ABSTRACT
In mammals, the piezoelectric protein, Prestin, endows the outer hair cells (OHCs) with electromotility (eM), which confers the capacity to change cellular length in response to alterations in membrane potential. Together with basilar membrane resonance and possible stereociliary motility, Prestin-based OHC eM lays the foundation for enhancing cochlear sensitivity and frequency selectivity. However, it remains debatable whether Prestin contributes to ultrahigh-frequency hearing due to the intrinsic nature of the cell's low-pass features. The low-pass property of mouse OHC eM is based on the finding that eM magnitude dissipates within the frequency bandwidth of human speech. In this study, we examined the role of Prestin in sensing broad-range frequencies (4-80 kHz) in mice that use ultrasonic hearing and vocalization (to >100 kHz) for social communication. The audiometric measurements in mice showed that ablation of Prestin did not abolish hearing at frequencies >40 kHz. Acoustic associative behavior tests confirmed that Prestin-knockout mice can learn ultrahigh-frequency sound-coupled tasks, similar to control mice. Ex vivo cochlear Ca2+ imaging experiments demonstrated that without Prestin, the OHCs still exhibit ultrahigh-frequency transduction, which in contrast, can be abolished by a universal cation channel blocker, Gadolinium. In vivo salicylate treatment disrupts hearing at frequencies <40 kHz but not ultrahigh-frequency hearing. By pharmacogenetic manipulation, we showed that specific ablation of the OHCs largely abolished hearing at frequencies >40 kHz. These findings demonstrate that cochlear OHCs are the target cells that support ultrahigh-frequency transduction, which does not require Prestin.
Subject(s)
Animals , Humans , Mice , Cochlea/metabolism , Hair Cells, Auditory, Outer/metabolism , Hearing , Mammals/metabolism , Mice, Knockout , Molecular Motor Proteins/metabolismABSTRACT
OBJECTIVE@#To identify the mutation type of non-muscle myosin heavy chain 9 (MYH9) gene and investigate the clinical features of a pedigree affected with MYH9 gene-related disease.@*METHODS@#Peripheral blood samples of the proband and his family members were collected. Routine blood tests were performed, which included platelet counting and Wright's staining to observe the granulocyte inclusions and giant platelets. PCR was used to amplify exons 2, 17, 27, 31, 39 and 41 of the MYH9 gene, and the mutation site was determined by Sanger sequencing.@*RESULTS@#All patients from the pedigree presented a typical triad of thrombocytopenia, giant platelets, and inclusion bodies in leukocytes. In addition, two patients had nephritis and cataract. All affected members carried a heterozygous missense mutation of c.5521G>A (p.glu1841Lys) in exon 39 of the MYH9 gene. The same mutation was not found among healthy members of the pedigree and the controls.@*CONCLUSION@#The c.5521G>A (p.Glu1841Lys) mutation in the MYH9 gene probably underlies the MYH9-related disease in this pedigree.
Subject(s)
Female , Humans , Male , Genetic Testing , Molecular Motor Proteins , Genetics , Mutation , Myosin Heavy Chains , Genetics , Pedigree , ThrombocytopeniaABSTRACT
<p><b>OBJECTIVE</b>To study genetic mutations and clinical features of a pedigree affected with MYH9-related disorders from Guangxi.</p><p><b>METHODS</b>Blood platelets were counted with a hemocytometer. Blood smear was carried out to detect the inclusion body in peripheral blood neutrophils. DNA and mRNA samples were extracted from blood samples from the members of the pedigree. Fragments of the MYH9 gene were amplified with PCR and directly sequenced.</p><p><b>RESULTS</b>The affected individuals presented with a triad of giant platelets, decreased platelet count and inclusion bodies in the neutrophils with variable expressivity. A heterozygous deletional mutation (c.5803delG) in exon 41 of the MYH9 gene was found in all of the 8 affected individuals, which led to a frame-shift and change of 26 amino acids at the C-end of the tail domain of nonmuscle myosin heavy chain IIA (NMMHC-IIA) (p.Ala1935Profs*12). The same mutation was not found among healthy members of the pedigree.</p><p><b>CONCLUSION</b>The c.5803delG mutation probably underlies the MYH9-related disorders in this pedigree. The mutation has altered the C-end of the tail domain of the NMMHC-IIA protein, resulting in mild clinical symptoms in the affected individuals.</p>
Subject(s)
