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1.
Cell Biol Int ; 48(4): 389-403, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38317355

RESUMO

Degeneration of intervertebral discs is considered one of the most important causes of low back pain and disability. The intervertebral disc (IVD) is characterized by its susceptibility to various stressors that accelerate the senescence and apoptosis of nucleus pulposus cells, resulting in the loss of these cells and dysfunction of the intervertebral disc. Therefore, how to reduce the loss of nucleus pulposus cells under stress environment is the main problem in treating intervertebral disc degeneration. Autophagy is a kind of programmed cell death, which can provide energy by recycling substances in cells. It is considered to be an effective method to reduce the senescence and apoptosis of nucleus pulposus cells under stress. However, further research is needed on the mechanisms by which autophagy of nucleus pulposus cells is regulated under stress environments. M6A methylation, as the most extensive RNA modification in eukaryotic cells, participates in various cellular biological functions and is believed to be related to the regulation of autophagy under stress environments, may play a significant role in nucleus pulposus responding to stress. This article first summarizes the effects of various stressors on the death and autophagy of nucleus pulposus cells. Then, it summarizes the regulatory mechanism of m6A methylation on autophagy-related genes under stress and the role of these autophagy genes in nucleus pulposus cells. Finally, it proposes that the methylation modification of autophagy-related genes regulated by m6A may become a new treatment approach for intervertebral disc degeneration, providing new insights and ideas for the clinical treatment of intervertebral disc degeneration.


Assuntos
Adenina/análogos & derivados , Degeneração do Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Humanos , Degeneração do Disco Intervertebral/metabolismo , Disco Intervertebral/metabolismo , Núcleo Pulposo/metabolismo , Autofagia , Apoptose , Metilação
2.
Curr Pain Headache Rep ; 28(3): 95-108, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37976014

RESUMO

PURPOSE OF REVIEW: Intervertebral disc degeneration is the primary etiology of low back pain and radicular pain. This review examines the roles of crucial chemokines in different stages of degenerative disc disease, along with interventions targeting chemokine function to mitigate disc degeneration. RECENT FINDINGS: The release of chemokines from degenerated discs facilitates the infiltration and activation of immune cells, thereby intensifying the inflammatory cascade response. The migration of immune cells into the venous lumen is concomitant with the emergence of microvascular tissue and nerve fibers. Furthermore, the presence of neurogenic factors secreted by disc cells and immune cells stimulates the activation of pain-related cation channels in the dorsal root ganglion, potentially exacerbating discogenic and neurogenic pain and intensifying the degenerative cascade response mediated by chemokines. Gaining a deeper comprehension of the functions of chemokines and immune cells in these processes involving catabolism, angiogenesis, and injury detection could offer novel therapeutic avenues for managing symptomatic disc disease.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Dor Lombar , Humanos , Degeneração do Disco Intervertebral/terapia , Disco Intervertebral/metabolismo , Dor Lombar/etiologia , Quimiocinas/metabolismo , Gânglios Espinais
3.
Eur Spine J ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509262

RESUMO

AIMS: This research aims to construct and verify an accurate nomogram for forecasting the 3-, 5-, and 7-year outcomes in pediatric patients afflicted with spinal cord injury (SCI). METHODS: Pediatric patients with SCI from multiple hospitals in China, diagnosed between Jan 2005 and Jan 2020, were incorporated into this research. Half of these patients were arbitrarily chosen for training sets, and the other half were designated for external validation sets. The Cox hazard model was employed to pinpoint potential prognosis determinants related to the American Spinal Injury Association (ASIA) and Functional Independence Assessment (FIM) index. These determinants were then employed to formulate the prognostic nomogram. Subsequently, the bootstrap technique was applied to validate the derived model internally. RESULTS: In total, 224 children with SCI were considered for the final evaluation, having a median monitoring duration of 68.0 months. The predictive nomogram showcased superior differentiation capabilities, yielding a refined C-index of 0.924 (95% CI: 0.883-0.965) for the training cohort and a C-index of 0.863 (95% CI: 0.735-0.933) for the external verification group. Additionally, when applying the aforementioned model to prognostic predictions as classified by the FIM, it demonstrated a high predictive value with a C-index of 0.908 (95% CI: 0.863-0.953). Moreover, the calibration diagrams indicated a consistent match between the projected and genuine ASIA outcomes across both sets. CONCLUSION: The crafted and verified prognostic nomogram emerges as a dependable instrument to foresee the 3-, 5-, and 7-year ASIA and FIM outcomes for children suffering from SCI.

