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1.
Ecotoxicol Environ Saf ; 198: 110666, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32361493

RESUMO

Hardness is one important water quality parameter that influences the toxicity of cadmium. Several studies have derived water quality criteria (WQC) for cadmium, but most of these studies did not consider environmental factors. Moreover, few studies considered environmental factors when carrying out ecological risk assessments (ERA) based on environmental factors. In this research, six native aquatic organisms in the Shaying River were adopted to conduct toxicity tests for cadmium. By combining published toxicity data for cadmium with hardness values and toxicity data from this study, hardness-dependent WQC were established. When normalized to a hardness of 100 mg/L CaCO3, the criterion maximum concentration (CMC) of 6.46 µg/L and criterion continuous concentration (CCC) of 1.49 µg/L in the Shaying River Basin were derived according to the USEPA guidelines. The acute predicted no effect concentrations (PNECs) derived by species sensitivity distribution (SSD) methods based on log-logistic, log-normal and Burr Type III models were 1.03, 2.41 and 1.66 µg/L, respectively. Recommended WQC values finally expressed as a function of hardness: (1) CMC=(1.136672-0.041838 × lnH) × e0.9969×lnH-2.6676; and (2) CCC=(1.101672-0.041838 × lnH) × e1.0083×lnH-6.1156. In addition, three tiers of ERA of cadmium in surface waters were conducted based on hardness obtained during different seasons in the Shaying River using the hazard quotient (HQ), the margin of safety (MOS10), and the joint probability (JPC) methods. In tiered 1, 2, and 3 ERA, cadmium exposure concentrations were standardized to a hardness of 100 mg/L. The three levels of the ERA method in the tiered framework gave consistent results: the ecological risks of cadmium in the Shaying River Basin were at acceptable levels. The present study provides a reference for the derivation of WQC and risk assessment of pollution affected by differences in aquatic species and water quality factors such as hardness.

2.
Lipids Health Dis ; 19(1): 93, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32410711

RESUMO

BACKGROUND: To evaluate the associations between maternal serum concentrations of high-density lipoprotein cholesterol (HDL-c) throughout pregnancy and neonatal birth weight (BW) and small for gestational age (SGA) births. METHODS: A prospective cohort of 2241 pregnant women was followed from recruitment to delivery in three hospitals in Beijing, China between January 2014 and December 2017. Maternal fasting serum lipids concentrations were measured at gestational week 6-12, 16, 24 and 36. Major outcome was neonatal BW. The associations between maternal HDL-c and BW were estimated by linear regression and linear mixed-effects models. Odds ratios (ORs) and 95% confidence intervals of SGA births in relation to HDL-c were evaluated via logistic regression analysis. RESULTS: There was a tendency that mothers with higher HDL-c concentrations throughout gestation gave birth to infants with lower BW. A negative association was found between maternal HDL-c concentrations and BW at 24th and 36th gestational weeks (B = - 34.044, P = 0.034; B = - 53.528, P = 0.000). The HDL-c trend of change was inversely associated with BW (B = - 442.736, P = 0.000). Mothers with SGA neonates had higher serum HDL-c concentration at the 36th gestational week (P < 0.01). The incidences of SGA in the three groups (HDL-c: 1.84-2.23 mmol/L, 2.24-2.59 mmol/L and ≥ 2.60 mmol/L) were higher than the group with the lowest concentration of HDL-c (< 1.83 mmol/L) (P < 0.01, P < 0.01, P < 0.001) at 36th week. Higher maternal HDL-c concentrations at 36th week (HDL-c: 1.84-2.23 mmol/L, 2.24-2.59 mmol/L and ≥ 2.60 mmol/L) were positively associated with the incidence of SGA (OR = 1.900, P = 0.008; OR = 1.893, P = 0.008; OR = 1.975, P = 0.004). The HDL-c trend of change was positively associated with SGA births (OR = 9.772, P = 0.000). CONCLUSIONS: Maternal serum HDL-c concentrations were inversely associated with BW at 24th and 36th gestational weeks. The high concentrations of HDL-c at the 36th gestational week increased the risk of SGA. The maternal HDL-c trend of change across pregnancy was associated with smaller neonatal size.

3.
J Anim Sci Biotechnol ; 11: 50, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32426132

RESUMO

[This corrects the article DOI: 10.1186/s40104-015-0004-5.].

