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1.
Chemistry ; 30(37): e202400842, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38691421

RESUMO

Recent interest has surged in using heterogeneous carriers to boost synergistic photocatalysis for organic transformations. Heterogeneous catalysts not only facilitate synergistic enhancement of distinct catalytic centers compared to their homogeneous counterparts, but also allow for the easy recovery and reuse of catalysts. This mini-review summarizes recent advancements in developing heterogeneous carriers, including metal-organic frameworks, covalent-organic frameworks, porous organic polymers, and others, for synergistic catalytic reactions. The advantages of porous materials in heterogeneous catalysis originate from their ability to provide a high surface area, facilitate enhanced mass transport, offer a tunable chemical structure, ensure the stability of active species, and enable easy recovery and reuse of catalysts. Both photosensitizers and catalysts can be intricately incorporated into suitable porous carriers to create heterogeneous dual photocatalysts for organic transformations. Notably, experimental evidence from reported cases has shown that the catalytic efficacy of heterogeneous catalysts often surpasses that of their homogeneous analogues. This enhanced performance is attributed to the proximity and confinement effects provided by the porous nature of the carriers. It is expected that porous carriers will provide a versatile platform for integrating diverse catalysts, thus exhibiting superior performance across a range of organic transformations and appealing prospect for industrial applications.

2.
Bioorg Chem ; 147: 107380, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636432

RESUMO

The COVID-19 pandemic continues to pose a threat to global health, and sounds the alarm for research & development of effective anti-coronavirus drugs, which are crucial for the patients and urgently needed for the current epidemic and future crisis. The main protease (Mpro) stands as an essential enzyme in the maturation process of SARS-CoV-2, playing an irreplaceable role in regulating viral RNA replication and transcription. It has emerged as an ideal target for developing antiviral agents against SARS-CoV-2 due to its high conservation and the absence of homologous proteases in the human body. Among the SARS-CoV-2 Mpro inhibitors, non-peptidic compounds hold promising prospects owing to their excellent antiviral activity and improved metabolic stability. In this review, we offer an overview of research progress concerning non-peptidic SARS-CoV-2 Mpro inhibitors since 2020. The efforts delved into molecular structures, structure-activity relationships (SARs), biological activity, and binding modes of these inhibitors with Mpro. This review aims to provide valuable clues and insights for the development of anti-SARS-CoV-2 agents as well as broad-spectrum coronavirus Mpro inhibitors.


Assuntos
Antivirais , Proteases 3C de Coronavírus , Inibidores de Proteases , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Humanos , Antivirais/farmacologia , Antivirais/química , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Relação Estrutura-Atividade , Tratamento Farmacológico da COVID-19 , Estrutura Molecular , COVID-19/virologia
3.
J Clin Ultrasound ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38840562

RESUMO

Non-Hodgkin lymphoma (NHL) is a highly aggressive malignant tumor arising in lymph nodes or extra-nodal lymphoid tissues, with an incidence of 8.3 per million. It accounts for approximately 7% of childhood and adolescent malignancies, second only to leukemia and brain tumors. Despite the gastrointestinal tract being the most common extra-nodal site involved by lymphoma, primary intestinal lymphoma (PIL) is rare and typically affects middle-aged men without specific clinical symptoms. Here, we present the case of a 2-year-old child indicative of PIL with the informed consent of the parents.

4.
Zhonghua Nan Ke Xue ; 29(10): 934-937, 2023 Oct.
Artigo em Zh | MEDLINE | ID: mdl-38639665

RESUMO

Obstract: To explore the application of electrophysiological appropriate technology in perioperative nursing of patients undergoing microdissection testicular sperm extraction. METHODS: A retrospective analysis was conducted on the medical records of 108 patients who underwent testicular incision and sperm extraction under a microscope at our center from May 2022 to June 2023. Among them, 51 patients received routine care and 57 patients received electrophysiological treatment. Evaluate the perioperative nursing effects of appropriate electrophysiological techniques through VAS pain score, Self Rating Anxiety Scale (SAS) score, Pittsburgh Sleep Quality Score, and Kolcaba Comfort Scale. RESULT: Patients who received appropriate electrophysiological interventions had lower VAS pain scores (2.36 ± 1.37 vs 4.16 ± 1.38, P<0.001) than the control group, and higher KOLCABA comfort scale scores than the control group (70.73 ± 19.46 vs 52.06 ± 17.50, P<0.001); There was no statistically significant difference in the Self Rating Anxiety Scale (SAS) score and Pittsburgh Sleep Quality Score. CONCLUSION: Electrophysiological techniques can effectively improve postoperative pain and comfort in patients undergoing testicular incision and sperm extraction under a microscope, and have clinical application value.


