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1.
Artículo en Inglés | MEDLINE | ID: mdl-38226566

RESUMEN

A mesophilic, anaerobic, endospore-forming, fermentative bacterium designated strain 8C15bT was isolated from bank sediment of the Bach Dang Estuary, Haiphong, Vietnam. The Bach Dang Estuary, where Haiphong harbour is located, is subject to strong anthropogenic influence, resulting in high concentrations of black carbon and heavy metals. Strain 8C15bT grew optimally at 30 °C, pH 7.5 and with 2.5 % (w/v) NaCl. The main cellular fatty acids consisted of iso-C15 : 0 (51 %), iso-C15:1 ω7c (32 %) and iso-C13 : 0 (5 %). Genomic considerations of strain 8C15bT and comparisons with the phylogenetically closest strains of the genus Tepidibacter provide evidence that Tepidibacter thalassicus SC562T (=DSM 15285T), Tepidibacter formicigenes DV1184T (=DSM 15518T), Tepidibacter mesophilus B1T (=JCM 16806T) and strain 8C15bT could be differentiated at the species level. We propose the name Tepidibacter aestuarii sp. nov. for the type strain 8C15bT (=JCM 35983T=KCTC 25692T). Finally, the nickel-tolerance properties of strain 8C15bT are highlighted in this study.


Asunto(s)
Estuarios , Ácidos Grasos , Ácidos Grasos/química , Vietnam , Análisis de Secuencia de ADN , Filogenia , Composición de Base , ADN Bacteriano/genética , ARN Ribosómico 16S/genética , Técnicas de Tipificación Bacteriana , Fosfolípidos/química
2.
Med Mycol ; 62(8)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39174488

RESUMEN

The Trichophyton mentagrophytes complex comprises a group of dermatophyte fungi responsible for various dermatological infections. The increasing drug resistance of this species complex, especially terbinafine resistance of Trichophyton indotineae, is a major concern in dermatologist practice. This study provides a comprehensive analysis of T. mentagrophytes complex strains isolated from patients in Hue City, Vietnam, focusing on their phenotypic and genetic characteristics, antifungal susceptibility profiles, and molecular epidemiology. Keratinophilic fungi from dermatophytosis culture samples were identified morphologically and phenotypically, with species and genotypes confirmed by internal transcribed spacer sequencing and phylogenetic analysis. Antifungal susceptibility testing was carried out to evaluate their susceptibility to itraconazole, voriconazole, and terbinafine. The 24% (n = 27/114) of superficial mycoses were phenotypically attributed to T. mentagrophytes complex isolates. Trichophyton interdigitale, mainly genotype II*, was predominant (44.4%), followed by T. mentagrophytes genotype III* (22.2%), T. indotineae (14.8%), T. tonsurans (11.2%), and T. mentagrophytes (7.4%). While all isolates were susceptible to itraconazole and voriconazole, half of T. indotineae isolates exhibited resistance to terbinafine, linked to the Phe397Leu mutation in the SQLE protein. This study highlighted the presence of terbinafine-resistant T. indotineae isolates in Vietnam, emphasizing the need to investigate dermatophyte drug resistance and implement effective measures in clinical practice.


Species diversity within the Trichophyton mentagrophytes complex isolated from dermatophytosis in Hue City, Vietnam, was observed. Terbinafine-resistant T. indotineae isolates were detected for the first time in Vietnam, emphasizing the importance of implementing antifungal susceptibility testing to effectively manage and prevent the spread of resistant isolates.


