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1.
Brief Bioinform ; 24(1)2023 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-36567622

RESUMEN

Genomic recombination is an important driving force for viral evolution, and recombination events have been reported for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the Coronavirus Disease 2019 pandemic, which significantly alter viral infectivity and transmissibility. However, it is difficult to identify viral recombination, especially for low-divergence viruses such as SARS-CoV-2, since it is hard to distinguish recombination from in situ mutation. Herein, we applied information theory to viral recombination analysis and developed VirusRecom, a program for efficiently screening recombination events on viral genome. In principle, we considered a recombination event as a transmission process of ``information'' and introduced weighted information content (WIC) to quantify the contribution of recombination to a certain region on viral genome; then, we identified the recombination regions by comparing WICs of different regions. In the benchmark using simulated data, VirusRecom showed a good balance between precision and recall compared to two competing tools, RDP5 and 3SEQ. In the detection of SARS-CoV-2 XE, XD and XF recombinants, VirusRecom providing more accurate positions of recombination regions than RDP5 and 3SEQ. In addition, we encapsulated the VirusRecom program into a command-line-interface software for convenient operation by users. In summary, we developed a novel approach based on information theory to identify viral recombination within highly similar sequences, providing a useful tool for monitoring viral evolution and epidemic control.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Teoría de la Información , Filogenia , Recombinación Genética
2.
Virol J ; 21(1): 132, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844968

RESUMEN

Tetraparvovirus is an emerging parvovirus infecting a variety of mammals and humans, and associated with human diseases including severe acute respiratory infection and acute encephalitis syndrome. In the present study, a Tetraparvovirus ungulate 1 (formerly known as bovine hokovirus) strain HNU-CBY-2023 was identified and characterized from diseased Chinese Simmental from Hunan province, China. The nearly complete genome of HNU-CBY-2023 is 5346 nt in size and showed genomic identities of 85-95.5% to the known Tetraparvovirus ungulate 1 strains from GenBank, indicating a rather genetic variation. Phylogenetic and genetic divergence analyses indicated that Tetraparvovirus ungulate 1 could be divided into two genotypes (I and II), and HNU-CBY-2023 was clustered into genotype II. This study, for the first time, identified Tetraparvovirus ungulate 1 from domestic cattle from mainland China, which will be helpful to understand the prevalence and genetic diversity of Tetraparvovirus ungulate 1.


Asunto(s)
Enfermedades de los Bovinos , Variación Genética , Genoma Viral , Genotipo , Infecciones por Parvoviridae , Filogenia , Animales , Bovinos , China , Enfermedades de los Bovinos/virología , Enfermedades de los Bovinos/epidemiología , Infecciones por Parvoviridae/veterinaria , Infecciones por Parvoviridae/virología , Infecciones por Parvoviridae/epidemiología , Genoma Viral/genética , Parvovirinae/genética , Parvovirinae/aislamiento & purificación , Parvovirinae/clasificación , Análisis de Secuencia de ADN , ADN Viral/genética , Pueblos del Este de Asia
3.
J Med Virol ; 95(1): e28116, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36056469

RESUMEN

Increasing evidence supports inter-species transmission of SARS-CoV-2 variants from humans to domestic or wild animals during the ongoing COVID-19 pandemic, which is posing great challenges to epidemic control. Clarifying the host range of emerging SARS-CoV-2 variants will provide instructive information for the containment of viral spillover. The spike protein (S) of SARS-CoV-2 is the key determinant of receptor utilization, and therefore amino acid mutations on S will probably alter viral host range. Here, to evaluate the impact of S mutations, we tested 27 pseudoviruses of SARS-CoV-2 carrying different spike mutants by infecting Hela cells expressing different angiotensin-converting enzyme 2 (ACE2) orthologs from 20 animals. Of these 27 pseudoviruses, 20 bear single mutation and the other 7 were cloned from emerging SARS-CoV-2 variants, including D614G, Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), Lambda (B.1.429), and Mu (B.1.621). Using pseudoviral reporter assay, we identified that the substitutions of T478I and N501Y enabled the pseudovirus to utilize chicken ACE2, indicating potential infectivity to avian species. Furthermore, the S mutants of real SARS-CoV-2 variants comprising N501Y showed significantly acquired abilities to infect cells expressing mouse ACE2, indicating a critical role of N501Y in expanding SARS-CoV-2 host range. In addition, A262S and T478I significantly enhanced the utilization of various mammal ACE2. In summary, our results indicated that T478I and N501Y substitutions were two S mutations important for receptor adaption of SARS-CoV-2, potentially contributing to the spillover of the virus to many other animal hosts. Therefore, more attention should be paid to SARS-CoV-2 variants with these two mutations.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Animales , Ratones , SARS-CoV-2/genética , Enzima Convertidora de Angiotensina 2/genética , Células HeLa , Especificidad del Huésped , Pandemias , Glicoproteína de la Espiga del Coronavirus/genética , Mutación , Unión Proteica , Mamíferos
4.
J Med Virol ; 95(1): e28407, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36519597

