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1.
Nature ; 603(7901): 421-426, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35296842

RESUMO

Engineering quantum states through light-matter interaction has created a paradigm in condensed-matter physics. A representative example is the Floquet-Bloch state, which is generated by time-periodically driving the Bloch wavefunctions in crystals. Previous attempts to realize such states in condensed-matter systems have been limited by the transient nature of the Floquet states produced by optical pulses1-3, which masks the universal properties of non-equilibrium physics. Here we report the generation of steady Floquet-Andreev states in graphene Josephson junctions by continuous microwave application and direct measurement of their spectra by superconducting tunnelling spectroscopy. We present quantitative analysis of the spectral characteristics of the Floquet-Andreev states while varying the phase difference of the superconductors, the temperature, the microwave frequency and the power. The oscillations of the Floquet-Andreev-state spectrum with phase difference agreed with our theoretical calculations. Moreover, we confirmed the steady nature of the Floquet-Andreev states by establishing a sum rule of tunnelling conductance4, and analysed the spectral density of Floquet states depending on Floquet interaction strength. This study provides a basis for understanding and engineering non-equilibrium quantum states in nanodevices.

2.
Ann Neurol ; 93(2): 384-397, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36093572

RESUMO

OBJECTIVE: To examine the associations between the allergic triad (asthma, allergic rhinitis, atopic dermatitis) and risk of dementia. METHODS: Participants comprised 6,785,948 adults aged ≥40 years who participated in a national health examination in 2009 without any history of dementia before baseline. From 2009 to 2017, we prospectively investigated the associations between physician-diagnosed allergic diseases and risk of incident dementia (all-cause, Alzheimer's disease [AD], vascular dementia [VaD]) ascertained using national health insurance claims data. RESULTS: During 8.1 years of follow-up, 260,705 dementia cases (195,739 AD, 32,789 VaD) were identified. Allergic diseases were positively associated with dementia risk. Compared with individuals without allergic diseases, multivariable hazard ratios (HRs) of all-cause dementia were 1.20 (95% confidence interval [CI] 1.19-1.22) in those with asthma, 1.10 (95% CI 1.09-1.12) with allergic rhinitis, 1.16 (95% CI 1.11-1.21) with atopic dermatitis, and 1.13 (95% CI 1.12-1.14) with any of these allergies. Similarly, individuals with any of the allergic triad had a higher risk of AD (HR 1.16, 95% CI 1.14-1.17) and VaD (HR 1.04; 95% CI 1.01-1.06) than those without any allergic disease. As the number of comorbid allergic diseases increased, the risk of dementia increased linearly (Ptrend ≤ 0.002). Compared with individuals without allergies, those with all three allergic diseases had substantially increased risk of all-cause dementia (HR 1.54, 95% CI 1.35-1.75), AD (HR 1.46; 95% CI 1.25-1.70), and VaD (HR 1.99, 95% CI 1.44-2.75). INTERPRETATION: Asthma, allergic rhinitis, and atopic dermatitis were significantly associated with increased risk of all-cause dementia and subtypes, with dose-effect relationships with the severity of allergic diseases. ANN NEUROL 2023;93:384-397.


Assuntos
Doença de Alzheimer , Asma , Demência Vascular , Dermatite Atópica , Rinite Alérgica , Adulto , Humanos , Doença de Alzheimer/epidemiologia , Asma/epidemiologia , Rinite Alérgica/epidemiologia , Fatores de Risco
3.
Vet Res ; 55(1): 74, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38863015

