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1.
Cancer Nurs ; 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32404584

RESUMO

BACKGROUND: Adult acute leukemia (AL) patients who receive chemotherapy usually experience multiple symptoms during the treatment course. The symptom clusters (SCs) as well as subsets of concurrent symptoms in AL patients have not yet been demonstrated. OBJECTIVE: To investigate the SCs of adult AL patients who were receiving chemotherapy and to determine their correlations with functional performance. METHODS: A total of 132 hospitalized adult AL patients were included in this study. A cross-sectional survey aimed to examine symptoms and functional performance was conducted. The patients' symptoms were assessed using the Chinese version of the Condensed Memorial Symptom Assessment Scale, and functional performance was evaluated through activities of daily living and quality of life. RESULTS: We identified 4 SCs in adult AL patients: psychological SC, pain-fatigue-sleep SC, dry mouth-constipation SC, and nutrition-impaired SC. The psychological SC was the most common and most distressing SC. The different SCs were each differentially correlated with patient characteristics. The distress of the psychological SC, pain-fatigue-sleep SC, and nutrition-impaired SC was adversely correlated with functional performance. CONCLUSIONS: Adult AL patients undergoing chemotherapy experience multiple symptoms that can be further categorized into 4 SCs. The distress from some SCs is negatively associated with patients' functional performance. IMPLICATIONS FOR PRACTICE: Symptom burden remains a major problem for adult AL patients undergoing chemotherapy. Identifying SCs of AL patients should be the basis for accurate and cost-effective interventions. Personalized SC management may improve the functional performance and healthcare quality of adult AL patients.

2.
Bioresour Technol ; 310: 123433, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32361199

RESUMO

The performance of co-digestion of food waste (FW) and sewage sludge (sludge) by a thermophilic anaerobic membrane bioreactor (ThAnMBR) was firstly investigated. The long-term stable operation showed the feasibility of the utilization of ThAnMBR for mono- and co-digestion of FW and sludge at a high solid condition. Good permeate quality was obtained at all sludge ratios while the addition of sludge restricted the methane generation. For a sludge substitution with a 25% TS-based substrate, the biogas yield of 0.812 L/g-VSfed was at 91% and 158% that of the mono-digestion of FW and sludge, respectively. Membrane performance indicated that the ThAnMBR operated stably at a high flux of 5 LMH under the high solid (~27 g/L) condition. Furthermore, membrane filtration with a 0.1 µm pore size of hollow fiber not only completely removed suspended solids but also rejected about 70% of soluble COD, 80% of soluble carbohydrates and 17% of soluble proteins.


Assuntos
Eliminação de Resíduos , Esgotos , Anaerobiose , Reatores Biológicos , Alimentos , Metano
3.
Lasers Surg Med ; 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32394475

RESUMO

BACKGROUND AND OBJECTIVES: We have developed a novel anti-vascular technique, termed photo-mediated ultrasound therapy (PUT), which utilizes nanosecond duration laser pulses synchronized with ultrasound bursts to remove the microvasculature through cavitation. The objective of the current study is to explore the potential of PUT in removing subcutaneous microvessels. STUDY DESIGN/MATERIALS AND METHODS: The auricular blood vessels of two New Zealand white rabbits were treated by PUT with a peak negative ultrasound pressure of 0.45 MPa at 0.5 MHz, and a laser fluence of 0.056 J/cm2 at 1064 nm for 10 minutes. Blood perfusion in the treated area was measured by a commercial laser speckle imaging (LSI) system before and immediately after treatment, as well as at 1 hour, 3 days, 2 weeks, and 4 weeks post-treatment. Perfusion rates of 38 individual vessels from four rabbit ears were tracked during this time period for longitudinal assessment. RESULTS: The measured perfusion rates of the vessels in the treated areas, as quantified by the relative change in perfusion rate, showed a statistically significant decrease for all time points post-treatment (P < 0.001). The mean decrease in perfusion is 50.79% immediately after treatment and is 32.14% at 4 weeks post-treatment. Immediately after treatment, the perfusion rate decreased rapidly. Following this, there was a partial recovery in perfusion rate up to 3 days post-treatment, followed by a plateau in the perfusion from 3 days to 4 weeks. CONCLUSIONS: This study demonstrated that a single PUT treatment could significantly reduce blood perfusion by 32.14% in the skin for up to 4 weeks. With unique advantages such as low laser fluence as compared with photothermolysis and agent-free treatment as compared with photodynamic therapy, PUT holds the potential to be developed into a new tool for the treatment of cutaneous vascular lesions. Lasers Surg. Med. © 2020 Wiley Periodicals, LLC.

