Diabetic visceral neuropathy of gastroparesis: Gastric mucosal innervation and clinical significance.

BACKGROUND AND PURPOSE: The pathogenesis of diabetic gastroparesis due to visceral neuropathy involves multidimensional mechanisms with limited exploration of gastric mucosal innervation. This study aimed to examine quantitatively this topic and its relationship with gastroparesis symptoms and gastric emptying in diabetes. METHODS: We prospectively enrolled 22 patients with type 2 diabetes and gastroparesis symptoms and 25 age- and gender-matched healthy controls for comparison. The assessments included: (i) neuropathology with quantification of gastric mucosal innervation density (MID) on endoscopic biopsy; (ii) clinical manifestations based on the Gastroparesis Cardinal Symptom Index (GCSI) questionnaire; and (iii) functional tests of gastric emptying scintigraphy (GES). RESULTS: In patients with diabetes, stomach fullness, bloating and feeling excessively full after meals constituted the most common GCSI symptoms. Seven patients with diabetes (32%) had prolonged gastric emptying patterns. In diabetes, gastric MID was significantly lower in all the regions examined compared with the controls: antrum (294.8 ± 237.0 vs. 644.0 ± 222.0 mm/mm3 ; p < 0.001), body (292.2 ± 239.0 vs. 652.6 ± 260.9 mm/mm3 ; p < 0.001), and fundus (238.0 ± 109.1 vs. 657.2 ± 332.8 mm/mm3 ; p < 0.001). Gastric MID was negatively correlated with gastroparesis symptoms and total scores on the GCSI (p < 0.001). Furthermore, gastric MID in the fundus was negatively correlated with fasting glucose and glycated hemoglobin levels. Gastric emptying variables, including half emptying time and gastric retention, were prolonged in patients with diabetes, and gastric retention at 3 h was correlated with fasting glucose level. CONCLUSION: In diabetes, gastric MID was reduced and GES parameters were prolonged. Both were correlated with gastroparesis symptoms and glycemic control. These findings provide pathology and functional biomarkers for diabetic visceral neuropathy of gastroparesis and underlying pathophysiology.

Preliminary Study on Changes of Sleep EEG Power and Plasma Melatonin in Male Patients With Major Depressive Disorder After 8 Weeks Treatment.

Objective: To clarify the effects of escitalopram on sleep EEG power in patients with Major depressive disorder (MDD). Method: Polysomnography (PSG) was detected overnight, and blood samples were collected at 4 h intervals over 24 h from 13 male healthy controls and 13 male MDD patients before and after treatment with escitalopram for 8 weeks. The outcome measures included plasma melatonin levels, sleep architecture, and the sleep EEG power ratio. Results: Compared with healthy controls, MDD patients presented abnormalities in the diurnal rhythm of melatonin secretion, including peak phase delayed 3 h and a decrease in plasma melatonin levels at night and an increase at daytime, accompanied by sleep disturbances, a decrease in low-frequency bands and an increase in high-frequency bands, and the dominant right-side brain activity. Several of these abnormalities (abnormalities in the diurnal rhythm of melatonin secretion, partial sleep architecture parameters) persisted for at least the 8-week testing period. Conclusions: Eight weeks of treatment with escitalopram significantly improved subjective sleep perception and depressive symptoms of patients with MDD, and partially improved objective sleep parameters, while the improvement of circadian rhythm of melatonin was limited.

Small fiber pathology in autism and clinical implications.

OBJECTIVE: To investigate small fiber innervation of the skin and its relationships with clinicometry of autism and peripheral afferents for contact heat-evoked potential (CHEP) and psychophysical measures of thermal thresholds. METHODS: We recruited 32 men with autism (26.5 ± 5.9 years) and conducted small fiber assessments of skin biopsy with quantifying intraepidermal nerve fiber (IENF) density, CHEP, quantitative sensory testing, and large fiber physiology of nerve conduction studies. Results were compared with age-matched controls and analyzed with clinical measures of autism. RESULTS: Patients with autism showed a lower IENF density than controls (5.53 ± 2.09 vs 11.13 ± 3.49 fibers/mm, p < 0.0001). The IENF density was reduced in 17 (53.1%) men with autism classified as skin denervation group. On psychophysics, 9 (28%) men with autism had elevated thermal thresholds, and the warm threshold of the big toe was negatively correlated with IENF density (p = 0.0073), indicating functional impairments of small fiber sensory nerves. IENF density was negatively correlated with CHEP amplitude in autism (p = 0.003), in contrast to the pattern of positive correlation in controls, indicating different processing of nociceptive afferent in autism. Clinically, IENF density was related to distinct tactile symptom patterns in the skin denervation vs normal innervation group, respectively. Furthermore, IENF density was associated with autistic symptoms measured by the Autism Spectrum Quotient in a U-shaped model (p = 0.014). CONCLUSIONS: These observations indicated that a substantial portion of individuals with autism had small fiber pathology, which was associated with tactile and autistic symptoms, providing structural and physiologic evidence for the involvement of peripheral sensory nerves in autism.

