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1.
Dalton Trans ; 2024 May 23.
Article in English | MEDLINE | ID: mdl-38780236

ABSTRACT

Herein, a series of N-doped Ti3C2/porous g-C3N4 composites are ultrasonically prepared from N-doped Ti3C2 and porous g-C3N4 under N2 atmosphere. The structure, morphology, and optical characteristics of the as-prepared composites are characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, UV-vis diffuse reflectance spectroscopy, etc. Moreover, photocatalytic measurements show that N-doped Ti3C2 is an excellent modifier for porous g-C3N4 to heighten its photocatalytic activity. Only 44.1% of rhodamine B can be degraded by the photocatalysis of pristine porous g-C3N4, while the photocatalytic degradation ratio of rhodamine B can reach up to 97.5% for the optimal N-doped Ti3C2 loading composites under visible light for 15 min. Moreover, the photocatalytic tests of N2 fixation confirm that the optimal composites show the highest production yield of NH4+ (11.8 µmol gcat-1 h-1), which is 2.11-folds more than that of porous g-C3N4 (5.6 µmol gcat-1 h-1). The reinforced photocatalytic properties are revealed to profit from the more photogenerated electrons and holes' separation, higher ability for light response, and more abundant active sites. This work develops the route for boosting the photocatalytic properties of porous g-C3N4 with N-doped Ti3C2.

2.
Org Lett ; 2024 May 23.
Article in English | MEDLINE | ID: mdl-38780900

ABSTRACT

A novel three-component coupling reaction of ethynylbenziodoxolones (EBXs) with CO2 and amines has been achieved via silver catalysis, thereby providing an efficient method for the construction of a range of structurally diverse and valuable O-ß-oxoalkyl carbamates. The transformation proceeds under mild reaction conditions and exhibits a wide substrate scope and good functional group compatibility. In addition, this strategy could be extended to the synthesis of α-acyloxyketones using carboxylic acids as the nucleophiles to react with EBXs.

3.
Physiol Meas ; 45(5)2024 May 21.
Article in English | MEDLINE | ID: mdl-38697205

ABSTRACT

Objectives.The purpose of this study is to investigate the age dependence of bilateral frontal electroencephalogram (EEG) coupling characteristics, and find potential age-independent depth of anesthesia monitoring indicators for the elderlies.Approach.We recorded bilateral forehead EEG data from 41 patients (ranged in 19-82 years old), and separated into three age groups: 18-40 years (n= 12); 40-65 years (n= 14), >65 years (n= 15). All these patients underwent desflurane maintained general anesthesia (GA). We analyzed the age-related EEG spectra, phase amplitude coupling (PAC), coherence and phase lag index (PLI) of EEG data in the states of awake, GA, and recovery.Main results.The frontal alpha power shows age dependence in the state of GA maintained by desflurane. Modulation index in slow oscillation-alpha and delta-alpha bands showed age dependence and state dependence in varying degrees, the PAC pattern also became less pronounced with increasing age. In the awake state, the coherence in delta, theta and alpha frequency bands were all significantly higher in the >65 years age group than in the 18-40 years age group (p< 0.05 for three frequency bands). The coherence in alpha-band was significantly enhanced in all age groups in GA (p< 0.01) and then decreased in recovery state. Notably, the PLI in the alpha band was able to significantly distinguish the three states of awake, GA and recovery (p< 0.01) and the results of PLI in delta and theta frequency bands had similar changes to those of coherence.Significance.We found the EEG coupling and synchronization between bilateral forehead are age-dependent. The PAC, coherence and PLI portray this age-dependence. The PLI and coherence based on bilateral frontal EEG functional connectivity measures and PAC based on frontal single-channel are closely associated with anesthesia-induced unconsciousness.


