[Eosinophilic granulomatosis with polyangiitis: 30 cases report]

Objective: To improve the understanding of Eosinophilic granulomatosis with polyangiitis (EGPA). Methods: A total of 30 EGPA patients from the China-Japan Friendship Hospital between August 2005 and April 2017 were included, and a systematic retrospective study about clinical manifestations, laboratory findings, imaging features, pathology and so on was conducted. Results: There were 9 males and 21 females. Mean age was (44.5±13.9) years at diagnosis. Among these patients, 26 (86.7%) had asthma, duration was 45.0 (20.0, 78.7) months, and 15 (50.0%) had asthma as their first symptom. Rhinitis/nasosinusitis occurred in 27 (90.0%), skin lesions in 13 (43.3%), neuropathy in 10 (33.3%), heart disease in 8 (26.7%), renal involvement in 3 (10.0%) and gastro-intestinal manifestations in 3 (10.0%) of the patients. Peripheral blood eosinophil>10% accounted for 23/30 (76.7%). There were 3 patients (10.0%) who had positive anti-neutrophil antibody, and the pattern by immunofluorescence was mainly perinuclear. Migratory infiltrates often observed on the chest radiograph, and the main presentation was ground-glass opacity, amounting for 21/30 (70.0%). The pathological manifestations were extravascular eosinophilic tissue infiltration, necrotizing vasculitis, and extravascular granulomas, and the latter two of which were fewer. Conclusion: The manifestations of EGPA are individual, complex, with a lack of pathognomonic symptoms, and female predominated.

[Seasonal distribution of patient hospitalization due to asthma exacerbation in 7 geographic areas in China]

Objective: To understand the seasonal distribution of patient hospitalization due to asthma exacerbation in 7 geographic areas in China. Methods: This was a retrospective study which involved patients hospitalized for asthma exacerbation in 29 hospitals throughout 7 geographic areas in the mainland of China (northeast, north, central, east, south, northwest and southwest). The numbers of asthmatic patients and total inpatients of the respiratory department of each hospital were recorded. The monthly ratio of asthmatic patients to the total inpatients in every area was calculated and compared. Results: During the study period, 6 480 patients were admitted for asthma exacerbation, accounting for 3.14% of all the 206 135 patients admitted to the respiratory departments in the 29 hospitals. The ratio of asthmatic patients to total inpatients in the northeast area (5.61%) was highest, and the ratio in east area was lowest (1.97%). Statistical analysis showed that the difference among different areas was significant (P<0.000 1). In most areas, both the number and proportion of hospitalized asthmatic patients peaked in spring (February-April) and autumn (September-October). In the northeast area, east area and south area, the peaks in spring were more obvious, while in the north area and southwest area, the peaks in autumn were more obvious. In the northwest area the peaks occurred in winter (December-January) and summer (June-August), respectively. The differences in hospitalization due to asthma among different months were significant in the northeast, north, and southwest areas (P<0.005). Conclusion: The number of patients hospitalized for asthma exacerbation fluctuated with season in different areas in China. In most areas, more asthmatic patients were admitted to hospitals in spring and autumn.

[Seasonal characteristics of patients hospitalized for asthma exacerbation in China]

Objective: To study the seasonal characteristics of patients hospitalized for asthma exacerbation in China. Methods: This was a retrospective study which involved patients hospitalized for asthma exacerbation in 29 hospitals throughout mainland China during 2013-2014. The number of patients hospitalized for asthma exacerbation in each hospital was calculated, as well as the ratio of asthmatic patients to all the hospitalized patients. The analysis by month was conducted. The number and ratio of asthmatic patients in the northern and southern cities were calculated respectively. Results: During the study period, there were 6 480 patients hospitalized for asthma exacerbation, accounting for 3.14% (6 480/206 135) of all the hospitalized patients of the respiratory department in 29 hospitals. The analysis by month showed that the ratio of patients hospitalized for asthma exacerbation was highest in March (3.49%), then declined from April to June, then rose again from July, reaching a second peak at September (3.28%), and then declined again from October to December. The ratio of asthmatic patients in every month was higher in northern cities than in southern cities. Conclusions: The ratio of patients hospitalized for asthma exacerbation in China fluctuates with the changes of seasons, and March and September are the two peak months. Northern cities have a higher ratio of asthmatic patients than southern cities.

