[Genome sequence analysis of two SARS-CoV-2 virus infections in Inner Mongolia, 2022].

The target gene sequences of the novel coronaviruses obtained by sequencing were compared with the reference sequences to analyze the genetic variation of the two cases of the novel coronaviruses from Inner Mongolia Autonomous Region in 2022 and to explore the sources of infection. The results showed that the two sequences belonged to different evolutionary branches, Delta (AY.122) and Omicron (BA.1.1), respectively. hCoV-19/Inner Mongolia/IVDC-591/2022 had 48 single nucleotide polymorphisms on the genome sequences, sharing 40 nucleotide mutation sites with a Mongolian strain; hCoV-19/Inner Mongolia/IVDC-592/2022 genome shared 57 nucleotide mutation sites with a UK strain, and the nucleotide mutation site identity was 100% (57/57). Phylogenetic analysis showed that the target gene sequences were not directly related to domestic novel coronavirus sequences during the same period, but were related to isolates from Europe and Mongolia.

[Autophagy regulates multiple organ injury in obstructive sleep apnea and its related mechanisms].

Obstructive sleep apnea is a sleep-related hypoxia/reoxygenation syndrome that can lead to cardiovascular and cerebrovascular diseases, glucose and lipid metabolism, nervous system and even multiple organ damage, and is a serious threat to human health. Autophagy is a process by which eukaryotic cells rely on the lysosome pathway to degrade abnormal proteins and organelles, maintain homeostasis of intracellular environment and achieve self-renewal. Many studies have found that obstructive sleep apnea causes damage to myocardial, hippocampus, kidney and other organs, and its mechanism may be related to autophagy.

[The role of Müller cells in the formation and development of macular hole].

Müller cells are important glial cells in the retina, which play important roles in maintaining the stability of the retina by mechanical support, homeostasis, and physiological metabolism, as well as protecting photoreceptor cells and retinal pigment epithelial cells. The degeneration and destruction of Müller cells are often accompanied by various retinal diseases, and the function of Müller cells is changed under pathological conditions. Based on the summary of the morphology, distribution and function of Müller cells, this article analyzes the different manifestations and changes of Müller cells in different stages of macular hole and the closely related mechanisms, aiming to clarify the role of Müller cells in the formation and development of macular hole and to provide reference for the prediction of disease progression and guidance of treatment.(This article was published ahead of print on the official website of Chinese Journal of Ophthalmology on Augest 28, 2023).

Keratinocytes: innate immune cells in atopic dermatitis.

The skin is a unique immune organ that constitutes a complex network of physical, chemical and microbiological barriers against external insults. Keratinocytes are the most abundant cell type in the epidermis. These cells form the physical skin barrier and represent the first line of the host defense system by sensing pathogens via innate immune receptors, initiating anti-microbial responses and producing various cytokines, chemokines and anti-microbial peptides, which are important events in immunity. A damaged epidermal barrier in atopic dermatitis allows the penetration of potential allergens and pathogens to activate keratinocytes. Among the dysregulation of immune responses in atopic dermatitis, activated keratinocytes play a role in several biological processes that contribute to the pathogenesis of atopic dermatitis. In this review, we summarize the current understanding of the innate immune functions of keratinocytes in the pathogenesis of atopic dermatitis, with a special emphasis on skin-derived anti-microbial peptides and atopic dermatitis-related cytokines and chemokines in keratinocytes. An improved understanding of the innate immunity mediated by keratinocytes can provide helpful insight into the pathophysiological processes of atopic dermatitis and support new therapeutic efforts.

Cholesterol 24S-Hydroxylase overexpression increases the lipid droplet formation of human umbilical cord mesenchymal stem cells but does not affect adipocyte differentiation.