RESUMEN

To control the ongoing COVID-19 pandemic, a variety of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines have been developed. However, the rapid mutations of SARS-CoV-2 spike (S) protein may reduce the protective efficacy of the existing vaccines which is mainly determined by the level of neutralizing antibodies targeting S. In this study, we screened prevalent S mutations and constructed 124 pseudotyped lentiviral particles carrying these mutants. We challenged these pseudoviruses with sera vaccinated by Sinovac CoronaVac and ZF2001 vaccines, two popular vaccines designed for the initial strain of SARS-CoV-2, and then systematically assessed the susceptivity of these SARS-CoV-2 variants to the immune sera of vaccines. As a result, 14 S mutants (H146Y, V320I + S477N, V382L, K444R, L455F + S477N, L452M + F486L, F486L, Y508H, P521R, A626S, S477N + S698L, A701V, S477N + T778I, E1144Q) were found to be significantly resistant to neutralization, indicating reduced protective efficacy of the vaccines against these SARS-CoV-2 variants. In addition, F486L and Y508H significantly enhanced the utilization of human angiotensin-converting enzyme 2, suggesting a potentially elevated infectivity of these two mutants. In conclusion, our results show that some prevalent S mutations of SARS-CoV-2 reduced the protective efficacy of current vaccines and enhance the infectivity of the virus, indicating the necessity of vaccine renewal and providing direction for the development of new vaccines.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevención & control , Anticuerpos Antivirales , Pruebas de Neutralización , Glicoproteína de la Espiga del Coronavirus , Internalización del Virus , Pandemias , Anticuerpos Neutralizantes , Mutación
5.
J Environ Manage ; 320: 115800, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35933877

RESUMEN

This paper presents a CFD modeling of deNOx process in a coal-fired power plant selective catalytic reduction (SCR) system, with focus on the transient hydrodynamics of multi-species flow and the influence of vortex on the deNOx process. For this purpose, a comprehensive CFD model is established, parameter study and model validation are performed, and the hydrodynamics, vortex evolution and species concentration distribution are numerically investigated. Simulation results indicate that many vortices with various scale/intensity/shape exist in the SCR system, causing apparent pressure pulsations and velocity fluctuations. High-intensity eddies are mainly distributed in the deflector group Ι, the NH3 nozzles, the static mixer, and the right part of the rectifying grille. The number of eddies decreases significantly with reducing the unit loads. Affected by vortex evolution, the NH3 concentration fluctuates in the SCR system, especially in the vertical flue. The deNOx process completes within 6 s, and the ammonia slip is less than 1.0 ppm, which well meets the requirement of industrial standards. In addition, the static mixer severely destroys the velocity uniformity but favors the mixing of NH3 and NOx. The rectifying grille improves the uniformity of flow field and species concentration field significantly.


Asunto(s)
Contaminantes Atmosféricos , Carbón Mineral , Contaminantes Atmosféricos/análisis , Catálisis , Hidrodinámica , Centrales Eléctricas
6.
Arch Virol ; 166(5): 1455-1462, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33704558

RESUMEN

During the dengue epidemic in Yunnan Province, China, during 2019, a concurrent outbreak of chikungunya occurred in the city of Ruili, which is located in the southwest of the province, adjacent to Myanmar. As part of this outbreak, three neonatal cases of infection with indigenous chikungunya virus from mother-to-child (vertical) transmission were observed. Isolates of chikungunya virus were obtained from 37 serum samples of patients with chikungunya during this outbreak, and a phylogenetic analysis of these isolates revealed that they belong to the Indian Ocean subclade of the East/Central/South African genotype. The E1 genes of these viruses did not harbor the A226V mutation.


