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1.
J Vet Pharmacol Ther ; 47(3): 215-225, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38189474

RESUMO

Enrofloxacin (ENR) residues in yellow catfish (Pelteobagrus fulvidraco) often exceed the standard due to excessive use. This study explored the pharmacokinetics of ENR and its metabolite ciprofloxacin (CIP) in yellow catfish following a single dose of 10 mg/kg body weight via intramuscular injection (IM), oral gavage (PO), or a 5-h drug bath at 10 mg/L and 25°C. High-performance liquid chromatography-mass spectrometry was used to determine the ENR and CIP concentrations in various tissues. The highest ENR concentration occurred with IM administration, peaking at 4.124 mg/L in the plasma, 8.359 mg/kg in the kidney, 6.272 mg/kg in the liver, and 5.192 mg/kg in the muscle. However, PO administration resulted in the longest metabolic time, with elimination half-lives of 56.47 h in plasma, 86.43 h in the kidney, 76.25 h in the liver, and 64.75 h in muscle. Additionally, the area under the concentration-time curve values for IM, PO, and bath administration in yellow catfish plasma were 108.36, 88.96, and 22.08 mg·h/L, respectively. These results indicate the effectiveness of all three administration methods in treating bacterial diseases in yellow catfish. The selection of an appropriate administration method depends on the minimal inhibitory concentration of ENR against pathogenic bacteria. Yellow catfish subjected to PO and IM administration require longer resting periods before they can be marketed than those receiving drug bath administration.


Assuntos
Antibacterianos , Peixes-Gato , Enrofloxacina , Animais , Peixes-Gato/metabolismo , Enrofloxacina/farmacocinética , Enrofloxacina/administração & dosagem , Injeções Intramusculares/veterinária , Antibacterianos/farmacocinética , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Administração Oral , Meia-Vida , Área Sob a Curva , Ciprofloxacina/farmacocinética , Ciprofloxacina/administração & dosagem , Ciprofloxacina/sangue
2.
Plant Cell Rep ; 42(4): 707-722, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36723676

RESUMO

KEY MESSAGE: The resistance of Huaidao5 results from the high constitutive expression of tolerance genes, while that of Huaidao9 is due to the cold-induced resistance in flag leaves and panicles. The regulation mechanism of rice seedlings' cold tolerance is relatively clear, and knowledge of its underlying mechanisms at the reproductive stage is limited. We performed differential expression and co-expression network analyses to transcriptomes from panicle and flag leaf tissues of a cold-tolerant cultivar (Huaidao5), and a sensitive cultivar (Huaidao9), under reproductive-stage cold stress. The results revealed that the expression levels of genes in stress-related pathways such as MAPK signaling pathway, diterpenoid biosynthesis, glutathione metabolism, plant-pathogen interaction and plant hormone signal transduction were constitutively highly expressed in Huaidao5, especially in panicles. Moreover, the Hudaidao5's panicle sample-specific (under cold) module contained some genes related to rice yield, such as GW5L, GGC2, SG1 and CTPS1. However, the resistance of Huaidao9 was derived from the induced resistance to cold in flag leaves and panicles. In the flag leaves, the responses included a series of stress response and signal transduction, while in the panicles nitrogen metabolism was severely affected, especially 66 endosperm-specific genes. Through integrating differential expression with co-expression networks, we predicted 161 candidate genes (79 cold-responsive genes common to both cultivars and 82 cold-tolerance genes associated with differences in cold tolerance between cultivars) potentially affecting cold response/tolerance, among which 85 (52.80%) were known to be cold-related genes. Moreover, 52 (65.82%) cold-responsive genes (e.g., TIFY11C, LSK1 and LPA) could be confirmed by previous transcriptome studies and 72 (87.80%) cold-tolerance genes (e.g., APX5, OsFbox17 and OsSTA109) were located within QTLs associated with cold tolerance. This study provides an efficient strategy for further discovery of mechanisms of cold tolerance in rice.


