Metabolism of Butoxyethanol in excised human skin in vitro

Glycol ethers are widely used in industrial and household applications because their chemical and physical properties make them versatile solvents, miscible with both water and organic media. Due to the ease with which the glycol ethers are absorbed through the skin and the potential for development of adverse health effects it is important to understand the extent to which local metabolism can contribute to local and systemic toxicity. Sections of previously frozen, full thickness excised human skin samples were placed on transwell supports and placed with the underside of the skin in contact with receptor fluid. The skin surface was dosed with 115.2 mg of neat butoxyethanol and the absorption and metabolism of butoxyethanol to butoxyacetic acid monitored over time. In total 64.94 ± 0.04 mg of butoxyethanol or its metabolites were removed from the surface of the skin at 24 hours, representing the equivalent of 56% of the applied dose, the equivalent of 17.5% of the applied dose was recovered from the receiver fluid, 3% from within the skin and the remaining 23.5% of the dose was lost to the atmosphere through evaporation. After 24 hours a total of 31.5 μg of butoxyacetic acid had been produced representing approximately 0.03% of the applied dose. Therefore approximately 0.16% (31.5 μg as a percentage of the total amount of butoxyethanol reaching the receiver fluid (20.17 mg) of the absorbed butoxyethanol was metabolised to butoxyacetic acid during its passage through the skin. This suggested that, although enzyme activities capable of converting butoxyethanol to butoxyacetic acid are present in skin, metabolic conversion during percutaneous absorption was small and systemic exposure to the parent compound rather than the metabolite would occur following dermal exposure to butoxyethanol. This experiment demonstrates that it is possible to maintain metabolic activity in skin samples in an in vitro set up for short, but experimentally useful, period.Peer reviewe

The influence of water mixtures on the dermal absorption of glycol ethers

Original article can be found at: http://www.sciencedirect.com/science/journal/0041008X Copyright Elsevier Inc. DOI: 10.1016/j.taap.2006.09.019Glycol ethers are solvents widely used alone and as mixtures in industrial and household products. Some glycol ethers have been shown to have a range of toxic effects in humans following absorption and metabolism to their aldehyde and acid metabolites. This study assessed the influence of water mixtures on the dermal absorption of butoxyethanol and ethoxyethanol in vitro through human skin. Butoxyethanol penetrated human skin up to sixfold more rapidly from aqueous solution (50%, 450 mg/ml) than from the neat solvent. Similarly penetration of ethoxyethanol was increased threefold in the presence of water (50%, 697 mg/ml). There was a corresponding increase in apparent permeability coefficient as the glycol ether concentration in water decreased. The maximum penetration rate of water also increased in the presence of both glycol ethers. Absorption through a synthetic membrane obeyed Fick's Law and absorption through rat skin showed a similar profile to human skin but with a lesser effect. The mechanisms for this phenomenon involves disruption of the stratum corneum lipid bilayer by desiccation by neat glycol ether micelles, hydration with water mixtures and the physicochemical properties of the glycol ether–water mixtures. Full elucidation of the profile of absorption of glycol ethers from mixtures is required for risk assessment of dermal exposure. This work supports the view that risk assessments for dermal contact scenarios should ideally be based on absorption data obtained for the relevant formulation or mixture and exposure scenario and that absorption derived from permeability coefficients may be inappropriate for water-miscible solvents.Peer reviewe

Development of value added tea bags and capsules of Artemisia Annua Anamed (A3) whole plant for malaria treatment