Asunto(s)
Fiebre Chikungunya/virología , Virus Chikungunya/aislamiento & purificación , Enfermedades Transmisibles Emergentes/virología , Transmisión Vertical de Enfermedad Infecciosa , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/transmisión , Virus Chikungunya/clasificación , Virus Chikungunya/genética , China/epidemiología , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/transmisión , Brotes de Enfermedades , Femenino , Genoma Viral/genética , Genotipo , Humanos , Masculino , Mutación , Filogenia , ARN Viral/genética , Proteínas Virales/genética
7.
Paediatr Anaesth ; 30(1): 57-62, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31742846

RESUMEN

BACKGROUND: Children with severe obstructive sleep apnea syndrome (OSAS) are more sensitive to opioids. Identifying such children and reducing or even eliminating opioids are necessary but difficult. We have previously shown that patients sensitive to intraoperative fentanyl require less opioids postoperatively. AIM: The objective of this study was to evaluate the performance of a postinduction fentanyl test in identifying severe obstructive sleep apnea syndrome. METHODS: A prospective, observational, assessor-blinded study was carried out with 104 sleep study assessed children undergoing elective adenotonsillectomy. Intravenous fentanyl (1 µg/kg) was administered as a test in nonpremedicated, spontaneously breathing, sevoflurane-induced patients before endotracheal intubation. The respiratory rates before and after fentanyl administration were studied. The primary outcome was the sensitivity and specificity of the postinduction fentanyl test in identifying severe OSAS compared with polysomnography. RESULTS: A postinduction fentanyl test had a likelihood ratio of 7.2 (95% CI: 3.6-14.6) and an area under the curve value of 0.896 (95% CI: 0.821-0.947) to identify severe obstructive sleep apnea syndrome. The pragmatic cut-off value for the postinduction fentanyl test was found to be 50%. Using a reduction in respiratory rate of >50%, the postinduction fentanyl test detected severe OSAS with a sensitivity of 87%, a specificity of 88%, a positive predictive value of 85%, and a negative predictive value of 89%. CONCLUSION: Our study showed that a postinduction fentanyl test had good predictive value in identifying severe obstructive sleep apnea syndrome and early postoperative adverse respiratory events and could provide a reference for postoperative analgesia in children undergoing adenotonsillectomy.


Asunto(s)
Fentanilo/administración & dosificación , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/cirugía , Adenoidectomía , Anestesia General , Niño , Preescolar , Femenino , Humanos , Masculino , Atención Perioperativa , Periodo Posoperatorio , Estudios Prospectivos , Frecuencia Respiratoria , Tonsilectomía
8.
Microvasc Res ; 123: 74-80, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30611747

RESUMEN

Mesenchymal stem cells can be used as a novel treatment of ischemic stroke, but their therapeutic effect and mechanism of action require further evaluation. Mitochondrial dysfunction has core functions in ischemia-reperfusion stroke injury. Our recent research has demonstrated that mesenchymal stem cells can transfer their functional mitochondria to injured endothelial cells via tunneling nanotubes in vitro, resulting in the rescue of aerobic respiration and protection of endothelial cells from apoptosis. Therefore, we presume that the mechanisms of mitochondrial protection may be involved in stem cell-mediated rescue of injured cerebral microvasculature and recovery from ischemic stroke. In this study, the middle cerebral artery occlusion and reperfusion surgery were conducted on rats, and mesenchymal stem cells were then engrafted into the injured cerebrovascular system. Our results showed that the host cells of injured cerebral microvasculature accepted the mitochondria transferred from the transplanted stem cells, thereby resulting in significantly improving in mitochondrial activity of injured microvasculature, enhancing angiogenesis, reducing infarct volume, and improving functional recovery. Our data provided the evidence that stem cells can rescue damaged cerebrovascular system in stroke through a mechanism not yet identified.


