Effect of adrenalectomy and hydrocortisone on ventral prostate of rats

Aim: To study the effects of adrenalectomy and hydrocortisone on the ventral prostate of SD rats. Methods: Inadrenalectomised (ADX) and ADX + hydrocortisone (1, 2, or 4 mg) treated rats, the prostatic histology and thecholesterol, protein, zinc, and copper levels and the enzymic profile (acid phosphatase, alkaline phosphatase, aryl sul-phatase, lactic dehydrogenase, and leucine aminopeptidase) in the prostatic tissue were determined; the serum hormon-al profile (testosterone, FSH and LH) was also assayed. Results; Adrenalectomy caused a progressive degenerationin prostatic structure that was not reversed by hydrocortisone treatment. The serum testosterone were significantly lowerin ADX than in sham operated rats and lower in ADX + hydrocortisone than in ADX-C rats (P < 0.01). The serumFSH and LH were below the detection limit of 1 mIU/mL. The enzymatic activity was higher in ADX than in sham op-erated rats and higher in ADX + hydrocortisone than in ADX-C rats (P<0.05-0.01). The prostatic zinc levels weresignificantly higher in sham operated than in ADX, and higher in ADX-C than in ADX + hydrocortisone rats (P < 0.05-0.01). The prostatic copper level was significantly lower in sham operated than in ADX, and lower in ADX-C thanin the ADX + hydrocortisone rats (P <0.01). Conclusion; In rats, adrenalectomy leads to pathological and func-tional changes of the prostate. Hydrocortisone treatment at the doses employed did not reverse these changes. (Asian JAndrol 2001 Dec; 3: 289 - 300)

Long-term effects of environmentally relevant concentrations of silver nanoparticles on microbial biomass, enzyme activity,and functional genes involved in the nitrogen cycle of loamy soil

The increasing production and use of engineered silver nanoparticles（AgNP） in industry and private households are leading to increased concentrations of AgNP in the environment. An ecological risk assessment of AgNP is needed, but it requires understanding the long term effects of environmentally relevant concentrations of AgNP on the soil microbiome. Hence, the aim of this study was to reveal the long-term effects of AgNP on soil microorganisms. The study was conducted as a laboratory incubation experiment over a period of one year using a loamy soil and AgNP concentrations ranging from 0.01 to 1 mg AgNP/kg soil. The short term effects of AgNP were, in general, limited.However, after one year of exposure to 0.01 mg AgNP/kg, there were significant negative effects on soil microbial biomass（quantified by extractable DNA; p = 0.000） and bacterial ammonia oxidizers（quantified by amo A gene copy numbers; p = 0.009）. Furthermore, the tested AgNP concentrations significantly decreased the soil microbial biomass, the leucine aminopeptidase activity（quantified by substrate turnover; p = 0.014）, and the abundance of nitrogen fixing microorganisms（quantified by nif H gene copy numbers; p = 0.001）. The results of the positive control with Ag NO3 revealed predominantly stronger effects due to Ag＋ion release. Thus, the increasing toxicity of AgNP during the test period may reflect the long-term release of Ag^＋ions. Nevertheless, even very low concentrations of AgNP caused disadvantages for the microbial soil community, especially for nitrogen cycling, and our results confirmed the risks of releasing AgNP into the environment.