The audiological profile of adults with and without hypertension.

OBJECTIVE: To determine whether there is any influence of systemic arterial hypertension on the peripheral auditory system. METHODS: This was a cross-sectional study that investigated 40 individuals between 30 and 50 years old, who were divided into groups with and without systemic arterial hypertension, using data from high-frequency audiometry, transient-evoked otoacoustic emissions and distortion-product otoacoustic emissions. The results were compared with those from groups of normal-hearing individuals, with and without systemic arterial hypertension, who underwent the pure-tone audiometry test. All individuals also underwent the following procedures: otoscopy, acoustic immittance measures, pure-tone audiometry at frequencies from 250 to 16000 Hz, transient-evoked otoacoustic emissions test and distortion-product otoacoustic emissions test. RESULTS: No statistically significant difference was observed between the groups with and without systemic arterial hypertension in either conventional or high-frequency audiometry. Regarding transient-evoked otoacoustic emissions, there was a trend toward statistical significance whereby the systemic arterial hypertension group showed lower results. Regarding distortion-product otoacoustic emissions, the systemic arterial hypertension group showed significantly lower results at the following frequencies: 1501, 2002, and 3003 Hz. A discriminant analysis indicated that the distortion-product otoacoustic emissions variables best distinguished individuals with and without systemic arterial hypertension. CONCLUSION: Data from this study suggest cochlear dysfunction in individuals with systemic arterial hypertension because their otoacoustic emission results were lower than those in the systemic arterial hypertension group.

The audiological profile of adults with and without hypertension

OBJECTIVE: To determine whether there is any influence of systemic arterial hypertension on the peripheral auditory system. METHODS: This was a cross-sectional study that investigated 40 individuals between 30 and 50 years old, who were divided into groups with and without systemic arterial hypertension, using data from high-frequency audiometry, transient-evoked otoacoustic emissions and distortion-product otoacoustic emissions. The results were compared with those from groups of normal-hearing individuals, with and without systemic arterial hypertension, who underwent the pure-tone audiometry test. All individuals also underwent the following procedures: otoscopy, acoustic immittance measures, pure-tone audiometry at frequencies from 250 to 16000 Hz, transient-evoked otoacoustic emissions test and distortion-product otoacoustic emissions test. RESULTS: No statistically significant difference was observed between the groups with and without systemic arterial hypertension in either conventional or high-frequency audiometry. Regarding transient-evoked otoacoustic emissions, there was a trend toward statistical significance whereby the systemic arterial hypertension group showed lower results. Regarding distortion-product otoacoustic emissions, the systemic arterial hypertension group showed significantly lower results at the following frequencies: 1501, 2002, and 3003 Hz. A discriminant analysis indicated that the distortion-product otoacoustic emissions variables best distinguished individuals with and without systemic arterial hypertension. CONCLUSION: Data from this study suggest cochlear dysfunction in individuals with systemic arterial hypertension because their otoacoustic emission results were lower than those in the systemic arterial hypertension group.

Protective immunity against tick infestation in cattle vaccinated with recombinant trypsin inhibitor of Rhipicephalus microplus.

The cattle tick, Rhipicephalus microplus, is regarded as the most economically important ectoparasite of livestock globally. Control is achieved primarily through the use of acaricides. This approach is hampered by the development of resistance to commercial acaricides among cattle tick populations. Vaccination against R. microplus infestation is another technology that can be integrated for effective cattle tick control. Proteins belonging to the Kunitz-BPTI family are abundant in cattle tick salivary glands, midgut, and ovaries. These organs are attractive targets for the development of a novel cattle tick vaccine. Efficacy assessment against cattle tick infestation in bovines using a vaccine containing the recombinant form of a member of the Kunitz family from R. microplus produced in a yeast expression system is reported for the first time here. The yeast Pichia pastoris was bioengineered to produce the recombinant version of a trypsin inhibitor that is expressed in cattle tick larvae (rRmLTI). Immunization with rRmLTI afforded 32% efficacy against R. microplus. The estimated molecular weight of rRmLTI was 46 kDa. Structural homology to the native form of the larval trypsin inhibitor was documented by recognition of rRmLTI in Western-blots using polyclonal antibodies from mice immunized with cattle tick larval extract or rRmLTI. Bioinformatics analysis of the partial nucleotide and deduced amino acid sequences indicated that the rRmLTI closely resembles BmTI-6, which is a three-headed Kunitz protein present in cattle tick ovary and fat tissue.

