Large deletions in the polycystic kidney disease 1 (PKD1) gene

Since identification of the genes mutated in patients with Autosomal Dominant Polycystic Kidney Disease, PKD1 and PKD2, a large number of different germ line mutations in both genes have been found by conventional PCR-based mutation detection methods. Nevertheless, in approximately 40% of the PKD1 families the disease-causing mutation remains to be elucidated. Complex germ line rearrangements are often not detectable by these standard diagnostic techniques. To detect large deletions in the PKD1 gene we performed Field Inversion Gel Electrophoresis (FIGE) followed by Southern blot analysis with probes selected in the unique and in the reiterated region of this gene. Our analysis revealed 4 deletions in 125 patients, indicating that large deletions in PKD1 are rare. Likely, patients with a deletion that also affects the neighbouring Tuberous Sclerosis Complex 2 (TSC2) gene will be diagnosed as patients with tuberous sclerosis. It was speculated that the exceptional polypyrimidine tract located in intron 21 and the small tract in intron 22, might play a role in the pathogenesis of ADPKD. Since this region is extremely difficult to amplify by PCR, we analysed the 5.8 kb BamHI fragment that contains the polypyrimidine tracts. We did not observe a disease-linked alteration although we detected two different rare variants either in PKD1 or in one of its homologues.     

Malignant pancreatic tumour within the spectrum of tuberous sclerosis complex in childhood

A 12-year-old boy with tuberous sclerosis complex (TSC) presented with a large retroperitoneal tumour. Exploratory surgery revealed an infiltrative tumour originating from the pancreas, with local metastases to the lymph nodes. The histologal diagnosis was a malignant islet cell tumour. Retrospectively measured pancreatic hormone levels, however, were normal. A connection between the malignancy and TSC was demonstrated by loss of heterozygosity of the TSC2 gene in the tumour. The primary mutation Q478X in this patient was identified in exon 13 of the TSC2 gene on chromosome 16. Conclusion Pancreatic islet cell tumours have been mainly associated with multiple endocrine neoplasia syndrome type 1. In our case we demonstrate a direct relationship of this tumour to tuberous sclerosis complex, in the absence of further signs of multiple endocrine neoplasia syndrome type 1. Received: 17 February 1998 / Accepted in revised form: 8 July 1998     

Evaluation of 3 Different Retreatment Techniques in Maxillary Molar Teeth by Using Micro–computed Tomography

Introduction

Nonsurgical retreatment procedure involves the complete removal of the previous filling material to allow thorough instrumentation, disinfection, and refilling of root canal system. We aimed to determine the residuals of the root-filling material by using 3 different retreatment techniques with the aid of micro–computed tomography.

Long-Term Results of an Imperforate Hymen Procedure that Leaves the Hymen Intact

Purpose of the StudyThe aim of this study was to show the clinical results of postoperative evaluation of cases of imperforate hymen that presented at our center during a 21-year period.MethodsA Foley’s catheter was inserted in 74 patients of imperforate hymen who reported to the Department of Obstetrics and Gynecology, Meram Faculty of Medicine, Necmettin Erbakan University, between January 1, 1996, and December 31, 2016 with history of pelvic pain. In each case, the hymen was opened via a circular incision from the central of the distended. A Foley’s catheter was inserted, and estrogen cream was prescribed for application on the hymenal structure for 14 days. The catheter was removed after 14 days.ResultsThe mean age of the patients at the time of this study was 28.3 ± 2.6 years, and the mean age at diagnosis was 13.2 ± 2.5 years. Twenty-nine (96.6%) patients had experienced vaginal bleeding during their first sexual intercourse experience, and one patient (3.4%) had not. Fourteen out of the 30 married women had become pregnant, of whom nine had delivered vaginally and five had delivered via a cesarean section. After undergoing renal ultrasound, none of the patients had any apparent anomalies. Only one patient had a uterine anomaly, which was a bicornuate uterus.ConclusionA circular incision with insertion of Foley’s catheter prevents many social problems by preserving the hymen’s architecture and allowing vaginal bleeding to occur during the first sexual intercourse experience.     