4.
PLoS Pathog ; 16(4): e1008520, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32343745

RESUMO

To confirm the relationship between sex and the progression of Coronavirus Disease-19 (COVID-19), and its potential mechanism, among severe patients. For this retrospective study, we included 168 consecutive severe patients with pathogen-confirmed COVID-19 who were hospitalized between January 16th and February 4th, 2020, at Tongji Hospital in Wuhan, China. Clinical characteristics, laboratory parameters, and outcomes were compared and analyzed between males and females. In the present study, we analyzed 168 severe patients with COVID-19, including 86 males and 82 females, and 48 patients (28.6%) were diagnosed as critically ill. Of 86 male patients, 12.8% (11/86) died and 75.6% (65/86) were discharged; of 82 female patients, 7.3% (6/82) died and 86.6% (71/82) were discharged. Eleven laboratory parameters showed significant differences between male and female patients, and six of them were higher during the whole clinical course in patients who died than in patients who were discharged. In adjusted logistic regression analysis, males with comorbidities presented a higher risk of being critically ill than males without comorbidities (OR = 3.824, 95% CI = 1.279-11.435). However, this association attenuated to null in female patients (OR = 2.992, 95% CI = 0.937-9.558). A similar sex-specific trend was observed in the relation between age and critically ill conditions. We highlighted sex-specific differences in clinical characteristics and prognosis. Male patients appeared to be more susceptible to age and comorbidities. Sex is an important biological variable that should be considered in the prevention and treatment of COVID-19.


Assuntos
Betacoronavirus , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/patologia , Pneumonia Viral/mortalidade , Pneumonia Viral/patologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Comorbidade , Progressão da Doença , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Pandemias , Prognóstico , Fatores Sexuais , Adulto Jovem
5.
Sci Total Environ ; 724: 138168, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32247142

RESUMO

Two temperature-phased anaerobic digestion (TPAD) systems (55 °C in the first reactor and 35 °C in the second reactor) with and without recirculation were operated in parallel for the co-digestion of food waste and paper waste. A long-term experiment was carried out for these two systems with the paper waste ratios elevated from 0 to 50%. The removal efficiencies of COD, TS, VS, carbohydrate and protein in the recirculated TPAD system were higher than those of the non-recirculated system. The successful acclimation of thermophilic cellulose-degrading bacteria in the first reactor (RT1), partly due to recirculation, ensured the effective degradation of cellulose when the paper waste ratio was higher than 40%, resulting in the production of large amounts of hydrogen in reactor RT1. In the absence of recirculation, the main substance produced in the first reactor of the non-recirculated system (T1) was lactic acid. This gradually led to over-acidification and a low degradation efficiency and no methane or hydrogen was produced in T1. Recirculation helped to establish a stable bacterial community capable of producing bio-hydrogen in reactor RT1. The relatively low pH of 5.5 in the RT1 inhibited the activity of hydrogenotrophic archaea without consuming hydrogen, facilitating high hydrogen production levels.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32275582

