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1.
Mol Phylogenet Evol ; 168: 107413, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35031460

RESUMEN

Historical geo-climatic changes have shaped the geographical distributions and genetic diversity of numerous plant taxa in East Asia, which promote species divergence and ultimately speciation. Here, we integrated multiple approaches, including molecular phylogeography, ecological niche modeling, and morphological traits to examine the nucleotide diversity and interspecific divergence within Corylus heterophylla complex (C. heterophylla, C. kweichowensis, and C. yunnanensis). These three sibling taxa harbored similar high levels of nucleotide diversity at the species level. The molecular data (SCNG and cpDNA) unanimously supported the division of C. heterophylla complex into two major clades, with C. yunnanensis diverged earlier from the complex, whereas C. heterophylla and C. kweichowensis could hardly be separated. The split between the two clades (c. 12.89 Ma) coincided with the formation of Sichuan Basin in the middle Miocene, while the divergence among and within the five subclades (YUN1-YUN3, HK1-HK2) occurred from the late Miocene to the Pleistocene. C. heterophylla of northern China experienced glacial contraction and interglacial expansion during the Quaternary, whereas C. kweichowensis and C. yunnanensis of southern China presented population expansion even during the last glacial maximum. Despite of high levels of genetic admixture between C. heterophylla and C. kweichowensis, significant ecological and morphological discrepancy as well as incomplete geographic isolation indicated that adaptive evolution triggered by divergent selection may have played important roles in incipient ecological speciation.


Asunto(s)
Corylus , Corylus/genética , ADN de Cloroplastos/genética , Ecosistema , Variación Genética , Filogenia , Filogeografía
2.
Angew Chem Int Ed Engl ; 60(4): 1839-1844, 2021 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-33058450

RESUMEN

The first electrochemical hydrolysis of hydrosilanes to silanols under mild and neutral reaction conditions is reported. The practical protocol employs commercially available and cheap NHPI as a hydrogen-atom transfer (HAT) mediator and operates at room temperature with high selectivity, leading to various valuable silanols in moderate to good yields. Notably, this electrochemical method exhibits a broad substrate scope and high functional-group compatibility, and it is applicable to late-stage functionalization of complex molecules. Preliminary mechanistic studies suggest that the reaction appears to proceed through a nucleophilic substitution reaction of an electrogenerated silyl cation with H2 O.

3.
J Sep Sci ; 40(12): 2629-2637, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28453223

RESUMEN

Nano-sized molecularly imprinted polymers for tiliroside were successfully prepared by a precipitation polymerization method. Acrylamide, ethylene glycol dimethacrylate, azobisisobutyronitrile, and acetonitrile/dimethyl sulfoxide were used as functional monomer, cross-linker, initiator, and porogen, respectively. The structural features and morphological characterization of tiliroside-imprinted polymers were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The adsorption experiments indicated that the tiliroside-imprinted polymers exhibited high selective recognition property to tiliroside. Scatchard analysis indicated that the homogeneous-binding sites were formed in the polymers. The selectivity test revealed that the adsorption capacity and selectivity of polymers to tiliroside was significantly higher than that of rutin, astragalin, and kaempferol. Finally, the tiliroside-imprinted polymers were employed as adsorbents in solid-phase extraction for the extraction of tiliroside from the ethyl acetate extract of the flowers of Edgeworthia gardneri (wall.) Meisn. The results demonstrated that the extraction recoveries of tiliroside ranged from 69.3 to 73.5% by using tiliroside-imprinted polymers coupled with solid-phase extraction method. These results indicated that the tiliroside-based molecularly imprinted solid-phase extraction method was proven to be an effective technique for the separation and enrichment of tiliroside from natural medicines.


