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1.
Eat Weight Disord ; 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33587278

RESUMEN

PURPOSE: Little is known about the association between dinner-to-bed time and obesity. Thus, this study was aimed to assess the relationships between dinner-to-bed and overweight/obesity in Chinese school-aged children in Ningbo, China. METHODS: Data of this study were based on 1667 schoolchildren (14-15 years) from 14 primary schools participated in this study in China. Anthropometric measurement of height, body weight and waist circumference (WC) was performed. Information about meal duration and other lifestyle behaviors was collected using a self-administered questionnaire. Multivariable logistic regression model was performed to assess the association between dinner-to-bed time and overweight/obesity. Restricted cubic spline regression was drawn to evaluate the shape of the relation between dinner-bed-time and the odds of overweight. RESULTS: Among the study participants, the prevalence of overweight was 17.6%, and the mean of dinner-to-bed time was 4.26 (0.93) h. In the logistic regression analysis, participants who had dinner-to-bed time less than 3 h or 3.01 ~ ≦ 4.00 h are more likely to be overweight (OR = 1.94, 95% CI 1.10-3.42; OR = 1.65, 95% CI 1.03-2.65, respectively) or characterised by abdominal obesity (OR = 3.03, 95% CI 1.86-4.95; OR = 2.61, 95% CI 1.73-3.92, respectively) compared with dinner-to-bed time more than 5 h. In addition, long dinner-to-bed time was associated with lower risks of overweight (OR = 0.83, 95% CI 0.70-0.97) and abdominal obesity (OR = 0.63, 95% CI 0.54-0.73). The cubic spline regression analysis showed that the association between dinner-to-bed time and overweight/abdominal obesity seems to be a linear. CONCLUSIONS: This study indicates that short dinner-to-bed time is associated with an increased likelihood of being overweight or characterised by abdominal obesity among Chinese school-aged children. LEVEL OF EVIDENCE: Level V; cross-section descriptive study.

2.
Public Health Nutr ; : 1-23, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33168121

RESUMEN

OBJECTIVE: To assess the prevalence of metabolic syndrome (MetS) in Chinese adults living in Ningbo and to examine the association between alcohol consumption, and MetS and its medical components. DESIGN: A representative survey in Ningbo was conducted in 2015 covering socio-demography. A food frequent questionnaire together with additional questionnaires was used to collect information on alcohol consumption, diet, demography, lifestyle, and medical information. Multivariable logistic regression and generalized linear models were used to examine the association between alcohol consumption, and both MetS and its medical components, respectively. SETTING: Ningbo, China. PARTICIPANTS: Total 2853 adults ≥20 years (44% men) in this final analysis. RESULTS: The prevalence of frequent alcohol drinkers and MetS were 29.9% and 28.0%, respectively. Significantly higher prevalence of MetS and mean values of medical components were found in the group of frequent alcohol drinkers with an exception for HDL-C, compared to less or non-alcohol drinkers. Frequent alcohol consumption was associated with higher odds of developing MetS and positively associated with medical components excepting waist circumference. CONCLUSIONS: Frequent alcohol consumption contributed to higher prevalence of MetS, and unfavorable influence on MetS and its medical components among Chinese adults. A public health intervention on alcohol restriction is necessary for the prevention and control the ongoing epidemic MetS.

3.
Food Chem ; 341(Pt 1): 128148, 2020 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-33038776

RESUMEN

The brown seaweed Undaria pinnatifida polysaccharides show various biological activities, but their hypoglycemic activity and the underlying mechanism remain unclear. Here, three fractions of sulfated polysaccharides Up-3, Up-4, and Up-5 were prepared by microwave-assisted extraction from U. pinnatifida. In vitro assays demonstrated that Up-3 and Up-4 had strong α-glucosidase inhibitory activity, and Up-3, Up-4, and Up-5 could improve the glucose uptake in insulin-resistant HepG2 cells without affecting their viability. In vivo studies indicated Up-3 and Up-4 markedly reduced postprandial blood glucose levels. Up-U (a mixture of Up-3, Up-4, and Up-5), reduced fasting blood glucose levels, increased glucose tolerance and alleviated insulin resistance in HFD/STZ-induced hyperglycemic mice. Histopathological observation and hepatic glycogen measurement showed that Up-U alleviated the damage of the pancreas islet cell, reduced hepatic steatosis, and promoted hepatic glycogen synthesis. These findings suggest that Up-U could alleviate postprandial and HFD/STZ-induced hyperglycemia and was a potential agent for diabetes treatment.