RESUMO

Bovine coronavirus (BCoV) is a pneumoenteric virus that can infect the digestive and respiratory tracts of cattle, resulting in economic losses. Despite its significance, information regarding BCoV pathogenesis is limited. Hence, we investigated clinical signs, patterns of viral shedding, changes in antibody abundance, and cytokine/chemokine production in calves inoculated with BCoV via intranasal and oral. Six clinically healthy Korean native calves (< 30 days old), initially negative for BCoV, were divided into intranasal and oral groups and monitored for 15 days post-infection (dpi). BCoV-infected calves exhibited clinical signs such as nasal discharge and diarrhea, starting at 3 dpi and recovering by 12 dpi, with nasal discharge being the most common symptoms. Viral RNA was detected in nasal and fecal samples from all infected calves. Nasal shedding occurred before fecal shedding regardless of the inoculation route; however, fecal shedding persisted longer. Although the number of partitions was very few, viral RNA was identified in the blood of two calves in the oral group at 7 dpi and 9 dpi using digital RT-PCR analysis. The effectiveness of maternal antibodies in preventing viral replication and shedding appeared limited. Our results showed interleukin (IL)-8 as the most common and highly induced chemokine. During BCoV infection, the levels of IL-8, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1ß were significantly affected, suggesting that these emerge as potential and reliable biomarkers for predicting BCoV infection. This study underscores the importance of BCoV as a major pathogen causing diarrhea and respiratory disease.


Assuntos
Doenças dos Bovinos , Infecções por Coronavirus , Coronavirus Bovino , Eliminação de Partículas Virais , Animais , Bovinos , Doenças dos Bovinos/virologia , Doenças dos Bovinos/imunologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Infecções por Coronavirus/imunologia , República da Coreia , Fezes/virologia , RNA Viral/análise , Anticorpos Antivirais/sangue , Citocinas/metabolismo , Citocinas/genética , Masculino
4.
BMC Neurol ; 24(1): 18, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178033

RESUMO

BACKGROUND: Inflammation is a major pathological mechanism underlying cerebrovascular disease. Recently, a new inflammatory marker based on the ratio between monocyte count and high-density lipoprotein (HDL) cholesterol has been proposed. In this study, we evaluated the relationship between monocyte-to-HDL cholesterol ratio (MHR) and cerebral small vessel disease (cSVD) lesions in health check-up participants. METHODS: This study was a retrospective cross-sectional study based on a registry that prospectively collected health check-up participants between 2006 and 2013. Three cSVD subtypes were measured on brain magnetic resonance imaging. White matter hyperintensity (WMH) volume, and lacunes and cerebral microbleeds (CMBs) were quantitatively and qualitatively measured, respectively. The MHR was calculated according to the following formula: MHR = monocyte counts (× 103/µL) / HDL cholesterol (mmol/L). RESULTS: In total, 3,144 participants were evaluated (mean age: 56 years, male sex: 53.9%). In multivariable analyzes adjusting for confounders, MHR was significantly associated with WMH volume [ß = 0.099, 95% confidence interval (CI) = 0.025 to 0.174], lacune [adjusted odds ratio (aOR) = 1.43, 95% CI = 1.07-1.91], and CMB (aOR = 1.51, 95% CI = 1.03-2.19). In addition, MHR showed a positive quantitative relationship with cSVD burden across all three subtypes: WMH (P < 0.001), lacunes (P < 0.001), and CMBs (P < 0.001). CONCLUSIONS: High MHR was closely associated with cSVD in health check-up participants. Because these associations appear across all cSVD subtypes, inflammation appears to be a major pathological mechanism in the development of various cSVDs.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Monócitos , Humanos , Masculino , Pessoa de Meia-Idade , HDL-Colesterol , Estudos Retrospectivos , Estudos Transversais , Imageamento por Ressonância Magnética , Inflamação/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/complicações
6.
BMC Vet Res ; 20(1): 121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532391

