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1.
Angew Chem Int Ed Engl ; : e202410010, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926253

RESUMO

Porous frameworks with controlled pore structure and tunable aperture are greatly demanded. However, precise synthesis of this kind of materials is a formidable challenge. Herein, we report the fabrication of two-dimensional (2D) supramolecular polymer frameworks using a precisely synthesized rod-like helical polyisocyanide as link. Four three-arm star-shaped polyisocyanides with the degree of the polymerization of 10, 20, 30 and 40, and having 2-ureido-4[1H]-pyrimidinone (UPy) terminals were synthesized. 2D-Crystalline polymer frameworks with apertures of 5.3, 10.1, 13.9, and 19.1 nm were respectively obtained through intermolecular hydrogen bonding interaction between the terminal Upy units. The pore aperture is dependent on the length of polyisocyanide backbone. Thus, well-defined supramolecular polymer frameworks with controlled and uniform hexagonal pores were obtained, as proved by small-angle X-ray scattering (synchrotron radiation facility), atomic force microscopy, and Brunauer-Emmett-Teller analyses. The frameworks with uniform large pore aperture were used to purify nanomaterials and immobilize biomacromolecules. For instance, the membranes of the polymer frameworks could size-fractionation of silver nanoparticles into uniform nanoparticles with very low dispersity. The frameworks with large aperture facilitated the inclusion of myoglobin and enhanced the stability and catalytic activity.

2.
Environ Sci Technol ; 57(25): 9394-9404, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37311080

RESUMO

Electron paramagnetic resonance (EPR) spectroscopy using sterically hindered amine is extensively applied to detect singlet oxygen (1O2) possibly generated in advanced oxidation processes. However, EPR-detectable 1O2 signals were observed in not only the 1O2-dominated hydrogen peroxide (H2O2)/hypochlorite (NaClO) reaction but surprisingly also the 1O2-absent Fe(II)/H2O2, UV/H2O2, and ferrate [Fe(VI)] process with even stronger intensities. By taking advantage of the characteristic reaction between 1O2 and 9,10-diphenyl-anthracene and near-infrared phosphorescent emission of 1O2, 1O2 was excluded in the Fe(II)/H2O2, UV/H2O2, and Fe(VI) process. The false detection of 1O2 was ascribed to the direct oxidation of hindered amine to piperidyl radical by reactive species [e.g., •OH and Fe(VI)/Fe(V)/Fe(IV)] via hydrogen transfer, followed by molecular oxygen addition (forming a piperidylperoxyl radical) and back reaction with piperidyl radical to generate a nitroxide radical, as evidenced by the successful identification of a piperidyl radical intermediate at 100 K and theoretical calculations. Moreover, compared to the highly oxidative species (e.g., •OH and high-valence Fe), the much lower reactivity of 1O2 and the profound nonradiative relaxation of 1O2 in H2O resulted it too selective and inefficient in organic contaminant destruction. This study demonstrated that EPR-based 1O2 detection could be remarkably misled by common oxidative species and thereby jeopardize the understandings on 1O2.


Assuntos
Peróxido de Hidrogênio , Oxigênio Singlete , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Peróxido de Hidrogênio/química , Oxigênio , Oxirredução , Compostos Ferrosos
3.
Environ Sci Technol ; 57(32): 12094-12104, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37490389

RESUMO

In this study, Ru(III) ions were utilized to activate periodate (PI) for oxidation of trace organic pollutants (TOPs, e.g., carbamazepine (CBZ)). The Ru(III)/PI system can significantly promote the oxidation of CBZ in a wide initial pH range (3.0-11.0) at 1 µM Ru(III), showing much higher performance than transition metal ions (i.e., Fe(II), Co(II), Zn(II), Fe(III), Cu(II), Ni(II), Mn(II), and Ce(III)) and noble metal ion (i.e., Ag(I), Pd(II), Pt(II), and Ir(III)) activated PI systems. Probe experiments, UV-vis spectra, and X-ray absorption near-edge structure (XANES) spectra confirmed high-valent Ru-oxo species (Ru(V)=O) as the dominant oxidant in the process. Because of the dominant role of Ru(V)=O, the Ru(III)/PI process exhibited a remarkable selectivity and strong anti-interference in the oxidation of TOPs in complex water matrices. The Ru(V)=O species can undertake 1-e- and 2-e- transfer reactions via the catalytic cycles of Ru(V)=O → Ru(IV) → Ru(III) and Ru(V)=O → Ru(III), respectively. The utilization efficiency of PI in the Ru(III)/PI process for the oxidation of TOPs can approach 100% under optimal conditions. PI stoichiometrically transformed into IO3- without production of undesired iodine species (e.g., HOI and I2). This study developed an efficient and environmentally benign advanced oxidation process for rapid removal of TOPs and enriched understandings on reactivity of Ru(V)=O and Ru catalytic cycles.


