Glucose and leucine kinetics in idiopathic ketotic hypoglycaemia.

AIMS: To investigate glucose and leucine kinetics in association with metabolic and endocrine investigations in children with ketotic hypoglycaemia (KH) in order to elucidate the underlying pathophysiology. METHODS: Prospective interventional study using stable isotope tracer in nine children (mean age 4.23 years, range 0.9-9.8 years; seven males) with KH and 11 controls (mean age 4.57 years, range 0.16-12.3 years; four males). RESULTS: Plasma insulin levels were significantly lower in KH compared to subjects in the non-KH group. Plasma ketone body levels were significantly higher in KH than in non-KH. Basal metabolic rate was significantly higher in subjects with KH (45.48+/-7.41 v 31.81+/-6.72 kcal/kg/day) but the respiratory quotients were similar in both groups (KH v non-KH, 0.84+/-0.05 v 0.8+/-0.04. Leucine oxidation rates were significantly lower in children with KH (12.25+/-6.25 v 31.96+/-8.59 micromol/kg/h). Hepatic glucose production rates were also significantly lower in KH (3.84+/-0.46 v 6.6+/-0.59 mg/kg/min). CONCLUSIONS: KH is caused by a failure to sustain hepatic glucose production rather than by increased glucose oxidation rates. Energy demand is significantly increased, whereas leucine oxidation is reduced.     

Experimental retinal tolerance to very low viscosity silicone oil (100 cs) as a vitreous substitute compared to higher viscosity silicone oil (5000 cs)

We evaluated the toxicity of very low viscosity (100 centistokes) and higher viscosity silicone oil (5000 centistokes) in rabbit eyes as a short-to-long-term postoperative vitreous substitute (6 weeks to 5 months). Emulsification of 100-cs and 5000-cs silicone oil did not occur in eyes which were followed for as long as 5 months. No toxic effects to retinal cells were detected by light or electron microscopy. Because no toxic effects were seen with 100-cs silicone oil, it can be used in an outpatient setting as a short-term postoperative tamponading agent. Electroretinographic responses of silicone-injected eyes were normal.     

Innovative pulmonary targeting of terbutaline sulfate-laded novasomes for non-invasive tackling of asthma: statistical optimization and comparative in vitro/in vivo evaluation

Asthma represents a globally serious non-communicable ailment with significant public health outcomes for both pediatrics and adults triggering vast morbidity and fatality in critical cases. The β₂-adrenoceptor agonist, terbutaline sulfate (TBN), is harnessed as a bronchodilator for monitoring asthma noising symptoms. Nevertheless, the hepatic first-pass metabolism correlated with TBN oral administration mitigates its clinical performance. Likewise, the regimens of inhaled TBN dosage forms restrict its exploitation. Consequently, this work is concerned with the assimilation of TBN into a novel non-phospholipid nanovesicular paradigm termed novasomes (NVS) for direct and effective TBN pulmonary targeting. TBN-NVS were tailored based on the thin film hydration method and Box-Behnken design was applied to statistically optimize the formulation variables. Also, the aerodynamic pattern of the optimal TBN-NVS was explored via cascade impaction. Moreover, comparative pharmacokinetic studies were conducted using a rat model. TBN elicited encapsulation efficiency as high as 70%. The optimized TBN-NVS formulation disclosed an average nano-size of 223.89 nm, ζ potential of −31.17 mV and a sustained drug release up to 24 h. Additionally, it manifested snowballed in vitro lung deposition behavior in cascade impactor with a fine particle fraction of 86.44%. In vivo histopathological studies verified safety of intratracheally-administered TBN-NVS. The pharmacokinetic studies divulged 3.88-fold accentuation in TBN bioavailability from the optimum TBN-NVS versus the oral TBN solution. Concisely, the results proposed that NVS are an auspicious nanovector for TBN pulmonary delivery with integral curbing of the disease owing to target specificity.     