[Warning symptoms of asthma attack and asthma self-management: a national asthma control survey from China]

Objective: To investigate warning symptoms of asthma attack and evaluate asthma self-management status of asthma patients in urban China. Methods: A multi-center, cross-sectional, questionnaire-based survey was carried out from 30 general hospitals dispersed in 30 provinces of mainland China (except for Tibet) during Oct 2015 to May 2016. Information of frequency and warning symptoms of asthma attack, the time from warning symptoms to asthma attack, the impact of asthma attack and asthma self-management were collected from asthma patients of outpatient department. Results: Altogether 3 875 asthmatic outpatients were recruited. 78.1% (3 026/3 875) of the patients reported restriction of exercise and daily activities during asthma exacerbation. 82.5% (3 160/3 829) of the patients had warning symptoms before asthma attack, the most common warning symptoms were cough, chest tightness and shortness of breath. The median time from warning symptoms to asthma attack was 2 h, the mean time was 90 h. Only 4.4% (167/3 829) of the patients had definite confidence to control asthma when symptoms deteriorated. 76.7% (2 937/3 828) of the patients used medications to control asthma when asthma symptoms deteriorated. Medication choice: inhaled corticosteroid (ICS) + formoterol 45.8% (1 776/3 875), short-acting beta-agonist (SABA) 23.9% (927/3 875). Conclusions: Most asthma patients have warning symptoms before asthma attack, the most common symptoms are cough, chest tightness and shortness of breath. The proportion of patients conducting effective asthma self-management remains low.

[The level of asthma control in China from a national asthma control survey]

Objective: To assess the overall asthma control level in urban China. Methods: A multi-center, cross-sectional, questionnaire-based survey was carried out in 30 provinces in China (except Tibet). Asthmatic outpatients who met the inclusion criteria were recruited consecutively from 30 sub-centers from October 2015 to May 2016. Data of demographic characteristics, asthma control, asthma management, asthma exacerbations and self-management, and disease perception were collected by face-to-face interviews. Results: Totally 3 875 asthmatic outpatients were recruited. Asthma control level was assessed according to GINA 2015. The prevalence of asthma control was 28.5%(1 099/3 854). Among 10 cities, which were also involved in the asthma control survey in 2008, the level of asthma control improved from 28.7% in 2008 to 39.2%(533/1 361) in 2016. The rate of hospitalizations due to asthma exacerbations was 26.4%(1 017/3 858) and the rate of emergency visits was 22.4%(864/3 858). Among adult patients, 18.4%(568/3 092) of them had been absent from work while 63.6%(63/99) adolescent patients had been absent from school because of asthma attacks in the previous year. Conclusion: Although the level of asthma control in China is still far from ideal at present, the status has been improved in some cities. Poorly controlled asthma resulted in increase of hospitalizations, emergency department visits and work/school absences.

[A multi-center retrospective study of clinical characteristics and hospitalization costs of patients hospitalized for asthma exacerbation in China during 2013-2014]

Objective: To study the characteristics of patients hospitalized for asthma exacerbation in 29 teaching hospitals in China and to evaluate the hospitalization costs of these patients. Methods: This was a retrospective study and involved patients hospitalized for asthma exacerbation in 29 hospitals throughout China during 2013-2014. Information about the demographic features, conditions before the admission, the outcome, the complications, and the costs was collected using the pre-designed case report form. The influencing factors of the hospitalization costs were analyzed. Results: 3 240 asthmatic patients (1 369 males and 1 871 females) were included and data were analyzed. There were 41.5% (1 346/3 240) patients who had a history of previous hospitalization or emergency department visits during the last year. Only 28.0% (907/3 240) patients had used asthma-controlling medications regularly before the admission. Seventy-three(2.3%) patients were admitted to ICU and used mechanical ventilation. Mortality among these patients hospitalized for asthma exacerbation was 0.25% (8/3 240). The median hospitalization costs was 9 045(6 431, 13 035) RMB. The costs of medications, examinations and treatment accounted for 52.1%, 27.6%, and 9.6% respectively. The costs of asthma medications accounted for only 22.7% of the total medication costs, while the costs of antibiotics accounted for 44.0%. The patients who were admitted to ICU, used mechanical ventilation, complicated with pneumonia, or had a history of hospitalization or emergency department visits during the last year due to asthma exacerbations tended to cost more. Conclusion: In this study, we demonstrated that only a minority of the patients had used asthma controllers regularly before the admissions with exacerbations. The in-hospital mortality of asthma patients in this study was much lower than that reported in other countries. The average cost of hospitalization was much higher than the yearly cost of maintenance therapy. Medication was the predominant component of the total hospitalization costs, and the costs of antibiotics made up the major part of the total medication costs.

