Impact of climate change-related environmental factors on the allergens production and the epidemiology and severity of allergic pathologies.

BACKGROUND: Allergic disease affects up to 40% of the global adult population, a proportion that is increasing with environmental changes related to global warming. METHODS: We undertook a systematic review of the literature to identify and evaluate the current evidence of the impact of climate change-related environmental factors on the allergen production and the epidemiology and severity of allergic pathologies. PECO criteria were established and guided the literature searches of the PubMed and Cochrane databases (Jan 1, 2016 to Dec 31, 2021). Study outcomes were categorized and grouped to facilitate data synthesis. Outcomes were classified as significant (statistical significance <0.05), non-significant (p>0.05) or undetermined (p value not reported). Study quality was assessed using MMAT analysis. RESULTS: Of 195 studies, 40 were considered relevant and 9 of them provided data to be included in the data quantitative synthesis. Environmental factors, including the presence of pollutants, temperature, and drought, influenced the type, volume, and timing of exposure to local aeroallergens. The most relevant environmental factor was the presence of environmental pollutants, of which tropospheric ozone was the most frequently associated to changes in allergen production, prevalence, and severity of allergic disease. Also, several publications demonstrated the impact of environmental factors on the healthcare burden. CONCLUSIONS: Climate-change related environmental factors increased allergic disease in terms of prevalence, severity, and healthcare burden due to alterations in allergen exposure (volume and type) with the presence of pollutants such as ozone being the most commonly reported driver of such increase.

Onset of Nut Allergy in a Pediatric Cohort: Clinical and Molecular Patterns in the AFRUSEN Study.

BACKGROUND AND OBJECTIVE: Nut allergy is a growing problem, yet little is known about its onset in children. Objective: To characterize the onset of nut allergy in children in southern Europe. METHODS: The study population comprised consecutive patients up to 14 years of age who visited allergy departments with an initial allergic reaction to peanut, tree nut, or seed. The allergy work-up included a clinical history, food challenge, skin prick testing, determination of whole-extract sIgE, and ImmunoCAP ISAC-112 assay. RESULTS: Of the 271 children included, 260 were first diagnosed with nut allergy at a mean age of 6.5 years and at a mean (SD) of 11.8 (21.2) months after the index reaction. The most common culprit nuts at onset were walnut (36.5%), peanut (28.5%), cashew (10.4%), hazelnut (8.5%), pistachio (5.4%), and almond (5%). Onset of peanut allergy was more frequent in children ≤6 years and walnut in those aged >6 years (P=.032). In 65% of cases, the allergic reaction occurred the first time the patient consumed the nut, and 35% of reactions were anaphylactic. Overall, polysensitization to nuts was detected by skin prick testing in 64.9% of patients, although this rate was lower among walnut-allergic children (54.7%) and peanut-allergic children (54.1%) (P<.0001). Sensitization to 2S albumins was predominant (75%), especially Jug r 1 (52.8%), whereas sensitization to lipid transfer proteins was less relevant (37%). CONCLUSION: In the population we assessed, the onset of nut allergy occurred around 6 years of age, slightly later than that reported in English-speaking countries. Walnut was the main trigger, followed by peanut. 2S albumin storage proteins, especially Jug r 1, were the most relevant allergens. This study will help guide management and may contribute to preventive strategies in pediatric nut allergy.

Lipopeptide production by Serratia marcescens SmSA using a Taguchi design and its application in enhanced heavy oil recovery.

