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Reinoso S, Vitoria P, Ugalde M, Gutiérrez-Zorrilla JM, Luque A, Román P. tert-Butylammonium hydrogen phenyl phosphate. Acta Crystallogr C 1999. [DOI: 10.1107/s0108270198016734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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77
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Diaz J, Fernandez-Arjona M, Perandones C, Serrano E, Frau C, Cortes I, Luque A, Carbonell LF. Reference intervals for biochemistry parameters for evaluation of oxidative stress in human sperm. Clin Chem 1998; 44:2197-9. [PMID: 9761257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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78
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Kleisbauer JP, García-Girón C, Antimi M, Azevedo MC, Balmes H, Massuti-Sureda B, Contu A, Luque A, Pellier P. Granisetron plus methylprednisolone for the control of high-dose cisplatin-induced emesis. Anticancer Drugs 1998; 9:387-92. [PMID: 9660534 DOI: 10.1097/00001813-199806000-00003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This double-blind, double-dummy, randomized study compared the 24 h efficacy and safety of granisetron alone (3 mg i.v. over 30 s) or in combination with methylprednisolone (250 mg i.v. twice daily) in preventing nausea and vomiting in 308 patients (254 males) receiving high-dose cisplatin (100 mg/m2 or above) for mainly lung, and head and neck cancers. All patients received oral follow-on therapy comprising oral granisetron and methylprednisolone during the following 6 days. Primary efficacy variables were the proportions of complete responses (CR; no vomiting, no worse than mild nausea, no rescue and no withdrawal), no vomiting and no nausea over the first 24 h following initiation of the cisplatin infusion. The two treatment groups were well matched for demographics, cancer site, cisplatin dose and duration of infusion. Granisetron plus methylprednisolone was significantly more effective than granisetron alone for all primary efficacy variables: CR 78 versus 59% (p<0.001), no vomiting 80 versus 61% (p<0.001) and no nausea 74 versus 57% (p<0.002). Significantly more patients receiving the combination were free of any emetic symptoms (74 versus 54%, p<0.001). Significantly fewer patients receiving combination therapy also required rescue therapy with i.v. granisetron (12.2 versus 21.7%, p=0.026). During the follow-on period, complete response rates varied day by day from 50 to 71%. Both treatments were well tolerated, with constipation, abdominal pain and headache as the most frequent adverse events.
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79
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Quiroga AG, Pérez JM, López-Solera I, Masaguer JR, Luque A, Román P, Edwards A, Alonso C, Navarro-Ranninger C. Novel tetranuclear orthometalated complexes of Pd(II) and Pt(II) derived from p-isopropylbenzaldehyde thiosemicarbazone with cytotoxic activity in cis-DDP resistant tumor cell lines. Interaction of these complexes with DNA. J Med Chem 1998; 41:1399-408. [PMID: 9554873 DOI: 10.1021/jm970520d] [Citation(s) in RCA: 191] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The reaction of p-isopropylbenzaldehyde thiosemicarbazone [p-is.TSCN], 1, with palladium(II) acetate and potassium tetrachloroplatinate yielded two tetrameric orthopalladated isomers, [Pd(p-is.TSCN)]4 (complexes 2 and 3), and the platinum analogue [Pt(p-is.TSCN)]4 (complex 4), respectively. All of these complexes contain the thiosemicarbazone bonded as a terdentate ligand to the metallic atom, through the thiol sulfur, the azomethinic nitrogen and the ortho carbon of the p-isopropylphenyl ring to which the imine group is attached to as deduced from the study of the IR, NMR, and XRD spectra of complexes 2 and 4. Complexes 2 and 4 crystallize in the centrosymmetric monoclinic space group C2/c, with Z = 8. Unit cell parameters for complex 2 are as follows: a = 25.742(5) A, b = 19.560(4) A, c = 24.199(5) A, beta = 101.70(3)o. Unit cell parameters for complex 4 are as follows: a = 25.8728(19) A, b = 19. 5053(14) A, c = 24.0899(16) A, beta = 101.305(2)o. As can be deduced from the NMR study, the palladated isomers 2 and 3 interconvert in DMSO which may be a consequence of the existence in both complexes of a flexible eight-membered ring with alternating Pd-S atoms. The testing of the cytotoxic activity of these compounds against several human and murine cell lines sensitive and resistant to cisplatin (cis-DDP) suggests that compounds 2, 3, and 4 may be endowed with important anticancer properties since they elicit IC50 values in the microM range as does the clinically used drug cis-DDP, and, moreover, they display cytotoxic activity in tumor lines resistant to cis-DDP. The analysis of the interaction of these novel tetrameric cyclometalated compounds with DNA suggests that they form DNA interhelical cross-links.
