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1.
Front Immunol ; 11: 148, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32158445

RESUMO

Inflammation is one of the hallmarks of non-alcoholic steatohepatitis. CD47 is a widely expressed transmembrane protein that signals through inhibitory receptor signal regulatory protein α (SIRPα) to inhibit macrophage activation and phagocytosis. In this study, we sought to investigate the role of CD47 in hepatosteatosis and fibrosis induced by a chronic high-fat diet (HFD), by comparing disease development in wild-type (WT) and CD47KO mice fed HFD for 40 weeks. The HFD induced remarkably more severe hepatic steatosis and fibrosis but less body weight gain and less subcutaneous fat accumulation in CD47KO mice compared to WT mice. Liver tissues from HFD-fed CD47KO mice exhibited enhanced inflammation characterized by increased proinflammatory cytokine production and increased nuclear factor-κB (NF-κB) activation compared to similarly fed WT mice. Although higher expression of apolipoproteins was observed in CD47KO mice compared to WT mice under a low-fat diet (LFD), HFD-fed WT and CD47KO mice showed comparably prominent downregulation of these apolipoprotein genes, suggesting that the marked difference observed in lipid accumulation and hepatosteatosis between these mice cannot be explained by changes in apolipoproteins. Like apolipoproteins, sirtuin 1 (SIRT1) and peroxisome proliferator activated receptor alpha (PPARα), which are involved in regulation of both lipid metabolism and inflammation, were more highly expressed in CD47KO than WT mice under LFD but more severely suppressed in CD47KO than in WT mice under HFD. Taken together, our results indicate that CD47 plays a significant role in the pathogenesis of HFD-induced hepatosteatosis and fibrosis through its role in regulation of inflammation and lipid metabolism.

2.
Ann Palliat Med ; 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32156136

RESUMO

BACKGROUND: This study aimed to assess the relationship between the use of dexmedetomidine and the incidence of acute kidney injury (AKI) in septic shock patients undergoing mechanical ventilation and reveal the potential mechanism. METHODS: Septic shock patients undergoing mechanical ventilation were included. Patients were randomized into two groups including propofol group and dexmedetomidine group. Plasma samples were obtained from veins at 0, 12, 24, 72 and 120 h after receiving mechanical ventilation in ICU. RESULTS: Cohorts with septic shock after mechanical ventilation in ICU had similar baseline and demographic characteristics. Serum creatinine (SCr) and blood urea nitrogen (BUN) was lower in dexmedetomidine group (P<0.05) and also lower renal injury markers were detected in the dexmedetomidine group, compared with propofol group (P<0.05). Dexmedetomidine infusion reduced the TNF-α, IL-1 level in blood samples and maintained the balance of proportion of CD4+ and CD8+ T-lymphocytes. Patients receiving dexmedetomidine were less likely to develop AKI. The median ICU stay was decreased in dexmedetomidine group (P<0.05). Moreover, the case and duration of CRRT was also decreased by using dexmedetomidine (P<0.05). There was no significant difference between the cohorts with respect to the duration of mechanical ventilation. CONCLUSIONS: The use of dexmedetomidine infusion in ICU patients was associated with a decreased incidence of AKI and reduced ICU stay and CRRT performance. The mechanism may be related to antiinflammatory reaction and immunoregulation.

3.
J Cell Commun Signal ; 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32157550

RESUMO

Erlotinib is an oral tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR) pathway. Although our previous study has proved the efficacy of Erlotinib in head and neck squamous cell carcinoma (HNSCC), it has also demonstrated poor clinical response rates and disappointing results in clinical trials for HNSCC to date. In this study, we discovered elevated cell proliferation and invasion ability in erlotinib-resistant HNSCC cells. The contributions of miRNAs within extracellular vesicles (EVs) during the formation of chemoresistance were investigated in this study. Among up-regulated miRNAs in EVs derived from resistant cells, miR-7704, miR-21-5p and miR-3960 showed the most pro-tumorigenic alterations after transfection. Conversely, let-7i-5p, miR-619-5p and miR-30e-3p demonstrated tumor suppressive effects. By performing qRT-PCR and Western blot analysis, we found Vimentin played a pivotal role in modulating erlotinib resistance. Additionally, immune system was highlighted in the GO and KEGG analyses. Transfection of miR-7704, miR-21-5p significantly elevated CTLA-4 and LAG3 mRNA levels. Meanwhile, miR-3960 increased the relative mRNA expression of TIM3 in HNSCC cells. Transfection of let-7i-5p, miR-619-5p and miR-30e-3p decreased these checkpoint factors. To conclude, the present study described the roles of EVs-transmitted miRNAs on erlotinib resistance. Targeting the disregulated immune system could be the effective method to overcome erlotinib-resistance in HNSCC cells.

