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1.
Sci Rep ; 14(1): 10005, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693187

RESUMO

The Three Gorges Reservoir Area (TGRA) is characterized by unique geological features that increase its susceptibility to landslides. These slopes are especially prone to destabilization when influenced by external triggers like rainfall. This research focuses on the Piansongshu landslide within the TGRA, aiming at unraveling the complex internal deformation mechanisms of landslides triggered by rainfall and providing critical insights for their prevention and mitigation. The study begins with on-site geological surveys to meticulously examine the macroscopic signs and mechanisms of deformation. It then utilizes the GeoStudio numerical simulation software to assess the landslide's stability, focusing on the changes in internal seepage fields and stability under various rainfall scenarios. Results indicate that continuous rainfall leads to the formation of a temporary saturation zone on the slope, which gradually deepens. In regions with more pronounced deformation, the infiltration line at the leading edge of accumulation notably protrudes towards the surface. Notably, the stability coefficient of the secondary shear surface of the landslide fluctuates more significantly than that of the primary sliding surface. Higher rainfall intensity and longer duration are positively correlated with a more pronounced decrease in stability coefficients. The impact on stability also varies across different rainfall patterns. As rainfall infiltrates over time, the slope's safety factor gradually decreases. This reduction continues even post-rainfall, indicating a delayed restoration period before stability returns to a safe level. These results yield valuable data for forecasting and mitigating landslides.

2.
J Antimicrob Chemother ; 79(1): 186-194, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38019670

RESUMO

OBJECTIVES: To investigate the population structure and antimicrobial resistance (AMR) of avian Pasteurella multocida in China. METHODS: Utilizing WGS analysis, we explored the phylogeny using a dataset of 546 genomes, comprising avian P. multocida isolates from China (n = 121), the USA (n = 165), Australia(n = 153), Bangladesh (n = 3) and isolates of other hosts from China (n = 104). We examined the integrative and conjugative element (ICE) structures and the distribution of their components carrying resistance genes, and reconstructed the evolutionary history of A:L1:ST129 (n = 110). RESULTS: The population structure of avian P. multocida in China was dominated by the A:L1:ST129 clone with limited genetic diversity. A:L1:ST129 isolates possessed a broader spectrum of resistance genes at comparatively higher frequencies than those from other hosts and countries. The novel putative ICEs harboured complex resistant clusters that were prevalent in A:L1:ST129. Bayesian analysis predicted that the A:L1:ST129 clone emerged around 1923, and evolved slowly. CONCLUSIONS: A:L1:ST129 appears to possess a host predilection towards avian species in China, posing a potential health threat to other animals. The complex AMR determinants coupled with high frequencies may strengthen the population dominance of A:L1:ST129. The extensive antimicrobial utilization in poultry farming and the mixed rearing practices could have accelerated AMR accumulation in A:L1:ST129. ICEs, together with their resistant clusters, significantly contribute to resistance gene transfer and facilitate the adaptation of A:L1:ST129 to ecological niches. Despite the genetic stability and slow evolution rate, A:L1:ST129 deserves continued monitoring due to its propensity to retain resistance genes, warranting global attention to preclude substantial economic losses.


Assuntos
Infecções por Pasteurella , Pasteurella multocida , Animais , Pasteurella multocida/genética , Infecções por Pasteurella/veterinária , Antibacterianos/farmacologia , Teorema de Bayes , Farmacorresistência Bacteriana , Genômica
3.
Sci Rep ; 13(1): 12926, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37558819

RESUMO

Landslides are the most widely distributed geological hazards in the Three Gorges Reservoir Area (TGRA). Understanding the deformation mechanism and evolution of landslides is of great significance for their prevention and control. In this study, we focused on the Zhangjiacitang landslide, a typical bank landslide in the TGRA. We analyzed the relationship between landslide deformation and water level fluctuations and rainfall, based on accumulated displacement monitoring data, to clarify their triggering factors and deformation mechanism. The results show that the Zhangjiacitang landslide is a large-scale accumulation landslide. Under the influence of cyclic water level fluctuations and periodic rainfall, the accumulated displacement-time curve shows a "stepped" characteristic. Heavy rainfall emerged as the primary factor influencing the deformation of the Zhangjiacitang landslide, leading to substantial deformation throughout different periods. The deformation of the landslide exhibited a positive correlation with the intensity of rainfall. In contrast, the impact of water level changes on the landslide deformation was more intricate. A rapid water level drop (> 0.3 m/d) tended to intensify the landslide deformation, while the slow water level drop period (< 0.3 m/d) did not exhibit such an effect. This study emphasizes the need for closely monitoring the landslide status during heavy rainfall periods and rapid water level decline periods. The findings of this study provide a certain reference for landslide monitoring, early warning, prevention and control in the TGRA.

