393 research outputs found

    Use of thymidine analogues to indicate vascular perfusion in tumours

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    Temporary reduction in blood-flow within tumour blood vessels can reduce oxygen supply leading to transient perfusion-limited hypoxia. Consequent selection of cells with mutations and reduced radiosensitivity can lead to disease progression and treatment-resistance. In the present study, we investigated whether heterogeneity of labelling after thymidine analogue administration is related to perfusion variations, and if so, could it be quantified and used as a perfusion indicator. Perfusion in murine RIF1 tumours was reduced by hydralazine or increased by nicotinamide and the mice subsequently injected with IdUrd. Tumours were halved for analysis by both flow cytometry and immunohistochemistry. Tumour sections were stained for vasculature and IdUrd. Each blood vessel was scored for the density of IdUrd-labelled cells surrounding it, using a semi-quantitative scoring system. Flow cytometry showed that the IdUrd labelling index and intensity decreased by approximately 50% after hydralazine. In tumour sections of control animals, 2.9% of vessels showed no IdUrd label. In contrast, after hydralazine almost 50% of vessels had no surrounding IdUrd labelling, whereas after nicotinamide there were fewer vessels with low labelling and a higher median score. In conclusion, changes of tumour perfusion by pharmacological agents is reflected in changes in tumour-cell labelling by the thymidine analogue IdUrd, suggesting that IdUrd labelling could be used to indicate perfusion in individual vessels in human tumours. © 2000 Cancer Research Campaig

    Colonisation of Clostridium in the body is restricted to hypoxic and necrotic areas of tumours

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    The use of gene therapy is one of the most recent molecular strategies for the treatment of cancer. It is essential, however, to have an efficient transfer system by which the desired gene can be delivered to the correct environment. The experiments described in this report investigate apathogenic Clostridium as a possible vector to transfer a specific gene product into the extracellular microenvironment of the tumour which is hypoxic/necrotic in parts, using WAG/Rij rats with transplantable rhabdomyosarcomas as a model. Our data show that Clostridium, after systemic administration of at least 10(7) spores, specifically colonises the hypoxic/necrotic areas of our tumour model, the most efficient species being C. acetobutylicum (NI-4082) and C. oncolyticum. Although spores were also detected in normal tissues for up to 4 weeks, they did not germinate in these tissues. We conclude that it seems likely that these bacteria can be used as a selective transfer system into the extracellular environment of tumours which have hypoxic regions. This strategy would be more tumour-specific than various other strategies that are currently being investigated in anti-cancer gene therapy. (C) 1998 Academic Press.</p

    Plasma Ghrelin Levels Are Associated with Anorexia but Not Cachexia in Patients with NSCLC

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    Background and Aims: The ghrelin receptor is one of the new therapeutic targets in the cancer anorexia-cachexia syndrome. Previous studies revealed that plasma ghrelin levels were high in patients with anorexia nervosa and low in obese subjects. We studied to what extent ghrelin levels are related with anorexia and cachexia in patients with cancer. Materials and Methods: Fasted ghrelin levels were determined as well as anorexia and cachexia in patients with stage III/IV non-small cell lung cancer before chemotherapy. Total plasma ghrelin was measured by radioimmunoassay. Anorexia was measured with the FAACT-A/CS questionnaire (cut-off value ≤ 37). Cachexia was determined as > 5% weight loss (WL) in 6 months or > 2% WL in 6 months in combination with low BMI or low muscle mass. The Kruskal-Wallis test was performed to assess differences in plasma ghrelin levels between four groups: patients with (+) or without (-) anorexia (A) or cachexia (C). Multiple regression analyses were performed to assess differences in plasma ghrelin levels between patients C+ and C- and patients with A+ and A- (adjusted for age and sex). Results: Forty patients with stage III (33%) or stage IV (68%) were recruited, of which 50% was male. Mean age was 59.6 ± 10.3 years. Sixteen patients had no anorexia or cachexia (A-C-), seven patients had both anorexia and cachexia (A+C+), ten patients had anorexia without cachexia (A+C-) and seven patients had cachexia without anorexia (A-C+). The levels of total plasma ghrelin were significantly different between the four groups of patients with or without anorexia or cachexia (p = 0.032): the A+C- patients had significantly higher ghrelin levels [median (IQR): 1,754 (1,404-2,142) compared to the A-C+ patients 1,026 (952-1,357), p = 0.003]. A+ patients had significantly higher ghrelin levels compared A- patients (C+ and C- combined, β: 304, p = 0.020). Plasma ghrelin levels were not significantly different in C+ patients compared to C- patients (A+ and A- combined, β: -99, p = 0.450). Conclusions: Patients with anorexia had significantly higher ghrelin levels compared to patients without anorexia. We therefore hypothesize that patients with cancer anorexia might benefit from treatment with a ghrelin receptor agonist to prevent WL and deterioration in physical functioning

