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1.
J Nanosci Nanotechnol ; 20(2): 900-908, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383085

RESUMO

A series of polyurethane hydrogel and polyurethane thermoplastic elastomer composite based separation membranes were successfully prepared via wet phase inversion method. The morphology, chemical structure, phase transition temperature and crystallinity of the polyurethane (PU) membranes were characterized by SEM, FTIR, DSC, and XRD, respectively. The SEM observation showed that the PU membranes exhibited irregular porous structure on the surface and path of the hole was flexural and asymmetrical in cross-section. The FTIR analysis demonstrated that thermalsensitive groups and pH-sensitive components (-N(CH3)-) were incorporated into the PU network. The DSC experiment and XRD experiment showed that the regular arrangement of PU network was destroyed partly due to the introduction of polyurethane thermoplastic elastomer. The equilibrium swelling ratio (ESR) and water flux (J) for PU membranes clearly decreased and increased with functional groups and sophisticated structure of PU membranes, respectively. In addition, the permeation experiments indicated that the permeation percentage (P) of the glycine was strongly affected by the external temperature and pH value.

2.
World J Gastroenterol ; 25(31): 4502-4511, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31496628

RESUMO

BACKGROUND: As one effective treatment for lateral pelvic lymph node (LPLN) metastasis (LPNM), laparoscopic LPLN dissection (LPND) is limited due to the complicated anatomy of the pelvic sidewall and various complications after surgery. With regard to improving the accuracy and completeness of LPND as well as safety, we tried an innovative method using indocyanine green (ICG) visualized with a near-infrared (NIR) camera system to guide the detection of LPLNs in patients with middle-low rectal cancer. AIM: To investigate whether ICG-enhanced NIR fluorescence-guided imaging is a better technique for LPND in patients with rectal cancer. METHODS: A total of 42 middle-low rectal cancer patients with clinical LPNM who underwent total mesorectal excision (TME) and LPND between October 2017 and March 2019 at our institution were assessed and divided into an ICG group and a non-ICG group. Clinical characteristics, operative outcomes, pathological outcomes, and postoperative complication information were compared and analysed between the two groups. RESULTS: Compared to the non-ICG group, the ICG group had significantly lower intraoperative blood loss (55.8 ± 37.5 mL vs 108.0 ± 52.7 mL, P = 0.003) and a significantly larger number of LPLNs harvested (11.5 ± 5.9 vs 7.1 ± 4.8, P = 0.017). The LPLNs of two patients in the non-IVG group were residual during LPND. In addition, no significant difference was found in terms of LPND, LPNM, operative time, conversion to laparotomy, preoperative complication, or hospital stay (P > 0.05). CONCLUSION: ICG-enhanced NIR fluorescence-guided imaging could be a feasible and convenient technique to guide LPND because it could bring specific advantages regarding the accuracy and completeness of surgery as well as safety.

3.
Org Lett ; 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31512879

RESUMO

An efficient synthesis of privileged allylic amines has been developed via cobalt-catalyzed allylation of amides with styrenes, in which DMSO was used as both the solvent and the α-methylene source. This transformation features high yields, and selectivity for the (E)-isomer of the linear product. Through the experimental and computational investigations, a sequential K2S2O8-mediated oxidative coupling/cobalt-assisted regioselective alkene insertion/ß-H elimination/alkene dissociation/hydride transfer process has also been deduced.

4.
Nat Commun ; 10(1): 3992, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488849

RESUMO

Most current evidence indicates that DNA polymerases ε and δ, respectively, perform the bulk of leading and lagging strand replication of the eukaryotic nuclear genome. Given that ribonucleotide and mismatch incorporation rates by these replicases influence somatic and germline patterns of variation, it is important to understand the details and exceptions to this overall division of labor. Using an improved method to map where these replicases incorporate ribonucleotides during replication, here we present evidence that DNA polymerase δ universally participates in initiating leading strand synthesis and that nascent leading strand synthesis switches from Pol ε to Pol δ during replication termination. Ribonucleotide maps from both the budding and fission yeast reveal conservation of these processes. These observations of replisome dynamics provide important insight into the mechanisms of eukaryotic replication and genome maintenance.