RESUMO

OBJECTIVE: Photo-mediated ultrasound therapy (PUT) is a novel, non-invasive, agent-free, highly selective, and precise anti-vascular technique. PUT removes microvessels through promoting cavitation activity precisely in targeted microvessels by applying synchronized nanosecond laser pulses and ultrasound bursts. The synchronization between laser and ultrasound is critical to the outcome of PUT. METHODS: Through theoretical simulation and experimental study, the effect of synchronization between laser pulses and ultrasound bursts on cavitation activity during PUT is evaluated. RESULTS: By using a theoretical model, we found that cavitation activity was enhanced when laser pulses and ultrasound bursts were synchronized such that the produced photoacoustic wave overlaid the rarefactional phase of the ultrasound wave. This finding was then verified through in vitro studies where cavitation was monitored by using a passive cavitation detector. Furthermore, we demonstrated that the in vivo treatment outcome of PUT in rabbits was directly related to the synchronization between laser and ultrasound. The anti-vascular effect could only be observed when laser and ultrasound were properly synchronized in vivo. CONCLUSION: PUT is more efficient when the laser-induced photoacoustic wave overlays the rarefactional phase of the ultrasonic wave. SIGNIFICANCE: This is a systematic study to investigate the synchronization effect of PUT, which would be significant for further understanding the mechanism and further improving the treatment efficiency of PUT.

7.
J Control Release ; 322: 566-592, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32276006

RESUMO

Stimuli-responsive nano-assemblies are emerging as promising drug delivery systems (DDSs) with spatial and temporal tenability, which can undergo structural transition for controlled drug release upon excitation by either exogenous or endogenous stimuli. Particularly, exogenous stimuli-responsive nano-assemblies based remotely controlled DDSs, have received much attention due to their accuracy and reliability realized by tunable exogenous triggers such as light, magnetic field, or temperature. In this review, we will briefly introduce the current state-of-the-art technologies of nano-assembly synthesis and summarize the recent advances in remotely controlled nano-assembly-based DDSs activated by different exogenous stimuli or endogenous/exogenous dual-stimuli. Furthermore, the pioneering progress in bio-cleanable stimuli-responsive nano-assemblies that holds great relevance to clinical translation will be described. Finally, we will conclude with our perspectives on current issues and future development of this field. The objective of this review is to outline current advances of nano-assemblies as remotely controlled DDSs, in hopes of accelerating the future development of intelligent nanomedicines.

8.
Biomed Res Int ; 2020: 9358290, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32309443

RESUMO

Background: Dysregulations of AQP7 and AQP9 were found to be related to lipid metabolism abnormality, which had been proven to be one of the mechanisms of stroke. However, limited epidemiological studies explore the associations between AQP7 and AQP9 and the risk of stroke among patients with hypertension in China. Aims: We aimed to investigate the associations between genetic variants in AQP7 and AQP9 and the risk of stroke among patients with hypertension, as well as to explore gene-gene and gene-environment interactions. Methods: Baseline blood samples were drawn from 211 cases with stroke and 633 matched controls. Genomic DNA was extracted by a commercially available kit. Genotyping of 5 single nucleotide polymorphisms (SNPs) in AQP7 (rs2989924, rs3758269, and rs2542743) and AQP9 (rs57139208, rs16939881) was performed by the polymerase chain reaction assay with TaqMan probes. Results: Participants with the rs2989924 GG genotype were found to be with a 1.74-fold increased risk of stroke compared to those with the AA+AG genotype, and this association remained significant after adjustment for potential confounders (odds ratio (OR): 1.74, 95% confidence interval (CI): 1.23-2.46). The SNP rs3758269 CC+TT genotype was found to be with a 33% decreased risk of stroke after multivariate adjustment (OR: 0.67, 95% CI: 0.45-0.99) compared to the rs3758269 CC genotype. The significantly increased risk of stroke was prominent among males, patients aged 60 or above, and participants who were overweight and with a harbored genetic variant in SNP rs2989924. After adjusting potential confounders, the SNP rs3758269 CT+TT genotype was found to be significantly associated with a decreased risk of stroke compared to the CC genotype among participants younger than 60 years old or overweight. No statistically significant associations were observed between genotypes of rs2542743, rs57139208, or rs16939881 with the risk of stroke. Neither interactions nor linkage disequilibrium had been observed in this study. Conclusions: This study suggests that SNPs rs2989924 and rs3758269 are associated with the risk of stroke among patients with hypertension, while there were no statistically significant associations between rs2542743, rs57139208, and rs16939881 and the risk of stroke being observed.