Asunto(s)
Antifúngicos , Farmacorresistencia Fúngica , Genotipo , Pruebas de Sensibilidad Microbiana , Filogenia , Terbinafina , Tiña , Humanos , Vietnam , Antifúngicos/farmacología , Terbinafina/farmacología , Tiña/microbiología , Arthrodermataceae/efectos de los fármacos , Arthrodermataceae/genética , Arthrodermataceae/clasificación , Arthrodermataceae/aislamiento & purificación , Masculino , Análisis de Secuencia de ADN , Itraconazol/farmacología , ADN Espaciador Ribosómico/genética , Femenino , Persona de Mediana Edad , ADN de Hongos/genética , Epidemiología Molecular , Adulto , Trichophyton
3.
BMC Infect Dis ; 24(1): 508, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773469

RESUMEN

Chromobacterium violaceum is a rare but severe and often fatal cause of disease in humans. We present 2 clinical cases of sepsis and skin abscesses / cellulitis caused by C. violaceum seen in a referral hospital for infectious diseases in Vietnam. Both patients survived, but appropriate antibiotic treatment was only installed after culture of the organism. We reviewed and summarised the characteristics of C. violaceum infection and treatment.


Asunto(s)
Antibacterianos , Chromobacterium , Infecciones por Bacterias Gramnegativas , Femenino , Humanos , Antibacterianos/uso terapéutico , Celulitis (Flemón)/microbiología , Celulitis (Flemón)/tratamiento farmacológico , Chromobacterium/aislamiento & purificación , Chromobacterium/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/microbiología , Sepsis/microbiología , Sepsis/tratamiento farmacológico , Vietnam , Niño , Adolescente
4.
J Invertebr Pathol ; 206: 108164, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38960029

RESUMEN

This study aims to investigate how bioactivities of the coral surface mucus layer (SML) respond to changes in mucus-associated bacterial communities between bleached and healthy Porites lobata corals in Nha Trang Bay, Vietnam. The findings suggested that significant shifts in the mucus-associated bacterial communities were related to changes in coral health states from bleached to healthy P. lobata colonies (p < 0.05), while bacterial compositions were not significantly different across seasons and locations (p > 0.05). Of which 8 genera, Shewanella, Fusibacter, Halodesulfovibrio, Marinifilum, Endozoicomonas, Litoribacillus, Algicola, and Vibrio were present only in the SML of bleached coral while absent in the SML of the healthy one. As compared with the bleached SML, the healthy SML demonstrated stronger antibacterial activity against a coral bleaching pathogen, V. coralliilyticus, higher antitumor activity against HCT116 cell accompanied with increased induction of cleaved PARP and accelerated cell nucleic apoptosis and cycle arrest at S and G2/M phases exhibiting several typical characteristics, cell shrinkage, lost cell contact, and apoptotic body formation. Moreover, putative compounds detected at 280 nm in the healthy SML were obviously higher than those in the bleached one, probably they could be bioactive molecules responsible for competitively exclusion of pathogens, Algicola and Vibrio, from the healthy SML.


Asunto(s)
Antozoos , Moco , Animales , Antozoos/microbiología , Moco/microbiología , Humanos , Vibrio/fisiología , Vietnam , Bacterias/efectos de los fármacos , Microbiota
5.
Environ Monit Assess ; 196(8): 772, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39088135

RESUMEN

Every year, Hanoi suffers from several episodes (periods with daily concentration of PM2.5 higher than 50 µg m-3 during at least two consecutive days). These episodes are of health concern because of the high concentration of PM2.5 and/or PM0.1 and the presence of PM-bound toxic components, such as, PAHs. In this study, the concentrations of PAHs bound to PM2.5 and PM0.1 in night-time and day-time samples during episode and non-episode periods in December 2021 were determined. The concentrations of PAHs bound to PM2.5 were found to increase significantly from day-time samples of 3.24 ± 0.83 ng m-3 to night-time samples of 10.8 ± 4.45 ng m-3 in episode periods. However, PAHs bound to PM0.1 increased slightly from day-time samples of 0.58 ± 0.12 ng m-3 to night-time samples of 0.89 ± 0.30 ng m-3 in episode periods. Diagnostic ratios of PAHs indicate that biomass/coal combustion and vehicular emission are the primary sources of PAHs. The incremental lifetime cancer risk was estimated to vary from 8.7E-09 to 2.5E-08 for children and 6.7E-08 to 2.2E-07 for adults, respectively. Accordingly, loss of life expectancy was estimated at 0.11 min and 0.82 min for children and adults, respectively. These findings imply that the carcinogenic impact induced by PAHs via inhalation is negligible during the episode period.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Material Particulado , Hidrocarburos Policíclicos Aromáticos , Hidrocarburos Policíclicos Aromáticos/análisis , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Humanos , Contaminación del Aire/estadística & datos numéricos , Ciudades , Tamaño de la Partícula
6.
J Mol Recognit ; 36(7): e3019, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37061787

