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1.
J Hazard Mater ; 469: 133956, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38460258

RESUMO

Polyhalogenated carbazoles (PHCZs), an emerging persistent halogenated organic pollutant, have been detected in the environment. However, our understanding of PHCZs in the ocean remains limited. In this study, 47 seawater samples (covering 50 - 4000 m) and sediment samples (49 surface and 3 cores) were collected to investigate the occurrence and spatial distribution patterns of carbazole and its halogenated derivants (CZDs) in the Western Pacific Ocean. In seawater, the detection frequencies of CZ (97.87%) and 3-CCZ (57.45%) were relatively high. In addition, the average concentration of ΣPHCZs in the upper water (< 150 m, 0.23 ± 0.21 ng/L) was significantly lower than that in the deep ocean (1000 - 4000 m, 0.65 ± 0.56 ng/L, P < 0.05), which may indicate the vertical transport of PHCZs in the marine environment. The concentration of ΣCZDs in surface sediment ranges from 0.46 to 6.48 ng/g (mean 1.54 ng/g), among which CZ and 36-CCZ were the predominant components. Results from sediment cores demonstrate a noteworthy negative correlation between the concentration of CZDs and depth, indicating the ongoing natural degradation process occurring in sediment cores over a long period. This study offers distinctive insights into the occurrence, composition, and vertical features of CZDs in oceanic environments.

2.
Med Phys ; 51(1): 601-611, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37831515

RESUMO

BACKGROUND: While the development of CT imaging technique has brought cognition of in vivo organs, the resolution of CT images and their static characteristics have gradually become barriers of microscopic tissue research. PURPOSE: Previous research used the finite element method to study the airflow and gas exchange in the alveolus and acinar to show the fate of inhaled aerosols and studied the diffusive, convective, and sedimentation mechanisms. Our study combines these techniques with CT scan simulation to study the mechanisms of respiratory movement and its imaging appearance. METHODS: We use 3D fluid-structure interaction simulation to study the movement of an ideal alveolus under regular and forced breathing situations and ill alveoli with different tissue elasticities. Additionally, we use the Monte Carlo algorithm within the OpenGATE platform to simulate the computational CT images of the dynamic process with different designated resolutions. The resolutions show the relationship between the kinematic model of the human alveolus and its imaging appearance. RESULTS: The results show that the alveolus and the wall thickness can be seen with an image resolution smaller than 15.6 µm. With ordinary CT resolution, the alveolus is expressed with four voxels. CONCLUSIONS: This is a preliminary study concerning the imaging appearance of the dynamic alveolus model. This technique will be used to study the imaging appearance of the dynamic bronchial tree and the lung lobe models in the future.


Assuntos
Pulmão , Alvéolos Pulmonares , Humanos , Pulmão/diagnóstico por imagem , Alvéolos Pulmonares/diagnóstico por imagem , Respiração , Aerossóis , Tomografia Computadorizada por Raios X , Simulação por Computador
3.
Adv Mater ; 36(1): e2308251, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37781857

RESUMO

Covalent organic frameworks (COFs) have shown great advantages as photocatalysts for hydrogen evolution. However, the effect of linkage geometry and type of linkage on the extent of π-electron conjugation in the plane of the framework and photocatalytic properties of COFs remains a significant challenge. Herein, two Kagome (kgm) topologic oligo(phenylenevinylene)-based COFs are designed and synthesized for boosting photocatalytic hydrogen evolution via a "two in one" strategy. Under visible light irradiation, COF-954 with 5 wt% Pt as cocatalyst exhibits high hydrogen evolution rate (HER) of 137.23 mmol g-1 h-1 , outperforming most reported COF-based photocatalysts. More importantly, even in natural seawater, COF-954 shows an average HER of 191.70 mmol g-1 h-1 under ultraviolet-visible (UV-vis) light irradiation. Additionally, the water-drainage experiments indoors and outdoors demonstrate that 25 and 8 mL hydrogen gas could be produced in 80 min under UV-vis light and natural sunlight, respectively, corresponding to a high HER of 167.41 and 53.57 mmol h-1 g-1 . This work not only demonstrates an effective design strategy toward highly efficient COF-based photocatalysts, but also shows the great potential of using the COF-based photocatalysts for photocatalytic hydrogen evolution.

