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1.
Sci Total Environ ; 811: 152380, 2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-34914978

RESUMEN

Exchange between groundwater (GW), hyporheic zone waters (HZ) and surface waters (SW) is critical for water quality, quantity, and the ecological health and functioning of all three ecosystems. Hydrological exchange is particularly important in intermittent creeks, such as in the Murray Darling Basin, Australia, where stream reaches shift from losing to gaining depending on the volume of surface flows. In this study we used hydrochemistry to identify SW-GW exchange and combined this with eDNA data to analyse the response of eukaryote and prokaryote communities to differing flow conditions within intermittent and perennial stream reaches. Our study suggested that SW and GW microbial communities were only around 30% similar. Differences in microbiota between SW, HZ and GW habitats were driven by changes in relative abundances of surface water dominant organisms (such as those capable of photosynthesis) as well as anaerobic taxa typical of GW environments (e.g., methanogens), with GW and HZ microbial communities becoming increasingly different to those in SW as flow ceased in intermittent creeks. Fine-scale hydrologic changes were identified through microbial communities in the perennial Maules Creek, indicating the importance of GW-SW exchange to biotic communities. This study highlights the importance of flow in shaping microbial communities and biogeochemical cycling within intermittent creeks and their connected alluvial aquifers. Our results suggest that microbiota may prove a useful indicator of SW-GW exchange, and in some circumstances, may be more sensitive in demonstrating fine-scale changes in SW-GW interactions than water chemistry. This knowledge furthers our understanding of GW-SW exchange and its impacts on ecological health.


Asunto(s)
Agua Subterránea , Microbiota , Australia , Hidrología , Ríos
2.
Eur J Pediatr Surg ; 29(1): 33-38, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30112743

RESUMEN

INTRODUCTION: Surgery for ureteropelvic junction obstruction (UPJO) is performed by both pediatric surgeons (PS) and urologists (URO). The aim of this study was to analyze treatment modalities for UPJO and results in relation to the surgical technique and the operating discipline in Germany. MATERIALS AND METHODS: Data of patients aged 0 to 18 years were extracted from a major public health insurance (covering ∼5.7 million clients) during 2009 to 2016 and were analyzed for sociodemographic variables, surgical technique, and treating discipline. Logistic regression analysis was performed for the risk of a complication within the first postoperative year. RESULTS: A total of 229 children (31.0% female) were included. Laparoscopic pyeloplasty (LP) was performed in 58 (25.3%) patients (8.6 ± 6.4 years), and open pyeloplasty (OP) was applied in 171 (74.7%; 4.6 ± 5.9 years). LP was the dominant technique in females (p < 0.02); males preferentially underwent OP (p < 0.02). Length of hospital stay was 4.3 days (p = 0.0005) shorter in LP compared with that in OP, especially in children ≤ 2 years (6.7 days, p = 0.007). PS operated on 162 children (70.7%), and URO performed surgery on 67 patients (29.3%). The mean age of children operated by PS (3.5 ± 4.7 years) was significantly younger compared with that operated by URO (10.8 ± 6.5 years, p < 0.0001). Complication rates were independent of surgical technique or treating specialty. CONCLUSION: In Germany, UPJO was treated by LP in 25.3% of patients, which was associated with a shorter length of stay, especially in children ≤ 2 years. Complication rates were independent of the operating specialty and surgical technique. Therefore, LP should be further promoted for the treatment of UPJO in small children.


Asunto(s)
Pelvis Renal/cirugía , Pautas de la Práctica en Medicina , Obstrucción Ureteral/cirugía , Procedimientos Quirúrgicos Urológicos/métodos , Adolescente , Niño , Preescolar , Femenino , Alemania , Humanos , Lactante , Recién Nacido , Laparoscopía/efectos adversos , Tiempo de Internación , Masculino , Pediatras , Complicaciones Posoperatorias , Estudios Retrospectivos , Cirujanos , Resultado del Tratamiento , Procedimientos Quirúrgicos Urológicos/efectos adversos , Urólogos
3.
Clin Res Cardiol ; 107(6): 487-497, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29404680

