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J L Chin

Publications and source records attributed to J L Chin.

At least 37 records · Page 2Linked to original sources

Metallothionein expression in renal cancer.

OBJECTIVES: To assess metallothionein (MT) expression with immunohistochemical localization in human renal cell carcinoma and to determine whether a possible relationship with the histopathologic findings, tumor grade, or pathologic tumor stage is demonstrable, because MT may have a role in carcinogenesis. METHODS: Archival pathologic specimens and medical records were reviewed for 28 patients with renal cell carcinoma. Immunohistochemical localization of MT was performed with a polyclonal-antibody-to-rat-liver MT, an anti-rabbit IgG linking antibody, and an avidin-biotin horseradish peroxidase complex. Correlation was sought between immunohistochemical data (MT staining intensity, extension, and subcellular site) and clinical data (histologic cell type, tumor grade, and pathologic stage). RESULTS: The mean patient age was 61.7 years (range 42 to 86). The predominant histologic cell type was the clear cell variant. Three, sixteen, and nine tumors were pathologically staged as 1, 2, and 3, respectively. There were 1, 13, 10, and 4 tumors with grades 1, 2, 3, and 4, respectively. Among the independent variables, greater immunoreactivity was observed in Stage 2 tumors (P = 0.028). A significant inverse relationship between tumor grade and MT staining intensity was also observed (P = 0.007). CONCLUSIONS: The inverse relationship in renal cell carcinoma between MT immunoreactivity and tumor grade may indicate a role for MT in tumor growth and dedifferentiation. Increased MT immunoreactivity in lower stage tumors may be related to rapid tumor growth during their growth cycle. Further study is required to elucidate the role of MT in renal cell carcinoma oncogenesis and its possible use as a clinical prognostic parameter.

Adult↗

Three-dimensional transrectal ultrasound guided cryoablation for localized prostate cancer in nonsurgical candidates: a feasibility study and report of early results.

PURPOSE: A 3-dimensional (D) transrectal ultrasound imaging system was incorporated into the cryoablation routine for prostate cancer to assess its feasibility and use. The objective was to improve visibility for probe placement and for intraoperative monitoring. MATERIALS AND METHODS: A commercially available transrectal ultrasound unit was coupled with a custom designed software system to construct 3-dimensional prostate images. A total of 52 patients with clinically localized prostate cancer, in whom radiotherapy had failed (45) or who were otherwise judged to be nonsurgical candidates (7) were treated with cryoablation, using 3-D transrectal ultrasound for intraoperative guidance. RESULTS: In all cases the intraoperative 3-D transrectal ultrasound images provided a unique coronal view of the prostate, revealing useful information and facilitating more precise probe placement and treatment monitoring. Early postoperative histological and biochemical results and complication rates compare well with other contemporary series. CONCLUSIONS: Although the precise role of cryoablation in the management of prostate cancer remains unclear and long-term results are pending, incorporation of a 3-D transrectal ultrasound imaging system into the cryoablation routine proved to be feasible and appeared to be a worthwhile effort to facilitate the procedure, and deserves further evaluation.

Cryosurgery↗

Renal autotransplantation for the loin pain-hematuria syndrome: long-term followup of 26 cases.

PURPOSE: We review the long-term results of renal autotransplantation as a form of nephron sparing renal denervation for patients with the loin pain-hematuria syndrome. MATERIALS AND METHODS: From 1985 to 1997, after exclusion of other urological, nephrological and psychiatric causes for severe intractable flank pain and recurrent hematuria, 22 patients with severe debility and heavy narcotic dependency underwent 26 renal autotransplantations for pain control. Postoperative pain relief, narcotic use, level of function in daily activities and status of the autograft were assessed. RESULTS: Median and mean followup was 78.5 and 84.7 months (range 30 to 138), respectively. There were 2 technical failures. Pain recurred within 2 years after 6 procedures, of which 3 resulted in transplant nephrectomy and 3 were managed with a reduced analgesic requirement. Of the 16 patients with minimum 5 years of followup 12 (75%) were pain-free after surgery with 3 additional patients pain-free after transplant nephrectomy. Overall, 18 of the 26 autotransplant procedures (69.2%) resulted in pain relief, in some cases beyond 10 years, with patients returning to normal daily activities. CONCLUSIONS: Renal autotransplantation results in durable narcotic-free favorable results in the majority of meticulously screened loin pain-hematuria syndrome patients. Although some failures, which usually occur within 2 years after surgery, can be expected, autotransplantation is justified as a nephron sparing denervation therapy for select loin pain-hematuria syndrome patients.