Asunto(s)
Flavonoides/aislamiento & purificación , Flores/química , Impresión Molecular , Thymelaeaceae/química , Adsorción , Cromatografía Líquida de Alta Presión , Polímeros , Extracción en Fase Sólida
4.
J Clin Gastroenterol ; 50(8): 670-5, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27136963

RESUMEN

BACKGROUND: Acute-on-chronic liver failure (ACLF) is a major cause of hepatic death in the world, but no population-based studies have evaluated the incidence of ACLF. This study was conducted to determine the incidence and short-term outcomes of ACLF in a region of Eastern China. METHODS: In this prospective cross-sectional study, we collected data from public hospitals in Nantong city between January 1, 2005, and December 31, 2014. All hospitals with admission potential for ACLF patients were included. The primary outcome was ACLF defined as severe jaundice and coagulopathy with underlying chronic liver disease, according to diagnostic and laboratory criteria suggested by Chinese Society for Hepatology (CSH). RESULTS: During the 10-year period, a consecutive sample of 1934 ACLF patients was included in this study. The overall ACLF incidence rate over the 10-year period was 2.53 (95% confidence interval, 2.16-2.91) per 100,000 population per year, decreasing from 3.35 in 2005 to 2.06 in 2014. Chronic hepatitis B virus (HBV) infection was the leading cause of chronic liver disease and HBV reactivation was the most common cause of acute hepatic event. The 28-day mortality for the ACLF patients had a clear decline during the study period, form 50.39% in 2005 to 35.44% in 2014. CONCLUSIONS: In the Eastern China population, the incidence of ACLF is decreasing and the prognosis improving. Short-term mortality was associated with the presence of cirrhosis and growing age. While ACLF remains a life-threatening disorder, our findings suggest that nationwide and long-term cohorts should be conducted for the natural history of ACLF.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada/epidemiología , Hepatitis B Crónica/complicaciones , Cirrosis Hepática/epidemiología , Insuficiencia Hepática Crónica Agudizada/etiología , Insuficiencia Hepática Crónica Agudizada/mortalidad , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , China/epidemiología , Estudios Transversales , Femenino , Hepatitis B Crónica/epidemiología , Humanos , Incidencia , Cirrosis Hepática/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Adulto Joven
5.
Zhonghua Nei Ke Za Zhi ; 47(7): 570-3, 2008 Jul.
Artículo en Zh | MEDLINE | ID: mdl-19035169

RESUMEN

OBJECTIVE: To investigate the change and effect of SSeCKS (src suppressed c kinase substrates) in the activation of hepatic stellate cells (HSCs). METHODS: HSCs were isolated from normal rats, the change of SSeCKS mRNA expression on HSCs culture in vitro was determined using real-time PCR, protein level was determined by Western blot and immunofluorescence methods. A rat model of liver fibrosis was established. The expression and location of SSeCKS and alpha-SMA (alpha-smooth muscle actin) in liver tissues were detected by immunofluorescence methods. RESULTS: SSeCKS mRNA expression was low in freshly isolated HSCs cell and the expression increased in activated HSCs in vitro. In liver fibrosis tissue, the number of SSeCKS-positive cells was increased and these cells were distributed along the sinusoids which also contained alpha-SMA positive cells. CONCLUSION: The expression of SSeCKS was increased in activated HSCs in vitro. Therefore, SSeCKS may be involved in the liver inflammation and fibrosis.


Asunto(s)
Células Estrelladas Hepáticas/metabolismo , Cirrosis Hepática/metabolismo , Proteína Quinasa C/biosíntesis , Animales , Células Cultivadas , Modelos Animales de Enfermedad , ARN Mensajero/genética , Ratas
6.
Talanta ; 178: 299-307, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29136826

RESUMEN

In present study, magnetic molecularly imprinted polymers (MMIPs) were successfully prepared for specific recognition and selective enrichment of phloridzin from the leaves of Malus doumeri (Bois) A. Chev and rats' plasma. The magnetic Fe3O4 were prepared by the solvothermal reaction method and followed by the modification of TEOS and functionalization with APTES. Using functionalized Fe3O4 particles as the magnetic cores, phloridzin as template, ethylene glycol dimethacrylate (EGDMA) as cross-linker and 2,2-azobisisobutyonnitrile (AIBN) as initiator, the MMIPs were prepared through APTES to associate the template on the surface of the magnetic substrate. The structural features and morphological characterizations of MMIPs were performed by FT-IR, SEM, TEM, XRD, TGA and VSM. The adsorption experiments revealed that the MMIPs presented high selective recognition property to phloridzin. The selectivity experiment indicated that the adsorption capacity and selectivity of polymers to phloridzin was higher than that of baicalin and 2,3,5,4'-ttrahydroxy stilbene-2-O-ß-D-glucoside. Furthermore, the MMIPs were employed as adsorbents for extraction and enrichment of phloridzin from the leaves of M. doumeri and rats' plasma. The recoveries of phloridzin in the leaves of M. doumeri ranged from 81.45% to 90.27%. The maximum concentration (Cmax) of phloridzin in rats' plasma was detected as 12.19 ± 0.84µg/mL at about 15min after oral administration of phloridzin (200mg/kg). These results demonstrate that the prepared MMIPs are suitable for the selective adsorption of phloridzin from complex samples such as natural medical plants and biological samples.


