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1.
Eur J Nucl Med Mol Imaging ; 51(2): 581-589, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37819451

RESUMEN

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.


Asunto(s)
Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata , Masculino , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Estudios Retrospectivos , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Neoplasias de la Próstata/patología , Radioisótopos de Galio , Ácido Edético
2.
Eur J Nucl Med Mol Imaging ; 51(6): 1753-1762, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38212531

RESUMEN

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.


Asunto(s)
Antígenos de Superficie , Glutamato Carboxipeptidasa II , Neoplasias de la Próstata , Radiometría , Humanos , Masculino , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Anciano , Glutamato Carboxipeptidasa II/metabolismo , Persona de Mediana Edad , Antígenos de Superficie/metabolismo , Distribución Tisular , Radiofármacos/farmacocinética , Radiofármacos/química , Radioisótopos de Flúor/química , Anciano de 80 o más Años , Tomografía Computarizada por Tomografía de Emisión de Positrones
3.
J Org Chem ; 89(11): 7630-7643, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38738853

RESUMEN

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.

4.
Bioorg Chem ; 142: 106932, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37913586

RESUMEN

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.


Asunto(s)
Antibacterianos , Antiinfecciosos , Humanos , Animales , Ratones , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Bacterias
5.
Drug Dev Res ; 85(2): e22164, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38411296

RESUMEN

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.


Asunto(s)
Enfermedades Metabólicas , Neoplasias , Ácidos Nucleicos , Humanos , Ácidos Nucleicos/uso terapéutico , Ácidos Nucleicos/química , ARN Interferente Pequeño , Preparaciones Farmacéuticas , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Enfermedades Metabólicas/tratamiento farmacológico
6.
J Cell Physiol ; 238(8): 1693-1715, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37334436

RESUMEN

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.


Asunto(s)
Biomarcadores de Tumor , Neoplasias , Humanos , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/genética , Neoplasias/patología , Procesamiento Proteico-Postraduccional , Fosfatidilinositol 3-Quinasas/metabolismo
7.
Funct Integr Genomics ; 23(2): 186, 2023 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-37243790

RESUMEN

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.


Asunto(s)
Osteoporosis , Humanos , Anciano , Células Cultivadas , Osteoporosis/genética , Quimiocinas/genética , Receptores de Quimiocina/genética , Análisis de Secuencia de ARN
8.
Small ; 19(17): e2205739, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36592424

RESUMEN

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.


Asunto(s)
Vesículas Extracelulares , Accidente Cerebrovascular Isquémico , Neoplasias , Humanos , Proteómica , Neoplasias/tratamiento farmacológico , ARN no Traducido/genética
9.
Opt Lett ; 48(2): 239-242, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36638427

RESUMEN

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.

10.
Cell Commun Signal ; 21(1): 366, 2023 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-38129877

RESUMEN

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.


Asunto(s)
Trampas Extracelulares , Vesículas Extracelulares , MicroARNs , Schistosoma japonicum , Ratones , Animales , Schistosoma japonicum/genética , Interleucina-10 , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Neutrófilos , Vesículas Extracelulares/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Macrófagos
11.
Protein Expr Purif ; 212: 106359, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37625736

RESUMEN

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.


Asunto(s)
Escherichia coli , Sesquiterpenos , Escherichia coli/genética
12.
Pharmacol Res ; 195: 106886, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37591326

RESUMEN

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.


Asunto(s)
Cirrosis Hepática , Semaforinas , Animales , Humanos , Masculino , Ratones , Aldehído Oxidasa , Antígenos CD , Cirrosis Hepática/genética , Ratones Noqueados , Semaforinas/genética
13.
J Org Chem ; 88(11): 6633-6644, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37133412

RESUMEN

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.

14.
Angew Chem Int Ed Engl ; 62(7): e202216534, 2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36536515

RESUMEN

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.

15.
Angew Chem Int Ed Engl ; 62(40): e202308091, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37340794

RESUMEN

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.

16.
Molecules ; 27(21)2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36364310

RESUMEN

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.


