Morphometric Shape Analysis of Corpus Callosum in Children With Down Syndrome

Down syndrome (DS) is characterized by varying degrees of mental retardation and delay in neurocognitive functions. Herein, we analyzed the morphometric shape of the corpus callosum (CC) in children with DS. Twenty-three DS cases underwent magnetic resonance imaging and have grossly normal CC, and 23 control group cases were included in this retrospective study (2012-2020). The CC was obtained from T2-weighted mid-sagittal images, and certain anatomical points were marked on the CC. Statistical geometric shapes and deformations of CC were evaluated for both groups. The age range of patients with DS and control group was 6 to 42 months. A statistically significant difference was found in the shape of CC between the groups (P < .001). Deformation was most evident in the splenium in the DS group.

Higher TP53 somatic mutation prevalence from liquid biopsy analysis in ever smoker non-small-cell lung cancer patients

OBJECTIVE

Cigarette smoking is a primary risk factor, linked to 80% of LC deaths. TP53, a key gene, is implicated in various cancers, with TP53 alterations in 36.7% of cancers. This research aims to investigate TP53 mutations detected in NSCLC patients by liquid biopsy and explore the relationship between these mutations and smoking history.

MATERIAL AND METHOD

The study enrolled a total of 340 patients diagnosed with non-small cell lung cancer (NSCLC). For sequencing, the Illumina NextSeq 500 system was utilized. The oncogenicity of the variants was assessed according to the ClinGen/CGC/VICC SOP and the variants were categorized into four tiers according to AMP/ASCO/CAP.

RESULTS

The most common mutations were in TP53 (48.7%), followed by EGFR, PIK3CA, and PTEN. Missense mutations were frequent, with TP53 and EGFR having higher rates in ever-smokers. No indels or complex mutations were found in ever-smokers. Patient age ranged from 20 to 86 years. Tier I-II variants were more common in ever-smokers, while Tier III variants were prevalent in never-smokers. TP53 mutations were more frequent in ever-smokers, showing a strong association with smoking. Domain distribution showed differences in PIK3CA. Transversion/transition ratios varied by gene and smoking status.

DISCUSSION

The presence of TP53 mutations is strongly associated with both cigarette smoking and elevated Tv/Ti ratios. The tier status of TP53, EGFR, and PTEN variants does not show a specific domain distribution, but interesting associations are observed between the tier status and domain distribution in PIK3CA variants. Therefore, further comprehensive investigations are needed to explore this entity, as well as the underlying factors contributing to the increased Tv/Ti rates in the TP53 gene. Such research will provide deeper insights into the genetic alterations associated with smoking and tumor heterogeneity, ultimately aiding in the development of targeted therapies.

Investigation of the protective effects of intraperitoneal melatonin in rats receiving laryngeal radiotherapy

OBJECTIVES

To examine the protective effects of melatonin on laryngeal radiation damage.

MATERIALS AND METHODS

31 rats were divided into 4 groups as follows: 1) the control (C) group (n=7), was only injected with intraperitoneal ethanol solution; 2) the melatonin (M) group (n=8), was injected intraperitoneal melatonin solution with 5 mg/kg; 3) the radiotherapy (RT) group (n=8) was given laryngeal radiation after intraperitoneal injection of ethanol solution; 4) the M + RT group (n=8), RT was given 30 minutes after 5 mg/kg dose of melatonin solution was injected. Drug and radiation applications were continued for 5 days. The weight changes of the rats were recorded. At the end of the study, inflammation, neutrophil migration and lymphoid aggregates, collagen distribution, laryngeal glandular structures and biochemical analysis of laryngeal tissues [malondialdehyde (MDA), total oxidant status (TOS) and total antioxidant status (TAS)] were determined.

RESULTS

In the M+RT group, the first day and the 30th weight differences were significantly increased when compared with the RT group (p=0.050). Inflammation, neutrophil migration, lymphoid aggregate, disorganized collagen distribution and loss of glandular tissues were found statistically more in the RT group than in the C group (p<0.05). MDA and TOS levels were in the M + RT group exhibited better values than they did in the RT group (p<0.05). TAS levels was markedly increased in the M + RT group than in the RT group (p<0.001).

CONCLUSION

Administration of melatonin to rats prior receiving laryngeal radiation, decreases the level of oxidative stress markers and increases the level of anti-oxidative markers.

Molecular Approach of Hereditary Arrhythmias, Long QT Syndrome, and Arrhythmogenic Right Ventricular Cardiomyopathy

Background:

Hereditary cardiac arrhythmias result from mutations in various genes encoding ion channels. One major channelopathy is long QT syndrome, which has excellent genetic and clinical heterogeneity. Arrhythmogenic right ventricular cardiomyopathy, another hereditary arrhythmia type, also shows high genetic heterogeneity and variable expressivity. Next-generation sequencing is an effective tool to reveal the disease’s underlying genetic etiology.

Methods:

In this study, we performed clinical exome sequencing or gene panel including cardiac arrhythmia and cardiomyopathy-associated genes by next-generation sequencing in 13 unrelated patients.

