Biological activities and phytochemical screening of leaf extracts from Zanthoxylum caribaeum L. (Rutaceae) / Atividades biológicas e prospecção fitoquímica de extratos vegetais das folhas de Zanthoxylum caribaeum L. (Rutaceae)

The Brazilian flora is known for its vast biodiversity; however, many species have been still little studied regarding to their chemical composition and biological potential. Thus, this study aimed to determine the antimicrobial, antioxidant and acaricidal activity of the extracts of leaves of Zanthoxylum caribaeum L. In addition, phytochemical screening of these extracts was carried out to determine the main classes of secondary metabolites present in Z. caribaeum. Using the Z. caribaeum leaves, aqueous and organic extracts were obtained using the following solvents (ethanol, methanol, hexane, acetone, dichloromethane and ethyl acetate). The antimicrobial activity of extracts was determined by broth microdilution method, and to detect antioxidant activity the method of capturing the free radical 2,2-diphenyl-1-picryl hydrazyl (DPPH) was used. The acaricidal activity of the extracts was tested on Dermanyssus gallinae (De Geer) (Acari: Dermanissidae). Ethanolic and methanolic extracts presented antimicrobial activity for most of the bacterial strains tested, as well as for yeast Candida albicans. The ethanolic extract presented high free radical sequestration potential (71.2%) and antioxidant capacity (the lowest IC50 value - 24.39 µg mL-1). The crude extracts obtained with methanol and acetone were the most promising. In general, phytochemical screening indicated the presence of steroids, flavanones, flavones, flavonols, saponins, tannins, triterpenoids and xanthones.

A flora brasileira é conhecida pela sua vasta biodiversidade, no entanto, muitas espécies ainda são pouco estudadas quanto à composição química e ao potencial biológico. Assim, esse trabalho teve como objetivo determinar a atividade antimicrobiana, antioxidante e acaricida dos extratos vegetais das folhas de Zanthoxylum caribaeum L. Adicionalmente, foi realizada triagem fotoquímica desses extratos para determinar as principais classes de metabólitos secundários presentes em Z. caribaeum. Empregando-se as folhas de Z. caribaeum foram obtidos o extrato aquoso e orgânicos, utilizando os seguintes solventes (etanol, metanol, hexano, acetona, diclorometano e acetato de etila). A atividade antimicrobiana dos extratos foi determinada pelo método de microdiluição em caldo, e para detecção da atividade antioxidante foi empregado o método de captura do radical livre 2,2-difenil-1-picril hidrazil (DPPH). A atividade acaricida dos extratos foi avaliada frente a Dermanyssus gallinae (De Geer) (Acari: Dermanissidae). Os extratos brutos etanólico e metanólico apresentaram atividade antimicrobiana para a maioria das cepas bacterianas testadas, e também para a levedura Candida albicans. O extrato etanólico apresentou elevado potencial de sequestro de radicais livres (71,2%) e o menor valor de IC50 (24,39µg mL-1), revelando, portanto, sua capacidade antioxidante. No que se refere à atividade acaricida, os extratos obtidos com metanol e acetona foram os mais promissores. De modo geral, a triagem fitoquímica indicou a presença de esteroides, flavanonas, flavonas, flavonóis, saponinas, taninos, triterpenóides e xantonas.

Pathogenicity of Metarhizium anisopliae and Beauveria bassiana fungi to Tetranychus ludeni (Acari: Tetranychidae) / Patogenicidade de fungos Metarhizium anisopliae e Beauveria bassiana ao Tetranychus ludeni (Acari: Tetranychidae)

The use of acaricides is the main control method for Tetranychus ludeni (Acari: Tetranychidae) in horticultural crops. This mite has been recorded causing damage to sweet potato (Ipomoea batatas L.). The use of pathogenic fungi is an alternative to chemical control. The objective was to evaluate the pathogenicity of the fungi Metarhizium anisopliae (Meetch) Sorok, and Beauveria bassiana (Bals.) Vuill. to phytophagous mite T. ludeni in sweet potato plants. Conidial suspensions of M. anisopliae and B. bassiana, at concentrations of 106 and 107 con.mL-1 were applied to sweet potato leaves. After 24 hours, five females of T. ludeni newly emerged were released on the leaves. The bioassay was arranged in a completely randomized design with factorial arrangement 2 × 2 (two species of fungi and two concentrations) plus the control (distilled water), with 10 repetitions per treatment. The evaluation consisted of observing of three biological parameters of the mite: mortality, oviposition, and repellency, after 24, 48, 72, and 96 hours of contact with the fungi. The isolates of M. anisopliae cause high mortality rates of T. ludeni in laboratory. Beauveria bassiana has the potential to suppress future generations of mite, reducing its oviposition rate. Repellency behavior was not observed.(AU)

