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1.
IEEE Trans Vis Comput Graph ; 26(1): 1043-1053, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31478858

RESUMO

Experts in data and physical sciences have to regularly grapple with the problem of competing models. Be it analytical or physics-based models, a cross-cutting challenge for experts is to reliably diagnose which model outcomes appropriately predict or simulate real-world phenomena. Expert judgment involves reconciling information across many, and often, conflicting criteria that describe the quality of model outcomes. In this paper, through a design study with climate scientists, we develop a deeper understanding of the problem and solution space of model diagnostics, resulting in the following contributions: i) a problem and task characterization using which we map experts' model diagnostics goals to multi-way visual comparison tasks, ii) a design space of comparative visual cues for letting experts quickly understand the degree of disagreement among competing models and gauge the degree of stability of model outputs with respect to alternative criteria, and iii) design and evaluation of MyriadCues, an interactive visualization interface for exploring alternative hypotheses and insights about good and bad models by leveraging comparative visual cues. We present case studies and subjective feedback by experts, which validate how MyriadCues enables more transparent model diagnostic mechanisms, as compared to the state of the art.

2.
Eur J Pharm Sci ; 141: 105093, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648049

RESUMO

Reaction phenotyping is a method commonly used for characterizing drug metabolism. It determines the drug metabolic pathways and ratios by measuring the metabolized fractions of individual enzymes. However, currently published results have focused on cytochrome P450s (CYPs), while not considering phase II metabolism. Therefore, the morphinan analgesic, nalbuphine, primarily metabolized in the liver via CYPs and UDP-glucuronosyltransferases (UGTs), was selected as a model drug to establish a dual-phase platform to elucidate its comprehensive metabolic pathway. Enzyme kinetics was studied using 8 common recombinant (r)CYPs, 10 rUGTs, and pooled human liver microsomes. The overall fraction of nalbuphine metabolized by each isozyme was evaluated by determining parent drug depletion. Finally, in vitro-in vivo correlation was validated in animal studies. Fluconazole, a specific UGT2B7 inhibitor, was administered orally to rats to determine the pharmacokinetic effects on nalbuphine and nalbuphine metabolites. Seventy-five percent and 25% of nalbuphine was metabolized by UGTs and CYPs, respectively. UGT2B7, UGT1A3, and UGT1A9 were primarily responsible for nalbuphine glucuronidation; only UGT2B7 produced nalbuphine-6-glucuronide. CYP2C9 and CYP2C19 were the two CYP isozymes that produced 3'-hydroxylnalbuphine and 4'-hydroxylnalbuphine. In vivo, the maximum serum concentration (Cmax) and area under the curve (AUC) of nalbuphine increased 12.4-fold and 13.2-fold, respectively, with fluconazole co-administration. A dual system platform for drug metabolism was successfully established in this study and was used to generate a complete metabolic scheme for nalbuphine. This platform has been verified by in vivo evaluations and can be utilized to study drugs that undergo multisystem metabolism.

3.
Gene ; 722: 144076, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31454538

RESUMO

N6-methyladenosine (m6A) is the most prevalent internal modification in mammalian mRNAs and methyltransferase-like 3 (METTL3) is a vital methyltransferase in m6A modification. Here, this study tries to discover the regulatory role of METTL3 and its mechanism in the breast cancer tumorigenesis. Results found that METTL3 was up-regulated in the breast cancer tissue and cells. In vivo and vitro, METTL3 knockdown could decrease the methylation level, reduce the proliferation, accelerate the apoptosis and inhibited the tumor growth. Moreover, we found that Bcl-2 acted as the target of METTL3, thereby regulating the proliferation and apoptosis of breast cancer. This study could reveal the potential mechanism of m6A modification in the breast cancer tumorigenesis, providing potential drug targets in the treatment.


