[Long-term effect of environmental cadmium exposure on human body's mineral metabolic balance].

OBJECTIVE: To investigate the effect of long-term exposure to environmental cadmium on eight mineral element's metabolic balance of human body. METHODS: To choose a high cadmium area polluted by smelting and mining north of Guangdong province and a cadmium-free area with a similar economic level, and living and eating habit of residents as a contrast from April 2011 to August 2012. Stratified random sampling and clustered sampling method were adopted to choose the non-occupationally cadmium-exposed respondents who have lived in local area for more than 15 years, older than 40 years, having local rice and vegetable as the main dietary source, with simple and relatively stable diet, and without diabetes, kidney disease, thyroid disease, liver disease or other history of chronic disease. This study included 298 respondents, of whom 155 were in cadmium exposure group and 143 in control group. Questionnaires was used to acquire their health status and their morning urine samples were collected. Electrolytically coupled plasma mass spectrometry (ICP-MS) was used to test the concentrations of sodium(Na), magnesium (Mg), phosphorus (P), potassium (K), calcium (Ca), copper (Cu), zinc (Zn) and iodine (I). The Mann-Whitney U test method was used to compare the differences of concentrations of urinary cadmium, Na, Mg, P, K, Ca, Cu, Zn, I, and the ratio of Na to K (Na/K), Ca to P (Ca/P) between exposed group and control group.χ(2) test was used to compare the abnormal rate of urinary cadmium between exposed group and control group. Pearson correlation and multiple regression method were used to investigate the relationship between urinary cadmium levels, gender, age, smoking, passive smoking, and minerals. RESULTS: The urinary cadmium level P50 (P25-P75) in exposed group was 5.45 (2.62-10.68) µg/g·cr, which was higher than that of the control group, which was 1.69 (1.22-2.36) µg/g·cr (Z=-10.49,P<0.001). The abnormal rate of urinary cadmium was 51.6% (80/155), which was higher than that of the control group (2.8 %(4/143)) (χ(2)= 87.56, P<0.001). The urinary Ca, Cu, Zn, and I level P50 (P25-P75) of exposed group were 173.80 (114.40-251.70), 20.55 (14.95-28.44), 520.23 (390.25-647.15), and 246.94 (203.65-342.97) µg/g·cr, which were higher than those in control group (142.42 (96.87-179.11), 15.44 (12.26-20.98), 430.09 (309.85-568.78) and 213.85 (156.70-281.63) µg/g·cr, respectively) (Z values were-4.33,-5.04,-3.47 and-4.24, all P values <0.001). The urinary P, K level P50 (P25-P75) of exposed group were 582.50 (463.20-742.8), 890.10(666.00-1 305.40) µg/g·cr, which were lower than control group (694.50 (546.20-851.17), 1 098.58(904.53-1 479.18) µg/g·cr) (Z values were-3.36,-4.02, all P values <0.001). on Based the results of Pearson correlation analysis, urinary cadmium was positively correlated with urinary Ca, Cu, Zn, and I, and the correlation coefficients were 0.31, 0.61, 0.38, and 0.25, respectively (all P values <0.05). Based on the results of multiple regression analysis, urinary cadmium levels contributed most to the metabolic balance of urinary Ca, Cu, Zn and I. The standardized regression coefficients were 0.31, 0.59, 0.39, and 0.24, respectively (all P values<0.001). CONCLUSION: Long-term environmental exposure to cadmium affected the metabolic balance of Ca, Cu, Zn and I in human body.

[Cadmium burden and renal dysfunction among residents in cadmium-polluted areas: A 3-year follow-up study].