Assuntos
Poluentes Ambientais , Compostos Férricos , Metais , Oxirredução , Água/química
4.
J Clin Monit Comput ; 37(2): 593-598, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36308611

RESUMO

To compare the potential influences of blind insertion and up-down optimized glottic exposure manoeuvre on the oropharyngeal leak pressure (OPLP) in using SaCoVLM™ video laryngeal mask (VLM) among patients undergoing general anesthesia. A randomized self-control study controlled was conducted to investigate the effect of two insertion techniques on OPLP. A total of 60 patients (male or female, 18-78 years, BMI 18.0-30.0 kg m-2 and ASA I-II) receiving selective surgery under general anesthesia were randomly recruited. After induction of anesthesia, the SaCoVLM™ was inserted by blind insertion manoeuvre. The glottic exposure grading(V1) of the SaCoVLM™ visual laryngeal mask and the OPLP(P1) were recorded. And the glottic exposure grading(V2) and OPLP(P2) of SaCoVLM™ were recorded again when the glottic exposure grading was optimal. The glottis exposure grading and OPLP were compared before and after different insertion manoeuver. The glottic exposure grading (V2) obtained by using up-down optimized glottic exposure manoeuvre was better than that obtained by using blind insertion manoeuvre (V1)(P < 0.001). The OPLP was significantly lower in the blind insertion manoeuvre (P1) than in the up-down optimized glottic exposure manoeuvre (P2) (32.4 ± 5.0 cmH2O vs. 36.3 ± 5.2 cmH2O, P < 0.001). In using SaCoVLM™, higher OPLP and better glottic exposure grading were achieved through up-down optimized glottic exposure manoeuvre, protecting the airway while real-time monitoring of conditions around the glottis, which significantly improves airway safety. Our results suggests that up-down optimized glottic exposure manoeuver may be a useful technique for SaCoVLM™ insertion.Trial registration: ChiCTR, ChiCTR2000028802. Registered 4 January 2020, http://www.chictr.org.cn/ChiCTR2000028802.


Assuntos
Anestesiologia , Máscaras Laríngeas , Humanos , Masculino , Feminino , Anestesia Geral/métodos , Intubação Intratraqueal/métodos , Glote
5.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(6): 997-1004, 2023 Dec 30.
Artigo em Zh | MEDLINE | ID: mdl-38173113

RESUMO

Melatonin,an endocrine hormone synthesized by the pineal gland,plays an important role in the reproduction.The growth and development of follicles is the basis of female mammalian fertility.Follicles have a high concentration of melatonin.Melatonin receptors exist on ovarian granulosa cells,follicle cells,and oocytes.It regulates the growth and development of these cells and the maturation and atresia of follicles,affecting female fertility.This paper reviews the protective effects and regulatory mechanisms of melatonin on the development of ovarian follicles,granulosa cells,and oocytes and makes an outlook on the therapeutic potential of melatonin for ovarian injury,underpinning the clinical application of melatonin in the future.


Assuntos
Melatonina , Animais , Feminino , Melatonina/farmacologia , Folículo Ovariano , Oócitos , Células da Granulosa/fisiologia , Mamíferos
6.
Cell Tissue Res ; 388(2): 301-312, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35192037

