The morbidity and mortality of pulmonary infection are high among infectious diseases worldwide. Rapid and accurate etiological diagnosis is the key to timely and effective treatment. Metagenomic next-generation sequencing (mNGS) technology has brokenthrough the limitations of traditional pathogenic microorganism detection methods and improved the detection rate of pathogens. In this paper, the application and advantages of mNGS technology in the diagnosis of bacteria, fungi, viruses and mixed infections in the lungs are analyzed, and the challenges and breakthroughs in RNA detection, wall breaking of firmicutes and host DNA clearance are described, in order to achieve targeted and accurate etiological diagnosis through mNGS, so as to effectively treat pulmonary infections.
ObjectiveTo explore the levels of serum leptin,TNF-α,IL-8 and hypersensitivity C-reactive protein (hs-CRP) in stable COPD patients with different body mass index (BMI). Methods30 healthy controls with BMI 18.5 to 23.9 kg/m2 and 105 patients with stable COPD were recruited in the study. The serum levels of leptin,TNF-α,and IL-8 were determined by radioimmunoassay and hs-CRP level was determined by versatile biochemical automatic analyzer. The COPD patients were divided into a low BMI group (BMI<18.5 kg/m2,n=32),a normal BMI group (BMI 18.5-23.9 kg/m2,n=48),and a high BMI group (BMI≥23.9 kg/m2,n=25). ResultsSerum leptin level in the COPD patients was significantly reduced compared with the control subjects (P<0.05). Serum leptin levels were reduced in the low BMI and the high BMI groups compare with the normal BMI group [(7.89±3.16)ng/L and (10.52±5.98)ng/L vs. (13.04±5.73) ng/L,P<0.01 or P<0.05]. Leptin level in the low BMI group was lower than that in the high BMI group (P<0.05). Serum TNF-α levels were significantly increased in the low BMI group compared with the normal BMI and high BMI groups [(229.39±89.57)μg/L vs. (180.06±74.24) μg/L and (189.46±82.41) μg/L,P<0.01]. Serum TNF-α level in the COPD patients was significantly increased compared with the control subjects [(192.37±83.65) μg/L vs. (178.59±60.38) μg/L,P<0.05]. The IL-8 levels were not significant different among three BMI groups with COPD. The hs-CRP level in the high BMI group was higher than that in the low BMI and normal BMI groups (P<0.05). ConclusionLeptin and TNF-α may be involved in weight-loss of COPD malnutritional patients.
ObjectiveTo investigate the expression and significance of cysteine-rich protein 61 (Cyr61) in patients with chronic obstructive pulmonary disease (COPD).MethodsBetween September 2017 and September 2018, 27 patients with benign tumor needing to surgical therapy, were divided into COPD group (15 patients) and non-COPD group (12 patients), according to lung function. Lung tissues were selected at the distance at least 5 cm from the tumor. The levels of Cyr61, interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) in serum were determined by enzyme-linked immunosorbent assay. Meanwhile, the expressions of Cyr61 in lung tissues were measured by immunohistochemistry technology between two groups. Furthermore, correlations among Cyr61, IL-8, MCP-1, smoking index, forced expiratory volume in the 1st second as percentage of predicted values (FEV1%pred), scores of COPD Assessment Test (CAT) were analyzed.ResultsSerum Cyr61, IL-8, MCP-1 levels were significantly higher in patients with COPD than in the non-COPD group (P<0.05), (2409.80±893.87)pg/mL, (76.27±10.53)pg/mL, (173.67±42.64)pg/mL vs. (1065.42±158.83)pg/mL, (57.33±8.29)pg/mL, (138.42±27.62)pg/mL, respectively. By immunohistochemistry technology, the expression levels of Cyr61 in lung epithelial cells and in lung macrophage cells of COPD patients were higher than in the non-COPD group (P<0.01). Positive correlations were found between serum IL-8, serum MCP-1, CAT scores, smoking index and serum Cyr61 (r=0.674, 0.566, 0.602, and 0.755, P=0.006, 0.028, 0.018, and 0.003, respectively) in COPD group. Furthermore, in COPD group, there were also positive correlations between serum IL-8, serum MCP-1, CAT scores, smoking index and intrapulmonary Cyr61 (r=0.542, 0.635, 0.809, and 0.580, P=0.037, 0.011, 0.001, and 0.038 respectively). Inverse correlation was found between serum Cyr61 and FEV1%pred (r=–0.772, P<0.01), and the same as between intrapulmonary Cyr61 and FEV1%pred (r=–0.683, P<0.01).ConclusionsCyr61 highly expresses in serum and in lung tissues of patients with COPD, and its expression is correlated with lung function of patients. The results indicate that Cyr61 may interact with IL-8 and MCP-1 in the pathogenesis of chronic obstructive pulmonary disease.