RESUMO

BACKGROUND: Hemotropic mycoplasmas or hemoplasmas are bacteria that attach to the erythrocyte surface and cause bovine hemoplasmosis. Two species, Mycoplasma wenyonii and Candidatus Mycoplasma haemobos, have been identified and shown to be distributed worldwide. However, there is currently no information available on hemoplasmas in cattle in the Republic of Korea. The aim of this study was to investigate the presence of hemoplasmas in Korean native cattle and to evaluate the association between hemoplasma infection and anemia. METHODS: One farm was selected, at which blood samples were collected from 104 Korean native cattle [grazing cattle (n = 89) and housed cattle (n = 15)]. Hemoplasmas were detected via polymerase chain reaction analysis and complete blood counts were also performed. RESULTS: The overall prevalence of hemoplasmas was 34% (35/104); 20.2% (21/104) for M. wenyonii, 3.8% (4/104) for C. M. haemobos, and 9.6% (10/104) for co-infection. Candidatus Mycoplasma haemobos was detected only in grazing cattle. Of red blood cell (RBC) parameters, C. M. haemobos-infected cattle had lower RBC and hematocrit, and higher mean cell volume than hemoplasma-negative cattle, although none of these differences were statistically significant. This is the first study to report the occurrence of M. wenyonii and C. M. haemobos. Mycoplasma wenyonii is more prevalent than C. M. haemobos in Korean native cattle. The results did not show an association between hemoplasma infection and anemia. CONCLUSIONS: Considering the infection rate of hemoplasmas shown in this study, further studies, such as on the pathogenicity and clinical significance of hemoplasmas are necessary.


Assuntos
Anemia , Doenças dos Bovinos , Infecções por Mycoplasma , Mycoplasma , Bovinos , Animais , Infecções por Mycoplasma/veterinária , Doenças dos Bovinos/epidemiologia , Mycoplasma/genética , Anemia/veterinária , RNA Ribossômico 16S
7.
Magn Reson Med ; 89(4): 1456-1468, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36420869

RESUMO

PURPOSE: To develop a new approach to 3D gradient echo-based anatomical imaging of the neonatal brain with a substantially shorter scan time than standard 3D fast spin echo (FSE) methods, while maintaining a high SNR. METHODS: T2 -prepration was employed immediately prior to image acquisition of 3D balanced steady-state free precession (bSSFP) with a single trajectory of center-out k-space view ordering, which requires no magnetization recovery time between imaging segments during the scan. This approach was compared with 3D FSE, 2D single-shot FSE, and product 3D bSSFP imaging in numerical simulations, plus phantom and in vivo experiments. RESULTS: T2 -prepared 3D bSSFP generated image contrast of gray matter, white matter, and CSF very similar to that of reference T2 -weighted imaging methods, without major image artifacts. Scan time of T2 -prepared 3D bSSFP was remarkably shorter compared to 3D FSE, whereas SNR was comparable to that of 3D FSE and higher than that of 2D single-shot FSE. Specific absorption rate of T2 -prepared 3D bSSFP remained within the safety limit. Determining an optimal imaging flip angle of T2 -prepared 3D bSSFP was critical to minimizing blurring of images. CONCLUSION: T2 -prepared 3D bSSFP offers an alternative method for anatomical imaging of the neonatal brain with dramatically reduced scan time compared to standard 3D FSE and higher SNR than 2D single-shot FSE.


Assuntos
Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Aumento da Imagem/métodos , Encéfalo/diagnóstico por imagem
8.
Nucleic Acids Res ; 49(19): 11312-11322, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34554247

RESUMO

There have been many engineered Cas9 variants that were developed to minimize unintended cleavage of off-target DNAs, but detailed mechanism for the way they regulate the target specificity through DNA:RNA heteroduplexation remains poorly understood. We used single-molecule FRET assay to follow the dynamics of DNA:RNA heteroduplexation for various engineered Cas9 variants with respect to on-target and off-target DNAs. Just like wild-type Cas9, these engineered Cas9 variants exhibit a strong correlation between their conformational structure and nuclease activity. Compared with wild-type Cas9, the fraction of the cleavage-competent state dropped more rapidly with increasing base-pair mismatch, which gives rise to their enhanced target specificity. We proposed a reaction model to quantitatively analyze the degree of off-target discrimination during the successive process of R-loop expansion. We found that the critical specificity enhancement step is activated during DNA:RNA heteroduplexation for evoCas9 and HypaCas9, while it occurs in the post-heteroduplexation stage for Cas9-HF1, eCas9, and Sniper-Cas9. This study sheds new light on the conformational dynamics behind the target specificity of Cas9, which will help strengthen its rational designing principles in the future.


