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The mechanochemical encapsulation of enzymes during the synthesis of metal–organic frameworks (MOF) have been thought to be a natural, economical, new, and environmentally friendly step in synthesizing supported enzymatic catalysts. In this study, for the first time, a mechanochemical technique was employed to immobilize Candida rugosa lipase (CRL), and two zinc-based MOF types (Zn-MOF-74 and ZIF-8) were preferred. The enzyme kinetics and immobilization parameters (pH, temperature, thermal stability and reusability) of the prepared encapsulated enzymes (Zn-MOF-74@CRL and ZIF-8@CRL) were investigated. The prepared encapsulated enzymes were characterized by FTIR, SEM and XRD. It was observed that the catalytic activity of Zn-MOF-74 @CRL was six times higher than that of ZIF-8@CRL. After five reuses, the activities of Zn-MOF-74@CRL and ZIF-8@CRL were found to be 81% and 73% retained, respectively. After being subjected to 60 °C for 120 min, ZIF-8@CRL and Zn-MOF-74@CRL maintained their activities at 65% and 73%, respectively. The enantioselective hydrolysis reaction of racemic naproxen methyl ester was chosen as the model reaction. The results showed Zn-MOF-74@CRL possessed better enantioselectivity (E = 245) than ZIF-8@CRL (E = 136). This study demonstrated that it is possible to create biocatalysts with excellent catalytic properties for the pharmaceutical industry using MOFs produced by the mechanochemical method. [Display omitted] • Two zinc based-two metal organic frameworks (ZIF-8 and Zn-MOF-74) were prepared. • Zn-MOF-74 and ZIF-8 were used as support materials to immobilize CRL. • Zn-MOF-74@CRL showed lipase activity 6 times higher than ZIF-8@CRL. • After recycling 5 times, Zn-MOF-74@CRL retained 81% of its initial activity. [ABSTRACT FROM AUTHOR]

On solid surfaces immersed in a liquid medium, a biofilm layer which is called biofouling formed over time by organic molecules and microorganisms. It is important to produce new eco-friendly ideas can prevent this undesired phenome. In this study, we focused on the antifouling performance of polyaniline (PANI), whose anticorrosive properties have been already known. The main purpose of this study was to immobilize hydrolytic enzymes that could break down biomolecules and microorganisms and how this would contribute to the antifouling performance of the PANI coating. When α-amylase, DNAse, glucose oxidase, α-chymotrypsin, lipase and pectinase enzymes immobilized into PANI that was synthesized in ammonium oxalate (PANI AO) and sodium salicylate (PANI SS) electrolytes, α-amylase containing film (PANI SS -A) showed the highest performance (76.5% antifouling activity). The surface properties after keeping in the Mediterranean Sea for 12 days were compared by digital photography, Scanning Electron microscope (SEM) and fluorescence microscope images, also with Energy Dispersive X-Ray (EDX) analysis and crystal violet staining. Carbohydrate and protein amounts and CFU (Colony Forming Units) values of biofilms formed on the surface for bare, PANI SS and PANI SS -A coupons after keeping 12 days in the Mediterranean Sea were determined. Vibrio species (V.harveyi , V.alginolyticus , V.parahaemolyticus) were detected in the biofilms by Matrix- Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) analysis. [Display omitted] • Polyaniline film has an antifouling effect in the marine environment. • The type of electrolyte used in the synthesis of polyaniline affects the antifouling performance. • The presence of enzymes on the surface significantly reduced biofilm formation. [ABSTRACT FROM AUTHOR]

Protein energy wasting (PEW) is the most important risk factor for morbidity and mortality in hemodialysis patients. Inadequate dietary protein intake is a frequent cause of PEW. Recent studies have identified fibroblast growth factor 21 (FGF21) as an endocrine protein sensor. This study aims to investigate the potential of FGF21 as a biomarker for protein intake and PEW and to investigate intradialytic FGF21 changes. Plasma FGF21 was measured using an enzyme-linked immunoassay. Complete intradialytic dialysate and interdialytic urinary collections were used to calculate 24-h urea excretion and protein intake. Muscle mass was assessed using the creatinine excretion rate and fatigue was assessed using the Short Form 36 and the Checklist Individual Strength. Out of 59 hemodialysis patients (65 ± 15 years, 63% male), 39 patients had a low protein intake, defined as a protein intake less than 0.9 g/kg/24-h. Patients with a low protein intake had nearly twofold higher plasma FGF21 compared to those with an adequate protein intake (FGF21 1370 [795–4034] pg/mL versus 709 [405–1077] pg/mL;P < 0.001). Higher plasma FGF21 was associated with higher odds of low protein intake (Odds Ratio: 3.18 [1.62–7.95] per doubling of FGF21; P = 0.004), independent of potential confounders. Higher plasma FGF21 was also associated with lower muscle mass (std β: −0.34 [-0.59;-0.09];P = 0.009), lower vitality (std β: −0.30 [-0.55;-0.05];P = 0.02), and more fatigue (std β: 0.32 [0.07;0.57];P = 0.01). During hemodialysis plasma FGF21 increased by 354 [71–570] pg/mL, corresponding to a 29% increase. Higher plasma FGF21 is associated with higher odds of low protein intake in hemodialysis patients. Secondarily, plasma FGF21 is also associated with lower muscle mass, less vitality, and more fatigue. Lastly, there is an intradialytic increase in plasma FGF21. FGF21 could be a valuable marker allowing for objective assessment of PEW. [ABSTRACT FROM AUTHOR]