5.
Math Biosci Eng ; 16(5): 4923-4935, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31499697

RESUMO

Computer graphic images (CGI) can be manufactured very similar to natural images (NI) by state-of-the-art algorithms in computer graphic filed. Thus, there are various identification algorithms proposed to detect CGI. However, the manipulation is complicated and difficult for an ultimate CGI against the forensic algorithms. Further, the forensics on CGI and NI made achievements in the different aspects with the encouragement of deep learning. Though the generated CGI can achieve high quality automatically by generative adversarial networks (GAN), CGI generation based on GAN is difficult to ensure that it cannot be detected by forensics. In this paper, we propose a brief and effective architecture based on GAN for preventing the generated images being detected under the forensics on CGI and NI. The adapted characteristics will make the CGI generated by GAN fools the detector and keep the end-to-end generation mode of GAN.

6.
Mol Cell ; 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31495565

RESUMO

Break-induced replication (BIR) is a pathway of homology-directed repair that repairs one-ended DNA breaks, such as those formed at broken replication forks or uncapped telomeres. In contrast to conventional S phase DNA synthesis, BIR proceeds by a migrating D-loop and results in conservative synthesis of the nascent strands. DNA polymerase delta (Pol δ) initiates BIR; however, it is not known whether synthesis of the invading strand switches to a different polymerase or how the complementary strand is synthesized. By using alleles of the replicative DNA polymerases that are permissive for ribonucleotide incorporation, thus generating a signature of their action in the genome that can be identified by hydrolytic end sequencing, we show that Pol δ replicates both the invading and the complementary strand during BIR. In support of this conclusion, we show that depletion of Pol δ from cells reduces BIR, whereas depletion of Pol ε has no effect.

7.
Org Lett ; 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31448622

RESUMO

A double catalytic system combining 2-mercaptobenzoic acid and a chiral phase transfer substance was disclosed for the intermolecular cross Rauhut-Currier reaction of 2-cyclopentenone and isatin-based alkylidene malononitriles. The resulting chiral adducts were sequentially assembled with diverse electron-deficient olefins to furnish highly enantioenriched cyclohexane derivatives (up to 96:4 er, >19:1 dr). A similar catalytic system of 2-mercaptobenzoic acid and quinine was further developed for the reaction of 2-cyclopentenone and α-cyano chalcones (up to 96.5:3.5 er).

8.
Talanta ; 205: 120117, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450427

RESUMO

Carbon quantum dots (CQDs), owing to its unique optical properties, have achieved tremendous progress for the detection of different metal ions, organic small molecules, macromolecules, etc. Here we synthesized fluorescent CQDs by a simple one-step microwave-assisted method using 3,4-Dihydroxy-l-phenylalanine (levodopa) as the carbon resource. The CQDs proved to be a multifunctional probe which can be used for detection of various species including copper ion, biothiols and curcumin, via different mechanisms. The selective detection of copper ion was obtained by fluorescence quenching and the mechanism was proved to be static quenching by electrostatic interaction. The fluorescence of levoCQDs-Cu2+ system can be recovered by biothiols (GSH, Cys and Hcy), implying levoCQDs-Cu2+ system can also be applied for biothiols detection. The excitation spectrum of levoCQDs had a good overlap with the absorption peak of curcumin, making it as a suitable curcumin probe by fluorescence quenching via inner filter effect (IFE). Furthermore, the levoCQDs can also track the formation of Cu2+-Curcumin complexes by restoring the fluorescence of the CQDs in levoCQDs and Cu2+-Curcumin system, and this feature may be exploited in the mechanism study of Cu2+-Curcumin in the treatment of Alzheimer's disease. The fluorescent levoCQDs were finally used for Cu2+ and curcumin detection in some real samples including different types of environmental water samples and human serum samples, providing a convenient strategy to monitor Cu2+and curcumin in environmental and biological samples.