4.
Mar Drugs ; 18(9)2020 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-32867177

RESUMEN

A low fasting blood glucose level is a common symptom in diabetes patients and can be induced by high-fat diet (HFD) feeding at an early stage, which may play important roles in the development of diabetes, but has received little attention. In this study, five polysaccharides were prepared from Sargassumfusiforme and their effects on HFD-induced fasting hypoglycemia and gut microbiota dysbiosis were investigated. The results indicated that C57BL/6J male mice fed an HFD for 4 weeks developed severe hypoglycemia and four Sargassumfusiforme polysaccharides (SFPs), consisting of Sf-2, Sf-3, Sf-3-1, and Sf-A, significantly prevented early fasting hypoglycemia without inducing hyperglycemia. Sf-1 and Sf-A could also significantly prevent HFD-induced weight gain. Sf-2, Sf-3, Sf-3-1, and Sf-A mainly attenuated the HFD-induced decrease in Bacteroidetes, and all five SFPs had a considerable influence on the relative abundance of Oscillospira, Mucispirillum, and Clostridiales. Correlation analysis revealed that the fasting blood glucose level was associated with the relative abundance of Mucispinllum and Oscillospira. Receiver operating characteristic analysis indicated that Mucispinllum and Oscillospira exhibited good discriminatory power (AUC = 0.745-0.833) in the prediction of fasting hypoglycemia. Our findings highlight the novel application of SFPs (especially Sf-A) in glucose homeostasis and the potential roles of Mucispinllum and Oscillospira in the biological activity of SFPs.

5.
J Enzyme Inhib Med Chem ; 35(1): 1736-1742, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32928007

RESUMEN

Gut microbial ß-glucuronidases have the ability to deconjugate glucuronides of some drugs, thus have been considered as an important drug target to alleviate the drug metabolites-induced gastrointestinal toxicity. In this study, thiazolidin-2-cyanamide derivatives containing 5-phenyl-2-furan moiety (1-13) were evaluated for inhibitory activity against Escherichia coli ß-glucuronidase (EcGUS). All of them showed more potent inhibition than a commonly used positive control, d-saccharic acid 1,4-lactone, with the IC50 values ranging from 1.2 µM to 23.1 µM. Inhibition kinetics studies indicated that compound 1-3 were competitive type inhibitors for EcGUS. Molecular docking studies were performed and predicted the potential molecular determinants for their potent inhibitory effects towards EcGUS. Structure-inhibitory activity relationship study revealed that chloro substitution on the phenyl moiety was essential for EcGUS inhibition, which would help researchers to design and develop more effective thiazolidin-2-cyanamide type inhibitors against EcGUS.

