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Biomedical subjects

R W Fox

Publications and source records attributed to R W Fox.

At least 19 recordsLinked to original sources
PubMed2004

Absolute-frequency measurements with a stabilized near-infrared optical frequency comb from a Cr:forsterite laser.

A frequency comb is generated with a chromium-doped forsterite femtosecond laser, spectrally broadened in a dispersion-shifted highly nonlinear fiber, and stabilized. The resultant evenly spaced comb of frequencies ranges from 1.1 to beyond 1.8 microm. The frequency comb was referenced simultaneously to the National Institute of Standards and Technology's optical frequency standard based on neutral calcium and to a hydrogen maser that is calibrated by a cesium atomic fountain clock. With this comb we measured two frequency references in the telecommunications band: one half of the frequency of the d/f crossover transition in 87Rb at 780 nm, and the methane v2 + 2v3 R(8) line at 1315 nm.

Journal Article↗
PubMed2000

Allergy to iguana.

BACKGROUND: Furry animals produce allergens that can cause allergic rhinitis and asthma. In contrast, scaly animals, such as lizards, are assumed not to be allergenic. OBJECTIVE: We sought to evaluate a 32-year-old man who complained of allergic rhinitis and asthma symptoms that occurred exclusively in his own home. He had dogs and cats at home but denied any increase in symptoms specifically associated with these pets. Skin prick testing initially performed to 42 common aeroallergens, including cat, dog, and house dust mite, elicited negative results. He later reported that the symptoms were worse on exposure to his pet iguanas. METHODS: Skin prick tests were subsequently performed to an extract made from scales from his pet iguana. Extracts were also prepared from several zoo reptiles. Immunoassays for IgE antibody, as well as IgE immunoblots, were performed by using these extracts and the patient's serum. RESULTS: The skin prick test result with the pet iguana scale extract was positive. The patient's serum contained IgE antibody to his own pet iguana and to a zoo iguana. CONCLUSION: Our patient's history, skin test results, and in vitro studies clearly demonstrate that he is allergic to iguana. Physicians should be aware that such allergy to scaly pets may occur and should not restrict history taking to questions about furry pets.

Adult↗
PubMed1994

Air cleaners: a review.

Air cleaners are manufactured by many companies in the United States. Air cleaning devices vary widely in design, methods of operation, cost, and level of efficiency. No universally accepted performance standards are available to compare the capabilities of the available air cleaners. These units are classified as household appliances, not as medical devices. Clinical studies have failed to substantiate a significant impact of air cleaners on patients' symptoms. Air cleaners should be used when it is desirable to further reduce airborne contaminant concentrations that are not eliminated by other environmental control measures. Air cleaners should not be the primary means of improving indoor air quality.

Adsorption↗
PubMed1993

Allergenicity of the cat flea (Ctenocephalides felis felis)

Adult fleas, spent and unspent culture media were extracted and the radio-allergosorbent test (RAST) performed with sera of 48 cat flea skin test-positive individuals from the Tampa Bay area of Florida. Sixteen sera (33.6%) had a positive RAST to the cat flea extract prepared in our laboratory [1.7-11.4% of the total counts (TC) added]. Six of the 16 sera (12.5%) also contained specific IgE to allergens in the spent medium (0.8-3.3% TC). The allergen composition and strength were studied by RAST inhibition of two commercial cat flea extracts and compared with our in-house flea extract. The results demonstrated similar allergen compositions and different potencies. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of the in-house flea extract showed several Coomassie blue-stained bands (10-85 kD). SDS-PAGE immunoblots revealed five IgE-binding bands at 34, 35, 39, 54 and 60 kD. Flea allergens were quantified in eight house dust samples using RAST inhibition assays and expressed as RAST inhibition units; five of these samples contained detectable levels. Cat flea allergens may contribute to the allergenicity of house dust in areas of heavy flea infestation.

Allergens↗
PubMed1992

Environmental control of indoor air pollution.

Indoor air pollution is becoming an increasing problem in industrialized countries. Most people spend their time indoors which results in chronic exposure to indoor allergens and irritants. New products have been introduced to the environment to which humans are not immunologically adapted. This article describes the main sources of indoor air pollution and the best ways to control exposure to indoor air pollutants.

Air Pollution, Indoor↗
PubMed1992

Relative efficacy and safety of loratadine, hydroxyzine, and placebo in chronic idiopathic urticaria.

The efficacy and safety of a new non-sedating antihistamine, loratadine (Clarityn, CAS 79794-75-5) 10 mg q.d., was compared to the classical antihistamine, hydroxyzine 25 mg t.i.d. and placebo in a 4-week (optional 12 week) randomized, double-blind, multi-center study in 203 patients with chronic idiopathic urticaria. Efficacy evaluations included weekly physician and patient assessments of pruritus, overall disease condition, and therapeutic response to treatment. Loratadine and hydroxyzine were significantly more effective than placebo and clinically comparable to each other as measured by all efficacy evaluations at each visit. Loratadine was safe and well tolerated with sedation and dry mouth similar to placebo and significantly less than hydroxyzine.

