Magnetic Seed vs Guidewire Breast Cancer Localization With Magnetic Lymph Node Detection: A Randomized Clinical Trial.

Importance: Guidewires have been the standard for breast lesion localization but pose operative and logistic challenges. Paramagnetic seeds have shown promising results, but to the authors' knowledge, no randomized comparison has been performed. Objective: To determine whether the combination of a paramagnetic seed and superparamagnetic iron oxide (SPIO) is equivalent to guidewire and SPIO for breast cancer localization and sentinel lymph node detection (SLND). Design, Setting, and Participants: This was a phase 3, pragmatic, equivalence, 2-arm, open-label, randomized clinical trial conducted at 3 university and/or community hospitals in Sweden from May 2018 to May 2022. Included in the study were patients with early breast cancer planned for breast conservation and SLND. Study data were analyzed July to November 2022. Interventions: Participants were randomly assigned 1:1 to a paramagnetic seed or a guidewire. All patients underwent SLND with SPIO. Main Outcomes and Measures: Re-excision rate and resection ratio (defined as actual resection volume / optimal resection volume). Results: A total of 426 women (median [IQR] age, 65 [56-71] years; median [IQR] tumor size, 11 [8-15] mm) were included in the study. The re-excision rate was 2.90% (95% CI, 1.60%-4.80%), and the median (IQR) resection ratio was 1.96 (1.15-3.44). No differences were found between the guidewire and the seed in re-excisions (6 of 211 [2.84%] vs 6 of 209 [2.87%]; difference, -0.03%; 95% CI, -3.20% to 3.20%; P = .99) or resection ratio (median, 1.93; IQR, 1.18-3.43 vs median, 2.01; IQR, 1.11-3.47; P = .70). Overall SLN detection was 98.6% (95% CI, 97.1%-99.4%) with no differences between arms (203 of 207 [98.1%] vs 204 of 206 [99.0%]; difference, -0.9%; 95% CI, -3.6% to 1.8%; P = .72). More failed localizations occurred with the guidewire (21 of 208 [10.1%] vs 4 of 215 [1.9%]; difference, 8.2%; 95% CI, 3.3%-13.2%; P < .001). Median (IQR) time to specimen excision was shorter for the seed (15 [10-22] minutes vs 18 [12-30] minutes; P = .01), as was the total operative time (69 [56-86] minutes vs 75.5 [59-101] minutes; P = .03). The experience of surgeons, radiologists, and surgical coordinators was better with the seed. Conclusions and Relevance: The combination of SPIO and a paramagnetic seed performed comparably with SPIO and guidewire for breast cancer conserving surgery and resulted in more successful localizations, shorter operative times, and better experience. Trial Registration: ISRCTN.org Identifier: ISRCTN11914537.

Evaluation of tumor-infiltrating lymphocytes and mammographic density as predictors of response to neoadjuvant systemic therapy in breast cancer.

BACKGROUND: Response rates vary among breast cancer patients treated with neoadjuvant systemic therapy (NAST). Thus, there is a need for reliable treatment predictors. Evidence suggests tumor-infiltrating lymphocytes (TILs) predict NAST response. Still, TILs are seldom used clinically as a treatment determinant. Mammographic density (MD) is another potential marker for NAST benefit and its relationship with TILs is unknown. Our aims were to investigate TILs and MD as predictors of NAST response and to study the unexplored relationship between TILs and MD. MATERIAL AND METHODS: We studied 315 invasive breast carcinomas treated with NAST between 2013 and 2020. Clinicopathological data were retrieved from medical records. The endpoint was defined as pathological complete response (pCR) in the breast. TILs were evaluated in pre-treatment core biopsies and categorized as high (≥10%) or low (<10%). MD was scored (a-d) according to the breast imaging reporting and data system (BI-RADS) fifth edition. Binary logistic regression and Spearman's test of correlation were performed using SPSS. RESULTS: Out of 315 carcinomas, 136 achieved pCR. 94 carcinomas had high TILs and 215 had low TILs. Six carcinomas had no available TIL data. The number of carcinomas in each BI-RADS category were 37, 122, 112, and 44 for a, b, c, and d, respectively. High TILs were independently associated with pCR (OR: 2.95; 95% CI: 1.59-5.46) compared to low TILs. In the univariable analysis, MD (BI-RADS d vs. a) showed a tendency of higher likelihood for pCR (OR: 2.43; 95% CI: 0.99-5.98). However, the association was non-significant, which is consistent with the result of the multivariable analysis (OR: 2.51; 95% CI: 0.78-8.04). We found no correlation between TILs and MD (0.02; p = .80). CONCLUSION: TILs significantly predicted NAST response. We could not define MD as a significant predictor of NAST response. These findings should be further replicated.

