Pharmacokinetics of articaine hydrochloride and its metabolite articainic acid after subcutaneous administration in red deer (Cervus elaphus)

AIM: To develop and validate a simple and sensitive method using liquid chromatography-mass spectrometry (LC-MS) for quantification of articaine, and its major metabolite articainic acid, in plasma of red deer (Cervus elaphus), and to investigate the pharmacokinetics of articaine hydrochloride and articainic acid in red deer following S/C administration of articaine hydrochloride as a complete ring block around the antler pedicle.

METHODS: The LC-MS method was validated by determining linearity, sensitivity, recovery, carry-over and repeatability. Articaine hydrochloride (40?mg/mL) was administered S/C to six healthy male red deer, at a dose of 1?mL/cm of pedicle circumference, as a complete ring block around the base of each antler. Blood samples were collected at various times over the following 12 hours. Concentrations in plasma of articaine and articainic acid were quantified using the validated LC-MS method. Pharmacokinetic parameters of articaine and articainic acid were estimated using non-compartmental analysis.

RESULTS: Calibration curves were linear for both articaine and articainic acid. The limits of quantifications for articaine and articainic acid were 5 and 10?ng/mL, respectively. Extraction recoveries were >72% for articaine and >68% for articainic acid. After S/C administration as a ring block around the base of each antler, mean maximum concentrations in plasma (C_max) of articaine were 1,013.9 (SD 510.1) ng/mL, detected at 0.17 (SD 0.00) hours, and the C_max for articainic acid was 762.6 (SD 95.4) ng/mL at 0.50 (SD 0.00) hours. The elimination half-lives of articaine hydrochloride and articainic acid were 1.12 (SD 0.17) and 0.90 (SD 0.07) hours, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE: The LC-MS method used for the quantification of articaine and its metabolite articainic acid in the plasma of red deer was simple, accurate and sensitive. Articaine hydrochloride was rapidly absorbed, hydrolysed to its inactive metabolite articainic acid, and eliminated following S/C administration as a ring block in red deer. These favourable pharmacokinetic properties suggest that articaine hydrochloride should be tested for efficacy as a local anaesthetic in red deer for removal of velvet antlers. Further studies to evaluate the safety and residues of articaine hydrochloride and articainic acid are required before articaine can be recommended for use as a local anaesthetic for this purpose.     

Isolation,purification, and biochemical characterization of a novel water soluble protein from Inca peanut (Plukenetia volubilis L.)

A water soluble storage albumin from Inca peanut (IPA) accounted for approximately 25% (w/w) of defatted seed flour weight, representing 31% of the total seed protein. IPA is a 3S storage protein composed of two glycosylated polypeptides, with estimated molecular weights (MW) of 32800 and 34800 Da, respectively. IPA has an estimated sugar content of 4.8% +/- 0.92% (n = 6). IPA is a basic protein (pI of approximately 9.4) and contains all of the essential amino acids in adequate amounts when compared to the FAO/WHO recommended pattern for a human adult. The tryptophan content of IPA is unusually high (44 mg/g of protein), whereas the phenylalanine content is low (9 mg/g of protein). IPA is a highly digestible protein in vitro.     

Development of an efficient protocol for plant regeneration from nodal explants of recalcitrant bamboo (Bambusa arundinacea Retz. Willd) and assessment of genetic fidelity by DNA markers

