Water-soluble brown carbon in atmospheric aerosols from the resource-dependent cities: Optical properties, chemical compositions and sources

As a vital type of light-absorbing aerosol, brown carbon (BrC) presents inherent associations with atmospheric photochemistry and climate change. However, the understanding of the chemical and optical properties of BrC is limited, especially in some resource-dependent cities with long heating periods in northwest China. This study showed that the annual average abundances of Water-soluble BrC (WS-BrC) were 9.33±7.42 and 8.69±6.29 µg/m3 in Baotou and Wuhai and the concentrations, absorption coefficient (Abs365), and mass absorption efficiency (MAE365) of WS-BrC presented significant seasonal patterns, with high values in the heating season and low values in the non-heating season; while showing opposite seasonal trends for the Absorption Ångström exponent (AAE300-400). Comparatively, the levels of WS-BrC in developing regions (such as cities in Asia) were higher than those in developed regions (such as cities in Europe and Australia), indicating the significant differences in energy consumption in these regions. By combining fluorescence excitation-emission matrix (EEM) spectra with the parallel factor (PARAFAC) model, humic-like (C1 and C2) and protein-like (C3) substances were identified, and accounted for 61.40%±4.66% and 38.6%±3.78% at Baotou, and 60.33%±6.29% and 39.67%±4.17% at Wuhai, respectively. The results of source apportionment suggested that the potential source regions of WS-BrC varied in heating vs. non-heating seasons and that the properties of WS-BrC significantly depended on primary emissions (e.g., combustion emissions) and secondary formation.

The fate of Arsenic associated with the transformation of iron oxides in soils: The mineralogical evidence

The influence of iron (oxyhydr)oxides on the transformation and migration of arsenic(As) has garnered significant attention. Previous work has largely focused on the transformation of iron oxides related to As fate at molecular and mechanistic levels. However, studies examining the interplay between As concentration and iron oxides transformation within complex soil system are sparse. This study investigates the transformation of iron oxides in soils with varying As concentration during microbial dissimilatory iron reduction (DIR), employing humic acid (HA) as electron shuttle and assesses the impact on As speciation transformation. Comparative analyses indicate that in soils with high As concentration (>1000 mg/kg), the secondary transformation of iron (oxyhydr)oxides to other forms, such as the conversion of ferrihydrite to goethite and lepidocrocite, or schwertmannite to goethite, is impeded. Consequently, the formation of goethite and lepidocrocite, which would typically re-stabilize As, is inhibited, leading to elevated release of As(III). On the other hand, an increase in magnetite formation in soils with low As concentration (<100 mg/kg) appears to re-stabilize As effectively. Furthermore, the formation of new secondary iron (oxyhydr)oxides in soils with As concentration <200 mg/kg enhances fraction F5, which subsequently contributes to the re-immobilization of As, sequestering it within the soil matrix. This process results in a lower release of As(III) from soils with As concentration below 200 mg/kg. These findings enhance the understanding of the interdependent relationship between the transformation of iron oxides and the fate of As in complex soil systems.

Geochemical characteristics and socioeconomic associations of carbonaceous aerosols in coal-fueled cities with significant seasonal pollution pattern

Carbonaceous aerosols, comprising organic carbon (OC) and elemental carbon (EC), are critical component of fine particulate matter (PM2.5), with diverse impacts on air quality and human health. This study investigated the concentrations and seasonal patterns of carbonaceous species in PM2.5 during both the heating season (January 2021) and non-heating season (July 2021) in three coal-fueled cities in northern China, as well as the differences in carbonaceous aerosols and their associations with socioeconomic parameters in cities situated on either side of the "Hu Line" in China. The results showed that, owing to intensified coal combustion and unfavorable meteorological conditions, levels of OC, EC, and OC/EC ratios were higher in winter compared to summer. Moreover, the presence of dust (DU) and light pollution (LP) days resulted in elevated OC levels but decreased EC levels. The Char-EC/Soot-EC ratios were highest during LP, followed by CL and DU. A source apportionment analysis demonstrated that coal burning, vehicle exhaust, road dust, and biomass burning were the primary contributors to carbonaceous aerosols, as confirmed by diagnostic ratios, Char-EC/Soot-EC ratios, and PCA analysis. Furthermore, our study found that carbonaceous aerosols concentrations and source apportionment primarily varied with diurnal and seasonal trends and different pollution types. Additionally, at the national scale, population density and urban green space exhibited a positive correlation with OC/EC ratios (p < 0.05), while energy consumption per unit of GDP showed a negative correlation (p < 0.05). The observation that OC/EC ratios were lower in coal-fueled cities than in economy-based cities suggests a more severe pollution scenario. These findings highlight the importance of comprehending of the seasonal variation and chemical characteristics of carbonaceous aerosol for understanding air pollution sources and characteristics, which is essential for both air quality management and human health.

[Multiple primary malignancies combined with SWI/SNF complex-deficient gastric cancer: a case report and literature review]

Multiple primary malignancies combined with SWI/SNF complex-deficient gastric cancer is a rare clinical entity and poorly documented. Herein we report a case of this disease in an 81-year-old male patient treated in our hospital. Before the established diagnosis of metachronous multiple primary malignancies, the patient received left lower lobectomy for a spaceoccupying mass in the left lung, which was confirmed by postoperative pathology as early stage lung cancer. SWI/SNF complex-deficiency gastric cancer with metastasis was subsequently detected by gastroscopy, and high-throughput sequencing identified ARID1A and TMB-H gene mutations in the tumor tissues. The patient received chemotherapy combined with immunotherapy but failed to respond to the treatment, and died 13 months later. We conducted a literature review and analyzed the occurrence, pathological and immunohistochemical characteristics, diagnosis, treatment and prognosis of this disease.

Arsenic speciation transformation in soils with high geological background: New insights from the governing role of Fe

In soils, the speciation transformation of As were inherently related to the behaviors of iron (oxyhydr) oxides. It is poorly understood that the effects of the transformation of iron (oxyhydr) oxides coupled with As speciation transformation during dissimilatory Fe(III) reduction (DIR) involving with humic substances (HS) as electron donor or shuttle in soils with high arsenic geological background. In this study, the relationships between the transformation of iron (oxyhydr)oxides and As speciation transformation were investigated according to the response between continuously As speciation monitoring and iron (oxyhydr) oxides identification during DIR in the soils. The results showed that F4 (arsenic incorporated with amorphous iron (oxyhydr)oxides including ferrihydrite and schwertmannite) and F5 (arsenic incorporated with crystalline iron (oxyhydr)oxides including hematite and magnetite) were the main source and sink for As(III)_Dissolved during DIR. During the incubation period, Fe(II) was the dominant driving force for the reduction of As(V) in the water-soil system. The XRD analysis indicated the changes of iron oxides such as ferrihydrite, schwertmannite, hematite and magnetite were closely related to the release and reduction of As, and those iron oxides could play governing roles for As speciation transformation during DIR in soils. Different from the known mechanism in low As concentrations, a limiting effect of As concentration on iron oxides transformation was found in our incubation experiments using soils with high As geological background (∼1000 mg/kg). This work provides new insights for Fe as governing role in As speciation transformation in soils with high arsenic geological background by firstly identifying the corresponding iron (oxyhydr)oxides in operationally defined arsenic speciation incorporated with iron oxides.

