Preparation and characterization of carboxymethyl cellulose capped zinc oxide nanoparticles: A proof-of-concept study.

Zinc oxide (ZnO) is one of the promising food additives, which adds nutrients and provides antimicrobial properties when incorporated into various food matrices. In this study, carboxymethyl cellulose capped ZnO (ZnO-CMC) were developed via a low-energy and cost-effective technique without calcination or grinding. The fabrication involved two steps: crosslinking Zn2+ ions with CMC through electrostatic interactions and generation of ZnO nanoparticles with CMC as capping agent. After mild heating, the crystalline structure of ZnO-CMC was confirmed by WAXS. Both FTIR and AFM studies illustrated that ZnO was physically trapped by CMC molecules, resulting in a physical barrier to prevent aggregation. SEM verified that the ZnO-CMC had a size of 50-80 nm with comparable morphology to commercial ZnO. Overall, CMC played a key role in controlling growth and inhibiting agglomeration of ZnO. Given the small and uniform particle size, the obtained ZnO-CMC is ready to be incorporated into different food matrices.

Self-assembled caseinate-laponite® nanocomposites for curcumin delivery.

In this study, novel self-assembled protein-clay nanocomposites were developed for curcumin delivery. Experimentally, curcumin was dissolved and deprotonated in sodium caseinate-laponite® (NaCas-LAP) dispersion at pH 12.0 for 30 min followed by neutralization to pH = 7. Due to the pH-mediated dissociation and re-association process, curcumin was successfully encapsulated into NaCas-LAP nanocomposites. The colloidal properties and encapsulation capabilities of NaCas-LAP nanocomposites were investigated, including particle size, zeta potential, encapsulation efficiency, release profile in simulated gastrointestinal tract, as well as nanoscale morphology. The results indicated that upon neutralization, NaCas-LAP nanocomposites were re-associated into smaller particles due to strong hydrophobic interactions among NaCas, LAP and curcumin. Specifically, 0.10% curcumin loaded nanocomposites prepared with 2% NaCas and 0.5% LAP showed improved encapsulation performance (73.4%) with smaller particle size (100 nm). The as-prepared protein-clay nanocomposites hold promising potential to deliver lipophilic bioactive compounds, such as curcumin.

A Non-Invasive Scoring System to Differential Diagnosis of Clear Cell Renal Cell Carcinoma (ccRCC) From Renal Angiomyolipoma Without Visible Fat (RAML-wvf) Based on CT Features.

BACKGROUND: Renal angiomyolipoma without visible fat (RAML-wvf) and clear cell renal cell carcinoma (ccRCC) have many overlapping features on imaging, which poses a challenge to radiologists. This study aimed to create a scoring system to distinguish ccRCC from RAML-wvf using computed tomography imaging. METHODS: A total of 202 patients from 2011 to 2019 that were confirmed by pathology with ccRCC (n=123) or RAML (n=79) were retrospectively analyzed by dividing them randomly into a training cohort (n=142) and a validation cohort (n=60). A model was established using logistic regression and weighted to be a scoring system. ROC, AUC, cut-off point, and calibration analyses were performed. The scoring system was divided into three ranges for convenience in clinical evaluations, and the diagnostic probability of ccRCC was calculated. RESULTS: Four independent risk factors are included in the system: 1) presence of a pseudocapsule, 2) a heterogeneous tumor parenchyma in pre-enhancement scanning, 3) a non-high CT attenuation in pre-enhancement scanning, and 4) a heterogeneous enhancement in CMP. The prediction accuracy had an ROC of 0.978 (95% CI, 0.956-0.999; P=0.011), similar to the primary model (ROC, 0.977; 95% CI, 0.954-1.000; P=0.012). A sensitivity of 91.4% and a specificity of 93.9% were achieved using 4.5 points as the cutoff value. Validation showed a good result (ROC, 0.922; 95% CI, 0.854-0.991, P=0.035). The number of patients with ccRCC in the three ranges (0 to <2 points; 2-4 points; >4 to ≤11 points) significantly increased with increasing scores. CONCLUSION: This scoring system is convenient for distinguishing between ccRCC and RAML-wvf using four computed tomography features.

Chitosan-based hydrogel beads: Preparations, modifications and applications in food and agriculture sectors - A review.

Chitosan is produced by deacetylation of chitin, the second-most abundant biopolymer on earth. With three types of reactive functional groups, one amino group and both primary and secondary hydroxyl groups, chitosan has been used as a popular biomaterial for synthesis of three-dimensional and flexible hydrogel beads that swell in water and biological fluids. Chitosan-based hydrogel beads have been found in a wide range of applications in food and agriculture sectors. This review first provides an overview of traditionally used and recently developed methods for preparation and modification of chitosan-based hydrogel beads, and then discusses the advances in the most recent five years in their applications for delivery of food bioactive compounds and treatment of agricultural recycled wastewater.