4.
Front Pharmacol ; 14: 1254804, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074117

RESUMO

The demand for respiratory disease and dynamic breathing studies has continuously driven researchers to update the pulmonary bronchial tree's morphology model. This study aims to construct a bronchial tree morphology model efficiently and effectively with practical algorithms. We built a performance index system using failure branch rate, volume ratio, and coefficient of variation of terminal volumes to evaluate the model performance. We optimized the parameter settings and found the best options to build the morphology model, and we constructed a 14th-generation bronchial tree model with a decent performance index. The dimensions of our model closely matched published data from anatomic in vitro measurements. The proposed model is adjustable and computable and will be used in future dynamic breathing simulations and respiratory disease studies.

5.
Exp Cell Res ; 433(2): 113851, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37940066

RESUMO

BACKGROUND: Ovarian cancer has been a worldwide health burden for women and its progression is highly hypoxia-independent. Here, we investigated the exact mechanisms by which hypoxia contributes to the malignant progression of ovarian cancer. METHOD: MTT, transwell, colony formation, and scratch wound healing assays were carried out for cellular functions. The underlying mechanism by which hypoxia functions was explored by RNA-seq, enrichment analysis, western blotting, qRT-PCR, flow cytometry, ChIP, luciferase reporter, and ELISA. Finally, animal experiments including the xenograft model and tumor metastasis model were constructed to validate the role of SLC2A12 in vivo. RESULTS: Hypoxia treatment promoted the cell proliferation, mobility, and colony growth abilities of the two ovarian cancer cell lines HO-8910 and A2780. RNA-seq and enrichment analysis showed that SLC2A12 was hyper-expressed under hypoxia condition and it may be related to glutathione and lipid metabolism. Besides, the expression of SLC2A12 was negatively correlated with overall survival. Hypoxia suppressed ferroptosis by SLC2A12 because silencing SLC2A12 declined the cell viability of HO-8910 and A2780 cells under hypoxia conditions, while the ferroptosis inhibitor ferrostatin-1 (Fer-1) breached that result and upregulated the expression of glutathione peroxidase 4 (GPX4). Moreover, hypoxia increased the expression of hypoxia inducible factor 1 A (HIF-1A), and the accumulated HIF-1A binds to hypoxia inducible factor 1 B (HIF1B) to form HIF-1 complex, then promoted the binding of hypoxic response elements (HRE) to SLC2A12 promoter by HIF-1/HRE signal. Subsequently, SLC2A12 regulated glutathione metabolism and in turn inhibited ferroptosis. The animal experiments indicated that silencing SLC2A12 could significantly inhibit tumor growth and metastasis in vivo. CONCLUSION: Hypoxia promoted ovarian cancer progression by upregulating SLC2A12 and then regulating glutathione metabolism to inhibit ferroptosis.


Assuntos
Ferroptose , Proteínas Facilitadoras de Transporte de Glucose , Neoplasias Ovarianas , Animais , Feminino , Humanos , Linhagem Celular Tumoral , Ferroptose/genética , Glutationa , Hipóxia , Fator 1 Induzível por Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias Ovarianas/patologia , Proteínas Facilitadoras de Transporte de Glucose/genética , Proteínas Facilitadoras de Transporte de Glucose/metabolismo
6.
Chem Commun (Camb) ; 59(79): 11863-11866, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37721474

RESUMO

In this work, one-dimensional TiO2 nanotube arrays are coupled with a covalent organic framework (COF) thin film with a controlled thickness to form a three-dimensional heterojunction, which exhibits a 3.3-fold higher hydrogen evolution rate than that of TiO2, and becomes active for CO2 conversion, compared to the bare COF. Such high activity results from the large difference in Fermi levels forming an internal electric field at the interface.

