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1.
Cell Rep ; 35(5): 109072, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33951426

RESUMO

Visualizing mRNA in real time in vivo at high resolution is critical for a full understanding of the spatiotemporal dynamics of gene regulation and function. Here, using a PP7/PCP-based mRNA-tagging approach, we construct a collection of tissue-specific and differentially expressed toolkit strains for visualizing mRNAs encoding apical, basolateral, and junctional proteins in Caenorhabditis elegans epithelia. We precisely delineate the spatiotemporal organization and dynamics of these transcripts across multiple subcellular compartments and tissues. Remarkably, all the transcripts exhibit an asymmetric, membrane-associated localization during epithelial polarization and maturation, which suggests that mRNA localization is a prerequisite for epithelial polarization and function. Single-particle tracking reveals striking features of the transport dynamics of the mRNAs in a gene-specific, compartment-linked, and time-resolved manner. The toolkit can be used to identify the cis-regulatory elements and trans-acting factors for mRNA localization. This study provides a valuable resource to investigate complex RNA dynamics in epithelial polarity and morphogenesis.

2.
Aerobiologia (Bologna) ; : 1-9, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33967379

RESUMO

To clarify the characteristics and distribution of hospital environmental microbiome associated with confirmed COVID-19 patients. Environmental samples with varying degrees of contamination which were associated with confirmed COVID-19 patients were collected, including 13 aerosol samples collected near eight patients in different wards, five swabs from one patient's skin and his personal belongings, and two swabs from the surface of positive pressure respiratory protective hood and the face shield from a physician who had close contact with one patient. Metagenomic next-generation sequencing (mNGS) was used to analyze the composition of the microbiome. One of the aerosol samples (near patient 4) was detected positive for COVID-19, and others were all negative. The environmental samples collected in different wards possessed protean compositions and community structures, the dominant genera including Pseudomonas, Corynebacterium, Neisseria, Staphylococcus, Acinetobacter, and Cutibacterium. Top 10 of genera accounted for more than 76.72%. Genera abundance and proportion of human microbes and pathogens radiated outward from the patient, while the percentage of environmental microbes increased. The abundance of the pathogenic microorganism of medical supplies is significantly higher than other surface samples. The microbial compositions of the aerosol collected samples nearby the patients were mostly similar to those from the surfaces of the patient's skin and personal belongings, but the abundance varied greatly. The positive rate of COVID-19 RNA detected from aerosol around patients in general wards was quite low. The ward environment was predominantly inhabited by species closely related to admitted patients. The spread of hospital microorganisms via aerosol was influenced by the patients' activity. Supplementary Information: The online version contains supplementary material available at 10.1007/s10453-021-09708-5.

3.
J Ethnopharmacol ; 276: 114180, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33957209

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Berberine (BBR), extracted from the traditional medicinal plant Coptis chinensis Franch., has been widely used for the treatment of type 2 diabetes mellitus (T2DM) and its complications. AIM OF THE STUDY: To determine the potential pharmacological mechanisms underlying BBR therapeutic effect on T2DM and its complications by in silico network pharmacology and experimental in vivo validation. MATERIALS AND METHODS: A predictive network depicting the relationship between BBR and T2DM was designed based on information collected from several databases, namely STITCH, CHEMBL, PharmMapper, TTD, Drugbank, and PharmGKB. Identified overlapping targets related to both BBR and T2DM were crossed with information on biological processes (BPs) and molecular/signaling pathways using the DAVID platform and Cytoscape software. Three candidate targets identified with the BBR-T2DM network (RXRA, KCNQ1 and NR3C1) were evaluated in the C57BL/6J mouse model of T2DM. The mice were treated with BBR or metformin for 10 weeks. Weight, fasting blood glucose (FBG), oral glucose tolerance, and expression levels of the three targets were evaluated. RESULTS: A total of 31 targets of BBR that were also related to T2DM were identified, of which 14 had already been reported in previous studies. Furthermore, these 31 overlapping targets were enriched in 21 related BPs and 18 pathways involved in T2DM treatment. The identified BP-target-pathway network revealed the underlying mechanisms of BBR antidiabetic activity were mediated by core targets such as RXRA, KCNQ1, and NR3C1. In vivo experiments further confirmed that treatment with BBR significantly reduced weight and FBG and alleviated insulin resistance in T2DM mice. Moreover, BBR treatment promoted RXRA expression, whereas it reduced KCNQ1 and NR3C1 expression in the liver. CONCLUSION: Using network pharmacology and a T2DM mouse model, this study revealed that BBR can effectively prevent T2DM symptoms through vital targets and multiple signaling pathways. Network pharmacology provides an efficient, time-saving approach for therapeutic research and the development of new drugs.

