501
|
Cardenal R, Medrano FJ, Varela JM, Ordoñez A, Regordan C, Rincon M, Martinez A, Calderon EJ. Pneumocystis carinii pneumonia in heart transplant recipients. Eur J Cardiothorac Surg 2001; 20:799-802. [PMID: 11574228 DOI: 10.1016/s1010-7940(01)00900-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
OBJECTIVES In spite of the high prevalence of Pneumocystis carinii (PC) pneumonia in immunocompromised patients, little is known about the epidemiological characteristics of this infection, and whether the cases of PC pneumonia in immunosuppressed patients are the result of a reactivation of a latent infection or a due to a recent infection is unknown. The aim of this study was to provide information about the epidemiological characteristics of PC pneumonia in a cohort of heart transplant (HT) recipients when compared with the epidemiology of PC infection in a cohort of chronic sputum producers (CSP) representative of the general population of the same geographical area. METHODS We identified all the cases of PC pneumonia in the cohort of 72 subjects who underwent cardiac transplantation at our institution between January 1991 and December 1996 and compared them with the cases of PC infection identified in a non-selected cohort of 34 CSP. This second group was included to obtain an approximation of the frequency of PC carriers in the general population. Identification of PC was accomplished through customary stain techniques and immunofluorescence with monoclonal antibodies. RESULTS Of the 72 HT recipients four (5.5%) developed PC pneumonia, but one had two episodes. Only one had received primary chemoprophylaxis, but developed PC pneumonia 2 months after discontinuing prophylactic therapy. PC pneumonia episodes were produced 53, 102, 230, 181 and 772 days after the moment of transplant, respectively. PC was identified in two (5.8%) of the 34 CSP. No significant differences were found when the accumulative incidences of PC pneumonia in HT patients and PC infection in CSP were compared (P=0.7). CONCLUSIONS The frequency of PC pneumonia among HT patients is the same as the frequency of PC infection in the general population. This observation and the long interval between transplantation and the development of PC pneumonia observed in the study support the hypothesis that the occurrence of PC pneumonia in immunocompromised patients might be from a new infection rather than from the reactivation of latent organisms. Therefore, continuous prophylaxis might be indicated in areas with a high prevalence of PC for patients at highest risk.
Collapse
|
502
|
Espinosa-de-los-Monteros J, Martinez A, Valle F. Metabolic profiles and aprE expression in anaerobic cultures of Bacillus subtilis using nitrate as terminal electron acceptor. Appl Microbiol Biotechnol 2001; 57:379-84. [PMID: 11759689 DOI: 10.1007/s002530100749] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Cultures using nitrate as the terminal electron acceptor were conducted in Schaeffer's medium to evaluate the growth performance and metabolic profiles of Bacillus subtilis, and its potential to express the aprE (subtilisin) gene under anoxic conditions. Nitrate was converted to ammonia through nitrite reduction; and different product profiles were observed during the growth phase when nitrate was added at various concentrations (4-24 mM) to Schaeffer's medium containing glucose (4 g l(-1)). If nitrate was not limiting, then acetic acid and acetoin were accumulated, suggesting a limitation of reduced cofactors but, if nitrate became limiting, then lactic acid and butanediol were accumulated, suggesting an excess of reduced cofactors. Due to a strong lysis at the onset of the end of the growth phase, sporulation frequency and aprE expression were negligible in anaerobic batch cultures. Fed-batch fermentation allowed the development of a stationary phase through a continuous supply of glucose and nitrate. In this case, sporulation frequency was almost null, but interestingly aprE expression was similar to that found in aerobic cultures.
Collapse
|
503
|
Morrissey C, Martinez A, Zatyka M, Agathanggelou A, Honorio S, Astuti D, Morgan NV, Moch H, Richards FM, Kishida T, Yao M, Schraml P, Latif F, Maher ER. Epigenetic inactivation of the RASSF1A 3p21.3 tumor suppressor gene in both clear cell and papillary renal cell carcinoma. Cancer Res 2001; 61:7277-81. [PMID: 11585766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Renal cell carcinoma (RCC), the most common adult kidney neoplasm, is histopathologically heterogeneous, with most sporadic RCCs ( approximately 80%) classified as clear cell (CC) tumors. Chromosome 3p allele loss is the most frequent genetic alteration in RCC but is associated specifically with sporadic and hereditary forms of clear cell RCC (CC-RCC) and is not a feature of non-CC-RCC, such as papillary (chromophilic) RCC. The VHL tumor suppressor gene (TSG) maps to chromosome 3p25, and somatic inactivation of the VHL gene occurs in up to 70% of CC-RCC tumors and cell lines. However, VHL inactivation is not sufficient for CC-RCC tumorigenesis, and inactivation of 3p12-p21 TSG(s) appears to be necessary in CC-RCC irrespective of VHL gene inactivation status. Recently, we demonstrated that the candidate 3p21 TSG, RASSF1A, is hypermethylated in most small cell lung cancers. We have now investigated the role of RASSF1A inactivation in primary RCC tumors. RASSF1A promoter methylation was detected in 23% (32 of 138) of primary CC-RCC tumors. In CC-RCC cell lines, RASSF1A methylation was associated with silencing of RASSF1A expression and restoration of expression after treatment with 5'-azacytidine. The frequency of RASSF1A methylation was similar in CC-RCC with and without VHL gene inactivation (24% versus 21%), and there was no association between epigenetic silencing of the RASSF1A and VHL TSGs, because 0 of 6 tumors with VHL hypermethylation had RASSF1A methylation, and VHL was not methylated in 26 CC-RCCs with RASSF1A methylation. Although 3p allele loss has been reported rarely in papillary RCC, we identified RASSF1A methylation in 44% (12 of 27) of papillary RCCs analyzed. Thus: (a) inactivation of RASSF1A is a frequent event in both CC-RCC and papillary RCC tumors; (b) there is no relationship between epigenetic silencing of RASSF1A and VHL inactivation status in CC-RCC. Fifty-four CC-RCCs analyzed for RASSF1A methylation were informative for 3p21 allele loss, and 20% (7 of 35) with 3p21 allele loss demonstrated RASSF1A methylation. All informative CC-RCCs with 3p21 allele loss and no RASSF1A methylation also demonstrated allele losses at other regions of 3p so that tumorigenesis in these cases may result from: (a) haploinsufficiency of RASSF1A; (b) inactivation of other 3p21 TSGs; or (c) inactivation of 3p TSGs from outside of 3p21. RASSF1A is the first TSG to be inactivated frequently in both papillary and CC-RCCs. The finding of frequent epigenetic inactivation of RASSF1A in papillary RCCs despite previous studies reporting infrequent 3p21 allele loss in this tumor type illustrates how the systematic identification of all major human cancer genes will require detailed analysis of the cancer genome and epigenome.
