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1.
Sci Total Environ ; 889: 164066, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37201844

RESUMEN

Ammonia (NH3) and nitrous oxide (N2O) emissions from livestock manure management have a significant impact on air quality and climate change. There is an increasing urgency to improve our understanding of drivers influencing these emissions. We analysed the DATAMAN ("DATAbase for MANaging greenhouse gas and ammonia emissions factors") database to identify key factors influencing (i) NH3 emission factors (EFs) for cattle and swine manure applied to land and (ii) N2O EFs for cattle and swine manure applied to land, and (iii) cattle urine, dung and sheep urine deposited during grazing. Slurry dry matter (DM) content, total ammoniacal nitrogen (TAN) concentration and method of application were significant drivers of NH3 EFs from cattle and swine slurry. Mixed effect models explained 14-59 % of the variance in NH3 EFs. Apart from the method of application, the significant influence of manure DM, manure TAN concentration or pH on NH3 EFs suggests mitigation strategies should focus on these. Identifying key factors influencing N2O EFs from manures and livestock grazing was more challenging, likely because of the complexities associated with microbial processes and soil physical properties impacting N2O production and emissions. Generally, significant factors were soil-related e.g. soil water content, pH, clay content, suggesting mitigations may need to consider the conditions of the receiving environment for manure spreading and grazing deposition. Total variability explained by terms in mixed effect model was on average 66 %, with the random effect 'experiment identification number' explaining, on average, 41 % of the total variability in the models. We suspect this term captured the effect of non-measured manure, soil and climate factors and any biases in application and measurement technique effects associated with individual experiments. This analysis has helped to improve our understanding of key factors of NH3 and N2O EFs for inclusion within models. With more studies over time, insights into the underlying processes influencing emissions will be further improved.


Asunto(s)
Amoníaco , Ganado , Óxido Nitroso , Animales , Bovinos , Amoníaco/análisis , Estiércol/análisis , Óxido Nitroso/análisis , Ovinos , Suelo/química , Porcinos
2.
Pancreatology ; 12(1): 16-22, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22487468

RESUMEN

Here we tested the prognostic impact of genomic alterations in operable localized pancreatic ductal adenocarcinoma (PDAC). Fifty-two formalin-fixed and paraffin-embedded primary PDAC were laser micro-dissected and were investigated by comparative genomic hybridization after whole genome amplification using an adapter-linker PCR. Chromosomal gains and losses were correlated to clinico-pathological parameters and clinical follow-up data. The most frequent aberration was loss on chromosome 17p (65%) while the most frequent gains were detected at 2q (41%) and 8q (41%), respectively. The concomitant occurrence of losses at 9p and 17p was found to be statistically significant. Higher rates of chromosomal losses were associated with a more advanced primary tumor stage and losses at 9p and 18q were significantly associated with presence of lymphatic metastasis (chi-square: p = 0.03, p = 0.05, respectively). Deletions on chromosome 4 were of prognostic significance for overall survival and tumor recurrence (Cox-multivariate analysis: p = 0.026 and p = 0.021, respectively). In conclusion our data suggest the common alterations at chromosome 8q, 9p, 17p and 18q as well as the prognostic relevant deletions on chromosome 4q as relevant for PDAC progression. Our comprehensive data from 52 PDAC should provide a basis for future studies with a higher resolution to discover the relevant genes located within the chromosomal aberrations identified.


Asunto(s)
Carcinoma Ductal Pancreático/genética , Deleción Cromosómica , Cromosomas Humanos Par 4 , Neoplasias Pancreáticas/genética , Adenocarcinoma/genética , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Ductal Pancreático/patología , Aberraciones Cromosómicas , Cromosomas Humanos Par 17 , Cromosomas Humanos Par 18 , Cromosomas Humanos Par 8 , Cromosomas Humanos Par 9 , Hibridación Genómica Comparativa , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/patología , Pronóstico , Análisis de Supervivencia
3.
Oper Dent ; 47(1): 87-96, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34624102