4.
R Soc Open Sci ; 10(8): 230636, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37650053

RESUMO

Using load-suspended backpacks to reduce vertical peak dynamic load exerted on humans can reduce metabolic costs. However, is it possible to further reduce metabolic cost by modulating dynamic load phase shift? If so, is anti-phase better than the others? In this study, we investigated the biomechanics, energetics and trunk response under phase shifts. Nine subjects wearing an active backpack with 19.4 kg loads walked on a treadmill at 5 km h-1 with four phase shift trials (T1-T4) and a load-locked trial (LK). Our results show that anti-phase trial (T3) assists ankle more and reduces the moment and gastrocnemius medialis activity, while T4 assists knee more and reduces the moment and rectus femoris activity. Due to the load injecting more mechanical energy into human in T3 and T4, the positive centre-of-mass work is significantly reduced. However, the gross metabolic rate is lowest in T4 and 4.43% lower than in T2, which may be because the activations of erector spinae and gluteus maximus are reduced in T4. In addition, T3 increases trunk extensor effort, which may weaken the metabolic advantage. This study provides guidance for improving assistance strategies and human-load interfaces and deepens the understanding of the energetics and biomechanics of human loaded walking.

5.
Front Bioeng Biotechnol ; 11: 1140262, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37214291

RESUMO

Introduction: It is well known that the common chimpanzee, as both the closest living relative to humans and a facultative bipedal, has the capability of bipedal standing but cannot do so fully upright. Accordingly, they have been of exceeding significance in elucidating the evolution of human bipedalism. There are many reasons why the common chimpanzee can only stand with its hips-knees bent, such as the distally oriented long ischial tubercle and the almost absent lumbar lordosis. However, it is unknown how the relative positions of their shoulder-hip-knee-ankle joints are coordinated. Similarly, the distribution of the biomechanical characteristics of the lower-limb muscles and the factors that affect the erectness of standing as well as the muscle fatigue of the lower limbs remain a mystery. The answers are bound to light up the evolutional mechanism of hominin bipedality, but these conundrums have not been shed much light upon, because few studies have comprehensively explored the effects of skeletal architecture and muscle properties on bipedal standing in common chimpanzees. Methods: Thus, we first built a musculoskeletal model comprising the head-arms-trunk (HAT), thighs, shanks, and feet segments of the common chimpanzee, and then, the mechanical relationships of the Hill-type muscle-tendon units (MTUs) in bipedal standing were deduced. Thereafter, the equilibrium constraints were established, and a constrained optimization problem was formulated where the optimization objective was defined. Finally, thousands of simulations of bipedal standing experiments were performed to determine the optimal posture and its corresponding MTU parameters including muscle lengths, muscle activation, and muscle forces. Moreover, to quantify the relationship between each pair of the parameters from all the experimental simulation outcomes, the Pearson correlation analysis was employed. Results: Our results demonstrate that in the pursuit of the optimal bipedal standing posture, the common chimpanzee cannot simultaneously achieve maximum erectness and minimum muscle fatigue of the lower limbs. For uni-articular MTUs, the relationship between muscle activation, relative muscle lengths, together with relative muscle forces, and the corresponding joint angle is generally negatively correlated for extensors and positively correlated for flexors. For bi-articular MTUs, the relationship between muscle activation, coupled with relative muscle forces, and the corresponding joint angles does not show the same pattern as in the uni-articular MTUs. Discussion: The results of this study bridge the gap between skeletal architecture, along with muscle properties, and biomechanical performance of the common chimpanzee during bipedal standing, which enhances existing biomechanical theories and advances the comprehension of bipedal evolution in humans.

