Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 872
Filtrar
1.
J Mater Chem B ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775048

RESUMEN

Nanoparticles have been regarded as a promising vaccine adjuvant due to their innate immune potentiation and enhanced antigen transport. However, the inefficient infiltration into the lymph node (LN) paracortex of nanoparticles caused by subcapsular sinus (SCS) obstruction is the main challenge in further improvement of nanovaccine immune efficacy. Herein, we propose to overcome paracortex penetration by using nanovaccine to spontaneously and continuously release antigens after retention in the SCS. In detail, we utilized a spontaneous retro-Diels-Alder (r-D-A) reaction linker to connect poly{(2-methyl-2-oxazoline)80-co-[(2-butyl-2-oxazoline)15-r-(2-thioethyl-2-oxazoline)8]} (PMBOxSH) and peptides for the peptide nanovaccine construction. The r-D-A reaction linker can spontaneously break over time, allowing the nanovaccine to release free antigens and adjuvants upon reaching the LN, thereby facilitating the entry of released antigens and adjuvants into the interior of the LNs. We showed that the efficacy of the peptide nanovaccine constructed using this dynamic linker could be significantly improved, thus greatly enhancing the tumor inhibition efficacy in the B16-OVA model. This dynamic-covalent-chemistry-based vaccine strategy may inspire designing more efficient therapeutic vaccines, especially those that require eliciting high-amount T cell responses.

3.
Med Biol Eng Comput ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709337

RESUMEN

A finite element model of cervical kyphosis was established to analyze the stress of cervical spine under suspensory traction and to explore the mechanism and effect of it. A patient with typical cervical kyphosis (C2-C5) underwent CT scan imaging, and 3D slicer was used to reconstruct the C2 to T2 vertebral bodies. The reconstructed data was imported into Hypermesh 2020 and Abaqus 2017 for meshing and finite element analysis. The changes of the kyphotic angle and the von Mises stress on the annulus fibrosus of each intervertebral disc and ligaments were analyzed under suspensory traction conditions. With the increase of suspensory traction weight, the overall kyphosis of cervical spine showed a decreasing trend. The correction of kyphosis was mainly contributed by the change of kyphotic segments. The kyphotic angle of C2-C5 was corrected from 45° to 13° finally. In cervical intervertebral discs, the stress was concentrated to anterior and posterior part, except for C4-5. The stress of the anterior longitudinal ligament (ALL) decreased from the rostral to the caudal, and the high level von Mises stress of the kyphotic segments appeared at C2-C3, C3-C4, and C4-C5. The roles of the other ligaments were not obvious. The kyphotic angle was significantly reduced by the suspensory traction. Shear effect due to the high von Mises stress in the anterior and posterior parts of annulus fibrosus and the tension on the anterior longitudinal ligament play a role in the correction of cervical kyphosis.

4.
Heliyon ; 10(9): e30935, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38774082

RESUMEN

Crop protection pesticide spraying aims to greatly improve the utilization rate of pesticides. Controlling pesticides deposition requires a thorough understanding of the spatial behaviour of spray droplets.The Qinghai-Tibet Plateau, which is the headwaters of three largest water resources (Yangtze, Yellow and Lancang) in China, has exceptionally unique climatic characteristics. The goal is to reduce the amount of pesticides entering water resources. The wind tunnel experiment was used to validate the discrete phase method for tracking the trajectories. Cooperation between the smaller and larger droplets (greater than 150 µm) in the dense area around the nozzle can undoubtedly enhance the initial dispersion of droplet sizes. Droplet coalescence, which lowers the proportion of readily dispersed droplets, can greatly boost droplet deposition onto the target location.The crucial drift height is presented and clarified when droplets gradually disperse by identifying the descending length at which efficiency of mass transit starts towards decrease off quickly. The pesticide transport efficiency will not be enhanced by reducing the initial relative spread of droplets if the actual spray height surpasses the crucial drift height, and may even worsen drift loss. The temperature and relative humidity of the air have a greater influence on the evaporation losses of droplets smaller than 150 µm. In addition to providing information about pesticide spraying, the results of studies on droplet drift behaviors also suggest a method for controlling drift.

