RESUMEN
OBJECTIVE: To measure free : total prostate specific antigen (PSA) ratios in ejaculate from men with suspected and known prostate cancer, and in young control men, to determine if this ratio might be useful in discriminating benign from malignant prostatic conditions. Patients, subjects and methods Forty-seven men with prostate cancer (positive biopsies), 52 men with suspected prostate cancer but who had negative biopsies and 28 young men (< 30 years old) and with no family history of cancer, provided either a single ejaculate specimen (total 59) or multiple specimens (total 193) on subsequent occasions. Free and total PSA were measured using appropriate assays. All specimens were diluted in a PSA-negative female serum pool. RESULTS: The median free : total PSA ratios were 0.76-0.81 among the patient groups and control men, and there was no statistical difference between the groups. These data presumably only reflect the inactive component of free PSA, given that any alpha2-macroglobulin or alpha1-antichymotrypsin in the assay serum diluent was likely to have bound the active free PSA component in these samples. Similar results were obtained from those providing single and multiple samples, suggesting that a single specimen is sufficient to reflect the seminal plasma free : total PSA ratio over that period. There was no relationship between seminal plasma free : total PSA ratio and age for the controls or the positive biopsy group, although there was a negative relationship (i.e. a decline with age) that almost reached significance in those with negative biopsies (P = 0.058, R2 = 0.07). CONCLUSIONS: This is the first report of free : total PSA ratios in the ejaculate of men with suspected and known prostate cancer compared with young control men. Although no significant changes were detected in the free : total PSA ratios in ejaculate, these results may be confounded by differences in ratios with age, as is the case for serum PSA or different molecular forms of PSA. Indeed, these data suggest that a large proportion of free PSA in seminal plasma may be inactive. Further studies are needed to determine the potential utility of measuring free : total PSA, or other candidate markers, in ejaculate to better discriminate benign from malignant prostate disease.
Asunto(s)
Antígeno Prostático Específico/análisis , Neoplasias de la Próstata/diagnóstico , Semen/química , Adulto , Anciano , Estudios de Casos y Controles , Humanos , Inmunoensayo/métodos , Masculino , Persona de Mediana EdadRESUMEN
The necessary first step in successful organ cryopreservation will be the maintenance of endothelial cell integrity during perfusion of high concentrations of cryoprotective agents (CPAs). In this report we compare the effects of incubation on cultured porcine endothelial cells at 10 degrees C for 1 h with the CPAs glycerol, dimethyl sulfoxide (Me2SO), ethanediol (EG), and propane-1,2-diol (PG) in the vehicle solutions RPS-2 (high potassium, high glucose) and HP-5NP (low potassium, high sodium), both with and without added colloids. Tritiated adenine uptake and acid phosphatase estimation of cell number were used as indicators of cell viability. HP-5NP was superior to RPS-2 except with Me2SO when the differences in viability were not significant. Adding Haemaccel to HP-5NP improved the results, but adding albumin to RPS-2 was of no significant benefit. Osmotic stress appeared to be the major problem with glycerols use. Beyond 3.0 M the toxicity of Me2SO increased dramatically but it could not be determined if this was osmotic or chemical toxicity. PG was remarkably well tolerated to 3.0 M but a sharp decrease in cell viability beyond this concentration suggests that PG may be most useful with mixtures of other CPAs. Overall, EG appeared to be the least toxic CPA and in the context of vascular preservation warrants further investigation.
Asunto(s)
Crioprotectores/toxicidad , Endotelio Vascular/efectos de los fármacos , Adenina/metabolismo , Animales , Transporte Biológico Activo/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Células Cultivadas , Dimetilsulfóxido/toxicidad , Evaluación Preclínica de Medicamentos , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Glicoles de Etileno/toxicidad , Glicerol/toxicidad , Propilenglicol , Glicoles de Propileno/toxicidad , SolucionesRESUMEN
Since the quality of renal preservation following simple ice storage is improved by the use of hyperosmolar washout solutions, hyperosmolar perfusates were evaluated for continuous perfusion preservation. Canine kidneys were preserved for 48 hours by continuous perfusion at 5 degrees C, using hyperosmolar cryoprecipitated plasma and 5% albumin perfusates of osmolalities 397 to 430 mOsm/kg H2O. Hyperosmolar plasma gave significantly better preservation than isosmolar plasma, but the results were only marginally superior to those already obtainable with isosmolar albumin solution. No further improvement in preservation by albumin perfusion was obtained with the hyperosmolar formulations. Because isosmolar albumin solution is easier to prepare than hyperosmolar cryoprecipitated plasma and gives comparable results, it remains our perfusate of choice for continuous perfusion preservation.