Biosurfactant production at reactor level by Serratia marcescens SmSA was optimized and evaluated to enhance the heavy oil recovery on carbonate rocks. Temperature, agitation, and carbon/nitrogen (C/N) ratio were evaluated to optimize biosurfactant production by using a Taguchi (L9) design. The best conditions (C/N ratio: 6, 25 °C, and agitation: 100 rpm) were used to scale up the biosurfactant production with a 3-L bioreactor. The best aeration for biosurfactant production was 0.66 volume of air per volume of liquid per minute (vvm), producing the lowest surface tension (26 mN/m) in 14 h, with a biosurfactant yield of 14.26 g/L as a crude product and 2.85 g/L as a purified product, and a critical micelle concentration of 280 mg/L. The biosurfactant was characterized as a lipopeptide, and it was stable under extreme conditions: pH (2-12), salinity up to 200 g/L, and temperature up to 150 °C confirmed by thermogravimetric analysis. Enhanced oil recovery test was carried out with a carbonate core and heavy oil under reservoir conditions, obtaining an additional recovery of 8%, due to reduced interfacial tension and modified wettability of the rock. These findings highlight the potential application of S. marcescens SmSA biosurfactant in enhanced oil recovery.

A pathway-based association study reveals variants from Wnt signalling genes contributing to asthma susceptibility.

BACKGROUND: Genetic susceptibility to asthma is currently linked to a handful of genes which have a limited ability to predict the overall disease risk, suggesting the existence of many other genes involved in disease development. Accumulated evidence from association studies in genes related by biological pathways could reveal novel asthma genes. OBJECTIVE: To reveal novel asthma susceptibility genes by means of a pathway-based association study. METHODS: Based on summary data from a previous a genomewide association study (GWAS) of asthma, we first identified significant biological pathways using a gene-set enrichment analysis. We then mapped all tested single nucleotide polymorphisms (SNPs) on the genes contributing to significant pathways and prioritized those with a disproportionate number of nominal significant associations for further studies. For those prioritized genes, association studies were performed for selected SNPs in independent case-control samples (n = 1765) using logistic regression models, and results were meta-analysed with those from the GWAS. RESULTS: Two biological processes were significantly enriched: the cytokine-cytokine receptor interaction (P = 0.002) and the Wnt signalling (P = 0.012). From the 417 genes interacting in these two pathways, 10 showed an excess of nominal associations, including a known asthma susceptibility locus (encoding SMAD family member 3) and other novel candidate genes. From the latter, association studies of 14 selected SNPs evidenced replication in a locus near the frizzled class receptor 6 (FZD6) gene (P = 9.90 × 10-4 ), which had a consistent direction of effects with the GWAS findings (meta-analysed odds ratio = 1.49; P = 5.87 × 10-6 ) and was in high linkage disequilibrium with expression quantitative trait loci in lung tissues. CONCLUSIONS AND CLINICAL RELEVANCE: This study revealed the importance of two biological pathways in asthma pathogenesis and identified a novel susceptibility locus near Wnt signalling genes.

Tolerability during double-blind randomized phase I trials with the house dust mite allergy immunotherapy tablet in adults and children.

BACKGROUND AND OBJECTIVE: The orodispersible house dust mite (HDM) sublingual immunotherapy (SLIT)-tablet (ALK, Denmark) is being developed for the treatment of HDM respiratory allergic disease. The objective of the 2 phase I trials was to investigate tolerability and the acceptable dose range of HDM SLIT-tablet treatment in adults and children with HDM respiratory allergic disease. PATIENTS AND METHODS: The trials were randomized, multiple-dose, dose-escalation, double-blind, placebo-controlled phase I trials including patients with HDM-induced asthma, with or without rhinoconjunctivitis. Both trials were registered in EudraCT (Trial 1: 2005-002151-41; Trial 2: 2007-000402-67). Trial 1 included 71 adults (18-63 years) and trial 2 included 72 children (5-14 years). Both trials included 6 dose groups that were randomized 3:1 to active treatment or placebo once daily for 28 days. Adverse events (AEs) were coded in MedDRA (version 8.1 or later). Immunological variables included specific IgE and IgE-blocking factor. RESULTS: No serious AEs were reported. In trial 1 (maximum dose, 32 development units [DU]), 1 patient in the 16 DU group discontinued due to AEs. The entire 32 DU group was discontinued as 1 patient had a severe adverse reaction. In trial 2 (maximum dose, 12 DU), no patients discontinued prematurely. The most frequently reported AEs were mild application-site related events. The total number of events was dose-related within each trial. HDM SLIT-tablet treatment induced changes in immunological parameters in a dose-dependent manner. CONCLUSIONS: These trials demonstrate that doses up to 12 DU of HDM SLIT-tablet were tolerated in the selected populations, and thus are suitable for further clinical investigations in adults and children with HDM respiratory allergic disease.

