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Brammer G, Gibly R, Walter FG, Bey T, Torres R, Kohler S. Continuous intravenous flumazenil infusion for benzodiazepine poisoning. VETERINARY AND HUMAN TOXICOLOGY 2000; 42:280-1. [PMID: 11003118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
This is the first US report of continuous iv flumazenil infusion for benzodiazepine poisoning. A MEDLINE search from 1966 to 1999 revealed no similar reports in the US literature. A 24-y-o woman ingested 50, 2 mg (=100 mg) flunitrazepam tablets in a suicide attempt. She presented 30 min after ingestion with a temperature of 36.5 C, blood pressure of 90/36 mmHg, pulse of 84/min, and shallow respirations of 8/min. Her Glasgow coma scale (GCS) was 8. Her ECG showed sinus rhythm at 80/min, a QRS axis of 30 with no terminal 40 msec deviation, and a QRS interval of 84 msec. She received 0.2 mg flumazenil iv and her GCS improved to 15. She was orogastrically lavaged and given 50 g of activated charcoal. Resedation to a GCS of 8 recurred twice, requiring additional 0.3 mg and 0.5 mg boluses of flumazenil iv, totaling 1.0 mg over 1 h. Then, a continuous flumazenil infusion was started at 1.0 mg/h, maintaining her GCS at 15. Fourteen h later, the continuous flumazenil infusion was terminated, resulting in resedation and clinical hypoventilation. Flumazenil infusion was restarted at 1.0 mg/h with resolution of sedation and hypoventilation. Thirty h after overdose flumazenil infusion was terminated without resedation or hypoventilation. Continuous iv flumazenil infusion is not US Food and Drug Administration approved, and further study is necessary in carefully selected patients to determine its safety and efficacy.
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Walsh TJ, Gonzalez CE, Piscitelli S, Bacher JD, Peter J, Torres R, Shetti D, Katsov V, Kligys K, Lyman CA. Correlation between in vitro and in vivo antifungal activities in experimental fluconazole-resistant oropharyngeal and esophageal candidiasis. J Clin Microbiol 2000; 38:2369-73. [PMID: 10835005 PMCID: PMC86806 DOI: 10.1128/jcm.38.6.2369-2373.2000] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Oropharyngeal and esophageal candidiasis (OPEC) is a frequent opportunistic mycosis in immunocompromised patients. Azole-resistant OPEC is a refractory form of this infection occurring particularly in human immunodeficiency virus (HIV)-infected patients. The procedures developed by the Antifungal Subcommittee of the National Committee for Clinical Laboratory Standards (NCCLS) are an important advance in standardization of in vitro antifungal susceptibility methodology. In order to further understand the relationship between NCCLS methodology and antifungal therapeutic response, we studied the potential correlation between in vitro susceptibility to fluconazole and in vivo response in a rabbit model of fluconazole-resistant OPEC. MICs of fluconazole were determined by NCCLS methods. Three fluconazole-susceptible (FS) (MIC, </=0.125 microgram/ml) and three fluconazole-resistant (FR) (MIC, >/=64 microgram/ml) isolates of Candida albicans from prospectively monitored HIV-infected children with OPEC were studied. FR isolates were recovered from children with severe OPEC refractory to fluconazole, and FS isolates were recovered from those with mucosal candidiasis responsive to fluconazole. Fluconazole at 2 mg/kg of body weight/day was administered to infected animals for 7 days. The concentrations of fluconazole in plasma were maintained above the MICs for FS isolates throughout the dosing interval. Fluconazole concentrations in the esophagus were greater than or equal to those in plasma. Rabbits infected with FS isolates and treated with fluconazole had significant reductions in oral mucosal quantitative cultures (P < 0.001) and tissue burden of C. albicans in tongue, soft palate, and esophagus (P < 0.001). In comparison, rabbits infected with FR isolates were unresponsive to fluconazole and had no reduction in oral mucosal quantitative cultures or tissue burden of C. albicans versus untreated controls. We conclude that there is a strong correlation between in vitro fluconazole susceptibility by NCCLS methods and in vivo response to fluconazole therapy of OPEC due to C. albicans.