Collapse
MESH Headings
- Adenocarcinoma, Clear Cell/genetics
- Adenocarcinoma, Clear Cell/pathology
- Carcinoma, Papillary/genetics
- Carcinoma, Papillary/pathology
- Carcinoma, Renal Cell/genetics
- Carcinoma, Renal Cell/pathology
- Chromosomes, Human, Pair 3
- DNA Methylation
- Gene Expression Regulation, Neoplastic
- Gene Silencing
- Genes, Tumor Suppressor
- Humans
- Kidney Neoplasms/genetics
- Kidney Neoplasms/pathology
- Ligases
- Mutation
- Neoplasm Proteins/genetics
- Promoter Regions, Genetic
- Proteins/genetics
- Transcriptional Activation
- Tumor Suppressor Proteins
- Ubiquitin-Protein Ligases
- Von Hippel-Lindau Tumor Suppressor Protein
Collapse
|
504
|
Speghini A, Francini R, Martinez A, Tavernese M, Bettinell M. Spectroscopic properties of Er3+, Yb3 + and Er3 + /Yb3+ doped metaphosphate glasses. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2001; 57:2001-2008. [PMID: 11666080 DOI: 10.1016/s1386-1425(01)00473-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The absorption and emission spectroscopies of Er3+ doped and Er3+/Yb3+ codoped Ca(PO3)2, Sr(PO3)2 and Ba(PO3)2 glasses have been studied. From the Judd-Ofelt intensity parameters, the spontaneous emission probabilities of some relevant transitions and the radiative lifetimes of several excited states of Er3+ have been calculated. The decay curves of the Er3+ emission at 1.5 microm have been measured at different temperatures. The data have been fitted using a stretched exponential function and the obtained experimental lifetimes have been compared with the calculated radiative lifetimes. The difference between the experimental and calculated lifetimes is attributed to the presence of traces of OH groups in the host glasses. The absolute OH content in some glasses has been determined from the infrared spectra. The emission spectra at 1.5 microm of the Er3+ ion in the codoped glasses have been measured at different temperatures. The integrated emission intensities decrease significantly on passing from room temperature to 13 K, suggesting a temperature dependence of the rate of the energy transfer process between Yb3+ and Er3+.
Collapse
|
505
|
Castro A, Martinez A. Peripheral and dual binding site acetylcholinesterase inhibitors: implications in treatment of Alzheimer's disease. Mini Rev Med Chem 2001; 1:267-72. [PMID: 12369973 DOI: 10.2174/1389557013406864] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recently advances in understanding the molecular basis of Alzheimer's disease have led to the consideration of the relationship between cholinergic inhibitors and amyloid deposition as a new hypothesis for the future rational design of effective anti-Alzheimer drugs. In the present review, the non-cholinergic functions of acetylcholinesterase (AChE) and the therapeutic potential of peripheral and dual binding site AChE inhibitors in delaying the neurodegenerative process will be discussed.
Collapse
|
506
|
Avis I, Hong SH, Martinez A, Moody T, Choi YH, Trepel J, Das R, Jett M, Mulshine JL. Five-lipoxygenase inhibitors can mediate apoptosis in human breast cancer cell lines through complex eicosanoid interactions. FASEB J 2001; 15:2007-9. [PMID: 11511519 DOI: 10.1096/fj.00-0866fje] [Citation(s) in RCA: 156] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Many arachidonic acid metabolites function in growth signaling for epithelial cells, and we previously reported the expression of the major arachidonic acid enzymes in human breast cancer cell lines. To evaluate the role of the 5-lipoxygenase (5-LO) pathway on breast cancer growth regulation, we exposed cells to insulinlike growth factor-1 or transferrin, which increased the levels of the 5-LO metabolite, 5(S)-hydrooxyeicosa-6E,8C,11Z,14Z-tetraenoic acid (5-HETE), by radioimmunoassay and high-performance liquid chromatography. Addition of 5-HETE to breast cancer cells resulted in growth stimulation, whereas selective biochemical inhibitors of 5-LO reduced the levels of 5-HETE and related metabolites. Application of 5-LO or 5-LO activating protein-directed inhibitors, but not a cyclooxygenase inhibitor, reduced growth, increased apoptosis, down-regulated bcl-2, up-regulated bax, and increased G1 arrest. Exposure of breast cancer cells to a 5-LO inhibitor up-regulated peroxisome proliferator-activated receptor (PPAR)a and PPARg expression, and these same cells were growth inhibited when exposed to relevant PPAR agonists. These results suggest that disruption of the 5-LO signaling pathway mediates growth arrest and apoptosis in breast cancer cells. Additional experiments suggest that this involves the interplay of several factors, including the loss of growth stimulation by 5-LO products, the induction of PPARg, and the potential activation of PPARg by interactions with shunted endoperoxides.