Assuntos
Proteína 9 Associada à CRISPR/genética , DNA/genética , RNA/genética , Imagem Individual de Molécula/métodos , Pareamento de Bases , Proteína 9 Associada à CRISPR/química , Proteína 9 Associada à CRISPR/metabolismo , Clonagem Molecular , DNA/química , DNA/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Transferência Ressonante de Energia de Fluorescência , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Células HEK293 , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Modelos Moleculares , Mutação , Hibridização de Ácido Nucleico , Conformação Proteica , Engenharia de Proteínas/métodos , RNA/química , RNA/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
Sensors (Basel) ; 23(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37112505

RESUMO

Various edge collaboration schemes that rely on reinforcement learning (RL) have been proposed to improve the quality of experience (QoE). Deep RL (DRL) maximizes cumulative rewards through large-scale exploration and exploitation. However, the existing DRL schemes do not consider the temporal states using a fully connected layer. Moreover, they learn the offloading policy regardless of the importance of experience. They also do not learn enough because of their limited experiences in distributed environments. To solve these problems, we proposed a distributed DRL-based computation offloading scheme for improving the QoE in edge computing environments. The proposed scheme selects the offloading target by modeling the task service time and load balance. We implemented three methods to improve the learning performance. Firstly, the DRL scheme used the least absolute shrinkage and selection operator (LASSO) regression and attention layer to consider the temporal states. Secondly, we learned the optimal policy based on the importance of experience using the TD error and loss of the critic network. Finally, we adaptively shared the experience between agents, based on the strategy gradient, to solve the data sparsity problem. The simulation results showed that the proposed scheme achieved lower variation and higher rewards than the existing schemes.

10.
Sensors (Basel) ; 23(12)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37420758

RESUMO

The emergence of the global coronavirus pandemic in 2019 (COVID-19 disease) created a need for remote methods to detect and continuously monitor patients with infectious respiratory diseases. Many different devices, including thermometers, pulse oximeters, smartwatches, and rings, were proposed to monitor the symptoms of infected individuals at home. However, these consumer-grade devices are typically not capable of automated monitoring during both day and night. This study aims to develop a method to classify and monitor breathing patterns in real-time using tissue hemodynamic responses and a deep convolutional neural network (CNN)-based classification algorithm. Tissue hemodynamic responses at the sternal manubrium were collected in 21 healthy volunteers using a wearable near-infrared spectroscopy (NIRS) device during three different breathing conditions. We developed a deep CNN-based classification algorithm to classify and monitor breathing patterns in real time. The classification method was designed by improving and modifying the pre-activation residual network (Pre-ResNet) previously developed to classify two-dimensional (2D) images. Three different one-dimensional CNN (1D-CNN) classification models based on Pre-ResNet were developed. By using these models, we were able to obtain an average classification accuracy of 88.79% (without Stage 1 (data size reducing convolutional layer)), 90.58% (with 1 × 3 Stage 1), and 91.77% (with 1 × 5 Stage 1).


Assuntos
COVID-19 , Doenças Transmissíveis , Aprendizado Profundo , Humanos , COVID-19/diagnóstico , Redes Neurais de Computação , Respiração
11.
Int J Mol Sci ; 24(20)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37894931

RESUMO

Bone morphogenetic proteins (BMPs) have tremendous therapeutic potential regarding the treatment of bone and musculoskeletal disorders due to their osteo-inductive ability. More than twenty BMPs have been identified in the human body with various functions, such as embryonic development, skeleton genesis, hematopoiesis, and neurogenesis. BMPs can induce the differentiation of MSCs into the osteoblast lineage and promote the proliferation of osteoblasts and chondrocytes. BMP signaling is also involved in tissue remodeling and regeneration processes to maintain homeostasis in adults. In particular, growth factors, such as BMP-2 and BMP-7, have already been approved and are being used as treatments, but it is unclear as to whether they are the most potent BMPs that induce bone formation. According to recent studies, BMP-9 is known to be the most potent inducer of the osteogenic differentiation of mesenchymal stem cells, both in vitro and in vivo. However, its exact role in the skeletal system is still unclear. In addition, research results suggest that the molecular mechanism of BMP-9-mediated bone formation is also different from the previously known BMP family, suggesting that research on signaling pathways related to BMP-9-mediated bone formation is actively being conducted. In this study, we performed a phosphorylation array to investigate the signaling mechanism of BMP-9 compared with BMP-2, another influential bone-forming growth factor, and we compared the downstream signaling system. We present a mechanism for the signal transduction of BMP-9, focusing on the previously known pathway and the p53 factor, which is relatively upregulated compared with BMP-2.