6.
Sensors (Basel) ; 22(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36433546

RESUMO

The foundation pit of a suspension bridge project in the Three Gorges Reservoir area is investigated in this paper. The pit is located under an unstable rock mass and landslide body; its base lithology is mudstone. The bridge foundation pit project mainly adopts blasting excavation to accelerate construction progress. However, as a hazardous technique to engineering safety, the explosion vibration easily causes deterioration of the surrounding strata, thereby inducing slope instability and rock mass collapse. Besides, three major challenges should be considered: complex terrain conditions, difficulties in the blasting excavation of anchors, and the extremely high risk of construction. Therefore, comprehensive risk control measures using the methods of hierarchical excavation and minimum charge blasting are put forward. After the measures were verified to be feasible through finite element simulation, it was successfully applied to actual construction. In addition, this paper proposes using fiber concrete to reinforce slope retaining walls, and simulates the reinforced effect based on the research above. The results indicate that the risk control scheme is reasonable, which not only ensures the construction process but also guarantees the stability of the slope and unstable rock body. At the same time, the slope is reinforced with fiber concrete, which effectively decreases the protection wall thickness. Finally, the article can provide a valuable reference for similar engineering projects around the world.

7.
Int J Mol Sci ; 23(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36362205

RESUMO

The grape (Vitis vinifera L.) not only has a long history of cultivation, but also has rich nutritional value and high economic value. However, grapes often face many threats in the growth process. For example, low temperature and salt stress restrict the growth status, yield, and geographical distribution of grapes. WRKY, as one of the largest transcription factor (TF) families in plants, participates in the response of plants to stress. VvWRKY28, a new zinc finger type transcriptional regulator gene, was isolated from Beichun (V. vinifera × V.amurensis) in this study. From the subcellular localization results, it can be concluded that VvWRKY28 was localized in the nucleus. The expression of VvWRKY28 was enriched in leaves (young and mature leaves), and cold and high salt conditions can induce high expression of VvWRKY28. After being transferred into Arabidopsis, VvWRKY28 greatly improved the tolerance of Arabidopsis to low temperature and high salt and also changed many physiological and biochemical indicators of transgenic Arabidopsis to cope with cold and high salt stimulation. The content of malondialdehyde (MDA) was decreased, but for chlorophyll and proline, their content increased, and the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were improved. In addition, under cold stress, binding with cis-acting elements promotes the expression of downstream genes related to cold stress (RAB18, COR15A, ERD10, PIF4, COR47, and ICS1). Moreover, it also plays an active role in regulating the expression of genes related to salt stress (NCED3, SnRK2.4, CAT2, SOD1, SOS2, and P5CS1) under salt stress. Therefore, these results provide evidence that VvWRKY28 may play a role in the process of plant cold and salt stress tolerance.


Assuntos
Arabidopsis , Vitis , Arabidopsis/metabolismo , Vitis/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Estresse Fisiológico/genética , Secas
9.
Sci Rep ; 12(1): 16054, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-36163228

RESUMO

It is a multi-criteria decision issue to conduct a risk assessment of the tunnel. In this paper, a tunnel collapse risk assessment model based on the improved theory of quantification III and the fuzzy comprehensive evaluation method is proposed. According to the geological conditions and the construction disturbance classification method, the evaluation factors are selected, and the tunnel collapse risk level is divided into 5 levels according to the principle of maximum membership degree. The three groups of scores with the largest correlation ratio are calculated by the theory of quantification III to form the X, Y, and Z axes of the spatial coordinate system, The spatial distance of each evaluation factor is optimized by the Kendall correlation coefficient combined with the empirical formula, so that it can be used to judge the probability of the occurrence of the evaluation factor; taking the coupling of the objective entropy weight method (EW) and the subjective analytic hierarchy process (AHP) as the weight. Finally, the fuzzy comprehensive evaluation method is used to determine the possibility classification of tunnel collapse. Taking the Ka-Shuang water diversion tunnel as a case study, the comparison between the evaluation results of 10 tunnel samples and the status quo of the actual engineering area verifies the reliability of the method.


