PCR-restriction fragment length polymorphism (RFLP) analyses reveal both extensive clonality and local genetic differences in Candida albicans

Using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to obtain genotypes for the diploid pathogenic yeast, Candida albicans, we analysed 204 C. albicans isolates from three populations of the Duke University community: two from clinical sources [one from patients infected with human immunodeficiency virus (HIV) and the other from patients without HIV infection], and the third from healthy student volunteers. The results indicated: (i) extensive evidence for clonality within and between populations of C. albicans; and (ii) greater genotypic and gene diversities in the nonclinical population than those derived from clinical specimens, regardless of HIV status. The two clinical populations were genetically more similar to each other than either was to the population consisting of isolates from healthy people. Within each population sample there was a general lack of heterozygotes, and random associations of alleles within and between loci were found in less than 50% of the loci or pairs of loci. These findings were consistent between the two sets of samples analysed: those including all isolates and those including only clone-corrected isolates. Possible mechanisms are presented to explain the observed patterns of genetic variation within and between C. albicans populations.     

A case of fatal pulmonary thromboembolism associated with the use of intravenous estrogen therapy

OBJECTIVE: To report a case of fatal pulmonary embolism associated with the use of i.v. estrogen therapy for menometrorrhagia. DESIGN: Case report. SETTING: University hospital. PATIENT(S): A 52-year-old woman with fibroid uterus treated with GnRH analogues with add-back therapy who presented with excessive vaginal bleeding. INTERVENTION(S): Intravenous conjugated estrogens were administered for a total of six doses. MAIN OUTCOME MEASURE(S): Fatal thromboembolic event. RESULT(S): The day after i.v. conjugated estrogens were administered, the patient had only scant vaginal bleeding, but she experienced the sudden onset of respiratory distress, became comatose, and subsequently had ventricular fibrillation leading to asystole. All resuscitative efforts failed. Postmortem examination revealed bilateral pulmonary artery thromboembolism (saddle embolus). CONCLUSION(S): Intravenous conjugated estrogen therapy may be complicated by fatal thromboembolic events. This potential adverse effect must be considered in the use of such therapy for severe menometrorrhagia, especially when treating a patient at increased risk.     

Sonographic findings in testicular sarcoidosis simulating malignant nodule

Testicular involvement by sarcoidosis is rare. We report a case of a patient with known sarcoid who had a unilateral testicular nodule with apparent capsular invasion on sonography. The epididymis was normal on both sides. Despite these atypical features, pathology showed the nodule to be a sarcoid granuloma. In patients with sarcoidosis, the differential diagnosis of an intratesticular mass should include testicular involvement by sarcoid.     

Features of the structure of carbon fibres used as filler for carbon-fibre-reinforced plastics

The structure of carbon fibres and filaments in carbon fabrics used as fillers for carbon-fibre-reinforced plastics was investigated. The basic characteristics of the pore structure of the carbon fillers were determined. It was found that the carbon fibres Uglen-9R “b”, Uglen-9R “c”, and Uglen-9R have sorption properties that can negatively affect the quality of carbon-fibre-reinforced plastic articles.     

Isoenzyme analysis of Arthrobotrys, a nematode-trapping fungus

Extraction and isoenzyme analysis of four isolates of Arthrobotrys including A. musiformis, A. robusta and A. conoides were conducted. Among the 14 enzymes studied by starch gel electrophoresis, using morpholine-citrate as gel/electrode buffer, the following nine enzymes showed interpretable banding patterns: alpha-esterase, fumarase, hexokinase, isocitrate dehydrogenase, leucine aminopeptidase, malate dehydrogenase, 6-phosphogluconate dehydrogenase, phosphoglucomutase and phosphoglucoisomerase. All isolates studied displayed typical isoenzyme phenotypes for each species. Two isolates of A. conoides differed in their alpha-isoesterase banding patterns, but no differences were observed for the other enzymes. The assay was satisfactory for enzyme extraction and resolution of Arthrobotrys and could be used in future taxonomic and genetic studies of this organism.     

Translating between orthogonally oriented stimulus and response arrays in four-choice reaction tasks

The human mineralocorticoid receptor (MR) is a member of the steroid-thyroid hormone receptor superfamily, which includes receptors for retinoic acid, vitamin D, and other steroids, such as the glucocorticoids (which bind the glucocorticoid receptor, GR). MR and GR, the corticosteroid receptors, share significant homology and are activated by steroid binding, resulting in a conformational change, nuclear translocation, and DNA binding. Despite these similarities with GR, the MR remains less well characterized. However, protein components known to be present in the unliganded GR are also likely to be components of the heteromeric MR complex. In the current study, we investigated whether or not hsp70, hsp90, and the immunophilin FKBP-52 are present in the nonsteroid-bound MR complex, because these proteins are known to be present in the unliganded GR complex. The unliganded MR complex was assembled in vitro using reticulocyte lysate and in vivo using the baculovirus overexpression system and Spodoptera frugiperda (Sf9) cells. Western blot analysis revealed the presence of hsp70, hsp90, and FKBP-52 in the unliganded complexes, but hsp90 and FKBP-52 were not detected following exposure to aldosterone. Electrophoretic mobility shift analysis demonstrated that DNA binding of MR occurred only after treatment with aldosterone. These studies indicate that proteins associated with the unliganded GR are also present in the unliganded MR complex, and that hsp90 and FKBP-52 dissociate prior to DNA binding in a manner similar to that described for GR. Finally, the stoichiometric analysis of the proteins present within the heteromeric MR complex suggests a divergence between this receptor and the GR.