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P Small

Publications and source records attributed to P Small.

At least 19 recordsLinked to original sources

Th-2 type cytokine receptors in allergic rhinitis and in response to topical steroids.

OBJECTIVES: Th-2 type cytokine production (Interleukin-4 [IL-4] and interleukin-5 [IL5]) has been demonstrated to play a significant role in the pathophysiology of allergic rhinitis (AR), and the treatment of AR with topical corticosteroids has been shown to reduce the expression of Th-2 type cytokines in vivo. However, the contribution and expression of Th-2 type cytokine receptors in AR and their response to corticosteroid treatment remain to be clarified. Objectives of the current study are 1. To examine the expression of the cytokine IL-4 and IL-5 receptors (IL-4R and IL-5R) in a nasal allergen challenge model and to contrast this with the expression of the receptor for the Th-1 type cytokine, interferon-gamma receptor (IFN-gammaR), and 2. to examine the effects of pretreatment with topical corticosteroid before allergen challenge on the expression of these same receptors. STUDY DESIGN: Randomized prospective study involving 14 ragweed-allergic subjects evenly divided between placebo and corticosteroid pretreatment. METHODS: Immunocytochemistry (alkaline phosphatase-antialkaline phosphatase labeling [APAAP] technique) was used to stain nasal biopsy specimens before and after allergen challenge. Antibodies used included anti-CD3, CD4, CD8, major basic protein (MBP), IL-4R, IL-5R, and IFN-gammaR. RESULTS: Following allergen challenge, we observed a significant increase in the Th-2 type cytokine receptors (IL-4R and IL-5R; P<.05), as well as a significant decrease in the expression of the Th-1 type cytokine receptor (IFN-gammaR; P<.05). Pretreatment with topical corticosteroids before nasal allergen challenge resulted in decreased expression of IL-4R (P<.05) and IL-5R (P<.05) and increased expression of IFN-gammaR (P<.05). Further, IL-4R and IL-5R expression correlated with eosinophil infiltration in the tissues. CONCLUSIONS: We have demonstrated that in AR, cytokine receptors for IL-4, IL-5, and IFN-gamma follow a similar pattern to their ligands. In addition, pretreatment with topical corticosteroids was shown to alter the cytokine receptor expression pattern from a Th-2 profile more toward a Th-1 profile.

Administration, Topical↗

Emerging and reemerging infectious diseases: a multidisciplinary perspective.

Predictions that infectious diseases would be eliminated as a major threat to human health have been shattered by emerging and reemerging infections, among them acquired immunodeficiency syndrome (AIDS), hemorrhagic fevers, marked increases in infections caused by antimicrobial-resistant bacteria, and the resurgence of tuberculosis and malaria. Understanding the dynamics of emerging and reemerging infections is critical to efforts to reduce the morbidity and mortality of such infections, to establish policy related to preparedness for infectious threats, and for decisions on where to use limited resources in the fight against infections. In order to offer a multidisciplinary perspective, 23 infectious disease specialists, epidemiologists, geneticists, microbiologists, and population biologists participated in an open forum at Emory University on emerging and reemerging infectious diseases. As summarized below, the group addressed questions about the definition, the identification, the factors responsible for, and multidisciplinary approaches to emerging and reemerging infections.

Acquired Immunodeficiency Syndrome↗

Th-2 type cytokine receptors in allergic rhinitis and in response to topical steroids.

