Over the past decades, asthma and allergic diseases, such as allergic rhinitis and eczema, have become increasingly common, but the reason for this increased prevalence is still unclear. It has become apparent that genetic variation alone is not sufficient to account for the observed changes; rather, the changing environment, together with alterations in lifestyle and eating habits, are likely to have driven the increase in prevalence, and in some cases, severity of disease. This is particularly highlighted by recent awareness of, and concern about, the exposure to ubiquitous environmental pollutants, including chemicals with oxidant-generating capacities, and their impact on the human respiratory and immune systems. Indeed, several epidemiological studies have identified a variety of risk factors, including ambient pollutant gases and airborne particles, for the prevalence and the exacerbation of allergic diseases. However, the responsible pollutants remain unclear and the causal relationship has not been established. Recent studies of cellular and animal models have suggested several plausible mechanisms, with the most consistent observation being the direct effects of particle components on the generation of reactive oxygen species (ROS) and the resultant oxidative stress and inflammatory responses. This review attempts to highlight the experimental findings, with particular emphasis on several major mechanistic events initiated by exposure to particulate matters (PMs) in the exposure-disease relationship.
Air pollution; asthma; allergic disease; particulate matter (PM); polycyclic aromatic hydrocarbon (PAH); transition metal; aryl hydrocarbon receptor (AhR)
Outdoor air pollution is one of the leading contributors to adverse respiratory health outcomes in urban areas around the world. Children are highly sensitive to the adverse effects of air pollution due to their rapidly growing lungs, incomplete immune and metabolic functions, patterns of ventilation and high levels of outdoor activity. The Children’s Health Study (CHS) is a continuing series of longitudinal studies that first began in 1993 and has focused on demonstrating the chronic impacts of air pollution on respiratory illnesses from early childhood through adolescence. A large body of evidence from the CHS has documented that exposures to both regional ambient air and traffic-related pollutants are associated with increased asthma prevalence, new-onset asthma, risk of bronchitis and wheezing, deficits of lung function growth, and airway inflammation. These associations may be modulated by key genes involved in oxidative-nitrosative stress pathways via gene-environment interactions. Despite successful efforts to reduce pollution over the past 40 years, air pollution at the current levels still brings many challenges to public health. To further ameliorate adverse health effects attributable to air pollution, many more toxic pollutants may require regulation and control of motor vehicle emissions and other combustion sources may need to be strengthened. Individual interventions based on personal susceptibility may be needed to protect children’s health while control measures are being implemented.
Air pollution; traffic pollution; asthma; genetic susceptibility; respiratory disease
The association between ambient air pollution (AAP) exposure and lung cancer risk has been investigated in prospective studies and the results are generally consistent, indicating that long-term exposure to air pollution can cause lung cancer. Biomarkers can enhance research on the health effects of air pollution by improving exposure assessment, increasing the understanding of mechanisms, and enabling the investigation of individual susceptibility. In this review, we assess DNA adducts as biomarkers of exposure to AAP and early biological effect, and DNA methylation as biomarker of early biological change and discuss critical issues arising from their incorporation in AAP health impact evaluations, such as confounding, individual susceptibilities, timing, intensity and duration of exposure, and investigated tissue. DNA adducts and DNA methylation are treated as paradigms. However, the lessons, learned from their use in the examination of AAP carcinogenicity, can be applied to investigations of other biomarkers involved in AAP carcinogenicity.