4.
Phys Chem Chem Phys ; 23(18): 10763-10767, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33928338

RESUMO

Here, we show that molecular N2 was efficiently captured by organic arylium cations in a well-defined manner at ambient pressure and temperature, which was monitored by on-line mass spectrometry analysis. A kinetic picture was proposed to disclose the principle of the ion-molecule reaction behavior for exclusive aryldiazonium production. The observation has an implication for direct nitrogen fixation into an organic framework via the intermediacy of such cationic species.

5.
Sensors (Basel) ; 21(8)2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33921068

RESUMO

Knowledge Distillation (KD), which transfers the knowledge from a teacher to a student network by penalizing their Kullback-Leibler (KL) divergence, is a widely used tool for Deep Neural Network (DNN) compression in intelligent sensor systems. Traditional KD uses pre-trained teacher, while self-KD distills its own knowledge to achieve better performance. The role of the teacher in self-KD is usually played by multi-branch peers or the identical sample with different augmentation. However, the mentioned self-KD methods above have their limitation for widespread use. The former needs to redesign the DNN for different tasks, and the latter relies on the effectiveness of the augmentation method. To avoid the limitation above, we propose a new self-KD method, Memory-replay Knowledge Distillation (MrKD), that uses the historical models as teachers. Firstly, we propose a novel self-KD training method that penalizes the KD loss between the current model's output distributions and its backup outputs on the training trajectory. This strategy can regularize the model with its historical output distribution space to stabilize the learning. Secondly, a simple Fully Connected Network (FCN) is applied to ensemble the historical teacher's output for a better guidance. Finally, to ensure the teacher outputs offer the right class as ground truth, we correct the teacher logit output by the Knowledge Adjustment (KA) method. Experiments on the image (dataset CIFAR-100, CIFAR-10, and CINIC-10) and audio (dataset DCASE) classification tasks show that MrKD improves single model training and working efficiently across different datasets. In contrast to the existing fancy self-KD methods with various external knowledge, the effectiveness of MrKD sheds light on the usually abandoned historical models during the training trajectory.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33887157

RESUMO

Background: It is widely acknowledged that pathogenic germs delay wound healing to some extent. To explore factors influencing the wound healing process, the current study was conducted to evaluate the antibacterial effect of topical application of copper sulfide nanoparticles (CuS NPs) in vitro and on infected wound healing process in the rat model. Materials and Methods: In this study, the morphology and size of CuS NPs were detected. Staphylococcus aureus and Escherichia coli were used so that the antibacterial ability of CuS NPs could be evaluated better. In addition, a 2-cm circular full-thickness wound infected with a solution of 107 colony forming units (CFU) Staphylococcus aureus was created on the back of each rat. The rats were divided into four groups including the control group, the 100 mcg/mL CuS NPs group, the 250 mcg/mL CuS NPs group, and the 500 mcg/mL CuS NPs group. Tissue bacterial count and histologic assessment were evaluated. Results: The results indicated that CuS NPs had antibacterial activity against Staphylococcus aureus and Escherichia coli. Moreover, they could decrease the incidence of bacterial colonization and promote wound healing through re-epithelialization and collagen deposition. Furthermore, CuS NPs could maintain Cu2+ continuous release and inhibit the viability of Staphylococcus aureus through lipid peroxidation. Conclusions: This study found that CuS NPs have fine antibacterial properties, and particularly, the 500 mcg/mL CuS NPs had better effects, without increase of side effects. They could promote infected wound healing, the prospective clinical application of which was further confirmed in the treatment of wound infection.

