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1.
Brief Bioinform ; 24(6)2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37889117

RESUMEN

Artificial intelligence (AI) approaches in cancer analysis typically utilize a 'one-size-fits-all' methodology characterizing average patient responses. This manner neglects the diverse conditions in the pancancer and cancer subtypes of individual patients, resulting in suboptimal outcomes in diagnosis and treatment. To overcome this limitation, we shift from a blanket application of statistics to a focus on the explicit recognition of patient-specific abnormalities. Our objective is to use multiomics data to empower clinicians with personalized molecular descriptions that allow for customized diagnosis and interventions. Here, we propose a highly trustworthy multiomics learning (HTML) framework that employs multiomics self-adaptive dynamic learning to process each sample with data-dependent architectures and computational flows, ensuring personalized and trustworthy patient-centering of cancer diagnosis and prognosis. Extensive testing on a 33-type pancancer dataset and 12 cancer subtype datasets underscored the superior performance of HTML compared with static-architecture-based methods. Our findings also highlighting the potential of HTML in elucidating complex biological pathogenesis and paving the way for improved patient-specific care in cancer treatment.


Asunto(s)
Inteligencia Artificial , Neoplasias , Humanos , Multiómica , Neoplasias/diagnóstico , Neoplasias/genética , Aprendizaje
2.
J Cell Mol Med ; 28(12): e18481, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38899542

RESUMEN

Bacillus subtilis relies on biofilms for survival in harsh environments. Extracellular polymeric substance (EPS) is a crucial component of biofilms, yet the dynamics of EPS production in single cells remain elusive. To unveil the modulation of EPS synthesis, we built a minimal network model comprising the SinI-SinR-SlrR module, Spo0A, and EPS. Stochastic simulations revealed that antagonistic interplay between SinI and SinR enables EPS production in bursts. SlrR widens these bursts and increases their frequency by stabilizing SinR-SlrR complexes and depleting free SinR. DNA replication and chromosomal positioning of key genes dictate pulsatile changes in the slrR:sinR gene dosage ratio (gr) and Spo0A-P levels, each promoting EPS production in distinct phases of the cell cycle. As the cell cycle lengthens with nutrient stress, the duty cycle of gr pulsing decreases, whereas the amplitude of Spo0A-P pulses elevates. This coordinated response facilitates keeping a constant proportion of EPS-secreting cells within colonies across diverse nutrient conditions. Our results suggest that bacteria may 'encode' eps expression through strategic chromosomal organization. This work illuminates how stochastic protein interactions, gene copy number imbalance, and cell-cycle dynamics orchestrate EPS synthesis, offering a deeper understanding of biofilm formation.


Asunto(s)
Bacillus subtilis , Proteínas Bacterianas , Biopelículas , Replicación del ADN , Regulación Bacteriana de la Expresión Génica , Biopelículas/crecimiento & desarrollo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Bacillus subtilis/fisiología , Replicación del ADN/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Matriz Extracelular de Sustancias Poliméricas/metabolismo , Ciclo Celular/genética
3.
BMC Surg ; 24(1): 164, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38797851

RESUMEN

PURPOSE: As a minimally invasive procedure, laser hemorrhoidoplasty (LHP) can not only relieve the symptoms of hemorrhoids, but also protect the anal cushion structure. This study aimed to investigate the clinical efficacy of LHP in the treatment of grade II hemorrhoids. METHODS: A total of 70 patients with grade II hemorrhoids were randomly assigned to receive LHP or Rubber Band Ligation (RBL) (n = 35 per group) in 2019 from a single center. The postoperative pain, bleeding, feeling of anal distension(local falling, swelling, foreign body sensation, stool) and postoperative recurrence rate were compared between the two groups. RESULTS: The postoperative pain, bleeding, and feeling of anal distension in the LHP group were improved significantly as compared with the RBL group within 2 weeks after surgery (P < 0.01). Both methods can relieve the symptoms of grade II hemorrhoids. There was no difference in the recurrence rate between the two groups at 1 year after surgery (P > 0.05). The patients in LHP group took less time to return to normal activities (P < 0.001). CONCLUSIONS: As a minimally invasive treatment, LHP is easy and not traumatic and results in mild postoperative pain and few complications. It is an ideal choice for grade II hemorrhoids.