Subject(s)
Desflurane , Electroencephalography , Humans , Desflurane/pharmacology , Adult , Middle Aged , Aged , Electroencephalography/drug effects , Young Adult , Male , Female , Aged, 80 and over , Adolescent , Aging/physiology , Aging/drug effects , Frontal Lobe/drug effects , Frontal Lobe/physiology , Isoflurane/analogs & derivatives , Isoflurane/pharmacology , Anesthetics, Inhalation/pharmacology , Anesthesia, General
4.
Front Microbiol ; 15: 1378029, 2024.
Article in English | MEDLINE | ID: mdl-38655089

ABSTRACT

Campylobacter jejuni (C. jejuni) is a common pathogen that often causes diarrhea, loss of appetite, and even enteritis in domestic cats, affecting their growth and development, especially in kittens under 6 months of age. Oral passive immunization with chicken yolk antibody Y has been proved effective for the treatment of gastrointestinal pathogen infections due to its high specificity. In this study, C. jejuni was isolated from diarrheal cat feces, and the specific egg yolk antibody Y against C. jejuni was demonstrated to effectively inhibit its proliferation in vitro experiments. To evaluate the effect of anti-C. jejuni IgY, the mouse C. jejuni infection model was established and it was found that IgY could alleviate C. jejuni-induced clinical symptoms. Consistent with these results, the reduction of pro-inflammatory factors and intestinal colonization by C. jejuni in the IgY-treated groups, especially in the high dose group. We then evaluated the protective effect of IgY on young Ragdoll cats infected with C. jejuni. This specific antibody reduced the rate of feline diarrhea, protected the growth of young cats, inhibited systemic inflammatory hyperactivation, and increased fecal short-chain fatty acid concentrations. Notably, IgY may have a protective role by changing intestinal amino acid metabolism and affecting C. jejuni chemotaxis. Collectively, specific IgY is a promising therapeutic strategy for C. jejuni-induced cat diarrhea.

5.
Org Lett ; 26(17): 3530-3535, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38656165

ABSTRACT

State-of-the-art strategies for alkene-hydroxyazidation, which yield a mixture of ß-azido alcohol and ß-azido peroxide, must rely on phosphine reagents to improve the chemoselectivity. To overcome the above problems, we present a photochemical hydroxyazidation of alkenes via Mn-mediated ligand-to-metal charge transfer (LMCT) in O2, which activates N3- to •N3 and incorporates O2 to be used as an oxygen source in the hydroxyazidation products. Broad alkene range and step-economy chemistry for the hydroxyazidation transformation were also demonstrated.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124331, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-38669983

ABSTRACT

Herein, a collection of novel N-Ti3C2/BiOClxBr1-x composites are fabricated via a simple in-situ sonochemical process. Not only the preparation method for N-Ti3C2 but also the photocatalytic system of N-Ti3C2/BiOClxBr1-x are firstly developed. Multiple characterizations jointly demonstrate the successful fabrication of the composites. Compared to that of BiOClxBr1-x, the maximum improvements of 1.16, 1.25 and 1.26 folds are severally confirmed for the photocatalytic degradation of levofloxacin, Rhodamine B, and methylene blue over N-Ti3C2/BiOClxBr1-x composites. In addition, through radicals trapping tests, the primary active species in photocatalytic degradation process are verified to be O2-. Moreover, N-Ti3C2/BiOClxBr1-x composites also exhibit 1.18 and 1.14 times enhancements for NH3 production compared with that of BiOClxBr1-x with or without the presence of methanol, respectively. In addition, the maximum improvements of photo-current and photo-potential for BiOClxBr1-x are 1.29 and 1.86 folds with the introduction of N-Ti3C2, respectively. The enhanced photocatalytic activity of N-Ti3C2/BiOClxBr1-x composites is owing to the heightened light absorption, increased specific surface area, and accelerated separation of photoinduced carriers. Additionally, the stable photocatalytic properties of N-Ti3C2/BiOClxBr1-x are confirmed by three photocatalytic recycle tests on pollutant degradation and nitrogen reduction combined with X-ray diffraction patterns before and after three recycles. This study suggests that N-Ti3C2 is an efficient ornamentation for boosting photocatalytic activity ofBiOClxBr1-x, which can also be expanded as a promising modifier for other semiconductors.

