Proper cut-off value of free to total PSA ratio for detection of prostate cancer in Korean men

To assess whether the free-to-total prostate specific antigen (PSA) ratio (F/T PSA ratio) would enhance prostate cancer detection in Korean men with serum total PSA levels between 4 and 20 ng/ml. Methods: A total of 240 consecutive patients whose serum PSA levels were between 4 and 20 ng/ml were enrolled in this two-year study. All patients underwent ultrasound-guided transrectal biopsies of the prostate gland. The F/T PSA ratio was measured using the Roche immunoassay. Results: Of the 240 patients, 202 (84%) had benign histologies, while 38 (16%) had prostate cancer. The two patient groups were well matched for age. The mean F/T PSA ratio showed a statistically significant difference between the two groups: in the benign histology group it was 0.14 (0.04 - 0.37), and 0.10 (0.08 - 0.20) in the prostate cancer group (p < 0.05). Out of the 183 patients with a PSA level between 4-10 ng/ml, the mean F/T PSA ratios were 0.14 and 0.11 in the benign histology (n=158) and prostate cancer groups (n=25), respectively (p < 0.05). From the 57 patients with a PSA level between 10 - 20 ng/ml, the mean F/T PSA ratios were 0.14 and 0.10 in the benign histology (n=44) and prostate cancer groups (n=13), respectively (p < 0.05). Overall, when the cut-off value of the F/T PSA ratio was 0.10, the sensitivity and specificity were 75.0% and 76.5%, while for the cut-off value of 0.15 they were 83.3% and 39.7% respectively. Conclusion: Our data demonstrated the usefulness of the free to total PSA ratio in distinguishing benign prostate disease and cancer disease, hence eliminating unnecessary biopsies. It is recommended that a cut-off value for the F/T PSA ratio of 0.10 be applied to Korean men which this is lower than the value used in Western countries.     

Spontaneous disruption of mycotic aneurysm involving innominate artery

We report a case of ruptured mycotic aneurysm involving innominate artery requiring an urgent surgical treatment. A 62-yr-old woman presented with fever and dyspnea. Previously, she was diagnosed with colon cancer and received right hemicolectomy and one cycle of adjuvant chemotherapy. On echocardiogram, pericardial effusion was noted and emergency pericardiocentesis was performed. CT scan revealed aortic aneurysm involving ascending aorta and innominate artery, and thrombi surrounding those structures. Patch repair of the defect in the ascending aorta and ringed Goretex graft to bypass the innominate and ascending aorta were performed. We believe that this is the first case of ruptured mycotic aneurysm involving innominate artery.     

Detection and genotyping of Mycobacterium species from clinical isolates and specimens by oligonucleotide array

Identification of pathogenic Mycobacterium species is important for a successful diagnosis of mycobacteriosis. The purpose of this study was to develop an oligonucleotide array which could detect and differentiate mycobacteria to the species level by using the internal transcribed spacer (ITS) sequence. Using a genus-specific probe and 20 species-specific probes including two M. avium-intracellulare complex (MAC)-specific probes, we have developed an ITS-based oligonucleotide array for the rapid and reliable detection and discrimination of M. tuberculosis, MAC, M. fortuitum, M. chelonae, M. abscessus, M. kansasii, M. gordonae, M. scrofulaceum, M. szulgai, M. vaccae, M. xenopi, M. terrae, M. flavescens, M. smegmatis, M. malmoense, M. simiae, M. marinum, M. ulcerans, M. gastri, and M. leprae. All mycobacteria were hybridized with a genus-specific probe (PAN-03) for detection of the genus Mycobacterium. Mycobacterial species were expected to show a unique hybridization pattern with species-specific probes, except for M. marinum and M. ulcerans, which were not differentiated by ITS-based probe. Among the species-specific probes, two kinds of species-specific probes were designed for MAC in which there were many subspecies. The performance of the oligonucleotide array assay was demonstrated by using 46 reference strains, 149 clinical isolates, and 155 clinical specimens. The complete procedure (DNA extraction, PCR, DNA hybridization, and scanning) was carried out in 4.5 h. Our results indicated that the oligonucleotide array is useful for the identification and discrimination of mycobacteria from clinical isolates and specimens in an ordinary clinical laboratory.     

