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1.
Microorganisms ; 12(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38930523

RESUMO

Babesia duncani (B. duncani), a protozoan parasite prevalent in North America, is a significant threat for human health. Given the regulatory role of pyruvate kinase I (PyK I) in glycolytic metabolism flux and ATP generation, PyK I has been considered the target for drug intervention for a long time. In this study, B. duncani PyK I (BdPyK I) was successfully cloned, expressed, and purified. Polyclonal antibodies were confirmed to recognize the native BdPyK I protein (56 kDa) using Western blotting. AlphaFold software predicted the three-dimensional structure of BdPyK I, and molecular docking with small molecules was conducted to identify potential binding sites of inhibitor on BdPyK I. Moreover, inhibitory effects of six inhibitors (tannic acid, apigenin, shikonin, PKM2 inhibitor, rosiglitazone, and pioglitazone) on BdPyK I were examined under the optimal enzymatic conditions of 3 mM PEP and 3 mM ADP, and significant activity reduction was found. Enzyme kinetics and growth inhibition assays further confirmed the reliability of these inhibitors, with PKM2 inhibitor, tannic acid, and apigenin exhibiting the highest selectivity index as specific inhibitors for B. duncani. Subsequently, key amino acid residues were mutated in both BdPyK I and Homo sapiens pyruvate kinase I (HPyK I), and two differential amino acid residues (isoleucine and phenylalanine) were identified between HPyK I and BdPyK I through PyK activity detection experiments. These findings lay foundation for understanding the role of PyK I in the growth and development of B. duncani, providing insights for babesiosis prevention and drug development.

2.
Adv Healthc Mater ; : e2401609, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888934

RESUMO

Photothermal therapy (PTT) is a promising approach for tumor ablation and cancer treatment. However, controlling the therapeutic temperature during treatment remains challenging, and imprecise thermal regulation can harm adjacent healthy tissues, reduce therapeutic accuracy, and promote the thermotolerance of cellular phenotypes, potentially leading to tumor invasion and recurrence. Although existing methods provide basic temperature control by adjusting irradiation power and photothermal agent dosing, they lack real-time temperature monitoring and feedback control capabilities, underscoring the urgent need for more integrated and precise PTT systems. In this context, an innovative photothermoelectric (PTE) cobalt-infused chitosan (CS) nanocomposite hydrogel (PTE-Co@CS) is developed for precise temperature-regulated PTT, exhibiting desirable mechanical properties and exceptional biocompatibility. Enhanced by embedded nanoparticles, PTE-Co@CS demonstrates superior photothermal conversion efficiency compared with existing methods, while also featuring thermoelectric responsiveness and increased sensitivity to photostimuli. Its advantageous PTE response characteristics ensure a linear correlation between temperature shifts and resistance changes (e.g., R2 = 0.99919 at 0.5 W cm⁻2), enabling synchronized qualitative and quantitative control of PTT temperature through electrical signal monitoring. This allows for real-time monitoring and regulation during PTT, effectively addressing the issue of uncontrollable temperatures and improving therapeutic efficacy.

3.
Arch Pharm Res ; 47(5): 410-441, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38750332

RESUMO

The genus Tamarix in the Tamaricaceae family consists of more than 100 species of halophyte plants worldwide that are mainly used to improve saline-alkali land and for coastal windbreaks, sand fixation, and afforestation in arid areas. A considerable number of species in this genus are also used as traditional medicines to treat various human diseases, especially in Asian and African countries. This review presents a comprehensive summary of 655 naturally occurring compounds derived from the genus Tamarix, categorized into flavonoids (18.0%), phenols (13.9%), tannins (9.3%), terpenoids (10.5%), essential oils (31.0%), and others (17.3%). The investigation revealed that the crude extracts and phytochemicals of this genus exhibited significant therapeutic potential, including anti-inflammatory, anti-Alzheimer, anticancer, antidiabetic, antibacterial, and antifungal activities. Six species of Tamarix have anticancer effects by causing cancer cell death, inducing autophagy, and stopping cell division. Seven species from the same genus have the potential for treating diabetes by inhibiting α-glycosidase activity, suppressing human islet amyloid polypeptide, regulating blood glucose levels, and modulating autophagy or inflammation. The focus on antibacterial and antidiabetic effects is due to the presence of volatile oil and flavonoid components. Extensive research has been conducted on the biological activity of 30 constituents, including 15 flavonoids, 5 phenols, 3 terpenoids, 1 tannin, and 6 others. Therefore, future research should thoroughly study the mechanisms of action of these and similar compounds. This is the most comprehensive review of the phytochemistry and pharmacological properties of Tamarix species, with a critical assessment of the current state of knowledge.


