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71.
OBJECTIVES: Invasive penile and urethral tumors are traditionally treated with aggressive excision that requires involved organ and adjacent organ sacrifice. An alternative approach seeks to completely excise the tumor with adequate margins while preserving form and function of the organ. We present 6 patients who underwent such organ-sparing surgery. METHODS: Six selected cases (4 penile and 2 urethral) are presented with operative photographs and pertinent data. RESULTS: Three distal tumors of the penis were treated with excision limited to the glans with histopathologic findings of verrucous carcinoma, melanoma, and angiosarcoma. One patient with squamous cell carcinoma of the distal shaft refused partial penectomy and underwent a local wedge resection. A patient with locally advanced bulbourethral transitional cell carcinoma (TCC) refused cystourethrectomy and underwent an anterior urethrectomy and perineal urethrostomy. A 48-year-old woman with an adenocarcinoma contained in a very distal urethral diverticulum underwent simple diverticulectomy and excision of distal urethra. Postoperative voiding and sexual function were well preserved. Follow-up was 12 to 48 months. The patient with angiosarcoma died of lung metastases at 48 months with no local disease, and the patient with bulbourethral TCC developed pelvic disease at 12 months with no local recurrence and died of metastases at 25 months. CONCLUSIONS: Organ-sparing surgery is appropriate in selected patients on the basis of stage and location, high risk of distant failure, and patient disposition. Close follow-up is necessary. Comanagement with reconstructive and oncologic specialists optimizes results and outcomes. 相似文献
72.
F Carnino G Fuda G Ciccone L Iskra E Guercio D Dadone PF Conte 《Canadian Metallurgical Quarterly》1997,65(3):467-472
Dendritic cells (DC) are a subset of leukocytes whose major function is antigen presentation. We investigated the phenotype and function of enriched (95-98.5%) rat DC. We show that both spleen and thymus DC express the natural killer cell receptor protein 1 (NKR-P1) as a disulfide linked homodimer of 60 kD. Freshly isolated DC express a low level of NKR-P1, which is strongly upregulated after overnight culture. Spleen, but not thymus DC, were able to kill the NK-sensitive YAC-1 cell line in vitro, and since this killing was Ca2+ dependent, a Fas ligand-Fas interaction was probably not involved. Besides their potent antigen-presenting function, DC can thus be cytotoxic for some tumor targets. 相似文献
73.
74.
EW Steyerberg HJ Keizer SD Foss? DT Sleijfer GC Toner H Schraffordt Koops PF Mulders JE Messemer K Ney JP Donohue 《Canadian Metallurgical Quarterly》1995,13(5):1177-1187
PURPOSE: To develop a statistical model that predicts the histology (necrosis, mature teratoma, or cancer) after chemotherapy for metastatic nonseminomatous germ cell tumor (NSGCT). PATIENTS AND METHODS: An international data set was collected comprising individual patient data from six study groups. Logistic regression analysis was used to estimate the probability of necrosis and the ratio of cancer and mature teratoma. RESULTS: Of 556 patients, 250 (45%) had necrosis at resection, 236 (42%) had mature teratoma, and 70 (13%) had cancer. Predictors of necrosis were the absence of teratoma elements in the primary tumor, prechemotherapy normal alfa-fetoprotein (AFP), normal human chorionic gonadotropin (HCG), and elevated lactate dehydrogenase (LDH) levels, a small prechemotherapy or postchemotherapy mass, and a large shrinkage of the mass during chemotherapy. Multivariate combination of predictors yielded reliable models (goodness-of-fit tests, P > .20), which discriminated necrosis well from other histologies (area under the receiver operating characteristic (ROC) curve, .84), but which discriminated cancer only reasonably from mature teratoma (area, .66). Internal and external validation confirmed these findings. CONCLUSION: The validated models estimate with high accuracy the histology at resection, especially necrosis, based on well-known and readily available predictors. The predicted probabilities may help to choose between immediate resection of a residual mass or follow-up, taking into account the expected benefits and risks of resection, feasibility of frequent follow-up, the financial costs, and the patient's individual preferences. 相似文献
75.
