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.

Degradation of SARS-CoV-2 receptor ACE2 by tobacco carcinogen-induced Skp2 in lung epithelial cells

An unexpected observation among the COVID-19 pandemic is that smokers constituted only 1.4-18.5% of hospitalized adults, calling for an urgent investigation to determine the role of smoking in SARS-CoV-2 infection. Here, we show that cigarette smoke extract (CSE) and carcinogen benzo(a)pyrene (BaP) increase ACE2 mRNA but trigger ACE2 protein catabolism. BaP induces an aryl hydrocarbon receptor (AhR)-dependent upregulation of the ubiquitin E3 ligase Skp2 for ACE2 ubiquitination. ACE2 in lung tissues of non-smokers is higher than in smokers, consistent with the findings that tobacco carcinogens downregulate ACE2 in mice. Tobacco carcinogens inhibit SARS-CoV-2 Spike protein pseudovirions infection of the cells. Given that tobacco smoke accounts for 8 million deaths including 2.1 million cancer deaths annually and Skp2 is an oncoprotein, tobacco use should not be recommended and cessation plan should be prepared for smokers in COVID-19 pandemic.

Anti-hypertensive Angiotensin II receptor blockers associated to mitigation of disease severity in elderly COVID-19 patients

BackgroundThe novel coronavirus (CoV) severe acute respiratory syndrome (SARS)-CoV-2 outbreak started at the end of 2019 in Wuhan, China, and spread over 100 countries. SARS-CoV-2 uses the membrane protein Angiotensin I converting enzyme 2(ACE2) as a cell entry receptor. Indeed, it was reported that the balance of Renin-Angiotensin System (RAS), regulated by both ACE and ACE2, was altered in COVID-19 patients. It is controversial, however, whether commonly used anti-hypertensive drugs Angiotensin I converting enzyme inhibitor (ACEI) and Angiotensin II receptor blocker (ARB) shall be continued in the confirmed COVID-19 patients. This study was designed to investigate any difference in disease severity between COVID-19 patients with hypertension comorbidity. The included COVID-19 patients used ACEI, ARB, calcium channel blockers (CCB), beta blockers (BB), or thiazide to treat preexisting hypertension prior to the hospital were compared to patients who did not take any of those drugs. MethodsIn this multicentre retrospective study, clinical data of 511 COVID-19 patients were analyzed. Patients were categorized into six sub-groups of hypertension comorbidity based on treatment using one of anti-hypertension drugs (ACEI, ARB, CCB, BB, thiazide), or none. A meta-analysis was performed to evaluate the use of ACEI and ARB associated with pneumonia using published studies. FindingsAmong the elderly (age>65) COVID-19 patients with hypertension comorbidity, the risk of COVID-19-S (severe disease) was significantly decreased in patients who took ARB drugs prior to hospitalization compared to patients who took no drugs (OR=0{middle dot}343, 95% CI 0{middle dot}128-0{middle dot}916, p=0{middle dot}025). The meta-analysis showed that ARB use has positive effects associated with morbidity and mortality of pneumonia. InterpretationElderly (age>65) COVID-19 patients with hypertension comorbidity who are taking ARB anti-hypertension drugs may be less likely to develop severe lung disease compared to patients who take no anti-hypertension drugs. FundingNational Natural Science Foundation of China, Chinese Academy of Medical Sciences Research in contextO_ST_ABSEvidence before this studyC_ST_ABSWe searched PubMed for articles published up to March 15, 2020 using keywords "2019-nCoV", "SARS-CoV-2", "novel coronavirus", and COVID-19 AND "ARB", and "angiotensin II receptor blocker" for papers published in both English and Chinese. We found three papers: one from our group, published in Science China Life Science that demonstrated an elevated Angiotensin II level in blood samples from COVID-19 patients; another a perspective article in Chinese recommending ACEI and ARBs as potential remedies for SARS-CoV-2 infections; the third a retrospective study in Chinese identifying no significant difference between ACEI/ARB associated with outcomes in 112 COVID-19 patients with CVD comorbidity. The International society of Hypertension stated on March 16th, 2020: "there are no clinical data in human to show that ACE-inhibitors or ARBs either improve or worsen susceptibility to COVID-19 infection nor do they affect the outcomes of those infected". Added value of this studyWe retrospectively reviewed different types of anti-hypertensive drugs taken by COVID-19 patients with hypertension comorbidity prior to entering the hospital. We discovered that ARB hypertensive drugs were associated with a decreased risk of severe disease in elderly (age>65) COVID-19 patients (OR=0{middle dot}343, 95% CI 0{middle dot}128-0{middle dot}916, p=0{middle dot}025), the first evidence of ARBs association to COVID-19 infections in human. We conducted a meta-analysis in the literature and found that ARB has positive effects associated with morbidity and mortality of pneumonia. Implications of all the available evidenceARB drugs are widely used in the population with hypertension. Treatments with ACEI and ARBs should be continuous according to medical guidelines. RCT trials of ARB associated with morbidity and mortality of SARS-CoV-2 infection are recommended in the future.

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.