Adult , Female , Humans , Male , Base Sequence , China , Molecular Motor Proteins , Genetics , Molecular Sequence Data , Myosin Heavy Chains , Genetics , Pedigree , Sequence Deletion , Thrombocytopenia , Diagnosis , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To analyze the clinical manifestations and mutation of MYH9 gene in a large Chinese family affected with MYH9-related thrombocytopenia.</p><p><b>METHODS</b>After informed consent was obtained; clinical examination and history investigation was performed on 29 members of the family. DNA was extracted using a standard method, then exons 1 to 40 and their corresponding exon-intron junctions of the MYH9 gene were amplified with PCR and subjected to Sanger sequencing. The results were compared to reference sequence from the University of California, Santa Cruz (UCSC) to screen the mutation. PCR and Sanger sequencing was performed on genome DNA of all family members to confirm the identified mutation.</p><p><b>RESULTS</b>The clinical manifestations of family members were prominently heterogeneous. Four affected members showed hearing loss or deafness, two affected members showed nephritis or kidney failure, and other affected members was only characterized by mild bleeding or with no obvious symptoms. A heterozygous missense mutation c.4270G>A (p.Aspl841Asn) in exon 30 of the MYH9 gene was identified in all affected members from this family, which also co-segregated with the phenotype.</p><p><b>CONCLUSION</b>A missense mutation c.4270G>A (p.Aspl841Asn) within the exon 30 of the MYH9 gene was identified to be associated with MYH9-related thrombocytopenia in a Chinese family.</p>
Subject(s)
Female , Humans , Male , Amino Acid Sequence , Asian People , Genetics , China , DNA Mutational Analysis , Exons , Genetics , Family Health , Genetic Predisposition to Disease , Ethnology , Genetics , Heterozygote , Molecular Motor Proteins , Genetics , Mutation, Missense , Myosin Heavy Chains , Genetics , Pedigree , Sequence Homology, Amino Acid , Thrombocytopenia , Ethnology , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To construct a MYH9 gene knockout model in MGC803 cell line using transcription activator-like effector nuclease (TALEN) and observe its effect on cell cycle and apoptosis.</p><p><b>METHODS</b>According to FastTALE(TM) TALEN Kit, we designed TALEN pairs and constructed the plasmids targeting to MYH9 gene. After detecting their activity in MGC803 cells by plasmid transfection, DNA sequencing, RT-PCR and western blot, we selected the monoclonal cells and studied the changes in the cell cycle and apoptosis.</p><p><b>RESULTS</b>MYH9 gene could not be knocked out but knocked down in selected MGC803 monoclonal cells, which caused cell cycle arrested at G2/M phase (P<0.05) and a significant increase in the cell number with early apoptosis (P<0.01).</p><p><b>CONCLUSION</b>We successfully generated a MYH9 knockdown model in MGC803 cell lines by TALEN, which could be in favor of MYH9 function study in gastric cancer.</p>
Subject(s)
Humans , Apoptosis , Cell Cycle , Cell Line, Tumor , Cell Proliferation , Gene Knockdown Techniques , Molecular Motor Proteins , Genetics , Myosin Heavy Chains , Genetics , Plasmids , Stomach Neoplasms , TransfectionABSTRACT
BACKGROUND AND OBJECTIVES: In this study, the aim was to compare postoperative analgesia effects of the administration of ultrasound-guided interscalene brachial plexus block and intra-articular bupivacaine carried out with bupivacaine. METHODS: In the first group of patients 20 mL 0.25% bupivacaine and ultrasound-guided interscalene brachial plexus block (ISPB) were applied, while 20 mL 0.25% bupivacaine was given via intra-articular (IA) administration to the second group patients after surgery. Patients in the third group were considered the control group and no block was performed. Patient-controlled analgesia (PCA) with morphine was used in all three groups for postoperative analgesia. RESULTS: In the ISPB group, morphine consumption in the periods between 0-4, 6-12 and 12-24 postoperative hours and total consumption within 24 h was lower than in the other two groups. Morphine consumption in the IA group was lower than in the control group in the period from 0 to 6 h and the same was true for total morphine consumption in 24 h. Postoperative VASr scores in the ISPB group were lower than both of the other groups in the first 2 h and lower than the control group in the 4th and 6th hours (p < 0.05). In the IA group, VASr and VASm scores in the 2nd, 4th and 6th hours were lower than in the control group (p < 0.05). CONCLUSION: Interscalene brachial plexus block was found to be more effective than intra-articular local anesthetic injection for postoperative analgesia. .