Acaricide resistance of Rhipicephalus (Boophilus) microplus in State of Mato Grosso do Sul, Brazil.

This study was conducted to obtain an epidemiological view of acaricide resistance in populations of Rhipicephalus (Boophilus) microplus in the State of Mato Grosso do Sul. Twenty-four tick samples were collected from municipalities in the State where farmers had reported concerns about resistance to or failure of tick control. These ticks were subjected to in vitro resistance detection assays using the adult immersion test (AIT). The efficacy of alpha-cypermethrin, cypermethrin and amitraz treatments on samples collected throughout the State was generally poor. AIT showed efficacy ≥ 90% from the use of DDVP + chlorfenvinphos) (20 out of 21 municipalities), dichlorvos + cypermethrin (10 out of 16 municipalities) and cypermethrin + citronella + chlorpyrifos + piperonyl butoxide (20 out of 21 municipalities). PCR assays were used to detect the presence of pyrethroid resistance-associated sodium channel gene mutation. Larvae from three different populations that had previously been diagnosed as pyrethroid-resistant, through AIT, were evaluated. The PCR assays showed that the pyrethroid resistance-associated gene mutation was absent from these three populations. This study confirms that the emergence of resistance is a constant challenge for the livestock industry, and that development of resistance continues to be a major driver for new antiparasitic drugs to be developed.

Acaricide resistance of Rhipicephalus (Boophilus) microplus in State of Mato Grosso do Sul, Brazil / Resistência do Rhipicephalus (Boophilus) microplus aos acaricidas no Estado de Mato Grosso do Sul, Brasil

This study was conducted to obtain an epidemiological view of acaricide resistance in populations of Rhipicephalus (Boophilus) microplus in the State of Mato Grosso do Sul. Twenty-four tick samples were collected from municipalities in the State where farmers had reported concerns about resistance to or failure of tick control. These ticks were subjected to in vitro resistance detection assays using the adult immersion test (AIT). The efficacy of alpha-cypermethrin, cypermethrin and amitraz treatments on samples collected throughout the State was generally poor. AIT showed efficacy > 90 percent from the use of DDVP + chlorfenvinphos) (20 out of 21 municipalities), dichlorvos + cypermethrin (10 out of 16 municipalities) and cypermethrin + citronella + chlorpyrifos + piperonyl butoxide (20 out of 21 municipalities). PCR assays were used to detect the presence of pyrethroid resistance-associated sodium channel gene mutation. Larvae from three different populations that had previously been diagnosed as pyrethroid-resistant, through AIT, were evaluated. The PCR assays showed that the pyrethroid resistance-associated gene mutation was absent from these three populations. This study confirms that the emergence of resistance is a constant challenge for the livestock industry, and that development of resistance continues to be a major driver for new antiparasitic drugs to be developed.

Este estudo foi realizado com o objetivo de se obter uma visão epidemiológica da resistência aos acaricidas nas populações de Rhipicephalus (Boophilus) microplus no Estado de Mato Grosso do Sul. Vinte e quatro amostras de carrapatos foram coletadas em cidades do estado onde os fazendeiros relataram preocupação com resistência ou falha no controle dos carrapatos. Estes carrapatos foram submetidos a testes de detecção de resistência in vitro usando o teste de imersão de adultos (TIA). A eficácia do tratamento com alfa-cipermetrina, cipermetrina e amitraz foi geralmente pobre nas amostras coletadas em todo o Estado. Obteve-se eficácia de >90 por cento no TIA com o DDVP + chlorfenvinphos (20 das 21 cidades), Diclorvós + Cipermetrina (10 das 16 cidades), e Cipermetrina + Citronela + Clorpirifós + Butóxido de piperonila (20 das 21 cidades). O ensaio da PCR foi utilizado para detectar a presença de mutação do gene do canal de sódio associado à resistência a piretróide. Avaliaram-se larvas de três diferentes populações onde anteriormente foi diagnosticada à resistência por TIA. Os ensaios da PCR mostraram que a mutação no gene associado à resistência ao piretróide estava ausente nessas três populações. Esse estudo confirma que o surgimento da resistência é um constante desafio para a pecuária e o desenvolvimento de resistência continua a ser um importante estímulo para o desenvolvimento de novas drogas antiparasitárias.