Asunto(s)
Hemorreoidectomía , Hemorroides , Terapia por Láser , Humanos , Hemorroides/cirugía , Masculino , Ligadura/métodos , Femenino , Persona de Mediana Edad , Hemorreoidectomía/métodos , Adulto , Terapia por Láser/métodos , Resultado del Tratamiento , Dolor Postoperatorio/etiología , Dolor Postoperatorio/diagnóstico , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Recurrencia
4.
Sensors (Basel) ; 21(20)2021 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-34695983

RESUMEN

During the past decade, falling has been one of the top three causes of death amongst firefighters in China. Even though there are many studies on fall-detection systems (FDSs), the majority use a single motion sensor. Furthermore, few existing studies have considered the impact sensor placement and positioning have on fall-detection performance; most are targeted toward fall detection of the elderly. Unfortunately, floor cracks and unstable building structures in the fireground increase the difficulty of detecting the fall of a firefighter. In particular, the movement activities of firefighters are more varied; hence, distinguishing fall-like activities from actual falls is a significant challenge. This study proposed a smart wearable FDS for firefighter fall detection by integrating motion sensors into the firefighter's personal protective clothing on the chest, elbows, wrists, thighs, and ankles. The firefighter's fall activities are detected by the proposed multisensory recurrent neural network, and the performances of different combinations of inertial measurement units (IMUs) on different body parts were also investigated. The results indicated that the sensor fusion of IMUs from all five proposed body parts achieved performances of 94.10%, 92.25%, and 94.59% in accuracy, sensitivity, and specificity, respectively.


Asunto(s)
Accidentes por Caídas , Dispositivos Electrónicos Vestibles , Anciano , Humanos , Movimiento (Física) , Redes Neurales de la Computación , Muñeca
5.
Sensors (Basel) ; 19(13)2019 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-31262084

RESUMEN

Multispectral filter array (MSFA)-based imaging is a compact, practical technique for snapshot spectral image capturing and reconstruction. The imaging and reconstruction quality is highly influenced by the spectral sensitivities and spatial arrangement of channels on MSFAs, and the used reconstruction method. In order to design a MSFA with high imaging capacity, we propose a sparse representation based approach to optimize spectral sensitivities and spatial arrangement of MSFAs. The proposed approach first overall models the various errors associated with spectral reconstruction, and then uses a global heuristic searching method to optimize MSFAs via minimizing the estimated error of MSFAs. Our MSFA optimization method can select filters from off-the-shelf candidate filter sets while assigning the selected filters to the designed MSFA. Experimental results on three datasets show that the proposed method is more efficient, flexible, and can design MSFAs with lower spectral construction errors when compared with existing state-of-the-art methods. The MSFAs designed by our method show better performance than others even using different spectral reconstruction methods.