Relationship Between Particulate Matter (PM2.5) and Hospitalizations and Mortality of Chronic Obstructive Pulmonary Disease Patients: A Meta-Analysis.

BACKGROUND: Numerous studies have reported associations between particulate matter with aerodynamic diameters of ≤2.5 µm (PM2.5) and chronic obstructive pulmonary disease (COPD) hospitalizations and mortality in cities worldwide. Nonetheless, the evidence of an association remains varied and limited. METHODS: Systematic searches were conducted in 6 common English and Chinese electronic databases (i.e., PubMed, Web of Science, EMBASE, Ovid, Google Scholar, and China National Knowledge Infrastructure [CNKI]). A meta-analysis was performed to estimate the odds ratio (OR) to evaluate the relationship between PM2.5 and COPD hospitalizations and mortality. Publication bias and heterogeneity of samples were tested using a funnel plot and the Egger's test. Studies were analyzed using either a random-effect model or a fixed-effect model. RESULTS: The search yielded 18 studies suitable for meta-analysis during the period from Jan 1, 2010 to Dec 31, 2018. A 10-µg/m³ increase in PM2.5 was associated with a 2.5% (95% confidence interval [CI]: 1.8-3.2%) increase in COPD hospitalizations, with an OR of 1.025 (95% CI: 1.018-1.032), and a 1.5% (95% CI: 0.9-2.2%) increase in COPD mortality, with an OR of 1.015 (95% CI: 1.009-1.022). Comparing different age groups, elderly people were more sensitive to the adverse effects. The estimated risk was higher in European countries than Asian countries, and in warm compared cold seasons. Various additional confounding factors also led to different results. CONCLUSIONS: PM2.5 is associated with COPD hospitalizations and mortality. Controlling ambient air pollution would provide benefits to COPD patients.

Hybrid nano-textured nanogenerator and self-powered sensor for on-skin triggered biomechanical motions.

Researchers have made a lot of effort for the lightweight and high flexibility of wearable electronic devices, which also requires the associated energy harvesting equipment to have ultra-thin thickness and high stretchability. Therefore, a piezoelectric-triboelectric hybrid self-powered sensor (PTHS) has been proposed which can be used as the second layer of the human body. This elastic PTHS can even work on a person's fingers without disturbing the body's movements. The open circuit voltage and short circuit current of devices with a projected area of 30 mm × 25 mm can reach 1.2 V and 30 nA, respectively. Two piezoelectrically-triboelectrically sensors with machine learning optimized identification strategies were experimentally proven as the potential applications of the PTHS. The PTHS's ultra-thin thickness, high stretchability and superior geometry control features are promising in electronic skin, artificial muscle and soft robotics. The novelty of this work is that a smart mask integrated with PTHS can generate a signal of the hybrid sensor for the biomechanical motion classifier. After suitable training, an overall accuracy of 87.9% using long short-term memory can be achieved.

[Effects of Ringer's solution with different concentrations of alcohol on biphasic compound action potentials of frog sciatic nerve trunk].

