Evolution and divergence of the genetic lineage Desmodus rotundus/Artibeus lituratus of rabies virus in São Paulo State.

The last record of a rabies case caused by the dog-specific rabies virus (RABV) lineage in dogs or cats in São Paulo State was in 1998. From 2002 to 2021, 57 cases of rabies in these animals were reported, and the vast majority (51) were genetically characterized as belonging to the Desmodus rotundus/Artibeus lituratus RABV lineage. However, it is not currently possible to infer which of these bats is the source of infection by genome sequencing of RABV isolates. The aims of this study were (a) to characterize the Desmodus rotundus/Artibeus lituratus lineage to determine the relationships between the RABV lineages and each reservoir, (b) to assess the phylogeny and common ancestors of the RABV lineages found in D. rotundus and A. lituratus, and (c) to further understand the epidemiology and control of rabies. In this study, we genetically analyzed 70 RABV isolates from São Paulo State that were received by the Virology Laboratory of the Pasteur Institute of São Paulo between 2006 and 2015. Of these isolates, 33 were associated with the hematophagous bat D. rotundus and 37 with the fruit bat A. lituratus. A genomic approach using phylogenetic analysis and nucleotide sequence comparisons demonstrated that these isolates belonged to the same genetic lineage of RABV. We also found that, in São Paulo State, the D. rotundus/A. lituratus lineage could be subdivided into at least four phylogenetic sublineages: two associated with D. rotundus and two with A. lituratus. These results are of importance for the epidemiological surveillance of rabies in São Paulo.

The Epidemiological Importance of Bats in the Transmission of Rabies to Dogs and Cats in the State of São Paulo, Brazil, Between 2005 and 2014.

In Brazil, rabies control in dogs and cats was pioneered by the state of São Paulo with the adoption of the Pan American Health Organization recommendations for prophylaxis and control, which led to a reduction in rabies cases from 1994 onwards. As a result of these measures, the rabies virus (RABV) genetic lineage associated with dogs has not been found in the state since 1998, and all the cases in domestic animals reported since then have been caused by bat-associated lineages of RABV. In the light of this, this study sought to investigate rabies cases in dogs and cats in the state of São Paulo between 2005 and 2014 and identify the associated transmission cycles by characterizing the RABV lineages responsible for these cases. Nine samples from dogs (n = 5) and from cats (n = 4) were collected between 2005 and 2014. The tenth animal, a rabid cat, was analysed by a different laboratory. The N gene nucleotide sequences obtained were analysed with the neighbor-joining algorithm and Kimura 2-parameter model using the MEGA 6 program. Phylogenetic analysis revealed that the genetic lineages identified in all the samples were those circulating in Brazilian bats. The findings of this study demonstrate that bats play an important role in the transmission of rabies to domestic animals in São Paulo state and that emphasis should be placed on the implementation of public policies to support surveillance of chiropterans for rabies.

Ion release and mechanical properties of calcium silicate and calcium hydroxide materials used for pulp capping.

AIM: To compare the ion release and mechanical properties of a calcium hydroxide (Dycal) and two calcium silicate (MTA Angelus and Biodentine) cements. METHODOLOGY: Calcium and hydroxyl ion release in water from 24-h set cements were calculated from titration with HCl (n = 3). Calcium release after 7, 14, 21 and 28 days at pH 5.5 and 7.0 was measured using ICP-OES (n = 6). Flexural strength (FS) and modulus (E) were tested after 48-h storage, and compressive strength (CS) was tested after 48 h and 7 days (n = 10). Ion release and mechanical data were subjected to anova/Tukey and Kruskal-Wallis/Mann-Whitney tests, respectively (α = 0.05). RESULTS: Titration curves revealed that Dycal released significantly fewer ions in solution than calcium silicates (P < 0.001). Calcium release remained constant at pH 7.0, whilst at pH 5.5, it dropped significantly by 24% after 21 days (P < 0.05). At pH 5.5, MTA Angelus released significantly more calcium than Dycal (P < 0.01), whilst Biodentine had superior ion release than Dycal at pH 7.0 (P < 0.01). Biodentine had superior flexural strength, flexural modulus and compressive strength than the other cements, whilst MTA Angelus had higher modulus than Dycal (P < 0.001). CONCLUSIONS: Immediate calcium and hydroxyl ion release in solution was significantly lower for Dycal. In general, all materials released constant calcium levels over 28 days, but release from Dycal was significantly lower than Biodentine and MTA Angelus depending on pH conditions. Biodentine had substantially higher strength and modulus than MTA Angelus and Dycal, both of which demonstrated low stress-bearing capabilities.

A study of some parameters in stimulated saliva from adolescents with dental fluorosis.

In this study, parameters such as the flow rate, buffer capacity, sialic acid, protein and electrolyte concentrations, and amylase and peroxidase activities were analyzed in stimulated whole saliva from adolescents with dental fluorosis. From 135 adolescents (13 and 14 years-old) attending a primary and secondary school in the coastal city of Vitoria-Brazil, 72 were selected to participate in this study. The degree of fluorosis was graded using the TSIF, and was carried out by a calibrated and trained dentist. No variation in the flow rate, pH and buffer capacity, protein concentration or amylase activity was observed between the groups with dental fluorosis and the control group (fluorosis score 0). The peroxidase activity and sialic acid concentration showed some differences compared to the control. Sialic acid concentrations were reduced in the groups with dental fluorosis scores above 2. The concentration of Na was lower in adolescents with dental fluorosis, while Mg concentrations were higher in two fluorosis groups, Ca concentration was reduced in two groups with fluorosis. We conclude, that 13 and 14 year-old adolescents attending a school in the coastal city of Vitoria-Brazil showed no variations relative to some parameters and some variations in relation to others of the salivary parameters studied.

Pilocarpine-induced increases in the activity of 6-phosphofructo-2-kinase and the fructose-2,6-bisphosphate content of rat salivary glands.

The activity of 6-phosphofructo-1-kinase (PFK-1), an important regulatory enzyme of glycolysis, was determined after injection of the sialagogue pilocarpine. The fructose-2,6-bisphosphate content of the glands and 6-phosphofructo-2-kinase (PFK-2) activity were also measured. The increase in PFK-1 activity after pilocarpine treatment was likely to be due to the increase in the content of its potent modulator, fructose-2,6-bisphosphate. This in turn was assumed to be due to the increase in the activity of the active form of PFK-2.