4.
Spinal Cord ; 62(4): 183-191, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38409493

RESUMO

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: Hospital-acquired infections (HAIs) pose a significant risk for pediatric patients with spinal cord injuries (SCIs), potentially leading to extended hospital stays and increased morbidity. This study aims to identify patients at higher risk for HAIs. SETTING: Hospitals from multiple areas in China. METHODS: This retrospective study included 220 pediatric SCI patients from Jan 2005 to Dec 2023, divided into a training set (n = 154) and a validation set (n = 66). We conducted a multivariate logistic regression analysis to identify risk factors associated with HAIs and constructed a predictive nomogram. The model's performance was assessed using receiver operating characteristic (ROC) curves, area under the ROC curve (AUC) and calibration plots, while decision curve analysis was utilized to determine clinical utility. RESULTS: The nomogram incorporated age, time from injury to the hospital, history of urinary and pulmonary infections, urobilinogen positivity, damaged segments, and admission American Spinal Injury Association (ASIA) scores. The model demonstrated excellent discrimination in the training set (AUC = 0.957) and good discrimination in the validation set (AUC = 0.919). Calibration plots indicated an acceptable fit between predicted probabilities and observed outcomes. Decision curve analysis confirmed the model's net benefit over clinical decision thresholds in both sets. CONCLUSION: We developed and validated a predictive nomogram for HAIs in pediatric SCI patients that shows promise for clinical application. The model can assist healthcare providers in identifying patients at higher risk for HAIs, potentially facilitating early interventions and improved patient care strategies.


Assuntos
Traumatismos da Medula Espinal , Humanos , Criança , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/epidemiologia , Estudos Retrospectivos , Nomogramas , Hospitais , Fatores de Risco
5.
Am J Physiol Cell Physiol ; 325(5): C1212-C1227, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721001

RESUMO

Ferroptosis has been proven critical for survival following bone marrow mesenchymal stem cells (BMSCs) explantation. Suppression of ferroptosis in BMSCs will be a valid tactic to elevate the therapeutic potential of engrafted BMSCs. Prominin2 is a pentaspanin protein involved in mediating iron efflux and thus modulates resistance to ferroptosis, but its role in tert-butyl hydroperoxide (TBHP)-induced BMSCs ferroptosis remains elusive. We examined the biological effect of prominin2 in vitro and in vivo by using cell proliferation assay, iron assay, reactive oxygen species (ROS) examination, malondialdehyde assay, glutathione (GSH) examination, Western blot, quantitative reverse transcription-PCR, immunofluorescence staining assay, gene expression inhibition and activation, co-immunoprecipitation (CO-IP) assay, radiographic analysis, and histopathological analysis. Our study demonstrated that prominin2 activity was impaired in TBHP-induced BMSCs ferroptosis. We found that PROM2 (encoding the protein prominin2) activation delayed the onset of ferroptosis and PROM2 knockdown deteriorated the course of ferroptosis. CO-IP, Western blot, and immunofluorescence demonstrated that prominin2 exerts antiferroptosis effects by inhibiting BTB and CNC homology 1 (BACH1) that promotes ROS generation, and thus exerts potent antioxidant effects in oxidative stress (OS)-induced BMSCs ferroptosis, including elevating BMSCs' survival rate and enhancing GSH contents. BMSCs with PROM2 overexpression also partially delayed the progression of intervertebral disk degeneration in vivo, as illustrated by less loss of disk height and lower histological scores. Our findings revealed a mechanism that the prominin2/BACH1/ROS axis participates in BMSCs ferroptosis and the strengthening of this axis is promising to maintain BMSCs' survival after explantation.NEW & NOTEWORTHY We found that prominin2 might be a potential biomarker and is expected to be utilized to augment engrafted bone marrow mesenchymal stem cells (BMSCs) survival rate. The prominin2/BTB and CNC homology 1 (BACH1)/reactive oxygen species (ROS) axis, which participates in the regulation of BMSCs ferroptosis induced by tert-butyl hydroperoxide (TBHP), is uncovered in our study. The therapeutic targeting of the prominin2/BACH1/ROS axis components is promising to elevate the survival of transplanted BMSCs in clinical practice.

