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1.
Opt Lett ; 49(7): 1774-1777, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38560860

RESUMO

An ultra-broadband TM-pass polarizer is designed, fabricated, and experimentally demonstrated based on subwavelength grating (SWG) metamaterials in a lithium niobate on an insulator (LNOI) platform. According to our simulation, the designed device is predicted to work at a 220 nm wavelength range from 1460 to 1680 nm, covering the S-, C-, L-, U-bands of optical fiber communication. By depositing and subsequently etching a silicon nitride thin film atop the LNOI chip, the SWG structures are formed successfully by using complementary metal-oxide semiconductor (CMOS)-compatible fabrication processes. The measured results show a high polarization extinction ratio larger than 20 dB and a relatively low insertion loss below 2.5 dB over a 130 nm wavelength range from 1500 to 1630 nm, mainly limited by the operation bandwidth of our laser source.

2.
Small ; : e2312281, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456782

RESUMO

The low-toxic and environmentally friendly 2D lead-free perovskite has made significant progress in the exploration of "green" X-ray detectors. However, the gap in detection performance between them and their lead-based analogues remains a matter of concern that cannot be ignored. To reduce this gap, shortening the interlayer spacing to accelerate the migration and collection of X-ray carriers is a promising strategy. Herein, a Dion-Jacobson (DJ) lead-free double perovskite (4-AP)2 AgBiBr8 (1, 4-AP = 4-amidinopyridine) with an ultra-narrow interlayer spacing of 3.0 Å, is constructed by utilizing π-conjugated aromatic spacers. Strikingly, the subsequent enhanced carrier transport and increased crystal density lead to X-ray detectors based on bulk single crystals of 1 with a high sensitivity of 1117.3 µC Gy-1  cm-2 , superior to the vast majority of similar double perovskites. In particular, the tight connection of the inorganic layers by the divalent cations enhances structural rigidity and stability, further endowing 1 detector with ultralow dark current drift (3.06 × 10-8  nA cm-1  s-1  V-1 , 80 V), excellent multiple cycles switching X-ray irradiation stability, as well as long-term environmental stability (maintains over 94% photoresponse after 90 days). This work brings lead-free double perovskites one step closer to realizing efficient practical green applications.

3.
Langmuir ; 40(14): 7463-7470, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38551336

RESUMO

The light-fueled microparticle oscillator, exemplifying sustained driving in a static light source, potentially holds applications in fundamental physics, cellular manipulation, fluid dynamics, and various other soft-matter systems. The challenges of photodamage due to laser focusing on particles and the control of the oscillation direction have always been two major issues for microparticle oscillators. Here, we present an optical-thermal method for achieving a 3D microparticle oscillator with a fixed direction by employing laser heating of the gold film surface. First, the microparticle oscillation without direction limitation is studied. The photothermal conversion originates from the laser heating of a gold film. The oscillation mechanism is the coordination of the forces exerted on the particles, including the thermal convective force, thermophoresis force, and gravity. Subsequently, the additional Marangoni convection force, generated by the temperature gradient on the surface of a microbubble, is utilized to control the oscillation direction of the microparticle. Finally, a dual-channel oscillation mode is achieved by utilizing two microbubbles. During the oscillation process, the microparticle is influenced by flow field forces and temperature gradient force, completely avoiding optical damage to the oscillating microparticle.