RESUMEN

BACKGROUND: Heart failure (HF) with reduced ejection fraction (HFrEF) has a worse prognosis than HF with preserved EF (HFpEF). The study aimed to evaluate whether different comorbidity profiles of HFrEF- and HFpEF-patients or HF-specific mechanisms contribute to a greater extent to this difference. METHODS: We linked data from two health insurances to data from a cardiology clinic hospital information system. Patients with a hospitalization with HF in 2005-2011, categorized as HFrEF (EF < 45%) or HFpEF (EF ≥ 45%), were propensity score (PS) matched to controls without HF on comorbidites and medication to assure similar comorbidity profiles of patients and their respective controls. The balance of the covariates in patients and controls was compared via the standardized difference (SDiff). Age-standardized 1-year mortality rates (MR) with 95% confidence intervals (CI) were calculated. RESULTS: 777 HFrEF-patients (1135 HFpEF-patients) were PS-matched to 3446 (4832) controls. Balance between patients and controls was largely achieved with a SDiff < 0.1 on most variables considered. The age-standardized 1-year MRs per 1000 persons in HFrEF-patients and controls were 267.8 (95% CI 175.9-359.8) and 86.1 (95% CI 70.0-102.3). MRs in HFpEF-patients and controls were 166.2 (95% CI 101.5-230.9) and 61.5 (95% CI 52.9-70.1). Thus, differences in MRs between patients and their controls were higher for HFrEF (181.7) than for HFpEF (104.7). CONCLUSIONS: Given the similar comorbidity profiles between HF-patients and controls, the higher difference in mortality rates between HFrEF-patients and controls points more to HF-specific mechanisms for these patients, whereas for HFpEF-patients a higher contribution of comorbidity is suggested by our results.


Asunto(s)
Insuficiencia Cardíaca/epidemiología , Pacientes Internos , Puntaje de Propensión , Volumen Sistólico/fisiología , Disfunción Ventricular Izquierda/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Comorbilidad/tendencias , Ecocardiografía , Femenino , Estudios de Seguimiento , Alemania/epidemiología , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Disfunción Ventricular Izquierda/diagnóstico , Disfunción Ventricular Izquierda/fisiopatología , Adulto Joven
4.
Artículo en Alemán | MEDLINE | ID: mdl-23334292

RESUMEN

Using data obtained from a statutory health insurance (AOK) in the federal state of Lower Saxony, this study examined whether there were differences between the insured population compared with that of Lower Saxony (Niedersachsen) and of Germany with respect to social structural characteristics. Data for the comparisons were provided by the statistical office of Germany, and all datasets were coded according to the same criteria. The differences in gender distribution and age distribution between the AOK, Lower Saxony, and Germany were small. The share of employed individuals among the insured compared with those of Lower Saxony and Germany did not differ for males, but it was lower in women. In the insured population a higher proportion of individuals had lower qualification levels than in Lower Saxony or in Germany; the number of individuals with higher qualifications was, however, sufficient to permit statistical analyses. There were differences in the distributions of social structural characteristics between the health insurance population on the one hand and the populations of Lower Saxony and of Germany on the other. Due to the high number of cases, it is nevertheless possible to analyze associations between social structural variables, health impairments, and patterns of health care utilization.


Asunto(s)
Estado de Salud , Programas Nacionales de Salud/estadística & datos numéricos , Asignación de Recursos/estadística & datos numéricos , Revisión de Utilización de Recursos , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Alemania/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Distribución por Sexo , Factores Socioeconómicos , Adulto Joven
5.
Schmerz ; 23(1): 47-53, 2009 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-19050936

RESUMEN

BACKGROUND: The dimensions of orally administered pharmacological placebos in routine clinical practice and the attitude of the clinical staff towards placebos are widely unknown. The aim of this report was to examine the frequency, indications and the intentions of placebo use at the Medical University of Hannover (MHH). METHODS: This study was performed as an anonymous cross-sectional written survey at the MHH. Quantitative data on placebo requests registered by the dispensary were obtained in advance. RESULTS: A total of 74% of respondents reported using placebos in clinical practice, including 53% of physicians and 88% of the nursing staff. Pain (76%) and insomnia (59%) were the most frequently reported reasons for administering placebos. Placebos were considered to be highly effective by 28.5% of physicians and 63.8% of the nursing staff. CONCLUSION: The effective use of pharmacological placebos appears to be an established component of the therapeutic options of a tertiary referral center. The placebo effect seems to contain remarkable potential. While the use of pharmacological placebos is ethically problematic within the clinical context, the improvement of caregiver-patient interactions and the utilization of positive suggestion could serve as an ideal adjunct to active therapy regimes.