JUSTIFICATIVA E OBJETIVOS: Comparar os efeitos na analgesia no pós-operatório da administração de bloqueio do plexo braquial por via interescalênica guiado por ultrassom e bupivacaína intra-articular, feito com bupivacaína. MÉTODOS: No primeiro grupo de pacientes, 20 mL de bupivacaína a 0,25% e bloqueio do plexo braquial por via interescalênica guiado por ultrassom (BPBI) foram administrados, enquanto 20 mL de bupivacaína a 0,25% foram administrados por via intra-articular (IA) ao segundo grupo de pacientes após a cirurgia. Os pacientes do terceiro grupo foram considerados grupo controle e nenhum bloqueio foi feito. Analgesia controlada pelo paciente (ACP) com morfina foi usada nos três grupos para analgesia pós-operatória. RESULTADOS: No grupo BPBI, o consumo de morfina nos períodos entre 0-4, 6-12 e 12-24 horas após a cirurgia e o consumo total em 24 horas foram mais baixos do que nos outros dois grupos. O consumo de morfina no grupo IA foi menor do que no grupo controle no período de 0-6 horas, como também foi menor o consumo total de morfina em 24 horas. Os escores EVAr no pós-operatório do grupo BPBI foram menores do que os escores dos dois outros grupos nas primeiras duas horas e menores do que os do grupo controle nos períodos de 4 e 6 horas (p < 0,05). No grupo IA, os escores EVAr e EVAm nos períodos de 2, 4 e 6 horas foram menores do que no grupo controle (p < 0,05). CONCLUSÃO: O bloqueio do plexo braquial por via interescalênica mostrou ser mais eficaz do que a injeção intra-articular de anestésico local para analgesia pós-operatória. .
JUSTIFICACIÓN Y OBJETIVOS: En este estudio, nuestro objetivo fue comparar en el período postoperatorio los efectos analgésicos de la administración de la bupivacaína en el bloqueo del plexo braquial por vía interescalénica guiado por ecografía y bupivacaína intraarticular. MÉTODOS: En el primer grupo de pacientes se administraron 20 mL de bupivacaína al 0,25% y se llevó a cabo el bloqueo del plexo braquial por vía interescalénica (BPBI) guiado por ecografía, mientras que al segundo grupo de pacientes se le administraron 20 mL de bupivacaína al 0,25% por vía intraarticular (IA) tras la cirugía. Los pacientes del tercer grupo fueron considerados como grupo control y en ellos no se realizó ningún bloqueo. La analgesia controlada por el paciente con morfina se usó en los 3 grupos para la analgesia postoperatoria. RESULTADOS: En el grupo BPBI, el consumo de morfina en los períodos entre 0-4, 6-12 y 12-24 h del postoperatorio y el consumo total en 24 h fueron más bajos que en los otros 2 grupos. El consumo de morfina en el grupo IA fue menor que en el grupo control en el período de 0-6 h, como también fue menor el consumo total de morfina en 24 h. Las puntuaciones EVAr en el postoperatorio del grupo BPBI fueron menores que las de los otros 2 grupos en las primeras 2 h y menores que los del grupo control en los períodos de 4 y 6 h (p < 0,05). En el grupo IA, las puntuaciones EVAr y EVAm en los períodos de 2, 4 y 6 h fueron menores que en el grupo control (p < 0,05). CONCLUSIÓN: El BPBI mostró ser más eficaz que la inyección intraarticular de anestésico local para analgesia postoperatoria. .
