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1.
Int J Cardiol ; 322: 135-141, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-32798629

RESUMEN

BACKGROUND: The palliation of patients with single ventricle (SV) undergoing Fontan procedure led to improved long-term survival but is still limited due to cardiovascular complications. The aim of this study was to describe the somatic and cardiovascular development of Fontan patients until adolescence and to identify determining factors. METHODS: We retrospectively assessed somatic growth, vascular growth of pulmonary arteries, and cardiac growth of the SV and systemic semilunar valve from 0 to 16 years of age using transthoracic echocardiography. The Doppler inflow pattern of the atrioventricular valve was quantified by E-, A-wave and E/A ratio. All data were converted to z-scores and analyzed using linear mixed effect models to identify associations with age at Fontan procedure, gender, and ventricular morphology. RESULTS: 134 patients undergoing Fontan procedure at a median age of 2.4 (IQR 2.12 to 2.8) years were analyzed. A catch-up of somatic growth after Fontan procedure until school age was found, with lower body height and weight z-scores in male patients and patients with systemic right ventricles. An early time of Fontan procedure was favorable for somatic growth, but not for vascular growth. Cardiac development indicated a decrease of SV end-diastolic diameter z-score until adolescence. Despite a trend towards normalization, E-wave and E/A ratio z-scores were diminished over the entire period. CONCLUSIONS: There is a catch-up growth of somatic, vascular and cardiac parameters after Fontan procedure, which in our cohort depends on the time of Fontan procedure, ventricular morphology, and gender. Beside other factors, diastolic function of the SV remains altered.


Asunto(s)
Procedimiento de Fontan , Cardiopatías Congénitas , Corazón Univentricular , Adolescente , Preescolar , Procedimiento de Fontan/efectos adversos , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/cirugía , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/cirugía , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
2.
Geochem Geophys Geosyst ; 21(2): e2019GC008745, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32714098

RESUMEN

International Ocean Discovery Program Expeditions 352 and 351 drilled into the Western Pacific Izu-Bonin forearc and rear arc. The drill cores revealed that the forearc is composed of forearc basalts (FAB) and boninites and the rear arc consists of FAB-like rocks. These rocks are pervaded by calcite veins. Blocky vein microtextures enclosing host rock fragments dominate in all locations and suggest hydrofracturing and advective fluid flow. Significant diffusion-fed and crystallization pressure-driven antitaxial veining is restricted to the rear arc. The lack of faults and presence of an Eocene sedimentary cover in the rear arc facilitated antitaxial veining. Rare earth element and isotopic (δ18O, δ13C, 87Sr/86Sr, and Δ47) tracers indicate varying parental fluid compositions ranging from pristine to variably modified seawater. The most pristine seawater signatures are recorded by FAB-hosted low-T (<30 °C) vein calcites. Their 87Sr/86Sr ratios intersect the 87Sr/86Sr seawater curve at ~35-33 and ~22 Ma. These intersections are interpreted as precipitation ages, which concur with Pacific slab rollback. Boninite-hosted low-T (<30 °C) vein calcites precipitated from seawater that was modified by fluid-rock interactions. Mixing calculations yield a mixture of >95% seawater and <5% basaltic 87Sr/86Sr. In the rear arc, low-T rock alteration lowered the circulating seawater in δ18O and 87Sr/86Sr. Thus, vein calcites precipitated from modified seawater with up to 20-30% basaltic 87Sr/86Sr at temperatures up to 74 ± 12 °C. These results show how the local geology and vein growth dynamics affect microtextures and geochemical compositions of vein precipitates.