4.
Sci Rep ; 10(1): 5099, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32198366

RESUMO

An increasing body of evidence has implicated the innate immune system in the causation of acute ST-segment elevation myocardial infarction (STEMI). Innate lymphoid cells (ILCs) are newly identified members of the lymphoid lineage that are important effectors of innate immunity. The role of ILCs in STEMI has not been explored. We characterized the ILCs present in peripheral blood of 176 STEMI patients and 52 controls. Patients were followed up for up to 23 months. Flow cytometry showed that the proportion of total ILCs and ILC1s were significantly increased compared with controls; contrary to ILC1s, the proportion of ILC2s among total ILCs decreased significantly during the acute phase of STEMI. ILC1s percentage was an independent predictor of major adverse cardiovascular events (MACE). On multivariate Cox regression, the 3rd tertile of ILC1s was associated with a higher MACE rate compared with the 1st tertile (hazard ratio: 2.26; 95% confidence interval 1.56-3.27; P = 0.014). RNA-sequencing (RNA-Seq) revealed increased expressions of interferon-γ, tumor necrosis factor-α, vascular cell adhesion molecule 1 (VCAM1), and matrix metallopeptidase 9. Moreover, as active factors secreted by ILC1s, levels of interleukin (IL)-12 and IL-18 were significantly increased in STEMI patients. Increased ILC1s in patients with STEMI was associated with poor outcomes. Our findings suggest that ILC1s may play an important role in STEMI.

5.
Mult Scler Relat Disord ; 42: 102057, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32222694

RESUMO

OBJECTIVE: Recent reports have suggested that seizures may be a component of the clinical presentation in myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated disease. We aimed to conduct a systematic review and meta-analysis to comprehensively evaluate the occurrence of epileptic seizures in the disease. METHODS: We searched PubMed, MEDLINE and EMBASE for studies reporting the occurrence of acute symptomatic seizures in MOG-Ab-associated disease. Fixed or random effects model was used to pool results across studies with a meta-analysis. RESULTS: A total of 14 studies met the inclusion criteria. Overall, acute symptomatic seizures were observed in 20.5% (95% confidence interval [CI] 13.7%-30.7%, I2=60.6%) patients with MOG-Ab-associated disease, and in a similar proportion of children respectively (20.0%; 95% CI 14.3%-27.8%, I2=7.0%). The pooled probability of seizure occurrence in males was 30.1% (95% CI 17.5%-52%, I2=0.0%) while that in females was much lower (12.0%; 95% CI 5.5%-26.4%, I2=0.0%). Furthermore, when we focused on those with acute disseminated encephalomyelitis-like phenotype, 37.3% patients experienced seizures (95% CI 21.0%-66.3%, I2=55.8%). CONCLUSIONS: Our study suggested that epileptic seizures were common in MOG-Ab-associated disease and offered insight into associated factors that contribute to the occurrence of seizures. Future studies with explicit evaluation are required.

6.
Food Chem ; 319: 126564, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32163841

RESUMO

Zanthoxylum armatum DC Prodr. pericarp (ZAP) is an important spice because of its unique odor and taste. ZAP oil was obtained by supercritical carbon dioxide extraction. To characterize potent odorants in ZAP oil, volatiles were isolated by headspace solid-phase microextraction and solvent-assisted flavor evaporation. Gas chromatography-mass spectrometry-olfactometry analyses identified a total of 32 odor-active compounds, and their flavor dilution (FD) factors, ranging from 2 to 4096, were measured by aroma extract dilution analysis. To further determine their contributions to the characteristic odor of ZAP oil, 24 odorants with FD factors ≥8 were quantitated, and their odor activity values (OAVs) were calculated. Sixteen compounds with OAVs ≥1 contributed to the characteristic aroma profile of ZAP oil. Linalool had the highest FD factor, concentration and OAV, and its chiral structure was identified as S-(+)-linalool.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32198676

