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1.
J Int Med Res ; 52(4): 3000605241240993, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38606733

RESUMEN

OBJECTIVE: We developed a simple, rapid predictive model to evaluate the prognosis of older patients with lung adenocarcinoma. METHODS: Demographic characteristics and clinical information of patients with lung adenocarcinoma aged ≥60 years were retrospectively analyzed using Surveillance, Epidemiology, and End Results (SEER) data. We built nomograms of overall survival and cancer-specific survival using Cox single-factor and multi-factor regression. We used the C-index, calibration curve, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA) to evaluate performance of the nomograms. RESULTS: We included 14,117 patients, divided into a training set and validation set. We used the chi-square test to compare baseline data between groups and found no significant differences. We used Cox regression analysis to screen out independent prognostic factors affecting survival time and used these factors to construct the nomogram. The ROC curve, calibration curve, C-index, and DCA curve were used to verify the model. The final results showed that our predictive model had good predictive ability, and showed better predictive ability compared with tumor-node-metastasis (TNM) staging. We also achieved good results using data of our center for external verification. CONCLUSION: The present nomogram could accurately predict prognosis in older patients with lung adenocarcinoma.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Anciano , Estudios Retrospectivos , Nomogramas , Calibración , Pronóstico , Estadificación de Neoplasias
2.
Angew Chem Int Ed Engl ; : e202403660, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38465907

RESUMEN

Luminescent organic radicals, especially those with photoactivated circularly polarized luminescence (CPL) features, hold great significance for cutting-edge optoelectronic applications, but their development still remains a challenge. In this study, we propose a novel strategy to achieve photoactivated CPL radicals by bonding two phosphine centers within an axial chiral system, yielding a compound of R/S-5,5-bis(diphenylphosphino)-4,4'-bibenzo[d][1,3]dioxole (R/S-BDP). The photoactivated R/S-BDP molecules in polymer matrix display a robust quantum yield of 19.8 % and a dissymmetry factor (glum) of 1.2×10-4, marking this work as the first example of photoactivated CPL radicals. Furthermore, the glum is improved to 1.0×10-2 by using a liquid crystal as host. Experimental and theoretical analyses reveal that R/S-BDP molecules, endowed with double phosphine cores in axial chirality, offer a direct way for intramolecular electron transfer upon photoirradiation. This leads to the generation of radical ionic pairs, which subsequently trigger the donor-acceptor arrangement through intermolecular electron transfer, thereby resulting in stable radical emission. The extended photoactivated BDP-F exhibits a remarkably high quantum efficiency of 57.8%. Ultimately, the distinctive photo-responsive CPL radical luminescence has been successfully used for information displays and anti-counterfeiting.

3.
Animal Model Exp Med ; 7(1): 48-55, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38372486

RESUMEN

BACKGROUND: The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis. However, the low incidence and unpredictability of symptoms are caused by numerous complex variant types of the circle. Additionally, the lack of an evaluation system for the cerebral ischemia/reperfusion (I/R) model of gerbils has shackled the application of this model. METHODS: We created a symptom-oriented principle and detailed neurobehavioral scoring criteria. At different time points of reperfusion, we analyzed the alteration in locomotion by rotarod test and grip force score, infarct volume by triphenyltetrazolium chloride (TTC) staining, neuron loss using Nissl staining, and histological characteristics using hematoxylin-eosin (H&E) straining. RESULTS: With a successful model rate of 56%, 32 of the 57 gerbils operated by our method harbored typical features of cerebral I/R injury, and the mortality rate in the male gerbils was significantly higher than that in the female gerbils. The successfully prepared I/R gerbils demonstrated a significant reduction in motility and grip strength at 1 day after reperfusion; formed obvious infarction; exhibited typical pathological features, such as tissue edema, neuronal atrophy and death, and vacuolated structures; and were partially recovered with the extension of reperfusion time. CONCLUSION: This study developed a new method for the unilateral common carotid artery ligation I/R model of gerbil and established a standardized evaluation system for this model, which could provide a new cerebral I/R model of gerbils with more practical applications.