O uso de acaricidas é o principal método de controle de Tetranychus ludeni (Acari: Tetranychidae) em cultivos hortícolas. Esse ácaro foi registrado causando danos em batata-doce (Ipomoea batatas (L.). A utilização de fungos patogênicos é uma alternativa ao controle químico. O objetivo foi avaliar a patogenicidade dos fungos Metarhizium anisopliae (Meetch) Sorok. e Beauveria bassiana (Bals.) Vuill. ao ácaro fitófago T. ludeni em batata-doce. Suspensões conidiais de M. anisopliae e B. bassiana, nas concentrações de 106 e 107 con.mL-1, foram aplicadas sobre folhas de batata-doce. Após 24 horas, cinco fêmeas recém-emergidas foram liberadas sobre as folhas. O bioensaio foi inteiramente randomizado, com arranjo fatorial 2 × 2 (duas espécies de fungos e duas concentrações) e controle (água destilada), com 10 replicações por tratamento. A avaliação consistiu na observação de três parâmetros biológicos do ácaro: mortalidade, oviposição e repelência, após 24, 48, 72 e 96 horas de contato com os fungos. Os isolados de M. anisopliae causam altas taxas de mortalidade de T. ludeni em laboratório. Beauveria bassiana tem potencial para suprimir futuras gerações do ácaro, reduzindo a taxa de oviposição. Comportamento de repelência nos ácaros não foi observado.(AU)

Lethal and sublethal effects of pesticides used in Brazilian citrus groves on Panonychus citri (Acari: Tetranychidae) / Efeitos letais e subletais de agrotóxicos utilizados em citros sobre o ácaro Panonychus citri (Acari: Tetranychidae)

Pesticides have been blamed as the principal factor responsible for biological disequilibrium favoring the population increase of Panonychus citri (McGregor) in Brazilian citrus groves. In order to generate subsidies for the integrated management of this pest, we evaluated the lethal and sublethal effects of pesticides used in citrus on P. citri. We tested 18 pesticides by evaluating mortality of adult female, egg viability and adult avoidance. For imidacloprid, pyriproxyfen, dimethoate, deltamethrin, lambda-cyhalothrin and lime sulfur, the principal insecticides used in Brazilian orchards, the oviposition behavior and the incidence of adult females on discontinuous pesticide residues were evaluated. The pesticides which caused adult P. citri mortality were: abamectin (94%), dimethoate (86%), lime sulfur (69%), fenpropathrin (44%), diafenthiuron (25%) and lambda-cyhalothrin (23%). The pesticides affecting egg viability were: fenpropathrin (53%), dimethoate (30%) and lime sulfur (22%). Fenpropathrin, lambda-cyhalothrin and lime sulfur caused repellent effects of 55, 45 and 22%, respectively. P. citri preferred areas untreated with deltamethrin, lambda-cyhalothrin and lime sulfur for oviposition and permanence, but the species could not distinguish areas treated with imidacloprid, pyriproxyfen and dimethoate. The insecticides abamectin, dimethoate and diafenthiuron affected survival and did not cause changes in P. citri behavior. These pesticides should be used mainly in periods P. citri occurs. On the other hand, fenpropathrin, lambda-cyhalothrin, lime sulfur and deltamethrin affect dispersal behavior, oviposition and P. citri incidence and their use should be avoided.(AU)

O intenso uso de pesticidas na citricultura tem sido apontado como o principal fator responsável por desequilíbrios biológicos, favorecendo o aumento populacional de Panonychus citri (McGregor) na citricultura brasileira. Para gerar subsídios ao manejo integrado dessa praga, avaliaram-se os efeitos letais e subletais de agrotóxicos utilizados em citros sobre P. citri. Avaliaram-se 18 agrotóxicos na mortalidade de fêmeas adultas, viabilidade de ovos e repelência de P. citri. Foram também avaliados o comportamento de oviposição e a incidência de P. citri em superfícies com áreas tratadas e não tratadas com imidacloprid, piriproxifem, dimetoato, deltametrina, lambda-cialotrina e calda sulfocálcica, por serem os principais inseticidas utilizados nos pomares brasileiros. Os pesticidas que causaram mortalidade em adultos de P. citri foram abamectina (94%), dimetoato (86%), calda sulfocálcica (69%), fempropatrina (44%), diafentiurom (25%) e lambda-cialotrina (23%). Os pesticidas que afetaram a viabilidade de ovos foram fempropatrina (53%), dimetoato (30%) e calda sulfocálcica (22%). Quanto aos efeitos subletais, fempropatrina, lambda-cialotrina e calda sulfocálcica ocasionaram repelências de 55, 45 e 22%, respectivamente. P. citri preferiu áreas não tratadas com deltametrina, lambda-cialotrina e calda sulfocálcica para oviposição e permanência. Em contraste, P. citri não foi capaz de distinguir superfícies tratadas com imidacloprid, piriproxifem e dimetoato. Os inseticidas abamectina, dimetoato e diafentiurom afetaram a sobrevivência e não causaram mudanças no comportamento de P. citri, podendo ser utilizados principalmente em períodos que P. citri ocorre. Em contrapartida, fempropatrina, lambda-cialotrina, calda sulfocálcica e deltametrina afetaram o comportamento de dispersão e oviposição de P. citri e deveriam ser evitados.(AU)

