Biomedical subjects

Maoyong Song

Publications and source records attributed to Maoyong Song.

9 recordsLinked to original sources

PubMed2026

Thermal analysis techniques for microplastic mass quantification: Methodological challenges and standardization needs.

Microplastics (MPs, 1 μm-5 mm) and nanoplastics (NPs, <1 μm) are ubiquitous contaminants requiring standardized quantification methods. This systematic review evaluates thermal analysis techniques for mass-based MP detection, including pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), thermogravimetry-MS (TGA-MS), thermal extraction desorption-GC-MS (TED-GC-MS), and differential scanning calorimetry (DSC). Database searches (Web of Science, from inception to December 1, 2025) following PRISMA guidelines identified studies across seven environmental matrices (water, soil/sediment, atmosphere, biota, human tissues). We identify critical standardization gaps: inconsistent marker ion selection, unvalidated conversion factors for tire and road wear particles (TRWPs), and the absence of certified reference materials for complex matrices. Py-GC-MS demonstrates versatility but suffers from lipid interference in biological samples; TED-GC-MS offers superior sensitivity (sample capacity ∼200× Py-GC-MS) but lacks real-time chromatographic monitoring. To advance data comparability, we propose: (i) harmonized ion selection hierarchies based on specificity-sensitivity balance, (ii) matrix-specific TRWP quantification protocols, and (iii) inter-laboratory validation using environmental reference materials. This review provides a methodological roadmap for standardizing thermal analysis in MP research.

Humans↗

PubMed2006

Ecological risk assessments of endocrine disrupting organotin compounds using marine neogastropods in Hong Kong.

As active ingredients of anti-fouling paints that are widely used on ship hulls, organotin compounds, in particular tributyltin (TBT), are well-known endocrine disruptors causing sex changes in marine organisms and widespread in coastal waters and sediments worldwide. In this study, a comprehensive ecological risk assessment (ERA) of organotins was conducted in Hong Kong waters through determining the imposex status, sex ratio and tissue burdens of these compounds in the neogastropods, Thais clavigera and Thais luteostoma collected from 29 coastal sites. We also investigated the historical trend of organotin effects on these gastropods, and performed a probabilistic ERA based on tissue burden of TBT in the animals. Our results demonstrated that imposex indices were positively correlated with the body burden of organotins in the gastropods. Across all sites, the sex ratio (female:male) decreased significantly with increasing imposex levels or tissue burden of organotins, implying that such pollutants can result in a male-biased population, potentially leading to local extinction in extreme cases. Based on the ERA, 5.4% of all populations of T. clavigera are at risk due to exposure to TBT; the risks include growth inhibition, impairment of immune functions and reduced fitness. Seriously impacted areas included Aberdeen, Repulse Bay, Butterfly Beach, Mui Wo and Ha Mei Wan. A comparison with historical data revealed that there had been some improvement in the areas with low marine traffic, and distant from the major harbour/port. This could partly be due to the restriction on the use of TBT on small vessels (<25m in length) since 1992. Nevertheless, the organotin contamination still remains severe in areas with high marine traffic or adjacent to large harbours/ports. In particular, the situation in the northeastern waters of Hong Kong has been getting worst since 1996 that is probably associated with the rapid development of the cargo container port at Yantian in China.

Animals↗

PubMed2006

Determinations of dioxinlike activity in selected mollusks from the coast of the Bohai Sea, China, using the H4IIE-luc bioassay.

Extracts of mollusks collected from eight cities along the coast of the Bohai Sea, China, were used to determine dioxinlike activity using an in vitro bioassay approach. Dioxinlike activity of total extracts was detected by measuring luciferase activity in a stable transfected rat hepatoma cell line, H4IIE, containing an aryl hydrocarbon receptor (AhR)-responsive element linked to a luciferase reporter gene. Luciferase activity was expressed as a percentage of the maximum response observed for 2,3,7,8-TCDD (% TCDD(max)). All mollusk samples elicited significant dioxinlike activity except those from Dalian (N1). The greatest magnitudes (+/-SD, data ex N1) of activity observed for these extracts ranged from 4.88+/-0.48% to 11.38+/-1.43% TCDD(max). The mean activity was 7.37+/-1.85% TCDD(max). Concentrations of TCDD-EQs in mollusk extracts were from 227.4 to 547.5 pg g(-1) lipid. The cytotoxic effect of the mollusk extracts on cells was assessed at the same time. Six of the mollusk extracts (N2, N3, N4, S1, S2, and S4) caused noticeable growth inhibition over the exposure period at concentrations higher than 0.33% of the extracts concentrations (0.83 microL extract well(-1)). All the dilutions of sample N1 were cytotoxic to the H4IIE cells.