9.
Sensors (Basel) ; 19(16)2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31426315

RESUMO

Fiber-reinforced polymer (FRP) composites have been widely employed to design advanced structural columns such as the hybrid FRP-concrete-steel double-skin tubular column (hybrid DSTC) with potential benefits. To date, the safety and self-monitoring of the hybrid DSTCs are still a challenge to overcome due to the complex damage scenarios. This paper investigates the self-sensing performance of a newly developed smart double-skin tubular confined concrete column (smart BFST-DSTC) made of basalt FRP-steel composite with built-in optical fiber Bragg grating sensors (OFBGs). The design of the smart BFST-DSTC and sensing principle are firstly addressed, followed by an experimental investigation on the basic mechanical properties and strain-based sensing performance of ten scaled specimens under axial compression. The outcomes reveal the enhancement of the proposed column in terms of load-carrying capacity, confinement ratio, and axial stress-axial strain behavior, as well as failure and damage modes when compared with the hybrid DSTC. The self-sensing investigation demonstrates that the measurement range satisfies the requirement to monitor and evaluate the hoop strains of the FRP jackets and the health state of the inner tube. The smart BFST-DSTC can replace the hybrid DSTC with the ability to provide early failure warning and life cycle health monitoring.

10.
Fish Physiol Biochem ; 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31428893

RESUMO

Fish growth can be modulated dynamically through the brain-pituitary-liver regulation axis. In the present study, whole transcriptomes of the pituitary and liver from Golden Pompano Trachinotus blochii were sequenced in seawater at 20 °C (T_low) and 25 °C (T_high). A total of 187,277,583 paired-end reads were assembled to obtain 100,495 transcripts, corresponding to 83,974 genes. These reads were mapped to T. blochii transcripts, and the mapping accuracy ranged from 80.4 to 94.9%. Two lists of differentially expressed genes were obtained by comparisons of pituitary and liver T_low versus T_high groups, comprising 458 and 205 genes, respectively. Of these, 33 differentially expressed genes were common between the two lists. Twelve GO terms were overrepresented for the 458 differentially expressed genes in the pituitary, and it is noteworthy that the GO term galanin receptor activity (GO: 0004966) related to the modulation of appetite and metabolism, whose genes made up half of all assembled genes in the term. For the 205 differentially expressed genes in the liver, 19 overrepresented GO terms were mainly related to immune regulation, digestion, and protein metabolism. Among the common differentially expressed genes, there were 32 genes that had identical changing trends in both pituitary and liver comparisons. Furthermore, two GO terms inorganic diphosphatase activity and MHC protein complex were overrepresented. These results indicate that the brain could regulate pituitary function through galanin signal mechanism and that the metabolism of liver was further optimized to modulate immunity and growth under different temperatures.

11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(4): 1227-1231, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418384

RESUMO

OBJECTIVE: To investigate the genetic carrier rate of thalassemia and its gene mutation types as well as the distribution characteristics among the people in Lingshui Li autonomous county of Hainan province, so as to provide the basis for making the prevention programs of thalassemia in administrative departments. METHODS: Samples were collected from couples undergoing premarital and pregestational screenings, in which the positive ones in preliminary screening were further tested by genetic diagnoses and the genotypes were analyzed. RESULTS: The rate of thalassemia gene carriers was 19.41% (274/1412) of the couples of childbearing age in Lingshui Li autonomous County of Hainan Province. In these carriers,α-thalassemia accounted for 83.21%(228/274), ß-thalassemia for 8.03%(22/274), and both α-and ß-thalassemia gene accounted for 8.76% (28/274). CONCLUSION: The carrying rate of thalassemia gene in population Lingshui Li autonomous county of Hainan province is high, and its distribution has geographical characteristics,the major type is α-thalassemia. Blood screening and genetic diagnosis of thalassemia should be strengthened, and corresponding measures should be taken to reduce its gene frequency.


