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1.
Front Microbiol ; 15: 1355460, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38440143

RESUMEN

Background: Helicobacter pylori (H. pylori) is thought to primarily colonize the human stomach and lead to various gastrointestinal disorders, such as gastritis and gastric cancer. Currently, main eradication treatment is triple or quadruple therapy centered on antibiotics. Due to antibiotic resistance, the eradication rate of H. pylori is decreasing gradually. Therefore, searching for anti-H. pylori drugs from herbal sources has become a strategy for the treatment. Our team proposed a Hezi Qingyou Formula (HZQYF), composed of Chebulae Fructus, Ficus hirta Vahl and Cloves, and studied its anti-H. pylori activity and mechanism. Methods: Chemical components of HZQYF were studied using UHPLC-MS/MS and HPLC. Broth microdilution method and agar dilution method were used to evaluate HZQYF's antibacterial activity. The effects of HZQYF on expression of adhesion genes (alpA, alpB, babA), urease genes (ureE, ureF), and flagellar genes (flaA, flaB) were explored using Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR) technology. Effects on morphology and permeability of the extracellular membrane were studied using scanning electron microscopy (SEM) and N-phenylnaphthalen-1-amine (NPN) uptake. Effect on urease activity was studied using a urease kinetics analysis in vitro. Immunofluorescence staining method was used to examine the effect on adhesion. Western blot was used to examine the effect on cagA protein. Results: Minimum inhibitory concentration (MIC) values of the formula against H. pylori clinical strains and standard strains were 80-160 µg/mL, and minimum bactericidal concentration (MBC) values were 160-320 µg/mL. The formula could down-regulate the expression of adhesion genes (alpA, alpB, babA), urease genes (ureE, ureF) and flagellar genes (flaA, flaB), change the morphology of H. pylori, increase its extracellular membrane permeability, and decrease its urease activity. Conclusion: Present studies confirmed that HZQYF had promising in vitro anti-H. pylori activities and demonstrated its possible mechanism of action by down-regulating the bacterial adhesion, urease, and flagellar gene expression, which provided scientific bases for further clinical investigations.

2.
Molecules ; 29(5)2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38474673

RESUMEN

1,3,6-Trigalloylglucose is a natural compound that can be extracted from the aqueous extracts of ripe fruit of Terminalia chebula Retz, commonly known as "Haritaki". The potential anti-Helicobacter pylori (HP) activity of this compound has not been extensively studied or confirmed in scientific research. This compound was isolated using a semi-preparative liquid chromatography (LC) system and identified through Ultra-high-performance liquid chromatography-MS/MS (UPLC-MS/MS) and Nuclear Magnetic Resonance (NMR). Its role was evaluated using Minimum inhibitory concentration (MIC) assay and minimum bactericidal concentration (MBC) assay, scanning electron microscope (SEM), inhibiting kinetics curves, urea fast test, Cell Counting Kit-8 (CCK-8) assay, Western blot, and Griess Reagent System. Results showed that this compound effectively inhibits the growth of HP strain ATCC 700392, damages the HP structure, and suppresses the Cytotoxin-associated gene A (Cag A) protein, a crucial factor in HP infection. Importantly, it exhibits selective antimicrobial activity without impacting normal epithelial cells GES-1. In vitro studies have revealed that 1,3,6-Trigalloylglucose acts as an anti-adhesive agent, disrupting the adhesion of HP to host cells, a critical step in HP infection. These findings underscore the potential of 1,3,6-Trigalloylglucose as a targeted therapeutic agent against HP infections.