7.
Mar Pollut Bull ; 167: 112292, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33873041

RESUMO

The effects of multiple natural and anthropogenic stressors on the functional trait composition and diversity of marine macrobenthic communities in Laoshan Bay were investigated using biological trait analysis (BTA). Seven traits, including 27 trait modalities and four functional diversity indices (functional richness, functional evenness, functional divergence, and Rao's quadratic entropy), were considered. The results of RLQ (environmental variables (R), species taxa (L), and traits (Q)) and variance partitioning analysis (VPA) showed that the trait compositions and functional diversity of macrobenthic communities were influenced by a combination of stressors, among which heavy metals were the major factors. At the sites with high heavy metal pollution, the prevalent traits were infauna, burrower, and deposit feeder, whereas epifauna, carnivores and crawlers were dominant at the sites of low heavy metal contamination. The impact of natural environmental gradients on macrobenthic communities is also worthy of attention.

8.
CNS Neurosci Ther ; 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33838005

RESUMO

AIMS: Peripheral nerve defects are often difficult to recover from, and there is no optimal repair method. Therefore, it is important to explore new methods of repairing peripheral nerve defects. This study explored the efficacy of nerve grafts constructed from chitin biological conduits combined with small autogenous nerves (SANs) and platelet-rich plasma (PRP) for repairing 10-mm sciatic nerve defects in rats. METHODS: To prepare 10-mm sciatic nerve defects, SANs were first harvested and PRP was extracted. The nerve grafts consisted of chitin biological conduits combined with SAN and PRP, and were used to repair rat sciatic nerve defects. These examinations, including measurements of axon growth efficiency, a gait analysis, electrophysiological tests, counts of regenerated myelinated fibers and observations of their morphology, histological evaluation of the gastrocnemius muscle, retrograde tracing with Fluor-Gold (FG), and motor endplates (MEPs) distribution analysis, were conducted to evaluate the repair status. RESULTS: Two weeks after nerve transplantation, the rate and number of regenerated axons in the PRP-SAN group improved compared with those in the PRP, SAN, and Hollow groups. The PRP-SAN group exhibited better recovery in terms of the sciatic functional index value, composite action potential intensity, myelinated nerve fiber density, myelin sheath thickness, and gastrectomy tissue at 12 weeks after transplantation, compared with the PRP and SAN groups. The results of FG retrograde tracing and MEPs analyses showed that numbers of FG-positive sensory neurons and motor neurons as well as MEPs distribution density were higher in the PRP-SAN group than in the PRP or SAN group. CONCLUSIONS: Nerve grafts comprising chitin biological conduits combined with SANs and PRP significantly improved the repair of 10-mm sciatic nerve defects in rats and may have therapeutic potential for repairing peripheral nerve defects in future applications.

9.
Ying Yong Sheng Tai Xue Bao ; 32(3): 1069-1079, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33754574

RESUMO

Based on seasonal bottom trawl surveys in November 2015 (autumn), February (winter), May (spring) and August (summer) in 2016, the index of relative importance (IRI), Shannon index and Pianka index were used to analyze the breadth and overlap of spatio-temporal niche of major fish species in the Pishan waters off Zhejiang Province. Redundancy analysis and interspecific competition coefficient were used to examine the competition relationship and niche differentiation of those major fish species. The results showed that a total of 61 fish species were recorded throughout the year, which belonged to 13 orders, 29 families and 48 genera. A total of 19 species with IRI>100 were identified as major fish species. The temporal niche overlap value between Chelidonichthys kumu and Atule kalla was largest, indicating high temporal synchronization. Both the spatial niche overlap value and the spatio-temporal niche overlap value between Trpauchen vagina and Cynoglossus interruptus were largest, indicating that their spatial homology was high and that the use of spatial and temporal two-dimensional resource of both species were consistent. The percentage of species pairs with spatio-temporal niche overlap at the significant level (Qik>0.6) was only 5.8% in Pishan waters, indicating that the spatial and temporal distribution of those species were quite different. The overlap of spatio-temporal niche significantly varied across different seasons. The results of the interspecific competition coefficient were basically consistent with the niche overlap. Results of the redundancy analysis revealed the relationships between major fish species and environmental factors (temperature, salinity, dissolved oxygen), and further explained the niche diffe-rentiation among species.


