Molecular screening of donor corneas for fungi before excision.

PURPOSE: To develop panfungal and Candida albicans species-specific polymerase chain reaction (PCR) assays to screen donor eyes for fungal contamination before corneal excision. METHODS: PCR primers were designed for either the broad-spectrum detection of fungal DNA or the specific detection of C. albicans DNA. Their sequences were based on rDNA regions highly conserved among and specific to fungi and C. albicans, respectively. PCR conditions with the two primer sets were optimized and tested for sensitivity using purified C. albicans genomic DNA and a plasmid containing the relevant region of C. albicans DNA. The specificity of the primer sets was established using higher eukaryotic, fungal, prokaryotic, and viral DNAs as PCR templates. Donor eye swab specimens were collected before corneal excision. DNA was extracted from the specimens and tested by both PCR assays. RESULTS: The lower limit of detection for both primer sets was consistently 10(3) genome equivalents, when using genomic DNA as a template and 10(2) copies of plasmid. The fungal PCR assay amplified DNA from all fungal species tested but did not amplify any of the selected mammalian, bacterial, or viral DNA. The C. albicans PCR detected the C. albicans DNA but was negative for all other DNA substrates, including the other fungal templates. Thirty-five percent of the donor eye samples tested were positive for fungus, and 19% were positive for C. albicans DNA. CONCLUSIONS: The PCR assays allowed the rapid screening of DNA extracted from specimens collected from corneal donors for potential fungal contamination. The assay was highly sensitive and specific for screening corneal surfaces. The results suggest that approximately one-third of donor eyes tested harbor fungi on the ocular surface.

Impact of gender and endothelin on renal vasodilation and hyperfiltration induced by relaxin in conscious rats.

Chronic administration of the hormone relaxin elicits renal vasodilation that is dependent on nitric oxide (NO) in both conscious intact and ovariectomized female rats. Our first objective was to test whether the hormone, when administered to approximate serum concentrations found in midterm pregnant rats, induces renal vasodilation in males. Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) increased significantly, on average, by 33 and 49% over baseline, respectively, after 5 days of recombinant human relaxin (rhRLX) administration to 12 conscious male rats by subcutaneous osmotic minipump. There were also significant decreases in hematocrit, plasma osmolality, and sodium concentration. Another objective was to determine whether endogenous endothelin (ET; via the endothelial ET(B) receptor) mediates the NO-dependent renal vasodilation produced by relaxin. rhRLX or vehicle was administered to conscious female rats (n = 9 and 8 rats, respectively). On the fifth day, baseline GFR and ERPF were both increased, on average, by 20-30% in the rats administered rhRLX (P < 0.05 vs. vehicle). Next, the specific ET(B)-receptor antagonist RES-701-1 was infused intravenously over 4 h in both groups of rats. In response to RES-701-1, there was a significant decline in both GFR and ERPF in the rats receiving rhRLX such that renal function converged in the two groups of animals. We conclude 1) relaxin induces marked changes in the renal circulation and in osmoregulation regardless of gender and 2) relaxin-induced renal vasodilation and hyperfiltration are mediated by endothelin through the endothelial ET(B) receptor subtype and NO.

Immune transfer protects severely immunosuppressed mice from murine cytomegalovirus retinitis and reduces the viral load in ocular tissue.

Cytomegalovirus (CMV) retinitis is a sight-threatening disease that affects immunosuppressed people and is prevalent in people with AIDS. The purpose of this study was to evaluate murine CMV (MCMV) retinitis in a replenishing model with adoptive immune transfer into severely immunosuppressed animals. Adult BALB/c mice, immunosuppressed with cyclophosphamide, were infected subretinally with 5x102 plaque-forming units of MCMV. Four to six hours later, 3-4x107 donor cells were transferred by intravenous infusion. Eight days after the transfer, the eyes that had received donor cells were studied histologically, titered for infectious virus, and analyzed with polymerase chain reaction (PCR). Adoptive transfer of total MCMV-immune lymph node (LN) cells or enriched LN lymphocytes specifically and significantly protected immunosuppressed mice from retinitis even after the initiation of infection. The transfer resulted in a reduced viral load, as measured by both plaque assay and PCR. This replenishment model will be useful for determining the specific immune parameters of protection from CMV retinitis.

Electrocardiographic radiotelemetry in the early recuperative period of acute myocardial infarction. Its value in detecting arrhythmias in the setting of a progressive coronary care unit.

One hundred seventeen consecutive patients with acute myocardial infarction transferred from the coronary care unit to a progressive coronary care unit were monitored by electrocardiographic radiotelemetry for a median of five days for arrhythmia detection. Eighty patients (68%) had arrhythmias; 37 patients (32%) had none. Almost all arrhythmias were detected by the sixth day of monitoring. Thirty-nine patients (33%) had premature ventricular contractions, two patients had primary ventricular tachycardia, one patient had primary ventricular fibrillation, and two patients had secondary ventricular fibrillation. An additional patient was successfully resuscitated after monitoring had been discontinued. Four (3%) of 117 patients had a potentially lethal arrhythmia treated successfully, three while being monitored. Twenty-five of the patients (21%) had 33 episodes of treatment intervention because of telemetrically detected events. Five patients (4%) died, all of unpreventable causes. No patient died because of an arrythmia. We conclude that telemetry is feasible and practical in detecting arrhythmias. It is clear that potentially fatal ventricular arrhythmias do occur following transfer from the coronary care unit and that monitoring is, therefore, desirable.