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Carpintero P, Luque A, Serrano J. Recurrent osteochondromatosis of the shoulder in a child. Orthopedics 1998; 21:361-2. [PMID: 9547821 DOI: 10.3928/0147-7447-19980301-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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81
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Novoa B, Luque A, Castro D, Borrego JJ, Figueras A. Characterization and Infectivity of Four Bacterial Strains Isolated from Brown Ring Disease-Affected Clams. J Invertebr Pathol 1998; 71:34-41. [PMID: 9446735 DOI: 10.1006/jipa.1997.4704] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Four bacterial strains isolated from carpet-shell clams (Ruditapes decussatus) and manila clams (R. philippinarum) exhibiting Brown Ring Disease (BRD) symptoms in Galicia (Northwest of Spain) were characterized using biochemical and serological techniques. Moreover their pathogenicity for clams and resistance against clam hemolymph were determined. All of the Vibrio isolates exhibited biochemical characteristics typical of the genus. Strains GR1703RP and GR6301RP, isolated from R. philippinarum showing signs of BRD, shared phenotypical and antigenic characteristics and bacterial extracellular products enzymatic activities with the Vibrio tapetis. Strains GR0705RD and GR0202RD, isolated from R. decussatus showing BRD signs, although biochemically similar to V. tapetis, did not show positive agglutination with V. tapetis antiserum. The virulence of the bacteria varied depending on the bacterial strain and clam species assayed. Mortalities were recorded for a 30-day period, reaching values ranging from 6 to 80%. Strain GR0202RD was the most virulent for R. philippinarum with a cumulative mortality rate of 45%, while the strain GR0705RD induced the highest prevalence of BRD signs, affecting 75% of the survivors. In the case of R. decussatus, the four bacterial strains produced a cumulative mortality rate higher than 45%. In general, bacterial strains, showed resistance to clams hemolymph. Copyright 1998 Academic Press. Copyright 1998 Academic Press
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Muñoz M, Serrador J, Nieto M, Luque A, Sánchez-Madrid F, Teixidó J. A novel region of the alpha4 integrin subunit with a modulatory role in VLA-4-mediated cell adhesion to fibronectin. Biochem J 1997; 327 ( Pt 3):727-33. [PMID: 9581549 PMCID: PMC1218850 DOI: 10.1042/bj3270727] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The integrin VLA-4 (alpha4 beta1) is a receptor for fibronectin and vascular cell-adhesion molecule 1 (VCAM-1). Four functionally different epitopes, designated A, B1, B2 and C, have previously been defined on the alpha4 subunit. Using K562 alpha4 mutant transfectants we found that alpha4 amino acids Tyr151, Gln152, Asp153, Tyr154 and Val155 are important for the structure of the epitope B2. Mutations at alpha4 Gln152 substantially impaired the transfectant adhesion to a CS-1-containing fragment of fibronectin (FN-H89), whereas this adhesion was not affected on the other alpha4 mutant transfectants. None of the alpha4 mutations significantly altered the adhesion of the different alpha4 transfectants to VCAM-1. In addition, we have identified residues Gln152, Asp153 and Tyr154 as part of the alpha4 epitope B2 involved in homotypic cell aggregation. The decrease in adhesion to FN-H89 shown by Gln152 alpha4 mutant transfectants was the result of an inefficient binding of FN-H89 by VLA-4 mutated at this residue. Also, mutant VLA-4 displayed an altered reactivity with HUTS-21, an anti-beta1 monoclonal antibody that reacts with functionally active VLA integrins. Adhesion to FN-H89 was not restored unless stimuli that increase the ligand-binding affinity of VLA heterodimers were added, suggesting that cell adhesion was affected in the initial phases. These results indicate that alpha4 Gln152 modulates cell adhesion to FN-H89 by playing important roles in the maintenance and/or the acquisition of an active state of VLA-4, an integrin that is normally expressed on the cell surface in a range of multiple activation states. The location of the alpha4 Gln152 residue on a loop of the upper surface of the proposed beta-propeller structure suggests a close association with potential ligand-binding sites.
