Lolium perenne pollen from a polluted city shows high allergenic potency and increased associated enterobacteriaceae counts

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Hipocalcemia não puerperal em vacas leiteiras sob pastejo de aveia e azevém: estudo de fatores predisponentes / Non-parturient hypocalcaemia in lactating dairy cows grazing in oat and perennial ryegrass pasture: study of predisposing factors

A Hipocalcemia Não Puerperal (HNP) é uma condição rara e pouco compreendida. Não há estudos que expliquem a sua relação com a ingestão de pastagens de inverno como base da alimentação volumosa. Os objetivos deste trabalho foram descrever aspectos clínicos de dois casos naturais de HNP, e estudar o balanço mineral e eletrolítico de vacas leiteiras de alta e de média produção alimentadas em pastagem de inverno em diferentes estágios de evolução. Foram acompanhados dois casos de HNP em vacas leiteiras, mantidas em pastagens de aveia ou de azevém no município de Francisco Beltrão, PR. De três propriedades localizadas no mesmo município, foram selecionadas vacas lactantes hígidas de alta produção da raça Holandesa (n=11) e de média produção das raças Holandesa (n=8) e Jersey (n=9), mantidas em pastagem mista de aveia e azevém, de junho a outubro de 2011, e complementadas com silagem de milho. Amostras de sangue, de urina e dos alimentos ingeridos foram colhidas antes do ingresso na pastagem (maio), e nos estágios inicial (junho), intermediário (julho) e final (setembro) do ciclo de maturação da forragem. Foram determinadas as concentrações séricas e urinárias de Ca, P, Mg, Na+, K+, Cl- e creatinina e calculada as excreções fracionadas. Nas amostras de alimento foram determinadas a matéria seca (MS) e as concentrações de Ca, P, Mg, Na, K, Cl e S, e calculou-se a diferença entre cátions e ânions da dieta (DCAD) nos diferentes momentos. Com base nas evidências pode-se afirmar que vacas leiteiras em lactação mantidas em pastagem de aveia e/ou de azevém nos meses de inverno podem desenvolver hipocalcemia e exibir sinais clínicos e resposta ao tratamento similares aos da hipocalcemia puerperal clássica, mesmo não sendo recém paridas...

Non-parturient hypocalcaemia (NPH) is a rare and poor understood condition. There are no studies that explain its relationship with winter pasture intake. The aim of this study was to describe clinical aspects of two natural cases of NPH, and to study the mineral and electrolyte balance of high and medium producing dairy cows feeded with winter pasture in different growing stages. Two cases of NPH in lactating dairy cows, grazing in oat grass and perennial ryegrass in Francisco Beltrão, PR, Brazil, were described. Healthy lactating high producing Holstein cows (n=11) and medium producing Holstein (n=8) and Jersey (n=9) cows were selected from three farms located in the same municipality. They were maintained in a mixing pasture of oats and perennial ryegrass from June to October, and supplemented with corn silage. Blood, urine and ingested food samples were collected before treatment started (May), and during initial (June), intermediate (July) and final stages (September) of the grass maturation cycle. Serum and urinary concentrations of Ca, P, Mg, Na+, K+, Cl- and creatinine were determined, and their fractional excretion were calculated. Dry matter and Ca, P, Mg, Na, K, Cl and S concentrations were determined in food samples, and the dietary cation-anion difference was calculated. Based on clinical evidence we can assure that lactating dairy cows maintained in oat and perennial ryegrass pastures during the winter months can develop hypocalcaemia, showing signs and responding to treatment similar to classic puerperal hypocalcaemia, even in non-parturient period. Partial substitution of corn silage to oat and perennial ryegrass pasture did not cause electrolyte imbalances and did not interfere with the calcemia, phosphatemia or magnesemia of high and medium producing lactating dairy cows...

Increased presentations to emergency departments for asthma associated with rye grass pollen season in inland NSW.