Adult↗

Autoantigen recognition by human CD8 T cell clones: enhanced agonist response induced by altered peptide ligands.

Determination of immunodominant epitopes of MHC class I-restricted self-Ags and elucidation of TCR contact residues is of potential importance in providing a means of manipulating the immune response to self-Ags in human autoimmune diseases. A computer algorithm was used to examine the sequences of the two major encephalitogenic proteins of myelin, MBP and PLP, for HLA-A2 binding motifs. Thirty-eight peptides with HLA-A2.1 binding motifs were synthesized and their binding to HLA-A2.1 was measured. A panel of HLA-A2-restricted T cell clones directed against the PLPp80-88 epitope, which exceeded the binding affinity of the other myelin-peptides tested by at least one order of magnitude, was generated. Using a set of analogue peptides with single amino acid substitutions, we detected a distinct pattern of TCR contact residues for each clone. Surprisingly, modification of different presumed TCR contact residues generated superagonist peptides, which are defined as peptides with equal or lower MHC binding affinity to HLA-A2 that induce half-maximal effector responses at 100-fold lower concentrations than the original peptide. These agonist peptides could drive cytotoxic T cell clones to proliferate, secrete cytokines, and clonally expand at concentrations at which the native peptide induced only cytotoxic responses. The proliferation induced by the superagonist peptides gives additional evidence that the clonal expansion of CD8 T cell clones may in part be regulated on the level of Ag recognition by the TCR.

Amino Acid Substitution↗

Molecular cloning and gene expression analysis of PSP94 (prostate secretory protein of 94 amino acids) in primates.

Prostate secretory protein of 94 amino acids (PSP94) has shown the potential to be a diagnostic biomarker and a therapeutic agent for prostate cancer. Primates have been the main animal models for studying the biology of this molecule. We have cloned and analyzed the cDNA and promoter region of PSP94 from baboon (Papio anubis). Sequence divergence among baboon, monkey, pig, and human, in both the exons and 5'-flanking region indicates rapid evolution of the PSP94 gene. There are conserved steroid hormone response elements (SHRE) in the promoter region of all three primate species. Multiple, alternative transcripts starting near these SHREs and upstream to the TATA box were identified by reverse transcriptase polymerase chain reaction (RT-PCR) and rapid amplification of 5'-cDNA ends (5' RACE) in primate prostatic tissues. This differential transcription initiation may be linked to androgen regulation of PSP94 gene expression. PSP94 transcripts were detected by RT-PCR in a wide variety of mucus-secreting tissues. However, the alternative transcripts were found only in the prostate. The distribution of the PSP94 protein in baboon secretory tissues was also examined by Western blot analysis using a polyclonal antibody against the human homolog. A positive immunoreactive band was detected, but it was weak, due probably to epitope divergence between the two species. In all young, healthy primate animals tested, the level of immunoreactive PSP94 in prostate tissues was lower than expected. In addition, RT-PCR combined with Southern blot analysis on prostate tissues in these animals failed to detect the PSP57 mRNA produced by alternative splicing of PSP94 primary transcript. These observations can be explained by the sexual immaturity and incomplete prostate development in these young primates. This explanation was supported by histological examination of their prostate during PSP94 immunohistochemistry.

Amino Acid Sequence↗

DNA cytometric proliferative index predicting organ confinement in clinical stage-B prostate cancer.

PURPOSE: To assess nuclear activity by DNA flow cytometry (FCM), Gleason score and serum prostate-specific antigen (PSA) levels in predicting extracapsular tumour involvement in patients with prostate cancer. DESIGN: Retrospective pathologic study. PATIENTS: Forty patients with clinical stage-B prostate cancer who underwent radical prostatectomy. INTERVENTIONS: The relationship between the pathologic state and each of the proliferative index (PI). Gleason score and PSA level was analysed retrospectively with the use of archival specimens. Preoperative serum PSA levels, were measured by the Hybritech assay. Gleason score was determined by 2 of the authors. Tumours were classified as stage B (confined to prostate), C1 (focal capsular penetration) or C2 (involvement of seminal vesicles or capsular perforation). FCM PI measurements were performed on deparaffinized tumour specimens. RESULTS: All 40 specimens were diploid. There were 9 pathologic stage-B, 16 stage-C1 and 15 stage-C2 tumours. The serum PSA level was 20 ng/mL or less for all patients except 2, for whom the levels were 27.8 ng/mL and 45.9 ng/mL, respectively. A Gleason score lower than 7 had a 76.0% sensitivity and 53.5% specificity in predicting organ confinement. In contrast, a PI of 21 or lower had a 84.0% sensitivity and a 73.0% specificity in predicting organ confinement, with a positive predictive value of 84.0%. Of the 17 tumours with both "favourable" features (Gleason score lower than 7 and PI of 21 or lower), only 1 (5.9%) had extracapsular involvement (stage C2). Of the 6 tumours with both "unfavourable" features (Gleason score higher than 7 and PI of 21 or higher) 5 of 6 were stage C2 and 1 was stage C1. CONCLUSION: The single most consistent predictor of organ confinement was PI alone.

