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1.
Proc Natl Acad Sci U S A ; 121(17): e2321303121, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38640342

RESUMEN

Understanding the transient dynamics of interlinked social-ecological systems (SES) is imperative for assessing sustainability in the Anthropocene. However, how to identify critical transitions in real-world SES remains a formidable challenge. In this study, we present an evolutionary framework to characterize these dynamics over an extended historical timeline. Our approach leverages multidecadal rates of change in socioeconomic data, paleoenvironmental, and cutting-edge sedimentary ancient DNA records from China's Yangtze River Delta, one of the most densely populated and intensively modified landscapes on Earth. Our analysis reveals two significant social-ecological transitions characterized by contrasting interactions and feedback spanning several centuries. Initially, the regional SES exhibited a loosely connected and ecologically sustainable regime. Nevertheless, starting in the 1950s, an increasingly interconnected regime emerged, ultimately resulting in the crossing of tipping points and an unprecedented acceleration in soil erosion, water eutrophication, and ecosystem degradation. Remarkably, the second transition occurring around the 2000s, featured a notable decoupling of socioeconomic development from ecoenvironmental degradation. This decoupling phenomenon signifies a more desirable reconfiguration of the regional SES, furnishing essential insights not only for the Yangtze River Basin but also for regions worldwide grappling with similar sustainability challenges. Our extensive multidecadal empirical investigation underscores the value of coevolutionary approaches in understanding and addressing social-ecological system dynamics.


Asunto(s)
Ecosistema , Ríos , Eutrofización , Conservación de los Recursos Naturales/métodos
2.
Arch Microbiol ; 206(4): 163, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38483624

RESUMEN

To enhance the quality of tobacco leaves and optimize the smoking experience, diverse strains of functional bacteria and their associated metabolites have been used in tobacco aging. Exogenous cellulase additives are frequently employed to facilitate the degradation of cellulose and other macromolecular matrices and enhance the quality of the tobacco product. However, little is known about how microbial metabolites present in exogenous enzyme additives affect tobacco quality. In this study, crude cellulase solutions, produced by a tobacco-originating bacterium Bacillus subtilis FX-1 were employed on flue-cured tobacco. The incorporation of cellulase solutions resulted in the reduction of cellulose crystallinity in tobacco and the enhancement of the overall sensory quality of tobacco. Notably, tobacco treated with cellulase obtained from laboratory flask fermentation demonstrated superior scent and flavor attributes in comparison to tobacco treated with enzymes derived from industrial bioreactor fermentation. The targeted and untargeted metabolomic analysis revealed the presence of diverse flavor-related precursors and components in the cellulase additives, encompassing sugars, alcohols, amino acids, organic acids, and others. The majority of these metabolites exhibited significantly higher levels in the flask group compared to the bioreactor group, probably contributing to a pronounced enhancement in the sensory quality of tobacco. Our findings suggest that the utilization of metabolic products derived from B. subtilis FX-1 as additives in flue-cured tobacco holds promise as a viable approach for enhancing sensory attributes, establishing a solid theoretical foundation for the potential development of innovative tobacco aging additives.


Asunto(s)
Bacillus subtilis , Celulasa , Bacillus subtilis/metabolismo , Celulasa/metabolismo , Celulosa/metabolismo
3.
BMC Health Serv Res ; 24(1): 766, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38918753

RESUMEN

BACKGROUND: Attracting and supporting a sustainable long-term care (LTC) workforce has been a persistent social policy challenge across the globe. To better attract and retain a sustainable LTC workforce, it is necessary to adopt a unified concept of worker well-being. Meaning of work is an important psychological resource that buffers the negative impacts of adverse working conditions on workers' motivation, satisfaction, and turnover intention. The aim of this study was to explore the positive meaning of care work with older people and its implications for health care workers' job satisfaction and motivation to work in the LTC sector. METHODS: This study adopted a qualitative descriptive design that pays particular attention to health care workers; such as nurses, personal care workers; as active agents of the meaning making and reframing of care work in LTC communities in a East Asia city. In-depth semi-structured interviews were conducted with thirty health care workers in LTC communities in Hong Kong. Thematic analysis was employed for data analysis. RESULTS: The research findings indicate that while health care workers perform demanding care work and experience external constraints, they actively construct positive meanings of care work with older people as a helping career that enables them to facilitate the comfortable aging of older people, build affectional relationships, achieve professional identity, and gain job security. CONCLUSIONS: This qualitative study explores how health care workers negotiate the positive meaning of older people care work and the implications of meaningful work for workers' job satisfaction and motivation to work in the LTC sector. The importance of a culturally sensitive perspective in researching and developing social policy intervention are suggested.