6.
Intern Emerg Med ; 2020 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-32356137

RESUMEN

Whether the anemia increases the risk of mortality in patients with acute heart failure (AHF) remains unclear. This study aims to explore the relationship between anemia and outcomes in patients with AHF including subgroup analysis. This study included 3279 patients with hemoglobin available from the Beijing Acute Heart Failure Registry (Beijing AHF Registry) study. The primary endpoint was all-cause mortality in 1 year, and the secondary endpoint was 1-year all-cause events including all-cause death and readmission. Logistic regression models were applied to describe related variables of anemia in patients with AHF. Multivariate Cox proportional hazards models described associations of anemia with clinical outcomes in the overall cohort and subgroups. 45.4% of the patients were found anemic. They were older and had more comorbidities than non-anemic patients. Variables including older age, female, chronic kidney dysfunction (CKD), lower hematocrit, lower albumin, with loop diuretics applied, without beta-blockers, angiotensin-converting enzyme inhibitors /angiotensin receptor blockers (ACEIs/ARBs) and spironolactone applied in the emergency department (ED) were associated with anemia in AHF patients. Anemic patients had higher 1-year mortality (38.4% vs. 27.2%, p < 0.0001) and 1-year events rates (63.2% vs. 56.7%, p < 0.0001). After adjusted for covariates, anemia was associated with the increase of 1-year mortality (hazard ratio [HR] 1.278; 95% confidence interval [CI] 1.114-1.465; p = 0.0005) and 1-year events (HR 1.136; 95% CI 1.025-1.259; p = 0.0154). The severer anemia patients had higher risks both of 1-year mortality and events. In the subgroup analysis, the independent associations of anemia with 1-year mortality were shown in the subgroups including age < 75 years, male, body mass index < 25 kg/m2 and BMI ≥ 25 kg/m2, New York Heart Association (NYHA) functional class I-II and NYHA functional class III-IV, with and without cardiovascular ischemia, heart rate (HR) < 100 bpm and HR ≥ 100 bpm, systolic blood pressure (SBP) < 120 mmHg and SBP ≥ 120 mmHg, left ventricular ejection fraction (LVEF) < 40% and LVEF ≥ 40%, serum creatinine (Scr) < 133 umol/l, and with diuretics use, with and without beta-blockers use, without ACEIs/ARBs use in the ED. Anemia is associated with older age, female, CKD, volume overload, malnutrition, with loop diuretics, without beta-blockers, ACEIs/ARBs and spironolactone administration, and higher mortality and readmission in AHF. The risk associations are particular significantly obvious in younger, male, overweight, preserved LVEF, lower Scr, with diuretics and beta-blockers, without ACEIs/ARBs administration subgroups.Clinical trial No. ChiCTR-RIC-17014222.

7.
EMBO Rep ; 21(6): e49530, 2020 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-32329225

RESUMEN

FBN1 encodes asprosin, a glucogenic hormone, following furin cleavage of the C-terminus of profibrillin 1. Based on evolutionary conservation between FBN1 and FBN2, together with conserved furin cleavage sites, we identified a peptide hormone placensin encoded by FBN2 based on its high expression in trophoblasts of human placenta. In primary and immortalized murine hepatocytes, placensin stimulates cAMP production, protein kinase A (PKA) activity, and glucose secretion, accompanied by increased expression of gluconeogenesis enzymes. In situ perfusion of liver and in vivo injection with placensin also stimulate glucose secretion. Placensin is secreted by immortalized human trophoblastic HTR-8/SVneo cells, whereas placensin treatment stimulates cAMP-PKA signaling in these cells, accompanied by increases in MMP9 transcripts and activities, thereby promoting cell invasion. In pregnant women, levels of serum placensin increase in a stage-dependent manner. During third trimester, serum placensin levels of patients with gestational diabetes mellitus are increased to a bigger extent compared to healthy pregnant women. Thus, placensin represents a placenta-derived hormone, capable of stimulating glucose secretion and trophoblast invasion.

8.
Comp Immunol Microbiol Infect Dis ; 70: 101452, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32120143

RESUMEN

Canine babesiosis is an important global tick-borne infectious disease of domestic dogs and wild canids. B. gibsoni and B. vogeli are the most widespread species mainly endemic in dog population in southern and eastern regions of China. In this study, 272 blood samples were collected from pet dogs in five districts of Shenzhen, China. Babesia DNA was detected in 30 samples with an overall prevalence of 11.0 % in pet dogs in Shenzhen. The difference in the positive rate between female and male pet dogs, among different breed, and among the five sampling sites was not significant, while the age and health status of pet dogs significantly influence the positive rate of Babesia spp. infection. Sequencing results showed the presence of only B. vogeli in all of the samples tested. Sequence comparison and phylogenetic analysis revealed that all 30 strains of Babesia identified in this study shared the highest identity with B. vogeli. In sum, all results of this study showed a considerable high infection rate of Babesia spp. in pet dogs, and B. vogeli was the only Babesia species infecting pet dogs in Shenzhen city. Such information is necessary to help to elucidate the epidemiology of canine babesiosis in Shenzhen, and it is necessary to actively monitor this disease in pet dogs.