7.
Se Pu ; 42(4): 360-367, 2024 Apr.
Article in Chinese | MEDLINE | ID: mdl-38566425

ABSTRACT

The macroporous anion exchange chromatographic medium (FastSep-PAA) was prepared through grafting polyallylamine (PAA) onto polyacrylate macroporous microspheres (FastSep-epoxy). The effects of the synthesis conditions, including the PAA concentration, reaction time, and reaction solution pH, on the ion exchange (IC) of the medium were investigated in detail. When the PAA concentration, reaction time, and reaction solution pH were increased, the IC of the medium increased, and optimal synthesis conditions were then selected in combination with changes of protein binding capacity. A scanning electron microscope was used to examine the surface morphology of the medium. The medium possessed high pore connectivity. Furthermore, the pore structure of the medium was preserved after the grafting of PAA onto the macroporous microspheres. This finding demonstrates that the density of the PAA ligands does not appear to have any discernible impact on the structure of the medium; that is, no difference in the structure of the medium is observed before and after the grafting of PAA onto the microspheres. The pore size and pore-size distribution of the medium before and after grafting were determined by mercury intrusion porosimetry and the nitrogen adsorption method to investigate the relationship between pore size (measured in the range of 300-1000 nm) and protein adsorption. When the pore size of the medium was increased, its protein binding capacity did not exhibit any substantial decrease. An increase in pore size may hasten the mass transfer of proteins within the medium. Among the media prepared, that with a pore size of 400 nm exhibited the highest dynamic-binding capacity (DBC: 70.3 g/L at 126 cm/h). The large specific surface area of the medium and its increased number of protein adsorption sites appeared to positively influence its DBC. When the flow rate was increased, the protein DBC decreased in media with original pore sizes of less than 700 nm. In the case of the medium with an original pore size of 1000 nm, the protein DBC was independent of the flow rate. The protein DBC decreased by 3.5% when the flow rate was increased from 126 to 628 cm/h. In addition, the protein DBC was maintained at 57.7 g/L even when the flow velocity was 628 cm/h. This finding reveals that the diffusion rate of protein molecules at this pore size is less restricted and that the prepared medium has excellent mass-transfer performance. These results confirm that the macroporous polymer anion exchange chromatographic medium developed in this study has great potential for the high-throughput separation of proteins.


Subject(s)
Polyamines , Proteins , Chromatography, Ion Exchange/methods , Adsorption , Proteins/chemistry , Anions
8.
Article in English | MEDLINE | ID: mdl-38656108

ABSTRACT

Topological insulators (TIs) with spin-momentum-locked surface states and considerable spin-to-charge conversion (SCC) efficiency are ideal substitutes for the nonmagnetic layer in the traditional ferromagnetic/nonmagnetic (FM/NM) spintronic terahertz (THz) emitters. Here, the TI/ferrimagnetic structure as an effective polarization tunable THz source is verified by terahertz emission spectroscopy. The emitted THz electric field can be separated into two THz components utilizing their opposite symmetry on pump polarization and the magnetic field. TI not only emits a THz electric field via the linear photogalvanic effect (LPGE) but also serves as the medium of SCC via the inverse Edelstein effect (IEE) in the heterostructure. In addition, the amplitude and polarity of the SCC component can be efficiently manipulated by temperature in our ferrimagnetic TbFeCo layer compared with Co or Fe. Once these two THz components are delicately set orthogonally, an elliptical THz wave is generated by the intrinsic phase difference at the THz frequency range. The feasible control of its polarization and chirality is demonstrated by three means: pump polarization, magnetic field, and temperature. These appealing observations may pave the way for the development of elliptical THz wave emitters and polarization-sensitive THz spectroscopy.