Changes in stoichiometric characteristics of ambient air pollutants pre-to post-COVID-19 in China

To prevent the Corona Virus Disease 2019 (COVID-19) spreading, Chinese government takes a series of corresponding measures to restrict human mobility, including transportation lock-down and industries suspension, which significantly influenced the ambient air quality and provided vary rare time windows to assess the impacts of anthropological activities on air pollution. In this work, we divided the studied timeframe (2019/12/24-2020/2/24) into four periods and selected 88 cities from 31 representative urban agglomerations. The indicators of PM_2.5/PM₁₀ and NO₂/SO₂ were applied, for the first time, to analyze the changes in stoichiometric characteristics of ambient air pollutants pre-to post-COVID-19 in China. The results indicated that the ratios of NO₂/SO₂ presented a responding decline, especially in YRD (-5.01), YH (-3.87), and MYR (-3.84), with the sharp reduction of traffic in post-COVID-19 periods (P3-P4: 2.34 ± 0.94 m/m) comparing with pre-COVID-19 periods (P1-P2: 4.49 ± 2.03 m/m). Whereas the ratios of PM_2.5/PM₁₀ increased in P1-P3, then decreased in P4 with relatively higher levels (>0.5) in almost all urban agglomerations. Furthermore, NO₂ presented a stronger association with PM_2.5/PM₁₀ variation than CO; and PM_2.5 with NO₂/SO₂ variation than PM₁₀. In summary, the economic structure, lockdown measures and meteorological conditions could explain the noteworthy variations in different urban agglomerations. These results would be in great help for improving air quality in the post-epidemic periods.

Trends and environmental factors of arsenic in sediments from the five lake ecoregions, China

The behavior and risk of arsenic (As) closely relate to its geochemical fractionation and environmental factors in sediments. The soluble (F1), reducible (F2), oxidizable (F3), and residual fraction (F4) of As were extracted in the sediments from Lake Hulun, Wuliangsuhai, and Dalinor of Inner Mongolia Plateau. Coupled with lakes from Eastern and Northeast Plain, Yunnan-Guizhou and Qinghai-Tibetan Plateau, the responses of As fractions to environmental conditions were investigated according to the spatial distribution of As fractionations in five lake ecoregions at a national scale of China. Generally, F1 was more sensitive to environmental changes, and the pH presented significantly negative effects on the amount of soluble As, while water depth played an important role in regulating the distribution of the fraction F2 and F4. The As pools in surface lake sediments presented a latitudinal zonation due to the gradient effects of climate and anthropogenic activities on nutrient decomposition, and their influence on the capacity of sediments holding As. This work indicated that nutrients played a coordinating role in regulating the impacts of climate and environmental factors on As fractionation in aquatic environments.

Heating events drive the seasonal patterns of volatile organic compounds in a typical semi-arid city

The emission characteristics, source apportionment and chemical behavior of volatile organic compounds (VOCs) are important for strategy-making on ozone (O₃) and fine particulate matter (PM_2.5) control. Based on the continuous observation during four seasons, the seasonal characteristics, chemical reactivity and source apportionment of 116 VOCs species were studied in a typical semi-arid city with no relevant research. The results showed that the annual average concentrations of total volatile organic compounds (TVOCs) in Hohhot was 44.67 ± 46.59 ppbv with the predominant of alkanes and oxygenated volatile organic compounds (OVOCs). The sharp increment of TVOCs were explained by the elevating OVOCs and alkanes in autumn, while alkanes and alkenes in winter. The levels of alkenes presented negative and positive correlations with solar radiation and PM₁₀, respectively. The mixing ratios accounted for 30% (alkanes) and 23% (alkenes and aromatics) of the TVOCs, respectively; while their ozone formation potential (OFP) ~15% and nearly 50% (even 75% in winter), respectively, indicating that the OFP of different VOCs species depends not only on their concentrations but more importantly on their chemical activity in atmosphere. According to the seasonal source apportionment, both the high levels of short-chain alkanes, alkenes and aromatics and the increasing coal sales volume suggested that the combustion sources were the predominant in heating seasons, while solvent uses was extracted as the most predominant during non-heating seasons. In non-heating seasons, the biogenic emission sources, ranking as the second contributor, were significantly higher than heating seasons. Isoprene was the most active biogenic VOCs species, bagging test results showed that deciduous trees were the predominant contributors for isoprene (~99%), while coniferous trees and shrub for monoterpenes (>95%). It will be helpful for understanding the characteristics of VOCs in Chinese national key development areas and informing policy to control semi-arid regional VOCs air pollution.

Factors and pathways regulating the release and transformation of arsenic mediated by reduction processes of dissimilated iron and sulfate

The driving process and explanatory factors regulating the transformation and migration of arsenic (As) mediated by dissimilatory iron reducing bacteria (DFeRB) and sulfate reducing bacteria (SRB) remain poorly understood. The novelty of this study is to explore the driving process and key environmental factors governing As mobilization mediated by DFeRB and SRB based on continuous As speciation and environmental parameter monitoring in a sediment-water system. The results illustrate the reduction process mediated by DFeRB and SRB significantly promotes the reduction of As(V) and the endogenous release of As. However, in the DFeRB and SRB mediated reductions, the main driving process and key explanatory factors that dominate the As mobility are significantly different. DFeRB has significant effects on the reductive dissolution and re-distribution of Fe(III) oxyhydroxides and As-containing Fe(III) minerals and on adsorption-desorption, which in turn influenced the transformation of iron species and the release and ecotoxicity of As. Meanwhile, the environmental factors that affect As mobility depend on Fe²⁺ and Fe³⁺ in DFeRB-induced reduction, presenting two main pathways: the process of As mobilization mediated by DFeRB, and the process influenced by the inorganic phosphorus involved in the competitive adsorption and anion exchange. Significantly different from DFeRB, the effects of SRB on As behavior mainly occur by influencing the adsorbed As, pyrite, and As sulfides in the sediments and through the formation of sulfides during the sulfate reduction. The main pathways of As mobilization reflect the direct effects of SRB, S^2-, and Fe²⁺. In addition, the role of NH₄⁺-N in the driving process of As mobility is more pronounced in SRB-induced reduction. NO₃^--N is an essential factor affecting As mobility, but the effects of NO₃^--N on As lead to non-significant pathways. This work provides insights into the environmental effects of DFeRB and SRB on the biogeochemical cycle of As.

Distribution, sources, and ecological risk assessment of polycyclic aromatic hydrocarbons in the sediments of Daihai Lake in Inner Mongolia, China

Polycyclic aromatic hydrocarbons (PAHs) are typical toxic organic pollutants that can accumulate in sediments and may be toxic to aquatic organisms. In the present study, the contamination level, composition pattern, and sources of sixteen PAHs listed by the United States Environmental Protection Agency were investigated in surface sediments and a sediment core from Daihai Lake, which is located in a typical semiarid area of Inner Mongolia, China, and the ecological risk of these PAHs was assessed. The results show that the total concentration of PAHs in the surface sediments ranged from 204.6 to 344.5 ng/g with an average value of 287.2 ng/g and that compared with other aquatic systems, the level of PAHs in the sediments from Daihai Lake was low. However, a general upward trend was observed for the concentrations of PAHs in the sediment core, which might be related to the increase in human activities in the area. Moreover, the PAH concentrations were significantly positively correlated with the total organic carbon (TOC) content in the sediments, and it is thus inferred that TOC regulates the distribution of PAHs in Daihai Lake. Three-ring and four-ring PAHs were found to be predominant in all the sediment samples, and phenanthrene (Phe) was the most abundant compound. According to the composition of PAHs and the anthracene (Ant)/(Ant+Phe) or fluoranthene (Flt)/(Flt+pyrene (Pyr)) ratios, the PAHs in Daihai Lake mainly originated from the combustion of domestic coal, grass, and wood, and petroleum cannot be ignored as a source considering the growth of industry. Risk assessment based on a comparison of PAH concentrations and the effect range low (ERL) and effect range median (ERM) values demonstrated that acenaphthene (Ace) at 11 sites and fluorene (Flu) at 7 sites had occasional adverse biological effects.