4.
Proc Natl Acad Sci U S A ; 121(14): e2321611121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38547058

RESUMO

Malignant glioma exhibits immune evasion characterized by highly expressing the immune checkpoint CD47. RNA 5-methylcytosine(m5C) modification plays a pivotal role in tumor pathogenesis. However, the mechanism underlying m5C-modified RNA metabolism remains unclear, as does the contribution of m5C-modified RNA to the glioma immune microenvironment. In this study, we demonstrate that the canonical 28SrRNA methyltransferase NSUN5 down-regulates ß-catenin by promoting the degradation of its mRNA, leading to enhanced phagocytosis of tumor-associated macrophages (TAMs). Specifically, the NSUN5-induced suppression of ß-catenin relies on its methyltransferase activity mediated by cysteine 359 (C359) and is not influenced by its localization in the nucleolus. Intriguingly, NSUN5 directly interacts with and deposits m5C on CTNNB1 caRNA (chromatin-associated RNA). NSUN5-induced recruitment of TET2 to chromatin is independent of its methyltransferase activity. The m5C modification on caRNA is subsequently oxidized into 5-hydroxymethylcytosine (5hmC) by TET2, which is dependent on its binding affinity for Fe2+ and α-KG. Furthermore, NSUN5 enhances the chromatin recruitment of RBFOX2 which acts as a 5hmC-specific reader to recognize and facilitate the degradation of 5hmC caRNA. Notably, hmeRIP-seq analysis reveals numerous mRNA substrates of NSUN5 that potentially undergo this mode of metabolism. In addition, NSUN5 is epigenetically suppressed by DNA methylation and is negatively correlated with IDH1-R132H mutation in glioma patients. Importantly, pharmacological blockage of DNA methylation or IDH1-R132H mutant and CD47/SIRPα signaling synergistically enhances TAM-based phagocytosis and glioma elimination in vivo. Our findings unveil a general mechanism by which NSUN5/TET2/RBFOX2 signaling regulates RNA metabolism and highlight NSUN5 targeting as a potential strategy for glioma immune therapy.


Assuntos
5-Metilcitosina , 5-Metilcitosina/análogos & derivados , Proteínas de Ligação a DNA , Dioxigenases , Glioma , Proteínas Musculares , Humanos , 5-Metilcitosina/metabolismo , beta Catenina/metabolismo , Cromatina , Antígeno CD47/genética , RNA , Evasão da Resposta Imune , Glioma/patologia , RNA Mensageiro/metabolismo , Metiltransferases/metabolismo , RNA Nuclear Pequeno , Microambiente Tumoral , Fatores de Processamento de RNA/genética , Proteínas Repressoras/metabolismo
5.
Aging (Albany NY) ; 16(2): 1767-1780, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38244583

RESUMO

Approximately 10% of gastric cancers are associated with Epstein-Barr virus (EBV). Tremella fuciformis polysaccharides (TFPs) are characterized by antioxidative and anti-inflammatory effects in different diseases. However, whether TFP improves EBV-associated gastric cancer (EBVaGC) has never been explored. The effects of TFP on EBV-infected GC cell viability were determined using a CCK-8 assay and flow cytometry. Western blotting and RT-qPCR were performed to explore the expression of ferroptosis-related proteins. The CCK-8 assay showed that TFP decreased EBV-infected GC cell viability in a dose- and time-dependent manner. Flow cytometry assays indicated that TFP significantly induced EBV-infected GC cell death. TFP also reduced the migratory capacity of EBV-infected GC cells. Furthermore, treatment with TFP significantly increased the mRNA levels of PTGS2 and Chac1 in EBV-infected GC cells. Western blot assays indicated that TFP suppressed the expression of NRF2, HO-1, GPX4 and xCT in EBV-infected GC cells. More importantly, overexpression of NRF2 could obviously rescue TFP-induced downregulation of GPX4 and xCT in EBV-infected GC cells. In summary, we showed novel data that TFP induced ferroptosis in EBV-infected GC cells by inhibiting NRF2/HO-1 signaling. The current findings may shed light on the potential clinical application of TFP in the treatment of EBVaGC.