3.
J Interv Cardiol ; 2019: 6598637, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31772540

RESUMEN

OBJECTIVE: The aim of this study was to compare feasibility, effectiveness, safety, and outcome of atrial septal defect (ASD) device closure in children with and without fluoroscopy guidance. METHODS AND RESULTS: Children undergoing transcatheter ASD closure between 2002 and 2016 were included into this single center, retrospective study. Patients were analysed in two groups [1: intraprocedural fluoroscopy ± transoesophageal echocardiography (TOE) guidance; 2: TOE guidance alone]. Three-hundred-ninety-seven children were included, 238 (97 male) in group 1 and 159 (56 male) in group 2. Two-hundred-twenty-nine of 238 (96%) patients underwent successful fluoroscopy guided ASD closures versus 154/159 (97%) successful procedures with TOE guidance alone. Median weight (IQR) at intervention was 20kg (16.0-35.0) in group 1 versus 19.3kg (16.0-31.2) in group 2. Mean (SD) preinterventional ASD diameter was 12.4mm (4.4) in group 1 versus 12.2mm (3.9) in group 2. There was no significant difference in number of defects or characteristics of ASD rims. Median procedure time was shorter in group 2 [60min (47-86) versus 34min (28-44)]. Device-size-to-defect-ratio was similar in both groups [group 1: 1.07 versus group 2: 1.09]. There were less technical intraprocedural events in group 2 [10 (6.3%) versus 47 (20%)]. Intraprocedural complications were less frequent in group 2 [1 (0.6%) versus 8 (3.3%)]. CONCLUSION: Transcatheter ASD device closure with TOE guidance alone (i.e., without fluoroscopy) is as effective and safe as ASD closure with fluoroscopy guidance. As fluoroscopy remains an important adjunct to transoesophageal echocardiography, especially in complex defects and complications, procedures are always performed in a fully equipped cardiac catheterization laboratory.


Asunto(s)
Defectos del Tabique Interatrial , Implantación de Prótesis , Dispositivo Oclusor Septal , Cirugía Asistida por Computador/métodos , Niño , Preescolar , Ecocardiografía Transesofágica/métodos , Estudios de Factibilidad , Femenino , Fluoroscopía/métodos , Defectos del Tabique Interatrial/diagnóstico por imagen , Defectos del Tabique Interatrial/epidemiología , Defectos del Tabique Interatrial/cirugía , Humanos , Masculino , Evaluación de Procesos y Resultados en Atención de Salud , Implantación de Prótesis/efectos adversos , Implantación de Prótesis/instrumentación , Implantación de Prótesis/métodos , Estudios Retrospectivos , Suiza/epidemiología
4.
Geochem Geophys Geosyst ; 20(12): 5867-5895, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32055237

RESUMEN

International Ocean Discovery Program Expedition 352 recovered sedimentary-volcaniclastic successions and extensional structures (faults and extensional veins) that allow the reconstruction of the Izu-Bonin forearc tectonic evolution using a combination of shipboard core data, seismic reflection images, and calcite vein microstructure analysis. The oldest recorded biostratigraphic ages within fault-bounded sedimentary basins (Late Eocene to Early Oligocene) imply a ~15 Ma hiatus between the formation of the igneous basement (52 to 50 Ma) and the onset of sedimentation. At the upslope sites (U1439 and U1442) extension led to the formation of asymmetric basins reflecting regional stretch of ~16-19% at strain rates of ~1.58 × 10-16 to 4.62 × 10-16 s-1. Downslope Site U1440 (closer to the trench) is characterized by a symmetric graben bounded by conjugate normal faults reflecting regional stretch of ~55% at strain rates of 4.40 × 10-16 to 1.43 × 10-15 s-1. Mean differential stresses are in the range of ~70-90 MPa. We infer that upper plate extension was triggered by incipient Pacific Plate rollback ~15 Ma after subduction initiation. Extension was accommodated by normal faulting with syntectonic sedimentation during Late Eocene to Early Oligocene times. Backarc extension was assisted by magmatism with related Shikoku and Parece-Vela Basin spreading at ~25 Ma, so that parts of the arc and rear arc, and the West Philippine backarc Basin were dismembered from the forearc. This was followed by slow-rift to postrift sedimentation during the transition from forearc to arc rifting to spreading within the Shikoku-Parece-Vela Basin system.