Assuntos
Resposta ao Choque Frio , Oryza , Resposta ao Choque Frio/genética , Transcriptoma/genética , Oryza/metabolismo , Genótipo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Temperatura Baixa
3.
J Esthet Restor Dent ; 35(4): 586-595, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36621950

RESUMO

OBJECTIVE: Guided bone regeneration with titanium mesh is a commonly used bone augmentation technique. However, deformation and sliding may occur during the installation of titanium mesh, which may lead to poor accuracy of bone augmentation. This article presented three cases, which describe a tooth-supported titanium mesh bending and positioning module aiming to improve the precision of bone augmentation. CLINICAL CONSIDERATIONS: After designing the ideal bone increment volume digitally, print out the difference bone module between the ideal and existing bone mass and one or two wings. The wings are supported by the adjacent teeth to show the ideal bone mass in the patients' mouth. Finally, the titanium mesh is bent and installed in the ideal position by the module. CONCLUSIONS: A favorable outcome has been preliminarily confirmed in these cases, the average vertical bone gain was 4.16 mm and the average horizontal gain was 7.48 mm after 6 months. Using the module in the treatment of patients with bone augmentation can effectively improve the accuracy, the maximum deviation was 1.5 mm and the mean was 0.6 mm. CLINICAL SIGNIFICANCE: This study improves the bone augmentation technology with titanium mesh. The titanium mesh is fixed in the ideal position, which facilitates subsequent implantation and denture repair.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Humanos , Regeneração Óssea , Implantação Dentária Endóssea/métodos , Telas Cirúrgicas , Titânio
4.
J Sci Food Agric ; 103(11): 5277-5287, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37016843

RESUMO

BACKGROUND: Oxidation has been reported as the one of the deterioration reactions of proteins in aquatic products. Searching for new bioactive substances from marine algae has been one of the main areas in food science and additives. RESULTS: In this study, a novel protein from the red alga Porphyra haitanensis was determined after ammonium sulfate precipitation and gel filtration chromatography. It closely corresponded to the antioxidant activity and was identified as an uncharacterized protein with a molecular mass of 43 kDa, designated Ph43. Bioinformatic analysis revealed that Ph43 is a novel protein of non-phycobiliprotein family with putative chordin domains and rich in α-helical conformation. Recombinant protein (rPh43) was expressed in Escherichia coli as a Hig-tagged protein using a pET-22b vector system and purified by affinity high-performance liquid chromatography. Spectroscopy analysis revealed that there were no structural differences between rPh43 and natural recovered Ph43. Moreover, rPh43 showed equal/higher antioxidant activity compared with Ph43. rPh43 has the potential for application as a natural antioxidant for food stabilization. CONCLUSION: Our results identified a novel antioxidant protein with molecular mass of 43 kDa derived from Porphyra haitanensis that belongs to the non-phycobiliprotein family. © 2023 Society of Chemical Industry.


Assuntos
Antioxidantes , Porphyra , Antioxidantes/química , Porphyra/química , Peso Molecular , Cromatografia em Gel
5.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(3): 253-258, 2023 Mar 15.
Artigo em Zh | MEDLINE | ID: mdl-36946159

RESUMO

OBJECTIVES: To study the effect of early use of sodium valproate on neuroinflammation after traumatic brain injury (TBI). METHODS: A total of 45 children who visited in Xuzhou Children's Hospital Affiliated to Xuzhou Medical University from August 2021 to August 2022 were enrolled in this prospective study, among whom 15 healthy children served as the healthy control group, and 30 children with TBI were divided into a sodium valproate treatment group and a conventional treatment group using a random number table (n=15 each). The children in the sodium valproate treatment group were given sodium valproate in addition to conventional treatment, and those in the conventional group were given an equal volume of 5% glucose solution in addition to conventional treatment. The serum concentrations of nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3), high-mobility group box 1 (HMGB1), tumor necrosis factor-α (TNF-α), and interleukin-1ß (IL-1ß) were measured in the healthy control group on the day of physical examination and in the children with TBI on days 1, 3, and 5 after admission. Glasgow Outcome Scale-Extended (GOS-E) score was evaluated for the children with TBI 2 months after discharge. RESULTS: Compared with the healthy control group, the children with TBI had significantly higher serum concentrations of NLRP3, HMGB1, TNF-α, and IL-1ß on day 1 after admission (P<0.017). The concentration of NLRP3 on day 5 after admission was significantly higher than that on days 1 and 3 after admission in the children with TBI (P<0.017). On days 3 and 5 after admission, the sodium valproate treatment group had a significantly lower concentration of NLRP3 than the conventional treatment group (P<0.05). For the conventional treatment group, there was no significant difference in the concentration of HMGB1 on days 1, 3, and 5 after admission (P>0.017), while for the sodium valproate treatment group, the concentration of HMGB1 on day 5 after admission was significantly lower than that on days 1 and 3 after admission (P<0.017). On day 5 after admission, the sodium valproate treatment group had a significantly lower concentration of HMGB1 than the conventional treatment group (P<0.05). For the children with TBI, the concentration of TNF-α on day 1 after admission was significantly lower than that on days 3 and 5 after admission (P<0.017). On days 3 and 5 after admission, the sodium valproate treatment group had a significantly lower concentration of TNF-α than the conventional treatment group (P<0.05). The concentration of IL-1ß on day 3 after admission was significantly lower than that on days 1 and 5 after admission (P<0.017) in the children with TBI. On days 3 and 5 after admission, the sodium valproate treatment group had a significantly lower concentration of IL-1ß than the conventional treatment group (P<0.05). The GOS-E score was significantly higher in the sodium valproate treatment group than that in the conventional treatment group 2 months after discharge (P<0.05). CONCLUSIONS: Early use of sodium valproate can reduce the release of neuroinflammatory factors and improve the prognosis of children with TBI.


