Mutational analysis of MYO1E in children with sporadic steroid-resistant nephrotic syndrome in Chinese Han ethnic group / 中华儿科杂志

<p><b>OBJECTIVE</b>Previous studies have demonstrated that two homozygous missense MYO1E mutations are associated with childhood autosomal recessive focal segmental glomerulosclerosis in steroid-resistant nephrotic syndrome (SRNS) families from Italy and Turkey. Non-disease-causing heterozygous MYO1E variants were also found in other SRNS patient cohorts. However, the role of MYO1E mutations in Chinese sporadic SRNS has not been established.</p><p><b>METHOD</b>Peripheral blood samples were collected for genetic analysis from 54 children with sporadic SRNS in Chinese Han ethnic group and a normal control group of 59 healthy adult volunteers. None of the patients carried mutations in NPHS2 or WT1. Genomic DNA was extracted from peripheral blood leukocytes. Twenty-eight exons and exon-intron boundaries of the MYO1E gene were amplified by polymerase chain reaction. Mutational analysis was performed by direct DNA sequencing and restriction endonuclease digestion.</p><p><b>RESULT</b>Fifty-one variants in the MYO1E gene were identified in 54 children with sporadic SRNS. Among them, 10 MYO1E mutations of IVS1-11T>C, IVS2-86T>A, 279T>C (D93D), IVS6-181G>A, 718C>T (L240F), 1678A>G (T560A), IVS16-35A>G, IVS18+48T>A, IVS19+38G>A and IVS25+13C>T were detected in 11 patients, whereas they were absent in the 59 normal Chinese controls. Forty-one variants in MYO1E were identified and all of them were published in single nucleotide polymorphism database from national center for biotechnology information. Furthermore, all the 10 MYO1E mutations were in heterozygous states.</p><p><b>CONCLUSION</b>MYO1E mutations are not a major cause of Chinese children with sporadic SRNS in the study.</p>

Mutational analysis of MYO1E in Chinese children with familial steroid-resistant nephrotic syndrome / 中国当代儿科杂志

<p><b>OBJECTIVE</b>Steroid-resistant nephrotic syndrome (SRNS) with MYO1E mutations has been identified as autosomal recessive focal segmental glomerulosclerosis (FSGS). To date, only two homozygous mutations in the MYO1E gene were reported in three families with FSGS. This study aimed to examine mutations in the MYO1E gene in children with familial SRNS in the Han Chinese ethnic group.</p><p><b>METHODS</b>Between 2005 and 2010, peripheral blood samples were collected from the probands, their siblings and parents of four families with autosomal recessive SRNS in the Han Chinese ethnic group. Four probands were studied from nine patients. The mutational analysis of MYO1E was performed by polymerase chain reaction and direct DNA sequencing. Fifty-nine healthy volunteers with normal urine analysis were included as controls.</p><p><b>RESULTS</b>Twenty-five MYO1E variants in the prohands from 4 families with SRNS were identified in this study. Among them, 24 variants were found in NCBI dbSNP. One heterozygous mutation IVS21-85G>A was found in the prohand from Family D, whereas it was absent in 59 normal Chinese controls. No splice site change caused by IVS21-85G>A was reported by analysis with NetGene2.</p><p><b>CONCLUSIONS</b>MYO1E mutations are not a major cause of Chinese familial SRNS in this study.</p>

Immunohistochemical fiber type profile in the human vocal muscle / Perfil inmunohistoquímico de los tipos de fibras en el músculo vocal humano

The vocal muscle is a striated muscle with important functions in the emission of laryngeal sound and physiology of the voice. Therefore the knowledge of its constitution is the basis for the prevention and management of voice disorders. We used 10 samples from the middle third of vocal muscles obtained from autopsies of 6 male and 4 female subjects aged between 36 and 71 years. The samples were analyzed with BA-F8 monoclonal antibody to slow type I fibers, and antimyosin HC monoclonal antibody and antimyosin fast clone MY-32 antibody for types IIA, IIB, IIX, and neonatal fibers. We determined the distribution of the muscle fiber types and morphometric characteristics, evaluating the differences by sex and age group. The human vocal muscle presented a heterogeneous formation with a predominance of type II fibers at 51.99 percent, while type I fibers reached 48.01 percent; this difference was significant (p <0.05). Comparing fiber subtypes IIA and IIX, there is a slight predominance of type IIX fibers, although this is not statistically significant (p>0.05). In conclusion, the human vocal muscle the fibers were predominantly type II fast.

El músculo vocal es un músculo estriado con importantes funciones en la emisión del sonido laringeo y fisiología de la voz. Por ello el conocimiento de su constitución sirve de base para la prevención y manejo de los trastornos vocales. Se realizó un estudio morfométrico e inmunohistoquímico de músculo vocal humano. Se utilizaron 10 muestras del tercio medio del músculo vocal obtenidas de necropsias, 6 de individuos de sexo masculino y 4 femenino, con edades de entre 36 y 71 años. Las muestras fueron analizadas con anticuerpos monoclonales antimyosin skeletal slow BA-F8 para fibras tipo I y antimyosin skeletal fast HC y MY-32 para fibras tipo IIA, IIB, IIX y neonatal. Se determinó la distribución de los distintos tipos de fibras musculares y sus características morfométricas, evaluándose las diferencias por sexo y grupo etáreo. El músculo vocal humano presentó una constitución heterogénea con predominio de fibras tipo II con un 51,99 por ciento, mientras que las tipo I alcanzaron el 48,01 por ciento, estas diferencias resultaron significativas (p<0,05). Al comparar los subtipos de fibras IIA y IIX, se observa un leve predominio de las fibras IIX, aunque no significativo estadísticamente (p>0,05). No se encontraron diferencias en cuanto a los diámetros mayor y menor de las fibras ni en la constitución del músculo por sexo o grupo etáreo. Se concluye que en el músculo vocal humano predominan las fibras musculares rápidas tipo II.