Subject(s)
Dyneins/metabolism , Kinesins/metabolism , Microtubule-Associated Proteins/metabolism , Microtubules/metabolism , Molecular Motor Proteins/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/metabolism , Dyneins/chemistry , Dyneins/isolation & purification , Models, Biological , Multiprotein Complexes/metabolism , Protein Structure, Tertiary , Protein TransportABSTRACT
<p><b>OBJECTIVE</b>To analyze clinical features and mutation in MYH9 gene for a family featuring autosomal dominant May-Hegglin anomaly.</p><p><b>METHODS</b>Clinical and pathological features of all family members were analyzed. Blood samples were collected from the proband and other family members, and genomic DNA was extracted. Potential mutations of MYH9 gene exons 10, 25, 26, 30, 38 and 40 were screened with PCR and direct sequencing. After a mutation was identified in the proband, other affected members as well as healthy members from this family were analyzed with a pair of primers to amplify the mutant site. The PCR products were digested with Taq I enzyme and analyzed with agarose gel electrophoresis.</p><p><b>RESULTS</b>All affected members had bleeding tendency and typical features including giant platelets, thrombocytopenia and characteristic Dohle body-like leukocyte inclusions. A heterozygous missense mutation c.5521G>A (p.Glu1841Lys) in exon 38 of the MYH9 gene was identified in all affected members from this family.</p><p><b>CONCLUSION</b>The variant, c.5521G>A (p.Glu1841Lys) of MYH9, has co-segregated with the phenotype in the family. The mutant site is a hot spot in Chinese population.</p>
Subject(s)
Female , Humans , Male , Asian People , Genetics , Base Sequence , China , Exons , Genes, Dominant , Hearing Loss, Sensorineural , Molecular Motor Proteins , Genetics , Mutation , Myosin Heavy Chains , Genetics , Pedigree , Phenotype , Thrombocytopenia , Diagnosis , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To explore the method for early diagnosis and pathogenesis of MYH9-related syndrome through analysis of the clinical manifestation and gene mutation of a Chinese family with MYH9-related syndrome.</p><p><b>METHODS</b>Peripheral blood samples were collected from a three-generation Chinese family with MYH9-related syndrome (11 individuals, including 3 patients) and 100 healthy individuals. Polymerase chain reaction (PCR) amplification and direct sequencing of DNA were performed to analyze mutations of MYH9 gene.</p><p><b>RESULTS</b>Thrombocytopenia, increased volume of platelet, and granulocyte inclusion bodies were found in the patients with MYH9-related syndrome via a peripheral blood test. A missense mutation of a base pair (G-A) in exon 30 was revealed by PCR amplification and direct sequencing of MYH9 of the proband. That lead to Asp-Asn substitution at position 1424 (D1424N mutation). The mutation was the same as in other patients with MYH9-related syndrome. It was not found in healthy people from the Chinese family or in the other 100 healthy individuals.</p><p><b>CONCLUSIONS</b>Patients with MYH9-related syndrome show diverse symptoms. Mutation of MYH9 gene may be the molecular mechanism of MYH9-related syndrome, and D1424N mutation of MYH9 has not been reported in Chinese people. Early diagnosis of MYH9-related syndrome can be carried out by investigating family history and making early examinations.</p>
Subject(s)
Adult , Aged , Child, Preschool , Female , Humans , Asian People , Genetics , Molecular Motor Proteins , Genetics , Mutation , Myosin Heavy Chains , Genetics , Thrombocytopenia , GeneticsABSTRACT
In this report, we describe a Korean patient with May-Hegglin anomaly from a mutation of the MYH9 gene. The proband was a 21-year-old man with thrombocytopenia. He did not have a bleeding tendency. His neutrophil count was normal at 7490/mm3; however, the neutrophils contained abnormal basophilic inclusions in their cytoplasm. The platelet count was decreased at 15000/mm3 with giant platelets. Coagulation test results were not remarkable. Direct sequencing of MYH9 revealed that he was heterozygous for a mutation in exon 1, which was a 97T>A substitution mutation affecting codon 33, substituting tryptophan with arginine (Trp33Arg). Family study showed that both of his parents had normal phenotype and genotypes, indicating a de novo occurrence of the mutation in the proband.
