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1.
Neural Regen Res ; 20(3): 845-857, 2025 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38886957

RESUMO

JOURNAL/nrgr/04.03/01300535-202503000-00029/figure1/v/2024-06-17T092413Z/r/image-tiff It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late stroke. Indeed, previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain tissue. Our previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke, but its specific role and mechanism are currently unclear. To simulate stroke in vivo, a middle cerebral artery occlusion rat model was established, with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic stroke. We found that in the early stage (within 24 hours) of ischemic stroke, neutrophils produced a large amount of hypochlorous acid, while in the recovery phase (10 days after stroke), microglia were activated and produced a small amount of hypochlorous acid. Further, in acute stroke in rats, hypochlorous acid production was prevented using a hypochlorous acid scavenger, taurine, or myeloperoxidase inhibitor, 4-aminobenzoic acid hydrazide. Our results showed that high levels of hypochlorous acid (200 µM) induced neuronal apoptosis after oxygen/glucose deprivation/reoxygenation. However, in the recovery phase of the middle cerebral artery occlusion model, a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and astrocytes. This suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion injury. Lower levels of hypochlorous acid (5 and 100 µM) promoted nuclear translocation of ß-catenin. By transfection of single-site mutation plasmids, we found that hypochlorous acid induced chlorination of the ß-catenin tyrosine 30 residue, which promoted nuclear translocation. Altogether, our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

2.
Front Neurosci ; 18: 1412559, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38966757

RESUMO

In neural circuits, recurrent connectivity plays a crucial role in network function and stability. However, existing recurrent spiking neural networks (RSNNs) are often constructed by random connections without optimization. While RSNNs can produce rich dynamics that are critical for memory formation and learning, systemic architectural optimization of RSNNs is still an open challenge. We aim to enable systematic design of large RSNNs via a new scalable RSNN architecture and automated architectural optimization. We compose RSNNs based on a layer architecture called Sparsely-Connected Recurrent Motif Layer (SC-ML) that consists of multiple small recurrent motifs wired together by sparse lateral connections. The small size of the motifs and sparse inter-motif connectivity leads to an RSNN architecture scalable to large network sizes. We further propose a method called Hybrid Risk-Mitigating Architectural Search (HRMAS) to systematically optimize the topology of the proposed recurrent motifs and SC-ML layer architecture. HRMAS is an alternating two-step optimization process by which we mitigate the risk of network instability and performance degradation caused by architectural change by introducing a novel biologically-inspired "self-repairing" mechanism through intrinsic plasticity. The intrinsic plasticity is introduced to the second step of each HRMAS iteration and acts as unsupervised fast self-adaptation to structural and synaptic weight modifications introduced by the first step during the RSNN architectural "evolution." We demonstrate that the proposed automatic architecture optimization leads to significant performance gains over existing manually designed RSNNs: we achieve 96.44% on TI46-Alpha, 94.66% on N-TIDIGITS, 90.28% on DVS-Gesture, and 98.72% on N-MNIST. To the best of the authors' knowledge, this is the first work to perform systematic architecture optimization on RSNNs.

3.
Nat Neurosci ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977887

RESUMO

Coughing is a respiratory behavior that plays a crucial role in protecting the respiratory system. Here we show that the nucleus of the solitary tract (NTS) in mice contains heterogenous neuronal populations that differentially control breathing. Within these subtypes, activation of tachykinin 1 (Tac1)-expressing neurons triggers specific respiratory behaviors that, as revealed by our detailed characterization, are cough-like behaviors. Chemogenetic silencing or genetic ablation of Tac1 neurons inhibits cough-like behaviors induced by tussive challenges. These Tac1 neurons receive synaptic inputs from the bronchopulmonary chemosensory and mechanosensory neurons in the vagal ganglion and coordinate medullary regions to control distinct aspects of cough-like defensive behaviors. We propose that these Tac1 neurons in the NTS are a key component of the airway-vagal-brain neural circuit that controls cough-like defensive behaviors in mice and that they coordinate the downstream modular circuits to elicit the sequential motor pattern of forceful expiratory responses.