76.
This review highlights recent research on the properties and functions of the enzyme transketolase, which requires thiamin diphosphate and a divalent metal ion for its activity. The transketolase-catalysed reaction is part of the pentose phosphate pathway, where transketolase appears to control the non-oxidative branch of this pathway, although the overall flux of labelled substrates remains controversial. Yeast transketolase is one of several thiamin diphosphate dependent enzymes whose three-dimensional structures have been determined. Together with mutational analysis these structural data have led to detailed understanding of thiamin diphosphate catalysed reactions. In the homodimer transketolase the two catalytic sites, where dihydroxyethyl groups are transferred from ketose donors to aldose acceptors, are formed at the interface between the two subunits, where the thiazole and pyrimidine rings of thiamin diphosphate are bound. Transketolase is ubiquitous and more than 30 full-length sequences are known. The encoded protein sequences contain two motifs of high homology; one common to all thiamin diphosphate-dependent enzymes and the other a unique transketolase motif. All characterised transketolases have similar kinetic and physical properties, but the mammalian enzymes are more selective in substrate utilisation than the nonmammalian representatives. Since products of the transketolase-catalysed reaction serve as precursors for a number of synthetic compounds this enzyme has been exploited for industrial applications. Putative mutant forms of transketolase, once believed to predispose to disease, have not stood up to scrutiny. However, a modification of transketolase is a marker for Alzheimer's disease, and transketolase activity in erythrocytes is a measure of thiamin nutrition. The cornea contains a particularly high transketolase concentration, consistent with the proposal that pentose phosphate pathway activity has a role in the removal of light-generated radicals. 相似文献
77.
MG Di Bello E Masini C Ioannides J Fomusi Ndisang S Raspanti T Bani Sacchi PF Mannaioni 《Canadian Metallurgical Quarterly》1998,47(3):122-130
Techniques such as positron-emission tomography, single-photon-emission computed tomography, functional magnetic-resonance imaging and magnetoencephalography permit the observation of biological processes in the brain in a noninvasive manner. They have yielded new insights into the biological interrelations of sensory, motor and cognitive functions, as well as into brain diseases. Combined use of these techniques may provide more information than just the sum of its constituents, and this may narrow the gap between the biological data provided by these techniques and the mental models described by clinicians, mathematicians, psychologists and philosophers. 相似文献
78.
K Aabo M Adams P Adnitt DS Alberts A Athanazziou V Barley DR Bell U Bianchi G Bolis MF Brady HS Brodovsky H Bruckner M Buyse R Canetta V Chylak CJ Cohen N Colombo PF Conte D Crowther JH Edmonson C Gennatas E Gilbey M Gore D Guthrie BY Yeap 《Canadian Metallurgical Quarterly》1998,78(11):1479-1487
The purpose of this systematic study was to provide an up to date and reliable quantitative summary of the relative benefits of various types of chemotherapy (non-platinum vs platinum, single-agent vs combination and carboplatin vs cisplatin) in the treatment of advanced ovarian cancer. Also, to investigate whether well-defined patient subgroups benefit more or less from cisplatin- or carboplatin-based therapy. Meta-analyses were based on updated individual patient data from all available randomized controlled trials (published and unpublished), including 37 trials, 5667 patients and 4664 deaths. The results suggest that platinum-based chemotherapy is better than non-platinum therapy, show a trend in favour of platinum combinations over single-agent platinum, and suggest that cisplatin and carboplatin are equally effective. There is no good evidence that cisplatin is more or less effective than carboplatin in any particular subgroup of patients. 相似文献
79.
