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Notes: As part of a new, compact heavy ion injector for the AGS/RHIC complex at Brookhaven National Laboratory we are developing an electron beam ion source (EBIS) that would satisfy present and future requirements. Such a source should be capable of producing intensities of, e.g., Au35+ ions of about 3×109 particles/pulse or U45+ of about 2×109 particles/pulse. To achieve this, the required e-beam intensity is 10 A, at a pulse length of 100 ms. An EBIS test stand has been constructed, designed for the full electron beam power and having close to 1/2 of the trap length of an EBIS for RHIC. Initial electron beam tests have resulted in a 50 μs, 13 A electron beam. Ion production and extraction has been shown with a 3.1 A, 50 ms electron beam, achieving an ion yield of 19 nC/pulse (neutralization degree of 61%); fast extraction trials have yielded extracted ion pulses of 1 mA peak current and 18 μs at FWHM. Details of the test stand construction, results of the electron beam studies, and properties of the extracted ion pulse are presented. © 2000 American Institute of Physics.

Notes: Fifty dust samples were collected from the mattresses and bedroom floors of 25 subjects with allergic asthma in Cartagena, Colombia, in order to identify house dust mites and quantitate Der p I, Derf I and Blomia tropicalis allergens. The geometric mean of the total mite density per gram of dust was 418 (range, 40–2280). Twenty-two samples (44%) had more than 500 mites and four, less than 100. B. tropicalis and Dermatopha-goides pteronyssinus were found in 96% and 90% of the samples, accounting for 40.1% and 35.7% of the total mites, respectively. Cheyletus malaccensis, Chortoglyphus arcuatus, Pyroglyphus africanus, Orihatids, Grallacheles bakeri. Tarsonemus spp., Suidasia spp., Dermatophagoides farinae and unidentified mites accounted for the rest. The geometric mean of the total mites/gram of dust in mattresses (563.9) was significantly higher than in floor dust (309. 1), P 〈 0.01. Allergen concentrations and mite numbers were analysed by Spearman rank correlations: B. tropicalis mites vs B. tropicalis allergen, r= 0.54, P〈0.001; D. pteronyssinus mites vs Der p I, r= 0.52, P〈 0.001. A negative correlation was obtained between B. tropicalis mites and Der p I. Allergens derived from B. tropicalis and other domestic mite species may play an important role in sensitization and allergic symptoms in Cartagena, Colombia.

Notes: The prevalence of specific IgE to the storage mites Aleuroglyphus ovatus (Ao) and Chortoglyphus arcuatus (Ca) was studied in 77 individuals with allergic asthma and/or chronic allergic rhinitis. All these individuals had a positive skin test (weal ≥ 3 mm) to extracts of Dermatophagoides pteronyssimis (Dp) and/or Dermatophagoides farinac (Df). Sera from 29 non-atopic individuals were used as controls. A RAST was considered positive when a serum bound ≥1% of the total counts added. The prevalence of a positive RAST to Dp was 75.3%, and to at least one of the two storage mites (Ao and Ca), 76.6%. Among patients with a positive RAST to Dp. 79.3% and 75.8% were RAST positive to Ao and Ca, respectively. RAST inhibition studies with a pool of sera from 13 subjects with high RAST binding to all three mites showed significant crossreactivity between Ao and Ca and minimal to moderate crossreactivity between Dp and Ao and Co, This study demonstrates that Sensitization to Ao and Ca is common in individuals with respiratory allergies in Cartagena, Colombia and suggests that Ao, Ca and Dp have unique and common allergenic determinants.

Notes: Background Sensitization to soybean hull (SH) allergens occurs in subjects from Argentina, a soybean producer country. However, the causative allergens have not been identified. The purposes of this study are to: (i) identify the SH allergens using sera of 29 subjects with asthma and/or allergic rhinitis from Argentina exposed to soybean dust who have a positive (weal with SH/weal with histamine ≥ 0.5) skin prick test to SH; and (ii) determine the N-terminal amino acid sequence of a major 50 K SH allergen that sensitizes this population.Methods All sera were assayed for specific IgE (RIA), IgG4 (ELISA), and IgE and IgG4-Western blots. A sera pool from 10 healthy subjects was a negative control. N-terminal amino acid sequencing was performed by the Edman degradation method.Results Positive specific IgE only was found in 12/29 (41.4%), IgG4 in 3/29 (10.3%), and both IgE and IgG4 in 14/29 (48.3%) sera. IgE-Western blot demonstrates: (i) an allergen, MW 50 K (51.7% binding); (ii) one or two distinct allergens, MW 〈 20.2 K (72.4% binding), depending on the sera; and (iii) 1–5 additional IgE binding proteins, MW 〉 20.2 to 〈 46.9 K (41.4% binding), depending on the sera. IgG4-Western blot demonstrates: (i) a band, MW 70K (31% binding); (ii) a band, MW 50 K (17.2% binding); (iii) one or two additional bands, MW 〈 20.2 K (51.7% binding), depending on the sera; and (iv) a band, MW 〉 20.2 to 〈 28.5 K (20.7% binding). The 50 K allergen N-terminal amino acid sequence of the first 17 amino acids indicates a significant homology with chlorophyll A-B binding protein precursors from tomato, spinach, and petunia.Conclusions Specific IgE and IgG4 to SH are common in sera from allergic individuals living in rural areas in Argentina. SH contain an IgE binding protein, MW about 50 K, not previously described. Sensitization to this allergen is common in subjects who are repeatedly exposed to soybean dust inhalation.

