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1.
Carbohydr Polym ; 235: 115950, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122486

RESUMO

Elution behavior of chitosan was studied using narrow-bore size exclusion chromatography (SEC) columns packed with 8 µm porous particles at different eluent flow rates. Delayed elution of the largest chitosan species from the columns was observed at high flow rates, which was attributable to strong chain deformation rather than chain degradation. In particular, a chromatographic mode transition from SEC to slalom chromatography (SC) was observed for high molar mass chitosan samples with abnormal elution behaviors, which originates from the coil-stretch transition of chitosan chains in elongational flow through the columns. By properly reducing the elongational rate in the columns via tuning the flow rate, particle size and column dimension, the chromatographic mode transition from SEC to SC for chitosan can be effectively suppressed.

2.
Biosens Bioelectron ; 151: 111966, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31999576

RESUMO

Known for their capabilities in automated fluid manipulation, microfluidic devices integrated with pneumatic valves are broadly used for researches in life science and clinical practice. The application is, however, hindered by the high cost and overly complex fabrication procedure. Here, we present an approach for fabricating molds of active fluidic devices using a benchtop 3D printer and a simple 2-step protocol (i.e. 3D printing and polishing). The entire workflow can be completed within 6 h, costing less than US$ 5 to produce all necessary templates for PDMS replica molding, which have smooth surface and round-shaped pneumatic valve structures. Moreover, 3D printing can create unique bespoke on-off objects of a wide range of dimensions. The millimeter- and centimeter-sized features allow examination of large-scale biological samples. Our results demonstrate that the 3D-printed active fluidic device has valve control capacities on par with those made by photolithography. Controlled nutrients and ligands delivery by on-off active valves allows generation of dynamic signals mimicking the ever-changing environmental stimuli, and combinatorial/sequential drug inputs for therapeutic screening on liver tumor spheroid. We believe that the proposed methodology can pave the way for integration of active fluidic systems in research labs, clinical settings and even household appliances for a broad range of application.

3.
Molecules ; 24(24)2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31847478

RESUMO

The problem of an aging society is becoming increasingly acute. Diseases related to aging also come with it. There are some diseases that people can't treat fundamentally. Therefore, people try to find a natural ingredient from natural medicine to treat these diseases and improve the quality of life of the elderly. With the screening of a large number of traditional Chinese medicines, we found that polysaccharides from Rehmannia glutinous (PRG) can prolong the lifespan of Caenorhabditis elegans (C. elegans). Neutral polysaccharide is the main component of PRG. In the present study, we used a C. elegans model to illustrate the stress resistance and lifespan extension effect and mechanism of two kinds of neutral polysaccharide fractions from Rehmannia glutinosa (NPRG), respectively called NPRRP and NPRR. Our data showed that two kinds of neutral polysaccharides fractions could extend the lifespan and delay senescence of wild-type worms. Moreover, the mechanism study revealed that NPRG was able to promote the nuclear localization of DAF-16 resulting in the activation of antioxidant enzymatic systems under oxidative stress. We also observed that NPRG didn't increase the lifespan of mutants with daf-16 portion loss of function, suggesting NPRG prolonging the lifespan partially required the daf-16 gene on the insulin/IGF-1 signaling pathway (IIS). NPRG was found to have no effect on Escherichia coli OP50 (E.coli OP50) growth and pharyngeal pump movement of nematodes, indicating that the anti­aging effect of NPRG is not realized by the caloric restriction. However, mRNA levels of daf-2 were remarkably decreased after NPRG treatment. Thus daf-2 lost its inhibitory effect on the expression of daf-16 and had a continuous stimulation effect on the IIS, then prolonged the life of nematodes. Overall, our results illustrated the potential utilization of NPRG as a functional pharmaceutical ingredient to increase stress resistance and extend the life of C. elegans via the IIS, which could be developed as a natural supplement agent.