Assuntos
Compostos Fitoquímicos , Tamaricaceae , Humanos , Tamaricaceae/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/química , Animais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/química
4.
Artigo em Inglês | MEDLINE | ID: mdl-38631552

RESUMO

BACKGROUND: Predicting cognitive decline among individuals in the aging population who are already amyloid-ß (Aß) positive or tau positive poses clinical challenges. In Alzheimer's disease research, intra-default mode network (DMN) connections play a pivotal role in diagnosis. In this article, we propose metabolic connectivity within the DMN as a supplementary biomarker to the Aß, pathological tau, and neurodegeneration framework. METHODS: Extracting data from 1292 participants in the Alzheimer's Disease Neuroimaging Initiative, we collected paired T1-weighted structural magnetic resonance imaging and 18F-labeled-fluorodeoxyglucose positron emission computed tomography scans. Individual metabolic DMN networks were constructed, and metabolic connectivity (MC) strength in the DMN was assessed. In the cognitively unimpaired group, the Cox model identified cognitively unimpaired (MC+), high-risk participants, with Kaplan-Meier survival analyses and hazard ratios revealing the strength of MC's predictive performance. Spearman correlation analyses explored relationships between MC strength, and Aß, pathological tau, neurodegeneration biomarkers, and clinical scales. DMN standard uptake value ratio (SUVR) provided comparative insights in the analyses. RESULTS: Both MC strength and SUVR exhibited gradual declines with cognitive deterioration, displaying significant intergroup differences. Survival analyses indicated enhanced Aß and tau prediction with both metrics, with MC strength outperforming SUVR. Combined MC strength and Aß yielded optimal predictive performance (hazard ratio = 9.29), followed by MC strength and tau (hazard ratio = 8.92). Generally, the strength of MC's correlations with Aß, pathological tau, and neurodegeneration biomarkers exceeded SUVR. CONCLUSIONS: Individuals with normal cognition and disrupted DMN metabolic connectivity face an elevated risk of cognitive decline linked to Aß that precedes metabolic issues.


Assuntos
Doença de Alzheimer , Rede de Modo Padrão , Progressão da Doença , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Masculino , Feminino , Idoso , Rede de Modo Padrão/diagnóstico por imagem , Rede de Modo Padrão/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Proteínas tau/metabolismo , Biomarcadores/metabolismo
5.
Healthc Technol Lett ; 11(2-3): 167-178, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638496

RESUMO

Root canal therapy (RCT) is a widely performed procedure in dentistry, with over 25 million individuals undergoing it annually. This procedure is carried out to address inflammation or infection within the root canal system of affected teeth. However, accurately aligning CT scan information with the patient's tooth has posed challenges, leading to errors in tool positioning and potential negative outcomes. To overcome these challenges, a mixed reality application is developed using an optical see-through head-mounted display (OST-HMD). The application incorporates visual cues, an augmented mirror, and dynamically updated multi-view CT slices to address depth perception issues and achieve accurate tooth localization, comprehensive canal exploration, and prevention of perforation during RCT. Through the preliminary experimental assessment, significant improvements in the accuracy of the procedure are observed. Specifically, with the system the accuracy in position was improved from 1.4 to 0.4 mm (more than a 70% gain) using an Optical Tracker (NDI) and from 2.8 to 2.4 mm using an HMD, thereby achieving submillimeter accuracy with NDI. 6 participants were enrolled in the user study. The result of the study suggests that the average displacement on the crown plane of 1.27 ± 0.83 cm, an average depth error of 0.90 ± 0.72 cm and an average angular deviation of 1.83 ± 0.83°. Our error analysis further highlights the impact of HMD spatial localization and head motion on the registration and calibration process. Through seamless integration of CT image information with the patient's tooth, our mixed reality application assists dentists in achieving precise tool placement. This advancement in technology has the potential to elevate the quality of root canal procedures, ensuring better accuracy and enhancing overall treatment outcomes.

