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1.
Small ; 20(1): e2304955, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37649168

RESUMEN

Novel functions and advanced structure, where each single component could not be produced individually, can exhibit from the collective and synergistic behavior of component systems. This synergetic strategy has been successfully demonstrated for co-assembly of polymer-polymer to construct hierarchical nanomaterials. However, differences in the natures of polymer and small molecules impose challenges in the construction of sophisticated co-assemblies with geometrical and compositional control. Herein, a synergetic self-assembly strategy is proposed to prepare organic-organic hybrid colloidal mesostructures by blending a liquid crystalline block copolymer (LC-BCP) with small molecular amphiphiles. Through a classic solvent-exchange process, amphiphiles embedded with LC-BCP realize multi-component nucleation and hierarchical assembly driven by anisotropic interaction from the LC ordering alignment of the core-forming block. 1D nanofibers with a periodic striped structure are formed by further LC component fusion and refinement. In addition, LC ordering effect of LC-BCP can be regulated by selecting appropriate solvents and leads to the formation of vesicular co-micelles. By means of the thermal-responsive behavior of amphiphiles, hexagonal pore arrays are finally generated on the surface of those vesicles.

2.
Angew Chem Int Ed Engl ; : e202417573, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39375155

RESUMEN

The widespread presence of hierarchical asymmetric structures in nature has sparked considerable interest because of their unique functionalities. These ingenious structures across multiple scales often emerge from the transfer and amplification of asymmetry from chiral molecules under various synergistic effects. However, constructing artificial chiral asymmetric structures, particularly in developing hierarchical multicomponent structures analogous to those formed in nature through synergistic non-covalent interactions, still presents tremendous challenges. Herein, we propose a co-assembly strategy to fabricate hierarchical chiral mesostructures by combining a liquid crystalline block copolymer (LC-BCP) with a small molecular amphiphile containing chiral alanine or phenylalanine as a linker. Through a classic solvent-exchange process, chiral amphiphiles embedded within LC-BCP finely regulate the LC ordering effect and facilitate transfer and amplification of asymmetry. Consequently, various co-assembled structures with significant hierarchical chirality features are obtained through synergetic effects. Remarkably, subtle alterations to the side groups of amino acids in the amphiphiles effectively adjust the hierarchical morphology transition. Moreover, the covalent bonding sequence of amino acids in the amphiphiles emerges as a critical factor governing the formation of hierarchical nanofibers and multilayered vesicles exhibiting a superhelical sense.

3.
Chem Biodivers ; 20(1): e202200574, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36382445

RESUMEN

Eleven polyphenols, classified as flavonoid glycosides, flavonoid aglycones, and phenolic acids, are important bioactive components in the capitula of Coreopsis tinctoria (CCT). Nevertheless, their full pharmacokinetic profiles have not been demonstrated simultaneously. Therefore, a liquid chromatography - tandem mass spectrometry (LC/MS/MS) method was developed in the present work and used it to study the pharmacokinetics of these 11 compounds. We performed LC/MS/MS with a gradient mobile phase composed of water containing 0.1 % formic acid and acetonitrile containing 0.1 % formic acid on a Proshell 120 SB C18 column (2.1 mm×100 mm, 2.7 µm). We achieved a good chromatographic peak shape, resolution, and mass signal response, and multiple reaction monitoring facilitated the simultaneous detection of 11 analytes. In addition, we validated the selectivity, correlation coefficient, precision, extraction recovery, matrix effects, and stability of the LC/MS/MS method to be acceptable for 11 analytes in rat plasma. Subsequently, rats were orally administered with 50 % ethanol eluent of CCT (ECCT). Nine of 11 polyphenols were absorbed quickly (except for QCD and TCA), and their plasma levels peaked within 40 min. The exposure and Cmax values of flavonoid glycosides and phenolic acids were lower than those of flavonoid aglycones. This is the first report to demonstrate the pharmacokinetics of 11 polyphenols in ECCT, which may play an important role in future studies of the bioactive components of ECCT and their bioactive mechanisms.