6.
BMC Complement Altern Med ; 18(1): 32, 2018 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-29378560

RESUMEN

BACKGROUND: Sheng-ji Hua-yu(SJHY) formula is one of the most useful Traditional Chinese medicine (TCM) in the treatment of the delayed diabetic wound. However, elucidating the related molecular biological mechanism of how the SJHY Formula affects excessive inflammation in the process of re-epithelialization of diabetic wound healing is a task urgently needed to be fulfilled. The objectives of this study is to evaluate the effect of antagonisic expression of pro-/anti-inflammatory factors on transforming growth factor-ß(TGF-ß) superfamily (activin and follistatin) in the process of re-epithelialization of diabetic wound healing in vivo, and to characterize the involvement of the activin/follistatin protein expression regulation, phospho-Smad (pSmad2), and Nuclear factor kappa B p50 (NF-kB) p50 in the diabetic wound healing effects of SJHY formula. METHODS: SJHY Formula was prepared by pharmaceutical preparation room of Yueyang Hospital of Integrated Traditional Chinese and Western Medicine. Diabetic wound healing activity was evaluated by circular excision wound models. Wound healing activity was examined by macroscopic evaluation. Activin/follistatin expression regulation, protein expression of pSmad2 and NF-kB p50 in skin tissue of wounds were analyzed by Real Time PCR, Western blot, immunohistochemistry and hematoxylin and eosin (H&E) staining. RESULTS: Macroscopic evaluation analysis showed that wound healing of diabetic mice was delayed, and SJHY Formula accelerated wound healing time of diabetic mice. Real Time PCR analysis showed higher mRNA expression of activin/follistatin in diabetic delayed wound versus the wound in normal mice. Western Blot immunoassay analysis showed reduction of activin/follistatin proteins levels by SJHY Formula treatment 15 days after injury. Immunohistochemistry investigated the reduction of pSmad2 and NF-kB p50 nuclear staining in the epidermis of diabetic SJHY versus diabetic control mice on day 15 after wounding. H&E staining revealed that SJHY Formula accelerated re-epithelialization of diabetic wound healing. CONCLUSION: The present study found that diabetic delayed wound healing time is closely related to the high expression level of activin/follistatin, which leads to excessive inflammation in the process of re-epithelization. SJHY Formula accelerates re-epithelialization and healing time of diabetic wounds through decreasing the high expression of activin/follistatin.


Asunto(s)
Activinas/metabolismo , Diabetes Mellitus Experimental/metabolismo , Medicamentos Herbarios Chinos/farmacología , Folistatina/metabolismo , Repitelización/efectos de los fármacos , Animales , Diabetes Mellitus Experimental/complicaciones , Medicamentos Herbarios Chinos/uso terapéutico , Femenino , Ratones , Ratones Endogámicos C57BL , Úlcera/tratamiento farmacológico
7.
Emerg Infect Dis ; 23(2): 291-295, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28098547

RESUMEN

We detected the mcr-1 gene in 21 (14.8%) Salmonella isolates from pigs at slaughter; 19 were serovar Typhimurium sequence type 34. The gene was located on IncHI2-like plasmids that also harbored IncF replicons and lacked a conjugative transfer region. These findings highlight the need to prevent further spread of colistin resistance in animals and humans.


Asunto(s)
Genes Bacterianos , Salmonelosis Animal/epidemiología , Salmonelosis Animal/microbiología , Salmonella typhimurium/clasificación , Salmonella typhimurium/genética , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/microbiología , Animales , Antibacterianos/farmacología , China/epidemiología , Farmacorresistencia Bacteriana Múltiple , Orden Génico , Genoma Bacteriano , Humanos , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Salmonella typhimurium/efectos de los fármacos , Porcinos
8.
Yi Chuan ; 39(2): 110-126, 2017 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-28242598

RESUMEN

mcr-1, the first plasmid-mediated colistin-resistance gene, can mediate polymyxin resistance and be transferred horizontally via plasmids. Many studies have confirmed its distribution via epidemic plasmids (IncI2, IncX4, IncHI2, etc.), as well as mobile genetic elements, among Enterobacteriaceae isolated from animals, humans, and the environment in 35 countries. These studies provide the basis of understanding the complicated mechanism of colistin resistance mediated by MCR-1 and its global dissemination and epidemic properties, and also enrich antimicrobial resistance mechanisms. Here, we review the latest advances in the prevalence, resistance mechanism, transfer mechanism, and genetic environments of mcr-1 in isolates recovered from various samples worldwide. Finally, we discuss the clinical risk and the corresponding solutions, aiming to provide a basis for researchers and clinical scientists to face the serious challenge of antimicrobial resistance together.