6.
Glob Chang Biol ; 29(24): 6856-6866, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37855153

RESUMO

Marine primary producers are largely dependent on and shape the Earth's climate, although their relationship with climate varies over space and time. The growth of phytoplankton and associated marine primary productivity in most of the modern global ocean is limited by the supply of nutrients, including the micronutrient iron. The addition of iron via episodic and frequent events drives the biological carbon pump and promotes the sequestration of atmospheric carbon dioxide (CO2 ) into the ocean. However, the dependence between iron and marine primary producers adaptively changes over different geological periods due to the variation in global climate and environment. In this review, we examined the role and importance of iron in modulating marine primary production during some specific geological periods, that is, the Great Oxidation Event (GOE) during the Huronian glaciation, the Snowball Earth Event during the Cryogenian, the glacial-interglacial cycles during the Pleistocene, and the period from the last glacial maximum to the late Holocene. Only the change trend of iron bioavailability and climate in the glacial-interglacial cycles is consistent with the Iron Hypothesis. During the GOE and the Snowball Earth periods, although the bioavailability of iron in the ocean and the climate changed dramatically, the changing trend of many factors contradicted the Iron Hypothesis. By detangling the relationship among marine primary productivity, iron availability and oceanic environments in different geological periods, this review can offer some new insights for evaluating the impact of ocean iron fertilization on removing CO2 from the atmosphere and regulating the climate.


Assuntos
Ferro , Água do Mar , Ferro/análise , Dióxido de Carbono/análise , Oceanos e Mares , Atmosfera , Fertilização
7.
Methods ; 205: 53-62, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35569734

RESUMO

Cough event detection is the foundation of any measurement associated with cough, one of the primary symptoms of pulmonary illnesses. This paper proposes HearCough, which enables continuous cough event detection on edge computing hearables, by leveraging always-on active noise cancellation (ANC) microphones in commodity hearables. Specifically, we proposed a lightweight end-to-end neural network model - Tiny-COUNET and its transfer learning based traning method. When evaluated on our acted cough event dataset, Tiny-COUNET achieved equivalent detection performance but required significantly less computational resources and storage space than cutting-edge cough event detection methods. Then we implemented HearCough by quantifying and deploying the pre-trained Tiny-COUNET to a popular micro-controller in consumer hearables. Lastly, we evaluated that HearCough is effective and reliable for continuous cough event detection through a field study with 8 patients. HearCough achieved 2 Hz cough event detection with an accuracy of 90.0% and an F1-score of 89.5% by consuming an additional 5.2 mW power. We envision HearCough as a low-cost add-on for future hearables to enable continuous cough detection and pulmonary health monitoring.


Assuntos
Tosse , Redes Neurais de Computação , Tosse/diagnóstico , Humanos
8.
Biochem Genet ; 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38104050

RESUMO

Approximately 80% of individuals encounter lower back pain (LBP), a prevalent clinical issue largely attributed to intervertebral disc degeneration (IDD). Ferroptosis is an iron-dependent lipid peroxidation-driven cell death, and there is growing evidence that ferroptosis plays an important role in various human diseases. However, the underlying mechanism of ferroptosis in IDD remains unclear. This study aims to reveal the potential hub genes and related pathways of ferroptosis in the pathogenesis and progression of IDD. In this study, we analyzed three microarray datasets from the GEO database. Additionally, we downloaded ferroptosis-related genes from FerrDb-V2 and extracted apoptosis-related genes from UniProt as a control to show the specificity of ferroptosis. Weighted gene co-expression network analysis (WGCNA) was performed to identify the IDD-related module genes. Then, ferroptosis-related genes and apoptosis-related genes were separately overlapped with the IDD-related module genes, resulting in the identification of 35 ferroptosis-related module genes (FRMG) and 142 apoptosis-related module genes (ARMG). Furthermore, we performed functional enrichment analysis and protein-protein interaction network, and Cytoscape along with CytoHubba was used to identify the hub genes. Finally, logistic regression models were constructed and identified two hub FRMGs (PTEN and EGFR) and one hub ARMG (CTNNB1), which could distinguish IDD patients from controls (P < 0.05). The areas under the ROC curves were 0.792 and 0.730, respectively, suggesting that ferroptosis is more specific than apoptosis in IDD. In conclusion, this study provided fresh perspectives on ferroptosis in the pathogenesis and progression of IDD that can be used to evaluate potential biomarker genes and therapeutic targets.

