Foot-and-mouth disease virus: DNA aptamer selection for the 3ABC protein.

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.

DNA aptamers selection for Staphylococcus aureus cells by SELEX and Cell-SELEX.

Background: 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.

DNA aptamer selection and construction of an aptasensor based on graphene FETs for Zika virus NS1 protein detection.

Zika virus (ZIKV) is a mosquito-borne virus that is phylogenetically close to other medically important flaviviruses with high global public health significance, such as dengue (DENV) and yellow fever (YFV) viruses. Correct diagnosis of a flavivirus infection can be challenging, particularly in world regions where more than one flavivirus co-circulates and YFV vaccination is mandatory. Acid nucleic aptamers are oligonucleotides that bind to a specific target molecule with high affinity and specificity.

Evaluation of the specific uptake of radiolabeled Staphylococcus aureus aptamers in the infectious foci.

The 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.

Real-time PCR for direct aptamer quantification on functionalized graphene surfaces.

In this study, we develop a real-time PCR strategy to directly detect and quantify DNA aptamers on functionalized graphene surfaces using a Staphylococcus aureus aptamer (SA20) as demonstration case. We show that real-time PCR allowed aptamer quantification in the range of 0.05 fg to 2.

A carefully designed nanoplatform based on multi walled carbon nanotube wrapped with aptamers.

The interaction between carbon nanotubes (CNTs) and biological molecules of diagnostic and therapeutic interest, as well as the internalization of the CNTs-biomolecules complexes in different types of cell, has been extensively studied due to the potential use of these nanocomplexes as multifunctional nanoplatforms in a great variety of biomedical applications. The effective use of these nanobiotechnologies requires broad multidisciplinary studies of biocompatibility, regarding, for example, the in vitro and in vivo nanotoxicological assays, the capacity to target specific cells and the evaluation of their biomedical potential. However, the first step to be reached is the careful obtainment of the nanoplatform and the understanding of the actual surface composition and structural integrity of the complex system.

Detection of bacterial infection by a technetium-99m-labeled peptidoglycan aptamer.

Nuclear 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.

Scintigraphic imaging of Staphylococcus aureus infection using Tc radiolabeled aptamers.

Staphylococcus 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.

Mouse Immunization with Radioattenuated Yeast Cells of Paracoccidioides brasiliensis.

Paracoccidioides 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.

High Efficiency Binding Aptamers for a Wide Range of Bacterial Sepsis Agents.

Sepsis is a major health problem worldwide, with an extremely high rate of morbidity and mortality, partly due to delayed diagnosis during early disease. Currently, sepsis diagnosis requires bacterial culturing of blood samples over several days, whereas PCR-based molecular diagnosis methods are faster but lack sensitivity. The use of biosensors containing nucleic acid aptamers that bind targets with high affinity and specificity could accelerate sepsis diagnosis.

(1→3)-β-D-glucan aptamers labeled with technetium-99m: Biodistribution and imaging in experimental models of bacterial and fungal infection.

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.

Evaluation of conjunctival swab as a mass-screening tool for molecular diagnosis of canine visceral leishmaniasis.

The 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.

Identification of Staphylococcus aureus infection by aptamers directly radiolabeled with technetium-99m.

Introduction: 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.

Selection of peptidoglycan-specific aptamers for bacterial cells identification.

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.

Aptamers directly radiolabeled with technetium-99m as a potential agent capable of identifying carcinoembryonic antigen (CEA) in tumor cells T84.

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.

Detection of Leishmania infantum in 4 different dog samples by real-time PCR and ITS-1 nested PCR.

The 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.

Nasal, oral and ear swabs for canine visceral leishmaniasis diagnosis: new practical approaches for detection of Leishmania infantum DNA.

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.

Canine skin and conjunctival swab samples for the detection and quantification of Leishmania infantum DNA in an endemic urban area in Brazil.

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.

The use of conjunctival swab samples for PCR screening for visceral leishmaniasis in vaccinated dogs.

The polymerase chain reaction (PCR) has been shown to provide a rapid and sensitive technique for Leishmania detection. The aim of this study was to evaluate the technique of noninvasive conjunctival swabs (CS) as a sampling method for molecular screening for visceral leishmaniasis (VL) in a group of 42 police dogs, all of them vaccinated against VL, and to compare the results with those obtained by serological tests. The serological assays were performed independently by three laboratories.

Gamma radiation effects on Sporothrix schenckii yeast cells.

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.

The molecular detection of different Leishmania species within sand flies from a cutaneous and visceral leishmaniasis sympatric area in Southeastern Brazil.

Over the last 20 years, there has been an increase in the number of leishmaniasis cases in Brazil. Belo Horizonte (BH) is one of the most highly populated Brazilian cities that is affected by visceral leishmaniasis (VL). The health services in BH are coordinated by a central nucleus that is subdivided into nine sanitary districts.

PCR diagnosis of visceral leishmaniasis in asymptomatic dogs using conjunctival swab samples.

The 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.

Inaccuracy of enzyme-linked immunosorbent assay using soluble and recombinant antigens to detect asymptomatic infection by Leishmania infantum.

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).

Mice immunization with radioattenuated yeast cells of Paracoccidiodes brasiliensis: influence of the number of immunizations.

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.