RESUMO
This study investigates the distribution of rare earth elements (REEs) within the Beijing water system, specifically examining the Yongding, Chaobai, Beiyun, Jiyun, and Daqing rivers. Results indicate that the Beiyun River exhibits the highest REE concentrations, ranging from 35.95 to 59.78 µg/mL, while the Daqing River shows the lowest concentrations, ranging from 15.79 to 17.48 µg/mL. LREEs (La to Nd) predominate with a total concentration of 23.501 µg/mL, leading to a notable LREE/HREE ratio of 7.901. Positive Ce anomalies (0.70-1.11) and strong positive Eu anomalies (1.38-2.49) were observed. The study suggests that the Beijing water system's REEs may originate from geological and anthropogenic sources, such as mining and industrial activities in neighboring regions, including Inner Mongolia. These findings underscore the importance of ongoing monitoring and effective water management strategies to address REE-related environmental concerns.
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Monitoramento Ambiental , Metais Terras Raras , Rios , Poluentes Químicos da Água , Metais Terras Raras/análise , Monitoramento Ambiental/métodos , Rios/química , Poluentes Químicos da Água/análise , Pequim , China , Fracionamento QuímicoRESUMO
Surface ozone is a severe air pollution problem in the North China Plain, which is home to 300 million people. Ozone concentrations are highest in summer, driven by fast photochemical production of hydrogen oxide radicals (HOx) that can overcome the radical titration caused by high emissions of nitrogen oxides (NOx) from fuel combustion. Ozone has been very low during winter haze (particulate) pollution episodes. However, the abrupt decrease of NOx emissions following the COVID-19 lockdown in January 2020 reveals a switch to fast ozone production during winter haze episodes with maximum daily 8-h average (MDA8) ozone concentrations of 60 to 70 parts per billion. We reproduce this switch with the GEOS-Chem model, where the fast production of ozone is driven by HOx radicals from photolysis of formaldehyde, overcoming radical titration from the decreased NOx emissions. Formaldehyde is produced by oxidation of reactive volatile organic compounds (VOCs), which have very high emissions in the North China Plain. This remarkable switch to an ozone-producing regime in January-February following the lockdown illustrates a more general tendency from 2013 to 2019 of increasing winter-spring ozone in the North China Plain and increasing association of high ozone with winter haze events, as pollution control efforts have targeted NOx emissions (30% decrease) while VOC emissions have remained constant. Decreasing VOC emissions would avoid further spreading of severe ozone pollution events into the winter-spring season.
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Poluição do Ar/análise , Ozônio/análise , Material Particulado/análise , Estações do Ano , Compostos Orgânicos Voláteis , COVID-19 , China , Produtos Agrícolas , Monitoramento Ambiental , Poluição Ambiental , Humanos , Óxidos de Nitrogênio/química , Pandemias , Saúde PúblicaRESUMO
Objective: To explore whether contrast-enhanced ultrasound (CEUS) can improve tubal ectopic pregnancy detection rate, tubal dilation, tubal hematoma, and gestational sac. Methods: This retrospective study included 34 patients with suspected ectopic pregnancy who underwent contrast-enhanced ultrasound at Dongzhimen Hospital of Beijing University of Chinese Medicine between March 2021 and September 2016. Of these, 27 patients were confirmed to have tubal pregnancy by laparoscopic surgery and histopathology. Four ultrasound physicians (2 experts and 2 non-experts) conducted a retrospective analysis of conventional color Doppler ultrasound and the combination of conventional color Doppler ultrasound with contrast-enhanced ultrasound (color Doppler ultrasound + CEUS). They analyzed the differences in confidence levels and reproducibility in identifying tubal dilation, tubal hematoma, and gestational sac implantation sites. Additionally, the characteristic features of ectopic pregnancy on contrast-enhanced ultrasound were summarized, including gestational sac morphology, triple ring sign, enhancement patterns (branching or punctate), tubal dilation (with or without hematoma), contrast enhancement of tubal walls, and presence of free fluid. Results: In the expert group, the correct identification rate of the gestational sac implantation site on ultrasound images increased from 13/34 (38.2%) with conventional color Doppler ultrasound to 20/34 (58.8%) with color Doppler ultrasound + CEUS, the differences were statistically significant (38.2% vs. 58.8%, P = .039). The correct identification rate of tubal dilation increased from 6/34 (17.7%) to 25/34 (73.5%) (P = .001), and the correct identification rate of tubal hematoma increased from 3/34 (8.8%) to 17/34 (50.0%) with color Doppler ultrasound + CEUS (P < .001). In the non-expert group, the correct identification rate of the gestational sac implantation site increased from 8/24 (23.5%) with conventional ultrasound to 19/34 (55.9%) with ultrasound + CEUS (P = .003). The correct identification rate of tubal dilation increased from 6/34 (17.7%) to 23/34 (67.7%) (P < .001), and the correct identification rate of tubal hematoma increased from 3/34 (8.82%) to 12/34 (35.3%) with color Doppler ultrasound + CEUS (P = .012). Conclusion: The analysis of contrast-enhanced ultrasound images provides characteristic features and diagnostic points for tubal ectopic pregnancy, including gestational sac, thick ring sign, tubal dilation, and tubal dilation with hematoma. This approach improves the accuracy of partial pregnancy of unknown location (PUL) diagnosis and reduces the technical dependence on ultrasound personnel.