[A retrospective study of the treatment of patients hospitalized for asthma exacerbation in China]

Objective: To study the treatment of patients hospitalized for asthma exacerbation in China. Methods: This was a retrospective study and involved patients hospitalized for asthma exacerbation in 29 hospitals throughout China during Jan 2013 to Dec 2014. Information of the demographic features, the severity of the exacerbation, the medicine prescribed during the hospitalization and the use of mechanical ventilation were collected and analyzed. Results: During the study period, there were 3 240 patients hospitalized for asthma exacerbation, and 1 369(42.3%) of them were males 1 871(57.7%)were females. Patients of mild, moderate, severe, and life-threatening exacerbation counted for 41.7%, 37.8%, 19.2% and 1.0%, respectively of the total patients. Of all the patients, 72.6% used bronchodilators by nebulizer, 70.8% used inhaled corticosteroids by nebulizer, 60.5% used intravenous corticosteroids, 17.3% used oral corticosteroids, and 80.5% used antibiotics. The percentages of patients using systemic corticosteroids and antibiotics were higher in patients with more severe exacerbation. In patients with mild exacerbation, there were 74.9% and 52.2% who used antibiotics and systemic corticosteroids, respectively. A total of 73 patients (2.3%) used mechanical ventilation, and 62 of them used noninvasive ventilation, 16 used invasive ventilation, and 5 used both. Conclusions: Nebulizer therapy has been accepted as the main administration route of medicine in the treatment of asthma exacerbation. A large amount of patients used antibiotics and systemic corticosteroids during hospitalization, indicating there may be some overuse of these medicines.

[Evaluation of asthma disease perception from China national asthma control survey]

Objective: In order to evaluate disease perception of asthma patients in urban China and provide evidence for further specific patient education. Methods: A multi-center, cross-sectional, questionnaire-based survey was carried out in 30 general hospitals dispersed in 30 provinces of mainland China (except for Tibet) during Oct 2015 to May 2016. Information of disease perception [Question 1: the disease nature of asthma; Question 2: medication choice of first-line in chronic asthma; Question 3: the occasion of using short-acting aerosols of receptor agonists; Question 4: perception of asthma treatment goal; Question 5: reason for not using peak flow meter (PFM)] were collected from asthma patients of outpatient department. These results were compared with the same type of survey results from 2007-2008. Results: Altogether 3 875 asthmatic outpatients were recruited. 69.0% (2 660/3 857) of the patients had right perception on the disease nature of asthma, 60.2% (2 321/3 857) of the patients considered inhaled corticosteroids (ICS)/inhaled corticosteroids plus long-acting beta2-agonists (ICS+ LABA) as daily-used first-line medication for chronic asthma. 85.7% (3 277/3 823) of the patients had right perception on the condition of using short-acting beta2-agonists (SABA). 75.4% (2 761/3 661) of the patients had right perception on asthma treatment goal. Only 10.1% (388/3 837) of the patients used PFM. Of the reasons for not using PFM, 65.2% (2 518/3 860) of the patients chose doctors never introduced. Among the 10 cities, which were also involved in the asthma control survey in 2007-2008, 71.1% (968/1 361) of the patients had right perception on the disease nature of asthma, 61.6% (839/1 362) of the patients considered ICS/ICS+ LABA as daily-used first-line medication for chronic asthma. 88.7% (1 207/1 361) of the patients had right perception on the condition of using SABA. 74.5% (1 013/1 360) of the patients had right perception on asthma treatment goal. 17.9% (244/1 360) of the patients used PFM. Of the reasons for not using PFM, 76.2% (931/1 221) of the patients chose doctors never introduced. Compared to the survey conducted in 2007-2008, the perception on disease nature and medication choice as daily-used first-line medication for chronic asthma significantly improved, the perception on occasion of using SABA and asthma treatment goal was comparable, while the rate of PFM usage showed no significant improvement. In reasons of not using PFM, doctors never introduced ranked the first. Conclusions: Compared to the similar survey conducted in 2007-2008, the overall status of disease perception of asthma patients has been improved in urban China, while the rate of PFM usage showed no significant improvement. Asthma education on asthma and asthma self-management should be further pushed forward.