Asunto(s)
Centros Médicos Académicos , Actitud del Personal de Salud , Depresión/tratamiento farmacológico , Dispepsia/tratamiento farmacológico , Dolor/tratamiento farmacológico , Placebos/uso terapéutico , Trastornos del Inicio y del Mantenimiento del Sueño/tratamiento farmacológico , Adulto , Estudios Transversales , Recolección de Datos , Ética Médica , Ética en Enfermería , Femenino , Alemania , Humanos , Masculino , Cuerpo Médico de Hospitales/ética , Persona de Mediana Edad , Personal de Enfermería en Hospital/ética , Derivación y Consulta , Resultado del Tratamiento , Adulto Joven
6.
J Insect Physiol ; 53(2): 126-31, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17210163

RESUMEN

Butterflies of the genus Heliconius are well known for their peculiar habits of utilizing pollen as a source of amino acids. Saliva plays a major role in the process of extracting amino acids and proteins from the pollen grains. In this investigation, we obtained samples of saliva from adult Heliconius melpomene by placing pumpkin pollen or fine glass-beads on the proboscis, which stimulates the butterflies to release saliva. Proteolytic activity was determined in the saliva by an insoluble protein-dye that turns blue when cleaved by proteases. Its extinction value was measured with a spectrophotometer at 595 nm. Both the saliva sampled with pollen and the saliva obtained from inert glass-beads exhibit proteolytic activity demonstrating that the saliva contains proteases. The proteolytic activity of the pollen/saliva samples was higher than that of the glass-bead/saliva samples, which we attribute to the stimulating effects of pollen, such as taste, smell, and texture, and not to proteases which might have been liberated from the pollen. This is indicated by the fact that pollen samples without saliva showed only a negligible indication for proteolytic activity. In general, females exhibit higher proteolytic activities than males, presumably due to their greater amino acid investment in reproduction. We present here first evidence for the existence of proteases in the saliva of a butterfly species and suggest that these enzymes are crucial for the use of amino acids and proteins from pollen in Heliconius butterflies.


Asunto(s)
Mariposas Diurnas/enzimología , Péptido Hidrolasas/análisis , Saliva/enzimología , Animales , Femenino , Masculino , Factores Sexuales , Espectrofotometría , Estadísticas no Paramétricas
7.
Mol Ecol ; 16(2): 355-65, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17217350

RESUMEN

The landscape of the Pilbara region of Western Australia has been relatively unchanged for 100 million years. The ancient river systems of this region might be expected to be sources of isolation and divergence for aquatic species. Hence, the occurrence of widespread groundwater taxa in this landscape offers the opportunity to examine associations between genetic diversity and drainage patterns. Pilbarus and Chydaekata are two widespread genera of subterranean amphipods endemic to the Pilbara, each occupying multiple tributaries. We used molecular data to examine the roles of drainage patterns in structuring genetic diversity. Gene flow within a tributary may be facilitated by the occasional occurrence of these amphipods in springs, which results in their downstream dispersal during episodic flooding. However, tributary boundaries may form hydrological barriers to gene flow, resulting in localised isolation of populations and divergence. Samples of both genera, collected throughout three river basins, were examined for sequence divergence in the cytochrome c oxidase I mitochondrial gene. There was no evidence of contemporary gene flow among populations of either genus, and each tributary contained highly divergent lineages, which were not associated with similar morphological differentiation. This suggests cryptic speciation has occurred, and similar phylogenetic signals in both taxa imply similar evolutionary histories. Surface populations may have been driven into subterranean refugia by the cessation of flow in the rivers, associated with Tertiary climate change, while morphological evolution may have been constrained by stabilising selection. The lack of congruence between molecular diversity and morphology raises important practical issues for conservation.


