Dynein axonemal heavy chain 10 deficiency causes primary ciliary dyskinesia in humans and mice / 医学前沿

Primary ciliary dyskinesia (PCD) is a congenital, motile ciliopathy with pleiotropic symptoms. Although nearly 50 causative genes have been identified, they only account for approximately 70% of definitive PCD cases. Dynein axonemal heavy chain 10 (DNAH10) encodes a subunit of the inner arm dynein heavy chain in motile cilia and sperm flagella. Based on the common axoneme structure of motile cilia and sperm flagella, DNAH10 variants are likely to cause PCD. Using exome sequencing, we identified a novel DNAH10 homozygous variant (c.589C > T, p.R197W) in a patient with PCD from a consanguineous family. The patient manifested sinusitis, bronchiectasis, situs inversus, and asthenoteratozoospermia. Immunostaining analysis showed the absence of DNAH10 and DNALI1 in the respiratory cilia, and transmission electron microscopy revealed strikingly disordered axoneme 9+2 architecture and inner dynein arm defects in the respiratory cilia and sperm flagella. Subsequently, animal models of Dnah10-knockin mice harboring missense variants and Dnah10-knockout mice recapitulated the phenotypes of PCD, including chronic respiratory infection, male infertility, and hydrocephalus. To the best of our knowledge, this study is the first to report DNAH10 deficiency related to PCD in human and mouse models, which suggests that DNAH10 recessive mutation is causative of PCD.

Clinical phenotypes of primary ciliary dyskinesia / 中南大学学报(医学版)

Primary ciliary dyskinesia (PCD) is a hereditary disease characterized by airway mucociliary clearance dysfunction. The estimated prevalence of PCD is 1꞉10 000 to 1꞉20 000. The main respiratory manifestations in children are cough, expectoration, chronic rhinitis, sinusitis, and chronic otitis media, while the most common symptoms in adults are chronic sinusitis, bronchiectasis, and infertility. About 50% of patients with certain PCD-related gene variants are combined with situs inversus, and the incidence of congenital heart disease is also high. The pathogenesis behind PCD is that gene variants cause structural or functional disorders of respiratory cilia and motile cilia of other organs, leading to a series of heterogeneous clinical manifestations, which makes it difficult to identify and diagnose PCD. Combining different disease screening tools and understanding the relationship between genotypes and phenotypes may facilitate early diagnosis and treatment for PCD.

Epidemiological and clinical features of 291 cases with coronavirus disease 2019 in areas adjacent to Hubei, China: a double-center observational study

BackgroundThe clinical outcomes of COVID-19 patients in Hubei and other areas are different. We aim to investigate the epidemiological and clinical characteristics of patient with COVID-19 in Hunan which is adjacent to Hubei. MethodsIn this double-center, observational study, we recruited all consecutive patients with laboratory confirmed COVID-19 from January 23 to February 14, 2020 in two designated hospitals in Hunan province, China. Epidemiological and clinical data from patients electronic medical records were collected and compared between mild, moderate and severe/critical group in detail. Clinical outcomes were followed up to February 20, 2020. Findings291 patients with COVID-19 were categorized into mild group (10.0%), moderate group (72.8%) and severe/critical group (17.2%). The median age of all patients was 46 years (49.8% were male). 86.6% patients had an indirect exposure history. The proportion of patients that had been to Wuhan in severe/critical group (48.0% vs 17.2%, p=0.006) and moderate group (43.4% vs 17.2%, p=0.007) were higher than mild group. Fever (68.7%), cough (60.5%), and fatigue (31.6%) were common symptoms especially for severe and critical patients. Typical lung imaging finding were bilateral and unilateral ground glass opacity or consolidation. Leukopenia, lymphopenia and eosinopenia occurred in 36.1%, 22.7% and 50.2% patients respectively. Increased fibrinogen was detected in 45 of 58 (77.6%) patients with available results. 29 of 44 (65.9%) or 22 of 40 (55.0%) patients were positive in Mycoplasma pneumonia or Chlamydia pneumonia antibody test respectively. Compared with mild or moderate group, severe/critical group had a relative higher level of neutrophil, Neutrophil-to-Lymphocyte Ratio, h-CRP, ESR, CK, CK-MB, LDH, D-dimer, and a lower level of lymphocyte, eosinophils, platelet, HDL and sodium (all p<0.01). Most patients received antiviral therapy and Chinese Medicine therapy. As of February 20, 2020, 159 (54.6%) patients were discharged and 2 (0.7%) patients died during hospitalization. The median length of hospital stay in discharged patients was 12 days (IQR: 10-15). InterpretationThe epidemiological and clinical characteristics of COVID-19 patients in Hunan is different from patients in Wuhan. The proportion of patients that had been to Wuhan in severe/critical group and moderate group were higher than mild group. Laboratory and imaging examination can assist in the diagnosis and classification of COVID-19 patients.