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1.
Chem Rev ; 123(16): 9915-9939, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37470246

RESUMO

Environmental concerns over waste plastics' effect on the environment are leading to the creation of biodegradable plastics. Biodegradable plastics may serve as a promising approach to manage the issue of environmental accumulation of plastic waste in the ocean and soil. Biodegradable plastics are the type of polymers that can be degraded by microorganisms into small molecules (e.g., H2O, CO2, and CH4). However, there are misconceptions surrounding biodegradable plastics. For example, the term "biodegradable" on product labeling can be misconstrued by the public to imply that the product will degrade under any environmental conditions. Such misleading information leads to consumer encouragement of excessive consumption of certain goods and increased littering of products labeled as "biodegradable". This review not only provides a comprehensive overview of the state-of-the-art biodegradable plastics but also clarifies the definitions and various terms associated with biodegradable plastics, including oxo-degradable plastics, enzyme-mediated plastics, and biodegradation agents. Analytical techniques and standard test methods to evaluate the biodegradability of polymeric materials in alignment with international standards are summarized. The review summarizes the properties and industrial applications of previously developed biodegradable plastics and then discusses how biomass-derived monomers can create new types of biodegradable polymers by utilizing their unique chemical properties from oxygen-containing functional groups. The terminology and methodologies covered in the paper provide a perspective on directions for the design of new biodegradable polymers that possess not only advanced performance for practical applications but also environmental benefits.


Assuntos
Plásticos Biodegradáveis , Plásticos Biodegradáveis/química , Polímeros/química , Biodegradação Ambiental , Biomassa
2.
Antimicrob Agents Chemother ; 68(10): e0095924, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39171918

RESUMO

Helicobacter pylori (H. pylori) is closely associated with the diseases such as gastric sinusitis, peptic ulcers, and gastric adenocarcinoma. Its drug resistance is very severe, and new antibiotics are urgently needed. Nine comfrey compounds were screened by antimicrobial susceptibility testing, among which deoxyshikonin had the best inhibitory effect, with a minimum inhibitory concentration (MIC) of 0.5-1 µg/mL. In addition, deoxyshikonin also has a good antibacterial effect in an acidic environment, it is highly safe, and H. pylori does not readily develop drug resistance. Through in vivo experiments, it was proven that deoxyshikonin (7 mg/kg) had a beneficial therapeutic effect on acute gastritis in mice infected with the multidrug-resistant H. pylori BS001 strain. After treatment with desoxyshikonin, colonization of H. pylori in the gastric mucosa of mice was significantly reduced, gastric mucosal damage was repaired, inflammatory factors were reduced, and the treatment effect was better than that of standard triple therapy. Therefore, deoxyshikonin is a promising lead drug to solve the difficulty of drug resistance in H. pylori, and its antibacterial mechanism may be to destroy the biofilm and cause an oxidation reaction.


Assuntos
Antibacterianos , Infecções por Helicobacter , Helicobacter pylori , Testes de Sensibilidade Microbiana , Helicobacter pylori/efeitos dos fármacos , Animais , Camundongos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Gastrite/tratamento farmacológico , Gastrite/microbiologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Antraquinonas/farmacologia , Masculino , Biofilmes/efeitos dos fármacos
3.
Nat Mater ; 22(1): 100-108, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36266572

RESUMO

Iridium-based electrocatalysts remain the only practical anode catalysts for proton exchange membrane (PEM) water electrolysis, due to their excellent stability under acidic oxygen evolution reaction (OER), but are greatly limited by their high cost and low reserves. Here, we report a nickel-stabilized, ruthenium dioxide (Ni-RuO2) catalyst, a promising alternative to iridium, with high activity and durability in acidic OER for PEM water electrolysis. While pristine RuO2 showed poor acidic OER stability and degraded within a short period of continuous operation, the incorporation of Ni greatly stabilized the RuO2 lattice and extended its durability by more than one order of magnitude. When applied to the anode of a PEM water electrolyser, our Ni-RuO2 catalyst demonstrated >1,000 h stability under a water-splitting current of 200 mA cm-2, suggesting potential for practical applications. Density functional theory studies, coupled with operando differential electrochemical mass spectroscopy analysis, confirmed the adsorbate-evolving mechanism on Ni-RuO2, as well as the critical role of Ni dopants in stabilization of surface Ru and subsurface oxygen for improved OER durability.