Asunto(s)
Anfípodos/genética , Demografía , Ambiente , Especiación Genética , Variación Genética , Filogenia , Animales , Secuencia de Bases , Teorema de Bayes , Cartilla de ADN , ADN Mitocondrial/genética , Evolución Molecular , Flujo Génico/genética , Geografía , Haplotipos/genética , Funciones de Verosimilitud , Modelos Genéticos , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Australia Occidental
8.
Biomed Tech (Berl) ; 47 Suppl 1 Pt 2: 708-11, 2002.
Artículo en Alemán | MEDLINE | ID: mdl-12465280

RESUMEN

Treadmill training with partial body weight support was shown to significantly improve the constitution and gait capacity of incomplete spinal cord injured (SCI) persons. The main requirement for application of this therapy is a sufficient capacity of the cardiovascular system. Most of the SCI patients do not comply with this requirement in the first few weeks after spinal cord injury, where spinal reflexes are frequently missing (spinal shock). To offer SCI patients a locomotion therapy at this early stage of rehabilitation we developed a novel, active tilt-table, the Reha-Stepper, that moves the lower limbs in an almost physiological manner in terms of kinematic and kinetic parameters. The tilt of the device can be continuously increased from horizontal to almost upright position adapted to the status of the patient.


Asunto(s)
Paraplejía/rehabilitación , Modalidades de Fisioterapia/instrumentación , Traumatismos de la Médula Espinal/rehabilitación , Terapia Asistida por Computador/instrumentación , Caminata/fisiología , Fenómenos Biomecánicos , Humanos , Paraplejía/fisiopatología , Postura/fisiología , Programas Informáticos
9.
Science ; 294(5543): 846-9, 2001 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-11679668

RESUMEN

Turgor-driven plant cell growth depends on wall structure. Two allelic l-fucose-deficient Arabidopsis thaliana mutants (mur1-1 and 1-2) are dwarfed and their rosette leaves do not grow normally. mur1 leaf cell walls contain normal amounts of the cell wall pectic polysaccharide rhamnogalacturonan II (RG-II), but only half exists as a borate cross-linked dimer. The altered structure of mur1 RG-II reduces the rate of formation and stability of this cross-link. Exogenous aqueous borate rescues the defect. The reduced cross-linking of RG-II in dwarf mur1 plants indicates that plant growth depends on wall pectic polysaccharide organization.


Asunto(s)
Arabidopsis/crecimiento & desarrollo , Boratos/metabolismo , Pared Celular/química , Glucanos , Pectinas/química , Pectinas/metabolismo , Xilanos , Alelos , Arabidopsis/química , Arabidopsis/genética , Arabidopsis/metabolismo , Boratos/farmacología , Conformación de Carbohidratos , Secuencia de Carbohidratos , Pared Celular/metabolismo , Pared Celular/ultraestructura , Dimerización , Fucosa/análisis , Fucosa/metabolismo , Fucosa/farmacología , Genes de Plantas , Hidroliasas/genética , Hidroliasas/metabolismo , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Mutación , Hojas de la Planta/química , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Polisacáridos/química , Polisacáridos/metabolismo
10.
Mol Genet Genomics ; 265(1): 32-42, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11370870

RESUMEN

Tissue culture has been shown to induce the transposition of plant transposable elements; their insertion at novel sites results in somaclonal variation. Introduction of the tobacco retrotransposon Tnt1 into Arabidopsis thaliana by co-cultivation of root explants with Agrobacterium tumefaciens induces its transposition at a high frequency, but no transposed copies are found in plants transformed by the in planta procedure. Transposition occurs in the transformed root cells or in the calli derived from them, allowing the regeneration of transformed plants with up to 26 transposed copies of Tnt1. Analysis of Tnt1 integration sites in Arabidopsis shows that the Tnt1 endonuclease does not show any cleavage-site specificity at the sequence level. The insertion sites are unlinked and distributed on all five Arabidopsis chromosomes. The fact that the majority of the integration sites are located in coding regions, and none in repeated sequences, demonstrates the potential of Tnt1 as a tool for gene tagging.


