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1.
Carbohydr Polym ; 339: 122261, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38823925

ABSTRACT

Understanding the distribution and accessibility of polymers within plant cell walls is crucial for addressing biomass recalcitrance in lignocellulosic materials. In this work, Imaging Fourier Transform Infrared (FTIR) and Raman spectroscopy, coupled with targeted chemical treatments, were employed to investigate cell wall polymer distribution in two bamboo species at both tissue and cell wall levels. Tissue-level Imaging FTIR revealed significant disparities in the distribution and chemical activity of cell wall polymers between the fibrous sheath and fibrous strand. At the cell wall level, Imaging Raman spectroscopy delineated a distinct difference between the secondary wall and intercellular layer, with the latter containing higher levels of lignin, hydroxycinnamic acid (HCA), and xylan, and lower cellulose. Mild acidified sodium chlorite treatment led to partial removal of lignin, HCA, and xylan from the intercellular layer, albeit to a lesser extent than alkaline treatment, indicating susceptibility of these polymers to chemical treatment. In contrast, lignin in the secondary wall exhibited limited reactivity to acidified sodium chlorite but was slightly removed by alkaline treatment, suggesting stable chemical properties with slight alkaline intolerance. These findings provide valuable insights into the inherent design mechanism of plant cells and their efficient utilization.


Subject(s)
Cell Wall , Cellulose , Coumaric Acids , Lignin , Cell Wall/chemistry , Lignin/chemistry , Coumaric Acids/chemistry , Cellulose/chemistry , Spectroscopy, Fourier Transform Infrared/methods , Xylans/chemistry , Spectrum Analysis, Raman/methods , Sasa/chemistry , Chlorides/chemistry , Polymers/chemistry
2.
Int J Biol Macromol ; 274(Pt 1): 133341, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38908621

ABSTRACT

Biomass recalcitrance, a key challenge in biomass utilization, is closely linked to the architectural composition and cross-linkages of molecules within cell walls. With three bamboo species investigated, this study aims to elucidate the inherent molecular-scale structural differences between bamboo fibers and parenchyma cells through a systematic chemical extraction and structural characterization of isolated hemicelluloses, lignin, and lignin-carbohydrate complexes (LCC). We observed that parenchyma cells exhibit superior alkaline extractability compared to fibers. Additionally, we identified the hemicelluloses in parenchyma cells as L-arabino-4-O-methyl-D-glucurono-D-xylan, displaying a highly branched structure, while that in fibers is L-arabino-D-xylan. Furthermore, the parenchyma cell lignin exhibited a higher syringyl-to-guaiacyl (S/G) ratio and ß-O-4 linkage content compared to fibers, whereas fibers contain more carbon­carbon linkages including ß-ß, ß-5, and ß-1. This notable structural difference suggests a denser and more stable lignin in bamboo fibers. Importantly, we found that LCC in parenchyma cells predominantly comprises γ-ester linkages, which exhibit an alkaline-unstable nature. In contrast, fibers predominantly contain phenyl glycoside linkages, characterized by their alkaline-stable nature. These findings were observed for all the tested bamboo species, indicating the conclusions should be also valid for other bamboo species, suggesting the competitiveness of bamboo parenchyma cells as a valuable biofuel feedstock.

3.
iScience ; 27(3): 109204, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38420591

ABSTRACT

Pathogenic mycobacteria orchestrate the complex cell populations known as granuloma that is the hallmark of tuberculosis. Foam cells, a lipid-rich cell-type, are considered critical for granuloma formation; however, the causative factor in foam cell formation remains unclear. Atherosclerosis is a chronic inflammatory disease characterized by the abundant accumulation of lipid-laden-macrophage-derived foam cells during which cholesterol 25-hydroxylase (CH25H) is crucial in foam cell formation. Here, we show that M. marinum (Mm), a relative of M. tuberculosis, induces foam cell formation, leading to granuloma development following CH25H upregulation. Moreover, the Mm-driven increase in CH25H expression is associated with the presence of phthiocerol dimycocerosate, a determinant for Mm virulence and integrity. CH25H-null mice showed decreased foam cell formation and attenuated pathology. Atorvastatin, a recommended first-line lipid-lowering drug, promoted the elimination of M. marinum and concomitantly reduced CH25H production. These results define a previously unknown role for CH25H in controlling macrophage-derived foam cell formation and Tuberculosis pathology.

