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1.
BMC Med ; 22(1): 56, 2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317226

RESUMO

BACKGROUND: A comprehensive overview of artificial intelligence (AI) for cardiovascular disease (CVD) prediction and a screening tool of AI models (AI-Ms) for independent external validation are lacking. This systematic review aims to identify, describe, and appraise AI-Ms of CVD prediction in the general and special populations and develop a new independent validation score (IVS) for AI-Ms replicability evaluation. METHODS: PubMed, Web of Science, Embase, and IEEE library were searched up to July 2021. Data extraction and analysis were performed for the populations, distribution, predictors, algorithms, etc. The risk of bias was evaluated with the prediction risk of bias assessment tool (PROBAST). Subsequently, we designed IVS for model replicability evaluation with five steps in five items, including transparency of algorithms, performance of models, feasibility of reproduction, risk of reproduction, and clinical implication, respectively. The review is registered in PROSPERO (No. CRD42021271789). RESULTS: In 20,887 screened references, 79 articles (82.5% in 2017-2021) were included, which contained 114 datasets (67 in Europe and North America, but 0 in Africa). We identified 486 AI-Ms, of which the majority were in development (n = 380), but none of them had undergone independent external validation. A total of 66 idiographic algorithms were found; however, 36.4% were used only once and only 39.4% over three times. A large number of different predictors (range 5-52,000, median 21) and large-span sample size (range 80-3,660,000, median 4466) were observed. All models were at high risk of bias according to PROBAST, primarily due to the incorrect use of statistical methods. IVS analysis confirmed only 10 models as "recommended"; however, 281 and 187 were "not recommended" and "warning," respectively. CONCLUSION: AI has led the digital revolution in the field of CVD prediction, but is still in the early stage of development as the defects of research design, report, and evaluation systems. The IVS we developed may contribute to independent external validation and the development of this field.


Assuntos
Inteligência Artificial , Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Algoritmos , África , Europa (Continente)
2.
Phys Rev Lett ; 132(13): 133603, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613308

RESUMO

An integrated quantum light source is increasingly desirable in large-scale quantum information processing. Despite recent remarkable advances, a new material platform is constantly being explored for the fully on-chip integration of quantum light generation, active and passive manipulation, and detection. Here, for the first time, we demonstrate a gallium nitride (GaN) microring based quantum light generation in the telecom C-band, which has potential toward the monolithic integration of quantum light source. In our demonstration, the GaN microring has a free spectral range of 330 GHz and a near-zero anomalous dispersion region of over 100 nm. The generation of energy-time entangled photon pair is demonstrated with a typical raw two-photon interference visibility of 95.5±6.5%, which is further configured to generate a heralded single photon with a typical heralded second-order autocorrelation g_{H}^{(2)}(0) of 0.045±0.001. Our results pave the way for developing a chip-scale quantum photonic circuit.

3.
Nicotine Tob Res ; 26(4): 474-483, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-37535700

RESUMO

INTRODUCTION: Electronic cigarettes (E-cigs) are in a controversial state. Although E-cig aerosol generally contains fewer harmful substances than smoke from burned traditional cigarettes, aerosol along with other compounds of the E-cigs may also affect lung functions and promote the development of lung-related diseases. We investigated the effects of E-cig on the pulmonary functions of male C57BL/6 mice and reveal the potential underlying mechanisms. METHODS: A total of 60 male C57BL/6 mice were randomly divided into four groups. They were exposed to fresh-air, traditional cigarette smoke, E-cig vapor with 12 mg/mL of nicotine, and E-cig with no nicotine for 8 weeks. Lung functions were evaluated by using quantitative analysis of the whole body plethysmograph, FlexiVent system, lung tissue histological and morphometric analysis, and RT-PCR analysis of mRNA expression of inflammation-related genes. In addition, the effects of nicotine and acrolein on the survival rate and DNA damage were investigated using cultured human alveolar basal epithelial cells. RESULTS: Exposure to E-cig vapor led to significant changes in lung functions and structures including the rupture of the alveolar cavity and enlarged alveolar space. The pathological changes were also accompanied by increased expression of interleukin-6 and tumor necrosis factor-α. CONCLUSIONS: The findings of the present study indicate that the safety of E-cig should be further evaluated. IMPLICATIONS: Some people currently believe that using nicotine-free E-cigs is a safe way to smoke. However, our research shows that E-cigs can cause lung damage regardless of whether they contain nicotine.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Camundongos , Animais , Masculino , Humanos , Nicotina/efeitos adversos , Nicotina/metabolismo , Camundongos Endogâmicos C57BL , Pulmão , Aerossóis/farmacologia
4.
J Nanobiotechnology ; 22(1): 52, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321555