Novel Phenothiazine-Bridged Porphyrin-(Hetero)aryl dyads: Synthesis, Optical Properties, In Vitro Cytotoxicity and Staining of Human Ovarian Tumor Cell Lines.

We report here the synthetic procedure applied for the preparation of new AB3-type and trans-A2B2 type meso-halogenophenothiazinyl-phenyl-porphyrin derivatives, their metal core complexation and their peripheral modification using Suzuki-Miyaura cross coupling reactions with various (hetero)aryl (phenothiazinyl, 7-formyl-phenothiazinyl, (9-carbazolyl)-phenyl and 4-formyl-phenyl, phenyl) boronic acid derivatives. The meso-phenothiazinyl-phenyl-porphyrin (MPP) dyes family was thus extended by a series of novel phenothiazine-bridged porphyrin-(hetero)aryl dyads characterized by UV-Vis absorption/emission properties typical to the porphyrin chromophore, slightly modulated by increasing the size of peripheral substituents. Three phenothiazine-bridged porphyrin-heteroaryl dyads with fluorescence emission above 655 nm were selected as fluorophores in red spectral region for applications in cellular staining of human ovarian tumors. In vitro experiments of cell metabolic activity displayed a moderate toxicity on human ovarian tumor cell lines (OVCAR-3, cisplatin-sensitive A2780 and cisplatin-resistant A2780cis respectively). Visualization of the stained living cells was performed both by fluorescence microscopy imaging and by fluorescence lifetime imaging under two photon excitation (TPE-FLIM), confirming their cellular uptake and the capability of staining the cell nucleus.

Comparison of Quality of Life and Learning Success of Adolescents Surviving Cancer and Their Classmates.

The aim of this study was to compare the quality of life and school success of adolescent survivors and their classmates. A survey was conducted among 21 cancer survived 12-18-year-old children and 95 of their classmates by using questionnaires covering (a) characteristics of the quality of life; (b) characteristics of the learning process; and (c) level of the fear of cancer recurrence. Significant difference was found in the field of physical and emotional functions but contrary to expected, the members of the control group reported lower values than survivor children. Those children that were teased because of cancer made friends hardly and got involved in social programs with more difficulty. With reference to the level of development of school motivation and the use of learning strategies, it was experienced a significant difference between the two groups only in the field of planning. Our results show that the better the survived children's general quality of life is the better results they achieve at school. Their learning achievement is influenced to a much bigger extent by social functions than their physical disadvantages.

Correlation Analysis of Potential Breast Cancer Resistance Protein Probes in Different Monolayer Systems.

Breast cancer resistance protein (BCRP) is a point of interest in drug-drug interaction safety testing. Therefore, a consensus probe that can be applied as victim in multiple experimental settings is of great benefit. Identification of candidates has been driven by the amount and quality of available clinical data, and as a result, drugs such as sulfasalazine and rosuvastatin have been suggested. In this article, the in vitro performance of 5 possible alternatives was evaluated: atorvastatin, chlorothiazide, dantrolene, topotecan, and teriflunomide, and benchmarked against sulfasalazine and rosuvastatin in reference in vitro assays for BCRP drug-drug interaction testing. Based on the results, teriflunomide is proposed as an alternate in vitro BCRP probe.

Abcb1a (P-glycoprotein) limits brain exposure of the anticancer drug candidate seliciclib in vivo in adult mice.

Seliciclib displayed limited brain exposure in vivo in adult rats with mature blood-brain barrier (BBB). Selicilib was shown to be a specific substrate of human ABCB1 in vitro. To demonstrate that ABCB1/Abcb1 can limit brain exposure in vivo in mice we are showing that seliciclib is a substrate of mouse Abcb1a, the murine ABCB1 ortholog expressed in the BBB as LLC-PK-Abcb1a cells displayed an efflux ratio (ER) of 15.31±3.54 versus an ER of 1.44±0.10 in LLC-PK1-mock cells. Additionally, in the presence of LY335979, an ABCB1/Abcb1a specific inhibitor, the observed ER for seliciclib in the LLC-PK1-mMdr1a cells decreased to 1.05±0.25. To demonstrate in vivo relevance of seliciclib transport by Abcb1a mouse brain microdialysis experiments were carried out that showed that the AUCbrain/AUCblood ratio of 0.143 in anesthetized mice increased about two-fold to 0.279 in the presence of PSC833 another ABCB1/Abcb1a specific inhibitor. PSC833 also increased the brain exposure (AUCbrain) of seliciclib close to 2-fold (136 vs 242) in awake mice. In sum, Abcb1a significantly decreases seliciclib permeability in vitro and is partly responsible for limited brain exposure of seliciclib in vivo in mice.

