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1.
Artigo em Inglês | MEDLINE | ID: mdl-32005735

RESUMO

The AdhR regulatory protein is an activator of σ54-dependent transcription of adhA1 and adhA2 genes, which are required for alcohol synthesis in C. beijerinckii Here, we identified the signal perceived by AdhR and determined the regulatory mechanism of AdhR activity. By assaying the activity of AdhR in N-terminally truncated forms, a negative control mechanism of AdhR activity was identified, in which the central AAA+ domain is subject to repression by the N-terminal GAF and PAS domains. Binding of Fe2+ to the GAF domain was found to relieve intramolecular repression and stimulate the ATPase activity of AdhR, allowing the AdhR to activate transcription. This control mechanism enables AdhR to regulate transcription of adhA1 and adhA2 in response to cellular redox status. The mutants deficient in AdhR or σ54 showed large shifts in intracellular redox state indicated by NADH/NAD+ ratio under conditions of increased electron availability or oxidative stress. We demonstrated the Fe2+-activated transcriptional regulator AdhR and σ54 control alcohol synthesis to maintain redox homeostasis in clostridial cells. Expression of N-terminally truncated forms of AdhR resulted in improved solvent production by C. beijerinckii IMPORTANCESolventogenic clostridia are anaerobic bacteria that can produce butanol, ethanol, and acetone, which can be used as biofuels or building block chemicals. Here we showed that AdhR, a σ54-dependent transcriptional activator, senses the intracellular redox status and controls alcohol synthesis in Clostridium beijerinckii AdhR provides a new example of a GAF domain coordinating a mononuclear non-heme iron to sense and transduce the redox signal. Our study reveals a previously unrecognized functional role of σ54 in control of cellular redox balance and provides new insights into redox signaling and regulation in clostridia. Our results reveal AdhR as a novel engineering target for improving solvent production by C. beijerinckii and other solventogenic clostridia.

2.
Neurology ; 94(7): e762-e763, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32015177
3.
Mol Cell Biochem ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32056105

RESUMO

This study evaluated the cardioprotective effects of a miR-1275 mimic in a rat model of myocardial ischemia-reperfusion (I/R)-induced myocardial injury (MI). Three groups of rats were established: a sham-operated group, a MI group and a MI+miR-1275 group pretreated for 1 week i.p. with a miR-1275 mimic at a concentration of 30 pmol/mL. MI was induced by I/R. The levels of myocardial enzymes in serum were estimated in all rats, together with haemodynamic functions. The effects of the miR-1275 mimic were determined based on the serum concentrations of inflammatory mediators in the treated vs. sham and MI rats. In addition, western blot assay and immunohistochemical analyses were performed to examine the effect of the miR-1275 mimic on the Wnt/NF-kB signalling pathway in MI rats. Treatment with the miR-1275 mimic attenuated the altered levels of myocardial enzymes and haemodynamic functions seen in MI rats. The myocardial infarct was smaller in rats treated with the miR-1275 mimic than in MI rats. The miR-1275 mimic also reduced myocardiocyte apoptosis and ameliorated the altered Wnt/KF-kB pathway. These results demonstrate the efficacy of the miR-1275 mimic in preventing myocardial I/R-induced MI in rats, by regulating the Wnt/NF-κB pathway.