6.
Adv Healthc Mater ; 13(17): e2303921, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38341619

RESUMO

Wearable epidermal electronics with non- or minimally-invasive characteristics can collect, transduce, communicate, and interact with accessible physicochemical health indicators on the skin. However, due to the stratum corneum layer, rich information about body health is buried under the skin stratum corneum layer, for example, in the skin interstitial fluid. Microneedle patches are typically designed with arrays of special microsized needles of length within 1000 µm. Such characteristics potentially enable the access and sample of biomolecules under the skin or give therapeutical treatment painlessly and transdermally. Integrating microneedle patches with various electronics allows highly efficient transdermal bioelectronics, showing their great promise for biomedical and healthcare applications. This comprehensive review summarizes and highlights the recent progress on integrated transdermal bioelectronics based on microneedle patches. The design criteria and state-of-the-art fabrication techniques for such devices are initially discussed. Next, devices with different functions, including but not limited to health monitoring, drug delivery, and therapeutical treatment, are highlighted in detail. Finally, key issues associated with current technologies and future opportunities are elaborated to sort out the state of recent research, point out potential bottlenecks, and provide future research directions.


Assuntos
Agulhas , Humanos , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Administração Cutânea , Dispositivos Eletrônicos Vestíveis , Nanomedicina Teranóstica/métodos , Pele/metabolismo , Animais
7.
J Craniofac Surg ; 35(4): e316-e321, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38421202

RESUMO

OBJECTIVE: The decision to retain or extract teeth in the line of mandibular fractures has been a subject of debate in much of the scientific literature, and there is a need for further evidence to clear this issue. Thus, the aim of this study was to investigate both the positive and negative effects of teeth in the line of mandibular fractures provide more evidence in this field, as well as take into consideration patients' quality of life after the surgery. METHODS: Patients after trauma with teeth in the line of mandibular fractures were included in this study. Open reduction and rigid internal fixation, elastic intermaxillary reduction were expected to achieve a satisfactory occlusion and/or anatomical reduction in the fragments as assessed by orthopantomogram, computed tomography scans, and clinical examination. The remaining cases had maxillomandibular fixation (MMF) with an arch bar and bridle wire. All the patients included in this study will take the Visual Analog Scale score evaluation before and after surgery subjectively to further verify the impact on their life qualify, as well as the further treatment needed. RESULTS: A total of 78 patients with teeth in the line of mandibular fractures were included in this study. Open reduction and rigid internal fixation was used in 37 patients, whereas another 35 patients accepted elastic intermaxillary reduction. Six cases underwent MMF. The number of involved teeth was 83. Three of the 83 teeth involved in the fracture lines healed with complications. In the cases where the teeth had been removed before fracture treatment, or in cases of delayed extractions, no complications were noted. The majority of the patients felt good about the whole treatment, however, 4 in the MMF group complained about worry about their oral health due to MMF leading to mouth open limitation. CONCLUSION: The factors that should be considered for removal include the condition of the teeth and alveolar bone, the timing and the type of treatment, as well as the patients' desire, if possible. This is an individual-based decision that needs to consider more objective and subjective potential risks to avoid complications.