Carcinogenicity; biomarkers; ambient air pollution (AAP); lung cancer; DNA adducts; DNA methylation
In many areas of the world, concentrations of ambient air pollutants exceed levels associated with increased risk of acute and chronic health problems. While effective policies to reduce emissions at their sources are clearly preferable, some evidence supports the effectiveness of individual actions to reduce exposure and health risks. Personal exposure to ambient air pollution can be reduced on high air pollution days by staying indoors, reducing outdoor air infiltration to indoors, cleaning indoor air with air filters, and limiting physical exertion, especially outdoors and near air pollution sources. Limited evidence suggests that the use of respirators may be effective in some circumstances. Awareness of air pollution levels is facilitated by a growing number of public air quality alert systems. Avoiding exposure to air pollutants is especially important for susceptible individuals with chronic cardiovascular or pulmonary disease, children, and the elderly. Research on mechanisms underlying the adverse health effects of air pollution have suggested potential pharmaceutical or chemopreventive interventions, such as antioxidant or antithrombotic agents, but in the absence of data on health outcomes, no sound recommendations can be made for primary prevention. Health care providers and their patients should carefully consider individual circumstances related to outdoor and indoor air pollutant exposure levels and susceptibility to those air pollutants when deciding on a course of action to reduce personal exposure and health risks from ambient air pollutants. Careful consideration is especially warranted when interventions may have unintended negative consequences, such as when efforts to avoid exposure to air pollutants lead to reduced physical activity or when there is evidence that dietary supplements, such as antioxidants, have potential adverse health effects. These potential complications of partially effective personal interventions to reduce exposure or risk highlight the primary importance of reducing emissions of air pollutants at their sources.
Air pollution; prevention; cardiovascular disease; pulmonary disease; behavior
Air pollution in many Chinese cities has been so severe in recent years that a special terminology, the “Chinese haze”, was created to describe China’s air quality problem. Historically, the problem of Chinese haze has developed several decades after Western high-income countries have significantly improved their air quality from the smog-laden days in the early- and mid-20th century. Hence it is important to provide a global and historical perspective to help China combat the current air pollution problems. In this regard, this article addresses the followings specific questions: (I) What is the Chinese haze in comparison with the sulfurous (London-type) smog and the photochemical (Los Angeles-type) smog? (II) How does Chinese haze fit into the current trend of global air pollution transition? (III) What are the major mitigation measures that have improved air quality in Western countries? and (IV) What specific recommendations for China can be derived from lessons and experiences from Western countries?
Air pollution; emissions; health effects; clean air legislation
With fewer newborns and people living longer, older people are making up an increasing fraction of the total population. Epidemiological evidence shows that older-age-related health problems affect a wide and expanding proportion of the world population. One of the major epidemiological trends of this century is the rise of chronic diseases that affect more elderly than younger people. A total of 3.7 million premature deaths worldwide in 2012 are attributable to outdoor air pollution; the susceptibility to adverse effects of air pollution is expected to differ widely between people and within the same person, and also over time. Frailty history, a measure of multi-system decline, modifies cumulative associations between air pollution and lung function. Moreover, pre-existing diseases may determine susceptibility. In the elderly, due to comorbidity, exposure to air pollutants may even be fatal. Rapid and not-well-planned urbanization is associated with high level of ambient air pollution, mainly caused by vehicular exhausts. In general, there is sufficient evidence of the adverse effects related to short-term exposure, while fewer studies have addressed the longer-term health effects. Increased pollution exposures have been associated with increased mortality, hospital admissions/emergency-room visits, mainly due to exacerbations of chronic diseases or to respiratory tract infections (e.g., pneumonia). These effects may also be modulated by ambient temperature and many studies show that the elderly are mostly vulnerable to heat waves. The association between heat and mortality in the elderly is well-documented, while less is known regarding the associations with hospital admissions. Chronic exposure to elevated levels of air pollution has been related to the incidence of chronic obstructive pulmonary disease (COPD), chronic bronchitis (CB), asthma, and emphysema. There is also growing evidence suggesting adverse effects on lung function related to long-term exposure to ambient air pollution. Few studies have assessed long-term mortality in the elderly. It is still unclear what are the pollutants most damaging to the health of the elderly. It seems that elderly subjects are more vulnerable to particulate matter (PM) than to other pollutants, with particular effect on daily cardio-respiratory mortality and acute hospital admissions. Not many studies have targeted elderly people specifically, as well as specific respiratory morbidity. Most data have shown higher risks in the elderly compared to the rest of the population. Future epidemiological cohort studies need to keep investigating the health effects of air pollutants (mainly cardiopulmonary diseases) on the elderly.