Collapse
|
507
|
Gomez-Ambrosi J, Fruhbeck G, Aguado M, Milagro F, Margareto J, Martinez A. Divergent effects of an α2-adrenergic antagonist on lipolysis and thermogenesis: Interactions with a β3-adrenergic agonist in rats. Int J Mol Med 2001. [DOI: 10.3892/ijmm.8.1.103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
|
508
|
Barker K, Martinez A, Wang R, Bevan S, Murday V, Shipley J, Houlston R, Harper J. PTEN mutations are uncommon in Proteus syndrome. J Med Genet 2001; 38:480-1. [PMID: 11476065 PMCID: PMC1757185 DOI: 10.1136/jmg.38.7.480] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
509
|
Williams GS, Martinez A, Montalbano A, Tang A, Mauhar A, Ogwaro KM, Merz D, Chevillard C, Riblet R, Feeney AJ. Unequal VH gene rearrangement frequency within the large VH7183 gene family is not due to recombination signal sequence variation, and mapping of the genes shows a bias of rearrangement based on chromosomal location. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:257-63. [PMID: 11418657 DOI: 10.4049/jimmunol.167.1.257] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Much of the nonrandom usage of V, D, and J genes in the Ab repertoire is due to different frequencies with which gene segments undergo V(D)J rearrangement. The recombination signal sequences flanking each segment are seldom identical with consensus sequences, and this natural variation in recombination signal sequence (RSS) accounts for some differences in rearrangement frequencies in vivo. Here, we have sequenced the RSS of 19 individual V(H)7183 genes, revealing that the majority have one of two closely related RSS. One group has a consensus heptamer, and the other has a nonconsensus heptamer. In vitro recombination substrate studies show that the RSS with the nonconsensus heptamer, which include the frequently rearranging 81X, rearrange less well than the RSS with the consensus heptamer. Although 81X differs from the other 7183-I genes at three positions in the spacer, this does not significantly increase its recombination potency in vitro. The rearrangement frequency of all members of the family was determined in microMT mice, and there was no correlation between the in vitro recombination potential and V(H) gene rearrangement frequency in vivo. Furthermore, genes with identical RSS rearrange at different frequencies in vivo. This demonstrates that other factors can override differences in RSS potency in vivo. We have also determined the gene order of all V(H)7183 genes in a bacterial artificial chromosome contig and show that most of the frequently rearranging genes are in the 3' half of the region. This suggests that chromosomal location plays an important role in nonrandom rearrangement of the V(H)7183 genes.
Collapse
|
510
|
Martinez A, Salas E, Radomski A, Radomski MW. Matrix metalloproteinase-2 in platelet adhesion to fibrinogen: interactions with nitric oxide. Med Sci Monit 2001; 7:646-51. [PMID: 11433190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
BACKGROUND Matrix metalloproteinase-2 (MMP-2) has been shown to activate a non-thromboxane, non-ADP pathway of platelet aggregation. In contrast, nitric oxide (NO) is known to inhibit platelet adhesion and aggregation. Therefore, we have studied the release of MMP-2 during platelet adhesion to fibrinogen, the effects of phenanthrolione, an MMP-2 inhibitor, on adhesion and the interactions of inhibitor with a NO donor, S-nitroso-N-acetyl-D, L-penicillamine (SNAP). MATERIAL AND METHODS Human platelets were isolated from blood of healthy volunteers and platelet adhesion to fibrinogen-coated plates was studied by measuring thrombin-stimulated release of platelet a-granule constituent, platelet factor 4. In addition, the mode of action of phenanthroline and NO on platelets was investigated by assaying the levels of intraplatelet cyclic GMP. RESULTS Thrombin-stimulated platelet adhesion to fibrinogen was associated with increased release of MMP-2 from platelets. Phenanthroline (0.1-100 KM) reduced platelet adhesion to fibrinogen. The adhesion was also inhibited by SNAP (0.1-100 KM), an effect abolished by 1H-[1,2,4] oxadiazolol [4,3,-a] quinoxalin-1-one (ODQ), a selective inhibitor of the soluble guanylate cyclase. Co-administration of phenanthroline and SNAP resulted in a synergistic inhibition of platelet adhesion, an effect that was not associated with enhanced cyclic GMP generation by platelets. Furthermore, ODQ did not reverse the synergistic effect of these compounds on adhesion. CONCLUSIONS 1. MMP-2 promotes platelet adhesion to fibrinogen. 2. Phenanthroline and NO synergize to inhibit platelet adhesion to fibrinogen acting through a cyclic GMP-independent mechanism(s).