Assuntos
Fixação Interna de Fraturas , Fraturas Mandibulares , Qualidade de Vida , Radiografia Panorâmica , Humanos , Fraturas Mandibulares/cirurgia , Fraturas Mandibulares/diagnóstico por imagem , Masculino , Feminino , Fixação Interna de Fraturas/métodos , Adulto , Tomografia Computadorizada por Raios X , Técnicas de Fixação da Arcada Osseodentária , Extração Dentária , Pessoa de Meia-Idade , Resultado do Tratamento , Traumatismos Dentários , Redução Aberta/métodos
8.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38037857

RESUMO

Repetitive transcranial magnetic stimulation (rTMS) and cognitive training for patients with Alzheimer's disease (AD) can change functional connectivity (FC) within gray matter (GM). However, the role of white matter (WM) and changes of GM-WM FC under these therapies are still unclear. To clarify this problem, we applied 40 Hz rTMS over angular gyrus (AG) concurrent with cognitive training to 15 mild-moderate AD patients and analyzed the resting-state functional magnetic resonance imaging before and after treatment. Through AG-based FC analysis, corona radiata and superior longitudinal fasciculus (SLF) were identified as activated WM tracts. Compared with the GM results with AG as seed, more GM regions were found with activated WM tracts as seeds. The averaged FC, fractional amplitude of low-frequency fluctuation (fALFF), and regional homogeneity (ReHo) of the above GM regions had stronger clinical correlations (r/P = 0.363/0.048 vs 0.299/0.108, 0.351/0.057 vs 0.267/0.153, 0.420/0.021 vs 0.408/0.025, for FC/fALFF/ReHo, respectively) and better classification performance to distinguish pre-/post-treatment groups (AUC = 0.91 vs 0.88, 0.65 vs 0.63, 0.87 vs 0.82, for FC/fALFF/ReHo, respectively). Our results indicated that rTMS concurrent with cognitive training could rewire brain network by enhancing GM-WM FC in AD, and corona radiata and SLF played an important role in this process.


Assuntos
Doença de Alzheimer , Substância Branca , Humanos , Substância Cinzenta/patologia , Substância Branca/patologia , Estimulação Magnética Transcraniana , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/terapia , Doença de Alzheimer/patologia , Treino Cognitivo , Imageamento por Ressonância Magnética/métodos , Encéfalo
9.
Front Neurosci ; 17: 1234477, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37650097

RESUMO

Background: The aim of this study was to investigate the functional abnormalities between the nucleus accumbens (NAc) and the whole brain in individuals with Insomnia Disorder (ID) using resting-state functional magnetic resonance imaging (fMRI). Additionally, the study aimed to explore the underlying neural mechanisms of ID. Methods: We enrolled 18 participants with ID and 16 normal controls (NC). Resting-state functional connectivity (FC) between the NAc and the whole brain voxels was calculated and compared between the two groups to identify differential brain region. Receiver operating characteristic (ROC) curve analysis was employed to assess the ability of differential features to distinguish between groups. Furthermore, Pearson correlation analysis was performed to examine the relationship between neurocognitive scores and differential features. Results: The ID group exhibited significantly reduced FC values in several brain regions, including the right supplementary motor area, the bilateral middle frontal gyrus, the bilateral median cingulate and paracingulate gyri and the left precuneus. The area under the curve (AUC) of the classification model based on FC in these brain regions was 83.3%. Additionally, the abnormal functional changes observed in ID patients were positively correlated with the Fatigue Severity Scale (R = 0.650, p = 0.004). Conclusion: These findings suggest that the NAc may play a crucial role in the diagnosis of ID and could serve as a potential imaging biomarker, providing insights into the underlying neural mechanisms of the disorder.