4.
Artigo em Inglês | MEDLINE | ID: mdl-32243686

RESUMO

The contradiction between the rising demands of optical chirality sensing and the failure in chiral detection of cryptochiral compounds encourages researchers to find new methods for chirality amplification. Inspired by planar chirality and the host-guest recognition of pillararenes, we establish a new concept for amplifying CD signals of cryptochiral molecules by pillararene host-guest complexation induced chirality amplification. The planar chirality of pillararenes is induced and stabilized in the presence of the chiral guest, which makes the cryptochiral molecule detectable by CD spectroscopy. Several chiral guests are selected in these experiments and the mechanism of chiral amplification is studied with a non-rotatable pillararene derivative and density functional theory calculations. We believe this work affords deeper understanding of chirality and provides a new perspective for chiral sensing.

6.
Sci Total Environ ; 725: 138482, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-32304969

RESUMO

China produces approximately half of the world's pork at a high environmental cost. Implementing mitigation measures requires a better understanding of pig farming systems that are often diverse in practice. Nutrient uses and losses can be largely altered due to these variations but have not, however, been fully evaluated; moreover, attention is rarely paid to pollution swapping. Our study evaluated carbon (C) and nitrogen (N) flows among pig farms on the North China Plain using the mass flow approach. The impacts of advanced mitigation measures on nitrogen use efficiency (NUE) and on C and N emissions were further analyzed via scenario analyses. The results showed that large variations among farms were observed by comparing the best-performing farms ("top 20%") with the "other" farms; the comparisons showed 31.3 vs. 21.3% for the system NUE, 3.0 vs. 5.7 kg N ·100 kg liveweight gain (LWG)-1 for manure N losses, and 108.1 vs. 146.4 kg CO2-eg·100 kg LWG-1 for greenhouse gas (GHG) emissions, respectively. Lower system NUE was caused by lower NUEs of pigs, followed by high N emissions from manure and excessive manure application. Scenario analyses indicated that the total N loss of systems can be mitigated by 10-13% through dietary manipulation and by 26%, 27%, and 13% by low-emission storage, biogas production with improved storage, and balanced fertilization, respectively. Anaerobic digestion was solely effective for GHG mitigation (46% reduction), but no impacts were observed for all other low-NH3 measures. Combining mitigation measures simultaneously decreased total N and GHG losses by 56% and 54%, respectively, and increased the system NUEs by 89%. The wide variations among farms suggest largely attainable improvements in productivity and nutrient use by closing the management gaps related to these factors. Proper combinations of advanced measures are further needed to achieve more effective mitigation goals for multiple pollutants.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32346492

RESUMO

Coronavirus disease (COVID-19) was first diagnosed in Wuhan in December 2019. The World Health Organization defined the subsequent outbreak of COVID-19 worldwide as a public health emergency of international concern. Epidemiological data indicate that at least 20% of COVID-19 patients have severe disease. In addition to impairment of the respiratory system, acute kidney injury (AKI) is a major complication. Immune damage mediated by cytokine storms and concomitant AKI is a key factor for poor prognosis. Based on previous experience of blood purification for patients with severe acute respiratory syndrome and Middle East respiratory syndrome combined with clinical front-line practice, we developed a blood purification protocol for patients with severe COVID-19. This protocol is divided into four major steps. The first step is to assess whether patients with severe COVID-19 require blood purification. The second step is to prescribe a blood purification treatment for patients with COVID-19. The third step is to monitor and adjust parameters of blood purification. The fourth step is to evaluate the timing of discontinuation of blood purification. It is expected that blood purification will play a key role in effectively reducing the mortality of patients with severe COVID-19 through the standardized implementation of the present protocol.

9.
ChemSusChem ; 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32329562

RESUMO

Lignin, an underutilized lignocellulosic component, is regarded as a rich reservoir for the production of aromatic chemicals and fuels. Despite extensive researches in recent years, the fully unlocking lignin's potential is far from being achieved. Photocatalysis that uses sustainable solar energy to drive lignin conversion under mild conditions has been identified as a promising strategy and received growing research interest. The purpose of this review is to present a critical introduction to the photocatalytic conversion of lignin, including a summary of lignin conversion pathways and mechanisms, and the latest cutting-edge innovations on photocatalyst design and reactor construction. Moreover, the screening of solvents and regulation of other key factors that are involved in lignin photocatalytic conversion are also elucidated. Future perspectives and challenges on photocatalytic conversion of lignin to valuable products are provided finally.