Assuntos
Azoospermia , Ferida Cirúrgica , Humanos , Masculino , Azoospermia/cirurgia , Estudos Retrospectivos , Microdissecção , Enfermagem Perioperatória , Recuperação Espermática , Sêmen , Testículo/cirurgia , Espermatozoides , Dor
5.
Angew Chem Int Ed Engl ; 62(41): e202310470, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37615272

RESUMO

Porous organic polymers (POPs) have emerged as a novel class of porous materials that are synthesized by the polymerization of various organic monomers with different geometries and topologies. The molecular tunability of organic building blocks allows the incorporation of functional units for photocatalytic organic transformations. Here, we report the synthesis of two POP-based photocatalysts via homopolymerization of vinyl-functionalized diaryl dihydrophenazine (DADHP) monomer (POP1) and copolymerization of vinyl-functionalized DADHP and 2,2'-bipyridine monomers (POP2). The fluorescence lifetimes of DADHP units in the POPs significantly increased, resulting in enhanced photocatalytic performances over homogeneous controls. POP1 is highly effective in catalysing visible-light-driven C-N bond forming cross-coupling reactions. Upon coordination with Ni2+ ions, POP2-Ni shows strong synergy between photocatalytic and Ni catalytic cycles due to the confinement effect within the POP framework, leading to high efficiency in energy, electron, and organic radical transfer. POP2-Ni displays excellent activity in catalysing C-P bond forming reactions between diarylphosphine oxides and aryl iodides. They increased the photocatalytic activities by more than 30-fold in C-N and C-P cross-coupling reactions. These POP catalysts were readily recovered via centrifugal separation and reused in six catalytic cycles without loss of activities. Thus, photosensitizer-based POPs provide a promising platform for heterogeneous photocatalytic organic transformations.

6.
Eur J Nucl Med Mol Imaging ; 49(3): 847-860, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34505945

RESUMO

PURPOSE: Obtaining tumour-free margins is critical for avoiding re-excision and reducing local recurrence following breast-conserving surgery; however, it remains challenging. Imaging-guided surgery provides precise detection of residual lesions and assists surgical resection. Herein, we described water-soluble melanin nanoparticles (MNPs) conjugated with cyclic Arg-Gly-Asp (cRGD) peptides for breast cancer photoacoustic imaging (PAI) and surgical navigation. METHODS: The cRGD-MNPs were synthesised and characterized for morphology, photoacoustic characteristics and stability. Tumour targeting and toxicity of cRGD-MNPs were determined by using either breast cancer cells, MDA-MB-231 tumour-bearing mice or the FVB/N-Tg (MMTV-PyVT) 634Mul/J mice model. PAI was used to locate the tumour and guide surgical resection in MDA-MB-231 tumour-bearing mice. RESULTS: The cRGD-MNPs exhibited excellent in vitro and in vivo tumour targeting with low toxicity. Intravenous administration of cRGD-MNPs to MDA-MB-231 tumour-bearing mice showed an approximately 2.1-fold enhancement in photoacoustic (PA) intensity at 2 h, and the ratio of the PA intensity at the tumour site to that in the surrounding normal tissue was 3.2 ± 0.1, which was higher than that using MNPs (1.7 ± 0.3). Similarly, the PA signal in the spontaneous breast cancer increased ~ 2.5-fold at 2 h post-injection of cRGD-MNPs in MMTV-PyVT transgenic mice. Preoperative PAI assessed tumour volume and offered three-dimensional (3D) reconstruction images for accurate surgical planning. Surgical resection following real-time PAI showed high consistency with histopathological analysis. CONCLUSION: These results highlight that cRGD-MNP-mediated PAI provide a powerful tool for breast cancer imaging and precise tumour resection. cRGD-MNPs with fine PA properties have great potential for clinical translation.