Aspectos biológicos de Tetranychus ludeni Zacher, 1913 (Acari: Tetranychidae) alimentados com folhas de batata-doce pulverizadas com o 2,4-D / Biological aspects of Tetranychus ludeni Zacher, 1913 (Acari: Tetranychidae) fed on sweet potato leaves sprayed with 2,4-D

Batata-doce [Ipomoea batatas (L.) Lam.] apresenta grande versatilidade de usos no Brasil. Com a ampliação das áreas de cultivo, essa espécie estará sujeita à contaminação por herbicidas. Eventualmente, organismos não alvos podem ser expostos aos resíduos. O objetivo deste trabalho foi avaliar aspectos biológicos do ácaro Tetranychus ludeni alimentado com folhas de batata-doce pulverizadas com diferentes doses do herbicida 2,4-D. O experimento foi conduzido no Laboratório de Controle Biológico da Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), em Diamantina, Minas Gerais. Foram utilizadas 175 fêmeas de T. ludeni e 6 doses de 2,4-D, em g.ha-1 (8,06; 20,15; 40,30; 80,60; 201,50; e 806,00), mais o tratamento-controle com água destilada. Adotou-se delineamento inteiramente casualizado, com sete tratamentos e cinco repetições, contendo cinco fêmeas de T. ludeni em cada repetição. Foram avaliados a mortalidade inicial do ácaro em 24 h, o número de ovos, as ninfas e a longevidade das fêmeas. Os dados foram submetidos à análise de variância, sendo as médias significativas analisadas pelo teste de Duncan. Observou-se que doses maiores desse herbicida podem aumentar a mortalidade e reduzir a longevidade das fêmeas de T. ludeni.(AU)

Sweet potato [Ipomoea batatas (L.) Lam.] presents great versatility of uses in Brazil. With the expansion of crop areas, this species is subject to contamination by herbicides. Eventually, non-target organisms can be exposed to residues . The aim of this study was to evaluate biological aspects of the mite Tetranychus ludeni fed on sweet potato leaves sprayed with different doses of the herbicide 2,4-D. The experiment was conducted at the Biological Control Laboratory of Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Minas Gerais, Brazil. Altogether, 175 females of T. ludeni and six doses of 2,4-D, in g.ha-1 (8.06, 20.15, 40.30, 80.60, 201.50, and 806,00) were used, plus the control done with distilled water. It was adopted a completely randomized design with seven treatments and five replications with five females each. Early mortality of T. ludeni (24 h), the number of eggs, nymphs and longevity of females were evaluated. Data were subjected to analysis of variance, being the significant mean analyzed by Duncan test. It was observed that high doses of the herbicide may increase the mortality and decrease longevity of females of T. ludeni.(AU)

Toxicidade e repelência de extratos de plantas da caatinga sobre Tetranychus bastosi Tutler, Baker & Sales (Acari: Tetranychidae) em pinhão-manso / Toxicity and repellency of caatinga plant extracts on the Tetranychus bastosi Tutler, Baker & Sales in physic nut

RESUMO O objetivo deste trabalho foi avaliar o efeito repelente e a toxicidade dos extratos aquosos de Myracrodruon urundeuva Fr. All (Anacardiaceae), Croton blanchetianus Baill (Euphorbiaceae) e Ziziphus joazeiro Mart. (Rhamnaceae,) sobre o ácaro Tetranychusbastosi Tutler, Baker & Sales associado à cultura do pinhão- manso Jatropha curcas L. Para cada extrato as concentrações utilizadas foram 0, 5%, 10%, 15%, 20% e 25%. Avaliou-se, em teste sem chance de escolha, a mortalidade de fêmeas adultas de T. bastosi submetidas às diferentes concentrações de cada extrato. O delineamento estatístico foi o inteiramente casualizado, com seis tratamentos (testemunha e concentrações dos extratos) e 10 repetições. Os dados foram submetidos à análise de regressão. Também foi avaliado o efeito repelente dos referidos extratos sobre T. bastosi, nas concentrações supracitadas. Foi calculado o índice de repelência, percentual de repelência, classificação e índice de segurança. Os dados de percentual de repelência de adultos no tratamento e testemunha foram analisados pelo teste T de Student a 5% de probabilidade. De uma forma geral os extratos demonstraram efeito tóxico para adultos de T. bastosi nas concentrações testadas. O extrato de Z. joazeiro apresentou as maiores taxas de mortalidade (90%) média dos indivíduos. No que se refere à repelência destes extratos, todos os tratamentos se mostraram repelentes para fêmeas de T. bastosi, classificados como tratamentos repelentes, exceto para a dosagem de 5% do extrato de M. unrundeuva.