AIM: This study measured the frequency and geographical extent of peaks in asthma presentations to emergency departments in inland NSW; it assessed the characteristics of patients who presented at peak presentation times during the rye grass pollination season (October-November) and at other times of the year. METHODS: Data describing over 13 years of daily emergency department presentations with a provisional diagnosis of asthma at nine inland NSW base hospitals were assembled. Days of counts in the top 0.1 percentile for each emergency department were classified as peak asthma count days. RESULTS: While the rye grass pollen season accounts for only 17% of days in the year, 53% of peak asthma count days fell within that period. Patients aged over 14 years represented 74% of visits on peak asthma count days during the pollen season and 50% on peak days at other times of the year. DISCUSSION: Under the right climatic conditions, rye grass pollen may be responsible for presentations for acute asthma to emergency departments in inland NSW.

Necrotic dermatitis in waterfowl associated with consumption of perennial rye grass (Lolium perenne).

Mute swans (Cygnus olor), whooper swans (Cygnus cygnus), and mixed-breed domestic geese (Anser anser domesticus) were presented for necrotic lesions on the feet, eyelids, and beak. Individuals from the same collection of birds had developed identical lesions during March-September of each of the previous 3 years. Vesicular and necrotic dermatitis involved only nonfeathered and nonpigmented areas of the integument. No abnormal clinical signs were seen on either carnivorous species or birds with pigmented skin from the same collection. The enclosure that housed the birds had been planted with perennial rye grass (Lolium perenne) 3 years previously. Based on the pathologic features and anatomic location of the lesions, the seasonal occurrence, the vegetation history of the enclosure, and the feeding behavior of the affected species, vesicular dermatitis resulting from photosensitization was the presumptive diagnosis. All affected birds recovered completely after the birds were removed from the enclosure, and no further clinical signs have been reported.

Surto de polioencefalomalacia por ingestão excessiva de enxofre na dieta em bezerros no Rio Grande do Sul / Outbreak of polioencephalomalacia in cattle consuming high sulphur diet in Rio Grande do Sul, Brazil

Neste trabalho descreve-se surto de polioencefalomalacia em bovinos decorrente da ingestão de dieta com excessiva concentração de enxofre em uma propriedade no Rio Grande do Sul. O lote era composto por 30 bezerros, mantidos em um piquete com azevém (Lolium multiflorum) e suplementados com ração e sal mineral. Seis bezerros morreram e dois deles foram necropsiados; amostras de tecido hepático para dosagem de chumbo e fragmentos do sistema nervoso central para histopatológico foram colhidos. Um dos bezerros foi examinado antes da morte e sinais neurológicos encefálicos foram constatados. Foi estabelecido o teor de enxofre nos componentes da dieta e água, a produção de sulfeto de hidrogênio ruminal em cinco bovinos do mesmo lote e realizada PCR de um bloco de parafina para detecção de DNA do herpevirus bovino tipo 5. O consumo total de enxofre foi de 0,38 por cento da matéria seca fornecida aos animais e as dosagens de sulfeto de hidrogênio ruminal em animais do mesmo lote variaram de 1.000 a 2.500ppm. Os achados histopatológicos indicaram necrose laminar do córtex cerebral. Não foi detectado chumbo na amostra de tecido hepático e não foi identificado DNA do herpesvirus bovino tipo 5 no encéfalo. O quadro clínico de síndrome cerebrocortical associado aos elevados valores do sulfeto de hidrogênio ruminal, alta ingestão de enxofre na dieta e os achados histopatológicos permitem estabelecer o excesso de enxofre como causador da polioencefalomalacia.