[Expert consensus on the strategy and measures to interrupt the transmission of schistosomiasis in China]

Since 2015 when the transmission of schistosomiasis was controlled in China, the country has been moving towards elimination of schistosomiasis, with the surveillance-response as the main interventions for schistosomiasis control. During the period of the 13th Five-Year Plan, the transmission of schistosomiasis had been interrupted in four provinces of Sichuan, Jiangsu, Yunnan and Hubei and the prevalence of schistosomiasis has been at the historically lowest level in China. As a consequence, the goal set in The 13th Five-Year National Schistosomiasis Control Program in China is almost achieved. However, there are multiple challenges during the stage moving towards elimination of schistosomiasis in China, including the widespread distribution of intermediate host snails and complicated snail habitats, many types of sources of Schistosoma japonicum infections and difficulty in management of bovines and sheep, unmet requirements for the current schistosomiasis control program with the currently available tools, and vulnerable control achievements. During the 14th Five-Year period, it is crucial to consolidate the schistosomiasis control achievements and gradually solve the above difficulties, and critical to provide the basis for achieving the ultimate goal of elimination of schistosomiasis in China. Based on the past experiences from the national schistosomiasis control program and the challenges for schistosomiasis elimination in China, an expert consensus has been reached pertaining to the objectives, control strategy and measures for The 14th Five-Year National Schistosomiasis Control Program in China, so as to provide insights in to the development of The 14th Five-Year National Schistosomiasis Control Program in China.

Stoichiometric characteristics and economic implications of water-soluble ions in PM2.5 from a resource-dependent city

The stoichiometric characteristics of water-soluble ions (WSIs) in PM_2.5, which can be used as an indicator socioeconomic development level, are mostly depending on the sources and formation mechanism of PM_2.5. This work presents the stoichiometric characteristics and socioeconomic linkage of WSIs in PM_2.5 from a resource-dependent city. The relationship between NO₃^-/SO₄^2- and car parc indexes the contribution of mobile emission source. The equivalent ratio of WSIs suggested that aerosol particles were weak acidic due to the deficiency of cations in PM_2.5, which was consistent with the average annual pH (6.27) of precipitation in Wuhai in 2015. NH₄⁺ neutralizes PM_2.5 acidity in clean and polluted days, while Ca²⁺ and NH₄⁺ in dust storm days. Furthermore, the PCA analysis indicated the multi-sources pollution characteristics from Spring to Fall, which was related the small build-up area (only 62.30 km²) and the close-set of various industrial enterprises in Wuhai. The ratios of NO₂/SO₂ may not work effectively to identify the importance of mobile versus stationary pollution emission sources when the heavy emission from the secondary industry, especially the proportion of secondary industry higher than 65% and the ratios of NO₂/SO₂ lower than 0.4. This work contributes to more effective control strategies for PM_2.5 in resource-dependent areas.

Transformation pathways of arsenic species: SRB mediated mechanism and seasonal patterns

Sulfate reducing bacteria (SRB) mediated reduction plays a key role in the biological cycling of As, which inherently associates with the transformation of As species. However, the potential pathways of As species transformation, the predominant driving process and their explanatory factors regulating seasonal As mobility mediated by SRB remains poorly understood. This study explored the possible pathways of seasonal As species transformation mediated by SRB, and identified the predominant driving process and key environmental factors in response to As mobilization in different seasons. SRB-mediated reduction governed the seasonal mobilization of As, significantly promoted reduction of As (V) and endogenous release of As, and exhibited strong seasonal variability. The flux of As(III) and TAs in group SRB in summer were 1.92-3.53 times higher than those during the ice-bound period. The results showed two distinct stages namely release and re-immobilization both in summer and ice-bound period. While As was easier to be gradually transformed into a more stable state in SRB reduction process during ice-bound period. Both in summer and ice-bound period, SRB presented significant regulating effects on As behavior by influencing loosely adsorbed As, pyrite and As sulfides in sediments as well as the formation of sulfide during the process of SRB reduction. The main effecting pathways on As mobilization were the direct effects of SRB, S^2- and Fe²⁺ in summer, but IP was also an important pathway affecting As mobility during ice-bound period. This work provides new insights into mechanisms responsible for seasonal As mobilization.

Geochemical characteristics of rare earth elements in windowsill dust in Baotou, China: influence of the smelting industry on levels and composition

Smelting is one of the main sources of rare earth elements (REEs) in large scale smelting regions that have been neglected before. To provide experimental evidence on the influence of smelting processes on REEs in windowsill dust, this study investigated the concentration, chemical fractions, and spatial distribution of 14 REEs in windowsill dust and assessed the possible influence of smelting processes on the geochemical behavior of these REEs. A total of 46 windowsill dust samples were collected from different locations in Baotou, a typical industrial city for large-scale smelting. The fractions of REEs were analyzed by Tessier sequential extraction analysis. The enrichment factor (EF) was adopted to assess the contribution of anthropogenic emissions of REEs. The loess-normalized REE patterns of windowsill dust are similar to those of the iron ore of the Bayan Obo mine, but differ from those of the local soil. The concentrations of La, Ce, Pr, Nd, and ∑REEs in the residual fraction and total digestion decrease gradually with the increase in distance from the smelter in the downwind direction. These results suggested that the accumulation and fractionation of REEs in windowsill dust are considerably influenced by smelting. The emission of smelting is the main source of REEs for windowsill dust in Baotou.

Employing bacterial mutations for the elucidation of photo-Fenton disinfection: Focus on the intracellular and extracellular inactivation mechanisms induced by UVA and H2O2

The bacterial inactivation mechanisms by solar light and the photo-Fenton process is still a matter of debate. In this study, we bring evidence towards the elucidation of the mechanisms that govern photo-Fenton disinfection at near-neutral pH. With the use of porin-deficient and catalase over-producing E. coli strains, in conjunction with measurements of cell wall oxidation and permeability, we are able to i) highlight the role of the aforementioned components in bacterial inactivation and ii) localize the damages in the intracellular domain, despite the addition of the Fenton reagents in the bulk. We report that H₂O₂ oxidizes cell walls but under light the process is of low significance; UVA initiated an intracellular oxidation process based on excess accumulated H₂O₂, while the UVA+H₂O₂ and UVA+H₂O₂+Fe²⁺ processes have the same effect with light, albeit enhanced, as shown by malondialdehyde (MDA) production and ONPG hydrolysis rates. Finally, compared to the UVA-assisted photo-Fenton process, its solar counterpart is enhanced by the direct UVB effects on bacterial DNA. In conclusion, we have sufficient evidence to postulate that the photo-Fenton process is intracellular and propose the pathways that form the integrated bacterial inactivation mechanism by photo-Fenton.