ABSTRACT The aim of this study was to evaluate the repellent effect and toxicity of aqueous extracts of M. urundeuva All Br. (Anacardiaceae), Crotonblanchetianus Baill( Euphorbiaceae ) and Ziziphus joazeiro Mart. (Rhamnaceae) on the mite Tetranychus bastosi Tutler, Baker & Sales associated with Jatropha curcas. For each extract, the concentrations used were 0, 5%, 10 %, 15 %, 20% and 25%. It was evaluated, at a no-choice test, the mortality of adult females of T. bastosi submitted to different concentrations of each extract. The experimental design was completely randomized with six treatments (control and concentrations of the extracts) and 10 repetitions. The data were subjected to regression analysis. The repellent effect of the extracts over the T. bastosi, in the concentrations already mentioned was also evaluated. The repellency index, percentage repellency, classification and safety index were assessed. The data of percentage repellency of adults in treatment and control were analyzed by the T test Student a 5% probability. In general, the extracts showed toxic effect on adults of T. bastosi for the concentrations tested. The extract of Z. joazeiro indicated d the highest average mortality rates (90 %) of individuals. Regarding the repellency of these extracts, all treatments have proved to be repellants for the females of T. bastosiclassified as repellent treatment, except for the 5% dose of the extract of M. unrundeuva.

Comparação da eficiência de diferentes armadilhas utilizadas para a captura de Dermanyssus gallinae (Acari: Dermanyssidae) (de Geer, 1778) / Comparison of different sampling traps for Dermanyssus gallinae (Acari: Dermanyssidae) (de Geer, 1778)

O presente trabalho teve como objetivo comparar a eficiência de armadilhas de papel corrugado com a de armadilhas de colmo de bambu taquaril (Phyllostachys sp.) seco na captura de Dermanyssus gallinae, presentes em uma bateria de gaiolas de metal utilizadas na criação de galinhas de postura. A presença de ovos no interior de cada tipo de armadilha foi comparada por meio do teste de Qui-Quadrado e pelo intervalo de confiança para duas proporções. Os valores das somas de estágios móveis nas diferentes armadilhas a cada intervalo de tempo foram comparados utilizando-se o teste de Wilcoxon. A proporção de armadilhas contendo ovos não foi diferente nos dois tipos de armadilha (p < 0,05). O número total de estágios móveis capturados durante a coleta a cada dois dias de intervalo em cada tipo de armadilha foi diferente (p < 0,01), enquanto que as contagens, nas armadilhas de papelão, apresentaram distribuição normal e foram superiores aos valores de espécimes móveis capturados nas armadilhas de bambu.

This work aims to compare the performance of corrugated paper and "taquaril" bamboo (Phyllostachys sp.) straw traps for collecting (in sampling) Dermanyssus gallinae in a metal cages battery laying hens. The presence of eggs in the two trap models were compared using a Qui-square test and a proportion confidence interval test. Total daily values of mobile instars gathered in each type of trap were compared using the Wilcoxon's test. The amount of traps containing eggs was not different in neither of the traps (p < 0,05). The number of mobile instars sampled at every two days per trap model was different (p < 0,01). Counting in the corrugated paper traps showed a Gauss distribution histogram and was superior to the values of the bamboo straw traps.

Plano de amostragem presença-ausência para Oligonychus yothersi (McGregor) (Acari: Tetranychidae) na cultura da erva-mate / Presence-absence sampling plan for Oligonychus yothersi (McGregor) (Acari: Tetranychidae) on mate-tea orchard

O ataque de ácaros na cultura da erva-mate tem freqüentemente provocado perdas pela queda precoce das folhas. Assim, há necessidade de se monitorar a população desses artrópodes e adotar estratégias de manejo. O objetivo deste trabalho foi avaliar a confiabilidade da amostragem presença-ausência para Oligonychus yothersi (McGregor) na erva-mate. O trabalho foi realizado em um erval comercial, em Cascavel, PR, de abril de 1999 a julho de 2000. Coletas quinzenais de 240 folhas foram feitas em diferentes partes de 10 plantas escolhidas ao acaso. A contagem dos ácaros nas folhas foi realizada em laboratório com auxílio de microscópio estereoscópico. Foi determinado o padrão de agregação através dos coeficientes a e b da lei da potência de Taylor; a proporção de folhas infestadas e o número de amostras requeridas foram estimados através de modelo matemático. O. yothersi apresentou distribuição agregada. A proporção de folhas infestadas calculada pelo modelo matemático mostrou ser um parâmetro confiável para estimar a densidade populacional do ácaro. O número de amostras requeridas foi pequeno, viabilizando a aplicação prática do método de amostragem presença-ausência para O. yothersi na cultura da erva-mate.

Mite infestations to the culture of mate-tea frequently causes losses by the premature fall of the leaves. So, it is necessary to monitor the population of these arthropods, and to adopt management strategies for their control. The objective of this research was to evaluate the trustworthiness of presence-absence sampling for Oligonychus yothersi (McGregor) on mate-tea orchard. This study was conducted in Cascavel, Paraná State, from April 2001 to July 2000, in a mate-tea tree commercial plantation. Biweekly sampling of 240 leaves were collected in different parts of 10 plants, and the number of mites was counted. The aggregation pattern was determined through the coefficients a and b of Taylor's power law. The proportion of infested leaves and the number of required samples were estimated through mathematical model. The mite O. yothersi presented aggregate distribution. The proportion of infested leaves calculated by means of mathematical model showed to be a trustworthy parameter to estimate the population density of the mite. The number of required samples was small, making feasible the practical application of the presence-absence sampling method for O. yothersi in the culture of mate-tea.

