Lack of CFAP54 causes primary ciliary dyskinesia in a mouse model and human patients / 医学前沿

Primary ciliary dyskinesia (PCD) is a highly heterogeneous recessive inherited disorder. FAP54, the homolog of CFAP54 in Chlamydomonas reinhardtii, was previously demonstrated as the C1d projection of the central microtubule apparatus of flagella. A Cfap54 knockout mouse model was then reported to have PCD-relevant phenotypes. Through whole-exome sequencing, compound heterozygous variants c.2649_2657delinC (p. E883Dfs*47) and c.7312_7313insCGCAGGCTGAATTCTTGG (p. T2438delinsTQAEFLA) in a new suspected PCD-relevant gene, CFAP54, were identified in an individual with PCD. Two missense variants, c.4112A>C (p. E1371A) and c.6559C>T (p. P2187S), in CFAP54 were detected in another unrelated patient. In this study, a minigene assay was conducted on the frameshift mutation showing a reduction in mRNA expression. In addition, a CFAP54 in-frame variant knock-in mouse model was established, which recapitulated the typical symptoms of PCD, including hydrocephalus, infertility, and mucus accumulation in nasal sinuses. Correspondingly, two missense variants were deleterious, with a dramatic reduction in mRNA abundance from bronchial tissue and sperm. The identification of PCD-causing variants of CFAP54 in two unrelated patients with PCD for the first time provides strong supportive evidence that CFAP54 is a new PCD-causing gene. This study further helps expand the disease-associated gene spectrum and improve genetic testing for PCD diagnosis in the future.

Novel mutation c.1210-3C > G in cis with a poly-T tract of 5T affects CFTR mRNA splicing in a Chinese patient with cystic fibrosis / 医学前沿

Cystic fibrosis (CF) is a rare autosomal recessive disease with only one pathogenic gene cystic fibrosis transmembrane conductance regulator (CFTR). To identify the potential pathogenic mutations in a Chinese patient with CF, we conducted Sanger sequencing on the genomic DNA of the patient and his parents and detected all 27 coding exons of CFTR and their flanking intronic regions. The patient is a compound heterozygote of c.2909G > A, p.Gly970Asp in exon 18 and c.1210-3C > G in cis with a poly-T of 5T (T5) sequence, 3 bp upstream in intron 9. The splicing effect of c.1210-3C > G was verified via minigene assay in vitro, indicating that wild-type plasmid containing c.1210-3C together with T7 sequence produced a normal transcript and partial exon 10-skipping-transcript, whereas mutant plasmid containing c.1210-3G in cis with T5 sequence caused almost all mRNA to skip exon 10. Overall, c.1210-3C > G, the newly identified pathogenic mutation in our patient, in combination with T5 sequence in cis, affects the CFTR gene splicing and produces nearly no normal transcript in vitro. Moreover, this patient carries a p.Gly970Asp mutation, thus confirming the high-frequency of this mutation in Chinese patients with CF.

Case report of neurofibromatosis type 1 combined with primary ciliary dyskinesia / 医学前沿

Neurofibromatosis (NF) is a genetic disease in which the lungs are rarely involved. However, in NF cases with lung involvement, chest computed tomography may show bilateral basal reticulations, apical bullae, and cysts without bronchiectasis. Herein, we report a patient diagnosed with NF on the basis of the results of genetic testing who presented with early-onset wet cough and bronchiectasis. Considering the differential diagnosis of bronchiectasis combined with his early-onset wet cough, sinusitis, and sperm quality decline, we considered the possibility of primary ciliary dyskinesia (PCD). Further electron microscopy analysis of cilia and identification of homozygous mutations in the RSPH4A gene confirmed the diagnosis of PCD. Therefore, for patients with NF, when an image change exists in the lungs that does not correspond to NF, the possibility of other diagnoses, including PCD, must be considered.