4.
Medicine (Baltimore) ; 98(46): e17945, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31725651

RESUMO

The relationship of thyroid function parameters with nonalcoholic steatohepatitis (NASH) in patients with chronic hepatitis B (CHB) remains unknown. Hence, we assessed the impact of thyroid function parameters on NASH in patients with CHB.Consecutive patients with CHB with concurrent nonalcoholic fatty liver disease (NAFLD) were recruited. Liver histology and baseline examinations were carried out in each patient. The associated risk factors for NASH were evaluated.A total of 361 patients with CHB with biopsy-proven NAFLD were included. There was a significant difference in the serum thyroid-stimulating hormone (TSH) level between patients with NASH and non-NASH (3.24 ±â€Š2.00 vs 2.05 ±â€Š1.35 mIU/L, P < .01). Moreover, the NASH prevalence in patients with euthyroidism was significantly higher than in the subclinical hypothyroidism (SCH) patients (P < .001). In multivariate analyses, higher serum concentration of TSH was significantly correlated with NASH (odds ratio [OR]: 1.69, 95% confidence interval [CI]: 1.24-2.31; P = .001). In particular, patients suffering from SCH had a higher risk of having NASH (OR: 4.28, 95% CI: 1.18-15.53; P = .027).Elevated serum TSH level was the independent predictive factor of incident NASH in patients with CHB. Whether the thyroid function parameters should be integrated into future diagnostic scores predicting advanced diseases requires further study.


Assuntos
Hepatite B Crônica/sangue , Hepatite B Crônica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Tireotropina/sangue , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Fatores de Risco , Testes de Função Tireóidea
5.
Rev Sci Instrum ; 90(11): 114502, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31779371

RESUMO

Optical methods have widely been utilized in high-pressure high-temperature experiments for the past several decades. However, optical investigations using the visible spectrum in large volume press have not been well explored. In this study, we incorporate optical access into a multianvil apparatus (MAA) to perform optical experiments. Furthermore, by acquiring the optical image of the sample under high pressure, we have realized the thickness measurement of the sample and further applied it to the existing ultrasonic measurement. We report the optical method from the aspects of apparatus modification, ruby scale, and the demonstrations of the feasibility of the optical access in the MAA.

6.
Geroscience ; 41(6): 847-860, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31650481

RESUMO

Inhibition of mammalian target of rapamycin complex I (mTORC1) by rapamycin improves cardiac function in both aging and heart failure. While the protective mechanisms are not fully understood in mammals, they are presumably mediated through metabolic regulation and suppression of protein translation by reduced phosphorylation of 4EBP1, a target of mTORC1. Using transverse aortic constriction (TAC) and Gαq overexpression-induced heart failure models, we examined the effect of cardiac-specific heterozygous deletion (het) of Raptor, a component of mTORC1, and cardiac-specific transgenic overexpression of wild type or phosphorylation site mutant 4EBP1. In wild-type mice with TAC-induced heart failure, quantitative shotgun proteomics revealed decreased abundance of proteins of mitochondrial metabolism and increased abundance of proteins in oxidative stress response, ubiquitin, and other pathways. The Raptor het ameliorated both TAC- and Gαq overexpression-induced heart failure and the associated proteomic remodeling, especially those pathways involved in mitochondrial function, citric acid cycle, and ubiquitination. In contrast, transgenic overexpression of either wild type or mutant 4EBP1 aggravated TAC and Gαq, consistent with reduced adaptive hypertrophy by suppression of protein translation, in parallel with adverse remodeling of left ventricular proteomes. Partial mTORC1 inhibition by Raptor heterozygous deletion ameliorates heart failure and is associated with better preservation of the mitochondrial proteome; however, this effect does not appear to be mediated through suppression of protein translation by increased 4EBP1. Increased activity of 4EBP1 reduced adaptive hypertrophy and aggravated heart failure, suggesting that protein translation is essential for adaptive hypertrophy in pressure overload.

