Low androgen levels induce ferroptosis of rat penile cavernous endothelial cells.

Background: Endothelial dysfunction caused by low androgen levels in penile tissue can lead to erectile dysfunction. The exact mechanism of endothelial dysfunction has not been thoroughly studied. Objective: The study sought to verify whether low androgen levels induce ferroptosis of endothelial cells in rat penile tissue. Methods: Rat penile cavernous endothelial cells (CP-R133) were divided into a no-androgen group (Dihydrotestosterone (DHT): 0 nmol/L), very low-androgen group (DHT: 0.1 nmol/L), low-androgen group (DHT: 1 nmol/L), DHT = 10 nmol/L group, DHT (0 nmol/L) + ferrostatin-1 (Fer-1) group, DHT (0.1 nmol/L) + Fer-1 group, DHT (1 nmol/L) + Fer-1 group, DHT (10 nmol/L) + Fer-1 group. Cell viability, intracellular ferrous ion (Fe2+), malondialdehyde (MDA), GSH into oxidized glutathione (GSSG), reactive oxygen species (ROS), nitric oxide (NO), transferrin receptor 1 protein (TfR1), solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), acyl-CoA synthetase long-chain family member 4 (ACSL4), endothelial nitric oxide synthase (eNOS), and phospho-eNOS (p-eNOS) were detected. Outcomes: Low androgen levels could induce ferroptosis of rat penile cavernous endothelial cells in vivo by upregulating the expressions of TfR1 and ACSL4 and downregulating the expressions of SLC7A11 and GPX4. Results: Cell viability, the levels of glutathione (GSH), NO, SLC7A11, GPX4, and p-eNOS/eNOS in the DHT = 0 nmol/L group were lower than those in the other groups (P < .05). The levels of Fe2+, ROS, MDA, GSSG, TfR1, and ACSL4 in the DHT = 0 nmol/L group were higher than those in the other groups (P < .05). Cell viability and the levels of GSH, NO, SLC7A11, GPX4, and p-eNOS/eNOS in the DHT = 1 nmol/L group were lower than those in the DHT (1 nmol/L) + Fer-1 group, DHT = 10 nmol/L group, and DHT (10 nmol/L) + Fer-1 group (P < .05). The levels of Fe2+, ROS, MDA, GSSG, TfR1, and ACSL4 in the DHT = 1 nmol/L group were higher than those in the DHT (1 nmol/L) + Fer-1 group, DHT = 10 nmol/L group, and DHT (10 nmol/L) + Fer-1 group (P < .05). Clinical Implications: A ferroptosis inhibitor might be a novel drug for treating erectile dysfunction caused by low androgen level. Strengths and Limitations: The results of this study need to be further confirmed in in vitro and in human studies. Meanwhile, further investigation is needed to clarify whether low androgen levels affect ferroptosis of rat penile cavernous smooth muscle and nerve cells. Conclusion: Low androgen levels can induce ferroptosis of endothelial cells in rat penile tissue. Inhibition of ferroptosis can reverse endothelial dysfunction caused by low androgen levels.

[Spatiotemporal Distributions and Ecological Risk Assessments of Typical Antibiotics in Surface Water of Taihu Lake].

Using solid phase extraction-high performance liquid chromatography tandem mass spectrometry, antibiotics belonging to four classes (i.e. sulfonamides, quinolones, tetracycline, and macrolides) in the surface water of Taihu Lake were monitored monthly for a year. Moreover, the potential ecological risks of antibiotics in Taihu Lake were assessed. During the one-year monitoring, all the eighteen target antibiotics were detected to some extent in the surface water. The detection rates of five sulfonamides (sulfamethoxazole, sulfathiazole, sulfadiazine, sulfadimethazine, and trimethoprim) were higher than 50%. The concentrations of quinolones in the surface water were relatively higher. The average and medium concentrations of ciprofloxacin were 13.0 ng·L-1 and 13.5 ng·L-1, respectively. There were significant differences in the antibiotic pollution during the different months, with the average concentrations of the target antibiotics ranging from 7.3 to 33.5 ng·L-1. The concentration levels were lower from June to October, while higher concentrations were observed from February to May and in November. In the surface water of Taihu Lake, the spatial variations of antibiotics among the 20 sampling sites were not significant, with the average concentrations ranging from 13.0 to 14.3 ng·L-1. During the one-year monitoring, the rates of medium and high risks that the antibiotics posed to algae reached 57.5%. The ecological risks of antibiotics were more severe in April and November, and the quinolones may be the dominant risk factor. This issue should be carefully considered by management authorities.

