Controlled Functionalization of Multiwalled Carbon Nanotubes by in Situ Atom Transfer Radical Polymerization

The in situ ATRP (atom transfer radical polymerization) “grafting from” approach was successfully applied to graft poly(methyl methacrylate) (PMMA) onto the convex surfaces of multiwalled carbon nanotubes (MWNT). The thickness of the coated polymer layers can be conveniently controlled by the feed ratio of MMA to preliminarily functionalized MWNT (MWNT-Br). The resulting MWNT-based polymer brushes were characterized and confirmed with FTIR, 1H NMR, SEM, TEM, and TGA. Moreover, the approach has been extended to the copolymerization system, affording novel hybrid core−shell nanoobjects with MWNT as the core and amphiphilic poly(methyl methacrylate)-block-poly(hydroxyethyl methacrylate) (PMMA-b-PHEMA) as the shell. The approach presented here may open an avenue for exploring and preparing novel carbon nanotubes-based nanomaterials and molecular devices with tailor-made structure, architecture, and properties

Protein Sensing and Cell Discrimination Using a Sensor Array Based on Nanomaterial-Assisted Chemiluminescence

Cross-reactive sensor arrays, known as “chemical noses”, offer an alternative to time-consuming analytical methods. Here, we report a sensor array based on nanomaterial-assisted chemiluminescence (CL) for protein sensing and cell discrimination. We have found that the CL efficiencies are improved to varied degrees for a given protein or cell line on catalytic nanomaterials. Distinct CL response patterns as “fingerprints” can be obtained on the array and then identified through linear discriminant analysis (LDA). The sensing of 12 kinds of proteins at three concentrations, as well as 12 types of human cell lines among normal, cancerous, and metastatic, has been performed. Compared with most fluorescent or colorimetric approaches which rely on the strong interaction between analytes and sensing elements, our array offers the advantage of both sensitivity and reversibility

Multicolor Imaging of Cancer Cells with Fluorophore-Tagged Aptamers for Single Cell Typing

The discrimination of the type of cancer cells remains challenging due to the subtle differences in their expression of membrane receptors. In this work, we developed a multicolor cell imaging method for distinguishing the type of cancer cells with fluorophore-tagged aptamers. We found that the interaction between aptamers and cancer cells was affected by both of the sequence of aptamers and the labeled dyes. As the co-ownership of biomarkers for different cancer cell lines, the fluorophore-tagged aptamers interacted with different cancer cell lines in different degree, resulting in a distinct color to discriminate the type of cancer cells at single cell level. Taking advantage of the cross-reactive ability of the fluorophore-tagged aptamers, we could not only distinguish the cancerous cells quickly from large quantities of noncancerous cells, but also identify the type of the cancerous cells. This work has potential application for cancer diagnostic and therapy in the future

Synergistic Effects of Initial Moisture Content and Particle Size on Drying Rate and Heat Production during Bio-Drying of Sludge after Electro-Dewatering

Electro-dewatered sludge (EDS) can be bio-dried alone, instead of adding bulking agents. The initial moisture content (IMC) and particle size of the electro-dewatered sludge affect the efficiency and energy consumption during the bio-drying process. This study aimed to investigate the synergistic effects of sludge IMC and particle size on the drying rate and heat production of bio-drying with EDS. Experiments were conducted with two different IMC sludge and two different sludge particle sizes. Results showed that the highest moisture removal rate was 43.18% in treatment T4, which had materials with a smaller particle size (<3 mm) and lower IMC (38.69%). And bio-drying of T4 had the highest biological heat production (7413.14 kJ, i.e., 741.31 kJ/kg sludge), and the lowest bio-drying index (the ratio of water loss to volatile solid loss) was 7.10 among the four treatments. Five thin-layer drying kinetic models and a nonlinear regression method were analyzed to estimate the bio-drying kinetic parameters. The Midilli et al. model had a better fitting result, and the highest R2 value was 0.9929 during bio-drying of EDS. The new coefficients k (0.1465) and n (1.0898) were obtained. Through the heat balance, the heat used for evaporation was 40–57% of the total energy consumption (5873–9140 kJ). According to the PCA, the particle size had a great influence on the bio-drying process. Also, the particle size positively correlated with temperature, moisture ratio, and drying rate

