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Sample records for brain tissue oxygen

  1. Brain Tissue Oxygen Monitoring in Neurocritical Care.

    Science.gov (United States)

    De Georgia, Michael A

    2015-12-01

    Brain injury results from ischemia, tissue hypoxia, and a cascade of secondary events. The cornerstone of neurocritical care management is optimization and maintenance of cerebral blood flow (CBF) and oxygen and substrate delivery to prevent or attenuate this secondary damage. New techniques for monitoring brain tissue oxygen tension (PtiO2) are now available. Brain PtiO2 reflects both oxygen delivery and consumption. Brain hypoxia (low brain PtiO2) has been associated with poor outcomes in patients with brain injury. Strategies to improve brain PtiO2 have focused mainly on increasing oxygen delivery either by increasing CBF or by increasing arterial oxygen content. The results of nonrandomized studies comparing brain PtiO2-guided therapy with intracranial pressure/cerebral perfusion pressure-guided therapy, while promising, have been mixed. More studies are needed including prospective, randomized controlled trials to assess the true value of this approach. The following is a review of the physiology of brain tissue oxygenation, the effect of brain hypoxia on outcome, strategies to increase oxygen delivery, and outcome studies of brain PtiO2-guided therapy in neurocritical care.

  2. Real-time changes in brain tissue oxygen during endovascular treatment of cerebral vasospasm

    DEFF Research Database (Denmark)

    Rasmussen, Rune; Bache, Søren; Stavngaard, Trine;

    2015-01-01

    pressure (PtiO₂) in target parenchyma. However, during the intervention, dangerously low levels of brain tissue oxygen, leading to cerebral infarction, may occur. Thus, no clinical improvement was seen in two of the patients and a dramatic worsening was observed in the third patient. Because the decrease...... minute-by-minute changes in brain tissue oxygen during balloon angioplasty and intraarterial administration of vasodilators in three patients.Our results confirm that endovascular intervention is capable of not only resolving angiographic vasospasm, but also of normalizing values of brain tissue oxygen...... in brain tissue oxygen was seen after administration of vasopressor agents, this may be a contributing factor....

  3. Brain Tissue Oxygen: In Vivo Monitoring with Carbon Paste Electrodes

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    John P. Lowry

    2005-11-01

    Full Text Available In this communication we review selected experiments involving the use ofcarbon paste electrodes (CPEs to monitor and measure brain tissue O2 levels in awakefreely-moving animals. Simultaneous measurements of rCBF were performed using the H2clearance technique. Voltammetric techniques used include both differential pulse (O2 andconstant potential amperometry (rCBF. Mild hypoxia and hyperoxia produced rapidchanges (decrease and increase respectively in the in vivo O2 signal. Neuronal activation(tail pinch and stimulated grooming produced similar increases in both O2 and rCBFindicating that CPE O2 currents provide an index of increases in rCBF when such increasesexceed O2 utilization. Saline injection produced a transient increase in the O2 signal whilechloral hydrate produced slower more long-lasting changes that accompanied the behavioralchanges associated with anaesthesia. Acetazolamide increased O2 levels through an increasein rCBF.

  4. Improvement of Brain Tissue Oxygenation by Inhalation of Carbogen

    DEFF Research Database (Denmark)

    Ashkanian, M.; Borghammer, P.; Gjedde, A.;

    2008-01-01

    Hyperoxic therapy for cerebral ischemia is suspected to reduce cerebral blood flow (CBF), due to the vasoconstrictive effect of oxygen on cerebral arterioles. We hypothesized that vasodilation predominates when 5% CO(2) is added to the inhaled oxygen (carbogen). Therefore, we used positron emission...... tomography (PET) to measure CBF and cerebral metabolic rate of oxygen (CMRO(2)) during inhalation of test gases (O(2), CO(2), carbogen and atmospheric air) in 10 healthy volunteers. Arterial blood gases were recorded during administration of each gas. The data were analyzed with volume-of-interest and voxel......-based statistical methods. Inhalation of CO(2) or carbogen significantly increased global CBF, whereas pure oxygen decreased global CBF. The CMRO(2) generally remained unchanged, except in white matter during oxygen inhalation relative to condition of atmospheric air inhalation. The volume-of-interest results were...

  5. Brain tissue partial pressure of oxygen predicts the outcome of severe traumatic brain injury under mild hypothermia treatment

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    Sun H

    2016-08-01

    Full Text Available Hongtao Sun,1,* Maohua Zheng,2,* Yanmin Wang,1 Yunfeng Diao,1 Wanyong Zhao,1 Zhengjun Wei1 1Sixth Department of Neurosurgery, Affiliated Hospital of Logistics University of People’s Armed Police Force, Tianjin, 2Department of Neurosurgery, The First Hospital of Lanzhou University, Lanzhou, People’s Republic of China *These authors contributed equally to this work Objective: The aim of this study was to investigate the clinical significance and changes of brain tissue partial pressure of oxygen (PbtO2 in the course of mild hypothermia treatment (MHT for treating severe traumatic brain injury (sTBI. Methods: There were 68 cases with sTBI undergoing MHT. PbtO2, intracranial pressure (ICP, jugular venous oxygen saturation (SjvO2, and cerebral perfusion pressure (CPP were continuously monitored, and clinical outcomes were evaluated using the Glasgow Outcome Scale score. Results: Of 68 patients with sTBI, PbtO2, SjvO2, and CPP were obviously increased, but decreased ICP level was observed throughout the MHT. PbtO2 and ICP were negatively linearly correlated, while there was a positive linear correlation between PbtO2 and SjvO2. Monitoring CPP and SjvO2 was performed under normal circumstances, and a large proportion of patients were detected with low PbtO2. Decreased PbtO2 was also found after MHT. Conclusion: Continuous PbtO2 monitoring could be introduced to evaluate the condition of regional cerebral oxygen metabolism, thereby guiding the clinical treatment and predicting the outcome. Keywords: severe traumatic brain injury, hypothermia, brain tissue partial pressure of oxygen, therapy

  6. Effects of acetazolamide on cerebral blood flow and brain tissue oxygenation

    DEFF Research Database (Denmark)

    Lassen, N A; Friberg, L; Kastrup, J;

    1987-01-01

    decreased gradually to 70% of the control value, indicating hyperventilation. At sea level hyperventilation will not increase brain oxygenation significantly in normal man, as the arterial oxygen content only increases minimally, while CBF is unchanged. At high altitude the beneficial effects...... of acetazolamide on the symptoms of acute mountain sickness may well be due to an improved oxygen supply to the brain, as hyperventilation will, at the low ambient PO2, cause a significant increase of the arterial oxygen content, while CBF presumably is unaffected by the drug. During hypoxia at high altitude...... the overall effect of prolonged acetazolamide treatment may thus be equivalent to a descent by several hundred metres....

  7. Effect of Short Periods of Normobaric Hyperoxia on Local Brain Tissue Oxygenation and Cerebrospinal Fluid Oxidative Stress Markers in Severe Traumatic Brain Injury

    OpenAIRE

    Puccio, Ava M.; Hoffman, Leslie A.; Bayir, Hülya; Zullo, Thomas G.; Fischer, Michael; Darby, Joseph; Alexander, Sheila; Dixon, C. Edward; Okonkwo, David O.; Kochanek, Patrick M.

    2009-01-01

    Preliminary evidence suggests local brain tissue oxygenation (PbtO2) values of ≤15 mm Hg following severe traumatic brain injury (TBI) represent brain tissue hypoxia. Accordingly, many neurotrauma units attempt to maintain PbtO2 ≥20 mm Hg to avoid hypoxia. This study tested the impact of a short (2 h) trial of normobaric hyperoxia on measures of oxidative stress. We hypothesized this treatment would positively affect cerebral oxygenation but negatively affect the cellular environment via oxid...

  8. Continuous-wave near-infrared spectroscopy is not related to brain tissue oxygen tension.

    Science.gov (United States)

    Kerz, Thomas; Beyer, Christian; Huthmann, Alexandra; Kalasauskas, Darius; Amr, Amr Nimer; Boor, Stephan; Welschehold, Stefan

    2016-10-01

    Near-infrared spectroscopy (NIRS) has gained acceptance for cerebral monitoring, especially during cardiac surgery, though there are few data showing its validity. We therefore aimed to correlate invasive brain tissue oxygen measurements (PtiO2) with the corresponding NIRS-values (regional oxygen saturation, rSO2). We also studied whether NIRS was able to detect ischemic events, defined as a PtiO2-value of wave NIRS. PtiO2-correlation with corresponding NIRS-values was calculated. We found no correlation between PtiO2- and NIRS-readings. Measurement of rSO2 was no better than flipping a coin in the detection of cerebral ischemia when a commonly agreed ischemic PtiO2 cut-off value of wave-NIRS was unable to reliably detect ischemic cerebral episodes, defined as a PtiO2 value <15 mmHg. Displayed NIRS-values did not correlate with invasively measured PtiO2-values. CW-NIRS should not be used for the detection of cerebral ischemia. PMID:26289038

  9. High dose Erythropoietin increases Brain Tissue Oxygen Tension in Severe Vasospasm after Subarachnoid Hemorrhage

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    Helbok Raimund

    2012-06-01

    Full Text Available Abstract Background Vasospasm-related delayed cerebral ischemia (DCI significantly impacts on outcome after aneurysmal subarachnoid hemorrhage (SAH. Erythropoietin (EPO may reduce the severity of cerebral vasospasm and improve outcome, however, underlying mechanisms are incompletely understood. In this study, the authors aimed to investigate the effect of EPO on cerebral metabolism and brain tissue oxygen tension (PbtO2. Methods Seven consecutive poor grade SAH patients with multimodal neuromonitoring (MM received systemic EPO therapy (30.000 IU per day for 3 consecutive days for severe cerebral vasospasm. Cerebral perfusion pressure (CPP, mean arterial blood pressure (MAP, intracranial pressure (ICP, PbtO2 and brain metabolic changes were analyzed during the next 24 hours after each dose given. Statistical analysis was performed with a mixed effects model. Results A total of 22 interventions were analyzed. Median age was 47 years (32–68 and 86 % were female. Three patients (38 % developed DCI. MAP decreased 2 hours after intervention (P btO2 significantly increased over time (P  Conclusions EPO increases PbtO2 in poor grade SAH patients with severe cerebral vasospasm. The effect on outcome needs further investigation.

  10. BRAIN FUNCTIONAL IMAGING BASED ON BRAIN TISSUE OXYGEN CONTENT VIA MAGNETIC RESONANCE

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    M.A OGHABIAN

    2003-03-01

    Full Text Available Introduction: FMRI is a new approach in MRI to provide functional data of human brain activities. Some methods such as BOLD contrast, perfusion imaging, diffusion imaging, and spectroscopy in MRI have used to yield functional images. Material and Methods: This research was performed in imaging center of IMAM KHOMEINI hospital in TEHRAN in 1997. The experiments were performed on a conventional 1.5- T picker MR instrument, using a standard head coil. CE – FAST gradient echo images were obtained (TR=100, TE = 35, 128*256 matrix, 10 mm slice, FOV = 250 mm, F.A =25 Degree, NEX = 1, 13 s per image. Images were obtained during sensory - motor stimulation by pressing fingers to each other, coronal oblique images were acquired through central sulcus (precentral gyrus where the related sensory cortex is. Then, the Images were transferred to personal computers in order to eliminate noise and highlight the functional differences. These images were processed by various mathematical methods such as subtraction and student T- test. Results: Although some changes were seen in functional area, there were not significant results by the conventional system protocols. Some new protocols were designed and implemented to increase the sensitivity of the system to functional changes. Discussion: However, more research needs to be done in the future to obtain faster and more efficient techniques and in regard to clinical applications of the method.

  11. Brain tissue oxygen-based therapy and outcome after severe traumatic brain injury: a systematic literature review.

    Science.gov (United States)

    Nangunoori, Raj; Maloney-Wilensky, Eileen; Stiefel, Michael; Park, Soojin; Andrew Kofke, W; Levine, Joshua M; Yang, Wei; Le Roux, Peter D

    2012-08-01

    Observational clinical studies demonstrate that brain hypoxia is associated with poor outcome after severe traumatic brain injury (TBI). In this study, available medical literature was reviewed to examine whether brain tissue oxygen (PbtO2)-based therapy is associated with improved patient outcome after severe TBI. Clinical studies published between 1993 and 2010 that compared PbtO2-based therapy combined with intracranial and cerebral perfusion pressure (ICP/CPP)-based therapy to ICP/CPP-based therapy alone were identified from electronic databases, Index Medicus, bibliographies of pertinent articles, and expert consultation. For analysis, each selected paper had to have adequate data to determine odds ratios (ORs) and confidence intervals (CIs) of outcome described by the Glasgow outcome score (GOS). Seven studies that compared ICP/CPP and PbtO2- to ICP/CPP-based therapy were identified. There were no randomized studies and no comparison studies in children. Four studies, published in 2003, 2009, and 2010 that included 491 evaluable patients were used in the final analysis. Among patients who received PbtO2-based therapy, 121(38.8%) had unfavorable and 191 (61.2%) had a favorable outcome. Among the patients who received ICP/CPP-based therapy 104 (58.1%) had unfavorable and 75 (41.9%) had a favorable outcome. Overall PbtO2-based therapy was associated with favorable outcome (OR 2.1; 95% CI 1.4-3.1). Summary results suggest that combined ICP/CPP- and PbtO2-based therapy is associated with better outcome after severe TBI than ICP/CPP-based therapy alone. Cross-organizational practice variances cannot be controlled for in this type of review and so we cannot answer whether PbtO2-based therapy improves outcome. However, the potentially large incremental value of PbtO2-based therapy provides justification for a randomized clinical trial.

  12. Measuring tissue oxygenation

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    Soyemi, Olusola O. (Inventor); Soller, Babs R. (Inventor); Yang, Ye (Inventor)

    2009-01-01

    Methods and systems for calculating tissue oxygenation, e.g., oxygen saturation, in a target tissue are disclosed. In some embodiments, the methods include: (a) directing incident radiation to a target tissue and determining reflectance spectra of the target tissue by measuring intensities of reflected radiation from the target tissue at a plurality of radiation wavelengths; (b) correcting the measured intensities of the reflectance spectra to reduce contributions thereto from skin and fat layers through which the incident radiation propagates; (c) determining oxygen saturation in the target tissue based on the corrected reflectance spectra; and (d) outputting the determined value of oxygen saturation.

  13. In vivo evidence of methamphetamine induced attenuation of brain tissue oxygenation as measured by EPR oximetry

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, John, E-mail: jmweaver@salud.unm.edu [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Yang, Yirong [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Purvis, Rebecca [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Neurology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Weatherwax, Theodore [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Rosen, Gerald M. [Center for Biomedical Engineering and Technology, University of Maryland, Baltimore, MD 21201 (United States); Center for EPR Imaging In Vivo Physiology, University of Maryland, Baltimore, MD 21201 (United States); Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201 (United States); Liu, Ke Jian [Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Department of Neurology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States)

    2014-03-01

    Abuse of methamphetamine (METH) is a major and significant societal problem in the US, as a number of studies have suggested that METH is associated with increased cerebrovascular events, hemorrhage or vasospasm. Although cellular and molecular mechanisms involved in METH-induced toxicity are not completely understood, changes in brain O{sub 2} may play an important role and contribute to METH-induced neurotoxicity including dopaminergic receptor degradation. Given that O{sub 2} is the terminal electron acceptor for many enzymes that are important in brain function, the impact of METH on brain tissue pO{sub 2}in vivo remains largely uncharacterized. This study investigated striatal tissue pO{sub 2} changes in male C57BL/6 mice (16–20 g) following METH administration using EPR oximetry, a highly sensitive modality to measure pO{sub 2}in vivo, in situ and in real time. We demonstrate that 20 min after a single injection of METH (8 mg/kg i.v.), the striatal pO{sub 2} was reduced to 81% of the pretreatment level and exposure to METH for 3 consecutive days further attenuated striatal pO{sub 2} to 64%. More importantly, pO{sub 2} did not recover fully to control levels even 24 h after administration of a single dose of METH and continual exposure to METH exacerbates the condition. We also show a reduction in cerebral blood flow associated with a decreased brain pO{sub 2} indicating an ischemic condition. Our findings suggests that administration of METH can attenuate brain tissue pO{sub 2}, which may lead to hypoxic insult, thus a risk factor for METH-induced brain injury and the development of stroke in young adults. - Highlights: • Explored striatal tissue pO{sub 2}in vivo after METH administration by EPR oximetry. • pO{sub 2} was reduced by 81% after a single dose and 64% after 3 consecutive daily doses. • pO{sub 2} did not recover fully to control levels even 24 h after a single dose. • Decrease in brain tissue pO{sub 2} may be associated with a decrease in

  14. Fluctuation of Brain Tissue Oxygen Partial Pressure: A Biochemical Landmark in the Arctic Ground Squirrel's Spontaneous Arousal

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    Yi L. Ma

    2011-01-01

    Full Text Available Hibernation in the Arctic ground Squirrel (AGS is a regulated, adaptive response to arctic environmental conditions. Problem statement: Regional brain Blood Flow (rCBF has been observed to increase dramatically during arousal in hibernators. However, the real time dynamic change in PtO2 during arousal has not been studied, we hypothesized that PtO2 is Interdependent of Tbrain and a key component in the arousal process. Approach: Simultaneous in vivo measurements of PtO2 and brain temperature (Tbrain in conjunction with oxygen consumption (V02 were conducted in the striatum of non-sedated, non-anesthetized Arctic ground squirrels during spontaneous arousal from hibernation. Results: A dramatic fluctuation of brain tissue oxygen partial pressure (PtO2 is associated with the complex phenomena of spontaneous arousal. In this study, we observed that: (1 a PtO2 elevation precedes changes in Tbrain and V02; (2 PtO2 changes do not correlate with changes in V02 during arousal and (3, endogenous O2 shift from O2 enriched blood to brain in hibernating AGS induces an arousal with the pharmaceutical chemical, efaproxiral (RSR-13. Conclusion: The four turning points of PtO2 appearing at different Tbrain during arousal suggest that changes in PtO2 are Tbrain interdependent and support the concept that arousal from hibernation is complex process invoking different feedbacks.

  15. Study on changes of partial pressure of brain tissue oxygen and brain temperature in acute phase of severe head injury during mild hypothermia therapy

    Institute of Scientific and Technical Information of China (English)

    朱岩湘; 姚杰; 卢尚坤; 章更生; 周关仁

    2003-01-01

    Objective: To study the changes of partial pressure of brain tissue oxygen (PbtO2) and brain temperature in acute phase of severe head injury during mild hypothermia therapy and the clinical significance.Methods: One hundred and sixteen patients with severe head injury were selected and divided into a mild hypothermia group (n=58), and a control group (n=58) according to odd and even numbers of hospitalization. While mild hypothermia therapy was performed PbtO2 and brain temperature were monitored for 1-7 days (mean=86 hours), simultaneously, the intracranial pressure, rectum temperature, cerebral perfusion pressure, PaO2 and PaCO2 were also monitored. The patients were followed up for 6 months and the prognosis was evaluated with GOS (Glasgow outcome scale).Results: The mean value of PbtO2 within 24 hour monitoring in the 116 patients was 13.7 mm Hg±4.94 mm Hg, lower than the normal value (16 mm Hg±40 mm Hg) The time of PbtO2 recovering to the normal value in the mild hypothermia group was shortened by 10±4.15 hours compared with the control group (P<0.05). The survival rate of the mild hypothermia group was 60.43%, higher than that of the control group (46.55%). After the recovery of the brain temperature, PbtO2 increased with the rise of the brain temperature. Conclusions: Mild hypothermia can improve the survival rate of severe head injury. The technique of monitoring PbtO2 and the brain temperature is safe and reliable, and has important clinical significance in judging disease condition and instructing clinical therapy.

  16. Feasibility of mapping the tissue mass corrected bioscale of cerebral metabolic rate of oxygen consumption using 17-oxygen and 23-sodium MR imaging in a human brain at 9.4 T.

    Science.gov (United States)

    Atkinson, Ian C; Thulborn, Keith R

    2010-06-01

    The reduction of molecular oxygen to water is the final step of oxidative phosphorylation that couples adenosine triphosphate production to the reoxidation of reducing equivalents formed during the oxidation of glucose to carbon dioxide. This coupling makes the cerebral metabolic rate of oxygen consumption (CMRO(2)) an excellent reflection of the metabolic health of the brain. A multi-nuclear magnetic resonance (MR) imaging based method for CMRO(2) mapping is proposed. Oxygen consumption is determined by applying a new three-phase metabolic model for water generation and clearance to the changing 17-oxygen ((17)O) labeled water MR signal measured using quantitative (17)O MR imaging during inhalation of (17)O-enriched oxygen gas. These CMRO(2) data are corrected for the regional brain tissue mass computed from quantitative 23-sodium MR imaging of endogenous tissue sodium ions to derive quantitative results of oxygen consumption in micromoles O(2)/g tissue/minute that agree with literature results reported from positron emission tomography. The proposed technique is demonstrated in the human brain using a 9.4 T MR scanner optimized for human brain imaging.

  17. A Prospective Randomized Study of Brain Tissue Oxygen Pressure-Guided Management in Moderate and Severe Traumatic Brain Injury Patients

    Directory of Open Access Journals (Sweden)

    Chien-Min Lin

    2015-01-01

    Full Text Available The purpose of this study was to compare the effect of PbtO2-guided therapy with traditional intracranial pressure- (ICP- guided treatment on the management of cerebral variables, therapeutic interventions, survival rates, and neurological outcomes of moderate and severe traumatic brain injury (TBI patients. From 2009 to 2010, TBI patients with a Glasgow coma scale 20 mmHg, and 27 patients were treated with ICP-guided therapy (ICP 60 mmHg in the neurosurgical intensive care unit (NICU; demographic characteristics were similar across groups. The survival rate in the PbtO2-guided group was also significantly increased at 3 and 6 months after injury. Moreover, there was a significant correlation between the PbtO2 signal and Glasgow outcome scale-extended in patients from 1 to 6 months after injury. This finding demonstrates that therapy directed by PbtO2 monitoring is valuable for the treatment of patients with moderate and severe TBI and that increasing PaO2 to 150 mmHg may be efficacious for preventing cerebral hypoxic events after brain trauma.

  18. Carbogen inhalation increases oxygen transport to hypoperfused brain tissue in patients with occlusive carotid artery disease: increased oxygen transport to hypoperfused brain

    DEFF Research Database (Denmark)

    Ashkanian, Mahmoud; Gjedde, Albert; Mouridsen, Kim;

    2009-01-01

    Hyperoxic therapy for cerebral ischemia reduces cerebral blood flow (CBF) principally from the vasoconstrictive effect of oxygen on cerebral arterioles. Based on a recent study in normal volunteers, we now claim that the vasodilatory effect of carbon dioxide predominates when 5% CO(2) is added...... to inhaled oxygen (the mixture known as carbogen). In the present study, we measured CBF by positron emission tomography (PET) during inhalation of test gases (O(2), carbogen, and atmospheric air) in healthy volunteers (n = 10) and in patients with occlusive carotid artery disease (n = 6). Statistical...... comparisons by an additive ANOVA model showed that carbogen significantly increased CBF by 7.51 + or - 1.62 ml/100 g/min while oxygen tended to reduce it by -3.22 + or - 1.62 ml/100 g/min. A separate analysis of the hemisphere contralateral to the hypoperfused hemisphere showed that carbogen significantly...

  19. Effect of mild hypothermia on partial pressure of oxygen in brain tissue and brain temperature in patients with severe head injury

    Institute of Scientific and Technical Information of China (English)

    张赛; 只达石; 林欣; 尚彦国; 牛玉德

    2002-01-01

    Objective: To study the changes of partial pressure of oxygen in brain tissue (PbtO2) and brain temperature (BT) in patients in acute phase of severe head injury, and to study the effect of mild hypothermia on PbtO2 and BT.   Methods: The PbtO2 and the BT of 18 patients with severe head injury were monitored, and the patients were treated with mild hypothermia within 20 hours after injury. The rectal temperature (RT) of the patients was kept on 31.5-34.9℃ for 1-7 days (57.7 hours±28.4 hours averagely), simultaneously, the indexes of PbtO2 and BT were monitored for 1-5 days (with an average of 54.8 hours±27.0 hours). According to Glasgow Outcome Scale (GOS), the prognosis of the patients was evaluated at 6 months after injury.   Results: Within 24 hours after severe head injury, the PbtO2 was significantly lower (9.6 mm Hg±6.8 mm Hg, 1 mm Hg=0.133 kPa) than the normal value (16-40 mm Hg). After treatment of mild hypothermia, the mean PbtO2 increased to 28.7 mm Hg±8.8 mm Hg during the first 24 hours, and the PbtO2 was still maintained within the range of normal value at 3 days after injury. The BT was higher than the RT in the patients in acute phase of severe head injury, and the difference between the BT and the RT significantly increased after treatment of mild hypothermia. Hyperventilation (the partial pressure of carbon dioxide in artery (PaCO2)≈25 mm Hg) decreased the high intracranial pressure (ICP) and significantly decreased the PbtO2.   Conclusions: This study demonstrates that PptO2 and BT monitoring is a safe, reliable and sensitive diagnostic method to follow cerebral oxygenation. It might become an important tool in our treatment regime for patients in the acute phase of severe head injury requiring hypothermia and hyperventilation.

  20. Effects of Hyperoxia on Brain Tissue Oxygen Tension in Non-Sedated, Non- Anesthetized Arctic Ground Squirrels: An Animal Model of Hyperoxic Stress

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    Y. Ma

    2011-01-01

    Full Text Available Arctic Ground Squirrels (AGS are classic hibernators known for their tolerance to hypoxia. AGS have been studied as a model of hypoxia with potential as a medical research model. Problem statement: Their unique resistance to the stressors of low oxygen led us to hypothesize that AGS might also be adaptable to hyperoxia. Approach: This study examined the physiological pattern associated with hyperoxia in response to brain tissue oxygen partial pressure (PtO2, brain temperature (Tbrain, global oxygen consumption (VO2 and respiratory frequency (fR using non-sedated and nonanesthetized Arctic Ground Squirrels (AGS and rats. Results: We found that 1 100% inspired oxygen (FiO2 increased the baseline values of brain PtO2 significantly in both summer euthermic AGS (24.4 ± 3.6-87.3 ± 3.6 mmHg, n=6 and in rats (18.2 ± 5.2-73.3 ± 5.2 mmHg, n = 3; PtO2 was significantly higher in AGS than in rats during hyperoxic exposure; 2 hyperoxic exposure had no effect on brain temperature in either AGS or rats, with the brain temperatures maintaining constancy before, during and after 100% O2 exposure; 3 systemic metabolic rates increased significantly during hyperoxic exposure in both euthermic AGS and rats; moreover, VO2 were significantly lower in AGS than in rats during hyperoxic exposure; 4 the respiratory rates for rats were maintained before, during and after 100% O2 exposure, while the respiratory responding patterns to hyperoxic exposure changed after exposure in AGS. AGS fR was significantly lower after hyperoxic exposure than before the exposure. Conclusion: These results suggest that hyperoxic ventilation induced PtO2 and VO2 differences between AGS and rats and led to altered respiratory patterns between these species. AGS and the rat serves as an excellent comparative model for hypoxic and hyperoxic stress studies of the brain.

  1. Spectromicroscopy of Brain Tissue

    Science.gov (United States)

    Frazer, Bradley; Cannara, Rachel; Gilbert, Benjamin; Destasio, Gelsomina; Ogg, Mandy; Gough, Kathy

    2001-03-01

    X-ray PhotoElectron Emission Microscopy (X-PEEM) was originally developed for studying the surface microchemistry of materials science specimens. It has then evolved into a valuable tool to investigate the magnetic properties of materials and the microchemistry of cells and tissues. We used the MEPHISTO X-PEEM instrument, installed at the UW-Synchrotron Radiation Center to detect trace concentrations of non-physiological elements in senile brain tissue specimens. These tissues contain a large number of plaques, in which all the compounds and elements that the brain does not need are disposed and stored. We hypothesized that plaques should contain elements, such as Si, B, and Al which are very abundant on the Earth crust but absent from healthy tissues. We verified this hypothesis with MEPHISTO and found evidence of Si and B, and suspect Al. We also found a higher than normal concentration of Fe.

  2. Oxygen Regulates Tissue Nitrite Metabolism

    OpenAIRE

    Curtis, Erin; Hsu, Lewis L.; Noguchi, Audrey C.; Geary, Lisa; Shiva, Sruti

    2012-01-01

    Aims: Once dismissed as an inert byproduct of nitric oxide (NO) auto-oxidation, nitrite (NO2-) is now accepted as an endocrine reservoir of NO that elicits biological responses in major organs. While it is known that tissue nitrite is derived from NO oxidation and the diet, little is known about how nitrite is metabolized by tissue, particularly at intermediate oxygen tensions. We investigated the rates and mechanisms of tissue nitrite metabolism over a range of oxygen concentrations. Results...

  3. Brain Oxygenation Monitoring.

    Science.gov (United States)

    Kirkman, Matthew A; Smith, Martin

    2016-09-01

    A mismatch between cerebral oxygen supply and demand can lead to cerebral hypoxia/ischemia and deleterious outcomes. Cerebral oxygenation monitoring is an important aspect of multimodality neuromonitoring. It is increasingly deployed whenever intracranial pressure monitoring is indicated. Although there is a large body of evidence demonstrating an association between cerebral hypoxia/ischemia and poor outcomes, it remains to be determined whether restoring cerebral oxygenation leads to improved outcomes. Randomized prospective studies are required to address uncertainties about cerebral oxygenation monitoring and management. This article describes the different methods of monitoring cerebral oxygenation, their indications, evidence base, limitations, and future perspectives. PMID:27521197

  4. Uncovering effects of ex vivo protease activity during proteomics and peptidomics sample extraction in rat brain tissue by oxygen-18 labeling.

    Science.gov (United States)

    Stingl, Christoph; Söderquist, Marcus; Karlsson, Oskar; Borén, Mats; Luider, Theo M

    2014-06-01

    In biological samples, proteins and peptides are altered by proteolytic activity. The actual ex vivo form of the peptidome or proteome analyzed, therefore, does not always reflect the natural in vivo state. Sample stabilization and sample treatment are thereby decisive for how far these two states diverge. To assess ex vivo formation of peptides, we used enzymatic incorporation of oxygen-18 water during proteolysis (PALeO approach) to label ex-vivo-formed peptides in rodent brain tissue. Rates of ex-vivo-formed peptides were determined in 25 samples that were stabilized and treated by six different protocols, whereby samples were subjected to different conditions such as temperature, urea concentration, and duration of treatment. Samples were measured by nano LC-Orbitrap-MS, and incorporation of oxygen-18 was determined by MS/MS database search and analysis of the precursor isotope pattern. Extent of ex vivo degradations was affected relevantly by the sample treatment protocol applied and stopped almost completely by heat stabilization. Determination of the formation state by oxygen-18 incorporation by MS/MS database search correlated well to more elaborate analysis of the MS isotope pattern. Overall, oxygen-18 labeling in combination with shotgun data-acquisition and MS/MS database search offers an adjuvant and easily applicable tool to monitor sample quality and fidelity in peptide and neuropeptide sample preparations. PMID:24738752

  5. Probing brain oxygenation with near infrared spectroscopy

    CERN Document Server

    Gersten, Alexander; Raz, Amir; Fried, Robert

    2011-01-01

    The fundamentals of near infrared spectroscopy (NIRS) are reviewed. This technique allows to measure the oxygenation of the brain tissue. The particular problems involved in detecting regional brain oxygenation (rSO2) are discussed. The dominant chromophore (light absorber) in tissue is water. Only in the NIR light region of 650-1000 nm, the overall absorption is sufficiently low, and the NIR light can be detected across a thick layer of tissues, among them the skin, the scull and the brain. In this region, there are many absorbing light chromophores, but only three are important as far as the oxygenation is concerned. They are the hemoglobin (HbO2), the deoxy-hemoglobin (Hb) and cytochrome oxidase (CtOx). In the last 20 years there was an enormous growth in the instrumentation and applications of NIRS. . The devices that were used in our experiments were : Somanetics's INVOS Brain Oximeter (IBO) and Toomim's HEG spectrophotometer. The performances of both devices were compared including their merits and draw...

  6. Measurement of brain oxygenation changes using dynamic T1-weighted imaging

    DEFF Research Database (Denmark)

    Haddock, Bryan; Larsson, Henrik B W; Hansen, Adam E;

    2013-01-01

    Magnetic resonance imaging (MRI) has proven useful in evaluating oxygenation in several types of tissue and blood. This study evaluates brain tissue oxygenation changes between normoxia and hyperoxia in healthy subjects using dynamic T1 and T2*-weighted imaging sequences. The change in FiO2 induced...... in the brain with a potential to provide quantitative information on tissue oxygenation....

  7. Malignant brain tumor treatments and hyperbaric oxygenation

    Energy Technology Data Exchange (ETDEWEB)

    Kohshi, Kiyotaka [Univ. of Occupational and Environmental Health, Kitakyushu, Fukuoka (Japan)

    2000-09-01

    Malignant brain tumor treatment and hyperbaric oxygenation: Combined hyperbaric oxygenation (HBO) therapy and radiation therapy of malignant gliomas is reviewed. Malignant glioma tissue is hypoxic, and the efficacy of radiation therapy is increased by raising the oxygen density in glioma tissue. Residual tumor was reduced by a radiation dose of approximately 40 Gy in many cases when radiation therapy was begun within 15 minutes after HBO. In the experiment in animal models with different hypoxic fractions (HFs) of cells (SCCVII and 9L gliosarcoma), the tumor reduction effect was more significant in the SCCVII model, which has a higher HF. When the SCCVII model was irradiated within 30 minutes after HBO, the improvement effect was more significant (1.60-1.78 times) than by irradiation alone. HBO was effective in the treatment of radionecrosis of the brain. However, there were some cases in which radionecrosis progressed when the HBO treatments were discontinued, and the optimal duration of HBO treatment should be determined. It is difficult to differentiate between radionecrosis and tumor recurrence after radiosurgery of a malignant intracranial tumor. When no lesion reduction is observed in response to HBO treatment and steroid administration for about one month, the lesion is concluded to be a recurrence of the tumor, and additional irradiation should be performed. HBO treatment in combination with chemotherapy is also discussed. (K.H.)

  8. Microcirculatory dysfunction and tissue oxygenation in critical illness.

    Science.gov (United States)

    Østergaard, L; Granfeldt, A; Secher, N; Tietze, A; Iversen, N K; Jensen, M S; Andersen, K K; Nagenthiraja, K; Gutiérrez-Lizardi, P; Mouridsen, K; Jespersen, S N; Tønnesen, E K

    2015-11-01

    Severe sepsis is defined by organ failure, often of the kidneys, heart, and brain. It has been proposed that inadequate delivery of oxygen, or insufficient extraction of oxygen in tissue, may explain organ failure. Despite adequate maintenance of systemic oxygen delivery in septic patients, their morbidity and mortality remain high. The assumption that tissue oxygenation can be preserved by maintaining its blood supply follows from physiological models that only apply to tissue with uniformly perfused capillaries. In sepsis, the microcirculation is profoundly disturbed, and the blood supply of individual organs may therefore no longer reflect their access to oxygen. We review how capillary flow patterns affect oxygen extraction efficacy in tissue, and how the regulation of tissue blood flow must be adjusted to meet the metabolic needs of the tissue as capillary flows become disturbed as observed in critical illness. Using the brain, heart, and kidney as examples, we discuss whether disturbed capillary flow patterns might explain the apparent mismatch between organ blood flow and organ function in sepsis. Finally, we discuss diagnostic means of detecting capillary flow disturbance in animal models and in critically ill patients, and address therapeutic strategies that might improve tissue oxygenation by modifying capillary flow patterns. PMID:26149711

  9. Measuring tissue oxygen saturation using NIR spectroscopy

    Science.gov (United States)

    Sircan-Kucuksayan, Aslinur; Uyuklu, Mehmet; Canpolat, Murat

    2014-05-01

    Tissue oxygen saturation (StO2) is known quite useful parameter for medical applications. A spectroscopic method has been developed to diagnose pathologic tissues due to lack of normal blood circulation by measuring tissue oxygen saturation. In the study, human blood samples with different level of oxygen saturations have been prepared and spectra were taken using an optical fiber probe to investigate correlation between the oxygen saturations and the spectra. The experimental set up for the spectroscopic measurements was consists of a miniature NIR light spectrometer, an optical fiber probe, a halogen-tungsten light source and a laptop. A linear correlation between the oxygen saturation of the blood samples and the ratio of the light of wavelengths 660 nm to 790 nm has been found from the spectra. Then, oxygen saturations of the blood samples were estimated from the spectroscopic measurements within an error of 2.9%. Furthermore, it has been shown that the linear dependence between the ratio and the oxygen saturation of the blood samples was valid for the blood samples with different hematocrits. Tissue oxygen saturation has been estimated from the spectroscopic measurements were taken from the fingers of healthy volunteers using the correlation between the spectra and blood oxygen saturation. The tissue StO2 measured was 80% as expected. The technique developed to measure tissue oxygen saturation has potential to diagnose premalignant tissues, follow up prognosis of cancerous tissues, and evaluation of ischemia reperfusion tissues.

  10. Oxygen Delivering Biomaterials for Tissue Engineering

    Science.gov (United States)

    Farris, Ashley L.; Rindone, Alexandra N.; Grayson, Warren L.

    2016-01-01

    Tissue engineering (TE) has provided promising strategies for regenerating tissue defects, but few TE approaches have been translated for clinical applications. One major barrier in TE is providing adequate oxygen supply to implanted tissue scaffolds, since oxygen diffusion from surrounding vasculature in vivo is limited to the periphery of the scaffolds. Moreover, oxygen is also an important signaling molecule for controlling stem cell differentiation within TE scaffolds. Various technologies have been developed to increase oxygen delivery in vivo and enhance the effectiveness of TE strategies. Such technologies include hyperbaric oxygen therapy, perfluorocarbon- and hemoglobin-based oxygen carriers, and oxygen-generating, peroxide-based materials. Here, we provide an overview of the underlying mechanisms and how these technologies have been utilized for in vivo TE applications. Emerging technologies and future prospects for oxygen delivery in TE are also discussed to evaluate the progress of this field towards clinical translation.

  11. Brain Maturity and Variation of Oxygen Extraction in Premature Infants.

    Science.gov (United States)

    El-Dib, Mohamed; Aly, Safwat; Govindan, Rathinaswamy; Mohamed, Mohamed; du Plessis, Adre; Aly, Hany

    2016-07-01

    Objectives The ability of the premature brain to extract and use oxygen has not been studied adequately. This study aimed to determine factors that influence fractional tissue oxygen extraction (FTOE) of the brain in premature infants using near-infrared spectroscopy (NIRS) and pulse oximetry. Study Design We prospectively studied FTOE in very low birth weight (BW) infants (periventricular leukomalacia. Both FTOE short- and long-scale variabilities correlated negatively with GA and positively with postnatal age (PNA). Moreover, FTOE long-scale variability was significantly reduced in infants supported with invasive ventilation. Conclusions In premature infants, cerebral oxygen extraction increased with reduced Hb and severe brain injury. Variability in oxygen extraction showed differential changes with GA and PNAs and was affected by invasive ventilation. PMID:26906179

  12. Oxygen distributions within tissue by phosphorescence quenching

    Science.gov (United States)

    Wilson, David F.; Grosul, Pavel; Rozhkov, Vladimir; Dugan, Benjamin W.; Reitveld, Ivo; Vinogradov, Sergei A.

    2002-06-01

    Oxygen dependent quenching of phosphorescence is a powerful method for measuring oxygen. Phosphors are now available that absorb and emit in the near IR region of the spectrum, are nontoxic, and remain in the blood, allowing rapid measure of oxygen through out selected tissue volumes. In vivo measurements are non-invasive except for the need to inject phosphor into the blood, and phosphorescence lifetimes can be measured without interference by tissue pigments that absorb or fluorescence at the measurement wavelengths. Phosphorescence quenching is uniquely useful for: (1) imaging oxygen in optically clear media or in the surface layer of the tissue, such as in the retina of the eye; (2) determining the distribution of oxygen in media, such as tissue, which have heterogeneous distributions by deconvoluting phosphorescence decay dat. These can be used to calculate the corresponding oxygen histograms. Measurement in 2D grids can b used to construct contour maps of the fraction of the sampled tissue volume with any selected range of oxygen pressures. These maps accurately show the location and size of any regions of hypoxia within the sampled tissue.

  13. Lactate, Glucose and Oxygen Uptake in Human Brain During Recovery from Maximal Exercise

    DEFF Research Database (Denmark)

    Kojiro, I.; Schmalbruch, I.K.; Quistorff, B.;

    1999-01-01

    Skeletal muscle, brain lactate uptake, brain oxygen uptake, energy metabolism, brain glucose uptake......Skeletal muscle, brain lactate uptake, brain oxygen uptake, energy metabolism, brain glucose uptake...

  14. Metabolomic Analyses of Brain Tissue in Sepsis Induced by Cecal Ligation Reveal Specific Redox Alterations--Protective Effects of the Oxygen Radical Scavenger Edaravone.

    Science.gov (United States)

    Hara, Naomi; Chijiiwa, Miyuki; Yara, Miki; Ishida, Yusuke; Ogiwara, Yukihiko; Inazu, Masato; Kuroda, Masahiko; Karlsson, Michael; Sjovall, Fredrik; Elmér, Eskil; Uchino, Hiroyuki

    2015-12-01

    The pathophysiology of sepsis-associated encephalopathy (SAE) is complex and remains incompletely elucidated. Dysregulated reactive oxygen species (ROS) production and mitochondrial-mediated necrotic-apoptotic pathway have been proposed as part of the pathogenesis. The present study aimed at analyzing the preventive effect of the free radical scavenger edaravone on sepsis-induced brain alterations. Sepsis was induced by cecal ligation and puncture (CLP) and the mice were divided into three groups-CLP vehicle (CLPV), CLP and edaravone (MCI-186, 3-methyl-1-phenyl-2-pyrazolin-5-one) (CLPE), and sham-operated (Sham). Mice in CLPV and CLPE were injected with saline or edaravone intraperitoneally at a dose of 10 mg/kg twice daily. The treatments were initiated 4 days prior to the surgical procedure. Mortality, histological changes, electron microscopy (EM), and expression of Bcl-2 family genes (Bcl-2 and Bax) were analyzed in selected brain regions. CLPE showed significant improvement in survival compared with CLPV 18 h postinduction of sepsis (P free radical scavenger edavarone reduces mortality of septic mice and protects against sepsis-induced neuronal cell death.

  15. Oxygen diffusion and oxygen effect in tumor tissue

    International Nuclear Information System (INIS)

    The diffusion of oxygen in tumor cords of bronchus carcinoma of the lung have been studied with refined computer methods for solving the diffusion equation in axis symmetric tumor structures. In this tumor configuration we may find three different regions consisting of euoxic cells, hypoxic tumor cells and necrotic parts. In the case of oxygen supply from a capillary inside a cylinder of tumor tissue with radius 200 μm or in a tumor cord of radius 300 μm with oxygen supply by capillaries outside, we get a relation of well oxygenated cells to hypoxic cells approximately as 1:8 or as 1:1.1 respectively. Of course most of the tumor cords observed in histological slices have smaller diameters, so that an average of approximately 20% hypoxic cells can be assumed. Based on the work of Ardenne, the diffusion of oxygen and glucose in a tumor of type DS-carcinosarcom has been investigated in both intact tumor and tumor treated with ionizing radiation. We can show that a strong reoxygenation effect takes place in that the well supplied regions may increase in some tumor configurations up to a factor of four by volume. The biological consequences of the oxygen pressure determined in tumor cells are discussed in detail. The investigation of oxygen diffusion in the intercapillary tumor region should give a quantitative physical basis for considering the oxygen effect with the aim to explain the advantages of neutron therapy against conventional radiotherapy. (orig./MG)

  16. Improvement of oxygen supply by an artificial carrier in combination with normobaric oxygenation decreases the volume of tissue hypoxia and tissue damage from transient focal cerebral ischemia

    NARCIS (Netherlands)

    Seiffge, David J.; Lapina, Natalia E.; Tsagogiorgas, Charalambos; Theisinger, Bastian; Henning, Robert H.; Schilling, Lothar

    2012-01-01

    Tissue hypoxia may play an important role in the development of ischemic brain damage. In the present study we investigated in a rat model of transient focal brain ischemia the neuroprotective effects of increasing the blood oxygen transport capacity by applying a semifluorinated alkane (SFA)-contai

  17. Metabolic Prosthesis for Oxygenation of Ischemic Tissue

    Energy Technology Data Exchange (ETDEWEB)

    Greenbaum, Elias [ORNL

    2009-01-01

    This communication discloses new ideas and preliminary results on the development of a "metabolic prosthesis" for local oxygenation of ischemic tissue under physiological neutral conditions. We report for the first time the selective electrolysis of physiological saline by repetitively pulsed charge-limited electrolysis for the production of oxygen and suppression of free chlorine. For example, using 800 A amplitude current pulses and <200 sec pulse durations, we demonstrated prompt oxygen production and delayed chlorine production at the surface of a shiny 0.85 mm diameter spherical platinum electrode. The data, interpreted in terms of the ionic structure of the electric double layer, suggest a strategy for in situ production of metabolic oxygen via a new class of "smart" prosthetic implants for dealing with ischemic disease such as diabetic retinopathy. We also present data indicating that drift of the local pH of the oxygenated environment can be held constant using a feedback-controlled three electrode electrolysis system that chooses anode and cathode pair based on pH data provided by local microsensors. The work is discussed in the context of diabetic retinopathy since surgical techniques for multielectrode prosthetic implants aimed at retinal degenerative diseases have been developed.

  18. Metabolomic Analyses of Brain Tissue in Sepsis Induced by Cecal Ligation Reveal Specific Redox Alterations-Protective Effects of the Oxygen Radical Scavenger Edaravone

    DEFF Research Database (Denmark)

    Hara, Naomi; Chijiiwa, Miyuki; Yara, Miki;

    2015-01-01

    at analyzing the preventive effect of the free radical scavenger edaravone on sepsis-induced brain alterations. Sepsis was induced by cecal ligation and puncture (CLP) and the mice were divided into three groups-CLP vehicle (CLPV), CLP and edaravone (MCI-186, 3-methyl-1-phenyl-2-pyrazolin-5-one) (CLPE...... (Bcl-2 and Bax) were analyzed in selected brain regions. CLPE showed significant improvement in survival compared with CLPV 18 h postinduction of sepsis (P ... induced by cecal ligation alters cerebral redox status and supports a proapoptotic phenotype. The free radical scavenger edavarone reduces mortality of septic mice and protects against sepsis-induced neuronal cell death....

  19. Signals Analysis and Clinical Validation of Blood and Oxygen Data in Human Brain

    Institute of Scientific and Technical Information of China (English)

    LI Kai-yang; LIU Li-jun; WANG Xiang; QIN Zhao; XIE Ze-ping

    2005-01-01

    With a self-made near-infrared analytical instrument to blood and oxygen parameters in human brain, 80 cases in which 20 are healthy persons and 30are anaesthetised cases and others are patients with heart function lack is taken to examine, and the data of blood and oxygen in brain tissue were collected and analyzed by the method of power spectrum and correlation function. The results indicate that: (1) The average brain oxygen saturation of healthy persons and anaesthetised cases is about 80%, in accord with normal parameter of physiology. Contrastively, the average brain oxygen saturation of patients with heart function lack is 72. 8%, which is obviously less than that of healthy persons and anaesthetised cases. The probability of medical statistics is less than 0. 01. (2) The shapes of wave of brain blood and oxygen for the healthy person and the anaesthetised case reveal small periodical fluctuations with stable shape and base line, and the trend of increase or decrease of blood and oxygen parameters in brain tissue is synchronous and a phase reversal, but for the patient with heart function lack in a brain oxygen lack state, the shapes of wave are irregular. This is a hint that near infrared light passing through tissue can reflect the intuitionistic change of brain blood and oxygen parameters. (3) The power spectra of brain blood and oxygen for the healthy person and the anaesthetised case has a clear main peak, narrow bandwidth and perfect superposition each other, but the power spectra for the patient with heart function lack in a brain oxygen lack state is on the contrary. (4) The average cross correlation coefficient of brain blood and oxygen for healthy persons and anaesthetised cases is -0. 9825±0. 1027 close to -1. But the average cross correlation coefficient for patients with heart function lack in a brain oxygen lack state is merely -0. 8923± 0. 1035 which is obviously greater than -1 and the probability of medical statistics is less than 0. 01

  20. Temperature Effects on Brain Tissue in Compression

    CERN Document Server

    Rashid, Badar; Gilchrist, Michael; 10.1016/j.jmbbm.2012.04.005

    2013-01-01

    Extensive research has been carried out for at least 50 years to understand the mechanical properties of brain tissue in order to understand the mechanisms of traumatic brain injury (TBI). The observed large variability in experimental results may be due to the inhomogeneous nature of brain tissue and to the broad range of test conditions. However, test temperature is also considered as one of the factors influencing the properties of brain tissue. In this research, the mechanical properties of porcine brain have been investigated at 22C (room temperature) and at 37C (body temperature) while maintaining a constant preservation temperature of approximately 4-5C. Unconfined compression tests were performed at dynamic strain rates of 30 and 50/s using a custom made test apparatus. There was no significant difference (p = 0.8559 - 0.9290) between the average engineering stresses of the brain tissue at the two different temperature conditions. The results of this study should help to understand the behavior of bra...

  1. Ischemia/reperfusion mediated oxygen free radical production in rat brain endothelium

    Energy Technology Data Exchange (ETDEWEB)

    Grammas, P.; Wood, K. (Univ. of Oklahoma, Oklahoma City (United States)); Liu, G.J.; Floyd, R.A. (Oklahoma Medical Research Foundation, Oklahoma City (United States)); Wood, K. (Univ. of Oklahoma Health Sciences Center, Oklahoma City (United States) Oklahoma Medical Research Foundation, Oklahoma City (United States))

    1991-03-11

    Oxygen free radicals have been increasingly implicated in ischemia/reperfusion mediated injury to tissue. Recent methods of assessing tissue oxygen free radical flux including spin trapping, salicylate hydroxylation, protein oxidation and specific enzymatic activity loss have clearly shown that ischemia/reperfusion mediates oxidative damage in brain. Vascular endothelia cells are increasingly implicated in inactivating oxidative damage. The authors have used salicylate to assess hydroxyl free radical flux during an anoxia-reoxygenation insult in isolated brain microvessels. Brain microvessels that were subjected to a 20 min anoxia period and then reoxygenated for 20 min hydroxylated salicylate to form tissue localized 2,3-dihydroxybenzoic acid (2,3-DHBA) whereas microvessels that remained oxygenated throughout contained very little 2,3-DHBA. The data suggest that anoxia/reoxygenation of microvessels produces tissue localized hydroxyl free radical flux.

  2. Modelling Brain Tissue using Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Dyrby, Tim Bjørn

    2008-01-01

    Diffusion MRI, or diffusion weighted imaging (DWI), is a technique that measures the restricted diffusion of water molecules within brain tissue. Different reconstruction methods quantify water-diffusion anisotropy in the intra- and extra-cellular spaces of the neural environment. Fibre tracking...... be used. Within a two year period, no statistical inter- or intra-brain difference in the diffusion coefficient was found in perfusion fixated minipig brains. However, a decreasing tendency in the diffusion coefficient was found at the last time points about 24 months post mortem and might be explained...... experiment. This includes the selection of independent anatomical data to be used to derive a gold standard, the selection of a gyrated animal model in place of the human brain, objective selection of the seed region to initiate, and a waypoint region to constrain the tractography results....

  3. Modelling Brain Tissue using Magnetic Resonance Imaging

    OpenAIRE

    Dyrby, Tim Bjørn; Hansen, Lars Kai

    2008-01-01

    Diffusion MRI, or diffusion weighted imaging (DWI), is a technique that measures the restricted diffusion of water molecules within brain tissue. Different reconstruction methods quantify water-diffusion anisotropy in the intra- and extra-cellular spaces of the neural environment. Fibre tracking models then use the directions of greatest diffusion as estimates of white matter fibre orientation. Several fibre tracking algorithms have emerged in the last few years that provide reproducible visu...

  4. Hyperbaric oxygen therapy improves cognitive functioning after brain injury

    Institute of Scientific and Technical Information of China (English)

    Su Liu; Guangyu Shen; Shukun Deng; Xiubin Wang; Qinfeng Wu; Aisong Guo

    2013-01-01

    Hyperbaric oxygen therapy has been widely applied and recognized in the treatment of brain injury;however, the correlation between the protective effect of hyperbaric oxygen therapy and changes of metabolites in the brain remains unclear. To investigate the effect and potential mechanism of hyperbaric oxygen therapy on cognitive functioning in rats, we established traumatic brain injury models using Feeney’s free fal ing method. We treated rat models with hyperbaric oxygen therapy at 0.2 MPa for 60 minutes per day. The Morris water maze test for spatial navigation showed that the average escape latency was significantly prolonged and cognitive function decreased in rats with brain injury. After treatment with hyperbaric oxygen therapy for 1 and 2 weeks, the rats’ spatial learning and memory abilities were improved. Hydrogen proton magnetic resonance spectroscopy analysis showed that the N-acetylaspartate/creatine ratio in the hippocampal CA3 region was sig-nificantly increased at 1 week, and the N-acetylaspartate/choline ratio was significantly increased at 2 weeks after hyperbaric oxygen therapy. Nissl staining and immunohistochemical staining showed that the number of nerve cells and Nissl bodies in the hippocampal CA3 region was significantly increased, and glial fibril ary acidic protein positive cells were decreased after a 2-week hyperbaric oxygen therapy treatment. Our findings indicate that hyperbaric oxygen therapy significantly im-proves cognitive functioning in rats with traumatic brain injury, and the potential mechanism is me-diated by metabolic changes and nerve cellrestoration in the hippocampal CA3 region.

  5. Measuring microvascular and mitochondrial oxygen tension: novel techniques for studying tissue oxygenation

    NARCIS (Netherlands)

    E.G. Mik

    2011-01-01

    This thesis describes the implementation of novel approaches for measuring tissue oxygenation based on oxygen-dependent quenching of the triplet-state lifetime of porphyrins. Ultimately we created a tool for assessment of mitochondrial oxygen tension in vivo. The first measurements indicate much hig

  6. Myoglobin Expression in Chelonia mydas Brain, Heart and Liver Tissues

    Directory of Open Access Journals (Sweden)

    RINI PUSPITANINGRUM

    2010-09-01

    Full Text Available An understanding of the underpinning physiology and biochemistry of animals is essential to properly understand the impact of anthropogenic changes and natural catastrophes upon the conservation of endangered species. An observation on the tissue location of the key respiratory protein, myoglobin, now opens up new opportunities for understanding how hypoxia tolerance impacts on diving lifestyle in turtles. The respiratory protein, myoglobin has functions other than oxygen binding which are involved in hypoxia tolerance, including metabolism of reactive oxygen species and of the vascular function by metabolism of nitric oxide. Our work aims to determine whether myoglobin expression in the green turtle exists in multiple non muscle tissues and to confirm the hypothesis that reptiles also have a distributed myoglobin expression which is linked to the hypoxiatolerant trait. This initial work in turtle hatch Chelonia mydas confirms the presence of myoglobin transcriptin brain, heart and liver tissues. Furthermore, it will serve as a tool for completing the sequence and generating an in situ hybridization probe for verifying of cell location in expressing tissues.

  7. Low oxygen concentrations impair tissue development in tissue-engineered cardiovascular constructs

    NARCIS (Netherlands)

    Vlimmeren, M.A.A. van; Driessen-Mol, A.; Oomens, C.W.J.; Broek, M. van den; Stoop, R.; Bouten, C.V.C.; Baaijens, F.P.T.

    2012-01-01

    Cardiovascular tissue engineering has shown considerable progress, but in vitro tissue conditioning to stimulate the development of a functional extracellular matrix still needs improvement. We investigated the environmental factor oxygen concentration for its potential to increase the amount of col

  8. Tissue tracking: applications for brain MRI classification

    Science.gov (United States)

    Melonakos, John; Gao, Yi; Tannenbaum, Allen

    2007-03-01

    Bayesian classification methods have been extensively used in a variety of image processing applications, including medical image analysis. The basic procedure is to combine data-driven knowledge in the likelihood terms with clinical knowledge in the prior terms to classify an image into a pre-determined number of classes. In many applications, it is difficult to construct meaningful priors and, hence, homogeneous priors are assumed. In this paper, we show how expectation-maximization weights and neighboring posterior probabilities may be combined to make intuitive use of the Bayesian priors. Drawing upon insights from computer vision tracking algorithms, we cast the problem in a tissue tracking framework. We show results of our algorithm on the classification of gray and white matter along with surrounding cerebral spinal fluid in brain MRI scans. We show results of our algorithm on 20 brain MRI datasets along with validation against expert manual segmentations.

  9. Brain Abscess After Soft Tissue Infection

    Directory of Open Access Journals (Sweden)

    Akoz A et al.