9.
J Transl Med ; 22(1): 169, 2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38368407

ABSTRACT

BACKGROUND: Adenomatous polyps (APs) with inflammation are risk factors for colorectal cancer. However, the role of inflammation-related gut microbiota in promoting the progression of APs is unknown. METHODS: Sequencing of the 16S rRNA gene was conducted to identify characteristic bacteria in AP tissues and normal mucosa. Then, the roles of inflammation-related bacteria were clarified by Spearman correlation analysis. Furthermore, colorectal HT-29 cells, normal colon NCM460 cells, and azoxymethane-treated mice were used to investigate the effects of the characteristic bacteria on progression of APs. RESULTS: The expression levels of inflammation-related markers (diamine oxidase, D-lactate, C-reactive protein, tumor necrosis factor-α, interleukin-6 and interleukin-1ß) were increased, whereas the expression levels of anti-inflammatory factors (interleukin-4 and interleukin-10) were significantly decreased in AP patients as compared to healthy controls. Solobacterium moorei (S. moorei) was enriched in AP tissues and fecal samples, and significantly positively correlated with serum inflammation-related markers. In vitro, S. moorei preferentially attached to HT-29 cells and stimulated cell proliferation and production of pro-inflammatory factors. In vivo, the incidence of intestinal dysplasia was significantly increased in the S. moorei group. Gavage of mice with S. moorei upregulated production of pro-inflammatory factors, suppressed proliferation of CD4+ and CD8+cells, and disrupted the integrity of the intestinal barrier, thereby accelerating progression of APs. CONCLUSIONS: S. moorei accelerated the progression of AP in mice via activation of the NF-κB signaling pathway, chronic low-grade inflammation, and intestinal barrier disruption. Targeted reduction of S. moorei presents a potential strategy to prevent the progression of APs.


Subject(s)
Adenomatous Polyps , Firmicutes , Humans , Animals , Mice , RNA, Ribosomal, 16S/genetics , Inflammation/complications , Adenomatous Polyps/complications
10.
Hepatol Commun ; 8(3)2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38407327

ABSTRACT

Metabolic dysfunction-associated steatotic liver disease (MASLD), a replacement of the nomenclature employed for NAFLD, is the most prevalent chronic liver disease worldwide. Despite its high global prevalence, NAFLD is often under-recognized due to the absence of reliable noninvasive biomarkers for diagnosis and staging. Growing evidence suggests that the gut microbiome plays a significant role in the occurrence and progression of NAFLD by causing immune dysregulation and metabolic alterations due to gut dysbiosis. The rapid advancement of sequencing tools and metabolomics has enabled the identification of alterations in microbiome signatures and gut microbiota-derived metabolite profiles in numerous clinical studies related to NAFLD. Overall, these studies have shown a decrease in α-diversity and changes in gut microbiota abundance, characterized by increased levels of Escherichia and Prevotella, and decreased levels of Akkermansia muciniphila and Faecalibacterium in patients with NAFLD. Furthermore, bile acids, short-chain fatty acids, trimethylamine N-oxide, and tryptophan metabolites are believed to be closely associated with the onset and progression of NAFLD. In this review, we provide novel insights into the vital role of gut microbiome in the pathogenesis of NAFLD. Specifically, we summarize the major classes of gut microbiota and metabolic biomarkers in NAFLD, thereby highlighting the links between specific bacterial species and certain gut microbiota-derived metabolites in patients with NAFLD.


Subject(s)
Gastrointestinal Microbiome , Microbiota , Non-alcoholic Fatty Liver Disease , Humans , Non-alcoholic Fatty Liver Disease/diagnosis , Metabolomics , Bile Acids and Salts
11.
Theriogenology ; 218: 254-266, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38367334