Assuntos
Neoplasias da Mama/enzimologia , Metiltransferases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Apoptose , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Feminino , Humanos , Metiltransferases/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
4.
Mol Phylogenet Evol ; 142: 106641, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31605813

RESUMO

The family Caprifoliaceae s.l. is an asterid angiosperm clade of ca. 960 species, most of which are distributed in temperate regions of the northern hemisphere. Recent studies show that the family comprises seven major clades: Linnaeoideae, Zabelia, Morinoideae, Dipsacoideae, Valerianoideae, Caprifolioideae, and Diervilloideae. However, its phylogeny at the subfamily or genus level remains controversial, and the backbone relationships among subfamilies are incompletely resolved. In this study, we utilized complete plastome sequencing to resolve the relationships among the subfamilies of the Caprifoliaceae s.l. and clarify several long-standing controversies. We generated and analyzed plastomes of 48 accessions of Caprifoliaceae s.l., representing 44 species, six subfamilies and one genus. Combined with available Caprifoliaceae s.l. plastomes on GenBank and 12 outgroups, we analyzed a final dataset of 68 accessions. Genome structure was strongly conserved in general, although the boundaries between the Inverted Repeat were found to have contracted across Caprifoliaceae s.l. to exclude rpl2, rps19, and ycf1, all or parts of which are typically present in the IR of most angiosperms. The ndhF gene was found to have been inverted in all plastomes of Adoxaceae. Phylogenomic analyses of 68 complete plastomes yielded a highly supported topology that strongly supported the monophyly of Zabelia and its sister relationship to Morinoideae. Moreover, a clade of Valerianoideae + Dipsacoideae was recovered as sister to a clade of Linnaeoideae + Zabelia + Morinoideae clade, and Heptacodium was sister to remaining Caprifolioideae. The Diervilloideae and Caprifolioideae were successively sister to all other Caprifoliaceae s.l. Major lineages of Caprifoliaceae s.l. were estimated to have diverged from the Upper Cretaceous to the Eocene (50-100 Ma), whereas within-genus diversification was dated to the Oligocene and later, concomitant with global cooling and drying. Our results demonstrate the power of plastid phylogenomics in improving estimates of phylogeny among genera and subfamilies, and provide new insights into plastome evolution across Caprifoliaceae s.l.

5.
Methods Mol Biol ; 2062: 401-415, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31768987

RESUMO

The RNA exosome is a multisubunit complex typically composed of a catalytically inactive core and the Rrp44 protein, which contains 3'-to-5' exo- and endo-RNase activities. With assistance from nuclear or cytoplasmic cofactors, functional studies implicated the exosome as a critical player in the turnover of almost all RNA species, including mRNAs, rRNA, tRNAs, and other noncoding RNAs. Here, we describe the purification of the yeast 10-subunit exosome and 11-subunit Exosome-Ski7, as well as subsequent sample screening by negative staining EM and structural analysis by cryo-EM.

6.
J Cell Biochem ; 121(1): 661-671, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31385362

RESUMO

Glioblastoma multiforme (GBM) is a refractory tumor with poor prognosis and requires more effective treatment regimens. It has been confirmed that long noncoding RNAs (lncRNAs) substantially regulate various human disease including GBM. However, the biological roles and its underlying molecular mechanisms still need to be further investigated. In this study, the biological function and potential molecular mechanism of lncHAS2-AS1 in GBM were explored. It was discovered that HAS2-AS1 was elevated in glioma tissues and correlated with the prognosis of patients with glioma. Reduction of HAS2-AS1 suppressed the migration and invasion in vitro and in vivo. The transcription factor STAT1 could raise HAS2-AS1 by binding to its promoter region. Besides, HAS2-AS1 could adjust PRPS1 via sponging miR-608 in a direct manner. On the whole, the results of this study evidence that HAS2-AS1 is an oncogene and a potential therapeutic target for GBM.

