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Backgrounds: Genetic variants in CF transmembrane conductance regulator (CFTR) gene causes cystic fibrosis (CF), a prevalent autosomal recessive disorder. More than 2000 variants in CFTR have been described as disease causative. This study aims to delineate the genotypic and phenotypic landscape of CF among people with CF (pwCF) followed at the largest CF center in Turkey., Methods: We conducted a descriptive and retrospective analysis of 481 patients registered with the European CF Society Patient Registry and followed at Marmara University Selim Çöremen CF Center from 2015 onwards. Comprehensive CFTR analysis was utilized for genetic diagnosis. Besides the whole cohort, novel variants and complex alleles were also described., Results: Our cohort exhibited a broad spectrum of CFTR variants, with 136 different variants detected, indicating substantial genetic diversity. The F508del variant was less prevalent in our cohort compared to US and European averages, which could reflect unique genetic and demographic characteristics of the Turkish population. Additionally, we identified nine novel variants in 12 alleles, which enhances the understanding of CF's genetic complexity in this region, and complex alleles in 32 pwCF., Conclusion: Our research underscores the heterogeneity of CFTR variants in Turkey and highlights the necessity for extensive genetic profiling particularly for diverse populations to provide effective personalized treatment strategies. It is crucial to understand the full spectrum of CFTR variants with the advent of CFTR modulators., (© 2024 The Author(s). Pediatric Pulmonology published by Wiley Periodicals LLC.)

Background: Cystic fibrosis (CF) is an autosomal recessive disease caused by variants of CFTR gene. Over 2000 variants have been identified, and new drugs called CFTR modulators have been developed to target specific defects in the CFTR protein. However, these drugs are only suitable for patients with certain variants of CFTR, and eligibility rates vary depending on race and geographical region. This study aimed to reveal the detailed genotype and clinical characteristics of people with CF (pwCF) at our center in Turkey, a developing country, who are not eligible for CFTR modulators., Methods: A total of 445 pwCF followed up at Marmara University were reviewed retrospectively. Variants of the patients ineligible to CFTR modulators were classified based on American College of Medical Genetics guidelines, CFTR classification, the change in the encoded protein, and the variant type., Results: The study revealed that 139 (31.2%) patients weren't eligible for CFTR modulators. There were 60 different variants in the 276 alleles, as two were missing. The majority of patients had missense or nonsense variants, and that the most common variant was c.1545_1546del, which can be said unique to this geography., Conclusion: The study highlights the importance of detecting the variants of ineligible patients in detail to guide future approaches for more targeted and effective interventions in CF care. Testing the effectiveness of CFTR modulators for rare or newly occurring variants is crucial to ensure equal access for pwCF to these therapies from different racial backgrounds and ethnic minorities., (© 2024 The Author(s). Pediatric Pulmonology published by Wiley Periodicals LLC.)

Objective: Central sleep apnea (CSA) is a rare condition in children; however, it can cause significant morbidity if not diagnosed early. We aimed to increase the knowledge about CSA in children by describing the clinical characteristics of children diagnosed with CSA at our sleep center., Material and Methods: We retrospectively reviewed 1263 polysomnographies (PSG) performed between 2012 and 2023 at our tertiary sleep center and evaluated the clinical characteristics of the patients with CSA. Underlying diseases, clinical symptoms, sleep parameters, and short-term management of the patients were recorded., Results: Of the 1263 patients aged between 1 month and 18 years, 122 (9.65%) had CSA, with 54.9 % (n = 67) of them being female. Only 56.6% (n = 69) of the patients' parents had reported a symptom indicating sleep-disordered breathing. The most common underlying disease was genetic, including Down and Prader-Willi syndromes, followed by neurological diseases . Obstructive sleep apnea was detected in addition to CSA in 103 of the patients (84.4%). Bi-level positive airway pressure with a backup rate was the most common treatment modality., Conclusion: While CSA is a rare clinical condition in children, it occurs more commonly in those with an underlying disease. Awareness of the disease and timely referral of the patients for sleep studies are critical to prevent long-term sequelae.