Notes: Background The prevalence of sensitization to Euroglyphus maynei (E. maynei) in the United States has not been reported previously.Objectives To determine: (l) the prevalence of skin-test reactivity in allergic subjects to E. maynei compared to D. pteronyssinus, D. farinae, and B. tropicalis and (2) the allergenic crossreactivity between D. pteronyssinus and E. maynei.Methods Skin testing with extracts of B. tropicalis and E. maynei (1:50 w/v) and standardized D. pteronyssinus and D. farinae extracts (1:50 w/v; 10000 AU/mL) provided data on 250 subjects (87 males and 163 females) aged 9–77 years (mean age, 39.8 years) with possible allergic respiratory diseases. RAST inhibition assays were used to study crossreactivity between D. pteronyssinus and E. maynei.Results One hundred (40%) of 250 subjects had insignificant or no allergic diseases. Of the 150 allergic subjects (53 males, 97 females), 101 (67.3%) had a positive test (a percutaneous test with a weal diameter ≥ 3 mm larger than the saline control) to at least one mite species; 60.7%, 60.0%, 28.7%, and 52.0% reacted to D. farinae, D. pteronyssinus, B. tropicalis, and E. maynei, respectively; 40(26.7%) reacted to the four mite species. Positive tests to D. farinae, D. pteronyssinus, B. tropicalis, or E. maynei alone occurred in six (4.0%), four (2.7%), two (1.3%), and 0%, respectively. D. pteronyssinus and E. maynei showed moderately high crossreactivity in RAST inhibition assays.Conclusion There is a high rate of skin-test reactivity to E. maynei in Florida. Moderately high crossreactivity exists between E. maynei and D. pteronyssinus.

Notes: Background A low MW allergen from soybean hull, Gly m 1, with two isoallergens, Gly m 1 A and Gly m 1 B, was associated with the asthma outbreaks that occurred in Cartagena, Spain. Using sera of asthmatic epidemic patients (AEP) from Barcelona, three main soybean hull allergens, two of them with MWs atid pIs identical to those reported for Gly m 1 A and Gly m 1 B, were identified.Objective The purpose of this study was to purify and to study the N-terminal amino acid sequence of the third allergen, which has a MW of 8 kDa.Method The purification procedure combined the double dialysis method and preparative isoelectofocusing (IEF). Specific IgE determination to the fractions obtained demonstrated three peaks, one of them corresponding to the 8 kDa allergen. The pooled fractions containing this allergen were studied by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE), SDS-PAGEAVestern blot and IEF/Westem blot. Only a band with a MW of 8 kDa and a pI of 6 was obtained. Its allergenic activity was measured and it was demonstrated that the allergenicity of soybean hull correlates with the presence of the 8 kDa allergen. The N-terminal amino acid sequence of the first 20 amino acids, which was registered at the PIR Data Submission as the N-terminal partial sequence of Gly m 2, was determined according the Edman degradation method.Results Gly m 2 N-terminal amino acid sequence lacks homology with that reported for the allergen Gly m 1 but has a homology of 71% with a storage protein from cotyledon of Vigna radiata (cow pea) and 64% with a‘disease response protein’ from Pisum sativum (green pea). These results suggest that Gly m 2 in soybeans could protect against diseases which affect soybean plants.Conclusion This study demonstrates the existence of another soybean hull allergen, Gly m 2, partially responsible for the soybean asthma outbreaks that occurred in Barcelona, Spain.

Notes: Adult fleas, spent and unspent culture media were extracted and the radio-atlergosor-bent 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 thespent 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 immunoblols 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 llea infestation.