7.
Artigo em Inglês | MEDLINE | ID: mdl-37549732

RESUMO

OBJECTIVE: To investigate the prevalence of a tet(A) gene variant and its role in developing high-level tigecycline resistance among carbapenem-resistant Klebsiella pneumoniae (CRKP) clinical isolates. METHODS: The mechanism of high-level tigecycline resistance in CRKP mediated by a tet(A) variant was explored by induction experiments, antimicrobial susceptibility testing, whole-genome sequencing and bioinformatics analysis. The amplification and overexpression of the tet(A) variant were measured by the determination of sequencing depth, gene copy numbers, and qRT-PCR. RESULTS: A high rate (62.1%, 998/1607) of tet(A) variant carriage was observed among 1607 CRKP clinical isolates from Henan Province, China. High-level tigecycline resistance could rapidly develop by the amplification of the tet(A) variant in these isolates. The analysis of the raw sequencing data and the plasmid mapping depth revealed that the ΔtnpA homologous sequence of Tn1721 supports the amplification of the region that harbours the tet(A) variant by forming a large number of repeat arrays through translocatable units (TUs). Moreover, the epidemiological analysis of tet(A) variant-carrying structures among 1607 clinical CRKPs showed that the TU structure is widely present. CONCLUSION: The presence of a tigecycline resistance-mediating tet(A) variant in CRKP clinical isolates represents a greater health concern than initially thought and should be monitored consistently.

8.
Mater Horiz ; 10(10): 4183-4191, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37534697

RESUMO

Strong and ductile adhesives often undergo both interfacial and cohesive failure during the debonding process. Herein, we report a rare self-reinforcing polyurethane adhesive that shows the different phenomenon of only interfacial failure yet still exhibiting superior adhesive strength and toughness. It is synthesized by designing a hanging adhesive moiety, hierarchical H-bond moieties, and a crystallizable soft segment into one macromolecular polyurethane. The former hanging adhesive moiety allows the hot-melt adhesive to effectively associate with the target substrate, providing sufficient adhesion energy; the latter hierarchical H-bond moieties and a crystallizable soft segment cooperate to enable the adhesive to undergo large lap-shear deformations through sacrificing weak bonds and mechano-responsive strength through the fundamental mechanism of strain-induced crystallization. As a result, this polyurethane adhesive can keep itself intact during the debonding process while still withstanding a high lap-shear strength and dissipating tremendous stress energy. Its adhesive strength and work of debonding are as high as 11.37 MPa and 10.32 kN m-1, respectively, outperforming most reported tough adhesives. This self-reinforcing adhesive is regarded as a new member of the family of strong and ductile adhesives, which will provide innovative chemical and structural inspirations for future conveniently detachable yet high-performance adhesives.

9.
Angew Chem Int Ed Engl ; 62(38): e202307962, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37547954

RESUMO

To exploit the potential of our newly developed three-dimensional (3D) dimerized acceptors, a series of chlorinated 3D acceptors (namely CH8-3/4/5) were reported by precisely tuning the position of chlorine (Cl) atom. The introduction of Cl atom in central unit affects the molecular conformation. Whereas, by replacing fluorinated terminal groups (CH8-3) with chlorinated terminal groups (CH8-4 and CH8-5), the red-shift absorption and enhanced crystallization are achieved. Benefiting from these, all devices received promising power conversion efficiencies (PCEs) over 16 % as well as decent thermal/photo-stabilities. Among them, PM6:CH8-4 based device yielded a best PCE of 17.58 %. Besides, the 3D merits with multi alkyl chains enable their versatile processability during the device preparation. Impressive PCEs of 17.27 % and 16.23 % could be achieved for non-halogen solvent processable devices prepared in glovebox and ambient, respectively. 2.88 cm2 modules also obtained PCEs over 13 % via spin-coating and blade-coating methods, respectively. These results are among the best performance of dimerized acceptors. The decent performance of CH8-4 on small-area devices, modules and non-halogen solvent-processed devices highlights the versatile processing capability of our 3D acceptors, as well as their potential applications in the future.