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Gravidez Ectópica , Gravidez Tubária , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Gravidez Tubária/diagnóstico por imagem , Gravidez Ectópica/diagnóstico por imagem , Resultado do Tratamento , HematomaRESUMO
Jingmen tick virus (JMTV) is a novel tick-borne virus first identified from Jingmen city, Hubei Province of China in 2010. It has been proved that JMTV can cause human diseases and is widely distributed both inside and outside of China. However, the survival mode and transmission characteristics of JMTV still need further research, particularly in terms of transovarial transmission. In this study, an investigation was conducted to explore the presence of JMTV from engorged female ticks to their offspring. All engorged female adult ticks were collected from domestic cattle and allowed to lay eggs in appropriate humidity and temperature conditions. Maternal ticks, eggs and larvae were screened for JMTV RNA through real-time polymerase chain reaction (RT-PCR) and nested PCR methods. The results revealed the positive rate of 10.53% (10/95) in engorged ticks, 9.09% (2/22) in eggs and 8% (4/50) in larvae pools, respectively. Phylogenetic analysis confirmed that sequences from eggs and larvae had closer relationship with those isolates from maternal engorged ticks with more than 99.7% homology and JMTV manifested with evolutional conservatism. Our study has identified for the first time that JMTV could be transmitted from mother generation to offspring of Haemaphysalis Longicornis. Nonetheless, the efficiency of transovarial transmission in JMTV and the significance of ticks as amplification hosts still need to be further illustrated.
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Ixodidae , Carrapatos , Vírus , Animais , Bovinos , Feminino , Humanos , Filogenia , ChinaRESUMO
Pyriproxyfen is a juvenile hormone-like pesticide. Once intake occurs, it leads to a series of poisoning characters consequences in silkworm, Bombyx mori (ID: 7091, Lepidoptera), such as non- cocooning, non-pupation, production of low-active eggs, and extended stages. However, the poisoning mechanism is still unclear. Here, silkworms were fed mulberry leaves soaked with different pyriproxyfen concentrations, and the heads were dissected for transcriptome analysis, while the hemolymph was used for determinations of ecdysone and juvenile hormone titers. As a result, after conjoint analysis of 3 feeding groups and a control group, 555 differentially expressed genes (DEGs) were obtained, which were mainly involved in hormone metabolism, glycometabolism and protein metabolism. Meanwhile, 119 genes were significantly correlated with the pyriproxyfen concentrations, and they were mainly involved in drug metabolism and glycometabolism. The ecdysone titers in several feeding groups were significantly lower than those of the control group, while juvenile hormone was not detected in all groups, including the control and feeding groups. Correspondingly, due to activation of the juvenile hormone signaling pathway by pyriproxyfen, key genes in the ecdysone synthesis pathway were downregulated, and a large number of downstream genes were up- or downregulated. In addition, nearly all genes in the detoxification pathway were upregulated. These results suggested that, affected by the juvenile hormone signaling pathway, ecdysone titers decreased and further affected a series of downstream processes, and this was the key reason for pyriproxyfen poisoning in silkworm, B. mori, which could lay a foundation for the study of pyriproxyfen resistance in silkworm.