Assuntos
Lesões Encefálicas Traumáticas , Proteína HMGB1 , Criança , Humanos , Ácido Valproico/uso terapêutico , Projetos Piloto , Fator de Necrose Tumoral alfa , Doenças Neuroinflamatórias , Proteína 3 que Contém Domínio de Pirina da Família NLR , Estudos Prospectivos , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/patologia
6.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(10): 995-1000, 2023 Oct 15.
Artigo em Zh | MEDLINE | ID: mdl-37905754

RESUMO

OBJECTIVES: To explore the effects of somatostatin on the levels of gastrointestinal hormones and clinical outcomes in critically ill infants after gastrointestinal surgery. METHODS: Using a random number table method, critically ill infants after gastrointestinal surgery who were admitted to the Intensive Care Unit of Xuzhou Children's Hospital from June 2019 to June 2021 were randomly divided into an observation group (29 cases) and a control group (30 cases). The control group received routine treatment such as anti-infection and hemostasis after surgery, while the observation group received somatostatin in addition to the routine treatment [3.5 µg/(kg·h) infusion for 7 days]. The levels of serum gastrin (GAS), motilin (MTL), insulin, and glucagon-like peptide-1 (GLP-1) before surgery, on the 3rd day after surgery, and on the 7th day after surgery were compared between the two groups. The recovery progress and incidence of complications after surgery were also compared between the two groups. RESULTS: There was no significant difference in the levels of serum GAS, MTL, insulin, and GLP-1 between the two groups before surgery (P>0.05). On the 3rd and 7th day after surgery, the levels of serum GAS, MTL, insulin, and GLP-1 in the observation group were higher than those in the control group (P<0.05). In the observation group, the levels of GAS, MTL, insulin, and GLP-1 on the 7th day after surgery were higher than those before surgery and on the 3rd day after surgery (P<0.05), and the levels on the 3rd day after surgery were higher than those before surgery (P<0.05). There was no significant difference in the levels of serum GAS, MTL, and insulin before surgery, on the 3rd day after surgery, and on the 7th day after surgery in the control group (P>0.05). The level of GLP-1 on the 7th day after surgery was higher than that before surgery and on the 3rd day after surgery (P<0.05), and the level on the 3rd day after surgery was higher than that before surgery (P<0.05) in the control group. The observation group had shorter first time of anal exhaust, recovery time of bowel sounds, and first time of defecation after surgery compared to the control group (P<0.05). The incidence of complications after surgery in the observation group was lower than that in the control group (10% vs 33%, P<0.05). CONCLUSIONS: Somatostatin can increase the levels of serum GAS, MTL, insulin, and GLP-1 in critically ill infants after gastrointestinal surgery, promote the recovery of gastrointestinal function, and reduce the incidence of postoperative complications.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Humanos , Lactente , Estado Terminal , Peptídeo 1 Semelhante ao Glucagon , Insulina , Estudos Prospectivos , Somatostatina/uso terapêutico
7.
J Med Virol ; 94(2): 587-593, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-30942492