Collapse
|
511
|
Binks M, Passweg JR, Furst D, McSweeney P, Sullivan K, Besenthal C, Finke J, Peter HH, van Laar J, Breedveld FC, Fibbe WE, Farge D, Gluckman E, Locatelli F, Martini A, van den Hoogen F, van de Putte L, Schattenberg AV, Arnold R, Bacon PA, Emery P, Espigado I, Hertenstein B, Hiepe F, Kashyap A, Kötter I, Marmont A, Martinez A, Pascual MJ, Gratwohl A, Prentice HG, Black C, Tyndall A. Phase I/II trial of autologous stem cell transplantation in systemic sclerosis: procedure related mortality and impact on skin disease. Ann Rheum Dis 2001; 60:577-84. [PMID: 11350846 PMCID: PMC1753658 DOI: 10.1136/ard.60.6.577] [Citation(s) in RCA: 178] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Systemic sclerosis (SSc, scleroderma) in either its diffuse or limited skin forms has a high mortality when vital organs are affected. No treatment has been shown to influence the outcome or significantly affect the skin score, though many forms of immunosuppression have been tried. Recent developments in haemopoietic stem cell transplantation (HSCT) have allowed the application of profound immunosuppression followed by HSCT, or rescue, to autoimmune diseases such as SSc. METHODS Results for 41 patients included in continuing multicentre open phase I/II studies using HSCT in the treatment of poor prognosis SSc are reported. Thirty seven patients had a predominantly diffuse skin form of the disease and four the limited form, with some clinical overlap. Median age was 41 years with a 5:1 female to male ratio. The skin score was >50% of maximum in 20/33 (61%) patients, with some lung disease attributable to SSc in 28/37 (76%), the forced vital capacity being <70% of the predicted value in 18/36 (50%). Pulmonary hypertension was described in 7/37 (19%) patients and renal disease in 5/37 (14%). The Scl-70 antibody was positive in 18/32 (56%) and the anticentromere antibody in 10% of evaluable patients. Peripheral blood stem cell mobilisation was performed with cyclophosphamide or granulocyte colony stimulating factor, alone or in combination. Thirty eight patients had ex vivo CD34 stem cell selection, with additional T cell depletion in seven. Seven conditioning regimens were used, but six of these used haemoimmunoablative doses of cyclophosphamide +/- anti-thymocyte globulin +/- total body irradiation. The median duration of follow up was 12 months (3-55). RESULTS An improvement in skin score of >25% after transplantation occurred in 20/29 (69%) evaluable patients, and deterioration in 2/29 (7%). Lung function did not change significantly after transplantation. One of five renal cases deteriorated but with no new occurrences of renal disease after HSCT, and the pulmonary hypertension did not progress in the evaluable cases. Disease progression was seen in 7/37 (19%) patients after HSCT with a median period of 67 (range 49-255) days. Eleven (27%) patients had died at census and seven (17%) deaths were considered to be related to the procedure (direct organ toxicity in four, haemorrhage in two, and infection/neutropenic fever in one). The cumulative probability of survival at one year was 73% (95% CI 58 to 88) by Kaplan-Meier analysis. CONCLUSION Despite a higher procedure related mortality rate from HSCT in SSc compared with patients with breast cancer and non-Hodgkin's lymphoma, the marked impact on skin score, a surrogate marker of mortality, the trend towards stabilisation of lung involvement, and lack of other treatment alternatives justify further carefully designed studies. If future trials incorporate inclusion and exclusion criteria based on this preliminary experience, the predicted procedure related mortality should be around 10%.
Collapse
|
512
|
Martinez A, Fernandez-Arquero M, Balsa A, Rubio A, Alves H, Pascual-Salcedo D, Martin-Mola E, de la Concha EG. Primary association of a MICA allele with protection against rheumatoid arthritis. ARTHRITIS AND RHEUMATISM 2001; 44:1261-5. [PMID: 11407684 DOI: 10.1002/1529-0131(200106)44:6<1261::aid-art217>3.0.co;2-l] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To determine whether major histocompatibility complex class I chain-related gene A (MICA) polymorphisms are associated with susceptibility to rheumatoid arthritis (RA) independently of the HLA-DRB1 shared epitope (SE). METHODS Fifty-four Spanish families with an affected son or daughter and 211 consecutive RA patients were genotyped for HLA-DRB1, tumor necrosis factor a/b microsatellite alleles, and MICA transmembrane polymorphism. We performed a case-control comparison with the consecutive patients and an independent transmission disequilibrium test with the families. RESULTS The frequency of the MICA 6.0 allele was significantly reduced, compared with controls, in the group of SE+ patients (odds ratio 0.39, P = 0.0005). Additionally, the haplotypes containing this allele were preferentially not transmitted to the affected offspring (9 transmitted of 33; P = 0.007), independent of the presence or absence of an SE either in the same haplotype or in the other haplotype in the progenitor. CONCLUSION These data suggest that the MICA 6.0 allele is an independent marker of protection against RA in the SE+ group of RA patients.
Collapse
|
513
|
Zheng D, Upton RN, Ludbrook GL, Martinez A. Acute cardiovascular effects of magnesium and their relationship to systemic and myocardial magnesium concentrations after short infusion in awake sheep. J Pharmacol Exp Ther 2001; 297:1176-83. [PMID: 11356944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2023] Open
Abstract
The temporal relationship between the systemic and myocardial concentrations of magnesium and some of its acute cardiovascular effects were examined after short i.v. infusion administration of magnesium (30 mmol over 2 min) in five awake chronically instrumented sheep. Magnesium decreased mean arterial blood pressure and systemic vascular resistance (SVR) by 23 and 41% from baseline, respectively. These hemodynamic changes were consistent with magnesium producing primary reductions in SVR with partial heart rate (HR)-mediated compensation of blood pressure. Cardiac output and HR increased by 38 and 38% from baseline, respectively. Magnesium had little effect on myocardial contractility, but substantially increased myocardial blood flow (MBF, 77% above baseline) primarily due to direct myocardial vasodilation. The peak arterial and coronary sinus serum magnesium concentrations were 6.94 +/- 0.26 (mean +/- S.E.M.) and 6.51 +/- 0.20 mM, respectively, at 2 min. Both arterial and coronary sinus magnesium concentrations at the end of the study were still more than 3 mM, whereas all the cardiovascular effects were back to baseline. The myocardial kinetics of magnesium was consistent with rapid equilibration of magnesium (half-life 0.4 min) with a small distribution volume (71 ml) consistent with the extracellular space of the heart. In conclusion, magnesium was shown to have a rapid equilibration between the plasma/serum concentrations of magnesium and its extracellular concentration in the myocardium. However, the primary cardiovascular effect of magnesium (reductions in SVR) preceded its extracellular concentrations, and was a direct function of its arterial concentration. A "threshold" model for changes in SVR was preferred when linked to the arterial magnesium concentration.