Assuntos
Neoplasias da Mama , Nanopartículas , Técnicas Fotoacústicas , Cirurgia Assistida por Computador , Animais , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Feminino , Humanos , Melaninas/química , Camundongos , Nanopartículas/química , Oligopeptídeos , Técnicas Fotoacústicas/métodos , Cirurgia Assistida por Computador/métodos
7.
Eur J Neurosci ; 53(1): 140-150, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-31491043

RESUMO

The role of the fibroblast growth factor (FGF) system in depression has received considerable attention in recent years. To understand the role of this system, it is important to identify the specific members of the FGF family that have been implicated and the various mechanisms that they modulated. Here, we review the role of FGFs in depression and integrate evidence from clinical and basic research. These data suggest that changes in the FGF family are involved in depression and possibly in a wider range of psychiatric disorders. We analyse the abnormalities of FGF family members in depression and their roles in modulating depression-related molecules. The role of the FGF family in depression and related disorders needs to be studied in more detail.


Assuntos
Depressão , Transtornos Mentais , Fatores de Crescimento de Fibroblastos/genética , Humanos , Receptores de Fatores de Crescimento de Fibroblastos
8.
Org Biomol Chem ; 19(47): 10296-10313, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34812834

RESUMO

Phosphoramide, as an important framework of many biologically active molecules, has attracted widespread attention in recent decades. It is not only widely used in pharmaceuticals because of its excellent biological activities, but it also shows good performance in organic dyes, flame retardants and extractors. Thus, it is of great significance to develop effective and convenient methods for the synthesis of phosphoramides. In this review, the recent advancements made in the synthesis routes and applications of phosphoramides are discussed. The synthetic strategies of phosphoramides can be separated into five categories: phosphorus halides as the substrate, phosphates as the substrate, phosphorus hydrogen as the substrate, azides as the substrate and other methods. The latest examples of these methods are provided and some representative mechanisms are also described.

9.
Bioorg Med Chem ; 55: 116597, 2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-34995858

RESUMO

The α- and ß-tubulins are the major polypeptide components of microtubules (MTs), which are attractive targets for anticancer drug development. Indole derivatives display a variety of biological activities including antitumor activity. In recent years, a great number of indole derivatives as tubulin polymerization inhibitors have sprung up, which encourages medicinal chemists to pursue promising inhibitors with improved antitumor activities, excellent physicochemical, pharmacokinetic and pharmacodynamic properties. In this review, the recent progress from 2010 to present in the development of indole derivatives as tubulin polymerization inhibitors was summarized and reviewed, which would provide useful clues and inspirations for further design of outstanding tubulin polymerization inhibitors.

10.
Childs Nerv Syst ; 37(1): 253-257, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32533299

RESUMO

PURPOSE: Tuberous sclerosis complex (TSC) is an autosomal dominant multisystem disorder characterized by hamartomas in multiple organ systems. The TSC1 and TSC2 genes have been identified as the genetic basis of TSC. Two gene tests were used for definitive genetic diagnosis. METHODS: In our study, the case of a Chinese pediatric patient with seizures, hypomelanotic macules, hyperpigmented patches, multiple parenchymal lesions in the ventricle, and developmental retardation is detailed. Whole-genome sequencing (WGS) and multiplex ligation-dependent probe amplification (MLPA) were employed to detect genetic variations and copy number variations of TSC1 and TSC2. RESULTS: A novel heterozygous nonsense mutation in the TSC2 gene (c.3751A>T, p.Lys1251Ter) was identified in a Chinese pediatric patient suffering from TSC, whose unaffected parents did not carry this mutation. The mutation was classified as "pathogenic" according to the American College of Medical Genetics (ACMG) guidelines. CONCLUSION: WGS was carried out to definitively diagnose and detect variations in the exon and noncoding region of the gene and copy number variations in the whole genome simultaneously. For diseases with complex genetic mechanisms, WGS as the first-line test can be efficient and cost-effective for clinical diagnosis.


Assuntos
Códon sem Sentido , Esclerose Tuberosa , Criança , Variações do Número de Cópias de DNA , Humanos , Mutação , Esclerose Tuberosa/genética , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética
11.
Inorg Chem ; 59(11): 7398-7407, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32401025