9.
Nanoscale ; 12(15): 8040-8064, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32239038

RESUMO

As the complications of atherosclerosis such as myocardial infarction and stroke are still one of the leading causes of mortality worldwide, the development of new diagnostic tools for the early detection of plaque instability and thrombosis is urgently needed. Advanced molecular imaging probes based on functional nanomaterials in combination with cutting edge imaging techniques are now paving the way for novel and unique approaches to monitor the inflammatory progress in atherosclerosis. This review focuses on the development of various molecular probes for the diagnosis of plaques and thrombosis in atherosclerosis, along with perspectives of their diagnostic applications in cardiovascular diseases. Specifically, we summarize the biological targets that can be used for atherosclerosis and thrombosis imaging. Then we describe the emerging molecular imaging techniques based on the utilization of engineered nanoprobes together with their challenges in clinical translation.

10.
Behav Neurosci ; 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32297752

RESUMO

Although the activity from the dentate gyrus is known to have strong connections with other hippocampal layers, the functionality of these connections, that is, the degree to which it drives activity in the downstream regions of the hippocampus, is not well understood. This question is particularly relevant for mesoscale localfield potential (LFP) rhythms such as gamma oscillations. Following the hypothesis that fundamental features of the LFP are consistent with turbulent dynamics, we investigate the crosslayer relationship between the CA1 layers and the dentate gyrus as a function of running speed. In agreement with previous studies, same-layer spectral and bispectral analyses show that increasing input (rat speed) results in an increase of power and nonlinearity (phase coupling) between theta and gamma. The effectiveness of the connection between the 2 regions is investigated using cross-bicoherence analysis. Based on the turbulence interpretation of the evolution of spectra and bispectra as a function of the power input rate, we propose a measure for estimating the strength of the cross-frequency, cross-layer nonlinear forcing, that compares the magnitude of bicoherence (same-layer) and cross-bicoherence (cross-layer). Our results suggest that at moderate speeds gamma in CA1 is mainly driven by local theta, while the coupling of the CA1 gamma to the dentate-gyrus gamma becomes significant. Overall, these data are consistent with the hypothesis of theta-to-gamma energy cascade model for the organization of hippocampal LFP, with theta playing the role of a global pacemaker across the entire hippocampus while gamma is a local oscillation generated by through local anatomical connections. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

11.
BMC Pregnancy Childbirth ; 20(1): 198, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32252676

RESUMO

BACKGROUND: Gestational diabetes mellitus (GDM) is now a global health problem. Poor blood glucose control during pregnancy may lead to maternal and neonatal/foetal complications. Recently, the development of information and communication technology has resulted in new technical support for the clinical care of GDM. Telemedicine is defined as health services and medical activities provided by healthcare professionals through remote communication technologies. This study aimed to update the systematic review of the effectiveness of telemedicine interventions on glycaemic control and pregnancy outcomes in pregnant women with GDM. METHODS: We searched the Web of Science, PubMed, Scopus, Cochrane Central Register of Controlled Trials, Chinese National Knowledge Infrastructure, Wan-fang Database, China Biology Medicine and VIP Database for randomized controlled trials (RCTs) related to the effectiveness of telemedicine interventions for GDM from database inception to July 31st, 2019. Languages were limited to English and Chinese. Literature screening, data extraction and assessment of the risk of bias were completed independently by two reviewers. Meta-analysis and trial sequential analysis were conducted in Stata 14.0 and TSA v0.9.5.10 beta, respectively. RESULTS: A total of 32 RCTs were identified, with a total of 5108 patients. The meta-analysis showed that telemedicine group had significant improvements in controlling glycated haemoglobin (HbA1c) [mean difference (MD) = - 0.70, P < 0.01], fasting blood glucose (FBG) (MD = -0.52, P < 0.01) and 2-h postprandial blood glucose (2hBG) (MD = -1.03, P = 0.01) compared to the corresponding parameters in the standard care group. In the telemedicine group, lower incidences of caesarean section [relative risk (RR) = 0.82, P = 0.02], neonatal hypoglycaemia (RR = 0.67, P < 0.01), premature rupture of membranes (RR = 0.61, P < 0.01), macrosomia (RR = 0.49, P < 0.01), pregnancy-induced hypertension or preeclampsia (RR = 0.48, P < 0.01), preterm birth (RR = 0.27, P < 0.01), neonatal asphyxia (RR = 0.17, P < 0.01), and polyhydramnios (RR = 0.16, P < 0.01) were found. The trial sequential analyses conclusively demonstrated that the meta-analytic results of the change in HbA1c, the change in 2hBG, the change in FBG, the incidence rates of caesarean section, pregnancy-induced hypertension or preeclampsia, premature rupture of membranes, premature birth, neonatal asphyxia, and polyhydramnios were stable. CONCLUSIONS: Compared to standard care, telemedicine interventions can decrease the glycaemic levels of patients with GDM more effectively and reduce the risk of maternal and neonatal/foetal complications.