Asunto(s)
Agrobacterium tumefaciens/genética , Arabidopsis/genética , Genoma de Planta , Retroelementos , Arabidopsis/metabolismo , Southern Blotting , Secuencia de Consenso , ADN de Plantas/análisis , Mutagénesis Insercional , Raíces de Plantas/citología , Raíces de Plantas/genética , Plantas Modificadas Genéticamente/citología , Plantas Modificadas Genéticamente/genética , Reacción en Cadena de la Polimerasa , Transformación Genética
11.
J Invest Dermatol ; 116(1): 62-8, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11168799

RESUMEN

Chronic exposure to ultraviolet radiation suppresses T cell-mediated immune responses and induces the formation of suppressor T lymphocytes that prevent the rejection of highly antigenic ultraviolet-induced skin cancers in mice. Tamarind seed xyloglucans and pectinic oligogalacturonides prevent suppression of delayed-type hypersensitivity immune responses in mice to Candida albicans and alloantigen caused by a single exposure of ultraviolet radiation. We therefore investigated the ability of these poly/oligosaccharides to prevent suppression of T cell-mediated immune responses and suppressor cell induction during chronic ultraviolet irradiation and to preserve the capacity of ultraviolet-irradiated mice to reject a transplanted, highly antigenic, ultraviolet-induced tumor. C3H/HeN mice were treated 3x per week for 12 wk with 15 kJ per m2 ultraviolet B radiation followed by application of the polysaccharides/ oligosaccharides. The delayed-type hypersensitivity responses to C. albicans and alloantigen were measured after 1, 6, and 12 wk of treatment. Following the 12th wk of treatment the remaining mice were injected with the highly antigenic ultraviolet-induced, syngeneic tumor cell line UV5497-5. The polysaccharides/oligosaccharides protected delayed-type hypersensitivity responses to C. albicans but not contact hypersensitivity responses to dinitrofluorobenzene for up to 6 wk of ultraviolet radiation after which protection declined and suppressor cells were observed. In contrast, the delayed-type hypersensitivity response to alloantigen was preserved for the entire 12 wk of ultraviolet irradiation. Despite protection of immunity to alloantigen, the transplanted tumor cells grew equally well in all ultraviolet-irradiated animals. These results indicate that delayed-type hypersensitivity responses are heterogeneous and that delayed-type hypersensitivity to alloantigen is not a surrogate marker for rejection of ultraviolet-induced skin tumors.


Asunto(s)
Glucanos , Ácidos Hexurónicos/inmunología , Hipersensibilidad Tardía/inmunología , Isoantígenos/inmunología , Oligosacáridos/inmunología , Polisacáridos/inmunología , Neoplasias Cutáneas/prevención & control , Rayos Ultravioleta/efectos adversos , Xilanos , Animales , Dermatitis por Contacto/prevención & control , Femenino , Ácidos Hexurónicos/farmacología , Tolerancia Inmunológica/efectos de la radiación , Isoantígenos/uso terapéutico , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Oligosacáridos/farmacología , Polisacáridos/farmacología , Neoplasias Cutáneas/etiología , Linfocitos T Reguladores/efectos de los fármacos
12.
Planta ; 214(1): 67-74, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11762172