Cell Division↗

Analysis of epitope structure of PSP94 (prostate secretory protein of 94 amino acids): (I). Immuno-dominant and immuno-recessive area.

PSP94 is a potential biomarker for evaluating patients with prostate carcinoma. We have systematically studied the epitope structure of PSP94 by using a polyclonal antibody against human PSP94. Results of peptide mapping and ELISA tests of dose response to rabbit antiserum against human PSP94 protein showed that only the N-terminal peptides (N30 and M23) are immunoreactive while all the synthetic peptides (C28, C10) located closer to the C-terminus are completely devoid of antigenic activity with the polyclonal antibody. These results were confirmed by analysis of reciprocal competitive binding of PSP94 polyclonal antibody by the N-terminal peptides (N30 and M23) v. either recombinant GST-PSP94 fusion protein, purified recombinant PSP94, or natural PSP94 protein. To further delineate the antigenic activity of the N- and C-termini, we have also expressed N- and C-terminal half of the whole PSP94 (each 47 peptides) using the E. coli GST expression system. The recombinant N47/C47 peptides were released by thrombin cleavage from the GST fusion protein and characterized by Western blotting experiments. Dose response of the recombinant GST-PSP-N47 and -C47 peptides to PSP94 polyclonal antibody showed differential binding activities. Competitive binding of these recombinant N47/C47 proteins against the GST-PSP94 protein demonstrates that the polyclonal antibody has a higher affinity for the N47 peptide than the C47 peptide. Based on the immunological studies of both synthetic peptides and recombinant PSP94- N/C terminal proteins, we propose an epitope structure of human PSP94 with an immuno-dominant N-terminus and an immuno-recessive C-terminus.

Amino Acid Sequence↗

Analysis of epitope structure of PSP94 (prostate secretory protein of 94 amino acids): (II). Epitope mapping by monoclonal antibodies.

PSP94 has shown potential to be a serum biomarker for evaluating prostate cancer. Studies of the epitope structure is crucial for this endeavour. In this article, we have used 15 different monoclonal antibodies (MAb) to analyse the epitope structure of PSP94 and to compare with the results obtained from our previous work using polyclonal antibody and recombinant PSP94. Firstly, we determined the relative activities of the 15 MAb population by direct and competitive ELISA. The two predominant MAbs (MAb PSP-6 and -19) in 15 MAbs were selected for further studies of the epitope structure. By comparing the binding activities of recombinant GST-PSP94 and natural PSP94 with MAbs, and by comparing their affinity with MAbs in an in vitro denaturing experiment, PSP94 was shown to have a similar, prevalently linear epitope structure as we demonstrated by polyclonal antibody. Using recombinant GST fusion protein with PSP94 and with each half of the N- and C-terminal 47 amino acids (GST-PSP-N47/C47) in E. coli cells, the different epitopes recognized by 15 monoclonal antibodies were delineated and the polar distribution of the epitope structure of PSP94 was characterized. Results of direct ELISA of recombinant N47 and C47 and their competitive binding against natural PSP94 (competitive ELISA) showed that the N- and C-termini represent the immuno-dominant and immuno-recessive area separately. A majority of the monoclonal antibodies (12/15) showed preferential binding of the N-terminal sequence of the PSP94 protein. Using GST-PSP-N47 as a standard protein, an epitope map of the 15 monoclonal antibodies was obtained. The results of this study will help to define the clinical utility of PSP94.

Animals↗

Genetically regulated response to intravesical bacillus Calmette Guerin immunotherapy of orthotopic murine bladder tumor.