12.
Pharmacol Res ; 157: 104824, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32344049

RESUMO

In recent years, the interaction between the bioactive ingredients of traditional Chinese medicine (TCM) and gut microbiota has been a focus of many studies. When TCM enters the digestive tract, some bioactive ingredients are not absorbed into the gut well thus leading to low bioavailability. Ingredients of TCM are metabolised, or biotransformed by gut microbiota, thereby producing new bioactive molecules, and promote medicine absorption into the circulation. At the same time, the ingredients of TCM effect the composition and structure of gut microbiota, thereby influencing the remote function of diseased organs / tissues through the systemic action of the gut microbiota. In this review, we summarise the gut microbiota-mediated metabolism of flavonoids, alkaloids, terpenoids, saponins, polysaccharides, phenylpropanoids, and organic acids, along with a discussion on the metabolites formed and the biotransformation pathways involving various enzymes. We also highlight the importance of bioactive ingredients of TCM in regulating gut microbiota.

13.
Biomed Res Int ; 2020: 9280841, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32190689

RESUMO

Association of Coagulation factor V (F5) polymorphisms with the occurrence of many types of cancers has been widely reported, but whether it is of prognostic relevance in some cancers remain to be resolved. The RNA-sequencing dataset was downloaded from The Cancer Genome Atlas (TCGA). The potential of F5 genes to predict the survival time of gastric cancer (GC) patients was investigated using univariate and multivariate survival analysis whereas "Kaplan-Meier plotter" (KM-plotter) online tools were employed to validate the outcomes. TCGA data revealed that F5 mRNA levels were significantly upregulated in gastric cancer samples. Survival analysis confirmed that high levels of F5 mRNA correlated with short overall survival (OS) in gastric cancer patients, and the area under the curve (AUC) values of 1-, 2-, and 5-year OS rate were 0.554, 0.593, and 0.603, respectively. Survival analysis by KM-plotter indicated that the high expression of F5 mRNA was significantly associated with a shorter OS compared with the low expression level in all patients with GC, and this was also the case for patients in stage III (hazard ratio (HR) = 1.78, P = 0.017). These findings suggest that the F5 gene is significantly upregulated in GC tumour tissues, and may be a potential prognostic biomarker for GC.

