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1.
Clin Infect Dis ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39158989

RESUMO

PURPOSE: To identify weather variables associated with pathogens contributing to infectious conjunctivitis globally. METHODS: Sample collection and pathogen identification from patients with acute infectious conjunctivitis was performed from 2017 to 2023. We linked pathogens identified from 13 sites across 8 countries with publicly available weather data by geographic coordinates. Mixed effects logistic regression analysis was performed to estimate the associations between temperature, precipitation, and relative humidity exposures, and the prevalence of infection types (RNA virus, DNA virus, bacteria, and fungus). RESULTS: 498 cases from the United States, India, Nepal, Thailand, Burkina Faso, Niger, Vietnam, and Israel were included in the analysis. 8-day average precipitation (mm) was associated with increased odds of RNA virus infection (odds ratio (OR)=1.47, 95% confidence interval (CI): 1.12 to 1.93, P=0.01) and decreased odds of DNA infection (OR=0.62, 95% CI: 0.46 to 0.82, P<0.001). Relative humidity (%) was associated with increased odds of RNA virus infections (OR=2.64, 95% CI: 1.51 to 4.61, P<0.001), and fungal infections (OR=2.35, 95% CI: 1.19 to 4.66, P=0.01), but decreased odds of DNA virus (OR=0.58, 95%CI: 0.37 to 0.90, P=0.02) and bacterial infections (OR=0.42, 95% CI: 0.25 to 0.71, P<0.001). Temperature (°C) was not associated with ocular infections for any pathogen type. CONCLUSIONS: This study suggests that weather factors affect pathogens differently. Particularly, humidity and precipitation were predictors for pathogens contributing to conjunctivitis worldwide. Additional work is needed to clarify the effects of shifts in weather and environmental factors on ocular infectious diseases.

2.
Eur J Nucl Med Mol Imaging ; 51(2): 581-589, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37819451

RESUMO

PURPOSE: The objective of this study was to evaluate the diagnostic performance and image quality of total-body positron emission tomography/computed tomography (PET/CT) imaging using a half-dose of [68 Ga]Ga-prostate specific membrane antigen ([68 Ga]Ga-PSMA) radiotracer, compared to conventional short axial field-of-view PET/CT imaging using a full dose of [68 Ga]Ga-PSMA. METHODS: This retrospective study enrolled 52 patients with biochemical recurrent (BCR) prostate cancer after radical prostatectomy who underwent total-body PET/CT with a half-dose (0.9-1.1 MBq/kg) of [68 Ga]Ga-PSMA. These patients were matched by baseline characteristics to another 52 BCR patients after prostatectomy who underwent conventional PET/CT with a full dose (1.8-2.2 MBq/kg) of [68 Ga]Ga-PSMA. The half-dose group was further divided into 5-min (G5) and 2-min (G2) acquisition subgroups. Image quality was assessed through subjective analysis using a 5-point scale and objective measurements of standard uptake value maximum (SUVmax), standard uptake value mean (SUVmean), background variation (BV) of the liver, blood pool, and parotid glands. Additionally, SUVmax and tumor-to-background ratio (TBR) were calculated for lesions. RESULTS: No significant difference in subjective image quality was found between the G2 and full-dose groups (p > 0.05). PET/CT image quality was significantly higher for the G5 versus G2 (p < 0.001) and full-dose groups (p < 0.001). TBR did not differ between the G2 and full-dose groups (4.23 ± 5.21 vs 4.22 ± 3.97, p = 0.99). Liver BV was significantly lower for G2 versus full-dose groups (0.16 ± 0.03 vs 0.20 ± 0.05, p < 0.001). CONCLUSIONS: Total-body PET/CT with a half-dose [68 Ga]Ga-PSMA yields image quality superior or comparable to that of conventional PET/CT. The utilization of total-body [68 Ga]Ga-PSMA PET/CT meets the diagnostic demands of BCR patients, particularly those who exhibit reduced tolerance to prolonged horizontal positioning and scan durations, while simultaneously reducing radiation exposure for the subjects.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Masculino , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Retrospectivos , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Neoplasias da Próstata/patologia , Radioisótopos de Gálio , Ácido Edético
3.
Eur J Nucl Med Mol Imaging ; 51(6): 1753-1762, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38212531