4.
Opt Lett ; 49(10): 2625-2628, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748121

RESUMO

We present an encoding scheme of a single logical qubit with single-sided quantum dot (QD)-cavity systems, which is immune to the collective decoherence. By adjusting the Purcell factor to satisfy the balanced reflection condition, the detrimental effects of unbalanced reflection between the coupled and uncoupled QD-cavity systems can be effectively suppressed. Furthermore, the fidelity of each step can be increased to unity regardless of the strong coupling regime and the weak coupling regime of cavity quantum electrodynamics (QED) with the assistance of waveform correctors. The scheme requires QD-cavity systems and simple linear optical elements, which can be implemented with the currently experimental techniques.

5.
Chemphyschem ; 25(16): e202400413, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-38747673

RESUMO

In order to explore the unique physiological roles of gas signaling molecules and gasotransmitters in vivo, chemists have engineered a variety of gas-responsive polymers that can monitor their changes in cellular milieu, and gas-releasing polymers that can orchestrate the release of gases. These have advanced their potential applications in the field of bio-imaging, nanodelivery, and theranostics. Since these polymers are of different chain structures and properties, the morphology of their assemblies will manifest distinct transitions after responding to gas or releasing gas. In this review, we summarize the fundamental design rationale of gas-responsive and gas-releasing polymers in structure and their controlled transition in self-assembled morphology and function, as well as present some perspectives in this prosperous field. Emerging challenges faced for the future research are also discussed.


Assuntos
Gases , Polímeros , Polímeros/química , Gases/química , Humanos
6.
Nanotechnology ; 35(36)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38865974

RESUMO

Significant efforts have been dedicated to designing porous organic cage compounds with geometric complexity and topological diversity. However, the use of these cage molecules as premade building units for constructing infinite cage-based superstructures remains unexplored. Here, we report the use of a panel-decorated phosphine organic cage as a special monomer to achieve supramolecular polymerization, resulting in cage-by-cage noncovalent polymers through the synergy of metal-coordination and intercageπ-πdimerization. At a monomer concentration of 122 mM, the average degree of polymerization reaches 17, corresponding to a molecular weight of 26 kDa. The obtained cage-based supramolecular polymers can further hierarchically self-assemble into vesicular morphologies or one-dimensional nanofiber architectures. Selective control over the cosolvents can regulate their structural hierarchy and assembled morphology. This approach paves a new way for the construction of cage-based hierarchical assemblies and materials.

7.
Mol Breed ; 44(9): 56, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39220047

RESUMO

Wheat is one of the most important staple foods in the world. Genetic characterization of wheat agronomically important traits is crucial for yield improvement through molecular breeding. In this study, a recombinant inbred line (RIL) population was developed by crossing a local adapted high yield variety Jimai 22 (JM22) with an external variety Cunmai no.1 (CM1). A high-density genetic map containing 7,359 single nucleotide polymorphism (SNP) markers was constructed. Quantitative trait loci (QTL) mapping identified 61 QTL for eight yield-related traits under six environments (years). Among them, 17 QTL affecting spike number per plant, grain number per spike and thousand grain weight showed high predictability for theoretical yield per plant (TYP), of which, 12 QTL alleles positively contributed to TYP. Nine promising candidate genes for seven of the 12 QTL were identified including three known wheat genes and six rice orthologs. Four elite lines with TYP increased by 5.6%-15.2% were identified through genotype selection which carried 7-9 favorable alleles from JM22 and 2-3 favorable alleles from CM1 of the 12 QTL. Moreover, the linked SNPs of the 12 QTL were converted to high-throughput kompetitive allele-specific PCR (KASP) markers and validated in the population. The mapped QTL, identified promising candidate genes, developed elite lines and KASP markers are highly valuable in future genotype selection to improve wheat yield. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01496-3.