    Associations Between Nutrient Intake and Corresponding Nutritional Biomarker Levels in Blood in a Memory Clinic Cohort:The NUDAD Project

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    Diet is a promising intervention target to prevent or slow Alzheimer's disease (AD). Early (predementia) stages of AD offer a unique opportunity for dietary interventions. Nutritional assessment methods to estimate nutrient intake have, however, not been validated in clinical populations. Hence, we assessed the association between nutrient intake assessed by food frequency questionnaire (FFQ) and nutrient status measured by nutritional biomarkers in blood in a clinical sample of controls, mild cognitive impairment (MCI), and patients with AD

    Malnutrition in patients treated for oral or oropharyngeal cancer—prevalence and relationship with oral symptoms: an explorative study

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    This study aimed to assess prevalence of malnutrition after treatment for oral/oropharyngeal cancer and to explore how oral symptoms relate to malnutrition after treatment. In this cross-sectional study, malnutrition (weight loss a parts per thousand yenaEuro parts per thousand 10% in 6 months or a parts per thousand yen5% in 1 month), oral symptoms (EORTC QLQ-H&N35 questionnaire and additional questions to assess chewing problems), dental status, trismus and dietary intake were assessed in 116 adult patients treated for oral/oropharyngeal cancer. Prevalence of malnutrition was 16% (95%CI: 10% to 23%). Prevalence of malnutrition in the period 0-3 months after treatment was significantly higher (25%) than in the periods > 3-12 months (13%) and > 12-36 months after treatment (3%, p = 0.008). Logistic multivariate regression analysis revealed that swallowing problems (p = 0.021) and insufficient protein intake were significantly related to malnutrition (p = 0.016). In conclusion, malnutrition is a considerable problem in patients treated for oral/oropharyngeal cancer, shortly after treatment. Of all oral symptoms, only swallowing problems were significantly related to malnutrition in the period after treatment for oral/oropharyngeal cancer

    Global Leadership Initiative on Malnutrition (GLIM):Guidance on Validation of the Operational Criteria for the Diagnosis of Protein-Energy Malnutrition in Adults

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    Background The Global Leadership Initiative on Malnutrition (GLIM) created a consensus-based framework consisting of phenotypic and etiologic criteria to record the occurrence of malnutrition in adults. This is a minimum set of practicable indicators for use in characterizing a patient/client as malnourished, considering the global variations in screening and nutrition assessment, and to be used across different healthcare settings. As with other consensus-based frameworks for diagnosing disease states, these operational criteria require validation and reliability testing, as they are currently based solely on expert opinion. Methods Several forms of validation and reliability are reviewed in the context of GLIM, providing guidance on how to conduct retrospective and prospective studies for criterion and construct validity. Results There are some aspects of GLIM that require refinement; research using large databases can be employed to reach this goal. Machine learning is also introduced as a potential method to support identification of the best cut points and combinations of indicators for use with the different forms of malnutrition, which the GLIM criteria were created to denote. It is noted as well that validation and reliability testing need to occur in a variety of sectors and populations and with diverse persons using GLIM criteria. Conclusion The guidance presented supports the conduct and publication of quality validation and reliability studies for GLIM

    Slow Photons for Photocatalysis and Photovoltaics.