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Bombyx , Animais , Bombyx/genética , Bombyx/metabolismo , Ecdisona/metabolismo , Piridinas/farmacologia , Hormônios Juvenis/farmacologia , Hormônios Juvenis/metabolismo , Transdução de SinaisRESUMO
Organ-on-A-chip (OoAC) devices are miniaturized, functional, in vitro constructs that aim to recapitulate the in vivo physiology of an organ using different cell types and extracellular matrix, while maintaining the chemical and mechanical properties of the surrounding microenvironments. From an end-point perspective, the success of a microfluidic OoAC relies mainly on the type of biomaterial and the fabrication strategy employed. Certain biomaterials, such as PDMS (polydimethylsiloxane), are preferred over others due to their ease of fabrication and proven success in modelling complex organ systems. However, the inherent nature of human microtissues to respond differently to surrounding stimulations has led to the combination of biomaterials ranging from simple PDMS chips to 3D-printed polymers coated with natural and synthetic materials, including hydrogels. In addition, recent advances in 3D printing and bioprinting techniques have led to the powerful combination of utilizing these materials to develop microfluidic OoAC devices. In this narrative review, we evaluate the different materials used to fabricate microfluidic OoAC devices while outlining their pros and cons in different organ systems. A note on combining the advances made in additive manufacturing (AM) techniques for the microfabrication of these complex systems is also discussed.
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Materiais Biocompatíveis , Microfluídica , Humanos , Microfluídica/métodos , Materiais Biocompatíveis/química , Sistemas Microfisiológicos , Hidrogéis/química , Microtecnologia , Impressão TridimensionalRESUMO
White matter maturation has been characterized by diffusion tensor (DT) metrics. However, maturational processes and degrees are not fully investigated due to limitations of univariate approaches and limited specificity/sensitivity. Diffusion kurtosis imaging (DKI) provides kurtosis tensor (KT) and white matter tract integrity (WMTI) metrics, besides DT metrics. Therefore, we tried to investigate performances of DKI with the multiparametric analysis in characterizing white matter maturation. Developmental changes in metrics were investigated by using tract-based spatial statistics and the region of interest analysis on 50 neonates with postmenstrual age (PMA) from 37.43 to 43.57 weeks. Changes in metrics were combined into various patterns to reveal different maturational processes. Mahalanobis distance based on DT metrics (DM,DT ) and that combing DT and KT metrics (DM,DT-KT ) were computed, separately. Performances of DM,DT-KT and DM,DT were compared in revealing correlations with PMA and the neurobehavioral score. Compared with DT metrics, WMTI metrics demonstrated additional changing patterns. Furthermore, variations of DM,DT-KT across regions were in agreement with the maturational sequence. Additionally, DM,DT-KT demonstrated stronger negative correlations with PMA and the neurobehavioral score in more regions than DM,DT . Results suggest that DKI with the multiparametric analysis benefits the understanding of white matter maturational processes and degrees on neonates.
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Desenvolvimento Infantil/fisiologia , Imagem de Difusão por Ressonância Magnética/métodos , Neuroimagem/métodos , Substância Branca/diagnóstico por imagem , Substância Branca/crescimento & desenvolvimento , Feminino , Humanos , Recém-Nascido , MasculinoRESUMO
Carrageenan is a highly potent anti-human papillomavirus (HPV) agent with the potential for formulation as a mouthwash against oral HPV infection. However, its toxic effect on tissues of the oral cavity is currently unknown. This study aims to evaluate the safety of carrageenan on human cells and tissues of the oral cavity. Human salivary gland cells and reconstructed human oral epithelium (RHOE) were used for this in vitro study. The cells were subjected to 0.005-100 µg/mL of carrageenan for 4, 12, and 24 h in quadruplicate. RHOE were exposed to 100 µg/mL of carrageenan for 24 h in triplicate and stained with hematoxylin/eosin for histological analyses. All experiments had saline and 1% sodium dodecyl sulphate (SDS) as negative and positive controls, respectively. Carrageenan tissue toxicity was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to quantify cell viability. Tissue toxicity was further evaluated histologically by an oral pathologist to assess morphological changes. Our data showed that carrageenan did not significantly decrease cell and tissue viability when compared to the positive control. The histological evaluation of the RHOE also showed no loss of viability of the carrageenan-treated sample compared to untreated tissue. In contrast, 1% SDS-treated RHOE showed extensive tissue destruction. Our experiments suggest that carrageenan is safe for use in the oral cavity.
