Effect of fumigation height and time on cryopreservation of ram semen.

The cooling rate is a crucial factor in the process of freezing semen, influencing the overall freezing effectiveness. The height and time of fumigation can significantly impact the rate of cooling. Appropriate cooling rates can help minimize the formation of ice crystals in spermatozoa and reduce potential damage to them. Therefore, the aim of this study was to evaluate the effect of different fumigation heights and time for the cryopreservation of Hu ram semen. Experiments I-IV assessed the effect of semen cryopreservation by testing the post-thawed spermatozoa total motility (TM), progressive motility (PM) and kinetic parameters fumigated at distances of 2, 4, 6 and 8 cm for durations of 5, 10, 15 and 20 min, respectively. Based on the results of experiments I to IV, experiment V evaluated the effect of semen cryopreservation by testing the post-thawed spermatozoa TM, PM, kinetic parameters, plasma membrane integrity, acrosome integrity and reactive oxygen species (ROS) level fumigated at distances of 2, 4, 6 and 8 cm for duration of 20 min. The results indicated that fumigation at 2 cm for 20 min significantly (P < 0.05) improved spermatozoa TM, PM, mean angular displacement (MAD), plasma membrane integrity and acrosome integrity compared to other groups. Additionally, it significantly (P < 0.05) reduced spermatozoa ROS level compared to the 6 and 8 cm groups. In conclusion, fumigation for 20 min at a distance of 2 cm from the liquid nitrogen surface is the most suitable cooling method for the cryopreservation of Hu ram semen.

Effect of Different Dilution Methods and Ratios of Ram Semen on Sperm Parameters after Cryopreservation.

The dilution method and ratio were tested to assess their effects on the Hu ram semen after cryopreservation. Experiment I aimed to explore the effect of various dilution ratios (1:1, 1:2, 1:3, 1:4) of diluent I (Tris-based and egg yolk) under the condition of 1:1 dilution of diluent II (diluent I and glycerol) on the Hu ram semen preserved in liquid nitrogen regarding spermatozoa motility and kinetic parameters. Experiment II aimed to investigate the effect of various dilution ratios (1:1, 1:2, 1:3, 1:4) of diluent I under the condition of 1:2 dilution of diluent II to the Hu ram semen for cryopreservation on spermatozoa motility and kinetic parameters. The purpose of experiment III is to assess the effect of various dilution methods and ratios on the cryopreservation of Hu ram semen by detecting spermatozoa motility, kinetic parameters, plasma membrane integrity, acrosome integrity and reactive oxygen species (ROS) level. Experiment III includes four groups: one-step dilution method and two-step dilution method. The two-step dilution method includes two groups: 1:2, 1:1 and 1:3, 1:2, and the one-step dilution method includes two groups: 1:5 and 1:11. The results indicated that the post-thawed spermatozoa total motility (TM), progressive motility (PM) and average motion degree (MAD) were highest in the 1:2 group and significantly higher (p < 0.05) than those in the 1:1 and 1:4 groups under the condition of 1:1 dilution of diluent II. The post-thawed spermatozoa TM and PM of the 1:3 group were significantly higher (p < 0.05) than those of the other groups under the condition of 1:2 dilution of diluent II. The post-thawed spermatozoa TM, PM, plasma membrane integrity and acrosome integrity of the two-step group (1:3, 1:2) were the highest and significantly higher (p < 0.05) than those in the other groups. Additionally, the post-thawed spermatozoa ROS level of the two-step group (1:3, 1:2) was significantly lower (p < 0.05) than that in the one-step groups (1:5 and 1:11). Therefore, a two-step dilution (1:3, 1:2) was found to be the most suitable method and ratio for diluting the Hu ram semen after cryopreservation.

Astaxanthin Improved the Quality of Hu Ram Semen by Increasing the Antioxidant Capacity and Mitochondrial Potential and Mitigating Free Radicals-Induced Oxidative Damage.

