Dengue fever is the most prevalent vector-borne disease in the world, with nearly 100 million people infected every year. Early diagnosis and identification of the pathogen are crucial steps for the treatment and for prevention of the disease, mainly in areas where the co-circulation of different serotypes is common, increasing the outcome of dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Due to the lack of fast and inexpensive methods available for the identification of dengue serotypes, herein we report the development of an electrochemical DNA biosensor for the detection of sequences of dengue virus serotype 3 (DENV-3). DENV-3 probe was designed using bioinformatics software and differential pulse voltammetry (DPV) was used for electrochemical analysis. The results showed that a 22-m sequence was the best DNA probe for the identification of DENV-3. The optimum concentration of the DNA probe immobilized onto the electrode surface is 500 nM and a low detection limit of the system (3.09 nM). Moreover, this system allows selective detection of DENV-3 sequences in buffer and human serum solutions. Therefore, the application of DNA biosensors for diagnostics at the molecular level may contribute to future advances in the implementation of specific, effective and rapid detection methods for the diagnosis dengue viruses.

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Investigations of any type of crime invariably starts at the crime scene by collecting evidence. Thus, the purpose of this research was to collect and analyze an entomological trace from an environment that is similar to those of indoor crime scenes. Hematophagous mosquitoes were collected from two residential units; saliva of volunteers that were residents in the units was also collected for genetic analysis as reference samples. We examined the allele frequencies of 15 short tandem repeat loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA) and amelogenin. A total of 26 female hematophagous mosquitoes were identified as Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus; we were able to obtain 11 forensically valid genetic profiles, with a minimum of 0.028203 ng/μL of human DNA. Thus, the results of this study showed that it was possible to correlate human genetic information from mosquitoes with the volunteer reference samples, which validates the use of this information as forensic evidence. Furthermore, we observed mixed genetic profiles from one mosquito. Therefore, it is clearly important to collect these insects indoors where crimes were committed, because it may be possible to find intact genetic profiles of suspects in the blood found in the digestive tract of hematophagous mosquitoes for later comparison to identify an offender and/or exclude suspects

A B S T R A C TThe detection and identification of human body fluids at crime scenes is usually performed using colorimetric and crystallographic tests. However, these assays may limit the samples detection during the washing steps. Currently, biosensors are emerging as alternative devices in molecular biology, combining the specificity and sensitivity of biological systems with the computing power of microprocessors. Herein, we report a preliminary study of an electrochemical biosensor able to detect DNA sequences in solutions mixed with household cleaners, aiming to simulate the effects of these chemicals on sample detection. The device was made using pencil graphite, acting as a working electrode (PGE) and an Ag/AgCl pin as a reference electrode. Single-strand DNA probes (ssDNA) were immobilized on PGE surface and the hybridization assay was performed by immersing the ssDNA-PGE electrode in a buffer solution with the target sequence under specific annealing temperature for 10 min. Samples contamination was stimulated by household cleaners by immersing dsDNA-PGE immersed in solutions containing sodium hypochlorite, alcohol and SDS for 30 min. The current peaks obtained with ssDNA-PGE and dsDNA-PGE were highly distinguishable (118.6 nA and 24.435 nA, respectively), even when dsDNA-PGE was mixed with sodium hypochloride, alcohol and detergent (17.12 nA, 35.81 nA and 69.44 nA, respectively). These findings suggest that DNA biosensors have a great potential to be used as a confirmatory test to detect human body fluids in crime scenes.

Fragilidades na avaliação diagnóstica do hipotireoidismo congênito na triagem neonatal: Uma revisão integrativa de literatura Weaknesses in the diagnostic evaluation of congenital hypothyroidism in neonatal screening: An integrative literature review

Identification of perpetrators is crucial in criminal investigations, mainly in rape cases. Analysis of the area, victims' profile, as well as genotyping DNA markers from rapists may help to determine hotspots of the crime, in a way to prevent its recurrence. Herein, we report for the first time in Northeastern Brazil a preliminary genetic data analyses from rape cases that occurred in Pernambuco between 2012 and 2014. Moreover, the distribution of the cases, as well as a general profile of the victims were analyzed from official reports of Laboratório de Perícia e Pesquisa em Genética Forense (LPPGF-PE). The results showed that 62% of the cases are mainly located in the metropolitan area of Pernambuco. Eighty-eight percent of the victims were females and 37% were under age. Allele frequency was determined by at least 15 STRs and, in some cases, by Y-STRs and InDel markers. This study may contribute to the elucidation of rape crime investigation in the future.

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