Papillorenal Syndrome after Beta-Interferon Treatment in Pregnancy

Papillo-Renal Syndrome (PRS, or Renal-Coloboma Syndrome) is an autosomal dominant disorder, characterized by colobomatous eye defects, abnormal vascular pattern of the optic disk, renal hypoplasia, vesicoureteral reflux, high-frequency hearing loss, and sometimes central nervous system (CNS) abnormalities. The syndrome is associated with mutations in the PAX2 gene. This 11-year-old girl's mother was treated with beta-interferon (IFNβ-1a) for multiple sclerosis (MS) during the pregnancy. The child failed to thrive in infancy and early childhood. The multicystic renal dystrophy, hypoplastic right kidney, and vesico-ureteral reflux (II–III grade) were diagnosed by ultrasound and radionucleotide renal scan. Subsequently, a morning glory anomaly and coloboma of the optic disc was discovered. Renal failure progressively followed. MRI of the head revealed a cyst of the right optic nerve. Genetic analysis revealed a mutation of the PAX2 gene (619 insG). The multicystic renal dystrophy and a cyst of the optic nerve in association with PRS syndrome have only rarely been described. The fact that this PRS patient stemmed from a pregnancy under beta-interferon treatment raises the question whether IFNβ-1a treatment during pregnancy has influenced the manifestation or the severity of the PAX2 mutant phenotype in this child.     

Mild Recessive Mutations in Six Fraser Syndrome–Related Genes Cause Isolated Congenital Anomalies of the Kidney and Urinary Tract

Congenital anomalies of the kidney and urinary tract (CAKUT) account for approximately 40% of children with ESRD in the United States. Hitherto, mutations in 23 genes have been described as causing autosomal dominant isolated CAKUT in humans. However, >90% of cases of isolated CAKUT still remain without a molecular diagnosis. Here, we hypothesized that genes mutated in recessive mouse models with the specific CAKUT phenotype of unilateral renal agenesis may also be mutated in humans with isolated CAKUT. We applied next-generation sequencing technology for targeted exon sequencing of 12 recessive murine candidate genes in 574 individuals with isolated CAKUT from 590 families. In 15 of 590 families, we identified recessive mutations in the genes FRAS1, FREM2, GRIP1, FREM1, ITGA8, and GREM1, all of which function in the interaction of the ureteric bud and the metanephric mesenchyme. We show that isolated CAKUT may be caused partially by mutations in recessive genes. Our results also indicate that biallelic missense mutations in the Fraser/MOTA/BNAR spectrum genes cause isolated CAKUT, whereas truncating mutations are found in the multiorgan form of Fraser syndrome. The newly identified recessive biallelic mutations in these six genes represent the molecular cause of isolated CAKUT in 2.5% of the 590 affected families in this study.     

Characterization of a cell line derived from a human oligodendroglioma

A novel clonal cell line derived from a human glioma (HOG) was found to express some oligodendrocyte-specific proteins including a 15-kDa form of myelin basic protein (MBP) and high 2′,3′-cyclic nucleotide 3′-phosphodiesterase (CNPase) activity. Expression of the myelin lipids galactosylceramide and sulfogalactosylceramide (sulfatide) was low. HOG cells did not express the characteristic astrocyte markers glial fibrillary acidic protein (GFAP) or significant glutamine synthetase (GS) activity. After initial plating, HOG cells were flat and epitheloid and thus showed a limited oligodendrocyte-like morphology. However, after cells became more confluent, some cells were phase-bright and elaborated short processes. Receptor types expressed by HOG cells included A₂-adenosine, prostaglandin E₁ (PGE₁), andβ ₂-adrenergic receptors (β-ARs) linked to stimulation of adenylate cyclase, and muscarinic cholinergic and H₁-histamine coupled to phosphatidyinositol turnover (Post and Dawson, 1991). HOG cells should therefore provide a useful model for studying the extracellular regulation and phosphorylation of oligodendrocyte-specific proteins.     

Simultaneous LC determination of tiazofurin,its acetyl and benzoyl esters and their active metabolite thiazole-4-carboxamide adenine dinucleotide in biological samples

A rapid and sensitive HPLC-RP method for simultaneous determination of tiazofurin, its 5'-O acetyl and benzoyl esters and their active metabolite thiazole-4-carboxamide adenine dinucleotide was developed and validated. The method allowed determination and quantification of nanomolar quantities of these substances in cell extracts of treated cells, and was also used in kinetic studies of cellular uptake of tiazofurin and its esters from the cultivation medium. Separation of the analyzed substances from unidentified peaks from both biological materials was achieved by gradient elution, thus reducing the possibility of interference. The mobile phase consisted of a 0.1 M sodium-hydrogen phosphate, pH 5.1 and methanol. Run time was 22 min, with 5 min equilibration time.     

Clinical and laboratory features of Macedonian children with OCRL mutations

OCRL mutations, which are a hallmark of Lowe syndrome, have recently been found in patients with isolated renal phenotype (Dent-2 disease). In this report, we describe clinical and laboratory features in five Macedonian children with mutations in the OCRL gene. Children with a clinical diagnosis of Lowe syndrome or Dent disease underwent complete neurological and ophthalmological examination, imaging of the kidney and urinary tract, assessment of renal tubular function, and mutation analysis of the OCRL gene. Two children (18 months and 11 years, respectively) were diagnosed with Lowe syndrome on the basis of congenital cataracts, severe psychomotor retardation, and renal dysfunction. Both children had low molecular weight proteinuria (LMWP) and hypercalciuria, but not Fanconi syndrome. The older one had bilateral nephrolithiasis due to associated hypocitraturia and mild hyperoxaluria. Three children with asymptomatic proteinuria were diagnosed with Dent-2 disease; none had cataracts or neurological deficit. One child showed mild mental retardation. All had LMWP, hypercalciuria, and elevated enzymes (creatine phosphokinase, lactic dehydrogenase). All three children had an abnormal Tc-99m DMSA scan revealing poor visualization of the kidneys with a high radionuclide content in the bladder; none had nephrolithiasis or nephrocalcinosis. In conclusion, children with OCRL mutations may present with very mild phenotype (asymptomatic proteinuria with/without mild mental retardation) or severe classic oculocerebrorenal syndrome of Lowe. Elevated enzymes and abnormal results on the Tc-99m DMSA scan may be useful indicators for Dent-2 disease.     