OBJECTIVES: Th-2 type cytokine production (interleukin-4 [IL-4] and interleukin-5 [IL-5]) has been demonstrated to play a significant role in the pathophysiology of allergic rhinitis (AR), and the treatment of AR with topical corticosteroids has been shown to reduce the expression of Th-2 type cytokines in vivo. However, the contribution and expression of Th-2 type cytokine receptors in AR and their response to corticosteroid treatment remain to be clarified. Objectives of the current study are 1. To examine the expression of the cytokine IL-4 and IL-5 receptors (IL-4R and IL-5R) in a nasal allergen challenge model and to contrast this with the expression of the receptor for the Th-1 type cytokine, interferon-gamma receptor (IFN-gammaR), and 2. to examine the effects of pretreatment with topical corticosteroid before allergen challenge on the expression of these same receptors. STUDY DESIGN: Randomized prospective study involving 14 ragweed-allergic subjects evenly divided between placebo and corticosteroid pretreatment. METHODS: Immunocytochemistry (alkaline phosphatase-antialkaline phosphatase labeling [APAAP] technique) was used to stain nasal biopsy specimens before and after allergen challenge. Antibodies used included anti-CD3, CD4, CD8, MBP, IL-4R, IL-5R, and IFN-gammaR. RESULTS: Following allergen challenge, we observed a significant increase in the Th-2 type cytokine receptors (IL-4R and IL-5R; P < .05), as well as a significant decrease in the expression of the Th-1 type cytokine receptor (IFN-gammaR; P < .05). Pretreatment with topical corticosteroids before nasal allergen challenge resulted in decreased expression of IL-4R (P < .05) and IL-5R (P < .05) and increased expression of IFN-gammaR (P <.05). Further, IL-4R and IL-5R expression correlated with eosinophil infiltration in the tissues. CONCLUSIONS: We have demonstrated that in AR, cytokine receptors for IL-4, IL-5, and IFN-gamma follow a similar pattern to their ligands. In addition, pretreatment with topical corticosteroids was shown to alter the cytokine receptor expression pattern from a Th-2 profile more toward a Th-1 profile.

Administration, Topical↗

Expression of IgE heavy chain transcripts in the sinus mucosa of atopic and nonatopic patients with chronic sinusitis.

We have recently shown the increased mRNA expression of interleukin (IL)-4 and IL-13 in sinus biopsies from allergic subjects with chronic sinusitis (ACS), whereas only IL-13 mRNA was elevated in biopsies obtained from nonallergic subjects with chronic sinusitis (NCS). In the lymph nodes and spleen, these cytokines may promote IgE production through transcriptional activation of the germline IgE heavy chain promoter, an event which precedes immunoglobulin isotype switching to IgE in B cells. We hypothesized that local expression of IL-4 and/or IL-13 might act by inducing germline IgE heavy chain transcript expression locally in the sinus mucosa of chronic sinusitis patients. Mucosal sinus biopsies were obtained from 13 patients with ACS, 12 subjects with NCS, and 11 normal control individuals. The numbers of B cells in the sinus mucosa were studied by immunocytochemistry with anti-CD20 monoclonal antibodies. In situ hybridization was performed using antisense radiolabeled riboprobes complementary to the IgE epsilon -heavy chain germline (Iepsilon) and heavy chain constant region (Cepsilon) gene transcripts. Riboprobes specific for the IgG gamma-heavy chain constant region (Cgamma) were used as an isotype control. Immunocytochemical analysis indicated augmented numbers of CD20-positive B cells in the biopsies obtained from ACS patients compared with NCS subjects (P < 0.05) and normal control subjects (P < 0.01). Statistically significant increases were observed in the numbers of cells expressing Iepsilon and Cepsilon transcripts in the sinus mucosa of ACS patients compared with those with NCS (P < 0. 001) and normal controls (P < 0.001), while Cgamma RNA expression did not differ significantly between the groups. In three randomly selected ACS biopsies, 92-100% of cells expressing Cepsilon transcripts and 100% of Iepsilon RNA-positive cells coexpressed CD20 immunoreactivity. Cells expressing Cepsilon transcripts were also significantly increased in NCS compared with normal controls (P < 0. 05). The results of this study suggest that local IgE class switching occurs in the pathogenesis of ACS and that ACS and NCS are both associated with increased expression of Cepsilon transcripts.

Adult↗

Interleukin-4, interleukin-5, and granulocyte-macrophage colony-stimulating factor receptor expression in chronic sinusitis and response to topical steroids.