The objective of this research was to investigate the effect of astaxanthin supplementations of semen extender on the quality of Hu ram semen after up to five days of preservation at 4 °C. Semen samples were collected from five healthy Hu rams using an artificial vagina during breeding season (April to August 2023) and diluted with a basic extender supplemented with control (0), 1 µM, 2 µM, 3.5 µM, or 4.5 µM of AXT. Overall, 170 semen ejaculate samples (34 repetitions) from five healthy Hu rams were used in our research study. The results revealed that the addition of AXT (3.5 µM) significantly (p ≤ 0.05) increased the sperm kinematic indexes (T.M%, P.M%, MAD%, STR%, and LIN %), sperm viability, plasma membrane integrity, acrosome integrity, total antioxidant content (T-AOC), and mitochondrial membrane potential (MMP) of the Hu rams spermatozoa after up to five days of preservation at 4 °C. Contrary to that, the addition of the best concentration of AXT (3.5 µM) to the semen extender significantly (p ≤ 0.05) reduced the reactive oxygen species (ROS) and malondialdehyde (MDA) concentration of Hu ram semen. In conclusion, the results of the current study indicate that the addition of a semen extender with AXT improves the quality of Hu ram spermatozoa by increasing the total antioxidant capacity (T-AOC) and mitochondrial membrane potential (MMP). On the other hand, reducing free radicals induced oxidative (ROS) and per oxidative (MDA) damage to Hu ram semen.

Punicalagin Protects Ram Sperm from Oxidative Stress by Enhancing Antioxidant Capacity and Mitochondrial Potential during Liquid Storage at 4 °C.

The aim of this study was to investigate the effect of punicalagin, an antioxidant, on ram sperm quality. Semen samples were collected and pooled from five rams, then diluted using a Tris-based diluent containing various concentrations (0, 5, 15, 30 and 45 µM) of punicalagin. Sperm motility, plasma membrane integrity, acrosome integrity, total antioxidant capacity (TAC), reactive oxygen species (ROS), malondialdehyde (MDA), mitochondrial membrane potential (MMP), superoxide dismutase (SOD) and catalase (CAT) were measured and analyzed during liquid storage at 4 °C. The results showed that the Tris-based solution containing punicalagin improved sperm motility, plasma membrane integrity, acrosome integrity, TAC, SOD, CAT and MMP, and decreased ROS content and MDA content. At the same time, the semen sample diluted with the Tris-based solution supplemented with 30 µM punicalagin achieved the best effect. The sperm total motility, progressive motility, plasma membrane integrity, acrosome integrity, TAC, SOD, CAT and MMP of the group supplemented with 30 µM punicalagin were significantly (p < 0.05) higher than those of the other groups on the 5th day during the liquid storage at 4 °C. Meanwhile, the ROS content and MDA content were significantly (p < 0.05) lower than those in the other groups. In conclusion, the optimal concentration of punicalagin in the Hu ram semen diluent was determined to be 30 µM. The results indicated that a diluent supplemented with punicalagin could enhance the quality of ram sperm preserved at 4 °C by increasing antioxidant capacity, mitochondrial potential and reducing oxidative stress.

Alpha-lipoic acid improves the quality of ram spermatozoa stored at 4°C by reducing oxidative stress and increasing mitochondrial potential.

Introduction: Ram spermatozoa inevitably produce a large number of reactive oxygen species (ROS) during liquid storage, leading to oxidative stress and a decline of spermatozoa quality. Therefore, it is particularly important to add exogenous antioxidants during the process of semen liquid preservation. The purpose of this study is to investigate whether adding alpha-lipoic acid (ALA) to ram semen can reduce oxidative stress and enhance spermatozoa quality during the liquid storage at 4°C. Methods: Different concentrations of ALA (0, 0.025, 0.05, 0.1, 0.5, 1 mM) were added to semen and stored at 4°C. During storage at 4°C, spermatozoa motility, kinetic parameters, membrane integrity, acrosome integrity, energy metabolism parameters (mitochondrial membrane potential (ΔΨM) and adenosine triphosphate (ATP)) and oxidative stress parameters [ROS, malondialdehyde (MDA), total antioxidant capacity (TAC), superoxide dismutase (SOD)] were assessed. Results and discussion: The results indicated that 0.1 mM ALA significantly (p<0.05) improved spermatozoa total motility (TM) and progressive motility (PM), plasma membrane integrity, acrosome integrity, ΔΨM, ATP, TAC, and SOD, while significantly (p<0.05) reducing spermatozoa ROS and MDA content compared to the control group. In conclusion, ALA can reduce damage caused by oxidative stress in spermatozoa and effectively improve the quality of semen preserved at 4°C. And the optimal concentration is 0.1 mM.

