Leishmania spp. diagnosis and therapeutic management in a cat from urban area in Ibagué (Colombia).

BACKGROUND: Leishmania spp., a protozoan transmitted by sandflies, widely affects humans and dogs in Colombia, nevertheless feline leishmaniasis (FeL) remains understudied. OBJECTIVE: This study reports a case of feline leishmaniasis in Colombia and its therapeutic management. METHODS: Complete blood count, renal and hepatic serum biochemistry, nodular lesion cytology, FeLV/FIV snap test, abdominal ultrasound, and molecular diagnosis of Leishmania spp. 16 s rRNA gene amplification by real-time-PCR (qPCR), ITS-1 and hsp70 gene by endpoint-PCR and Sanger sequencing were performed. RESULTS: The patient was negative for FIV/FeLV and showed leukocytosis, lymphocytosis, thrombocytopenia, neutrophilia, monocytosis, hypergammaglobulinemia, increased gamma-glutamyl-transferase, cortical nephrocalcinosis, diffuse heterogeneous splenic parenchyma, and cholangitis. Nodular lesion cytology, qPCR and Sanger sequencing confirmed the diagnosis of Leishmania spp. The patient was treated with allopurinol and miltefosine. After treatment, clinical signs disappeared. CONCLUSION: Clinical examination, cytology, and molecular tests allowed a rapid and sensitive FeL diagnosis. Allopurinol and miltefosine improved the clinical condition of the cat.

Current developments of SELEX technologies and prospects in the aptamer selection with clinical applications.

Aptamers are single-stranded oligonucleotide sequences capable of binding to specific ligands with high affinity. In this manner, they are like antibodies but have advantages such as lower manufacturing costs, lower immunogenicity, fewer batch-to-batch differences, a longer shelf life, high tolerance to different molecular milieus, and a greater number of potential targets. Due to their special features, they have been used in drug delivery, biosensor technology, therapy, and diagnostics. The methodology that allowed its production was the "Systematic Evolution of Ligands by Exponential enrichment" (SELEX). Unfortunately, the traditional protocol is time-consuming and laborious. Therefore, numerous variants with considerable optimization steps have been developed, nonetheless, there are still challenges to achieving real applications in the clinical field. Among them, are control of in vivo activities, fast renal filtration, degradation by nucleases and toxicity testing. This review focuses on current technologies based on SELEX, the critical factors for successful aptamer selection, and its upcoming biomedical and biotechnological applications.

Virulence genes identification in Salmonella enterica isolates from humans, crocodiles, and poultry farms from two regions in Colombia.

Background and Aim: Salmonella spp. is frequently found in the digestive tract of birds and reptiles and transmitted to humans through food. Salmonellosis is a public health problem because of pathogenicity variability in strains for virulence factors. This study aimed to identify the virulence genes in Salmonella isolates from humans, crocodiles, broiler cloacas, and broiler carcasses from two departments of Colombia. Materials and Methods: This study was conducted on 31 Salmonella enterica strains from humans with gastroenteritis (seven), crocodiles (seven), broiler cloacas (six), and broiler carcasses (12) from Tolima and Santander departments of Colombia, belonging to 21 serotypes. All samples were tested for Salmonella spp. using culture method on selective and non-selective mediums. Extraction of genomic DNA was performed from fresh colonies, DNA quality was verified by spectrophotometry and confirmed by amplification of InvA gene using conventional polymerase chain reaction (PCR). bapA, fimA, icmF, IroB, marT, mgtC, nlpI, oafA, pagN, siiD, spvC, spvR, spvB, Stn, and vexA genes were amplified by PCR. Results: The most prevalent gene was bapA (100%), followed by marT (96.77%), mgtC (93.55%), and fimA (83.87%). Likewise, IroB (70.97%), Stn (67.74%), spvR (61.29%), pagN (54.84%), icmF (54.8%), and SiiD (45.16%) were positive for more than 50% of the strains. Furthermore, none of the isolates tested positive for the vexA gene. Salmonella isolates presented 26 virulence profiles. Conclusion: This study reported 14 virulence genes in Salmonella spp. isolates from humans with gastroenteritis, crocodiles, and broiler cloacas and carcasses. The distribution of virulence genes differed among sources. This study could help in decision-making by health and sanitary authorities.