RESUMO

PURPOSE: This is a first-in-human study to evaluate the radiation dosimetry of a new prostate-specific membrane antigen (PSMA)-targeted radiopharmaceutical, [18F]AlF-P16-093, and also initial investigation of its ability to detect PSMA-positive tumors using PET scans in a cohort of prostate cancer (PCa) patients. METHODS: The [18F]AlF-P16-093 was automatically synthesized with a GE TRACERlab. A total of 23 patients with histopathologically proven PCa were prospectively enrolled. Dosimetry and biodistribution study investigations were carried out on a subset of six (6) PCa patients, involving multiple time-point scanning. The mean absorbed doses were estimated with PMOD and OLINDA software. RESULTS: [18F]AlF-P16-093 was successfully synthesized, and radiochemical purity was > 95%, and average labeling yield was 36.5 ± 8.3% (decay correction, n = 12). The highest tracer uptake was observed in the kidneys, spleen, and liver, contributing to an effective dose of 16.8 ± 1.3 µSv/MBq, which was ~ 30% lower than that of [68Ga]Ga-P16-093. All subjects tolerated the PET examination well, and no reportable side-effects were observed. The PSMA-positive tumors displayed rapid uptake, and they were all detectable within 10 min, and no additional lesions were observed in the following multi-time points scanning. Each patient had at least one detectable tumor lesion, and a total of 356 tumor lesions were observed, including intraprostatic, lymph node metastases, bone metastases, and other soft tissue metastases. CONCLUSIONS: We report herein a streamlined method for high yield synthesis of [18F]AlF-P16-093. Preliminary study in PCa patients has demonstrated its safety and acceptable radiation dosimetry. The initial diagnostic study indicated that [18F]AlF-P16-093 PET/CT is efficacious and potentially useful for a widespread application in the diagnosis of PCa patients.


Assuntos
Antígenos de Superfície , Glutamato Carboxipeptidase II , Neoplasias da Próstata , Radiometria , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Idoso , Glutamato Carboxipeptidase II/metabolismo , Pessoa de Meia-Idade , Antígenos de Superfície/metabolismo , Distribuição Tecidual , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/química , Radioisótopos de Flúor/química , Idoso de 80 Anos ou mais , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
4.
J Org Chem ; 89(11): 7630-7643, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38738853

RESUMO

Atropoisomeric chemotypes of diaryl ethers-related scaffolds are prevalent in naturally active compounds. Nevertheless, there remains considerable research to be carried out on the catalytic asymmetric synthesis of these axially chiral molecules. In this instance, we disclose an N-heterocyclic carbene (NHC)-catalyzed synthesis of axially chiral diaryl ethers via atroposelective esterification of dialdehyde-containing diaryl ethers. NHC desymmetrization produces axially chiral diaryl ether atropisomers with high yields and enantioselectivities in moderate circumstances. Chiral diaryl ether compounds may be precursors for highly functionalized diaryl ethers with bioactivity and chiral ligands for asymmetric catalysis.

5.
Bioorg Chem ; 142: 106932, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37913586

RESUMO

The incidence of infections caused by drug-resistant bacteria has been one of the most serious health threats in the past and is substantially increasing in an alarming rate. Therefore, the development of new antimicrobial agents to combat bacterial resistance effectively is urgent. This study focused on the design and synthesis of 40 novel tetrahydrobenzothiophene amide/sulfonamide derivatives and their antibacterial activities were evaluated. Compounds 2p, 6p, and 6 s exhibited significant inhibitory effects on the growth of bacteria. To assess their safety, the cytotoxicity of the compounds was assessed using human normal liver cells, revealing that compound 6p has lower cytotoxicity. A mouse wound healing experiment demonstrated that compound 6p effectively improved wound infection induced by trauma and accelerated the healing process. Compound 6p holds promise as a potential therapeutic agent for combating bacterial infections.