Systematic review and meta-analysis of the efficacy of N-acetylcysteine in the treatment of acute exacerbation of chronic obstructive pulmonary disease.

BACKGROUND: Whether N-acetylcysteine (NAC) therapy can promote the improvement of clinical symptoms and lung function in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) has not been verified by large-scale randomized controlled trials, only a few small sample studies. METHODS: English databases were searched using a combination of the following terms: "chronic obstructive pulmonary disease", "acute exacerbation of chronic obstructive pulmonary disease", and "N-acetylcysteine". Studies examining NAC in the treatment of AECOPD were screened, so as to be a reference for the experimental group. Meta-analysis was performed using RevMan 5.3 software (Cochrane, Northern Europe), with a total of 15 included literatures. RESULTS: The heterogeneity test of improvement rate showed Chi2=1.89, df=7, I2=0% <50%, and P=0.97 (>0.01); the risk rate was 1.09, the 95% confidence interval (CI) was (1.04-1.14), Z=3.93, and P<0.0001. The heterogeneity test of forced expiratory volume in the first second (FEV1) showed that Tau2=63.39, Chi2=118.66, df=9, I2=92% >50%, and P=0.88 (<0.0001); the mean difference was 30.63 (95% CI: 25.48-35.78), Z=11.65, and P<0.0001. The results of the heterogeneity test of forced expiratory volume in the first second/forced vital capacity (FEV1/FVC) showed that Tau2=60.03, Chi2=74.09, df=5, I2=93% >50%, and P<0.0001; the mean difference was 30.42 (95% CI: 24.00-36.85), Z=9.28, and P<0.0001. The heterogeneity test for glutathione sulfur transferase (GSH-ST) activity showed that Tau2=4.12, Chi2=58.12, df=5, I2=91% >50%, and P<0.0001; the mean difference was 3.10 (95% CI: 1.38-4.82), Z=3.63, and P=0.0004. CONCLUSIONS: Our meta-analysis confirmed that NAC could promote the symptom improvement rate of patients with AECOPD, improve lung function in FEV1 and FEV1/FVC, and enhance the body's antioxidant capacity.

Clinical Research on Prognostic Evaluation of Subjects With IPF by Peripheral Blood Biomarkers, Quantitative Imaging Characteristics and Pulmonary Function Parameters / Estudio clínico sobre la evaluación pronóstica de sujetos con FPI mediante biomarcadores en sangre periférica, características cuantitativas en las pruebas de imagen y los parámetros de función pulmonar

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is an irreversible and progressive fatal interstitial lung disease with a poor prognosis. The aim of this study is to investigate the predictive value of combined blood biomarkers, pulmonary function and quantitative monitoring by computer-aided diagnosis (CAD) system in IPF patients. METHODS: Pulmonary baseline function and pathological features of 126 patients with IPF were analyzed using spirometry and chest X-ray. Patients were divided into survival group and non-survival group after 5 years follow-up. The relationships the levels of peripheral blood biomarkers, quantitative imaging characteristics and pulmonary function were analyzed between the two groups. RESULTS: The baseline level of serum Krebs von den Lungen-6 (KL-6) and C-X-C motif chemokine 13 (CXCL13) were moderately or highly correlated with annual changes in forced vital capacity (FVC), carbon monoxide diffusing capacity (DLCO), total lung capacity (TLC), total interstitial lung disease (ILD) lesions, and the volume changes of reticular. The baseline level of serum KL-6 was higher than the cut-off value of 800.0 U/ml and baseline level of serum CXCL13 was higher than the cut-off value of 62.0 pg/ml. IPF patients with baseline levels of serum KL-6 and CXCL13 lower than the cut-off value had longer median survival time. CONCLUSIONS: Serum KL-6 and CXCL13 may be predictive biomarkers for the outcomes of patients with IPF patients and their baseline levels were related to the progression of pulmonary function and quantitative monitoring by CAD system