Seasonal response of the synergism of maternal comorbidities and long-term air pollution exposure on birth outcomes

Air pollution has been considered as one of the most important factors associating with various birth outcomes. However, the seasonal response of maternal comorbidities effects associated with air pollution has not been investigated, especially in the city with distinguish seasonal pattern and long heating seasons. In this work, 69,945 live births were investigated from 2013 to 2016, and the seasonal relationship between air pollution and preterm birth and low birth weight were assessed, as well as the synergism of maternal comorbidities. Exposures of six pollutants were assigned to maternal residences during pregnancy. The potential effect modification by maternal comorbidities on the associations was evaluated between prenatal air pollution and preterm birth (PTB), as well as effects of seasons and trimesters. Adjusting for seasonality, all six pollutants presented seasonal relationship with preterm birth, which CO, PM₁₀, NO₂, and PM_2.5 were with [odds ratio (OR) = 1.035 95% CI: 1.015, 1.055, OR = 1.039 95% CI: 1.034, 1.045, OR = 1.042, 95% CI: 1.029, 1.056 and OR = 1.085 95% CI 1.073, 1.097, respectively] for tenth quartile of 10 μg/m³ range increased in autumn (the beginning of heating season). For O₃, it associated with PTB in winter and spring with OR = 1.113 95% CI: 1.104, 1.123, and OR = 1.155 95% CI: 1.145, 1.165, respectively. The OR increase of PTB for exposure to all six pollutants was higher among women with preeclampsia and gestational hypertension. The associations between ambient air pollution and preterm birth were modified by gestational hypertension and preeclampsia. The seasonal patterns of six studied air pollutants increases the risk of PTB in autumn and winter distinguishably, which may due to the sudden increased concentrations of pollutants emitted by traditional heating. The seasonal response of the synergism of maternal comorbidities and long-term air pollution exposure on birth outcomes is supported by the data sets of preterm birth.

[Surveillance and control strategy of imported schistosomiasis mansoni: an expert consensus]

In 1980s, Biomphalaria straminea, an intermediate host of Schistosoma mansoni, was found in Shenzhen City, Guangdong Province, China, and currently, this snail has colonized in Shenzhen City and spread to peripheral cities involving of Dongguan and Huizhou. Since imported cases infected with S. mamoni have been reported from time to time in China, Mainland China is facing the potential risk of transmission of schistosomiasis mansoni. With the deepening of the opening-up policy, notably the implementation of the Belt and Road Initiative, there is an increase in the risk of transmission of schistosomiasis mansoni in Mainland China. Increasing the understanding on schistosomiasis mansoni, improving the awareness toward schistosomiasis mansoni prevention and control, and identifying, reporting and managing imported cases with S. mansoni infection or pathogen carriers, are of particular importance to prevent the development of entire life cycle of S. mansoni and the resultant schistosomiasis mansoni transmission in China. To protect public health, a consensus has been reached pertaining to the surveillance and control strategy of imported schistosomiasis mansoni by Chinese infectious disease experts and parasitologists, with aims to improve the awareness and capability for the diagnosis, treatment and control of imported schistosomiasis mansoni among Chinese disease control and prevention institutions and medical institutions, and decrease and even eliminate the risk of schistosomiasis mansoni transmission in China.

Increasing risk of congenital anomalies associated with seasonal pattern of air pollution: Differences by maternal comorbidities

To interpret the relationship of the seasonal pattern of air pollution exposure associated with increased risk of congenital anomalies (CA) and the trimester-specific effects. In this work, 55,428 hospital records with 847 doctor-diagnosed CA from July 2013 to December 2016 were collected in Hohhot, China. Maternal exposure to critical air pollutants (SO₂, CO, PM₁₀, O₃, NO₂ and PM_2.5) were estimated using an inverse distance weighted (IDW) method on the basis of the ambient air quality monitoring stations. Logistic regression analysis was employed to determine the association of CA (in terms of odds ratio (OR) and 95% confidence interval (CI)) in three trimesters with heating/none heating season exposure. The results showed that CO exposure was found a significant association with ORs (95% CI) 1.58 (1.09, 2.27) changing from IQR2-3 and 1.40 (1.01, 1.93) changing from IQR3-IQR4 in 1st trimester and 1.51 (1.12, 2.04) changing from IQR2-3 in 2nd trimester, respectively. PM₁₀ also presented significant association with ORs (95% CI) 1.42(1.08, 1.86) changing from IQR3-4 in 2nd trimester. Exposure effects were found more obvious in heating season, i.e. CO exposure levels were associated with the risks of CA with IQR changing ORs (95% CI) of 5.21(2.02, 7.44), 2.24 (1.21, 4.15) and 1.84 (1.10, 3.11) in 1st trimester, respectively; PM_2.5 exposure levels were associated with the risks of CA with IQR changing ORs (95% CI) of 3.76 (1.48, 6.55), 2.45 (1.10, 5.44) and 3.30 (1.63, 6.67) in 2nd trimester, respectively. Our findings suggested some positive associations of pregnancy and CA with maternal exposure to ambient CO and PM_2.5 during the 1st and 2nd trimester after controlling for maternal comorbidities general covariates and other pollutants. PM₁₀ was also found significantly associated with increased risk of CA in 2_nd trimester besides seasons. There was no association found in 3rd trimester.

The role of major functional groups: Multi-evidence from the binding experiments of heavy metals on natural fulvic acids extracted from lake sediments

Fulvic acid (FA) plays a key role in governing the environmental geochemistry behavior of heavy metals. In this work, the roles of major functional groups were investigated based on binding experiments of heavy metals on natural FA extracted from lake sediments. The results showed that the adsorption capacities were ranked as Cu²⁺ > Pb²⁺ >Cd²⁺. The differences of peak area at 3412, 1713, 617and 2430 cm^-1 pre- and post-binding reactions in FTIR spectra suggested that phenolic, carboxyl and nitrogen-containing groups were the major functional groups providing sites binding heavy metals. Moreover, the results of bi-Langmuir model and the ionic strength effects jointly indicated that electrostatic attraction was the key mechanism during the adsorption process. The fitted results of Ligand-binding model suggested that the major functional groups in FA were classified into two types binding sites: weak (i.e. phenolic and carboxyl groups) and strong binding sites (i.e. nitrogen-containing groups). Additionally, there might be p-benzoquinone-like formed in FA which were then reduced to hydroquinone during the adsorption process, corresponding to the changing of peak area at 1614 and 830 cm^-1 in FTIR spectra, the occurrence of Peak C in Fluorescence excitation-emission matrix (EEM) spectra and the ratios of H/C (<1) and O/C (≈1). The organic matter in sediments from Lake Wuliangsuhai presented similar characteristics with terrestrial plants due to the lake characterized by Phragmites australis and Potamogeton pectinatus L. being the dominant species, which shared large proportions of woody tissues as well as waxy hydrocarbons resembling that of terrestrial plants. This work is useful to insight the environmental effects of FA on heavy metals in environment.

