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1.
Chemosphere ; 244: 125568, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050347

RESUMO

Persulfate (PS) is widely used for environmental remediation, but its organic contaminant removal performance strongly depends on its activation. In this study, we demonstrate that pyrite (FeS2) can more effectively activate PS than the commonly used FeSO4 for atrazine degradation. When 3.0 mM of PS and 4.2 mM of iron salts were used, the atrazine degradation efficiency of FeS2/PS was 1.4 times that of FeSO4/PS, while the amount of consumed PS in case of FeS2 was only 53% of that by FeSO4. The better PS activation performance of FeS2 could be attributed to its slow and sustainable release of dissolved Fe(II), inhibiting the quenching reaction between •SO4-/•OH and Fe(II) ions, and thus producing more reactive oxygen species for the atrazine degradation. More importantly, the surface bound Fe(II) of FeS2 could activate molecular oxygen to generate superoxide radical (•O2-), which could further promote the effective decomposition of PS by accelerating the Fe(III)/Fe(II) redox cycle. This study unravels the roles of dissolved Fe(II) and surface bound Fe(II) on the persulfate activation, and provides a promising heterogeneous persulfate activator for pollutant control and environmental remediation.


Assuntos
Atrazina/química , Ferro/química , Sulfetos/química , Poluentes Químicos da Água/química , Compostos Benzidrílicos , Compostos Férricos , Oxirredução , Sulfatos , Poluentes Químicos da Água/análise
2.
Artigo em Inglês | MEDLINE | ID: mdl-32052925

RESUMO

Warfarin is a narrow therapeutic index anticoagulant drug, and several generic formulations have been approved worldwide. However, there has been no report evaluating the bioequivalence of warfarin sodium according to US Food and Drug Administration draft guidance. We designed a 2-sequence and 4-period crossover study to compare the pharmacokinetic profile and assess bioequivalence between the test warfarin sodium tablet and reference product Coumadin (2.5 mg) in 56 healthy Chinese subjects under fasting and fed conditions. The plasma concentration of warfarin was analyzed by a validated liquid chromatography-tandem mass spectrometry assay, and the reference-scaled procedure was used to determine bioequivalence for the pharmacokinetics parameters. The results showed that the point estimate of geometric mean ratios of Cmax and AUC0-t for warfarin were 103.21% and 99.31%, respectively, in the fasting condition and 100.62% and 98.98%, respectively, in the fed condition, and the 90% confidence intervals were all within the range of 90.00%-111.11%. The upper limit of the 90% confidence interval of estimated within-subject variation ratios of the test and reference products was 1.33 for Cmax and 2.22 for AUC0-t under the fasting condition and 1.68 for Cmax and 2.15 for AUC0-t under the fed condition. Overall, bioequivalence of the 2 warfarin sodium products was demonstrated.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31931575

RESUMO

Stabilized Cu+ species have been widely considered as catalytic active sites in composite copper catalysts for catalytic reactions with industrial importance. However, few examples comprehensively explicated the origin of stabilized Cu+ in a low-cost and widely investigated CuO/TiO2 system. In this study, mass producible CuO/TiO2 catalysts with interface-stabilized Cu+ were prepared, which showed excellent low-temperature CO oxidation activity. A thorough characterization and theoretical calculations proved that the strong charge-transfer effect and Ti-O-Cu hybridization in Ti-doped CuO(111) at the CuO/TiO2 interface contributed to the formation and stabilization of Cu+ species. The CO molecule adsorbed on Cu+ and reacted directly with Ti doping-promoted active lattice oxygen via a Mars-van Krevelen mechanism, leading to the enhanced low-temperature activity.