7.
Emerg Microbes Infect ; 8(1): 1501-1510, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31631782

RESUMO

As one of many nonstructural proteins of porcine reproductive and respiratory syndrome virus (PRRSV), nonstructural protein 12 (Nsp12) has received relatively little attention, and its role in virus replication, if any, is essentially unknown. By the application of reverse genetic manipulation of an infectious PRRSV clone, the current study is the first to demonstrate that Nsp12 is a key component of PRRSV replication. In addition, the biochemical properties of Nsp12 were evaluated, revealing that Nsp12 forms dimers when exposed to oxidative conditions. Furthermore, we systemically analyzed the function of Nsp12 in PRRSV RNA synthesis using a strand-specific PCR method. To our surprise, Nsp12 was not found to be involved in minus-strand genomic RNA (-gRNA) synthesis; importantly, our results indicate that Nsp12 is involved in the synthesis of both plus- and minus-strand subgenomic mRNAs (+sgmRNA and -sgmRNA). Finally, we found that the combination of cysteine 35 and cysteine 79 in Nsp12 is required for sgmRNA synthesis. To our knowledge, we are the first to report the biological role of Nsp12 in the PRRSV lifecycle, and we conclude that Nsp12 is involved in the synthesis of both + sgRNA and -sgRNA.


Assuntos
Regulação Viral da Expressão Gênica , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , RNA Mensageiro/genética , RNA Viral/genética , Proteínas não Estruturais Virais/metabolismo , Animais , Fases de Leitura Aberta , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Suínos , Transcrição Genética , Proteínas não Estruturais Virais/genética , Replicação Viral
8.
Biomed Pharmacother ; 120: 109470, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31590124

RESUMO

Fufang Xueshuantong (FXST), a Chinese patent medicine, is composed of Panax notoginseng, Salviae miltiorrhizae, Astragali Radix and Radix Scrophulariae and has been found to prevent diabetic retinopathy. Yes-associated protein (YAP) participates in the pathophysiology of retinal disease and promotes endothelial cell proliferation and angiogenesis. Although it is known that YAP activity is altered by FXST, the role of YAP in mediating the effect of FXST remains unclear. In high glucose-treated retinal vascular endothelial cells (RVECs), FXST significantly reduced cell viability, the number of migrating cells and tube length in the present study. Moreover, FXST decreased the levels of YAP mRNA and protein and inhibited the expression of vascular endothelial growth factor (VEGF). Transfection of sh-YAP into the cells decreased the ability of FXST to modulate cell migration and tube formation. The effect of FXST on VEGF expression was also decreased. Similar results were obtained when the cells were stimulated with a YAP inhibitor in combination with FXST. Thus, FXST is shown to protect high glucose-injured RVECs via YAP-mediated effects.

9.
PLoS One ; 14(8): e0221704, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31437263

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0212648.].

10.
Medicine (Baltimore) ; 98(33): e16848, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31415412

RESUMO

BACKGROUND: The aim of this study was to investigate the expression of tumor necrosis factor alpha (TNF-α) and interleukin-10 (IL-10) in expressed prostatic secretions (EPSs) of patients with chronic prostatitis (CP) and the expression of prostatic exosomal protein (PSEP) in urine, and to evaluate its correlation with the condition. METHODS: Urine samples from 310 patients with CP (101 National Institutes of Health [NIH] II, 112 NIH IIIa, and 97 NIH IIIb, classified according to the US National Institutes of Health) and 110 control group subjects were collected. The samples were tested for PSEP by enzyme-linked immunosorbent assay (ELISA). At the same time, EPSs in 60 patients from 310 patients with CP and 20 control group subjects were collected. The levels of IL-10 and TNF-α in the collected samples that EPS were determined by double antibody sandwich ELISA. SPSS 23.0 statistical software was used for statistical analysis of the measured data. RESULTS: The level of PSEP in patients with CP was significantly higher than that in the control group (P < .001). The levels of TNF-α and IL-10 in the EPS of patients with NIH II and NIH IIIa CP were higher than those of the patients with NIH IIIb and the control group (P < .001). There was a positive correlation between PSEP and IL-10 and TNF-α, while TNF-α and IL-10 were also positively correlated. CONCLUSION: PSEP, TNF-α, and IL-10 may serve as a basis for the classification diagnosis of CP. Their combination can provide more accurate diagnostic information for clinical CP typing.