    2013-06-01

    Full Text Available The brain abscess, which is a focal intracerebral infection, is one of the serious complications of the head infections. It generally occurs in the immunocompromised patients due to the spreading from another infection focus on the body. It can be seen with the findings such as fever, headache, nausea, vomiting, diplopia, dysarthria and paralysis. Imaging methods are used in the diagnosis. In its treatment, antibiotherapy and surgical methods can be used. Sometimes, as in our case, brain abscess can appear in a case which is thought to be a simple soft tissue infection. We think that especially, at the diagnosis and treatment stage of infections in head and neck region, physicians must be more careful and diligent.

  10. [Utility of hyperbaric oxygenation in radiotherapy for malignant brain tumors--a literature review].

    Science.gov (United States)

    Beppu, Takaaki; Tanaka, Katsuyuki; Kohshi, Kiyotaka

    2009-06-01

    Over the past 50 years, hyperbaric oxygenation (HBO) therapy has been used in a wide variety of medical conditions; this theraphy causes an increase in oxygen tension in blood and tissues. In the treatment of malignant gliomas, HBO therapy is used for the radiosensitization of cells in combination with radiotherapy (RT). Further, HBO therapy is applied for the treatment and prevention of radiation-induced brain necrosis that is the most serious complication observed after radiosurgery. We reviewed the literature to evaluate the manner in which HBO therapy contributes to clinical fields in cases of RT administration for malignant brain tumors.

  11. Renal Tissue Oxygenation in Essential Hypertension and Chronic Kidney Disease

    OpenAIRE

    Menno Pruijm; Lucie Hofmann; Bruno Vogt; Marie-Eve Muller; Maciej Piskunowicz; Matthias Stuber; Michel Burnier

    2013-01-01

    Animal studies suggest that renal tissue hypoxia plays an important role in the development of renal damage in hypertension and renal diseases, yet human data were scarce due to the lack of noninvasive methods. Over the last decade, blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI), detecting deoxyhemoglobin in hypoxic renal tissue, has become a powerful tool to assess kidney oxygenation noninvasively in humans. This paper provides an overview of BOLD-MRI studies perform...

  12. Intraoperative transfusion threshold and tissue oxygenation

    DEFF Research Database (Denmark)

    Nielsen, K; Dahl, B; Johansson, P I;

    2012-01-01

    Transfusion with allogeneic red blood cells (RBCs) may be needed to maintain oxygen delivery during major surgery, but the appropriate haemoglobin (Hb) concentration threshold has not been well established. We hypothesised that a higher level of Hb would be associated with improved subcutaneous...

  13. High-spatial-resolution mapping of the oxygen concentration in cortical tissue (Conference Presentation)

    Science.gov (United States)

    Jaswal, Rajeshwer S.; Yaseen, Mohammad A.; Fu, Buyin; Boas, David A.; Sakadžic, Sava

    2016-03-01

    Due to a lack of imaging tools for high-resolution imaging of cortical tissue oxygenation, the detailed maps of the oxygen partial pressure (PO2) around arterioles, venules, and capillaries remain largely unknown. Therefore, we have limited knowledge about the mechanisms that secure sufficient oxygen delivery in microvascular domains during brain activation, and provide some metabolic reserve capacity in diseases that affect either microvascular networks or the regulation of cerebral blood flow (CBF). To address this challenge, we applied a Two-Photon PO2 Microscopy to map PO2 at different depths in mice cortices. Measurements were performed through the cranial window in the anesthetized healthy mice as well as in the mouse models of microvascular dysfunctions. In addition, microvascular morphology was recorded by the two-photon microscopy at the end of each experiment and subsequently segmented. Co-registration of the PO2 measurements and exact microvascular morphology enabled quantification of the tissue PO2 dependence on distance from the arterioles, capillaries, and venules at various depths. Our measurements reveal significant spatial heterogeneity of the cortical tissue PO2 distribution that is dominated by the high oxygenation in periarteriolar spaces. In cases of impaired oxygen delivery due to microvascular dysfunction, significant reduction in tissue oxygenation away from the arterioles was observed. These tissue domains may be the initial sites of cortical injury that can further exacerbate the progression of the disease.

  14. Development of 200-channel mapping system for tissue oxygenation measured by near-infrared spectroscopy

    Science.gov (United States)

    Niwayama, Masatsugu; Kohata, Daisuke; Shao, Jun; Kudo, Nobuki; Hamaoka, Takatumi; Katsumura, Toshihito; Yamamoto, Katsuyuki

    2000-07-01

    Near-infrared spectroscopy (NIRS) is a very useful technique for noninvasive measurement of tissue oxygenation. Among various methods of NIRS, continuous wave near-infrared spectroscopy (CW- NIRS) is especially suitable for real-time measurement and for practical use. CW-NIRS has recently been applied in vivo reflectance imaging of muscle oxygenation and brain activity. However, conventional mapping systems do not have a sufficient mapping area at present. Moreover, they do not enable quantitative measurement of tissue oxygenation because conventional NIRS is based on the inappropriate assumption that tissue is homogeneous. In this study, we developed a 200-channel mapping system that enables measurement of changes in oxygenation and blood volume and that covers a wider area (30 cm x 20 cm) than do conventional systems. The spatial resolution (source- detector separation) of this system is 15 mm. As for the effcts of tissue inhomogeneity on muscle oxygenation measurement, subcutaneous adipose tissue greatly reduces measurement sensitivity. Therefore, we also used a correction method for influence of the subcutaneous fat layer so that we could obtain quantitative changes in concentrations of oxy- and deoxy- hemoglobin. We conducted exercise tests and measured the changed in hemoglobin concentration in the thigh using the new system. The working muscles in the exercises could be imaged, and the heterogeneity of the muscles was shown. These results demonstrated the new 200-channel mapping system enables observation of the distribution of muscle metabolism and localization of muscle function.

  15. Brain magnetic resonance imaging with contrast dependent on blood oxygenation

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, S.; Lee, T.M.; Kay, A.R.; Tank, D.W. (AT and T Bell Laboratories, Murray Hill, NJ (United States))

    1990-12-01

    Paramagnetic deoxyhemoglobin in venous blood is a naturally occurring contrast agent for magnetic resonance imaging (MRI). By accentuating the effects of this agent through the use of gradient-echo techniques in high yields, the authors demonstrate in vivo images of brain microvasculature with image contrast reflecting the blood oxygen level. This blood oxygenation level-dependent (BOLD) contrast follows blood oxygen changes induced by anesthetics, by insulin-induced hypoglycemia, and by inhaled gas mixtures that alter metabolic demand or blood flow. The results suggest that BOLD contrast can be used to provide in vivo real-time maps of blood oxygenation in the brain under normal physiological conditions. BOLD contrast adds an additional feature to magnetic resonance imaging and complement other techniques that are attempting to provide position emission tomography-like measurements related to regional neural activity.

  16. Brain magnetic resonance imaging with contrast dependent on blood oxygenation

    International Nuclear Information System (INIS)

    Paramagnetic deoxyhemoglobin in venous blood is a naturally occurring contrast agent for magnetic resonance imaging (MRI). By accentuating the effects of this agent through the use of gradient-echo techniques in high yields, the authors demonstrate in vivo images of brain microvasculature with image contrast reflecting the blood oxygen level. This blood oxygenation level-dependent (BOLD) contrast follows blood oxygen changes induced by anesthetics, by insulin-induced hypoglycemia, and by inhaled gas mixtures that alter metabolic demand or blood flow. The results suggest that BOLD contrast can be used to provide in vivo real-time maps of blood oxygenation in the brain under normal physiological conditions. BOLD contrast adds an additional feature to magnetic resonance imaging and complement other techniques that are attempting to provide position emission tomography-like measurements related to regional neural activity

  17. Correlation between light scattering signal and tissue reversibility in rat brain exposed to hypoxia

    Science.gov (United States)

    Kawauchi, Satoko; Sato, Shunichi; Uozumi, Yoichi; Nawashiro, Hiroshi; Ishihara, Miya; Kikuchi, Makoto

    2010-02-01

    Light scattering signal is a potential indicator of tissue viability in brain because cellular and subcellular structural integrity should be associated with cell viability in brain tissue. We previously performed multiwavelength diffuse reflectance measurement for a rat global ischemic brain model and observed a unique triphasic change in light scattering at a certain time after oxygen and glucose deprivation. This triphasic scattering change (TSC) was shown to precede cerebral ATP exhaustion, suggesting that loss of brain tissue viability can be predicted by detecting scattering signal. In the present study, we examined correlation between light scattering signal and tissue reversibility in rat brain in vivo. We performed transcranial diffuse reflectance measurement for rat brain; under spontaneous respiration, hypoxia was induced for the rat by nitrogen gas inhalation and reoxygenation was started at various time points. We observed a TSC, which started at 140 +/- 15 s after starting nitrogen gas inhalation (mean +/- SD, n=8). When reoxygenation was started before the TSC, all rats survived (n=7), while no rats survived when reoxygenation was started after the TSC (n=8). When reoxygenation was started during the TSC, rats survived probabilistically (n=31). Disability of motor function was not observed for the survived rats. These results indicate that TSC can be used as an indicator of loss of tissue reversibility in brains, providing useful information on the critical time zone for treatment to rescue the brain.

  18. Renal Tissue Oxygenation in Essential Hypertension and Chronic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Menno Pruijm

    2013-01-01

    Full Text Available Animal studies suggest that renal tissue hypoxia plays an important role in the development of renal damage in hypertension and renal diseases, yet human data were scarce due to the lack of noninvasive methods. Over the last decade, blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI, detecting deoxyhemoglobin in hypoxic renal tissue, has become a powerful tool to assess kidney oxygenation noninvasively in humans. This paper provides an overview of BOLD-MRI studies performed in patients suffering from essential hypertension or chronic kidney disease (CKD. In line with animal studies, acute changes in cortical and medullary oxygenation have been observed after the administration of medication (furosemide, blockers of the renin-angiotensin system or alterations in sodium intake in these patient groups, underlining the important role of renal sodium handling in kidney oxygenation. In contrast, no BOLD-MRI studies have convincingly demonstrated that renal oxygenation is chronically reduced in essential hypertension or in CKD or chronically altered after long-term medication intake. More studies are required to clarify this discrepancy and to further unravel the role of renal oxygenation in the development and progression of essential hypertension and CKD in humans.

  19. Susceptibility weighted imaging of stroke brain in response to normobaric oxygen (NBO) therapy

    Science.gov (United States)

    Zhou, Iris Y.; Igarashi, Takahiro; Guo, Yingkun; Sun, Phillip Z.

    2015-03-01

    The neuroprotective effect of oxygen leads to recent interest in normobaric oxygen (NBO) therapy after acute ischemic stroke. However, the mechanism remains unclear and inconsistent outcomes were reported in human studies. Because NBO aims to improve brain tissue oxygenation by enhancing oxygen delivery to ischemic tissue, monitoring the oxygenation level changes in response to NBO becomes necessary to elucidate the mechanism and to assess the efficacy. Susceptibility weighted imaging (SWI) which provides a new MRI contrast by combining the magnitude and phase images is fit for purpose. SWI is sensitive to deoxyhemoglobin level changes and thus can be used to evaluate the cerebral metabolic rate of oxygen. In this study, SWI was used for in vivo monitoring of oxygenation changes in a rat model of permanent middle cerebral artery occlusion (MCAO) before, during and after 30 min of NBO treatment. Regions of interest in ischemic core, penumbra and contralateral normal area were generated based on diffusionweighted imaging and perfusion imaging. Significant differences in SWI indicating different oxygenation levels were generally found: contralateral normal > penumbra > ischemic core. Ischemic core showed insignificant increase in oxygenation during NBO and returned to pre-treatment level after termination of NBO. Meanwhile, the oxygenation levels slightly increased in contralateral normal and penumbra regions during NBO and significantly decreased to a level lower than pre-treatment after termination of NBO, indicating secondary metabolic disruption upon the termination of transient metabolic support from oxygen. Further investigation of NBO effect combined with reperfusion is necessary while SWI can be used to detect hemorrhagic transformation after reperfusion.

  20. Effects of hyperbaric oxygenation on hemodynamics and oxygen balance in tissues of miners with vibration pathologies

    Energy Technology Data Exchange (ETDEWEB)

    Larin, Eh.N.; Samokhatko, E.V.; Dorogan' , N.A. (Institut Gigieny Truda i Profzabolevanii, Krivoi Rog (Ukraine))

    1992-08-01

    Studies antihypoxic and microcirculation-stimulating effects of hyperbaric oxygenation in patients suffering from vibration pathologies. Combined clinical and laboratory examinations were conducted on a group of 56 miners diagnosed with the first stage of vibration disease. Ages of the patients varied from 40 to 49 years and duration of work at vibratory type tools was over 15 years. Hyperbaric oxygenation therapy was performed for 40-50 minutes every day in an OKA-MT single-seat compression chamber at a pressure of 1.5-1.7 atm. Hyperbaric therapy was accompanied by treatment with vitamins, biogenic stimulators, ganglioplegics and spasmolytics. Detailed observational data are given. The following conclusions are presented: hyperbaric oxygenation produces a positive effect on oxygen balance in tissues and regional bloodstreams and increases physical endurance; further research for elaborating therapeutic conditions of hyperbaric oxygenation for patients suffering from accompanying diseases is justified. 7 refs.

  1. A new antigen retrieval technique for human brain tissue.

    Directory of Open Access Journals (Sweden)

    Raúl Alelú-Paz

    Full Text Available Immunohistochemical staining of tissues is a powerful tool used to delineate the presence or absence of an antigen. During the last 30 years, antigen visualization in human brain tissue has been significantly limited by the masking effect of fixatives. In the present study, we have used a new method for antigen retrieval in formalin-fixed human brain tissue and examined the effectiveness of this protocol to reveal masked antigens in tissues with both short and long formalin fixation times. This new method, which is based on the use of citraconic acid, has not been previously utilized in brain tissue although it has been employed in various other tissues such as tonsil, ovary, skin, lymph node, stomach, breast, colon, lung and thymus. Thus, we reported here a novel method to carry out immunohistochemical studies in free-floating human brain sections. Since fixation of brain tissue specimens in formaldehyde is a commonly method used in brain banks, this new antigen retrieval method could facilitate immunohistochemical studies of brains with prolonged formalin fixation times.

  2. Reduced Cerebral Oxygen Content in the DG and SVZ In Situ Promotes Neurogenesis in the Adult Rat Brain In Vivo.

    Directory of Open Access Journals (Sweden)

    Kuan Zhang

    Full Text Available Neurogenesis in the adult brain occurs mainly within two neurogenic structures, the dentate gyrus (DG of the hippocampus and the sub-ventricular zone (SVZ of the forebrain. It has been reported that mild hypoxia promoted the proliferation of Neural Stem Cells (NSCsin vitro. Our previous study further demonstrated that an external hypoxic environment stimulated neurogenesis in the adult rat brain in vivo. However, it remains unknown how external hypoxic environments affect the oxygen content in the brain and result in neurogenesis. Here we use an optical fiber luminescent oxygen sensor to detect the oxygen content in the adult rat brain in situ under normoxia and hypoxia. We found that the distribution of oxygen in cerebral regions is spatiotemporally heterogeneous. The Po2 values in the ventricles (45∼50 Torr and DG (approximately 10 Torr were much higher than those of other parts of the brain, such as the cortex and thalamus (approximately 2 Torr. Interestingly, our in vivo studies showed that an external hypoxic environment could change the intrinsic oxygen content in brain tissues, notably reducing oxygen levels in both the DG and SVZ, the major sites of adult neurogenesis. Furthermore, the hypoxic environment also increased the expression of HIF-1α and VEGF, two factors that have been reported to regulate neurogenesis, within the DG and SVZ. Thus, we have demonstrated that reducing the oxygen content of the external environment decreased Po2 levels in the DG and SVZ. This reduced oxygen level in the DG and SVZ might be the main mechanism triggering neurogenesis in the adult brain. More importantly, we speculate that varying oxygen levels may be the physiological basis of the regionally restricted neurogenesis in the adult brain.

  3. Brain and muscle oxygenation monitoring using near-infrared spectroscopy (NIRS) during all-night sleep

    Science.gov (United States)

    Zhang, Zhongxing; Khatami, Ramin

    2013-03-01

    The hemodynamic changes during natural human sleep are still not well understood. NIRS is ideally suited for monitoring the hemodynamic changes during sleep due to the properties of local measurement, totally safe application and good tolerance to motion. Several studies have been conducted using NIRS in both normal subjects and patients with various sleep disorders during sleep to characterize the hemodynamic changing patterns during different sleep stages and during different symptoms such as obstructive apneas. Here we assessed brain and muscle oxygenation changes in 7 healthy adults during all-night sleep with combined polysomnography measurement to test the notion if hemodynamic changes in sleep are indeed brain specific. We found that muscle and brain showed similar hemodynamic changes during sleep initiation. A decrease in HbO2 and tissue oxygenation index (TOI) while an increase in HHb was observed immediately after sleep onset, and an opposite trend was found after transition with progression to deeper slow-wave sleep (SWS) stage. Spontaneous low frequency oscillations (LFO) and very low frequency oscillations (VLFO) were smaller (Levene's test, psleep (LS) and rapid-eye-movement (REM) sleep in both brain and muscle. Spectral analysis of the NIRS signals measured from brain and muscle also showed reductions in VLFO and LFO powers during SWS with respect to LS and REM sleep. These results indicate a systemic attenuation rather than local cerebral reduction of spontaneous hemodynamic activity in SWS. A systemic physiological mechanism may exist to regulate the hemodynamic changes in brain and muscle during sleep.

  4. Multichannel optical brain imaging to separate cerebral vascular, tissue metabolic, and neuronal effects of cocaine

    Science.gov (United States)

    Ren, Hugang; Luo, Zhongchi; Yuan, Zhijia; Pan, Yingtian; Du, Congwu

    2012-02-01

    Characterization of cerebral hemodynamic and oxygenation metabolic changes, as well neuronal function is of great importance to study of brain functions and the relevant brain disorders such as drug addiction. Compared with other neuroimaging modalities, optical imaging techniques have the potential for high spatiotemporal resolution and dissection of the changes in cerebral blood flow (CBF), blood volume (CBV), and hemoglobing oxygenation and intracellular Ca ([Ca2+]i), which serves as markers of vascular function, tissue metabolism and neuronal activity, respectively. Recently, we developed a multiwavelength imaging system and integrated it into a surgical microscope. Three LEDs of λ1=530nm, λ2=570nm and λ3=630nm were used for exciting [Ca2+]i fluorescence labeled by Rhod2 (AM) and sensitizing total hemoglobin (i.e., CBV), and deoxygenated-hemoglobin, whereas one LD of λ1=830nm was used for laser speckle imaging to form a CBF mapping of the brain. These light sources were time-sharing for illumination on the brain and synchronized with the exposure of CCD camera for multichannel images of the brain. Our animal studies indicated that this optical approach enabled simultaneous mapping of cocaine-induced changes in CBF, CBV and oxygenated- and deoxygenated hemoglobin as well as [Ca2+]i in the cortical brain. Its high spatiotemporal resolution (30μm, 10Hz) and large field of view (4x5 mm2) are advanced as a neuroimaging tool for brain functional study.

  5. Improving the specificity of R2' to the deoxyhaemoglobin content of brain tissue: Prospective correction of macroscopic magnetic field gradients

    OpenAIRE

    Blockley, NP; Stone, AJ

    2016-01-01

    The reversible transverse relaxation rate, R2', is sensitive to the deoxyhaemoglobin content of brain tissue, enabling information about the oxygen extraction fraction to be obtained. However, R2' is also sensitive to macroscopic magnetic field gradients, particularly at air-tissue interfaces where a large susceptibility difference is present. It is important that this latter effect is minimised in order to produce meaningful estimates of blood oxygenation. Therefore, the aim of this study wa...

  6. Facilitated assessment of tissue loss following traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Anders eHånell

    2012-03-01

    Full Text Available All experimental models of traumatic brain injury (TBI result in a progressive loss of brain tissue. The extent of tissue loss reflects the injury severity and can be measured to evaluate the potential neuroprotective effect of experimental treatments. Quantitation of tissue volumes is commonly performed using evenly spaced brain sections stained using routine histochemical methods and digitally captured. The brain tissue areas are then measured and the corresponding volumes are calculated using the distance between the sections. Measurements of areas are usually performed using a general purpose image analysis software and the results are then transferred to another program for volume calculations. To facilitate the measurement of brain tissue loss we developed novel algorithms which automatically separate the areas of brain tissue from the surrounding image background and identify the ventricles. We implemented these new algorithms by creating a new computer program (SectionToVolume which also has functions for image organization, image adjustments and volume calculations. We analyzed brain sections from mice subjected to severe focal TBI using both SectionToVolume and ImageJ, a commonly used image analysis program. The volume measurements made by the two programs were highly correlated and analysis using SectionToVolume required considerably less time. The inter-rater reliability was high. Given the extensive use of brain tissue loss measurements in TBI research, SectionToVolume will likely be a useful tool for TBI research. We therefore provide both the source code and the program as attachments to this article.

  7. Non-invasive measurement and validation of tissue oxygen saturation covered with overlying tissues

    Institute of Scientific and Technical Information of China (English)

    Yichao Teng; Haishu Ding; Lan Huang; Yue Li; Quanzhong Shan; Datian Ye; Haiyan Ding; Jenchung Chien; Betau Hwang

    2008-01-01

    In this paper,the biological tissue oxygen saturation(rS02)is obtained non-invasively and in real time based on near infrared spec-troscopy(NIRS)using two emitting wavelengths and two detectors,where the tissue is covered with overlying tissues.Our group devel-oped an NIRS oximeter based on the above principle independently,and validated it using liquid tissue model calibrations and animal experiments.The results indicate that(1)in the normal range of tissue oxygen saturation(40-70%),the rS02 measured by NIRS is accu-rate enough and little influenced by the background absorptions(such as the absorption of water)and overlying tissues(such as fat);(2)during cerebral hypoxia and recovery of three piglets,there is excellent correlation(p<0.001)between cerebral rS02 and jugular venous oxygen saturation(Sj02),meaning that the rS02 can be indicated by the Sj02 to a large extent;during the death of the three piglets induced by heart beat stopping,cerebral rS02 decreases continuously to significantly low levels(<25%)because cerebral blood supply does not exist any more.All the above results are of explicit physiological importance.

  8. Pesticide residues in brain tissues of dairy cattle in Lembang

    Directory of Open Access Journals (Sweden)

    Indraningsih

    2006-03-01

    Full Text Available The use of pesticides to control plant diseases may cause residual formation in crops, its byproduct and environmental. Furthermore, the use of agriculture byproduct as animal feed may cause poisoning or residual formation in animal products. The purpose of this study is to investigate of pesticide residues in brain tissues of dairy cattle in relation to animal feed as a contamination source. Samples consisted of animal feeds (19 samples of fodder and 6 samples of feed, 31 samples of sera and 25 samples of brain tissues of dairy cattle collected from Lembang, West Java. Feeds and fodders were collected from dairy farms located in Lembang. Sera were directly collected from 31 heads of Frisien Holstein (FH cattle from the same location, while brain tissues of FH cattle were collected from a local animal slaughtering house. Pesticide residues were analysed using gas chromatography (GC. Both residues of organochlorines and organophosphates were detected from brain tissues with average residue concentration OP was 22.7 ppb and OC was 5.1 ppb and a total residue was 27.8 ppb. The pesticide residues in brain tissues are new information that should be taken into consideration since the Indonesian consumed this tissues as an oval. Although pesticides residue concentration was low, pathological changes were noted microscopically from the brain tissues including extracellular vacuolisation, focal necrosis, haemorrhages, dilatation of basement membrane without cellular infiltration. Both pesticide residues were also detected in sera, where OP (9.0 ppb was higher than OC (4.9 ppb. These pesticides were also detected in animal feeds consisting fodders and feeds. Residues of OP (12.0 ppb were higher than OC (1.8 ppb in feeds, but residues of OP (16.8 ppb were lower than OC (18.7 ppb in fodders. Although, pesticide residues in sera and brain tissues were below the maximum residue limits (MRL of fat, the presence of pesticides in brain tissues should be taken

  9. Near-infrared oxymeter prototype for noninvasive analysis of rat brain oxygenation

    Science.gov (United States)

    Crespi, Francesco; Donini, Maurizio; Bandera, Andrea; Heidbreder, Christian; Salvatori, Giorgia; Rovati, Luigi

    2004-09-01

    The feasibility of non-invasive analysis of brain activities was studied in the attempt to overcome the major limitation of actual in vivo methodologies i.e. invasiveness. Optic fibre probes were used as optical head of a novel, highly sensitive near infrared continuous wave spectroscopy (CW-NIR) instrument. This prototype was designed for non-invasive analysis of the two main forms of haemoglobin: oxy-haemoglobin (HbO2) and deoxy-haemoglobin (Hb), chromophores present in biological tissues. It was tested in peripheral tissue (human gastrocnemius muscle) and then reset to perform measurement on rat brain. In animal studies, the optical head was firmly placed using stereotaxic apparatus upon the sagittal line of anaesthetised adult rat's head, without any surgery. Then pharmacological treatments with saline (300μl s.c.) amphetamine (2mg/kg) or nicotine (0.4mg/kg) were performed. Within 10-20 min amphetamine substantially increased HbO2 and reduced Hb control levels. Nicotine produced a rapid initial increase followed by a decrease of HbO2. In contrast to amphetamine, nicotine treatment also reduced Hb and blood volume. These results support the capacity of our CW-NIR prototype to measure non-invasively HbO2 and Hb levels in the rat brain, markers of the degree of tissue oxygenation, index of blood level then of the state of brain metabolism.

  10. Brain tumor imaging of rat fresh tissue using terahertz spectroscopy

    Science.gov (United States)

    Yamaguchi, Sayuri; Fukushi, Yasuko; Kubota, Oichi; Itsuji, Takeaki; Ouchi, Toshihiko; Yamamoto, Seiji

    2016-07-01

    Tumor imaging by terahertz spectroscopy of fresh tissue without dye is demonstrated using samples from a rat glioma model. The complex refractive index spectrum obtained by a reflection terahertz time-domain spectroscopy system can discriminate between normal and tumor tissues. Both the refractive index and absorption coefficient of tumor tissues are higher than those of normal tissues and can be attributed to the higher cell density and water content of the tumor region. The results of this study indicate that terahertz technology is useful for detecting brain tumor tissue.

  11. Correlation of oxygenation and perfusion sensitive MRI with invasive micro probe measurements in healthy mice brain.

    Science.gov (United States)

    Sedlacik, Jan; Reitz, Matthias; Bolar, Divya S; Adalsteinsson, Elfar; Schmidt, Nils O; Fiehler, Jens

    2015-03-01

    The non-invasive assessment of (patho-)physiological parameters such as, perfusion and oxygenation, is of great importance for the characterization of pathologies e.g., tumors, which may be helpful to better predict treatment response and potential outcome. To better understand the influence of physiological parameters on the investigated oxygenation and perfusion sensitive MRI methods, MRI measurements were correlated with subsequent invasive micro probe measurements during free breathing conditions of air, air+10% CO2 and 100% O2 in healthy mice brain. MRI parameters were the irreversible (R2), reversible (R2') and effective (R2*) transverse relaxation rates, venous blood oxygenation level assessed by quantitative blood oxygenation level dependent (qBOLD) method and cerebral blood flow (CBF) assessed by arterial spin labeling (ASL) using a 7 T small animal MRI scanner. One to two days after MRI, tissue perfusion and pO2 were measured by Laser-Doppler flowmetry and fluorescence quenching micro probes, respectively. The tissue pO2 values were converted to blood oxygen saturation by using the Hill equation. The animals were anesthetized by intra peritoneal injection of ketamine-xylazine-acepromazine (10-2-0.3 mg/ml · kg). Results for normal/hypercapnia/hyperoxia conditions were: R2[s(∧)-1] = 20.7/20.4/20.1, R2*[s(∧)-1] = 31.6/29.6/25.9, R2'[s-(∧)1] = 10.9/9.2/5.7, qBOLD venous blood oxygenation level = 0.43/0.51/0.56, CBF[ml · min(∧)-1 · 100 g(∧)-1] = 70.6/105.5/81.8, Laser-Doppler flowmetry[a.u.] = 89.2/120.2/90.6 and pO2[mmHg] = 6.3/32.3/46.7. All parameters were statistically significantly different with P oxygen saturation = 0.02/0.34/0.63, showed only very limited agreement with the qBOLD venous blood oxygenation level. We found good correlation between MRI and micro probe measurements. However, direct conversion of tissue pO2 to blood oxygen saturation by using the Hill equation is very limited. Furthermore, adverse effects of anesthesia and

  12. T2 and T2* measurements of fetal brain oxygenation during hypoxia with MRI at 3T: correlation with fetal arterial blood oxygen saturation

    International Nuclear Information System (INIS)

    The purpose of this prospective study was to determine the oxygen saturation of blood in the fetal brain based on T2 and T2* measurements in a fetal sheep model. Five sheep fetuses were investigated during normoxia and hypoxia by 3T MRI. Multi-echo gradient-echo and turbo-spin-echo sequences were performed on the fetal brain. MR-determined oxygen saturation (MR-sO2) of blood in the fetal brain was calculated based on T2 and T2* values. Fetal arterial blood oxygen saturation (blood-sO2) was measured during the two experimental phases. The slope of MR-sO2 as a function of blood-sO2 was estimated and tested for compatibility using the one-sample t-test. During normoxia, mean values for carotid blood oxygen saturation were 67%, 83 ms for T2*, 202 ms for T2 and 96% for MR-sO2. During hypoxia, arterial blood oxygen saturation, T2* and calculated MR-sO2 decreased to 22%, 64 ms, and 68% respectively. The one-sample t-test revealed the slope to be significantly different from 0(T=5.023, df=4, P=0.007). It is feasible to perform quantitative T2 and T2* measurements in the fetal brain. MR-sO2 and fetal arterial blood oxygen saturation correlated significantly. However, based on these data a reliable quantification of fetal brain tissue oxygenation is not possible. (orig.)

  13. T2 and T2* measurements of fetal brain oxygenation during hypoxia with MRI at 3T: correlation with fetal arterial blood oxygen saturation

    Energy Technology Data Exchange (ETDEWEB)

    Wedegaertner, Ulrike; Adam, Gerhard [Universitaetsklinikum Hamburg-Eppendorf, Department of Diagnostic and Interventional Radiology, Hamburg (Germany); Kooijman, Hendrik [Philips Medical Systems, Best (Netherlands); Andreas, Thomas; Beindorff, Nicola; Hecher, Kurt [University Hospital Hamburg-Eppendorf, Department of Obstetrics and Prenatal Medicine, Hamburg (Germany)

    2010-01-15

    The purpose of this prospective study was to determine the oxygen saturation of blood in the fetal brain based on T2 and T2* measurements in a fetal sheep model. Five sheep fetuses were investigated during normoxia and hypoxia by 3T MRI. Multi-echo gradient-echo and turbo-spin-echo sequences were performed on the fetal brain. MR-determined oxygen saturation (MR-sO{sub 2}) of blood in the fetal brain was calculated based on T2 and T2* values. Fetal arterial blood oxygen saturation (blood-sO{sub 2}) was measured during the two experimental phases. The slope of MR-sO{sub 2} as a function of blood-sO{sub 2} was estimated and tested for compatibility using the one-sample t-test. During normoxia, mean values for carotid blood oxygen saturation were 67%, 83 ms for T2*, 202 ms for T2 and 96% for MR-sO{sub 2}. During hypoxia, arterial blood oxygen saturation, T2* and calculated MR-sO{sub 2} decreased to 22%, 64 ms, and 68% respectively. The one-sample t-test revealed the slope to be significantly different from 0(T=5.023, df=4, P=0.007). It is feasible to perform quantitative T2 and T2* measurements in the fetal brain. MR-sO{sub 2} and fetal arterial blood oxygen saturation correlated significantly. However, based on these data a reliable quantification of fetal brain tissue oxygenation is not possible. (orig.)

  14. Brain Abscess After Soft Tissue Infection

    OpenAIRE

    Akoz A et al.

    2013-01-01

    The brain abscess, which is a focal intracerebral infection, is one of the serious complications of the head infections. It generally occurs in the immunocompromised patients due to the spreading from another infection focus on the body. It can be seen with the findings such as fever, headache, nausea, vomiting, diplopia, dysarthria and paralysis. Imaging methods are used in the diagnosis. In its treatment, antibiotherapy and surgical methods can be used. S...

  15. Even mild respiratory distress alters tissue oxygenation significantly in preterm infants during neonatal transition

    International Nuclear Information System (INIS)

    Near-infrared spectroscopy (NIRS) enables continuous non-invasive measurements of regional oxygen saturation (rSO2). The aim was to evaluate the dynamics of rSO2 of the brain, preductal and postductal tissues during postnatal transition in preterm infants with and without respiratory support (RS). This single-centre study was designed as an exploratory prospective observational study. Fifty one preterm infants (≥ 30 + 0 and < 37 + 0 weeks) delivered by caesarean section were included. RS using a T-Piece-Resuscitator and supplemental oxygen were given according to guidelines. NIRS measurements were carried out by using Invos Monitor (Covidien; USA) for the first 15 min of life. Three NIRS transducers were attached on the forehead (rSO2brain), the right forearm (rSO2arm) and the left lower leg (rSO2leg). Two groups were compared based on need for RS: normal transition (NT) and RS group. Results: In NT group rSO2brain increased over time and was significantly higher than rSO2arm, whereas in RS group rSO2brain and rSO2arm increased without significant differences. Courses of rSO2arm and rSO2leg increased over time and showed a converging pattern with initially lower values of rSO2leg in NT group and a diverging pattern with lower levels of rSO2leg in RS group. Overall, rSO2 levels were higher in NT compared to RS group. Conclusion: Our findings indicate that the decreased rSO2 levels in RS group compared to NT group are not only caused by lower arterial oxygen saturation levels, but also by a compromised perfusion even in infants with only mild respiratory distress. (paper)

  16. Neonatal brain injury as a consequence of insufficient cerebral oxygenation.

    Science.gov (United States)

    Placha, Katerina; Luptakova, Dominika; Baciak, Ladislav; Ujhazy, Eduard; Juranek, Ivo

    2016-01-01

    Neonatal brain hypoxic-ischemic injury represents a serious health care and socio-economical problem since it is one of the most common causes of mortality and morbidity of newborns. Neonatal hypoxic-ischemic encephalopathy is often associated with signs of perinatal asphyxia, with an incidence of about 2-4 per 1,000 live births and mortality rate up to 20%. In about one half of survivors, cerebral hypoxic-ischemic insult may result in more or less pronounced neuro-psychological sequelae of immediate or delayed nature, such as seizures, cerebral palsy or behavioural and learning disabilities, including attention-deficit hyperactivity disorder. Hypoxic-ischemic injury develops as a consequence of transient or permanent restriction of blood supply to the brain. Severity of hypoxic-ischemic encephalopathy varies depending on the intensity and duration of hypoxia-ischemia, on the type and size of the brain region affected, and on the maturity of the foetal/neonatal brain. Though a primary cause of hypoxic-ischemic injury is lack of oxygen in the neonatal brain, underlying mechanisms of subsequent events that are critical for developing hypoxic-ischemic encephalopathy are less understood. Their understanding is however necessary for elaborating effective management for newborns that underwent cerebral hypoxic-ischemic insult and thus are at risk of a negative outcome. The present paper summarizes current knowledge on cerebral hypoxic-ischemic injury of the neonate, fundamental processes involved in etiopathogenesis, with a special focus on cellular and molecular mechanisms and particular attention on certain controversial aspects of oxidative stress involvement. PMID:27179569

  17. Measuring the local electrical conductivity of human brain tissue

    Science.gov (United States)

    Akhtari, M.; Emin, D.; Ellingson, B. M.; Woodworth, D.; Frew, A.; Mathern, G. W.

    2016-02-01

    The electrical conductivities of freshly excised brain tissues from 24 patients were measured. The diffusion-MRI of the hydrogen nuclei of water molecules from regions that were subsequently excised was also measured. Analysis of these measurements indicates that differences between samples' conductivities are primarily due to differences of their densities of solvated sodium cations. Concomitantly, the sample-to-sample variations of their diffusion constants are relatively small. This finding suggests that non-invasive in-vivo measurements of brain tissues' local sodium-cation density can be utilized to estimate its local electrical conductivity.

  18. Coronaviruses in brain tissue from patients with multiple sclerosis

    DEFF Research Database (Denmark)

    Dessau, R B; Lisby, G; Frederiksen, J L

    2001-01-01

    Brain tissue from 25 patients with clinically definite multiple sclerosis (MS) and as controls brain tissue from 36 patients without neurological disease was tested for the presence of human coronaviral RNA. Four PCR assays with primers specific for N-protein of human coronavirus strain 229E...... and three PCR assays with primers specific for the nucleocapsid protein of human coronavirus strain OC43 were performed. Sporadic positive PCR assays were observed in both patients and controls in some of the PCR assays. However, these results were not reproducible and there was no difference...

  19. Impacts of Shisiwei Jianzhong Decoction on the Convulsion Latency and the Content of Cytokines in Brain Tissue of the Mice with Oxygen Convulsion%十四味建中汤对氧惊厥小鼠惊厥潜伏期及脑组织炎症细胞因子含量的影响

    Institute of Scientific and Technical Information of China (English)

    雷箴; 王国忠

    2015-01-01

    Objective To discuss the impacts and significance of shisiwei jianzhong decoction on convulsion latency and the content of IL - 1β and IL - 10 in brain tissue of the mice with oxygen convulsion. Methods Fifty - six mice were randomized into 7 groups,named an oxygen - convulsion 6 h group(6 h group),a 24 h group,a 48 h group,a shisiwei jianzhong decoction + oxygen - convulsion 6 h group(a therapy 6 h group),a therapy 24 h group,a therapy 48group and a normal control group. In all of the therapy groups, 2 weeks before convulsion induced by oxygen,shishiwei jianzhong decoction was used for gastric perfusion, once every day. The mice in all of the oxygen convulsion groups and the therapy groups were placed in 500 kPa oxygen environment till the seizure so as to prepare the model of oxygen convulsion. The enzyme - linked immunosorbent assay was used to detect the content of IL - 1β and IL - 10 in brain tissue. Results There was no significant difference in convulsion latency between the therapy groups and the oxygen convulsion groups(P ﹥ 0. 05). In the 24 h group and the 48 h group,the content of IL - 1β was higher significantly than that in the normal control group,indicating the significant difference(P ﹤ 0. 05),and that in the therapy 24 h group and the therapy 48 h group was lower significantly than that in the corresponding oxygen convulsion groups of the same time point,indicating the significant difference in the pair comparison(P ﹤ 0. 05). At the same time point,the difference in the content of IL - 10 was not significant among the oxygen convulsion groups,the therapy groups and the normal control group(P ﹥ 0. 05). Conclusion Shisiwei jianzhong decoc-tion does not significantly prolong the latency of oxygen convulsion in the mice,but it effectively reduces the content of IL - 1β,benefits the re - balance of proinflammatory cytokine and anti - inflammatory cytokine and alleviates the convulsive brain damage.%目的:探讨十四味建中汤对氧惊

  20. High-throughput single-cell manipulation in brain tissue.

    Directory of Open Access Journals (Sweden)

    Joseph D Steinmeyer

    Full Text Available The complexity of neurons and neuronal circuits in brain tissue requires the genetic manipulation, labeling, and tracking of single cells. However, current methods for manipulating cells in brain tissue are limited to either bulk techniques, lacking single-cell accuracy, or manual methods that provide single-cell accuracy but at significantly lower throughputs and repeatability. Here, we demonstrate high-throughput, efficient, reliable, and combinatorial delivery of multiple genetic vectors and reagents into targeted cells within the same tissue sample with single-cell accuracy. Our system automatically loads nanoliter-scale volumes of reagents into a micropipette from multiwell plates, targets and transfects single cells in brain tissues using a robust electroporation technique, and finally preps the micropipette by automated cleaning for repeating the transfection cycle. We demonstrate multi-colored labeling of adjacent cells, both in organotypic and acute slices, and transfection of plasmids encoding different protein isoforms into neurons within the same brain tissue for analysis of their effects on linear dendritic spine density. Our platform could also be used to rapidly deliver, both ex vivo and in vivo, a variety of genetic vectors, including optogenetic and cell-type specific agents, as well as fast-acting reagents such as labeling dyes, calcium sensors, and voltage sensors to manipulate and track neuronal circuit activity at single-cell resolution.

  1. Chemoselective imaging of mouse brain tissue via multiplex CARS microscopy

    OpenAIRE

    Pohling, Christoph; Buckup, Tiago; Pagenstecher, Axel; Motzkus, Marcus

    2011-01-01

    The fast and reliable characterization of pathological tissue is a debated topic in the application of vibrational spectroscopy in medicine. In the present work we apply multiplex coherent anti-Stokes Raman scattering (MCARS) to the investigation of fresh mouse brain tissue. The combination of imaginary part extraction followed by principal component analysis led to color contrast between grey and white matter as well as layers of granule and Purkinje cells. Additional quantitative informatio...

  2. Single-photon emission computed tomography and positron-emission tomography assays for tissue oxygenation.

    Science.gov (United States)

    Chapman, J D; Schneider, R F; Urbain, J L; Hanks, G E

    2001-01-01

    Radiotherapy prescription can now be customized to target the major mechanism(s) of resistance of individual tumors. In that regard, functional imaging techniques should be exploited to identify the dominant mechanism(s). Tumor biology research has identified several mechanisms of tumor resistance that may be unique to radiation treatments. These fall into 3 broad areas associated with (1) tumor hypoxic fraction, (2) tumor growth rate, (3) and the intrinsic radiosensitivity of tumor clonogens. Imaging research has markers in various stages of development for quantifying relevant information about each of these mechanisms, and those that measure tumor oxygenation and predict for radioresistance are the most advanced. Positron-emission tomography (PET) measurement of oxygen 15 has yielded important information, particularly about brain tissue perfusion, metabolism, and function. Indirect markers of tumor hypoxia have exploited the covalent binding of bioreductive intermediates of azomycin-containing compounds whose uptakes are inversely proportional to intracellular oxygen concentrations. Pilot clinical studies with single-photon emission computed tomography (SPECT) and PET detection of radiolabeled markers to tumor hypoxia have been reported. Recently, other studies have attempted to exploit the reduction properties of both technetium and copper chelates for the selective deposition of radioactive metals in hypoxic tissues. A growing number of potentially useful isotopes are now available for labeling several novel chemicals that could have the appropriate specificity and sensitivity. Preclinical studies with "microSPECT" and "microPET" will be important to define the optimal radiodiagnostic(s) for measuring tissue oxygenation and for determining the time after their administration for optimal hypoxic signal acquisition. Radiolabeled markers of growth kinetics and intrinsic radiosensitivity of cells in solid tumors are also being developed. We conclude that

  3. Effect of mild hypothermia on glucose metabolism and glycerol of brain tissue in patients with severe traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    WANG Qiong; LI Ai-lin; ZHI Da-shi; HUANG Hui-ling

    2007-01-01

    Objective:To study the effect of mild hypothermia on glucose metabolism and glycerol of brain tissue in patients with severe traumatic brain injury (STBI) using clinical microdialysis.Methods: Thirty-one patients with STBI ( GCS ≤8) were randomly divided into hypothermic group (Group A) and control group (Group B). Microdialysis catheters were inserted into the cerebral cortex of perilesional and normal brain tissue. All samples were analyzed using CMA microdialysis analyzer.Results: In comparison with the control group, lactate/glucose ratio ( L/G) , lactate/pyruvate ratio ( L/P) and glycerol (Gly) in perilensional tissue were significantly decreased; L/P in normal brain tissue was significantly decreased. In control group, L/G, L/P and Gly in perilensional tissue were higher than that in normal brain tissue. In the hypothermic group, L/P in perilensional tissue was higher than that in relative normal brain.Conclusions: Mild hypothermia protects brain tissues by decreasing L/G, L/P and Gly in perilensional tissue and L/P in "normal brain" tissues. The energy crisis and membrane phospholipid degradation in perilensional tissue are easier to happen after traumatic brain injury, and mild hypothermia protects brain better in perilensional tissue than in normal brain tissue.

  4. Development of an ultrasound sensitive oxygen carrier for oxygen delivery to hypoxic tissue.

    Science.gov (United States)

    Eisenbrey, John R; Albala, Lorenzo; Kramer, Michael R; Daroshefski, Nick; Brown, David; Liu, Ji-Bin; Stanczak, Maria; O'Kane, Patrick; Forsberg, Flemming; Wheatley, Margaret A

    2015-01-15

    Radiation therapy is frequently used in the treatment of malignancies, but tumors are often more resistant than the surrounding normal tissue to radiation effects, because the tumor microenvironment is hypoxic. This manuscript details the fabrication and characterization of an ultrasound-sensitive, injectable oxygen microbubble platform (SE61O2) for overcoming tumor hypoxia. SE61O2 was fabricated by first sonicating a mixture of Span 60 and water-soluble vitamin E purged with perfluorocarbon gas. SE61O2 microbubbles were separated from the foam by flotation, then freeze dried under vacuum to remove all perfluorocarbon, and reconstituted with oxygen. Visually, SE61O2 microbubbles were smooth, spherical, with an average diameter of 3.1 μm and were reconstituted to a concentration of 6.5 E7 microbubbles/ml. Oxygen-filled SE61O2 provides 16.9 ± 1.0 dB of enhancement at a dose of 880 μl/l (5.7 E7 microbubbles/l) with a half-life under insonation of approximately 15 min. In in vitro release experiments, 2 ml of SE61O2 (1.3 E8 microbubbles) triggered with ultrasound was found to elevate oxygen partial pressures of 100ml of degassed saline 13.8 mmHg more than untriggered bubbles and 20.6 mmHg more than ultrasound triggered nitrogen-filled bubbles. In preliminary in vivo delivery experiments, triggered SE61O2 resulted in a 30.4 mmHg and 27.4 mmHg increase in oxygen partial pressures in two breast tumor mouse xenografts. PMID:25448552

  5. A High Rate Tension Device for Characterizing Brain Tissue

    CERN Document Server

    Rashid, Badar; Gilchrist, Michael; 10.1177/1754337112436900

    2013-01-01

    The mechanical characterization of brain tissue at high loading velocities is vital for understanding and modeling Traumatic Brain Injury (TBI). The most severe form of TBI is diffuse axonal injury (DAI) which involves damage to individual nerve cells (neurons). DAI in animals and humans occurs at strains > 10% and strain rates > 10/s. The mechanical properties of brain tissues at these strains and strain rates are of particular significance, as they can be used in finite element human head models to accurately predict brain injuries under different impact conditions. Existing conventional tensile testing machines can only achieve maximum loading velocities of 500 mm/min, whereas the Kolsky bar apparatus is more suitable for strain rates > 100/s. In this study, a custom-designed high rate tension device is developed and calibrated to estimate the mechanical properties of brain tissue in tension at strain rates < 90/s, while maintaining a uniform velocity. The range of strain can also be extended to 100% de...

  6. Discovery of Undescribed Brain Tissue Changes Around Implanted Microelectrode Arrays

    Directory of Open Access Journals (Sweden)

    Himanshi Desai

    2012-01-01

    Full Text Available Brain-implantable microelectrode arrays are devicesdesigned to record or electrically stimulate the activity ofneurons in the brain. These devices hold the potential tohelp treat epilepsy, paralysis, blindness, and deafness, andalso provide researchers with insights into a varietyof neural processes, such as memory formation.While these devices have a very promising future,researchers are discovering that their long-termfunctionality is greatly limited by the brain’s naturalimmune response to foreign objects. To improve thefunctional lifetime of these devices, one solution lies infully characterizing and understanding this tissue response.Roles for microglia and astrocytes in this biologicalresponse have been characterized. However, changesto oligodendrocytes, cells that myelinate axons, remainpoorly understood. These cells provide insulationto the axons, which is required for proper neuralfunctioning. Here we report on the changes that occurwith oligodendrocyte processes in tissue aroundmicroelectrode implants in the brain.Six rats were surgically implanted with microelectrodearrays and allowed to recover for 1, 2, or 4 weeks.Subjects were then sacrificed and the brain tissue wasprocessed using our recently developed method, Device-Capture Histology. Immunohistochemistry and confocalmicroscopy was employed to assess the responsearound the device. Results indicated a decrease inoligodendrocyte density and a loss in typical directionalorientation of oligodendrocyte processes in tissue near thedevice. These results suggest alterations in the underlyingneuronal networks around these devices, which maygreatly impact the current functional utility of thesepromising devices.

  7. Change in tissue thromboplastin content of brain following trauma

    Directory of Open Access Journals (Sweden)

    Pathak Ashis

    2005-01-01

    Full Text Available Background: Tissue thromboplastin (TTP is an integral membrane protein contributing to coagulopathy after trauma of brain, which is a rich source of TTP. Aims: A study was undertaken to establish the TTP content of various areas of normal brain and estimate the changes in TTP activity of brain in response to varying degrees of trauma. Materials and Methods: Samples from different areas of brain of ten cadavers were used as controls and they were compared with contused brain tissue obtained after surgery in 25 head injury (HI patients of varying severity. Results: In the study group, the TTP activity of the frontal, parietal, and temporal lobes after HI was significantly raised in contrast to that of the control group. The TTP activity was also significantly higher in the severe HI patients than those having moderate HI. The mode of injury and the time lapse after HI had no significant bearing on the TTP activity. Subjects above 40 years of age demonstrated a higher mean TTP activity after HI, though it was not statistically significant. Conclusion: The study provides quantitative data on TTP activity of normal brain and highlights the role of TTP in coagulopathy following HI through its increased activity after HI, more so in the severe HI group.

  8. Blood Flow Versus Hematocrit in Optimization of Oxygen Transfer to Tissue During Fluid Resuscitation.

    Science.gov (United States)

    Siam, Jamal; Kadan, Marwa; Flaishon, Ron; Barnea, Ofer

    2015-12-01

    The effectiveness of fluid resuscitation regimens in hemorrhagic trauma is assessed based on its ability to increase oxygen concentration in tissue. Fluid resuscitation using both crystalloids and colloids fluids, creates a dilemma due to its opposing effects on oxygen transfer. It increases blood flow thereby augmenting oxygen transport but it also dilutes the blood simultaneously and reduces oxygen concentration thereby reducing oxygen transport. In this work we have studied these two opposing effects of fluid therapy on oxygen delivery to tissue. A mathematical model of oxygen diffusion from capillaries to tissue and its distribution in tissue was developed and integrated into a previously developed hemodynamic model. The capillary-tissue model was based on the Krogh structure. Compared to other models, fewer simplifying assumptions were made leading to different boundary conditions and less constraints, especially regarding capillary oxygen content at its venous end. Results showed that oxygen content in blood is the dominant factor in oxygen transport to tissue and its effect is greater than the effect of flow. The integration of the capillary/tissue model with the hemodynamic model that links administered fluids with flow and blood dilution indicated that fluid resuscitation may reduce oxygen transport to tissue.

  9. General solutions to poroviscoelastic model of hydrocephalic human brain tissue.

    Science.gov (United States)

    Mehrabian, Amin; Abousleiman, Younane

    2011-12-21

    Hydrocephalus is a well-known disorder of brain fluidic system. It is commonly associated with complexities in cerebrospinal fluid (CSF) circulation in brain. In this paper, hydrocephalus and shunting surgery which is used in its treatment are modeled. Brain tissues are considered to follow a poroviscoelastic constitutive model in order to address the effects of time dependence of mechanical properties of soft tissues and fluid flow hydraulics. Our solution draws from Biot's theory of poroelasticity, generalized to account for viscoelastic effects through the correspondence principle. Geometrically, the brain is conceived to be spherically symmetric, where the ventricles are assumed to be a hollow concentric space filled with cerebrospinal fluid. A generalized Kelvin model is considered for the rheological properties of brain tissues. The solution presented is useful in the analysis of the disorder of hydrocephalus as well as the treatment associated with it, namely, ventriclostomy surgery. The sensitivity of the solution to various factors such as aqueduct blockage level and trabeculae stiffness is thoroughly analyzed using numerical examples. Results indicate that partial aqueduct stenosis may be a cause of hydrocephalus. However, only severe occlusion of the aqueduct can cause a significant increase in the ventricle and brain's extracellular fluid pressure. Ventriculostomy shunts are commonly used as a remedy to hydrocephalus. They serve to reduce the ventricular pressure to the normal level. However, sensitivity analysis on the shunt's fluid deliverability parameter has shown that inappropriate design or selection of design shunt may cause under-drainage or over-drainage of the ventricles. Excessive drainage of CSF may increase the normal tensile stress on trabeculae. It can cause rupture of superior cerebral veins or damage to trabeculae or even brain tissues which in turn may lead to subdural hematoma, a common side-effect of the surgery. These Post

  10. Neonatal Brain Tissue Classification with Morphological Adaptation and Unified Segmentation

    Directory of Open Access Journals (Sweden)

    Richard eBeare

    2016-03-01

    Full Text Available Measuring the distribution of brain tissue types (tissue classification in neonates is necessary for studying typical and atypical brain development, such as that associated with preterm birth, and may provide biomarkers for neurodevelopmental outcomes. Compared with magnetic resonance images of adults, neonatal images present specific challenges that require the development of specialized, population-specific methods. This paper introduces MANTiS (Morphologically Adaptive Neonatal Tissue Segmentation, which extends the unified segmentation approach to tissue classification implemented in Statistical Parametric Mapping (SPM software to neonates. MANTiS utilizes a combination of unified segmentation, template adaptation via morphological segmentation tools and topological filtering, to segment the neonatal brain into eight tissue classes: cortical gray matter, white matter, deep nuclear gray matter, cerebellum, brainstem, cerebrospinal fluid (CSF, hippocampus and amygdala. We evaluated the performance of MANTiS using two independent datasets. The first dataset, provided by the NeoBrainS12 challenge, consisted of coronal T2-weighted images of preterm infants (born ≤30 weeks’ gestation acquired at 30 weeks’ corrected gestational age (n= 5, coronal T2-weighted images of preterm infants acquired at 40 weeks’ corrected gestational age (n= 5 and axial T2-weighted images of preterm infants acquired at 40 weeks’ corrected gestational age (n= 5. The second dataset, provided by the Washington University NeuroDevelopmental Research (WUNDeR group, consisted of T2-weighted images of preterm infants (born <30 weeks’ gestation acquired shortly after birth (n= 12, preterm infants acquired at term-equivalent age (n= 12, and healthy term-born infants (born ≥38 weeks’ gestation acquired within the first nine days of life (n= 12. For the NeoBrainS12 dataset, mean Dice scores comparing MANTiS with manual segmentations were all above 0.7, except for

  11. Correlation of cutaneous tension distribution and tissue oxygenation with acute external tissue expansion

    Directory of Open Access Journals (Sweden)

    Marquardt C

    2009-11-01

    Full Text Available Abstract Today, the biomechanical fundamentals of skin expansion are based on viscoelastic models of the skin. Although many studies have been conducted in vitro, analyses performed in vivo are rare. Here, we present in vivo measurements of the expansion at the skin surface as well as measurement of the corresponding intracutaneous oxygen partial pressure. In our study the average skin stretching was 24%, with a standard deviation of 11%, excluding age or gender dependency. The measurement of intracutaneous oxygen partial pressure produced strong inter-individual fluctuations, including initial values at the beginning of the measurement, as well as varying individual patient reactions to expansion of the skin. Taken together, we propose that even large defect wounds can be closed successfully using the mass displacement caused by expansion especially in areas where soft, voluminous tissue layers are present.

  12. Transistor needle chip for recording in brain tissue

    Science.gov (United States)

    Felderer, Florian; Fromherz, Peter

    2011-07-01

    We report on a proof-of-principle experiment for the direct interfacing of transistors with intact brain tissue. A transistor needle chip (TNC) with a TiO2 surface is fabricated from a silicon-on-insulator wafer and impaled into an acute brain slice cut from hippocampus of the rat. While stimulating the Schaffer collateral, a local field potential is recorded in stratum radiatum of the CA1 region with field-effect transistors in the central part of the slice where the tissue is not damaged by the cutting process. After the impalement, the signal amplitude is small. Within an hour, it increases to a stable level around -2 mV as is recorded with a conventional micropipette electrode. The recovery indicates that the tissue is able to adapt to the impaled chip. Upon repeated impalements at the same position, the large signal is observed without delay. A profile of the transistor signal across the slice is due to the boundary conditions of a brain slice with both surfaces held near ground potential. The experiments with the TNC prototype are a basis for the development of silicon needle chips with a large multi-transistor array (MTA) for applications in brain-computer interfacing.