Asunto(s)
Coreopsis , Medicamentos Herbarios Chinos , Ratas , Animales , Espectrometría de Masas en Tándem/métodos , Polifenoles , Cromatografía Liquida/métodos , Flavonoides/química , Glicósidos/química , Medicamentos Herbarios Chinos/química , Administración Oral , Cromatografía Líquida de Alta Presión
4.
Int J Mol Sci ; 24(18)2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37762620

RESUMEN

Bacillus subtilis is a model organism for studying Gram-positive bacteria and serves as a cell factory in the industry for enzyme and chemical production. Additionally, it functions as a probiotic in the gastrointestinal tract, modulating the gut microbiota. Its lytic phage SPO1 is also the most studied phage among the genus Okubovrius, including Bacillus phage SPO1 and Camphawk. One of the notable features of SPO1 is the existence of a "host-takeover module", a cluster of 24 genes which occupies most of the terminal redundancy. Some of the gene products from the module have been characterized, revealing their ability to disrupt host metabolism by inhibiting DNA replication, RNA transcription, cell division, and glycolysis. However, many of the gene products which share limited similarity to known proteins remain under researched. In this study, we highlight the involvement of Gp49, a gene product from the module, in host RNA binding and heme metabolism-no observation has been reported in other phages. Gp49 folds into a structure that does not resemble any protein in the database and has a new putative RNA binding motif. The transcriptome study reveals that Gp49 primarily upregulates host heme synthesis which captures cytosolic iron to facilitate phage development.


Asunto(s)
Fagos de Bacillus , Bacteriófagos , Bacteriófagos/genética , Fagos de Bacillus/genética , Proteínas Virales/genética , División Celular , Proteínas de Unión al ARN/genética , Hemo , Bacillus subtilis/fisiología
5.
Molecules ; 28(22)2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-38005245

RESUMEN

A facile and efficient method has been developed for the synthesis of C3-difluoromethyl carbinol-containing imidazo[1,2-a]pyridines at room temperature via the HFIP-promoted Friedel-Crafts reaction of difluoroacetaldehyde ethyl hemiacetal and imidazo[1,2-a]pyridines. This strategy could be applied to the direct C(sp2)-H hydroxydifluoromethylation of imidazo[1,2-a]pyridines and afford a series of novel difluoromethylated carbinols in good to satisfactory yields with 29 examples. Furthermore, gram-scale and synthetic transformation experiments have also been achieved, demonstrating its potential applicable value in organic synthesis. This green protocol has several advantages, including being transition metal- and oxidant-free, being carried out at room temperature, having high efficiency, and having a wide substrate scope.

6.
Anal Bioanal Chem ; 414(19): 5917-5928, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35723722

RESUMEN

Flexible sensing is an alternative to traditional sensing and possesses good flexibility and wearability. Intrinsically conductive polymers, particularly poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS), have received significant attention due to their high mechanical flexibility and good biocompatibility. Here, we report the design of highly conductive and electrochemically active PEDOT:PSS-coated plastic substrate electrodes by combining N-doped graphene (NG) or S-doped graphene (SG) with methanesulfonic acid-treated PEDOT:PSS (denoted as NG-f-MSA-PEDOT:PSS/PET and SG-f-MSA-PEDOT:PSS/PET) by a simple drop-coating method. At room temperature, the NG-f-MSA-PEDOT:PSS/PET electrode demonstrated the lowest detection limits of 17.09, 33.84, 28.30, and 44.96 nM for paracetamol, uric acid, dopamine, and catechol (S/N = 3), respectively. The NG-f-MSA-PEDOT:PSS/PET electrode had good anti-interference ability and reproducibility without employing expensive noble metals and requiring much effort to polish the surface of traditional glass carbon electrodes. Most importantly, this film electrode could maintain a stable electrochemical response under different bending and crease states and had excellent mechanical stability and flexibility.