10.
FEBS Open Bio ; 13(11): 2020-2034, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37606998

RESUMO

Neuropathic pain (NP), resulting from nerve injury, alters neural plasticity in spinal cord and brain via the release of inflammatory mediators. The remodeling of store-operated calcium entry (SOCE) involves the refilling of calcium in the endoplasmic reticulum via STIM1 and Orai1 proteins and is crucial for maintaining neural plasticity and neurotransmitter release. The mechanism underlying SOCE-mediated NP remains largely unknown. In this study, we found SOCE-mediated calcium refilling was significantly higher during neuropathic pain, and the major component Orai1 was specifically co-localized with neuronal markers. Intrathecal injection of SOCE antagonist SKF96365 remarkably alleviated nerve injury- and formalin-induced pain and suppressed c-Fos expression in response to innocuous mechanical stimulation. RNA sequencing revealed that SKF96365 altered the expression of spinal transcription factors, including Fos, Junb, and Socs3, during neuropathic pain. In order to identify the genes critical for SKF96365-induced effects, we performed weighted gene co-expression network analysis (WGCNA) to identify the genes most correlated with paw withdrawal latency phenotypes. Of the 16 modules, MEsalmon module was the most highly correlated with SKF96365 induced effects. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the enriched genes of MEsalmon module were significantly related to Toll-like receptor signaling, steroid biosynthesis, and chemokine signaling, which may mediate the analgesic effect caused by SKF9636 treatment. Additionally, the SOCE antagonist YM-58483 produced similar analgesic effects in nerve injury- and formalin-induced pain. Our results suggest that manipulation of spinal SOCE signaling might be a promising target for pain relief by regulating neurotransmitter production and spinal transcription factor expression.


Assuntos
Canais de Cálcio , Neuralgia , Humanos , Canais de Cálcio/genética , Cálcio/metabolismo , Células Cultivadas , Neuralgia/tratamento farmacológico , Fatores de Transcrição/metabolismo , Formaldeído , Neurotransmissores , Analgésicos
11.
Environ Pollut ; 316(Pt 1): 120710, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36414162

RESUMO

The atmospheric chemistry of nitrous acid (HONO) has received extensive attention because of its significant contribution to hydroxyl (OH) radicals. Heterogeneous reaction of NO2 is an important HONO source, and its reaction mechanism is affected by many factors, such as concentration of gaseous NO2, surface adsorbed water, relative humidity and temperature. Although laboratory studies have confirmed the effect of temperature on heterogeneous reaction of NO2, there are few field observations reporting about it. We have conducted a field observation in the early spring 2021 when the temperature ranges widely (-0.1-24.7 °C). Concentrations of HONO and related pollutants at the urban area of Beijing are obtained. The hourly averaged HONO concentration reaches 4.87 ppb with a mean value of 1.48 ± 1.09 ppb. Combined with box model and RACM2 mechanism, we found an optimal temperature (∼10 °C) existing for heterogeneous reaction of NO2 during this measurement. When considering the promotion effect of optimal temperature, the contribution of heterogeneous reaction of NO2 to HONO can increase by 10%. This result will provide essential information for developing an accurate model of HONO chemistry in the atmosphere especially for certain periods or regions with temperature changing largely. Moreover, heterogeneous reaction of NO2 is the vital source of HONO, contributing 63-76% to simulated HONO during this measurement. Note that HONO photolysis is the most important formation pathway of OH radicals, and ambient HONO concentration is the obbligato constraint for evaluating atmospheric oxidation by model simulations.


Assuntos
Ácido Nitroso , Ozônio , Radical Hidroxila , Dióxido de Nitrogênio , Pequim
12.
J Environ Sci (China) ; 124: 557-569, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182163