RESUMO

The development of new spin-crossover complexes provides novel promising switching materials with significant potential at the molecular level. Ter-imine-type molecules represent one of the important classes of ligands in creating SCO-active complexes. Herein we report a family of mononuclear Fe(II) SCO-active compounds constructed from a new type of ter-imine ligand named the thio-pybox ligand (2,6-bis(4,4-dimethyl-4,5-dihydrothiazol-2-yl)pyridine, L1). Through the variation of counteranions, some cases display complete SCO and with T1/2 near ambient temperature. Among them, annealed [FeII(L1)2](ClO4)2 [1(ClO4)] shows T1/2↓ and T1/2↑ as 319 and 349 K, respectively. The wide thermal hysteresis of ΔT = 30 K originated from the weak interaction between complex cations and counteranions in the crystal lattice. Impressively, its high-spin population can be increased considerably by annealing at high temperature. The metastable high-spin phase is stable in the successive magnetic measurements and would gradually relax to its initial state with high population of low-spin configuration at ambient temperature. In acetonitrile-diluted solution, 1(ClO4) still maintains SCO with an estimated T1/2 at 240 K. Differential scanning calorimetry discloses the structural phase at around 355 K in the first heating process and the increase in the high-spin population concomitant with annealing was also corroborated by 57Fe Mössbauer measurements. Additionally, the influences on SCO by counteranion and ligand structure are investigated, which show that the fine tuning of complex structures can affect the behavior of the spin state significantly. Finally, magneto-structural correlation studies were performed on the structures of 1(ClO4) and its oxygen analogue at multiple temperatures. The analyses of some structural parameters, including terminal N···N donor separation, bite angle, patulous angle, and the root mean squared deviation indicate that the replacement of the oxygen atom with a sulfur atom can effectively improve the flexibility and release the steric strain and thus tune the SCO toward ambient temperature. Our research demonstrates the rational design of the ligand can lead to new SCO-active compounds with high performance.

12.
J Orthop Sci ; 25(4): 708-714, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31607516

RESUMO

BACKGROUND: The use of 3D-printed scaffolds in repairing bone defects remains unexplored. We aimed to determine whether the duration of electrochemical deposition (ECD) affects the properties of hydroxyapatite (HA) coatings on 3D-printed titanium (TI) scaffolds as well as the corresponding phenotype of MC3T3-E1 cells seeded on these surfaces. METHODS: Five groups of HA-coated TI scaffolds were produced using different durations of ECD (0, 5, 10, 20, and 30 min) and examined under scanning electron microscopy (SEM). MC3T3-E1 cell adhesion to the HA-coated scaffolds and subsequent proliferation and viability were assessed using SEM, DAPI staining, EdU staining, and Alamar Blue assay, respectively. MC3T3-E1 cell expression of osteogenic genes was analyzed by fluorescence RT-PCR. RESULTS: On SEM, longer ECD durations resulted in more compact HA crystals of differing morphology coated onto the TI scaffolds. MC3T3-E1 cell adhesion differed among the five groups (p < 0.05), with the largest number of cells adhered to the scaffolds prepared with 30 min of ECD, followed by the group prepared with 20 min of ECD. However, the ECD duration of 20 min was associated with the highest cell viability and proliferation rate (both p < 0.05) as well as the highest mRNA expression levels of alkaline phosphatase, collagen I, osteocalcin and runt-related transcription factor 2 among the five groups (p < 0.05). CONCLUSIONS: In the fabrication of HA-coated 3D printed TI scaffolds, an ECD duration of 20 min resulted in scaffolds that best promoted MC3T3-E1 cell viability, proliferation and osteogenic gene expression.


Assuntos
Materiais Biocompatíveis , Adesão Celular/fisiologia , Durapatita , Osteogênese , Impressão Tridimensional , Alicerces Teciduais , Titânio , Células 3T3 , Animais , Camundongos , Fatores de Tempo
13.
Zhonghua Nan Ke Xue ; 26(8): 686-694, 2020 Aug.
Artigo em Zh | MEDLINE | ID: mdl-33377728

