Pyruvate kinase deficiency in 29 Turkish patients with two novel intronic variants.

Pyruvate kinase (PK) is a key enzyme of anaerobic glycolysis. The genetic heterogeneity of PK deficiency (PKD) is high, and over 400 unique variants have been identified. Twenty-nine patients who had been diagnosed as PKD genetically in seven distinct paediatric haematology departments were evaluated. Fifteen of 23 patients (65.2%) had low PK levels. The PK:hexokinase ratio had 100% sensitivity for PKD diagnosis, superior to PK enzyme assay. Two novel intronic variants (c.695-1G>A and c.694+43C>T) have been described. PKD should be suspected in patients with chronic non-spherocytic haemolytic anaemia, even if enzyme levels are falsely normal. Total PKLR gene sequencing is necessary for the characterization of patients with PKD and for genetic counselling.

A novel MTX2 gene splice site variant resulting in exon skipping, causing the recently described mandibuloacral dysplasia progeroid syndrome.

Until recently, mandibuloacral dysplasia (MAD) with type A and type B lipodystrophy was the first to come to mind in the association of mandibular hypoplasia, lipodystrophy, and acro-osteolysis. However, it has recently been added to the differential diagnosis of MAD, a newly defined syndrome, called MDPS. MDPS is a skeletal dysplasia characterized by postnatal growth retardation, hypotonia, generalized lipodystrophy, skin changes, progeroid traits, and dysmorphic facial features, including prominent eyes, long pinched nose, mandibular hypoplasia, and a small mouth. Biallelic null variants of the MTX2 gene are responsible for this syndrome. We performed whole-exome sequencing (WES) in a 6-year-old patient with skeletal dysplasia. WES revealed a novel homozygous c.543+1G>T splice site variant in the MTX2 gene. We also extracted total RNA from peripheral blood and used reverse transcription-polymerase chain reaction to generate cDNA. Sanger sequencing from cDNA showed that exon 8 of MTX2 was skipped. This study adds to the genetics and phenotype of MDPS and underlines the importance of comprehensive clinical and molecular research.

Change in gene expression levels of GABA, glutamate and neurosteroid pathways due to acoustic trauma in the cochlea.

The characteristic feature of noise-induced hearing loss (NIHL) is the loss or malfunction of the outer hair cells (OHC) and the inner hair cells (IHC) of the cochlea. 90-95% of the spiral ganglion neurons, forming the cell bodies of cochlear nerve, synapse with the IHCs. Glutamate is the most potent excitatory neurotransmitter for IHC-auditory nerve synapses. Excessive release of glutamate in response to acoustic trauma (AT), may cause excitotoxicity by causing damage to the spiral ganglion neurons (SGN) or loss of the spiral ganglion dendrites, post-synaptic to the IHCs. Another neurotransmitter, GABA, plays an important role in the processing of acoustic stimuli and central regulation after peripheral injury, so it is potentially related to the regulation of hearing function and sensitivity after noise. The aim of this study is to evaluate the effect of AT on the expressions of glutamate excitotoxicity, GABA inhibition and neurosteroid synthesis genes.We exposed 24 BALB/c mice to AT. Controls were sacrificed without exposure to noise, Post-AT(1) and Post-AT(15) were sacrificed on the 1st and 15th day, respectively, after noise exposure. The expressions of various genes playing roles in glutamate, GABA and neurosteroid pathways were compared between groups by real-time PCR.Expressions of Cyp11a1, Gls, Gabra1, Grin2b, Sult1a1, Gad1, and Slc1a2 genes in Post-AT(15) mice were significantly decreased in comparison to control and Post-AT(1) mice. No significant differences in the expression of Slc6a1 and Slc17a8 genes was detected.These findings support the possible role of balance between glutamate excitotoxicity and GABA inhibition is disturbed during the post AT days and also the synthesis of some neurosteroids such as pregnenolone sulfate may be important in this balance.

Varied phenotypic spectrum presenting of paroxysmal exercise-induced dyskinesia: a Turkish family with SLC2A1 mutation.