Chronic sinusitis and its associated eosinophilic infiltrate are believed to be mediated, at least in part, by the upregulation of Th-2 cytokines, including interleukin-4, interleukin-5, and granulocyte-macrophage colony-stimulating factor (GM-CSF). Interleukin-4 is involved in IgE production and in eosinophil recruitment through upregulation of vascular cell adhesion molecule-1. Interleukin-5 and GM-CSF are involved in eosinophil growth and survival. The aim of this study was to investigate the expression of receptors for these cytokines in the sinus mucosa of subjects with chronic sinusitis. Using the technique of in situ hybridization to detect specific cytokine receptor messenger RNA, we studied the sinus mucosa of subjects with nonallergic chronic sinusitis, subjects with allergic chronic sinusitis, subjects with allergic chronic sinusitis treated with topical steroids, and normal controls. Our data demonstrate higher expression of interleukin-4 receptor in subjects with allergic chronic sinusitis than in controls (p < 0.001) and higher expression of interleukin-5 receptor in both subjects with nonallergic chronic sinusitis and subjects with allergic chronic sinusitis than in controls (p < 0.001, p < 0.001). The expression of interleukin-4 receptor and interleukin-5 receptor was higher in subjects with allergic chronic sinusitis than in subjects with nonallergic chronic sinusitis (p < 0.001). GM-CSF receptor expression was also found to be higher in subjects with allergic chronic sinusitis and subjects with nonallergic chronic sinusitis than in controls (p < 0.001, p < 0.001). In contrast to interleukin-4 receptor and interleukin-5 receptor, however, expression of GM-CSF receptor was higher in subjects with nonallergic chronic sinusitis than in subjects with allergic chronic sinusitis (p < 0.001). In subjects with allergic chronic sinusitis treated with topical corticosteroids, the expression of interleukin-4 receptor and interleukin-5 receptor messenger RNA levels was significantly lower than levels in patients with allergic chronic sinusitis who were not taking topical steroids (p < 0.001, p < 0.001). Steroid treatment had no effect on GM-CSF receptor messenger RNA expression. In conclusion, our data support a role for Th-2 cytokine receptors in the pathophysiology of chronic sinusitis. Further, our data lend support to the theory that differential activation of distinct cytokine pathways mediates inflammation in chronic sinusitis depending on whether there is associated allergy. Finally, treatment with topical corticosteroids has been demonstrated in chronic sinusitis to downregulate receptors for interleukin-4 and interleukin-5.

Administration, Topical↗

A comparison of triamcinolone acetonide nasal aerosol spray and fluticasone propionate aqueous solution spray in the treatment of spring allergic rhinitis.

BACKGROUND: Many nasal corticosteroids with different potencies and formulations are available, but they have all been proven safe and effective. The clinical relevance, if any, of these differences is not yet completely established. OBJECTIVE: We sought to compare the efficacy, safety, and patients' acceptance of triamcinolone acetonide aerosol spray and fluticasone propionate aqueous solution in the treatment of spring allergic rhinitis. METHODS: After a drug-free baseline evaluation, patients with rhinitis were randomized to receive either a triamcinolone aerosol spray of 110 microg in each nostril once daily (n = 117) or a fluticasone solution spray of 100 microg in each nostril once daily (n = 116) in a single-blind, parallel-group study. The Rhinitis Index Score (sum of scores of symptoms on a scale from 0 to 3) was evaluated daily, in the morning before drug administration, for 21 days. The efficacy of each treatment was assessed by the mean reduction from baseline in the Rhinitis Index Score and in individual symptom scores. Patients' acceptance of the study drugs was also monitored by a daily questionnaire. RESULTS: Reductions of the Rhinitis Index Score (mean +/- SEM) were 4.20 +/- 0.21 and 4.60 +/- 0.21 for triamcinolone and fluticasone, respectively (p = 0.23). There were no statistically significant differences between the drugs in the reduction of any of the individual symptoms. Patients expressed statistically significant differences between the drugs regarding acceptance; different properties of the aerosol and the solution were appreciated differently. CONCLUSIONS: This study shows that triamcinolone acetonide aerosol and fluticasone propionate solution sprays are both clinically equally effective, safe, and well tolerated for the treatment of spring pollen allergic rhinitis.

Administration, Inhalation↗

IL-4 and IL-13 expression in chronic sinusitis: relationship with cellular infiltrate and effect of topical corticosteroid treatment.