Because of the hydrophobic nature of the membrane lipid bilayer, the majority of the hydrophilic solutes require special transportation mechanisms for passing through the cell membrane. Integral membrane transport proteins (MTPs), which belong to the Major Intrinsic Protein Family, facilitate the transport of these solutes across cell membranes. MTPs including aquaporins and carrier proteins are transmembrane proteins spanning across the cell membrane. The easy handling of microorganisms enabled the discovery of a remarkable number of transport proteins specific to different substances. It has been realized that these transporters have very important roles in the survival of microorganisms, their pathogenesis, and antimicrobial resistance. Astonishing features related to the solute specificity of these proteins have led to the acceleration of the research on the discovery of their properties and the development of innovative products in which these unique properties are used or imitated. Studies on microbial MTPs range from the discovery and characterization of a novel transporter protein to the mining and screening of them in a large transporter library for particular functions, from simulations and modeling of specific transporters to the preparation of biomimetic synthetic materials for different purposes such as biosensors or filtration membranes. This review presents recent discoveries on microbial membrane transport proteins and focuses especially on formate nitrite transport proteins and aquaporins, and advances in their biotechnological applications., (© 2024. The Author(s).)

nirC gene coding for the nitrite channel of E. coli K12 was cloned into the pET28a vector and expressed in E. coli BL21 cells. 28.5 kDa NirC monomer was purified from membrane components of E. coli. Selectivity of NirC for different ions including nitrite, nitrate, sulfate, formate, and acetate anions, and a divalent cation, magnesium, was compared with that of bacterial aquaporin from Halomonas elongata. Water and ion permeability values were determined by measuring the light scattering rates of proteoliposomes containing NirC and aquaporins during their water loss and gain. NirC shows a selective permeability to nitrite and is more resistant to the entry of other anions as compared to aquaporin. The single channel permeability of NirC for nitrite is about 10-fold that of a single aquaporin channel. Both aquaporin and NirC channel proteins were impermeable to MgCl 2 and (NH 4 ) 2 SO 4 and their permeability to other tested ions was remarkably lower as compared to nitrite ions. The study also presents the 3D model and channel characteristics of NirC. The translocation channel of E. coli NirC is determined to be larger, and its length is shorter than aquaporin channels. Although the NirC channel throat is more hydrophobic than aquaporin, its water permeability is almost equal to that of aquaporin. The hydrophobic nature of the NirC channel might play an important role in the selective permeability of the channel for nitrite ions., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

The assimilatory nitrite reductase enzyme NirB and small subunit NirD genes encoded in nir operon in Escherichia coli were cloned into the pET28a vector, and the recombinant enzyme was characterized for the first time. Docking of NirB with NirD, NADH, NO 2 - , NO 3 - , and CHO 2 - was performed using docking modeling programs. Methyl viologen and sodium dithionite were used as electron couples, and the amount of reduced nitrite was measured to calculate enzyme activity. NirB is the main enzyme and shows high activity with or without NirD. However, the inclusion of NirD into the enzyme solution at a ratio of 1NirD:2NirB resulted in 10% higher nitrite reductase activity. The enzyme tends to aggregate in the absence of β-mercaptoethanol, which causes the conversion of tetrameric NirB to monomeric form, and the NirB enzyme shows its highest activity in monomeric form. The optimum temperature for enzyme activity was 37 °C and the optimum pH was found to be 7.0. K m and V max values of NirB were calculated as 9833 μM and 416.67 μmol NO 2 - reduced min -1 mg -1 . Enzyme activity decreased by 55% and 50% in the presence of 100 mM nitrate and formate, respectively. The presence of 25 mM Cd 2+ protected the enzyme at room temperature and the enzyme showed 10% higher activity in the presence of cadmium., (Copyright © 2022 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Nitrogen oxide (NOx) emissions cause significant impacts on the environment and must therefore be controlled even more stringently. This requires the development of cost-effective removal strategies which simultaneously create value-added by-products or energy from the waste. This study aims to treat gaseous nitric oxide (NO) by hollow-fibre membrane biofilm reactor (HFMBfR) in the presence of nitrite ( NO 2 - ) and evaluate nitrous oxide (N 2 O) emissions formed as an intermediate product during the denitrification process. Accumulated N 2 O can be utilised in methane oxidation as an oxidant to produce energy. In the first stage of the study, the HFMBfR was operated by feeding only gaseous NO as the nitrogen source. During this period, the best performance was achieved with 92% NO removal efficiency (RE). In the second stage, both NO gas and NO 2 - were supplied to the system, and 91% NO and 99% NO 2 - reduction were achieved simultaneously with the maximum N 2 O generation of 386 ± 31 ppm. Lower influent carbon to nitrogen (C/N) ratios, such as 4.5 and 2.0, and higher NO 2 - -N loading rate of 158 mg N day -1 favoured N 2 O generation. An improved NO removal rate and N 2 O accumulation were seen with the increasing amount of PO 4 3 - in the medium. The 16S rDNA sequencing analysis revealed that Alicycliphilus denitrificans and Pseudomonas putida were the dominant species. The study shows that an HFMBfR can be successfully used to eliminate both NO 2 - and gaseous NO and simultaneously generate N 2 O by adjusting the system parameters such as C/N ratio, NO 2 - and PO 4 3 - loading.

