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In this study, BRL 3A cells were treated with different Cd concentrations (0, 10, 20, and 40 μmol/L) for 12 h and preincubated with or without N-acetyl-L-cysteine (NAC) (2 mmol/L) for 30 min, and cells were treated with Cd (0 and 20 μmol/L), pretreated with p38 inhibitor (SB203580), JNK (c-Jun NH2-terminal kinases) inhibitor (SP600125), and extracellular signal-regulated kinase (ERK) inhibitor (U0126) for 30 min, and then treated with 20 μmol/L Cd for 12 h. Cd decreased cell viability, SOD, and GSH-Px activity in a concentration-dependent manner. Increased MDA level, ROS generation, nuclear condensation, shrinkage, and fragmentation in cell morphology were inhibited by NAC. Cd-induced apoptosis was attenuated by pretreatment with SB203580, SP600125, and U0126. The results of western blot showed that NAC preincubation affected Cd-activated MAPK pathways, p38 and ERK phosphorylation. Cd treatment elevated the mRNA levels of Bax and decreased the mRNA levels of Bcl-2, respectively. The same effect was found in their protein expression levels. These results suggest that oxidative stress and MAPK pathways participate in Cd-induced apoptosis and that the balance between pro- and antiapoptotic genes (Bax and Bcl-2) is important in Cd-induced apoptosis.

Epidemiological studies have indicated incidences of 32.9% and 27.8% for rickets and osteomalacia, respectively, in Bactrian camels (Camelus bactrianus), but there is an increased incidence under drought conditions, sometimes reaching 75%. We have found that concentrations of phosphorus and copper in forage and soil samples in a drought affected area were significantly lower than in a control area or normal reference values (P < 0.01) ; the mean Ca:P ratio in the forages was 50:1. The phosphorus content of blood and hair from affected camels was significantly less than that in controls (P < 0.01) and concentrations of copper in the liver and kidney were significantly lower in affected camels than control animals (P < 0.01); the concentrations of triiodothyronine (T(3)), thyroxine (T(4)) and parathyroid hormone (PTH) in the serum from affected animals were significantly higher than those from healthy controls (P < 0.01); serum inorganic phosphorus and ceruloplasmin levels were lower than those in the controls (P < 0.01 or P < 0.05); the concentrations of serum alpha-globulin and beta-globulin were significantly higher in the affected camels than in the healthy controls (P < 0.01). The pathological changes seen in camels affected with rickets included porous, brittle, light, osteoporotic bones that were susceptible to fractures and had less resistance to cutting and sawing. Wrist joints were enlarged with an apparent bowing of the long bones in forelimb and with typical broadening of the epiphyses. In adult female camels, many enlarged scars were often seen in ribs indicating earlier fractures. The disease could be cured with supplementary bone meal, phosphate or mineral mixtures and in field investigations clinical signs disappeared within 15 days. Over the same period, the concentrations of phosphorus and alkaline phosphatase in blood returned to normal. The disease may be effectively prevented by use of mineral blocks (block salt licks) or dosing orally with copper, selenium and cobalt soluble glass boluses. We conclude that rickets and osteomalacia are mainly caused by phosphorus and copper deficiencies in the pasture.

Reference values were established for some haematological and serum biochemical constituents in Bactrian camels (Camelus bactrianus) in China. The contents of seven trace elements in the blood, hair, liver, kidney, heart, spleen, lung, cerebrum, cerebellum, rib, ovary, pancreas and gluteal muscle of Bactrian camels were also measured. Some of these values are reported for the first time for Bactrian camels in China. Most haematological and serum biochemical values were similar to those of cattle, yaks, sheep and dromedary camels, but the mean serum albumin concentration and the albumim/globulin ratio were significantly higher than those in other ruminants and the mean thyroxine concentration was half that in dromedary camels. The liver contained the highest concentrations of copper, zinc, manganese and iron, and the renal cortex contained the highest concentration of selenium. The concentrations of selenium, cobalt, zinc, manganese and molybdenum in the tissues were within the reference ranges for other ruminants, but the mean iron and copper concentrations in the liver were significantly higher than those in other ruminants.