4.
New Phytol ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978318

RESUMO

Rare variants contribute significantly to the 'missing heritability' of quantitative traits. The genome-wide characteristics of rare variants and their roles in environmental adaptation of woody plants remain unexplored. Utilizing genome-wide rare variant association study (RVAS), expression quantitative trait loci (eQTL) mapping, genetic transformation, and molecular experiments, we explored the impact of rare variants on stomatal morphology and drought adaptation in Populus. Through comparative analysis of five world-wide Populus species, we observed the influence of mutational bias and adaptive selection on the distribution of rare variants. RVAS identified 75 candidate genes correlated with stomatal size (SS)/stomatal density (SD), and a rare haplotype in the promoter of serine/arginine-rich splicing factor PtoRSZ21 emerged as the foremost association signal governing SS. As a positive regulator of drought tolerance, PtoRSZ21 can recruit the core splicing factor PtoU1-70K to regulate alternative splicing (AS) of PtoATG2b (autophagy-related 2). The rare haplotype PtoRSZ21hap2 weakens binding affinity to PtoMYB61, consequently affecting PtoRSZ21 expression and SS, ultimately resulting in differential distribution of Populus accessions in arid and humid climates. This study enhances the understanding of regulatory mechanisms that underlie AS induced by rare variants and might provide targets for drought-tolerant varieties breeding in Populus.

5.
Biomed Pharmacother ; 177: 117046, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38981241

RESUMO

Neural stem cells (NSCs) exhibit a remarkable capacity for self-renewal and have the potential to differentiate into various neural lineage cells, which makes them pivotal in the management of neurological disorders. Harnessing the inherent potential of endogenous NSCs for enhancing nerve repair and regeneration represents an optimal approach to addressing diseases of the nervous system. In this study, we explored the potential of a novel benzophenone derivative named Digirseophene A (DGA), which was isolated from the endophytic fungus Corydalis tomentella. Previous experiments have extensively identified and characterized DGA, revealing its unique properties. Our findings demonstrate the remarkable capability of DGA to stimulate neural stem cell proliferation, both in vitro and in vivo. Furthermore, we established a model of radiation-induced cerebellar injury to assess the effects of DGA on the distribution of different cell subpopulations within the damaged cerebellum, thereby suggesting its beneficial role in cerebellar repair. In addition, our observations on a primary NSCs model revealed that DGA significantly increased cellular oxygen consumption, indicating increased energy and metabolic demands. By utilizing various pathway inhibitors in combination with DGA, we successfully demonstrated its ability to counteract the suppressive impacts of AMPK and GSK3ß inhibitors on NSC proliferation. Collectively, our research results strongly suggest that DGA, as an innovative compound, exerts its role in activating NSCs and promoting injury repair through the regulation of the AMPK/AKT/GSK3ß pathway.

6.
J Sep Sci ; 47(13): e2400308, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38982562

RESUMO

Jiawei Huoxiang Zhengqi Pill (JHZP) is a commonly used Chinese patent medicine for the clinical treatment of headache, dizziness, chest tightness as well as abdominal distension, and pain caused by wind-cold flu. In this study, a comprehensive strategy combining ultra-high performance liquid chromatography with diode array detector (UHPLC-DAD) fingerprinting and multi-component quantitative analysis was established and validated for quality evaluation of JHZP. A total of 49 characteristic common peaks were selected in a chromatographic fingerprinting study to assess the similarity of 15 batches of JHZP. Furthermore, 109 compounds were identified or preliminarily identified from JHZP by coupling with an advanced hybrid linear ion trap-Orbitrap mass spectrometer. For quantification, the optimized ultra-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method was employed for the simultaneous determination of 13 target compounds within 12 min. The sensitivity, precision, reproducibility, and accuracy of the method were satisfactory. This validated UPLC-MS/MS method was successfully applied to analyzing 15 batches of JHZP. The proposed comprehensive strategy combining UHPLC-DAD fingerprinting and multi-component UPLC-MS/MS analysis proved to be highly efficient, accurate, and reliable for the quality evaluation of JHZP, which can be considered as a reference for the overall quality evaluation of other Chinese herbal formulations.


Assuntos
Medicamentos de Ervas Chinesas , Controle de Qualidade , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química
7.
J Chromatogr A ; 1730: 465112, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38972253

RESUMO

A macrocyclic peptide A was successfully purified in large quantities (∼30 g) in >95 % purity by an integrated two-step orthogonal purification process combining supercritical fluid chromatography (SFC) with medium-pressure reverse-phase liquid chromatography (MP-RPLC). MP-RPLC was used to fractionate the crude peptide A, remove unwanted trifluoroacetic acid (TFA) originating from the peptide A cleavage off the resin, and convert the peptide A into ammonium acetate salt form, prior to the final purification by SFC. A co-solvent of methanol/acetonitrile containing ammonium acetate and water in CO2 was developed on a Waters BEH 2-Ethylpyridine column. The developed SFC method was readily scaled up onto a 5 cm diameter column to process multi-gram quantities of the MP-RPLC fraction to reach > 95 % purity with a throughput/productivity of 0.96 g/h. The incorporation of SFC with MP-RPLC has been demonstrated to have a broader application in other large-scale polypeptide purifications.