RESUMO

N6-methyladenosine (m6A) modification plays a crucial role in the progression of osteoporosis (OP). The study aimed to explore the effects of methyltransferase-like 3 (METTL3) in OP. The levels of METTL3, LINC00657, miR-144-3p and BMPR1B were detected using qPCR. Osteogenesis was assessed using alizarin red and alkaline phosphatase (ALP) staining assays. The protein expression of Bglap, Runx2 and Col1a1 was measured by western blot. The targets of LINC00657 and miR-144-3p were screened by bioinformatic analysis. The interaction between miR-144-3p and LINC00657 or BMPR1B was analyzed by dual-luciferase reporter assay and RNA pull-down assay. The results showed that METTL3 was downregulated in OP. METTL3 mediated m6A methylation of LINC00657 to promote the development of osteogenesis. Further study indicated that LINC00657 functioned as a ceRNA to upregulate BMPR1B via sponging miR-144-3p. Additionally, BMPR1B knockdown alleviated the effects of METTL3 on osteogenesis of bone marrow mesenchymal stem cells (BMSCs). Taken together, METTL3 facilitated osteogenic differentiation of BMSCs via the LINC00657/miR-144-3p/BMPR1B axis. Our findings may provide a novel insight of m6A methylation in the development of OP.


Assuntos
Células-Tronco Mesenquimais , MicroRNAs , Osteoporose , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Diferenciação Celular/genética , Células Cultivadas , Humanos , Metiltransferases/genética , Metiltransferases/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Osteogênese/genética , Osteoporose/genética , Osteoporose/metabolismo
7.
BMC Anesthesiol ; 22(1): 3, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979936

RESUMO

BACKGROUND: To preliminary evaluate the application of SaCoVLM™ video laryngeal mask airway in airway management of general anesthesia. METHODS: We recruited 100 adult patients (ages 18-78 years, male 19, female 81, weight 48-90 kg) with normal predicted airway (Mallampati I ~ II, unrestricted mouth opening, normal head and neck mobility) and ASA I-II who required general anaesthesia. The SaCoVLM™ was inserted after anesthesia induction and connected with the anesthesia machine for ventilation. Our primary outcome was glottic visualization grades. Secondary outcomes included seal pressure, success rate of insertion, intraoperative findings (gastric reflux and contraposition), gastric drainage and 24-h complications after operation. RESULTS: The laryngeal inlet was exposed in all the patients and shown on the video after SaCoVLM™ insertion. The status of glottic visualization was classified: grade 1 in 55 cases, grade 2 in 23 cases, grade 3 in 14 cases and grade 4 in 8 cases. The first-time success rate of SaCoVLM™ insertion was 95% (95% CI = 0.887 to 0.984), and the total success rate was 96% (95% CI = 0.901 to 0.989). The sealing pressure of SaCoVLM™ was 34.1 ± 6.2 cmH2O and the gastric drainage were smooth. Only a small number of patients developed mild complications after SaCoVLM™ was removed (such as blood stains on SaCoVLM™ and sore throat). CONCLUSIONS: The SaCoVLM™ can visualize partial or whole laryngeal inlets during the surgery, with a high success rate, a high sealing pressure and smooth gastroesophageal drainage. SaCoVLM™ could be a promise new effective supraglottic device to airway management during general anesthesia. TRIAL REGISTRATION: ChiCTR, ChiCTR2000028802 .Registered 4 January 2020.


Assuntos
Manuseio das Vias Aéreas/métodos , Anestesia Geral/métodos , Máscaras Laríngeas/estatística & dados numéricos , Máscaras Laríngeas/normas , Adolescente , Adulto , Idoso , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
8.
BMC Anesthesiol ; 22(1): 302, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36138363

RESUMO

BACKGROUND: When a difficult airway is unanticipatedly encountered and the initial laryngoscopic intubation fails, a supraglottic airway device (SAD) may be placed to aid ventilation and oxygenation, and act as a conduit for intubation. SaCoVLM™, as new SAD, can offer a direct vision to guide intubation. However, no study has evaluated the performance of SaCoVLM™ video laryngeal mask (VLM) intubation and i-gel combined with flexible bronchoscopy (FB)-guided intubation in airway management during general anesthesia. METHODS: A total of 120 adult patients were randomly allocated into the SaCoVLM™ group (Group S) and i-gel group (Group I). After induction of general anesthesia, guided tracheal intubation under direct vision of the SaCoVLM™ was conducted in Group S, while Group I received FB-guided tracheal intubation using the i-gel. The success rate of SAD placement, first-pass success rate of guided tracheal tube placement, and total success rate in both groups were recorded. The time for SAD placement, time for guided tracheal intubation, total intubation time (time for SAD placement and intubation), glottic exposure grading and postoperative intubation complications (i.e., dysphagia, hoarseness, pharyngalgia, etc.) of both groups were also compared. RESULTS: The first-time success rate of SAD placement was 98% in two groups. The first-pass success rate of guided endotracheal intubation was 92% in Group S and 93% in Group I (P = 0.74 > 0.05). The total intubation time was 30.8(± 9.7) s and 57.4(± 16.6) s (95% CI = -31.5 to -21.7) in Group S and Group I, respectively (P < 0.01). The total complication rate was 8% in Group S and 22% in Group I (P < 0.05). The laryngeal inlet could be observed in the S group through the visual system of SaCoVLM™. No dysphagia or hoarseness was reported. CONCLUSION: SaCoVLM™ can reveal the position of laryngeal inlet, thus providing direct vision for tracheal intubation. SaCoVLM™ -guided intubation is faster, and does not rely on FB, compared to i-gel combined with FB-guided intubation. Besides, SaCoVLM™ has a lower post-intubation complication rate. TRIAL REGISTRATION: Chinese Clinical Trials Registry (ChiCTR2100043443); Date of registration: 18/02/2021.


