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1.
Carbohydr Polym ; 275: 118683, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34742413

RESUMO

Microbial colonization of catheter surfaces is responsible for most healthcare-associated infections. Quaternized chitin and chitosan have excellent antimicrobial and biocompatible properties and can be used to provide safe and prolonged protection for biomedical catheters. Herein, we prepared quaternized ß-chitin derivative (QC)- and quaternized chitosan derivative (QCS)-based antimicrobial surfaces. The quaternized polysaccharides modified TPU surfaces exhibited hydrophilicity, good biocompatibility. Among these, QCS2-modified TPU exhibited excellent antibacterial properties against Gram-positive and Gram-negative bacteria, and prevented the adherence of bacteria compared with pristine TPU. The antibacterial activity of QCS2-modified surfaces maintained for 8 weeks under the condition of immersion in serum. An in vivo subcutaneous implantation experiment revealed 99.87% reduction of bacteria and reduced expression of inflammation-related factors in the surrounding tissue five days after implantation with QCS2-modified TPU. Therefore, quaternized polysaccharide-modified surfaces have promising potential in preventing medical catheter-associated infections.

2.
BJU Int ; 2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34837315

RESUMO

OBJECTIVE: To investigate the incidence, risk factors, and natural history of parastomal hernia. MATERIALS AND METHODS: We reviewed the records of patients who underwent radical cystectomy and ileal conduit from 2007 to 2020. Patients who had available follow-up CT imaging were included in this study. All CT scans were re-reviewed for detection of parastomal hernia per Moreno-Matias classification. Patients who developed hernia were followed up and classified into stable or progressive (defined as radiologic upgrading and/or need for surgical intervention). Multivariable cox regression was performed to identify independent predictors of hernia development and progression. RESULTS: A total of 361 patients were included in this study. The incidence of radiologic parastomal hernia was 30%, graded as I (56.5%), II (12%), and III (31.5%). Median (IQR) time to radiologic hernia was 8 (5-15) months. During the median (IQR) follow-up of 27 (13-47) months in 108 patients with a hernia, 26% progressed. Median (IQR) time to progression was 12 (6-21) months. On multivariable analysis, female gender (HR 1.86), diabetes (HR 1.81), chronic obstructive pulmonary disease (HR 1.78), and higher body mass index (HR 1.07 for each unit) were independent predictors for radiologic parastomal hernia development. No significant factor was found to be associated with hernia progression. CONCLUSION: The incidence of radiologic parastomal hernia following radical cystectomy and ileal conduit is 30%; a quarter of whom progress in a median time of 12 months. Female gender, diabetes, chronic obstructive pulmonary disease, and high body mass index are independent predictors for radiologic hernia development.

3.
Nanomaterials (Basel) ; 11(11)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34835669

RESUMO

In this paper, an Nb alloying layer on a TC4 alloy was fabricated by using high-current pulsed electron beam (HCPEB) irradiation to improve surface performance. X-ray diffraction (XRD), optical microscopy (OM), laser surface microscope (LSM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the phase composition and microstructure of the surface layer. The microhardness, wear tests and corrosion resistance were also examined. The results show that after HCPEB alloying, a Nb-alloyed layer was formed with about 3.6 µm in thickness on the surface of the sample, which was mainly composed of α'-Ti martensite, ß-Ti equiaxial crystals, and NbTi4 particles. After HCPEB irradiation, the surface hardness, wear resistance and corrosion resistance of Nb alloying layer on TC4 alloy were improved compared to the initial samples.

4.
Eur J Med Chem ; 227: 113966, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34749200

RESUMO

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unprecedented in human history. As a major structural protein, nucleocapsid protein (NPro) is critical to the replication of SARS-CoV-2. In this work, 17 NPro-targeting phenanthridine derivatives were rationally designed and synthesized, based on the crystal structure of NPro. Most of these compounds can interact with SARS-CoV-2 NPro tightly and inhibit the replication of SARS-CoV-2 in vitro. Compounds 12 and 16 exhibited the most potent anti-viral activities with 50% effective concentration values of 3.69 and 2.18 µM, respectively. Furthermore, site-directed mutagenesis of NPro and Surface Plasmon Resonance (SPR) assays revealed that 12 and 16 target N-terminal domain (NTD) of NPro by binding to Tyr109. This work found two potent anti-SARS-CoV-2 bioactive compounds and also indicated that SARS-CoV-2 NPro-NTD can be a target for new anti-virus agents.