  13. Determination of Friction Coefficient in Unconfined Compression of Brain Tissue

    CERN Document Server

    Rashid, Badar; Gilchrist, Michael; 10.1016/j.jmbbm.2012.05.001

    2013-01-01

    Unconfined compression tests are more convenient to perform on cylindrical samples of brain tissue than tensile tests in order to estimate mechanical properties of the brain tissue because they allow for homogeneous deformations. The reliability of these tests depends significantly on the amount of friction generated at the specimen/platen interface. Thus, there is a crucial need to find an approximate value of the friction coefficient in order to predict a possible overestimation of stresses during unconfined compression tests. In this study, a combined experimental-computational approach was adopted to estimate the dynamic friction coefficient mu of porcine brain matter against metal platens in compressive tests. Cylindrical samples of porcine brain tissue were tested up to 30% strain at variable strain rates, both under bonded and lubricated conditions in the same controlled environment. It was established that mu was equal to 0.09 +/- 0.03, 0.18 +/- 0.04, 0.18 +/- 0.04 and 0.20 +/- 0.02 at strain rates of...

  14. Correlation of oxygenation and perfusion sensitive MRI with invasive micro probe measurements in healthy mice brain

    Energy Technology Data Exchange (ETDEWEB)

    Sedlacik, Jan; Fiehler, Jens [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Neuroradiology; Reitz, Matthias; Schmidt, Nils O. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Neurosurgery; Bolar, Divya S. [Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA (United States). Radiology; Adalsteinsson, Elfar [Massachusetts Institute of Technology, Cambridge, MA (United States). Electrical Engineering and Computer Science

    2015-05-01

    The non-invasive assessment of (patho-)physiological parameters such as, perfusion and oxygenation, is of great importance for the characterization of pathologies e.g., tumors, which may be helpful to better predict treatment response and potential outcome. To better understand the influence of physiological parameters on the investigated oxygenation and perfusion sensitive MRI methods, MRI measurements were correlated with subsequent invasive micro probe measurements during free breathing conditions of air, air+10% CO2 and 100% O2 in healthy mice brain. MRI parameters were the irreversible (R2), reversible (R2') and effective (R2*) transverse relaxation rates, venous blood oxygenation level assessed by quantitative blood oxygenation level dependent (qBOLD) method and cerebral blood flow (CBF) assessed by arterial spin labeling (ASL) using a 7T small animal MRI scanner. One to two days after MRI, tissue perfusion and pO2 were measured by Laser-Doppler flowmetry and fluorescence quenching micro probes, respectively. The tissue pO2 values were converted to blood oxygen saturation by using the Hill equation. The animals were anesthetized by intra peritoneal injection of ketamine-xylazine-acepromazine (10-2-0.3 mg/ml.kg). Results for normal/hypercapnia/hyperoxia conditions were: R2[s {sup and} -1] = 20.7/20.4/20.1, R2*[s {sup and} -1] = 31.6/29.6/25.9, R2'[s {sup and} 1] = 10.9/9.2/5.7, qBOLD venous blood oxygenation level = 0.43/0.51/0.56, CBF[ml.min {sup and} -1.100g {sup and} -1] = 70.6/105.5/81.8, Laser-Doppler flowmetry[a.u.] = 89.2/120.2/90.6 and pO2[mmHg] = 6.3/32.3/46.7. All parameters were statistically significantly different with P < 0.001 between all breathing conditions. All MRI and the corresponding micro probe measurements were also statistically significantly (P ≤ 0.03) correlated with each other. However, converting the tissue pO2 to blood oxygen saturation = 0.02/0.34/0.63, showed only very limited agreement with the qBOLD venous blood

  15. Automatic segmentation of eight tissue classes in neonatal brain MRI.

    Directory of Open Access Journals (Sweden)

    Petronella Anbeek

    Full Text Available PURPOSE: Volumetric measurements of neonatal brain tissues may be used as a biomarker for later neurodevelopmental outcome. We propose an automatic method for probabilistic brain segmentation in neonatal MRIs. MATERIALS AND METHODS: In an IRB-approved study axial T1- and T2-weighted MR images were acquired at term-equivalent age for a preterm cohort of 108 neonates. A method for automatic probabilistic segmentation of the images into eight cerebral tissue classes was developed: cortical and central grey matter, unmyelinated and myelinated white matter, cerebrospinal fluid in the ventricles and in the extra cerebral space, brainstem and cerebellum. Segmentation is based on supervised pixel classification using intensity values and spatial positions of the image voxels. The method was trained and evaluated using leave-one-out experiments on seven images, for which an expert had set a reference standard manually. Subsequently, the method was applied to the remaining 101 scans, and the resulting segmentations were evaluated visually by three experts. Finally, volumes of the eight segmented tissue classes were determined for each patient. RESULTS: The Dice similarity coefficients of the segmented tissue classes, except myelinated white matter, ranged from 0.75 to 0.92. Myelinated white matter was difficult to segment and the achieved Dice coefficient was 0.47. Visual analysis of the results demonstrated accurate segmentations of the eight tissue classes. The probabilistic segmentation method produced volumes that compared favorably with the reference standard. CONCLUSION: The proposed method provides accurate segmentation of neonatal brain MR images into all given tissue classes, except myelinated white matter. This is the one of the first methods that distinguishes cerebrospinal fluid in the ventricles from cerebrospinal fluid in the extracerebral space. This method might be helpful in predicting neurodevelopmental outcome and useful for evaluating

  16. Automatic Segmentation of Eight Tissue Classes in Neonatal Brain MRI

    Science.gov (United States)

    Anbeek, Petronella; Išgum, Ivana; van Kooij, Britt J. M.; Mol, Christian P.; Kersbergen, Karina J.; Groenendaal, Floris; Viergever, Max A.; de Vries, Linda S.; Benders, Manon J. N. L.

    2013-01-01

    Purpose Volumetric measurements of neonatal brain tissues may be used as a biomarker for later neurodevelopmental outcome. We propose an automatic method for probabilistic brain segmentation in neonatal MRIs. Materials and Methods In an IRB-approved study axial T1- and T2-weighted MR images were acquired at term-equivalent age for a preterm cohort of 108 neonates. A method for automatic probabilistic segmentation of the images into eight cerebral tissue classes was developed: cortical and central grey matter, unmyelinated and myelinated white matter, cerebrospinal fluid in the ventricles and in the extra cerebral space, brainstem and cerebellum. Segmentation is based on supervised pixel classification using intensity values and spatial positions of the image voxels. The method was trained and evaluated using leave-one-out experiments on seven images, for which an expert had set a reference standard manually. Subsequently, the method was applied to the remaining 101 scans, and the resulting segmentations were evaluated visually by three experts. Finally, volumes of the eight segmented tissue classes were determined for each patient. Results The Dice similarity coefficients of the segmented tissue classes, except myelinated white matter, ranged from 0.75 to 0.92. Myelinated white matter was difficult to segment and the achieved Dice coefficient was 0.47. Visual analysis of the results demonstrated accurate segmentations of the eight tissue classes. The probabilistic segmentation method produced volumes that compared favorably with the reference standard. Conclusion The proposed method provides accurate segmentation of neonatal brain MR images into all given tissue classes, except myelinated white matter. This is the one of the first methods that distinguishes cerebrospinal fluid in the ventricles from cerebrospinal fluid in the extracerebral space. This method might be helpful in predicting neurodevelopmental outcome and useful for evaluating neuroprotective clinical

  17. Acute supramaximal exercise increases the brain oxygenation in relation to cognitive workload

    OpenAIRE

    Cem Seref Bediz; Adile eOniz; Cagdas eGuducu; Enise eUral Demirci; Hilmi eOgut; Erkan eGunay; Caner eCetinkaya; Murat eOzgoren

    2016-01-01

    Single bout of exercise can improve the performance on cognitive tasks. However, cognitive responses may be controversial due to different type, intensity, and duration of exercise. In addition, the mechanism of the effect of acute exercise on brain is still unclear. This study was aimed to investigate the effects of supramaximal exercise on cognitive tasks by means of brain oxygenation monitoring. The brain oxygenation of Prefrontal cortex (PFC) was measured on 35 healthy male volunteers via...

  18. Acute Supramaximal Exercise Increases the Brain Oxygenation in Relation to Cognitive Workload

    OpenAIRE

    Bediz, Cem Seref; Oniz, Adile; Guducu, Cagdas; Ural Demirci, Enise; Ogut, Hilmi; Gunay, Erkan; Cetinkaya, Caner; Ozgoren, Murat

    2016-01-01

    Single bout of exercise can improve the performance on cognitive tasks. However, cognitive responses may be controversial due to different type, intensity, and duration of exercise. In addition, the mechanism of the effect of acute exercise on brain is still unclear. This study was aimed to investigate the effects of supramaximal exercise on cognitive tasks by means of brain oxygenation monitoring. The brain oxygenation of Prefrontal cortex (PFC) was measured on 35 healthy male volunteers via...

  19. Inhomogeneous Deformation of Brain Tissue During Tension Tests

    CERN Document Server

    Rashid, Badar; Gilchrist, Michael D; 10.1016/j.commatsci.2012.05.030

    2013-01-01

    Mechanical characterization of brain tissue has been investigated extensively by various research groups over the past fifty years. These properties are particularly important for modelling Traumatic Brain Injury (TBI). In this research, we present the design and calibration of a High Rate Tension Device (HRTD) capable of performing tests up to a maximum strain rate of 90/s. We use experimental and numerical methods to investigate the effects of inhomogeneous deformation of porcine brain tissue during tension at different specimen thicknesses (4.0-14.0 mm), by performing tension tests at a strain rate of 30/s. One-term Ogden material parameters (mu = 4395.0 Pa, alpha = -2.8) were derived by performing an inverse finite element analysis to model all experimental data. A similar procedure was adopted to determine Young's modulus (E= 11200 Pa) of the linear elastic regime. Based on this analysis, brain specimens of aspect ratio (diameter/thickness) S < 1.0 are required to minimise the effects of inhomogeneous...

  20. Experimental studies on brain hematoma detection and oxygenation monitoring using PRM/NIR sensors

    Science.gov (United States)

    Zheng, Liu; Lee, Hyo Sang; Wilson, David A.; Hanley, Daniel F.; Lokos, Sandor; Kim, Jin

    1997-08-01

    Real time noninvasive head injury detection is needed in critical care facilities and triage site with limited resources. One tool missing right now is a small and fast noninvasive sensor which can help urgent care workers to (1) diagnose the location and severity of the injury, (2) to perform on site pre-hospital treatment if necessary, and (3) to make a decision on what kind of further medical action is needed. On the other hand, continuous monitoring of cerebral blood oxygenation is also needed in intensive care unit and in operation rooms. Pseudo-random modulation/near infrared sensor (PRM/NIR sensor) is developed to address these issues. It relies on advanced techniques in diode laser cw modulation and time resolved spectroscopy to perform fast and noninvasive brain tissue diagnostics. Phantom experiments have been conducted to study the feasibility of the sensor. Brain's optical properties are simulated with solutions of intralipid and ink. Hematomas are simulated with bags of paint and hemoglobin immersed in the solution of varies sizes, depths, and orientations. Effects of human skull and hair are studied experimentally. In animal experiment, the sensor was used to monitor the cerebral oxygenation change due to hypercapnia, hypoxia, and hyperventilation. Good correlations were found between NIR measurement parameters and physiological changes induced to the animals.

  1. Tissue-specific sparse deconvolution for brain CT perfusion.

    Science.gov (United States)

    Fang, Ruogu; Jiang, Haodi; Huang, Junzhou

    2015-12-01

    Enhancing perfusion maps in low-dose computed tomography perfusion (CTP) for cerebrovascular disease diagnosis is a challenging task, especially for low-contrast tissue categories where infarct core and ischemic penumbra usually occur. Sparse perfusion deconvolution has been recently proposed to effectively improve the image quality and diagnostic accuracy of low-dose perfusion CT by extracting the complementary information from the high-dose perfusion maps to restore the low-dose using a joint spatio-temporal model. However the low-contrast tissue classes where infarct core and ischemic penumbra are likely to occur in cerebral perfusion CT tend to be over-smoothed, leading to loss of essential biomarkers. In this paper, we propose a tissue-specific sparse deconvolution approach to preserve the subtle perfusion information in the low-contrast tissue classes. We first build tissue-specific dictionaries from segmentations of high-dose perfusion maps using online dictionary learning, and then perform deconvolution-based hemodynamic parameters estimation for block-wise tissue segments on the low-dose CTP data. Extensive validation on clinical datasets of patients with cerebrovascular disease demonstrates the superior performance of our proposed method compared to state-of-art, and potentially improve diagnostic accuracy by increasing the differentiation between normal and ischemic tissues in the brain.

  2. Tissue-specific sparse deconvolution for brain CT perfusion.

    Science.gov (United States)

    Fang, Ruogu; Jiang, Haodi; Huang, Junzhou

    2015-12-01

    Enhancing perfusion maps in low-dose computed tomography perfusion (CTP) for cerebrovascular disease diagnosis is a challenging task, especially for low-contrast tissue categories where infarct core and ischemic penumbra usually occur. Sparse perfusion deconvolution has been recently proposed to effectively improve the image quality and diagnostic accuracy of low-dose perfusion CT by extracting the complementary information from the high-dose perfusion maps to restore the low-dose using a joint spatio-temporal model. However the low-contrast tissue classes where infarct core and ischemic penumbra are likely to occur in cerebral perfusion CT tend to be over-smoothed, leading to loss of essential biomarkers. In this paper, we propose a tissue-specific sparse deconvolution approach to preserve the subtle perfusion information in the low-contrast tissue classes. We first build tissue-specific dictionaries from segmentations of high-dose perfusion maps using online dictionary learning, and then perform deconvolution-based hemodynamic parameters estimation for block-wise tissue segments on the low-dose CTP data. Extensive validation on clinical datasets of patients with cerebrovascular disease demonstrates the superior performance of our proposed method compared to state-of-art, and potentially improve diagnostic accuracy by increasing the differentiation between normal and ischemic tissues in the brain. PMID:26055434

  3. 自体血液回收联合控制性降压减少输血及对脑组织氧合和乳酸代谢的影响%Combined autologous transfusion with controlled hypotension to reduce blood transfusion and the influence on brain tissue oxygenation and lactate metabolism

    Institute of Scientific and Technical Information of China (English)

    侯南丽; 袁莉; 刘爱杰; 王世端; 武贞芝

    2014-01-01

    Objective To observe the effects of blood salvage and controlled hypotension which can reduce allogeneic blood transfusion on brain tissue oxygenation and lactic acid metabolism in patients with spinal surgery, and to determine the efficacy and safety of combination. Methods Sixty patients scheduled for spinal surgery with ASA grade I-Ⅱ levels in our hospital from December 2011 to May 2013 were randomly divided into two groups with 30 cases in each:Experimental Group (blood salvage combing controlled hypotension) or Control Group. General anesthesia was chosen in all patients. Blood samples were taken from the right jugular bulb and radial arterial simultaneously before surgery (T0), the end of surgery(T2) and 24 hours after surgery (T3) for blood gas analysis. Arterial oxygen partial pressure (PaO2), arterial oxygen saturation degree (SaO2), jugular bulb blood oxygen partial pressure (PjvO2), jugular bulb oxygen saturation (SjvO2), arterial and venous blood lactic acid (LacA, Lacjv) were recorded. Cerebral arterial oxygen content (CaO2), jugular bulb oxygen content (CjvO2), cerebral oxygen consumption C (ajv) O2 , cerebral oxygen uptake rate (CERO2) and difference in arterial and venous lactic acid content (ADVL) were calculated according to Fick formula. T1 is the stable point of intraoperative controlled hypotension. Patients' infusion volume,blood loss,autologous blood transfusion,allogeneic blood transfusion and the hemoglobin levels were recorded at each time point of these two groups. Results There was no significant difference in age, body weight, heart rate (HR), preoperative hemoglobin level (Hb) and preoperative coagulation index between two groups(P>0.05). Allogeneic blood transfusion volumes were significantly less in Experimental Group than those in Control Croup (P0.05). The CaO2, CjvO2 decreased significantly at the end of surgery(T2) and 24 hours after surgery (T3)compared with T0 (P0.05). Blood pressure was significantly lower in Control Group

  4. Hyperbaric oxygen treatment promotes neural stem cell proliferation in the subventricular zone of neonatal rats with hypoxic-ischemic brain damage

    Institute of Scientific and Technical Information of China (English)

    Zhichun Feng; Jing Liu; Rong Ju

    2013-01-01

    Hyperbaric oxygen therapy for the treatment of neonatal hypoxic-ischemic brain damage has been used clinically for many years, but its effectiveness remains controversial. In addition, the mechanism of this potential neuroprotective effect remains unclear. This study aimed to investigate the influence of hyperbaric oxygen on the proliferation of neural stem cells in the subventricular zone of neonatal Sprague-Dawley rats (7 days old) subjected to hypoxic-ischemic brain damage. Six hours after modeling, rats were treated with hyperbaric oxygen once daily for 7 days. Immunohistochemistry revealed that the number of 5-bromo-2′-deoxyuridine positive and nestin positive cells in the subventricular zone of neonatal rats increased at day 3 after hypoxic-ischemic brain damage and peaked at day 5. After hyperbaric oxygen treatment, the number of 5-bromo-2′- deoxyuridine positive and nestin positive cells began to increase at day 1, and was significantly higher than that in normal rats and model rats until day 21. Hematoxylin-eosin staining showed that hyperbaric oxygen treatment could attenuate pathological changes to brain tissue in neonatal rats, and reduce the number of degenerating and necrotic nerve cells. Our experimental findings indicate that hyperbaric oxygen treatment enhances the proliferation of neural stem cells in the subventricular zone of neonatal rats with hypoxic-ischemic brain damage, and has therapeutic potential for promoting neurological recovery following brain injury.

  5. Implementing oxygen control in chip-based cell and tissue culture systems.

    Science.gov (United States)

    Oomen, Pieter E; Skolimowski, Maciej D; Verpoorte, Elisabeth

    2016-09-21

    Oxygen is essential in the energy metabolism of cells, as well as being an important regulatory parameter influencing cell differentiation and function. Interest in precise oxygen control for in vitro cultures of tissues and cells continues to grow, especially with the emergence of the organ-on-a-chip and the desire to emulate in vivo conditions. This was recently discussed in this journal in a Critical Review by Brennan et al. (Lab Chip (2014). DOI: ). Microfluidics can be used to introduce flow to facilitate nutrient supply to and waste removal from in vitro culture systems. Well-defined oxygen gradients can also be established. However, cells can quickly alter the oxygen balance in their vicinity. In this Tutorial Review, we expand on the Brennan paper to focus on the implementation of oxygen analysis in these systems to achieve continuous monitoring. Both electrochemical and optical approaches for the integration of oxygen monitoring in microfluidic tissue and cell culture systems will be discussed. Differences in oxygen requirements from one organ to the next are a challenging problem, as oxygen delivery is limited by its uptake into medium. Hence, we discuss the factors determining oxygen concentrations in solutions and consider the possible use of artificial oxygen carriers to increase dissolved oxygen concentrations. The selection of device material for applications requiring precise oxygen control is discussed in detail, focusing on oxygen permeability. Lastly, a variety of devices is presented, showing the diversity of approaches that can be employed to control and monitor oxygen concentrations in in vitro experiments.

  6. O2 supplementation to secure the near-infrared spectroscopy determined brain and muscle oxygenation in vascular surgical patients: a presentation of 100 cases

    Directory of Open Access Journals (Sweden)

    Kim Zillo Rokamp

    2014-02-01

    Full Text Available This study addresses three questions for securing tissue oxygenation in brain (rScO2 and muscle (SmO2 for 100 patients (age 71 ± 6 yrs; mean ± SD undergoing vascular surgery: i Does preoxygenation (inhaling 100% oxygen before anesthesia increase tissue oxygenation, ii Does inhalation of 70% oxygen during surgery prevent a critical reduction in rScO2 (< 50%, and iii is a decrease in rScO2 and/or SmO2 related to reduced blood pressure and/or cardiac output? Intravenous anesthesia was provided to all patients and the intraoperative inspired oxygen fraction was set to 0.70 while tissue oxygenation was determined by INVOS 5100C. Preoxygenation increased rScO2 (from 65 ± 8% to 72 ± 9%; P < 0.05 and SmO2 (from 75 ± 9% to 78 ± 9%; P < 0.05 and during surgery rScO2 and SmO2 were maintained at the baseline level in most patients. Following anesthesia and tracheal intubation an eventual change in rScO2 correlated to cardiac output and cardiac stroke volume (coefficient of contingence=0.36; P=0.0003 rather to a change in mean arterial pressure and for five patients rScO2 was reduced to below 50%. We conclude that i increased oxygen delivery enhances tissue oxygenation, ii oxygen supports tissue oxygenation but does not prevent a critical reduction in cerebral oxygenation sufficiently, and iii an eventual decrease in tissue oxygenation seems related to a reduction in cardiac output rather than to hypotension.

  7. Expression and relevant research of MGMT and XRCC1 gene in differentgrades of brain glioma and normal brain tissues

    Institute of Scientific and Technical Information of China (English)

    Ya-Fei Zhang

    2015-01-01

    Objective: To explore and analyze expression and relevant research of MGMT and XRCC1 gene in different grades of brain glioma and normal brain tissues. Methods: 52 cases of patients with brain glioma treated in our hospital from December 2013 to December 2014, and 50 cases of normal brain-tissue patients with intracranial hypertension were selected, and proceeding test to the surgical resection of brain tissue of the above patients to determine its MGMT and XRCC1 protein content, sequentially to record the expression of MGMT and XRCC1 of both groups. Grading of tumors to brain glioma after operation was carried out, and the expression of MGMT and XRCC1 gene in brain tissues of different patients was analyzed and compared;finally the contingency tables of X2 test was used to analyze the correlation of XRCC1and MGMT. Results:Positive rate of MGMT expression in normal brain tissue was 2%,while positive rate of MGMT expression in brain glioma was 46.2%,which was obviously higher than that in normal brain tissues (χ2=26.85, P0.05), which had no statistical significance. There were 12 cases of patients whose MGMT protein expression was positive and XRCC1 protein expression was positive; there were 18 cases of patients whose MGMT protein expression was negative and XRCC1 protein expression was negative. Contingency tables of X2 test was used to analyze the correlation of XRCC1 and MGMT, which indicated that the expression of XRCCI and MGMT in brain glioma had no correlation (r=0.9%, P=0.353), relevancy of both was r=0.9%. Conclusions: Positive rate of the expression of MGMT and XRCC1 in brain glioma was obviously higher than that in normal brain tissues, but the distribution of different grades of brain glioma had no obvious difference, and MGMT and XRCC1 expression had no obvious correlation, which needed further research.

  8. Antioxidant Role of Pomegranates on Liver and Brain Tissues of Rats Exposed to an Organophosphorus Insecticide

    International Nuclear Information System (INIS)

    Toxicities of organophosphorus insecticides cause oxidative damage on many organs such as the liver and brain due to generation of reactive oxygen species. Pomegranate is among the richest fruit in poly - phenols. The aim of this study was to compare between the antioxidant strength of pomegranate juice (PJ) and pomegranate molasses (PM) and their effects on alanine transferase (ALT), aspartate aminotransferase (AST), Alkaline phosphatase (ALP) and total protein (TP) in liver and levels of malondialdehyde (MAD), reduced glutathione (GSH) and nitric oxide (NO) in rat liver and brain tissues exposed to 1/10 LD 50 diazinon (DI). Six groups each of 6 male albino rats were used comprising control, DI, PJ, PM, PJ + DI and PM + DI for 15 days. The activities of ALT, AST, and TP concentration in liver have been increased due to treatment of rats with DI. These increases restored to normalcy when rats were supplemented with PJ or PM with DI. The results demonstrate that treatment with DI induced significant increase in MDA and NO concentrations and significant decrease in GSH levels of liver and brain tissues. The administration of PJ or PM along with DI significant decrease in MDA and NO levels and significant increase in GSH level compared to DI-group. The present study suggest that PJ or PM has a potential protective effect as it can elevate antioxidant defense system, lessens induced oxidative dam - ages and protect the brain and liver tissue against DI-induced toxicity. In addition, comaring PJ with PM it was noticed that PJ had higher antioxidant activity as evidenced by increased GSH content and decreased NO level in the liver by greater extend than PM.

  9. In vivo EPR oximetry using an isotopically-substituted nitroxide: Potential for quantitative measurement of tissue oxygen

    Science.gov (United States)

    Weaver, John; Burks, Scott R.; Liu, Ke Jian; Kao, Joseph P. Y.; Rosen, Gerald M.

    2016-10-01

    Variations in brain oxygen (O2) concentration can have profound effects on brain physiology. Thus, the ability to quantitate local O2 concentrations noninvasively in vivo could significantly enhance understanding of several brain pathologies. However, quantitative O2 mapping in the brain has proven difficult. The electron paramagnetic resonance (EPR) spectra of nitroxides are sensitive to molecular O2 and can be used to estimate O2 concentrations in aqueous media. We recently synthesized labile-ester-containing nitroxides, such as 3-acetoxymethoxycarbonyl-2,2,5,5-tetramethyl-1-pyrrolidinyloxyl (nitroxide 4), which accumulate in cerebral tissue after in situ hydrolysis, and thus enable spatial mapping of O2 concentrations in the mouse brain by EPR imaging. In an effort to improve O2 quantitation, we prepared 3-acetoxymethoxycarbonyl-2,2,5,5-tetra(2H3)methyl-1-(3,4,4-2H3,1-15N)pyrrolidinyloxyl (nitroxide 2), which proved to be a more sensitive probe than its normo-isotopic version for quantifying O2 in aqueous solutions of various O2 concentrations. We now demonstrate that this isotopically substituted nitroxide is ∼2-fold more sensitive in vivo than the normo-isotopic nitroxide 4. Moreover, in vitro and in vivo EPR spectral-spatial imaging results with nitroxide 2 demonstrate significant improvement in resolution, reconstruction and spectral response to local O2 concentrations in cerebral tissue. Thus, isotopic-substituted nitroxides, such as 2, are excellent sensors for in vivo O2 quantitation in tissues, such as the brain.

  10. Brain tissue pressure measurements in perinatal and adult rabbits.

    Science.gov (United States)

    Hornig, G W; Lorenzo, A V; Zavala, L M; Welch, K

    1987-12-01

    Brain tissue pressure (BTP) in pre- and post-natal anesthetized rabbits, held in a stereotactic head holder, was measured with a fluid filled 23 gauge open-ended cannula connected distally to a pressure transducer. By advancing the cannula step wise through a hole in the cranium it was possible to sequentially measure pressure from the cranial subarachnoid space, cortex, ventricle and basal ganglia. Separate cannulas and transducers were used to measure CSFP from the cisterna magna and arterial and/or venous pressure. Pressure recordings obtained when the tip of the BTP cannula was located in the cranial subarachnoid space or ventricle exhibited respiratory and blood pressure pulsations equivalent to and in phase with CSF pulsations recorded from the cisterna magna. When the tip was advanced into brain parenchymal sites such pulsations were suppressed or non-detectable unless communication with a CSF compartment had been established inadvertently. Although CSF pressures in the three spinal fluid compartments were equivalent, in most animals BTP was higher than CSFP. However, after momentary venting of the system BTP equilibrated at a pressure below that of CSFP. We speculate that venting of the low compliance system (1.20 x 10(-5) ml/mmHg) relieves the isometric pressure build-up due to insertion of the cannula into brain parenchyma. Under these conditions, and at all ages examined, BTP in the rabbit is consistently lower than CSFP and, as with CSFP, it increases as the animal matures.

  11. Comparative Tissue Stainability of Lawsonia inermis (Henna) and Eosin as Counterstains to Hematoxylin in Brain Tissues.

    Science.gov (United States)

    Alawa, Judith N; Gideon, Gbenga O; Adetiba, Bamidele; Alawa, Clement B

    2015-04-01

    We hyposthesized that henna staining could provide an alternative to eosin when used as a counterstain to hematoxylin for understanding basic neurohistological principles. Therefore, this study was aimed at investigating the suitability of henna as counterstain to hematoxylin for the demonstration of the layer stratification and cellular distribution in the brain tissue. Henna stained nervous tissue by reacting with the basic elements in proteins via its amino groups. It stained the neuropil and connective tissue membranes brown and effectively outlined the perikarya of neurons with no visible nuclei demonstrating that it is an acidic dye. Henna as a counterstain to hematoxylin demonstrated reliability as a new neurohistological stain. It facilitated identification of cortical layer stratification and cellular distribution in brain tissue sections from Wistar rats. This was comparable to standard hematoxylin and eosin staining as morphological and morphometrical analyses of stained cells did not show significant differences in size or number. This study presents a method for staining with henna and demonstrates that although henna and eosin belong to different dye groups (anthraquinone and xanthenes, respectively) based on their chromophores, they share similar staining techniques and thus could be used interchangeably in neurohistology.

  12. 大鼠实验性脑出血后高血糖对血肿周围脑组织乳酸与氧自由基的影响%The effect of post-ICH hyperglycemia on the level of lactic acid and oxygen free radicals in brain tissue around hemotuma

    Institute of Scientific and Technical Information of China (English)

    王小蓉; 徐斌; 李小刚

    2011-01-01

    Objective To observe the effect of post-ICH hyperglycemia on the level of lactic acid and oxygen free radicats in brain tissue around hemotoma and to explore the relative mechanism. Methods The intracerebral hemorrhage (ICH) rat model was established by autologous blood injection, SD rats were randomly divided into sham operation group (SO), pure cerebral hemorrhage (PCH), post-ICH hyperglycemia group by 2g/kg injection of glucose (2-IG), and 4g/kg injection glucose (4-IG). We observed 0, 1, 6 h blood glucose and 0,1,3, 7,10, 14 d perihematoma LA, SOD, MDA content Results 1, 6 h blood glucose values was significantly higher (P<0. 05) in 2-IG group and 4-IG group than in SO group. LA and MDA of rat brain tissue surrounding hematoma were significantly higher (F<0.05) and SOD was lower (P<0.05) in 2-IG and 4-IG group than in PCH group. Conclusions Hyperglycemia after cerebral hemorrhage leads to lactate and MDA accumulation and to the decreased SOD, possibly through free radical chain reaction.%观察大鼠脑出血(ICH)后高血糖对血肿周围脑组织乳酸(LA)和氧自由基的影响,探讨ICH后高血糖加重脑损伤的可能机制.采用自体血注入法建立ICH模型,将SD大鼠随机分成假手术组(SO)、单纯脑出血组(PCH)、ICH后高血糖组,ICH后高血糖组又分为2g/kg(2-IG)和4g/kg(4-IG)注射葡萄糖组.观察各组大鼠术前和术后1、6h血糖变化;测定各组大鼠术后1、3、7、10、14d血肿周围脑组织LA、超氧化物歧化酶(SOD)、丙二醛(MDA)的含量变化. 结果与SO组比较,2-IG组和4-IG组术后1、6h血糖明显升高(P<0.05);与PCH组比较,2-IG组和4-IG组大鼠血肿周围脑组织LA和MDA含量明显升高(P<0.05),SOD含量明显降低(P<0.05). 结论 脑出血后高血糖导致能量代谢障碍,LA蓄积甚至中毒,可能通过氧自由基连锁反应加重脑损伤.

  13. Monitoring tissue oxygen availability with near infrared spectroscopy (NIRS) in health and disease

    DEFF Research Database (Denmark)

    Boushel, Robert Christopher; Langberg, H; Olesen, J;

    2001-01-01

    Near infrared spectroscopy (NIRS) is becoming a widely used research instrument to measure tissue oxygen (O2) status non-invasively. Continuous-wave spectrometers are the most commonly used devices, which provide semi-quantitative changes in oxygenated and deoxygenated hemoglobin in small blood v...... patterns in very localized regions of tissue and may be fruitful in the study of occupational syndromes and a variety of diseases....

  14. Experimental in-vivo study of laser-tissue interaction on the brain: influence of gaseous environment

    Science.gov (United States)

    Chavantes, Maria C.; Zamorano, Lucia J.; Vinas, Federico; Dujovny, Manuel; Dragovic, Ljubisa

    1990-06-01

    The present study attempted to assess the in vivo effects of Nd-YAG laser irradiation in different gaseous environments on liver and brain. Such an investigation is critical for determining the extent of injury under such conditions for improving further clinical applications. We intended to define the influence on laser-tissue interaction of Room Air, 30% Oxygen, Helium, and Nitrogen. The anesthetized rats were placed in a special chamber and kept breathtng via a tracheostomy tube to the outside, and craniotomy or laparotomy was performed. Nd-YAG laser fiber was directed with a fixed distance at the exposed brain/liver. The staining drug for brain study was 2,3,5 triphenyltetrazolium chloride, which was injected into the aorta before sacrificing the animals. The 44 rats studied were divided into: liver and brain groups. The resulting lesions were photographed macroscopically. In the liver group, statistical analysis showed that laser-liver tissue interaction in helium and nitrogen created a well defined and less hemorrhagic lesions. Macroscopically, in the brain group, we found that the target zones were well delineated with Nitrogen concentration. Moreover, we observed smaller lesions and more sharply defined areas with Helium concentration. In Room Air and Oxygen concentrations, more carbonized and bloodish lesions were found. Laser-tissue interaction in Helium and Nitrogen environments produces more sharply defined lesions with less involvement of the sorrounding tissue, less hemorrhagic lesions to the target, and reduce smoke production. This effect may be of benefit in clinical application of Nd YAG laser, where a more specific target-laser interaction could be achieved avoiding undesired complications due to penetration on the surrounding healthy tissue.

  15. Implementing oxygen control in chip-based cell and tissue culture systems

    NARCIS (Netherlands)

    Oomen, Pieter; Skolimowski, Maciej; Verpoorte, Elisabeth

    2016-01-01

    Oxygen is essential in the energy metabolism of cells, as well as being an important regulatory parameter influencing cell differentiation and function. Interest in precise oxygen control for in vitro cultures of tissues and cells continues to grow, especially with the emergence of the organ-on-a-ch

  16. Monitoring tissue oxygen availability with near infrared spectroscopy (NIRS) in health and disease

    DEFF Research Database (Denmark)

    Boushel, R; Langberg, Henning; Olesen, J;

    2001-01-01

    Near infrared spectroscopy (NIRS) is becoming a widely used research instrument to measure tissue oxygen (O2) status non-invasively. Continuous-wave spectrometers are the most commonly used devices, which provide semi-quantitative changes in oxygenated and deoxygenated hemoglobin in small blood...

  17. Magnetic resonance brain tissue segmentation based on sparse representations

    Science.gov (United States)

    Rueda, Andrea

    2015-12-01

    Segmentation or delineation of specific organs and structures in medical images is an important task in the clinical diagnosis and treatment, since it allows to characterize pathologies through imaging measures (biomarkers). In brain imaging, segmentation of main tissues or specific structures is challenging, due to the anatomic variability and complexity, and the presence of image artifacts (noise, intensity inhomogeneities, partial volume effect). In this paper, an automatic segmentation strategy is proposed, based on sparse representations and coupled dictionaries. Image intensity patterns are singly related to tissue labels at the level of small patches, gathering this information in coupled intensity/segmentation dictionaries. This dictionaries are used within a sparse representation framework to find the projection of a new intensity image onto the intensity dictionary, and the same projection can be used with the segmentation dictionary to estimate the corresponding segmentation. Preliminary results obtained with two publicly available datasets suggest that the proposal is capable of estimating adequate segmentations for gray matter (GM) and white matter (WM) tissues, with an average overlapping of 0:79 for GM and 0:71 for WM (with respect to original segmentations).

  18. LOCALISED MUSCLE TISSUE OXYGENATION DURING DYNAMIC EXERCISE WITH WHOLE BODY VIBRATION

    Directory of Open Access Journals (Sweden)

    Daniel Robbins

    2012-06-01

    Full Text Available Despite increasing use of whole body vibration during exercise an understanding of the exact role of vibration and the supporting physiological mechanisms is still limited. An important aspect of exercise analysis is the utilisation of oxygen, however, there have been limited studies considering tissue oxygenation parameters, particularly during dynamic whole body vibration (WBV exercise. The aim of this study was to determine the effect of adding WBV during heel raise exercises and assessing changes in tissue oxygenation parameters of the lateral gastrocnemius using Near Infra Red Spectroscopy (NIRS. Twenty healthy subjects completed ten alternating sets of 15 heel raises (vibration vs. no vibration. Synchronous oxygenation and motion data were captured prior to exercise to determine baseline levels, for the duration of the exercise and 20 sec post exercise for the recovery period. Both vibration and no vibration conditions elicited a characteristic increase in deoxyhaemoglobin and decreases in oxyhaemoglobin, total haemoglobin, tissue oxygenation index and normalised tissue haemoglobin index which are indicative of local tissue hypoxia. However, the addition of vibration elicited significantly lower (p < 0. 001 depletions in oxyhaemoglobin, total haemoglobin, normalised tissue haemoglobin index but no significant differences in deoxyhaemoglobin. These findings suggest that addition of vibration to exercise does not increase the cost of the exercise for the lateral gastrocnemius muscle, but does decrease the reduction in local muscle oxygenation parameters, potentially resulting from increased blood flow to the calf or a vasospastic response in the feet. However, further studies are needed to establish the mechanisms underlying these findings

  19. Eigenspectra optoacoustic tomography achieves quantitative blood oxygenation imaging deep in tissues

    CERN Document Server

    Tzoumas, Stratis; Olefir, Ivan; Stangl, Stefan; Symvoulidis, Panagiotis; Glasl, Sarah; Bayer, Christine; Multhoff, Gabriele; Ntziachristos, Vasilis

    2015-01-01

    Light propagating in tissue attains a spectrum that varies with location due to wavelength-dependent fluence attenuation by tissue optical properties, an effect that causes spectral corruption. Predictions of the spectral variations of light fluence in tissue are challenging since the spatial distribution of optical properties in tissue cannot be resolved in high resolution or with high accuracy by current methods. Spectral corruption has fundamentally limited the quantification accuracy of optical and optoacoustic methods and impeded the long sought-after goal of imaging blood oxygen saturation (sO2) deep in tissues; a critical but still unattainable target for the assessment of oxygenation in physiological processes and disease. We discover a new principle underlying light fluence in tissues, which describes the wavelength dependence of light fluence as an affine function of a few reference base spectra, independently of the specific distribution of tissue optical properties. This finding enables the introd...

  20. Evaluation of hyperbaric oxygen treatment of neuropsychiatric disorders following traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    SHI Xiao-yan; TANG Zhong-quan; SUN Da; HE Xiao-jun

    2006-01-01

    Background Improvement of clinical symptoms following hyperbaric oxygen (HBO) treatment of neuropsychiatric disorders arising from traumatic brain injury was proved by our previous study. This study was aim to obtain the evidence of other changes.Methods Three hundred and ten patients with neuropsychiatric disorders arising from traumatic brain injury were treated twice with hyperbaric oxygen. Cerebral single photon emissions computed tomography (SPECT)images and computed tomography scans (CT) before and after hyperbaric oxygen treatment, were compared.Results Before treatment, the proportion of abnormal cerebral changes detected by SPECT was 81.3% but only 15.2% by CT. After HBO treatment, 70.3% of SPECT scans showed no abnormalities and these patients were clinically improved. Treatment improved regional cerebral blood flow.Conclusion SPECT was much more sensitive than CT in the diagnosis of neuropsychiatric disorders following hyperbaric oxygen treatment of neuropsychiatric disorders arising from traumatic brain injury.

  1. Effect of oxygen breathing on micro oxygen bubbles in nitrogen-depleted rat adipose tissue at sea level and 25 kPa altitude exposures

    DEFF Research Database (Denmark)

    Randsoe, Thomas; Hyldegaard, Ole

    2012-01-01

    The standard treatment of altitude decompression sickness (aDCS) caused by nitrogen bubble formation is oxygen breathing and recompression. However, micro air bubbles (containing 79% nitrogen), injected into adipose tissue, grow and stabilize at 25 kPa regardless of continued oxygen breathing...... and the tissue nitrogen pressure. To quantify the contribution of oxygen to bubble growth at altitude, micro oxygen bubbles (containing 0% nitrogen) were injected into the adipose tissue of rats depleted from nitrogen by means of preoxygenation (fraction of inspired oxygen = 1.0; 100%) and the bubbles studied...... prebreathing at 101.3 kPa (sea level). Micro oxygen bubbles of 500-800 nl were then injected into the exposed abdominal adipose tissue. The oxygen bubbles were studied for up to 3.5 h during continued oxygen breathing at either 101.3 or 25 kPa ambient pressures. At 101.3 kPa, all bubbles shrank consistently...

  2. Erythropoietin Modulates Autophagy Signaling in the Developing Rat Brain in an In Vivo Model of Oxygen-Toxicity

    Directory of Open Access Journals (Sweden)

    Marco Sifringer

    2012-10-01

    Full Text Available Autophagy is a self-degradative process that involves turnover and recycling of cytoplasmic components in healthy and diseased tissue. Autophagy has been shown to be protective at the early stages of programmed cell death but it can also promote apoptosis under certain conditions. Earlier we demonstrated that oxygen contributes to the pathogenesis of neonatal brain damage, which can be ameliorated by intervention with recombinant human erythropoietin (rhEpo. Extrinsic- and intrinsic apoptotic pathways are involved in oxygen induced neurotoxicity but the role of autophagy in this model is unclear. We analyzed the expression of autophagy activity markers in the immature rodent brain after exposure to elevated oxygen concentrations. We observed a hyperoxia-exposure dependent regulation of autophagy-related gene (Atg proteins Atg3, 5, 12, Beclin-1, microtubule-associated protein 1 light chain 3 (LC3, LC3A-II, and LC3B-II which are all key autophagy activity proteins. Interestingly, a single injection with rhEpo at the onset of hyperoxia counteracted these oxygen-mediated effects. Our results indicate that rhEpo generates its protective effect by modifying the key autophagy activity proteins.

  3. Brain-derived neurotrophic factor expression is higher in brain tissue from patients with refractory epilepsy than in normal controls

    Institute of Scientific and Technical Information of China (English)

    Yudan Lv; Jiqing Qiu; Zan Wang; Li Cui; Hongmei Meng; Weihong Lin

    2011-01-01

    The role of the brain-derived neurotrophic factor in epilepsy remains controversial. The present study utilized light and electron microscopy to investigate pathological and ultrastructural changes in brain tissue obtained from the seizure foci of 24 patients with temporal epilepsy. We found that epileptic tissue showed neuronal degeneration, glial cell proliferation, nuclear vacuolization, and neural cell tropism. Immunoelectron microscopy and immunohistochemistry showed that brain-derived neurotrophic factor was expressed at significantly higher levels in patients with refractory temporal epilepsy compared with normal controls, demonstrating that the pathological changes within seizure foci in patients with refractory epilepsy are associated with brain-derived neurotrophic factor expression alterations.

  4. Regulation of ongoing DNA synthesis in normal and neoplastic brain tissue

    OpenAIRE

    Yakisich, Juan Sebastián

    2005-01-01

    The treatment of human brain tumour is challenging in part due to the blood brain barrier and in part due to the specific biology of brain tumours that confer resistance to chemotherapy. For instance, the 5 years survival rate for patients carrying intracranial glioblastoma multiforme has remained at 4-5 % for the last 30 years. The knowledge of the brain tumour biology as well as the biology of the normal brain tissue would help to design new therapeutic strategies and to d...

  5. Comparison Between Cerebral Tissue Oxygen Tension and Energy Metabolism in Experimental Subdural Hematoma

    DEFF Research Database (Denmark)

    Nielsen, Troels Halfeld; Engell, Susanne I; Johnsen, Rikke Aagaard;

    2011-01-01

    . Intracranial pressure (ICP) was monitored in the "good-side." RESULTS: ICP, cerebral perfusion pressure (CPP), PbtO(2), glucose, lactate, pyruvate, lactate-pyruvate ratio (LP ratio), glutamate, and glycerol were recorded at baseline (60 min) and post trauma (360 min). After the creation of the ASDH, PbtO(2......BACKGROUND: An experimental swine model (n = 7) simulating an acute subdural hematoma (ASDH) was employed (1) to explore the relation between the brain tissue oxygenation (PbtO(2)) and the regional cerebral energy metabolism as obtained by microdialysis, and (2) to define the lowest level of PbtO(2......) compatible with intact energy metabolism. METHODS: ASDH was produced by infusion of 7 ml of autologous blood (infusion rate 0.5 ml/min) by a catheter placed subdurally. PbtO(2) and microdialysis probes were placed symmetrically in the injured ("bad-side") and non-injured ("good-side") hemispheres...

  6. Quasi-simultaneous multimodal imaging of cutaneous tissue oxygenation and perfusion

    Science.gov (United States)

    Ren, Wenqi; Gan, Qi; Wu, Qiang; Zhang, Shiwu; Xu, Ronald

    2015-12-01

    Simultaneous and quantitative assessment of multiple tissue parameters may facilitate more effective diagnosis and therapy in many clinical applications, such as wound healing. However, existing wound assessment methods are typically subjective and qualitative, with the need for sequential data acquisition and coregistration between modalities, and lack of reliable standards for performance evaluation or calibration. To overcome these limitations, we developed a multimodal imaging system for quasi-simultaneous assessment of cutaneous tissue oxygenation and perfusion in a quantitative and noninvasive fashion. The system integrated multispectral and laser speckle imaging technologies into one experimental setup. Tissue oxygenation and perfusion were reconstructed by advanced algorithms. The accuracy and reliability of the imaging system were quantitatively validated in calibration experiments and a tissue-simulating phantom test. The experimental results were compared with a commercial oxygenation and perfusion monitor. Dynamic detection of cutaneous tissue oxygenation and perfusion was also demonstrated in vivo by a postocclusion reactive hyperemia procedure in a human subject and a wound healing process in a wounded mouse model. Our in vivo experiments not only validated the performance of the multimodal imaging system for cutaneous tissue oxygenation and perfusion imaging but also demonstrated its technical potential for wound healing assessment in clinical practice.

  7. Influence of hyperbaric oxygen on the differentiation of hypoxic/ischemic brain-derived neural stem cells

    Institute of Scientific and Technical Information of China (English)

    Zhengrong Peng; Sue Wang; Pingtian Xiao

    2009-01-01

    BACKGROUND: It has been previously shown that hyperbaric oxygen may promote proliferation of neural stem cells and reduce death of endogenous neural stem cells (NSCs).OBJECTIVE: To explore the effects of hyperbaric oxygen on the differentiation of hypoxic/ischemic brain-derived NSCs into neuron-like cells and compare with high-concentration oxygen and high pressure.DESIGN, TIME AND SETTING: An in vitro contrast study, performed at Laboratory of Neurology,Central South University between January and May 2006.MATERIALS: A hyperbaric oxygen chamber (YLC 0.5/1A) was provided by Wuhan Shipping Design Research Institute; mouse anti-rat microtubute-associated protein 2 monoclonal antibody by Jingmei Company, Beijing; mouse anti-rat glial fibrillary acidic protein monoclonal antibody by Neo Markers,USA; mouse anti-rat galactocerebroside monoclonal antibody by Santa Cruz Biotechnology Inc.,USA; and goat anti-mouse fluorescein isothiocyanate-labeled secondary antibody by Wuhan Boster Bioengineering Co., Ltd., China.METHODS: Brain-derived NSCs isolated from brain tissues of neonatal Sprague Dawiey rats werecloned and passaged, and assigned into five groups: normal control, model, high-concentration oxygen, high pressure, and hyperbaric oxygen groups. Cells in the four groups, excluding the normal control group, were incubated in serum-containing DMEM/F12 culture medium. Hypoxic/ischemic models of NSCs were established in an incubator comprising 93% N2, 5% CO2, and 2% O2.Thereafter, cells were continuously cultured as follows: compressed air (0.2 MPa, 1 hour, once a day)in the high pressure group, compressed air+a minimum of 80% O2 in the hyperbaric oxygen group,and a minimum of 80% O2 in the high-concentration oxygen group. Cells in the normal control and model groups were cultured as normal.MAIN OUTCOME MEASURES: At day 7 after culture, glial fibrillary acidic protein,microtubule-associated protein 2, and galactocerebroside immunofluorescence staining were examined to

  8. Mechanism of brain and spinal cord tissue injury following decompression sickness in experimental rabbits and the effect of hyperbaric oxygen%减压病兔脑和脊髓组织损伤机制及高压氧疗效

    Institute of Scientific and Technical Information of China (English)

    王翠翠; 刘晓红; 毛蕊琪; 曹永成; 毕利泉; 耿明

    2014-01-01

    Objective To investigate the mechanism of brain and spinal cord injury in experimental rabbits with decompression sickness (DCS) and the effect of hyperbaric oxygen (HBO).Methods Twentyeight adult male healthy New Zealand rabbits were randomly divided into 4 groups:the normal control group,the DCS group,the safe decompression group and the HBO group,each consisting of 7 animals.The rabbits in the DCS group were compressed with air in 5 minutes to a pressure 0.8 MPa and maintained at the said pressure for 60 min,and then were decompressed to normal pressure within 5 min.The animals in the HBO group underwent the same compression and decompression procedures,as the animals in the DCS group,but were immediately put into the hyperbaric chamber to receive HBO therapy.The safe decompression group was compressed and decompressed with the profile of the Chinese Navy Diving Decompression Tables.Changes in pathological morphology and apoptosis of brain and spinal cord tissue cells in the thoracic and lumbar segments were observed with light microscopy and terminal deoxynucleotidyl transferase-mediated DUTP nick end labeling (TUNEL) method.Results For the animals in the DCS group,cavity in the white matter of the spinal cord and proliferation of gliocytes around the damaged tissue could obviously be observed.TUNEL results showed that more positive apoptotic cells were detected in the DCS group (28.29 ± 2.56)/HP,as compared with those of the normal control group (0.57 ± 0.54)/HP,the safe decompression group (2.29 ± 1.11)/HP and the HBO group (3.71 ± 1.11)/HP,with statistical significance (P < 0.05).More positive apoptotic cells were also seen in the HBO group (3.71 ± 1.1 1)/HP,as compared with those of the normal control group (P <0.05),but were significantly less,as compared with those of the DCS group (P < 0.05),also with statistical significance (P < 0.05).Slightly more positive apoptotic cells were detected in the animals of the HBO group,when compared with

  9. Oxygenation and Blood Volume Periodic Waveforms in the Brain

    CERN Document Server

    Gersten, Alexander; Raz, Amir

    2011-01-01

    Results of an experiment are presented whose aim is to explore the relationship between respiration and cerebral oxygenation. Measurements of end tidal CO2 (EtCO2) were taken simultaneously with cerebral oxygen saturation (rSO2) using the INVOS Cerebral Oximeter of Somanetics. Due to the device limitations we could explore only subjects who could perform with a breathing rate of around 2/min or less. Six subjects were used who were experienced in yoga breathing techniques. They performed an identical periodic breathing exercise including periodicity of about 2/min. The results of all six subjects clearly show a periodic change of cerebral oxygenation with the same period as the breathing exercises. Similar periodic changes in blood volume index were observed as well.

  10. Oxygenation and Blood Volume Periodic Waveforms in the Brain

    OpenAIRE

    Gersten, Alexander; Heimer, Dov; Raz, Amir

    2011-01-01

    Results of an experiment are presented whose aim is to explore the relationship between respiration and cerebral oxygenation. Measurements of end tidal CO2 (EtCO2) were taken simultaneously with cerebral oxygen saturation (rSO2) using the INVOS Cerebral Oximeter of Somanetics. Due to the device limitations we could explore only subjects who could perform with a breathing rate of around 2/min or less. Six subjects were used who were experienced in yoga breathing techniques. They performed an i...

  11. Continuous tissue oxygen tension measurement as a monitor of free-flap viability.

    Science.gov (United States)

    Hirigoyen, M B; Blackwell, K E; Zhang, W X; Silver, L; Weinberg, H; Urken, M L

    1997-03-01

    Early recognition of vascular compromise within microvascular free-tissue transfers is essential if reexploration is to prove successful. Tissue oxygen tension is increasingly recognized to be a sensitive and reliable index of tissue perfusion, and preliminary studies suggest that it may be of value in the assessment of free-flap viability. We describe our investigation into the application of an implantable microcatheter oxygen sensor in the monitoring of free flaps used in head and neck and extremity reconstruction. In a preliminary study using the rabbit model, we sought to evaluate the response of oxygen tension as an index of tissue perfusion in myocutaneous (n = 20) and osteomyocutaneous flaps (n = 5) under conditions of arterial and venous occlusion. A clinical study was then undertaken to evaluate the role of this method in the monitoring of surface and buried free flaps. In 30 heterogeneous free-tissue transfers, sensors placed intraoperatively were used to provide continuous information about flap oxygen tension (mean monitoring period 3.2 +/- 0.8 days). The data generated were correlated with changes in clinical parameters and routine flap observations. Results for experimental and clinical data have confirmed the efficacy of continuous tissue oxygen measurements using this device as a method that provides an objective, recordable index of free-tissue transfer viability in a variety of circumstances and vascular events. Tissue oxygen tension is a suitable index by which to evaluate flap viability with the probe placed in muscle or bone but is unreliable when used for the monitoring of revascularized cutaneous flaps. PMID:9047197

  12. Alteration of Brain Oxygenation During "Piggy Back" Liver Transplantation

    Science.gov (United States)

    Panzera, Piercarmine; Greco, Luigi; Carravetta, Giuseppe; Gentile, Antonella; Catalano, Giorgio; Cicco, Giuseppe; Memeo, Vincenzo

    Relevant changes in cerebral circulation occur during "Piggy Back" liver transplantation. Particularly at the washout-reperfusion time the cerebral perfusion suddenly changes from its lowest to its highest values. Further investigation is required to evaluate whether patients with the greatest change in cerebral oxygenation at this time point will suffer neurological complications after transplantation.

  13. Visceral adipose tissue inflammation is associated with age-related brain changes and ischemic brain damage in aged mice.

    Science.gov (United States)

    Shin, Jin A; Jeong, Sae Im; Kim, Minsuk; Yoon, Joo Chun; Kim, Hee-Sun; Park, Eun-Mi

    2015-11-01

    Visceral adipose tissue is accumulated with aging. An increase in visceral fat accompanied by low-grade inflammation is associated with several adult-onset diseases. However, the effects of visceral adipose tissue inflammation on the normal and ischemic brains of aged are not clearly defined. To examine the role of visceral adipose tissue inflammation, we evaluated inflammatory cytokines in the serum, visceral adipose tissue, and brain as well as blood-brain barrier (BBB) permeability in aged male mice (20 months) underwent sham or visceral fat removal surgery compared with the young mice (2.5 months). Additionally, ischemic brain injury was compared in young and aged mice with sham and visceral fat removal surgery. Interleukin (IL)-1β, IL-6, and tumor necrosis factor-α levels in examined organs were increased in aged mice compared with the young mice, and these levels were reduced in the mice with visceral fat removal. Increased BBB permeability with reduced expression of tight junction proteins in aged sham mice were also decreased in mice with visceral fat removal. After focal ischemic injury, aged mice with visceral fat removal showed a reduction in infarct volumes, BBB permeability, and levels of proinflammatory cytokines in the ischemic brain compared with sham mice, although the neurological outcomes were not significantly improved. In addition, further upregulated visceral adipose tissue inflammation in response to ischemic brain injury was attenuated in mice with visceral fat removal. These results suggest that visceral adipose tissue inflammation is associated with age-related changes in the brain and contributes to the ischemic brain damage in the aged mice. We suggest that visceral adiposity should be considered as a factor affecting brain health and ischemic brain damage in the aged population. PMID:26184082

  14. Visceral adipose tissue inflammation is associated with age-related brain changes and ischemic brain damage in aged mice.

    Science.gov (United States)

    Shin, Jin A; Jeong, Sae Im; Kim, Minsuk; Yoon, Joo Chun; Kim, Hee-Sun; Park, Eun-Mi

    2015-11-01

    Visceral adipose tissue is accumulated with aging. An increase in visceral fat accompanied by low-grade inflammation is associated with several adult-onset diseases. However, the effects of visceral adipose tissue inflammation on the normal and ischemic brains of aged are not clearly defined. To examine the role of visceral adipose tissue inflammation, we evaluated inflammatory cytokines in the serum, visceral adipose tissue, and brain as well as blood-brain barrier (BBB) permeability in aged male mice (20 months) underwent sham or visceral fat removal surgery compared with the young mice (2.5 months). Additionally, ischemic brain injury was compared in young and aged mice with sham and visceral fat removal surgery. Interleukin (IL)-1β, IL-6, and tumor necrosis factor-α levels in examined organs were increased in aged mice compared with the young mice, and these levels were reduced in the mice with visceral fat removal. Increased BBB permeability with reduced expression of tight junction proteins in aged sham mice were also decreased in mice with visceral fat removal. After focal ischemic injury, aged mice with visceral fat removal showed a reduction in infarct volumes, BBB permeability, and levels of proinflammatory cytokines in the ischemic brain compared with sham mice, although the neurological outcomes were not significantly improved. In addition, further upregulated visceral adipose tissue inflammation in response to ischemic brain injury was attenuated in mice with visceral fat removal. These results suggest that visceral adipose tissue inflammation is associated with age-related changes in the brain and contributes to the ischemic brain damage in the aged mice. We suggest that visceral adiposity should be considered as a factor affecting brain health and ischemic brain damage in the aged population.