Assuntos
Transtornos de Deglutição , Máscaras Laríngeas , Adulto , Manuseio das Vias Aéreas , Anestesia Geral , Broncoscopia , Desenho de Equipamento , Tecnologia de Fibra Óptica , Rouquidão/etiologia , Humanos , Intubação Intratraqueal , Complicações Pós-Operatórias
9.
Chem Biodivers ; 19(7): e202200218, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35689671

RESUMO

Three new alkamides, achilleamide B-D (1-3) along with five known alkamides (4-8) were isolated from the aerial parts of Achillea alpina L. Structures were elucidated by spectroscopic analysis. Modified Mosher's method and electronic circular dichroism (ECD) calculations were introduced for the absolute configuration of 3. The neuroprotective effects of all the compounds were evaluated by 6-hydroxydopamine (6-OHDA)-induced cell death in human neuroblastoma SH-SY5Y cells, with concentration for 50 % of maximal effect (EC50 ) values of 3.16-24.75 µM, and the structure-activity relationship was conducted.


Assuntos
Achillea , Neuroblastoma , Fármacos Neuroprotetores , Achillea/química , Humanos , Estrutura Molecular , Fármacos Neuroprotetores/química , Componentes Aéreos da Planta/química
10.
Pharm Dev Technol ; 27(10): 1069-1082, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36422997

RESUMO

This study was designed to evaluate paraffin wax as a potential controlled release matrix for spray congealing and its impact on drug release and stability of the microparticles. Paraffin wax can form a hydrophobic barrier to moisture and reduce drug degradation besides retarding drug release in the gastrointestinal tract. More hydrophilic lipid-based additives can be incorporated to modulate the drug release through the paraffin wax barrier. This study reports the findings of lipid-wax formulations at preserving the stability of moisture-sensitive drugs in spray-congealed microparticles. Aspirin-loaded microparticles formulated with different drug loads, lipid additives, and lipid:wax ratios were produced by spray congealing. Stearic acid (SA), cetyl alcohol (CA), and cetyl ester (CE) were the lipid additives studied. The microparticles were evaluated for yield, encapsulation efficiency, particle size, drug stability, and release. CE exhibited the greatest effect on increasing drug release, followed by CA and SA. Dissolution profiles showed the best fit to Weibull kinetic model. The degree of drug degradation was low, with CA imparting the least protective effect, followed by SA and CE. Paraffin wax is useful for preserving the stability of moisture-sensitive aspirin and retarding its release from spray-congealed microparticles. The addition of lipid additives modulated drug release without compromising drug stability.


Assuntos
Álcoois Graxos , Parafina , Liberação Controlada de Fármacos , Composição de Medicamentos , Tamanho da Partícula
11.
Zhongguo Zhong Yao Za Zhi ; 47(18): 4919-4926, 2022 Sep.
Artigo em Zh | MEDLINE | ID: mdl-36164901