10.
Org Lett ; 22(8): 2995-2998, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32237750

RESUMO

Alternarin A (1), a rearranged drimane meroterpenoid characterized by a thioglycerate moiety, was isolated together with two known analogues from the coral-associated fungi Alternaria sp. ZH-15. Its structure was determined based on spectroscopic analysis, modified Mosher's method, and TDDFT/ECD calculations. In a primary cultured cortical neuronal network, compound 1 effectively inhibited the activity of spontaneous synchronous Ca2+ oscillations and 4-aminopyridine induced epileptic discharges in the low micromolar concentration range.

11.
Mol Biol Rep ; 47(5): 4077-4086, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32248383

RESUMO

Cancer-related deaths did not apparently decrease in the past decades despite aggressive treatments. It's reported that cancer will become the leading cause of death worldwide in the twenty-first century. Increasing evidence has revealed that lncRNAs will emerge as promising cancer biomarkers or therapeutic targets in cancer treatment. LncRNA-ATB, a long noncoding RNA activated by TGF-ß, was found to be abnormally expressed in certain cancers and participate in the development and progression of tumors. In addition, aberrant lncRNA-ATB expression was also associated with clinical characteristics of tumors. The purpose of this review is to summarize functions and underlying mechanisms of lncRNA-ATB in tumors, and discuss whether lncRNA-ATB can be a biomarker and therapeutic target in cancers.

12.
Sensors (Basel) ; 20(6)2020 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-32235791

RESUMO

A vehicle target detection and information extraction scheme based on NI (National Instruments) myRIO is designed in this paper. The vehicle information acquisition and processing method based on image recognition is used to design a complete vehicle detection and information extraction system. In the LabVIEW programming environment, the edge detection method is used to realize the vehicle target detection, the pattern matching method is used to realize the vehicle logo recognition, and the Optical Character Recognition (OCR) character recognition algorithm is used to realize the vehicle license plate recognition. The feasibility of the design scheme in this paper is verified through the actual test and analysis. The scheme is intuitive and efficient, with the high recognition accuracy.

13.
iScience ; 23(4): 100985, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32240952

RESUMO

An iron-catalyzed highly anti-Markovnikov selective, enantioselective hydrosilylation of vinylcyclopropanes with PhSiH3 was reported for the preparation of valuable chiral allylic silanes via stereospecific C-C bond cleavage. Simultaneously, difficultly prepared chiral VCPs could be also obtained with moderate to excellent enantioselectivity via this kinetic resolution pathway. The chiral Z-allylic silanes could be converted to various chiral allylic derivatives. A possible mechanism via an iron-silyl species was proposed based on experimental and computational studies.

14.
J Infect Dis ; 221(Supplement_2): S279-S287, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32176792

RESUMO

BACKGROUND: This prospective study compared pharmacokinetics (PK) and pharmacodynamics (PD) of linezolid in patients with sepsis receiving continuous venovenous hemofiltration (CVVH) with patients receiving extended daily hemofiltration (EDH). METHODS: Patients with sepsis treated with linezolid and CVVH or EDH were included. Serial blood samples were collected and linezolid concentrations measured. PKs were analyzed using Pmetrics. Monte Carlo simulations were used to evaluate PD target achievement. RESULTS: From 20 patients, 320 blood samples were collected for PK and PD analysis. PK profiles of linezolid were best described by a 2-compartment model. PK parameters were not significantly different between EDH and CVVH groups and were associated with body weight, renal replacement therapy (RRT) duration, and sequential organ failure assessment score. Monte Carlo simulations showed poor fractional target attainment for a minimum inhibitory concentration (MIC) of 2 mg/L with standard 600 mg intravenous administration every 12 hours. CONCLUSIONS: Patients with sepsis receiving RRT exhibited variability in PK/PD parameters for linezolid. PK parameters were not significantly different between CVVH- and EDH-treated patients. Higher probability of target attainment would be achievable at a MIC of 2 mg/L in EDH patients. Higher linezolid doses should be considered for patients on RRT to achieve adequate blood levels.