OBJECTIVE: To quantitatively investigate the effects of Ringer's solution with different concentrations of alcohol (1%～80%) on biphasic compound action potentials (AP) from frog sciatic nerve trunk, and their recoveries from alcohol effects. METHODS: Individual segments of frog sciatic nerve trunk with a length of 6 to 8 cm were prepared. Ringer's solution with different concentrations of alcohol (0%, 1%, 2%, 4%, 8%, 16%, 32%, 48%, 64% and 80%) was applied onto the segment of the trunk between the stimulus and ground electrodes via an agent reservoir which was newly armed in a nerve trunk shielded chamber for 5 minutes. The nerve trunk was respectively electro-stimulated to generate the biphasic compound AP which was recorded using the experimental system of BL-420F. This was followed by 5 times washout plus 5 min administration with Ringer's solution before recovery recording of AP. RESULTS: Compared to normal Ringer's solution, Ringer's solution with alcohol at ≤4% did not have dramatic impacts on the AP amplitude and conduction velocity, while Ringer's solution with alcohol at ≥8% there was significant decrease in these two parameters. Ringer's solution with alcohol at the conentrations of 16%, 32% and ≥48% could prevent a small proportion (30%), a large proportion (90%) and all (100%) of sciatic nerve trunks, respectively, from generating AP. Washout with normal Ringer's solution after alcohol application at the concentration of ≤32%, AP could totally recover to normal status. While alcohol at the concentration of 48%, 64% and 80%, the probabilities to regenerate APs were 90%, 40% and 0%, and the AP amplitudes were decreased to 60%, 36% and 0%, respectively. After washout, AP conduction velocity showed no difference with alcohol at the concentration of ≤8% when compared with that before washout, while it could not be recovered to normal under alcohol at ≥16%. CONCLUSION: Ringer's solution with different concentrations of alcohol exerts different effects on biphasic compound AP amplitude and conduction velocity. Hopefully, our findings could be helpful for the alcoholic usage and its recovery from alcoholic damage.

Neuroimaging signatures of brain plasticity in adults with prenatal exposure to polychlorinated biphenyls: Altered functional connectivity on functional MRI.

Prenatal exposure to polychlorinated biphenyls (PCBs), persistent organic pollutants in food chains and environment, exerts negative effects on children's cognitive function. To study the long-term effects, we examined cognitive functions in the male children of women with substantial PCB exposure in Taiwan during 1978-1979 and investigated neural basis of cognitive function changes through structural magnetic resonance imaging (MRI) and functional MRI (fMRI), which included resting-state and task-activated fMRI with two paradigms: a 2-back task and a picture rotation task. Ten men aged 30.0 ±â€¯3.7 years with prenatal exposure to PCBs and 11 unexposed controls aged 28.1 ±â€¯3.1 years participated. Both groups had similar cognitive phenotypes and behavioral results. Structural MRI analysis results showed that the PCB group had increased cortical thickness over the right inferior parietal lobule. In the resting-state study, the PCB group showed alterations in the default mode network. During the tasks, the PCB group showed decreased task-induced deactivation signals in cognition-associated brain areas during the 2-back task but enhanced deactivations during the picture rotation task. This study demonstrated altered structural MRI as well as resting and task-related fMRI in men with prenatal PCB exposure, suggesting altered brain plasticity and compensatory neuropsychological performance.

Attenuated contact heat-evoked potentials associated with sensory and social-emotional symptoms in individuals with autism spectrum disorder.

Sensory disturbance is associated with socio-emotional problems in individuals with autism spectrum disorder (ASD). Most studies assess sensory symptoms by self-reports, which are largely limited by the language ability and self-awareness of the individuals. This study aims to investigate sensory disturbance by contact heat-evoked potentials (CHEP) in ASD individuals, and to examine the clinical correlates of CHEP parameters. We compared the CHEP parameters and reported pain between 31 ASD individuals (aged 20.5 ± 5.2 years) and and 22 typically-developing controls (TD, aged 21.4 ± 2.6), and correlated the CHEP parameters with self-reported sensory symptoms and attention/socio-emotional symptoms. We found that ASD individuals showed smaller P2-wave amplitudes than TD, even though they reported a similar level of pain. In TD individuals, a smaller P2-wave amplitude was related to higher scores on 'low registration,' 'attention to detail,' and 'attention switching difficulties.' In ASD individuals, longer N2-wave latency was related to higher scores on 'sensory sensitivity' and socio-emotional problems; while higher reported pain was associated with higher scores on 'low registration,' overall autistic severity, and longer N2-wave latency. Our findings of attenuated CHEP response in ASD, which was associated with sensory symptoms and socio-emotional problems, suggest a potential role for CHEP in studying sensory disturbances in ASD.

