A Molecular Genetic Study of X-Linked Nephrogenic Diabetes lnspidus

X-linked nephrogenic diabetes insipidus (NOI) is a rare disease characterized by absent vasopressin V2 receptor responses. Recently, the vasopressin V2 receptor gene (AVPR2 gene) was cloned, and several mutations have been reported in association with NO!. We analyzed the AVPR2 gene in a family with X-linked NO!. Genomic DNA was isolated from peripheral blood samples from 11 members of the family. Four overlapping segments covering the entire coding sequence of the AVPR2 gene were amplified by polymerase chain reaction (PCR) with the genomic DNA And DNA sequencing was done after subcloning of the PCR products into a plasmid vector. We found a mutation in the AVPR2 gene, common in 4 symptomatic male patients in the family. It was a novel missense point mutation at the codon 219 CTG to CCG resulting a transition of leucine-219, located in the 5th transmembrane domain of the receptor molecule, to proline. The T to C transition generated a new recognition site for a restriction enzyme Sma I. And 3 heterozygous female carriers of the mutant gene were detected by the pattern of Sma I digestion of PCR products including the mutation site. These results provided a strong evidence for that the mutation was the cause of NOI in this family

Long-term outcomes for Asian patients with X-linked hypophosphataemia : rationale and design of the SUNFLOWER longitudinal, observational cohort study

Introduction X-linked hypophosphataemic rickets/osteomalacia (XLH) is a chronic, debilitating genetic disease characterised by skeletal abnormalities and growth disorder. The burden of XLH begins in childhood and continues throughout life. Conventional medical therapy with phosphate, active vitamin D and surgery do not address the underlying pathophysiology of the disease. While treatment during childhood may improve bone deformity and growth retardation, a large proportion of adult patients still fail to reach normal stature. Furthermore, adult patients with XLH report comorbidities associated with unresolved childhood disease, as well as newly developed disease-related complications and significantly impaired quality of life (QOL). Despite the multiple negative aspects of XLH, Asian consensus statements for diagnosis and management are lacking. Methods and analysis The Study of longitUdinal observatioN For patients with X-Linked hypOphosphataemic rickets/osteomalacia in collaboration With Asian partnERs study is a longitudinal observational cohort study of patients with XLH, designed to determine the medical characteristics and burdens (physical, emotional and financial) of this progressive disease and to evaluate the impact of treatment (including the use of burosumab) on clinical outcomes. The study was initiated in April 2018, and registration will remain open until 30 April 2022. The sample size planned for analyses is 160 patients, consisting of 100 patients in Japan and 60 patients in Korea. Up to 5 years of observation are planned per patient, from enrolment through to April 2023. Prospective and retrospective data will be collected to evaluate variables, including height/growth, rickets severity score, QOL, motor function and biomarkers for phosphate metabolism and bone turnover. Ethics and dissemination Ethics approval was obtained from the Ethics Committee of Osaka University, the Ethics Committee of Kyowa Kirin Co and by the Ethics Committee of each participating medical institution. Two interim analyses and associated publications are planned using retrospective and enrolment data at year 1 and results at year 3

Renal transplantation in a patient with Bartter syndrome and glomerulosclerosis

Bartter syndrome (BS) is a clinically and genetically heterogeneous inherited renal tube disorder characterized by renal salt wasting, hypokalemic metabolic alkalosis and normotensive hyperreninemic hyperaldosteronism. There have been several case reports of BS complicated by focal segmental glomerulosclerosis (FSGS). Here, we have reported the case of a BS patient who developed FSGS and subsequent end-stage renal disease (ESRD) and provided a brief literature review. The patient presented with classic BS at 3 months of age and developed proteinuria at 7 years. Renal biopsy performed at 11 years of age revealed a FSGS perihilar variant. Hemodialysis was initiated at 11 years of age, and kidney transplantation was performed at 16 years of age. The post-transplantation course has been uneventful for more than 3 years with complete disappearance of BS without the recurrence of FSGS. Genetic study revealed a homozygous p.Trp(TGG)610Stop(TGA) mutation in the CLCNKB gene. In summary, BS may be complicated by secondary FSGS due to the adaptive response to chronic salt-losing nephropathy, and FSGS may progress to ESRD in some patients. Renal transplantation in patients with BS and ESRD results in complete remission of BS

Bilateral iliac and popliteal arterial thrombosis in a child with focal segmental glomerulosclerosis