9.
J Sci Food Agric ; 103(11): 5261-5269, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37005375

RESUMO

BACKGROUND: The high viscosity of konjac glumannan (KGM) limits its application in meat processing. In this work, the effects of konjac oligo-glucomannan (KOG), as a derivative of KGM, on the emulsifying properties of myofibrillar protein (MP) and the related mechanism were investigated. RESULTS: It was found that the addition of KOG had no significant effect on the secondary structure of MP, but altered the tertiary conformation of MP, resulting in exposure of tyrosine residues to polar microenvironments and decreased intrinsic fluorescence intensity. In addition, the addition of KOG increased the emulsifying activity of MP, resulting in decreased particle size and improved physical stability of the emulsion. The emulsifying activity of MP reached the maximum value when 1.0 wt% KOG was added. Moreover, the interfacial tension and interfacially adsorbed protein content of MP/KOG emulsions decreased with the increase in KOG concentration. CONCLUSION: These findings demonstrated that KOG mainly interacted with MP and changed the amphipathy of the KOG-MP at the oil-water interface, forming a stable interface film to improve the emulsifying properties of MP. © 2023 Society of Chemical Industry.


Assuntos
Amorphophallus , Amorphophallus/química , Proteínas/química , Reologia/métodos , Emulsões/química , Viscosidade
10.
Environ Geochem Health ; 45(3): 881-897, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35348989

RESUMO

Evaluating heavy metal pollution level in the soils and apportioning the source-specific health risk of heavy metals are critical for proposing environmental protection and remediation strategies to protection human health. This study explored heavy metal pollution and associated source-specific health risks in a typical rural industrial area, southwestern China. A total of 105 topsoil samples were collected and the concentrations of heavy metals, including As, Cd, Cr, Cu, Ni, Pb and Zn, were determined. Pollution load index and enrichment factors were used to evaluate the pollution level of heavy metals. Positive matrix factorization (PMF) model was applied to apportion the heavy metals and the associated source-specific health risks to adults and children were estimated via combining the PMF model with the health risk assessment. The results indicated that the soils were highly polluted by multiple heavy metals, especially for Cd, with the EF values of 24.94 and 22.55 in the upstream and downstream areas, respectively. Source apportionment results showed that atmospheric deposition, smelting activities, fertilizer and sewage application, and agrochemical utilization were the main anthropogenic sources, with the contributions of 37.11%, 23.69%, 19.69%, and 19.51%, respectively. Source-specific risk assessment identified atmospheric deposition as the priority source for the non-carcinogenic (NCR) and carcinogenic risks (CR) in the study area, with the contribution of 43.71% and 52.52% for adults, and 44.29% and 52.58% for children, respectively. Moreover, non-carcinogenic and carcinogenic risks posed to children (NCR: 2.84; CR: 1.31 × 10-4) from four sources was higher than those posed to adults (NCR: 0.29; CR: 5.86 × 10-5). The results of source-specific health risk assessment provided the valuable information on the priority sources for pollution preventing and risk controlling.