Analysis of mite allergic patients in a diverse territory by improved diagnostic tools.

BACKGROUND: There are few studies comparing the sensitization with mite allergens from different mite species which could potentially be the cause of allergy. OBJECTIVE: To improve the diagnosis of mite allergic patients from a diverse territory in which D. pteronyssinus/D. farinae mites together with storage mites could be present in the environment. METHODS: Four hundred and seventy-seven patients (both children and adults) from different regions, covering the main mite prevalent areas of Spain, were recruited. sIgE to eight allergens was measured together with SPT to whole mite extracts, level of mite allergen exposure, and specific IgG(4) . BAT and CAST was performed in a subgroup of patients. RESULTS: D. pteronyssinus and L. destructor were more prevalent in Atlantic areas, whereas D. farinae predominate in Mediterranean areas. About 90% of patients were sensitized to group 1 and/or group 2 allergens. Group 2 was the most prevalent, and the IgE response/intensity of sensitization in BAT was higher. sIgE to Der p 2/Der f 2 was almost fully cross-reactive, but no cross-reactivity was detected with Lep d 2. Group 1 allergens were also cross-reactive, but in some patients a species-specific response was observed. sIgE to Lep d 2 was associated with SPT results to storage mites. Sensitization to Der p 1 was more frequent in children, whereas Lep d 2 sensitization was more frequent in adults. A higher ratio IgE/IgG(4) to Der p 2 was associated with the presence of allergic asthma. CONCLUSION: An improved diagnosis algorithm has been established. Group 2 allergens seem to have a leading role in mite allergy, but as group 1 sensitization could be species-specific in some patients and its prevalence is higher in children, an adequate balance on major mite species and major allergens must be consider in the design of mite allergy vaccines.

Aerobic biodegradation of sludge with high hydrocarbon content generated by a Mexican natural gas processing facility.

The biodegradation of oil sludge from Mexican sour gas and petrochemical facilities contaminated with a high content of hydrocarbons, 334.7 ± 7.0 g kg(-1) dry matter (dm), was evaluated. Studies in microcosm systems were carried out in order to determine the capacity of the native microbiota in the sludge to reduce hydrocarbon levels under aerobic conditions. Different carbon/nitrogen/phosphorous (C/N/P) nutrient ratios were tested. The systems were incubated at 30 °C and shaken at 100 rpm. Hydrocarbon removals from 32 to 51% were achieved in the assays after 30 days of incubation. The best assay had C/N/P ratio of 100/1.74/0.5. The results of the Microtox(®) and Ames tests indicated that the original sludge was highly toxic and mutagenic, whereas the best assay gave a final product that did not show toxicity or mutagenicity.

Evaluation of haloalkaliphilic sulfur-oxidizing microorganisms with potential application in the effluent treatment of the petroleum industry.