Malaria is one of the most serious diseases of global public health importance. Artemisinin-based Combination Therapy (ACT) has been adopted as the first-line treatment of uncomplicated malaria in Nigeria. However, ACTs are expensive; hence the need for production of Artemisia plants as a local alternative. Artemisia Annua Anamed (A-3) cultivar seeds were obtained from REAP in Kenya and propagated in Ilorin, Nigeria; based on the guidelines of Anamed International, REAP and WHO for growing, harvesting, and processing to value added products. Propagation to budding/harvesting took 4 months and fresh leaves were processed to dark green dried leaves which was developed to value added products of tea bags and powdered capsules following the Noble Icon NAFDAC approved procedures and equipment; and Now Food University in USA procedures and equipment respectively. Each tea bag of A-3 contained 2.5g of pulverized dried leaves while each capsule contained 500mg of powdered dried leaves based on Anamed International dosage recommendations. Several studies supported the use of artemisia annua tea and capsules for the treatment of malaria pointing out that flavonoids existing in the leaves and stem considerably enhance the interest of its tea preparation and powdered leave capsules that are usable for rectal administration. It is recommended that there is the need to train the rural community people who are already using herbal medicine; and unable to reach or afford costly pharmaceutical ACT in the growing and development of the dried A-3 leaves as herb tea for malaria prevention and treatment. There is also the need for further studies to determine the active contents in the developed herb tea and the powdered capsules in order to be able to use them for treating malaria.Key Words: Artemisia Annua Anamed, Herb Tea, Capsules, Malaria, Whole Plan

Nutritional characterization of grain amaranth grown in Nigeria for food security and healthy living

Amaranths cruentus is a flowering plant species that yields the nutritious staple amaranth grain. Zinc in grain amaranth is reported to contribute to boosting the immune system and iron is required by enzymes for oxygen metabolism. This study is to exploit the multi-benefits of amaranth which ranged from improved well-being to recovery of severely malnourished children; increased body mass index of people formerly wasted by HIV/AIDS; environmental adaptability, yield, and recipes   development. The study focused on determining the nutritional and medicinal   properties of grain amaranth cultivar obtained from Rural Extension with Africa Poor  (REAP) in Kenya which was propagated in Kwara State, Nigeria, harvested after 65  days, and prepared as samples for the study. Standard procedures of Association of  Official Analytical Chemists (AOAC), Atomic Absorption Spectrophotometer, Flame  Photometer, and Spectrophotometer were used to determine the    macro/micronutrients in the grains. Results revealed that the grains contained   protein, lipid, Iron-66 mg/100g, Zinc-11.34 mg/100g, Calcium-78.7 mg/100g,  Manganese-37.1 mg/100g, Magnesium-2845 mg/100g, Potassium-400 mg/100g; Thiamine-0.2756 mg (%), Riboflavin-0.734 mg (%) and Niacin-1.042. More   research efforts are needed on growing, inclusion in diets, consumer behavior and  market acceptability of Amaranth cruentus based products in order to contribute to the efforts of addressing food security, poverty reduction, nutritional, and medicinal needs of vulnerable communities.Keywords: Complementary Food, Cultivar, Macro/micronutrients, Recipes,  Well-being

Coordination‐cage‐catalysed hydrolysis of organophosphates : cavity‐ or surface‐based?

The hydrophobic central cavity of a water‐soluble M8L12 cubic coordination cage can accommodate a range of phospho‐diester and phospho‐triester guests such as the insecticide “dichlorvos” (2,2‐dichlorovinyl dimethyl phosphate) and the chemical warfare agent analogue di(isopropyl) chlorophosphate. The accumulation of hydroxide ions around the cationic cage surface due to ion‐pairing in solution generates a high local pH around the cage, resulting in catalysed hydrolysis of the phospho‐triester guests. A series of control experiments unexpectedly demonstrates that—in marked contrast to previous cases—it is not necessary for the phospho‐triester substrates to be bound inside the cavity for catalysed hydrolysis to occur. This suggests that catalysis can occur on the exterior surface of the cage as well as the interior surface, with the exterior‐binding catalysis pathway dominating here because of the small binding constants for these phospho‐triester substrates in the cage cavity. These observations suggest that cationic but hydrophobic surfaces could act as quite general catalysts in water by bringing substrates into contact with the surface (via the hydrophobic effect) where there is also a high local concentration of anions (due to ion pairing/electrostatic effects)