RESUMO

Atmospheric oxidizing capacity (AOC) is the fundamental driving factors of chemistry process (e.g., the formation of ozone (O3) and secondary organic aerosols (SOA)) in the troposphere. However, accurate quantification of AOC still remains uncertainty. In this study, a comprehensive field campaign was conducted during autumn 2019 in downtown of Beijing, where O3 and PM2.5 episodes had been experienced successively. The observation-based model (OBM) is used to quantify the AOC at O3 and PM2.5 episodes. The strong intensity of AOC is found at O3 and PM2.5 episodes, and hydroxyl radical (OH) is the dominating daytime oxidant for both episodes. The photolysis of O3 is main source of OH at O3 episode; the photolysis of nitrous acid (HONO) and formaldehyde (HCHO) plays important role in OH formation at PM2.5 episode. The radicals loss routines vary according to precursor pollutants, resulting in different types of air pollution. O3 budgets and sensitivity analysis indicates that O3 production is transition regime (both VOC and NOx-limited) at O3 episode. The heterogeneous reaction of hydroperoxy radicals (HO2) on aerosol surfaces has significant influence on OH and O3 production rates. The HO2 uptake coefficient (γHO2) is the determining factor and required accurate measurement in real atmospheric environment. Our findings could provide the important bases for coordinated control of PM2.5 and O3 pollution.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Aerossóis/análise , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental , Formaldeído , Radical Hidroxila/análise , Ácido Nitroso , Oxidantes , Oxirredução , Ozônio/análise , Material Particulado/análise , Compostos Orgânicos Voláteis/análise
13.
Foods ; 11(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36429144

RESUMO

In this study, caffeic acid (CA) and chlorogenic acid (CGA) were incorporated onto chitosan (CS) using free radical grafting initiated by a hydrogen peroxide/ascorbic acid (H2O2/Vc) redox system. The structural properties of the CA (CA-g-CS) and CGA (CGA-g-CS) derivatives were characterized by UV-Vis absorption, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), nuclear magnetic resonance (NMR), and thermal stability analysis. Then, the antioxidant and antibacterial properties were evaluated, and the effect of CGA-g-CS on the postharvest quality of Saimaiti apricot was studied. It proved that phenolic acids were successfully grafted onto the CS. The grafting ratios of CA-g-CS and CGA-g-CS were 126.21 mg CAE/g and 148.94 mg CGAE/g. The antioxidation and antibacterial activities of CGA-g-CS were better than those of CA-g-CS. The MICs of CGA-g-CS against E. coli, S. aureus, and B. subtilis were 2, 1, and 2 mg/mL. The inhibitory zones of 20 mg/mL CGA-g-CS against the three bacteria were 19.16 ± 0.35, 16.33 ± 0.91, and 16.24 ± 0.05 mm. The inhibitory effects of 0.5% CGA-g-CS on the firmness, weight loss, SSC, TA, relative conductivity, and respiration rate of the apricot were superior. Our results suggest that CGA-g-CS can be potentially used as an edible coating material to preserve apricots.

14.
Opt Express ; 30(10): 16479-16488, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221489

RESUMO

We present an efficient tunable optical parametric generator (OPG) with its linewidth close to the Fourier transform limit by injection seeding a tunable diode laser. Benefitting from high-peak-power sub-nanosecond (426 ps) laser pumping and a high-gain MgO:PPLN (PPMgLN) crystal, the OPG produced signal peak power up to 0.343 MW at 1638 nm and the total conversion efficiency reached 47.9% at 1-kHz pulse repetition rate. Considering the linewidth limit of short signal pulses (∼ 350 ps), a tunable seeder with the linewidth at hundred-MHz level was applicable. The achieved OPG signal tuning range was 1510-1638 nm with linewidth at GHz level, which is two orders of magnitude narrower than the unseeded OPG. Injection seeding a non-resonant OPG device does not introduce extra cavity feedback electronics that are essential for an optical parametric oscillator (OPO), greatly improving robustness and reducing cost. It is believed such a compact, tunable and costless PPMgLN OPG with high peak power, high repetition rate and relatively narrow linewidth has great significance in lidar, spectroscopy, etc.

