Feasibility study for the rapid determination of the amylose content in starch by near-infrared spectroscopy.

Near-infrared (NIR) spectroscopy was used to determine the amylose content in six different starches, whose declared amylose contents ranged from 2 to 95% m/m. The amylose content of starches can vary considerably between batches depending on growth conditions and time of harvesting. An NIR calibration model was developed for amylose using simple laboratory produced mixtures of amylose and amylopectin in different ratios. The spectral region at 1700-1800nm showed a good correlation to the amylose content of these mixtures. A simple absorbance ratio calibration model using standard normal variate and first derivative pre-treated spectra gave a root mean standard error of prediction of 1.2% m/m. Application to real samples gave amylose contents in reasonable agreement with the average values stated by the supplier. NIR spectroscopy provides a rapid and non-destructive method for the quantitative determination and standardisation of amylose in starch and could make a suitable alternative to traditional techniques, such as complex formation of starch with iodine or n-butanol.     

Quantitative variability in the biodistribution and in toxinokinetic studies of the three main alpha toxins from the Androctonus australis hector scorpion venom.

Scorpion stings represent a medical problem in numerous countries. The scorpion Androctonus australis hector produces three alpha toxins (Aah I to III), which are responsible for most of the lethality in mammals. These toxins act on sodium channel and do not cross-react immunologically. We used RIA and ELISA to measure the concentrations of these three toxins in plasma, urine and different organs after i.v. and s.c. injections of water extracts of venoms in rabbits or mice. In both animals, the toxins rapidly appeared in plasma after s.c. injection as it was previously described for the whole venom. However, the toxins disappeared from the blood more quickly than did other main components of the venom. Thus, serotherapy must be initiated immediately to prevent the toxin from reaching its target. We also detected the toxins in urine, kidneys, heart and lungs, but not in the brain. However, the concentration of Aah II was always lower than that of Aah I. Analysis of five samples of venom collected in different areas of southern Tunisia showed that a large polymorphism exists for the three toxins. This is yet another difficulty for serotherapy as there is no cross-antigenicity between them.     

Establishment of a formal program for retinoblastoma: Feasibility of clinical coordination across borders and impact on outcome

Retinoblastoma is an ocular tumor that occurs in young children, in either heritable or sporadic manner. The relative rarity of retinoblastoma, and the need for expensive equipment, anesthesia, and pediatric ophthalmologic expertise, are barriers for effective treatment in developing countries. Also, with an average age‐adjusted incidence of two to five cases per million children, patient number limits development of local expertise in countries with small populations. Lebanon is a small country with a population of approximately 4.5 million. In 2012, a comprehensive retinoblastoma program was formalized at the Children's Cancer Institute (CCI) at the American University of Beirut Medical Center, and resources were allocated for efficient interdisciplinary coordination to attract patients from neighboring countries such as Syria and Iraq, where such specialized therapy is also lacking. Through this program, care was coordinated across hospitals and borders such that patients would receive scheduled chemotherapy at their institution, and monthly retinal examinations and focal laser therapy at the CCI in Lebanon. Our results show the feasibility of successful collaboration across borders, with excellent patient and physician adherence to treatment plans. This was accompanied by an increase in patient referrals, which enables continued expertise development. However, the majority of patients presented with advanced intraocular disease, necessitating enucleation in 90% of eyes in unilateral cases, and more than 50% of eyes in bilateral cases. Future efforts need to focus on expanding the program that reaches to additional hospitals in both countries, and promoting early diagnosis, for further improvement of globe salvage rates.     

Training police trainees about ways to manage trauma and loss

For the second year we were invited to be trainers at a training seminar for senior police educators, held in the German Federal Police University and sponsored by the European Police College, hence, having the opportunity to build on their previous applications. We applied exercises (psychoeducation, mindfulness/awareness, journaling, processing in dyads) that introduced in this training and designed to teach officers how to handle exposure to adversities and minimize potential negative consequences. Police officers expect exposure to potentially traumatic incidents, yet, often suffer deeply because of unresolved trauma related to handling horrific events. Our work aimed to open discussion in order to formulate a standard component in training curricula related to teaching police trainees ways to effectively handle and process trauma.     

Mechanical and physical properties of silorane and methacrylate-based composites

ObjectivesThis study measured the degree of conversion (DC), sorption, solubility and microhardness of methacrylate (Filtek Z250 and Filtek Z350XT) and silorane-based composites (Filtek P90).MethodsDC was measured using near infrared spectroscopy immediately and 24 h after the photoactivation. Sorption and solubility measurements were performed after 24 h, 4 weeks and 12 weeks of storage in water. Knoop microhardness was measured after 24 h and after thermal cycling. The data were statistically analyzed using ANOVA followed by Tukey's, Tamhane or paired t-tests (α = 0.05).ResultsThe DC for P90 (37.22 ± 1.46) was significantly lower than the Z250 (71.44 ± 1.66) and Z350 (71.76 ± 2.84). Water sorption was highest in the Z250 and lowest in the P90. All the tested composites exhibited similar values after 24 h of immersion, and no significant differences were observed. No significant differences were observed between the solubilities of the P90 composite (12 weeks) and the Z250 or Z350 composites (4 weeks). KHN values were less elevated for the P90 composite and similar for the Z250 and Z350 composites. An effect of thermal cycling on KHN values was observed for all the composites (p < 0.001).ConclusionsSilorane produced the lowest DC and KHN values and exhibited lower water sorption and solubility compared to methacrylate-based composites. These differences suggest that silorane composites exhibit better hydrolytic stability after 3 months of water immersion compared to conventional methacrylate-based composites.Clinical significanceSilorane had higher hydrolytic stability after 3 months of water immersion than the methacrylate-based resins, despite the lower values of DC and KHN recorded.