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Infecções por Papillomavirus , Carragenina , Sobrevivência Celular , Humanos , Boca , Antissépticos Bucais/toxicidadeRESUMO
The Yao silkworm is a unique silkworm resource producing yellow flat plate silk that has only been reared by the Baiku Yao ethnic group in Nandan County, Guangxi Province, China for a thousand years. Here, we report the mitochondrial genomes (mitogenomes) of five Yao silkworm strains and 10 local Guangxi strains of the domestic silkworm (Bombyx mori) L. (Lepidoptera: Bombycidae), and use the resulting mitogenomes and the available Bombyx mitogenomes to characterize their genome architecture and trace the evolutionary origin of the Yao silkworm. The five Yao silkworm mitogenomes exhibited genome architectures identical to typical set of 37 mitochondrial genes (13 protein-coding genes, 22 transfer RNAs, and two ribosomal RNAs) and a high level of genome sequence similarity with the domestic silkworm. Mitogenome-based phylogenetic reconstruction provided solid evidence that the Yao silkworm shares a common ancestor with the domestic silkworm. Sliding window analysis uncovered a distinct variation pattern in the mitogenome between the Yao silkworm and the other domestic silkworm strains. The phylogenetic analyses revealed a basal placement of the Yao silkworm among all available domestic silkworm strains, indicating that the Yao silkworm is an ancient population of the domestic silkworm. Our data indicated that the Yao silkworm (B. mori) is a lineage of the domestic silkworm, which for the first time provides insights into the origin of the Yao silkworm.
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Bombyx , Genoma Mitocondrial , Lepidópteros , Animais , Bombyx/genética , China , Fósseis , FilogeniaRESUMO
BACKGROUND AND AIMS: Observational studies have suggested that plasma lipids contribute substantially to cardiovascular disease, but "cholesterol paradox" in atrial fibrillation (AF) remains. We sought to investigate the causal effects of lipid profiles on the risk of AF. METHODS AND RESULTS: Two-sample Mendelian randomization (MR) framework was implemented to examine the causality of association. Summary estimations of genetic variants associated with low density lipoprotein (LDL)-cholesterol, high density lipoprotein (HDL)-cholesterol, total cholesterol, triglycerides, lipoprotein-a [Lp(a)], apolipoprotein A1 (ApoA 1), and apolipoprotein B (ApoB) were 81, 99, 96, 61, 30, 10, and 23 single nucleotide polymorphisms, respectively. Genetic association with AF were retrieved from a genome-wide association study that included 1,030,836 individuals. The complications for AF were predefined as cardioembolic stroke (CES) and heart failure (HF). In the multivariable MR, the odds ratios for AF per standard deviation (SD) increase were 1.030 (95% confidence interval (CI) 0.979-1.083; P = 0.257) for LDL-cholesterol, 0.986 (95% CI 0.931-1.044; P = 0.622) for HDL-cholesterol, 0.965 (95% CI 0.896-1.041; P = 0.359) for triglycerides, 1.001 (95% CI 1.000-1.003; P = 0.023) for Lp(a), 1.017 (95% CI 0.966-1.070; P = 0.518) for ApoA1, and 1.002 (95% CI 0.963-1.043; P = 0.923) for ApoB. There was no evidence that other lipid components were causally associated with AF, CES, or HF, other than for a marginal association between triglycerides and HF. CONCLUSIONS: This MR study provides robust evidence that high Lp(a) increases the risk of AF, suggesting that interventions targeting Lp(a) may contribute to the primary prevention of AF.
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Fibrilação Atrial/sangue , Fibrilação Atrial/genética , Lipoproteína(a)/sangue , Lipoproteína(a)/genética , Polimorfismo de Nucleotídeo Único , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Biomarcadores/sangue , Estudos de Casos e Controles , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Análise da Randomização Mendeliana , Análise Multivariada , Fenótipo , Prognóstico , Medição de Risco , Fatores de Risco , Regulação para CimaRESUMO
Sox proteins are known as crucial transcription factors for many developmental processes and for a wide range of common diseases. They were believed to specifically bind and bend DNA with other transcription factors and elicit transcriptional activation or repression activities in the early stage of transcription. However, their functions are not limited to transcription initiation. It has been showed that Sox proteins are involved in the regulation of alternative splicing regulatory networks and translational control. In this review, we discuss the current knowledge on how Sox transcription factors such as Sox2, Sry, Sox6, and Sox9 allow the coordination of co-transcriptional splicing and also the mechanism of SOX4-mediated translational control in the context of RNA polymerase III.
