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1.
In airway diseases, smooth muscle cells can proliferate at exaggerated rates; thus, the identification of endogenous pathways that limit proliferative responses is important. Here we show that human airway smooth muscle express type I nitric oxide synthase (NOS), which results in inhibition of DNA synthesis and cell proliferation. In addition, superoxide dismutase (SOD), a cell-permeable mimetic that increases the biological half-life and therefore enhances the biological activity of endogenously released nitric oxide (NO), or NO-releasing drugs also greatly reduce DNA synthesis and cell proliferation. Observations in this study have important clinical implications: 1) NOS inhibition may exacerbate airway disease and 2) inhaled SOD/mimetics or NO/nitrovasodilators may be therapies for the treatment of asthma or chronic obliterative pulmonary disease.  相似文献   

2.
Lung epithelium guarantees gas-exchange (performed in the alveoli) and protects from external insults (pathogens, pollutants…) present within inhaled air. Both functions are facilitated by secretions lining airway surface liquid, mucus (in the upper airways) and pulmonary surfactant (in the alveoli). Mucins, the main glycoproteins present within the mucus, are responsible for its rheologic properties and participate in lung defense mechanisms. In parallel, lung collectins are pattern recognition molecules present in pulmonary surfactant that also modulate lung defense. During chronic airways diseases, excessive protease activity can promote mucus hypersecretion and degradation of lung collectins and therefore contribute to the pathophysiology of these diseases. Importantly, secretion of local and systemic anti-proteases might be crucial to equilibrate the protease/anti-protease unbalance and therefore preserve the function of lung host defense compounds and airway surface liquid homeostasis. In this review we will present information relative to proteases able to modulate mucin production and lung collectin integrity, two important compounds of innate immune defense. One strategy to preserve physiological mucus production and collectin integrity during chronic airways diseases might be the over-expression of local ‘alarm’ anti-proteases such as SLPI and elafin. Interestingly, a cross-talk between lung collectins and anti-protease activity has recently been described, implicating the presence within the lung of a complex network between proteases, anti-proteases and pattern recognition molecules, which aims to keep or restore homeostasis in resting or inflamed lungs.  相似文献   

3.
Potential antimicrobial effects of sequential applications of tissue‐tolerable plasma (TTP) and the conventional liquid antiseptic octenidine dihydrochloride (ODC) were investigated. 34 patients with chronic leg ulcers were treated with TTP, ODC or a combination of both. The bacterial colonization was measured semi‐quantitatively before and immediately after treatment and changes in the microbial strains' compositions before and after antiseptic treatments were analyzed. All antiseptic procedures reduced the bacterial counts significantly. The sequential application of TTP and ODC displayed the highest antimicrobial efficacy. Me combined use of TTP and conventional antiseptics might represent the most efficient strategy for antiseptic treatment of chronic wounds. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)  相似文献   

4.
Inhaled pollutants produce effects in virtually all organ systems in our body and have been linked to chronic diseases including hypertension, atherosclerosis, Alzheimer's and diabetes. A neurohormonal stress response (referred to here as a systemic response produced by activation of the sympathetic nervous system and hypothalamus–pituitary–adrenal (HPA)-axis) has been implicated in a variety of psychological and physical stresses, which involves immune and metabolic homeostatic mechanisms affecting all organs in the body. In this review, we provide new evidence for the involvement of this well-characterized neurohormonal stress response in mediating systemic and pulmonary effects of a prototypic air pollutant — ozone. A plethora of systemic metabolic and immune effects are induced in animals exposed to inhaled pollutants, which could result from increased circulating stress hormones. The release of adrenal-derived stress hormones in response to ozone exposure not only mediates systemic immune and metabolic responses, but by doing so, also modulates pulmonary injury and inflammation. With recurring pollutant exposures, these effects can contribute to multi-organ chronic conditions associated with air pollution. This review will cover, 1) the potential mechanisms by which air pollutants can initiate the relay of signals from respiratory tract to brain through trigeminal and vagus nerves, and activate stress responsive regions including hypothalamus; and 2) the contribution of sympathetic and HPA-axis activation in mediating systemic homeostatic metabolic and immune effects of ozone in various organs. The potential contribution of chronic environmental stress in cardiovascular, neurological, reproductive and metabolic diseases, and the knowledge gaps are also discussed. This article is part of a Special Issue entitled Air Pollution, edited by Wenjun Ding, Andrew J. Ghio and Weidong Wu.  相似文献   