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203
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Torres R, Calle C, Aller P, Mata F. Etoposide stimulates 1,25-dihydroxyvitamin D3 differentiation activity, hormone binding and hormone receptor expression in HL-60 human promyelocytic cells. Mol Cell Biochem 2000; 208:157-62. [PMID: 10939640 DOI: 10.1023/a:1007089632152] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The simultaneous administration of the DNA topoisomerase II inhibitor etoposide (0.15 mM) and 1,25-dihydroxyvitamin D3 (VD3) (10 nM) synergistically induced the differentiation of HL-60 human promyelocytic leukemia cells. Similar results were obtained using U-937 human promonocytic cells, or the topoisomerase II inhibitors doxorubicin (15 nM) and mitoxantrone (2.5 nM). When sequential treatments were used, pre-incubation with VD3 had little effect on the subsequent action of etoposide, while pre-incubation with etoposide greatly potentiated the subsequent action of VD3. In addition, etoposide treatment stimulated VD3 binding activity and increased VD3 receptor mRNA and protein levels. The increase in hormone receptor expression may explain, at least in part, the capacity of topoisomerase inhibitors to potentiate the differentiation inducing activity of VD3.
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204
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Prum RO, Torres R, Kovach C, Williamson S, Goodman SM. Coherent light scattering by nanostructured collagen arrays in the caruncles of the malagasy asities (Eurylaimidae: aves). J Exp Biol 1999; 202 Pt 24:3507-22. [PMID: 10574729 DOI: 10.1242/jeb.202.24.3507] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We investigated the anatomy, nanostructure and biophysics of the structurally coloured facial caruncles of three species in a clade of birds endemic to Madagascar (Philepittinae, Eurylaimidae: Aves). Caruncle tissues of all species had reflectance spectra with prominent, peak hues between 403 and 528 nm. Dark blue Neodrepanis tissues had substantial reflectance in the near ultraviolet (320–400 nm), which is visible to birds but not to humans, providing the first evidence of ultraviolet skin colours in birds and the first indications of the possible function of ultraviolet skin colours in avian communication. These structural colours are produced by coherent scattering from arrays of parallel collagen fibres in the dermis. Tissues of Philepitta castanea were organized into hexagonal, crystal-like arrays, whereas Neodrepanis tissues were quasiordered. Predictions of the peak hues of reflectance (λ (max)) using Bragg's law were relatively accurate, but Bragg's law requires physical assumptions that are obviously violated by these structures. A two-dimensional discrete Fourier analysis of the spatial variation in refractive index within the tissues documented that all the tissues are substantially nanostructured at the appropriate spatial scale to scatter visible light coherently. Predicted reflectance spectra based on the two-dimensional Fourier power spectra are relatively accurate at predicting the hue and shape of the reflectance spectra of the tissues. These results confirm that the nanostructure of the collagen arrays determines the colours that are coherently scattered by these tissues. The evolution of the anatomy and nanostructure of asity caruncles is discussed.
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205
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Torres R, Ramón F, de la Mata I, Acebal C, Castillón MP. Enhanced production of penicillin V acylase from Streptomyces lavendulae. Appl Microbiol Biotechnol 1999; 53:81-4. [PMID: 10645628 DOI: 10.1007/s002530051618] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A 28 degrees C, Streptomyces lavendulae produced high levels of penicillin V acylase (178 IU/l of culture) when grown on skim milk as the sole nutrient source for 275 h. The enzyme showed catabolite repression by glucose and was produced in the stationary phase of growth. Penicillin V was a good inducer of penicillin V acylase formation, while phenoxyacetic acid, the side-chain moiety of penicillin V, did not alter enzyme production significantly. The enzyme was stable between pH 6 and 11 and at temperatures from 20 degrees C to 55 degrees C. This extracellular enzyme was able to hydrolyse natural penicillins and unable to hydrolyse penicillin G.