Aeroembolism in left atrium during catheter ablation of atrial fibrillation in a patient with dextrocardia: a case report and review of the literature.

BACKGROUND: Air embolus penetrating into heart chamber as a complication during percutaneous radiofrequency catheter ablation has been infrequently reported. CASE PRESENTATION: A 55-year-old man with dextrocardia who suffered from abdominal pain was suspected to have multiple arterial thromboembolisms, which might have originated from left atrium thrombosis since he had atrial fibrillation. He received oral anticoagulant therapy and catheter ablation of the arrhythmia. During the ablation procedure, an iatrogenic aeroembolism penetrated into the left atrium due to improper operation. Ultimately, the entire air embolus was extracted from the patient, who was free of any aeroembolism events thereafter. CONCLUSIONS: It is essential for an operator to pay full attention to all details of the procedure to avoid an aeroembolism during catheter ablation. In case of aeroembolism, removal by aspiration is an optimal and effective treatment.

Percutaneous closure of postinfarct muscular ventricular septal defects: a multicenter study in China.

BACKGROUND: Surgical repair is an effective method to treat ventricular septal defect (VSD) complicating acute myocardial infarction (AMI). However, the mortality rate remains high. This study was designed to assess the immediate and mid-term results of transcatheter closure of postinfarct muscular VSDs. METHODS: Data were retrospectively collected from 42 AMI patients who underwent attempted transcatheter VSD closure between 2008 and 2012 in seven heart centers of China. RESULTS: Nine patients underwent emergent VSD closure in the acute phase (within two weeks from VSD) while the others underwent elective closure. The time between VSD occurrence and closure in emergency group and elective group was 7.7 ± 2.3 days and 35 ± 14.5 days, respectively (p<0.01). The percentage of procedure success in the emergency group and elective group was 77.8% (7/9) and 97% (32/33), respectively (p=0.048). The hospital mortality was higher for emergent closure in comparison to elective closure (66.7% vs. 6.1%, p<0.01). During a median follow-up of 25 months (0-58 months), two patients died at 8 and 29 months, respectively, and no serious complications occurred in other patients. CONCLUSION: Interventional postinfarct VSD closure is a safe and effective approach that can be performed with a high procedural success rate, with favorable outcomes if it can be undertaken >14 days postinfarct.

[Preliminary clinical experience on radiofrequency catheter ablation of right-sided accessory pathway guided by Ensite-NavX navigation].

OBJECTIVE: To explore the feasibility and methodology of radiofrequency catheter ablation (RFCA) guided by 3D navigation system (Ensite-NavX) for right atrioventricular accessory pathway. METHOD: Thirty-three cases of right accessory pathway atrioventricular reentrant tachycardia including 16 cases in right free wall, 3 in right middle septum, 14 in right posterior septum; 23 cases of dominant accessory pathway and 10 cases of concealed were treated by RFCA guided by NavX navigation. NavX navigation modeling method or spatial localization method was exploited to locate target positioning. RESULT: All patients were successfully ablated without serious complications. Among them, 25 cases were operated without exposure to X-ray, 7 patients were exposed for several seconds to verify catheter position, 1 case in right free wall was ablated under X-ray combined with Swartz sheath ablation. CONCLUSION: Nonfluoroscopy or less fluoroscopy RFCA for right atrioventricular accessory pathway with Ensite-NavX is safe and feasible, modeling or spatial orientation method are helpful to locate the ablation target positioning.

[Comparison of cryoablation and radiofrequency ablation for treating atrioventricular nodal reentrant tachycardia].

OBJECTIVE: To compare the efficacy and safety between cryoablation (Cryo) and radiofrequency (RF) ablation for treating patients with atrioventricular nodal reentrant tachycardia (AVNRT). METHODS: Patients with AVNRT (n = 304) were divided into Cryo group (n = 67) and RF group (n = 237). The procedure success rate, complete slow pathway block rate, atrioventricular block rate and relapse rate were compared between two groups. RESULTS: There was no statistically difference between 2 groups in the success rate (Cryo group 98.5% vs RF group 97.0%, P = 0.820), complete slow pathway block rate (Cryo group 98.5% vs RF group 91.6%, P = 0.088), atrioventricular block rate (Cryo group 0 vs RF group 2.5%, P = 0.413), relapse rate (Cryo group 0 vs RF group 1.7%, P = 0.643). But Cryo group had more advantage than RF group. CONCLUSION: Efficacy and safety were comparable between cryoablation and radiofrequency ablation for treating patients with AVNRT.

A glass microfluidic chip for continuous blood cell sorting by a magnetic gradient without labeling.