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MESH Headings
- Antibodies, Monoclonal/immunology
- Antigens, CD/biosynthesis
- Antigens, CD/genetics
- Antigens, CD/immunology
- Antigens, CD/physiology
- Cell Adhesion/genetics
- Cell Aggregation/genetics
- Cell Aggregation/immunology
- Epitopes
- Fibronectins/physiology
- Humans
- Integrin alpha4
- Integrin alpha4beta1
- Integrins/biosynthesis
- Integrins/genetics
- Integrins/immunology
- Integrins/physiology
- Intercellular Signaling Peptides and Proteins
- Killer Cells, Natural
- Mutation
- Peptides/physiology
- Receptors, Lymphocyte Homing/biosynthesis
- Receptors, Lymphocyte Homing/genetics
- Receptors, Lymphocyte Homing/immunology
- Receptors, Lymphocyte Homing/physiology
- Solubility
- Vascular Cell Adhesion Molecule-1/physiology
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83
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Luque A, Cabañas C, Raab U, Letamendia A, Páez E, Herreros L, Sánchez-Madrid F, Bernabeu C. The use of recombinant vaccinia virus to generate monoclonal antibodies against the cell-surface glycoprotein endoglin. FEBS Lett 1997; 413:265-8. [PMID: 9280294 DOI: 10.1016/s0014-5793(97)00860-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Characterization of novel cell-surface protein molecules, initially identified by cDNA cloning techniques, usually requires the generation of specific antibodies to further analyze their biochemical and/or functional properties. Here we report a simple method, using recombinant vaccinia virus, for the generation of monoclonal antibodies (mAb) to the cell-surface antigen endoglin. A recombinant vaccinia virus carrying a cDNA encoding human endoglin was inserted into the thymidine kinase locus under the control of the 7.5k vaccinia virus promoter. Infection of Balb/c mice with this recombinant virus led to the generation of specific polyclonal antibodies, as demonstrated by the antisera reactivity against human endoglin transfectants. The spleen cells of these infected animals were fused to myeloma cells, allowing efficient generation of several hybridomas which secrete mAbs to human endoglin, as evidenced by their reactivity with purified endoglin as well as with endoglin transfectants. Some of the mAbs selected seem to be specific for regions of endoglin conserved among different species as evidenced by their cross-reactivity with chicken endoglin. These results underline the utility of recombinant vaccinia virus to generate antibodies with novel properties to new cell surface proteins such as endoglin.