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206
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Torres R, Ide SE, Dehejia A, Baras A, Polymeropoulos MH. Genomic structure and localization of the human protein phosphatase 2A BRgamma regulatory subunit. DNA Res 1999; 6:323-7. [PMID: 10574460 DOI: 10.1093/dnares/6.5.323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In the course of our analysis of genomic sequence from the human chromosome 4p16.1 region harboring both the Wolfram and Ellis van Creveld syndrome genes we have identified a sequence with high homology (98% at the amino acid level) to the rat cDNA coding for the protein phosphatase 2A BRgamma (PP2ABRgamma) regulatory subunit. Although the human cDNAs for both the BRalpha and BRbeta isoforms have been described previously, the BRgamma subunit has not yet been identified in humans. Here we describe the precise genomic organization and genetic localization of the human PP2ABRgamma gene.
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207
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Stutzin A, Torres R, Oporto M, Pacheco P, Eguiguren AL, Cid LP, Sepúlveda FV. Separate taurine and chloride efflux pathways activated during regulatory volume decrease. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 277:C392-402. [PMID: 10484326 DOI: 10.1152/ajpcell.1999.277.3.c392] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Organic osmolyte and halide permeability pathways activated in epithelial HeLa cells by cell swelling were studied by radiotracer efflux techniques and single-cell volume measurements. The replacement of extracellular Cl- by anions that are more permeant through the volume-activated Cl- channel, as indicated by electrophysiological measurements, significantly decreased taurine efflux. In the presence of less-permeant anions, an increase in taurine efflux was observed. Simultaneous measurement of the 125I, used as a tracer for Cl-, and [3H]taurine efflux showed that the time courses for the two effluxes differed. In Cl--rich medium the increase in I- efflux was transient, whereas that for taurine was sustained. Osmosensitive Cl- conductance, assessed by measuring changes in cell volume, increased rapidly after hypotonic shock. The influx of taurine was able to counteract Cl- conductance-dependent cell shrinkage but only approximately 4 min after triggering cell swelling. This taurine-induced effect was blocked by DIDS. Differences in anion sensitivity, the time course of activation, and sensitivity to DIDS suggest that the main cell swelling-activated permeability pathways for taurine and Cl- are separate.
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208
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Loder F, Mutschler B, Ray RJ, Paige CJ, Sideras P, Torres R, Lamers MC, Carsetti R. B cell development in the spleen takes place in discrete steps and is determined by the quality of B cell receptor-derived signals. J Exp Med 1999; 190:75-89. [PMID: 10429672 PMCID: PMC2195560 DOI: 10.1084/jem.190.1.75] [Citation(s) in RCA: 636] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Only mature B lymphocytes can enter the lymphoid follicles of spleen and lymph nodes and thus efficiently participate in the immune response. Mature, long-lived B lymphocytes derive from short-lived precursors generated in the bone marrow. We show that selection into the mature pool is an active process and takes place in the spleen. Two populations of splenic B cells were identified as precursors for mature B cells. Transitional B cells of type 1 (T1) are recent immigrants from the bone marrow. They develop into the transitional B cells of type 2 (T2), which are cycling and found exclusively in the primary follicles of the spleen. Mature B cells can be generated from T1 or T2 B cells. Mice with genetic deletions of elements participating in the B cell receptor signaling cascade display developmental arrest at the T1 or T2 stage. The analysis of these defects showed that the development of T2 and mature B cells from T1 precursors requires defined qualitative and quantitative signals derived from the B cell receptor and that the induction of longevity and maturation requires different signals.