ABSTRACT

Bloom (BLM) helicase plays an important role in DNA replication and the maintenance of genome integrity. BLM protein deficiency, which plays a vital role in the sperm-egg union and germ-cell development during reproduction, can lead to severe DNA damage in goats. However, the effect of BLM protein deficiency on goat litter size has not been reported. Herein, we studied the association between the genetic variation in the BLM gene and the number of kids per litter in Guizhou white goats. We explored differences in the expression of the BLM protein in the follicles of single and multi-kid nanny goats. We also analyzed the effects of dysregulated BLM gene expression on the proliferation and apoptosis of ovarian granulosa cells and the expression of genes related to follicle development in goats. Five single nucleotide polymorphism (SNP) loci, including the non-synonymous mutations g.38179 A > G, g.40626 G > C and g.89621 T > G; the intron synonymous mutation g.56961 G > A and the exon synonymous mutation g.65796 C > T were found in the BLM gene. All SNPs loci were in Hardy-Weinberg equilibrium, and correlation analysis showed that the g.65796 C > T and g.89621 T > G loci polymorphism was strongly associated with litter size in the first three litters (P < 0.05). The diplogenotype Hap 2/2 (AAGGAACCTT) showed no significant difference in litter size between different births, indicating that the diploid genotype is stable in different litter sizes. Bioinformatics analysis showed that three non-synonymous mutation loci (p.T488A, p.A662S, and p.S1373A) could affect BLM protein stability, and mutations in p.T488A and p.S1373A led to changes in amino acid polarity and associated interactions. qPCR results showed that the expression level of the BLM gene in the uterus and ovaries of TT genotype nanny goats was significantly higher than that of GG genotype nanny goats. Indirect immunofluorescence assay (IF) showed that the BLM protein was significantly overexpressed in both the primordial and growing follicles of nanny goats with multiple kids (P < 0.01). Disrupting BLM gene expression in the ovarian granulosa cells down-regulated the expression of the Cyp19A1 gene. It also significantly inhibited the proliferation of follicles and induces early apoptosis of the granulosa cells. These findings confirm that polymorphism in the BLM gene is closely related to the littering traits of Guizhou white goats, and it affects the reproductive performance of nanny goats by regulating the development of the oocytes and granulosa cells. This work provides new evidence on the regulatory effect of the BLM gene on the litter size of nanny goats.


Subject(s)
Goat Diseases , Protein Deficiency , Male , Pregnancy , Female , Animals , Ovary , Goats/genetics , Semen , Litter Size/genetics , Polymorphism, Single Nucleotide , Genotype , Protein Deficiency/veterinary
12.
ACS Nano ; 18(3): 2261-2278, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38207332

ABSTRACT

Sepsis, which is the most severe clinical manifestation of acute infection and has a mortality rate higher than that of cancer, represents a significant global public health burden. Persistent methicillin-resistant Staphylococcus aureus (MRSA) infection and further host immune paralysis are the leading causes of sepsis-associated death, but limited clinical interventions that target sepsis have failed to effectively restore immune homeostasis to enable complete eradication of MRSA. To restimulate anti-MRSA innate immunity, we developed CRV peptide-modified lipid nanoparticles (CRV/LNP-RNAs) for transient in situ programming of macrophages (MΦs). The CRV/LNP-RNAs enabled the delivery of MRSA-targeted chimeric antigen receptor (CAR) mRNA (SasA-CAR mRNA) and CASP11 (a key MRSA intracellular evasion target) siRNA to MΦs in situ, yielding CAR-MΦs with boosted bactericidal potency. Specifically, our results demonstrated that the engineered MΦs could efficiently phagocytose and digest MRSA intracellularly, preventing immune evasion by the "superbug" MRSA. Our findings highlight the potential of nanoparticle-enabled in vivo generation of CAR-MΦs as a therapeutic platform for multidrug-resistant (MDR) bacterial infections and should be confirmed in clinical trials.