[A retrospective study of the mortality and death-related risk factors of patients hospitalized for asthma exacerbation in Chinese urban areas]

Objective: To study the mortality and death-related risk factors of patients hospitalized for asthma exacerbation in Chinese urban areas. Methods: A retrospective study was carried out in 29 hospitals of 29 provinces throughout mainland China. Patients hospitalized for asthma exacerbation during 2013-2014 in each hospital were included. For each patient, information about demography, admission time, comorbidities, severity of diseases, intense care unit (ICU) admission, use of mechanical ventilation and the outcome was obtained. The mortality of patients hospitalized for asthma exacerbation was calculated, and the basic information and causes of death of the patients who died were summarized. The death-related risk factors and numbers of comorbidities were compared between the patients who survived and those who died during hospitalization. Results: A total of 3 240 patients (median age 57.0) were included and among them 8 patients (median age 68.5) died. The mortality of patients hospitalized for asthma exacerbation was 0.25%. All the patients who died were admitted during the winter and spring. One patient died of acute myocardial infarction, one of cardiac shock, one of tension pneumothorax, one of sudden death, one of respiratory failure and three of unknown causes. The average number of comorbidities of patients who died was 1.10, larger than that of patients who survived (0.83) (P>0.05). More patients had diabetes, coronary artery diseases and hypertension as comorbidities in the patients who died (2/8) than those who survived[7.6% (246/3 232), 7.6% (246/3 232), 22.6% (731/3 232), respectively](all P>0.05). Conclusions: The in-hospital mortality of patients hospitalized for asthma exacerbation of China in this study is low. The patients who died are much older, and with more comorbidities, and a higher percentage of comorbidities such as diabetes, coronary artery diseases, and hypertension.

[A multi-center study for the association between the perception and control of disease among asthmatic patients in Chinese urban areas]

Objective: To investigate the current perception of disease among asthmatic patients in Chinese urban areas, and to address its association with asthma control. Methods: This was a nationwide, multi-center, cross-sectional study covering 30 third-level, grade A hospitals in 30 provinces, municipalities and autonomous regions (not including Tibet) across Chinese mainland. The survey was carried out from October 2015 to May 2016. Asthmatic outpatients were selected to receive face-to-face questionnaire survey on asthma control including Asthma Control Test (ACT) score, classification of asthma control level[according to the Global Initiative for Asthma (GINA) 2015 classification system, as assessed by the physician completing the survey], perception of asthma (including question 1: nature of asthma as a disease; question 2: selection of first-line therapeutic agents to be regularly used daily for asthma; question 3: appropriate timing of the use of short-acting aerosols of β(2) receptor agonists; and question 4: therapeutic goals for asthma). Results: A total of 3 875 asthmatic outpatients were included; among them, 69.0% (2 660/3 857) were aware that asthma is "an airway inflammatory disorder resulting from the combined effects of heredity and environment" ; 60.2% (2 321/3 857) considered "inhaled glucocorticoids or their compound preparations" to be the first-line therapeutic agents to be regularly used daily for patients with persistent chronic asthma; 85.7% (3 277/3 823) considered it appropriate to use short-acting aerosols of β(2) receptor agonists "as needed in the event of disease aggravation or acute exacerbation" ; and 75.4% (2 761/3 661) were aware that asthma "can be adequately or completely controlled in the long term" . The ACT score[20 (16, 23) vs 19 (16, 22) points; Z=-3.928, P<0.001]and asthma control rate (29.92% vs 25.31%; χ(2)=8.616, P=0.003) were significantly higher, and the rate of uncontrolled asthma (19.92% vs 23.48%; χ(2)=6.267, P=0.012) was significantly lower among the 2 660 (69.0%) patients correctly answering question 1 than among the 1 197 (31.0%) patients giving incorrect answer. The ACT score[21 (17, 23) vs 19 (15, 22) points; Z=-9.190, P<0.001] and asthma control rate (32.66% vs 22.20%; χ(2)=49.614, P<0.001) were significantly higher, and the rate of uncontrolled asthma (18.40% vs 25.00%; χ(2)=24.267, P<0.001) was significantly lower among the 2 321 (60.2%) patient correctly answering question 2 than among the 1 536 (39.8%) patients giving incorrect answer. Conclusions: Compared to previous surveys, there has been improved perception of disease among asthmatic patients in Chinese urban areas. Correct perception of disease is favorable for improving asthma control level.

