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1.
Rev Sci Instrum ; 92(1): 015001, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33514244

RESUMO

A simple systematic calibration method based on acceleration and angular rate measurements is introduced for the fiber-optic gyro strapdown inertial navigation system in this paper. Meanwhile, a unified mathematical framework and an iterative calculation method are designed for the systematic calibration method. Using this method, one can estimate the fiber-optic gyro inertial measurement unit (FOG IMU) parameters both at a manufacturer's facility and in the field. In order to get all FOG IMU parameters, a procedure adopted based on this approach consists of two stages: First, FOG IMU raw data (accelerometer and gyro readouts) are accumulated in 19 specified FOG IMU positions. Second, the accumulated data are processed by special software to estimate all FOG IMU parameters. In addition, observability analysis of the method in 19 specified FOG IMU positions is done without the limitation of FOG IMU's initial orientation, and this analysis provides theoretical support for the application in a complex terrain. Moreover, the influence of gravity disturbance is analyzed for the first time. The analysis and experiment results show that the systematic calibration method provided by this work can meet the requirement of FOG IMU calibration.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 246: 118944, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33007643

RESUMO

To explore the biological properties of rosin derivatives, two dehydroabietic acid derivatives N-(5-dehydroabietyl-1,3,4-thiadiazole)-yl-pyridine-2-carboxamide (DTPC) and di-N-(5-dehydroabietyl-1,3,4-thiadiazole)-yl-pyridine-2,6-carboxamide (DDTPC) with 1,3,4-thiadiazole, pyridine and amide moieties were designed and synthesized according to superposition principle of activity group. They interact with calf thymus DNA (CT DNA) via intercalation based on the results of circular dichroism (CD) and fluorescence spectroscopy, DNA denaturation and viscosity studies. Fluorescence and CD spectral experiments indicate that they might be transported and stored by protein like bovine serum albumin (BSA). MTT assay was further carried out to examine their cytotoxicity, they both showed selective cytotoxicity and DTPC exhibited better cytotoxicity. The antiproliferative effect of DTPC toward A431 cell line was stronger than that of clinically used cisplatin and oxaliplatin. In addition, the cytotoxicity of DTPC and DDTPC was closely related with their DNA binding ability.

3.
Genomics ; 113(2): 456-462, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33383142

RESUMO

T-cell receptor (TCR) is crucial in T cell-mediated virus clearance. To date, TCR bias has been observed in various diseases. However, studies on the TCR repertoire of COVID-19 patients are lacking. Here, we used single-cell V(D)J sequencing to conduct comparative analyses of TCR repertoire between 12 COVID-19 patients and 6 healthy controls, as well as other virus-infected samples. We observed distinct T cell clonal expansion in COVID-19. Further analysis of VJ gene combination revealed 6 VJ pairs significantly increased, while 139 pairs significantly decreased in COVID-19 patients. When considering the VJ combination of α and ß chains at the same time, the combination with the highest frequency on COVID-19 was TRAV12-2-J27-TRBV7-9-J2-3. Besides, preferential usage of V and J gene segments was also observed in samples infected by different viruses. Our study provides novel insights on TCR in COVID-19, which contribute to our understanding of the immune response induced by SARS-CoV-2.

4.
J Agric Food Chem ; 69(1): 474-482, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33372794

RESUMO

In this work, spiral dextrin/resveratrol (SD/Res) crystal, a new colon-specific drug-delivery system, was established by a novel method of encapsulation and cocrystallization to improve the antidigestion ability compared with the SD/Res inclusion complex (SD/Res IC) prepared by encapsulation and coprecipitation. X-ray diffraction (XRD) and scanning electron microscopy (SEM) revealed that the SD/Res crystal formed a more regular and perfect crystallite than SD/Res IC. Moreover, the encapsulation ability and thermostability of the SD/Res crystal were enhanced as the chain length of SD was increased. In vitro digestion indicated that SD/Res IC merely achieved small intestine-targeted release of resveratrol, while the SD/Res crystal could act as a colon-specific delivery system to protect resveratrol from degradation by gastric acid and pancreatic enzymes. The SD-1/Res crystal presented much higher thermal stability and stronger gastrointestinal stability than other SD/Res crystals and SD/Res ICs, which facilitated its application as a novel colon-target delivery system for resveratrol.