4.
Clin Kidney J ; 17(1): sfad137, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38186904

ABSTRACT

Introduction: Chronic kidney disease (CKD) is a significant public health problem, with rising incidence and prevalence worldwide, and is associated with increased morbidity and mortality. Early identification and treatment of CKD can slow its progression and prevent complications, but it is not clear whether CKD screening is cost-effective. The aim of this study is to conduct a systematic review of the cost-effectiveness of CKD screening strategies in general adult populations worldwide, and to identify factors, settings and drivers of cost-effectiveness in CKD screening. Methods: Studies examining the cost-effectiveness of CKD screening in the general adult population were identified by systematic literature search on electronic databases (MEDLINE OVID, Embase, Cochrane Library and Web of Science) for peer-reviewed publications, hand-searched reference lists and grey literature of relevant sites, focusing on the following themes: (i) CKD, (ii) screening and (iii) cost-effectiveness. Studies comprising health economic evaluations performed for CKD screening strategies, compared with no CKD screening or usual-care strategy in adult individuals, were included. Study characteristics, model assumptions and CKD screening strategies of selected studies were identified. The primary outcome of interest is the incremental cost-effectiveness ratio (ICER) of CKD screening, in cost per quality-adjusted life year (QALY) and life-year gained (LYG), expressed in 2022 US dollars equivalent. Results: Twenty-one studies were identified, examining CKD screening in general and targeted populations. The cost-effectiveness of screening for CKD was found to vary widely across different studies, with ICERs ranging from $113 to $430 595, with a median of $26 662 per QALY and from $6516 to $38 372, with a median of $29 112 per LYG. Based on the pre-defined cost-effectiveness threshold of $50 000 per QALY, the majority of the studies found CKD screening to be cost-effective. CKD screening was especially cost-effective in those with diabetes ($113 to $42 359, with a median of $27 471 per QALY) and ethnic groups identified to be higher risk of CKD development or progression ($23 902 per QALY in African American adults and $21 285 per QALY in Canadian indigenous adults), as indicated by a lower ICER. Additionally, the cost-effectiveness of CKD screening improved if it was performed in older adults, populations with higher CKD risk scores, or when setting a higher albuminuria detection threshold or increasing the interval between screening. In contrast, CKD screening was not cost-effective in populations without diabetes and hypertension (ICERs range from $117 769 to $1792 142, with a median of $202 761 per QALY). Treatment effectiveness, prevalence of CKD, cost of CKD treatment and discount rate were identified to be the most common influential drivers of the ICERs. Conclusions: Screening for CKD is especially cost-effective in patients with diabetes and high-risk ethnic groups, but not in populations without diabetes and hypertension. Increasing the age of screening, screening interval or albuminuria detection threshold, or selection of population based on CKD risk scores, may increase cost-effectiveness of CKD screening, while treatment effectiveness, prevalence of CKD, cost of CKD treatment and discount rate were influential drivers of the cost-effectiveness.

5.
Environ Sci Pollut Res Int ; 30(53): 113609-113621, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37851265

ABSTRACT

Along with the continuous improvement of industrial intelligence, robots are widely used in various aspects of production and life, playing an essential role in achieving carbon reduction targets. However, the existing research on the carbon reduction effect of robots and its mechanism is limited. Therefore, this study aims to explore the impact of robot adoption on carbon emissions and analyzes the mechanism by taking 30 provinces in China from 2006 to 2019 as research objects. It found that robot adoption can significantly reduce carbon emissions. However, the degree of marketization plays a masking effect, which limits robots' carbon reduction effect to some extent. Furthermore, the carbon reduction effect of robot adoption is stronger in provinces with lower carbon emissions. Finally, robot adoption has a significant spatial spillover effect on neighboring regions. The improvement of robot adoption will positively affect the region's and surrounding areas' carbon emission reduction. The relevant findings provide empirical support for further deepening the policy implementation of robot-assisted carbon emission reduction.


