Acid-induced tubular g-C3N4 for the selective generation of singlet oxygen by energy transfer: Implications for the photocatalytic degradation of parabens in real water environments.

Parabens are widely present in aquatic environments and pose potential health risk. Although great progress has been made in the field of the photocatalytic degradation of parabens, the powerful Coulomb interactions between electrons and holes are the major limitations to photocatalytic performance. Hence, acid-induced tubular g-C3N4 (AcTCN) was prepared and applied for the removal of parabens from a real water environment. AcTCN not only increased the specific surface area and light absorption capacity, but also selectively generated 1O2 via an energy transfer-mediated oxygen activation pathway. The 1O2 yield of AcTCN was 11.8 times higher than that of g-C3N4. AcTCN exhibited remarkable removal efficiencies for parabens depending on the length of the alkyl group. Furthermore, the rate constants (k values) of parabens in ultrapure water were higher than those in tap and river water because of the presence of organic and inorganic species in real water environments. Two possible pathways for the photocatalytic degradation of parabens are proposed based on the identification of intermediates and theoretical calculations. In summary, this study offers theoretical support for the efficient enhancement of the photocatalytic performance of g-C3N4 for the removal of parabens in real water environments.

Solar-induced efficient propylparaben photodegradation by nitrogen vacancy engineered reticulate g-C3N4: Morphology, activity and mechanism.

Propylparaben (PrP) has attracted extensive concerns due to its wide occurrence in wastewater and potential health risk. Herein, nitrogen vacancy engineered reticulate g-C3N4 (Nv-RCN) was successfully synthesized for the photodegradation of PrP. Nv-RCN exhibited larger specific surface area, greater light absorption ability, higher transfer and separation efficiency of charge carriers in comparison with bulk g-C3N4 (CN). According to the characterization results and DFT calculation, nitrogen vacancy could capture electrons and facilitate oxygen adsorption. The Nv-RCN exhibited an outstanding PrP removal efficiency of 94.3 %, and the corresponding apparent rate constant of Nv-RCN was 3.37 times higher than that of CN. High O2 concentration (8 mg/L) and low pH value (pH = 3) promoted PrP photodegradation based on Box-Behnken Design. The O2- was the major radical during PCOP of Nv-RCN, and could oxidize PrP by decarbonylation and dealkylation. This study provided new insights to the improvement of photodegradation performance of g-C3N4 for parabens removal and related environmental remediation.

Activation of peroxisome proliferator-activated receptor γ (PPARγ) through NF-κB/Brg1 and TGF-ß1 pathways attenuates cardiac remodeling in pressure-overloaded rat hearts.

BACKGROUND/AIMS: Cardiac remodeling is a common pathophysiological change along with chronic hypertension and myocardial infarction. Recent evidence indicated that cardiac tissue expressed peroxisome proliferator-activated receptor γ (PPARγ). However, the functional role of PPARγ in cardiac remodeling remained unclear. The present study was designed to investigate the relationship between PPARγ activation and pressure overload-induced cardiac remodeling. METHODS: Cardiac remodeling model was successfully established by abdominal aorta ligation. Cardiac fibrosis and cardiomyocyte hypertrophy were simulated by 100 nM angiotensin II (Ang II) in vitro. Haemodynamic parameters, the expressions of Brg1, α-MHC, ß-MHC, transforming growth factor beta 1 (TGF-ß1), collagen-I, collagen-III and NF-κB were examined. RESULTS: Morphological and haemodynamic measurements showed that the activation of PPARγ improved the impaired cardiac function and decreased interstitial fibrosis in cardiac remodeling rats. Further results also showed that the activation of PPARγ inhibited the expressions of Brg1 and TGF-ß1 in the cardiac remodeling hearts. The activation of PPARγ also inhibited the proliferation and collagen production of cardiac fibroblasts, and down-regulated the activity of Brg1 and the expression of TGF-ß1 induced by Ang II in cultured neonatal rat cardiomyocytes and cardiac fibroblasts, respectively, through NF-κB pathway. CONCLUSIONS: These results suggested that PPARγ activation effectively inhibited cardiac remodeling processes by suppression of Brg1 and TGF-ß1 expressions through NF-κB pathway in the pressure-overloaded hearts induced by abdominal aorta ligation in rats.