An outbreak of polioencephalomalacia in cattle caused by ingestion of high sulphur diet, in Rio Grande do Sul, Brazil is described. One group of 30 calves was kept in Italian ryegrass (Lolium multiflorum) pasture and supplemented with concentrate and minerals. Six calves died, necropsy was performed in two of them and liver samples (for lead determination) and fragments of central nervous system were collected. Clinical and neurological examination was performed in one calf and confirmed brain involvement. Sulphur content on dietary components and water, ruminal hydrogen sulfide production in five calves of the same group and PCR from formalin-fixed paraffin-embedded cerebral tissues to detect bovine herpesvirus 5 DNA was perfomed. The total sulphur intake was 0.38 percent dry matter and the values of ruminal sulfide concentration ranged from 1,000 to 2,500ppm. Lead It was not detected in the liver samples and PCR was negative for bovine herpesvirus 5. The brain lesions were characterized by laminar neuronal necrosis. The clinical signs of cerebrocortical syndrome associated with high ruminal sulfide values, elevated intake of dietary sulphur and histological lesions confirmed that the excess of sulphur caused the polioencephalomacia in these calves.

Pollen allergic disease: pollens and its major allergens.

Patients with grass pollen allergy, commonly called pollinosis, often present reactivity to pollen allergens from a number of grass species due to cross-reactivity of IgE antibodies to pollen proteins present in pollen grasses. In this context, Italian rye grass (Lolium multiflorum) pollen of the Poaceae family cultivated in Southern Brazil has been considered a major sensitizing agent in patients with pollinosis. In this region, Italian rye grass is capable of producing a great amount of pollen. In addition to L. multiflorum, other Poaceae grasses are naturally grown as weed in Southern Brazil, but with no clinical relevance. Pollen extracts derived from homologous or heterologous grasses are often used for both diagnosis and treatment of seasonal allergy. However, no standardized L. multiflorum pollen extract is commercially available in Brazil and mixed grass extracts are commonly used for diagnosis and immunotherapy of grass pollen allergy. Further studies are required to better characterize the cross-reactivity between L. multiflorum and other grass pollen allergens for improving the diagnosis and immunotherapy to L. multiflorum pollen allergy.

Doença alérgica polínica: polens alergógenos e seus principais alérgenos / Pollen allergic disease: pollens and its major allergens

Pacientes com alergia a pólen de gramíneas, comumente denominada polinose, freqüentemente apresentam reatividade a alérgenos de pólen de inúmeras gramíneas devido às reatividades cruzadas entre anticorpos IgE dirigidos contra proteínas presentes nos polens de gramíneas. Nesse contexto, pólen de Italian ryegrass (Lolium multiflorum), ou azevém anual, gramínea da família Poaceae cultivada no Sul do Brasil, é considerado o principal agente sensibilizante em pacientes com polinose. Nessa região, o azevém é capaz de produzir grande quantidade de pólen. Adicionalmente, outras gramíneas da família Poaceae crescem naturalmente no Sul, entretanto, sem relevância clínica. Extratos de pólen derivados de gramíneas homólogas ou heterólogas são freqüentemente empregados no diagnóstico e tratamento da alergia sazonal a pólen, sendo que para esses fins não se encontra comercialmente disponível no Brasil extrato padronizado de pólen de L. multiflorum. Futuros estudos serão importantes para melhor caracterizar a reatividade cruzada entre alérgenos de pólen de L. multiflorum e alérgenos de outras gramíneas com o objetivo de aprimorar o diagnóstico e imunoterapia de pacientes com alergia a pólen causada por L. multiflorum.

Patients with grass pollen allergy, commonly called pollinosis, often present reactivity to pollen allergens from a number of grass species due to cross-reactivity of IgE antibodies to pollen proteins present in pollen grasses. In this context, Italian rye grass (Lolium multiflorum) pollen of the Poaceae family cultivated in Southern Brazil has been considered a major sensitizing agent in patients with pollinosis. In this region, Italian rye grass is capable of producing a great amount of pollen. In addition to L. multiflorum, other Poaceae grasses are naturally grown as weed in Southern Brazil, but with no clinical relevance. Pollen extracts derived from homologous or heterologous grasses are often used for both diagnosis and treatment of seasonal allergy. However, no standardized L. multiflorum pollen extract is commercially available in Brazil and mixed grass extracts are commonly used for diagnosis and immunotherapy of grass pollen allergy. Further studies are required to better characterize the cross-reactivity between L. multiflorum and other grass pollen allergens for improving the diagnosis and immunotherapy to L. multiflorum pollen allergy.

