Exhaled hydrogen sulfide in patients with chronic obstructive pulmonary disease and its correlation with exhaled nitric oxide / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Exhaled nitric oxide (NO) is a noninvasive biomarker of airway inflammation in pulmonary diseases. Hydrogen sulfide (H2S), as the third member of the gasotransmitter family, is involved in the pathophysiological process in lung diseases. H2S also exists in exhaled breath and can be sampled non-invasively. The study investigated the level of exhaled H2S in patients with chronic obstructive pulmonary disease (COPD) and its correlation with exhaled NO.</p><p><b>METHODS</b>Levels of exhaled NO and H2S, lung function, and cell differential counts in induced sputum were studied in 19 patients with acute exacerbation of COPD (AECOPD), 19 patients with stable COPD and seven healthy smoke controls.</p><p><b>RESULTS</b>Exhaled H2S levels were similar in patients with AECOPD (10.0 parts per billion (ppb), 8.0-13.0 ppb), stable COPD (10.0 ppb, 9.0-12.0 ppb), and healthy controls (9.0 ppb, 8.0-16.0 ppb) (P > 0.05). Exhaled NO levels were similar in patients with AECOPD (155.0 ppb, 129.0-190.0 ppb), stable COPD (154.0 ppb, 133.0-175.0 ppb) and healthy controls (165.0 ppb, 112.0-188.0 ppb) (P > 0.05). Exhaled H2S levels correlated positively with exhaled NO in all healthy controls and patients with COPD (r=0.467, P < 0.01). No significant correlation was found between the exhaled H2S level and percentage of predicted FEV1 (P > 0.05) and proportion of different cell types in induced sputum (P > 0.05).</p><p><b>CONCLUSIONS</b>There is a correlation between exhaled H2S and exhaled NO. The role of exhaled H2S in airway inflammation in COPD still needs further investigation.</p>

Animal model of grading skeletal muscle contusion due to blunt impact in rats / 法医学杂志

OBJECTIVE@#To establish a new animal model of grading skeletal muscle contusions that could be controllable and repetitive.@*METHODS@#The rats' gastrocnemius was injured by a new weight-dropping device designed. The force acting on gastrocnemius with a comparatively constant duration and inducing elastic deformation of the gastrocnemius was expressed with velocity (v) and deformation (DF). Instant velocity was changed to create gastrocnemius contusions. Pathological changes of gastrocnemius were graded by the gross and histological examinations of 39 rats.@*RESULTS@#At low level of impact (v: 2 m/s, DF: 5.5 mm), mild injuries were detected in epimysium and superficial layer of gastrocnemius. At moderate level of impact (v: 2.5 m/s, DF: 6.5 mm), the injuries were observed in epimysium and whole gastrocnemius. At high level of impact (v: 3 m/s, DF: 7.5 mm), severe injuries were seen deeper to soleus with more extensive skeletal muscle damage.@*CONCLUSION@#Grading of skeletal muscle blunt force contusion is created by parameter of velocity and muscle deformation. The model could be used for further research on skeletal muscle contusions.