Assuntos
Metais Pesados , Poluentes do Solo , Adulto , Criança , Humanos , Solo , Monitoramento Ambiental , Cádmio/análise , Incerteza , Poluentes do Solo/análise , Metais Pesados/toxicidade , Metais Pesados/análise
11.
Int Wound J ; 20(4): 981-994, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36200336

RESUMO

Surgical site infection (SSI) is a common and serious complication of transforaminal lumbar interbody fusion (TLIF), and the occurrence of SSI usually leads to prolonged hospitalisation, increased medical costs, poor prognosis, and even death. The objectives of this study were to compare the incidence of SSI in patients with type 2 diabetes, investigate the correlation between perioperative glycemic variability and postoperative SSI, and develop a nomogram model to predict the risk of SSI. This study retrospectively analysed 339 patients with type 2 diabetes who underwent TLIF in the spinal surgery department of the Affiliated Zhongda Hospital of Southeast University from January 2018 to September 2021. The medical records of all patients were collected, and postoperative infection cases were determined according to the diagnostic criteria of surgical site infection. The risk factors for postoperative SSI were analysed by univariate and multivariate logistic regression. And Nomogram prediction model was established and validated. The nomogram incorporated seven independent predictors. Preoperative FPG-CV was the most important independent risk predictor of SSI, followed by preoperative MFBG, duration of drain placement, postoperative FPG-CV, preoperative blood glucose control scheme, duration of diabetes >5 years, and the number of fused vertebrae ≥2. The nomogram showed good diagnostic accuracy for the SS of both the training cohort and the validation cohort (AUC = 0.915 and AUC = 0.890). The calibration curves for the two cohorts both showed optimal agreement between nomogram prediction and actual observation. In conclusion, preoperative and postoperative glycemic variability is closely related to the occurrence of SSI. We developed and validated a nomogram to accurately predict the risk of SSI after TLIF surgery. It's helpful for spinal surgeons to formulate reasonable treatment plans and prevention strategies for type 2 diabetes patients.


Assuntos
Diabetes Mellitus Tipo 2 , Fusão Vertebral , Humanos , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Diabetes Mellitus Tipo 2/complicações , Estudos Retrospectivos , Nomogramas , Vértebras Lombares/cirurgia , Fusão Vertebral/efeitos adversos
12.
Opt Express ; 30(21): 37619-37636, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36258347

RESUMO

In interferometer measurements, the inconsistency of the optical range through which the reference and test lights pass introduces a retrace error in the phase measurement. In this study, we propose an iterative retrace error correction method in interferometry. A black-box model is established based on the linear and squared relationships between the retrace error and the tilt of the testing surface. The error correction phase is obtained using the least-squares method; thereafter, the global tilt is determined to iteratively correct the retrace error. The root mean square (RMS) of the residuals was > 3.2 × 10-5λ, >6.4 × 10-3λ, and >1.4 × 10-3λ in the simulation, experimentally computed retrace error correction in the planar measurement, and spherical measurement, respectively, proving that the retrace error can be effectively corrected.

13.
Neurosurg Focus ; 52(4): E7, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35364584

RESUMO

OBJECTIVE: The purpose of this study was to develop natural language processing (NLP)-based machine learning algorithms to automatically differentiate lumbar disc herniation (LDH) and lumbar spinal stenosis (LSS) based on positive symptoms in free-text admission notes. The secondary purpose was to compare the performance of the deep learning algorithm with the ensemble model on the current task. METHODS: In total, 1921 patients whose principal diagnosis was LDH or LSS between June 2013 and June 2020 at Zhongda Hospital, affiliated with Southeast University, were retrospectively analyzed. The data set was randomly divided into a training set and testing set at a 7:3 ratio. Long Short-Term Memory (LSTM) and extreme gradient boosting (XGBoost) models were developed in this study. NLP algorithms were assessed on the testing set by the following metrics: receiver operating characteristic (ROC) curve, area under the curve (AUC), accuracy score, recall score, F1 score, and precision score. RESULTS: In the testing set, the LSTM model achieved an AUC of 0.8487, accuracy score of 0.7818, recall score of 0.9045, F1 score of 0.8108, and precision score of 0.7347. In comparison, the XGBoost model achieved an AUC of 0.7565, accuracy score of 0.6961, recall score of 0.7387, F1 score of 0.7153, and precision score of 0.6934. CONCLUSIONS: NLP-based machine learning algorithms were a promising auxiliary to the electronic health record in spine disease diagnosis. LSTM, the deep learning model, showed better capacity compared with the widely used ensemble model, XGBoost, in differentiation of LDH and LSS using positive symptoms. This study presents a proof of concept for the application of NLP in prediagnosis of spine disease.


