PubMed Health⌕ Search

Biomedical subjects

R A Duncan

Publications and source records attributed to R A Duncan.

At least 19 recordsLinked to original sources
PubMed2006

Contact burns from hair straighteners: a new hazard in the home.

This series highlights a previously unreported hazard for children within the home, hair straightening irons. Thermal injury is a common reason for presentation at the emergency department. Contact burns from domestic irons and hair curling tongs are well documented in the literature. We have become aware of this new hazard in the home, which has resulted in several presentations to our department with deep partial thickness or full thickness burns.

Arm Injuries↗
PubMed2006

Sedation practice in a Scottish teaching hospital emergency department.

OBJECTIVES: To conduct a prospective survey in a teaching hospital emergency department to evaluate performance according to safe sedation principles, to establish the demographics of those sedated, and to review the drugs used and doses given to patients in the department. Any adverse events were reviewed for identification of preventable causes. METHODS: Pre-sedation checklists, peri-procedural observations, and patient notes were reviewed for 101 cases from 4 December 2004 to 3 September 2005. There are departmental guidelines outlining the principles of safe sedation. RESULTS: Emergency department procedural sedation was performed for a variety of acute conditions in patients aged from 7 to 91 years old. A variety of sedation agents were administered, morphine and midazolam being used most frequently. Drug administration, maximum sedation level, and time to recovery and discharge were recorded. Four adverse events were reported, none of which were clinically significant. Departmental guidelines were followed. CONCLUSION: Emergency department sedation is a safe and effective procedure if appropriately trained practitioners follow the principles of safe sedation.

Adolescent↗
PubMed1998

Response of lymphoepithelial parotid cysts to antiretroviral treatment in HIV-infected adults.

BACKGROUND: Surgical resection has been the usual therapy for HIV-infected patients with lymphoepithelial parotid cysts. OBJECTIVE: To study antiretroviral therapy for lymphoepithelial parotid cysts. DESIGN: Case series. SETTING: HIV outpatient clinics. PATIENTS: HIV-infected patients with lymphoepithelial parotid cysts. INTERVENTION: Antiretroviral therapy. MEASUREMENTS: Change in size of the parotid cyst, CD4 lymphocyte count, and HIV viral load. RESULTS: Nine HIV-infected adults presented with chronic, large parotid cysts, eight of which were bilateral. In at least seven patients, the cysts were the initial sign of HIV infection. In six patients, the cysts resolved completely with combination antiretroviral therapy. Four of these patients also received prednisone. Three patients who did not comply with antiretroviral therapy had partial responses followed by relapses. CONCLUSIONS: Parotid cysts are an unrecognized sign of early HIV infection. These cysts respond to combination antiretroviral therapy, with or without corticosteroids. Surgical resection should be reserved for patients in whom medical therapy has failed or those who refuse or are poorly compliant with medical therapy.

Adult↗
PubMed1997

Society for Healthcare Epidemiology of America and Infectious Diseases Society of America Joint Committee on the Prevention of Antimicrobial Resistance: guidelines for the prevention of antimicrobial resistance in hospitals.

Antimicrobial resistance results in increased morbidity, mortality, and costs of health care. Prevention of the emergence of resistance and the dissemination of resistant microorganisms will reduce these adverse effects and their attendant costs. Appropriate antimicrobial stewardship that includes optimal selection, dose, and duration of treatment, as well as control of antibiotic use, will prevent or slow the emergence of resistance among microorganisms. A comprehensively applied infection control program will interdict the dissemination of resistant strains.

Anti-Bacterial Agents↗
PubMed1997

Controlling use of antimicrobial agents.

Physicians and hospitals must curtail the excessive use of antimicrobial agents to limit the emergence and spread of multiply resistant organisms. This article describes how to organize an antimicrobial control program and provides options for hospitals working with a range of resources.

Anti-Infective Agents↗
PubMed1997

Society for Healthcare Epidemiology of America and Infectious Diseases Society of America Joint Committee on the Prevention of Antimicrobial Resistance: guidelines for the prevention of antimicrobial resistance in hospitals.

