Objective To investigate the relationship of small airway function with airway sensitivity and reactivity and assess the factors influencingairway hyperresponsiveness (AHR).Methods Data of consecutive subjects with suspected asthma who had a≥20% reduction in FEV1 after ≤12.8 mmol/L cumulative doses of methacholine were analyzed from January 2005 to April 2006.Airway sensitivity was assessed by the cumulative dose of methacholine required to cause 20% reduction in FEV1 (PD20).Airway reactivity was analyzed using the slope of the dose-response curve (DRS).The DRS was defined as the reduction in FEV1 from baseline after the final dose of methacholine inhaled divided by the cumulative dose inhaled.Because of their highly skewed distribution，DRS was logarithmically transformed (log10) for all analysis.Results A total of 184 consecutive subjects aged 16 to 80 years was enrolled.There were 70 male (38.0%) and 114 female (62.0%) subjects.Subjects with higher airway sensitivity，indicated by lower PD20，also had a lower Vmax50% and Vmax25%，and vise versa.PD20 was negatively correlated wit log10DRS (r=-0.874，Plt;0.01).In a simple linear regression model，log10DNS was significantly correlated with FEV1%，Vmax50% or Vmax25% respectively (the determinant r2 were 0.062，0.097 and 0.085，respectively，all Plt;0.01).In a multiple linear regression model that included age，height，and percentage of predicted FEV1，Vmax50% and Vmax25% accounted for 3.9% and 2.6%，respectively，of variability in airway reactivity.The association between Vmax50% and log10DNS was significant in both male and female subjects.The r2 was higher in male subjects.The subjects were divided into three age groups and the association between Vmax50% or Vmax25% and log10DNS was higher in female than in male for age≤25 years，higher in male than in female for 25 -45 years.No association was found for agegt;45 years in both males and females.Conclusions Impaired small airway function is associated with higher airway sensitivity and reactivity to methacholine in subjects with suspected asthma.
ObjectiveTo evaluate the value of stroke volume variation (SVV) and intrathoracic blood volume index (ITBVI) to predict fluid responsiveness in mechanically ventilated septic shock patients with spontaneous breathing. MethodsA prospective observational study was conducted in the Department of Critical Care Medicine of the First Affiliated Hospital of Guangzhou Medical University. Fluid resuscitation data was collected in septic shock patients who received PiCCO monitoring from June 2013 to June 2014. Transpulmonary thermodilution data were collected before and after fluid resuscitation, including cardiac index (CI), SVV, ITBVI, and central venous pressure (CVP). Seventeen patients were defined as responders by an observed increase of≥15% in the cardiac index (CI) after fluid resuscitation, 12 patients were defined as non-responders. Pearson correlation between changes of CI (ΔCI) and SVV, ITBVI, CVP was established. Area under the receiver operating characteristic (ROC) curve of SVV, ITBVI and CVP was calculated for predicting fluid responsiveness. ResultsBaseline CI and ITBVI were significantly lower in the responders (P < 0.05).There was no significant difference in baseline SVV between the responders and the non-responders (P > 0.05). A significant correlation was found between baseline ITBVI andΔCI (r=-0.593, P < 0.001), but no significant correlation between SVV andΔCI (r=0.037, P=0.847) or CVP andΔCI (r=0.198, P=0.302). The area under ROC curve of SVV, ITBVI and SVV for predicting fluid responsiveness was 0.640 (P=0.207), 0.865 (P=0.001), and 0.463 (P=0.565), respectively. The cut-off value of ITBVI for predicting fluid responsiveness was 784 mL/m2 with a sensitivity of 100.0% and a specificity of 70.6%. ConclusionIn mechanically ventilated septic shock patients with spontaneous breathing, ITBVI may be a valuable indicator in predicting fluid responsiveness compared with SVV.
ObjectiveTo analyze responsiveness of Chinese version of Neck Outcome Score (NOOS-C) and provide a reliable measure to assess intervention effect for patients with neck pain.MethodsCross-cultural adaptation of NOOS was performed according to the Beaton’s guidelines for cross-cultural adaptation of self-report measures. Eighty patients with neck pain were recruited between September 2016 and May 2017. Those patients were assessed using NOOS-C and Chinese version of Neck Disability Index (NDI) before and after intervention. And 71 patients completed those questionnaires. The statistic differences of the score of each subscale and the total scale before and after intervention were evaluated by paired-samples t test. Internal responsiveness was determined by effect size (ES) and standardized response mean (SRM) based on the calculated difference before and after intervention. External responsiveness was analyzed by Spearman correlation coefficient.ResultsThe differences in symptom subscale, sleep disturbance subscale, participating in everyday life subscale, every day activity and pain subscale, and the scale between before and after intervention were significant (P<0.05) except for mobility subscale (P>0.05). The difference of NDI-C before and after intervention was –12.11%±17.45%, ES was 0.77, and SRM was 0.69. The difference of NOOS-C before and after intervention was 13.74±17.22, ES was 0.83, and SRM was 0.80. Spearman correlation analysis revealed that the relativity about NOOS-C and NDI-C before and after intervention were both negative (r=–0.914, P=0.000; r=–0.872, P=0.000).ConclusionNOOS-C’s responsiveness is good.