Dysregulation of the adipo-osteogenic differentiation balance of mesenchymal stem cells (MSCs), which are common progenitor cells of adipocytes and osteoblasts, has been associated with many pathophysiologic diseases, such as obesity, osteopenia, and several neurodegenerative disorders. Growing evidence suggests that lipid metabolism is crucial for maintaining stem cell homeostasis and cell differentiation, however, the detailed underlying mechanisms are largely unknown. In this study, we demonstrate that CYP46A1 genes are key determinants of MSC increasing lipid droplet formation. Brain cholesterol is synthesized in situ and cannot cross the blood-brain barrier: to be exported from the central nervous system into the blood circuit, excess cholesterol must be converted to 24S-hydroxycholesterol by the cholesterol 24-hydroxylase encoded by the CYP46A1 gene. To address this issue, we used an adenoassociated virus (AAV) gene transfer strategy to increase CYP46A1 expression in order to investigate the consequences on the human mesenchymal stem cell (hU-MSCs). CYP46A1 expression was assessed with Western blotting and quantitative reverse transcription PCR. We found that CYP46A1 expression was increased during adipogenesis, and treatment with exogenous CYP46A1 increased adipogenesis. Thus, we hypothesize that CYP46A1 overexpression in hU-MSCs would significantly enhance cholesterol turnover in the brain of hypoxic-ischemic encephalopathy (HIE). CYP46A1 can potentially serve as a specific target to modify the therapeutic and biological effects of hU-MSCs on HIE patients.

[Preliminary study of the relationship between novel coronavirus pneumonia and liver function damage: a multicenter study].

Objective: To analyze the clinical characteristics of cases of novel coronavirus pneumonia and a preliminary study to explore the relationship between different clinical classification and liver damage. Methods: Consecutively confirmed novel coronavirus infection cases admitted to seven designated hospitals during January 23, 2020 to February 8, 2020 were included. Clinical classification (mild, moderate, severe, and critical) was carried out according to the diagnosis and treatment program of novel coronavirus pneumonia (Trial Fifth Edition) issued by the National Health Commission. The research data were analyzed using SPSS19.0 statistical software. Quantitative data were expressed as median (interquartile range), and qualitative data were expressed as frequency and rate. Results: 32 confirmed cases that met the inclusion criteria were included. 28 cases were of mild or moderate type (87.50%), and four cases (12.50%) of severe or critical type. Four cases (12.5%) were combined with one underlying disease (bronchial asthma, coronary heart disease, malignant tumor, chronic kidney disease), and one case (3.13%) was simultaneously combined with high blood pressure and malignant tumor. The results of laboratory examination showed that the alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin (ALB), and total bilirubin (TBil) for entire cohort were 26.98 (16.88 ~ 46.09) U/L and 24.75 (18.71 ~ 31.79) U/L, 39.00 (36.20 ~ 44.20) g/L and 16.40 (11.34 ~ 21.15) µmol/L, respectively. ALT, AST, ALB and TBil of the mild or moderate subgroups were 22.75 (16.31 ~ 37.25) U/L, 23.63 (18.71 ~ 26.50) U/L, 39.70 (36.50 ~ 46.10) g/L, and 15.95 (11.34 ~ 20.83) µmol/L, respectively. ALT, AST, ALB and TBil of the severe or critical subgroups were 60.25 (40.88 ~ 68.90) U/L, 37.00 (20.88 ~ 64.45) U/L, 35.75 (28.68 ~ 42.00) g/L, and 20.50 (11.28 ~ 25.00) µmol/L, respectively. Conclusion: The results of this multicenter retrospective study suggests that novel coronavirus pneumonia combined with liver damage is more likely to be caused by adverse drug reactions and systemic inflammation in severe patients receiving medical treatment. Therefore, liver function monitoring and evaluation should be strengthened during the treatment of such patients.

[Systematic evaluation and Meta-analysis of efficacy and safety of Tianzhi Granules in treatment of vascular cognitive impairment].

Tianzhi Granules has effects in calming liver wind, nourishing liver and kidney and activating blood. At present, it is used for treatment of vascular cognitive impairment. However, its efficacy and safety remained to be verified. Therefore, this study aims to systematically analyze the efficacy and safety of Tianzhi Granules in the treatment of vascular cognitive impairment. CNKI, VIP, WanFang, SinoMed, PubMed and Cochrane Library, ClinicalTrials.gov were retrieved to screen out relevant randomized controlled trials about the effect of Tianzhi Granules on vascular cognitive impairment according to the inclusion criteria. Two researchers independently used the risk of bias assessment tool for quality assessment, and extracted and checked the data. Cochrane systematic evaluation software RevMan 5.3 was used for data analysis. Twenty-seven articles involving 2 741 subjects were included. The intervention measure was Tianzhi Granules alone, and the control measure was Western medicine alone or blank control. According to the results, Tianzhi Granules was better than blank control and brain metabolism promoter in clinical efficacy rate and improvement of MMSE score. And it was better than blank control and nimodipine in the improvement of event-related potential(ERP) P300. Within 3 months, Tianzhi Granules had better effects than Western medicine group and blank group, with a low incidence of adverse events. Tianzhi Granules can be recommended for clinical use. However, due to the low quality of the include literatures, these potential benefits need to be confirmed in future standardized clinical trials with a large sample size.

