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1.
Med Ultrason ; 21(3): 349-352, 2019 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31476216

##### RESUMO

The long thoracic nerve (LTN) arises from the C5, C6 and C7 roots and innervates the serratus anterior muscle. Scapular winging is the landmark manifestation of LTN neuropathy and may develop after an accidental injury during selective cervical nerve root or inter-scalene brachial plexus blocks. Although its sonoanatomy has been described in the previous literature, how to gradually identify the entire nerve course has rarely been discussed. In this regard, the present paper aims to elaborate the scanning method of the LTN from its origin to its distal segment.

2.
Reg Anesth Pain Med ; 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31473664
3.
Artigo em Inglês | MEDLINE | ID: mdl-31476104

##### RESUMO

Charge-shift bonds (CSB) constitute a new class of bonds different than covalent/polar-covalent and ionic-bonds. Bonding in CSB is not contributed by either the covalent or the ionic structures of the bond, but rather by the resonance interaction between the structures. This essay describes the reasons why the CSB family was overlooked by valence-bond pioneers (Textbox 1). It then demonstrates that the unique status of CSBs is not theory-dependent. Thus, Valence-bond (VB), molecular-orbital (MO),[21,22] and Energy-Decomposition-Analysis (EDA)[23], as well as a variety of electron-density theories; Electron-Localization Function (ELF),[27] Quantum Thery of Atoms in Molecules (QTAIM),[24] and Electron-Stress Tensor (EST) approaches;[25,26] all these show the distinction of CSB vis-à-vis covalent and ionic bonds. Furthermore, the covalent-ionic resonance energy can be quantified from experiment, and hence having the same essential status as resonance energies of organic molecules, e.g., benzene. The essay then demonstrates how a variety of bond types -- dative-bonds, coordinative-bonds, and hypervalent-bonds, including 3-electron-bonds -- are CSBs. Subsequently, some experimental manifestations of CSBs are discussed, including recent experimental articulations of the concept.[78,81,82] The essay ends by arguing that the definition of CSB as a distinct family of bonding fulfills the necessary conditions for making such a claim. The distinction  between covalent-bonds and CSBs is thus fundamental, with a potential to bring about a Renaissance in the mental-map of the chemical bond, and to contribute to productive chemical diversity.

4.
Pregnancy Hypertens ; 17: 109-112, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31487625

##### RESUMO

Previous studies have suggested that altered miRNA expression in the placenta is associated with preeclampsia. The aim of this study was to investigate the expression of miR-424 in placental samples of severe preeclampsia (sPE) and uncomplicated pregnancy patients. miRNA was isolated from placentas obtained from 30 sPE patients and 30 healthy women. Quantitative real-time polymerase chain reaction was used to analyze the expression of miR-424. The prediction of target genes of miR-424 was performed using miRGen database. The function of these target genes was analyzed further by DAVID and Gorilla software. The expression of miR-424 was significantly lower in patients with sPE than in healthy controls. Changed expression of miR-424 in the case of pregnancy-related hypertensive disorders might affect the Wnt signaling pathway. These factors have a strong correlation with the development of PE. Expression of miR-424 in placenta was lower in patients with sPE, suggesting its role in the pathology of sPE.

5.
Nanotechnology ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31491784

##### RESUMO

Because of extreme three-dimensional field confinement and easy electrically tunability, plasmons in graphene nanostructures are promising candidates for plentiful applications, such as biosensing, photodetectors and modulators. However, up to now, graphene plasmons have been explored mostly on substrates. Substrates introduced scatterers, corrugations and dopants not only add damping but also obscure the intrinsic electronic properties of graphene. In this work, the near-field response of surface plasmons of suspended graphene circular resonators is studied with the scattering-type scanning near-field optical microscopy (s-SNOM) under different excitation wavelengths, $\lambda$ = 10.653 and 10.22 $\mu$m, respectively. Fundamental and higher order breathing plasmon modes are revealed in real-space with the Fermi energy of graphene of only 0.132 eV. Moreover, the direct experimental evidence on near-field electric tuning in suspended graphene resonators is demonstrated by using back-gate tuning. Our work not only provides a foundation to truly understand the properties of electrons inside pure graphene, but shines light on the applications in optoelectronic devices with suspended two-dimensional materials.