RESUMEN

Cell mechanics is a factor that determines cell growth, migration, proliferation, or differentiation, as well as trafficking inside the cytoplasm and organization of organelles. Knowledge about cell mechanics is critical to gaining insight into these biological processes. Here, we used atomic force microscopy to examine the elasticity, an important parameter of cell mechanics, of non-adherent Jurkat leukemic T-cells in both interphase and mitotic phases. We found that the elasticity of an individual cell does not significantly change at interphase. When a cell starts to divide, its elasticity increases in the transition from metaphase to telophase during normal division while the cell is stiffened right after it enters mitosis during abnormal division. At the end of the division, the cell elasticity gradually returned to the value of the mother cell. These changes may originate from the changes in cell surface tension during modulating actomyosin at the cleavage furrow, redistributing cell organelles, and constricting the contractile ring to sever mother cell to form daughters. The difference in elasticity patterns suggests that there is a discrepancy in the redistribution of the cell organelles during normal and abnormal division.


Asunto(s)
Mitosis , Linfocitos T , Ciclo Celular , Telofase , Interfase
7.
Blood Purif ; 52(5): 493-502, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36996789

RESUMEN

INTRODUCTION: This study aimed to evaluate the effects of dialysis on change of QT interval in pre-dialysis, 1 h after dialysis initiation, and post-dialysis period in patients on maintenance dialysis (MHD). METHODS: An observational prospective study was conducted, including 61 patients, on thrice-weekly MHD ≥3 months, and without acute diseases, at the Nephrology-Dialysis Department of a tertiary hospital in Vietnam. The exclusive criteria were atrial fibrillation, atrial flutter, branch block, prolonged QT recorded in medical history, and taking antiarrhythmic drugs lengthening QT interval before entering the study. Twelve-lead electrocardiographs and blood chemistries were done simultaneously before, 1 h after initiation, and after the dialysis session. RESULTS: The proportion of patients with prolonged QT interval increased significantly from 44.3% in pre-dialysis to 77% 1 h after dialysis initiation and 86.9% in post-dialysis session. Immediately after dialysis, the QT and QTc intervals on all 12 leads were significantly longer. Post-dialysis levels of potassium, chloride, magnesium, and urea decreased significantly from 3.97 (0.7), 98.6 (4.7), 1.04 (0.2), and 21.4 (6.1) to 2.78 (0.4), 96.6 (2.5), 0.87 (0.2), and 6.33 (2.8) mmol/L, respectively, whereas the calcium increased significantly from 2.19 (0.2) to 2.57 (0.2) mmol/L. There were significant differences in the potassium level at the dialysis initiation and its speed of reduction between the group without and with prolonged QT interval. CONCLUSIONS: There was an increased risk of prolonged QT interval in MHD patients regardless of the absence of the previous abnormal QT interval. Notably, this risk increased rapidly 1 h after the initiation of dialysis.


Asunto(s)
Fallo Renal Crónico , Humanos , Fallo Renal Crónico/complicaciones , Diálisis , Estudios Prospectivos , Diálisis Renal/efectos adversos , Arritmias Cardíacas/etiología , Potasio
8.
Chem Biodivers ; 20(6): e202300372, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37145919

RESUMEN

From the fruits of Schisandra cauliflora, five new dimethylbutyrylated dibenzocyclooctadiene lignans, named schisandracaurins A-E, were isolated using separation and chromatographic techniques. Their structures were determined by extensive analyses of HR-ESI-MS, NMR, and ECD spectra. The schisandracaurins A-E potentially inhibited NO production in LPS-activated RAW264.7 cells with their IC50 values from 21.4 to 30.3 µM.


