Neurobehavioral phenotype in carriers of the fragile X premutation

There have been contradictory findings in the fragile X (fraX) literature about possible neurocognitive and psychological symptoms due to the fraX premutation (pM). The purpose of the present study was to investigate the relationship between CGG repeat length and neurobehavioral functioning in carriers of the fraX pM. Eighty‐five female carriers of the pM with allele sizes ranging from 59–166 were administered a comprehensive IQ test (WAIS‐III) and completed a questionnaire designed to measure psychopathology (Symptom Checklist (SCL)‐90‐R). No relationship between allele size and cognition was identified. A significant negative relationship between allele size and age was found, as well as a positive relationship between allele size and depression. Follow‐up analyses separating small and large allele sizes (below and above 100 CGG repeats) indicated that individuals with larger allele sizes scored significantly higher on the Interpersonal Sensitivity and Depression subscales of the SCL‐90‐R. Despite the limitation of few individuals with high CGG repeat lengths, our findings suggest that females with larger premutated alleles (≥ 100 repeats) display some clinical manifestations of fraX syndrome. © 2001 Wiley‐Liss, Inc.     

Evaluation of the harmonized alert sensing technology device for hemodynamic monitoring in chronic hemodialysis patients

The Harmonized Alert Sensing Technology (HASTE) device was developed to overcome the primary shortcomings of interval based noninvasive blood pressure (BP) monitoring. This study was conducted to assess the reliability of the HASTE system compared with standard cuff BP values in patients on hemodialysis. A total of 1,370 HASTE measurements were compared with oscillometric standard cuff systolic BP values in 42 sessions of 15 patients on hemodialysis. The average discrepancy between the HASTE and cuff systolic BP was 1.41 +/- 16.90 mm Hg. Compared with cuff measurements, 31% of systolic BP fell within a range of 5 mm Hg difference, 57% of systolic BP fell within 10 mm Hg, and 73% of systolic BP fell within a 15 mm Hg band. According to British Hypertension Society standards or Association for the Advancement of Medical Instrumentation criteria, the current HASTE method did not perform well. Technology to provide noninvasive hemodynamic monitoring is, however, in its developmental stage. The effort at continuous systolic pressure monitoring using existing, readily available, and frequently used techniques is exciting. Although the HASTE system as currently configured and calibrated did not adequately perform, variations in site analysis and conversion factors may increase pressure sensitivity and tracking over the course of a standard dialysis treatment.     

Dielectrophoretic assay of bacterial resistance to antibiotics

The dielectrophoretic collection spectra of antibiotic-sensitive and antibiotic-resistant strains of Staphylococcus epidermidis have been determined. These indicate that in the absence of antibiotic treatment there is a strong similarity between the dielectric properties of sensitive and resistant strains, and that there is a significant difference between the sensitive strains before and after treatment with the antibiotic streptomycin after 24 h exposure. This method offers possibilities for the assessment of bacterial resistance to antibiotics.     

Methodological aspects of DNA image cytometry in formalin-fixed paraffin-embedded material from pancreatic adenocarcinoma

Deparaffinized and disintegrated material from conventionally formalin-fixed and paraffin-embedded surgical specimens of 100 cases of ductal adenocarcinoma of the pancreas was Feulgen-stained, and the cytochemical DNA distribution patterns of at least 100 single tumour cells and 50 "control" cells (fibrocytes) were assessed by means of image cytometry (ICM). In 77 cases a sufficient number of neoplastic cells could be obtained for these DNA assessments. The fairly high number (23) of cases that had to be excluded due to too small amounts of disintegrated cells or cell nuclei may be explained by the high content of connective tissue stroma in these pancreatic adenocarcinomas. The tumour cell nuclei in 76 of these 77 cases showed cytochemically a clear-cut "non-diploid" DNA distribution pattern. This observation reflects the well-known highly malignant growth potential of this carcinoma. Despite the fact that about 1/4 of the tumours had to be excluded, the main result of our methodological study is, after all that conventionally formalin-fixed paraffin-embedded specimens of most pancreatic adenocarcinomas can be successfully used for the deparaffinization-disintegration procedure preceding the nuclear DNA assessments by means of ICM. Additional studies are, however, required to obtain the diagnostic and prognostic impact of the results of such cytochemical analyses of the DNA distribution pattern in adenocarcinomas of the pancreas.     