Managing the care of patients receiving antiresorptive therapy for prevention and treatment of osteoporosis: executive summary of recommendations from the American Dental Association Council on Scientific Affairs

BackgroundThis narrative review of osteonecrosis of the jaw in patients with low bone mass receiving treatment with antiresorptive agents is based on an appraisal of the literature by an advisory committee of the American Dental Association Council on Scientific Affairs. It updates the committee’s 2008 advisory statement.MethodsThe authors searched MEDLINE for literature published between May 2008 (the end date of the last search) and February 2011.ResultsThis report contains recommendations based on the findings of the literature search and on expert opinion that relate to general dentistry; periodontal disease management; implant placement and maintenance; oral and maxillofacial surgery; endodontics; restorative dentistry and prosthodontics; orthodontics; and C-terminal telopeptide testing and drug holidays.ConclusionsThe highest reliable estimate of antiresorptive agent–induced osteonecrosis of the jaw (ARONJ) prevalence is approximately 0.10 percent. Osteoporosis is responsible for considerable morbidity and mortality. Therefore, the benefit provided by antiresorptive therapy outweighs the low risk of developing osteonecrosis of the jaw.Clinical ImplicationsAn oral health program consisting of sound hygiene practices and regular dental care may be the optimal approach for lowering ARONJ risk. No validated diagnostic technique exists to determine which patients are at increased risk of developing ARONJ. Discontinuing bisphosphonate therapy may not lower the risk but may have a negative effect on low-bone-mass–treatment outcomes.     

Voxel-based morphometric MRI post-processing in MRI-negative focal cortical dysplasia followed by simultaneously recorded MEG and stereo-EEG

We aim to report on the usefulness of a voxel-based morphometric MRI post-processing technique in detecting subtle epileptogenic structural lesions. The MRI post-processing technique was implemented in a morphometric analysis program (MAP), in a 30-year-old male with pharmacoresistant focal epilepsy and negative MRI. MAP gray-white matter junction file facilitated the identification of a suspicious structural lesion in the right frontal opercular area. The electrophysiological data by simultaneously recorded stereo-EEG and MEG confirmed the epileptogenicity of the underlying subtle structural abnormality. The patient underwent a limited right frontal opercular resection, which completely included the area detected by MAP. Surgical pathology revealed focal cortical dysplasia (FCD) type IIb. Postoperatively the patient has been seizure-free for 2 years. This study demonstrates that MAP has promise in increasing the diagnostic yield of MRI reading in challenging patients with "non-lesional" MRIs. The clinical relevance and epileptogenicity of MAP abnormalities in patients with epilepsy have not been investigated systematically; therefore it is important to confirm their pertinence by performing electrophysiological recordings. When confirmed to be epileptogenic, such MAP abnormalities may reflect an underlying subtle cortical dysplasia whose complete resection can lead to seizure-free outcome.     

The role of insulin-like growth factors signaling in merlin-deficient human schwannomas

Loss of the tumor suppressor merlin causes development of the tumors of the nervous system, such as schwannomas, meningiomas, and ependymomas occurring spontaneously or as part of a hereditary disease Neurofibromatosis Type 2 (NF2). Current therapies, (radio) surgery, are not always effective. Therefore, there is a need for drug treatments for these tumors. Schwannomas are the most frequent of merlin‐deficient tumors and are hallmark for NF2. Using our in vitro human schwannoma model, we demonstrated that merlin‐deficiency leads to increased proliferation, cell–matrix adhesion, and survival. Increased proliferation due to strong activation of extracellular‐signal‐regulated kinase 1/2 (ERK1/2) is caused by overexpression/activation of platelet‐derived growth factor receptor‐β (PDGFR‐β) and ErbB2/3 which we successfully blocked with AZD6244, sorafenib, or lapatinib. Schwannoma basal proliferation is, however, only partly dependent on PDGFR‐β and is completely independent of ErbB2/3. Moreover, the mechanisms underlying pathological cell–matrix adhesion and survival of schwannoma cells are still not fully understood. Here, we demonstrate that insulin‐like growth factor‐I receptor (IGF‐IR) is strongly overexpressed and activated in human primary schwannoma cells. IGF‐I and ‐II are overexpressed and released from schwannoma cells. We show that ERK1/2 is relevant for IGF‐I‐mediated increase in proliferation and cell–matrix adhesion, c‐Jun N‐terminal kinases for increased proliferation and AKT for survival. We demonstrate new mechanisms involved in increased basal proliferation, cell–matrix adhesion, and survival of schwannoma cells. We identified therapeutic targets IGF‐IR and downstream PI3K for treatment of schwannoma and other merlin‐deficient tumors and show usefulness of small molecule inhibitors in our model. PI3K is relevant for both IGF‐IR and previously described PDGFR‐β signaling in schwannoma. © 2012 Wiley Periodicals, Inc.