Asunto(s)
Dopamina , Grafito , Acetaminofén , Compuestos Bicíclicos Heterocíclicos con Puentes , Plásticos , Reproducibilidad de los Resultados , Ácido Úrico
7.
Chembiochem ; 22(6): 1042-1048, 2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33140570

RESUMEN

The development of small molecules that can selectively target G-quadruplex (G4) DNAs has drawn considerable attention due to their unique physiological and pathological functions. However, only a few molecules have been found to selectively bind a particular G4 DNA structure. We have developed a fluorescence ligand Q1, a molecular scaffold with a carbazole-pyridine core bridged by a phenylboronic acid side chain, that acts as a selective ascaris telomere antiparallel G4 DNA ASC20 ligand with about 18 nm blue-shifted and enhanced fluorescence intensity. Photophysical properties revealed that Q1 was sensitive to the microenvironment and gave the best selectivity to ASC20 with an equilibrium binding constant Ka =6.04×105  M-1 . Time-resolved fluorescence studies also demonstrated that Q1 showed a longer fluorescence lifetime in the presence of ASC20. The binding characteristics of Q1 with ASC20 were shown in detail in a fluorescent intercalator displacement (FID) assay, a 2-Ap titration experiment and by molecular docking. Ligand Q1 could adopt an appropriate pose at terminal G-quartets of ASC20 through multiple interactions including π-π stacking between aromatic rings; this led to strong fluorescence enhancement. In addition, a co-staining image showed that Q1 is mainly distributed in the cytoplasm. Accordingly, this work provides insights for the development of ligands that selectively targeting a specific G4 DNA structure.


Asunto(s)
Ascaris/genética , Colorantes Fluorescentes/química , G-Cuádruplex , Telómero/química , Animales , Sitios de Unión , Carbazoles/química , Dicroismo Circular , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Ligandos , Metales/química , Simulación del Acoplamiento Molecular , Conformación de Ácido Nucleico , Espectrometría de Fluorescencia
8.
Bioorg Med Chem Lett ; 53: 128438, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34740774

RESUMEN

Human serum albumin (HSA) in blood serves as an important biomarker for clinical diagnosis, and fluorescence sensing method has attracted extensive attention. In this work, a small organic molecule probe, YS8, involving twisted intramolecular charge transfer (TICT) characteristic, was designed and investigated to detect HSA. YS8 kept silent state in fluorescence under physiological conditions, but the encapsulation of YS8 in the hydrophobic subdomain IB region of HSA inhibited the TICT state and produced a clear light-up fluorescent signal. Especially, YS8 was demonstrated to be an efficient fluorogenic probe to discriminate HSA from other proteins including the bovine serum albumin (BSA). Moreover, YS8/HSA complex could be applied in fluorescence imaging in living cells and is also useful in the study of artificial fluorescent protein (AFP).


Asunto(s)
Diseño de Fármacos , Colorantes Fluorescentes/química , Imagen Óptica , Albúmina Sérica Humana/análisis , Animales , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Colorantes Fluorescentes/síntesis química , Ratones , Estructura Molecular , Relación Estructura-Actividad
9.
Arch Virol ; 166(3): 853-862, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33486629

RESUMEN

The aim of this study was to describe the distribution of human papillomavirus (HPV) genotypes among cervical cancers and pre-cancers in Shaanxi province of western China. A total of 17,341 women who were screened for cervical cancer from January 2014 to December 2016, using HPV genotyping and ThinPrep cytologic test were included. The prevalence and attribution of HPV genotypes were stratified by cervical lesion and age group. Of the subjects, 26.3% were infected with HPV, 28.0% of whom had multiple infections. The crude HPV prevalence increased from atypical squamous cells of undetermined significance/low-grade squamous intraepithelial lesions (ASCUS/LSIL, 64.3%) to high-grade squamous intraepithelial lesions (HSIL, 79.8%) and to invasive cervical cancer (ICC, 89.7%, P < 0.001). The three most prevalent genotypes were HPV 16 (8.0%), 58 (4.2%), and 52 (4.0%), and HPV 16, 31 and 33 were positively correlated with increased severity of cervical lesions. Additionally, the divalent vaccine genotypes HPV 16 and 18 accounted for 68.2% of ICC cases. Although 78.5% of ICC and 60.3% of HSIL cases were attributed to 9-valent vaccine genotypes, the other genotypes not covered by any vaccine still resulted in increases in coverage, with 1.5% for ICC, 5.3% for HSIL, and 13.5% for ASCUS/LSIL. HPV prevalence in western China was consistent with other regions of China. Early vaccination with 9-valent HPV vaccine is recommended in this locality for females younger than 26 years with no prior infection, while divalent the vaccine is more appropriate for women between 26 and 45 years, considering the efficacy, safety and cost-effectiveness of vaccines.