Assuntos
Basidiomycota , Infecções por Vírus Epstein-Barr , Ferroptose , Neoplasias Gástricas , Humanos , Herpesvirus Humano 4/genética , Neoplasias Gástricas/genética , Infecções por Vírus Epstein-Barr/complicações , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Sincalida/metabolismo
6.
Plant Sci ; 340: 111963, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38103698

RESUMO

Cell deformation often occurs during sample preparation and imaging with scanning electron microscope (SEM), especially with delicate samples, which influences the accuracy of the results. Here we investigate the influence of several preparation methods on cell deformation, using water content and tissue hardness as indicators to classify "delicate" samples of plant species. The degree of deformation in samples resulting from five preparation methods was measured at the tissue and single-cell levels, revealing that a cryo- and methanol-fixation produced lower degrees of tissue dimension deformation and better preservation of cell shape for delicate samples, while for harder tissues, other preparation methods for a dehydrated specimen are also suitable. Stability and image quality of delicate samples could be improved with the application of a cryo-protectant combined with a lower cryo-stage temperature, e.g. - 30 °C. We show that the sample stability under the beam was improved by combining larger sample size and cryo-stage application. Furthermore, the influence of adaxial and abaxial tissue surfaces, the accelerating voltage, and sputter coating time on sample stability and image quality was evaluated. Our study is valuable for artifact reduction and easy application of SEM.


Assuntos
Plantas , Água , Microscopia Eletrônica de Varredura , Temperatura
7.
Adv Sci (Weinh) ; 11(6): e2307593, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38151904

RESUMO

Circularly polarized light (CPL) detection has wide applications in many fields, where the anisotropy factor (gIph ) is an important indicator to characterize the CPL detection performance. So far, many materials with high gIph have been reported, however, the exploration of the regulation of gIph is still in its infancy. Herein, two novel alternating chiral-achiral cations intercalation-type chiral hybrid perovskites (CHPs), named (R/S-1-phenylpropylamine)(propylamine)PbBr4 (1-R/S), exhibit above room-temperature (RT) polar-phase transition, which greatly regulates the gIph value. The gIph of 1-R is 0.04 in high-temperature phase chiral non-polar (P21 21 21 ) by applying 5 V bias, interestingly, with the temperature decrease, the gIph value in low-temperature phase chiral polar (P21 ) gradually increases (0.22@360K, 0.40@340K, 0.47@320K), and finally reaches a maximum of 0.5 at RT. Such value is not only the highest among 2D CHPs to date, but presents a 12.5-fold amplification compared with 0.04. Further, this rare phenomenon should be attributed to the built-in electric field induced by the polar photovoltaic effect, which sheds light on further obtaining CHPs with large gIph .

8.
Small ; : e2307454, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37948430

RESUMO

Lead halide hybrid perovskites have made great progress in direct X-ray detection and broadband photodetection, but the existence of toxic Pb and the demand for external operating voltage have severely limited their further applications and operational stability improvements. Therefore, exploring "green" lead-free hybrid perovskite that can both achieve X-ray detection and broadband photodetection without external voltage is of great importance, but remains severely challenging. Herein, using centrosymmetric (BZA)3 BiI6 (1, BZA = benzylamine) as a template, a pair of chiral-polar lead-free perovskites, (BZA)2 (R/S-PPA)BiI6 (2-R/S, R/S-PPA = (R/S)-1-Phenylpropylamine) are successfully obtained by introducing chiral aryl cations of (R/S)-1-Phenylpropylamine. Compared to 1, chiral-polar 2-R presents a significant irradiation-responsive bulk photovoltaic effect (BPVE) with an open circuit photovoltage of 0.4 V, which enables it with self-powered X-ray, UV-vis-NIR broadband photodetection. Specifically, 2-R device exhibits an ultralow detection limit of 18.5 nGy s-1 and excellent operational stability. Furthermore, 2-R as the first lead-free perovskite achieves significant broad-spectrum (377-940 nm) photodetection via light-induced pyroelectric effect. This work sheds light on the rational crystal reconstruction engineering and design of "green" hybrid perovskite toward high-demanded self-powered radiation detection and broadband photodetection.

