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2.
Article in English | MEDLINE | ID: mdl-38126041

ABSTRACT

The roles and responsibilities of radiation therapists (RTTs) are many and varied. Professional expectations are influenced by the technology available, as well as the level of autonomy RTTs have in their daily practice. This professional range requires RTTs to possess a unique set of ever evolving skills, posing challenges from an educational perspective. Teaching these "advanced skills" has been the ambition the ESTRO Advanced Skills in Modern Radiotherapy course. In the 10th year of this course, the Faculty look back and reflect on how our programme has evolved and what it has achieved.

4.
BJOG ; 126(4): 459-470, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30230190

ABSTRACT

OBJECTIVE: Evidence on the impact of leisure time physical activity (LTPA) in pregnancy on birth size is inconsistent. We aimed to examine the association between LTPA during early and late pregnancy and newborn anthropometric outcomes. DESIGN: Individual level meta-analysis, which reduces heterogeneity across studies. SETTING: A consortium of eight population-based studies (seven European and one US) comprising 72 694 participants. METHODS: Generalised linear models with consistent inclusion of confounders (gestational age, sex, parity, maternal age, education, ethnicity, BMI, smoking, and alcohol intake) were used to test associations between self-reported LTPA at either early (8-18 weeks gestation) or late pregnancy (30+ weeks) and the outcomes. Results were pooled using random effects meta-analyses. MAIN OUTCOME MEASURES: Birth weight, large-for-gestational age (LGA), macrosomia, small-for-gestational age (SGA), % body fat, and ponderal index at birth. RESULTS: Late, but not early, gestation maternal moderate to vigorous physical activity (MVPA), vigorous activity, and LTPA energy expenditure were modestly inversely associated with BW, LGA, macrosomia, and ponderal index, without heterogeneity (all: I2  = 0%). For each extra hour/week of MVPA, RR for LGA and macrosomia were 0.97 (95% CI: 0.96, 0.98) and 0.96 (95% CI: 0.94, 0.98), respectively. Associations were only modestly reduced after additional adjustments for maternal BMI and gestational diabetes. No measure of LTPA was associated with risk for SGA. CONCLUSIONS: Physical activity in late, but not early, pregnancy is consistently associated with modestly lower risk of LGA and macrosomia, but not SGA. TWEETABLE ABSTRACT: In an individual participant meta-analysis, late pregnancy moderate to vigorous physical activity modestly reduced birth size outcomes.


Subject(s)
Birth Weight , Exercise , Fetal Macrosomia/epidemiology , Infant, Small for Gestational Age , Adipose Tissue , Adult , Cohort Studies , Diabetes, Gestational/epidemiology , Energy Metabolism , Female , Humans , Infant, Newborn , Linear Models , Obesity/epidemiology , Overweight/epidemiology , Pregnancy , Pregnancy Complications/epidemiology , Pregnancy Trimester, First , Pregnancy Trimester, Second , Pregnancy Trimester, Third , Protective Factors , Risk Factors , Young Adult
5.
Mol Psychiatry ; 22(7): 1044-1055, 2017 07.
Article in English | MEDLINE | ID: mdl-27137743

ABSTRACT

Post-traumatic stress disorder (PTSD) is characterized by exaggerated fear expression and impaired fear extinction. The underlying molecular and cellular mechanisms of PTSD are largely unknown. The current pharmacological and non-pharmacological treatments for PTSD are either ineffective or temporary with high relapse rates. Here we report that adiponectin-deficient mice exhibited normal contextual fear conditioning but displayed slower extinction learning. Infusions of adiponectin into the dentate gyrus (DG) of the hippocampus in fear-conditioned mice facilitated extinction of contextual fear. Whole-cell patch-clamp recordings in brain slices revealed that intrinsic excitability of DG granule neurons was enhanced by adiponectin deficiency and suppressed after treatment with the adiponectin mimetic AdipoRon, which were associated with increased input resistance and hyperpolarized resting membrane potential, respectively. Moreover, deletion of AdipoR2, but not AdipoR1 in the DG, resulted in augmented fear expression and reduced extinction, accompanied by intrinsic hyperexcitability of DG granule neurons. Adiponectin and AdipoRon failed to induce facilitation of fear extinction and elicit inhibition of intrinsic excitability of DG neurons in AdipoR2 knockout mice. These results indicated that adiponectin action via AdipoR2 was both necessary and sufficient for extinction of contextual fear and intrinsic excitability of DG granule neurons, implying that enhancing or dampening DG neuronal excitability may cause resistance to or facilitation of extinction. Therefore, our findings provide a functional link between adiponectin/AdipoR2 activation, DG neuronal excitability and contextual fear extinction, and suggest that targeting adiponectin/AdipoR2 may be used to strengthen extinction-based exposure therapies for PTSD.