Outdoor air pollution; elderly people; frailty elderly; respiratory disease; environmental exposure
With the levels of outdoor air pollution from industrial and motor vehicle emissions rising rapidly in the fastly-industrializing countries of South East Asia, the prevalence of asthma and allergic diseases has also been increasing to match those in the West. Epidemiological and experimental exposure studies indicate a harmful impact of outdoor air pollution from vehicles and factories both on the development of allergic diseases and asthma and the increase in asthma symptoms and exacerbations. The level of outdoor pollution in Asia is much higher and more diverse than those encountered in Western countries. This may increase the impact of outdoor pollution on health, particularly lung health in Asia. This review discusses the constituents of air pollution in Asia with a special focus on studies in mainland China and Taiwan where the levels of pollution have reached high levels and where such high levels particularly in winter can cause a thick haze that reduces visibility. The onus remains on regulatory and public health authorities to curb the sources of pollution so that the health effects on the population particularly those with lung and cardiovascular diseases and with increased susceptibility can be mitigated.
Allergy; environmental air pollution; particulate matter (PM); ozone (O3); nitrogen dioxide (NO2); asthma
Recently, many researchers paid more attentions to the association between air pollution and chronic obstructive pulmonary disease (COPD). Haze, a severe form of outdoor air pollution, affected most parts of northern and eastern China in the past winter. In China, studies have been performed to evaluate the impact of outdoor air pollution and biomass smoke exposure on COPD; and most studies have focused on the role of air pollution in acutely triggering symptoms and exacerbations. Few studies have examined the role of air pollution in inducing pathophysiological changes that characterise COPD. Evidence showed that outdoor air pollution affects lung function in both children and adults and triggers exacerbations of COPD symptoms. Hence outdoor air pollution may be considered a risk factor for COPD mortality. However, evidence to date has been suggestive (not conclusive) that chronic exposure to outdoor air pollution increases the prevalence and incidence of COPD. Cross-sectional studies showed biomass smoke exposure is a risk factor for COPD. A long-term retrospective study and a long-term prospective cohort study showed that biomass smoke exposure reductions were associated with a reduced decline in forced expiratory volume in 1 second (FEV1) and with a decreased risk of COPD. To fully understand the effect of air pollution on COPD, we recommend future studies with longer follow-up periods, more standardized definitions of COPD and more refined and source-specific exposure assessments.
Biomass smoke; air pollution; haze; chronic obstructive pulmonary disease (COPD)
A 53-year-old male smoker was referred to our hospital with an enlarged lesion in the right upper lung. Computed tomography (CT) showed a 1.5 cm solid lesion with pleural indentation in the right upper lobe adjacent to the oblique fissure. The preoperative clinical diagnosis was stage I primary lung cancer. Uniportal video-assisted thoracoscopic surgery (VATS) right upper lobectomy in a semiprone position was performed in this case. Frozen section examination confirmed the diagnosis of lung adenocarcinoma, and systematic lymphadenectomy was then performed. A chest tube was placed at the posterior part of the incision through the dorsal thoracic cavity to the apex. The postoperative pathologic diagnosis was T2aN0M0 adenocarcinoma.
Video-assisted thoracoscopic surgery (VATS); uniportal; lobectomy; lung cancer; lymphadenectomy
The objective of the present study is to analyze the epidemiological profile of patients with abnormal valvular structure and function and highlight the etiological spectrum and management of valvular heart disease (VHD) in a single cardiovascular center of Southern China in five years.
The retrospective study included 19,428 consecutive patients (9,441 men and 9,987 women with a mean age of 52.03±20.50 years) with abnormal valvular structure and function who were screened by transthoracic echocardiography (TTE) or transesophageal echocardiography (TEE) at the in-patient department of Guangdong General Hospital from January 2009 to December 2013. Data on baseline characteristics, potential etiology, treatment strategies and discharge outcomes were collected from electronic medical records.