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    Solar light is widely recognized as one of the most valuable renewable energy sources for the future. However, the development of solar-energy technologies is severely hindered by poor energy-conversion efficiencies due to low optical-absorption coefficients and low quantum-conversion yield of current-generation materials. Huge efforts have been devoted to investigating new strategies to improve the utilization of solar energy. Different chemical and physical strategies have been used to extend the spectral range or increase the conversion efficiency of materials, leading to very promising results. However, these methods have now begun to reach their limits. What is therefore the next big concept that could efficiently be used to enhance light harvesting? Despite its discovery many years ago, with the potential for becoming a powerful tool for enhanced light harvesting, the slow-photon effect, a manifestation of light-propagation control due to photonic structures, has largely been overlooked. This review presents theoretical as well as experimental progress on this effect, revealing that the photoreactivity of materials can be dramatically enhanced by exploiting slow photons. It is predicted that successful implementation of this strategy may open a very promising avenue for a broad spectrum of light-energy-conversion technologies.This work was realized in the frame of a program for Changjiang Scholars and Innovative Research Team (IRT_15R52) of the Chinese Ministry of Education. B.V.d.S. acknowledges FRIA funding from the Fonds National de la Recherche Scientifique (FNRS). T.H. acknowledges support from a Royal Academy of Engineering Fellowship, B.L.S. acknowledges the Chinese Central Government for an “Expert of the State” position in the Program of the “Thousand Talents”, the Chinese Ministry of Education for a Changjiang Scholar position at the Wuhan University of Technology, a Clare Hall Life Membership, University of Cambridge. This work was also financially supported by National Natural Science Foundation of China (Grant No.51502225), the Fundamental Research Funds for the Central Universities (2013-YB-024, 2014-IV-057), Hubei Provincial Natural Science Foundation (2015CFB516), and Self-determined and Innovative Research Funds of the SKLWUT (2015-ZD-7) and International Science & Technology Cooperation Program of China (ISTC-2015DFE52870). G.A.O. is a Government of Canada Research Chair in Materials Chemistry and Nanochemistry. Financial support for this work was provided by the Ontario Ministry of Research Innovation (MRI); Ministry of Economic Development, Employment and Infrastructure (MEDI); Ministry of the Environment and Climate Change; Connaught Global Challenge Fund; Natural Sciences and Engineering Research Council of Canada (NSERC)

    Assessment of Nutritional Status, Digestion and Absorption, and Quality of Life in Patients with Locally Advanced Pancreatic Cancer

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    Background and Aim. To provide a comprehensive quantitative assessment of nutritional status, digestion and absorption, and quality of life (QoL) in patients with locally advanced pancreatic cancer (LAPC). Methods. Sixteen patients with LAPC were prospectively assessed for weight loss (WL), body mass index (BMI), fat-free mass index (FFMI), handgrip strength (HGS), dietary macronutrient intake, serum vitamin levels, resting and total energy expenditure (REE and TEE, indirect calorimetry), intestinal absorption capacity and fecal losses (bomb calorimetry), exocrine pancreatic function (fecal elastase-1 (FE1)), and gastrointestinal quality of life (GIQLI). Results. Two patients had a low BMI, 10 patients had WL > 10%/6 months, 8 patients had a FFMI < P10, and 8 patients had a HGS < P10. Measured REE was 33% higher (P=0.002) than predicted REE. TEE was significantly higher than daily energy intake (P=0.047). Malabsorption (<85%) of energy, fat, protein, and carbohydrates was observed in, respectively, 9, 8, 12, and 10 patients. FE1 levels were low (<200 μg/g) in 13 patients. Total QoL scored 71% (ample satisfactory). Conclusion. Patients with LAPC have a severely impaired nutritional status, most likely as a result of an increased REE and malabsorption due to exocrine pancreatic insufficiency. The trial is registered with PANFIRE clinicaltrials.gov NCT01939665

    ESPEN guidelines on definitions and terminology of clinical nutrition

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    BACKGROUND: A lack of agreement on definitions and terminology used for nutrition-related concepts and procedures limits the development of clinical nutrition practice and research. OBJECTIVE: This initiative aimed to reach a consensus for terminology for core nutritional concepts and procedures. METHODS: The European Society of Clinical Nutrition and Metabolism (ESPEN) appointed a consensus group of clinical scientists to perform a modified Delphi process that encompassed e-mail communication, face-to-face meetings, in-group ballots and an electronic ESPEN membership Delphi round. RESULTS: Five key areas related to clinical nutrition were identified: concepts; procedures; organisation; delivery; and products. One core concept of clinical nutrition is malnutrition/undernutrition, which includes disease-related malnutrition (DRM) with (eq. cachexia) and without inflammation, and malnutrition/undernutrition without disease, e.g. hunger-related malnutrition. Over-nutrition (overweight and obesity) is another core concept. Sarcopenia and frailty were agreed to be separate conditions often associated with malnutrition. Examples of nutritional procedures identified include screening for subjects at nutritional risk followed by a complete nutritional assessment. Hospital and care facility catering are the basic organizational forms for providing nutrition. Oral nutritional supplementation is the preferred way of nutrition therapy but if inadequate then other forms of medical nutrition therapy, i.e. enteral tube feeding and parenteral (intravenous) nutrition, becomes the major way of nutrient delivery. CONCLUSION: An agreement of basic nutritional terminology to be used in clinical practice, research, and the ESPEN guideline developments has been established. This terminology consensus may help to support future global consensus efforts and updates of classification systems such as the International Classification of Disease (ICD). The continuous growth of knowledge in all areas addressed in this statement will provide the foundation for future revisions
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