Bioactive diterpenes and other constituents of Croton steenkampianus

A new indanone derivative (1) and two new diterpenoids (2 and 3), together with three known flavonoids, have been isolated from an ethanol extract of the leaves of Croton steenkampianus. The structure of 2 was solved by single-crystal X-ray diffraction analysis, whereas those of 1 and 3 were established mainly by 1D and 2D NMR spectroscopic methods. The isolated compounds were tested for their antiplasmodial activity and cytotoxicity. Antiplasmodial assays against chloroquine-susceptible strains (D10 and D6) and the chloroquine-resistant strains (Dd2 and W2) of Plasmodium falciparum showed that compound 2 gave moderate activities at 9.1-15.8 μM, while none of the compounds were cytotoxic against Vero cells.     

Radon activity concentrations and effective doses in ancient Egyptian tombs of the Valley of the Kings.

Radon concentrations and equilibrium factors were measured in three pharaonic tombs during the year 1998. The tombs, which are open to the public are located in a limestone wadi on the West Bank of the River Nile at Luxor, 650 km south of Cairo. The radon activity concentration and equilibrium factor were measured monthly by two-integral nuclear track detectors (bare and diffusion detectors). Seasonal variation of radon concentrations, with summer maximum and winter minimum were observed in all tombs investigated. The yearly mean radon activity concentrations insidc the tombs ranged from 540 to 3115 Bq m(-3). The mean equilibrium factor over a year was found to be 0.25 and 0.32 inside and at the entrance, respectively. Estimated annual effective doses to tour guides ranged from 0.33 to 1.90 mSv, visitors receive doses from 0.65 to 3.80 microSv per visit. The effective dose to tomb workers did not exceed the 20 mSv yr(-1) limit.     

Evaluation of the Radiation Shielding Properties of a Tellurite Glass System Modified with Sodium Oxide

In this study, the X-ray and gamma attenuation characteristics and optical properties of a synthesized tellurite–phosphate–sodium oxide glass system with a composition of (85 − x)TeO₂–10P₂O₅–xNa₂O mol% (where x = 15, 20, and 25) were evaluated. The glass systems we re fabricated by our research group using quenching melt fabrication. The shielding parameters of as-synthesized systems, such as the mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), effective atomic number (Z_eff), half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), and effective electron density (N_eff) in a wide energy range between 15 keV and 15 MeV, were estimated using well-known PHY-X/PSD software and recently developed MIKE software. Herein, the optical parameters of prepared glasses, such as molar volume (V_M), oxygen molar volume (V_O), oxygen packing density (OPD), molar polarizability (αm), molar refractivity (R_m), reflection loss (R_L), and metallization (M), were estimated using MIKE software. Furthermore, the shielding performance of the prepared glasses was compared with that of commonly used standard glass shielding materials. The results show that the incorporation of sodium oxide into the matrix TeO₂/P₂O₅ with an optimum concentration can yield a glass system with good shielding performance as well as good optical and physical properties, especially at low photon energy.     

Correlation of optic nerve sheath diameter measurements by computed tomography and magnetic resonance imaging

BackgroundTraditionally, intracranial pressure is measured by direct ventriculostomy, which is invasive. Noninvasive measures such as bedside ultrasound and magnetic resonance imaging have been advocated and utilized recently to assess the intracranial pressure. The role of this study is to determine the degree of agreement between measurements of the optic nerve sheath diameter by computed tomography (CT) and magnetic resonance imaging (MRI).Materials and MethodsRetrospective chart review of 100 consecutive patients who had both MRI and CT scan of the head from January 1, 2011, until March 31, 2013, at our center was performed. A discrepancy of 0.2 mm between the 2 measurements was set as acceptable difference. The measurements of optic nerve sheath diameter (ONSD) were compared for agreement between the 2 modalities using the method by Bland and Altman.ResultsA total of 100 patients with both MRI and CT scan of the head were selected. Of these 100 patients, 24 were male and 76 were female. The average age was 63 years. No ONSD abnormality was detected in any of the patients. The discrepancy in measurements of the ONSD between CT and MRI in transverse plane was less than the predetermined cut-off value of 0.2 mm. Within-subject variance was estimated at 0.0058 for both CT and MRI.ConclusionComparable results without significant discrepancy as predetermined by the study groups were obtained from CT scan. Measurement of ONSD by CT scan can be used to indirectly asses the intracranial pressure in addition to clinical assessment and other signs of increased intracranial pressure on CT scan.