Assuntos
Antibacterianos , Anti-Infecciosos , Humanos , Animais , Camundongos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Bactérias
6.
Drug Dev Res ; 85(2): e22164, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38411296

RESUMO

Compared to traditional small molecule and antibody drugs, RNA-based drugs offer a simple design, short research and development cycles, high specificity, broad treatment fields, and long-term efficacy. As a result, RNA-based drugs are extensively used to treat genetic diseases, tumors, viral infections, and other illnesses, suggesting that they have the potential to become the third-largest drug class after small molecule and antibody drugs. Currently, more than 10 small nucleic acid drugs have gained regulatory approval. The commercialization successes of small nucleic acid drugs will stimulate the development of RNA-based drugs. Small nucleic acid drugs primarily target liver diseases, metabolic diseases, genetic diseases, and tumors, and there is also significant potential for expanding indications in the future. This review provides a brief overview of the advantages and development of small nucleic acid-based therapeutics and shows a focus on platform technologies such as chemical modifications and delivery systems that have enabled the clinical translation of small nucleic acid-based therapeutics. Additionally, we summarize the latest clinical progress in small nucleic acid-based therapeutics for the treatment of various diseases, including rare diseases, liver diseases, metabolic diseases, and tumors. Finally, we highlight the future prospects for this promising treatment approach.


Assuntos
Doenças Metabólicas , Neoplasias , Ácidos Nucleicos , Humanos , Ácidos Nucleicos/uso terapêutico , Ácidos Nucleicos/química , RNA Interferente Pequeno , Preparações Farmacêuticas , Neoplasias/tratamento farmacológico , Neoplasias/genética , Doenças Metabólicas/tratamento farmacológico
7.
Molecules ; 29(15)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39124912

RESUMO

It is important to develop effective strategies for enhancing the removal capacity of aromatic volatile organic compounds (VOCs) by modifying conventional porous adsorbents. In this study, a novel HZSM-5 zeolite-supported sulfonic acid (ZSM-OSO3H) was prepared through ClSO3H modification in dichloromethane and employed for the elimination of gaseous o-xylene. The ClSO3H modification enables the bonding of -OSO3H groups onto the HZSM-5 support, achieving a loading of 8.25 mmol·g-1 and leading to a degradation in both crystallinity and textural structure. Within an active temperature range of 110-145 °C, ZSM-OSO3H can efficiently remove o-xylene through a novel reactive adsorption mechanism, exhibiting a removal rate exceeding 98% and reaching a maximum breakthrough adsorption capacity of 264.7 mg. The adsorbed o-xylene derivative is identified as 3,4-dimethylbenzenesulfonic acid. ZSM-OSO3H demonstrates superior adsorption performance for o-xylene along with excellent recyclability. These findings suggest that ClSO3H sulfonation offers a promising approach for modifying various types of zeolites to enhance both the elimination and resource conversion of aromatic VOCs.

8.
J Cell Physiol ; 238(8): 1693-1715, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37334436

RESUMO

This review summarizes the implications of the primary tumor suppressor protein phosphatase and tensin homolog (PTEN) in aggressive cancer development. PTEN interacts with other cellular proteins or factors suggesting the existence of an intricate molecular network that regulates their oncogenic function. Accumulating evidence has shown that PTEN exists and plays a role in the cytoplasmic organelles and in the nucleus. PTEN blocks phosphoinositide 3-kinases (PI3K)-protein kinase B-mammalian target of rapamycin signaling pathway by dephosphorylating phosphatidylinositol (PI)-3,4,5-triphosphate to PI-4,5-bisphosphate thus counteracting PI3K function. Studies have shown that PTEN expression is tightly regulated at transcriptional, posttranscriptional, and posttranslational levels (including protein-protein interactions and posttranslational modifications). Despite recent advances in PTEN research, the regulation and function of the PTEN gene remain largely unknown. How mutation or loss of specific exons in the PTEN gene occurs and involves in cancer development is not clear. This review illustrates the regulatory mechanisms of PTEN expression and discusses how PTEN participates in tumor development and/or suppression. Future prospects for the clinical applications are also highlighted.