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84
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Castro D, Romalde JL, Vila J, Magariños B, Luque A, Borrego JJ. Intraspecific characterization of Vibrio tapetis strains by use of pulsed-field gel electrophoresis, ribotyping, and plasmid profiling. Appl Environ Microbiol 1997; 63:1449-52. [PMID: 9097443 PMCID: PMC168440 DOI: 10.1128/aem.63.4.1449-1452.1997] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
A total of twenty-two strains of Vibrio tapetis, the causative agent of brown ring disease affecting cultured clams, were compared and evaluated in an investigation of strain heterogeneity using pulsed-field gel electrophoresis (PFGE), ribotyping, and plasmid profile analysis. A total of 90.9% of V. tapetis strains tested by using NotI showed the same PFGE pattern, consisting of 15 bands. In contrast, the V. tapetis strains showed a low degree of similarity with six reference Vibrio species tested. All V. tapetis strains harbored a large plasmid of 74.5 kb. This plasmid was not detected in any of the other Vibrio species. In addition, endonuclease restriction analysis of the plasmid content of the strains using EcoRI and HindIII clearly showed that all the strains of V. tapetis possessed the same cleavage pattern. The three enzymes used for ribotyping, PvuII, SmaI, and SalI, yielded patterns with 8 to 12 bands ranging in size from 2 to 23 kb. The application of the SalI and SmaI endonuclease rendered the separation of the strains tested in two ribotypes, while all the V. tapetis strains belonged to the same ribotype when the enzyme PvuII was used.
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85
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Dal-Ré R, Aguilar L, García Losa M, Luque A. [Hospital location and the contract of drug clinical trials]. Med Clin (Barc) 1997; 108:437-8. [PMID: 9213645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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86
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Gómez M, Luque A, del Pozo MA, Hogg N, Sánchez-Madrid F, Cabañas C. Functional relevance during lymphocyte migration and cellular localization of activated beta1 integrins. Eur J Immunol 1997; 27:8-16. [PMID: 9021992 DOI: 10.1002/eji.1830270103] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The state of integrin activation can be assessed by monoclonal antibodies (mAb) that selectively recognize integrins in their active form. We demonstrate herein that the expression of the epitope recognized by mAb HUTS-21 is induced on T lymphoblasts upon binding of soluble vascular cell adhesion molecule (VCAM)-1 and an 80-kDa tryptic fragment of fibronectin (FN80) to the beta1 integrins very late activation antigen (VLA)-4 and VLA-5, and that this effect is dependent on ligand concentration and is specific for beta1 integrins. On T lymphoblasts adhering to immobilized fibronectin, the HUTS-21 epitope localized exclusively to sites of integrin binding to fibronectin. These results indicate that mAb HUTS-21 recognizes a ligand-induced binding site (LIBS) on the common beta1 subunit of VLA proteins. Engagement of beta1 integrins through this LIBS epitope inhibited T lymphoblast movement on fibronectin, as determined by quantitative time-lapse video microscopy studies. Furthermore, the HUTS-21 mAb also prevented T lymphoblast-directed migration through gradients of substratum-immobilized beta1 integrin ligands such as fibronectin or VCAM-1, whereas it did not affect migration on intercellular adhesion molecule (ICAM)-1. This anti-LIBS mAb stimulated cell adhesion through postreceptor events, without affecting receptor affinity for ligand, and appears to interfere with cell migration by a mechanism distinct from that of other anti-beta1 activating antibodies.
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87
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Luque A, del Cañizo C, Lagos R, Moehlecke A. Dynamic modelling of the diffusion-segregation gettering. Application to the gettering by Al in Si. ACTA ACUST UNITED AC 1996. [DOI: 10.1002/pssa.2211570106] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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88
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Castro D, Santamaria J, Luque A, Martinez-Manzanares E, Borrego J. Antigenic characterization of the etiological agent of the brown ring disease affecting manila clams. Syst Appl Microbiol 1996. [DOI: 10.1016/s0723-2020(96)80049-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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89
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Lledó García E, Hernández Fernández C, Escribano Patiño G, Díez Cordero JM, Moncada Iribarren I, Verdú Tartajo F, Herranz Amo F, Durán Merino R, Jara Rascón J, Luque A, Fernández Escribano A, de Palacio España A, González Chamorro F. [Lymphocele after renal transplantation: therapeutic controversies in the age of laparoscopy]. Actas Urol Esp 1996; 20:648-54. [PMID: 8975551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We present 11 lymphoceles in 180 consecutive kidney transplants (6%). We study the potential etiologic factors, symptoms, diagnostic evaluation and treatment, stressing the role of laparoscopy in management of bulky and loculated symptomatic lymphoceles. This technique allows to reduce morbidity, increasing efficacy and shortening hospitalization.