7.
J Nanosci Nanotechnol ; 20(4): 2442-2451, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492260

RESUMO

Two methods of TiO2 addition were applied to prepare hydroxyapatite/TiO2 (HA/TiO2) composite, i.e., in-situ hydrolysis TiO2 in HA powders (N-HA/TiO2) and mixing commercial nano-sized HA and TiO2 powder (C-HA/TiO2). Effects of TiO2 addition methods and sintering temperatures on phase, microstructure and microhardness were investigated for pressureless sintered HA/TiO2 composites, and pure HA was investigated for comparison. Results show that TiO2 from both in-situ hydrolysis and mixing commercial powder presented similar effects on phase structures and composition, and trended to chemically react with HA in the HA/TiO2 composites at high sintering temperature. Weight loss for different composites was investigated by thermal analysis. Sintering behavior for two different composite was also discussed. The TiO2 from in-situ hydrolysis can effectively enhance the TiO2 distribution and densification for the N-HA/TiO2 composites. Both two different composites showed typical grain growth and pore formation with the increase of sintering temperature. The N-HA/TiO2 composite had a lower porosity, higher shrinkage and microhardness than that of C-HA/TiO2 composite at sintering temperature from 700 °C to 1100 °C.

8.
Chemosphere ; 238: 124607, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524603

RESUMO

A fluoride exposure mouse model is established to evaluate the relationship between mitochondrial respiratory chain complexes and renal dysfunction. Morphological changes in kidney tissues were observed. Renal function and cell proliferation in the kidneys were evaluated. The expression of mitochondrial fusion protein including mitofusin-1 (Mfn1) and optic atrophy 1 (OPA1), and mitochondrial respiratory chain complex subunits, including NDUFV2, SDHA, CYC1 and COX Ⅳ, were detected via real-time polymerase chain reaction, immunohistochemistry staining and Western blot, respectively. Results showed that the structures of renal tubule, renal glomerulus and renal papilla were seriously damaged. Renal function was impaired, and cell proliferation was remarkably inhibited by excessive fluoride in kidney. The mRNA and protein expression levels of Mfn1, OPA1, NDUFV2, CYC1 and COX Ⅳ were significantly increased after excessive fluoride exposure. However, the mRNA and protein expression of SDHA significantly decreased. Overall, our findings revealed that excessive fluoride can damage kidney structure, inhibit renal cell proliferation, interfere with the expression of mitochondrial respiratory chain complexes and elevate mitochondrial fusion. Consequently, renal function disorder occurred.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31674119

RESUMO

Engineering the coordination environments and electronic structures of single-atom catalysts (SACs) to enhance their catalytic activity remains great challenge. Herein, we found that the reaction of precursors containing both nitrogen and oxygen atoms with Ni(II) under 500°C can generate a N/O mixing coordinated Ni-N3O SAC, in which the oxygen atom can be gradually removed under high temperature due to weaker Ni-O interaction, resulting in a vacancy-defect Ni-N3-V SAC at Ni site under 800°C. While the reaction of Ni(II) with the precursor simply containing nitrogen atoms can only obtain a none-vacancy-defect Ni-N4 SAC. Both the results of experimental and DFT calculations reveal that the presence of a vacancy-defect in Ni-N3-V SAC can dramatically boost the electrocatalytic activity for CO2 reduction, with extremely high CO2 reduction current density of 65 mA/cm2 and high Faradaic efficiency over 90% at -0.9 V vs RHE, as well as a record high turnover frequency of 1.35×105 h-1, much higher than those of Ni-N4 SAC, and being one of the best reported electrocatalysts for CO2-to-CO conversion to date.