Antimicrobial resistance results in increased morbidity, mortality, and costs of health care. Prevention of the emergence of resistance and the dissemination of resistant microorganisms will reduce these adverse effects and their attendant costs. Appropriate antimicrobial stewardship that includes optimal selection, dose, and duration of treatment, as well as control of antibiotic use, will prevent or slow the emergence of resistance among microorganisms. A comprehensively applied infection control program will interdict the dissemination of resistant strains.

Anti-Bacterial Agents↗
PubMed1993

Idiopathic CD4+ T-lymphocytopenia--four patients with opportunistic infections and no evidence of HIV infection.

BACKGROUND AND METHODS: We describe four patients without major risk factors for human immunodeficiency virus (HIV) infection, each of whom presented with severe opportunistic infections and was found to have idiopathic CD4+ T-lymphocytopenia. We performed assays to detect the presence of retroviruses and undertook immunophenotyping of subgroups of peripheral-blood lymphocytes. RESULTS: The opportunistic infections at presentation included Pneumocystis carinii pneumonia, cryptococcal meningitis (two patients, one with concurrent pulmonary tuberculosis), and histoplasma-induced brain abscess. During 10 to 68 months of observation, none of the four patients had evidence of infection with HIV type 1 or 2 or human T-cell lymphotropic virus type I or II on the basis of epidemiologic, serologic, or polymerase-chain-reaction studies or culture, nor was there any detectable reverse transcriptase activity. Although all the patients had severe, persistent CD4+ T-lymphocytopenia (range, 12 to 293 cells per cubic millimeter), the CD4+ cell count progressively declined in only one and was accompanied by multiple opportunistic infections. All four patients had significantly reduced numbers of circulating CD8+ T cells, natural killer cells, or B cells (or all three). CONCLUSIONS: These four patients had idiopathic CD4+ T-lymphocytopenia with opportunistic infections but no evidence of HIV infection. Instead of the progressive, selective depletion of CD4+ T cells characteristic of HIV infection, some patients with idiopathic immunodeficiency have stable CD4+ cell counts accompanied by reductions in the levels of several other lymphocyte subgroups.

Adult↗
PubMed1993

Selective decontamination of the digestive tract: risks outweigh benefits for intensive care unit patients.

Selective decontamination of the digestive tract (SDD) involves the administration of non-absorbable antibiotics (+/- a systemic antibiotic) to prevent colonization and infection in intensive care unit patients. The regimen is targeted at nosocomial gram-negative bacilli, some gram-positive bacteria and yeast. Although all studies of SDD have demonstrated reduced rates of bacterial colonization and most yielded lower respiratory tract infection, it is unclear if the major impact of SDD is on pneumonia or tracheobronchitis. SDD regimens utilizing a broad spectrum, systemic antibiotic appear to be more effective, suggesting that this constitutes early treatment rather than prophylaxis. To date, there is conflicting evidence that SDD significantly reduces length of stay, mortality, or hospital costs. Currently, there are concerns that SDD may result in increased colonization and infection with gram-positive organisms and multi-drug resistant pathogens, particularly in medical ICU patients or when used for extended periods of time.

Anti-Bacterial Agents↗
PubMed1992

A multistate outbreak of sporotrichosis associated with sphagnum moss.

In the spring of 1988, the largest documented US outbreak of cutaneous sporotrichosis to date occurred, with 84 cases among persons from 15 states who were exposed to Wisconsin-grown sphagnum moss used in packing evergreen tree seedlings. In New York State, 13 cases occurred among 109 forestry workers. All 13 cases occurred among 76 workers who had handled evergreen seedlings and moss (attack rate = 17%). For those exposed to evergreens and moss, the risk of infection increased as worktime exposure to moss increased (attack rates: less than 10 hours, 8%; 10-19 hours, 12%; greater than 19 hours, 33%). While environmental samples of moss from the Wisconsin supplier were negative, Sporothrix schenckii was cultured from multiple samples of the sphagnum moss obtained from one of six Pennsylvania tree nurseries, representing the nursery that was identified as the source for 79 (94%) of the moss-associated cases. Differences in tree-handling procedures at this nursery--including the use of 1- to 3-year-old moss to pack seedlings, use of a pond water source to wet the moss, use of an organic polymer gel on the seedling root system, and underground storage and longer storage of moss-packed seedlings before shipping--suggested possible explanations for the association. Efforts to prevent sporotrichosis among persons handling evergreen seedlings should include the use of alternate types of packing material (e.g., cedar wood chips or shredded paper) and protective clothing such as gloves and long-sleeved shirts.