Biomarkers of neuropathic pain in skin nerve degeneration neuropathy: contact heat-evoked potentials as a physiological signature.

Contact heat-evoked potentials (CHEPs) have become an established method of assessing small-fiber sensory nerves; however, their potential as a physiological signature of neuropathic pain symptoms has not been fully explored. To investigate the diagnostic efficacy in examining small-fiber sensory nerve degeneration, the relationship with skin innervations, and clinical correlates with sensory symptoms, we recruited 188 patients (115 men) with length-dependent sensory symptoms and reduced intraepidermal nerve fiber (IENF) density at the distal leg to perform CHEP, quantitative sensory testing, and nerve conduction study. Fifty-seven age- and sex-matched controls were enrolled for comparison of CHEP and skin innervation. Among patients with neuropathy, 144 patients had neuropathic pain and 64 cases had evoked pain. Compared with quantitative sensory testing and nerve conduction study parameters, CHEP amplitudes showed the highest sensitivity for diagnosing small-fiber sensory nerve degeneration and exhibited the strongest correlation with IENF density in multiple linear regression. Contact heat-evoked potential amplitudes were strongly correlated with the degree of skin innervation in both patients with neuropathy and controls, and the slope of the regression line between CHEP amplitude and IENF density was higher in patients with neuropathy than in controls. Patients with evoked pain had higher CHEP amplitude than those without evoked pain, independent of IENF density. Receiver operating characteristic analysis showed that CHEP had better performance in diagnosing small-fiber sensory nerve degeneration than thermal thresholds. Furthermore, CHEPs showed superior classification accuracy with respect to evoked pain. In conclusion, CHEP is a sensitive tool to evaluate pathophysiology of small-fiber sensory nerve and serves as a physiological signature of neuropathic pain symptoms.

[Interactions between Goethite and Humic Acid and the Stability of Goethite-Humic Acid Complex].

Goethite-humic acid complex was prepared in a suspension containing goethite and humic acid. X-ray diffraction (XRD) results showed that the crystal structure of this complex had no obvious changes compared to pure goethite, but the peak intensity of the complex was slightly reduced. Transmission electron microscopy (TEM) images indicated that the surface of the goethite was coated by particles of humic acid. Compared to the infra-red (IR) spectra of goethite and humic acid, the anti-vibrational frequencies of COO- and the vibrational frequencies of ≡Fe-OH decreased by 20 cm-1 and 9 cm-1, respectively, while the vibrational frequencies of the associated hydroxyls increased by 10 cm-1 and the absorption band of carboxylic C-O and free hydroxyls almost disappeared. This indicates that the interactional mechanisms between goethite and humic acid include the monodentate coordination of Fe(Ⅲ) -carboxylate and hydrogen-bonds. Thermogravimetry/differential thermogravimetry (TG/DTG) analysis showed that the temperature of the weight loss peak for ≡Fe-OH in goethite and the complex were 258℃ and 276℃, respectively. This indicates that the coating of humic acid enhances the heat stability of ≡Fe-OH in goethite. Compared with humic acid, the temperature of the weight loss peak for aliphatic organics and aromatic organics in complex decreased by 60℃ and 26℃, respectively and the ratio of weight loss from aliphatic organics to aromatic organics in complex increased. This indicates that organics with a lower heat stability may be more easily adsorbed onto goethite and the affinity to goethite was higher for the aliphatic organics than for aromatic organics. After ultrasonic dispersion, the content of large particles (≥ 2 µm) decreased significantly for both goethite and humic acid, but the content and the size of large particles in the complex changed only slightly.

Pathophysiology of Small-Fiber Sensory System in Parkinson's Disease: Skin Innervation and Contact Heat Evoked Potential.

