Objectives: Auditory neuropathy (AN) is a sensorineural hearing disorder characterized by absent or abnormal auditory brainstem responses (ABRs) and normal cochlear outer hair cell function as measured by otoacoustic ...Objectives: Auditory neuropathy (AN) is a sensorineural hearing disorder characterized by absent or abnormal auditory brainstem responses (ABRs) and normal cochlear outer hair cell function as measured by otoacoustic emissions (OAEs). Many risk factors are thought to be involved in its etiology and pathophysiology. Three Chinese pedigrees with familial AN are presented herein to demonstrate involvement of genetic factors in AN etiology. Methods: Probands of the above - mentioned pedigrees, who had been diagnosed with AN, were evaluated and followed up in the Department of Otolaryngology Head and Neck Surgery, China PLA General Hospital. Their family members were studied and the pedigree diagrams were established. History of illness, physical examination,pure tone audiometry, acoustic reflex, ABRs and transient evoked and distortion- product otoacoustic emissions (TEOAEs and DPOAEs) were obtained from members of these families. DPOAE changes under the influence of contralateral sound stimuli were observed by presenting a set of continuous white noise to the non - recording ear to exam the function of auditory efferent system. Some subjects received vestibular caloric test, computed tomography (CT)scan of the temporal bone and electrocardiography (ECG) to exclude other possible neuropathy disorders. Results: In most affected subjects, hearing loss of various degrees and speech discrimination difficulties started at 10 to16 years of age. Their audiological evaluation showed absence of acoustic reflex and ABRs. As expected in AN, these subjects exhibited near normal cochlear outer hair cell function as shown in TEOAE & DPOAE recordings. Pure- tone audiometry revealed hearing loss ranging from mild to severe in these patients. Autosomal recessive inheritance patterns were observed in the three families. In Pedigree Ⅰ and Ⅱ, two affected brothers were found respectively, while in pedigree Ⅲ, 2 sisters were affected. All the patients were otherwise normal without evidence of peripheral neuropathy at the time of this writing. Conclusions: In this study, patients with feature of non- syndromic hereditary auditory neuropathy were identified in three Chinese families.Pedigree analysis indicates autosomal recessive inheritances in the pedigrees. The observed inheritance and clinical audiologic findings are different from those previously described for non-syndromic low-frequency sensorineural hearing loss. This information should facilitate future molecular candidate genes screening for understanding the mechanism of AN.展开更多
Hemophilia B, affecting 1 in 30000 males, is aserious X-linked recessive bleeding disorder due to apartial or complete deficiency of human clottingfactor Ⅸ (hFⅨ) activity in the plasma. Conventionaltherapy depends o...Hemophilia B, affecting 1 in 30000 males, is aserious X-linked recessive bleeding disorder due to apartial or complete deficiency of human clottingfactor Ⅸ (hFⅨ) activity in the plasma. Conventionaltherapy depends on the infusion of human plasma orconcentrate. The therapeutic effect is temporary展开更多
Upland cotton is one of the important cultivatedallotetraploid species.From the point offunctional genomic research,it is hard to obtainhomozygous recessive mutants by applying oftraditional mutagensis methods in this...Upland cotton is one of the important cultivatedallotetraploid species.From the point offunctional genomic research,it is hard to obtainhomozygous recessive mutants by applying oftraditional mutagensis methods in this crop as itsmany traits are controlled by more than twopairs of alleles. Adopting of specific展开更多
Japanese Prime Minister Morihiro Hosokawa promised on March 7 economic reform, a recovery from recession and voluntary measures to open markets and calm a US trade row as he fought opposition charges of incompetence.
基金a grant from the National High Tech Development Project(2001AA221092)and by Beijing Natural Science Foundation(No.7011004)and Beijing Science and Technology Innovation Project(No.H010210160119)grants
文摘Objectives: Auditory neuropathy (AN) is a sensorineural hearing disorder characterized by absent or abnormal auditory brainstem responses (ABRs) and normal cochlear outer hair cell function as measured by otoacoustic emissions (OAEs). Many risk factors are thought to be involved in its etiology and pathophysiology. Three Chinese pedigrees with familial AN are presented herein to demonstrate involvement of genetic factors in AN etiology. Methods: Probands of the above - mentioned pedigrees, who had been diagnosed with AN, were evaluated and followed up in the Department of Otolaryngology Head and Neck Surgery, China PLA General Hospital. Their family members were studied and the pedigree diagrams were established. History of illness, physical examination,pure tone audiometry, acoustic reflex, ABRs and transient evoked and distortion- product otoacoustic emissions (TEOAEs and DPOAEs) were obtained from members of these families. DPOAE changes under the influence of contralateral sound stimuli were observed by presenting a set of continuous white noise to the non - recording ear to exam the function of auditory efferent system. Some subjects received vestibular caloric test, computed tomography (CT)scan of the temporal bone and electrocardiography (ECG) to exclude other possible neuropathy disorders. Results: In most affected subjects, hearing loss of various degrees and speech discrimination difficulties started at 10 to16 years of age. Their audiological evaluation showed absence of acoustic reflex and ABRs. As expected in AN, these subjects exhibited near normal cochlear outer hair cell function as shown in TEOAE & DPOAE recordings. Pure- tone audiometry revealed hearing loss ranging from mild to severe in these patients. Autosomal recessive inheritance patterns were observed in the three families. In Pedigree Ⅰ and Ⅱ, two affected brothers were found respectively, while in pedigree Ⅲ, 2 sisters were affected. All the patients were otherwise normal without evidence of peripheral neuropathy at the time of this writing. Conclusions: In this study, patients with feature of non- syndromic hereditary auditory neuropathy were identified in three Chinese families.Pedigree analysis indicates autosomal recessive inheritances in the pedigrees. The observed inheritance and clinical audiologic findings are different from those previously described for non-syndromic low-frequency sensorineural hearing loss. This information should facilitate future molecular candidate genes screening for understanding the mechanism of AN.
文摘Hemophilia B, affecting 1 in 30000 males, is aserious X-linked recessive bleeding disorder due to apartial or complete deficiency of human clottingfactor Ⅸ (hFⅨ) activity in the plasma. Conventionaltherapy depends on the infusion of human plasma orconcentrate. The therapeutic effect is temporary
文摘Upland cotton is one of the important cultivatedallotetraploid species.From the point offunctional genomic research,it is hard to obtainhomozygous recessive mutants by applying oftraditional mutagensis methods in this crop as itsmany traits are controlled by more than twopairs of alleles. Adopting of specific
文摘Japanese Prime Minister Morihiro Hosokawa promised on March 7 economic reform, a recovery from recession and voluntary measures to open markets and calm a US trade row as he fought opposition charges of incompetence.
