Roles of photochemical consumption of VOCs on regional background O3 concentration and atmospheric reactivity over the pearl river estuary, Southern China.

Understanding of the photochemical ozone (O3) pollution over the Pearl River Estuary (PRE) of southern China remains limited. We performed an in-depth analysis of volatile organic compounds (VOCs) data collected on an island (i.e., the Da Wan Shan Island, DWS) located at the downwind of Pearl River Delta (PRD) from 26 November to 15 December 2021. Abundances of O3 and its precursors were measured when the air masses originated from the inland PRD. We observed that the VOCs levels at the DWS site were lower, while the mixing ratio of O3 was higher, compared to those reported at inland PRD, indicating the occurrence of photochemical consumption of VOCs during the air masses transport, which was further confirmed by the composition and diurnal variations of VOCs, as well as ratios of specific VOCs. The simulation results from a photochemical box model showed that the O3 level in the outflow air masses of inland PRD (O3(out-flow)) was the dominant factor leading to the intensification of O3 pollution and the enhancement of atmospheric radical concentrations (ARC) over PRE, which was mainly contributed by the O3 production via photochemical consumption of VOCs during air masses transport. Overall, our findings provided direct quantitative evidence for the roles of outflow O3 and its precursors from inland PRD on O3 abundance and ARC over the PRE area, highlighting that alleviation of O3 pollution over PRE should focus on the impact of photochemical loss of VOCs in the outflow air masses from inland PRD.

Combined effects of binary mixtures of 17ß-estradiol and testosterone in western mosquitofish (Gambusia affinis) after full life-cycle exposure.

Estrogens and androgens are typical steroid hormones and often occur together in contaminated aquatic environments, but their mixed effects in aquatic organisms have been less well reported. In this study, the endocrine disrupting effects of binary mixtures of 17ß-estradiol (E2) and testosterone (T) in western mosquitofish (Gambusia affinis) were assessed by analyzing the sex ratio, secondary sex characteristics, gonadal histology, and transcriptional expression of target genes related to the hypothalamic-pituitary-gonadal (HPG) axis in G. affinis (from embryos) continuously exposed to E2 (50 ng/L), T (T1: 50 ng/L; T2: 200 ng/L), and mixtures of both (E2 + T1: 50 + 50 ng/L; E2 + T2: 50 + 200 ng/L) for 119 d. The results showed that exposure to E2 + T1 and E2 + T2 reduced the length ratio of ray 4/6 ratio in male G. affinis, suggesting feminized phenomenon in male G. affinis. Furthermore, 16.7-38.5 % of female G. affinis showed masculinized anal fins and hemal spines when exposed to T alone and in combination with E2. Importantly, the transcriptional levels of certain target genes related to the HPG axis were significantly altered in G. affinis following exposure to E2 and T alone and in combinations. Moreover, exposure to E2 and T in combinations can lead to combined effects (such as synergistic and antagonistic effects) on the transcriptional levels of some genes. These results collectively suggest that exposure to environmentally relevant concentrations of E2 and T alone and in mixtures can impact the endocrine system of G. affinis, and may pose potential risks in aquatic systems.

Interaction of 17α-ethinylestradiol and methyltestosterone in western mosquitofish (Gambusia affinis) across two generations.

