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Components of bedding might interact with experimental treatments and affect the outcome of various experiments. Here we studied the biochemical effects of 3 rodent bedding materials that are commonly used in Egypt. Male and female rats and mice were assigned randomly into 4 single-sex and single-species groups (10 animals per group). Three types of bedding-rice straw, wheat straw, and pine wood shavings-were evaluated. After 4 wk, animals were euthanized, and biochemical parameters were measured. In male and female rats given wood shavings, serum ALT activity and malondialdehyde concentration increased whereas catalase activity decreased compared with levels in the wheat straw group. In contrast, ALT activity and malondialdehyde concentrations decreased but CAT activity increased in rats housed on rice straw compared with wheat straw. Serum AST and ALT activities increased in male and female mice exposed to rice straw, whereas the malondialdehyde concentration increased and catalase decreased in the wood shavings group relative to the wheat straw group. In mice exposed to wheat straw, AST and ALT activities and malondialdehyde concentrations decreased and CAT activity increased compared with the other groups. Because our results showed that exposure to wood shavings affects some biochemical parameters of rats and mice, we do not recommend its use as laboratory animal bedding. We consider that, of the materials tested, rice straw bedding is the best bedding material for rats, whereas wheat straw is best for mice.

The present study aimed to investigate the potential role of leptin in the progression of breast cancer and the associated cell proliferation signalling pathway(s). A total of 44 female patients diagnosed with breast cancer and 24 healthy donors from Ain Shams University Hospitals (Cairo, Egypt) were enrolled in the present study. The present study assessed leptin expression in breast cancer tissues at the gene and protein level using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry. The results demonstrate that the expression of leptin was significantly higher in tissue of breast cancer samples from obese patients than overweight and control samples (P<0.001). ELISA results indicated a significant increase (P<0.001) of leptin expression in obese patients. To investigate whether there is any difference in leptin expression between the peripheral and tumor microenvironment blood of patients with breast cancer, the concentration of leptin was assessed in plasma from both using ELISA assays. The results demonstrated a statistically significant increase in the level of leptin in plasma samples from the tumor microenvironment of obese patients with estrogen receptor positive (ER+) breast cancer, compared with peripheral plasma samples. Furthermore, the leptin gene was overexpressed in obese ER+ breast cancer tissue. RT-qPCR was also performed to assess the expression of genes involved in proliferation pathways including leptin receptor (LEPR), aromatase, mitogen activated protein kinase (MAPK) and signal transducer and activator of transcription-3 (STAT3). A positive association between leptin expression, LEPR, aromatase, MAPK and STAT3 was detected in tissue samples of patients with breast cancer. The current study concluded that leptin may enhance breast cancer progression by inducing the expression of JAK/STAT3, ERK1/2 and estrogen pathways in obese patients breast cancer.

Purpose: The effects of chronic chloroquine administration on serum proteins and free amino acids of rabbits and the accompanying ultrastructural changes in the retina were investigated., Methods: Thirty pigmented rabbits were injected intramuscularly with chloroquine diphosphate (14 mg/Kg bw). Fifteen rabbits served as control. Blood samples drawn after 1, 2, 3, 4, 5, 6 and 12 months were assayed for serum proteins by Bio-analytic kits and horizontal electrophoretic technique. Free amino acids were determined by Beckman analyzer. Central retinal tissue was fixed in 4% glutaraldehyde, embedded in araldite CY212 and sectioned for ultrastructural examination., Results: Histopathologic changes were apparent within three months, initially affecting the pigment epithelium and photoreceptors and later involving the remaining neuroretinal layers. Hypoproteinemia gradually developed mainly due to a sharp drop in albumin and alpha 1 and 2 globulin fractions, inspite of an increase in beta and gamma globulin fractions. The concentration of non-essential amino acids varied considerably from a depletion of taurine, aspartine, glutamine, tryptophan and arginine to an increase of serine, alanine, GABA and ornithine. The most outstanding effect was the disappearance of tyrosine and its return to normal value at the end of the experiment., Conclusion: The disturbances in protein pattern and free amino acid levels are an indication of chloroquine toxicity and may be implicated in the retinopathy.