Adolescent↗
PubMed1992

Nosocomial pneumonia: epidemiology and infection control.

Elderly, debilitated, or critically ill patients are at high risk for hospital acquired or nosocomial respiratory tract infection. Gram-negative bacilli, Staphyloccoccus aureus, and anaerobes colonizing the oropharynx are the most frequent etiologic agents. Colonization of the oropharynx may be related to the patient's age, underlying disease, nutritional status, prior exposure to antibiotics, supine position, and gastric colonization. Nosocomial pathogens may also be acquired from the hands of hospital personnel, contaminated equipment or fluids. The absence of sensitive and specific methods for accurate diagnosis remain a concern. Despite treatment with appropriate antimicrobial therapy, there is a high mortality and morbidity. Measures for the prevention of nosocomial pneumonia should include compliance with infection control principles, appropriate use of antibiotics, proper patient position, and removal of potential sources of cross colonization.

Aerosols↗
PubMed1992

Use of a mouse model to evaluate clinical and environmental isolates of Sporothrix spp. from the largest U.S. epidemic of sporotrichosis.

Five clinical and 69 environmental isolates from the largest U.S. epidemic of sporotrichosis were evaluated in NYLAR male mice following intravenous injection of 5 x 10(6) to 2 x 10(8) conidia per mouse. The clinical isolates and eight environmental isolates produced 100% mortality in groups of three mice each between 12 and 24 days after injection. These virulent isolates grew at 37 degrees C, were dematiaceous by virtue of melanin (melanized) on permissive media (e.g., potato dextrose agar), produced ovoid conidia borne sympodially on lateral conidiophores and pleurogenously about the main hyphal axis, and were identified as Sporothrix schenckii. Two melanized environmental isolates that grew at 35 degrees C but not at 37 degrees C were not virulent and had subtle morphological differences from S. schenckii. The remaining environmental isolates were not melanized, were not virulent, and were not S. schenckii; five were identified as Ophiostoma stenoceras and the remainder were identified as Sporothrix spp. Quantitative organ cultures revealed that clinical isolates grew exponentially in livers and testes, in contrast to an isolate of O. stenoceras that was eliminated from liver, lung, and spleen but that persisted in the testes throughout the 14-day sample period. This model helped to confirm the identification of S. schenckii isolates obtained from the environment.

Animals↗
PubMed1991

Isolation and characterization of Sporothrix schenckii from clinical and environmental sources associated with the largest U.S. epidemic of sporotrichosis.

The largest recorded epidemic of sporotrichosis in the United States occurred in 1988 and involved a total of 84 cases in 15 states. All cases were associated with Wisconsin-grown sphagnum moss. Twenty-one clinical isolates of Sporothrix schenckii and 69 environmental isolates of Sporothrix spp. from the epidemic were characterized and compared. The environmental isolates were recovered from 102 samples of sphagnum moss and other material by using direct plating techniques. Characteristics examined included macroscopic and microscopic morphology, conversion to a yeast phase, exoantigen reactions, and virulence in mice. On the basis of these studies, eight environmental isolates were identified as S. schenckii, five were identified as Ophiostoma stenoceras, and the remainder were identified as Sporothrix species. The environmental isolates of S. schenckii were recovered from moss samples from one Pennsylvania nursery and from three New York State Soil and Water Conservation districts, but none were recovered from moss directly from the bogs in Wisconsin.

Disease Outbreaks↗
PubMed1991

Prostaglandin F2 alpha stimulates inositol 1,4,5-trisphosphate and inositol 1,3,4,5-tetrakisphosphate formation in bovine luteal cells.