The interactions between estrogen and androgen in aquatic animals remain largely unknown. In this study, two generations (F0 and F1) of western mosquitofish (Gambusia affinis) were continuously exposed to 17α-ethinylestradiol (EE2, 10 ng/L), methyltestosterone (MT, 10 ng/L (MTL); 50 ng/L (MTH)), and mixtures (EE2+MTL and EE2+MTH). Various endpoints, including sex ratio (phenotypic and genetic), secondary sex characteristics, gonadal histology, and transcriptional profile of genes, were examined. The results showed that G. affinis exposed to MTH and EE2+MTH had a > 89.7 % of phenotypic males in F1 generation, with 34.5 and 50.0 % of these males originated from genetic females, respectively. Moreover, females from F0 and F1 generations exposed to MTH and EE2+MTH exhibited masculinized anal fins and skeletons. The combined effect of MT and EE2 on most endpoints was dependent on MT. Furthermore, significant transcriptional alterations in certain target genes were observed in both the F0 and F1 generations by EE2 and MT alone and by mixtures, showing some degree of interactions. These findings that the effects of EE2+MTH were primarily on the phenotypic sex of G. affinis in offspring generation suggest that G. affinis under chronic exposure to the binary mixture contaminated water could have sex-biased populations.

Exposure to estrone disrupts the endocrine system of western mosquitofish (Gambusia affinis).

Estrone (E1) is one of the predominant natural estrogens detected in aquatic environments, yet little is known about its effects on the endocrine system in fish. In this study, the sex ratio, secondary sexual characteristics, gonadal histology, and transcriptional levels of genes closely related to sex differentiation and hypothalamic-pituitary-gonadal-liver (HPGL) axis were assessed in western mosquitofish (Gambusia affinis) after a full life-cycle exposure to E1 (0, 25.4, 143, 740, and 4300 ng/L) for 119 days. The results showed that exposure to 4300 ng/L of E1 resulted in 100% female and inhibited the growth of females. Exposure to environmentally relevant concentrations of E1 (143 and 740 ng/L) led to obvious feminization of skeletons and anal fins in males. Exposure to 740 and 4300 ng/L of E1 increased the proportion of mature spermatocytes in females, and exposure to 143 and 740 ng/L decreased the proportion of mature spermatocytes in males. Moreover, the transcripts of genes related to sex differentiation and HPGL axis were changed in the E1-exposed adult fish and embryos inside females. This study has provided valuable data on the endocrine disruption effects of E1 at environmentally relevant concentrations in G. affinis.

Transgenerational effects of androstadienedione and androstenedione at environmentally relevant concentrations in zebrafish (Danio rerio).

Androgens androstadienedione (ADD) and androstenedione (AED) are predominant steroid hormones in surface water, and can disrupt the endocrine system in fish. However, little is known about the transgenerational effects of ADD and AED in fish. In the present study, F0 generation was exposed to ADD and AED from 21 to 144 days post-fertilization (dpf) at nominal concentrations of 5 (L), 50 (M) and 500 (H) ng L-1, and F1 generation was domesticated in clear water for 144 dpf. The sex ratio, histology and transcription in F0 and F1 generations were examined. In the F0 generation, ADD and AED tended to be estrogenic in zebrafish, resulting in female biased zebrafish populations. In the F1 generation, ADD at the H level caused 63.5% females, while AED at the H level resulted in 78.7% males. In brain, ADD and AED had similar effects on circadian rhythm in the F0 and F1 generations. In the F1 eleutheroembryos, transcriptomic analysis indicated that neuromast hair cell related biological processes (BPs) were overlapped in the ADD and AED groups. Taken together, ADD and AED at environmentally relevant concentrations had transgenerational effects on sex differentiation and transcription in zebrafish.

Chemical characteristics and toxicological effects of leachates from plastics under simulated seawater and fish digest.

In recent years, the ecological risks of plastics to marine environments and organisms have attracted increasing attention, especially the leachates from plastics. However, a comprehensive knowledge about the leaching characteristics and subsequent toxicological effects of leachates is still sparse. In this study, 15 different plastic products were immersed in simulated seawater and fish digest for 16 h. The leachates were analyzed through non-target and target analyses and their toxicological signatures were assessed by bioassays. In total, 240 additives were identified from the plastic leachates, among which plasticizers represented the most (16.7%), followed by antioxidants (8.7%) and flame retardants (7.1%). Approximately 40% of plastic leachates exhibited significant inhibitory effects on the bioluminescence using a recombinant luminescent assay. In addition, both the hyperactive and hypoactive behaviors were displayed in the larvae of marine medaka (Oryzias melastigma) exposed to some plastic leachates. In general, the number and amount of identified compounds under simulated fish digest were less than those under simulated seawater. However, the simulated fish digest leachates triggered higher toxicity. Redundancy analysis demonstrated that identified additives did not adequately explain the toxicological effects. Future research should focus on the identification of more additives in the plastic leachates and their potential ecological risks.

