Effect of water-in-oil microemulsions and lamellar liquid crystalline systems on the precorneal tear film of albino New Zealand rabbits

The aim of this study is to investigate the effect of phase transition water-in-oil (w/o) microemulsions (ME) and liquid crystalline systems (LC) on the precorneal tear film (PCTF). The study used six albino NZ rabbits and monitored the integrity and stability of the PCTF before and after instillation of test formulations. The effects were evaluated by assessment of the PCTF lipid layer using interferometry, tear evaporation rate measurements, and indirect estimation of tear volume. Ocular application of test formulations changed the appearance of the PCTF lipid layer, indicating lipid layer disruption. The recovery time was longer in case of ME compared with an aqueous solution (SOL). The tear evaporation rate was increased after application of both ME and LC systems compared with the SOL, with the LC system showing the greatest effect. Tear volume measurement results revealed minimal changes associated with the instillation of both ME systems. Whilst phase transition w/o ME systems can interact with the PCTF lipid layer in albino New Zealand rabbits, their effect on the volume of resident tears was found to be minimal

Systematic review and meta-analysis of the value of initial biomarkers in predicting adverse outcome in febrile neutropenic episodes in children and young people with cancer

Background: Febrile neutropenia is a frequently occurring and occasionally life-threatening complication of treatment for childhood cancer. Many biomarkers have been proposed as predictors of adverse events. We aimed to undertake a systematic review and meta-analysis to summarize evidence on the discriminatory ability of initial serum biomarkers of febrile neutropenic episodes in children and young people. Methods: This review was conducted in accordance with the Center for Reviews and Dissemination Methods, using three random effects models to undertake meta-analysis. It was registered with the HTA Registry of systematic reviews, CRD32009100485. Results: We found that 25 studies exploring 14 different biomarkers were assessed in 3,585 episodes of febrile neutropenia. C-reactive protein (CRP), pro-calcitonin (PCT), and interleukin-6 (IL6) were subject to quantitative meta-analysis, and revealed huge inconsistencies and heterogeneity in the studies included in this review. Only CRP has been evaluated in assessing its value over the predictive value of simple clinical decision rules. Conclusions: The limited data available describing the predictive value of biomarkers in the setting of pediatric febrile neutropenia mean firm conclusions cannot yet be reached, although the use of IL6, IL8 and procalcitonin warrant further study

Could vitamin D3 be effective in prevention of risk of preeclampsia among pregnant women?

Background Preeclampsia, a pregnancy disease marked by high blood pressure and proteinuria, affects 2–8% of all pregnancies. Preeclampsia can be life-threatening for both the mother and the fetus and is still a significant cause of maternal and neonatal morbidity and mortality. The goal of this study was to assess if there was a link between maternal serum vitamin D3 levels and the severity of preeclampsia. Patients and methods A case–control study was conducted on 70 pregnant women at Shebin El Kom Teaching Hospital. All pregnant women were divided into two groups: group A included 30 apparently healthy pregnant women (control group) and group B included 40 pregnant patients with preeclampsia (patient group). Results The serum vitamin D levels of patients with preeclampsia were considerably lower than those of the control group. The serum level of vitamin D in patients with mild preeclampsia was substantially higher than in patients with severe preeclampsia. Conclusion Vitamin D deficiency in the mother is a significant risk factor for preeclampsia. Vitamin D deficiency was found to be associated with a higher risk of preeclampsia

Interactions of surfactants (edge activators) and skin penetration enhancers with liposomes

Incorporating edge activators (surfactants) into liposomes was shown previously to improve estradiol vesicular skin delivery; this phenomenon was concentration dependent with low or high concentrations being less effective. Replacing surfactants with limonene produced similar behaviour, but oleic acid effects were linear with concentration up to 16% (w/w), beyond which it was incompatible with the phospholipid. This present study thus employed high sensitivity differential scanning calorimetry to probe interactions of additives with ipalmitoylphosphatidylcholine (DPPC) membranes to explain such results. Cholesterol was included as an example of a membrane stabiliser that removed the DPPC pre-transition and produced vesicles with a higher transition temperature (Tm). Surfactants also removed the lipid pre-transition but reduced Tm and co-operativity of the main peak. At higher concentrations, surfactants also formed new species, possibly mixed micelles with a lower Tm. The formation of mixed micelles may explain reduced skin delivery from liposomes containing high concentrations of surfactants. Limonene did not remove the pre-transition but reduced Tm and co-operativity of the main peak, apparently forming new species at high concentrations, again correlating with vesicular delivery of estradiol. Oleic acid obliterated the pre-transition. The Tm and the co-operativity of the main peak were reduced with oleic acid concentrations up to 33.2 mol%, above which there was no further change. At higher concentrations, phase separation was evident, confirming previous skin transport findings