Subject(s)
Liposomes , Methicillin-Resistant Staphylococcus aureus , Nanoparticles , Receptors, Chimeric Antigen , Sepsis , Staphylococcal Infections , Animals , Mice , Receptors, Chimeric Antigen/therapeutic use , Staphylococcal Infections/drug therapy , RNA, Messenger , Anti-Bacterial Agents/pharmacology , Macrophages , Sepsis/drug therapy , Lipids/pharmacology
13.
Huan Jing Ke Xue ; 45(1): 343-353, 2024 Jan 08.
Article in Chinese | MEDLINE | ID: mdl-38216484

ABSTRACT

Since the 1990s, a large area of sloping farmland in a purple soil hilly region of southwest China was converted into an orchard to prevent soil erosion, increase soil fertility, and elevate economic benefits for farmers. In order to explore the spatial distribution of soil carbon (C) and nitrogen (N) fractions on the slope of returning arable lands to citrus orchards in purple soil hilly areas, a soil sampling event was carried out in a citrus orchard at the Yanting Agro-ecological Experimental Station of Purple Soil, Chinese Academy of Sciences, to examine the differences in soil C and N fractions and their influencing factors. The results showed that the slope position had significant effects on the contents of soil total nitrogen (TN), nitrate nitrogen (NO3--N), and dissolved organic carbon (DOC) (P < 0.05), but the effects were not obvious regarding the total organic carbon (SOC) and ammonia nitrogen (NH4+-N) of the soil (P > 0.05). For topsoil (0-30 cm), the variation trend of soil NO3--N content along the slope was upper slope < middle slope < lower slope, whereas the TN and DOC contents along the slope exhibited the trend of upper slope > middle slope > lower slope. The contents of soil C and N in each slope position generally showed a downward trend with increasing soil depth (0-30 cm). The contents of soil TN, SOC, NO3--N, and DOC were significantly affected by soil depth (P < 0.05). The TN storage (0-30 cm) significantly decreased from the top to the bottom within the soil slope, with a value of 2.37, 1.89, and 1.62 t·hm-2 (reported as N) for the upper slope, middle slope, and lower slope, respectively. There was no significant difference in SOC reserves along the slope, with a range from 56.12 to 58.48 t·hm-2 (reported as C). Our results provide scientific basis for understanding the spatial distribution of soil nutrients of the restored farmland in purple soil hilly areas. Our research suggests that the spatial distribution of soil carbon and nitrogen storage should not be ignored when predicting the response of soil nutrients to land use change.

14.
J Biophotonics ; 17(1): e202300278, 2024 01.
Article in English | MEDLINE | ID: mdl-37717259

ABSTRACT

In multi-distance coherent diffraction imaging, the task of distance calculation for multi-diffraction images is cumbersome. The information features are hard-to-extract and the region of interest extraction algorithms are difficult to be adopted. A universal salient feature region selection algorithm by using the area with the highest density of corners is proposed to extract the most representative feature region. In addition, equally spaced recording modes and mismatched diffraction distances will result in system noise and destroy image quality. The polydirectional maximum gradient is offered as a sharpness criterion to weigh a quantitative feature for the final pattern. A fast, sensitive, and high-accuracy autofocusing and sample reconstruction can be achieved using only a small number of images while ensuring that morphological properties and quantification of the reconstructions are not compromised. The proposed method is promising for biological and medical dynamic observations for computational imaging systems.


Subject(s)
Algorithms , Diagnostic Imaging
15.
Dalton Trans ; 53(3): 917-931, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38105741

ABSTRACT

In this work, N-graphyne is in situ coupled with BiOCl0.5Br0.5via a facile one-step sonochemical method. To our knowledge, both the synthesis strategy for BiOCl0.5Br0.5 and the N-graphyne/BiOCl0.5Br0.5 photocatalytic system are new developments. A collection of characterization methods is adopted to detect the morphologies, structures, and electronic and optical properties. The results demonstrate that wrinkle-like N-graphyne nanosheets successfully enwind around or on flower-like BiOCl0.5Br0.5 microspheres, which are regularly assembled by BiOCl0.5Br0.5 nanosheets. Compared with pristine BiOCl0.5Br0.5, N-graphyne/BiOCl0.5Br0.5 composites exhibit superior adsorption capacity and visible-light-driven photocatalytic degradation of levofloxacin. In particular, the optimal N-graphyne amount for ameliorating the photocatalytic performance of BiOCl0.5Br0.5 is ascertained. In addition, the good stable performance for photocatalysis is confirmed by four cycling experiments. The dominant active species is confirmed to be O2˙- during photodegradation. The improved photocatalytic activity is attributed to the enhanced visible light response and the accelerated transfer/separation of photogenerated carriers by N-graphyne, which are verified using UV-vis absorption spectra, photocurrents, photopotentials, Nyquist plots, and Mott-Schottky curves. This study develops a new perspective for the synthesis and modification of BiOX solid solution, which can be used as an efficient photocatalyst.