15.
Front Microbiol ; 13: 862894, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814662

RESUMO

Babesia microti is an obligate intraerythrocytic protozoan transmitted by an Ixodes tick. Infections caused by protozoa, including Plasmodium yoelii and Toxoplasma gondii, are shown to inhibit tumor development by activating immune responses. Th1 immune response and macrophages not only are essential key factors in Babesia infection control but also play an important role in regulating tumor development. In this study, we investigated the effects of B. microti infection on melanoma in tumor-bearing mice. The results showed that B. microti infection could inhibit the growth of melanoma, significantly enlarge the spleen size (p ≤ 0.0001), and increase the survival period (over 7 days) of tumor-bearing mice. Mouse spleen immune cell analysis revealed that B. microti-infected tumor-bearing mice could increase the number of macrophages and CD4+ T cells, as well as the proportion of CD4+ T cells and M1 macrophages in the tumor. Immunohistochemical assays showed that B. microti infection could inhibit tumor angiogenesis (p ≤ 0.0032). Meanwhile, both B. microti-infected erythrocytes and culture supernatant were observed to significantly (p ≤ 0.0021) induce the mRNA expression of iNOS, IL-6, and TNF-α in macrophages. Moreover, B. microti culture supernatant could also repolarize IL-4-induced M2 macrophages to the M1 type. Overall, B. microti exerted antitumor effects by stimulating the immune system of tumor-bearing mice and inducing the polarization of immunosuppressive M2 macrophages to pro-inflammatory M1 macrophages.

16.
J Environ Sci (China) ; 114: 343-353, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35459497

RESUMO

As an important precursor of hydroxyl radical (OH), nitrous acid (HONO) plays a significant role in atmospheric chemistry. Here, an observation of HONO and relevant air pollutants in an urban site of Beijing from 14 to 28 April, 2017 was performed. Two distinct peaks of HONO concentrations occurred during the observation. In contrast, the concentration of particulate matter in the first period (period Ⅰ) was significantly higher than that in the second period (period Ⅱ). Comparing to HONO sources in the two periods, we found that the direct vehicle emission was an essential source of the ambient HONO during both periods at night, especially in period Ⅱ. The heterogeneous reaction of NO2 was the dominant source in period Ⅰ, while the homogeneous reaction of NO with OH was more critical source at night in period Ⅱ. In the daytime, the heterogeneous reaction of NO2 was a significant source and was confirmed by the good correlation coefficients (R2) between the unknown sources (Punknown) with NO2, PM2.5, NO2 × PM2.5 in period Ⅰ. Moreover, when solar radiation and OH radicals were considered to explore unknown sources in the daytime, the enhanced correlation of Punknown with photolysis rate of NO2 and OH ( [Formula: see text]  × OH) were 0.93 in period Ⅰ, 0.95 in period Ⅱ. These excellent correlation coefficients suggested that the unknown sources released HONO highly related to the solar radiation and the variation of OH radicals.


Assuntos
Dióxido de Nitrogênio , Ácido Nitroso , Pequim , Ácido Nitroso/análise , Material Particulado , Emissões de Veículos
17.
J Environ Sci (China) ; 114: 85-97, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35459517

RESUMO

The field observation of 54 non-methane hydrocarbon compounds (NMHCs) was conducted from September 1 to October 20 in 2020 during autumn in Haidian District, Beijing. The mean concentration of total NMHCs was 29.81 ± 11.39 ppbv during this period, and alkanes were the major components. There were typical festival effects of NMHCs with lower concentration during the National Day. Alkenes and aromatics were the dominant groups in ozone formation potential (OFP) and OH radical loss rate (LOH). The positive matrix factorization (PMF) running results revealed that vehicular exhaust became the biggest source in urban areas, followed by liquefied petroleum gas (LPG) usage, solvent usage, and fuel evaporation. The box model coupled with master chemical mechanism (MCM) was applied to study the impacts of different NMHCs sources on ozone (O3) formation in an O3 episode. The simulation results indicated that reducing NMHCs concentration could effectively suppress O3 formation. Moreover, reducing traffic-related emissions of NMHCs was an effective way to control O3 pollution at an urban site in Beijing.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental/métodos , Hidrocarbonetos/análise , Metano , Ozônio/análise , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
18.
Poult Sci ; 101(6): 101863, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35489250