8.
Int J Colorectal Dis ; 39(1): 100, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967814

RESUMO

BACKGROUND: Microsatellite instability (MSI) caused by DNA mismatch repair (MMR) deficiency is of great significance in the occurrence, diagnosis and treatment of colorectal cancer (CRC). AIM: This study aimed to analyze the relationship between mismatch repair status and clinical characteristics of CRC. METHODS: The histopathological results and clinical characteristics of 2029 patients who suffered from CRC and underwent surgery at two centers from 2018 to 2020 were determined. After screening the importance of clinical characteristics through machine learning algorithms, the patients were divided into deficient mismatch repair (dMMR) and proficient mismatch repair (pMMR) groups based on the immunohistochemistry results and the clinical feature data between the two groups were observed by statistical methods. RESULTS: The dMMR and pMMR groups had significant differences in histologic type, TNM stage, maximum tumor diameter, lymph node metastasis, differentiation grade, gross appearance, and vascular invasion. There were significant differences between the MLH1 groups in age, histologic type, TNM stage, lymph node metastasis, tumor location, and depth of invasion. The MSH2 groups were significantly different in age. The MSH6 groups had significant differences in age, histologic type, and TNM stage. There were significant differences between the PMS2 groups in lymph node metastasis and tumor location. CRC was dominated by MLH1 and PMS2 combined expression loss (41.77%). There was a positive correlation between MLH1 and MSH2 and between MSH6 and PMS2 as well. CONCLUSIONS: The proportion of mucinous adenocarcinoma, protruding type, and poor differentiation is relatively high in dMMR CRCs, but lymph node metastasis is rare. It is worth noting that the expression of MMR protein has different prognostic significance in different stages of CRC disease.


Assuntos
Neoplasias Colorretais , Reparo de Erro de Pareamento de DNA , Humanos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/genética , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Estadiamento de Neoplasias , Instabilidade de Microssatélites , Metástase Linfática , Adulto
9.
Kidney Blood Press Res ; 49(1): 430-442, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38797171

RESUMO

BACKGROUND: N-glycosylation is one of the most common posttranslational modifications in humans, and these alterations are associated with kidney diseases. METHODS: A novel technological approach, single-cell N-acetyllactosamine sequencing (scLacNAc-seq), was applied to simultaneously detect N-glycosylation expression and the transcriptome at single-cell resolution in three human kidney tissues from zero-time biopsy. Cell clusters, glycation abundance in each cell cluster, functional enrichment analysis, cell-cell crosstalk, and pseudotime analysis were applied. RESULTS: Using scLacNAc-seq, 24,247 cells and 22 cell clusters were identified, and N-glycan abundance in each cell was obtained. Transcriptome analysis revealed a close connection between capillary endothelial cells (CapECs) and parietal epithelial cells (PECs). PECs and CapECs communicate with each other through several pairs of ligand receptors (e.g., TGFB1-EGFR, GRN-EGFR, TIMP1-FGFR2, VEGFB-FLT1, ANGPT2-TEK, and GRN-TNFRSF1A). Finally, a regulatory network of cell-cell crosstalk between PECs and CapECs was constructed, which is involved in cell development. CONCLUSIONS: We here, for the first time, constructed the glycosylation profile of 22 cell clusters in the human kidney from zero-time biopsy. Moreover, cell-cell communication between PECs and CapECs through the ligand-receptor system may play a crucial regulatory role in cell proliferation.


Assuntos
Comunicação Celular , Células Endoteliais , Células Epiteliais , Rim , Humanos , Glicosilação , Células Endoteliais/metabolismo , Células Epiteliais/metabolismo , Rim/metabolismo , Rim/citologia , Análise de Célula Única
10.
BMC Anesthesiol ; 24(1): 12, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172695