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90
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Luque A, Moehlecke A, Lagos R, Del Cañizo C. Segregation Model for Si Gettering by Al. ACTA ACUST UNITED AC 1996. [DOI: 10.1002/pssa.2211550105] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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91
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Luque A, Gómez M, Puzon W, Takada Y, Sánchez-Madrid F, Cabañas C. Activated conformations of very late activation integrins detected by a group of antibodies (HUTS) specific for a novel regulatory region (355-425) of the common beta 1 chain. J Biol Chem 1996; 271:11067-75. [PMID: 8626649 DOI: 10.1074/jbc.271.19.11067] [Citation(s) in RCA: 252] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The very late activation antigens (VLA) or beta 1 integrins mediate cell attachment to different extracellular matrix proteins and intercellular adhesions. The ligand binding activity of these adhesion receptors is not constitutive and can be regulated by temperature, presence of extracellular divalent cations, stimulatory monoclonal antibodies (mAbs), and cellular activation. We have generated three novel mAbs, HUTS-4, HUTS-7, and HUTS-21, recognizing specific epitopes on the common beta 1 subunit (CD29) of VLA integrins whose expression correlates with the ligand binding activity of these heterodimeric glycoproteins. This correlation has been demonstrated for several integrin heterodimers in different cell systems using a variety of extracellular and intracellular stimuli for integrin activation. Thus, the presence of micromolar concentrations of extracellular Mn2+, preincubation with the activating anti-beta 1 mAb TS2/16, and cell treatment with phorbol esters or calcium ionophores, induced the expression of the HUTS beta 1 epitopes on T lymphoblasts. Using a panel of human-mouse beta 1 chimeric molecules, we have mapped these epitopes to the 355-425 sequence of the beta 1 polypeptide. This segment represents therefore a novel regulatory region of beta 1 that is exposed upon integrin activation. Interestingly, binding of HUTS mAbs to partially activated VLA integrins results in maximal activation of these adhesion receptors and enhancement of cell adhesion to beta 1 integrin ligands collagen, laminin, and fibronectin.
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92
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Román P, Guzmán-Miralles C, Luque A. Estimate of two general relationships between the number of atoms and the volumes of the unit cells of compounds containing only non-metallic p-block elements. ACTA CRYSTALLOGRAPHICA SECTION B: STRUCTURAL SCIENCE 1994. [DOI: 10.1107/s0108768194005070] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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93
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Román P, San José A, Luque A, Gutiérrez-Zorrilla JM, Martínez-Ripoll M. Bis(tert-butylammonium) molybdate(VI). Acta Crystallogr C 1994. [DOI: 10.1107/s0108270193014519] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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94
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Román P, San José A, Luque A, Gutiérrez-Zorrilla JM. Hexakis(tert-butylammonium) heptamolybdate(VI)–water (1/7). Acta Crystallogr C 1994. [DOI: 10.1107/s0108270193012831] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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95
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Luque A, Sánchez-Madrid F, Cabañas C. Functional regulation of the human integrin VLA-1 (CD49a/CD29) by divalent cations and stimulatory beta 1 antibodies. FEBS Lett 1994; 346:278-84. [PMID: 7516898 DOI: 10.1016/0014-5793(94)00490-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We have investigated the regulation by divalent cations Mg2+, Ca2+ and Mn2+ of the functional activity of the human integrin VLA-1 expressed on neuroblastoma NB100 cells. VLA-1-mediated adhesion of NB100 cells to ligand collagen type I was supported by either mM concentrations of extracellular Mg2+ or microM levels of Mn2+. In contrast, Ca2+ alone did not induce activation of VLA-1 but exerted a potent inhibitory effect on the Mg(2+)-supported cell adhesion. We have also demonstrated that VLA-1 can be directly activated by the stimulatory monoclonal antibody TS2/16 specific for the integrin beta 1 subunit, resulting in effective adhesion of NB100 cells to type I collagen. This study has been possible by using a novel blocking VLA-alpha 1 specific monoclonal antibody, 5E8D9.