10.
J Am Chem Soc ; 145(25): 13537-13541, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37338385

RESUMO

Three-dimensional covalent organic frameworks (3D COFs) have been of great interest due to their inherent numerous open sites and pore confinement effect. However, it has remained challenging to build 3D frameworks via interdigitation (also known as inclined interpenetration) by generating an entangled network formed by multiple 2D layers inclined with respect to each other. Herein, we report the first case of constructing a 3D COF, termed COF-904, through interdigitating 2D hcb nets, which was formed via [3+2] imine condensation reactions by the use of 1,3,5-triformylbenzene and 2,3,5,6-tetramethyl-1,4-phenylenediamine. The single-crystal structure of COF-904 is solved, and the locations of all non-hydrogen atoms are determined by 3D electron diffraction with a resolution up to 0.8 Å. These results not only broaden the strategy for achieving 3D COFs via interdigitation but also demonstrate that structurally complex extended frameworks can arise from simple molecules.

11.
Angew Chem Int Ed Engl ; 62(30): e202304611, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37227370

RESUMO

Covalent organic frameworks (COFs) have gained significant attention as key photocatalysts for efficient solar light conversion into hydrogen production. Unfortunately, the harsh synthetic conditions and intricate growth process required to obtain highly crystalline COFs greatly hinder their practical application. Herein, we report a simple strategy for the efficient crystallization of 2D COFs based on the intermediate formation of hexagonal macrocycles. Mechanistic investigation suggests that the use of 2,4,6-triformyl resorcinol (TFR) as the asymmetrical aldehyde build block allows the equilibration between irreversible enol-to-keto tautomerization and dynamic imine bonds to produce the hexagonal ß-ketoenamine-linked macrocycles, the formation of which could provide COFs with high crystallinity in half hour. We show that COF-935 with 3 wt % Pt as cocatalyst exhibit a high hydrogen evolution rate of 67.55 mmol g-1 h-1 for water splitting when exposed to visible light. More importantly, COF-935 exhibits an average hydrogen evolution rate of 19.80 mmol g-1 h-1 even at a low loading of only 0.1 wt % Pt, which is a significant breakthrough in this field. This strategy would provide valuable insights into the design of highly crystalline COFs as efficient organic semiconductor photocatalysts.

12.
J Interv Cardiol ; 2023: 8873404, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37064642

RESUMO

Aim: Steam pop (SP) during radiofrequency catheter ablation (RFCA) for pulmonary vein isolation (PVI) may cause cardiac perforation, which may require drainage and emergent thoracotomy or even lead to death. Data investigating the timely detection of the occurrence of "silent" or "nonaudible" SP events are limited. Methods and Results: A total of 516 consecutive atrial fibrillation (AF) patients who underwent index PVI were included in this retrospective observational study. The duration, power, impedance, temperature, and contact force (CF) of RFCA were continually monitored and recorded throughout the procedure. A total of 15 (2.9%) audible SP events occurred in 14 patients; 2 of the patients developed pericardial tamponade, 1 patient underwent drainage, and 1 patient underwent emergent thoracotomy. The time from RFCA initiation to the occurrence of audible SP was 19.4 ± 6.9 s. Abrupt temperature change occurred in 13 (86.7%) of the 15 SP events, of which 8 (53.3%) exhibited an abrupt temperature rise of 2.3 ± 1.0°C, 5 (33.3%) exhibited an abrupt temperature drop of 2.3 ± 1.3°C, and 2 (13.3%) exhibited no discernible temperature change. Conclusions: In conclusion, simultaneously recorded spike potentials and abrupt impedance rise with concomitant temperature and/or CF change could be a feasible method for the timely detection of the occurrence of audible, "silent," or "nonaudible" SP events, particularly in regions where the risk of perforation may be of concern.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Humanos , Temperatura , Vapor , Impedância Elétrica , Potenciais de Ação , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Veias Pulmonares/cirurgia , Resultado do Tratamento
13.
Int J Gynaecol Obstet ; 160(2): 571-578, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35871356