16.
Molecules ; 25(4)2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32093273

RESUMO

5,6,7,8,3,4'-Hexamethoxyflavone, also called nobiletin (NOB), widely found in the citrus peel, is one of the main byproducts in citrus processing. NOB is considered safe, but its safety for women during pregnancy is unknown. Therefore, the effect of NOB on apoptosis in human choriocarcinoma trophoblast cells (BeWo cells) was evaluated. Cells were divided into four groups and cultured with different concentrations of NOB (0, 10, 33, and 100 µM) for 12, 24, 36, and 48 h respectively. Cell viability was detected by CCK-8 assay, cell morphology was detected by a Cell Imaging Multi-Mode Reader, and cell cycle and apoptosis were detected by flow cytometry. Cleaved PARP level, the expressions of B cell lymphoma 2 (BCL2) family proteins, and p53 pathway proteins were detected by Western blot. The results showed that after 48 h of cell culture, the cell viability was decreased significantly, but apoptosis was significantly increased. Compared to the cells without NOB treatment, the cells treated with NOB at 10 or 33 µΜ showed no significant differences in the number of suspended cells or late apoptosis rate, except the increase of cell viability. Treatment of NOB at the concentration of 100 µM improved cell viability, attenuated apoptosis, decreased suspended cells, and did not alter the G1 phase arrest, compared with the non-NOB-treated group after 48 h of culturing. The 100 µΜ NOB treatment increased the levels of BCL2 and BCLXL, and decreased p53 accumulation in BeWo cells at 48 h, but had no effect on the expression of BAX, BAK, BAD, p21, and G1 phase arrest. These findings provide evidence that NOB (10, 33, and 100 µΜ) was safe for BeWo cells. NOB at the concentration of 100 µΜ could attenuate apoptosis in BeWo cells, which might be helpful to prevent pregnancy-related diseases caused by apoptosis.

17.
Stem Cell Res Ther ; 11(1): 38, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992369

RESUMO

BACKGROUND: As important players in cell-to-cell communication, exosomes (exo) are believed to play a similar role in promoting fracture healing. This study investigated whether exosomes derived from bone marrow mesenchymal stem cells (BMMSC-Exos) could improve fracture healing of nonunion. METHODS: BMMSC-Exos were isolated and transplanted into the fracture site in a rat model of femoral nonunion (Exo group) every week. Moreover, equal volumes of phosphate-buffered saline (PBS) and exosome-depleted conditioned medium (CM-Exo) were injected into the femoral fracture sites of the rats in the control and CM-Exo groups. Bone healing processes were recorded and evaluated by radiographic methods on weeks 8, 14 and 20 after surgery. Osteogenesis and angiogenesis at the fracture sites were evaluated by radiographic and histological methods on postoperative week 20. The expression levels of osteogenesis- or angiogenesis-related genes were evaluated in vitro by western blotting and immunohistochemistry. The ability to internalize exosomes was assessed using the PKH26 assay. Altered proliferation and migration of human umbilical vein endothelial cells (HUVECs) and mouse embryo osteoblast precursor cells (MC3TE-E1s) treated with BMMSC-Exos were determined by utilizing EdU incorporation, immunofluorescence staining, and scratch wound assay. The angiogenesis ability of HUVECs was evaluated through tube formation assays. Finally, to explore the effect of exosomes in osteogenesis via the BMP-2/Smad1/RUNX2 signalling pathway, the BMP-2 inhibitors noggin and LDN193189 were utilized, and their subsequent effects were observed. RESULTS: BMMSC-Exos were observed to be spherical with a diameter of approximately 122 nm. CD9, CD63 and CD81 were expressed. Transplantation of BMMSC-Exos obviously enhanced osteogenesis, angiogenesis and bone healing processes in a rat model of femoral nonunion. BMMSC-Exos were taken up by HUVECs and MC3T3-E1 in vitro, and their proliferation and migration were also improved. Finally, experiments with BMP2 inhibitors confirmed that the BMP-2/Smad1/RUNX2 signalling pathway played an important role in the pro-osteogenesis induced by BMMSC-Exos and enhanced fracture healing of nonunion. CONCLUSIONS: Our findings suggest that transplantation of BMMSC-Exos exerts a critical effect on the treatment of nonunion by promoting osteogenesis and angiogenesis. This promoting effect might be ascribed to the activation of the BMP-2/Smad1/RUNX2 and the HIF-1α/VEGF signalling pathways.