Assuntos
Monitoramento Ambiental , Lógica Fuzzy , Processo de Hierarquia Analítica , Monitoramento Ambiental/métodos , Reprodutibilidade dos Testes , Medição de Risco/métodos , Água
10.
Avian Dis ; 66(1): 1, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35092235

RESUMO

This article has been withdrawn at the request of the authors. The Publisher apologizes for any inconvenience this may cause.

11.
Mol Neurobiol ; 59(2): 762-777, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34773219

RESUMO

AMPA receptor mediate most fast excitatory synaptic transmission and play a key role in synaptic plasticity in the central nervous system (CNS) by trafficking and targeting of its subunits to individual postsynaptic membrane. Collapsing response mediator protein 2 (CRMP2), an intracellular phospho-protein, has been reported to promote the maturation of the dendritic spine and transfer AMPA receptors to the membrane. However, our knowledge about the molecular mechanisms of CRMP2 regulating AMPA receptors trafficking is limited. Here, we reported that CRMP2 promoted the surface expression of AMPA receptor GluA1 subunit in cultured hippocampal neurons and in HEK293T cells expressing GluA1 subunits. Furthermore, we found that CRMP2 interacted with GluA1, and their interaction was inhibited by CRMP2 phosphorylation at ser522. Moreover, our results showed that phosphorylation of CRMP2 at ser522 by cyclin-dependent kinase 5 (Cdk5) decreased the fluorescence intensity of surface GluA1 and the amplitude and frequency of miniature excitatory synaptic currents (mEPSCs) in cultured hippocampal neurons, indicating a reduction levels and synaptic function of AMPA receptors. Taken together, our data demonstrated that phosphorylation of CRMP2 by Cdk5 is important for AMPA receptor surface delivery in hippocampal neurons.


Assuntos
Quinase 5 Dependente de Ciclina , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas do Tecido Nervoso , Receptores de AMPA , Quinase 5 Dependente de Ciclina/metabolismo , Células HEK293 , Hipocampo/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/química , Proteínas do Tecido Nervoso/química , Fosforilação , Receptores de AMPA/metabolismo , Transmissão Sináptica
12.
R Soc Open Sci ; 8(11): 211266, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34737881

RESUMO

Assistive devices are used to reduce human effort during locomotion with increasing success. More assistance strategies are worth exploring, so we aimed to design a lightweight biarticular device with well-chosen parameters to reduce muscle effort. Based on the experience of previous success, we designed an exotendon to assist in swing leg deceleration. Then we conducted experiments to test the performance of the exotendon with different spring stiffness during walking. With the assistance of the exotendon, peak activation of semitendinosus decreased, with the largest reduction of 12.3% achieved with the highest spring stiffness (p = 0.004). The peak activations of other measured muscles were not significantly different (p = 0.15-0.92). The biological hip extension and knee flexion moments likewise significantly decreased with the spring stiffness (p < 0.01). The joint angle was altered during the assisted phases with decreased hip flexion and knee extension. Meanwhile, the step frequency and the step length were also altered, while the step width remained unaffected. Gait variability changed only in the frontal plane, exhibiting lower step width variability. We conclude that passive devices assisting hip extension and knee flexion can significantly reduce the burden on the hamstring muscles, while the kinematics is easily altered.

13.
Arch Virol ; 166(11): 3105-3116, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34482448

RESUMO

Several outbreaks of duck hepatitis A virus type 1 (DHAV-1), which were characterized by yellow coloration and hemorrhage in pancreatic tissues, have occurred in China. The causative agent is called pancreatitis-associated DHAV-1. The mechanisms involved in pancreatitis-associated DHAV-1 infection are still unclear. Transcriptome analysis of duck pancreas infected with classical-type DHAV-1 and pancreatitis-associated DHAV-1 was carried out. Deep sequencing with Illumina-Solexa resulted in a total of 53.9 Gb of clean data from the cDNA library of the pancreas, and a total of 29,597 unigenes with an average length of 993.43 bp were generated by de novo sequence assembly. The expression levels of D-3-phosphoglycerate dehydrogenase, phosphoserine aminotransferase, and phosphoserine phosphatase, which are involved in glycine, serine, and threonine metabolism pathways, were significantly downregulated in ducks infected with pancreatitis-associated DHAV-1 compared with those infected with classical-type DHAV-1. These findings provide information regarding differences in expression levels of metabolism-associated genes between ducks infected with pancreatitis-associated DHAV-1 and those infected with classical-type DHAV-1, indicating that intensive metabolism disorders may contribute to the different phenotypes of DHAV-1-infection.