RESUMO

The present study designed and prepared near-infrared responsive sinomenine hydrochloride(SIN) reservoir microneedles and evaluated the feasibility of this type of microneedles in increasing the drug loading and transdermal absorption by characterizing their mechanical properties and in vitro release characteristics.SIN was selected as the model drug, and methoxy poly(ethylene glycol) poly(caprolactone)(mPEG-PCL) copolymers and indocyanine green(ICG) were employed as amphiphilic block copolymers and light inductor to prepare near-infrared responsive nanoparticles.Based on the preparation principle of bubble microneedles, near-infrared responsive SIN reservoir microneedles were designed and prepared.The features of the near-infrared responsive SIN reservoir microneedles were characterized by measuring the morphology, length, mechanical properties, and skin penetration of microneedles.Meanwhile, the drug release performance of reservoir microneedles was evaluated by in vitro release assay.The results showed that the prepared SIN microneedles were conical, with an exposed tip height of about 650 µm.Each needle could load about 0.5 mg of drugs per square centi-meter, and this type of microneedle showed good mechanical properties and performance in skin penetration.The results of the in vitro release assay showed that the 24 h cumulative release per unit area and release rate of the microneedle were 825.61 µg·cm~(-2) and 74.3%, respectively, which indicated that its release kinetics was in line with the first-order kinetic model.This study preliminarily proved that the reservoir microneedle could effectively increase the drug loading with good mechanical properties and release perfor-mance.


Assuntos
Verde de Indocianina , Morfinanos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Agulhas , Polietilenoglicóis
12.
J Cell Physiol ; 236(1): 284-293, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32592173

RESUMO

Bone marrow mesenchymal stem cells (BMSCs) can be induced to process osteogenic differentiation with appropriate mechanical and/or chemical stimuli. The present study described the successful culture of murine BMSCs under mechanical strain. BMSCs were subjected to 0%, 3%, 8%, 13%, and 18% cyclic tensile strain at 0.5 Hz for 8 hr/day for 3 days. The expression of osteogenic markers and mechanosensitive ion channels was evaluated with real-time reverse transcription-polymerase chain reaction (RT-PCR) and western blot. The expression of alkaline phosphatase (ALP) and matrix mineralization were evaluated with histochemical staining. To investigate the effects of mechanosensitive ion channel expression on cyclic tensile strain-induced osteogenic differentiation, the expression of osteogenic markers was evaluated with real-time RT-PCR in the cells without mechanosensitive ion channel expression. This study revealed a significant augment in osteogenic marker in BMSC strained at 8% compared to other treatments; therefore, an 8% strain was used for further investigations. The ALP expression and matrix mineralization were enhanced in osteogenic induced BMSCs subjected to 8% strain after 7 and 14 days, respectively. Under the same conditions, the osteogenic marker and mechanosensitive ion channel expression were significantly promoted. However, the loss function of mechanosensitive ion channels resulted in the inhibition of osteogenic marker expression. This study demonstrated that strain alone can successfully induce osteogenic differentiation in BMSCs and the expression of mechanosensitive ion channels was involved in the process. The current findings suggest that mechanical stretch could function as efficient stimuli to induce the osteogenic differentiation of BMSCs via the activation of mechanosensitive ion channels.


Assuntos
Células da Medula Óssea/metabolismo , Células da Medula Óssea/fisiologia , Diferenciação Celular/fisiologia , Canais Iônicos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Osteogênese/fisiologia , Fosfatase Alcalina/metabolismo , Animais , Biomarcadores/metabolismo , Células Cultivadas , Camundongos
13.
J Transl Med ; 19(1): 372, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34461927

RESUMO

BACKGROUND: Epidermal growth factor receptor (EGFR) and lanthionine synthetase C-like 2 (LanCL2) genes locate in the same amplicon, and co-amplification of EGFR and LANCL2 is frequent in glioblastoma. However, the prognostic value of LANCL2 and EGFR co-amplification, and their mRNA and protein expression in glioblastoma remain unclear yet. METHODS: This study analyzed the prognostic values of the copy number variations (CNVs), mRNA and protein expression of LANCL2 and EGFR in 575 glioblastoma patients in TCGA database and 100 glioblastoma patients in tumor banks of the Shenzhen Second People's Hospital and the Sun Yat-sen University Cancer Center. RESULTS: The amplification of LANCL2 or EGFR, and their co-amplification were frequent in glioblastoma of TCGA database and our tumor banks. A significant correlation was found between the CNVs of LANCL2 and EGFR (p < 0.001). CNVs of LANCL2 or EGFR were significantly correlated with IDH1/2 mutation but not MGMT promoter methylation. Multivariate analysis showed that LANCL2 amplification was significantly correlated with reduced overall survival (OS) in younger (< 60 years) glioblastoma patients of TCGA database (p = 0.043, HR = 1.657) and our tumor banks (p = 0.018, HR = 2.199). However, LANCL2 or EGFR amplification, and their co-amplification had no significant impact on OS in older (≥ 60 years) or IDH1/2-wild-type glioblastoma patients. mRNA and protein overexpression of LANCL2 and EGFR was also frequently found in glioblastoma. The mRNA expression rather than the protein expression of LANCL2 and EGFR was positively correlated (p < 0.001). However, mRNA or protein expression of EGFR and LANCL2 was not significantly correlated with OS of glioblastoma patients. The protein expression level of LANCL2, rather than EGFR, was elevated in relapsing glioblastoma, compared with newly diagnosed glioblastoma. In addition, the intracellular localization of LanCL2, not EGFR, was associated with the grade of gliomas. CONCLUSIONS: Taken together, amplification and mRNA overexpression of LANCL2 and EGFR, and their co-amplification and co-expression were frequent in glioblastoma patients. Our findings suggest that amplification of LANCL2 and EGFR were the independent diagnostic biomarkers for glioblastoma patients, and LANCL2 amplification was a significant prognostic factor for OS in younger glioblastoma patients.