  15. Glasgow Coma Scale, brain electric activity mapping and Glasgow Outcome Scale after hyperbaric oxygen treatment of severe brain injury

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To study the effect of hyperbaric oxygen (HBO) treatment of severe brain injury.Methods: Fifty-five patients were divided into a treatment group (n = 35 receiving HBO therapy ) and a control group (n = 20 receiving dehydrating, cortical steroid and antibiotic therapy) to observe the alteration of clinic GCS (Glasgow Coma Scale), brain electric activity mapping (BEAM), prognosis and GOS (Glasgow Outcome Scale) before and after hyperbaric oxygen treatment.Results: In the treatment group GCS, BEAM and GOS were improved obviously after 3 courses of treatment,GCS increased from 5.1 to 14.6 ( P < 0.01-0.001 ), the BEAM abnormal rate reduced from 94.3% to 38% (P <0.01-0.001 ), the GOS good-mild disability rate was 83.7%, and the middle-severe disability rate was 26.3%compared with the control group. There was a statistic significant difference between the two groups (P < 0.01-0.001).Conclusions: Hyperbaric oxygen treatment could improve obviously GCS, BEAM and GOS of severe brain injury patients, and effectively reduce the mortality and morbidity. It is an effective method to treat severe brain injury. two g

  16. Effects of anesthetic agents on brain blood oxygenation level revealed with ultra-high field MRI.

    Directory of Open Access Journals (Sweden)

    Luisa Ciobanu

    Full Text Available During general anesthesia it is crucial to control systemic hemodynamics and oxygenation levels. However, anesthetic agents can affect cerebral hemodynamics and metabolism in a drug-dependent manner, while systemic hemodynamics is stable. Brain-wide monitoring of this effect remains highly challenging. Because T(2*-weighted imaging at ultra-high magnetic field strengths benefits from a dramatic increase in contrast to noise ratio, we hypothesized that it could monitor anesthesia effects on brain blood oxygenation. We scanned rat brains at 7T and 17.2T under general anesthesia using different anesthetics (isoflurane, ketamine-xylazine, medetomidine. We showed that the brain/vessels contrast in T(2*-weighted images at 17.2T varied directly according to the applied pharmacological anesthetic agent, a phenomenon that was visible, but to a much smaller extent at 7T. This variation is in agreement with the mechanism of action of these agents. These data demonstrate that preclinical ultra-high field MRI can monitor the effects of a given drug on brain blood oxygenation level in the absence of systemic blood oxygenation changes and of any neural stimulation.

  17. Cerebral tissue oxygenation index and superior vena cava blood flow in the very low birth weight infant.

    LENUS (Irish Health Repository)

    Moran, M

    2012-02-01

    BACKGROUND: Superior vena cava (SVC) flow assesses blood flow from the upper body, including the brain. Near infrared spectroscopy (NIRS) provides information on brain perfusion and oxygenation. AIM: To assess the relationship between cerebral tissue oxygenation index (cTOI) and cardiac output measures in the very low birth weight (VLBW) infant in the first day of life. METHODS: A prospective observational cohort study. Neonates with birth weight less than 1500 g (VLBW) were eligible for enrollment. Newborns with congenital heart disease, major congenital malformations and greater than Papile grade1 Intraventricular Haemorrhage on day 1 of life were excluded. Echocardiographic evaluation of SVC flow was performed in the first 24 h of life. Low SVC flow states were defined as a flow less than 40 mL\\/kg\\/min. cTOI was measured using NIRO 200 Hamamatsu. RESULTS: Twenty-seven VLBW neonates had both echocardiography and NIRS performed. The median (range) gestation was 29\\/40 (25 + 3 to 31 + 5 weeks) and median birth weight was 1.2 kg (0.57-1.48 kg). The mean (SD) TOI was 68.1 (7.9)%. The mean (SD) SVC flow was 70.36(39.5) mLs\\/kg\\/min. The correlation coefficient of cerebral tissue oxygenation and SVC flow was r = 0.53, p-value 0.005. There was a poor correlation between right and left ventricular output and cTOI which is not surprising considering the influence of intra- and extracardiac shunts. CONCLUSION: There is a positive relationship between cerebral TOI values and SVC flow in the very low birth infant on day one of life.

  18. Frequency-Dependent Viscoelastic Parameters of Mouse Brain Tissue Estimated by MR Elastography

    OpenAIRE

    Clayton, E. H.; Garbow, J. R.; Bayly, P.V.

    2011-01-01

    Viscoelastic properties of mouse brain tissue were estimated non-invasively, in vivo, using magnetic resonance elastography (MRE) at 4.7 T to measure the dispersive properties of induced shear waves. Key features of this study include: (i) the development and application of a novel MR-compatible actuation system which transmits vibratory motion into the brain through an incisor bar; and (ii) the investigation of the mechanical properties of brain tissue over a 1200 Hz bandwidth from 600 Hz –1...

  19. Brain Extraction and Fuzzy Tissue Segmentation in Cerebral 2D T1-Weigthed Magnetic Resonance Images

    OpenAIRE

    Bouchaib Cherradi; Omar Bouattane; Mohamed Youssfi; Abdelhadi Raihani

    2011-01-01

    In medical imaging, accurate segmentation of brain MR images is of interest for many brain manipulations. In this paper, we present a method for brain Extraction and tissues classification. An application of this method to the segmentation of simulated MRI cerebral images in three clusters will be made. The studied method is composed with different stages, first Brain Extraction from T1-weighted 2D MRI slices (TMBE) is performed as pre-processing procedure, then Histogram based centroids init...

  20. Measurements of tissue oxygen tension in vascularised jejunal autografts in pigs.

    Science.gov (United States)

    Nielsen, I M; Riis, A; Jahn, H; Gottrup, F

    1995-12-01

    Tissue oxygen measurements were evaluated as a monitor of the jejunal flap in seven female landrace pigs. A small polarographic sensor (diameter 0.55 mm) was used in which interstitial tissue oxygen tension was measured continuously in a jejunal flap and a muscle flap (rectus abdominis) during arterial and venous occlusion. Mean (SEM) tissue oxygen tension in the two types of flap were 44(9) mmHg (jejunal flap) and 47(8) mmHg (rectus flap). After arterial occlusion for 30 minutes the values dropped to 17(4) mmHg for the jejunal flap and 12(2) mmHg for the muscle flap. The decline became significant after five minutes. During venous occlusion (30 minutes) the values fell to 20(4) mmHg and 14(1) mmHg. The arterial occlusion was undetectable by the naked eye, but the enteric tissue after venous occlusion became severely congested and blue-black in colour. The condition returned to normal after release of the clamp. We conclude that direct measurement of tissue oxygen tension in a jejunal flap is a reliable method of detecting impaired perfusion. This method may in the future be used to monitor vascularised jejunal autografts. PMID:8771255

  1. Eigenspectra optoacoustic tomography achieves quantitative blood oxygenation imaging deep in tissues

    Science.gov (United States)

    Tzoumas, Stratis; Nunes, Antonio; Olefir, Ivan; Stangl, Stefan; Symvoulidis, Panagiotis; Glasl, Sarah; Bayer, Christine; Multhoff, Gabriele; Ntziachristos, Vasilis

    2016-06-01

    Light propagating in tissue attains a spectrum that varies with location due to wavelength-dependent fluence attenuation, an effect that causes spectral corruption. Spectral corruption has limited the quantification accuracy of optical and optoacoustic spectroscopic methods, and impeded the goal of imaging blood oxygen saturation (sO2) deep in tissues; a critical goal for the assessment of oxygenation in physiological processes and disease. Here we describe light fluence in the spectral domain and introduce eigenspectra multispectral optoacoustic tomography (eMSOT) to account for wavelength-dependent light attenuation, and estimate blood sO2 within deep tissue. We validate eMSOT in simulations, phantoms and animal measurements and spatially resolve sO2 in muscle and tumours, validating our measurements with histology data. eMSOT shows substantial sO2 accuracy enhancement over previous optoacoustic methods, potentially serving as a valuable tool for imaging tissue pathophysiology.

  2. Eigenspectra optoacoustic tomography achieves quantitative blood oxygenation imaging deep in tissues

    Science.gov (United States)

    Tzoumas, Stratis; Nunes, Antonio; Olefir, Ivan; Stangl, Stefan; Symvoulidis, Panagiotis; Glasl, Sarah; Bayer, Christine; Multhoff, Gabriele; Ntziachristos, Vasilis

    2016-01-01

    Light propagating in tissue attains a spectrum that varies with location due to wavelength-dependent fluence attenuation, an effect that causes spectral corruption. Spectral corruption has limited the quantification accuracy of optical and optoacoustic spectroscopic methods, and impeded the goal of imaging blood oxygen saturation (sO2) deep in tissues; a critical goal for the assessment of oxygenation in physiological processes and disease. Here we describe light fluence in the spectral domain and introduce eigenspectra multispectral optoacoustic tomography (eMSOT) to account for wavelength-dependent light attenuation, and estimate blood sO2 within deep tissue. We validate eMSOT in simulations, phantoms and animal measurements and spatially resolve sO2 in muscle and tumours, validating our measurements with histology data. eMSOT shows substantial sO2 accuracy enhancement over previous optoacoustic methods, potentially serving as a valuable tool for imaging tissue pathophysiology. PMID:27358000

  3. Energy spectra of secondary neutrons produced by high energy bremsstrahlung in carbon, nitrogen, oxygen and tissue

    International Nuclear Information System (INIS)

    Neutron energy spectra in carbon, nitrogen and oxygen were calculated for various bremsstrahlung end-point energies and, from these, tissue spectra were calculated using the tissue equivalent molecular formula C5H40O18N. The method involves folding the known bremsstrahlung spectrum shape with the cross section for each possible decay mode in each element which leads to neutron production. The partial photoneutron cross sections used have been derived from published data

  4. Simultaneous Blood–Tissue Exchange of Oxygen, Carbon Dioxide, Bicarbonate, and Hydrogen Ion

    OpenAIRE

    Dash, Ranjan K.; BASSINGTHWAIGHTE, JAMES B.

    2006-01-01

    A detailed nonlinear four-region (red blood cell, plasma, interstitial fluid, and parenchymal cell) axially distributed convection-diffusion-permeation-reaction-binding computational model is developed to study the simultaneous transport and exchange of oxygen (O2) and carbon dioxide (CO2) in the blood–tissue exchange system of the heart. Since the pH variation in blood and tissue influences the transport and exchange of O2 and CO2 (Bohr and Haldane effects), and since most ...

  5. [Influence of mastication on the amount of hemoglobin in human brain tissue].

    Science.gov (United States)

    Sasaki, A

    2001-03-01

    The purpose of this study was to investigate the influence of mastication on the amount of hemoglobin in human brain tissue. Nine healthy volunteers (6 males and 3 females) participated in this study. They underwent two tasks: 1) at rest, 2) gum-chewing. In seven of the nine (4 males and 3 females), experimental occlusal interference was applied to the first molar of the mandibule on the habitual masticatory side. They underwent the gum-chewing task. To evaluate the amount of hemoglobin, both the hemoglobin oxygenation state and blood volume during gum-chewing were measured in the frontal region, using near-infrared spectroscopy. The amount of total-hemoglobin (blood volume) and oxyhemoglobin of subjects significantly increased during gum-chewing (p < 0.01). When the subjects finished gum-chewing, both levels returned to the original levels. When experimental occlusal interference was imposed on the subject, the amount of them significantly decreased compared with subjects without experimental occlusal interference (p < 0.05). The results suggested that increases of cerebral blood flow in the frontal region were not due to the mandibular movement, and that human brain activity caused by mastication was not only in the cortical masticatory area but also in the frontal region.

  6. Dynamically monitoring tissue factor and tissue factor pathway inhibitor following secondary brain injury

    Institute of Scientific and Technical Information of China (English)

    吴雪海; 施小燕; 干建新; 卢兴国; 江观玉; 周君富

    2003-01-01

    Objective: To study the altering rule of coagulation function at molecular level in patients with secondary brain injury (SBI).Methods: Tissue factor (TF) and tissue factor pathway inhibitor (TFPI) were studied in 32 patients 1, 2, 3 and 7 days after craniocerebral injury. Repeated cranial CT scans and platelet counts were made simultaneously. Same measurements were done in 30 normal adults except CT scan.Results: No obvious difference was found in age, sex and platelet count between the injured and the normal groups. TFPI/TF decreased markedly in the first week after injury in patients with SBI, but only decreased on the 7th day in the patients without obvious SBI. For the patients who developed delayed intracranial hematoma (DIH) or hematoma enlargement, TF rose only 1 and 2 days after injury, but TFPI had a tendency to rise again after a fall on the 3rd day. For those patients who developed no DIH, TF rose all the time within the 1st week.Conclusions: Decrease of TFPI/TF for a long time, especially within 3 days after injury, may be one of the most important reasons for SBI. High expression of TF for a relative short time and increase of TFPI after a fall within 3 days may be one of the important reasons for DIH or hematoma enlargement.

  7. Detection of CCl/sub 4/-induced oxidation of hepatic tissue in vivo by oxygen-18 tracing

    Energy Technology Data Exchange (ETDEWEB)

    Hatch, G.E.; Santrock, J.; Slade, R.; Hayes, J.M.

    1988-01-01

    Oxygen can become a damaging influence in tissues and cells exposed to environmental pollutants. This paper describes the first application of a new technique for tracing oxygen in tissues exposed to pollutants. Carbon tetrachloride (CCl/sub 4/) was found to cause oxidation of liver tissue in rats which was measurable using oxygen-18 labeling procedures. Rats that breathed oxygen-18 while being exposed to CCl/sub 4/ were found to have oxidized lipids, macromolecules, and water-soluble substances in their livers. The techniques outlined in the paper should be useful for elucidating mechanisms of injury and increased aging of tissues exposed to pollutants.

  8. Characterizing Multiscale Mechanical Properties of Brain Tissue Using Atomic Force Microscopy, Impact Indentation, and Rheometry.

    Science.gov (United States)

    Canovic, Elizabeth Peruski; Qing, Bo; Mijailovic, Aleksandar S; Jagielska, Anna; Whitfield, Matthew J; Kelly, Elyza; Turner, Daria; Sahin, Mustafa; Van Vliet, Krystyn J

    2016-01-01

    To design and engineer materials inspired by the properties of the brain, whether for mechanical simulants or for tissue regeneration studies, the brain tissue itself must be well characterized at various length and time scales. Like many biological tissues, brain tissue exhibits a complex, hierarchical structure. However, in contrast to most other tissues, brain is of very low mechanical stiffness, with Young's elastic moduli E on the order of 100s of Pa. This low stiffness can present challenges to experimental characterization of key mechanical properties. Here, we demonstrate several mechanical characterization techniques that have been adapted to measure the elastic and viscoelastic properties of hydrated, compliant biological materials such as brain tissue, at different length scales and loading rates. At the microscale, we conduct creep-compliance and force relaxation experiments using atomic force microscope-enabled indentation. At the mesoscale, we perform impact indentation experiments using a pendulum-based instrumented indenter. At the macroscale, we conduct parallel plate rheometry to quantify the frequency dependent shear elastic moduli. We also discuss the challenges and limitations associated with each method. Together these techniques enable an in-depth mechanical characterization of brain tissue that can be used to better understand the structure of brain and to engineer bio-inspired materials. PMID:27684097

  9. Phospholipase A2 changes and its significance on brain tissue of rat in severe acute pancreatitis

    Institute of Scientific and Technical Information of China (English)

    Yao Xuan; Chen Xi; Ji Zongzheng

    2007-01-01

    Objective To survey changes and the significance of phospholipase A2(PLA2) on brain tissue of SD rat in acute pancreatitis. Methods With retrograde injection of 3% taurocholate sodium into pancreatic and biliary duct, rat model of severe acute pancreatitis (SAP) was made,and it included four groups: the control group, the sham-operation group, the SAP group and the PLA2 inhibitor-treated group of SAP. Serum amylases, PLA2 and PLA2 in brain tissue were measured and the brain tissue changes were observed. Results There were no significant difference in serum amylases, PLA2 and PLA2 in brain tissue between the sham-operation and the control groups; the levels of serum amylases, PLA2 and PLA2 in brain tissue in the SAP group were higher than those in the control. In the SAP group expansion and hemorrhage of meninges, intracephalic arteriolar hyperemia, in meninges and cephalic-parenchyma infiltration of inflammatory cells and interval broaden were observed, significant differences were found between two groups.Compared with the SAP group, the level of serum amylase, PLA2 and PLA2 in brain tissue were reduced significantly in the treatment group of SAP. Pathological damages in the treatment group were significantly reduced when compared with the SAP group. Conclusion PLA2 might play an important role in brain tissue damages in severe acute pancreatitis.

  10. Terahertz spectroscopy of brain tissue from a mouse model of Alzheimer's disease

    Science.gov (United States)

    Shi, Lingyan; Shumyatsky, Pavel; Rodríguez-Contreras, Adrián; Alfano, Robert

    2016-01-01

    The terahertz (THz) absorption and index of refraction of brain tissues from a mouse model of Alzheimer's disease (AD) and a control wild-type (normal) mouse were compared using THz time-domain spectroscopy (THz-TDS). Three dominating absorption peaks associated to torsional-vibrational modes were observed in AD tissue, at about 1.44, 1.8, and 2.114 THz, closer to the peaks of free tryptophan molecules than in normal tissue. A possible reason is that there is more free tryptophan in AD brain tissue, while in normal brain tissue more tryptophan is attached to other molecules. Our study suggests that THz-absorption modes may be used as an AD biomarker fingerprint in brain, and that THz-TDS is a promising technique for early diagnosis of AD.

  11. Design of a tissue oxygenation monitor and verification on human skin

    Science.gov (United States)

    Liu, Hongyuan; Kohl-Bareis, Matthias; Huang, Xiabing

    2011-07-01

    We report the design of a tissue oxygen and temperature monitor. The non-invasive, fibre based device monitors tissue haemoglobin (Hb) and oxygen saturation (SO2) and is based on white-light reflectance spectroscopy.Visible light with wavelengths in the 500 - 650nm range is utilized. The spectroscopic algorithm takes into account the tissue scattering and melanin absorption for the calculation of tissue haemoglobin concentration and oxygen saturation. The monitor can probe superficial layers of tissue with a high spatial resolution (mm3) and a high temporal resolution (40 Hz). It provides an accurate measurement with the accuracy of SO2 at 2 % and high reliability with less than 2 % variation of continuous SO2 measurement over 12 hours. It can also form a modular system when used in conjunction with a laser Doppler monitor, enabling simultaneous measurements of Hb, SO2 and blood flow. We found experimentally that the influence of the source-detector separation on the haemoglobin parameters is small. This finding is discussed by Monte Carlo simulations for the depth sensitivity profile. The influence of probe pressure and the skin pigmentation on the measurement parameters are assessed before in vivo experimental data is presented. The combination with laser Doppler flowmetry demonstrates the importance of a measurement of both the haemoglobin and the blood flow parameters for a full description of blood tissue perfusion. This is discussed in experimental data on human skin during cuff occlusion and after hyperemisation by a pharmacological cream. Strong correlation is observed between tissue oxygen (Hb and SO2) and blood flow measurements.

  12. Blood BDNF concentrations reflect brain-tissue BDNF levels across species

    DEFF Research Database (Denmark)

    Klein, Anders B; Williamson, Rebecca; Santini, Martin A;

    2011-01-01

    Brain-derived neurotrophic factor (BDNF) is involved in synaptic plasticity, neuronal differentiation and survival of neurons. Observations of decreased serum BDNF levels in patients with neuropsychiatric disorders have highlighted the potential of BDNF as a biomarker, but so far there have been...... no studies directly comparing blood BDNF levels to brain BDNF levels in different species. We examined blood, serum, plasma and brain-tissue BDNF levels in three different mammalian species: rat, pig, and mouse, using an ELISA method. As a control, we included an analysis of blood and brain tissue from...

  13. Identifying markers of pathology in SAXS data of malignant tissues of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Siu, K.K.W. [School of Physics and Materials Engineering, PO Box 27, Monash University, Victoria 3800 (Australia)]. E-mail: Karen.Siu@spme.monash.edu.au; Butler, S.M. [School of Computer Science and Software Engineering, PO Box 75, Monash University, Victoria 3800 (Australia); Beveridge, T. [School of Physics and Materials Engineering, PO Box 27, Monash University, Victoria 3800 (Australia); Gillam, J.E. [School of Physics and Materials Engineering, PO Box 27, Monash University, Victoria 3800 (Australia); Hall, C.J. [Daresbury Laboratory, Warrington, Cheshire WA4 4AD (United Kingdom); Kaye, A.H. [Department of Surgery, University of Melbourne, Parkville 3050 (Australia); Department of Neurosurgery, Royal Melbourne Hospital, Parkville 3050 (Australia); Lewis, R.A. [Monash Centre for Synchrotron Science, PO Box 27, Monash University, Victoria 3800 (Australia); Mannan, K. [Division of Neurosurgery, University of Saskatchewan, Saskatoon S7N 5E5 (Canada); McLoughlin, G. [Division of Neurosurgery, University of Saskatchewan, Saskatoon S7N 5E5 (Canada); Pearson, S. [Physics and Electronics, University of New England, Armidale, New South Wales 2351 (Australia); Round, A.R. [Department of Materials and Medical Sciences, Cranfield University, Wiltshire SN6 8LA (United Kingdom); Schueltke, E. [Division of Neurosurgery, University of Saskatchewan, Saskatoon S7N 5E5 (Canada); Department of Anatomy and Cell Biology, University of Saskatchewan, Saskatoon S7N 5E5 (Canada); Department of Neurological Science, Walton Medical Centre, University of Liverpool, L97 LJ (United Kingdom); Webb, G.I. [School of Computer Science and Software Engineering, PO Box 75, Monash University, Victoria 3800 (Australia); Wilkinson, S.J. [Department of Materials and Medical Sciences, Cranfield University, Wiltshire SN6 8LA (United Kingdom)

    2005-08-11

    Conventional neuropathological analysis for brain malignancies is heavily reliant on the observation of morphological abnormalities, observed in thin, stained sections of tissue. Small Angle X-ray Scattering (SAXS) data provide an alternative means of distinguishing pathology by examining the ultra-structural (nanometer length scales) characteristics of tissue. To evaluate the diagnostic potential of SAXS for brain tumors, data was collected from normal, malignant and benign tissues of the human brain at station 2.1 of the Daresbury Laboratory Synchrotron Radiation Source and subjected to data mining and multivariate statistical analysis. The results suggest SAXS data may be an effective classifier of malignancy.

  14. Ionic charge transport between blockages: Sodium cation conduction in freshly excised bulk brain tissue

    Energy Technology Data Exchange (ETDEWEB)

    Emin, David, E-mail: emin@unm.edu [Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131 (United States); Akhtari, Massoud [Semple Institutes for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095 (United States); Ellingson, B. M. [Department of Radiology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095 (United States); Mathern, G. W. [Department of Neurosurgery, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095 (United States)

    2015-08-15

    We analyze the transient-dc and frequency-dependent electrical conductivities between blocking electrodes. We extend this analysis to measurements of ions’ transport in freshly excised bulk samples of human brain tissue whose complex cellular structure produces blockages. The associated ionic charge-carrier density and diffusivity are consistent with local values for sodium cations determined non-invasively in brain tissue by MRI (NMR) and diffusion-MRI (spin-echo NMR). The characteristic separation between blockages, about 450 microns, is very much shorter than that found for sodium-doped gel proxies for brain tissue, >1 cm.

  15. Non-invasive monitoring of tissue oxygenation during laparoscopic donor nephrectomy

    Directory of Open Access Journals (Sweden)

    Kirk Allan D

    2008-04-01

    Full Text Available Abstract Background Standard methods for assessment of organ viability during surgery are typically limited to visual cues and tactile feedback in open surgery. However, during laparoscopic surgery, these processes are impaired. This is of particular relevance during laparoscopic renal donation, where the condition of the kidney must be optimized despite considerable manipulation. However, there is no in vivo methodology to monitor renal parenchymal oxygenation during laparoscopic surgery. Methods We have developed a method for the real time, in vivo, whole organ assessment of tissue oxygenation during laparoscopic nephrectomy to convey meaningful biological data to the surgeon during laparoscopic surgery. We apply the 3-CCD (charge coupled device camera to monitor qualitatively renal parenchymal oxygenation with potential real-time video capability. Results We have validated this methodology in a porcine model across a range of hypoxic conditions, and have then applied the method during clinical laparoscopic donor nephrectomies during clinically relevant pneumoperitoneum. 3-CCD image enhancement produces mean region of interest (ROI intensity values that can be directly correlated with blood oxygen saturation measurements (R2 > 0.96. The calculated mean ROI intensity values obtained at the beginning of the laparoscopic nephrectomy do not differ significantly from mean ROI intensity values calculated immediately before kidney removal (p > 0.05. Conclusion Here, using the 3-CCD camera, we qualitatively monitor tissue oxygenation. This means of assessing intraoperative tissue oxygenation may be a useful method to avoid unintended ischemic injury during laparoscopic surgery. Preliminary results indicate that no significant changes in renal oxygenation occur as a result of pneumoperitoneum.

  16. Expression of hypoxia-inducible factor 1 alpha and oligodendrocyte lineage gene-1 in cultured brain slices after oxygen-glucose deprivation

    Institute of Scientific and Technical Information of China (English)

    Hong Cui; Weijuan Han; Lijun Yang; Yanzhong Chang

    2013-01-01

    Oligodendrocyte lineage gene-1 expressed in oligodendrocytes may trigger the repair of neuronal myelin impairment, and play a crucial role in myelin repair. Hypoxia-inducible factor 1α, a transcription factor, is of great significance in premature infants with hypoxic-ischemic brain damage. There is little evidence of direct regulatory effects of hypoxia-inducible factor 1α on oligodendrocyte lineage gene-1. In this study, brain slices of Sprague-Dawley rats were cultured and subjected to oxygen-glucose deprivation. Then, slices were transfected with hypoxia-inducible factor 1α or oligodendrocyte lineage gene-1. The expression levels of hypoxia-inducible factor 1α and oligodendrocyte lineage gene-1 were significantly up-regulated in rat brains prior to transfection, as detected by immunohistochemical staining. Eight hours after transfection of slices with hypoxia-inducible factor 1α, oligodendrocyte lineage gene-1 expression was upregulated, and reached a peak 24 hours after transfection. Oligodendrocyte lineage gene-1 transfection induced no significant differences in hypoxia-inducible factor 1α levels in rat brain tissues with oxygen-glucose deprivation. These experimental findings indicate that hypoxia-inducible factor 1α can regulate oligodendrocyte lineage gene-1 expression in hypoxic brain tissue, thus repairing the neural impairment.

  17. Estimation of Drug Binding to Brain Tissue: Methodology and in Vivo Application of a Distribution Assay in Brain Polar Lipids.

    Science.gov (United States)

    Belli, Sara; Assmus, Frauke; Wagner, Bjoern; Honer, Michael; Fischer, Holger; Schuler, Franz; Alvarez-Sánchez, Rubén

    2015-12-01

    The unbound drug concentration-effect relationship in brain is a key aspect in CNS drug discovery and development. In this work, we describe an in vitro high-throughput distribution assay between an aqueous buffer and a microemulsion of porcine brain polar lipids (BPL). The derived distribution coefficient LogDBPL was applied to the prediction of unbound drug concentrations in brain (Cu,b) and nonspecific binding to brain tissue. The in vivo relevance of the new assay was assessed for a large set of proprietary drug candidates and CNS drugs by (1) comparing observed compound concentrations in rat CSF with Cu,b calculated using the LogDBPL assay in combination with total drug brain concentrations, (2) comparing Cu,b derived from LogDBPL and total drug brain concentrations to Cu,b estimated using in vitro P-glycoprotein efflux ratio data and unbound drug plasma levels, and (3) comparing tissue nonspecific binding data from human brain autoradiography studies for 17 PET tracer candidates to distribution in BPL. In summary, the LogDBPL assay provides a predicted drug fraction unbound in brain tissue that is nearly identical to brain homogenate equilibrium dialysis with an estimation of in vivo Cu,b that is superior to LogD in octanol. LogDBPL complements the approach for predicting Cu,b based on in vitro P-glycoprotein efflux ratio and in vivo unbound plasma concentration and stands as a fast and cost-effective tool for nonspecific brain binding optimization of PET ligand candidates.

  18. CCl4 induces tissue-type plasminogen activator in rat brain; protective effects of oregano, rosemary or vitamin E.

    Science.gov (United States)

    Lavrentiadou, Sophia N; Tsantarliotou, Maria P; Zervos, Ioannis A; Nikolaidis, Efstathios; Georgiadis, Marios P; Taitzoglou, Ioannis A

    2013-11-01

    The high metabolic rate and relatively low antioxidant defenses of the lipid-rich brain tissue render it highly susceptible to reactive oxygen species (ROS) and oxidative stress, whereas the implication of ROS in the pathogenesis of several diseases in the central nervous system is well-established. The plasminogen activator (PA) system is a key modulator of extracellular proteolysis, extracellular matrix remodeling and neuronal cell signaling and has been implicated in the pathogenesis of these diseases. This study evaluates the role of tissue-type PA (t-PA) in oxidative stress and the protective role of dietary antioxidants in the rat brain. We used the CCl4 experimental model of ROS-induced lipid peroxidation and evaluated the antioxidant effect of oregano, rosemary or vitamin E. CCl4-treated Wistar rats exhibited elevated brain t-PA activity, which was decreased upon long-term administration of oregano, rosemary or vitamin E. PA inhibitor-1 (PAI-1) activity was also slightly elevated by CCl4, but this increase was not affected by the antioxidants. We hypothesize that the CCl4-induced t-PA activity indicates extracellular proteolytic activity that may be linked to neuronal cell death and brain damage. Vitamin E or antioxidants present in oregano or rosemary are effective in inhibiting t-PA elevation and can be considered as a potential protection against neuronal damage. PMID:23831191

  19. Effect of prophylactic hyperbaric oxygen treatment for radiation-induced brain injury after stereotactic radiosurgery of brain metastases

    International Nuclear Information System (INIS)

    Purpose: The purpose of the present study was to evaluate the prophylactic effect of hyperbaric oxygen (HBO) therapy for radiation-induced brain injury in patients with brain metastasis treated with stereotactic radiosurgery (SRS). Methods and Materials: The data of 78 patients presenting with 101 brain metastases treated with SRS between October 1994 and September 2003 were retrospectively analyzed. A total of 32 patients with 47 brain metastases were treated with prophylactic HBO (HBO group), which included all 21 patients who underwent subsequent or prior radiotherapy and 11 patients with common predictors of longer survival, such as inactive extracranial tumors and younger age. The other 46 patients with 54 brain metastases did not undergo HBO (non-HBO group). Radiation-induced brain injuries were divided into two categories, white matter injury (WMI) and radiation necrosis (RN), on the basis of imaging findings. Results: Radiation-induced brain injury occurred in 5 lesions (11%) in the HBO group (2 WMIs and 3 RNs) and in 11 (20%) in the non-HBO group (9 WMIs and 2 RNs). The WMI was less frequent for the HBO group than for the non-HBO group (p = 0.05), although multivariate analysis by logistic regression showed that WMI was not significantly correlated with HBO (p = 0.07). The 1-year actuarial probability of WMI was significantly better for the HBO group (2%) than for the non-HBO group (36%) (p < 0.05). Conclusions: The present study showed a potential value of prophylactic HBO for Radiation-induced WMIs, which justifies further evaluation to confirm its definite benefit

  20. Blood BDNF concentrations reflect brain-tissue BDNF levels across species

    DEFF Research Database (Denmark)

    Klein, Anders B; Williamson, Rebecca; Santini, Martin A;

    2011-01-01

    Brain-derived neurotrophic factor (BDNF) is involved in synaptic plasticity, neuronal differentiation and survival of neurons. Observations of decreased serum BDNF levels in patients with neuropsychiatric disorders have highlighted the potential of BDNF as a biomarker, but so far there have been...... no studies directly comparing blood BDNF levels to brain BDNF levels in different species. We examined blood, serum, plasma and brain-tissue BDNF levels in three different mammalian species: rat, pig, and mouse, using an ELISA method. As a control, we included an analysis of blood and brain tissue from...... conditional BDNF knockout mice and their wild-type littermates. Whereas BDNF could readily be measured in rat blood, plasma and brain tissue, it was undetectable in mouse blood. In pigs, whole-blood levels of BDNF could not be measured with a commercially available ELISA kit, but pig plasma BDNF levels (mean...

  1. Effect of montelukast on the expression of interleukin-18, telomerase reverse transcriptase, and Bcl-2 in the brain tissue of neonatal rats with hypoxic-ischemic brain damage.

    Science.gov (United States)

    Liu, J L; Zhao, X H; Zhang, D L; Zhang, J B; Liu, Z H

    2015-01-01

    The aim of this study was to investigate the effect of montelukast on the expression of interleukin (IL)-18, telomerase reverse transcriptase (TERT), and Bcl-2 in the brain tissue of neonatal rats with hypox-ic-ischemic brain damage (HIBD). To establish the model of HIBD, 8% oxygen was applied to rats after the unilateral carotid artery was ligated. Twenty rats were randomly assigned to the control group, while another 40 were used to establish the HIBD model and were randomly divided equally into model group and treatment group. A 0.1 mg/kg dose of montelukast or an equal volume of saline was intraperitoneally injected to the rats in the treatment group and the model group, respectively. Brain tissue from 4 rats in each group was sampled at 0, 6, 12, 24, and 72 h after brain damage, and immunohistochemistry was used to measure IL-18, TERT and Bcl-2 expressions. IL-18, TERT, and Bcl-2 levels increased after 12 h in both the model group and treatment group, peaked after 48 h, and then decreased. Although not statistically significant, IL-18, TERT, and Bcl-2 expressions after 24, 48, and 96 h were all lower in the treatment group than those in the model group. In conclusion, montelukast has a protective effect on the cerebral tissue of neonatal rats with HIBD, and may mediate an increase of TERT and Bcl-2 levels but not of IL-18. Further study is required to elucidate the mechanism of the protective effect of montelukast on HIBD. PMID:26345821

  2. Potato chip intake increases ascorbic acid levels and decreases reactive oxygen species in SMP30/GNL knockout mouse tissues.

    Science.gov (United States)

    Kondo, Yoshitaka; Sakuma, Rui; Ichisawa, Megumi; Ishihara, Katsuyuki; Kubo, Misako; Handa, Setsuko; Mugita, Hiroyuki; Maruyama, Naoki; Koga, Hidenori; Ishigami, Akihito

    2014-09-24

    Potato chips (PC) contain abundant amounts of the free radical scavenger ascorbic acid (AA) due to the rapid dehydration of potato tubers (Solanum tuberosum) that occurs during frying. To evaluate the antioxidant activity of PC, this study examined reactive oxygen species (ROS) levels in tissues from SMP30/GNL knockout (KO) mice that cannot synthesize AA and determined AA and ROS levels after the animals were fed 20 and 10% PC diets for 7 weeks. Compared with AA-sufficient mice, AA-depleted SMP30/GNL KO mice showed high ROS levels in tissues. SMP30/GNL KO mice fed a PC diet showed high AA and low ROS levels in the brain, heart, lung, testis, soleus muscle, plantaris muscle, stomach, small intestine, large intestine, eyeball, and epididymal fat compared with AA-depleted mice. The data suggest that PC intake increases AA levels and enhances ROS scavenging activity in tissues of SMP30/GNL KO mice, which are a promising model for evaluating the antioxidant activity of foods. PMID:25180784

  3. Sleep is not just for the brain: transcriptional responses to sleep in peripheral tissues

    OpenAIRE

    Anafi, Ron C.; Pellegrino, Renata; Shockley, Keith R.; Romer, Micah; Tufik, Sergio; Pack, Allan I.

    2013-01-01

    Background Many have assumed that the primary function of sleep is for the brain. We evaluated the molecular consequences of sleep and sleep deprivation outside the brain, in heart and lung. Using microarrays we compared gene expression in tissue from sleeping and sleep deprived mice euthanized at the same diurnal times. Results In each tissue, nearly two thousand genes demonstrated statistically significant differential expression as a function of sleep/wake behavioral state. To mitigate the...

  4. Comparison of Cerebral Oxygen Saturation and Cerebral Perfusion Computed Tomography in Cerebral Blood Flow in Patients with Brain Injury.

    Science.gov (United States)

    Trofimov, Alexey O; Kalentiev, George; Voennov, Oleg; Grigoryeva, Vera

    2016-01-01

    The purpose of this study was to determine the relationship between cerebral tissue oxygen saturation and cerebral blood volume in patients with traumatic brain injury. Perfusion computed tomography of the brain was performed in 25 patients with traumatic brain injury together with simultaneous SctO2 level measurement using cerebral near-infrared oxymetry. The mean age of the injured persons was 34.5±15.6 years (range 15-65); 14 men, 11 women. The Injury Severity Score (ISS) values were 44.4±9.7 (range 25-81). The Glasgow Coma Score (GCS) mean value before the study was 10.6±2.1 (range 5-13). SctO2 ranged from 51 to 89%, mean 62±8.2%. Cerebral blood volume (CBV) values were 2.1±0.67 ml/100 g (min 1.1; max 4.3 ml/100 g). Cerebral blood flow (CBF) was 31.99±13.6 ml/100 g×min. Mean transit time (MTT) values were 5.7±4.5 s (min 2.8; max 34.3 s). The time to peak (TTP) was 22.2±3.1 s. A statistically significant correlation was found between SctO2 level and cerebral blood volume (CBV) level (R=0.9; pperfusion.

  5. Baseline oxygenation in the brain: Correlation between respiratory-calibration and susceptibility methods.

    Science.gov (United States)

    Fan, Audrey P; Schäfer, Andreas; Huber, Laurentius; Lampe, Leonie; von Smuda, Steffen; Möller, Harald E; Villringer, Arno; Gauthier, Claudine J

    2016-01-15

    New MRI methods for noninvasive imaging of baseline oxygen extraction fraction (OEF) in the brain show great promise. Quantitative O2 imaging (QUO2) applies a biophysical model to measure OEF in tissue from BOLD, cerebral blood flow (CBF), and end-tidal O2 (ETO2) signals acquired during two or more gas manipulations. Alternatively, quantitative susceptibility mapping (QSM) maps baseline OEF along cerebral vessels based on the deoxyhemoblogin (dHb) susceptibility shift between veins and water. However, these approaches have not been carefully compared to each other or to known physiological signals. The aims of this study were to compare OEF values by QUO2 and QSM; and to see if baseline OEF relates to BOLD and CBF changes during a visual task. Simultaneous BOLD and arterial spin labeling (ASL) scans were acquired at 7T in 11 healthy subjects continuously during hypercapnia (5% CO2, 21% O2), hyperoxia (100% O2), and carbogen (5% CO2, 95% O2) for QUO2 analysis. Separate BOLD-ASL scans were acquired during a checkerboard stimulus to identify functional changes in the visual cortex. Gradient echo phase images were also collected at rest for QSM reconstruction of OEF along cerebral veins draining the visual cortex. Mean baseline OEF was (43.5±14)% for QUO2 with two gases, (42.3±17)% for QUO2 with three gases, and (29.4±3)% for QSM across volunteers. Three-gas QUO2 values of OEF correlated with QSM values of OEF (P=0.03). However, Bland-Altman analysis revealed that QUO2 tended to measure higher baseline OEF with respect to QSM, which likely results from underestimation of the hyperoxic BOLD signal and low signal-to-noise ratio of the ASL acquisitions. Across subjects, the percent CBF change during the visual task correlated with OEF measured by 3-gas QUO2 (P<0.04); and by QSM (P=0.035), providing evidence that the new methods measure true variations in brain physiology across subjects.

  6. Artificial membrane-binding proteins stimulate oxygenation of stem cells during engineering of large cartilage tissue

    Science.gov (United States)

    Armstrong, James P. K.; Shakur, Rameen; Horne, Joseph P.; Dickinson, Sally C.; Armstrong, Craig T.; Lau, Katherine; Kadiwala, Juned; Lowe, Robert; Seddon, Annela; Mann, Stephen; Anderson, J. L. Ross; Perriman, Adam W.; Hollander, Anthony P.

    2015-06-01

    Restricted oxygen diffusion can result in central cell necrosis in engineered tissue, a problem that is exacerbated when engineering large tissue constructs for clinical application. Here we show that pre-treating human mesenchymal stem cells (hMSCs) with synthetic membrane-active myoglobin-polymer-surfactant complexes can provide a reservoir of oxygen capable of alleviating necrosis at the centre of hyaline cartilage. This is achieved through the development of a new cell functionalization methodology based on polymer-surfactant conjugation, which allows the delivery of functional proteins to the hMSC membrane. This new approach circumvents the need for cell surface engineering using protein chimerization or genetic transfection, and we demonstrate that the surface-modified hMSCs retain their ability to proliferate and to undergo multilineage differentiation. The functionalization technology is facile, versatile and non-disruptive, and in addition to tissue oxygenation, it should have far-reaching application in a host of tissue engineering and cell-based therapies.

  7. Isolation and Functional Assessment of Mitochondria from Small Amounts of Mouse Brain Tissue

    OpenAIRE

    Chinopoulos, Christos; Zhang, Steven F.; Thomas, Bobby; Ten, Vadim; Starkov, Anatoly A.

    2011-01-01

    Recent discoveries have brought mitochondria functions in focus of the neuroscience research community and greatly stimulated the demand for approaches to study mitochondria dysfunction in neurodegenerative diseases. Many mouse disease models have been generated, but studying mitochondria isolated from individual mouse brain regions is a challenge because of small amount of the available brain tissue. Conventional techniques for isolation and purification of mitochondria from mouse brain subr...

  8. Differentiation of cancerous and normal brain tissue using label free fluorescence and Stokes shift spectroscopy

    Science.gov (United States)

    Zhou, Yan; Wang, Leana; Liu, Cheng-hui; He, Yong; Yu, Xinguang; Cheng, Gangge; Wang, Peng; Shu, Cheng; Alfano, Robert R.

    2016-03-01

    In this report, optical biopsy was applied to diagnose human brain cancer in vitro for the identification of brain cancer from normal tissues by native fluorescence and Stokes shift spectra (SSS). 77 brain specimens including three types of human brain tissues (normal, glioma and brain metastasis of lung cancers) were studied. In order to observe spectral changes of fluorophores via fluorescence, the selected excitation wavelength of UV at 300 and 340 nm for emission spectra and a different Stokes Shift spectra with intervals Δλ = 40 nm were measured. The fluorescence spectra and SSS from multiple key native molecular markers, such as tryptophan, collagen, NADH, alanine, ceroid and lipofuscin were observed in normal and diseased brain tissues. Two diagnostic criteria were established based on the ratios of the peak intensities and peak position in both fluorescence and SSS spectra. It was observed that the ratio of the spectral peak intensity of tryptophan (340 nm) to NADH (440 nm) increased in glioma, meningioma (benign), malignant meninges tumor, and brain metastasis of lung cancer tissues in comparison with normal tissues. The ratio of the SS spectral peak (Δλ = 40 nm) intensities from 292 nm to 366 nm had risen similarly in all grades of tumors.

  9. Mimicking brain tissues by doping scatterers into gelatin tissue phantoms and determination of chemical species responsible for NMPPAS

    Science.gov (United States)

    Dahal, Sudhir; Cullum, Brian M.

    2012-06-01

    It has been shown that non-resonant multiphoton photoacoustic spectroscopy (NMPPAS) has a great potential to be used as a high resolution surgical guidance technique during brain tumor surgery due to its ability of non-invasive or minimally invasive tumor differentiation. However, for experimental purposes associated with method validation, the use of real tissues is not always ideal because of issues such as availability, safety, storage, chemical doping, necessary control of size and shape, etc. To overcome these issues, tissue phantoms made from animal tissues and/or biochemical constituents, are often employed for such analyses. This work demonstrates the ability to develop and characterize gelatin based tissue phantoms with comparable optical and acoustic properties to real tissues by doping the phantoms with a scattering substance, 0.3 μm diameter Al2O3 particles. Using these phantoms, light scattering coefficients (μs) of 39 cm-1 have been generated, which are comparable to real brain tissue, thus making them a great alternative to real tissue for validation studies. In addition, this work also investigates the non-fluorescent species NAD+ found in the tissues, to evaluate its potential for being detected by NMPPAS. NMPPAS spectra of NAD+ shows a very promising beginning to determine other chemical species such as flavins, collagen, tryptophan, etc responsible for NMPPAS spectral signatures, associated with tumorogenesis.

  10. [Effect of hyperbaric oxygenation on local tissue blood flow to a small intestine transplant intended for esophagoplasty].

    Science.gov (United States)

    Vinnitskiĭ, L I; Piuskiulian, L I; Zhidkov, I L; Demurov, E A

    1981-04-01

    The time course of the local tissue blood flow in the small intestinal graft used for esophagoplasty was studied in 54 acute experiments on rabbits exposed to hyperbaric oxygenation (1 hour, 2 ata). It has been shown that hyperbaric oxygenation prevents alterations in the local tissue blood flow in the small intestine. This fact provides evidence in favour of hyperbaric oxygenation application under clinical conditions.

  11. Discovery of Undescribed Brain Tissue Changes Around Implanted Microelectrode Arrays

    OpenAIRE

    Himanshi Desai

    2012-01-01

    Brain-implantable microelectrode arrays are devicesdesigned to record or electrically stimulate the activity ofneurons in the brain. These devices hold the potential tohelp treat epilepsy, paralysis, blindness, and deafness, andalso provide researchers with insights into a varietyof neural processes, such as memory formation.While these devices have a very promising future,researchers are discovering that their long-termfunctionality is greatly limited by the brain’s naturalimmune response to...

  12. Tissue oxygen monitoring by photoacoustic lifetime imaging (PALI) and its application to image-guided photodynamic therapy (PDT)

    Science.gov (United States)

    Shao, Qi; Morgounova, Ekaterina; Ashkenazi, Shai

    2015-03-01

    The oxygen partial pressure (pO2), which results from the balance between oxygen delivery and its consumption, is a key component of the physiological state of a tissue. Images of oxygen distribution can provide essential information for identifying hypoxic tissue and optimizing cancer treatment. Previously, we have reported a noninvasive in vivo imaging modality based on photoacoustic lifetime. The technique maps the excited triplet state of oxygen-sensitive dye, thus reflects the spatial and temporal distribution of tissue oxygen. We have applied PALI on tumor on small animals to identify hypoxia area. We also showed that PALI is able monitor changes of tissue oxygen, in an acute ischemia and breathing modulation model. Here we present our work on developing a treatment/imaging modality (PDT-PALI) that integrates PDT and a combined ultrasound/photoacoustic imaging system. The system provides real-time feedback of three essential parameters namely: tissue oxygen, light penetration in tumor location, and distribution of photosensitizer. Tissue oxygen imaging is performed by applying PALI, which relies on photoacoustic probing of oxygen-dependent, excitation lifetime of Methylene Blue (MB) photosensitizer. Lifetime information can also be used to generate image showing the distribution of photosensitizer. The level and penetration depth of PDT illumination can be deduced from photoacoustic imaging at the same wavelength. All images will be combined with ultrasound B-mode images for anatomical reference.

  13. Effect of HSH on oxygen free radicals and histopathological change of brain tissue in dog with acute intracranial hypertension and hemorrhagic shock%高渗氯化钠羟乙基淀粉注射液输注对急性颅内高压伴失血性休克犬脑组织病理学及氧自由基的影响

    Institute of Scientific and Technical Information of China (English)

    徐翔; 古妙宁; 肖金仿; 肖华平; 赵振龙; 刘高望

    2008-01-01

    Objective To observe the effects of hypertonic sodium chloride hydroxyethyl starch 40 injection(HSH) on recovering of circulating blood volume, lessening edema of brain tissue and decreasing oxygen free radicals in dog with acute intracranial hypertension and hemorrhagic shock. Methods 20 healthy dogs were randomly divided into 4 groups: Group hydroxyethyl starch (HES), Group Ringer- lactate solution (RL), Group hypertonic saline solution (HS) and Group HSH. Acute intracranial hypertension and hemorrhagic shock were made by injecting water into epidural balloon and bleeding artery. Corresponding injections were infused respectively 1h after shock. Mean arterial blood pressure (MAP), central venous pressure (CVP), heart rate (HR) and intracranial pressure (ICP) were monitored, and the level of superoxide dismutase (SOD) and malondialdehyde (MDA) in brain tissue were examined. Specimens of brain tissue were prepared for pathological examination. Results After resuscitation, injections of 4 groups can effectively increase MAP( P < 0.05 )while ICP of Group HES and Group RL significantly increased (P < 0.05 ). Two hours after resuscitation, MAP of Group HS began to decrease (P < 0.05 ). Four hours after resuscitation, only Group HSH can maintain an higher MAP and lower ICP. MDA and SOD levels in Group HSH were evidently lower than other groups at four hours after resuscitation (P < 0. 05). Pathological examination revealed less injury in Group HSH than other groups. Conclusion HSH could effectively resuscitate hemorrhagic shock, decrease ICP, reduce oxygen free radicals levels in brain tissue and relieve tissue ischemia/reperfusion injury.%目的 观察高渗氯化钠羟乙基淀粉40注射液(HSH)在犬急性颅内高压伴失血性休克模型中恢复循环血容量、减轻脑组织水肿和降低脑组织氧自由基含量的作用.方法 健康杂种犬20只,采用硬膜外球囊注水和动脉放血的方法复制急性颅内高压伴失血性休克模型.动物

  14. In vivo detection of epileptic brain tissue using static fluorescence and diffuse reflectance spectroscopy.

    Science.gov (United States)

    Yadav, Nitin; Bhatia, Sanjiv; Ragheb, John; Mehta, Rupal; Jayakar, Prasanna; Yong, William; Lin, Wei-Chiang

    2013-02-01

    Diffuse reflectance and fluorescence spectroscopy are used to detect histopathological abnormalities of an epileptic brain in a human subject study. Static diffuse reflectance and fluorescence spectra are acquired from normal and epileptic brain areas, defined by electrocorticography (ECoG), from pediatric patients undergoing epilepsy surgery. Biopsy specimens are taken from the investigated sites within an abnormal brain. Spectral analysis reveals significant differences in diffuse reflectance spectra and the ratio of fluorescence and diffuse reflectance spectra from normal and epileptic brain areas defined by ECoG and histology. Using these spectral differences, tissue classification models with accuracy above 80% are developed based on linear discriminant analysis. The differences between the diffuse reflectance spectra from the normal and epileptic brain areas observed in this study are attributed to alterations in the static hemodynamic characteristics of an epileptic brain, suggesting a unique association between the histopathological and the hemodynamic abnormalities in an epileptic brain.

  15. No oxygen? No problem! Intrinsic brain tolerance to hypoxia in vertebrates.

    Science.gov (United States)

    Larson, John; Drew, Kelly L; Folkow, Lars P; Milton, Sarah L; Park, Thomas J

    2014-04-01

    Many vertebrates are challenged by either chronic or acute episodes of low oxygen availability in their natural environments. Brain function is especially vulnerable to the effects of hypoxia and can be irreversibly impaired by even brief periods of low oxygen supply. This review describes recent research on physiological mechanisms that have evolved in certain vertebrate species to cope with brain hypoxia. Four model systems are considered: freshwater turtles that can survive for months trapped in frozen-over lakes, arctic ground squirrels that respire at extremely low rates during winter hibernation, seals and whales that undertake breath-hold dives lasting minutes to hours, and naked mole-rats that live in crowded burrows completely underground for their entire lives. These species exhibit remarkable specializations of brain physiology that adapt them for acute or chronic episodes of hypoxia. These specializations may be reactive in nature, involving modifications to the catastrophic sequelae of oxygen deprivation that occur in non-tolerant species, or preparatory in nature, preventing the activation of those sequelae altogether. Better understanding of the mechanisms used by these hypoxia-tolerant vertebrates will increase appreciation of how nervous systems are adapted for life in specific ecological niches as well as inform advances in therapy for neurological conditions such as stroke and epilepsy. PMID:24671961

  16. Polyploidization of glia in neural development links tissue growth to blood-brain barrier integrity.

    Science.gov (United States)

    Unhavaithaya, Yingdee; Orr-Weaver, Terry L

    2012-01-01

    Proper development requires coordination in growth of the cell types composing an organ. Many plant and animal cells are polyploid, but how these polyploid tissues contribute to organ growth is not well understood. We found the Drosophila melanogaster subperineurial glia (SPG) to be polyploid, and ploidy is coordinated with brain mass. Inhibition of SPG polyploidy caused rupture of the septate junctions necessary for the blood-brain barrier. Thus, the increased SPG cell size resulting from polyploidization is required to maintain the SPG envelope surrounding the growing brain. Polyploidization likely is a conserved strategy to coordinate tissue growth during organogenesis, with potential vertebrate examples.

  17. Measurement of characteristic prompt gamma rays emitted from oxygen and carbon in tissue-equivalent samples during proton beam irradiation

    OpenAIRE

    Polf, Jerimy C.; Panthi, Rajesh; Mackin, Dennis S; McCleskey, Matt; Saastamoinen, Antti; Roeder, Brian T; Beddar, Sam

    2013-01-01

    The purpose of this work was to characterize how prompt gamma (PG) emission from tissue changes as a function of carbon and oxygen concentration, and to assess the feasibility of determining elemental concentration in tissues irradiated with proton beams. For this study, four tissue-equivalent water-sucrose samples with differing densities and concentrations of carbon, hydrogen, and oxygen were irradiated with a 48 MeV proton pencil beam. The PG spectrum emitted from each sample was measured ...

  18. Influence of Negative-Pressure Wound Therapy on Tissue Oxygenation of the Foot

    OpenAIRE

    Shon, Yoo-Seok; Lee, Ye-Na; Jeong, Seong-Ho; Dhong, Eun-Sang; Han, Seung-Kyu

    2014-01-01

    Background Negative-pressure wound therapy (NPWT) is believed to accelerate wound healing by altering wound microvascular blood flow. Although many studies using laser Doppler have found that NPWT increases perfusion, recent work using other modalities has demonstrated that perfusion is reduced. The purpose of this study was to investigate the influence of NPWT on tissue oxygenation of the foot, which is the most sensitive region of the body to ischemia. Methods Transcutaneous partial pressur...

  19. Evaluation of three-dimensional anisotropic head model for mapping realistic electromagnetic fields of brain tissues

    Directory of Open Access Journals (Sweden)

    Woo Chul Jeong

    2015-08-01

    Full Text Available Electromagnetic fields provide fundamental data for the imaging of electrical tissue properties, such as conductivity and permittivity, in recent magnetic resonance (MR-based tissue property mapping. The induced voltage, current density, and magnetic flux density caused by externally injected current are critical factors for determining the image quality of electrical tissue conductivity. As a useful tool to identify bio-electromagnetic phenomena, precise approaches are required to understand the exact responses inside the human body subject to an injected currents. In this study, we provide the numerical simulation results of electromagnetic field mapping of brain tissues using a MR-based conductivity imaging method. First, we implemented a realistic three-dimensional human anisotropic head model using high-resolution anatomical and diffusion tensor MR images. The voltage, current density, and magnetic flux density of brain tissues were imaged by injecting 1 mA of current through pairs of electrodes on the surface of our head model. The current density map of anisotropic brain tissues was calculated from the measured magnetic flux density based on the linear relationship between the water diffusion tensor and the electrical conductivity tensor. Comparing the current density to the previous isotropic model, the anisotropic model clearly showed the differences between the brain tissues. This originates from the enhanced signals by the inherent conductivity contrast as well as the actual tissue condition resulting from the injected currents.

  20. Effects of different concentrations of pollen extract on brain tissues of Oncorhynchus mykiss

    Institute of Scientific and Technical Information of China (English)

    Mehmet Fuat Gulhan; Hasan Akgul; Taner Dastan; Sevgi Durna Dastan; Zeliha Selamoglu Talas

    2014-01-01

    Objective: To determine the antioxidant capacities of pollen extract applied at different concentrations on biochemical parameters in brain tissues of rainbow trouts. Methods:parameters in brain tissues of fish treated at various concentrations of the pollen extract (0.5, 2.5, 5, 10, 20 and 30 mg/L) for 96 h. The malondialdehyde levels, total antioxidant status, total oxidant status, oxidative stress index and amounts of total free sulfhydryl groups were analyzed in fish brain. Results:The effective concentration of pollen was determined with some biochemical treated compared to control group (P Conclusions: To apply the pollen to fish reduces the detrimental effects and modulates oxidative status via activating antioxidant defense systems at brain tissue. As a result, pollen can be added up to 10 mg/L to the medium of rainbow trout to improve health of fish.

