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1.
Ecotoxicol Environ Saf ; 203: 111000, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32736119

RESUMO

Microplastics are identified as a great threat to marine environments. However, knowledge of their impacts on phytoplankton, especially for the diatoms is scarce. Herein, the effects of different polyvinyl chloride (PVC) microplastic concentrations and contact times (24, 48, 72 and 96 h) on the Fv/Fm and cell density of Phaeodactylum tricornutum (B255), Chaetoceros gracilis (B13) and Thalassiosira sp. (B280) were investigated to evaluate the toxic effects of microplastics on marine diatoms. The effects of PVC microplastics on the morphology of the diatoms was observed by SEM. The order of sensitivity to 1 µm PVC microplastics among three marine diatoms was B13 > B280 > B255, showing that the toxic effects varied with different microalgae species. Furthermore, the presence of a siliceous cell wall played a minimal role in protecting cells from the physical attack of PVC microplastics, with no significant difference from the common cell wall. PVC microplastics caused dose-dependent adverse effects on three marine diatoms. High PVC concentrations (200 mg/L) reduced the chlorophyll content, inhibited Fv/Fm, and affected the photosynthesis of three marine diatoms. The PVC microplastics adsorbed and caused physical damage on the structure of algal cells. Interactions between PVC microplastics and diatoms may be the probable reason for the negative effects of PVC on diatoms.

2.
Mikrochim Acta ; 187(8): 424, 2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32621131

RESUMO

CoMoO4 materials were prepared through a simple hydrothermal method and developed as highly efficient peroxidase mimics for colorimetric determination of H2O2. Based on the different experimental conditions in the synthesis process, the CoMoO4 materials present distinct morphologies, structures, surface properties, and peroxidase mimetic activities. Among them, CoMoO4 nanobelts (NBs) display the best intrinsic peroxidase mimetic abilities due to the high-energy (100) facet exposed, more Co active sites at (100) facet, more negative potential, and larger specific surface area. It can efficiently catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2 to generate a blue oxide. In view of the excellent peroxidase mimetic catalytic activity of CoMoO4 NBs, a rapid, convenient, and ultrasensitive method was successfully established for the visual and colorimetric determination of H2O2. The method exhibits good selectivity, practicability, stability, and reusability, and has a detection limit of 0.27 µM. The peroxidase mimetic catalytic mechanism of CoMoO4 NBs was illustrated according to the kinetic and active species trapping experiments. The method has a good potential for rapid and sensitive determination of H2O2 for biomedical analysis. Graphical abstract Schematic presentation of the process of CoMoO4 nanobelts catalyzing the oxidation of peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2 to generate a typical blue color, which can be applied in rapid and ultrasensitive detection of H2O2 visually.

3.
Mikrochim Acta ; 187(7): 422, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32617681

RESUMO

Four kinds of Ag3PO4 materials were prepared by controlling the experimental conditions, which were developed as oxidase mimics. Experimental results showed that different synthesis methods led to distinct crystal structures, morphologies, and surface properties, which contributed to diverse oxidase-like activities of Ag3PO4 materials. Among them, Ag3PO4 microcubes (APMCs) can efficiently catalyze the oxidation of colorless 3,3',5,5'-tetramethylbenzidine in the presence of dissolved oxygen to form a blue-colored oxide, presenting the best intrinsic oxidase mimetic ability. The higher-energy [110] facets with more oxygen vacancies exposed and more active sites coupled with more negative charge and larger specific surface area of APMCs contributed to its enhanced oxidase mimetic performance. Besides, mercury ions were proved to remarkably and selectively stimulate the oxidase-like ability of APMCs owing to the formation of Ag-Hg amalgam on its surface. Based on the stimulating effect of Hg2+ towards APMCs, a simple and rapid method for colorimetric determination of Hg2+ was thus established via the significant signal amplification and megascopic color variation. Under the optimal conditions, the sensing system showed a good linear relationship ranging from 0.1 to 7.0 µM and a detection limit of 20 nM for Hg2+, exhibiting high selectivity and good colour stability. Moreover, the colorimetric method was successfully applied to determine Hg2+ in real water samples. Considering these advantages, the developed colorimetric sensing system is expected to hold bright prospects for trace determination of Hg2+ in biological, environmental, and food samples. Graphical abstract The preparation process of Ag3PO4 materials and Hg2+-stimulated enhanced oxidase-like ability of Ag3PO4 microcubes in catalyzing the oxidation of TMB to generate a typical blue color, which can be applied in rapid and ultrasensitive detection of Hg2+ visually.

4.
Transplant Proc ; 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32718748

RESUMO

BACKGROUND: The number of pediatric deceased organ donors has recently declined, and the nonutilization of pediatric liver allografts has limited the development of liver transplantation. We determined the utilization rate of pediatric livers and identified risk factors for graft discard. METHODS: We used data from the Scientific Registry of Transplant Recipients database from January 1, 2000, to December 31, 2012. The trends of pediatric liver donors and utilization rates were analyzed. Donor risk factors that impacted the graft use of pediatric livers were measured. Logistic regression modelling was performed to evaluate graft utilization and risk factors. RESULTS: A total of 11,934 eligible pediatric liver donors were identified during this period. A total of 1191 authorized liver grafts did not recover or recovered without transplantation. Factors including pediatric donors >1 year of age (odds ratio [OR] = 2.956, 95% confidence interval [CI] 2.494-3.503, P < .001), nonhead trauma (OR = 2.243, 95% CI 1.903-2.642, P < .001), lack of heartbeat (OR = 7.534, 95% CI 5.899-9.623, P < .001), hepatitis B surface antigen positivity (OR = 4.588, 95% CI 1.021-20.625, P = .047), anti-hepatitis C virus positivity (OR = 4.691, 95% CI 1.352-16.280, P = .015), total bilirubin >1 mg/dL (OR = 1.743, 95% CI 1.469-2.068, P < .001), and blood urea nitrogen >21 mg/dL (OR = 1.941, 95% CI 1.546-2.436, P < .001) were significantly related to graft nonutilization. Steroids or diuretics administered prerecovery were significantly related to graft utilization (OR = 0.684, 95% CI 0.581-0.806, P < .001; OR = 0.744, 95% CI 0.634-0.874, P < .001; respectively). CONCLUSIONS: The pediatric liver allograft utilization rate and risk factors for nonutilization of grafts were determined.

5.
Aging (Albany NY) ; 122020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32692718

RESUMO

In this study, we investigated the mechanistic role of the long non-coding RNA (lncRNA) AC092171.4 in hepatocellular carcinoma (HCC). AC092171.4 was significantly upregulated in HCC tumor tissues compared to normal liver tissues. HCC patients with high AC092171.4 expression showed poorer overall survival (OS) and disease-free survival (DFS) than those with low AC092171.4 expression. In vitro cell proliferation, migration and invasiveness were all higher in AC092171.4-overexpressing HCC cells, but lower in AC092171.4-silenced HCC cells, than in controls. Balb/c nude mice injected with AC092171.4-silenced HCC cells had smaller xenograft tumors, which showed less growth and pulmonary metastasis than control tumors. Bioinformatics analyses and dual luciferase reporter assays confirmed that AC092171.4 binds directly to miR-1271, which targets the 3'UTR of GRB2 mRNA. AC092171.4 expression correlates negatively with miR1271 expression and correlates positively with GRB2 mRNA expression in HCC tissues from patients. HCC cells co-transfected with miR-1271 mimics and sh-AC092171.4 show less proliferation, migration, invasiveness, GRB2 protein, and epithelial to mesencyhmal transition (EMT) than sh-AC092171.4-transfected HCC cells. These findings demonstrate that AC092171.4 promotes growth and progression of HCC by sponging miR-1271 and upregulating GRB2. This makes AC092171.4 a potential prognostic indicator and therapeutic target for HCC patients.

6.
Liver Transpl ; 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32542994

RESUMO

It has been shown that normothermic machine perfusion (NMP), a novel preservation method, is able to assess and resuscitate liver grafts with risk factors. However, there is no consistent criteria for assessment of liver graft with NMP. Ischemia-free liver transplantation (IFLT) includes innovative surgical techniques and NMP, which can protect liver grafts from ischemia throughout organ procurement, preservation and implantation. In our center, 28 human livers from donation after brain death (DBD) were subjected to IFLT between July 2017 and October 2018. Correlation between post-transplant liver function tests with the perfusion parameters, blood gas analysis of perfusate and bile biochemistry were analyzed. During preservation phase, the vascular flow was stable and the lactate level decreased rapidly. The transaminase release in the perfusate was stably low, while the glucose level maintained a high level. The perfusate lactate and aspartate aminotransferase (AST) levels at one hour of perfusion were correlated with the post-transplant peak AST level. There were negative correlations between the portal vein/hepatic artery flow at the end of perfusion and the peak transaminase levels within 7 days post-transplantation. In conclusion, during IFLT, NMP is able to bridge the liver grafts from donors to recipients and can allow the assessment of liver function by perfusion characteristics.

7.
Mar Pollut Bull ; 152: 110885, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32479275

RESUMO

Microplastics are ubiquitous in our environment, yet we have little knowledge on their accumulation profile and changing trend. In this study, we selected the semi-enclosed Jiaozhou Bay as the research area to study the vertical distribution characteristics of microplastic in the sediment and analyzed factors that might affect this distribution pattern. We found six different polymer types and the microplastic abundance ranged between 2.5 items/kg d.w.-27.5 items/kg d.w.. Microplastic abundance was very low in deep sediment and generally showed a decreasing trend from the surface down with some shifts at different depth at certain sites. Based on our data, the total microplastics in the sediment were estimated to reach 3.71 tons in Jiaozhou Bay. This study shows that the vertical microplastic abundance profile in the sediment can not only show the microplastics pollution level but also reflect environmental factors and anthropogenic impacts.


Assuntos
Plásticos , Poluentes Químicos da Água/análise , Baías , Monitoramento Ambiental , Microplásticos
8.
Arch Oral Biol ; 117: 104769, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32599516

RESUMO

OBJECTIVE: This study aims to determine if low-intensity pulsed ultrasound (LIPUS) activates autophagy in human periodontal ligament cells (PDLCs) irrespective of lipopolysaccharide. DESIGN: Six groups were designed: control, LIPUS, lipopolysaccharide, LIPUS + lipopolysaccharide, LIPUS+3-Methyladenine, LIPUS + lipopolysaccharide+3-Methyl- adenine. LIPUS pretreated PDLCs for 2 h and lipopolysaccharide treated for different times. Real-time PCR and Western-blot were performed to evaluate mRNA and protein expression levels of autophagic genes Beclin-1 and LC3 respectively. A transmission electronic microscope was used to observe the autophagosome. ELISA was used to test interleukin-6 expression. RESULTS: Compared with the non-treatment, LIPUS pretreatment increased mRNA expression levels of LC3 (P < 0.05) and Beclin-1 (P < 0.05) at 4 h and 8 h, and enhanced the protein expression levels of LC3-Ⅱ at 8 h (P<0.05) and Beclin-1 at 4 h, 8 h and 16 h(P<0.05). After LIPUS pretreatment and lipopolysaccharide treatment for 8 h, LC3-Ⅱ and Beclin-1 protein expression levels were elevated (P < 0.05) compared with the control. Following further treatment by 3-Methyladenine, Beclin-1 protein expression was decreased (P < 0.05) compared with the LIPUS plus lipopolysaccharide group, but LC3-Ⅱ protein expression was not. Autophagosomes were not found in the LIPUS+3-Methyladenine and LIPUS+lipopolysaccharide+3-Methyladenine groups. After LIPUS pretreatment and lipopolysaccharide treatment for 36 h, intreleukin-6 expression was decreased (P<0.05) compared with the lipopolysaccharide group. However, after addition of 3-Methyladenine, intreleukin-6 expression was elevated (P < 0.05) compared with the LIPUS +lipopolysaccharide group. CONCLUSIONS: LIPUS can promote autophagy in PDLCs irrespective of lipopolysaccharide. Autophagy might be involved in LIPUS anti-inflammatory mechanism in PDLCS.

9.
Sci Total Environ ; 734: 139219, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32450395

RESUMO

In this study, the interaction of emerging pollutant polyvinyl chloride microplastics (PVC MPs) and human serum albumin (HSA) was investigated by fluorescence spectroscopy, UV-visible (UV-vis) absorption spectroscopy, circular dichroism (CD), and Fourier transform infrared (FT-IR) spectroscopy under simulated physiological conditions. Fluorescence results showed that PVC MPs (about 5000 nm in size) can effectively quench the intrinsic fluorescence of HSA through static quenching owing to the formation of HSA-PVC complex. The binding constants (Ka) between PVC and HSA at different temperatures were calculated as 4.97 × 103 M-1, 3.46 × 103 M-1 and 2.51 × 103 M-1, respectively. The number of binding sites was 1.26. The enthalpy change (ΔH), entropy change (ΔS) and free energy change (ΔG) were calculated to be -59.27 kJ·mol-1, 70.76 J·mol-1 K-1 and - 80.35 kJ·mol-1, respectively, indicating that the interaction of PVC with HSA was mainly driven by electrostatic forces. Moreover, results of UV-vis, FT-IR and CD further demonstrated that the microenvironment and secondary structure of HSA were changed a lot induced by PVC, leading to a decrease in α-helix. This work not only provides an insight into the intermolecular interaction between PVC and HSA, but also elucidates the potential biological toxicity of MPs at a molecular level.


Assuntos
Cloreto de Polivinila/química , Humanos , Microplásticos , Ligação Proteica , Albumina Sérica Humana , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 239: 118499, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32470815

RESUMO

In this paper, nanoparticles decorated Ce2(WO4)3 nanosheets (CWNSs) with negative potential and large specific surface area were synthesized and developed as highly efficient peroxidase mimics for colorimetric detection of H2O2. CWNSs can efficiently catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2 to induce an obvious color variation. Kinetic analysis indicated that the catalytic behaviors of CWNSs obey the typical Michaelis-Menten mechanism. The peroxidase-like catalytic mechanism of CWNSs was proposed according to the active species trapping experiments, verifying that ·O2- radicals played primary roles in the catalytic reaction. Based on the strong and stable peroxidase-like catalytic activity of CWNSs, a simple, rapid, selective, and ultrasensitive method was successfully established for colorimetric detection of H2O2. The method has a good linear response ranging from 0.5 µM to 100 µM for H2O2 concentration with a lower detection limit of 0.15 µM. Benefitting from the sensitive response and good stability, the method is applied in real sample detection and shows a favorable reproducibility and feasibility. This work not only provides a novel enzymatic mimics with remarkable catalytic activities for biomedical and environmental analysis, but also extends the application area of Ce2(WO4)3 materials.

11.
BMJ Open ; 10(5): e035374, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32376754

RESUMO

INTRODUCTION: During conventional liver transplantation (CLT), ischaemia-reperfusion injury (IRI) is inevitable and is associated with complications such as early allograft dysfunction (EAD), primary non-function and ischaemic-type biliary lesions. We have established a novel procedure called ischaemia-free liver transplantation (IFLT). The results from a pilot study suggest that IFLT might prevent IRI and yield better transplant outcomes than CLT. The purpose of this study was to further assess the efficacy and safety of IFLT versus CLT in patients with end-stage liver disease. METHODS AND ANALYSIS: This is an investigator-initiated, open-label, phase III, prospective, single-centre randomised controlled trial on the effects of IFLT in patients with end-stage liver disease. Adult patients (aged 18-75 years) eligible for liver transplantation will be screened for participation in this trial and will be randomised between the IFLT group (n=34) and the CLT group (n=34). In the IFLT group, the donor liver will be procured, preserved and implanted with continuous normothermic machine perfusion (NMP). In the CLT group, the donor liver will be procured after a fast cold flush, preserved in 0°C-4°C solution and implanted under hypothermic and hypoxic conditions. Patients in both groups will be managed according to the standard protocol of our centre. The primary end point is the incidence of EAD after liver transplantation. Intraoperative and postoperative parameters of donor livers and recipients will be observed and recorded, and postoperative liver graft function, complications and recipient and graft survival will be evaluated. After a 12-month follow-up of the last enrolled recipient, the outcomes will be analysed to evaluate the safety and efficacy of IFLT versus CLT in patients with end-stage liver disease. ETHICS AND DISSEMINATION: The protocol was reviewed and approved by the Ethics Committee of The First Affiliated Hospital of Sun Yat-sen University. The findings will be disseminated to the public through conference presentations and peer-reviewed scientific journals. TRIAL REGISTRATION NUMBER: ChiCTR1900021158.

12.
Food Chem ; 327: 127033, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32464459

RESUMO

Some varieties of edible mushrooms can accumulate high contents of arsenic, which is a public health concern. In this study, we developed a high-performance liquid chromatography method linked to inductively coupled plasma triple quadrupole mass spectrometry (HPLC-ICP-MS/MS) for sensitive and accurate determination of arsenite, arsenate, monomethylarsonic acid, dimethylarsinic acid, arsenocholine and arsenobetaine in edible mushrooms. The six arsenic species were extracted ultrasonically from mushrooms using ultrapure water at 60 °C as the solvent, separated on a PRP-X100 anion exchange column (4.1 × 250 mm, 10 µm), with 20 mmol/L NH4HCO3 and 50 mmol/L (NH4)2CO3 as the mobile phase, and quantified using ICP-MS/MS in the oxygen reaction mode. The linear range of the method was 0.5 µg/L-100 µg/L with detection and quantification limits of 2.5 µg/kg-10 µg/kg (S/N = 3), and 8 µg/kg-33 µg/kg (S/N = 10), respectively. This method was applied successfully to the detection and speciation of arsenic in eight varieties (266 samples) of mushrooms. Our results indicated that most wild edible mushrooms contained organic arsenic, mainly arsenobetaine and arsenocholine. However, the inorganic arsenic content of Armillariella tabescens (3.63 mg/kg) and parts of the cultivated Agaricus blazei murrill (up to 4.50 mg/kg) were relatively high, which is potential risk to the health of consumers.

13.
Sci Total Environ ; 727: 138458, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32339827

RESUMO

Low-molecular-weight organic acids (LMWOAs) are ubiquitous water-soluble organic compounds with mass production worldwide, but their influence on coastal marine environments is still lack of consideration. In this study, we select a typical nearshore bay - the Jiaozhou Bay, which is surrounded by Qingdao - a city with modern manufacture, agriculture, aquaculture and service industry, as study area, to investigate the effect of LMWOAs on the nearshore marine environment, and their impact on seawater acidification in coastal areas. During Sep. 2016 to Aug. 2017, we identified three different LMWOAs - acetic acid (AA), formic acid (FA) and lactic acid (LA), with average concentrations of 46.7, 13.9 and 1.4 µmol·L-1 in the seawater of the bay, respectively. Due to the establishment of the Jiaozhou Bay Bridge, the seawater exchange capacity was weakened and thereby the concentration and stocks of AA and FA increased. As weak acids in seawater, the influence of LMWOAs on the seawater acidification of the Jiaozhou Bay was investigated. LMWOAs had significant impact on seawater pH and every 10 µmol·L-1 LMWOA caused an average of 0.02 pH unit decrease. From 2010 to 2017, pH value in the seawater of the bay decreased by about 0.103 and LMWOAs contributed about 83% of its decrease. Besides, two models were established to estimate the influence of LMWOAs on the seawater pH by applying the data set of dissolved inorganic carbon (DIC), total alkalinity (TA) and LMWOAs. The results showed that LMWOAs could enhance acidification of coastal seawater. Considering the importance of LMWOAs in seawater, it is necessary to evaluate their future changes in coastal marine environments. This study initiated a way to identify the source of LMWOAs in seawater and to evaluate their contribution to seawater acidification, and also provided a series of dataset for future study on LMWOAs in coastal environment.

14.
Nano Lett ; 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32283937

RESUMO

The further improvement of sodium ion batteries requires the elucidation of the mechanisms pertaining to reversibility, which allows the novel design of the electrode structure. Here, through a hydrogel-embedding method, we are able to confine the growth of few-layer SnS2 nanosheets between a nitrogen- and sulfur-doped carbon nanotube (NS-CNT) and amorphous carbon. The obtained carbon-sandwiched SnS2 nanosheets demonstrate excellent sodium storage properties. In operando small-angle X-ray scattering combined with the ex situ X-ray absorption near edge spectra reveal that the redox reactions between SnS2/NS-CNT and the sodium ion are highly reversible. On the contrary, the nanostructure evolution is found to be irreversible, in which the SnS2 nanosheets collapse, followed by the regeneration of SnS2 nanoparticles. This work provides operando insights into the chemical environment evolution and structure change of SnS2-based anodes, elucidating its reversible reaction mechanism, and illustrates the significance of engineered carbon support in ensuring the electrode structure stability.

15.
Ann Transplant ; 25: e921529, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32312947

RESUMO

BACKGROUND Normothermic machine perfusion (NMP) can provide access to evaluate and resuscitate high-risk donor livers before transplantation. The purpose of this study was to determine the efficacy of NMP in preservation and assessment of extended-criteria donor (ECD) livers in China. CASE REPORT From September 2018 to March 2019, 4 liver grafts from 3 transplant center defined as ECD were subjected to NMP, and then were transplanted successfully. During perfusion, perfusion parameters such as vascular flow, glucose level, lactate clearance, and bile production/composition were recorded to assess graft viability. All recipients were followed up 6 months after transplantation. CONCLUSIONS NMP provides a potential tool for preservation and assessment of ECD livers in China.

16.
ACS Sens ; 5(5): 1381-1388, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32314571

RESUMO

Here, a portable and accurate phosphate sensor using a gradient Fabry-Pérot array (FPA) is proposed. It can form a bidirectional gradient concentration (absorbance) distribution in the gradient FPA, simplifying the complex operations to get a standard curve and saving time. The gradient FPA can effectively filter out the interference (bubbles, light intensity, and salinity) while improving the absorbance, achieving a highly accurate and stable detection. Besides, the smartphone simplifies data processing and makes sensors more portable. In this work, the detection errors of standard solutions (100, 50, and 30 µM) are 0.39, 1.48, and 1.84%, respectively, and it has also been demonstrated with errors of 2.46 (sample 1, seawater), 2.08 (sample 2, lake water), and 1.83% (sample 3, sewage) for natural samples detection, which is more accurate than a traditional analyzer. The sensor has a good performance when affected by bubbles, light intensity, and salinity. In addition, the detection time is shortened to 80 s, which is more time saving compared with traditional devices, and the limit of detection (LOD) is 0.4 µM. It can be predicted that the novel optofluidic sensor is conducive to build a smart nutrient monitoring system and will be applied in the field of biochemistry and environmental chemistry.

17.
BMC Musculoskelet Disord ; 21(1): 238, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32284058

RESUMO

BACKGROUND: Percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) are widely used in the treatment of Kümmell's disease. The purpose of this article is to investigate the clinical efficacy of PVP and PKP for Kümmell's disease. METHODS: The clinical data that 56 cases of Kümmell's disease treated with either PVP (28 cases) or PKP (28 cases) from December 2015 to December 2017 were prospectively analyzed. Gender, age, course of disease, injury segment, bone mineral density (BMD), visual analogue scale (VAS), Oswestry disability index (ODI), imaging measurement indexes before surgery between the two groups showed no significant difference (all P > 0.05). The bone cement leakage rate, bone cement injection amount, operation time, VAS, ODI, the rate of vertebral compression, correction rate of kyphosis and refracture rate of adjacent vertebra in 2 years were compared between the two groups to calculate clinical efficacy. RESULTS: The two groups were followed up for 24-48 months. There was no significant difference in the follow-up time, amount of bone cement injected, incidence of bone cement leakage and refracture rate of adjacent vertebrae between the two groups (all P > 0.05). The operation time, intraoperative blood loss and fluoroscopy times of the PVP group were significantly lower than those of the PKP group (all P = 0.000). VAS score and ODI of the two groups were significantly lower at 1 day, 1 year and 2 years after surgery than before surgery (all P < 0.05), but there was not statistically significant difference between the two groups at each time point after surgery (all P > 0.05). The rate of vertebral compression and kyphosis correction in the two groups were significantly corrected (P < 0.05, respectively) and decreased significantly with time (all P < 0.05), But there was not significant difference between the two groups at any time point (all P > 0.05). CONCLUSION: Both PVP and PKP can achieve similar effects in the treatment of Kümmell's disease. Because the cost, operation time, blood loss, radiation exposure and surgical procedure of PVP are less than those of PKP, PVP has more clinical priority value.