5.

Background

There is considerable evidence from the literature that children with chronic lung disease of infancy (CLD) have abnormal pulmonary function in childhood and this could have an impact on their life quality and overall health. There are similarities between CLD and asthma, and corticosteroids are the mainstay treatment for asthma. Many physicians use inhaled corticosteroids in children with CLD with no evidence. Therefore we wish to conduct a randomized double-blinded placebo controlled trial to test for the role of inhaled corticosteroids in children aged from3 to 9 years with a history of CLD. Our primary hypothesis will be that inhaled corticosteroids are beneficial in children with CLD.

Methods

Our primary hypothesis is that using inhaled steroids; Beclomethasone Dipropionate (QVAR) 100 mcg 2 puffs 2 times a day for 6 weeks will improve the respiratory system resistance and the quality of life in children with CLD.

Discussion

We propose that Beclomethasone Dipropionate (QVAR) will affect the pulmonary function after 6 weeks of treatment. In summary we think that our study will highlight knowledge on whether the use of inhaled steroids is clinically effective for CLD.  相似文献   

6.
In anaesthetized paralysed, mechanically ventilated pigs, the vascular and respiratory effects of 80 ppm nitric oxide (NO) inhaled for 6 min were evaluated. To evoke different levels of smooth muscle contraction ET-1 or PAF, mediators involved in pulmonary disorders, were used. In control conditions, inhaled NO caused selective pulmonary vasodilatation without affecting respiratory resistances. This pulmonary vascular activity influenced the distensibility of the respiratory system and decreased inspiratory work. ET-1 administration significantly increased pulmonary arterial pressure and modestly changed mechanical properties of the respiratory system, while PAF caused potent vasoconstriction and bronchoconstriction associated with a marked change in volume-pressure relationship. In both cases, the changes in vascular and mechanical properties of the respiratory system increased inspiratory work. The vascular and respiratory activities of inhaled NO were correlated with preconstriction levels. The data show that the combination of vascular and respiratory effects improves pulmonary function, suggesting that inhalation of NO is a possible therapeutic approach for obstructive and inflammatory pulmonary diseases.  相似文献   

7.
Previous in vivo studies indicate that inhaled nitric oxide (NO) decreases nitric oxide synthase (NOS) activity and that this decrease is associated with significant increases in pulmonary vascular resistance (PVR) upon the acute withdrawal of inhaled NO (rebound pulmonary hypertension). In vitro studies suggest that superoxide and peroxynitrite production during inhaled NO therapy may mediate these effects, but in vivo data are lacking. The objective of this study was to determine the role of superoxide in the decrease in NOS activity and rebound pulmonary hypertension associated with inhaled NO therapy in vivo. In control lambs, 24 h of inhaled NO (40 ppm) decreased NOS activity by 40% (P<0.05) and increased endothelin-1 levels by 64% (P<0.05). Withdrawal of NO resulted in an acute increase in PVR (60.7%, P<0.05). Associated with these changes, superoxide and peroxynitrite levels increased more than twofold (P<0.05) following 24 h of inhaled NO therapy. However, in lambs treated with polyethylene glycol-conjugated superoxide dismutase (PEG-SOD) during inhaled NO therapy, there was no change in NOS activity, no increase in superoxide or peroxynitrite levels, and no increase in PVR upon the withdrawal of inhaled NO. In addition, endothelial NOS nitration was 18-fold higher (P<0.05) in control lambs than in PEG-SOD-treated lambs following 24 h of inhaled NO. These data suggest that superoxide and peroxynitrite participate in the decrease in NOS activity and rebound pulmonary hypertension associated with inhaled NO therapy. Reactive oxygen species scavenging may be a useful therapeutic strategy to ameliorate alterations in endogenous NO signaling during inhaled NO therapy.  相似文献   