Asunto(s)
Entrevistas como Asunto , Satisfacción en el Trabajo , Investigación Cualitativa , Humanos , Masculino , Femenino , Hong Kong , Adulto , Persona de Mediana Edad , Personal de Salud/psicología , Cuidados a Largo Plazo/psicología , Motivación , Actitud del Personal de Salud , Autoimagen , Anciano , Instituciones Residenciales
4.
Plant Cell ; 32(11): 3576-3597, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32883711

RESUMEN

Pectins are abundant in the cell walls of dicotyledonous plants, but how they interact with other wall polymers and influence wall integrity and cell growth has remained mysterious. Here, we verified that QUASIMODO2 (QUA2) is a pectin methyltransferase and determined that QUA2 is required for normal pectin biosynthesis. To gain further insight into how pectin affects wall assembly and integrity maintenance, we investigated cellulose biosynthesis, cellulose organization, cortical microtubules, and wall integrity signaling in two mutant alleles of Arabidopsis (Arabidopsis thaliana) QUA2, qua2 and tsd2 In both mutants, crystalline cellulose content is reduced, cellulose synthase particles move more slowly, and cellulose organization is aberrant. NMR analysis shows higher mobility of cellulose and matrix polysaccharides in the mutants. Microtubules in mutant hypocotyls have aberrant organization and depolymerize more readily upon treatment with oryzalin or external force. The expression of genes related to wall integrity, wall biosynthesis, and microtubule stability is dysregulated in both mutants. These data provide insights into how homogalacturonan is methylesterified upon its synthesis, the mechanisms by which pectin functionally interacts with cellulose, and how these interactions are translated into intracellular regulation to maintain the structural integrity of the cell wall during plant growth and development.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/citología , Celulosa/biosíntesis , Metiltransferasas/metabolismo , Mutación , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Adhesión Celular/genética , Pared Celular/genética , Celulosa/genética , Dinitrobencenos/farmacología , Regulación de la Expresión Génica de las Plantas , Hipocótilo/citología , Hipocótilo/genética , Hipocótilo/crecimiento & desarrollo , Metiltransferasas/genética , Microtúbulos/metabolismo , Pectinas/biosíntesis , Pectinas/genética , Pectinas/metabolismo , Células Vegetales/efectos de los fármacos , Células Vegetales/metabolismo , Plantas Modificadas Genéticamente , Sulfanilamidas/farmacología , Ácidos Urónicos/metabolismo
5.
J Biomed Inform ; 139: 104310, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36773821

RESUMEN

It is extremely important to identify patients with acute pancreatitis who are at high risk for developing persistent organ failures early in the course of the disease. Due to the irregularity of longitudinal data and the poor interpretability of complex models, many models used to identify acute pancreatitis patients with a high risk of organ failure tended to rely on simple statistical models and limited their application to the early stages of patient admission. With the success of recurrent neural networks in modeling longitudinal medical data and the development of interpretable algorithms, these problems can be well addressed. In this study, we developed a novel model named Multi-task and Time-aware Gated Recurrent Unit RNN (MT-GRU) to directly predict organ failure in patients with acute pancreatitis based on irregular medical EMR data. Our proposed end-to-end multi-task model achieved significantly better performance compared to two-stage models. In addition, our model not only provided an accurate early warning of organ failure for patients throughout their hospital stay, but also demonstrated individual and population-level important variables, allowing physicians to understand the scientific basis of the model for decision-making. By providing early warning of the risk of organ failure, our proposed model is expected to assist physicians in improving outcomes for patients with acute pancreatitis.


Asunto(s)
Pancreatitis , Humanos , Enfermedad Aguda , Tiempo de Internación , Redes Neurales de la Computación , Algoritmos
6.
World J Microbiol Biotechnol ; 39(8): 199, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37193825

RESUMEN

In this study, ten strains of lactic acid bacteria were isolated from the intestine of Blainville's beaked whale (Mesoplodon densirostris),and their cholesterol-lowering activities in vitro and in vivo were investigated. The among these strains, HJ-S2 strain, which identified as Lactiplantibacillus plantarum, showed a high in vitro cholesterol-lowering rate (48.82%). Strain HJ-S2 was resistant to acid and bile salts, with a gastrointestinal survival rate of more than 80%, but was sensitive to antibiotics. Strain HJ-S2 was found to be able to adhere to HT-29 cells in an adhesion test. The number of cell adhesion was 132.52. In addition, we also performed the cholesterol-lowering activities in vivo using high-fat diet feed mouse models. Our results indicated that HJ-S2 reduced total cholesterol (TC), total glycerol (TG), and low-density lipoprotein cholesterol (LDLC) levels while increasing the high-density lipoprotein cholesterol (HDLC) level. It also alleviated the lipid accumulation in high-fat diet feed mouse liver and pancreas. Hence, HJ-S2 demonstrated appropriate cholesterol-lowering ability and has the potential to be used as a probiotic in functional foods.