Subject(s)
Adult , Humans , Male , Young Adult , Asian People , Exons/genetics , Molecular Motor Proteins/genetics , Mutation , Myosin Heavy Chains/genetics , Thrombocytopenia/geneticsABSTRACT
<p><b>OBJECTIVE</b>To investigate clinical features and to identify gene mutations in six patients with nonmuscle myosin heavy chain 9 gene (MYH9)-related disease.</p><p><b>METHODS</b>The platelet counts were measured using automated complete blood cell counter and manual manner. The size of platelets and inclusion bodies were observed under light microscopy. All the 40 exons and exon-intron boundaries of MYH9 gene were amplified by PCR and then DNA sequencing was performed. Restriction endonuclease analysis and polyacrylamide gel electrophoresis (PAGE) were used for polymorphism analysis.</p><p><b>RESULTS</b>Six patients all shared the common features of thrombocytopenia with giant platelets and granulocyte inclusions. Four MYH9 gene mutations were found in the six patients: T97C (W33R) in exon 1, 4335Insert CAGAAGAAG (1445InsQKK) and G4269A (D1424N) in exon 30 and G5833T (E1945Stop) in exon 40. The former two were novel mutations which have not been reported in the literature. The results of restriction endonuclease analysis and PAGE could exclude the possibility of nucleotide polymorphisms.</p><p><b>CONCLUSIONS</b>The MYH9 gene mutations were identified in six patients with MYH9 related disorders, and T97C (W33R) and 4335InsCAGAAGAAG (1445InsQKK) were novel mutations. MYH9 related disease should be considered in individuals with persistent thrombocytopenia which is non-responsive to corticosteroids and immuno-repressive agents.</p>
Subject(s)
Adolescent , Adult , Child , Female , Humans , Male , Middle Aged , Base Sequence , Inclusion Bodies , Molecular Motor Proteins , Genetics , Myosin Heavy Chains , Genetics , Phenotype , Sequence Analysis, DNA , Thrombocytopenia , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To improve the recognition of Fechtner syndrome.</p><p><b>METHODS</b>The clinical and laboratory data and family survey of a patient with Fechtner's syndrom was reported.</p><p><b>RESULTS AND CONCLUSION</b>Giant platelets, thrombocytopenia and characteristic granulocyte inclusion bodies (Döhle-like bodies) were found in both peripheral blood and bone marrow smears of the patient. Clinically the patient had renal damage, nervous deafness, and vitreous lesions. There was a family genetic tendency on family survey the diagnosis of Fechtner syndrome is established.</p>
Subject(s)
Humans , Male , Middle Aged , Hearing Loss, Sensorineural , Genetics , Molecular Motor Proteins , Genetics , Mutation , Myosin Heavy Chains , Genetics , Nephritis, Hereditary , Genetics , Thrombocytopenia , GeneticsABSTRACT
The migrating motor complex (MMC) occurs in most mammals and birds and is organized during the fetal life. In some species, like ruminants and other herbivores, it is not abolished by feeding but its character and controlling mechanisms do not vary considerably from other animal species. However, the mechanisms controlling the MMC are complex and incompletely recognized. The central nervous system exerts rather modulatory effects upon the MMC and the role of the enteric nervous system in the initiation and propagation of the MMC is crucial. The hormones appear mainly to disrupt and convert the MMC cycle into the fed pattern. Several types of the disturbances of the MMC cycle and its phases have been described in various pathophysiological conditions. However, it can be more suitable to identify and describe the given MMC abnormality than to establish the rules of the MMC behavior in the course of the gastrointestinal diseases.