Assuntos
Deslocamento do Disco Intervertebral , Estenose Espinal , Humanos , Deslocamento do Disco Intervertebral/diagnóstico , Aprendizado de Máquina , Processamento de Linguagem Natural , Estudos Retrospectivos , Estenose Espinal/diagnóstico
14.
Br J Neurosurg ; 36(4): 427-435, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33377806

RESUMO

OBJECTIVE: The aim of this study was to determine whether obesity affects the operation, complications and outcomes after open posterior lumbar spinal fusion surgery for the treatment of low back pain and leg pain. METHODS: A meta-analysis of studies that compared the outcome of posterior lumbar spinal fusion in obese and non-obese patients. A total of 16 studies were included. RESULTS: There was no difference in pain and functional outcomes. Posterior lumbar spinal fusion in obese patients resulted in a statistically significant increase in intra-operative blood loss (weighted mean difference 40.93, 95% confidence interval (CI) 15.97-65.90, n = 243, and p=.001), longer duration of surgery (weighted mean difference -1.64, 95% CI -4.12 to 0.84, n = 1460, and p=.19), more complications (odds ratio: 1.59, 95% CI 1.24-2.05, n = 339, and p<.001) and extend length of stay (weighted mean difference 0.31, 95% CI 0.07-0.55, n = 1408, and p=.01). CONCLUSIONS: Obese patients experience more blood loss, longer duration of surgery, more complications and extended length of stay, but their back and leg pain and functional outcomes are similar to non-obese patients. Based on these results, obesity is not a contraindication to open posterior lumbar spinal fusion surgery.


Assuntos
Dor Lombar , Fusão Vertebral , Humanos , Dor Lombar/etiologia , Dor Lombar/cirurgia , Vértebras Lombares/cirurgia , Obesidade/complicações , Obesidade/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos , Resultado do Tratamento
15.
Sensors (Basel) ; 23(1)2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36616633

RESUMO

Voice communication using an air-conduction microphone in noisy environments suffers from the degradation of speech audibility. Bone-conduction microphones (BCM) are robust against ambient noises but suffer from limited effective bandwidth due to their sensing mechanism. Although existing audio super-resolution algorithms can recover the high-frequency loss to achieve high-fidelity audio, they require considerably more computational resources than is available in low-power hearable devices. This paper proposes the first-ever real-time on-chip speech audio super-resolution system for BCM. To accomplish this, we built and compared a series of lightweight audio super-resolution deep-learning models. Among all these models, ATS-UNet was the most cost-efficient because the proposed novel Audio Temporal Shift Module (ATSM) reduces the network's dimensionality while maintaining sufficient temporal features from speech audio. Then, we quantized and deployed the ATS-UNet to low-end ARM micro-controller units for a real-time embedded prototype. The evaluation results show that our system achieved real-time inference speed on Cortex-M7 and higher quality compared with the baseline audio super-resolution method. Finally, we conducted a user study with ten experts and ten amateur listeners to evaluate our method's effectiveness to human ears. Both groups perceived a significantly higher speech quality with our method when compared to the solutions with the original BCM or air-conduction microphone with cutting-edge noise-reduction algorithms.


Assuntos
Percepção da Fala , Humanos , Ruído , Condução Óssea , Comunicação , Fala
16.
Aquac Nutr ; 2022: 4355182, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36860430