Asunto(s)
Lactobacillus plantarum , Probióticos , Ratones , Animales , Colesterol/metabolismo , Ácidos y Sales Biliares/farmacología , Intestinos , Tracto Gastrointestinal , Ballenas/metabolismo , Probióticos/metabolismo , Lactobacillus plantarum/metabolismo
7.
Arch Gynecol Obstet ; 302(3): 685-692, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32602000

RESUMEN

BACKGROUND: Recent studies show that contrast-enhanced ultrasonography (CEUS) using SonoVue has the potential to improve the performance of sentinel lymph node biopsy (SLNB) in patients with early breast cancer. However, the evidence of SLNB using CEUS in patients converting from cN1 to cN0 after neoadjuvant chemotherapy (NAC) is lacking. The aim of this prospective study is to evaluate the feasibility of CEUS using SonoVue for the identification of sentinel lymph node (SLN) and the value of the combination of CEUS and blue dye (BD) for SLNB in patients converting from cN1 to cN0 following NAC. METHODS: Patients with cytology-proven node positive breast cancer at the initial diagnosis (stage T1-T3N1M0) from January 2018 to January 2019, underwent NAC. Patients converting from cN1 to cN0 following NAC were enrolled and randomized into two groups for SLNB: the combination method group using CEUS and BD together, and the single BD method group. Then all patients underwent complete axillary lymph node dissection (ALND) and primary breast surgery. Compared with the final pathological results, the identification rate, sensitivity, specificity, accuracy, false negative rate, negative predictive value, positive predictive value were recorded and compared between two methods. RESULTS: A total of 400 patients with stage T1-T3N1M0 disease underwent NAC between January 2018 to January 2019, among which 134 (33.5%) patients had clinically negative node confirmed by imaging after NAC and randomized into two groups. Each group included 67 cases. In the combination method group, contrast-enhanced lymphatic vessels in 66 cases of 67 were clearly visualized by US soon after the periareolar injection of SonoVue and the SLNs were accurately localized. The identification rate of the combination method was 98.5%%, which was significantly higher than 83.6% (56/67) using the single BD method. The mean numbers of SLNs identified by the combination method was higher than that by the single BD method. Compared with pathological diagnosis, sensitivity, specificity, accuracy, the positive predictive value, the negative predictive value, and the FNR of the combingation method were 84.4%, 100%, 89.4%, 100%, 75%, and 15.6%, respectively. In contrast, sensitivity, specificity, accuracy, the positive predictive value, the negative predictive value, and the FNR using single blue dye were 73.9%, 100%, 89.3%, 100%, 84.6%, and 26.1%, respectively. The FNR using the combination method was significantly lower than that using single BD. CONCLUSION: Identification of SLNs in patients converting from cN1 to cN0 following NAC by CEUS is a technically feasible. The combination of CEUS and BD is more effective than BD alone for SLNB in patients converting from cN1 to cN0 following NAC.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Medios de Contraste/uso terapéutico , Terapia Neoadyuvante/métodos , Ganglio Linfático Centinela/diagnóstico por imagen , Ultrasonografía/métodos , Adulto , Anciano , Neoplasias de la Mama/patología , Medios de Contraste/farmacología , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos
8.
Biomacromolecules ; 20(2): 893-903, 2019 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-30554514

RESUMEN

Model hemicellulose-cellulose composites that mimic plant cell wall polymer interactions were prepared by synthesizing deuterated bacterial cellulose in the presence of glucomannan or xyloglucan. Dilute acid pretreatment (DAP) of these materials was studied using small-angle neutron scattering, X-ray diffraction, and sum frequency generation spectroscopy. The macrofibril dimensions of the pretreated cellulose alone were smaller but with similar entanglement of macrofibrillar network as native cellulose. In addition, the crystallite size dimension along the (010) plane increased. Glucomannan-cellulose underwent similar changes to cellulose, except that the macrofibrillar network was more entangled after DAP. Conversely, in xyloglucan-cellulose the macrofibril dimensions and macrofibrillar network were relatively unchanged after pretreatment, but the cellulose Iß content was increased. Our results point to a tight interaction of xyloglucan with microfibrils while glucomannan only interacts with macrofibril surfaces. This study provides insight into roles of different hemicellulose-cellulose interactions and may help in improving pretreatment processes or engineering plants with decreased recalcitrance.