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Fatores de Transcrição SOX , Processamento Alternativo , Animais , Humanos , Biossíntese de Proteínas , RNA Polimerase III , Splicing de RNA , Fatores de Transcrição SOX/genética , Fatores de Transcrição SOX/fisiologia , Spliceossomos/metabolismo , Ativação TranscricionalRESUMO
Tissue engineering has been an inveterate area in the field of regenerative medicine for several decades. However, there remains limitations to engineer and regenerate tissues. Targeted therapies using cell-encapsulated hydrogels, such as mesenchymal stem cells (MSCs), are capable of reducing inflammation and increasing the regenerative potential in several tissues. In addition, the use of MSC-derived nano-scale secretions (i.e., exosomes) has been promising. Exosomes originate from the multivesicular division of cells and have high therapeutic potential, yet neither self-replicate nor cause auto-immune reactions to the host. To maintain their biological activity and allow a controlled release, these paracrine factors can be encapsulated in biomaterials. Among the different types of biomaterials in which exosome infusion is exploited, hydrogels have proven to be the most user-friendly, economical, and accessible material. In this paper, we highlight the importance of MSCs and MSC-derived exosomes in tissue engineering and the different biomaterial strategies used in fabricating exosome-based biomaterials, to facilitate hard and soft tissue engineering.
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Exossomos/metabolismo , Hidrogéis , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Engenharia Tecidual , Animais , Materiais Biocompatíveis/química , Diferenciação Celular , Portadores de Fármacos , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Humanos , Hidrogéis/química , Osteogênese , Medicina RegenerativaRESUMO
BACKGROUND: Industrial Fuling Zhacai is pickled by a method summarized as 'three times pickled and pressed', in which raw mustard tubers are subjected to three stages of pickling in different salt concentrations, with a pressing operation at the end of each stage to remove brine. This study used Illumina MiSeq technology and multivariate statistical analyses to investigate microbial community succession during the pickling process and its correlation with Zhacai biochemical indices. RESULTS: A total of 19 phyla, 208 genera, and 295 species of bacteria were identified. Lactobacillus was the dominant genus of bacteria in all three stages and Lactobacillus sakei was the dominant species in the first and second stages. A total of six phyla, 200 genera and 301 species of fungi were also identified. According to a PICRUSt2 prediction, the main functions of the bacterial and fungal communities were carbohydrate and protein metabolism, while alcohol metabolism was also a function of fungi. Nine bacterial genera closely correlated with Zhacai biochemical indices: Acinetobacter, Pseudomonas, Pedobacter, Erwinia, Lactobacillus, Chryseobacterium, Flavobacterium, Duganella, and Paenarthrobacter. Six genera of fungi correlated closely: Penicillium, Cystobasidium, Cladosporium, Plenodomus, Aspergillus, and Simplicillium. All these genera probably originated from the surface microorganisms of raw mustard tuber. CONCLUSION: This study reveals the succession patterns of microbial community structures during the pickling process of industrial Zhacai and infers the core functional flora, providing reference data for Zhacai pickling process control. © 2020 Society of Chemical Industry.
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Bactérias/isolamento & purificação , Alimentos Fermentados/microbiologia , Fungos/isolamento & purificação , Microbiota , Mostardeira/microbiologia , Bactérias/classificação , Bactérias/genética , Fermentação , Fungos/classificação , Fungos/genética , MetagenômicaRESUMO
OBJECTIVE: To explore the genetic basis for a patient with clinically suspected neurofibromatosis type I, alopecia areata and vitiligo. METHODS: Variant of the NF1 gene was detected by chip capture and high-throughput sequencing. Candidate variant was verified by Sanger sequencing of the family trio. RESULTS: The patient was found to harbor a novel missense c.1885G>A (p.Gly629Arg) variant of the NF1 gene, for which neither parent was carrier. The variant was not recorded in the public database. Based on the guidelines for genetic variation of the American College of Medical Genetics and Genomics, the c.1885G>A missense variant was predicted to be pathogenic (PS1+PS2+PM2+PP3+PP4). CONCLUSION: The c.1885G>A missense variant probably underlay the disease in this child. Above finding has enriched the spectrum of the NF1 gene variants.