Species specificity profiling of rat and human organic cation/carnitine transporter Slc22a5/SLC22A5 (Octn2/OCTN2).

The purpose of this study was to characterize the uptake of carnitine, the physiological substrate, and the uptake of 3-(2,2,2-trimethylhydrazinium)propionate, a consensus substrate by rat Octn2 and human OCTN2 transporters as well as to characterize drug-mediated inhibition of l-carnitine uptake by the rat and human orthologs overexpressed in CHO-K1 cells. l-carnitine and 3-(2,2,2-trimethylhydrazinium)propionate were found to be a lower affinity substrate for rat Octn2 (KM = 32.66 ± 5.11 µM and 23.62 ± 4.99 µM respectively) than for human OCTN2 (KM = 3.08 ± 0.74 µM and 7.98 ± 0.63 µM). The intrinsic clearance (CLint) value for carnitine was higher for the human than for the rat transporter (22.82 ± 5.57 ml/min*mg vs 4.008 ± 0.675 ml/min*mg). For 3-(2,2,2-trimethylhydrazinium)propionate, in contrast, the CLint value for rat Octn2 was higher than for human OCTN2 (323.9 ± 72.8 ml/min*mg vs 65.11 ± 5.33 ml/min*mg). Furthermore, many pharmacologically important drugs were shown to affect l-carnitine transport by Octn2/OCTN2. The correlation between the IC50 datasets for the rat and human transporter resulted in an r value of 0.47 (p > 0.05). However, the greatest difference was less than seven-fold and 13 of 15 compounds yielded a difference less than 3-fold. Thus, the transporters from these two species showed an overlapping but somewhat different substrate and inhibitor specificity.

Regulation of plasma factor XIII levels in healthy individuals; a major impact by subunit B intron K c.1952+144 C>G polymorphism.

BACKGROUND: The regulation of plasma factor XIII (FXIII) levels in healthy individuals has been only partially explored. The identification of major non-genetic and genetic regulatory factors might provide important information on the contribution of FXIII to the risk of cardio/cerebrovascular diseases. OBJECTIVES: To determine the effect of age, smoking, BMI, fibrinogen concentration on plasma FXIII activity, complex FXIII antigen (FXIII-A2B2) and total FXIII-B subunit (tFXIII-B) level, to correlate FXIII-B level with the other two FXIII parameters and to assess the variation of FXIII levels in carriers of major FXIII subunit polymorphisms. METHODS: 268 healthy individuals were enrolled in the study. FXIII activity was measured by the ammonia release assay; FXIII-A2B2 and tFXIII-B were determined by ELISAs. FXIII-A p.Val34Leu, FXIII-B p.His95Arg and FXIII-B intron K c.1952+144 C>G polymorphisms were identified by RT-PCR using melting point analysis with fluorescence resonance energy transfer detection. RESULTS: All investigated FXIII parameters showed significant positive correlation with age and fibrinogen level; gender and BMI influenced only tFXIII-B. A highly significant positive correlation was demonstrated between tFXIII-B and the other FXIII parameters. FXIII-A p.Val34Leu polymorphism had only slight, if any effect on FXIII levels. The FXIII-B Arg95 allele moderately increased all three FXIII parameters, but the effect became statistically significant only after adjustment. The FXIII-B intron K G allele drastically decreased FXIII levels, and it seemed to be in synergism with the FXIII-A Leu34 allele. CONCLUSIONS: Plasma FXIII levels are subjected to multifactorial regulation, in which age, fibrinogen level and FXIII-B intron K polymorphism are major determinants.

Kinetic characterization of sulfasalazine transport by human ATP-binding cassette G2.