Animals↗

PubMed2006

Measurement of estrogenic activity in sediments from Haihe and Dagu River, China.

Sediments from two rivers in China, the Haihe and Dagu Rivers, were examined for estrogenic activity using an estrogen receptor (ER)-mediated in vitro bioassay system. ER-active compounds were isolated from sediments by Soxhlet extraction, and the crude extracts were fractionated using a florisil column into three fractions. The estrogenic activity of each extract was detected by measuring luciferase activity in the human breast cancer cell line MCF-7 transfected with a luciferase receptor gene. Significant estrogenic activity was observed in each total extract. The 17beta-estradiol equivalents (E2-EQs) ranged from 8.24 to 95.28 ng E2 g(-1) dw. As a result, the relative estrogenic potencies of three fractions in this study descended in the order of Fraction 3>Fraction 2>Fraction 1. The results of the bioassay analysis indicated the heavy pollution status of these sites with estrogenic contaminants. In this study, five selected chemicals, the natural estrogens 17beta-estradiol (E2) and estrone (E1), and the xeno-estrogens 4-octylphenol (OP), 4-nonylphenol (NP), and Bisphenol A (BPA) were also analyzed using the in vitro bioassay. The estrogenic activity of these chemicals were E2>E1>NP>OP>BPA.

Biological Assay↗

PubMed2006

Vitellogenic effects of 17beta-estradiol in male Chinese loach (Misgurnus anguillicaudatus).

Male Chinese loaches (Misgurnus anguillicaudatus) were exposed to 17beta-estradiol (E2) in the ambient water at nominal concentrations of 0.5, 1, 5 and 10 mug/L continuously for 8 weeks using a semi-static system. The gonadosomatic index (GSI), total plasma protein, total plasma calcium, magnesium and zinc, and plasma vitellogenin (Vtg) were determined as test endpoints. Our results indicate no significant changes in the GSI between exposed and control groups (P<0.05). All exposure concentrations of E2 dramatically induced the production of Vtg within 7 days. The vitellogenic response of male loach was time- and dose-dependent. At higher concentrations of E2 (5 and 10 microg/L), total plasma protein, total plasma calcium, and total plasma magnesium presented a significant time- and dose-dependent increase, and the three parameters were significantly correlated with plasma Vtg. We conclude that Chinese loaches are sensitive to estrogenic compounds and may be chosen as potential sentinel species in field and laboratory studies. In addition, total plasma protein, total plasma calcium, and total plasma magnesium can be used as indirect indicators to predict Vtg levels in estrogenized Chinese loach.

Animals↗

PubMed2006

Perfluorooctanesulfonate and related fluorochemicals in human blood samples from China.

Perfluorooctanesulfonylfluoride (POSF)-based compounds have been manufactured and used in a variety of industrial applications. These compounds degrade to perfluorooctanesulfonate (PFOS) which is regarded as a persistent end-stage metabolite and is found to accumulate in tissues of humans and wildlife. PFOS, perfluorohexanesulfonate (PFHxS), perfluorooctanoate (PFOA), and perfluorooctanesulfonamide (PFOSA) have been found in human sera from the United States. In this study, concentrations of PFHxS, perfluorobutanesulfonate (PFBS), PFOS, perfluorohexanoic acid (PFHxA), PFOA, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA), and PFOSA were measured in 85 samples of whole human blood collected from nine cities (eight provinces) in China, including Shenyang (Liaoning), Beijing (Hebei), Zhengzhou (Henan), Jintan (Jiangsu), Wuhan (Hubei), Zhoushan (Zhejiang), Guiyang (Guizhou), Xiamen (Fujian), and Fuzhou (Fujian). Among the 10 perfluorinated compounds (PFCs) measured, PFOS was the predominant compound. The mean concentration of PFOS was greatest in samples collected from Shenyang (79.2 ng/mL) and least in samples from Jintan (3.72 ng/mL). PFHxS was the next most abundant perfluorochemical in the samples. No age-related differences in the concentrations of PFOA, PFOS, PFOSA, and PFHxS were observed. Gender-related differences were found,with males higher for PFOS and PFHxS, and females higher in PFUnDA. Concentrations of PFHxS were positively correlated with those of PFOS, while concentrations of PFNA, PFDA, and PFUnDA were positively correlated with those of PFOA. There were differences in the concentration profiles (percentage composition) of various PFCs in the samples among the nine cities.