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Alopecia em Áreas , Neurofibromatose 1 , Vitiligo , Alopecia em Áreas/genética , Criança , Genômica , Humanos , Mutação , Neurofibromatose 1/genética , Vitiligo/genéticaRESUMO
Hydrogels have been used for a variety of biomedical applications; in tissue engineering, they are commonly used as scaffolds to cultivate cells in a three-dimensional (3D) environment allowing the formation of organoids or cellular spheroids. Egg white-alginate (EWA) is a novel hydrogel which combines the advantages of both egg white and alginate; the egg white material provides extracellular matrix (ECM)-like proteins that can mimic the ECM microenvironment, while alginate can be tuned mechanically through its ionic crosslinking property to modify the scaffold's porosity, strength, and stiffness. In this study, a frozen calcium chloride (CaCl2) disk technique to homogenously crosslink alginate and egg white hydrogel is presented for 2.5D culture of human salivary cells. Different EWA formulations were prepared and biologically evaluated as a spheroid-like structure platform. Although all five EWA hydrogels showed biocompatibility, the EWA with 1.5% alginate presented the highest cell viability, while EWA with 3% alginate promoted the formation of larger size salivary spheroid-like structures. Our EWA hydrogel has the potential to be an alternative 3D culture scaffold that can be used for studies on drug-screening, cell migration, or as an in vitro disease model. In addition, EWA can be used as a potential source for cell transplantation (i.e., using this platform as an ex vivo environment for cell expansion). The low cost of producing EWA is an added advantage.
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Alginatos/química , Clara de Ovo/química , Hidrogéis/química , Engenharia Tecidual , Alicerces Teciduais/química , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Humanos , Glândulas Salivares , Esferoides CelularesRESUMO
PURPOSE: Punctate white matter lesions (PWML) are common in preterm neonates and have also been reported in the full term. While most studies focus on white matter abnormalities, gray matter (GM) alterations are generally ignored due to the lack of abnormalities on conventional MRI. This study aims to investigate whether magnetic resonance spectroscopy is a sensitive and practical method to detect occult alterations of deep GM nuclei in these neonates. METHODS: Neonates with PWML and controls with no MRI abnormalities were retrospectively studied. Apparent diffusion coefficient values and metabolic ratios (Cho/Cr, NAA/Cho, and NAA/Cr) in the lenticular nucleus and the thalamus were compared between the PWML and control groups. RESULTS: Forty-two neonates with PWML (grades I, II, and III contained 14, 21, and 7 subjects, respectively) and 50 controls were enrolled. Apparent diffusion coefficient values in the lenticular nucleus and the thalamus were not significantly different between the PWML and the control groups. The NAA/Cho ratio was significantly lower in the PWML group than in the control group in both regions, whereas a lower NAA/Cr ratio was only observed in the thalamus. Significantly lower ratios of NAA/Cho in both regions and NAA/Cr in the thalamus were detected in the grade II and III subgroup, whereas the thalamic NAA/Cho ratio was decreased in the grade I group compared with controls. CONCLUSIONS: Magnetic resonance spectroscopy is a sensitive method for detecting the occult deep GM abnormalities for the study cohort of neonates with PWML when compared with subjects without PWML.
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Substância Cinzenta/patologia , Espectroscopia de Ressonância Magnética/métodos , Substância Branca/patologia , Estudos de Casos e Controles , Feminino , Substância Cinzenta/metabolismo , Humanos , Recém-Nascido , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Substância Branca/metabolismoRESUMO
The problem of distributed power allocation in wireless sensor network (WSN) localization systems is investigated in this paper, using the game theoretic approach. Existing research focuses on the minimization of the localization errors of individual agent nodes over all anchor nodes subject to power budgets. When the service area and the distribution of target nodes are considered, finding the optimal trade-off between localization accuracy and power consumption is a new critical task. To cope with this issue, we propose a power allocation game where each anchor node minimizes the square position error bound (SPEB) of the service area penalized by its individual power. Meanwhile, it is proven that the power allocation game is an exact potential game which has one pure Nash equilibrium (NE) at least. In addition, we also prove the existence of an ϵ -equilibrium point, which is a refinement of NE and the better response dynamic approach can reach the end solution. Analytical and simulation results demonstrate that: (i) when prior distribution information is available, the proposed strategies have better localization accuracy than the uniform strategies; (ii) when prior distribution information is unknown, the performance of the proposed strategies outperforms power management strategies based on the second-order cone program (SOCP) for particular agent nodes after obtaining the estimated distribution of agent nodes. In addition, proposed strategies also provide an instructional trade-off between power consumption and localization accuracy.
