Foot-and-mouth disease (FMD) is a devastating livestock disease caused by foot-and-mouth disease virus (FMDV), a member of the Picornaviridae family. The 3ABC is a non-structural protein of FMDV, produced during viral replication and absent from inactivated FMD vaccines. Nucleic acid aptamers are DNA or RNA oligonucleotides capable of binding with high specificity and affinity to a molecular target.
View Article and Find Full Text PDFBackground: Staphylococcus aureus is the most common bacteria found in skin, soft tissues, bone, and bone prostheses infections. The aim of this study was to select DNA aptamers for S. aureus to be applied in the diagnosis of bacteria.
View Article and Find Full Text PDFThe specific uptake of Tc radiolabeled Staphylococcus aureus aptamers in the infectious foci was evaluated by scintigraphic imaging of infection-bearing mice. The radiotracer uptake was inhibited by non-radiolabeled aptamers in a competition assay. In addition, when a different number of bacterial cells was used to infect mice an increase in the target/non-target ratios of images correlated with the increase of CFU per gram of tissue was verified.
View Article and Find Full Text PDFNuclear medicine clinicians are still waiting for the optimal scintigraphic imaging agents capable of distinguishing between infection and inflammation, and between fungal and bacterial infections. Aptamers have several properties that make them suitable for molecular imaging. In the present study, a peptidoglycan aptamer (Antibac1) was labeled with Tc and evaluated by biodistribution studies and scintigraphic imaging in infection-bearing mice.
View Article and Find Full Text PDFStaphylococcus aureus is a specie of great medical importance associated with many infections as bacteremia and infective endocarditis as well as osteoarticular, skin and soft tissue, pleuropulmonary, and device related infections. Early identification of infectious foci is crucial for successful treatment. Scintigraphy could contribute to this purpose since specific radiotracers were available.
View Article and Find Full Text PDFParacoccidioides brasiliensis is the agent of paracoccidioidomycosis, the most prevalent mycosis in Latin America, and currently there is no effective vaccine. The present chapter describes the methodology to obtain radioattenuated yeast cells of P. brasiliensis and a protocol to evaluate protective response elicited by this immunogen in experimental paracoccidioidomycosis.
View Article and Find Full Text PDFNucl Med Biol
March 2017
Introduction: Acid nucleic aptamers are RNA or DNA oligonucleotides capable of binding to a target molecule with high affinity and selectivity. These molecules are promising tools in nuclear medicine. Many aptamers have been used as targeting molecule of radiopharmaceuticals in preclinical studies.
View Article and Find Full Text PDFThe canine visceral leishmaniasis (CVL) diagnosis is an important step of visceral leishmaniasis control program in Brazil once the dog is the main reservoir host of the disease. The aim of this study was to evaluate the conjunctival swab (CS) as a mass-screening tool for CVL molecular diagnosis in an endemic area classified as priority for the Brazilian Ministry of Healthy for surveillance action. A total of 1350 domiciled dogs were screened.
View Article and Find Full Text PDFIntroduction: Aptamers are oligonucleotides that have high affinity and specificity for their molecular targets which are emerging as a new class of molecules for radiopharmaceuticals development. In this study, aptamers selected to Staphylococcus aureus were evaluated for bacterial infection identification.
Methods: Anti S.
Peptidoglycan is a highly complex and essential macromolecule of bacterial outer cell wall; it is a heteropolymer made up of linear glycan strands cross-linked by peptides. Peptidoglycan has a particular composition which makes it a possible target for specific bacterial recognition. Aptamers are single-stranded DNA or RNA oligonucleotides that bind to target molecules with high affinity and specificity.
View Article and Find Full Text PDFBioorg Med Chem Lett
April 2014
Aptamers are small oligonucleotides that are selected to bind with high affinity and specificity to a target molecule. Aptamers are emerging as a new class of molecules for radiopharmaceutical development. In this study a new method to radiolabel aptamers with technetium-99m ((99m)Tc) was developed.
View Article and Find Full Text PDFThe canine visceral leishmaniasis (CVL) diagnosis is an important step of visceral leishmaniasis control program in Brazil, which involves the elimination of infected dogs, the main animal reservoir host of the disease. The aim of the present study was to evaluate a sensitive real-time PCR method for Leishmania infantum detection in 4 different clinical samples of dogs, including the noninvasive conjunctival swab (CS) sample. The results of real-time PCR were compared with those obtained using internal transcribed spacer 1 nested PCR.
