The Experts below are selected from a list of 645 Experts worldwide ranked by ideXlab platform

John F Otoole - One of the best experts on this subject based on the ideXlab platform.

  • mutational analysis of the nphp4 gene in 250 patients with nephronophthisis
    Human Mutation, 2005
    Co-Authors: Julia Hoefele, Boris Utsch, Richard Reinhardt, Massimo Attanasio, Ralf Sudbrak, Silvia Lehrack, Steffen Hennig, Anita Imm, Ulla Muerb, John F Otoole
    Abstract:

    Nephronophthisis (NPH), a recessive cystic kidney disease, is the most frequent genetic cause for end-stage renal disease in the first two decades of life. Mutations in three genes (NPHP1, 2, and 3) were identified as causative. Extrarenal manifestations are known, such as retinitis pigmentosa (Senior-Loken Syndrome, SLS) and ocular motor apraxia type Cogan. Recently, we identified a novel gene (NPHP4) as mutated in NPH. To date, a total of only 13 different NPHP4 mutations have been described. To determine the frequency of NPHP4 mutations, we performed mutational analysis by direct sequencing of all 30 NPHP4 exons in 250 different patients with isolated NPH, SLS, or Cogan Syndrome ascertained worldwide over 14 years. We identified 23 novel NPHP4 sequence variants in 26/250 different patients (10%). Interestingly, we detected homozygous or compound heterozygous mutations of NPHP4 in only 6/250 different patients (2.4%), but only one heterozygous NPHP4 sequence variant in 20/250 different patients (8%). In the six patients with two NPHP4 mutations, 5/8 mutations (63%) were likely loss-of-function mutations, whereas in the 20 patients with only one sequence variant, only 1/20 (5%) was a likely loss-of-function (i.e., truncating) mutation. We conclude that: i) two recessive mutations in NPHP4 are a rare cause of nephronophthisis; ii) single heterozygous NPHP4 sequence variants are three times more prevalent than two recessive mutations; iii) there is no genotype/phenotype correlation; iv) there must exist further genes causing nephronophthisis, since in 224/250 (90%) patients, no sequence variants in either of the four NPH genes were detected. © 2005 Wiley-Liss, Inc.

Julia Hoefele - One of the best experts on this subject based on the ideXlab platform.

  • mutational analysis of the nphp4 gene in 250 patients with nephronophthisis
    Human Mutation, 2005
    Co-Authors: Julia Hoefele, Boris Utsch, Richard Reinhardt, Massimo Attanasio, Ralf Sudbrak, Silvia Lehrack, Steffen Hennig, Anita Imm, Ulla Muerb, John F Otoole
    Abstract:

    Nephronophthisis (NPH), a recessive cystic kidney disease, is the most frequent genetic cause for end-stage renal disease in the first two decades of life. Mutations in three genes (NPHP1, 2, and 3) were identified as causative. Extrarenal manifestations are known, such as retinitis pigmentosa (Senior-Loken Syndrome, SLS) and ocular motor apraxia type Cogan. Recently, we identified a novel gene (NPHP4) as mutated in NPH. To date, a total of only 13 different NPHP4 mutations have been described. To determine the frequency of NPHP4 mutations, we performed mutational analysis by direct sequencing of all 30 NPHP4 exons in 250 different patients with isolated NPH, SLS, or Cogan Syndrome ascertained worldwide over 14 years. We identified 23 novel NPHP4 sequence variants in 26/250 different patients (10%). Interestingly, we detected homozygous or compound heterozygous mutations of NPHP4 in only 6/250 different patients (2.4%), but only one heterozygous NPHP4 sequence variant in 20/250 different patients (8%). In the six patients with two NPHP4 mutations, 5/8 mutations (63%) were likely loss-of-function mutations, whereas in the 20 patients with only one sequence variant, only 1/20 (5%) was a likely loss-of-function (i.e., truncating) mutation. We conclude that: i) two recessive mutations in NPHP4 are a rare cause of nephronophthisis; ii) single heterozygous NPHP4 sequence variants are three times more prevalent than two recessive mutations; iii) there is no genotype/phenotype correlation; iv) there must exist further genes causing nephronophthisis, since in 224/250 (90%) patients, no sequence variants in either of the four NPH genes were detected. © 2005 Wiley-Liss, Inc.