Asunto(s)
Colistina/farmacología , Farmacorresistencia Microbiana/genética , Proteínas de Escherichia coli/genética , Animales , Humanos , Plásmidos
9.
Tumour Biol ; 35(9): 8829-36, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24880588

RESUMEN

Molecular biomarkers that can be detected in easily accessible body fluids have been proposed as non-invasive, cost-effective, and useful tools for cancer diagnosis. Recently, extensive research has explored the involvement of the aberrant expression of microRNA-21 (miRNA-21, miR-21) in lung cancer. Inconsistent results, however, have prevented its widespread use in diagnosis. In light of this situation, our meta-analysis aimed to systematically determine whether aberrant miR-21 expression can distinguish patients with lung cancer from cancer-free controls with a high level of diagnostic accuracy. A comprehensive literature search for relevant studies published before December 23, 2013 was conducted in the MEDLINE, EMBASE, the Cochrane Library, and three Chinese databases. The pooled sensitivity, specificity and other parameters were used to assess the overall performance of miR-21-based assays. Statistical analysis was conducted using the STATA 11.0 software. Eleven research articles involving 676 patients with lung cancer and 529 healthy controls were considered eligible for inclusion in the present meta-analysis. The following summary parameters were calculated from all the included studies: sensitivity of 0.66 (95 % confidence interval [CI]: 0.57-0.74), specificity of 0.82 (95 % CI: 0.74-0.88), positive likelihood ratio (PLR) of 3.70 (95 % CI: 2.50-5.60), negative likelihood ratio (NLR) of 0.42 (95 % CI: 0.32-0.54); diagnostic odds ratio (DOR) of 9.00 (95 % CI: 5.00-16.00), and area under the curve (AUC) of 0.81 (95 % CI: 0.77-0.84). In addition, we added two pre-specified covariates (ethnicity and specimen types) to the bivariate model to assess their impact on the diagnostic value of miR-21 for lung cancer. Similar results were also observed in subgroup analyses, indicating a relatively low level of accuracy. The current meta-analysis indicates that a single miR-21 may not be sufficient to identify lung cancer and that more miRNAs should be used to detect lung carcinoma.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , MicroARNs/genética , Diagnóstico Diferencial , Humanos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad
10.
Vet Microbiol ; 291: 110014, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38335675

RESUMEN

It is widely known that integrative and conjugative elements (ICEs) play an important role in the transmission of resistance genes and other exogenous genes. The present study aimed to characterize the three novel ICEs including ICEGpa76, ICEGpa44, and ICEGpa11, from Glaesserella parasuis. The ICEs from G. parasuis strains d76, Z44, and XP11 were predicted and identified by whole-genome sequencing (WGS) analysis, ICEfinder, and PCR. Characterization of G. parasuis strains carrying ICEs were determined by conjugation assay, antimicrobial susceptibility testing, WGS, phylogenetic analysis, and comparative sequence analysis.The WGS results showed that three ICEs from G. parasuis have a common genetic backbone belonging to characteristics ofthe ICEHpa1 family. The sequence comparison showed that the ICEHpa1 family has five hot spots (HSs) determined by IS6, IS110, and IS256. Moreover, two variable regions (VRs), VR1 and VR2 were determined by multidrug resistance genes and the rearrangement hotspot (rhs) family, respectively. VR1 consists of multidrug resistance genes, ISApl1s, and other accessory genes, while VR2 is composed of IS4, rhs family, transposase, and hypothetical protein genes. Conjugation experiments and MICs revealed that three ICEs could be transferred to G. parasuis strain IV52, indicating these three ICEs could be transmitted horizontally among G. parasuis strains. Additionally, the difference in resistance genes from ICEs might be due to the insertion function of the ISApl1s in VR1, and the rhs family in VR2 might evolve andthen be stably inherited in G. parasuis. These results further elucidated the transmission mechanism of exogenous genes in G. parasuis.