Assuntos
Fator 2 de Diferenciação de Crescimento , Osteogênese , Humanos , Proteína Morfogenética Óssea 2/farmacologia , Proteína Morfogenética Óssea 2/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular , Fator 2 de Diferenciação de Crescimento/metabolismo , Osteoblastos/metabolismo , Periósteo/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo
12.
Vet Med (Praha) ; 68(9): 375-383, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37981941

RESUMO

Jejunal haemorrhage syndrome (JHS) is a sporadic and fatal enterotoxaemic disease in dairy cows associated with acute development and poor prognosis despite treatment. A 5-year-old Holstein cow with no reported pregnancy, three calving numbers, and 303 days in milk presented with hypothermia, discomfort, and inappetence. Anaemia, dehydration, faeces with blood clots, and absence of rumen and bowel movements were observed. We identified the presence of neutrophilia, hyperglycaemia, hypoproteinaemia, azotaemia, hyperlactatemia, hypocalcaemia, hypermagnesemia, hypokalaemia, and hypochloraemia through blood analyses. Necropsy and histopathologic examination revealed a dilated bluish-purple jejunum, blood clots within the jejunum, neutrophil infiltration into the submucosa of the jejunum, and vascular necrosis. Retrospective examination revealed extraordinary patterns of rumination time, activity, rumen mobility, and rumen temperature using biosensors and decreased milk yield. The abnormalities in the affected cow were detected before recognition by farm workers. To the best of our knowledge, this is the first report to examine data from biosensors in a cow with JHS. Our findings suggest that using biometric data may help understand the development of JHS.

13.
Ann Surg Oncol ; 29(13): 8185-8193, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36070112

RESUMO

BACKGROUND: We seek to explore the ability of computed tomography (CT)-based radiomics coupled with artificial intelligence (AI) to predict early recurrence (< 2 years after surgery) in patients with clinical stage 0-IA non-small cell lung cancer (c-stage 0-IA NSCLC). PATIENTS AND METHODS: Data of 642 patients were collected for early recurrence and assigned to the derivation and validation cohorts at a ratio of 2:1. Using the AI software Beta Version (Fujifilm Corporation, Japan), 39 AI imaging factors, including 17 factors from the AI ground-glass nodule analysis and 22 radiomic features from nodule characterization analysis, were extracted. RESULTS: Multivariate analysis showed that male sex (p = 0.016), solid part size (p < 0.001), CT value standard deviation (p = 0.038), solid part volume ratio (p = 0.016), and bronchus translucency (p = 0.007) were associated with recurrence-free survival (RFS). Receiver operating characteristics analysis showed that the area under the curve and optimal cutoff values relevant to recurrence were 0.707 and 1.49 cm for solid part size, and 0.710 and 22.9% for solid part volume ratio, respectively. The 5-year RFS rates for patients in the validation set with solid part size ≤ 1.49 cm and > 1.49 cm were 92.2% and 70.4% (p < 0.001), whereas those for patients with solid part volume ratios ≤ 22.9% and > 22.9% were 97.8% and 71.7% (p < 0.001), respectively. CONCLUSIONS: CT-based radiomics coupled with AI contributes to the noninvasive prediction of early recurrence in patients with c-stage 0-IA NSCLC.