[A random control study of indomethacin-containing MYCu intrauterine contraceptive device for 60 months].

OBJECTIVE: To explore the clinical efficacy and safety of MYCu intrauterine contraceptive device (IUD) containing indomethacin. METHODS: From October 1 to December 31, 2004, women of child-bearing age requiring IUD for contraception were chosen from the Outpatient Departments of China-Japan Friendship Hospital of Jilin University, Peking University First Hospital, Peking University Third Hospital, Jilin University Second Hospital and Affiliated Shengjing Hospital of China Medical University. They were randomly inserted with MYCuIUD and control TCu380A IUD each for 1000 cases and followed up at 1, 3, 6, 12, 24, 36, 48 and 60 months post-insertion. RESULTS: When MYCu IUD group and TCu380A group 60 months post-insertion were compared, the cumulative pregnancy rates with IUD in situ were 2.38/100 women per year and 2.84/100 women per year respectively. And the difference had no statistical significance (P > 0.05); the cumulative expulsion rates, mostly of partial expulsion and downward movement, were 0.87/100 women per year and 2.94/100 women per year respectively. And the difference had statistical significance (P < 0.05); the cumulative termination rates due to bleeding/pain were 3.57/100 women per year and 4.83/100 women per year respectively. And the difference had no statistical significance (P > 0.05); Side effects in MYCu group were less pronounced than those in TCu group. And the inter-group differences had statistical significance (P < 0.05). CONCLUSION: As a comparatively ideal medicated medical device, MYCu IUD has an excellent contraceptive efficacy, a low rate of expulsion and side effects and good reversibility. Particularly a low occurrence rate of bleeding and pain during early insertion is recommended. Its life expectancy is 15 years. And its contraceptive effectiveness and safety after 5 years should be examined during further follow-ups.

Effect of dopamine and metaraminol on the renal function of patients with septic shock.

BACKGROUND: Vasoactive drugs are often necessary for reversing hypotension in patients with severe infection. The standard for evaluating effects of vasoactive drugs should not only be based on the increase of arterial blood pressure, but also on the blood flow perfusion of internal organs. The effects of dopamine and metaraminol on the renal function of the patients with septic shock were investigated retrospectively in this study. METHODS: Ninety-eight patients with septic shock were divided into three groups according to the highest infusing rate of metaraminol, with the lightest infusing rate of (0.1 - 0.5, 0.6 - 1.0, > 1.0) microgxkg(-1)xmin(-1) in group A, B and C respectively. Urine output, mean arterial blood pressure (MAP), heart rate (HR), urine output, blood urea nitrogen (BUN), creatinine (CRE), urine albumin (U-ALB), urine beta(2)-microglubulin (Ubeta(2)-MG) and Apache III scores were recorded. RESULTS: Before antishock therapy, hypotension, tachycardia and oliguria occurred to all the 98 patients with septic shock and CRE, BUN, U-ALB, Ubeta(2)-MG and Apache III scoring were abnormal in most cases. With the antishock therapy, MAP, HR, urine output, BUN and CRE in all patients returned gradually to normal (P < 0.05 or < 0.01 compared to those before antishock therapy). U-ALB, Ubeta(2)-MG output and Apache III scoring also reverted but remained abnormal (P < 0.01 compared to those before antishock therapy). No statistically significant differences in the changes of these indices with the time existed among the three groups (P > 0.05). CONCLUSION: Dopamine and metaraminol when applied to the patients with septic shock could effectively maintain the circulatory stability and promote restoration of renal function.