Notes: Background: The effectiveness of acaricides in homes is controversial.Objective: To determine whether disodium octaborate tetrahydrate (DOT) combined with vacuuming lowers dust mite numbers and their allergens in carpets and sofas.Methods: A 6-month study was carried out with 93 homes, which were randomized into three groups: (i) active, received DOT; (ii) placebo, received water; and (iii) control, received no application. Active and placebo homes were vacuumed weekly. Dust was collected from carpets and sofas at the start of the study and every 2 months thereafter and quantified for live, total mites, and mite allergen levels.Results: At 2 months, live mite numbers in active carpets were 3 ± 1, in placebo carpets 129 ± 48, and in control carpets 177 ± 39 mites/g. The corresponding numbers in sofas were 3 ± 2, 81 ± 31, and 134 ± 45 mites/g, respectively (P 〈 0.001 active vs placebo and vs. control). Live mites in carpets and sofas remained lower in the active group at 6 months (P 〈 0.001). Total mites in active carpets decreased from 555 ± 69 at baseline to 223 ± 32 mites/g at 6 months (P 〈 0.001) and mite allergen levels from 1.36 ± 0.13 to 0.85 ± 0.16 μg/g (P 〈 0.001). Total mites in active sofas remained unchanged, but mite allergen levels decreased from 1.48 ± 0.25 at baseline to 0.7 ± 0.15 μg/g at month 6 (P 〈 0.05).Conclusion: DOT kills mites in carpets and sofas, and, combined with vacuuming, effectively reduces total mites in carpets and mite allergen levels in carpets and sofas.

Notes: Background:  Soybean hulls (SHs) cause respiratory allergies. This study investigates the allergenicity of soybean varieties (SVs) by in vivo and in vitro tests.Methods:  Ten SVs were studied: (a) five with a proved clinical relevance (SVs 1, 2, 3, 4, 5), the last four with a ‘dull’ phenotype; (b) five of undetermined relevance, three of them (SVs 6, 7, 8) with a ‘shiny’ phenotype, and two (SVs 9 and 10) with a ‘dull’ phenotype. Extracts from all 10 SVs were used to skin prick test (SPT) 21 subjects sensitized to SHs. Positive and negative sera pools prepared from sera of subjects sensitized or not to SHs, respectively, were utilized to perform in vitro experiments (specific IgE and IgG4 determinations, SDS-PAGE/IgE-Western blot, and IgE-inhibition).Results:  In this study, it was found that 52.4, 52.4, 57.1, 71.4, 80.9, 42.9, 57.1, 71.4, 52.4, and 38.1% subjects had a positive SPT with SVs 1–10, respectively (P NS). Specific IgE values to SVs 1–10 obtained with the positive pool are 28.3, 26.4, 29.9, 28.3, 26.8, 4.8, 13.4, 6.7, 24.7, and 17.5% total counts bound, respectively; and specific IgG4 values 0.851, 0.818, 0.721, 1.609, 0.789, 0.617, 0.662, 0.0, 1.127, and 0.934 OD units, respectively; the microgram of protein required to produce 50% inhibition are 2.5, 3.7, 4.5, 2.4, 5, 39.8, 25.2, 25.1, 4.5, and 8.9, respectively. A 7-kDa band is present in all SVs except in those with a ‘shiny’ phenotype.Conclusions:  The SVs with a ‘shiny’ phenotype contain less allergens than the other SVs studied, as determined by in vitro tests. However, SPT results with the SVs do not differ. Genetic screens should be devised to select plants with reduced, preferably absent, allergenicity, but with a high nutritional value, and this allergenicity should be studied utilizing in vivo and in vitro tests.

Notes: Inequalities in health care provision: the relationship between contemporary policy and contemporary practice in maternity services in England Aim. The project Addressing Inequalities in Health: new directions in midwifery education and practice (Hart et al. 2001) was commissioned by the English National Board for Nursing, Midwifery and Health Visiting (ENB). Here, we draw on those research findings to consider current midwifery policy and practice in England. Background. Little guidance on providing equality of care exists for midwives. The Code of Conduct [United Kingdom Central Council for Nursing, Midwifery and Health Visiting (UKCC) 1992] makes no specific requirement for midwives to address issues of inequalities of health in their practice. Recent policy documents emphasize the need to work towards reducing inequalities and to target practice to `disadvantaged clients' without giving guidelines on how to identify and care for target groups. Methods. In-depth studies of midwifery education and service provision were conducted in three very different parts of England. Three months of fieldwork were undertaken at each site, comprising a series of interviews with midwifery educators, managers, students, midwives and service users. Focus groups were also held and observation of classroom sessions and midwifery practice undertaken. Findings. A lack of clear and specific strategies concerning inequalities in health was evident at managerial level. Patchy knowledge of current policy was also evident amongst practising midwives. Specific projects with disadvantaged clients usually resulted from a particular midwife's personal interest or evident local need. All midwives emphasized the importance of `equality of care'. How this was operationalized varied, and `individualized' or `woman-centred' care was assumed to encompass the concept. In the few examples where care was systematically targeted in accordance with policy directives, the midwife's public health role was increased. Conclusion. In the absence of a co-ordinated strategic vision driven by managers, practitioners find difficulty in prioritizing care and targeting resources to disadvantaged clients in line with policy directives. Tensions between policy and practice in the care of `disadvantaged' women clearly exist. Successful implementation of policy at practice level needs: commitment from managers; clarity of purpose in documentation; and provision of specific targets for practitioners. However, the latter should remain flexible enough for the delivery of care to be appropriate and sensitive to individual needs.