RESUMO

Bacterial cystitis, a commonly occurring urinary tract infection (UTI), is renowned for its extensive prevalence and tendency to recur. Despite the extensive utilization of levofloxacin as a conventional therapeutic approach for bacterial cystitis, its effectiveness is impeded by adverse toxic effects, drug resistance concerns, and its influence on the gut microbiota. This study introduces Lev@PADM, a hydrogel with antibacterial properties that demonstrates efficacy in the treatment of bacterial cystitis. Lev@PADM is produced by combining levofloxacin with decellularized porcine acellular dermal matrix hydrogel and exhibits remarkable biocompatibility. Lev@PADM demonstrates excellent stability as a hydrogel at body temperature, enabling direct administration to the site of infection through intravesical injection. This localized delivery route circumvents the systemic circulation of levofloxacin, resulting in a swift and substantial elevation of the antimicrobial agent's concentration specifically at the site of infection. The in vivo experimental findings provide evidence that Lev@PADM effectively prolongs the duration of levofloxacin's action, impedes the retention and invasion of E.coli in the urinary tract, diminishes the infiltration of innate immune cells into infected tissues, and simultaneously preserves the composition of the intestinal microbiota. These results indicate that, in comparison to the exclusive administration of levofloxacin, Lev@PADM offers notable benefits in terms of preserving the integrity of the bladder epithelial barrier and suppressing the recurrence of urinary tract infections.


Assuntos
Derme Acelular , Cistite , Infecções Urinárias , Suínos , Animais , Levofloxacino , Hidrogéis
5.
BMC Anesthesiol ; 24(1): 130, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580909

RESUMO

BACKGROUND: Skin mottling is a common manifestation of peripheral tissue hypoperfusion, and its severity can be described using the skin mottling score (SMS). This study aims to evaluate the value of the SMS in detecting peripheral tissue hypoperfusion in critically ill patients following cardiac surgery. METHODS: Critically ill patients following cardiac surgery with risk factors for tissue hypoperfusion were enrolled (n = 373). Among these overall patients, we further defined a hypotension population (n = 178) and a shock population (n = 51). Hemodynamic and perfusion parameters were recorded. The primary outcome was peripheral hypoperfusion, defined as significant prolonged capillary refill time (CRT, > 3.0 s). The characteristics and hospital mortality of patients with and without skin mottling were compared. The area under receiver operating characteristic curves (AUROC) were used to assess the accuracy of SMS in detecting peripheral hypoperfusion. Besides, the relationships between SMS and conventional hemodynamic and perfusion parameters were investigated, and the factors most associated with the presence of skin mottling were identified. RESULTS: Of the 373-case overall population, 13 (3.5%) patients exhibited skin mottling, with SMS ranging from 1 to 5 (5, 1, 2, 2, and 3 cases, respectively). Patients with mottling had lower mean arterial pressure, higher vasopressor dose, less urine output (UO), higher CRT, lactate levels and hospital mortality (84.6% vs. 12.2%, p < 0.001). The occurrences of skin mottling were higher in hypotension population and shock population, reaching 5.6% and 15.7%, respectively. The AUROC for SMS to identify peripheral hypoperfusion was 0.64, 0.68, and 0.81 in the overall, hypotension, and shock populations, respectively. The optimal SMS threshold was 1, which corresponded to specificities of 98, 97 and 91 and sensitivities of 29, 38 and 67 in the three populations (overall, hypotension and shock). The correlation of UO, lactate, CRT and vasopressor dose with SMS was significant, among them, UO and CRT were identified as two major factors associated with the presence of skin mottling. CONCLUSION: In critically ill patients following cardiac surgery, SMS is a very specific yet less sensitive parameter for detecting peripheral tissue hypoperfusion.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Hipotensão , Choque Séptico , Humanos , Estado Terminal , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Hipotensão/diagnóstico , Hipotensão/complicações , Lactatos
6.
J Med Internet Res ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38869157