Asunto(s)
Óxido Ferrosoférrico/química , Impresión Molecular , Florizina/análisis , Florizina/química , Polímeros/química , Polímeros/síntesis química , Adsorción , Animales , Precipitación Química , Masculino , Florizina/sangre , Florizina/aislamiento & purificación , Hojas de la Planta/química , Polimerizacion , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Extracción en Fase Sólida , Espectroscopía Infrarroja por Transformada de Fourier
7.
Medicine (Baltimore) ; 95(3): e2506, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26817889

RESUMEN

The artificial liver support system (ALSS) offers the potential to improve the prognosis of patients with acute-on-chronic liver failure (ACLF). However, the literature has been inconsistent on its survival benefits. We aimed to conduct a time series-based meta-analysis of randomized clinical trials (RCTs) and observational studies which examined differences in mortality in ACLF patients treated with ALSS or not.MEDLINE, EMBASE, OVID, and COCHRANE library database were systemically searched up to December 2014. Quality of included studies was evaluated using the Jadad score. The outcome measure was mortality at different follow-up endpoints. Odds ratios (ORs) and survival curve data were pooled for analysis.Ten studies, 7 RCTs, and 3 controlled cohorts were enrolled, involving a total of 1682 ACLF patients, among whom 842 were treated with ALSS. ALSS was found to reduce the risk of short-term (1-month and 3-month) mortality for patients with ACLF by nearly 30%. Randomized trials and observational studies provided good internal and external validity respectively. The combined Kaplan-Meier curves showed a consistent pattern of findings. Meta-analysis also suggested that ALSS might reduce medium-term (6-month and 1-year) mortality risk by 30% and long-term (3-year) mortality risk by 50% in ACLF patients.ALSS therapy could reduce short-term mortality in patients with ACLF. Meanwhile, its impacts on medium- and long-term survival seem to be promising but remained inconclusive. Clinical utility of this system for survival benefit may be implied.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada/terapia , Hígado Artificial , Humanos , Estimación de Kaplan-Meier , Ensayos Clínicos Controlados Aleatorios como Asunto , Análisis de Supervivencia
8.
Medicine (Baltimore) ; 94(23): e953, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26061326

RESUMEN

Prognostic evaluation is important for the management of patients with autoimmune hepatitis (AIH). Although some autoantibodies have been associated with disease activity and outcomes, the implication of antibodies to soluble liver antigen (anti-SLA) remains controversial. To conduct a meta-analysis of observational studies which addressed differences in clinical characteristics by anti-SLA status in patients with AIH. Three databases PUBMED, EMBASE, and OVID were systemically searched up to January 2015 using the terms "soluble liver antigen" or "liver-pancreas antigen" and "autoimmune hepatitis" with restriction to English-language. Studies were included if at least 50 patients with objective diagnosis of AIH were enrolled, anti-SLA detection was performed for the patients, and prognostic outcomes and/or disease severity were reported. Two investigators independently reviewed retrieved literature and evaluated eligibility. Discrepancy was resolved by discussion and a third investigator. Quality of included studies was evaluated using Newcastle-Ottawa Quality Assessment Scale (NOS). Data were pooled using fixed-effect or random-effect models. Prognostic outcomes included death from hepatic failure or requirement for liver transplantation, and responses to immunosuppressive therapy regarding remission or relapse. Results were combined on the odds ratio (OR) or standardized mean difference (SMD) scales. Eight studies were enrolled in this study, involving a total of 1297 AIH patients among whom 195 with anti-SLA. Pooled serum AST levels tended to be lower in anti-SLA seropositive patients. The presence of anti-SLA conferred 3.1-fold increased risk of hepatic death in AIH patients. The remission rates were comparable between anti-SLA seropositive and seronegative AIH patients, while anti-SLA positivity was associated with nearly 2-fold increased risk of relapse after drug withdrawal. Human leukocyte antigen (HLA) allotype DR3 was positively associated with anti-SLA. Antibodies to SLA may be an indicator of increased risks of hepatic death and treatment relapse for AIH patients. Our findings suggest that the anti-SLA seropositive patients should be maintained indefinitely on individually adjusted medication to improve their prognosis.