4.
Plant Biotechnol J ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32012429

RESUMO

Seed vigour is an important trait for direct seeding in rice. In this study, indole-3-acetate beta-glucosyltransferase OsIAGLU was cloned in rice, and its roles on seed vigour were mainly investigated. Disruption of OsIAGLU resulted in low seed vigour in rice. Quantitative RT-PCR analysis showed that the expressions of OsIAGLU were relatively higher in the late developing and the early germinating seeds and were significantly induced by indole-3-acetic acid (IAA) and abscisic acid (ABA). Transcriptome analysis revealed that the IAA- and ABA-related genes were involved in the OsIAGLU regulation of seed vigour in rice. The higher levels of free IAA and ABA were identified in germinating seeds of osiaglu mutants compared to wild-type (WT) plants. When treated with exogenous IAA and ABA, the osiaglu mutants and WT plants showed sensitivity to ABA while not IAA, but the exogenous IAA amplified ABA-induced reduction of seed vigour in rice. The continuously higher expressions of ABA-INSENSITIVE 3 (OsABI3) and OsABI5 occurred in germinating seeds of osiaglu mutants compared to WT plants. The regulation of seed vigour by OsIAGLU might be through modulating IAA and ABA levels to alert OsABIs expression in germinating seeds in rice. Based on analysis of single-nucleotide polymorphism data of rice accessions, two haplotypes of OsIAGLU that positively correlated with seed vigour were identified in indica accessions. This study provides important insights into the roles of OsIAGLU on seed vigour and facilitates the practical use of OsIAGLU in rice breeding.

5.
Psychiatry Res ; 285: 112817, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32035376

RESUMO

OBJECTIVES: We aimed to examine brain white matter integrity in children with ADHD. METHODS: In a cohort of children with ADHD (n = 83) and healthy controls (n = 122), we used tract-based spatial statistics on Diffusion Tensor Imaging (DTI) data to obtain the mean fractional anisotropy (FA) in 40 bilateral regions of interest (ROIs). Lateralization Index (LI) was calculated. The difference in LI between groups and correlations between the LI of each ROI and ADHD symptom scores as well as cognitive function were examined. RESULTS: Children with ADHD had significantly greater LI at the posterior thalamic radiation (PTR) compared with healthy controls (mean LI in ADHD = 0.0096; in Control = 0.0044, p = 0.0143), and LI of the external capsule (EC) was significantly correlated with inattention symptoms in both groups (ß = -0.00059, p = 0.0181). LI of the PTR was significantly correlated with inhibitory function in healthy controls (ß = -0.0008510, p = 0.0248), but not in children with ADHD. CONCLUSION: We found increased brain white matter asymmetry (leftward) in children with ADHD compared with healthy controls at the posterior thalamic radiation. Leftward lateralization of FA values at the external capsule was negatively correlated with ADHD symptoms in both children with ADHD and healthy controls.

6.
Rev Sci Instrum ; 91(1): 013706, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012644

RESUMO

Femoral neck-shaft angle (NSA) is the angle included by the femoral neck axis (FNA) and the femoral shaft axis (FSA), which is a critical anatomic measurement index for evaluating the biomechanics of the hip joint. Aiming at solving the problem that the physician's manual measurement of the NSA is time consuming and irreproducible, this paper proposes a fully automatic approach for evaluating the femoral NSA on radiographs. We first present an improved deep convolutional generative adversarial network to automatically segment the femoral region of interest on radiographs of the pelvis. Then based on the geometrical characteristic of the femoral shape, the FNA and FSA are fitted, respectively, and thus, the NSA can be evaluated conveniently. The average accuracy of the proposed approach for NSA evaluation is 97.24%, and the average deviation is 2.58° as compared to the measurements manually evaluated by experienced physicians. There is no significant statistical difference (P = 0.808) between the manual and automatic measurements, and Pearson's correlation coefficient is 0.904. It is validated that the proposed approach can provide an effective and reliable tool for automatically evaluating the NSA on radiographs.

7.
Sensors (Basel) ; 20(3)2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32033468

RESUMO

s: In this paper, the guided wave propagation behavior in damaged 30CrMo steel curved plates was investigated experimentally and numerically. The effects of the notch orientation, depth in the curved plate, as well as its radius, on the wave propagation characteristics were mainly analyzed by the amplitude distribution curves and the directivity diagrams of A0/S0 (zero-th order of the symmetric/antisymmetric Lamb wave) modes. An ellipse-based algorithm was compiled to locate the notches in the curved plates. Results show that the normalized S0 wave amplitude in the circumferential orientation was the largest, and it increases as notch depth increases in the axial orientation. The A0 wave amplitude in axial orientation was the largest, while it decreases with the increasing of notch depth in the other orientations. The normalized A0 wave amplitude in axial orientation increases with the increasing of radius. With the increasing of radius, the other normalized A0/S0 amplitudes linearly decreased for the other paths. The ellipse-based algorithm has high notch localization accuracy, and the notch localization error increase from 0.005% to 1.47% with the notch depth decreasing from 5 mm to 1 mm in the curved plates. For the curved plates with different radius, the maximum notch localization error is 1.20%. These satisfactory results demonstrate the effectiveness of the developed algorithm in locating damages in the researched structure.