  1. Brain uptake, pharmacokinetics, and tissue distribution in the rat of neurotoxic N-butylbenzenesulfonamide.

    Science.gov (United States)

    Kumar, Ganesh; Smith, Quentin R; Hokari, Mitsuhiko; Parepally, Jagan; Duncan, Mark W

    2007-06-01

    The pharmacokinetics, cerebrovascular permeability, and tissue distribution of the neurotoxic plasticizer N-butylbenzenesulfonamide (NBBS) were determined in rats. A stable isotope-labeled form ([(13)C(6)]NBBS) was used to circumvent ubiquitous contamination that was evident whenever the native form was measured. Plasticizer decline in plasma, following an iv dose of 1 mg/kg, was described by a triexponential decay function. NBBS was cleared from plasma at a rate of 25 ml/min/kg, and 24 h after administration, plasma concentrations represented 0.04% of the administered dose. These data suggest rapid elimination and uptake into tissue; however, NBBS was not accumulated by any of the tissues studied (i.e., liver, kidney, muscle, adipose tissue, and brain). Given the critical interest in NBBS neurotoxicity, the brain uptake of [(13)C(6)]NBBS was further explored in experiments using the in situ brain perfusion technique. During perfusion with protein-free saline for 15-30 s, the single-pass brain extraction for free [(13)C(6)]NBBS was very high (73-100%) with a unidirectional blood-brain barrier transfer constant (K(in)) of > 0.08 ml/s/g. No significant differences were found in [(13)C(6)]NBBS content among the measured brain regions. Plasma protein binding (70%) only slightly lowered the single-pass brain extraction to 48%. In summary, the results demonstrate that NBBS distributes rapidly to tissues, including brain. Though highly lipophilic with a Log octanol/water partition coefficient of 2.17 +/- 0.09, brain:blood ratios (2:1) for NBBS were consistent throughout the experimental duration, with little indication of accumulation. PMID:17369196

  2. Acute Supramaximal Exercise Increases the Brain Oxygenation in Relation to Cognitive Workload.

    Science.gov (United States)

    Bediz, Cem Seref; Oniz, Adile; Guducu, Cagdas; Ural Demirci, Enise; Ogut, Hilmi; Gunay, Erkan; Cetinkaya, Caner; Ozgoren, Murat

    2016-01-01

    Single bout of exercise can improve the performance on cognitive tasks. However, cognitive responses may be controversial due to different type, intensity, and duration of exercise. In addition, the mechanism of the effect of acute exercise on brain is still unclear. This study was aimed to investigate the effects of supramaximal exercise on cognitive tasks by means of brain oxygenation monitoring. The brain oxygenation of Prefrontal cortex (PFC) was measured on 35 healthy male volunteers via functional near infrared spectroscopy (fNIRS) system. Subjects performed 2-Back test before and after the supramaximal exercise wingate anerobic test (WAnT) lasting 30-s on cycle ergometer. The PFC oxygenation change evaluation revealed that PFC oxygenation rise during post-exercise 2-Back task was considerably higher than those in pre-exercise 2-Back task. In order to describe the relationship between oxygenation change and exercise performance, subjects were divided into two groups as high performers (HP) and low performers (LP) according to their peak power values (PP) obtained from the supramaximal test. The oxy-hemoglobin (oxy-Hb) values were compared between pre- and post-exercise conditions within subjects and also between subjects according to peak power. When performers were compared, in the HP group, the oxy-Hb values in post-exercise 2-Back test were significantly higher than those in pre-exercise 2-Back test. HP had significantly higher post-exercise oxy-Hb change (Δ) than those of LP. In addition, PP of the total group were significantly correlated with Δoxy-Hb.The key findings of the present study revealed that acute supramaximal exercise has an impact on the brain oxygenation during a cognitive task. Also, the higher the anerobic PP describes the larger the oxy-Hb response in post-exercise cognitive task. The current study also demonstrated a significant correlation between peak power (exercise load) and post-exercise hemodynamic responses (oxy-, deoxy- and

  3. Acute supramaximal exercise increases the brain oxygenation in relation to cognitive workload

    Directory of Open Access Journals (Sweden)

    Cem Seref Bediz

    2016-04-01

    Full Text Available Single bout of exercise can improve the performance on cognitive tasks. However, cognitive responses may be controversial due to different type, intensity, and duration of exercise. In addition, the mechanism of the effect of acute exercise on brain is still unclear. This study was aimed to investigate the effects of supramaximal exercise on cognitive tasks by means of brain oxygenation monitoring. The brain oxygenation of Prefrontal cortex (PFC was measured on 35 healthy male volunteers via functional Near Infrared Spectroscopy (fNIRS system. Subjects performed 2-Back test before and after the supramaximal exercise (Wingate Anaerobic Test lasting 30-s on cycle ergometer. The PFC oxygenation change evaluation revealed that PFC oxygenation rise during post-exercise 2-Back task was considerably higher than those in pre-exercise 2-Back task. In order to describe the relationship between oxygenation change and exercise performance, subjects were divided into two groups as high performers (HP and low performers (LP according to their peak power values (PP obtained from the supramaximal test. The oxy-hemoglobin (oxy-Hb values were compared between pre- and post-exercise conditions within subjects and also between subjects according to peak power. When performers were compared, in the HP group, the oxy-Hb values in post-exercise 2-Back test were significantly higher than those in pre-exercise 2-Back test. HP had significantly higher post-exercise oxy-Hb change (Δ than those of LP. In addition, peak power values of the total group were significantly correlated with Δoxy-Hb. The key findings of the present study revealed that acute supramaximal exercise has an impact on the brain oxygenation during a cognitive task. Also, the higher the anaerobic PP describes the larger the oxy-Hb response in post-exercise cognitive task. The current study also demonstrated a significant correlation between peak power (exercise load and post-exercise hemodynamic

  4. Prostacyclin infusion may prevent secondary damage in pericontusional brain tissue

    DEFF Research Database (Denmark)

    Reinstrup, Peter; Nordström, Carl-Henrik

    2011-01-01

    Prostacyclin is a potent vasodilator, inhibitor of leukocyte adhesion, and platelet aggregation, and has been suggested as therapy for cerebral ischemia. A case of focal traumatic brain lesion that was monitored using intracerebral microdialysis, and bedside analysis and display is reported here........ When biochemical signs of cerebral ischemia progressed, i.v. infusion of prostacyclin was started....

  5. Automatic Analysis of Brain Tissue and Structural Connectivity in MRI

    NARCIS (Netherlands)

    R. de Boer (Renske)

    2011-01-01

    textabstractStudies of the brain using magnetic resonance imaging (MRI) can provide insights in physiology and pathology that can eventually aid clinical diagnosis and therapy monitoring. MRI data acquired in these studies can be difficult, as well as laborious, to interpret and analyze by human obs

  6. A protein homeostasis signature in healthy brains recapitulates tissue vulnerability to Alzheimer's disease.

    Science.gov (United States)

    Freer, Rosie; Sormanni, Pietro; Vecchi, Giulia; Ciryam, Prajwal; Dobson, Christopher M; Vendruscolo, Michele

    2016-08-01

    In Alzheimer's disease, aggregates of Aβ and tau in amyloid plaques and neurofibrillary tangles spread progressively across brain tissues following a characteristic pattern, implying a tissue-specific vulnerability to the disease. We report a transcriptional analysis of healthy brains and identify an expression signature that predicts-at ages well before the typical onset-the tissue-specific progression of the disease. We obtain this result by finding a quantitative correlation between the histopathological staging of the disease and the expression patterns of the proteins that coaggregate in amyloid plaques and neurofibrillary tangles, together with those of the protein homeostasis components that regulate Aβ and tau. Because this expression signature is evident in healthy brains, our analysis provides an explanatory link between a tissue-specific environmental risk of protein aggregation and a corresponding vulnerability to Alzheimer's disease. PMID:27532054

  7. Tissue oxygenation as a target for goal-directed therapy in high-risk surgery : a pilot study

    NARCIS (Netherlands)

    van Beest, Paul A.; Vos, Jaap Jan; Poterman, Marieke; Kalmar, Alain F.; Scheeren, Thomas W. L.

    2014-01-01

    Background: Tissue hypoperfusion occurs frequently during surgery and may contribute to postoperative organ dysfunction. There is a need for perioperative treatment protocols aiming at improving tissue oxygenation (StO(2)). We hypothesised that intra-operative optimisation of StO(2) improves tissue

  8. Analytic Models of Oxygen and Nutrient Diffusion, Metabolism Dynamics, and Architecture Optimization in Three-Dimensional Tissue Constructs with Applications and Insights in Cerebral Organoids.

    Science.gov (United States)

    McMurtrey, Richard J

    2016-03-01

    Diffusion models are important in tissue engineering as they enable an understanding of gas, nutrient, and signaling molecule delivery to cells in cell cultures and tissue constructs. As three-dimensional (3D) tissue constructs become larger, more intricate, and more clinically applicable, it will be essential to understand internal dynamics and signaling molecule concentrations throughout the tissue and whether cells are receiving appropriate nutrient delivery. Diffusion characteristics present a significant limitation in many engineered tissues, particularly for avascular tissues and for cells whose viability, differentiation, or function are affected by concentrations of oxygen and nutrients. This article seeks to provide novel analytic solutions for certain cases of steady-state and nonsteady-state diffusion and metabolism in basic 3D construct designs (planar, cylindrical, and spherical forms), solutions that would otherwise require mathematical approximations achieved through numerical methods. This model is applied to cerebral organoids, where it is shown that limitations in diffusion and organoid size can be partially overcome by localizing metabolically active cells to an outer layer in a sphere, a regionalization process that is known to occur through neuroglial precursor migration both in organoids and in early brain development. The given prototypical solutions include a review of metabolic information for many cell types and can be broadly applied to many forms of tissue constructs. This work enables researchers to model oxygen and nutrient delivery to cells, predict cell viability, study dynamics of mass transport in 3D tissue constructs, design constructs with improved diffusion capabilities, and accurately control molecular concentrations in tissue constructs that may be used in studying models of development and disease or for conditioning cells to enhance survival after insults like ischemia or implantation into the body, thereby providing a

  9. Apoptosis-related protein expression in rabbits with blast brain injury following early hyperbaric oxygen therapy

    Institute of Scientific and Technical Information of China (English)

    Shaonian Xu; Jiachuan Liu; Yongming Zhang; Chunlin Wang; Jinbiao Wang; Yanyan Yang; Jian Huo; Wenjiang Sun

    2012-01-01

    We treated detonator-explosion-induced craniocerebral injury in rabbits with hyperbaric oxygen 1-24 hours post-injury. Expression of the apoptosis-regulating protein cytochrome c, the pro-apoptotic protein Bax and the apoptosis marker caspase-3 in the tissues surrounding the area of injury was significantly reduced, while that of the anti-apoptotic protein Bcl-2 was significantly increased. Our findings indicate that the curative effects of early hyperbaric oxygen on cortical cell apoptosis is associated with suppression of cytochrome c release from mitochondria. This mechanism underlies the observed reduction in Bax expression and upregulation of Bcl-2 expression.

  10. Blood flow and oxygenation in peritendinous tissue and calf muscle during dynamic exercise in humans

    DEFF Research Database (Denmark)

    Boushel, Robert Christopher; Langberg, H; Green, Sara Marie Ehrenreich;

    2000-01-01

    1. Circulation around tendons may act as a shunt for muscle during exercise. The perfusion and oxygenation of Achilles' peritendinous tissue was measured in parallel with that of calf muscle during exercise to determine (1) whether blood flow is restricted in peritendinous tissue during exercise...... with a rise in leg vascular conductance and microvascular haemoglobin volume, despite elevated systemic vascular resistance. 4. The parallel rise in calf muscle and peritendinous blood flow and fall in O2 saturation during exercise indicate that blood flow is coupled to oxidative metabolism in both tissue...... by dye dilution, arterial pressure by an arterial catheter-transducer, and muscle and peritendinous O2 saturation by spatially resolved spectroscopy (SRS). 3. Calf blood flow rose 20-fold with exercise, reaching 44 +/- 7 ml (100 g)-1 min-1 (mean +/- s.e.m. ) at 9 W, while Achilles' peritendinous flow...

  11. The ethics of extracorporeal membrane oxygenation in brain-dead potential organ donors.

    Science.gov (United States)

    Dalle Ave, Anne L; Gardiner, Dale; Shaw, David M

    2016-05-01

    Organ-preserving extracorporeal membrane oxygenation (OP-ECMO) is defined as the use of extracorporeal support for the primary purpose of preserving organs for transplantation, rather than to save the patient's life. This paper discusses the ethics of using OP-ECMO in donation after brain determination of death (DBDD) to avoid the loss of organs for transplantation. We review case reports in the literature and analyze the ethical issues raised. We conclude that there is little additional ethical concern in continuing OP-ECMO in patients already on ECMO if they become brain dead. The implementation of OP-ECMO in hemodynamically unstable brain-dead patients is ethically permissible in certain clinical situations but requires specific consent from relatives if the patient's wish to donate is not clear. If no evidence of a patient's wish to donate is available, OP-ECMO is not recommended. In countries with presumed consent legislation, failure to opt out should be considered as a positive wish to donate. If a patient is not-yet brain-dead or is undergoing testing for brain death, OP-ECMO is not recommended. Further research on OP-ECMO is needed to better understand the attitudes of professionals, families, and lay people to ensure agreement on key ethical issues. PMID:26987689

  12. Differential production of reactive oxygen species in distinct brain regions of hypoglycemic mice.

    Science.gov (United States)

    Amador-Alvarado, Leticia; Montiel, Teresa; Massieu, Lourdes

    2014-09-01

    Hypoglycemia is a serious complication of insulin therapy in patients suffering from type 1 Diabetes Mellitus. Severe hypoglycemia leading to coma (isoelectricity) induces massive neuronal death in vulnerable brain regions such as the hippocampus, the striatum and the cerebral cortex. It has been suggested that the production of reactive oxygen species (ROS) and oxidative stress is involved in hypoglycemic brain damage, and that ROS generation is stimulated by glucose reintroduction (GR) after the hypoglycemic coma. However, the distribution of ROS in discrete brain regions has not been studied in detail. Using the oxidation sensitive marker dihydroethidium (DHE) we have investigated the distribution of ROS in different regions of the mouse brain during prolonged severe hypoglycemia without isoelectricity, as well as the effect of GR on ROS levels. Results show that ROS generation increases in the hippocampus, the cerebral cortex and the striatum after prolonged severe hypoglycemia before the coma. The hippocampus showed the largest increases in ROS levels. GR further stimulated ROS production in the hippocampus and the striatum while in the cerebral cortex, only the somatosensory and parietal areas were significantly affected by GR. Results suggest that ROS are differentially produced during the hypoglycemic insult and that a different response to GR is present among distinct brain regions.

  13. Dynamic effects of point source electroporation on the rat brain tissue.

    Science.gov (United States)

    Sharabi, Shirley; Last, David; Guez, David; Daniels, Dianne; Hjouj, Mohammad Ibrahim; Salomon, Sharona; Maor, Elad; Mardor, Yael

    2014-10-01

    In spite of aggressive therapy, existing treatments offer poor prognosis for glioblastoma multiforme due to tumor infiltration into the surrounding brain as well as poor blood-brain barrier penetration of most therapeutic agents. In this paper we present a novel approach for a minimally invasive treatment and a non-invasive response assessment methodology consisting of applying intracranial point-source electroporation and assessing treatment effect volumes using magnetic resonance imaging. Using a unique setup of a single intracranial electrode and an external surface electrode we treated rats' brains with various electroporation protocols and applied magnetic resonance imaging to study the dependence of the physiological effects on electroporation treatment parameters. The extent of blood-brain barrier disruption and later volumes of permanent brain tissue damage were found to correlate significantly with the treatment voltages (r(2)=0.99, pelectroporation when planning a treatment for brain tumors.

  14. O2 supplementation to secure the near-infrared spectroscopy determined brain and muscle oxygenation in vascular surgical patients

    DEFF Research Database (Denmark)

    Rokamp, Kim Z; Secher, Niels H; Eiberg, Jonas;

    2014-01-01

    in rScO2 correlated to cardiac output and cardiac stroke volume (coefficient of contingence = 0.36; P = 0.0003) rather to a change in mean arterial pressure and for five patients rScO2 was reduced to below 50%. We conclude that (i) increased oxygen delivery enhances tissue oxygenation, (ii) oxygen...... oxygenation was determined by INVOS 5100C. Preoxygenation increased rScO2 (from 65 ± 8 to 72 ± 9%; P

  15. Effect of oxygen breathing on micro oxygen bubbles in nitrogen-depleted rat adipose tissue at sea level and 25 kPa altitude exposures.

    Science.gov (United States)

    Randsoe, Thomas; Hyldegaard, Ole

    2012-08-01

    The standard treatment of altitude decompression sickness (aDCS) caused by nitrogen bubble formation is oxygen breathing and recompression. However, micro air bubbles (containing 79% nitrogen), injected into adipose tissue, grow and stabilize at 25 kPa regardless of continued oxygen breathing and the tissue nitrogen pressure. To quantify the contribution of oxygen to bubble growth at altitude, micro oxygen bubbles (containing 0% nitrogen) were injected into the adipose tissue of rats depleted from nitrogen by means of preoxygenation (fraction of inspired oxygen = 1.0; 100%) and the bubbles studied at 101.3 kPa (sea level) or at 25 kPa altitude exposures during continued oxygen breathing. In keeping with previous observations and bubble kinetic models, we hypothesize that oxygen breathing may contribute to oxygen bubble growth at altitude. Anesthetized rats were exposed to 3 h of oxygen prebreathing at 101.3 kPa (sea level). Micro oxygen bubbles of 500-800 nl were then injected into the exposed abdominal adipose tissue. The oxygen bubbles were studied for up to 3.5 h during continued oxygen breathing at either 101.3 or 25 kPa ambient pressures. At 101.3 kPa, all bubbles shrank consistently until they disappeared from view at a net disappearance rate (0.02 mm(2) × min(-1)) significantly faster than for similar bubbles at 25 kPa altitude (0.01 mm(2) × min(-1)). At 25 kPa, most bubbles initially grew for 2-40 min, after which they shrank and disappeared. Four bubbles did not disappear while at 25 kPa. The results support bubble kinetic models based on Fick's first law of diffusion, Boyles law, and the oxygen window effect, predicting that oxygen contributes more to bubble volume and growth during hypobaric conditions. As the effect of oxygen increases, the lower the ambient pressure. The results indicate that recompression is instrumental in the treatment of aDCS.

  16. Frequency-dependent viscoelastic parameters of mouse brain tissue estimated by MR elastography

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, E H; Bayly, P V [Department of Mechanical Engineering and Materials Science, Washington University in St Louis, 1 Brookings Drive, Campus Box 1185, Saint Louis, MO 63130 (United States); Garbow, J R, E-mail: clayton@wustl.edu, E-mail: garbow@wustl.edu, E-mail: pvb@wustl.edu [Biomedical Magnetic Resonance Laboratory, Department of Radiology, Washington University in St Louis, 4525 Scott Avenue, Campus Box 8227, Saint Louis, MO 63110 (United States)

    2011-04-21

    Viscoelastic properties of mouse brain tissue were estimated non-invasively, in vivo, using magnetic resonance elastography (MRE) at 4.7 T to measure the dispersive properties of induced shear waves. Key features of this study include (i) the development and application of a novel MR-compatible actuation system which transmits vibratory motion into the brain through an incisor bar, and (ii) the investigation of the mechanical properties of brain tissue over a 1200 Hz bandwidth from 600-1800 Hz. Displacement fields due to propagating shear waves were measured during continuous, harmonic excitation of the skull. This protocol enabled characterization of the true steady-state patterns of shear wave propagation. Analysis of displacement fields obtained at different frequencies indicates that the viscoelastic properties of mouse brain tissue depend strongly on frequency. The average storage modulus (G') increased from approximately 1.6 to 8 kPa over this range; average loss modulus (G'') increased from approximately 1 to 3 kPa. Both moduli were well approximated by a power-law relationship over this frequency range. MRE may be a valuable addition to studies of disease in murine models, and to pre-clinical evaluations of therapies. Quantitative measurements of the viscoelastic parameters of brain tissue at high frequencies are also valuable for modeling and simulation of traumatic brain injury.

  17. Optimal Gaussian Mixture Models of Tissue Intensities in Brain MRI of Patients with Multiple-Sclerosis

    Science.gov (United States)

    Xiao, Yiming; Shah, Mohak; Francis, Simon; Arnold, Douglas L.; Arbel, Tal; Collins, D. Louis

    Brain tissue segmentation is important in studying markers in human brain Magnetic Resonance Images (MRI) of patients with diseases such as Multiple Sclerosis (MS). Parametric segmentation approaches typically assume unimodal Gaussian distributions on MRI intensities of individual tissue classes, even in applications on multi-spectral images. However, this assumption has not been rigorously verified especially in the context of MS. In this work, we evaluate the local MRI intensities of both healthy and diseased brain tissues of 21 multi-spectral MRIs (63 volumes in total) of MS patients for adherence to this assumption. We show that the tissue intensities are not uniform across the brain and vary across (anatomical) regions of the brain. Consequently, we show that Gaussian mixtures can better model the multi-spectral intensities. We utilize an Expectation Maximization (EM) based approach to learn the models along with a symmetric Jeffreys divergence criterion to study differences in intensity distributions. The effects of these findings are also empirically verified on automatic segmentation of brains with MS.

  18. Haloperidol imprinted polymer: preparation, evaluation, and application for drug assay in brain tissue.

    Science.gov (United States)

    Rahmani, Aboubakr; Mohammadpour, Amir Hooshang; Sahebnasagh, Adeleh; Mohajeri, Seyed Ahmad

    2014-11-01

    Several molecularly imprinted polymers (MIPs) were prepared in the present work, and their binding properties were evaluated in comparison with a nonimprinted polymer (NIP). An optimized MIP was selected and applied for selective extraction and analysis of haloperidol in rabbit brain tissue. A molecularly imprinted solid-phase extraction (MISPE) method was developed for cleanup and preconcentration of haloperidol in brain samples before HPLC-UV analysis. Selectivity of the MISPE procedure was investigated using haloperidol and some structurally different drugs with similar polarity that could exist simultaneously in brain tissue. The extraction and analytical process was calibrated in the range of 0.05-10 ppm. The recovery of haloperidol in this MISPE process was calculated between 79.9 and 90.4%. The limit of detection (LOD) and the limit of quantification (LOQ) of the assay were 0.008 and 0.05 ppm, respectively. Intraday precision and interday precision values for haloperidol analysis were less than 5.86 and 7.63%, respectively. The MISPE method could effectively extract and concentrate haloperidol from brain tissue in the presence of clozapine and imipramine. Finally, the imprinted polymer was successfully applied for the determination of haloperidol in a real rabbit brain sample after administration of a toxic dose. Therefore, the proposed MISPE method could be applied in the extraction and preconcentration before HPLC-UV analysis of haloperidol in rabbit brain tissue.

  19. Frequency-dependent viscoelastic parameters of mouse brain tissue estimated by MR elastography

    International Nuclear Information System (INIS)

    Viscoelastic properties of mouse brain tissue were estimated non-invasively, in vivo, using magnetic resonance elastography (MRE) at 4.7 T to measure the dispersive properties of induced shear waves. Key features of this study include (i) the development and application of a novel MR-compatible actuation system which transmits vibratory motion into the brain through an incisor bar, and (ii) the investigation of the mechanical properties of brain tissue over a 1200 Hz bandwidth from 600-1800 Hz. Displacement fields due to propagating shear waves were measured during continuous, harmonic excitation of the skull. This protocol enabled characterization of the true steady-state patterns of shear wave propagation. Analysis of displacement fields obtained at different frequencies indicates that the viscoelastic properties of mouse brain tissue depend strongly on frequency. The average storage modulus (G') increased from approximately 1.6 to 8 kPa over this range; average loss modulus (G'') increased from approximately 1 to 3 kPa. Both moduli were well approximated by a power-law relationship over this frequency range. MRE may be a valuable addition to studies of disease in murine models, and to pre-clinical evaluations of therapies. Quantitative measurements of the viscoelastic parameters of brain tissue at high frequencies are also valuable for modeling and simulation of traumatic brain injury.

  20. Cell and tissue kinetics of the subependymal layer in mouse brain following heavy charged particle irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Manley, N.B.; Fabrikant, J.I.; Alpen, E.L.

    1988-12-01

    The following studies investigate the cellular response and cell population kinetics of the subependymal layer in the mouse brain exposed to heavy charged particle irradiation. Partial brain irradiation with helium and neon ions was confined to one cortex of the brain. Both the irradiated and the unirradiated contralateral cortex showed similar disturbances of the cell and tissue kinetics in the subependymal layers. The irradiated hemisphere exhibited histological damage, whereas the unirradiated side appeared normal histologically. This study concerns the cell population and cell cycle kinetics of the subependymal layer in the mouse brain, and the effects of charged particle irradiations on this cell population. Quantitative high resolution autoradiography was used to study the kinetic parameters in this cell layer. This study should help in understanding the effects of these high-energy heavy ions on normal mammalian brain tissue. The response of the mammalian brain exposure to charged particle ionizing radiation may be extremely variable. It varies from minimal physiological changes to overt tissue necrosis depending on a number of factors such as: the administered dose, dose-rate, the volume of the irradiated tissue, and the biological end-point being examined.

  1. Near-infrared oxymeter biosensor prototype for non-invasive in vivo analysis of rat brain oxygenation: effects of drugs of abuse

    Science.gov (United States)

    Crespi, F.; Donini, M.; Bandera, A.; Congestri, F.; Formenti, F.; Sonntag, V.; Heidbreder, C.; Rovati, L.

    2006-07-01

    The feasibility of non-invasive analysis of brain activities was studied in the attempt to overcome the major limitation of actual in vivo methodologies, i.e. invasiveness. Optic fibre probes were used as the optical head of a novel, highly sensitive near-infrared continuous wave spectroscopy (CW-NIR) instrument. This prototype was designed for non-invasive analysis of the two main forms of haemoglobin: oxy-haemoglobin (HbO2) and deoxy-haemoglobin (Hb), chromophores present in biological tissues. It was tested in peripheral tissue (human gastrocnemius muscle) and then reset to perform the measurement on rat brain. In animal studies, the optical head was firmly placed using stereotaxic apparatus upon the sagittal line of the head of anaesthetized adult rats, without any surgery. Then pharmacological treatments with saline (300 µl s.c.) amphetamine (2 mg kg-1) or nicotine (0.4 mg kg-1) were performed. Within 10-20 min amphetamine substantially increased HbO2 and reduced Hb control levels. Nicotine produced a rapid initial increase followed by a decrease in HbO2. In contrast to amphetamine, nicotine treatment also reduced Hb and blood volume. These results support the capacity of our CW-NIR prototype to measure non-invasively HbO2 and Hb levels in the rat brain, that are markers of the degree of tissue oxygenation, thus providing an index of blood levels and therefore of brain metabolism.

  2. Microsensors for in vivo Measurement of Glutamate in Brain Tissue

    OpenAIRE

    Miranda van der Zeyden; Oldenziel, Weite H.; Cremers, Thomas I.F.H.; Westerink, Ben H.C.; Si Qin

    2008-01-01

    Several immobilized enzyme-based electrochemical biosensors for glutamate detection have been developed over the last decade. In this review, we compare first and second generation sensors. Structures, working mechanisms, interference prevention, in vitro detection characteristics and in vivo performance are summarized here for those sensors that have successfully detected brain glutamate in vivo. In brief, first generation sensors have a simpler structure and are faster in glutamate detectio...

  3. Effect of xinmailong on metabolism of oxygen free radicals and content of lipofuscin in brain and hepatic tissues%心脉龙干预后氧自由基代谢及脑、肝组织脂褐质含量的变化

    Institute of Scientific and Technical Information of China (English)

    吴建新; 钮荣祥; 黄秀群; 田昆仑; 董丛丽

    2006-01-01

    dismutase (SOD) and glutathione peroxidase (GSH-Px) in serum, content of malondialdehyde (MDA) in brain tissue and content of lipofuscin in cerebral and hepatic tissue were measured according to introduction of kits.MAIN OUTCOME MEASURES: ① Activities of CAT, SOD and GSHPx in serum; ② content of MDA in brain tissue and contents of lipofuscin in cerebral and hepatic tissues.RFSULTS: A total of 40 animals were involved in the final analysis without any loss. ① Activities of CAT, SOD and GSH-Px in serum of mice were lower in aging control group than those in young control group; however,activities of CAT, SOD and GSH-Px in serum of mice were increased in the two XML dosage groups, and there was significant difference from those in aging control group (P < 0.05 or P < 0.01). ② Content of MDA in brain tissue and contents of lipofuscin in cerebral and hepatic tissues of mice in aging control group were higher than those of mice in young control group, but those in the two dosage groups were decreased, which was significant difference from those of mice in aging control group (P < 0.01). However, there was no significant difference between the two dosage groups.CONCLUSION: XML has an effect on anti-aging through improving metabolism of free radicals.

  4. Static jaw collimation settings to minimize radiation dose to normal brain tissue during stereotactic radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Han, Eun Young, E-mail: eyhan@uams.edu [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States); Zhang Xin; Yan Yulong; Sharma, Sunil; Penagaricano, Jose [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States); Moros, Eduardo [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL (United States); Corry, Peter [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States)

    2012-01-01

    At University of Arkansas for Medical Sciences (UAMS) intracranial stereotactic radiosurgery (SRS) is performed by using a linear accelerator with an add-on micromultileaf collimator (mMLC). In our clinical setting, static jaws are automatically adapted to the furthest edge of the mMLC-defined segments with 2-mm (X jaw) and 5-mm (Y jaw) margin and the same jaw values are applied for all beam angles in the treatment planning system. This additional field gap between the static jaws and the mMLC allows additional radiation dose to normal brain tissue. Because a radiosurgery procedure consists of a single high dose to the planning target volume (PTV), reduction of unnecessary dose to normal brain tissue near the PTV is important, particularly for pediatric patients whose brains are still developing or when a critical organ, such as the optic chiasm, is near the PTV. The purpose of this study was to minimize dose to normal brain tissue by allowing minimal static jaw margin around the mMLC-defined fields and different static jaw values for each beam angle or arc. Dose output factors were measured with various static jaw margins and the results were compared with calculated doses in the treatment planning system. Ten patient plans were randomly selected and recalculated with zero static jaw margins without changing other parameters. Changes of PTV coverage, mean dose to predefined normal brain tissue volume adjacent to PTV, and monitor units were compared. It was found that the dose output percentage difference varied from 4.9-1.3% for the maximum static jaw opening vs. static jaw with zero margins. The mean dose to normal brain tissue at risk adjacent to the PTV was reduced by an average of 1.9%, with negligible PTV coverage loss. This dose reduction strategy may be meaningful in terms of late effects of radiation, particularly in pediatric patients. This study generated clinical knowledge and tools to consistently minimize dose to normal brain tissue.

  5. Changes in Lecithin Concentration in the Human Brain Tissue in Some Neurodegenerative Conditions

    International Nuclear Information System (INIS)

    As a consequence of a possible increase in oxidative stress or deterioration of nerve cells during aging, in some states neurodegeneration was demonstrated by multiple biochemical deficiency, especially deficiency of cholesterol and lecithin in brain regions. The aim of this study was to determine the changes in the concentration of lecithin in different regions of brain tissue (MC - motor cortex, NC - nucleus caudates, GT - temporal gyrus) dissected postmortem from people with senile dementia of Alzheimer's type (SDAT), and persons with Parkinson's disease (PD) as compared to people who died without these diseases (C). Spectrophotometric determination of lecithin in 18 postmortem brain tissue regions collected from of 12 persons with SDAT, in 11 postmortem brain tissue regions of 8 persons with PD and in 18 postmortem brain tissue regions of 8 control persons, was performed by enzymatic method. The content of lecithin in MC: 14.4 mg/g fresh tissue (f.t.) and GT: 13.1 mg/g (f.t.) for SDAT was significantly reduced (p < 0.01) by about 30 %, compared to control where there was: 21.6 mg/g (f.t.) in MC and 18.3 mg/g (f.t.) in the GT estimated. In all regions of the brain of PD patients, the content of lecithin was decreased by about 12 % compared to control, but without statistical significance. These results suggest that changes in the content of lecithin in these regions of brain tissue might affect the changes in the membrane potential and cell degeneration. (author)

  6. Trace element determinations in brain tissues from normal and clinically demented individuals

    Energy Technology Data Exchange (ETDEWEB)

    Saiki, Mitiko; Genezini, Frederico A., E-mail: mitiko@ipen.br, E-mail: fredzini@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro do Reator de Pesquisas; Leite, Renata E.P.; Grinberg, Lea T.; Ferretti, Renata E.L.; Suemoto, Claudia; Pasqualucci, Carlos A.; Jacob-Filho, Wilson, E-mail: renataleite@usp.br, E-mail: lea@grinberg.com.br, E-mail: reloah@usp.br, E-mail: farfel@usp.br, E-mail: csuemoto@gmail.com, E-mail: cpasqua@usp.br, E-mail: wijac@usp.br [Universidade de Sao Paulo (FM/USP), Sao Paulo, SP (Brazil). Fac. de Medicina

    2013-07-01

    Studies on trace element levels in human brains under normal and pathological conditions have indicated a possible correlation between some trace element concentrations and neurodegenerative diseases. In this study, analysis of brain tissues was carried out to investigate if there are any differences in elemental concentrations between brain tissues from a normal population above 50 years of age presenting Clinical Dementia Rating (CDR) equal to zero (CDR=0) and that cognitively affected population ( CDR=3). The tissues were dissected, ground, freeze-dried and then analyzed by instrumental neutron activation analysis. Samples and elemental standards were irradiated in a neutron flux at the IEA-R1 nuclear research reactor for Br, Fe, K, Na, Rb, Se and Zn determinations. The induced gamma ray activities were measured using a hyperpure Ge detector coupled to a gamma ray spectrometer. The one-way ANOVA test (p< 0.05) was used to compare the results. All the elements determined in the hippocampus brain region presented differences between the groups presenting CDR=0 and CDR=3. In the case of frontal region only the elements Na, Rb and Zn showed differences between these two groups. These findings proved the correlation between elemental levels present in brain tissues neurodegenerative diseases. Biological standard reference materials SRM 1566b Oyster Tissue and SRM 1577b Bovine Liver analyzed for quality control indicated good accuracy and precision of the results. (author)

  7. Trace element determinations in brain tissues from normal and clinically demented individuals

    International Nuclear Information System (INIS)

    Studies on trace element levels in human brains under normal and pathological conditions have indicated a possible correlation between some trace element concentrations and neurodegenerative diseases. In this study, analysis of brain tissues was carried out to investigate if there are any differences in elemental concentrations between brain tissues from a normal population above 50 years of age presenting Clinical Dementia Rating (CDR) equal to zero (CDR=0) and that cognitively affected population ( CDR=3). The tissues were dissected, ground, freeze-dried and then analyzed by instrumental neutron activation analysis. Samples and elemental standards were irradiated in a neutron flux at the IEA-R1 nuclear research reactor for Br, Fe, K, Na, Rb, Se and Zn determinations. The induced gamma ray activities were measured using a hyperpure Ge detector coupled to a gamma ray spectrometer. The one-way ANOVA test (p< 0.05) was used to compare the results. All the elements determined in the hippocampus brain region presented differences between the groups presenting CDR=0 and CDR=3. In the case of frontal region only the elements Na, Rb and Zn showed differences between these two groups. These findings proved the correlation between elemental levels present in brain tissues neurodegenerative diseases. Biological standard reference materials SRM 1566b Oyster Tissue and SRM 1577b Bovine Liver analyzed for quality control indicated good accuracy and precision of the results. (author)

  8. Cutaneous Heterotopic Brain Tissue (Neuroglial Choristoma) with Dysplastic Features in a Kitten.

    Science.gov (United States)

    Ramírez, G A; Ressel, L; Altimira, J; Vilafranca, M

    2016-07-01

    A 3-month-old, male European shorthair kitten exhibited an ill-defined, soft mass on the skin of the frontal head, which was present since birth. The surgically resected tissue was representative of a discrete dermal and subcutaneous mass comprising islands of neurons, glial and meningothelial elements, sometimes atypical or dysplastic, separated by dense collagenous connective tissue. There was no evident connection between this tissue and the brain. Immunohistochemical examination confirmed the presence of neurons and a pleocellular glial population, supporting a diagnosis of cutaneous neuroglial choristoma believed to be secondary to sequestered (resolved) meningoencephalocoele. Ectopic brain tissue is very rare in small animals. Some atypical features displayed by this tissue may be misdiagnosed as neoplasia. Communication between surgeon and pathologist to clarify the relationship of the lesion to surrounding structures is helpful to avoid misdiagnosis. PMID:27324745

  9. The influence of an unilateral carotid artery stenosis on brain oxygenation.

    Science.gov (United States)

    Köppl, T; Schneider, M; Pohl, U; Wohlmuth, B

    2014-07-01

    We study the impact of varying degrees of unilateral stenoses of an carotid artery on pulsatile blood flow and oxygen transport from the heart to the brain. For the numerical simulation a model reduction approach is used involving non-linear 1-D transport equation systems, linear 1-D transport equations and 0-D models. The haemodynamic effects of vessels beyond the outflow boundaries of the 1-D models are accounted for using a 0-D lumped three element windkessel model. At the cerebral outflow boundaries the 0-D windkessel model is extended by metabolic autoregulation, based on the cerebral oxygen supply. Additionally lumped parameter models are applied to incorporate the impact of the carotid stenosis. Our model suggests that for a severe unilateral stenosis in the right carotid artery the partial pressure of oxygen in the brain area at risk can only be restored, if the corresponding cerebral resistance is significantly decreased and if the circle of Willis (CoW) is complete. PMID:24780755

  10. Plasma jet-induced tissue oxygenation: potentialities for new therapeutic strategies

    Science.gov (United States)

    Collet, G.; Robert, E.; Lenoir, A.; Vandamme, M.; Darny, T.; Dozias, S.; Kieda, C.; Pouvesle, J. M.

    2014-02-01

    The lack of oxygen is a major reason for the resistance of tumor cells to treatments such as radiotherapies. A large number of recent publications on non-thermal plasma applications in medicine report cell behavior modifications and modulation of soluble factors. This in vivo study tested whether such modifications can lead to vascular changes in response to plasma application. Two in situ optical-based methods were used simultaneously, in real time, to assess the effect of non-thermal plasma on tissue vasculature. Tissue oxygen partial pressure (pO2) was measured using a time-resolved luminescence-based optical probe, and the microvascular erythrocyte flow was determined by laser Doppler flowmetry. When plasma treatment was applied on mouse skin, a rapid pO2 increase (up to 4 times) was subcutaneously measured and correlated with blood flow improvement. Such short duration, i.e. 5 min, plasma-induced effects were shown to be locally restricted to the treated area and lasted over 120 min. Further investigations should elucidate the molecular mechanisms of these processes. However, improvement of oxygenation and perfusion open new opportunities for tumor treatments in combination with radiotherapy, and for tumor blood vessel normalization based strategies.

  11. Expression of inducible nitric oxide synthase in the brain tissue of rats at preoxygenation, hypoxia/reoxygenation

    Institute of Scientific and Technical Information of China (English)

    Hongzhi Chen; Lu Li; Hong Zhao

    2006-01-01

    BACKGROUND: The disorder of the respiratory and circulation system during the anesthesia and operation often can lead to severe hypoxia. Preoxygenation is a conventional therapy for treatment of hypoxia.OBJECTIVE: To observe the change in the expression of inducible nitric oxide synthase (iNOS), I.e. Brain tissue injury degree, in cerebral cortex of rats after hypoxia/reoxygenation under the condition of different levels of preoxygenation.DESIGN: Randomized controlled animal experiment.SETTING: Department of Anesthesiology and Central Laboratory, Shengjing Hospital Affiliated to China Medical University.MATERTALS: This experiment was carried out in the laboratory of Shengjing Hospital Affiliated to China Medical University from March 2003 to March 2004. Seventy-two male Wistar rats, weighing from 250 to 300 g,were provided by the Animal Experimental Room of Shengjing Hospital of China Medical University [License No. SYXK (Liao) 2003-0019]. Seventy-two rats were randomized into 3 groups: preoxygenation group, hypoxia group and reoxygentation group. Each group was divided into 4 subgroups, 6 rats in each subgroup.METHODS: 0.21, 0.50, 0.75 and 0.98 volume fraction of oxygen was given to 4 subgroups of preoxygenation group respectively. The rats in each subgroup of hypoxia group inhaled oxygen for 30 minutes according to the method of preoxygenation. Then, nitrogen gas replaced oxygen and was pumped into the cabin, and the volume fraction of oxygen was decreased to be 0.05 within 20 minutes. The rats in each subgroup of reoxygenation group were treated with the experimental methods of preoxygenation and hypoxia separately,then they were moved into the wide mouthed bottle with two-air-duct rubber stopper. Finally, oxygen was pumped and the volume fraction of oxygen reached over 0.98 within 20 minutes. After 24 hours, all the surviving rats were killed by decapitation. Cerebral tissue was sliced and stained by haematoxylin-eosin and then enveloped. Brain tissue injury

  12. Adaptive online learning based tissue segmentation of MR brain images

    NARCIS (Netherlands)

    Damkat, C.

    2007-01-01

    The aging population in the European Union and the US has increased the importance of research in neurodegenerative diseases. Imaging plays an essential role in this endeavor by providing insight to the intricate cellular and inter-cellular processes in living tissues that will otherwise be difficul

  13. Effect of oxygen and heliox breathing on air bubbles in adipose tissue during 25-kPa altitude exposures

    DEFF Research Database (Denmark)

    Randsoe, T.; Kvist, T.M.; Hyldegaard, O.

    2008-01-01

    and heliox breathing. Preoxygenation enhanced bubble disappearance compared with oxygen and heliox breathing but did not prevent bubble growth. The results indicate that oxygen breathing at 25 kPa promotes air bubble growth in adipose tissue regardless of the tissue nitrogen pressure Udgivelsesdato: 2008/11......At altitude, bubbles are known to form and grow in blood and tissues causing altitude decompression sickness. Previous reports indicate that treatment of decompression sickness by means of oxygen breathing at altitude may cause unwanted bubble growth. In this report we visually followed the in vivo.......7) after which they started shrinking or remained stable throughout the observation period. Bubble growth time was significantly longer during oxygen breathing compared with heliox breathing and preoxygenated animals. Significantly more bubbles disappeared in preoxygenated animals compared with oxygen...

  14. Brain Extraction and Fuzzy Tissue Segmentation in Cerebral 2D T1-Weigthed Magnetic Resonance Images

    Directory of Open Access Journals (Sweden)

    Bouchaib Cherradi

    2011-05-01

    Full Text Available In medical imaging, accurate segmentation of brain MR images is of interest for many brain manipulations. In this paper, we present a method for brain Extraction and tissues classification. An application of this method to the segmentation of simulated MRI cerebral images in three clusters will be made. The studied method is composed with different stages, first Brain Extraction from T1-weighted 2D MRI slices (TMBE is performed as pre-processing procedure, then Histogram based centroids initialization is done, and finally the fuzzy c-means clustering algorithm is applied on the results to segment the image in three clusters. The introduction of this pre-processing procedure has been made in the goal to have a targeted segmentation method. The convergence speed for tissues classification has been considerably improved by avoiding a random initialization of the cluster centres and reduction of the volume of data processing.

  15. Investigation on metal elements in the brain tissues from DNTC patients

    Energy Technology Data Exchange (ETDEWEB)

    Ide-Ektessabi, Ari E-mail: h51167@sakura.kudpc.kyoto-u.ac.jp; Kawakami, Takuo; Ishihara, Ryoko; Mizuno, Yutaka; Takeuchi, Tohru

    2004-07-01

    Trace metallic elements in human cells play important roles in various cell functions as metalloprotein, metalloenzyme or metallic ions. Diffuse neurofibrillary tangles with calcification (DNTC) is an atypical dementia and is characterized pathologically by diffuse neurofibrillary tangles without senile plaques. In this study, X-ray fluorescence (XRF) spectroscopy using synchrotron radiation (SR) was applied to determine the distribution and density of the ultra-trace elements in the brain tissues from DTNC patients. This method made it possible to determine trace metallic elements non-destructively. The trace metallic elements (such as Ca, Fe, Zn, and Pb) in the brain tissues were examined. Two-dimension imaging of the elements and relative quantification of the elements in the brains were performed. The lead concentrations were observed in the calcified blood vessel in the brains with DNTC.

  16. The NSW brain tissue resource centre: Banking for alcohol and major neuropsychiatric disorders research.

    Science.gov (United States)

    Sutherland, G T; Sheedy, D; Stevens, J; McCrossin, T; Smith, C C; van Roijen, M; Kril, J J

    2016-05-01

    The New South Wales Brain Tissue Resource Centre (NSWBTRC) at the University of Sydney (Australia) is an established human brain bank providing tissue to the neuroscience research community for investigations on alcohol-related brain damage and major psychiatric illnesses such as schizophrenia. The NSWBTRC relies on wide community engagement to encourage those with and without neuropsychiatric illness to consent to donation through its allied research programs. The subsequent provision of high-quality samples relies on standardized operational protocols, associated clinical data, quality control measures, integrated information systems, robust infrastructure, and governance. These processes are continually augmented to complement the changes in internal and external governance as well as the complexity and diversity of advanced investigation techniques. This report provides an overview of the dynamic process of brain banking and discusses the challenges of meeting the future needs of researchers, including synchronicity with other disease-focus collections.

  17. The NSW brain tissue resource centre: Banking for alcohol and major neuropsychiatric disorders research.

    Science.gov (United States)

    Sutherland, G T; Sheedy, D; Stevens, J; McCrossin, T; Smith, C C; van Roijen, M; Kril, J J

    2016-05-01

    The New South Wales Brain Tissue Resource Centre (NSWBTRC) at the University of Sydney (Australia) is an established human brain bank providing tissue to the neuroscience research community for investigations on alcohol-related brain damage and major psychiatric illnesses such as schizophrenia. The NSWBTRC relies on wide community engagement to encourage those with and without neuropsychiatric illness to consent to donation through its allied research programs. The subsequent provision of high-quality samples relies on standardized operational protocols, associated clinical data, quality control measures, integrated information systems, robust infrastructure, and governance. These processes are continually augmented to complement the changes in internal and external governance as well as the complexity and diversity of advanced investigation techniques. This report provides an overview of the dynamic process of brain banking and discusses the challenges of meeting the future needs of researchers, including synchronicity with other disease-focus collections. PMID:27139235

  18. Influence of oxygen tension on myocardial performance. Evaluation by tissue Doppler imaging

    Directory of Open Access Journals (Sweden)

    Poulsen Steen

    2004-11-01

    Full Text Available Abstract Background Low O2 tension dilates coronary arteries and high O2 tension is a coronary vasoconstrictor but reports on O2-dependent effects on ventricular performance diverge. Yet oxygen supplementation remains first line treatment in cardiovascular disease. We hypothesized that hypoxia improves and hyperoxia worsens myocardial performance. Methods Seven male volunteers (mean age 38 ± 3 years were examined with echocardiography at respiratory equilibrium during: 1 normoxia (≈21% O2, 79% N2, 2 while inhaling a hypoxic gas mixture (≈11% O2, 89% N2, and 3 while inhaling 100% O2. Tissue Doppler recordings were acquired in the apical 4-chamber, 2-chamber, and long-axis views. Strain rate and tissue tracking displacement analyses were carried out in each segment of the 16-segment left ventricular model and in the basal, middle and apical portions of the right ventricle. Results Heart rate increased with hypoxia (68 ± 4 bpm at normoxia vs. 79 ± 5 bpm, P Conclusion Hypoxia improves and hyperoxia worsens systolic myocardial performance in healthy male volunteers. Tissue Doppler measures of diastolic function are unaffected by hypoxia/hyperoxia which support that the changes in myocardial performance are secondary to changes in vascular tone. It remains to be settled whether oxygen therapy to patients with heart disease is a consistent rational treatment.

  19. Features of microelement maintenance in rat's brain tissues at experimental hypoxia of different degree.

    Directory of Open Access Journals (Sweden)

    Tarasova I.V.

    2011-01-01

    Full Text Available Features of microelement maintenance (iron, zinc, copper, manganese, and cobalt, conditionally toxic chrome and toxic lead were studied in newborn rat's brain tissues at experimental hypoxia of different degree. Tissues of newborn rat’s brain are characterized by high level of saturation and considerable dynamism of microelement maintenance. Till the end of the first week of life, the maintenance of these microelements decreases in 1,5 – 10 times. The level of the toxic lead decreases more than in 2,5 times. The hypoxia of easy degree of newborn rats invokes reduction cobalt level 3 times, iron level 2 times, manganese – on 27,65 %, chrome – on 25,84%, zinc – on 16,43%. It means that considerable deficiency and disbalance of microelement maintenance rat's brain tissues. The heavy degree of hypoxia is characterized by further increase of deficiency and disbalance of microelements.

  20. Distribution of lead in the brain tissues from DNTC patients using synchrotron radiation microbeams

    Energy Technology Data Exchange (ETDEWEB)

    Ide-Ektessabi, Ari [International Innovation Center, Kyoto University, Kyoto (Japan); Ota, Yukihide [Department of Precision Engineering, Kyoto University, Yoshida Honnmachi, Sakyo-ku, Kyoto (Japan)]. E-mail: h51167@sakura.kudpc.kyoto-u.ac.jp; Ishihara, Ryoko [Department of Psychiatry, Nagoya University, Graduate School of Medicine, Nagoya (Japan); Mizuno, Yutaka [Obu Dementia Care Research and Training Center, Obu (Japan); Takeuchi, Tohru [Department of Psychiatry, Nagoya University, Graduate School of Medicine, Nagoya (Japan)

    2005-12-15

    Diffuse neurofibrillary tangles with calcification (DNTC) is a form of dementia with certain characteristics. Its pathology is characterized by cerebrum atrophy, calcification on globus pallidus and dentate nucleus and diffuse neurofibrillary tangles without senile plaques. In the present study brain tissues were prepared from patients with patients DNTC, calcified and non-calcified Alzheimer's disease (AD) patients. The brain tissues were examined non-destructively by X-ray fluorescence (XRF) spectroscopy using synchrotron radiation (SR) microbeams for trace metallic elements Ca, Fe, Cu, Zn and Pb. The XRF analysis showed that there were Pb concentrations in the calcified areas in the brain tissues with both DNTC and AD but there was none in those with non-calcified AD.

  1. Effect of pineapple peel extract on total phospholipids and lipid peroxidation in brain tissues of rats

    Institute of Scientific and Technical Information of China (English)

    Erukainure OL; Ajiboye JA; Adejobi RO; Okafor OY; Kosoko SB; Owolabi FO

    2011-01-01

    Objective:To investigate the ability of the methanolic extract of pineapple peel to attenuate alcohol-induced changes in total phospholipids and lipid peroxidation in brain tissues. Methods:Oxidative stress was induced by oral administration of ethanol (20%w/v) at a dosage of 5 mL/kg bw in rats. After 28 days of treatment, the rats were fasted overnight and sacrificed by cervical dislocation. Brain tissues were assayed for total phospholipid (TP) content and malondialdehyde (MDA). Results:Administration of alcohol significantly caused a reduction in TP content. Treatment with pineapple peel extract significantly increased the TP content. Significant high levels of MDA was observed in alcohol-fed rats, treatment with pineapple peel extract significantly reduced the MDA levels. Conclusions:Results obtained from this study indicates that pineapple peel extract protects against alcohol-induced changes in total phospholipids and lipid peroxidation in brain tissues.

  2. Segmenting Brain Tissues from Chinese Visible Human Dataset by Deep-Learned Features with Stacked Autoencoder

    OpenAIRE

    Guangjun Zhao; Xuchu Wang; Yanmin Niu; Liwen Tan; Shao-Xiang Zhang

    2016-01-01

    Cryosection brain images in Chinese Visible Human (CVH) dataset contain rich anatomical structure information of tissues because of its high resolution (e.g., 0.167 mm per pixel). Fast and accurate segmentation of these images into white matter, gray matter, and cerebrospinal fluid plays a critical role in analyzing and measuring the anatomical structures of human brain. However, most existing automated segmentation methods are designed for computed tomography or magnetic resonance imaging da...

  3. Challenges in understanding the impact of blood pressure management on cerebral oxygenation in the preterm brain

    Directory of Open Access Journals (Sweden)

    Aminath eAzhan

    2012-12-01

    Full Text Available Systemic hypotension in preterm infants has been related to increased mortality, cerebrovascular lesions and neurodevelopmental morbidity. Treatment of hypotension with inotropic medications aims at preservation of end organ perfusion and oxygen delivery, especially the brain. The common inotropic medications in preterm infants include dopamine, dobutamine, adrenalin, with adjunctive use of corticosteroids in cases of refractory hypotension. Whether maintenance of mean arterial blood pressure (MAP by use of inotropic medication is neuroprotective or not remains unclear. This review explores the different inotropic agents and their effects on perfusion and oxygenation in the preterm brain, in clinical studies as well as in animal models. Dopamine and adrenalin, because of their -adrenergic vasoconstrictor actions, have raised concerns of reduction in cerebral blood flow (CBF. Several studies in hypotensive preterm infants have shown that dopamine elevates CBF together with increased MAP, in keeping with limited cerebro-autoregulation. Adrenaline is also effective in raising cerebral perfusion together with MAP in preterm infants. Experimental studies in immature animals show no cerebro-vasoconstrictive effects of dopamine or adrenaline, but demonstrate the consistent findings of increased cerebral perfusion and oxygenation with the use of dopamine, dobutamine and adrenaline, alongside with raised MAP. Both clinical and animal studies report the transitory effects of adrenaline in increasing plasma lactate, and blood glucose, which might render its use as a 2nd line therapy. To investigate the cerebral effects of inotropic agents in long-term outcome in hypotensive preterm infants, carefully designed prospective research possibly including preterm infants with permissive hypotension is required. Preterm animal models would be useful in investigating the relationship between the physiological effects of inotropes and histopathology outcomes in

  4. Three-dimensional structure of brain tissue at submicrometer resolution

    International Nuclear Information System (INIS)

    Biological objects are composed of submicrometer structures such as cells and organelles that are essential for their functions. Here, we report on three-dimensional X-ray visualization of cells and organelles at resolutions up to 100 nm by imaging microtomography (micro-CT) equipped with Fresnel zone plate optics. Human cerebral tissue, fruit fly cephalic ganglia, and Escherichia coli bacteria labeled with high atomic-number elements were embedded in epoxy resin and subjected to X-ray microtomography at the BL37XU and BL47XU beamlines of the SPring-8 synchrotron radiation facility. The obtained results indicated that soft tissue structures can be visualized with the imaging microtomography

  5. Three-dimensional structure of brain tissue at submicrometer resolution

    Energy Technology Data Exchange (ETDEWEB)

    Saiga, Rino; Mizutani, Ryuta, E-mail: ryuta@tokai-u.jp [Department of Applied Biochemistry, Tokai University, Hiratsuka, Kanagawa 259-1292 (Japan); Inomoto, Chie; Takekoshi, Susumu; Nakamura, Naoya; Tsuboi, Akio; Osawa, Motoki [Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Arai, Makoto; Oshima, Kenichi; Itokawa, Masanari [Tokyo Metropolitan Institute of Medical Science, Setagaya, Tokyo 156-8506 (Japan); Uesugi, Kentaro; Takeuchi, Akihisa; Terada, Yasuko; Suzuki, Yoshio [Japan Synchrotron Radiation Research Institute (JASRI/SPring-8), Sayo, Hyogo 679-5198 (Japan)

    2016-01-28

    Biological objects are composed of submicrometer structures such as cells and organelles that are essential for their functions. Here, we report on three-dimensional X-ray visualization of cells and organelles at resolutions up to 100 nm by imaging microtomography (micro-CT) equipped with Fresnel zone plate optics. Human cerebral tissue, fruit fly cephalic ganglia, and Escherichia coli bacteria labeled with high atomic-number elements were embedded in epoxy resin and subjected to X-ray microtomography at the BL37XU and BL47XU beamlines of the SPring-8 synchrotron radiation facility. The obtained results indicated that soft tissue structures can be visualized with the imaging microtomography.

  6. Neuronal inhibition and excitation, and the dichotomic control of brain hemodynamic and oxygen responses

    DEFF Research Database (Denmark)

    Lauritzen, Martin; Mathiesen, Claus; Schaefer, Katharina;

    2012-01-01

    Brain's electrical activity correlates strongly to changes in cerebral blood flow (CBF) and the cerebral metabolic rate of oxygen (CMRO(2)). Subthreshold synaptic processes correlate better than the spike rates of principal neurons to CBF, CMRO(2) and positive BOLD signals. Stimulation...... metabolic and vascular control explains the gap between the stimulation-induced rises in CMRO(2) and CBF, and in turn the BOLD signal. Activity-dependent rises in CBF and CMRO(2) vary within and between brain regions due to differences in ATP turnover and Ca(2+)-dependent mechanisms. Nerve cells produce and...... release vasodilators that evoke positive BOLD signals, while the mechanisms that control negative BOLD signals by activity-dependent vasoconstriction are less well understood. Activation of both excitatory and inhibitory neurons produces rises in CBF and positive BOLD signals, while negative BOLD signals...