Rye grass is associated with fewer non-contact anterior cruciate ligament injuries than bermuda grass.

OBJECTIVE: To assess the contribution of ground variables including grass type to the rate of anterior cruciate ligament (ACL) injury in the Australian Football League (AFL), specifically which factors are primarily responsible for previously observed warm season and early season biases for ACL injuries. METHODS: Grass types used at the major AFL venues from 1992 to 2004 were established by consultation with ground managers, and ground hardness and other weather variables were measured prospectively. RESULTS: There were 115 ACL injuries occurring in matches during the survey time period, 88 with a non-contact mechanism. In multivariate analysis, use of bermuda (couch) grass as opposed to rye grass, higher grade of match, and earlier stage of the season were independent risk factors for non-contact ACL injury. Ground hardness readings did not show a significant association with ACL injury risk, whereas weather variables of high evaporation and low prior rainfall showed univariate association with injury risk but could not be entered into a logistic regression equation. DISCUSSION: Rye grass appears to offer protection against ACL injury compared with bermuda (couch) grass fields. The likely mechanism is reduced "trapping" of football boots by less thatch. Grass species as a single consideration cannot fully explain the ACL early season bias, but is probably responsible for the warm season bias seen in the AFL. Weather variables previously identified as predictors are probably markers for predominance of bermuda over rye grass in mixed fields.

A prevalência de polinose está associada com a cultura de lolium multiflorum? / Is the prevalence of pollinosis associated to lolium multiflorum cultivation?

Objetivo: O objetivo do estudo foi estabelecer a prevalência de polinose (rinite estacional), em adultos em área com agricultura modificada pela introdução extensiva de Lolium multiflorum (Santo Ângelo) em um polo industrial (Caxias do Sul), localizados no estado do Rio Grande do Sul. Métodos: Utilizou-se o questionário escrito do International Study of Asthma and Allergies in Childhood modificado, previamente validado em Curitiba. A amostra for de 2.943 estudantes, 1.919 pertenciam à Universidade de Caxias do Sul e 1.024 à Universidade Regional Integrada, do Alto Uruguai e Missões, Campus de Santo Ângelo. A análise estatística para cálculo de prevalência foi limitada para residência (maior igual dois anos na região e maior igual quatro dias na cidade/semana). Resultados: Sintomas nasais e oculares nos últimos doze meses, com respostas afirmativas foram, em Caxias do Sul (43,0%) e Santo Ângelo (48,0%). Nos sintomas nasais em outubro e novembro (primavera) a frequencia afirmativa foi, respectivamente, em Caxias do Sul (35,1% e 15,3%) e Santo Ângelo (35,8% e 24,0%). Responderam "sim" sobre a alergia ao pólen na primavera, em Caxias do Sul (37,3%) e Santo Ângelo (46,8%). Conclusões: Os sintomas naso-oculares, associados à resposta afirmativa à alergia ao pólem na primavera, nos meses de outubro e novembro, permitem estabelecer uma prevalência de polinose (14,1%) em Caxias do Sul e (22,1%) para Santo Ângelo. A elevada prevalência de polinose encontrada em Santo Ângelo poderia estar relacionada com a cultura atual extensiva de Lolium multiflorum.

Characterization of the human T cell response to rye grass pollen allergens Lol p 1 and Lol p 5.