OBJECTIVE: Chronic sinusitis with allergy (ACS) and without allergy (NCS) are inflammatory diseases with considerable morbidity. The present study was undertaken to investigate, by in situ hybridization, the expression of IL-13 and IL-4 mRNA in sinus biopsy sections. METHOD: Specimens were obtained from subjects with NCS (n = 12), ACS (n = 13), ACS on steroid therapy (n = 11), and normal controls (n = 11). The composition of the inflammatory infiltrate was also examined in all cases. RESULTS: The number of cells expressing IL-4 and IL-13 transcripts was significantly higher in subjects with ACS compared to normal controls. In contrast, the numbers of IL-13 but not IL-4 mRNA-positive cells were increased in the NCS subjects compared to the normal controls. IL-4 and IL-13 mRNA expression was suppressed in ACS subjects on topical steroid therapy compared to untreated patients. There was no significant difference in the numbers of eosinophils between the ACS subjects treated with steroids and those who were not treated, but the steroid-treated patients demonstrated significantly higher numbers of CD8+ cells in the sinus mucosa. Increased numbers of CD8+ cells were also observed in subjects with NCS compared with ACS subjects and normal controls. CONCLUSIONS: These results demonstrate that increased IL-13 expression is an important feature of allergic and nonallergic patients with chronic sinusitis. Furthermore, our data indicate that IL-13 and IL-4 are under differential regulation in NCS subjects.

Adolescent↗

Upregulation of Th-2 cytokine receptors in atopy- and nonatopy-associated chronic sinusitis.

OBJECTIVE: This study was conducted to investigate the expression of alpha IL5 and alpha GM-CSF receptors (alpha IL5r and alpha GM-CSFr) mRNA in the paranasal sinus mucosa of atopic and nonatopic subjects with chronic sinusitis compared to controls. DESIGN: This was a prospective study of patients presenting with the diagnosis of chronic sinusitis of at least 6 months' duration. METHOD: Fourteen patients with stable chronic sinusitis (7 atopic, 7 nonatopic) and 7 controls were included, from whom sinus mucosal biopsies were obtained and examined for membrane-bound alpha IL5r and alpha GM-CSFr mRNA using in situ hybridization. RESULTS: There was a significant difference in the number of cells expressing alpha IL5r mRNA per high-power field in both atopic and nonatopic subjects compared to controls, and in the number of cells expressing alpha GM-CSFr mRNA in both atopic and nonatopic subjects compared with controls. The number of alpha IL5r mRNA-positive cells was significantly greater in the atopic versus nonatopic groups, whereas alpha GM-CSFr mRNA-positive cells were greater in number in the nonatopic versus atopic groups. CONCLUSION: Both alpha IL5r and alpha GM-CSFr are upregulated in chronic sinusitis, suggesting that increases in both Th-2 cytokines and their receptors may be important in the pathology of the disease. Furthermore, the predominant associations of alpha IL5r with atopic chronic sinusitis and alpha GM-CSFr with nonatopic chronic sinusitis suggest that the chronic inflammation in this condition may arise from differential activation of distinct cytokine pathways depending on whether or not there is associated atopy.

Biopsy↗

Evaluation of dust and dust mite nasal provocation.

BACKGROUND: The relevance of positive epicutaneous tests to dust mite in patients with perennial rhinitis is often not apparent clinically. OBJECTIVE: We attempted to assess and compare intranasal challenges with both dust and dust mite allergens in skin test positive patients with perennial symptoms. METHODS: Thirteen patients allergic to both dust and dust mite by prick testing were challenged intranasally with each allergen at 2-week intervals. Nasal provocation was performed stepwise to a maximum dose of 2,000 pnu (dust) and 500 pnu (mite). The control group was composed of seven symptomatic patients with negative skin tests. RESULTS: Control patients were uniformly clinically unresponsive to maximum dose. Allergic patients varied considerably in sensitivity but all reacted clinically to at least the final dose with an early response. There were no obvious late phase reactions. Both dust and mite provoked an early phase increase of eosinophil cationic protein in the nasal secretions of control patients. For allergic patients there were early increases of eosinophil cationic protein, prostaglandin D2 and leukotriene C4. Late phase elevations were not observed. CONCLUSION: Dust and mite skin test-positive patients with perennial rhinitis had similar early phase responses to intranasal challenge both clinically and with elevations of inflammatory mediators. Clinically unresponsive control patients did show elevated eosinophil cationic protein levels suggesting a possible nonspecific, non-IgE mediated affect of both dust and mite allergens on the nasal mucosa.

Adult↗

Acid and base resistance in Escherichia coli and Shigella flexneri: role of rpoS and growth pH.