Seleção de fungos entomopatogênicos para o controle de Oligonychus yothersi (McGregor) (Acari: Tetranychidae), na cultura da erva-mate (Ilex paraguariensis St. Hill.) / Entomopathogenic fungi selection to control Oligonychus yothersi (McGregor) (Acari: Tetranychidae) in Paraguay tea crops (Ilex paraguariensis St. Hill.)

The virulence of strains of the entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliae and Paecilomyces fumosoroseus was evaluated on Oligonychus yothersi (McGregor) in laboratory. The bioassays for strain selection and determination of LD50 and LT50 were elaborated withleaf disks of Paraguay tea infested with 10 adult females of the mite. Groups of five disks were sprayed with 1 ml of the suspension standardized in 1.0x107 conidia per ml (50 mites per treatment) of each strain. After that, the disks were maintained floating in distilled water in plastic boxes (3 cm diameter and 1.5 cmheight), in environmental chamber (temperature: 25 ± 1ºC; RH: 71 ± 10% and 12h photophase). Five days after the inoculation the total mortality was evaluated, and the dead mites were transferred to humid chamber. Six days after death, the sporulation in the cadavers was examined under an optical microscope. B. bassiana presented great potential as a microbial control agent, and can be incorporated in integratedpest management of the Paraguay tea red mite, O. yothersi. The B. bassiana strains UEL02, UEL08, UEL10, UEL50, CG082, CG166, CG375, CG424 and CG481, were the most virulent, with corrected and confirmed mortality higher than 70% and estimated value of CL50 varying between 1.9x106 and 6.0x107 conidia per ml and TL50 varying between 3.3 and 4.3 days.

A virulência de isolados dos fungos entomopatogênicos Beauveria bassiana, Metarhizium anisopliae e Paecilomyces fumosoroseus foi avaliada sobre Oligonychus yothersi (McGregor) emlaboratório. Os bioensaios de seleção e de determinação de CL50 e TL50 foram realizados com discos foliares de erva-mate previamente infestados com 10 fêmeas adultas do ácaro. Para cada isolado um conjunto de cinco discos foram pulverizado com 1 ml da suspensão padronizada em 1,0x107 conídios/ml (50 ácaros por tratamento). Após pulverizados os discos foram mantidos flutuando em água destiladaem caixas plásticas (3 cm diâmetro e 1,5 cm altura), em câmara tipo B.O.D. (temperatura: 25 ± 1oC; UR: 70± 10% e fotofase de 12h). A mortalidade total foi avaliada cinco dias após a inoculação. Os ácaros mortos foram transferidos para câmara úmida para confirmação de mortalidade, sendo examinados sob microscópio ocular seis dias após a morte. O fungo B. bassiana apresentou grande potencial comoagente de controle microbiano, podendo ser incorporado em programas de manejo integrado do ácaro vermelho da erva-mate, O. yothersi. Os isolados de B. bassiana UEL02, UEL08, UEL10, UEL50, CG082, CG166, CG375, CG424 e CG481 foram os mais virulentos. Eles apresentaram mortalidades corrigida econfirmada superiores a 70% e valores estimados de CL50 variando entre 1,9x106 e 6,0x107 conídios/ml e de TL50 variando entre 3,3 e 4,3 dias.

Prevalence of asthma and atopy in children living in rural areas of Cheju island for an interval of three years / 천식및알레르기

BACKGROUND: The prevalence of asthma has been increasing due to changes in lifestyles. OBJECTIVE: The aim of this study was to evaluate the prevalence of asthma and atopy for an interval of three years in children living in rural areas of Cheju island. METHODS: A total of 1,055 and 755 subjects aged 7-15 years in South Cheju County were enrolled for an interval of three years, respectively. They responded to the modified ISAAC questionnaire, and underwent allergy skin prick test with locally common aeroallergens and methacholine bronchial provocation test. Children who had asthma symptom as reported on the questionnaire and bronchial hyperresponsiveness to methacholine were diagnosed as current asthma. Atopy was defined as the positive skin responses to one or more aeroallergens. RESULTS: The prevalence of current asthma had increased from 4.4% to 7.0% during the three years, especially among children aged 13 to 15 years (3.9% vs. 7.6%), although the asthma prevalence was similar between the two intervals among children aged 7 to 12 years (5.2% vs. 6.8%). The atopy rate had significantly increased from 37.7% to 45.9% during the three years. As for common sensitizing aeroallergens, sensitization rate to citrus red mite had significantly increased among both the young and the old age groups. The sensitization rates to house dust mites, such as D. pteronyssinus and D. farinae, had increased among the old age groups, but not among the young age groups, although the sensitization rates to cockroach and Japanese cedar pollen were similar among both the young and old age groups at the two intervals. CONCLUSION: The prevalence of current asthma and atopy had increased among children living in rural areas of Cheju island during the three year interval. The sensitization to house dust mite and citrus red mite had increased during the three years, and may play an important role in the increased prevalence of current asthma.