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This article investigates the traffic offloading problem in the heterogeneous network. The location of small cells is considered as an important factor in two aspects: the amount of resources they share for offloaded macrocell users and the performance enhancement they bring after offloading. A location-aware incentive mechanism is therefore designed to incentivize small cells to serve macrocell users. Instead of taking the amount of resources shared as the basis of the reward division, the performance promotion brought to the macro network is taken. Meanwhile, in order to ensure the superiority of small cell users, the significance of them weighs heavier than macrocell users instead of being treated equally. The offloading problem is formulated as a Stackelberg game where the macro cell base station is the leader and small cells are followers. The Stackelberg equilibrium of the game is proved to be existing and unique. It is also proved to be the optimum of the proposed problem. Simulation and numerical results verify the effectiveness of the proposed method.
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BACKGROUND: Tinospora sagittata (Oliv.) Gagnep. var. craveniana (S.Y.Hu) Lo (TSG) is a traditional Chinese herb that has been used for the treatment of upper respiratory tract infection and has anti-bacterial and anti-ulcer activity. Our study investigated the bactericidal effects of TSG and its major component, palmatine, against a Helicobacter pylori (H. pylori) strain isolated from pig and the standard strain H. pylori SS1 in vitro and in vivo. METHODS: H. pylori was isolated from pig and named H. pylori SCYA201401. For in vitro experiments, the inhibitory activity of TSG and palmatine against H. pylori SCYA201401 and H. pylori SS1 were tested by use of the agar cup diffusion technique. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined from the absence of H. pylori colonies on agar plates. Time-kill curves were used to evaluate bactericidal activity; the average number of colonies was calculated at 0 to 48 h after liquid incubation, with concentrations of drugs at 0.5, 1, and 2 × MIC. For in vivo experiments, H. pylori SCYA201401-infected mice were randomly divided into TSG, palmatine, triple therapy (omeprazole, clarithromycin, and amoxicillin), blank control, and model groups. The eradication ratios were determined by use of rapid urease tests and bacterial culture. RESULTS: In vitro, the MIC and MBC of TSG against H. pylori SCYA201401 and SS1 were both 6250 µg/mL, whereas palmatine against H. pylori SCYA201401 was 6.25 µg/mL and against H. pylori SS1 was 3.12 µg/mL. The time-kill curves showed a dose-dependent, progressive decline in the numbers of viable bacteria up to 40 h. In vivo, the eradication ratios in the TSG and palmatine groups of mice were 80 and 50 % compared with 70 % in the triple-therapy group. CONCLUSION: TSG and its major component, palmatine, have bactericidal activity against H. pylori in vitro and in vivo. The possibility that TSG or palmatine can be effective in the treatment of human and animals H. pylori infection deserves investigation.
Assuntos
Antibacterianos/farmacologia , Alcaloides de Berberina/farmacologia , Helicobacter pylori/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tinospora/química , Animais , Antibacterianos/química , Alcaloides de Berberina/química , Infecções por Helicobacter/microbiologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , SuínosRESUMO
Papaya fruits (Carica papaya L. cv 'Sui you 2') harvested with < 5% yellow surface at the blossom end were fumigated with 60 microL/L of nitric oxide for 3 h and then stored at 20 degrees C with 85% relative humility for 20 days. The effects of nitric oxide treatment on ethylene production rate, the activities of cell wall softening related enzymes including polygalacturonase, pectin methyl esterase, pectate lyase and cellulase and the levels of hormones including indole acetic acid, abscisic acid, gibberellin and zeatin riboside were examined. The results showed that papaya fruits treated with nitric oxide had a significantly lower rate of ethylene production and a lesser loss of firmness during storage. A decrease in polygalacturonase, pectin methyl esterase, pectate lyase and cellulase activities was observed in nitric oxide treated fruit. In addition, the contents of indole acetic acid, abscisic acid and zeatin riboside were reduced in nitric oxide treated fruit, but no significant reduction in the level of gibberellin was found. These results indicate that nitric oxide treatment can effectively delay the softening and ripening of papaya fruit, likely via the regulation of cell wall softening related enzymes and certain hormones.