Cisplatin (CDDP) is one of the most active cytotoxic agents in the treatment of cancer and has adverse side effects such as nephrotoxicity and hepatotoxicity. The present study was designed to determine the effects of royal jelly (RJ) against oxidative stress caused by CDDP injury of the kidneys and liver, by measuring tissue biochemical and antioxidant parameters and investigating apoptosis immunohistochemically. Twenty-four Sprague Dawley rats were divided into four groups, group C: control group received 0.9% saline; group CDDP: injected i.p. with cisplatin (CDDP, 7 mg kg−1 body weight i.p., single dose); group RJ: treated for 15 consecutive days by gavage with RJ (300 mg/kg/day); group RJ + CDDP: treated by gavage with RJ 15 days following a single injection of CDDP. Malondialdehyde (MDA) and glutathione (GSH) levels, glutathione S-transferase (GST), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) activities were determined in liver and kidney homogenates, and the liver and kidney were also histologically examined. RJ elicited a significant protective effect towards liver and kidney by decreasing the level of lipid peroxidation (MDA), elevating the level of GSH, and increasing the activities of GST, GSH-Px, and SOD. In the immunohistochemical examinations were observed significantly enhanced apoptotic cell numbers and degenerative changes by cisplatin, but these histological changes were lower in the liver and kidney tissues of RJ + CDDP group. Besides, treatment with RJ lead to an increase in antiapoptotic activity hepatocytes and tubular epithelium. In conclusion, RJ may be used in combination with cisplatin in chemotherapy to improve cisplatin-induced oxidative stress parameters and apoptotic activity.

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Dictyostelids are free-living phagocytes that feed on bacteria in diverse habitats. When bacterial prey is in short supply or depleted, they undergo multicellular development culminating in the formation of dormant spores. In this work, we tested isolates representing four dictyostelid species from two genera (Dictyostelium and Polysphondylium) for the potential to feed on biofilms preformed on glass and polycarbonate surfaces. The abilities of dictyostelids were monitored for three hallmarks of activity: 1) spore germination on biofilms, 2) predation on biofilm enmeshed bacteria by phagocytic cells and 3) characteristic stages of multicellular development (streaming and fructification). We found that all dictyostelid isolates tested could feed on biofilm enmeshed bacteria produced by human and plant pathogens: Klebsiella oxytoca, Pseudomonas aeruginosa, Pseudomonas syringae, Erwinia amylovora 1189 (biofilm former) and E. amylovora 1189 Δams (biofilm deficient mutant). However, when dictyostelids were fed planktonic E. amylovora Δams the bacterial cells exhibited an increased susceptibility to predation by one of the two dictyostelid strains they were tested against. Taken together, the qualitative and quantitative data presented here suggest that dictyostelids have preferences in bacterial prey which affects their efficiency of feeding on bacterial biofilms.

Although there is a general consensus that housing conditions affect the well-being of laboratory animals, the ideal cage size and density for housing laboratory rodents has not been established. The authors investigated the effects of cage size and cage density on growth, organ development, metabolic profile, and hemogram in juvenile Sprague-Dawley rats. Larger cages and increased cage density were associated with depressions in body weight and in the weights of several organs. In general, increasing group size and density correlated more strongly with detrimental effects on the growth of females than males, although hemogram values indicated that males are more prone to emotional stress and immune suppression than females in response to increasing group size and crowding.

This experiment was conducted to examine the effects of cage type (CT) and cage density (CD) on physiological variables in growing rats. Sprague Dawley rats (n = 108) weighing an average of 46 g were housed in metallic cage with woodchip bedding (MCWB), metallic cage with wire mesh (MCWM), and plastic shoebox with woodchip bedding (PCWB) separately by sex at normal (160-cm 2 /rat, ND) and high (80-cm 2 /rat, HD) CD from 3 to 10 wks of age. All cages were in dimension of 24×40×20 cm (W×D×H). At the end of the experiment, blood samples were collected and 6 rats from each cage were sacrificed. No death was observed among rats at ND, whereas mortality rate at HD was 22.3% for males and 13.9% for females. Heart weight was affected by CT. Doubling CD caused 23, 11.8, 17.9, 8.6, 6.9, and 16.4% decreases in BW and weights of heart, liver, kidney, testis, and ovary, respectively. Except for adrenal gland, other organs for males were heavier than for females. Liver weight of males and females responded differently to CT and CD. Comparing with females, males had 7.3 and 5.2% heavier and 9.9% lighter liver weights in MCWB, MCWM, and PCWB, respectively. As CD doubled, liver weight for males and females decreased by 22.4 and 13.1%, respectively. Mean adrenal gland weight increased by 8.4% and decreased by 9.7% for males and females, respectively, with doubling CD. CT affected glucose, TG, Ca, and ALP levels. However, CD did not alter blood chemistry. Rats housed in metallic cages had greater neutrophil count and neutrophil:lymphocyte ratio than rats housed in plastic cages. Doubling CD caused a 24.2% increase in lymphocyte count. There were CT by CD, CT by sex, and CD by sex interaction effects on lymphocyte count. Doubling CD caused 0.1% decrease and 49.8 and 26.7% increases in lymphocyte count for rats housed in MCWB, MCWM, and PCWB, respectively. Comparing with females, lymphocyte count for males housed in MCWB, MCWM, and PCWB had 8.9 and 12.9% greater and 30.3% less lymphocyte counts, respectively. Lymphocyte count decreased by 4.12% for males, whereas it increased by 61.0% for females as CD doubled. Doubling CD resulted in 2.5 and 2.3% increases in erythrocyte count and hematocrit value. These data suggest that animals perform better in metallic cages than in plastic cages and that cage density had pronounceable effects on physiological parameters in a cage type and sex dependent-manner.