RESUMO

Simulated microgravity can significantly affect various cell types and multiple systems of the human body, such as cardiovascular system, skeletal muscle system, and immune system, and is known to cause anemia and loss of electrolyte and fluids. Epidermal stem cells (EpSCs) were cultured in a rotary cell culture system (RCCS) bioreactor to simulate microgravity. The metabolites of EpSCs were identified by liquid chromatography-mass spectrometry (LC-MS). Compared with normal gravity (NG) group, a total of 57 different metabolites of EpSCs were identified (P < 0.05, VIP > 1), including lipids and lipid-like molecules (51 molecules), amino acids (5 molecules), nucleosides, nucleotides, and analogues (1 molecule). According to the partial least squares discriminant analysis (PLS-DA) score plot, a VIP > 1 and P < 0.05 were obtained for the 57 different metabolites, of which 23 molecules were significantly downregulated and 34 were significantly upregulated in simulated microgravity (SMG) group. These results showed that SMG has a significant impact on different pathways, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis indicated that multiple pathways were involved, mainly the amino acid metabolism pathway, lipid metabolism pathway, membrane transport pathway, and cell growth and death pathways. Thus, the metabolic profile of EpSCs was changed under SMG. Exploring the metabolic profile of EpSCs would be helpful to further understand the growth characteristics of EpSCs under SMG, which will provide a new approach to explore the metabolomics mechanism of stress injury and repair trauma under SMG.

8.
Cardiovasc Ther ; 2020: 8647837, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32190122

RESUMO

Background: Anemia following acute myocardial infarction (AMI) is associated with poor outcomes. While previous studies in patients with AMI have focused on anemia at admission, we hypothesized that hemoglobin (Hb) decline during hospitalization and lower discharge Hb would be associated with greater long-term mortality in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). Methods: We analyzed records of 983 STEMI patients who were treated with primary PCI. The primary end point was all-cause mortality at 1 year and 2 years. The relationship between discharge Hb levels, decline in Hb levels, bleeding event classification, and all-cause mortality was determined. Results: Overall, 16.4% of patients had bleeding events, which were classified by the Thrombolysis in Myocardial Infarction (TIMI) score as 7% minimal, 8.6% minor, and 0.9% major. No significant gastrointestinal bleed and cerebral hemorrhage occurred in hospitals among these patients. The incidence rate of the 2-year all-cause mortality increased with severity of the bleeding event score (8.78% for no bleeding vs. 11.59% for minimal bleeding vs. 20.24% for minor bleeding vs. 55.56% for major bleeding, P < 0.001). Discharge Hb was significantly associated with 2-year mortality in an unadjusted model (hazard ratio (HR) per 1 g/L decrease in discharge Hb = 1.020, 95% confidence interval (CI): 1.006-1.034, P < 0.001). Discharge Hb was significantly associated with 2-year mortality in an unadjusted model (hazard ratio (HR) per 1 g/L decrease in discharge Hb = 1.020, 95% confidence interval (CI): 1.006-1.034, P < 0.001). Discharge Hb was significantly associated with 2-year mortality in an unadjusted model (hazard ratio (HR) per 1 g/L decrease in discharge Hb = 1.020, 95% confidence interval (CI): 1.006-1.034. Conclusions: In this population of patients hospitalized for STEMI, all-cause mortality increased with lower discharge Hb, and discharge Hb was a significant predictor of mortality risk.

9.
Psychiatry Res Neuroimaging ; 298: 111047, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32114310

RESUMO

Electroacupuncture (EA) is a safe method for treating obesity; however, its underlying neural mechanisms remain unclear. We employed resting-state-functional-magnetic-resonance-imaging (RS-fMRI) and amplitude-of-low-frequency-fluctuation (ALFF) to investigate acute/long-term effects of EA on brain activity and resting-state-functional-connectivity (RSFC) in overweight/obesity subjects who received real/Sham stimulation. For acute effects, 26 and 19 overweight/obesity subjects were included in EA and Sham groups respectively. There were significant time effects on ALFF in the right insula (INS) and left dorsolateral-prefrontal-cortex (DLPFC) due to decreases/increases in INS/DLPFC in both groups. There were weaker positive RSFC between INS and supplementary-motor-area (SMA)/right DLPFC and weaker negative RSFC between INS and precuneus (PCUN); stronger negative RSFC between DLPFC and dorsomedial-prefrontal-cortex (DMPFC) in both groups. For long-term study, body-mass-index (BMI) had significant reduction in EA (n = 17) and Sham (15) groups; EA had higher BMI reduction than in Sham. There were significant time effects on ALFF in right ventrolateral-prefrontal-cortex (VLPFC) due to significant increases in EA group, and stronger positive RSFC between VLPFC and orbitofrontal-cortex and negative RSFC between VLPFC and left thalamus (THA) in both groups after long-term treatment. These findings suggest that changes in resting-activity and RSFC implicated in inhibitory-control, gastric-motility and satiety-control are associated with EA-induced weight-loss.