Assuntos
Vírus da Hepatite do Pato/patogenicidade , Hepatite Viral Animal/virologia , Interações Hospedeiro-Patógeno/genética , Infecções por Picornaviridae/veterinária , Doenças das Aves Domésticas/virologia , Aminoácidos/genética , Aminoácidos/metabolismo , Animais , Patos/virologia , Expressão Gênica , Hepatite Viral Animal/genética , Hepatite Viral Animal/metabolismo , Hepatite Viral Animal/patologia , Pâncreas/citologia , Pâncreas/patologia , Pâncreas/virologia , Pancreatite/patologia , Pancreatite/virologia , Infecções por Picornaviridae/metabolismo , Infecções por Picornaviridae/patologia , Infecções por Picornaviridae/virologia , Doenças das Aves Domésticas/genética , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/patologia , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA
14.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(7): 667-670, 2021 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-34247374

RESUMO

OBJECTIVE: To explore the genetic basis for a fetus with cerebellar dysplasia and widened lateral ventricles. METHODS: The couple have elected induced abortion after careful counseling. Skin tissue sample from the abortus and peripheral venous blood samples from both parents were collected for the extraction of genomic DNA, which was then subjected to whole exome sequencing. Candidate variant was verified by Sanger sequencing. RESULTS: Prenatal ultrasonography showed increased nuchal translucency (0.4 cm) and widened lateral ventricles. Magnetic resonance imaging revealed infratentorial brain dysplasia. By DNA sequencing, the fetus was found to carry compound heterozygous variants c.1A>G and c.1564G>A of the RARS2 gene, which were inherited from its father and mother, respectively. Among these, c.1A>G was known to be pathogenic, but the pathogenicity of c.1564G>A was unreported previously. Based on the American College of Medical Genetics and Genomics guidelines, the c.1564G>A variant of RARS2 gene was predicted to be likely pathogenic(PM2+PM3+PP3+PP4). CONCLUSION: The compound heterozygous variants c.1A>G and c.1564G>A of RARS2 gene contributed to the fetus suffering from pontocerebellar hypoplasia type 6, which expanded variant spectrum of RARS2 gene.


Assuntos
Atrofias Olivopontocerebelares , Feminino , Feto , Genômica , Humanos , Mutação , Gravidez , Sequenciamento do Exoma
15.
Front Bioeng Biotechnol ; 9: 793746, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35127668

RESUMO

A proper movement categorization reduces the complexity of understanding or reproducing human movements in fields such as physiology, rehabilitation, and robotics, through partitioning a wide variety of human movements into representative sub-motion groups. However, how to establish a categorization (especially a quantitative categorization) for various human lower limb movements is rarely investigated in literature and remains challenging due to the diversity and complexity of the lower limb movements (diverse gait modes and interaction styles with the environment). Here we present a quantitative categorization for the various lower limb movements. To this end, a similarity measure between movements was first built based on limb kinematic synergies that provide a unified and physiologically meaningful framework for evaluating the similarities among different types of movements. Then, a categorization was established via hierarchical cluster analysis for thirty-four lower limb movements, including walking, running, hopping, sitting-down-standing-up, and turning in different environmental conditions. According to the movement similarities, the various movements could be divided into three distinct clusters (cluster 1: walking, running, and sitting-down-standing-up; cluster 2: hopping; cluster 3: turning). In each cluster, cluster-specific movement synergies were required. Besides the uniqueness of each cluster, similarities were also found among part of the synergies employed by these different clusters, perhaps related to common behavioral goals in these clusters. The mix of synergies shared across the clusters and synergies for specific clusters thus suggests the coexistence of the conservation and augmentation of the kinematic synergies underlying the construction of the diverse and complex motor behaviors. Overall, the categorization presented here yields a quantitative and hierarchical representation of the various lower limb movements, which can serve as a basis for the understanding of the formation mechanisms of human locomotion and motor function assessment and reproduction in related fields.