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Santamaria LF, Torres R, Giménez-Arnau AM, Giménez-Camarasa JM, Ryder H, Palacios JM, Beleta J. Rolipram inhibits staphylococcal enterotoxin B-mediated induction of the human skin-homing receptor on T lymphocytes. J Invest Dermatol 1999; 113:82-6. [PMID: 10417623 DOI: 10.1046/j.1523-1747.1999.00639.x] [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: 11/20/2022]
Abstract
The cutaneous lymphocyte-associated antigen defines T lymphocytes with cutaneous tropism under inflammatory conditions. Bacterial infections participate in cutaneous inflammations, such as atopic dermatitis or psoriasis. Bacterial superantigens, such as staphylococcal enterotoxin B, can activate peripheral blood mononuclear cells to induce effector T cells bearing the T cell skin homing receptor cutaneous lymphocyte-associated antigen via enhancement of interleukin-12 production. We have identified and characterized the anti-inflammatory effects of different phosphodiesterase inhibitors on this system. Our data indicate that the selective type 4 phosphodiesterase inhibitor rolipram inhibits the Staphylococcal enterotoxin B-mediated generation of cutaneous lymphocyte-associated antigen positive CD3+ cells from peripheral blood mononuclear cells by reducing interleukin-12 production in a concentration-dependent manner. Conversely, type 3 phosphodiesterase or type 5 phosphodiesterase selective inhibitors were not effective. The rolipram inhibitory effect was on interleukin-12 production, as exogenously added interleukin-12 could revert rolipram suppression. These results suggest that selective type 4 phosphodiesterase inhibition may have beneficial effects on T cell mediated skin inflammatory processes characterized by the presence of bacterial infections, that are thought to exacerbate ongoing skin inflammation.
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210
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Lissi EA, Modak B, Torres R, Escobar J, Urzua A. Total antioxidant potential of resinous exudates from Heliotropium species, and a comparison of the ABTS and DPPH methods. Free Radic Res 1999; 30:471-7. [PMID: 10400459 DOI: 10.1080/10715769900300511] [Citation(s) in RCA: 208] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Total reactive antioxidant potential (TRAP) of resinous exudates from Heliotropium species was evaluated by measuring the bleaching of stable free radicals. The antioxidant capacity of the resinous exudates in Trolox equivalents, evaluated from the bleaching of ABTS derived radical cations, ranged from 2.0 M (H. huascoense) to 5.2 M (H. stenophyllum), indicating a very high concentration of phenolic compounds. Considerably smaller values were obtained by measuring the bleaching of DPPH radicals. The ratio between the values obtained employing ABTS derived radicals and DPPH, ranged from 37 (H. megalanthum) to 4.5 (H. chenopodiaceum variety typica). The magnitude of the difference can be considered as an indication of the relative reactivity of the antioxidants present in the exudates. Similar ratios were observed when stoichiometric coefficients were evaluated for representative purified flavonoids obtained from the resinous exudates.
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211
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Cordero ME, Valenzuela CY, Torres R. [Sexual dimorphism in human medial raphe nuclei. Preliminary study with the Golgi cox method]. Rev Med Chil 1999; 127:532-8. [PMID: 10451622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Brains from a female and a male newborn who died from an asphictic syndrome were examined to study the cytoarchitecture of the median raphe nucleus using the Golgi-Cox and morphometric methods. This nucleus is part of the serotonergic system. The morphometric analysis showed in the female newborn a significant increase of neurons. Also she had a higher proportion of ovoid and multipolar cells and a lower proportion of fusiform cells than the newborn male. Our findings suggest that this neuronal distribution may be the anatomical substrate for a serotonergic specific system in each sex.
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Vasquez S, Cabezas C, Garcia B, Torres R, Larrabure G, Suarez M, Lucen A, Pernaz G, Gonzales L, Miranda G, Davalos E, Galarza C, Camasca N, Jara R. [PREVALENCE OF HBsAg AND anti-HBs CARRIERS IN PREGNANT WOMEN WHO RESIDE IN DIFFERENT ENDEMIC AREAS LOCATED IN CENTRAL-SOUTHERN DEPARTAMENTS OF PERU]. REVISTA DE GASTROENTEROLOGIA DEL PERU : ORGANO OFICIAL DE LA SOCIEDAD DE GASTROENTEROLOGIA DEL PERU 1999; 19:110-115. [PMID: 12196812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