8.
Bioact Mater ; 40: 318-333, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38978805

RESUMO

Soft tissue integration around titanium (Ti) implants is weaker than that around natural teeth, compromising long-term success of Ti implants. Carbon monoxide (CO) possesses distinctive therapeutic properties, rendering it as a highly promising candidate for enhancing STI. However, achieving controlled CO generation at the STI interface remains challenging. Herein, a controlled CO-releasing dual-function coating was constructed on Ti surfaces. Under near-infrared (NIR) irradiation, the designed surface could actively accelerate CO generation for antibiosis against both aerobic and anaerobic bacteria. More importantly, in the absence of NIR, the slow release of CO induces macrophage polarization from pro-inflammatory phenotype towards pro-regenerative phenotype. In a rat implantation model with induced infection, the designed surface effectively controlled the bacterial infection, alleviates accompanying inflammation and modulated immune microenvironment, leading to enhanced STI. Single-cell sequencing revealed that the coating alters the cytokine profile within the soft tissue, thereby influencing cellular functions. Differentially expressed genes in macrophages are highly enriched in the PIK3-Akt pathway. Furthermore, the cellular communication between fibroblasts and macrophages was significantly enhanced through the CXCL12/CXCL14/CXCR4 and CSF1-CSF1R ligand-receptor pair. These findings indicate that our coating showed an appealing prospect for enhancing STI around Ti implants, which would ultimately contribute to the improved long-term success of Ti implants.

9.
Wideochir Inne Tech Maloinwazyjne ; 19(2): 223-232, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38973788

RESUMO

Introduction: Lateral lymph node dissection (LLND) has now been widely accepted as the optimal procedure to minimize lateral local recurrence (LLR) for selected cases with advanced lower rectal cancer in Asian countries. However, there is still controversy over the preservation or resection of the inferior vesical vessels (IVVs) during LLND due to concerns of impaired post-operative urinary function. Moreover, the standardized procedure for autonomic nerve preservation has not yet been established. Aim: To evaluate the early-stage postoperative voiding function in patients who underwent LLND with uni- versus bilateral resection of the IVVs and to introduce an autonomic nerve sparing technique with a fascial space priority approach (FSPA). Material and methods: LLND was performed in 106 consecutive patients with advanced low rectal cancer at Tianjin Union Medical Center from May 2017 to October 2022. Prospectively collected clinical data were retrospectively compared between patients who received uni-lateral and bilateral LLND. A video with narration was provided to introduce the stepwise procedure of autonomic nerve preservation during IVV resection. Results: The unilateral lymph node dissection (LND) group and the bilateral LND group included 75 and 31 cases, respectively. All LLNDs were performed with FSPA with IVV resection as a standard procedure. No significant differences were observed in overall catheterization days (p = 0.336) and re-catheterization rate (p = 0.575) between groups. No patients in either group suffered from long-term (≥ 30 days) voiding dysfunction. Conclusions: Autonomic nerve sparing is achievable with resection of IVVs during LLND. Satisfactory early-stage voiding function could be obtained with IVV resection on both sides.

10.
Gerontologist ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953432

RESUMO

BACKGROUND AND OBJECTIVES: This study examined day-to-day variation in care-resistant behaviors (CRBs) exhibited by persons living with dementia during mouth health care and the potential influence of time-of-day on CRB trajectories. RESEARCH DESIGN AND METHODS: A secondary analysis was conducted on a sample of 75 nursing home-dwelling persons living with dementia who exhibited CRBs during mouth care activities. Over 21 days, CRBs were measured using the revised Resistiveness to Care Scale (RTC-r) during morning and afternoon mouth care sessions. Group-based Trajectory Modeling was used to identify trajectory patterns and assess differences between morning and afternoon CRB patterns. RESULTS: Three trajectory patterns were identified: morning CRB trajectory patterns showed 50.6% of persons living with dementia had consistently low RTC-r scores, 37.5% of persons living with dementia exhibited fluctuating, moderate RTC-r scores, and 11.9% exhibited RTC-r scores that started high and then decreased over time. Similarly, CRB trajectory patterns during afternoon mouth care showed a consistently low RTC-r score for 54.5% and a fluctuating moderate RTC-r score for 38.6% of persons living with dementia. However, the third CRB trajectory group followed a high-increasing trajectory, with RTC-r scores starting high and continuing to increase for 6.9% of persons living with dementia. DISCUSSION AND IMPLICATIONS: CRBs are dynamic and vary within days and over time; however, the time of the day is often not considered in interventions to manage CRBs. Thus, it is important to consider the timing of providing mouth care for persons living with dementia. Based on the characteristics of the trajectories, we suggest that morning mouth activities may be more efficient.