Clinical Features of Coccidioidomycosis:Analysis of 33 Chinese Cases / 中国医学科学院学报

Objective To summarize the characteristics of Chinese coccidioidomycosis cases, improve the diagnosis and treatment of this disease and prevent misdiagnosis as well as therapeutic error.Methods Search in databases including Medline,Wanfang,and CNKI using "Coccidioidomycosis" and "China" as index words yielded 23 articles that reported a total of 32 Chinese coccidioidomycosis cases.In addition,one patient with disseminated coccidioidomycos was treated in our center in April 2016.The demographic data,site of infection,clinical manifestations,past medical history,exposure history,imaging and laboratory findings,and pathological features of these 33 patients were analyzed.Results Among these 33 patients,7(21.2%)had visited an epidemic area and 6(18.2%)were immunocompromised.The disease involved the respiratory system,skin,bone,central nervous system,cornea,and stomach in 24,6,3,2,1,and 1 patients,respectively.Eight patients (24.2%) had multiple system involvement,and three of them died.The imaging findings included pulmonary nodules(=14),mediastinal lymphadenopathy(=5),solid shadow(=4),cavity(=4),pleural effusion(=3),multiple plaques(=2)and masses(=2).Coccidiolys cysts were detected in the affected tissues(=28)or in pus,exudate or pleural smear(=3);in addition,coccidioides mycelium and spores were found in the sputum,pus,and tissue cultures in 4 cases,among whom only 2 cases were confirmed by serological examination.The treatments included triazoles(=20),systemic or local administration of amphotericin B(=13),surgical resection of the lesion(=8),and intravenous gamma globulin(=1).Five patients died,among whom three had underlying diseases that caused immunosuppression and one was an infant.The prognoses were relatively good in the remaining patients.Conclusions Early diagnosis and proper treatment can achieve good prognosis in coccidioidomycosis patients.Multi-system involvement and immunosuppression are risk factors for poor prognosis of coccidioidomycosis.For these patients,adequate and full-course medication may prevent rapid disease progression.

Characteristics of serum lipid metabolism in patients with autoimmune pulmonary alveolar proteinosis / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the serum lipid panels in consecutive autoimmune pulmonary alveolar proteinosis(APAP)patients and analyze their relationship with anti-granulocyte macrophage-colony stimulating factor(GM-CSF)antibody and other markers.</p><p><b>METHODS</b>Thirty-two non-diabetic APAP patients were enrolled in the study. Serum lipids of these patients and 100 healthy volunteers were tested after an overnight fasting. Anti-GM-CSF antibody levels were measured with enzyme-linked immunosorbent assay. The correlation of serum lipids with lactate dehydrogenase,carcinoembryonic antigen,pulmonary function,and artery blood gas parameters were analyzed.</p><p><b>RESULTS</b>Total cholesterol and low-density lipoprotein cholesterol levels [(5.54±0.99)and(3.73±0.83)mmol/L respectively] were significantly higher in APAP patients than in healthy volunteers [(5.05±0.97)and(3.17±0.89)mmol/L respectively](all P<0.05). High-density lipoprotein cholesterol(HDL-C)level of the APAP group [(1.10±0.18)mmol/L ]was significantly lower than that of the healthy group(P<0.05). Low-density lipoprotein/HDL and total cholesterol/HDL ratios in the APAP group(3.47±0.90 and 5.14±1.12 respectively)were significantly higher than those in the healthy group[(2.63±0.87)and(4.18±1.12)](all P<0.05). There was no significant difference in triglyceride level between the two groups(P>0.05). HDL-C level was negatively correlated with alveolar-arterial oxygen pressure difference(r=-0.436,P<0.05)and positively correlated with arterial oxygen saturation(r=0.459,P<0.05). None of the lipid markers correlated with serum anti-GM-CSF antibody levels(all P>0.05).</p><p><b>CONCLUSIONS</b>APAP patients were likely to suffer from disturbed lipid metabolism,which was correlated with disease severity to some degree. Lipid markers deserved more attention in the management of APAP patients.</p>