To diminish the specific lymphocytes that responsive to the rejection of allograft. Anti-rat CD4,CD8 monoclonal antibodies and trichosnthin (TCS) was conjugated to immunotoxin by heterobifunctional reagent SPDP, 2-IT. The free TCS was removed from conjugates mixture by a column of Sephacryl S-200. The SDS-PAGE and cytotoxic assay was used to measure the biological activity of immunotoxin. SDS-PAGE showed the immunotoxin, free McAb and TCS were in the mixture of conjugation, and the free TCS can be separated by Sephacryl S-200. In Vitro, the lymphocytes of rat can be killed by antiCD4,antiCD8 immunotoxin. The kill capability was relay to the amount of immunotoxin. The authors consider that the immunology unresponsiveness can be induced by antiCD4,antiCD8 immunotoxin. That was useful in induced transplantation tolerance.
Objective To analyze the quantitative relationship between respiratory effort and inferior vena cava (IVC) diameter variability in healthy adults, and explore the effects of respiratory effort on the fluid responsiveness with IVC diameter variability. Methods From October 2022 to May 2023, a cross-sectional study was conducted in healthy young subjects who met the criteria. Respiratory effort was evaluated by using portable pulmonary function to measure the subjects’ inspiratory conditions in three states (quiet breathing, moderate inspiration, and maximal inspiration). At the same time, the IVC internal diameter was measured by bedside ultrasound and the IVC diameter variability was calculated. The correlation between inspiratory volume and IVC diameter variation was analyzed, and the receiver operator characteristic (ROC) curve was drawn. The sensitivity and specificity of fluid responsiveness induced by inspiratory effort were predicted according to the area under the ROC curve (AUC). Results A total of 95 subjects were screened, aged 27.13±5.77 years, of whom 30 (32%) subjects were males. During quiet breathing, 41.1% of subjects had IVC inner diameter variation ≥50%. For moderate inspiration, it was 68.4%. At maximum inspiration, this proportion is more than 85%. Inspiratory volume was moderately positively correlated with IVC diameter variation, and the correlation coefficient r=0.45. With the IVC diameter variation ≥50% as the positive criterion for fluid responsiveness, the AUC of fluid responsiveness induced by inspiratory effort was 0.73 (95% confidence interval 0.67 - 0.78, P<0.001), and the inspiratory volume threshold was 13 mL/kg ideal body weight when the maximum Youden index was 0.41. That is, moderate force breathing can induce fluid responsiveness, with sensitivity of 79.57% and specificity of 61.62%. Conclusion The degree of respiratory effort significantly affects the IVC inner diameter variation, and there may be false positives in the evaluation of fluid responsiveness according to IVC inner diameter variation in the case of spontaneous breathing.
Objective To investigate the changes of small airway function and diffusing capacity in patients with mild asthma before and after bronchial provocation test (BPT).Methods BPT was performed in suspected asthma patients with chief complaints of paroxysmal wheeze,chest tightness and cough，but with normal chest X-ray and baseline pulmonary function.BPT positive group was regarded as asthma group，while BPT negative group as control group.Lung volume，ventilatory function and diffusing capacity were measured before and after BPT and compared between the asthma and control groups.Results （A）No statistical differences were found in FEV1%，FEV1/FVC，FVC%，VC%，TLC%，FRC%，RV%，RV/TLC between the asthma and control groups before BPT.FEV1/FVC and FVC% were significantly decreased (all Plt;0.01)，while FRC% (Plt;0.05)，RV% (Plt;0.01) and RV/TLC (Plt;0.01) increased significantly in the asthma group after BPT compared with the control group.The decline rate of FEV1/FVC and FVC% and the increase rate of TLC%，RV%，RV/TLC were significantly higher in the asthma group than those in the control group (all Plt;0.01).（B）Compared with the control group，FEF25%-75% (Plt;0.05)，Vmax75% (Plt;0.01) and Vmax50% (Plt;0.05) were significantly lowered before BPT，while the above parameters and Vmax25% were significantly decreased after BPT in the asthma group (all Plt;0.01).The decline rate of FEF25%-75%，Vmax75%，Vmax50% and Vmax25% was significantly higher in the asthma group than those in the control group (all Plt;0.01).（C）There was no statistical difference in DLCO in both groups before and after BPT.Conclusions Patients with mild asthma had small airways impairment before BCT which further declined after BPT.However,no impairment of diffusion capacity was found before or after BPT.