Asunto(s)
Helicobacter pylori , Terminalia , Extractos Vegetales/química , Terminalia/química , Cromatografía Liquida , Espectrometría de Masas en Tándem , Agua
3.
Environ Toxicol ; 39(5): 3225-3237, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38357781

RESUMEN

Lung cancer (LC) is the most prevalent cancer type, with a high mortality rate worldwide. The current treatment options for LC have not been particularly successful in improving patient outcomes. Yifei Sanjie (YFSJ), a well-applicated traditional Chinese medicine formula, is widely used to treat pulmonary diseases, especially LC, yet little is known about its molecular mechanisms. This study was conducted to explore the molecular mechanism by which YFSJ ameliorated LC progression. The A549, NCI-H1975, and Calu-3 cells were treated with the YFSJ formula and observed for colony number, apoptosis, migration, and invasion properties recorded via corresponding assays. The PRMT6-YBX1-CDC25A axis was tested and verified through luciferase reporter, RNA immunoprecipitation, and chromatin immunoprecipitation assays and rescue experiments. Our results demonstrated that YFSJ ameliorated LC cell malignant behaviors by increasing apoptosis and suppressing proliferation, migration, and invasion processes. We also noticed that the xenograft mouse model treated with YFSJ significantly reduced tumor growth compared with the control untreated group in vivo. Mechanistically, it was found that YFSJ suppressed the expression of PRMT6, YBX1, and CDC25A, while the knockdown of these proteins significantly inhibited colony growth, migration, and invasion, and boosted apoptosis in LC cells. In summary, our results suggest that YFSJ alleviates LC progression via the PRMT6-YBX1-CDC25A axis, confirming its efficacy in clinical use. The findings of our study provide a new regulatory network for LC growth and metastasis, which could shed new insights into pulmonary medical research.


Asunto(s)
Neoplasias Pulmonares , MicroARNs , Humanos , Animales , Ratones , Neoplasias Pulmonares/patología , Proliferación Celular/genética , Movimiento Celular/genética , Pulmón/patología , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Proteína 1 de Unión a la Caja Y/genética , Proteína 1 de Unión a la Caja Y/metabolismo , Proteínas Nucleares/genética , Proteína-Arginina N-Metiltransferasas/genética , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteína-Arginina N-Metiltransferasas/uso terapéutico , Fosfatasas cdc25/genética , Fosfatasas cdc25/metabolismo
4.
Micromachines (Basel) ; 14(8)2023 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-37630091

RESUMEN

To automatically measure the surface profile of a cylindrical workpiece, a high-precision multi-beam optical method is proposed in this paper. First, some successive images for the cylindrical workpiece's surface are acquired by a multi-beam angle sensor under different light directions. Then, the light directions are estimated based on the feature regions in the images to calculate surface normal vectors. Finally, according to the relationship of the surface normal vector and the vertical section of the workpiece's surface, a depth map is reconstructed to achieve the curvature surface, which can be employed to measure the curvature radius of the cylindrical workpiece's surface. Experimental results indicate that the proposed measurement method can achieve good measurement precision with a mean error of the curvature radius of a workpiece's surface of 0.89% at a reasonable speed of 10.226 s, which is superior to some existing methods.

5.
Anal Methods ; 15(28): 3466-3475, 2023 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-37431579

RESUMEN

Heavy metal pollution poses a great threat to the ecological environment and human health. In particular, copper ions (Cu2+) play a vital role in regulating fundamental life behavior, and the homeostasis of Cu2+ is closely related to many physiological processes. The excessive accumulation of Cu2+ in the human body through food and drinking water will cause severe diseases. However, current conventional Cu2+ detection methods for evaluating the content of Cu2+ are unable to meet the complete requirements of practical Cu2+ analysis in the practical aquatic environment. In this work, we successfully constructed a novel fluorescent DNA aptasensor, which originated from the binding reaction between the improved DNA fluorescent light-up aptamer termed S2T3AT-GC and a small fluorescent molecule termed DFHBI-1T (S2T3AT-GC/DFHBI-1T) to realize fast and anti-interference response for Cu2+via the competitive interaction between Cu2+ and S2T3AT-GC (Cu2+/S2T3AT-GC) destroying the contained G-quadruplex structure of S2T3AT-GC. Moreover, it enables the sensitive detection of Cu2+ with a detection limit of 0.3 µM and a wide detection linear range from 0.3 to 300 µM. Moreover, with the verification of high stability in real industrial sewage samples, this aptasensor exhibits excellent detection performance for Cu2+ analysis in real water samples. Therefore, the proposed aptasensor exhibits great potential in exploring Cu2+-related environmental and ecological research.


