Intestinal Coccidiosis in a Patient with Alpha-chain Disease

During an ultrastructural study of small-intestinal mucosa from a patient suffering from alpha-chain disease organisms were identified within the epithelial cytoplasm which showed the fine structural features of the coccidian group. Though coccidiosis is well recognized as causing a diarrhoeal and often lethal illness in animals it has been neglected as a cause of disease in man. Thus this finding may be significant and warrants further investigation into its possible role in the pathogenesis of alpha-chain disease.     

Typing of Genetic Markers Involved in Stress Response by Fluorescent cDNA-Amplified Fragment Length Polymorphism Technique

Identification of genetic markers involved in stress response to physical factors or chemical substances in organisms is a challenging task. Typing of upregulated gene expression due to selective antibacterial pressure is a promising approach in the search of molecular mechanisms responsible for development of resistance. cDNA-Fluorescent Amplified Fragment Length Polymorphism (cDNA-FAFLP) strategy was developed and applied in the search of antimycotic drug resistance marker(s) in medically important fungi as an alternative method to microarray analysis. We compared differential gene expression of two sensitive Candida albicans reference strains (ATCC 10231 and ATCC 60133) and two of their paired resistant to fluconazole and itraconazole mutants. Resistant mutants Candida albicans FLC-R, resistant to fluconazole (MIC > 128 μg/ml) and Candida albicans ICZ-R, resistant to itraconazole (MIC > 4 μg/ml) were obtained in subcultures with gradual increase of the antifungal in the culture medium. cDNA-AFLP profile in both itraconazole resistant mutants showed specific spectrophotometric peaks with 5–6-fold RNA overexpression product of 500 bp length compared to the sensitive strains. Fluconazole mutants do not reveal RNA level changes under tested by us typing conditions. These results indicate that the cDNA-FAFLP strategy is a relatively rapid, simple, and reliable method for simultaneous typing of both constitutive and induced differences in expression of host genes providing insight into the biological processes involved in response to drugs in bacteria and fungi. Moreover, this methodology could be tested for typing of the genome response of any organism to physical or chemical stress factors.     

Effect of pathogenic mutations on the structure and dynamics of Alzheimer’s Aβ42-amyloid oligomers

Converging lines of evidence suggest that soluble Aβ-amyloid oligomers play a pivotal role in the pathogenesis of Alzheimer’s disease, and present direct effectors of synaptic and cognitive dysfunction. Three pathological E22-Aβ-amyloid point mutants (E22G, E22K, E22Q) and the deletion mutant E22Δ exhibit an enhanced tendency to form prefibrillar aggregates. The present study assessed the effect of these four mutations using molecular dynamics simulations and subsequent structural and energetic analyses. Our data shows that E22 plays a unique role in wild type Aβ, since it has a destabilising effect on the oligomer structure due to electrostatic repulsion between adjacent E22 side chains. Mutations in which E22 is replaced by an uncharged residue result in higher oligomer stability. This effect is also observed to a lesser extent for the E22K mutation and is consistent with its lower pathogenicity compared to other mutants. Interestingly, deletion of E22 does not destroy the amyloid fold but is compensated by local changes in the backbone geometry that allow the preservation of a structurally important salt bridge. The finding that all mutant oligomers investigated exhibit higher internal stability than the wild type offers an explanation for the experimentally observed enhanced oligomer formation and stability.     

Chest-wall deformity after tissue expansion for breast reconstruction

A prospective longitudinal study of chest-wall deformity after tissue expansion for breast reconstruction was performed in 19 women. CT imaging was a sensitive method for detecting occult deformity. Using a semiquantitative scale for measuring deformity, all patients and 94 percent of expanders had some thoracic abnormality after tissue expansion. Rib and chest-wall contour changes were observed under 81 and 68 percent of the expanders, respectively. Routine chest roentgenograms were not a sensitive method for evaluating these deformities. The magnitude of deformity after unilateral expansion was not significantly different from that after bilateral expansion. Linear regression analysis indicated that early periprosthetic capsular contracture was negatively correlated with chest wall deformity. Only one patient experienced a clinically noticeable complication from chest compression--transient postexpansion exertional dyspnea. After removing the expanders and placing permanent implants along with capsulotomy, the mean deformity index decreased by 57 percent after 10.5 months median follow-up, which was highly significant (p less than 0.001). Our findings suggest that chest-wall deformity is a common occurrence after tissue expansion in patients undergoing breast reconstruction and is usually of minor clinical significance.     