Haloalkaliphilic sulfur-oxidizing mixed cultures for the treatment of alkaline-saline effluents containing sulfide were characterized and evaluated. The mixed cultures (IMP-PB, IMP-XO and IMP-TL) were obtained from Mexican alkaline soils collected in Puebla (PB), Xochimilco (XO) and Tlahuac (TL), respectively. The Ribosomal Intergenic Spacer Analysis (RISA) revealed bacteria related to Thioalkalibacterium and Thioalkalivibrio in IMP-XO and IMP-PB mixed cultures. Halomonas strains were detected in IMP-XO and IMP-TL. In addition, an uncultured Bacteroides bacterium was present in IMP-TL. Mixed cultures were evaluated at different pH and NaCl concentrations at 30°C. IMP-PB and IMP-TL expressed thiosulfate-oxidizing activity in the 7.5-10.5 pH range, whereas IMP-XO presented its maximal activity with 19.0 mg O2 g (protein)⁻¹ min⁻¹, at pH 10.6; it was not affected by NaCl concentrations up to 1.7 M. In continuous culture, IMP-XO showed a growth rate of 15 day⁻¹, productivity of 433.4 mg(protein) l⁻¹ day⁻¹ and haloalkaliphilic sulfur-oxidizing activity was also detected up to 170 mM by means of N-methyl-diethanolamine (MDEA). Saline-alkaline soil samples are potential sources of haloalkaliphilic sulfur-oxidizing bacteria and the mixed cultures could be applied in the treatment of inorganic sulfur compounds in petroleum industry effluents under alkaline-saline conditions.

5-Lipoxygenase pathway gene polymorphisms: lack of association with asthma in a Spanish population.

BACKGROUND: Cysteinyl-leukotrienes are mediators of inflammatory responses in bronchial asthma. We studied the genes encoding the enzymes involved in their synthesis to identify risk factors for asthma. The promoter polymorphisms LTC4S -444 A/C, ALOX5 -176/-147, and ALOX5AP -169/-146 have been reported to be associated with bronchial asthma. METHODS: We analyzed the effects of LTC4S -444 A/C, ALOX5 -176/-147, and ALOX5AP -169/-146 on asthma susceptibility by means of a case-control study with 193 ethnically matched, unrelated individuals. Participants were classified as severe asthmatics, nonsevere asthmatics, and nonasthmatics, using a combination of 2 techniques: polymerase chain reaction-restricted fragment length polymorphism and multiplex capillary electrophoresis. RESULTS: No association was found between these polymorphisms and asthma, neither individually nor in combination. CONCLUSION: Although the studied polymorphisms have been previously reported to constitute risk factors for the disease, we found no association between LTC4S -444 A/C, ALOX5 -176/-147, and ALOX5AP -169/-146 polymorphisms and bronchial asthma.

Immunoglobulin E recognition patterns to purified Kiwifruit (Actinidinia deliciosa) allergens in patients sensitized to Kiwi with different clinical symptoms.

BACKGROUND: Green kiwifruit allergy is on the rise. However, no surveys testing purified major kiwi allergens have been carried out in a large population, including both kiwi-sensitized [skin prick test (SPT)-positive] and truly kiwi-allergic patients. OBJECTIVE: To isolate major kiwifruit allergens, and to explore their relevance by in vitro and in vivo methods in a large kiwi-sensitized and -allergic population. METHODS: A large group (n=92) of kiwi-sensitized patients with different clinical symptoms were selected, and double-blind, placebo-controlled, food challenges to kiwi were performed in 52 of them. The three major IgE-binding proteins from kiwifruit extracts were isolated and characterized by N-terminal amino acid sequencing and molecular size and glycosylation analysis. The allergenic potency of the three kiwi allergens, and of avocado Pers a 1 as a model allergen associated with the latex-fruit syndrome, was tested by specific IgE quantitation, immunodetection assays and SPTs. RESULTS: The isolated kiwifruit allergens were identified as actinidin Act d 1, glycosylated thaumatin-like Act d 2 and a novel 40 kDa glycoprotein designated as Act d 3.02. Specific IgE to each of the three allergens was found in over 60% of sera from kiwi-sensitized patients, and Act d 1 and Act d 2 induced positive SPT responses in over 50% of the tested patients. A significant link between IgE levels to Act d 1 and Act d 3 and anaphylaxis was uncovered. Avocado Pers a 1 showed an in vitro sensitization prevalence of around 45%, but a low in vivo reactivity. CONCLUSION: Act d 1, Act d 2 and Act d 3 are major allergens in the population studied. Severe symptoms after kiwi ingestion are associated with high IgE levels to Act d 1 and Act d 3.

