Sibel Kul

CEP152 is a genome maintenance protein disrupted in Seckel syndrome

Functional impairment of DNA damage response pathways leads to increased genomic instability. Here we describe the centrosomal protein CEP152 as a new regulator of genomic integrity and cellular response to DNA damage. Using homozygosity mapping and exome sequencing, we identified CEP152 mutations in Seckel syndrome and showed that impaired CEP152 function leads to accumulation of genomic defects resulting from replicative stress through enhanced activation of ATM signaling and increased H2AX phosphorylation.

Contribution of Diffusion-Weighted Imaging to Dynamic Contrast-Enhanced MRI in the Characterization of Breast Tumors

OBJECTIVE The purpose of our study was to evaluate the diagnostic value of an imaging protocol that combines dynamic contrast-enhanced MRI (DCE-MRI) and diffusion-weighted imaging (DWI) in patients with suspicious breast lesions and to determine if additional information provided by DWI improves the diagnostic value of breast MRI. MATERIALS AND METHODS Eighty-four patients with breast tumors (37 benign, 47 malignant) underwent DCE-MRI and DWI before biopsy. Morphologic and kinetic analyses were performed on DCE-MRI and findings were classified according to the BI-RADS lexicon. Apparent diffusion coefficient (ADC) values were calculated from the DWI. The ADCs of the benign and malignant lesions were compared. For the combined MRI protocol, morphologic kinetic features and ADCs were evaluated together. Diagnostic values of DCE-MRI, DWI, and combined MRI were calculated. RESULTS Median ADCs of the benign and malignant lesions were 1.26 × 10(-3) mm(2)/s and 0.75 × 10(-3) mm(2)/s, respectively. Cutoff value of 0.92 × 10(-3) mm(2)/s for ADC provided 91.5% sensitivity and 86.5% specificity. DCE-MRI alone showed 97.9% sensitivity and 75.7% specificity. The combination of DCE-MRI with DWI provided 95.7% sensitivity and 89.2% specificity. The specificity of breast MRI improved by 13.5% (p = 0.063) without a significant decrease in the sensitivity (p = 1.000). CONCLUSION The combination of DWI and DCE-MRI has the potential to increase the specificity of breast MRI.

MDCT with multiplanar reconstruction in the preoperative local staging of rectal tumor

ObjectiveTo evaluate the accuracy of MDCT with multiplanar reconstruction in the preoperative local staging of rectal tumor.Materials and methodsThirty-seven patients with rectal tumor underwent preoperative MDCT. Two radiologists evaluated the depth of tumor invasion (T staging), regional lymph node involvement (N staging) and mesorectal fascia involvement on axial, sagittal, and coronal multiplanar reconstruction images in consensus. MDCT findings were compared with pathologic results, which served as the reference standard. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were assessed.ResultsOverall accuracy was 86% in T staging, 84% in N staging, 89% in International Union Against Cancer (UICC) Staging, and 94.5% in the prediction of mesorectal fascia involvement.ConclusionMDCT with multiplanar reconstruction is an accurate technique in the preoperative local staging of rectal tumor.

Contrast-Enhanced MR Angiography of the Breast: Evaluation of Ipsilateral Increased Vascularity and Adjacent Vessel Sign in the Characterization of Breast Lesions

OBJECTIVE The purpose of this study was to investigate the role of evaluation of breast vascularity with contrast-enhanced MR angiography in the differentiation of malignant from benign lesions. MATERIALS AND METHODS Contrast-enhanced 3D MR angiograms of the breasts of 102 patients with unilateral and histopathologically confirmed breast lesions were evaluated retrospectively. All images were evaluated for both ipsilateral increased vascularity and adjacent vessel sign, and the values of these signs in the diagnosis of malignancy were assessed. RESULTS Histopathologic analysis of 102 patients revealed 50 malignant and 52 benign results. In 31 of the 50 patients with breast cancer and in 11 of the 52 patients with benign lesions, ipsilateral breast vascularity was increased. The resulting sensitivity and specificity of ipsilateral increased vascularity were 62% and 79%. The adjacent vessel sign was present in 37 of the 50 patients with breast cancer and six of the 50 patients with benign lesions. The resulting sensitivity and specificity of the adjacent vessel sign were 74% and 89%. The overall accuracies of ipsilateral increased vascularity and the adjacent vessel sign were 71% and 81%. CONCLUSION Both ipsilateral increased vascularity and the adjacent vessel sign were found to be associated with breast cancer in a significant percentage of patients. The adjacent vessel sign is more practical and generally applicable. There is a borderline significance in favor of the higher accuracy of the adjacent vessel sign in comparison with ipsilateral increased vascularity (p = 0.043).

Contribution of MRI to ultrasound in the diagnosis of fetal anomalies.

To evaluate the contribution of MRI to ultrasound (US) in the diagnosis of fetal anomalies.