RESUMO

Brain dysfunction is a prerequisite for critical complications in children with hand, foot, and mouth disease (HFMD). Aquaporin 4 (AQP-4) may be involved in the pathological process of cerebral oedema and injury in children with severe and critical HFMD. This study aimed to assess the association of AQP-4 with the severity of enterovirus 71 (EV71)-associated HFMD. Children with EV71-infected HFMD were divided into a common group (clinical stage 1), a severe group (clinical stage 2), and a critical group (clinical stage 3) according to Chinese guidelines. The levels of AQP-4, interleukin-6 (IL-6), norepinephrine (NE), and neuron-specific enolase (NSE) before and after treatment were tested. Serum AQP-4, IL-6, NE, and NSE levels showed significant differences among the critical, severe, and common groups before and after treatment (P < 0.01). No significant differences in AQP-4 levels in cerebrospinal fluid (CSF) were observed between the critical and severe groups before and after treatment, but the CSF AQP-4 levels in these two groups were higher than those in the common group before treatment (P < 0.01). Serum AQP-4 levels, but not CSF AQP-4 levels, closely correlated with serum IL-6, NE, and NSE levels. These results suggest that the level of AQP-4 in serum, but not in CSF, is a candidate biomarker for evaluating the severity and prognosis of EV71-associated HFMD.


Assuntos
Aquaporina 4/sangue , Aquaporina 4/líquido cefalorraquidiano , Enterovirus Humano A/isolamento & purificação , Doença de Mão, Pé e Boca/virologia , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Pré-Escolar , Infecções por Enterovirus , Feminino , Doença de Mão, Pé e Boca/sangue , Doença de Mão, Pé e Boca/líquido cefalorraquidiano , Humanos , Lactente , Interleucina-6/sangue , Masculino , Norepinefrina/sangue , Fosfopiruvato Hidratase/sangue , Prognóstico , Curva ROC , Índice de Gravidade de Doença
8.
Mar Drugs ; 20(9)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36135734

RESUMO

The objective of this research was to investigate the antioxidant activity of Gracilarialemaneiformis polysaccharide degradation and its underlying mechanism involved in the Nrf-2/Keap-1 signaling pathway in HepG2 cells with oxidative stress induced by H2O2. The result of the scavenging ability of free radicals showed that GLP-HV (polysaccharide degraded by H2O2-vitamin C (Vc)) performed a better scavenging ability than GLP (G.lemaneiformis polysaccharide). Moreover, the scavenging ability of polysaccharide to these free radicals from strong to weak was as follows: superoxide radical, ferric ion, ABTS+, and DPPH radical, and their IC50 values were 3.56 ± 0.0028, 4.97 ± 0.18, 9.62 ± 0.35, and 23.85 ± 1.78 mg/mL, respectively. Furthermore, GLP-HV obviously relieved oxidative stress in HepG2 cells, which strengthened the activity of T-AOC, CAT, GSH-PX, and SOD, and diminished the intensity of MDA, intracellular ROS, and calcium ion based on the Nrf-2/Keap-1 signaling pathway. The PCR result revealed that polysaccharide upregulated the expression of the genes Nrf-2, HO-1, NQO-1, and ZO-1 and downregulated Keap-1. The correlation between chemical properties and antioxidant mechanism of GLP-HV was evaluated via a heat map. The results illustrated that reducing sugar and active groups presented a positive correlation, and molecular weight and viscosity exhibited a negative relation with antioxidant activity.


Assuntos
Gracilaria , Rodófitas , Antioxidantes/química , Ácido Ascórbico , Cálcio/metabolismo , Gracilaria/química , Células Hep G2 , Humanos , Peróxido de Hidrogênio , Estresse Oxidativo , Polissacarídeos/química , Espécies Reativas de Oxigênio/metabolismo , Rodófitas/metabolismo , Transdução de Sinais , Açúcares , Superóxido Dismutase/metabolismo , Superóxidos
9.
Sensors (Basel) ; 22(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35062592