There were 13,549 (69.7%) patients with relatively definite etiology for VHD. VHD was rheumatic in 7,197 (37.0%) patients, congenital in 2,697 (13.9%), degenerative in 2,241 (11.5%), ischemic in 2,460 (12.7%). The prevalence decreased significantly in rheumatic VHD from 2009 to 2013 (from 42.8% to 32.8%, P<0.001), but increased markedly in congenital VHD (from 9.0% to 12.3%, P<0.001), ischemic VHD (from 9.2% to 11.3%, P=0.003) and degenerative VHD (from 8.8% to 14.5%, P<0.001). Meantime, the prevalence of ischemic VHD increased after the age of 45, similar to that of degenerative VHD. From 2009 to 2013, the proportion of patients with VHD undergoing open cardiac valvular surgery decreased (from 49.5% to 44.3%, P<0.001) and that of patients treated with general medication increased (from 49.2% to 54.1%, P<0.001). However, there was markedly increment in video-assisted thoracoscopic surgery (VATS) from 2009 to 2013 (from 0.3% to 4.4%, P<0.001). Increasing tendencies were showed in aortic mechanical valve replacement (from 32.1% to 34.5%, P=0.001) and double mechanical valve replacement (from 20.9% to 22.3%, P=0.035), especially in mitral valvuloplasty (from 8.5% to 15.7%, P<0.001). However, the proportion of patients undergoing bioprosthetic valve replacement decreased from 2009 to 2013 (from 26.3% to 15.5%, P<0.001).
Despite a significant shift from rheumatic towards degenerative etiology from 2009 to 2013, rheumatic VHD remains the leading etiology in Southern China, with a significant increase in the prevalence of ischemic, congenital and degenerative VHD. General medication and cardiac valvular surgery remain the main treatment options. The proportion of VATS increased markedly from 2009 to 2013, and mechanical valve replacement and mitral valvuloplasty showed an increasing tendency.
Epidemiological; valvular heart disease (VHD); etiology; cardiac valvular surgery
Boerhaave’s syndrome (BS), also known as “spontaneous rupture of the esophagus”, constitutes an emergency that requires early diagnosis if death or serious morbidity are to be prevented. First described in 1724, BS is thought to be more common than once thought. Its true incidence remains unknown. Mortality ranges between 20-40% with timely treatment but this rises to virtually 100% if treatment is delayed by more than 48 hours. This is unfortunately a common occurrence due to delayed diagnosis. The commonest precipitating factor is vomiting but BS can be truly “spontaneous”. The classical clinical presentation described consists of vomiting, chest pain, and subcutaneous emphysema. However, and contrary to popular belief, this triad is actually uncommon accounting for the frequently delayed diagnosis. A less recognised presenting feature of BS is with pneumothorax due to associated rupture of the parietal pleura. Pneumothorax has been shown to be present in more than 20% of cases of BS-sometimes with a coexistent pleural effusion (hydropneumothorax). This article aims to raise awareness about pneumothorax as the sole initial presenting feature of BS and alert clinicians to consider BS in the differential diagnosis of any patient with respiratory symptoms and a recent history of vomiting.
Boerhaave’s syndrome (BS); esophagus; perforation; pneumothorax; hydropneumothorax
Bootstrap is a computer intensive technique of resampling with replacement, which can be applied in many statistical analytical tests. The article describes the most frequent situations where bootstrap resampling can be applied in thoracic surgical research: variable selection for multivariable regression analysis, internal validation of regression equations, model validation. Practical examples for programming bootstrap in commercially available statistical software are finally reported.
Resampling statistics; bootstrap; risk modelling; thoracic surgery
A 48-year-old man with posterior mediastinal mass was diagnosed as functional mediastinal paraganglioma during surgical exploration via open thoracotomy in another hospital. The operation was terminated because of severe hypertension when touching the tumor. He was transferred to our center later. After systemic evaluation, the patient was medicated with oral alpha- and beta-blockades, as well as intravenous fluid resuscitation for two weeks. His blood pressure became stable and a second operation was planned. The tumor was removed completely via the thoracoscopic approach, and was finally confirmed as functional paraganglioma by immunohistochemistry. The patient recovered uneventfully after surgery, with no recurrence during one year follow-up visit.