Asunto(s)
Isquemia Encefálica , Animales , Masculino , Femenino , Gerbillinae/fisiología , Isquemia Encefálica/patología , Infarto Cerebral/patología , Neuronas/patología , Reperfusión
4.
Phys Chem Chem Phys ; 26(3): 2395-2401, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38168797

RESUMEN

Two novel B-embedded disulfide-bridged π-conjugated compounds (BS-CZ and BS-N) bearing different electron donor groups (phenyl carbazole and triphenylamine) have been prepared and show different optical mechanisms. The compound BS-CZ exhibits significant multiple resonance thermal activation delayed fluorescence (MR-TADF) properties with a small singlet-triplet energy gap (ΔEST = 0.16 eV) and a narrow half-peak full width (FWHM = 33 nm), while the compound BS-N shows traditional fluorescence luminescence (FL) characteristics with a larger ΔEST (0.28 eV) and FWHM (57 nm). Time-dependent density functional theory (TD-DFT) calculations show that the lowest excited singlet state (S1) of the compound BS-CZ exhibits local excited (LE) state characteristics, while the charge transfer (CT) state characteristics can be found in S1 of the compound BS-N. Considering good optical performance, the compound BS-CZ is used as an emitting layer of the organic light-emitting diode device and achieved saturated blue emission (473 nm) with a narrow FWHM (39 nm), and CIE color coordinates of (0.12, 0.21). This work provides an important strategy for the optical mechanism regulation and photoelectric applications of B-embedded disulfide-bridged π-conjugated molecules.

5.
Redox Biol ; 69: 103002, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38142583

RESUMEN

Lipid peroxidation and redox imbalance are hallmarks of ferroptosis, an iron-dependent form of cell death. Growing evidence suggests that dysregulation in glycolipid metabolism and iron homeostasis substantially contribute to the development of hepatocellular carcinoma (HCC). However, there is still a lack of comprehensive understanding regarding the specific transcription factors that are capable of coordinating glycolipid and redox homeostasis to initiate the onset of ferroptosis. We discovered that overexpression of SOX8 leads to impaired mitochondria integrate, increased oxidative stress, and enhanced lipid peroxidation. These effects can be attributed to the inhibitory impact of SOX8 on de novo lipogenesis, glycolysis, the tricarboxylic acid cycle (TCA), and the pentose phosphate pathway (PPP). Additionally, upregulation of SOX8 results in reduced synthesis of NADPH, disturbance of redox homeostasis, disruption of mitochondrial structure, and impairment of the electron transport chain. Furthermore, the overexpression of SOX8 enhances the process of ferroptosis by upregulating the expression of genes associated with ferroptosis and elevating intracellular levels of ferrous ion. Importantly, the overexpressing of SOX8 has been observed to inhibit the proliferation of HCC in immunodeficient animal models. In conclusion, the findings suggest that SOX8 has the ability to alter glycolipid and iron metabolism of HCC cells, hence triggering the process of ferroptosis. The results of our study present a novel strategy for targeting ferroptosis in the therapy of HCC.


Asunto(s)
Carcinoma Hepatocelular , Ferroptosis , Neoplasias Hepáticas , Animales , Carcinoma Hepatocelular/genética , Ferroptosis/genética , Neoplasias Hepáticas/genética , Glucolípidos , Hierro
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 308: 123774, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38141503

