6 resultados para 1995_03270825 TM-47 4501707
em CentAUR: Central Archive University of Reading - UK
Resumo:
The ground surface net solar radiation is the energy that drives physical and chemical processes at the ground surface. In this paper, multi-spectral data from the Landsat-5 TM, topographic data from a gridded digital elevation model, field measurements, and the atmosphere model LOWTRAN 7 are used to estimate surface net solar radiation over the FIFE site. Firstly an improved method is presented and used for calculating total surface incoming radiation. Then, surface albedo is integrated from surface reflectance factors derived from remotely sensed data from Landsat-5 TM. Finally, surface net solar radiation is calculated by subtracting surface upwelling radiation from the total surface incoming radiation.
Resumo:
Human breast cancer cells (MCF-7, T-47-D and ZR-75-1) can adapt to circumvent any reduced growth rate during long-term oestrogen deprivation, and this provides three model systems to investigate mechanisms of endocrine resistance in breast cancer. In this paper we report consistent differences in the effects of three growth inhibitors following long-term oestrogen deprivation in all three cell models. Long-term oestrogen deprivation of MCF-7, T-47-D and ZR-75-1 cells resulted in reduced growth inhibition by PD98059 (2–10 µg/ml), implying a loss of dependence on mitogen-activated protein kinase pathways for growth. The growth inhibitor LY294002 (2–10 µM) inhibited growth of both oestrogen-maintained and oestrogen-deprived cells with similar dose–responses, implying continued similar dependence on phosphoinositide 3-kinase (PI3K) pathways with no alteration after adaptation to oestrogen independent growth. However, by contrast, long-term oestrogen deprivation resulted in an increased sensitivity to growth inhibition by rapamycin, which was not reduced by readdition of oestradiol. The enhanced inhibition of long-term oestrogen-deprived MCF-7-ED, T-47-D-ED and ZR-75-1-ED cell growth by combining rapamycin with LY294002 at concentrations where each alone had little effect, offers preclinical support to the development of therapeutic combinations of rapamycin analogues with other PI3K inhibitors in endocrine-resistant breast cancer.
Resumo:
The Phenotype MicroArray (TM) (PM) technology was used to study the metabolic characteristics of 29 Salmonella strains belonging to seven serotypes of S. enterica spp. enterica. Strains of serotypes Typhimurium (six strains among definite phage types DTs 1, 40 and 104) and Agona (two strains) were tested for 949 substrates, Enteritidis (six strains of phage type PT1), Give, Hvittingfoss, Infantis and Newport strains (two of each) were tested for 190 substrates and seven other Agona strains for 95 substrates. The strains represented 18 genotypes in pulsed-field gel electrophoresis (PFGE). Among 949 substrates, 18 were identified that could be used to differentiate between the strains of those seven serotypes or within a single serotype. Unique metabolic differences between the Finnish endemic Typhimurium DT1 and Agona strains were detected, for example, in the metabolism of d-tagatose, d-galactonic acid gamma-lactone and l-proline as a carbon source. Thus, the PM technique is a useful tool for identifying potential differential markers on a metabolic basis that could be used for epidemiological surveillance.
Resumo:
The cell walls of wheat (Triticum aestivum) starchy endosperm are dominated by arabinoxylan (AX), accounting for 65% to 70% of the polysaccharide content. Genes within two glycosyl transferase (GT) families, GT43 (IRREGULAR XYLEM9 [IRX9] and IRX14) and GT47 (IRX10), have previously been shown to be involved in the synthesis of the xylan backbone in Arabidopsis, and close homologs of these have been implicated in the synthesis of xylan in other species. Here, homologs of IRX10 TaGT47_2 and IRX9 TaGT43_2, which are highly expressed in wheat starchy endosperm cells, were suppressed by RNA interference (RNAi) constructs driven by a starchy endosperm-specific promoter. The total amount of AX was decreased by 40% to 50% and the degree of arabinosylation was increased by 25% to 30% in transgenic lines carrying either of the transgenes. The cell walls of starchy endosperm in sections of grain from TaGT43_2 and TaGT47_2 RNAi transgenics showed decreased immunolabeling for xylan and arabinoxylan epitopes and approximately 50% decreased cell wall thickness compared with controls. The proportion of AX that was water soluble was not significantly affected, but average AX polymer chain length was decreased in both TaGT43_2 and TaGT47_2 RNAi transgenics. However, the long AX chains seen in controls were absent in TaGT43_2 RNAi transgenics but still present in TaGT47_2 RNAi transgenics. The results support an emerging picture of IRX9-like and IRX10-like proteins acting as key components in the xylan synthesis machinery in both dicots and grasses. Since AX is the main component of dietary fiber in wheat foods, the TaGT43_2 and TaGT47_2 genes are of major importance to human nutrition.
Resumo:
Ethnobotanical relevance Cancer patients commonly use traditional medicines (TM) and in Thailand these are popular for both self-medication and as prescribed by TM practitioners, and are rarely monitored. A study was conducted at Wat Khampramong, a Thai Buddhist temple herbal medicine hospice, to document some of these practices as well as the hospice regime. Materials and methods Cancer patients (n=286) were surveyed shortly after admission as to which TMs they had previously taken and perceptions of effects experienced. They were also asked to describe their current symptoms. Treatment at the hospice is built upon an 11-herb anti-cancer formula, yod-ya-mareng, prescribed for all patients, and ideally, its effects would have been evaluated. However other herbal medicines and holistic practices are integral to the regime, so instead we attempted to assess the value of the patients׳ stay at the hospice by measuring any change in symptom burden, as they perceived it. Surviving patients (n=270) were therefore asked to describe their symptoms again just before leaving. Results 42% of patients (120/286; 95% CI 36.4%, 47.8%) had used herbal medicines before their arrival, with 31.7% (38/120; 95% CI 24%, 40.4%) using several at once. Mixed effects were reported for these products. After taking the herbal regime at Khampramong, 77% (208/270 95% CI; 71.7%, 81.7%) reported benefit, and a comparison of the incidence of the most common (pain, dyspepsia, abdominal or visceral pain, insomnia, fatigue) showed statistical significance (χ2 57.1, df 7, p<0.001). Conclusions A wide range of TMs is taken by cancer patients in Thailand and considered to provide more benefit than harm, and this perception extends to the temple regime. Patients reported a significant reduction in symptoms after staying at Khampramong, indicating an improvement in quality of life, the aim of hospices everywhere. Based on this evidence, it is not possible to justify the use of TM for cancer in general, but this study suggests that further research is warranted. The uncontrolled use of TMs, many of which are uncharacterised, raises concerns, and this work also highlights the fact that validated, robust methods of assessing holistic medical regimes are urgently needed.