Asunto(s)
Encéfalo/irrigación sanguínea , Células Endoteliales/patología , Infarto de la Arteria Cerebral Media/cirugía , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Microvasos/patología , Mitocondrias/trasplante , Daño por Reperfusión/cirugía , Animales , Encéfalo/fisiopatología , Respiración de la Célula , Células Cultivadas , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Infarto de la Arteria Cerebral Media/fisiopatología , Células Madre Mesenquimatosas/metabolismo , Microvasos/metabolismo , Mitocondrias/metabolismo , Actividad Motora , Neovascularización Fisiológica , Ratas Sprague-Dawley , Recuperación de la Función , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Daño por Reperfusión/fisiopatología , Factores de Tiempo
9.
Phys Rev Lett ; 123(13): 137601, 2019 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-31697531

RESUMEN

In ferroelectric and relaxor-ferroelectric materials, piezoelectric and dielectric properties are significantly enhanced at the morphotropic phase boundary (MPB), a boundary between different ferroelectric phases with different macroscopic symmetries. By contrast, in relaxor systems, such an MPB does not exist because relaxors of different compositions possess the same macroscopic symmetry. Here, we report the existence of a morphotropic relaxor boundary (MRB) in the single phase relaxor region of a K_{0.5}Na_{0.5}NbO_{3}-xBaTiO_{3} system, which is a composition-induced boundary between two relaxors with different local polar symmetries (tetragonal versus rhombohedral) but with the same macroscopic cubic symmetry. At the MRB the electrostrain increases by ∼3 times and the permittivity increases by ∼1.5 times over a wide temperature range of more than 100 K, as compared with off-MRB compositions. Our Letter demonstrates that the MRB may become an effective mechanism to enhance the dielectric and electrostrictive properties of relaxors.

10.
J Anesth ; 32(1): 77-81, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29164334

RESUMEN

PURPOSE: Preoperative sleep study helps to predict post-adenotonsillectomy morphine requirements. However, in some institutions, many suspected children with obstructive sleep apnoea syndrome have an adenotonsillectomy without polysomnography assessments. This study investigated the relationship between the results of a fentanyl test performed before extubation and the postoperative morphine requirements in children after adenotonsillectomy. METHODS: Intravenous fentanyl (1 µg/kg) was given as a test before extubation when spontaneous ventilation was restored in 80 children aged 3-7 years who underwent adenotonsillectomy. The result was considered positive if the patient's respiratory rate decreased >50% after the test. In the recovery room, pain was assessed every 10 min using the Children's Hospital of Eastern Ontario Pain Scale. Rescue morphine (10 µg/kg) was given when the score was ≥6. RESULTS: The median [IQR (range)] cumulative morphine consumption rates for children with a positive result (n = 25) and a negative result (n = 52) were 30 (20, 40) and 50 (40, 50) µg/kg, respectively (P = 0.002). Eighty-eight percent of the positive-result patients and 48% of the negative-result patients were light consumers of morphine (cumulative dose <50 µg/kg) (P = 0.001). CONCLUSIONS: We conclude that children with a positive result after a fentanyl test require less morphine to achieve comfort than those with a negative result. CLINICALTRIALS. GOV ID: NCT02484222.


Asunto(s)
Adenoidectomía/métodos , Fentanilo/administración & dosificación , Morfina/administración & dosificación , Tonsilectomía/métodos , Extubación Traqueal , Niño , Preescolar , Femenino , Humanos , Masculino , Dimensión del Dolor , Polisomnografía , Periodo Posoperatorio , Apnea Obstructiva del Sueño/complicaciones
11.
J Pediatr Gastroenterol Nutr ; 60(1): 84-90, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25238119

RESUMEN

OBJECTIVE: Biliary atresia (BA) is a devastating liver disease in infants. Progressive hepatic fibrosis is often observed in postoperative patients with BA even after a successful Kasai portoenterostomy procedure. MicroRNA-222 (miRNA) has been linked to the activation of stellate cells and the progression of liver fibrosis. METHODS: In this study, the miR-222 expression profile in BA and infants with anicteric choledochal cyst (CC) was determined. The functional effect of miR-222 inhibition on the growth of the human hepatic stellate cell line LX-2 was also evaluated. The downstream signaling pathways and target of miR-222 were determined by coupling gene expression profiling and pathway analysis and by in silico prediction, respectively. In addition, we demonstrated miR-222 overexpression in patients with BA compared with choledochal cyst controls. RESULTS: Inhibition of miR-222 in the LX-2 cell line significantly decreased cell proliferation. We also identified protein phosphatase 2A subunit B as a target of miR-222. The downstream signaling pathway, Akt, was also influenced by miR-222. A consistent reduction of Akt phosphorylation and Ki67 in the LX-2 line was shown following miR-222 suppression. CONCLUSIONS: Our results show that miR-222 overexpression is common in BA and contributes to LX-2 cell proliferation by targeting protein phosphatase 2A subunit B and Akt signaling.