Distribution of a formalin-resistant myelomonocytic antigen (L1) in human tissues. II. Normal and aberrant occurrence in various epithelia

L1 is an approximately 36-kd protein present in virtually all resting peripheral blood neutrophils and monocytes. It is particularly well preserved in formalin-fixed and paraffin-embedded routine material. In a recent immunohistochemical study, the authors showed that L1 has a restricted distribution within the monocyte-derived cell lineage, being mainly confined to reactive histiocytes (infiltrating macrophages). A protein sharing physicochemical and antigenic properties with L1 was identified in extracts of epidermal scales obtained from patients with psoriasis. This epithelial L1 was generally not expressed by normal epidermis, but its production was abundant in several skin diseases. Moreover, mucosal squamous epithelium normally expressed L1. No other epithelia showed signs of L1 production, although occasional patchy uptake was indicated, particularly in kidney tubular epithelium.     

Estimation of the rate of unrecognized cross-contamination with mycobacterium tuberculosis in London microbiology laboratories

Isolates from patients with confirmed tuberculosis from London were collected over 2.5 years between 1995 and 1997. Restriction fragment length polymorphism (RFLP) analysis was performed by the international standard technique as part of a multicenter epidemiological study. A total of 2,779 samples representing 2,500 individual patients from 56 laboratories were examined. Analysis of these samples revealed a laboratory cross-contamination rate of between 0.54%, when only presumed cases of cross-contamination were considered, and 0.93%, when presumed and possible cases were counted. Previous studies suggest an extremely wide range of laboratory cross-contamination rates of between 0.1 and 65%. These data indicate that laboratory cross-contamination has not been a common problem in routine practice in the London area, but in several incidents patients did receive full courses of therapy that were probably unnecessary.     

CORTICAL SLOW POTENTIAL CHANGES IN MAN RELATED TO INTERSTIMULUS INTERVAL AND TO PRE TRIAL PREDICTION OF INTERSTIMULUS INTERVAL

Two experiments were performed to explore further the relationship between the cortical slow potential change known as the “contingent negative variation” (CNV) and the concept of “expectancy.” In Experiment I, 24 male Ss were presented click pairs, with inter-click intervals of 800, 1600 and 4800 msec (2 blocks of 10 trials each, counterbalanced between Ss for order), and instructed to press a key after the second click. Interval by order by trials analysis of variance showed interval to be the only significant factor: CNVs were lower and RTs longer as interval increased. In Experiment II, 8 female Ss given 60 pairs of clicks, 30 each with separations of 1200 and 2400 msec, were instructed to respond as in Experiment I, and were asked to make a pretrial prediction of the interval they would next receive. Analysis of variance of RTs showed that Ss responded slower when the interval was other than that predicted. Prediction by reception by subjects analysis of variance of CNV amplitude at the 1200 msec point gave a significant F only for prediction, mean amplitude for short being higher than for long. A similar design applied to CNV amplitudes at both the 1200 and 2400 msec points when Ss received the long interval yielded a significant measurement point by interval predicted interaction; at the 1200 msec point, short predictions were followed by higher CNVs than were long predictions; at 2400 msec, the opposite was found. These data combine with those already in the literature to indicate that the relationship between “expectancy” and the CNV is far from simple, and that cognitive and motivational factors play a significant role in determining CNV amplitude.     

Molecular analysis of <Emphasis Type="Italic">Fiji disease virus</Emphasis> genome segments 5, 6, 8 and 10

Summary. The complete sequences of Fiji disease virus (FDV) genome segments 5 (S5), S6, S8 and S10 were obtained and comprised 3150nt, 2831nt, 1959nt and 1819nt, respectively. Each segment contained a single ORF which encoded putative proteins of 115kDa, 97kDa, 69kDa and 63.0kDa, respectively. The putative amino acid sequences encoded by S5 and S6 contained putative leucine zipper motifs while FDV S5 and S8 each contained an ATP-GTP-binding motif. At the amino acid level, FDV S5, S6, S8 and S10 showed most similarity to the corresponding segments of Rice black-streaked dwarf virus. Based on sequence similarities, it is predicted that FDV S8 encodes a minor core protein, while FDV S10 encodes an outer capsid protein. The evolutionary relationships of FDV to other reoviruses are discussed.The nucleotide sequence data for FDV S5, S6, S8 and S10 are available in the DDBJ/EMBL/GenBank databases under the accession numbers AY029521, AF356083, AY297693 and AY297694, respectively.