16.
CNS Neurol Disord Drug Targets ; 20(3): 249-265, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-33109053

RESUMO

AIMS: Our work aims to revealing the underlying microtubule mechanism of neurites outgrowth during neuronal development and also proposes a feasible intervention pathway for reconstructing neural network connections after nerve injury. BACKGROUND: Microtubule polymerization and severing form the basis for neurite outgrowth and branch formation. However, the mechanisms that underlie the dynamic instability of microtubules are unclear. Here, we showed that neurite outgrowth mediated by collapsing response mediator protein 2 (CRMP2) can be enhanced by spastin, which had an effect on the severing of microtubule cytoskeleton. OBJECTIVE: To explore whether neurite outgrowth was mediated by coordination of CRMP2 and spastin. METHODS: Hippocampal neurons were cultured in vitro in 24-well culture plates for 4 days before being used to perform the transfection. Calcium phosphate was used to transfect the CRMP2 and spastin constructs and their control into the neurons. An interaction between CRMP2 and spastin was examined by using pull down, CoIP and immunofluorescence colocalization assays. And immunostaining was also performed to determine the morphology of neurites. RESULTS: We first demonstrated that CRMP2 interacted with spastin to promote neurite outgrowth and branch formation. Then our results identified that CRMP2 interacted with the microtubule- binding domain of spastin via its C-terminus, and deleting these binding sites inhibited neurite outgrowth and branch formation. In addition, we confirmed one phosphorylation site at S210 of spastin in hippocampal neurons. Spastin phosphorylation at S210 failed to alter the binding affinity of CRMP2 but inhibited its binding to microtubules. Further study showed that phosphorylation spastin at S210 inhibited the neurite outgrowth induced by CRMP2 and spastin interaction through downregulation of microtubule-severing activity. CONCLUSION: Taken together, our data demonstrated that both CRMP2 and spastin interaction and the microtubule-severing activity of spastin were required for neurite outgrowth and branch formation.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Microtúbulos/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Crescimento Neuronal/efeitos dos fármacos , Espastina/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Humanos , Proteínas Associadas aos Microtúbulos , Neuritos/efeitos dos fármacos , Fosforilação
17.
J Glob Antimicrob Resist ; 23: 251-255, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33045440

RESUMO

OBJECTIVES: The aim of this study was to investigate the presence and genetic environment of the multiresistance gene cfr gene in Pasteurella multocida of avian origin from China. METHODS: A total of 113 P. multocida isolates were collected from sick poultries (ducks, chickens and geese) from 2003 to 2016 in Southern China and were screened for the presence of the cfr gene by PCR. The cfr-carrying P. multocida strains were subjected to antimicrobial susceptibility testing, S1 nuclease PFGE and Southern blot hybridisation, conjugative transfer and analysis of genetic environment of the cfr gene. RESULTS: Among 113 P. multocida isolates, strains FJ6671 and FJ6683 from Muscovy duck harboured the cfr gene and presented a multiresistant phenotype. The cfr gene in the two strains was located on an ∼40-kb conjugative plasmid in different genetic environments, including ISApl12-cfr-IS26 and IS26-cfr-IS256. CONCLUSIONS: These results demonstrate plasmid-carried cfr in P. multocida and suggest that transposition and homologous recombination mediated by IS26, ISApl1 and IS256 might have played an important role in transfer of the cfr gene in P. multocida. To the best of our knowledge, this is the first report of the cfr gene in P. multocida. Active and ongoing surveillance of cfr in P. multocida is urgently warranted.