Subject(s)
Robotics , Carbon , China , Industry , Policy , Carbon Dioxide , Economic Development
6.
J Colloid Interface Sci ; 652(Pt A): 258-271, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37595443

ABSTRACT

Nowadays, electromagnetic radiation significantly impacts the normal operation of electronic devices and poses risks to human health. To effectively address this problem, the development of composites that exhibit exceptional electrochemical wave absorption through the combination of different components holds great promise. In this study, we have successfully prepared 1D Ni nanochains@Zn2+ doping polypyrrole/reduced graphene oxide (Ni NCs@Z-P/RGO, denoted as R-x) composites using a combination of hydrothermal, solvothermal, in situ polymerization, and physical blending methods. Notably, the R-2 composite demonstrates a remarkable minimum reflection loss (RLmin) of -63.58 dB at 14.3 GHz, with a thickness of 1.61 mm. Furthermore, the R-2 composite exhibits an impressive effective absorption bandwidth (EAB) of 5.08 GHz (11.92 GHz-17 GHz) at a thickness of 1.67 mm. These outstanding performances can be attributed to the synergistic effect of the different components and a well-thought-out structural design. Moreover, to showcase the practical applicability of the material, we have conducted additional investigations on the reduction of the radar cross-sectional area (RCS). The results strongly demonstrate that the prepared composite material, when used as a coating, effectively reduces the RCS value by up to 26.6 dB m2 for R-2 at θ = 0°. The experimental methods and simulations presented in this study hold significant potential for application in wave absorption research and practical implementations. Additionally, the prepared Ni NCs@Z-P/RGO composites demonstrate feasibility as wave-absorbing materials for future utilization.

7.
J Colloid Interface Sci ; 649: 943-954, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37392684

ABSTRACT

The design of heterostructures with reasonable chemical composition and spatial structure is one of the effective strategies to achieve high performances electromagnetic wave (EMW) absorption. Herein, reduced graphene oxide (rGO) nanosheets decorated with hollow core-shell Fe3O4@PPy (FP) microspheres have been prepared by the combination of hydrothermal method, in situ polymerization method, directional freeze-drying and hydrazine vapor reduction. FP acting as traps can consume EMW trapped into their interior through the magnetic and dielectric losses. RGO nanosheets forming the conductive network are served as multi-reflected layers. Moreover, the impedance matching is optimized by the synergistic effect between FP and rGO. As expected, the synthetic Fe3O4@PPy/rGO (FPG) composite shows excellent EMW absorption performances with the minimum reflect loss (RLmin) of -61.20 dB at 1.89 mm and the effective absorption bandwidth (EAB) of 5.26 GHz at 1.71 mm. The excellent performances for the heterostructure are attributed to the synergistic effect of conductive loss, dielectric loss, magnetic loss, multiple reflection loss, and optimized impedance matching. This work provides a simple and effective strategy for the fabrication of lightweight, thin and high-performances EMW absorbing materials.

8.
Viruses ; 15(4)2023 04 20.
Article in English | MEDLINE | ID: mdl-37112994

ABSTRACT

Interferon-γ (IFN-γ) is a critical component of innate immune responses in humans to combat infection by many viruses, including human cytomegalovirus (HCMV). IFN-γ exerts its biological effects by inducing hundreds of IFN-stimulated genes (ISGs). In this study, RNA-seq analyses revealed that HCMV tegument protein UL23 could regulate the expression of many ISGs under IFN-γ treatment or HCMV infection. We further confirmed that among these IFN-γ stimulated genes, individual APOL1 (Apolipoprotein-L1), CMPK2 (Cytidine/uridine monophosphate kinase 2), and LGALS9 (Galectin-9) could inhibit HCMV replication. Moreover, these three proteins exhibited a synergistic effect on HCMV replication. UL23-deficient HCMV mutants induced higher expression of APOL1, CMPK2, and LGALS9, and exhibited lower viral titers in IFN-γ treated cells compared with parental viruses expressing full functional UL23. Thus, UL23 appears to resist the antiviral effect of IFN-γ by downregulating the expression of APOL1, CMPK2, and LGALS9. This study highlights the roles of HCMV UL23 in facilitating viral immune escape from IFN-γ responses by specifically downregulating these ISGs.