RESUMO

OBJECTIVE: To study the miR-184 level in the seminal plasma exosome of male infertility patients and its clinical significance. METHODS: Between 2015 and 2019, we collected 285 seminal plasma samples from 97 azoospermia (AS) and 96 asthenospermia (AZS) patients and 92 age-matched normal fertile controls in Jiangsu Provincial Hospital of Traditional Chinese Medicine, General Hospital of Eastern Theater Command and the First Hospital Affiliated to Wenzhou Medical University, identified the isolated seminal plasma exosomes by nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM) and Western blot, and detected the miR-184 level in the seminal plasma exosomes by quantitative real-time PCR (qRT-PCR). We determined the clinical value of the miR-184 level and its correlation with semen parameters by multiple statistics, predicted the target genes and involved pathways of miR-184 by bioinformatic algorithms, and analyzed their relationship with male infertility. RESULTS: NTA, TEM and Western blot exhibited plenty of exosomes in the seminal plasma of the patients. The results of qRT-PCR showed that the miR-184 level in the seminal plasma exosome was dramatically decreased in the AS patients compared with that in the normal fertile controls (0.227 [0.092, 0.790] vs 0.650 [0.408, 1.061], P < 0.01), but increased in AZS males in comparison with that in the control group (1.176 [0.661, 1.946] vs 0.650 [0.408, 1.061], P < 0.01). The areas under the ROC curve (AUC) for differentiating the AS and AZS patients from the controls were 0.866 (95% CI: 0.815-0.916) and 0.724 (95% CI: 0.653-0.795), respectively, and that for differentiating the AS from the AZS group was 0.964 (95% CI: 0.943-0.985). The miR-184 level in the seminal plasma exosome of the AZS patients was correlated positively with the sperm count (r = 0.243, P = 0.017) but negatively with the percentage of progressively motile sperm (r = -0.407, P = 0.006). Bioinformatics analysis indicated that the downstream target genes of miR-184 were significantly enriched in the protein regulatory pathways closely related to male reproduction and spermatogenesis. CONCLUSIONS: The miR-184 level in the seminal plasma exosome of infertility patients is significantly different from that of normal fertile males, which may serve as a potential auxiliary marker for the diagnosis of and participate in the development and progression of male infertility.


Assuntos
Exossomos , Infertilidade Masculina , MicroRNAs/genética , Sêmen/química , Azoospermia , Estudos de Casos e Controles , Exossomos/genética , Humanos , Infertilidade Masculina/genética , Masculino , Contagem de Espermatozoides , Motilidade dos Espermatozoides
14.
J Am Chem Soc ; 141(1): 175-181, 2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30525565

RESUMO

A novel fluorescent probe based on a bisbinaphthyl structure has been designed and synthesized. This compound in combination with Zn(II) has exhibited highly enantioselective fluorescence enhancement with 13 common free amino acids. For example, its enantiomeric fluorescent enhancement ratios ( ef or Δ IL/Δ ID) in the presence of the following amino acids are extremely high: 177 for valine, 199 for methionine, 186 for phenylalanine, 118 for leucine, and 89 for alanine. The observed high enantioselectivity and the extent of the substrate scope are unprecedented in the fluorescent recognition of free amino acids. This fluorescent probe can be applied to determine the enantiomeric composition of the structurally diverse chiral amino acids. NMR and mass spectroscopic investigations have provided clues to elucidate the observed high enantioselectivity.

15.
Chemistry ; 25(33): 7866-7873, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-30893491

RESUMO

A fluorophilic fluorescent probe based on a perfluoroalkyl-substituted bis(binaphthyl) compound was designed and synthesized. It displayed a highly enantioselective fluorescence response toward structurally diverse amino acids in a biphasic fluorous/aqueous system with enantiomeric fluorescent enhancement ratio (ef; ΔID /ΔIL ) values up to 45.2 (histidine). It can be used to determine the enantiomeric compositions of amino acids and also allows the amino acid enantiomers to be visually discriminated. NMR and mass-spectroscopic investigations provided insights into the observed high enantioselectivity. This biphasic fluorescent recognition was used to determine the enantiomeric composition of the crude phenylalanine products generated by an enzyme-catalyzed asymmetric hydrolysis under various reaction conditions. The fluorous-phase-based fluorescence measurement under the biphasic conditions was able to minimize the interference of other reaction components and thus has potential in asymmetric reaction screening.

16.
J Am Chem Soc ; 140(16): 5326-5329, 2018 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-29578703

RESUMO

We report the design of two new metal-organic frameworks (MOFs), Ru-TBP and Ru-TBP-Zn, based on Ru2 secondary building units (SBUs) and porphyrin-derived tetracarboxylate ligands. The proximity of Ru2 SBUs to porphyrin ligands (∼1.1 nm) facilitates multielectron transfer from excited porphyrins to Ru2 SBUs to enable efficient visible-light-driven hydrogen evolution reaction (HER) in neutral water. Photophysical and electrochemical studies revealed oxidative quenching of excited porphyrin by Ru2 SBUs as the initial step of the HER process and the energetics of key intermediates in the catalytic cycle. Our work provides a new strategy to building multifunctional MOFs with synergistic ligands and SBUs for efficient photocatalysis.