Assuntos
Talassemia alfa , Talassemia beta , China , Testes Genéticos , Genótipo , Heterozigoto , Humanos
12.
Nat Commun ; 10(1): 3474, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375678

RESUMO

Neuron morphology is recognized as a key determinant of cell type, yet the quantitative profiling of a mammalian neuron's complete three-dimensional (3-D) morphology remains arduous when the neuron has complex arborization and long projection. Whole-brain reconstruction of neuron morphology is even more challenging as it involves processing tens of teravoxels of imaging data. Validating such reconstructions is extremely laborious. We develop TeraVR, an open-source virtual reality annotation system, to address these challenges. TeraVR integrates immersive and collaborative 3-D visualization, interaction, and hierarchical streaming of teravoxel-scale images. Using TeraVR, we have produced precise 3-D full morphology of long-projecting neurons in whole mouse brains and developed a collaborative workflow for highly accurate neuronal reconstruction.

13.
Sci Rep ; 9(1): 11468, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391542

RESUMO

Lumbosacral nerve root avulsion leads to widespread death of neurons in the anterior horn area of the injured spinal cord, which results in dysfunction in the lower extremities. Heat shock protein 27 (Hsp27) has been found to play cytoprotective roles under adverse conditions. However, the role of Hsp27 in neurons after lumbosacral nerve root avulsion is unknown. The aim of the present study was to investigate the effects and mechanism of action of Hsp27 on neurons after lumbosacral nerve root avulsion. It was found that Hsp27 expression was elevated in the anterior horn area of the injured spinal cord and the up-regulation of Hsp27 protected neurons against apoptosis after lumbosacral nerve root avulsion. In addition, Hsp27 plays an anti-apoptotic role by suppressing oxidative stress reactions. These findings indicated that Hsp27 may play a key role in resistance to lumbosacral nerve root avulsion-induced neuron apoptosis and may prove to be a potential strategy for improving prognosis after lumbosacral nerve root avulsion.

14.
Cells ; 8(8)2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31426448

RESUMO

: Accumulative evidence indicated that the pathologically accumulated metal ions (iron species and Mn3+) and abnormally up-regulated monoamine oxidase B (MAOB) activity induced oxidation of endogenous dopamine (DA) can lead to mitochondria impairment, lysosome dysfunction, proteasome inhibition, and selective DA neuron vulnerability, which is implicated in the pathogenesis of Parkinson's disease (PD). The DA oxidation can generate deleterious reactive oxygen species (ROS) and highly reactive DA quinones (DAQ) to induce DA-related toxicity, which can be alleviated by DA oxidation suppressors, ROS scavengers, DAQ quenchers, and MAOB inhibitors. On the other hand, the nuclear factor erythroid 2-related factor 2 (Nrf2)-Keap1 and Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) anti-oxidative and proliferative signaling pathways play roles in anti-oxidative cell defense and mitochondria biogenesis, which is implicated in DA neuron protections. Therefore, agents with capabilities to suppress DA-related toxicity including inhibition of DA oxidation, scavenge of ROS, detoxification of DAQ, inhibition of MAOB, and modulations of anti-oxidative signaling pathways can be protective to DA neurons. Accumulative evidence shows that tea or coffee consumptions and smoking are related to deceased PD prevalence with unknown mechanisms. In this study, we investigate the protective capabilities of tea polyphenols and other PD relevant agents to inhibit DA-related toxicity and protect against environmental or genetic factors induced DA neuron degeneration in vitro and in vivo. We find that tea polyphenols can significantly suppress DA-related toxicity to protect DA neurons. The tea polyphenols can protect DA neurons via inhibition of DA oxidation, conjugation with DAQ, scavenge of ROS, inhibition of MAOB, and modulations of Nrf2-Keap1 and PGC-1α anti-oxidative signaling pathways. The tea polyphenols with more phenolic hydroxyl groups and ring structures have stronger protective functions. The protective capabilities of tea polyphenols is further strengthened by evidence that phenolic hydroxyl groups can directly conjugate with DAQ. However, GSH and other sulfhydyl groups containing agents have weaker capabilities to abrogate DA oxidation, detoxify ROS and DAQ and inhibit MAOB; whereas nicotine (NICO) and caffeine (CAF) can only modulate Nrf2-Keap1 and PGC-1α pathways to protect DA neurons weakly. The tea polyphenols are identified to protect against overexpression of mutant A30P α-synuclein (α-syn) induced DA neuron degeneration and PD-like symptoms in transgenic Drosophila. Based on achievements from current studies, the excellent and versatile protective capabilities of tea polyphenols are highlighted, which will contribute and benefit to future anti-PD therapy.