Thoracoscopic resection; functional mediastinal paraganglioma; case report
Simultaneous improvement in respiratory maintenance and bleeding control increases survival of patients with life-threatening hemoptysis. Endobronchial blockade is an effective method and is preferred for emergency hemostasis. However, when the volume of hemoptysis is high, emergency hemostasis and airway maintenance are impossible due to flooding of blood into the airway. We used extracorporeal membrane oxygenation (ECMO) to overcome these limitations in a patient with massive hemoptysis due to severe blunt trauma and succeeded in saving the life by inducing a near-total airway obstruction.
Hemoptysis; extracorporeal membrane oxygenation (ECMO); hemostasis; trauma
We hypothesized that pretreatment with sivelestat therapy could attenuate ventilator-induced lung injury (VILI) and lung inflammation in a rat model.
The neutrophil elastase inhibitor was administered intraperitoneally 30 min before and at the initiation of ventilation. The rats were categorized as (I) sham group; (II) VILI group; (III) sivelestat group; (IV) early sivelestat group. Wet-to-dry weight ratio, bronchoalveolar lavage fluid (BALF) neutrophil and protein, tissue malondialdehyde (MDA) and histologic VILI scores were investigated.
The ratio of wet-to-dry weight, BALF neutrophil and protein, tissue MDA and VILI scores were significantly increased in the VILI group compared to the sham group [3.85±0.32 vs. 9.05±1.02, P<0.001; (0.89±0.93)×104
vs. (7.67±1.41)×104 cells/mL, P<0.001; 2.34±0.47 vs. 23.01±3.96 mg/mL, P<0.001; 14.43±1.01 vs. 36.56±5.45 nmol/mg protein, P<0.001; 3.78±0.67 vs. 7.00±1.41, P<0.001]. This increase was attenuated in the early sivelestat group compared with the sivelestat group [wet-to-dry ratio: 6.76±2.01 vs. 7.39±0.32, P=0.032; BALF neutrophil: (5.56±1.13)×104
vs. (3.89±1.05)×104 cells/mL, P=0.021; BALF protein: 15.57±2.32 vs. 18.38±2.00 mg/mL, P=0.024; tissue MDA: 29.16±3.01 vs. 26.31±2.58, P=0.049; VILI scores: 6.33±1.41 vs. 5.00±0.50, P=0.024].
Pretreatment with a neutrophil elastase inhibitor attenuates VILI in a rat model.
Ventilator-induced lung injury (VILI); neutrophil elastase
Thoracoscopic anatomic segmentectomy is usually more complex than lobectomy. This video shows a 58-year-old female who suffered from limited bronchiectasis of the lingular segment of the left upper lung and a pericardial cyst on the same side. Both of these benign thoracic diseases can cause pleural adhesions. Repeated chronic inflammation contributes to hypervascularity and lymph node enlargement, making surgery more difficult. We used single-direction thoracoscopic segmentectomy via a three-port approach and successfully removed the lingula and pericardial cyst.
Pulmonary segmental resection; bronchiectasis; pericardial cyst; total thoracoscopy
A 50-year-old active male with a smoking history of 30 years (20 cigarettes per day) was admitted to hospital because of more than one month’s cough without sputum. No comorbidity was present. The preoperative examination showed: blood test normal, ECG normal, cardio-pulmonary function normal, chest computed tomography (CT) display right upper lobe (RUL) mass of 5 cm diameter. Bronchoscopy examination and biopsy indicated large cell neuroendocrine carcinoma (LCNEC) in the take-off of RUL bronchus. No metastatic focus was found after emission computed tomography (ECT) scan of whole body bone, abdominal US scanning and brain MR. After initial evaluation, the clinical stage before operation was cT2bN0M0 (IIA stage). A selective video-assisted thoracic surgery (VATS) operation was arranged after 9 days of smoking cessation. Lateral position, one 10 mm trocar for camera in the 7th intercostals space in the mid-auxiliary line, 4 cm trocar for operation in the 4th intercostal space in the anterior axillary line, 15 mm trocar for auxiliary operation in the 8th intercostal space in the scapula line, the patient received VATS RUL lobectomy, plus systemic mediastinal lymph nodes dissection. The procedure of 200 minutes operation was smooth with blood loss of about 150 mL. Chest tube was removed 6 days after operation, and the patient discharged 11 days after the operation; The post-operation pathological examination showed RUL LCNEC, and the pathological stage was pT2bN0M0R0 (IIA stage). The patient has received four cycles of EP adjuvant chemotherapy per 21 days and is still alive without disease recurrence and metastasis after re-examination.