Asunto(s)
Lignanos , Schisandra , Schisandra/química , Lipopolisacáridos/farmacología , Estructura Molecular , Frutas/química , Lignanos/química , Ciclooctanos/farmacología , Ciclooctanos/análisis , Ciclooctanos/química
9.
Chem Biodivers ; 20(9): e202300904, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37550247

RESUMEN

A chemical investigation of K. heteroclite led to isolation of two new dibenzocyclooctadienes (1 and 2) together with 14 known compounds (3-16) by using multiple chromatographic techniques. New compounds (1 and 2) were obtained and identified by spectroscopic methods (HR-ESI-MS, 1D and 2D NMR, and ECD) as well as by comparison of their experimental data with those reported in the literatures. All the isolates were evaluated for their ability to modulate TNF-α production in lipopolysaccharide (LPS) stimulated RAW264.7 cells. Among them, compound 5 displayed the most inhibition against tumor necrosis factor (TNF)-α production with IC50 value of 6.16±0.14 µM. Whereas, compounds (1, 3, and 6) showed the significant inhibition (IC50 values ranging from 9.41 to 14.54 µM), and compounds (2, 4, 9, 10, 13, 15, and 16) exhibited moderate inhibition (IC50 values ranging from 19.27 to 40.64 µM) toward TNF-α production, respectively.


Asunto(s)
Kadsura , Lignanos , Kadsura/química , Factor de Necrosis Tumoral alfa , Lignanos/farmacología , Lignanos/química , Antiinflamatorios/farmacología , Fenoles , Estructura Molecular
10.
Sensors (Basel) ; 23(17)2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37687959

RESUMEN

The maximum power point tracking (MPPT) solutions improve power generation efficiency, quickly stabilizing the output waveform of photovoltaic (PV) systems under variable operating conditions. Along with new algorithms, improved and adjusted methods to exploit energy from PV systems are increasingly being researched and proposed. However, the proposed solutions based on the traditional algorithms and their improvements have poor performance, while the advanced algorithms or hybrid methods bring high performance but need to be simplified, and the response speed is higher. Moreover, a suitable PV configuration makes choosing a simple but highly efficient algorithm, especially in low-power PV system applications such as rooftop solar power, traffic lights, and moving vehicles…where the number of PV panels is insufficient to implement flexible configurations. This paper proposes a modified version of the Perturb and Observe (MPO) algorithm to improve MPPT performance and increase convergence speed in the parallel structure of PV panels. The Short-Circuit Current (Isc) and Open-Circuit Voltage (Voc) are calculated directly at specific operating conditions to quickly determine the potential maximum power point (MPP) that will reduce power interruptions and increase power generation efficiency compared to periodic updates. Therefore, the proposed solution converges faster, with higher efficiency, and the output signal in static and dynamic MPPT situations is more stable. The results show that the highest efficiency in simulation and experiment is 99.99% and 99.93%, respectively, while the convergence speed is 0.01 s and 0.03 s, respectively. They are better than the traditional Perturb and Observe (P&O) algorithm, the Variable Step Size Perturb and Observe (VSSP&O) method, and the Particle Swarm Optimization (PSO) technique under the same operating conditions. In addition, its performance and convergence speed are also compared with the latest introduced algorithms. The results show that it is valuable and reliable for parallel PV configuration.