Partner-Drug Resistance and Population Substructuring of Artemisinin-Resistant Plasmodium falciparum in Cambodia

Plasmodium falciparum in western Cambodia has developed resistance to artemisinin and its partner drugs, causing frequent treatment failure. Understanding this evolution can inform the deployment of new therapies. We investigated the genetic architecture of 78 falciparum isolates using whole-genome sequencing, correlating results to in vivo and ex vivo drug resistance and exploring the relationship between population structure, demographic history, and partner drug resistance. Principle component analysis, network analysis and demographic inference identified a diverse central population with three clusters of clonally expanding parasite populations, each associated with specific K13 artemisinin resistance alleles and partner drug resistance profiles which were consistent with the sequential deployment of artemisinin combination therapies in the region. One cluster displayed ex vivo piperaquine resistance and mefloquine sensitivity with a high rate of in vivo failure of dihydroartemisinin-piperaquine. Another cluster displayed ex vivo mefloquine resistance and piperaquine sensitivity with high in vivo efficacy of dihydroartemisinin-piperaquine. The final cluster was clonal and displayed intermediate sensitivity to both drugs. Variations in recently described piperaquine resistance markers did not explain the difference in mean IC₉₀ or clinical failures between the high and intermediate piperaquine resistance groups, suggesting additional loci may be involved in resistance. The results highlight an important role for partner drug resistance in shaping the P. falciparum genetic landscape in Southeast Asia and suggest that further work is needed to evaluate for other mutations that drive piperaquine resistance.

Association of a Novel Mutation in the Plasmodium falciparum Chloroquine Resistance Transporter With Decreased Piperaquine Sensitivity

Background

Amplified copy number in the plasmepsin II/III genes within Plasmodium falciparum has been associated with decreased sensitivity to piperaquine. To examine this association and test whether additional loci might also contribute, we performed a genome-wide association study of ex vivo P. falciparum susceptibility to piperaquine.

Methods

Plasmodium falciparum DNA from 183 samples collected primarily from Cambodia was genotyped at 33716 genome-wide single nucleotide polymorphisms (SNPs). Linear mixed models and random forests were used to estimate associations between parasite genotypes and piperaquine susceptibility. Candidate polymorphisms were evaluated for their association with dihydroartemisinin-piperaquine treatment outcomes in an independent dataset.

Results

Single nucleotide polymorphisms on multiple chromosomes were associated with piperaquine 90% inhibitory concentrations (IC90) in a genome-wide analysis. Fine-mapping of genomic regions implicated in genome-wide analyses identified multiple SNPs in linkage disequilibrium with each other that were significantly associated with piperaquine IC90, including a novel mutation within the gene encoding the P. falciparum chloroquine resistance transporter, PfCRT. This mutation (F145I) was associated with dihydroartemisinin-piperaquine treatment failure after adjusting for the presence of amplified plasmepsin II/III, which was also associated with decreased piperaquine sensitivity.

Conclusions

Our data suggest that, in addition to plasmepsin II/III copy number, other loci, including pfcrt, may also be involved in piperaquine resistance.

[The relationship between smoking status and epidermiology of asthma in people aged over 14 years in China]

Objective: To study the relationship between bronchial asthma and smoking status in Chinese people. Methods: Asthma epidemiological survey and stratified-cluster-random method survey were performed in residents over 14 years in 8 provinces (cities) of China from February 2010 to August 2012. Asthma was diagnosed based upon case history, clinical signs and lung function test. Smoking status was investigated by questionnaire. Results: Sampling population was 180 099 and 164 215 were valid. A total of 2 034 subjects were diagnosed as asthma including 79 692 men and 84 523 women. The overall prevalence rate of asthma was 1.24% (2 034/164 215). Smokers were 23.8% (39 137/164 215) in the whole population. Smokers were 34.5% (702/2 034) in asthmatic patients, compared with 23.7% (38 435/162 181) in no-asthmatic population. The incidence of asthma was 1.79% and 1.06% in smokers and non-smokers respectively (P<0.001), suggesting that OR of smoking was 1.70 (95% CI 1.55-1.86, P<0.001). According to asthma control test (ACT) score, the level of asthma control in non smoking group was higher than that in smoking group(43.2% vs 35.3%). The times of hospitalization due to acute exacerbations(0.51 vs 0.41 events/person/year), total hospitalization rate(27.35% vs 20.12%), annual emergency room visits (0.80 vs 0.60 events/person/year) and emergency room visit rate (31.77% vs 24.47%) were all much higher in smoking asthmatic patients than those in non smoking asthmatic patients, indicating that the level of asthma control in smoking patients was significantly worse than in non smoking patients. Conclusions: The smoking rate in Chinese people over 14 years is still high. The prevalence rate of asthma in smokers is significantly higher than that of non-smokers. The level of asthma control in smokers is significantly worse than that in non smokers.