5.
Phytochemistry ; 224: 114150, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38763312

RESUMEN

In our search for neuroprotective agents, six previously undescribed highly oxidized guaiane sesquiterpenes, linderaggrols A-F (1-6), together with three known sesquiterpenes, were isolated from the roots of Lindera aggregata (Sims) Kosterm. Their structures including absolute configurations were established by a combination of NMR spectroscopic techniques and single crystal X-ray diffraction experiments. Compounds 1-6 represented the first instances of guaiane 12(8),15(6)-dilactones. Additionally, compound 6 possessed a rare 1,8-O-bridge. Neuroprotective effects against erastin-induced ferroptosis on HT-22 cells showed that some compounds demonstrated neuroprotective effects at 20.0 µM.

6.
Protein Cell ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38779805

RESUMEN

Microbial communities such as those residing in the human gut are highly diverse and complex, and many with important implications in health and diseases. The effects and functions of these microbial communities are determined not only by their species compositions and diversities but also by the dynamic intra- and inter-cellular states at the transcriptional level. Powerful and scalable technologies capable of acquiring single-microbe-resolution RNA sequencing information in order to achieve comprehensive understanding of complex microbial communities together with their hosts is therefore utterly needed. Here we report the development and utilization of a droplet-based smRNA-seq (single-microbe RNA sequencing) method capable of identifying large species varieties in human samples, which we name smRandom-seq2. Together with a triple-module computational pipeline designed for the bacteria and bacteriophage sequencing data by smRandom-seq2 in four human gut samples, we established a single-cell level bacterial transcriptional landscape of human gut microbiome, which included 29,742 single microbes and 329 unique species. Distinct adaptive responses states among species in Prevotella and Roseburia genus and intrinsic adaptive strategy heterogeneity in Phascolarctobacterium succinatutens were uncovered. Additionally, we identified hundreds of novel host-phage transcriptional activity associations in the human gut microbiome. Our results indicated the smRandom-seq2 is a high-throughput and high-resolution smRNA-seq technique that is highly adaptable to complex microbial communities in real-word situations and promises new perspectives in the understanding of human microbiomes.

8.
Artículo en Inglés | MEDLINE | ID: mdl-38702150

RESUMEN

Objective: To investigate the effect of meticulous management on infection prevention and infection rate control in neonatal wards. Methods: 230 neonates admitted to Northwest Women and Children's Hospital from January 2022 to June 2022 were selected as the control group and 230 neonates admitted to Northwest Women and Children's Hospital in the same period were selected as the study group. The control group was given routine management, and the study group was given meticulous management. The sanitary conditions of the items in the wards, the rate of implementation of standard disinfection measures, neonatal infections, and the satisfaction of neonatal guardians were compared between the two groups. Results: The qualified rates of air, nipple, bottle, disinfectants, sterilized items, and hand hygiene of medical staff in the study group were higher than those in the control group (P < .05). The implementation rates of environmental management, equipment disinfection, personnel management, and skin management disinfection in the neonatal ward of the study group were higher than those of the control group (P < .05). The total infection rate of all newborns in the study group was lower than that of the control group (P < .05). Total satisfaction was higher in the study group than in the control group (P < .05). Conclusion: Meticulous management can play an effective role in the prevention and control of hospital-acquired infections in neonatal wards, and can effectively reduce the infection rate, which can be promoted and applied in clinical settings.

9.
J Pharm Pharmacol ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38767973

RESUMEN

OBJECTIVES: GL-V9 exhibited anti-tumour effects on various types of tumours. This study aimed to verify if GL-V9 synergized with oxaliplatin in suppressing colorectal cancer (CRC) and to explore the synergistic mechanism. METHODS: The synergy effect was tested by MTT assays and the mechanism was examined by comet assay, western blotting and immunohistochemistry (IHC). Xenograft model was constructed to substantiated the synergy effect and its mechanism in vivo. RESULTS: GL-V9 was verified to enhance the DNA damage effect of oxaliplatin, so as to synergistically suppress colon cancer cells in vitro and in vivo. In HCT-116 cells, GL-V9 accelerated the degradation of Wee1 and induced the abrogation of cell cycle arrest and mis-entry into mitosis, bypassing the DNA damage response caused by oxaliplatin. Our findings suggested that GL-V9 binding to HSP90 was responsible for the degradation of Wee1 and the vulnerability of colon cancer cells to oxaliplatin. Functionally, overexpression of either HSP90 or WEE1 annulled the synergistic effect of GL-V9 and oxaliplatin. CONCLUSIONS: Collectively, our findings revealed that GL-V9 synergized with oxaliplatin to suppress CRC and displayed a promising strategy to improve the efficacy of oxaliplatin.