8.
Biol Trace Elem Res ; 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32002792

RESUMO

Iron overload is harmful to health and associates with intracellular excessive reactive oxygen species (ROS) generation. Nobiletin (Nob) is known to be antioxidant and anti-inflammatory. However, whether Nob can protect endothelial cells against iron overload has not been studied, and the specific mechanism has not yet been elucidated. In this study, we have identified the protective effects of Nob, and its underlying molecular mechanism in human umbilical vein endothelial cells (HUVECs) suffered from iron overload via ROS/ADMA/DDAHII/eNOS/NO pathway. We found that compared with 50 µM iron dextran treatment, co-treatment with 20 µM Nob increased cell viability and decreased lactate dehydrogenase activity. Besides, Nob could upregulate DDAHII expression and activity, promote eNOS phosphorylation to produce more NO, reduce ADMA content, and therefore increase superoxide dismutase, catalase, and glutathione peroxidase activities, and decrease malondialdehyde level and ROS generation. Nob also inhibited mitochondrial permeability transition pore (mPTP) openness and cleaved caspase-3 expression, and decreased apoptosis induced by iron overload. These results were consistent when Nob was replaced by the positive control reagents L-arginine (a competitive substrate of ADMA), cyclosporin A (an mPTP closing agent), or edaravone (a free radical scavenger). The addition of pAD/DDAHII-shRNA adenovirus reversed the above effects of Nob. These data suggested that the protective mechanism of Nob was to inhibit ROS burst, upregulate DDAHII expression and activity, promote eNOS phosphorylation, produce NO, reduce ADMA content, and ultimately alleviate iron overload damage in vascular endothelium.

9.
J Cell Physiol ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32052444

RESUMO

This study aimed to investigate the functional roles of kinesin family member 18B (KIF18B) in hepatocellular carcinoma (HCC) development, as well as the related molecular mechanisms. Tissue specimens were collected from 105 patients with HCC, and the messenger RNA (mRNA) and protein levels of KIF18B were detected using quantitative real-time polymerase chain reaction and immunohistochemistry assays, respectively. The χ2 test was performed to estimate the association of KIF18B with clinical characteristics of patients with HCC. Effects of KIF18B expression on biological behaviors of HCC cells were detected by clone formation, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, and transwell assays. The expression patterns of proteins were investigated using Western blot analysis. HCC tissues and cell lines showed significant upregulation of KIF18B at both mRNA and protein levels (p > .05, for all). Furthermore, the elevated KIF18B expression was positively correlated with the tumor-node-metastasis stage (p = .015) and lymph node metastasis (p = .007). Knockdown of KIF18B might suppress HCC cell clone formation, proliferation, migration, and invasion in vitro. Besides, the activity of Wnt/ß-catenin pathway was also significantly inhibited after the KIF18B knockdown. However, the antitumor actions caused by KIF18B knockdown might be reversed by lithium chloride treatment, which was the inducer of Wnt/ß-catenin-signaling pathway. KIF18B may serve as an oncogene in HCC through enhancing the activity of Wnt/ß-catenin pathway.

10.
Artigo em Inglês | MEDLINE | ID: mdl-32053072

RESUMO

Reconstruction of gene regulatory networks (GRN) plays an important role in understanding the complexity, functionality and pathways of biological systems, which could support the design of new drugs for diseases. Because differential equation models are flexible and strong, these models have been utilized to identify biochemical reactions and gene regulatory networks. This paper investigates the differential equation models for reverse engineering gene regulatory networks. We introduce three kinds of differential equation models, including ordinary differential equation (ODE), time-delayed differential equation (TDDE) and stochastic differential equation (SDE). ODE models include linear ODE, nonlinear ODE and S-system model. We also discuss the evolutionary algorithms, which are utilized to search the optimal structures and parameters of differential equation models. This investigation could provide a comprehensive understanding of differential equation models, and lead to the discovery of novel differential equation models.