RESUMO

UNSTRUCTURED: In recent years, there has been an explosive development of artificial intelligence (AI), which has been widely applied in the healthcare field. As a typical AI technology, machine learning (ML) models have emerged as great potential in predicting cardiovascular diseases (CVDs) by leveraging large amounts of medical data for training and optimization, which are expected to play a crucial role in reducing the incidence and mortality rates of CVDs. Although the field has become a research hotspot, there are still many pitfalls that researchers need to pay close attention to. These pitfalls may affect the predictive performance, credibility, reliability, reproducibility of the studied models, ultimately reducing the value of the research and affecting the prospects for clinical application. Therefore, identifying and avoiding these pitfalls is a crucial task before implementing the research. However, there is currently a lack of comprehensive summary on this topic. This viewpoint aims to analyze the existing problems in terms of data quality, dataset characteristics, model design and statistical methods as well as clinic implication, and provide possible solutions to these problems, like gathering objective data, improving training, repeating measurements, increasing sample size, preventing overfitting using statistical methods, utilizing specific AI algorithms to address targeted issues, standardizing outcomes and evaluation criteria, as well as enhancing fairness and replicability, with the goal of offering reference and assistance to researchers, algorithm developers, policy makers, and clinical practitioners.

7.
Opt Lett ; 48(10): 2571-2574, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37186711

RESUMO

Two-dimensional (2D) antiferromagnetic semiconductor chromium thiophosphate (CrPS4) has gradually become a major candidate material for low-dimensional nanoelectromechanical devices due to its remarkable structural, photoelectric characteristics and potentially magnetic properties. Here, we report the experimental study of a new few-layer CrPS4 nanomechanical resonator demonstrating excellent vibration characteristics through the laser interferometry system, including the uniqueness of resonant mode, the ability to work at the very high frequency, and gate tuning. In addition, we demonstrate that the magnetic phase transition of CrPS4 strips can be effectively detected by temperature-regulated resonant frequencies, which proves the coupling between magnetic phase and mechanical vibration. We believe that our findings will promote the further research and applications of the resonator for 2D magnetic materials in the field of optical/mechanical signal sensing and precision measurement.

8.
Opt Lett ; 48(1): 81-84, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36563374

RESUMO

Bolometers based on graphene have demonstrated outstanding performance with high sensitivity and short response time. In situ adjustment of bolometers is very important in various applications, but it is still difficult to implement in many systems. Here we propose a gate-tunable bolometer based on two strongly coupled graphene nanomechanical resonators. Both resonators are exposed to the same light field, and we can measure the properties of one bolometer by directly tracking the resonance frequency shifts, and indirectly measure the other bolometer through mechanical coupling. We find that the sensitivity and the response bandwidth of both bolometers can be independently adjusted by tuning the corresponding gate voltages. Moreover, the properties of the indirectly measured bolometer show a dependence on the coupling between the two resonators, with other parameters being fixed. Our method has the potential to optimize the design of large-scale bolometer arrays, and open new horizons in infrared/terahertz astronomy and communication systems.