RESUMO

A 30-day feeding trial was designed to investigate the physical properties of chitosan-coated microdiet (CCD) and the effect of CCD on survival, growth performance, activities of digestive enzymes, intestinal development, antioxidant capacity, and inflammatory response of large yellow croaker larvae (initial weight: 3.81 ± 0.20 mg). Four isonitrogenous (50% crude protein) and isolipidic (20% crude lipid) microdiets were prepared with different concentrations of chitosan wall material by spray drying method (0.00%, 0.30%, 0.60%, and 0.90%, weight (chitosan) : volume (acetic acid)). Results showed that the lipid encapsulation efficiency (control: 60.52%, Diet1: 84.63%, Diet2: 88.06%, Diet3: 88.65%) and nitrogen retention efficiency (control: 63.76%, Diet1: 76.14%, Diet2: 79.52%, Diet3: 84.68%) correlated positively with the concentration of wall material (P < 0.05). Furthermore, the loss rate of CCD was significantly lower than the uncoated diet. Larvae fed the diet with 0.60% CCD had significantly higher specific growth rate (13.52 and 9.95%/day) and survival rate (14.73 and 12.58%) compared to the control group (P < 0.05). Larvae fed the diet with 0.30% CCD had significantly higher trypsin activity in pancreatic segments than the control group (4.47 and 3.05 U/mg protein) (P < 0.05). Larvae fed the diet with 0.60% CCD had significantly higher activity of leucine aminopeptidase (7.29 and 4.77 mU/mg protein) and alkaline phosphatase (83.37 and 46.09 U/mg protein) in the brush border membrane than those of the control group (P < 0.05). The intestinal epithelial proliferation- and differentiation-related factors (zo-1, zo-2, and pcna) in larvae fed the diet with 0.30% CCD had higher expression than those of the control group (P < 0.05). When the concentration of wall material reached 0.90%, the larvae had significantly higher superoxide dismutase activity than that of the control group (27.27 and 13.72 U/mg protein) (P < 0.05). Meanwhile, malondialdehyde contents were significantly lower in larvae fed the diet with 0.90% CCD than that of the control group (8.79 and 6.79 nmol/mg protein) (P < 0.05). 0.30%~0.60% CCD significantly increased the activity of total nitric oxide synthase (2.31, 2.60, and 2.05 mU/mg protein) and inducible nitric oxide synthase (1.91, 2.01, and 1.63 mU/mg protein) and had significantly higher transcriptional levels of inflammatory factor genes (il-1ß, tnf-α, and il-6) than those of the control group (P < 0.05). The results indicated chitosan-coated microdiet had great potential in feeding large yellow croaker larvae in addition to reducing nutrition loss.

17.
Aquac Nutr ; 2022: 5508120, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36860459

RESUMO

A 30-day feeding trial was conducted to determine the effects of dietary glycyrrhizin (GL) on survival, growth performance, expression of feeding-related genes, activities of digestive enzymes, antioxidant capacity, and expression of inflammatory factors of large yellow croaker larvae with an initial weight of 3.78 ± 0.27 mg. Four 53.80% crude protein and 16.40% crude lipid diets were formulated with supplementation of 0%, 0.005%, 0.01%, and 0.02% GL, respectively. Results indicated that larvae fed diets with GL had higher survival rate and specific growth rate than the control (P < 0.05). Compared with the control, the mRNA expression of orexigenic factor genes including neuropeptide Y (npy) and agouti-related protein (agrp) were significantly increased in larvae fed the diet with 0.005% GL, while the mRNA expression of anorexigenic factor genes including thyrotropin-releasing hormone (trh), cocaine and amphetamine regulated transcript (cart), and leptin receptor (lepr) were significantly decreased in larvae fed the diet with 0.005% GL (P < 0.05). The trypsin activity in larvae fed the diet with 0.005% GL was significantly higher than the control (P < 0.05). The alkaline phosphatase (AKP) activity in larvae fed the diet with 0.01% GL was significantly higher than the control (P < 0.05). A clear increase of total glutathione (T-GSH) content, activities of superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) was observed in larvae fed the diet with 0.01% GL compared with the control (P < 0.05). Moreover, the mRNA expression of interleukin-1ß (il-1ß) and interleukin-6 (il-6) (proinflammatory genes) in larvae fed the diet with 0.02% GL were significantly lower than the control (P < 0.05). In conclusion, the supplementation of 0.005% -0.01% GL could enhance the expression of orexigenic factor genes, activities of digestive enzymes and antioxidant capacity, ultimately improving the survival, and growth performance of large yellow croaker larvae.