Challenge-based clinical patterns of 223 Spanish patients with nonsteroidal anti-inflammatory-drug-induced-reactions.

BACKGROUND: The single-blind, placebo controlled oral challenge (SBPCOC) is the definitive way to diagnosis nonsteroidal anti-inflammatory drug (NSAID)-induced reactions. OBJECTIVE: To evaluate 223 NSAID-sensitive patients by means of SBPCOC, and to describe the main clinical patterns found. METHODS: A prospective study was carried out, including 2 patient groups with case histories consistent with NSAID-induced reactions. Of the 223 patients, 174 were diagnosed on the basis of a positive SBPCOC. The second group consisted of 49 patients who were referred because of a documented history of anaphylaxis after taking NSAIDs, and these underwent SBPCOC with potent cyclooxygenase (COX)-1/COX-2 inhibitors, except those reported as being responsible for the reaction. The type of SBPCOC reaction, the NSAID reactivity pattern, and the associated diseases were the main classification criteria. RESULTS: Two broad categories of NSAID-induced reactions were identified: the cross-reactive and selective syndromes. The 150 patients who showed cross-reactive syndromes included 3 types of diseases: type 1, patients with rhinitis and/or asthma who developed nasoocular and/or asthmatic reactions (n=40); type 2, patients with or without chronic urticaria who presented urticaria/angioedema (n=59); and type 3, atopic patients with isolated periorbital angioedema (n=51). In contrast, the selective syndromes, or type 4, included 50 patients who developed anaphylaxis, as well as 11 patients with urticaria during SBPCOC. Finally, a miscellaneous group of reactions not matching any of the above types was identified (n=1 2). CONCLUSIONS: NSAID-sensitive patients can be classified into 4 different groups of reactors, each with well-defined clinical characteristics. Thus, a clinical classification of this NSAID-induced reaction complex is proposed.

A field trial for an ex-situ bioremediation of a drilling mud-polluted site.

The remediation of drilling mud-polluted sites in the Southeast of Mexico is a top priority for Mexican oil industry. The objective of this work was to find a technology to remediate these sites. A field trial was performed by composting in biopiles, where four 1ton soil-biopiles were established, one treatment in triplicate and one unamended biopile. Amended biopiles were added with nutrients to get a C/N/P ratio of 100/3/0.5 plus a bulking agent (straw) at a soil/straw ratio of 97/3. Moisture content was maintained around 30-35%. Results showed that, after 180 d, total petroleum hydrocarbon (TPH) concentrations decreased from 99300+/-23000mgTPHkg(-1) soil to 5500+/-770mgTPHkg(-1) for amended biopiles and to 22900+/-7800mgTPHkg(-1) for unamended biopile. An undisturbed soil control showed no change in TPH concentrations. Gas chromatographic analysis showed residual alkyl dibenzothiophene type compounds. Highest bacterial counts were observed during the first 30 d which correlated with highest TPH removal, whereas fungal count increased at the end of the experimentation period. Results suggested an important role of the straw, nutrient addition and water content in stimulating aerobic microbial activity and thus hydrocarbon removal. This finding opens an opportunity to remediate old polluted sites with recalcitrant and high TPH concentration.

Hallazgo Incidental de Tumor Estromal Gastrointestinal en Divertículo de Meckel. Caso Clínico