10.
Food Res Int ; 187: 114316, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38763629

RESUMEN

This study investigates the dynamic changes in the aroma profile of Tuo tea during long-term storage, a process not well understood yet critical to the formation of aged tea's unique characteristics. Aroma profiling of Tuo tea samples stored for 2 to 25 years was conducted using sensory evaluation and the HS-SPME/GC × GC-QTOFMS technique, revealing a progressive transition from fresh, fruity, and floral scents to more stale, woody, and herbal notes. Among 275 identified volatiles, 55 were correlated with storage duration (|r| > 0.8, p < 0.05), and 49 differential compounds (VIP > 1, FC > 1.2, FC < 0.833, p < 0.05) were identified across three storage stages (2-4, 5-10, and 13-25 years). Furthermore, theaspirane, eucalyptol, o-xylene, and 1-ethylidene-1H-indene were selected as potential markers of Tuo tea aging, incorporating the implementation of a Random Forest (RF) model. Additionally, our model exhibited high accuracy in predicting the age of Tuo tea within a prediction error range of -2.51 to 2.84 years. This research contributes to a comprehensive understanding of the impact of storage time on tea aroma and aids in the precise identification of tea age.


Asunto(s)
Almacenamiento de Alimentos , Cromatografía de Gases y Espectrometría de Masas , Odorantes , , Compuestos Orgánicos Volátiles , Odorantes/análisis , Té/química , Compuestos Orgánicos Volátiles/análisis , Almacenamiento de Alimentos/métodos , Factores de Tiempo , Humanos , Camellia sinensis/química , Microextracción en Fase Sólida
11.
Comput Biol Med ; 176: 108594, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38761501

RESUMEN

Skin cancer is one of the common types of cancer. It spreads quickly and is not easy to detect in the early stages, posing a major threat to human health. In recent years, deep learning methods have attracted widespread attention for skin cancer detection in dermoscopic images. However, training a practical classifier becomes highly challenging due to inter-class similarity and intra-class variation in skin lesion images. To address these problems, we propose a multi-scale fusion structure that combines shallow and deep features for more accurate classification. Simultaneously, we implement three approaches to the problem of class imbalance: class weighting, label smoothing, and resampling. In addition, the HAM10000_RE dataset strips out hair features to demonstrate the role of hair features in the classification process. We demonstrate that the region of interest is the most critical classification feature for the HAM10000_SE dataset, which segments lesion regions. We evaluated the effectiveness of our model using the HAM10000 and ISIC2019 dataset. The results showed that this method performed well in dermoscopic classification tasks, with ACC and AUC of 94.0% and 99.3%, on the HAM10000 dataset and ACC of 89.8% for the ISIC2019 dataset. The overall performance of our model is excellent in comparison to state-of-the-art models.

12.
Int J Biol Macromol ; 267(Pt 1): 131512, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38608972

RESUMEN

Two-dimensional (2D) transition metal carbides (Ti3C2Tx MXene) have gained significant attention for their potential in constructing diverse functional materials, However, MXene is easily oxidized and weakly bound to the cellulose matrix, which pose challenges in developing MXene-decorated non-woven fabric with strong bonding and stable thermal management properties. Herein, we successfully prepared deep eutectic supramolecular polymer (DESP) functionalized MXene to address these issues. MXene can be wrapped with DESP to be insulated from water and protected from being oxidized. Subsequently, we achieved an efficient in-situ deposition of DESP-functionalized MXene onto fibers through a combination of dip coating and photopolymerization technique. The resulting nonwoven fabric (CNs-DESP@M) exhibited excellent photothermal conversion properties along with rapid thermal response and functional stability. Interestingly, the interface bonding between MXene and the fiber surface was significantly enhanced due to the abundant pyrogallol groups in DESP, resulting in the composite textile exhibiting commendable mechanical properties (2.68 MPa). Moreover, the as-prepared textile demonstrates outstanding bactericidal efficacy against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The multifunctional textile, created through a facile and efficient approach, demonstrates remarkable potential for applications in smart textiles, catering to the diverse needs of individuals in the future.