RESUMEN

Mutation of the Arabidopsis thaliana (L.) Heynh. gene MUR1, which encodes an isoform of GDP-D-mannose-4,6-dehydratase, affects the biosynthetic conversion of GDP-mannose to GDP-fucose. Cell walls in the aerial tissues of mur1 plants are almost devoid of alpha-L-fucosyl residues, which are partially replaced by closely related alpha-L-galactosyl residues. A line of suspension-cultured A. thaliana cells was generated from leaves of mur1 plants and the structure of the xyloglucan in the walls of these cells was structurally characterized. Xyloglucan fractions were prepared from the walls of both wild-type (WT) and mur1 cells by sequential extraction with a xyloglucan-specific endoglucanase (XEG) and aqueous KOH. Structural analysis of these fractions revealed that xyloglucan produced by cultured mur1 cells is similar, but not identical to that isolated from leaves of mur1 plants. As previously reported for mur1 leaves, the xyloglucan from cultured mur1 cells contains less than 5% of the fucose present in the xyloglucan from WT cells. Fucosylation of the xyloglucan is substantially restored when mur1 cells are grown in medium supplemented with L-fucose. Xyloglucan isolated from leaves contains more oligosaccharide subunits in which the central sidechain is terminated with a beta-D-galactosyl residue than does xyloglucan prepared from cultured cells. This was observed for both mur1 and WT plants, indicating that this correlation is independent of the mur1 mutation and that it is possible to distinguish changes due to genetic mutation from those due to the physiological state of the cells in culture. Suspension-cultured cells thus provide a convenient source of genetically altered cell wall material, facilitating the biochemical characterization of mutations that affect cell wall structure.


Asunto(s)
Arabidopsis/metabolismo , Proteínas Bacterianas , Glucanos , Muramidasa/metabolismo , Hojas de la Planta/metabolismo , Polisacáridos/biosíntesis , Xilanos , Arabidopsis/citología , Secuencia de Carbohidratos , Pared Celular/metabolismo , Células Cultivadas , Oscuridad , Luz , Datos de Secuencia Molecular , Muramidasa/genética , Mutación , Hojas de la Planta/citología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
13.
Praxis (Bern 1994) ; 88(17): 772-4, 1999 Apr 22.
Artículo en Alemán | MEDLINE | ID: mdl-10373791

RESUMEN

A 85 year old female was hospitalized because of a bronchopulmonary infection. During the hospitalization she developed a progressive stupor. There was no sign of an intracerebral pathology, an electrolyte disorder, a new infection or a psychiatric diagnosis. Evaluation of the past history made a recently started digitalis medication responsible for the stupor. After discontinuation of digitalis the patient regained complete consciousness within two weeks. In the Holter-EKG we found once an asystole of four seconds duration without any symptoms.


Asunto(s)
Astenia/inducido químicamente , Astenia/diagnóstico , Digitalis/efectos adversos , Plantas Medicinales , Plantas Tóxicas , Intoxicación/diagnóstico , Intoxicación/psicología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Motivación
14.
Photochem Photobiol ; 69(2): 141-7, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10048309

RESUMEN

Application of Aloe barbadensis poly/oligosaccharides to UV-irradiated skin prevents photosuppression of delayed-type hypersensitivity (DTH) responses in mice. We tested the hypothesis that these carbohydrates belong to a family of biologically active, plant-derived polysaccharides that can regulate responses to injury in animal tissues. C3H mice were exposed to 5 kJ/m2 UVB from unfiltered FS40 sunlamps and treated with between 1 pg and 10 micrograms tamarind xyloglucans or control polysaccharides methylcellulose or dextran in saline. The mice were sensitized 3 days later with Candida albicans. Tamarind xyloglucans and purified Aloe poly/oligosaccharides prevented suppression of DTH responses in vivo and reduced the amount of interleukin (IL)-10 observed in UV-irradiated murine epidermis. Tamarind xyloglucans were immunoprotective at low picogram doses. In contrast, the control polysaccharides methylcellulose and dextran had no effect on immune suppression or cutaneous IL-10 at any dose. Tamarind xyloglucans and Aloe poly/oligosaccharides also prevented suppression of immune responses to alloantigen in mice exposed to 30 kJ/m2 UVB radiation. To assess the effect of the carbohydrates on keratinocytes, murine Pam212 cells were exposed to 300 J/m2 UVB radiation and treated for 1 h with tamarind xyloglucans or Aloe poly/oligosaccharides. Treatment of keratinocytes with immunoprotective carbohydrates reduced IL-10 production by approximately 50% compared with the cells treated with UV radiation alone and completely blocked suppressive activity of the culture supernatants in vivo. The tamarind xyloglucans also blocked UV-activated phosphorylation of SAPK/JNK protein but had no effect on p38 phosphorylation. These results indicate that animals, like plants, may use carbohydrates to regulate responses to environmental stimuli.