[Analysis of short-term respiratory adverse events in 183 bronchial thermoplasty procedures]

Objective: To analyze the short-term (3 weeks) adverse respiratory events after bronchial thermoplasty(BT) in patients with severe asthma. Methods: The China-Japan Friendship Hospital recruited 62 patients with severe asthma for BT treatment from March 2014 to July 2016, with a total of 183 BT procedures. The data of adverse respiratory events within 3 weeks after procedure were collected to analyze the factors that might potentially influence the occurrence of adverse events. Results: Forty-three patients (69.4%) experienced adverse respiratory events within 3 weeks after treatment. Totally 153 adverse respiratory events occurred after 87 procedures(47.5%). The main adverse events were cough (15 events, 8.20%), sputum production (37 events, 20.22%), temporary PEF reduction (37 events, 20.22%), chest distress (12 events, 6.56%), blood in sputum (11 events, 6.01%), asthma exacerbation (10 events, 5.46%), and pneumonia(6 events, 3.28%). Most events were relieved or resolved with standard therapy in 1 week. No severe adverse events including tracheal intubation, malignant arrhythmias or death occurred within 3 weeks after procedure. The baseline eosinophil percentage in induced sputum and blood, operation times, and preoperative FEV(1) (% predicted) might influence the occurrence of adverse events after treatment. Patients with preoperative FEV(1) (% predicted) ≥60% had lower risk of adverse events. Conclusion: BT showed a good security profile in treating patients with severe asthma within 3 weeks after procedure.

[Chinese expert consensus for non-antiinfective effects and clinical use of macrolides]

Important/potential value of macrolides has been proved in the management of chronic respiratory diseases by increasing basic and clinical trials.Through three face-to-face discussions, 10 experts examined important data and drafted this consensus related to macrolides: (1) mechanism of non-antiinfective effects; (2) clinical use in chronic respiratory diseases; (3) cautions of long-term use.The mechanism out of non-antiinfective effects includes anti-inflammatory effect, modifying airway secretion, immune-regulation related to antibacterial effect, corticoid saving effect and anti-viral effect.The efficacy of long-term use of low-dose macrolides is definitely confirmed in diffuse panbronchiolitis, chronic rhinosinusitis. It is considerably used in bronchiectasia, cystic fibrosis, severe asthma and chronic obstructive pulmonary disease. Further studies should be conducted in cryptogenic organizing pneumonia and respiratory viral infection. It should be paid attention to its possible adverse effects (including drug interactions, cardiac toxicity, ototoxicity and disturbance of intestinal flora) and drug resistance in long-term use.A Chinese consensus for non-antiinfective effects and clinical use of macrolides is developed for the first time, which aims to expand their rational use and the further research.

[A cross-section study of severe asthma in eight provinces of China]

Objective: To analyze the prevalence of severe asthmain China. Methods: The epidemiological data was collected from 2 034 asthmatics who were diagnosed in the last epidemiological survey from 2009 to 2010 in 8 provinces. Results: According to the questionnaire survey, among the 2 034 patients, the previously diagnosed patients accounted for 72.47% (1 474/2 034) and the percentage of newly-diagnosed patients was 27.53% (560/2 034). In those 1 474 previously diagnosed asthmatics, 122 (8.28%) were classified into severe asthma, while 6.00% (122/2 034) of all asthmatics and 0.07% (122/164 215) of total respondents presented as severe cases. Statistically, there was no difference in the prevalence of severe patients between men and women. The morbidity rate of severe asthma was the lowest in the 21-30 year old group and the highest in 61-70 year old group (0.85% and 8.31% respectively). The difference among ages was statistically significant (χ²=18.791, P=0.005). In addition, the prevalence rates of severe asthma were also significantly diverged among patients with different education background(χ²=24.639, P<0.000 1). A negative relation was found between education level and the proportion of severe cases. Moreover, the morbidity of severe asthma in smoking patients and non-smoking patients were significantly different as well (χ²=7.447, P<0.05). Compared with asthma patients who do not smoke, smokers were more likely to suffer severe asthma (OR=1.663, 95% CI 1.150-2.404). Conclusions: The prevalence rate of severe asthma in China is similar to that in other countries.Elderly patients have higher risk of severe asthma. Smoking is considered as a risk factor for severe asthma.