5.
Brain Behav ; : e01957, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33274855

RESUMO

OBJECTIVES: Surgical treatment is expected to remove clot immediately in acute spontaneous intracerebral hemorrhage (SICH) patients. The aim of this study was to evaluate whether Naoxueshu could enhance the efficacy of clot removal surgery in acute SICH patients. METHODS: One hundred twenty patients who had been diagnosed as SICH according to neuroimaging were enrolled in this study. They received craniotomy, decompressive craniectomy, or minimally invasive surgical evacuation as appropriate and then were randomized into two groups: the Naoxueshu group (NXS group, n = 60) and the control group (n = 60). All the patients received standard medical management while patients in NXS group also took Naoxueshu oral liquid 10 ml with three times a day for seven consecutive days. The primary outcome was the 7-day hematoma volume and secondary outcomes were 7-day National Institutes of Health Stroke Scale (NIHSS) score and 7-day cerebral edema score. RESULTS: After clot removal surgery, hematoma volume in NXS group (9.5 ± 8.0) was significantly decreased than that in Control group (21.3 ± 22.9, p < .0001) 7 days after surgery. Moreover, cerebral edema was also relieved after 7-day's Naoxueshu treatment (2.5 ± 0.9 vs. 2.9 ± 0.7, p = .043). Since patients in NXS group had worse baseline NIHSS score (17.2 ± 8.1 vs. 13.7 ± 10.1, p = .039), it was reasonable to conclude that Naoxueshu treatment could improve patients' neurological function because 7-day NIHSS score of the two groups was similar. CONCLUSION: Naoxueshu oral liquid could relieve hematoma volume and cerebral edema after clot removal surgery in acute SICH patients. Moreover, it had the potential to improve patients' short-term neurological function.

6.
Bioinformatics ; 2020 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-33367627

RESUMO

MOTIVATION: The Golgi apparatus has a key functional role in protein biosynthesis within the eukaryotic cell with malfunction resulting in various neurodegenerative diseases. For a better understanding of the Golgi apparatus, it is essential to identification of sub-Golgi protein localization. Although some machine learning methods have been used to identify sub-Golgi localization proteins by sequence representation fusion, more accurate sub-Golgi protein identification is still challenging by existing methodology. RESULTS: we developed a protein sub-Golgi localization identification protocol using deep representation learning features with 107 dimensions. By this protocol, we demonstrated that instead of multi-type protein sequence feature representation fusion as in previous state-of-the-art sub-Golgi-protein localization classifiers, it is sufficient to exploit only one type of feature representation for more accurately identification of sub-Golgi proteins. Compared with independent testing results for benchmark datasets, our protocol is able to perform generally, reliably, and robustly for sub-Golgi protein localization prediction. AVAILABILITY: A use-friendly webserver is freely accessible at http://isGP-DRLF.aibiochem.net and the prediction code is accessible at https://github.com/zhibinlv/isGP-DRLF. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

