Using 3D printed magnetic platform as support for screen printed electrode applied for p-toluenediamine detection in biological fluid and water samples.

The present work reports the development and application of a new electrochemical sensor for the determination of low concentration levels of p-toluenediamine (PTD) in biological fluids and surface water samples. The proposed sensor was developed using a 3D-printed magnetic device as platform for carbon screen printed electrode (CSPE) modified by magnetic nanoparticles functionalized with carboxylic groups and l-cysteine (MNP-CA-CYS). The results obtained from the morphological and electrochemical characterizations of the sensing platform enabled us to confirm the success of the sensor functionalization with l-cysteine and to have a better understanding of the electrochemical behavior and preconcentration of PTD on the electrode surface. PTD oxidation occurred at 0.24V on MNP-CA-CYS and the mechanism recorded an increase of 51.0% in anodic peak current. Under optimized conditions, the square wave voltammograms obtained for the electrode modified by 40.0 µL MNP-CA-CYS suspension at 1.0 mg mL-1, with accumulation time of 3 min, presented an analytical curve with linear range of 8.00 × 10-7 to 8.00 × 10-5 mol L-1, represented by the equation Iap = (0.383 ± 0.011)[PTD] - (8.112 ± 0.07) × 10-8 (R2 = 0.9994), and detection and quantification limits of 8.53 × 10-8 and 2.56 × 10-7 mol L-1, respectively. Finally, the proposed method was validated through comparison with high performance liquid chromatography coupled to diode array detector (HPLC-DAD) technique and was successfully applied for PTD determination in samples of surface water, tap water, fetal bovine serum and artificial urine.

Influence of vinification process over the composition of volatile compounds and sensorial characteristics of greek wines.

Wine is one of the most traditional consumed alcoholic beverages in the world. Millions of wine enthusiasts worldwide duly appreciate a wine of excellent quality in terms of physicochemical and sensorial properties. Different classes of wines have different volatile compositions and sensorial properties, which can be altered, depending on the vinification process and use of additives. Among the widely employed additives in wine production is sulfite (SO2). The popularity of sulfite lies in its ability to preserve the flavor and freshness of wine; however, depending on the quantity, sulfite can pose serious health risks to consumers and affect the quality of the drink. The present study evaluated and compared the compositions of volatile compounds and sensorial properties of sparkling and traditional wines (with and without SO2) produced from Greek grapes 'Grechetto', 'Greco bianco' and 'Greco di tufo'. The results obtained of the composition of volatile compounds in these wines pointed to differences between SO2-containing, SO2-free and sparkling wines, with different amounts of compounds such as alcohols, esters, fatty acids, phenols and differences in sensorial properties. The 'Grechetto' wine, prepared without SO2, exhibited greater quality, better volatile composition, and better sensorial properties compared to the wines produced with SO2. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05160-y.

Assessment of p-aminophenol oxidation by simulating the process of hair dyeing and occurrence in hair salon wastewater and drinking water from treatment plant.

This work reports the study of oxidation reaction of p-aminophenol (PAP) in ammoniacal medium in dissolved atmospheric oxygen and hydrogen peroxide, simulating the process of hair dyeing with permanent dyes. The products formed, which included semi-quinoneimine radical, quinoneimine, dimers, trimers and tetramers, were identified by mass spectrometry, infrared spectroscopy, UV-vis spectrophotometry, and nuclear magnetic resonance of hydrogen. The process was found to involve an autoxidation mechanism. The mutagenicity of the products was carried out by Salmonella Typhimurium YG1041 assay, and the results indicated no mutagenic properties. The presence of PAP and its oxidative products in samples of wastewater collected from hairdressing salon effluent (WW), raw river water (RRW), and water inlet and outlet of drinking water treatment plant (DWTP) was analyzed by HPLC-DAD. PAP was detected in the collected samples of WW, water samples from DWTP (before and after treatment), at concentrations of 2.1 ± 0.5 mg L-1, 1.9 ± 0.3 × 10-3 mg L-1 and 1.3 ± 0.2 × 10-3 mg L-1, respectively. The reaction products, including dimers, trimers and tetramers were identified only in the WW sample; this shows that both the precursor in the sample and its derivatives were released into the wastewater.

Is mortality rate influenced by the site of involvement in neonates undergoing laparotomy for necrotizing enterocolitis?

PURPOSE: The aim of the study was to evaluate the effect of disease site on the mortality rate of newborns with necrotizing enterocolitis (NEC) undergoing exploratory laparotomy. METHODS: The study used prospective cohort of 141 consecutive newborns with NEC who underwent laparotomy from November 1991 to December 2005. RESULTS: One hundred nineteen (84.4%) newborns were premature. Small for gestational age was observed in 57 (40.4%). Sixty-eight (48.2%) infants died. Bivariate analysis revealed that involvement of the jejunum and ileum was associated with high mortality rates (20 deaths; 76.9%; odds ratio [OR], 20; 95% confidence interval [CI], 4.6-96.3; P < .001) and that coinvolvement of the jejunum was associated with greater disease extent. After controlling for individual variables, logistic regression showed that the mortality associated with jejunum and ileum involvement (OR, 0.61; 95% CI, 0.06-6.14; P = .68) did not differ from that associated with large bowel involvement (OR, 2.91; 95% CI, 0.81-10.50; P = .10). When the jejunum was involved with the disease, the percentage of involvement of the entire intestine was 72%, and the mortality rate was 85.1%. When the other bowel segments were involved, the global percentage of disease extent ranged from 42% to 49%, and the mortality rate from 51.9% to 71.8%. After multivariable adjustment disease site, jejunal involvement appeared to be only a surrogate marker of disease extent. CONCLUSIONS: The NEC-related mortality in newborns undergoing laparotomy was not influenced by disease site (small or large bowel). However, jejunum coinvolvement was a marker of greater disease extent and therefore of poor prognosis.

Color Doppler sonography of normal and torsed testicular appendages in children.

OBJECTIVE: The purpose of our study was to determine the size and appearance of normal and torsed testicular appendages on color Doppler sonography. SUBJECTS AND METHODS: Thirty-three patients with acute scrotal pain underwent gray-scale and color Doppler sonography and subsequent surgery. Twenty-two patients had torsion of the appendix testis, six had epididymitis, three had torsion of the testis, and two had torsion of the appendix epididymidis. The testicular appendages of 30 patients and the testes of three were excised and sent to the laboratory for histopathologic examination. RESULTS: A testicular appendage was identified on color Doppler sonography in 23 patients (21 patients with torsed appendages and two patients with epididymitis). The torsed appendixes testis measured from 4.1 to 16.3 mm, and the normal appendixes in the two patients with epididymitis measured 4.1 and 5.6 mm. With the visualization of an appendix larger than 5.6 mm as the sonographic diagnostic criterion for torsion of a testicular appendage, sensitivity was 68.2% (95% confidence interval (CI), 45.1-85.3%), and specificity was 100% (CI, 74.7-100%). CONCLUSION: The identification of a testicular appendage larger than 5.6 mm is suggestive of torsion. Therefore, depending on the patients' clinical conditions, these cases can be treated conservatively when an appendage larger than 5.6 mm is identified.