Subject(s)
Cytomegalovirus , Interferon-gamma , Humans , Antiviral Agents/pharmacology , Apolipoprotein L1 , Immunity, Innate , Interferon-gamma/pharmacology , Virus Replication , Viral Proteins/genetics , Viral Proteins/metabolism
9.
J Am Heart Assoc ; 12(7): e026975, 2023 04 04.
Article in English | MEDLINE | ID: mdl-36942750

ABSTRACT

BACKGROUND Electrocardiography (ECG) may be performed as part of preparticipation sports screening. Recommendations on screening of athletes to identify individuals with previously unrecognized cardiac disease are robust; however, data guiding the preparticipation screening of unselected populations are scarce. T wave inversion (TWI) on ECG may suggest an undiagnosed cardiomyopathy. This study aims to describe the prevalence of abnormal TWI in an unselected young male cohort and the outcomes of an echocardiography-guided approach to investigating these individuals for structural heart diseases, focusing on the yield for cardiomyopathies. METHODS AND RESULTS Consecutive young male individuals undergoing a national preparticipation cardiac screening program for 39 months were studied. All underwent resting supine 12-lead ECG. Those manifesting abnormal TWI, defined as negatively deflected T waves of at least 0.1 mV amplitude in any 2 contiguous leads, underwent echocardiography. A total of 69 714 male individuals with a mean age of 17.9±1.1 years were studied. Of the individuals, 562 (0.8%) displayed abnormal TWI. This was most frequently observed in the anterior territory and least so in the lateral territory. A total of 12 individuals (2.1%) were diagnosed with a cardiomyopathy. Cardiomyopathy diagnoses were significantly associated with deeper maximum TWI depth and the presence of abnormal TWI in the lateral territory, but not with abnormal TWI in the anterior and inferior territories. No individual presenting with TWI restricted to solely leads V1 to V2, 2 inferior leads or both was diagnosed with a cardiomyopathy. CONCLUSIONS Cardiomyopathy diagnoses were more strongly associated with certain patterns of abnormal TWI. Our findings may support decisions to prioritize echocardiography in these individuals.


Subject(s)
Cardiomyopathies , Echocardiography , Heart Diseases , Adolescent , Adult , Humans , Male , Young Adult , Arrhythmias, Cardiac/diagnosis , Cardiomyopathies/diagnosis , Electrocardiography/methods , Heart
10.
BMJ Open ; 13(2): e066375, 2023 02 23.
Article in English | MEDLINE | ID: mdl-36822814

ABSTRACT

OBJECTIVE: To examine whether increases in physician volume in primary healthcare facilities are associated with reduced utilisation of hospital outpatient and inpatient services after China facilitated the establishment of the hierarchical medical system. DESIGN: We used a two-way fixed-effects regression to examine the association between the annual number of physicians in primary healthcare facilities and that of patient visits per physician, inpatient admissions and total expenses per outpatient visit in public hospitals during 2010-2014 and 2015-2019. Variables were log transformed to ensure the normal distribution of the data. SETTING: Province-level data of all 31 provinces in mainland China from 2010 to 2019 were collected from the China Health Statistics Yearbook published by the China Health Commission. PARTICIPANTS: All 31 provinces in mainland China. PRIMARY AND SECONDARY OUTCOME MEASURES: The annual number of outpatient visits per physician, hospital admission and total expenses per outpatient visit in public hospitals. RESULTS: During 2015-2019, we found that, on average, a 1% increase in the number of primary healthcare physicians was accompanied by a 0.19% (95% CI -0.33% to -0.05%) reduction in the annual number of visits per physician in public hospitals, and a 0.31% (95% CI -0.52% to -0.10%) reduction in patient visits in city-administered hospitals. No significant associations were found between 2010 and 2014. We also did not observe any significant associations between primary healthcare physician volume and hospital admissions or outpatient expenses during neither 2010-2014 and 2015-2019. CONCLUSIONS: In the context of the hierarchical medical system, enhancing physician volume in primary healthcare facilities helps reduce outpatient visits in public hospitals, especially city-administered hospitals. However, more efforts are required to be continuously made to improve primary healthcare capacity to avoid preventable hospital admissions and outpatient expenses.