Asunto(s)
Celulosa/química , Polisacáridos/química , Pared Celular/química , Glucanos/química , Mananos/química , Plantas/química , Dispersión del Ángulo Pequeño , Difracción de Rayos X/métodos , Xilanos/química
9.
Proc Natl Acad Sci U S A ; 113(40): 11348-11353, 2016 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-27647923

RESUMEN

Cellulose, often touted as the most abundant biopolymer on Earth, is a critical component of the plant cell wall and is synthesized by plasma membrane-spanning cellulose synthase (CESA) enzymes, which in plants are organized into rosette-like CESA complexes (CSCs). Plants construct two types of cell walls, primary cell walls (PCWs) and secondary cell walls (SCWs), which differ in composition, structure, and purpose. Cellulose in PCWs and SCWs is chemically identical but has different physical characteristics. During PCW synthesis, multiple dispersed CSCs move along a shared linear track in opposing directions while synthesizing cellulose microfibrils with low aggregation. In contrast, during SCW synthesis, we observed swaths of densely arranged CSCs that moved in the same direction along tracks while synthesizing cellulose microfibrils that became highly aggregated. Our data support a model in which distinct spatiotemporal features of active CSCs during PCW and SCW synthesis contribute to the formation of cellulose with distinct structure and organization in PCWs and SCWs of Arabidopsis thaliana This study provides a foundation for understanding differences in the formation, structure, and organization of cellulose in PCWs and SCWs.


Asunto(s)
Pared Celular/enzimología , Celulosa/biosíntesis , Glucosiltransferasas/genética , Complejos Multiproteicos/química , Arabidopsis/enzimología , Arabidopsis/genética , Membrana Celular/química , Membrana Celular/enzimología , Pared Celular/genética , Celulosa/química , Regulación de la Expresión Génica de las Plantas , Glucosiltransferasas/química , Microfibrillas/química , Microfibrillas/genética , Complejos Multiproteicos/genética
10.
Plant Physiol ; 175(1): 210-222, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28768816

RESUMEN

The secondary cell walls of tracheary elements and fibers are rich in cellulose microfibrils that are helically oriented and laterally aggregated. Support cells within the leaf midribs of mosses deposit cellulose-rich secondary cell walls, but their biosynthesis and microfibril organization have not been examined. Although the Cellulose Synthase (CESA) gene families of mosses and seed plants diversified independently, CESA knockout analysis in the moss Physcomitrella patens revealed parallels with Arabidopsis (Arabidopsis thaliana) in CESA functional specialization, with roles for both subfunctionalization and neofunctionalization. The similarities include regulatory uncoupling of the CESAs that synthesize primary and secondary cell walls, a requirement for two or more functionally distinct CESA isoforms for secondary cell wall synthesis, interchangeability of some primary and secondary CESAs, and some CESA redundancy. The cellulose-deficient midribs of ppcesa3/8 knockouts provided negative controls for the structural characterization of stereid secondary cell walls in wild type P. patens Sum frequency generation spectra collected from midribs were consistent with cellulose microfibril aggregation, and polarization microscopy revealed helical microfibril orientation only in wild type leaves. Thus, stereid secondary walls are structurally distinct from primary cell walls, and they share structural characteristics with the secondary walls of tracheary elements and fibers. We propose a mechanism for the convergent evolution of secondary walls in which the deposition of aggregated and helically oriented microfibrils is coupled to rapid and highly localized cellulose synthesis enabled by regulatory uncoupling from primary wall synthesis.


Asunto(s)
Bryopsida/enzimología , Pared Celular/metabolismo , Glucosiltransferasas/metabolismo , Familia de Multigenes , Células Vegetales/metabolismo , Bryopsida/genética , Glucosiltransferasas/genética , Isoenzimas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
11.
Soc Sci Med ; 351: 116991, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38833767

RESUMEN

PURPOSE: Although discrimination has gained increasing attention in research and practice intervention for family caregivers of children with disabilities, little is known about the social determinants that associate with the perceived discrimination among caregivers, especially in non-Western contexts. This study aims to examine the socio-familial and child-level determinants of perceived discrimination among family caregivers of children with disabilities in China. METHOD: This study drew from a population-based cross-sectional survey in Shenzhen, China. Proportional quota sampling was conducted to get data from 2500 family caregivers of children with disabilities in rehabilitation service centers (response rate = 94.9%, n = 2373), accounting for 25% of the total population of children with disabilities receiving service in Shenzhen. Latent profile analysis was conducted to categorize three perceived discrimination groups among caregivers (i.e., severe perceived discrimination group, moderate perceived discrimination group, and low perceived discrimination group). The multinomial logistic regression models were conducted to test the association between these social determinants and perceived discrimination. RESULTS: Most caregivers (82.9%) reported moderate or severe levels of perceived discrimination. Caregivers of children with moderate and severe impairments and children with mental and multiple disabilities were more vulnerable to perceiving severe social discrimination. Socio-familial characteristics, particularly the intersectionality between gender and employment, influence caregivers' perceived discrimination. CONCLUSION: Caregivers of children with disabilities experience pervasive social discrimination in contemporary urban China. Our study demonstrates that the social construction of disablism and the affiliate discrimination against family caregivers of children with disabilities is complex and multidimensional and depends upon the children's disability and the caregivers' socio-demographic characteristics.