4.
Mol Biol Cell ; 31(6): 439-451, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31967944

RESUMO

The large GTPase Dynamin 2 (Dyn2) is known to increase the invasiveness of pancreatic cancer tumor cells, but the mechanisms by which Dyn2 regulates changes in the actin cytoskeleton to drive cell migration are still unclear. Here we report that a direct interaction between Dyn2 and the actin-bundling protein alpha-actinin (α-actinin) 4 is critical for tumor cell migration and remodeling of the extracellular matrix in pancreatic ductal adenocarcinoma (PDAC) cells. The direct interaction is mediated through the C-terminal tails of both Dyn2 and α-actinin 4, and these proteins interact at invasive structures at the plasma membrane. While Dyn2 binds directly to both α-actinin 1 and α-actinin 4, only the interaction with α-actinin 4 is required to promote tumor cell invasion. Specific disruption of the Dyn2-α-actinin 4 interaction blocks the ability of PDAC cells to migrate in either two dimensions or invade through extracellular matrix as a result of impaired invadopodia stability. Analysis of human PDAC tumor tissue additionally reveals that elevated α-actinin 4 or Dyn2 expression are predictive of poor survival. Overall, these data demonstrate that Dyn2 regulates cytoskeletal dynamics, in part, by interacting with the actin-binding protein α-actinin 4 during tumor cell invasion.

5.
J Clin Invest ; 130(1): 189-202, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31550238

RESUMO

Currently, an effective targeted therapy for pancreatitis is lacking. Hereditary pancreatitis (HP) is a heritable, autosomal-dominant disorder with recurrent acute pancreatitis (AP) progressing to chronic pancreatitis (CP) and a markedly increased risk of pancreatic cancer. In 1996, mutations in PRSS1 were linked to the development of HP. Here, we developed a mouse model by inserting a full-length human PRSS1R122H gene, the most commonly mutated gene in human HP, into mice. Expression of PRSS1R122H protein in the pancreas markedly increased stress signaling pathways and exacerbated AP. After the attack of AP, all PRSS1R122H mice had disease progression to CP, with similar histologic features as those observed in human HP. By comparing PRSS1R122H mice with PRSS1WT mice, as well as enzymatically inactivated Dead-PRSS1R122H mice, we unraveled that increased trypsin activity is the mechanism for R122H mutation to sensitize mice to the development of pancreatitis. We further discovered that trypsin inhibition, in combination with anticoagulation therapy, synergistically prevented progression to CP in PRSS1R122H mice. These animal models help us better understand the complex nature of this disease and provide powerful tools for developing and testing novel therapeutics for human pancreatitis.

6.
Chemosphere ; 238: 124598, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31446276

RESUMO

Sewage sludge dewatering is an efficient approach to reduce the volume of sludge for the subsequent disposal. In this study, a novel one-step acidification sludge dewatering method was developed with using oxalic acid as a conditioner. In laboratory-scale experiments with the dosage of 200 mg/g dry solid (DS), the normalized capillary suction time and the specific resistance to filtration were respectively decreased by 78.7% and 60.0% after 30 min of oxalic acid conditioning, much more efficient than those conditioned with sulfuric acid and hydrochloric acid at the same pH value. This superior dewatering performance was attributed to two factors. One was that oxalic acid could more efficiently promote the hydrolysis of polysaccharide, especially pectins, to release bound water. The other was that OA could dissolve more Fe3+ and Al3+, as well as form precipitate with Ca2+ in sludge, which may act as flocculants or co-precipitator for the subsequent sludge particles coagulation. In pilot-scale experiments, the water content of oxalic acid conditioned sludge cake was reduced to 60% under the optimum conditions, while the reagent cost was as low as 110.0 USD/t DS. This work provides a cost-effective and easy-operated sewage sludge disposal technique, and also sheds light on the potential of oxalic acid in environmental waste treatment.


Assuntos
Dessecação/métodos , Ácido Oxálico/química , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Filtração , Floculação , Ácido Clorídrico/química , Concentração de Íons de Hidrogênio , Hidrólise , Polissacarídeos/metabolismo , Ácidos Sulfúricos/química , Água/química
7.
J Hazard Mater ; : 121730, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31784137

RESUMO

Developing efficient methods to degrade perfluorochemicals (PFCs), an emerging class of highly recalcitrant contaminants, are urgently needed in recent years, due to their persistence, high toxicity, and resistance to most regular treatment procedures. Here, a UV-photolysis system is reported for efficient mineralization of perfluorooctanoic acid (PFOA) via irradiation of ferric nitrate aqueous solution, where in-situ generating •NO2 and the effective Fe3+/Fe2+ redox cycle synergistically play great roles on rapidly mediating the mineralization of PFOA. A fast PFOA removal kinetics with first-order kinetic constants of 2.262 h-1 is observed at initial PFOA concentration of 5 ppm (50 mL volume), reaching ∼ 92 % removal efficiency within only 0.5-h irradiation. Near-stoichiometric fluoride ions liberation and high total organic carbon (TOC) removal efficiency (∼100 %) further validated the capability for completely destructive removal of PFOA. A tentative pathway for PFOA destruction is proposed. This work, by UV photolysis of abundant existing iron/nitrate-based systems in natural environment, provides an economical, sustainable and highly efficient approach for complete mineralization of perfluorinated chemicals.

8.
Pancreatology ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31831392

RESUMO

BACKGROUND & OBJECTIVES: Biomarkers are increasingly required to molecularly characterize pancreatic ductal adenocarcinoma (PDAC) subgroup populations, to determine who may benefit from immune based targeted therapy. We evaluated the feasibility of gene expression signature detection and the respective landscape of specific tumor infiltrating lymphocytes (TILs), cancer/testis (CT) antigens, and immune checkpoints for possible future personalized immunotherapy eligibility. METHODS: Dedicated digital mRNA oncologic immune profiling of 770 genes using a Nanostring nCounter® PanCancer Immune Profiling Panel was performed using archived endoscopic ultrasound fine needle biopsy (EUS FNB) PDAC specimens as a case series in a tertiary care setting. RESULTS: The spectrum of mRNA gene expression within the tumor specimens revealed that 44.8%, 10.0% and 50.7% of evaluated genes had a ≥ 2-fold increase, a ≤ 2-fold reduction or between <2 and >2 change of mRNA expression, when compared to normal controls. The corresponding landscape of TILs, CT antigens, and immune checkpoints highlighted several possibilities that could potentially be amenable to targeted personalized immunotherapy. This includes members of the Tumor Associated Macrophage family (CD68, CXCL5, and MARCO), members of the CT antigen family (PRAME, TTK and PBK) and the "second generation" checkpoints TIM3 and BTLA. CONCLUSIONS: Our study represents the ability to successfully perform digital mRNA expression profile analyses to immunophenotype PDAC EUS FNB specimens by evaluating the expression of >730 genes within the tumor immune microenvironment. This may facilitate the search for novel therapeutic targets, offering the opportunity to go beyond immune monotherapy, but perhaps to use combined immunomodulatory agents.

9.
Hum Pathol ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31698005

RESUMO

Patients with inflammatory bowel disease (IBD) may occasionally present with lymphocytic colitis/collagenous colitis (LC/CC) either before or after the onset of IBD. Although a few reports have described a small number of such cases, the relationship between these 2 disorders is still unclear. We evaluated 27 patients with diagnosis of either ulcerative colitis (UC) or Crohn disease (CD) and LC/CC. Clinical, endoscopic, and pathological features were reviewed. Ten patients with initial diagnoses of LC (n = 2)/CC (n = 8) evolved into UC (n = 7) or CD (n = 3) after a median interval of 14 months (range, 2-44 months). Among these, 4 patients with LC/CC evolving into IBD also had recurrent CC in a quiescent phase of IBD. Seventeen patients with initial diagnosis of UC (n = 11) or CD (n = 6) developed LC (n = 6)/CC (n = 11) after a median interval of 108 months (range, 15-548 months). IBD patients with initial presentation of LC/CC were significantly older than those who developed LC/CC after onset of IBD (66.5 versus 34.0 years old, P = .001). The interval time between LC/CC to IBD was significantly shorter than that of IBD to LC/CC (14 versus 108 months, P = .007). Quiescent UC with superimposed CC was the most common pattern (n = 8). Patients with CD had shorter interval time to develop LC/CC than UC patients, although it was not statistically significant (60.5 versus 139 months, P = .14). Endoscopically, most patients that started with LC/CC had unremarkable findings, but 11 of 17 patients who developed LC/CC after IBD showed quiescent chronic colitis. Histologically, LC/CC patients with diagnosis of IBD, either before or after, more frequently show active inflammation. Chronicity was more commonly seen in biopsy of LC/CC patients with a history of IBD. Our study found that IBD patients with initial presentation of LC/CC tend to occur in older age, with shorter interval time and frequent active inflammation in initial LC/CC. These findings suggest that LC/CC may be a spectrum of IBD as the initial presentation in a subset of older IBD patients. On the other hand, IBD patients can develop LC/CC associated with chronic mucosal injury many years after the onset of IBD (typically with >10 years interval time while patients are in remission phase), for which these 2 processes seem unrelated to each other.

10.
J Biol Chem ; 294(52): 19844-19851, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31735710

RESUMO

Type I interferon (IFN) induced by virus infections during pregnancy can cause placental damage, but the mechanisms and identities of IFN-stimulated genes that are involved in this damage remain under investigation. The IFN-induced transmembrane proteins (IFITMs) inhibit virus infections by preventing virus membrane fusion with cells and by inhibiting fusion of infected cells (syncytialization). Fusion of placental trophoblasts via expression of endogenous retroviral fusogens known as syncytins forms the syncytiotrophoblast, a multinucleated cell structure essential for fetal development. We found here that IFN blocks fusion of BeWo human placental trophoblasts. Stably expressed IFITM1, -2, and -3 also blocked fusion of these trophoblasts while making them more resistant to virus infections. Conversely, stable IFITM knockdowns in BeWo trophoblasts increased their spontaneous fusion and allowed fusion in the presence of IFN while also making the cells more susceptible to virus infection. We additionally found that exogenous expression of IFITMs in HEK293T cells blocked fusion with cells expressing syncytin-1 or syncytin-2, confirming the ability of IFITMs to block individual syncytin-mediated fusion. Overall, our data indicate that IFITMs inhibit trophoblast fusion and suggest that there may be a critical balance between these antifusogenic effects and the beneficial antiviral effects of IFITMs in virus infections during pregnancy.

11.
Indian J Pathol Microbiol ; 62(4): 586-588, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31611445

RESUMO

The follicular variant of peripheral T-cell lymphoma, not otherwise specified, is very rare. Primary epiglottic follicular variant of peripheral T-cell lymphoma is extremely rare in clinical practice. Here, we report the first case of a follicular variant of peripheral T-cell lymphoma not otherwise specified in a 44-year-old Chinese man, who presented with a tumor in the middle of the epiglottis tongue surface. Microscopically, the tumor had a vague nodular growth pattern and the morphology of the nodules was different from each other at low power. Atypical lymphoid cells were medium to large in size and had round nuclei, with an irregular nuclear membrane, distinct nucleoli, and rapid mitotic activity. Plasma cells were found surrounding the nodules. The tumor cells were positive for follicular helper T-cell markers (CD10, PD-1, CXCL13, and BCL-6). The EBER was negative by in situ hybridization. Polymerase chain reaction-based analysis showed monoclonal rearrangements of TCRß, TCRγ, and polyclonal rearrangements of IgH, IgK, and IgL. The clinical and imaging features and the prognostic factors of FV PTCL-NOS remain poorly understood. Thus, investigation of more cases and longer follow-up is necessary to understand the disease and to identify the best treatment to improve prognosis.


Assuntos
Epiglote/patologia , Linfoma Folicular/diagnóstico , Linfoma Folicular/patologia , Linfoma de Células T Periférico/diagnóstico , Linfoma de Células T Periférico/patologia , Adulto , Quimiocina CXCL13/genética , Epiglote/diagnóstico por imagem , Humanos , Masculino , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-6/genética , Linfócitos T/citologia , Tomografia Computadorizada por Raios X
12.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(10): 1203-1209, 2019 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-31544426

RESUMO

Objective: To summarize the evolving concept and research progress on stability reconstruction in the surgical treatment of intertrochanteric fracture. Methods: Related literature and author's own experience concerning the surgical treatment of intertrochanteric fracture were reviewed and analyzed in terms of fracture pathoanatomy, stable and unstable pattern, adequate and in-adequate reduction, primary and secondary stability, postoperative stability evaluation, and early weight-bearing. Results: Intertrochanteric fracture occur at the translational area of cervico-trochanteric junction, which has a nature tendency to varus instability. Fracture reduction quality is the paramount factor and is evaluated by two views, the anteroposterior and lateral Garden alignment and cortex apposition between the head-neck fragment and the femoral shaft. Rather than the posteromedial lesser trochanteric frag ment, the cortical support concept (positive, neutral, negative) emphasizes the reduction of anteromedial cortex to a nonanatomic positive apposition or an "anatomic" neutral apposition in intraoperative fluoroscopy. Postoperative radiographic stability score provides a quantitative assessment for early weight-bearing standing and walking. However, some fractures may lose cortical contact and buttress (negative) during the process of postoperative telescoping and secondary stability. Further studies are needed to elucidate the risk factors such as tilting, swing or rotation of the head-neck fragment, and propose new preventive methods. Conclusion: Stability reconstruction of intertrochanteric fracture requires adequate fracture reduction with Garden alignment and anteromedial cortical support apposition, and reliable sustainment by internal fixation implants. Early weight-bearing standing and walking is safe in patients with perfect postoperative stability score.


Assuntos
Fixação Interna de Fraturas , Fraturas do Quadril , Pinos Ortopédicos , Humanos , Estudos Retrospectivos , Resultado do Tratamento
13.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(10): 1228-1233, 2019 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-31544430

RESUMO

Objective: To measure the rotation angle of the head-neck fragment of intertrochanteric fracture after cephalomedullary nail fixation by three-dimensional CT imaging, and to explore its clinical significance. Methods: The clinical data of 68 patients with unstable intertrochanteric fracture of AO/Orthopaedic Trauma Association (AO-OTA) type 31-A2 treated with cephalomedullary nail fixation and with complete intraoperative fluoroscopy and postoperative three-dimensional CT imaging data between July 2016 and October 2018 were retrospectively analyzed. Among them, there were 21 males and 47 females, aged 68-93 years, with an average age of 81.8 years. There were 31 cases of AO/OTA type 31-A2.2 and 37 cases of 31-A2.3. Fracture reduction quality was evaluated according to Baumgaertner et al. and Chang et al. criteria. The anteromedial cortical contact or not of each patient was observed by three-dimensional CT imaging on T3DView software after operation. The rotation of head-neck fragments were divided into three types: non-rotation, flexion rotation, and hyperextension rotation. The rotation angles of each type were measured and the relationship between the rotation type of the head-neck fragments and the contact of the anteromedial cortex was analyzed. Results: The reduction and fixation of the small trochanter were not performed in 68 patients. According to Baumgaertner et al. criteria, the quality of fracture reduction was excellent in 15 cases (22.1%), acceptable in 50 cases (73.5%), and poor in 3 cases (4.4%). According to Chang et al. criteria, 31 cases were excellent (45.6%), 33 cases were acceptable (48.5%), and 4 cases were poor (5.9%). Thirty-nine cases (57.4%) received anteromedial cortical support and 29 cases (42.6%) did not receive cortical support. Three-dimensional CT imaging showed non-rotation in 12 cases (17.6%), flexion rotation in 39 cases (57.4%), and hyperextension rotation in 17 cases (25.0%). There were 7 cases (58.3%), 30 cases (76.9%), and 2 cases (11.8%) of cortical support in non-rotation group, flexion rotation group, and hyperextension rotation group, respectively. The rotation angles were (1.05±0.61), (13.96±6.17), (8.21±3.88)°, respectively. There were significant differences between groups ( P<0.05). Conclusion: In the unstable intertrochanteric fracture after cephalomedullary nail fixation, the rotation of head-neck fragment exists in most patients, and the types of flexion rotation and non-rotation can easily obtain cortical support reduction.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Quadril , Idoso , Idoso de 80 Anos ou mais , Pinos Ortopédicos , Feminino , Fêmur , Humanos , Masculino , Estudos Retrospectivos , Rotação , Resultado do Tratamento
14.
Ann Transl Med ; 7(16): 369, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31555683

RESUMO

Background: It has been reported that glucagon-like peptide-1 (GLP-1) can alleviate diabetic osteoporosis (DOP). This study was to investigate the effects of GLP-1RA liraglutide and dipeptidyl peptdase-4 (DPP-4) inhibitor vildagliptin on the advanced glycation end products (AGEs)-induced bone injury in ApoE-/- mice with euglycemia. Methods: The bone markers OC, PINP, PTH, TRACP and CTX, the mRNA and protein expressions of RAGE in the femur, and the femoral morphology index were determined to evaluate whether the osteoporosis was improved by liraglutide or vildagliptin. Results: AGEs adversely affected the bone metabolism, characterized by reduced OC and increased CTX. However, vildagliptin reduced AGEs and increased OC, and liraglutide significantly decreased AGEs and PTH. Both vildagliptin and liraglutide had no effects on the bone metrology and RAGE expression in the femurs of ApoE-/- mice. Conclusions: The elevated AGEs may exacerbate osteogenesis and increase bone resorption, and vildagliptin/liraglutide may improve bone metabolism.

15.
Proc Natl Acad Sci U S A ; 116(37): 18607-18612, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31451661

RESUMO

Influenza virus can disseminate from the lungs to the heart in severe infections and can induce cardiac pathology, but this has been difficult to study due to a lack of small animal models. In humans, polymorphisms in the gene encoding the antiviral restriction factor IFN-induced transmembrane protein 3 (IFITM3) are associated with susceptibility to severe influenza, but whether IFITM3 deficiencies contribute to cardiac dysfunction during infection is unclear. We show that IFITM3 deficiency in a new knockout (KO) mouse model increases weight loss and mortality following influenza virus infections. We investigated this enhanced pathogenesis with the A/PR/8/34 (H1N1) (PR8) influenza virus strain, which is lethal in KO mice even at low doses, and observed increased replication of virus in the lungs, spleens, and hearts of KO mice compared with wild-type (WT) mice. Infected IFITM3 KO mice developed aberrant cardiac electrical activity, including decreased heart rate and irregular, arrhythmic RR (interbeat) intervals, whereas WT mice exhibited a mild decrease in heart rate without irregular RR intervals. Cardiac electrical dysfunction in PR8-infected KO mice was accompanied by increased activation of fibrotic pathways and fibrotic lesions in the heart. Infection with a sublethal dose of a less virulent influenza virus strain (A/WSN/33 [H1N1]) resulted in a milder cardiac electrical dysfunction in KO mice that subsided as the mice recovered. Our findings reveal an essential role for IFITM3 in limiting influenza virus replication and pathogenesis in heart tissue and establish IFITM3 KO mice as a powerful model for studying mild and severe influenza virus-induced cardiac dysfunction.

16.
NMR Biomed ; 32(11): e4158, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31393647

RESUMO

We developed a novel manganese (Mn2+ ) chelate for magnetic resonance imaging (MRI) assessment of myocardial viability in acute and chronic myocardial infarct (MI) models, and compared it with Gadolinium-based delay enhancement MRI (Gd3+ -DEMRI) and histology. MI was induced in 14 rabbits by permanent occlusion of the left circumflex coronary artery. Gd3+ -DEMRI and Mn2+ chelate-based delayed enhancement MRI (Mn2+ chelate-DEMRI) were performed at 7 days (acute MI, n = 8) or 8 weeks (chronic MI, n = 6) after surgery with sequential injection of 0.15 mmol/kg Gd3+ and Mn2+ chelate. The biodistribution of Mn2+ in tissues and blood was measured at 1.5 and 24 h. Blood pressure, heart rate (HR), left ventricular (LV) function, and infarct fraction (IF) were analyzed, and IF was compared with the histology. The Mn2+ chelate group maintained a stable hemodynamic status during experiment. For acute and chronic MI, all rabbits survived without significant differences in HR or LV function before and after injection of Mn2+ chelate or Gd3+ (p > 0.05). Mn2+ chelate mainly accumulated in the kidney, liver, spleen, and heart at 1.5 h, with low tissue uptake and urine residue at 24 h after injection. In the acute MI group, there was no significant difference in IF between Mn2+ chelate-DEMRI and histology (22.92 ± 2.21% vs. 21.79 ± 2.25%, respectively, p = 0.87), while Gd3+ -DEMRI overestimated IF, as compared with histology (24.54 ± 1.73%, p = 0.04). In the chronic MI group, there was no significant difference in IF between the Mn2+ chelate-DEMRI, Gd3+ -DEMRI, and histology (29.50 ± 11.39%, 29.95 ± 9.40%, and 29.00 ± 10.44%, respectively, p > 0.05), and all three were well correlated (r = 0.92-0.96, p < 0.01). We conclude that the use of Mn2+ chelate-DEMRI is reliable for MI visualization and identifies acute MI more accurately than Gd3+ -DEMRI.

17.
Injury ; 50(11): 2108-2112, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31353093

RESUMO

OBJECTIVE: To introduce a new method for intraoperative detection of rotational malreduction of the lateral malleolus using conventional fluoroscopy. MATERIAL AND METHODS: From January 2014 to December 2017, 56 Weber type C unstable lateral malleolar fractures with syndesmosis injury were identified. The fibular fracture patterns were simple oblique or transverse in 20, comminuted in 25, and Maisonneuve injury with fibular neck fractures in 11 cases. 47 cases were operated with ORIF, and 9 cases of Maisonneuve fractures were operated with CRIF. The mortise view of the contralateral uninjured ankle was used for intraoperative comparison. Two indexes were applied for fluoroscopic detection of distal fibula malrotation, i.e. the contour profile change in lateral malleolar shape, and the intrinsic structure appearance of lateral malleolar fossa cortex. Postoperative talofibular joint congruency was measured on axial CT scan to confirm the reduction quality. RESULTS: Using the two radiographic parameters for intraoperative fluoroscopic evaluation, we finally achieved satisfying reduction and fixation of the lateral malleolus in all 56 cases. A more spoon-shaped fibula profile and disappearance of the lateral fossa cortex shadow indicates an internal rotation, while a more pointed blade-shaped fibula profile and disappearance of lateral fossa cortex shadow indicates an external rotation. Postoperative CT scanning identified distal fibular no rotation in 44 cases (78.6%), mild rotation less than 5° in 12 cases (21.4%), with 7 cases internal rotation (mean 3.1°) and 5 cases external rotation (mean 2.8°). CONCLUSION: Using conventional intraoperative fluoroscopy on mortise view, new radiographic parameters can provide reliable method to detect rotational malreduction of the lateral malleolus.

18.
Semin Diagn Pathol ; 36(6): 423-433, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31358425

RESUMO

Immunoglobuline G4-related disease (IgG4-RD) is a systemic disease that can involve virtually any organs including the biliary tract and liver. The biliary tract involvement of IgG4-RD is known as IgG4-sclerosing cholangitis (IgG4-SC) and may or may not present with an inflammatory pseudotumor. Large bile ducts such as extrahepatic, hilar, and perihilar ducts are typically affected and demonstrate marked bile duct wall thickening and develop strictures. Histologically, the involved ducts show transmural dense lymphoplasmacytic infiltrates with storiform fibrosis extending into peribiliary glands and periductal soft tissue. The luminal epithelium is usually preserved. Tissue eosinophilia and obliterative phlebitis are also frequently noted. Liver biopsy findings of IgG4-SC are heterogeneous and rather nonspecific, but two features specific to IgG4-SC have been described: >10 IgG4-positive plasma cell/HPF and small portal-based fibroinflammatory nodules. Secondary changes, due to downstream bile duct obstruction are often appreciated. When considering the differential diagnosis, primary sclerosing cholangitis and cholangiocarcinoma are great clinical and histologic mimics of IgG4-SC. Liver involvement in IgG4-RD has not been well characterized and includes IgG4-hepatopathy and IgG4-related autoimmune hepatitis (AIH). IgG4-hepatopathy is a generic term covering hepatic lesions related to IgG4-RD and /or IgG4-SC. It includes primary liver parenchymal changes inherent to IgG4-RD, liver parenchymal involvement of IgG4-SC, and secondary changes related to IgG4-SC. IgG4-related AIH is characterized by clinical and histologic features of classical AIH but with prominent (>10/HPF) IgG4-positive plasma cells. It is unclear whether this represents a hepatic manifestation of IgG4-RD or a subset of AIH with increased IgG4-positive plasma cells at the present time. Synchronous or metachronous involvement of other organs, offers a clue to make this distinction. IgG4 immunohistochemistry has an important role in diagnosing IgG4-RD. But the diagnosis cannot be made solely based on the number of IgG4-positive plasma cells, and results need to be interpreted with caution as increased IgG4-positive plasma cells can be seen in other inflammatory conditions or even in malignancy.