The present study was performed to estimate the prevalence of HBV in pregnant women (mean age among groups 25,0 6,9) who live in areas of different endemicity, and located in the Departments of Lima, Junin, Apurimac, and Ayacucho in Peru. All studies were carried out using radioimmunological techniques. In the Instituto Materno Perinatal in Lima, located in a low endemical area, 2086 pregnant women whose ages ranged between 14 and 44 years were evaluated (for laboratory tests) at their first prenatal examination. A prevalence of 9,38% (HbsAG+), 0,38% (Ratio), and 3,18% (HBsAg+, anti-HBsAg+) was found, corresponding to 107 HBsAg+ pregnant women whose treated newborn wouId prevent the HBV chronic infection of approximate 21 newborn each year. 63% HBsAg+ pregnant women were born in Departments other than Lima. In the Hospital de Apoyo La Merced, located in Chanchamayo, Junin, which is a medium endemic area, 217 pregnant women whose ages ranged between 14 and 48 years were evaluated. The prevalence found in this Hospital was of 1,38% (HBsAg+), 1,2% (Ratio), and 17,8% (HBsAg+, anti-HBs+). All positive HBsAg were negative for HBeAg. The projection of results corresponded to a total of 9 HbsAg+ pregnant women and 2 newborn preventive of chronic disease per year. In the Guillermo D az de la Vega Hospital in Abancay, Apurimac, located in a medium to high endemic area, 221 pregnant women whose ages ranged between 15 and 46 years were evaluated. A prevalence of 1,36% (HBsAg+), 1,0% (Ratio), and 36,16% (HBsAg+, anti-HBs+) was found. All positive HBsAg were negative for HBeAg. Projected results corresponded to a total of 37 HBsAg+ pregnant carriers and 7 newborn preventive of chronic disease per year. The Hospital General de Huanta, in Ayacucho, located in a high endemicity area, presented a prevalence of 3,2% (HBsAg+), 1,9% (Ratio), and 76,2% (HBsAg+, anti-HBs+) from 126 pregnant women evaluated with ages between 15 and 48 years old. These results gave a total projection per year of 39 HBsAg+ pregnant women and 8 newborn preventive of chronic hepatic disease. Among a total of 4 positive HBsAg cases, 3 positive pregnant women were studied for HBeAg. All 3 were negative. These results establish the prevalence of HbsAg and antiHBs in pregnant women from different endemical areas with significant prevalence in the Departments of Ayacucho (Huanta), and Apurimac (Abancay). They also contribute towards the costbenefit analysis for the prevention of HBV chronic infection.
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Santamaria LF, Torres R, Ryder H, Beleta J, Palacios JM. Prostaglandin E2 inhibits SEB-mediated induction of the cutaneous lymphocyte-associated antigen. Int Arch Allergy Immunol 1999; 118:351-2. [PMID: 10224443 DOI: 10.1159/000024132] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Abstract
The Collapsin Response Mediator Protein-1 (CRMP-1) is a brain specific protein considered to be involved in the collapsin-induced growth cone collapse during neural development. CRMP-1 belongs to the Unc-33 gene family. Here we report the genomic structure and the localization of the human CRMP-1 gene to chromosome 4p16.1. Sequence analysis revealed that the human CRMP-1 gene consists of 14 exons. We have also established sequencing assays for all its coding exons. This should permit the rapid screening for mutations to assess CRMP-1 role in genetic disorders mapped in the 4p16.1 region.
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215
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Lavedan C, Leroy E, Torres R, Dehejia A, Dutra A, Buchholtz S, Nussbaum RL, Polymeropoulos MH. Genomic organization and expression of the human beta-synuclein gene (SNCB). Genomics 1998; 54:173-5. [PMID: 9806846 DOI: 10.1006/geno.1998.5556] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The beta-synuclein protein is highly homologous to the alpha-synuclein protein for which two mutations were reported in some familial cases of Parkinson disease. It has been shown that both alpha- and beta-synucleins may be able to inhibit phospholipase D2 selectively. We have observed that the beta-synuclein gene (HGMW-approved symbol, SNCB) is highly expressed in brain including the substantia nigra, the main region of neuronal degeneration in patients with Parkinson disease. We have determined the intron-exon structure of the beta-synuclein gene and established sequencing assays that will facilitate the search for mutations in the beta-synuclein gene in patients with Parkinson disease or other neurodegenerative disorders.
