Socio-environmental profile of child and adolescents sensitized by house dust mite in northeast of Brazil.

INTRODUCTION: The association regarding the atopic sensitization to mite aeroallergens and the socio-environmental features is still inconsistent. OBJECTIVES: We analyzed the role played by socioeconomic and environmental factors in the prevalence of sensitization to house dust mite (HDM) allergens, and associated with the risk of developing asthma symptoms. PATIENTS AND METHODS: This is a case-control study conducted with 108 patients, aged 1-17. We inquired about family habits, socioeconomic and environmental features. We applied the International Study of Asthma and Allergies in Childhood questionnaire. RESULTS: We observed patients sensitized to all HDM tested, Derp (42%), Derf (37%) and Blot (33%). Middle family income (OR: 2.74; CI95%: 1.127-6.684), exposure to dog (OR: 3.758, CI95%: 1.127-6.684) and artificial climatization (OR: 4.319, CI95%: 1.398-13.348) were associated with sensitization to Derp. We also observed protective factors, such as sharing of dormitories, washing cycle for bedspreads and the presence of basic sanitation. An increased risk of sensitization to Derf was associated with Blot sensitization (OR: 3.172, CI95%: 1.083-9.292) and presence of mold on the walls (OR: 3.095, CI95%: 1.063-9.008). A protective factor was dormitory sharing. For sensitization to Blot, we observed an increase in the risk associated with Derp sensitization (OR: 3.462, CI95%: 1.191-10.061) and exposure to dog (OR: 3.255, CI95%: 0.987-10.736). In addition, sensitization to Blot increases the risk of developing asthma symptoms (OR: 2.732, CI95%: 0.981-7.606). CONCLUSION: Our data show distinct sociodemographic and environmental relations that lead to HDM sensitization and increased probability of development of allergic diseases.

Central drive and ventilatory failure in late-onset Pompe disease: At the gates of a new phenotype.

Subjects with late-onset Pompe disease (LOPD) typically present as slowly progressive proximal muscle weakness. Respiratory muscle weakness and diaphragmatic paralysis are common features, and may be the initial manifestation of the disease. There is often a poor correlation between the severity of limb and respiratory muscle weakness. Early clinical observations about disproportionate hypercapnia to the respiratory muscular weakness in late-onset Pompe disease were recognized and will be discussed with special reference to blunted respiratory drive, and the connections between early clinical observations, respiratory functional studies and anatomical findings. According to new evidence about blunted respiratory drive in Pompe disease, it is necessary to rethink what is meant by "asymptomatic Pompe disease" and propose a new phenotype with its therapeutic implications. The conceptual model of the mechanisms leading to respiratory failure in this disease could be considered according to these new findings. It may broaden the diagnostic spectrum of the adult forms and warrants a closer interaction between neurologists and pulmonologists. The recognition of this new phenotype of predominant central alveolar hypoventilation in Pompe disease will improve the understanding of the underlying mechanisms of ventilatory failure and could lead to improved future therapeutic strategies.

Meriones unguiculatus infected by Haemonchus contortus: evaluation of different experimental protocols.

Many important studies on resistance reversion, anthelmintic efficacy and, especially, new molecules with antiparasitic effects are performed in laboratories using gerbils (Meriones unguiculatus) as the experimental model. This study aimed to evaluate the use of corticosteroids (dexamethasone and methylprednisolone acetate) in gerbils experimentally infected with different doses of infective larvae (sheathed or exsheathed) of Haemonchus contortus. In the first experiment, 28 gerbils were divided into seven groups infected by 2-6 × 103 larvae, with or without immunosuppression using corticosteroids. In the second experiment, eight gerbils were divided into two groups infected by 2 × 103 sheathed or exsheathed larvae. For the third assay, seven immunosuppressed gerbils were infected with 2 × 103 sheathed larvae and were killed 15 days post infection (PI). The highest number of parasites was recovered from methylprednisolone-immunosuppressed animals. We observed red and white blood cell alterations and biochemical parameters in infected animals that had undergone immunosuppression with methylprednisolone. We highlight that in the first and second experiments a satisfactory number of worms was recovered using sheathed larvae and immunocompetent animals. When exsheathed larvae were used, the number of worms recovered was unsatisfactory. A considerable larval burden was recovered from immunosuppressed gerbils 15 days PI, and body weight did not influence establishment of larvae.

