Dot-enzyme-linked immunosorbent assay (Dot-ELISA) for detection of pneumococcal polysaccharide antigens in pleural fluid effusion samples.: Comparison with bacterial culture, counterimmunoelectrophoresis and latex agglutination

A dot-enzyme-linked immunosorbent assay (Dot-ELISA) for pneumococcal antigen detection was standardized in view of the need for a rapid and accurate immunodiagnosis of acute pneumococcal pneumonia. A total of 442 pleural fluid effusion samples (PFES) from children with clinical and laboratory diagnoses of acute bacterial pneumonia, plus 38 control PFES from tuberculosis patients and 20 negative control serum samples from healthy children were evaluated by Dot-ELISA. The samples were previously treated with 0.1 M EDTA pH 7.5 at 90°C for 10 min and dotted on nitrocellulose membrane. Pneumococcal omniserum diluted at 1:200 was employed in this assay for antigen detection. When compared with standard bacterial culture, counterimmunoelectrophoresis and latex agglutination techniques, the Dot-ELISA results showed relative indices of 0.940 to sensitivity, 0.830 to specificity and 0.760 to agreement. Pneumococcal omniserum proved to be an optimal polyvalent antiserum for the detection of pneumococcal antigen by Dot-ELISA. Dot-ELISA proved to be a practical alternative technique for the diagnosis of pneumococcal pneumonia.

Bacterial antigen detection in cerebrospinal fluid by the latex agglutination test

Eighty purulent cerebrospinal fluid (CSF) samples from patients with clinical evidence of meningitis were studied using the Directigen latex agglutination (LA) kit to determine the presence of bacterial antigen in CSF. The results showed a better diagnostic performance of the LA test than bacterioscopy by Gram stain, culture and counterimmunoelectrophoresis (CIE), as far as Neisseria meningitidis groups B and C, and Haemophilus influenzae type b are concerned, and a better performance than bacterioscopy and culture considering Streptococcus pneumoniae. Comparison of the results with those of culture showed that the LA test had the highest sensitivity for the Neisseria meningitidis group C. Comparing the results with those of CIE, the highest levels of sensitivity were detected for N. meningitidis groups B and C. Regarding specificity, fair values were obtained for all organisms tested. The degree of K agreement when the LA test was compared with CIE exhibited better K indices of agreement for N. meningitidis groups B and C.

A rapid latex agglutination test for the detection of anti-cysticercus antibodies in cerebrospinal fluid (CSF)

Simple and rapid latex-based diagnostic tests have been used for detecting specific antigens or antibodies in several diseases. In this article, we present the preliminary results obtained with a latex agglutination test (LAT) for diagnosing neurocysticercosis by detection of antibodies in CSF. A total of 43 CSF samples were assayed by the LAT: 19 CSF samples from patients with neurocysticercosis and 24 CSF samples from patients with other neurologic disorders (neurosyphilis, n = 8; neurotoxoplasmosis, n = 3; viral meningitis, n = 4, chronic headache, n = 9). The LAT exhibited 89.5% sensitivity and 75% specificity. The use of LAT seems to be an additional approach for the screening of neurocysticercosis with advantage of simplicity and rapidity. Further studies could be performed using purified antigens and serum samples.

Risk Factors for Latex Sensitization in Children with Spina Bifida

Background: Children with spina bifida represent the major risk group for latex sensitization. Purpose: To determine the prevalence of latex sensitization in these children and to identify risk factors. Material and methods: We studied 57 patients with spina bifida. The mean age was 5.6 years and the male/female ratio was 0.8/1. In all patients a questionnaire, skin prick test (SPT) with latex (UCBStallergènes, Lofarma and ALK-Abelló), common aeroallergens and fruits (UCB-Stallergènes) and serum determination of total IgE (AlaSTAT) were performed. Results: The prevalence of latex sensitization was 30 %; only two sensitized children (12 %) had symptoms after exposure. Risk factors for latex sensitization were age 5 years (p = 0.008; OR = 6.0; 95% CI = 1.7-22.1), having at least four previous surgical interventions (p < 0.0001; OR = 18.5; 95% CI = 3.6-94.8), having undergone surgery in the first 3 months of life (p = 0.008; OR = 5.4; 95% CI = 0.7-29.2) and total serum IgE 44 IU/ml (p = 0.03; OR = 3.8; 95 %CI = 1.1-13.1). Multiple logistic regression analysis showed that only a history of four or more surgical interventions (p < 0.0001; OR = 26.3; 95 %CI = 2.9-234.2) and total serum IgE 44 IU/ml (p = 0.02; OR = 8.6; 95% CI = 1.4-53.4) were independently associated with latex sensitization. Sex, family and personal allergic history, hydrocephalus with ventriculoperitoneal shunt, cystourethrograms, intermittent bladder catheterization and atopy were not related to latex sensitization. Conclusions: In children with spina bifida, significant and independent risk factors identified for latex sensitization were multiple interventions and higher levels of total serum IgE. A prospective study will clarify the clinical evolution of assymptomatic children sensitized to latex.

