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C Downs

Publications and source records attributed to C Downs.

13 recordsLinked to original sources

Preliminary examination of short-term cellular toxicological responses of the coral Madracis mirabilis to acute Irgarol 1051 exposure.

Irgarol 1051 is an s-triazine herbicide formulated with Cu2O in antifouling paints. Recent studies have shown that Irgarol 1051 inhibits coral photosynthesis at environmentally relevant concentrations, consistent with its mode of action as a photosystem II inhibitor. Related toxicologic effects of this herbicide on coral cellular physiology have not yet been investigated. We used cellular diagnostics to measure changes in 18 toxicologic cellular parameters in endosymbiotic algal (dinoflagellate) and cnidarian (host) fractions of the common branching coral Madracis mirabilis associated with in vivo 8- and 24-hour exposures to a nominal initial Irgarol 1051 concentration of 10 microg L(-1). Responses measured were (1) xenobiotic response, which includes total and dinoflagellate multixenobiotic resistance (MXR), cnidarian cytochrome (CYP) P450-3 and P450-6 classes, cnidarian, and dinoflagellate glutathione-s-transferase (GST); (2) oxidative damage and response, which includes cnidarian and dinoflagellate Cu/Zn and Mn superoxide dismutase (SOD), cnidarian and dinoflagellate glutathione peroxidase (GPx), cnidarian catalase, and total protein carbonyl); (3) metabolic homeostasis, which includes chloroplast and invertebrate small heat-shock proteins (sHsp), cnidarian protoporphyrinogen oxidase IX (PPO), cnidarian ferrochelatase, and cnidarian heme oxygenase; and (4) protein metabolic condition, which includes cnidarian and dinoflagellate heat shock proteins (hsp70 and hsp60), total ubiquitin, and cnidarian ubiquitin ligase. Acute responses to Irgarol 1051 exposure included significant increases in total and dinoflagellate MXR, dinoflagellate Cu/Zn SOD, dinoflagellate chloroplast sHsp, and cnidarian PPO. Irgarol 1051 exposure resulted in decreases in cnidarian GPx, cnidarian ferrochelatase, cnidarian catalase, and cnidarian CYP 450-3 and -6 classes. Related implications of Irgarol 1051 exposure to coral cellular condition are discussed.

Animals↗

Patient education for discharge after coronary bypass surgery in the 1990s: are patients adequately prepared?

Short hospitalizations for patients undergoing coronary artery bypass grafting (CABG) require continuous nursing evaluation of patients' discharge education. Six institutions collaborated in surveying 300 postoperative patients with CABG to identify learning priorities and patients' perceptions of the effectiveness of discharge education. Data analysis from the self-administered questionnaire demonstrated consistent patient priorities across institutions. Differences in teaching methods and content did not affect perceived preparedness or importance scores. Regional experience demonstrates that variable teaching efforts meet patients' priorities and provide high overall patient preparedness for discharge. Patients with the shortest hospitalizations had higher preparedness scores.

Adult↗

Familial Mondini dysplasia.

OBJECTIVES/HYPOTHESIS: To determine the mode of inheritance of familial nonsyndromic Mondini dysplasia. STUDY DESIGN: Correlative clinical genetic analysis of a single kindred. METHODS: Clinical history, physical examination, audiologic analysis, computed tomography of the temporal bones, and cytogenetic analysis. RESULTS: The male proband, three affected sisters, and an affected brother are offspring of unaffected parents. The mother and an unaffected brother have audiologic findings suggestive of heterozygous carrier status for a recessive hearing loss gene. CONCLUSIONS: Pedigree analysis indicates autosomal recessive inheritance in this family. The observed inheritance and clinical, audiologic, and radiologic findings are different from those previously described for another family with nonsyndromic Mondini dysplasia. The phenotype in this study family therefore represents a distinct subtype, indicating clinical and genetic heterogeneity of this disorder. This information should facilitate future molecular linkage analyses and genetic counselling of patients with inner ear malformations.

Adult↗

Familial large vestibular aqueduct syndrome.

The large vestibular aqueduct syndrome (LVAS) is a distinct clinical entity characterized by stepwise progressive sensorineural hearing loss associated with isolated enlargement of the vestibular aqueduct. A correlative clinical, audiologic, vestibular, cytogenetic, and radiographic analysis of a family with inherited LVAS was performed. The male proband and his affected brother are offspring of unaffected parents, and have no other abnormalities. Pedigree analysis suggests autosomal recessive or X-linked inheritance with variable expressivity of LVAS in this family. This study is the first description of familial inheritance of LVAS. LVAS may account for a significant number of patients with nonsyndromal, genetic sensorineural hearing loss. Future molecular analyses of this study family may identify the causative gene(s) in LVAS.

Adult↗

Sleep and suicidality in psychotic patients.

The purpose of the study was to determine whether polysomnographic rapid eye movement (REM) sleep parameters distinguish between psychotic patients with and without a history of suicidal behavior. We examined both hand-scored and automated measures of rapid eye movement (REM) sleep in psychotic patients with and without a history of suicidal ideation or attempts. Patients with suicidal behavior had significantly increased REM activity and time both in the whole night data and in the first REM period. These findings suggest an association between REM sleep abnormalities and suicidal behavior, perhaps related to alteration in serotonergic function.

Adult↗