Asunto(s)
Conjugación Genética , Genes MDR , Animales , Filogenia
11.
Sci Adv ; 10(15): eadn1305, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38608021

RESUMEN

The structural identification and efficient synthesis of bioactive 2,6-dideoxyglycosides are daunting challenges. Here, we report the total synthesis and structural revision of a series of 2,6-dideoxyglycosides from folk medicinal plants Ecdysanthera rosea and Chonemorpha megacalyx, which feature pregnane steroidal aglycones bearing an 18,20-lactone and glycans consisting of 2,6-dideoxy-3-O-methyl-ß-pyranose residues, including ecdysosides A, B, and F and ecdysantheroside A. All the eight possible 2,6-dideoxy-3-O-methyl-ß-pyranoside stereoisomers (of the proposed ecdysantheroside A) have been synthesized that testify the effective gold(I)-catalyzed glycosylation methods for the synthesis of various 2-deoxy-ß-pyranosidic linkages and lays a foundation via nuclear magnetic resonance data mapping to identify these sugar units which occur promiscuously in the present and other natural glycosides. Moreover, some synthetic natural compounds and their isomers have shown promising anticancer, immunosuppressive, anti-inflammatory, and anti-Zika virus activities.


Asunto(s)
Oro , Imagen por Resonancia Magnética , Glicosilación , Tecnología , Espectroscopía de Resonancia Magnética
12.
Nanomaterials (Basel) ; 13(6)2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36986008

RESUMEN

The selector is an indispensable section of the phase change memory (PCM) chip, where it not only suppresses the crosstalk, but also provides high on-current to melt the incorporated phase change material. In fact, the ovonic threshold switching (OTS) selector is utilized in 3D stacking PCM chips by virtue of its high scalability and driving capability. In this paper, the influence of Si concentration on the electrical properties of Si-Te OTS materials is studied; the threshold voltage and leakage current remain basically unchanged with the decrease in electrode diameter. Meanwhile, the on-current density (Jon) increases significantly as the device is scaling down, and 25 MA/cm2 on-current density is achieved in the 60-nm SiTe device. In addition, we also determine the state of the Si-Te OTS layer and preliminarily obtain the approximate band structure, from which we infer that the conduction mechanism conforms to the Poole-Frenkel (PF) model.

13.
Front Microbiol ; 14: 1153740, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37260682

RESUMEN

This study aimed to characterize two novel mcr-1 variants, mcr-1.35 and mcr-1.36, which originated from Moraxella spp. that were isolated from diseased pigs in China. The Moraxella spp. carrying novel mcr-1 variants were subjected to whole-genome sequencing (WGS) and phylogenetic analysis based on the 16S rRNA gene. The mcr-1 variants mcr-1.35 and mcr-1.36 were characterized using phylogenetic analysis, a comparison of genetic environments, and protein structure prediction. The WGS indicated that two novel mcr-1 variants were located in the chromosomes of three Moraxella spp. with a genetic environment of mcr-1-pap2. In addition to the novel colistin resistance genes mcr-1.35 and mcr-1.36, the three Moraxella spp. contained other antimicrobial resistance genes, including aac(3)-IId, tet(O), sul2, floR, and blaROB-3. A functional cloning assay indicated that either the mcr-1.35 or mcr-1.36 gene could confer resistance to colistin in Escherichia coli DH5α and JM109. The nucleotide sequences of mcr-1.35 and mcr-1.36 presented 95.33 and 95.33% identities, respectively, to mcr-1.1. The phylogenetic analysis showed that mcr-1.35 and mcr-1.36 were derived from Moraxella spp. that belonged to subclades that were different from those of the mcr-1 variants (mcr-1.1 to mcr-1.34 except mcr-1.10) originating from Enterobacteriaceae. The deduced amino acid sequences of MCR-1.35 (MCR-1.36) showed 96.67% (96.49%), 82.59% (82.04%), 84.07% (83.52%), 55.52% (55.17%), 59.75% (59.57%), and 61.88% (61.69%) identity to MCR-1.10, MCR-2.2, MCR-6.1, MCR-LIN, MCR-OSL, and MCR-POR, respectively, that originated from Moraxella sp. Notably, protein structure alignment showed only a few changes in amino acid residues between MCR-1.1 and MCR-1.35, as well as between MCR-1.1 and MCR-1.36. In conclusion, this study identified Moraxella spp. carrying two novel mcr-1 variants, mcr-1.35 and mcr-1.36, conferring resistance to colistin, which were isolated from pig farms in China. In addition, mcr-like variants were observed to be located in the chromosomes of some species of Moraxella isolated from pig samples.

