ABSTRACT
Prostate-specific antigen (PSA) is a protease able to bind to serum antiproteases as alpha 1 antichymotrypsin (ACT). Free PSA (FPSA) corresponds to the fraction of total PSA (TPSA) which is unbound to ACT. Specific detection of the FPSA seems to be a valuable tool in the distinction between prostatic cancer (PCa) and benign prostatic hyperplasia (BPH). Our aim was to evaluate retrospectively the FPSA/TPSA ratio in comparison to TPSA or FPSA determination, using two new immunoradiometric assays (PSA-RIACT and FPSA-RIACT, CIS bio international, Gif Sur Yvette, France) in the early diagnosis of PCa. 256 men, with TPSA levels between 0.7 and 44.7 ng/ml (median age = 69 years), including 164 sera obtained from patients with BPH and 92 sera from patients with untreated PCa were assayed. All diagnoses were histologically confirmed and patients tested before any adjuvant treatment. The evaluation of the median FPSA/TPSA ratio in the two groups showed significantly different values (BPH group: 24.2%, PCa group: 12.1%, P < 0.0001). By R.O.C. (Receiver-Operating-Characteristics) analysis, we show that the FPSA/TPSA ratio is the method of choice for discriminating BPH and PCa, since the area under curve is the greatest for the FPSA/TPSA ratio curve, as compared to the TPSA or FPSA curves (P < 0.0001). The best accuracy (number of true positive + true negative/total = 82.4%) was obtained with a FPSA/TPSA ratio < or = 15% with high odds ratio (20.5; confidence interval (CI): 11.2; 37.7). Of interest, similar results were also confirmed even in the subpopulation with serum TPSA levels between 2.5 and 10 ng/ml (161 patients including 99 BPH and 62 PCa). We thus confirm that combined serum measurement of FPSA and TPSA is of particular interest in the early diagnosis of PCa for patients with non-suspicious digital rectal examination and a TPSA value between 2.5 and 10 ng/ml. In those patients, biopsy should be reserved to the cases with FPSA/TPSA below 15%, which allows significant odds ratio (12.8; CI: 5.2; 31.4). Otherwise, to avoid the risk of missing any PCa, usual follow-up with combined TPSA and FPSA determination would be required with the same criteria of biopsy (i.e. FPSA/TPSA ratio < or = 15% when TPSA value is between 2.5 and 10 ng/ml; or TPSA > 10 ng/ml).
Subject(s)
Biomarkers, Tumor/blood , Prostate-Specific Antigen/blood , Prostatic Neoplasms/diagnosis , Adult , Aged , Diagnosis, Differential , Humans , Immunoradiometric Assay , Male , Middle Aged , Prostatic Hyperplasia/diagnosis , ROC Curve , Reference Values , Retrospective Studies , Time FactorsABSTRACT
Itaconate biosynthesis was studied in intact cells of high-yield (RC4') and low-yield (CM85J) strains of the fungus Aspergillus terreus by methods (tracers, nuclear magnetic resonance spectroscopy, and mass spectroscopy) that did not interfere with metabolism. Itaconate formation in RC4' required de novo protein biosynthesis. Krebs cycle intermediates increased in both strains during the production of itaconic acid. The Embden-Meyerhof-Parnas pathway and the Krebs cycle were shown to be involved in this biosynthesis by using 14C- and 13C-labelled substrates and nuclear magnetic resonance spectroscopy. A metabolic pathway for itaconate formation from glucose in A. terreus is proposed.
Subject(s)
Aspergillus/metabolism , Succinates/metabolism , Aspergillus/enzymology , Aspergillus/growth & development , Carbon Isotopes , Carbon Radioisotopes , Chromatography, High Pressure Liquid , Citric Acid Cycle , Glucose/metabolism , Magnetic Resonance Spectroscopy , Pentose Phosphate Pathway , Protein Synthesis Inhibitors/pharmacologyABSTRACT
Cerebral SPECT studies with N-isopropyl-iodo-amphetamine (123I) (IMP) were performed in patients who had suffered cranio-facial trauma, with and without loss of consciousness (LOC). The results were compared with computed tomography (CT). Nine out of ten of those with LOC had normal CT scans and evident photopaenia in IMP studies. It is clear that IMP SPECT scans complement CT in the investigation of patients who have suffered cranio-facial trauma.
Subject(s)
Amphetamines , Brain Injuries/diagnostic imaging , Skull Fractures/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , Adolescent , Adult , Aged , Aged, 80 and over , Coma/diagnostic imaging , Female , Humans , Iodine Radioisotopes , Iofetamine , Male , Middle Aged , Tomography, X-Ray ComputedABSTRACT
Blood samples from 500 patients with clinical prostatic symptoms were radioimmunoassayed with prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) kits. On the basis of histological data, directed by PSA results and other investigations, 200 prostatic cancers (adenocarcinomas), 276 benign prostatic hypertrophy (BPH), 16 cases of prostatitis, 5 cancers of the bladder, and 3 prostatodynias were diagnosed. All of the serum samples from prostatic cancer patients showed elevated PSA levels at diagnosis, whereas about 70% of these showed normal PAP values. The sensitivity of the PSA assay is 100% when 2.5 ng/ml is taken as the upper limit of normal. However, the specificity and the positive predictive value are better at 10 ng/ml: 99 and 79%, respectively. High PSA values alerted the clinician when diagnosing a cancer without symptoms on rectal or ultrasonographic examination (3%). In BPH, when the PSA level is between 2.5 and 10 ng/ml, a PSA control must be performed within 2 months. If PSA increases above 10 ng/ml, the risk of cancer has to be considered. In the follow-up, PSA is a better marker than PAP to detect disease progression and seems to constitute an evolutive tumor mass index. PSA is the most sensitive, the earliest, and the most prognostically reliable marker for diagnosis and follow-up of prostate cancer patients.