[Preparation and pharmacodynamics in vivo of nano graphene oxide-based matrine in situ gel].

With matrine(MAT) as the model drug, to prepare nano graphene oxide(NGO)-based MAT in situ gel(MAT-NGO-gel), a kind of drug for tumor treatment in combination with phototheraphy, and investigate the physicochemical properties and anti-tumor effects in vivo of MAT-NGO-gel. First, HPLC method was established to measure the content of MAT in the gel. The ultrasonic method was used to load MAT onto the surface of NGO, and then poloxamer 188 and poloxamer 407 were chosen as the main materials to prepare MAT-NGO-gel. The optimum prescription was selected with the gelation temperature as the index. Finally, the drug loading rate, micromorphology, phototherrmal conversion characteristics and drug release in vitro of MAT-NGO-gel were characterized. In the optimized prescription, the concentration of poloxamer 188 and poloxamer 407 was 2% and 20% respectively, and the mass ratio of NGO and MAT was 1∶1. The gelation temperature and drug loading rate of MAT-NGO-gel prepared by the optimal prescription process was 37.5 ℃ and 16.7%. Under 808 nm laser irradiation, MAT-NGO-gel showed obvious concentration-and time-dependent photothermal conversion characteristics. In vitro release experiments showed that MAT-NGO-gel had temperature-dependent release characteristics. The pharmacodynamics of MAT solution, NGO-gel and MAT-NGO-gel were studied by using S180 tumor-bearing mice and 808 nm laser. The relative tumor volume and body weight of the tumor-bearing mice were plotted over time. After the experiment, the tumor tissues of each group were taken and the histopathological changes were observed by HE staining. The results of pharmacodynamic studies demonstrated that when compared with NS group and NGO-gel group, the body weights of mice in MAT-NGO-gel group and MAT-NGO-gel + laser group were higher, and the relative tumor volume growth was slower. The results of HE stained pathological sections showed that the tumor cells count for the mice in MAT-NGO-gel group and MAT-NGO-gel + laser group was significantly reduced, with obvious nuclear fragmentation and nucleolysis in these two groups. These results suggested that MAT-NGO-gel, especially combined with 808 nm laser, had stronger anti-tumor activity in vivo. The prescription process of MAT-NGO-gel in this experiment was stable and feasible. As compared with MAT solution, MAT-NGO-gel showed obvious sustained and temperature-dependent drug release characteristics. MAT-NGO-gel had much more obvious anti-tumor activity in vivo when combined with 808 nm laser irradiation. This study could provide certain theoretical basis for the therapy of malignant tumor with multiple mechanisms.

[A clinical study of Proteus syndrome caused by a mosaic somatic mutation in AKT1 gene].

Objective: Proteus syndrome is a rare disease. The aim of the present study was to analyze the clinical characteristics and gene mutations of Proteus syndrome with a case report and relevant literature review. Methods: Clinical data of the patient with Proteus syndrome were collected in detail and biochemical measurements and radiological examinations were conducted. Tissues from phalanges with lesions were obtained to extract DNA, and Sanger sequencing of AKT1 gene was carried on. The pathogenic mutation was further tested in peripheral blood samples of the patient, his parents and 250 healthy volunteers. Orthopaedic surgery was performed on the affected limbs of the patient. Results: The patient was presented with progressive overgrowth of the right extremity, scoliosis, cerebral connective tissue nevus and lower extremity venous. A heterozygous mutation of AKT1 gene (c. 49G>A) was identified in DNA extracted from the affected bone tissue of the patient, but not be found in genomic DNA of peripheral blood samples from the patient, his parents and 250 healthy volunteers. Movement function of the affected limb improved significantly after the operations. Conclusions: The prominent features of Proteus syndrome are overgrowth of one extremity and cerebral connective tissue nevus. A mosaic somatic mutation of AKT1 gene is one of the pathogenic mutations for Proteus syndrome, and orthopedic surgery may be a good way to improve symptoms of the disease.

[A preliminary study of different methods of anesthesia for painless bronchoscopy].