14.
J Glob Antimicrob Resist ; 35: 163-171, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37726088

RESUMEN

OBJECTIVES: The aim of this study was to characterize the floR-carrying plasmids originating from Glaesserella parasuis and Actinobacillus indolicus isolated from pigs with respiratory disease in China. METHODS: A total of 125 G. parasuis and 28 A. indolicus strains collected between 2009 and 2022 were screened for florfenicol resistance. Characterization of floR-positive isolates and plasmids were determined by antimicrobial susceptibility testing, serotyping, multilocus sequence typing (MLST), conjugation and transformation assays, whole-genome sequencing (WGS), and phylogenetic analysis. RESULTS: One A. indolicus and six G. parasuis were identified as positive for floR. The six G. parasuis were assigned to four different serovars, including serovars 6, 7, 9, and unknown. In addition to strain XP11, six floR genes were located on plasmids. The six floR-bearing plasmids could be transformed into Pasteurella multocida and divided into two different types, including ∼5000 bp and ∼6000 bp plasmids. The ∼5000 bp plasmids consisting of rep, lysR, mobB, and floR genes, exhibited high similarity among Pasteurellaceae bacteria. Furthermore, the ∼6000 bp plasmids, consisting of rep, lysR, mobC, mobA/L, and floR genes, showed high similarity between G. parasuis and Actinobacillus Spp. Notably, WGS results showed that the floR modules of the two types of plasmids could be transferred and integrated into the diverse Pasteurellaceae- origined plasmids. CONCLUSION: This study firstly reported the characterization of floR-carrying plasmids from A. indolicus and a non-virulent serovar of G. parasuis in pigs in China and elucidated the transmission mechanism of the floR resistance gene among the Pasteurellaceae family.


Asunto(s)
Actinobacillus , Antibacterianos , Animales , Porcinos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Tipificación de Secuencias Multilocus , Filogenia , Plásmidos/genética , Actinobacillus/genética
15.
Viruses ; 15(8)2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37632093

RESUMEN

Porcine sapelovirus (PSV) is a ubiquitous virus in farmed pigs that is associated with SMEDI syndrome, polioencephalomyelitis, and diarrhea. However, there are few reports on the prevalence and molecular characterization of PSV in Fujian Province, Southern China. In this study, the prevalence of PSV and a poetical combinative strain PSV2020 were characterized using real-time PCR, sequencing, and bioinformatics analysis. As a result, an overall sample prevalence of 30.8% was detected in 260 fecal samples, and a farm prevalence of 76.7% was observed in 30 Fujian pig farms, from 2020 to 2022. Noteably, a high rate of PSV was found in sucking pigs. Bioinformatics analysis showed that the full-length genome of PSV2020 was 7550 bp, and the genetic evolution of its ORF region was closest to the G1 subgroup, which was isolated from Asia and America; the similarity of nucleotides and amino acids to other PSVs was 59.5~88.7% and 51.7~97.0%, respectively. However, VP1 genetic evolution analysis showed a distinct phylogenetic topology from the ORF region; PSV2020 VP1 was closer to the DIAPD5469-10 strain isolated from Italy than strains isolated from Asia and America, which comprise the G1 subgroup based on the ORF region. Amino acid discrepancy analysis illustrated that the PSV2020 VP1 gene inserted twelve additional nucleotides, corresponding to four additional amino acids (STAE) at positions 898-902 AAs. Moreover, a potential recombination signal was observed in the 2A coding region, near the 3' end of VP1, owing to recombination analysis. Additionally, 3D genetic evolutionary analysis showed that all reference strains demonstrated, to some degree, regional conservation. These results suggested that PSV was highly prevalent in Fujian pig farms, and PSV2020, a PSV-1 genotype strain, showed gene diversity and recombination in evolutionary progress. This study also laid a scientific foundation for the investigation of PSV epidemiology, molecular genetic characteristics, and vaccine development.


