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1.
Clin Exp Allergy ; 48(4): 424-432, 2018 04.
Article in English | MEDLINE | ID: mdl-29369458

ABSTRACT

BACKGROUND: Celery (Apium graveolens L.) is a vegetable consumed world-wide. Celery stalks and celeriac roots are often ingredients in convenient food products like spice blends and soups. OBJECTIVE: In this study, we examined the allergenicity of distinct celeriac cultivars. METHODS: Sixteen celery-allergic patients were identified using a double-blind, placebo-controlled food challenge. Ten different celeriac cultivars were used for skin prick testing in the patients. Two cultivars were further applied for oral food challenges; their protein composition was analysed by immunoblotting, and contents of major allergen Api g 1 were quantified. RESULTS: From the 10 investigated celeriac cultivars, two cultivars elicited significantly different skin reactivity ("Anita": 5.0 [2.0-12.0] mm vs "Prinz": 7.0 [3.0-9.5] mm; P = .047). Moreover, "Anita" induced fewer symptoms after a controlled oral-celeriac challenge in 14 patient (P < .001). The protein profiles on 2DE protein gels showed distinct protein patterns and higher protein amounts of Api g 1 in "Prinz" than in "Anita." CONCLUSIONS AND CLINICAL RELEVANCE: Taken together, the data from this study suggest that cultivar Anita is better tolerated in celery-allergic patients than "Prinz." Differences in the protein expression profile between the cultivars, particularly the different content of Api g 1, could cause the different allergenicity.


Subject(s)
Antigens, Plant/immunology , Apium/immunology , Food Hypersensitivity/immunology , Plant Proteins/immunology , Adult , Double-Blind Method , Female , Humans , Male , Middle Aged , Young Adult
2.
Gynecol Obstet Fertil ; 44(9): 487-91, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27568406

ABSTRACT

OBJECTIVE: Sentinel lymph node biopsy (SLNB) is a standard for patients with early breast cancer. Using a gamma-detecting probe connected to an infrared camera, the Declipse freehand SPECT (FhSPECT) system (Surgiceye(®)) is able to detect and locate any radioactive source in 3D. The objective of this study was to evaluate the potential interest of FhSPECT imaging for real-time guidance SLNB in breast cancer. METHODS: A prospective single-center clinical study assessed sensitivity and usability of FhSPECT for SLN detection and surgical guidance in breast cancer patients. SLN detection rate with FhSPECT was compared with lymphoscintigraphy (LS) and colorimetric method. Durations of FhSPECT acquisitions and of the SLNB procedure were measured in order to evaluate the practicability of the device. RESULTS: Between May and September 2014, 20 patients with early stage invasive breast cancer (cT0-2N0) underwent SLNB using FhSPECT and blue dye detection. Preoperative LS revealed 41 radioactive axillary SLNs (median=2 SLN per patient; range 0-4) in 20 patients. Preoperative FhSPECT detected 40 axillary SLNs (median=2; range: 1-4) in 20 patients. The corresponding sensitivity of FhSPECT was 97.5%. For 4 patients (20%), FhSPECT detected more axillary SLNs than LS. The colorimetric method identified only 24 axillary SLNs (2 patients had no blue dye injection on account of a history of allergy), leading to a sensitivity of 67% (24 blue SLNs/36 resected SLNs after blue dye injection). Median duration of FhSPECT acquisitions was 5minutes (range: 1-26min). Median duration of SLNB procedure was 11.5minutes (range: 3-55min). Duration of acquisitions analysis based on the number of use of the device showed decreasing values suggesting the existence of a short learning curve. CONCLUSION: This study demonstrated that FhSPECT is feasible and facilitates SLN identification.