Levonorgestrel and dydrogesterone affect sex determination via different pathways in zebrafish.

Levonorgestrel (LNG) and dydrogesterone (DDG) are two commonly used synthetic progestins that have been detected in aquatic environments. They could affect fish sex differentiation, but the underlying mechanisms remain unknown. Here we investigated the effects of LNG (5 ng L-1 and 50 ng L-1), DDG (100 ng L-1) and their mixtures on gonadal differentiation and sex determination in zebrafish at transcriptomic and histological levels from 2 hours post-fertilization (eleutheroembryos) to 144 days post-fertilization (sexual maturity). Germ cell development and oogenesis pathways were significantly enriched in LNG and the mixture of LNG and DDG treatments, while insulin and apoptosis pathways in the DDG treatment. LNG and the mixture of LNG and DDG strongly decreased transcripts of germ cell development and oogenesis related genes, while DDG increased the transcripts of insulin and apoptosis related genes at 28 days post fertilization (dpf) and 35 dpf. Furthermore, DDG caused ∼ 90% males, and LNG and the mixture of LNG and DDG resulted in 100% males on all sampling dates. Specifically, most males in LNG and the mixture of LNG and DDG treatments were "Type I" males without juvenile oocytes at 28 dpf and 35 dpf, while those in DDG treatment were "Type II" and "Type III" males with a few juvenile oocytes. These results indicated that LNG and DDG promoted testicular differentiation via different pathways to cause male bias. LNG and DDG mixtures have similar effect on testicular differentiation to LNG alone. The findings from this study could have significant ecological implications to fish populations.

Endocrine disrupting effects of binary mixtures of 17ß-estradiol and testosterone in adult female western mosquitofish (Gambusia affinis).

Androgens and estrogens often co-exist in aquatic environments and pose potential risks to fish populations. However, little is known about the endocrine disrupting effects of the mixture of androgens and estrogens in fish. In this study, transcriptional level of target genes related to the hypothalamic-pituitary-gonadal-liver (HPGL) axis, sex hormone level, VTG protein concentration, histology and secondary sex characteristic were assessed in the ovaries and livers of adult female western mosquitofish (Gambusia affinis) exposed to 17ß-estradiol (E2), testosterone (T), and mixtures of E2 and T for 91 days. The results showed that the transcriptional expression of cytochrome P450, family 19, subfamily A, polypeptide 1a (Cyp19a1a) was suppressed in the 200 ng/L T treatment and the 50 ng/L E2 + 200 ng/L T treatment in the ovaries. Steroidogenic acute regulatory protein (Star) and Cyp11a1 showed a similar expression pattern in the T treatment to its corresponding T + E2 mixtures. In the ovaries, the concentrations of 17ß-estradiol and testosterone were decreased in most treatments compared with the solvent control. VTG protein was induced in all steroid treatment. However, exposure to T or E2 + T mixture did not cause the abnormal cells of the ovaries and livers and an extension of the anal fins in female G. affinis. This study demonstrates that chronic exposure to E2, T and their mixtures affects the transcripts of genes in the HPGL axis, steroid hormone level and VTG protein concentration in the ovaries and livers, but fails to cause the histopathological effect of the ovaries and livers and alter the morphology of the anal fins in G. affinis.

Simultaneous removal of Pb2+, Cu2+ and Cd2+ ions from wastewater using hierarchical porous polyacrylic acid grafted with lignin.