17.
J Am Chem Soc ; 140(39): 12369-12373, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30220196

RESUMO

Metal-organic layers (MOLs), a free-standing monolayer version of two-dimensional metal-organic frameworks (MOFs), have emerged as a new class of 2D materials for many potential applications. Here we report the design of a new photosensitizing MOL, Hf12-Ru, based on Hf12 secondary building units (SBUs) and [Ru(bpy)3]2+ (bpy = 2,2'-bipyridine) derived dicarboxylate ligands. After modifying the SBU surface of Hf12-Ru with M(bpy)(CO)3X (M = Re and X = Cl or M = Mn and X = Br) derived capping molecules through carboxylate exchange reactions, the resultant Hf12-Ru-Re and Hf12-Ru-Mn MOLs possess both [Ru(bpy)3]2+ photosensitizers and M(bpy)(CO)3X catalysts for efficient photocatalytic CO2 reduction. The proximity of the MOL skeleton to the capping ligands (1-2 nm) facilitates electron transfer from the reduced photosensitizer [Ru(bpy)3]+ to MI(bpy)(CO)3X (M = Re, Mn) catalytic centers, resulting in CO2 reduction turnover numbers of 8613 under artificial visible light and of 670 under sunlight. MOLs thus represent a novel platform to assemble multifunctional materials for studying artificial photosynthesis.

19.
Angew Chem Int Ed Engl ; 57(43): 14090-14094, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-30129281

RESUMO

Metal-organic frameworks (MOFs) have been extensively used for single-site catalysis and light harvesting, but their application in multicomponent photocatalysis is unexplored. We report here the successful incorporation of an IrIII photoredox catalyst and a NiII cross-coupling catalyst into a stable Zr12 MOF, Zr12 -Ir-Ni, to efficiently catalyze C-S bond formation between various aryl iodides and thiols. The proximity of the IrIII and NiII catalytic components to each other (ca. 0.6 nm) in Zr12 -Ir-Ni greatly facilitates electron and thiol radical transfers from Ir to Ni centers to reach a turnover number of 38 500, an order of magnitude higher than that of its homogeneous counterpart. This work highlights the opportunity in merging photoredox and organometallic catalysts in MOFs to effect challenging organic transformations.

20.
Cytokine ; 92: 110-117, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28142109

RESUMO

Thrombopoietin receptor agonists (TPO-RAs) have been clinically used in primary immune thrombocytopenia (ITP) with favorable outcomes, while their effect on cytokine regulation in ITP remains unknown. In the present study, plasma and mRNA expression levels of interleukin (IL)-2, interferon gamma (IFN-γ), IL-4, IL-17A, and transforming growth factor-ß1 (TGF-ß1) were determined by ELISA and real-time quantitative PCR in 26 corticosteroid-resistant/relapsed ITP patients receiving eltrombopag or rhTPO therapy and 15 healthy controls (HCs). Results showed that plasma and mRNA levels of IL-2, IFN-γ, IL-4, and IL-17A in ITP patients did not change significantly after TPO-RA treatment, whereas TGF-ß1 levels increased remarkably. The pre- and post-treatment plasma and mRNA levels of IFN-γ and IL-2 were significantly higher, while the pre- and post-treatment IL-4 levels as well as the pre-treatment TGF-ß1 levels were remarkably lower in ITP patients compared with HCs. There was no significant difference in TGF-ß1 levels between TPO-RA-treated ITP patients and HCs. No statistical difference was found in plasma levels of IL-17A between ITP patients before or after treatment and HCs. However, the pre- and post-treatment mRNA expression of IL-17A and retinoic orphan receptor (ROR) γt in ITP patients were higher than that in HCs. Overall, these findings indicated that TPO-RA treatment could promote the secretion of TGF-ß1, while it could not correct the Th1 and Th17 polarization in ITP patients. This study might improve our understanding of the mechanism of action of TPO-RAs and provide important information for optimizing therapeutic strategies for ITP.


Assuntos
Benzoatos/administração & dosagem , Citocinas/sangue , Hidrazinas/administração & dosagem , Púrpura Trombocitopênica Idiopática/sangue , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Pirazóis/administração & dosagem , Receptores de Trombopoetina/agonistas , Trombopoetina/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/sangue , Células Th1/metabolismo , Células Th17/metabolismo
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