Subject(s)
Adiponectin/metabolism , Dentate Gyrus/metabolism , Receptors, Adiponectin/metabolism , Action Potentials/physiology , Adiponectin/deficiency , Adiponectin/genetics , Animals , Conditioning, Classical/physiology , Disease Models, Animal , Extinction, Psychological/physiology , Fear/physiology , Female , Hippocampus , Learning/physiology , Limbic System , Male , Membrane Potentials , Metabolism, Inborn Errors/genetics , Metabolism, Inborn Errors/metabolism , Mice , Mice, Inbred C57BL , Neurons/physiology , Patch-Clamp Techniques , Prefrontal Cortex/physiology , Stress Disorders, Post-Traumatic/metabolism
6.
Oncogene ; 34(4): 424-35, 2015 Jan 22.
Article in English | MEDLINE | ID: mdl-24469032

ABSTRACT

S100A4 is implicated in metastasis and chronic inflammation, but its function remains uncertain. Here we establish an S100A4-dependent link between inflammation and metastatic tumor progression. We found that the acute-phase response proteins serum amyloid A (SAA) 1 and SAA3 are transcriptional targets of S100A4 via Toll-like receptor 4 (TLR4)/nuclear factor-κB signaling. SAA proteins stimulated the transcription of RANTES (regulated upon activation normal T-cell expressed and presumably secreted), G-CSF (granulocyte-colony-stimulating factor) and MMP2 (matrix metalloproteinase 2), MMP3, MMP9 and MMP13. We have also shown for the first time that SAA stimulate their own transcription as well as that of proinflammatory S100A8 and S100A9 proteins. Moreover, they strongly enhanced tumor cell adhesion to fibronectin, and stimulated migration and invasion of human and mouse tumor cells. Intravenously injected S100A4 protein induced expression of SAA proteins and cytokines in an organ-specific manner. In a breast cancer animal model, ectopic expression of SAA1 or SAA3 in tumor cells potently promoted widespread metastasis formation accompanied by a massive infiltration of immune cells. Furthermore, coordinate expression of S100A4 and SAA in tumor samples from colorectal carcinoma patients significantly correlated with reduced overall survival. These data show that SAA proteins are effectors for the metastasis-promoting functions of S100A4, and serve as a link between inflammation and tumor progression.


Subject(s)
Inflammation/complications , Neoplasm Metastasis , S100 Proteins/physiology , Serum Amyloid A Protein/genetics , Animals , Cell Line, Tumor , Colonic Neoplasms/mortality , ErbB Receptors/physiology , Humans , Mice , Organ Specificity , S100 Calcium-Binding Protein A4 , Serum Amyloid A Protein/physiology
7.
Obes Rev ; 15(9): 697-708, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25059108

ABSTRACT

Obesity is closely associated with cardiovascular diseases and type 2 diabetes, but some obese individuals, despite having excessive body fat, exhibit metabolic health that is comparable with that of lean individuals. The 'healthy obese' phenotype was described in the 1980s, but major advancements in its characterization were only made in the past five years. During this time, several new mechanisms that may be involved in health preservation in obesity were proposed through the use of transgenic animal models, use of sophisticated imaging techniques and in vivo measurements of insulin sensitivity. However, the main obstacle in advancing our understanding of the metabolically healthy obese phenotype and its related long-term health risks is the lack of a standardized definition. Here, we summarize the proceedings of the 13th Stock Conference of the International Association of the Study of Obesity. We describe the current research and highlight the unanswered questions and gaps in the field. Better understanding of metabolic health in obesity will assist in therapeutic decision-making and help identify therapeutic targets to improve metabolic health in obesity.