Asunto(s)
Cuidadores , Niños con Discapacidad , Discriminación Social , Humanos , China , Masculino , Femenino , Estudios Transversales , Niños con Discapacidad/psicología , Cuidadores/psicología , Cuidadores/estadística & datos numéricos , Niño , Adulto , Discriminación Social/psicología , Persona de Mediana Edad , Adolescente , Determinantes Sociales de la Salud , Preescolar , Factores Socioeconómicos , Percepción , Encuestas y Cuestionarios
12.
Res Sq ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38946976

RESUMEN

Objective The aim of this study was to develop a predictive model for uncorrected/actual fluid intelligence scores in 9-10 year old children using magnetic resonance T1-weighted imaging. Explore the predictive performance of an autoencoder model based on reconstruction regularization for fluid intelligence in adolescents. Methods We collected actual fluid intelligence scores and T1-weighted MRIs of 11,534 adolescents who completed baseline tasks from ABCD Data Release 3.0. A total of 148 ROIs were selected and 604 features were proposed by FreeSurfer segmentation. The training and testing sets were divided in a ratio of 7:3. To predict fluid intelligence scores, we used AE, MLP and classic machine learning models, and compared their performance on the test set. In addition, we explored their performance across gender subpopulations. Moreover, we evaluated the importance of features using the SHapley Additive Explain method. Results: The proposed model achieves optimal performance on the test set for predicting actual fluid intelligence scores (PCC = 0.209 ± 0.02, MSE = 105.212 ± 2.53). Results show that autoencoders with refactoring regularization are significantly more effective than MLPs and classical machine learning models. In addition, all models performed better on female adolescents than on male adolescents. Further analysis of relevant characteristics in different populations revealed that this may be related to gender differences in underlying fluid intelligence mechanisms. Conclusions We construct a weak but stable correlation between brain structural features and raw fluid intelligence using autoencoders. Future research may need to explore ensemble regression strategies utilizing multiple machine learning algorithms on multimodal data in order to improve the predictive performance of fluid intelligence based on neuroimaging features.

13.
J Cancer Res Clin Oncol ; 150(2): 79, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38316678

RESUMEN

INTRODUCTION: The automatic segmentation of the liver is a crucial step in obtaining quantitative biomarkers for accurate clinical diagnosis and computer-aided decision support systems. This task is challenging due to the frequent presence of noise and sampling artifacts in computerized tomography (CT) images, as well as the complex background, variable shapes, and blurry boundaries of the liver. Standard segmentation of medical images based on full-supervised convolutional networks demands accurate dense annotations. Such a learning framework is built on laborious manual annotation with strict requirements for expertise, leading to insufficient high-quality labels. METHODS: To overcome such limitation and exploit massive weakly labeled data, we relaxed the rigid labeling requirement and developed a semi-supervised double-cooperative network (SD- Net). SD-Net is trained to segment the complete liver volume from preoperative abdominal CT images by using limited labeled datasets and large-scale unlabeled datasets. Specifically, to enrich the diversity of unsupervised information, we construct SD-Net consisting of two collaborative network models. Within the supervised training module, we introduce an adaptive mask refinement approach. First, each of the two network models predicts the labeled dataset, after which adaptive mask refinement of the difference predictions is implemented to obtain more accurate liver segmentation results. In the unsupervised training module, a dynamic pseudo-label generation strategy is proposed. First each of the two models predicts unlabeled data and the better prediction is considered as pseudo-labeling before training. RESULTS AND DISCUSSION: Based on the experimental findings, the proposed method achieves a dice score exceeding 94%, indicating its high level of accuracy and its suitability for everyday clinical use.


