The factor of magnification in mammography

The last generation of mammographic equipment allows mammography to be performed with direct magnification techniques, thanks to such technical features as microfocus, high focus-film distance, high-power generators. The authors compared the diagnostic yield of two different equipment sets, with 1.4x and 2x magnification respectively, and verified the utility of magnification radiography. A significant reduction was obtained in questionable diagnoses (42 to 18) in a group of 63 patients, with no evidence of substantial differences in the diagnostic yield of the images obtained with different magnification ratios. An objective analysis of the system resolution power privileges 2x magnification ratio, which however implies an increase in the average dose to the breast. The use of faster recording systems reduces the dose by 50%, though maintaining good image quality.     

Preliminary analysis of a randomized comparison of 5-fluorouracil versus 5-fluorouracil and high-dose continuous-infusion folinic acid in disseminated colorectal cancer

In this study, 50 patients were randomly assigned to treatment with 5-fluorouracil (FUra) or FUra plus high-dose continuous-infusion folinic acid. Five of 27 evaluable patients in the FUra group versus 10 of 21 patients in the FUra plus folinic acid arm of the study had objective partial remissions, P = 0.02. Time to progression was 3.9 months for FUra and 8.0 months for FUra and folinic acid, P = 0.006; however, median survivals (11.9 versus 14.5 months) were not different in this crossover study. Toxicity in both treatment arms was mild, although patients receiving FUra plus folinic acid experienced significantly more stomatitis than patients treated with FUra alone. This study suggests that high-dose, continuous-infusion folinic acid, which produces a steady-state level of biologically active folates of 10 microM, significantly increases the therapeutic activity of FUra.     

The relationship of the extrinsic blood supply to regeneration in graft reconstructed peripheral nerves

Median nerves of rats were reconstructed with conventional or vascular nerve grafts. After 2, 3 and 4 weeks, Allen Video-Enhanced Contrast, Differential Interference Contrast (AVEC-DIC) microscopy revealed axonal transport in most preparations, with varying degrees of myelination. Radio-isotope tracer was measured in the nerve. Two and 4 week measurements revealed no difference between the graft types. At 3 weeks the vascular graft group exhibited transport along the entire length of the nerve in contrast to a relatively abbreviated path length in the conventional graft group. Nerve conduction velocities (NCV) were measured proximal to, within and distal to the grafts. Three week NCV showed no difference between the graft types. The 4 week NCV revealed normal values in the vascular graft group at points distal to and within the graft. Significant slowing was seen in the conventional grafts at both points.     

Parental communication deviance: its relationship to parent, child, and family system variables

Audiotape recordings of family interaction samples from 30 nondistressed and 32 multiproblem families were coded for communication deviance (CD). Maternal CD was found to be higher in families high on measures of "preschizophrenic" child behavior, externalizing or "acting out" offspring behavior, overall family distress, and maladaptive marital and family alliance structures. Paternal CD was found to be higher in families in which offspring were rated high on externalizing behaviors.     

Prediction of rodent carcinogenicity utilizing a battery of in vitro and in vivo genotoxicity tests

The primary purpose of this study is to investigate the degree to which we can improve the prediction of rodent carcinogenicity (CA) by combining results from an in vitro and two in vivo genotoxicity tests. We used the Ames Salmonella assay (SAL) for the in vitro test and the micronucleus assay (MNC) and chromosome aberration assay (ABS) in mouse bone marrow cells for the two in vivo tests. We collected complete assay data for 82 chemicals (55 carcinogens and 27 noncarcinogens) from the NTP data base and the IARC monograph series. Our results indicate that: (1) only SAL affects the predictivity of CA, (2) MNC has a strong association with ABS, and (3) SAL predicts ABS. It has been known for some time that once the SAL assay result is available for prediction, other in vitro mutation tests provide little additional information for predicting CA. Our study indicates that the same conclusion holds for CA, SAL, MNC, and ABS.     

Polyomavirus BK DNA quantification assay to evaluate viral load in renal transplant recipients.

BACKGROUND: Several studies have disclosed a correlation between polyomavirus BK (BKV) and interstitial nephritis in renal transplant recipients and its quantification in urine and serum is therefore required to assess the role of BKV infection in nephropathy. OBJECTIVE: This paper describes a urine and serum BKV-DNA quantification protocol devised to evaluate the viral load. STUDY DESIGN: Screening of samples containing > or =10(3)/ml viral genome copies by a semi-quantitative polymerase chain reaction (PCR) assay is followed by precise quantification of the samples containing a high number of viral genomes in a quantitative-competitive (QC)-PCR assay. Generation of the competitor construct relied on the different sizes of wild-type and competitor amplicons. RESULTS AND CONCLUSIONS: Screening by semi-quantitative PCR selects samples with a high number of viral genomes for use in the more labor-intensive and -expensive QC-PCR assay and thus provides a handy means for quantitative DNA analysis of large numbers of samples. The results obtained in BKV-DNA quantification in urine and serum samples from 51 renal transplant recipients (22 on treatment with tacrolimus (FK506) and 29 on cyclosporine A (Cy A)) are interesting: BKV-DNA findings (43.1%) in urine samples are in agreement with the BKV urinary shedding reported in literature (5-45%). With regard to immunosuppressive treatment, the percentage of activation of the infection (revealed by BKV-DNA detection in urine samples) in the two groups of therapy is similar (40.9% vs 44.8%). The observation that the viral load in urine is dissociated with that of serum suggests that both parameters should be investigated in evaluation of the pathogenetic role of BKV reactivation in renal transplant recipients. Moreover, our BKV-DNA quantification protocol could be used to monitor viral load in urine and serum samples from renal transplant recipients so as to detect those at risk of nephropathy and monitor their response to immunosuppression reduction therapy if it occurs.     

Increased CSF F2-isoprostane concentration in probable AD

OBJECTIVE: To quantify F2-isoprostane levels in CSF obtained from the lumbar cistern of patients with AD, ALS, and controls. BACKGROUND: Studies of human postmortem tissue and experimental models have suggested a role for oxidative damage in the pathogenesis of several neurodegenerative diseases, especially AD and ALS. F2-isoprostanes are exclusive products of free-radical-mediated peroxidation of arachidonic acid that have been widely used as quantitative biomarkers of lipid peroxidation in vivo in humans. Recently, we showed that F2-isoprostane concentrations are significantly elevated in CSF obtained postmortem from the lateral ventricles of patients with definite AD compared with controls. METHODS: F2-isoprostanes were quantified by gas chromatography/negative ion chemical ionization mass spectrometry. RESULTS: CSF F2-isoprostanes were increased significantly in patients with probable AD, but not in ALS patients, compared with controls. CONCLUSIONS: Increased CSF F2-isoprostanes are not an inevitable consequence of neurodegeneration and suggest that increased brain oxidative damage may occur early in the course of AD.