6.
Can J Diabetes ; 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31492620

##### RESUMO

OBJECTIVE: The aim of this study was to determine whether perinatal outcomes differ between Caucasian and Asian subgroups of women with gestational diabetes mellitus (GDM) through use of standard vs ethnicity-specific birthweight curves. METHODS: This retrospective cohort study included 537 women with GDM, within the ethnically diverse province of Ontario, Canada. Study outcomes included large-for-gestational-age (LGA) and small-for-gestational-age (SGA) birthweights in newborns of women from prevalent Asian ethnic groups compared with newborns of Caucasian women. Odds ratios were adjusted for maternal age, parity, prepregnancy body mass index, gestational weight gain and insulin use in pregnancy. RESULTS: Of the 537 women participing in the study, 228 (35.8%) were Caucasian, 109 (17.1%) South Asian, 141 (22.1%) East Asian and 59 (9.3%) Filipino. Using standard birthweight curves, compared with Caucasian women, the risk of LGA was lower among South Asian (adjusted odds ratio [aOR], 0.065; 95% confidence interval [CI], 0.01 to 0.49) and East Asian (aOR, 0.36; 95% CI, 0.14 to 0.95) women. The aOR for SGA was notably higher among South Asian women (aOR, 2.96; 95% CI, 1.24 to 7.09). Significant effects were not seen among Filipino women. Use of ethnicity-specific birthweight curves largely attenuated these associations, except for LGA in South Asian mothers (aOR, 0.27; 95% CI, 0.09 to 0.81). CONCLUSION: South Asian women with GDM are at lower risk of having an LGA newborn, even after accounting for maternal risk factors or the use of an ethnicity-specific birthweight curve.

7.
Anal Cell Pathol (Amst) ; 2019: 1598182, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482051

##### RESUMO

Human hepatocellular carcinoma (HCC) is the most common and recurrent type of primary adult liver cancer without any effective therapy. Plant-derived compounds acting as anticancer agents can induce apoptosis by targeting several signaling pathways. Strigolactone (SL) is a novel class of phytohormone, whose analogues have been reported to possess anticancer properties on a panel of human cancer cell lines through inducing cell cycle arrest, destabilizing microtubular integrity, reducing damaged in the DNA repair machinery, and inducing apoptosis. In our previous study, we reported that a novel SL analogue, TIT3, reduces HepG2 cell proliferation, inhibits cell migration, and induces apoptosis. To decipher the mechanisms of TIT3-induced anticancer activity in HepG2, we performed RNA sequencing and the differential expression of genes was analyzed using different tools. RNA-Seq data showed that the genes responsible for microtubule organization such as TUBB, BUB1B, TUBG2, TUBGCP6, TPX2, and MAP7 were significantly downregulated. Several epigenetic modulators such as UHRF1, HDAC7, and DNMT1 were also considerably downregulated, and this effect was associated with significant upregulation of various proapoptotic genes including CASP3, TNF-α, CASP7, and CDKN1A (p21). Likewise, damaged DNA repair genes such as RAD51, RAD52, and DDB2 were also significantly downregulated. This study indicates that TIT3-induced antiproliferative and proapoptotic activities on HCC cells could involve several signaling pathways. Our results suggest that TIT3 might be a promising drug to treat HCC.