Asunto(s)
Antibacterianos , Celulosa , Escherichia coli , Polímeros , Staphylococcus aureus , Textiles , Celulosa/química , Celulosa/farmacología , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Polímeros/química , Fenómenos Mecánicos , Temperatura , Viabilidad Microbiana/efectos de los fármacos
13.
J Am Chem Soc ; 146(17): 12225-12232, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38635866

RESUMEN

The control of spin relaxation mechanisms is of great importance for spintronics applications as well as for fundamental studies. Layered metal-halide perovskites represent an emerging class of semiconductors with rich optical spin physics, showing potential for spintronic applications. However, a major hurdle arises in layered metal-halide perovskites with strong spin-orbit coupling, where the spin lifetime becomes extremely short due to D'yakonov-Perel' scattering and Bir-Aronov-Pikus at high carrier density. Using the circularly polarized pump-probe transient reflection technique, we experimentally reveal the important scattering for spin relaxation beyond the electron-hole exchange strength in the Dion-Jacobson (DJ)-type 2D perovskites (3AMP)(MA)n-1PbnI3n+1 [3AMP = 3-(aminomethyl)piperidinium, n = 1-4]. Despite a more than 10-fold increase in carrier concentration, the spin lifetimes for n = 3 and 4 are effectively maintained. We reveal neutral impurity and polar optical phonon scatterings as significant contributors to the momentum relaxation rate. Furthermore, we show that more octahedral distortions induce a larger deformation potential which is reflected on the acoustic phonon properties. Coherent acoustic phonon analysis indicates that the polaronic effect is crucial in achieving control over the scattering mechanism and ensuring spin lifetime protection, highlighting the potential of DJ-phase perovskites for spintronic applications.

15.
Food Chem X ; 22: 101303, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38590631

RESUMEN

'Baimmaocha' is a distinctive resource for production of high-quality black tea, and its processed black tea has unique aroma characteristics. 190 volatile compounds were identified by comprehensive two-dimensional gas chromatography-olfactometry-quadrupole-time-of-flight mass spectrometry(GC × GC-O-Q-TOMS), and among them 23 compounds were recognized as key odorants contributing to forming different aroma characteristics in 'Baimaocha' black teas of Rucheng, Renhua, and Lingyun (RCBT, RHBT, LYBT). The odor activity value coupled with GC-O showed that methyl salicylate (RCBT), geraniol (RHBT), trans-ß-ionone and benzeneacetaldehyde (LYBT) might be the most definitive aroma compounds identified from their respective regions. Furthermore, PLS analysis revealed three odorants as significant contributors to floral characteristic, four odorants related to fruity attribute, four odorants linked to fresh attribute, and three odorants associated with roasted attribute. These results provide novel insights into sensory evaluation and chemical substances of 'Baimaocha' black tea and provide a theoretical basis for controlling and enhancement tea aroma quality.

17.
Gut Microbes ; 16(1): 2334970, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38563680

RESUMEN

Gastrointestinal (GI) infection is evidenced with involvement in COVID-19 pathogenesis caused by SARS-CoV-2. However, the correlation between GI microbiota and the distinct pathogenicity of SARS-CoV-2 Proto and its emerging variants remains unclear. In this study, we aimed to determine if GI microbiota impacted COVID-19 pathogenesis and if the effect varied between SARS-CoV-2 Proto and its variants. We performed an integrative analysis of histopathology, microbiomics, and transcriptomics on the GI tract fragments from rhesus monkeys infected with SARS-CoV-2 proto or its variants. Based on the degree of pathological damage and microbiota profile in the GI tract, five of SARS-CoV-2 strains were classified into two distinct clusters, namely, the clusters of Alpha, Beta and Delta (ABD), and Proto and Omicron (PO). Notably, the abundance of potentially pathogenic microorganisms increased in ABD but not in the PO-infected rhesus monkeys. Specifically, the high abundance of UCG-002, UCG-005, and Treponema in ABD virus-infected animals positively correlated with interleukin, integrins, and antiviral genes. Overall, this study revealed that infection-induced alteration of GI microbiota and metabolites could increase the systemic burdens of inflammation or pathological injury in infected animals, especially in those infected with ABD viruses. Distinct GI microbiota and metabolite profiles may be responsible for the differential pathological phenotypes of PO and ABD virus-infected animals. These findings improve our understanding the roles of the GI microbiota in SARS-CoV-2 infection and provide important information for the precise prevention, control, and treatment of COVID-19.


