Biomedical subjects
R B Turner
Publications and source records attributed to R B Turner.
Epidemiology, pathogenesis, and treatment of the common cold.
OBJECTIVE: Reading this article will reinforce the reader's knowledge of the pathogenesis of the common cold. The rationale for current and potential therapies for the common cold are reviewed in the context of current concepts of the pathogenesis of these illnesses. DATA SOURCES AND STUDY SELECTION: A MEDLINE literature search was done using the search terms common cold, rhinovirus, and viral respiratory infection. The search was restricted to the English language. Articles were selected for review if the title and/or abstract suggested the content was relevant to the subject of this review. The bibliographies of selected articles were used as a source of additional literature. RESULTS: Recent studies suggest that the host response to the virus is an important contributor to the pathogenesis of the common cold. Inflammatory mediators, especially the pro-inflammatory cytokines, appear to be an important component of this response and present an attractive target for new interventions for common cold therapies. Currently available treatments for the common cold have limited efficacy against specific symptoms. These therapies should be selected to treat the specific symptoms that are perceived to be the most bothersome by the patient.
Effectiveness of clemastine fumarate for treatment of rhinorrhea and sneezing associated with the common cold.
Limited data support the use of first-generation antihistamines for treatment of the common cold. The purpose of this study was to test the effectiveness of clemastine fumarate, a first-generation antihistamine, for treatment of sneezing and rhinorrhea associated with naturally occurring common colds. Four hundred three subjects (202 clemastine fumarate recipients and 201 placebo recipients) who reported new onset (< 24 hours) of cold symptoms that included rhinorrhea or sneezing were studied. At baseline (day 1), the mean symptom-severity scores +/- SEM for the clemastine fumarate and placebo groups were not significantly different. The mean rhinorrhea-severity score +/- SEM was not different on day 2; however, on day 3, the mean rhinorrhea-severity score +/- SEM was 1.02 +/- 0.07 for the clemastine fumarate group and 1.39 +/- 0.07 for the placebo group (P < .001). This treatment effect persisted on day 4. A significant effect on sneezing was noted on days 2-4. Sedation occurred in 14% of the clemastine fumarate-treated subjects and 1.5% of the placebo-treated subjects (P < .0001).
Randomized controlled trial of clemastine fumarate for treatment of experimental rhinovirus colds.
We used a rhinovirus challenge model to test the therapeutic efficacy of clemastine fumarate for reducing sneezing and nasal secretion in a double-blind, randomized clinical trial. Clemastine fumarate (1.34 mg) or placebo was administered at 8 A.M. and 8 P.M. for 4 days, beginning 24 hours, 36 hours, 48 hours, and 60 hours after viral challenge. Infected evaluable subjects who received clemastine (n = 75) had reduced sneeze-severity scores compared with those who received placebo (n = 75) on illness days 2 (0.3 vs. 0.5; P = .003), 3 (0.4 vs. 0.8; P = .0003), 4 (0.3 vs. 0.5; P = .025), and 5 (0.1 vs. 0.3; P = .03); sneeze counts for infected evaluable subjects (vs. counts for those who received placebo) were reduced on illness days 2 (1.5 vs. 3.1; P = .01), 3 (1.7 vs. 5.6; P = .0001), and 5 (0.7 vs. 1.9; P = .03). Infected evaluable subjects who received treatment had reduced rhinorrhea scores (compared with those who received placebo) on illness days 2 (0.7 vs. 1.0; P = .04) and 3 (0.6 vs. 0.9; P = .04) and had reduced nasal secretion weights on day 3 (3.6 g vs. 6.3 g; P = .03). Over 4 days of treatment, mean sneeze scores for infected evaluable subjects (vs. scores for those who received placebo) were reduced by 50%, mean sneeze counts by 57%, mean rhinorrhea scores by 27%, and mean nasal secretion weights by 35%. Other cold symptoms were unaffected by treatment. Treatment with clemastine was associated with an excess incidence of dry mouth (6%), dry nose (19%), and dry throat (17%).