Asunto(s)
Aminoácidos , Enterovirus Porcinos , Porcinos , Animales , Prevalencia , Granjas , Filogenia , China/epidemiología , Variación Genética , Recombinación Genética
16.
Nat Commun ; 14(1): 6095, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37773231

RESUMEN

Arsenic is an essential dopant in conventional silicon-based semiconductors and emerging phase-change memory (PCM), yet the detailed functional mechanism is still lacking in the latter. Here, we fabricate chalcogenide-based ovonic threshold switching (OTS) selectors, which are key units for suppressing sneak currents in 3D PCM arrays, with various As concentrations. We discovered that incorporation of As into GeS brings >100 °C increase in crystallization temperature, remarkably improving the switching repeatability and prolonging the device lifetime. These benefits arise from strengthened As-S bonds and sluggish atomic migration after As incorporation, which reduces the leakage current by more than an order of magnitude and significantly suppresses the operational voltage drift, ultimately enabling a back-end-of-line-compatible OTS selector with >12 MA/cm2 on-current, ~10 ns speed, and a lifetime approaching 1010 cycles after 450 °C annealing. These findings allow the precise performance control of GeSAs-based OTS materials for high-density 3D PCM applications.

17.
mBio ; 14(4): e0044223, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37314200

RESUMEN

Conjugative plasmids play a vital role in bacterial evolution and promote the spread of antibiotic resistance. They usually cause fitness costs that diminish the growth rates of the host bacteria. Compensatory mutations are known as an effective evolutionary solution to reduce the fitness cost and improve plasmid persistence. However, whether the plasmid transmission by conjugation is sufficient to improve plasmid persistence is debated since it is an inherently costly process. Here, we experimentally evolved an unstable and costly mcr-1 plasmid pHNSHP24 under laboratory conditions and assessed the effects of plasmid cost and transmission on the plasmid maintenance by the plasmid population dynamics model and a plasmid invasion experiment designed to measure the plasmid's ability to invade a plasmid-free bacterial population. The persistence of pHNSHP24 improved after 36 days evolution due to the plasmid-borne mutation A51G in the 5'UTR of gene traJ. This mutation largely increased the infectious transmission of the evolved plasmid, presumably by impairing the inhibitory effect of FinP on the expression of traJ. We showed that increased conjugation rate of the evolved plasmid could compensate for the plasmid loss. Furthermore, we determined that the evolved high transmissibility had little effect on the mcr-1-deficient ancestral plasmid, implying that high conjugation transfer is vital for maintaining the mcr-1-bearing plasmid. Altogether, our findings emphasized that, besides compensatory evolution that reduces fitness costs, the evolution of infectious transmission can improve the persistence of antibiotic-resistant plasmids, indicating that inhibition of the conjugation process could be useful to combat the spread of antibiotic-resistant plasmids. IMPORTANCE Conjugative plasmids play a key role in the spread of antibiotic resistance, and they are well-adapted to the host bacteria. However, the evolutionary adaptation of plasmid-bacteria associations is not well understood. In this study, we experimentally evolved an unstable colistin resistance (mcr-1) plasmid under laboratory conditions and found that increased conjugation rate was crucial for the persistence of this plasmid. Interestingly, the evolved conjugation was caused by a single-base mutation, which could rescue the unstable plasmid from extinction in bacterial populations. Our findings imply that inhibition of the conjugation process could be necessary for combating the persistence of antibiotic-resistance plasmids.


Asunto(s)
Antibacterianos , Bacterias , Plásmidos/genética , Farmacorresistencia Microbiana/genética , Bacterias/genética , Mutación , Antibacterianos/farmacología
18.
Int J Antimicrob Agents ; 60(3): 106643, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35872294