Metal organic frameworks (MOFs) are hybrid organic inorganic materials with unique properties such as well-defined pore structure, extremely high surface area, excellent chemical-thermal stability. MOFs-based constructs have been extensively engineered and used for applications, such as enzyme immobilization for bio-catalysis. To obtained a zeolitic imidazole framework-8 (ZIF-8) for enzyme immobilization, Candida rugosa lipase (CRL) was pretreated with calix [4]arene tetracarboxylic acid (Calix) and reacted with Zn and imidazole by co-precipitation method. The prepared biocomposite was characterized by SEM, EDX, FT-IR, and XRD. The prepared CRL@Calix-ZIF-8 with high encapsulation efficiency showed improved resistance to alkali and thermal conditions. The CRL@Calix-ZIF-8 with the biocatalytic activity was 2-folds higher than that of the CRL@ZIF-8 (without Calix). The free lipase lost its catalytic activity completely at 60 °C after 100 min, while the CRL@Calix-ZIF-8 and CRL@ZIF-8 retained about 84% and 73%. It was found that CRL@Calix-ZIF-8 and CRL@ZIF-8 still retained ~83 and 67% of catalytic activity after its 6th use, respectively. The kinetic resolution of the immobilized lipases was examined for enantioselective hydrolysis of racemic naproxen methyl ester. CRL@Calix-ZIF-8 showed enantioselectivity against the racemic naproxen methyl ester, with E = 183 and 131 compared to the CRL@ZIF-8. [Display omitted] • CRL@Calix-ZIF-8 exhibited 2-fold improved catalytic activity compared to CRL@ZIF-8. • CRL@Calix-ZIF-8 retained 83% of catalytic activity after its 6th use. • CRL@Calix-ZIF-8 showed hydrolysis of racemic naproxen methyl ester. [ABSTRACT FROM AUTHOR]

Junctional ectopic tachycardia(JET) is a rare childhood arrhythmia originating from the area adjacent to the atrioventricular(AV) node. It often occurs after surgical procedures like repair of Tetralogy of Fallot, atrioventricular septal defect and ventricular septal defect, which are all performed in that area. While AV block (AVB) can occur after JET, it is very rare for late JET occurring after early postoperative AVB to be followed by normal sinus rhythm (NSR). There is no information in the literature related to the pathophysiology of this phenomenon. In this text, we present 4 patients who developed complete AV block(CAVB) in the early postoperative period (within the first 24h) after JET in late period (>72h) and returned to NSR with first-degree AV block and then NSR during follow-up. Based on these cases, we hypothesize that there is a link between late JET after early postoperative CAVB and return to NSR. [ABSTRACT FROM AUTHOR]

In this study, iron magnetic nanoparticles capped with fluorescent calixarene derivatives (Fe 3 O 4 @Calix-2 and Fe 3 O 4 @Calix-3) were prepared in one-step using coprecipitation of Fe(II) and Fe(III) in basic solution. Different techniques were used to characterize the synthesized magnetic nanoparticles, such as Fourier Transform Infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and confocal microscopy. Candida rugosa was encapsulated on synthesized nanoparticles following sol–gel method. It has been observed that under the optimum conditions, the activity of encapsulated lipase (Fe 3 O 4 @Calix-2E) was 119 U/g of support which is 4.1 times more that of the encapsulated lipase without calix[4]arene derivative (Fe 3 O 4 @E). Comparative study show that the encapsulated lipase on nanoparticles has higher thermal and operational stability than encapsulated lipase without calix[4]arene derivative. Among these encapsulated lipase nanoparticles, Fe 3 O 4 @Calix-2 was capable of effectively catalyze hydrolysis of racemic Flurbiprofen methyl ester with high conversion of 49% and substrate enantiomeric excess (ees) of 85% at optimum pH and temperature. The efficiency of these nanoparticles was assessed by their reusability, for that after five consecutive operational uses these encapsulated lipase nanoparticles retained their conversion ratios up to 38% and 30% respectively, in the hydrolysis of (R,S)-Flurbiprofen methyl ester. The results showed that encapsulated lipases nanoparticle with calixarene moieties lead to increased activity, stability, reusability and enhanced stereoselectivity in kinetic resolution. [ABSTRACT FROM AUTHOR]