INTRODUCTION: Paroxysmal exercise-induced dyskinesia (PED) is characterized by repeated episodes of involuntary movement disorders that are typically caused by prolonged walking or running and mostly caused by SLC2A1 gene mutations. Phenotypes vary from focal dystonia, ataxia, tremor, and complex non-kinesigenic movements to other movement disorders in patients with SLC2A1 mutation. Also, SLC2A1 mutations carriers may present with also other phenotypes such as epileptic seizure and migraine. CASE REPORTS: We report five patients with various phenotypic spectrums of PED in a Turkish family. Whole exome sequencing revealed a likely pathogenic synonymous variant p.Ser324Ser (c.972G > A) in the SLC2A1 gene (ENST00000426263.3) and the variant segregated in all affected family members. Also, other than PED, the phenotypical spectrum of affected individuals in this family includes epilepsy, mental retardation, and weakness. CONCLUSIONS: We concluded that family members with the same SLC2A1 gene mutation may show very heterogenous phenotypes. Clinicians should be aware of wide variety of symptoms of the patients with PED. We also emphasized that even if a mutation in the coding sequence does not make an amino acid change, it may cause the disease.

Increased vitamin D receptor gene expression and rs11568820 and rs4516035 promoter polymorphisms in autistic disorder.

Although there are a large number of sequence variants of different genes and copy number variations at various loci identified in autistic disorder (AD) patients, the pathogenesis of AD has not been elucidated completely. Recently, in AD patients, a large number of expression array and transcriptome studies have shown an increase in the expression of genes especially related to innate immune response. Antimicrobial effects of vitamin D and VDR are exerted through Toll-Like-Receptors (TLR) which have an important role in the innate immune response, are expressed by antigen presenting cells and recognize foreign microorganisms. In this study, age and gender matched 30 patients diagnosed with AD and 30 healthy controls were included in the study. Comparatively whole blood VDR gene expression and rs11568820 and rs4516035 SNP profile of the promoter region of the VDR gene were investigated by real time PCR. Whole blood VDR gene expression was significantly higher in the AD group compared to control subjects (p < 0.0001). There were no significant differences among allele and genotype distribution of rs11568820 and rs4516035 polymorphisms between AD patients and controls. The increase of VDR gene expression in patients with AD may be in accordance with an increase in the innate immune response in patients with AD. Furthermore, this study will stimulate new studies in order to clarify the relationship among AD, vitamin D, VDR, and innate immunity.

Prenatal diagnosis of upper extremity malformations with ultrasonography: Diagnostic features and perinatal outcome.

OBJECTIVE: The aim of this study was to assess the sonographic (US) characteristics, associated malformations, chromosomal status, and perinatal outcomes of fetuses with an upper extremity malformation (UEM) detected by US examination. METHODS: The data of all patients evaluated in the Department of Obstetrics and Gynecology, Prenatal Diagnosis Unit between 2010 and 2015 were searched for UEM. RESULTS: A total of 51 cases with UEM were detected. Eighteen cases (35.2%) had defects in the formation of body parts (absence of hand/forearm/digits); 25 cases (49%) had defects in differentiation (contractures, syndactyly), and 8 cases (15.6%) had duplication defects (polydactyly). The specificity of prenatal US for UEM was 96.2%. Ten cases (19.7%) had isolated UEM, and 41 cases (80.3%) had additional anomalies, most of which were cardiac, central nervous system, or facial malformations. Although chromosomal structure in isolated cases was normal in 9 of 10 cases (90%), 15 of 41 cases (36.5%) with multiple defects showed abnormal karyotypes. The chromosomal constituents of nine cases (17.6%) were not available. Although the postnatal outcome of isolated cases was favorable except for the presence of orthopedic problems, complex UEMs with or without abnormal karyotypes were always lethal (97.5%). CONCLUSIONS: UEMs associated with other malformations are usually a sign of underlying severe chromosomal abnormalities, and the prognosis is poor. In contrast, chromosomal structure in isolated cases is normal, and the perinatal and postnatal outcomes are good. In general, US is an effective tool in differentiating fetuses with isolated UEM from those with UEM associated with additional malformations. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:267-276, 2017.

A Novel Variant in AKAP9 Gene, a Controversial Gene, in Long QT Syndrome.