Assuntos
Carcinoma in Situ , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Masculino , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/patologia , Inteligência Artificial , Estadiamento de Neoplasias , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos
14.
Eur Radiol ; 32(12): 8122-8130, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35771246

RESUMO

OBJECTIVES: To investigate the effect of the phantom-based correction method for standardizing myocardial native T1 and extracellular volume fraction (ECV) in healthy subjects. METHODS: Seventy-one healthy asymptomatic adult (≥ 20 years) volunteers of five different age groups (34 men and 37 women, 45.5 ± 15.5 years) were prospectively enrolled in three academic hospitals. Cardiac MRI including Modified Look - Locker Inversion recovery T1 mapping sequence was performed using a 3-Tesla system with a different type of scanner for each hospital. Native T1 and ECV were measured in the short-axis T1 map and analyzed for mean values of the 16 entire segments. The myocardial T1 value of each subject was corrected based on the site-specific equation derived from the T1 Mapping and ECV Standardization phantom. The global native T1 and ECV were compared between institutions before and after phantom-based correction, and the variation in native T1 and ECV among institutions was assessed using a coefficient of variation (CoV). RESULTS: The global native T1 value significantly differed between the institutions (1198.7 ± 32.1 ms, institution A; 1217.7 ± 39.9 ms, institution B; 1232.7 ± 31.1 ms, institution C; p = 0.002), but the mean ECV did not (26.6-27.5%, p = 0.355). After phantom-based correction, the global native T1 and ECV were 1289.7 ± 32.4 ms and 25.0 ± 2.7%, respectively, and CoV for native T1 between the three institutions decreased from 3.0 to 2.5%. The corrected native T1 value did not significantly differ between institutions (1284.5 ± 31.5 ms, institution A; 1296.5 ± 39.1 ms, institution B; 1291.3 ± 29.3 ms, institution C; p = 0.440), and neither did the ECV (24.4-25.9%, p = 0.078). CONCLUSIONS: The phantom-based correction method can provide standardized reference T1 values in healthy subjects. KEY POINTS: • After phantom-based correction, the global native T1 of 16 entire myocardial segments on 3-T cardiac MRI is 1289.4 ± 32.4 ms, and the extracellular volume fraction was 25.0 ± 2.7% for healthy subjects. • After phantom - based correction was applied, the differences in the global native T1 among institutions became insignificant, and the CoV also decreased from 3.0 to 2.5%.


Assuntos
Imageamento por Ressonância Magnética , Miocárdio , Adulto , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Voluntários Saudáveis , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Miocárdio/patologia , Imageamento por Ressonância Magnética/métodos , Padrões de Referência , Imagem Cinética por Ressonância Magnética , Meios de Contraste
15.
J Appl Microbiol ; 133(3): 2074-2082, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35737750

RESUMO

AIMS: This study aimed to investigate the molecular characterization and antimicrobial susceptibility of Corynebacterium pseudotuberculosis from skin abscesses of Korean native black goats (KNBG, Capra hircus coreanae) in South Korea. METHODS AND RESULTS: A total of 83 isolates were recovered from skin abscesses of KNBG. Of these isolates, 74 isolates were identified as C. pseudotuberculosis by phospholipase D (PLD) gene-based PCR assay. Each of the isolates possessed all 18 virulence genes (FagA, FagB, FagC, FagD, SigE, SpaC, SodC, PknG, NanH, OppA, OppB, OppC, OppD, OppF, CopC, NrdH and CpaE). The genetic diversity of C. pseudotuberculosis isolates was assessed by the phylogenetic analysis using the concatenated sequences (3073 bp) of five housekeeping genes (fusA, dnaK, infB, groeL1 and leuA) for investigating their genetic diversity. In the results, the isolates belonged to three groups: group 1 (67 isolates), group 2 (one isolate) and group 3 (six isolates) within biovar ovis. However, the groups exhibited low genetic diversity (0.20%-0.41%). In the antimicrobial susceptibility test, most isolates were susceptible to tetracycline, vancomycin, chloramphenicol, ciprofloxacin, erythromycin, enrofloxacin, cefoxitin, ampicillin, gentamycin, cephalothin and doxycycline, whereas they were not susceptible to cefotaxime, trimethoprim and streptomycin. CONCLUSION: This results suggest the involvement of relatively few clones of C. pseudotuberculosis in Korea. Further, present isolates can threaten public health due to potentially virulent strains with all 18 virulence genes and non-susceptible strains to clinically important antibiotics (CIA) and highly important antibiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first to investigate the genetic diversity and potential pathogenicity of C. pseudotuberculosis biovar ovis isolates from skin abscesses of KBNG in South Korea, and could provide useful information in controlling its infections.