Assuntos
Exossomos/metabolismo , Interleucina-10/urina , Próstata/metabolismo , Prostatite/urina , Fator de Necrose Tumoral alfa/urina , Adulto , Biomarcadores/urina , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Humanos , Masculino , Pessoa de Meia-Idade , Prostatite/diagnóstico , Curva ROC , Adulto Jovem
11.
Cell Discov ; 5: 30, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31231540

RESUMO

While it is recognized that there are low levels of new cardiomyocyte (CM) formation throughout life, the source of these new CM generates much debate. One hypothesis is that these new CMs arise from the proliferation of existing CMs potentially after dedifferentiation although direct evidence for this is lacking. Here we explore the mechanisms responsible for CM renewal in vivo using multi-reporter transgenic mouse models featuring efficient adult CM (ACM) genetic cell fate mapping and real-time cardiomyocyte lineage and dedifferentiation reporting. Our results demonstrate that non-myocytes (e.g., cardiac progenitor cells) contribute negligibly to new ACM formation at baseline or after cardiac injury. In contrast, we found a significant increase in dedifferentiated, cycling CMs in post-infarct hearts. ACM cell cycling was enhanced within the dedifferentiated CM population. Single-nucleus transcriptomic analysis demonstrated that CMs identified with dedifferentiation reporters had significant down-regulation in gene networks for cardiac hypertrophy, contractile, and electrical function, with shifts in metabolic pathways, but up-regulation in signaling pathways and gene sets for active cell cycle, proliferation, and cell survival. The results demonstrate that dedifferentiation may be an important prerequisite for CM proliferation and explain the limited but measurable cardiac myogenesis seen after myocardial infarction (MI).

12.
Cancer Cell Int ; 19: 159, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31198408

RESUMO

Background: Mutationally activated Ras proteins are closely linked to a wide variety of human cancers. Hence, there has been an intensive search for anti-Ras therapies for cancer treatment. The sole Ras gene, which encodes LET-60, in Caenorhabditis elegans regulates vulval development. While the loss of let-60 function leads to failure of vulva formation, the let-60(n1046gf) allele, which contains a missense mutation mimicking a Ras codon 13 mutation found in human cancers, results in extra vulval tissue, a phenotype named Muv (multiple vulvas). Methods: By taking advantage of the easy-to-score Muv phenotype of let-60(n1046gf), we used a step-by-step screening approach (from crude extract to active fraction to active natural compound) to search for inhibitors of oncogenic Ras. Mutants of other key components in the Ras-mitogen-activated protein kinase (MAPK) pathway were used to identify other candidate targets. Results: The natural compound harmine, isolated from the plant Peganum harmala, was found to suppress the Muv phenotype of let-60(n1046gf). In addition, harmine targets the hyper-activation of the Ras/MAPK pathway specifically caused by overexpression or mutated forms of LET-60/Ras and its immediate downstream molecule LIN-45/Raf. Finally, harmine can be absorbed into the worm body and probably functions in its native form, rather than requiring metabolic activation. Conclusion: In sum, we have revealed for the first time the anti-Ras activity of harmine in a C. elegans model system. Our results revealed the potential anti-cancer mechanism of harmine, which may be useful for the treatment of specific human cancers that are associated with oncogenic Ras mutations.