15.
Artigo em Inglês | MEDLINE | ID: mdl-32128893

RESUMO

BACKGROUND AND AIM: Chronic inflammation links closely to insulin resistance and lipid metabolism in nonalcoholic fatty liver disease (NAFLD). Macrophage M1 activation plays an important role in the initiation and continuing of pro-inflammatory response of NAFLD. Our study was to investigate whether macrophage M1/M2 polarization switching would affect hepatic inflammation and lipid metabolism through modulation of peroxisome proliferator-activated receptor-gamma (PPAR-γ) activity in vivo and in vitro. METHODS: RAW264.7 macrophages were treated with different fatty acids, and cell culture supernatants were collected to prepare conditioned media (CM). Different co-culture systems between primary hepatocytes and CM from macrophages were established. A PPAR-γ agonist or antagonist was administered to regulate PPAR-γ activity and macrophage polarization. M1/M2 phenotype markers, inflammatory signaling pathway, and lipid-related genes expression were determined. Wild-type C57BL/6 mice were fed a high-fat diet to induce NAFLD and given rosiglitazone to regulate PPAR-γ activity in vivo. RESULTS: Saturated fatty acids induced M1-polarized macrophages while polyunsaturated fatty acids induced M2-polarized macrophages. M1-polarized macrophages significantly promoted lipid synthesis and accumulation in primary hepatocytes through upregulation of a toll-like receptor 4 (TLR4)/NF-κB signaling pathway. The PPAR-γ agonist made lipid-induced M1-polarized macrophages switch to an M2-predominant phenotype, while PPAR-γ antagonist had the opposite effect. Macrophage polarization shifting subsequently affected lipid metabolism in primary hepatocytes. Administration of rosiglitazone improved high-fat diet induced hepatic steatosis and lipid metabolism through reducing hepatic TLR4/NF-κB expression and M1-polarized Kupffer cells. CONCLUSIONS: Lipid-induced macrophage M1 polarization promoted hepatic lipid metabolism. Modulation of PPAR-γ activity could shift macrophage polarization and subsequently affect lipid metabolism. Upregulation of the TLR4/NF-κB signaling pathway is closely linked to dysregulated lipid metabolism in NAFLD.

16.
Inorg Chem ; 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32186867

RESUMO

Most large organic cations in the low-dimensional hybrid halide perovskites deteriorate the photoelectric conversion efficiency of the cells. Integrating electronically active organic components into hybrid metal halides is an effective method to improve their photoelectric properties. In this work, a series of compounds obtained by hybridizing redox-active tetrakis(methylthio)tetrathiafulvalene (TMT-TTF) with bismuth chloride, formulated as [TMT-TTF]4[Bi6Cl22] (1 and 1'), [TMT-TTF]3[Bi4Cl16] (2), [TMT-TTF]2[Bi3Cl13] (3), [TMT-TTF]2[Bi2Cl10] (4), and {[TMT-TTF][Bi2Cl8]}n (5), were crystallographically characterized. These hybrids exhibit changeable oxidation states of the TTF moiety. The radical cation TTF•+ exists in 1 and 1', while a mixed-valence TTF•+/TTF2+ appears in 2 that has never been documented in any compounds and the dication TTF2+ exists in 3-5 that has never been introduced into hybrid organic-inorganic materials. The different charged states of the TTF cations lead to various degrees of connectivity of metal chloride anions, which exert a significant effect on the cation-anion arrangement and result in different supramolecular interactions between TMT-TTF and between cations and anions. The changeable oxidation states of the TTF moiety and varying degrees of metal chloride connectivity provide a good comparison among these hybridized bismuth chlorides. The order of conductivity is 2 > 1 > 1' > 3 ≈ 4 ≫ 5, which results from the synergistic effect of different oxidation states, the packing of TMT-TTF cations, and back charge transfer from the Bi-Cl anion to the TMT-TTF cation. Notably, the electrical conductivity and carrier mobility can be modulated with the fact that compound 2 has the highest performances in the dark, while in light, these properties of 1 and 1' are in turn higher than that of 2. The order of the photocurrent densities is in accordance with the increase of carrier mobility under irradiation of light. This work is the first systematic study of hybrid metal halides with various oxidation states of TTFs and presents a clear structure-property relationship and offers a fresh view on the design of new perovskite materials at the molecular level.

17.
Fitoterapia ; 142: 104529, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32114037

RESUMO

Six new ent-kaurane diterpenoids, isorugosiformins A-F (1-6), were isolated from the aerial parts of Isodon rugosiformis Hand.-Mazz. Hara. Their structures were elucidated by spectroscopic data interpretation, single crystal X-ray diffraction, and quantum chemical calculation of NMR parameters. The absolute configuration of 5 as 6R was the first case in the known 6,7:8,15-diseco-7,20-olide-6,8-cyclo-ent-kaurane diterpenoids.