11.
Acta Biomater ; 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32044457

RESUMO

Traditional cell therapy technology relies on the maximum expansion of primary stem cells in vitro, through multiple passages and potential differentiation protocols, in order to generate the abundance of cells needed prior to transplantation in vivo. Implantation of in vitro over-expanded and pre-differentiated cells typically results in poor cell survival and reduced regeneration capacity for tissue repair in vivo. We hypothesized that implantation of primary stem cells, after a short time culture in vitro (passage number ≤p3), in combination with controlled release of relevant growth factors would improve in vivo cell viability, engraftment and tissue regeneration. The goal of this study was to determine whether the release of myogenic growth factors from a heparin-hyaluronic acid gel (hp-HA gel) could enhance in vivo cell survival, in-growth and myogenic differentiation of human urine-derived stem cells (USC) with a corresponding enhancement in graft vascularization, innervation and regenerative properties. Human USC were obtained from healthy adult donors (n=6), expanded and then mixed with a hp-HA gel containing sets of growth factors known to enhance myogenesis (IGF1, HGF, PDGF-BB), neurogenesis (NGF, FGF) and angiogenesis (VEGF), or a cocktail with a combination of growth factors. Primary cultured USC (p3) mixed with the hp-HA gel and the various combinations of growth factors, were subcutaneously injected into athymic mice. In vivo cell survival, engraftment and functional differentiation within the host tissue were assessed. The implanted grafts containing USC and the growth factor cocktail showed the greatest number of surviving cells as well as increased numbers of cells that expressed myogenic and endothelial cell markers as compared to other groups 4 weeks after implantation. Moreover, the graft with USC and the growth factor cocktail showed increased numbers of blood vessels and infiltrating neurons. Thus, growth factors released in a controlled manner from an hp-HA gel containing USC efficiently improved in vivo cell survival and supported vascularization and myogenic differentiation within the grafts. This study provides evidence for the use of primary USC and growth factors in a hydrogel as a novel mode of cell therapy for the promotion of myogenic differentiation for the treatment of injured muscle tissue. Statement of Significance Cell therapies are a promising treatment option for neuromuscular dysfunction disorders. However, major limitations in cell retention and engraftment after implantation remain a hindrance to the use of stem cell therapy for the treatment of muscle injuries or diseased tissues. Implanted long-term in vitro cultured cells tend to demonstrate low rates of survival and tissue engraftment, lessened paracrine effects, and poor homing and differentiation. Human USC are an easily obtainable stem cell source that possess stem cell characteristics such as a robust proliferative potential, paracrine effects on neighboring cells, and multi-potential differentiation. In this study, we demonstrated that a combination of primary human USC with a cocktail of growth factors combined in a hyaluronic gel was optimal for cell survival and engraftment, including myogenic differentiation potential of USC, angiogenesis and host nerve fiber recruitment in vivo. The present study also demonstrated that the use of primary urine derived stem cells at early passages, without in vitro pre-differentiation, implanted in a hyaluronic-heparin hydrogel containing a cocktail of growth factors, provided an alternative safe site-specific delivery method for cell therapy.

12.
Sex Transm Dis ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32011419

RESUMO

BACKGROUND: Partner notification (PN) is an essential component of syphilis control and is recommended by Chinese Sexually Transmitted Disease guidelines. However, in China, studies examining local practice are limited. This study evaluated partner notification outcomes among persons with early syphilis infection in an urban district in China. METHODS: From 2011 to 2017, persons diagnosed with early syphilis were asked to participate in an evaluation of supportive patient referral partner services for all recent sex partners, and the contact and case finding indices were determined in Nanshan District, Shenzhen, China. RESULTS: During the study period, 642 index patients with early syphilis reported 1749 sex partners. Of those partners, 678 were potentially contactable and 525 (30%) were contacted. The overall contact index was 0.82. Among the 1749 partners reported, 1108 (63%) were described as casual partners and only 37 (3%) were contacted (contact index 0.13) compared to 641 partners who were either spouses and regular partners (contact index 1.37). Among those 525 partners contacted, 418 (80%) were tested and 205 (39%) were diagnosed with and treated for syphilis. Among those, 9 (4%) were primary, 26 (13%) were secondary, 16 (8%) were early latent, and 154 (49%) were other syphilis infections. The overall case finding index was 0.29. CONCLUSIONS: There is a need to improve PN practices in China, which include developing operational guidelines of PN and to develop and evaluate novel PN ways like using Internet-based strategy.