In PAA-g-lignin, phase separation, caused by the difference in expansion properties between lignin and polyacrylic acid, is used to build a porous hydrogel. In this study, PAA-g-APL was produced by grafting polyacrylic acid with acid-pretreated alkali lignin. Acid-pretreated alkali lignin acts as a hierarchical pore-forming agent that enhances the simultaneous adsorption capacities for Pb2+, Cu2+ and Cd2+ ions from wastewater. Notably, PAA-g-APL acted as a selective adsorbent for Pb2+ ions has an excellent selective removal coefficient α (20.22) in contaminated wastewater contained Cu2+ ions. Its molar partition coefficient for Pb2+ ions (68 %) is higher than that for either Cu2+ ions (28.6 %) or Cd2+ ions (3.4 %). At equilibrium, the total adsorption capacities of PAA-g-APL for Pb2+, Cu2+ and Cd2+ were 1.076 mmol g-1, 0.3233 mmol g-1 and 0.059 mmol g-1, respectively. The experimental kinetic data fitted well to a pseudo-second order model and to an intra-particle-diffusion model. The Freundlich isotherm model gave the best fit with the experimental equilibrium data. The ΔG° for PAA-g-APL is < 0, indicating that the adsorption of heavy metal ions is a spontaneous process. This study provides a highly promising candidate for the treatment of wastewater contaminated with a mixture of heavy metals.

Endocrine disruption in western mosquitofish from open and closed aquatic ecosystems polluted by swine farm wastewaters.

Swine farm wastewaters (SFWs) are generally discharged either directly into nearby rivers or into fish ponds as a source of fertilizer/food for aquaculture in China. SFWs contain various contaminants including steroid hormones. However, there is an extreme paucity of data on their effects in fish populations. Here we investigated the endocrine disrupting effects of SFWs in G. affinis from 2 rivers (7 sites) and 2 fish ponds (2 sites) receiving SFWs and a reference site in Guangdong Province, China. In this study, a total number of 3078 adult western mosquitofish (Gambusia affinis) were collected and the sex ratio was determined. In addition, secondary sexual characteristics were examined and the transcriptional levels of target genes were analyzed. The results showed the mosquitofish populations had a significant increase in male-to-female ratio from 7 sites (including 2 fish ponds) among the 9 sampling sites. The hemal spines of females were masculinized at most sites while the hemal spines of males were feminized at approximately half of the sites (including 2 fish ponds). Significant reduction in vitellogenin (Vtg) mRNA expression was observed in females from 2 sites (including RS7) while elevated Vtg mRNA expression was noticed in males from 2 sites along the rivers (including RS7). Redundancy analysis showed that androgens in the water samples were closely related with male-to-female ratio in the mosquitofish populations and the masculinized hemal spines of females. The findings from this study demonstrated that discharge of SFWs could result in occurrence of both masculinized females and feminized males in mosquitofish population.

A composite carbon-based solid acid-supported palladium catalyst (Pd/C-SO3H) for hydrogenolysis of plant-derived polymeric proanthocyanidins.

A composite catalyst, Pd/C-SO3H, has been prepared to depolymerize plant-derived polymeric proanthocyanidins (PPC). Different reaction conditions were explored and the catalyst was shown to have good performance and recyclability, as well as good thermal and acid-base stability. UV, FTIR and 1H NMR analyses showed that the depolymerization products (oligomeric proanthocyanidins, OPC) retained a condensed flavanol polyphenol structure and that the basic structural units of the polymers had not been destroyed. The antioxidant activity of the OPC was better than that of the PPC, and also better than that of 2,6-di-tert-butyl-4-methylphenol, which is widely used in industry, including as a food additive. OPC could, therefore, be developed as a commercially useful radical chain-breaking antioxidant. The preparation of Pd/C-SO3H provides an example of the design and development of a new composite catalyst that has high practical value. The study also provides a new technical route for the depolymerization of PPC and thus makes a useful contribution to the high-value utilization of renewable plant resources.