Asunto(s)
Hígado , Tomografía Computarizada por Rayos X , Humanos , Hígado/diagnóstico por imagen
14.
Microbiol Spectr ; : e0044524, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38874403

RESUMEN

In 2016, a distinct branch of H3N2 canine influenza virus (CIV) emerged, which has mutations related to mammalian adaptation and has replaced previously prevalent strains. This branch poses a risk of zoonotic infection. To prevent and control H3N2 CIV, an H3N2 virus-like particle (VLP) vaccine based on the insect cell baculovirus expression system has been developed in the study. The H3N2 VLP vaccine induced high titers of hemagglutination inhibition (HI) antibodies in nasal and muscular immunized beagle dogs. Meanwhile, the VLP vaccine provided effective protection against homologous virus challenge comparable to inactivated H3N2 canine influenza virus. In addition, the intranasal H3N2 VLP vaccine induced significantly higher Th1, Th2, and Th17 immune responses, respectively (p,0.05). Importantly, intramuscular injection of VLP and inactivated H3N2 virus has complete protective effects against homologous H3N2 virus attacks. Nasal immunization with H3N2 VLP can partially protect beagles from H3N2 influenza. IMPORTANCE: A new antigenically and genetically distinct canine influenza virus (CIV) H3N2 clade possessing mutations associated with mammalian adaptation emerged in 2016 and substituted previously circulating strains. This clade poses a risk for zoonotic infection. In our study, intramuscular injection of the H3N2 virus-like particle (VLP) vaccine and inactivated H3N2 CIV confer completely sterilizing protection against homologous H3N2 canine influenza virus challenge. Our results provide further support for the possibility of developing VLP vaccines that can reliably induce immunity in animal species.

15.
Animals (Basel) ; 14(11)2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38891609

RESUMEN

Urban stray cats are cats without owners that survive in the wild for extended periods of time. They are one of the most common stray animals in cities, and as such, monitoring the pathogens carried by urban stray cats is an important component of urban epidemiological surveillance. In order to understand the prevalence of respiratory diseases in urban stray cats in Shanghai and provide scientific evidence for the development of targeted prevention and control strategies for respiratory diseases in stray cats, we collected 374 ocular, nasal, and oropharyngeal swabs from urban stray cats in Shanghai from January 2022 to December 2022. After RNA extraction, we used real-time PCR to detect six respiratory pathogens, including influenza A virus, feline calicivirus, feline herpesvirus type 1, Mycoplasma, Chlamydia, and Bordetella bronchiseptica. The results showed that among the 374 samples, 146 tested positive, with a positivity rate of 39.04%. The highest positivity rate was observed for Mycoplasma felis at 18.72% (70/374), followed by Chlamydia felis at 11.76% (44/374), feline calicivirus at 3.74% (14/374), feline herpesvirus 1 at 3.48% (13/374), Bordetella bronchiseptica at 1.34% (5/374), and influenza A virus was not detected. The highest positivity rate for Mycoplasma felis was in Minhang District at 31.94% (23/72), while Chlamydia felis and Bordetella bronchiseptica had the highest positivity rates in Jiading District at 23.53% (8/34) and 5.88% (2/34), respectively. The highest positivity rates for feline calicivirus and feline herpesvirus 1 were both observed in Qingpu District, at 14.46% (12/83) and 9.64% (8/83), respectively. A total of 36 samples showed mixed infections with two or more pathogens, with Mycoplasma felis being involved in 32 of these mixed infections, with the highest number of mixed infections being with Chlamydia felis at 25 samples. Respiratory pathogen positivity was detected throughout the year, with peak detection rates in summer and winter. The positivity rates of cat respiratory pathogens in different seasons showed statistical differences (χ2 = 27.73, p < 0.01). There was no statistical difference in the positivity rates of respiratory pathogens between cats of different genders (χ2 = 0.92, p > 0.05). The positivity rates of respiratory pathogens in cats of different age groups showed statistical differences (χ2 = 44.41, p < 0.01). Mycoplasma felis and Chlamydia felis were the main pathogens causing respiratory infections in stray cats, with Mycoplasma felis showing a much higher positivity rate than other respiratory pathogens and often co-infecting with Chlamydia felis and feline calicivirus. The positivity rate of Mycoplasma felis was high in summer, autumn, and winter, with no statistical difference between seasons. These results indicate a serious overall prevalence of respiratory pathogens in urban stray cats in the Shanghai area, showing seasonal trends and mixed infections with other pathogens. These findings suggest the need for comprehensive prevention and control measures to address respiratory pathogen infections in urban stray cats in the Shanghai area.

