122 research outputs found
Rapid Brain Cooling in Intubated Pigs through Nasal Flushing with Oxygen: Prevention of Brain Hyperthermia
Local cooling of the brain by the respiratory air is found in many animal species. The mechanism is based on cooling of the nasal vein blood and heat transfer in the cavernous sinus/carotid artery complex and is therefore not active in anaesthetised, intubated animals. The present experiment was made to investigate the effects of oxygen flushing of the nasal cavities in such animals. Nine anaesthetised, intubated male pigs were used. The temperatures in the third ventricle and rectum were measured continuously. Oxygen was infused into the nasal cavities during 10 min periods interrupted by 10 min without flow. The nasal oxygen flow constantly induced a rapid, reversible and flow dependant decrease in brain temperature: 0.25°C ± 0.04, (n = 2) (mean ± SD, n) at <4 l/min; 1.35°C ± 0.78, (n = 20) at 4–6 l/min; and 1.44°C ± 0.62, (n = 6) at >6 l/min. The ventricle temperature decreased 0.59°C ± 0.23, (n = 8) when the animals were transferred to spontaneous respiration and the tracheal tube removed. It may be possible to protect the brain in intubated animals and humans from heat-induced damages by establishment of nasal flushing
Eating patterns and overweight in 9- to 10-year-old children in Telemark County, Norway: a cross-sectional study
Background/Objectives: Increasing prevalence of overweight in children is a growing health problem. The aim of this study was to describe the eating patterns of 9-to 10-year-old schoolchildren, and to investigate the relationship between overweight and eating patterns. Subjects/Methods: We recruited 1045 children for a cross-sectional study in Telemark County, Norway. The children's food, snacking and meal frequencies were reported by their parents using a retrospective food frequency questionnaire. Height and weight were measured by health professionals, and body mass index categories were calculated using international standard cutoff points (International Obesity Task Force values). Complete data were obtained for 924 children. Four distinct eating patterns were identified using principal component analysis. We used multiple logistic regression and calculated odds ratios (ORs) with 95% confidence intervals (CIs) for being overweight, and adjusted for parental characteristics and physical activity levels of the children (aORs). Results: Parental characteristics and physical activity were associated with both obesity and eating patterns. Children adhering to a 'junk/convenient' eating pattern had a significantly lower likelihood of being overweight (aOR: 0.6; 95% CI: 0.4, 0.9), whereas children adhering to a 'varied Norwegian' or a 'dieting' eating pattern had a significantly higher likelihood of being overweight (respective values: aOR: 2.1; 95% CI: 1.3, 3.2; aOR: 2.2; 95% CI: 1.4, 3.4). No association with overweight was seen for a 'snacking pattern'. Conclusions: The main finding was that, although family characteristics influenced both the prevalence of overweight and overall dietary behaviour, independent associations were evident between eating patterns and overweight, indicating parental modification of the diets of overweight children
Biphasic Electrical Currents Stimulation Promotes both Proliferation and Differentiation of Fetal Neural Stem Cells
The use of non-chemical methods to differentiate stem cells has attracted
researchers from multiple disciplines, including the engineering and the
biomedical fields. No doubt, growth factor based methods are still the most
dominant of achieving some level of proliferation and differentiation control -
however, chemical based methods are still limited by the quality, source, and
amount of the utilized reagents. Well-defined non-chemical methods to
differentiate stem cells allow stem cell scientists to control stem cell biology
by precisely administering the pre-defined parameters, whether they are
structural cues, substrate stiffness, or in the form of current flow. We have
developed a culture system that allows normal stem cell growth and the option of
applying continuous and defined levels of electric current to alter the cell
biology of growing cells. This biphasic current stimulator chip employing ITO
electrodes generates both positive and negative currents in the same culture
chamber without affecting surface chemistry. We found that biphasic electrical
currents (BECs) significantly increased the proliferation of fetal neural stem
cells (NSCs). Furthermore, BECs also promoted the differentiation of fetal NSCs
into neuronal cells, as assessed using immunocytochemistry. Our results clearly
show that BECs promote both the proliferation and neuronal differentiation of
fetal NSCs. It may apply to the development of strategies that employ NSCs in
the treatment of various neurodegenerative diseases, such as Alzheimer's
and Parkinson's diseases
Biphasic Electrical Currents Stimulation Promotes both Proliferation and Differentiation of Fetal Neural Stem Cells
The use of non-chemical methods to differentiate stem cells has attracted
researchers from multiple disciplines, including the engineering and the
biomedical fields. No doubt, growth factor based methods are still the most
dominant of achieving some level of proliferation and differentiation control -
however, chemical based methods are still limited by the quality, source, and
amount of the utilized reagents. Well-defined non-chemical methods to
differentiate stem cells allow stem cell scientists to control stem cell biology
by precisely administering the pre-defined parameters, whether they are
structural cues, substrate stiffness, or in the form of current flow. We have
developed a culture system that allows normal stem cell growth and the option of
applying continuous and defined levels of electric current to alter the cell
biology of growing cells. This biphasic current stimulator chip employing ITO
electrodes generates both positive and negative currents in the same culture
chamber without affecting surface chemistry. We found that biphasic electrical
currents (BECs) significantly increased the proliferation of fetal neural stem
cells (NSCs). Furthermore, BECs also promoted the differentiation of fetal NSCs