13.
Medicine (Baltimore) ; 99(3): e18888, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32011516

RESUMO

RATIONALE: The success of tyrosine kinase inhibitor (TKI) therapy has greatly prolonged the survival time of patients with chronic myeloid leukemia (CML), harboring the characteristic Philadelphia (Ph) chromosome. However, a fraction of patients, achieving complete cytogenetic response after TKI therapy, develop a myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) with additional clonal chromosomal abnormalities in Philadelphia-negative cells (CCA/Ph-). PATIENT CONCERNS: A 56-year-old woman with AML, developing from Philadelphia-negative CML after TKI therapy. She showed 6 kinds of somatic variants-CEBPA, ATRX, WT1, CSMD1, IKZF1, and LRP1B mutation after diagnosed as AML. DIAGNOSIS: The patient was diagnosed with chronic phase CML that developed to AML after achieving durable complete cytogenetic response (CCR) and major molecular response (MMR). INTERVENTIONS: The patient was treated with TKI therapy at the period of CML. When diagnosed with AML, she received induction chemotherapy regimens, consolidation therapy, and allogeneic hematopoietic stem cell transplantation subsequently. OUTCOMES: The patient has been CCR and MMR for nearly 4 years, and has achieved complete remission after intervention related to AML. She is now preparing for allogeneic hematopoietic stem cell transplantation. LESSONS: These rare occurrences highlight the importance of exploring the relevant pathogenesis of AML developing from CML after TKI therapy. In addition to monitoring molecular changes in the course of CML, cytogenetic analysis, or next-generation sequencing of CML patients should be performed.

14.
J Invest Dermatol ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31930972

RESUMO

Treponema pallidum (Tp) infection-induced immune responses can cause tissue damage. However, the underlying mechanism by which Tp infection induces immune response is unclear. Recent studies suggest a regulatory role of microRNAs (miRNAs) in host immunity. We assessed whether miRNAs also have a regulatory role in immune response to Tp infection in vitro. Our results showed that miR-101-3p levels were significantly higher in peripheral blood mononuclear cells of patients with primary syphilis and those in the serofast state, while TLR2 levels were higher in syphilitic patients than in healthy controls. In vitro, stimulation of THP-1 cells with Tp increased miR-101-3p expression. Moreover, miR-101-3p reduced expression levels of TLR2 mRNA and protein in THP-1 cells via binding to the 3' untranslated region of TLR2. Likewise, miR-101-3p inhibited production of inflammatory cytokines, including IL-1ß, IL-6, TNF-α, and IL-12, in Tp-stimulated macrophages. IL-1ß and IL-6 mRNA expression levels were reduced by transfection of macrophages with a TLR2-specific small interfering RNA. Conversely, overexpression of TLR2 up-regulated cytokines expression. Patients with secondary syphilis exhibited the highest levels of plasma IL-6, which were negatively correlated with miR-101-3p. In conclusion, Tp infection up-regulates miR-101-3p expression, which in turn inhibits the TLR2 signaling pathway, leading to reduced cytokines production.