Asunto(s)
Babesia/genética , Babesiosis/epidemiología , Enfermedades de los Perros/epidemiología , Mascotas/parasitología , Animales , Babesiosis/sangre , China/epidemiología , ADN Protozoario/genética , Enfermedades de los Perros/parasitología , Perros/parasitología , Femenino , Masculino , Filogenia , Prevalencia , ARN Ribosómico 18S/genética , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/parasitología
9.
Appl Microbiol Biotechnol ; 104(5): 1883-1890, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31932892

RESUMEN

C-Glycosides, a special type of glycoside, are frequently distributed in many kinds of medicinal plants, such as puerarin and mangiferin, showing various and significant bioactivities. C-Glycosides are usually characterized by the C-C bond that forms between the anomeric carbon of sugar moieties and the carbon atom of aglycon, which is usually resistant against acidic hydrolysis and enzymatic treatments. Interestingly, C-glycosides could be cleaved by several intestinal bacteria, but whether the enzymatic cleavage of C-C glycosidic bond is reduction or hydrolysis has been controversial; furthermore, whether existence of a "C-glycosidase" directly catalyzing the cleavage is not clear. Here we review research advances about the discovery and mechanism of intestinal bacteria in enzymatic cleavage of C-C glycosidic bond with an emphasis on the identification of enzymes manipulation the deglycosylation. Finally, we give a brief conclusion about the mechanism of C-glycoside deglycosylation and perspectives for future study in this field.


Asunto(s)
Bacterias/enzimología , Bacterias/metabolismo , Proteínas Bacterianas/metabolismo , Glicósido Hidrolasas/metabolismo , Glicósidos/metabolismo , Intestinos/microbiología , Animales , Bacterias/aislamiento & purificación , Proteínas Bacterianas/genética , Biotransformación , Glicósido Hidrolasas/genética , Glicósidos/química , Glicosilación , Humanos , Estructura Molecular
10.
J Clin Ultrasound ; 48(4): 216-221, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31833078

RESUMEN

PURPOSE: The aim of this study was to investigate myocardial dysfunction and mechanical abnormalities in young patients with Graves' disease before therapy, using two-dimensional speckle tracking echocardiography. METHODS: We performed a comprehensive transthoracic echocardiographic examination, including segmental and global radial strain, and time-to-peak radial strain, in 47 young patients with hyperthyroidism and 34 healthy adults. The time-to-peak radial strain was corrected by RR interval. The variables derived from radial myocardial deformation by the six-basal, six-mid, and six-apical segmental model were compared to investigate the difference of the myocardial function between the two groups. RESULTS: Early diastolic mitral inflow velocity, E/A ratio, early diastolic mitral annular velocity, and e'/a' ratio were lower in patients with Graves' disease than in controls. The left ventricular end-diastolic volume, left ventricular end-systolic volume, stroke volume, cardiac output, heart rate, late diastolic mitral inflow velocity, and late diastolic mitral annular velocity were slightly higher in patients than in controls. Radial strain, global radial strain, and corrected time-to-peak radial strain were lower in the patient group. CONCLUSIONS: The decreased radial strain, global radial strain, and corrected time-to-peak radial strain in young patients with newly diagnosed hyperthyroidism due to Graves' disease could serve as an early sign of subclinical cardiac involvement.


Asunto(s)
Enfermedad de Graves/complicaciones , Hipertiroidismo/etiología , Disfunción Ventricular Izquierda/etiología , Función Ventricular Izquierda/fisiología , Adulto , Ecocardiografía/métodos , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Hipertiroidismo/diagnóstico por imagen , Hipertiroidismo/fisiopatología , Masculino , Persona de Mediana Edad , Válvula Mitral/fisiología , Volumen Sistólico/fisiología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/fisiopatología , Adulto Joven
11.
Sleep Breath ; 24(1): 321-328, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31858391