RESUMO

OBJECTIVE: To address the value of visual inspection where HPV-based screening is not yet available, we evaluated the real-world effectiveness of visual inspection with acetic acid (VIA) and with Lugol's iodine (VILI) as a primary screening method for cervical cancer in rural China. METHODS: A total of 206 133 women aged 30-59 years received two rounds of VIA/VILI screening for cervical cancer in 2006-2010. Women with positive screening results underwent colposcopy and direct biopsy, and were treated if cervical intraepithelial neoplasia grade 2 or worse (CIN2+) was diagnosed. Clinical effectiveness of VIA/VILI was evaluated by process and outcome measures. RESULTS: The VIA/VILI positivity rate, biopsy rate and detection rate of CIN2+ in the second round were significantly lower than in the first round. The 2-year cumulative detection rate of CIN2+ varied from 0.53% to 0.90% among the four cohorts initiated in 2006, 2007, 2008, and 2009. The first round of screening detected 60%-83% of CIN2, 70%-86% of CIN3, and 88%-100% of cervical cancer. Over 92% of CIN2+ were found at the early stage. CONCLUSION: Multiple rounds of visual inspection with continuous training and quality assurance could act as a temporary substitutional screening method for cervical cancer in resource-restricted settings.


Assuntos
Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/diagnóstico , Ácido Acético , Detecção Precoce de Câncer/métodos , Displasia do Colo do Útero/diagnóstico , Iodetos , Programas de Rastreamento/métodos
14.
Angew Chem Int Ed Engl ; 62(5): e202216073, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36450661

RESUMO

Imine-linked covalent organic frameworks (COFs) have been extensively studied in photocatalysis because of their easy synthesis and excellent crystallinity. The effect of imine-bond orientation on the photocatalytic properties of COFs, however, is still rarely studied. Herein, we report two novel COFs with different orientations of imine bonds using oligo(phenylenevinylene) moieties. The COFs showed similar structures but great differences in their photoelectric properties. COF-932 demonstrated a superior hydrogen evolution performance compared to COF-923 when triethanolamine was used as the sacrificial agent. Interestingly, the use of ascorbic acid led to the protonation of the COFs, further altering the direction of electron transfer. The photocatalytic performances were increased to 23.4 and 0.73 mmol g-1 h-1 for protonated COF-923 and COF-932, respectively. This study provides a clear strategy for the design of imine-linked COF-based photocatalysts and advances the development of COFs.

15.
CNS Neurosci Ther ; 29(1): 378-389, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36353753

RESUMO

AIMS: The claustrum has long been regarded as a vital center for conscious control. Electrical stimulation or damage to the claustrum can result in decreased awareness or loss of consciousness, suggesting that the claustrum may be a target for the action of general anesthetics. This study aimed to determine the role of the claustrum in propofol anesthesia. METHODS: We first applied a fiber photometry calcium signal recording system to record the claustral neuronal activity during the entire process of propofol anesthesia. Chemogenetic activation of claustral neurones was then performed to verify their role in anesthesia. Finally, muscimol (GABAa receptor agonist) and gabazine (GABAa receptor antagonist) were microinjected into the claustrum to determine whether their GABAa receptors were involved in modulating propofol anesthesia. EEG and behavioral indicators, such as anesthetic sensitivity and efficacy, were recorded and analyzed. RESULTS: An evident anesthesia-related change in claustrum neuronal activity was suppressed during propofol-induced unconsciousness and restored following recovery from anesthesia. Chemogenetic activation of claustrum neurons results in attenuated propofol sensitivity, a shorter anesthesia duration, and an EEG shift toward wakefulness. Manipulation of GABAa receptors in the claustrum showed bidirectional control of propofol sensitivity, as activation decreases anesthesia efficiency while inactivation augments it. Additionally, inhibiting claustrum GABAa receptors increases cortical EEG slow waves. CONCLUSIONS: Claustrum neurones and their GABAa receptors are implicated in the modulation of propofol anesthesia in both behavioral and EEG assessments. Our findings create scope to reveal the brain targets of anesthetic action further and add to the existing evidence on the consciousness-modulating role of the claustrum.