Assuntos
Neoplasias Encefálicas , Receptores ErbB/genética , Glioblastoma , Proteínas de Membrana/genética , Proteínas de Ligação a Fosfato/genética , Idoso , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Variações do Número de Cópias de DNA/genética , Receptores ErbB/metabolismo , Glioblastoma/genética , Humanos , Mutação , Recidiva Local de Neoplasia , Prognóstico , RNA Mensageiro/genética
14.
J Org Chem ; 86(12): 7920-7927, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34038118

RESUMO

The Povarov reaction combines aromatic amines, aldehydes, and alkynes in a single step and is regarded as an annulative π-extension reaction of aromatic amines. In this study, the Povarov reaction was investigated as an efficient tool for the synthesis of aza-polycyclic aromatic hydrocarbons via multiple π-extensions. The double Povarov reaction of 1,4-diaminobenzene yielded the 4,7-phenanthroline derivative as the major product, regardless of the steric repulsion in the product. The site selectivity mainly depended on the HOMO distribution of the intermediate rather than the steric factor. Based on these insights, a 1,5,9-triazatriphenylene derivative was synthesized via a triple Povarov reaction. The structures of the synthesized compounds were unambiguously determined by single-crystal X-ray diffraction analysis. The triazatriphenylene derivative formed a smooth and stable thin film upon vacuum vapor deposition and served as a hole-blocking material in organic light-emitting diodes.

15.
Environ Sci Technol ; 55(19): 13286-13296, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34529405

RESUMO

The stack configuration in flow-electrode capacitive deionization (FCDI) has been verified to be an attractive and feasible strategy for scaling up the desalination process. However, challenges still exist when attempting to simultaneously improve the desalination scale and the cell configuration. Here, we describe a novel stack FCDI configuration (termed a gradient FCDI system) based on a membrane-current collector assembly, in which the charge neutralization enables the in situ regeneration of the flow electrodes in the single cycle operation, thereby realizing a considerable increase in the desalinating performance. By evaluating standardized metrics such as the salt rejection, productivity (P), average salt removal rate (ASRR), energy-normalized removed salt (ENRS), and TEE, the results indicated that the gradient FCDI system could be a performance-stable and energy-efficient alternative for scale-up desalination. Under optimal operating conditions (carbon content = 10 wt %, feed salinity = 3000 mg L-1, cell voltage = 1.2 V, and productivity = 56.7 L m-2 h-1), the robust desalination performance (ASRR = 1.07 µmol cm-2 min-1) and energy consumption (ENRS = 7.8 µmol J-1) of the FCDI system with a desalination unit number of four were verified at long-term operation. In summary, the stacked gradient FCDI system and its operation mode described here may be an innovative and promising strategy capable of enlarging the scale of desalination while realizing performance improvement and device simplification.