  7. Protective effects of acupuncture on brain tissue following ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Mingshan Wang; Fuguo Ma; Huailong Chen

    2008-01-01

    BACKGROUND: In patients with cerebrovascular disease, by means of the neuroendocrine system, acupuncture supports the transformation of a local pathological status into a physiological status. Recently, great progress has been made in studying the protective effects of acupuncture on brain ischemia/reperfusion injury. OBJECTIVE: To summarize research advances in the protective effects of acupuncture on brain ischemia/reperfusion injury. RETRIEVAL STRATEGY: Using the terms "acupuncture, transcutaneous electrical acupoint stimulation, cerebral ischemia/reperfusion injury, and cerebral protection", we retrieved articles from the PubMed database published between January 1991 and June 1994. Meanwhile, we searched the China National Knowledge Infrastructure with the same terms. Altogether, 114 articles and their results were analyzed. Inclusive criteria: studies that were closely related to the protective effects of acupuncture on brain ischemia/reperfusion injury, or studies, whose contents were in the same study field and were published recently, or in the authorized journals. Exclusive criteria: repetitive studies. LITERATURE EVALUATION: Thirty articles that related to the protective effects of acupuncture on brain ischemia/reperfusion injury were included. Among them, 7 were clinical studies, and the remaining 23 articles were animal experimental studies. DATA SYNTHESIS: ① Animal experimental studies have demonstrated that acupuncture improves brain blood perfusion and brain electrical activity, influences pathomorphological and ultramicrostructural changes in ischemic brain tissue, is beneficial in maintaining the stability of intracellular and extracellular ions, resists free radical injury and lipid peroxidation, and influences cytokine, neurotransmitter, brain cell signal transduction, and apoptosis-regulating genes. ② Clinical studies have demonstrated that acupuncture not only promotes nutritional supply to local brain tissue in patients with cerebral

  8. Determinants of renal tissue oxygenation as measured with BOLD-MRI in chronic kidney disease and hypertension in humans.

    OpenAIRE

    Pruijm, Menno; Hofmann, Lucie; Piskunowicz, Maciej; Muller, Marie-Eve; Zweiacker, Carole; Bassi, Isabelle; Vogt, Bruno; Stuber, Matthias; Burnier, Michel

    2014-01-01

    Experimentally renal tissue hypoxia appears to play an important role in the pathogenesis of chronic kidney disease (CKD) and arterial hypertension (AHT). In this study we measured renal tissue oxygenation and its determinants in humans using blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI) under standardized hydration conditions. Four coronal slices were selected, and a multi gradient echo sequence was used to acquire T2* weighted images. The mean cortical and medullar...

  9. Determinants of Renal Tissue Oxygenation as Measured with BOLD-MRI in Chronic Kidney Disease and Hypertension in Humans

    OpenAIRE

    Menno Pruijm; Lucie Hofmann; Maciej Piskunowicz; Marie-Eve Muller; Carole Zweiacker; Isabelle Bassi; Bruno Vogt; Matthias Stuber; Michel Burnier

    2014-01-01

    Experimentally renal tissue hypoxia appears to play an important role in the pathogenesis of chronic kidney disease (CKD) and arterial hypertension (AHT). In this study we measured renal tissue oxygenation and its determinants in humans using blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI) under standardized hydration conditions. Four coronal slices were selected, and a multi gradient echo sequence was used to acquire T2* weighted images. The mean cortical and medullar...

  10. High-resolution x-ray absorption spectroscopy studies of metal compounds in neurodegenerative brain tissue

    Energy Technology Data Exchange (ETDEWEB)

    Collingwood, J.F.; Mikhaylova, A.; Davidson, M.R.; Batich, C.; Streit, W.J.; Eskin, T.; Terry, J.; Barrea, R.; Underhill, R.S.; Dobson, J. (IIT); (Keele); (Florida); (DRDC)

    2008-06-16

    Fluorescence mapping and microfocus X-ray absorption spectroscopy are used to detect, locate and identify iron biominerals and other inorganic metal accumulations in neurodegenerative brain tissue at sub-cellular resolution (< 5 microns). Recent progress in developing the technique is reviewed. Synchrotron X-rays are used to map tissue sections for metals of interest, and XANES and XAFS are used to characterize anomalous concentrations of the metals in-situ so that they can be correlated with tissue structures and disease pathology. Iron anomalies associated with biogenic magnetite, ferritin and haemoglobin are located and identified in an avian tissue model with a pixel resolution {approx} 5 microns. Subsequent studies include brain tissue sections from transgenic Huntington's mice, and the first high-resolution mapping and identification of iron biominerals in human Alzheimer's and control autopsy brain tissue. Technical developments include use of microfocus diffraction to obtain structural information about biominerals in-situ, and depositing sample location grids by lithography for the location of anomalies by conventional microscopy. The combined techniques provide a breakthrough in the study of both intra- and extra-cellular iron compounds and related metals in tissue. The information to be gained from this approach has implications for future diagnosis and treatment of neurodegeneration, and for our understanding of the mechanisms involved.

  11. Hyperbaric oxygen therapy for traumatic brain injury: bench-to-bedside

    Directory of Open Access Journals (Sweden)

    Qin Hu

    2016-01-01

    Full Text Available Traumatic brain injury (TBI is a serious public health problem in the United States. Survivors of TBI are often left with significant cognitive, behavioral, and communicative disabilities. So far there is no effective treatment/intervention in the daily clinical practice for TBI patients. The protective effects of hyperbaric oxygen therapy (HBOT have been proved in stroke; however, its efficiency in TBI remains controversial. In this review, we will summarize the results of HBOT in experimental and clinical TBI, elaborate the mechanisms, and bring out our current understanding and opinions for future studies.

  12. Segmenting Brain Tissues from Chinese Visible Human Dataset by Deep-Learned Features with Stacked Autoencoder

    Directory of Open Access Journals (Sweden)

    Guangjun Zhao

    2016-01-01

    Full Text Available Cryosection brain images in Chinese Visible Human (CVH dataset contain rich anatomical structure information of tissues because of its high resolution (e.g., 0.167 mm per pixel. Fast and accurate segmentation of these images into white matter, gray matter, and cerebrospinal fluid plays a critical role in analyzing and measuring the anatomical structures of human brain. However, most existing automated segmentation methods are designed for computed tomography or magnetic resonance imaging data, and they may not be applicable for cryosection images due to the imaging difference. In this paper, we propose a supervised learning-based CVH brain tissues segmentation method that uses stacked autoencoder (SAE to automatically learn the deep feature representations. Specifically, our model includes two successive parts where two three-layer SAEs take image patches as input to learn the complex anatomical feature representation, and then these features are sent to Softmax classifier for inferring the labels. Experimental results validated the effectiveness of our method and showed that it outperformed four other classical brain tissue detection strategies. Furthermore, we reconstructed three-dimensional surfaces of these tissues, which show their potential in exploring the high-resolution anatomical structures of human brain.

  13. Segmenting Brain Tissues from Chinese Visible Human Dataset by Deep-Learned Features with Stacked Autoencoder.

    Science.gov (United States)

    Zhao, Guangjun; Wang, Xuchu; Niu, Yanmin; Tan, Liwen; Zhang, Shao-Xiang

    2016-01-01

    Cryosection brain images in Chinese Visible Human (CVH) dataset contain rich anatomical structure information of tissues because of its high resolution (e.g., 0.167 mm per pixel). Fast and accurate segmentation of these images into white matter, gray matter, and cerebrospinal fluid plays a critical role in analyzing and measuring the anatomical structures of human brain. However, most existing automated segmentation methods are designed for computed tomography or magnetic resonance imaging data, and they may not be applicable for cryosection images due to the imaging difference. In this paper, we propose a supervised learning-based CVH brain tissues segmentation method that uses stacked autoencoder (SAE) to automatically learn the deep feature representations. Specifically, our model includes two successive parts where two three-layer SAEs take image patches as input to learn the complex anatomical feature representation, and then these features are sent to Softmax classifier for inferring the labels. Experimental results validated the effectiveness of our method and showed that it outperformed four other classical brain tissue detection strategies. Furthermore, we reconstructed three-dimensional surfaces of these tissues, which show their potential in exploring the high-resolution anatomical structures of human brain. PMID:27057543

  14. Brain tissue segmentation in 4D CT using voxel classification

    Science.gov (United States)

    van den Boom, R.; Oei, M. T. H.; Lafebre, S.; Oostveen, L. J.; Meijer, F. J. A.; Steens, S. C. A.; Prokop, M.; van Ginneken, B.; Manniesing, R.

    2012-02-01

    A method is proposed to segment anatomical regions of the brain from 4D computer tomography (CT) patient data. The method consists of a three step voxel classification scheme, each step focusing on structures that are increasingly difficult to segment. The first step classifies air and bone, the second step classifies vessels and the third step classifies white matter, gray matter and cerebrospinal fluid. As features the time averaged intensity value and the temporal intensity change value were used. In each step, a k-Nearest-Neighbor classifier was used to classify the voxels. Training data was obtained by placing regions of interest in reconstructed 3D image data. The method has been applied to ten 4D CT cerebral patient data. A leave-one-out experiment showed consistent and accurate segmentation results.

  15. The Neuroprotective Effect of Cornus mas on Brain Tissue of Wistar Rats

    Directory of Open Access Journals (Sweden)

    Renata Francik

    2014-01-01

    Full Text Available Cornelian cherry (Cornus mas is a valuable source of phenolic antioxidants. Flavonoid derivatives as nonenzymatic antioxidants are important in the pathophysiology of many diseases including neurological disorders (e.g., Alzheimer’s disease or heart disease. In this study, we examined the effect of an addition of freeze-dried fruit of cornelian cherry on three types of diets: control diet, fructose diet, and diet enriched in fats (high-fat diet. This effect was studied by determining the following antioxidant parameters in both brain tissue and plasma in rats: catalase, ferric reducing ability of plasma, paraoxonase, protein carbonyl groups, and free thiol groups. Results indicate that both fructose diet and high-fat diet affect the antioxidant capacity of the organism. Furthermore, an addition of cornelian cherry resulted in increased activity of catalase in brain tissue, while in plasma it caused the opposite effect. In turn, with regard to paraoxonase activity in both brain tissue and plasma, it had a stimulating effect. Adding cornelian cherry to the tested diets increased the activity of PON in both tested tissues. Moreover, protective effect of fruits of this plant was observed in the process of oxidation of proteins by decreasing levels of protein carbonyl groups and thiol groups in brain tissue as well as in plasma.

  16. Cyclosporine treatment reduces oxygen free radical generation and oxidative stress in the brain of hypoxia-reoxygenated newborn piglets.

    Directory of Open Access Journals (Sweden)

    Richdeep S Gill

    Full Text Available Oxygen free radicals have been implicated in the pathogenesis of hypoxic-ischemic encephalopathy. It has previously been shown in traumatic brain injury animal models that treatment with cyclosporine reduces brain injury. However, the potential neuroprotective effect of cyclosporine in asphyxiated neonates has yet to be fully studied. Using an acute newborn swine model of hypoxia-reoxygenation, we evaluated the effects of cyclosporine on the brain, focusing on hydrogen peroxide (H(2O(2 production and markers of oxidative stress. Piglets (1-4 d, 1.4-2.5 kg were block-randomized into three hypoxia-reoxygenation experimental groups (2 h hypoxia followed by 4 h reoxygenation (n = 8/group. At 5 min after reoxygenation, piglets were given either i.v. saline (placebo, controls or cyclosporine (2.5 or 10 mg/kg i.v. bolus in a blinded-randomized fashion. An additional sham-operated group (n = 4 underwent no hypoxia-reoxygenation. Systemic hemodynamics, carotid arterial blood flow (transit-time ultrasonic probe, cerebral cortical H(2O(2 production (electrochemical sensor, cerebral tissue glutathione (ELISA and cytosolic cytochrome-c (western blot levels were examined. Hypoxic piglets had cardiogenic shock (cardiac output 40-48% of baseline, hypotension (mean arterial pressure 27-31 mmHg and acidosis (pH 7.04 at the end of 2 h of hypoxia. Post-resuscitation cyclosporine treatment, particularly the higher dose (10 mg/kg, significantly attenuated the increase in cortical H(2O(2 concentration during reoxygenation, and was associated with lower cerebral oxidized glutathione levels. Furthermore, cyclosporine treatment significantly attenuated the increase in cortical cytochrome-c and lactate levels. Carotid blood arterial flow was similar among groups during reoxygenation. Conclusively, post-resuscitation administration of cyclosporine significantly attenuates H(2O(2 production and minimizes oxidative stress in newborn piglets following hypoxia-reoxygenation.

  17. Cyclosporine Treatment Reduces Oxygen Free Radical Generation and Oxidative Stress in the Brain of Hypoxia-Reoxygenated Newborn Piglets

    Science.gov (United States)

    Liu, Jiang-Qin; Chaudhary, Hetal; Brocks, Dion R.; Bigam, David L.; Cheung, Po-Yin

    2012-01-01

    Oxygen free radicals have been implicated in the pathogenesis of hypoxic-ischemic encephalopathy. It has previously been shown in traumatic brain injury animal models that treatment with cyclosporine reduces brain injury. However, the potential neuroprotective effect of cyclosporine in asphyxiated neonates has yet to be fully studied. Using an acute newborn swine model of hypoxia-reoxygenation, we evaluated the effects of cyclosporine on the brain, focusing on hydrogen peroxide (H2O2) production and markers of oxidative stress. Piglets (1–4 d, 1.4–2.5 kg) were block-randomized into three hypoxia-reoxygenation experimental groups (2 h hypoxia followed by 4 h reoxygenation)(n = 8/group). At 5 min after reoxygenation, piglets were given either i.v. saline (placebo, controls) or cyclosporine (2.5 or 10 mg/kg i.v. bolus) in a blinded-randomized fashion. An additional sham-operated group (n = 4) underwent no hypoxia-reoxygenation. Systemic hemodynamics, carotid arterial blood flow (transit-time ultrasonic probe), cerebral cortical H2O2 production (electrochemical sensor), cerebral tissue glutathione (ELISA) and cytosolic cytochrome-c (western blot) levels were examined. Hypoxic piglets had cardiogenic shock (cardiac output 40–48% of baseline), hypotension (mean arterial pressure 27–31 mmHg) and acidosis (pH 7.04) at the end of 2 h of hypoxia. Post-resuscitation cyclosporine treatment, particularly the higher dose (10 mg/kg), significantly attenuated the increase in cortical H2O2 concentration during reoxygenation, and was associated with lower cerebral oxidized glutathione levels. Furthermore, cyclosporine treatment significantly attenuated the increase in cortical cytochrome-c and lactate levels. Carotid blood arterial flow was similar among groups during reoxygenation. Conclusively, post-resuscitation administration of cyclosporine significantly attenuates H2O2 production and minimizes oxidative stress in newborn piglets following hypoxia

  18. 65zinc uptake from blood into brain and other tissues in the rat

    International Nuclear Information System (INIS)

    Zinc is essential for normal growth, development and brain function although little is known about brain zinc homeostasis. Therefore, in this investigation we have studied 65Zn uptake from blood into brain and other tissues and have measured the blood-brain barrier permeability to 65Zn in the anaesthetized rat in vivo. Adult male Wistar rats within the weight range 500-600 g were used. 65ZnCl2 and [125I]albumin, the latter serving as a vascular marker, were injected in a bolus of normal saline I.V. Sequential arterial blood samples were taken during experiments that lasted between 5 min and 5 hr. At termination, samples from the liver, spleen, pancreas, lung, heart, muscle, kidney, bone, testis, ileum, blood cells, csf, and whole brain were taken and analysed for radio-isotope activity. Data have been analysed by Graphical Analysis which suggests 65Zn uptake from blood by all tissues sampled was unidirectional during this experimental period except brain, where at circulation times less than 30 min, 65Zn fluxes were bidirectional. In addition to the blood space, the brain appears to contain a rapidly exchanging compartment(s) for 65Zn of about 4 ml/100g which is not csf

  19. 小鼠短跑缺氧状态下脑部含氧量下降趋势分析%Analysis of Mice Brain Oxygen Levels Decline Under a Lack of Oxygen Condition

    Institute of Scientific and Technical Information of China (English)

    袁本坛

    2014-01-01

    Objective:To analyse tate of brain oxygen levels decline under mice sprint training. Methods:Choose healthy kunming mice, divided into 1 hou ,2 hours, 3 hours sprint training group (18), each group included in the control group, a lack of oxygen and oxygen to four group three groups, each group 6 mice, male and female half, each big groups of mice, the Griess method detection means, in different sprint training group mice, in hypoxia state changes of the cerebral oxygen, are analyzed in the experiment. Results:With the increase of physical activity in mice, the mice body weight, decrease of 3 hours training group mice body weight was significantly less than 1 hour training, 1 hour, 2 hours and 3 hours of sprint training small white mouse tissue oxygenation of the midbrain as sprint motion of oxygen level enhancement, and the average and 3 hours for sprint training group mice brain oxygen levels below the average of 2 hours training mice brain oxygen, far below the average of 1 hour training mice brain oxygen. Conclusion:In this paper, the experiment result shows that the brain oxygen levels in the process of sprint movement in mice with the degree of movement of oxygen, increase the number of times is reduced, and the sprint exercise intensity, the greater the little mouse higher oxygen levels decline.%目的:分析短跑缺氧状态下脑部含氧量下降趋势。方法:选用健康昆明小鼠,分为1h、2h、3h短跑训练组(各18只),每组包括对照组、1次缺氧组和4次缺氧组3小组,每小组6只小鼠,雌雄各半,每大组18只小鼠,采用Griess法检测手段,对不同短跑训练组小鼠,在缺氧状态脑含氧量的变化情况,进行了实验分析。结果:随着小鼠运动量的增加,小鼠体重不断降低,3h训练组小鼠体重显著低于1h训练组,1h、2h以及3h短跑训练组小白鼠脑组织中脑含氧量随着短跑运动缺氧程度的增强而降低,并且3h短跑训练组

  20. Blood flow and oxygenation in peritendinous tissue and calf muscle during dynamic exercise in humans

    DEFF Research Database (Denmark)

    Boushel, R; Langberg, Henning; Green, Stefan Mathias;

    2000-01-01

    1. Circulation around tendons may act as a shunt for muscle during exercise. The perfusion and oxygenation of Achilles' peritendinous tissue was measured in parallel with that of calf muscle during exercise to determine (1) whether blood flow is restricted in peritendinous tissue during exercise......, and (2) whether blood flow is coupled to oxidative metabolism. 2. Seven individuals performed dynamic plantar flexion from 1 to 9 W. Radial artery and popliteal venous blood were sampled for O2, peritendinous blood flow was determined by 133Xe-washout, calf blood flow by plethysmography, cardiac output...... by dye dilution, arterial pressure by an arterial catheter-transducer, and muscle and peritendinous O2 saturation by spatially resolved spectroscopy (SRS). 3. Calf blood flow rose 20-fold with exercise, reaching 44 +/- 7 ml (100 g)-1 min-1 (mean +/- s.e.m. ) at 9 W, while Achilles' peritendinous flow...

  1. Evaluation of tissue oxygen measurements for flap monitoring in an animal model

    DEFF Research Database (Denmark)

    Bonde, Christian; Elberg, Jens; Holstein-Rathlou, N.-H.

    2008-01-01

    Tissue oxygen tension (p(ti)O(2)) measurements are common in neurosurgery but uncommon in plastic surgery. We examined this technique as a monitoring method with probe placement in the subcutaneous tissue and addressed the importance of probe placement. Myocutaneous flaps were raised in an animal......) was 18 minutes. We found no significant relation between initial levels of p(ti)O(2) and T(1/2). Location of the probe and absolute p(ti)O(2) value is of little relevance for flap monitoring. It is the relative change in p(ti)O(2) that is important. The p(ti)O(2) technique is well suited for monitoring...

  2. Changes in brain tissue and behavior patterns induced by single short-term fasting in mice.

    Directory of Open Access Journals (Sweden)

    Yuko Hisatomi

    Full Text Available In humans, emaciation from long-term dietary deficiencies, such as anorexia, reportedly increases physical activity and brain atrophy. However, the effects of single short-term fasting on brain tissue or behavioral activity patterns remain unclear. To clarify the impact of malnutrition on brain function, we conducted a single short-term fasting study as an anorexia model using male adult mice and determined if changes occurred in migratory behavior as an expression of brain function and in brain tissue structure. Sixteen-week-old C57BL/6J male mice were divided into either the fasted group or the control group. Experiments were conducted in a fixed indoor environment. We examined the effects of fasting on the number of nerve cells, structural changes in the myelin and axon density, and brain atrophy. For behavior observation, the amount of food and water consumed, ingestion time, and the pattern of movement were measured using a time-recording system. The fasted mice showed a significant increase in physical activity and their rhythm of movement was disturbed. Since the brain was in an abnormal state after fasting, mice that were normally active during the night became active regardless of day or night and performed strenuous exercise at a high frequency. The brain weight did not change by a fast, and brain atrophy was not observed. Although no textural change was apparent by fasting, the neuronal neogenesis in the subventricular zone and hippocampus was inhibited, causing disorder of the brain function. A clear association between the suppression of encephalic neuropoiesis and overactivity was not established. However, it is interesting that the results of this study suggest that single short-term fasting has an effect on encephalic neuropoiesis.

  3. Changes in Brain Tissue and Behavior Patterns Induced by Single Short-Term Fasting in Mice

    Science.gov (United States)

    Hisatomi, Yuko; Asakura, Kyo; Kugino, Kenji; Kurokawa, Mamoru; Asakura, Tomiko; Nakata, Keiko

    2013-01-01

    In humans, emaciation from long-term dietary deficiencies, such as anorexia, reportedly increases physical activity and brain atrophy. However, the effects of single short-term fasting on brain tissue or behavioral activity patterns remain unclear. To clarify the impact of malnutrition on brain function, we conducted a single short-term fasting study as an anorexia model using male adult mice and determined if changes occurred in migratory behavior as an expression of brain function and in brain tissue structure. Sixteen-week-old C57BL/6J male mice were divided into either the fasted group or the control group. Experiments were conducted in a fixed indoor environment. We examined the effects of fasting on the number of nerve cells, structural changes in the myelin and axon density, and brain atrophy. For behavior observation, the amount of food and water consumed, ingestion time, and the pattern of movement were measured using a time-recording system. The fasted mice showed a significant increase in physical activity and their rhythm of movement was disturbed. Since the brain was in an abnormal state after fasting, mice that were normally active during the night became active regardless of day or night and performed strenuous exercise at a high frequency. The brain weight did not change by a fast, and brain atrophy was not observed. Although no textural change was apparent by fasting, the neuronal neogenesis in the subventricular zone and hippocampus was inhibited, causing disorder of the brain function. A clear association between the suppression of encephalic neuropoiesis and overactivity was not established. However, it is interesting that the results of this study suggest that single short-term fasting has an effect on encephalic neuropoiesis. PMID:24224039

  4. Exercise induces autophagy in peripheral tissues and in the brain

    OpenAIRE

    He, Congcong; Sumpter, Jr., Rhea; Levine, Beth

    2012-01-01

    We recently identified physical exercise as a newly defined inducer of autophagy in vivo. Exercise induced autophagy in multiple organs involved in metabolic regulation, such as muscle, liver, pancreas and adipose tissue. To study the physiological role of exercise-induced autophagy, we generated mice with a knock-in nonphosphorylatable mutation in BCL2 (Thr69Ala, Ser70Ala and Ser84Ala) (BCL2 AAA) that are defective in exercise- and starvation-induced autophagy but not in basal autophagy. We ...

  5. Hyperbaric oxygen therapy or hydroxycobalamin attenuates surges in brain interstitial lactate and glucose; and hyperbaric oxygen improves respiratory status in cyanide-intoxicated rats

    DEFF Research Database (Denmark)

    Lawson-Smith, P; Olsen, Niels Vidiendal; Hyldegaard, Ole

    2011-01-01

    Cyanide (CN) intoxication inhibits cellular oxidative metabolism and may result in brain damage. Hydroxycobalamin (OHCob) is one among other antidotes that may be used following intoxication with CN. Hyperbaric oxygen (HBO2) is recommended when supportive measures or antidotes fail. However...

  6. Inhibition of HIF prolyl-4-hydroxylases by FG-4497 reduces brain tissue injury and edema formation during ischemic stroke.

    Science.gov (United States)

    Reischl, Stefan; Li, Lexiao; Walkinshaw, Gail; Flippin, Lee A; Marti, Hugo H; Kunze, Reiner

    2014-01-01

    Ischemic stroke results in disruption of the blood-brain barrier (BBB), edema formation and neuronal cell loss. Some neuroprotective factors such as vascular endothelial growth factor (VEGF) favor edema formation, while others such as erythropoietin (Epo) can mitigate it. Both factors are controlled by hypoxia inducible transcription factors (HIF) and the activity of prolyl hydroxylase domain proteins (PHD). We hypothesize that activation of the adaptive hypoxic response by inhibition of PHD results in neuroprotection and prevention of vascular leakage. Mice, subjected to cerebral ischemia, were pre- or post-treated with the novel PHD inhibitor FG-4497. Inhibition of PHD activity resulted in HIF-1α stabilization, increased expression of VEGF and Epo, improved outcome from ischemic stroke and reduced edema formation by maintaining BBB integrity. Additional in vitro studies using brain endothelial cells and primary astrocytes confirmed that FG-4497 induces the HIF signaling pathway, leading to increased VEGF and Epo expression. In an in vitro ischemia model, using combined oxygen and glucose deprivation, FG-4497 promoted the survival of neurons. Furthermore, FG-4497 prevented the ischemia-induced rearrangement and gap formation of the tight junction proteins zonula occludens 1 and occludin, both in cultured endothelial cells and in infarcted brain tissue in vivo. These results indicate that FG-4497 has the potential to prevent cerebral ischemic damage by neuroprotection and prevention of vascular leakage. PMID:24409307

  7. Inhibition of HIF prolyl-4-hydroxylases by FG-4497 reduces brain tissue injury and edema formation during ischemic stroke.

    Directory of Open Access Journals (Sweden)

    Stefan Reischl

    Full Text Available Ischemic stroke results in disruption of the blood-brain barrier (BBB, edema formation and neuronal cell loss. Some neuroprotective factors such as vascular endothelial growth factor (VEGF favor edema formation, while others such as erythropoietin (Epo can mitigate it. Both factors are controlled by hypoxia inducible transcription factors (HIF and the activity of prolyl hydroxylase domain proteins (PHD. We hypothesize that activation of the adaptive hypoxic response by inhibition of PHD results in neuroprotection and prevention of vascular leakage. Mice, subjected to cerebral ischemia, were pre- or post-treated with the novel PHD inhibitor FG-4497. Inhibition of PHD activity resulted in HIF-1α stabilization, increased expression of VEGF and Epo, improved outcome from ischemic stroke and reduced edema formation by maintaining BBB integrity. Additional in vitro studies using brain endothelial cells and primary astrocytes confirmed that FG-4497 induces the HIF signaling pathway, leading to increased VEGF and Epo expression. In an in vitro ischemia model, using combined oxygen and glucose deprivation, FG-4497 promoted the survival of neurons. Furthermore, FG-4497 prevented the ischemia-induced rearrangement and gap formation of the tight junction proteins zonula occludens 1 and occludin, both in cultured endothelial cells and in infarcted brain tissue in vivo. These results indicate that FG-4497 has the potential to prevent cerebral ischemic damage by neuroprotection and prevention of vascular leakage.

  8. Environmental changes in oxygen tension reveal ROS-dependent neurogenesis and regeneration in the adult newt brain.

    Science.gov (United States)

    Hameed, L Shahul; Berg, Daniel A; Belnoue, Laure; Jensen, Lasse D; Cao, Yihai; Simon, András

    2015-01-01

    Organisms need to adapt to the ecological constraints in their habitat. How specific processes reflect such adaptations are difficult to model experimentally. We tested whether environmental shifts in oxygen tension lead to events in the adult newt brain that share features with processes occurring during neuronal regeneration under normoxia. By experimental simulation of varying oxygen concentrations, we show that hypoxia followed by re-oxygenation lead to neuronal death and hallmarks of an injury response, including activation of neural stem cells ultimately leading to neurogenesis. Neural stem cells accumulate reactive oxygen species (ROS) during re-oxygenation and inhibition of ROS biosynthesis counteracts their proliferation as well as neurogenesis. Importantly, regeneration of dopamine neurons under normoxia also depends on ROS-production. These data demonstrate a role for ROS-production in neurogenesis in newts and suggest that this role may have been recruited to the capacity to replace lost neurons in the brain of an adult vertebrate. PMID:26485032

  9. Carcinoma cells misuse the host tissue damage response to invade the brain

    OpenAIRE

    Chuang, Han-Ning; van Rossum, Denise; Sieger, Dirk; Siam, Laila; Klemm, Florian; Bleckmann, Annalen; Bayerlová, Michaela; Farhat, Katja; Scheffel, Jörg; Schulz, Matthias; Dehghani, Faramarz; Stadelmann, Christine; Hanisch, Uwe-Karsten; Binder, Claudia; Pukrop, Tobias

    2013-01-01

    The metastatic colonization of the brain by carcinoma cells is still barely understood, in particular when considering interactions with the host tissue. The colonization comes with a substantial destruction of the surrounding host tissue. This leads to activation of damage responses by resident innate immune cells to protect, repair, and organize the wound healing, but may distract from tumoricidal actions. We recently demonstrated that microglia, innate immune cells of the CNS, assist carci...

  10. MALDI mass spectrometry based molecular phenotyping of CNS glial cells for prediction in mammalian brain tissue

    DEFF Research Database (Denmark)

    Hanrieder, Jørg; Wicher, Grzegorz; Bergquist, Jonas;

    2011-01-01

    The development of powerful analytical techniques for specific molecular characterization of neural cell types is of central relevance in neuroscience research for elucidating cellular functions in the central nervous system (CNS). This study examines the use of differential protein expression...... tracers for prediction of oligodendroglial and astroglial localization in brain tissue. The different cell type specific protein distributions in tissue were validated using immunohistochemistry. ICMS of intact neuroglia is a simple and straightforward approach for characterization and discrimination...

  11. Expression of Bcl-2 and NF-κB in brain tissue after acute renal ischemia-reperfusion in rats

    Institute of Scientific and Technical Information of China (English)

    Na Zhang; Gen-Yang Cheng; Xian-Zhi Liu; Feng-Jiang Zhang

    2014-01-01

    Objective:To investigate the effect of acute renal ischemia reperfusion on brain tissue. Methods:Fourty eight rats were randomly divided into four groups(n=12): sham operation group,30 min ischemia60 min reperfusion group,60 min ischemia60 min reperfusion group, and 120 min ischemia60 min reperfusion group.The brain tissues were taken after the experiment. TUNEL assay was used to detect the brain cell apoptosis, and western blot was used to detect the expression of apoptosis-related proteins and inflammatory factors.Results:Renal ischemia-reperfusion induced apoptosis of brain tissues, and the apoptosis increased with prolongation of ischemia time.The detection at the molecular level showed decreasedBcl-2 expression, increasedBax expression, upregulated expression ofNF-κB and its downstream factor COX-2/PGE2.Conclusions:Acute renal ischemia-reperfusion can cause brain tissue damage, manifested as induced brain tissues apoptosis and inflammation activation.

  12. Stable hydrogen, oxygen and sulfur isotopes composition in different tissues of cattle

    International Nuclear Information System (INIS)

    In order to research on stable hydrogen, oxygen, sulfur isotopes composition in different tissues of cattle, as well as the breed, δ 2H and δ 34S values of different defatted muscle, cattle tail hair, blood, liver, also δ 2h and δ 18O values of water from muscle were determined by isotope ratio mass spectrometry. The stable sulfur isotope composition was not affected by cattle variety, meanwhile the hydrogen was uncertain; the δ 2H and δ 34S values between different defatted muscle, blood, liver, cattle hair were significantly different, at the same time the δ 34S and δ 2H values between each tissue were not significantly correlated; the δ 2H values were strongly correlated with the δ 18O values of muscle water. The above results indicated that stable sulfur and hydrogen isotopes fractionation in the various tissues were discrepant, thus the proper tissue should be selected according to the purpose and object in the beef traceability. (authors)

  13. Brain tissue segmentation using q-entropy in multiple sclerosis magnetic resonance images

    Energy Technology Data Exchange (ETDEWEB)

    Diniz, P.R.B.; Brum, D.G. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Dept. de Neurociencias e Ciencias do Comportamento; Santos, A. C. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Dept. de Clinica Medica; Murta-Junior, L.O.; Araujo, D.B. de, E-mail: murta@usp.b [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Fisica e Matematica

    2010-01-15

    The loss of brain volume has been used as a marker of tissue destruction and can be used as an index of the progression of neurodegenerative diseases, such as multiple sclerosis. In the present study, we tested a new method for tissue segmentation based on pixel intensity threshold using generalized Tsallis entropy to determine a statistical segmentation parameter for each single class of brain tissue. We compared the performance of this method using a range of different q parameters and found a different optimal q parameter for white matter, gray matter, and cerebrospinal fluid. Our results support the conclusion that the differences in structural correlations and scale invariant similarities present in each tissue class can be accessed by generalized Tsallis entropy, obtaining the intensity limits for these tissue class separations. In order to test this method, we used it for analysis of brain magnetic resonance images of 43 patients and 10 healthy controls matched for gender and age. The values found for the entropic q index were 0.2 for cerebrospinal fluid, 0.1 for white matter and 1.5 for gray matter. With this algorithm, we could detect an annual loss of 0.98% for the patients, in agreement with literature data. Thus, we can conclude that the entropy of Tsallis adds advantages to the process of automatic target segmentation of tissue classes, which had not been demonstrated previously. (author)

  14. Brain tissue segmentation using q-entropy in multiple sclerosis magnetic resonance images

    Directory of Open Access Journals (Sweden)

    P.R.B. Diniz

    2010-01-01

    Full Text Available The loss of brain volume has been used as a marker of tissue destruction and can be used as an index of the progression of neurodegenerative diseases, such as multiple sclerosis. In the present study, we tested a new method for tissue segmentation based on pixel intensity threshold using generalized Tsallis entropy to determine a statistical segmentation parameter for each single class of brain tissue. We compared the performance of this method using a range of different q parameters and found a different optimal q parameter for white matter, gray matter, and cerebrospinal fluid. Our results support the conclusion that the differences in structural correlations and scale invariant similarities present in each tissue class can be accessed by generalized Tsallis entropy, obtaining the intensity limits for these tissue class separations. In order to test this method, we used it for analysis of brain magnetic resonance images of 43 patients and 10 healthy controls matched for gender and age. The values found for the entropic q index were 0.2 for cerebrospinal fluid, 0.1 for white matter and 1.5 for gray matter. With this algorithm, we could detect an annual loss of 0.98% for the patients, in agreement with literature data. Thus, we can conclude that the entropy of Tsallis adds advantages to the process of automatic target segmentation of tissue classes, which had not been demonstrated previously.

  15. Nanoparticle-enhanced spectral photoacoustic tomography: effect of oxygen saturation and tissue heterogeneity

    Science.gov (United States)

    Vogt, William C.; Jia, Congxian; Wear, Keith A.; Garra, Brian S.; Pfefer, T. Joshua

    2016-03-01

    Molecular imaging for breast cancer detection, infectious disease diagnostics and preclinical animal research may be achievable through combined use of targeted exogenous agents - such as nanoparticles - and spectral Photoacoustic Tomography (PAT). However, tissue heterogeneity can alter fluence distributions and acoustic propagation, corrupting measured PAT absorption spectra and complicating in vivo nanoparticle detection and quantitation. Highly absorptive vascular structures represent a common confounding factor, and variations in vessel hemoglobin saturation (SO2) may alter spectral content of signals from adjacent/deeper regions. To evaluate the impact of this effect on PAT nanoparticle detectability, we constructed heterogeneous phantoms with well-characterized channel-inclusion geometries and biologically relevant optical and acoustic properties. Phantoms contained an array of tubes at several depths filled with hemoglobin solutions doped with varying concentrations of gold nanorods with an absorption peak at 780 nm. Both overlying and target network SO2 was tuned using sodium dithionite. Phantoms were imaged from 700 to 900 nm using a custom PAT system comprised of a tunable pulsed laser and a research-grade ultrasound system. Recovered nanoparticle spectra were analyzed and compared with results from both spectrophotometry and PAT data from waterimmersed tubes containing blood and nanoparticle solutions. Results suggested that nanoparticle selection for a given PAT application should take into account expected oxygenation states of both target blood vessel and background tissue oxygenation to achieve optimal performance.

  16. Effect of ketamine on aquaporin-4 expression and neuronal apoptosis in brain tissues following brain injury in rats

    Institute of Scientific and Technical Information of China (English)

    Zangong Zhou; Xiangyu Ji; Li Song; Jianfang Song; Shiduan Wang; Yanwei Yin

    2006-01-01

    BACKGROUND: Aquaporin-4 (AQP-4) is closely related to the formation of brain edema. Neuronal apoptosis plays an important part in the conversion of swelled neuron following traumatic brain injury. At present, the studies on the protective effect of ketamine on brain have involved in its effect on aquaporin-4 expression and neuronal apoptosis in the brain tissues following brain injury in rats.OBJECTIVE: To observe the effect of ketamine on AQP-4 expression and neuronal apoptosis in the brain tissue following rat brain injury, and analyze the time-dependence of ketamine in the treatment of brain injury.DESIGN: Randomized grouping design, controlled animal trial.SETTING: Department of Anesthesiology, the Medical School Hospital of Qingdao University.MATERIALS: Totally 150 rats of clean grade, aged 3 months, were involved and randomized into control group and ketamine-treated group, with 75 rats in each. Each group was divided into 5 subgroups separately at 6,12, 24, 48 and 72 hours after injury, with 15 rats at each time point. Main instruments and reagents:homemade beat machine, ketamine hydrochloride (Hengrui Pharmaceutical Factory, Jiangsu), rabbit anti-rat AQP-4 polyclonal antibody, SABC immunohistochemical reagent kit and TUNEL reagent kit (Boster Co.,Ltd.,Wuhan).METHODS: This trial was carried out in the Institute of Cerebrovascular Disease, Medical College of Qingdao University during March 2005 to February 2006. A weight-dropping rat model of brain injury was created with Feeney method. The rats in the ketamine-treated group were intraperitoneally administered with 50 g/L ketamine (120 mg/kg) one hour after injury, but ketamine was replaced by normal saline in the control group. In each subgroup, the water content of cerebral hemisphere was measured in 5 rats chosen randomly. The left 10 rats in each subgroup were transcardiacally perfused with ketamine, then the brain tissue was made into paraffin sections and stained by haematoxylin and eosin. Neuronal

  17. Distribution of dearomatised white spirit in brain, blood, and fat tissue after repeated exposure of rats

    DEFF Research Database (Denmark)

    Lof, A.; Lam, Henrik Rye; Gullstrand, E.;

    1999-01-01

    Petroleum products with low content of aromatics have been increasingly used during the past years. This study investigates tissue disposition of dearomatised white spirit. In addition, brain neurotransmitter concentrations were measured. Male rats were exposed by inhalation to 0, 400 (2.29 mg...... spirit was 1.5 and 5.6 mg/kg in blood; 7.1 and 17.1 mg/kg in brain; 432 and 1452 mg/kg in fat tissue at the exposure levels of 400 and 800 p.p.m., respectively. The concentrations of n-nonane, n-decane, n-undecane, and total white spirit in blood and brain were not affected by the duration of exposure....... Two hours after the end of exposure the n-decane concentration decreased to about 25% in blood and 50% in brain. A similar pattern of elimination was also observed for n-nonane, n-undecane and total white spirit in blood and brain. In fat tissue the concentrations of n-nonane, n-decane, n...

  18. Elderly depression diagnostic of diabetic patients by brain tissue pulsatility imaging

    Science.gov (United States)

    Hachemi, Mélouka Elkateb; Remeniéras, Jean-pierre; Desmidt, Thomas; Camus, Vincent; Tranquart, François

    2010-01-01

    Pulsatile motion of brain parenchyma results from cardiac and breathing cycles and consists in a rapid displacement in systole, with slow diastolic recovery. Based on the vascular depression concept and recent studies where a correlation was found between cerebral haemodynamics and depression in the elderly, we emitted the hypothesis that tissue brain motion due to perfusion is correlated to elderly depression associated with cardiovascular risk factors. Tissue Pulsatlity Imaging (TPI) is a new ultrasound technique developed firstly at the University of Washington to assess the brain tissue motion. We used TPI technique to measure the brain displacement of two groups of elderly patients with diabetes as a vascular risk factor. The first group is composed of 11 depressed diabetic patients. The second group is composed of 12 diabetic patients without depressive symptoms. Transcranial acquisitions were performed with a 1.8 MHz ultrasound phased array probe through the right temporal bone window. The acquisition of six cardiac cycles was realized on each patient with a frame rate of 23 frames/s. Displacements estimation was performed by off-line analysis. A significant decrease in brain pulsatility was observed in the group of depressed patients compared to the group of non depressed patients. Mean displacement magnitude was about 44±7 μm in the first group and 68±13 μm in the second group.

  19. Efficient Cargo Delivery into Adult Brain Tissue Using Short Cell-Penetrating Peptides.

    Directory of Open Access Journals (Sweden)

    Caghan Kizil

    Full Text Available Zebrafish brains can regenerate lost neurons upon neurogenic activity of the radial glial progenitor cells (RGCs that reside at the ventricular region. Understanding the molecular events underlying this ability is of great interest for translational studies of regenerative medicine. Therefore, functional analyses of gene function in RGCs and neurons are essential. Using cerebroventricular microinjection (CVMI, RGCs can be targeted efficiently but the penetration capacity of the injected molecules reduces dramatically in deeper parts of the brain tissue, such as the parenchymal regions that contain the neurons. In this report, we tested the penetration efficiency of five known cell-penetrating peptides (CPPs and identified two- polyR and Trans - that efficiently penetrate the brain tissue without overt toxicity in a dose-dependent manner as determined by TUNEL staining and L-Plastin immunohistochemistry. We also found that polyR peptide can help carry plasmid DNA several cell diameters into the brain tissue after a series of coupling reactions using DBCO-PEG4-maleimide-based Michael's addition and azide-mediated copper-free click reaction. Combined with the advantages of CVMI, such as rapidness, reproducibility, and ability to be used in adult animals, CPPs improve the applicability of the CVMI technique to deeper parts of the central nervous system tissues.

  20. Autonomous control for mechanically stable navigation of microscale implants in brain tissue to record neural activity.

    Science.gov (United States)

    Anand, Sindhu; Kumar, Swathy Sampath; Muthuswamy, Jit

    2016-08-01

    Emerging neural prosthetics require precise positional tuning and stable interfaces with single neurons for optimal function over a lifetime. In this study, we report an autonomous control to precisely navigate microscale electrodes in soft, viscoelastic brain tissue without visual feedback. The autonomous control optimizes signal-to-noise ratio (SNR) of single neuronal recordings in viscoelastic brain tissue while maintaining quasi-static mechanical stress conditions to improve stability of the implant-tissue interface. Force-displacement curves from microelectrodes in in vivo rodent experiments are used to estimate viscoelastic parameters of the brain. Using a combination of computational models and experiments, we determined an optimal movement for the microelectrodes with bidirectional displacements of 3:2 ratio between forward and backward displacements and a inter-movement interval of 40 s for minimizing mechanical stress in the surrounding brain tissue. A regulator with the above optimal bidirectional motion for the microelectrodes in in vivo experiments resulted in significant reduction in the number of microelectrode movements (0.23 movements/min) and longer periods of stable SNR (53 % of the time) compared to a regulator using a conventional linear, unidirectional microelectrode movement (with 1.48 movements/min and stable SNR 23 % of the time). PMID:27457752

  1. Polychlorinated biphenyls in adipose tissue, liver, and brain from nine stillborns of varying gestational ages

    NARCIS (Netherlands)

    Huisman, M; Muskiet, FAJ; Van Der Paauw, CG; Essed, CE; Boersma, ER

    1998-01-01

    We analyzed polychlorinated biphenyls (PCBs) in s.c. adipose tissue, liver, and brain of nine fetuses who died in utero. Their median (range) gestational ages and birth weights were 34 (17-40) wk and 2050 (162-3225) g. Three fetuses were small for gestational age. The levels of PCB congener nos. 118

  2. Modeling concentration distribution and deformation during convection-enhanced drug delivery into brain tissue

    NARCIS (Netherlands)

    Støverud, K.; Darcis, M.; Helmig, R.; Hassanizadeh, S.M.

    2012-01-01

    Convection-enhanced drug delivery is a technique where a therapeutic agent is infused under positive pressure directly into the brain tissue. For predicting the final concentration distribution and optimizing infusion rate and catheter placement, numerical models can be of great help. However, despi

  3. Changes in Rat Brain Tissue Microstructure and Stiffness during the Development of Experimental Obstructive Hydrocephalus.

    Directory of Open Access Journals (Sweden)

    Lauriane Jugé

    Full Text Available Understanding neural injury in hydrocephalus and how the brain changes during the course of the disease in-vivo remain unclear. This study describes brain deformation, microstructural and mechanical properties changes during obstructive hydrocephalus development in a rat model using multimodal magnetic resonance (MR imaging. Hydrocephalus was induced in eight Sprague-Dawley rats (4 weeks old by injecting a kaolin suspension into the cisterna magna. Six sham-injected rats were used as controls. MR imaging (9.4T, Bruker was performed 1 day before, and at 3, 7 and 16 days post injection. T2-weighted MR images were collected to quantify brain deformation. MR elastography was used to measure brain stiffness, and diffusion tensor imaging (DTI was conducted to observe brain tissue microstructure. Results showed that the enlargement of the ventricular system was associated with a decrease in the cortical gray matter thickness and caudate-putamen cross-sectional area (P < 0.001, for both, an alteration of the corpus callosum and periventricular white matter microstructure (CC+PVWM and rearrangement of the cortical gray matter microstructure (P < 0.001, for both, while compression without gross microstructural alteration was evident in the caudate-putamen and ventral internal capsule (P < 0.001, for both. During hydrocephalus development, increased space between the white matter tracts was observed in the CC+PVWM (P < 0.001, while a decrease in space was observed for the ventral internal capsule (P < 0.001. For the cortical gray matter, an increase in extracellular tissue water was significantly associated with a decrease in tissue stiffness (P = 0.001. To conclude, this study characterizes the temporal changes in tissue microstructure, water content and stiffness in different brain regions and their association with ventricular enlargement. In summary, whilst diffusion changes were larger and statistically significant for majority of the brain regions

  4. PIXE analysis of low concentration aluminum in brain tissues of an Alzheimer's disease patient

    International Nuclear Information System (INIS)

    An excess accumulation and presence of metal ions may significantly alter a brain cell's normal functions. There have been increasing efforts in recent years to measure and quantify the density and distribution of excessive accumulations of constituent elements (such as Fe, Zn, Cu, and Ca) in the brain, as well as the presence and distribution of contaminating elements (such as Al). This is particularly important in cases of neuropathological disorders such as Alzheimer's disease, Parkinson's disease and ALS. The aim of this paper was to measure the Al present in the temporal cortex of the brain of an Alzheimer's disease patient. The specimens were taken from an unfixed autopsy brain which has been preserved for a period of 4 years in the deep freezer at -80 degree sign C. Proton Induced X-ray Emission Spectroscopy was used for the measurement of Al concentration in this brain tissue. A tandem accelerator with 2 MeV of energy was also used. In order to increase the sensitivity of the signals in the low energy region of the spectra, the absorbers were removed. The results show that the peak height depends on the measurement site. However, in certain cases an extremely high concentration of Al was observed in the PIXE spectra, with an intensity higher than those in the other major elements of the brain's matrix element. Samples from tissues affected by the same disease were analyzed using the EDX analyzer. The results are quantitatively in very good agreement with those of the PIXE analysis

  5. Computational Assessment of Neural Probe and Brain Tissue Interface under Transient Motion

    Directory of Open Access Journals (Sweden)

    Michael Polanco

    2016-06-01

    Full Text Available The functional longevity of a neural probe is dependent upon its ability to minimize injury risk during the insertion and recording period in vivo, which could be related to motion-related strain between the probe and surrounding tissue. A series of finite element analyses was conducted to study the extent of the strain induced within the brain in an area around a neural probe. This study focuses on the transient behavior of neural probe and brain tissue interface with a viscoelastic model. Different stages of the interface from initial insertion of neural probe to full bonding of the probe by astro-glial sheath formation are simulated utilizing analytical tools to investigate the effects of relative motion between the neural probe and the brain while friction coefficients and kinematic frequencies are varied. The analyses can provide an in-depth look at the quantitative benefits behind using soft materials for neural probes.

  6. Multisite Tissue Oxygenation Monitoring Indicates Organ-Specific Flow Distribution and Oxygen Delivery Related to Low Cardiac Output in Preterm Infants With Clinical Sepsis

    NARCIS (Netherlands)

    van der Laan, Michelle E; Roofthooft, Marc; Fries, Marian W A; Schat, Trijntje E; Bos, Arend F; Berger, Rolf M F; Kooi, Elisabeth M W

    2016-01-01

    OBJECTIVES: Cardiac output may be compromised in preterm infants with sepsis. Whether low cardiac output is associated with low tissue oxygen supply in these patients is unclear. The aim of the current study was to assess the association between cardiac output, assessed by echocardiography, and tiss

  7. An analytical model for nanoparticles concentration resulting from infusion into poroelastic brain tissue.

    Science.gov (United States)

    Pizzichelli, G; Di Michele, F; Sinibaldi, E

    2016-02-01

    We consider the infusion of a diluted suspension of nanoparticles (NPs) into poroelastic brain tissue, in view of relevant biomedical applications such as intratumoral thermotherapy. Indeed, the high impact of the related pathologies motivates the development of advanced therapeutic approaches, whose design also benefits from theoretical models. This study provides an analytical expression for the time-dependent NPs concentration during the infusion into poroelastic brain tissue, which also accounts for particle binding onto cells (by recalling relevant results from the colloid filtration theory). Our model is computationally inexpensive and, compared to fully numerical approaches, permits to explicitly elucidate the role of the involved physical aspects (tissue poroelasticity, infusion parameters, NPs physico-chemical properties, NP-tissue interactions underlying binding). We also present illustrative results based on parameters taken from the literature, by considering clinically relevant ranges for the infusion parameters. Moreover, we thoroughly assess the model working assumptions besides discussing its limitations. While not laying any claims of generality, our model can be used to support the development of more ambitious numerical approaches, towards the preliminary design of novel therapies based on NPs infusion into brain tissue. PMID:26656677

  8. Spatial mapping of drug delivery to brain tissue using hyperspectral spatial frequency-domain imaging

    Science.gov (United States)

    Singh-Moon, Rajinder P.; Roblyer, Darren M.; Bigio, Irving J.; Joshi, Shailendra

    2014-09-01

    We present an application of spatial frequency-domain imaging (SFDI) to the wide-field imaging of drug delivery to brain tissue. Measurements were compared with values obtained by a previously validated variation of diffuse reflectance spectroscopy, the method of optical pharmacokinetics (OP). We demonstrate a cross-correlation between the two methods for absorption extraction and drug concentration determination in both experimental tissue phantoms and freshly extracted rodent brain tissue. These methods were first used to assess intra-arterial (IA) delivery of cationic liposomes to brain tissue in Sprague Dawley rats under transient cerebral hypoperfusion. Results were found to be in agreement with previously published experimental data and pharmacokinetic models of IA drug delivery. We then applied the same scheme to evaluate IA mitoxantrone delivery to glioma-bearing rats. Good correlation was seen between OP and SFDI determined concentrations taken from normal and tumor averaged sites. This study shows the feasibility of mapping drug/tracer distributions and encourages the use of SFDI for spatial imaging of tissues for drug/tracer-tagged carrier deposition and pharmacokinetic studies.

  9. DNA extraction from fresh-frozen and formalin-fixed, paraffin-embedded human brain tissue.

    Science.gov (United States)

    Wang, Jian-Hua; Gouda-Vossos, Amany; Dzamko, Nicolas; Halliday, Glenda; Huang, Yue

    2013-10-01

    Both fresh-frozen and formalin-fixed, paraffin-embedded (FFPE) human brain tissues are invaluable resources for molecular genetic studies of central nervous system diseases, especially neurodegenerative disorders. To identify the optimal method for DNA extraction from human brain tissue, we compared methods on differently-processed tissues. Fragments of LRRK2 and MAPT (257 bp and 483 bp/245 bp) were amplified for evaluation. We found that for FFPE samples, the success rate of DNA extraction was greater when using a commercial kit than a laboratory-based method (successful DNA extraction from 76% versus 33% of samples). PCR amplicon size and storage period were key factors influencing the success rate of DNA extraction from FFPE samples. In the fresh-frozen samples, the DNA extraction success rate was 100% using either a commercial kit (QIAamp DNA Micro) or a laboratory-based method (sample boiling in 0.1 mol/L NaOH, followed by proteinase K digestion, and then DNA extraction using Chelex-100) regardless of PCR amplicon length or tissue storage time. Although the present results demonstrate that PCR-amplifiable genomic DNA can be extracted from both fresh-frozen and FFPE samples, fresh brain tissue is recommended for DNA extraction in future neuropathological studies.

  10. Effect of ketamine on aquaporin-4 expression and neuronal apoptosis in brain tissues following brain injury in rats

    Institute of Scientific and Technical Information of China (English)

    Zangong Zhou; Xiangyu Ji; Li Song; Jianfang Song; Shiduan Wang; Yanwei Yin

    2006-01-01

    BACKGROUND: Aquaporin-4 (AQP-4) is closely related to the formation of brain edema. Neuronal apoptosis plays an important part in the conversion of swelled neuron following traumatic brain injury. At present, the studies on the protective effect of ketamine on brain have involved in its effect on aquaporin-4 expression and neuronal apoptosis in the brain tissues following brain injury in rats.OBJECTIVE: To observe the effect of ketamine on AQP-4 expression and neuronal apoptosis in the brain tissue following rat brain injury, and analyze the time-dependence of ketamine in the treatment of brain injury.DESIGN: Randomized grouping design, controlled animal trial.SETTING: Department of Anesthesiology, the Medical School Hospital of Qingdao University.MATERIALS: Totally 150 rats of clean grade, aged 3 months, were involved and randomized into control group and ketamine-treated group, with 75 rats in each. Each group was divided into 5 subgroups separately at 6,12, 24, 48 and 72 hours after injury, with 15 rats at each time point. Main instruments and reagents:homemade beat machine, ketamine hydrochloride (Hengrui Pharmaceutical Factory, Jiangsu), rabbit anti-rat AQP-4 polyclonal antibody, SABC immunohistochemical reagent kit and TUNEL reagent kit (Boster Co.,Ltd.,Wuhan).METHODS: This trial was carried out in the Institute of Cerebrovascular Disease, Medical College of Qingdao University during March 2005 to February 2006. A weight-dropping rat model of brain injury was created with Feeney method. The rats in the ketamine-treated group were intraperitoneally administered with 50 g/L ketamine (120 mg/kg) one hour after injury, but ketamine was replaced by normal saline in the control group. In each subgroup, the water content of cerebral hemisphere was measured in 5 rats chosen randomly. The left 10 rats in each subgroup were transcardiacally perfused with ketamine, then the brain tissue was made into paraffin sections and stained by haematoxylin and eosin. Neuronal

  11. Distribution of soya-saponin in brain and peripheral tissue after peritoneal injection

    International Nuclear Information System (INIS)

    125I-soya-saponin was prepared to study the distribution of soya-saponin in body of rat, as well as in different areas of brain when peritoneal injection. The results showed that the peak value of radioactive soya-saponin in all tissue appeared at 30 min after peritoneal injection. There were higher radioactivities in brain and suprarene comparing with other organs. The highest radioactivity was seen in hypothalamus among the every brain areas. It is a first report that soyasaponin can pass through the blood brain barrier when peripheral injection. The result also supported the opinion that soyasaponin might act on the hypothalamus and central regulation of cardiovascular system. Another finding was that soyasaponin also showed a higher affinity with adrenal gland, which indicated that the soyasaponin might possess of peripheral effect for regulation of cardiovascular system as well

  12. Evaluation of Raman spectra of human brain tumor tissue using the learning vector quantization neural network

    Science.gov (United States)

    Liu, Tuo; Chen, Changshui; Shi, Xingzhe; Liu, Chengyong

    2016-05-01

    The Raman spectra of tissue of 20 brain tumor patients was recorded using a confocal microlaser Raman spectroscope with 785 nm excitation in vitro. A total of 133 spectra were investigated. Spectra peaks from normal white matter tissue and tumor tissue were analyzed. Algorithms, such as principal component analysis, linear discriminant analysis, and the support vector machine, are commonly used to analyze spectral data. However, in this study, we employed the learning vector quantization (LVQ) neural network, which is typically used for pattern recognition. By applying the proposed method, a normal diagnosis accuracy of 85.7% and a glioma diagnosis accuracy of 89.5% were achieved. The LVQ neural network is a recent approach to excavating Raman spectra information. Moreover, it is fast and convenient, does not require the spectra peak counterpart, and achieves a relatively high accuracy. It can be used in brain tumor prognostics and in helping to optimize the cutting margins of gliomas.