RESUMEN

PURPOSE: This prospectively designed study aimed to investigate the association between sleep duration and overweight in a cohort of Chinese adolescents. METHODS: A school-based cohort study with a 2-year follow-up was conducted among Chinese adolescents in Ningbo region (China). For the baseline study, 1901 school-aged Chinese children aged 12-13 years were recruited. Finally, 1510 adolescents were successfully reinterviewed in October 2018. Participants were asked to complete a self-administered questionnaire, and their heights and weights were directly measured. RESULTS: Overweight adolescents had shorter sleep duration or later bedtimes than non-overweight children in baseline (P < 0.05). In the multivariable linear regression analysis, sleep duration was marginally significantly correlated with body mass index (BMI) at baseline and significantly correlated with this parameter at a 2-year follow-up (ß = - 0.23, 95% confidence interval (CI): - 0.51 to 0.04, P < 0.1; ß = - 0.27, 95% CI: - 0.42 to - 0.11, P < 0.05, respectively). After adjusting for potential confounders, the multivariable logistic regression analysis revealed associations of a longer sleep duration at baseline with a reduced likelihood of participants being overweight both at baseline and at follow-up (adjusted odds ratio (AOR) = 0.81, 95% CI: 0.66 to 1.00, P = 0.05; AOR = 0.43, 95% CI:0.24 to 0.76, P < 0.05, respectively). CONCLUSIONS: Shorter sleep was associated with an increased likelihood of being overweight in Chinese adolescents, while a 1-h decrease in sleep per night led to a more than 50% increase in the overweight risk at the 2-year follow-up.

12.
J Cell Physiol ; 234(8): 13878-13893, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30720220

RESUMEN

Exosomes extracted from mesenchymal stem cells (MSCs) was reported to reduce myocardial ischemia/reperfusion damage. Besides, stromal-derived factor 1 (SDF1a) functions as cardiac repair after myocardial infarction (MI). Therefore, the present study aims to identify whether exosomes (Exo) released from SDF1-overexpressing MSCs display a beneficial effect on ischemic myocardial infarction. Initially, a gain-of-function study was performed to investigate the function of SDF1 in ischemic myocardial cells and cardiac endothelial cells. Coculture experiments were performed to measure potential exosomic transfer of SDF1 from MSCs to ischemic myocardial cells and cardiac endothelial cells. During the coculture experiments, exosome secretion was disrupted by neutral sphingomyelinase inhibitor GW4869 and upregulated exosomal SDF1 using SDF1 plasmid. Effects of Exo-SDF1 on cardiac function in MI mice were investigated in vivo. MSCs suppressed myocardial cell apoptosis and promoted microvascular regeneration of endothelial cells through secretion of exosomes. The addition of GW4869 led to increased apoptotic capacity of myocardial cells, decreased microvascular formation ability of endothelial cells, enhanced autophagy ability, and elevated Beclin-1 level as well as ratio of LC3II/LC3I. Overexpression of SDF1 and Exo-SDF1 inhibited apoptosis and autophagy of myocardial cells, but promoted tube formation of endothelial cells. The interference of PI3K signaling pathway promoted apoptosis and autophagy of myocardial cells, but inhibited tube formation of endothelial cells. SDF1 activated the PI3K signaling pathway. Exo-SDF1 protected cardiac function of MI mice and inhibited myocardial tissue damage. This study provided evidence that SDF1 overexpression in MSCs-derived exosomes inhibited autophagy of ischemic myocardial cells and promoted microvascular production of endothelial cells.


Asunto(s)
Apoptosis , Quimiocina CXCL12/metabolismo , Endotelio Vascular/patología , Exosomas/metabolismo , Células Madre Mesenquimatosas/metabolismo , Microvasos/patología , Infarto del Miocardio/patología , Infarto del Miocardio/terapia , Regeneración , Animales , Autofagia , Regulación hacia Abajo , Células Endoteliales/metabolismo , Exosomas/ultraestructura , Pruebas de Función Cardíaca , Masculino , Ratones Endogámicos C57BL , Infarto del Miocardio/fisiopatología , Miocardio/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal
13.
Chin Med J (Engl) ; 130(16): 1894-1901, 2017 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-28776539