Assuntos
Ecossistema , Peixes , Animais , China , Humanos , Salinidade , Estações do Ano
10.
Artigo em Inglês | MEDLINE | ID: mdl-33650052

RESUMO

Evidence on the short-term effects of ambient air pollution on chronic obstructive pulmonary disease (COPD) mortality is still not conclusive. The aim of this study was to investigate the relationships between them in Wuhan China. Daily death numbers, concentrations of air pollutants (PM2.5, PM10, SO2, NO2, and O3), and meteorological characteristics in Wuhan from January 1, 2014, to December 31, 2019, were collected. Time-series analysis using generalized additive model was applied. The results showed that a total of 16,150 deaths (7.37 deaths per day) from COPD were observed. The daily average concentrations of PM2.5, PM10, SO2, NO2, and O3 were 59.03, 90.48, 12.91, 48.84, and 91.77 µg/m3, respectively. In single pollutant model, for every increase of 10 µg/m3 in PM10, SO2, and NO2 levels, COPD mortality increased by 0.583% (95% CI: 0.055-1.113%), 4.299% (95% CI: 0.978-7.729%), and 1.816% (95% CI: 0.515-3.313%) at lag03, respectively. No significant associations were found for PM2.5 and O3. Subgroup analysis demonstrated that females were more susceptible to PM2.5, PM10, SO2, and NO2. The concentrations of PM10, SO2, and NO2 were significantly associated with COPD mortality for older adults. The effects of PM2.5 and O3 on COPD mortality were higher in warm period. In two-pollutant models, the significantly positive associations between SO2 and NO2 and COPD mortality remained after adjusting for PM2.5 or O3. In conclusions, short-term exposure to PM10, SO2, and NO2 are significantly associated with a higher risk of COPD mortality. Female or elderly are more susceptible to air pollution. It is urgent to implement the environmental protection policy.

11.
Anal Chem ; 93(12): 5248-5258, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33739820

RESUMO

Urine is a noninvasive biofluid that is rich in polar metabolites and well suited for metabolomic epidemiology. However, because of individual variability in health and hydration status, the physiological concentration of urine can differ >15-fold, which can pose major challenges in untargeted liquid chromatography-mass spectrometry (LC-MS) metabolomics. Although numerous urine normalization methods have been implemented (e.g., creatinine, specific gravity-SG), most are manual and, therefore, not practical for population-based studies. To address this issue, we developed a method to measure SG in 96-well-plates using a refractive index detector (RID), which exhibited accuracy within 85-115% and <3.4% precision. Bland-Altman statistics showed a mean deviation of -0.0001 SG units (limits of agreement: -0.0014 to 0.0011) relative to a hand-held refractometer. Using this RID-based SG normalization, we developed an automated LC-MS workflow for untargeted urinary metabolomics in a 96-well-plate format. The workflow uses positive and negative ionization HILIC chromatography and acquires mass spectra in data-independent acquisition (DIA) mode at three collision energies. Five technical internal standards (tISs) were used to monitor data quality in each method, all of which demonstrated raw coefficients of variation (CVs) < 10% in the quality controls (QCs) and < 20% in the samples for a small cohort (n = 87 urine samples, n = 22 QCs). Application in a large cohort (n = 842 urine samples, n = 248 QCs) demonstrated CVQC < 5% and CVsamples < 16% for 4/5 tISs after signal drift correction by cubic spline regression. The workflow identified >540 urinary metabolites including endogenous and exogenous compounds. This platform is suitable for performing urinary untargeted metabolomic epidemiology and will be useful for applications in population-based molecular phenotyping.