  13. Low temperature magnetic analysis in the identification of iron compounds from human brain tumour tissue

    Energy Technology Data Exchange (ETDEWEB)

    Brem, F [Institute of Geophysics, ETH-Hoenggerberg, CH-8093 Zurich (Switzerland); Hirt, A M [Institute of Geophysics, ETH-Hoenggerberg, CH-8093 Zurich (Switzerland); Simon, C [Neurology/EEG, University Hospital Zurich, CH-8091 Zurich (Switzerland); Wieser, H-G [Neurology/EEG, University Hospital Zurich, CH-8091 Zurich (Switzerland); Dobson, J [Institute for Science and Technology in Medicine, Keele University, Stoke-on-Trent, ST4 7QB, (United Kingdom)

    2005-01-01

    In the brain, iron plays an important role, but also is potentially toxic if iron metabolism is disrupted. Excess iron accumulation in the brain has been shown to be associated with neurodegenerative diseases. However, identification of iron compounds in human tissue is difficult because concentrations are very low. Three types of magnetic methods were used to characterize iron compounds in tumour tissue from epileptic patients. Isothermal Remanent Magnetization (IRM) was measured at 77 K and 300 K and reveals a low-coercivity phase with the properties of magnetite or maghemite. Induced magnetization was measured between 2 K and 300 K after cooling in zero-field and in a 50 mT field. These curves reveal an average blocking temperature of 11 K, which is compatible with ferritin. The results of this study show that the combination of different magnetic methods provides a useful and sensitive tool for the characterisation of magnetic iron compounds in human tissue.

  14. A Simplified Workflow for Protein Quantitation of Rat Brain Tissues Using Label-Free Proteomics and Spectral Counting.

    Science.gov (United States)

    Boutté, Angela M; Grant, Shonnette F; Dave, Jitendra R

    2016-01-01

    Mass spectrometry-based proteomics is an increasingly valuable tool for determining relative or quantitative protein abundance in brain tissues. A plethora of technical and analytical methods are available, but straightforward and practical approaches are often needed to facilitate reproducibility. This aspect is particularly important as an increasing number of studies focus on models of traumatic brain injury or brain trauma, for which brain tissue proteomes have not yet been fully described. This text provides suggested techniques for robust identification and quantitation of brain proteins by using molecular weight fractionation prior to mass spectrometry-based proteomics. Detailed sample preparation and generalized protocols for chromatography, mass spectrometry, spectral counting, and normalization are described. The rat cerebral cortex isolated from a model of blast-overpressure was used as an exemplary source of brain tissue. However, these techniques may be adapted for lysates generated from several types of cells or tissues and adapted by the end user.

  15. Mapping drug distribution in brain tissue using liquid extraction surface analysis mass spectrometry imaging.

    Science.gov (United States)

    Swales, John G; Tucker, James W; Spreadborough, Michael J; Iverson, Suzanne L; Clench, Malcolm R; Webborn, Peter J H; Goodwin, Richard J A

    2015-10-01

    Liquid extraction surface analysis mass spectrometry (LESA-MS) is a surface sampling technique that incorporates liquid extraction from the surface of tissue sections with nanoelectrospray mass spectrometry. Traditional tissue analysis techniques usually require homogenization of the sample prior to analysis via high-performance liquid chromatography mass spectrometry (HPLC-MS), but an intrinsic weakness of this is a loss of all spatial information and the inability of the technique to distinguish between actual tissue penetration and response caused by residual blood contamination. LESA-MS, in contrast, has the ability to spatially resolve drug distributions and has historically been used to profile discrete spots on the surface of tissue sections. Here, we use the technique as a mass spectrometry imaging (MSI) tool, extracting points at 1 mm spatial resolution across tissue sections to build an image of xenobiotic and endogenous compound distribution to assess drug blood-brain barrier penetration into brain tissue. A selection of penetrant and "nonpenetrant" drugs were dosed to rats via oral and intravenous administration. Whole brains were snap-frozen at necropsy and were subsequently sectioned prior to analysis by matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) and LESA-MSI. MALDI-MSI, as expected, was shown to effectively map the distribution of brain penetrative compounds but lacked sufficient sensitivity when compounds were marginally penetrative. LESA-MSI was used to effectively map the distribution of these poorly penetrative compounds, highlighting its value as a complementary technique to MALDI-MSI. The technique also showed benefits when compared to traditional homogenization, particularly for drugs that were considered nonpenetrant by homogenization but were shown to have a measurable penetration using LESA-MSI. PMID:26350423

  16. Static jaw collimation settings to minimize radiation dose to normal brain tissue during stereotactic radiosurgery.

    Science.gov (United States)

    Han, Eun Young; Zhang, Xin; Yan, Yulong; Sharma, Sunil; Penagaricano, Jose; Moros, Eduardo; Corry, Peter

    2012-01-01

    At the University of Arkansas for Medical Sciences (UAMS) intracranial stereotactic radiosurgery (SRS) is performed by using a linear accelerator with an add-on micromultileaf collimator (mMLC). In our clinical setting, static jaws are automatically adapted to the furthest edge of the mMLC-defined segments with 2-mm (X jaw) and 5-mm (Y jaw) margin and the same jaw values are applied for all beam angles in the treatment planning system. This additional field gap between the static jaws and the mMLC allows additional radiation dose to normal brain tissue. Because a radiosurgery procedure consists of a single high dose to the planning target volume (PTV), reduction of unnecessary dose to normal brain tissue near the PTV is important, particularly for pediatric patients whose brains are still developing or when a critical organ, such as the optic chiasm, is near the PTV. The purpose of this study was to minimize dose to normal brain tissue by allowing minimal static jaw margin around the mMLC-defined fields and different static jaw values for each beam angle or arc. Dose output factors were measured with various static jaw margins and the results were compared with calculated doses in the treatment planning system. Ten patient plans were randomly selected and recalculated with zero static jaw margins without changing other parameters. Changes of PTV coverage, mean dose to predefined normal brain tissue volume adjacent to PTV, and monitor units were compared. It was found that the dose output percentage difference varied from 4.9-1.3% for the maximum static jaw opening vs. static jaw with zero margins. The mean dose to normal brain tissue at risk adjacent to the PTV was reduced by an average of 1.9%, with negligible PTV coverage loss. This dose reduction strategy may be meaningful in terms of late effects of radiation, particularly in pediatric patients. This study generated clinical knowledge and tools to consistently minimize dose to normal brain tissue.

  17. Vascular Steal Explains Early Paradoxical Blood Oxygen Level-Dependent Cerebrovascular Response in Brain Regions with Delayed Arterial Transit Times

    Directory of Open Access Journals (Sweden)

    Julien Poublanc

    2013-04-01

    Full Text Available Introduction: Blood oxygen level-dependent (BOLD magnetic resonance imaging (MRI during manipulation of inhaled carbon dioxide (CO2 can be used to measure cerebrovascular reactivity (CVR and map regions of exhausted cerebrovascular reserve. These regions exhibit a reduced or negative BOLD response to inhaled CO2. In this study, we sought to clarify the mechanism behind the negative BOLD response by investigating its time delay (TD. Dynamic susceptibility contrast (DSC MRI with the injection of a contrast agent was used as the gold standard in order to provide measurement of the blood arrival time to which CVR TD could be compared. We hypothesize that if negative BOLD responses are the result of a steal phenomenon, they should be synchronized with positive BOLD responses from healthy brain tissue, even though the blood arrival time would be delayed. Methods: On a 3-tesla MRI system, BOLD CVR and DSC images were collected in a group of 19 patients with steno-occlusive cerebrovascular disease. For each patient, we generated a CVR magnitude map by regressing the BOLD signal with the end-tidal partial pressure of CO2 (PETCO2, and a CVR TD map by extracting the time of maximum cross-correlation between the BOLD signal and PETCO2. In addition, a blood arrival time map was generated by fitting the DSC signal with a gamma variate function. ROI masks corresponding to varying degrees of reactivity were constructed. Within these masks, the mean CVR magnitude, CVR TD and DSC blood arrival time were extracted and averaged over the 19 patients. CVR magnitude and CVR TD were then plotted against DSC blood arrival time. Results: The results show that CVR magnitude is highly correlated to DSC blood arrival time. As expected, the most compromised tissues with the longest blood arrival time have the lowest (most negative CVR magnitude. However, CVR TD shows a noncontinuous relationship with DSC blood arrival time. CVR TD is well correlated to DSC blood arrival time

  18. The Importance of Brain Banks for Molecular Neuropathological Research: The New South Wales Tissue Resource Centre Experience

    Directory of Open Access Journals (Sweden)

    Antony Harding

    2009-01-01

    Full Text Available New developments in molecular neuropathology have evoked increased demands for postmortem human brain tissue. The New South Wales Tissue Resource Centre (TRC at The University of Sydney has grown from a small tissue collection into one of the leading international brain banking facilities, which operates with best practice and quality control protocols. The focus of this tissue collection is on schizophrenia and allied disorders, alcohol use disorders and controls. This review highlights changes in TRC operational procedures dictated by modern neuroscience, and provides examples of applications of modern molecular techniques to study the neuropathogenesis of many different brain disorders.

  19. The cerebrovascular structure and brain tissue volume: a comparative study between beagle dogs and mongrel dogs

    International Nuclear Information System (INIS)

    Objective: To compare the differences of cerebrovascular structure and brain tissue volume between beagle and mongrel dogs by using angiography and MR scanning. Methods: A total of 40 dogs, including 20 beagle dogs (beagle group) and 20 mongrel dogs (mongrel group), were enrolled in this study. Under general anesthesia, all dogs were examined with cerebral angiography and MR scanning. The cerebrovascular structure was evaluated with angiography via selective catheterization of aortic arch, bilateral external cerebral arteries (ECA), maxillary arteries, internal cerebral arteries (ICA) and vertebral arteries separately. The diameters of the ICA, middle cerebral artery (MCA), rostral cerebral artery (RCA), the anastomosis channel ICA and ECA, and basilar artery (BA) were measured at the similar point of each dog. Meanwhile the volumes of the brain tissue were calculated in coronal T2 view of MR scanning. The statistical analysis was performed among the weight of dogs, the diameter of arteries and the volume of brain tissue. The differences in the diameters and brain tissue volume were compared between the two groups. Results: No obvious variations in the cerebrovascular structure and brain tissue volume were found in these dogs. One mongrel dog was excluded from this study because of the severe stenosis of ICA. The mean weight of 20 beagle dogs and 19 mongrel dogs was (12.81±1.29) kg and (12.85±1.12) kg, respectively. The diameters of the ICA, MCA, RCA, the anastomosis channel between ICA and ECA and BA in beagle group were (1.26±0.07) mm, (0.90±0.05) mm, (0.58±0.07) mm, (0.55±0.07) mm and (0.95±0.06) mm, respectively. These parameters in mongrel group were (1.27±0.07) mm, (0.92±0.05) mm, (0.59±0.06) mm, (0.67±0.07) mm and (0.94±0.05) mm, respectively. The volume of brain in two groups was (76232.33±5018.51) mm3 and (71863.96±4626.87) mm3, respectively. There were no obvious correlation among the body weight, the cerebrovascular diameters and brain

  20. Global brain blood-oxygen level responses to autonomic challenges in obstructive sleep apnea.

    Directory of Open Access Journals (Sweden)

    Paul M Macey

    Full Text Available Obstructive sleep apnea (OSA is accompanied by brain injury, perhaps resulting from apnea-related hypoxia or periods of impaired cerebral perfusion. Perfusion changes can be determined indirectly by evaluation of cerebral blood volume and oxygenation alterations, which can be measured rapidly and non-invasively with the global blood oxygen level dependent (BOLD signal, a magnetic resonance imaging procedure. We assessed acute BOLD responses in OSA subjects to pressor challenges that elicit cerebral blood flow changes, using a two-group comparative design with healthy subjects as a reference. We separately assessed female and male patterns, since OSA characteristics and brain injury differ between sexes. We studied 94 subjects, 37 with newly-diagnosed, untreated OSA (6 female (age mean ± std: 52.1±8.1 yrs; apnea/hypopnea index [AHI]: 27.7±15.6 events/hr and 31 male 54.3±8.4 yrs; AHI: 37.4±19.6 events/hr, and 20 female (age 50.5±8.1 yrs and 37 male (age 45.6±9.2 yrs healthy control subjects. We measured brain BOLD responses every 2 s while subjects underwent cold pressor, hand grip, and Valsalva maneuver challenges. The global BOLD signal rapidly changed after the first 2 s of each challenge, and differed in magnitude between groups to two challenges (cold pressor, hand grip, but not to the Valsalva maneuver (repeated measures ANOVA, p<0.05. OSA females showed greater differences from males in response magnitude and pattern, relative to healthy counterparts. Cold pressor BOLD signal increases (mean ± adjusted standard error at the 8 s peak were: OSA 0.14±0.08% vs. Control 0.31±0.06%, and hand grip at 6 s were: OSA 0.08±0.03% vs. Control at 0.30±0.02%. These findings, indicative of reduced cerebral blood flow changes to autonomic challenges in OSA, complement earlier reports of altered resting blood flow and reduced cerebral artery responsiveness. Females are more affected than males, an outcome which may contribute to the sex

  1. The average baboon brain: MRI templates and tissue probability maps from 89 individuals.

    Science.gov (United States)

    Love, Scott A; Marie, Damien; Roth, Muriel; Lacoste, Romain; Nazarian, Bruno; Bertello, Alice; Coulon, Olivier; Anton, Jean-Luc; Meguerditchian, Adrien

    2016-05-15

    The baboon (Papio) brain is a remarkable model for investigating the brain. The current work aimed at creating a population-average baboon (Papio anubis) brain template and its left/right hemisphere symmetric version from a large sample of T1-weighted magnetic resonance images collected from 89 individuals. Averaging the prior probability maps output during the segmentation of each individual also produced the first baboon brain tissue probability maps for gray matter, white matter and cerebrospinal fluid. The templates and the tissue probability maps were created using state-of-the-art, freely available software tools and are being made freely and publicly available: http://www.nitrc.org/projects/haiko89/ or http://lpc.univ-amu.fr/spip.php?article589. It is hoped that these images will aid neuroimaging research of the baboon by, for example, providing a modern, high quality normalization target and accompanying standardized coordinate system as well as probabilistic priors that can be used during tissue segmentation. PMID:26975558

  2. Elemental analysis of the frontal lobe of 'normal' brain tissue and that affected by Alzheimer's disease

    International Nuclear Information System (INIS)

    'Normal' brain tissue and brain tissue affected by Alzheimer's disease has been taken from the frontal lobe of both hemispheres and their elemental compositions in terms of major, minor and trace elements compared. Brain samples were obtained from the MRC Alzheimer's Disease Brain Bank, London. 25 samples were taken from 18 individuals (5 males and 13 females) of mean age 79.9 ± 7.3 years with pathologically confirmed Alzheimer's disease and 26 samples from 15 individuals (8 males and 7 females) of mean age 71.8 ± 13.0 years with no pathological sings of Alzheimer's disease ('normals'). The elemental concentration of the samples were determined by the techniques of Rutherford backscattering (RBS) analysis, particle induced X-ray emission (PIXE) analysis and instrumental neutron activation analysis (INAA). Na, Mg, Al, Cl, K, Sc, Fe, Zn, Se, Br, Rb and Cs were detected by INAA and significant differences in concentrations were found between concentrations in normal and Alzheimer tissue for the elements. Na, Cl, K, Se, Br and Rb, P, S, Cl, K, Ca, Fe, Zn and Cd were detected by PIXE analysis and significant differences found for the elements P, S, Cl, K and Ca. (author)

  3. X-ray fluorescence analysis in application for study of human brain tissue and body fluids

    International Nuclear Information System (INIS)

    Thin slices of human brain tissue and body fluids were investigated using Energy Dispersive X-Ray Fluorescence (EDXRF) spectrometry. Distribution of elements in brain tissue samples was studied using Microbeam X-Ray Fluorescence (MXRF) method. Total Reflection X-Ray fluorescence (TXRF) analysis was applied for determination of elemental contens in cerebrospinal fluid, serum and whole blood. The main goal of the study was to optimize analytical procedures for investigation of biomedical specimens using EDXRF method. MXRF method is useful for investigation of P, S, Cl, K, Ca and Fe. Moreover, it can be also applied for distinguishing between white and gray matter of the human brain. Two sample preparation methods were applied in TXRF spectrometry with respect to detection limit. In the first method the body fluids were analysed without any sample preparation. The other measurements were performed for the body fluids digested with nitric acid. For both methods gallium was used as an internal standard. Accuracy of the TXRF method was assessed using Certified Reference Material, A-13 (freeze-dried animal blood). High sensitivity of TXRF and proper sample preparation allowed to detect wide spectrum of elements between Cl and Sr. Faster and easier first sample preparation method allowed to detect elements including volatile ones like Cl or Br whereas digestion of fluids with nitric acid improved the detection limits significantly. Elemental analysis of thin brain tissue samples and body fluids will be applied for study of role of trace elements in selected neurological diseases. (author)

  4. Glioblastoma, brain metastases and soft tissue sarcoma of extremities: Candidate tumors for BNCT

    International Nuclear Information System (INIS)

    10B-concentration ratios between human glioblastoma multiforme (U87MG), sarcoma (S3) and melanoma (MV3) xenografted in nu/nu mice and selected normal tissues were investigated to test for preferential 10B-accumulation. Animals received BSH, BPA or both compounds sequentially. Mean 10B-concentration ratios between tumor and normal tissues above 2 were found indicating therapeutic ratios. In addition to glioblastoma, brain metastases and soft tissue sarcoma appear to be promising targets for future BNCT research. - Highlights: • BSH leads to high 10B concentration ratios between sarcoma, muscle and brain as well as between glioblastoma and brain. • The 10B concentration in tumors is quite low as is the 10B concentration ratio between tumors and blood. • BPA-f leads to 10B accumulation in tumors relative to blood and advantageous absolute 10B concentrations in tumors. • The 10B concentration ratios between tumors and brain and sarcoma and muscle, are modest. • The advantage of the sequential injection of both compounds is an enhanced intratumoral 10B concentration

  5. Non-Invasive, Simultaneous Quantification of Vascular Oxygenation and Glucose Uptake in Tissue

    Science.gov (United States)

    Rajaram, Narasimhan; Reesor, Andrew F.; Mulvey, Christine S.; Frees, Amy E.; Ramanujam, Nirmala

    2015-01-01

    We report the development of non-invasive, fiber-based diffuse optical spectroscopy for simultaneously quantifying vascular oxygenation (SO2) and glucose uptake in solid tumors in vivo. Glucose uptake was measured using a fluorescent glucose analog, 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-yl)amino]-2-deoxyglucose (2-NBDG). Quantification of label-free SO2 and 2-NBDG-fluorescence-based glucose uptake 60 minutes after administration of the tracer (2-NBDG60) was performed using computational models of light-tissue interaction. This study was carried out on normal tissue and 4T1 and 4T07 murine mammary tumor xenografts in vivo. Injection of 2-NBDG did not cause a significant change in optical measurements of SO2, demonstrating its suitability as a functional reporter of tumor glucose uptake. Correction of measured 2-NBDG-fluorescence for the effects of absorption and scattering significantly improved contrast between tumor and normal tissue. The 4T1 and 4T07 tumors showed significantly decreased SO2, and 4T1 tumors demonstrated increased 2-NBDG60 compared with normal tissue (60 minutes after the administration of 2-NBDG when perfusion-mediated effects have cleared). 2-NBDG-fluorescence was found to be highly sensitive to food deprivation-induced reduction in blood glucose levels, demonstrating that this endpoint is indeed sensitive to glycolytic demand. 2-NBDG60 was also found to be linearly related to dose, underscoring the importance of calibrating for dose when comparing across animals or experiments. 4T1 tumors demonstrated an inverse relationship between 2-NBDG60 and SO2 that was consistent with the Pasteur effect, particularly when exposed to hypoxic gas breathing. Our results illustrate the potential of optical spectroscopy to provide valuable information about the metabolic status of tumors, with important implications for cancer prognosis. PMID:25635865

  6. Non-invasive, simultaneous quantification of vascular oxygenation and glucose uptake in tissue.

    Directory of Open Access Journals (Sweden)

    Narasimhan Rajaram

    Full Text Available We report the development of non-invasive, fiber-based diffuse optical spectroscopy for simultaneously quantifying vascular oxygenation (SO2 and glucose uptake in solid tumors in vivo. Glucose uptake was measured using a fluorescent glucose analog, 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-ylamino]-2-deoxyglucose (2-NBDG. Quantification of label-free SO2 and 2-NBDG-fluorescence-based glucose uptake 60 minutes after administration of the tracer (2-NBDG60 was performed using computational models of light-tissue interaction. This study was carried out on normal tissue and 4T1 and 4T07 murine mammary tumor xenografts in vivo. Injection of 2-NBDG did not cause a significant change in optical measurements of SO2, demonstrating its suitability as a functional reporter of tumor glucose uptake. Correction of measured 2-NBDG-fluorescence for the effects of absorption and scattering significantly improved contrast between tumor and normal tissue. The 4T1 and 4T07 tumors showed significantly decreased SO2, and 4T1 tumors demonstrated increased 2-NBDG60 compared with normal tissue (60 minutes after the administration of 2-NBDG when perfusion-mediated effects have cleared. 2-NBDG-fluorescence was found to be highly sensitive to food deprivation-induced reduction in blood glucose levels, demonstrating that this endpoint is indeed sensitive to glycolytic demand. 2-NBDG60 was also found to be linearly related to dose, underscoring the importance of calibrating for dose when comparing across animals or experiments. 4T1 tumors demonstrated an inverse relationship between 2-NBDG60 and SO2 that was consistent with the Pasteur effect, particularly when exposed to hypoxic gas breathing. Our results illustrate the potential of optical spectroscopy to provide valuable information about the metabolic status of tumors, with important implications for cancer prognosis.

  7. 99mTc-ECD brain perfusion SPECT imaging for the assessment of brain perfusion in cerebral palsy (CP) patients with evaluation of the effect of hyperbaric oxygen therapy

    OpenAIRE

    Asl, Mina Taghizadeh; Yousefi, Farzaneh; Nemati, Reza; Assadi, Majid

    2015-01-01

    Objective: The present study was carried out to evaluate cerebral perfusion in different types of cerebral palsy (CP) patients. For those patients who underwent hyperbaric oxygen therapy, brain perfusion before and after the therapy was compared. Methods: A total of 11 CP patients were enrolled in this study, of which 4 patients underwent oxygen therapy. Before oxygen therapy and at the end of 40 sessions of oxygen treatment, 99mTc-ECD brain perfusion single photon emission computed tomograph...

  8. Chronic tissue response to untethered microelectrode implants in the rat brain and spinal cord

    Science.gov (United States)

    Ersen, Ali; Elkabes, Stella; Freedman, David S.; Sahin, Mesut

    2015-02-01

    Objective. Microelectrodes implanted in the central nervous system (CNS) often fail in long term implants due to the immunological tissue response caused by tethering forces of the connecting wires. In addition to the tethering effect, there is a mechanical stress that occurs at the device-tissue interface simply because the microelectrode is a rigid body floating in soft tissue and it cannot reshape itself to comply with changes in the surrounding tissue. In the current study we evaluated the scar tissue formation to tetherless devices with two significantly different geometries in the rat brain and spinal cord in order to investigate the effects of device geometry. Approach. One of the implant geometries resembled the wireless, floating microstimulators that we are currently developing in our laboratory and the other was a (shank only) Michigan probe for comparison. Both electrodes were implanted into either the cervical spinal cord or the motor cortices, one on each side. Main results. The most pronounced astroglial and microglial reactions occurred within 20 μm from the device and decreased sharply at larger distances. Both cell types displayed the morphology of non-activated cells past the 100 μm perimeter. Even though the aspect ratios of the implants were different, the astroglial and microglial responses to both microelectrode types were very mild in the brain, stronger and yet limited in the spinal cord. Significance. These observations confirm previous reports and further suggest that tethering may be responsible for most of the tissue response in chronic implants and that the electrode size has a smaller contribution with floating electrodes. The electrode size may be playing primarily an amplifying role to the tethering forces in the brain whereas the size itself may induce chronic response in the spinal cord where the movement of surrounding tissues is more significant.

  9. Repetitive Hyperbaric Oxygenation Attenuates Reactive Astrogliosis and Suppresses Expression of Inflammatory Mediators in the Rat Model of Brain Injury

    Directory of Open Access Journals (Sweden)

    Irena Lavrnja

    2015-01-01

    Full Text Available The exact mechanisms by which treatment with hyperbaric oxygen (HBOT exerts its beneficial effects on recovery after brain injury are still unrevealed. Therefore, in this study we investigated the influence of repetitive HBOT on the reactive astrogliosis and expression of mediators of inflammation after cortical stab injury (CSI. CSI was performed on male Wistar rats, divided into control, sham, and lesioned groups with appropriate HBO. The HBOT protocol was as follows: 10 minutes of slow compression, 2.5 atmospheres absolute (ATA for 60 minutes, and 10 minutes of slow decompression, once a day for 10 consecutive days. Data obtained using real-time polymerase chain reaction, Western blot, and immunohistochemical and immunofluorescence analyses revealed that repetitive HBOT applied after the CSI attenuates reactive astrogliosis and glial scarring, and reduces expression of GFAP (glial fibrillary acidic protein, vimentin, and ICAM-1 (intercellular adhesion molecule-1 both at gene and tissue levels. In addition, HBOT prevents expression of CD40 and its ligand CD40L on microglia, neutrophils, cortical neurons, and reactive astrocytes. Accordingly, repetitive HBOT, by prevention of glial scarring and limiting of expression of inflammatory mediators, supports formation of more permissive environment for repair and regeneration.

  10. Repetitive Hyperbaric Oxygenation Attenuates Reactive Astrogliosis and Suppresses Expression of Inflammatory Mediators in the Rat Model of Brain Injury

    Science.gov (United States)

    Lavrnja, Irena; Parabucki, Ana; Dacic, Sanja; Savic, Danijela; Pantic, Igor; Stojiljkovic, Mirjana; Pekovic, Sanja

    2015-01-01

    The exact mechanisms by which treatment with hyperbaric oxygen (HBOT) exerts its beneficial effects on recovery after brain injury are still unrevealed. Therefore, in this study we investigated the influence of repetitive HBOT on the reactive astrogliosis and expression of mediators of inflammation after cortical stab injury (CSI). CSI was performed on male Wistar rats, divided into control, sham, and lesioned groups with appropriate HBO. The HBOT protocol was as follows: 10 minutes of slow compression, 2.5 atmospheres absolute (ATA) for 60 minutes, and 10 minutes of slow decompression, once a day for 10 consecutive days. Data obtained using real-time polymerase chain reaction, Western blot, and immunohistochemical and immunofluorescence analyses revealed that repetitive HBOT applied after the CSI attenuates reactive astrogliosis and glial scarring, and reduces expression of GFAP (glial fibrillary acidic protein), vimentin, and ICAM-1 (intercellular adhesion molecule-1) both at gene and tissue levels. In addition, HBOT prevents expression of CD40 and its ligand CD40L on microglia, neutrophils, cortical neurons, and reactive astrocytes. Accordingly, repetitive HBOT, by prevention of glial scarring and limiting of expression of inflammatory mediators, supports formation of more permissive environment for repair and regeneration. PMID:25972624

  11. Intermittent high oxygen influences the formation of neural retinal tissue from human embryonic stem cells.

    Science.gov (United States)

    Gao, Lixiong; Chen, Xi; Zeng, Yuxiao; Li, Qiyou; Zou, Ting; Chen, Siyu; Wu, Qian; Fu, Caiyun; Xu, Haiwei; Yin, Zheng Qin

    2016-01-01

    The vertebrate retina is a highly multilayered nervous tissue with a large diversity of cellular components. With the development of stem cell technologies, human retinas can be generated in three-dimensional (3-D) culture in vitro. However, understanding the factors modulating key productive processes and the way that they influence development are far from clear. Oxygen, as the most essential element participating in metabolism, is a critical factor regulating organic development. In this study, using 3-D culture of human stem cells, we examined the effect of intermittent high oxygen treatment (40% O2) on the formation and cellular behavior of neural retinas (NR) in the embryonic body (EB). The volume of EB and number of proliferating cells increased significantly under 40% O2 on day 38, 50, and 62. Additionally, the ratio of PAX6+ cells within NR was significantly increased. The neural rosettes could only develop with correct apical-basal polarity under 40% O2. In addition, the generation, migration and maturation of retinal ganglion cells were enhanced under 40% O2. All of these results illustrated that 40% O2 strengthened the formation of NR in EB with characteristics similar to the in vivo state, suggesting that the hyperoxic state facilitated the retinal development in vitro. PMID:27435522

  12. Can fruits and vegetables be used as substitute phantoms for normal human brain tissues in magnetic resonance imaging?

    International Nuclear Information System (INIS)

    Various custom-made phantoms designed to optimize magnetic resonance imaging (MRI) sequences have been created and subsequently reported in Japanese Society of Radiological Technology (JSRT). However, custom-made phantoms that correctly match the T1-value and T2-values of human brain tissue (gray matter and white matter) cannot be made easily or quickly. The aim of this project was to search for alternative materials, such as fruits and vegetables, for optimizing MRI sequences. The following eight fruits and vegetables were investigated: apple, tomato, melon, apple mango (Mangifera indica), banana, avocado, peach, and eggplant. Their potential was studied for use in modeling phantoms of normal human brain tissues. MRI (T1- and T2-weighted sequences) was performed on the human brain and the fruits and vegetables using various concentrations of contrast medium (gadolinium) in the same size tubes as the custom-made phantom. The authors compared the signal intensity (SI) in human brain tissue (gray matter and white matter) with that of the fruits and the custom-made phantom. The T1 and T2 values were measured for banana tissue and compared with those for human brain tissue in the literature. Our results indicated that banana tissue is similar to human brain tissue (both gray matter and white matter). Banana tissue can thus be employed as an alternative phantom for the human brain for the purpose of MRI. (author)

  13. The response of the brain tissue to DNA double strand breaks

    International Nuclear Information System (INIS)

    Double-strand breaks (DSB) are the most deleterious form of DNA damage after ionizing radiation, the response of the brain tissue to DNA damage is related to the developmental dynamics of this system. Homology recombination is particularly important for proliferating cells, while non-homologous end joining is critical for differentiating cells. Defects in the related factors to DNA damage pathway underpin many human genopathy with neuropathology. Reviewed the signal conduction system involved in the DNA DSB response and human neuropathology genopathy related to DNA DSB factors deficiencies in the brain cells. (authors)

  14. Effects of Changes in Colored Light on Brain and Calf Muscle Blood Concentration and Oxygenation

    Directory of Open Access Journals (Sweden)

    J. Weinzirl

    2011-01-01

    Full Text Available Color light therapy is a therapeutic method in complementary medicine. In color therapy, light of two contrasting colors is often applied in a sequential order. The aim of this study was to investigate possible physiological effects, i.e., changes in the blood volume and oxygenation in the brain and calf muscle of healthy subjects who were exposed to red and blue light in sequential order. The hypothesis was that if a subject is first exposed to blue and then red light, the effect of the red light will be enhanced due to the contrastingly different characteristics of the two colors. The same was expected for blue light, if first exposing a subject to red and then to blue light. Twelve healthy volunteers (six male, six female were measured twice on two different days by near-infrared spectroscopy during exposure to colored light. Two sequences of colored light were applied in a controlled, randomized, crossover design: first blue, then red, and vice versa. For the brain and muscle, the results showed no significant differences in blood volume and oxygenation between the two sequences, and a high interindividual physiological variability. Thus, the hypothesis had to be rejected. Comparing these data to results from a previous study, where subjects were exposed to blue and red light without sequential color changes, shows that the results of the current study appear to be similar to those of red light exposure. This may indicate that the exposure to red light was preponderant and thus effects of blue light were outweighed.

  15. Near-infrared spectroscopy for monitoring of tissue oxygenation of exercising skeletal muscle in a chronic compartment syndrome model

    Science.gov (United States)

    Breit, G. A.; Gross, J. H.; Watenpaugh, D. E.; Chance, B.; Hargens, A. R.

    1997-01-01

    Variations in the levels of muscle hemoglobin and of myoglobin oxygen saturation can be detected non-invasively with near-infrared spectroscopy. This technique could be applied to the diagnosis of chronic compartment syndrome, in which invasive testing has shown increased intramuscular pressure associated with ischemia and pain during exercise. We simulated chronic compartment syndrome in ten healthy subjects (seven men and three women) by applying external compression, through a wide inflatable cuff, to increase the intramuscular pressure in the anterior compartment of the leg. The tissue oxygenation of the tibialis anterior muscle was measured with near-infrared spectroscopy during gradual inflation of the cuff to a pressure of forty millimeters of mercury (5.33 kilopascals) during fourteen minutes of cyclic isokinetic dorsiflexion and plantar flexion of the ankle. The subjects exercised with and without external compression. The data on tissue oxygenation for each subject then were normalized to a scale of 100 per cent (the baseline value, or the value at rest) to 0 per cent (the physiological minimum, or the level of oxygenation achieved by exercise to exhaustion during arterial occlusion of the lower extremity). With external compression, tissue oxygenation declined at a rate of 1.4 +/- 0.3 per cent per minute (mean and standard error) during exercise. After an initial decrease at the onset, tissue oxygenation did not decline during exercise without compression. The recovery of tissue oxygenation after exercise was twice as slow with compression (2.5 +/- 0.6 minutes) than it was without the use of compression (1.3 +/- 0.2 minutes).

  16. Hyperbaric oxygen therapy for cognitive disorders after irradiation of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Hulshof, M.C.C.M.; Sminia, P.; Gonzalez, D.G. [Amsterdam Univ. (Netherlands). Dept. of Radiation Oncology; Stark, N.M.; Smeding, H.M.M. [Amsterdam Univ. (Netherlands). Dept. of Neurology; Kleij, A. van der [Amsterdam Univ. (Netherlands). Dept. of Surgery/Hyperbaric Oxygen

    2002-04-01

    Purpose: Analysis of the feasibility and effect of hyperbaric oxygen treatment (HBO) on cognitive functioning in patients with cognitive disorders after irradiation of the brain. Patients and Method: Seven patients with cognitive impairment after brain irradiation, with an interval of at least 1.5 years after treatment, were treated with 30 sessions of HBO in a phase I-II study. A comprehensive neuropsychological test battery was performed before treatment, at 3 and 6 months thereafter. Patients were randomized into an immediate treatment group and a delayed treatment group. The delayed group had a second neurospychological test at 3 months without treatment in that period and started HBO thereafter. Results: All eligible patients completed the HBO treatment and the extensive neuropsychological testing. One out of seven patients had a meaningful improvement in neuropsychological functioning. At 3 months there was a small, but not significant benefit in neuropsychological performance for the group with HBO compared to the group without HBO treatment. Six out of seven patients eventually showed improvement after HBO in one to nine (median 2.5) of the 31 tests, although without statistical significance. Conclusion: HBO treatment was feasible and resulted in a meaningful improvement of cognitive functioning in one out of seven patients. Overall there was a small but not significant improvement. (orig.)

  17. Quantitative MALDI tandem mass spectrometric imaging of cocaine from brain tissue with a deuterated internal standard.

    Science.gov (United States)

    Pirman, David A; Reich, Richard F; Kiss, András; Heeren, Ron M A; Yost, Richard A

    2013-01-15

    Mass spectrometric imaging (MSI) is an analytical technique used to determine the distribution of individual analytes within a given sample. A wide array of analytes and samples can be investigated by MSI, including drug distribution in rats, lipid analysis from brain tissue, protein differentiation in tumors, and plant metabolite distributions. Matrix-assisted laser desorption/ionization (MALDI) is a soft ionization technique capable of desorbing and ionizing a large range of compounds, and it is the most common ionization source used in MSI. MALDI mass spectrometry (MS) is generally considered to be a qualitative analytical technique because of significant ion-signal variability. Consequently, MSI is also thought to be a qualitative technique because of the quantitative limitations of MALDI coupled with the homogeneity of tissue sections inherent in an MSI experiment. Thus, conclusions based on MS images are often limited by the inability to correlate ion signal increases with actual concentration increases. Here, we report a quantitative MSI method for the analysis of cocaine (COC) from brain tissue using a deuterated internal standard (COC-d(3)) combined with wide-isolation MS/MS for analysis of the tissue extracts with scan-by-scan COC-to-COC-d(3) normalization. This resulted in significant improvements in signal reproducibility and calibration curve linearity. Quantitative results from the MSI experiments were compared with quantitative results from liquid chromatography (LC)-MS/MS results from brain tissue extracts. Two different quantitative MSI techniques (standard addition and external calibration) produced quantitative results comparable to LC-MS/MS data. Tissue extracts were also analyzed by MALDI wide-isolation MS/MS, and quantitative results were nearly identical to those from LC-MS/MS. These results clearly demonstrate the necessity for an internal standard for quantitative MSI experiments. PMID:23214490

  18. A non-aggressive, highly efficient, enzymatic method for dissociation of human brain-tumors and brain-tissues to viable single-cells

    OpenAIRE

    Volovitz, Ilan; Shapira, Netanel; Ezer, Haim; Gafni, Aviv; Lustgarten, Merav; Alter, Tal; Ben-Horin, Idan; Barzilai, Ori; Shahar, Tal; Kanner, Andrew; Fried, Itzhak; Veshchev, Igor; Grossman, Rachel; Ram, Zvi

    2016-01-01

    Background Conducting research on the molecular biology, immunology, and physiology of brain tumors (BTs) and primary brain tissues requires the use of viably dissociated single cells. Inadequate methods for tissue dissociation generate considerable loss in the quantity of single cells produced and in the produced cells’ viability. Improper dissociation may also demote the quality of data attained in functional and molecular assays due to the presence of large quantities cellular debris conta...

  19. Concentrations of Nitric Oxide in Rat Brain Tissues after Diffuse Brain Injury and Neuroprotection by the Selective Inducible Nitric Oxide Synthase Inhibitor Aminoguanidine

    Institute of Scientific and Technical Information of China (English)

    Yi-bao Wang; Shao-wu Ou; Guang-yu Li; Yun-hui Liu

    2005-01-01

    @@ To investigate the effects of nitric oxide (NO) and the selective inducible nitric oxide synthase (iNOS) inhibitor aminoguanidine (AG) on trauma, we explored the concentrations of nitric oxide in rat brain tissues at different time stamps after diffuse brain injury (DBI) with or without AG treatment.

  20. Cranial irradiation induces bone marrow-derived microglia in adult mouse brain tissue.

    Science.gov (United States)

    Okonogi, Noriyuki; Nakamura, Kazuhiro; Suzuki, Yoshiyuki; Suto, Nana; Suzue, Kazutomo; Kaminuma, Takuya; Nakano, Takashi; Hirai, Hirokazu

    2014-07-01

    Postnatal hematopoietic progenitor cells do not contribute to microglial homeostasis in adult mice under normal conditions. However, previous studies using whole-body irradiation and bone marrow (BM) transplantation models have shown that adult BM cells migrate into the brain tissue and differentiate into microglia (BM-derived microglia; BMDM). Here, we investigated whether cranial irradiation alone was sufficient to induce the generation of BMDM in the adult mouse brain. Transgenic mice that express green fluorescent protein (GFP) under the control of a murine stem cell virus (MSCV) promoter (MSCV-GFP mice) were used. MSCV-GFP mice express GFP in BM cells but not in the resident microglia in the brain. Therefore, these mice allowed us to detect BM-derived cells in the brain without BM reconstitution. MSCV-GFP mice, aged 8-12 weeks, received 13.0 Gy irradiation only to the cranium, and BM-derived cells in the brain were quantified at 3 and 8 weeks after irradiation. No BM-derived cells were detected in control non-irradiated MSCV-GFP mouse brains, but numerous GFP-labeled BM-derived cells were present in the brain stem, basal ganglia and cerebral cortex of the irradiated MSCV-GFP mice. These BM-derived cells were positive for Iba1, a marker for microglia, indicating that GFP-positive BM-derived cells were microglial in nature. The population of BMDM was significantly greater at 8 weeks post-irradiation than at 3 weeks post-irradiation in all brain regions examined. Our results clearly show that cranial irradiation alone is sufficient to induce the generation of BMDM in the adult mouse.

  1. Microinjection of membrane-impermeable molecules into single neural stem cells in brain tissue.

    Science.gov (United States)

    Wong, Fong Kuan; Haffner, Christiane; Huttner, Wieland B; Taverna, Elena

    2014-05-01

    This microinjection protocol allows the manipulation and tracking of neural stem and progenitor cells in tissue at single-cell resolution. We demonstrate how to apply microinjection to organotypic brain slices obtained from mice and ferrets; however, our technique is not limited to mouse and ferret embryos, but provides a means of introducing a wide variety of membrane-impermeable molecules (e.g., nucleic acids, proteins, hydrophilic compounds) into neural stem and progenitor cells of any developing mammalian brain. Microinjection experiments are conducted by using a phase-contrast microscope equipped with epifluorescence, a transjector and a micromanipulator. The procedure normally takes ∼2 h for an experienced researcher, and the entire protocol, including tissue processing, can be performed within 1 week. Thus, microinjection is a unique and versatile method for changing and tracking the fate of a cell in organotypic slice culture.

  2. Buyanghuanwu decoction promotes angiogenesis after cerebral ischemia/reperfusion injury: mechanisms of brain tissue repair.

    Science.gov (United States)

    Zhang, Zhen-Qiang; Song, Jun-Ying; Jia, Ya-Quan; Zhang, Yun-Ke

    2016-03-01

    Buyanghuanwu decoction has been shown to protect against cerebral ischemia/reperfusion injury, but the underlying mechanisms remain unclear. In this study, rats were intragastrically given Buyanghuanwu decoction, 15 mL/kg, for 3 days. A rat model of cerebral ischemia/reperfusion injury was established by middle cerebral artery occlusion. In rats administered Buyanghuanwu decoction, infarct volume was reduced, serum vascular endothelial growth factor and integrin αvβ3 levels were increased, and brain tissue vascular endothelial growth factor and CD34 expression levels were increased compared with untreated animals. These effects of Buyanghuanwu decoction were partially suppressed by an angiogenesis inhibitor (administered through the lateral ventricle for 7 consecutive days). These data suggest that Buyanghuanwu decoction promotes angiogenesis, improves cerebral circulation, and enhances brain tissue repair after cerebral ischemia/reperfusion injury. PMID:27127482

  3. Buyanghuanwu decoction promotes angiogenesis after cerebral ischemia/reperfusion injury:mechanisms of brain tissue repair

    Institute of Scientific and Technical Information of China (English)

    Zhen-qiang Zhang; Jun-ying Song; Ya-quan Jia; Yun-ke Zhang

    2016-01-01

    Buyanghuanwu decoction has been shown to protect against cerebral ischemia/reperfusion injury, but the underlying mechanisms remain unclear. In this study, rats were intragastrically givenBuyanghuanwu decoction, 15 mL/kg, for 3 days. A rat model of cerebral ischemia/reper-fusion injury was established by middle cerebral artery occlusion. In rats administeredBuyanghuanwu decoction, infarct volume was reduced, serum vascular endothelial growth factor and integrinαvβ3 levels were increased, and brain tissue vascular endothelial growth factor and CD34 expression levels were increased compared with untreated animals. These effects ofBuyanghuanwu decoction were partially suppressed by an angiogenesis inhibitor (administered through the lateral ventricle for 7 consecutive days). These data suggest thatBuyanghuanwu de-coction promotes angiogenesis, improves cerebral circulation, and enhances brain tissue repair after cerebral ischemia/reperfusion injury.

  4. Buyanghuanwu decoction promotes angiogenesis after cerebral ischemia/reperfusion injury: mechanisms of brain tissue repair

    Directory of Open Access Journals (Sweden)

    Zhen-qiang Zhang

    2016-01-01

    Full Text Available Buyanghuanwu decoction has been shown to protect against cerebral ischemia/reperfusion injury, but the underlying mechanisms remain unclear. In this study, rats were intragastrically given Buyanghuanwu decoction, 15 mL/kg, for 3 days. A rat model of cerebral ischemia/reperfusion injury was established by middle cerebral artery occlusion. In rats administered Buyanghuanwu decoction, infarct volume was reduced, serum vascular endothelial growth factor and integrin αvβ3 levels were increased, and brain tissue vascular endothelial growth factor and CD34 expression levels were increased compared with untreated animals. These effects of Buyanghuanwu decoction were partially suppressed by an angiogenesis inhibitor (administered through the lateral ventricle for 7 consecutive days. These data suggest that Buyanghuanwu decoction promotes angiogenesis, improves cerebral circulation, and enhances brain tissue repair after cerebral ischemia/reperfusion injury.

  5. Identifying signature Zernike modes for efficient light delivery through brain tissue

    CERN Document Server

    Sane, Sharmila; Lee, Woei Ming; Stricker, Christian; Bachor, Hans; Daria, Vincent

    2015-01-01

    Recent progress in neuroscience to image and investigate brain function has been made possible by impressive developments in optogenetic and opto-molecular tools. Such research requires advances in optical techniques for the delivery of light through brain tissue with high spatial resolution. The tissue causes distortions of the wavefront of the incoming light which broadens the focus, thereby reducing the intensity and resolution especially in techniques requiring focal illumination. Adaptive wavefront correction has been demonstrated to compensate for these distortions. However, in many situations iterative derivation of the corrective wavefront introduces time constraints that limit its usefulness when used to probe living cells. Here we demonstrate a direct and fast technique by working with a small set of Zernike modes and demonstrate that corrections derived a priori can lead to significant improvement of the focus. We verify this idea by the electrical response of whole-cell patched neurons following t...

  6. Characterisation of new monoclonal antibodies reacting with prions from both human and animal brain tissues

    DEFF Research Database (Denmark)

    Hvass, Henriette Cordes; Bergström, Ann-Louise; Ohm, Jakob;

    2008-01-01

    Post-mortem diagnosis of transmissible spongiform encephalopaties (prion diseases) is primarily based on the detection of a protease resistant, misfolded disease associated isoform (PrPSc) of the prion protein (PrPc) on neuronal cells. These methods depend on antibodies directed aganinst Pr......-type mice and used for western blotting and immunohistochemistry to detect several types of human prion-disease associated PrPSc, including sporadic Creutzfeldt-Jakob Disease (CJD) (subtypes MM1 and V"), familial CJD and Gerstmann-Sträussler-Scheinker (GSS) disease PrPSc as well as PrPSc of bovine...... spongiform encephalopathy (bovine brain), scrapie (ovine brain) and experimental scrapie in hamster and in mice. The antibodies were also used for PET-blotting in which PrPSc blotted from brain tissue sections onto a nitrocellulose membrane is visualized with antibodies after protease and denaturant...

  7. Evaluation of cardiac functions of cirrhotic children using serum brain natriuretic peptide and tissue Doppler imaging

    OpenAIRE

    Aya M Fattouh; El-Shabrawi, Mortada H; Enas H Mahmoud; Wafaa O Ahmed

    2016-01-01

    Background: Cirrhotic cardiomyopathy (CCM) is described as the presence of cardiac dysfunction in cirrhotic patients. In children with chronic liver disease, CCM has been very rarely investigated. The Aim of the Study: Is to evaluate the cardiac function of cirrhotic children to identify those with CCM. Patients and Methods: Fifty-two cirrhotic patients and 53 age and sex matched controls were assessed using serum brain-type natriuretic peptide (BNP), conventional echocardiography, and tissue...

  8. Evidence for Fungal Infection in Cerebrospinal Fluid and Brain Tissue from Patients with Amyotrophic Lateral Sclerosis

    OpenAIRE

    Alonso, Ruth; Pisa, Diana; Marina, Ana Isabel; Morato, Esperanza; Rábano, Alberto; Rodal, Izaskun; Carrasco, Luis

    2015-01-01

    Among neurogenerative diseases, amyotrophic lateral sclerosis (ALS) is a fatal illness characterized by a progressive motor neuron dysfunction in the motor cortex, brainstem and spinal cord. ALS is the most common form of motor neuron disease; yet, to date, the exact etiology of ALS remains unknown. In the present work, we have explored the possibility of fungal infection in cerebrospinal fluid (CSF) and in brain tissue from ALS patients. Fungal antigens, as well as DNA from several fungi, we...

  9. Nitric oxide synthase and neuronal NADPH diaphorase are identical in brain and peripheral tissues.

    OpenAIRE

    Dawson, T. M.; Bredt, D S; M Fotuhi; Hwang, P M; Snyder, S. H.

    1991-01-01

    NADPH diaphorase staining neurons, uniquely resistant to toxic insults and neurodegenerative disorders, have been colocalized with neurons in the brain and peripheral tissue containing nitric oxide synthase (EC 1.14.23.-), which generates nitric oxide (NO), a recently identified neuronal messenger molecule. In the corpus striatum and cerebral cortex, NO synthase immunoreactivity and NADPH diaphorase staining are colocalized in medium to large aspiny neurons. These same neurons colocalize with...

  10. Cardiovascular haemodynamics in pre-eclampsia using brain naturetic peptide and tissue Doppler studies

    OpenAIRE

    Naidoo, DP; Fayers, S; Moodley, J

    2013-01-01

    Aim To determine early haemodynamic changes in pre-eclampsia (PE) using tissue Doppler echocardiography and brain natriuretic peptide (BNP), and to relate these changes to obstetric outcomes. Methods Consenting primigravidae patients in the third trimester of pregnancy were included in the study, which was carried out in a large regional hospital in Durban, South Africa; 115 primigravidae (52 pre-eclamptics and 63 normotensive pregnant patients) attending the maternity unit including the ante...

  11. Maternal Prenatal Iron Status and Tissue Organization in the Neonatal Brain

    OpenAIRE

    Monk, Catherine; Georgieff, Michael K.; Xu, Dongrong; Hao, Xuejun; Bansal, Ravi; Gustafsson, Hanna; Spicer, Julie; Peterson, Bradley S.

    2015-01-01

    Background Children prenatally exposed to inadequate iron have poorer motor and neurocognitive development. No prior study to our knowledge has assessed the influence of maternal prenatal iron intake on newborn brain tissue organization in fullterm infants. Methods 3rd trimester daily iron intake was obtained using the Automated SelfAdministered 24hour Dietary Recall with n=40 healthy pregnant adolescents (14–19 years old). Cord blood ferritin was collected in a subsample (n=16). Newborn (m=3...

  12. Identification of pro-angiogenic markers in blood vessels from stroked-affected brain tissue using laser-capture microdissection

    Directory of Open Access Journals (Sweden)

    Baldellou Maribel

    2009-03-01

    Full Text Available Abstract Background Angiogenesis correlates with patient survival following acute ischaemic stroke, and survival of neurons is greatest in tissue undergoing angiogenesis. Angiogenesis is critical for the development of new microvessels and leads to re-formation of collateral circulation, reperfusion, enhanced neuronal survival and improved recovery. Results Here, we have isolated active (CD105/Flt-1 positive and inactive (CD105/Flt-1 minus (n=5 micro-vessel rich-regions from stroke-affected and contralateral tissue of patients using laser-capture micro-dissection. Areas were compared for pro- and anti-angiogenic gene expression using targeted TaqMan microfluidity cards containing 46 genes and real-time PCR. Further analysis of key gene de-regulation was performed by immunohistochemistry to define localization and expression patterns of identified markers and de novo synthesis by human brain microvessel endothelial cells (HBMEC was examined following oxygen-glucose deprivation (OGD. Our data revealed that seven pro-angiogenic genes were notably up-regulated in CD105 positive microvessel rich regions. These were, beta-catenin, neural cell adhesion molecule (NRCAM, matrix metalloproteinase-2 (MMP-2, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1, hepatocyte growth factor-alpha (HGF-alpha, monocyte chemottractant protein-1 (MCP-1 and and Tie-2 as well as c-kit. Immunohistochemistry demonstrated strong staining of MMP-2, HGF-alpha, MCP-1 and Tie-2 in stroke-associated regions of active remodeling in association with CD105 positive staining. In vitro, OGD stimulated production of Tie-2, MCP-1 and MMP-2 in HBMEC, demonstrated a de novo response to hypoxia. Conclusion In this work we have identified concurrent activation of key angiogenic molecules associated with endothelial cell migration, differentiation and tube-formation, vessel stabilization and stem cell homing mechanisms in areas of revascularization. Therapeutic stimulation of these

  13. Multigrid Nonlocal Gaussian Mixture Model for Segmentation of Brain Tissues in Magnetic Resonance Images

    Directory of Open Access Journals (Sweden)

    Yunjie Chen

    2016-01-01

    Full Text Available We propose a novel segmentation method based on regional and nonlocal information to overcome the impact of image intensity inhomogeneities and noise in human brain magnetic resonance images. With the consideration of the spatial distribution of different tissues in brain images, our method does not need preestimation or precorrection procedures for intensity inhomogeneities and noise. A nonlocal information based Gaussian mixture model (NGMM is proposed to reduce the effect of noise. To reduce the effect of intensity inhomogeneity, the multigrid nonlocal Gaussian mixture model (MNGMM is proposed to segment brain MR images in each nonoverlapping multigrid generated by using a new multigrid generation method. Therefore the proposed model can simultaneously overcome the impact of noise and intensity inhomogeneity and automatically classify 2D and 3D MR data into tissues of white matter, gray matter, and cerebral spinal fluid. To maintain the statistical reliability and spatial continuity of the segmentation, a fusion strategy is adopted to integrate the clustering results from different grid. The experiments on synthetic and clinical brain MR images demonstrate the superior performance of the proposed model comparing with several state-of-the-art algorithms.

  14. Super resolution imaging of genetically labelled synapses in Drosophila brain tissue

    Directory of Open Access Journals (Sweden)

    Isabelle Ayumi Spühler

    2016-05-01

    Full Text Available Understanding synaptic connectivity and plasticity within brain circuits and their relationship to learning and behavior is a fundamental quest in neuroscience. Visualizing the fine details of synapses using optical microscopy remains however a major technical challenge. Super resolution microscopy opens the possibility to reveal molecular features of synapses beyond the diffraction limit. With direct stochastic optical reconstruction microscopy, dSTORM, we image synaptic proteins in the brain tissue of the fruit fly, Drosophila melanogaster. Super resolution imaging of brain tissue harbors difficulties due to light scattering and the density of signals. In order to reduce out of focus signal, we take advantage of the genetic tools available in the Drosophila and have fluorescently tagged synaptic proteins expressed in only a small number of neurons. These neurons form synapses within the calyx of the mushroom body, a distinct brain region involved in associative memory formation. Our results show that super resolution microscopy, in combination with genetically labelled synaptic proteins, is a powerful tool to investigate synapses in a quantitative fashion providing an entry point for studies on synaptic plasticity during learning and memory formation

  15. Mechanical Characterization of Brain Tissue in Compression at Dynamic Strain Rates

    CERN Document Server

    Rashid, Badar; Gilchrist, Michael; 10.1016/j.jmbbm.2012.01.022

    2013-01-01

    Traumatic brain injury (TBI) occurs when local mechanical load exceeds certain tolerance levels for brain tissue. Extensive research has been done previously for brain matter experiencing compression at quasistatic loading; however, limited data is available to model TBI under dynamic impact conditions. In this research, an experimental setup was developed to perform unconfined compression tests and stress relaxation tests at strain rates < 90/s. The brain tissue showed a stiffer response with increasing strain rates, showing that hyperelastic models are not adequate. Specifically, the compressive nominal stress at 30% strain was 8.83 +/- 1.94, 12.8 +/- 3.10 and 16.0 +/- 1.41 kPa (mean +/- SD) at strain rates of 30, 60 and 90/s, respectively. Relaxation tests were also conducted at 10%-50% strain with the average rise time of 10 ms, which can be used to derive time dependent parameters. Numerical simulations were performed using one-term Ogden model with initial shear modulus mu_0 = 6.06 +/- 1.44, 9.44 +/-...

  16. Imaging Nicotine in Rat Brain Tissue by Use of Nanospray Desorption Electrospray Ionization Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lanekoff, Ingela T.; Thomas, Mathew; Carson, James P.; Smith, Jordan N.; Timchalk, Charles; Laskin, Julia

    2013-01-15

    Imaging mass spectrometry offers simultaneous detection of drugs, drug metabolites and endogenous substances in a single experiment. This is important when evaluating effects of a drug on a complex organ system such as the brain, where there is a need to understand how regional drug distribution impacts function. Nicotine is an addictive drug and its action in the brain is of high interest. Here we use nanospray desorption electrospray ionization, nano-DESI, imaging to discover the localization of nicotine in rat brain tissue after in vivo administration of nicotine. Nano-DESI is a new ambient technique that enables spatially-resolved analysis of tissue samples without special sample pretreatment. We demonstrate high sensitivity of nano-DESI imaging that enables detection of only 0.7 fmole nicotine per pixel in the complex brain matrix. Furthermore, by adding deuterated nicotine to the solvent, we examined how matrix effects, ion suppression, and normalization affect the observed nicotine distribution. Finally, we provide preliminary results suggesting that nicotine localizes to the hippocampal substructure called dentate gyrus.