• Co-immobilized amylase, pectinase and cellulase can be used for juice clarification. • The enzymes covalently attached to the silica gel showed the highest efficiency. • Turbidity change with temperature had inverse trend depending on the enzyme amount. In this study, the use of co-immobilized amylase, pectinase and cellulase enzymes for clarification of apple, grape and pear juices were investigated. Four different co-immobilization method was applied and the highest activity was observed for co-immobilized enzymes onto silica gel. The effect of the enzyme units used in the co-immobilization, reaction temperature and time on turbidity and reducing sugar concentration were optimized by Response Surface Methodology (RSM) via Design Expert Software 8.0.7.1. applying 3-factor Box-Behnken design. Co-immobilized samples were reacted with the substrate solution in batch type and feedback packed bed column reactors and according to turbidity and reducing sugar concentration values, batch reactor efficiency was found to be higher. Finally, freshly squeezed apple, pear and grape juices were interacted with co-immobilized enzymes in the batch reactor system, and turbidity and reducing sugar concentrations were monitored over time. Changes were also observed in antioxidant activities depending on the enzyme treatment. [ABSTRACT FROM AUTHOR]

Abstract: Candida rugosa lipase (CRL) and porcine pancreatic lipase (PPL) were immobilised by entrapping and also by covalent binding for use in synthesis of isoamyl acetate (IAAc), which has a typical banana flavour. Lipase entrapment was carried out by dripping sodium alginate (Na-Alg)-chitosan (Chi)-lipase mixture into CaCl2-glutaraldehyde (GAL) solution to obtain Ca-Alg/ChiCRL/PPL. Immobilisation conditions were optimised as 1.5% Na-Alg, 1.5% chitosan and 0.15% GAL. Ca-Alg/ChiCRL/PPL samples showed the highest activity when they were dried upon reaching 27% of their initial weights. Covalent binding was achived with Chi modified with spacerarm via glutaraldehyde to get ChiCRL/PPL. The highest IAAc production was observed when 1,3-diaminopropane was used as a spacer arm. The best ester yield was achieved in heptane, at 40 and 45°C reaction temperatures, 50mM IAA and 50 or 75mM AA concentrations. The amount of IAAc was nearly 10 times higher for the batch type than for the continuous packed bed column reactor. [Copyright &y& Elsevier]

Abstract: Purpose: The aim of this study was to investigate modifiable risk factors and predictors for treatment failure (TF) in patients with ventilator-associated pneumonia (VAP) receiving appropriate antibiotic therapy. Materials and Methods: An observational cohort study performed in an intensive care unit (ICU) of a University hospital. Eighty-nine patients with VAP were enrolled in the study consecutively. Treatment failure was defined as lack of clinical and microbiological response to therapy within 2 weeks. Potential risk factors for TF, related with patients, microorganisms, and ICU therapies, were evaluated. Results: Mean age was 72 ± 13 years. Fifty-three of the patients had TF. Patients with TF were older, had more comorbidities, higher admission and Acute Physiology and Chronic Health Evaluation Score (APACHE II)-VAP scores, lower daily carbohydrate intake, and lymphocyte number below 1000/mm3 than the treatment success group. Transfusions, bacteremia, infection with multidrug-resistant microorganisms, initial bacterial load (CFU/mL), and steroid therapy were similar across the groups. Comorbidity (odds ratio [OR], 4.4; 95% CI, 1.2-16.8; P = .030), VAP-APACHE II scores above 16 (OR, 6.4; 95% CI, 2.1-18.6; P = .001), daily carbohydrate intake below 190 g/d (OR, 3; 95% CI,1.1-8.6; P = .038), lymphocyte number below 1000/mm3 (OR, 4.1; 95% CI, 1.3-12.9; P = .014) were independent predictors for TF. Conclusions: Patients with comorbidities, who are severely ill and lymphocytopenic at the time of VAP diagnosis, are at high risk for TF. [Copyright &y& Elsevier]