OBJECTIVE: To investigate dynamic change of cadmium body burden and renal dysfunction among residents living in cadmium-polluted areas. METHODS: From April to July of 2011, the cadmium-polluted areas of northern Guangdong province in China was chosen as the study site. Based on the levels of cadmium pollution in soil and rice, the survey areas were divided into low exposed group (average concentration of cadmium was 0.15-0.40 mg/kg, 0.5-1.0 mg/kg in rice and soil, respectively) and high exposed group (average concentration of cadmium was >0.40 mg/kg, >1.0 mg/kg in rice and soil, respectively). Stratified random sampling and cluster sampling method of epidemiological investigations were carried out among 414 local residents who lived in cadmium exposure areas for more than 15 years, aged above 40, and without occupational cadmium exposure, including 168 and 246 residents in low and high exposed group, respectively. From March to June of 2014, 305 respondents of those who participated in 2011 were successfully traced, including 116 and 189 respondents in low and high exposed group, respectively. We used health questionnaires to acquire their health status. Home-harvested rice and vegetable samples were collected using quartering method for detection of cadmium level, including 190 rice samples, 161 vegetable samples in 2011 and 190 rice samples, 153 vegetable samples in 2014. Urine specimens of residents were collected for the detection of urinary cadmium and creatinine as well as renal dysfunction biomarkers, namely, N-acetyl-beta-D-glucosamidase (NAG) and ß2-microglobulin (ß2-MG), respectively. In 2011 and 2014, Chi-square test was used to investigate the differences of abnormality of cadmium concentration in rice, vegetables and urinary cadmium, ß2-MG, and NAG that were expressed as odds ratio(OR) and 95% confidence intervals (95%CI). RESULTS: In 2011 and 2014, cadmium concentration P50 (P25-P75) in rice was 0.43 (0.17-1.10) mg/kg, and 0.42 (0.20-1.14) mg/kg, respectively (Z=-0.77,P=0.440). In 2011 and 2014, cadmium concentrations P50 (P25-P75) in vegetables were 0.13 (0.07-0.34) mg/kg, and 0.25(0.12-0.59) mg/kg, respectively, with abnormal rates of 38.5%(62/161) and 60.8%(93/153), respectively. In 2014, both average concentration and abnormal rate of cadmium in vegetables were higher than those in 2011 (Z=-4.69, P<0.001 and χ(2)=15.58,P<0.001). Concentrations of urinary cadmium P50 (P25-P75) in high exposed group were 7.90 (3.96-14.91) µg/g creatinine, 8.64 (4.56-17.60) µg/g creatinine in 2011 and 2014, respectively. Contrary to that in 2011, urinary cadmium of high exposed group was significantly increased in 2014 (Z=-2.80, P=0.005). In 2011 and 2014, concentrations of ß2-MG, NAG P50 (P25-P75) were 0.15(0.07-0.29) µg/g creatinine, 0.15 (0.07-0.45) µg/g creatinine, and 7.12 (5.05-10.65) U/g creatinine, 13.55(9.1-19.84) U/g creatinine, respectively, with abnormal rates of 7.5% (23/305), 15.1% (46/305), 8.2% (25/305) , and 33.8% (103/305), respectively. Compared with baseline in 2011, average concentrations of ß2-MG, NAG significantly increased in 2014 (Z=-2.263, P=0.024 and Z=-12.52, P<0.001), and abnormal rates of ß2-MG, NAG were also higher in 2014 (χ(2)=15.61 , P<0.001 and χ(2)=64.72, P<0.001), with odds ratio(OR) of 2.00 (95%CI:1.23-3.24) and 4.12 (95%CI:2.87-5.92). CONCLUSION: Environmental cadmium pollution of crops such as rice and vegetables in survey areas continued to remain high. Body burden of cadmium might kept at sustainably high levels and renal dysfunction was worsened after continuous, long-term cadmium exposure. Our results suggested that NAG might be more sensitive than ß2-MG to serve as an indicator for an individual's future tubular function.

Total knee replacement subsequent to severe necrotising fasciitis of the lower limb.

The incidence of wound related complication following total knee arthroplasty is as high as 10%-20%. To perform total knee arthroplasty in a knee with extensive scarring around the knee can be a challenging task. We report a case of 55-year-old diabetic woman, who had total knee arthroplasty, performed two years after she had recovered from necrotizing fasciitis around the right knee. Understanding the vascular anatomy around the knee is of paramount importance in the planning of skin incision to ensure fewer wound related complications.

Locking compression plate: a treatment option for diaphyseal nonunion of radius or ulna.

Treatment of radius or ulna nonunion requires both osteogenic environment and mechanical stability. We would like to report three radial and six ulnar diaphyseal nonunions treated with 3.5 mm locking compression plate (LCP) fixation. To assess the effectiveness of 3.5 mm LCP in treating diaphyseal nonunion of the forearm bones, we prospectively reviewed nine patients with the mean age of 33 years with diaphyseal nonunion of the radius or ulna. All patients were treated with 3.5 mm LCP. Bone grafting was only performed for atrophic nonunion. Surgical and functional outcome were evaluated. There were three atrophic nonunion of the radius, four atrophic nonunion of the ulna and two hypertrophic nonunion of the ulna. All nonunion united successfully with satisfactory functional outcome. 3.5 mm LCP is effective in the treatment of nonunion of ulna or radius.