Asunto(s)
COVID-19 , Microbioma Gastrointestinal , Animales , SARS-CoV-2 , Virulencia , Macaca mulatta
18.
World J Clin Cases ; 12(11): 1974-1979, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38660558

RESUMEN

BACKGROUND: This case of gestational gingival tumor is huge and extremely rare in clinical practice. As the growth location of this gingival tumor is in the upper anterior tooth area, it seriously affects the pregnant woman's speech and food, causing great pain to the patient. The use of Nd:YGA water mist laser to remove the gingival tumor resulted in minimal intraoperative bleeding, minimal adverse reactions, and good postoperative healing, which is worthy of clinical promotion and application. CASE SUMMARY: The patient, a pregnant woman, reported a large lump in her mouth on the first day of postpartum treatment. Based on medical history and clinical examination, the diagnosis was diagnosed as gestational gingival tumor. Postoperative pathological biopsy also confirmed this diagnosis. The use of Nd:YAG water mist laser to remove the tumor resulted in minimal intraoperative bleeding, clear surgical field of view, short surgical time, and good postoperative healing. CONCLUSION: In comparison to traditional surgery, Nd:YAG water mist laser surgery is minimally invasive, minimizes cell damage, reduces bleeding, ensures a clear field of vision, and virtually eliminates postoperative edema, carbonization, and the risk of cross infection. It has unique advantages in oral soft tissue surgery for pregnant patients. Therefore, the clinical application of Nd:YAG water mist laser for the treatment of gestational gingival tumors is an ideal choice.

19.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(4): 371-377, 2024 Apr 15.
Artículo en Chino | MEDLINE | ID: mdl-38660901

RESUMEN

OBJECTIVES: To investigate the levels of serum folate and vitamin B12 (VB12) and their association with the level of neurodevelopment in preschool children with autism spectrum disorder (ASD). METHODS: A total of 324 ASD children aged 2-6 years and 318 healthy children aged 2-6 years were recruited. Serum levels of folate and VB12 were measured using chemiluminescent immunoassay. The Social Responsiveness Scale and the Childhood Autism Rating Scale were used to assess the core symptoms of ASD children, and the Gesell Developmental Schedule was employed to evaluate the level of neurodevelopment. RESULTS: The levels of serum folate and VB12 in ASD children were significantly lower than those in healthy children (P<0.05). Serum folate levels in ASD children were positively correlated with gross and fine motor developmental quotients (P<0.05), and serum VB12 levels were positively correlated with adaptive behavior, fine motor, and language developmental quotients (P<0.05). In ASD children aged 2 to <4 years, serum folate levels were positively correlated with developmental quotients in all domains (P<0.05), and serum VB12 levels were positively correlated with language developmental quotient (P<0.05). In male ASD children, serum VB12 levels were positively correlated with language and personal-social developmental quotients (P<0.05). CONCLUSIONS: Serum folate and VB12 levels in preschool ASD children are lower than those in healthy children and are associated with neurodevelopmental levels, especially in ASD children under 4 years of age. Therefore, maintaining normal serum folate and VB12 levels may be beneficial for the neurodevelopment of ASD children, especially in ASD children under 4 years of age.


Asunto(s)
Trastorno del Espectro Autista , Ácido Fólico , Vitamina B 12 , Humanos , Trastorno del Espectro Autista/sangre , Trastorno del Espectro Autista/etiología , Preescolar , Masculino , Femenino , Ácido Fólico/sangre , Vitamina B 12/sangre , Niño , Desarrollo Infantil
20.
Nanoscale ; 16(17): 8345-8351, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38606457

RESUMEN

2D WSe2-based electronic devices have received much research interest. However, it is still a challenge to achieve high electronic performance in WSe2-based devices. In this work, we report greatly enhanced performances of different thickness WSe2 ambipolar transistors and demonstrate homogeneous WSe2 inverter devices, which are obtained by using a semiconductor processing-compatible layer removal technique via chemical removal of the surface top WOx layer formed by O2 plasma treatment. Importantly, monolayer WSe2 was realised after several consecutive removal processes, demonstrating that the single layer removal is accurate and reliable. After subsequent removal of the top layer WOx by KOH, the fabricated WSe2 field-effect transistors exhibit greatly enhanced electronic performance along with the high electron and hole mobilities of 40 and 85 cm2 V-1 s-1, respectively. Our work demonstrates that the layer removal technique is an efficient route to fabricate high performance 2D material-based electronic devices.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA