A Kondo lattice antiferromagnet CePd5Al2 (2007)
Ribeiro, R. A., Onimaru, T., Umeo, K., Avila, M. A., Shigetoh, K., Takabatake, T.
We report on the electrical resistivity, magnetic susceptibility and heat-capacity measurements on a new intermetallic compound CePd5Al2, crystallizing in the ZrNi2Al5-type tetragonal structure, with...
Azoubel,M.C.F., Menezes,A.M.A., Bezerra,D., Oriá,R.B., Ribeiro,R.A., Brito,G.A.C.
We investigated the effect of etoricoxib, a selective cyclooxygenase-2 inhibitor, and indomethacin, a non-selective cyclooxygenase inhibitor, on experimental periodontitis, and compared their...
A model of hemorrhagic cystitis induced with acrolein in mice (2006)
Brito,G.A.C., Souza,M.L.P., Leitão,B.T.A., Cunha,F.Q., Ribeiro,R.A.
Acrolein is a urinary metabolite of cyclophosphamide and ifosfamide, which has been reported to be the causative agent of hemorrhagic cystitis induced by these compounds. A direct cytotoxic effect of...
A model of hemorrhagic cystitis induced with acrolein in mice (2006)
Brito,G.A.C., Souza,M.L.P., Leitão,B.T.A., Cunha,F.Q., Ribeiro,R.A.
Acrolein is a urinary metabolite of cyclophosphamide and ifosfamide, which has been reported to be the causative agent of hemorrhagic cystitis induced by these compounds. A direct cytotoxic effect of...
Azoubel,M.C.F., Menezes,A.M.A., Bezerra,D., Oriá,R.B., Ribeiro,R.A., Brito,G.A.C.
We investigated the effect of etoricoxib, a selective cyclooxygenase-2 inhibitor, and indomethacin, a non-selective cyclooxygenase inhibitor, on experimental periodontitis, and compared their...
Park, Jeong Young, Ogletree, D. Frank, Salmeron, Miquel, Ribeiro, R.A., Canfield, P.C., Jenks, C.J., ...
Long-term ethanol intoxication reduces inflammatory responses in rats (2005)
Carvalho,E.M., Brito,G.A.C., Ribeiro,R.A., Capaz,F.R.
The anti-inflammatory effects of long-term ethanol intoxication were determined during ethanol treatment and withdrawal on the basis of neutrophil and eosinophil migration, hind paw edema and mast...
Hidden Superconductivity in Solid Solutions Sr(1-x)La(x)PbO3 detected by tunneling (2004)
Drozd, V. A., Ekino, T., Gabovich, A. M., Pekala, M., Ribeiro, R. A.
Solid solutions of Sr1-xLaxPbO3 (x = 0, 0.05, 0.10, 0.15 and 0.20) were synthesized with the help of high pressure. Temperature (T) dependences of the resistivity r and differential thermoelectric...
Electrical resistivity and tunneling anomalies in CeCuAs2 (2004)
Sampathkumaran, E. V., Ekino, T., Ribeiro, R. A., Sengupta, Kausik, Nakano, T., Hedo, M., ...
The compound CeCuAs2 is found to exhibit negative temperature (T) coefficient of electrical resistivity (rho) under ambient pressure conditions in the entire T-range of investigation (45 mK to 300...
Anisotropy and internal field distribution of MgB2 in the mixed state at low temperatures (2004)
Angst, M., Di Castro, D., Eshchenko, D. G., Khasanov, R., Kohout, S., Savic, I. M., ...
Magnetization and muon spin relaxation on MgB2 were measured as a function of field at 2 K. Both indicate an inverse-squared penetration depth strongly decreasing with increasing field H below about...
Critical fluctuations in the carbon-doped magnesium diboride (2004)
Hol'anova, Z., Kačmarčik, J., Szabó, P., Samuely, P., Sheikin, I., Ribeiro, R. A., ...
Carbon doping of magnesium diboride resulting in the Mg(B0.9C0.1)(2) stoichiometry leads to the superconducting transition temperature T-c = 22 K which is about 17 K less than in the pure MgB2. We...
Absence of a boron isotope effect in the magnetic penetration depth of MgB$_{2}$ (2003)
Di Castro, D., Angst, M., Eshchenko, D. G., Khasanov, R., Roos, J., Savić, I. M., ...
The magnetic penetration depth $\lambda(0)$ in polycrystalline MgB$_{2}$ for different boron isotopes ($^{10}$B/$^{11}$B) was investigated by transverse field muon spin rotation. No boron isotope...
Disorder effects at low temperatures in La_{0.7-x}Y_{x}Ca_{0.3}MnO_{3} manganites (2003)
Gusmao, M. A., Ghivelder, L., Freitas, R. S., Ribeiro, R. A., De Lima, O. F., Damay, F., ...