This paper presents a microfluidic chip for highly efficient separation of red blood cells (RBCs) from whole blood on the basis of their native magnetic properties. The glass chip was fabricated by photolithography and thermal bonding. It consisted of one inlet and three outlets, and a nickel wire of 69-microm diameter was positioned in the center of a separation channel with 149-microm top width and 73-microm depth by two parallel ridges (about 10 microm high). The two ridges were formed simultaneously during the wet etching of the channels. The nickel wire for generating the magnetic gradient inside the separation channel was introduced from the side of the chip through a guide channel. The external magnetic field was applied by a permanent magnet of 0.3 T placed by the side of the chip and parallel to the main separation channel. The RBCs were separated continuously from the 1:40 (v/v) diluted blood sample at a flow rate in the range 0.12-0.92 microL/min (9-74 mm/min) with the chip, and up to 93.7% of the RBCs were collected in the middle outlet under a flow rate of 0.23 microL/min. The cell sedimentation was alleviated by adjusting the specific density of the supporting media with bovine serum albumin. Quantum dot labeling was introduced for visual fluorescence tracking of the separation process. The uneven distribution phenomenon of the blood cells around the nickel wire was reported and discussed.

A thermostat chip of indium tin oxide glass substrate for static polymerase chain reaction and in situ real time fluorescence monitoring.

A thermostat chip of indium-tin oxide glass substrate for static chip polymerase chain reaction (PCR) is, for the first time, introduced in this paper. The transparent conductive layer was used as an electro-heating element. Pulse width modulation and fuzzy proportional integration-differentiation algorithm were adopted in the temperature programming of the chip. The temperature distribution was investigated, and a dynamic control precision within +/-2 degrees C was achieved. The highest ramping rates were 37 degrees Cs(-1) for heating and 8 degrees Cs(-1) for cooling with an electric fan. The PCR reaction vials were constructed with polyethylene tubes or poly(dimethylsiloxane) directly on the thermostat chip; the chip had a typical size of 25 mm x 25 mm and a thickness of 1.1mm. Static chip PCR was successfully demonstrated either in a single vial or in an up to 8-parallel array vials. In situ real time fluorescence monitoring during PCR of a lambda DNA fragments (236bp) with SYBR Green I was demonstrated using a blue light emission diode as a light source and a photomultiplier as a detector. The method proposed here is characterized by open access, easy fabrication and low cost. This work could be the basis for developing a portable real time PCR system with disposable chips for point of care tests.

Optimization of direct whole blood PCR amplification with applications on a static thermostat chip.

In this paper, direct whole blood PCR amplifications on a static chip thermostat without sample purifications are demonstrated; in these amplifications, problems such as cross-interferences and contaminations could be avoided. The amplification conditions, such as the compositions of reagents and thermal programs, were investigated systematically by a GeneAmp PCR system with a native p53 gene segment (about 543 bp) of human genome and an exterior lambda DNA segment (about 500 bp) as targets. Direct amplifications of p53 and K-ras (about 157 bp) gene segments from 0.5 microL blood samples were successfully demonstrated by a static PCR chip with an indium tin oxide glass substrate. The chip thermostat has a typical size of 25 mm x 25 mm, and a polyethylene tube was used as the PCR vial on the glass surface of the chip. Fuzzy proportional integration-differentiation algorithms were adopted in temperature controls of the chip with an aid of a micro-Pt100 sensor. In the direct PCR with the thermostat chip, the whole process only involves automatic thermal programs. This work demonstrated that a chip PCR for field test without desktop facilities is possible either for a point of care test or for forensic analysis.

DNA purification on a lab-on-valve system incorporating a renewable microcolumn with in situ monitoring by laser-induced fluorescence.

Bead injection in a lab-on-valve (LOV) system was adopted for DNA purification via micro solid-phase extraction (SPE) with a renewable silica microcolumn packed in a channel of the LOV unit. The complex matrix components in human whole blood, including proteins, were well eliminated by choosing properly the sample loading and elution media. The DNA purification process was monitored on-line by using laser-induced fluorescence in a demountable side part of the LOV unit incorporating optical fibers. The practical applicability of the entire system was demonstrated by separation/purification of lambda-DNA in a simulated matrix and human blood genetic DNA by performing SPE, in situ monitoring of the purified products, and postcolumn PCR amplification. When DNAs in a simulated matrix (10.0 ng microl-1 lambda-DNA, 50 ng microl-1 bovine serum albumin, 1.0% Triton X-100) were processed in the present system and laser-induced fluorescence was monitored at 610 nm, an overall extraction/collection efficiency of 70% was achieved by employing identical sample loading and an elution flow rate of 0.5 microl s-1, along with a precision of 3.8% relative standard deviation. DNA separation and purification from human whole-blood samples were performed under similar conditions.