[Air Pollutant Spatiotemporal Evolution Characteristics and Effects on Human Health in Xi'an City].

Xi'an is the political, economic, and cultural center of northwest China with a developed industry. Air pollution incidents have brought great challenges to the high-quality development of the social economy. It is vital to study air pollution characteristics and clarify their impact on human health. In this study, we first analyzed the spatiotemporal variations in air pollutants in the study region from 2015 to 2021. Then, the air quality index (AQI), aggregate air quality index (AAQI), and health risk-based air quality index (HAQI) were used to assess health risks. Based on these, the AirQ2.2.3 model was used to quantify health effects. The results showed that the major pollutants were PM10, PM2.5, and O3. The main pollution characteristics of the study area were terrain characteristics and the mixed pollution of anthropogenic emissions. Compared to that of AQI, AAQI and HAQI showed better classification performance for pollution levels. HAQI revealed that approximately 80 % of the population was exposed to unhealthy air throughout the year in the study region. People were most exposed to unhealthy air in winter, followed by autumn and spring, and the least in summer. The AirQ2.2.3 model quantified the total mortality proportions attributable to PM2.5, PM10, SO2, CO, NO2, and O3, which were 0.99 %, 2.04 %, 0.41 %, 1.72 %, 8.76 %, and 3.67 %, respectively. The attributable proportion of mortality of the respiratory system and cardiovascular diseases was consistent with the change rule of total mortality.

[Acupoint sensitization enhances inhibitory effect of electroacupuncture on jejunum mobility in rats].

OBJECTIVE: To observe the effect difference of electroacupuncture (EA) at the sensitized and non-sensitized acupoint "Tianshu" (ST25) on the motility of jejunum in rats. METHODS: Male SD rats were randomly divided into blank control, sensitized ST25 (sensitization), and non-sensitized ST25 (non-sensitization) groups (n=16 in each group). The sensitization and non-sensitization were induced by injection of 15% mustard oil (20 µL) and Paraffin oil (20 µL) into the left ST25 area respectively. The rats' behavior reactions were assessed by recording the numbers and duration of licking the local sensitized skin region. At the end of experiments and after regular trans-cardiac perfusion and fixing with 10% neutral formaldehyde, the skin and muscular tissues of the ST25 region (1 cm×1 cm) were taken for H.E. staining to observe the local histopathologic changes. The intestinal motility was detected by recording the contraction pressure waves of jejunum through a small balloon-connected pressure transducer and an amplifier, followed by calculating the ratios of amplitude and frequency of contraction waves between pre- and post-EA stimulation. EA (2 Hz, 0.2-6.0 mA) was applied to the sensitized and non-sensitized ST25 regions for 20 s for comparing their effects on jejunum motility. RESULTS: Compared with the blank control group, mustard oil injection but not Paraffin oil injection resulted in histological edema and neutrophils infiltration in tissues of ST25 region, and also striking increase of the number and duration of licking (P<0.01), suggesting a sensitization of ST25 area after mustard oil injection. The ratios of spontaneous contraction amplitude and frequency of jejunum were remarkably decreased in mustard oil-treated rats compared to baseline and Paraffin oil group (P<0.001，P<0.01). The maximum inhibitory effect of EA on the intestinal movement amplitude was significantly higher in the sensitization group than in the blank control and non-sensitization groups (P<0.05，P<0.01), and there was a dose-effect relationship between the current intensity of EA (0.5-3.0 mA) and the inhibitory rate 50% of the contraction amplitude (not the frequency) in the sensitization group (P<0.001), but not in the blank control and non-sensitization groups (P>0.05). Additionally, 1.5 mA EA stimulation at the sensitized ST25 (not at the non-sensitized ST25) had an inhibitory effect on the contraction amplitude (P<0.05) rather than on the contraction frequency (P>0.05) in comparison with the blank control group. CONCLUSION: Sensitization of acupoint ST25 can modulate the motility of jejunum and enhances the inhibitory effect of EA on the contraction amplitude of jejunum in rats. The inhibitory effect of sensitized ST25 EA is evidently stronger than that of the non-sensitized ST25 EA.

[Manual acupuncture stimulation of acupoints at the same and adjacent spinal segments promotes uterine contractility].

OBJECTIVE: To investigate the effect of manual acupuncture stimulation of acupoints at different spinal nerve segments on uterine motility and the complicated adrenergic and cholinergic receptors. METHODS: Eighteen adult non-pregnant SD rats were used in the present study. The contractive activities of the uterus were measured by using a pressure transducer which was connected to an inserted water-filled balloon in the uterus via a PE tube at one end and an amplifier at the other end. Manual acupuncture needle was applied to "Zigong"(EX-CA1),"Huiyin" (CV1), "Xuehai "(SP10) and "Taichong "(LR3) acupoints located at the same or adjacent spinal nerve segments of the uterus, and to "Neiguan" (PC6) situated at the distant spinal nerve segment at about 2 Hz for 1 min, followed by observing changes of the uterine contractility. After acupuncture, α-adrenoceptor antagonist phentolamine (0.5 mg/kg, n=9) or cholinergic muscarinic (M) receptor antagonist atropine (0.5 mg/kg，n=9) was given to the rats of different acupoints respectively through tail vein, followed by observing changes of the uterine automatic systolic pressure difference (value of systolic pressure peak minuses the trough value) and frequency after manual acupuncture stimulation as well as after blocking the activities of α-adrenoceptors and M receptors, separately. RESULTS: After acupuncture stimulation of EX-CA1, CV1, SP10 and LR3, but not PC6, the systolic pressure difference and frequency of the uterus were signi-ficantly increased (P<0.05,P<0.001, P<0.01). Following intravenous injection of phentolamine, both the systolic pressure difference and frequency had no marked changes after acupuncture at the 5 acupoints (P>0.05). After intravenous injection of atropine, the uterine systolic pressure difference and frequency were markedly decreased compared with the basic values before acupuncture stimulation (P<0.001), but had no obvious changes after acupuncture at the 5 acupoints at both the same and distant spinal segments to the uterus (P>0.05). CONCLUSION: Manual acupuncture stimulation of acupoints at the same and adjacent spinal segments can promote the contractility of uterus in normal rats, which is realized by activating both α-adrenoceptor and cholinergic M receptors.