5.
Plant Divers ; 43(5): 362-378, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34816062

RESUMO

Eight new species from China, Cheirostylis chuxiongensis, C. yei, Myrmechis lingulata, M. longii, Bulbophyllum ximaense, B. xizangense, B. retusum and B. pulcherissimum, are described and illustrated. Cheirostylis chuxiongensis differs from C. thailandica by having 5-9 irregular and papillae-like calli on each side in the sac of the lip, epichile with entire lobes, petals narrowly obliquely obovate and an apex that is not recurved. Cheirostylis yei is easily distinguished from its relatives similar by having a long stem, pubescent ovary and sepals, epichile lobes with irregular and undulate margins, a subquadrate callus without teeth in the saccate hypochile. Myrmechis lingulata differs from M. chinensis by having a simple and lanceolate to ligulate lip, glabrous bracts and ovary, oblique and narrowly ovate petals. Myrmechis longii differs from M. pumila by having white-veined leaves, oblong-lanceolate epichile lobes, and viscidium attached to the middle of the caudicle. Bulbophyllum ximaense is easily distinguished from its relatives similar by having distant pseudobulbs, shorter scape, an inflorescence with 9-16 orange-red flowers, shorter lateral sepals with a long acuminate apex, incurved and tubular apical margins, a papillate lip disk and triangular-subulate stelidia. Bulbophyllum xizangense is easily distinguished from its relatives similar by having narrow lanceolate leaves, shorter inflorescence with 1-3 greenish-yellow flowers, falcate-ovoid lateral sepals, a lip with small lateral lobes and 3 keels at the base. Bulbophyllum retusum differs from B. spathulatum by having shorter inflorescence, peduncles with 2 tubular sheaths, dorsal sepals with a retuse apex, lateral sepals with lower edges that are connate to each other and free and divergent toward the apex, obovate petals with an acute or slightly retuse apex. Bulbophyllum pulcherissimum differs from B. lopalanthum by its 5-veined dorsal sepal, ovate-lanceolate lateral sepals, obliquely ovate-oblong petal, erose-toothed margins and obovate lip with a large, oblong basal callus, and an obtuse base. In addition, three species (Bulbophyllum frostii, B. raskotii and B. nematocaulon) are reported for the first time in China.

6.
Plant Divers ; 43(5): 379-389, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34816063

RESUMO

Five new species (Gastrochilus yei, Gastrochilus minimus, Luisia simaoensis, Taeniophyllum xizangense, Tuberolabium subulatum) and two newly recorded species (Cleisostoma tricornutum, Luisia inconspicua) of Vandeae (Orchidaceae) from China are described and illustrated. Gastrochilus yei is similar to G. affinis and G. nepalensis, but differs from them by having an epichile not lobed, the apex of the hypochile not bilobed, and a tine on the apex of the leaf. Gastrochilus minimus is similar to G. acinacifolius, but can be distinguished from the latter by having a flabellate epichile that is densely hirsute on the adaxial surface and an inconspicuous central cushion; in addition, the hypochile of G. minimus has a keel that extends to the apex of the epichile. Taeniophyllum xizangense is similar to T. stella and T. radiatum, but it is distinguished from them by having much bigger flowers, inflorescences densely covered with short-bristly hairs, papillae on the external surface of sepals, and bigger triangular-ovate viscidium. Luisia simaoensis is similar to L. magniflora and L. ramosii, but can be easily distinguished from them by having lateral sepals longer than dorsal sepals and petals, lip with irregular and waved margins, and lip with bilobed apex. Luisia inconspicua is moved from Gastrochilus to Luisia based on phylogenetic analyses of plastid matK sequence data. Tuberolabium subulatum is similar to T. carnosum, but it can be easily distinguished from the latter by having an inflorescence much shorter than the leaves, yellow sepals and petals, and many small papillae outside the lip lobes.

7.
Comput Math Methods Med ; 2021: 2867913, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804192

RESUMO

To study the clinical features of infectious mononucleosis (IM) caused by Epstein-Barr virus (EBV) mixed with Mycoplasma pneumonia (MP) or/and cytomegalovirus (CMV)infection, collected 201 hospitalized children who met the IM diagnostic criteria, the clinical manifestations, laboratory tests, complications, treatment, and outcome were compared among EBV infection alone and EBV mixed with MP or/and CMV infection. Most of the children with IM were preschoolers, more frequently occurred in boys than girls. EBV patients with MP had the longest duration of fever. When mixed pathogen infections were involved, the white blood cell count of preschool children was significantly increased, while splenomegaly was more common in older children. In the cases of EBV infection alone, abnormal liver function was positively correlated with age (P = 0.044). Mixed pathogen infections were more common in children with IM, occurring in all age groups, and some clinical characteristics were related to the age of onset and the pathogen of the infection.