Efficacy of euphorbia hirta latex as plant derived molluscicides against freshwater snails

The toxic effect of binary and tertiary combinations of Euphorbia hirta Linn latex powder with other plant molluscicidal compounds, were evaluated against the freshwater snails Lymnaea (Radix) acuminata and Indoplanorbis exustus in pond. These combinations showed significant time and dose dependent effect against both the snails. These compounds at higher doses were also lethal to freshwater fish Channa punctatus (Bloch) (Channidae {Ophicephalidae}), which shares the habitat with these snails, but the LC90 (24h) doses of snails have no apparent killing properties in fish populations when treated in mixed population of snails and fish.

Comparação entre o reagente Chagas-latex e a imunofluorescência no diagnóstico sorológico da doença de Chagas na zona sul do Rio Grande do Sul

Os Autores submeteram 142 amostras de soros de casos agudos e crônicos de Doença de Chagas, já examinados com o Reagente Chagas-Latex, ao exame de Imunofluorescência, obtendo correspondência de resultados em 139 (97,9%). O alto índice de fidelidade, provavelmente devido à ausência na zona de doenças que possam proporcionar resultados falsamente positivos, fez do Reagente Chagas-Latex um método simples e fácil para a triagem sorológica nos casos suspeitos em zona endêmica.

Different in Vivo Reactivity Profile in Health Care Workers and Patients with Spina Bifida to Internal and External Latex Glove Surface-Derived Allergen Extracts

BACKGROUND: Allergy to natural rubber latex is a well-recognized health problem, especially among health care workers and patients with spina bifida. Despite latex sensitization being acquired in health institutions in both health care workers and patients with spina bifida, differences in allergen sensitization profiles have been described between these two risk groups. OBJECTIVE: To investigate the in vivo reactivity of health care workers and patients with spina bifida to extracts of internal and external surfaces of latex gloves and also to specific extracts enriched in major allergens for these risk groups. METHODS: Gloves from different manufacturers were used for protein extraction, and salt precipitation and hydrophobic interaction chromatography (HIC) were applied to obtain the enriched latex extracts. The major latex allergens were quantified by an enzyme immunoassay. The extracts obtained were tested in 14 volunteers using skin prick tests (SPT). RESULTS: Latex glove extracts enriched in the hydrophobic allergens that are most often seen in patients with spina bifida were obtained by selective precipitation, whereas HIC produced extracts enriched in the hydrophilic allergens commonly found in health care workers. The health care workers had positive SPTs to glove extracts from internal surfaces and to the hydrophilic allergen-enriched extracts. By contrast, patients with spina bifida had larger skin reactions both to external glove extracts and to the extracts enriched with the hydrophobic major allergens for this risk group. Despite the protein concentration of these extracts being less than half the concentration of the commercial extract, the weal-and-flare reactions were of similar magnitude. CONCLUSION: Using novel latex extracts, our study showed a different in vivo reactivity pattern in health care workers and in patients with spina bifida to extracts of the internal and external surfaces of gloves, which suggests that sensitization may occur by different routes of exposure, and that this influences the allergen reactivity profiles of these risk groups

Quantitative Analysis of Immunoglobulin E Reactivity Profiles in Patients Allergic or Sensitized to Natural Rubber Latex (Hevea Brasiliensis)

Characterized native and recombinant Hevea brasiliensis (rHev b) natural rubber latex (NRL) allergens are available to assess patient allergen sensitization profiles. OBJECTIVE: Quantification of individual IgE responses to the spectrum of documented NRL allergens and evaluation of cross-reactive carbohydrate determinants (CCDs) for more definitive diagnosis. METHODS: Sera of 104 healthcare workers (HCW; 51 German, 21 Portuguese, 32 American), 31 spina bifida patients (SB; 11 German, 20 Portuguese) and 10 Portuguese with multiple surgeries (MS) were analysed for allergen-specific IgE antibody (sIgE) to NRL, single Hev b allergens and CCDs with ImmunoCAP technology. RESULTS: In all patient groups rHev b 5-sIgE concentrations were the most pronounced. Hev b 2, 5, 6.01 and 13 were identified as the major allergens in HCW and combined with Hev b 1 and Hev b 3 in SB. In MS Hev b 1 displayed an intermediate relevance. Different sIgE antibody levels to native Hevea brasiliensis (nHev b) 2 and rHev b 6.01 allowed discrimination of SB with clinical relevant latex allergy vs. those with latex sensitization. Sensitization profiles of German, Portuguese and American patients were equivalent. rHev b 5, 6.01 and nHev b 13 combined detected 100% of the latex-allergic HCW and 80.1% of the SB. Only 8.3% of the sera showed sIgE response to CCDs. CONCLUSIONS: Hev b 1, 2, 5, 6.01 and 13 were identified as the major Hev b allergens and they should be present in standardized latex extracts and in vitro allergosorbents. CCDs are only of minor relevance in patients with clinical relevant latex allergy. Component-resolved diagnostic analyses for latex allergy set the stage for an allergen-directed immunotherapy strategy