18.
Molecules ; 25(6)2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32183067

RESUMO

The deposition of aggregated human islet amyloid polypeptide (hIAPP) in the pancreas, that has been associated with ß-cell dysfunction, is one of the common pathological features of patients with type 2 diabetes (T2D). Therefore, hIAPP aggregation inhibitors hold a promising therapeutic schedule for T2D. Chitosan oligosaccharides (COS) have been reported to exhibit a potential antidiabetic effect, but the function of COS on hIAPP amyloid formation remains elusive. Here, we show that COS inhibited the aggregation of hIAPP and disassembled preformed hIAPP fibrils in a dose-dependent manner by thioflavin T fluorescence assay, circular dichroism spectroscopy, and transmission electron microscope. Furthermore, COS protected mouse ß-cells from cytotoxicity of amyloidogenic hIAPP, as well as apoptosis and cycle arrest. There was no direct binding of COS and hIAPP, as revealed by surface plasmon resonance analysis. In addition, both chitin-oligosaccharide and the acetylated monosaccharide of COS and glucosamine had no inhibition effect on hIAPP amyloid formation. It is presumed that, mechanistically, COS regulate hIAPP amyloid formation relating to the positive charge and degree of polymerization. These findings highlight the potential role of COS as inhibitors of hIAPP amyloid formation and provide a new insight into the mechanism of COS against diabetes.

19.
J Environ Sci (China) ; 90: 119-137, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32081309

RESUMO

Based on density functional theory (DFT) and basic structure models, the chemical reactions on the surface of vanadium-titanium based selective catalytic reduction (SCR) denitrification catalysts were summarized. Reasonable structural models (non-periodic and periodic structural models) are the basis of density functional calculations. A periodic structure model was more appropriate to represent the catalyst surface, and its theoretical calculation results were more comparable with the experimental results than a non-periodic model. It is generally believed that the SCR mechanism where NH3 and NO react to produce N2 and H2O follows an Eley-Rideal type mechanism. NH2NO was found to be an important intermediate in the SCR reaction, with multiple production routes. Simultaneously, the effects of H2O, SO2 and metal on SCR catalysts were also summarized.


Assuntos
Modelos Químicos , Titânio , Vanádio , Amônia , Catálise , Teoria da Densidade Funcional
20.
Artigo em Inglês | MEDLINE | ID: mdl-32109507

RESUMO

Epidemiologic studies have shown that sleep disorders are associated with the development of hypertension. The present study investigated dynamic changes in sleep patterns during the development of hypertension across the lifespan in spontaneously hypertensive rats (SHRs) and the neural mechanism that underlies these comorbidities, with a focus on the orexinergic system. Blood pressure in rats was measured using a noninvasive blood pressure tail cuff. Sleep was monitored by electroencephalographic and electromyographic recordings. Immunohistochemistry was used to detect the density and activity of orexinergic neurons in the perifornical nucleus. Hcrt2-SAP (400 or 800 ng) was microinjected in the lateral hypothalamus to lesion orexinergic neurons. Compared with Wistar-Kyoto rats, SHRs exhibited various patterns of sleep disturbances. In SHRs, dynamic changes in hypersomnia in the rats' active phase was not synchronized with the development of hypertension, but hyperarousal in the inactive phase and difficulties in falling asleep were observed concurrently with the development of hypertension. Furthermore, the density and activity of orexinergic neurons in the perifornical nucleus were significantly higher in SHRs than in age-matched Wistar-Kyoto rats. The reduction of orexinergic neurons in the lateral hypothalamus partially ameliorated the development of hypertension and prevented difficulties in falling asleep in SHRs. These results indicate that although the correlation between sleep disturbances and hypertension is very complex, common mechanisms may underlie these comorbidities in SHRs. Overactivity of the orexin system may be one such common mechanism.

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