The present study describes an efficient method for in vitro plant regeneration in B. arundinacea through axillary shoot bud proliferation. Nodal explants were excised, cultured on MS medium containing different concentrations of 6-benzylaminopurine (BAP), kinetin (KIN) (0.5–5.0 mg l^?1) alone and/or in combinations with KIN/BAP (0.5 mg l^?1). The highest frequency (91.5 %) of multiple shoot bud induction with maximum number of shoots (85 shoots/explant) was noticed on MS medium + 3.0 mg l^?1 BAP + 0.5 mg l^?1 KIN. The regenerated multiple shoots were elongated on MS medium + 4.0 mg l^?1 KIN + 2.0 mg l^?1 gibberellic acid (GA₃) with maximum shoot length (4.9 cm). The elongated shoots were transferred to MS medium containing indole-3 butyric acid (IBA; 0.5–5.0 mg l^?1) alone and/or in combination with 0.5 mg l^?1 KIN and BAP. Highest frequency of rooting (75 %) was obtained on half-strength MS medium + 2.0 mg l^?1 IBA + 0.5 mg l^?1 KIN. After hardening, the plantlets were shifted to the green house and subsequently established in the field conditions with 90 % survival rate. random amplified polymorphic DNA (RAPD) markers were used to evaluate the genetic stability of the regenerants. RAPD profiles generated from the regenerated plants were found to be monomorphic, similar to the control. Results confirmed that the regenerated plants were true-to-type in nature and the developed micropropagation protocol could be used for large scale plant production of B. arundinacea.     

Biochemical characterization of amandin,the major storage protein in almond (Prunus dulcis L.)

The almond major storage protein, amandin, was prepared by column chromatography (amandin-1), cryoprecipitation (amandin-2), and isoelectric precipitation (amandin-3) methods. Amandin is a legumin type protein characterized by a sedimentation value of 14S. Amandin is composed of two major types of polypeptides with estimated molecular weights of 42-46 and 20-22 kDa linked via disulfide bonds. Several additional minor polypeptides were also present in amandin. Amandin is a storage protein with an estimated molecular weight of 427,300 +/- 47,600 Da (n = 7) and a Stokes radius of 65.88 +/- 3.21 A (n = 7). Amandin is not a glycoprotein. Amandin-1, amandin-2, and amandin-3 are antigenically related and have similar biochemical properties. Amandin-3 is more negatively charged than either amandin-1 or amandin-2. Methionine is the first essential limiting amino acid in amandin followed by lysine and threonine.     

Pharmacokinetics following intravenous administration and pharmacodynamics of cefquinome in buffalo calves

Disposition following single intravenous injection (2 mg/kg) and pharmacodynamics of cefquinome were investigated in buffalo calves 6–8 months of age. Drug levels in plasma were estimated by high-performance liquid chromatography. The plasma concentration–time profile following intravenous administration was best described by a two-compartment open model. Rapid distribution of cefquinome was evident from the short distribution half-life (t _½α ?=?0.36?±?0.01 h), and small apparent volume of distribution (Vd_area?=?0.31?±?0.008 L/kg) indicated limited drug distribution in buffalo calves. The values of area under plasma concentration–time curve, elimination half-life (t _½β ), total body clearance (Cl_B), and mean residence time were 32.9?±?0.56 μg·h/mL, 3.56?±?0.05 h, 60.9?±?1.09 mL/h/kg, and 4.24?±?0.09 h, respectively. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration of cefquinome were 0.035–0.07 and 0.05–0.09 μg/mL, respectively. A single intravenous injection of 2 mg/kg may be effective to maintain the MIC up to 12 h in buffalo calves against the pathogens for which cefquinome is indicated.     

Immunostimulatory effect of water soluble fraction of Nyctanthes arbortristis leaves on the immune response in Oreochromis mossambicus (Peters)

Use of immunostimulants as a prophylactic measure against diseases in fish is considered as an effective alternative to antibiotic use. Plant‐derived immunostimulants have recently received more attention, as most of them are cost‐effective and eco‐friendly. This study was carried out with the objective of evaluating the possible immunostimulatory activity of intraperitoneally injected water soluble fraction of Nyctanthes arbortristis (an Indian medicinal plant) leaves on (i) specific immunity (antibody response), (ii) nonspecific immunity (Lysozyme activity, ROS production) and (iii) functional immunity in terms of disease resistance against Aeromonas hydrophila in Oreochromis mossambicus. The results of the study showed that all the tested doses (i.e. 3.2, 16, 80 and 400 mg kg^?1) of water soluble fraction of Nyctanthes arbortristis leaves significantly enhanced both primary and secondary antibody responses to heat killed A. hydrophila. Significant enhancement in serum lysozyme activity by all the doses of water soluble fraction was observed on day 10. The lower doses of 3.2 and 16 mg kg^?1 of water soluble fraction alone enhanced intracellular ROS production. Fish treated with both single and double dose of water soluble fraction showed maximum disease resistance. The highest dose (400 mg kg^?1) of water soluble fraction exhibited highest relative per cent survival in both single dose and double dose groups.     