15.
Eur J Surg Oncol ; 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31362841

RESUMO

OBJECTIVE: To investigate the factors related to positive surgical margins of gastric cancer and their correlation with the prognosis of these patients. METHODS: The clinicopathological data of gastric cancer patients undergoing gastrectomy were collected, and the relationship between surgical margins status and patient outcome was analyzed. RESULTS: A total of 10080 patients were included, among which 311 (3.1%) had positive surgical margins. pT3-4, pN+ and M1 were independent risk factors for positive margins, and a tumor in the middle of the stomach was a protective factor (p < 0.05). The 5-year overall survival (OS) rates of the patients with positive and negative margins after propensity score matching (PSM) were 24.2% and 36.8%, respectively (p < 0.001). For M0 patients, the 5-year OS of the margin-positive patients was lower than that of the margin-negative patients, and was higher than that of patients with M1. For the M1 patients, no statistically significant difference in 5-year OS was noted between patients with positive and negative margins. Age, positive margins, tumor location, pN+, and M1 were independent prognostic factors for OS in patients undergoing gastrectomy, and pN2-3 and M1 stages were independent prognostic factors for patients with positive surgical margins. Postoperative chemotherapy could improve the 5-year OS in pN2-3 and M1 margin-positive patients (p < 0.05). CONCLUSION: The prognosis of M0 gastric cancer patients with positive surgical margins is poor, and it is recommended that these patients should undergo routine intraoperative frozen-section pathological examination to reduce the risk of positive surgical margins.

16.
Environ Toxicol ; 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31400064

RESUMO

The objective of the present study was to explore the effects of environmental chemicals, such as methyl mercury, paraquat, and bisphenol A, on cell proliferation and apoptosis, as well as the expression levels of neuronal differentiation-related genes in neural stem cells (NSCs). NSCs originated from human umbilical cord blood (HUCB-NSCs) were used as cell models in the current study. CCK-8 and flow cytometry experiments were performed to assess the effects of methyl mercury, paraquat, and bisphenol A on the proliferation and apoptosis of HUCB-NSCs at different processes, including proliferation and differentiation stages. The expressions of neuronal differentiation-related genes were determined by reverse transcription-polymerase chain reaction and western blot analysis. The results showed that methyl mercury, paraquat, and bisphenol A treatments significantly inhibited cell proliferation and induced cell apoptosis in HUCB-NSCs, as well as decreased the expressions of Oct4, Gdf3, and Sox1, whereas increased Pax6 and Ngn1 expressions at both mRNA and protein levels. In conclusion, this study demonstrates that environmental chemicals can impair the proliferation and differentiation of NSCs, which may cause abnormal development of the nervous system.