Asunto(s)
Cobre , Aguas del Alcantarillado , Humanos , Cobre/análisis , Cobre/química , ADN , Iones , Colorantes Fluorescentes/química
6.
Opt Express ; 31(14): 23040-23055, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37475398

RESUMEN

Metal cylindrical shaft parts are critical components in industrial manufacturing that require high standards for roundness error and surface roughness. When using the self-developed multi-beam angle sensor (MBAS) to detect metal cylindrical shaft parts, the distorted multi-spots degrade the measurement accuracy due to the nonlinear distortion caused by the metal material's reflective properties and surface roughness. In this study, we propose a spot coordinate prediction network (SCPNet), which is a deep-learning neural network designed to predict spot coordinates, in combination with Hough circle detection for localization. The singular value decomposition (SVD) model is employed to eliminate the tilt error to achieve high-precision, three-dimensional (3D) surface reconstruction of metal cylindrical shaft parts. The experimental results demonstrate that SCPNet can effectively correct distorted multi-spots, with an average error of the spot center of 0.0612 pixels for ten points. The proposed method was employed to measure metal cylindrical shaft parts with radii of 10 mm, 20 mm, 35 mm, and 50 mm, with resulting standard deviation (STD) values of 0.0022 µm, 0.0026 µm, 0.0028 µm, and 0.0036 µm, respectively.

7.
Anal Chem ; 95(21): 8348-8356, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37194189

RESUMEN

Copper ions play vital roles in regulating life processes and being closely involved in several diseases such as cancer. Although detection methods based on fluorescent sensors or other strategies have been developed, it still remains a challenge to simultaneously realize the convenience, specificity, and accuracy in intracellular copper ion analysis. Herein, we propose an aptamer-functionalized DNA fluorescent sensor (AFDS) for accurate and specific detection of Cu(II) both in vitro and in cells by engineering the linkage of two DNA aptamers, namely, Lettuce aptamer and AS1411 aptamer, to achieve the manner of recognition response. Taking advantage of the functions of each aptamer, the tumor cell recognition capability and the high-contrast detection performance are simultaneously equipped in the AFDS. Furthermore, the AFDS shows high specificity and selectivity in Cu(II) response to avoid interference from common metal ions, chelators, and reactants by being associated with the irreversible interaction between nucleobases and Cu(II), which can destroy the topological structures and switch off the fluorescence of the AFDS. It also enables a sensitive in vitro detection of Cu(II) with a detection limit as lower as 0.1 µM and a wide detection linear range from 0.1 to 300 µM. The feasibility and superiority of the AFDS provide an opportunity to reveal both concentration-dependent and time-dependent intracellular Cu(II) responses in living cells. Therefore, the AFDS has achieved the novel detection performance of Cu(II) to exhibit great potential in exploring copper-related biological and pathological research.


Asunto(s)
Cobre , Metales , Cobre/química , ADN , Iones , Colorantes Fluorescentes/química
8.
Tissue Eng Part C Methods ; 29(8): 381-393, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37212303

RESUMEN

Corneal nerves originate from the ophthalmic branch of the trigeminal nerve, which enters the cornea at the limbus radially from all directions toward the central cornea. The cell bodies of the sensory neurons of trigeminal nerve are located in the trigeminal ganglion (TG), while the axons are extended into the three divisions, including ophthalmic branch that supplies corneal nerves. Study of primary neuronal cultures established from the TG fibers can therefore provide a knowledge basis for corneal nerve biology and potentially be developed as an in vitro platform for drug testing. However, setting up primary neuron cultures from animal TG has been dubious with inconsistency among laboratories due to a lack of efficient isolation protocol, resulting in low yield and heterogenous cultures. In this study, we used a combined enzymatic digestion with collagenase and TrypLE to dissociate mouse TG while preserving nerve cell viability. A subsequent discontinuous Percoll density gradient followed by mitotic inhibitor treatment effectively diminished the contamination of non-neuronal cells. Using this method, we reproducibly generated high yield and homogenous primary TG neuron cultures. Similar efficiency of nerve cell isolation and culture was further obtained for TG tissue cryopreserved for short (1 week) and long duration (3 months), compared to freshly isolated tissues. In conclusion, this optimized protocol shows a promising potential to standardize TG nerve culture and generate a high-quality corneal nerve model for drug testing and neurotoxicity studies.