10.
Neurogastroenterol Motil ; : e13808, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32114712

RESUMO

BACKGROUND: Electroacupuncture (EA) is widely used in various gastrointestinal diseases around the world, including POI. Here, we investigated different therapeutic effects of EA using lower limb and abdomen acupoints. METHODS: Intestinal manipulation was performed in 88 mice, and eight mice underwent a sham operation. Forty mice were randomly divided into model group and four EA groups receiving stimulation at ST36 (2, 10, 30, 100 Hz). The most effective frequency was then used in the following experiments. Forty-eight mice were randomly divided into six groups receiving EA treatment at ST37, ST39, ST25, CV4, CV12, and a non-acupuncture point. Gastrointestinal motility and plasma TNF-α, IL-6 were evaluated in all mice. The local immune response and α-smooth muscle actin (α-SMA) expression were assessed by immunofluorescence, ELISA, and HE staining. RESULTS: ST36 stimulated with 10 or 30 Hz EA significantly increased the gastrointestinal motility and attenuated peripheral inflammation; however, ST36 stimulated with 2 or 100 Hz did not induce any effect. The therapeutic effects on motility and inflammation of 10 Hz EA in the ST36 group were similar in the ST36, ST37, ST39, or CV4 groups, but when applied to ST25, CV12 or non-acupoint had no significant differences. EA at ST36, ST37, ST39, or CV4 significantly inhibited local MPO activity, immune cells infiltration, and increased α-SMA. CONCLUSIONS: EA at lower limb and abdomen acupoints with the same stimulation parameters had different therapeutic effects on postoperative dysmotility and inflammation. Furthermore, EA protected SMC to improve gastrointestinal transit by reducing local inflammation in the intestinal musculature in POI.

11.
Phys Chem Chem Phys ; 22(9): 5024-5032, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32073087

RESUMO

Several gas-phase spectroscopic investigations have focused on a better understanding of the nature of weak, non-covalent interactions in model systems. However, their characterization and interpretation are still far from being satisfactory. A promising route to fill this gap is offered by strategies in which high-resolution rotational spectroscopy is deeply integrated with state-of-the-art quantum-chemical methodology to accurately determine intermolecular parameters and interaction energies, with the latter interpreted by means of powerful energy decomposition analyses (EDAs). As a proof of concept of this approach, we have selected the adducts formed by n-propylamine (PA) and iso-propylamine (IPA) with water. Among the stable structures computationally predicted, four (out of five) isomers of the PA-water complex and two isomers (trans and gauche) of the IPA-water adduct have been characterized with supersonic jet Fourier transform microwave spectroscopy. Starting from the experimental rotational constants for different isotopic species, computation of the corresponding vibrational corrections allowed a semi-experimental determination of the intermolecular parameters. Different EDAs point out that in all cases a strong O-HN hydrogen bond is the primary interaction. Accurate computations indicate that the length and ramification of the alkyl chain do not significantly affect the water-amine interactions, which - on the contrary - modify the stability order of PA conformers with respect to the isolated systems.

12.
Acupunct Med ; : 964528419900911, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32028783

RESUMO

BACKGROUND: Evidence for treating postprandial distress syndrome with acupuncture is limited. AIM: We aimed to evaluate the feasibility of verum acupuncture versus sham acupuncture in patients with postprandial distress syndrome. METHODS: A total of 42 eligible patients were randomly allocated to either verum acupuncture or sham acupuncture groups in a 1:1 ratio. Each patient received 12 sessions over 4 weeks. The primary outcome was the response rate based on the overall treatment effect (OTE) 4 weeks after randomization. Secondary outcomes included dyspepsia symptom severity and adverse events. RESULTS: In each group, 19 patients (91.5%) completed the study. Thirteen patients receiving verum acupuncture and seven patients receiving sham acupuncture were classified as responders according to OTE (61.9% vs 33.3%; rate difference 28.6%; p = 0.06). Dyspepsia symptom severity at the end of treatment also differed significantly between verum acupuncture and sham acupuncture groups (5.9 units vs 3.7 units; between-group difference 2.2 (95% CI, 0.2-4.2); p = 0.04). No serious adverse events occurred. CONCLUSION: Four weeks of acupuncture may represent a potential treatment for postprandial distress syndrome. The treatment protocol and outcome measures used in this trial were feasible. Since this was a pilot study, the efficacy of acupuncture still needs to be determined by a larger, adequately powered trial.

