Marcia Melo - Academia.edu (original) (raw)

Papers by Marcia Melo

ABSTRACT.- Alcântara M.D.B., Campos A.C., Melo M.A., Pereira Filho J.M., Nascimento E.R., Farias ... more ABSTRACT.- Alcântara M.D.B., Campos A.C., Melo M.A., Pereira Filho J.M., Nascimento E.R., Farias A.A., Sousa D.R.M. & Azevedo E.O. 2013. [Immune response in goats vaccinated against contagious agalactia.] Resposta imunológica em caprinos vacinados contra agalaxia contagiosa. Pesquisa Veterinária Brasileira 33(5):561-564. E-mail: edisio@pq.cnpq.br
This study aimed to evaluate the efficacy of two inactivated vaccines against contagious agalactia containing adjuvant oily and watery. For this, 73 goats were divided in two experiments.
In the experiment was verified the vaccine safety and 15 goats
were divided into three experimental groups of five animals each. A1 and B1 groups were immunized with vaccine containing either aluminum or oil, respectively, and group C was the control group
without immunization. In the experiment II, the immune response against the vaccines was evaluated by immunization of 58 goats that were divided in to two groups: group A2, 28 animals were immunized with the aluminum based vaccine; and group B2, 30 animals were immunized with the oil based vaccine. In the experiment II, the animals received a third dose on 180 day after the second dose. Antibody levels were determined by indirect
ELISA from ssamples collected on vaccination days and on 30 day after the second dose (Experiment I) and on 30 day after the third dose (Experiment II). The animals from B1 and B2 groups (oil based vaccine) demonstrated higher antibody levels (P<0.05) than A1 and A2 (aluminum based vaccine) in both experiments.
INDEX TERMS: Mycoplasma agalactiae, contagious agalactia, immunology, adjuvant, antibodies, vaccines, goats.

The available drugs for treatment of human visceral leishmaniasis do not frequently promote cure ... more The available drugs for treatment of human visceral leishmaniasis do not frequently promote cure of the dogs. Whereas new drugs are not available for use in dogs, it is necessary to test therapeutic trials using old drugs in association with other agents. The objective of this experiment was to test the therapeutic efficacy of the antimonial N-methyl glucamine in association with an antigenic extract of Leishmania braziliensis in asymptomatic
experimentally infected dogs. Thirty-two laboratory reared mongrel dogs were infected with 1x107 amastigotes of L. chagasi by via intravenous. During 450 days, the follow up was done by specific antibody detection, cellular immune response, and detection of the parasite in the bone marrow and other tissues. After the confirmation of the infection by antibody or parasite detection, the dogs were randomly allocated in four groups of eight animals each : Group A received antigen (500 µg/day) ; Group B received Glucantime® (100 mg/Kg/day) ; Group C received the antigen plus Glucantime® and group D received no treatment. All dogs were submitted to necropsy 450 days after inoculation. They were all infected. After the treatment, parasites were found in 50 % of the dogs from Group A, 14.2 % in the Group B, 42.8 % in the group C and 71.4 % in the Group D. Antibody levels dropped in B and C groups, but still detectable, not completely disappearing, remaining serologically positive during the whole period of observation.

Two immunoglobulin G enzyme-linked immunosorbent assay (ELISA) versions using whole promastigotes... more Two immunoglobulin G enzyme-linked immunosorbent assay (ELISA) versions using whole promastigotes of Leishmania infantum (syn. Leishmania chagasi) treated either with β-mercaptoethanol (β-ME-ELISA) or trypsin (TRYP-ELISA) as antigens were developed for the diagnosis of canine visceral leishmaniasis (CVL). By comparison with the direct agglutination test (DAT; 100%, 31/31; 95% confidence interval [CI]: 86.3-100%), slightly lower sensitivity was demonstrated for the newly developed β-ME-ELISA (93.5%, 29/31; 95% CI: 77.2-98.9%). Sensitivity was higher for β-ME-ELISA compared with TRYP-ELISA (87.1%, 27/31; 95% CI: 69.2-95.8%) in serum samples from dogs with CVL. When tested with sera from 37 healthy dogs and from 45 dogs with clinical conditions other than CVL, a specificity of 97.6% (80/82; 95% CI: 90.1-99.6%) was estimated for β-ME-ELISA as compared to 100% (82/82; 95% CI: 94.4-100%) and 95.1% (78/82; 95% CI: 87.3-98.4%) for DAT and TRYP-ELISA, respectively. Observed agreement was 94.0% (95% CI: 88.7-97.1%) between DAT and β-ME-ELISA (κ = 0.879; 95% CI: 0.803-0.956) and 87.4% (95% CI: 80.8-92.1%) between DAT and TRYP-ELISA (κ = 0.743; 95% CI: 0.636-0.851). Current results advocate application of the new β-ME-ELISA for diagnosis of CVL at the laboratory level and confirmation of results obtained with the DAT in field studies.