Nature differences of humic acids fractions induced by extracted sequence as explanatory factors for binding characteristics of heavy metals

The composition and structure of Humic acid (HA) is so heterogeneous that it brings significant barriers to investigate the interaction between HA and heavy metal ions. The isolation of HA with relatively homogeneity is a key to reveal the binding mechanisms between HA and heavy metals. In this work, ten HA fractions (HAs) were obtained by sequential alkali extraction procedure and nature differences of the extracted HAs were considered as explanatory factors for binding characteristics of Cu²⁺, Pb²⁺ and Cd²⁺. The results indicate that more large molecular weight (MW) HA subunits, less carboxyl and phenolic group contents, weaker aromaticity and polarity were measured with increasing extractions, inducing weaker binding capacity of HAs. Ligand binding and bi-Langmuir models indicated that the sorption capacity and binding affinity of earlier extracted HAs were higher than the latter ones. The peak area changes at 3427, 1599, and 619 cm^-1 pre- and post-adsorption in FTIR spectra suggested carboxyl, phenolic and nitrogen-containing groups were involved in the adsorption process. At the same time, the peak area difference between HAs and HAs-metal (ΔS) of phenolic groups were 8.22-20.50, 6.81-21.11 and 10.66-19.80% for Cu²⁺, Pb²⁺ and Cd²⁺, respectively, ΔS of carboxyl groups 6.64-17.03, 8.96-16.82 and 9.45-17.85% for Cu²⁺, Pb²⁺ and Cd²⁺, respectively, ΔS of nitrogen-containing groups 0.33-0.48, 0.20-1.38 and 0.31-0.59% for Cu²⁺, Pb²⁺ and Cd²⁺, respectively. ΔS of phenolic and carboxyl groups were larger than those of nitrogen-containing groups, implying that these two groups were the predominant binding sites suppliers for metal ions, which were also supported by the results of correlation analysis. This work is helpful to insight the environmental impacts of natural organic matter and the fate of heavy metals in natural environment.

[Arthroscopic treatment for patellar dislocation with lateral retinacular release combined with medial patellofemoral ligament reconstruction]

Objective

To investigate the effectiveness of the arthroscopic lateral retinacular release combined with medial patellofemoral ligament (MPFL) reconstruction for patellar dislocation.

Methods

Between January 2016 and March 2017, 28 cases (32 knees) with patellar dislocation were treated by arthroscopic lateral retinacular release and MPFL reconstruction. There were 6 males (6 knees) and 22 females (26 knees) with an average age of 21 years (range, 17-29 years). The disease duration ranged from 2 days to 2 years (mean, 8 months). Apprehension test of all patients were positive. The preoperative Lysholm score was 68.34±12.26. Anteroposterior X-ray film showed the patellar subluxation or dislocation. The Q angle was (17.67±4.21)° and the distance of tibia tuberosity-trochlear groove was less than 20 mm. The femoral attachment of retinacular were fixed by the interference screws (16 knee) or the anchors (16 knee), respectively.

Results

All incisions healed by first intention. All patients were followed up 6 months. The function of knee joint was significantly improved at 6 months after operation. The Lysholm score was 92.88±6.42 and the Q angle was (12.15±3.68)° at 6 months. There were significant differences in the Lysholm score and the Q angle between pre- and post-operation ( t=-3.408, P=0.006; t=-2.317, P=0.004). Apprehension test of all patients were negative. No knee pain, knee weakness, and patellar dislocation occurred during follow-up. There was no significant difference in the Lysholm score and the Q Angle between the anchor group and interference screw group ( t=-3.254, P=0.820; t=-3.576, P=0.940).

Conclusion

Lateral retinacular release combined with MPFL reconstruction under arthroscopy can effectively improve the function of the knee joint for patients with Q angle less than 20° and TT-TG less than 20 mm, and the early effectiveness is good. There is no significant difference in knee function between the anchor and interference screw internal fixation.

Spatial and historical distribution of organic phosphorus driven by environment conditions in lake sediments

The chemistry of sedimentary organic phosphorus (OP) and its fraction distribution in sediments are greatly influenced by environmental conditions such as terrestrial inputs and runoffs. The linkage of OP with environmental conditions was analyzed on the basis of OP spatial and historical distributions in lake sediments. The redundancy analysis and OP spatial distribution results suggested that both NaOH-OP (OP extracted by NaOH) and Re-OP (residual OP) in surface sediments from the selected 13 lakes reflected the gradient effects of environmental conditions and the autochthonous and/or allochthonous inputs driven by latitude zonality in China. The lake level and salinity of Lake Hulun and the runoff and precipitation of its drainage basin were reconstructed on the basis of the geochemistry index. This work showed that a gradient in weather conditions presented by the latitude zonality in China impacts the OP accumulation through multiple drivers and in many ways. The drivers are mainly precipitation and temperature, governing organic matter (OM) production, degradation rate and transportation in the watershed. Over a long temporal dimension (4000years), the vertical distributions of Re-OP and NaOH-OP based on a dated sediment profile from HLH were largely regulated by the autochthonous and/or allochthonous inputs, which depended on the environmental and climate conditions and anthropogenic activities in the drainage basin. This work provides useful environmental geochemistry information to understand the inherent linkage of OP fractionation with environmental conditions and lake evolution.

Nature differences of fulvic acid fractions induced by extracted sequence as explanatory factors for binding characteristics of Cu2

The isolation of fulvic acid (FA) fractions with relatively homogeneity is a key to reveal the binding mechanisms between FA and heavy metals. In this work, nine FA fractions were obtained using sequential alkali extraction procedure and nature differences of the extracted FA fractions were considered as explanatory factors for binding characteristics of Cu²⁺. The results indicate that the contents of carboxyl and phenolic groups decrease with increasing extractions along with an opposite trend for the content of nitrogen-containing groups. The fitted results of ligand binding and bi-Langmuir models indicate that the binding sites for Cu²⁺ were mainly provided by carboxyl and phenolic groups, which explained the higher sorption capacity and binding affinity of earlier extracted FAs due to its higher contents of carboxyl and phenolic groups. Furthermore, the systemic characterization of FA fractions before and after adsorption indicate the nitrogen-containing groups were gradually showing their contribution in binding Cu²⁺ with increasing extractions. This work is very helpful to insight the environmental effects of natural organic matter and the behavior of heavy metals in natural environment.

Adsorption characteristics of Pb2+ on natural black carbon extracted from different grain-size lake sediments

As a major organic component in aquatic sediments, black carbon (BC) could act as super surface sorbent for contaminants in soils or sediments due to its relatively structured carbon matrix with high degree of porosity and extensive surface area. In this work, the adsorption characteristics of Pb²⁺ were studied using BCs as adsorbents, which were extracted from four particle sizes of sediment from Lake Wuliangsuhai (WLSH), under conditions of different pH, BC content, and ionic strength. The results showed BC content near to 1 % of sediments from WLSH, in which BC1, BC2, BC3, and BC4 composited about 1.8, 1.6, 1.1, and 0.8 % in the sediment fractions of >180, 180-63, 63-32, and <32 μm, respectively. The specific surface area and the Pb²⁺ sorption capacity were increased with decreasing the particle size of BCs. Correspondingly, the adsorption percentage of Pb²⁺ increased with increasing initial pH and BC content but declined as the increase of ionic strengths. The Pb²⁺ sorption capacity was reached maximum at pH 5-6. Compared pre- to post-sorption BCs by SEM-EDS and FTIR, although the carboxyl (C=O) and phenol (OH) groups on BC fractions contributed to Pb²⁺ sorption, the main adsorption mechanism of BCs was the surface sorption at pH <6. Relatively, the contribution of BCs accounted for about 18 % of Pb²⁺ sorption capacity on sediments. This work is helpful to understand the environmental effects of different size fractions BCs extracted from natural sediments.