9.
Cell Mol Biol Lett ; 28(1): 24, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36959535

RESUMO

BACKGROUND: Sepsis is an abnormal immune response after infection, wherein the lung is the most susceptible organ to fail, leading to acute lung injury. To overcome the limitations of current therapeutic strategies and develop more specific treatment, the inflammatory process, in which T cell-derived extracellular vesicles (EVs) play a central role, should be explored deeply. METHODS: Liquid chromatography-tandem mass spectrometry was performed for serum EV protein profiling. The serum diacylglycerol kinase kappa (DGKK) and endotoxin contents of patients with sepsis-induced lung injury were measured. Apoptosis, oxidative stress, and inflammation in A549 cells, bronchoalveolar lavage fluid, and lung tissues of mice were measured by flow cytometry, biochemical analysis, enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, and western blot. RESULTS: DGKK, the key regulator of the diacylglycerol (DAG)/protein kinase C (PKC) pathway, exhibited elevated expression in serum EVs of patients with sepsis-induced lung injury and showed strong correlation with sepsis severity and disease progression. DGKK was expressed in CD4+ T cells under regulation of the NF-κB pathway and delivered by EVs to target cells, including alveolar epithelial cells. EVs produced by CD4+ T lymphocytes exerted toxic effects on A549 cells to induce apoptotic cell death, oxidative cell damage, and inflammation. In mice with sepsis induced by cecal ligation and puncture, EVs derived from CD4+ T cells also promoted tissue damage, oxidative stress, and inflammation in the lungs. These toxic effects of T cell-derived EVs were attenuated by the inhibition of PKC and NOX4, the downstream effectors of DGKK and DAG. CONCLUSIONS: This approach established the mechanism that T-cell-derived EVs carrying DGKK triggered alveolar epithelial cell apoptosis, oxidative stress, inflammation, and tissue damage in sepsis-induced lung injury through the DAG/PKC/NOX4 pathway. Thus, T-cell-derived EVs and the elevated distribution of DGKK should be further investigated to develop therapeutic strategies for sepsis-induced lung injury.


Assuntos
Lesão Pulmonar Aguda , Vesículas Extracelulares , Sepse , Animais , Camundongos , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/tratamento farmacológico , Linfócitos T CD4-Positivos , Inflamação , Estresse Oxidativo , Sepse/complicações , Linfócitos T , Diacilglicerol Quinase/metabolismo
10.
Proc Natl Acad Sci U S A ; 117(11): 5582-5587, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32123110

RESUMO

Vibrational modes in mechanical resonators provide a promising candidate to interface and manipulate classical and quantum information. The observation of coherent dynamics between distant mechanical resonators can be a key step toward scalable phonon-based applications. Here we report tunable coherent phonon dynamics with an architecture comprising three graphene mechanical resonators coupled in series, where all resonators can be manipulated by electrical signals on control gates. We demonstrate coherent Rabi oscillations between spatially separated resonators indirectly coupled via an intermediate resonator serving as a phonon cavity. The Rabi frequency fits well with the microwave burst power on the control gate. We also observe Ramsey interference, where the oscillation frequency corresponds to the indirect coupling strength between these resonators. Such coherent processes indicate that information encoded in vibrational modes can be transferred and stored between spatially separated resonators, which can open the venue of on-demand phonon-based information processing.

11.
Biochem Genet ; 61(2): 551-564, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35986828

RESUMO

SHCBP1 (Shc SH2-domain binding protein 1) is a member of the Src and collagen homolog (Shc) protein family and is closely associated with multiple signaling pathways that play important roles during hair follicle induction, morphogenesis, and cycling. The purpose of this study was to investigate SHCBP1 gene expression, polymorphisms, and the association between SHCBP1 and wool quality traits in Chinese Merino sheep. The SHCBP1 gene was shown, by qPCR, to be ubiquitously expressed in sheep tissues and differentially expressed in the adult skin of Chinese Merino and Suffolk sheep. Four SNPs (termed SHCBP1SNPs 1-4) were identified by Sanger sequencing and were located in exon 2, intron 9, intron 12, and exon 13 of the sheep SHCBP1 gene, respectively. SHCBP1SNPs 3 and 4 (rs411176240 and rs160910635) were significantly associated with wool crimp (P < 0.05). The combined polymorphism (SHCBP1SNP3-SHCBP1SNP4) was significantly associated with wool crimp (P < 0.05). Bioinformatics analysis showed that the SNPs associated with wool crimp (SHCBP1SNPs 3 and 4) might affect the pre-mRNA splicing by creating binding sites for serine-arginine-rich proteins and that SHCBP1SNP4 might alter the SHCBP1 mRNA and protein secondary structure. Our results suggest that SHCBP1 influences wool crimp and SHCBP1SNPs 3 and 4 might be useful markers for marker-assisted selection and sheep breeding.