Serum adenosine deaminase and xanthine oxidase activities in silver catfish naturally infected with Ichthyophthirius multifiliis: The influence of these enzymes on inflammatory and oxidative status.

Adenosine deaminase (ADA) activity, through adenosine (Ado) levels, as well as xanthine oxidase (XO) activity through uric acid levels exerts an essential role on immune and inflammatory responses during infectious diseases. Thus, the aim of this study was to evaluate the involvement of seric ADA and XO activities in the inflammatory and oxidative status of silver catfish naturally infected with Ichthyophthirius multifiliis. Seric ADA activity decreased, while Ado levels increased in infected animals compared to uninfected animals. Moreover, the seric XO activity increased in infected animals compared to uninfected animals, alongside the seric levels of uric acid, metabolites of nitric oxide (NOx) and reactive oxygen species (ROS). Based on this evidence, the downregulation of seric ADA activity exerts an anti-inflammatory profile, contributing to restricting the inflammatory process. The most important finding is that upregulation of seric XO activity leads to an excessive formation of uric acid, which contributes to oxidative and inflammatory processes. Moreover, uric acid induces the release of pro-inflammatory and pro-oxidative mediators, such NOx and ROS, which contribute directly to disease pathogenesis. In summary, the upregulation of XO activity may be considered a pathway involved in NOx and ROS production in silver catfish infected with I. multifiliis.

In vitro activity of essential oils of free and nanostructured Melaleuca alternifolia and of terpinen-4-ol on eggs and larvae of Haemonchus contortus.

Haemonchus contortus is one of the major gastrointestinal nematodes responsible for significant economic and production losses of sheep. Diseases caused by this species lack effective anthelmintic products, and the search for new compounds to replace synthetic anthelmintics has been extensive. The present investigation assesses the in vitro activity of the essential oil of melaleuca (Melaleuca alternifolia), both free (TTO) and nanostructured (nanoTTO), and terpinen-4-ol (terp-4-ol) on eggs and larvae of H. contortus. Tests of egg hatching (EHT) and inhibition of larval migration (LMIT) were used to assess the in vitro efficacy of TTO, nanoTTO and terp-4-ol. Using EHT, at a concentration of 3.5 mg/ml, 100% inhibition occurred using TTO and terp-4-ol, with LC50 values of 0.43 and 0.63 mg/ml, and LC90 values of 1.75 mg/ml and 3.12 mg/ml, respectively. NanoTTO had lower activity, with 82.6% inhibition at the same concentration. Using LMIT, TTO and nanoTTO had a similar activity with 88.0% and 84.8% inhibition, respectively, at a concentration of 56 mg/ml. Terp-4-ol had a greater effect on larvae, with 85.7% inhibition at a concentration of 56 mg/ml and 82.4% at 3.5 mg/ml, demonstrating high activity at the lowest concentration tested. Therefore, the results indicate that all substances tested showed ovicidal and larvicidal activity against H. contortus. TTO, terp-4-ol and, mainly, nanoTTO may be targeted in in vivo studies, besides being a promising line of research into the control and treatment of veterinary important helminths.

Antimutagenic action of the triterpene betulinic acid isolated from Scoparia dulcis (Scrophulariaceae).

The mutagenic and antimutagenic activities of triterpene betulinic acid {3b-3-hydroxy-lup-20(29)-en-28-oic} isolated from the roots of Scoparia dulcis (Scrophulariaceae) were analyzed using the somatic mutation and recombination test (SMART) in the wings of Drosophila melanogaster. The mutagenic potential of betulinic acid was evaluated at 3 different concentrations (1.64, 3.28, and 6.57 mM). Antimutagenic activity evaluation was performed by co-treatment trials in which the flies received betulinic acid at 3 different concentrations in addition to 10 mM pro-mutagenic urethane. The results demonstrated that betulinic acid was not capable of causing DNA damage. However, the frequency of small single spots, large spots, and twin spots was significantly reduced. In the high bioactivation cross, betulinic acid was significantly active and exerted enhanced antimutagenic activity, possibly as a desmutagen.