Effect of topical adrenergic decongestants on middle ear pressure in infants with common colds.
BACKGROUND: Otitis media is frequently a complication of the common cold. Obstruction of the eustachian tube ostia by nasopharyngeal edema has been suggested as a cause of this complication. OBJECTIVE: To determine the effect of a topical adrenergic decongestant on middle ear pressure in infants with common cold symptoms. METHODS: The study was conducted with a randomized, double blinded, placebo-controlled design. Middle ear pressure was determined in infants 6 to 18 months old who had common cold symptoms. Infants with abnormal middle ear pressure (< or = -100 mm H2O) in either ear were treated with intranasal phenylephrine drops or placebo. The effect of the treatment on middle ear pressure in ears with abnormal pressure at baseline was determined 1 h later. RESULTS: Twenty-three of 44 infants with abnormal middle ear pressures received intranasal phenylephrine drops and 21 received placebo. Middle ear pressure remained abnormal after treatment with phenylephrine in 29 of 33 (88%) ears and after treatment with placebo in 26 of 34 (76%). The mean change in middle ear pressure after treatment was +23 mm H2O in the active group and +40 mm H2O in the placebo group. CONCLUSIONS: Treatment of nasal obstruction with topical adrenergic decongestants does not improve abnormal middle ear pressures during the common cold.
Red Book recommendations on ribavirin challenged.
Explore the source record for details and available documents.
Historical cohort evaluation of ribavirin efficacy in respiratory syncytial virus infection.
Evaluation of ribavirin therapy for respiratory syncytial virus infection of the lower respiratory tract is problematic because of multiple risk factors and variable severity of illness in respiratory syncytial virus-infected patients. To address these difficulties we used multivariate analysis and performed a historical concurrent cohort study in two children's hospitals one of which had used ribavirin since licensing and one that had not utilized ribavirin therapy. The medical records of 158 patients who satisfied the American Academy of Pediatrics inclusion criteria for receiving ribavirin were analyzed for three seasons (1988 to 1991). No significant benefit of ribavirin therapy could be appreciated for the whole group in length of stay (median, 5.0 vs. 6.5 days), days on oxygen therapy (median, 5 vs. 3), progression to ventilator status (3.8 vs. 3.9%) or mortality (1.9% vs. 1.9%) for ribavirin treatment vs. supportive care. Multivariate analysis failed to uncover a beneficial effect of ribavirin when all risk factors were considered. No significant differences were noted when ventilated and nonventilated patients were examined separately. Our data raise questions about the efficacy of ribavirin when used in common practice and suggest that further prospective study, with appropriate analysis, is needed to justify the continued widespread use of this drug.
Passive immunization for prevention of rotavirus illness in healthy infants.
Infant formula supplemented with bovine antibody (BCIg) to human rotavirus has been reported to prevent or modify rotavirus infection and illness. The purpose of this field trial was to determine the safety and feasibility of passive immunization with bovine antibody for the prevention of rotavirus infection and illness in healthy infants. Sixty-four infants, 31 of whom received BCIg and 33 placebo, participated in the study. Rotavirus infection was detected in 11 (35%) and 14 (42%) infants in the 2 groups, respectively. Symptomatic rotavirus infection was documented in 1 (3%) of the infants receiving BCIg and in 6 (18%) of the infants who received the placebo (P > 0.05). The number of days with diarrhea/1000 days of observation was significantly less in the BCIg group, 4.2, than in the placebo group, 16.8 (P < 0.01). Similarly the number of days with rotavirus-associated diarrhea/1000 days was less in the BCIg group, 1.0, than in the placebo group, 13 (P < 0.01). This study establishes the feasibility of providing passive immunity for the prevention of rotavirus illness in healthy infants.
Efficacy of oral WIN 54954 for prophylaxis of experimental rhinovirus infection.