Sensory symptoms are frequent nonmotor complaints in patients with Parkinson's disease (PD). However, few investigations integrally explored the physiology and pathology of the thermonociceptive pathway in PD. We aim to investigate the involvement of the thermonociceptive pathway in PD.Twenty-eight PD patients (16 men, with a mean age and standard deviation of 65.6 ±â€Š10.7 years) free of neuropathic symptoms and systemic disorders were recruited for the study and compared to 23 age- and gender-matched control subjects (12 men, with a mean age and standard deviation of 65.1 ±â€Š9.9 years). We performed skin biopsy, contact heat-evoked potential (CHEP), and quantitative sensory tests (QST) to study the involvement of the thermonociceptive pathway in PD.The duration of PD was 7.1 ±â€Š3.2 (range 2-17 years) years and the UPDRS part III score was 25.6 ±â€Š9.7 (range 10-48) during the off period. Compared to control subjects, PD patients had reduced intra-epidermal nerve fiber (IENF) density (2.48 ±â€Š1.65 vs 6.36 ±â€Š3.19 fibers/mm, P < 0.001) and CHEP amplitude (18.02 ±â€Š10.23 vs 33.28 ±â€Š10.48 µV, P < 0.001). Twenty-three patients (82.1%) had abnormal IENF densities and 18 (64.3%) had abnormal CHEP. Nine patients (32.1%) had abnormal thermal thresholds in the feet. In total 27 patients (96.4%) had at least 1 abnormality in IENF, CHEP, or thermal thresholds of the foot, indicating dysfunctions in the small-fiber nerve system. In control subjects, CHEP amplitude linearly correlated with IENF density (P < 0.001). In contrast, this relationship disappeared in PD (P = 0.312) and CHEP amplitude was negatively correlated with motor severity of PD independent of age, gender, and anti-PD medication dose (P = 0.036), suggesting the influences of central components on thermonociceptive systems in addition to peripheral small-fiber nerves in PD.The present study suggested impairment of small-fiber sensory system at both peripheral and central levels is an intrinsic feature of PD, and skin biopsy, CHEP, and QST provided an integral approach for assessing such dysfunctions.

The Influence of Secular Trends in Body Height and Weight on the Prevalence of Overweight and Obesity among Chinese Children and Adolescents.

OBJECTIVE: To explore the influence of secular trends in body height and weight on the prevalence of overweight and obesity among Chinese children and adolescents. METHODS: The data were obtained from five cross-sectional Chinese National Surveys on Students' Constitution and Health. Overweight/obesity was defined as BMI-for-age Z-score of per the Wold Health Organization (WHO) reference values. Body height and weight for each sex and age were standardized to those reported in 1985 (standardized height: SHY; standardized weight: SWY) and for each sex and year at age 7 (standardized height: SHA; standardized weight: SWA) using the Z-score method. RESULTS: The prevalence of overweight/obesity in Chinese children was 20.2% among boys and 10.7% among girls in 2010 and increased continuously from 1985 to 2010. Among boys and girls of normal weight, SHY and SHA were significantly greater than SWY and SWA, respectively (P < 0.001). Among boys and girls with overweight/obesity, SHY was significantly lower than SWY (P < 0.001), and showed an obvious decreasing trend after age 12. SHA was lower than SWA among overweight boys aged 7-8 years and girls aged 7-9 years. SHY/SHW and SHA/SWA among normal-weight groups were greater than among overweight and obese groups (P < 0.001). CONCLUSION: The continuous increase in the prevalence of overweight/obesity among Chinese children may be related to a rapid increase in body weight before age 9 and lack of secular increase in body height after age 12.

[Effect of Fe-Mn-Si on the biomass structure of Eichhornia crassipes].

Eichhornia crassipes (water hyacinth) was cultivated under different iron (Fe), manganese (Mn) and silicon (Si) nutrient treatments for its biomass characteristics research which was determined by various items including nutrient element content (Fe, Mn and Si), adsorption sites and active function groups. The results show that Mn and Si can enhance acidic sites of the plant, in which Mn plays a great role, but Fe reduces the acidic sites. The sequence of acidic sites' amount among three parts of the plant is root > stem > leaf, in the treatment of Fe, Mn and their combination, and leaf > stem > root in Si treatment. The amount of alkaline sites is less than that of acidic sites, and the difference in their distributions among three parts of the plant is not great. Mn and Si treated Eichhornia crassipes stalks have more amorphous material, such as lignin, pectin and xylan (hemicellulose), which have more functional groups of -OH, -COOH and acidic sites.

[Long-term effects of air pollution on the occurrence of respiratory symptoms in adults of Beijing].