15.
Eur Phys J E Soft Matter ; 43(1): 3, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31953642

RESUMO

Turbulent wind patterns over a two-dimensional isolated downsized barchan dune under the influence of sinusoidal inflow with different amplitudes and periods are simulated. The evolution rules of wind velocity over time at different positions are revealed. The flow reattachment distance and turbulence intensity distribution are also compared. The results show that wind velocities at different positions of the dune whose similar evolvement process of going from short-term fast adjustment transition to long-term stable sinusoidal fluctuation, can be reasonably estimated by the present simulation. It is found that, for the leeward toe of a dune with complex reversed flow, the balance position value of the sinusoidal wind velocity fluctuation is no longer close to the value of the steady wind velocity but shows a velocity deviation of about 0.40m/s. The flow reattachment distances under different unsteady inflows ultimately show a sinusoidal fluctuation with time, and their values are all larger than that of the steady flow. These synthetically predict that the unsteady flow has a stronger shaping effect on the leeward side of the dune body by enhancing sand transport. In addition, the predicted distribution comparison between unsteady wind velocity and turbulence intensity indicates that the unsteady wind velocity has a dominant effect on the turbulence intensity.

16.
J Environ Sci (China) ; 89: 156-166, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31892388

RESUMO

Different natural sphalerites have a range of photocatalytic properties that can potentially be exploited for environmental remediation purposes. To develop value in the exploitation of sphalerite, samples were collected from 19 ore deposits in China and characterized for their mineralogical and photocatalytic properties. X-ray diffraction (XRD) and electron probe micro analysis (EPMA) measurements indicated that all the natural sphalerites from various localities crystallized in cubic phases with various chemical compositions. The substitution of Fe for Zn ranged from 0.235% to 14.826% by weight, Mn from 0.004% to 4.868%, Cu from 0.009% to 5.529% and Cd from 0.133% to 1.576%. As Fe became more abundant, the color of natural sphalerite darkened, becoming almost black; and higher Fe content was associated with stronger visible light absorption. Photoluminescence spectra showed emission mainly related to S-vacancies and progressively decreasing fluorescence intensity with increasing Fe content. Tests of the photocatalytic degradation of methyl orange indicated that the sample with the highest Cd content but moderate Fe content had the highest photocatalytic activity. Specifically, the degradation of Methyl Orange (30 mg/L) attained 82.11% efficiency under visible light irradiation for 4 hr of natural sphalerite with 4.262% Fe and 1.576% Cd. Overall, the Fe content in sphalerite was found to contribute to the visible light absorption ability and the recombination rate of photo-generated electrons and holes, while substitution by Cd was observed to have a greater effect on the photocatalytic properties. These findings provide a scientific basis for the profitable utilization of base metal resources like sphalerite.

17.
Biomater Sci ; 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31970339

RESUMO

The unique conformation transition from a triple helix to single coils for the triple helical ß-d-glucans has paved the way to fabricate various functional nanocomposites through the denaturing-renaturing process. This study firstly reports a novel kind of naturally derived supramolecular polymer micelle consisting of single-stranded chains of curdlan (CUR) and ß-CDs. It is proposed that ß-CDs as the host molecules were threaded onto single ß-glucan chains (denatured triplex CUR) via the host-guest interaction, thereby forming supramolecular micelles. The results from the 1H NMR, FT-IR, XRD and 2D 1H NOESY NMR studies confirmed the formation of the inclusion complex and the existence of the core-shell structure of the supramolecular assembly. TEM images and DLS revealed that the self-organized micelles displayed a regular spherical shape with an average diameter of ∼27 nm. Furthermore, the hydrophobic anticancer drug camptothecin (CPT) was selected as a model drug and successfully encapsulated into the CUR/ß-CD micelles. The drug-loaded micelles exhibited a steady sustained-release pattern regardless of the environmental pH. The flow cytometry and confocal laser scanning microscopy measurements confirmed that the CPT-loaded micelles could be well internalized into HepG 2 cells and continuously release the drug molecules inside the tumor cells. Meanwhile, the in vivo experiments demonstrated that CPT-loaded micelles could effectively inhibit tumor growth in comparison to free drugs. This concept will give a favorable platform to construct intelligent drug delivery systems for potential use.