16.
Pharmaceuticals (Basel) ; 16(12)2023 Nov 23.
Article in English | MEDLINE | ID: mdl-38139769

ABSTRACT

Polydopamine (PDA) as a melanin-like biomimetic material with excellent biocompatibility, full spectrum light absorption capacity and antioxidation property has been extensively applied in the biomedical field. Based on the high reactivity of dopamine (DA), exploiting new strategies to fabricate novel PDA-based nano-biomaterials with controllable size and improved performance is valuable and desirable. Herein, we reported a facile way to synthesize pyrrole-doped polydopamine-pyrrole nanoparticles (PDA-nPY NPs) with tunable size and enhanced near-infrared (NIR) absorption capacity through self-oxidative polymerization of DA with PY in an alkaline ethanol/H2O/NH4OH solution. The PDA-nPY NPs maintain excellent biocompatibility and surface reactivity as PDA. By regulating the volume of added PY, PDA-150PY NPs with a smaller size (<100 nm) and four-fold higher absorption intensity at 808 nm than that of PDA can be successfully fabricated. In vitro and in vivo experiments effectively further demonstrate that PDA-150PY NPs can effectively inhibit tumor growth and completely thermally ablate a tumor. It is believed that these PY doped PDA-nPY NPs can be a potential photothermal (PT) agent in biomedical application.

17.
Bioengineering (Basel) ; 10(12)2023 Nov 25.
Article in English | MEDLINE | ID: mdl-38135944

ABSTRACT

The emergence of modern prosthetics controlled by bio-signals has been facilitated by AI and microchip technology innovations. AI algorithms are trained using sEMG produced by muscles during contractions. The data acquisition procedure may result in discomfort and fatigue, particularly for amputees. Furthermore, prosthetic companies restrict sEMG signal exchange, limiting data-driven research and reproducibility. GANs present a viable solution to the aforementioned concerns. GANs can generate high-quality sEMG, which can be utilised for data augmentation, decrease the training time required by prosthetic users, enhance classification accuracy and ensure research reproducibility. This research proposes the utilisation of a one-dimensional deep convolutional GAN (1DDCGAN) to generate the sEMG of hand gestures. This approach involves the incorporation of dynamic time wrapping, fast Fourier transform and wavelets as discriminator inputs. Two datasets were utilised to validate the methodology, where five windows and increments were utilised to extract features to evaluate the synthesised sEMG quality. In addition to the traditional classification and augmentation metrics, two novel metrics-the Mantel test and the classifier two-sample test-were used for evaluation. The 1DDCGAN preserved the inter-feature correlations and generated high-quality signals, which resembled the original data. Additionally, the classification accuracy improved by an average of 1.21-5%.

18.
Adv Sci (Weinh) ; 10(36): e2303491, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37946702

ABSTRACT

Medical devices are commonly implanted underneath the skin, but how to real-time noninvasively monitor their migration, integrity, and biodegradation in human body is still a formidable challenge. Here, the study demonstrates that benzyl violet 4B (BV-4B), a main component in the FDA-approved surgical suture, is found to produce fluorescence signal in the first near-infrared window (NIR-I, 700-900 nm) in polar solutions, whereas BV-4B self-assembles into highly crystalline aggregates upon a formation of ultrasmall nanodots and can emit strong fluorescence in the second near-infrared window (NIR-II, 1000-1700 nm) with a dramatic bathochromic shift in the absorption spectrum of ≈200 nm. Intriguingly, BV-4B-involved suture knots underneath the skin can be facilely monitored during the whole degradation process in vivo, and the rupture of the customized BV-4B-coated silicone catheter is noninvasively diagnosed by NIR-II imaging. Furthermore, BV-4B suspended in embolization glue achieves hybrid fluorescence-guided surgery (hybrid FGS) for arteriovenous malformation. As a proof-of-concept study, the solid-state BV-4B is successfully used for NIR-II imaging of surgical sutures in operations of patients. Overall, as a clinically translatable solid-state dye, BV-4B can be applied for in vivo monitoring the fate of medical devices by NIR-II imaging.