First study on microscopic and molecular detection of Acanthocheilonema reconditum and Leishmania infantum coinfection in dogs in Southwest Colombia.

Background and Aim: Canine vector-borne diseases represent an important issue for the welfare and health of animals, but also have great zoonotic potential. These diseases are caused by bacteria, nematodes such as filariae, and other parasites such as Leishmania spp. Given the difficulty in differentiating common microfilariae in dogs by microscopy and serological methods, molecular techniques such as polymerase chain reaction (PCR) and sequencing should be valuable for reaching a reliable diagnosis. This study aimed to use microscopy and PCR to identify the microfilarial species in dogs from Valle del Cauca, Colombia, and a possible association with Leishmania infantum parasites. Materials and Methods: This study was conducted on 270 dogs from Pradera and Florida municipalities. Microfilariae were detected in dogs by optical microscopy and amplification with 5.8S-ITS2-28S. Species identification was achieved through the amplification of the gene cytochrome oxidase I (COX1). Results: Microscopic detection of microfilariae was possible in 4.81% (13/270) of the dogs. In addition, by PCR of COX1 and Sanger sequencing of ITS2, Acanthocheilonema reconditum was identified as the circulating microfilarial species in 12 dogs, coinfecting with the species L. infantum (Leishmania donovani complex). Conclusion: To the best of our knowledge, this is the first report on A. reconditum and L. infantum mixed infection in dogs in Colombia, particularly in the Valle del Cauca.

Molecular characterization of HEPCIDIN-1 (HAMP1) gene in red-bellied pacu (Piaractus brachypomus).

Hepcidins are cysteine-rich peptides, which participate in iron metabolism regulation, the inflammatory and antimicrobial response. This study characterizes the hepcidin-1 (HAMP1) gene, its transcript expression in different tissues, as well as its regulation in a model of brain injury in Piaractus brachypomus. Bioinformatic analysis was carried out to determine conserved domains, glycosylation sites and protein structure of HAMP1, and probability that HAMP1 corresponds to an antimicrobial peptide (AMP). Relative gene expression of the P. brachypomus HAMP1 gene was determined by qPCR from cDNA of several tissues, a brain injury model, an organophosphate sublethal toxicity model and anesthetic experiment using the 2-ΔΔCt method. HAMP1 ORF encodes for a 91 aa pre-prohepcidin conformed for a prodomain with 42 aa and mature peptide of 25 aa. Mature domain was determined as an AMP. HAMP1 transcript is expressed in all the tissues, being higher in the spleen and liver. HAMP1 mRNA level was upregulated in the brain injury group, as well as in the olfactory bulb, optic chiasm and telencephalon of red-bellied pacu brain exposed to an organophosphate. In anesthetic experiment, HAMP1 mRNA level was upregulated in the liver and gills. HAMP1 gene of P. brachypomus may be involved in the inflammatory, antimicrobial, hypoxia and stress oxidative response.

High prevalence of Leishmania spp. in dogs from Central West Colombia.

Leishmaniasis is a widespread disease caused by species of the genus Leishmania. In Colombia, this zoonosis is endemic in rural areas with a high prevalence in the departments of Antioquia, Santander, Meta, Tolima and Nariño. Dogs are the most important domestic reservoirs of the pathogen, given the epidemiological importance of dogs in the control of leishmaniasis is needed to determine the prevalence of Leishmania spp. in canine population of the rural area of Ibagué and to identify potential risk factors related to the presence of this parasite. A cross-sectional study was carried out in 173 dogs from the rural area of Ibagué. Leishmania spp. was detected by amplifying the Internal Transcribed Spacer (ITS-1) and two regions of the hsp70 gene through PCR. Factor associations were calculated through the Chisquare and odds ratio. Prevalence of Leishmania spp. infection in dogs was of 91.33% (158/173), where 36.71% (58/158) of the Leishmania spp. positive dogs showed one or more clinical signs of canine leishmaniasis and 63.29% (100/158) of the dogs were asymptomatic. Factors associated with the presence of the parasite did not show significance. In addition, hsp70D-PCR was proved to be highly efficient for the detection of Leishmania spp.