PURPOSE: Genetically regulated host response to intravesical Bacillus Calmette Guerin (BCG) immunotherapy was assessed using the murine bladder tumor MM45T in Bcgr and Bcgs inbred congenic strains of mice. MATERIALS AND METHODS: Tumor detection and monitoring of treatment response to BCG was carried out using magnetic resonance imaging (MRI) of BALB/c (Bcgs allele) and BALB/c. CD2 (CD2) (Bcgr allele) mice implanted orthotopically with MM45T tumor cells. Intravesical BCG instillation (3 doses per week for 3 weeks) was used as prophylaxis against tumor implantation in both Bcgr and Bcgs strains and as definitive treatment against MRI-confirmed established tumors. Tumors implanted in both strains of untreated mice served as controls. Intravesical injection of BCG was also performed in established heterotopic subcutaneous tumors in both strains. Immunologic response in all groups was assessed by flow cytometric analysis of the bladder irrigation fluid cell composition, measuring CD4+ (helper/inducer) and CD8+ (cytotoxic/ suppressor) cell subsets. RESULTS: Intralesional injection of BCG into established heterotopic tumors showed growth inhibition in the Bcgs strain but not in the Bcgr strain. Intravesical BCG treatment against established orthotopic tumors showed significant tumor regression in the Bcgs strain compared to control but there was no effect in the Bcgr strain. CONCLUSION: The differential anti-tumor activity of BCG in the Bcgs and Bcgr congenic murine strains supports the notion that Bcg gene-controlled responsiveness to BCG innoculation determines, at least partially, the host response to immunotherapy. These results have potential clinical significance in patient selection for intravesical therapy for bladder cancer.

Adjuvants, Immunologic↗

Metallothionein expression in prostatic carcinoma: correlation with Gleason grade, pathologic stage, DNA content and serum level of prostate-specific antigen.

OBJECTIVE: To determine the expression of metallothionein (MT) in prostatic carcinoma by immunohistochemical staining. Several lines of evidence have indicated that MT may play a role in carcinogenesis and in drug resistance of tumours. DESIGN: Retrospective pathologic study. INTERVENTIONS: Formalin-fixed, paraffin-embedded archival tissues from 39 radical prostatectomies were analysed. All tumour foci were stained by ABC technique using a primary polyclonal rabbit antibody against rat liver MT. The staining intensity for MT was graded on a scale of 0 to 2+, and the histologic grading was done by the scheme of Gleason. OUTCOME MEASURES: Correlation of MT expression with Gleason grade, preoperative serum prostate-specific antigen (PSA) levels, pathologic stage and DNA content, including S-phase fraction (SPF) and proliferative index (PI). RESULTS: Most of the epithelium of normal prostate tissue had patchy, intense MT staining. All the grade II tumours foci showed intense (2+) staining for MT, while all grade IV and V foci were persistently negative. The grade III tumours foci were heterogeneous. The MT-positive foci showed both nuclear and cytoplasmic staining of variable extent. There were 9, 15, 13 and 2 tumours with pathologic stage B, C1, C2 and D1, respectively. The serum PSA levels ranged from 1 to 16 ng/mL. No apparent correlation existed between the MT staining pattern and the pathologic stage or preoperative PSA level. Thirty-four of the tumours were diploid and 5 were tetraploid. There were significantly higher SPF and PI mean values in the MT-stained tumour cells (p < 0.05), suggesting that MT preferentially stains an epithelial subpopulation, possibly the proliferating cell compartment. CONCLUSION: The positive correlation of MT expression with Gleason grade in prostatic adenocarcinoma suggests a possible role for MT in oncogenesis in prostate cancer.

Biomarkers, Tumor↗

Recombinant PSP94 (prostate secretory protein of 94 amino acids) demonstrates similar linear epitope structure as natural PSP94 protein.

PSP94 has the potential to be a useful diagnostic marker and therapeutic agent in prostate cancer. Recently, different immunoassay systems for quantitative analysis of PSP94 in clinical samples have been developed, but the epitope structure of PSP94 protein has not been elucidated. In this study, we report an Escherichia coli expression system for recombinant GST-PSP94 fusion protein. GST-PSP94 contains antigenic determinants similar to natural PSP94 protein (determined both by Western blotting experiments and by ELISA) and can be used to study the structure of natural PSP94 antigen. Since GST-PSP94 was expressed in E. coli and purification involved a denaturing process, we propose that the epitope structure of PSP94 is linear and largely dependent on the primary amino acid sequence, rather than conformational structure. This hypothesis was supported by reciprocal competition in ELISA among natural, GST-PSP94 fusion protein, and purified recombinant PSP94 protein. The results demonstrate that the various forms of PSP94 can compete with each other in binding to rabbit PSP94 polyclonal antibody, although the natural PSP94 has a slightly higher affinity. When natural and recombinant PSP94 protein were denatured in vitro with urea and alkali, no effect on the binding to antibody was found. The epitope activity of natural PSP94 was also shown to be resistant to the treatment of detergent and reducing agent. The location of one of the linear epitopes recognized by the PSP94 antibody was determined to be in the N-terminus by using two synthetic peptides representing N- and C-terminal sequences. Competitive ELISA between the N-terminal peptide and PSP94 protein indicate that both natural and GST-PSP94 have similar immunoactive N-termini.