7.
PeerJ ; 8: e9675, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33194342

RESUMO

Objective: To explore the relationship between body mass index (BMI) and clinicopathological characteristics in patients with papillary thyroid carcinoma (PTC). Methods: The clinical data of 1,579 patients with PTC, admitted to our hospital from May 2016 to March 2017, were retrospectively analyzed. According to the different BMI of patients, it can be divided into underweight recombination (BMI < 18.5 kg/m), normal body recombination (18.5 ≤ BMI < 24.0 kg/m2), overweight recombination (24.0 ≤ BMI < 28.0 kg/m2) and obesity group (BMI ≥ 28.0 kg/m2). The clinicopathological characteristics of PTC in patients with different BMIs group were compared. Results: In our study, the risk for extrathyroidal extension (ETE), advanced T stage (T III/IV), and advanced tumor-node-metastasis stage (TNM III/IV) in the overweight group were higher, with OR (odds ratio) = 1.99(1.41-2.81), OR = 2.01(1.43-2.84), OR = 2.94(1.42-6.07), respectively, relative to the normal weight group. The risk for ETE and T III/IV stage in the obese group were higher, with OR = 1.82(1.23-2.71) and OR = 1.82(1.23-2.70), respectively, relative to the normal weight group. Conclusion: BMI is associated with the invasiveness of PTC. There is a higher risk for ETE and TNM III/IV stage among patients with PTC in the overweight group and for ETE among patients with PTC in the obese group.

8.
Front Bioeng Biotechnol ; 8: 584807, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195148

RESUMO

Thermophilicity is a very important property of proteins, as it sometimes determines denaturation and cell death. Thus, methods for predicting thermophilic proteins and non-thermophilic proteins are of interest and can contribute to the design and engineering of proteins. In this article, we describe the use of feature dimension reduction technology and LIBSVM to identify thermophilic proteins. The highest accuracy obtained by cross-validation was 96.02% with 119 parameters. When using only 16 features, we obtained an accuracy of 93.33%. We discuss the importance of the different characteristics in identification and report a comparison of the performance of support vector machine to that of other methods.

9.
Jpn J Infect Dis ; 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33132301

RESUMO

Routine vaccination has proven to be highly effective in reducing the incidence of mumps. However, sporadic cases and/or mumps outbreaks do occur in children and adolescents younger than 15 years old, particularly among those 5-9 years old. To explore the characteristics of such outbreaks in Henan Province, clinical data of patients infected with MuV were collected, and the isolated MuV strains were phylogenetically analyzed. Of a total of 426 samples, MuV RNA targeting the small hydrophobic (SH) gene was detected in 153 samples. MuV-positive cases in each age group (< 5, 5-9,10-15, 16-19, and ≥ 20) accounted for 1%, 17%, 12%, 2% and 4% of the total number of cases, respectively. Phylogenetic analysis based on the SH gene sequences indicated that all of the isolated strains were of genotype F and isolates in the the same subcluster and identical SH gene sequences tended to be derived from the same community or municipalities when analyzed alongside epidemiological data. In conclusion, the incidence of mumps in Henan Province is high. The data provided in this study might promote further research in the clarification of specific cause of mumps outbreaks and which will facilitate the implementation of effective prevention and control measures.

10.
Biomed Res Int ; 2020: 3049302, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33145344

RESUMO

The present study was to investigate the effect of mesenteric lymph duct drainage on lung inflammatory response, histological alteration, and endothelial cell apoptosis in septic rats. Animals were randomly assigned into four groups: control, sham surgery, sepsis, and sepsis plus mesenteric lymph drainage. We used the colon ascendens stent peritonitis (CASP) procedure to induce the septic model in rats, and mesenteric lymph drainage was performed with a polyethylene (PE) catheter inserted into mesenteric lymphatic. The animals were sacrificed at the end of CASP in 6 h. The mRNA expression levels of inflammatory mediators were measured by qPCR, and the histologic damage were evaluated by the pathological score method. It was found that mesenteric lymph drainage significantly reduced the expression of TNF-α, IL-1ß, and IL-6 mRNA in the lung. Pulmonary interstitial edema and infiltration of inflammatory cells were alleviated by mesenteric lymph drainage. Moreover, increased mRNA levels of TNF-α, IL-1ß, IL-6 mRNA, and apoptotic rate were observed in PMVECs treated with septic lymph. These results indicate that mesenteric lymph duct drainage significantly attenuated lung inflammatory injury by decreasing the expression of pivotal inflammatory mediators and inhibiting endothelial apoptosis to preserve the pulmonary barrier function in septic rats.