RESUMEN

OBJECTIVES: To evaluate the influence of heat application on the degree of conversion (DC) of the 3M Single Bond Universal Adhesive System, as well as its transdentinal cytotoxicity and microtensile bond strength to dentin. METHODS: Experimental groups were established according to the time and temperature of the air jet: G1: 5 seconds-25°C; G2: 10 seconds-25°C; G3: 20 seconds-25°C; G4: 5 seconds-50°C; G5: 10 seconds-50°C; G6: 20 seconds-50°C. In control group (G7), no treatment was performed. The DC was assessed using the Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) technique. For the transdentinal cytotoxicity test, dentin discs fitted in artificial pulp chambers (APC) received the application of the adhesive system and the air jets. For the microtensile bond strength, healthy molars were restored and submitted to the microtensile test after 24 hours and 6 months, respectively. RESULTS: Significant reduction in viability of Mouse Dental Papilla Cell-23 (MDPC-23), which exhibited morphological changes, was observed in all experimental groups compared to control (p<0.05). Although all tested protocols resulted in transdentinal diffusion of 2-hydroxyethyl methacrylate (HEMA), the group G6 presented the highest degree of monomeric conversion and the lowest cytotoxic effect, with higher dentin bond strength values in comparison to group G1 (p<0.05). CONCLUSIONS: Applying an air blast at 50°C for 20 seconds increases the DC and microtensile bond strength of the 3M Single Bond Universal Adhesive System to dentin, as well as reduces the transdentinal cytotoxicity of the material to pulp cells.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Animales , Resinas Compuestas/química , Cementos Dentales , Dentina , Recubrimientos Dentinarios/química , Ensayo de Materiales , Ratones , Cementos de Resina/química , Temperatura , Resistencia a la Tracción
4.
Sci Total Environ ; 732: 139235, 2020 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-32438176

RESUMEN

Globally, animal excreta (dung and urine) deposition onto grazed pastures represents more than half of anthropogenic nitrous oxide (N2O) emissions. To account for these emissions, New Zealand currently employs urine and dung emission factor (EF3) values of 1.0% and 0.25%, respectively, for all livestock. These values are primarily based on field studies conducted on fertile, flatland pastures predominantly used for dairy cattle production but do not consider emissions from hill land pastures primarily used for sheep, deer and non-dairy cattle. The objective of this study was to determine the most suitable urine and dung EF3 values for dairy cattle, non-dairy cattle, and sheep grazing pastures on different slopes based on a meta-analysis of New Zealand EF3 studies. As none of the studies included deer excreta, deer EF3 values were estimated from cattle and sheep values. The analysis revealed that a single dung EF3 value should be maintained, although the value should be reduced from 0.25% to 0.12%. Furthermore, urine EF3 should be disaggregated by livestock type (cattle > sheep) and topography (flatland and low sloping hill country > medium and steep sloping hill country), with EF3 values ranging from 0.08% (sheep urine on medium and steep slopes) to 0.98% (dairy cattle on flatland and low slopes). While the mechanism(s) causing differences in urine EF3 values for sheep and cattle are unknown, the 'slope effect' on urine EF3 is partly due to differences in soil chemical and physical characteristics, which influence soil microbial processes on the different slope classes. The revised EF3 values were used in an updated New Zealand inventory approach, resulting in 30% lower national N2O emissions for 2017 compared to using the current EF3 values. We recommend using the revised EF3 values in New Zealand's national greenhouse gas inventory to more accurately capture N2O emissions from livestock grazing.


Asunto(s)
Ganado , Animales , Bovinos , Ciervos , Nueva Zelanda , Óxido Nitroso , Ovinos , Suelo
5.
Trends Cell Biol ; 10(11): 489-93, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11050421

RESUMEN

Despite an increasing molecular-genetic understanding of the development of malignant epithelial neoplasias, the frontline therapy for patients with carcinomas is still surgery. Systemic adjuvant treatments such as chemotherapy or immunotherapy have had limited success perhaps because they are based on analysis of the primary tumour or on cell lines derived from metastasis. However, the characteristics of systemically disseminated tumour cells can be very different from that of the primary tumour or end-stage metastasis. Consequently, there is a need to study the evolution and nature of systemic cancer directly in order to identify new target structures for therapy present on the potential precursors of metastasis--the disseminated tumour cells.