Assuntos
Purificação da Água , Adsorção , Eletrodos , Salinidade , Cloreto de Sódio
16.
Environ Sci Technol ; 55(11): 7634-7642, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33706511

RESUMO

Potassium periodate (PI, KIO4) was readily activated by Fe(II) under acidic conditions, resulting in the enhanced abatement of organic contaminants in 2 min, with the decay ratios of the selected pollutants even outnumbered those in the Fe(II)/peroxymonosulfate and Fe(II)/peroxydisulfate processes under identical conditions. Both 18O isotope labeling techniques using methyl phenyl sulfoxide (PMSO) as the substrate and X-ray absorption near-edge structure spectroscopy provided conclusive evidences for the generation of high-valent iron-oxo species (Fe(IV)) in the Fe(II)/PI process. Density functional theory calculations determined that the reaction of Fe(II) with PI followed the formation of a hydrogen bonding complex between Fe(H2O)62+ and IO4(H2O)-, ligand exchange, and oxygen atom transfer, consequently generating Fe(IV) species. More interestingly, the unexpected detection of 18O-labeled hydroxylated PMSO not only favored the simultaneous generation of ·OH but also demonstrated that ·OH was indirectly produced through the self-decay of Fe(IV) to form H2O2 and the subsequent Fenton reaction. In addition, IO4- was not transformed into the undesired iodine species (i.e., HOI, I2, and I3-) but was converted to nontoxic iodate (IO3-). This study proposed an efficient and environmental friendly process for the rapid removal of emerging contaminants and enriched the understandings on the evolution mechanism of ·OH in Fe(IV)-mediated processes.


Assuntos
Peróxido de Hidrogênio , Ferro , Compostos Ferrosos , Oxirredução , Ácido Periódico
17.
Phytother Res ; 35(6): 3390-3405, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33856743

RESUMO

Glioblastoma multiforme (GBM) is the most frequent, lethal, and aggressive tumor of the central nervous system in adults. In this study, we found for the first time that moschamindole (MCD), a rare phenolic amide with 8/6/6/5/5 rings, is a major bioactive constituent derived from Phragmites communis Trin (Poaceae) that exhibits a potential cytotoxic effect on both TMZ-resistant GBM cell lines and xenograft models. MCD-induced intrinsic apoptosis signals and mitochondrial dysfunction were confirmed by cell cycle arrest, caspase-3/7 activation, and membrane potential depolarization. Furthermore, investigations exploring the mechanism showed that MCD specifically inhibits Mia40-mediated oxidative folding of mitochondrial intermembrane space (IMS) proteins via PCR assay and immunoblot analysis. MCD relies on its positive charge to associate with mitochondrial oxidative respiration, thus blocking energy metabolism and inducing apoptosis. Overexpression and upregulation of Mia40 were proven to reverse MCD-induced apoptosis and were correlated with the chemoresistance of GBM in vitro and in vivo, respectively. Taken together, our study demonstrates that Mia40 is a potential target of the chemoresistance of glioblastoma and suggests that MCD might be a potential agent for the individualized treatment of chemoresistant GBM based on mitochondrial metabolic characteristics and Mia40 expression.


Assuntos
Apoptose/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Mitocôndrias/metabolismo , Animais , Glioblastoma/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Ann Diagn Pathol ; 53: 151762, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34102541

RESUMO

Paired box protein 8 (PAX8) is a transcription factor that is considered a relatively specific marker of carcinomas of the thyroid, kidney, and Müllerian/Wolffian duct derivatives. Unexpected PAX8 immunoreactivity has occasionally been reported in other tumors. The frequency of PAX8 expression in carcinomas of the biliary tract is not well studied. We evaluated the immunohistochemical expression of PAX8 in 73 cases of biliary tract carcinoma. We found that 28 of 73 (38%) biliary tract carcinomas had variable immunoreactivity for PAX8, assessed by a widely used polyclonal antibody (ProteinTech Group, Chicago, IL). This included 3 (4%) of cases with strong diffuse, and 14 (19%) of cases with strong focal staining. Strong PAX8 expression was more frequent in distal bile duct carcinomas than other biliary sites (p = 0.015), and showed a weak association with advanced T stage (T3-T4 versus T1-T2; p = 0.09). No correlation was observed between PAX8 positivity and age at diagnosis, gender, or lymph node metastasis. The 28 polyclonal PAX8-positive cases were largely negative for monoclonal PAX8 and PAX6 immunostains, with only rare tumor cells with weak immunoreactivity being present in a subset of cases. We show that a substantial fraction of biliary tract carcinomas exhibit immunoreactivity with a widely used polyclonal PAX8 antibody. Pathologists should be aware of this potential pitfall during the diagnostic workup of hepatobiliary lesions to avoid misdiagnosis as a metastasis from a PAX8-positive tumor.