Flow cytometric quantitation of phagocytosis in heparinized complete blood with latex particles and Candida albicans

We report a rapid method for the flow cytometric quantitation of phagocytosis in heparinized complete peripherial blood (HCPB), using commercially available phycoerythrin-conjugated latex particles of 1µm diameter. The method is faster and shows greater reproducibility than Bjerknes' (1984) standard technique using propidium iodide-stained Candida albicans, conventionally applied to the leukocytic layer of peripherial blood but here modified for HCPB. We also report a modification of Bjerknes' Intracellular Killing Test to allow its application to HCPB.

Contribution to the study of Himatanthus sucuuba: latex macromolecule, microelements and carbohydrates

The polymeric material in the latex of Himatanthus sucuuba (Spruce) Woodson was identified by spectroscopic methods as cis-polyisoprene (Mn = 192; Mw = 571; Mw/ Mn = 2.97). ICP-MS analysis of microelements in the aqueous phase showed the most abundant to be Ca (354 μg/g) and Mg (250 μg/g). Carbohydrate analysis of the aqueous phase by HPLC-PAD showed arabinose, glucose, xylose, rhamnose and galactose to be the predominant saccharides.

Quantitative determination by HPLC of iridoids in the bark and latex of himatanthus sucuuba

The main iridoids from the bark and latex of Himatanthus sucuuba were isolated and characterised by spectroscopic methods. HPLC was used for the quantitative analyses of these iridoids and the chromatograms of bark and latex showed a similar iridoid composition. Both parts of the plant are used in folk medicine for the treatment of various ailments.

Produção de latex por clones de seringueira (Hevea spp) no planalto e litoral do Estado de São Paulo

A partir dos dados de produção em volume de látex, extraído de clones de seringueira (Hevea spp.), durante 17 anos no Centro Experimental Theodureto de Camargo (Campinas, região de planalto) e 16 anos na Estação Experimental Vale do Ribeira (Pariquera-Açú, região litorânea), ambos pertencentes ao Instituto Agro_ nômico do Estado de São Paulo, Campinas, foi estudado o comportamento da produção de cada clone. Pelo teste de Tukey foi possível determinar, considerando-se as duas regiões, os melhores clones quanto ao potencial produtivo dado pelas médias de produção. Entre os melhores encontram-se: RRIM 600 e BSA 20. 0 primeiro pertence a Estação Experimental e o segundo ao Centro Experimental. Em seguida tem-se um grupo intermediário, formado pelos clones CA 1328, Tjir 16, C 228, RRIm 526, C 297, LCB 510 e Fx 25, todos pertencentes ao Centro Experimental. Os menos produtivos foram: Fx 25, C 290 e RRIM 600, todos pertencentes ao Centro Experimental. 0 clone Fx 25 apresentou baixa produção nas regiões estudadas, porém sua produção na Estação Experimental foi superior à do Centro Experimental, bem como às dos clones C 290 e RRIM 600, cultivados no Centro Experimental.

Latex of "Coroa de Cristo" (Euphorbia Splendens): an effective molluscicide

An aqueous solution of the latex of "coroa de cristo" (Euphorbia splendens var. hislopii) showed molluscicide action (LD90) at a concentration lower than 0.5 ppm on Biomphalaria glabrata and B. tenagophila reared in laboratory and at a concentration lower than 4.0 ppm for field B. tenagophila.

Toxicological study of the molluscicidal latex of Euphorbia splendens: irritant action on skin and eye

Aqueous solutions of the molluscicidal latex of Euphorbia splendens are irritant to the rabbit eye in concentrations higher than 0.35% and to the rabbit skin in concentrations higher than 0.5%. Although this irritant potential does not proclude its use as a molluscicide, special precautions are recommended for hanbdling and application of the product and the hazard of skin tumor-promoting potencial should be carefully investigated before its use for schistosomiasis vector control.