Subject(s)
Breast Neoplasms/pathology , Sentinel Lymph Node Biopsy/methods , Tomography, Emission-Computed, Single-Photon , Aged , Axilla , Breast Neoplasms/surgery , Female , Humans , Lymphatic Metastasis/pathology , Middle Aged , Prospective Studies , Sensitivity and Specificity , Sentinel Lymph Node/pathology
3.
Cell Death Differ ; 23(1): 18-28, 2016 Jan.
Article in English | MEDLINE | ID: mdl-25909888

ABSTRACT

Well-balanced mitochondrial fission and fusion processes are essential for nervous system development. Loss of function of the main mitochondrial fission mediator, dynamin-related protein 1 (Drp1), is lethal early during embryonic development or around birth, but the role of mitochondrial fission in adult neurons remains unclear. Here we show that inducible Drp1 ablation in neurons of the adult mouse forebrain results in progressive, neuronal subtype-specific alterations of mitochondrial morphology in the hippocampus that are marginally responsive to antioxidant treatment. Furthermore, DRP1 loss affects synaptic transmission and memory function. Although these changes culminate in hippocampal atrophy, they are not sufficient to cause neuronal cell death within 10 weeks of genetic Drp1 ablation. Collectively, our in vivo observations clarify the role of mitochondrial fission in neurons, demonstrating that Drp1 ablation in adult forebrain neurons compromises critical neuronal functions without causing overt neurodegeneration.


Subject(s)
Atrophy/genetics , Dynamins/genetics , Nervous System/growth & development , Neurons/metabolism , Animals , Antioxidants/administration & dosage , Atrophy/metabolism , Atrophy/pathology , Dynamins/biosynthesis , Hippocampus/growth & development , Hippocampus/metabolism , Hippocampus/pathology , Memory Disorders/genetics , Memory Disorders/pathology , Mice , Mitochondria/metabolism , Mitochondria/pathology , Mitochondrial Dynamics/genetics , Nerve Degeneration/genetics , Nerve Degeneration/metabolism , Nerve Degeneration/pathology , Nervous System/pathology , Neurons/pathology , Prosencephalon/growth & development , Prosencephalon/metabolism , Prosencephalon/pathology
4.
Diabetes Obes Metab ; 17 Suppl 1: 23-32, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26332965

ABSTRACT

The mammalian circadian timing system consists of a central pacemaker in the brain's suprachiasmatic nucleus (SCN) and subsidiary oscillators in nearly all body cells. The SCN clock, which is adjusted to geophysical time by the photoperiod, synchronizes peripheral clocks through a wide variety of systemic cues. The latter include signals depending on feeding cycles, glucocorticoid hormones, rhythmic blood-borne signals eliciting daily changes in actin dynamics and serum response factor (SRF) activity, and sensors of body temperature rhythms, such as heat shock transcription factors and the cold-inducible RNA-binding protein CIRP. To study these systemic signalling pathways, we designed and engineered a novel, highly photosensitive apparatus, dubbed RT-Biolumicorder. This device enables us to record circadian luciferase reporter gene expression in the liver and other organs of freely moving mice over months in real time. Owing to the multitude of systemic signalling pathway involved in the phase resetting of peripheral clocks the disruption of any particular one has only minor effects on the steady state phase of circadian gene expression in organs such as the liver. Nonetheless, the implication of specific pathways in the synchronization of clock gene expression can readily be assessed by monitoring the phase-shifting kinetics using the RT-Biolumicorder.


Subject(s)
CLOCK Proteins/metabolism , Circadian Clocks/physiology , Circadian Rhythm/genetics , Gene Expression , Signal Transduction/genetics , Suprachiasmatic Nucleus/physiology , Animals , Circadian Rhythm/physiology , Equipment Design , Genes, Reporter/physiology , Glucocorticoids/physiology , Liver/metabolism , Luciferases/genetics , Luciferases/metabolism , Mice
5.
Gynecol Obstet Fertil ; 43(2): 172-5, 2015 Feb.
Article in French | MEDLINE | ID: mdl-25155906

ABSTRACT

The sentinel lymph node (SLN) is a standard for the surgical treatment of axillary localized breast cancer N0. It is based on a double isotopic and color detection. With a gamma detecting probe connected to an infrared camera, Déclipse SPECT system (Surgiceye(®)) is able to detect and locate any radioactive source in 3D. Mobile character for use in the operating room is particularly interesting for the intraoperative detection of SLN. We illustrate its usefulness in a clinical case where the preoperative identification of SLN by lymphoscintigraphy was not informative.