With the aim of probing the effect of magnetic disorder in the low-temperature excitations of manganites, specific-heat measurements were performed in zero field, and in magnetic fields up to 9 T in...
Samuely, P., Holanova, Z., Szabo, P., Kacmarcik, J., Ribeiro, R. A., Bud'ko, S. L., ...
The Andreev reflection measurements of the superconducting energy gap in the carbon-substituted MgB$_2$ are presented. Despite the strong suppression of the transition temperature by 17 K in...
Simon, F., Janossy, A., Feher, T., Muranyi, F., Garaj, S., Forro, L., ...
The magnetic field dependence of the spin-susceptibility, $\chi_{s}$ was measured in the superconducting state of high purity MgB$_{2}$ fine powders below 1.3 T. $\chi_{s}$ was determined from the...
Crystal Chemistry of Carbon-Substituted MgB2 (2003)
Avdeev, M., Jorgensen, J. D., Ribeiro, R. A., Bud'ko, S. L., Canfield, P. C.
Neutron powder diffraction has been used to characterize a sample of C-substituted MgB2 synthesized from Mg and B4C (with isotopically enriched 11B). The sample is multiphase, with the major phase...
Ribeiro, R. A., Bud'ko, S. L., Petrovic, C., Canfield, P. C.
By synthesizing MgB$_{2}$ using boron of different nominal purity we found values of the residual resistivity ratio ($RRR = R(300 K) / R(42 K)$) from 4 to 20, which covers almost all values found in...
Synthesis and Properties of YbB2 (2002)
Avila, M. A., Bud'ko, S. L., Petrovic, C., Ribeiro, R. A., Canfield, P. C., Tsvyashchenko, A. V., ...
We report temperature and field dependent measurements of the magnetic susceptibility, specific heat and resistivity of sintered YbB2 pellets, prepared via two distinct reaction routes, utilizing...
Carbon doping of superconducting magnesium diboride (2002)
Ribeiro, R. A., Bud'ko, S. L., Petrovic, C., Canfield, P. C.
We present details of synthesis optimization and physical properties of nearly single phase carbon doped MgB2 with a nominal stoichiometry of Mg(B{0.8}C{0.2})2 synthesized from magnesium and boron...
Low-dose doxycycline prevents inflammatory bone resorption in rats (2002)
Bezerra,M.M., Brito,G.A.C., Ribeiro,R.A., Rocha,F.A.C.
Matrix metalloproteinases (MMP) are considered to be key initiators of collagen degradation, thus contributing to bone resorption in inflammatory diseases. We determined whether subantimicrobial...
Ribeiro, R. A., Bud`ko, S. L., Petrovic, C., Canfield, P. C.
We present a study of the effects of non-stoichiometry, boron purity, wire diameter and post-synthesis treatment (etching and Mg distilling) on the temperature dependent resistance and resistivity of...
Avila, M. A., Civale, L., Silhanek, A. V., Ribeiro, R. A., De Lima, O. F., Lanza, H.
We have measured the irreversible magnetization M_i of an ErBa_2Cu_3O_7 single crystal with columnar defects (CD), using a technique based on sample rotation under a fixed magnetic field H. This...
Anisotropic superconducting properties of aligned MgB2 crystallites (2001)
De Lima, O. F., Ribeiro, R. A., Avila, M. A., Cardoso, C. A., Coelho, A. A.
Samples of aligned MgB2 crystallites have been prepared, allowing for the first time the direct identification of an upper critical field anisotropy Hc2^{ab}/Hc2^{c}= xi_{ab}/xi_{c} ~ 1.73; with...
Morais,M.M., Belarmino-Filho,J.N., Brito,G.A.C., Ribeiro,R.A.
Chemotherapy with oxazaphosphorines, such as cyclophosphamide (CYP), is often limited by unacceptable urotoxicity. Without uroprotection, hemorrhagic cystitis (HC) becomes dose-limiting. To compare...
Brito,G.A.C., Saraiva,S.N.R., Lima,A.A.M., Flores,C.A., Ribeiro,R.A.
In the present study, histopathological analysis of rat mesentery was used to quantify the effect of two anti-inflammatory agents, dexamethasone (Dex) and pertussis toxin (Ptx), on leukocyte...
Rocha, M. F. G., Soares, A. M., Flores, C. A., Steiner, T. S., Lyerly, D. M., Guerrant, R. L., ...
Clostridium difficile toxin A is associated with enterocolitis in animals and humans. However, the mechanisms of its secretory and damaging effects are not totally understood. In this work, we...
Role of pertussis toxin A subunit in neutrophil migration and vascular permeability.
Brito, G A, Souza, M H, Melo-Filho, A A, Hewlett, E L, Lima, A A, Flores, C A, ...
The anti-inflammatory activity of pertussis toxin (Ptx) was compared to that of a noncatalytic mutant of pertussis toxin (9K/129G; Ptxm), which contains two amino acid substitutions in the A...