The efficacy of oral WIN 54954 for the prevention of rhinovirus infection and illness was tested in two randomized, double-blinded, placebo-controlled volunteer challenge studies. Volunteers were inoculated with rhinovirus type 39 (MIC of WIN 54954, 0.17 microgram/ml) or rhinovirus type 23 (MIC, 0.016 microgram/ml). The volunteers received two doses of drug (600 mg per dose) or placebo on the first day; this was followed by three doses on each of the subsequent 5 days. All volunteers were challenged with virus after the third dose of study drug. No significant antiviral or clinical effect was detected in either study. Pharmacokinetic studies revealed that on the last day of drug administration, 38 of 39 (97%) volunteers had trough levels of WIN 54954 in plasma greater than the MIC for the respective virus. Nasal wash specimens collected on the same day revealed a detectable level in only 6 of 24 (25%) volunteers at the peak (range, 6 to 24 ng/ml) and in only 2 of 14 (14%) volunteers at the trough (range, 6 and 7 ng/ml). These results suggest that the lack of efficacy of WIN 54954 against rhinovirus may be related to an inability to deliver sufficient drug to the site of viral infection.
Updated recommendations for safety-testing of viral inocula used in volunteer experiments on rhinovirus colds.
Explore the source record for details and available documents.
Prospective comparison of the immune response of infants to three Haemophilus influenzae type b vaccines.
The antibody response to three Haemophilus influenzae type b vaccines was examined in 134 infants 17 to 22 months of age. Sera were collected from each subject before and 1 month after vaccination with either purified H. influenzae type b capsular polysaccharide (polyribosyl-ribitol phosphate (PRP] or one of two protein-conjugated vaccines (PRP-D or HbOC). Comparison of the two conjugate vaccines revealed that HbOC produced an antibody response greater than or equal to 1.0 micrograms/ml in 96% compared with 72% who were vaccinated with PRP-D (P less than 0.05). The isotype distribution of the antibodies produced by the two vaccines was similar. While all of the vaccines resulted in higher concentrations of anticapsular IgG1 than IgG2, the IgG1:IgG2 ratio was significantly higher in subjects immunized with HbOC. The IgG1:IgG2 ratio was similar in subjects immunized with PRP or PRP-D. The clinical significance of these observations remains to be determined.
Clinical manifestations of exacerbations of cystic fibrosis associated with nonbacterial infections.
The purpose of this study was to determine whether acute pulmonary exacerbations of cystic fibrosis associated with nonbacterial infections are clinically distinguishable from other exacerbations. Eighty exacerbations in 54 patients were studied. Exacerbations associated with influenza (n = 8) were compared with those associated with other nonbacterial infections (n = 15) and those in which no nonbacterial infection was detected (n = 57). Patients with influenza had lower Shwachman scores and were more likely to be seropositive for C-reactive protein than patients in the other two groups. Patients with influenza had a mean decrease in forced expiratory volume per second of 26%, compared with test results obtained before the exacerbation. In contrast, the mean decrease in forced expiratory volume per second was 6% for other nonbacterial infections and 12% for the group without nonbacterial infection (p less than 0.05 for both comparisons). The forced expiratory flow in first 25% of vital capacity decreased 44% in the influenza group compared with 13% and 17% in the other two groups, respectively (p less than 0.01 for both comparisons). The influenza group also had a higher proportion of patients with at least a 20% decrease in forced expiratory volume per second and forced expiratory flow in first 25% of vital capacity than the other two groups had (p less than 0.05 for all comparisons). These data suggest that influenza is associated with severe exacerbations in patients with cystic fibrosis and support recommendations for efforts to prevent influenza in this population.
The role of neutrophils in the pathogenesis of rhinovirus infections.
Explore the source record for details and available documents.
The high rate of blood donor exposure for critically ill neonates.