Asunto(s)
Papillomavirus Humano 16/aislamiento & purificación , Papillomavirus Humano 18/aislamiento & purificación , Papillomavirus Humano 31/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , Displasia del Cuello del Útero/epidemiología , Neoplasias del Cuello Uterino/epidemiología , Adulto , China/epidemiología , Femenino , Genotipo , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Papillomavirus Humano 31/genética , Humanos , Persona de Mediana Edad , Infecciones por Papillomavirus/prevención & control , Infecciones por Papillomavirus/virología , Vacunas contra Papillomavirus/uso terapéutico , Prevalencia , Neoplasias del Cuello Uterino/prevención & control , Neoplasias del Cuello Uterino/virología , Vacunación , Displasia del Cuello del Útero/virología
10.
Gut ; 69(9): 1598-1607, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-31857433

RESUMEN

OBJECTIVE: Gastrointestinal microbiota may be involved in Helicobacter pylori-associated gastric cancer development. The aim of this study was to explore the possible microbial mechanisms in gastric carcinogenesis and potential dysbiosis arising from H. pylori infection. DESIGN: Deep sequencing of the microbial 16S ribosomal RNA gene was used to investigate alterations in paired gastric biopsies and stool samples in 58 subjects with successful and 57 subjects with failed anti-H. pylori treatment, relative to 49 H. pylori negative subjects. RESULTS: In H. pylori positive subjects, richness and Shannon indexes increased significantly (both p<0.001) after successful eradication and showed no difference to those of negative subjects (p=0.493 for richness and p=0.420 for Shannon index). Differential taxa analysis identified 18 significantly altered gastric genera after eradication. The combination of these genera into a Microbial Dysbiosis Index revealed that the dysbiotic microbiota in H. pylori positive mucosa was associated with advanced gastric lesions (chronic atrophic gastritis and intestinal metaplasia/dysplasia) and could be reversed by eradication. Strong coexcluding interactions between Helicobacter and Fusobacterium, Neisseria, Prevotella, Veillonella, Rothia were found only in advanced gastric lesion patients, and were absent in normal/superficial gastritis group. Changes in faecal microbiota included increased Bifidobacterium after successful H. pylori eradication and more upregulated drug-resistant functional orthologs after failed treatment. CONCLUSION: H. pylori infection contributes significantly to gastric microbial dysbiosis that may be involved in carcinogenesis. Successful H. pylori eradication potentially restores gastric microbiota to a similar status as found in uninfected individuals, and shows beneficial effects on gut microbiota.


Asunto(s)
Disbiosis , Gastritis Atrófica , Microbioma Gastrointestinal/genética , Infecciones por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Antibacterianos/uso terapéutico , Biopsia/métodos , Disbiosis/diagnóstico , Disbiosis/microbiología , Heces/microbiología , Femenino , Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Gastritis Atrófica/microbiología , Gastritis Atrófica/patología , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/patología , Helicobacter pylori/aislamiento & purificación , Helicobacter pylori/patogenicidad , Humanos , Masculino , Metaplasia/microbiología , Metaplasia/patología , Interacciones Microbianas , Persona de Mediana Edad , ARN Ribosómico 16S/aislamiento & purificación , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología
11.
Can J Infect Dis Med Microbiol ; 2020: 8838447, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33312315