Longitudinal Pooled Deep Sequencing of the Plasmodium vivax K12 Kelch Gene in Cambodia Reveals a Lack of Selection by Artemisinin

The emergence of artemisinin resistance among Plasmodium falciparum in the Greater Mekong subregion threatens malaria control interventions and is associated with multiple unique mutations in K13 (PF3D7_1343700). The aim of this study was to survey Cambodian Plasmodium vivax for mutations in the K13 ortholog (K12, PVX_083080) that might similarly confer artemisinin resistance. Extracted DNA from Cambodian isolates collected between 2009 and 2012 was pooled by province and year and submitted for next-generation sequencing. Single-nucleotide polymorphisms (SNPs) were identified using a pile-up approach that detected minority SNPs. Among the 14 pools, we found six unique SNPs, including three nonsynonymous SNPs, across six codons in K12 However, none of the SNPs were orthologous to artemisinin resistance-conferring mutations in PF3D7_1343700, and nonsynonymous changes did not persist through time within populations. These results suggest a lack of selection in the P. vivax population in Cambodia due to artemisinin drug pressure.

[Distribution characteristics of serotypes of invasive pneumococcal disease in Chinese mainland children]

OBJECTIVE

To systematically estimate the regional distributions of invasive pneumococcal disease (IPD)'s serotypes in children of Chinese mainland.

METHODS

The literatures which described at least 20 strains of streptococcus pneumonia samples isolated from children with IPD in Chinese mainland were included in this study. Finally, 39 literatures met the inclusion criteria and were reviewed in this study. The average frequency of each serotype of streptococcus pneumonia was calculated and the uncertainty of each serotype range was described by 95% CI.

RESULTS

This study analyzed a total of 7 391 strains of streptococcus pneumoniae samples which mainly came from north China, east China, central China, south China and southwest regions of China. The results showed that the most common streptococcus pneumonia serotype causing IPD was 19F[30.05% (28.16%-31.98%)], and the second serotype was 23F[12.16% (10.00%-14.28%)], and the others were 19A[9.19% (7.01%-11.37%)], 6B[7.30% (5.09%-9.50%)], 14[7.02% (4.82%-9.23%)], 6A[6.08% (3.87%-8.30%)]and 15B[6.53% (2.88%-7.34%)].

CONCLUSION

The most common streptococcus pneumoniae serotype is 19F, 23F, 19A, 6B, 14, 6A and 15B in Chinese Mainland.

[Effects of artesunate on cigarette smoke-induced lung oxidative damage in mice and the expression of Nrf2 and the possible mechanism]

OBJECTIVE

To explore the effects of artesunate on cigarette smoke-induced lung oxidative damage in mice and the expression of Nuclear factor-E2-related factor 2 (Nrf2).

METHODS

In vivo: A total of 40 female specific pathogen free BALB/c mice were divided randomly into four groups: normal group, cigarette smoke group, vehicle group and artesunate group. The latter three groups were exposed on cigarette smoke for 40 days. Vehicle (5% NaHCO3 containing 5% dimethyl sulfoxide, 0.1 ml of each mice) or artesunate (30 mg/kg, dissolved in the 0.1 ml vehicle) was given by intraperitoneal injections before each passive smoking of the vehicle or artesunate group. Saline of 0.1ml was given to the normal and cigarette smoke groups as negative controls. Cells in bronchoalveolar lavage fluid (BALF) were collected and analyzed by absolute different cell counts. Interleukin (IL)-8 levels in BALF and 3-nitrotyrosine (NT) levels in lung tissue were tested by emzyme linked immunosorbent assay (ELISA). Malondialdehyde levels in serum, total superoxide dismutase (SOD) activity and total glutathione peroxidase (GPx) activity in lung tissue were detected. The pathological changes of lung tissues were observed by HE staining. And the expression levels of Nrf2 were measured by Westernblotting. In vitro: 16HBE cells were cultured and transfected with Nrf2 siRNA. Cigarette smoke extract (CSE) were used to stimulate the secretion of IL-8 in cells. Cells were divided into five groups: blank group, non-transfected non-artesunate group, non-transfected artesunate group, transfected non-artesunate group and transfected artesunate group. The latter four groups were incubated with CSE, and non-transfected artesunate and transfected artesunate groups were intervened with artesunate (30 μmol/L) before CSE incubation. The IL-8 levels of each group were measured using ELISA kit.