RESUMEN

Carbonaceous fluid within mineral-hosted inclusions provides important information for carbon cycle in deep Earth. In addition to CH4 and CO2, heavy hydrocarbons (e.g., C2H6 and C3H8) are frequently observed in carbonaceous fluid inclusions (i.e, wet gas inclusions with C1/∑Ci < 0.95). However, determination of the composition of such complex volatiles is difficult based on traditional microthermometric measurements. Here we carried out experimental calibrations on Raman spectroscopic measurements of the pressure (P) and composition of the CH4 ± C2H6 ± C3H8 ± H2S system at room temperature and 0.1-130 MPa. We confirmed that the C-H symmetric stretching vibration band of CH4 [ν1(CH4), ∼2917 cm-1] shifted to lower wavenumber with rising pressure, thus the P-ν1(CH4) relationship could be applied to calculate the pressure of wet gas. It should be noted that the presence of C2+ and/or H2S will shift the [ν1(CH4)] to lower wavenumber at constant pressure (with the order of C3H8 ≥ H2S > C2H6). Obviously, the P-ν1(CH4) relationship derived from pure CH4 system could not be simply applied to wet gas inclusion, otherwise the pressure would be overestimated. To avoid the overlap of the C-H vibrations of CH4, C2H6 and C3H8, the peak areas and peak heights of the overtone vibration of CH4 [2ν4(CH4), ∼2580 cm-1], C-C symmetric stretching vibrations of C2H6 [ν3(C2H6), ∼995 cm-1] and C3H8 [ν8(C3H8), ∼868 cm-1], and S-H symmetric stretching vibration of H2S [ν1(H2S), ∼2612 cm-1] were fitted using Gaussian + Lorentz functions. The obtained peak areas and peak heights were then used to calculate the Raman quantification factors (F factor and G factor, respectively) of C2H6, C3H8 and H2S relative to CH4, respectively. Both the F factor and G factor increased with rising pressure, whereas the FC2H6, FC3H8 and GH2S kept nearly constant at ∼5.69, 6.39 and 153.8, respectively in high pressure gas mixtures (e.g., >30 MPa). Therefore, for inclusions with higher internal pressure, the molar ratio of CH4, C2H6, C3H8 and H2S could be determined by the aforementioned F and G factors. This method was applied to the calcite-hosted single-phase gas inclusions in the Upper Permian Changxing Formation carbonate reservoir from the eastern Sichuan Basin (South China). Our results indicated that the trapping pressure would be obviously overestimated if the presence of heavy hydrocarbons was not taken into account.

7.
Nat Commun ; 14(1): 8112, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38062051

RESUMEN

Prodrug photolysis enables spatiotemporal control of drug release at the desired lesions. For photoactivated therapy, near-infrared (NIR) light is preferable due to its deep tissue penetration and low phototoxicity. However, most of the photocleavable groups cannot be directly activated by NIR light. Here, we report a upconversion-like process via only one step of energy transfer for NIR light-triggered prodrug photolysis. We utilize a photosensitizer (PS) that can be activated via singlet-triplet (S-T) absorption and achieve photolysis of boron-dipyrromethene (BODIPY)-based prodrugs via triplet-triplet energy transfer. Using the strategy, NIR light can achieve green light-responsive photolysis with a single-photon process. A wide range of drugs and bioactive molecules are designed and demonstrated to be released under low-irradiance NIR light (100 mW/cm2, 5 min) with high yields (up to 87%). Moreover, a micellar nanosystem encapsulating both PS and prodrug is developed to demonstrate the practicality of our strategy in normoxia aqueous environment for cancer therapy. This study may advance the development of photocleavable prodrugs and photoresponsive drug delivery systems for photo-activated therapy.


Asunto(s)
Profármacos , Fotólisis , Sistemas de Liberación de Medicamentos , Fármacos Fotosensibilizantes/uso terapéutico , Transferencia de Energía
8.
J Int Med Res ; 51(11): 3000605231208923, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37976276

RESUMEN

Anlotinib is a tyrosine kinase inhibitor that targets the vascular endothelial growth factor receptor for the treatment of lung cancer. Pneumothorax is a rare complication of anlotinib treatment. Here, the case of a male patient in his early seventies, with lung cancer combined with emphysema, who developed a pneumothorax during treatment with anlotinib, is described. The patient was admitted to hospital mainly for dyspnoea and was diagnosed with pneumothorax after digital radiography of the chest. The patient's symptoms improved significantly after closed chest drainage, and a repeat chest digital radiography showed a more resolved pneumothorax. The patient had no previous history of pneumothorax. After discontinuation of anlotinib, the latest follow-up chest computed tomography assessment in August 2023 showed no recurrence of pneumothorax, thus, the pneumothorax is presumed to have been associated with anlotinib in this patient. In addition, the authors speculate that emphysema may be a cause of pneumothorax in patients with lung cancer receiving anlotinib treatment. Therefore, clinicians should be alert to the risk of pneumothorax occurrence in patients with emphysema combined with lung cancer who are treated with anlotinib.