RESUMO

In this paper, a mutually enhanced modeling method (MEMe) is presented for human pose estimation, which focuses on enhancing lightweight model performance, but with low complexity. To obtain higher accuracy, a traditional model scale is largely expanded with heavy deployment difficulties. However, for a more lightweight model, there is a large performance gap compared to the former; thus, an urgent need for a way to fill it. Therefore, we propose a MEMe to reconstruct a lightweight baseline model, EffBase transferred intuitively from EfficientDet, into the efficient and effective pose (EEffPose) net, which contains three mutually enhanced modules: the Enhanced EffNet (EEffNet) backbone, the total fusion neck (TFNeck), and the final attention head (FAHead). Extensive experiments on COCO and MPII benchmarks show that our MEMe-based models reach state-of-the-art performances, with limited parameters. Specifically, in the same conditions, our EEffPose-P0 with 256 × 192 can use only 8.98 M parameters to achieve 75.4 AP on the COCO val set, which outperforms HRNet-W48, but with only 14% of its parameters.


Assuntos
Processamento de Imagem Assistida por Computador , Projetos de Pesquisa , Humanos , Coluna Vertebral
10.
Molecules ; 27(12)2022 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35745050

RESUMO

Accurately characterizing the conformational variation of novel molecular assemblies is important but often ignored due to limited characterization methods. Herein, we reported the use of ion-mobility mass spectrometry (IMS/MS) to investigate the conformational changes of four azobenzene covalently functionalized Keggin hybrids (azo-Keggins, compounds 1-4). The as-prepared azo-Keggins showed the general molecular formula of [C16H36N]4[SiW11O40(Si(CH2)3NH-CO(CH2)nO-C6H4N=NC6H4-R)2] (R = H, n = 0 (1); R = NO2, n = 0 (2); R = H, n = 5 (3); R = H, n = 10 (4)). The resultant azo-Keggins maintained stable monomeric states in the gas phase with intact molecular structures. Furthermore, the subtle photo-responsive trans-cis conformational variations of azo-Keggins were clearly revealed by the molecular shape-related collision cross-section value difference ranging from 2.44 Å2 to 6.91 Å2. The longer the alkyl chains linkers were, the larger the conformational variation was. Moreover, for compounds 1 and 2, higher stability in trans-conformation can be observed, while for compounds 3 and 4, bistability can be achieved for both of them.


Assuntos
Compostos Azo , Espectrometria de Mobilidade Iônica , Ânions , Compostos Azo/química , Espectrometria de Massas , Polieletrólitos
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(7): 812-816, 2022 Jul 15.
Artigo em Zh | MEDLINE | ID: mdl-35894198

RESUMO

OBJECTIVES: To study the effect of somatostatin on postoperative gastrointestinal function and stress level in children with acute abdomen. METHODS: A total of 102 children with acute abdomen who underwent surgery in Xuzhou Children's Hospital from August 2019 to June 2021 were enrolled as subjects and were randomly divided into an observation group and a control group, with 51 children in each group. The children in the control group were given conventional treatment such as hemostasis and anti-infective therapy after surgery, and those in the observation group were given somatostatin in addition to conventional treatment. Peripheral blood samples were collected from both groups before surgery and on days 1 and 5 after surgery. The two groups were compared in terms of the serum levels of endothelin-1 (ET-1), adrenocorticotropic hormone (ACTH), cortisol, gastrin, and motilin, postoperative recovery, and the incidence rate of complications. RESULTS: There was no significant difference in the serum levels of ET-1, ACTH, cortisol, gastrin, and motilin between the two groups before surgery (P>0.05). Compared with the control group, the observation group had significantly lower serum levels of ET-1, ACTH, and cortisol on days 1 and 5 after surgery (P<0.05) and significantly higher levels of motilin and gastrin on day 5 after surgery (P<0.05). Compared with the control group, the observation group had significantly shorter time to first passage of flatus, first bowel sounds, and first defecation after surgery, as well as a significantly shorter length of hospital stay (P<0.05). The incidence rate of complications in the observation group was significantly lower than that in the control group (6% vs 24%, P<0.05). CONCLUSIONS: In children with acute abdomen, somatostatin can significantly reduce postoperative stress response, improve gastrointestinal function, and reduce the incidence rate of complications, thereby helping to achieve a good prognosis.


