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1.
Appl Opt ; 63(4): 999-1006, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437397

RESUMO

In this paper, we investigate the energy efficiency optimization for a parallel relay-assisted underwater wireless optical communication (UWOC) system with simultaneous lightwave information and power transfer (SLIPT) over an aggregate channel. In this system, relay nodes are equipped with energy harvesting devices, getting energy from the direct current component of the received signal transmitted by the source node. These nodes utilize the harvested energy to transmit the signal to the destination node with the decoding and forwarding strategy. The harvested energy for each relay node is derived by the Gauss-Laguerre quadrature formula and the outage probability is deduced by the Meijer-G function. Then, the system's energy efficiency can be calculated and an energy efficiency maximization problem is built up with respect to the bias current. We propose a three-level-iteration algorithm to solve this problem. In the first level, the Dinkelbach method is used to represent energy efficiency in a parametric subtractive form. In the second level, we use the penalty function method to convert the object function and constraint. In the third level, the objective function is transformed into a quadratic function by using a successive convex approximate method, thereby solving for the bias current. The effects of system parameters on energy efficiency are also analyzed. Theoretical results and Monte Carlo simulations suggest that employing the solved bias current can significantly improve the system's energy efficiency.

2.
Neuroimage ; 283: 120437, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37924896

RESUMO

A cortical plasticity after long-duration single side deafness (SSD) is advocated with neuroimaging evidence while little is known about the short-duration SSDs. In this case-cohort study, we recruited unilateral sudden sensorineural hearing loss (SSNHL) patients and age-, gender-matched health controls (HC), followed by comprehensive neuroimaging analyses. The primary outcome measures were temporal alterations of varied dynamic functional network connectivity (dFNC) states, neurovascular coupling (NVC) and brain region volume at different stages of SSNHL. The secondary outcome measures were pure-tone audiograms of SSNHL patients before and after treatment. A total of 38 SSNHL patients (21 [55%] male; mean [standard deviation] age, 45.05 [15.83] years) and 44 HC (28 [64%] male; mean [standard deviation] age, 43.55 [12.80] years) were enrolled. SSNHL patients were categorized into subgroups based on the time from disease onset to the initial magnetic resonance imaging scan: early- (n = 16; 1-6 days), intermediate- (n = 9; 7-13 days), and late- stage (n = 13; 14-30 days) groups. We first identified slow state transitions between varied dFNC states at early-stage SSNHL, then revealed the decreased NVC restricted to the auditory cortex at the intermediate- and late-stage SSNHL. Finally, a significantly decreased volume of the left medial superior frontal gyrus (SFGmed) was observed only in the late-stage SSNHL cohort. Furthermore, the volume of the left SFGmed is robustly correlated with both disease duration and patient prognosis. Our study offered neuroimaging evidence for the evolvement from functional to structural brain alterations of SSNHL patients with disease duration less than 1 month, which may explain, from a neuroimaging perspective, why early-stage SSNHL patients have better therapeutic responses and hearing recovery.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Humanos , Masculino , Pessoa de Meia-Idade , Adulto , Feminino , Estudos de Coortes , Perda Auditiva Neurossensorial/diagnóstico por imagem , Perda Auditiva Súbita/diagnóstico por imagem , Perda Auditiva Súbita/complicações , Perda Auditiva Súbita/terapia , Audição , Neuroimagem , Estudos Retrospectivos
3.
Mol Med ; 29(1): 137, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37858064