Adolescent↗
PubMed1988

A multicenter, open study of the non-sedating antihistamine, terfenadine (Seldane), in the maintenance therapy of seasonal allergic rhinitis.

A multicenter open study was conducted throughout the 1984 fall pollen season to assess the possible development of tolerance or loss of efficacy to terfenadine in the maintenance therapy of patients with seasonal pollinosis. Patients with proven allergic pollinosis were entered into a 1-week initial treatment period taking terfenadine 60 mg bid and only those who responded to the initial treatment with "moderate" to "complete" relief continued on terfenadine throughout a 4 to 11-week pollen season for evaluation of continued efficacy. A total of 179 patients from five study centers were enrolled in the initial treatment period and 154 (86%) responded to terfenadine with "moderate" to "complete" relief of symptoms. Of these 154 patients who continued terfenadine treatment, approximately 90% of the patients maintained the same degree of relief throughout the pollen season. All symptoms of seasonal pollinosis including nasal congestion improved significantly the first day of treatment. This improvement in symptoms continued during the first week and remained unabated throughout the pollen season. The incidence of adverse events was low with sedation being reported by only 2.8% of patients at some time point during the study. It is concluded that terfenadine is a safe and effective non-sedating antihistamine in the maintenance therapy of seasonal allergic pollinosis and that tolerance is not noted during continued administration.

Adult↗
PubMed1988

Double-blind comparison of terfenadine, chlorpheniramine, and placebo in the treatment of chronic idiopathic urticaria.

The efficacy of terfenadine, a nonsedating H1 antihistamine, in the management of chronic idiopathic urticaria was compared with chlorpheniramine and placebo in a parallel multicenter trial. Subjects with symptoms of hives for 3 days per week for at least 6 weeks were initially screened and admitted if no identifiable cause for symptoms could be determined. Patients entered a single-blind placebo period, and if hives of moderate severity were present for at least 3 days during the week, they were randomly assigned in a double-blind fashion to take terfenadine, 60 mg twice daily, chlorpheniramine, 4 mg three times a day, or placebo for 6 weeks. Data were analyzed for 122 patients. Those patients receiving both active treatments noted significant improvement in symptoms: pruritus, redness, number of hives, and waking hours during which hives were present, at the end of the first day of therapy. Symptom control by terfenadine was statistically superior to placebo during all 6 weeks, as rated by both patients and investigators. However, statistical significance was not achieved for chlorpheniramine at all observation points. Diphenhydramine was permitted as a relief medication for refractory symptoms and was taken by 52% of subjects receiving placebo, 26% taking chlorpheniramine, and only 9% of patients who were receiving terfenadine. In addition to providing superior symptom control, terfenadine caused less drowsiness and fatigue than chlorpheniramine. Terfenadine is a useful therapeutic agent for primary management of chronic idiopathic urticaria.

Adolescent↗
PubMed1987

Amino acid sequence at the citrate allosteric site of rabbit muscle phosphofructokinase.

Previously, this laboratory has demonstrated [Colombo, G., & Kemp, R. G. (1976) Biochemistry 15, 1774-1780] that under appropriate conditions the citrate inhibitory binding site of rabbit skeletal muscle phosphofructokinase can be covalently modified by using pyridoxal phosphate and sodium borohydride. In the current study, phosphofructokinase was modified by [3H]pyridoxal phosphate and sodium borohydride with or without the addition of citrate to protect the ligand binding site. The modified proteins were digested with trypsin, and the peptides were separated by high-pressure liquid chromatography. A comparison of the tryptic chromatographic profiles showed that while the label was broadly distributed among nine peaks in the elution profile of the enzyme modified in the presence of the protective ligand, a single peptide contained 70% of the total radioactivity of the enzyme modified in the absence of citrate. This peptide was presumed to contain at least part of the citrate inhibitory site of the enzyme. The sequence of the peptide was determined and shown to match with positions 528-536 of phosphofructokinase with the modified residue being Lys-529. A comparison of the sequence with that of procaryotic phosphofructokinase indicated that a homologous residue in the enzyme from Bacillus stearothermophilis is critical to an allosteric site. A second peptide that was the most abundant labeled peptide in the digest of the enzyme modified in the presence of citrate was found to be identical with the second most abundant peptide of the digest from the unprotected enzyme. This peptide corresponded to residues 681-692 with the lysine at position 684 being the site of phosphopyridoxylation.(ABSTRACT TRUNCATED AT 250 WORDS)

Allosteric Site↗
PubMed1987

Melkersson-Rosenthal syndrome.

Two patients were referred to the University of South Florida College of Medicine Allergy and Immunology Clinic for evaluation of "angioedema." Patient 1 presented with intermittent severe lip edema, and patient 2 presented with lip and facial swelling together with facial palsy. Multiple symptomatic treatments had been ineffective. Both patients were ultimately found to have Melkersson-Rosenthal syndrome, a rare granulomatous disorder of undetermined cause that must be considered in a differential diagnosis of facial edema. The patients are presented in detail to call attention to the diagnosis of the condition in order that unnecessary treatment, with attendant side effects, may be avoided.