Trypanocidal activity of free and nanoencapsulated curcumin on Trypanosoma evansi.

This study aimed to evaluate in vitro and in vivo trypanocidal activity of free and nanoencapsulated curcumin against Trypanosoma evansi. In vitro efficacy of free curcumin (CURC) and curcumin-loaded in lipid-core nanocapsules (C-LNCs) was evaluated to verify their lethal effect on T. evansi. To perform the in vivo tests, T. evansi-infected animals were treated with CURC (10 and 100 mg kg(-1), intraperitoneally [i.p.]) and C-LNCs (10 mg kg(-1), i.p.) during 6 days, with the results showing that these treatments significantly attenuated the parasitaemia. Infected untreated rats showed protein peroxidation and an increase of nitrites/nitrates, whereas animals treated with curcumin showed a reduction on these variables. As a result, the activity of antioxidant enzymes (superoxide dismutase and catalase) differs between groups (P<0.05). Infected animals and treated with CURC exhibited a reduction in the levels of alanine aminotransferase and creatinine, when compared with the positive control group. The use of curcumin in vitro resulted in a better parasitaemia control, an antioxidant activity and a protective effect on liver and kidney functions of T. evansi-infected adult male Wistar rats.

Levels of mannose-binding lectin in individuals with visceral leishmaniasis in the northeast region of Brazil.

Visceral leishmaniasis (VL) is one of the seven priority endemic diseases in the world. The clinical outcome of many infections is not only dependent on the pathogenic organism, but also on the genetic variability of the host susceptibility to infection. Mannose-binding lectin (MBL) is a protein that plays an important role in the innate immune system. The aim of this study was to compare the serum levels of MBL between healthy controls and carriers of VL. The VL cases were recruited randomly from the main hospitals and referral outpatient clinics for VL in São Luís, and from home visits. Determination of MBL protein levels was performed by enzyme-linked immunosorbent assay. Of the 161 patients with VL and the 161 healthy controls, 60.9 and 67.1% had high levels of MBL, respectively. There was no significant difference in MBL levels between cases and controls. Low socioeconomic status and living conditions are conducive to the occurrence of VL. Owing to the small number of existing studies, it is extremely important to conduct further studies on MBL levels and susceptibility to VL, especially in regions where the disease is endemic, such as Maranhão, Brazil.

Contrasting patterns of within-species morphological variation in two cactophilic Drosophila species (Diptera: Drosophilidae).

In this work, we investigated the morphological variation of the intromittent male copulatory organ (aedeagus) of specimens from natural populations of two cactophilic Drosophila species distributed in the southeast region of Brazil, Drosophila gouveai Tidon-Sklorz & Sene and Drosophila antonietae Tidon-Sklorz & Sene. It was explored how the within-species variability is arranged for both species, considering their historical and ecological features. Our results showed two distinct aedeagal morphologies for these species, and differences within species were observed only in D. gouveai as specimens could be distinguished by their population origin. In contrast, after size discrepancies correction, this feature was not detected in D. antonietae. The contrasting patterns of intraspecific variation, together with the other features exhibited by these two species, are most likely to be explained by differences in the historical host plant association and distribution and in demographic events, which determined the evolutionary history of these two South American cactophilic Drosophila species.

Activity of cholinesterases and adenosine deaminase in blood and serum of rats experimentally infected with Trypanosoma cruzi.