Assuntos
Proteínas Adaptadoras da Sinalização Shc , Ovinos , , Animais , Genótipo , Fenótipo , Polimorfismo de Nucleotídeo Único , Proteínas Adaptadoras da Sinalização Shc/genética , Ovinos/genética
12.
J Am Chem Soc ; 144(22): 9559-9563, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35604644

RESUMO

Bioinspired metal-organic frameworks (MOFs) serve as suitable crystalline models for recognition and sensing of biomolecules mimicking natural processes, providing new ideas and concepts for cutting-edge biomedical applications. Here, we have successfully prepared a robust biological metal-organic framework with periodic docking grooves resembling the major and minor grooves in the DNA double helix structure, which can be used as unique recognition sites for selectively identifying l-/d-tryptophan (l-/d-Trp). Notably, successful encapsulation of Trp could be observed by single-crystal X-ray diffraction for the first time. Trp has matched size and shape to fit snugly into the major groove. Combined with isothermal titration calorimetry, it was found that ZnBTCHx could spontaneously capture l-/d-Trp through two different thermodynamic pathways: enthalpy-driven for encapsulating l-Trp and entropy-driven for uptaking d-Trp. Furthermore, molecular dynamics and density functional theory verified the role of hydrogen bonding and π-π/C-H···π interactions in the host-guest interface. This work provides unique insight for the construction of bionic models to mimic the natural binding properties, which is of great significance for the fields of pharmaceutical chemistry and biomedical science.


Assuntos
Estruturas Metalorgânicas , Triptofano , DNA/química , Ligação de Hidrogênio , Termodinâmica , Triptofano/química
13.
Rev Cardiovasc Med ; 23(3): 84, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35345251

RESUMO

BACKGROUND: Respiratory failure is one of the most common complications following cardiac surgery. Although noninvasive ventilation (NIV) has been an effective treatment, it has a high rate of intolerance. Both remifentanil and dexmedetomidine are used as sedatives in cardiac surgery (CS) patients with NIV intolerance. However, no randomized controlled trials have compared the effects of these drugs in relieving the intolerance. METHODS: REDNIVI will be a multicenter, prospective, single-blind, randomized controlled trial carried out in six clinical sites in China. Subjects with NIV intolerance will be randomized to receive remifentanil or dexmedetomidine in a ratio of 1:1. Primary outcomes of intolerance remission rate at different timings (15 minutes, 1, 3, 6, 12, 24, 36, 48, 60, 72 hours after initiation of treatment) and 72 h average remission rate will be determined. In addition, secondary outcomes such as mortality, duration of intensive care unit (ICU) stay, duration of mechanical ventilation (MV), the need for endotracheal intubation, hemodynamic changes, and delirium incidence will also be determined. CONCLUSIONS: This trial will provide evidence to determine the effects of remifentanil and dexmedetomidine in patients with NIV intolerance after cardiac surgery. CLINICAL TRIAL REGISTRATION: This study has been registered on ClinicalTrials.gov (NCT04734418).


Assuntos
Procedimentos Cirúrgicos Cardíacos , Dexmedetomidina , Ventilação não Invasiva , Remifentanil , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Dexmedetomidina/uso terapêutico , Humanos , Estudos Multicêntricos como Assunto , Ventilação não Invasiva/efeitos adversos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Remifentanil/uso terapêutico , Método Simples-Cego
14.
BMC Pulm Med ; 22(1): 304, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35941641

RESUMO

BACKGROUND: Noninvasive ventilation (NIV) has been widely used in critically ill patients after extubation. However, NIV failure is associated with poor outcomes. This study aimed to determine early predictors of NIV failure and to construct an accurate machine-learning model to identify patients at risks of NIV failure after extubation in intensive care units (ICUs). METHODS: Patients who underwent NIV after extubation in the eICU Collaborative Research Database (eICU-CRD) were included. NIV failure was defined as need for invasive ventilatory support (reintubation or tracheotomy) or death after NIV initiation. A total of 93 clinical and laboratory variables were assessed, and the recursive feature elimination algorithm was used to select key features. Hyperparameter optimization was conducted with an automated machine-learning toolkit called Neural Network Intelligence. A machine-learning model called Categorical Boosting (CatBoost) was developed and compared with nine other models. The model was then prospectively validated among patients enrolled in the Cardiac Surgical ICU of Zhongshan Hospital, Fudan University. RESULTS: Of 929 patients included in the eICU-CRD cohort, 248 (26.7%) had NIV failure. The time from extubation to NIV, age, Glasgow Coma Scale (GCS) score, heart rate, respiratory rate, mean blood pressure (MBP), saturation of pulse oxygen (SpO2), temperature, glucose, pH, pressure of oxygen in blood (PaO2), urine output, input volume, ventilation duration, and mean airway pressure were selected. After hyperparameter optimization, our model showed the greatest accuracy in predicting NIV failure (AUROC: 0.872 [95% CI 0.82-0.92]) among all predictive methods in an internal validation. In the prospective validation cohort, our model was also superior (AUROC: 0.846 [95% CI 0.80-0.89]). The sensitivity and specificity in the prediction group is 89% and 75%, while in the validation group they are 90% and 70%. MV duration and respiratory rate were the most important features. Additionally, we developed a web-based tool to help clinicians use our model. CONCLUSIONS: This study developed and prospectively validated the CatBoost model, which can be used to identify patients who are at risk of NIV failure. Thus, those patients might benefit from early triage and more intensive monitoring. TRIAL REGISTRATION: NCT03704324. Registered 1 September 2018, https://register. CLINICALTRIALS: gov .