Objective: This study aimed to explore a feasible method of anesthesia for painless bronchoscopy. Methods: A total of 120 patients receiving flexible bronchoscopy in Beijing Tiantan Hospital during the period from February, 8, 2018 to May, 4, 2018, were randomly divided into 3 groups, including group A (using lidocaine for local anesthesia), group B (using lidocaine + midazolam + fentanyl), and group C (using lidocaine + propofol + sufentanil). There were 41 patients in group A, 38 in group B and 41 in group C. The changes in systolic blood pressure, diastolic blood pressure, heart rate and pulse oxygen saturation(SpO(2)) in each group were recorded in different points of time. The safety of different methods of anesthesia was observed by recording vital signs and adverse events. Moreover, the visual analogue scale (VAS) was used to observe the patient's tolerance and satisfaction of the operation. Results: The intraoperative systolic blood pressure and diastolic blood pressure in group C were significantly lower than those in group A and B (P<0.05). Six cases in group C had hypotension, 3 of whom required vasoactive drugs. The differences of SpO(2) between the 3 groups showed no statistical significance (P>0.05), while patients in group C were prone to decrease in SpO(2). Eighteen patients in group C had hypoxemia during operation. But after treated with improving ventilation, the SpO(2) of those patients could be restored to normal. Compared with those in group C, patients in group A and group B showed significant discomfort, cough, and more pharyngeal pain (P<0.05). However, there were no significant differences in the degree of cough and pain between group A and group B (P>0.05). Most patients in group C had no uncomfortable sensation during the operation (P<0.05), and the willingness to re-examination was significantly higher than that in group A and group B (P<0.05). Conclusion: Propofol combined with sufentanil could achieve better painless effect, improve patient comfort and tolerance, and reduce intraoperative memory, but was prone to causing hypoxemia and hypotension. The decline of intraoperative SpO(2) could be corrected by establishing artificial airway, while the decrease of blood pressure could be corrected by applying vasoactive drugs, which were relatively safe.

[Effects on the respiration and nervous system of rat exposed to the thermobaric bomb simulated gas].

Objective: To investigate the effects of simulated-thermobaric explosive gas on the respiration and nervous system in rats. Methods: 70 of SPF SD rats were randomly divided into four thermobaric explosive gas groups, two restoration observation groups and control group from April to August in 2018. The exposure time of in four thermobaric explosive gas groups were 3.75, 7.5, 15.0 and 30 min, respectively. The restoration observation groups were designed to observe for 30 and 120 min after exposure thermobaric explosive gas 30 min. The bloods were collected and analyzed at the end of exposure and recovery observation. The endogenous carbon monoxide (CO) , nitric oxide (NO) , glutamic acid (GLU) , acetylcholinesterase (AchE) and dopamine (DA) were detected in brain tissues, respectively. Results: The blood gas index (pH, PCO(2), PO(2), COHb, O(2)Hb, MeHbt) and blood electrolytes (Na(+), K(+), Ca(2+) and Cl(-)) in exposure groups have significant differences with these in control (P<0.05) . The pH value decreased with the exposure time longer. However, it basically returned to normal level when terminating exposure for 120 min. The concentration of PCO(2), MeHb and CoHb increased first and then decreased with the exposure time extension. Conversely, The PO(2) and O(2)Hb decreased first and then increased with the exposure time longer. The concentration of endogenous CO, GLU, and AchE decreased and NO increased in exposure group 4 and the restoration observation group 1 compared with those in control (P<0.01) . In addition, there were pathological changes in lung and brain tissue of exposure group, such as inflammatory cell infiltration and edema. Conclusion: The blood gas index, electrolytes, neurotransmitter, histopathology of lung and brain were changed to various degrees by thermobaric bomb gas exposure. These findings would provide some beneficial support for evaluating the damage effect of thermobaric bomb gas on organisms.

The identification of up-regulated ebv-miR-BHRF1-2-5p targeting MALT1 and ebv-miR-BHRF1-3 in the circulation of patients with multiple sclerosis.

Epstein-Barr virus (EBV) is a well-documented aetiological factor for multiple sclerosis (MS). EBV encodes at least 44 microRNAs (miRNAs) that are readily detectable in the circulation of human. Previous studies have demonstrated that EBV-encoded miRNAs regulate host immune response and may serve as biomarkers for EBV-associated diseases. However, the roles of EBV miRNAs in MS are still unknown. To fill the gap, we conducted a comprehensive profiling of 44 mature EBV miRNAs in 30 relapsing-remitting MS (RRMS) patients at relapse and 30 matched healthy controls. Expression levels of ebv-miR-BHRF1-2-5p and ebv-miR-BHRF1-3 were elevated significantly in the circulation and correlated positively with the expanded disability status scale (EDSS) scores of MS patients. Receiver operating characteristic (ROC) analyses confirmed that the expression of these two miRNAs distinguished MS patients clearly from healthy controls. Luciferase assays revealed that ebv-miR-BHRF1-2-5p may directly target MALT1 (mucosa-associated lymphoid tissue lymphoma transport protein 1), a key regulator of immune homeostasis. In conclusion, we described the expression of EBV miRNAs in MS and preliminarily validated the potential target genes of significantly altered EBV miRNAs. The findings may pave the way for prospective study about the pathogenesis of MS.