Asunto(s)
Neoplasias de la Médula Ósea/secundario , Médula Ósea/patología , Metástasis de la Neoplasia , Neoplasia Residual , Neoplasias/patología , Neoplasias/fisiopatología , Animales , Médula Ósea/química , Neoplasias de la Médula Ósea/patología , Análisis Mutacional de ADN/métodos , Progresión de la Enfermedad , Células Epiteliales/patología , Células Epiteliales/fisiología , Humanos , Queratinas/análisis , Neoplasia Residual/patología , Neoplasias/diagnóstico , Neoplasias/genética , Escape del Tumor
6.
Sci Total Environ ; 610-611: 1271-1280, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28851147

RESUMEN

Grazed pastures are a major contributor to emissions of the greenhouse gas nitrous oxide (N2O), and urine deposition from grazing animals is the main source of the emissions. Incorporating alternative forages into grazing systems could be an approach for reducing N2O emissions through mechanisms such as release of biological nitrification inhibitors from roots and increased root depth. Field plot and lysimeter (intact soil column) trials were conducted in a free draining Horotiu silt loam soil to test whether two alternative forage species, plantain (Plantago lanceolate L.) and lucerne (Medicago sativa L.), could reduce N2O emissions relative to traditional pasture species, white clover (Trifolium repens L.) and perennial ryegrass (Lolium perenne L.). The amounts of N2O emitted from the soil below each forage species, which all received the same cow urine at the same rates, was measured using an established static chamber method. Total N2O emissions from the plantain, lucerne and perennial ryegrass controls (without urine application) were generally very low, but emissions from the white clover control were significantly higher. When urine was applied in autumn or winter N2O emissions from plantain were lower compared with those from perennial ryegrass or white clover, but this difference was not found when urine was applied in summer. Lucerne had lower emissions in winter but not in other seasons. Incorporation of plantain into grazed pasture could be an approach to reduce N2O emissions. However, further work is required to understand the mechanisms for the reduced emissions and the effects of environmental conditions in different seasons.

7.
Circulation ; 103(10): 1396-402, 2001 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-11245643

RESUMEN

BACKGROUND: Restenosis due to neointima formation is the major limitation of stent-supported balloon angioplasty. Despite abundant animal data, molecular mechanisms of neointima formation have been investigated on only a limited basis in patients. This study sought to establish a method for profiling gene expression in human in-stent neointima and to identify differentially expressed genes that may serve as novel therapeutic targets. METHODS AND RESULTS: We retrieved tissue specimens from patients with symptomatic in-stent restenosis using a novel helix cutter atherectomy device. cDNA samples prepared from neointima (n=10) and, as a control, from the media of normal arteries (n=14) were amplified using a novel polymerase chain reaction protocol and hybridized to cDNA arrays. Immunohistochemistry characterized the atherectomy material as neointima. cDNA arrays readily identified differentially expressed genes. Some of the differentially expressed genes complied with expected gene expression patterns of neointima, including downregulation of desmin and upregulation of thrombospondin-1, cyclooxygenase-1, and the 70-kDa heat shock protein B. Additionally, we discovered previously unknown gene expression patterns, such as downregulation of mammary-derived growth inhibitor and upregulation of FK506-binding protein 12 (FKBP12). Upregulation of FKBP12 was confirmed at the protein level in neointimal smooth muscle cells. CONCLUSIONS: Gene expression patterns of human neointima retrieved by helix-cutter atherectomy can be reliably analyzed by cDNA array technology. This technique can identify therapeutic targets in patients, as exemplified by the findings regarding FKBP12. FKBP12 is the receptor for Rapamycin (sirolimus), which in animal models reduced neointima formation. Our study thus yields a rationale for the use of Rapamycin to prevent restenosis in patients.


Asunto(s)
Constricción Patológica/genética , Proteína 1A de Unión a Tacrolimus/genética , Túnica Íntima/patología , Anciano , Aterectomía Coronaria , Constricción Patológica/etiología , Constricción Patológica/metabolismo , Constricción Patológica/patología , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa , Recurrencia , Reproducibilidad de los Resultados , Stents/efectos adversos , Túnica Media/patología , Regulación hacia Arriba
8.
Arch Intern Med ; 138(10): 1557-8, 1978 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-708179

RESUMEN

Aplastic anemia is a recognized complication of viral hepatitis, but, to our knowledge, no cases associated with type B hepatitis have been described. We report the case of a patient who developed severe aplastic anemia very early in the course of infection with hepatitis B virus.