  • Mutational analysis of the NPHP4 gene in 250 patients with nephronophthisis." Hum Mutat 25(4
    2005
    Co-Authors: Julia Hoefele, Boris Utsch, Richard Reinhardt, Massimo Attanasio, Ralf Sudbrak, Silvia Lehrack, Steffen Hennig, Anita Imm, Ulla Muerb, John F. O’toole
    Abstract:

    Nephronophthisis (NPH), a recessive cystic kidney disease, is the most frequent genetic cause for end-stage renal disease in the first two decades of life. Mutations in three genes (NPHP1, 2, and 3) were identified as causative. Extrarenal manifestations are known, such as retinitis pigmentosa (Senior-Løken Syndrome, SLS) and ocular motor apraxia type Cogan. Recently, we identified a novel gene (NPHP4) as mutated in NPH. To date, a total of only 13 different NPHP4 mutations have been described. To determine the frequency of NPHP4 mutations, we performed mutational analysis by direct sequencing of all 30 NPHP4 exons in 250 different patients with isolated NPH, SLS, or Cogan Syndrome ascertained worldwide over 14 years. We identified 23 novel NPHP4 sequence variants in 26/250 different patients (10%). Interestingly, we detected homozygous or compound heterozygous mutations of NPHP4 in only 6/250 different patients (2.4%), but only one heterozygous NPHP4 sequence variant in 20/250 different patients (8%). In the six patients with two NPHP4 mutations, 5/

Howard W Francis - One of the best experts on this subject based on the ideXlab platform.

  • spectrum of immune mediated inner ear disease and cochlear implant results
    Laryngoscope, 2012
    Co-Authors: Mohammad U Malik, Vinciya Pandian, Hamid Masood, David A Diaz, Voss Varela, Alfredo Jose Davalosbalderas, Martha Parracardenas, Howard W Francis
    Abstract:

    Objectives/Hypothesis: To characterize the progression of hearing loss in patients with immune-mediated inner ear disease (IMIED), and to identify disease- and patient-specific factors associated with cochlear implant (CI) performance. Study Design: Retrospective cohort study. Methods: Subjects consisted of CI patients suspected to have lost their hearing due to IMIED. The primary dependent variable for functional decline was time to deafness, whereas for CI benefit it was post-CI speech perception scores. Independent variables included presence or absence of systemic autoimmune disease, age at CI, and insertion depth of the cochlear electrode. Results: A transient favorable response to immunosuppressive therapy was reported in 16 of 26 patients (66.67%). The time to deafness differed between an organ (ear)-specific immune-mediated group, a systemic immune-mediated group including Cogan Syndrome and relapsing polychondritis (subgroup A), and a systemic immune-mediated group associated with other autoimmune diseases (subgroup B; P = .001). Disease group (−15.52; P = .04), insertion depth of the CI electrode (40.71; P = .01), and the age at CI (−0.48, P = .05) were associated with speech perception results. Conclusions: Triaging IMIED cases based on presence and type of systemic autoimmune disease may aid in selecting a management strategy. Knowledge about the predictors of CI outcome will help clinicians select appropriate patients for CIs. In the setting of significant and irreversible hearing deficit, the restoration of hearing using a cochlear prosthesis may be appropriate earlier rather than later.

Richard Reinhardt - One of the best experts on this subject based on the ideXlab platform.

  • mutational analysis of the nphp4 gene in 250 patients with nephronophthisis
    Human Mutation, 2005
    Co-Authors: Julia Hoefele, Boris Utsch, Richard Reinhardt, Massimo Attanasio, Ralf Sudbrak, Silvia Lehrack, Steffen Hennig, Anita Imm, Ulla Muerb, John F Otoole
    Abstract:

    Nephronophthisis (NPH), a recessive cystic kidney disease, is the most frequent genetic cause for end-stage renal disease in the first two decades of life. Mutations in three genes (NPHP1, 2, and 3) were identified as causative. Extrarenal manifestations are known, such as retinitis pigmentosa (Senior-Loken Syndrome, SLS) and ocular motor apraxia type Cogan. Recently, we identified a novel gene (NPHP4) as mutated in NPH. To date, a total of only 13 different NPHP4 mutations have been described. To determine the frequency of NPHP4 mutations, we performed mutational analysis by direct sequencing of all 30 NPHP4 exons in 250 different patients with isolated NPH, SLS, or Cogan Syndrome ascertained worldwide over 14 years. We identified 23 novel NPHP4 sequence variants in 26/250 different patients (10%). Interestingly, we detected homozygous or compound heterozygous mutations of NPHP4 in only 6/250 different patients (2.4%), but only one heterozygous NPHP4 sequence variant in 20/250 different patients (8%). In the six patients with two NPHP4 mutations, 5/8 mutations (63%) were likely loss-of-function mutations, whereas in the 20 patients with only one sequence variant, only 1/20 (5%) was a likely loss-of-function (i.e., truncating) mutation. We conclude that: i) two recessive mutations in NPHP4 are a rare cause of nephronophthisis; ii) single heterozygous NPHP4 sequence variants are three times more prevalent than two recessive mutations; iii) there is no genotype/phenotype correlation; iv) there must exist further genes causing nephronophthisis, since in 224/250 (90%) patients, no sequence variants in either of the four NPH genes were detected. © 2005 Wiley-Liss, Inc.