This study aimed to evaluate the activity of cholinesterases and adenosine deaminase (ADA) in blood and serum of rats infected with Trypanosoma cruzi. Twelve adult rats were used in the experiment divided into two uniform groups. Rodents from group A (control group) were non-infected and animals from group B served as infected, receiving intraperitoneally 3·3×10(7) trypomastigotes/each. Blood collection was performed at days 60 and 120 post-infection (PI) in order to evaluate the hemogram, blood activity of acetylcholinesterase, and serum butyrylcholinesterase and ADA activities. Hematological parameters did not differ between groups. A significant increase (P<0·05) of acetylcholinesterase activity was observed in blood while butyrylcholinesterase had a significant reduction (P<0·01) in serum of infected rats at days 60 and 120 PI. ADA activity in serum showed an inhibition in infected animals when compared to non-infected at day 120 PI. Based on these results, it is possible to conclude that the activity of cholinesterases and ADA were changed in animals infected with T. cruzi. The possible causes of these alterations will be discussed in this paper.

A suitable model for the utilization of Duddingtonia flagrans fungus in small-flock-size sheep farms.

Effective alternatives to anthelmintic treatment of nematode parasite infections of sheep are required because of the high prevalence of drug resistance. Within this context, the nematode-trapping fungus Duddingtonia flagrans has become a valuable component of various integrated control strategies. Toward this objective, a small quantity of lyophilized D. flagrans chlamydospores (10(6) spores per animal) was administered to sheep in a one-year plot study. Animals grazing on native pasture were divided into two homogeneous groups and were kept in 1-ha paddocks in the southern region of Brazil. The oral administration of chlamydospores led to a significant reduction (p<0.05) in the number of nematode eggs per gram of feces and in the larval availability on herbage (difference of 37.6%) in comparison to the control group. Control animals needed to be dewormed three times during the experiment, whereas the fungus-treated animals maintained a low parasite load, independent of seasonal variation. Although D. flagrans cannot serve as a panacea for nematode parasite control of livestock, it represents a significant advance toward rationalizing the use of endoparasitic drugs in small animals.

Relationship between splenic sequestration and thrombocytopenia in Trypanosoma evansi infection in rats.

Trypanosoma evansi infections in domestic animals are characterized by anemia and thrombocytopenia. The cause of the platelets decrease is unknown, but researchers suggest that thrombocytopenia may result from damage of the bone marrow, reduced survival of platelets, auto-immune thrombocytopenia, disseminated intravascular coagulation and splenic sequestration. Some of these causes have already been tested by our research group and found to be unrelated. Therefore, this study has the objective of testing the hypothesis that splenic sequestration might be responsible for thrombocytopenia in T. evansi-infected rats. A total of 28 rats assigned to four groups were used in the experiment. Group A rats were splenectomized and infected with T. evansi, group B rats were infected with T. evansi, group C rats were splenectomized, but not infected and group D rats were normal controls. Five days post-infection all rats were anesthetized and blood was collected in order to measure the number of circulating platelets, fibrinogen levels, prothrombin time (PT) and activated partial thromboplastin time (aPTT). The spleens of groups B and D were weighed at necropsy. The infected animals (groups A and B) showed a significant reduction in platelets and increased PT and aPTT when compared to negative control groups (groups C and D). Animals from group A showed increased levels of fibrinogen. The mean weight of spleen differed between group B (2.62g) and group D (0.55g). It was concluded that there is no relationship between thrombocytopenia and splenic sequestration in infection by T. evansi.

Pathological findings associated with experimental infection by Trypanosoma evansi in cats.

Five cats were experimentally inoculated with Trypanosoma evansi in order to evaluate the pathological changes induced by this protozoan infection. Clinical signs observed included vomiting, diarrhoea, hyperthermia, weight loss, facial oedema, corneal opacity, lymphadenopathy and hindlimb instability. Reduction in hematocrit was observed from 7 days post-infection (dpi) (P<0.05). One cat died at 40 dpi and the other four cats were humanely destroyed. Necropsy examination was performed in two cats at 56 dpi and two cats at 120 dpi. Gross findings in all cats included generalized muscle atrophy, pale mucosae, icterus of the subcutaneous and serosal tissue and the intima of arteries, lymphadenopathy and splenomegaly. Other findings included corneal opacity, subcutaneous oedema (mainly of the head) and hydropericardium. Trypomastigotes of T. evansi were observed in impression smears prepared from the aqueous humor. Microscopically, there was lymphoid hyperplasia of the spleen and lymph nodes. The animals with corneal opacity had mild corneal oedema and accumulation of fibrin and inflammatory cells (neutrophils and plasma cells) in the anterior chamber. Similar inflammatory cells infiltrated the iris, ciliary body, corneoscleral limbus and conjunctiva.