13.
Water Res ; 173: 115581, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32058153

RESUMO

This study provided an overview of established and emerging nanomaterial (NM)-enabled processes and devices for water disinfection for both centralized and decentralized systems. In addition to a discussion of major disinfection mechanisms, data on disinfection performance (shortest contact time for complete disinfection) and energy efficiency (electrical energy per order; EEO) were collected enabling assessments firstly for disinfection processes and then for disinfection devices. The NM-enabled electro-based disinfection process gained the highest disinfection efficiency with the lowest energy consumption compared with physical-based, peroxy-based, and photo-based disinfection processes owing to the unique disinfection mechanism and the direct mean of translating energy input to microbes. Among the established disinfection devices (e.g., the stirred, the plug-flow, and the flow-through reactor), the flow-through reactor with mesh/membrane or 3-dimensional porous electrodes showed the highest disinfection performance and energy efficiency attributed to its highest mass transfer efficiency. Additionally, we also summarized recent knowledge about current and potential NMs separation and recovery methods as well as electrode strengthening and optimization strategies. Magnetic separation and robust immobilization (anchoring and coating) are feasible strategies to prompt the practical application of NM-enabled disinfection devices. Magnetic separation effectively solved the problem for the separation of evenly distributed particle-sized NMs from microbial solution and robust immobilization increased the stability of NM-modified electrodes and prevented these electrodes from degradation by hydraulic detachment and/or electrochemical dissolution. Furthermore, the study of computational fluid dynamics (CFD) was capable of simulating NM-enabled devices, which showed great potential for system optimization and reactor expansion. In this overview, we stressed the need to concern not only the treatment performance and energy efficiency of NM-enabled disinfection processes and devices but also the overall feasibility of system construction and operation for practical application.

14.
Circulation ; 141(7): 530-539, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32065775

RESUMO

BACKGROUND: Despite improvements in diagnostic and therapeutic interventions to combat cardiovascular disease (CVD) in recent decades, there are significant ongoing access gaps and sex disparities in prevention that have not been adequately quantified in China. METHODS: A representative, cross-sectional, community-based survey of adults (aged ≥45 years) was conducted in 7 geographic regions of China between 2014 and 2016. Logistic regression models were used to determine sex differences in primary and secondary CVD prevention, and any interaction by age, education level, and area of residence. Data are presented as adjusted odds ratios (ORs) and 95% CIs. RESULTS: Of 47 841 participants (61.3% women), 5454 (57.2% women) had established CVD and 9532 (70.5% women) had a high estimated 10-year CVD risk (≥10%). Only 48.5% and 48.6% of women and 39.3% and 59.8% of men were on any kind of blood pressure (BP)-lowering medication, lipid-lowering medication, or antiplatelet therapy for primary and secondary prevention, respectively. Women with established CVD were significantly less likely than men to receive BP-lowering medications (OR, 0.79 [95% CI, 0.65-0.95]), lipid-lowering medications (OR, 0.69 [95% CI, 0.56-0.84]), antiplatelets (OR, 0.53 [95% CI, 0.45-0.62]), or any CVD prevention medication (OR, 0.62 [95% CI, 0.52-0.73]). Women with established CVD, however, had better BP control (OR, 1.31 [95% CI, 1.14-1.50]) but less well-controlled low-density lipoprotein cholesterol (OR, 0.66 [95% CI, 0.57-0.76]), and were less likely to smoke (OR, 13.89 [95% CI, 11.24-17.15]) and achieve physical activity targets (OR, 1.92 [95% CI, 1.61-2.29]). Conversely, women with high CVD risk were less likely than men to have their BP, low-density lipoprotein cholesterol, and bodyweight controlled (OR, 0.46 [95% CI, 0.38-0.55]; OR, 0.60 [95% CI, 0.52-0.69]; OR, 0.55 [95% CI, 0.48-0.63], respectively), despite a higher use of BP-lowering medications (OR, 1.21 [95% CI, 1.01-1.45]). Younger patients (<65 years) with established CVD were less likely to be taking CVD preventive medications, but there were no sex differences by area of residence or education level. CONCLUSIONS: Large and variable gaps in primary and secondary CVD prevention exist in China, particularly for women. Effective CVD prevention requires an improved overall nationwide strategy and a special emphasis on women with established CVD, who have the greatest disparity and the most to benefit.