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216
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Knutsen T, Mickley LA, Ried T, Green ED, du Manoir S, Schröck E, Macville M, Ning Y, Robey R, Polymeropoulos M, Torres R, Fojo T. Cytogenetic and molecular characterization of random chromosomal rearrangements activating the drug resistance gene, MDR1/P-glycoprotein, in drug-selected cell lines and patients with drug refractory ALL. Genes Chromosomes Cancer 1998; 23:44-54. [PMID: 9713996 DOI: 10.1002/(sici)1098-2264(199809)23:1<44::aid-gcc7>3.0.co;2-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Drug resistance, both primary and acquired, is a major obstacle to advances in cancer chemotherapy. In vitro, multidrug resistance can be mediated by P-glycoprotein (PGY1), a cell surface phosphoglycoprotein that acts to efflux natural products from cells. PGY1 is encoded by the MDR1 gene located at 7q21.1. Overexpression of MDR1 has been demonstrated in many cancers, both in patient tumors and in cell lines selected with a variety of chemotherapeutic agents. Recent studies in drug-selected cell lines and patients samples have identified hybrid mRNAs comprised of an active, but apparently random, gene fused 5' to MDR1. This observation indicates that random chromosomal rearrangements, such as translocations and inversions, leading to "capture" of MDR1 by constitutively expressed genes may be a mechanism for activation of this gene following drug exposure. In this study, fluorescence in situ hybridization (FISH) using whole chromosome paints (WCP) and bacterial artificial chromosome (BAC)-derived probes showed structural rearrangements involving 7q in metaphase and interphase cells, and comparative genomic hybridization (CGH) revealed high levels of amplification at chromosomal breakpoints. In an adriamycin-selected resistant colon cancer line (S48-3s/Adr), WCP4/WCP7 revealed t(4;7)(q31;q21) and BAC-derived probes demonstrated that the breakpoint lay between MDR1 and sequences 500-1000 KB telomeric to it. Similarly, in a subline isolated following exposure to actinomycin D (S48-3s/ActD), a hybrid MDR1 gene composed of heme oxygenase-2 sequences (at 16p13) fused to MDR1 was identified and a rearrangement confirmed with WCP7 and a subtelomeric 16p probe. Likewise, in a paclitaxel-selected MCF-7 subline where CASP sequences (at 7q22) were shown to be fused to MDR1, WCP7 showed an elongated chromosome 7 with a homogeneously staining regions (hsr); BAC-derived probes demonstrated that the hsr was composed of highly amplified MDR1 and CASP sequences. In all three selected cell lines, CGH demonstrated amplification at breakpoints involving MDR1 (at 7q21) and genes fused to MDR1 at 4q31, 7q22, and 16p13.3. Finally, in samples obtained from two patients with drug refractory ALL, BAC-derived probes applied to archived marrow cells demonstrated that a breakpoint occurred between MDR1 and sequences 500-1000 KB telomeric to MDR1, consistent with a random chromosomal rearrangement. These results support the proposal that random chromosomal rearrangement leading to capture and activation of MDR1 is a mechanism of acquired drug resistance.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics
- Antibiotics, Antineoplastic/pharmacology
- Chromosome Aberrations
- Chromosome Disorders
- Chromosomes, Human, Pair 7/genetics
- Dactinomycin/pharmacology
- Doxorubicin/pharmacology
- Drug Resistance, Microbial/genetics
- Drug Resistance, Multiple/genetics
- Gene Expression Regulation/genetics
- Gene Rearrangement
- Genes, MDR/genetics
- Humans
- In Situ Hybridization, Fluorescence
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics
- Tumor Cells, Cultured/drug effects
- Tumor Cells, Cultured/metabolism
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Mogollón L, Rodríguez R, Larrota W, Ramirez N, Torres R. Biosorption of nickel using filamentous fungi. Appl Biochem Biotechnol 1998; 70-72:593-601. [PMID: 9627396 DOI: 10.1007/bf02920171] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nickel (Ni) uptake capability from aqueous solutions was studied in a filamentous fungi strains group of Rhizopus sp., Penicillium sp. Aspergillus sp., Trichoderma sp., Byschoclamyss sp., and Mucor sp. The metal uptake of a Rhizopus sp. strain, which has the highest uptake capacity, was corroborated by electron microscopy; no Ni deposits were observed on the cell wall, but rather a homogeneous accumulation was seen on the cell surface. The influence on the capacity of metal uptake by environmental parameters such as pH, temperature, time, and the interference of other ions in the solution, was also studied. Nickel accumulation by the selected strains is fast, occurring in less than 30 min, and does not require a microorganism's active metabolism to take place. The sorption isotherms were established for the selected fungi, in order to determine the maximum metal uptake capacity. The sorption isotherms were fixed to the mathematical models of Freundlich and Langmuir, obtaining better performance on the Langmuir model.