Influence of Trypanosoma evansi in blood, plasma, and brain cholinesterase of experimentally infected cats.

Changes in blood, plasma and brain cholinesterase activities in Trypanosoma evansi-infected cats were investigated. Seven animals were infected with 10(8) trypomastigote forms each and six were used as control. Animals were monitored for 56 days by examining daily blood smears. Blood samples were collected at days 28 and 56 post-inoculation to determine the activity of acetylcholinesterase (AChE) in blood and the activity of butyrylcholinesterase (BChE) in plasma. AChE was also evaluated in total brain. The activity of AChE in blood and brain, and the activity of BChE in plasma significantly reduced in the infected cats. Therefore, the infection by T. evansi influenced cholinesterases of felines indicating changes in the responses of the cholinergic system.

Diminazene aceturate in the control of Trypanosoma evansi infection in cats.

The aim of this study was to investigate the efficacy of diminazene aceturate in the control of the infection by Trypanosoma evansi in cats. Fourteen animals were infected with 10(8) trypomastigote forms each and six were used as negative control (group A). Seven of the infected cats were used as positive control (group B) and seven were treated with diminazene aceturate (3.5 mg kg(-1)) for 5 consecutive days (group C). Biochemical and hematological parameters were evaluated during the experiment. Blood with anticoagulant was collected at day 49 post-inoculation and preserved in ethanol for DNA extraction. Samples were analyzed using PCR T. evansi-specific to assess the effectiveness of treatment. The treatment with diminazene aceturate had an efficacy of 85.7%. Alanine aminotransferase, gamma-glutamyltransferase, urea, and creatinine values remained within the normal physiological range in the treated cats. Hemogram was normalized in all the cured animals. Therefore, the therapy used is effective in controlling T. evansi in cats.

Efeito do isolado 986 do fungo Beauveria bassiana (Bals) Vuill sobre fêmeas ingurgitadas de Anocentor nitens Neumann, 1897 (Acari: Ixodidae) / Effect of isolate 986 of the fungi Beauveria bassiana (Bals) Vuill on engorged females of Anocentor nitens Neumann, 1897 (Acari: Ixodidae)

Fêmeas ingurgitadas de Anocentro nitens foram colhidas de eqüinos infestados para determinar a influência do fungo Beauveria bassiana (isolado 986) na fase näo parasitária do carrapato. Grupos de 20 fêmeas foram utilizados para testar suspensöes que continham água destilada, espalhante adesivo e diferentes concentraçöes de conídios (10 elevado a quinta potência, 10 elevado a sexta potência, 10 elevado a sétima potência e 10 elevado a oitava potência conídios/ml), mais um grupo-controle. As fêmeas foram imersas nas suspensöes por três minutos, acondicionadas em placas de Petri e levadas a câmara climatizada (27ºC e 80 por cento UR). Com exceçäo do período de pré-postura e do percentual de eclosäo das larvas, os resultados revelaram diferenças significativas entre os grupos tratados e o controle. Nos grupos tratados obrservou-se diminuiçäo gradativa, inversamente proporcional às concentraçöes de conídios, no período de postura, no peso da massa de ovos, no período médio de sobrevivência, no período de incubaçäo, no período de eclosäo e nos índices de eficiência reprodutiva e nutricional. Contrariamente, houve aumento gradativo, diretamente proporcional às concentraçöes, no peso da quenógina e na mortalidade de larvas. Entretanto, näo foi observada interferência sobre o percentual de eclosäo. Os resultados obtidos permitem concluir que B. bassiana pode ser utilizada em programas de controle biológico de fêmeas de A. nitens