Asunto(s)
Anemia Aplásica/complicaciones , Hepatitis B/complicaciones , Adulto , Anemia Aplásica/inmunología , Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/análisis , Humanos , Masculino
9.
Oncogene ; 34(43): 5505-12, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25659584

RESUMEN

The small GTPase Rac1 is crucial for maintaining stem cells (SCs) in mammalian epidermis, and Rac1 activation leads to SC expansion. Loss or inhibition of Rac1 correlates with decreased frequency of skin cancer formation in a chemical carcinogenesis model. Here, we have addressed whether Rac1 activation would enhance carcinogenesis and result in tumor progression. We used K14ΔNLef1 mice, a model for differentiated sebaceous adenomas (SAs), and activated Rac1 in an epidermis-specific manner (K14L61Rac1). Surprisingly, Rac1 activation did not change the incidence and frequency of sebaceous tumors. However, tumors, which occurred exclusively in K14ΔNLef1/K14L61Rac1 double-transgenic mice, were poorly differentiated resembling malignant sebaceous tumors and were termed sebaceous carcinoma-like tumors (SCLTs). Compared with SAs, SCLTs showed an aberrant pattern of cell proliferation, invasive growth and less abundant expression of sebocyte differentiation markers, including stearoyl-CoA desaturase-1 and adipophilin. Interestingly, the adnexal SC marker Lrig1 was upregulated in SCLTs, showing that active Rac1 leads to the accumulation of sebocyte precursors in the context of K14ΔNLef1-induced skin tumors. In a search for targets of Rac1, we found cancer progression-related proteins, Dhcr24/Seladin1 and Nuclear protein 1/P8, to be strongly regulated in SCLTs. At last, Rac1 and Dhcr24/Seladin1 were detected in human sebaceous tumors demonstrating a potential high impact of our findings for human skin disease. This is the first study showing that Rac1 activity can lead to malignant progression of skin tumors.


Asunto(s)
Neuropéptidos/genética , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Proteína de Unión al GTP rac1/genética , Animales , Biomarcadores de Tumor/genética , Carcinoma/genética , Carcinoma/patología , Diferenciación Celular/genética , Línea Celular Tumoral , Proliferación Celular/genética , Proteínas de Unión al ADN/genética , Progresión de la Enfermedad , Epidermis/patología , Humanos , Glicoproteínas de Membrana/genética , Proteínas de la Membrana/genética , Ratones , Ratones Transgénicos , Proteínas de Neoplasias/genética , Proteínas del Tejido Nervioso/genética , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/genética , Perilipina-2 , Estearoil-CoA Desaturasa/genética , Regulación hacia Arriba/genética
10.
Cytogenet Genome Res ; 103(1-2): 84-8, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-15004469

RESUMEN

The mouse has evolved to be the primary mammalian genetic model organism. Important applications include the modeling of human cancer and cloning experiments. In both settings, a detailed analysis of the mouse genome is essential. Multicolor karyotyping technologies have emerged to be invaluable tools for the identification of mouse chromosomes and for the deciphering of complex rearrangements. With the increasing use of these multicolor technologies resolution limits are critical. However, the traditionally used probe sets, which employ 5 different fluorochromes, have significant limitations. Here, we introduce an improved labeling strategy. Using 7 fluorochromes we increased the sensitivity for the detection of small interchromosomal rearrangements (700 kb or less) to virtually 100%. Our approach should be important to unravel small interchromosomal rearrangements in mouse models for DNA repair defects and chromosomal instability.