Subject(s)
Breast Neoplasms/pathology , Lymph Nodes/diagnostic imaging , Sentinel Lymph Node Biopsy/methods , Tomography, Emission-Computed, Single-Photon , Female , Humans
6.
Clin Exp Allergy ; 43(12): 1419-27, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24118131

ABSTRACT

BACKGROUND: Tomato became one of the world-wide most consumed vegetables, unfortunately accompanied by an increasing risk of tomato allergy affecting certain people. As tomato allergic subjects show highly variable reactions in clinical allergy tests, it is difficult to identify cultivars or differentially treated tomato plants where a significant reduction in the allergenic potential over all subjects of a cohort can be detected. OBJECTIVE: This study was carried out to test the hypothesis that individual variability is based on differential reactions of single subjects to particular allergens in tomato fruits of plants with certain genetic background or cultivated under distinct conditions. METHODS: Proteins were extracted from tomato fruits of the previously investigated genotypes 76R, its mycorrhizal mutant RMC, and the cultivar Counter, fertilized with different forms of nitrogen in deficit or excess. 2-D immunoblots were carried out with sera of nine tomato allergic subjects, beforehand analysed in skin prick tests. RESULTS: In total, ten putative tomato allergens were identified in these immunoblots. No correlation was detected between individual skin prick test results and the quantity of positive reactions to putative allergens. IgEs of each subject showed reactions to nearly every identified putative allergen, but reactions were dependent on genotype and growth conditions. Among the ten putative tomato allergens, five new candidates were identified as follows: an endo-ß-mannanase, a pectinacetylesterase, a pectinesterase inhibitor, an aspartyl protease family protein and a protein of unknown function. CONCLUSION AND CLINICAL RELEVANCE: The hypothesis that high interindividual differences in allergic reactions are based on the interactions between the IgEs of allergic subjects with particular allergens has to be rejected. However, five proteins with putative clinical relevance as tomato allergens could be newly identified.


Subject(s)
Allergens/immunology , Antigens, Plant/immunology , Food Hypersensitivity/immunology , Immunoglobulin E/immunology , Solanum lycopersicum/adverse effects , Adolescent , Adult , Allergens/metabolism , Antigens, Plant/metabolism , Female , Food Hypersensitivity/diagnosis , Food Hypersensitivity/metabolism , Humans , Immunoglobulin E/metabolism , Male , Plant Proteins/immunology , Plant Proteins/metabolism , Proteomics/methods , Skin Tests , Young Adult
7.
Phys Med Biol ; 58(8): 2657-74, 2013 Apr 21.
Article in English | MEDLINE | ID: mdl-23552770

ABSTRACT

Respiratory motion can blur the tomographic reconstruction of positron emission tomography or single-photon emission computed tomography (SPECT) images, which subsequently impair quantitative measurements, e.g. in the upper abdomen area. Respiratory signal phase-based gated reconstruction addresses this problem, but deteriorates the signal-to-noise ratio (SNR) and other intensity-based quality measures. This paper proposes a 3D reconstruction method dedicated to micro-SPECT imaging of mice. From a 4D acquisition, the phase images exhibiting motion are identified and the associated list-mode data are discarded, which enables the reconstruction of a 3D image without respiratory artefacts. The proposed method allows a motion-free reconstruction exhibiting both satisfactory count statistics and accuracy of measures. With respect to standard 3D reconstruction (non-gated 3D reconstruction) without breathing motion correction, an increase of 14.6% of the mean standardized uptake value has been observed, while, with respect to a gated 4D reconstruction, up to 60% less noise and an increase of up to 124% of the SNR have been demonstrated.


Subject(s)
Imaging, Three-Dimensional/methods , Tomography, Emission-Computed, Single-Photon/methods , Animals , Female , Mice , Peritoneal Neoplasms/diagnostic imaging , Peritoneal Neoplasms/physiopathology , Rats , Respiration , Retrospective Studies
8.
Oncogene ; 32(38): 4579-85, 2013 Sep 19.
Article in English | MEDLINE | ID: mdl-23045279