Animals↗

Mycobacterium cell wall: an alternative to intravesical bacillus Calmette Guerin (BCG) therapy in orthotopic murine bladder cancer.

PURPOSE: The antitumor effect of intravesical mycobacterium cell wall (MCW) therapy on orthotopic and heterotopic bladder tumors in the mouse was assessed with magnetic resonance imaging (MRI). MATERIALS AND METHODS: The live bacillus Calmette Guerin (BCG) organism was replaced with a cell wall extract derived from the outer capsule of Mycobacterium phlei. This alternative form of intravesical therapy was used with the aim of reducing the toxicity associated with the live mycobacterium organism without compromising efficacy. Response to multiple doses of intravesical MCW and BCG was assessed in mice with established MBT-2 tumors after transurethral tumor implantation. RESULTS: Serial MRI of BCG-treated mice revealed significant tumor regression. The MR images correlated well with the corresponding histology of the whole mount bladder sections. Treatment with MCW also resulted in significant inhibition of tumor growth compared with control untreated animals (p < 0.05) although the antitumor effect was less pronounced than that of live BCG. Treatment was well tolerated in the MCW group with no apparent ill effects. Flow cytometric (FCM) analysis of bladder washings with phenotype-specific monoclonal antibodies revealed predominantly a CD3+ T cell infiltrate in the control and BCG-treated as well as the MCW-treated mice. The CD4+ (helper/inducer) subset of T cells predominated over the CD8+ (suppressor/cytotoxic) subset in both the BCG- and MCW-treated animals, and the CD4+/CD8+ ratio in both of the treated groups differed significantly from that of the control untreated groups. CONCLUSION: Intravesical MCW appears to invoke a similar inflammatory response in the mouse bladder mucosa as the live BCG organism and retains an antitumor action. It deserves further evaluation as a potential antitumor agent against bladder cancer. A Phase II clinical trial is now underway.

Adjuvants, Immunologic↗

Three-dimensional prostate ultrasound and its application to cryosurgery.

Transrectal ultrasound (TRUS), despite its undeniable utility in prostate imaging, employs a spatially flexible and variable 2-dimensional (2-D) imaging technique to visualize a 3-dimensional (3-D) disease process and anatomy. To circumvent some of the limitations of 2-D TRUS, 3-D TRUS was developed. The system consists of a motorized assembly (to hold a standard ultrasound transducer) and a computer with a video frame grabber. The microcomputer, using software developed in our laboratory, rapidly reconstructs a series of linear ultrasound images into a 3-D image. The 3-D TRUS technology has been incorporated into our program for cryoablation of the prostate. With intraoperative 3-D TRUS providing a unique coronal view, cryoprobe placement is facilitated to detect malalignment and avoid subsequent suboptimal cryoablation. In our use of 3-D TRUS guidance, in all 21 initial patients, probe malalignment, otherwise not apparent on standard 2-D TRUS, was detected and corrected before cryosurgery. With median follow-up of just < 1 year, only 2 of 44 biopsy cores (from the same site of 1 patient) were positive at 3 and 6 months. 3-D TRUS appears to be a valuable adjunctive tool in prostate imaging, especially in providing guidance for cryoblation of prostate cancer.

Cryosurgery↗

Alternative splicing of PSP94 (prostatic secretory protein of 94 amino acids) mRNA in prostate tissue.