Binding characteristics of Cu2+ to natural humic acid fractions sequentially extracted from the lake sediments

Humic acids (HAs) determine the distribution, toxicity, bioavailability, and ultimate fate of heavy metals in the environment. In this work, ten HA fractions (F1-F10) were used as adsorbent, which were sequentially extracted from natural sediments of Lake Wuliangsuhai, to investigate the binding characteristics of Cu²⁺ to HA. On the basis of the characterization results, differences were found between the ten extracted HA fractions responding to their elemental compositions and acidic functional groups. The characterization results reveal that the responses of ten extracted HA fractions to their elemental compositions and acidic functional groups were different. The O/C and (O + N)/C ratio of F1-F8 approximately ranged from 0.66 to 0.53 and from 0.72 to 0.61, respectively; the measured results showed that the contents of phenolic groups and carboxyl groups decreased from 4.46 to 2.60 mmol/g and 1.60 to 0.58 mmol/g, respectively. The binding characteristics of Cu²⁺ to the ten HA fractions were well modeled by the bi-Langmuir model; the binding behavior of Cu²⁺ to all the ten HA fractions were strongly impacted by pH and ionic strength. The FTIR and SEM-EDX image of HA fractions (pre- and post-adsorption) revealed that carboxyl and phenolic groups were responsible for the Cu²⁺ sorption on the ten sequentially extracted HA fractions process, which is the same with the analysis of the ligand binding and bi-Langmuir models Accordingly, the adsorption capacity of the former HA fractions on Cu²⁺ were higher than the latter ones, which may be attributed to the difference of carboxyl and phenolic group contents between the former and latter extracted HA fractions. Additionally, the functional groups with N and S should not be neglected. This work is hopeful to understand the environmental effect of humic substances, environmental geochemical behavior, and bioavailability of heavy metals in lakes.

Responses of Organic Phosphorus Fractionation to Environmental Conditions and Lake Evolution

Geochemical fractionation is used to assess the significance of environmental factors on organic phosphorus (OP) pools in sediments. Labile, moderately labile, and nonlabile OP pools in the sediments from Lake Hulun, Inner Mongolia, were fractionated, and their responses to environmental conditions and lake evolution were investigated based on the spatial and vertical distribution of OP fractionations. In light of the recalcitrant characteristics of organic matter (OM) in different environmental conditions, the pH presents significant negative effects on the amount of labile OP, while water depth shows an important role in regulating the distribution between the moderately labile and nonlabile OP pools. A latitudinal zonation in the distribution of OP pools in surface sediments from different lakes was apparent with this zonation likely linked to the gradient effects of climate and anthropogenic activities on OM decomposition and thereby on the sediments capacity to hold phosphorus. These results show that OM plays a role in governing the impacts of weather and environmental factors on OP fractionation in aquatic environments. This work suggests that OP pools in the sediment core could be used as an archive for environmental conditions and lake evolution.

Processes and their explanatory factors governing distribution of organic phosphorous pools in lake sediments

The amount of organic phosphorus (OP) and its distribution among different pools in lake sediments depends on biotic and abiotic processes driving the OP fractionation. Key environmental factors governing these transformations processes between OP fractionations in sediments were studied on the basis of geochemical characteristics of OP pools in relation to environmental factors in the sediments. The results illustrate that the factors influencing the accumulation or depletion of different OP pools were intrinsically dependent on the composition of the deposited organic matter (OM). During the mineralization of the OM the microorganisms excrete the enzyme alkaline phosphatase, accelerating the OP hydrolysis, and thereby setting the grounds for the bacterially-mediated oxidation of OM. There are two main degradation products of the labile OP pool (LOP) and the moderately labile OP pool (MLOP): Either the OP is transformed to a dissolved organic or inorganic P form, and thereby released to water column, or OP is transformed to a non-labile OP pool and stored in the sediments. A comparative study showed that oxy-hydroxides of iron (Fe) and aluminum (Al) only played an important role in influencing OP fractionation in Lake Wuliangsuhai, while the complexation reactions of OP with calcium ions and sorption to its minerals are key factors governing the OP fractionation in the two alkaline lakes. It is worth noting that a significant correlation between the Fe-P pool and the pools of LOP and MLOP indicates that the degradation of the rather labile OP pools are highly dependent on the iron redox reaction.

Distribution characteristics of organic phosphorus in sediments from Lake Hulun, China

The amount of organic phosphorus (OP) and its distribution among different pools in lake sediments depend on biotic and abiotic processes driving OP fractionation. The key abiotic factors governing these transformation processes between different OP fractions in sediments were studied on the basis of distribution characteristics of OP pools in sediments from Lake Hulun (HLH). The results showed the order of the size of OP pools in the surface sediments from Lake Hulun to be: Re-OP (residual OP) ≫ FAOP (fulvic acid fraction) ≥ HCl-OP (OP extracted by HCl) > HAOP (humic acid fraction) ≫ LOP (labile OP); lower concentrations of LOP were found in lake surface sediments with high pH (pH > 9) of lake overlying water indicating a governing role of pH in LOP degradation in an aquatic environment. The pattern of total OP (TOP) spatial distribution showed an obvious decreasing trend from the west to the east lake districts in surface sediments from HLH, which was attributed to the inputs of dust and dry grass driven by the prevailing wind and the finer grain size in the west lake districts. However, the spatial distribution pattern of dissolved OP (DOP) in overlying water, which presented different trends with TOP and total organic carbon (TOC) in surface sediments, indicated that the biological factors and terrestrial inputs showed a joint influence on DOP distribution in HLH. The higher levels of Re-OP and lower levels of HCl-OP observed in HLH may reveal that calcium ions and their minerals were the key governing factors of OP fractionation in sediments from HLH. This work revealed the main abiotic process or mechanism driving OP fractionation in the aquatic environment helping to understand the geochemical information archived in OP pools in lake sediments.

Land use as an explanatory factor for potential phosphorus loss risk, assessed by P indices and their governing parameters

The total level of phosphorus (P) and the distribution of P pools in the topsoil are significantly affected by the excessive application of mineral and organic fertilizers connected with intensive agriculture. This leads to an increased potential risk for P loss, and then contributes to freshwater eutrophication. Soil test P (STP), P sorption index (PSI) and degree of P saturation (DPS) are commonly applied as proxies for assessing the risk of P loss. Although conceptually based, the empirical relationships between these operationally defined proxies and the actual P flux exhibit large spatial variations. Herein, a comprehensive synoptic study and monitoring of soil has been conducted in a watershed in north-eastern China. A set of conventional indicators for soil P loss risk were measured along with the main P pools, P sorption indices, texture, organic matter, as well as Fe and Al oxides and other mineral compositions. Moreover, detailed soil P speciation was conducted using phosphorus nuclear magnetic resonance ((31)P NMR) spectroscopy. In addition, phosphatase activities in the soils were determined for each land use soil category. The results reflected that the soil content of total P, total inorganic P and STP increased significantly following the order of increasing management intensity. STP, being strongly coupled to the application of P fertilizers, was a strong explanatory factor for the spatial differences in DPS - both between and within different land uses. The dominant inorganic and organic P species in the soils were orthophosphate and monoester-P, respectively. Their contents were oppositely correlated with the degree of management influence, with the amount of orthophosphate positively related. Alkaline phosphomonoesterase (AlP) represented the highest activities among the four representative phosphatases, i.e. enzymes that hydrolyze organic P - releasing labile orthophosphate. Orchard soils were found to contain the highest levels of monoester P as well as high AlP activities. This indicates a strong capacity to produce labile orthophosphate. Our results suggest that the type of land use can be employed as a general explanatory factor for considering the potential high risk of loss of P. Regionalized P loss parameters will further improve the accuracy of risk assessment.