Asunto(s)
Neuronas , Ganglio del Trigémino , Ratones , Animales , Ganglio del Trigémino/fisiología , Córnea
9.
Opt Express ; 31(4): 5593-5608, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36823835

RESUMEN

To solve limited efficiency and reliability issues caused by current manual quality control processes in optical lens (OL) production environments, we propose an automatic micro vision-based inspection system named MVIS used to capture the surface defect images and make the OL dataset and predictive inference. Because of low resolution and recognition, OL defects are weak, due to their ambiguous morphology and micro size, making a poor detection effect for the existing method. A deep-learning algorithm for a weak micro-defect detector named ISE-YOLO is proposed, making the best for deep layers, utilizing the ISE attention mechanism module in the neck, and introducing a novel class loss function to extract richer semantics from convolution layers and learning more information. Experimental results on the OL dataset show that ISE-YOLO demonstrates a better performance, with the mean average precision, recall, and F1 score increasing by 3.62%, 6.12% and 3.07% respectively, compared to the YOLOv5. In addition, compared with YOLOv7, which is the latest version of YOLO serials, the mean average precision of ISE-YOLO is improved by 2.58%, the weight size is decreased by more than 30% and the speed is increased by 16%.

10.
J Fish Dis ; 46(4): 381-394, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36606554

RESUMEN

Chronic disease following Nocardia seriolae infection in a wide range of aquatic animals has been reported in many Asian countries and recently in America and Mexico. This study aimed to investigate the epidemiological relationship among N. seriolae isolates in Taiwan by investigating their genotype and enzymatic activities. A total of 66 strains isolated from 14 known and four unknown host fish from five sites in Taiwan were characterized using five combined methods. High genotypic diversity was recognized among the isolates with 10 pulsotypes being identified from the pulsed-field gel electrophoresis method and 21 reptypes from the repetitive extragenic palindromic amplification method; however, no natural plasmids were detected in this bacterial population. Pulsotypes A8 and RI analysed by PFGE and repPCR, respectively, were found to be predominant within five sites in Taiwan over 17 years of isolation. Enzymatically, the majority of isolates displayed high leucine arylamidase, ß-glucosidase and α-glucosidase activities but were negative for lipase, α-galactosidase, ß-glucuronidase, N-acetyl-glucosaminidase, α-mannosidase and α-fucosidase activities. We identified a strong association between genotype and enzymatic activity since the majority of pulsotypes displayed the same type of enzymatic profile. This study provides comprehensive and potential epidemiological data, which will aid the fish farming activities and prevention method development.


Asunto(s)
Enfermedades de los Peces , Nocardiosis , Nocardia , Animales , Taiwán/epidemiología , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/microbiología , Nocardia/genética , Nocardiosis/epidemiología , Nocardiosis/veterinaria , Nocardiosis/microbiología , Genotipo , Peces/microbiología
11.
J Mater Chem B ; 11(5): 1159, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36651517

RESUMEN

Correction for 'Exploration of biomimetic poly(γ-benzyl-L-glutamate) fibrous scaffolds for corneal nerve regeneration' by Tien-Li Ma et al., J. Mater. Chem. B, 2022, 10, 6372-6379, https://doi.org/10.1039/D2TB01250B.