RESUMO

BACKGROUND: The alteration of the prognostic nutritional index (PNI) or the utilization of distinct anesthesia strategies has been linked to the prognosis of various cancer types, but the existing evidence is limited and inconclusive, particularly for colorectal cancer (CRC). Our objective was to evaluate the association between PNI change and progression free survival (PFS) and overall survival (OS) in patients treated with CRC surgery after propofol-based or sevoflurane-based anesthesia. METHODS: We conducted a retrospective analysis of 414 patients with CRC who underwent surgical resection. Among them, 165 patients received propofol-based total intravenous anesthesia (TIVA-P), while 249 patients received sevoflurane-based inhalation anesthesia (IA-S). The PNI change (ΔPNI) was calculated by subtracting the pre-surgery PNI from the post-surgery PNI, and patients were categorized into high (≥ -2.25) and low (< -2.25) ΔPNI groups. Univariate and multivariate analyses were employed to evaluate the effects of the two anesthesia methods, ΔPNI, and their potential interaction on PFS and OS. RESULTS: The median duration of follow-up was 35.9 months (interquartile range: 18-60 months). The five-year OS rates were 63.0% in the TIVA-P group and 59.8% in the IA-S group (hazard ratio [HR]: 0.96; 95% confidence interval [CI]: 0.70-1.35; p = 0.864), while the five-year PFS rates were 55.8% and 51.0% (HR: 0.92; 95% CI: 0.68-1.26; p = 0.614), respectively. In comparison to patients in the low ΔPNI group, those in the high ΔPNI group exhibited a favorable association with both OS (HR: 0.57; 95% CI: 0.40-0.76; p < 0.001) and PFS (HR: 0.58; 95% CI: 0.43-0.79; p < 0.001). Stratified analysis based on ΔPNI revealed significant protective effects in the propofol-treated participants within the high ΔPNI group, whereas such effects were not observed in the low ΔPNI group, for both OS (p for interaction = 0.004) and PFS (p for interaction = 0.024). CONCLUSIONS: Our data revealed that among patients who underwent CRC surgery, those treated with TIVA-P exhibited superior survival outcomes compared to those who received IA-S, particularly among individuals with a high degree of PNI change.


Assuntos
Neoplasias Colorretais , Propofol , Humanos , Prognóstico , Sevoflurano , Avaliação Nutricional , Estudos Retrospectivos , Resultado do Tratamento , Anestesia por Inalação/métodos , Neoplasias Colorretais/cirurgia
11.
Biotechnol Lett ; 46(3): 373-383, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38493279

RESUMO

OBJECTIVE: Currently, there is lack of a consistent and highly enriched source for docosapentaenoic acid (n-3 DPA, C22:5), and this work report the isolation of microorganism that naturally produces n-3 DPA. RESULTS: In this work, we screened microorganisms in our culture collections with the goal to isolate a strain with high levels of n-3 DPA. We isolated a strain of Sphaeroforma arctica that produces up to 11% n-3 DPA in total fatty acid and has a high n-3 DPA to DHA/EPA ratio. The cell growth of the isolated strain was characterized using microscopy imaging and flow cytometer technologies to confirm the coenocytic pattern of cell divisions previously described in S. arctica. Our novel isolate of S. arctica grew more robustly and produced significantly more n-3 DPA compared to previously isolated and described strains indicating the uniqueness of the discovered strain. CONCLUSION: Overall, this work reports a first isolate n-3 DPA producing microorganism and establishes the foundation for future strain improvement and elucidation of the physiological function of this LC-PUFA for human nutrition and health.


Assuntos
Ácidos Graxos Insaturados , Ácidos Graxos Insaturados/metabolismo , Estramenópilas/metabolismo , Estramenópilas/isolamento & purificação
12.
Altern Ther Health Med ; 30(4): 113-117, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38330561