12.
BMC Bioinformatics ; 22(1): 127, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33731020

RESUMO

BACKGROUND: An increasing number of clinical trials require biomarker-driven patient stratification, especially for revolutionary immune checkpoint blockade therapy. Due to the complicated interaction between a tumor and its microenvironment, single biomarkers, such as PDL1 protein level, tumor mutational burden (TMB), single gene mutation and expression, are far from satisfactory for response prediction or patient stratification. Recently, combinatorial biomarkers were reported to be more precise and powerful for predicting therapy response and identifying potential target populations with superior survival. However, there is a lack of dedicated tools for such combinatorial biomarker analysis. RESULTS: Here, we present dualmarker, an R package designed to facilitate the data exploration for dual biomarker combinations. Given two biomarkers, dualmarker comprehensively visualizes their association with drug response and patient survival through 14 types of plots, such as boxplots, scatterplots, ROCs, and Kaplan-Meier plots. Using logistic regression and Cox regression models, dualmarker evaluated the superiority of dual markers over single markers by comparing the data fitness of dual-marker versus single-marker models, which was utilized for de novo searching for new biomarker pairs. We demonstrated this straightforward workflow and comprehensive capability by using public biomarker data from one bladder cancer patient cohort (IMvigor210 study); we confirmed the previously reported biomarker pair TMB/TGF-beta signature and CXCL13 expression/ARID1A mutation for response and survival analyses, respectively. In addition, dualmarker de novo identified new biomarker partners, for example, in overall survival modelling, the model with combination of HMGB1 expression and ARID1A mutation had statistically better goodness-of-fit than the model with either HMGB1 or ARID1A as single marker. CONCLUSIONS: The dualmarker package is an open-source tool for the visualization and identification of combinatorial dual biomarkers. It streamlines the dual marker analysis flow into user-friendly functions and can be used for data exploration and hypothesis generation. Its code is freely available at GitHub at  https://github.com/maxiaopeng/dualmarker under MIT license.


Assuntos
Biomarcadores Tumorais , Neoplasias da Bexiga Urinária , Biomarcadores Tumorais/genética , Ensaios Clínicos como Assunto , Humanos , Mutação , Resultado do Tratamento , Microambiente Tumoral
13.
Aging (Albany NY) ; 13(5): 7549-7569, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33686024

RESUMO

Ginseng has been used for the treatment of aging and memory impairment for thousands of years. Several studies have found that ginsenoside Rg1, as one of the main active components of ginseng, could potentially improve cognitive function in several different animal models. A preclinical systematic review to evaluate the efficacy and mechanisms of ginsenoside Rg1 for ameliorating cognitive impairments in Alzheimer's disease is reported here. We searched six databases from their inceptions to January 2019. Thirty-two studies were selected, which included a total of 1,643 animals. According to various cognitive behavioral tests, the results of the meta-analyses showed that ginsenoside Rg1 significantly improved cognitive behavioral impairments in most Alzheimer's disease models (P < 0.05), but there were no significant effects in animals with neuronal degeneration induced by chronic stress or in SAMP8 transgenic mice. The potential mechanisms included antioxidant and anti-inflammatory effects, amelioration of Alzheimer's disease-related pathology, synapse protection, and up-regulation of nerve cells via multiple signaling pathways.

14.
Catheter Cardiovasc Interv ; 97 Suppl 2: 1009-1015, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33689212

RESUMO

OBJECTIVE: The present study compared 10-year clinical outcomes between transradial access (TRA) and transfemoral access (TFA) for left main (LM) percutaneous coronary intervention (PCI). BACKGROUND: There are limited data regarding the long-term safety and efficacy of TRA for LM PCI. METHODS: This retrospective study evaluated consecutive patients who underwent unprotected LM PCI between January 2004 and December 2008 at Fu Wai Hospital. The exclusion criteria were age of less than 18 years and presentation with acute myocardial infarction. The primary endpoint was major adverse cardiac or cerebrovascular events (MACCE), which was defined as a composite of all-cause death, myocardial infarction, stroke, and any revascularization at the 10-year follow-up. RESULTS: Among 913 eligible patients, TRA was used for 417 patients (45.7%) and TFA was used for 496 patients (54.3%). The 30-day clinical outcomes were similar between the two groups. Results from the 10-year follow-up revealed that MACCE occurred in 180 patients (46.7%) from the TRA group and in 239 patients (51.2%) from the TFA group (log-rank p = .3). The TRA and TFA groups also had low and comparable cumulative rates of all-cause death (14.6% vs. 17.3%, log-rank p = .56) and cardiac death (7.9% vs. 9.1%, log-rank p = .7). CONCLUSION: The present study revealed no significant differences in long-term clinical outcomes when TRA or TFA were used for LM PCI.