Inactivation of mammalian target of rapamycin (mTOR) by rapamycin in a murine model of lipopolysaccharide-induced acute lung injury / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The mammalian target of rapamycin (mTOR) pathway, a key cellular signaling pathway associated with various cellular functions, has distinct roles in the inflammatory process. In this study, the mTOR inhibitor rapamycin (Rapa) was used to test whether inhibition of mTOR activation attenuates lipopolysaccharide (LPS)-induced acute lung injury (ALI) in a murine model.</p><p><b>METHODS</b>Mice pretreated with Rapa or vehicle were given LPS intratracheally. Local cell numbers and inflammatory cytokines present in the bronchoalveolar lavage fluid (BAL), wet-to-dry weight ratio, histopathology of the lungs, and survival were evaluated.</p><p><b>RESULTS</b>The phosphorylation of S6, a major downstream target of mTOR, had a 3-fold increase in lung tissue after LPS stimulation, but the increase was blocked by Rapa. Rapa reduced the levels of TNF-α (LPS vs. LPS + Rapa, (1672.74 ± 193.73) vs. (539.17 ± 140.48) pg/ml, respectively; P < 0.01) and IL-6 (LPS vs. LPS + Rapa: (7790.88 ± 1170.54) vs. (1968.57 ± 474.62) pg/ml, respectively; P < 0.01) in the BAL fluid. However, Rapa had limited effects on the overall severity of ALI, as determined by the wet-to-dry weight ratio of the lungs, number of neutrophils in the BAL fluid, and changes in histopathology. In addition, Rapa failed to reduce mortality in the LPS-induced ALI model.</p><p><b>CONCLUSIONS</b>We confirmed that mTOR was activated during LPS-induced ALI and strongly inhibited by Rapa. Although Rapa reduced the levels of the mediators of inflammation, the overall severity and survival of the ALI murine model were unchanged.</p>

The St. George's Respiratory Questionnaire in lymphangioleiomyomatosis / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To examine the correlation between the health-related quality of life measured by the St. George's Respiratory Questionnaire (SGRQ) and the commonly used physiological measures in lymphangioleiomyomatosis (LAM).</p><p><b>METHODS</b>This study retrospectively analyzed the SGRQ scores and other measures (the Borg scale of breathlessness at rest, 6-minute walking distance, blood oxygen levels, and pulmonary function) of patients diagnosed and confirmed with LAM. Altogether 38 patients between June 2007 and November 2009 were included.</p><p><b>RESULTS</b>The mean values of the SGRQ three components (symptoms, activity, and impacts) and total scores in the LAM patients were 46.95 +/- 28.90, 58.47 +/- 25.41, 47.89 +/- 29.66, and 51.11 +/- 26.35, respectively. The SGRQ total or component scores were correlated well with the Borg scale of breathlessness, 6-minute walking distance, partial pressure of oxygen in arterial blood, spirometry and diffusion capacity of lung. There were poor correlations between SGRQ score and residual volume or total lung capacity. In our preliminary observation, sirolimus improved the SGRQ total and three component scores and the Borg scale of breathlessness significantly after 101-200 days of treatment (n = 6).</p><p><b>CONCLUSIONS</b>The SGRQ score in LAM is correlated well with physiological measures (Borg scale of breathlessness, 6-minute walking distance, blood oxygen levels, and pulmonary function tests). The SGRQ could therefore be recommended in baseline and follow-up evaluation of patients with LAM. Treatment with sirolimus, an inhibitor of mammalian target of rapamycin, may improve the quality of life and patient's perception of breathlessness in LAM.</p>

Humidification during mechanical ventilation / 中国医学科学院学报

This review aims to emphasize the importance of humidification and to identify humidification method the most effective in the intubated or ventilated patients. Some details are also discussed on how to perform humidification.