16.
Sci Total Environ ; 855: 158752, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36108861

RESUMEN

Highly dispersed iron nanoclusters on carbon (FeNC@C) hold great promise for wastewater purification in Fenton-like reactions. The microenvironment engineering of central Fe atom is promising to boost the activation capacity of FeNC@C, which is however remains a challenge. This study developed a self-sacrificed templating strategy to S, N-codoped carbon supported Fe nanoclusters (FeNC@SNC) activator and find the key role of sulfur heteroatoms in regulating the electron structure of Fe sites and final activation property. Investigations revealed that the FeNC@SNC composite exhibited unusual bifunctional activity in both peroxymonosulfate (PMS)- and periodate (PI)-based Fenton-like reactions. We also offered insights into the differences between the degradation of organics by the FeNC@SNC/PMS and FeNC@SNC/PI systems. Specifically, under identical conditions, the FeNC@SNC/PMS system delivered a higher oxidation capability and stronger resistance to nontarget matrix constituents, but showed more severe Fe leaching than the FeNC@SNC/PI system. Furthermore, while mediated electron-transfer process was identified as the major route for pollutant decomposition in both systems, the high-valent Fe-oxo species [Fe (IV)] was the auxiliary reactive species found only in the FeNC@SNC/PMS system. Based on these findings, our results provide profound insights into the design of active and durable Fe-based activators toward highly efficient Fenton-like reactions.


Asunto(s)
Carbono , Hierro , Hierro/química , Carbono/química , Nitrógeno , Azufre
17.
Cell Death Discov ; 9(1): 341, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37704618

RESUMEN

Hypertrophic scar (HS) is an abnormal fibrous hyperplasia of the skin caused by excessive tissue repair in response to skin burns and trauma, which restricts physical function and impairs patients' quality of life. Numerous studies have shown that pressure garment therapy (PGT) is an effective treatment for preventing hypertrophic scars. Herein, we found that mechanical stress stimulates the neuropilin 1 (NRP1) expression through screening GSE165027, GSE137210, and GSE120194 from Gene Expression Omnibus (GEO) database and bioinformatics analysis. We verified this stimulation in the human hypertrophic scar, pressure culture cell model, and rat tail-scar model. Mechanical compression increased LATS1 and pYAP enrichment, thus repressing the expression of YAP. Functionally, the knockdown of NRP1 promoted the expression of LATS1, thus decreasing the expression of YAP and inhibiting endothelial cell proliferation. Furthermore, co-immunoprecipitation analysis confirmed that NRP1 binds to YAP, and mechanical compression disrupted this binding, which resulted in the promotion of YAP relocation to nuclear. In conclusion, our results indicated that NRP1 transduces mechanical force inhibition by inhibiting YAP expression. Mechanical pressure can release YAP bound to NRP1, which explains the phenomenon that mechanical stress increases YAP in the nucleus. Strategies targeting NRP1 may promote compression therapy with optimal and comfortable pressures.

18.
Water Res ; 235: 119916, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37003114

RESUMEN

Harmful algal blooms (HABs) producing toxic metabolites are increasingly threatening environmental and human health worldwide. Unfortunately, long-term process and mechanism triggering HABs remain largely unclear due to the scarcity of temporal monitoring. Retrospective analysis of sedimentary biomarkers using up-to-date chromatography and mass spectrometry techniques provide a potential means to reconstruct the past occurrence of HABs. By combining aliphatic hydrocarbons, photosynthetic pigments, and cyanotoxins, we quantified herein century-long changes in abundance, composition, and variability of phototrophs, particularly toxigenic algal blooms, in China's third largest freshwater Lake Taihu. Our multi-proxy limnological reconstruction revealed an abrupt ecological shift in the 1980s characterized by elevated primary production, Microcystis-dominated cyanobacterial blooms, and exponential microcystin production, in response to nutrient enrichment, climate change, and trophic cascades. The empirical results from ordination analysis and generalized additive models support climate warming and eutrophication synergy through nutrient recycling and their feedback through buoyant cyanobacterial proliferation, which sustain bloom-forming potential and further promote the occurrence of increasingly-toxic cyanotoxins (e.g., microcystin-LR) in Lake Taihu. Moreover, temporal variability of the lake ecosystem quantified using variance and rate of change metrics rose continuously after state change, indicating increased ecological vulnerability and declined resilience following blooms and warming. With the persistent legacy effects of lake eutrophication, nutrient reduction efforts mitigating toxic HABs probably be overwhelmed by climate change effects, emphasizing the need for more aggressive and integrated environmental strategies.