OBJECTIVE: To investigate the long-term effects of air pollution on prevalence of respiratory symptoms in adults, in Beijing. METHODS: A cross-sectional study was conducted in an urban area and a suburban area with different levels of air pollution in October 2008, in Beijing. Respiratory symptoms were investigated by a standard questionnaire from the American Thoracic Society (ATS-DLD-78-A) in 9 052 adults who had lived there for at least two years. The concentrations of air pollutants for recent five years were obtained from Reports on the Quality of the Beijing Environment, Environmental Protection Bureau and Statistics Yearbook. The differences of the prevalence and standardized prevalence of respiratory symptoms in adults between the urban and suburban areas were analyzed by χ(2) test. RESULTS: The standardized prevalences of persistent phlegm and asthma in urban adults were significantly higher than those in suburban adults [(3.06% vs. 2.43%, P<0.05) and (0.65% vs. 0.31%, P<0.01), respectively], but lower than that of the breathless (0.75% vs. 1.12%, P<0.05). CONCLUSION: The study suggested that ambient air pollution had long-term effects on the prevalence of some respiratory symptoms in adults.

[The comparison of the indoor environmental factors associated with asthma and related allergies among school-child between urban and suburban areas in Beijing].

OBJECTIVE: To study the indoor environmental factors associated with the prevalence of asthma and related allergies among school children. METHODS: A cluster sampling method was used and the ISAAC questionnaire was conducted. A total of 4612 elementary students under Grade Five of 7 schools were enrolled in the survey for the impact of indoor environmental factors on the prevalence of asthma and related allergies in several urban and suburban schools of Beijing. RESULTS: A total of 4060 sample were finally analyzed including 1992 urban and 2068 suburban. The prevalence of wheeze, allergic rhinoconjunctivitis and atopic eczema in the past 12 months was 3.1% (61/1992), 5.3% (106/1992), 1.1% (22/1992) among urban children while 1.3% (27/2068), 3.1% (65/2068), 1.0% (22/2068) among suburban children respectively. The prevalence of wheeze and allergic rhinoconjunctivitis of the past 12 months in urban were both significantly higher than that in suburban (χ(2) = 14.77, 11.93, P < 0.01). The incidences of having asthma and eczema ever among urban children (5.3% (105/1992), 29.4% (586/1992)) were significantly (χ(2) = 39.03, 147.22, P < 0.01) higher than that among suburban (1.7% (35/2068), 13.8% (285/2068)). Although the distributions of indoor environmental factors were similar in both areas, passive smoking and interior decoration had different influence on the prevalence of asthma and related allergies among school children in the two areas. The significant impact of passive smoking on having asthma ever among suburban children was observed (OR = 2.70, 95%CI = 1.17 - 6.23) while no significant result in urban (OR = 1.06, 95%CI = 0.71 - 1.58); the percentage of interior decoration was 84.0% (1673/1992) among urban children and 80.0% (1655/2068) among suburban children, there was significant impact of interior decoration on the prevalence of having eczema ever among urban children (OR = 1.57, 95%CI = 1.17 - 2.10) but no significant results were found in suburban sample (OR = 1.06, 95%CI = 0.76 - 1.48). CONCLUSION: The prevalence of asthma and related allergies among school children is much higher in urban areas than that in suburban areas and the indoor environmental factors such as passive smoking and interior decoration may differently explain the prevalence of asthma and related allergies in the two areas.

[Short-time effects of inhalable particles and fine particles on children's lung function in a district in Beijing].

OBJECTIVE: To study short-term effects of PM10 (particulate matter of aerodynamic diameter <10 microm) and PM2.5 (particulate matter of aerodynamic diameter <2.5 microm) on children's lung function in one district in Beijing. METHODS: Two hundred and sixteen healthy students aged between 7 and 11 year-old were selected from two primary schools in Beijing in October 2008, and every subject was tested with eight lung function parameters. Levels of PM2.5 in the schoolyards were monitored. Temperature and relative humidity were also recorded. PM10 data was collected from the nearby monitoring sites. The association between children's lung function and PM10 and PM2.5 were analyzed by using ridge regression model. RESULTS: The decrements found in indicators reflecting large airway characteristics including slow vital capacity (SVC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1.0), and in indicators reflecting small airway characteristics including forced expiratory flow between 25% and 75% of vital capacity (FEF25-75), forced expiratory flow after 25% of vital capacity has been expelled (FEF25), forced expiratory flow after 50% of vital capacity has been expelled (FEF50), were associated with accumulated 1-day lagged and 2-day lagged PM2.5 and PM10, while FVC and FEV1.0 decreased more significantly, and the declines of SVC, FVC and FEV1.0 in girls were slightly greater than that in boys. CONCLUSION: PM2.5 and PM10 had short-term adverse health effects on children's lung function. The effects on parameters reflecting large airway characteristics such as FVC and FEV1.0 were even more obvious. The large airways of girls might be more susceptible to ambient particulate matter.