5.
Geochem Geophys Geosyst ; 20(12): 5913-5938, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32055238

RESUMEN

Calcite veins hosted in pillow lavas of the Late Cretaceous Troodos suprasubduction zone ophiolite provide insights into the timing and physicochemical environment of postmagmatic fracturing and fluid circulation through oceanic crust. This study presents rare earth element and yttrium (REE+Y) concentrations, δ13C, δ18O, 87Sr/86Sr, and clumped isotopic (Δ47) compositions of vein calcites in order to investigate their fluid sources, formation temperatures, and precipitation ages. These geochemical data are combined with microtextural analyses. Intersections of 87Sr/86Sr ratios of vein calcites with the Sr isotope seawater curve suggest two distinct calcite veining phases. Major calcite veining within an interval of ~10 Myr after crust formation is characterized by microtextures that point to extensional fracturing related to crack and sealing, host rock brecciation, and advective fluid flow. These vein calcites show REE+Y characteristics, 87Sr/86Sr ratios, and clumped isotopic compositions indicative of precipitation from seawater at <50 °C. Extended fluid residence times intensified fluid-rock interactions and lowered Y/Ho ratios of some blocky vein calcites, whereas crack and sealing resulted in pristine seawater signatures. Low 87Sr/86Sr ratios of localized high-temperature blocky vein calcites point to the involvement of hydrothermal fluids. These calcites show Mn-controlled oscillatory growth zonations that probably developed in a closed system out of equilibrium. Later calcite veining (<75 Ma) may have coincided with rotation and/or uplift of the Troodos ophiolite. Microtextures of these vein calcites indicate fluid diffusion and fracture-independent crystallization pressure-driven veining. Their variably modified seawater signatures resulted from diffusion-related fluid interaction with hydrothermal sediments.

6.
Opt Express ; 25(25): 31122-31129, 2017 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-29245789

RESUMEN

We report on the experimental demonstration of triggered single-photon emission at the telecom O-band from In(Ga)As/GaAs quantum dots (QDs) grown by metal-organic vapor-phase epitaxy. Micro-photoluminescence excitation experiments allowed us to identify the p-shell excitonic states in agreement with high excitation photoluminescence on the ensemble of QDs. Hereby we drive an O-band-emitting GaAs-based QD into the p-shell states to get a triggered single photon source of high purity. Applying pulsed p-shell resonant excitation results in strong suppression of multiphoton events evidenced by the as measured value of the second-order correlation function at zero delay of 0.03 (and ~0.005 after background correction).

7.
Genome ; 59(9): 661-70, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27314158

RESUMEN

Biodiversity loss is mainly driven by human activity. While concern grows over the fate of hot spots of biodiversity, contemporary species losses still prevail in industrialized nations. Therefore, strategies were formulated to halt or reverse the loss, driven by evidence for its value for ecosystem services. Maintenance of the latter through conservation depends on correctly identified species. To this aim, the German Federal Ministry of Education and Research is funding the GBOL project, a consortium of natural history collections, botanic gardens, and universities working on a barcode reference database for the country's fauna and flora. Several noticeable findings could be useful for future campaigns: (i) validating taxon lists to serve as a taxonomic backbone is time-consuming, but without alternative; (ii) offering financial incentives to taxonomic experts, often citizen scientists, is indispensable; (iii) completion of the libraries for widespread species enables analyses of environmental samples, but the process may not hold pace with technological advancements; (iv) discoveries of new species are among the best stories for the media; (v) a commitment to common data standards and repositories is needed, as well as transboundary cooperation between nations; (vi) after validation, all data should be published online via the BOLD to make them searchable for external users and to allow cross-checking with data from other countries.


Asunto(s)
Biodiversidad , Código de Barras del ADN Taxonómico , Bases de Datos Genéticas , Animales , Países Desarrollados , Alemania , Adhesión a Directriz , Humanos , Cooperación Internacional , Bibliotecas , Reproducibilidad de los Resultados
8.
Scand J Rheumatol ; 43(4): 307-13, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25088926

RESUMEN

OBJECTIVES: Programmed death (PD)-1 is a cell death receptor that, upon stimulation, leads to apoptosis. Previous studies have shown alteration of PD-1 expression on T cells and PD-1 genes in patients with systemic lupus erythematosus (SLE). The aim of this study was to assess the expression of this receptor on effector T cells in patients with SLE. METHOD: In this study we enrolled 32 SLE patients and 31 healthy controls. T cells from peripheral blood were analysed by flow cytometry for the expression of PD-1. Interferon (IFN)-γ and interleukin (IL)-17-producing cells were investigated for the expression of this co-stimulatory marker. RESULTS: Percentages of CD4(+) T cells expressing PD-1 were significantly increased in patients with SLE compared to healthy controls. The percentage of PD-1 expression was correlated with the production of INF-γ (r = 0.83, p < 0.0001). We also investigated the production of IL-17 by PD-1(+) CD3(+) T cells. Inactive patients (3.2 ± 1.2% vs. 5.9 ± 3.5%, p = 0.002) and patients without lupus nephritis (LN) (3.2 ± 1.5% vs. 5.9 ± 3.5%, p = 0.005) showed lower levels of IL-17 compared to healthy controls. CONCLUSION: We have demonstrated increased expression of PD-1 on CD4(+) T cells in SLE patients and an association between PD-1 expression on CD4(+) T cells and IFN-γ expression on CD3(+) T cells. We have also shown that there is an altered subset of PD-1(+) T cells in inactive patients and patients without LN producing lower amounts of IL-17.