Diagnostic efficacy of the diffusion weighted imaging in the characterization of different types of breast lesions

To evaluate the diagnostic efficacy of quantitative Diffusion‐weighted imaging (DWI) in the characterization of breast lesions of mass and non‐mass enhancement (NME) types.

Diagnostic value of color Doppler ultrasonography and MDCT angiography in complications of hemodialysis fistulas and grafts

PURPOSE The purpose of the study was to compare the diagnostic value of color Doppler ultrasonography (CDUS) and multidetector computed tomography (MDCT) angiography against that of digital subtraction angiography (DSA) or surgery in the evaluation of failing hemodialysis arteriovenous fistulas (AVFs). MATERIALS AND METHODS CDUS and MDCT angiography were performed with 41 patients (24 men, 17 women; mean age 55.8) with dysfunctional hemodialysis fistulas. The presence of stenosis, thrombosis, aneurysm, pseudoaneurysm and seroma were recorded. The sensitivity, specificity, positive and negative predictive values (PPV and NPV) and accuracy of CDUS and MDCT angiography were calculated both individually and in combination for the detection of vascular segments with significant stenosis, thrombosis, aneurysms, pseudoaneurysms, perivascular complications and stenosis subgroups. RESULTS Sixty-four segmental lesions were diagnosed by DSA or surgery. Sensitivity, specificity, PPV, NPV and accuracy of CDUS for all vascular tree lesions were 85.9%, 99.2%, 96.4%, 96.7% and 94.5%, respectively. For MDCT angiography the figures were 96.8%, 99.6%, 98.4%, 99.2% and 98.5%, respectively. When both tests were used in combination, sensitivity, specificity, PPV, NPV and accuracy for all vascular tree lesions rose to 100%. CONCLUSION Combined use of MDCT and CDUS for diagnosis of AVF dysfunctions is of equivalent value to surgery or DSA, a gold standard technique.

The Very Low Density Lipoprotein Receptor–Associated Pontocerebellar Hypoplasia and Dysmorphic Features in Three Turkish Patients

Pontocerebellar hypoplasia consists of a rare heterogeneous group of congenital neurodevelopmental disorders characterized by hypoplasia and atrophy of the cerebellar cortex, dentate and pontine nuclei, and inferior olives. The very low density lipoprotein receptor protein is an integral part of the reelin signaling pathway, which guides neuroblast migration in the cerebral cortex and cerebellum. Mutations in this receptor cause nonprogressive cerebellar ataxia, mental retardation, and cerebellar hypoplasia. In this report, we present 3 patients from 2 different families displaying very low density lipoprotein receptor–associated pontocerebellar hypoplasia, cortical dysplasia, mental retardation, and bipedal gait. One of the siblings has also displayed dysmorphic features, as we previously reported before the identification of the genetic defect in this family.

Umbilical venous catheter complications in newborns: a 6-year single-center experience

Abstract Objective: Umbilical venous catheter (UVC) insertion is frequently performed in critically ill neonates. Various mild or serious complications of umbilical venous catheterization can be observed associated with this procedure. In this study, newborns that have undergone UVC and developed complications were evaluated. Methods: This retrospective observational study was carried out in newborns that have undergone UVC and developed complications were evaluated between June 2008 and November 2014. Results: Umbilical venous catheter were inserted to 974 (22.4%) newborn and followed for 7402/catheter days. UVC-related complications developed at 198 patients (20.3%). The most common UVC-related complications were malposition (n = 189), catheter-related bloodstream infection (n = 6) and remnant of catheter in the umbilicus (n = 3), respectively. Remnant of catheter in the umbilicus was removed by pediatric surgeon. Except one patient, all patients were discharged. Conclusion: Although UVC is a common and easy vascular access, this process is not without complications. UVC may be inappropriate position because the catheter is inserted by the pediatrician without imaging guidance and may occasionally be associated with complications. Inappropriate positioning of the catheter may observe during the follow-up and maintained care. Therefore, newborns particularly in premature and very low birth-weight newborn should be followed in terms of catheter complications during insertion, following and just after removing of the catheter.

Leukoencephalopathy with thalamus and brainstem involvement and high lactate caused by novel mutations in the EARS2 gene in two siblings

Leukoencephalopathy with thalamus and brainstem involvement, and high lactate (LTBL) is a recently identified disease related to mutations in the EARS2 gene encoding glutamyl-tRNA synthetase. We report clinical and radiological findings for two siblings with new pathogenic mutations in the EARS2 gene. Both patients showed symptoms of mild-type disease, but there were clinical differences between the two siblings. While the older brother had hypotonia and delayed developmental milestones, the younger brother had seizures and spasticity in the lower extremities. Brain magnetic resonance imaging (MRI) findings were quite similar for the two siblings. MRI findings were specific to LTBL. MRI lesions of the older sibling had regressed over time. Clinical and radiological improvement, as in the previously reported patients with LTBL, may be an important clue for diagnosis.