into neuronal cells, as assessed using immunocytochemistry. Our results clearly
show that BECs promote both the proliferation and neuronal differentiation of
fetal NSCs. It may apply to the development of strategies that employ NSCs in
the treatment of various neurodegenerative diseases, such as Alzheimer's
and Parkinson's diseases
Mimicking the Neurotrophic Factor Profile of Embryonic Spinal Cord Controls the Differentiation Potential of Spinal Progenitors into Neuronal Cells
Recent studies have indicated that the choice of lineage of neural progenitor cells is determined, at least in part, by environmental factors, such as neurotrophic factors. Despite extensive studies using exogenous neurotrophic factors, the effect of endogenous neurotrophic factors on the differentiation of progenitor cells remains obscure. Here we show that embryonic spinal cord derived-progenitor cells express both ciliary neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF) mRNA before differentiation. BDNF gene expression significantly decreases with their differentiation into the specific lineage, whereas CNTF gene expression significantly increases. The temporal pattern of neurotrophic factor gene expression in progenitor cells is similar to that of the spinal cord during postnatal development. Approximately 50% of spinal progenitor cells differentiated into astrocytes. To determine the effect of endogenous CNTF on their differentiation, we neutralized endogenous CNTF by administration of its polyclonal antibody. Neutralization of endogenous CNTF inhibited the differentiation of progenitor cells into astrocytes, but did not affect the numbers of neurons or oligodendrocytes. Furthermore, to mimic the profile of neurotrophic factors in the spinal cord during embryonic development, we applied BDNF or neurotrophin (NT)-3 exogenously in combination with the anti-CNTF antibody. The exogenous application of BDNF or NT-3 promoted the differentiation of these cells into neurons or oligodendrocytes, respectively. These findings suggest that endogenous CNTF and exogenous BDNF and NT-3 play roles in the differentiation of embryonic spinal cord derived progenitor cells into astrocytes, neurons and oligodendrocytes, respectively
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Corporate tax: what do stakeholders expect?
Motivated by the ongoing controversy surrounding corporate tax, this article presents a study that explores stakeholder expectations of corporate tax in the context of UK business. We conduct a qualitative analysis of in-depth interviews with representatives of community groups (NGOs/think tanks and special interest groups), as well as interviews with those representing business groups (business leaders and industry representatives). We then identify eight themes that together describe “what” companies need to do, “how” they need to do it, and “why” they need to do it, if they wish to appeal to a wide group of interested parties. We discuss our findings based on the corporate social responsibility literature and propose novel ways for community groups and business groups to connect on the topic of corporate tax, suggesting opportunities and themes for dialogue and potential steps to co-create solutions in a stakeholder society
Metabolism before, during and after anaesthesia in colic and healthy horses
<p>Abstract</p> <p>Background</p> <p>Many colic horses are compromised due to the disease state and from hours of starvation and sometimes long trailer rides. This could influence their muscle energy reserves and affect the horses' ability to recover. The principal aim was to follow metabolic parameter before, during, and up to 7 days after anaesthesia in healthy horses and in horses undergoing abdominal surgery due to colic.</p> <p>Methods</p> <p>20 healthy horses given anaesthesia alone and 20 colic horses subjected to emergency abdominal surgery were anaesthetised for a mean of 228 minutes and 183 minutes respectively. Blood for analysis of haematology, electrolytes, cortisol, creatine kinase (CK), free fatty acids (FFA), glycerol, glucose and lactate was sampled before, during, and up to 7 days after anaesthesia. Arterial and venous blood gases were obtained before, during and up to 8 hours after recovery. Gluteal muscle biopsy specimens for biochemical analysis of muscle metabolites were obtained at start and end of anaesthesia and 1 h and 1 day after recovery.</p> <p>Results</p> <p>Plasma cortisol, FFA, glycerol, glucose, lactate and CK were elevated and serum phosphate and potassium were lower in colic horses before anaesthesia. Muscle adenosine triphosphate (ATP) content was low in several colic horses. Anaesthesia and surgery resulted in a decrease in plasma FFA and glycerol in colic horses whereas levels increased in healthy horses. During anaesthesia muscle and plasma lactate and plasma phosphate increased in both groups. In the colic horses plasma lactate increased further after recovery. Plasma FFA and glycerol increased 8 h after standing in the colic horses. In both groups, plasma concentrations of CK increased and serum phosphate decreased post-anaesthesia. On Day 7 most parameters were not different between groups. Colic horses lost on average 8% of their initial weight. Eleven colic horses completed the study.</p> <p>Conclusion</p> <p>Colic horses entered anaesthesia with altered metabolism and in a negative oxygen balance. Muscle oxygenation was insufficient during anaesthesia in both groups, although to a lesser extent in the healthy horses. The post-anaesthetic period was associated with increased lipolysis and weight loss in the colic horses, indicating a negative energy balance during the first week post-operatively.</p
Associations between reporting of cancer alarm symptoms and socioeconomic and demographic determinants: a population-based, cross-sectional study
Are safety data sheets for cleaning products used in Norway a factor contributing to the risk of workers exposure to chemicals?
Altered excitatory-inhibitory balance within somatosensory cortex is associated with enhanced plasticity and pain sensitivity in a mouse model of multiple sclerosis
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