Cason Z

Prostatic Tissue Manipulation By Continous Delivery Of Estrogen/Dihydrotestoterone Uisng Ceramic Drug Delivery System

Tricalcium phosphate lysine drug delivery system (TCPL) has been used successfully to deliver various organic compounds at a sustained manner for long duration. Several studies conducted in our laboratories have used TCPL to treat various pathological disturbances. The objective of this study was to evaluate the effect of estrogen (E) and Dihydrotestosterone (DHT) delivered in a sustained manner by means of tricalcium phosphate-lysine (TCPL) delivery system on the morphological changes of ventral prostatic tissue. Adult male rats (BW 300350 gm, n = 24) were randomly divided into four equal groups: group I were implanted subcutaneously with TCPL loaded with estrogen (10 pq/ml), group I1 were implanted with TCPL loaded with DHT (2 ng/ml), group I11 were implanted with sham TCPL capsules and rats in group IV served as intact unimplanted controls. Surgical aseptic techniques were performed according to standard laboratory procedures. The animals were maintained at the University of Mississippi Medical Center Animal Facilities following the rules and regulations established by NIH on the Care and Use of Laboratory Animals. At the end of 8 weeks post implantation, all animals were sacrificed and the prostate tissues were collected, weighed and embedded for histopathological evaluations. Statistical analysis was conducted by using standard computer programs (STATVIEW). Data collected from this study have shown that exogenous intake of estrogen and DHT delivered in a sustained manner for eight weeks induced several pathophysiological conditions in ventral prostatic tissue in comparison to prostatic tissue collected from sham and control animals. Light microscopic evaluation of cross sections obtained from animals implanted with estrogen loaded TCPL revealed an atrophic pattem in the epithelium with loss of the cellular structure. In addition, 1 other observations such as low cuboidal and thin glands, pleomorphism, severe angiogenesis, presence of abundant connective tissue stroma and granulomatous conditions were detected. In contrast, cross section of ventral prostate tissue collected from animals implanted with TCPL filled with DHT (Group 11) revealed the following: (i) pleomorphism, (ii) occasional presence of connective tissue stroma, (iii) prostatic hypertrophy alone, or in conjunction with hyperplasia of the ,epithelial cell and (iv) involvement of inflammatory cells. In conclusion, the results of this study suggest that the use of TCPL capsules loaded with estrogen and androgens can be used effectively to regulate the growth of prostatic tissue.

Detection of nonspecific immunohistochemical response caused by tissue necrosis and the presence of metallic wear debris

Tissues retrieved during revision arthroplasty (n=25) were processed for routine immunohistochemical techniques to localize the presence of bone resorbing cytokines (IL-1 and IL-6), and to identify areas of significant necrosis and metallic deposition. Tissues were processed and embedded according to standard laboratory techniques. Several slides were prepared for each tissue sample taken. Several sequential slides were stained for Hematoxylin and Eosin to demonstrate cell type. Other slides of the same tissues were processed for localization of cytokines, IL-1 and IL-6. To identify specific cytokine reactions, the tissues were first blocked with proteins to ensure that all. The results revealed that there were several locations on the tissues that appeared highly reactive for cytokines IL-1 and IL-6. However, some of these areas turned out to be nonspecific when compared with negative controls and the Hematoxylin and Eosin stained slides. Areas of extreme necrosis or where metal debris was presence demonstrated sites of nonspecific reactivity. Areas of necrosis have a high nonspecific affinity for antibodies and these areas of necrosis can be demonstrated on the Hematoxylin and Eosin sections, and should be avoided in determining the amount of specific cellular reactivity. In addition, new immunohistochemical techniques use cobalt ions as enhancers of peroxidase response, in areas on slides labeled as negative controls where metallic debris was trapped, there was an increase in nonspecific positive reactivity. These factors must be carefully controlled in determining true cellular responses that causes resorption of bone and implant failure.