Ehrlichiosis and anaplasmosis are tick-borne diseases. Ehrlichia canis and Anaplasma platys infec... more Ehrlichiosis and anaplasmosis are tick-borne diseases. Ehrlichia canis and Anaplasma platys infect mainly white cells and platelets, respectively. The main DNA source for PCR is peripheral blood, but the potential of blood cell fractions has not been extensively investigated. This study aims at assessment of whole blood (WB) and blood fractions potential in nested PCR (nPCR) to diagnose canine ehrlichiosis and anaplasmosis. The 16S rRNA gene was amplified in 71.4, 17.8, 31.57, and 30% of the WB, granulocyte (G), mononuclear cells (M), and buffy coat (BC) samples. Compared to the WB, the sensitivity of the PCR was 42.86% for the M, and BC fractions, 21.43% for the G, and 33.33% for the blood clot (C). There was fair agreement between the WB and M, BC and C, and slight with the G. Fair agreement occurred between the nPCR and morulae in the blood smear. One animal was coinfected with A. platys and E. canis. This study provided the first evidence of A. platys infection in dogs in Paraíba, Brazil, and demonstrated that WB is a better DNA source than blood fractions to detect Ehrlichia and Anaplasma by nPCR, probably because of the plasma bacterial concentration following host cell lysis.

The objective of this paper was to report the isolation of two fluoroacetate degrading bacteria f... more The objective of this paper was to report the isolation of two fluoroacetate degrading bacteria from the rumen of goats. The animals were adult goats, males, crossbred, with rumen fistula, fed with hay, and native pasture. The rumen fluid was obtained through the rumen fistula and immediately was inoculated 100μL in mineral medium added with 20mmolL−1 sodium fluoroacetate (SF), incubated at 39°C in an orbital shaker. Pseudomonas fluorescens (strain DSM 8341) was used as positive control for fluoroacetate dehalogenase activity. Two isolates were identified by 16SrRNA gene sequencing as Pigmentiphaga kullae (ECPB08) and Ancylobacter dichloromethanicus (ECPB09). These bacteria degraded sodium fluoroacetate, releasing 20mmolL−1 of fluoride ion after 32 hours of incubation in Brunner medium containing 20mmolL−1 of SF. There are no previous reports of fluoroacetate dehalogenase activity for P. kullae and A. dichloromethanicus. Control measures to prevent plant intoxication, including use of fences, herbicides, or other methods of eliminating poisonous plants, have been unsuccessful to avoid poisoning by fluoroacetate containing plants in Brazil. In this way, P. kullae and A. dichloromethanicus may be used to colonize the rumen of susceptible animals to avoid intoxication by fluoroacetate containing plants.

The aim of this work was to isolate and identify bacteria able to degrade sodium ﬂuoroacetate fro... more The aim of this work was to isolate and identify bacteria able to degrade sodium ﬂuoroacetate from soil and plant samples collected in areas where the ﬂuoroacetate-containing plants Mascagnia rigida and Palicourea aenofusca are found. The samples were cultivated in mineral medium added with 20 mmol L
−1 sodium ﬂuoroacetate. Seven isolates were identiﬁed by 16S rRNA gene sequencing as Paenibacillus sp. (ECPB01), Burkholderia sp. (ECPB02), Cupriavidus sp. (ECPB03), Staphylococcus sp. (ECPB04), Ancylobacter sp. (ECPB05), Ralstonia sp. (ECPB06), and Stenotrophomonas sp. (ECPB07). All seven isolates degraded sodium-ﬂuoroacetate-containing in the medium, reaching deﬂuorination rate of ﬂuoride ion of 20 mmol L
−1. Six of them are reported for the ﬁrst time as able to degrade sodium ﬂuoroacetate (SF). In the future, some of these microorganisms can be used to establish in the rumen an engineered bacterial population able to degrade sodium ﬂuoroacetate and protect ruminants from the poisoning by
this compound.