11.
J Cardiovasc Pharmacol ; 76(5): 533-539, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33165134

RESUMO

Myocardial ischemia is a common reason that causes human death globally. Long noncoding RNA taurine upregulated 1 (TUG1) serves as an oncogene in a variety of cancers. In this article, we aimed to investigate the role of TUG1 and its underlying signal pathway in hypoxia-induced myocardial cell injury. Cell viability, apoptosis, and lactate dehydrogenase (LDH) release were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, flow cytometry, western blot assay, and LDH cytotoxicity assay. Quantitative real-time polymerase chain reaction was applied to measure the enrichment of TUG1 and miR-29a-3p. MiR-29a-3p was predicted as a target of TUG1 by StarBase bioinformatic software, and the target relationship between TUG1 and miR-29a-3p was verified by dual-luciferase reporter assay. Hypoxia treatment induced the apoptosis and LDH release while inhibited the viability of AC16 cells. TUG1 was markedly upregulated while the level of miR-29a-3p was notably decreased in hypoxia-stimulated AC16 cells. TUG1 contributed to hypoxia-induced AC16 injury. MiR-29a-3p depletion intensified hypoxia-induced AC16 damage. TUG1 negatively regulated the expression of miR-29a-3p through their direct interaction in AC16 cells. TUG1 silencing-mediated influences in hypoxia-induced AC16 cells were partly reversed by the interference of miR-29a-3p. In conclusion, TUG1 accelerated hypoxia-induced AC16 injury through inversely modulating the level of miR-29a-3p. TUG1/miR-29a-3p axis might be an underlying therapeutic target for myocardial ischemia.

13.
Food Chem ; 341(Pt 2): 128203, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33038803

RESUMO

Two different pearling degrees of wheat kernels (lightly-pearled: 14.4% and heavily-pearled: 38.9%) and un-pearled kernels were treated with ozone and evaluated for flour compositions and properties. Ozonation did not change main compositions and damaged starch content of three kernels' flours. Flour brightness of all three kernels was improved after ozone treatment. Ozonation enhanced the dough strength of the flours from un-pearled and pearled kernels and the effect elevated with increasing pearling degree. Ozone treatment increased the peak viscosity of flour and the level of increase in heavily-pearled kernels was greater than un-pearled and lightly-pearled. Ozonation resulted in an increase in the insoluble protein polymer content of heavily-pearled kernels' flour, but only had a slight effect on un-pearled lightly-pearled kernels. After ozone treatment, un-pearled and lightly-pearled kernels exhibited increases in molecular weight of starch, but heavily-pearled resulted in the opposite trend.

14.
Plant Physiol ; 184(4): 1731-1743, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33023939

RESUMO

During the course of evolution of land plants, different classes of flavonoids, including flavonols and anthocyanins, sequentially emerged, facilitating adaptation to the harsh terrestrial environment. Flavanone 3ß-hydroxylase (F3H), an enzyme functioning in flavonol and anthocyanin biosynthesis and a member of the 2-oxoglutarate-dependent dioxygenase (2-ODD) family, catalyzes the hydroxylation of (2S)-flavanones to dihydroflavonols, but its origin and evolution remain elusive. Here, we demonstrate that functional flavone synthase Is (FNS Is) are widely distributed in the primitive land plants liverworts and evolutionarily connected to seed plant F3Hs. We identified and characterized a set of 2-ODD enzymes from several liverwort species and plants in various evolutionary clades of the plant kingdom. The bifunctional enzyme FNS I/F2H emerged in liverworts, and FNS I/F3H evolved in Physcomitrium (Physcomitrella) patens and Selaginella moellendorffii, suggesting that they represent the functional transition forms between canonical FNS Is and F3Hs. The functional transition from FNS Is to F3Hs provides a molecular basis for the chemical evolution of flavones to flavonols and anthocyanins, which contributes to the acquisition of a broader spectrum of flavonoids in seed plants and facilitates their adaptation to the terrestrial ecosystem.

