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Background: Mosquito-borne diseases are rapidly spreading to vast territories, putting at risk most of the world's population. A key player in this scenario is Aedes aegypti, a hematophagous species which hosts and transmits viruses causing dengue and other serious illnesses. Since vector control strategies relying only on insecticides have proven unsustainable, an alternative method involving the release of Wolbachia-harboring individuals has emerged. Its successful implementation vastly depends on how fit the released individuals are in the natural habitat, being able to mate with wild populations and to spread Wolbachia to subsequent generations. In mosquitoes, an important aspect of reproductive fitness is the acoustic communication between males and females, which translates to interactions between harmonic frequencies in close proximity flight. This study aimed to characterize the flight tone produced by individuals harboring Wolbachia, also evaluating their ability to establish stable acoustic interactions. Methods: Wild-type (WT) and Wolbachia-harboring specimens (wMelBr) were thorax-tethered to blunt copper wires and placed at close proximity to sensitive microphones. Wing-beat frequencies (WBFs) were characterized at fundamental and harmonic levels, for both single individuals and couples. Harmonic interactions in homogeneous and heterogeneous couples of WT and wMelBr variants were identified, categorized and quantified accordingly. Results: In tethered 'solo' flights, individuals harboring Wolbachia developed WBFs, differing slightly, in a sex-dependent way, from those of the WT strain. To test the ability to form harmonic 'duets', tethered couples of wMelBr and WT individuals were shuffled in different sex pairs and had their flight tones analyzed. All couple types, with WT and/or wMelBr individuals, were able to interact acoustically in the frequency range of 1300-1500 Hz, which translates to the convergence between male's second harmonic and female's third. No significant differences were found in the proportions of interacting couples between the pair types. Surprisingly, spectrograms also revealed the convergence between alternative harmonic frequencies, inside and outside the species putative hearing threshold. Conclusions: Wolbachia infection leads to small sex-dependent changes on the flight tones of Ae. aegypti, but it does not seem to prevent the stereotyped harmonic interaction between males and females. Therefore, when released in the natural habitat to breed with native individuals, Wolbachia-harboring individuals shall be fit enough to meet the criteria of acoustically-related mating behavior and promote bacteria dispersion effectively. [ABSTRACT FROM AUTHOR]

Evaluation of the malignant potential of a pheochromocytoma (PCC) remains controversial. PCC is regarded as a neuroendocrine tumor (NET), and the classification of NETs has gradually been defined over the last decade, particularly for gastroenteropancreatic NET. The present study describes a case of locally advanced, carcinoma-like, nonfunctional PCC, which may be regarded as neuroendocrine carcinoma (NEC) rather than a malignant PCC. A 72-year-old man was referred to Saitama Red Cross Hospital (Saitama, Japan), presenting with a 2-month history of right flank pain. Computed tomography revealed a right adrenal gland tumor, which measured 6.0 cm in diameter, invading the hilum of the right kidney, liver and inferior vena cava (IVC). Radical surgery was performed with en bloc resection of the right kidney, and adjacent parts of the liver and IVC. Immunohistochemical examination demonstrated that all of the resected tissues were positive for cytokeratin AE1/AE3, chromogranin A, synaptophysin, cluster of differentiation 56 and Ki-67, and the specimen had a Ki-67 index of 80%. A diagnosis of carcinoma-like PCC or NEC of the adrenal gland was confirmed. Reports of NEC of the adrenal gland are extremely rare in the literature, and classification of PCC as a NET has not yet been fully discussed. The present case may therefore contribute to the classification of NETs in the adrenal gland. [ABSTRACT FROM AUTHOR]

Background The chemical control of the mosquito Aedes aegypti, the major vector of dengue, is being seriously threatened due to the development of pyrethroid resistance. Substitutions in the 1016 and 1534 sites of the voltage gated sodium channel (AaNaV), commonly known as kdr mutations, confer the mosquito with knockdown resistance. Our aim was to evaluate the allelic composition of natural populations of Brazilian Ae. aegypti at both kdr sites. Methods The AaNaV IIIS6 region was cloned and sequenced from three Brazilian populations. Additionally, individual mosquitoes from 30 populations throughout the country were genotyped for 1016 and 1534 sites, based in allele-specific PCR. For individual genotypes both sites were considered as a single locus. Results The 350 bp sequence spanning the IIIS6 region of the AaNaV gene revealed the occurrence of the kdr mutation Phe1534Cys in Brazil. Concerning the individual genotyping, beyond the susceptible wild-type (NaV S), two kdr alleles were identified: substitutions restricted to the 1534 position (NaV R1) or simultaneous substitutions in both 1016 and 1534 sites (NaV R2). A clear regional distribution pattern of these alleles was observed. The NaV R1 kdr allele occurred in all localities, while NaV R2 was more frequent in the Central and Southeastern localities. Locations that were sampled multiple times in the course of a decade revealed an increase in frequency of the kdr mutations, mainly the double mutant allele NaV R2. Recent samples also indicate that NaV R2 is spreading towards the Northern region. Conclusions We have found that in addition to the previously reported Val1016Ile kdr mutation, the Phe1534Cys mutation also occurs in Brazil. Allelic composition at both sites was important to elucidate the actual distribution of kdr mutations throughout the country. Studies to determine gene flow and the fitness costs of these kdr alleles are underway and will be important to better understand the dynamics of Ae. aegypti pyrethroid resistance. [ABSTRACT FROM AUTHOR]