Assuntos
Corynebacterium pseudotuberculosis , Abscesso/veterinária , Animais , Antibacterianos/farmacologia , Corynebacterium pseudotuberculosis/genética , Cabras/microbiologia , Filogenia , Ovinos
16.
BMC Vet Res ; 18(1): 237, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35733159

RESUMO

BACKGROUND: The aim of this study was to investigate the anti-obesity effects of DWP16001, a sodium-glucose cotransporter-2 (SGLT2 inhibitor), in naturally obese dogs. A total of 20 dogs were divided into four equal groups: one obese control (OC group), and three treated groups; DWP0.2 group, DWP0.5 group, and DWP1 group. OC group fed with food for maintenance and treated groups were fed with food for maintenance with 0.2 mg/kg DWP16001, 0.5 mg/kg DWP16001 and 1 mg/kg DWP16001, respectively. The food for maintenance was provided to dogs as 2 RER (Resting energy requirement) in kcal and DWP16001-supplemented food was administered once a day for 8 weeks. RESULTS: Body condition score, body weight, and fat thickness were significantly reduced (P < 0.05) in the DWP0.2 group compared with the OC group, respectively without affecting the food consumption. At the 10th week the food consumption rate was 101.35 ± 2.56, 166.59 ± 4.72, 98.47 ± 1.44 and 123.15 ± 2.45% compared with initial food consumption rate. Body fat percentage, chest and waist circumference, blood glucose, and insulin were reduced compared to OC group but not significantly different from those of the OC group during experimental period. Serum alanine aminotransferase, alkaline phosphatase, creatine phosphokinase, and creatinine were significantly reduced in DWP0.2 group on 8 weeks. Serum cholesterol and triglycerides were reduced but not significantly. No specific adverse effects were observed throughout the experiment, and hematological parameters were unchanged. The results indicate that DWP16001 was not harmful to the dogs in our study and might have anti-obesity effects in naturally obese dogs. CONCLUSIONS: The above results and discussion suggest that DWP16001 is safe and might have anti-obesity effects in naturally obese dogs.


Assuntos
Doenças do Cão , Obesidade , Animais , Glicemia , Peso Corporal , Doenças do Cão/tratamento farmacológico , Cães , Insulina , Obesidade/tratamento farmacológico , Obesidade/veterinária , Triglicerídeos
17.
Nano Lett ; 21(24): 10469-10477, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34881903

RESUMO

Stacking two-dimensional van der Waals (vdW) materials rotated with respect to each other show versatility for studying exotic quantum phenomena. In particular, anisotropic layered materials have great potential for such twistronics applications, providing high tunability. Here, we report anisotropic superconducting order parameters in twisted Bi2Sr2CaCu2O8+x (Bi-2212) vdW junctions with an atomically clean vdW interface, achieved using the microcleave-and-stack technique. The vdW junctions with twist angles of 0° and 90° showed the maximum Josephson coupling, comparable to that of intrinsic Josephson junctions. As the twist angle approaches 45°, Josephson coupling is suppressed, and eventually disappears at 45°. The observed twist angle dependence of the Josephson coupling can be explained quantitatively by theoretical calculation with the d-wave superconducting order parameter of Bi-2212 and finite tunneling incoherence of the junction. Our results revealed the anisotropic nature of Bi-2212 and provided a novel fabrication technique for vdW-based twistronics platforms compatible with air-sensitive vdW materials.