11.
Molecules ; 28(5)2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36903605

RESUMEN

Using essential oils to control vectors, intermediate hosts, and disease-causing microorganisms is a promising approach. The genus Croton in the family Euphorbiaceae is a large genus, with many species containing large amounts of essential oils, however, essential oil studies are limited in terms of the number of Croton species investigated. In this work, the aerial parts of C. hirtus growing wild in Vietnam were collected and analyzed by gas chromatography/mass spectrometry (GC/MS). A total of 141 compounds were identified in C. hirtus essential oil, in which sesquiterpenoids dominated, comprising 95.4%, including the main components ß-caryophyllene (32.8%), germacrene D (11.6%), ß-elemene (9.1%), α-humulene (8.5%), and caryophyllene oxide (5.0%). The essential oil of C. hirtus showed very strong biological activities against the larvae of four mosquito species with 24 h LC50 values in the range of 15.38-78.27 µg/mL, against Physella acuta adults with a 48 h LC50 value of 10.09 µg/mL, and against ATCC microorganisms with MIC values in the range of 8-16 µg/mL. In order to provide a comparison with previous works, a literature survey on the chemical composition, mosquito larvicidal, molluscicidal, antiparasitic, and antimicrobial activities of essential oils of Croton species was conducted. Seventy-two references (seventy articles and one book) out of a total of two hundred and forty-four references related to the chemical composition and bioactivity of essential oils of Croton species were used for this paper. The essential oils of some Croton species were characterized by their phenylpropanoid compounds. The experimental results of this research and the survey of the literature showed that Croton essential oils have the potential to be used to control mosquito-borne and mollusk-borne diseases, as well as microbial infections. Research on unstudied Croton species is needed to search for species with high essential oil contents and excellent biological activities.


Asunto(s)
Croton , Culicidae , Insecticidas , Aceites Volátiles , Animales , Aceites Volátiles/química , Croton/química , Vietnam , Mosquitos Vectores , Aceite de Crotón , Insecticidas/química
12.
Antimicrob Agents Chemother ; 66(11): e0032122, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36197095

RESUMEN

Critically ill patients are characterized by substantial pathophysiological changes that alter the pharmacokinetics (PK) of hydrophilic antibiotics, including carbapenems. Meropenem is a key antibiotic for multidrug-resistant Gram-negative bacilli, and such pathophysiological alterations can worsen treatment outcomes. This study aimed to determine the population PK of meropenem and to propose optimized dosing regimens for the treatment of multidrug-resistant Klebsiella pneumoniae in critically ill patients. Two plasma samples were collected from eligible patients over a dosing interval. Nonparametric population PK modeling was performed using Pmetrics. Monte Carlo simulations were applied to different dosing regimens to determine the probability of target attainment and the cumulative fraction of response, taking into account the local MIC distribution for K. pneumoniae. The targets of 40% and 100% for the fraction of time that free drug concentrations remained above the MIC (ƒT>MIC) were tested, as suggested for critically ill patients. A one-compartment PK model using data from 27 patients showed high interindividual variability. Significant PK covariates were the 8-h creatinine clearance for meropenem and the presence of an indwelling catheter for pleural, abdominal, or cerebrospinal fluid drainage for the meropenem volume of distribution. The target 100% ƒT>MIC for K. pneumoniae, with a MIC of ≤2 mg/liter, could be attained by the use of a continuous infusion of 2.0 g/day. Meropenem therapy in critically ill patients could be optimized for K. pneumoniae isolates with an MIC of ≤2 mg/liter by using a continuous infusion in settings with more than 50% isolates have a MIC of ≥32mg/L.


Asunto(s)
Enfermedad Crítica , Klebsiella pneumoniae , Humanos , Meropenem/farmacocinética , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Método de Montecarlo
13.
Ophthalmic Plast Reconstr Surg ; 38(3): 258-262, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34431822