RESUMEN

BACKGROUND: With the wide use of antibiotics, antimicrobial resistance becomes a serious issue. Timely understanding of microbial pathogen profiles and the change of antimicrobial resistance provide an important guidance for effective and optimized use of antibiotics in local healthcare systems. The aim was to investigate the characteristics of microbial species and their antimicrobial resistances in a tertiary hospital with an Emergency Department and outpatient clinics for a period of six years. Methodology. A retrospective study was conducted using the HIS database of a tertiary hospital between 2013 and 2018. Antimicrobial susceptibility was tested by automated systems and/or the Kirby-Bauer disc diffusion method. The data were analyzed using the WHONET 5.6 software. The Cochran-Armitage test was used to study the trends over the period of research. RESULTS: In a total of 19,028 specimens submitted for microbial tests during the period from 49 units of the hospital, only the samples from the Emergency Department and Kidney Transplantation Clinic showed an annually significant increase (P < 0.001). More than 200 species with 46.4% gram-positive cocci and 45.3% gram-negative bacilli were identified in the 3,849 nonrepetitive isolates. The methicillin-resistant S. aureus and S. epidermidis rates were 25.1% and 74.6%, respectively. 60.9% E. coli and 33.5% K. pneumonia samples carried extended-spectrum-ß-lactamase. All Staphylococci and Enterococci samples were not resistant to linezolid, vancomycin, and tigecycline. In addition, only 0.01% E. coli, 1.1% K. pneumonia, and 18.7% P. aeruginosa isolates showed resistance to carbapenems. CONCLUSIONS: Vancomycin, linezolid and tigecycline were the most effective antibiotics for outpatients with gram-positive infection. Carbapenems were the most effective antibiotics for gram-negative infection. There was no significant annual increase of common multidrug resistances.

12.
Org Biomol Chem ; 17(20): 5138-5147, 2019 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-31073571

RESUMEN

A series of amino acid derivatives are successfully synthesized via a metal-free C-N coupling reaction of 5-alkoxy-3,4-dihalo-2(5H)-furanones and amino acids. Their structures are well characterized with 1H NMR, 13C NMR, ESI-MS and elemental analysis. As potential linkers of the 2(5H)-furanone unit with other drug moieties containing a hydroxyl or amino group, the effect of amino acids is investigated by comparison with other 2(5H)-furanone compounds by constructing C-O/C-S bonds. The preliminary results of the biological activity assay by the MTT method on a series of cancer cell lines in vitro reveal that the introduction of amino acids basically has no toxic effect. This can lead to these 2(5H)-furanone derivatives being further well-linked with other bioactive moieties with amino or hydroxy groups as expected. Thus, the biological activity assay gives a direction for the design of bioactive 2(5H)-furanones based on these amino acid linkers.


Asunto(s)
Alcoholes/farmacología , Aminoácidos/farmacología , Antineoplásicos/farmacología , Furanos/farmacología , Alcoholes/química , Aminoácidos/síntesis química , Aminoácidos/química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Furanos/química , Humanos , Estructura Molecular , Ratas , Relación Estructura-Actividad
13.
Cell Physiol Biochem ; 44(4): 1445-1459, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29190615

RESUMEN

Glycogen synthase kinase-3ß (GSK-3ß), a serine/threonine protein kinase, has been reported to show essential roles in molecular pathophysiology of many diseases. Mitochondrion is a dynamic organelle for producing cellular energy and determining cell fates. Stress-induced translocated GSK-3ß may interact with mitochondrial proteins, including PI3K-Akt, PGC-1α, HK II, PKCε, components of respiratory chain, and subunits of mPTP. Mitochondrial pool of GSK-3ß has been implicated in mediation of mitochondrial functions. GSK-3ß exhibits the regulatory effects on mitochondrial biogenesis, mitochondrial bioenergetics, mitochondrial permeability, mitochondrial motility, and mitochondrial apoptosis. The versatile functions of GSK-3ß might be associated with its wide range of substrates. Accumulative evidence demonstrates that GSK-3ß inactivation may be potentially developed as the promising strategy in management of many diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD). Intensive efforts have been made for exploring GSK-3ß inhibitors. Natural products provide us a great source for screening new lead compounds in inactivation of GSK-3ß. The key roles of GSK-3ß in mediation of mitochondrial functions are discussed in this review.