Results:

Five pathogenic or likely pathogenic mutations, including three novel mutations, were found in the total cases.

Conclusion:

This research shows a strong genetic heterogeneity in the disease. In addition, the study revealed that patients with QT interval prolongation on electrocardiogram might also have mutations in genes that are not associated with long QT syndrome, such as MYLK2 and DSG2. Therefore, our data helped expand the molecular scope of long QT syndrome. It is necessary to study with a broad perspective to elucidate the underlying molecular etiology in patients with hereditary cardiac arrhythmias.

Is there association between QRS-T angle, and hormonal and sonographic features in polycystic ovarian syndrome?

OBJECTIVE

Polycystic ovary syndrome (PCOS) is a complex disorder comprising ovulatory dysfunction, hyperandrogenism, and polycystic ovaries (PCO). Several studies have used electrocardiography (ECG) to assess PCOS patients. We aimed to analyze the associations among QRS-T angle, hormonal parameters, and ovarian and thyroid sonography in PCOS.

PATIENTS AND METHODS

Adult females with PCOS, but without comorbid illness, were included in our study. Demographic and clinical features (body mass index, Ferriman-Gallwey score, phenotype) were analyzed, as well as laboratory test results. Based on standard 12-lead ECGs, frontal plane QRS-T angles were calculated, defined as the angle between the mean QRS and the mean T vector, and verified with automatic instrument measurements. Values within the range -46 to +59° were classified as "normal", and those out of this range as "abnormal". Patients were divided into groups according to the presence of thyroid nodules, echogenicity (normal/decreased), and vascularity (normal/increased) based on thyroid sonography, and by mean ovarian volume (MOV ≥ 10/< 10 mL) or apparent PCO based on ovarian sonography.

RESULTS

The mean age of the 92 patients was 22.68 ± 4.58 years; 11 patients (11.9%) had abnormal QRS-T angles. Demographic, clinical, electrocardiographic, and laboratory parameters were similar between the normal and abnormal QRS-T angle groups, with the exception of MOV, which was higher in the latter group (p=0.032). Among all clinical and laboratory parameters, only MOV was a strong predictor of abnormal QRS-T angle (p=0.016).

CONCLUSIONS

Our study is the first to analyze the association between the QRS-T angle and hormonal and sonographic features of patients with PCOS. A small percentage of patients had abnormal QRS-T angles, and a large MOV was a strong predictor of this abnormality.

SMN1 gene copy number analysis for spinal muscular atrophy (SMA) in a Turkish cohort by CODE-SEQ technology, an integrated solution for detection of SMN1 and SMN2 copy numbers and the "2+0" genotype

INTRODUCTION

Spinal muscular atrophy (SMA) is one of the common autosomal recessive disorders with global heterozygous carrier frequency of 1:50. Due to high carrier frequency, significant morbidity associated with the infantile onset disease and prohibitive cost of recently approved therapy, American College of Medical Genetics and Genomics (ACMG) recommends population based screening for SMA carrier status in eligible individuals in the reproductive age group. CODE-SEQ is a novel proprietary next generation sequencing (NGS) based assay, which is capable of detecting homozygous as well as heterozygous SMN1 exon 7 deletions. Along with the copy number estimation, this assay is capable of detecting single nucleotide polymorphisms (SNPs) associated with silent SMA carrier status or "2+0" genotype.

METHODS

We have validated a proprietary CODE-SEQ technology in a blinded cohort of 80 clinically well characterized samples from Turkish population for the detection of SMA carriers as well as affected cases. The results were correlated with gold standard MLPA assay.

RESULTS

The copy numbers in exon 7 of SMN1 gene matched with MLPA results in all 80 samples giving 100% correlation. The assay accurately detected the presence/ absence of SNPs associated with "2+0" genotype in the reference samples. None of the tested clinical samples had these SNPs.

CONCLUSION

The results of this study support the notion that CODE-SEQ will be extremely useful in detecting SMA genotypes in large-scale population-based screening studies.

Novel Mutations in Obesity-related Genes in Turkish Children with Non-syndromic Early Onset Severe Obesity: A Multicentre Study

OBJECTIVE

Non syndromic monogenic obesity is a rare cause of early onset severe obesity in the childhood period. This form may not be distinguishable from other forms of severe obesity without genetic analysis, particularly if patients do not exibit any physical abnormalities or developmental delay. The aim of this study was to screen 41 different obesity-related genes in children with non-syndromic early onset severe obesity.

METHODS

Children with severe (body mass index-standard deviation score >3) and early onset (<7 years) obesity were screened by next-generation sequencing based, targeted DNA custom panel for 41 known-obesity-related genes and the results were confirmed by Sanger technique.

RESULTS

Six novel variants were identified in five candidate genes in seven out of 105 children with severe obesity; two in SIM1 (p.W306C and p.Q36X), one in POMC (p.Y160H), one in PCSK1 (p.W130G fs Ter8), two in MC4R (p.D126E) and one in LEPR (p.Q4H). Additionally, two previously known variations in MC4R were identified in four patients (p.R165W in three, and p.V166I in one).