RESUMEN

BACKGROUND: The emergency department (ED) has a pivotal influence on the management of acute heart failure (AHF), but data concerning current ED management are scarce. This Beijing AHF Registry Study investigated the characteristics, ED management, and short- and long-term clinical outcomes of AHF. METHODS: This prospective, multicenter, observational study consecutively enrolled 3335 AHF patients who visited 14 EDs in Beijing from January 1, 2011, to September 23, 2012. Baseline data on characteristics and management were collected in the EDs. Follow-up data on death and readmissions were collected until November 31, 2013, with a response rate of 92.80%. The data were reported as median (interquartile range) for the continuous variables, or as number (percentage) for the categorical variables. RESULTS: The median age of the enrolled patients was 71 (58-79) years, and 46.84% were women. In patients with AHF, coronary heart disease (43.27%) was the most common etiology, and myocardium ischemia (30.22%) was the main precipitant. Most of the patients in the ED received intravenous treatments, including diuretics (79.28%) and vasodilators (74.90%). Fewer patients in the ED received neurohormonal antagonists, and 25.94%, 31.12%, and 33.73% of patients received angiotensin converting enzyme inhibitors/angiotensin receptor blockers, beta-blockers, and spironolactone, respectively. The proportions of patients who were admitted, discharged, left against medical advice, and died were 55.53%, 33.58%, 7.08%, and 3.81%, respectively. All-cause mortalities at 30 days and 1 year were 15.30% and 32.27%, respectively. CONCLUSIONS: Substantial details on characteristics and ED management of AHF were investigated. The clinical outcomes of AHF patients were dismal. Thus, further investigations of ED-based therapeutic approaches for AHF are needed.


Asunto(s)
Insuficiencia Cardíaca , Enfermedad Aguda , Anciano , Beijing , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sistema de Registros
14.
Parasitol Res ; 116(9): 2449-2456, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28707028

RESUMEN

During the investigation of actinosporean fauna diversity from commercial fish ponds in Hubei Province, China, a novel aurantiactinomyxon type was found from Branchiura sowerbyi. Spore body of the aurantiactinomyxon was ellipsoidal in side view and triangular in apical view, 15.5 ± 0.5 (14.5-16.4) µm in diameter; three leaf-like caudal processes were approximately equal, measuring 13.2 ± 0.9 (11.5-16.2) µm long and 7.4 ± 0.4 (6.7-8.0) µm wide at the base; three polar capsules were located at the apex of spore body, globular in apical view, 2.2 ± 0.1 (2.0-2.3) µm in diameter, and pyriform in side view, 2.5 ± 0.2 (2.3-2.9) µm in length and 2.0 ± 0.2 (1.8-2.4) µm in width; a total of 32 germ cells were observed within the sporoplasm. Ultrastructural analysis showed that the development was asynchronous between pansporocysts but synchronous within a pansporocyst. The formation of sporoblast and the development of sporogonic stage were also described and discussed. The 18S ribosomal DNA sequences of the current aurantiactinomyxon type corresponded to that of a previously reported Thelohanellus testudineus, suggesting that the newly identified aurantiactinomyxon type is the actinosporean stage in the life cycle of T. testudineus.


Asunto(s)
Arguloida/parasitología , Enfermedades de los Peces/parasitología , Carpa Dorada/parasitología , Myxozoa/clasificación , Myxozoa/aislamiento & purificación , Animales , China , ADN Ribosómico/genética , Estadios del Ciclo de Vida , Myxozoa/genética , Oligoquetos , Filogenia , ARN Ribosómico 18S/genética
15.
Chemosphere ; 161: 242-250, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27434254

RESUMEN

Minerals including Al2O3, SiO2 and CaO are predominant matrixes in waste, and are thought to facilitate lead (Pb) emission control. This study distinguished the inhibition of each mineral on common stable Pb-containing compounds, including highly volatile PbCl2 and less volatile PbO. Al2O3 can lower the volatilization temperature of Pb by 29 °C due to the generation of a eutectic compound and play a minor but non-negligible role in reducing Pb volatilization. The most conspicuous inhibition effect was exerted by SiO2 and a mixture of Al2O3 and SiO2, which completely integrated PbO into the glass phase at 690 °C and prohibited its migration. In contrast, SiO2 had no significant inhibition on volatile PbCl2. CaO inhibited PbO volatilization in the absence of oxygen by controlling its diffusion, while it converted PbO to Ca2PbO4 in the presence of oxygen, thus controlling Pb diffusion and decreasing the Pb volatilization ratio and rate. The influence of CaO on PbCl2 was complex because CaO can convert PbCl2 to PbO with formation of CaCl2, and CaCl2 can also be a Cl-donor for PbO. The roles of mineral matrixes in Pb conversion were shown to be important for Pb emission control.