8.
Soft Matter ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31490517

##### RESUMO

9.
An Acad Bras Cienc ; 91(3): e20190068, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31508664

##### RESUMO

To investigate the mechanism of different exercise patterns on neurological function after focal cerebral ischaemia in rats. Rats with focal cerebral cerebral ischaemia were randomly divided into an aerobic exercise group, an exhaustive exercise group and a control group, with 8 rats in each group. A score for nerve function in each group was calculated, and the ultrastructure of nerve cells was observed. Levels of NO and NOS in the brain motor area of the âârats were measured in each group. The aerobic exercise group had lower nerve function scores than the exhaustive exercise group and higher scores than the control group (P<0.05). Under transmission electron microscopy, irregular shapes and organs were observed in nerve cells in the control group, while regular cell shapes and organs were observed in the aerobic exercise group. The aerobic exercise group and exhaustive exercise group had higher measures of NO content, NOS activity and eNOS, nNOS and iNOS gene expression than the control group, but eNOS expression in the aerobic exercise group and iNOS expression in the exhaustive exercise group were clearly higher according to RT-PCR (P<0.05). Aerobic exercise can promote the expression of NOS, mainly in eNOS, which can promote nerve repair.

10.
Math Biosci Eng ; 16(5): 4846-4872, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31499693

##### RESUMO

Radiofrequency ablation (RFA) and microwave ablation (MWA) have become an important means for treating liver tumors. RFA and MWA are a minimally invasive therapy which involves an ablation applicator or needle (i.e., radiofrequency electrode or microwave antenna) inserted percutaneously into a tumor under the guidance of medical imaging, so as to destroy the tumor in situ by heating-induced coagulation necrosis. Treatment planning, particularly needle trajectory planning, is crucial to RFA and MWA. In clinical procedures, however, needle trajectory planning still relies on the personal experience of clinicians. Manual needle trajectory planning is tedious and may cause inter-operator difference. Therefore, computer-assisted needle trajectory planning techniques are of clinical value and have been extensively explored. However, a literature review that focuses on computer-assisted needle trajectory planning for liver tumor RFA and MWA has not been reported. In this paper, we conducted an extensive review on computer-assisted needle trajectory planning for RFA and MWA of liver tumors. Fundamentals of needle trajectory planning are summarized. Algorithms for single-needle and multi-needle trajectory planning are analyzed. Shortcomings of current computer-assisted needle trajectory planning algorithms are discussed and future developments are suggested.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31502223

##### RESUMO

This study reports a rapid and robust method for the differentiation of Asian and American ginseng samples based on differential ion mobility spectrometry-tandem mass spectrometry (DMS-MS/MS). Groups of bioactive ginsenoside/pseudo-ginsenoside isomers, including Rf/Rg1/F11, Rb2/Rb3/Rc, and Rd/Re, in the ginseng extracts were sequentially separated using DMS with stepwise changes in the gas modifier concentration prior to MS analysis. The identities of the spatially separated ginsenoside/pseudo-ginsenoside isomers were confirmed by their characteristic compensation voltages at specific modifier loading and MS/MS product ions. As expected, Asian ginseng samples contained some Rf and an insignificant amount of F11, whereas American ginseng samples had a high level of F11 but no Rf. The origin of the whole and sliced ginseng could further be confirmed using the quantitative ratios of three sets of ginsenoside markers, namely, Rg1/Re, Rb1/Rg1, and Rb2/Rc. Based on our results, new benchmark ratios of Rg1/Re < 0.15, Rb1/Rg1 > 2.15, and Rb2/Rc < 0.26 were proposed for American ginseng (as opposed to Asian ginseng).

