-based treatments have been achieved in relapsed/refractory B cell leukemia/lymphoma. Our center explored the strategy of subcutaneous injections combined with intravenous drip to overcome certain issues. CASE PRESENTATION: A patient with stage IV refractory and relapsed diffuse large B cell lymphoma was treated with regional and intravenous CAR-T cells. During the observation period, the temperature of the skin at the abdominal wall mass was slightly elevated, and tolerable pain in the injection area was reported. Imaging showed regional liquefactive necrosis. After the sequential administration of ibrutinib and venetoclax, the abdominal wall mass significantly decreased in size. CONCLUSION: The regional injection of CAR-T cells might be safe and feasible for the treatment of regional lesions in patients with refractory and relapsed advanced lymphoma.

7.
Eur J Cancer Care (Engl) ; 28(2): e12987, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30614580

RESUMO

PURPOSE: The goal of our study was to evaluate the reliability, validity, responsiveness and acceptability of the Mandarin (simplified) Chinese version of the EORTC QLQ-OH45. METHODS: From October 2017 to February 2018, 393 cancer patients were enrolled from three different hospitals in China. A forward and backward translation was made to develop the Mandarin (simplified) Chinese version of EORTC QLQ-OH15. The QLQ-C30 and QLQ-OH15 questionnaires (which we have assembled and named QLQ-OH45 in this paper) were self-administered. Results were statistically analysed using SPSS 21.0. The reliability and validity tests of the questionnaires were assessed by Cronbach's α coefficient, Pearson correlation test and Mann-Whitney U tests. Responsiveness to change was measured in an independent sample of patients with head and neck cancer undergoing surgery or radiotherapy or chemotherapy. RESULTS: An acceptable internal consistency reliability for most multiple-item scales was demonstrated, as Cronbach's α coefficients were greater than 0.7 for most multiple-item scales, excepting for cognitive functioning (0.36) and oral health-related QoL functioning (0.55). All domain's test-retest reliability coefficients (r) was higher than 0.8. Multi-trait scaling analysis showed good convergent and discriminant validity. A difference in the quality of life (QoL) between older (≥65 years) and younger (<65 years) groups of patients was showed by the known-group comparisons. Low correlations were found between the scales of the QLQ-OH15 and QLQ-C30 in all areas. CONCLUSION: The Mandarin (simplified) Chinese version of QLQ-OH45 demonstrates satisfactory psychometric properties and can be used to measure the oral health-related QoL (OHRQoL) for Chinese cancer patients.


Assuntos
Neoplasias/etnologia , Inquéritos e Questionários , Adulto , Idoso , China/etnologia , Escolaridade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia , Saúde Bucal/etnologia , Psicometria , Qualidade da Assistência à Saúde , Reprodutibilidade dos Testes , Fatores Socioeconômicos , Traduções
8.
PLoS One ; 8(5): e64026, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23700450

RESUMO

Plants have evolved complex processes to ward off attacks by insects. In parallel, insects have evolved mechanisms to thwart these plant defenses. To gain insight into mechanisms that mediate this arms race between plants and herbivorous insects, we investigated the interactions between gramine, a toxin synthesized by plants of the family Gramineae, and glutathione S transferase (GST), an enzyme found in insects that is known to detoxify xenobiotics. Here, we demonstrate that rice (Oryza sativa), a hydrophytic plant, also produces gramine and that rice resistance to brown planthoppers (Nilaparvata lugens, BPHs) is highly associated with in planta gramine content. We also show that gramine is a toxicant that causes BPH mortality in vivo and that knockdown of BPH GST gene nlgst1-1 results in increased sensitivity to diets containing gramine. These results suggest that the knockdown of key detoxification genes in sap-sucking insects may provide an avenue for increasing their sensitivity to natural plant-associated defense mechanisms.


Assuntos
Alcaloides/metabolismo , Glutationa Transferase/metabolismo , Hemípteros/enzimologia , Proteínas de Insetos/metabolismo , Oryza/metabolismo , Adaptação Fisiológica , Animais , Técnicas de Silenciamento de Genes , Glutationa Transferase/genética , Herbivoria , Alcaloides Indólicos , Proteínas de Insetos/genética , Ninfa/enzimologia , Controle de Pragas , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Aumento de Peso
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