10.
Opt Express ; 27(19): 26924-26939, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674563

RESUMO

High-performance GeSn multiple-quantum-well (MQW) photodiode is demonstrated on a 200 mm Ge-on-insulator (GeOI) photonics platform for the first time. Both GeSn MQW active layer stack and Ge layer (top Ge layer of GeOI after bonding) were grown using a single epitaxy step on a standard (001)-oriented Si substrate (donor wafer) using a reduced pressure chemical vapor deposition (RPCVD). Direct wafer bonding and layer transfer technique were then employed to transfer the GeSn MQW device layers and Ge layer to a 200 mm SiO2-terminated Si handle substrate. The surface illuminated GeSn MQW photodiode realized on this platform exhibits an ultra-low leakage current density of 25 mA/cm2 at room temperature and an enhanced photo sensitivity at 2 µm of 30 mA/W as compared to a GeSn MQW photodiode on Si at 2 µm. The underlying GeOI platform enables monolithic integration of a complete suite of photonics devices operating at 2 µm band, including GeOI strip waveguides, grating couplers, micro-ring modulators, Mach-Zehnder interferometer modulators, etc. In addition, Ge CMOS circuits can also be realized on this common platform using a "photonic-first and electronic-last" processing approach. In this work, as prototype demonstration, both Ge p- and n-channel fin field-effect transistors (FinFETs) were realized on GeOI simultaneously with decent static electrical characteristics. Subthreshold swings of 150 and 99 mV/decade at |VD| = 0.1 V and drive currents of 91 and 10.3 µA/µm at |VG-VTH| = 1 V and |VD| = 0.75 V were achieved for p- and n-FinFETs, respectively. This works illustrates the potential of integrating GeSn (as photo detection material) on GeOI platform for Ge-based optoelectronics integrated circuits (OEICs) targeting communication applications at 2 µm band.

11.
Liver Int ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674705

RESUMO

BACKGROUND & AIMS: Trends in long-term mortality rates for viral hepatitis in East and Southeast Asia have been rarely reported. The aim of our study was to explore the long-term trends in viral hepatitis mortality rates in East and Southeast Asian countries between 1987 and 2015 and provide predictions of mortality to 2030. METHODS: We obtained viral hepatitis mortality data from the WHO Mortality Database for 7 East and Southeast Asian countries between 1987 and 2015.We produced choropleth maps of viral hepatitis mortality rates in 1987 and 2015 in East and Southeast Asia to illustrate geographic variations. We made predictions of mortality rates for each included country until the year 2030 using a series of joinpoint models. RESULTS: Viral hepatitis mortality rates declined in China (the average annual percent change (AAPC)=-5.1%, 95% CI: -7.5, -2.6), Singapore (AAPC=-5.4%, 95% CI: -7.5, -3.2), and the Philippines (AAPC=-3.4%, 95% CI: -4.9, -1.8). In contrast, Japan, the Republic of Korea, and Malaysia have experienced increasing trends in mortality rates, followed by decreasing trends. Our predictions indicate that all countries will experience slight to moderate downward trends until 2030. CONCLUSION: Favorable decreasing trends have been noted in East and Southeast Asian countries, which may not only inform the control and management of viral hepatitis in this region but also guide the prevention of viral hepatitis deaths in another region with a similar viral hepatitis epidemic.

12.
Plant Cell Physiol ; 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31670803

RESUMO

Pentatricopeptide repeat (PPR) proteins are helical repeat RNA binding proteins that function in RNA processing by conferring sequence-specific RNA binding activity. Owing to lethality of PPR mutants, functions of many PPR proteins remain obscure. Here, we report the function of PPR20 in intron splicing in mitochondria and its role in maize seed development. PPR20 is a P-type PPR protein targeted to mitochondria. The ppr20 mutants display slow embryo and endosperm development. Null mutation of PPR20 severely reduces the cis-splicing of mitochondrial nad2 intron 3, resulting in reduction in the assembly and activity of mitochondrial complex I. The ppr20-35 allele with a Mu insertion in the N-terminal region shows a much weaker phenotype. Molecular analyses revealed that the mutant produces a truncated transcript, coding for PPR20ΔN120 lacking the N-terminal 120 amino acids. Subcellular localization revealed that PPR20ΔN120: GFP is able to target to mitochondria as well, suggesting the sequence diversity of the mitochondrial targeting peptides. Another mutant zm_mterf15 was also found to be impaired in the splicing of mitochondrial nad2 intron 3. Further analyses are required to identify the exact function of PPR20 and Zm_mTERF15 in the splicing of nad2 intron 3.