Objective To study the concentration of neurotrophins( including NGF, BDNF, NT3 and NT4) in the lung of SD rats infected by respiratory syncytial virus( RSV) , and to explore the relationship between the concentration of the neurotrophins, airway hyperresponsiveness and airway neural plasticity.Methods Twenty SD newborn rats were randomly divided into a control group and a RSV-infected group with ten rats in each group. The RSV-infected group were infected with 5 ×104 TCID50/0. 1 mL RSV each week. After 8 weeks, the bronchial responsiveness of the SD rats was assessed. The bronchial inflammation was assessed by HE staining with left lung. Synaptophysin and neurofilament expressions in the lung of SD rats were assayed by the immunohistochemistry staining. In situ hybridization was used to detect the RSV RNA in the lung. The concentration of neurotrophins in the lung of SD rats were detected by ELISA. Results The RSV-infected group showed elevated airway hyperresponsiveness and more inflammatory cells infiltrated in the lung; In situ hybridization showed positive signal of RSV RNA in lung interstitium of the RSV-infected rats. Synaptophysin and neurofilame levels in the airway were increased in the RSV-infected group. Supernatant levels of NGF and BDNF were significantly increased compared with the control group ( P lt;0. 05) . The NT3 and NT4 levels had no significant difference in all groups. The expressions of NGF and BDNF were positively related to the expressions of synaptophysin( r1 = 0. 892, r2 = 0. 995, P lt; 0. 05) and neurofilament( r1 = 0. 949, r2 =0. 936, P lt;0. 05) , also positively related to the airway hyperresponsiveness ( r1 =0. 929, r2 = 0. 910, P lt; 0. 05) . Conclusion RSV infection results in increased expressions of NGF and BDNF in the lung, which are correlated to the change of airway neural plasticity and airway hyperresponsiveness.
Objective To explore the profile and diagnosis value of airway resistances before and after bronchial dilation test ( BDT) in patients with COPD and asthma. Methods Airway resistances before and after BDT were measured in COPD patients and asthma patients with different severity by impulse oscillometry ( IOS) , and the characteristic changes of the two different diseases were analyzed compared with healthy subjects. Results Airway resistance indexes except X5 were higher in the COPD and the asthma patients than those in the healthy subjects before BDT ( P lt; 0. 05) . There were significant differences in airway resistance indexes except X5 and Rc between the mild asthma patients and the moderate to severe asthma patients. Significant difference in Z5, Fres, and Rp were observed in the mild COPD patientscompared with the moderate to severe COPD patients. There were statistical differences in airway resistance indexes except X5 between the two groups before and after BDT both in the COPD and the asthma patients ( P lt;0. 05) . The rates of change in Z5, Fres, R5, and Rp were higher than those of FEV1% pred, especially higher in the asthma patients than in the COPD patients ( P lt; 0. 05) . Significant negative correlations between FEV1% pred and Z5, Fres, R5, Rp were revealed in the COPD and the asthma patients ( P lt;0. 01) .The correlation between Fres and FEV1% pred was most significant in the COPD and the asthma patients ( r = - 0. 561, - 0. 761) . Conclusion Airway resistances measured by IOS is sensitive indicators in detecting the airflow obstruction in COPD and asthma, and is useful in early and differential diagnosis of COPD and asthma.