Molecular Investigation Confirms Myotis Genus Bats as Common Hosts of Polychromophilus in Brazil.

Plasmodium spp. and some other blood parasites belonging to the order Haemosporida are the focus of many epidemiological studies worldwide. However, haemosporidian parasites from wild animals are largely neglected in scientific research. For example, Polychromophilus parasites, which are exclusive to bats, are described in Europe, Asia, Africa, and Oceania, but little is known about their presence and genetic diversity in the New World. In this study, 224 samples of bats from remaining fragments of the Atlantic Forest and Pantanal biomes, as well as urbanized areas in southern and southeastern Brazil, were analyzed for the presence of haemosporidian parasites by PCR of the mitochondrial gene that encodes cytochrome b (cytb). The PCR fragments of the positive samples were sequenced and analyzed by the Bayesian inference method to reconstruct the phylogenetic relationships between Polychromophilus parasites from bats in Brazil and other countries. Sequences from Brazilian lineages of Polychromophilus were recovered in a clade with sequences from Polychromophilus murinus and close to the one Polychromophilus sequence obtained in Panama, the only available sequence for the American continent. This clade was restricted to bats of the family Vespertilionidae and distinct from Polychromophilus melanipherus, a parasite species mainly found in bats of the family Miniopteridae. The detection of Polychromophilus and the genetic proximity to P. murinus were further confirmed with the amplification of two other genes (clpc and asl). We also found a Haemosporida parasite sequence in a sample of Noctilio albiventris collected in the Pantanal biome, which presents phylogenetic proximity with avian Haemoproteus sequences. Morphological and molecular studies are still needed to conclude and describe the Polychromophilus species in Brazilian Myotis bats in more detail and to confirm Haemoproteus parasites in bats. Nevertheless, these molecular results in Brazilian bats confirm the importance of studying these neglected genera.

Novel duplex RT-qPCR for animal rabies surveillance.

Rabies is a lethal zoonosis affecting mammals worldwide. Diagnosis of rabies follows international standard protocols, primarily relying on direct immunofluorescence (DI) followed by mouse inoculation test (MIT). WHO recommends molecular biology techniques such as RT-qPCR for replacing MIT to diagnose rabies in animal samples. Recently, a real-time PCR protocol that detects all rabies virus variants identified worldwide was validated. This assay is a pan-Lyssavirus TaqMan quantitative RT-PCR called LN34. A modified LN34 assay protocol was tested at the Paraná State Reference Laboratory (Lacen/PR) using animal samples previously tested by DI and MIT, the gold standard (GS). This method has been changed to a RT-qPCR duplex format to better fit the diagnostic routine. The new assay was called duplex LN34 and ß-actin RT-qPCR. All the 88 samples evaluated using the GS test, modified pan-Lyssavirus TaqMan RT-qPCR and duplex LN34 and ß-actin RT-qPCR showed 100% agreement with each other. This novel duplex RT-qPCR protocol has shown adequate diagnostic performance and may be used in research and surveillance purposes, replacing the standard MIT and ending mice use for rabies diagnosis.

First Molecular Detection of Polychromophilus Parasites in Brazilian Bat Species.

Blood parasites of the Haemosporida order, such as the Plasmodium spp. responsible for malaria, have become the focus of many studies in evolutionary biology. However, there is a lack of molecular investigation of haemosporidian parasites of wildlife, such as the genus Polychromophilus. Species of this neglected genus exclusively have been described in bats, mainly in Europe, Asia, and Africa, but little is known about its presence and genetic diversity on the American continent. Here, we investigated 406 bats from sites inserted in remnant fragments of the Atlantic Forest and Cerrado biomes and urbanized areas from southern Brazil for the presence of Polychromophilus species by PCR of the mitochondrial cytochrome b encoding gene. A total of 1.2% of bats was positive for Polychromophilus, providing the first molecular information of these parasites in Myotis riparius and Eptesicus diminutus, common vespertilionid bats widely distributed in different Brazilian biomes, and Myotis ruber, an endangered species. A Bayesian analysis was conducted to reconstruct the phylogenetic relationships between Polychromophilus recovered from Brazilian bats and those identified elsewhere. Sequences of Brazilian Polychromophilus lineages were placed with P. murinus and in a clade distinct from P. melanipherus, mainly restricted to bats in the family Vespertilionidae. However, the sequences were split into two minor clades, according to the genus of hosts, indicating that P. murinus and a distinct species may be circulating in Brazil. Morphological observations combined with additional molecular studies are needed to conclude and describe these Polychromophilus species.

Aortic stenosis with abnormal eccentric left ventricular remodeling secondary to hypothyroidism in a Bourdeaux Mastiff / Estenose aórtica com remodelamento excêntrico anormal do ventrículo esquerdo secundário ao hipotireoidismo em um cão Dogue de Bordeaux

ABSTRACT: This paper describes a case of congenital aortic stenosis with eccentric left ventricular hypertrophy associated with hypothyroidism in a 1-year-old Bourdeaux Mastiff dog. The dog had ascites, apathy, alopecic and erythematous skin lesions in different parts of the body. A two-dimensional echocardiogram revealed aortic valve stenosis, with poststenotic dilation in the ascending aorta. The same exam showed eccentric hypertrophy and dilation of the left ventricle during systole and diastole. Aortic stenosis usually results in concentric left ventricular hypertrophy instead of eccentric hypertrophy; and therefore, this finding was very unusual. Hypothyroidism, which is uncommon in young dogs, may be incriminated as the cause of ventricular dilation, making this report even more interesting. Because hypothyroidism would only result in dilatation, the eccentric hypertrophy was attributed to pressure overload caused by aortic stenosis. Thus, cardiac alterations of this case represent a paradoxical association of both diseases.

RESUMO: Este trabalho descreve um caso de estenose aórtica congênita com hipertrofia excêntrica do ventrículo esquerdo associado ao hipotireoidismo em um cão Dogue de Bordeaux. O cão, de um ano de idade, apresentava ascite, apatia, lesões cutâneas alopécicas e eritematosas generalizadas. Na ecocardiografia bidimensional foi observada estenose da valva aórtica, com dilatação pós-estenótica em aorta ascendente. Foi detectado, no mesmo exame, hipertrofia excêntrica e dilatação do ventrículo esquerdo em sístole e diástole. Usualmente, como consequência, a estenose aórtica causa hipertrofia concêntrica do ventrículo esquerdo e não hipertrofia excêntrica, sendo este achado infrequente em tal cardiopatia. O hipotireoidismo, incomum em cães jovens, pode representar a causa da dilatação ventricular observada, o que torna mais relevante esse relato. Como no hipotireoidismo é esperado apenas dilatação, a hipertrofia excêntrica supostamente é atribuída à sobrecarga de pressão causada pela estenose aórtica. Dessa forma, as alterações cardíacas deste caso representam uma associação paradoxal das duas afecções.