H3PW12O40/ZrO2 and 1-Butyl-3-methylimidazolium Chloride: A Double-Effect Catalyst for the Degradation of Alkali Lignin.

Alkali lignin is a component of the waste black liquor produced by the paper-making industry that is difficult to degrade. In recent years, the biological activities of lignin, such as free-radical scavenging and antioxidant capacity, have received increasing attention. Here, we prepared H3PW12O40/ZrO2 and used this catalyst together with the ionic liquid 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) as a double-effect catalyst for the degradation of alkali lignin. Single-factor and orthogonal tests showed that the best degradation conditions were as follows: reaction time, 2 h; reaction temperature, 100 °C; mass ratio of H3PW12O40/ZrO2 to lignin, 1:4; and substrate concentration, 2.5%. The phenolic hydroxyl group content of the lignin degradation product increased by 231.2% and the total hydroxyl group content increased by 337.1% when the double-effect catalyst was used rather than [BMIM]Cl alone. Analysis by gel permeation chromatography showed that both the weight-average molecular weight and the number-average molecular weight of the product were reduced and that the lignin was degraded into small-molecular-weight compounds by the macromolecule. The product after the catalytic degradation of lignin showed a markedly increased antioxidant capacity, which was similar to that of the commercial antioxidant, 2,6-ditert-butyl-4-methylphenol. The study opens up a new direction for the better utilization of lignin.

Low-Cost Ru/C-Catalyzed Depolymerization of the Polymeric Proanthocyanidin-Rich Fraction from Bark To Produce Oligomeric Proanthocyanidins with Antioxidant Activity.

A new method has been developed for the high-value utilization of larch bark, which is regarded as a low-value byproduct of the logging industry. Polymeric proanthocyanidins (PPCs) were extracted from the Larix gmelinii bark and depolymerized by catalytic hydrogenolysis, using ruthenium/carbon (Ru/C) as the catalyst. The method has been found that although the molecular weight of the depolymerized product was significantly lower, the basic structural units were not destroyed, and the product retained a condensed flavanol polyphenol structure; the depolymerized product contains very little Ru metal and thus complies with food safety standards; the antioxidant properties of both the depolymerized products and PPCs were better than those of the commonly used antioxidant 2,6-di-tert-butyl-4-methylphenol. The relative molecular weight and steric hindrance of the depolymerized products were lower than those of the PPCs, leading to better antioxidant performance. A new technical route for the depolymerization of PPCs from the L. gmelinii bark is provided. The route offers practical and commercial advantages, and the product could have many applications as an antioxidant.

The Effect of Degradation of Soda Lignin Using Pd/SO42-/ZrO2 as a Catalyst: Improved Reactivity and Antioxidant Activity.

To the value-added application of the soda lignin by improving its reactivity and antioxidant activity, a self-made Pd/SO42-/ZrO2 catalyst was used to catalyze the degradation reaction of soda lignin. The catalyst was loaded with the palladium of 1.47 wt.% while retaining the super acidity of SO42-/ZrO2. The reaction condition was determined as follows: the dioxane-water solution was selected as the reaction solution, the addition amount of the catalyst was 5 wt.% of the soda lignin, the system was heated at 100 °C for 4 h under a hydrogen pressure of 3 MPa. The reactivity of the catalyzed-soda lignin compared to the soda lignin before the reaction was significantly improved: the values of phenolic hydroxyl groups and total hydroxyl groups were increased by 35.3% and 97.1%, respectively, and the value of methoxy groups was decreased by 13%. Approximately 63.3% of the ß-O-4 bonds were cleaved, which resulted in a reduction of the weight average molecular weight from 8200 g·mol-1 to 4900 g·mol-1. At the same time, the EC50 values of the catalyzed-soda lignin on DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS+ (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radicals scavenging were decreased by 20.6% and 32.6%, respectively, and the reducing power of catalyzed-soda lignin at the absorption value of 0.5 was increased by 10.5%. The Pd/SO42-/ZrO2 catalyst works by breaking the ß-O-4 linkages and degrading the methoxy groups. The catalyzed-soda lignin exhibits the possibility of being used as the antioxidants, grafting precursors, adhesive additives, and raw materials for lignin/polymer composites.