15.
Sensors (Basel) ; 21(5)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668138

RESUMO

While growing instruments generate more and more airborne or satellite images, the bottleneck in remote sensing (RS) scene classification has shifted from data limits toward a lack of ground truth samples. There are still many challenges when we are facing unknown environments, especially those with insufficient training data. Few-shot classification offers a different picture under the umbrella of meta-learning: digging rich knowledge from a few data are possible. In this work, we propose a method named RS-SSKD for few-shot RS scene classification from a perspective of generating powerful representation for the downstream meta-learner. Firstly, we propose a novel two-branch network that takes three pairs of original-transformed images as inputs and incorporates Class Activation Maps (CAMs) to drive the network mining, the most relevant category-specific region. This strategy ensures that the network generates discriminative embeddings. Secondly, we set a round of self-knowledge distillation to prevent overfitting and boost the performance. Our experiments show that the proposed method surpasses current state-of-the-art approaches on two challenging RS scene datasets: NWPU-RESISC45 and RSD46-WHU. Finally, we conduct various ablation experiments to investigate the effect of each component of the proposed method and analyze the training time of state-of-the-art methods and ours.

16.
Ying Yong Sheng Tai Xue Bao ; 32(2): 453-466, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33650354

RESUMO

The Quaternary sediment in the Ningbo Coastal Plain was the deposit due to sea-land interaction, which recorded information of past climate changes. The region is therefore an ideal area to study paleoclimate changes and sedimentary characteristics. We determined the stratigraphic division and paleoenvironmental evolution based on 14C and paleomagnetic dating, along with detailed analyses of lithology, pollen assemblage, foraminifera and ostracodes assemblage, and grain size of sediment in core Z02 located in the southeastern Ningbo Coastal Plain. The results showed that the boundary between the Holocene and Upper Pleistocene in the core Z02 record was at 30.5 m, the boundary between the Upper and Middle Pleistocene was at 82.65 m, and the boundary between the Quaternary and Lower Cretaceous was at 90 m. The Middle Pleistocene section of the core contained few sediments, while the Lower Pleistocene section was completely missed. During the late Pleistocene, the hydrodynamic conditions experienced energy levels of medium to medium low to medium, and sedimentary facies changed from alluvial lake to overbank to river to lake to alluvial lake to lake to overbank. During the Holocene, the hydrodynamic changes experienced energy levels of medium low to low to medium, and the sedimentary facies changed from shoreland to shallow sea to shoreland lake. The Ningbo Coastal Plain had experienced tectonic uplift, weathering and erosion stage in the Early and Middle Pleistocene, from warm and humid to dry in the Late Pleistocene, and from warm and humid to dry and cool in the Holocene, as revealed by the core Z02 record. This study provided useful information in investigating past environmental changes in the subtropical coastal region of eastern China.


Assuntos
Lagos , Rios , China , Mudança Climática , Sedimentos Geológicos
17.
Vaccines (Basel) ; 9(2)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670199

RESUMO

Zika virus (ZIKV) infections have been associated with an increased incidence of severe microcephaly and other neurodevelopmental disorders in newborn babies. Passive immunization with anti-ZIKV neutralizing antibodies has the potential to become a feasible treatment or prophylaxis option during pregnancy. Prior to clinical use, such antibodies should be assessed for their ability to block ZIKV passage to the fetus. We used human placental and mammalian cell monolayers that express FcRn and laboratory preparations of anti-ZIKV antibodies as a model system to investigate the disposition of ZIKV/antibody immune complexes (ICs) at the maternal-fetal interface. We further characterized solution properties of the ICs to evaluate whether these are related to in vitro effects. We found that both ZIKV and ZIKV envelope glycoprotein can enter and passage through epithelial cells, especially those that overexpress FcRn. In the presence of ZIKV antibodies, Zika virus entry was bimodal, with reduced entry at the lowest (0.3-3 ng/mL) and highest (µg/mL) antibody concentrations. Intermediate concentrations attenuated inhibition or enhanced viral entry. With respect to anti-ZIKV antibodies, we found that their degradation was accelerated when presented as ICs containing increased amounts of ZIKV immunogen. Of the two monoclonal antibodies tested, the preparation with higher aggregation also exhibited higher degradation. Our studies confirm that intact Zika virus and its envelope immunogen have the potential to enter and be transferred across placental and other epithelial cells that express FcRn. Presence of anti-ZIKV IgG antibodies can either block or enhance cellular entry, with the antibody concentration playing a complex role in this process. Physicochemical properties of IgG antibodies can influence their degradation in vitro.