MJ Lizak EF Secchi JW Lee S Sato E Kubo Y Akagi PF Kador 《Canadian Metallurgical Quarterly》1998,39(13):2688-2695
PURPOSE: To investigate flux through the polyol pathway in the dog lens by 19F-nuclear magnetic resonance (19F-NMR) spectroscopy, using 3-fluoro-3-deoxy-D-glucose (3-FG) as a substrate. METHODS: 3-FG metabolism was monitored by 19F-NMR analysis. Dog lenses were incubated in Dulbecco's modified Eagle's medium containing 10 mM 3-FG. Enzymatic reductase and dehydrogenase activities were spectrophotometrically determined, whereas the analyses of 3-FG metabolites were conducted by 19F-NMR analysis. Aldose reductase (AR) was immunohistochemically localized in dog lens with antibodies raised against dog kidney AR. RESULTS: 19F-NMR spectra indicate that incubation of purified dog lenses AR with 3-FG results in the formation of 3-fluoro-3-deoxy-D-sorbitol (3-FS) and that incubation of dog liver sorbitol dehydrogenase (SDH) with 3-FS results in the formation of 3-fluoro-3-deoxy-D-fructose (3-FF). This confirms that 3-FG is metabolized to 3-FF by the polyol pathway enzymes. The affinity (Km) of AR for 3-FG is approximately 20-fold better than that for D-glucose, whereas the Km of SDH for 3-FS was fourfold less than for D-sorbitol. 3-FG in cultured dog lenses is metabolized primarily to 3-FS; however, small amounts of 3-FF and 3-fluoro-3-deoxy-D-gluconic acid (3-FGA) are also formed. 3-FS formation was reduced by the AR inhibitor AL 1576, and 3-FF formation was eliminated by the SDH inhibitor CP-166,572. In dog lens epithelial cells cultured with 3-FG, only 3-FS is formed. Similarly, only 3-FS is formed when lens capsule containing primarily epithelial lens contaminated with superficial epithelial cells was incubated in 3-FG. Similar incubation of the remaining cortex resulted primarily in the formation of 3-FS and 3-FGA. This enzymatic distribution was confirmed by spectrophotometric activity analysis and the immunohistochemical localization of AR. CONCLUSIONS: The data confirm that flux through the polyol pathway primarily results in sorbitol accumulation. The absence of fructose and gluconic acid from cultured lens epithelium suggests that the epithelial cells primarily contain AR, whereas differentiated fiber cells also contain SDH and glucose dehydrogenase. 相似文献
80.
MA van Rossum TJ Fiselier MJ Franssen AH Zwinderman R ten Cate LW van Suijlekom-Smit WH van Luijk RM van Soesbergen NM Wulffraat JC Oostveen W Kuis PF Dijkstra CF van Ede BA Dijkmans 《Canadian Metallurgical Quarterly》1998,41(5):808-816
AIMS: To determine whether left ventricular volumes and ejection fractions calculated from single plane two-dimensional echocardiograms using the algorithm (0.85A2L) correlate with those calculated using the biplane Simpson's method, and whether small changes in volumes and ejection fraction occurring post-infarction could be detected from single-plane as well as from biplane two-dimensional echocardiograms. METHODS AND RESULTS: Serial two-dimensional echocardiograms were obtained in 371 patients from the DEFIANT II trial a mean of 2 days, 1 week and 6 months post-infarction. Single plane volumes from the apical four chamber and apical long axis correlated closely with biplane Simpson's left ventricular volumes. Both single-plane left ventricular volumes significantly over-estimated biplane Simpson's volumes. Biplane Simpson's ejection fractions were consistently slightly under-estimated from the single-plane images. Differences between biplane Simpson's and single-plane volumes increased independently with increasing left ventricular size and distortion. The small changes in left ventricular volumes and ejection fraction over time were as reliably detected from single plane as from biplane images. CONCLUSION: Single-plane left ventricular volumes over-estimate biplane Simpson's volumes and under-estimate ejection fraction, and these discrepancies are amplified in dilated hearts with abnormal shape. 相似文献