13.
Biomolecules ; 9(12)2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31771142

RESUMO

In this work, a monoclonal antibody-based indirect competitive enzyme-linked immunosorbent assay (icELISA) was established to detect tylosin and tilmicosin in milk and water samples. A sensitive and specific monoclonal antibody was prepared by rational designed hapten, which was achieved by directly oxidizing the aldehyde group on the side chain of tylosin to the carboxyl group. Under the optimized conditions, the linear range of icELISA for tylosin and tilmicosin were 1.3 to 17.7 ng/mL and 2.0 to 47.4 ng/mL, with half-maximal inhibition concentration (IC50) values of 4.7 and 9.6 ng/mL, respectively. The cross-reactivity with other analogues of icELISA was less than 0.1%. The average recoveries of icELISA for tylosin and tilmicosin ranged from 76.4% to 109.5% in milk and water samples. Besides, the detection results of icELISA showed good correlations with HPLC-MS/MS. The proposed icELISA was satisfied for rapid and specific screening of tylosin and tilmicosin residues in milk and water samples.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31776129

RESUMO

Transformation of follicular lymphoma (FL) into B-cell lymphoblastic lymphoma/leukemia (LL) is rare and results in greatly increased aggressiveness of clinical course. Here we present extensive molecular analysis of this unusual transformation, including immunoglobulin (Ig) gene rearrangement studies, cytogenetic analysis, and whole exome sequencing (WES) of the patient's FL, LL, and normal cells. While FL showed marked somatic hypermutation (SHM) of the Ig genes, SHM appeared to be even more extensive in LL. Cytogenetically, four translocations were identified in the LL: two involving BCL-2, and one each in BCL-6 and c-MYC genes, with two of these, the BCL-6 and one of the BCL-2 gene rearrangements, already seen at the FL stage. WES identified 751 single nucleotide variants with high allelic burden in the patient's cells, with the vast majority (575) present exclusively at the LL stage. Of note, a TAF3 gene mutation was shared by normal, FL and LL tissue, perhaps predisposing this young patient to develop FL. In turn, the KMT2D nonsense mutation was identified in both FL and LL, and therefore may have contributed directly to lymphomagenesis. Mutations in KDM6A, SMARCA4, CBX1, and JMY were specific to the LL stage, possibly contributing to the LL transformation. Functionally, these identified mutations may lead to dysregulation of DNA repair, transcription, and cell differentiation. Thus, these genetic changes, together with the identified chromosomal translocations, may have contributed to lymphoma development and progression. Our findings may improve the mechanistic understanding of the FL-LL transformation, and may have therapeutic implication for this aggressive disease.

15.
FEMS Microbiol Lett ; 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31778183

RESUMO

Rana amurensis and R. dybowskii occupy similar habitats. As temperatures decrease with the onset of winter, both species migrate to ponds for hibernation. Our goal was to determine whether different species possess different intestinal microbiota under natural winter fasting conditions. We used high-throughput Illumina sequencing of 16S rRNA gene sequences to analyse the diversity of intestinal microbes in the two species. The dominant gut bacterial phyla in both species were Bacteroidetes, Proteobacteria, and Firmicutes. LEfSe analysis revealed significant enrichment of Proteobacteria in R. amurensis and Firmicutes in R. dybowskii. There were significant differences in the gut microbiota composition between species. The core OTU numbers in R. amurensis and R. dybowskii and shared by the two species were 106, 100 and 36, respectively. The study indicates that the intestinal bacterial communities of the two frog species are clearly different. Phylum-level analysis showed that R. amurensis was more abundant in Proteobacteria and Verrucomicrobia than was R. dybowskii. This is the first study of the composition and diversity of the gut microbiota of these two species, providing important insights for future research on the gut microbiota and the role of these bacterial communities in frogs.