18.
Pathogens ; 10(2)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671750

RESUMO

Melophagus ovinus (sheep ked) is a hematophagous ectoparasite that mainly parasitizes sheep. In addition to causing inflammation, wool loss, and skin damage to the animal hosts, M. ovinus also serves as a vector for a variety of pathogens and is highly likely to participate in the life and transmission cycle of pathogenic organisms. Herein, we investigated the presence and molecular characterization of vector-borne pathogens in M. ovinus from Qinghai-Tibet Plateau, China. A total of 92 M. ovinus pools collected from the Qinghai province of China were screened for the presence of selected vector-borne pathogens. The overall positive rate of A. ovis, A. bovis, A. phagocytophilum, and T. ovis in M. ovinus was 39.1%, 17.4%, 9.8%, and 89.1%, respectively. All of the samples were negative for Border disease virus (BDV), other Anaplasma species, Babesia spp., Rickettsia spp., and Borrelia spp. Co-infection of different Anaplasma species and T. ovis occurred in 51.2% of all samples with T. ovis. The positive rates of A. ovis, A. bovis, and A. phagocytophilum in different regions and altitudes of the sampling sites were significantly different. Sequence and phylogenetic analysis of target genes confirmed their identity with corresponding pathogens. Our results elucidate the occurrence and molecular characterization of Anaplasma spp. and Theileria spp. in M. ovinus, which could act as potential zoonotic reservoirs. To the best of our knowledge, this is the first report of the detection of A. bovis and A. phagocytophilum DNA in M. ovinus. This study gives the first extensive molecular survey of vector-borne pathogens with veterinary and public health significance in M. ovinus from the Qinghai-Tibet Plateau, China.

19.
Zhongguo Gu Shang ; 34(2): 153-6, 2021 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-33666003

RESUMO

OBJECTIVE: To investigate specific technique and clinical effects of closed folding top consolidation maneuver combined with splint fixation maneuver for consolidation and cedar bark external fixation splint for the treatment of double fractures of distal ulna and radius in children. METHODS: From January 2017 to December 2019, 17 children with double fractures of distal ulna and radius were treated with closed folded apex consolidation maneuver, including 13 males and 4 females, aged from 4 to 11 years old with an average of (7.29±2.34) years old. The fractures were fixed with cedar bark splint and followed up for 6 months, and alignment of fracture was evaluated according to the latest X-rays by follow up, and function of the affected limbs was evaluated by Anderson forearm function evaluation criteria. RESULTS: Fifteen of 17 children were successfully reset immediately, and 2 children were successfully reset again. The average fixed time was (25.00±3.35) days. At 6 months of follow up, 12 patients got excellent results, 3 good, 2 fair, and 0 poor according to Anderson forearm function evaluation criteria. The position of all children were larger than 3/4, and 10 children were received anatomical reduction, alignment of 4 children was less than 10°, 3 children was less than 15°. No complications such as fracture displacement, nonunion, compartment syndrome, and forearm rotation dysfunction occurred. CONCLUSION: Restoration of distal radius double fracture in children with the combination of the closed folding and top fixation maneuver and splint fixation maneuver has advantages of higher success rate, lower complications, which could reduce operating difficultyand pain of patients.


Assuntos
Fraturas do Rádio , Fraturas da Ulna , Idoso , Criança , Pré-Escolar , Feminino , Fixação de Fratura , Fixação Interna de Fraturas , Humanos , Masculino , Rádio (Anatomia) , Fraturas do Rádio/terapia , Contenções , Resultado do Tratamento , Ulna
20.
Zool Res ; 42(2): 250-251, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33738990

RESUMO

Following the publication of our paper (Zhang et al., 2020), it has come to our attention that we erroneously listed two funding sources unrelated to this study in the "ACKNOWLEDGEMENTS" section. Hereby, we wish to update the "ACKNOWLEDGEMENTS" section as a correction.

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