Asunto(s)
Enfisema , Neoplasias Pulmonares , Neumotórax , Humanos , Masculino , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/tratamiento farmacológico , Neumotórax/inducido químicamente , Neumotórax/diagnóstico por imagen , Factor A de Crecimiento Endotelial Vascular
9.
Fish Shellfish Immunol ; 142: 109118, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37774901

RESUMEN

Species in Triplophysa display strong adaptability to the extreme environment of the plateau, thus offering an ideal model to study the molecular mechanism of fish adaptation to environmental stress. In the present study, we conducted integrated analysis of the transcriptome and metabolism of liver tissue in Triplophysa siluroides under heat stress (28 °C) and control (10 °C) conditions to identify heat stress-induced genes, metabolites and pathways. RNA-Seq identified 2373 differentially expressed genes, which consisted of 1360 upregulated genes and 1013 downregulated genes, in the heat stress group vs. the control group. Genes in the heat shock protein (Hsp) family, including Hsp40, Hsp70, Hsp90 and other Hsps, were strongly upregulated by heat stress. Pathway enrichment analysis revealed that the PI3K/AKT/mTOR and protein processing in the endoplasmic reticulum (ER) pathways were significantly affected by heat stress. Metabolism sequencing identified a total of 155 differentially abundant metabolites, including 118 significantly upregulated metabolites and 37 downregulated metabolites. Combined analysis of the transcriptome and metabolism results showed that ubiquitin-dependent proteolysis and purine metabolism pathways were enhanced in response to acute heat stress to protect cells from damage under stress conditions. The results of this study may contribute to our understanding of the underlying molecular mechanism of the heat stress response in cold-water fish.


Asunto(s)
Cipriniformes , Transcriptoma , Animales , Altitud , Fosfatidilinositol 3-Quinasas/genética , Perfilación de la Expresión Génica/veterinaria , Respuesta al Choque Térmico/genética , Cipriniformes/genética
10.
J Chromatogr A ; 1708: 464349, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37696129

RESUMEN

Enantioselective amino acid analysis is gaining increasing importance in pharmaceutical, biomedical and food sciences. While there are many methods available for enantiomer separation of amino acids, the simultaneous analysis of all chiral proteinogenic amino acids by a single method with one column and a single condition is still challenging. Herein, we report an enantioselective high-performance liquid chromatography-tandem mass spectrometry (LC-MS) assay using Chiralpak QN-AX as chiral column. With 6-aminoquinolyl-N-hydrosysuccinimidyl carbamate (AQC) as derivatization reagent, efficient enantioselective separation of D- and L-amino acids using HPLC has become possible. Thiol-containing amino acids like Cys are alkylated prior to AQC-labelling. A protocol for automated sample preparation including both derivatization step and calibrator preparation is presented. For compensating matrix effects, u-13C15N-labelled internal standards (IS) were employed. The method was validated and applied to the enantioselective analysis of amino acids in a bacterial fermentation broth.


Asunto(s)
Aminoácidos , Espectrometría de Masas en Tándem , Yodoacetamida , Estereoisomerismo , Cromatografía Liquida , Carbamatos
11.
iScience ; 26(8): 107413, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37559901

RESUMEN

To analyze the differences between different-sized Acipenser dabryanus, we randomly selected 600 3-month-old A. dabryanus juveniles. Four months later, the blood and white muscle of these fish were analyzed. The results showed no significant difference in the length-weight relationship (LWR) b value between the large and small A. dabryanus. The levels of serum growth hormone (gh) and insulin-like growth factor 1 (igf1) in the large A. dabryanus were significantly lower than those in the small, whereas the activity levels of Total superoxide dismutase (T-sod) and catalase (cat) were opposite to the results of gh and igf1. A total of 212 and 245 metabolites showed significant changes in the positive and negative polarity mode, respectively. Among 3,308 proteins identified, 69 proteins showed upregulated expression, and 185 proteins showed downregulated expression. These results indicated that the growth advantage of A. dabryanus was closely related to glycolysis, protein synthesis, and antioxidant function.