Adult↗
PubMed1986

The treatment of mild to severe chronic idiopathic urticaria with astemizole: double-blind and open trials.

Astemizole is a new H1 histamine-receptor antagonist that has a long elimination half-life and high H1-receptor affinity. This double-blind study evaluated the safety and efficacy of astemizole in the treatment of chronic idiopathic urticaria (more than or equal to 3 months). Seventeen male and 34 female adult patients with chronic idiopathic urticaria entered the 2-month study. After a 48- to 72-hour washout, half the subjects were prerandomized to receive astemizole (10 mg), and the other half received placebo. Placebo-treated patients who were unable to complete the full 8 weeks because of uncontrolled chronic urticaria symptoms were entered into a 2-month open astemizole trial. Treatment with astemizole, as measured at the end point of each patient's treatment and compared to placebo, resulted in significant improvement of pruritus, erythema, number of wheals, frequency of urticarial attacks, and control of urticaria (p less than or equal to 0.03). The overall response to astemizole was significantly better than for placebo, according to both the investigator's and the patient's global evaluations (p less than 0.01) and as indicated by dropouts caused by treatment failure with placebo (p = 0.005). Six of 26 (24%) of the placebo-treated patients in the double-blind study had good to excellent results on the basis of global assessments. Thirteen of 16 patients with placebo-treatment failures who received astemizole in the open trial improved significantly from baseline symptoms of pruritus, erythema, and number of wheals (p less than or equal to 0.05). No significant side effects were reported except mild sedation in three astemizole-treated subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1983

A longitudinal study of a patient with acquired immunodeficiency syndrome using T cell subset analysis.

Acquired Immunodeficiency Syndrome (AIDS) has recently been documented in patients in association with opportunistic infections, Kaposi's sarcoma, cytomegalovirus infections, and recreational drug use. AIDS is characterized by cutaneous energy, diminished peripheral lymphocyte responses to mitogens and antigens, and abnormal T cell subpopulations. These patients have been described as having decreased total T (T3+) cell numbers, virtual elimination of the T helper (T4+) cell population, and an increased percentage of the T suppressor-cytotoxic (T8+) cell population. T cell subset monitoring has not been performed during the course of this disorder. A four month longitudinal study of the T cell subsets of a 30 year old bisexual male with AIDS revealed changes in his T cell subpopulations and in his ability to respond in a one way mixed lymphocyte culture (MLC). The results indicated that the patient's previously abnormal T cell subpopulations returned to near normal values during a period of spontaneous clinical improvement. The patient's MLC response also returned to normal in association with the return of the T helper cell population. The patient's T cell subpopulation and MLC response subsequently became abnormal and remained abnormal until the patient died. Thus, it appears that T cell subpopulations may spontaneously improve during the course of this disorder. T cell subset analysis may offer a means of monitoring the clinical course of this disorder as well as the response to therapeutic agents.

Acquired Immunodeficiency Syndrome↗
PubMed1983

Theophylline kinetics in a geriatric group.

The influence of age, sex, and smoking on theophylline disposition was studied in 38 healthy subjects ranging in age from 26 to 81 yr. There were 8 young (less than 60 yr) and 30 geriatric (greater than 60 yr) subjects, including 28 men (8 smokers) and 10 women (3 smokers). A crossover experimental design was used. A single dose of theophylline elixir (5 mg/kg lean body weight [LBW]) was given as a reference product to all subjects. One week later a sustained-release (SR) theophylline tablet (8 and 6 mg/kg LBW) was given to the young and the geriatric subjects. Serum theophylline concentrations were determined by HPLC. Theophylline elimination (t1/2 beta) is shorter in the geriatric group (6.93 and 8.14 hr); total body theophylline clearance is greater in the geriatric group (44.39 and 32.97 ml/kg/hr), and the apparent volume of distribution is also greater in the geriatric group (26.29 and 22.97 l). Sex and smoking did not influence any of the parameters studied. In 93% of the geriatric subjects, serum theophylline levels of 8 to 20 micrograms/ml were reached at steady state with the SR tablet. Theophylline dose reduction based on an arbitrary age limit is not, therefore, invariably indicated.

Adult↗
PubMed1983

Study of oxtriphylline SA in 50 asthmatics.

Fifty clinically stable patients with asthma on maintenance theophylline therapy, mean dose of 15 mg kg-1 per day, were switched to an equivalent dose (X 1.56) of oxtriphylline SA for seven doses. All subjects remained clinically stable after the change during the study period. Oxtriphylline SA appears to be useful for the maintenance treatment of asthma and can be safely substituted for other theophylline maintenance regimens.

Adult↗
PubMed1982

Neurologic sequelae following the imported fire ant sting.

Four cases are described in which neurologic disturbances are the presenting symptoms after the imported fire ant (IFA) sting. The neurologic sequelae include focal motor and grand mal seizures and a mononeuropathy. The possible pathogenesis of these disorders is discussed.

Adult↗