Assuntos
Biomarcadores Tumorais , Neoplasias , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genética , Neoplasias/patologia , Processamento de Proteína Pós-Traducional , Fosfatidilinositol 3-Quinases/metabolismo
9.
Funct Integr Genomics ; 23(2): 186, 2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37243790

RESUMO

Osteoporosis is a common disease, especially among the elderly. This study aimed to comprehensively examine the roles of immune microenvironment in osteoporosis pathogenesis. Expression profiles of GSE35959, GSE7158, and GSE13850 datasets were used to analyze differential expression and identify hub genes related to immune features. Based on the single-cell RNA sequencing (scRNA-seq) data of an osteoporosis patient, different cell types were classified and the relation between immune environment and osteoporosis was explored. Twelve hub genes significantly associated with immune features were selected and 11 subgroups were defined using scRNA-seq data. The expression of two hub genes (CDKN1A and TEFM) was greatly altered during the transformation from mesenchymal stem cells (MSCs) to osteoblasts. Chemokines and chemokine receptors were differentially enriched in different cell types. CXCL12 was high-expressed in MSCs. This study emphasized that immune microenvironment played a critical role in the pathogenesis of osteoporosis. Chemokines and chemokine receptors can modify cell development and affect the interactions among different cell types, leading to unbalanced bone remodeling.


Assuntos
Osteoporose , Humanos , Idoso , Células Cultivadas , Osteoporose/genética , Quimiocinas/genética , Receptores de Quimiocinas/genética , Análise de Sequência de RNA
10.
Small ; 19(17): e2205739, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36592424

RESUMO

Ischemic stroke and systemic cancer are two of the leading causes of mortality. Hypoxia is a central pathophysiological component in ischemic stroke and cancer, representing a joint medical function. This function includes angiogenesis regulation. Vascular remodeling coupled with axonal outgrowth following cerebral ischemia is critical in improving poststroke neurological functional recovery. Antiangiogenic strategies can inhibit cancer vascularization and play a vital role in impeding cancer growth, invasion, and metastasis. Although there are significant differences in the cause of angiogenesis across both pathophysiological conditions, emerging evidence states that common signaling structures, such as extracellular vesicles (EVs) and noncoding RNAs (ncRNAs), are involved in this context. EVs, heterogeneous membrane vesicles encapsulating proteomic genetic information from parental cells, act as multifunctional regulators of intercellular communication. Among the multifaceted roles in modulating biological responses, exhaustive evidence shows that ncRNAs are selectively sorted into EVs, modulating common specific aspects of cancer development and stroke prognosis, namely, angiogenesis. This review will discuss recent advancements in the EV-facilitated/inhibited progression of specific elements of angiogenesis with a particular concern about ncRNAs within these vesicles. The review is concluded by underlining the clinical opportunities of EV-derived ncRNAs as diagnostic, prognostic, and therapeutic agents.


Assuntos
Vesículas Extracelulares , AVC Isquêmico , Neoplasias , Humanos , Proteômica , Neoplasias/tratamento farmacológico , RNA não Traduzido/genética
11.
Opt Lett ; 48(2): 239-242, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36638427

RESUMO

We present, to our knowledge, the first experimental demonstration of two on-chip gratings for perfectly vertical coupling at wavelengths of 3350 nm and 3550 nm, respectively. An anti-backreflection unit containing a fully etched trench and a subwavelength pillar is introduced in each grating period, together with a binary-approximated blazed unit, interleaving fully and shallow-etched slots in 500-nm thick silicon film. Both gratings show a strong ability to eliminate backreflection and provide predicted directionality of around 80%. The physical theoretical analysis is applied during further apodization for mitigating the computation of the optimization algorithm, improving the efficiency and optimization reliability, and increasing the fabrication robustness. The measured coupling efficiencies (CEs) of the gratings are -5.58 dB and -4.34 dB at wavelengths of 3350 nm and 3550 nm, with a 3-dB bandwidth of at least 87 nm and 210 nm, respectively.