The pharmacokinetics of sulfasalazine, an anti-inflammatory drug is influenced by ATP-binding cassette G2 (ABCG2) (breast cancer resistance protein (BCRP), mitoxantrone resistance protein (MXR)) both in vitro and clinically. Due to its low passive permeability, the intracellular concentration of sulfasalazine is dependent on uptake transporters, rendering the characterization of transporter specific interactions in cell based experimental systems difficult. Applying membrane assays a detailed kinetic analysis of sulfasalazine ABCG2 interaction was conducted and Km values of 0.70 +/- 0.03 microM and 0.66 +/- 0.08 microM were obtained at pH 7.0 and pH 5.5, respectively.

P-glycoprotein inhibition by membrane cholesterol modulation.

P-glycoprotein (Pgp) is a transmembrane protein that actively exports lipophilic chemotherapeutics from the cells causing multidrug resistance. Pgp molecules are partially localized in TX-100-resistant rafts, and the activity of the transporter is highly sensitive to the presence of cholesterol. To better understand these relationships, the influence of membrane cholesterol content on Pgp function, as measured via calcein accumulation, was studied in correlation with changes elicited in membrane structure. Membrane cholesterol was modulated by heptakis(2,6-di-O-methyl)-beta-cyclodextrin (DIMEB) and the cholesterol inclusion complex of DIMEB (Chol-DIMEB). Changes in membrane cholesterol level were reflected by alterations in the overall lipid packing as measured by Merocyanine 540 (MC540) staining and were also accompanied by changes in the raft association of the pump. DIMEB and Chol-DIMEB treatments have also lead to increased permeability of the cell membrane in both directions, raising the possibility that the effects on pumping efficiency reflect leakage of ATP also from the non-permeabilized cells. However, the treatments did not influence the intracellular ATP levels of the non-permeabilized cells. Our data suggest that Pgp inhibition by cyclodextrin treatments arises through modulation of its membrane microenvironment, rather than as a result of concomitant cytotoxicity.

Lovastatin interferes with the infarct size-limiting effect of ischemic preconditioning and postconditioning in rat hearts.

Statins have been shown to be cardioprotective; however, their interaction with endogenous cardioprotection by ischemic preconditioning and postconditioning is not known. In the present study, we examined if acute and chronic administration of the 3-hydroxy-3-methylglutaryl CoA reductase inhibitor lovastatin affected the infarct size-limiting effect of ischemic preconditioning and postconditioning in rat hearts. Wistar rats were randomly assigned to the following three groups: 1) vehicle (1% methylcellulose per os for 12 days), 2) chronic lovastatin (15 mg.kg(-1).day(-1) per os for 12 days), and 3) acute lovastatin (1% methylcellulose per os for 12 days and 50 micromol/l lovastatin in the perfusate). Hearts isolated from the three groups were either subjected to a nonconditioning (aerobic perfusion followed by 30-min coronary occlusion and 120-min reperfusion, i.e., test ischemia-reperfusion), preconditioning (three intermittent periods of 5-min ischemia-reperfusion cycles before test ischemia-reperfusion), or postconditioning (six cycles of 10-s ischemia-reperfusion after test ischemia) perfusion protocol. Preconditioning and postconditioning significantly decreased infarct size in vehicle-treated hearts. However, preconditioning failed to decrease infarct size in acute lovastatin-treated hearts, but the effect of postconditioning remained unchanged. Chronic lovastatin treatment abolished postconditioning but not preconditioning; however, it decreased infarct size in the nonconditioned group. Myocardial levels of coenzyme Q9 were decreased in both acute and chronic lovastatin-treated rats. Western blot analysis revealed that both acute and chronic lovastatin treatment attenuated the phoshorylation of Akt; however, acute but not chronic lovastatin treatment increased the phosphorylation of p42 MAPK/ERK. We conclude that, although lovastatin may lead to cardioprotection, it interferes with the mechanisms of cardiac adaptation to ischemic stress.

ABCG2 (breast cancer resistance protein/mitoxantrone resistance-associated protein) ATPase assay: a useful tool to detect drug-transporter interactions.