Assuntos
Anestesia , Anestésicos Gerais , Claustrum , Propofol , Propofol/farmacologia , Receptores de GABA-A , Anestésicos Gerais/farmacologia , Eletroencefalografia
16.
Front Neurol ; 13: 889090, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36408497

RESUMO

Ischemic stroke has become a severe disease endangering human life. However, few studies have analyzed the radiomics features that are of great clinical significance for the diagnosis, treatment, and prognosis of patients with ischemic stroke. Due to sufficient cerebral blood flow information in dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI) images, this study aims to find the critical features hidden in DSC-PWI images to characterize hypoperfusion areas (HA) and normal areas (NA). This study retrospectively analyzed 80 DSC-PWI data of 56 patients with ischemic stroke from 2013 to 2016. For exploring features in HA and NA,13 feature sets (F method ) were obtained from different feature selection algorithms. Furthermore, these 13 F method were validated in identifying HA and NA and distinguishing the proportion of ischemic lesions in brain tissue. In identifying HA and NA, the composite score (CS) of the 13 F method ranged from 0.624 to 0.925. F Lasso in the 13 F method achieved the best performance with mAcc of 0.958, mPre of 0.96, mAuc of 0.982, mF1 of 0.959, and mRecall of 0.96. As to classifying the proportion of the ischemic region, the best CS was 0.786, with Acc of 0.888 and Pre of 0.863. The classification ability was relatively stable when the reference threshold (RT) was <0.25. Otherwise, when RT was >0.25, the performance will gradually decrease as its increases. These results showed that radiomics features extracted from the Lasso algorithms could accurately reflect cerebral blood flow changes and classify HA and NA. Besides, In the event of ischemic stroke, the ability of radiomics features to distinguish the proportion of ischemic areas needs to be improved. Further research should be conducted on feature engineering, model optimization, and the universality of the algorithms in the future.

17.
Diagnostics (Basel) ; 12(7)2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35885568

RESUMO

BACKGROUND: Accurate outcome prediction is of great clinical significance in customizing personalized treatment plans, reducing the situation of poor recovery, and objectively and accurately evaluating the treatment effect. This study intended to evaluate the performance of clinical text information (CTI), radiomics features, and survival features (SurvF) for predicting functional outcomes of patients with ischemic stroke. METHODS: SurvF was constructed based on CTI and mRS radiomics features (mRSRF) to improve the prediction of the functional outcome in 3 months (90-day mRS). Ten machine learning models predicted functional outcomes in three situations (2-category, 4-category, and 7-category) using seven feature groups constructed by CTI, mRSRF, and SurvF. RESULTS: For 2-category, ALL (CTI + mRSRF+ SurvF) performed best, with an mAUC of 0.884, mAcc of 0.864, mPre of 0.877, mF1 of 0.86, and mRecall of 0.864. For 4-category, ALL also achieved the best mAuc of 0.787, while CTI + SurvF achieved the best score with mAcc = 0.611, mPre = 0.622, mF1 = 0.595, and mRe-call = 0.611. For 7-category, CTI + SurvF performed best, with an mAuc of 0.788, mPre of 0.519, mAcc of 0.529, mF1 of 0.495, and mRecall of 0.47. CONCLUSIONS: The above results indicate that mRSRF + CTI can accurately predict functional outcomes in ischemic stroke patients with proper machine learning models. Moreover, combining SurvF will improve the prediction effect compared with the original features. However, limited by the small sample size, further validation on larger and more varied datasets is necessary.

18.
ACS Macro Lett ; 11(4): 447-451, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35575316

RESUMO

The Diels-Alder reaction is striking as a prominent synthetic tool for the rapid construction of complex molecular frameworks, but the synthesis of porous organic polymers (POPs) via the Diels-Alder reaction is rare. Herein, we report the solvothermal synthesis of a new type of POPs (DA-POPs) via the furan/alkynyl Diels-Alder reaction. These polymers show favorable porous properties and high specific surface areas (up to 1041 m2·g-1). Meanwhile, the high porosity in conjuction of ether bridges in the DA-POPs enable a fine adsorption performance for the removal of Cr(VI) from aqueous solutions.