Adolescent↗

PubMed2005

AhR-active compounds in sediments of the Haihe and Dagu Rivers, China.

Total concentrations of compounds that can cause activation of the aryl hydrocarbon receptor (AhR) in extracts of river sediments from various locations in the Haihe and Dagu Rivers, Tianjin, China were determined by use of the in vitro H4IIE-luc cell line. AhR-active compounds were isolated from sediments by Soxhlet extraction, and the crude extracts were fractionated using a Florisil column into three Fractions. The response of samples was compared to the TCDD standard and expressed as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalents (TCDD-EQs). Significant dioxin-like activity was observed in each sample. The TCDD-EQs in crude extracts of sediments (SCEs), as determined with the bioassay were 2-4 times greater than the sum of the TCDD-EQs of the eluent from fractions separated with a Florisil column. The results also showed that Fractions 2 and 3 contained most of the AhR-mediated activity. The results obtained by using the bioassay were compared with those of previous measurements of the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) and the structurally-similar AhR-active polychlorinated biphenyls (PCBs). It was determined that sediments from the Dagu River contained greater concentrations of TCDD-EQ than did sediments from the Haihe River except at Jingangqiao (location R3), which is associated with industrial activities in the adjacent densely populated area. The concentrations of TCDD-EQs, based on the EC20 and the relative potency ranges, of SCEs ranged from 330 to 930 and 1200 to 13,900 pg TCDD-EQ g(-1) dry wt in Haihe and Dagu Rivers, respectively.

Animals↗

PubMed2005

Separation and detection of vitellogenin in fish plasma by capillary zone electrophoresis.

A method for coupling capillary zone electrophoresis (CZE) with rapid membrane chromatography purification (RMCP) was established for the analysis of vitellogenin (VTG) in male fish plasma induced with 17ss-estrodiol. CZE analyses of purified VTG were performed in a buffer containing 25 mM sodium borate (pH 8.4). A 50 microm i.d. fused-silica capillary was used for separation and the detection was carried out by UV-diode array at 214 nm. Inter- and intra-assay variabilities of the proposed method were less than 10.06 and 1.95%, respectively. The method has good linear relationship over the scope of 15-2250 microg/ml with a correlation coefficient of R2 = 0.9965 and a detection limit of 7.0 microg/ml. The established CZE method was also applied to directly separate and identify VTG from fish plasma. The results indicated this method could minimize interferences from plasma proteins, allowing the detection of at least 62.5 microg/ml of VTG proteins in total proteins. This is a rapid and easy method to determine the quantity and purity of VTG compared to Bradford method and SDS-PAGE.

Animals↗

PubMed2005

Development and validation of an enzyme-linked immunosorbent assay for vitellogenin in Chinese loach (Misgurnus angaillicaudatus).

A competitive enzyme-linked immunosorbent assay (ELISA) was developed for the quantification of vitellogenin (Vtg) in the plasma of Chinese loach (Misgurnus angaillicaudatus). Vtg was isolated by anion exchange membrane chromatography from the plasma of 17beta-estradiol (E(2))-treated loach. Polyclonal antibody against Vtg was raised in rabbits, and the specificity of the antibody was assessed by Western blotting analysis. No cross-reactivity was observed with plasma from male loach. Plasma samples from vitellogenic females and E(2)-treated males were diluted parallel with the purified Vtg standard curve in the ELISA. The detection limit of the assay was 5.7 ng ml(-) (1) and a working range of the standard curve was between 15.6 and 1000 ng ml(-) (1). The intra- and inter-assay coefficients of variations were 6.9% and 10.4%, respectively. The recovery was 104.4%. The assay was applied for measuring vitellogenin concentration in the plasma from 24 wild Chinese loach from Lianyungang, Jiangsu Province, in October 2003. It was found that, in addition to females (plasma Vtg concentration ranging from 518.4 microg ml(-) (1) to 1922.3 microg ml(-) (1)), male loach showed low plasma Vtg--from undetectable (two fish) to 2.9+/-0.7 microg ml(-) (1) (mean+/-S.D.). The results indicate that this method provides a valuable tool for the study of estrogenic effect in Chinese loach.

Animals↗