RESUMO

Objective: To examine the therapeutic effects of vitamin E combined with recombinant human epidermal growth factor on recurrent oral ulcers as well as on the levels of serum superoxide dismutase (SOD), interleukin-10 (IL-10), and tumor necrosis factor- (TNF-α), to provide evidence to facilitate medical management. Method: From June 2021 to May 2022, 84 patients with recurrent oral ulcers assessed and treated in our hospital were assigned to the control group and observation group with 42 cases in each group. Vitamin E was administered to the control group, while recombinant human epidermal growth factor and vitamin E were administered to the observation group. The clinical efficacy, serum SOD level, inflammatory factor level (IL-10, TNF-α), immune function index, clinical symptom improvement, pain disappearance time, healing time of ulcer surface, and adverse reactions were examined. Results: Clinical efficacy of the observation group (92.86%) was considerably greater than the control group (73.81%), (P < .05). Following treatment, the observation group had comparatively higher levels of serum SOD and significantly decreased TNF-α and IL-10 concentrations compared to the control group (P < .05). Similarly, post-treatment, the observation group had substantially higher CD3+, CD4+, and CD4+/CD8+ concentrations and lower CD8+ concentrations compared to the normal control (P < .05). In contrast to the control group, the observation group's pain degree score, ulcer diameter, duration for pain relief, and ulcer surface healing time duration were reduced substantially (P < .05). Notably, the incidence of adverse reactions was fairly similar in both groups (P > .05). Conclusion: Vitamin E combined with recombinant human epidermal growth factor has a significant clinical effect on recurrent oral ulcers, can achieve rapid improvement of symptoms in patients, and is relatively safe to be used as a clinical therapy.


Assuntos
Fator de Crescimento Epidérmico , Interleucina-10 , Úlceras Orais , Superóxido Dismutase , Fator de Necrose Tumoral alfa , Vitamina E , Humanos , Interleucina-10/sangue , Feminino , Masculino , Vitamina E/uso terapêutico , Vitamina E/farmacologia , Fator de Necrose Tumoral alfa/sangue , Superóxido Dismutase/sangue , Superóxido Dismutase/uso terapêutico , Pessoa de Meia-Idade , Úlceras Orais/tratamento farmacológico , Adulto , Fator de Crescimento Epidérmico/uso terapêutico , Fator de Crescimento Epidérmico/sangue , Proteínas Recombinantes/uso terapêutico , Proteínas Recombinantes/administração & dosagem , Idoso , Quimioterapia Combinada , Recidiva
13.
Phytochem Anal ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39258551

RESUMO

INTRODUCTION: Amomum fruit, also known as Sharen, serves as both a functional food and a traditional Chinese medicine with significant pharmacological activities. However, there are three botanical origins of Amomum fruit: Amomum villosum Lour. (AVL), Amomum villosum Lour. var. xanthioides T. L. (AVX), and Amomum longiligulare T. L. Wu (ALW). OBJECTIVE: Conducting a comprehensive chemical composition analysis of Amomum fruit from three botanical origins aims to identify potential differences in metabolic characteristics. METHODS: To annotate the metabolic characteristic ions of multi-origin Amomum fruit, we employed metabolomic techniques, including ultra-high-performance liquid chromatography (LC) coupled with linear ion trap-Orbitrap-tandem mass spectrometry (MS) and gas chromatography-MS, in conjunction with feature-based molecular networking technology. Additionally, chemometrics was utilized to examine the correlations between the various botanical origins. RESULTS: A total of 201 non-volatile and 151 volatile metabolites were annotated, and most of the proanthocyanidins and flavonoids were identified by feature-based molecular networking. Additionally, 61 non-volatile and 45 volatile feature ions were screened out for classification. Principal component analysis, orthogonal projection to latent structures discrimination analysis, and heat map analysis were employed to clearly distinguish the metabolite profiles of Amomum fruit from different origins. Hierarchical clustering analysis indicated that proanthocyanidins C1 and C2, as well as proanthocyanins oligomers, show significant differential expression between AVX and AVL, which could be the new quality markers for the classification. CONCLUSION: Classification of the botanical origin of Amomum fruit based on LC-MS characteristic ions proved to be more advantageous. This study introduces new strategies and technical support for the quality control of Amomum fruit and facilitates the identification of unknown compounds for future research.