Elevated abeta42 in skeletal muscle of Alzheimer disease patients suggests peripheral alterations of AbetaPP metabolism

The levels of amyloid-beta40 (Abeta40) and Abeta42 peptides were quantified in temporalis muscles and brain of neuropathologically diagnosed Alzheimer disease (AD) and of nondemented individuals. This was achieved by using a novel analytical approach consisting of a combination of fast-performance liquid chromatographic (FPLC) size exclusion chromatography developed under denaturing conditions and europium immunoassay on the 4.0- to 4.5-kd fractions. In the temporalis muscles of the AD and nondemented control groups, the average values for Abeta42 were 15.7 ng/g and 10.2 ng/g (P = 0.010), and for Abeta40 they were 37.8 ng/g and 29.8 ng/g (P = 0.067), respectively. Multiple regression analyses of the AD and control combined populations indicated that 1) muscle Abeta40 and muscle Abeta42 levels were correlated with each other (P < 0.001), 2) muscle Abeta40 levels were positively correlated with age (P = 0. 036), and 3) muscle Abeta42 levels were positively correlated with Braak stage (P = 0.042). Other forms of the Abeta peptide were discovered by mass spectrometry, revealing the presence of Abeta starting at residues 1, 6, 7, 9, 10, and 11 and ending at residues 40, 42, 44, 45, and 46. It is possible that in AD the skeletal muscle may contribute to the elevated plasma pool of Abeta and thus indirectly to the amyloid deposits of the brain parenchyma and cerebral blood vessels. The increased levels of Abeta in the temporalis muscles of AD patients suggest that alterations in AbetaPP and Abeta metabolism may be manifested in peripheral tissues.     

Controlled elimination of intracellular H(2)O(2): regulation of peroxiredoxin, catalase, and glutathione peroxidase via post-translational modification

The predominant enzymes responsible for elimination of hydrogen peroxide (H(2)O(2)) in cells are peroxiredoxins (Prxs), catalase, and glutathione peroxidases (GPxs). Evidence suggests that catalytic activities of certain isoforms of these H(2)O(2)-eliminating enzymes are extensively regulated via posttranslational modification. Prx I and Prx II become inactivated when phosphorylated on Thr(90) by cyclin B-dependent kinase Cdc2. In addition, the active-site cysteine of Prx I-IV undergoes a reversible sulfinylation (oxidation to cysteine sulfinic acid) in cells. Desulfinylation (reduction to cysteine) is achieved by a novel enzyme named sulfiredoxin. c-Abl and Arg nonreceptor protein tyrosine kinases associate with catalase in cells treated with H(2)O(2) by mechanisms involving the SH3 domains of the kinases and the Pro(293)PheAsnPro motif of catalase and activate catalase by phosphorylating it on Tyr(231) and Tyr(386). Similarily, GPx1 is activated by c-Abl- and Arg-mediated phosphorylation. The tyrosine phosphorylation is critical for ubiquitination-dependent degradation of catalase.     

Effects of behavior modification on body image, depression and body fat in obese Korean elementary school children

This study was performed to investigate the effects of behavior modification on body image, depression and body fat in obese elementary school children. Sixty-two elementary students of the 4th to 6th grade were selected from two different Seoul schools. Thirty-four children in one school were designated as the experimental group, and 28 children from the other school as the control group. The experimental group received 60 - 70 minutes of behavior modification, once a week, for 8 weeks. The control group received neither management nor treatment. The results indicated a significant improvement of body image and a reduction in the increase rate of body fat for the experimental group. This finding strongly supports the theory that behavior modification can be used as an effective strategy in the treatment of obese children.     

Rapid identification and susceptibility testing using the VITEK(R) 2 system using culture fluids from positive BacT/ALERT(R) blood cultures