Introducción: El divertículo de Meckel es un defecto sacular ubicado en el íleon distal, con una tasa de complicaciones de 4%. La resección quirúrgica está indicada en estas complicaciones, siendo controversial en casos asintomáticos o incidentales. Dentro de las complicaciones existen tumores como los estromales gastrointestinales (GIST). Caso Clínico: Hombre de 57 años, postrado por múltiples factores, presenta úlcera por presión sacra grado IV sobreinfectada y con evolución tórpida. Se decide realizar colostomía terminal, evidenciando un divertículo de Meckel en el intraoperatorio con aspecto sospechoso, por lo cual se decide resecar, resultando en un GIST de bajo riesgo. Se mantiene en seguimiento por 6 meses, sin recidiva tumoral. Discusión: Mientras que la cirugía pareciera ser imperativa en complicaciones, aún existe debate respecto a las indicaciones de resección de divertículo de Meckel hallado incidentalmente en el intraoperatorio por cirugía de otra causa. Si bien puede aumentar la morbimortalidad, la resección estaría indicada según ciertas características como edad, sexo, tamaño y aspecto, dado el riesgo de desarrollo de complicaciones y neoplasias.

Introduction: Meckel's diverticulum is a saccular defect located in the distal ileum, with a complication rate of 4%. Surgical resection is indicated when these complications occur, yet resection in asymptomatic or incidental cases remains controversial. Among these complications, the appearance of tumors such as gastrointestinal stromal (GIST), may occur. Case Report: A 57-year-old male, bedridden due to multi- ple factors, presents with a complicated grade IV sacral pressure ulcer with a torpid evolution. An end colostomy is performed, evidencing a suspicious-looking Meckel's diverticulum intraoperatively, which was resected and resulted to be a low-risk GIST. At a 6-month follow-up, the patient showed no evidence of tumor recurrence. Discussion: While surgery seems to be imperative in complications, there is still a debate regarding the indications for resection of Meckel's diverticulum found incidentally intraoperatively due to surgery for another cause. Although it could increase morbidity and mortality, resection could be indicated according to certain characteristics such as age, sex, size and appearance, given the risk of developing complications and neoplasm.

COVID 19 y embarazo en Chile: Informe preliminar del estudio multicéntrico GESTACOVID / COVID-19 and pregnancy in Chile: preliminary report of the GESTACOVID multicenter study

INTRODUCCIÓN: En Chile, los efectos maternos y perinatales de la pandemia por SARS-CoV-2 son aún desconocidos. GESTACOVID es un estudio multicéntrico que incluye embarazadas y puérperas hasta el día 42 con COVID-19. El objetivo de este estudio es presentar un informe preliminar, describiendo el impacto de la enfermedad en las embarazadas, factores de riesgo asociados y resultados perinatales. MÉTODOS: Estudio de cohorte descriptivo que incluye 661 pacientes enroladas entre el 7 de marzo y el 6 de julio de 2020, en 23 centros hospitalarios del país. Se analizaron variables demográficas, comorbilidades, características clínicas y del diagnóstico de COVID-19 y resultado materno y perinatal. RESULTADOS: Las pacientes hospitalizadas por COVID-19 tuvieron mayor prevalencia de hipertensión arterial crónica [10% vs 3%; OR=3,1 (1,5-6,79); p=0,003] y de diabetes tipo 1 y 2 [7% vs 2%; OR=3,2 (1,3-7,7); p=0,009] que las pacientes manejadas ambulatoriamente. Un IMC >40 kg/mt2 se asoció con un riesgo dos veces mayor de requerir manejo hospitalizado [OR=2,4 (1,2 - 4,6); p=0,009]. Aproximadamente la mitad de las pacientes (54%) tuvo un parto por cesárea, y un 8% de las interrupciones del embarazo fueron por COVID-19. Hasta la fecha de esta publicación, 38% de las pacientes continuaban embarazadas. Hubo 21 PCR positivas en 316 neonatos (6,6%), la mayoría (17/21) en pacientes diagnosticadas por cribado universal. CONCLUSIONES: Las embarazadas con COVID-19 y comorbilidades como diabetes, hipertensión crónica y obesidad mórbida deben ser manejadas atentamente y deberán ser objeto de mayor investigación. La tasa de transmisión vertical requiere una mayor evaluación para diferenciar el mecanismo y tipo de infección involucrada.