RESUMO

BACKGROUND: Intestinal ischemia-reperfusion injury occurs in acute intestinal obstruction, intussusception, acute mesenteric artery embolism, and other diseases and can lead to local intestinal necrosis, distant organ involvement, or systemic reactions, with high morbidity and mortality. Ferroptosis plays a crucial role in intestinal ischemia-reperfusion injury, and inhibition of ferroptosis may provide new approaches for treating the disease. SIRT3 protects cells from oxidative stress and may be involved in the process of ferroptosis. We hypothesized that resveratrol, an agonist of SIRT3, could ameliorate intestinal ischemia-reperfusion injury by compensating the GSH/GPX4 pathway. METHODS: Intestinal ischemia-reperfusion (I/R) and Caco-2 hypoxia-reoxygenation models were established. Transmission electron microscopy was used to assess mitochondrial function; the Chiu's score was used to evaluate the degree of intestinal mucosal injury based on HE staining; and Western blot was used to detect the SIRT3/FoxO3a pathway, tight junction proteins and ferroptosis-related protein expression. Sirt3-/- C57, shSIRT3-Caco-2 cells and siFoxO3a-Caco-2 cells were established. C11-BODIPY was used to detect lipid peroxide in cells; FD4 and IFABP were used to detect intestinal permeability; MitoSOX was used to detect ROS levels; and MitoTracker and immunofluorescence colocalization were used to detect SIRT3 levels. RESULTS: In the intestinal I/R model, I/R injury occurs mainly during the reperfusion period and leads to ferroptosis through the GSH/GPX4 pathway. Resveratrol could reduce ferroptosis and ameliorate I/R injury by activating SIRT3. In Sirt3-/- mice, more intestinal mucosal cells underwent ferroptosis, I/R injury was more severe, and resveratrol lost the ability to ameliorate I/R injury. In addition, hypoxia-reoxygenation increased RSL3-induced ferroptosis sensitivity in Caco-2 cells in vitro. In the presence of shSIRT3 or RSL3 alone, resveratrol could ameliorate Caco-2 ferroptosis, but not RSL3-induced shSIRT3-Caco-2 ferroptosis. Furthermore, resveratrol might activate the SIRT3/FoxO3a pathway, increase the expression of SOD2 and catalase, and inhibit ROS generation, thus reducing lipid peroxidation and ferroptosis. CONCLUSION: To date, this is the first study to show that resveratrol ameliorates intestinal ischemia-reperfusion injury by activating SIRT3 and reducing ferroptosis. Resveratrol can reduce intestinal ischemia-reperfusion injury by activating the SIRT3/FoxO3a pathway, increasing the expression of SOD2 and catalase, reducing ROS and LPO production, compensating for the GSH/GPX4 pathway and inhibiting ferroptosis. Resveratrol increases the expression of SOD2 and catalase, reduces the production of ROS and LPO, compensates for the GSH/GPX4 pathway and inhibits ferroptosis by activating the SIRT3/FoxO3a pathway.


Assuntos
Ferroptose , Traumatismo por Reperfusão , Sirtuína 3 , Humanos , Camundongos , Animais , Resveratrol/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Catalase , Sirtuína 3/genética , Sirtuína 3/metabolismo , Células CACO-2 , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Hipóxia
4.
Microb Pathog ; 182: 106251, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37453481

RESUMO

Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is one of the major diseases restricting the development of large-scale pig breeding industry, which has brought huge economic losses to pig industry. Although a lot of work has been done in vaccine development, biosafety and pig health, PRRSV is characterized by easy mutation and recombination of genome, immunosuppression, enhanced antibody dependence, persistent infection, etc., making the prevention, control and elimination of PRRSV very difficult. With the deepening of PRRSV research, it is gradually realized that screening and identifying PRRSV susceptibility/resistance genes and implementing PRRSV disease resistance breeding are long-term and effective strategies for fundamental prevention and control, which has important practical significance for the prevention and control of pig herds.

5.
Virol J ; 20(1): 140, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37408066

RESUMO

Glycyrrhiza polysaccharide (GCP) is a natural plant active polysaccharide extracted from traditional Chinese medicine licorice. In this research, we studied the antiviral activity of glycyrrhiza polysaccharide against porcine reproductive and respiratory syndrome virus (PRRSV), a virus of the Arteriviridae family, with a high rate of variation and has caused huge economic losses to the pig industry in various countries since its discovery. Our results show that GCP can inhibit PRRSV replication in a dose-dependent manner. Furthermore, GCP could inhibit the mRNA expression of receptor genes CD163 and NF-κB p65 and promote the mRNA expression of the SLA-7 gene. Because of these results, GCP can be used as a candidate drug to prevent and treat PRRS.


Assuntos
Glycyrrhiza , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Suínos , Animais , Linhagem Celular , RNA Mensageiro , Replicação Viral
6.
Cell Biol Toxicol ; 39(3): 907-928, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35028790