12.
J Environ Sci (China) ; 85: 156-167, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471022

##### RESUMO

This study evaluated uranium sequestration performance in iron-rich (30â¯g/kg) sediment via bioreduction followed by reoxidation. Field tests (1383 days) at Oak Ridge, Tennessee demonstrated that uranium contents in sediments increased after bioreduced sediments were re-exposed to nitrate and oxygen in contaminated groundwater. Bioreduction of contaminated sediments (1200â¯mg/kg U) with ethanol in microcosm reduced aqueous U from 0.37 to 0.023â¯mg/L. Aliquots of the bioreduced sediment were reoxidized with O2, H2O2, and NaNO3, respectively, over 285 days, resulting in aqueous U of 0.024, 1.58 and 14.4â¯mg/L at pH 6.30, 6.63 and 7.62, respectively. The source- and the three reoxidized sediments showed different desorption and adsorption behaviors of U, but all fit a Freundlich model. The adsorption capacities increased sharply at pH 4.5 to 5.5, plateaued at pH 5.5 to 7.0, then decreased sharply as pH increased from 7.0 to 8.0. The O2-reoxidized sediment retained a lower desorption efficiency at pH over 6.0. The NO3--reoxidized sediment exhibited higher adsorption capacity at pH 5.5 to 6.0. The pH-dependent adsorption onto Fe(III) oxides and formation of U coated particles and precipitates resulted in U sequestration, and bioreduction followed by reoxidation can enhance the U sequestration in sediment.

##### Assuntos
Biodegradação Ambiental , Poluentes Radioativos do Solo/metabolismo , Urânio/metabolismo , Sedimentos Geológicos/química , Poluentes Radioativos do Solo/química , Tennessee , Urânio/química
13.
Cell Stem Cell ; 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31474560

##### RESUMO

Structural and transcriptional changes during early brain maturation follow fixed developmental programs defined by genetics. However, whether this is true for functional network activity remains unknown, primarily due to experimental inaccessibility of the initial stages of the living human brain. Here, we developed human cortical organoids that dynamically change cellular populations during maturation and exhibited consistent increases in electrical activity over the span of several months. The spontaneous network formation displayed periodic and regular oscillatory events that were dependent on glutamatergic and GABAergic signaling. The oscillatory activity transitioned to more spatiotemporally irregular patterns, and synchronous network events resembled features similar to those observed in preterm human electroencephalography. These results show that the development of structured network activity in a human neocortex model may follow stable genetic programming. Our approach provides opportunities for investigating and manipulating the role of network activity in the developing human cortex.

14.
PLoS One ; 14(9): e0222091, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31509561

##### RESUMO

Quantitative analysis of the contribution rate of China's hydraulic science and technology and analysis of the underlying reasons behind changes provide an important foundation upon which the government can formulate water policies. This paper abandons the assumption of a scale economy and separates the changes of benefits brought about by the scale from scientific and technological progress, thus changing the C-D production function from linear to nonlinear. Based on a feedforward neural network, it calculates the coefficient of the output elasticity, the economic contribution rate of China's hydraulic science and technology and the scale economies for each year using relevant data from 1981 to 2016. The results show that (1) the average contribution rate of capital investment from 1981 to 2016 was 47.3%, and the average contribution rate of labor from 1981 to 2016 was 9.1%. It is not obvious that the significant increase in the labor force has contributed to the growth of China's water conservancy industry. (2) The average contribution rate of scale economies in 1981-2016 was 26.7%, and the contribution rate of scale economies is negatively correlated with the capital contribution rate. (3) The average contribution rate of China's hydraulic science and technology was 43.6% from 1981 to 2016, and the average contribution rate of the total factor productivity after removing scale economies from 1981 to 2016 was 16.9%. During the period of the 6th Five-Year Plan(1981~1985), the contribution rate of water conservancy science and technology was relatively high. Since that time, it has remained at 40%. In recent years, as water conservancy reforms in key areas have made positive progress, scientific and technological progress has increased the growth of water conservancy benefits annually.