15.
Front Med ; 14(1): 51-59, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31938981

RESUMO

The aim of this study was to characterize rpoC gene mutations in Mycobacterium tuberculosis (MTB) and investigate the factors associated with rpoC mutations and the relation between rpoC mutations and tuberculosis (TB) transmission. A total of 245 MTB clinical isolates from patients with TB in six provinces and two municipalities in China were characterized based on gene mutations through DNA sequencing of rpoC and rpoB genes, phenotyping via standard drug susceptibility testing, and genotypic profiling by mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing. Approximately 36.4% of the rifampin-resistant isolates harbored nonsynonymous mutations in the rpoC gene. Twenty-nine nonsynonymous single mutations and three double mutations were identified. The rpoC mutations at locus 483 (11.3%) were predominant, and the mutations at V483G, W484G, I491V, L516P, L566R, N698K, and A788E accounted for 54.5% of the total detected mutations. Fifteen new mutations in the rpoC gene were identified. Rifampin resistance and rpoB mutations at locus 531 were significantly associated with rpoC mutations. MIRU-VNTR genotype results indicated that 18.4% of the studied isolates were clustered, and the rpoC mutations were not significantly associated with MIRU-VNTR clusters. A large proportion of rpoC mutation was observed in the rifampicin-resistant MTB isolates. However, the findings of this study do not support the association of rpoC mutation with compensated transmissibility.

16.
J Phys Chem A ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31985228

RESUMO

The conformational isomerism of isopropylamine and n-propylamine has been investigated by means of an integrated strategy combining high-level quantum-chemical calculations and high-resolution rotational spectroscopy. The equilibrium structures (and thus equilibrium rotational constants) as well as relative energies of all conformers have been computed using the so-called "cheap" composite scheme, which combines the coupled-cluster methodology with second-order Møller-Plesset perturbation theory for extrapolation to the complete basis set. Methods rooted in the density functional theory have been instead employed for computing spectroscopic parameters and for accounting for vibrational effects. Guided by quantum-chemical predictions, the rotational spectra of isopropylamine and n-propylamine have been investigated between 2 and 400 GHz with Fourier transform microwave and frequency-modulation millimeter/submillimeter spectrometers. Spectral assignments confirmed the presence of several conformers with comparable stability and pointed out possible Coriolis resonance effects between some of them.

17.
Liver Int ; 40(2): 298-307, 2020 Feb.
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 six 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: Favourable 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.

18.
J Neural Eng ; 17(1): 016064, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-31791027

RESUMO

OBJECTIVE: Neuromuscular electrical stimulation can help activate muscles of individuals with neurological disorders. However, conventional electrical stimulation targets distal branches of motor axons, and activates muscles non-physiologically. For example, stimulation at the muscle belly activates muscles in a highly synchronized manner. Accordingly, we investigated whether the muscle activation pattern was more asynchronized through transcutaneous stimulation near the cervical spinal cord (tsCSC). APPROACH: A stimulation array was placed on the posterior side near the cervical spinal cord, to target the arm and hand muscles. Stimulation trains of 10 Hz and 30 Hz were delivered. Electromyogram signals were recorded to quantify the muscle activation patterns. Arm and finger joint kinematics were also recorded using a motion capture system. MAIN RESULTS: After an initial synchronized activation prior to 35 ms after stimulation onset, we observed substantial asynchronized muscle activities with a long latency (>35 ms). The asynchronized activation is also more evident in distal muscles compared with the proximal muscles. In addition, the decreased synchronization level of muscle activities correlated with a reduced fluctuation of joint movement. The highly asynchronized muscle activities indicated an activation of the sensory axons and/or dorsal roots as well as a possible involvement of some spinal-supraspinal circuitry. SIGNIFICANCE: Our tsCSC approach can improve the muscle activation pattern during electrical stimulation with a possible involvement of the spinal and supraspinal pathways, which can facilitate applications on rehabilitation/assistance of individuals with impaired motor function.

20.
Metab Eng ; 58: 82-93, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31302223

RESUMO

PHA, a family of natural biopolymers aiming to replace non-degradable plastics for short-term usages, has been developed to include various structures such as short-chain-length (scl) and medium-chain-length (mcl) monomers as well as their copolymers. However, PHA market has been grown slowly since 1980s due to limited variety with good mechanical properties and the high production cost. Here, we review most updated strategies or approaches including metabolic engineering, synthetic biology and morphology engineering on expanding PHA diversity, reducing production cost and enhancing PHA production. The extremophilic Halomonas spp. are taken as examples to show the feasibility and challenges to develop next generation industrial biotechnology (NGIB) for producing PHA more competitively.

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