TLR-Induced SMPD3 Defects Enhance Inflammatory Response of B Cell and Macrophage in the Pathogenesis of SLE.

B lymphocyte and macrophages may contribute to SLE pathogenesis through cytokine production after TLR stimulation. Emerging evidences suggested that defects of sphingolipid metabolism were responsible for SLE pathogenesis. However, it is not clear whether these defects exist in B cells and macrophages under SLE condition and whether TLR signalling pathway was related to the dysfunction of sphingolipid metabolism in SLE. Here, we demonstrated that the enzymes involved in the sphingolipid metabolism expressed abnormally in B cells from SLE patients and lupus-prone mice. Moreover, we found that TLR signalling induced the abnormal expression of sphingomyelin phosphodiesterase 3 (SMPD3), sphingosine-1-phosphate phosphatase 2 (SGPP2), ceramide kinase (CERK) and UDP glycosyltransferase 8 (UGT8), which were involved in sphingolipid metabolism. TLR signalling also induced the transportation of SMPD3 from Golgi apparatus. Furthermore, the dysfunction of SMPD3 enhanced TLR-induced inflammatory response of B cells and macrophages in turn. Thus, these findings provide an innovative direction and a new target for research and treatment of SLE.

Novel mutations in the SEC24D gene in Chinese families with autosomal recessive osteogenesis imperfecta.

We sought to characterize the phenotypes and identify the SEC24D gene mutations associated with Chinese families of osteogenesis imperfecta (OI). Using whole-exome sequencing, we discovered two novel compound SEC24D mutations of OI patients. Our study extended both the phenotypic and the genotype of the OI patients with SEC24D mutations. INTRODUCTION: To date, only three compound heterozygous mutations in the SEC24D gene have been found to cause recessively inherited forms of OI. We sought to characterize the phenotypes and to identify the SEC24D gene mutations associated with Chinese families with OI. METHODS: Using whole-exome sequencing in two probands, we identified two novel compound heterozygous mutations in SEC24D. In family 1, the proband was a 23-year-old male; he had recurrent fractures and dentinogenesis imperfecta. His anterior fontanel was not closed, and he showed facial dysmorphism. A computed tomography three-dimensional imaging of the cranium showed skull deformities associated with a broad ossification defect in the frontoapical area, a widened sagittal suture, and Wormian bones. In family 2, the proband was a 7-year-old boy, who also had recurrent fractures and dentinogenesis imperfecta. His anterior fontanel was not closed, and he did not have obvious facial dysmorphism. RESULTS: We identified one novel compound heterozygous missense substitution in the proband in family 1, including c.2723G>A (p. Cys908Tyr) and c.2842T>C (p. Ser948Pro). In the proband in family 2, we identified another novel compound heterozygous missense substitution, including c.938G>A (p. Arg313His) and c.875C>T (p. Pro292Leu). CONCLUSIONS: We discovered two novel compound SEC24D mutations of autosomal recessive OI patients. Our study extended both the phenotypic and the genotypic spectrum of the autosomal recessive OI patients with SEC24D mutations.

p-Cresyl sulfate is associated with carotid arteriosclerosis in hemodialysis patients and promotes atherogenesis in apoE-/- mice.

p-Cresyl sulfate (PCS) is a risk factor of cardiovascular disease in patients with chronic kidney disease. Here we tested whether serum PCS levels were related to the rate and evolution of carotid atherosclerosis in hemodialysis patients and identified a potential mechanism. A total of 200 hemodialysis patients were categorized as with or without carotid atherosclerotic plaque and followed for 5 years. Serum PCS levels were found to be higher in patients with than without carotid atherosclerotic plaque and positively correlated with increased total plaque area during follow-up. Multiple logistic regression and mixed effects model analyses showed that serum PCS levels were independently associated with the incidence and progression of carotid atherosclerotic plaque. PCS induced inflammatory factor and adhesion molecule expression in endothelial cells and macrophages. In addition, PCS triggered monocyte-endothelial cell interaction in vitro and in vivo through increased production of reactive oxygen species. Compared with controls, increase of PCS levels produced by gavage promoted atherogenesis in 5/6-nephrectomized apoE-/- mice; a process attenuated by NADPH oxidase inhibitors. Thus, increased serum PCS levels are associated with the occurrence and progression of carotid atherosclerosis in hemodialysis patients and promote atherogenesis through increased reactive oxygen species production.