Collapse
|
514
|
Dubowitz DJ, Chen DY, Atkinson DJ, Scadeng M, Martinez A, Andersen MB, Andersen RA, Bradley WG. Direct comparison of visual cortex activation in human and non-human primates using functional magnetic resonance imaging. J Neurosci Methods 2001; 107:71-80. [PMID: 11389943 DOI: 10.1016/s0165-0270(01)00353-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We report a technique for functional magnetic resonance imaging (fMRI) in an awake, co-operative, rhesus macaque (Macaca mulatta) in a conventional 1.5T clinical MR scanner, thus accomplishing the first direct comparison of activation in visual cortex between humans and non-human primates with fMRI. Activation was seen in multiple areas of striate and extra-striate visual cortex and in areas for motion, object and face recognition in the monkey and in homologous visual areas in a human volunteer. This article describes T1, T2 and T2* values for macaque cortex, suitable MR imaging sequences, a training schedule, stimulus delivery apparatus and restraining hardware for monkey fMRI using a conventional 19 cm knee coil. Much of our understanding of the functional organization of the primate brain comes from physiological studies in monkeys. Direct comparison between species using fMRI such as those described here will help us to relate the wealth of existing knowledge on the functional organization of the non-human primate brain to human fMRI.
Collapse
|
515
|
Martinez A, Castro A, Gil C, Perez C. Recent strategies in the development of new human cytomegalovirus inhibitors. Med Res Rev 2001; 21:227-44. [PMID: 11301412 DOI: 10.1002/med.1008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Human cytomegalovirus (HCMV) is one of the most common opportunistic infections in immunucompromised individuals, such as AIDS patients and organ transplant recipients, and is the most frequent congenital viral infection in humans. Despite a reduction of the incidence of AIDS-related opportunistic infections in patients under highly active antiretroviral treatment, attention should be paid to the HCMV risk factor in these individuals. Furthermore, HCMV may have an important role in atherosclerosis. Existing antiviral treatments for the HCMV infection suffer from poor bioavailability, toxicity, and limited effectiveness, mainly due to the development of drug resistance. Fortunately there are novel and potentially very effective new compounds undergoing pre-clinical and clinical evaluation. This review provides an overview in the last five years of new HCMV inhibitors (chemical structures, SAR, and new mechanisms of action) with the aim to provide new clues for the development of future drugs against this opportunistic virus.
Collapse
|
516
|
Tao H, Gonzalez R, Martinez A, Rodriguez M, Ingram LO, Preston JF, Shanmugam KT. Engineering a homo-ethanol pathway in Escherichia coli: increased glycolytic flux and levels of expression of glycolytic genes during xylose fermentation. J Bacteriol 2001; 183:2979-88. [PMID: 11325924 PMCID: PMC95196 DOI: 10.1128/jb.183.10.2979-2988.2001] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Replacement of the native fermentation pathway in Escherichia coli B with a homo-ethanol pathway from Zymomonas mobilis (pdc and adhB genes) resulted in a 30 to 50% increase in growth rate and glycolytic flux during the anaerobic fermentation of xylose. Gene array analysis was used as a tool to investigate differences in expression levels for the 30 genes involved in xylose catabolism in the parent (strain B) and the engineered strain (KO11). Of the 4,290 total open reading frames, only 8% were expressed at a significantly higher level in KO11 (P < 0.05). In contrast, over half of the 30 genes involved in the catabolism of xylose to pyruvate were expressed at 1.5-fold- to 8-fold-higher levels in KO11. For 14 of the 30 genes, higher expression was statistically significant at the 95% confidence level (xylAB, xylE, xylFG, xylR, rpiA, rpiB, pfkA, fbaA, tpiA, gapA, pgk, and pykA) during active fermentation (6, 12, and 24 h). Values at single time points for only four of these genes (eno, fbaA, fbaB, and talA) were higher in strain B than in KO11. The relationship between changes in mRNA (cDNA) levels and changes in specific activities was verified for two genes (xylA and xylB) with good agreement. In KO11, expression levels and activities were threefold higher than in strain B for xylose isomerase (xylA) and twofold higher for xylulokinase (xylB). Increased expression of genes involved in xylose catabolism is proposed as the basis for the increase in growth rate and glycolytic flux in ethanologenic KO11.