12.
Opt Express ; 30(17): 30466-30479, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36242150

RESUMEN

Large curvature aspheric optical elements are widely used in visual system. But its morphological detection is very difficult because its accuracy requirement is very high. When we use the self-developed multi-beam angle sensor (MBAS) to detect large curvature aspheric optical elements, the accuracy will be reduced due to spot distortion. Therefore, we propose a scheme combining distorted spot correction neural network (DSCNet) and gaussian fitting method to improve the detection accuracy of distorted spot center. We develop a spot discrimination method to determine spot region in multi-spot images. The spot discrimination threshold is obtained by the quantitative distribution of pixels in the connected domain. We design a DSCNet, which corrects the distorted spot to Gaussian spot, to extract the central information of distorted spot images by multiple pooling. The experimental results demonstrate that the DSCNet can effectively correct the distorted spot, and the spot center can be extracted to sub-pixel level, which improves the measurement accuracy of the MBAS. The standard deviations of plano-convex lenses with curvature radii of 500 mm, 700 mm and 1000 mm measured with the proposed method are respectively 0.0112 um, 0.0086 um and 0.0074 um.

13.
J Mater Chem B ; 10(33): 6372-6379, 2022 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-35950376

RESUMEN

Poly(γ-benzyl-L-glutamate) (PBG) made biomimetic scaffolds are explored as candidate materials for corneal nerve regeneration and neurotrophic keratopathy treatment. The PBG with built-in neurotransmitter glutamate was synthesized and fabricated into 3D fibrous scaffolds containing aligned fibers using electrospinning. In in vitro experiments, primary mouse trigeminal ganglia (TG) cells were used. Immunohistochemistry (IHC) analysis shows that TG cells cultured on PBG have no cytotoxic response for 21 days. Without any nerve growth factor, TG cells have the longest neurite length of 225.3 µm in the PBG group and 1.3 times the average length as compared with the polycaprolactone and no scaffold groups. Also, aligned fibers guide the neurite growth and extension unidirectionally. In vivo assays were carried out by intracorneal implantation of PBG on clinical New Zealand rabbits. The external eye photos and in vivo confocal microscopy (IVCM) show a low immune response. The corneal neural markers (ßIII tubulin and SMI312) in the IHC analysis are consistent with the position stained by glutamate of implanted scaffolds, indicating that PBG induces neurogenesis. PBG exhibits mechanical stiffness to resist material deformation possibly caused by surgical operations. The results of this study demonstrate that PBG is suitable for corneal nerve regeneration and the treatment of neurotrophic keratopathy.


Asunto(s)
Ácido Glutámico , Andamios del Tejido , Animales , Biomimética , Ratones , Regeneración Nerviosa/fisiología , Neuritas , Conejos
14.
J Fish Dis ; 45(11): 1659-1672, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35916068

RESUMEN

Edwardsiella spp. is a gram-negative, facultatively anaerobic, intracellular bacteria threatening the aquaculture industry worldwide. Noticeably, E. tarda is now genotypically classified into three distinct groups (E. tarda, E. piscicida and E. anguillarum), but morphologically, it is unclear due to varying degrees of virulence in different fish hosts. Hence, to reclassify E. tarda, we investigated differences in genotypes, phenotypes and pathogenicity. We collected Edwardsiella isolates from five different counties of Taiwan between 2017 and 2021. At first, gyrB gene was amplified for a phylogenetic tree from 40 isolates from different fish and one reference isolate, BCRC10670, from the human. Thirty-nine strains clustered into E. anguillarum, 1 strain into E. piscicida and 1 strain into E. tarda from human strain. Second, all isolates were characterized using various phenotypic (API 20E biochemical profiles) and genotypic (pulsed-field gel electrophoresis [PFGE], and virulence-related gene detection). SpeI digestion revealed 10 pulsotypes and I-CeuI into 7 pulsotypes. Virulent genes (citC, gadB, katB, mukF and fimA) confirmed in 35, 31, 28, 37 and 38 isolates, respectively. Finally, in vivo challenge test in milkfish (Chanos chanos) indicated the highest mortality from E. anguillarum. Overall, results revealed unique features with Edwardsiella spp. genotypes and pathogenicity, which are relevant to the host and provide useful insights for future vaccine development.


