Mechanistic pathways for the degradation of SMX drug and floatation of degraded products using F–Pt co-doped TiO2 photocatalysts

This work presents smart pathways to enhance the photocatalytic activity of TiO₂via co-doping with fluorine (F) and platinum (Pt) to form F–Pt co-doped TiO₂ photocatalysts and investigates the unique and unusual fluorination of the floated products. Our investigations indicate that the crystalline structure of the photocatalysts was a mixture of anatase and brookite phases and that the nanoparticles of the synthesized nanocomposites had nanometric sizes (4–25 nm). The F–Pt co-doped TiO₂ nano-photocatalysts demonstrated degradation of sulfamethoxazole (SMX) drug of >93% within 90 min under direct solar light and 58% degradation within 360 min under a solar simulator. Thus, co-doping TiO₂ with F and Pt atoms to form F–Pt co-doped TiO₂ nanocomposite is an efficient pathway to achieve high photocatalytic performance escorted with the formation of floating metal-fluoropolymer, unlike pristine TiO₂ which has less photocatalytic degradation and no generation of a floating polymer. Our photocatalytic protocol demonstrates that the degradation of SMX started with redox reactions of oxygen and water absorbed on the surface of the prepared nanocomposites to form superoxide anions (O₂˙⁻) and hydroxy radicals (˙OH) which have oxidation superpower. The resultant products were subsequently fluorinated by fluoride radical ions and floated as metal-fluoropolymer.

This work presents smart pathways to enhance the photocatalytic activity of TiO₂via co-doping with fluorine (F) and platinum (Pt) to form F–Pt co-doped TiO₂ photocatalysts and investigates the unique and unusual fluorination of the floated products.     

Sonographic Prediction of Scar Dehiscence in Women with Previous Cesarean Section

Purpose

To estimate the risk of uterine dehiscence/rupture in women with previous cesarean section (CS) by comparing the thickness of lower uterine segment (LUS) and myometrium with trans-abdominal (TAS) and trans-vaginal sonography (TVS).

Method

In this case-control study, in 100 pregnant women posted for elective CS (with or without previous CS; group 1 and group 2 respectively), the thickness of LUS and myometrium was measured sonographically (TAS and TVS). Intra-operatively, LUS was graded (grades I–IV), and its thickness was measured with calipers. The primary outcome of the study was correlation between echographic measurements (TAS and TVS) and features of LUS (grades I–IV) at the time of CS. Secondary outcomes were correlation between myometrial thickness, number of previous CS, and inter-delivery interval with LUS (grades I–IV).

Results

Sonographic measurements of LUS and myometrium were significantly different between the two groups (both TAS and TVS p value = 0.000 each). However, the number of previous CS (p = 0.440) and inter-delivery interval (p = 0.062) had no statistically significant correlation with thickness of LUS.

Conclusions

Sonographic evaluation of LUS scar and myometrial thickness (both with TAS and TVS) is a safe, reliable, and non-invasive method for predicting the risk of scar dehiscence/rupture. Specific guidelines for TOLAC, after sonographic assessment of women with previous CS, are need of the hour.Keyword: Transabdominal ultrasonography, Transvaginal ultrasonography, Cesarean section, Pregnancy, Cesarean scar     

Inhaled iloprost reverses vascular remodeling in chronic experimental pulmonary hypertension

RATIONALE: Inhaled iloprost is an effective therapy for pulmonary arterial hypertension (PAH). However, no study to date has addressed the effects of inhaled iloprost on changes to pulmonary vascular structure that occur in PAH. OBJECTIVES: The present study was designed to investigate chronic antiremodeling effects of inhaled iloprost in monocrotaline (MCT)-induced PAH in rats. Methods: Four weeks after a single injection of MCT, after full establishment of PAH, rats were nebulized with iloprost at a dose of 6 microg . kg(-1) . day(-1), or underwent sham nebulization with saline. RESULTS: After 2 weeks of inhalation therapy, right ventricular pressure and pulmonary vascular resistance were reversed in rats treated with iloprost, but not in sham-treated control animals. Systemic arterial pressure was unaffected. In addition, right heart hypertrophy, the degree of pulmonary artery muscularization, and the medial wall thickness of intraacinar pulmonary arteries regressed in response to iloprost. Furthermore, the MCT-induced increase in matrix metalloproteinase-2 and -9 activities and tenascin-C expression was suppressed. CONCLUSIONS: We conclude that the inhalation of iloprost reverses PAH and vascular structural remodeling in MCT-treated rats. This regimen suggests the possibility of an antiremodeling therapy in PAH.     

Evaluation of plasmid DNA stability against ultrasonic shear stress and its in vitro delivery efficiency using ionic liquid [Bmim][PF6]

The hydrophobic ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate [Bmim][PF₆] forms nanostructures with negatively charged plasmid DNA through electrostatic interactions. The formation of plasmid DNA/IL nanostructures was confirmed by measuring the zeta potential of plasmid DNA as well as plasmid DNA/IL nanostructures. The zeta potential of the nanostructures was positive, although plasmid DNA is negatively charged. The positive zeta potential is due to the complexation between plasmid DNA and positively charged ionic liquid [Bmim][PF₆]. The ability of ionic liquid [Bmim][PF₆] to protect plasmid DNA against ultrasonic shear stress was also investigated using an agarose gel electrophoretic assay and showed that ionic liquid stabilizes plasmid DNA against ultrasonication. The plasmid DNA and plasmid DNA/IL nanostructures were subjected to ultrasonic shear stress for different time periods and the biological functionality of pristine plasmid DNA (i.e., expression of the eGFP gene) as well as the self-assembled nanostructures was investigated in vitro using three different cell lines, COS7, HEK293 and HeLa. Ionic liquid [Bmim][PF₆] protected the plasmid DNA against ultrasonic shear stress and also enhanced gene transfection efficiency in vitro. Furthermore, the cytotoxicity of ionic liquid [Bmim][PF₆] was assayed in vitro using all three cell lines and the toxicity was very low. Therefore, the ionic liquid [Bmim][PF₆] stabilizes plasmid DNA against ultrasonic shear stress and also enhances its in vitro delivery efficiency.

The hydrophobic ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate [Bmim][PF₆] forms ultrasonically stable and functional nanostructures with negatively charged plasmid DNA through electrostatic interactions.     

Tetralogy of Fallot with restrictive ventricular septal defect by accessory tricuspid leaflet tissue

In tetralogy of Fallot septal defect is usually large because of malalignment of outlet septum, restrictive defect has been reported rarely. We present a case of tetralogy of Fallot with accessory tricuspid leaflet tissue restricting ventricular septal defect. The report includes echocardiographic and catheter images of this rare presentation of tetralogy of Fallot.