Subject(s)
Blood Glucose/metabolism , Cardiovascular Diseases/physiopathology , Insulin Resistance , Metabolic Syndrome/physiopathology , Non-alcoholic Fatty Liver Disease/physiopathology , Obesity/physiopathology , Phenotype , Body Mass Index , Cardiovascular Diseases/blood , Cardiovascular Diseases/epidemiology , Congresses as Topic , Decision Support Systems, Clinical , Gene-Environment Interaction , Humans , Metabolic Syndrome/blood , Metabolic Syndrome/epidemiology , Non-alcoholic Fatty Liver Disease/blood , Non-alcoholic Fatty Liver Disease/epidemiology , Obesity/blood , Obesity/epidemiology , Reference Standards , Risk Factors
8.
Rev Mal Respir ; 30(9): 764-73, 2013 Nov.
Article in French | MEDLINE | ID: mdl-24267767

ABSTRACT

UNLABELLED: Since December 2009, chest physicians and allergologists in Burgundy have been able to call upon a medical indoor environment counsellor (MIEC). The consultations are free for the patient and are undertaken following a medical referal after systematic cutaneous prick tests. AIMS: To describe the indications, the distribution of prescriptions and to measure the impact of the counsellor's visits on the first 100 patients at 6 months and on the physicians at 18 months. METHOD: Telephone interviews with the 67 physicians (whether prescribers or not) concerning their motivation and/or expectations, and with the first 100 patients concerning follow up of the recommendations. RESULTS: Seventy percent of the physicians replied (n=47). The satisfaction of prescribers (n=22) was 8.42/10. The indications were rhinitis and a poorly controlled asthma. The requests concerned the search for dust mite (50%) and moulds (46%). Eighty-four percent of the physicians discussed the MIEC's report with the patients. The patients' symptoms were rhinitis (79%), asthma (57%) and conjunctivitis (33%). The Acarex test(®), performed in cases of positive prick tests to house dust mites (n=72), was strongly positive for 67 patients. Sixteen mould samples out of 21 were above the standard concentrations. Sixty-nine patients had followed the recommendations of the MIEC. CONCLUSION: The impact of the MIEC visits was perceived as positive by the physicians and the patients. The medico-economic impact warrants further evaluation.


Subject(s)
Air Pollution, Indoor/prevention & control , Counseling , Patient Satisfaction , Physicians , Adolescent , Adult , Aged , Aged, 80 and over , Air Pollution, Indoor/statistics & numerical data , Animals , Asthma/diagnosis , Asthma/epidemiology , Child , Child, Preschool , Counseling/methods , Counseling/standards , Female , France/epidemiology , Humans , Infant , Male , Middle Aged , Patient Acceptance of Health Care/statistics & numerical data , Patient Satisfaction/statistics & numerical data , Physicians/statistics & numerical data , Pyroglyphidae , Rhinitis/diagnosis , Rhinitis/epidemiology , Skin Tests/statistics & numerical data , Young Adult
9.
Arq. bras. med. vet. zootec ; 65(1): 119-126, fev. 2013. ilus, tab
Article in Portuguese | LILACS | ID: lil-667545

ABSTRACT

O objetivo do estudo foi avaliar o efeito do enxerto ósseo corticoesponjoso na osteogênese em falha cortical ulnar de galinhas domésticas. Foram utilizadas 18 galinhas, com aproximadamente 70 semanas de idade e peso corpóreo médio de 2,5kg. Criou-se uma falha óssea na porção diafisária média da ulna em ambas as asas, sendo a direita utilizada como grupo-controle (grupo I) e a esquerda como grupo-tratado (grupo II). As aves foram subdivididas aleatoriamente em quatro subgrupos de acordo com o período de observação (14, 35, 60 e 90 dias). No grupo II, dois fragmentos ósseos da carena do esterno foram retirados, seccionados e implantados na falha óssea. Ao término do período de observação de cada subgrupo, as aves foram abatidas com tiopental sódico para realização dos exames histopatológico e radiográfico post-mortem, com classificação dos resultados em escala semiquantitativa (escore). O grupo II demonstrou osteogênese mais evidente aos 35 e 90 dias de pós-cirúrgico (P<0,05). Ao comparar os grupos I e II, sem levar-se em consideração o tempo de observação, foi possível observar que houve diferença estatística significativa (P<0,05). Conclui-se que o enxerto ósseo corticoesponjoso demonstra potencial osteogênico satisfatório na espécie estudada, entretanto retarda o tempo de remodelação óssea quando aplicado sobre falhas estáveis pequenas.