8.
Pulmonary hypertension (PHT) in neonates is often refractory to the current best therapy, inhaled nitric oxide (NO). The utility of a new class of pulmonary vasodilators, Rho-kinase (ROCK) inhibitors, has not been examined in neonatal animals. Our objective was to examine the activity and expression of RhoA/ROCK in normal and injured pulmonary arteries and to determine the short-term pulmonary hemodynamic (assessed by pulse wave Doppler) effects of ROCK inhibitors (15 mg/kg ip Y-27632 or 30 mg/kg ip fasudil) in two neonatal rat models of chronic PHT with pulmonary vascular remodeling (chronic hypoxia, 0.13 Fi(O(2)), or 1 mg.kg(-1).day(-1) ip chronic bleomycin for 14 days from birth). Activity of the RhoA/ROCK pathway and ROCK expression were increased in hypoxia- and bleomycin-induced PHT. In both models, severe PHT [characterized by raised pulmonary vascular resistance (PVR) and impaired right ventricular (RV) performance] did not respond acutely to inhaled NO (20 ppm for 15 min) or to a single bolus of a NO donor, 3-morpholinosydnonimine hydrochloride (SIN-1; 2 mug/kg ip). In contrast, a single intraperitoneal bolus of either ROCK inhibitor (Y-27632 or fasudil) completely normalized PVR but had no acute effect on RV performance. ROCK-mediated vasoconstriction appears to play a key role in chronic PHT in our two neonatal rat models. Inhibitors of ROCK have potential as a testable therapy in neonates with PHT that is refractory to NO.  相似文献   

9.
脂多糖(Lipopolysaccharide,LPS)是革兰阴性杆菌细胞壁的主要组成成分,也是一种很强的炎症反应和氧化应激诱导剂。呼吸道上皮是机体防御外界细菌、病毒、香烟烟雾等生物和化学因素损伤的天然屏障,在维持呼吸道局部微环境稳态中可发挥重要作用,也是吸入性药物治疗的主要靶细胞。呼吸道上皮结构完整性缺陷或功能紊乱还参与了哮喘、慢性阻塞性肺疾病等多种肺部疾病的发生和发展。LPS可引起呼吸道上皮损伤,但其具体的分子机制目前尚不清楚。p38丝裂原活化蛋白激酶(P38mitogen-activated protein kinase,p38 MAPK)作为MAPK家族四个亚家族成员之一,包含四个成员:p38α、p38β、p38γ和p38δ,可通过经典和非经典的p38 MAPK信号通路激活方式及通过激酶活性无关的功能参与调控炎症反应、细胞生长、细胞分化和细胞死亡等多种病理生理过程。本文就p38 MAPK信号通路在LPS致呼吸道上皮损伤中的作用做一综述。  相似文献   

10.
11.
It is now clear that NSPs (neutrophil serine proteases), including elastase, Pr3 (proteinase 3) and CatG (cathepsin G) are major pathogenic determinants in chronic inflammatory disorders of the lungs. Two unglycosylated natural protease inhibitors, SLPI (secretory leucocyte protease inhibitor) and elafin, and its precursor trappin-2 that are found in the lungs, have therapeutic potential for reducing the protease-induced inflammatory response. This review examines the multifaceted roles of SLPI and elafin/trappin-2 in the context of their possible use as inhaled drugs for treating chronic lung diseases such as CF (cystic fibrosis) and COPD (chronic obstructive pulmonary disease).  相似文献   