Asunto(s)
Atresia Biliar/fisiopatología , Cirrosis Hepática/etiología , Hígado/metabolismo , MicroARNs/metabolismo , Modelos Biológicos , Proteína Fosfatasa 2/antagonistas & inhibidores , Regulación hacia Arriba , Atresia Biliar/metabolismo , Atresia Biliar/patología , Atresia Biliar/cirugía , Línea Celular , Proliferación Celular , Progresión de la Enfermedad , Femenino , Células Estrelladas Hepáticas/citología , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Humanos , Lactante , Hígado/patología , Cirrosis Hepática/fisiopatología , Masculino , Portoenterostomía Hepática , Estudios Prospectivos , Proteína Fosfatasa 2/genética , Proteína Fosfatasa 2/metabolismo , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Interferencia de ARN , Transducción de Señal
12.
Sleep Med ; 115: 39-47, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38330694

RESUMEN

OBJECTIVE: Insomnia is a common sleep disorder, often associated with some mental disorders or mental health concerns, especially when accompanied by depression or anxiety, but very limited research has been reported in China. The purpose of this study was to investigate the prevalence of insomnia and associations with depression, anxiety in Chinese adults. METHODS: We conducted this large-sample cross-sectional study (51774 adults) in Guangdong province from October to December 2022. We used multistage stratified equal-volume random sampling under a complex sampling design to select the sample and standardized structured questionnaires to collect the necessary information. Descriptive analysis and logistic regression model were used for statistical analysis. RESULTS: The weighted prevalence of insomnia was 24.8 %. Insomnia was significantly associated with depression (OR:11.29, 95 %CI: 9.58-13.29), and anxiety (OR:10.98, 95 %CI: 8.78-13.72). Risk factors as being associated with insomnia were female, higher years of education, suffering from chronic diseases, previous drinking and current drinking, while protective factors were living in a rural area, married or cohabited, divorce or separation and being older. Risk factors as being associated with depression in the insomnia group included 10-16 years of education and suffering from chronic diseases, while protective factors were being older, married or cohabited, and normal BMI. Risk factors associated with anxiety in the insomnia group included 7-12 years of education and suffering from chronic diseases, while protective factors were being older, married or cohabited, and having a normal BMI. CONCLUSIONS: Insomnia is associated with the development of depression and anxiety. Women and unhealthy lifestyle were at high risk for insomnia, had chronic diseases is an important factor, and insomnia with depression or anxiety.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Adulto , Humanos , Femenino , Masculino , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Estudios Transversales , Depresión/epidemiología , Depresión/psicología , Prevalencia , Ansiedad/epidemiología , Ansiedad/psicología , Enfermedad Crónica , China/epidemiología
13.
Microbes Infect ; : 105304, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38278475

RESUMEN

As the high pathogenic species of Filoviridae virus family, Orthoebolavirus zairense (EBOV) shows frequent outbreaks in human in recently years since its first emerging in 1976 in Democratic Republic of the Congo (COD), bringing ongoing risks and burden on public health safety. Here, the phylogenetic relationship among major outbreaks was analyzed. The results showed that EBOV isolates could be divided into four lineages according to spatial and temporal epidemics. Then, the positive selection sites (PSSs) were detected on all proteins of the EBOV, exhibiting lineage characteristic. Particularly, sites in GP and VP24 were identified to be significantly under positive selection, and partial of which were maintained in the latest isolates in 2021. GP and L were found to have high variability between lineages. Substitutions including F443L and F443S in GP, as well as F1610L and I1951V in L could be characteristic of the two large outbreaks in COD (2018) and West Africa (2014), respectively. Further, substitutions of significant PSSs in VP24 and L proteins were visualized for analysis of structural changes, which may affect EBOV pathogenesis. In summary, our results gains insights in genetic characteristic and adaptive evolution of EBOV, which could facilitate gene functional research against EBOV.