15.
Cells ; 9(10)2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33019500

RESUMO

All eukaryotes rely on the ubiquitin-proteasome system (UPS) and autophagy to control the abundance of key regulatory proteins and maintain a healthy intracellular environment. In the UPS, damaged or superfluous proteins are ubiquitinated and degraded in the proteasome, mediated by three types of ubiquitin enzymes: E1s (ubiquitin activating enzymes), E2s (ubiquitin conjugating enzymes), and E3s (ubiquitin protein ligases). Conversely, in autophagy, a vesicular autophagosome is formed that transfers damaged proteins and organelles to the vacuole, mediated by a series of ATGs (autophagy related genes). Despite the use of two completely different componential systems, the UPS and autophagy are closely interconnected and mutually regulated. During autophagy, ATG8 proteins, which are autophagosome markers, decorate the autophagosome membrane similarly to ubiquitination of damaged proteins. Ubiquitin is also involved in many selective autophagy processes and is thus a common factor of the UPS and autophagy. Additionally, the components of the UPS, such as the 26S proteasome, can be degraded via autophagy, and conversely, ATGs can be degraded by the UPS, indicating cross regulation between the two pathways. The UPS and autophagy cooperate and jointly regulate homeostasis of cellular components during plant development and stress response.

16.
Sci Rep ; 10(1): 15394, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958789

RESUMO

More than 150 ginsenosides have been isolated and identified from Panax plants. Ginsenosides with different glycosylation degrees have demonstrated different chemical properties and bioactivity. In this study, we systematically cloned and characterized 46 UGT94 family UDP-glycosyltransferases (UGT94s) from a mixed Panax ginseng/callus cDNA sample with high amino acid identity. These UGT94s were found to catalyze sugar chain elongation at C3-O-Glc and/or C20-O-Glc of protopanaxadiol (PPD)-type, C20-O-Glc or C6-O-Glc of protopanaxatriol (PPT)-type or both C3-O-Glc of PPD-type and C6-O-Glc of PPT-type or C20-O-Glc of PPD-type and PPT-type ginsenosides with different efficiencies. We also cloned 26 and 51 UGT94s from individual P. ginseng and P. notoginseng plants, respectively; our characterization results suggest that there is a group of UGT94s with high amino acid identity but diverse functions or catalyzing activities even within individual plants. These UGT94s were classified into three clades of the phylogenetic tree and consistent with their catalytic function. Based on these UGT94s, we elucidated the biosynthetic pathway of a group of ginsenosides. Our present results reveal a series of UGTs involved in second sugar chain elongation of saponins in Panax plants, and provide a scientific basis for understanding the diverse evolution mechanisms of UGT94s among plants.

17.
Neuron ; 108(4): 640-650.e4, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32910893

RESUMO

Animal feeding is controlled by external sensory cues and internal metabolic states. Does it also depend on enteric neurons that sense mechanical cues to signal fullness of the digestive tract? Here, we identify a group of piezo-expressing neurons innervating the Drosophila crop (the fly equivalent of the stomach) that monitor crop volume to avoid food overconsumption. These neurons reside in the pars intercerebralis (PI), a neuro-secretory center in the brain involved in homeostatic control, and express insulin-like peptides with well-established roles in regulating food intake and metabolism. Piezo knockdown in these neurons of wild-type flies phenocopies the food overconsumption phenotype of piezo-null mutant flies. Conversely, expression of either fly Piezo or mammalian Piezo1 in these neurons of piezo-null mutants suppresses the overconsumption phenotype. Importantly, Piezo+ neurons at the PI are activated directly by crop distension, thus conveying a rapid satiety signal along the "brain-gut axis" to control feeding.