15.
Inorg Chem ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39021089

RESUMO

The development of efficient and sustainable methods for reducing carbon dioxide (CO2) and converting it into valuable hydrocarbons has gained significant attention. In this study, researchers focused on Ti4+-doped metal-organic framework (MOF-74) photocatalysts. The incorporation of Ti4+ ions into the MOF-74 structure was achieved through a one-pot hydrothermal method. By replacing Zn2+ ions with Ti4+ ions in a substitutional manner, researchers have aimed to enhance the photocatalytic activity of the CO2 reduction. The obtained Ti4+-doped MOF-74 photocatalysts exhibited a significantly improved performance in the reduction of CO2 into carbon monoxide (CO). The doping of Ti4+ ions induced energy bands below the conduction band minimum (CBM) of MOF-74, extending the visible response range and enabling the photocatalysts to utilize a broader spectrum of light for catalytic reactions. This extension of the visible response range enables photocatalysts to utilize a broader spectrum of light for catalytic reactions. The incorporation of Ti4+ ions not only extends the visible response range but also suppresses charge carrier recombination. This work provides valuable insights into the design principles of MOF-based photocatalysts and paves the way for their practical implementation in addressing the energy crisis and reducing greenhouse gas emissions.

16.
Artigo em Inglês | MEDLINE | ID: mdl-39002105

RESUMO

OBJECTIVE: Development of a nomogram model for predicting the magnitude of risk of transferring hospitalized children with influenza to the ICU. METHODS: In a single-center retrospective study, 318 children with influenza who were hospitalized in our hospital from January 2018 to August 2023 were collected as study subjects. Children with influenza were randomly assigned to the training set and validation set in a ratio of 4:1. In the training set, risk factors were identified using univariate and multivariate logistic regression analyses, and a nomogram model was created on this basis. The validation set was used to evaluate the predictive power of the model. RESULTS: Multifactorial logistic regression analysis revealed six independent risk factors for transfer to the ICU in hospitalized children with influenza, including elevated peripheral white blood cell counts, elevated large platelet ratios, reduced mean platelet width, reduced complement C3, elevated serum globulin levels, and reduced total immunoglobulin M levels. Using these six metrics as predictors to construct a nomogram graphical model, the C-index was 0.970 (95% Cl: 0.953-0.988). The areas under the curve for the training and validation sets were 0.966 (95%Cl 0.947-0.985) and 0.919 (95%Cl 0.851-0.986), respectively. CONCLUSION: A nomogram for predicting the risk of transferring to the ICU for children with influenza was developed and validated, which demonstrates good calibration and clinical benefits.

17.
Exp Ther Med ; 28(3): 344, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39006457

RESUMO

Cyst excision and Roux-en-Y hepaticojejunostomy (RYHJ) is the standard treatment for choledochal cysts (CCs). In the present study, the results of totally laparoscopic surgery for CCs (TLCCs) in a pediatric population were evaluated. The clinical data of 28 children with CCs between June 2020 and June 2023 were retrospectively reviewed. All patients underwent TLCCs involving cyst excision and RYHJ. The jejunojejunal anastomosis was completed laparoscopically using manual sutures. Age at operation, operative time, postoperative recovery and complications were evaluated. The 28 patients comprised 8 boys and 20 girls who underwent TLCCs at a mean age of 4.2 years (range, 1 month-12.3 years) with a mean weight of 15.9 kg (range, 4.6-43 kg). All patients received ultrasound and magnetic resonance cholangiopancreatography examinations, which revealed a mean cyst diameter and length of 1.74±0.76 cm and 3.85±1.25 cm, respectively. The mean operative time was 214±43.8 min. The mean time until starting an oral diet after surgery was 2.89±1.23 days. Apart from bile leakage and wound infection, no other complications occurred during a median follow-up period of 18 months (range, 4-42 months). TLCCs can be performed safely by skilled surgeons in pediatric patients. TLCCs may be more physiologically compatible and accelerate recovery of intestinal function with reduced trauma and better esthetic outcomes than conventional laparoscopic surgery for CCs. Therefore, TLCCs with manual sutures may be considered as an option for minimally invasive surgery in pediatric patients with CCs.