18.
Biomol NMR Assign ; 14(1): 111-114, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31939002

RESUMO

Recent applications of phage therapy in localized wound and drug-resistant bacterial infection have brought bacteriophage back to the spotlight. While these works demonstrated the safety and effectiveness of engineered bacteriophages in human patients, the exact molecular machinery behind the bacteria killing remains largely uncharacterized. This is particularly noticable outside Escherichia coli phages, as most studies are based on bacteriophages of this Gram-negative model bacterium. In the attempt to extent our understanding to the bacteriophage of Gram-positive bacteria, we chose the host hijacking module of Bacillus subtilis phage SPO1 for systemic functional and structural studies. Gp49, an acidic protein located within operon 4 of this module, is believed to have a role during the host takeover event. Here we describe the complete resonance assignment of Gp49, which shares no sequence homology with any known protein, as the basis for the structure determination and further mechanism study.

19.
Crit Care Med ; 48(3): e209-e218, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31804299

RESUMO

OBJECTIVES: We performed a national cross-sectional survey to determine the epidemiologic characteristics of patients with sepsis in ICU in China. DESIGN: A cross-section survey study. SETTING: Forty-four hospitals in mainland China from December 1, 2015, to January 31, 2016. PATIENTS: All septic patients diagnosed according sepsis-1 criteria admitted to participating ICU. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We recorded demographic, physiologic, and microbiological data with follow-up for 90 days or death, if sooner. The frequency of sepsis and 90-day mortality rate were computed, and the relationship with gross domestic product determined. Multivariate logistic regression analysis was used to determine risk factors for 90-day mortality in patients with sepsis. Two-thousand three-hundred twenty-two patients with sepsis were included in the analysis, of whom 786 patients (33.9%) had hospital-acquired sepsis. The most common infection site was the lung (68.2%), followed by abdomen (26.6%) and bloodstream (7.8%). The frequency of sepsis in the ICU was 20.6 cases per 100 ICU admissions (95% CI, 15.8-25.4) with a 90-day mortality of 35.5%. The proportion of sepsis, severe sepsis, and septic shock were 3.10%, 43.6%, and 53.3% with a 90-day mortality of 2.78%, 17.69%, and 51.94%, respectively. Older age, low body weight, higher Sequential Organ Failure Assessment score, the number of systemic inflammatory response syndrome criteria, comorbid with heart failure, hematologic cancer, immunosuppression, higher level of lactate, infection site (pneumonia and bloodstream) were associated with 90-day mortality. CONCLUSIONS: Sepsis affects a fifth of patients admitted to ICUs in mainland China with a 90-day mortality rate of 35.5%. Our findings indicate that a large burden of sepsis, and we need to focus on sepsis as a quality improvement target in China given the high mortality. In addition, further studies are needed to delineate the epidemiology of sepsis outside the ICU.

20.
Liver Int ; 40(2): 298-307, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31674705

RESUMO

BACKGROUND & AIMS: Trends in long-term mortality rates for viral hepatitis in East and Southeast Asia have been rarely reported. The aim of our study was to explore the long-term trends in viral hepatitis mortality rates in East and Southeast Asian countries between 1987 and 2015 and provide predictions of mortality to 2030. METHODS: We obtained viral hepatitis mortality data from the WHO Mortality Database for six East and Southeast Asian countries between 1987 and 2015. We produced choropleth maps of viral hepatitis mortality rates in 1987 and 2015 in East and Southeast Asia to illustrate geographic variations. We made predictions of mortality rates for each included country until the year 2030 using a series of joinpoint models. RESULTS: Viral hepatitis mortality rates declined in China (the average annual percent change (AAPC) = -5.1%, 95% CI: -7.5, -2.6), Singapore (AAPC = -5.4%, 95% CI: -7.5, -3.2), and the Philippines (AAPC = -3.4%, 95% CI: -4.9, -1.8). In contrast, Japan, the Republic of Korea, and Malaysia have experienced increasing trends in mortality rates, followed by decreasing trends. Our predictions indicate that all countries will experience slight to moderate downward trends until 2030. CONCLUSION: Favourable decreasing trends have been noted in East and Southeast Asian countries, which may not only inform the control and management of viral hepatitis in this region but also guide the prevention of viral hepatitis deaths in another region with a similar viral hepatitis epidemic.

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