Thromboembolic complications (TECs) are clinically important sequelae of nephrotic syndrome (NS). The incidence of TECs in children is approximately 2%–5%. The veins are the most commonly affected sites, particularly the deep veins in the legs, the inferior vena cava, the superior vena cava, and the renal veins. Arterial thrombosis, which is less common, typically occurs in the cerebral, pulmonary, and femoral arteries, and is associated with the use of steroids and diuretics. Popliteal artery thrombosis in children has been described in cases of traumatic dissection, osteochondroma, Mycoplasma pneumoniae infection, and fibromuscular dysplasia. We report of a 33-month-old girl with bilateral iliac and popliteal arterial thrombosis associated with steroid-resistant NS due to focal segmental glomerulosclerosis. Her treatment involved thrombectomy and intravenous heparinization, followed by oral warfarin for 8 months. Herein, we report a rare case of spontaneous iliac and popliteal arterial thrombosis in a young child with NS

A single nucleotide polymorphism in CAPN1 associated with marbling score in Korean cattle

<p>Abstract</p> <p>Background</p> <p>Marbling score (MS) is the major quantitative trait that affects carcass quality in beef cattle. In this study, we examined the association between genetic polymorphisms of the micromolar calcium-activated neutral protease gene (micro-calpain, <it>CAPN1</it>) and carcass traits in Korean cattle (also known as Hanwoo).</p> <p>Results</p> <p>By direct DNA sequencing in 24 unrelated Korean cattle, we identified 39 sequence variants within exons and their flanking regions in <it>CAPN1</it>. Among them, 12 common polymorphic sites were selected for genotyping in the beef cattle (<it>n </it>= 421). Statistical analysis revealed that a polymorphism in the 3'UTR (<it>c.2151*479C>T</it>) showed significant association with MS (<it>P</it>^{<it>cor</it>.}= 0.02).</p> <p>Conclusion</p> <p>Our findings suggest that polymorphisms in <it>CAPN1 </it>might be one of the important genetic factors involved in carcass quality in beef cattle, although it could be false positive association.</p

The Pathogenetic Role of Reactive Oxygen Species in Aminonucleoside Nephrosis

We studied the pathogenetic role of reactive oxygen species (ROS) in rats with puromycin aminonucleoside nephrosis (PAN). Heavy albuminuria with markedly decreased density of the anionic sites (AS) on glomerular basement membrane (GBM) (2. 6 ± O. 98 compared to 20. 0 ± 1. 61 AS/l,OOOnm GBM in control) developed 7 days after PA injection. The malondialdehyde (MDA) levels in kidney homogenates increased gradually (1. 16 ± O. 18 at day -1 to 1. 97 ± O. 23/g protein at day 5). While catalase or dimethyl sulfoxide, administered with PA, did not affect the course of PAN. superoxide dismutase and allopurinol reduced proteinuria and decreased loss of the AS (11. 7 ± 2. 80 and 13, 7 ± 1. 27 AS/l.000nm GBM, reo spectively) at day 7. These findings suggest that proteinuria in PAN results from the loss of GBM AS. in which ROS generated by xanthine oxidase system plays an import. ant role

Proteinuria in a Boy with Infectious Mononucleosis, C1q Nephropathy, and Dent's Disease

C1q nephropathy is a proliferative glomerulopathy with extensive mesangial deposition of C1q. A three-year old boy presented with a nephrotic-range proteinuria during an acute phase of Epstein-Barr virus (EBV) infection, and he had a family history of Dent's disease. The renal biopsy findings were compatible with C1q nephropathy. However, EBV in situ hybridization was negative. The CLCN5 gene analysis revealed an R637X hemizygous mutation, which was the same as that detected in his maternal cousin, the proband of the family. The causal relationship between EBV infection and C1q nephropathy remains to be determined. Moreover, the effects of underlying Dent's disease in the process of C1q nephropathy has to be considered

Two Novel Mutations in the Aquaporin 2 Gene in a Girl with Congenital Nephrogenic Diabetes Insipidus

Congenital nephrogenic diabetes insipidus (CNDI) is a rare inherited disorder characterized by insensitivity of the kidney to the antidiuretic effect of vasopressin. There are three inheritance patterns of CNDI: the X-linked recessive form associated with vasopressin V2 receptor gene mutations, and the autosomal recessive and dominant forms associated with aquaporin-2 gene (AQP2) mutations. The evaluation for polyuria and polydipsia in a one-month-old Korean girl revealed no response to vasopressin and confirmed the diagnosis of CNDI. Because the child was female without family history of CNDI, her disease was thought to be an autosomal recessive form. We analyzed the AQP2 gene and detected a compound heterozygous missense point mutation: 70Ala (GCC) to Asp (GAC) in exon 1 inherited from her father and 187Arg (CGC) to His (CAC) in exon 3 inherited from her mother. The first mutation is located within the first NPA motif of the AQP2 molecule and the second one right after the second NPA motif. This is the first report to characterize AQP2 mutations in Korean patients with autosomal recessive CNDI, and expands the spectrum of AQP2 mutations by reporting two novel mutation, 70Ala (GCC) to Asp (GAC) and 187Arg (CGC) to His (CAC)