9.
J Am Chem Soc ; 145(46): 25134-25142, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37956441

RESUMO

Chiral hybrid perovskites combine the advantages of chiral materials and halide perovskites, offering an ideal platform for the design of circularly polarized light (CPL) detectors. The pyro-phototronic effect, as a special mechanism of the photoexcited pyroelectric signal, can significantly improve the performance of photodetectors, whereas it remains a great challenge to achieve pyroelectricity-based CPL detection. In this work, the chiroptical phenomena and the pyro-phototronic effect are combined in chiral-polar perovskites to achieve unprecedented pyroelectric-based CPL detection. Two novel two-dimensional (2D) lead-free chiral-polar double perovskites, S/R-[(4-aminophenyl)ethylamine]2AgBiI8·0.5H2O, are successfully designed and synthesized by introducing chiral organic ligands into metal halide frameworks. Strikingly, the photoresponse is substantially boosted with the support of the pyro-phototronic effect, showing an increased pyro-phototronic current that is 40 times greater than the photovoltaic current. Furthermore, the pyroelectric-based detector possesses excellent CPL detection capacity to distinguish different polarization states of CPL photons, which achieve an impressive glph of up to 0.27 at zero bias. This study provides a brand new process for CPL detection by utilizing the pyro-phototronic effect in chiral-polar perovskites, which opens a new avenue for chiral materials in optoelectronic applications.

10.
Mater Horiz ; 10(11): 5307-5312, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37750819

RESUMO

The intrinsic integration of structural flexibility, chiroptical activity, and photoelectric properties endows the two-dimensional (2D) chiral hybrid perovskites (CHPs) with significant application potential in chiroptoelectronics and spintronics. However, the scarcity of suitable chiral organic ligands severely hinders their extensive construction, necessitating the development of new strategies for designing 2D CHPs. Herein, by exploiting a half substitution method, we created a pair of 2D CHPs with alternating cations in the interlayer space (ACI), (R/S-PPA)(PA)PbBr4 (2R/2S, PPA = 1-phenylpropylamine, PA = n-pentylamine), from the achiral Ruddlesden-Popper (RP) (PA)2PbBr4 (1). The successful chirality transfer induces 2R/2S to crystallize in the chiral P212121 space group and thus acquire appealing chiroptical activity. Consequently, the single-crystal devices of 2R exhibit good distinguishability to the left- and right-handed circularly polarized 405 nm lights with a photocurrent dissymmetric factor of 0.10 at 10 V bias. This work demonstrates an intriguing achiral RP to chiral ACI motif reconstruction in 2D halide hybrid perovskites, opening a door for expanding the family of 2D CHPs.

11.
Biomed Pharmacother ; 166: 115314, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37579695

RESUMO

Although all-trans retinoic acid (ATRA)-induced differentiation has transformed acute promyelocytic leukemia (APL) from the most fatal to the most curable hematological disease, resistance to ATRA in high-risk APL patients remains a clinical challenge. In this paper, we discovered that dihydroorotate dehydrogenase (DHODH) inhibition overcame ATRA resistance. 416, a potent DHODH inhibitor previously obtained in our group, inhibited the occurrence of APL in cells and model mice. Excitingly, 416 effectively overcame ATRA resistance in vitro and in vivo by inducing apoptosis and differentiation. Further mechanistic studies showed that PML/RARα lost the regulation of Bcl-2 and c-Myc in NB4-R1 cells, which probably contributed to ATRA resistance. Notably, 416 maintained its Bcl-2 and c-Myc down-regulation effect in NB4-R1 cells and overcome ATRA resistance by inhibiting DHODH. In conclusion, our study highlights the potential of 416 for APL therapy and overcoming ATRA resistance, supporting the further development of DHODH inhibitors for clinical use in refractory and relapsed APL.


Assuntos
Antineoplásicos , Di-Hidro-Orotato Desidrogenase , Resistencia a Medicamentos Antineoplásicos , Leucemia Promielocítica Aguda , Tretinoína , Animais , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Diferenciação Celular , Di-Hidro-Orotato Desidrogenase/antagonistas & inibidores , Di-Hidro-Orotato Desidrogenase/genética , Di-Hidro-Orotato Desidrogenase/metabolismo , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/metabolismo , Tretinoína/farmacologia , Tretinoína/uso terapêutico
12.
FASEB J ; 37(9): e23109, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37527216