RESUMO

Cervical spondylotic myelopathy (CSM) is a clinically symptomatic entity arising from the spinal cord compression by degenerative diseases. Although endoplasmic reticulum (ER) stress has been commonly observed in several neurodegenerative diseases, the relationship between ER stress and CSM remains unknown. Shikonin is known to protect PC12 by inhibiting apoptosis in vitro. This study hypothesised that ER stress was vital in neuronal apoptosis in CSM. Shikonin might inhibit such responses by regulating ER stress through the protein kinase-like ER kinase-eukaryotic translation initiation factor 2 α-subunit-C/EBP homologous protein (PERK-eIF2α-CHOP) signalling pathway. Thus, the aim of this study was evaluating the neuroprotective effect of shikonin in rats with double-level chronic cervical cord compression, as well as primary rat cortical neurons with glutamate-induced neurotoxicity. The result showed that ER stress-related upregulation of PERK-eIF2α-CHOP resulted in rat neuronal apoptosis after chronic cervical cord compression; then, shikonin promoted motor recovery and inhibited neuronal apoptosis by attenuating PERK-eIF2α-CHOP and prevented Bax translocation from cytoplasm to mitochondrion induced by CHOP of neurons in rats with chronic compression. Also, it was found that shikonin could protect rat primary cortical neuron against glutamate toxicity by regulating ER stress through the PERK-eIF2α-CHOP pathway in vitro. In conclusion, shikonin might inhibit neuronal apoptosis by regulating ER stress through attenuating the activation of PERK-eIF2α-CHOP.


Assuntos
Medula Cervical , Compressão da Medula Espinal , Ratos , Animais , Compressão da Medula Espinal/tratamento farmacológico , Medula Cervical/metabolismo , Estresse do Retículo Endoplasmático , Apoptose , Fator de Iniciação 2 em Eucariotos/metabolismo , eIF-2 Quinase/metabolismo
7.
Surg Today ; 53(4): 459-469, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36436022

RESUMO

PURPOSE: This study surveyed the current practice of surgical treatment of obstructive left-sided colon cancer (OLCC) in China. METHODS: All colorectal surgery departments at tertiary or secondary hospitals in China were invited to complete a web-based questionnaire between August 27 and September 2, 2020. RESULTS: Overall, completed questionnaire were received from 357 hospitals. Emergency surgery was the mainstay of treatment for OLCC, with the open approach accounting for up to 61.62%. The stoma rate of emergency surgery was up to 80%, mainly due to inadequate bowel preparation and severe edema of colon walls. Hartmann's procedure (61.62%) was the most preferred operation. A total of 243 hospitals (68.7%) reported that they would consider the use of a self-expanding metallic stent (SEMS) as a bridge for elective surgery. More than 50% of the hospitals participating in this study reported the success rate of SEMS placement, as well as the resolution rate of obstruction more than 80%, and the stent-related perforation rate was < 5%. A total of 126 hospitals considered carrying out a strategy of SEMS followed by neoadjuvant chemotherapy prior to elective surgery and believed that it might further improve treatment outcomes. CONCLUSIONS: SEMS is a feasible option for the treatment of OLCC in addition to traditional emergency surgery, and its clinical benefits have been preliminarily recognized.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Obstrução Intestinal , Humanos , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/complicações , Estudos Transversais , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Neoplasias do Colo/cirurgia , Neoplasias do Colo/complicações , Stents , Resultado do Tratamento , Estudos Retrospectivos
8.
Clin Oral Investig ; 27(9): 5153-5170, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37428274

RESUMO

OBJECTIVES: We aimed to explore the osteogenic potential of periodontal ligament stem cells (PDLSCs) in bioprinted methacrylate gelatine (GelMA) hydrogels in vitro and in vivo. MATERIALS AND METHODS: PDLSCs in GelMA hydrogels at various concentrations (3%, 5%, and 10%) were bioprinted. The mechanical properties (stiffness, nanostructure, swelling, and degradation properties) of bioprinted constructs and the biological properties (cell viability, proliferation, spreading, osteogenic differentiation, and cell survival in vivo) of PDLSCs in bioprinted constructs were evaluated. Then, the effect of bioprinted constructs on bone regeneration was investigated using a mouse cranial defect model. RESULTS: Ten percent GelMA printed constructs had a higher compression modulus, smaller porosity, lower swelling rate, and lower degradation rate than 3% GelMA. PDLSCs in bioprinted 10% GelMA bioprinted constructs showed lower cell viability, less cell spreading, upregulated osteogenic differentiation in vitro, and lower cell survival in vivo. Moreover, upregulated expression of ephrinB2 and EphB4 protein and their phosphorylated forms were found in PDLSCs in 10% GelMA bioprinted constructs, and inhibition of eprhinB2/EphB4 signalling reversed the enhanced osteogenic differentiation of PDLSCs in 10% GelMA. The in vivo experiment showed that 10% GelMA bioprinted constructs with PDLSCs contributed to more new bone formation than 10% GelMA constructs without PDLSCs and constructs with lower GelMA concentrations. CONCLUSIONS: Bioprinted PDLSCs with high-concentrated GelMA hydrogels exhibited enhanced osteogenic differentiation partially through upregulated ephrinB2/EphB4 signalling in vitro and promoted bone regeneration in vivo, which might be more appropriate for future bone regeneration applications. CLINICAL RELEVANCE: Bone defects are a common clinical oral problem. Our results provide a promising strategy for bone regeneration through bioprinting PDLSCs in GelMA hydrogels.