Large scale in vitro propagation of Stevia rebaudiana (bert) for commercial application: Pharmaceutically important and antidiabetic medicinal herb

Stevia rebaudiana is a valuable medicinal plant species and it is being used for the treatment of diabetes. Currently, there is a high demand for raw material of this medicinal herb due to ever increasing diabetes disorder among the population. In order to meet the increased demand an efficient in vitro propagation of S. rebaudiana was established. Nodal explants collected from the field were cultured on MS basal medium fortified with different concentrations of BAP (0.5-3.0 mg/l) and KIN (0.5-3.0 mg/l) individually for shoot bud induction. In vitro derived nodal buds were cultured on MS medium supplemented with different concentrations (0.5-3.0 mg/l) of BAP and KIN for multiple shoot bud regeneration. In the second experiment, in vitro derived buds were placed on MS medium supplemented with different concentrations of BAP (0.5-3.0 mg/l) in combination with 0.5 mg/l IAA or IBA or NAA for shoot bud multiplication. The highest frequency (94.50%) of multiple shoot regeneration with maximum number of shoots (15.69 shoots/explant) was noticed on MS medium supplemented with 1.0 mg/l BAP. For large scale plant production, in vitro derived nodal bud explants were cultured on MS medium fortified with 1.0 mg/l BAP, in which about 123 shoots/explant were obtained after three subcultures on the same media composition. Elongated shoots (>2 cm) dissected out from the in vitro proliferated shoot clumps were cultured on half-strength MS medium containing different concentrations of NAA (0.1-0.5 mg/l) and/or MS medium fortified with various concentrations (0.5-2.0 mg/l) of auxins (NAA, IAA and IBA) for root induction. Highest frequency of rooting (96%) was noticed on half-strength MS medium augmented with 0.4 mg/l NAA. The rooted plantlets were successfully transferred into plastic cups containing sand and soil in the ratio of 1:2 and subsequently established in the greenhouse. The present in vitro propagation protocol would facilitate an alternative method for rapid and large-scale production of this important antidiabetic medicinal plant.     

Risk factors in relation to human deaths and other tsunami (2004) impacts in Sri Lanka: the fishers'‐eye view

• 1. This study examines the perceptions of 500 Sri Lankan fishers about influences on the outcome of the 2004 Asian tsunami. It is based upon analysis of questionnaire data on 13 natural environmental and development risk factors, in relation to human deaths and house damage (impact indicators).
• 2. Mangroves, coral reefs and sand dunes afforded protection against tsunami damage (67–94% of fisher responses), as did housing and roads.
• 3. Fishers overall believed rivers/estuaries, concave coastlines and hotels exacerbated impacts. However, a significantly greater proportion of fishers living within 100 m of the coast reported that rivers/estuaries had a protective role than those living further inland. Rivers seemingly diverted ‘tsunami water’ far inland, where it overflowed and caused damage.
• 4. Risk and damage are multi‐faceted concepts and measurable in different ways. Findings are considered in the light of ecological studies and modelling, with special reference to mangroves, whose alleged protective role has become equivocal during post‐tsunami research.
• 5. Insights of fishers and other communities with intuitive knowledge add a valuable perspective to the understanding of natural disasters and environmental change. This approach is seen as complementary rather than an alternative approach to purely ‘scientific’ research.

Copyright © 2008 John Wiley & Sons, Ltd.