RESUMEN

PURPOSE: To assess the long-term effectiveness of the orbital septal flap to lengthen the levator muscle in management of moderate and severe upper eyelid retraction. METHODS: This study reports 46 eyes of 43 consecutive patients with moderate or severe upper eyelid retraction who were recommended for surgery. The period of the study was between October 2016 and October 2019. All cases were evaluated for eyelid position before and at 3, 6, and 12 months after the operation. Successful outcome was defined as "perfect," "acceptable," and "failure". RESULTS: The average age was 33.3 years (range, 16-59 years). The average orbital septal flap height was 5.28 ± 0.77 mm. Before surgery, 78.3% had 1 of 3 central upper eyelid retraction (group 1), and 21.7% had 1 of 3 lateral upper eyelid retraction (group 2). During follow-up postoperatively, all eyelid parameters of upper marginal reflex distance, upper scleral show, and palpebral fissure height significantly decreased compared with preoperative values in both groups. The result was considered "perfect" or "acceptable" in 42 eyes (91.3%). However, at 12 months after surgery, of the 36 middle eyelid retraction cases (group 1), 35 (97.2%) showed a successful outcome (perfect or acceptable results), while the success rate in group 2 was 70% (7 of 10 cases), a significant difference (p = 0.008). No severe complications were seen during follow up. CONCLUSIONS: Orbital septal flap is a safe and reliable procedure for management of upper eyelid retraction of moderate and severe degree.


Asunto(s)
Blefaroplastia , Enfermedades de los Párpados , Adulto , Blefaroplastia/métodos , Enfermedades de los Párpados/etiología , Enfermedades de los Párpados/cirugía , Párpados/cirugía , Fascia , Humanos , Hiperplasia/complicaciones , Estudios Retrospectivos , Colgajos Quirúrgicos/cirugía , Trastornos de la Visión
14.
Sensors (Basel) ; 21(9)2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33925803

RESUMEN

Wireless technologies that use radio frequency (RF) waveforms are common in wireless communication systems, such as the mobile communication, satellite system, and Internet of Things (IoT) systems. It is more advantageous than wired communication because of the ease of installation. However, it can negatively impact human health if high frequencies are used to transmit data. Therefore, researchers are exploring the potential of optical wireless communication as an alternative, which uses the visible light bandwidth instead of RF waveforms. Three possibilities are being investigated: visible light communication, light fidelity, and optical camera communication. In this paper, we propose a multiple-input multiple-output modulation scheme using a light-emitting diode (LED) array, which is applicable to the IoT system, based on on-off keying modulation in the time domain. This scheme is compatible with the two popular types of camera in the market, rolling shutter cameras and global shutter cameras, as well as the closed-circuit television camera, which is used in factories, buildings, etc. Despite the small size of the LED array, implementing this scheme with 10 links in different positions at a communication distance of 20 m is possible for efficient performance (low error rate) by controlling the exposure time, shutter speed, focal length, channel coding and applying the matched filter.

15.
Telemed J E Health ; 27(6): 670-678, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33095109

RESUMEN

Background: This study aimed to investigate the needs of medical users of telemedicine robots to encourage international cooperation and development. Introduction: As the use of telemedicine expands, it is necessary to develop new systems, including robots, which consider the perceived needs of end users to ensure quality of care and positive user experience. Materials and Methods: A survey of medical staff was conducted at a hospital in Vietnam to investigate users' needs for a telemedicine robot system. Results: A total of 117 medical staff participated in the survey, comprising 74 nurses and 43 doctors. The most preferred type of robot was the humanoid type, female version, and the preferred mobility type was walking. The most requested functions were "heart rate measurement," "recognition and avoidance of obstacles," "oxygen saturation measurement," "Transmitting Medical Information," and "wireless system." In addition, the most important considerations in developing a robot system were "cleaning the robot to prevent infection," followed by "convenience of operation." Discussion: The results of this study largely supported those of similar previous studies. However, some differences may reflect the cultural variation or differences in the level of medical development across contexts. Conclusion: To apply robotic systems to help develop telemedicine internationally, it is essential to develop a robot that reflects actual users' needs. If relevant matters such as legal issues are considered and addressed, an appropriate robotic telemedicine system can be successfully developed. Consequently, telemedicine can improve the quality of local medical care, strengthen practitioner capacity, and improve outcomes.