Collapse
|
517
|
Ozbun LL, You L, Kiang S, Angdisen J, Martinez A, Jakowlew SB. Identification of differentially expressed nucleolar TGF-beta1 target (DENTT) in human lung cancer cells that is a new member of the TSPY/SET/NAP-1 superfamily. Genomics 2001; 73:179-93. [PMID: 11318608 DOI: 10.1006/geno.2001.6505] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The transforming growth factor-beta1 (TGF-beta1) responsive epithelial non-small-cell lung cancer (NSCLC) cell line NCI-H727 was used to identify potential target genes involved in TGF-beta1-mediated responses. Comparative cDNA expression patterns between cells treated with TGF-beta1 and those treated with vehicle were generated by differential mRNA display. One 496-bp fragment, differentially increased threefold by TGF-beta1 and hybridizing to a 2.7-kb mRNA species in NCI-H727 cells by Northern analysis, revealed no significant match to any known gene sequence. The mRNA transcript of this novel gene that we named differentially expressed nucleolar TGF-beta1 target (DENTT) is expressed in several normal human tissues, with the highest level of expression in brain. Human brain cDNA library screening and 5' rapid amplification of cDNA ends yielded full-length DENTT cDNA containing an 1899-bp open reading frame encoding a predicted 633-amino-acid protein with four potential nuclear localization signals (NLSs) and two coiled-coil regions. DENTT contains a conserved 191-residue domain that shows significant identity to, and defines, the TSPY/TSPY-like/SET/NAP-1 superfamily. Enhanced green fluorescent protein (EGFP)-tagged full-length DENTT transfected into COS-7 cells showed nucleolar and cytoplasmic localization. Transfection of EGFP-tagged DENTT NLS deletion constructs lacking the bipartite NLS-1 were excluded from the nucleolus. While NLS-1 is necessary for nucleolar localization of DENTT, it is not sufficient for sole nucleolar localization. Our data show that DENTT mRNA induction by TGF-beta1 correlates with induction of TGF-beta1 mRNA, induction of extracellular matrix gene expression, and inhibition of colony formation in soft agarose in TGF-beta1 responsive NSCLC cells when exposed to TGF-beta1. TGF-beta1 does not induce DENTT mRNA expression in TGF-beta1 nonresponsive NSCLC cells. Our data suggest that this novel TGF-beta1 target gene has distinct domains for direction to different subnuclear locations.
Collapse
|
518
|
Pio R, Martinez A, Unsworth EJ, Kowalak JA, Bengoechea JA, Zipfel PF, Elsasser TH, Cuttitta F. Complement factor H is a serum-binding protein for adrenomedullin, and the resulting complex modulates the bioactivities of both partners. J Biol Chem 2001; 276:12292-300. [PMID: 11116141 DOI: 10.1074/jbc.m007822200] [Citation(s) in RCA: 192] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Adrenomedullin (AM) is an important regulatory peptide involved in both physiological and pathological states. We have previously demonstrated the existence of a specific AM-binding protein (AMBP-1) in human plasma. In the present study, we developed a nonradioactive ligand blotting assay, which, together with high pressure liquid chromatography/SDS-polyacrylamide gel electrophoresis purification techniques, allowed us to isolate AMBP-1 to homogeneity. The purified protein was identified as human complement factor H. We show that AM/factor H interaction interferes with the established methodology for quantification of circulating AM. Our data suggest that this routine procedure does not take into account the AM bound to its binding protein. In addition, we show that factor H affects AM in vitro functions. It enhances AM-mediated induction of cAMP in fibroblasts, augments the AM-mediated growth of a cancer cell line, and suppresses the bactericidal capability of AM on Escherichia coli. Reciprocally, AM influences the complement regulatory function of factor H by enhancing the cleavage of C3b via factor I. In summary, we report on a potentially new regulatory mechanism of AM biology, the influence of factor H on radioimmunoassay quantification of AM, and the possible involvement of AM as a regulator of the complement cascade.
Collapse
|
519
|
Martinez A, Regadera J, Jimenez E, Santos I, Gargallo-Viola D. Antifungal efficacy of GM237354, a sordarin derivative, in experimental oral candidiasis in immunosuppressed rats. Antimicrob Agents Chemother 2001; 45:1008-13. [PMID: 11257009 PMCID: PMC90418 DOI: 10.1128/aac.45.4.1008-1013.2001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
GM237354 is a novel sordarin derivative with a broad spectrum of potent activity against a wide range of fungi. The members of this new class of antifungal agents act as potent inhibitors of fungal protein synthesis. In this study, the therapeutic effects of GM237354 were investigated in a novel experimental oral Candida albicans infection model in immunosuppressed rats. The animals were immunosuppressed with dexamethasone in their drinking water and infected on three alternate days. GM237354 was given three times per day for seven consecutive days at 1.25, 2.5, 5, or 10 mg/kg of body weight per dose. In addition, to provide a preliminary idea of the correlation between regimen administration and therapeutic efficacy, GM237354 was administered to two additional groups of rats at 5 mg/kg once or twice a day for 7 days. The drug efficacy was assessed microbiologically, histologically, and by a morphometric study of lesions. Evident agreement was observed among results obtained by the different methods in all of the animals studied. Microbiologically, the efficacy of GM237354 was determined by measuring the number of C. albicans organisms in the oral cavities of rats in the middle (day 4) and at the end (day 7) of the treatment. GM237354 administered at 5, 7.5, 10, 15, or 30 mg/kg/day for 7 days significantly reduced the number of CFU in the oral cavities of treated rats compared with the number of CFU in the oral cavities of the untreated controls. A significant reduction was also observed when GM237354 was administered at 7.5, 10, 15, or 30 mg/kg/day for 4 days. Furthermore, C. albicans was not detected in oral swabs from any infected rats after 1 week of treatment when GM237354 was administered at 15 or 30 mg/kg/day or after 4 days of treatment at 30 mg/kg/day. Histologically, untreated control animals showed extensive colonization of the epithelium of the dorsal tongue by numerous hyphae. Animals treated with GM237354 at 7.5 mg/kg/day showed small areas with superficial hyphal penetration into the epithelium that produced intraepithelial microabscesses. However, animals treated with GM237354 at 15 mg/kg/day showed multiple regenerative areas of the covering epithelium, and only focalized zones of the tongue surface were occupied by hyphae. No hyphal colonization of the epithelium was seen in rats treated with GM237354 at 30 mg/kg/day and which showed extensive areas of epithelial regeneration of the tongue. The histopathology findings were confirmed by morphometry studies, and the percentage of epithelium occupied by C. albicans hyphae decreased from 17.5% in the control group to 4.8 and 0.1% in animals treated with GM237354 at 7.5 and 15 mg/kg/day, respectively. These results demonstrated that the sordarin derivative GM237354 was effective against experimental oral candidiasis in immunosuppressed rats, and further studies are needed to determine the potential of GM237354 for use in the treatment of this infection in humans.