8.
Appl Opt ; 60(30): 9570-9577, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34807103

RESUMO

To reduce the number of microcracks and pores on the surface of laser cladding layers, we used a novel, to the best of our knowledge, surface alloying method to modify the surface of a NiCoCrAlY laser cladding coating using high-current pulsed electron beam technology. The x-ray diffraction peaks of the irradiated coatings were affected by the residual stress, which caused the peaks to shift and significantly broaden. With an increase in the number of pulses, the cleaning effect of the coating surface became significant. At the same time, the degree of surface alloying increased, and different degrees of slip were formed on the surface of the coating. There were many nanocrystals accumulated at the slip angle, and the grain size of the coating surface increased.

9.
Anim Nutr ; 7(4): 1024-1030, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34738032

RESUMO

This study aimed to evaluate role of nano-sized zinc (Zn) on lactation performance, health status, and mammary permeability of lactating dairy cows. Thirty multiparous dairy cows with similar days in milk (158 ± 43.2) and body weight (694 ± 60.5 kg) were chosen based on parity and milk production and were randomly assigned to 3 treatment groups: basal diet (control, 69.6 mg/kg of Zn adequate in Zn requirement), basal diet additional Zn-methionine (Zn-Met, providing 40 mg/kg of Zn), and basal diet additional nano-sized Zn oxide (nZnO, providing 40 mg/kg of Zn). The study lasted for 10 wk, with the first 2 wk as adaptation. Feed intake, milk yield and the related variables, and plasma variables were determined every other week. Blood hematological profiles were determined in the 8th week of the study. We found that feed intake, milk yield, and milk composition were similar across the 3 groups. The nZnO- and Zn-Met-fed cows had greater milk Zn concentrations in the milk (3.89 mg/L (Zn-Met) and 3.93 mg/L (nZnO)) and plasma (1.25 mg/L (Zn-Met) and 1.29 mg/L (nZnO)) than the control cows (3.79 mg/L in milk and 1.21 mg/L in plasma). The nZnO-fed cows had higher Zn concentrations in plasma but not in milk compared to Zn-Met-fed cows. The Zn appearance in milk was greater in nZnO-fed (area under curve during the first 4 h post-feeding for milk Zn: 16.1 mg/L) and Zn-Met-fed cows (15.7 mg/L) than in control cows (15.0 mg/L). During the first 4 h post-feeding, milk to blood Zn ratio was greater in nZnO-fed animals but lower in Zn-Met-fed cows compared with control cows. Oxidative stress-related variables in plasma, blood hematological profiles, and mammary permeability related variables were not different across treatments. In summary, lactation performance, Zn concentrations in milk and plasma, hematological profiles, mammary permeability were similar in cows fed nZnO and Zn-Met. We therefore suggested that nZnO feeding can improve Zn bioavailability without impairing lactation performance, health status, and mammary gland permeability in dairy cows.

10.
Virus Res ; 308: 198627, 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34785275

RESUMO

Due to the lack of an adaptive immune system, insects rely on innate immune mechanisms to fight against pathogenic infections. Two major innate immune pathways, Toll and IMD, orchestrate anti-pathogen responses by regulating the expression of antimicrobial peptide (AMP) genes. Although the antifungal or antibacterial function of AMPs has been well characterized, the antiviral role of AMPs in insects remains largely unclear. Periplaneta americana (P. americana), or the American cockroach, is used in traditional Chinese medicine as an antiviral agent; however, the underlying mechanism of action of P. americana extracts is unclear. Our previous study showed that the P. americana genome encodes multiple antimicrobial peptide genes. Based on these data, we predicted five novel P. americana defensins (PaDefensins) and analyzed their primary structure, secondary structure, and physicochemical properties. The putative antiviral, antifungal, antibacterial, and anticancer activities suggested that PaDefensin5 is a desirable therapeutic candidate against viral diseases. As the first experimental evidence of the antiviral effects of insect defensins, we also showed the antiviral effect of PaDefensin5 in Drosophila Kc cells and Drosophila embryos in vivo . In conclusion, results of both in silico predictions and subsequent antiviral experiments suggested PaDefensin5 a promising antiviral drug.

11.
PhytoKeys ; 181: 105-111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34611456

RESUMO

Vacciniummotuoense (Ericaceae), a new species from Motuo County, Xizang Autonomous Region, China is described and illustrated. This new species belongs to Vacciniumsect.Calcicolus and is morphologically most similar to V.dunalianum, but differs in having yellowish-brown tomentose young branches, petioles and inflorescence rachis, leaf blades with 2-3(-4) pairs of secondary veins, usually all basal and with fine veins impressed adaxially and urceolate to spherical corollas.