Assuntos
Hidrogéis , Osteogênese , Hidrogéis/farmacologia , Hidrogéis/química , Hidrogéis/metabolismo , Ligamento Periodontal , Gelatina/farmacologia , Gelatina/química , Gelatina/metabolismo , Células-Tronco , Regeneração Óssea , Diferenciação Celular , Células Cultivadas
9.
J Environ Manage ; 325(Pt B): 116588, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36308954

RESUMO

Nowadays, groundwater quality has deteriorated because of intensive human activities. It is important to accurately identify the pollution source for controlling the deterioration of groundwater quality. However, the accuracy of the current source analysis method needs to be improved. In this study, we combined hydrochemical method, isotope tracing technique and PMF model, for the first time, to trace the source of groundwater pollution in Beichuan River basin, Qinghai Province, China. According to the results, there were 35.8% of Fe, 34.1% of total hardness, 24.3% of SO42- and 8.09% of NO3- samples exceeded the Grade III standards for Groundwater quality in China, which indicated that the groundwater in the study area has been significantly affected by human activities. Hydrochemical method suggested that the chemical component originated from rock weathering, cation exchange and mineral dissolution. Based on isotope tracing technique (δ15N-NO3-, δ18O-NO3-, δ34S-SO42- and δ18O-SO42-), the primary sources of nitrate and sulfate in groundwater were soil nitrogen and oxidation of sulfide minerals in the forest area, domestic sewage and oxidation of sulfide minerals in the urban and industrial area, and mixed sources in the village and agricultural area. Finally, the pollution source of groundwater was distinguished by combining the PMF model, isotope tracing technique and hydrochemical method. Results showed that the main pollutant of groundwater is domestic sewage in the urban, village and industrial area. The contribution rates to groundwater pollution were 60.7%, 60.8% and 57.8%, respectively. However, in the forest and agricultural area, the main source changed to water-rock interaction and chemical fertilizer, and the contribution rates to groundwater quality were 53.5% and 61.0%, respectively. Our results suggested that the coupling tracing methodology can improve the accuracy of source resolution in the water environment and it can be applied to other areas of the world.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Humanos , Esgotos/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Isótopos de Nitrogênio/análise , Nitratos/análise , Sulfetos/análise , Água/análise , China
10.
Curr Issues Mol Biol ; 44(10): 4822-4837, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36286043

RESUMO

Atherosclerosis is a major risk factor for type 2 diabetes (T2D) mortality. We aim to investigate the changes in miR-21, miR-122, miR-33a and miR-3064-5p in circulation and the liver of ApoE-/- mice with streptozocin (STZ)-induced T2D. Twenty 5-week-old male ApoE-/- mice were randomly assigned to the control (n = 10) and T2D group (n = 10) and intraperitoneally injected with a citrate buffer and streptozotocin (STZ) (40 mg/kg BW) once a day for three consecutive days. The successfully STZ-induced T2D mice (n = 5) and control mice (n = 5) were then fed with a high-fat diet (HFD) for 34 weeks. Compared to the control mice, ApoE-/- mice with STZ-induced T2D had slower (p < 0.05) growth, increased (p < 0.05) total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), decreased (p < 0.05) high-density lipoprotein cholesterol (HDL-C) in serum, reduced (p < 0.05) TC and sterol regulatory element-binding protein-2 (Srebp-2), elevated (p < 0.05) ATP-binding-cassette-transporter-A1 (Abca1) in the liver, aggravated (p < 0.05) atherosclerotic lesions in the aorta, downregulated (p < 0.05) miR-21 and miR-33a, and upregulated (p < 0.05) miR-122 and miR-3064-5p in serum and the liver. In addition, the aortic lesions showed a positive correlation with miR-122 (r = 1.000, p = 0.001) and a negative correlation with miR-21 (r = −1.000, p = 0.001) in ApoE-/- mice with T2D. In conclusion, T2D-accelerated atherosclerosis correlates with a reduction in miR-21 and miR-33a and an elevation in miR-122 and miR-3064-5p in circulation and the liver of ApoE-/- mice.