Assuntos
Aprendizado de Máquina , Ventilação não Invasiva , Insuficiência Respiratória , Extubação , Humanos , Unidades de Terapia Intensiva , Ventilação não Invasiva/métodos , Oxigênio , Reprodutibilidade dos Testes , Respiração Artificial , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia
15.
Zhongguo Zhong Yao Za Zhi ; 47(14): 3844-3852, 2022 Jul.
Artigo em Zh | MEDLINE | ID: mdl-35850843

RESUMO

We studied the effect of Tianma Gouteng Decoction on vascular aging in spontaneously hypertensive rats(SHRs) to explore the molecular mechanism of the decoction in improving arterial vascular aging by regulating the expression of mitofusin 2(MFN2).Twenty 64-weeks-old SHRs were randomly assigned into the aging group and the treatment group(Tianma Gouteng Decoction 5.48 mg·kg~(-1)).Wistar-Kyoto(WKY) rats of 64 weeks old were taken as the normal group and SHR rats of 14 weeks old as the young group.The intervention with Tianma Gouteng Decoction lasted for 12 weeks.We then employed HE staining and Masson staining to observe the morphology of thoracic aorta under an electron microscope and measured the malondialdehyde(MDA) content, superoxide dismutase(SOD) activity, respiratory chain complex Ⅲ level, and thioredoxin peroxidase(TPX) activity.The vascular aging was detected via the biomarker senescence-associated beta-galactosidase(SA-ß-Gal).The expression levels of MFN2 and aging marker proteins silent information regulator 1(SIRT1), Klotho, p21, and p53 in thoracic aorta were detected by immunohistochemistry/fluorescence, qRT-PCR, and Western blot.Compared with the young group and the normal group, the aging group had risen blood pressure, lumen stenosis caused by thickened intima of blood vessels, decreased SOD and TPX activities, increased MDA and mitochondrial respiratory chain complex Ⅲ levels, down-regulated expression of MFN2, SIRT1, and Klotho, and up-regulated expression of p21 and p53(P<0.01 or P<0.05).The treatment with Tianma Gouteng Decoction significantly lowered blood pressure, mitigated vascular intimal thickening, increased SOD and TPX activities, and decreased MDA and mitochondrial respiratory chain complex Ⅲ levels, thus alleviating vascular aging.At the same time, the decoction up-regulated the expression of MFN2, SIRT1, and Klotho, while down-regulated that of p21 and p53(P<0.01 or P<0.05).In summary, Tianma Gouteng Decoction can significantly delay the vascular aging in hypertension.Specifically, it may up-regulate the expression of MFN2 and regulate the expression of aging-related proteins to alleviate oxidative stress.