INTRODUCTION: In Chile, effects of the SARS-CoV-2 infection in pregnant women are unknown. GESTACOVID is a multicenter collaborative study including pregnant women and those in the postpartum period (until 42 days) who have had COVID-19. The purpose of this study is to report our preliminary results describing the clinical impact of COVID-19 in pregnant women, the associated risk factors and perinatal results. METHODS: Descriptive cohort study including 661 patients between April 7th and July 6th, 2020, in 23 hospitals. Demographical, comorbidities, clinical and diagnostic characteristics of COVID-19 disease and maternal and perinatal outcomes were analyzed. RESULTS: Pregnant women with COVID-19 admitted to the hospital were more likely to have chronic hypertension [10% vs 3%; OR=3.1 (1.5-6.79); p=0,003] and diabetes type 1 and 2 [7% vs 2%; OR=3.2 (1.3-7.7); p=0.009] than those with outpatient management. A body mass index of >40 kg/mt2 was associated with two-fold higher risk of hospitalization [OR=2.4 (1.2-4.6); p=0.009]. Almost half of patients (54%) were delivered by cesarean section, and 8% of the medically indicated deliveries were due to COVID-19. So far, 38% of the patients are still pregnant. Among 316 newborns, there were 21 positive PCR tests (6.6%), mostly from asymptomatic mothers undergoing universal screening. CONCLUSIONS: Pregnant women with COVID-19 and comorbidities such as diabetes, chronic hypertension and morbid obesity need a close follow up and should be a matter for further research. Vertical transmission of COVID-19 should be thoroughly studied to define the mechanisms and type of infection involved.

Relationships between characteristics of exposure to pigeon antigens. Clinical manifestations and humoral immune response.

An extensive clinical study has been performed on pigeon breeders in the Canary Islands. Three hundred forty-three subjects have participated in this study through the filling of a clinical and epidemiologic questionnaire. A venous blood sample was also taken from each fancier for a further serologic analysis. Detection of specific IgG antibodies was made by an indirect enzyme-linked immunosorbent assay (ELISA) using pigeon serum as antigenic material. Twenty-nine (8 percent) breeders fulfilled the "classic" pigeon breeders' disease (PBD) criteria. One hundred six (31 percent) had rhinitis, 62 (19 percent) had immediate bronchial symptoms, and 51 (15 percent) suffered from chronic bronchitis. A significant level of specific IgG was detected in 139 (40 percent) cases. Rates were correlated with pneumonitis symptomatology (p < 0.001) and with chronic bronchitis (p < 0.05). There was a significant association between the number of pigeons and the level of sensitization (p < 0.001). Finally, a statistical relationship between the intensity of exposure and specific IgG response was also found (p < 0.001). Titers of specific IgE could not be related either to the reported symptomatology in the questionnaire or to any of the exposure parameters analyzed.

Indoor allergens and dwelling characteristics in two cities in Spain.

BACKGROUND: Indoor allergens are common causes of sensitization and asthma. Climatic and home conditions can modify their levels. OBJECTIVE: We studied the influence of climatic conditions and home characteristics on the exposure to indoor allergens of mite allergic asthmatic subjects in two Spanish cities with different climates (Las Palmas and Pamplona). METHODS: We included 65 subjects diagnosed with asthma caused by Dermatophagoides pteronyssinus. A questionnaire about their dwellings was completed. Home dust samples were collected. Mite (Der p1, Der f1, Der 2) and cat (Fel d1) allergens were measured by a monoclonal-antibodies based ELISA. RESULTS: Characteristics of dwellings were similar in both areas. Der p1 was the main allergen (0-44 micrograms/g). Der p1, Der f1 and Der 2 levels were higher in the homes in Las Palmas (p < 0.001, p < 0.01 and p < 0.001, respectively). Damp homes in Pamplona had higher Der p1 levels, similar to those detected in homes in Las Palmas. Fel d1 levels (0-78.90 micrograms/g) were only related to the presence of cats in the dwelling (p < 0.001). CONCLUSIONS: D. pteronyssinus allergen exposure was influenced by climatic conditions and dampness in homes in temperate regions. Humidity in homes can generate an ideal environment for mite growth despite unfavorable outdoor climatic conditions. Fel d1 levels were only related to the presence of a cat in the house.