Semen quality in adult male survivors 5 years after the 2008 Wenchuan earthquake.

The influence of the Wenchuan earthquake on semen quality of adult male survivors is unclear. We investigated the semen quality included 673 male survivors from the worse-affected counties in the earthquake between Aug 2008 and July 2013. Semen parameters including pH, volume, concentration, motility and morphology were measured according to the World Health Organization (WHO) criteria. Kruskal-Wallis analysis of variance was used to examine the statistical differences between years, and a logistic regression was used to analyse the impacts caused by earthquake on the changes of semen quality. We found the medians (5th and 95th) were 2.5 ml (0.6-5.5) for semen volume, 59.0 × 106  ml-1 [(13.0-133.0)] × 106  ml-1 for semen concentration, 46% (13-64%) for sperm progressive motility and 3.0% (0-17.5%) for normal morphology for adult male survivors. Semen concentration, the percentage of sperm progressive motility, total motility and sperm normal morphology were all decreased in the first 3 years, and the differences among years 1, 2 and 3 were significant except the percentage of sperm progressive motility (P < 0.05). The casualties and heavy housing damage caused by earthquake had a negative effect on semen quality. The main findings will provide further diagnosis and therapy basis of male fertility by data, for affected populations in the earthquake.

[The distribution characteristics of etiology of chronic cough in Lanzhou].

OBJECTIVE: To explore the distribution characteristics of etiology and clinical feature of chronic cough in Lanzhou. METHODS: Based on the guidelines of the diagnostic process of chronic cough in China, data of medical history and physical examinations were collected, and chest X-ray, pulmonary function plus airway hyperresponsiveness, induced sputum eosinophils, sinus X-ray or CT, 24 h esophageal pH monitoring, chest high-resolution CT and bronchoscopy were performed accordingly for outpatients with chronic cough. The cause of chronic cough was identified by the test results and treatment response. The results were compared with those reported previously in other areas of China. RESULTS: A total of 173 patients with completed data were collected, including 90 males and 83 females.The causes were as follows: 45 cases (26.01%) of cough variant asthma, 35 (20.23%) upper airway cough syndrome, 20 (11.56%) allergic cough, 17 (9.83%) chronic pharyngitis, 14 (8.09%) gastroesophageal reflux, 14 (8.09%)postinfectious, 13 (7.51%) eosinophilic bronchitis, 8 (4.62%) chronic bronchitis, 4 (2.31%) cough associated with ACEI, 3 (1.73%) bronchial tuberculosis, 2 (1.16%) pulmonary fibrosis and bronchiectasis repectively. The causes of the remaining 14 patients (8.09%)were unknown. The causes of chronic cough were identified in 159 patients (91.91%), of which 141 (88.68%) with a single cause and 18(11.32%)with more than 2 etiological factors.The percentage of cough variant asthma in our series was significantly higher than that reported in Guangzhou (13.6%, χ(2)=5.60, P=0.018, P<0.05), but lower than that reported in Shenyang (39.4%, χ(2)=7.91, P=0, 004, P<0.01). The percentage of allergic cough was higher than that reported in Beijing (3.3%, χ(2)=6.66, P=0.010, P<0.05), and that of eosinophilic bronchitis was lower than those reported in Guangzhou(22.4%, χ(2)=22.38, P=0.000, P<0.01) and Shenyang (12.5%, χ(2)=8.09, P=0.005, P<0.01). The percentage of esophageal reflux cough was lower than that reported in Beijing (20.3%, χ(2)=9.40, P=0.002, P<0.01) but higher than that reported in Shenyang (1.9%, χ(2)=3.98, P=0.036, P<0.05). CONCLUSION: In Lanzhou, cough variant asthma, upper airway cough syndrome, allergic cough, chronic pharyngitis and gastroesophageal reflux were the main causes of chronic cough, and the etiological distribution was different from Guangzhou, Beijing, Shenyang and other areas.