14.
Paediatr Anaesth ; 23(4): 322-7, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23072260

RESUMEN

BACKGROUND: Acceleromyography used to monitor the neuromuscular transmission function is available in infants and children. However, information on the so-called staircase phenomenon during the baseline stabilization period in this population is limited. Our objective was to assess the characteristics of such phenomenon in infants in acceleromyography. METHODS: Thirty infants were divided into three groups: group A (aged 1-5 months, n = 10), group B (aged 6-11 months, n = 10), and group C (aged 12-24 months, n = 10). Anesthesia was induced and maintained without neuromuscular blocking agents. Patients received a supramaximal stimulus followed by TOF measurements every 15 s over the course of 30 min with a TOF-Watch(®) SX. All data were collected in a notebook computer using the TOF-Watch(®) SX Monitor software through optical fibers. RESULTS: The evoked T1 responses in younger infants (group A) were significantly lower than those in older infants (groups B and C) from 0-20 min. In group A, the signals increased to the maximum value of 121 ± 15% that of the control at 7.25 min and decreased toward a plateau of 113 ± 18% at 30 min. In group B, the signal heights increased to the maximum value of 143 ± 14% at 9.5 min, then decreased slowly to 136 ± 10% at 19.5 min, finally reaching 116 ± 12% at 30 min. In group C, the mean values of T1 reached the maximum of 139 ± 19% that of control at 9.5 min and finally reached 126 ± 22% of control at 30 min. CONCLUSIONS: The staircase effect presents in a shorter time course and at lower degrees in smaller infants. However, in older infants, staircase effect still presents in a long period and may influence the onset time and duration of twitch depression after muscle relaxants administration.


Asunto(s)
Anestesia , Monitoreo Intraoperatorio/estadística & datos numéricos , Miografía/métodos , Análisis de Varianza , Anestesia General , Anestesia por Inhalación , Anestesia Intravenosa , Anestésicos por Inhalación , Anestésicos Intravenosos , Peso Corporal/fisiología , Estimulación Eléctrica , Femenino , Humanos , Lactante , Masculino , Monitoreo Intraoperatorio/métodos , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiología , Óxido Nitroso , Piperidinas , Propofol , Remifentanilo , Transmisión Sináptica/efectos de los fármacos
15.
Sensors (Basel) ; 13(9): 11539-52, 2013 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-24002230

RESUMEN

Based on the core hysteresis features, the RTD-fluxgate core, while working, is repeatedly saturated with excitation field. When the fluxgate simulates, the accurate characteristic model of the core may provide a precise simulation result. As the shape of the ideal hysteresis loop model is fixed, it cannot accurately reflect the actual dynamic changing rules of the hysteresis loop. In order to improve the fluxgate simulation accuracy, a dynamic hysteresis loop model containing the parameters which have actual physical meanings is proposed based on the changing rule of the permeability parameter when the fluxgate is working. Compared with the ideal hysteresis loop model, this model has considered the dynamic features of the hysteresis loop, which makes the simulation results closer to the actual output. In addition, other hysteresis loops of different magnetic materials can be explained utilizing the described model for an example of amorphous magnetic material in this manuscript. The model has been validated by the output response comparison between experiment results and fitting results using the model.


Asunto(s)
Campos Magnéticos , Magnetismo/instrumentación , Magnetismo/métodos , Modelos Teóricos , Dinámicas no Lineales , Simulación por Computador
16.
Carbohydr Polym ; 313: 120868, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37182959

RESUMEN

Soft actuators and sensors have attracted extensive scientific interest attributed to their great potential applications in various fields, but the integration of actuating and sensing functions in one material is still a big challenge. Here, we developed an electrospun cellulose acetate (CA)/carbon nanotube nanofiborous composite with both functional applications as multi-responsive shape memory actuators and triboelectric nanogenerator (TENG) based sensors. Attributed to excellent thermo- and light-induced shape memory performance, the CA nanofiborous composites showed high heavy-lift capability as light driven actuators, able to lift burdens 1050 times heavier than their own weight. The CA nanofiborous membranes based TENG exhibited high output performance with open-circuit voltage, short-circuit density, and instantaneous power density about 103.2 V, 7.93 mA m-2 and 0.74 W m-2, respectively. The fabricated TENG based pressure sensor exhibited a high sensitivity of 3.03 V kPa-1 below 6.8 kPa and 0.11 V kPa-1 in the pressure range from 6.8 to 65 kPa, which can be effectively used to monitor human motion state and measure wind velocity. It is expected that the electrospun composites with actuating and sensing functions will show prosperous applications prospects in soft robotics.

