41 cases of chronic obstructive pulmonary disease caused by occupational irritating chemicals / 中华劳动卫生职业病杂志

Objective: To analyze the case characteristics of Chronic obstructive pulmonary disease caused by occupational irritant chemicals (OI-COPD). To provide basis for revising its diagnostic criteria. Methods: From June to December 2021, we investigated the information of OI-COPD patients confirmed by Shandong Institute of Occupational Health and Prevention of Occupational Diseases, Guangxi Zhuang Autonomous Region Institute of Occupational Disease Prevention and Control, Qingdao Central Hospital affiliated to Qingdao University and other diagnostic institutions in the past five years, a total of 41 cases. The basic information of OI-COPD cases, occupational risk factors exposure information, medical history, smoking history and clinical symptoms were analyzed retrospectively. The measurement data were tested for normal distribution, which was described by x±s, and compared between groups by t test; Those who do not conform to the normal distribution are described by the median [M (Q(1), Q(3)) ] and analyzed by nonparametric test; The counting data were expressed in frequency and rate (% ), and the comparison between groups was tested. Results: Of the 41 cases, 33 were male and 8 were female. The age of the patient diagnosed with OI-COPD was (49.5±10.3) years old, and the minimum age was 30 years old; Among them, 8 patients had a definite long-term smoking history (more than 5 years) ; The exposure duration of occupational risk factors was (18.6±10.3) years, of which 3 patients had exposure duration of less than 5 years; The occupational risk factors leading to OI-COPD include acids and acid-forming compounds, bases, aldehydes, nitrogen oxides, chlorine and its compounds, etc. The exposure level of occupational risk factors is related to the degree of COPD airflow restriction (χ(2)=6.17, P <0.05). 18 patients with diagnosis age <50 years old were diagnosed as early-onset COPD. The incidence of respiratory symptoms in the early diagnosis COPD group was lower than that in the non-early diagnosis COPD group, and the FEV1% pred was significantly higher than that in the non-early diagnosis COPD group. The difference was statistically significant (P<0.01 ) . Conclusion: The exposure level of occupational risk factors may be the risk factor affecting the degree of COPD airflow restriction. With the increase of the exposure level of COPD patients, the proportion of respiratory symptoms will also increase accordingly.

Comparative study on quantitative evaluation of normal salivary glands function by diffusion-weighted MR imaging after gustatory stimulation using two different stimuli / 中华放射学杂志

Objective To investigate the difference of apparent diffusion coefficients (ADCs) changes in three major salivary glands after gustatory stimulation using two different stimuli. Methods Thirty healthy volunteers were examined with a 1.5 T MR unit. A diffusion-weighted MR imaging (MR DWI) sequence was performed once at rest and continuously repeated 13 times after gustatory stimulation using a commercially available lemon juice and vitamin C tablets in the same volunteer by using self-controlled method. The subsequence of two stimuli was random. In addition, the salivary flow rates at rest and after stimulation were measured. Characteristics and differences in ADCs curves of three salivary glands before and after stimulation between two stimuli were analyzed. Comparison of maximum ADCs, maximum ADCs increase rates (IRs) and times to maximum ADCs(Tmax) between two stimuli was performed by using independent-samples t test. Correlation analysis between rest salivary flow rates and rest ADCs, the maximum salivary flow rates and ADCs after stimulation, the maximum salivary flow IRs and ADC IRs after stimulation were performed by using Pearson correlation test. Results In lemon juice stimulation group, the mean ADCs mostly showed a steady increase to peak values during the first DW MRI scan after stimulation in all glands, followed by a gradually decrease fluctuating slightly around the baseline values. In vitamin C stimulation group, the mean ADCs were significantly increased in all glands during the first DW MRI scan after stimulation, followed by a gradual upward trend till peak values. In lemon juice stimulation group, the mean Tmax of submandibular and sublingual glands[(184±122)s, (345±232)s, respectively] were significantly earlier than those[(454 ± 301)s, (528 ± 297)s, respectively] in vitamin C stimulation group (t=-3.517 and-2.548 respectively, P0.05). Conclusion MR DWI with transient stimulation using lemon juice is more stable for evaluating the physiologic changes of salivary glands in vivo.

Effect of noxious stimulation factor on γ-aminobutyric acid distribution in dog spinal cord during propofol anesthesia / 中华麻醉学杂志

Objective To evaluate the effect of the noxious stimulation factor on γ-aminobutyric acid (GABA) distribution in dog spinal cord during propofol anesthesia.Methods Sixteen healthy mongrel dogs of both sexes,aged 12-18 months,weighing 10-12 kg,were randomly divided into 2 groups (n =8 each):noxious stimulation group (S group) and control group (C group).Anesthesia was induced with propofol 7 mg/kg.The animals were mechanically ventilated after tracheal intubation.Right femoral artery was cannulated for mean arterial pressure (MAP) and pulse rate monitoring.Anesthesia was maintained with propofol infusion at a constant rate of 70 mg· kg-1 · h-1.5 ％ formalin 300 μl was subcutaneously injected into the central region of tails in group S,while the equal volume of normal saline was injected instead of formalin in group C.MAP and pulse rate were recorded before injection of formalin or normal saline (T1) and after injection of formalin or normal saline (T2).The dogs were scarified by decapitation at 50 min of continuous propofol infusion and cervical 2-3 segments of the spinal cord were removed for determination of GABA level in different regions of the spinal cord (frontal horn,posterior horn,intermediate zone,frontal funiculus,posterior funiculus and lateral funiculus) by HPLC.Results MAP and pulse rate were significantly higher at T2 than at T1 in S group (P ＜ 0.05).There were no significant differences in GABA level among the different regions of the spinal cord in C group (P ＞ 0.05).Compared with C group,GABA level in the frontal horn and posterior horn was significantly increased (P ＜ 0.05),and no significant change was found in the other regions of the spinal cord in S group (P ＞ 0.05).Conclusion The noxious stimulation factor can induce an increase in GABA level in the frontal horn and posterior horn of dog spinal cord during propofol anesthesia.