Yavuz Kursad Das

Subacute oral toxicity of combinations of selected synthetic pyrethroids, piperonyl butoxide, and tetramethrin in rats

In this study, 70 Wistar rats were randomly divided into seven equal groups (six experimental and one control), which consisted of animals belonging to both sexes. Different combinations of insecticides were administered daily to the experimental groups (group 1: cypermethrin + piperonyl butoxide (PBO); group 2: alphacypermethrin + PBO; group 3: deltamethrin + PBO; group 4: cypermethrin + PBO + tetramethrin; group 5: alphacypermethrin + PBO + tetramethrin; and group 6: deltamethrin + PBO + tetramethrin) for 28 days. During the study period, mortality and serious clinical findings were not observed in any animal. However, feed consumptions decreased in groups 1 and 3 (p < 0.05). Red blood cells, white blood cells, and hemoglobin levels, especially in cypermethrin and alphacypermethrin groups (groups 1, 2, and 4), were found to be higher than the control group (p < 0.05). Furthermore, biochemical changes related to liver, kidney functions, and protein metabolism occurred in males of almost all the groups. Relative liver and kidney weights of the male animals increased in the cypermethrin and alphacypermethrin groups (p < 0.05). The most common finding observed during the histopathological examination of all the experimental groups was centrilobular degeneration in the liver. It was concluded that although clinical symptoms were not observed, synthetic pyrethroid, synergist, and knockdown agent combinations might cause serious abnormalities when administered in certain doses in mammalians.

Repeated-dose 14-day dermal toxicity of different combinations of some synthetic pyrethroid insecticides, piperonyl butoxide, and tetramethrin in rats

The aim of this study was to evaluate the repeated-dose 14-day dermal toxicity of different combinations of some synthetic pyrethroid insecticides, piperonyl butoxide, and tetramethrin in rats. A total of 70 adult Wistar rats were randomly divided into 7 (6 experimental and 1 control) groups. Different combinations of insecticides were dermally applied to the rats in the experimental groups for 14 days. Clinical observations were performed daily; hematologic and biochemical parameters were also determined. Gross necropsy and histopathologic examinations were performed systematically, and organ weights were recorded. Although the administered doses of the insecticides were relatively lower than their acute dermal toxicity values, a high mortality rate (27 of 60 experimental animals, 45%) was observed. Furthermore, the insecticide combinations caused decreased body weights and feed consumptions, increased organ weights, and hematologic, biochemical, and common histopathologic changes. As a result, the findings showed that although pyrethroids are considered to be of low acute toxicity, they become more toxic when combined with piperonyl butoxide or tetramethrin in certain doses.

Telbivudine attenuates gentamicin-induced kidney injury in rats

Nephrotoxicity has been associated with nucleos(t)ide analogues other than telbivudine (LdT). This study investigated the potential effects of LdT and lamivudine (LAM) on renal function in an experimental rat model of gentamicin-induced acute nephrotoxicity. A total of 28 healthy Wistar albino rats were randomly divided into four experimental groups: negative control; positive control (PC); LdT; and LAM. Nephrotoxicity was induced by gentamicin in the LdT, LAM and PC groups. LdT and LAM were administered to two groups for 6 weeks starting on the ninth day. Blood samples were collected weekly and cystatin C levels were measured by ELISA. Animals were sacrificed on the 50th day and the kidneys were removed for histological examination. Serum cystatin C levels differed significantly between the LdT and LAM groups (P <0.007) and between the LdT and PC groups (P <0.001). Renal function was significantly improved in the LdT group at the start of antiviral treatment on Day 8 and at the end of treatment on Day 50 (P = 0.001 and 0.007). Glomerular injury, acute tubular necrosis and total injury score were significantly reduced in the LdT group relative to the PC and LAM groups upon histopathological examination. LdT was associated with significant improvements in renal function as measured by biochemical and histopathological methods. The acute kidney injury model data should be supported by clinical studies to suggest that LdT treatment may have advantages for patients with underlying chronic kidney disease receiving chronic hepatitis B treatment.

Determination of plasma concentrations of organochlorine pesticides and polychlorinated biphenyls in pet cats and dogs

The aim of this study was the determination of plasma concentrations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in cats and dogs and evaluation of their prevalence and possible effects. The concentrations of nine OCPs, such as α-hexachlorocyclohexane (HCH), β-HCH, γ-HCH, hexachlorobenzene (HCB), aldrin, 2,4′-dichlorodiphenyltrichloroethane (2,4′-DDT), 4,4′-DDT, 2,4′-dichlorodiphenyldichloroethylene (2,4′-DDE) and 4,4′-DDE and 16 PCBs (PCB-28, -52, -70, -74, -81, -99, -101, -118, -138, -153, -156, -170, -180, -183, -187 and -208) were evaluated in the plasma samples of pet cats (n = 15) and dogs (n = 21). The concentrations of OCPs ranged from 1.12 ng g−1 lipid weight (lw) to 7.65 ng g−1 lw in cats and from 1.25 ng g−1 lw to 6.79 ng g−1 lw in dogs. In addition, mean PCB levels were 0.58–5.66 and 0.52–6.62 ng g−1 lw in cats and dogs, respectively. β-HCH, γ-HCH and PCB-138 levels were significantly higher in dogs (p < 0.05). As far as could be determined, OCPs and PCBs were detected in the plasma samples of domestic cats and dogs in Turkey for the first time. Their concentrations were similar to those reported in earlier studies abroad. However, in contrast to other research, the levels of some OCPs were higher in dogs than in cats. It is concluded that, because of their high prevalence and potential health effects in animals and humans, OCP and PCB levels should be monitored systematically in domestic cats and dogs.