Assuntos
Pasteurella multocida , Animais , Galinhas , China , Testes de Sensibilidade Microbiana , Pasteurella multocida/genética , Plasmídeos/genética
18.
Res Vet Sci ; 132: 221-228, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32615343

RESUMO

In this study, a Streptococcus strainnamed FJ1804, was isolated from a blood sample collected from a dead Macaca mulatta in China and, was subsequently classified as Streptococcus equi subsp. ruminatorum (S.e. ruminatorum) through 16S rRNA gene sequence analysis. After whole genome sequencing and analysis, an M-like protein encoding gene that encodes an SrM protein that is homologous to the crucial S.e. zooepidemicus crucial virulence factor SzP, was identified in the genome of FJ1804. To determinethe function of SrM in this bacterium, a strain deleted of srm as well as a complement strain were constructed. The results of in vitro cell adherence, invasion and phagocytosis assays and in vivo animal challenge and histopathology showed that the anti-phagocytosis was decreased and the adherence rate was increased in the srm deletion strain, whereas the invasion rate, pathological features and LD50 values inboth zebrafish and BALB/c mice model showed no difference compared to that observed for the WT strain. To the best of our knowledge, this is first of an infection caused by S.e. ruminatorum, which is a newly identified zoonotic pathogen, in Macaca mulatta, and our data suggest that, compared with other S.e. zooepidemicus strains, the SzP homologous protein is not crucial to the virulence of this bacterium.


Assuntos
Proteínas de Bactérias/genética , Macaca mulatta , Doenças dos Macacos/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus/genética , Streptococcus/patogenicidade , Animais , Aderência Bacteriana , Proteínas de Bactérias/metabolismo , China , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Filogenia , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Organismos Livres de Patógenos Específicos , Infecções Estreptocócicas/microbiologia , Virulência
19.
Mol Med Rep ; 21(6): 2367-2374, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32236575

RESUMO

It is commonly known that the specific function of a given ATPase associated with diverse cellular activities protein (i.e., a member of the AAA superfamily of proteins) depends primarily on its subcellular location. The microtubule­severing protein fidgetin (Fign) possesses a nuclear localization signal (NLS) that facilitates its translocation to the nucleus, where its assembly is finalized; here, Fign contributes to the regulation of microtubule configuration by cutting and trimming microtubule polymers. In the present study, Fign was found to be a nuclear protein, whose N­terminal sequence (SSLKRKAFYM; residues 314­323) acts as an NLS. Following substitution (KR to NN; 317­318) or deletion (NT; 314­323) mutations within the NLS, Fign, which is predominantly expressed in the nucleus, was found to reside in the cytoplasm of transfected cells. Furthermore, Fign was found to have an essential role in microtubule severing by preferentially targeting highly­tyrosinated microtubules (tyr­MTs). Mutation of the Fign NLS did not affect its microtubule­severing function or the cleavage of tyr­MTs, but did affect the cellular distribution of the Fign protein itself. Taken altogether, an NLS for Fign was identified, and it was demonstrated that the basic amino acids K317 and R318 are necessary for regulating its entry into the nucleus, whereas an increase in Fign in the cytosol due to mutations of the NLS did not affect its cleavage function.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/metabolismo , Núcleo Celular/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Sinais de Localização Nuclear/metabolismo , Adenosina Trifosfatases/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Citoplasma/metabolismo , Células HEK293 , Células HeLa , Humanos , Sinais de Localização Nuclear/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Deleção de Sequência , Transfecção
20.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(2): 139-141, 2020 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-32034739

RESUMO

OBJECTIVE: To detect potential variant in a male fetus suspected for Ectrodactyly, Ectodermal dysplasia, Cleft lip/palate (EEC) syndrome. METHODS: Peripheral blood samples of the fetus and his parents were collected for the extraction of DNA. Whole-exome sequencing was carried out to detect potential variants. Suspected variants were verified by Sanger sequencing. RESULTS: The fetus was found to carry a heterozygous c.673C>T missense variant of the Tp63 gene, which was known to underlie split-hand/split-foot malformation. The same variant was not found in either parents. CONCLUSION: The heterozygous c.673C>T missense variant of the Tp63 gene probably underlies the EEC syndrome in the fetus. Above finding also expanded the phenotypic spectrum for this variant.


Assuntos
Fenda Labial , Fissura Palatina , Displasia Ectodérmica , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Fenda Labial/genética , Fissura Palatina/genética , Displasia Ectodérmica/genética , Humanos , Deformidades Congênitas dos Membros , Masculino , Sequenciamento do Exoma
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