Distinct effect of sensitization of house dust mite and citrus red mite (Panonychus citri) in the development of allergic diseases in 16-18 year old adolescents living in rural areas of Jeju island / 천식및알레르기

BACKGROUND: A recent investigation has demonstrated that citrus red mite (Panonychus citri) is the most important allergen in citrus-cultivating farmers with asthma or rhinitis. METHODS: A total of 2,005 adolescents (aged 16 to 18 years) living in rural areas were enrolled in this study. Each subject was evaluated by a questionnaire developed by the International Study of Allergy and Asthma in Childhood(ISSAC), and a skin prick test with 11 common inhalant allergens including citrus red mite. RESULTS: Prevalence of recent wheezing, recent rhinoconjunctivitis symptoms and eczema was 13.0%, 13.6% and 9.9%, respectively. On skin prick test, the most common sensitizing allergen was citrus red mite (20.6%), followed by Dermatophagoides pteronyssinus (18.5%), Dermato-phagoides farinae (14.6%) and cockroach (9.8). The prevalence of eczema was higher in those with sensitization to CRM than in those without sensitization to any allergens(p 0.05). On the contrary, the sensitization to house dust mites were significantly associated with the prevalence of asthma and allergic rhinitis. CONCLUSION: Citrus red mite was the most common sensitizing allergen in 16-18 year-old adolescents living in rural areas with citrus farms and sensitization to CRM was significantly associated with the prevalence of atopic dermatitis.

A Prospective Study of Asthma Prevalence and Atopy Rate in Children Living in Rural Area of Cheju Island for 3 Years / 소아알레르기및호흡기학회지

PURPOSE: Asthma has been increasing due to changes in life style and indoor environments. Manifestations of asthma and atopy varies according to age. The purpose of this study was to elucidate the changing prevalence of asthma and atopy in children living in rural area of Cheju island via three year prospective study. METHODS: A total of 314 subjects aged from 7 to 12 years was followed up for three years. They responded a ISAAC questionnare, underwent allergy skin prick test with common aeroallergens and methacholine bronchial provocation test. Children with asthma symptoms on a questionnaire and positive methacholine bronchial provocation test were diagnosed as bronchial asthma. Skin prick test was regarded as positive when the size of wheal caused by allergens was same or larger than that caused by histamine. RESULTS: The prevalence of bronchial asthma has a tendency to increase from 4.1 % to 7.3% three years later(P=0.08). The atopy rate has significantly increased from 34.1% to 49.2% in both girls and boys(P<0.001), from 35.0% to 46.9% in girls(P< 0.05), and from 33.3% to 51.3% in boys(P<0.05). The positive skin responses to Dermatophagoides pteronyssinus, D. farinae(P=0.36), Japanese cedar and cockroach were not changed between the three years. However, the postive skin reponse to citrus red mite was significantly increased three years later(from 10.7% to 31.1%, P<0.001). CONCLUSION: The asthma prevalence has a tendency to increase in children living in rural area with citrus farms. The atopy rate has been also increasing in the rural children. These phenomena may be explained by the fact that sensitization to citrus red mite has been increasing when they are getting older.

Association between HLA-DRB1 alleles and the sensitization to citrus red mite (Panonychus citri) / 천식및알레르기

BACKGROUND: Recent investigations have demonstrated that citrus red mite (Panonychus citri, CRM) is an important allergen in the development of asthma in the rural population. The aim of this study was to investigate whether susceptibility or resistance to IgE responses to CRM was associated with HLA-DRB1 alleles. MATERIAL AND METHODS: Blood samples were obtained from two groups of unrelated Korean adolescents: 298 CRM-sensitive subjects and 99 age-matched non-atopic healthy controls. Sensitization to CRM was evaluated using skin-prick responses and serum specific IgE levels. Genotyping of HLA-DRB1 alleles was carried out using PCR-based methods. RESULTS: The frequency of DRB1*07 was significantly higher in the IgE responders to CRM (15.1%) than in the controls (3.0%), but the frequency of the other alleles was the same between the two groups. CONCLUSIONS: HLA-DRB1*07 was significantly associated with sensitization to CRM, and may be a risk factor for the sensitization to this allergen.

Risk factors for the sensitization to citrus red mite (Panonychus citri) in adolescents living in rural areas of Cheju island / 천식및알레르기

INTRODUCTION: Recent investigations have demonstrated that citrus red mite is a common sensitizing allergen in children and adults living in rural areas of Cheju island. OBJECTIVE: The aims of this study were to evaluate the sensitization rate to the citrus red mite and to determine the risk factors for this sensitization in adolescents living in rural areas of Cheju island. SUBJECTS AND METHODS: A total of 3,395 adolescents (from ages 13 to 15 years old) living in rural areas of Cheju island were enrolled in this study. Each subject was evaluated by a modified ISAAC questionnaire, and a skin prick test with 11 common inhalant allergens including citrus red mite. RESULTS: On skin prick test the most common sensitizing allergen was D. pteronyssinus (27.9%), followed by D. farinae (23.9%), citrus red mite (18.3%), and cockroach (16.7%). Sensitization rate to citrus red mite was higher in those living near citrus orchards than in those living far from the orchards, and higher in those visiting citrus orchards more frequently than in those visiting less frequently. CONCLUSION: Citrus red mite is a common sensitizing allergen in adolescents living in rural areas of Cheju island. The sensitization rate to citrus red mite may be partially determined by environ- mental exposure.