BACKGROUND: Knowledge of dominant T cell epitopes of major allergens recognized by allergic individuals is required to improve efficacy and safety of allergen immunotherapy. Rye grass pollen (RGP) is the most important source of seasonal aeroallergens in temperate climates and Lol p 1 and Lol p 5 are the two major IgE-reactive allergens. This study aimed to characterize the T cell response to these allergens using a large panel of RGP-sensitive individuals. METHODS: Short-term RGP-specific T cell lines (TCL) were generated from 38 RGP-sensitive subjects and stimulated with Lol p 1 and/or Lol p 5 allergens and synthetic 20-mer peptides. Proliferative responses were determined by 3H-thymidine uptake and IL-5 and IFN-gamma in culture supernatants analysed by ELISA. RESULTS: Of 17 subjects tested for reactivity to both allergens 16 (94%) responded to Lol p 1 and/or Lol p 5, establishing these as major T cell-reactive allergens. Sites of T cell reactivity were spread throughout the allergen molecules but regions of high reactivity were found. For Lol p 1 these spanned residues 19-38, 109-128, 154-173, 190-209, and for Lol p 5 37-56, 100-119, 145-164, 154-173, 190-209, 217-236 and 226-245. IL-5 and IFN-gamma were produced by T cells cultured with proliferation-inducing peptides. CONCLUSIONS: T cell responses to RGP major allergens have been extensively characterized, providing fundamental information for developing T cell-targeted immunotherapy for RGP allergy.

"Bystander" amplification of PBMC cytokine responses to seasonal allergen in polysensitized atopic children.

BACKGROUND: Atopic children show increased expression and production of the Th2-associated cytokines IL-4, IL-5, IL-13, and IL-9 from PBMCs after stimulation with allergen, but it has previously not been clearly determined whether the Th2-cytokine production is restricted to the inhalant allergen the child is sensitized to, and whether perennial or seasonal allergens induce different cytokine responses. Our purpose was to determine whether in vitro Th2 cytokine production is specific to the sensitizing allergen, and to compare the cytokine responses to a perennial and a seasonal allergen in monosensitized and polysensitized children. METHODS: Using semiquantitative RT-PCR, we analyzed the expression of the cytokines IL-4, IL-5, IL-13, IL-9, IL-10, and IFN-gamma after stimulation of PBMCs with house-dust-mite (HDM) or ryegrass allergen. The cells were sampled from groups of 6-year-old children sensitized to either HDM (n=20) or ryegrass (n=24), or to both allergens (n=20), as well as from a nonatopic group (n=20). RESULTS: After stimulation with HDM allergen, PBMCs from children sensitized only to HDM expressed increased mRNA levels of the Th2 cytokines, but not of IL-10 and IFN-gamma, whereas ryegrass stimulation did not result in increased cytokine expression. PBMCs from children sensitized to HDM and ryegrass expressed increased Th2 cytokines after stimulation with either of the two allergens. In contrast, PBMCs from children sensitized only to ryegrass did not express increased levels after stimulation with either of the allergens. CONCLUSIONS: The expression of Th2 cytokines after in vitro stimulation of PBMCs from atopic children is specific to the sensitizing allergen, indicating that atopic status per se does not affect the type of T-cell response. In addition, T cells specific to seasonal allergens circulate in the blood out of season only if the child is concomitantly sensitized to a perennial allergen.

Nedocromil sodium and levocabastine reduce the symptoms of conjunctival allergen challenge by different mechanisms.

BACKGROUND: Nedocromil sodium and levocabastine are widely used for the treatment of ocular allergy, but their mechanisms of action are unclear. OBJECTIVE: We sought to compare the efficacy and mechanisms of action of nedocromil sodium and levocabastine in reducing conjunctival symptoms after ocular allergen challenge. METHODS: We performed a double-blind, placebo-controlled study in which 48 subjects were randomized to 3 groups to receive nedocromil sodium (2%), levocabastine (0.05%), or placebo eye drops twice daily for 2 weeks before ocular challenge with 10 microL of ryegrass extract. Symptoms and tear histamine and PGD(2) concentrations were determined before challenge and at 10, 20, 30, 60, 180, and 360 minutes after challenge. Bulbar biopsy specimens were taken at 6 and 24 hours after challenge to assess conjunctival inflammatory cell numbers, adhesion molecule expression, and mast cell-associated IL-4, IL-5, IL-6, IL-13, and TNF-alpha levels. RESULTS: Both drugs significantly reduced total symptom scores (P <.05) at all times after challenge compared with placebo. Itching, hyperemia, and lacrimation were most affected. Nedocromil sodium treatment reduced tear concentrations of histamine (by 77%) and PGD(2) (by 70%) at 30 minutes after challenge (both P <.05). In biopsy specimens nedocromil sodium reduced the number of 3H4-positive mast cells (purportedly the secreted form of IL-4) by 49% at 6 hours and 59% at 24 hours (both P <.05). Levocabastine reduced intercellular adhesion molecule 1 expression by 52% at 6 hours and 45% at 24 hours (both P <.05). CONCLUSION: Nedocromil sodium and levocabastine both reduced the conjunctival symptoms after ocular allergen challenge but appeared to work by different mechanisms. Nedocromil sodium reduced mast cell function, whereas levocabastine appeared to have primarily antihistaminic actions, although it also reduced the expression of intercellular adhesion molecule 1.