Asunto(s)
Glucanos , Interleucina-1/biosíntesis , Proteínas Quinasas Activadas por Mitógenos , Plantas Medicinales , Polisacáridos/farmacología , Linfocitos T/inmunología , Rayos Ultravioleta , Xilanos , Administración Tópica , Aloe , Animales , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Secuencia de Carbohidratos , Femenino , Hipersensibilidad Tardía/inmunología , Proteínas Quinasas JNK Activadas por Mitógenos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Datos de Secuencia Molecular , Semillas , Piel/efectos de los fármacos , Piel/efectos de la radiación , Linfocitos T/efectos de los fármacos , Linfocitos T/efectos de la radiación , Proteínas Quinasas p38 Activadas por Mitógenos
15.
Plant Physiol ; 116(4): 1289-98, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9536045

RESUMEN

The biological activity of reducing-end-modified oligogalacturonides was quantified in four tobacco (Nicotiana tabacum) tissue culture bioassays. The derivatives used were oligogalacturonides with the C-1 of their reducing end (a) covalently linked to a biotin hydrazide, (b) covalently linked to tyramine, (c) chemically reduced to a primary alcohol, or (d) enzymatically oxidized to a carboxylic acid. These derivatives were tested for their ability to (a) alter morphogenesis of N. tabacum cv Samsun thin cell-layer explants, (b) elicit extracellular alkalinization by suspension-cultured cv Samsun cells, (c) elicit extracellular alkalinization by suspension-cultured N. tabacum cv Xanthi cells, and (d) elicit H2O2 accumulation in the cv Xanthi cells. In all four bioassays, each of the derivatives had reduced biological activity compared with the corresponding underivatized oligogalacturonides, demonstrating that the reducing end is a key element for the recognition of oligogalacturonides in these systems. However, the degree of reduction in biological activity depends on the tissue culture system used and on the nature of the specific reducing-end modification. These results suggest that oligogalacturonides are perceived differently in each tissue culture system.


Asunto(s)
Ácidos Hexurónicos/metabolismo , Nicotiana/metabolismo , Plantas Tóxicas , Secuencia de Carbohidratos , Células Cultivadas , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Morfogénesis , Oligosacáridos/metabolismo , Oxidación-Reducción , Proteínas de Plantas/metabolismo , Nicotiana/crecimiento & desarrollo
16.
Can J Gastroenterol ; 11(2): 127-34, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9113812

RESUMEN

Cisapride is a substituted benzamide with gastrointestinal prokinetic effects presumed to be due to the enhancement of the physiological release of acetylcholine at the myenteric plexus. In a multicentre study, 189 patients with nonulcer dyspepsia (NUD) received single-blind placebo treatment for two weeks. A total of 123 patients with no or minimal response to placebo and epigastric pain of at least moderate severity and frequency were randomly assigned to one of the three parallel double-blind treatments for six weeks: cisapride 10 mg tid, cisapride 20 mg tid or placebo. The severity and frequency of individual symptoms (epigastric pain, heartburn, nausea, vomiting anorexia, postprandial discomfort, regurgitation, lower abdominal pain, bloating and constipation) were assessed on a four- and five-point categorical scale, respectively, by the investigator at three on treatment visits and by patients in a daily diary. Analysis of investigator and patient assessments for differences in symptom severity x frequency composite scores among the three treatment groups showed no statistically significant differences for individual symptoms or symptom clusters. As assessed by the investigator, and compared with baseline, cisapride 20 mg tid significantly (P < 0.05) improved epigastric pain, bloating and early satiety as well as improved the total symptom cluster. Investigator evaluation of the five most severe and frequent symptoms for each patient showed statistically significant improvement in each treatment group. For patient diary assessments, statistically significant within-treatment improvement of the total symptom cluster, the five most severe symptoms cluster, bloating and early satiety was observed for both cisapride 20 mg and placebo, whereas epigastric pain significantly (P < 0.05) improved in all three treatment groups. Investigator evaluation of global response (good+excellent) rate at the end of the six week treatment period was 38% for cisapride 20 mg, 47% for cisapride 10 mg and 33% for placebo. No statistically significant difference in this parameter among treatments was noted. Cisapride was well tolerated at both doses with a side effect profile comparable with that of placebo. It is concluded that in this double-blind multicentre study with a single-blind two-week placebo run in phase, cisapride 10 mg tid and 20 mg tid were not effective compared with placebo in improving symptoms in NUD patients. This study re-emphasizes the good prognosis of patients with NUD, with 14% of patients improving in the two-week placebo run-in phase and a further 33% improving in the next six weeks while on placebo. Within-treatment analysis of investigator assessments showed improvement for cisapride 20 mg tid suggesting a trend of efficacy at this dose.