Assuntos
Hipertensão , Sirtuína 1 , Envelhecimento/genética , Animais , Medicamentos de Ervas Chinesas , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Hipertensão/tratamento farmacológico , Hipertensão/genética , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Sirtuína 1/metabolismo , Superóxido Dismutase/metabolismo , Proteína Supressora de Tumor p53
16.
Opt Express ; 29(1): 256-271, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33362119

RESUMO

We theoretically investigate the preparation of mid-infrared (MIR) spectrally-uncorrelated biphotons from a spontaneous parametric down-conversion process using doped LN crystals, including MgO doped LN, ZnO doped LN, and In2O3 doped ZnLN with doping ratio from 0 to 7 mol%. The tilt angle of the phase-matching function and the corresponding poling period are calculated under type-II, type-I, and type-0 phase-matching conditions. We also calculate the thermal properties of the doped LN crystals and their performance in Hong-Ou-Mandel interference. It is found that the doping ratio has a substantial impact on the group-velocity-matching (GVM) wavelengths. Especially, the GVM2 wavelength of co-doped InZnLN crystal has a tunable range of 678.7 nm, which is much broader than the tunable range of less than 100 nm achieved by the conventional method of adjusting the temperature. It can be concluded that the doping ratio can be utilized as a degree of freedom to manipulate the biphoton state. The spectrally uncorrelated biphotons can be used to prepare pure single-photon source and entangled photon source, which may have promising applications for quantum-enhanced sensing, imaging, and communications at the MIR range.

17.
Opt Express ; 29(11): 16241-16248, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34154191

RESUMO

Graphene has been considered as one of the best materials to implement mechanical resonators due to their excellent properties such as low mass, high quality factors and tunable resonant frequencies. Here we report the observation of phonon lasing induced by the photonthermal pressure in a few-layer graphene resonator at room temperature, where the graphene resonator and the silicon substrate form an optical cavity. A marked threshold in the oscillation amplitude and a narrowing linewidth of the vibration mode are observed, which confirms a phonon lasing process in the graphene resonator. Our findings will stimulate the studies on phononic phenomena, help to establish new functional devices based on graphene mechanical resonators, and might find potential applications in classical and quantum sensing fields, as well as in information processing.

18.
Nitric Oxide ; 109-110: 26-32, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33667622

RESUMO

BACKGROUND: To assess the relationship between the intrapulmonary shunt and PaO2/FiO2 in severe hypoxemic patients after acute type A aortic dissection (ATAAD) surgery and to evaluate the effect of inhaled nitric oxide (iNO) on intrapulmonary shunt. METHODS: Postoperative ATAAD patients with PaO2/FiO2 ≤ 150 mmHg were enrolled. Intrapulmonary shunt was calculated from oxygen content of different sites (artery [CaO2], mixed venous [CvO2], and alveolar capillary [CcO2]) using the Fick equation, where intrapulmonary shunt = (CcO2-CaO2)/(CcO2-CvO2). Related variables were measured at baseline (positive end expiratory pressure [PEEP] 5 cm H2O), 30 min after increasing PEEP (PEEP 10 cm H2O), 30 min after 5 ppm iNO therapy (PEEP 10 cm H2O + iNO), and 30 min after decreasing PEEP (PEEP 5 cm H2O + iNO). RESULTS: A total of 20 patients were enrolled between April 2019 and December 2019. Intrapulmonary shunt and PaO2/FiO2 were correlated in severe hypoxemic, postoperative ATAAD patients (adjusted R2 = 0.467, p < 0.001). A mixed model for repeated measures revealed that iNO, rather than increasing PEEP, significantly decreased the intrapulmonary shunt (by 15% at a PEEP of 5 cm H2O and 16% at a PEEP of 10 cm H2O, p < 0.001 each) and increased PaO2/FiO2 (by 63% at a PEEP of 5 cm H2O and 65% at a PEEP of 10 cm H2O, p < 0.001 each). After iNO therapy, the decrement of intrapulmonary shunt and the increment of PaO2/FiO2 were also correlated (adjusted R2 = 0.375, p < 0.001). CONCLUSIONS: This study showed that intrapulmonary shunt and PaO2/FiO2 were correlated in severe hypoxemic, postoperative ATAAD patients. Furthermore, iNO, rather than increasing PEEP, significantly decreased the intrapulmonary shunt to improve severe hypoxemic conditions.


