Irrigation - does it affect post-operative pain?

DESIGN: A randomised control trial involving eighty patients who were blindly allocated into four different groups for different disinfection and irrigation methods on lower permanent molars. The patients were treated by one experienced endodontist across two visits. The four methods of irrigation used were: 1. Conventional irrigation 2. Sonic irrigation activation system 3. Irradiation with a 980 nm diode laser and conventional irrigation 4. Irradiation with a 980 nm diode laser and sonic irrigation activation system Pain levels were then assessed postoperatively at 8 h, 24 h, 48 h and 7 days following access and chemomechanical preparation at the first visit. CASE SELECTION: Eighty patients who visited the Endodontic Department at Biruni University were included in the study. Those who were included were healthy adults, experiencing moderate to severe pain (self-scored from 4 to 10, based on a 0 to 10 pain scale) at the start of treatment and those who were given a dental diagnosis of 'symptomatic apical periodontitis' with a negative cold test in a mandibular molar. DATA ANALYSIS: Qualitative data was analysed using a chi-square test, Fisher's exact chi-square test and Fisher-Freeman-Halton exact test. The Kruskal-Wallis test and Willcoxon test were used to assess inter-group and intra-group parameters. RESULTS: The study found that patients in all groups experienced a statistically significant decrease in pain levels postoperatively. However, different irrigation methods resulted in no statistically significant differences in pain levels. There were also no statistically significant differences based on gender or age. Statistical significance was reached when p < 0.05. CONCLUSIONS: The use of sonic irrigation activation and irradiation with a 980 nm diode laser did not significantly reduce post-operative pain in adult mandibular molars undergoing endodontic treatment when compared to conventional irrigation methods.

The influence of hypoxia and energy depletion on the response of endothelial cells to the vascular disrupting agent combretastatin A-4-phosphate.

Combretastatin A-4 phosphate (CA4P) is a microtubule-disrupting tumour-selective vascular disrupting agent (VDA). CA4P activates the actin-regulating RhoA-GTPase/ ROCK pathway, which is required for full vascular disruption. While hypoxia renders tumours resistant to many conventional therapies, little is known about its influence on VDA activity. Here, we found that active RhoA and ROCK effector phospho-myosin light chain (pMLC) were downregulated in endothelial cells by severe hypoxia. CA4P failed to activate RhoA/ROCK/pMLC but its activity was restored upon reoxygenation. Hypoxia also inhibited CA4P-mediated actinomyosin contractility, VE-cadherin junction disruption and permeability rise. Glucose withdrawal downregulated pMLC, and coupled with hypoxia, reduced pMLC faster and more profoundly than hypoxia alone. Concurrent inhibition of glycolysis (2-deoxy-D-glucose, 2DG) and mitochondrial respiration (rotenone) caused profound actin filament loss, blocked RhoA/ROCK signalling and rendered microtubules  CA4P-resistant. Withdrawal of the metabolism inhibitors restored the cytoskeleton and CA4P activity. The AMP-activated kinase AMPK was investigated as a potential mediator of pMLC downregulation. Pharmacological AMPK activators that generate AMP, unlike allosteric activators, downregulated pMLC but only when combined with 2DG and/or rotenone. Altogether, our results suggest that Rho/ROCK and actinomyosin contractility are regulated by AMP/ATP levels independently of AMPK, and point to hypoxia/energy depletion as potential modifiers of CA4P response.

Burden of influenza infection in hospitalised children below 6 months of age and above in Hong Kong from 2005 to 2011.

The World Health Organization recommends vaccination of pregnant women for seasonal influenza that can also protect infants aged below 6 months. We estimated incidence and disease burden of influenza in hospitalised children below and above 6 months of age in Hong Kong during a 6 year period. Discharge diagnoses for all admissions to public Hong Kong Hospital Authority hospitals, recorded in a central computerised database (Clinical Management System, CMS), were analysed for the period April 2005 to March 2011. Incidence estimates of influenza disease by age group were derived from CMS ICD codes 487-487.99. Laboratory-confirmed influenza infections from a single surveillance hospital were then linked to the CMS entries to assess possible over- and under-diagnosis of influenza based on CMS codes alone. Influenza was recorded as any primary or any secondary diagnosis in 1.3% (1158/86,582) of infants aged above 6 days to below 6 months and 4.3% (20,230/471,482) of children above 6 days to below 18 years. The unadjusted incidence rates per 100,000 person-years based on any CMS diagnosis of influenza in all admission to Hong Kong public hospitals were 627 in the below 2 months of age group and 1762 in the 2 month to below 6 month group. Incidence of hospitalisation for influenza in children was highest from 2 months to below 6 months. In the absence of vaccines for children below 6 months of age, effective vaccination of pregnant women may have a significant impact on reducing influenza hospitalisations in this age group.