Escherichia coli K-12 strains and Shigella flexneri grown to stationary phase can survive several hours at pH 2 to 3, which is considerably lower than the acid limit for growth (about pH 4.5). A 1.3-kb fragment cloned from S. flexneri conferred acid resistance on acid-sensitive E. coli HB101; sequence data identified the fragment as a homolog of rpoS, the growth phase-dependent sigma factor sigma 38. The clone also conferred acid resistance on S. flexneri rpoS::Tn10 but not on Salmonella typhimurium. E. coli and S. flexneri strains containing wild-type rpoS maintained greater internal pH in the face of a low external pH than strains lacking functional rpoS, but the ability to survive at low pH did not require maintenance of a high transmembrane pH difference. Aerobic stationary-phase cultures of E. coli MC4100 and S. flexneri 3136, grown initially at an external pH range of 5 to 8, were 100% acid resistant (surviving 2 h at pH 2.5). Aerobic log-phase cultures grown at pH 5.0 were acid resistant; survival decreased 10- to 100-fold as the pH of growth was increased to pH 8.0. Extended growth in log phase also decreased acid resistance substantially. Strains containing rpoS::Tn10 showed partial acid resistance when grown at pH 5 to stationary phase; log-phase cultures showed < 0.01% acid resistance. When grown anaerobically at low pH, however, the rpoS::Tn10 strains were acid resistant. E. coli MC4100 also showed resistance at alkaline pH outside the growth range (base resistance). Significant base resistance was observed up to pH 10.2. Base resistance was diminished by rpoS::Tn10 and by the presence of Na+. Base resistance was increased by an order of magnitude for stationary-phase cultures grown in moderate base (pH 8) compared with those grown in moderate acid (pH 5). Anaerobic growth partly restored base resistance in cultures grown at pH 5 but not in those grown at pH 8. Thus, both acid resistance and base resistance show dependence on growth pH and are regulated by rpoS under certain conditions. For acid resistance, and in part for base resistance, the rpoS requirement can be overcome by anaerobic growth in moderate acid.

Acids↗

Nonspecific nasal reactivity and smoking.

Twenty-three smoking and twenty-four nonsmoking patients both with and without symptomatic rhinitis and/or atopy were challenged intranasally with histamine. Histamine sensitivity was measured by changes in flow rates assessed by anterior rhinomanometry. The median threshold for both smokers and nonsmokers was 0.4 mg histamine. Small numbers limited the analyses of the subgroups. The data did not suggest that cigarette smoke increases nonspecific nasal reactivity as measured by histamine challenge.

Administration, Intranasal↗

Multicenter trial of fluticasone propionate aqueous nasal spray in ragweed allergic rhinitis.

A 4-week multicenter, double-blind, placebo-controlled, parallel-group trial was carried out with 416 adults with ragweed allergic rhinitis to compare 200 micrograms of fluticasone propionate once daily and 100 micrograms of fluticasone propionate twice daily with placebo. Compared with placebo, both groups receiving fluticasone propionate had greater number of symptom free days (P < .01), lower median symptom scores (P < .01), and greater number of days not requiring rescue medications (P < .001). No significant differences for individual symptoms were found between the two fluticasone propionate groups except that those taking the twice daily dosage used less antihistamine (P < .01) and had greater number of days free of rescue medications (P < .05). Adverse events were comparable between the three groups. These results indicate that topical intranasal fluticasone propionate 200 micrograms once daily and 100 micrograms twice daily are both efficacious and well tolerated.

Administration, Intranasal↗

Effects of intensity of early response to allergen on the late phase of both the nose and skin.

Thirty-seven asymptomatic ragweed-sensitive patients and ten controls were challenged both epicutaneously and intranasally with ragweed. Clinical assessments of both early (20 minutes) and late (six hours) phase reactions of skin (mm) and nose (clinical score) were performed. A positive routine nasal challenge was defined as a clinical score 5 (0-12). Augmented nasal challenges were 10-fold higher than routine for each patient. Nasal lavage was performed at baseline, after positive challenge, one, two, and six hours postchallenge. Mediators assayed included histamine, eosinophil cationic protein (ECP), leukotrine C4 (LTC4), and prostaglandin D2 (PGD2). All 37 patients had an early skin reaction. Only 28/37 had a late response correlating with the early. Twenty-one patients had routine nasal challenges; 14 then volunteered for an augmented challenge. The remaining 16 had augmented challenges only. All had a nasal clinical early response, but late responses were infrequent (9). The early phase PGD2 was higher in augmented compared with routine challenges (P < .05) as were the late histamine (P < .05) and ECP (P < .05). The early skin test correlated with early LTC4 (P < .001) and PGD2 (P < .05). The early and late LTC4 (P < .05) and PGD2 (P < .01) were also related. In summary, late phase reactions of both the nose and skin are related to the intensity of the early response.