Asunto(s)
Glucógeno Sintasa Quinasa 3 beta/metabolismo , Mitocondrias/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Glucógeno Sintasa Quinasa 3 beta/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3 beta/química , Cloruro de Litio/farmacología , Cloruro de Litio/uso terapéutico , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Proteínas Mitocondriales/metabolismo
14.
Appl Opt ; 55(23): 6355-62, 2016 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-27534479

RESUMEN

A mid-infrared supercontinuum (SC) light source, which has important applications in many fields, has been extensively investigated in soft glass fibers. However, the poor instinct properties of soft glass fibers and the development of ultrashort pulse lasers left an opportunity for mid-infrared SC generation in silica fiber. Until now, silica fiber has been the commonly used medium for SC generation due to its outstanding properties. In this paper, mid-infrared SC generation in short silica photonic crystal fibers (PCFs) is investigated theoretically and systematically. In the case of a 1550�nm pump, the soliton self-frequency shift effect is utilized to extend the long wavelength edge of SC. Adopting a fiber that has a zero dispersion wavelength away from the pump pulse is a benefit for the suppression of blue spectral component and energy distribution in the long wavelength band. In the case of a 1950�nm pump, the generation of a red-shifted dispersive wave is an efficient way to extend the long wavelength edge of SC. Additionally, the coherence for femtosecond pulse pumping is discussed in this paper. Finally, the long wavelength edge of SC is beyond 3000�nm when a 1950�nm femtosecond pump pulse propagates in a PCF with negative dispersive slope around the pump pulse.

15.
Appl Opt ; 54(14): 4542-8, 2015 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-25967514

RESUMEN

Ultrabroadband supercontinuum has received considerable attention due to its numerous applications in practice. An ultrabroadband supercontinuum spanning from 426 to 2954 nm is generated numerically in this paper. It is achieved by dual-wavelength pumping with a specially designed silica photonic crystal fiber that has two widely separated zero dispersion wavelengths. Additionally, the wavelengths of dual-wavelength pumping are both located in the anomalous dispersion regime in our investigation, which differs from research ever reported. Detailed physical mechanisms as well as interaction between the injected two pulses are discussed explicitly. With the introduction of a second pump pulse in the infrared region, a blueshifted dispersive wave is excited, turning out to be advantageous to extend a supercontinuum further into ultraviolet. Interestingly, the infrared edges remain unchanged whether a pulse in near infrared is added or not. The pulse synchronization issue is studied thoroughly and the conclusion that the two pulses can encounter within the used fiber length is declared.

16.
Opt Express ; 22(20): 24179-91, 2014 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-25321993

RESUMEN

Mid-infrared supercontinuum generation (SCG) is mostly studied in fluoride glass fibers in which long fibers and high power pump sources are needed. Taking advantages of high nonlinearity and transparency, chalcogenide glass is also applied for SCG in mid-infrared region, where specific strategy is needed to compensate large normal material dispersion. We investigate multimaterial fibers (MMFs) combined with fluoride and chalcogenide glasses for SCG. The high refraction contrast allows the zero dispersion point of the fiber to shift to below 2 µm without air holes. These two materials have similar glass transition temperatures and thermal expansion coefficients. They are possible to be drawn together. Both step-index MMFs and microstructured MMFs (MS-MMFs) are considered. The chromatic dispersions and supercontinuum spectra are studied. A 20 dB bandwidth of over one octave SCG with high coherence can be obtained from a 1 cm MS-MMF at 1.95 µm with a pumping peak power of 175 W. As the pump power increased, the spectrum can extend to 5 µm. In this scheme the fiber is so short that the high level of loss, which is the feature of MMFs, will not cause problems.

