Epidemiology of Aeromonas species in a hospital

The occurrence of Aeromonas spp. in a hospital water supply, in patients and in the local community was investigated. In healthy persons outside the hospital the isolation rate was 3.6% and among hospital patients it was 6%. Seven per cent of water samples yielded Aeromonas strains. Isolates were typed by sodium dodecyl sulphate polyacrylamide gel electrophoresis of sulphur-35 methionine labelled proteins of Aeromonas isolates. No relationship between water and human isolates could be established, even when a strain of A. hydrophila producing Vero cell cytotoxin contaminated enteral feeds given to patients in the intensive care unit.     

Loss of Chromosome 17 loci in prostate cancer detected by polymerase chain reaction quantitation of allelic markers

Using a polymerase chain reaction/microsatellite marker system, we demonstrated that 6 of 22 (27%) clinical stage B (early) primary prostate tumors showed loss of heterozygosity at one or more of five loci on chromosome 17. The sensitivity of this study was increased by use of a Phosphorlmager and statistical analysis of replicate tumor-normal DNA pairs. Two patients showed tumor-specific interstitial loss at a locus in close proximity to the familial breast cancer gene BRCAI. These findings suggest that genes on the proximal long arm of chromosome I7 play a pivotal role in the early development of at least a subset of prostatic tumors. © 1995 Wiley-Liss, Inc.     

A simple method for PCR based analyses of immunohistochemically stained, microdissected, formalin fixed, paraffin wax embedded material.

Microdissection was performed on sections cut from formalin fixed, paraffin wax embedded archival material, which had been subjected to conventional immunohistochemistry. Crude DNA extracts, which were obtained from these microdissected samples by a simple microwave step, were then added directly to amplification reactions. Analyses using a range of polymerase chain reaction (PCR) based techniques, including microsatellite repeat polymorphism analysis at the NM23-H1 locus and sequencing of exons 5, 7, and 8 of the p53 gene, were performed successfully. Universal PCR amplification was also carried out on the microdissected material and probes suitable for use in comparative genomic hybridisation (CGH) were obtained in all cases. This technique will enable a range of effective genetic analyses to be carried out on specific subsets of cells that have been characterised previously by immunohistochemistry.     

Longitudinal trajectory of Amyloid‐related hippocampal subfield atrophy in nondemented elderly

Hippocampal atrophy and abnormal β‐Amyloid (Aβ) deposition are established markers of Alzheimer's disease (AD). Nonetheless, longitudinal trajectory of Aβ‐associated hippocampal subfield atrophy prior to dementia remains unclear. We hypothesized that elevated Aβ correlated with longitudinal subfield atrophy selectively in no cognitive impairment (NCI), spreading to other subfields in mild cognitive impairment (MCI). We analyzed data from two independent longitudinal cohorts of nondemented elderly, including global PET‐Aβ in AD‐vulnerable cortical regions and longitudinal subfield volumes quantified with a novel auto‐segmentation method (FreeSurfer v.6.0). Moreover, we investigated associations of Aβ‐related progressive subfield atrophy with memory decline. Across both datasets, we found a converging pattern that higher Aβ correlated with faster CA1 volume decline in NCI. This pattern spread to other hippocampal subfields in MCI group, correlating with memory decline. Our results for the first time suggest a longitudinal focal‐to‐widespread trajectory of Aβ‐associated hippocampal subfield atrophy over disease progression in nondemented elderly.     

Familial hypercholesterolemia in Utah kindred with novel 2412-6 Ins G mutations in exon 17 of the LDL receptor gene

Familial hypercholesterolemia (FH) is a monogenic disorder associated with primary hypercholesterolemia. FH is characterized by autosomal co-dominant inheritance with strikingly elevated LDL-cholesterol, the presence of xanthoma and premature atherosclerosis. In the course of investigations of coronary artery disease in Utah, we identified a family whose proband showed elevated plasma levels of LDL cholesterol. To determine the genetic etiology of the lipoprotein abnormalities, we screened DNA samples from the family for mutations in all 18 exons and the exon- intron boundaries of the low-density lipoprotein receptor (LDLR) gene. Novel point mutations were identified in the proband: a one-base insertion of G to a five-G stretch at nucleotides 2412-6 (codons 783-785), causing a frameshift in exon 17 of the LDL receptor gene. The direct sequencing method was used to examine six members of the family recruited for the diagnosis. This method helped to unequivocally diagnose the five individuals as heterozygous for this particular LDL receptor mutation. This method also helped us to diagnose with FH, or to exclude from carrier status, three children between ages 6 and 11.