Use of autologous platelet rich fibrin-based bioactive membrane in pressure ulcer healing in rats.

OBJECTIVE: To verify the feasibility of treating pressure ulcers (PUs) with autologous platelet-rich fibrin-based (PRF) bioactive membrane, both in vitro and in vivo. METHOD: An animal model using adult male Sprague-Dawley rats was used. Pressure was periodically exerted on the skin to induce localised ischaemia by using an external magnet and transplanted metal disc. After a PU developed, the rats were divided into two groups: a treatment group and a control group. Rats in the treatment group were then treated with PRF bioactive membrane every three days. RESULTS: A total of 20 rats were used in this study. At days three and seven, the PU area in the PRF bioactive membrane-treated group was significantly smaller than that in the control group, and after 14 days of treatment, the PUs in the PRF bioactive membrane treatment group had healed. Haemotoxylin and eosin staining, immunohistochemistry and Western blot results indicated that PRF bioactive membrane induced wound healing by increasing the thickness of the regenerated epidermis and by upregulating vascular endothelial growth factor expression. Further, we found that different concentrations of rat autologous PRF soluble factors extraction components could significantly promote rat aortic endothelial cell proliferation, wound healing and migration ability in vitro. CONCLUSION: Overall, results indicate that PRF bioactive membrane promotes PU healing in rats. Thus, it may represent a natural and effective wound-healing tool for use in the treatment of clinical skin PUs in humans in the future.

Changes in heavy metal mobility and availability in contaminated wet-land soil remediated using lignin-based poly(acrylic acid).

To mitigate the serious ecological problems and risks to human health that are posed by heavy metals in the soil, it is important to enhance the efficiency of heavy metal extraction by washing contaminated soil using chemical methods. Secondary pollution of soil by chemical chelating agents has, however, brought a new threat to the environment. Here, we describe a biodegradable LBPAA (lignin based poly(acrylic acid)) composite that was designed as a chelating agent to wash soil contaminated with Cu2+, Zn2+, Cd2+ and Pb2+ ions. Extraction and ion transfer of heavy metal ions by the LBPAA composite improved the remediation rate of contaminated soil during water leaching. After washing five times, the LBPAA-assisted elution process reduced the amount of Cu2+, Zn2+, Cd2+ and Pb2+ ions in contaminated soil to 22.57%, 52.60%, 13.63% and 17.95%, respectively. These values are 2.39-fold, 5.04-fold, 5.04-fold and 1.31-fold, respectively, better than elution with deionized water. Additionally, LBPAA is able to sequester Cd2+ and Pb2+ ions from the contaminated soil and transfer them to the eluent. In summary, this work provides a safe, environmentally friendly and sustainable remediation strategy for heavy metal-contaminated soil and demonstrates a new application for lignin in the field of soil remediation.

Correlation between Solubility Parameters and Properties of Alkali Lignin/PVA Composites.

Although lignin blending with thermoplastic polymers has been widely studied, the usefulness of the lignin⁻polymer composites is limited by the poor compatibility of the two components. In the present study, alkali lignin/PVA composite membranes were prepared by incorporating 10%, 15%, 20% and 25% alkali lignin into the composites. The thermodynamic parameters of the composites were measured using inverse gas chromatography (IGC). Composite membranes with 10%, 15%, 20%, and 25% alkali lignin had solubility parameters of 17.51, 18.70, 16.64 and 16.38 (J/cm³)0.5, respectively, indicating that the solubility parameter firstly increased, and then decreased, with increasing proportions of alkali lignin. When the alkali lignin content was 15%, the composites had the largest solubility parameters. The composite membrane with an alkali lignin content of 15% had a tensile strength of 18.86 MPa and a hydrophilic contact angle of 89°. We have shown that the solubility parameters of blends were related to mechanical and hydrophilic properties of the composites and the relationships have been verified experimentally and theoretically.