View Article and Find Full Text PDFPLoS Negl Trop Dis
November 2013
Background: The aim of this study was to evaluate the potential use of nasal, oral, and ear swabs for molecular diagnosis of canine visceral leishmaniasis (CVL) in an endemic urban area in Brazil.
Methodology/principal Findings: Sixty-two naturally infected and ten healthy dogs were enrolled in this study. Bone marrow aspirates, peripheral blood, skin biopsy, and conjunctival, nasal, oral, and ear swabs were collected.
PLoS Negl Trop Dis
August 2012
Background: We evaluated kDNA PCR/hybridization and quantitative real-time PCR (qPCR) targeting the gene of DNA polymerase of Leishmania infantum for CVL diagnosis and assessment of parasite load in clinical samples obtained invasively and non-invasively.
Methodology/principal Findings: Eighty naturally infected dogs from an endemic urban area in Brazil were used. Animals were divided into two groups based on the presence or absence of CVL clinical sings.
Sporotrichosis is a subcutaneous mycosis caused by Sporothrix schenckii. Zoonotic transmission to man can occur after scratches or bites of animals, mainly cats. In this study, the gamma radiation effects on yeast of S.
View Article and Find Full Text PDFThe efficacy of conjunctival swab (CS) as a sampling method for visceral leishmaniasis (VL) diagnosis by PCR of asymptomatic dogs was evaluated. The CS was compared to blood samples (B) and skin biopsies (SB), two less invasive samples potentially useful for massive screening of dogs. Thirty asymptomatic dogs, with serological and parasitological positive tests, were used.
View Article and Find Full Text PDFPLoS Negl Trop Dis
October 2009
Background: One of the most important drawbacks in visceral leishmaniasis (VL) population studies is the difficulty of diagnosing asymptomatic carriers. The aim of this study, conducted in an urban area in the Southeast of Brazil, was to evaluate the performance of serology to identify asymptomatic VL infection in participants selected from a cohort with a two-year follow-up period.
Methodology: Blood samples were collected in 2001 from 136 cohort participants (97 positive and 39 negatives, PCR/hybridization carried out in 1999).
Paracoccidioides brasiliensis is the agent of paracoccidioidomycosis, the most prevalent mycosis in Latin America. Up to the moment no vaccine has been reported. The aim of this study was to evaluate the influence of the number of immunizations on the protection elicited by radioattenuated yeast cells of P.
View Article and Find Full Text PDFFour PCR assays for detection of Leishmania DNA in conjunctival swab samples were compared. All methods had two steps: a first amplification followed by hybridization or by a new amplification (nested or seminested). Two methods (kDNA PCR-hybridization and kDNA snPCR) used primers targeted to the minicircles of kinetoplast DNA (kDNA) and the other two methods to the coding (LnPCR) and intergenic noncoding regions (ITS-1 nPCR) of ribosomal rRNA genes.
View Article and Find Full Text PDFThe visceral leishmaniasis (VL) in Brazil is caused by Leishmania chagasi (L. infantum) and dogs are considered to be the main domestic reservoir. The epidemiological control involves the elimination of infected dogs.
View Article and Find Full Text PDFVaccine
November 2007
Paracoccidioides brasiliensis is the fungus agent of paracoccidioidomycosis, a chronic systemic disease prevalent in Latin America. The aim of the present work was to evaluate the protection elicited by the immunization of BALB/c mice with radioattenuated yeast cells of P. brasiliensis.
View Article and Find Full Text PDFParacoccidioides brasiliensis is a thermally dimorphic fungus agent of paracoccidioidomycosis, a deep-seated systemic infection of humans with high prevalence in Latin America. Until now no vaccine has been reported. Ionizing radiation can be used to attenuate pathogens for vaccine development and we have successfully attenuated yeast cells of P.
View Article and Find Full Text PDFParacoccidioides brasiliensis is the agent of paracoccidioidomycosis, the most prevalent mycosis in Latin America, and currently there is no effective vaccine. The aim of this study was to attenuate the yeast form of P. brasiliensis by gamma irradiation for further studies on vaccine research.
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