RESUMO

LAMA5 (laminin α5) is a member of the laminin family. Despite the recent research implicating LAMA5 in cancer, the function of LAMA5 has remained uncertain in the progression of ovarian cancer (OC). Here, we investigated the functional influences of LAMA5 knockdown on OC in vitro and in vivo. In this study, we used immunohistochemistry (IHC) analysis to detect the relative expression of LAMA5 in OC and non-cancer tissues, and we analyzed its connection with the overall survival (OS) of OC patients. To prove the role of LAMA5 in cell proliferation, migration, and invasion, LAMA5 expression in OC cell lines was inhibited by lentivirus. Compared with normal fallopian tube tissue, epithelial ovarian cancer (EOC) tissue showed critically higher LAMA5 expression levels; additionally, high LAMA5 levels were a poor predictor of OS. We found that cell progression was restrained in LAMA5-knockdown OC cell lines in vivo and in vitro. Finally, LAMA5 might be a commanding inducer of the expression of epithelial-mesenchymal transition (EMT) and Notch signaling pathway-related markers. Together, our research indicates that LAMA5 is highly connected to OC progression as it may play a role in the EMT process through the Notch signaling pathway.


Assuntos
Neoplasias Ovarianas , Humanos , Feminino , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Transdução de Sinais , Proliferação de Células/genética , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica
13.
Proc Natl Acad Sci U S A ; 120(31): e2304755120, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37487067

RESUMO

Three-dimensional single-pixel imaging (3D SPI) has become an attractive imaging modality for both biomedical research and optical sensing. 3D-SPI techniques generally depend on time-of-flight or stereovision principle to extract depth information from backscattered light. However, existing implementations for these two optical schemes are limited to surface mapping of 3D objects at depth resolutions, at best, at the millimeter level. Here, we report 3D light-field illumination single-pixel microscopy (3D-LFI-SPM) that enables volumetric imaging of microscopic objects with a near-diffraction-limit 3D optical resolution. Aimed at 3D space reconstruction, 3D-LFI-SPM optically samples the 3D Fourier spectrum by combining 3D structured light-field illumination with single-element intensity detection. We build a 3D-LFI-SPM prototype that provides an imaging volume of ∼390 × 390 × 3,800 µm3 and achieves 2.7-µm lateral resolution and better than 37-µm axial resolution. Its capability of 3D visualization of label-free optical absorption contrast is demonstrated by imaging single algal cells in vivo. Our approach opens broad perspectives for 3D SPI with potential applications in various fields, such as biomedical functional imaging.

14.
J Ovarian Res ; 16(1): 126, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37386521

RESUMO

BACKGROUND: Ovarian cancer (OC) is one of the most common malignancies in women. It has a poor prognosis owing to its recurrence and metastasis. Unfortunately, reliable markers for early diagnosis and prognosis of OC are lacking. Our research aimed to investigate the value of the six-transmembrane epithelial antigen of prostate family member 3 (STEAP3) as a prognostic predictor and therapeutic target in OC using bioinformatics analysis. METHODS: STEAP3 expression and clinical data were acquired from The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), and Gene Expression Omnibus (GEO). Unsupervised clustering was used to identify molecular subtypes. Prognosis, tumor immune microenvironment (TIME), stemness indexes, and functional enrichment analysis were compared between two definite clusters. Through the least absolute shrinkage and selection operator (LASSO) regression analysis, a STEAP3-based risk model was developed, and the predictive effectiveness of this signature was confirmed using GEO datasets. A nomogram was used to predict the survival possibility of patients. Additionally, TIME, tumor immune dysfunction and exclusion (TIDE), stemness indexes, somatic mutations, and drug sensitivity were evaluated in different risk groups with OC. STEAP3 protein expression was detected using immunohistochemistry (IHC). RESULTS: STEAP3 displayed marked overexpression in OC. STEAP3 is an independent risk factor for OC. Based on the mRNA levels of STEAP3-related genes (SRGs), two distinct clusters were identified. Patients in the cluster 2 (C2) subgroup had a considerably worse prognosis, higher immune cell infiltration, and lower stemness scores. Pathways involved in tumorigenesis and immunity were highly enriched in the C2 subgroup. A prognostic model based on 13 SRGs was further developed. Kaplan-Meier analysis indicated that the overall survival (OS) of high-risk patients was poor. The risk score was significantly associated with TIME, TIDE, stemness indexes, tumor mutation burden (TMB), immunotherapy response, and drug sensitivity. Finally, IHC revealed that STEAP3 protein expression was noticeably elevated in OC, and overexpression of STEAP3 predicted poor OS and relapse-free survival (RFS) of patients. CONCLUSION: In summary, this study revealed that STEAP3 reliably predicts patient prognosis and provides novel ideas for OC immunotherapy.