18.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(4): 441-444, 2020 Apr 10.
Artigo em Chinês | MEDLINE | ID: mdl-32219832

RESUMO

OBJECTIVE: To detect pathological variant in two patients with Chediak-Higashi syndrome (CHS) from a consanguineous family and to explore its genotype-phenotype correlation. METHODS: Clinical data was collected for this pedigree. Genomic DNA was prepared from probands' peripheral leukocytes and their relatives' fingernail. Whole exome sequencing and Sanger sequencing were carried out to detect potential variant of the LYST gene. RESULTS: The proband presented with partial oculocutaneous albinism, immunodeficiency and acidophilic inclusion body in bone marrow and blood smears. A novel homozygous nonsense variant c.8782C>T (p.Gln2928*) was identified in exon 34 of the LYST gene in the sib pair. The same variant was found to be in heterozygous status in 6 unaffected individuals from the pedigree. CONCLUSION: Above result enriched the mutational spectrum of CHS and provided a basis for genetic counseling and prenatal diagnosis for this pedigree.


Assuntos
Síndrome de Chediak-Higashi/genética , Linhagem , Proteínas de Transporte Vesicular/genética , Éxons , Heterozigoto , Humanos , Mutação , Análise de Sequência de DNA , Sequenciamento Completo do Exoma
19.
Artigo em Inglês | MEDLINE | ID: mdl-32129595

RESUMO

Doping chemistry has been regarded as an efficient strategy to overcome some fundamental challenges facing the "no-cobalt" LiNiO2 cathode materials. By utilizing the doping chemistry, we evaluate the battery performance and structural/chemical reversibility of a new no-cobalt cathode material (Mg/Mn-LiNiO2). The unique dual dopants drive Mg and Mn to occupy the Li site and Ni site, respectively. The Mg/Mn-LiNiO2 cathode delivers smooth voltage profiles, enhanced structural stability, elevated self-discharge resistance, and inhibited nickel dissolution. As a result, the Mg/Mn-LiNiO2 cathode enables improved cycling stability in lithium metal batteries with the conventional carbonate electrolyte: 80% capacity retention after 350 cycles at C/3, and 67% capacity retention after 500 cycles at 2C (22 °C). We then take the Mg/Mn-LiNiO2 as the platform to investigate the local structural and chemical reversibility, where we identify that the irreversibility takes place starting from the very first cycle. The highly reactive surface induces the surface oxygen loss, metal reduction reaching the subsurface, and metal dissolution. Our data demonstrate that the dual dopants can, to some degree, mitigate the irreversibility and improve the cycling stability of LiNiO2, but more efforts are needed to eliminate the key challenges of these materials for battery operation in the conventional carbonate electrolyte.

20.
J Am Chem Soc ; 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32119535

RESUMO

Non-platinum group metal (non-PGM) electrocatalysts for the oxygen reduction reaction (ORR) are generally composed of iron, nitrogen, and carbon synthesized through high-temperature pyrolysis. Among the various types of precursors, metal-organic frameworks (MOFs), zeolitic imidazolate framework (ZIF)-8 in particular, have often been used in the synthesis. The pyrolysis of ZIF-8 precursor relies on the use of Zn as a sacrificial metal (SM), and the optimal processing temperatures often exceed 1000 °C to generate active non-PGM catalysts. The high pyrolysis temperature tends to result in heterogeneous active moieties ranging from Fe single atoms to nanoparticles. In this study, we present the synthesis of non-PGM catalysts using Cd as the sacrificial metal instead of Zn. By using Cd, we were able to generate active non-PGM electrocatalysts from the MOF precursors at a low pyrolysis temperature of 750 °C, which helps preserve the single atomic iron active sites.

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