Carcinoma; non-small-cell lung; thoracic surgery; video-assisted; pneumonectomy; thoracic surgical procedures
Video-assisted thoracoscopic surgery (VATS) has become a routine procedure for stage I and II lung cancers. However, in the presence of multiple metastasized lymph nodes invading the pulmonary artery or its major branches, the pulmonary artery have to be resected partially or sleeve resected, which could be extremely risky under thoracoscopic conditions. In order to reduce the risk of bleeding, an experienced thoracic surgeon would occlude the inflow and outflow of the pulmonary artery before anatomically dissecting the area of the pulmonary artery with tumor invasion. Different centers may use different clamping techniques and devices. Here, we report our technique of totally thoracoscopic left upper lobectomy with systematic lymph nodes dissection under pulmonary artery clamping for a 49-year-old woman with left upper lobe carcinoma. The video demonstrates our thinking and surgical process.
Video-assisted thoracoscopic surgery (VATS); left pulmonary artery clamping; left lower lobe pulmonary artery; left upper lobectomy; systematic lymph node dissection
Giant emphysamtous bulla (GEB) can negatively affect the pulmonary functions of chronic obstructive pulmonary diseases (COPD) patients, including decreased forced expiratory volume in 1 s (FEV1) and increased functional residual capacity (FRC). The aim of this study was to evaluate the efficacy of endobronchial valve (EBV) to treat bullae and to find efficacy predictors of successful treatment.
Five COPD patients with giant bulla were treated using EBVs. Before the EBV deployment, collateral ventilation (CV) between the targeted and adjacent lobes was evaluated with Chartis system.
In the two patients with negative CV, the mean value of FEV1 increased from 27.1±11.4% of predicted value before EBV treatment to 32.8±12.0% (P>0.05) at 1 month after EBV treatment, than to 31.7±24.5% (P>0.05) at 6 months after EBV treatment. Only one patient, whose bulla occupied the whole right middle lung, displayed sustained improvement of FEV1 at 6 months after EBV treatment. In the three patients with positive CV, the mean value of FEV1 decreased from 28.8±19.0% of predicted value before EBV treatment to 24.8±12.6% (P>0.05) at 1 month after EBV treatment, than to 22.1±10.8% (P>0.05) at 6 months after EBV treatment.
EBV is an effective measure to treat highly selected COPD patients with giant bulla. Although, EBV treatment can achieve transient improvement of lung function at patients with CV negative bulla, long-term benefit was merely observed at the patient with a bulla at right middle lobe (RML).
Endobronchial valve (EBV); bulla; chronic obstructive pulmonary diseases (COPD); collateral ventilation (CV)
Rhodococcus equi (R. equi) is an uncommon gram positive organism. It is a rare but recognized pathogen in humans and has emerged as an important cause of morbidity and mortality among immunocompromised patients. Generally, R. equi infection needs combined treatment with effective antibiotics, and often requires the immune adjuvant therapy. Here we reported a 49-year-old man presented dyspnea with fever, skin ulcer for 5 months, and the final diagnosis was diffuse large B cell lymphoma with R. equi septicemia and pneumonia, the treatment was failure, the blood culture was always positive during the course of disease, though he was given combined treatment with effective antibiotics, perhaps the immune reconstitution or immune supportive treatment was more important.
Rhodococcus equi (R. equi); diffuse large B cell lymphoma; immunologic reconstitution; combined treatment