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R Rhoades

Publications and source records attributed to R Rhoades.

8 recordsLinked to original sources
PubMed2001

Stinging ants.

Ants belong to the order Hymenoptera, along with bees, wasps, yellow jackets, etc., they are the most successful animal genera in this world. It is their selfless social structure which accounts for their huge impact. Their effect on man ranges from the parasol ant, which makes plant cultivation untenable in certain parts of South America, to Solenopsis Invicta in the southeastern United States of America, which kill ground dwelling birds and small animals, harass livestock, and renders farmland unusable. With the exception of the Bulldog Ant of Australia (which is the size of a medium cockroach) direct toxic effects are not a lethal threat to man. Human fatalities and morbidity are related to secondary infections of excoriated stings or allergic anaphylaxis. This article reviews history and recent developments regarding stinging ants around the world.

Adult↗
PubMed1997

Comparison of the efficacy, safety and acceptability of cefixime and amoxicillin/clavulanate in acute otitis media.

BACKGROUND: Use of a beta-lactamase stable antibiotic is called for in cases of acute otitis media (AOM) likely to be caused by beta-lactamase-producing Haemophilus influenzae or Moraxella catarrhalis. Two beta-lactamase-stable agents commonly used for empirical treatment of AOM are amoxicillin/clavulanate and cefixime. METHODS: A multicenter, randomized clinical trial compared cefixime (CFX; 8 mg/kg once daily) with amoxicillin/clavulanate (A/C; 40 mg/kg/day in three divided doses) for the treatment of children with AOM. Three hundred thirteen children were randomly assigned to a 10-day course of either CFX (n = 158) or A/C (n = 155). Based on history, physical examinations and otoscopic and tympanometric assessments, clinical responses were evaluated as cure, improvement, failure, relapse or nonevaluable. Compliance and patient/parent acceptability were also analyzed. RESULTS: Overall favorable clinical responses (cure plus improvement) were comparable post-therapy for the two treatments (CFX = 76%; A/C = 77%). Significant differences in response rates for both treatments were noted among different geographic regions, with the highest response rates observed in the Northeast and South. Acceptability of CFX was significantly better than that of A/C (P = 0.0001), and the adverse experience rate was lower (P = 0.001). The most frequently reported adverse experiences were diarrhea (CFX 15.2%, A/C 29.7%) and vomiting (CFX 3.2%, A/C 10.32%). Relapse rates were 26% for CFX and 29% for A/C. CONCLUSION: This study demonstrated that CFX has comparable clinical efficacy and a better adverse events profile than A/C when used to treat AOM of childhood.

Acute Disease↗
PubMed1996

Axon and ganglion cell injury in rabbits after percutaneous trigeminal balloon compression.

New Zealand white rabbits were used to determine whether the changes in the Vth cranial nerve sensory root after compression were associated with the loss of a specific subclass of Vth cranial nerve ganglion cells, the disappearance of a distinct subset of primary afferent terminals in Vth cranial nerve nucleus caudalis, and/or injury to a specific axonal fiber type. There was no significant difference in the size of surviving ganglion cells after Vth cranial nerve compression, as measured 2 to 3 months after injury (P > 0.5, n = 4). Densitometric analysis of the nerves of rabbits that survived > 2 months after compression showed no significant difference in the immunoreactivity of substance P and calcitonin gene-reactive protein between compressed and control sides (P > 0.1, n = 4). Fink-Heimer staining of the Vth cranial nerve subnucleus caudalis revealed that transganglionic degeneration was most dense in the deeper layers, which are the sites of termination of large myelinated fibers. Ultrastructural evaluation of the type of myelinated axons injured by Vth cranial nerve compression in rabbits killed 7, 14, 37, and 270 days after injury was studied, and morphometric analysis was performed. The frequency distribution of axon diameters was significantly different for injured and control areas. The injured areas had higher ratios of small (< 3-microns diameter) to large-diameter axons compared to control distribution. These data indicate that balloon compression results in loss of fibers from the Vth cranial nerve sensory root and extensive transganglionic degeneration in the Vth cranial nerve brain stem complex. Cell size measurements and immunocytochemical data suggest that there is no specific loss of small ganglion cells or fine-caliber primary afferents. These experiments suggest that balloon compression relieves trigeminal pain by injuring the myelinated axons involved in the sensory trigger to the pain.

Afferent Pathways↗
PubMed1991

Racial aspects of ambulatory blood pressure.

Ambulatory blood pressure measurements, recorded by a Del Mar Pressurometer IV, were performed in 71 patients (25 blacks and 46 whites) with documented essential hypertension (supine diastolic blood pressure 95-119 mmHg) after four weeks of placebo treatment. Each 24-hour ambulatory BP measurement was calibrated with manual measurements within 5 mmHg and was repeated according to the daily conditions (work status) of the original recording. Ambulatory BP measurements were recorded every 15 minutes over 24 hours on two separate occasions one week apart. The mean of two 24-hour measurements was the value for the individual patient. Analyses of variance indicated no significant difference in the mean age, height, weight, 24-hour ambulatory systolic or diastolic BP, 8 am to 12 noon systolic or diastolic ambulatory BP, or 12 midnight to 4 am ambulatory systolic or diastolic BP for blacks versus whites. Among the subset of females, the 20 blacks were older than the 23 whites. Despite this age difference, there was no significant difference in height, weight or 24-hour, 8 am to 12 noon, or 12 midnight to 4 am ambulatory BP measurements. Therefore, this study does not support a racial difference in the level of ambulatory blood pressure measurement in these hypertensive patients.

Ambulatory Care↗