14.
Int J Mol Sci ; 25(17)2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39273505

RESUMO

The TATA-box binding protein (TBP) and TBP-associated factors (TAFs) constitute the transcription factor IID (TFIID), a crucial component of RNA polymerase II, essential for transcription initiation and regulation. Several TFIID subunits are shared with the Spt-Ada-Gcn5-acetyltransferase (SAGA) coactivator complex. Recent research has revealed the roles of TBP and TAFs in organogenesis and stress adaptation. In this study, we identified 1 TBP and 21 putative TAFs in the mungbean genome, among which VrTAF5, VrTAF6, VrTAF8, VrTAF9, VrTAF14, and VrTAF15 have paralogous genes. Their potential involvement in abiotic stress responses was also investigated here, including high salinity, water deficit, heat, and cold. The findings indicated that distinct genes exerted predominant influences in the response to different abiotic stresses through potentially unique mechanisms. Specifically, under salt stress, VrTBP, VrTAF2, and VrTAF15-1 were strongly induced, while VrTAF10, VrTAF11, and VrTAF13 acted as negative regulators. In the case of water-deficit stress, it was likely that VrTAF1, VrTAF2, VrTAF5-2, VrTAF9, and VrTAF15-1 were primarily involved. Additionally, in response to changes in ambient temperature, it was possible that genes such as VrTAF5-1, VrTAF6-1, VrTAF9-2, VrTAF10, VrTAF13, VrTAF14b-2, and VrTAF15-1 might play a dominant role. This comprehensive exploration of VrTBP and VrTAFs can offer a new perspective on understanding plant stress responses and provide valuable insights into breeding improvement.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Estresse Fisiológico , Vigna , Vigna/genética , Vigna/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Proteína de Ligação a TATA-Box/metabolismo , Proteína de Ligação a TATA-Box/genética , Fatores Associados à Proteína de Ligação a TATA/metabolismo , Fatores Associados à Proteína de Ligação a TATA/genética , Filogenia
15.
J Environ Manage ; 350: 119652, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38016235

RESUMO

Renewable energy (RE) plays a crucial role in global energy transformation, and a thorough study of the potential impact of RE on regional carbon emissions is of great significance. This is particularly relevant to China, which needs to clarify its path to carbon reduction. Using the sample data of 30 provinces in China from 2000 to 2021, this paper uses the Granger causality test to verify the causal relationship between carbon emission intensity (CEI) and other factors. It builds a mediation effect model on this basis to explore the direct impact effect and indirect transmission path of renewable energy utilization (REU) on CEI. The results show that REU has a one-way causal relationship with CEI. REU can directly and indirectly reduce CEI by improving social wealth and changing the direction of energy investment. In addition, REU indirectly increases CEI through the transmission paths of investment in the energy industry - social affluence and industrial level-social affluence. The CEI is indirectly reduced through the conduction paths of (social affluence-Urbanization rate), (Investment in the energy industry-Urbanization rate), (Industrial level-Urbanization rate), and (Industrial level-Investment in the energy industry). These conclusions will assist policymakers in exploring targeted pathways for low-carbon power development, providing a reference for strategic and sustainable carbon reduction policies.


Assuntos
Dióxido de Carbono , Carbono , Carbono/análise , Dióxido de Carbono/análise , Urbanização , Energia Renovável , China , Desenvolvimento Econômico
16.
Molecules ; 29(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38398519

RESUMO

To enhance the bioavailability and antihypertensive effect of the anti-depressant drug citalopram hydrobromide (CTH) we developed a sustained-release transdermal delivery system containing CTH. A transdermal diffusion meter was first used to determine the optimal formulation of the CTH transdermal drug delivery system (TDDS). Then, based on the determined formulation, a sustained-release patch was prepared; its physical characteristics, including quality, stickiness, and appearance, were evaluated, and its pharmacokinetics and irritation to the skin were evaluated by applying it to rabbits and rats. The optimal formulation of the CTH TDDS was 49.2% hydroxypropyl methyl cellulose K100M, 32.8% polyvinylpyrrolidone K30, 16% oleic acid-azone, and 2% polyacrylic acid resin II. The system continuously released an effective dose of CTH for 24 h and significantly enhanced its bioavailability, with a higher area under the curve, good stability, and no skin irritation. The developed CTH TDDS possessed a sustained-release effect and good characteristics and pharmacokinetics; therefore, it has the potential for clinical application as an antidepressant.