Combined Monte Carlo and finite-difference time-domain modeling for biophotonic analysis: implications on reflectance-based diagnosis of epithelial precancer

Monte Carlo (MC) modeling of photon transport in tissues is generally performed using simplified functions that only approximate the angular scattering properties of tissue constituents. However, such approximations may not be sufficient for fully characterizing tissue scatterers such as cells. Finite-difference time-domain (FDTD) modeling provides a flexible approach to compute realistic tissue phase functions that describe probability of scattering at different angles. We describe a computational framework that combines MC and FDTD modeling, and allows random sampling of scattering directions from FDTD phase functions. We carry out simulations to assess the influence of incorporating realistic FDTD phase functions on modeling spectroscopic reflectance signals obtained from normal and precancerous epithelial tissues. Simulations employ various fiber optic probe designs to analyze the sensitivity of different probe geometries to FDTD-generated phase functions. Combined MC/FDTD modeling results indicate that the form of the phase function used is an important factor in determining the reflectance profile of tissues, and detected reflectance intensity can change up to approximately 30% when a realistic FDTD phase function is used instead of an approximating function. The results presented need to be taken into account when developing photon propagation models or implementing inverse algorithms to extract optical properties from measurements.     

Fine-tiling array CGH to improve diagnostics for α- and β-thalassemia rearrangements

Implementation of multiplex ligation-dependent probe amplification (MLPA) for thalassemia causing deletions has lead to the detection of new rearrangements. Knowledge of the exact breakpoint sequences should give more insight into the molecular mechanisms underlying these rearrangements, and would facilitate the design of gap-PCRs. We have designed a custom fine-tiling array with oligonucleotides covering the complete globin gene clusters. We hybridized 27 DNA samples containing newly identified deletions and nine positive controls. We designed specific primers to amplify relatively short fragments containing the breakpoint sequence and analyzed these by direct sequencing. Results from nine positive controls showed that array comparative genomic hybridization (aCGH) is suitable to detect small and large rearrangements. We were able to locate all breakpoints to a region of approximately 2 kb. We designed breakpoint primers for 22 cases and amplification was successful in 19 cases. For 12 of these, the exact locations of the breakpoints were determined. Seven of these deletions have not been reported before. aCGH is a valuable tool for high-resolution breakpoint characterization. The combination of MLPA and aCGH has lead to relatively cheap and easy to perform PCR assays, which might be of use for laboratories as an alternative for MLPA in populations where only a limited number of specific deletions occur with high frequency.     

Effect of Oxidative Stress on Membrane Proteins in Thalassemia and Iron Deficiency Anemia

Objective  

To evaluate the effect of oxidative stress on membrane proteins according to relationship between malondialdehyde (MDA) levels and membrane protein ratios in different two patient groups.     

Multimodality Image‐Guided Cryoablation for Inoperable Tumor‐Induced Osteomalacia

Tumor‐induced osteomalacia (TIO) is a debilitating paraneoplastic condition caused by small phosphaturic mesenchymal tumors (PMTs) that secrete large amounts of the phosphate‐regulating and vitamin D‐regulating hormone, FGF23. Tumor removal results in cure. However, because of high perioperative comorbidity, either from tumor location or host factors, surgery is sometimes not an option. Tumor destruction via cryoablation may be an effective option for inoperable PMTs. Three subjects with a confirmed diagnosis of TIO were studied. All three underwent cryoablation of suspected PMTs rather than surgery due to significant medical comorbidities or challenging anatomical location. Subject 3 had tumor embolization 24 hours prior to cryoablation because of the size and hypervascularity of the tumor. The success of the tumor cryoablation was defined by normalization of serum phosphate and FGF23. Cryoablation resulted in a rapid decrease in plasma intact FGF23 by 24 hours postprocedure in all three subjects (0, 2, and 9 pg/mL, respectively) with normalization of blood phosphate by postprocedure day 3. Three‐day renal tubular reabsorption of phosphate increased to 76%, 94%, and 95.2%, respectively; 1, 25(OH)₂ vitamin D increased to 84, 138, and 196 pg/ml, respectively. All three had dramatic clinical improvement in pain and weakness. Two subjects tolerated the procedure well with no complications; one had significant prolonged procedure‐related localized pain. Although surgery remains the treatment of choice, cryoablation may be an effective, less invasive, and safe treatment for patients with difficult to remove tumors or who are poor surgical candidates. © 2017 American Society for Bone and Mineral Research.