Environmental geochemistry of dissolved and biogenic silicon and its nutrient limitation effects in an inland lake, China

Silicon (Si) processing and retention play a key role in nutrients biogeochemistry cycling in aquatic environment. In order to interpret the possibility of Si limitation, multivariate analysis was performed based on stoichiometric nutrients balance, distribution characteristics of dissolved silicon (DSi) and biogenic silica (BSi), adsorption behavior, and response relation of BSi with paleoenvironment in water-sediment system of Lake Daihai. The spatial distributions of DSi and BSi in the water-sediment system indicated that terrigenous inputs (such as the weathering of rock and soil in the drainage basin) was the main sources of Si. Meanwhile, grain sizes of sediments, water hydrogeochemistry, and space competition between diatoms and submergent or emerging plants also played important roles in regulating BSi spatial distributions. The sediments from the lake presented obvious releasing trend of Si at low initial concentrations (≤ 3 mg/L) in adsorption experiments, indicating that the sediments were the source of Si to the overlying water. Furthermore, the good response relation between BSi and paleoenvironment observed in the sediment profiles from Lake Daihai indicated that the main reasons for Si limitation to siliceous plankton were different during different periods. The multi-evidences of distribution characteristics, stoichiometric nutrient balance, adsorption behaviors, and response to paleoenvironment were jointly indicative of Si limitation on the primary production of siliceous plankton in Lake Daihai.

Effects of environmental factors on nutrients release at sediment-water interface and assessment of trophic status for a typical shallow lake, northwest China

Surface sediment and water samples were collected from Daihai Lake to study the biogeochemical characteristics of nitrogen and phosphorus, to estimate the loads of these nutrients, and to assess their effects on water quality. The contents and spatial distributions of total phosphorus (TP), total nitrogen (TN), and different nitrogen forms in sediments were analyzed. The results showed that concentrations of TN and TP in surface sediments ranged from 0.27 to 1.78 g/kg and from 558.31 to 891.29 mg/kg, respectively. Ratios of C:N ranged between 8.2 and 12.1, which indicated that nitrogen accumulated came mainly from terrestrial source. Ratios of N:P in all sampling sites were below 10, which indicated that N was the limiting nutrient for algal growth in this lake. Effects of environment factors on the release of nitrogen and phosphorus in lake sediments were also determined; high pH values could encourage the release of nitrogen and phosphorus. Modified Carlson's trophic state index (TSI(M)) and comprehensive trophic state index (TSI(C)) were applied to ascertain the trophic classification of the studied lake, and the values of TSI(M) and TSI(C) ranged from 53.72 to 70.61 and from 47.73 to 53.67, respectively, which indicated that the Daihai Lake was in the stage of hypereutropher.

Distribution characteristics and potential ecological risk assessment of heavy metals (Cu, Pb, Zn, Cd) in water and sediments from Lake Dalinouer, China

The concentrations of Cu, Pb, Zn and Cd were measured in water and sediment to determine their distribution characteristics and potential ecological risks of the Lake Dalinouer. The results revealed that the dominate form of Cu, Pb, Cd and Zn in surface sediments respectively were organic sulfides, Fe-Mn oxides, carbonates and Fe-Mn oxides, with a mean content of 4.28mgkg(-1), 0.76mgkg(-1), 7.84μgkg(-1) and 1.77mgkg(-1), respectively; the concentrations of bio-available metals had an increase tendency from the northeast to the southwest part of this lake. Acid volatile sulfides (AVS) and simultaneously extracted metal (SEM) were used to predict the potential bioavailability of heavy metals. The horizontal distribution of AVS (0.15-2.4μmolg(-1), mean 0.53μmolg(-1)) in surface sediments shows an increasing trend from southwest to northeast of the lake, whereas SEM (0.02-0.99μmolg(-1), mean 0.37μmolg(-1)) had an opposite pattern. The relative high salt and pH which restrained the bioactivities of sulfate-reducing bacteria (SRB) were the main controlling factor in AVS concentrations. The vertical variation of AVS concentration in sediment core increased with depth and different from SEM. Potential ecological risk index (PERI) and geo-accumulation index (Igeo) were used to assess heavy metals accumulation. The results indicated that moderate contamination of most heavy metals was prevalent and presented a decreased trend from southern to northern of the lake, and element Cd emerged the greatest potential ecological risk. The pollution of heavy metal in the southern of the Lake Dalinouer should be taken into consideration seriously.

[The significance of Titin antibody in diagnosing myasthenia gravis with thymoma]

OBJECTIVE

To investigate the clinical significance of Titin antibody (Titin-ab) in diagnosing myasthenia gravis with thymoma (MGT).

METHODS

Titin-ab and acetylcholine receptor antibody (AChR-ab) in the sera of 73 MGT patients with different thymic pathological patterns and 58 MG patients without thymoma (NTMG) were detected by ELISA.

RESULTS

The positive rate of Titin-ab in MGT group was 76.7%, significantly higher than those of NTMG group, other neurologic diseases group and healthy control group (P < 0.01). The sensitivity of Titin-ab in diagnosis of MGT was significantly lower than that of CT scan or MR of thymus (P < 0.05), but the specificity of Titin-ab in diagnosis of MGT was significantly higher than that of CT scan or MR of thymus (P < 0.05). The positive rate of Titin-ab was mainly related to the thymic pathology and was the highest in the thymic epithelial thymoma (TET) subgroup (95.1%). There was no significant correlation between the positive rate of Titin-ab and the Masaoka's stage of thymoma (P > 0.05). The titer of Titin-ab was highly correlated to the titer of AChR-ab in MGT group (r = 0.496, P < 0.01), but not in MGH group (r = 0.385, P > 0.05).

CONCLUSION

Detection of Titin-ab is a rather sensitive, specific, handy method in diagnosis of MGT (especially TET). It may play an important role in the pathogenesis of MGT.

[Study on the level of plasma calcitonin gene-related peptide and adrenomedullin in subjects with primary osteoporosis]

OBJECTIVES

To explore if there is any change of the level of plama CGRP and ADM in primary osteoporosis.

METHODS

75 female subjects complaining of back pain, aged from 34-70 years, were included in present study. The plasma level of CGRP and ADM was determined by radioimmunoassay. The bone mineral density (BMD) of lumber spine and hip of these patients was also examined by dual-energy X-ray absorptiometry (DEXA). According to the WHO osteoporosis criteria, these patients were divided into three groups: normal BMD (as control), osteopenia and osteoporosis.

RESULTS

Plasma level of CGRP and ADM of lumbar osteoporosis are 37 ng/L +/- 7 ng/L and 50 ng/L +/- 11 ng/L respectfully, while those of lumber osteopenia are 38 ng/L +/- 7 ng/L and 49 ng/L +/- 11 ng/L, they are significantly higher than those of normal lumber bone mineral density, which are 29 ng/L +/- 6 ng/L and 38 ng/L +/- 8 ng/L(F = 5.60 or 9.60, P < 0.05 or 0.01). The plasma level of ADM of hip and ward's osteoporosis (49 ng/L +/- 13 ng/L and 49 ng/L +/- 11 ng/L) is also higher than that of the control (F = 5.43 and 4.66, P < 0.05). Group of lumbar osteopenia also has higher level of CGRP and ADM than the control. (37 ng/L +/- 7 ng/L) and 38 ng/L +/- 6 ng/L, P < 0.05).