Asunto(s)
Edwardsiella , Infecciones por Enterobacteriaceae , Enfermedades de los Peces , Animales , Edwardsiella/genética , Edwardsiella tarda/genética , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/veterinaria , Enfermedades de los Peces/microbiología , Peces/microbiología , Humanos , Fenotipo , Filogenia , Taiwán
15.
Eur J Med Res ; 27(1): 76, 2022 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-35643539

RESUMEN

OBJECTIVE: This paper explores the effect of blood sample storage temperature and time on the erythrocyte sedimentation rate (ESR) by using the Weiss method. METHODS: Whole blood samples were collected from 80 patients and diluted 1:9 with sodium citrate solution. Each sample was split into two tubes. Using the Weiss method, ESR was tested within 1 h of collection, and one sample was placed at 4 °C and the other at room temperature (23 ± 2 °C). ESR was then measured at 2, 4, 6, 8, 12, and 24 h. The data were statistically analyzed with consideration for temperature and time. RESULTS: ESR decreased gradually over 6 h at room temperature, but the results were not statistically significant. Similarly, there was no significant difference in the decline of ESR within 8 h at 4 °C. However, ESR results decreased significantly after the samples were stored at room temperature for more than 6 h or at 4 °C for more than 8 h. ESR reduction was lower in the samples stored at 4 °C than in those stored at room temperature over the same time period. CONCLUSION: Blood sample storage temperature and duration can affect the measurement of ESR using the Weiss method. ESR testing should be completed within 4 h of sample collection in clinical work.


Asunto(s)
Temperatura Corporal , Sedimentación Sanguínea , Humanos , Temperatura , Factores de Tiempo
16.
Zhongguo Zhen Jiu ; 42(5): 486-90, 2022 May 12.
Artículo en Chino | MEDLINE | ID: mdl-35543937

RESUMEN

OBJECTIVE: To observe the effect of acupuncture combined with regular treatment and swallowing function training on pharyngeal motor, sensory function and penetration-aspiration function in patients with dysphagia after stroke. METHODS: A total of 60 patients with dysphagia after stroke were randomly divided into a control group and an observation group, 30 patients in each group. Both groups were treated with conventional treatment and swallowing function training; in addition, the observation group was treated with acupuncture at Lianquan (CV 23), Fengfu (GV 16), Yifeng (TE 17). All the treatments were given once a day, 5 days a week, for totally 4 weeks. In the two groups, the pharyngeal motor and sensory function, penetration-aspiration scores were evaluated by fiberoptic endoscopic evaluation of swallowing (FEES), and the Kubota water swallowing test scores were assessed before and after treatment, and the clinical effects were compared. RESULTS: After treatment, the pharyngeal motor and sensory function in the two groups were all higher than those before treatment (P<0.05), and those in the observation group were better than the control group (P<0.05). After treatment, the penetration-aspiration scores and Kubota water swallowing test scores in the two groups were all lower than those before treatment (P<0.05), and those in the observation group were lower than the control group (P<0.05). The total effective rate was 93.3% (28/30) in the observation group, which was better than 73.3% (22/30) in the control group (P<0.05). CONCLUSION: Acupuncture combined with regular treatment and swallowing training could improve the pharyngeal motor and sensory function, and penetration-aspiration scores in patients with dysphagia after stroke.


Asunto(s)
Terapia por Acupuntura , Trastornos de Deglución , Accidente Cerebrovascular , Puntos de Acupuntura , Deglución , Trastornos de Deglución/etiología , Trastornos de Deglución/terapia , Humanos , Accidente Cerebrovascular/complicaciones , Resultado del Tratamiento , Agua
17.
J Fish Dis ; 45(6): 771-781, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35235703

RESUMEN

Lactococcus garvieae is the etiological agent of Lactococcosis, an evolving disease affecting many fish species and causing significant economic losses worldwide. Assessing pathogen relatedness and bacterial population structure is critical for determining the epidemiology of L. garvieae infections and in establishing effective pathogen management methods. The previously published morphological and genetic studies point to a clonal population structure, as seen in other fish bacteria. In the present study, the pulsed-field gel electrophoresis (PFGE) method was utilized to define a population of 41 Taiwanese isolates from outbreaks with comparisons to four well-characterized non-Taiwanese isolates previously published. Two restriction enzymes (ApaI and SmaI) were utilized individually for PFGE analysis (cut-off value = 90.0%), revealing genetic heterogeneity across L. garvieae isolates, with ApaI and SmaI yielding 12 and seven distinct PFGE band patterns, respectively. The phylogenic analysis using internal transcribed spacer region clustered all L. garvieae isolates in the same clad. Furthermore, the electron microscopic results confirmed the absence of capsular gene cluster (CGC) in previously characterized Taiwanese vaccine strain (S3) from grey mullet. Overall, our findings emphasize the importance of analysing the morphological and genetic diversity in L. garvieae being correlated for proper taxonomic classification in vaccine strain selection and epidemiological studies.