Subject(s)
Animals , Biological Science Disciplines , Gastrointestinal Diseases/metabolism , Gastrointestinal Diseases/physiopathology , Gastrointestinal Tract/physiology , Models, Animal , Molecular Motor Proteins/metabolism , Protein TransportABSTRACT
<p><b>OBJECTIVES</b>To identify the nonmuscle myosin heavy chain 9 (MYH9) gene mutation site in a May-Hegglin anomaly(MHA) patient, and to analyze the genotype of her relatives to exclude the inherit correlation between the proband and her family members.</p><p><b>METHODS</b>Inclusion bodies in neutrophils of the proband were examined by transmission electron microscope, and giant platelets by scanning electron microscope. The mutation "hot spot" on the MYH9 gene of the proband and her family members was amplified with polymerase chain reaction(PCR), and then sequenced in both directions to identify the mutant site.</p><p><b>RESULTS</b>(1) The proband manifested with the typical MHA triad of giant platelet, thrombocytopenia and Dohle-like inclusion bodies in neutrophil. However, all of the proband's family members had no such anomaly. (2) Transmission electron microscope and scanning electron microscope confirmed that giant platelets and neutrophils inclusion bodies existed in the proband peripheral blood cells. (3) There was a missense mutation 5797 C-->T in the exon 40 of MYH9 gene which led to Arg changing into termination codon (Arg1933 stop). The proband also had a heterozygous mutation 4876A-->G in exon 33. There was no abnormal finding in the sites mentioned above in her mother, while her father carried the homozygous 4876A-->G mutation.</p><p><b>CONCLUSIONS</b>This MHA case is a sporadic one, in whose family a mode for autosomal dominant inheritance can not be established. The 5797C-->T substitution in MYH9 gene is a pathogenic mutation, however, 4876A-->G is simply a polymorphism.</p>
Subject(s)
Adult , Female , Humans , Hearing Loss, Sensorineural , Molecular Motor Proteins , Genetics , Mutation , Myosin Heavy Chains , Genetics , Polymorphism, Genetic , Thrombocytopenia , Blood , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To identify clinical and laboratory abnormalities and genetic defect of Fechtner syndrome in a Chinese family.</p><p><b>METHODS</b>The characteristic morphological features of platelets and leukocytes were examined on blood smears with Wright's-Giemsa staining and ultrastructure of platelet and leukocyte were investigated under electron microscope. Genomic DNA was isolated from peripheral blood of the proband and 9 members of his family. All the exons and exon-intron boundaries of the MYH9 gene were amplified by PCR followed by direct sequencing.</p><p><b>RESULTS</b>Patients presented the characteristic clinical features including macrothrombocytopenia, leukocyte inclusions and/or hereditary nephritis. A heterozygous C to T mutation was found in the proband and three members of his family at nucleotide 5981 in exon 40 of MYH9 gene, resulting in a nonsense mutation which encoded truncated protein due to premature termination at the Arg 1933 codon.</p><p><b>CONCLUSION</b>It is the first report of a Chinese family with Fechtner syndrome. The Arg (CGA) 1933--> stop (TGA) nonsense mutation in MYH9 gene is a causative genetic defect.</p>
Subject(s)
Adult , Humans , Male , Codon, Nonsense , DNA Mutational Analysis , Exons , Genetics , Inclusion Bodies , Genetics , Molecular Motor Proteins , Genetics , Myosin Heavy Chains , Genetics , Nephritis, Hereditary , Genetics , Pedigree , Syndrome , Thrombocytopenia , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To study the changes of platelet in May-Hegglin anomaly (MHA) and the molecular pathogenesis mechanism.</p><p><b>METHODS</b>Peripheral blood was drawn from the MHA proband, her father and her uncle. Platelet count and morphology were examined by automatic blood cell counter and microscopy, respectively. The platelet membrane protein was examined by flow cytometry. Membrane antibodies were determined by ELISA. PCR was used to amplify the exons 25, 31 approximately 32, 38 and 40 of the MYH 9 gene in the MHA patient and her diseased father. Furthermore, PCR products were sequenced, a specific point mutation was identified and inclusions (Dohle's body) in the neutrophil was detected by indirect immunofluorescence technique.</p><p><b>RESULTS</b>It was proved that in MHA patients, platelet count was higher by cell counter than by microscope (P < 0.01). Giant platelet was 94% but platelet membrane proteins (CD41, CD61, CD42A, CD42b) were in normal range. Membrane antibodies was undetectable. An A5521G mutation (GAG-->AAG) in the exon 38 was found in the proband and her diseased father, resulting in a characteristic change of NMMHC-A1841 (Glutamic acid-->Arginine), which was not found in other members of the family and in normal controls. Spindle-like inclusions with fluorescence were clearly displayed in neutrophil cytoplasm.</p><p><b>CONCLUSION</b>The molecular pathogenesis mechanism of May-Hegglin anomaly is the mutation in MYH 9 gene.</p>