12.
Dis Model Mech ; 16(8)2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37577930

RESUMEN

Hedgehog (Hh) signaling is well known for its crucial role during development, but its specific role in individual cell lineages is less well characterized. Here, we disrupted Hh signaling specifically in melanocytes by using Cre-mediated cell-type-specific knockout of the Hh regulator suppressor of fused (Sufu). Interestingly, corresponding mice were fully pigmented and showed no developmental alterations in melanocyte numbers or distribution in skin and hair follicles. However, there were ectopic melanoblasts visible in the anterior chamber of the eye that eventually displayed severe malformation. Choroidal melanocytes remained unaltered. Surprisingly, the abnormal accumulation of anterior uveal melanoblasts was not the result of increased cell proliferation but of increased migration to ectopic locations such as the cornea. In melanoblasts in vitro, Sufu knockdown replicated the increase in cell migration without affecting proliferation and was mediated by an increased level of phosphorylated-ERK brought about by a reduction in the levels of the repressor form of GLI3. These results highlight the developmental divergence of distinct melanocyte subpopulations and may shed light on the pathogenesis of human ocular melanocytosis.


Asunto(s)
Proteínas Hedgehog , Melanocitos , Proteínas Represoras , Animales , Humanos , Ratones , Linaje de la Célula , Proteínas Represoras/genética , Piel
13.
Sci Bull (Beijing) ; 68(19): 2180-2189, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37558535

RESUMEN

Chemical transformation strategy is capable of fabricating nanomaterials with well-defined structures and fascinating performance via controllable crystallization kinetics in the phase transformation. V2CTx MXene has been used as precursors to fabricate vanadium porphyrin metal-organic frameworks (V-PMOFs) via the coordination of deprotonated carboxylic acid ligands. However, the rational and in-depth exploration of synthesis mechanism with the aim of enriching the variety of MXene (i.e., Ti3C2Tx) and organic ligands (i.e., catechol-based) to design new MOFs is rarely reported. Herein, we have first developed a metal ion assistant transformation strategy to synthesize three-dimensional catechol-based TiCu-HHTP (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) MOFs with a non-interpenetrating SrSi2 (srs) framework using two-dimensional Ti3C2Tx as precursors. The unique synergetic transformation mechanism involves the electron transfer from Ti3C2Tx to electrostatically adsorbed Cu2+ ion for redox reaction, the subsequent Ti-C bond rupture for Ti4+ ion release, and the continuous chelation coordination between Ti4+/Cu2+ and HHTP. Ti3C2Tx precursors and auxiliary metal ion could be rationally substituted by V2CTx and Mn+ (e.g., Ni2+, Co2+, Mn2+, and Zn2+), respectively. This strategy lays the foundation for the design and synthesis of innovative and multifarious MOFs derived from MXene or other unconventional metal precursors.

14.
J Int Med Res ; 51(6): 3000605231174973, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37282499

RESUMEN

Alveolar soft part sarcoma (ASPS) is an extremely rare type of soft tissue sarcoma. The primary sites of ASPS are mostly located in the extremities and trunk. Primary pulmonary ASPS is extremely rare. A search of the PubMed® database identified only five cases of primary pulmonary ASPS. This current case report describes the sixth case of ASPS in a 15-year-old male that presented with recurrent headaches. Head computed tomography showed space-occupying lesions in the left parietal lobe. Positron emission tomography-computed tomography confirmed the space-occupying lesions in the left parietal lobe and showed multiple nodules and masses in the two lungs and pleura, which were considered to be low-grade malignant mesenchymal tumours. The case report presents the clinical characteristics, diagnosis and treatment process. Programmed cell death protein 1 monoclonal antibody (sintilimab) combined with a tyrosine kinase inhibitor (anlotinib hydrochloride) achieved a good therapeutic effect, indicating that this combination therapy is worth exploring further. Large-scale prospective studies are needed to explore and develop standardized treatments for ASPS.