13.
ACS Nano ; 13(9): 9880-9894, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31149806

RESUMO

A major challenge in myocardial infarction (MI)-related heart failure treatment using microRNA is the efficient and sustainable delivery of miRNAs into myocardium to achieve functional improvement through stimulation of intrinsic myocardial restoration. In this study, we established an in vivo delivery system using polymeric nanoparticles to carry miRNA (miNPs) for localized delivery within a shear-thinning injectable hydrogel. The miNPs triggered proliferation of human embryonic stem cell-derived cardiomyocytes and endothelial cells (hESC-CMs and hESC-ECs) and promoted angiogenesis in hypoxic conditions, showing significantly lower cytotoxicity than Lipofectamine. Furthermore, one injected dose of hydrogel/miNP in MI rats demonstrated significantly improved cardiac functions: increased ejection fraction from 45% to 64%, reduced scar size from 20% to 10%, and doubled capillary density in the border zone compared to the control group at 4 weeks. As such, our results indicate that this injectable hydrogel/miNP composite can deliver miRNA to restore injured myocardium efficiently and safely.

14.
Nanotechnology ; 30(39): 395401, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31216520

RESUMO

The heterogeneous Co and CeO2 co-decorated N-doping carbon nanofibers (Co-CeO2-N-C) were synthesized via the electrospinning technique. As the bifunctional electrocatalyst, Co-CeO2-N-C nanofibers show excellent oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) performance, owing to the higher degree of graphitization of carbon, the N-doping, and the formation of an interface between Co and CeO2. The liquid Zn-air battery based on Co-CeO2-N-C nanofibers displays excellent specific capacities (815.9 mA h g-1 at 5 mA cm-2), higher open circuit voltages (1.47 V), and good cycling stability (113 h). The corresponding flexible solid state Zn-air battery shows excellent cycling stability (11 h), and good flexibility. Our finding suggests that Co-CeO2-N-C nanofibers could serve as a new group of bifunctional electrocatalysts for OER and ORR with excellent performance, and make them promising for use in future electric vehicles, off-grid power sources, and portable electronics.

15.
Biochem Biophys Res Commun ; 516(2): 546-550, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31235259

RESUMO

BACKGROUND: Circular RNAs (circRNAs) are emerging as important regulators in human disease. The expression profile and mechanism of circRNAs in postmenopausal osteoporosis remains largely unknown. Bone morphogenetic protein 2 (BMP2) is known to play important role in inducing osteogenic differentiation. MiR-98 was reported to regulate osteogenic differentiation of human bone mesenchymal stromal cells by targeting BMP2. AIM: We aimed to analyze circRNA expression profiles in osteoporosis and explore the molecular mechanism of circRNA_0016624 and interaction between circRNA_0016624, miR-98 and BMP2 during osteogenic differentiation. METHODS: RNA-seq and bioinformatics analysis was performed in postmenopausal osteoporosis patients to screen for differentially expressed circRNAs. MiRanda and TargetScan were used to detect miR-98 binding sites of circRNA_0016624 and the target relationship was confirmed by dual luciferase assay. Expression level of circRNA_0016624, miR-98 and BMP2 were measured by qRT-PCR or Western blot. ARS staining was used to observe the level of osteogenic differentiation after transfection. RESULTS: There were 387 circRNAs were differentially expressed in osteoporosis (|fold change| > 2 and P-value < 0.01). circRNA_0016624 and BMP2 were down-regulated in osteoporosis. CircRNA_0016624 could sponge miR-98 and regulate miR-98 expression. Overexpression of circRNA_0016624 promoted the expression of BMP2 and prevented osteoporosis. CONCLUSION: circRNA_0016624 could sponge miR-98 and enhance BMP2 expression, thus circRNA_0016624 prevents osteoporosis and may provide a novel therapeutic strategy.