Objective To explore the relationship between obstructive sleep apnea hypopnea syndrome ( OSAHS) and airway hyperresponsiveness ( AHR) . Methods 197 subjects suspected for OSAHS were enrolled in the study. They were all performed overnight polysomnogram ( PSG) monitoring and lung function test. Acoording to the results of FEV1% pred, they were performed bronchial provocation test( BPT)or brochial dilation test( BDT) . The relation between apnea hypopnea index ( AHI) and the degree of airway hyperresponsiveness ( AHR, expressed as PD20 -FEV1 ) was evaluated by linear correlation analysis. Results 117 patients were diagnosed as OSAHS, in which 28 cases were complicated with AHR( 3 cases with positive BDT result, 25 cases with AHR) . In 80 non-OSAHS patients, 7 cases were complicated with AHR. Theincidence of AHR was higher in the OSAHS patients compared with the non-OSAHS patients( 23. 9% vs 8. 8% , P lt; 0. 01 ) . AHI of OSAHS patients with AHR was higher than OSAHS patients without AHR[ ( 30. 3 ±5. 1) /h vs ( 23. 7 ±2. 4) /h, P lt;0. 01] . There was a positive correlation between AHI and degree of AHR in OSAHS patients with AHR( r=0. 62, P lt;0. 05, n=25) . Conclusion OSAHS is associated with an increased risk of AHR.
Objective To study the responsiveness change of neutrophils when experiencing the second insult after the initial temperature activation in cardiopulmonary bypass (CPB) by using an in vitro model. Methods The neutrophils were isolated from blood which was drawn from each of 60 health volunteers. The samples were divided into 5 groups including normothermia, tepid temperature, moderate hypothermia, deep hypothermia, and rewarming hyperthermia by random digital table with 12 in each group according to the change of temperature during CPB. An in vitro model for studying neutrophil responsiveness was established by using a polymerase chain reaction thermocycler. Five time points were set for each group, including T0: starting CPB, T1: starting rewarming, T2: 0.5 h after rewarming, T3: 1 h after rewarming, and T4: 1.5 h after rewarming. Platelet activating factor (PAF) was added into each group at T2, T3, and T4, and then the value of membranebound elastase (MBE) activity was measured as responsiveness of neutrophils. Analysis of covariance was applied by using SPSS 13.0 for statistic analysis. If the [CM(159mm]covariance had significant difference between main effects, Bonferroni method would be applied for pairwise comparison. Results The main effect difference of neutrophil responsiveness among different groups was statistically different (F=4.372,P=0.002). MBE value had no statistical difference between the normothermia and tepid temperature groups (81.9±4.5 ng/10.6 cells vs. 76.5±3.6 ng/106 cells, P=0.134). while the MBE values in these two groups were higher than those in the other three groups (P=0.001). MBE value in the rewarming hyperthermia group was higher than that in the deep hypothermia group (61.2±2.7 ng/106 cells vs. 50.9±3.7 ng/106 cells, P=0.005). There was no statistical difference between the moderate hypothermia group (56.4±3.2 ng/106 cells) and the rewarming hyperthermia group (P=0.167), so was it between the moderate hypothermia group and the deep hypothermia group (P=0.107). The main effects of neutrophil responsiveness at different time points was statistically different (F=3.566, P=0.03) when PAF was added. MBE value at T4 was higher thanthat at T2 (70.9±2.5 ng/106 cells vs. 59.9±2.3 ng/106 cells, P=0.027). There was no statistical difference among T3 (65.5±1.8 ng/106 cells), T2 (P=0.168), and T4 (P=0.292) in MBE value. Conclusion Normothermia， tepid temperature， and rewarming hyperthermia during CPB can enhance neutrophil responsiveness and MBE release when neutrophils suffer the second insult. There is a time window for neutrophils to be easily activated during rewarming period.