The aim of this survey was to evaluate the effect of cortico-cancellous bone grafting in osteogenesis in cortical ulnar failure in domestic chickens. Eighteen chickens weighing 2.5kg with approximately 70 weeks of age were used. A bone defect in the middle portion of the ulna shaft was created in both wings; the right wing in the control group (Group I) and the left in the treated group (Group II). The birds were randomly divided into four subgroups according to the observation period (14, 35, 60 and 90 days). In group II, two bone fragments of the keel of the sternum were removed, sectioned and implanted in the bone defects. At the end of the observation period for each subgroup, the birds were euthanaized with sodium thiopental to perform the histopathological and radiographic postmortem, with ranking of results in a semi-quantitative scale (score). Group II showed a more evident osteogenisis at 35 and 90 days after surgery (P<0.05). In comparing both groups, without time observation, there was statistical difference (P<0.05). In conclusion, the cortico-cancellous bone graft demonstrated satisfactory osteogenic potential in the specie studied, however, it delays the bone remodeling time when applied in stable small failures.


Subject(s)
Animals , Female , Fractures, Bone/pathology , Fractures, Bone/veterinary , Osteogenesis Imperfecta/diagnosis , Osteogenesis Imperfecta/veterinary , Bone Transplantation/veterinary , Chickens/abnormalities
10.
Cell Death Dis ; 4: e474, 2013 Jan 24.
Article in English | MEDLINE | ID: mdl-23348588

ABSTRACT

Tumor necrosis factor α (TNFα) and other members of the TNF family affect adipose tissue metabolism and contribute to the obesity-related inflammation of adipose tissue. Here, we sought to identify the effects of TRAIL (TNF-related apoptosis-inducing ligand) on fat cell biology. TRAIL-receptor 2 (TRAIL-R2) and its mouse homolog DR5 were regulated upon acute and chronic energy imbalance in murine and human adipose tissue. TRAIL inhibited insulin-stimulated glucose uptake and de novo lipogenesis in human adipocytes. Interestingly, TRAIL did not interfere with the phosphorylation of insulin-stimulated kinases such as Akt or Erk and did not activate the NF-κB pathway. Instead, TRAIL activated cleavage of caspase-8 and caspase-3. The subsequent cleavage of PPARγ led to its inactivation and resulted in reduced expression of lipogenic genes, such as Glut-4, FASN, and ACC. Taken together, we discovered a so far unknown function of the death ligand TRAIL in regulating adipocyte metabolism. Our results imply that TRAIL/TRAIL-R system might provide a new target for the prevention and treatment of obesity and its co-morbidities.


Subject(s)
Adipocytes/drug effects , Caspase 3/metabolism , Caspase 8/metabolism , PPAR gamma/metabolism , TNF-Related Apoptosis-Inducing Ligand/pharmacology , Adipocytes/metabolism , Animals , Apoptosis , Cells, Cultured , Extracellular Signal-Regulated MAP Kinases/metabolism , Fatty Acid Synthases/metabolism , Glucose/metabolism , Glucose Transporter Type 4/metabolism , Humans , Insulin/metabolism , Mice , NF-kappa B/metabolism , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Receptors, TNF-Related Apoptosis-Inducing Ligand/genetics , Receptors, TNF-Related Apoptosis-Inducing Ligand/metabolism , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Recombinant Proteins/pharmacology , TNF-Related Apoptosis-Inducing Ligand/genetics , TNF-Related Apoptosis-Inducing Ligand/metabolism
11.
Nutr Metab Cardiovasc Dis ; 23(8): 723-31, 2013 Aug.
Article in English | MEDLINE | ID: mdl-22682975

ABSTRACT

BACKGROUND AND AIMS: Crown-like structures (CLS) are characteristic histopathology features of inflamed adipose tissues in obese mice and humans. In previous work, we suggested that these cells derived from macrophages primarily involved in the reabsorption of dead adipocytes. Here, we used a well-characterized transgenic mouse model in which the death of adipocytes in adult mice is inducible and highly synchronized. In this "FAT ATTAC" model, apoptosis is induced through forced dimerization of a caspase-8 fusion protein. METHODS AND RESULTS: 0, 0.5, 1, 2, 3 and 10 days post induction of adipocyte cell death, we analyzed mesenteric and epididymal adipose depots by histology, immunohistochemistry and electron microscopy. Upon induction of caspase-8 dimerization, numerous adipocytes lost immunoreactivity for perilipin, a marker for live adipocytes. In the same areas, we found adipocytes with hypertrophic mitochondria and signs of organelle degeneration. Neutrophils and lymphocytes were the main inflammatory cells present in the tissue, and the macrophages were predominantly Mac-2 negative. Over the course of ablation, Mac-2 positive macrophages substituted for Mac-2 negative macrophages, followed by CLS formation. All perilipin negative, dead adipocytes were surrounded by CLS structures. The time course of histopathology was similar in both fat pads studied, but occurred at earlier stages and was more gradual in mesenteric fat. CONCLUSION: Our data demonstrate that CLS formation results as a direct consequence of adipocyte death, and that infiltrating macrophages actively uptake remnant lipids of dead adipocytes. Upon induction of adipocyte apoptosis, inflammatory cells infiltrate adipose tissue initially consisting of neutrophils followed by macrophages that are involved in CLS formation.