17.
Alcohol Clin Exp Res ; 43(8): 1790-1800, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31373701

RESUMO

BACKGROUND: Alcohol consumption is associated with poor health outcomes in women living with HIV (WLWH), but whether medication can help to reduce drinking in non-treatment-seeking women or whether reduction in drinking improves HIV outcomes is unclear. We conducted a randomized clinical trial (RCT) of daily oral naltrexone (50 mg) versus placebo in WLWH who met criteria for current unhealthy alcohol use. METHODS: WLWH with current unhealthy alcohol use (>7 drinks/wk or >3 drinks/occasion) were randomly assigned to daily oral naltrexone 50 mg (n = 96) or placebo (n = 98) for 4 months. Drinking outcomes, including the proportion of women who reduced (

18.
J Vasc Res ; : 1-13, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31390638

RESUMO

BACKGROUND: Ca2+ plays an important role in the regulation of vasoconstriction. Ca2+ signaling is regulated by a number of Ca2+-handling proteins. However, whether differences in Ca2+ handling affect the regulation of vasoconstriction in different arteries remains elusive. OBJECTIVE: To determine whether differences in Ca2+ handling affect the response to vasoconstrictors in different arteries. METHODS: Arterial ring contraction was measured using a Multi Myograph System. Vascular smooth muscle cells (VSMCs) were digested with type 2 collagenase in DMEM, then intracellular calcium concentration was measured with the Ca2+ probe fluo-4/AM in the isolated cells. Calcium-related proteins were assayed by Western blotting. RESULTS: Phenylephrine did not induce -coronary arterial contraction. There were differences in -5-hydroxytryptamine, 9,11-dideoxy-11a,9a-epoxymethano-prostaglandin F2a, and endothelin 1-induced vasoconstriction in different solutions between coronary and renal arteries. Vasoconstrictions in the presence of Bay K8644 were stronger in coronary than in renal arteries. Store-operated calcium (SOC) channels could mediate Ca2+ influx in VSMCs of both groups. SOC channels did not participate in the contraction of coronary arteries. In addition, there were significant differences in the expressions of receptors and ion channels between the two groups. CONCLUSIONS: Ca2+ handling contributed to the different responses to vasoconstrictors between coronary and renal arteries.

19.
AIDS Behav ; 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31392442

RESUMO

HIV-related stigma is associated with many negative health outcomes among people living with HIV (PLHIV). The theory of intersectionality suggests that the interactions of social identities affect PLHIV's experiences of stigma. This study aims to identify individual and interactive marginalized-group identities correlated with enacted HIV-related stigma among PLHIV in Florida. The sample (n = 932) was majority male (66.6%), Black (58.5%), and non-Latino (80.2%) with 53% reporting experiences of HIV-related stigma. In multinomial regression models, the interaction between race and ethnicity was significant where non-White Latinos had higher odds of experiencing high levels of enacted stigma [AOR (CI) 7.71 (2.41, 24.73), p < 0.001] compared to white non-Latinos. Additionally, racial minorities were less likely to have experienced moderate or high levels of enacted stigma [AOR (CI) 0.47 (0.31, 0.72), p < 0.001; AOR (CI) 0.39 (0.22, 0.70), p = 0.002, respectively]. Moreover, women had higher odds of experiencing high levels of enacted stigma [AOR (CI) 2.04 (1.13, 3.67), p = 0.018]. The results suggest that intersectionality is important to consider in HIV-related stigma research and future interventions.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31338946

RESUMO

Axially chiral 2-arylpyrrole frameworks are efficiently accessed through a direct chirality transfer strategy by rapid cyclization of enantioenriched atropisomeric alkenes, which are generated by organocatalytic asymmetric N-alkylation reactions. This approach accommodates a broad scope of substrates with remarkably high chirality transfer efficiency, affording novel atropisomers with a fully substituted pyrrole moiety and high enantiopurities. Given the enantioenriched atropisomeric alkenes, novel heterocyclic 2-arylazepine atropisomers were realized through a rationally designed ene reaction.

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