12.
Chin Med J (Engl) ; 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34593698

RESUMO

BACKGROUND: Female breast cancer (FBC) has become the most prevalent malignancy worldwide. We aimed to evaluate the global and regional burden in epidemiological trends and factors associated with the incidence and mortality of FBC. METHODS: FBC incidence and mortality in 60 selected countries by cancer registry data integrity in 2020 were estimated from the GLOBOCAN database, and their association with the human development index (HDI) was further evaluated. Trends of age-standardized rates of incidence and mortality in 60 countries from 2000 through 2019 were evaluated by joinpoint regression analysis using data of Global Burden of Disease 2019. The association between potential behavioral, metabolic, and socioeconomic risk factor exposure at the nation level retrieved from the World Bank and Global Health Observatory and the incidence and mortality of FBC were evaluated by multivariate linear regression. RESULTS: FBC incidence and mortality varied greatly in the 60 included countries. Higher incidence and mortality rates were typically observed in countries with higher HDIs and vice versa. During 2000 to 2019, significantly increasing trends in incidence and mortality were observed in 26 (average annual percent changes [AAPCs], 0.35-2.96) and nine countries (AAPC, 0.30-1.65), respectively, while significantly decreasing trends in both incidence and mortality were observed in 22 countries, most of which were high-HDI countries. Among the population aged ≥40 years, there were 26 and 11 countries showing significantly increased trends in incidence and mortality, respectively. Ecological analysis showed that countries with higher prevalence rates of high cholesterol and higher health expenditures were more likely to have higher FBC incidence, and countries with higher rates of obesity and poor universal health coverage were more likely to have higher FBC mortality. CONCLUSIONS: Despite decreased or stabilized FBC incidence and mortality rates were observed in some countries with high HDI over the past decades, disease burden became even severer in developing countries, especially for the population aged ≥40 years. Effective targeted preventive programs are strongly encouraged to reduce the FBC disease burden worldwide.

13.
Comput Intell Neurosci ; 2021: 3904273, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34671389

RESUMO

A tunnel boring machine (TBM) is a type of heavy load equipment that is widely used in underground tunnel construction. The geological conditions in the tunneling process are decisive factors that directly affect the control of construction equipment. Because TBM tunneling always takes place underground, the acquisition of geological information has become a key issue in this field. This study focused on the internal relationships between the sequential nature of tunnel in situ data and the continuous interaction between equipment and geology and introduced the long short-term memory (LSTM) time series neural network method for processing in situ data. A method for predicting the geological parameters in advance based on TBM real-time state monitoring data is proposed. The proposed method was applied to a tunnel project in China, and the R 2 of the prediction results for five geological parameters are all higher than 0.98. The performance of the LSTM was compared with that of an artificial neural network (ANN). The prediction accuracy of the LSTM was significantly higher compared with that of the ANN, and the generalization and robustness of LSTM are also better than those of ANN, which indicates that the proposed LSTM method could extract the sequence properties of the in situ data. The rule of equipment-geology interaction was reflected by increasing the memory structure of the model through the introduction of the "gate" concept, and the accurate prediction of geological parameters during tunneling was realized. Additionally, the influence of time window and distance of prediction on the model is discussed. The proposed method provides a new approach toward obtaining geological information during TBM construction and also provides a certain reference for the effective analysis of the in situ data with sequence properties.


Assuntos
Geologia , Redes Neurais de Computação , China , Projetos de Pesquisa
14.
Curr Med Sci ; 41(5): 841-846, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34652629

RESUMO

The purpose of this review is to provide a comprehensive update on recent advances in heart transplantation in China. Despite advances in pharmacologic and device treatment of chronic heart failure, long-term morbidity and mortality remain high, and many patients progress to endstage heart failure. Heart transplantation has become standard treatment for selected patients with end-stage heart failure, though challenges still exist. However, multiple advances over the past few years will improve the survival and quality-of-life of heart transplant recipients. This article elaborates on the specific characteristics of heart transplantation in China, the current issues, development trends, and related experiences with heart transplantation in Wuhan Union Hospital.