INTRODUCCIÓN: La fibrosis pulmonar idiopática (FPI) es una enfermedad intersticial pulmonar irreversible, progresiva y mortal con mal pronóstico. El objetivo de este estudio es investigar el valor predictivo combinado de los marcadores en sangre, la función pulmonar y el seguimiento cuantitativo mediante sistemas de diagnóstico asistido por ordenador (DAO) en pacientes con FPI. MÉTODOS: Se analizaron la función inicial pulmonar y los criterios patológicos de 126 pacientes con FPI mediante espirometría y radiografía de tórax. Los pacientes se dividieron en grupo de supervivencia y grupo de no supervivencia a los 5años de seguimiento. Se comparó la relación entre los niveles de marcadores en sangre periférica, las características cuantitativas en la prueba de imagen y la función pulmonar entre ambos grupos. RESULTADOS: Los niveles iniciales de Krebs von den Lungen-6 (KL-6) y la quimiocina de motivo CXC 13 (CXCL13) en suero se correlacionaron moderada o fuertemente con los cambios anuales en la capacidad vital forzada (FVC), la capacidad de difusión de monóxido de carbono (DLCO), la capacidad pulmonar total (TLC), el total de las lesiones de enfermedad pulmonar intersticial (EPI) y cambios en el volumen de densidades reticulares. El nivel basal de KL-6 en suero fue mayor que el valor de corte de 800 U/ml y el nivel basal de CXCL13 en suero fue mayor que el valor de corte de 62 pg/ml. Los pacientes con FPI y niveles iniciales en suero de KL-6 y CXCL13 más bajos que el valor de punto de corte presentaron una mediana mayor de tiempo de supervivencia. CONCLUSIONES: Los valores en suero de KL-6 y CXCL13 podrían servir como biomarcadores predictivos para el pronóstico de los pacientes con FPI. Sus niveles al inicio del estudio se relacionaron con la progresión de la función pulmonar y el seguimiento cuantitativo con el sistema DAO

Clinical Research on Prognostic Evaluation of Subjects With IPF by Peripheral Blood Biomarkers, Quantitative Imaging Characteristics and Pulmonary Function Parameters.

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is an irreversible and progressive fatal interstitial lung disease with a poor prognosis. The aim of this study is to investigate the predictive value of combined blood biomarkers, pulmonary function and quantitative monitoring by computer-aided diagnosis (CAD) system in IPF patients. METHODS: Pulmonary baseline function and pathological features of 126 patients with IPF were analyzed using spirometry and chest X-ray. Patients were divided into survival group and non-survival group after 5 years follow-up. The relationships the levels of peripheral blood biomarkers, quantitative imaging characteristics and pulmonary function were analyzed between the two groups. RESULTS: The baseline level of serum Krebs von den Lungen-6 (KL-6) and C-X-C motif chemokine 13 (CXCL13) were moderately or highly correlated with annual changes in forced vital capacity (FVC), carbon monoxide diffusing capacity (DLCO), total lung capacity (TLC), total interstitial lung disease (ILD) lesions, and the volume changes of reticular. The baseline level of serum KL-6 was higher than the cut-off value of 800.0U/ml and baseline level of serum CXCL13 was higher than the cut-off value of 62.0pg/ml. IPF patients with baseline levels of serum KL-6 and CXCL13 lower than the cut-off value had longer median survival time. CONCLUSIONS: Serum KL-6 and CXCL13 may be predictive biomarkers for the outcomes of patients with IPF patients and their baseline levels were related to the progression of pulmonary function and quantitative monitoring by CAD system.

Silencing of LncRNA-HOTAIR decreases drug resistance of Non-Small Cell Lung Cancer cells by inactivating autophagy via suppressing the phosphorylation of ULK1.