  • Mutational analysis of the NPHP4 gene in 250 patients with nephronophthisis." Hum Mutat 25(4
    2005
    Co-Authors: Julia Hoefele, Boris Utsch, Richard Reinhardt, Massimo Attanasio, Ralf Sudbrak, Silvia Lehrack, Steffen Hennig, Anita Imm, Ulla Muerb, John F. O’toole
    Abstract:

    Nephronophthisis (NPH), a recessive cystic kidney disease, is the most frequent genetic cause for end-stage renal disease in the first two decades of life. Mutations in three genes (NPHP1, 2, and 3) were identified as causative. Extrarenal manifestations are known, such as retinitis pigmentosa (Senior-Løken Syndrome, SLS) and ocular motor apraxia type Cogan. Recently, we identified a novel gene (NPHP4) as mutated in NPH. To date, a total of only 13 different NPHP4 mutations have been described. To determine the frequency of NPHP4 mutations, we performed mutational analysis by direct sequencing of all 30 NPHP4 exons in 250 different patients with isolated NPH, SLS, or Cogan Syndrome ascertained worldwide over 14 years. We identified 23 novel NPHP4 sequence variants in 26/250 different patients (10%). Interestingly, we detected homozygous or compound heterozygous mutations of NPHP4 in only 6/250 different patients (2.4%), but only one heterozygous NPHP4 sequence variant in 20/250 different patients (8%). In the six patients with two NPHP4 mutations, 5/

Ralf Sudbrak - One of the best experts on this subject based on the ideXlab platform.

  • mutational analysis of the nphp4 gene in 250 patients with nephronophthisis
    Human Mutation, 2005
    Co-Authors: Julia Hoefele, Boris Utsch, Richard Reinhardt, Massimo Attanasio, Ralf Sudbrak, Silvia Lehrack, Steffen Hennig, Anita Imm, Ulla Muerb, John F Otoole
    Abstract:

    Nephronophthisis (NPH), a recessive cystic kidney disease, is the most frequent genetic cause for end-stage renal disease in the first two decades of life. Mutations in three genes (NPHP1, 2, and 3) were identified as causative. Extrarenal manifestations are known, such as retinitis pigmentosa (Senior-Loken Syndrome, SLS) and ocular motor apraxia type Cogan. Recently, we identified a novel gene (NPHP4) as mutated in NPH. To date, a total of only 13 different NPHP4 mutations have been described. To determine the frequency of NPHP4 mutations, we performed mutational analysis by direct sequencing of all 30 NPHP4 exons in 250 different patients with isolated NPH, SLS, or Cogan Syndrome ascertained worldwide over 14 years. We identified 23 novel NPHP4 sequence variants in 26/250 different patients (10%). Interestingly, we detected homozygous or compound heterozygous mutations of NPHP4 in only 6/250 different patients (2.4%), but only one heterozygous NPHP4 sequence variant in 20/250 different patients (8%). In the six patients with two NPHP4 mutations, 5/8 mutations (63%) were likely loss-of-function mutations, whereas in the 20 patients with only one sequence variant, only 1/20 (5%) was a likely loss-of-function (i.e., truncating) mutation. We conclude that: i) two recessive mutations in NPHP4 are a rare cause of nephronophthisis; ii) single heterozygous NPHP4 sequence variants are three times more prevalent than two recessive mutations; iii) there is no genotype/phenotype correlation; iv) there must exist further genes causing nephronophthisis, since in 224/250 (90%) patients, no sequence variants in either of the four NPH genes were detected. © 2005 Wiley-Liss, Inc.

  • Mutational analysis of the NPHP4 gene in 250 patients with nephronophthisis." Hum Mutat 25(4
    2005
    Co-Authors: Julia Hoefele, Boris Utsch, Richard Reinhardt, Massimo Attanasio, Ralf Sudbrak, Silvia Lehrack, Steffen Hennig, Anita Imm, Ulla Muerb, John F. O’toole
    Abstract:

    Nephronophthisis (NPH), a recessive cystic kidney disease, is the most frequent genetic cause for end-stage renal disease in the first two decades of life. Mutations in three genes (NPHP1, 2, and 3) were identified as causative. Extrarenal manifestations are known, such as retinitis pigmentosa (Senior-Løken Syndrome, SLS) and ocular motor apraxia type Cogan. Recently, we identified a novel gene (NPHP4) as mutated in NPH. To date, a total of only 13 different NPHP4 mutations have been described. To determine the frequency of NPHP4 mutations, we performed mutational analysis by direct sequencing of all 30 NPHP4 exons in 250 different patients with isolated NPH, SLS, or Cogan Syndrome ascertained worldwide over 14 years. We identified 23 novel NPHP4 sequence variants in 26/250 different patients (10%). Interestingly, we detected homozygous or compound heterozygous mutations of NPHP4 in only 6/250 different patients (2.4%), but only one heterozygous NPHP4 sequence variant in 20/250 different patients (8%). In the six patients with two NPHP4 mutations, 5/