Introduction: Little is known about the COVID-19 disease characteristics and differences between different pediatric age groups. This study aimed to investigate the disease characteristics according to age groups., Methodology: We conducted a retrospective, single-center study of pediatric COVID-19 in a tertiary care hospital in Turkey. The patients were divided into three groups: 15 days-24 months old (Group 1), 25-144 months old (Group 2), and 145-210 months old (Group 3) according to age., Results: A total of 139 pediatric patients with COVID-19 were examined. Twenty-nine patients (20.9%) were in Group 1, 52 (37.4%) were in Group 2, 58 (41.7%) were in Group 3. Thirty-nine patients (28.1%) were hospitalized. The most common symptoms were cough (55.4%) and fever (51.8%). The median chest X-ray (CXR) score of hospitalized patients was 1 (min 0-max 7), and the median CXR score of outpatients was 1 (min 0-max 6). Fever was significantly more frequent in Group 1, and chest pain was more frequent in Group 3. Group 1 had significantly higher WBC, lymphocyte, thrombocyte counts, AST, LDH, D-dimer, and Troponin T levels but lower hemoglobin, total protein, and albumin levels. The treatment included antibiotics, oseltamivir, hydroxychloroquine, and supportive therapy. Only one patient (0.7%) received non-invasive mechanical ventilatory support., Conclusions: As we know the clinical course of COVID-19 in children is less severe than in adults. We also found significant differences in both clinical and laboratory findings between different pediatric age groups which supports the theory that disease pathogenesis is highly variable according to age., Competing Interests: No Conflict of Interest is declared, (Copyright (c) 2022 Eda Kepenekli, Nurhayat Yakut, Zeynep Ergenc, Omer Aydiner, Rabia Can Sarınoglu, Aysegul Karahasan, Elif Karakoc-Aydiner, Asli Memisoglu, Yasemin Gokdemir, Ela Erdem Eralp, Pinar Ergenekon, Bulent Karadag, Kubra Gokce Tezel, Murat Aydin, Betul Senyurek, Perran Boran.)

Aim: This study aims to reveal the problems faced by families of children with spinal muscular atrophy (SMA), by evaluating their care burden, needs, and expectations., Materials and Methods: The participants were the primary caregivers of 34 children between the ages of 0 and 18 years diagnosed with SMA. Thirteen children were diagnosed with type 1, 13 children with type 2 and 8 children with type 3 SMA. Data on the medical history, functional levels of the participants, and the characteristics of families were collected. The childrens' parents completed the Family Needs Survey and the Zarit Caregiver Burden Scale., Results: According to the results of the Family Needs Survey, it was found that information was the most common requirement, and this was independent of the level of education. According to the Caregiver Burden Scale, it was recorded that 64.7% of the caregivers were under mild/moderate burden. While there was a moderate correlation ( r = 0.574; P < .001) between the Caregiver Burden Scale and the Family Needs Survey, it was observed that the functional level of the child was not associated with family needs and caregiver burden., Conclusions: Our study suggests that the needs of families of SMA patients, especially related to income level, have changed. The caregivers' burden is not directly related to the income level or the functional level of the child. Families' need for information should also be prioritized within the rehabilitation program., Competing Interests: Conflict of Interest: The authors have no conflict of interest to declare., (© Copyright 2021 by The Turkish Archives of Pediatrics.)