Subject(s)
Hospitals, Public , Physicians , Humans , Hospitalization , China , Primary Health Care
12.
Front Microbiol ; 14: 1301141, 2023.
Article in English | MEDLINE | ID: mdl-38235425

ABSTRACT

Introduction: Granulomas, the pathological hallmark of Mycobacterium tuberculosis (Mtb) infection, are formed by different cell populations. Across various stages of tuberculosis conditions, most granulomas are classical caseous granulomas. They are composed of a necrotic center surrounded by multilayers of histocytes, with the outermost layer encircled by fibrosis. Although fibrosis characterizes the architecture of granulomas, little is known about the detailed parameters of fibrosis during this process. Methods: In this study, samples were collected from patients with tuberculosis (spanning 16 organ types), and Mtb-infected marmosets and fibrotic collagen were characterized by second harmonic generation (SHG)/two-photon excited fluorescence (TPEF) microscopy using a stain-free, fully automated analysis program. Results: Histopathological examination revealed that most granulomas share common features, including necrosis, solitary and compact structure, and especially the presence of multinuclear giant cells. Masson's trichrome staining showed that different granuloma types have varying degrees of fibrosis. SHG imaging uncovered a higher proportion (4%~13%) of aggregated collagens than of disseminated type collagens (2%~5%) in granulomas from matched tissues. Furthermore, most of the aggregated collagen presented as short and thick clusters (200~620 µm), unlike the long and thick (200~300 µm) disseminated collagens within the matched tissues. Matrix metalloproteinase-9, which is involved in fibrosis and granuloma formation, was strongly expressed in the granulomas in different tissues. Discussion: Our data illustrated that different tuberculosis granulomas have some degree of fibrosis in which collagen strings are short and thick. Moreover, this study revealed that the SHG imaging program could contribute to uncovering the fibrosis characteristics of tuberculosis granulomas.

13.
Arq. bras. cardiol ; 119(6): 940-945, dez. 2022. tab, graf
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1420136

ABSTRACT

Resumo Fundamento A síndrome de Wolff-Parkinson-White (WPW) é uma condição pró-arrítmica que pode exigir restrição de atividades extenuantes e é caracterizada por sinais de ECG, incluindo ondas delta. Observamos casos de padrões intermitentes de WPW apresentando-se como QRS alternante ('WPW alternante') em uma grande coorte de triagem de ECG pré-participação de homens jovens que se candidataram ao recrutamento militar. Objetivos Nosso objetivo foi determinar o padrão de WPW alternante, as características do caso e a prevalência de outros diagnósticos diferenciais relevantes apresentando-se como alternância de QRS em um ambiente de pré-participação. Métodos Cento e vinte e cinco mil cento e cinquenta e oito recrutas militares do sexo masculino prospectivos foram revisados de janeiro de 2016 a dezembro de 2019. Uma revisão de prontuários médicos eletrônicos identificou casos de WPW alternante e padrões ou síndrome de WPW. A revisão de prontuários médicos eletrônicos identificou casos de diagnósticos diferenciais relevantes que podem causar alternância de QRS. Resultados Quatro indivíduos (2,2%) apresentaram WPW alternante em 184 indivíduos com diagnóstico final de padrão ou síndrome de WPW. Dois desses indivíduos manifestaram sintomas ou achados eletrocardiográficos compatíveis com taquicardia supraventricular. A prevalência geral de WPW alternante foi de 0,003%, e a prevalência de WPW foi de 0,147%. As WPW alternantes representaram 8,7% dos indivíduos com QRS alternantes, e QRS alternantes tiveram prevalência de 0,037% em toda a população. Conclusões A WPW alternante é uma variante da WPW intermitente, que compreendeu 2,2% dos casos de WPW em nossa coorte de triagem pré-participação. Não indica necessariamente um baixo risco de taquicardia supraventricular. Deve ser reconhecido na triagem de ECG e distinguido de outras patologias que também apresentam QRS alternantes.