Assuntos
Citalopram , Absorção Cutânea , Ratos , Coelhos , Animais , Citalopram/farmacologia , Citalopram/metabolismo , Preparações de Ação Retardada/farmacologia , Administração Cutânea , Pele , Sistemas de Liberação de Medicamentos , Adesivo Transdérmico
17.
Metab Eng ; 76: 18-28, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36626963

RESUMO

Plants produce many high-value oleochemical molecules. While oil-crop agriculture is performed at industrial scales, suitable land is not available to meet global oleochemical demand. Worse, establishing new oil-crop farms often comes with the environmental cost of tropical deforestation. The field of metabolic engineering offers tools to transplant oleochemical metabolism into tractable hosts while simultaneously providing access to molecules produced by non-agricultural plants. Here, we evaluate strategies for rewiring metabolism in the oleaginous yeast Yarrowia lipolytica to synthesize a foreign lipid, 3-acetyl-1,2-diacyl-sn-glycerol (acTAG). Oils made up of acTAG have a reduced viscosity and melting point relative to traditional triacylglycerol oils making them attractive as low-grade diesels, lubricants, and emulsifiers. This manuscript describes a metabolic engineering study that established acTAG production at g/L scale, exploration of the impact of lipid bodies on acTAG titer, and a techno-economic analysis that establishes the performance benchmarks required for microbial acTAG production to be economically feasible.


Assuntos
Yarrowia , Triglicerídeos/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Engenharia Metabólica , Metabolismo dos Lipídeos , Óleos/metabolismo
18.
Inorg Chem ; 62(13): 5262-5269, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36947415

RESUMO

Porous carbon-supported atomically ordered intermetallic compounds (IMCs) are promising electrocatalysts in boosting oxygen reduction reaction (ORR) for fuel cell applications. However, the formation mechanism of IMC structures under high temperatures is poorly understood, which hampers the synthesis of highly ordered IMC catalysts with promoted ORR performance. Here, we employ high-temperature X-ray diffraction and energy-dispersive spectroscopic elemental mapping techniques to study the formation process of IMCs, by taking PtCo for example, in an industry-relevant impregnation synthesis. We find that high-temperature annealing is crucial in promoting the formation of alloy particles with a stoichiometric Co/Pt ratio, which in turn is the precondition for transforming the disordered alloys to ordered intermetallic structures at a relatively low temperature. Based on the findings, we accordingly synthesize highly ordered L10-type PtCo catalysts with a remarkable ORR performance in fuel cells.

19.
Org Biomol Chem ; 21(7): 1450-1456, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36651476

RESUMO

The Ru(dppbsa)-catalyzed reductive amination of ketones with nitroarenes and nitriles using H2 as the environmentally benign hydrogen surrogate is developed in this study. Cross-experiments demonstrated that both reactions are initiated by the reduction of nitroarenes or nitriles to the corresponding amines, followed by condensation with ketones to give imines and thereafter hydrogenation. However, the route to the formation of an amino-ligated Ru complex during the reduction of nitroarenes or nitriles, followed by in situ nucleophilic C-N coupling, cannot be completely excluded. This newly developed versatile method features good functional group tolerance, which provides a novel design platform for homogeneous catalysts in constructing motifs of secondary amines.

20.
Nanotechnology ; 34(23)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36848663

RESUMO

Developing new membranes with both high selectivity and permeability is critical in membrane science since conventional membranes are often limited by the trade-off between selectivity and permeability. In recent years, the emergence of advanced materials with accurate structures at atomic or molecular scale, such as metal organic framework, covalent organic framework, graphene, has accelerated the development of membranes, which benefits the precision of membrane structures. In this review, current state-of-the-art membranes are first reviewed and classified into three different types according to the structures of their building blocks, including laminar structured membranes, framework structured membranes and channel structured membranes, followed by the performance and applications for representative separations (liquid separation and gas separation) of these precisely designed membranes. Last, the challenges and opportunities of these advanced membranes are also discussed.

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