Specific IgG1 and IgG4 antibodies to citrus red mite in citrus farmers: a study of their relationship to respiratory symptoms

Citrus red mite (CRM) is known as the most common sensitizing allergen in subjects with asthma and rhinitis working on citrus farms. The aim of this study is to evaluate the role of specific IgG1 (slgG1) and specific IgG4 (slgG4) to CRM in citrus farmers. Questionnaire survey and skin prick test including CRM antigen was done by 136 workers. Specific IgE (slgE), slgG1 and slgG4 to CRM were detected by enzyme-linked immunosorbent assay (ELISA). CRM-sensitive-asthma was diagnosed upon presence of asthmatic symptoms by questionnaire, airway hyperresponsiveness to methacholine and slgE to CRM. CRM-sensitive rhinitis was diagnosed upon presence of rhinitis symptoms and slgE to CRM. Eleven (8.1+ACU-) had CRM-sensitive asthma and 25 (18.4+ACU-) had CRM-sensitive rhinitis. Significant association was noted between presence of asthmatic symptoms and slgE or slgG4 (p+ADw-0.05, respectively), while no significant association was noted in slgG1 (p+AD4-0.05). Significant association was noted in the prevalence between slgG4 and slgE (p+ADw-0.05), while no significant association was noted between slgG1 and slgG4 or slgE (p+ADw-0.05, respectively). There was a significant correlation between slgE and slgG4 level (r+AD0-0.39, p+ADw-0.05). These findings suggest that the presence of slgG1 to CRM is response to CRM exposure, and further studies will be needed to evaluate the role of slgG4.Citrus red mite (CRM) is known as the most common sensitizing allergen in subjects with asthma and rhinitis working on citrus farms. The aim of this study is to evaluate the role of specific IgG1 (slgG1) and specific IgG4 (slgG4) to CRM in citrus farmers. Questionnaire survey and skin prick test including CRM antigen was done by 136 workers. Specific IgE (slgE), slgG1 and slgG4 to CRM were detected by enzyme-linked immunosorbent assay (ELISA). CRM-sensitive-asthma was diagnosed upon presence of asthmatic symptoms by questionnaire, airway hyperresponsiveness to methacholine and slgE to CRM. CRM-sensitive rhinitis was diagnosed upon presence of rhinitis symptoms and slgE to CRM. Eleven (8.1+ACU-) had CRM-sensitive asthma and 25 (18.4+ACU-) had CRM-sensitive rhinitis. Significant association was noted between presence of asthmatic symptoms and slgE or slgG4 (p+ADw-0.05, respectively), while no significant association was noted in slgG1 (p+AD4-0.05). Significant association was noted in the prevalence between slgG4 and slgE (p+ADw-0.05), while no significant association was noted between slgG1 and slgG4 or slgE (p+ADw-0.05, respectively). There was a significant correlation between slgE and slgG4 level (r+AD0-0.39, p+ADw-0.05). These findings suggest that the presence of slgG1 to CRM is response to CRM exposure, and further studies will be needed to evaluate the role of slgG4.

Specific IgG1 and IgG4 antibodies to citrus red mite in citrus farmers: a study of their relationship to respiratory symptoms

Citrus red mite (CRM) is known as the most common sensitizing allergen in subjects with asthma and rhinitis working on citrus farms. The aim of this study is to evaluate the role of specific IgG1 (slgG1) and specific IgG4 (slgG4) to CRM in citrus farmers. Questionnaire survey and skin prick test including CRM antigen was done by 136 workers. Specific IgE (slgE), slgG1 and slgG4 to CRM were detected by enzyme-linked immunosorbent assay (ELISA). CRM-sensitive-asthma was diagnosed upon presence of asthmatic symptoms by questionnaire, airway hyperresponsiveness to methacholine and slgE to CRM. CRM-sensitive rhinitis was diagnosed upon presence of rhinitis symptoms and slgE to CRM. Eleven (8.1+ACU-) had CRM-sensitive asthma and 25 (18.4+ACU-) had CRM-sensitive rhinitis. Significant association was noted between presence of asthmatic symptoms and slgE or slgG4 (p+ADw-0.05, respectively), while no significant association was noted in slgG1 (p+AD4-0.05). Significant association was noted in the prevalence between slgG4 and slgE (p+ADw-0.05), while no significant association was noted between slgG1 and slgG4 or slgE (p+ADw-0.05, respectively). There was a significant correlation between slgE and slgG4 level (r+AD0-0.39, p+ADw-0.05). These findings suggest that the presence of slgG1 to CRM is response to CRM exposure, and further studies will be needed to evaluate the role of slgG4.Citrus red mite (CRM) is known as the most common sensitizing allergen in subjects with asthma and rhinitis working on citrus farms. The aim of this study is to evaluate the role of specific IgG1 (slgG1) and specific IgG4 (slgG4) to CRM in citrus farmers. Questionnaire survey and skin prick test including CRM antigen was done by 136 workers. Specific IgE (slgE), slgG1 and slgG4 to CRM were detected by enzyme-linked immunosorbent assay (ELISA). CRM-sensitive-asthma was diagnosed upon presence of asthmatic symptoms by questionnaire, airway hyperresponsiveness to methacholine and slgE to CRM. CRM-sensitive rhinitis was diagnosed upon presence of rhinitis symptoms and slgE to CRM. Eleven (8.1+ACU-) had CRM-sensitive asthma and 25 (18.4+ACU-) had CRM-sensitive rhinitis. Significant association was noted between presence of asthmatic symptoms and slgE or slgG4 (p+ADw-0.05, respectively), while no significant association was noted in slgG1 (p+AD4-0.05). Significant association was noted in the prevalence between slgG4 and slgE (p+ADw-0.05), while no significant association was noted between slgG1 and slgG4 or slgE (p+ADw-0.05, respectively). There was a significant correlation between slgE and slgG4 level (r+AD0-0.39, p+ADw-0.05). These findings suggest that the presence of slgG1 to CRM is response to CRM exposure, and further studies will be needed to evaluate the role of slgG4.