Drug resistance is an important factor leading to the recurrence and metastasis of Non-Small Cell Lung Cancer (NSCLC). Long non-coding RNAs (LncRNAs) play important roles in drug resistance of tumor cells. The aim of our study was to investigate the mechanism of LncRNA-HOTAIR in regulating drug resistance of NSCLC cells. Our data indicated that HOTAIR was overexpressed in NSCLC cell lines. Silencing of HOTAIR decreased cell proliferation and increased apoptosis of NSCLC cells (A549). Besides that, HOTAIR shRNA transfection suppressed drug resistance of A549 cells to Crizotinib by more effectively inhibiting cell viability and promoting apoptosis compared with HOTAIR scramble group. Moreover, silencing of HOTAIR decreased the number of LC3+ puncta and the expression of Beclin1, p-ULK1 and the ratio of LC3 II/I/in Crizotinib treated A549 cells, indicating that silencing of HOTAIR decreased drug resistance of NSCLC cells might through inhibiting autophagy via the ULK1 pathway. In order to further prove our conclusion, Rapamycin (Rapa), an autophagy inducer, was used in our study. With the adjunction of Rapa, obvious autophagy was induced by increasing the number of LC3+ puncta, the ratio of LC3 II/I and the expression of p-ULK1 compared with Crizotinib + HOTAIR shRNA group. What is more, the activation of autophagy abolished the effect of HOTAIR shRNA on decreasing drug resistance by increasing cell viability and decreasing cell apoptosis. These results supported our conclusion that silencing of HOTAIR decreased drug resistance of NSCLC cells to Crizotinib through inhibition of autophagy via suppressing phosphorylation of ULK1.

Long Noncoding RNA (lncRNA) HOTAIR Affects Tumorigenesis and Metastasis of Non-Small Cell Lung Cancer by Upregulating miR-613.

Non-small cell lung cancer (NSCLC) is one of the most deadly cancers with poor prognosis. Recent findings suggested that the lncRNA HOTAIR played an important role in tumorigenesis and metastasis. In the present study, HOTAIR was highly expressed in NSCLC tumor tissues and cell lines (H1299, H23, H292, and A549). Downregulation of HOTAIR suppressed cell proliferation and invasion, while it promoted apoptosis of NSCLC cells. The targeting relationship between HOTAIR and miR-613 was first revealed by bioinformatics prediction. miR-613 was found to be lowly expressed in NSCLC tumor tissues and cell lines. Knockdown of HOTAIR increased the expression of miR-613 significantly, and cotransfection with miR-613 inhibitor reversed this increase, indicating that the expression of miR-613 was negatively regulated by HOTAIR. The targeting relationship between HOTAIR and miR-613 was further confirmed through the luciferase report assay. Moreover, the cotransfection of HOTAIR shRNA and miR-613 inhibitor counteracted the tumor inhibition effects of HOTAIR shRNA through promoting cell proliferation and invasion while suppressing apoptosis in NSCLC cells, suggesting that the HOTAIR/miR-613 axis was involved in tumorigenesis and metastasis of NSCLC. In vivo experiments revealed that knockdown of HOTAIR decreased tumor growth and invasion and increased apoptosis and miR-613 expression. In conclusion, our study indicated that downregulation of HOTAIR suppressed tumorigenesis and metastasis of NSCLC via upregulating the expression of miR-613. The HOTAIR/miR-613 axis might provide a new potential therapeutic strategy for NSCLC treatment.

Responsiveness to methacholine, but not leukotriene D4, correlates with fractional exhaled nitric oxide in asthma.