Subject(s)
Adipocytes/pathology , Adipose Tissue/pathology , Apoptosis , Lipodystrophy/pathology , Acute Disease , Adipocytes/cytology , Adiponectin/blood , Animals , Carrier Proteins/metabolism , Caspase 8/metabolism , Inflammation/pathology , Macrophages/cytology , Male , Mice , Mice, Obese , Mice, Transgenic , Microscopy, Electron , Mitochondria/pathology , Neutrophils/cytology , Perilipin-1 , Phosphoproteins/metabolism
12.
Mult Scler ; 19(5): 631-8, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23069874

ABSTRACT

BACKGROUND: Cognitive decline has been recognised as a frequent symptom in multiple sclerosis (MS). Cholinesterase inhibitors (ChEIs) are employed for the treatment of Alzheimer's disease, but there is some evidence that ChEIs might also be effective in MS patients with cognitive deficits, particularly deficits of memory function. OBJECTIVE: The aim of this study was to evaluate efficacy on memory function and safety of the ChEI rivastigmine in MS patients with cognitive deficits as measured by the change from baseline of the total recall score of the selective reminding test (SRT) after 16 weeks of treatment. METHODS: Efficacy and safety of rivastigmine were analysed in a 16-week, multicentre, double-blind, randomised, placebo-controlled study, followed by an optional one-year open-label treatment phase. Effects of rivastigmine and placebo were compared by an analysis of covariance. RESULTS: In total, 86 patients were enrolled. Patients who received rivastigmine (n = 43) showed a non-significant increase in total recall score (sum of all words immediately recalled over all six trials) over placebo (n = 38) after 16 weeks of treatment (p = 0.2576). Other outcome measures provided no evidence supporting benefits of rivastigmine. Treatment with rivastigmine was well tolerated. CONCLUSIONS: With the results of this study, the need for an effective therapy in cognitively impaired MS patients is still required. Thus, intensive and continued clinical research is required to explore therapeutic options for cognitive deficits in MS patients.


Subject(s)
Cholinesterase Inhibitors/therapeutic use , Cognition Disorders/drug therapy , Multiple Sclerosis/complications , Phenylcarbamates/therapeutic use , Adult , Cognition Disorders/etiology , Double-Blind Method , Female , Humans , Male , Mental Recall , Middle Aged , Rivastigmine , Treatment Outcome
13.
Diabetologia ; 55(9): 2319-26, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22688349

ABSTRACT

Adiponectin is an adipocyte-derived secretory protein that has been very widely studied over the past 15 years. A multitude of different functions have been attributed to this adipokine. It has been characterised in vitro at the level of tissue culture systems and in vivo through genetic manipulation of rodent models. It is also widely accepted as a biomarker in clinical studies. Originating in adipose tissue, generally positive metabolic effects have been attributed to adiponectin. In this review, we briefly discuss the key characteristics of this interesting but very complex molecule, highlight recent results in the context of its mechanism of action and summarise some of the key epidemiological data that helped establish adiponectin as a robust biomarker for insulin sensitivity, cardiovascular disease and many additional disease phenomena.