12.
Sustained therapeutic hypercapnia prevents pulmonary hypertension in experimental animals, but its rescue effects on established disease have not been studied. Therapies that inhibit Rho-kinase (ROCK) and/or augment nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) signaling can reverse or prevent progression of chronic pulmonary hypertension. Our objective in the present study was to determine whether sustained rescue treatment with inhaled CO(2) (therapeutic hypercapnia) would improve structural and functional changes of chronic hypoxic pulmonary hypertension. Spontaneously breathing pups were exposed to normoxia (21% O(2)) or hypoxia (13% O(2)) from postnatal days 1-21 with or without 7% CO(2) (Pa(CO(2)) elevated by ~25 mmHg) or 10% CO(2) (Pa(CO(2)) elevated by ~40 mmHg) from days 14 to 21. Compared with hypoxia alone, animals exposed to hypoxia and 10% CO(2) had significantly (P < 0.05) decreased pulmonary vascular resistance, right-ventricular systolic pressure, right-ventricular hypertrophy, and medial wall thickness of pulmonary resistance arteries as well as decreased lung phosphodiesterase (PDE) V, RhoA, and ROCK activity. Rescue treatment with 10% CO(2), or treatment with a ROCK inhibitor (15 mg/kg ip Y-27632 twice daily from days 14 to 21), also increased pulmonary arterial endothelial nitric oxide synthase and lung NO content. In contrast, cGMP content and cGMP-dependent protein kinase (PKG) activity were increased by exposure to 10% CO(2), but not by ROCK inhibition with Y-27632. In vitro exposure of pulmonary artery smooth muscle cells to hypercapnia suppressed serum-induced ROCK activity, which was prevented by inhibition of PKG with Rp-8-Br-PET-cGMPS. We conclude that sustained hypercapnia dose-dependently inhibited ROCK activity, augmented NO-cGMP-PKG signaling, and led to partial improvements in the hemodynamic and structural abnormalities of chronic hypoxic PHT in juvenile rats. Increased PKG content and activity appears to play a major upstream role in CO(2)-induced suppression of ROCK activity in pulmonary arterial smooth muscle.  相似文献   

13.
The rise of antimicrobial resistant (AMR) bacteria is a global public health threat. AMR Achromobacter bacteria pose a challenging clinical problem, particularly for those with cystic fibrosis (CF) who are predisposed to chronic bacterial lung infections. Lytic bacteriophages (phages) offer a potential alternative to treat AMR infections, with the possible benefit that phage selection for resistance in target bacteria might coincide with reduced pathogenicity. The result is a genetic “trade-off,” such as increased sensitivity to chemical antibiotics, and/or decreased virulence of surviving bacteria that are phage resistant. Here, we show that two newly discovered lytic phages against Achromobacter were associated with stabilization of respiratory status when deployed to treat a chronic pulmonary infection in a CF patient using inhaled (nebulized) phage therapy. The two phages demonstrate traits that could be generally useful in their development as therapeutics, especially the possibility that the phages can select for clinically useful trade-offs if bacteria evolve phage resistance following therapy. We discuss the limitations of the current study and suggest further work that should explore whether the phages could be generally useful in targeting pulmonary or other Achromobacter infections in CF patients.  相似文献   