BACKGROUND AND AIMS: Correlation between fractional exhaled nitric oxide (FeNO) and responsiveness to inhaled leukotriene D4 (LTD4 ) and methacholine (MCh) might be different. This study aims to determine the correlation between FeNO and airway responsiveness to LTD4 and MCh, and to compare the airway responsiveness to inhaled LTD4 and MCh and FeNO in non-smokers, patients without rhinitis and non-smokers without rhinitis. METHODS: In this cross-over study, asthmatic patients and healthy subjects underwent LTD4 and MCh inhalation challenge at a 2- to 14-day interval. The FeNO was measured by using NIOX MINO, a portable instrument, at the initial visit, before spirometry and inhalation challenge tests. Subgroup analyses were performed in asthmatic patients based on the categorisation of never-smoker group, non-rhinitis group and never-smoker without rhinitis group. RESULTS: Of 62 asthmatic patients enrolled, 43 did not have self-reported rhinitis (asthmatic patients without rhinitis), 56 were never-smokers (asthmatic non-smokers), giving rise to 37 non-smokers who did not have rhinitis (asthmatic non-smokers without rhinitis). Twenty-one healthy subjects were enrolled. Overall, Log10 FeNO correlated with Log10 PD20 FEV1 -MCh but not Log10 PD20 FEV1 -LTD4 or Log10 (LTD4 /MCh potency ratio). Reduced FeNO was associated with significantly higher Log10 PD20 FEV1 -MCh but not Log10 PD20 FEV1 -LTD4 , except for non-smokers. Compared with all asthmatic patients, asthmatic non-smokers without rhinitis were characterised by markedly reduced levels of Log10 PD20 FEV1 -MCh but not Log10 PD20 FEV1 -LTD4 . The difference in all parameters did not reach statistical significance among asthmatic patients without rhinitis, asthmatic non-smokers and asthmatic non-smokers without rhinitis. CONCLUSION: FeNO correlates with airway responsiveness to inhaled MCh but not LTD4 , in asthmatic patients, particularly in asthmatic non-smokers without rhinitis.

Leukotriene D4 inhalation challenge for predicting short-term efficacy of montelukast: a pilot study.

INTRODUCTION: The convenient measure to predict efficacy of leukotriene receptor antagonist is lacking. OBJECTIVES: To determine if leukotriene D4 inhalation challenge predicts short-term efficacy of montelukast in asthma. METHODS: In this open-labelled 28-day trial, 45 patients with asthma were allocated to leukotriene-sensitive and leukotriene-insensitive group to receive montelukast monotherapy (10 mg, once daily) based on the positive threshold of leukotriene D4 inhalation challenge test (4.800 nmol). Miscellaneous measurements comprised fractional exhaled nitric oxide, methacholine inhalation challenge, Asthma Control Test and Asthma Quality of Life Questionnaire. Peak expiratory flow was self-monitored throughout the treatment. End point assessments were performed 3 to 5 days after montelukast withdrawal. RESULTS: Twenty-three patients in leukotriene-sensitive group and 10 leukotriene-insensitive group completed the study. Both groups differed neither in 28-day peak expiratory flow rate nor in maximal weekly peak expiratory flow (both P > 0.05). However, minimal weekly peak expiratory flow was significantly higher in leukotriene-insensitive group throughout the treatment course (all P < 0.05) except for week 1 (P > 0.05). Both groups did not differ statistically in the post-treatment improvement in forced expiratory volume in 1 s (FEV1 ) predicted% prior to inhalation challenge, fractional exhaled nitric oxide or the airway responsiveness to leukotriene D4 or methacholine (all P > 0.05). There was a marked increase in Asthma Control Test score and the symptom score of Asthma Quality of Life Questionnaire in both groups (both P < 0.05). The overall significance of Logistic regression model was unremarkable (P = 0.467). CONCLUSION: Responsiveness to inhaled leukotriene D4 alone might not be sufficient to predict the short-term efficacy of montelukast monotherapy in patients with asthma.

Response--dose ratio is a surrogate of cumulative provocative dosage for bronchial provocation tests in asthma.

BACKGROUND: Response-dose ratio (RDR) and cumulative provocative dosage (PD) are useful indices reflecting airway responsiveness in asthma. OBJECTIVES: To compare the diagnostic value of RDR and PD, by conducting leukotriene D4 (LTD4-BPT) and methacholine bronchial provocation test (MCh-BPT), in different asthma control levels. METHODS: Healthy subjects and asthmatic patients underwent LTD4-BPT and MCh-BPT, at 2-14-day interval. This entailed assessment of the distribution characteristics, correlation, and diagnostic value of PD inducing 20% fall in forced expiratory volume in one second (PD20FEV1) and the RDR, defined as FEV1 fall (%) at the final step divided by the corresponding provocative dosage. RESULTS: Twenty uncontrolled, 22 partly controlled, 20 controlled asthmatics, and 21 healthy subjects were enrolled. Log10RDR was positively correlated with log10PD20FEV1 in both BPTs (all P < 0.05). Poorer asthma control was associated with significantly lower PD20FEV1 and higher RDR (both P < 0.05). The differences in PD20FEV1 and RDR between partly controlled and controlled asthma were unremarkable (both P > 0.05). Compared with log10PD20FEV1, the log10RDR yielded similar diagnostic values in both BPTs. A lower percentile of RDR (≤ 25th percentile) was associated with higher baseline FEV1 (P < 0.05) and an increased proportion of well-controlled asthmatic patients. The combination of RDR and PD20FEV1 led to an increased diagnostic value compared with either parameter alone. CONCLUSIONS: RDR is a surrogate of PD20FEV1 for BPTs in asthma. This finding was not modified by different asthma control levels or the types of bronchoprovocants.