While performing reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of total mRNA from prostate cancer specimens, two forms of PSP94 cDNA were detected. RT-PCR products were analysed by Southern blotting and probing with exon-specific oligonucleotides. In the short form of PSP94 mRNA, designated as PSP57, exon III was found to be deleted. The two mRNA forms were confirmed by cloning and sequencing of the RT-PCR products and were found to result from alternative splicing. The alternatively spliced form, PSP57, was characterized by sequence analysis. PSP94 and PSP57 possess identical exons I and II, including identical secretion signal peptide and the 5' untranslated sequences. PSP57 has a frame-shifted exon IV and encodes a putative 57 amino acid protein with a novel, highly basic C-terminus of 41 amino acids. PSP57 mRNA was detected in other urogenital tissues (kidney, bladder) and in most tumor cell lines tested, but was not detectable in other tissues such as breast and lung. In prostate tumor cell lines, PSP57 mRNA was aberrantly spliced and localized in the nuclear fraction of the cell. Our results suggest the possible existence of a novel PSP protein that originates from alternative splicing of PSP94 mRNA in urogenital tissues.

Aged↗

Induction of hepatic metallothionein I in tumour-bearing mice.

Metallothionein (MT) is an intracellular metal-binding protein which has been implicated in various biological roles, including heavy-metal detoxification and zinc and copper homeostasis, and has putative antioxidant properties. High levels of MT have been detected in certain human tumours, but its functions are unclear. The presence of tumour may cause stress conditions along with alterations in host metabolism, such as the redistribution of metals and, subsequently, in changes in hepatic MT isoforms. The distribution of basal levels of MT-1 and MT-11 isoforms in livers of different strains of mice and their induction in mice inoculated with tumour cells are investigated. While Balb-c, C57/BL and CD1 mice strains had an equal distribution of both hepatic MT isoforms, MT-I and MT-II. In addition, MT-I was the predominant isoform synthesised (> 88%) in the livers of all strains of mice at 24 h after injection with either cadmium or zinc salts. After inoculation with human testicular T7800 or T7799 tumour cells, the major form of MT induced in the livers of nude (nu/nu) mice was Zn-MT-I, and its concentration was positively correlated with the size of the inoculated tumours (r2 = 0.85). A similar positive relation was found in the livers of Balb-c mice inoculated with MM45T mouse bladder tumour cells (r2 = 0.96). Following surgical removal of T7800 tumour, hepatic MT concentrations returned to basal values. There was an increase in plasma MT levels in tumour-bearing mice and it was positively correlated with the increase in hepatic MT levels. These results demonstrate a specific increase in hepatic MT-I isoform in tumour-bearing mice, and this may be due to a generalised stress during tumour growth.

Analysis of Variance↗

Metallothionein expression and resistance to cisplatin in a human germ cell tumor cell line.

Expression of intracellular metallothionein (MT) has been linked to cis-diamminedichloroplatinum (cDDP) resistance in human germ cell tumor cell lines. To determine whether exposure to cDDP would select for cells with increased MT expression, the MT content of the human teratocarcinoma cell line T7800 was measured after development of resistance to cDDP by exposure to progressively higher drug concentrations (6.25-25 microM). cDDP-resistant cells (T7800R) had significantly higher MT mRNA and MT protein, increased resistance to killing by cDDP and altered in vitro growth kinetics compared to parental T7800 cells. cDDP resistance in a variety of other human tumor cell lines correlated with MT content, with no significant difference in glutathione level. These data indicate that selection in vitro for cDDP resistance in human germ cell tumors coselects for cells with enhanced MT content. However, selected cells differed in characteristics other than MT content. They had a slower growth rate and, although the rank order of MT level in T7800, T7800R and other human tumor cell lines correlated very well with cDDP resistance, differences in the level of MT expression did not correspond with differences in the absolute level of cDDP resistance. These results suggest that increased MT expression is concomitant with increased cDDP resistance in a variety of human tumor cell lines. However, measured differences in MT levels may not accurately reflect the degree of cDDP resistance differences among those cells.

Cell Division↗

Fatal air embolism during radical retropubic prostatectomy.

Air embolism during urological surgery only rarely has been reported. We report a case of fatal air embolism occurring during radical retropubic prostatectomy. This entity is discussed in an attempt to raise the level of awareness of this rare but potentially lethal complication, especially in view of the ever increasing popularity of radical retropubic prostatectomy as the treatment for organ confined carcinoma of the prostate.

Aged↗

Self-contained, inflatable penile prosthesis: magnetic resonance appearance.

The appearance of an inflatable penile prosthesis, visualized on a short tau inversion recovery sequence, is reported, in a patient who had magnetic resonance imaging for pelvic pain subsequent to radical cystoprostatectomy for bladder carcinoma. With suppression of adjacent fat signal, the prosthesis is well delineated from adjacent structures. The fluid-containing cylinders of the prosthesis are of very bright signal intensity, with the relief valve assembly of low signal intensity.

Humans↗