CONCLUSIONS

Plasma level of CGRP and ADM is significantly increased in subjects with osteoporosis. CGRP and ADM may play a role in the mechanism of etiology of primary osteoporosis.

[Relationship between growth potential of pine, population density of Monochamus alternatus and pathogenicity of Bursaphlenchus xyloophilus]

The results showed that the growth potential of pine (x) is negative related to the population density of Monochamus alternatus (y) and the pathoyenecity of Bursaphlenchus xyloophilus (z). But the population density of Monochamus alternatus is positively related to the pathogenicity of Bursaphlenchus xyloophilus. Three linear equations regression line were established as y = 1793.771 - 16404.47x, z = 31.80989 - 241.9274x, y = -407.611 + 70.51478z. Correlation coefficient is -0.8139, -0.8770 and +0.9864 respectively.

[In vitro studies on the bioactive materials released by lung fibroblasts in experimental pulmonary fibrosis]

OBJECTIVES

The purpose of the present study was to clarify the consecutive changes and roles of hyaluronan (HA), interleukin-8 (IL-8) and collagen production by lung fibroblasts in the course of pulmonary fibrosis.

METHODS

Quantitative and comparative assessments of the HA, IL-8 and collagen (presented by hydroproline; HYP) levels in lung fibroblast-conditioned media were made at various stages during the development of bleomycin-induced pulmonary fibrosis in rats.

RESULTS

In lung fibroblast-conditioned media of bleomycin-treated animals: (1) The HA levels increased significantly on day 1, peaked on day 3, and then gradually declined and returned to control values on days 14 - 28. (2) The IL-8 levels strikingly increased on day 1, reached the peak values on day 7, thereafter, gradually decreased, regained control values by day 28. (3) The collagen levels increased significantly on day 7, peaked on day 14, and then gradually declined, However, remained significantly above normal values on day 28. (4) In bleomycin group, the HA and IL-8 levels both significantly correlated to cell components in BALF.

CONCLUSIONS

The lung fibroblasts were activated, produced increased HA and IL-8, and were the main source of HA and IL-8 within the lung in the early stage of pulmonary fibrosis; increased HA and IL-8 synthesis of lung fibroblasts might reflect the intensity of alveolitis and the disease activity; The excessive collagen deposition within the lung primarily occurred at the middle stage of pulmonary fibrosis.

[Studies on pulmonary fibrosis induced by interstitial macrophages]

OBJECTIVE

To evaluate the role of interstitial macrophages (IMs) in modulating the proliferative capacity of fibroblast(FB).

METHOD

IMs isolated by collagenase IA digestion of disaggreted lung tissues from bleomycin-treated rats were studied in this regard. The culture supernatants of alveolar macrophages(AMs) and of IMs were added to culture media of FBs.

RESULT

The releases of growth factors by the two sub-populations of macrophage were already elevated on 1st day following bleomycin instillation, and peaked on 7th day at a level nearly 3-fold above that of control groups(IM 342%, AM 332%, P < 0.01), the proliferative capacity was correlated well with the levels of TNF alpha and PDGF (r = 0.657, 0.713, P < 0.01).

CONCLUSION

Not only AMs, but also IMs could release growth factors to modulate the proliferation of FBs in vitro. IMs might be of more significance in maintenance of the process of pulmonary fibrosis because of its proximity to FBs.

Homozygous deletion of the p16/MTS1 gene in pediatric acute lymphoblastic leukemia is associated with unfavorable clinical outcome

The p16 gene (MTS1, CDKN2, p16INK4A, CDKI) encoding an inhibitor of cyclin-dependent kinase 4 (cdk4) has been found to be deleted in various types of tumors, including leukemia, and is thought to code for a tumor suppressor gene. Our preliminary findings on eight pediatric patients with acute lymphoblastic leukemia (ALL) suggested that the survival of patients carrying a homozygous p16 gene deletion was significantly inferior to that of those without a deletion. The present study on 48 patients tested the hypothesis that the clinical outcome for pediatric ALL patients is correlated with the presence or absence of the p16 gene. Overall, nine of 48 children (18.3%) carried a homozygous p16 deletion. Such deletions were significantly more common (P = .003) among T-ALL patients (five of eight, 62.5%) than among precursor-B-ALL patients (four of 40, 10.0%). Of nine patients exhibiting p16 deletions, eight (88.9%) were classified as high-risk patients by the recognized prognostic factors of age, white blood cell count, and T-cell phenotype. The 4-year event-free survival in the study population as a whole was 72.7%. Without adjustment for other risk factors (univariate model), the presence of a homozygous p16 deletion was associated with a markedly increased probability of both relapse (P = .0003) and death (P = .002). These findings raise the question of whether the p16 deletion itself confers an increased risk of relapse after adjusting for the known risk factors. In this analysis, the estimated risk multiplier factor for relapse in patients carrying the p16 deletion was 14.0 (P = .0004) and for the risk of death 15.6 (P = .0008). We therefore conclude that the presence of a homozygous p16 deletion may well be an important risk factor for both relapse and death in childhood ALL, and that its prognostic effect is not a consequence of confounding by other factors already known to influence outcome in this disease.

[The influence of basement membrane matrix on the attachment of human gingival epithelial cell to titanium: a scanning electron microscopic study]

In order to investigate the factors which could enhance the integrity of the biological seal between implant and epithelial cells, basement membrane matrigel was coated on the surface of smooth pure titanium. SEM observations showed that the spreading of primary cultured human gingival epithelial cells on Matrigel coated titanium surface was better than that of control groups on the third and the sixth day. This result suggests that the attachment of human gingival epithelial cells to titanium can be enhanced by the basement membrane matrigel.

[Frequency of medical consultation as reflected in 2 representative surveys: DHP-Survey and EVaS-Study (German Cardiovascular Disease Prevention and Survey of Ambulatory Care)]

The frequency of patient-doctor contacts in outpatient care is determined via two representative inquiries supplying complementary perspectives. They concern, on the one hand, a sample of contacts in the consultation room, and, on the other hand, contacts as stated in a population-based survey. In the 25-69 years age bracket, both surveys yielded a contact incidence of 2 to more than 5 contacts per person and quarter of a year. The figure is higher in women than in men. Both surveys agree very well if the consultation-room survey is limited to personal contacts between the doctor and the patient. The distribution of contacts over specialties is similar in both surveys. Compared to other countries, the frequency of outpatient consultations is high in the Federal Republic of Germany. Periodic surveys help to get insight into frequency and structure of medical services.

[Rapid diagnosis of experimental tumor by FITC-Con A lectin--a comparative study of smear and section specimens]

FITC-Con A staining as a rapid diagnostic method for tumor cells was applied to the tumors smeared on glass slide and section specimens to evaluate the reactivity with FITC-Con A. Good staining results were obtained in smear specimens with clear fluorescence on the membrane of tumor cells. Con A and LCH lectins bound well with tumor cells to produce strong fluorescence in comparison with PEA and DBA. It indicates that tumor cells expressed dominantly the receptors of alpha-D-glucose and alpha-D-mannose sugar chain on the membrane of tumor cells. From these results it was concluded that FITC-Con A staining method applied to smear specimens is more advantageous in the rapidity and the simplicity for tumor cell diagnosis than section specimen method.