[Single-breath and rebreathing methods for measurement of pulmonary diffusing function: a comparative study].

OBJECTIVE: To compare the difference of pulmonary diffusing capacity measured by single-breath (SB) and re-breathing (RB) in normal subjects, patients with interstitial lung disease (ILD) and chronic obstructive pulmonary disease (COPD). METHODS: We enrolled a cohort of subjects from the Guangzhou Institute of Respiratory Disease between September 2011 and February 2012: control group 29 (male 9, female 20, 42-74 y), ILD group 32 (male 15, female 17, 41-72 y), COPD group 32 (male 28, female 4, 40-75 y). All subjects underwent pulmonary diffusing capacity test using SB or RB method according to random figures order list. Diffusing capacity of carbon monoxide per predicted measured by SB method (SB-DLCO%pred) of the normal group was used as the standard to adjust the diffusing capacity of carbon monoxide per predicted measured by RB method (RB-DLCO%pred) and diffusing capacity of carbon monoxide per liter of VA per predicted measured by RB (RB-DLCO/VA%pred) in the 3 groups, respectively. Comparisons between 2 groups were performed by using the independent-sample t test, among more than 2 groups by using the One-Way ANOVA test, while the ROC curve was used to calculate the area under curve (AUC) and its 95%CI. RESULTS: In the control group, 15 subjects' RB-DLCO%pred was lower than 80%, and the mean value (78.8 ± 2.1)% was also lower than 80%. Using SB-DLCO%pred of the normal group as a standard to adjust the RB-DLCO%pred, the corrected value was 1.097, and then this value was used to adjust RB-DLCO/VA%pred in the 3 groups, respectively. Before correction DLCO%pred [the control group: (91.2 ± 1.9)% vs (78.8 ± 2.1)%; the ILD group: (45.8 ± 2.6)% vs (60.0 ± 1.9)%;the COPD group: (66.3 ± 2.9)% vs (56.6 ± 1.6)%]and DLCO/VA%pred [the control group: (99.8 ± 2.3)% vs (84.6 ± 4.5)%; the ILD group: (75.9 ± 3.0)% vs (88.5 ± 5.4)%; the COPD group: (80.2 ± 3.7)% vs (50.6 ± 2.5)% ] between the SB and RB were statistically different among the 3 groups. After correction, only the DLCO%pred [(45.8 ± 2.6)% vs (65.8 ± 2.1)%], DLCO/VA%pred [ (75.9 ± 3.0)% vs (102.2 ± 6.2)%] of the ILD group and the DLCO/VA%pred [(80.2 ± 3.7) vs (58.3 ± 2.8)%] of the COPD group had significant difference between the 2 methods (t = -6.00-4.68, all P < 0.01) . The test time of re-breathing in the COPD group (106 ± 5) s was significant longer than that of the ILD group (73 ± 4) s and the control group (79 ± 5) s (F = 11.99, P < 0.01), and the correlation between DLCO/VA%pred and the test time(r = -0.661, P < 0.01) was higher than the relationship between DLCO%pred and the test time (r = -0.391, P < 0.01). Furthermore, in the ILD group, the area of RB-DLCO%pred under ROC was 0.893, 95%CI being 0.817-0.970. In the COPD group, the area of RB-DLCO/VA%pred under ROC was 0.895, 95%CI being 0.811-0.979. CONCLUSIONS: There were differences between re-breathing and single-breath in measuring diffusing capacity. The present predicted value of the re-breathing method needed further study to confirm its applicability. Re-breathing method was more consistent with the respiratory physiology, and might be a better method to detect diseased states.