Asunto(s)
Aminoglicósidos , Kanamicina , Kanamicina/farmacología , Kanamicina/química , Aminoglicósidos/química , Antibacterianos/química , Relación Estructura-Actividad , Bioensayo , Acetiltransferasas
17.
Molecules ; 27(16)2022 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-36014361

RESUMEN

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.


Asunto(s)
Gases , Contaminantes Químicos del Agua , Adsorción , Derivados del Benceno , Dióxido de Silicio , Ácidos Sulfúricos , Contaminantes Químicos del Agua/química
18.
Opt Express ; 29(4): 5397-5406, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33726076

RESUMEN

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.

19.
Arch Biochem Biophys ; 709: 108986, 2021 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-34252391

RESUMEN

Tubers of Curcuma wenyujin are rich in essential oils, mainly various sesquiterpenes, showing antibacterial, anti-viral and anti-tumor effects. However, the molecular mechanism of C. wenyujin is deficient and related sesquiterpene synthases are still unclear. In this study, the transcriptome data of tubers and leaves from C. wenyujin were obtained and assembled into 78 092 unigenes. Of them, 244 unigenes were predicted to be involved in terpenoid biosynthesis while 131 unigenes were categorized as the "Terpenoid backbone biosynthesis" (TBB) term. Twenty-two unigenes possessed terpene synthase domain; five were predicted to be sesquiterpene synthases. Of the 208 unigenes annotated as cytochromes P450, 8 unigenes with full-length coding sequences were part of the CYP71 clade that primarily may perform hydroxylations of specialized metabolites. Furthermore, Ten DEGs related to the C5 precursor supply and sesquiterpene synthesis were validated by Real-time PCR; that showed a close correspondence with transcriptome sequence. A novel germacrene B synthase (CwGBS) and α-santalene synthase (CwSS) were identified in metabolically engineering E. coli. This study provided the first de novo transcriptome comparative analysis of leaf and tuber tissues from C. wenyujin, aiming to understand genetic mechanisms. Key genes involved in the biosynthesis of sesquiterpene will help for revealing the underlying mechanisms of C. wenyujin.


Asunto(s)
Transferasas Alquil y Aril/genética , Curcuma/genética , Genes de Plantas , Proteínas de Plantas/genética , Transcriptoma , Transferasas Alquil y Aril/química , Secuencia de Aminoácidos , Curcuma/química , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/genética , Bases de Datos Genéticas , Escherichia coli/genética , Perfilación de la Expresión Génica , Ontología de Genes , Hojas de la Planta/genética , Proteínas de Plantas/química , Tubérculos de la Planta/genética , RNA-Seq
20.
Molecules ; 26(4)2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33672689

RESUMEN

To expand the applications of graphene-based materials to biogas purification, a series of reduced graphene oxide aerogels (rGOAs) were prepared from industrial grade graphene oxide using a simple hydrothermal method. The influences of the hydrothermal preparation temperature on the textural properties, hydrophobicity and physisorption behavior of the rGOAs were investigated using a range of physical and spectroscopic techniques. The results showed that the rGOAs had a macro-porous three-dimensional network structure. Raising the hydrothermal treatment temperature reduced the number of oxygen-containing groups, whereas the specific surface area (SBET), micropore volume (Vmicro) and water contact angle values of the rGOAs all increased. The dynamic adsorption properties of the rGOAs towards hexamethyldisiloxane (L2) increased with increasing hydrothermal treatment temperature and the breakthrough adsorption capacity showed a significant linear association with SBET, Vmicro and contact angle. There was a significant negative association between the breakthrough time and inlet concentration of L2, and the relationship could be reliably predicted with a simple empirical formula. L2 adsorption also increased with decreasing bed temperature. Saturated rGOAs were readily regenerated by a brief heat-treatment at 100 °C. This study has demonstrated the potential of novel rGOA for applications using adsorbents to remove siloxanes from biogas.


Asunto(s)
Grafito/química , Siloxanos/química , Adsorción , Geles/química , Interacciones Hidrofóbicas e Hidrofílicas , Oxidación-Reducción , Tamaño de la Partícula , Propiedades de Superficie
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