Asunto(s)
Robótica , Telemedicina , Países en Desarrollo , Femenino , Hospitales , Humanos , Encuestas y Cuestionarios
16.
BMC Bioinformatics ; 21(1): 468, 2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-33081690

RESUMEN

BACKGROUND: Current taxonomic classification tools use exact string matching algorithms that are effective to tackle the data from the next generation sequencing technology. However, the unique error patterns in the third generation sequencing (TGS) technologies could reduce the accuracy of these programs. RESULTS: We developed a Classification tool using Discriminative K-mers and Approximate Matching algorithm (CDKAM). This approximate matching method was used for searching k-mers, which included two phases, a quick mapping phase and a dynamic programming phase. Simulated datasets as well as real TGS datasets have been tested to compare the performance of CDKAM with existing methods. We showed that CDKAM performed better in many aspects, especially when classifying TGS data with average length 1000-1500 bases. CONCLUSIONS: CDKAM is an effective program with higher accuracy and lower memory requirement for TGS metagenome sequence classification. It produces a high species-level accuracy.


Asunto(s)
Algoritmos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos
17.
BMC Plant Biol ; 20(1): 358, 2020 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-32727354

RESUMEN

BACKGROUND: Understanding the genetic diversity in endangered species that occur inforest remnants is necessary to establish efficient strategies for the species conservation, restoration and management. Panax vietnamensis Ha et Grushv. is medicinally important, endemic and endangered species of Vietnam. However, genetic diversity and structure of population are unknown due to lack of efficient molecular markers. RESULTS: In this study, we employed Illumina HiSeq™ 4000 sequencing to analyze the transcriptomes of P. vietnamensis (roots, leaves and stems). Raw reads total of 23,741,783 was obtained and then assembled, from which the generated unigenes were 89,271 (average length = 598.3191 nt). The 31,686 unigenes were annotated in different databases i.e. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, Nucleotide Collection (NR/NT) and Swiss-Prot for functional annotation. Further, 11,343 EST-SSRs were detected. From 7774 primer pairs, 101 were selected for polymorphism validation, in which; 20 primer pairs were successfully amplified to DNA fragments and significant amounts of polymorphism was observed within population. The nine polymorphic microsatellite loci were used for population structure and diversity analyses. The obtained results revealed high levels of genetic diversity in populations, the average observed and expected heterozygosity were HO = 0.422 and HE = 0.479, respectively. During the Bottleneck analysis using TPM and SMM models (p < 0.01) shows that targeted population is significantly heterozygote deficient. This suggests sign of the bottleneck in all populations. Genetic differentiation between populations was moderate (FST = 0.133) and indicating slightly high level of gene flow (Nm = 1.63). Analysis of molecular variance (AMOVA) showed 63.17% of variation within individuals and 12.45% among populations. Our results shows two genetic clusters related to geographical distances. CONCLUSION: Our study will assist conservators in future conservation management, breeding, production and habitats restoration of the species.


Asunto(s)
Etiquetas de Secuencia Expresada , Variación Genética , Repeticiones de Microsatélite , Panax/genética , Especies en Peligro de Extinción , Perfilación de la Expresión Génica , Flujo Génico , Marcadores Genéticos , Genética de Población , Secuenciación de Nucleótidos de Alto Rendimiento , Anotación de Secuencia Molecular , Vietnam
18.
J Mol Recognit ; 33(9): e2847, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32212218

RESUMEN

Mechanical characteristics of individual cells play a vital role in many biological processes and are considered as indicators of the cells' states. Disturbances including methyl-ß-cyclodextrin (MßCD) and cytochalasin D (cytoD) are known to significantly affect the state of cells, but little is known about the real-time response of single cells to these drugs in their physiological condition. Here, nanoindentation-based atomic force microscopy (AFM) was used to measure the elasticity of human embryonic kidney cells in the presence and absence of these pharmaceuticals. The results showed that depletion of cholesterol in the plasma membrane with MßCD resulted in cell stiffening whereas depolymerization of the actin cytoskeleton by cytoD resulted in cell softening. Using AFM for real-time measurements, we observed that cells mechanically responded right after these drugs were added. In more detail, the cell´s elasticity suddenly increased with increasing instability upon cholesterol extraction while it is rapidly decreased without changing cellular stability upon depolymerizing actin cytoskeleton. These results demonstrated that actin cytoskeleton and cholesterol contributed differently to the cell mechanical characteristics.


