Pharmacokinetics of amoxycillin and the rate of depletion of its residues in pigs.

Six pigs were used in a two-period crossover study to investigate the pharmacokinetics of amoxycillin after single intravenous and oral doses of 20 mg/kg bodyweight. Twelve pigs were used to study the residues of the drug in muscle, kidney, liver and fat after they had received daily oral doses of 20 mg/kg amoxycillin for five days. The mean (sd) elimination half life (t1/2beta) and mean residence time of amoxycillin in plasma were 3.38 (0.30) and 3.54 (0.43) hours, respectively, after intravenous administration and 4.13 (0.50) and 4.47 (0.30) hours, respectively, after oral administration. After oral administration, the maximum plasma concentration (Cmax) was 7.37 (0.42) microg/ml and it was reached after 0.97 (0.29) hours. Six days after the last oral dose, the mean concentration of amoxycillin in the pigs' kidneys was 21.38 ng/g and in the liver it was 12.32 ng/g, but no amoxycillin could be detected in fat or muscle; the concentrations of amoxycillin in edible tissues were less than the European Union maximal residue limit of 50 microg/kg.

Effect of single and double strap backpacks on lung function.

Carrying heavy and moderate military loads in backpacks or as body armour compresses the chest, causing a change in lung function that is typical of a restrictive ventilatory impairment. It is not known if a lighter backpack load of only 6 kg, such as is typical of loads carried by students, will have a similar effect on lung function. There have been no studies examining whether backpacks of different strapping styles have an effect on lung function. Several designs of student backpack have recently been introduced to the market. One of the most popular is a single-strap backpack. This study examined Forced Vital Capacity (FVC), Forced Expiratory Volume in one second (FEV1), FEV1.FVC( - 1)% and Peak Expiratory Flow (PEF) in 13 participants (4 males, 9 females) wearing each of two 6 kg backpacks, one with two shoulder straps (a Double Strap Backpack (DSB)) and the other with a single strap (a Single Strap Backpack (SSB)) worn across the shoulder and chest. In comparison with the control of no pack (N), SSB significantly reduced FVC (by 3.94%, p = 0.006) but there were no significant differences in FEV1, FEV1. FVC( - 1)% and PEF. The DSB also significantly reduced FVC (by 1.97%, p = 0.034) but no significant differences were found in FEV1, FEV1. FVC( - 1)% and PEF measures. In comparison with DSB, the SSB was associated with a significantly lower FVC (by 2.05%, p = 0.049) and FEV1 (by 1.88%, p = 0.029) but there were no significant changes in FEV1. FVC( - 1)% and PEF. It is concluded that a backpack load of 6 kg could produce a mild restrictive type of ventilatory impairment in lung function. This effect was greater for a single cross-chest strap than for a more conventional double strap harness.