Asunto(s)
Contaminantes Atmosféricos/química , Óxido de Aluminio/química , Compuestos de Calcio/química , Plomo/química , Óxidos/química , Dióxido de Silicio/química , Incineración , Volatilización
16.
Sci Rep ; 6: 23197, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-27034259

RESUMEN

The inhibitory effects of four amino compounds on the formation of chlorobenzenes (CBzs)--dioxin precursors and indicators, and the inhibitory mechanisms were explored. The results show NH4H2PO4 can decrease the total yields of CBzs (1,2di-CBz, 1,3di-CBz, 1,4di-CBz, penta-CBz and hexa-CBz) by 98.1%±1.6% and 96.1%±0.7% under air and nitrogen flow. The inhibitory effects indicated by the total yields of CBzs follow the order NH4H2PO4 > NH4HF2 > (NH4)2SO4 > NH4Br under air flow and NH4H2PO4 ≈ (NH4)2SO4 ≈ NH4HF2 >NH4Br under nitrogen flow. The inhibition mechanism revealed by thermal analysis that CuCl2 was converted to CuPO3 by reacting with NH4H2PO4 below 200 °C, which can block the transfer of chlorine and formation of C-Cl bonds at 350 °C. The effects of the other three inhibitors were weaker because their reactions with CuCl2, which form other copper compounds, and the reaction of CuCl2 with carbon, which forms C-Cl bonds, were almost simultaneous and competitive. Oxygen influenced the yield of CBzs obviously, and the total yield of five CBzs sharply increased with oxygen. Because of their high efficiency, low environmental impact, low cost, and availability, amino compounds--especially NH4H2PO4--can be utilized as inhibitors of CBzs during incineration.

17.
Chin J Nat Med ; 14(3): 236-40, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27025372

RESUMEN

This study aimed to trace sources and quantitatively analyze the specnuezhenide content of circular Fructus Ligustri Lucidi for clinical use. Different specifications of Fructus Ligustri Lucidi were identified using DNA barcoding technology and the specnuezhenide content was analyzed by High Performance Liquid Chromatography (HPLC). The ITS sequence of circular Fructus Ligustri Lucidi was identical to that of standard privet, which was determined through botanical identification. ITS sequence similarity between circular Fructus Ligustri Lucidi and Fructus Ligustri Lucidi which was registered in NCBI ranged from 99.5% to 100%. The sequences of circular and other Fructus Ligustri Lucidi were clustered in a Neighbor-Joining tree with bootstrap value of 95, and these sequences could be distinguished from adulterants. Conforming to pharmacopoeia standard, the average specnuezhenide content of circular Fructus Ligustri Lucidi was higher than that of chicken waist Fructus Ligustri Lucidi. Circular Fructus Ligustri Lucidi derived from Ligustrum lucidum Ait. and the specnuezhenide content was higher in circular Fructus Ligustri Lucidi than that in chicken waist Fructus Ligustri Lucidi.


Asunto(s)
Ligustrum/clasificación , Cromatografía Líquida de Alta Presión , Código de Barras del ADN Taxonómico , ADN de Plantas , Frutas/química , Glucósidos/aislamiento & purificación , Ligustrum/química , Ligustrum/genética , Medicina China Tradicional , Reacción en Cadena de la Polimerasa , Piranos/aislamiento & purificación , Control de Calidad
18.
Chemosphere ; 117: 353-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25150687