16.
Redox Biol ; 28: 101373, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31731100

RESUMO

It has been shown that anti-inflammatory cytokines interleukin-35 (IL-35) and IL-10 could inhibit acute endothelial cell (EC) activation, however, it remains unknown if and by what pathways IL-35 and IL-10 could block atherogenic lipid lysophosphatidylcholine (LPC)-induced sustained EC activation; and if mitochondrial reactive oxygen species (mtROS) can differentiate mediation of EC activation from trained immunity (innate immune memory). Using RNA sequencing analyses, biochemical assays, as well as database mining approaches, we compared the effects of IL-35 and IL-10 in LPC-treated human aortic ECs (HAECs). Principal component analysis revealed that both IL-35 and IL-10 could similarly and partially reverse global transcriptome changes induced by LPC. Gene set enrichment analyses showed that while IL-35 and IL-10 could both block acute EC activation, characterized by upregulation of cytokines/chemokines and adhesion molecules, IL-35 is more potent than IL-10 in suppressing innate immune signatures upregulated by LPC. Surprisingly, LPC did not induce the expression of trained tolerance itaconate pathway enzymes but induced trained immunity enzyme expressions; and neither IL-35 nor IL-10 was found to affect LPC-induced trained immunity gene signatures. Mechanistically, IL-35 and IL-10 could suppress mtROS, which partially mediate LPC-induced EC activation and innate immune response. Therefore, anti-inflammatory cytokines could reverse mtROS-mediated acute and innate immune trans-differentiation responses in HAECs, but it could spare metabolic reprogramming and trained immunity signatures, which may not fully depend on mtROS. Our characterizations of anti-inflammatory cytokines in blocking mtROS-mediated acute and prolonged EC activation, and sparing trained immunity are significant for designing novel strategies for treating cardiovascular diseases, other inflammatory diseases, and cancers.

17.
Ultramicroscopy ; 209: 112887, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31739190

RESUMO

A new design scheme for ultrafast transmission electron microscopy (UTEM) has been developed based on a Schottky-type field emission gun (FEG) at the Institute of Physics, Chinese Academy of Sciences (IOP CAS). In this UTEM setup, electron pulse emission is achieved by integrating a laser port between the electron gun and the column and the resulting microscope can operate in either continuous or pulsed mode. In pulsed mode, the optimized electron beam properties are an energy width of ~0.65 eV, micrometer-scale coherence lengths and sub-picosecond pulse durations. The potential applications of this UTEM, which include electron diffraction, high-resolution imaging, electron energy loss spectroscopy, and photon-induced near-field electron microscopy, are demonstrated using ultrafast electron pulses. Furthermore, we use a nanosecond laser (~10 ns) to show that the laser-driven FEG can support high-quality TEM imaging and electron holography when using a stroboscopic configuration. Our results also indicate that FEG-based ultrafast electron sources may enable high-performance analytical UTEM.

18.
Nat Commun ; 10(1): 5331, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767849

RESUMO

Wave trapping and manipulation are at the heart of modern integrated photonics and acoustics. Grand challenges emerge on increasing the integration density and reducing the wave leakage/noises due to fabrication imperfections, especially for waveguides and cavities at subwavelength scales. The rising of robust wave dynamics based on topological mechanisms offers possible solutions. Ideally, in a three-dimensional (3D) topological integrated chip, there are coexisting robust two-dimensional (2D) interfaces, one-dimensional (1D) waveguides and zero-dimensional (0D) cavities. Here, we report the experimental discovery of such a dimensional hierarchy of the topologically-protected 2D surface states, 1D hinge states and 0D corner states in a single 3D system. Such an unprecedented phenomenon is triggered by the higher-order topology in simple-cubic sonic crystals and protected by the space group [Formula: see text]. Our study opens up a new regime for multidimensional wave trapping and manipulation at subwavelength scales, which may inspire future technology for integrated acoustics and photonics.