Introduction: Long QT syndrome (LQTS) is a common congenital cause of fatal cardiac arrhythmia. Characteristic clinical findings are prolonged QT interval and ventricular arrhythmia on electrocardiogram (ECG), syncope, seizure, and sudden death. It is a genetically heterogeneous disease. To date, disease-causing variant have been reported in seventeen genes. The AKAP9 is still considered controversial among those genes. Case Report: We report the case of a 10-year-old female who was born from a non-consanguineous Turkish couple. She visited pediatrics cardiology clinic presenting with dyspnea and tachycardia. Prolongation of the QT interval was detected in her ECG. Panel test associated with LQTS genes was performed. She was diagnosed with long QTS type 11 due to a heterozygous variant in AKAP9:c.11487_11489 delTACinsCGTA, p.(Thr3830ValfsTer12), that was revealed through next-generation sequencing test. The variant was also found in her mother and brother. Discussion and Conclusion: Novel heterozygous frameshift variant in the AKAP9 gene was considered as "Uncertain Significance (VUS)" in the ACMG classification. The novel variant is absent from population databases (PM2); it is a null variant (PVS1_moderate). AKAP9 gene has the lowest known rate among the causes of LQTS. Information is limited on genotype-phenotype correlation. Yet it is still among the candidate genes. Although the relationship of the AKAP9 gene with LQTS has not yet been fully indicated, individuals with a pathogenic variant in AKAP9 gene and silent carriers may be at risk for fatal cardiac events. Improvements of the genetic tests in the near future may contribute to the literature and clinical research about AKAP9 gene.

EVs vs. EVs: MSCs and Tregs as a source of invisible possibilities.

Extracellular vesicles (EVs) are produced by various cells and exist in most biological fluids. They play an important role in cell-cell signaling, immune response, and tumor metastasis, and also have theranostic potential. They deliver many functional biomolecules, including DNA, microRNAs (miRNA), messenger RNA (mRNA), long non-coding RNA (lncRNA), lipids, and proteins, thus affecting different physiological processes in target cells. Decreased immunogenicity compared to liposomes or viral vectors and the ability to cross through physiological barriers such as the blood-brain barrier make them an attractive and innovative option as diagnostic biomarkers and therapeutic carriers. Here, we highlighted two types of cells that can produce functional EVs, namely, mesenchymal stem/stromal cells (MSCs) and regulatory T cells (Tregs), discussing MSC/Treg-derived EV-based therapies for some specific diseases including acute respiratory distress syndrome (ARDS), autoimmune diseases, and cancer.

Effects of thymoquinone in prevention of experimental contrast-induced nephropathy in rats.

OBJECTIVES: This study aimed to show the effects of thymoquinone, which is known for its antioxidant, anti-inflammatory, and renal protective effects in contrast-induced nephropathy. MATERIALS AND METHODS: This is an experimental study in rats. 7 groups were included within the scope of our study: sham-vehicle (n=3), premedication-control (n=6), model (n=6), isolated thymoquinone (n=3+3), low-dose thymoquinone (n=6), and high-dose thymoquinone (n=7). In addition to 48 hr of water deprivation, we pre-medicated the rats with intra-peritoneal indomethacin and L-NAME administration. After premedication, 12.5 ml/kg dose of a high osmolar contrast agent-diatrizoat (Urografin %76) was administrated. Thymoquinone was administrated in two different doses of 1 mg/kg and 1.75 mg/kg for four days intraperitoneally. Renal functions, histopathological differences, oxidative stress parameters, and inflammatory indicators of rats were evaluated at the end of the study. RESULTS: Significant decreases were observed in levels of serum creatinine and serum BUN with low-dose thymoquinone (1 mg/kg) administration. In light microscopy, significantly less histopathological damage was observed in the low-dose thymoquinone group compared to the contrast agent group. While high-dose thymoquinone is accepted as ineffective biochemically, toxic evidence was identified histopathologically. There were no significant differences between M and TA groups for serum MDA and SOD levels, which were compared to evaluate oxidative stress (P:0.99, P:0.98; respectively). TNF-α, iNOS, and NF-кB gene expressions were not significantly different between all groups (P:0.748, P:0.531, P:0.910; respectively). CONCLUSION: This experimental study has demonstrated for the first time the protective effect of the TQ substance for CIN in 1 mg/kg dose, in the accompaniment of biochemical and histopathological data in rats.