Subject(s)
Adiponectin/metabolism , Adipose Tissue/metabolism , Cardiovascular Diseases/metabolism , Inflammation/metabolism , Insulin Resistance , Receptors, Adiponectin/metabolism , Adiponectin/genetics , Animals , Biomarkers/metabolism , Cardiovascular Diseases/genetics , Gene Expression Regulation/genetics , Humans , Inflammation/genetics , Insulin Resistance/genetics , Receptors, Adiponectin/genetics
14.
Diabetologia ; 54(10): 2515-24, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21779869

ABSTRACT

AIMS/HYPOTHESIS: Plasma levels of adiponectin are inversely associated with body mass. We hypothesised that adipose tissue distribution and body composition influences adiponectin levels. METHODS: We assessed plasma adiponectin concentrations and dual-energy X-ray absorptiometry (DEXA) measurements of body composition among 2,820 participants from the Dallas Heart Study. RESULTS: Among both women and men, adiponectin levels were higher in whites than in either Hispanics or African-Americans (for women: median 9.99 µg/ml [25th,75th percentile 7.11, 13.77] vs 7.56 µg/ml [5.05, 9.98] vs 6.39 µg/ml [4.37, 9.41], respectively, p < 0.0001; for men: 6.43 µg/ml [4.66, 9.19] vs 5.55 µg/ml [3.64, 7.50] vs 5.03 µg/ml [3.39, 7.28], p < 0.0001). In univariate analysis, each individual component of body mass was inversely associated with adiponectin. After multivariate analysis, adiponectin levels were found to be positively associated with lower extremity fat, whether expressed in absolute mass (for women: ß = 0.055, p < 0.0001; for men: ß = 0.061, p < 0.0001), or as a relative proportion (for women: ß = 0.035, p < 0.0001; for men: ß = 0.034, p < 0.0001). This association was consistent across ethnicities. Conversely, adiponectin was negatively correlated with truncal fat, both in absolute (for women: ß = -0.039, p < 0.0001; for men: ß = -0.044, p < 0.0001) and relative terms (for women: ß = -0.027, p < 0.0001; for men ß = -0.033, p < 0.0001). At the extreme of body mass, higher degrees of lower extremity and truncal adiposity were associated with higher levels of adiponectin. CONCLUSIONS/INTERPRETATION: These data suggest that the location of adipose depots differentially influences circulating adiponectin concentrations-a finding observed across ethnicity and sex. Gross measures of body mass alone do not adequately account for adiponectin levels. This supports a role of adiponectin as a mediator of the positive effects of lower extremity adiposity on improvements in insulin sensitivity.


Subject(s)
Adiponectin/blood , Adipose Tissue/metabolism , Absorptiometry, Photon , Adiposity/physiology , Adult , Body Composition/physiology , Body Mass Index , Body Weight/physiology , Female , Humans , Male , Middle Aged , Multivariate Analysis , Obesity/blood , Obesity/metabolism , Young Adult
16.
Bioresour Technol ; 102(3): 2931-5, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21145230

ABSTRACT

The influence of compost as inoculum during continuous anaerobic digestion of fodder beet silage was studied over 330 days. Two simultaneously driven mesophilic fermentors (Inoc-1/Inoc-2) were inoculated with manure and sewage sludge. Only the digester Inoc-2 was inoculated additionally with compost. After 160 days fermentor Inoc-2 reached a hydraulic retention time (HRT) around 15 days whereas Inoc-1 remained at a HRT of 40d. After changing the substrate feed from one to three times a day both digesters stabilised at a shorter HRT; Inoc-2 at 10 days and Inoc-1 around 20 days. An additional inoculation of fermentor Inoc-1 by compost shortened the HRT to 10 days and revealed a minor increased gas production of about 6%. Fluorescence in situ hybridization indicated that probably an archaeal population shift was responsible for the observed stimulations. An addition of compost induced a methanogenic community change towards hydrogenotrophic methanogens.


Subject(s)
Bacteria, Anaerobic/metabolism , Beta vulgaris/microbiology , Bioreactors/microbiology , Conservation of Energy Resources/methods , Crops, Agricultural/microbiology , Ecosystem , Soil Microbiology
17.
Appl Environ Microbiol ; 76(6): 1842-50, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20097828

ABSTRACT

Beet silage and beet juice were digested continuously as representative energy crops in a thermophilic biogas fermentor for more than 7 years. Fluorescence microscopy of 15 samples covering a period of 650 days revealed that a decrease in temperature from 60 degrees C to 55 degrees C converted a morphologically uniform archaeal population (rods) into a population of methanogens exhibiting different cellular morphologies (rods and coccoid cells). A subsequent temperature increase back to 60 degrees C reestablished the uniform morphology of methanogens observed in the previous 60 degrees C period. In order to verify these observations, representative samples were investigated by amplified rRNA gene restriction analysis (ARDRA) and fluorescence in situ hybridization (FISH). Both methods confirmed the temperature-dependent population shift observed by fluorescence microscopy. Moreover, all samples investigated demonstrated that hydrogenotrophic Methanobacteriales dominated in the fermentor, as 29 of 34 identified operational taxonomic units (OTUs) were assigned to this order. This apparent discrimination of acetoclastic methanogens contradicts common models for anaerobic digestion processes, such as anaerobic digestion model 1 (ADM1), which describes the acetotrophic Euryarchaeota as predominant organisms.