Assuntos
Abdome Agudo , Motilina , Abdome , Hormônio Adrenocorticotrópico , Criança , Gastrinas , Humanos , Hidrocortisona , Complicações Pós-Operatórias , Estudos Prospectivos , Somatostatina/uso terapêutico
12.
Appl Opt ; 60(11): 3031-3043, 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33983197

RESUMO

The surface figure precision, weight, and dynamic performance of spaceborne primary mirrors depend on mirror structure parameters, which are usually optimized to improve the overall performance. To realize rapid multi-objective design optimization of a primary mirror with multiple apertures, a fully parameterized primary mirror structure is established. A surrogate model based on a hybrid of improved particle swarm optimization (IPSO), adaptive genetic algorithm (IAGA), and optimized back propagation neural network (IPSO-IAGA-BPNN) is developed to replace optomechanical simulation with its high computational cost. In this model, a self-adaptive inertia weight and a modified genetic operator are introduced into the particle swarm optimization (PSO) and adaptive genetic algorithm (AGA), respectively. The connection parameters of BPNN are optimized by the IPSO-IAGA algorithm for global searching capability. Further, the proposed IPSO-IAGA-BPNN, based on a rapid multi-objective optimization framework for a fully parameterized primary mirror structure, is established. Moreover, in addition to the proposed IPSO-IAGA-BPNN model, the Kriging, RSM, BPNN, GA-BPNN, PSO-BPNN, and PSO-GA-BPNN models are also analyzed as contrast models. The comparison results indicate that the predicted value obtained by IPSO-IAGA-BPNN is superior to the six other surrogate models since its mean absolute percentage error is less than 3% and its R2 is more than 0.99. Finally, we present a Pareto-optimal primary mirror design and implement it through three optimization methods. The verification results show that the proposed method predicts mirror structural performance more accurately than existing surrogate-based methods, and promotes significantly superior computational efficiency compared to the conventional integration-based method.

13.
Opt Lett ; 45(7): 1790-1793, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32236000

RESUMO

In this Letter, we report a segmented large-scaled lightweight diffractive telescope testbed newly built in our laboratory. The telescope, consisting of one 710-mm-diameter element in the center surrounded by eight 352-mm-diameter elements and a smaller eyepiece of achromatic lenses, can realize wide-band high-resolution imaging of 0.55-0.65 µm. The stitching errors are coarsely corrected by adjusting the motion stage mounted on each element. In particular, an optical synthesis system inserted behind the eyepiece is designed to compensate the residual tip-tilt-piston errors. We present the experimental imaging result of two stitched elements, which is the first successful experimental verification obtained by a practical segmented diffractive telescope to enhance the resolution. Moreover, spatial modulation diversity technology is used to restore the synthetic image so as to improve its quality and contrast.

14.
Chemistry ; 26(70): 16802-16810, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32844449

RESUMO

Keggin clusters are the most widely used polyoxometalate building blocks for the construction advanced materials, but effective methods for precisely recognizing the isostructural analogues of Keggins are still limited. In this study we employed the zwitterionic molecule 4,4'-dipyridyl N,N'-dioxide as a recognition receptor to specifically bind to the three Keggin analogues PW12 O40 3- , PMo12 O40 3- , and SiW12 O40 4- , which separately co-assembled into three different types of spherical charged colloids of different sizes. The recognition phenomena were confirmed by electrochemical methods and their crystallization behavior. Compared with solely anion-cation interaction-driven systems, the synergism with the anion-π interactions between the superchaotropic Keggins and the electron-deficient pyridine rings is believed to enhance the recognition. This observation is intriguing as the long-range solution assembly of Keggins is mainly driven by short-range anion-π interactions. Our results show that the little-noticed hydration shell of Keggins is significantly influenced by the superchaotropic effect, leading to differentiated binding affinity to the receptors and more obvious recognition phenomena between tungsten/molybdenum Keggin analogues.