ABSTRACT

Apc-driven tumor formation in patients and Apc-mutant mouse models is generally attributed to increased levels of ß-catenin signaling. We and others have proposed that a specific level of ß-catenin signaling is required to successfully initiate tumor formation, and that each tissue prefers different dosages of signaling. This is illustrated by APC genotype-tumor phenotype correlations in cancer patients, and by the different tumor phenotypes displayed by different Apc-mutant mouse models. Apc1638N mice, associated with intermediate ß-catenin signaling, characteristically develop intestinal tumors (<10) and extra-intestinal tumors, including cysts and desmoids. Apc1572T mice associated with lower levels of ß-catenin signaling are free of intestinal tumors, but instead develop mammary tumors. Although the concept of ß-catenin signaling dosage and its impact on tumor growth among tissues is gaining acceptance, it has not been formally proven. Additionally, alternative explanations for Apc-driven tumor formation have been proposed. To obtain direct evidence for the dominant role of ß-catenin dosage in tumor formation and tissue-specific tumor predisposition, we crossed Apc1638N mice with heterozygous ß-catenin knockout mice, thereby reducing ß-catenin levels. Whereas all the Apc1638N;Ctnnb1(+/+) mice developed gastrointestinal tumors, none were present in the Apc1638N;Ctnnb1(-/+) mice. Incidence of other Apc1638N-associated lesions, including desmoids and cysts, was strongly reduced as well. Interestingly, Apc1638N;Ctnnb1(-/+) females showed an increased incidence of mammary tumors, which are normally rarely observed in Apc1638N mice, and the histological composition of the tumors resembled that of Apc1572T-related tumors. Hereby, we provide in vivo genetic evidence confirming the dominant role of ß-catenin dosage in tumor formation and in dictating tumor predisposition among tissues in Apc-driven cancer.


Subject(s)
Genes, APC , Neoplasms/genetics , Neoplasms/metabolism , Signal Transduction , beta Catenin/metabolism , Animals , Disease Models, Animal , Female , Genetic Predisposition to Disease , Genotype , Humans , Male , Mice , Mice, Knockout , Mice, Transgenic , Neoplasms/pathology , beta Catenin/genetics
9.
Appl Microbiol Biotechnol ; 96(6): 1455-64, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23108570

ABSTRACT

The successful conversion of plant production systems from conventional resource-exhausting to sustainable strategies depends on knowledge-based management of environmental factors. Root-inhabiting fungi came more and more into focus because their hyphae connect in ideal manner resources and challenges of the surrounding with the plant. A paradigm for such root endophytes is presented by the basidiomycete Piriformospora indica. This fungus possesses a broad host spectrum and positively affects different aspects of plant performance. This so far unique combination of attributes makes P. indica and its close relatives among the Sebacinales very interesting tools for cultivation of various crops. This review will outline the different aspects required to apply this root endophyte in agri- and horticulture concerning plant growth, plant nutrition and plant defence or tolerance thereby explaining what is known about the biological basis for the observed effects. Open questions and challenges for successful inoculum production and application will be discussed.


Subject(s)
Basidiomycota/physiology , Endophytes/physiology , Plant Roots/microbiology , Host Specificity , Plant Roots/growth & development , Plant Roots/physiology
10.
Curr Pharm Des ; 18(22): 3313-20, 2012.
Article in English | MEDLINE | ID: mdl-22397732

ABSTRACT

Radiovirotherapy is defined as the use of viruses to deliver radioisotopic treatment into infected cells. Oncolytic viruses are able to selectively target and kill cancer cells. The combination of oncolytic viruses and radiation therapies can have synergistic antitumour properties. Viruses may act as radiosensitizers, and radiations can increase viral oncolytic properties. The combination of oncolytic viruses with a virally-directed radioisotope therapy is an innovative method to combine viruses and radiation therapy, selectively within the tumour cells. The sodium/iodide symporter (NIS) is the main transgene that has been studied for this approach. NIS can mediate the uptake of isotopes of iodine and technetium 99m for in vivo gene expression imaging and therapy. This review highlights the principles of radiovirotherapy, and its recent progress. Better understanding of the regulation of NIS opens up pathways by which to potentiate the functional expression of NIS. In terms of the therapeutic isotope, Iodine-131 has been most frequently studied but other isotopes (astatine- 211, rhenium-188) are of growing interest. Oncolytic viruses are able to infect selectively and replicate in cancer cells and promising early phase clinical trials have been recently published. Their development allows a better selectivity of viral infection and adds a virus-specific cytotoxicity to the therapeutic approach. Active research into strategies such as immunosuppressive treatment and cell-based carrier systems is seeking to circumvent the host antiviral immune response and, thus, increase the potential for systemic delivery. Finally, other anticancer therapies such as chemotherapy and external beam radiotherapy may have a synergistic effect with radiovirotherapy and such combinatorial approaches offering the prospect of accelerated translation into clinical studies.