A phytoecological study of the mire Northern Kisselbergmosen, SE Norway. II. Identification of gradients by detrended (canonical) correspondence analysis

The vegetation of a poor mire is sampled by two procedures; 800 randomly placed sample plots made up the R data set, 765 subjectively selected plots in 153 sample plot series made up the S data set. DCA ordination and constrained ordination by DCCA of the data sets and subsets showed the existence of three coenoclines in the material: (1) the coenocline along the mire expanse: low to high median depth to the water table—mire margin gradient, (2) the poor-rich coenocline, dependent on a complex-gradient in substrate chemistry, and (3) a coenocline attributed to variation in peat productivity. Thus the assumption of Fennoscandian mire scientists embedded in numerous systems for classifying mire vegetation, that three gradients are the most important in the mire ecosystem, is partly confirmed. In the investigated area, two of the gradients normally considered make up one complex coenocline (1), and a fourth coenocline (3) has to be added. The effects of sampling techniques on correlations between coenoclines and on ordination results are discussed, and an improved sampling technique is suggested. The major faults of DCA: (1) the tongue effect, and (2) the instability, are described and discussed. It is concluded that if due attention is taken to reveal effects of the faults of the method, DCA is among the best ordination methods currently available.     

Radiology services for remote communities: cost minimisation study of telemedicine.

OBJECTIVES--To determine the social costs of providing a rural population with radiology services under three different systems: the existing system (a small x ray unit at the remote site and all other examinations at the nearest radiology department (the host site)); a teleradiology system (most examinations at the remote site and more advanced examinations at the host site); and all examinations at the host site. DESIGN--Cost minimisation study. SETTING--Primary health care in a remote community in Norway. SUBJECTS--A randomly selected sample (n = 597) of all patients (n = 1793) having radiological examinations in 1993. MAIN OUTCOME MEASURES--Annual direct medical costs, direct non-medical (travel) costs, and indirect costs (lost production) of the three options. RESULTS--After exclusion of costs common to the three systems the direct medical, direct non-medical, and indirect costs of the three options were, respectively, 9000 pounds, 51,000 pounds, and 31,500 pounds (total 91,500 pounds) for the existing system; 108,000 pounds, 2,000 pounds, and 13,500 pounds (total 123,500 pounds) for the teleradiology option; and 0 pounds, 75,000 pounds, and 42,000 pounds (117,000 pounds in total) for the "all at host" option. Sensitivity analyses indicated that the existing system is the least costly option except when lost leisure is valued as highly as lost production. CONCLUSION--The teleradiology option did not seem to be cost saving in the study community. Such systems, however, may be justified on the grounds of equity of access and quality of care.     

Plasmids and serotypes of hemolytic fecalEscherichia coli

Twelve of 21 human, hemolytic, fecal isolates ofEscherichia coli produced type 1 hemolysin (HLY1), an extracellular, heat-labile molecule (alpha-hemolysin). Although no common plasmid species was apparent, 11 of 12 HLY1 strains possessed a plasmid60 megadaltons (Mdal); 5 of 9 strains with other hemolysins possessed a plasmid of comparable molecular mass (Fisher's exact probability=0.0805). One derivative of an HLY1+strain, which contained a 125 Mdal plasmid, no longer expressed HLY1 and contained a single 102 Mdal plasmid. The presence of large plasmids of varying size and an apparent deletion mutation in HLY1 strains suggest that HLY1 determinants are located on a small, unstable genetic element. In an initial survey of 224 human fecal isolates ofE. coli, the predominant hemolytic serotype was 06:H-, and conversely most (85%) 06:H-isolates were HLY1+. Serotype appears to play an important role in HLY1 expression.