18.
Sensors (Basel) ; 24(13)2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39001045

RESUMO

Nucleic acid tests are key tools for the detection and diagnosis of many diseases. In many cases, the amplification of the nucleic acids is required to reach a detectable level. To make nucleic acid amplification tests more accessible to a point-of-care (POC) setting, isothermal amplification can be performed with a simple heating source. Although these tests are being performed in bulk reactions, the quantification is not as accurate as it would be with digital amplification. Here, we introduce the use of the vibrating sharp-tip capillary for a simple and portable system for tunable on-demand droplet generation. Because of the large range of droplet sizes possible and the tunability of the vibrating sharp-tip capillary, a high dynamic range (~2 to 6000 copies/µL) digital droplet loop-mediated isothermal amplification (ddLAMP) system has been developed. It was also noted that by changing the type of capillary on the vibrating sharp-tip capillary, the same mechanism can be used for simple and portable DNA fragmentation. With the incorporation of these elements, the present work paves the way for achieving digital nucleic acid tests in a POC setting with limited resources.


Assuntos
Técnicas de Amplificação de Ácido Nucleico , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Vibração , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Ácidos Nucleicos/análise , DNA/análise , DNA/genética , DNA/química
19.
Nanomaterials (Basel) ; 14(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38998702

RESUMO

Acetone is a biomarker found in the expired air of patients suffering from diabetes. Therefore, early and accurate detection of its concentration in the breath of such patients is extremely important. We prepared Tin(IV) oxide (SnO2) nanospheres via hydrothermal treatment and then decorated them with bimetallic PtAu nanoparticles (NPs) employing the approach of in situ reduction. The topology, elemental composition, as well as crystal structure of the prepared materials were studied via field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The findings revealed that bimetallic PtAu-decorated SnO2 nanospheres (PtAu/SnO2) were effectively synthesized as well as PtAu NPs evenly deposited onto the surface of the SnO2 nanospheres. Pure SnO2 nanospheres and PtAu/SnO2 sensors were prepared, and their acetone gas sensitivity was explored. The findings demonstrated that in comparison to pristine SnO2 nanosphere sensors, the sensors based on PtAu/SnO2 displayed superior sensitivity to acetone of 0.166-100 ppm at 300 °C, providing a low theoretical limit of detection equal to 158 ppm. Moreover, the PtAu/SnO2 sensors showed excellent gas response (Ra/Rg = 492.3 to 100 ppm), along with fast response and recovery (14 s/13 s to 10 ppm), good linearity of correlation, excellent repeatability, long-term stability, and satisfactory selectivity at 300 °C. This improved gas sensitivity was because of the electron sensitization of the Pt NPs, the chemical sensitization of the Au NPs, as well as the synergistic effects of bimetallic PtAu. The PtAu/SnO2 sensors have considerable potential for the early diagnosis and screening of diabetes.

20.
Molecules ; 29(13)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38999139

RESUMO

With the intensification of the energy crisis, it is urgent to vigorously develop new environment-friendly energy storage materials. In this work, coexisting ferroelectric and relaxor-ferroelectric phases at a nanoscale were constructed in Sr(Zn1/3Nb2/3)O3 (SZN)-modified (Bi0.5Na0.5)0.94Ba0.06TiO3 (BNBT) ceramics, simultaneously contributing to large polarization and breakdown electric field and giving rise to a superior energy storage performance. Herein, a high recoverable energy density (Wrec) of 5.0 J/cm3 with a conversion efficiency of 82% at 370 kV/cm, a practical discharged energy density (Wd) of 1.74 J/cm3 at 230 kV/cm, a large power density (PD) of 157.84 MW/cm3, and an ultrafast discharge speed (t0.9) of 40 ns were achieved in the 0.85BNBT-0.15SZN ceramics characterized by the coexistence of a rhombohedral-tetragonal phase (ferroelectric state) and a pseudo-cubic phase (relaxor-ferroelectric state). Furthermore, the 0.85BNBT-0.15SZN ceramics also exhibited excellent temperature stability (25-120 °C) and cycling stability (104 cycles) of their energy storage properties. These results demonstrate the great application potential of 0.85BNBT-0.15SZN ceramics in capacitive pulse energy storage devices.

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