11.
Opt Express ; 30(22): 39492-39509, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298900

RESUMO

In this paper, we investigate joint subchannel assignment and power allocation for the energy efficiency (EE) optimization in an indoor visible light communication (VLC)-Internet of Things (IoT) system with simultaneous lightwave information and power transfer (SLIPT). A mixed-integer fractional nonlinear programming problem that is challenging to solve is formulated. To tackle this problem, the optimal transmission scheme is decomposed into subchannel assignment and power allocation. Firstly, a virtual cell formation and subchannel assignment (VCF-SA) scheme is proposed, which considers the location of IoT devices, quality of service requirements, and energy states. Secondly, a quadratic transformation-based power allocation (QTBPA) scheme is designed to transform the fractional nonlinear programming problem into a series of convex problems that can be solved iteratively. Simulation results illustrate the effectiveness of the proposed scheme in terms of system EE compared to the benchmarks. The impact of system parameters on the EE is also analyzed.

12.
Neurochem Res ; 47(7): 2064-2075, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35538293

RESUMO

Ischemic stroke is a grievous intimidation to the healthiness of sufferers. Previous studies have reported that dexmedetomidine (DEX) has a protective effect on a variety of organs. This paper aimed to explore the regulatory mechanism of DEX in ischemic stroke through miR-665/ROCK2 axis. The mice model of ischemic stroke was constructed by middle cerebral artery occlusion (MCAO). The cell model of ischemic stroke was constructed by oxygen-glucose deprivation (OGD). Cell viability and apoptosis were assessed by CCK-8 assay and flow cytometry. The expression of cytokines was detected by ELISA. Lactate dehydrogenase (LDH) concentration was evaluated by LDH kit. The cerebral infarct volume of MCAO mice was detected by TTC staining, and the apoptosis of brain cells was detected by TUNEL staining. The target relationship between ROCK2 and miR-665 was analyzed by dual-luciferase reporter assay. DEX contributed cell viability from 42 to 66% (1 µM) and restrained cell apoptosis from 26 to 18% in HT22 cells treated with OGD (P < 0.01). Meanwhile, DEX decreased the expression of cytokines and LDH concentration from 184 to 126% (P < 0.001). Moreover, the expression of miR-665 enhanced 2.9 times (P < 0.05) and the expression of ROCK2 (P < 0.05) and NF-κB p65 (P < 0.01) reduced 1.8 times and 2.2 times after DEX treatment in OGD induced HT22. And miR-665 knockdown attenuated the effect of DEX on inflammation damage (the levels of TNF-α, IL-1ß and IL-6 increased 1.36 times, 1.31 times, 1.43 time, respectively, and IL-10 decreased 1.68 times) and apoptosis from 17 to 25% (P < 0.01). MiR-665 directly targeted ROCK2 and regulated ROCK2 and NF-κB p65 expression (P < 0.01). Furthermore, ROCK2 overexpression inhibited the protective effect of DEX in HT22 induced by OGD (P < 0.001), while miR-665 overexpression reversed the regulatory of ROCK2 (P < 0.01). In vivo, DEX decreased cerebral infarction volume and inhibited apoptosis of brain cell (P < 0.001). DEX has a protective effect in ischemic stroke by promoting miR-665 expression to downregulate ROCK2/NF-κB axis, suggesting DEX has a beneficial effect on ischemic stroke and miR-665 is a conceivable target for the therapeutics and diagnosis of ischemic stroke.


Assuntos
Isquemia Encefálica , Dexmedetomidina , AVC Isquêmico , MicroRNAs , Traumatismo por Reperfusão , Animais , Apoptose , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Citocinas/metabolismo , Dexmedetomidina/farmacologia , Dexmedetomidina/uso terapêutico , Glucose/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Camundongos , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Regulação para Cima , Quinases Associadas a rho/metabolismo
13.
Langmuir ; 38(48): 14879-14890, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36399773