15.
Inflamm Res ; 69(3): 267-278, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31925528

RESUMO

OBJECTIVE: To explore the mechanisms of crocin against glycocalyx damage and inflammatory injury in lipopolysaccharide (LPS)-induced acute respiratory distress syndrome (ARDS) mice and LPS-stimulated human umbilical vein endothelial cells (HUVECs). METHODS: Mice were randomly divided into control, LPS, and crocin + LPS (15, 30, and 60 mg/kg) groups. HUVECs were separated into eight groups: control, crocin, matrix metalloproteinase 9 inhibitor (MMP-9 inhib), cathepsin L inhibitor (CTL inhib), LPS, MMP-9 inhib + LPS, CTL inhib + LPS, and crocin + LPS. The potential cytotoxic effect of crocin on HUVECs was mainly evaluated through methylthiazolyldiphenyl-tetrazolium bromide assay. Histological changes were assessed via hemotoxylin and eosin staining. Lung capillary permeability was detected on the basis of wet-dry ratio and through fluorescein isothiocyanate-albumin assay. Then, protein levels were detected through Western blot analysis, immunohistochemical staining, and immunofluorescence. RESULTS: This study showed that crocin can improve the pulmonary vascular permeability in mice with LPS-induced ARDS and inhibit the inflammatory signaling pathways of high mobility group box, nuclear factor κB, and mitogen-activated protein kinase in vivo and in vitro. Crocin also protected against the degradation of endothelial glycocalyx heparan sulfate and syndecan-4 by inhibiting the expressions of CTL, heparanase, and MMP-9 in vivo and in vitro. Overall, this study revealed the protective effects of crocin on LPS-induced ARDS and elaborated their underlying mechanism. CONCLUSION: Crocin alleviated LPS-induced ARDS by protecting against glycocalyx damage and suppressing inflammatory signaling pathways.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Carotenoides/farmacologia , Glicocálix/química , Inflamação/tratamento farmacológico , Síndrome do Desconforto Respiratório/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , Catepsina L/metabolismo , Sobrevivência Celular , Glucuronidase/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Lipopolissacarídeos , Pulmão/efeitos dos fármacos , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Permeabilidade , Distribuição Aleatória , Síndrome do Desconforto Respiratório/induzido quimicamente , Sindecana-4/metabolismo
16.
Nanotechnology ; 31(26): 265601, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32163939

RESUMO

High quality and high quantity few-layer graphene was successfully prepared using a new impinging jet method. Natural graphite flakes were first agitated in N-methyl pyrrolidone (NMP) with the assistance of supercritical CO2, then the half-exfoliated graphite was further stripped using the shear stress derived from the impinging jets. After the energy conversion and stress analysis of the graphite particles during the whole exfoliation process, it was revealed that the size of the target mesh, the distance between the nozzle and the target, the decompression rate, and the size of the raw materials had a significant influence on the exfoliation process. Additionally, a microscopic view of the exfoliation and dispersion mechanism of graphene in the CO2-NMP system was investigated using molecular dynamics simulation, and CO2 was found to be beneficial for the penetration of NMP into the graphite sheets. Finally, the concentration and quality characteristics of the prepared graphene were characterized using ultraviolet-visible spectroscopy, transmission electron microscopy, Raman spectroscopy, and atomic force microscopy. The maximum concentration was as high as 0.689 mg ml-1, the thickness of 68% of the product was less than 2.5 nm, and the lateral dimension was from 0.5 to 3.0 µm. These results indicate that this impinging jet method is promising for large-scale industrial production.

17.
Appl Opt ; 59(22): 6505-6516, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32749350

RESUMO

The next generation of optical telescopes will provide high-resolution imaging of celestial objects by using the aperture synthesis technique. To preserve the quality of the image, fast corrections of the pistons among subapertures have to be applied, namely, the co-phasing of the array. The image-based co-phasing method via an optimization procedure has been newly developed. Despite simplicity and strong commonality, when dealing with large piston errors, this correction method is also faced with a problem in which the metric function easily falls into the local convergence, especially in the case of broadband imaging with many subapertures. In this study, an improved stochastic parallel gradient descent (SPGD) algorithm based on heuristic search is proposed for co-phasing, termed the metaheuristic SPGD algorithm. The heuristic research scheme assists the original SPGD algorithm in getting rid of local extrema. By iterations of this algorithm, the synthetic system can be co-phased without any additional instruments and operations. The effectiveness of the proposed algorithm is verified by means of simulation. Given the efficiency and superiority, it is expected that the method proposed in this study may find wide applications in multi-aperture imaging.