14.
The reason why particular inhaled Ags induce allergic sensitization while others lead to immune tolerance is unclear. Along with a genetic predisposition to atopy, intrinsic characteristics of these Ags must be important. A common characteristic of many allergens is that they either possess proteinase activity or are inhaled in particles rich in proteinases. Many allergens, such as house dust mite and cockroach allergens, have the potential to activate the proteinase-activated receptor (PAR)-2. In this study, we report that PAR-2 activation in the airways at the same time as exposure to inhaled Ags induces allergic sensitization, whereas exposure to Ag alone induces tolerance. BALB/c mice were administered OVA with a PAR-2 activating peptide intranasally. Upon allergen re-exposure mice developed airway inflammation and airway hyperresponsiveness, as well as OVA-specific T cells with a Th2 cytokine profile when restimulated with OVA in vitro. Conversely, mice given OVA alone or OVA with a PAR-2 control peptide developed tolerance. These tolerant mice did not develop airway inflammation or airway hyperresponsiveness, and developed OVA-specific T cells that secreted high levels of IL-10 when restimulated with OVA in vitro. Furthermore, pulmonary dendritic cell trafficking was altered in mice following intranasal PAR-2 activation. Finally, we showed that PAR-2-mediated allergic sensitization was TNF-dependent. Thus, PAR-2 activation in the airways could be a critical factor in the development of allergic sensitization following mucosal exposure to allergens with serine proteinase activity. Interfering with this pathway may prove to be useful for the prevention or treatment of allergic diseases.  相似文献   

15.
曾昭定  戴爱国  蒋永亮 《生物磁学》2014,(9):1769-1771,1708
硫氧还蛋白系统是由硫氧还蛋白(thioredoxin,Trx),硫氧还蛋白还原酶(thioredoxinreductase,TrxR)和还原型辅酶Ⅱ(NADPH)组成的多功能小分子蛋白系统,广泛表达的硫氧还蛋白作为蛋白质二硫键的还原酶,它参与很多生理过程,并发挥重要生物学功能,包括调节机体的氧化还原反应、抑制细胞凋亡、调节转录因子DNA结合活性以及免疫应答等,其中一重要作用是参与调节细胞氧化还原状态以对抗氧化应激。因此在一些炎症性疾病如慢性阻塞性肺疾病、急性呼吸窘迫综合征、肺间质疾病、哮喘、肺结节病等的发生发展中扮演重要角色,本文对硫氧还蛋白系统在慢性阻塞性肺疾病中的抗氧化作用作一综述。  相似文献   

16.
Bronchiectasis is a chronic irreversible airway abnormality associated with infectious agents that either cause or superinfect the airways. While the role of bacteria is well studied, much remains to be determined about fungi in both cystic fibrosis- and non-cystic fibrosis-related bronchiectasis. The airway is constantly exposed to inhaled ambient moulds of which Aspergillus represent the most ubiquitous. In a normal healthy host, this situation is of little consequence. The presence of anatomical or immunological abnormalities such as those in bronchiectasis leads to a range of fungal-related pathologies from asymptomatic airway colonization to fungal sensitization, allergic bronchopulmonary aspergillosis or chronic pulmonary aspergillosis. These entities are difficult to recognize, diagnose and treat due in part to a lack of validated biomarkers. Our true understanding of the complex relationships that regulate fungal–host interactions is still in its infancy and, several questions remain. This includes if fungal epidemiology in bronchiectasis is uniform across countries, and to what extent immunopathological mechanisms—related to fungal airway infections—occurs in different disease states. Specific triggers to allergic or infectious responses to Aspergillus require further exploration. How transition occurs between allergic and invasive phenotypes and their respective biomarkers is also important. Whether anti-fungal treatment is warranted in all cases and what the optimal management strategy is, particularly when treatment should commence and its expected duration remains unclear. Further research is clearly necessary and should be prioritized to better understand the clinical effects and impact of Aspergillus in the setting of bronchiectasis.  相似文献   

17.
The narrow therapeutic index, potential toxicity, and need to monitor plasma concentrations make theophyllines difficult to use. Other drugs provide comparable or better bronchodilator and prophylactic efficacy. In asthma theophyllines should be considered for chronic stable asthma when treatment with optimal doses of inhaled steroids and bronchodilators fails to provide adequate control; for nocturnal asthma; and for prophylaxis and relief of symptoms in children and adults when inhaled treatment cannot be given. In general, theophyllines cannot be recommended for chronic airflow obstruction. A trial of theophylline is reasonable in individual patients whose symptoms remain troublesome despite a trial of steroids and optimal doses of inhaled bronchodilators.  相似文献   