Collapse
|
520
|
Upton RN, Ludbrook GL, Grant C, Martinez A. In vivo cerebral pharmacokinetics and pharmacodynamics of diazepam and midazolam after short intravenous infusion administration in sheep. J Pharmacokinet Pharmacodyn 2001; 28:129-53. [PMID: 11381567 DOI: 10.1023/a:1011550915515] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The cerebral pharmacokinetics and pharmacodynamics of midazolam and diazepam were examined in chronically instrumented sheep via measurements of their arterio-venous concentration difference across the brain during and after 2-min i.v. infusions. Diazepam (30 mg) or midazolam (10 mg) were administered on 5 separate occasions to 4 sheep. For both drugs, rapid cerebral uptake occurred during the infusion, which quickly turned to elution in the postinfusion period. However, this process was more rapid for midazolam than diazepam. The cerebral pharmacokinetics of both was better described by a kinetic model with slight membrane limitation rather than flow limitation. For diazepam, the estimated brain:plasma partition coefficient was 2.67, and the first and second compartments filled with half-lives of 2.2 and 0.5 min, respectively. For midazolam, these values were 0.27, 0.26 and 1.34 min, respectively. In a subset of sheep, pulmonary arterial-arterial gradients were too small to measure suggesting limited metabolism and small distribution volumes for both drugs in the lungs. Simultaneous dynamic measurements of cerebral blood flow and algesimetry lagged behind both the arterial and sagittal sinus blood concentrations. The changes in cerebral blood flow were best described by a previously published a dynamic model that incorporated long half-lives for drug dissociation from the benzodiazepine receptor (13.3 and 5.5 min for midazolam and diazepam, respectively). Effect compartment modeling of the cerebral blood flow data showed apparent effect compartment half-lives (t1/2,keo) that were longer than the half-lives of cerebral equilibration.
Collapse
|
521
|
Castro A, Abasolo MI, Gil C, Segarra V, Martinez A. CoMFA of benzyl derivatives of 2,1,3-benzo and benzothieno[3,2-alpha]thiadiazine 2,2-dioxides: clues for the design of phosphodiesterase 7 inhibitors. Eur J Med Chem 2001; 36:333-8. [PMID: 11461758 DOI: 10.1016/s0223-5234(01)01227-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A CoMFA study of benzo- and benzothienothiadiazines derivatives as phosphodiesterase 7 inhibitors has been carried out in order to determine the factors required for the activity of these compounds and also for the selectivity versus other phosphodiesterase isoenzymes. This methodology is employed to gain clues on the design of new fused thiadiazines with improved activity and selectivity on phosphodiesterase 7. Using the information achieved from the three CoMFA models, new structures have been designed in silico and their inhibitory activity on phosphodiesterase 7 was predicted.
Collapse
|
522
|
Vicini FA, Baglan KL, Kestin LL, Mitchell C, Chen PY, Frazier RC, Edmundson G, Goldstein NS, Benitez P, Huang RR, Martinez A. Accelerated treatment of breast cancer. J Clin Oncol 2001; 19:1993-2001. [PMID: 11283132 DOI: 10.1200/jco.2001.19.7.1993] [Citation(s) in RCA: 184] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Radiation therapy (RT) restricted to the tumor bed, by means of an interstitial implant, and lasting 4 to 5 days after lumpectomy was prospectively evaluated in early-stage breast cancer patients treated with breast-conserving therapy (BCT). The goals of the study were to determine whether treatment time can be reduced and whether elective treatment of the entire breast is necessary. MATERIALS AND METHODS Between January 1993 and January 2000, 174 cases of early-stage breast cancer were managed with lumpectomy followed by RT restricted to the tumor bed using an interstitial implant. Each brachytherapy patient was matched with one external-beam RT (ERT) patient derived from a reference group of 1,388 patients treated with standard BCT. Patients were matched for age, tumor size, histology, margins of excision, absence of an extensive intraductal component, nodal status, estrogen receptor status, and tamoxifen use. Median follow-up for both the ERT and brachytherapy groups was 36 months. RESULTS No statistically significant differences were noted in the 5-year actuarial rates of ipsilateral breast treatment failure or locoregional failure between ERT and brachytherapy patients (1% v 0%, P =.31 and 2% v 1%, P =.63, respectively). In addition, there were no statistically significant differences noted in rates of distant metastasis (6% v 3%, P =.24), disease-free survival (87% v 91%, P =.55), overall survival (90% v 93%, P =.66), or cause-specific survival (97% v 99%, P =.28). CONCLUSION Accelerated treatment of breast cancer using an interstitial implant to deliver radiation to the tumor bed alone over 4 to 5 days seems to produce 5-year results equivalent to those achieved with conventional ERT. Extended follow-up will be required to determine the long-term efficacy of this treatment approach.