18.
Int J Mol Sci ; 23(1)2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-35008935

RESUMO

Actin plays critical roles in various cellular functions, including cell morphogenesis, differentiation, and movement. The assembly of actin monomers into double-helical filaments is regulated in surrounding microenvironments. Graphene is an attractive nanomaterial that has been used in various biomaterial applications, such as drug delivery cargo and scaffold for cells, due to its unique physical and chemical properties. Although several studies have shown the potential effects of graphene on actin at the cellular level, the direct influence of graphene on actin filament dynamics has not been studied. Here, we investigate the effects of graphene on actin assembly kinetics using spectroscopy and total internal reflection fluorescence microscopy. We demonstrate that graphene enhances the rates of actin filament growth in a concentration-dependent manner. Furthermore, cell morphology and spreading are modulated in mouse embryo fibroblast NIH-3T3 cultured on a graphene surface without significantly affecting cell viability. Taken together, these results suggest that graphene may have a direct impact on actin cytoskeleton remodeling.


Assuntos
Citoesqueleto de Actina/metabolismo , Fibroblastos/efeitos dos fármacos , Grafite/farmacologia , Animais , Fibroblastos/metabolismo , Cinética , Camundongos , Células NIH 3T3
19.
Int J Mol Sci ; 23(22)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36430519

RESUMO

Tiron is a potent antioxidant that counters the pathological effects of reactive oxygen species (ROS) production due to oxidative stress in various cell types. We examined the effects of tiron on mitochondrial function and osteoblastic differentiation in human periosteum-derived cells (hPDCs). Tiron increased mitochondrial activity and decreased senescence-associated ß-galactosidase activity in hPDCs; however, it had a detrimental effect on osteoblastic differentiation by reducing alkaline phosphatase (ALP) activity and alizarin red-positive mineralization, regardless of H2O2 treatment. Osteoblast-differentiating hPDCs displayed increased ROS production compared with non-differentiating hPDCs, and treatment with tiron reduced ROS production in the differentiating cells. Antioxidants decreased the rates of oxygen consumption and ATP production, which are increased in hPDCs during osteoblastic differentiation. In addition, treatment with tiron reduced the levels of most mitochondrial proteins, which are increased in hPDCs during culture in osteogenic induction medium. These results suggest that tiron exerts negative effects on the osteoblastic differentiation of hPDCs by causing mitochondrial dysfunction.


Assuntos
Osteogênese , Periósteo , Humanos , Sal Dissódico do Ácido 1,2-Di-Hidroxibenzeno-3,5 Dissulfônico , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio/farmacologia , Mitocôndrias , Antioxidantes
20.
Int J Obes (Lond) ; 45(3): 547-554, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33203924

RESUMO

BACKGROUND: Although previous reports have found that obesity intensifies the negative impact of long-term air pollution exposure on the low-density lipoprotein-cholesterol (LDL-C) level, few studies have examined whether the type of abdominal adiposity, such as visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT), and the visceral-to-subcutaneous fat ratio (VSR) affects this relationship. We investigated the association between ambient air pollution and LDL-C in Korean adults and identified whether this association is different by the type of abdominal adiposity. METHODS: A total of 2737 adults were included. Abdominal fat areas were quantified by computed tomography, and the annual average concentration of air pollutants was included in this analysis. RESULTS: In the total sample, none of the air pollutants was associated with LDL-C level in either the crude or adjusted model (all p > 0.05). The association was not significant even in subgroups stratified according to the obesity status defined by body mass index, and no interaction on the LDL-C level was also found (all pint > 0.05). In the subgroup analysis stratified according to adiposity level, particulate matter with an aerodynamic diameter of ≤10 µm (PM10) [ß (SE) = 3.58 (1.59); p = 0.0245] and sulfur dioxide (SO2) exposures [ß (SE) = 2.71 (1.27); p = 0.0330] in the high-VAT group were associated with the increased LDL-C level. Interactions on LDL-C level were also found between VAT level and ambient air pollutants such as PM10 and SO2 (both pint < 0.05). In the analysis of the VSR, PM10 exposure showed a significant interaction on LDL level (pint = 0.0032). However, the strength of these associations was not significant across all SAT subgroup (all pint > 0.05). CONCLUSIONS: In conclusion, we found that association between air pollution exposure and LDL-C level is different by abdominal fat distribution.


Assuntos
Poluição do Ar/análise , LDL-Colesterol/sangue , Exposição Ambiental/estatística & dados numéricos , Obesidade Abdominal/epidemiologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia
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