Asunto(s)
Cianobacterias , Floraciones de Algas Nocivas , Humanos , Ecosistema , Estudios Retrospectivos , Eutrofización , Lagos/química , Biomarcadores , China
19.
Int J Food Microbiol ; 401: 110273, 2023 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37295267

RESUMEN

Staphylococcus aureus (S. aureus) is a major cause of foodborne infections and its persistence in raw milk is a multifaceted phenomenon that poses a considerable public health challenge. Our study investigated the prevalence, virulence genes, antibiotic resistance, and genetic characterization of S. aureus in raw milk in six Shanghai districts from 2013 to 2022. At 18 dairy farms, a total of 704 S. aureus strains were isolated from 1799 samples tested for drug sensitivity. The highest rates of antibiotic resistance were ampicillin (96.7 %), sulfamethoxazole (65 %), and erythromycin (21.6 %). Between 2018 and 2022, there was a significant decrease in the resistance rates of ceftiofur, ofloxacin, tilmicosin, erythromycin, clindamycin, amoxicillin-clavulanic acid, and sulfamethoxazole in comparison to the period from 2013 to 2017. There were 205 S. aureus strains chosen for whole genome sequencing (WGS), with no more than 2 strains of the same resistance phenotype from each farm per year. The prevalence of mecA-positive strains was 14.15 %, while other antibiotic resistance-associated genes were observed as follows: blaI (70.21 %), lnu(B) (5.85 %), lsa(E) (5.75 %), fexA (6.83 %), erm(C) (4.39 %), tet(L) (9.27 %), and dfrG (5.85 %). Isolates harboring the immune evasion cluster (IEC) genes (scn, chp, and sak) were predominantly categorized as sequence types (STs) 7, 188, 15, 59, and 398. The predominant cluster complexes were CC97, CC1, CC398, and CC1651. In 2017-2022, there was a transition in CC1 from the highly antibiotic-resistant ST9 strain that emerged between 2013 and 2018 to the low-resistant but highly virulent ST1 strain. Retrospective phylogenetic analysis elucidated the evolutionary history of the isolates and demonstrated that the human-animal host transition of S. aureus was linked to the genesis of MRSA CC398. The implementation of extended surveillance will aid in the development of innovative strategies to avoid the transmission of S. aureus along the dairy food chain and the occurrence of public health events.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Humanos , Staphylococcus aureus/genética , Virulencia/genética , Leche , Filogenia , Estudios Retrospectivos , China , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/veterinaria , Antibacterianos/farmacología , Eritromicina , Farmacorresistencia Microbiana , Sulfametoxazol , Variación Genética , Staphylococcus aureus Resistente a Meticilina/genética , Pruebas de Sensibilidad Microbiana
20.
Sci Total Environ ; 876: 162807, 2023 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-36921865

RESUMEN

In Shanghai, the prevalence of tet(X4) and tet(X4)-carrying plasmid from food-producing -animal Enterobacteriales has not been intensively investigated. Here, five tet(X4)-positive swine-origin E. coli strains were characterized among 652 food-producing-animal E. coli isolates in Shanghai during 2018-2021 using long-term surveillance among poultry, swine and cattle, antimicrobial susceptibility testing, and tet(X4)-specific PCR. A combination of short- and long-read sequencing technologies demonstrated that the five strains with 4 STs carried a nearly identical 193 kb tet(X4)-bearing plasmid (p193k-tetX4) belonging to the same IncFIA(HI1)/IncHI1A/IncHIB plasmid family (p193k). Surprisingly, 34 of the 151 global tet(X4)-positive plasmids was the p193k members and exclusively pandemic in China. Other p193k members harboring many critically important ARGs (mcr or blaNDM) with particular genetic environment are widespread throughout human-animal-environmental sources, with 33.77 % human origin. Significantly, phylogenetic analysis of 203 p193k-tetX4 sequences revealed that human- and animal-origin plasmids clustered within the same phylogenetic subgroups. The largest lineage (173/203) comprised 161 E. coli, 6 Klebsiella, 3 Enterobacter, 2 Citrobacter, and 1 Leclercia spp. from animals (n = 143), humans (n = 18), and the environment (n = 9). Intriguingly, the earliest 2015 E. coli strain YA_GR3 from Malaysian river water and 2016 S. enterica Chinese clinical strain GX1006 in another lineage demonstrated that p193k-tetX4 have been widely spread from S. enterica or E. coli to other Enterobacterales. Furthermore, 180 E. coli p193k-tetX4 strains were widespread cross-sectorial transmission among food animals, pets, migratory birds, human and ecosystems. Our findings proved the extensive transmission of the high-risk p193k harboring crucial ARGs across multiple interfaces and species. Therefore, one-health-based systemic surveillance of these similar high-risk plasmids across numerous sources and bacterial species is extremely essential.


Asunto(s)
Farmacorresistencia Bacteriana , Infecciones por Escherichia coli , Escherichia coli , Animales , Bovinos , Humanos , China , Ecosistema , Escherichia coli/genética , Escherichia coli/patogenicidad , Pruebas de Sensibilidad Microbiana , Filogenia , Plásmidos , Salud Pública , Porcinos , Infecciones por Escherichia coli/microbiología , Farmacorresistencia Bacteriana/genética
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