Collapse
|
523
|
Agathanggelou A, Honorio S, Macartney DP, Martinez A, Dallol A, Rader J, Fullwood P, Chauhan A, Walker R, Shaw JA, Hosoe S, Lerman MI, Minna JD, Maher ER, Latif F. Methylation associated inactivation of RASSF1A from region 3p21.3 in lung, breast and ovarian tumours. Oncogene 2001; 20:1509-18. [PMID: 11313894 DOI: 10.1038/sj.onc.1204175] [Citation(s) in RCA: 298] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2000] [Revised: 12/01/2000] [Accepted: 12/15/2000] [Indexed: 02/06/2023]
Abstract
Previously we analysed overlapping homozygous deletions in lung and breast tumours/tumour lines and defined a small region of 120 kb (part of LCTSGR1) at 3p21.3 that contained putative lung and breast cancer tumour suppressor gene(s) (TSG). Eight genes including RASSF1 were isolated from the minimal region. However, extensive mutation analysis in lung tumours and tumour lines revealed only rare inactivating mutations. Recently, de novo methylation at a CpG island associated with isoform A of RASSF1 (RASSF1A) was reported in lung tumours and tumour lines. To investigate RASSF1A as a candidate TSG for various cancers, we investigated: (a) RASSF1A methylation status in a large series of primary tumour and tumour lines; (b) chromosome 3p allele loss in lung tumours and (c) RASSF1 mutation analysis in breast tumours. RASSF1A promoter region CpG island methylation was detected in 72% of SCLC, 34% of NSCLC, 9% of breast, 10% of ovarian and 0% of primary cervical tumours and in 72% SCLC, 36% NSCLC, 80% of breast and 40% of ovarian tumour lines. In view of the lower frequency of RASSF1 methylation in primary breast cancers we proceeded to RASSF1 mutation analysis in 40 breast cancers. No mutations were detected, but six single nucleotide polymorphisms were identified. Twenty of 26 SCLC tumours with 3p21.3 allelic loss had RASSF1A methylation, while only six out of 22 NSCLC with 3p21.3 allele loss had RASSF1A methylation (P=0.0012), one out of five ovarian and none out of six cervical tumours with 3p21.3 loss had RASSF1A methylation. These results suggest that (a) RASSF1A inactivation by two hits (methylation and loss) is a critical step in SCLC tumourigenesis and (b) RASSF1A inactivation is of lesser importance in NSCLC, breast, ovarian and cervical cancers in which other genes within LCTSGR1 are likely to be implicated.
Collapse
|
524
|
Salvador-Carulla L, Romero C, Martinez A, Haro JM, Bustillo G, Ferreira A, Gaite L, Johnson S. Assessment instruments: standardization of the European Service Mapping Schedule (ESMS) in Spain. Acta Psychiatr Scand Suppl 2001; 405:24-32. [PMID: 11129095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
OBJECTIVE To adapt the European Service Mapping Schedule (ESMS) for use in Spain and assess the quality of this schedule. METHOD Following linguistic and conceptual translation, 77 services in five Spanish catchment areas were described by independent local raters, including two experts in health services research. Feasibility (applicability. acceptability and practicality), descriptive validity and overall percentage agreement were assessed. RESULTS ESMS feasibility was considered adequate. The tree system facilitates reporting and comparison of data. Face, content and discriminant validity are adequate for almost all services. The overall reliability was high but completion of the service utilization section required expert supervision. The ESMS revealed large differences in service availability and utilization in the five different areas of Spain. CONCLUSION The ESMS has proved useful for describing mental health services in Spain, and facilitates comparisons between catchment areas.
Collapse
|
525
|
Martinez A, Rodriguez ME, Wells ML, York SW, Preston JF, Ingram LO. Detoxification of dilute acid hydrolysates of lignocellulose with lime. Biotechnol Prog 2001; 17:287-93. [PMID: 11312706 DOI: 10.1021/bp0001720] [Citation(s) in RCA: 251] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The hydrolysis of hemicellulose to monomeric sugars by dilute acid hydrolysis is accompanied by the production of inhibitors that retard microbial fermentation. Treatment of hot hydrolysate with Ca(OH)(2) (overliming) is an effective method for detoxification. Using ethanologenic Escherichia coli LY01 as the biocatalyst, our results indicate that the optimal lime addition for detoxification varies and depends on the concentration of mineral acids and organic acids in each hydrolysate. This optimum was shown to be readily predicted on the basis of the titration of hydrolysate with 2 N NaOH at ambient temperature to either pH 7.0 or pH 11.0. The average composition of 15 hydrolysates prior to treatment was as follows (per L): 95.24 +/- 7.29 g sugar, 5.3 +/- 2.99 g acetic acid, 1.305 +/- 0.288 g total furans (furfural and hydroxymethylfurfural), and 2.86 +/- 0.34 g phenolic compounds. Optimal overliming resulted in a 51 +/- 9% reduction of total furans, a 41 +/- 6% reduction in phenolic compounds, and a 8.7 +/- 4.5% decline in sugar. Acetic acid levels were unchanged. Considering the similarity of microorganisms, it is possible that the titration method described here may also prove useful for detoxification and fermentation processes using other microbial biocatalysts.
Collapse
|