Asunto(s)
Linfocitos T CD4-Positivos/metabolismo , Interferón gamma/metabolismo , Interleucina-17/metabolismo , Lupus Eritematoso Sistémico/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Adulto , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad
9.
Mol Phylogenet Evol ; 63(2): 351-64, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22266481

RESUMEN

Morphological characters from the gametophyte and sporophyte generations have been used in land plants to infer relationships and construct classifications, but sporophytes provide the vast majority of data for the systematics of vascular plants. In bryophytes both generations are well developed and characters from both are commonly used to classify these organisms. However, because morphological traits of gametophytes and sporophytes can have different genetic bases and experience different selective pressures, taxonomic emphasis on one generation or the other may yield incongruent classifications. The moss order Hookeriales has a controversial taxonomic history because previous classifications have focused almost exclusively on either gametophytes or sporophytes. The Hookeriales provide a model for comparing morphological evolution in gametophytes and sporophytes, and its impact on alternative classification systems. In this study we reconstruct relationships among mosses that are or have been included in the Hookeriales based on sequences from five gene regions, and reconstruct morphological evolution of six sporophyte and gametophyte traits that have been used to differentiate families and genera. We found that the Hookeriales, as currently circumscribed, are monophyletic and that both sporophyte and gametophyte characters are labile. We documented parallel changes and reversals in traits from both generations. This study addresses the general issue of morphological reversals to ancestral states, and resolves novel relationships in the Hookeriales.


Asunto(s)
Bryopsida/clasificación , Bryopsida/genética , Células Germinativas de las Plantas/fisiología , Filogenia , Secuencia de Bases , Evolución Biológica , Bryopsida/anatomía & histología , ADN de Plantas/genética , ADN Espaciador Ribosómico/genética , Evolución Molecular , Células Germinativas de las Plantas/clasificación , Mitocondrias/genética , Alineación de Secuencia , Análisis de Secuencia de ADN
10.
Pediatr Cardiol ; 32(4): 525-6, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21267717

RESUMEN

Pericarditis constrictiva is caused by fibrotic degeneration of the pericardium and leads to impaired diastolic ventricular filling. The diagnosis of constrictive pericarditis in children remains challenging and often requires a multimodal approach. We present a case of a pericarditis constrictiva in a 10-year old boy after influenza A virus infection. Clinicians should be aware of this complication, especially in patients with symptoms of exertional dyspnea and congestive heart failure.


Asunto(s)
Virus de la Influenza A , Gripe Humana/complicaciones , Pericarditis Constrictiva/etiología , Niño , Diagnóstico Diferencial , Ecocardiografía Doppler en Color , Estudios de Seguimiento , Humanos , Gripe Humana/virología , Imagen por Resonancia Cinemagnética , Masculino , Pericardiectomía/métodos , Pericarditis Constrictiva/diagnóstico , Pericarditis Constrictiva/cirugía
11.
Mol Phylogenet Evol ; 46(3): 863-77, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18262799