Combined epidural-general anesthesia was associated with lower risk of postoperative complications in patients undergoing open abdominal surgery for pheochromocytoma: A retrospective cohort study

<div><p>Background</p><p>Current evidences show that regional anesthesia is associated with decreased risk of complications after major surgery. However, the effects of combined regional-general anesthesia remain controversial. The purpose of our study was to analyze the impact of anesthesia (combined epidural-general anesthesia vs. general anesthesia) on the risk of postoperative complications in patients undergoing open surgery for pheochromocytoma.</p><p>Methods</p><p>This was a retrospective cohort study. 146 patients who underwent open surgery for pheochromocytoma (100 received combined epidural-general anesthesia and 46 received general anesthesia) in Peking University First Hospital from January 1, 2002 to December 31, 2015 were enrolled. The primary outcome was the occurrence of postoperative complications during hospital stay after surgery. Multivariate Logistic regression models were used to analyze the association between the choice of anesthetic method and the risk of postoperative complications.</p><p>Results</p><p>17 (11.6%) patients developed complications during postoperative hospital stay. The incidence of postoperative complications was lower in patients with combined epidural-general anesthesia than in those with general anesthesia (6% [6/100] vs. 23.9% [11/46], P = 0.006). Multivariate Logistic regression analysis showed that use of combined epidural-general anesthesia (OR 0.219, 95% CI 0.065–0.741; P = 0.015) was associated with lower risk, whereas male gender (OR 5.213, 95% CI 1.283–21.177; P = 0.021) and perioperative blood transfusion (OR 25.879; 95% CI 3.130–213.961; P = 0.003) were associated with higher risk of postoperative complications.</p><p>Conclusions</p><p>For patients undergoing open surgery for pheochromocytoma, use of combined epidural-general anesthesia may decrease the occurrence of postoperative complications.</p></div

Postoperative outcomes.

Postoperative outcomes.</p

Ratio of patients free of postoperative complications.

<p>Postoperative complications were defined as grade II or higher on the Clavien-Dindo classification. PC = postoperative complications.</p

Intra- and postoperative variables.

<p>Intra- and postoperative variables.</p

Flow diagram of the study.

<p>Flow diagram of the study.</p

Data_Sheet_1_Comparison of two frailty indices in predicting life-threatening morbidity and mortality among older patients undergoing elective high-risk abdominal surgery.docx

BackgroundFrailty predicts an increased risk of postoperative morbidity and mortality. Comparison of the predictive performance between two deficit accumulation models of frailty, the modified frailty index (mFI) and the revised-Risk Analysis Index (RAI-rev), is poorly understood. This study compared the predictive abilities of the above two frailty indices in predicting life-threatening morbidity and mortality among older patients following elective high-risk abdominal surgery.MethodsThis retrospective cohort study extracted perioperative data of older patients (age ≥65 years) undergoing elective high-risk abdominal surgery at a single institution between January 2018 and December 2020. Preoperative frailty was screened by mFI and RAI-rev scoring systems. The primary outcome was the composite of postoperative life-threatening morbidity and mortality during hospitalization. Multivariable logistic regression analyses were performed to investigate the association of the two frailty indices with the primary outcome. Receiver-operating characteristic (ROC) curve was employed to test the predictive performances of the two frailty instruments in predicting the composite primary outcome. The difference between the area under the curves (AUCs) was assessed by DeLong’s test.Results1,132 older patients (mean age, 73.4 ± 6.2 years; 63.9% male) were included. Of these, 107 (9.5%) developed postoperative life-threatening morbidity and mortality. In multivariable logistic regression analyses, rising continuous frailty scores (mFI: adjusted OR 1.319 per 0.09-point increase in score, 95% CI 1.151–1.511, p ConclusionHigh mFI and RAI-rev scores were associated with an increased risk of life-threatening morbidity and mortality in older patients undergoing elective high-risk abdominal surgery. However, both frailty indices displayed poor discrimination for postoperative life-threatening morbidity and mortality.</p