Assuntos
Neoplasias Ovarianas , Próstata , Masculino , Humanos , Feminino , Recidiva Local de Neoplasia , Neoplasias Ovarianas/genética , Carcinogênese , Transformação Celular Neoplásica , Microambiente Tumoral/genética
15.
Adv Sci (Weinh) ; 10(21): e2301149, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37162209

RESUMO

Broadband photodetectors (PDs) with low detection limits hold significant importance to next-generation optoelectronic devices. However, simultaneously detecting broadband (i.e., X-ray to visible regimes) and weak lights in a single semiconducting material remains highly challenging. Here, by alloying iodine-substituted short-chain cations into the 3D FAPbI3 (FA = formamidine), a new 2D bilayered lead iodide hybrid perovskite, (2IPA)2 FAPb2 I7 (1, 2IPA = 2-iodopropylammonium), that enables addressing this challenge is reported. Such a 2D multilayered structure and lead iodide composition jointly endow 1 with a minimized dark current (6.04 pA), excellent electrical property, and narrow bandgap (2.03 eV), which further gives it great potential for detecting broadband weak lights. Consequently, its high-quality single crystal PDs exhibit remarkable photoresponses to weak ultraviolet-visible lights (377-637 nm) at several tens of nW cm-2 with high responsivities (>102  mA W-1 ) and significant detectivities (>1012 Jones). Moreover, 1 has an excellent X-ray detection performance with a high sensitivity of 438 µC Gy-1 cm-2 and an ultralow detection limit of 20 nGy s-1 . These exceptional attributes make 1 a promising material for broadband weak lights detection, which also sheds light on future explorations of high-performance PDs based on 2D hybrid perovskites.

17.
Neural Regen Res ; 18(4): 832-839, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36204851

RESUMO

The extracellular matrix surrounding oligodendrocytes plays an important role during myelination and remyelination in the brain. In many cases, the microenvironment surrounding demyelination lesions contains inhibitory molecules, which lead to repair failure. Accordingly, blocking the activity of these inhibitory factors in the extracellular matrix should lead to more successful remyelination. In the central nervous system, oligodendrocytes form the myelin sheath. We performed primary cell culture and found that a natural increase in fibronectin promoted the proliferation of oligodendrocyte progenitors during the initial stage of remyelination while inhibiting oligodendrocyte differentiation. Poly-L-ornithine blocked these inhibitory effects without compromising fibronectin's pro-proliferation function. Experiments showed that poly-L-ornithine activated the Erk1/2 signaling pathway that is necessary in the early stages of differentiation, as well as PI3K signaling pathways that are needed in the mid-late stages. When poly-L-ornithine was tested in a lysolecithin-induced animal model of focal demyelination, it enhanced myelin regeneration and promoted motor function recovery. These findings suggest that poly-L-ornithine has the potential to be a treatment option for clinical myelin sheath injury.