Subject(s)
Neoplasms/therapy , Oncolytic Virotherapy/methods , Radioisotopes/administration & dosage , Animals , Antineoplastic Agents/therapeutic use , Combined Modality Therapy , Gene Expression Regulation, Neoplastic , Humans , Neoplasms/genetics , Neoplasms/pathology , Oncolytic Viruses , Symporters/genetics , Symporters/metabolism
11.
Clin Exp Allergy ; 41(11): 1643-52, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21955222

ABSTRACT

BACKGROUND: Tomatoes (Solanum lycopersicum) are consumed worldwide and their amount of consumption is associated with the prevalence of tomato allergy. Therefore, identification of tomato cultivars with reduced allergenicity would potentially increase the quality of life of affected subjects. OBJECTIVE: In this study, we examined the allergenic and biological activity of two different tomato cultivars in tomato allergic subjects. METHODS: Twenty-five subjects with tomato allergy were identified using double-blind, placebo-controlled food challenges (DBPCFC). We applied skin prick test (SPT) and further DBPCFC to investigate the clinical differences between two tomato cultivars ('Reisetomate' and 'Matina'). To examine the molecular basis of allergenic activity, immunoblotting and basophil activation test (BAT) were performed. RESULTS: The cultivar 'Reisetomate' induced significantly less positive skin reactions (P = 0.045) and elicited fewer symptoms after oral challenge compared with 'Matina' (P = 0.047). Molecular assessment revealed that IgE-binding profiles were variable on an interindividual basis, but no major differences between 'Reisetomate' and 'Matina' were detectable. In contrast, BAT underpinned the clinical differences evoked by the different tomato cultivars and showed a left-shift of the dose-response curve obtained for 'Matina' extract (P = 0.046). CONCLUSIONS AND CLINICAL RELEVANCE: Tomato cultivars promote a distinct clinical reactivity in tomato allergic subjects, demonstrated using SPT, DBPCFC and BAT. The molecular background for these differences could not be clarified, as the IgE-binding profiles did not reveal significant alterations. This might be due to instabilities of physicochemical sensitive proteins and/or different isoform expression of allergens.


Subject(s)
Antigens, Plant/immunology , Food Hypersensitivity/immunology , Solanum lycopersicum/adverse effects , Adolescent , Adult , Aged , Antigens, Plant/metabolism , Basophil Degranulation Test , Basophils/immunology , Female , Food Hypersensitivity/diagnosis , Humans , Immunoglobulin E/immunology , Immunoglobulin E/metabolism , Male , Middle Aged , Protein Binding/immunology , Skin Tests , Young Adult
12.
Dis Esophagus ; 24(5): 371-3, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21166735

ABSTRACT

Recently, a mouse model for Barrett's esophagus based on a zinc-deficient diet supplemented with deoxycholic bile acids has been published. The aim of this study was to attempt to reproduce these data and extend them by employing genetically modified mice and intraperitoneal iron supplementation. The study design encompassed six experimental groups (wild type, Apc-mutant and Smad4-mutant mice, with or without iron injections), with all animals fed with the zinc-deficient diet supplemented with deoxycholic bile acids. All treatments were started at 3-5 weeks of age (the majority [78%] at 5 weeks). Animals were scheduled for euthanasia at two distinct time points, namely at 3 and 6 months of age. All mice showed signs of considerable distress already 4 weeks after the start of the modified diets, and had to be euthanized before the first evaluation time point (mean age 9.3 weeks, range 5-15 weeks). No differences were observed between wild type and genetically modified mice, or between animals with or without iron supplementation. On histological examination, we could not detect any lesions (Barrett's esophagus-like or tumors) other than esophagitis. In the currently presented experimental settings, we were not able to reproduce the mouse model according to which Barrett's-like lesions could be detected in animals fed with the zinc-deficient diet supplemented with deoxycholic bile acids.