Asunto(s)
Sarcoma de Parte Blanda Alveolar , Neoplasias de los Tejidos Blandos , Masculino , Humanos , Adolescente , Sarcoma de Parte Blanda Alveolar/diagnóstico por imagen , Sarcoma de Parte Blanda Alveolar/tratamiento farmacológico , Sarcoma de Parte Blanda Alveolar/cirugía , Neoplasias de los Tejidos Blandos/patología , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Pulmón/patología
15.
Dalton Trans ; 52(22): 7620-7625, 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37195025

RESUMEN

A novel Ru(II) complex with a donor-acceptor-donor (D-A-D) ligand was designed and synthesized to prepare organic memory devices. The fabricated Ru(II) complex-based devices exhibited obvious bipolar resistance switching behavior with a low switching voltage (∼1.13 V) and a large ON/OFF ratio (105). The dominant switching mechanism can be explained by the distinct charge-transfer states endowed by the interaction between metals and ligands, which is verified by density functional theory (DFT) calculations. Excitingly, the device displays a much lower switching voltage than most of the previously reported metal complex based memory devices due to the intense intramolecular charge transfer caused by the strong built-in electric field in D-A systems. This work not only reveals the potential of the Ru(II) complex in resistive switching devices, but also provides new inspiration to manipulate the switching voltage at the molecular level.

16.
J Chromatogr A ; 1701: 464069, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37216850

RESUMEN

With the increasing numbers of nucleic acid-based pharmaceuticals like antisense oligonucleotides (ASO), small interfering ribonucleic acid (siRNA) entering the market, research facilities, pharmaceutical industries and also regulatory authorities have been looking for efficient analytical methods for these synthetic oligonucleotides (ON). Besides of conventional one-dimensional (1D) reversed-phase liquid chromatography with or without ion-pairing (IP-RP-LC, RP-LC), hydrophilic liquid chromatography (HILIC) and mixed-mode chromatography (MMC), two-dimensional (2D) approaches combining two orthogonal chromatographic techniques also become more relevant due to the high structural complexity of oligonucleotides. Recently, we tested a polybutylene terephthalate(PBT)-based stationary phase under ion-pairing free RP mode for the liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS) analysis of siRNA (Patisiran). In this study, retention profile and chromatographic orthogonality, respectively, were compared to other LC-modes like HILIC, IP-RPLC, another ion-pair free cholesterol-bonded RPLC and MMC considering their normalized retention times. Finally, because of higher orthogonality, the ion-pairing free PBT-bonded RPLC as first dimension (1D) was hyphenated with HILIC in the second dimension (2D) in a selective comprehensive 2D-LC setup leading to an enhanced resolution for peak purity evaluation of the main ON entities.


Asunto(s)
Cromatografía de Fase Inversa , Espectrometría de Masa por Ionización de Electrospray , Cromatografía de Fase Inversa/métodos , Cromatografía Liquida/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Oligonucleótidos/análisis , ARN Interferente Pequeño , Interacciones Hidrofóbicas e Hidrofílicas
17.
Inorg Chem ; 62(14): 5729-5736, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-36974386

RESUMEN

Scintillators can be widely applied to the fields of radioactivity detection, space exploration, and medical diagnosis and have attracted great attention. Recently, manganese(II) complexes with high-efficiency phosphorescent emission are expected to be good candidates for new scintillator materials. Herein, we design and synthesize a series of novel nonclassical binuclear neutral manganese(II) complexes with unique coordination modes, in which the crystal structures of CP1 and CP2 contain both four-coordinated and six-coordinated manganese(II) centers and CP3 is formed as a binuclear five-coordinated dichloro-bridged dimer. The single crystals of CP1-CP3 exhibit excellent stability, which can be attributed to their nonionic structures. They all exhibit intense red emission under UV and X-ray irradiation. Among the three manganese(II) complexes, CP1 demonstrates the best luminescence efficiency and X-ray scintillation performance with a high photoluminescence quantum yield (PLQY) of 91.9%, a relative light yield of 21037 photons MeV-1, and a detection limit of 34.45 nGyair s-1. Moreover, X-ray imaging based on CP1 scintillator screen demonstrates a spatial resolution of nearly 6 lp mm-1. As far as we know, this is the first report about stable binuclear neutral manganese(II) complexes for X-ray imaging and opens a new avenue for exploring novel scintillator materials.