Adolescent↗

Suppression of epicutaneous reactivity by terfenadine and loratadine.

We compared the relative antihistaminic effects of loratadine (10 mg), terfenadine (120 mg), and placebo in patients with tree pollen-induced allergic rhinitis. Wheals were produced by epicutaneous tests with serial dilutions of histamine phosphate, tree and grass pollen extracts before ingestion of medication. Repeat tests were performed after seven days of treatment. Terfenadine was more effective than both loratadine (P less than .01) and placebo (P less than .001) at suppressing histamine induced wheals. Terfenadine was more effective than placebo (P less than .01), but not loratadine at inhibiting both tree-induced and grass-induced epicutaneous reactions. In this study, terfenadine was more potent than loratadine in inhibiting both histamine-induced and allergen-induced epicutaneous wheals.

Cyproheptadine↗

Sustained improvement in asthma with long-term use of formoterol fumarate.

Inhaled formoterol fumarate, a long acting beta 2 agonist, produces bronchodilatation that is sustained for approximately 12 hours. To determine whether such bronchodilator effects are maintained and asthma control sustained during chronic administration, we monitored airflow indices and clinical control in 112 asthmatic patients who self administered formoterol twice daily for periods ranging from 9 to 12 months. Subjects were recruited immediately following completion of a 3-month double-blind comparison of formoterol, 12 micrograms, bid versus salbutamol, 200 micrograms, qid. Assessments were conducted at baseline, 3, 6, and 9 months, where baseline represents the final visit of the 3-month comparative study. Patients were asked to complete diary cards and twice daily PEFR for a 2-week period before each assessment. Throughout the follow-up study, there was no indication of worsening of asthma control or deteriorating lung function. For the patients who continued to receive formoterol, the previous improvement in asthma control and lung function was maintained at the level reached in the 3-month study. There was an improvement in flow rates and asthma symptoms in the group switched from salbutamol to formoterol by the first clinic visit. This improvement in asthma control and lung function was maintained over the subsequent 6 months. Formoterol was well tolerated during the study period. We conclude that prolonged use of formoterol fumarate twice daily results in sustained improvement in symptoms and flow rates in asthma with no evidence of tachyphylaxis.

Adolescent↗

Relationship between allergen-specific skin testing and nasal provocation in patients with perennial rhinitis.

Patients with perennial rhinitis were evaluated by allergen challenge epicutaneously and intranasally. Nasal provocation was assessed by clinical score, graded 0-12, to include rhinomanometry, secretions (mL), sneezes, and stuffy nose. All 40 patients with perennial symptoms had no clinical history of seasonal exacerbations but did have both positive skin tests and nasal provocation to the same allergen. Skin test wheel size correlation with nasal provocation (P less than .02).

Allergens↗

Does nasal provocation play a role in the diagnosis and management of ragweed-induced allergic rhinitis?

Twenty-seven patients with ragweed allergic rhinitis were evaluated before the season by allergen-induced nasal reactivity. Symptom scores were recorded during the season, and repeat nasal challenges performed at the end. Nasal response to ragweed insufflation did not predict seasonal symptoms. No change in threshold reactivity occurred at the end of the season, once peak symptoms had passed. In the evaluation of patients with allergic rhinitis, specific nasal challenge did not help predict seasonal clinical symptoms.

Double-Blind Method↗

Wegener's granulomatosis presenting as temporal arteritis.

A granulomatous giant cell vasculitis of the temporal artery was observed in a biopsy specimen from a patient with corresponding clinical symptoms. Within weeks, the new onset of pulmonary infiltrates and renal failure prompted biopsy of the patient's kidney. A necrotizing glomerulonephritis, compatible with a diagnosis of Wegener's granulomatosis, was present. Vasculitis of the temporal artery may be a feature of Wegener's granulomatosis.

Aged↗