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Lee EA, Weiss SL, Lam M, Torres R, Diamond J. A method for assaying intestinal brush-border sucrase in an intact intestinal preparation. Proc Natl Acad Sci U S A 1998; 95:2111-6. [PMID: 9482847 PMCID: PMC19267 DOI: 10.1073/pnas.95.5.2111] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Small intestinal brush-border hydrolases usually are assayed in intestinal mucosal homogenates resuspended in solutions of unphysiological ionic composition. Thus, extrapolation of measured Vmax values (maximal reaction rates at high substrate concentrations) to in vivo conditions, hence comparison with physiological substrate loads, is uncertain. We therefore have developed a sucrase assay in an intact preparation of mouse small intestine, an everted intestinal sleeve incubated in a physiological Ringer's solution. As in homogenate studies, sucrase is assayed by glucose production measured colorimetrically, but uptake of liberated glucose into the intestinal sleeve is prevented by the transport inhibitor phlorizin. The coefficient of variation of Vmax is 16% for sleeves from the same mouse and 8% for mean values from different mice. Sleeve sucrase activity is abolished by the inhibitor castanospermine. Activity in sleeves and homogenates proves to be the same when measured under identical solution conditions, but variations in assay conditions cause large activity changes from values measured in physiological solutions.
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219
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Abstract
BACKGROUND/PURPOSE Down's syndrome is a common association in patients with anorectal malformations. The purpose of this study was to determine whether the anorectal defect in patients with Down's syndrome had specific characteristics and whether the presence of Down's syndrome represented a serious detriment to the patient's functional prognosis. METHODS Nine hundred eighty-seven patients with anorectal malformations were studied retrospectively. Twenty patients (2%) had Down's syndrome. Nineteen of these (95%) had the same specific type of anorectal defect: imperforate anus with no fistula. This defect has a good prognosis, the rectum is located about 2 cm above the perineal skin, the sacrum is normal, and the sphincter mechanism is good. For comparison, a group of 34 patients with the same defect but without Down's syndrome was also studied. All patients were operated on via posterior sagittal approach by the same surgeon. RESULTS Imperforate anus without fistula occurs in 5% of all patients with anorectal malformations and in 95% of those patients who also suffer from Down's syndrome. The characteristics of the defect were the same in both groups of patients, and surprisingly, the prognosis was good in both groups (80% to 96% of patients had voluntary bowel movement, 100% had urinary continence). CONCLUSIONS The association of Down's syndrome with imperforate anus without fistula is not coincidental. This particular benign defect can be predicted to occur in most patients with Down's syndrome. The presence of Down's syndrome in cases of anorectal malformations should not be a contraindication to repairing the imperforate anus and to closing the colostomy.
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Swift RG, Polymeropoulos MH, Torres R, Swift M. Predisposition of Wolfram syndrome heterozygotes to psychiatric illness. Mol Psychiatry 1998; 3:86-91. [PMID: 9491819 DOI: 10.1038/sj.mp.4000344] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Identification of specific genes that predispose to psychiatric illness will lead to more precise psychiatric diagnosis and more effective treatment. Heterozygous carriers of genes for many autosomal recessive syndromes may be 1% or more of the general population. Thus, if mutations at a specific locus produce psychiatric manifestations in homozygous affected individuals, it is important to determine whether mutations at such a locus also predispose heterozygous carriers to psychiatric disorders. The hypothesis that heterozygous carriers of the gene for the Wolfram syndrome (WS) are predisposed to psychiatric illness was supported previously by the finding of an excess of psychiatric hospitalizations and suicides in WS blood relatives compared to spouse controls. This hypothesis has now been tested further by comparing the number of psychiatrically hospitalized blood relatives with the specific marker haplotype associated with the Wolfram syndrome gene in their families to the number expected under the null hypothesis, calculated from Mendelian inheritance principles and the estimated haplotype frequency. The proportion of psychiatrically hospitalized relatives who were WS carriers (10/11) was much higher than expected (3.1/11), leading to the provisional estimate that WS gene carriers are 26-fold more likely to require psychiatric hospitalization than non-carriers.