12.
Cell Commun Signal ; 21(1): 366, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129877

RESUMO

BACKGROUND: Macrophages and neutrophils are rapidly recruited around Schistosome eggs to form granulomas. Extracellular traps (ETs) of macrophages and neutrophils are part of the pathogen clearance armamentarium of leukocytes. Schistosome eggs possess the ability to resist attack by the host's immune cells and survive by employing various immune evasion mechanisms, including the release of extracellular vesicles (EVs). However, the specific mechanisms by which Schistosome egg-derived EVs (E-EVs) evade the immune response and resist attack from macrophage and neutrophil ETs remain poorly understood. In this study, we aimed to investigate the association between E-EVs and macrophage/neutrophil ETs. METHODS: EVs were isolated from the culture supernatant of S. japonicum eggs and treated macrophages and neutrophils with E-EVs and Sja-miR-71a. The formation of ETs was then observed. Additionally, we infected mice with S. japonicum, administered HBAAV2/9-Sja-miR-71a, and the formation of macrophage ETs (METs) and neutrophil ETs (NETs) in the livers was measured. Sema4D-knockout mice, RNA sequencing, and trans-well assay were used to clarify Sja-miR-71a in E-EVs inhibits METs and NETs formation via the Sema4D/ PPAR-γ/ IL-10 axis. RESULTS: Our findings revealed that E-EVs were internalized by macrophages and neutrophils, leading to the inhibition of METs and NETs formation. The highly expressed Sja-miR-71a in E-EVs targeted Sema4D, resulting in the up-regulation of IL-10 and subsequent inhibition of METs and NETs formation. Sema4D knockout up-regulated IL-10 expression and inhibited the formation of METs and NETs. Furthermore, we further demonstrated that Sja-miR-71a inhibits METs and NETs formation via the Sema4D/ PPAR-γ/ IL-10 axis. CONCLUSIONS: In summary, our findings provide new insights into the immune evasion abilities of Schistosome eggs by demonstrating their ability to inhibit the formation of METs and NETs through the secretion of EVs. This study enhances our understanding of the host-pathogen interaction and may have implications for the development of novel therapeutic approaches. Video Abstract.


Assuntos
Armadilhas Extracelulares , Vesículas Extracelulares , MicroRNAs , Schistosoma japonicum , Camundongos , Animais , Schistosoma japonicum/genética , Interleucina-10 , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Neutrófilos , Vesículas Extracelulares/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Macrófagos
13.
Protein Expr Purif ; 212: 106359, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37625736

RESUMO

Sesquiterpene synthases (TPS) determine the structural diversity of terpenoids, which are species specific. In this study, we report a TPS from Fischerella thermalis (named as FtTPS), recombinantly expressed as a soluble protein in Escherichia coli BL21(DE3) strain. The FtTPS protein could catalyze the conversion of farnesyl pyrophosphate (FPP) to sativene, a kind of tricyclic sesquiterpene. The optimal pH and temperature of FtTPS were 7.5 and 30 °C, respectively. The KM and Vmax values of FtTPS for FPP were 1.846 µM and 0.372 µM/min, respectively. By constructing an engineered E. coli strain carrying the FtTPS and the heterologous mevalonate (MVA) pathway genes, sativene could be detected and its yield reached 24 mg/L after 96 h cultivation. The highest yield of sativene was obtained when E.coli BL21 Star was used as the host with SBMSN medium. These results exhibited the biosynthesis of sativene for the first time.