19.
Anal Chim Acta ; 1073: 45-53, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31146835

RESUMO

A novel and ultrasensitive electrochemiluminescent (ECL) bioassay has been developed for the detection of atrazine (ATZ), whereby bifunctional S, N-codoped carbon dots (S, N-CDs) and activated mesoporous bicarbons (BCs) have been innovatively integrated to synergistically amplify the ECL signal. When endogenous dissolved O2 is used as a coreactant, its sluggish reduction hinders the enhancement of ECL intensity of the luminophore, thus restricting its further application in bioanalysis. Here, bifunctional S, N-CDs severe as not only the ECL luminophore but the coreaction accelerator of dissolved O2 to generate more intermediates to boost the coreaction without using any other coreactant and coreaction accelerator. The as-formed nanoarchitectures of BCs possess enlarged surface area as the nanocarriers. They could provide adequate active sites for immobilization of tyrosinase (Tyr), which greatly prompts the ECL bioassay applications. Such a smart integration of bifunctional S, N-CDs, activated mesoporous BCs and the enzyme inhibition reaction achieves a unique and attractive high-performance signal-on ECL bioassay, realizing ultrasensitive detection of ATZ. Under the optimal condition, this bioassay exhibits two linear ranges, from 0.0001 to 0.01 µg L-1 and 0.01-20 µg L-1 with a detection limit of 0.08 ng L-1 at signal to noise ratio of 3. The as-fabricated assay is sensitive and economical, opening a new way for the enhancement of ECL signal output and a versatile strategy for ultrasensitive ECL bioanalysis.


Assuntos
Atrazina/análise , Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições Luminescentes , Monofenol Mono-Oxigenase/química , Nanopartículas/química , Atrazina/metabolismo , Carbono/química , Monofenol Mono-Oxigenase/metabolismo , Nanopartículas/metabolismo , Tamanho da Partícula , Porosidade , Pontos Quânticos/química , Propriedades de Superfície
20.
Environ Sci Technol ; 53(14): 8333-8341, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31241331

RESUMO

In this study, we report that liquid nitrogen treatment is a promising zero-valent iron activation method that does not remove the iron oxide shell; this can improve the apparent Cr(VI) removal rate constant of zero-valent iron by about 4-120 times, depending on the particle sizes and the suppliers of zero-valent iron. It was found that liquid nitrogen, with its low temperature of 77 K, could crack the iron oxide shell of zero-valent iron to produce abundant fractures because of the different thermal expansion coefficients of iron oxide and iron. These fractures provided suitable mass transfer channels for the inward transfer of water/oxygen molecules to the iron core and the subsequent in situ generation of Fe(II) for the reduction of Cr(VI) to Cr(III). More importantly, systematic characterizations confirmed the generation of an Fe(III)/Cr(III)/Cr(VI) composite on the surface of zero-valent iron during the removal, suggesting its environmental benignancy. This study provides a novel physical zero-valent iron activation method, sheds light on the importance of the iron oxide shell of zero-valent iron on Cr(VI) removal, and clarifies the intrinsic Cr(VI) removal mechanism of zero-valent iron.


Assuntos
Ferro , Poluentes Químicos da Água , Cromo , Compostos Férricos , Nitrogênio
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