The ATPase assay using membrane preparations from recombinant baculovirus-infected Spodoptera frugiperda ovarian (Sf9) cells is widely used to detect the interaction of compounds with different ATP-binding cassette transporters. However, Sf9 membrane preparations containing the wild-type ABCG2 transporter show an elevated baseline vanadate-sensitive ATPase activity, which cannot be further stimulated by substrates of ABCG2. Therefore, this assay system cannot be used for the detection of ABCG2 substrates. To overcome this difficulty we 1) purified membranes from a selected human cell line expressing wild-type ABCG2, and 2) inhibited the baseline ATPase activity with different inhibitors. In our modified assay, ABCG2 substrates were able to stimulate the baseline ATPase activity of ABCG2 expressed in membranes of human cells. Furthermore, using the specific ABCG2 inhibitors Ko143 or Ko134 allowed us to suppress the baseline vanadate-sensitive ATPase activity. Substrates of ABCG2 could stimulate this suppressed baseline ATPase, resulting in a better signal-to-background ratio and a robust assay to detect substrates of the ABCG2 transporter. The ATPase assay and the direct vesicular transport measurements for estrone-3-sulfate were in good accordance.

Avaliaçäo de seis testes sorológicos no diagnóstico da brucelose bubalina / Evaluation of six serological tests for the diagnosis of brucellosis in water buffaloes

Foram examinados 440 soros bubalinos, selecionados em um outro exame de cerca de 1200 amostras sangüíneas. Utilizaram-se seis diferentes testes sorológicos para o exame dessas amostras: dois de aglutinaçäo, dois de ELISA indireto e dois de ELISA competitivo. Os animais positivos no ELISA competitivo da FAO/IAEA foram considerados como infectados, e a comparaçäo com os resultados dos outros testes aconteceu neste sentido. A sensibilidade relativa foi de 100 por cento, 98,57 por cento, 97,14 por cento, 91,42 por cento e 79,28 por cento, e a especificidade relativa de 99,33 por cento, 97,33 por cento, 95,66 por cento, 94,00 por cento e 86,33 por cento nas provas de ELISA competitivo, ELISA indireto com conjugado antibovino de cadeia leve (anticorpo monoclonal com HRPO), ELISA indireto com conjugado contra IgG bovino total, teste do antígeno acidificado tamponado e aglutinaçäo rápida, respectivamente. Discute-se o valor dos diferentes testes sorológicos no diagnóstico da brucelose

Mycobacterium tuberculosis em um grupo de macacos mantidos em cativeiro - exames bacteriológicos / Mycobacterium Tuberculis in a group of monkeys in captivity. Bacteriologic examinations

Objetivo: Identificar o agente causador de tuberculosis, ocorrida em um grupo de primatas não humanos (Cebbus apella), aproveitando diversas técnicas bacteriológicas. Método: Foram utilizadas as seguintes técnicas:demonstração direta empregadndo a coloração de Ziehl-Neelsen, inoculação em cobais e coelhos, isolamento, provas bioquímicas e reação de polimerase em cadeia (PCR). Resultados: de 18 macacos de um grupo encontrou-se cinco com tuberculose geeneralisada e um com tuberculose localizada (fígado). Em um animal, sem lesões características, nos pulmões e nos linfonodos traqueobronquiais foram demonstradas bactérias ácido e álcool resistentes através de coloração de Ziehl-Neelsen e inoculação em cobaias. Nestas duas provas foram positivos também, os seis animais com tuberculose. Todas as cepas isoladas produziram niacina e urease, reduziram o nitrato e hidrolizaram o Tween 80. Conclusão: O causador da tuberculose foi o MYcobacterium tuberculosis. Sendo que em 38,9 por cento (7/18) dos primatas a infecção por M. tuberculosis estabeleceu-se e em seis animais já desenvolveram-se lesões patológicas, o que leva a crer que o Cebus apella, mantido em cativeiro, é tão sensível à infecção pelo M. tuberculosis quanto as outras espécies de macacos

Considerações sobre o diagnóstico sorológico da leptospirose no homem e algumas espécies animais / Considerations on of serological diagnosis of leptospirosis of human and some animal species

Objetiivo: Comparar os resultados de um kit ELISA comercial com os de soraglutinação microscópica (SAM) examinando amostras de soros humanos, caninos e bovinos. Método: foram analisados amostras de soro de homens sadios e doentes, orindos da cidade de Belém e do campo; 48 caninos da cidade e do campo e 131 bovinos de sete fazendas. Os métodos efetuados foram a SAM utilizando antígeno vivo de 27 sorovare e o ELISA indireto comercial utilizando antígeno de filamento axial. Resultados: A proporção da soropositividade foi: no homem: 60,4 por cento (58/96) e 77,1 por cento &4/96); no canino: 62,5 por cento (30/48) e 79,1 por cento (38/48) e no bovino: 74,7 por cento (100/131) e 74,7 por cento (100/131) nas provas de SAM e ELISA IgG, respectivamente. Conclusão: o kit ELISA utilizado é adequado para avaliação epidemiológico sendo apto para examinar grande número de amostras em curto prazo, mas não é apto para substituir a soroaglutinação microscópica