Assuntos
Sistema Biliar/patologia , Biomarcadores Tumorais/metabolismo , Carcinoma/diagnóstico , Fator de Transcrição PAX8/metabolismo , Coloração e Rotulagem/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/metabolismo , Colangiocarcinoma/metabolismo , Colangiocarcinoma/secundário , Diagnóstico Diferencial , Erros de Diagnóstico/prevenção & controle , Feminino , Humanos , Imuno-Histoquímica/métodos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Estadiamento de Neoplasias/métodos , Patologistas/educação , Neoplasias Pélvicas/secundário , Estudos Retrospectivos , Coloração e Rotulagem/métodos
19.
Environ Sci Technol ; 54(24): 16231-16239, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33225681

RESUMO

Sulfate radical (SO4•-) is widely recognized as the predominant species generated from the cobalt(II)-activated peroxymonosulfate (PMS) process. However, in this study, it was surprisingly found that methyl phenyl sulfoxide (PMSO) was readily oxidized to the corresponding sulfone (PMSO2) with a transformation ratio of ∼100% under acidic conditions, which strongly implied the generation of high-valent cobalt-oxo species [Co(IV)] instead of SO4•- in the Co(II)/PMS process. Scavenging experiments using methanol (MeOH), tert-butyl alcohol, and dimethyl sulfoxide further suggested the negligible role of SO4•- and hydroxyl radical (•OH) but favored the generation of Co(IV). By employing 18O isotope-labeling technique, the formation of Co(IV) was conclusively verified and the oxygen atom exchange reaction between Co(IV) and H2O was revealed. Density functional theory calculation determined that the formation of Co(IV) was thermodynamically favorable than that of SO4•- and •OH in the Co(II)/PMS process. The generated Co(IV) species was indicated to be highly reactive due to the existence of oxo-wall and capable of oxidizing the organic pollutant that is rather recalcitrant to SO4•- attack, for example, nitrobenzene. Additionally, the degradation intermediates of sulfamethoxazole (SMX) in the Co(II)/PMS process under acidic conditions were identified to further understand the interaction between Co(IV) and the representative contaminant. The developed kinetic model successfully simulated PMSO loss, PMSO2 production, SMX degradation, and/or PMS decomposition under varying conditions, which further supported the proposed mechanism. This study might shed new light on the Co(II)/PMS process.


Assuntos
Cobalto , Peróxidos , Radical Hidroxila , Oxirredução
20.
Zhongguo Zhong Yao Za Zhi ; 45(9): 2138-2143, 2020 May.
Artigo em Zh | MEDLINE | ID: mdl-32495563

RESUMO

This study aims to establish an HPLC method for the simultaneous determination of 6 main components, including chlorogenic acid, 3,4-dicaffeoylquinic acid,3,5-dicaffeoylquinic acid,4,5-dicaffeoylquinic acid, pellitorine and neopellitorine B in Achil-leae Herba. HPLC analysis was performed on a Merck Purospher STAR RP-18 endcapped(4.6 mm×250 mm, 5 µm), with a mobile phase consisting of 0.05% phosphoric acid solution(A)-acetonitrile(B) at a flow rate of 1 mL·min~(-1)(0-7 min,12%-14% B;7-10 min,14%-17% B;10-25 min,17%-22% B;25-35 min,22%-35% B;35-51 min,35%-80% B;51-60 min,80%-90% B). The detection wavelength was 254 nm and the column temperature maintained at 30 ℃, and the injection volume was 5 µL. The standard curves revealed a good linear relationship. The contents of 6 components were 0.404%-2.116% for chlorogenic acid, 0.160%-0.892% for 3,4-dicaffeoylquinic acid, 0.608%-1.464% for 3,5-dicaffeoylquinic acid, 0.168%-0.868% for 4,5-dicaffeoylquinic acid, 0.122%-1.234% for pellitorine, 0.065%-0.312% for neopellitorine B, respectively. Both cluster and principal component analysis can distinguish the research data in anthesis and pre-anthesis by software Chempattern. There were obviously differences in the different harvest time. Therefore, attention should be paid to the harvesting time of the herb. The method can be used to determine the contents of six main components, and can provide reference for the improvement of quality standard of Achilleae Herba.


Assuntos
Medicamentos de Ervas Chinesas , Ácido Clorogênico , Cromatografia Líquida de Alta Pressão , Análise de Componente Principal
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