RESUMO

To investigate the pivotal roles of the duck plague virus (DPV) tegument protein UL14 in viral replication, we generated 2 mutated viruses of DPV by using the bacterial artifcial chromosome system, the UL14-null mutant virus (CHv-BAC-ΔUL14) and the corresponding revertant virus (CHv-BAC-ΔUL14R). We found that the CHv-BAC-ΔUL14 viruses exhibited impaired virion morphogenesis in transmission electron microscopy (TEM) studies. Furthermore, CHv-BAC-ΔUL14 exhibited a plaque size reduction in duck embryo fibroblasts (DEFs). Finally, CHv-BAC-ΔUL14 exhibited a significant viral growth defect. Taken together, our findings suggest that DPV UL14 protein regulates viral morphogenesis for efficient viral replication.


Assuntos
Galinhas , Patos , Animais , Mardivirus , Morfogênese , Vírion , Replicação Viral
19.
Colloids Surf B Biointerfaces ; 212: 112358, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35101822

RESUMO

Two-dimensional (2D) colloidal crystals are ordered monolayer arrays of colloidal sphere particles assembled on the substrates or at phase interfaces. Owing to their unique periodic structure and fascinating properties, 2D colloidal crystals have aroused considerable interest because of their potential applications. Among them, 2D colloidal crystals self-assembled from soft microgel spheres stand out particularly. The 2D colloidal crystals of soft microgel spheres combine the advantages of monolayer colloidal crystals and sensitive microgels, which have a good application prospect in biomedical area. In this article, we provide a systematic overview of 2D colloidal crystals of soft microgel spheres related to their development, preparation and applications. First, various preparation methods of 2D colloidal crystal of microgels are introduced, including dip-coating, drop-coating, spin-coating, interface assembly, surface reaction-assisted assembly, and so forth. Second, representative biomedical applications consisting of optical sensor, drug delivery, antibacterial coating, cell culture, and colloidal template are also exemplified to show the high performance of 2D colloidal crystals of soft microgel spheres. In addition, we also present prospects of future developments of 2D microgel colloidal crystals.


Assuntos
Microgéis , Coloides/química , Sistemas de Liberação de Medicamentos
20.
Front Microbiol ; 12: 710678, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603237

RESUMO

The apicomplexan Babesia microti is a main pathogenic parasite causing human babesiosis, which is one of the most widely distributed tick-borne diseases in humans. Pyruvate kinase (PYK) plays a central metabolic regulatory role in most living organisms and catalyzes the essentially irreversible step in glycolysis that converts phosphoenolpyruvate (PEP) to pyruvate. Hence, PYK is recognized as an attractive therapeutic target in cancer and human pathogens such as apicomplexans. In this study, we cloned, expressed, and purified B. microti PYK I (BmPYKI). Western blotting illustrated that anti-rBmPYKI antibody could specifically recognize the native BmPYKI protein in the lysate of B. microti with a 54-kDa band, which is consistent with the predicted size. In addition, the enzymatic activity of the purified recombinant PYKI (rPYKI) was tested under a range of pH values. The results showed that the maximum catalytic activity could be achieved at pH 7.0. The saturation curves for substrates demonstrated that the K m value for PEP was 0.655 ± 0.117 mM and that for ADP was 0.388 ± 0.087 mM. We further investigated the effect of 13 compounds on rBmPYKI. Kinetic analysis indicated that six inhibitors (tannic acid, shikonin, apigenin, PKM2 inhibitor, rosiglitazone, and pioglitazone) could significantly inhibit the catalytic activity of PYKI, among which tannic acid is the most efficient inhibitor with an IC50 value 0.49 µM. Besides, four inhibitors (tannic acid, apigenin, shikonin, and PKM2 inhibitor) could significantly decrease the growth of in vitro-cultured B. microti with IC50 values of 0.77, 2.10, 1.73, and 1.15 µM. Overall, the present study provides a theoretical basis for the design and development of new anti-Babesia drugs.

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