Levantamento sorológico sobre a prevalência da infecção por Toxoplosma gondii em algumas especies animais no Estado do Pará / Serological survey on the prevalence of infection with Toxoplasma gondii in some animal species in Pará state, Brazil

Foram examinadas amostras de soro sagüíneo de 110 bovinos, 123 bubalinos, 127 caninos e 130 macacos de cinco espécies para presença de anticorpos anti-Toxoplasma gondii através de ELISA indireeto e látex-aglutinação (LA). utilizou-se um kit ELISA comercial (Clark, USA) e um LA (Patoresx-Tooxo, Sanofi). No ELISA, foi utilizado o conjugado adequado para as espécies examinaadas (Sigma). A prevalência da soropositividade foi mais alta nos caninos oriundos de fazendas (13/31, 41,8 por cento pelo ELISA e 10/31, 32,2 por cento pela LA) seguida por caninos da cidade (32/96, 33,3 por cento pelo ELISA e 27/96, 28,1 por cento pela LA), bovinos (28/110, 25,4 pelo ELISA e 20/110, 18,2 por cento pela LA) e bubalinos (15/123, 12,2 por cento pelo ELISA e 28/123, 22,8 por cento pela LA). As espécies de simios Cebus apella, Cercopitecus althiops e Ateles p. marginatus mostraram-se sororreagentes entre 63,9 por cento a 100 por cento dos animais examinados, enquanto que as Aotus infulatus e Saimiri sciures, não o foram

Prevalência de brucelose em diferentes grupos populacionais da cidade de Belém-Pa / Prevalence of brucellosis in diferent population groups of the Belem city

Foram examinadas 383 amostras de soros de diferentes grupos populacionais da cidade de Belém, para avaliar a difusäo de infecçäo por B. abortus e B. canis. Para validação da infecção por B. abortus foram utilizadas a soroaglutinação lenta (SAL), fixação do complemento (FC) e o ELISA competitivo (cELISA). A proporção de positividade em cada prova foi de 5,2 por cento, 16,7 por centeo e 7,0 por cento respectivamente. A proporção mais alta ocorreu nos trabalhadores do matadouro (23/80; 28,7 por cento) e nos médicos veterinários (3/23; 13 por cento). Para avaliação da difusão da B.canis, foi utilizada a imunodifusão em gel de ágar. Observou-se uma taxa de incidência de soros reagentes surpreendente (14,6 por cento), que superou as obtidas em outros estados do país. Acredita-se que a causa da alta prevalência seja devido a estreita cobitação entre o homem e o cão observada na cidade de BVelém e a falta de higiene

Ocorrência da leucose enzoótica dos bovinos no Estado do Pará, Brasil / Occurrence of enzootic bovine leukosis in the State of Pará, Brazil

The occurrence of the infection with Bovine Leukosis Virus (BLV) was examined in agar-gel immunodiffusion (AGID) test and with indirect enzyme-linked immunosorbent assay (ELISA), in the State of Pará, Brazil. The blood sera were collected from different breeds including Nelore, Piemontes, Simental, Holstein Frisian, Indubrasil, Girolanda, Simbrasil and their cross-breedings. The majority of the animals were adults. The overall occurrence of infections was 49.8% (359/721) and 26.0% (174/668) for ELISA and AGID test, respectively. All animal groups examined showed infection in ELISA, however in the AGID test two groups were sera negative.(AU)

A ocorrência da infecção pelo Vírus da Leucose Enzoótica dos Bovinos (BLV) no Estado do Pará, foi estudada através do método de imunodifusão em ágar-gel (AGID) e por um ensaio imunoenzimatico (ELISA) indireto, paralelamente. Os exames foram realizados com amostras de soros sanguíneos oriundos de bovinos de diferentes raças sendo a maioria deles adultos. A prevalência observada foi de 49,8% (359/721) no ELISA e 26,0% (174/668) no AGID. Todos os 14 grupos dos animais estudados pelo ELISA indireto, mostraram a existência da infeção, enquanto que pelo método da AGID, dois grupos de animais foram negativos.(AU)