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It has been well documented that human milk contains several immunomodulator components which are important during infant period when the newborn's immune system is still under development. In this study, we aim at examining levels of cytokines, zinc (Zn), and copper (Cu) in milk from mothers of premature and mature infants, and comparing changes during lactation periods consequently. Milk was collected from total of 40 mothers (group M: mothers of mature infants, n = 20; group PM: mothers of premature infants, n = 20) from four lactation stages: colostrum (0–7 days), transitional (7–14 days), mature milk (21 days), and mature milk (2nd month). Levels of cytokines (interleukin [IL]-lβ, IL-2, IL-6, IL-8, tumor necrosis factor-alpha [TNF-α]) were determined by chemiluminesence method, whereas atomic absorption spectrophotometer was used for the determination of Zn and Cu levels. Cytokine levels were determined to be high in colostrum and transient milk from mothers of full-term infants, whereas their levels were reduced drastically in the 21st day and the 2nd month milk (P < .01 , P < .001). Similar trends were observed in milk from mothers of premature infants, but cytokine levels were significantly lower in colostrum compared to colostrum from mothers of mature infants (P < .01). The differences in cytokine levels were continuous in transient milk (P < .05) and mature milk (21 days) (P < .05), whereas there was no statistically significant differences between milk from both groups of mothers in the 2nd month (P > .05). Zn levels in milk from mothers of premature infants were significantly lower compared to the ones from mothers of mature infants (P < .01) and these differences continued through the 2nd month. Although Cu levels were lower in milk from mothers of premature infants, there was no statistically significant difference except colostrum (P > .05). Our results clearly demonstrate that the level of immunomodulating agents such as cytokines and trace elements in milk from mothers of premature infants is less than the level of the same agents in milk from mothers of full-term infants. Although there are commercially available products for infant feeding, human milk is still the best natural nutrient for newborns. Therefore, when premature infants are breastfed, necessary precautions such as supplemantary diets must be considered for possible infections and risks related with immune system deficiency.

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Paint thinner is a commonly used industrial solvent with considerable potential for abuse by inhalation. Paint thinner is taken into the body by inhalation or by contact with the skin. Paint thinner is oxidized gradually by cytochrome P450-dependent monooxygenase and consequently free radicals are produced. In the present study we measured plasma malondialdehyde (MDA, a product of lipid peroxidation) levels as an indicator of oxidative damage and activity levels of antioxidant enzymes gluthatione peroxidase (GSH-Px) and superoxide dismutase (SOD) in erythrocytes of a group of people (n = 18) working with paint thinner. The control group was composed of 18 healthy adults. There was a statistically significant (p < 0.001) increase in MDA (2.0+/-0.7 nmol ml(-1)) and GSH-Px (86.5+/-16.6 U g(-1) Hb) activity levels in people working with paint thinner compared with control subjects (MDA: 1.0+/-0.3 nmol ml(-1); GSH-Px: 53.9+/-14.5 U g(-1) Hb). Similarly, there was also an increase (p < 0.05) in the SOD levels (1079+/-214.6 U g(-1) Hb) of people working with paint thinner compared with controls (953.3+/-46.7 U g(-1) Hb). Based on our results, it can be concluded that paint thinner inhalation may increase lipid peroxidation and consequently induce antioxidant enzymes.

Functional irregularities due to damage after ischaemia-reperfusion vary depending upon the organs affected. High energy phosphates such as ATP and ADP are destroyed after ischaemia-reperfusion damage. Subsequently, protons and inorganic phosphates accumulate within the cells and the proton pumps such as adenosine triphosphatase (ATPase), which maintain intracellular ion balance are damaged. In the present study, malondialdehyde (MDA), a product of lipid peroxidation, was measured as an indicator of tissue damage. Additionally, we measured sodium-potassium-ATPase levels and determined the interactions between MDA and Na+-K+ ATPase levels. A total of 31 female guinea pigs were divided into four groups: sham operated guinea pigs (group 1), ischaemia-reperfusion (group 2), ischaemia-reperfusion + superoxide dismutase (SOD) (group 3), ischaemia-reperfusion + allopurinol (group 4). Following reperfusion, the livers of guinea pigs in each group were removed for histopathological examination and the levels of MDA and Na+-K+ ATPase were determined in homogenized tissue samples. There was a statistically significant (p < 0.05) reduction in tissue MDA levels in group 2 when compared with group 1. The level of tissue MDA in groups 3 and 4 was significantly lower than tissue MDA levels of group 2. However, there was a statistically significant (p < 0.05) reduction in tissue Na+-K+ ATPase levels of group 2 when compared with group 1. Similarly, the level of tissue Na+-K+ ATPase in groups 3 and 4 was significantly higher than the tissue Na+-K+ ATPase levels of group 2. The results of the histopathologic examination also revealed the beneficial effects of the use of SOD and allopurinol in preventing liver damage in cases of ischaemia-reperfusion. Although the levels of MDA and Na+-K+ ATP ase in group 2 were not equal to the level in group 1, antioxidant therapy significantly improved the tendency to reverse the effects of ischaemia-reperfusion and to protect the liver from damage due to ischaemia-reperfusion.