RESUMO

The remediation of environmental boron contamination has received extensive research attention. The adsorbent ECH@NGM aerogel with high hydrophilic and mechanical properties was synthesized to remove boron. The ECH@NGM aerogel had a high adsorption capacity of 81.11 mg/g, which was 14.50% higher than that of commercial boron-selective resin Amberlite IRA743. The Freundlich model and pseudo-second-order model described the adsorption behavior well. In addition, the response surface methodology (RSM) could predict the experimental outcomes and optimize the reaction conditions, and X-ray photoelectron spectroscopy (XPS) and control tests were utilized to investigate probable adsorption mechanisms. These data showed that the B ← N coordination bond was the primary adsorption force. The adsorbent had good resistance to interference from coexisting salts, high reusability, good adsorption performance even after five reuse cycles, and a high desorption rate in a relatively short time. The adsorption performance in real brines could be maintained at 80%. Therefore, this work not only provided ECH@NGM aerogels for the removal of boron from brine but also elucidated the main adsorption processes between N-containing adsorbents and boron, facilitating the design of future adsorbents for boron removal.

14.
Nucleic Acids Res ; 48(5): 2220-2231, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32020194

RESUMO

Hybridization chain reaction (HCR) was a significant discovery for the development of nanoscale materials and devices. One key challenge for HCR is the vulnerability to background leakage in the absence of the initiator. Here, we systematically analyze the sources of leakage and refine leak-resistant rule by using molecular thermodynamics and dynamics, biochemical and biophysical methods. Transient melting of DNA hairpin is revealed to be the underlying cause of leakage and that this can be mitigated through careful consideration of the sequence thermodynamics. The transition threshold of the energy barrier is proposed as a testing benchmark of leak-resistance DNA hairpins. The universal design of DNA hairpins is illustrated by the analysis of hsa-miR-21-5p as biomarker when used in conjunction with surface-enhanced Raman spectroscopy. We further extend the strategy for specific signal amplification of miRNA homologs. Significantly, it possibly provides a practical route to improve the accuracy of DNA self-assembly for signal amplification, and that could facilitate the development of sensors for the sensitive detection of interest molecules in biotechnology and clinical medicine.


Assuntos
DNA/química , Sequências Repetidas Invertidas , MicroRNAs/química , Hibridização de Ácido Nucleico/métodos , Pareamento de Bases , Benchmarking , DNA/genética , DNA/metabolismo , Exossomos/química , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Simulação de Dinâmica Molecular , Conformação de Ácido Nucleico , Desnaturação de Ácido Nucleico , Análise Espectral Raman , Termodinâmica , Neoplasias da Bexiga Urinária/química , Neoplasias da Bexiga Urinária/urina
15.
Zhonghua Nan Ke Xue ; 28(5): 415-421, 2022 May.
Artigo em Zh | MEDLINE | ID: mdl-37477480

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of black tomato concentrate (BTC), which is rich in polyphenols, in the treatment of ED. METHODS: We conducted a prospective randomized open clinical study of 150 ED patients from December 2018 to February 2020, and treated the them with placebo (n = 50), BTC (n = 50) and Compound Xuanju Capsules (CXC) (n = 50), respectively, all for 8 weeks. Before and at 4 and 8 weeks after treatment, we obtained the scores of the patients on IIEF-5, Erection Hardness Score (EHS), Sexual Encounter Profile (SEP-2,3) and General Assessment Questionnaire (GAQ-1,2), related biochemical indexes and the T level, followed by comparison among the three groups. RESULTS: Totally, 120 of the patients completed the clinical trial, 37 in the placebo, 43 in the BTC and 40 in the CXC group. There were no statistically significant differences among the placebo, BTC and CXC groups in the baseline scores on IIEF-5 (12.03 �� 3.50 vs 11.70 �� 3.80 vs 11.42 �� 3.82), EHS, and SEP-2,3 (P > 0.05). At 8 weeks after treatment, the patients in the BTC group showed significant improvement in IIEF-5 (15.67 �� 3.63), EHS, SEP-2,3 and GAQ-1 positive response compared with those in the placebo group (P < 0.05) and similar improvement to that in the CXC group in IIEF-5 (15.67 �� 3.63 vs 15.65 �� 3.87), EHS, SEP-2,3 and GAQ-1,2 (P > 0.05). No statistically significant differences were observed in the incidence of adverse reactions among the placebo, BTC and CXC groups (4.7% vs 2.7% vs 5.0%, P > 0.05), and the symptoms were significantly relieved in the BTC group after change of the administration time to after meal. CONCLUSION: Black tomato concentrate is comparable to Compound Xuanju Capsules and better than placebo (P < 0.05) in improving the IIEF-5, EHS and SEP-2,3 scores of ED patients. And, with a high safety, it can be used as an alternative treatment of ED.


