Browsing by Author "Hu, Xinhua"

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    Consensus interpretation of the p.Met34Thr and p.Val37Ile variants in GJB2 by the ClinGen Hearing Loss Expert Panel
    (Springer Nature, 2019-11) Shen, Jun; Oza, Andrea M.; Del Castillo, Ignacio; Duzkale, Hatice; Matsunaga, Tatsuo; Pandya, Arti; Kang, Hyunseok P.; Mar-Heyming, Rebecca; Guha, Saurav; Moyer, Krista; Lo, Christine; Kenna, Margaret; Alexander, John J.; Zhang, Yan; Hirsch, Yoel; Luo, Minjie; Cao, Ye; Choy, Kwong Wai; Cheng, Yen-Fu; Avraham, Karen B.; Hu, Xinhua; Garrido, Gema; Moreno-Pelayo, Miguel A.; Greinwald, John; Zhang, Kejian; Zeng, Yukun; Brownstein, Zippora; Basel-Salmon, Lina; Davidov, Bella; Frydman, Moshe; Weiden, Tzvi; Nagan, Narasimhan; Willis, Alecia; Hemphill, Sarah E.; Grant, Andrew R.; Siegert, Rebecca K.; DiStefano, Marina T.; Amr, Sami S.; Rehm, Heidi L.; Abou Tayoun, Ahmad N.; Clin Gen Hearing Loss Working Group; Biostatistics, School of Public Health
    Purpose: Pathogenic variants in GJB2 are the most common cause of autosomal recessive sensorineural hearing loss. The classification of c.101T>C/p.Met34Thr and c.109G>A/p.Val37Ile in GJB2 are controversial. Therefore, an expert consensus is required for the interpretation of these two variants. Methods: The ClinGen Hearing Loss Expert Panel collected published data and shared unpublished information from contributing laboratories and clinics regarding the two variants. Functional, computational, allelic, and segregation data were also obtained. Case-control statistical analyses were performed. Results: The panel reviewed the synthesized information, and classified the p.Met34Thr and p.Val37Ile variants utilizing professional variant interpretation guidelines and professional judgment. We found that p.Met34Thr and p.Val37Ile are significantly overrepresented in hearing loss patients, compared with population controls. Individuals homozygous or compound heterozygous for p.Met34Thr or p.Val37Ile typically manifest mild to moderate hearing loss. Several other types of evidence also support pathogenic roles for these two variants. Conclusion: Resolving controversies in variant classification requires coordinated effort among a panel of international multi-institutional experts to share data, standardize classification guidelines, review evidence, and reach a consensus. We concluded that p.Met34Thr and p.Val37Ile variants in GJB2 are pathogenic for autosomal recessive nonsyndromic hearing loss with variable expressivity and incomplete penetrance.
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    Transhemispheric cortex remodeling promotes forelimb recovery after spinal cord injury
    (American Society for Clinical Investigation, 2022-06-22) Wu, Wei; Nguyen, Tyler; Ordaz, Josue D.; Zhang, Yiping; Liu, Nai-Kui; Hu, Xinhua; Liu, Yuxiang; Ping, Xingjie; Han, Qi; Wu, Xiangbing; Qu, Wenrui; Gao, Sujuan; Shields, Christopher B.; Jin, Xiaoming; Xu, Xiao-Ming; Neurological Surgery, School of Medicine
    Understanding the reorganization of neural circuits spared after spinal cord injury in the motor cortex and spinal cord would provide insights for developing therapeutics. Using optogenetic mapping, we demonstrated a transhemispheric recruitment of neural circuits in the contralateral cortical M1/M2 area to improve the impaired forelimb function after a cervical 5 right-sided hemisection in mice, a model mimicking the human Brown-Séquard syndrome. This cortical reorganization can be elicited by a selective cortical optogenetic neuromodulation paradigm. Areas of whisker, jaw, and neck, together with the rostral forelimb area, on the motor cortex ipsilateral to the lesion were engaged to control the ipsilesional forelimb in both stimulation and nonstimulation groups 8 weeks following injury. However, significant functional benefits were only seen in the stimulation group. Using anterograde tracing, we further revealed a robust sprouting of the intact corticospinal tract in the spinal cord of those animals receiving optogenetic stimulation. The intraspinal corticospinal axonal sprouting correlated with the forelimb functional recovery. Thus, specific neuromodulation of the cortical neural circuits induced massive neural reorganization both in the motor cortex and spinal cord, constructing an alternative motor pathway in restoring impaired forelimb function.