18.
Opt Express ; 29(3): 2984-3000, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33770907

RESUMO

In the development of a high-precision vertical Fizeau interferometer with a 300-mm aperture, the deformation of the transmission flat because of clamping and gravity must be considered. In this paper, we proposed a ring-point support scheme for the deformation calibration of a large-diameter transmission flat. The calibration theory of the ring-point support system with elastic deformation was derived. The changes in the surface and stress field of the transmission flat were analyzed quantitatively by finite element method modeling, leading to the optimization of the support structure. To validate the proposed calibration approach, we performed an absolute test of the transmission flat using a liquid reference. The test result was compared to a measurement of the Zygo interferometer demonstrating the effectiveness of the proposed ring-point support design. Finally, with the iterative deformation calibration, the accuracy of the transmission flat reached λ/25 (Peak Valley, PV) for a 300-mm aperture.

19.
BMC Biol ; 18(1): 8, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969153

RESUMO

BACKGROUND: Two-pore channels (TPCs) release Ca2+ from acidic intracellular stores and are implicated in a number of diseases, but their role in development is unclear. The social amoeba Dictyostelium discoideum proliferates as single cells that aggregate to form a multicellular organism on starvation. Starvation is sensed by the mTORC1 complex which, like TPC proteins, is found on acidic vesicles. Here, we address the role of TPCs in development and under starvation. RESULTS: We report that disruption of the gene encoding the single Dictyostelium TPC protein, TPC2, leads to a delay in early development and prolonged growth in culture with delayed expression of early developmental genes, although a rapid starvation-induced increase in autophagy is still apparent. Ca2+ signals induced by extracellular cAMP are delayed in developing tpc2- cells, and aggregation shows increased sensitivity to weak bases, consistent with reduced acidity of the vesicles. In mammalian cells, the mTORC1 protein kinase has been proposed to suppress TPC channel opening. Here, we show a reciprocal effect as tpc2- cells show an increased level of phosphorylation of an mTORC1 substrate, 4E-BP1. mTORC1 inhibition reverses the prolonged growth and increases the efficiency of aggregation of tpc2- cells. CONCLUSION: TPC2 is required for efficient growth development transition in Dictyostelium and acts through modulation of mTORC1 activity revealing a novel mode of regulation.


Assuntos
Canais de Cálcio/genética , Dictyostelium/fisiologia , Expressão Gênica , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Proteínas de Protozoários/genética , Autofagia , Canais de Cálcio/metabolismo , Dictyostelium/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas de Protozoários/metabolismo , Transdução de Sinais
20.
J Sci Food Agric ; 101(5): 2108-2116, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32978960

RESUMO

BACKGROUND: Heat-induced composite gels were prepared with 30 mg mL-1 pork myofibrillar protein (MP) and chickpea protein isolate (CPI) (0, 3, 6, 9, 12, and 15 g kg-1 ) in 0.6 mol L-1 NaCl, at pH 7.0. The gel strength, water-holding capacity, rheological properties, and microstructure of MP-CPI composite gels were investigated. RESULTS: Chickpea protein isolate improved (P < 0.05) gel strength and water-holding capacity of the MP composite gels. The rheological properties of MP-CPI composite gels were improved significantly by the addition of CPI. Meanwhile, the effects of CPI on the storage modulus of composite gels were positively correlated with the increased addition of CPI. Furthermore, according to low-field nuclear magnetic resonance (LF-NMR) results, the addition of CPI reduced the relaxation time of the composite gels and the relaxation peak area of free water, indicating that CPI could improve the water-holding capacity of MP-CPI composite gels. The microstructure of MP-CPI composite gels presented smaller and more uniform pores, which means that more water could be retained. CONCLUSION: The addition of chickpea protein isolate improved the gel strength, water-holding capacity, rheological properties, and microstructure of MP gels, indicating that CPI could be a potential protein additive to improve the microstructure, texture, and functional quality of meat products. © 2020 Society of Chemical Industry.


Assuntos
Cicer/química , Manipulação de Alimentos/métodos , Produtos da Carne/análise , Proteínas Musculares/química , Miofibrilas/química , Proteínas de Plantas/química , Animais , Aditivos Alimentares/química , Géis/química , Temperatura Alta , Músculo Esquelético/química , Carne Vermelha , Suínos
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