17.
Small Methods ; : e2301525, 2024 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-38185748

RESUMEN

Functional hierarchy is prevalent in biological systems owing to natural evolution. Efforts to replicate these structures in artificial materials have gained traction in materials science. Although artificial hierarchical structures are fabricated at different scales based on site-specific interactions using ABC-type block copolymers (BCPs), the fabrication of such hierarchical structures using AB-type BCPs via a simple and efficient method remains challenging. Herein, a class of amphiphilic BCPs (PDenm -b-PACholn ) is reported comprising dendronized oligoethylene glycol (Den) and cholesterol (AChol) as hydrophilic and hydrophobic moieties, respectively. By employing the collapse of PDenm blocks at a specific temperature, the fabrication of bundled fibers and multilayer vesicles is achieved with an obvious hierarchy. Different from common reversible aggregation-disaggregation processes of thermal-responsive polymers, the ordering of the core-forming block with liquid crystalline (LC) properties provides robustly physical cross-linking, coupled with epitaxial growth and the lateral fusion of LC blocks, guiding the formation of stable hierarchical micellar structures. It is highlighted that the combination of temperature-sensitive properties and LC ordering alignment offers a novel approach for constructing hierarchical structures using AB-type BCPs via an efficient one-step assembly method.

18.
Artículo en Inglés | MEDLINE | ID: mdl-39354758

RESUMEN

AIM: Psoriasis is an immune-mediated skin disease that occurs worldwide and is characterized by high prevalence and chronicity. Psoriasis has a complex pathogenesis and is difficult to cure. Therefore, continuous exploration of the pathogenesis of psoriasis and the search for new drug treatment methods are crucial for improving treatment efficiency and reducing psychological damage to psoriasis patients. The active ingredients in Dihuang Zicao granules (DHZCG) can effectively treat psoriasis. Therefore, this study aimed to analyze the active ingredients of DHZCG and their potential mechanisms for treating psoriasis. METHODS: The effective components of DHZCG were screened via the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). Genetic information for psoriasis was retrieved from the GeneCards, OMIM and DisGENET databases. Protein-Protein Interaction (PPI) analysis was performed, and component‒target‒disease networks were constructed. Important molecular biological processes and signaling pathways were screened via GO and KEGG analyses. Molecular docking of the active ingredients and key targets was performed via AutoDock Vina (1.1.2). A mouse model of psoriasis was established and divided into a control group, model group, low-dose DHZCG group (L-DHZCG), medium-dose DHZCG group (M-DHZCG), and high-dose DHZCG group (H-DHZCG). Hematoxylin and Eosin (HE) staining was performed to determine the pathological changes in the skin of each group of mice, and the Psoriasis Area Severity Index (PASI) score was used to assess skin damage. ELISA and RT‒ PCR were used to measure the levels of the inflammatory factors TNF-a, IL-17A, and IL-23 in the serum and skin tissue of the mice, respectively. Western blotting was used to analyze the expression of proteins related to the AGE/RAGE signaling pathway. Immunofluorescence was used to examine the expression of the inflammatory factor NF-kB. Immunohistochemistry was used to measure IL-1ß and TNF-a expression in skin tissues. RESULTS: Sixty genes associated with psoriasis treatment by DHZCG, including core genes encoding IL-6, TNF-a, AKT1, IL-1ß, TP53, NFKB1, BCL2, and MAPK3, were identified. Through the construction of a psoriasis mouse model, DHZCG treatment effectively reduced skin damage and significantly decreased the levels of the validated factors TNF-a, IL-17A, IL- 23, IL-1b, and NF-kB in the serum and damaged skin. Furthermore, the reduction in the levels of these inflammatory factors by DHZCG is associated with the downregulation of the AGE/RAGE signaling pathway. CONCLUSION: DHZCG reduces inflammation and alleviates psoriasis by downregulating the AGE/RAGE/NF-kB signaling pathway. This study is beneficial for providing a theoretical basis for the development of drugs for psoriasis and for offering personalized treatment strategies for the clinical management of psoriasis.