Applications of molecular techniques to elucidate identity or function using biomarkers still remain highly empirical and biosensors are no exception. In the present study, target-specific oligonucleotide probes for E. coli K12 were designed thermodynamically and applied in an electrochemical DNA biosensor setup. Biosensor was prepared by immobilization of a stem-loop structured probe, modified with a thiol functional group at its 5' end and a biotin molecule at its 3' end, on a gold electrode through self-assembly. Mercaptopropionic acid (MPA) was used to optimize the surface probe density of the electrode. Hybridization between the immobilized probe and the target DNA was detected via the electrochemical response of streptavidin-horseradish peroxidase in the presence of the substrate. The amperometric response showed a linear relationship with the target DNA concentration, ranging from 10 and 400 nM, with a correlation coefficient of 0.989. High selectivity and good repeatability of the biosensor showed that the thermodynamic approach to oligonucleotide probe design can be used in development of electrochemical DNA biosensors., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this study, effect of affinity tags, Histidine (His) and Glutathione-S-Transferase (GST), on the activity of halophilic aquaporin was analyzed. The gene coding for H. elongata aquaporin was cloned into pET28a vector and expressed in E. coli BL21 successfully. Stopped flow light scattering measurements showed that His-tagged aquaporin is functional. The difference in the filtration parameters caused by affinity tags were determined by using thin film composite nano-filtration (NFC) membranes prepared with the aquaporins. At 100 mM salt concentration, water permeability (L/m 2 .h) and the % salt rejection of NFC membranes produced with the His-tagged aquaporin was found to be higher than that of the membrane with GST-tagged aquaporin. Salt rejection of His-tagged aquaporin-membrane was found to be 53% with a lower solute permeability value (B). Use of short affinity tag (His tag) for cloning resulted in higher solute rejection ability of TFC membranes prepared with H. elongata aquaporins., (Copyright © 2020 Elsevier Inc. All rights reserved.)

An extensive monitoring study of volatile organic compounds (VOCs) was conducted at sites across the highly industrialized town of Dilovasi, northern Turkey to determine temporal and spatial trends in pollutant concentrations and relate to the effects of source locations, meteorology, and topography. Two-week passive samplers (Tenax tubes) were deployed at twelve sites from February to December 2012 and analysed using thermal desorption and gas chromatography with mass spectrometric detection (TD-GC-MS). Sampled total VOC (TVOC) levels were highest in the July through October period and were highest at low-altitude sites near industry facilities and vehicle traffic sources (148.3 µg/m(3) at site 11, 154.1 µg/m(3) at site 10) and lowest at high-altitude sites located furthest upwind from industry and traffic sources (78.4 µg/m(3) at site 5 and 78.5 µg/m(3) at site 6). Analysis of "T/B" ratios suggested that contributions to ambient VOC in Dilovasi are dominated by the town's industrial sources. Meteorological conditions and the town's basin topography were also found to significantly influence the city's air quality, with strong winds from the NE observed to correlate with periods of higher sampled TVOC. Compared with other industrialized urban centers, the study revealed that there is significant toluene pollution in Dilovasi and recommended enhanced continuous monitoring at the city's industrial and residential zones.

This article introduces a simple, rapid, and reliable solid-phase microextraction (SPME) method coupled with GC-MS for the quantitative determination of 16 polycyclic aromatic hydrocarbons in water. In this study, the Taguchi experimental design was used to optimize extraction conditions of polycyclic aromatic hydrocarbons using SPME method to obtain highly enriched analytes. Consequently, quantitative determination of polycyclic aromatic hydrocarbons in water was achieved by GC-MS technique. The selected parameters affecting enrichment of polycyclic aromatic hydrocarbons were sample extraction time, stirring speed, temperature, ionic strength, and pH. The study revealed that optimal operating conditions were found to be 90-min extraction time, 1400 rpm stirring speed, and 60°C sample temperature. The effect of ionic strength and pH were shown to be insignificant. Optimized conditions were also reevaluated by placing the 16 polycyclic aromatic hydrocarbons into several subgroups based on their molecular weight. The extraction efficiency of polycyclic aromatic hydrocarbons with low molecular weight was shown to be a function of only the extracting temperature. Satisfactory results were obtained for linearity (0.983-0.999), detection limits (2.67-18.02 ng/L), accuracy (71.2-99.3%), and precision (4.3-13.5%). The optimum conditions reported by other design approaches were evaluated and generalized optimum conditions were suggested., (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)