Assuntos
Disfunção Erétil , Solanum lycopersicum , Masculino , Humanos , Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/etiologia , Ereção Peniana , Cápsulas/uso terapêutico , Estudos Prospectivos , Resultado do Tratamento , Método Duplo-Cego
16.
J Hepatol ; 74(6): 1295-1302, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33347952

RESUMO

BACKGROUND & AIMS: The evolution and clinical significance of abnormal liver chemistries and the impact of hepatitis B infection on outcome in patients with COVID-19 is not well characterized. This study aimed to explore these issues. METHODS: This large retrospective cohort study included 2,073 patients with coronavirus disease 2019 (COVID-19) and definite outcomes in Wuhan, China. Longitudinal liver function tests were conducted, with associated factors and risk of death determined by multivariate regression analyses. A prognostic nomogram was formulated to predict the survival of patients with COVID-19. The characteristics of liver abnormalities and outcomes of patients with COVID-19, with and without hepatitis B, were compared after 1:3 propensity score matching. RESULTS: Of the 2,073 patients, 1,282 (61.8%) had abnormal liver chemistries during hospitalization, and 297 (14.3%) had a liver injury. The mean levels of aspartate aminotransferase (AST) and direct bilirubin (D-Bil) increased early after symptom onset in deceased patients and showed disparity compared to levels in discharged patients throughout the clinical course of the disease. Abnormal AST (adjusted hazard ratio [HR] 1.39; 95% CI 1.04-1.86, p = 0.027) and D-Bil (adjusted HR 1.66; 95% CI 1.22-2.26; p = 0.001) levels at admission were independent risk factors for mortality due to COVID-19. A nomogram was established based on the results of multivariate analysis and showed sufficient discriminatory power and good consistency between the prediction and the observation. HBV infection in patients did not increase the risk of poor COVID-19-associated outcomes. CONCLUSIONS: Abnormal AST and D-Bil levels at admission were independent predictors of COVID-19-related mortality. Therefore, monitoring liver chemistries, especially AST and D-Bil levels, is necessary in hospitalized patients with COVID-19. LAY SUMMARY: Liver test abnormalities (in particular elevations in the levels of aspartate aminotransferase [AST] and direct bilirubin [D-Bil]) were observed after symptom onset in patients who went on to die of coronavirus disease 2019 (COVID-19). Abnormal levels of AST and D-Bil at admission were independent predictors of COVID-19-related mortality. HBV infection in patients did not increase the risk of poor COVID-19-associated outcomes.


Assuntos
Aspartato Aminotransferases/sangue , Bilirrubina/sangue , COVID-19/mortalidade , Mortalidade Hospitalar , Hepatopatias/complicações , SARS-CoV-2 , Idoso , Feminino , Hepatite B/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Estudos Retrospectivos
17.
Opt Express ; 29(9): 14016-14024, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33985127

RESUMO

Realizing vector spatiotemporal solitons that are stable in high dimensions is a long-standing goal in the study of nonlinear optical physics. Here, a scheme is proposed to generate three-dimensional (3D) vector spatiotemporal solitons in a cold atomic system with linear and nonlinear parity-time (PT) potentials by utilizing electromagnetically induced transparency (EIT). We investigate the existence and stability of these vector 3D semilunar solitons (SSs) and vortex solitons (VSs) supported by the linear and nonlinear PT potentials. The results show that these solitons have extremely low generation power and very slow propagation velocity and can stably propagate with constant total energy in this system. The frontal head-on collisions of two vector solitons feature quasi-elastic collisions. The dynamics characteristics of these solitons depend on the linear and nonlinear PT-symmetric potential parameters, in particular, the imaginary part of PT potentials. Our study provides a new route for manipulating high-dimensional nonlinear vector optical signals via the controlled optical linear and nonlinear potentials in cold atomic gases.