18.
Phytochemistry ; 171: 112237, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31901475

RESUMO

Four undescribed alkaloids, namely collacyclumines A-D, along with a known analogue, agrocybenine, were isolated from the endophytic fungus Colletotrichum salsolae SCSIO 41021 derived from the mangrove plant Kandelia candel (L.) Druce. Collacyclumine A represents the first case of dimeric pyrrolidine alkaloid in nature. The structures of these compounds were elucidated by a combination of NMR spectra, HRESIMS data, and X-ray diffraction experiment. A proposed biosynthetic pathway of these isolated compounds were also discussed. None of compounds showed cytotoxic effects against ten cell lines.

19.
Chin Med J (Engl) ; 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31977557

RESUMO

BACKGROUND: The platelet to lymphocyte ratio (PLR) has recently emerged as a potential inflammatory biomarker and has been shown to be significantly associated with atherosclerotic coronary artery disease (CAD). Therefore, we aimed to explore the association of PLR with in-hospital major adverse cardiovascular events (MACEs) and the severity of CAD assessed by the Gensini score (GS) in patients with acute myocardial infarction (AMI) undergoing coronary angiography. METHODS: A total of 502 patients with AMI consecutively treated at the Affiliated Hospital of Qingdao University (Qingdao, China) and underwent coronary angiography from August 2017 to December 2018 were recruited in this study. The demographic, clinical, angiographic characteristics, and laboratory parameters were collected. According to the presence of in-hospital MACEs, the included patients were divided into the MACE group (n = 81) and the non-MACE group (n = 421). Further, according to tertiles of the GS, the patients were classified into three groups: the low GS group (GS ≤ 32 points, n = 173), medium GS group (32 points < GS ≤ 60 points, n = 169), and high GS group (60 points < GS ≤ 180 points, n = 160). The main statistical methods included Chi-squared test, non-parametric Mann-Whitney U test, Kruskal-Wallis H test, logistic regression, and receiver operating characteristic curves. RESULTS: The PLR in the MACE group was significantly higher than that in the non-MACE group (179.43 [132.84, 239.74] vs. 116.11 [87.98, 145.45], Z = -8.109, P < 0.001). Further, there were significant differences in PLR among the tertiles of GS (110.05 [84.57, 139.06] vs. 119.78 [98.44, 157.98] vs. 140.00 [102.27, 191.83], H = 19.524, P < 0.001). PLR was demonstrated to be an independent risk factor of in-hospital MACEs (odds ratio [OR]: 1.012, 95% confidential interval [CI]: 1.006-1.018, P < 0.001) and severe CAD assessed by the GS (OR: 1.004, 95% CI: 1.002-1.009, P = 0.042). The cutoff value of PLR for predicting the development of in-hospital MACEs was 151.28 with a sensitivity of 66.7% and a specificity of 78.1% (area under the curve [AUC]: 0.786, 95% CI: 0.730-0.842, P < 0.001), and a PLR of 139.31 was also identified to be an effective cutoff point for detecting a high GS (>60 points) with a sensitivity of 49.4% and a specificity of 69.6% (AUC: 0.611, 95% CI: 0.556-0.666, P < 0.001). CONCLUSIONS: PLR as a novel inflammatory marker is significantly and independently associated with the occurrence of in-hospital MACEs and the severity of CAD assessed by the GS in patients with AMI. As an easily available and inexpensive inflammatory indicator, PLR could be widely used as an efficient inflammatory biomarker for identifying high-risk patients and for individualizing targeted therapy to improve the prognosis of AMI.

20.
Nat Prod Res ; : 1-8, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31984766

RESUMO

The present work reports the bioassay-guided isolation of four bioactive fatty acid derivatives involving a new butenolide, namely sinulolide I (1) together with three known metabolites (2-4) from the deep-sea sediment derived fungus Aspergillus terreus SCSIO 41202. The chemical structure of compound 1 was elucidated based on extensive spectroscopic methods (1D/2D NMR and HR-ESI-MS), optical rotation and circular dichroism analyses, while the structures of the known compounds (2-4) were established by comparison of NMR spectral data with those reported in literature. All of these four compounds (1-4) exhibited significant antifungal activity against citrus postharvest pathogen Penicillium italicum (MICs around 0.031-0.125 mg/mL).

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