18.
Secondary pulmonary hypertension is a frequent condition after heart valve surgery. It may significantly complicate the perioperative management and increase patients' morbidity and mortality. The treatment has not been yet completely defined principally because of lack of the selectivity of drugs for the pulmonary vasculature. The usage of inhaled milrinone could be the possible therapeutic option. Inodilator milrinone is commonly used intravenously for patients with pulmonary hypertension and ventricular dysfunction in cardiac surgery. The decrease in systemic vascular resistance frequently necessitates concomitant use of norepinephrine. Pulmonary vasodilators might be more effective and also devoid of potentially dangerous systemic side effects if applied by inhalation, thus acting predominantly on pulmonary circulation. There are only few reports of inhaled milrinone usage in adult post cardiac surgical patients. We reported 2 patients with severe pulmonary hypertension after valve surgery. Because of desperate clinical situation, we decided to use the combination of inhaled and intravenous milrinone. Inhaled milrinone was delivered by means of pneumatic medication nebulizer dissolved with saline in final concentration of 0.5 mg/ml. The nebulizer was attached to the inspiratory limb of the ventilator circuit, just before the Y-piece. We obtained satisfactory reduction in mean pulmonary artery pressure in both patients, and they were successfully extubated and discharged. Although it is a very small sample of patients, we conclude that the combination of inhaled and intravenous milrinone could be an effective treatment of secondary pulmonary hypertension in high-risk cardiac valve surgery patient. The exact indications for inhaled milrinone usage, optimal concentrations for this route, and the beginning and duration of treatment are yet to be determined.  相似文献   

19.
Group living is favorable to pathogen spread due to the increased risk of disease transmission among individuals. Similar to individual immune defenses, social immunity, that is antiparasite defenses mounted for the benefit of individuals other than the actor, is predicted to be altered in social groups. The eusocial honey bee (Apis mellifera) secretes glucose oxidase (GOX), an antiseptic enzyme, throughout its colony, thereby providing immune protection to other individuals in the hive. We conducted a laboratory experiment to investigate the effects of group density on social immunity, specifically GOX activity, body mass and feeding behavior in caged honey bees. Individual honeybees caged in a low group density displayed increased GOX activity relative to those kept at a high group density. In addition, we provided evidence for a trade‐off between GOX activity and body mass: Individuals caged in the low group density had a lower body mass, despite consuming more food overall. Our results provide the first experimental evidence that group density affects a social immune response in a eusocial insect. Moreover, we showed that the previously reported trade‐off between immunity and body mass extends to social immunity. GOX production appears to be costly for individuals, and potentially the colony, given that low body mass is correlated with small foraging ranges in bees. At high group densities, individuals can invest less in social immunity than at low densities, while presumably gaining shared protection from infection. Thus, there is evidence that trade‐offs at the individual level (GOX vs. body mass) can affect colony‐level fitness.  相似文献   

20.
Asthma is an increasing global health problem, and many patients continue to suffer from chronic symptoms. However, current therapy with inhaled corticosteroids and a long-acting inhaled beta(2)-agonist is highly effective, safe and inexpensive. This poses a major hurdle to the development of new therapies that aim to improve on current treatments. An important unmet need is the treatment of severe asthma, which has different characteristics to mild and moderate asthma and is more similar to chronic obstructive pulmonary disease. Several new treatments are now under development but many of them are too specific, targeting a single receptor, enzyme or mediator, and are unlikely to have a major clinical impact. Another unmet need is the development of an effective oral therapy for mild and moderate asthma, but it is unlikely that such a treatment will be discovered because side effects might be a major problem. Prospects for a cure are currently remote but might arise from the development of vaccines that target the aberrant immune function in asthma.  相似文献   

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