18.
Int J Med Sci ; 18(11): 2366-2371, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33967613

RESUMO

Coronavirus Disease 2019 (COVID-19) emerges as a global pandemic and there is a lack of evidence about the clinical course and outcome of patients on maintenance hemodialysis (MHD). Here we conducted a retrospective longitudinal study aimed to analyze the clinical features and outcome of MHD patients hospitalized with COVID-19. Of 3126 inpatients with COVID-19 at 3 Branches of Wuhan Tongji Hospital from Jan 18th to Mar 9th, 2020, 19 patients were undergoing maintenance hemodialysis. Among the 19 MHD patients with COVID-19, 6 patients (31.6%) died, and 13 patients (68.4%) were able to be discharged. Baseline characteristics, clinical courses, laboratory findings, and dynamic trajectories of major laboratory markers were compared between survivors and nonsurvivors. According to our findings, MHD patients with COVID-19 who experienced non-surviving outcome had more elevated CRP, IL6 and procalcitonin as well as fibrinogen levels at various points compared to survivors. Thus the dysregulation of immune response as well as coagulation abnormalities might be highly involved in the pathological process of COVID-19, contributing to the poor prognosis in MHD patients.


Assuntos
COVID-19/etiologia , Falência Renal Crônica/complicações , Diálise Renal , SARS-CoV-2 , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , COVID-19/imunologia , Feminino , Hospitalização , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tratamento Farmacológico da COVID-19
19.
J Nanobiotechnology ; 19(1): 273, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34496881

RESUMO

The control of contagious or refractory diseases requires early, rapid diagnostic assays that are simple, fast, and easy-to-use. Here, easy-to-implement CRISPR/Cas12a-based diagnostic platform through Raman transducer generated by Raman enhancement effect, term as SERS-CRISPR (S-CRISPR), are described. The S-CRISPR uses high-activity noble metallic nanoscopic materials to increase the sensitivity in the detection of nucleic acids, without amplification. This amplification-free platform, which can be performed within 30-40 min of incubation time, is then used for detection of SARS-CoV-2 derived nucleic acids in RNA extracts obtained from nasopharyngeal swab specimens (n = 112). Compared with the quantitative reverse transcription polymerase chain reaction (RT-qPCR), the sensitivity and specificity of S-CRISPR reaches 87.50% and 100%, respectively. In general, the S-CRISPR can rapidly identify the RNA of SARS-CoV-2 RNA without amplification and is a potential strategy for nucleic acid point of care test (POCT).


Assuntos
Sistemas CRISPR-Cas/genética , Técnicas de Amplificação de Ácido Nucleico , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Análise Espectral Raman , COVID-19/diagnóstico , COVID-19/virologia , Regulação Fúngica da Expressão Gênica , Genes Virais , Humanos , RNA Viral/análise , Sensibilidade e Especificidade
20.
J Dairy Sci ; 104(1): 981-988, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33131827

RESUMO

Previous studies suggest that there exists a lag relationship between daily milk yield and heat stress. The values of heat stress indicators (e.g., temperature-humidity index and ambient temperature) before test day have a simple correlation with daily milk yield on test day. However, the simple correlation might not be the best description because daily milk yield and heat stress indicators have a nature of time series in common, and their correlations are cross correlations that could be affected by autocorrelations. We hope to give a more reliable estimation on the lag relationship of daily milk yield via excluding autocorrelations with transfer function modeling. In this study, we found a lag relationship between daily milk yield and heat stress indicators based on transfer function modeling. Heat stress indicators included ambient temperature and temperature-humidity index. The daily milk yield data from 123 cows were obtained during a consecutive 63-d period (July 10-September 10, 2016). The mean daily milk yield (MY) and the maximum daily ambient temperature (TA_max) satisfied the stationary hypothesis, and the cross correlation between them was calculated. Before excluding autocorrelation, MY at 0 to 4 d after test day had significant cross correlations with TA_max on test day. After excluding the influence of autocorrelations, MY at 1 to 3 d after the test day had significant cross correlations with TA_max on test day. This result suggested that MY would respond to TA_max 1 d after the test day. In addition, the strength of cross correlations between MY and TA_max decreased from 1 to 3 d in sequence, implying a declining lag response of MY that would last for 3 d. The transfer function model for MY and TA_max is written as: MYt = 16.90 + 0.74MYt- 1 - 0.25TA_maxt- 1 + Nt, where Nt is white noise. This model can be used to track and predict the dynamic response of MY to TA_max.


Assuntos
Doenças dos Bovinos/fisiopatologia , Transtornos de Estresse por Calor/veterinária , Lactação , Animais , Bovinos , Feminino , Transtornos de Estresse por Calor/fisiopatologia , Resposta ao Choque Térmico , Umidade , Lactação/fisiologia , Leite , Temperatura , Fatores de Tempo
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