Assuntos
Escherichia coli , Sesquiterpenos , Escherichia coli/genética
14.
Pharmacol Res ; 195: 106886, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37591326

RESUMO

Liver fibrosis can occur in many chronic liver diseases, and no effective treatments are available due to the poorly characterized molecular pathogenesis. Semaphorin 4D (Sema4D) has immune functions and serves important roles in T cell priming. Here, we found that Sema4D was highly expressed in fibrotic liver, and the expression of Sema4D increased with hepatic stellate cells (HSCs) activation. Knockout of Sema4D alleviated liver fibrosis. Mechanistically, knockout of Sema4D alleviated liver fibrosis by suppressing the expression of AOX1 in retinol metabolism. Further investigation demonstrated that retinoic acid receptor α (RARA), an important nuclear receptor of retinoic acid, was reduced by Sema4D knockout during liver fibrogenesis. Sema4D knockout-mediated suppression of liver fibrosis was partly mediated by regulating the balance of Th1, Th2, Th17, and T-bet+Treg cells via inhibiting AOX1/RARA. Thus, targeting Sema4D may hold promise as a potential therapeutic approach for treating liver fibrosis.


Assuntos
Cirrose Hepática , Semaforinas , Animais , Humanos , Masculino , Camundongos , Aldeído Oxidase , Antígenos CD , Cirrose Hepática/genética , Camundongos Knockout , Semaforinas/genética
15.
J Org Chem ; 88(11): 6633-6644, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37133412

RESUMO

Pyranones have raised great concerns owing to their considerable applications in a variety of sectors. However, the development of direct asymmetric allylation of 4-hydroxypyran-2-ones is still restricted. Herein, we present an effective iridium-catalyzed asymmetric functionalization technique for the synthesis of 4-hydroxypyran-2-one derivatives over direct and efficient catalytic asymmetric Friedel-Crafts-type allylation by using allyl alcohols. The allylation products could be obtained with good to high yields (up to 96%) and excellent enantioselectivities (>99% ee). Therefore, the disclosed technique provides a new asymmetric synthetic strategy to explore pyranone derivatives in depth, thus providing an interesting approach for global application and further utilization in organic synthesis and pharmaceutical chemistry.

16.
Angew Chem Int Ed Engl ; 62(7): e202216534, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36536515

RESUMO

Diaryl ethers are widespread in biologically active compounds, ligands and catalysts. It is known that the diaryl ether skeleton may exhibit atropisomerism when both aryl rings are unsymmetrically substituted with bulky groups. Despite recent advances, only very few catalytic asymmetric methods have been developed to construct such axially chiral compounds. We describe herein a dynamic kinetic resolution approach to axially chiral diaryl ethers via a Brønsted acid catalyzed atroposelective transfer hydrogenation (ATH) reaction of dicarbaldehydes with anilines. The desired diaryl ethers could be obtained in moderate to good chemical yields (up to 79 %) and high enantioselectivities (up to 95 % ee) under standard reaction conditions. Such structural motifs are interesting precursors for further transformations and may have potential applications in the synthesis of chiral ligands or catalysts.

17.
Angew Chem Int Ed Engl ; 62(40): e202308091, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37340794

RESUMO

The coordination structure determines the electrocatalytic performances of single atom catalysts (SACs), while it remains a challenge to precisely regulate their spatial location and coordination environment. Herein, we report a universal sub-nanoreactor strategy for synthesis of yolk-shell MoS2 supported single atom electrocatalysts with dual-anchored microenvironment of vacancy-enriched MoS2 and intercalation carbon toward robust hydrogen-evolution reaction. Theoretical calculations reveal that the "E-Lock" and "E-Channel" are conducive to stabilize and activate metal single atoms. A group of SACs is subsequently produced with the assistance of sulfur vacancy and intercalation carbon in the yolk-shell sub-nanoreactor. The optimized C-Co-MoS2 yields the lowest overpotential (η10 =17 mV) compared with previously reported MoS2 -based electrocatalysts to date, and also affords a 5-9 fold improvement in activity even comparing with those as-prepared single-anchored analogues. Theoretical results and in situ characterizations unveil its active center and durability. This work provides a universal pathway to design efficient catalysts for electro-refinery.