18.
Ultrasound Med Biol ; 46(12): 3179-3187, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32907771

RESUMO

This meta-analysis was aimed at investigating the value of using contrast-enhanced ultrasound (CEUS) in the differential diagnosis of benign and malignant soft tissue masses (STMs). Relevant studies published before March 24, 2020 were identified through a comprehensive search of PubMed, Ovid, Cochrane and Web of Science. According to the inclusion criteria, five studies were selected comprising 746 patients. In the differential diagnosis of benign and malignant STMs, the pooled sensitivity and specificity of CEUS were 76% (95% confidence interval [CI]: 71%-81%; heterogeneity [I2] = 74.5%) and 67% (95% CI: 62%-71%; I2 = 36.5%), respectively. The diagnostic odds ratio was 7.37 (95% CI: 3.78%-14.35; I2 = 66.6%). The overall area under the curve was 0.77 (standard error: 0.0392). Subgroup analysis revealed that different index tests of CEUS resulted in different diagnostic performance. Importantly, CEUS is an effective method for the differential diagnosis between benign and malignant STMs.

19.
Artigo em Inglês | MEDLINE | ID: mdl-32754578

RESUMO

Rheumatoid arthritis (RA) is characterized by synovial hyperplasia and cartilage/bone destruction, which results in a high disability rate on human health and a huge burden on social economy. At present, traditional therapies based on drug therapy still cannot cure RA, in accompany with the potential serious side effects. Based on the development of nanobiotechnology and nanomedicine, energy conversion-based nanotherapy has demonstrated distinctive potential and performance in RA treatment. This strategy employs specific nanoparticles with intrinsic physiochemical properties to target lesions with the following activation by diverse external stimuli, such as light, ultrasound, microwave, and radiation. These nanoagents subsequently produce therapeutic effects or release therapeutic factors to promote necrotic apoptosis of RA inflammatory cells, reduce the concentration of related inflammatory factors, relieve the symptoms of RA, which are expected to ultimately improve the life quality of RA patients. This review highlights and discusses the versatile biomedical applications of energy conversion-based nanotherapy in efficient RA treatment, in together with the deep clarification of the facing challenges and further prospects on the final clinical translations of these energy conversion-based nanotherapies against RA.

20.
Appl Microbiol Biotechnol ; 104(18): 7927-7941, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32780289

RESUMO

Light-oxygen-voltage (LOV) proteins are ubiquitous photoreceptors that can interact with other regulatory proteins and then mediate their activities, which results in cellular adaptation and subsequent physiological changes. Upon blue-light irradiation, a conserved cysteine (Cys) residue in LOV covalently binds to flavin to form a flavin-Cys adduct, which triggers a subsequent cascade of signal transduction and reactions. We found a group of natural Cys-less LOV-like proteins in magnetotactic bacteria (MTB) and investigated its physiological functions by conducting research on one of these unusual LOV-like proteins, Amb2291, in Magnetospirillum magneticum. In-frame deletion of amb2291 or site-directive substitution of alanine-399 for Cys mutants impaired the protective responses against hydrogen peroxide, thereby causing stress and growth impairment. Consequently, gene expression and magnetosome formation were affected, which led to high sensitivity to oxidative damage and defective phototactic behaviour. The purified wild-type and A399C-mutated LOV-like proteins had similar LOV blue-light response spectra, but Amb2291A399C exhibited a faster reaction to blue light. We especially showed that LOV-like protein Amb2291 plays a role in magnetosome synthesis and resistance to oxidative stress of AMB-1 when this bacterium was exposed to red light and hydrogen peroxide. This finding expands our knowledge of the physiological function of this widely distributed group of photoreceptors and deepens our understanding of the photoresponse of MTB. KEY POINTS: • We found a group of Cys-less light-oxygen-voltage (LOV) photoreceptors in magnetotactic bacteria, which prompted us to study the light-response and biological roles of these proteins in these non-photosynthetic bacteria. • The Cys-less LOV-like protein participates in the light-regulated signalling pathway and improves resistance to oxidative damage and magnetic crystal biogenesis in Magnetospirillum magneticum. • This result will contribute to our understanding of the structural and functional diversity of the LOV-like photoreceptor and help us understand the complexity of light-regulated model organisms.

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