Antigenic distribution of HLA - DRB1 locus in citrus red mite ( Panonychus citri ) - sensitive asthma / 천식및알레르기

BACKGROUND: Specific IgE responses to allergens provide useful models for evaluating the genetic factors that control human immune responses. HLA class II gene products are involved in the antigen presentation of exogenous antigens. OBJECTIVE: The aim of this study was to evaluate whether susceptibility or resistance to asthma induced by the citrus red mite (Panonychus citri, CRM) was associated with HLA class II gene-encoded antigens. METHODS: Peripheral venous blood samples were collected from two groups of unrelated Korean adults. Ninety-one patients with citrus red mite-induced asthma and 98 exposed, healthy control subjects. The second exon of the HLA-DRB1 genes was selectively amplified by the polymerase chain reaction method. HLA typing was carried out using PCR-sequence specific oligonucleotide probes(PCR-SSOP). RESULTS: The frequency of HLA-DR7 was significantly higher among the CRM-sensitive asthmatics than among the controls (17.6% vs 4.1%, RR=3.92, p=0.01). Conversely, the frequency of HLA-DR4 was significantly lower among the CRM-sensitive asthmatics than among the controls(19.8% vs 40.8%, RR=0.36, p=0.01). No significant difference was found in the distributions of the other HLA-DRB1 gene-encoded antigens between the two groups. CONCLUSION: HLA-DRB1 genes may be involved in the development of citrus red mite-induced asthma. In addition, HLA-DR7 may increase, and DR4 decrease, the risk of developing asthma in exposed individuals.

Prevalence of allergic rhinitis and its causative allergens in people in rural area of Cheju IsIand / 천식및알레르기

OBJECTIVE: Cross-sectional survey was performed to evaluate prevalence of allergic rhinitis and its causative allergens in people in rural area of Cheju Isl~and. Subject and METHOD: A total of 1,236 people with 1,055 children and 181 adults in rural area of Cheju Island were enrolled in this study. In children, 544 were males and 511 were females, and their mean age was 12.3(ranging from 7 to 16) years. In adults, 78 were males and 103 were females, and their mean age was 50.1 (ratging from 18 to 87) years. Evaluations included a questionnaire survey, and skin prick test with extracts of Japanese cedar (Cryptomera japonica, J cedar) pollen and citrus red mite (Panonychus citri, CRM) as well as eleven common inhalant allergens. RESULTS: Prevalence of chronic nasal symptoms was 40.6% (429/1,055) in children, and 45.8 % (83/181) in adults. Prevalence of allergic rhinitis based on positive nasal symptoms on the questionnaire and positive skin response to one or more of the 13 inhalant allergens were 15.4 % (159/1.035) in children, and 19.3% (35/181) in adults. Of 1,035 children, skin-test response was positive in 37.6%, and common sensitizing allergens in order of decreasing frequency were Dermatophagoides pteronpssinus (DP) (26.6%), D. farinae (DF)(22.6%), CRM(14.2%), cockroach(11.3%) and J cedar(9.7%). Of 181 adults, skin-test response was positive in 25.9%, and t,he most common sensitizing allergen was CRM(16.5%), followed by cockroach(11.0%), DP(9. 9%), DF(9.4%), and J cedar(6.6%). Of 159 children with allergic rhinitis, the common sensitizing allergens in order of deereasing frequency were DP(79.2%), DF(67.3%), CRM(35.8%), J cedar(32.7%), and cockroach(27.0%). Of 35 adults with allergic rhinitis, the most common sensitizing allergen was CRM(68.6%), followed by DP(40%), DF(34.3%), cockroach(34.3%), and J cedar(28.9%). CONCLUSION: Allergic rhinitis is a very common disease with a prevalence of 15.4% in children and 19.3% in adults in rural area of Cheju island, and common sensitizing allergens include house dust mite, citrus red mite, cockroach, and Japanese cedar pollen.