Asunto(s)
Citocalasina D/farmacología , Microscopía de Fuerza Atómica , Fenómenos Biomecánicos/efectos de los fármacos , Células HEK293 , Humanos , beta-Ciclodextrinas/farmacología
19.
Cancer Control ; 26(1): 1073274819865281, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31331197

RESUMEN

The aim of the study was to evaluate the usefulness of computed tomography (CT) and magnetic resonance imaging (MRI) for differentiating thymoma from nonthymoma abnormalities in patients with myasthenia gravis (MG). A cross-sectional study of 53 patients with MG, who had undergone surgical thymectomy, was conducted at 103 Hospital (Hanoi, Vietnam) and Cho Ray Hospital (Ho Chi Minh City, Vietnam) during August 2014 and January 2017. The CT and MRI images of patients with MG were qualitatively and quantitatively (radiodensity and chemical shift ratio [CSR]) analyzed to determine and compare their ability to distinguish thymoma from nonthymoma abnormalities. Logistic regression was used to identify the association between imaging parameters (eg, CSR) and the thymoma status. The receiver operating curve (ROC) analysis was used to determine the differentiating ability of CSR and radiodensity. As results, of the 53 patients with MG, 33 were with thymoma and 20 were with nonthymoma abnormalities. At qualitative assessment, MRI had significantly higher accuracy than did CT in differentiating thymoma from nonthymoma abnormalities (94.3% vs 83%). At quantitative assessment, both the radiodensity and CSR were significantly higher for thymoma compared with nonthymoma groups (P < .001). The ROC analysis showed that CSR had significantly higher sensitivity (Se) and specificity (Sp) than radiodensity in discriminating between the 2 groups (CSR: Se 100%, Sp 95% vs radiodensity: Se 90.9%, Sp 70%). When combining both qualitative and quantitative parameters, MRI had even higher accuracy than did CT in thymoma diagnosis (P = .031). In conclusion, chemical shift MRI was more accurate than CT for differentiating thymoma from nonthymoma in patients with MG.


Asunto(s)
Miastenia Gravis/etiología , Timoma/diagnóstico , Timo/diagnóstico por imagen , Neoplasias del Timo/diagnóstico , Adulto , Estudios Transversales , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Curva ROC , Timectomía , Timoma/complicaciones , Timoma/cirugía , Timo/cirugía , Neoplasias del Timo/complicaciones , Neoplasias del Timo/cirugía , Tomografía Computarizada por Rayos X , Adulto Joven
20.
Exp Cell Res ; 367(2): 132-136, 2018 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-29577895

RESUMEN

Cell division is managed by a complex and coordinated sequence of cytoskeleton alterations that give rise to major morphological changes. During dividing the cleavage furrow of the cell is significantly stiffened due to the accumulation of actomyosin. However, it is unclear whether the stiffness on top of the cell is changed or not. Here, we used atomic force microscopy to measure stiffness on this location of non-adhesion Jurkat T cell and its derivative D1.1 cell from interphase to cytokinesis. The results showed that during division the cell stiffness significantly increases at anaphase and telophase. These increases in cell stiffness are most likely due to the cell surface tension created by the pulling forces of the microtubules to separate sister chromatids in the anaphase and the contraction forces of the contractile ring to separate the mother cell into daughters in the telophase. The dynamic measurement of cell elasticity during cell division may be used as a tool to gain further insight into the involved molecules and mechanisms.


Asunto(s)
División Celular , Células Madre Hematopoyéticas/citología , Fenómenos Biomecánicos , Humanos , Células Jurkat , Microscopía de Fuerza Atómica
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