Responsiveness to leukotriene D4 and methacholine for predicting efficacy of montelukast in asthma.

A lower responsiveness to leukotriene D4 (LTD4) or higher LTD4/[methacholine (MCh)] potency ratio might suggest preferable outcomes of short-term montelukast monotherapy in terms of airway inflammation and lung function in asthmatic patients.

Leukotriene D4 and methacholine bronchial provocation tests for identifying leukotriene-responsiveness subtypes.

BACKGROUND: Both leukotriene D(4) (LTD(4)) and methacholine bronchial provocation tests are measurements of airway responsiveness; however, their correlation and distinction remain unexplored. OBJECTIVES: We sought to compare the 2 tests and classify leukotriene-responsiveness subtypes in asthmatic patients. METHODS: In this randomized cross-over study we enrolled healthy subjects and asthmatic patients with different control statuses. All subjects underwent both tests with a 2- to 14-day interval. Distribution and correlation of cumulative doses inducing a 20% decrease in FEV(1), LTD(4)/methacholine potency ratio, diagnostic value, and adverse events were recorded and analyzed. Asthmatic patients with a lower cumulative dose for LTD(4) and a higher leukotriene/methacholine potency ratio than geometric means were regarded as leukotriene responsive. RESULTS: Twenty patients with uncontrolled, 22 with partly controlled, and 20 with controlled asthma and 21 healthy subjects were enrolled. Geometric means of cumulative doses for LTD(4) and methacholine (0.272 nmol vs 0.945 µmol) were lowest in patients with uncontrolled asthma, followed by those with partly controlled (0.387 nmol vs 1.933 µmol) and controlled (1.484 nmol vs 3.946 µmol) asthma. The average potency ratio was highest in those with partly controlled asthma (5000.2), followed by those with uncontrolled (3477.7) and controlled (2702.6) asthma. Eighteen leukotriene-responsive asthmatic patients (29.03%) with a cumulative dose of LTD(4) of 0.533 nmol or less and a potency ratio of 3647 or greater were identified. Adverse events, including tachypnea and chest tightness, were similar and mild. No serious adverse event was reported. CONCLUSION: Diagnostic value and safety were ideal in both tests. The combination of cumulative dose for LTD(4) and potency ratio might be useful to identify leukotriene-responsive asthmatic patients.

Leukotriene D4 bronchial provocation test: methodology and diagnostic value.

BACKGROUND: Although leukotriene D4 (LTD4) is a potent bronchoconstrictor, little is known about airway responsiveness to LTD4 in asthmatics with different inflammation phenotypes. OBJECTIVES: To establish the methodology and investigate the distribution characters of airway responsiveness, diagnostic value and safety of LTD4 bronchial provocation test. METHODS: LTD4 bronchial provocation tests were performed in 62 asthmatics and 21 normal controls. Airway responsiveness was assessed based on the cumulative dosage causing a 20% fall in FEV(1) (PD(20)FEV(1)-LTD4) and was expressed as (median, interquartile range). The fall in spirometric parameters was plotted showing the distribution characters. The diagnostic value was assessed using receiver operation characteristic (ROC) curve. All adverse events were recorded during the test. RESULTS: Airway responsiveness to LTD4 was significantly higher in asthmatics (0.410 nmol, 0.808 nmol) as compared with normal controls (5.00 nmol, 0.00 nmol). The decrease in spirometric parameters varied after bronchoprovocation, which was negatively correlated with PD(20)FEV(1)-LTD4, among which FEV(1) had a maximal slope (r = -0.524, P = 0.000). High diagnostic value (AUC: 0.914, 95%CI: [0.855, 0.974]) was revealed by ROC curve. The major adverse events were dyspnea (82.3%), chest tightness (72.6%), wheezing (32.3%) and coughing (25.8%) in asthmatics, which could overall be recovered within 15.0 minutes after inhalation of 200 ∼ 400 mcg salbutamol MDI. No serious adverse event was reported. CONCLUSION: The established procedure of LTD4 bronchial provocation test is effective in the diagnosis of asthma and is well tolerated. Future studies are necessary to provide more evidences in terms of safety and efficacy. This may be helpful upon further application in clinical practice.