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Tissue Collection (tissue + collection)
Selected AbstractsChanges in Preoptic and Hypothalamic Levels of Progesterone Receptor mRNA Across the Oestrous Cycle of the EweJOURNAL OF NEUROENDOCRINOLOGY, Issue 5 2001C. J. Scott Abstract We measured the levels of progesterone receptor (PR) mRNA in the hypothalamus and preoptic area (POA) of the ewe across the oestrous cycle. Perfusion-fixed hypothalamic tissue was collected from sheep killed during the luteal and follicular phases and during behavioural oestrus. Blood samples taken at the time of tissue collection verified that the oestrous ewes were undergoing a preovulatory luteinizing hormone (LH) surge. Matched sections were taken from the POA, periventricular nucleus (PeVN), ventromedial nucleus (VMN) and arcuate nucleus of each animal. In situ hybridization was performed using a sheep specific, 35S-labelled riboprobe for PR and semiquantitative image analysis was conducted on emulsion-dipped slides. The number of silver grains per cell was greater in the VMN and arcuate nucleus of oestrous ewes than in luteal and follicular phase ewes; there was no cyclic variation in the level of PR mRNA expression in the cells of the POA and PeVN. The number of labelled cells per mm2 in the VMN was higher in the oestrous ewes than in luteal phase and follicular phase ewes. The number of labelled cells in the PeVN was also higher in the oestrous ewes than in follicular phase ewes, but there was no cyclic variation in the POA and arcuate nucleus. In the ewe, the onset of behavioural oestrus corresponds to the onset of the preovulatory LH surge and increased PR mRNA expression at this time is likely to be due to the high concentrations of circulating oestrogen that precede this period. [source] An evaluation of PCR primer sets used for detection of Propionibacterium acnes in prostate tissue samplesTHE PROSTATE, Issue 14 2008Karen S. Sfanos Abstract BACKGROUND Multiple studies have now shown that Propionibacterium acnes can be cultured from post-prostatectomy derived prostate tissue samples. In contrast, both universal eubacterial 16S rDNA PCR and P. acnes -specific 16S rDNA PCR have failed to detect this organism at a frequency similar to that of bacterial culture. A potential explanation for this discrepancy, proposed by Cohen et al., involves mismatches in 16S rDNA primer sets used for bacterial detection. METHODS The sensitivity of both a previously published P. acnes -specific primer set containing a potential mismatch and a new primer set with no mismatches was determined. Both primer sets were used to interrogate two sets of DNA samples derived from post-prostatectomy prostate tissues that differed in the level of sterile precautions maintained during tissue collection. RESULTS The number of P. acnes positive samples was associated with the sterility of the sample collection process. In all instances, positive samples were determined to reflect low cell numbers (<10 CFU). CONCLUSIONS Although the results of previous studies have shown that P. acnes is not the only organism potentially present in the prostates of prostate cancer patients, mismatches in PCR primer sets may have also influenced the sensitivity of P. acnes detection. When using PCR in determining the presence of P. acnes in the human prostate, care should be taken to establish the potential influence of exogenous contamination and, due to the sensitivity of the assay, samples exposed to the urethra during the collection process (prostatic secretions, TURP specimens) should not be used. Prostate 68: 1492,1495, 2008. © 2008 Wiley-Liss, Inc. [source] The ethics of reusing archived tissue for researchNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 5 2000R. Ashcroft Pathologists have been establishing archives of human organs and tissue for research use for many years now. Controversy has arisen recently over these collections, particularly with regard to the right of patients or relatives to consent to removal and retention of tissue, genetic research using stored tissue samples, and commercial exploitation of tissue collections and genetic material. This paper discusses the ethics of reusing existing archives of tissue. New archives are established under much more stringent conditions than in the past. What rules should apply to existing archives? Guidelines to regulate such use are useful, but face serious difficulties in balancing the variety of public and private interests relating to tissue banking. Consent cannot be obtained retrospectively, but public trust can be established by open acknowledgement of the evolution of ethical standards and strict adherence to current best practice. Guidelines and standards vary from country to country, but ethical principles should not. The implications of this view for pathologists worldwide are discussed. [source] Apoptosis regulators Fau and Bcl-G are down-regulated in prostate cancerTHE PROSTATE, Issue 14 2010Mark R. Pickard Abstract BACKGROUND The molecular control of cell death through apoptosis is compromised in prostate cancer cells, resulting in inappropriate cell survival and resistance to cytotoxic therapy. Reduced expression of the functionally connected apoptosis-regulators and candidate tumor suppressors Fau and Bcl-G has recently been implicated in oncogenesis in other tissues. The present study examines the hypothesis that reduced expression of these genes may be involved in prostate cancer. METHODS Fau and Bcl-G mRNA levels were determined by real time RT-PCR in two independent prostate tissue collections. In experiments in vitro, Fau and Bcl-G levels in prostate cancer cell lines were reduced using RNA interference and the effects on sensitivity to UVC irradiation were determined. RESULTS Fau and Bcl-G mRNA levels were both lower in prostate cancer tissue than in normal prostate and Benign Prostate Hyperplasia. Active down-regulation of Fau and Bcl-G expression in vitro resulted in decreased sensitivity to UVC-induced cytotoxicity. Simultaneous down-regulation of Fau and Bcl-G produced a decrease in sensitivity which was similar to either gene alone. CONCLUSIONS Fau and Bcl-G mRNA levels are both decreased in prostate cancer. In prostate cancer cell lines in vitro such down-regulation results in reduced sensitivity to UVC-induced cytotoxicity, consistent with the putative roles of these genes as candidate prostate tumor suppressors. The absence of an additive effect when Fau and Bcl-G were down-regulated simultaneously is consistent with the two genes acting in the same apoptosis pathway, for example, with the pro-apoptotic effects of Fau being mediated through modulation of Bcl-G. Prostate 70: 1513,1523, 2010. © 2010 Wiley-Liss, Inc. [source] | ||||||||||