17.
Microbiol Spectr ; 11(4): e0081023, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37265414

RESUMEN

The Yangtze finless porpoise (YFP) (Neophocaena asiaeorientalis asiaeorientalis) is a critically endangered freshwater cetacean, with about 1,249 individuals thought to be left in the wild. However, viral entities and viral diseases of YFPs remain obscure. In this study, anal swabs for virome analysis were collected during the physical examination of YFPs in the Tian-E-Zhou Oxbow (TEO) ex situ reserve. A total of 19 eukaryotic viral species belonging to 9 families, including Papillomaviridae, Herpesviridae, Picornaviridae, Picobirnaviridae, Caliciviridae, Retroviridae, Parvoviridae, Virgaviridae, and Narnaviridae, and other unclassified viruses were identified based on metasequencing. Among these detected viruses, a novel herpesvirus (NaHV), two different kobuviruses (NaKV1-2), and six different papillomaviruses (NaPV1 to -6) were considered potential risks to YFPs and confirmed by PCR or reverse transcription-PCR (RT-PCR). Most YFPs sampled were found to harbor one or more kinds of detected viral genomes (52/58 [89.7%]). Surveillance results demonstrated that kobuvirus and herpesvirus displayed obvious age distribution and PVs showed significant gender difference in YFPs. According to species demarcation criteria in individual genera in Papillomaviridae, two novel species (referred to as Omikronpapillomavirus 2 and 3) and four novel isolates of PV were identified in YFPs. Further evolutionary analysis suggested that NaPVs would occupy the mucosal niche and that virus-host codivergence mixed with duplications and host-switching events drives the evolution of cetacean PVs. Divergence times of PVs in YFP and other cetacean reflect the incipient speciation of YFPs. In summary, our findings revealed the potential viral entities, their prevalence, and their evolutionary history in YFPs, which raises an important issue regarding effects of viral infection on the fitness of YFPs. IMPORTANCE The Yangtze finless porpoise (YFP) is the only cetacean species in freshwater following the functional extinction of the baiji (Lipotes vexillifer). Health management, disease treatment, and other special measures are important for maintaining the existing YFP populations, especially in in situ and ex situ reserves. The discovery of potential viral entities and their prevalence in YFPs raises an important issue regarding the effects of viral infection on the fitness of YFPs and may contribute to the conservation of YFPs. The evolutionary history of papillomaviruses in YFP and other cetaceans reflects the phylogeny of their hosts and supports the status of incipient species, opening a window to investigate the evolutionary adaptation of cetaceans to freshwater as well as their phylogeny to remedy the deficiency of fossil evidence.


Asunto(s)
Marsopas , Animales , Agua Dulce , Células Eucariotas
18.
Ann Hematol ; 91(4): 553-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21987025