16.
J Asian Nat Prod Res ; : 1-12, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31119952

RESUMO

The effects of coptisine against advanced stage of human pancreatic carcinoma PANC-1 cells was investigated in vitro. Coptisine (25-150 µM) treatment for 48 h caused dose-dependent cell growth inhibition by using CCK-8 assay. Additionally, coptisine was found to inhibit PANC-1 cells metastasis by the wound healing assay. Flow cytometry data indicated that coptisine (25-100 µM) exhibited dose-dependent G1 phase arrest and moderate reduction of S phase. Coptisine was also found to inhibit ERK phosphorylation and total ERK levels. Our research suggested that coptisine would be a potential therapeutic drug for the treatment of pancreatic cancer.

17.
Aliment Pharmacol Ther ; 50(1): 93-102, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31094016

RESUMO

BACKGROUND: Liver stiffness measurement (LSM) by transient elastography is a noninvasive method for the diagnosis of hepatic fibrosis. The impact of hepatic steatosis on LSM remains to be explored. AIM: To determine whether LSM is affected by hepatic steatosis in patients with chronic hepatitis B (CHB). METHODS: Consecutive patients with biopsy-proven CHB were prospectively enrolled. Hepatic steatosis was classified by pathology as none (S0, <5%), mild (S1, 5%-33%), and moderate-severe (S2-3, >33%), and quantitatively by controlled attenuation parameter (CAP) as CAP S0 (≤247 dB/m), CAP S1 (248-267 dB/m) and CAP S2-3 (≥268 dB/m). Liver fibrosis was assessed by METAVIR classification and noninvasively by LSM. RESULTS: The prevalence of non-alcoholic fatty liver disease (n = 223) in CHB patients (n = 593) was 37.6%. Forty-eight belonged to S2-3 and 127 belonged to CAP S2-3. In patients without significant fibrosis (F0-1), the median LSM (kPa) was 7.4 in S2-3 and 7.1 in CAP S2-3, which was significantly higher than that in S0/S1 (P = 0.005) and CAP S0/S1 (P = 0.003). No significant difference was found in significant fibrosis (F2-4). For LSM identifying significant fibrosis (F2-4), the negative predictive value was higher in CHB patients with CAP ≥ 268 compared to those with CAP < 268 (0.81 vs 0.73); the positive predictive value was lower in CAP ≥ 268 than its counterpart (0.65 vs 0.76). CONCLUSIONS: Moderate-severe steatosis increased the LSM value in CHB patients without significant fibrosis. A CAP ≥ 268 did not affect LSM for ruling out, but it slightly affected LSM for ruling in significant fibrosis. TRIAL REGISTRATION: ChiCTR-DDT-13003983.

18.
J Ethnopharmacol ; 240: 111954, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31085225

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Radix trichosanthis (RT) is a popular plant in China to treat diabetes. AIM OF THE STUDY: The aim of this study is to investigate the therapeutic effect of different extracts of RT and explore the underlying mechanism. METHODS: Ethyl acetate extracts of radix trichosanthis (ERT), methanol extracts of radix trichosanthis (MRT) and water extracts of radix trichosanthis (WRT) were prepared. The retinal vascular endothelial cells (RVEC) were stimulated with high glucose or high glucose plus different extracts of RT. Then, cell viability, Transwell assay, tube formation and BrdU assay were measured. In the end, the Hippo and Notch signaling pathways were evaluated to clarify the pharmacological mechanism. RESULTS: The results indicated that ERT exhibited the best efficacy. It significantly inhibited cell viability, blocked cell migration, attenuated tube formation and reduced the ratio of proliferated cells. It also adjusted the Hippo and Notch signaling pathways. CONCLUSIONS: ERT suppressed high glucose-induced injury in REVC by regulating the Hippo and Notch signaling pathways.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais/efeitos dos fármacos , Glucose/toxicidade , Substâncias Protetoras/farmacologia , Acetatos/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/metabolismo , Macaca mulatta , Proteínas Serina-Treonina Quinases/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Retina/citologia , Transdução de Sinais/efeitos dos fármacos , Solventes/química
19.
Front Chem ; 7: 213, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024898