Subject(s)
Barrett Esophagus/chemically induced , Cholagogues and Choleretics/administration & dosage , Deoxycholic Acid/administration & dosage , Dietary Supplements/adverse effects , Disease Models, Animal , Trace Elements/deficiency , Zinc/deficiency , Animals , Barrett Esophagus/pathology , Diet/adverse effects , Esophagitis/chemically induced , Esophagitis/pathology , Iron/administration & dosage , Mice , Mice, Mutant Strains , Reproducibility of Results , Smad4 Protein/genetics , Trace Elements/administration & dosage
13.
Prev Vet Med ; 93(4): 305-15, 2010 Mar 01.
Article in English | MEDLINE | ID: mdl-20005587

ABSTRACT

Paratuberculosis is a chronic intestinal infection in ruminants, caused by Mycobacterium avium subspecies paratuberculosis (Map). To study the role of host genetics in disease susceptibility, the Toll-like receptor 2 (TLR2) gene, selected based on its potential role in immunity to mycobacterial infections, was analyzed for single nucleotide polymorphisms (SNP) and their potential association with disease. For SNP discovery and to study SNP association with disease, a case-control study including 24 cows from farms with paratuberculosis was conducted. Sequence analysis of the TLR2 genes from 12 paratuberculosis-infected animals and 12 age-matched healthy herd mates revealed 21 different SNP. The TLR2-1903 T/C SNP was significantly associated with resistance to Map. This and four additional TLR2 SNP were studied in a subsequent observational field study with 553 cows from farms with paratuberculosis. The allelic distribution of the TLR2-1903 T/C SNP was confirmed to be significantly different between the infected and non-infected animals. For the TLR2-1903 T/C SNP the odds ratio was calculated, and similar to the dominance model in the association study, the CT and CC genotypes were compared to the TT genotype. Cows with the TLR2-1903 T/C mutation (i.e., the CT and CC genotypes) were at 1.7 (95% CI: 1.2, 2.8) times the odds of being Map-infected compared to cows with the TT genotype. In in vitro functional assays, monocyte-derived macrophages from animals with a TLR2-1903 TT genotype produced more IL12p40 and IL1beta when stimulated with Map compared to cells derived from TLR2-1903 CT and CC genotypes. Also, T cell proliferative responses to mycobacterial antigens were higher in animals with a TLR2-1903 TT genotype. In conclusion, we have found a significant association between SNP TLR2-1903 T/C in the bovine TLR2 gene and bovine paratuberculosis infection. This SNP and other genetic markers could be useful in marker-assisted breeding strategies as an additional tool in paratuberculosis control strategies. In addition, the functional studies suggest that genetic polymorphisms in bovine TLR2 which result in higher macrophage activity may contribute to enhanced T cell activation and a lower susceptibility to paratuberculosis in cattle.


Subject(s)
Cattle Diseases/immunology , Mycobacterium avium subsp. paratuberculosis/immunology , Paratuberculosis/immunology , Toll-Like Receptor 2/genetics , Amino Acid Sequence , Animals , Case-Control Studies , Cattle , Cattle Diseases/genetics , Female , Genetic Testing , Molecular Sequence Data , Paratuberculosis/genetics , Polymorphism, Single Nucleotide
14.
Eur J Neurosci ; 29(9): 1820-9, 2009 May.
Article in English | MEDLINE | ID: mdl-19473235

ABSTRACT

Circadian and sleep-homeostatic processes both contribute to sleep timing and sleep structure. Elimination of circadian rhythms through lesions of the suprachiasmatic nuclei (SCN), the master circadian pacemaker, leads to fragmentation of wakefulness and sleep but does not eliminate the homeostatic response to sleep loss as indexed by the increase in EEG delta power. In humans, EEG delta power declines during sleep episodes nearly independently of circadian phase. Such observations have contributed to the prevailing notion that circadian and homeostatic processes are separate but recent data imply that this segregation may not extend to the molecular level. Here we summarize the criteria and evidence for a role for clock genes in sleep homeostasis. Studies in mice with targeted disruption for core circadian clock genes have revealed alterations in circadian rhythmicity as well as changes in sleep duration, sleep structure and EEG delta power. Clock-gene expression in brain areas outside the SCN, in particular the cerebral cortex, depends to a large extent on prior sleep-wake history. Evidence for effects of clock genes on sleep homeostasis has also been obtained in Drosophila and humans, pointing to a phylogenetically preserved pathway. These findings suggest that, while within the SCN clock genes are utilized to set internal time-of-day, in the forebrain the same feedback circuitry may be utilized to track time spent awake and asleep. The mechanisms by which clock-gene expression is coupled to the sleep-wake distribution could be through cellular energy charge whereby clock genes act as energy sensors. The data underscore the interrelationships between energy metabolism, circadian rhythmicity, and sleep regulation.