The present studies were conducted to further evaluate inositol phosphate formation and metabolism in prostaglandin F2 alpha (PGF2 alpha)-stimulated bovine luteal cells. Corpora lutea were dispersed with collagenase, and luteal cells were prelabeled for 3 h with [3H]inositol. Inositol phosphates produced in response to PGF2 alpha were analyzed by ion exchange column chromatography and HPLC. Time-course experiments revealed that significant increases in inositol trisphosphate (InsP3) were apparent within 5 sec of incubation with PGF2 alpha. Increases in inositol bisphosphate (InsP2) were also apparent within 5 sec. InsP1 and InsP4 were observed after a short (5-sec) lag period. HPLC revealed that PGF2 alpha provoked rapid (5 sec) increases in inositol 1,4,5-trisphosphate (Ins 1,4,5-P3), which was rapidly converted to inositol 1,3,4,5-tetrakisphosphate (Ins 1,3,4,5-P4) and inositol 1,3,4-trisphosphate (Ins 1,3,4-P3). The primary inositol bisphosphate isomer present in PGF2 alpha-stimulated bovine luteal cells was inositol 1,4-bisphosphate (Ins 1,4-P2), with lesser amounts of Ins 1,3-P2. Inositol monophosphates were also increased. These findings were confirmed in studies in which the metabolism of purified [3H]Ins 1,4,5-P3 was followed temporally in saponin-permeabilized bovine luteal cells. Additional studies demonstrated the presence of an enzyme, InsP3-3-kinase, in the cytosolic fraction of bovine corpora lutea. InsP3-3-kinase phosphorylated Ins 1,4,5-P3 to form Ins 1,3,4,5-P4. The activity of InsP3-3-kinase was calcium dependent and was enhanced by calmodulin at low calcium concentrations. Calmidazolium, a calmodulin inhibitor, reduced InsP3-3-kinase activity in a concentration-dependent manner. These results demonstrate the presence of multiple polyphosphorylated inositol phosphates in PGF2 alpha-stimulated bovine luteal cells. The isomers were formed via the action of a specific calcium/calmodulin-regulated kinase (InsP3-3-kinase), which phosphorylated Ins 1,4,5-P3 during agonist-mediated hydrolysis of phosphatidylinositol 4,5-bisphosphate. These data suggest that the inositol tris/tetrakisphosphate pathway is an important sequelae to PGF2 alpha-stimulated inositol phospholipid hydrolysis, and that the pathway may be activated during agonist-mediated calcium mobilization.

Animals↗
PubMed1990

Microbiology and potential virulence of Sporothrix cyanescens, a fungus rarely isolated from blood and skin.

Sporothrix cyanescens has been recovered from blood and a finger lesion at several medical centers in the United States. The morphology and physiology of these and three additional isolates were studied. S. cyanescens was distinguished from S. schenckii and S. fungorum by white to lavender colonial pigmentation and from S. schenckii also by the formation of secondary conidia. All isolates of S. cyanescens grew well at 37 degrees C, were cycloheximide susceptible, strongly urease positive, and benomyl resistant, failed to hydrolyze starch, and were inhibited by sodium chloride in vitro at a concentration of greater than or equal to 12%. Study of S. cyanescens in a murine model by using intravenous inoculation failed to demonstrate an invasive pathogenic potential. The validity of the transfer of S. cyanescens to the new genus Cerinosterus Moore is discussed.

Cell Division↗
PubMed1981

Automated immunofluorescence test for toxoplasmosis.

A soluble-antigen fluorescent-antibody technique for serodiagnosis of toxoplasmosis, employing a special fluorometer (FIAX; International Diagnostic Technology, Santa Clara, Calif.), was evaluated in comparison with a standard indirect fluorescent-antibody method which uses a fluorescence microscope. Titers obtained by the new method on 324 serum samples correlated very well with those of the conventional procedure. There was good intralaboratory and interlaboratory agreement in runs on selected samples. The FIAX method is simple, rapid, and reliable and has the advantage of objectivity.

Antibodies↗