RESUMEN

Poly(vinyl chloride) (PVC) as a widely used plastic that can promote the volatilization of heavy metals during the thermal treatment of solid waste, thus leading to environmental problems of heavy metal contamination. In this study, thermogravimetric analysis (TGA) coupled with differential scanning calorimeter, TGA coupled with Fourier transform infrared spectroscopy and lab-scale tube furnace experiments were carried out with standard PVC and PbO to explicate the thermochemical reaction mechanism of PVC with semi-volatile lead. The results showed that PVC lost weight from 225 to 230°C under both air and nitrogen with an endothermic peak, and HCl and benzene release were also detected. When PbO was present, HCl that decomposed from PVC instantly reacted with PbO via an exothermal gas-solid reaction. The product was solid-state PbCl2 at <501°C, which was the most volatile lead-containing compound with a low melting point and high vapor pressure. At >501°C, PbCl2 melted, volatilized and transferred into flue gas or condensed into fly ash. Almost all PbCl2 volatilized above 900°C, while PbO just started to volatilize slowly at this temperature. Therefore, the chlorination effect of PVC on lead was apt to lower-temperature and rapid. Without oxygen, Pb2O was generated due to the deoxidizing by carbon, with oxygen, the amount of residual Pb in the bottom ash was significantly decreased.


Asunto(s)
Contaminantes Ambientales/química , Incineración , Plomo/química , Óxidos/química , Cloruro de Polivinilo/química , Eliminación de Residuos , Rastreo Diferencial de Calorimetría , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría
19.
J Hazard Mater ; 276: 241-52, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-24887126

RESUMEN

Due to the heterogeneity of metal distribution, it is challenging to identify the speciation, source and fate of metals in solid samples at micro scales. To overcome these challenges single particles of air pollution control residues were detected in situ by synchrotron microprobe after each step of chemical extraction and analyzed by multivariate statistical analysis. Results showed that Pb, Cu and Zn co-existed as acid soluble fractions during chemical extraction, regardless of their individual distribution as chlorides or oxides in the raw particles. Besides the forms of Fe2O3, MnO2 and FeCr2O4, Fe, Mn, Cr and Ni were closely associated with each other, mainly as reducible fractions. In addition, the two groups of metals had interrelations with the Si-containing insoluble matrix. The binding could not be directly detected by micro-X-ray diffraction (µ-XRD) and XRD, suggesting their partial existence as amorphous forms or in the solid solution. The combined method on single particles can effectively determine metallic multi-associations and various extraction behaviors that could not be identified by XRD, µ-XRD or X-ray absorption spectroscopy. The results are useful for further source identification and migration tracing of heavy metals.


Asunto(s)
Metales/química , Sincrotrones , Análisis Multivariante
20.
Shanghai Kou Qiang Yi Xue ; 22(6): 655-8, 2013 Dec.
Artículo en Chino | MEDLINE | ID: mdl-24469127

RESUMEN

PURPOSE: To observe the effect of subcutaneous ectopic osteogenesis using different proportional mixtures of hydroxyapatite (HAP) and human mandible in nude mice. METHODS: After obtaining external oblique ridge of mandible, autologous bone was mixed with HAP according to certain proportion. The mixtures were divided into 5 groups (group A: autologous bone/HAP=2/1; Group B: autologous bone/HAP=1/1; Group C: autologous bone/HAP=1/2; Group D: autologous bone/HAP=a quarter; Group E: HAP). The 5 groups of mixtures were respectively implanted into nude mice subcutaneously. After 8 weeks, the specimens were obtained and hard tissue sections were completed. The new bone formation was measured after trinitrophenol staining. The data was analyzed with SPSS 13.0 software package. RESULTS: The hard tissue section showed that new ectopic bone formation area was 9.1% (Group A), 16.1% (Group B), 6.1% (Group C), 3.8% (Group D), and 1.3% (Group E), respectively. New bone formation was the most in group B, while it was the least in group E. Significant differences were found between group B and other groups(P<0.05). However, there was no significant difference between group E and group C or D (P>0.05). The retention rate of HAP was the most in group E (30.3%) and the least (16.3%) in group A. CONCLUSIONS: During 8 weeks, human autologous bone mixed with HAP helps new bone formation in nude mice. The best ratio autologous bone and HAP was 1:1. This study provides certain reference basis for dentist to make lifting surgery outside the maxillary sinus using artificial bone graft. Supported by Science and Technology Project of Ningxia Hui Autonomous Region (2011zys271).


Asunto(s)
Durapatita , Osificación Heterotópica , Animales , Humanos , Mandíbula , Ratones , Ratones Desnudos
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