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96
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Luque A, Moriñigo MA, Rodríguez-Avial C, Picazo JJ, Borrego JJ. [Microbial drug resistance and the presence of plasmids in Salmonella strains isolated from different sources]. Enferm Infecc Microbiol Clin 1994; 12:187-92. [PMID: 8031884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND To establish the relationship between the presence of plasmid and their antimicrobial resistance of Salmonella strains. METHODS We tested 171 strains of Salmonella isolated from different sources: natural waters (73 strains), food (23 strains), and from clinical samples (75 strains). The disk diffusion method was used to test the antimicrobial susceptibility of the strains to 13 drugs. Plasmid analysis were performed by agarose gel electrophoresis technique. RESULTS Antimicrobial resistances of the strains significantly varies according to their primary isolation sources. Strains isolated from the water environment exhibited a full susceptibility to cephalothin and colistin, whilst all the strains isolated from food were sensitive to ampicillin, gentamicin, kanamycin, neomycin, tobramycin and trimethoprim-sulphamethoxazole. On the other hand, resistances to colistin, gentamicin and trimethoprim-sulphamethoxazole were not found in clinical isolates. From the 171 Salmonella strains tested, only 12.2% were sensitive to all the antimicrobials. The most frequently antibiotic resistances detected were to streptomycin (49.3%), tetracycline (33.1%) and nalidixic acid (30.7%). The percentage of strains that harboured plasmids was different depending on the source of isolation, ranging from 41.4% for water isolated, 76% for clinical isolates and 86.9% for food isolates. The relationship between antimicrobial resistance and plasmid presence is very close, since higher percentages of resistance to chloramphenicol, carbenicillin, cephalothin, kanamycin, neomycin, nalidixic acid and trimethoprim-sulphamethoxazole were obtained in strains containing plasmids. CONCLUSIONS (a) The most frequently resistance detected in strains of Salmonella was to streptomycin (49.3% of the strains). On the other hand, only 0.6% of the strains were resistant to gentamicin. (b) Percentages of resistance to some antibiotics was higher in strains harbouring plasmids, that implies a relationship between the plasmid presence and the antibiotic resistance in Salmonella. (c) Curing of extrachromosomic elements by acridine orange showed a percentage of resistance lost greater than 70% for cephalothin, kanamycin, neomycin, and nalidixic acid. This indicates that the resistance to those antibiotics is mainly linked to plasmids. In the case of the unusual nalidixic acid-resistance, previously described in Shigella strains, suggests that are needed more studies to demonstrate the direct association between antimicrobial resistance and presence of plasmids.
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97
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Román P, Guzmán-Miralles C, Luque A. Structure of dipotassium trans-diaquabis(oxalato-O,O')nickelate(II)–water (1/4). Acta Crystallogr C 1993. [DOI: 10.1107/s0108270193000940] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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98
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San José A, Luque A, Gutiérrez-Zorrilla JM. Crystal structure and bonding of tetrakis(tert-butylammonium) β-octamolybdate(VI) hexahydrate. Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.204.12.179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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99
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Román P, Guzmán-Miralles C, Luque A. Estimate of a relationship between the number of atoms and the volumes of the unit cells of organic compounds. ACTA CRYSTALLOGRAPHICA SECTION B: STRUCTURAL SCIENCE 1993. [DOI: 10.1107/s0108768192007201] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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100
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Román P, Beitia JI, Luque A. Structures of 2-amino-3-methylpyridinium bis(1,2–dithiooxalato-S,S')metallates(II) (M = Ni, Pd and Pt). Acta Crystallogr C 1993. [DOI: 10.1107/s0108270192010503] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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