18.
J Cell Biochem ; 120(2): 2594-2606, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30304554

RESUMO

Medulloblastoma (MB) is the most prevalent brain tumor that occurs during childhood and originates from cerebellar granule cell precursors. Based on recent studies, the differential expression of several microRNAs is involved in MB, while the role of microRNA-494 (miR-494) in MB remains unclear. Therefore, we conducted this study to investigate the regulative role of miR-494 in MB cells via the p38 mitogen-activated protein kinase (MAPK) signaling pathway by mediating c-myc. In the current study, MB cells were collected and transfected with miR-494 mimic, miR-494 inhibitor, siRNA- c-myc, and miR-494 inhibitor + siRNA-c-myc. The expressions of miR-494, c-myc, p38 MAPK, B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), interleukin-6 (IL-6), metadherin (MTDH), phosphatase and tensin homolog (PTEN) and survivin were determined. Cell proliferation, cell-cycle distribution, apoptosis, migration, and invasion were evaluated. The results revealed that there was a poor expression of miR-494 and high expression of c-myc in MB tissues. C-myc was determined as the target gene of miR-494. In response to miR-494 mimic, MB cells were found to have increased Bax and PTEN expressions, as well as cell number in G1 phase and cell apoptosis and decreased c-myc, p38 MAPK, Bcl-2, MTDH, IL-6, and survivin expression and cell number count in the S phase, cell proliferation, migration, and invasion. In conclusion, the results demonstrated that the upregulation of miR-494 results in the suppression of cell proliferation, migration, and invasion, while it promotes apoptosis of MB cells through the negative mediation of c-myc, which in turn inactivates the p38 MAPK pathway.

19.
Sensors (Basel) ; 19(2)2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30654489

RESUMO

Noise estimation for image sensor is a key technique in many image pre-processing applications such as blind de-noising. The existing noise estimation methods for additive white Gaussian noise (AWGN) and Poisson-Gaussian noise (PGN) may underestimate or overestimate the noise level in the situation of a heavy textured scene image. To cope with this problem, a novel homogenous block-based noise estimation method is proposed to calculate these noises in this paper. Initially, the noisy image is transformed into the map of local gray statistic entropy (LGSE), and the weakly textured image blocks can be selected with several biggest LGSE values in a descending order. Then, the Haar wavelet-based local median absolute deviation (HLMAD) is presented to compute the local variance of these selected homogenous blocks. After that, the noise parameters can be estimated accurately by applying the maximum likelihood estimation (MLE) to analyze the local mean and variance of selected blocks. Extensive experiments on synthesized noised images are induced and the experimental results show that the proposed method could not only more accurately estimate the noise of various scene images with different noise levels than the compared state-of-the-art methods, but also promote the performance of the blind de-noising algorithm.

20.
Molecules ; 24(3)2019 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-30717498

RESUMO

New 1,3,5-trimethylpyrazole-containing malonamide derivatives based on pyflubumide were designed, synthesized, and characterized using ¹H-NMR, 13C-NMR, and high-resolution mass spectra (HRMS). The results of preliminary bioassays showed that the target compounds possessed good activities against Tetranychus cinnabarinus, Plutella xylostella, and Aphis craccivora. Most of the target compounds exhibited moderate to good acaricidal activity against Tetranychus cinnabarinus at a concentration of 400 µg/mL, and some showed moderate activity at a concentration of 200 µg/mL; in particular, compounds 8m and 8p exhibited 70.0% mortality. In addition, some of the target compounds exhibited good insecticidal activities against Plutella xylostella at a concentration of 200 µg/mL, especially compounds 8i and 8o, which achieved 100.0% mortality at a concentration of 100 µg/mL. Interestingly, some of the target compounds exhibited potent anti-aphid activity against Aphis craccivora at a concentration of 200 µg/mL; furthermore, compounds 8p and 8q demonstrated 100.0% anti-aphid activity at a concentration of 50 µg/mL. The preliminary analyses of the structure⁻activity relationships (SAR) indicated that the acaricidal and insecticidal activities varied significantly depending on the type of substituent and substitution pattern, which provides guidance for the further investigation of such structural modifications.


Assuntos
Técnicas de Química Sintética , Desenho de Fármacos , Malonatos/química , Malonatos/farmacologia , Pirazóis/química , Relação Dose-Resposta a Droga , Inseticidas/síntese química , Inseticidas/química , Inseticidas/farmacologia , Malonatos/síntese química , Estrutura Molecular , Relação Estrutura-Atividade
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