Voltage-dependent K+ currents in pear-shaped hair cells of the frog crista ampullaris were investigated in thin slice preparations using the whole-cell variant of the patch-clamp technique. Microscopy observation revealed that pear-shaped cells are located in intermediate and peripheral regions of the crista, whereas they are absent in the central region. Voltage-clamp recordings in cells from the peripheral regions revealed that the total outward K+ current could be separated pharmacologically into three distinct components: a A-type K+ current (IA); an inactivating calcium-activated K+ current (IK(Ca)) and a delayed rectifier K+ current (IK). IK and IK(Ca) exhibited similar magnitude and accounted for most of the membrane cell conductance. The same experimental protocol applied to cells from the intermediate regions showed the presence of a large and sustained IK(Ca) which represented 95% of the total outward current. In this region IA was absent. The present results demonstrated that pear-shaped hair cells located in two discrete regions of frog crista ampullaris exhibit a different complement of voltage-dependent conductances, suggesting that they can play a different role in processing the natural stimulus.
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http://dx.doi.org/10.1097/00001756-199607290-00031 | DOI Listing |
Eur J Med Genet
June 2024
Sheffield Institute for Translational Neuroscience, The University of Sheffield, Sheffield, UK. Electronic address:
Here we report the case of a young boy with developmental delay, thin sparse hair, early closure of the anterior fontanel, bilateral choanal atresia, brachyturicephaly; and dysmorphic features closely resembling those seen in trichorhinophalangeal syndrome (TRPS). These features include sparse hair, sparse lateral eyebrows, a bulbous pear shaped nose, a long philtrum, thin lips, small/hypoplastic nails, pes planovalgus; bilateral cone-shaped epiphyses at the proximal 5th phalanx, slender long bones, coxa valga, mild scoliosis, and delayed bone age. Given that TRPS had been excluded by a thorough genetic analysis, whole exome sequencing was performed and a heterozygous likely pathogenic variant was identified in the FBXO11 gene (NM_001190274.
View Article and Find Full Text PDFHorm Res Paediatr
February 2024
Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Introduction: Tricho-rhino-phalangeal syndrome (TRPS) is a rare genetic disorder characterized by craniofacial and skeletal abnormalities, which is caused by variants in the TRPS1 gene.
Methods: Clinical information and follow-up data were collected. Whole-exome sequencing (WES) was performed for variants and validated by Sanger sequencing.
Clin Genet
June 2023
Department of Radiology, Oregon Health & Science University, Portland, Oregon, USA.
Trichorhinophalangeal syndromes (TRPSs) are rare hereditary syndromes with autosomal dominant inheritance. Patients exhibit abnormalities including bulbous pear-shaped nose, broad columella, and long and flat philtrum, fine, sparse, brittle, slow-growing scalp hair, skeletal abnormalities, and short stature. Three families; age at subependymoma surgery, pathogenic TRPS1(NM_014112.
View Article and Find Full Text PDFTurk Arch Pediatr
January 2023
Department of Pediatric Genetics, İstanbul University-Cerrahpaşa, Cerrahpaşa Medical Faculty, Istanbul, Turkey.
Objective: Trichorhinophalangeal syndrome is a rare autosomal dominant disorder characterized by distinctive craniofacial and skeletal abnormalities. This study aimed to delineate the trichorhinophalangeal syndrome phenotype and to compare the clinical and molecular findings between trichorhinophalangeal syndrome types I and II.
Materials And Methods: A total of 22 trichorhinophalangeal syndrome patients aged 0.
Front Pediatr
November 2022
Department of Clinical Genetics, AmCare Genomics Lab, Guangzhou, China.
Tricho-rhino-phalangeal syndrome (TRPS) is a rare autosomal dominant malformation caused by mutations involving the 1 gene. Patients with TRPS exhibit distinctive craniofacial and skeletal abnormalities. This report presents three intra-familial cases with 1 gene mutations that showed the characteristic features of TRPS.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!