Assuntos
Dissecção Aórtica/complicações , Hipóxia/tratamento farmacológico , Óxido Nítrico/uso terapêutico , Troca Gasosa Pulmonar/efeitos dos fármacos , Administração por Inalação , Adulto , Aorta/cirurgia , Gasometria , Humanos , Hipóxia/etiologia , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/administração & dosagem , Oxigênio/metabolismo , Respiração com Pressão Positiva
19.
Br J Clin Pharmacol ; 87(8): 3292-3300, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33506975

RESUMO

AIMS: This open-label, phase I study evaluated the pharmacokinetics and safety of pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) for the treatment of chemotherapy-induced neutropenia in children with acute leukaemia. METHODS: PEG-rhG-CSF was administered as a single 100 mcg/kg (3 mg maximum dose) subcutaneous injection at the end of each chemotherapy period when neutropenia occurred. Blood samples were obtained from patients treated with PEG-rhG-CSF. PEG-rhG-CSF serum concentrations were determined by an enzyme-linked immunosorbent assay. Population pharmacokinetic (PPK) analysis was implemented using the nonlinear mixed-effects model. Short-term safety was evaluated through adverse events collection (registered at clinicaltrials.gov identifier: 03844360). RESULTS: A total of 16 acute leukaemia patients (1.8-13.6 years) were included, of whom two (12.5%) had grade 3 neutropenia, six (37.5%) had grade 4 neutropenia, and eight (50.0%) had severe neutropenia. For PPK modelling, 64 PEG-rhG-CSF serum concentrations were obtainable. A one-compartment model with first-order elimination was used for pharmacokinetic data modelling. The current weight was a significant covariate. The median (range) of clearance (CL) and area under the serum concentration-time curve (AUC) were 5.65 (1.49-14.45) mL/h/kg and 16514.75 (6632.45-54423.30) ng·h/mL, respectively. Bone pain, pyrexia, anaphylaxis and nephrotoxicity were not observed. One patient died 13 days after administration, and the objective assessment of causality was that an association with PEG-rhG-CSF was "possible". CONCLUSIONS: The AUC of PEG-rhG-CSF (100 mcg/kg, 3 mg maximum dose) in paediatric patients with acute leukaemia were similar to those of PEG-rhG-CSF (100 mcg/kg) in children with sarcoma. PEG-rhG-CSF is safe, representing an important therapeutic option for chemotherapy-induced neutropenia in paediatric patients with acute leukaemia.


Assuntos
Leucemia Mieloide Aguda , Neutropenia , Criança , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Neutropenia/induzido quimicamente , Polietilenoglicóis/efeitos adversos , Proteínas Recombinantes
20.
Arch Insect Biochem Physiol ; 108(2): e21837, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34293199

RESUMO

The olfactory system must detect and discriminate various semiochemicals in the environment. In response to such diversity, insects have evolved a family of odorant-gated ion channels composed of a common receptor (coreceptor, Orco) and a ligand-binding tuning odorant receptor (OR) that confers odour specificity. This study aims to examine the expression pattern of Orco gene of Grapholita molesta (GmolOrco) and to elucidate the role of GmolOrco in detecting G. molesta sex pheromone and green leaf volatiles by using gene silencing via RNA interference (RNAi) coupled antennal electrophysiological (EAG). Multiple sequence alignment showed that GmolOrco shared high sequence similarities with the Orco ortholog of lepidopterans. The results of real-time quantitative PCR detection demonstrated that GmolOrco was predominantly expressed in adult antennae and had the highest expression quantity in adult period among the different developmental stages. Compared with the noninjected controls, GmolOrco expression in GmolOrcodouble-stranded RNA (dsRNA)-injected males was reduced to 39.92% and that in females was reduced to 40.43%. EAG assays showed that the responses of GmolOrco-dsRNA injected males to sex pheromones (Z)-8-dodecenyl acetate (Z8-12:OAc) and (Z)-8-dodecenyl alcohol (Z8-12:OH) were significantly reduced, and the GmolOrco-dsRNA-injected female to green leaf volatile (Z)-3-hexenyl acetate also significantly declined. We inferred that Orco-mediated olfaction was different in male and female G. molesta adults and was mainly involved in recognizing the sex pheromones released by female moths.


Assuntos
Mariposas , Receptores Odorantes , Animais , Antenas de Artrópodes/metabolismo , Feminino , Expressão Gênica , Genes de Insetos , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Masculino , Mariposas/genética , Mariposas/metabolismo , Mariposas/fisiologia , Odorantes , Plantas/metabolismo , Interferência de RNA , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Atrativos Sexuais/metabolismo , Caracteres Sexuais , Compostos Orgânicos Voláteis/metabolismo
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