Asunto(s)
Enfermedades de los Peces , Animales , Electroforesis en Gel de Campo Pulsado/veterinaria , Enfermedades de los Peces/microbiología , Peces , Genotipo , Lactococcus/genética , Microscopía Electrónica
18.
Talanta ; 241: 123224, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35066284

RESUMEN

Detection of heavy metal ions (HMIs) in water is an important topic in the field of analytical chemistry and environmental science. Fluorescence spectroscopy is one of the most promising strategies due to its simple instrument, low investment, rapid and convenient operation. However, current fluorescence probes for detecting HMIs are typically selective for certain ions. Herein we reported the development of a novel strategy that determined the total content of HMIs in water by fluorescence spectroscopy. A novel fluorescent nitrogen, sulfur co-doped carbon quantum dots (N, S-CQDs) was prepared via graphene oxide-assisted synthesis method. The results showed that, with the fluorescence quenching strategy, N, S-CQDs exhibited a wide linear response to a series of water-soluble metal ions. The fluorescence of N, S-CQDs is stable in a wide range of pH 4-11. The detection mechanism was proved that the integration, caused by coordination interaction between S element in N, S-CQDs and the d-orbital of associated metal ions, was the main reason for fluorescence quenching. In practice, the N, S-CQDs were applied to determine total content of HMIs in water successfully. Interestingly, further experiment proved that the N, S-CQDs could effectively remove HMIs in water after centrifuging and filtering thoroughly. It was shown that the fluorescence of N, S-CQDs was obviously quenched by the multiple-ions-involved water and scavenging effect of N, S-CQDs on HMIs with centrifugal in which the concentration of individuals meets the Chinese National Standard. This indicates that the N, S-CQDs are of a wide application prospect in water quality analysis.


Asunto(s)
Metales Pesados , Puntos Cuánticos , Carbono/química , Grafito , Humanos , Iones , Nitrógeno/química , Espectrometría de Fluorescencia/métodos
19.
Appl Opt ; 60(23): 6950-6957, 2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-34613176

RESUMEN

We propose a compressive Hadamard computational ghost imaging (CGI) method to restore clear images of objects in the underwater environment. We construct an underwater CGI system model and develop a total variation regularization prior-based compressed-sensing algorithm for the CGI image reconstruction. We design a wavelet enhancement algorithm to further denoise and enhance the quality of the CGI image. We build an experimental setup and implement a series of experiments. The effectiveness and advantages of the proposed method are experimentally investigated. The results show that the proposed method can achieve clear imaging for underwater objects with a sub-Nyquist sampling ratio. The proposed method is helpful for improving the image quality of the underwater CGI.

20.
Micromachines (Basel) ; 12(3)2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33804498

RESUMEN

In this work, a novel flexible electrically resistive-type MXene/Thermoplastic polyurethanes(TPU) based strain sensors was developed by a composite process of electrospinning (ES) and electrostatic spray deposition (ESD). Compared with other deposition processes, the sensing layer prepared by ESD has better adhesion to the ES TPU nanofiber membrane and is not easy to crack during the stretching process, thereby greatly improving the working range of the strain sensor. Furthermore, we obtained the sandwich structure easily by ES on the surface of the sensing layer again. This will help make the stress distribution more uniform during the stretching process and further increase the strain sensing range. The ESD-ES strain sensors were attached on skin to monitor various human motions. The results demonstrate that our ESD-ES strain sensors have wide application prospects in smart wearable device.

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