18.
Molecules ; 27(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36364310

RESUMO

Chemical modification of old drugs is an important way to obtain new ones, and it has been widely used in developing new aminoglycoside antibiotics. However, many of the previous modifying strategies seem arbitrary for their lack of support from structural biological detail. In this paper, based on the structural information of aminoglycoside and its drug target, we firstly analyzed the reason that some 2'-N-acetylated products of aminoglycosides caused by aminoglycoside-modifying enzyme AAC(2') can partially retain activity, and then we designed, synthesized, and evaluated a series of 2'-modified kanamycin A derivatives. Bioassay results showed our modifying strategy was feasible. Our study provided valuable structure-activity relationship information, which would help researchers to develop new aminoglycoside antibiotics more effectively.


Assuntos
Aminoglicosídeos , Canamicina , Canamicina/farmacologia , Canamicina/química , Aminoglicosídeos/química , Antibacterianos/química , Relação Estrutura-Atividade , Bioensaio , Acetiltransferases
19.
Molecules ; 27(16)2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36014361

RESUMO

Efficient removal of cumene from gaseous streams and recovery of its derivatives was accomplished using a MCM-41-supported sulfuric acid (SSA/MCM-41) adsorbent. The results indicated that the removal performance of the SSA/MCM-41 for cumene was significantly influenced by the process conditions such as bed temperature, inlet concentration, bed height, and flow rate. The dose-response model could perfectly describe the collected breakthrough adsorption data. The SSA/MCM-41 adsorbent exhibited a reactive temperature region of 120-170 °C, in which the cumene removal ratios (Xc) were greater than 97%. Rising the bed height or reducing the flow rate enhanced the theoretical adsorption performance metrics, such as theoretical breakthrough time (tB,th) and theoretical breakthrough adsorption capacity (QB,th), whereas increasing the inlet concentration resulted in tB,th shortening and QB,th rising. As demonstrated in this paper, the highest tB,th and QB,th were 69.60 min and 324.50 mg g-1, respectively. Meanwhile, the spent SSA/MCM-41 could be desorbed and regenerated for cyclic reuse. Moreover, two recoverable adsorbed products, 4-isopropylbenzenesulfonic acid and 4, 4'-sulfonyl bis(isopropyl-benzene), were successfully separated and identified using FTIR and 1H/13C NMR characterization. Accordingly, the relevance of a reactive adsorption mechanism was confirmed. This study suggests that the SSA/MCM-41 has remarkable potential for application as an adsorbent for the resource treatment of cumene pollutants.


Assuntos
Gases , Poluentes Químicos da Água , Adsorção , Derivados de Benzeno , Dióxido de Silício , Ácidos Sulfúricos , Poluentes Químicos da Água/química
20.
Opt Express ; 29(4): 5397-5406, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33726076

RESUMO

Lithium niobate (LN) devices have been widely used in optical communication and nonlinear optics due to its attractive optical properties. The emergence of the thin-film lithium niobate on insulator (LNOI) improves performances of LN-based devices greatly. However, a high-efficient fiber-chip optical coupler is still necessary for the LNOI-based devices for practical applications. In this paper, we demonstrate a highly efficient and polarization-independent edge coupler based on LNOI. The coupler, fabricated by a standard semiconductor process, shows a low fiber-chip coupling loss of 0.54 dB/0.59 dB per facet at 1550 nm for TE/TM light, respectively, when coupled with an ultra-high numerical aperture fiber (UHNAF) of which the mode field diameter is about 3.2 µm. The coupling loss is lower than 1dB/facet for both TE and TM light in the wavelength range of 1527 nm to 1630 nm. A relatively large tolerance for optical misalignment is also proved, due to the coupler's large mode spot size up to 3.2 µm. The coupler shows a promising stability in high optical power and temperature variation.

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