15.
Dev Comp Immunol ; 102: 103489, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31473266

##### RESUMO

The Canine Distemper Virus (CDV) is a high fatal virus to the giant panda (Ailuropoda melanoleuca), where CDV vaccination is a key preventative measure in captive giant pandas. However, the immune response of giant pandas to CDV vaccination has been little studied. In this study, we investigated the blood transcriptome expression profiles of five giant panda cubs after three inoculations, 21 days apart. Blood samples were collected before vaccination (0 Day), and 24â¯h after each of the three inoculations; defined here as 1 Day, 21 â¯Day, and 42 â¯Day. Compared to 0 Day, we obtained 1262 differentially expressed genes (DEGs) during inoculations. GO and KEGG pathways enrichment analysis of these DEGs found 222 GO terms and 40 pathways. The maximum immune-related terms were enriched by DEGs from comparisons of 21 â¯Day and 0 Day. In the PPI analysis, we identified RSAD2, IL18, ISG15 immune-related hub genes from 1 Day and 21 Day comparison. Compared to 0 Day, innate immune-related genes, TLR4 and TLR8, were up-regulated at 1 Day, and the expressions of IRF1, RSAD2, MX1, and OAS2 were highest at 21 â¯Day. Of the adaptive immune-related genes, IL15, promoting T cell differentiation into CD8+T cells, was up-regulated after the first two inoculations, IL12ß, promoting T cell differentiation into memory cells, and IL10, promoting B cell proliferation and differentiation, were down-regulated during three inoculations. Our results indicated that the immune response of five giant panda cubs was strongest after the second inoculation, most likely protected against CDV infection through innate immunity and T cells, but did not produce enough memory cells to maintain long-term immunity after CDV vaccination.

16.
Oncogene ; 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399647

##### RESUMO

ZNF322A is an oncogenic zinc-finger transcription factor. Our published results show that ZNF322A positively regulates transcription of alpha-adducin (ADD1) and cyclin D1 (CCND1) to promote tumorgenicity of lung cancer. However, the upstream regulatory mechanisms of ZNF322A protein function remain elusive. Here, we demonstrate that AKT could phosphorylate ZNF322A by in vitro kinase assay and cell-based mass spectrometry analysis. Overexpression of AKT promoted ZNF322A protein stability and transcriptional activity, whereas these effects were inhibited by knockdown of AKT or treating with AKT inhibitor. We studied AKT-mediated phosphorylation sites, viz. Thr-150, Ser-224, Thr-234, and Thr-262. ZNF322A phosphorylation at Thr-262 by AKT promoted ZNF322A protein stability thus increased ADD1 promoter activity. Interestingly, phosphorylation at Thr-150, Ser-224, and Thr-234 enhanced transcription activity without affecting protein stability of ZNF322A. Chromatin immunoprecipitation and DNA affinity precipitation assays showed that ZNF322A phosphorylation defective mutants Thr-150A, Ser-224A, and Thr-234A attenuated chromatin binding and DNA binding affinity to ADD1 and CCND1 promoters compared with wild-type ZNF322A. Furthermore, AKT-mediated Thr-150, Ser-224, Thr-234, and Thr-262 phosphorylation promoted lung cancer cell growth and metastasis in vitro and in vivo. Clinically, expression of phosphorylated ZNF322A (p-ZNF) correlated with actively phosphorylated AKT (p-AKT) in tumor specimens from 150 lung cancer patients. Multivariate Cox regression analysis indicated that combined p-AKT and p-ZNF expression profile was an independent factor to predict the clinical outcome in lung cancer patients. Our results reveal a new mechanism of AKT signaling in promoting ZNF322A protein stability and transcriptional activity in lung cancer cell, xenograft, and clinical models.

17.
J Invest Surg ; : 1-6, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31366250

##### RESUMO

Background: Few comparative studies have focused on the advantages and disadvantages of transthoracic device closure, transcatheter device closure, and surgical repair via right submammary thoracotomy for restrictive ventricular septal defect (VSD). In this article, we compared the safety, efficacy, and clinical effects of these three treatments. Methods: The clinical data of 192 pediatric patients with a restrictive VSD in our hospital from January 2017 to May 2018 were retrospectively collected and analyzed. According to the different treatments, the patients were divided into three groups (the surgical and device groups). Results: There was no significant difference in the demographic characteristics, VSD size, mean pulmonary artery pressure, or cardiothoracic ratio. In addition, there were significant differences in the duration of mechanical ventilation, operation, hospitalization, and ICU stay between the two device groups and the surgical group, but there were no significant differences between the two device groups. Conclusions: Transthoracic device closure, transcatheter device closure, and surgical repair via right submammary thoracotomy for restrictive VSD repair are all safe and feasible. These three treatments have their own disadvantages and advantages and should be selected according to individual patients.