Asunto(s)
Autoanticuerpos/inmunología , Autoantígenos/inmunología , Hepatitis Autoinmune/inmunología , Autoanticuerpos/sangre , Hepatitis Autoinmune/sangre , Humanos , Pronóstico
9.
Medicine (Baltimore) ; 93(28): e338, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25526495

RESUMEN

For patients with acute-on-chronic liver failure (ACLF), artificial liver support system (ALSS) may help prolong lifespan and function as a bridge to liver transplantation (LT), but data on its long-term benefit are lacking. We conducted this prospective, controlled study to determine the efficacy of ALSS and the predictors of mortality in patients with hepatitis B virus (HBV)-associated ACLF.From January 2003 to December 2007, a total of 234 patients with HBV-associated ACLF not eligible for LT were enrolled in our study. They were allocated to receive either plasma exchange centered ALSS plus standard medical therapy (SMT) (ALSS group, n=104) or SMT alone (control group, n=130). All the patients were followed-up for at least 5 years, or until death.At 90 days, the survival rate of ALSS group was higher than that of the control group (62/104 [60%] vs 61/130 [47%], respectively; P<0.05). Median survival was 879 days in the ALSS group (43% survival at 5 years) and 649 days in the control group (31% survival at 5 years, log-rank P<0.05). ALSS was found to be associated with favorable outcome of these patients by both univariate and multivariate analysis. Multivariate Cox regression analysis also revealed that lower serum sodium levels, higher grades of encephalopathy, presence of cirrhosis, hepatorenal syndrome, and higher model for end-stage liver disease scores were independent predictors for both 90-day and 5-year mortality due to ACLF.Our findings suggest that ALSS is safe and may improve the short- and long-term prognosis of patients with HBV-associated ACLF.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada/terapia , Hepatitis B/complicaciones , Hígado Artificial , Insuficiencia Hepática Crónica Agudizada/etiología , Insuficiencia Hepática Crónica Agudizada/mortalidad , Adulto , China/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia/tendencias , Factores de Tiempo , Resultado del Tratamiento
11.
Biol Pharm Bull ; 31(1): 45-50, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18175940

RESUMEN

A safe and effective delivery system with a submicron emulsion for puerarin was studied. Puerarin submicron emulsion was prepared by a novel complex-phase inversion-high press homogenization technology. The mechanism to reduce the hemolysis side effect of puerarin was studied by blood cell counts in rabbits. The average diameter, zeta potential and entrapment efficiency of the emulsion prepared was 198.14+/-8.61 nm, -29.45+/-1.47 mV, 87.32+/-0.34%, respectively. Compared with control group, the red blood cell values, packed cell volume, plasma hemoglobin level, haptoglobin level and osmotic fragility of puerarin i.v. group was significantly different (p<0.05) at 42, 43 d, respectively. The blood cell parameter values of puerarin submicron emulsion group were not significantly different (p>0.05) in contrast to control group. Such observations indicated that the intravascular hemolysis occurred at 42, 43 d in puerarin i.v. group rabbits, the hemolysis did not occur for puerarin emulsion group rabbits. As an explanation for these results, it was proposed that the puerarin was either incorporated into the lipophilic core or intercalated between the phospholipid molecules at the interface. It could be concluded that puerarin submicron emulsions prepared markedly reduced the hemolysis effect of puerarin.


Asunto(s)
Sistemas de Liberación de Medicamentos , Hemólisis/efectos de los fármacos , Isoflavonas/administración & dosificación , Isoflavonas/efectos adversos , Animales , Emulsiones , Masculino , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Conejos
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