RESUMEN

INTRODUCTION: Rapid dissemination of plasmid-borne polymyxin resistance mcr-1 genes threatens the efficacy of polymyxins. Acquisition of mcr-1 imposes a fitness cost on bacteria; identifying the molecular mechanisms underpinning this fitness cost will help in the development of adjunctive antimicrobial therapies that target polymyxin-resistant Gram-negative pathogens. METHODS: Phenotypic assays and transcriptomics were acquired to investigate the impact of mcr-1 expression on membrane characteristics and transcriptomic responses in Escherichia coli TOP10 carrying the empty vector pBAD (TOP10+pBAD) and harbouring pBAD-mcr-1 (TOP10+pBAD-mcr-1). RESULTS: The overexpression of mcr-1 increased outer membrane permeability and caused membrane depolarisation, reflective of the transcriptomic results that showed downregulation of multiple genes involved in lipopolysaccharide core and O-antigen biosynthesis. Overexpression of mcr-1 also caused considerable gene expression changes in pathways involving carbohydrate metabolism (phosphotransferase system, pentose phosphate pathway, and pantothenate and coenzyme A biosynthesis), ABC transporters and intracellular responses to stress, especially those associated with oxidative and nucleic acid damage. Expression of mcr-1 also triggered the production of reactive oxygen species. CONCLUSION: These findings indicate that overexpression of mcr-1 results in persistent transcriptomic changes that primarily involve disruption to cell envelope synthesis via the reduction of LPS modifications, as well as dysregulation of carbon metabolism, redox balance and nucleic acids. These consequences of expression dysregulation may act as the main factors that impose a fitness cost with mcr-1 expression.


Asunto(s)
Proteínas de Escherichia coli , Ácidos Nucleicos , Antibacterianos/farmacología , Carbono , Colistina/metabolismo , Colistina/farmacología , Farmacorresistencia Bacteriana/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Pruebas de Sensibilidad Microbiana , Ácidos Nucleicos/metabolismo , Oxidación-Reducción , Plásmidos , Polimixinas
19.
Infect Drug Resist ; 15: 7227-7234, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36533252

RESUMEN

Purpose: The objective of this study was to elucidate the characteristics and mechanism of formation of the fusion plasmid pHNSHP24 carrying mcr-1.1. Materials and Methods: mcr-1.1-bearing Escherichia coli SHP24 and the corresponding transconjugant were subjected to whole-genome sequencing (WGS) combining the Illumina and MinION platforms to obtain the complete sequences of the fusion plasmid and its original plasmids. Results: Complete sequence analysis and S1 nuclease-pulsed field gel electrophoresis (S1-PFGE) results indicated that E. coli SHP24 carried four plasmids: mcr-1.1-harboring phage-like plasmid pHNSHP24-3, F53:A-:B- plasmid pHNSHP24-4, pHNSHP24-1, and pHNSHP24-2. However, the plasmid pHNSHP24 carrying mcr-1.1 presents in the transconjugant differed from the four plasmids in the donor strain SHP24. Further analysis showed that pHNSHP24 may be the fusion product of pHNSHP24-3 and pHNSHP24-4 and is formed through a replicative transposition mechanism mediated by IS26 in E. coli SHP24. Conclusion: This study is the first to report the fusion of an mcr-1.1-harboring phage-like pO111 plasmid and an F53:A-:B- plasmid mediated by IS26. Our findings revealed the role of phage-like and fusion plasmids in the dissemination of mcr-1.1.

20.
Mitochondrial DNA B Resour ; 6(1): 58-59, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33521266

RESUMEN

Cyperus rotundus L. (C. rotundus) is a sedge belonging to the family Cyperaceae and is widely distributed in tropical and warmer temperate regions worldwide. It is one of the oldest traditional medicinal herbs in China, India, Japan, and Korea. In this study, we sequenced the complete chloroplast genome of C. rotundus on the Illumina HiSeq Platform. The chloroplast genome is 182,986 bp in length, with a typical quadripartite structure and consisting of a pair of inverted repeat (IR) regions (35,969 bp) separated by a large single-copy (LSC) region (100,733 bp) and a small single-copy (SSC) region (10,315 bp). It was predicted to contain a total of 133 genes, with an overall GC content of 33.26%. Phylogenetic analysis suggested C. rotundus is sister to Eleocharis celluosa and Eleocharis dulcis.

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