Abstract Background Wolff-Parkinson-White (WPW) syndrome is a proarrhythmic condition that may require restriction from strenuous activities and is characterized by ECG signs, including delta waves. We observed cases of intermittent WPW patterns presenting as QRS alternans ('WPW alternans') in a large pre-participation ECG screening cohort of young men reporting for military conscription. Objectives We aimed to determine the WPW alternans pattern, case characteristics, and the prevalence of other relevant differential diagnoses presenting as QRS alternans in a pre-participation setting. Methods One hundred twenty-five thousand one hundred fifty-eight prospective male military recruits were reviewed from January 2016 to December 2019. A review of electronic medical records identified cases of WPW alternans and WPW patterns or syndrome. Reviewing electronic medical records identified cases of relevant differential diagnoses that might cause QRS alternans. Results Four individuals (2.2%) had WPW alternans out of 184 individuals with a final diagnosis of WPW pattern or syndrome. Two of these individuals manifested symptoms or ECG findings consistent with supraventricular tachycardia. The overall prevalence of WPW alternans was 0.003%, and the prevalence of WPW was 0.147%. WPW alternans represented 8.7% of individuals presenting with QRS alternans, and QRS alternans had a prevalence of 0.037% in the entire population. Conclusions WPW alternans is a variant of intermittent WPW, which comprised 2.2% of WPW cases in our pre-participation screening cohort. It does not necessarily indicate a low risk for supraventricular tachycardia. It must be recognized at ECG screening and distinguished from other pathologies that also present with QRS alternans.

14.
Arq Bras Cardiol ; 119(6): 940-945, 2022 12.
Article in English, Portuguese | MEDLINE | ID: mdl-36417617

ABSTRACT

BACKGROUND: Wolff-Parkinson-White (WPW) syndrome is a proarrhythmic condition that may require restriction from strenuous activities and is characterized by ECG signs, including delta waves. We observed cases of intermittent WPW patterns presenting as QRS alternans ('WPW alternans') in a large pre-participation ECG screening cohort of young men reporting for military conscription. OBJECTIVES: We aimed to determine the WPW alternans pattern, case characteristics, and the prevalence of other relevant differential diagnoses presenting as QRS alternans in a pre-participation setting. METHODS: One hundred twenty-five thousand one hundred fifty-eight prospective male military recruits were reviewed from January 2016 to December 2019. A review of electronic medical records identified cases of WPW alternans and WPW patterns or syndrome. Reviewing electronic medical records identified cases of relevant differential diagnoses that might cause QRS alternans. RESULTS: Four individuals (2.2%) had WPW alternans out of 184 individuals with a final diagnosis of WPW pattern or syndrome. Two of these individuals manifested symptoms or ECG findings consistent with supraventricular tachycardia. The overall prevalence of WPW alternans was 0.003%, and the prevalence of WPW was 0.147%. WPW alternans represented 8.7% of individuals presenting with QRS alternans, and QRS alternans had a prevalence of 0.037% in the entire population. CONCLUSIONS: WPW alternans is a variant of intermittent WPW, which comprised 2.2% of WPW cases in our pre-participation screening cohort. It does not necessarily indicate a low risk for supraventricular tachycardia. It must be recognized at ECG screening and distinguished from other pathologies that also present with QRS alternans.


FUNDAMENTO: A síndrome de Wolff-Parkinson-White (WPW) é uma condição pró-arrítmica que pode exigir restrição de atividades extenuantes e é caracterizada por sinais de ECG, incluindo ondas delta. Observamos casos de padrões intermitentes de WPW apresentando-se como QRS alternante ('WPW alternante') em uma grande coorte de triagem de ECG pré-participação de homens jovens que se candidataram ao recrutamento militar. OBJETIVOS: Nosso objetivo foi determinar o padrão de WPW alternante, as características do caso e a prevalência de outros diagnósticos diferenciais relevantes apresentando-se como alternância de QRS em um ambiente de pré-participação. MÉTODOS: Cento e vinte e cinco mil cento e cinquenta e oito recrutas militares do sexo masculino prospectivos foram revisados de janeiro de 2016 a dezembro de 2019. Uma revisão de prontuários médicos eletrônicos identificou casos de WPW alternante e padrões ou síndrome de WPW. A revisão de prontuários médicos eletrônicos identificou casos de diagnósticos diferenciais relevantes que podem causar alternância de QRS. RESULTADOS: Quatro indivíduos (2,2%) apresentaram WPW alternante em 184 indivíduos com diagnóstico final de padrão ou síndrome de WPW. Dois desses indivíduos manifestaram sintomas ou achados eletrocardiográficos compatíveis com taquicardia supraventricular. A prevalência geral de WPW alternante foi de 0,003%, e a prevalência de WPW foi de 0,147%. As WPW alternantes representaram 8,7% dos indivíduos com QRS alternantes, e QRS alternantes tiveram prevalência de 0,037% em toda a população. CONCLUSÕES: A WPW alternante é uma variante da WPW intermitente, que compreendeu 2,2% dos casos de WPW em nossa coorte de triagem pré-participação. Não indica necessariamente um baixo risco de taquicardia supraventricular. Deve ser reconhecido na triagem de ECG e distinguido de outras patologias que também apresentam QRS alternantes.