Asunto(s)
Antiulcerosos/uso terapéutico , Dispepsia/tratamiento farmacológico , Piperidinas/uso terapéutico , Administración Oral , Adulto , Análisis de Varianza , Antiulcerosos/administración & dosificación , Cisaprida , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Dispepsia/diagnóstico , Dispepsia/etiología , Femenino , Humanos , Masculino , Piperidinas/administración & dosificación , Resultado del Tratamiento
17.
Praxis (Bern 1994) ; 86(11): 432-6, 1997 Mar 11.
Artículo en Alemán | MEDLINE | ID: mdl-9190645

RESUMEN

The purpose of this evaluation was the description of potentially misleading MR appearances of osteoid osteoma. The MR images of 10 patients with osteoid osteoma were retrospectively evaluated and compared to radiographic, intraoperative and histologic findings. 4 of the 10 abnormalities were located in the proximal femur, two in the lumbar spine, and one each in the tibial plateau, in the cervical spine, in the sacrum and in the first metacarpal. 8 of the 9 nidi visible on standard radiographs and/or CT scans were demonstrated on MR images. Edema was visible within the bone marrow in 3, within soft tissue in 2 and in both locations in 4 MR examinations. The soft tissue abnormalities were circumscribed in 3 patients and could be misdiagnosed as soft tissue tumors or an abscess in these patients. One of 5 osteoid osteomas located in the proximity of a joint mimicked septic arthritis. The MR appearance of osteoid osteoma may be misleading. However, false diagnoses usually can be avoided with a careful search of a nidus. MR imaging in osteoid osteoma is important for differential diagnosis.


Asunto(s)
Neoplasias Óseas/patología , Imagen por Resonancia Magnética , Osteoma Osteoide/patología , Adolescente , Adulto , Reacciones Falso Positivas , Femenino , Neoplasias Femorales/patología , Humanos , Masculino , Estudios Retrospectivos , Neoplasias de la Columna Vertebral/patología , Tomografía Computarizada por Rayos X
20.
Development ; 108(1): 191-201, 1990 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2351064

RESUMEN

Thin cell-layer explants (TCLs) have been proposed as favorable tissues for the study of root, vegetative shoot and flower formation. We tested the effects of pH, light quality, light quantity, and IBA and kinetin concentrations on the morphogenesis of TCLs cultured individually on a liquid medium. Alterations of the amounts of exogenously supplied IBA and kinetin were sufficient to induce the formation of roots, vegetative shoots and flowers on TCLs cultured on otherwise identical media. The type and number of organs formed were sensitive to the intensity of light (55, 75, 100 and 120 muEinsteins m-2 sec-1) under which TCLs were grown. Evidence was obtained that the effects of light on TCL morphogenesis were associated with photochemical degradation of IBA in the medium. Evaluation of the organogenesis that occurred in TCLs cultured on a medium containing a range of IBA and kinetin concentrations showed that the number and type of organs formed, and overall growth, were dependent upon the initial concentrations of auxin and cytokinin. We have developed the TCL culture system into a sensitive and reproducible bioassay for the study of morphogenesis. The advantages of using the TCL morphogenesis bioassay for the identification and study of molecules (e.g. cell wall oligosaccharides) that may regulate morphogenesis are discussed.


Asunto(s)
Técnicas de Cultivo , Nicotiana , Plantas Tóxicas , Adenina/análogos & derivados , Adenina/farmacología , Concentración de Iones de Hidrógeno , Cinetina , Luz , Morfogénesis
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