RESULTS

In vivo: The total cell counts of BALF in artesunate group were significantly lower than the vehicle group [21.00(2.50)×10(4)/ml vs 35.50(2.50)×10(4)/ml, P<0.001], especially neutrophil counts [6.00(5.12)×10(4)/ml vs 13.60(5.25)×10(4)/ml, P<0.001]. The IL-8 levels in BALF, malondialdehyde levels in serum, 3-NT levels and total SOD activity in lung tissue of artesunate group were all drastically lower than those in the vehicle group [(508±55) vs (912±68) ng/L, (38.2±8.8) vs (48.7±10.6) μmol/L, (28.5±5.8) vs (50.0±9.7) μg/L and (11.8±1.8) vs (18.0±5.3) U/mg protein, respectively, all P<0.05]. No significant difference of total GPx activity existed in these four groups. And the expression level of Nrf2 in artesunate group significantly increased than that in vehicle group (P=0.008). In vitro: The IL-8 level of the non-transfected artesunate group was significantly lower than the non-transfected non-artesunate group [(352±26) vs (765±22) ng/L, P<0.001], while the IL-8 levels between the transfected artesunate and transfected non-artesunate groups had no significant difference.

CONCLUSION

Arteunate attenuates cigarette smoke-induced lung oxidative damage in mice and increases the expression level of Nrf2, and its effects might be mediated by the actions of nuclear Nrf2.

Microscopic Plasmodium falciparum Gametocytemia and Infectivity to Mosquitoes in Cambodia

Although gametocytes are essential for malaria transmission, in Africa many falciparum-infected persons without smear-detectable gametocytes still infect mosquitoes. To see whether the same is true in Southeast Asia, we determined the infectiousness of 119 falciparum-infected Cambodian adults to Anopheles dirus mosquitoes by membrane feeding. Just 5.9% of subjects infected mosquitoes. The 8.4% of patients with smear-detectable gametocytes were >20 times more likely to infect mosquitoes than those without and were the source of 96% of all mosquito infections. In low-transmission settings, targeting transmission-blocking interventions to those with microscopic gametocytemia may have an outsized effect on malaria control and elimination.

Attenuation of Plasmodium falciparum in vitro drug resistance phenotype following culture adaptation compared to fresh clinical isolates in Cambodia

Background

There is currently no standardized approach for assessing in vitro anti-malarial drug susceptibility. Potential alterations in drug susceptibility results between fresh immediate ex vivo (IEV) and cryopreserved culture-adapted (CCA) Plasmodium falciparum isolates, as well as changes in parasite genotype during culture adaptation were investigated.

Methods

The 50 % inhibitory concentration (IC₅₀) of 12 P. falciparum isolates from Cambodia against a panel of commonly used drugs were compared using both IEV and CCA. Results were compared using both histidine-rich protein-2 ELISA (HRP-2) and SYBR-Green I fluorescence methods. Molecular genotyping and amplicon deep sequencing were also used to compare multiplicity of infection and genetic polymophisms in fresh versus culture-adapted isolates.

Results

IC₅₀ for culture-adapted specimens were significantly lower compared to the original fresh isolates for both HRP-2 and SYBR-Green I assays, with greater than a 50 % decline for the majority of drug-assay combinations. There were correlations between IC₅₀s from IEV and CCA for most drugs assays. Infections were nearly all monoclonal, with little or no change in merozoite surface protein 1 (MSP1), MSP2, glutamate-rich protein (GLURP) or apical membrane antigen 1 (AMA1) polymorphisms, nor differences in P. falciparum multidrug resistance 1 gene (PfMDR1) copy number or single nucleotide polymorphisms following culture adaptation.

Conclusions

The overall IC₅₀ reduction combined with the correlation between fresh isolates and culture-adapted drug susceptibility assays suggests the utility of both approaches, as long as there is consistency of method, and remaining mindful of possible attenuation of resistance phenotype occurring in culture. Further study should be done in higher transmission settings where polyclonal infections are prevalent.

Electronic supplementary material

The online version of this article (doi:10.1186/s12936-015-1021-8) contains supplementary material, which is available to authorized users.