18.
PLoS One ; 14(8): e0221040, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31437239

##### RESUMO

Angelica dahurica is a widely grown plant species with multiple uses, especially in the medical field. However, the frequent introduction of A. dahurica to new areas has made it difficult to distinguish between varieties. Simple sequence repeats (SSRs) detected based on transcriptome analyses are very useful for constructing genetic maps and analyzing genetic diversity. They are also relevant for the molecular marker-assisted breeding of A. dahurica. We identified 33,724 genic SSR loci based on transcriptome sequencing data. A total of 114 primer pairs were designed for the SSR loci and were tested for their specificity and diversity. Ten SSR loci in untranslated regions were ultimately selected. Subsequently, 56 A. dahurica ecotypes collected from different regions were analyzed. The SSR loci comprised 2-8 alleles, with a mean of 5.2 alleles per locus. The polymorphic information content value and Shannon's information index were 0.6274-0.2702 (average of 0.4091) and 1.3040-0.5618 (average of 0.8475), respectively. Thus, the 10 novel SSRs identified in this study were almost in accordance with Harvey-Weinberg equilibrium and will be useful for analyzing A. dahurica genetic relationships. The results of this study confirm the potential value of transcriptome databases for the development of new SSR markers.

19.
ACS Chem Neurosci ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31441641

##### RESUMO

Here, we present a series of dual-target phosphodiesterase 9 (PDE9) and histone deacetylase (HDAC) inhibitors devised as pharmacological tool compounds for assessing the implications of these two targets in Alzheimer's disease (AD). These novel inhibitors were designed taking into account the key pharmacophoric features of known selective PDE9 inhibitors as well as privileged chemical structures, bearing zinc binding groups (hydroxamic acids and ortho-amino anilides) that hit HDAC targets. These substituents were selected according to rational criteria and previous knowledge from our group to explore diverse HDAC selectivity profiles (pan-HDAC, HDAC6 selective, and class I selective) that were confirmed in biochemical screens. Their functional response in inducing acetylation of histone and tubulin and phosphorylation of cAMP response element binding (CREB) was measured as a requisite for further progression into complete in vitro absorption, distribution, metabolism and excretion (ADME) and in vivo brain penetration profiling. Compound 31b, a selective HDAC6 inhibitor with acceptable brain permeability, was chosen for assessing in vivo efficacy of these first-in-class inhibitors, as well as studying their mode of action (MoA).

20.
Arch Microbiol ; 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31463601

##### RESUMO

To evaluate the changes in bacterial diversity at various time points under resveratrol supplementation, we aimed to investigate the diversification of gut microbiota and the changes in total genetic diversity. We performed 16S rDNA gene sequencing at different time points (15, 30, and 45 days) to analyze the gut microbiota of tilapia. Fusobacteria, Proteobacteria, and Bacteroidetes (15 days) or Cyanobacteria (30 and 45 days) were found to be the three most abundant phyla. Cyanobacteria (15 and 30 days), Proteobacteria (15 days), Firmicutes and Chlamydiae (30 and 45 days), Planctomycetes (30 days), Bacteroidetes, Actinobacteria, and Fusobacteria (45 days) in the 0.05 g/kg RES group increased as compared to that in the controls. Proteobacteria and Cyanobacteria significantly decreased and increased at 30 and 45 days, respectively, while the reverse pattern was observed at 15 days. The Bacteroidetes:Firmicutes and Proteobacteria:Cyanobacteria ratios were significantly increased (15 and 45 days, P < 0.05) and decreased (30 days, P < 0.05). RES supplementation did not affect the richness and diversity of the gut microbiota in tilapia. Our findings may contribute to the development of strategies for the management of diseases.