Starch-based plastic polymer degradation by the white rot fungus Phanerochaete chrysosporium grown on sugarcane bagasse pith: enzyme production.

In this study, starch metabolites and enzymes were determined during starch-based plastic polymer biodegradation by the white rot fungus Phanerochaete chrysosporium, grown in sugarcane bagasse pith in tubular reactors. Various metabolites, amylase, ligninase and cellulase production were measured during P. chrysosporium growth on sugarcane bagasse pith with added glucose and starch polymer. On-line respirometric analyses followed during 32 days confirmed the P. chrysosporium capability of growing on sugarcane bagasse pith with starch polymer degradation. Enzyme activity during secondary metabolism increased, and a 70% and 74% starch degradation was reached with and without glucose addition, generating low molecular weight metabolites (e.g.) dextrin, maltotriose, maltose and glucose that were detected by high performance liquid chromatography.

[Epidemiology of tuberculosis in the Gran Canary Island]. / Epidemiología de la enfermedad tuberculosa en la isla de Gran Canaria.

BACKGROUND: The aim of the present study was to obtain information about tuberculosis (TB) in our area that might contribute to assess the status in Spain. METHODS: A meticulous case finding was carried out during 1988 in all the hospitals of the Gran Canaria island. RESULTS: 214 cases were found (rate 32.2) and 77% were admitted to hospitals. In 160 (74%) the involvement was pulmonary and in 82 (37%) it was extrapulmonary. Mean age was 34 years (range 1-84) and 62% were younger than 40 years. 69% were males. Complete data were obtained in 183 cases (85%). 56% were smokers, 34% alcoholic abusers, 15% drug abusers (35% parenteral) and 4% homosexuals. 26% had some risk factor for TB; 14 of them had been infected by the HIV (8 had AIDS). In 64% there was a diagnostic delay longer than one month. Out of the 214 cases, the diagnosis was made by direct microscopy and/or culture in 110 (51%), by consistent pathological findings in 41 (19%), with some of these studies but with negative results in 35 (16%) and only with clinical and radiological criteria in 28 (13%). 96 (60%) of the pulmonary cases had cavitation. The most common therapeutic schedule (84%) was the recommended 9-month regimen. In 54% no recommendation for the investigation of contacts was made. CONCLUSIONS: In the authors' area, the prevalence of TB is higher than in developed countries. It is more common in middle aged individuals, many diagnoses are still made without bacteriologic studies and in a high number of cases investigation of contacts is not carried out.

Evaluation of the effect of nutrient ratios on biosurfactant production by Serratia marcescens using a Box-Behnken design.

The strain SmSA, identified as Serratia marcescens and known as a biosurfactant producer, was isolated from hydrocarbon contaminated soil from Veracruz, México. The interactions among the C/N, C/Mg and C/Fe ratios have not been examined for this microorganism. In this work was evaluated the effect of these nutrients at three levels using a mineral medium with glucose as the carbon source. A Box-Behnken experimental design was utilised to maximise biosurfactant production, which was assessed by oil spreading and surface tension tests. The treatment with C/N=5, C/Fe=26,000 and C/Mg=30 showed the best result since the surface tension was reduced to 30 mN m(-1). The multiple regression and response surface analyses indicated that the interaction between C/N and C/Mg had the utmost effect on the reduction of surface tension and biosurfactant production. The conditions of the best treatment were used to scale up biosurfactant production in a 3L bioreactor giving a yield of 4.1 gL(-1) of pure biosurfactant. It was found that the biosurfactant was mainly produced in the exponential phase and decreased the surface tension to 31 mN m(-1). The contact between the biosurfactant with heavy oil (15° API) increased its displacement from 9.3 to 18 cm.