Quantitative Analysis of Relationship between Hansen Solubility Parameters and Properties of Alkali Lignin/Acrylonitrile-Butadiene-Styrene Blends.

Blends of alkali lignin and acrylonitrile-butadiene-styrene (ABS) resin are physically mixed and injected into the injection molding system. Although the components of the blend are bound together by intermolecular forces, noticeable phase separation still occurs. In the present study, inverse gas chromatography technology was used to characterize the Hansen solubility parameters of alkali lignin/ABS blends. The relationship between the Hansen solubility parameters and thermodynamic properties was then determined. Hansen solubility parameters, at room temperature, of alkali lignin/ABS blends containing 0, 10, 20, and 30 wt % alkali lignin were 17.40, 19.20, 18.98, and 17.37 (J/cm3)0.5, respectively. Hansen solubility parameters of the blends were shown, both experimentally and theoretically, to be related to their mechanical and thermal properties.

Naringin protects against steroid­induced avascular necrosis of the femoral head through upregulation of PPARγ and activation of the Notch signaling pathway.

Naringin, a flavonoid, is the effective pharmaceutical ingredient of drynaria, with the effects of healing fractures, strengthening bones and promoting kidney function. The aim of the present study was to investigate the potential effect of naringin on steroid­induced avascular necrosis of the femoral head (SANFH). Treatment with naringin markedly protected against the steroid­induced decrease in serum osteocalcin levels, and the rate of osteonecrosis in a model of SANFH. In addition, naringin decreased the total cholesterol and low density lipoprotein/high density lipoprotein ratio in the SANFH rabbit. It was observed that naringin markedly inhibited caspase­3 activity, increased runt­related transcription factor 2 and transcription factor sp7 mRNA expression, promoted alkaline phosphatase activity and upregulated collagen I, peroxisome proliferator­activated receptor (PPAR) Î³2, neurogenic locus notch homolog protein (Notch), ß­catenin and phosphorylated­Rac­α serine/threonine protein kinase protein expression in the SANFH rabbit. The results of the present study demonstrated that naringin protects against SANFH through upregulation of PPARγ2 and activation of the Notch signaling pathway, and may be a useful addition to the treatment options for diseases of the femoral head.

Masculinization and reproductive effects in western mosquitofish (Gambusia affinis) after long-term exposure to androstenedione.

Androstenedione (AED) is a naturally occurring steroid hormone. It is metabolized to potent androgens, which may induce androgenic effects in fish. However, little is known whether and how the androgens interfere with the fish gonadal development and reproduction. This study aimed at demonstrating the effects of long-term AED exposure on reproduction and development in mosquitofish (Gambusia affinis). The growth, development and several morphological endpoints, including the segment number and length of anal fin, histological changes of gonads and liver, were evaluated in mosquitofish during development from fertilized embryo to adulthood (180 days) after exposure of AED at environmentally relevant concentrations. We found that the growth (length, body weight and condition factor) of fish was negatively correlated with AED concentration in females, but not in males. The significant elongation of the ray and increment of segment numbers in the anal fin, were detected in all mosquitofish after exposure. Moreover, AED exposure (0.4gµ/L) caused damages in gonads and reduced the number of pregnant females. These findings indicate that AED has adverse effects on the growth and development of the western mosquitofish after long-term exposure (180d). Long-term exposure (180d) to AED, including environmentally relevant concentration (0.4µg/L and 4µg/L), induced masculinization in female mosquitofish under the experimental conditions.