ObjectiveTo explore the effects of Aspergillus fumigatus (A. fumigatus) on airway inflammation, airway responsiveness and total serum IgE in asthmatic rats. MethodsEighteen male Wistar rats were divided into three groups randomly, ie. a normal control group, an asthmatic model group, and an A. fumigatus group. The rats in the model group and the A.fumigatus group were sensititized and challenged with ovalbumin to establish asthmatic model. After establishment of asthmatic model, the rats in the A. fumigatus group were treated with chronic A. fumigatus spores inhalation. Subsequently, airway responsiveness/sensitivity to methacholine(Ach), levels of serum IgE and airway inflammation were assessed and compared among three groups. ResultsCompared with the asthmatic rats, the rats treated with A. fumigatus showed higher airway responsiveness (Penh/baselin value was significantly increased at the Mch concentration of 12.5, 25 and 50 mg/mL), increased inflammatory cells infiltration in pulmonary tissue slices and increased serum IgE level (P < 0.05). Most importantly, serum IgE level was detected in close relationship with PC100 which was defined as the dose of Mch causing 100% increase of enhance pause (Penh) value without Mch challenge (r=-0.873, P < 0.01). Serum IgE level was also closely related to the percentage of eosinophils in bronchoalveolar lavage fluid (r=0.937, P < 0.01). ConclusionsChronic A. fumigatus inhalation aggravates airway inflammation, bronchial hyperresponsiveness and serum IgE level in asthma. IgE may play an important role in facilitating the development of bronchial responsiveness and eosinophilic inflammation.
Objective To investigate the value of central venous-to-arterial carbon dioxide difference/arterial-to-venous oxygen difference ratio [P(cv-a)CO2/C(a-cv)O2] in predicting oxygen metabolism after fluid resuscitation in patients with septic shock. Methods A prospective observational study was carried out on septic shock patients admitted in the intensive care unit of Nanjng Drum Tower Hospital from November 2013 to April 2014. All patients underwent fluid challenge (300 ml saline for 20 min, rapid intravenous infusion). The patients were divided into a fluid responded group (ΔCI≥10%) and a fluid unresponded group (ΔCI＜10%), according to the change of cardiac output index (ΔCI) after fluid challenge. Then the patients were divided into two subgroups in the fluid responded group, namely a ΔVO2≥10% group and a ΔVO2＜10% group, according to the change of VO2 (ΔVO2). Cardiac output index (CI) were determined by pulse indicator continuous cardiac output (PICCO). Hemoglobin, arterial carbon dioxide (PaCO2), arterial oxygen (PaO2), arterial oxygen saturation (SaO2), arterial blood lactate, central venous carbon dioxide (PcvCO2), central venous oxygen (PcvO2) and central venous oxygen saturation (ScvO2) were measured by blood gas analysis. P(cv-a)CO2/C(a-cv)O2 and oxygen consumption (VO2) were calculated. P(cv-a)CO2/C(a-cv)O2 before and after fluid challenge was compared between two subgroups. Results Fluid challenges were performed in 23 instances in 18 patients, among which 17 instances were defined as the fluid responded group. Compared with the fluid unresponded group, P(cv-a)CO2/C(a-cv)O2, arterial lactate and ScvO2 had no significant difference [P(cv-a)CO2/C(a-cv)O2](mm Hg/ml): 2.05±0.75vs. 1.58±0.67; arterial lactate (mmol/l): 3.78±2.50vs. 3.26±2.42; ScvO2(%): 73.71±9.64vs. 70.30±12.01,P＞0.05] in the fluid responded group before resuscitation. In the fluid responded group, there were 10 instances in the ΔVO2≥10% group and 7 instances in the ΔVO2＜10% group. P(cv-a)CO2/C(a-cv)O2 (mm Hg/ml) was significantly higher in the ΔVO2≥10% group before resuscitation compared with the ΔVO2＜10% group (2.43±0.73vs. 1.51±0.37,P＜0.01). Lactate (mmol/l) was also higher in the ΔVO2≥10% group before resuscitation (4.53±2.52vs. 1.46±0.82,P＜0.01). ScvO2 (%) had no significant difference between two groups (70.79±9.15vs. 72.13±13.42,P＞0.05). The areas under ROC curve (AUCs) of P(cv-a)CO2/C(a-cv)O2, lactate and ScvO2 for predicting ΔVO2≥10% were 0.843, 0.921, and 0.529, respectively. The sensitivity and specificity of P(cv-a)CO2/C(a-cv)O2≥1.885 mm Hg/ml for predicting ΔVO2≥10% after fluid resuscitation were 70% and 86%, respectively. Conclusion For septic shock patients with fluid responsiveness, P(cv-a)CO2/C(a-cv)O2 can predict oxygen metabolism after fluid resuscitation and can be used as a reliable parameter to guide fluid resuscitation.