Subject(s)
Coloring Agents , Optical Imaging , Humans , Optical Imaging/methods , Spectroscopy, Near-Infrared
19.
Risk Manag Healthc Policy ; 16: 2171-2185, 2023.
Article in English | MEDLINE | ID: mdl-37881168

ABSTRACT

Purpose: The willingness to utilize primary care services is crucial in explaining residents' healthcare-seeking behavior and decision-making in the context of the free choice of healthcare providers. This study examines China's family doctor contracting services system to elucidate the conceptual structure of the willingness to utilize primary care services and develop a reliable measurement tool. Methods: The study was conducted in two phases. Firstly, in-depth interviews were conducted with community residents, resulting in 42 qualitative data sets. Subsequently, a measurement scale for the willingness to utilize family doctor contracting services was developed, and the scale was validated through two surveys using exploratory factor analysis (N = 250) and confirmatory factor analysis (N = 278), respectively. Results: By employing a grounded theory approach, this study analyzes the connotation of willingness to utilize family doctor contracting services. It constructs a conceptual framework for the willingness to utilize primary care services. This conceptual framework consists of three dimensions: perceived feasibility, perceived desirability, and perceived initiative. Based on this framework, a measurement scale comprising 14 items was developed and subjected to rigorous validation procedures to ensure its reliability and validity. Conclusion: This study extends prior research on healthcare service utilization willingness by elucidating the internal willingness structure for primary healthcare services. It enhances our understanding of the connotation of healthcare service utilization willingness and develops a scientifically rigorous measurement tool. The findings of this study provide valuable insights into improving both the willingness and behavior of utilizing primary care services in healthcare systems where the hierarchical referral system still needs to be fully developed.

20.
Article in English | MEDLINE | ID: mdl-37883114

ABSTRACT

Spintronic terahertz (THz) emitters based on synthetic antiferromagnets (SAFs) of FM1/Ru/FM2 (FM: ferromagnet) have shown great potential for achieving coherent superposition and significant THz power enhancement due to antiparallel magnetization alignment. However, key issues regarding the effects of interlayer exchange coupling and net magnetization on THz emissions remain unclear, which will inevitably hinder the performance improvement and practical application of THz devices. In this work, we have investigated the femtosecond laser-induced THz emission in Pt (3)/CoFe (3)/Ru (tRu = 0-3.5)/CoFe (tCoFe = 1.5-10)/Pt (3) (in units of nm) films with compensated and uncompensated magnetic moments. Antiferromagnetic (AF) coupling occurs in the Ru thickness ranges of 0.2-1.1 and 1.9-2.3 nm, with the first peak (tRu = 0.4 nm) of the AF coupling field (Hex) significantly higher than that of the second peak (2.0 nm). Rather high THz amplitude is found for the samples with strong AF coupling. Nevertheless, despite the same remanence ratio of zero, the THz amplitude for the symmetric SAF films declines significantly as the tRu decreases from 0.8 to 0.4 nm, which is mainly ascribed to the noncolinear magnetization vectors due to the increased biquadratic coupling term. Specifically, we demonstrate that an asymmetric SAF structure with a dominant FM layer is more favored than the completely compensated one, which could generate significantly enhanced THz electric field with well-controlled polarity and intensity. In addition, as the temperature decreases, the THz emission intensity increases for the SAF samples of tRu = 0.9 nm with negligible biquadratic coupling, which is contrary to the decreasing trend of the tRu = 0.4 nm sample and has been attributed to the greatly enhanced Hex.

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