[Temporal and Spatial Occurrence of NSAIDs in Taihu Lake and Relevant Risk Assessment].

Non-steroidal anti-inflammatory drugs (NSAIDs) are a class of drug residues with a high frequency of detection in Taihu Lake. However, little information is available about the occurrence of typical NSAID mixtures in Taihu Lake as a whole across the four seasons. Therefore, for each season, the concentrations of five typical NSAIDs including diclofenac, ibuprofen, indomethacin, naproxen, and ketoprofen were monitored in the water of Taihu Lake by the method of high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) at 19 transects covering the entire lake. The temporal and spatial occurrence of NSAID mixtures in the water of Taihu Lake and their correlation with environmental factors were analyzed, and the mixture risk quotient (MRQ) model was also used to assess the ecological risk of the NSAID mixtures. The research results are as follows:① The concentrations of NSAIDs in the northern, western, and eastern waters of Taihu Lake are at a higher level compared to those in the central waters. Ketoprofen is the main contributor to the contamination of NSAID mixtures in all regions of Taihu Lake. ② The concentrations of NSAIDs in Taihu Lake are higher in summer (15.9-134.3 ng·L-1) and autumn (16.4-144.6 ng·L-1) but lower in spring (25.3-72.5 ng·L-1) and winter (14.6-57.4 ng·L-1), being significantly correlated with water conductivity and pH, respectively. ③ The MRQ model evaluation reveals that there are nine sections in Taihu Lake showing a high ecological risk (MRQ>1) from NSAID mixtures throughout the year. The ecological risk of the NSAID mixtures at a medium or high level (MRQ>0.1) lasts for a long time spanning the spring, summer, and autumn seasons, of which the risk is greatest in autumn. Overall, the pollution caused by the NSAID mixtures in the water of Taihu Lake should not be ignored, and especially great attention should be paid to the pollution in autumn.

[Chemical constituents of bark of Taxus chinensis var. mairei].

OBJECTIVE: To study the chemical constituents in the bark of Taxus chinensis var. mairei collected from southeast of China. METHODS: Chemical constituents were isolated and purified by column chromatography, Prep-TLC, and preparative HPLC. The structures were identified on the basis of 1D-and 2D-NMR spectral analysis. RESULTS: Twelve taxane diterpenoids were isolated from the bark of Taxus chinensis var. mairei grown in southeast of China. They were identified as: taxagifine (1), decinnamoyltaxagifine (2), 19-debenzoyl-19-acetyltaxinine M(3), 9-dihydro-13-acetyl-baccatin III (4), 7, 9-dideacetylbaccatin IV (5), 1,3-dihydro-taxinine (6), taxumairol C (7), taxezopidine J (8), 7-xylosyl-10-deacetyl-taxol A (9),10-deacetyltaxol (10), taxicin II (11), and 2alpha, 7beta, 10beta-triacetoxy-5alpha, 13alpha-dihydroxy-2 (3 --> 20) abeotaxa-4 (20), 11-dien-9-one (12). CONCLUSION: Compounds 1, 2, 4 - 6, 8, 9, 11 and 12 are obtained from this plant for the first time. Compound 7 is obtained from the bark of Taxus chinensis var. mairei for the first time.

[Effect of phosphorus on the production of microcystin].

Effect of phosphorus on the production of microcystin was researched. The effects of soluble reactive phosphorus (SRP) on the growth of cells and on the production of Microcystin were studied. In addition, the efficiency of four different phosphorus compounds was researched. The results showed that microcystin increased with the increase of SRP, and c(TP) = 0.55 mg x L(-1) was the best growth concentration. When c(TP) < or = 0.55 mg x L(-1), the microcystin production increased with the increase of phosphorus concentration and was the lowest without phosphorus. Moreover, when c(TP) > 0.55 mg x L(-1), the microcystin was restrained by the content of phosphorus. At the same time, the effects of three inorganic substance of different phosphorus forms (K3PO4, K2HPO4, and KH2PO4) were no significant difference, but their effects on the production of microcystis were larger than organic phosphorus of sodium beta-glycerophosphate (GP).