19.
J Otol ; 19(1): 19-23, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38313760

RESUMEN

Background: Sudden sensorineural hearing loss (SSNHL) is a prevalent emergency in ear, nose, and throat practice. Previous studies have demonstrated that intratympanic steroid therapy (IST) can serve as a salvage treatment for SSNHL after the failure of systemic steroid therapy (SST). Objective: This study aimed to analyze the efficacy of modified IST involving the insertion of a tympanic tube and gelfoam as a salvage treatment for patients with SSNHL, and to explore its associated factors. Methods: Totally, 74 patients who were aged 22-81 years with SSNHL were enrolled and allocated to either the control group (n = 25) or the treatment group (n = 49) based on their treatment modalities. All patients received SST lasting for at least 7 days. Subsequently, patients in the treatment group, after SST failure, underwent IST twice a week for 2-6 weeks, while the control group did not. Efficacy was assessed by the improvement in pure tone average at the affected frequency at the beginning and end of IST. Results: Hearing improvement in all patients after IST in the treatment group was 9.71 ± 14.84 dB, with significant improvement at affected frequencies (250-8000 Hz) compared with the control group (P < 0.05). The findings indicated the duration from the onset of SSNHL to the beginning of IST as an independent factor for pure tone average improvement after treatment (P = 0.002), whereas age, duration of SST, and time of IST were not (P > 0.05). Conclusion: The modified IST was demonstrated to be a safe and effective method as a salvage treatment for SSNHL. This study explored the efficacy of a modified IST approach, incorporating the utilization of tympanic tubes and gelfoam as key components. The findings underscore the advantages of gelfoam as a strategic drug carrier placed in the round window niche. By minimizing drug loss, extending action time, and increasing perilymph concentration, gelfoam enhances the therapeutic impact of IST, contributing to improved hearing outcomes in patients with SSNHL.

20.
Otolaryngol Head Neck Surg ; 171(4): 1165-1171, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38822760

RESUMEN

OBJECTIVE: Recognition of auditory brainstem response (ABR) waveforms may be challenging, particularly for older individuals or those with hearing loss. This study aimed to investigate deep learning frameworks to improve the automatic recognition of ABR waveforms in participants with varying ages and hearing levels. STUDY DESIGN: The research used a descriptive study design to collect and analyze pure tone audiometry and ABR data from 100 participants. SETTING: The research was conducted at a tertiary academic medical center, specifically at the Clinical Audiology Center of Tsinghua Chang Gung Hospital (Beijing, China). METHODS: Data from 100 participants were collected and categorized into four groups based on age and hearing level. Features from both time-domain and frequency-domain ABR signals were extracted and combined with demographic factors, such as age, sex, pure-tone thresholds, stimulus intensity, and original signal sequences to generate feature vectors. An enhanced Wide&Deep model was utilized, incorporating the Light-multi-layer perceptron (MLP) model to train the recognition of ABR waveforms. The recognition accuracy (ACC) of each model was calculated for the overall data set and each group. RESULTS: The ACC rates of the Light-MLP model were 97.8%, 97.2%, 93.8%, and 92.0% for Groups 1 to 4, respectively, with a weighted average ACC rate of 95.4%. For the Wide&Deep model, the ACC rates were 93.4%, 90.8%, 92.0%, and 88.3% for Groups 1 to 4, respectively, with a weighted average ACC rate of 91.0%. CONCLUSION: Both the Light-MLP model and the Wide&Deep model demonstrated excellent ACC in automatic recognition of ABR waveforms across participants with diverse ages and hearing levels. While the Wide&Deep model's performance was slightly poorer than that of the Light-MLP model, particularly due to the limited sample size, it is anticipated that with an expanded data set, the performance of Wide&Deep model may be further improved.


Asunto(s)
Audiometría de Tonos Puros , Aprendizaje Profundo , Potenciales Evocados Auditivos del Tronco Encefálico , Humanos , Masculino , Femenino , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Persona de Mediana Edad , Adulto , Anciano , Adulto Joven , Pérdida Auditiva/diagnóstico , Pérdida Auditiva/fisiopatología , Adolescente
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