18.
J Chromatogr Sci ; 61(7): 656-664, 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36349369

RESUMO

Meropenem is a wide inter-individual variability in the pharmacokinetic, and standard dosing may not be adequate in critically ill patients. Therapeutic drug monitoring is a useful tool to optimize dosing. Meropenem is the amphoteric compound with an isoelectric point of 5.15. The secondary amino group of meropenem is positively charged when pH ≤ 5.4, thus we attempted to separate by strong cation exchange (SCX) column using acetonitrile/25-mM potassium dihydrogen phosphate (pH 3.0; 60:40) as mobile phase, and good peak shape and effective separation obtained. Generally, meropenem were unstable in plasma. We try to investigate stability of plasma samples using the medium QC sample with or without 3-(N-morpholino) propanesulfonic acid (MOPS) as stabilizer solutions at possible conditions during handling and storage. Meropenem showed higher stability at -80°C, and addition of MOPS might increase the short-term and extracted samples stability. This method is suitable for the quantification of meropenem in human plasma from 0.5 to 100 µg/mL. The accuracy was ranged from 96.53 to 101.11% with relative standard deviation ≤ 4.76%. The method has been used for determined 63 critically ill patients treated with meropenem. During the first measurement, 11 patients showed trough levels below the target ranges despite standard dosing. Through continuous or prolonged infusion, 8/11 patients (72.73%) led to adequate trough levels. The described SCX-high-performance liquid chromatography method for meropenem in human plasma is a powerful tool for therapeutic drug monitoring.


Assuntos
Antibacterianos , Monitoramento de Medicamentos , Humanos , Meropeném , Antibacterianos/análise , Cromatografia Líquida de Alta Pressão/métodos , Monitoramento de Medicamentos/métodos , Estado Terminal
19.
J Cell Mol Med ; 26(21): 5539-5550, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36251949

RESUMO

Larotrectinib (Lar) is a highly selective and potent small-molecule inhibitor used in patients with tropomyosin receptor kinase (TRK) fusion-positive cancers, including colon cancer. However, the underlying molecular mechanisms specifically in patients with colon cancer have not yet been explored. Our data showed that Lar significantly suppressed proliferation and migration of colon cancer cells. In addition, Lar suppressed the epithelial-mesenchymal transition (EMT) process, as evidenced by elevation in E-cadherin (E-cad), and downregulation of vimentin and matrix metalloproteinase (MMP) 2/9 expression. Furthermore, Lar was found to activate autophagic flux, in which Lar increased the ratio between LC3II/LC3I and decreased the expression of p62 in colon cancer cells. More importantly, Lar also increased AMPK phosphorylation and suppressed mTOR phosphorylation in colon cancer cells. However, when we silenced AMPK in colon cancer cells, Lar-induced accumulation of autolysomes as well as Lar-induced suppression of the EMT process were significantly diminished. An in vivo assay also confirmed that tumour volume and weight decreased in Lar-treated mice than in control mice. Taken together, this study suggests that Lar significantly suppresses colon cancer proliferation and migration by activating AMPK/mTOR-mediated autophagic cell death.


Assuntos
Morte Celular Autofágica , Neoplasias do Colo , Camundongos , Animais , Proteínas Quinases Ativadas por AMP/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Autofagia , Neoplasias do Colo/tratamento farmacológico , Transição Epitelial-Mesenquimal , Linhagem Celular Tumoral , Proliferação de Células/fisiologia
20.
Front Surg ; 9: 969154, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36061039

RESUMO

Introduction: Idiopathic mesenteric phlebosclerosis colitis (IMP) is a rare condition that impairs colonic venous blood return owing to mesenteric venous sclerosis and fibrosis. At present, many studies have suggested that long-term intake of Chinese herbal medicines is associated with its pathogenesis. IMP has no characteristic clinical manifestations, and most patients with IMP present with acute intestinal obstruction. As a rare disease, the etiology, pathogenesis, pathophysiology, and treatment of IMP are being explored and studied. Case Description: A 60-year-old Chinese male patient with IMP was admitted to our hospital for acute intestinal obstruction, received subtotal colectomy and ileostomy after 10 days of ineffective conservative treatment, and was discharged after postoperative supportive treatment for 1 month. Conclusion: There are many causes of intestinal obstruction, and we report a relatively rare one. After failure of conservative treatment, it is necessary to surgically resect part of the diseased bowel.

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