[Pollutions of indoor fine particles in four types of public places and the influencing factors].

OBJECTIVE: To study the levels of pollutions caused by fine particulate matter (PM(2.5)) in the public places and investigate the possible influencing factors. METHODS: A total of 20 public places in four types such as rest room in bath center, restaurant, karaoke bars and cyber cafe in Tongzhou district in Beijing were chosen in this study; indoor and outdoor PM(2.5) was monitored by TSI sidepak AM510. Data under varying conditions were collected and analyzed, such as doors or windows or mechanical ventilation devices being opened, rooms cramped with people and smoking. RESULTS: The average concentration of indoor PM(2.5) in 20 public places was (334.6 +/- 386.3) microg/m(3), ranging from 6 microg/m(3) to 1956 microg/m(3); while in bath center, restaurant, karaoke bars and cyber cafe were (116.9 +/- 100.1)microg/m(3), (317.9 +/- 235.3) microg/m(3), (750.6 +/- 521.6)microg/m(3) and (157.5 +/- 98.5) microg/m(3) respectively. The concentrations of PM(2.5) in restaurant (compared with bath center: Z = -10.785, P < 0.01; compared with karaoke bars: Z = -10.488, P < 0.01; compared with cyber cafe: Z = -7.547, P < 0.01) and karaoke bars (compared with bath center: Z = -16.670, P < 0.01; compared with cyber cafe: Z = -15.682, P < 0.01) were much higher than those in other two places. Single-factor analysis revealed that the average concentration of indoor PM(2.5) in 20 public places was associated with the number of smokers per cube meters(9.13 x 10(-3); r = 0.772, F = 26.579, P < 0.01) and ventilation score [(2.5 +/- 1.5) points; r = 0.667, F = 14.442, P < 0.01], and there were significant correlation between the average indoor and outdoor levels in restaurant [(317.9 +/- 235.3) microg/m(3), (67.8 +/- 78.9) microg/m(3); r = 0.918, F = 16.013, P = 0.028] and cyber cafe [(157.5 +/- 98.5) microg/m(3), (67.7 +/- 43.7) microg/m(3); r = 0.955, F = 30.785, P = 0.012]. Furthermore, significant correlation was observed between the average concentration of indoor PM(2.5) [(157.5 +/- 98.5) microg/m(3)]and the number of people per cube meters (288.7 x 10(-3)) in cyber cafe (r = 0.891, F = 11.615, P = 0.042). Multiple regression analysis showed that smoking (b' = 0.581, t = 3.542, P = 0.003) and ventilation (b' = -0.348, t = -2.122, P = 0.049) were the major factors that may influence the concentration of indoor PM(2.5) in four public places. With cluster analysis, the results showed that the major factors that influence the concentration of indoor PM(2.5) was the outdoor PM(2.5) levels [(49.6 +/- 39.5) microg/m(3); b = 1.556, t = 3.760, P = 0.007] when ventilation (score > 2) was relatively good. The number of smokers per cube meters (14.7 x 10(-3)) became the major influence factor when the ventilation score

[Determination of trace beryllium in geological samples by oxygen doped air-acetylene flame atomic absorption spectrometry].

A new method for the determination of trace beryllium in geological samples by oxygen-air-acetylene flame atomic absorption spectrometry is reported in the present paper. The optimum determination conditions were selected. When suitable amounts of 8-hydroxyquinoline are added, the interference effect from the coexisting elements can be minimized and the sensitivity for the determination of beryllium can be increased. The detection limit (k = 3) is 0.006 microg x mL(-1) for beryllium. The method has been applied to the determination of trace beryllium in geological standard samples, and the results are in good agreement with the certified values with a precision of 4.69% RSD( n = 8).