RESUMEN

Phylogenetic relationships within the Grimmiaceae/Ptychomitriaceae were studied using a plastid tRNA cluster, including four tRNAs (trnS, trnT, trnL, trnF), a fast evolving gene (rps4), four spacers separating the coding regions, as well as one group I intron. Secondary structure analyses of the spacers as well as the trnL intron P8 domain identified several homoplastic inversions. Tracing the structural evolution of P8 we were able to identify lineage specific modifications that are mainly explained by inversions often in combination with large indel events. Phylogenetic analyses using maximum parsimony, maximum likelihood, and Bayesian methods indicate that Jaffueliobryum and Indusiella are closely related to Ptychomitrium and form the Ptychomitriaceae s. str. As Campylostelium is neither resolved within Ptychomitriaceae s. str. nor Grimmiaceae s. str., we prefer to treat it in its own family, Campylosteliaceae De Not. The systematic position of Glyphomitrium, as also found by other authors, should be considered in a broader analysis of haplolepidous mosses as our analyses indicate that it is not part of Campylosteliaceae, Grimmiaceae, or Ptychomitriaceae. Within Grimmiaceae s. str., Racomitrium is recognized as a monophyletic group sister to a clade including Dryptodon, Grimmia, and Schistidium. Coscinodon species appear disperse in Grimmia s. str. next to species sharing the same gametophyte morphology, and thus the genus is synonymized with Grimmia. Finally, Schistidium is resolved monophyletic with high statistical support, and seems to represent a rapidly evolving group of species. Our results are not fully congruent with recently published treatments splitting Grimmiaceae in a fairly high number of genera, neither with a comprehensive Grimmia including Dryptodon and Grimmia s. str.


Asunto(s)
Briófitas/genética , ADN de Cloroplastos/genética , Filogenia , Secuencia de Bases , Teorema de Bayes , Briófitas/clasificación , ADN de Cloroplastos/química , Evolución Molecular , Funciones de Verosimilitud , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , ARN de Transferencia/química , ARN de Transferencia/genética , Análisis de Secuencia de ADN
12.
Theor Appl Genet ; 111(7): 1229-37, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16187123

RESUMEN

Section Arachis is the largest of nine sections in the genus Arachis and includes domesticated peanut, A. hypogaea L. Most species are diploids (x = 10) with two tetraploids and a few aneuploids. Three genome types have been recognized in this section (A, B and D), but the genomes are not well characterized and relationships of several newly described species are uncertain. To clarify genomic relationships in section Arachis, cytogenetic information and molecular data from amplified fragment length polymorphism (AFLP) and the trnT-F plastid region were used to provide an additional insight into genome composition and species relationships. Cytogenetic information supports earlier observations on genome types of A. cruziana, A. herzogii, A. kempff-mercadoi and A. kuhlmannii but was inconclusive about the genome composition of A. benensis, A. hoehnei, A. ipaensis, A. palustris, A. praecox and A. williamsii. An AFLP dendrogram resolved species into four major clusters and showed A. hypogaea grouping closely with A. ipaensis and A. williamsii. Sequence data of the trnT-F region provided genome-specific information and showed for the first time that the B and D genomes are more closely related to each other than to the A genome. Integration of information from cytogenetics and biparentally and maternally inherited genomic regions show promise in understanding genome types and relationships in Arachis.


Asunto(s)
Arachis/genética , Genes de Plantas/genética , Genoma de Planta/genética , Filogenia , Arachis/clasificación , Secuencia de Bases , Análisis por Conglomerados , Cruzamientos Genéticos , Análisis Citogenético , Funciones de Verosimilitud , Modelos Genéticos , Datos de Secuencia Molecular , Técnicas de Amplificación de Ácido Nucleico , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN
13.
Plant Biol (Stuttg) ; 6(5): 545-54, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15375725

RESUMEN

Structure, variability, and molecular evolution of the trnT-F region in the Bryophyta (mosses and liverworts) is analyzed based on about 200 sequences of the trnT-L spacer and trnL 5' exon, 1000 sequences of the trnL intron, and 800 sequences of the trnL 3' exon and trnL-F spacer, including comparisons of lengths, GC contents, sequence similarities, and functional elements. Mutations occurring in the trnL 5' and 3' exons, including compensatory base pair changes, and a transition in the trnL anticodon in Takakia lepidozioides, are discussed. All three non-coding regions display a mosaic structure of highly variable elements (V1 - V3 in the trnT-L spacer, V4/V5 corresponding to stem-loop regions P6/P8 in the trnL intron, and V6/V7 in the trnL-F spacer) and more conserved elements. In the trnL intron this structure is a consequence of the defined secondary structure necessary for correct splicing, whereas in both spacers conserved regions are restricted to promoter elements. At least the highly variable regions in the trnT-L spacer and stem-loop region P8 of the trnL intron seem to evolve independently in the major bryophyte lineages and are therefore not suitable for high taxonomic level phylogenetic reconstructions. In mosses, a trend of length reduction towards the more derived lineages is observed in all three non-coding regions. GC contents are mostly linked to sequence variability, with the conserved regions being more GC rich and the more variable AT rich. The lowest GC values (< 10 %) are found in the trnT-L spacer of mosses. In addition to two putative sigma (70)-type promoters in the trnT-L spacer, a third putative promoter is present in the trnL-F spacer, although trnL and trnF are assumed to be co-transcribed. Consensus sequences are provided for the -35 and -10 sequences of the major bryophyte lineages. The third promoter is part of a hairpin secondary structure, whose loop region is highly homoplastic in mosses due to an inversion occurring independently in non-related taxa, even at the intraspecific level.