The purpose of this study was to determine the number and volume of red blood cell (RBC) transfusions and the number of donors a newborn is exposed to during his or her newborn intensive care unit (NICU) stay. On one day at the Medical University of South Carolina (MUSC) and two days at the University of Virginia Hospital (UVH) all babies who had or were receiving RBCs comprised the study group. Patient records were reviewed at discharge. Fifty-two (70%) of the 75 NICU babies had or were receiving RBCs and were enrolled. The average number of RBC transfusions was nine (range 1 to 28, median 7) and the average transfusion volume was 16.5 ml (range 5 to 60) for a total volume of 148 ml transfused during a NICU stay. Each baby was exposed to an average of 6.9 donors (range 1 to 25, median 6.5). The practice of splitting RBC packs to share among different infants and of giving multiple small volume transfusions maximizes donor exposure and transfusion-related infectious risks in this population.
Safety and tolerance of ocular administration of recombinant alpha interferon.
The safety, tolerance, and levels of drug in the nasal cavity produced by an ocular formulation of interferon were determined at four dosages in a placebo-controlled, double-masked trial. Interferon given by the ocular route was generally well tolerated, although a dose-related occurrence of subjective symptoms was detected.
Accuracy of radiographic differentiation of bacterial from nonbacterial pneumonia.
The chest roentgenogram is an accepted tool for the diagnosis of pneumonia. Little information is available, however, addressing the ability of physicians to distinguish bacterial from nonbacterial pneumonias by examination of the chest roentgenogram. Five different observers evaluated 36 chest films from patients with pneumonia who had a laboratory proven etiologic diagnosis. The sensitivity of roentgenogram diagnosis of bacterial pneumonia ranged from 42-58 percent. When clinical and laboratory data were provided to the observers the sensitivity ranged from 42-92 percent. This study indicates that chest film examination is too insensitive to be useful for the selection of patients who have bacterial pneumonia from those whose pneumonia is non-bacterial.
Rhinovirus infection of human embryonic lung fibroblasts induces the production of a chemoattractant for polymorphonuclear leukocytes.
Polymorphonuclear leukocytes (PMNLs) appear in the nasal mucosa during rhinovirus colds before the onset of symptoms. This study describes a chemoattractant for PMNLs that is elaborated by human embryonic lung fibroblast cells infected with rhinovirus. Chemotaxis assays were done in a 48-well microchemotaxis chamber with normal adult PMNLs. Medium supernatants from rhinovirus-infected cell culture attracted 87 +/- 6 (mean +/- SE) PMNLs/10 high-power fields (x450) compared with 38 +/- 6 PMNLs/10 high-power fields attracted by medium from uninfected cell cultures (P less than .0001). Elaboration of the chemoattractant was not a result of cell destruction and did not require the presence of infectious virus. This chemoattractant produced by human fibroblast cells may contribute to the influx of PMNLs into the nasal mucosa during rhinovirus infection. The PMNLs may, in turn, have a role in producing symptoms of the common cold.
Safety and efficacy of topical norfloxacin versus tobramycin in the treatment of external ocular infections.
Bacterial conjunctivitis appears to resolve more rapidly when treated with appropriate topical antimicrobial agents. In this multicenter, randomized, double-blind study of efficacy and safety, patients with presumed bacterial external eye infections were assigned to topical therapy with 0.3% norfloxacin or 0.3% tobramycin. A total of 120 patients were enrolled. Of the total, 65 had documented bacterial infections and were evaluable; 59 of these patients had bacterial conjunctivitis. All of the patients with documented infections were cured or improved regardless of the drug treatment regimen or in vitro susceptibility testing results. The most common bacteria isolated were Haemophilus influenzae, Streptococcus pneumoniae, alpha-hemolytic streptococci, Staphylococcus aureus, and Staphylococcus sp. No patients had serious adverse reactions attributed to their therapy. Norfloxacin ophthalmic solution seems to be a safe, effective, and appropriate agent for the treatment of bacterial external eye infections.