Sensibilizaçäo atópica em escolares e adultos de Curitiba, Paraná / Atopic sensitization among schoolchildren and adults in Curitiba, Paraná

Objetivo: Determinar a freqüência de sensibilizaçäo atópica à Dermatophagoides pteronyssinus (DP) e Lolium multiflorum ( Lolium ) em escolares e adultos residentes em Curitiba, Paraná. Casuística e método: Foram avaliados 3271 escolares (13 e 14 anos), provenientes de 43 escolas de Curitiba e 3041 adultos (idade > 20anos) funcionários, médicos do Hospital de Clínicas e adultos da UFPR. Realizou-se teste cutâneo alérgico por puntura (TCA) com dois extratos alergênicos: DP 5000 AU/mL e Lolium 1:30 peso/volume (Bayer Corporation, USA). A leitura foi feita após 15 minutos e considerada reaçäo positiva aquela com pápula igual ou superior a 3 mm de diâmetro. Resultados: Observou-se uma freqüência de TCA positivo para DP em 31,3 por cento das crianças e 38,9 por cento dos adultos e para Lolium 4,7 por cento das crianças e 15,4 por cento dos adultos. A sensibilizaçäo exclusiva ao DP em crianças foi de 28,1 por cento, ao Lolium 1,5 por cento e a ambos 3,2 por cento. Em adultos, os valores foram de 26,8 por cento de sensibilidade exclusiva ao DP e 3,3 por cento ao Lolium e para ambos de 12,1 por cento. Conclusäo: Os resultados revelam a alta freqüência de sensibilizaçäo aos ácaros da poeira domiciliar na populaçäo geral e maior freqüência de reaçäo ao pólen de gramíneas em adulto do que em crianças.

Clinical efficacy and tolerance of two year Lolium perenne sublingual immunotherapy.

Last years, in spite of increasing use of sublingual immunotherapy (SLIT), not enough clinical studies have been published and its efficacy ought to be documented still more. For that purpose, 54 patients suffering seasonal rhinoconjunctivitis--with or without asthma--were allocated to either six month preseasonal SLIT with Lolium perenne extract (n = 35) or to a control group (n = 19). In the following year, thirty from previously treated patients and 12 from former control group, received a nine-month pre-coseasonal SLIT. Skin (SPT) and conjunctival (CPT) allergen response were monitorized several times along the study. Either seric antibodies or intraseasonal eosinophil cationic protein (ECP), as symptom, medication scores and peak nasal inspiratory flow (PNIF) were also assessed, fifty-five adverse reactions were recorded (0.7% doses), although only four required treatment. No main changes in CPT, SPT and antibodies were detected. Nevertheless, during the first pollen season, treated patients needed less medication than their control counterparts (p < 0.05). In the second season, the twelve ex-control subjects also required fewer drugs than in the first one (p < 0.01). Moreover, the whole forty-two treated patients showed a lesser intraseasonal ECP than a reference set of grass-allergic individuals (p < 0.05). We conclude that Lolium perenne SLIT is well tolerated and induces fewer drug requirements during pollen season, being eosinophil activation additionally reduced.