RESUMO

In this review, we summarize recent studies on giant unilamellar vesicles enclosing aqueous polymer solutions of dextran and poly(ethylene glycol) (PEG), highlighting recent results from our groups. Phase separation occurs for these polymer solutions with concentration above a critical value at room temperature. We introduce approaches used for constructing the phase diagram of such aqueous two-phase system by titration, density and gel permeation chromatography measurements of the coexisting phases. The ultralow interfacial tension of the resulting water-water interface is investigated over a broad concentration range close to the critical point. The scaling exponent of the interfacial tension further away from the critical point agrees well with mean field theory, but close to this point, the behavior disagrees with the Ising value of 1.26. The latter discrepancy arises from the molar mass fractionation of dextran between coexisting phases. Upon encapsulation of the PEG-dextran system into giant vesicles followed by osmotic deflation, the vesicle membrane becomes completely or partially wetted by the aqueous phases, which is controlled by the phase behavior of the polymer mixture and the lipid composition. Deflation leads to a reduction of the vesicle volume and generates excess area of the membrane, which can induce interesting transformations of the vesicle morphology such as vesicle budding. More dramatically, the spontaneous formation of many membrane nanotubes protruding into the interior vesicle compartment reveals a substantial asymmetry and spontaneous curvature of the membrane segments in contact with the PEG-rich phase, arising from the asymmetric adsorption of polymer molecules onto the two leaflets of the bilayers. These membrane nanotubes explore the whole PEG-rich phase for the completely wetted membrane but adhere to the liquid-liquid interface as the membrane becomes partially wetted. Quantitative estimates of the spontaneous curvature are obtained by analyzing different aspects of the tubulated vesicles, which reflect the interplay between aqueous phase separation and spontaneous curvature. The underlying mechanism for the curvature generation is provided by the weak adsorption of PEG onto the lipid bilayers, with a small binding affinity of about 1.6 kBT per PEG chain. Our study builds a bridge between nanoscopic membrane shapes and membrane-polymer interactions.

20.
Complement Ther Med ; 43: 208-217, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30935533

RESUMO

OBJECTIVE: The severity of angina pectoris has been recognized. It is believed that Chinese herbal injections have an outstanding clinical effect on this condition. This network meta-analysis was devised to investigate the comparative efficacy of eight Chinese herbal injections (Ciwujia injection, Dazhuhongjingtan injection, Huangqi injection, Shenfu injection, Shengmai injection, Shenmai injection, Shenqi Fuzheng injection, Yiqifumai injection) in the treatment of angina pectoris. METHODS: A literature search was performed in PubMed, Embase, and the Cochrane Library, Chinese Biological Medicine Database, China National Knowledge Infrastructure, Wanfang Database, and Chinese Scientific Journal Database from their inception to June 25, 2018. A pre-designed eligibility criterion was utilized in this network meta-analysis, and a methodological quality analysis was conducted. Data analysis was performed by WinGUGS 1.4.3, Stata 13.0 and TSA software, and the odds ratio or mean difference with the 95% credible interval was reported for symptomatic improvement, electrocardiography improvement, fibrinogen, triglyceride and cholesterol. The ranking probability of interventions in various outcomes was also utilized. RESULTS: A total of 73 randomized controlled trials with 6639 patients were identified. Integrating network meta-analysis results, Shenqi Fuzheng injection plus western medicine therapy and Shenmai injection plus western medicine therapy were shown to be more efficacious than other therapies. In addition, Huangqi injection plus western medicine therapy and Shenmai injection plus western medicine therapy performed well in improving the haemorheology index and serum lipid parameters. CONCLUSIONS: Eligible Chinese herbal injections plus western medicine therapy might have a better impact on angina pectoris patients than western medicine therapy alone. While this study had limitations, the findings should be interpreted with caution. In addition, more high-quality randomized controlled trials with a large sample must be conducted to support this study.


Assuntos
Angina Pectoris/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Teorema de Bayes , China , Humanos , Injeções , Meta-Análise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto
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