18.
J Chromatogr A ; 1694: 463898, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36921562

RESUMEN

Nowadays, ion-pairing reversed-phase liquid chromatography (IP-RPLC) is the dominating generic method for the analysis of nucleic acid related compounds, such as antisense-oligonucleotides (ASO), small-interfering ribonucleic acid (siRNA) or other DNA or RNA type molecules and their conjugates. Despite of its effective performance, the usage of a high concentration of ion-pairing reagent in the eluent in IP-RPLC is unfavorable for the hyphenation with mass spectrometry (MS) which is required for a detailed structural characterization of the analytes and their structurally related impurities. In this work, we tested a polybutylene terephthalate (PBT)-bonded silica-based stationary phase for the separation of generically synthesized Patisiran as siRNA (antisense and sense single strands as well as their annealed double strand) giving some unexpected selectivity without any presence of ion-pairing reagents. Important chromatographic conditions affecting the separation have been investigated and evaluated. Furthermore, MS and tandem MS (MS/MS) characterization was possible without contamination of the MS system with ion-pair agent and related problems.


Asunto(s)
Cromatografía de Fase Inversa , Espectrometría de Masas en Tándem , Cromatografía de Fase Inversa/métodos , Oligonucleótidos/análisis , ARN Interferente Pequeño/química , Iones , Indicadores y Reactivos
19.
Food Chem ; 409: 135268, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-36592603

RESUMEN

This study explored the effect of three different industrial drying methods on the physicochemical, nutritional, and safety profile of goji berries. The hot-air (HD) and microwave drying (MD) methods yielded berries with relatively high polysaccharide content, while vacuum freeze-drying (FD) yielded dried berries with better sensory qualities but relatively less polysaccharide content. The polysaccharides obtained from the HD and MD berries had lower molecular weight, high antioxidant activity and high degrees of Maillard reaction. Further investigations revealed that all three methods, in particular HD and MD, generated high levels of intermediate Maillard reaction products (55.8-86.3 mg/kg) and advanced glycation end-products (fluorescent intensity of 26784-51712), based on significant reduction of reducing sugar and amino acids in the HD and MD berries (p < 0.05). These findings highlight the need to scrutinize the effectiveness of traditional and emerging drying technologies used to produce safe fruits.


Asunto(s)
Lycium , Lycium/química , Frutas/química , Desecación/métodos , Antioxidantes/química , Polisacáridos/química
20.
Ecotoxicol Environ Saf ; 249: 114366, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36508793

RESUMEN

Temperature fluctuations caused by climate change and global warming pose a great threat to various species. Most fish are particularly vulnerable to elevated temperatures. Understanding the mechanism of high-temperature tolerance in fish can be beneficial for proposing effective strategies to help fish cope with global warming. In this study, we systematically studied the effects of high temperature on Acipenser dabryanus, an ancient living fossil and flagship species of the Yangtze River, at the histological, biochemical, transcriptomic and metabolomic levels. Intestinal and liver tissues from the control groups (18 °C) and acute heat stress groups (30 °C) of A. dabryanus were sampled for histological observation and liver tissues were assessed for transcriptomic and metabolomic profiling. Histopathological analysis showed that the intestine and liver tissues were damaged after heat stress. The plasma cortisol content and the levels of oxidative stress markers (catalase/glutathione reductase) and two aminotransferases (aspartate aminotransferase/alanine aminotransferase) increased significantly in response to acute heat stress. Transcriptomic and metabolomic methods showed 6707 upregulated and 4189 downregulated genes and 64 upregulated and 78 downregulated metabolites in the heat stress group. Heat shock protein (HSP) genes showed striking changes in expression under heat stress, with 21 genes belonging to the HSP30, HSP40, HSP60, HSP70 and HSP90 families significantly upregulated by short-term heat stress. The majority of genes associated with ubiquitin and various immune-related pathways were also markedly upregulated in the heat stress group. In addition, the combined analysis of metabolites and gene profiles suggested an enhancement of amino acid metabolism and glycometabolism and the suppression of fatty acid metabolism during heat stress, which could be a potential energy conservation strategy for A. dabryanus. To the best of our knowledge, the present study represents the first attempt to reveal the mechanisms of heat stress responses in A. dabryanus, which can provide insights into improved cultivation of fish in response to global warming.


Asunto(s)
Peces , Transcriptoma , Animales , Peces/genética , Perfilación de la Expresión Génica , Respuesta al Choque Térmico/genética , Proteínas de Choque Térmico/genética
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