Background:Nasotracheal intubation is often necessary in patients undergoingelective or emergency maxillofacial surgery. Previous studies have suggested that the increase in blood pressure after nasotracheal intubation is significantly greater than the increase after orotracheal intubation. Many drugs, including narcotic analgesics, are effective in modifying cardiovascular responses to orotracheal intubation.Objective:The effects of remifentanil and alfentanil on the cardiovascularresponses to nasotracheal intubation were compared in healthy patients scheduled to undergo surgery.Methods:This prospective, randomized, double-blind study was conductedat the Department of Anesthesiology and Reanimation, Faculty of Medicine, Dicle University, Diyarbakir, Turkey. Patients aged 16 to 65 years scheduled to undergo elective maxillofacial surgery and who were American Society of Anesthesiologists status I or II were randomly assigned to receive remifentanil 1 microg/kg in 10 mL saline over 30 seconds followed by an infusion of 0.5 microg/kg x min, or alfentanil 10 microg/kg in 10 mL saline over 30 seconds followed by an infusion of saline. Anesthesia was then induced with propofol, cisatracurium, and 1% isoflurane with 66% nitrous oxide in oxygen. Heart rate (HR) and systolic and diastolic arterial pressures (SAP and DAP, respectively) were measured noninvasively at 2 minutes before general anesthesia induction (baseline); 2 minutes after induction; and 1, 3, and 5 minutes after nasotracheal intubation. Patients were monitored for cardiac changes using electrocardiography.Results:Forty consecutive patients were enrolled in the study. Twenty patients (11 males, 9 females; mean [SD] age, 27.7 [12.6] years) received remifentanil, and 20 patients (12 males, 8 females; mean [SD] age, 31.5 [17.2] years) received alfentanil. Two minutes after anesthesia induction, mean (SD) arterial pressures decreased significantly from baseline in the remifentanil group (changes, 22 [8]/11 [6] mm Hg) and the alfentanil group (changes, 10 [9]/12 [8] mm Hg) (both, P < 0.05). Changes in SAP and DAP followed a similar pattern in both groups, but SAP was significantly lower in the remifentanil group compared with that in the alfentanil group throughout the study period (all, P < 0.05). After 1 minute of intubation, DAP was significantly lower in the remifentanil group compared with that in the alfentanil group (66 [9] mm Hg vs. 73 [20] mm Hg; P < 0.05). Compared with baseline, HR was decreased significantly in both groups throughout the study (all, P < 0.05). Except SAP in the alfentanil group, SAP, DAP, and HR were increased 1 minute after intubation compared with preintubation values. However, SAP, DAP, and HR remained significantly lower compared with baseline values throughout the study period in both groups (all, P < 0.05) except DAP at 1 minute after incubation in the alfentanil group. Five patients in the remifentanil group and 2 patients in the alfentanil group required treatment of hypotension. None of the patients in either group required treatment of bradycardia.Conclusions:In this study in healthy surgical patients aged 16 to 65 years, remifentanil 1 microg/kg given over 30 seconds, followed by a remifentanil infusion of 0.5 microg/kg x min, was similarly effective compared with alfentanil 10 microg/kg in attenuating the pressor response to nasotracheal intubation, but the incidence of hypotension in patients administered remifentanil was high. [ABSTRACT FROM AUTHOR]

Abstract: Patients who have pulmonary atresia with intact ventricular septum have been shown to have a number of various myocardium anomalies like ischemia, fibrosis, infarction, rupture, disarray, spongious myocardium and ventricular endocardial fibroelastosis. Multiple connections have been found between right ventricular myocardial sinusoids and small branches of intramural coronary arteries. Noncompation of ventricular myocardium has been shown to be the result of myocardial ischemia or excessive pressure preventing the reduction of embryonic sinusoids. The persistence of intertrabecular recesses that are connected to both the ventricular cavity and coronary circulation is the result of this process. In this text, we describe a PA-IVS patient who underwent patent ductus arteriosus stenting and pulmonary valve perforation to create antegrade flow and later developed left ventricular noncompaction. We posit that there is a connection between right ventricular coronary sinusoids and noncompaction sinusoids. As our patient’s RV outflow tract stenosis and RV pressure increased, the coronary circulation connected to coronary sinuses became sufficient and LV function improved, which further supports our hypothesis. [Copyright &y& Elsevier]

Although testicular germ cell tumors have become curable neoplasms, a better understanding of the clinicopathologic features is needed for the rare manifestations associated with treatment failure. We report a rare case of metastatic pure choriocarcinoma involving the small intestine arising from a testicular mixed germ cell tumor. In a patient who developed massive upper gastrointestinal hemorrhage during treatment, the intestinal metastases and focus of bleeding could only be determined by laparotomy. We propose an approach for the determination of subclinical intestinal metastases of testicular germ cell tumor; the case is discussed in light of similar reports in literature. [Copyright &y& Elsevier]