Subject(s)
Tachycardia, Supraventricular , Wolff-Parkinson-White Syndrome , Humans , Male , Diagnosis, Differential , Electrocardiography , Prospective Studies , Wolff-Parkinson-White Syndrome/diagnosis
15.
Biomacromolecules ; 23(10): 4053-4062, 2022 Oct 10.
Article in English | MEDLINE | ID: mdl-36113205

ABSTRACT

The cell walls of parenchyma cells and fibers in bamboo are both highly lignified with secondary thickening. However, the former were found to have much higher nanofibrillation efficiency than fibers via both protocols of ultrasonication and high pressure homogenization. To elucidate the inherent mechanism, detailed comparisons of chemical composition, cell morphology, cell wall density, pore structures, and structural organization of cell wall polymers were performed on native and pretreated cell walls of both parenchyma cells and fibers. Chemical compositional analysis showed that fibers have much higher cellulose (49.8% to 35.5%) but lower xylan content (21.1% to 36.2%) than parenchyma, while their lignin contents were similar (24.9% vs 22.9%). Polarized FTIR further revealed clear differences in the structural organization of polymers between the two types of cells, with all the polymers of fibers being more orderly assembled than those of parenchyma cells. The compact arrangement of polymers in the fibers was also supported by the much higher cell wall density (1.52 vs 1.28 g/cm3) and lower porosity (0.007 vs 0.013 cc/g after chemical pretreatments), as compared to the parenchyma cells. The study provides evidence that the anatomical characteristics of huge cavity-wall ratio, higher cell wall porosity, and less ordered arrangement of cell wall matrix polymers (mainly lignin) in parenchyma cells contribute to their higher nanofibrillation efficiency compared to fibers.


Subject(s)
Lignin , Xylans , Cell Wall/chemistry , Cellulose/metabolism , Lignin/metabolism , Xylans/metabolism
16.
Article in English | MEDLINE | ID: mdl-36141973

ABSTRACT

Regionally coordinated green development has been widely documented in China. However, most previous studies have investigated it from the perspective of linearity, while the spatial correlation of green development is nonlinear. Based on 48 cities in Bohai Rim, this study used a social network analysis to measure the spatial network, with an emphasis on the internal structure of regional green development, and analyzed the driving factors of regionally coordinated green development from the perspective of nonlinearity. We found that large cities have formed a "siphon effect" and that the polarization of eco-efficiency has become increasingly serious. There are limited connections, some of which are redundant, in the spatial network of green development, while the stability of the network is strong. Additionally, reducing the differences in environmental regulation approaches among cities can have a positive impact on the spatial correlation and spillover effect of green development, thereby promoting regionally coordinated green development among cities in the Bohai Rim.


Subject(s)
Efficiency , Social Network Analysis , China , Cities , Economic Development
17.
Front Microbiol ; 13: 899801, 2022.
Article in English | MEDLINE | ID: mdl-35847123

ABSTRACT

Understanding microbial communities associated with bulk and rhizosphere soils will benefit the maintenance of forest health and productivity and the sustainable development of forest ecosystems. Based on MiSeq sequencing, we explored the differences between the bulk soil and the rhizosphere soil on bacterial and fungal communities of pecan plantation. Results suggested that rhizosphere-associated fungal rather than bacterial community structures differed from bulk soil, and rhizosphere soil had lower fungal diversity than bulk soil. Actinobacteria and Cantharellales were the bacterial and fungal biomarkers of the rhizosphere soil of pecan plantation, respectively. In addition, Pleosporales, which are mainly involved in saprophylaxis and plant pathogenic processes, was identified as one of the most important fungal biomarkers for the bulk soil, and the FunGuild predicted a higher relative abundance of pathogenic fungi in bulk soil compared to rhizosphere soil. The pH, ammonium nitrogen ( NH 4 + -N), nitrate nitrogen ( NO 3 - -N), and total carbon (TC) contents drove microbial community structure and composition. The bacterial network was simpler in the rhizosphere soil than in the bulk soil. However, fungi showed the opposite network pattern. Keystone species in bacterial and fungal networks were mostly involved in nutrient cycling and the C cycling, and were found to be enriched in the rhizosphere soil. Overall, in terms of bacterial and fungal communities, the rhizosphere soil behaves more healthily than the bulk soil and has a higher potential for nutrient cycling.