Subject(s)
Circadian Rhythm/genetics , Homeostasis/genetics , Homeostasis/physiology , Sleep/genetics , Sleep/physiology , Animals , Brain/physiology , Cell Cycle Proteins/genetics , Gene Expression , Humans , Intracellular Signaling Peptides and Proteins/genetics , Mice , Nuclear Proteins/genetics , Period Circadian Proteins , Phenotype , Signal Transduction , Transcription Factors/genetics , Transcription, Genetic , Wakefulness/genetics , Wakefulness/physiology
15.
Prev Vet Med ; 89(1-2): 1-7, 2009 May 01.
Article in English | MEDLINE | ID: mdl-19201499

ABSTRACT

This paper presents an analysis of a Salmonella control program for Dutch dairy herds. Salmonella control strategies were evaluated using a computer-based model consisting of an epidemiological module and an economics module. The epidemiological module is a state transition model of the infectivity of a herd, with the unit of analysis being the individual farm. The probability of a herd going from one state in the model to another state was derived from biological characteristics of Salmonella infections in dairy herds, and the presence or absence of risk factors. The economics module was based on partial budgeting. Control measures were modeled as influencing the risk factors. Amongst the measures considered were the prohibition of transporting potentially infectious animals and manure to farms, the culling of chronically infected animals, and herd management measures such as separate housing of groups of animal that differ in age. Alternative strategies, both compulsory and obligatory, were defined and evaluated concerning the reduction of prevalence of infected herds, the cost of a strategy, and cost-effectiveness. Results of the model suggested that a compulsory control strategy which included culling chronically infected animals and prohibiting the transport of potentially infected animals reduces the prevalence of Salmonella positive herds considerably, and was most cost-effective. Adding hygienic measures and a ban on the transport of animal manure further reduces prevalence, but only slightly, and with substantially more costs.


Subject(s)
Cattle Diseases/economics , Cattle Diseases/epidemiology , Dairying/economics , Salmonella Infections, Animal/economics , Salmonella Infections, Animal/epidemiology , Animals , Cattle , Cattle Diseases/prevention & control , Computer Simulation , Cost-Benefit Analysis , Dairying/methods , Dairying/standards , Female , Hygiene , Models, Biological , Netherlands/epidemiology , Prevalence , Probability , Risk Factors , Salmonella Infections, Animal/prevention & control
17.
Eur J Nucl Med Mol Imaging ; 35(9): 1602-7, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18491090

ABSTRACT

PURPOSE: The aim of this study was to investigate the influence of a computer-based decision support system (DSS) on performance and inter-observer variability of interpretations regarding ischaemia and infarction in myocardial perfusion scintigraphy (MPS). METHODS: Seven physicians independently interpreted 97 MPS studies, first without and then with the advice of a DSS. Four physicians had long experience and three had limited experience in the interpretation of MPS. Each study was interpreted regarding myocardial ischaemia and infarction in five myocardial regions. The patients had undergone a gated MPS using a 2-day stress/gated rest (99m)Tc sestamibi protocol. The gold standard used was the interpretations made by one experienced nuclear medicine specialist on the basis of all available clinical and image information. RESULTS: The sensitivity for ischaemia of the seven readers increased from 81% without the DSS to 86% with the DSS (p = 0.01). The increase in sensitivity was higher for the three inexperienced physicians (9%) than for the four experienced physicians (2%). There was no significant change in specificity between the interpretations. The interpretations of ischaemia made with the advice of the DSS showed less inter-observer variability than those made without advice. CONCLUSION: This study shows that a DSS can improve performance and reduces the inter-observer variability of interpretations in myocardial perfusion imaging. Both experienced and, especially, inexperienced physicians can improve their interpretation with the advice from such a system.