Assuntos
Cromo , Polímeros , Reação de Cicloadição , Porosidade , Água
19.
Technol Health Care ; 30(S1): 71-80, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35124585

RESUMO

BACKGROUND: The etiology of polycystic ovary syndrome (PCOS) remains unclear with highly heterogeneous clinical manifestations, recently growing evidence revealing genetic variants play a crucial part in its pathogenesis. OBJECTIVE: This study aimed to examine the correlation between SNPs in miRNA-135a's binding site of targeted gene IRS2 and clinical manifestations of PCOS in Chinese females. METHOD: A total of 126 Chinese women with PCOS and 109 healthy women were enrolled, divided into 4 groups based on different clinical features of hyperandrogenemia (HA), insulin resistance (IR), polycystic ovary morphology (PCOM) and obesity. We analyzed 2 single nucleotide polymorphisms (SNPs) of the IRS2 gene (rs2289046 and rs1865434) and clinical features' laboratory measurements such as sex hormone, fasting plasma glucose (FPG), fasting plasma insulin (FINS). RESULTS: Located in miRNA-135a binding site of IRS2 gene, the rs2289046's triple genotypes distribution showed a significant difference between PCOS/control group and PCOM/non-PCOM group (P< 0.05) while the rs1865434's triple genotype distribution showed a significant difference between obesity/non-obesity group (P< 0.05). CONCLUSION: The results revealed the two SNPs as rs2289046 and rs1865434 in the IRS-2 binding region of miRNA-135a have correlations with the clinical features of PCOS in Chinese population.


Assuntos
MicroRNAs , Síndrome do Ovário Policístico , Sítios de Ligação , Estudos de Casos e Controles , China , Feminino , Predisposição Genética para Doença , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , MicroRNAs/genética , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo , Polimorfismo de Nucleotídeo Único
20.
Med Sci Monit ; 28: e934660, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35153292

RESUMO

BACKGROUND Fundamental and clinical interest in mesenchymal stem cells (MSCs) has risen dramatically over the past 3 decades. The immunomodulatory and differentiation abilities are the main mechanisms in vitro and in vivo. However, increasing evidence casts doubt on the stemness and immunogenicity of MSCs. MATERIAL AND METHODS We conducted a high-throughput 10x RNA sequencing and Smart-seq2 scRNA-seq analysis to reveal gene expression of Wharton jelly MSCs (WJ-MSCs) at a single-cell level. Multipotent differentiation, subpopulations, marker genes, human leucocyte antigen (HLA) gene expression, and cell cluster trajectory analysis were evaluated. RESULTS The WJ-MSCs had considerable heterogeneity between cells in terms of gene expression. They highly, partially, and hardly expressed genes related to mesodermal differentiation, endodermal differentiation, and ectodermal differentiation, respectively. Some cells seem to be bipotent or unipotent stem cells. Further, Monocle and cell cluster trajectory analysis demonstrated that 1 of the 3 divided clusters performed as stem cells, accounting for 12.6% of the population. The marker genes for a stem cell cluster were CRIM1, GLS, PLOD2, NEXN, ACTR2, FN1, MBNL1, LMOD1, COL3A1, NCL, SEC62, EPRS, COL5A2, COL8A1, and VCAN. In addition, the MSCs also highly, partially, and hardly expressed HLA-I antigen genes, HLA-II genes, and the HLA-G gene, respectively, indicating that MSCs probably have immunogenicity. A Kyoto Encyclopedia of Genes and Genomes pathway analysis of the 3 clusters demonstrated that they were mainly connected with viral infectious diseases, cancer, and endocrine and metabolic disorders. The most expressed transcription factors were zf-C2H2, HMG/HMGY, and Homeobox. CONCLUSIONS We found that only a subpopulation of WJ-MSCs are real stem cells and WJ-MSCs probably do not have immune privilege.


Assuntos
Privilégio Imunológico , Células-Tronco Mesenquimais/citologia , RNA/genética , Cordão Umbilical/citologia , Geleia de Wharton/citologia , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/imunologia , Análise de Sequência de RNA , Fatores de Transcrição , Cordão Umbilical/imunologia , Geleia de Wharton/imunologia , Geleia de Wharton/metabolismo
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