Rocha, M F, Maia, M E, Bezerra, L R, Lyerly, D M, Guerrant, R L, Ribeiro, R A, ...
Clostridium difficile produces a potent enterotoxin and cytotoxin, toxins A and B, respectively, which appear to be responsible for pseudomenbranous colitis and antibiotic-associated diarrhea. In the...
Cavalcante, I. C., Castro, M. V., Barreto, A. R. F., Sullivan, G. W., Vale, M., Almeida, P. R. C., ...
Clostridium difficile is a spore-forming, anaerobic, gram-positive bacillus that releases two main virulence factors: toxins A and B. Toxin A plays an important pathogenic role in antibiotic-induced...
Rocha, M. F. G., Soares, A. M., Flores, C. A., Steiner, T. S., Lyerly, D. M., Guerrant, R. L., ...
Clostridium difficile toxin A is associated with enterocolitis in animals and humans. However, the mechanisms of its secretory and damaging effects are not totally understood. In this work, we...
Role of pertussis toxin A subunit in neutrophil migration and vascular permeability.
Brito, G A, Souza, M H, Melo-Filho, A A, Hewlett, E L, Lima, A A, Flores, C A, ...
The anti-inflammatory activity of pertussis toxin (Ptx) was compared to that of a noncatalytic mutant of pertussis toxin (9K/129G; Ptxm), which contains two amino acid substitutions in the A...
Rocha, M F, Maia, M E, Bezerra, L R, Lyerly, D M, Guerrant, R L, Ribeiro, R A, ...
Clostridium difficile produces a potent enterotoxin and cytotoxin, toxins A and B, respectively, which appear to be responsible for pseudomenbranous colitis and antibiotic-associated diarrhea. In the...
Cavalcante, I. C., Castro, M. V., Barreto, A. R. F., Sullivan, G. W., Vale, M., Almeida, P. R. C., ...
Clostridium difficile is a spore-forming, anaerobic, gram-positive bacillus that releases two main virulence factors: toxins A and B. Toxin A plays an important pathogenic role in antibiotic-induced...
The pharmacological profile of ovalbumin-induced paw oedema in rats.
Feitosa, R F G, Melcíades, G B, Assreuy, A M S, Rocha, M F G, Ribeiro, R A, Lima, A A M
Rats are commonly used in anaphylaxis models, mainly in intestinal anaphylaxis. Hypersensitivity mechanisms are complex and they are not clearly defined. Ovalbumin (OVA) is commonly used for studies...
Leguminous lectins as tools for studying the role of sugar residues in leukocyte recruitment.
Alencar, N M, Teixeira, E H, Assreuy, A M, Cavada, B S, Flores, C A, Ribeiro, R A
The natural physiological ligands for selectins are oligosaccharides found in glycoprotein or glycolipid molecules in cell membranes. In order to study the role of sugar residues in the in vivo...
Souza, M H, Melo-Filho, A A, Rocha, M F, Lyerly, D M, Cunha, F Q, Lima, A A, ...
Clostridium difficile (Cd) toxins appear to mediate the inflammatory response in pseudomembranous colitis and/or colitis associated with the use of antibiotics. In contrast to Cd Toxin A (TxA), Cd...
IL-8 causes in vivo neutrophil migration by a cell-dependent mechanism.
Ribeiro, R A, Flores, C A, Cunha, F Q, Ferreira, S H
A dose-dependent neutrophil migration was observed following the injection of recombinant interleukin-8 (rIL-8) into rat peritoneal cavities. This finding contrasts with the inability of rIL-8 to...
Ribeiro, R. A., Lucca, F. L. De, Flores, C. A., Cunha, F. Q., Ferreira, S. H.
The effect of exogenous RNA on many cellular functions has been studied in a variety of eukaryotic cells but there are few reports on macrophages. In the present study, it is demonstrated that...
Cardoso, R. A., Filho, A. A. Melo, Melo, M. C. C., Lyerly, D. M., Wilkins, T. D., Lima, A. A. M., ...
This study investigated the ability of Clostridium difficile toxin B, isolated from the VPI 10463 strain, to induce fever and neutrophilia in rats. Intravenous injection of toxin B (0.005–0.5...
Thomazzi, S. M., Ribeiro, R. A., Campos, D. I., Cunha, F. Q., Ferreira, S. H.
It has been suggested that the supernatant of LPSstimulated macrophages (macrophage nociceptive factor, MNF) promotes nociception in mice. Intraperitoneal administration of MNF induced dose-related...
Anti-inflammatory effect of glucose—mannose binding lectins isolated from Brazilian beans
Assreuy, A. M. S., Shibuya, M. D., Martins, G. J., Cavada, B. S., Moreira, R. A., ...
Selectins are essential for leukocyte recruitment in inflammation. Because of a lectin domain present in the selectin structure, we investigated the anti-inflammtory activity of six mannose–glucose...