19.
Vet Parasitol ; 276: 108991, 2019 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-31770701

RESUMO

Eimeria tenella, an obligate intracellular parasite, can actively invade the cecal epithelial cells of chickens and cause severe enteric disease. Eukaryotic elongation factor 2 (eEF2) plays a major role in protein synthesis and cell survival. This study aims to explore the exact mechanisms underlying diclazuril inhibition in second-generation merozoites of E. tenella. The eEF2 cDNA of the second-generation merozoites of E. tenella (EtEF2) was cloned by reverse transcriptase polymerase chain reaction and rapid amplification of cDNA ends. Diclazuril-induced expression profiles of EtEF2 were also analyzed. The cloned full-length cDNA (2893 bp) of the EtEF2 nucleotide sequence encompassed a 2499 bp open reading frame (ORF) that encoded a polypeptide of 832 residues with an estimated molecular mass of 93.12 kDa and a theoretical isoelectric point of 5.99. The EtEF2 nucleotide sequence was submitted to the GenBank database with the accession number KF188423. The EtEF2 protein sequence shared 99 % homology with the eEF2 sequence of Toxoplasma gondii (GenBank XP_002367778.1). The GTPase activity domain and ADP-ribosylation domain were conserved signature sequences of the eEF2 gene family. The changes in the transcriptional and translational levels of EtEF2 were detected through quantitative real-time PCR and Western blot analyses. The mRNA expression level of EtEF2 was 2.706 fold increases and the protein level of EtEF2 was increased 67.31 % under diclazuril treatment. In addition, the localization of EtEF2 was investigated through immunofluorescence assay. Experimental results demonstrated that EtEF2 was distributed primarily in the cytoplasm of second-generation merozoites, and its fluorescence intensity was enhanced after diclazuril treatment. These findings indicated that EtEF2 may have an important role in understanding the signaling mechanism underlying the anticoccidial action of diclazuril and could be a promising target for novel drug exploration.

20.
BMJ Open ; 9(10): e028464, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31672709

RESUMO

INTRODUCTION: Postoperative pulmonary complications (PPCs), strongly associated with higher mortality risk, can develop in up to 58% of patients undergoing abdominal surgery. More and more evidence shows that the use of a lung-protective ventilation strategy has a lung protection effect in patients undergoing abdominal surgery, however, the role of positive end-expiratory pressure (PEEP) during the intraoperative period in preventing PPCs for laparoscopic surgery is not clearly defined. METHODS AND ANALYSIS: A total of 208 patients with a high risk of PPC, undergoing laparoscopic abdominal surgery, will be enrolled and randomised into a standard PEEP (6-8 cm H2O) group and a low PEEP (≤2 cm H2O) group. Both groups will receive a fraction of inspired oxygen of 0.50 and a tidal volume of 8 mL/kg ideal body weight (IBW). Standard perioperative fluid management and analgesic treatments are applied in both groups. The primary end point is PPC within 7 days after surgery. Secondary end points are the modified Clinical Pulmonary Infection Score, postoperative extrapulmonary complications, postoperative surgical complications, intensive care unit length of stay, hospital length of stay, 30-day mortality. ETHICS AND DISSEMINATION: The study was approved by the Ethics Committee of Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medicine College) (registration number KY2018026) on 22 October 2018. The first participant was recruited on 15 April 2019 and the estimated completion date of the study is October 2021. The results of this trial will be submitted to a peer-reviewed journal. TRIAL REGISTRATION NUMBER: http://www.chictr.org.cn, ID: ChiCTR1800019865. Registered on 2 December 2018; preresults.

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