RESUMEN

MicroRNAs (miRNAs) are regulatory RNA molecules that are deregulated in many disease types, including cancer. Recently, miRNAs have shown promise as markers for cancer diagnosis. The aim of this study was to investigate whether serum miRNAs can be used as biomarkers for the detection of diffuse large B cell lymphoma (DLBCL). We measured the levels of miRNAs (miR-15a, miR-16-1, miR-21, miR-29c, miR-34a, miR-155, and miR-223) in serum samples from patients with DLBCL and healthy controls using real-time quantitative reverse-transcription polymerase chain reaction (qRT-PCR). We show here that miRNAs are present in human serum in a remarkably stable form. Four of miRNAs (miR-15a, miR-16-1, miR-29c, and miR-155) were significantly elevated in DLBCL serum when compared with normal controls (P < 0.05), while miR-34a was downregulated in DLBCL serum when compared with controls (P < 0.05). Receiver operating characteristic analyses reflects strong discriminating DLBCL from controls, with area under the curves of 0.7722, 0.7002, 0.6672, 0.8538, and 0.7157 for miR-15a, miR-16-1, miR-29c, miR-34a, and miR-155, respectively. At the cut-off value of 0.0006 for miR-15a, the sensitivity was 80% and the specificity was 76%; at the cut-off value of 0.0886 for miR-16-1, the sensitivity was 94% and the specificity was 51%; at the cut-off value of 1.395 for miR-34a, the sensitivity was 100% and the specificity was 70%; at the cut-off value of 0.0022 for miR-155, the sensitivity was 83% and the specificity was 65%. In conclusion, these data suggest that serum miRNAs are potentially useful tools as novel noninvasive biomarker for the diagnosis of DLBCL.


Asunto(s)
Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/genética , Linfoma de Células B Grandes Difuso/sangre , Linfoma de Células B Grandes Difuso/genética , MicroARNs/sangre , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Linfoma de Células B Grandes Difuso/patología , Masculino , MicroARNs/genética , Persona de Mediana Edad , Curva ROC , Adulto Joven
19.
Materials (Basel) ; 15(22)2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36431386

RESUMEN

The amorphous phase and strain glass are both disordered states of solids. The amorphous phase is an atomic packing disordered phase, while strain glass is a glassy state with transformation strain disorder in a crystalline matrix, which both bring extraordinary properties to alloys. Previous studies have mostly focused on the properties and structure of single glass; however, the link between them has seldom been considered. In this work, the specimen of the almost amorphous state was obtained from the heavy-defects-doping Fe67.8Pd32.2 strain glass ingot by arc melting and 90% cold rolling, which were characterized by amorphous packages in X-ray diffraction and amorphous rings in transmission electron microscope diffraction. The evolution from the amorphous phase (metallic glass) back to strain glass was directly observed by an in situ high-resolution transmission electron microscope, which revealed that strain nanodomains began to form on the amorphous matrix below the crystallization temperature of the amorphous phase. Here, direct observation of the evolution process provides a theoretical basis for achieving precise control of crystallinity to obtain the desired microstructure, while the study of the unusual crystallization process offers a possible way to tailor the mechanical and functional properties through tuning the amorphous and strain glass coexistence. This work presents the specific pathway and realization possibilities for the design of glass composite materials with enhanced properties.

20.
Sci Rep ; 12(1): 305, 2022 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-35013401

RESUMEN

Suicide is increasingly recognized as a major public health concern among migrant workers in China. Despite negative mental and negative coping styles being core themes found in suicide notes, there is scarce research addressing the theoretical framework of underlying mechanisms between these variables. The study was designed to examine the relationships of negative mental, negative coping styles, and suicide risk among migrant workers. It hypothesized that negative mental would exert a positive effect on suicide risk via increased negative coping. Using a cross-sectional design, the study was conducted using a sample of 3095 migrant workers from Shenzhen, China. Self-made Suicide Risk Scale (SRS), Short-form of the ULCA Loneliness Scale (USL-6), Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Scale (GAD-7), Simplified Coping Style Questionnaire (SCSQ) were used to collect data. Structural equation modeling (SEM) was performed to quantitatively explore the path effects between negative mental, negative coping styles and suicide risk. Results showed that negative coping style had a positive association with suicide risk (ß = 0.029, P < 0.001). Negative mental had both direct and indirect positive effects on suicide risk through negative coping styles (ß = 0.109, ß = 0.013, P < 0.001). Therefore, to prevent suicidal behaviors among migrant workers, targeted interventions focusing on improving their mental health and coping strategies are needed.


Asunto(s)
Adaptación Psicológica , Salud Mental , Salud Laboral , Ideación Suicida , Suicidio/psicología , Migrantes/psicología , Adulto , Ansiedad/epidemiología , Ansiedad/psicología , China/epidemiología , Estudios Transversales , Depresión/epidemiología , Depresión/psicología , Femenino , Humanos , Soledad/psicología , Masculino , Persona de Mediana Edad , Medición de Riesgo , Factores de Riesgo , Encuestas y Cuestionarios , Prevención del Suicidio
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