[Study on elasticity of medical service demand at the township level in China].

OBJECTIVE: To find out the economic laws regulating medical service demand in accordance with influencing factors at the township level, thus to provide references for further adjusting the medical service demand reasonably in the future. METHODS: The model of medical service demand was established to measure the elasticity of demand in 49 township health clinics in 1995, 1999, 2003 and 2007. RESULTS: The price elasticity of outpatient and inpatient demand was stable during the four periods, and the average value was -0.029 and -0.132 respectively; the average value of income elasticity was 0.973 and 0.977, registering a downward trend in general. CONCLUSION: The medical service demand at the township level is price inelastic, indicating that it is a necessity for rural residents. The downward trend of income elasticity under the influence of some health policies illustrates a lightening in economic burden for medical service demand among rural residents in township health clinics.

[Property of adsorption about ammonium on suspended mineral matters in eutrophic water].

Static experiments were performed to investigate the adsorption characteristics of ammonium by suspended mineral matters (SPM). Three kinds of suspended mineral matters including montmorillonite, kaolin and the particles separated from the sediments of the Taihu Lake were used as the sorbent. The experiments show that the equation could be gotten within 30 min, and that the ammonium adsorption on mineral particles conformed to Herry isotherm. The parting coefficient of the adsorption about ammonium could reach 548.30, 287.36, 191.27 L/kg in experimental condition that there were 1 000 mg/L mineral particles and 1.0 mg/L ammonium in water with pH 7.00. Some effectors such as temperature, pH and salinity of the water on the adsorption about ammonium were observed. The results show that the quantity of adsorbed ammonium slightly decrease with the increasing of temperature and salinity, and greatly do with increasing of pH. The quantity decrease rapidly also with the increasing of the content of mineral particles below 1 000 mg/L.

Degradation of microcystins in aqueous solution with in situ electrogenerated active chlorine.

A new and efficient method for the degradation of microcystins (one family of blue algal toxins) was developed and studied. Microcystins (MCs) in water were directly and effectively removed by active chlorine transformed in situ from the naturally existing Cl- in water resource using electrochemical method. Titanium coated with RuO2 and TiO2 was used as the anode. Microcystin-RR (MCRR) and Microcystin-LR (MCLR) were chosen as the model compounds of MCs. The results suggested that 20.87 mgl(-1) MCs (12.58 mgl(-1) MCRR and 8.29 mgl(-1) MCLR) in aqueous solution with 1.85 mM Cl- could be synchronously decomposed within 15 min electrolysis under the condition of the current density 8.89 mAcm(-2), 20 degrees C and pH 7.00. The qualitative analysis showed that the heptapetide ring and the Adda group of both treated MCs were changed. The results also indicated that the removal rates of both MCs increased with the increasing of chloride concentration and applied current density, but decreased with the increasing of initial concentration of MCs and initial pH of electrolyte. In the absence of Cl-, only a small fraction of both MCs were decomposed by direct anodic oxidation, while their almost complete removals could be obtained in the case of indirect electrooxidation with in situ electrogenerated active chlorine from Cl- in water.

[Analysis of microcystins by LC-ESI/MS in the algal cells collected from Guanting Reservoir].

Microcystins in the algal cells collected from the water bloom of the Guanting Reservoir were further investigated by LC-ESI/MS after they were studied by the method of HPLC. The results show that three of five microcystins contained in the algal cells of the blooms are frequent Microcystin-RR, Microcystin-LR and Microcystin-YR, whose molecular weights are 1038, 995 and 1045 respectively. The molecular weights of the other two microcystins are 1052 and 1009, which are corresponding to the molecular weights of Microcystin-YY and Mglu-LR respectively, however the complete identification of both MCs have to be carried out further.