Asunto(s)
Aberraciones Cromosómicas , Colorantes Fluorescentes , Hibridación Fluorescente in Situ/métodos , Cariotipificación/métodos , Ratones/genética , Animales , Línea Celular , Cromosomas de los Mamíferos , Color , Femenino
11.
J Appl Physiol (1985) ; 74(5): 2432-42, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8335578

RESUMEN

We analyzed differences in host regulation of tumor necrosis factor-alpha (TNF-alpha) production and pathophysiological responses in conscious rats after infection with two strains of pathogenic Candida albicans spp. (CA-1 and CA-2) compared with Escherichia coli serotype 055:B5 (EC). The hypothesis was tested that, in contrast to EC, hypotension, organ injury, and mortality after candidemia are not obligatorily dependent on TNF-alpha or TNF-alpha-induced cyclooxygenase pathway metabolites. Dose, viability, and strain-specific dependencies were established after intravenous 10(6) or 10(9) viable CA, as well as heat-killed (HK) or Formalin-inactivated (FI) CA blastospores, compared with live EC at the 24-h LD25 [10(9) colony-forming units (CFU)] and LD100 (10(10) CFU). Shock without endotoxemia developed 4-8 h after 10(9) live CA-1 or CA-2 (LD100 at 24 h) with disseminated yeast-mycelial transformation and increased microvascular permeability in multiple organs but not after HK or FI CA-1. Peak serum TNF-alpha after an LD100 of CA-1 or CA-2 was < 3% of LD25 EC values and was < 1% of peak values during lethal bacteremia. Similar pathogen-specific differences were found in liver- and lung-associated TNF. Production of functionally inactive TNF-alpha during candidemia was excluded by enzyme-linked immunosorbent assay and sodium dodecyl sulfate-polyacrylamide gel electrophoresis with Western blotting. Passive immunization against TNF-alpha 2 h before microbial challenge was not protective against CA but prevented otherwise lethal EC sepsis. Cyclooxygenase inhibition also failed to attenuate candidemic shock. We conclude that the magnitude and kinetics of TNF-alpha production and TNF-alpha-dependent immunophysiological responses are differentially regulated after lethal fungal vs. gram-negative bacterial infection. Thus TNF-alpha is not a pivotal mediator of the acute Candida septic shock syndrome with disseminated candidiasis.


Asunto(s)
Candidiasis/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Choque Séptico/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesis , Animales , Bacteriemia/enzimología , Bacteriemia/metabolismo , Bacteriemia/fisiopatología , Presión Sanguínea/fisiología , Candidiasis/enzimología , Candidiasis/fisiopatología , Ensayo de Inmunoadsorción Enzimática , Infecciones por Escherichia coli/enzimología , Infecciones por Escherichia coli/metabolismo , Infecciones por Escherichia coli/fisiopatología , Frecuencia Cardíaca/fisiología , Humanos , Inmunización , Masculino , Tamaño de los Órganos , Prostaglandina-Endoperóxido Sintasas/fisiología , Ratas , Ratas Sprague-Dawley , Choque Séptico/enzimología , Choque Séptico/fisiopatología , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/fisiología
12.
Environ Pollut ; 186: 63-6, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24361566

RESUMEN

Between 11 May 2000 and 31 January 2013, 185 field trials were conducted across New Zealand to measure the direct nitrous oxide (N2O) emission factors (EF) from nitrogen (N) sources applied to pastoral soils. The log(EF) data were analysed statistically using a restricted maximum likelihood (REML) method. To estimate mean EF values for each N source, best linear unbiased predictors (BLUPs) were calculated. For lowland soils, mean EFs for dairy cattle urine and dung, sheep urine and dung and urea fertiliser were 1.16 ± 0.19% and 0.23 ± 0.05%, 0.55 ± 0.19% and 0.08 ± 0.02% and 0.48 ± 0.13%, respectively, each significantly different from one another (p < 0.05), except for sheep urine and urea fertiliser. For soils in terrain with slopes >12°, mean EFs were significantly lower. Thus, urine and dung EFs should be disaggregated for sheep and cattle as well as accounting for terrain.


Asunto(s)
Agricultura , Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente/métodos , Fertilizantes/estadística & datos numéricos , Óxido Nitroso/análisis , Animales , Bovinos , Nueva Zelanda , Nitrógeno/análisis , Ovinos , Suelo/química
18.
Nurse Pract ; 9(4): 56, 58, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6728340
20.
Nurse Pract ; 10(6): 42, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-4034121
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