Subject(s)
Decision Support Systems, Clinical , Heart/diagnostic imaging , Myocardium/pathology , Radiographic Image Interpretation, Computer-Assisted/methods , Aged , Female , Humans , Male , Myocardial Infarction/diagnostic imaging , Neural Networks, Computer , Observer Variation , Perfusion , Radionuclide Imaging
18.
Br J Cancer ; 98(12): 1886-93, 2008 Jun 17.
Article in English | MEDLINE | ID: mdl-18506144

ABSTRACT

Sporadic cases of colorectal cancer are primarily initiated by gene mutations in members of the canonical Wnt pathway, ultimately resulting in beta-catenin stabilisation. Nevertheless, cells displaying nuclear beta-catenin accumulation are nonrandomly distributed throughout the tumour mass and preferentially localise along the invasive front where parenchymal cells are in direct contact with the stromal microenvironment. Here, we discuss the putative role played by stromal cell types in regulating beta-catenin intracellular accumulation in a paracrine fashion. As such, the tumour microenvironment is likely to maintain the cancer stem cell phenotype in a subset of cells, thus mediating invasion and metastasis.


Subject(s)
Colorectal Neoplasms/pathology , Neoplastic Stem Cells/pathology , Stromal Cells/pathology , beta Catenin/metabolism , Adipocytes/cytology , Colorectal Neoplasms/immunology , Colorectal Neoplasms/metabolism , Humans , Neoplasm Invasiveness , Neoplasm Metastasis , Neoplastic Stem Cells/metabolism , Stromal Cells/metabolism
19.
Eur J Nucl Med Mol Imaging ; 35(4): 851-85, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18224320

ABSTRACT

Radionuclide imaging of cardiac function represents a number of well-validated techniques for accurate determination of right (RV) and left ventricular (LV) ejection fraction (EF) and LV volumes. These first European guidelines give recommendations for how and when to use first-pass and equilibrium radionuclide ventriculography, gated myocardial perfusion scintigraphy, gated PET, and studies with non-imaging devices for the evaluation of cardiac function. The items covered are presented in 11 sections: clinical indications, radiopharmaceuticals and dosimetry, study acquisition, RV EF, LV EF, LV volumes, LV regional function, LV diastolic function, reports and image display and reference values from the literature of RVEF, LVEF and LV volumes. If specific recommendations given cannot be based on evidence from original, scientific studies, referral is given to "prevailing or general consensus". The guidelines are designed to assist in the practice of referral to, performance, interpretation and reporting of nuclear cardiology studies for the evaluation of cardiac performance.


Subject(s)
Heart Function Tests , Heart/diagnostic imaging , Radioisotopes , Europe , Heart/physiology , Humans , Myocardial Infarction/diagnostic imaging , Nuclear Medicine/standards , Radionuclide Imaging , Ventricular Function, Left
20.
Tijdschr Diergeneeskd ; 132(23): 912-7, 2007 Dec 01.
Article in Dutch | MEDLINE | ID: mdl-18085174

ABSTRACT

Q fever, a zoonosis caused by the gram-negative bacterium Coxiella burnetii, occurs worldwide and affects both humans and animals. Ruminants are considered to be the main source of infection of humans, with the main route of infection being through inhalation of the organism of fine-particle aerosols. Abortion is the main clinical sign in ruminants. During and after abortion, large quantities of the bacterium are shed via the placenta and other vaginal secretions. The bacterium may also be present in faeces and milk. The bacterium can survive for a long time in the environment after shedding and can be spread over long distances. Seroprevalence among cattle is rather high in the Netherlands and in many other countries. Infection is diagnosed by detecting antibodies against the bacterium or the bacterium itself by means of a PCR method. The efficacy of using antibiotics or vaccines for treatment or prevention of the disease in cattle is still unclear and there are currently no effective disease control programmes.


Subject(s)
Abortion, Veterinary/microbiology , Antibodies, Bacterial/blood , Bacterial Vaccines/immunology , Coxiella burnetii/pathogenicity , Q Fever/veterinary , Air Microbiology , Animals , Cattle , Coxiella burnetii/immunology , Female , Goats , Humans , Placenta/microbiology , Pregnancy , Pregnancy Complications, Infectious/microbiology , Pregnancy Complications, Infectious/veterinary , Prevalence , Q Fever/diagnosis , Q Fever/epidemiology , Q Fever/transmission , Sheep , Vagina/microbiology , Zoonoses
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