Eimeria species occurrence varies between geographic regions and poultry production systems and may influence parasite genetic diversity

Coccidiosis is one of the biggest challenges faced by the global poultry industry. Recent studies have highlighted the ubiquitous distribution of all Eimeria species which can cause this disease in chickens, but intriguingly revealed a regional divide in genetic diversity and population structure for at least one species, Eimeria tenella. The drivers associated with such distinct geographic variation are unclear, but may impact on the occurrence and extent of resistance to anticoccidial drugs and future subunit vaccines. India is one of the largest poultry producers in the world and includes a transition between E. tenella populations defined by high and low genetic diversity. The aim of this study was to identify risk factors associated with the prevalence of Eimeria species defined by high and low pathogenicity in northern and southern states of India, and seek to understand factors which vary between the regions as possible drivers for differential genetic variation. Faecal samples and data relating to farm characteristics and management were collected from 107 farms from northern India and 133 farms from southern India. Faecal samples were analysed using microscopy and PCR to identify Eimeria occurrence. Multiple correspondence analysis was applied to transform correlated putative risk factors into a smaller number of synthetic uncorrelated factors. Hierarchical cluster analysis was used to identify poultry farm typologies, revealing three distinct clusters in the studied regions. The association between clusters and presence of Eimeria species was assessed by logistic regression. The study found that large-scale broiler farms in the north were at greatest risk of harbouring any Eimeria species and a larger proportion of such farms were positive for E. necatrix, the most pathogenic species. Comparison revealed a more even distribution for E. tenella across production systems in south India, but with a lower overall occurrence. Such a polarised region- and system-specific distribution may contribute to the different levels of genetic diversity observed previously in India and may influence parasite population structure across much of Asia and Africa. The findings of the study can be used to prioritise target farms to launch and optimise appropriate anticoccidial strategies for long-term control

Economic Impact of Alternative Growth Promotant Strategies on the United States Beef Industry.

28 p

Fabrication of highly efficient grating band-pass filters and their applications in soliton propagation system

We report here fabrication of highly efficient in-fiber grating bandpass filters using the established UV-side- exposure technique. Various combinations of passband/stopband and transmission/rejection of single- and multi-channel filters have been produced in hydrogenated standard telecom, high Ge-doped and B/Ge-codoped fibers. Up to > 60 dB rejection stopbands ranging from -2 nm to 55 nm, and passbands with 0.02 nm - 3 nm linewidths and transmissivity up to > 90% have been achieved with these devices. By concatenating several structures, a bandpass filter has been demonstrated with a combination of a 0.16 nm passband centered in a approximately 35 nm stopband, representing the highest reported finesse of 220 for any multi-nanometer stopband filter. We also report the first application of a grating bandpass filter for suppressing timing jitter in soliton propagation system, enabling transmission of 10 ps solitons over a distance of 2700 km

Crypto-unitary forms of quantum evolution operators

For the description of quantum evolution, the use of a manifestly time-dependent quantum Hamiltonian $\mathfrak{h}(t) =\mathfrak{h}^\dagger(t)$ is shown equivalent to the work with its simplified, time-independent alternative $G\neq G^\dagger$. A tradeoff analysis is performed recommending the latter option. The physical unitarity requirement is shown fulfilled in a suitable ad hoc representation of Hilbert space.Comment: 15 p

Photoassociation spectroscopy of cold calcium atoms

Photoassociation spectroscopy experiments on 40Ca atoms close to the dissociation limit 4s4s 1S0 - 4s4p 1P1 are presented. The vibronic spectrum was measured for detunings of the photoassociation laser ranging from 0.6 GHz to 68 GHz with respect to the atomic resonance. In contrast to previous measurements the rotational splitting of the vibrational lines was fully resolved. Full quantum mechanical numerical simulations of the photoassociation spectrum were performed which allowed us to put constraints on the possible range of the calcium scattering length to between 50 a_0 and 300 a_0