16.
BMC Biol ; 19(1): 232, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34711223

RESUMO

BACKGROUND: Flowering plants (angiosperms) are dominant components of global terrestrial ecosystems, but phylogenetic relationships at the familial level and above remain only partially resolved, greatly impeding our full understanding of their evolution and early diversification. The plastome, typically mapped as a circular genome, has been the most important molecular data source for plant phylogeny reconstruction for decades. RESULTS: Here, we assembled by far the largest plastid dataset of angiosperms, composed of 80 genes from 4792 plastomes of 4660 species in 2024 genera representing all currently recognized families. Our phylogenetic tree (PPA II) is essentially congruent with those of previous plastid phylogenomic analyses but generally provides greater clade support. In the PPA II tree, 75% of nodes at or above the ordinal level and 78% at or above the familial level were resolved with high bootstrap support (BP ≥ 90). We obtained strong support for many interordinal and interfamilial relationships that were poorly resolved previously within the core eudicots, such as Dilleniales, Saxifragales, and Vitales being resolved as successive sisters to the remaining rosids, and Santalales, Berberidopsidales, and Caryophyllales as successive sisters to the asterids. However, the placement of magnoliids, although resolved as sister to all other Mesangiospermae, is not well supported and disagrees with topologies inferred from nuclear data. Relationships among the five major clades of Mesangiospermae remain intractable despite increased sampling, probably due to an ancient rapid radiation. CONCLUSIONS: We provide the most comprehensive dataset of plastomes to date and a well-resolved phylogenetic tree, which together provide a strong foundation for future evolutionary studies of flowering plants.

17.
J Healthc Eng ; 2021: 8587351, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34527213

RESUMO

Physical literacy has gained much popularity in educational circles who are working on the improvement of curriculum and overall standard of education. It involves a holistic lifelong comprehensive learning approach that includes movements and physical activities. Overall, it has positive effects on physical, psychological, social, and cognitive health of individuals, so physical literacy exemplifies the dedication to raise a healthier, more active generation. Numerous factors interacting between humanities and social sciences affect the promotion of physical literacy, so such a study will be interdisciplinary which will consider across all social and individual factors. The current research proposes a system dynamic "SD" model to promote students' physical literacy by building a complete causal loop diagram of the model to illustrate the general system. Based on the casual loop diagram, the system is then presented as four subsystems. The model is simulated by allocating 14 different changes of indexes in the physical literacy promotion system to find better allocations for optimal effectiveness in promoting physical literacy. Simulations are carried out by using the Apache Spark architecture utilizing "Big Data" tools for effective, speedy, and reliable analysis and results. The study proposes that different physical literacy indexes in different grades require attention; the optimal promotion of physical literacy can be achieved by increasing the physical knowledge of lower-grade students and increasing the physical attitude of higher-grade students. The model can be used to make decisions about efficient physical literacy management and physical literacy promotion planning.

18.
Cancer Lett ; 522: 255-268, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34563640

RESUMO

Colorectal cancer (CRC) is one of the most common malignancies worldwide. China, Europe and northern America account for more than half of the new CRC cases and associated deaths globally. This review summarizes the current status and temporal trends of CRC in China, Europe, and northern America. The potential primary preventive strategies and latest advances in CRC screening techniques and programs are discussed. Recently, the incidence and mortality of CRC in some European and northern American countries have decreased; conversely, CRC incidence and mortality continue to increase in China. The overall 5-year relative survival rate for CRC is similar between these regions, but there is considerable heterogeneity among European countries. Implementing population-based CRC screening programs can effectively address the growing disease burden. The effectiveness of nationwide CRC screening programs in these regions has been limited by relatively low coverage and participation rate. The deployment of state-of-the-art techniques and precise risk-adapted screening strategies incorporating effective risk prediction models and screening techniques may boost screening effectiveness. Our review provides novel foundations for the development and optimization of CRC preventive strategies.

20.
Carbohydr Polym ; 269: 118270, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34294302

RESUMO

Sustainable bio-based adhesive is a promising substitute for petroleum-based adhesives to alleviate serious environmental and health problems. In this work, a nanoengineered starch-based adhesive was fabricated by grafting vinyl acetate (VAc) onto starch molecule and subsequently incorporating the functional nanoparticle [TiO2-coupling-poly(butyl acrylate, BA), TKB] to overcome the drawbacks present in conventional nanocomposite adhesive. Results showed that the presence of BA altered the surface property of TKB, leading to improved dispersion. In the adhesive with 4% (mass ratio to starch) TKB, TKB aggregates played the role as a sliding bridge, which significantly promoted the storage stability and shear strength in both dry and wet states. Additionally, the latex film with 4% TKB exhibited high compatibility and water resistance due to the promoted hydrophobicity. This study provides a fundamental insight into the improvement of functional nanoparticles on the performance of starch-based adhesive, suggesting a novel strategy for designing high-performance bio-adhesive.

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