18.
Int J Biol Macromol ; 210: 152-160, 2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35500771

ABSTRACT

The development of nanocellulose fibril (NCF)-based films for use in food packaging has aroused tremendous attention because of their good biodegradability. In this work, NCFs isolated from bamboo parenchyma cell were used to fabricate the composite film with embedded silver nanoparticles (AgNPs). Results demonstrate that the low content of AgNPs, especially at content of 0.1 wt% in the composite film could slightly improve the tensile strength and Young's modulus of the composite film by about 11.0%, owing to the reduced thickness of cellulose crystallites and decreased amount of adsorbed water, as well as the increment in crystallinity and the hydrogen-bond intensity confirmed by X-ray diffraction measurement and Fourier transform infrared spectra. On the other hand, high content of AgNPs could enhance antimicrobial activity and thermal stability while showed negligible negative effect on tensile properties. Specifically, the maximum inhibition zone of the composite film (with AgNPs content of 0.1 wt%) was 13.5 ± 0.8 mm against Salmonella typhi (S. typhi) and 7.5 ± 0.3 mm against Escherichia coli (E. coli). The strong antimicrobial activity of NCF-based films highlights their potential as a biodegradable food packaging material.


Subject(s)
Anti-Infective Agents , Metal Nanoparticles , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Escherichia coli , Food Packaging , Metal Nanoparticles/chemistry , Silver/chemistry
19.
Biomacromolecules ; 23(5): 1938-1948, 2022 05 09.
Article in English | MEDLINE | ID: mdl-35226471

ABSTRACT

Bamboo fibers and parenchyma cells, the two dominant types of cells in bamboo, exhibit some interesting differences in cellulose crystalline structures. In the present investigation, we further demonstrated that these structural differences affect their response during ionic liquid (IL) pretreatment and the sugar conversion yield, by tracking their changes in morphology, chemical, and crystalline structures. All of the results pointed to the fact that the cellulose from bamboo fibers exhibited higher recalcitrance to IL pretreatment, with a significantly lower change in crystallinity index, d spacings from the (110) and (11̅0) planes, crystallite sizes, and easier transformation from cellulose I to cellulose II after pretreatment, as compared to that from parenchyma cells. Furthermore, the crystalline parameters of (110) and (11̅0) lattice planes exhibited more changes compared to the (200) direction. This investigation highlights the significance of parenchyma cell wastes from bamboo processing plants as a competitive candidate for the biorefinery industry.


Subject(s)
Cellulose , Ionic Liquids , Carbohydrates , Cellulose/chemistry , Hydrolysis , Ionic Liquids/chemistry
20.
Carbohydr Polym ; 274: 118653, 2021 Nov 15.
Article in English | MEDLINE | ID: mdl-34702472

ABSTRACT

To better understand the high recalcitrance of bamboo during bioconversion, the fine spatial distribution of polymers in bamboo was studied with Imaging FTIR microscopy under both transmission and ATR modes, combined with PCA data processing. The results demonstrated that lignin, xylan and hydroxycinnamic acid (HCA) were more concentrated in the fibers near the xylem conduit, while cellulose was evenly distributed across the whole fiber sheath. PCA processing produced a clear separation between bamboo fibers and parenchyma cells, indicating that the parenchyma cells contains more pectin and HCA than fibers. It also demonstrated that cellulose, xylan and S-lignin were concentrated most heavily in bamboo fiber secondary cell walls, while G-lignin, pectin and HCA were found more in the compound middle lamella. The revealed information regarding polymer distribution is of great significance for better understanding of the inherent design mechanism of plant cell wall and its efficient utilization.

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