CONCLUSION

We identified six novel and four previously described variants in six obesity-related genes in 11 out of 105 childrens with early onset severe obesity. The prevalence of monogenic obesity was 10.4% in our cohort.

Kinetics of Supercritical Drying of Gels

Supercritical drying of gels is considered as the most important step of aerogel production since it enables preservation of the three-dimensional pore structure which lead to unique material properties such as high porosity, low density, and large surface area. An understanding of the kinetics of supercritical drying is necessary to provide insight into material development, scale-up, and optimization of the aerogel manufacturing process. Thus, investigation of supercritical drying is gaining increased attention in recent years. This review paper covers the experimental considerations and techniques to study the kinetics of supercritical drying, fundamental mass transfer mechanisms during the drying process and modeling efforts to predict the drying kinetics for varying operating conditions and gel properties. Transport phenomena involving diffusion, convection, spillage by volume expansion, and axial dispersion are discussed by providing the fundamental equations and empirical correlations to predict transfer coefficients. A detailed review of literature covering experimental and theoretical studies on kinetics of supercritical drying is presented.

Out-of-Reference Range Thyroid-Stimulating Hormone Levels in Levothyroxine-Treated Primary Hypothyroid Patients: A Multicenter Observational Study

OBJECTIVE

Although levothyroxine (LT4) replacement therapy for hypothyroidism has been established as safe, inexpensive and effective, many studies from different countries reported out-of-reference range thyroid-stimulating hormone (TSH) values for the hypothyroid patients under LT4 treatment. The aim of this study was to determine TSH levels of primary hypothyroid patients under LT4 treatment and to assess self-reported compliance with daily LT4 intake in tertiary care centers in Turkey.

DESIGN

In this cross-sectional, observational study, adult patients with primary hypothyroidism, receiving LT4 treatment for at least 6 months, were included. The patients were from 12 tertiary care centers in 9 cities of Turkey. TSH and free T4 levels were recorded from patient files and self-reported compliance with daily LT4 intake was assessed by interviewing the subjects at the last visit.

RESULTS

A total of 1,755 subjects (46 ± 13 years; F/M: 89.9/10.1%) with primary hypothyroidism were enrolled. Of the hypothyroid subjects, 44.8% had out-of-reference range serum TSH levels. TSH values were over the reference range (TSH > 4 mIU/L) in 26.2% and were under the reference range (TSH < 0.5 mIU/L) in 18.6% of the patients. Total duration of LT4 treatment was 5.9 ± 4.7 years and mean dose was 1.2 ± 0.6 μg/kg/day. Non-compliant patients (31.1%) had higher TSH levels (6.9 ± 16 vs 3.8 ± 0.9 mIU/L, P = 0.01) compared to compliant patients.

CONCLUSION

The results of this study revealed that nearly half of the hypothyroid patients had out-of-reference range serum TSH values, despite under LT4 treatment. Compliance with LT4 treatment seems to be one of the major determinants to reach the target TSH levels in hypothyroid patients.

Vitamin D receptor gene BsmI, FokI, ApaI, TaqI polymorphisms and bone mineral density in a group of Turkish type 1 diabetic patients

Previous studies have suggested an influence of vitamin D receptor alleles on bone metabolism and on susceptibility to type 1 diabetes mellitus in different ethnic populations. We aimed to investigate the distribution of vitamin D receptor (VDR) alleles in relation to biochemical bone turnover parameters and bone densitometry measurements in a group of Turkish type 1 diabetic patients. One hundred and seventeen patients (M/F 57/60, 27.6 ± 7.3 y duration of diabetes 8.1 ± 6.3 y) and 134 healthy controls (M/F 61/73, 26.2 ± 5.3 y) were included in the study. Bone mineral density (BMD) was evaluated by dual-energy X-ray absorptiometry (DEXA). The vitamin D receptor gene (VDR) polymorphisms FokI, Bsm1, Apa1, and Taq1 were examined using a PCR-based restriction analysis. Serum levels of calcium, phosphor osteocalcin, intact parathyroid hormone, and C telopeptide were measured. Vitamin D receptor Bsm1 Fok1, Apa1, and Taq1 genotype distributions were not different between patient with diabetes and control groups. BMD was 0.77 ± 0.2 g/cm(2) vs. 0.97 ± 0.2 g/cm(2) (P = 0.0001) for the femur, 1.0 ± 0.1 g/cm(2) vs. 1.13 ± 0.1 g/cm(2) (P = 0.001) for type 1 diabetic patients and controls. Bone turnover markers were significantly lower in type 1 diabetic group. BMD measurements and bone metabolic markers were not different between the genotypes in either the patient with diabetes or the controls. The VDR gene polymorphisms, Bsm1, Fok 1, Apa1, and Taq1 showed no influence on bone metabolism in our group of type 1 diabetic patients.