Subject(s)
Archaea/growth & development , Bacteria/growth & development , Beta vulgaris/metabolism , Bioreactors/microbiology , Methane/metabolism , Silage/microbiology , Temperature , Anaerobiosis , Archaea/classification , Archaea/metabolism , Bacteria/classification , Bacteria/metabolism , DNA Fingerprinting , In Situ Hybridization, Fluorescence , Metagenomics , Molecular Sequence Data , Sequence Analysis, DNA
18.
Clin Pharmacol Ther ; 86(6): 592-5, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19915603

ABSTRACT

Biomarkers are globally used to monitor clinical responses to therapeutic and lifestyle interventions. The adipocyte-derived hormone adiponectin is recognized as a promising new biomarker owing to its many associations with components of the metabolic syndrome. The study described by Wagner and colleagues in this issue offers a first example of how a large-scale effort in the context of a cross-company collaborative study in the pharmaceutical industry can offer a powerful tool for the further validation of a new biomarker in the context of pharmacological intervention with peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonists.


Subject(s)
Blood Glucose/drug effects , Diabetes Mellitus, Type 2/drug therapy , Glycated Hemoglobin/metabolism , Hypoglycemic Agents/therapeutic use , Translational Research, Biomedical , Adiponectin/blood , Biomarkers/blood , Diabetes Mellitus, Type 2/blood , Humans , Meta-Analysis as Topic , Peroxisome Proliferator-Activated Receptors/agonists , Predictive Value of Tests , Reproducibility of Results , Time Factors , Treatment Outcome
20.
Biotechnol Bioeng ; 102(3): 736-48, 2009 Feb 15.
Article in English | MEDLINE | ID: mdl-18988261

ABSTRACT

A fuzzy logic control (FLC) system was developed at the Hamburg University of Applied Sciences (HAW Hamburg) for operation of biogas reactors running on energy crops. Three commercially available measuring parameters, namely pH, the methane (CH4) content, and the specific gas production rate (spec. GPR = m(3)/kg VS/day) were included. The objective was to avoid stabilization of pH with use of buffering supplements, like lime or manure. The developed FLC system can cover most of all applications, such as a careful start-up process and a gentle recovery strategy after a severe reactor failure, also enabling a process with a high organic loading rate (OLR) and a low hydraulic retention time (HRT), that is, a high throughput anaerobic digestion process with a stable pH and CH4 content. A precondition for a high load process was the concept of interval feeding, for example, with 8 h of interval. The FLC system was proved to be reliable during the long term fermentation studies over 3 years in one-stage, completely stirred tank reactors (CSTR) with acidic beet silage as mono-input (pH 3.3-3.4). During fermentation of the fodder beet silage (FBS), a stable HRT of 6.0 days with an OLR of up to 15 kg VS/m(3)/day and a volumetric GPR of 9 m(3)/m(3)/day could be reached. The FLC enabled an automatic recovery of the digester after two induced severe reactor failures. In another attempt to prove the feasibility of the FLC, substrate FBS was changed to sugar beet silage (SBS), which had a substantially lower buffering capacity than that of the FBS. With SBS, the FLC accomplished a stable fermentation at a pH level between 6.5 and 6.6, and a volatile fatty acid level (VFA) below 500 mg/L, but the FLC had to interact and to change the substrate dosage permanently. In a further experiment, the reactor temperature was increased from 41 to 50 degrees C. Concomitantly, the specific GPR, pH and CH4 dropped down. Finally, the FLC automatically enabled a complete recovery in 16 days.


Subject(s)
Bacteria, Anaerobic/metabolism , Electronic Data Processing/methods , Energy-Generating Resources , Fuzzy Logic , Silage , Beta vulgaris/metabolism , Biomass , Bioreactors , Buffers , Crops, Agricultural/metabolism , Fatty Acids, Volatile/metabolism , Gases/analysis , Hydrogen-Ion Concentration , Methane/analysis , Temperature
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