Asunto(s)
Briófitas/genética , ARN del Cloroplasto/genética , ARN de Transferencia Aminoácido-Específico/genética , Secuencia de Bases , Secuencia Conservada , ADN de Cloroplastos/química , ADN de Cloroplastos/genética , ADN Intergénico/química , ADN Intergénico/genética , Evolución Molecular , Exones , Genes de Plantas , Intrones , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , ARN del Cloroplasto/química , ARN de Transferencia Aminoácido-Específico/química , ARN de Transferencia de Leucina/química , ARN de Transferencia de Leucina/genética
14.
J Evol Biol ; 16(4): 558-76, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-14632220

RESUMEN

Recent contributions from DNA sequences have revolutionized our concept of systematic relationships in angiosperms. However, parts of the angiosperm tree remain unclear. Previous studies have been based on coding or rDNA regions of relatively conserved genes. A phylogeny for basal angiosperms based on noncoding, fast-evolving sequences of the chloroplast genome region trnT-trnF is presented. The recognition of simple direct repeats allowed a robust alignment. Mutational hot spots appear to be confined to certain sectors, as in two stem-loop regions of the trnL intron secondary structure. Our highly resolved and well-supported phylogeny depicts the New Caledonian Amborella as the sister to all other angiosperms, followed by Nymphaeaceae and an Austrobaileya-Illicium-Schisandra clade. Ceratophyllum is substantiated as a close relative of monocots, as is a monophyletic eumagnoliid clade consisting of Piperales plus Winterales sister to Laurales plus Magnoliales. Possible reasons for the striking congruence between the trnT-trnF based phylogeny and phylogenies generated from combined multi-gene, multi-genome data are discussed.


Asunto(s)
ADN de Cloroplastos/genética , Magnoliopsida/genética , Filogenia , Secuencia de Bases , Evolución Molecular , Datos de Secuencia Molecular , ARN de Transferencia , Análisis de Secuencia de ADN
15.
J Nutr Biochem ; 12(1): 46-54, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11179861

RESUMEN

The objective of this study was to determine the effects of diazepam, L-alanyl-L-glutamine (ala-gln) or diazepam combined with ala-gln on polymorphonuclear leukocyte (PMN) free amino acid profiles. In a parallel study the effects on PMN immune functions were also documented for the first time. The incubation of whole blood with diazepam led to significant changes in PMN free glutamine, aspartate, glutamate, ornithine, arginine, citrulline, taurine and methionine as well as branched chain and neutral amino acid concentrations. Ala-gln caused significant increases in PMN glutamine and alanine and asparagine, aspartate, glutamate, ornithine, arginine, serine and glycine profiles. Regarding PMN immune functions, diazepam significantly decreased superoxide anion (O(2)(-)) and hydrogen peroxide production (H(2)O(2)) and myeloperoxidase activity (MPO) while ala-gln significantly increased PMN immune functions. Ala-gln supplemented to diazepam largely reversed the changes in PMN amino acid profiles and PMN immune functions brought about by diazepam. Overall, diazepam or ala-gln lead to significant changes in PMN free amino acids. Important PMN immune functions also seem to be affected. In regards to the results, there is significant relevance to the pharmacological regimens which enhance the supply of diazepam or ala-gln in whole blood suggesting that considerable changes in PMN "labile free amino acid pool" occur. These regimens often follow beneficial nutritional therapy or maleficent pharmacological stress and may be one of the determinants in cell nutrition which influence PMN function. It is partially through its effect on PMN labile free amino acid pool that ala-gln supplemented to diazepam may maintain PMN immune functions in vitro.

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