BACKGROUND AND PURPOSE: In order to reduce the turnaround time for laboratory diagnosis of bacteremia, the efficacy of identification and antimicrobial susceptibility testing using samples taken directly from positive BacT/ALERT(R) standard aerobic and standard anaerobic blood culture bottles was evaluated. METHODS: 160 positive blood culture bottles were examined and incubated at 35 degrees C in 5% carbon dioxide for 4-24 h, and an aliquot of the culture fluid was Gram stained. Samples containing Gram-negative bacilli were inoculated on VITEK(R) 2 ID-GNB (identification-Gram-negative bacilli) and AST (antimicrobial susceptibility testing)-GN04 cards, and those containing Gram-positive cocci were inoculated on ID-GPC (identification-Gram-positive cocci) and AST-P526 cards. The same samples were also examined by the standard method, involving subculture from positive BacT/ALERT standard blood culture bottles. RESULTS: Eighty seven of 97 Gram-negative bacilli (89.7%) and 21 of 63 Gram-positive cocci (33.3%) were correctly identified to the species level. For antimicrobial susceptibility testing, the direct method had an overall error rate of 5.4% for Gram-negative bacilli, with 0.9% very major, 0.9% major, and 3.6% minor discrepancies compared to the standard method. The overall error rate in antimicrobial susceptibility testing for the 13 Staphylococcus spp. was 10.3%, with 6.0% very major, 2.6% major, and 1.7% minor discrepancies. CONCLUSION: These data suggest that VITEK 2 cards inoculated with samples taken directly from positive Bact/ALERT blood culture bottles would provide acceptable identification and antimicrobial susceptibility testing results for Gram-negative bacilli, but not for Gram-positive cocci. Compared to the standard method, the direct method would reduce turnaround time by at least 24 h.     

Characterization of an SAV organism and proposal of Mycobacterium triplex sp. nov.

Polyphasic taxonomic methods were employed to characterize a new species of slowly growing, nonpigmented mycobacteria. We propose the name Mycobacterium triplex sp. nov. for this new taxon. Conventional identification testing demonstrated a group of similar organisms that were geographically widespread in the United States. Commercially available nucleic-acid probes specific for the Mycobacterium avium complex were unreactive for these strains. High-performance liquid chromatography analysis of the mycolic acids revealed mycolate profiles that closely resembled Mycobacterium simiae. Comparative 16S rRNA sequence data confirmed the phylogenetic relationship of the strains with the slowly growing mycobacteria. Representative-type strains have been deposited in the American Type Culture Collection as strain ATCC 700071 [corrected].     

Sequence and chromosomal localization of two PET genes required for cytochrome c oxidase assembly in Saccharomyces cerevisiae

Summary The nuclear genes PET117 and PET191 are required for the assembly of active cytochrome c oxidase in S. cerevisiae, yet their gene products are not subunits of the final assembled cytochrome c oxidase complex. Plasmids bearing PET117 or PET191 were isolated by their ability to complement the pet117-1 or pet191-1 mutations, respectively. By restriction mapping, subcloning, and deletion analysis of yeast DNA fragments that complement these mutations, the PET117 and PET191 genes were localized to smaller regions of DNA, which were then sequenced from both strands. The PET117 open reading frame is of 107 codons and the PET191 open reading frame is of 108 codons. Neither the PET191 nor PET117 DNA sequences have been reported previously, and the derived amino-acid sequences of the PET191 and PET117 open reading frames exhibit no significant primary amino-acid sequence similarity to other protein sequences available in the NBRF data base, or from translated Genbank sequences. By hybridization of PET117 or PET191 probes first to a chromosome blot and next to a library of physically mapped fragments of yeast genomic DNA, the map locations of the PET191 and PET117 genes were determined. PET117 is located on chromosome V near the HIS1 gene and PET191 is located on chromosome X near the CYC1 gene.     

Anaemia and iron status among blood donors in a blood transfusion unit in Malaysia

Iron deficiency is a major complication of regular blood donation as a result of regular iron loss from each donated blood unit. Ninety-two regular blood donors and 95 first time blood donors attending a hospital-based blood transfusion centre were assessed as to their haematological and iron status by blood counts and serum ferritin levels as an indicator of iron stores. All donors had passed the haemoglobin-screening test using a copper sulphate method prior to blood donation. Ferritin levels were found to be significantly lower among regular blood donors (47.8 mmol/L) as compared to first time blood donors (94.2 mmol/L). Iron deficiency as observed by low ferritin levels was seen in 7.4% of all first time donors as compared to 17.4% in regular donors. Male first time donors showed a low prevalence of iron deficiency but the prevalence significantly increased with regular blood donation. Female first time and regular blood donors however did not show any significant differences in prevalence of iron deficiency, with both groups exhibiting prevalence rates similar to male regular donors. The association between haemoglobin levels and iron deficiency was poor and the copper sulphate-screening test was found insensitive to anaemia with many donors passing the test and donating blood despite being anaemic. It is concluded that a high prevalence of iron deficiency is present among regular male blood donors and all female donors. Besides, the use of the copper sulphate screening test as a sole criterion for anaemia screening should be reviewed. Ferritin measurements should be included in the routine assessment of blood donors especially among regular blood donors.