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Peña A, Guardino K, Tovilla JM, Levitt MA, Rodriguez G, Torres R. Bowel management for fecal incontinence in patients with anorectal malformations. J Pediatr Surg 1998; 33:133-7. [PMID: 9473119 DOI: 10.1016/s0022-3468(98)90380-3] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND/PURPOSE Fecal incontinence is common in patients operated on for anorectal malformations. Treatment with enemas, laxatives, and medications are often given by clinicians in an indiscriminate manner and without a demonstrated benefit. A systematic diagnostic approach and bowel management program was developed for patients suffering from fecal incontinence, and a retrospective analysis of the results is presented. METHODS Three hundred forty-eight patients were seen in consultation for fecal incontinence after repair of imperforate anus at other institutions. Clinical and radiological evaluation helped determine different types of patients. Group I consisted of 147 patients who were considered candidates for reoperation and forms the basis of a future report. Group II included 172 patients who had no potential for bowel control and were therefore candidates for bowel management. These patients fell into two categories; group IIA included 44 patients with incontinence and constipation. The bowel management involved the use of daily large enemas only. Group IIB included 128 patients with incontinence and a tendency to diarrhea. Group III consisted of 29 patients who had pseudoincontinence. They had an original defect with good prognosis, good sphincters, good sacrum, and a well-located rectum. They suffered from severe constipation, megasigmoid, chronic fecal impaction, and overflow pseudoincontinence and were treated with laxatives or sigmoid resection. RESULTS Bowel management was successful in 93% of patients in the constipation group (IIA) and 88% in the diarrhea group (IIB). Ninety-seven percent of patients in group III became fecally continent. CONCLUSION Bowel management consisting of enemas, laxatives, and medications is successful when administered in an organized manner. It is vital to determine the type of fecal incontinence from which the patients suffer and to target their treatment accordingly.
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Garces S, Torres R. [Public health as a subject for the Assembly]. CORREO POBLACIONAL Y DE LA SALUD 1997; 5:2-12. [PMID: 12178227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
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Becker KG, Lee IJ, Nagle JW, Canning RD, Gado AM, Torres R, Polymeropoulos MH, Massa PT, Biddison WE, Drew PD. C2H2-171: a novel human cDNA representing a developmentally regulated POZ domain/zinc finger protein preferentially expressed in brain. Int J Dev Neurosci 1997; 15:891-9. [PMID: 9568537 DOI: 10.1016/s0736-5748(97)00034-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
We describe a novel human zinc finger cNDA. C2H2-171. This cDNA represents an mRNA which encodes a protein of 484 amino acids and a calculated molecular weight of 54 kD. Four zinc finger-like domains are found in the C-terminal end of the protein. At the N-terminus, C2H2-171 contains a POZ/tramtrack-like domain similar to that found in the tumor associated zinc finger proteins LAZ-3/BCL-6 and PLZ-F, as well as in non-zinc finger proteins. C2H2-171 RNA is preferentially expressed in the brain, and increases during the course of murine development, with maximal expression in the adult. C2H2-171 RNA is differentially expressed in brain regions, with the highest level of expression in the cerebellum. C2H2-171 RNA was expressed at high levels in primary cerebellar granule cell neurons compared to astrocytes. The gene encoding C2H2-171 is highly conserved in vertebrates, and maps to the terminus of human chromosome 1 (1q44-ter). This chromosomal location is associated with a number of cytogenetic aberrations including those involving brain developmental anomalies and tumorigenesis. These data suggest that C2H2-171 may play an important role in vertebrate brain development and function.
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Torres R. [Official recognition of a social problem: maternal mortality in Ecuador]. CORREO POBLACIONAL Y DE LA SALUD 1997; 5:2-6. [PMID: 12178221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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