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A novel potentiometric sensor, based on carbon paste electrode (CPE), modified with ion-imprinted polymer (IIP) and multi-walled carbon nanotubes (MWCNTs), is introduced for detection of chromium (III). The IIP nanomaterial was synthesised and characterised by using scanning electron microscopy and Fourier Transform Infrared. The modification of the CPE with the IIP (as a ionophore) resulted in an all-solid-state Cr(III)-selective sensor. However, the presence of appropriate amount of MWCNTs in the electrode composition was found to be necessary to observe Nernstian response. The optimised electrode composition was 76.7% graphite, 14.3% binder, 5% IIP, and 4% CNT. The proposed sensor exhibited Nernstian slope of 20.2 ± 0.2 mV decade−1in the working concentration range of 1.0 × 10−6−1.0 × 10−1 mol L−1(52 µg L−1–5.2 g L−1), with a detection limit of 5.9 × 10−7 mol L−1(30.68 µg L−1) and a fast response time of less than 40 s. It displayed a stable potential response in the pH range of 2–5. It exhibited also high selectivity over some interfering ions. The proposed sensor was successfully applied for the determination of Cr(III) in real samples (sea, river water and soil). [ABSTRACT FROM PUBLISHER]

Background: Hepatitis B virus (HBV) can cause cirrhosis of the liver and hepatocellular carcinoma. Due to the lack of sufficient immune response in whole population, several studies have been conducted to improve the efficacy of alum- based HBV vaccine. Here, naloxone/alum mixture as adjuvant was used for the hepatitis B surface antigen HBsAg vaccine and immune parameters evaluated in immunized mice. Objectives: The present study aimed at investigating the effect of naloxone/alum mixture for the HBsAg vaccine and comparing to Fendrix vaccine. Methods: Female Balb/c mice were vaccinated at day 0, 14, and 28 with alum-based vaccine or naloxone/alum mixture vaccine in different doses. Naloxone/alum vaccine groups received a dose of 3, 6, or 10 mg/kg of naloxone (NLX) in the vaccine formulation. One group received routine HBsAg alum vaccine and another group received Fendrix vaccine. Some groups received naloxone plus HBsAg without alum and a group received HBsAg without adjuvant. Phosphate buffered saline (PBS), naloxone, and alum were also injected into the control groups separately. Finally, the naloxone/alum formulated vaccine was compared with the Fendrix and routine alum- based vaccine with respect to the levels of total anti-HBS antibody, IFN-, IL-4, IgG1, IgG2a, and the level of lymphocyte proliferation. Results: The level of total anti-HBS antibody in naloxone formulated vaccine was comparable with Fendrix. Meanwhile, IFN- /IL-4 ratio level was significantly higher in naloxone formulated vaccine groups versus mere vaccine group. IgG2a was also higher in the naloxone formulated vaccine groups. Conclusions: Based on the data presented in the present study, it was found that naloxone/alum mixture has the ability to shift the immune response towards Th1 pattern and potentially increase immunity against infections. [ABSTRACT FROM AUTHOR]

Abstract A novel nano-sized imprinted polymer/multi-walled carbon nanotube (MWCNTs)-based potentiometric sensor is introduced for lactic acid (LA) sensing in dairy products. The imprinted polymer was synthesized using allyl amine (AA) and ethylene glycol dimethacrylate as functional monomer and cross-linker, respectively. It was demonstrated that the amide linkage was created between LA and AA during copolymerization reaction which was finally hydrolyzed when removing template from the synthesized MIP. It was also shown that the MIP cavities, compatible with LA anion, were created during polymerization reaction which influenced the potentiometric response behavior of the MIP-based electrode. This novel potentiometric sensor is a carbon rod electrode, coated with a membrane consisting of the MIP nanoparticles (2.5%), MWCNTs (2%), dibutylphthalate (DBP) (65%), poly-vinyl chloride (PVC) (28.5%) and tetra phenyl phosphonium bromide (TPPB) (2%). The active ion sensed by the electrode is the LA anion formed at elevated pH condition. The sensor exhibited Nernstian slope of 30.3 ± 0.4 mVdecade−1 in the working concentration range of 1.0 × 10−1to 1.0 × 10−6 mol L−1 with detection limit of 7.3 × 10−7 mol L−1. The sensor displayed a stable potential response in the pH range of 5–8 and fast response time of less than 60 s. It exhibited also high selectivity over the interfering species. The proposed sensor was successfully applied for the determination of LA in real samples (milk and yoghurt). Graphical abstract fx1 Highlights • A new nano-sized imprinted polymer was synthesized for lactic acid recognition. • Ally amine was used as the functional monomer for LA imprinting. • LA-MIP was used as ionophore of the membrane coated graphite rod electrode. • Including of MWCNTs in the membrane improved the electrode performance. • The electrode exhibited response time of 60 s and DL of detection limit of 0.73 µM. [ABSTRACT FROM AUTHOR]

Background: Measurement of small bowel length is an essential step in performing bariatric surgery. Surgeons need to measure bowel length in order to create alimentary and biliopancreatic limbs. Inaccurate bowel measurement may affect the outcome of surgery. However, it is not clear how accurate the measurement of bowel length is by surgeons., Methods: Two image quizzes marking certain lengths of jejunum were sent to participants. They were asked to estimate the length of marked bowels in maze quizzes. The Error of estimation, prevalence of significant error (error greater than 30 percent of actual length), and the relationship between different participant characteristics was investigated., Results: A total of 86 participants answered the questionnaire. The mean error of estimation was 4.62 cm (27%). Twenty-eight participants (33%) had significant errors in estimation of bowel length., Conclusion: While there are surgeons that can estimate bowel length with decent accuracy, significant errors in estimation of bowel length are not uncommon among surgeons. Surgeons should consider adopting techniques for accurate measurement of the small intestine., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2022 MIrzaee, Golzarand, Parsaei, Toolabi and Amirbeigi.)