  17. Preliminary observation of genes specifically expressed in brain tissues during stroke-like episodes in rats

    Institute of Scientific and Technical Information of China (English)

    WANG Xian-mei; ZHAO Bin; ZHU Shan-jun; ZHU Zhi-ming; ZHANG Qian; HUI Ru-tai

    2001-01-01

    Objective: To observe the difference of gene expressions of brain tissues during apoplectic episodes and those of normal brain in Wistar rats in order to study the pathological mechanism of apoplexy. Methods: A rat model of hypertension was established with the administration of cold stimulus and high salt intake as the environmental risk factors.Apoplexy occurred in the rats because of hypertension. Suppression subtractive hybridization(SSH) was used to identify and analyze the differential genes specifically expressed in cerebral tissues of stoke group and control rats. Results: A total of 226 genes out of the 228 were usable and analyzed. The average length of the 226 genes was (286.6±120.3) bp with a range from 50 bp to 619 bp. And 126 clones out of the 226 showed a sequence with significant identity to the known genes; 78 clones demonstrated homogenous sequences to the existing ESTs ofdbEST, but no one of the 78 showed sequence with identity to that of known genes; and remaining 22 were novel transrcipts exhibiting no similarity to any known sequences. All the clones which were highly homogenous to the known genes were categorized on the basis of their function. It was found that 26.5% of the mitochodrial genes in brain tissues underwent changes after apoplexy and the changes showed a twofold relationship of cause and effect. Conclusion: Environmental factors are able to induce changes of gene expression, which may increase the sensitivity to apoplectic stroke.

  18. Optical vortex beam transmission with different OAM in scattering beads and brain tissue media

    Science.gov (United States)

    Wang, W. B.; Shi, Lingyan; Lindwasser, Lukas; Marque, Paulo; Lavery, M. P. J.; Alfano, R. R.

    2016-03-01

    Light transmission of Laguerre Gaussian (LG) vortex beams with different orbital angular momentum (OAM) values (L) in scattering beads and mouse brain tissue media were experimentally investigated for the first time in comparison with Gaussian (G) beams. The LG beams with different OAM were generated using a spatial light modulator (SLM) in reflection mode. The scattering beads media consist of various sizes and concentrations of latex beads in water solutions. The transmissions of LG and G beams through scattering beads and brain tissue media were measured with different ratios of sample thicknesses (z) to scattering mean free path (ls) of the turbid media, z/ls. The results indicate that within the ballistic region where z/ls is small, the LG and G beams show no significant difference, while in the diffusive region where z/ls is higher, the vortex beams show higher transmission than G beams. In the diffusive region, the LG beams with higher L values show higher transmission than the beams with lower L values due to the eigen channels in the media. The transition points from the ballistic to diffusive regions for different scattering beads and brain tissue media were studied.

  19. Identification of some volatile endogenous constituents in rat brain tissue and the effects of lithium carbonate and chloral hydrate.

    Science.gov (United States)

    Politzer, I R; McDonald, L K; Laseter, J L

    1976-11-01

    Nine endogenous volatile compounds were found in rat brain tissue, and were identified by mass spectrometry as chloroform, a 5-C-aldehyde, dimethyl disulphide, 2,5-dimethyl tetrahydrofuran, a 8-C-alkane, xylene, 2-heptanone, heptaldehyde and 2-n-pentylfuran. Using gas chromatographic and gas chromatographic mass spectrometric techniques, it was established that lithium carbonate did not induce the production of detectable amounts of any new volatile compounds in brain tissue. However, after administration of chloral hydrate, trichloroethanol, a compound not normally present in rat brain tissue, was found to be present. PMID:996360

  20. Imaging changes in blood volume and oxygenation in the newborn infant brain using three-dimensional optical tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hebden, Jeremy C [Department of Medical Physics and Bioengineering, University College London, 11-20 Capper Street, London WC1E 6JA (United Kingdom); Gibson, Adam [Department of Medical Physics and Bioengineering, University College London, 11-20 Capper Street, London WC1E 6JA (United Kingdom); Austin, Topun [Department of Paediatrics and Child Health, University College London, 5 University Street, London WC1E 6JJ (United Kingdom); Yusof, Rozarina Md [Department of Medical Physics and Bioengineering, University College London, 11-20 Capper Street, London WC1E 6JA (United Kingdom); Everdell, Nick [Department of Medical Physics and Bioengineering, University College London, 11-20 Capper Street, London WC1E 6JA (United Kingdom); Delpy, David T [Department of Medical Physics and Bioengineering, University College London, 11-20 Capper Street, London WC1E 6JA (United Kingdom); Arridge, Simon R [Department of Computer Science, University College London, Gower Street, London WC1E 6BT (United Kingdom); Meek, Judith H [Department of Paediatrics and Child Health, University College London, 5 University Street, London WC1E 6JJ (United Kingdom); Wyatt, John S [Department of Paediatrics and Child Health, University College London, 5 University Street, London WC1E 6JJ (United Kingdom)

    2004-04-07

    Induced haemodynamic and blood oxygenation changes occurring within the brain of a ventilated newborn infant have been imaged in three dimensions using optical tomography. Noninvasive measurements of the flight times of transmitted light were acquired during illumination of the brain by laser pulses at wavelengths of 780 nm and 815 nm. The oxygen and carbon dioxide partial pressures were adjusted through alterations to the ventilator settings, resulting in changes to the cerebral blood volume and oxygenation. Three-dimensional images were generated using the physiologically associated differences in the measured data, obviating the need for data calibration using a separate reference measurement. The results exhibit large changes in absorption coefficient at both wavelengths. Images corresponding to differences in concentrations of oxy- and deoxyhaemoglobin are in qualitative agreement with known physiological data.

  1. Imaging changes in blood volume and oxygenation in the newborn infant brain using three-dimensional optical tomography

    International Nuclear Information System (INIS)

    Induced haemodynamic and blood oxygenation changes occurring within the brain of a ventilated newborn infant have been imaged in three dimensions using optical tomography. Noninvasive measurements of the flight times of transmitted light were acquired during illumination of the brain by laser pulses at wavelengths of 780 nm and 815 nm. The oxygen and carbon dioxide partial pressures were adjusted through alterations to the ventilator settings, resulting in changes to the cerebral blood volume and oxygenation. Three-dimensional images were generated using the physiologically associated differences in the measured data, obviating the need for data calibration using a separate reference measurement. The results exhibit large changes in absorption coefficient at both wavelengths. Images corresponding to differences in concentrations of oxy- and deoxyhaemoglobin are in qualitative agreement with known physiological data

  2. THE STATE OF THE WATER IN BRAIN TISSUE IN PRESENCE OF TS-100 NANOPARTICLES

    Directory of Open Access Journals (Sweden)

    T. V.

    2015-12-01

    Full Text Available By the method of low-temperature 1Н NMR spectroscopy the structure of the hydrate layers of water associated with brain cells, the changes of these parameters during necrotic lesions (stroke and in the presence of trifluoroacetic acid, which allows differentiating intracellular water clusters according to their ability to dissolve the acid, were studied. Also the impact of silica TS-100 nanoparticles on the state of water in brain tissue, namely on the water binding parameters in the air and in the presence of a weakly polar solvent was considered. The distributions by the radii and change of Gibbs free energy for clusters of strongly bound interfacial water were obtained. It was shown that the hydration properties of the native brain tissue differ from the hydration properties of necrotic damaged tissue by the structure of weakly bound water clusters. In intact tissue all the water is associated and is a part of clusters and domains, most of which have a radii R = 2 and 20 nm. The media with chloroform stabilizes water polyassociates with the radius up to R = 100 nm and trifluoroacetic acid stabilizes water polyassociates with radii R = 7–20 nm. It was found that the partial dehydration of the investigated tissue samples is accompanied by decreasing of weakly bound water amount and some increasing of strongly bound water that indicates a change of molecular interactions between the components of cells-nanoparticles composite system. The ischemic necrosis area presence leads to a decrease of water binding due to the average size water polyassociates increasing. This effect is observed both in air and in a weakly polar organic solvent medium (deuterochloroform.

  3. Feasibility of long-term cerebral and peripheral regional tissue oxygen saturation measurements

    International Nuclear Information System (INIS)

    The aim of this study was to analyse the feasibility of long-term measurements of cerebral (crSO2) and peripheral (prSO2) regional tissue oxygen saturation on the first day of life by determining the amount of artefacts and their influence on rSO2. Near infrared spectroscopy (NIRS) measurements were performed fronto-parietal left (crSO2) and on the right forearm (prSO2). Arterial oxygen saturation (SpO2) was measured by pulse oximetry on the right wrist. Three criteria (C) were defined to identify artefacts (C1: missing values, C2: rSO2 jumping >15%, C3: rSO2 ≥ SpO2). The number of artefacts as a percentage of measurement time and mean rSO2 was calculated after the introduction of each criterion. Measurements were performed in 40 neonates. The number of artefacts in crSO2 measurements was similar after introduction of C1 (7.37 ± 4.64%) and after introduction of all criteria (8.89 ± 4.59%). The number of artefacts in prSO2 measurements after introduction of C1 was 10.83 ± 4.21%, and after introduction of all criteria significantly higher with 17.78 ± 4.27%. After introduction of C1, further criteria did not significantly change rSO2: crSO2 (78.6 ± 1.3% versus 78.5 ± 1.2%) and prSO2 (83.7 ± 0.9% versus 83.5 ± 0.9%). In conclusion, long-term NIRS measurements of crSO2 and prSO2 are feasible, since most artefacts are due to missing values and therefore easy to recognize. (paper)

  4. Changes in Rat Brain Tissue Microstructure and Stiffness during the Development of Experimental Obstructive Hydrocephalus.

    Science.gov (United States)

    Jugé, Lauriane; Pong, Alice C; Bongers, Andre; Sinkus, Ralph; Bilston, Lynne E; Cheng, Shaokoon

    2016-01-01

    Understanding neural injury in hydrocephalus and how the brain changes during the course of the disease in-vivo remain unclear. This study describes brain deformation, microstructural and mechanical properties changes during obstructive hydrocephalus development in a rat model using multimodal magnetic resonance (MR) imaging. Hydrocephalus was induced in eight Sprague-Dawley rats (4 weeks old) by injecting a kaolin suspension into the cisterna magna. Six sham-injected rats were used as controls. MR imaging (9.4T, Bruker) was performed 1 day before, and at 3, 7 and 16 days post injection. T2-weighted MR images were collected to quantify brain deformation. MR elastography was used to measure brain stiffness, and diffusion tensor imaging (DTI) was conducted to observe brain tissue microstructure. Results showed that the enlargement of the ventricular system was associated with a decrease in the cortical gray matter thickness and caudate-putamen cross-sectional area (P hydrocephalus development, increased space between the white matter tracts was observed in the CC+PVWM (P hydrocephalus development.

  5. Advanced biomaterial strategies to transplant preformed micro-tissue engineered neural networks into the brain

    Science.gov (United States)

    Harris, J. P.; Struzyna, L. A.; Murphy, P. L.; Adewole, D. O.; Kuo, E.; Cullen, D. K.

    2016-02-01

    Objective. Connectome disruption is a hallmark of many neurological diseases and trauma with no current strategies to restore lost long-distance axonal pathways in the brain. We are creating transplantable micro-tissue engineered neural networks (micro-TENNs), which are preformed constructs consisting of embedded neurons and long axonal tracts to integrate with the nervous system to physically reconstitute lost axonal pathways. Approach. We advanced micro-tissue engineering techniques to generate micro-TENNs consisting of discrete populations of mature primary cerebral cortical neurons spanned by long axonal fascicles encased in miniature hydrogel micro-columns. Further, we improved the biomaterial encasement scheme by adding a thin layer of low viscosity carboxymethylcellulose (CMC) to enable needle-less insertion and rapid softening for mechanical similarity with brain tissue. Main results. The engineered architecture of cortical micro-TENNs facilitated robust neuronal viability and axonal cytoarchitecture to at least 22 days in vitro. Micro-TENNs displayed discrete neuronal populations spanned by long axonal fasciculation throughout the core, thus mimicking the general systems-level anatomy of gray matter—white matter in the brain. Additionally, micro-columns with thin CMC-coating upon mild dehydration were able to withstand a force of 893 ± 457 mN before buckling, whereas a solid agarose cylinder of similar dimensions was predicted to withstand less than 150 μN of force. This thin CMC coating increased the stiffness by three orders of magnitude, enabling needle-less insertion into brain while significantly reducing the footprint of previous needle-based delivery methods to minimize insertion trauma. Significance. Our novel micro-TENNs are the first strategy designed for minimally invasive implantation to facilitate nervous system repair by simultaneously providing neuronal replacement and physical reconstruction of long-distance axon pathways in the brain

  6. NIRS-Derived Tissue Oxygen Saturation and Hydrogen Ion Concentration Following Bed Rest

    Science.gov (United States)

    Lee, S. M. C.; Everett, M. E.; Crowell, J. B.; Westby, C. M.; Soller, B. R.

    2010-01-01

    Long-term bed rest (BR), a model of spaceflight, results in a decrease in aerobic capacity and altered submaximal exercise responses. The strongest BR-induced effects on exercise appear to be centrally-mediated, but longer BR durations may result in peripheral adaptations (e.g., decreased mitochondrial and capillary density) which are likely to influence exercise responses. PURPOSE: To measure tissue oxygen saturation (SO2) and hydrogen ion concentration ([H+]) in the vastus lateralis (VL) using near infrared spectroscopy (NIRS) during cycle ergometry before and after . 30 d of BR. METHODS: Eight subjects performed a graded exercise test on a cycle ergometer to volitional fatigue 7 d before (pre-BR) and at the end or 1 day after BR (post-BR). NIRS spectra were collected from a sensor adhered to the skin overlying the VL. Oxygen consumption (VO2) was measured by open circuit spirometry. Blood volume (BV) was measured before and after BR using the carbon monoxide rebreathing technique. Changes in pre- and post-BR SO2 and [H+] data were compared using mixed model analyses. BV and peak exercise data were compared using paired t-tests. RESULTS: BV (pre-BR: 4.3+/-0.3, post-BR: 3.7+/-0.2 L, mean+/-SE, p=.01) and peak VO2 (pre-BR: 1.98+/-0.24, post-BR: 1.48 +/-0.21 L/min, p<.01) were reduced after BR. As expected, SO2 decreased with exercise before and after BR. However, SO2 was lower post compared with pre-BR throughout exercise, including at peak exercise (pre-BR: 50+/-3, post-BR: 43+/-4%, p=.01). After BR, [H+] was higher at the start of exercise and did not increase at the same rate as pre-BR. Peak [H+] was not different from pre to post-BR (pre-BR: 36+/-2; post-BR: 38+/-2 nmol/L). CONCLUSIONS: Lower SO2 during exercise suggests that oxygen extraction in the VL is higher after BR, perhaps due to lower circulating blood volume. The higher [H+] after BR suggests a greater reliance upon glycolysis during submaximal exercise, although [H+] at peak exercise was unchanged

  7. Intracellular expression of reactive oxygen species-generating NADPH oxidase NOX4 in normal and cancer thyroid tissues

    NARCIS (Netherlands)

    U. Weyemi; B. Caillou; M. Talbot; R. Ameziane-El-Hassani; L. Lacroix; O. Lagent-Chevallier; A. Al Ghuzlan; D. Roos; J.M. Bidart; A. Virion; M. Schlumberger; C. Dupuy

    2010-01-01

    NADPH oxidase 4 (NOX4) belongs to the NOX family that generates reactive oxygen species (ROS). Function and tissue distribution of NOX4 have not yet been entirely clarified. To date, in the thyroid gland, only DUOX1/2 NOX systems have been described. NOX4 mRNA expression, as shown by real-time PCR,

  8. X-ray diffraction from intact tau aggregates in human brain tissue

    Science.gov (United States)

    Landahl, Eric C.; Antipova, Olga; Bongaarts, Angela; Barrea, Raul; Berry, Robert; Binder, Lester I.; Irving, Thomas; Orgel, Joseph; Vana, Laurel; Rice, Sarah E.

    2011-09-01

    We describe an instrument to record X-ray diffraction patterns from diseased regions of human brain tissue by combining an in-line visible light fluorescence microscope with an X-ray diffraction microprobe. We use thiazine red fluorescence to specifically label and detect the filamentous tau protein pathology associated with Pick's disease, as several laboratories have done previously. We demonstrate that thiazine red-enhanced regions within the tissue show periodic structure in X-ray diffraction, which is not observed in healthy tissue. One observed periodicity (4.2 Å) is characteristic of cross-beta sheet structure, consistent with previous results from powder diffraction studies performed on purified, dried tau protein.

  9. X-ray diffraction from intact tau aggregates in human brain tissue

    Energy Technology Data Exchange (ETDEWEB)

    Landahl, Eric C. [DePaul University, Department of Physics, 2219 N. Kenmore Ave., IL 60614, Chicago (United States); Antipova, Olga [Illinois Institute of Technology, Department of Biological Chemical and Physical Sciences, 3101 South Dearborn St., IL 60616, Chicago (United States); Bongaarts, Angela [Northwestern University, Department of Cell and Molecular Biology, 303 E. Chicago Ave., IL 60611, Chicago (United States); Barrea, Raul [Illinois Institute of Technology, Department of Biological Chemical and Physical Sciences, 3101 South Dearborn St., IL 60616, Chicago (United States); Berry, Robert; Binder, Lester I. [Northwestern University, Department of Cell and Molecular Biology, 303 E. Chicago Ave., IL 60611, Chicago (United States); Irving, Thomas; Orgel, Joseph [Illinois Institute of Technology, Department of Biological Chemical and Physical Sciences, 3101 South Dearborn St., IL 60616, Chicago (United States); Vana, Laurel [Northwestern University, Department of Cell and Molecular Biology, 303 E. Chicago Ave., IL 60611, Chicago (United States); Rice, Sarah E., E-mail: s-rice@northwestern.edu [Northwestern University, Department of Cell and Molecular Biology, 303 E. Chicago Ave., IL 60611, Chicago (United States)

    2011-09-01

    We describe an instrument to record X-ray diffraction patterns from diseased regions of human brain tissue by combining an in-line visible light fluorescence microscope with an X-ray diffraction microprobe. We use thiazine red fluorescence to specifically label and detect the filamentous tau protein pathology associated with Pick's disease, as several laboratories have done previously. We demonstrate that thiazine red-enhanced regions within the tissue show periodic structure in X-ray diffraction, which is not observed in healthy tissue. One observed periodicity (4.2 A) is characteristic of cross-beta sheet structure, consistent with previous results from powder diffraction studies performed on purified, dried tau protein.

  10. X-ray diffraction from intact tau aggregates in human brain tissue

    Energy Technology Data Exchange (ETDEWEB)

    Landahl, Eric C.; Antipova, Olga; Bongaarts, Angela; Barrea, Raul; Berry, Robert; Binder, Lester I.; Irving, Thomas; Orgel, Joseph; Vana, Laurel; Rice, Sarah E. (DePaul); (IIT); (NWU)

    2011-09-15

    We describe an instrument to record X-ray diffraction patterns from diseased regions of human brain tissue by combining an in-line visible light fluorescence microscope with an X-ray diffraction microprobe. We use thiazine red fluorescence to specifically label and detect the filamentous tau protein pathology associated with Pick's disease, as several laboratories have done previously. We demonstrate that thiazine red-enhanced regions within the tissue show periodic structure in X-ray diffraction, which is not observed in healthy tissue. One observed periodicity (4.2 {angstrom}) is characteristic of cross-beta sheet structure, consistent with previous results from powder diffraction studies performed on purified, dried tau protein.

  11. Concentration of organochlorines in human brain, liver, and adipose tissue autopsy samples from Greenland

    DEFF Research Database (Denmark)

    Dewailly, Éric; Mulvad, Gert; Pedersen, Henning S.;

    1999-01-01

    Organochlorines are persistent lipophilic compounds that accumulate in Inuit people living in circumpolar countries. Organochlorines accumulate as a result of the Inuits' large consumption of sea mammal fat; however, available data are limited to blood lipids, milk fat, and adipose tissue. We...... report results of organochlorine determination in liver, brain, omental fat, and subcutaneous abdominal fat samples collected from deceased Greenlanders between 1992 and 1994. Eleven chlorinated pesticides and 14 polychlorinated biphenyl congeners were measured in tissue lipid extracts by high......-resolution gas chromatography with electron capture detection. Mean concentrations of polychlorinated biphenyls, 2, 2'-bis(4-chlorophenyl)-1,1-dichloroethylene, ss-hexachlorocyclohexane, hexachlorobenzene, mirex, trans-nonachlor, and oxychlordane in adipose tissue samples from Greenlanders were 3-34-fold higher...

  12. Simultaneous blood-tissue exchange of oxygen, carbon dioxide, bicarbonate, and hydrogen ion.

    Science.gov (United States)

    Dash, Ranjan K; Bassingthwaighte, James B

    2006-07-01

    A detailed nonlinear four-region (red blood cell, plasma, interstitial fluid, and parenchymal cell) axially distributed convection-diffusion-permeation-reaction-binding computational model is developed to study the simultaneous transport and exchange of oxygen (O2) and carbon dioxide (CO2) in the blood-tissue exchange system of the heart. Since the pH variation in blood and tissue influences the transport and exchange of O2 and CO2 (Bohr and Haldane effects), and since most CO2 is transported as HCO3(-) (bicarbonate) via the CO2 hydration (buffering) reaction, the transport and exchange of HCO3(-) and H+ are also simulated along with that of O2 and CO2. Furthermore, the model accounts for the competitive nonlinear binding of O2 and CO2 with the hemoglobin inside the red blood cells (nonlinear O2-CO2 interactions, Bohr and Haldane effects), and myoglobin-facilitated transport of O2 inside the parenchymal cells. The consumption of O2 through cytochrome-c oxidase reaction inside the parenchymal cells is based on Michaelis-Menten kinetics. The corresponding production of CO2 is determined by respiratory quotient (RQ), depending on the relative consumption of carbohydrate, protein, and fat. The model gives a physiologically realistic description of O2 transport and metabolism in the microcirculation of the heart. Furthermore, because model solutions for tracer transients and steady states can be computed highly efficiently, this model may be the preferred vehicle for routine data analysis where repetitive solutions and parameter optimization are required, as is the case in PET imaging for estimating myocardial O2 consumption. PMID:16775761

  13. Dual-porosity poroviscoelasticity and quantitative hydromechanical characterization of the brain tissue with experimental hydrocephalus data.

    Science.gov (United States)

    Mehrabian, Amin; Abousleiman, Younane N; Mapstone, Timothy B; El-Amm, Christian A

    2015-11-01

    Hydromechanical brain models often involve constitutive relations which must account for soft tissue deformation and creep, together with the interstitial fluid movement and exchange through capillaries. The interaction of rather unknown mechanisms which produce, absorb, and circulate the cerebrospinal fluid within the central nervous system can further add to their complexity. Once proper models for these phenomena or processes are selected, estimation of the associated parameters could be even more challenging. This paper presents the results of a consistent, coupled poroviscoelastic modeling and characterization of the brain tissue as a dual-porosity system. The model draws from Biot's theory of poroviscoelasticity, and adopts the generalized Kelvin's rheological description of the viscoelastic tissue behavior. While the interstitial space serves as the primary porosity through which the bulk flow of the interstitial fluid occurs, a secondary porosity network comprising the capillaries and venous system allows for its partial absorption into the blood. The correspondence principle is used in deriving a time-dependent analytical solution to the proposed model. It allows for identical poroelastic formulation of the original poroviscoelastic problem in the Laplace transform space. Hydrocephalus generally refers to a class of medical conditions which share the ventricles enlargement as a common feature. A set of published data from induced hydrocephalus and follow-up perfusion of cats' brains is used for quantitative characterization of the proposed model. A selected portion of these data including the ventricular volume and rate of fluid absorption from the perfused brain, together with the forward model solution, is utilized via an inverse problem technique to find proper estimations of the model parameters. Results show significant improvement in model predictions of the experimental data. The convoluted and coupled solution results are presented through the time

  14. Comparing CT perfusion with oxygen partial pressure in a rabbit VX2 soft-tissue tumor model

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate the oxygen partial pressure of the rabbit model of the VX2 tumor using a 64-slice perfusion CT and to compare the results with that obtained using the oxygen microelectrode method. Perfusion CT was performed for 45 successfully constructed rabbit models of a VX2 brain tumor. The perfusion values of the brain tumor region of interest, the blood volume (BV), the time to peak (TTP) and the peak enhancement intensity (PEI) were measured. The results were compared with the partial pressure of oxygen (PO2) of that region of interest obtained using the oxygen microelectrode method. The perfusion values of the brain tumor region of interest in 45 successfully constructed rabbit models of a VX2 brain tumor ranged from 1.3–127.0 (average, 21.1 ± 26.7 ml/min/ml); BV ranged from 1.2–53.5 ml/100g (average, 22.2 ± 13.7 ml/100g); PEI ranged from 8.7–124.6 HU (average, 43.5 ± 28.7 HU); and TTP ranged from 8.2–62.3 s (average, 38.8 ± 14.8 s). The PO2 in the corresponding region ranged from 0.14–47 mmHg (average, 16 ± 14.8 mmHg). The perfusion CT positively correlated with the tumor PO2, which can be used for evaluating the tumor hypoxia in clinical practice. (author)

  15. The role of tissue oxygen tension in the control of local blood flow in the microcirculation of skeletal muscles

    DEFF Research Database (Denmark)

    Ngo, Thuc Anh

    2010-01-01

    In the microcirculation blood flow is highly regulated dependent on the metabolic activity of the tissues. Among several mechanisms, mechanisms involved in the coupling of changes in tissue oxygen tension due to changes in the metabolic activity of the tissue play an important role. In the systemic...... (inhibitor of KATP channels) in the superfusate abolished both vasodilatation and constriction to low and high oxygen superfusate, indicating that KATP channels are involved in both hypoxic vasodilatation and hyperoxic vasoconstriction. Red blood cells (RBCs) have been proposed to release ATP and...... as in the intact blood-perfused arteriole. This indicates that RBCs are not essential for hypoxic vasodilatation. In addition several potential pathways were evaluated. Application of DPCPX (inhibitor of adenosine A1 and A2 receptors) and L-NAME (inhibitor of NO-synthase) did not affect vasomotor responses to low...

  16. The effect of X-ray on the distribution of biogenic monoamines in the brain tissue

    International Nuclear Information System (INIS)

    The role of biogenic monoamines in immuno-adaptation reaction of animal organism to radiation, in increase of organism radiostability and in studying damage effect of ionizing radiation is investigated. Rat brain was an object of observations. Rats were once X-irradiated at the dose of 0.8 and 1.2 Gr. Assay samples were taken in 10 minutes, 2, 24, 48 hours, 5 and 7 days after radiation. It was clarified that noticeable variations of serotonin, adrenalin and dofamin content were observed in first hours after radiation in hemisphere cortex, medulla oblongata, hypothalamus and cerebellum. The observed phenomena ever more aggravate with progress of radiation sickness. Character and depth of shifts in monoamine distribution are not found to depend on radiation dose only but on chemical structure of neurons of the investigated section as well. The results of studies permit to consider quantitative shifts in distribution of biogenic amines in brain tissue after radiation as one of the factors promoting increase of endogenic defence resources and increasing stability of the irradiated organism. Besides, it is supposed that these shifts result from local distortion of metabolic processes in brain tissue and general somatic shifts progressing at acute radiation sickness

  17. Brain Metastasis in Bone and Soft Tissue Cancers: A Review of Incidence, Interventions, and Outcomes

    Directory of Open Access Journals (Sweden)

    Faris Shweikeh

    2014-01-01

    Full Text Available Bone and soft tissue malignancies account for a small portion of brain metastases. In this review, we characterize their incidence, treatments, and prognosis. Most of the data in the literature is based on case reports and small case series. Less than 5% of brain metastases are from bone and soft tissue sarcomas, occurring most commonly in Ewing’s sarcoma, malignant fibrous tumors, and osteosarcoma. Mean interval from initial cancer diagnosis to brain metastasis is in the range of 20–30 months, with most being detected before 24 months (osteosarcoma, Ewing sarcoma, chordoma, angiosarcoma, and rhabdomyosarcoma, some at 24–36 months (malignant fibrous tumors, malignant peripheral nerve sheath tumors, and alveolar soft part sarcoma, and a few after 36 months (chondrosarcoma and liposarcoma. Overall mean survival ranges between 7 and 16 months, with the majority surviving < 12 months (Ewing’s sarcoma, liposarcoma, malignant fibrous tumors, malignant peripheral nerve sheath tumors, angiosarcoma and chordomas. Management is heterogeneous involving surgery, radiosurgery, radiotherapy, and chemotherapy. While a survival advantage may exist for those given aggressive treatment involving surgical resection, such patients tended to have a favorable preoperative performance status and minimal systemic disease.

  18. Scattering of Sculpted Light in Intact Brain Tissue, with implications for Optogenetics.

    Science.gov (United States)

    Favre-Bulle, Itia A; Preece, Daryl; Nieminen, Timo A; Heap, Lucy A; Scott, Ethan K; Rubinsztein-Dunlop, Halina

    2015-01-01

    Optogenetics uses light to control and observe the activity of neurons, often using a focused laser beam. As brain tissue is a scattering medium, beams are distorted and spread with propagation through neural tissue, and the beam's degradation has important implications in optogenetic experiments. To address this, we present an analysis of scattering and loss of intensity of focused laser beams at different depths within the brains of zebrafish larvae. Our experimental set-up uses a 488 nm laser and a spatial light modulator to focus a diffraction-limited spot of light within the brain. We use a combination of experimental measurements of back-scattered light in live larvae and computational modelling of the scattering to determine the spatial distribution of light. Modelling is performed using the Monte Carlo method, supported by generalised Lorenz-Mie theory in the single-scattering approximation. Scattering in areas rich in cell bodies is compared to that of regions of neuropil to identify the distinct and dramatic contributions that cell nuclei make to scattering. We demonstrate the feasibility of illuminating individual neurons, even in nucleus-rich areas, at depths beyond 100 μm using a spatial light modulator in combination with a standard laser and microscope optics. PMID:26108566

  19. Unified model of brain tissue microstructure dynamically binds diffusion and osmosis with extracellular space geometry

    Science.gov (United States)

    Yousefnezhad, Mohsen; Fotouhi, Morteza; Vejdani, Kaveh; Kamali-Zare, Padideh

    2016-09-01

    We present a universal model of brain tissue microstructure that dynamically links osmosis and diffusion with geometrical parameters of brain extracellular space (ECS). Our model robustly describes and predicts the nonlinear time dependency of tortuosity (λ =√{D /D* } ) changes with very high precision in various media with uniform and nonuniform osmolarity distribution, as demonstrated by previously published experimental data (D = free diffusion coefficient, D* = effective diffusion coefficient). To construct this model, we first developed a multiscale technique for computationally effective modeling of osmolarity in the brain tissue. Osmolarity differences across cell membranes lead to changes in the ECS dynamics. The evolution of the underlying dynamics is then captured by a level set method. Subsequently, using a homogenization technique, we derived a coarse-grained model with parameters that are explicitly related to the geometry of cells and their associated ECS. Our modeling results in very accurate analytical approximation of tortuosity based on time, space, osmolarity differences across cell membranes, and water permeability of cell membranes. Our model provides a unique platform for studying ECS dynamics not only in physiologic conditions such as sleep-wake cycles and aging but also in pathologic conditions such as stroke, seizure, and neoplasia, as well as in predictive pharmacokinetic modeling such as predicting medication biodistribution and efficacy and novel biomolecule development and testing.

  20. Scattering of Sculpted Light in Intact Brain Tissue, with implications for Optogenetics

    Science.gov (United States)

    Favre-Bulle, Itia A.; Preece, Daryl; Nieminen, Timo A.; Heap, Lucy A.; Scott, Ethan K.; Rubinsztein-Dunlop, Halina

    2015-06-01

    Optogenetics uses light to control and observe the activity of neurons, often using a focused laser beam. As brain tissue is a scattering medium, beams are distorted and spread with propagation through neural tissue, and the beam’s degradation has important implications in optogenetic experiments. To address this, we present an analysis of scattering and loss of intensity of focused laser beams at different depths within the brains of zebrafish larvae. Our experimental set-up uses a 488 nm laser and a spatial light modulator to focus a diffraction-limited spot of light within the brain. We use a combination of experimental measurements of back-scattered light in live larvae and computational modelling of the scattering to determine the spatial distribution of light. Modelling is performed using the Monte Carlo method, supported by generalised Lorenz-Mie theory in the single-scattering approximation. Scattering in areas rich in cell bodies is compared to that of regions of neuropil to identify the distinct and dramatic contributions that cell nuclei make to scattering. We demonstrate the feasibility of illuminating individual neurons, even in nucleus-rich areas, at depths beyond 100 μm using a spatial light modulator in combination with a standard laser and microscope optics.

  1. Protective effect of DL-3-n-Butylphthalide on radiation injury of rat brain tissue

    International Nuclear Information System (INIS)

    Objective: To investigate the protective effect and its mechanism of DL-3-n-Butylphthalide on the brain damage in rats following whole brain irradiation. Methods: A total of 120 male Sprague Dawley rats were randomly divided into sham-irradiation group, irradiation group and DL-3-n-Butylphthalide group. The model of whole-brain irradiation was established by exposing rat brain to 4 MeV X-rays with a single-dose of 10 Gy. The rats were intraperitoneally injected with DL-3-n-Butylphthalide at the dosages of 0.3, 1.0, and 3.0 mg/kg once a day. The contents of malondialdehyde and super oxide dismutase activity were measured, while the expressions of apoptosis-associated genes and the ultrastructural changes in hippocampus were examined by immunohistochemistry staining and electron microscope, respectively. Results: After irradiation, the content of malondialdehyde and the expression of apoptosis gene bax in rat brain tissue increased while the activity of super oxide dismutase (SOD) and the expression of anti-apoptosis gene bcl-2 decreased. Apoptosis was also observed in the neurons of hippocampus CA1. Compared with irradiation group, the content of malondialdehyde and the expression of bax gene in the DL-3-n-Butylphthalide group wen significantly reduced (t=-3.89 - -1.96, 2.72-3.48, P<0.05), while the activity of SOD and bcl-2 gene were significantly elevated (t=2.94-3.76, -3.18 - -2.08, P<0.05), and the injury degree of neuron structure in the DL-3-n-Butylphthalide group was slighter than that in the irradiation group. Conclusions: DL-3-n-Butylphthalide executes protective effects in a dose-dependent manner against the radiation injury in rats brain by reducing the induction of malondialdehyde, raising the activity of SOD and inhibiting the generation of apoptosis. (authors)

  2. Effect of hyperbaric oxygen preconditioning on the expressions of B cell lymphoma/lewkmia-2 and Bcl-2 associated X protein in the brain tissue of rats with decompression sickness%高压氧预处理对减压病大鼠脑组织B细胞淋巴瘤/白血病基因-2蛋白及相关X蛋白表达的影响

    Institute of Scientific and Technical Information of China (English)

    李娅; 岳荣; 王文岚; 薛莉; 任杰; 谢小萍; 迪力达尔; 李金声

    2014-01-01

    异均有统计学意义(P<0.05).结论 DCS组大鼠大脑皮层区神经元凋亡1d时最严重,海马区10 d时最明显;HBO预处理可以减轻减压对大鼠脑组织的病理损伤,减轻神经细胞的变性坏死,抑制线粒体途径的细胞凋亡.%Objective To investigate the effect of hyperbaric oxygen (HBO) preconditioning on the expressions of B cell lymphoma/lewkmia-2 (Bcl-2),Bcl-2 associated X protein (Bax) and cysteine aspartic acid specific protease-3 (Caspase-3) in the brain tissue of rats with decompression sickness.Methods Seventy-two male healthy Sprague-Dawley rats were randomly divided into the normal control,the HBO preconditioning group (or HBO group),the decompression sickness group (or the DCS group).Four time points (at days 1,5,7 and 10) were set for each subgroup,which consisted of 6 animals.Pathological changes in the brain tissue,following development of the decompression sickness model,were observed with HE staining,and the expressions of Bcl-2,Bax and Caspase-3 were detected with immunohistochemistry in various subgroups.Results (1) For the animals in the HBO and DCS groups,the state of illness was classified as mild and moderate (grade 1-3).(2) HE staining revealed that a large loose area in the rat cerebral cortex of the DCS group was detected,cortical and hippocampus neurons displayed a triangular degeneration and necrosis,cellular atrophy,volume reduction and degeneration,chromatin condensation or even fragmentation.For the animals in the HBO group,necrotic neuron degeneration and necrosis obviously alleviated.(3) At days 1,5 and 7,the expressions of Bcl-2 positive cells for the DCS group were (89.5 ± 15.60),(176.4 ± 10.22)and (265.52± 15.74) respectively,which were significantly lower than those in the control group (408.67 ± 29.57),with statistical significance (P < 0.05),while on the other hand,the expressions of Bcl-2 positive cells for the HBO group were (179.64 ± 12.21),(253.91 ± 14.00) and (341.15 ± 13.52) respectively,which were

  3. Effects of formalin fixation on tissue optical properties of in-vitro brain samples

    Science.gov (United States)

    Anand, Suresh; Cicchi, Riccardo; Martelli, Fabrizio; Giordano, Flavio; Buccoliero, Anna Maria; Guerrini, Renzo; Pavone, Francesco S.

    2015-03-01

    Application of light spectroscopy based techniques for the detection of cancers have emerged as a promising approach for tumor diagnostics. In-vivo or freshly excised samples are normally used for point spectroscopic studies. However, ethical issues related to in-vivo studies, rapid decay of surgically excised tissues and sample availability puts a limitation on in-vivo and in-vitro studies. There has been a few studies reported on the application of formalin fixed samples with good discrimination capability. Usually formalin fixation is performed to prevent degradation of tissues after surgical resection. Fixing tissues in formalin prevents cell death by forming cross-linkages with proteins. Previous investigations have revealed that washing tissues fixed in formalin using phosphate buffered saline is known to reduce the effects of formalin during spectroscopic measurements. But this could not be the case with reflectance measurements. Hemoglobin is a principal absorbing medium in biological tissues in the visible range. Formalin fixation causes hemoglobin to seep out from red blood cells. Also, there could be alterations in the refractive index of tissues when fixed in formalin. In this study, we propose to investigate the changes in tissue optical properties between freshly excised and formalin fixed brain tissues. The results indicate a complete change in the spectral profile in the visible range where hemoglobin has its maximum absorption peaks. The characteristic bands of oxy-hemoglobin at 540, 580 nm and deoxy-hemoglobin at 555 nm disappear in the case of samples fixed in formalin. In addition, an increased spectral intensity was observed for the wavelengths greater than 650 nm where scattering phenomena are presumed to dominate.

  4. Prion Protein Deficiency Causes Diverse Proteome Shifts in Cell Models That Escape Detection in Brain Tissue

    Science.gov (United States)

    Mehrabian, Mohadeseh; Brethour, Dylan; Williams, Declan; Wang, Hansen; Arnould, Hélène; Schneider, Benoit; Schmitt-Ulms, Gerold

    2016-01-01

    A popular method for studying the function of a given protein is to generate and characterize a suitable model deficient for its expression. For the prion protein (PrP), best known for its role in several invariably fatal neurodegenerative diseases, a natural choice, therefore, would be to undertake such studies with brain samples. We recently documented the surprising observation that PrP deficiency caused a loss or enhancement of NCAM1 polysialylation, dependent on the cell model used. To identify possible causes for this disparity, we set out to systematically investigate the consequence of PrP deficiency on the global proteome in brain tissue and in four distinct cell models. Here we report that PrP deficiency causes robust but surprisingly divergent changes to the global proteomes of cell models but has no discernible impact on the global brain proteome. Amongst >1,500 proteins whose levels were compared in wild-type and PrP-deficient models, members of the MARCKS protein family exhibited pronounced, yet cell model-dependent changes to their steady-state levels. Follow-up experiments revealed that PrP collaborates with members of the MARCKS protein family in its control of NCAM1 polysialylation. We conclude that the physiological function of PrP may be masked in analyses of complex brain samples but its cell-type specific influence on a lipid raft-based NCAM1-related cell biology comes to the fore in investigations of specific cell types. PMID:27327609

  5. Prion Protein Deficiency Causes Diverse Proteome Shifts in Cell Models That Escape Detection in Brain Tissue.

    Science.gov (United States)

    Mehrabian, Mohadeseh; Brethour, Dylan; Williams, Declan; Wang, Hansen; Arnould, Hélène; Schneider, Benoit; Schmitt-Ulms, Gerold

    2016-01-01

    A popular method for studying the function of a given protein is to generate and characterize a suitable model deficient for its expression. For the prion protein (PrP), best known for its role in several invariably fatal neurodegenerative diseases, a natural choice, therefore, would be to undertake such studies with brain samples. We recently documented the surprising observation that PrP deficiency caused a loss or enhancement of NCAM1 polysialylation, dependent on the cell model used. To identify possible causes for this disparity, we set out to systematically investigate the consequence of PrP deficiency on the global proteome in brain tissue and in four distinct cell models. Here we report that PrP deficiency causes robust but surprisingly divergent changes to the global proteomes of cell models but has no discernible impact on the global brain proteome. Amongst >1,500 proteins whose levels were compared in wild-type and PrP-deficient models, members of the MARCKS protein family exhibited pronounced, yet cell model-dependent changes to their steady-state levels. Follow-up experiments revealed that PrP collaborates with members of the MARCKS protein family in its control of NCAM1 polysialylation. We conclude that the physiological function of PrP may be masked in analyses of complex brain samples but its cell-type specific influence on a lipid raft-based NCAM1-related cell biology comes to the fore in investigations of specific cell types.

  6. Fiber-based tissue identification for electrode placement in deep brain stimulation neurosurgery (Conference Presentation)

    Science.gov (United States)

    DePaoli, Damon T.; Lapointe, Nicolas; Goetz, Laurent; Parent, Martin; Prudhomme, Michel; Cantin, Léo.; Galstian, Tigran; Messaddeq, Younès.; Côté, Daniel C.

    2016-03-01

    Deep brain stimulation's effectiveness relies on the ability of the stimulating electrode to be properly placed within a specific target area of the brain. Optical guidance techniques that can increase the accuracy of the procedure, without causing any additional harm, are therefore of great interest. We have designed a cheap optical fiber-based device that is small enough to be placed within commercially available DBS stimulating electrodes' hollow cores and that is capable of sensing biological information from the surrounding tissue, using low power white light. With this probe we have shown the ability to distinguish white and grey matter as well as blood vessels, in vitro, in human brain samples and in vivo, in rats. We have also repeated the in vitro procedure with the probe inserted in a DBS stimulating electrode and found the results were in good agreement. We are currently validating a second fiber optic device, with micro-optical components, that will result in label free, molecular level sensing capabilities, using CARS spectroscopy. The final objective will be to use this data in real time, during deep brain stimulation neurosurgery, to increase the safety and accuracy of the procedure.

  7. A white matter lesion-filling approach to improve brain tissue volume measurements

    Directory of Open Access Journals (Sweden)

    Sergi Valverde

    2014-01-01

    Full Text Available Multiple sclerosis white matter (WM lesions can affect brain tissue volume measurements of voxel-wise segmentation methods if these lesions are included in the segmentation process. Several authors have presented different techniques to improve brain tissue volume estimations by filling WM lesions before segmentation with intensities similar to those of WM. Here, we propose a new method to refill WM lesions, where contrary to similar approaches, lesion voxel intensities are replaced by random values of a normal distribution generated from the mean WM signal intensity of each two-dimensional slice. We test the performance of our method by estimating the deviation in tissue volume between a set of 30 T1-w 1.5 T and 30 T1-w 3 T images of healthy subjects and the same images where: WM lesions have been previously registered and afterwards replaced their voxel intensities to those between gray matter (GM and WM tissue. Tissue volume is computed independently using FAST and SPM8. When compared with the state-of-the-art methods, on 1.5 T data our method yields the lowest deviation in WM between original and filled images, independently of the segmentation method used. It also performs the lowest differences in GM when FAST is used and equals to the best method when SPM8 is employed. On 3 T data, our method also outperforms the state-of-the-art methods when FAST is used while performs similar to the best method when SPM8 is used. The proposed technique is currently available to researchers as a stand-alone program and as an SPM extension.

  8. Effects of isomers of apomorphines on dopamine receptors in striatal and limbic tissue of rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Kula, N.S.; Baldessarini, R.J.; Bromley, S.; Neumeyer, J.L.

    1985-09-16

    The optical isomers of apomorphine (APO) and N-propylnorapomorphine (NPA) were interacted with three biochemical indices of dopamine (Da) receptors in extrapyramidal and limbic preparations of rat brain tissues. There were consistent isomeric preferences for the R(-) configuration of both DA analogs in stimulation adenylate cyclase (D-1 sites) and in competing for high affinity binding of /sup 3/H-spiroperidol (D-2 sites) and of /sup 3/H-ADTN (DA agonist binding sites) in striatal tissue, with lesser isomeric differences in the limbic tissue. The S(+) apomorphines did not inhibit stimulation of adenylate cyclase by DA. The tendency for greater activity of higher apparent affinity of R(-) apomorphines in striatum may reflect the evidently greater abundance of receptor sites in that region. There were only small regional differences in interactions of the apomorphine isomers with all three receptor sites, except for a strong preference of (-)NPA for striatal D-2 sites. These results do not parallel our recent observations indicating potent and selective antidopaminergic actions of S(+) apomorphines in the rat limbic system. They suggest caution in assuming close parallels between current biochemical functional, especially behavioral, methods of evaluating dopamine receptors of mammalian brain.

  9. MR brain scan tissues and structures segmentation: local cooperative Markovian agents and Bayesian formulation

    International Nuclear Information System (INIS)

    Accurate magnetic resonance brain scan segmentation is critical in a number of clinical and neuroscience applications. This task is challenging due to artifacts, low contrast between tissues and inter-individual variability that inhibit the introduction of a priori knowledge. In this thesis, we propose a new MR brain scan segmentation approach. Unique features of this approach include (1) the coupling of tissue segmentation, structure segmentation and prior knowledge construction, and (2) the consideration of local image properties. Locality is modeled through a multi-agent framework: agents are distributed into the volume and perform a local Markovian segmentation. As an initial approach (LOCUS, Local Cooperative Unified Segmentation), intuitive cooperation and coupling mechanisms are proposed to ensure the consistency of local models. Structures are segmented via the introduction of spatial localization constraints based on fuzzy spatial relations between structures. In a second approach, (LOCUS-B, LOCUS in a Bayesian framework) we consider the introduction of a statistical atlas to describe structures. The problem is reformulated in a Bayesian framework, allowing a statistical formalization of coupling and cooperation. Tissue segmentation, local model regularization, structure segmentation and local affine atlas registration are then coupled in an EM framework and mutually improve. The evaluation on simulated and real images shows good results, and in particular, a robustness to non-uniformity and noise with low computational cost. Local distributed and cooperative MRF models then appear as a powerful and promising approach for medical image segmentation. (author)

  10. Detection of constitutive and inducible HSP70 proteins in formalin fixed human brain tissue.

    Science.gov (United States)

    Preusse-Prange, A; Modrow, J-H; Schwark, T; von Wurmb-Schwark, N

    2014-02-01

    The investigation of formalin fixed and paraffin embedded tissue is a routine method in forensic histology. Since these samples are usually stored for decades they provide a unique tissue bank for different scientific issues. In the past, numerous studies were conducted using different kinds of paraffin embedded tissues. However, it is well known that formalin affects macromolecules and thus might hamper reliable and reproducible molecular experiments. The aim of this study was to find out if the treatment with formalin has a negative effect on different protein detection methods and additionally to define the dimension of those possible deleterious effects. We incubated brain tissue samples in formalin for up to three months. After incubation, the samples were analyzed using immunohistochemistry (IHC) and Western blotting to specifically detect and quantify members of the HSP70 superfamily (heat shock proteins). Our study shows that the Western blot analysis of formalin fixed tissues does not allow a reliable detection of proteins at all, while a reproducible detection by IHC was still possible after one month of incubation.

  11. Prevention of radiation induced normal tissue damage by cytokines and hyperbaric oxygen

    International Nuclear Information System (INIS)

    Purpose/Objective: Radiation therapy (XRT) is an effective cancer treatment. A goal of therapy is minimization of side effects. Bone growth after XRT of children is one limiting normal tissue tolerance. The goal of the current experiment is to identify the possible protective effect of hyperbaric oxygen (HBO) and basic fibroblast growth factor (FGF) on bone growth after lower extremity radiation. Material and Methods: 170 five weeks old female C3H mice were divided into 17 study groups. Groups 1-4 are controls which received XRT at 0, 10, 20, and 30 Gy single fraction without subsequent HBO. Groups 5-7 had XRT at 10 Gy with HBO at weeks 1-4, weeks 5-8, and weeks 9-12 after XRT. Groups 8-10 had XRT at 20 Gy with HBO at weeks 1-4, weeks 5-8, and weeks 9-12 after XRT. Groups 11-13 had XRT at 30 Gy with HBO at weeks 1-4, weeks 5-8, and weeks 9-12 after XRT. Groups 14-17 had XRT at 30 Gy and iv FGF with or without HBO at weeks 1-4 (groups 14, 15), and at weeks 5-8 (groups 16, 17) after XRT. Using fluoroscopy, the animals were positioned so that the beam was directed to irradiate the entire right hindlimb, including the majority of the femur. Dosimetry was confirmed by TLD in mouse phantoms. HBO treatments were given 5 days per week for 4 weeks to each study group using 2 ATA (max. 15 PSI) of 100% oxygen for 3 hours/day. FGF was given intravenously at 6 μg twice a week for 4 weeks. X-ray films were taken to measure the leg (tibia and femur) length of animals before and 18 weeks after radiation. The acute and chronic side effects of skin in the irradiated area were checked daily according to standard criteria. The leg bones and soft tissue were collected at the end of experiment for histologic study. Result: HBO significantly reduces the retardation of bone growth induced by XRT for 10 and 20 Gy groups. For example, at the 18th week, leg length discrepancy is 0.0±1.6% for control, 4.2±1.3% for 10 Gy, and 8.2±1.8% for 20 Gy. HBO in 10 Gy groups decreased these

  12. Characterization of positron emission tomography hypoxia tracer uptake and tissue oxygenation via electrochemical modeling

    Energy Technology Data Exchange (ETDEWEB)

    Bowen, Stephen R., E-mail: srbowen@wisc.edu [University of Wisconsin School of Medicine and Public Health, Department of Medical Physics, Madison, WI 53706 (United States); Kogel, Albert J. van der [University Medical Centre St. Radboud, Nijmegen (Netherlands); Nordsmark, Marianne [Aarhus University Hospital, Department of Experimental Clinical Oncology, Aarhus (Denmark); Bentzen, Soren M. [University of Wisconsin School of Medicine and Public Health, Department of Medical Physics, Madison, WI 53706 (United States); University of Wisconsin School of Medicine and Public Health, Department of Human Oncology, Clinical Sciences Center, Madison, WI 53792 (United States); Jeraj, Robert [University of Wisconsin School of Medicine and Public Health, Department of Medical Physics, Madison, WI 53706 (United States); University of Wisconsin School of Medicine and Public Health, Department of Human Oncology, Clinical Sciences Center, Madison, WI 53792 (United States); Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)

    2011-08-15

    Purpose: Unique uptake and retention mechanisms of positron emission tomography (PET) hypoxia tracers make in vivo comparison between them challenging. Differences in imaged uptake of two common hypoxia radiotracers, [{sup 61}Cu]Cu-ATSM and [{sup 18}F]FMISO, were characterized via computational modeling to address these challenges. Materials and Methods: An electrochemical formalism describing bioreductive retention mechanisms of these tracers under steady-state conditions was adopted to relate time-averaged activity concentration to tissue partial oxygen tension (PO{sub 2}), a common metric of hypoxia. Chemical equilibrium constants of product concentration to reactant concentration ratios were determined from free energy changes and reduction potentials of pertinent reactions reported in the literature. Resulting transformation functions between tracer uptake and PO{sub 2} were compared against measured values in preclinical models. Additionally, calculated PO{sub 2} distributions from imaged Cu-ATSM tracer activity concentrations of 12 head and neck squamous cell carcinoma (HNSCC) patients were validated against microelectrode PO{sub 2} measurements in 69 HNSCC patients. Results: Both Cu-ASTM- and FMISO-modeled PO{sub 2} transformation functions were in agreement with preclinical measured values within single-deviation confidence intervals. High correlation (r{sup 2}=0.94, P<.05) was achieved between modeled PO{sub 2} distributions and measured distributions in the patient populations. On average, microelectrode hypoxia thresholds (2.5 and 5.0 mmHg) corresponded to higher Cu-ATSM uptake [2.5 and 2.0 standardized uptake value (SUV)] and lower FMISO uptake (2.0 and 1.4 SUV). Uncertainties in the models were dominated by variations in the estimated specific activity and intracellular acidity. Conclusions: Results indicated that the high dynamic range of Cu-ATSM uptake was representative of a narrow range of low oxygen tension whose values were dependent on

  13. Astrocyte cultures derived from human brain tissue express angiotensinogen mRNA

    International Nuclear Information System (INIS)

    The authors have identified human cultured cell lines that are useful for studying angiotensinogen gene expression and its regulation in the central nervous system. A model cell system of human central nervous system origin expressing angiotensinogen has not previously been available. Expression of angiotensinogen mRNA appears to be a basal property of noninduced human astrocytes, since astrocytic cell lines derived from human glioblastomas or nonneoplastic human brain tissue invariably produced angiotensinogen mRNA. In situ hybridization histochemistry revealed that angiotensinogen mRNA production was not limited to a subpopulation of astrocytes because >99% of cells in these cultures contained angiotensinogen mRNA. These cell lines will be useful in studies of the molecular mechanisms controlling angiotensin synthesis and the role of biologically active angiotensin in the human brain by allowing the authors to examine regulation of expression of the renin-angiotensin system in human astrocyte cultures

  14. Astrocyte cultures derived from human brain tissue express angiotensinogen mRNA

    Energy Technology Data Exchange (ETDEWEB)

    Milsted, A.; Barna, B.P.; Ransohoff, R.M.; Brosnihan, K.B.; Ferrario, C.M. (Cleveland Clinic Foundation, OH (USA))

    1990-08-01

    The authors have identified human cultured cell lines that are useful for studying angiotensinogen gene expression and its regulation in the central nervous system. A model cell system of human central nervous system origin expressing angiotensinogen has not previously been available. Expression of angiotensinogen mRNA appears to be a basal property of noninduced human astrocytes, since astrocytic cell lines derived from human glioblastomas or nonneoplastic human brain tissue invariably produced angiotensinogen mRNA. In situ hybridization histochemistry revealed that angiotensinogen mRNA production was not limited to a subpopulation of astrocytes because >99% of cells in these cultures contained angiotensinogen mRNA. These cell lines will be useful in studies of the molecular mechanisms controlling angiotensin synthesis and the role of biologically active angiotensin in the human brain by allowing the authors to examine regulation of expression of the renin-angiotensin system in human astrocyte cultures.

  15. Substrate stiffness and oxygen as regulators of stem cell differentiation during skeletal tissue regeneration: a mechanobiological model.

    Directory of Open Access Journals (Sweden)

    Darren Paul Burke

    Full Text Available Extrinsic mechanical signals have been implicated as key regulators of mesenchymal stem cell (MSC differentiation. It has been possible to test different hypotheses for mechano-regulated MSC differentiation by attempting to simulate regenerative events such as bone fracture repair, where repeatable spatial and temporal patterns of tissue differentiation occur. More recently, in vitro studies have identified other environmental cues such as substrate stiffness and oxygen tension as key regulators of MSC differentiation; however it remains unclear if and how such cues determine stem cell fate in vivo. As part of this study, a computational model was developed to test the hypothesis that substrate stiffness and oxygen tension regulate stem cell differentiation during fracture healing. Rather than assuming mechanical signals act directly on stem cells to determine their differentiation pathway, it is postulated that they act indirectly to regulate angiogenesis and hence partially determine the local oxygen environment within a regenerating tissue. Chondrogenesis of MSCs was hypothesized to occur in low oxygen regions, while in well vascularised regions of the regenerating tissue a soft local substrate was hypothesised to facilitate adipogenesis while a stiff substrate facilitated osteogenesis. Predictions from the model were compared to both experimental data and to predictions of a well established computational mechanobiological model where tissue differentiation is assumed to be regulated directly by the local mechanical environment. The model predicted all the major events of fracture repair, including cartilaginous bridging, endosteal and periosteal bony bridging and bone remodelling. It therefore provides support for the hypothesis that substrate stiffness and oxygen play a key role in regulating MSC fate during regenerative events such as fracture healing.

  16. Determinants of renal tissue oxygenation as measured with BOLD-MRI in chronic kidney disease and hypertension in humans.

    Directory of Open Access Journals (Sweden)

    Menno Pruijm

    Full Text Available Experimentally renal tissue hypoxia appears to play an important role in the pathogenesis of chronic kidney disease (CKD and arterial hypertension (AHT. In this study we measured renal tissue oxygenation and its determinants in humans using blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI under standardized hydration conditions. Four coronal slices were selected, and a multi gradient echo sequence was used to acquire T2* weighted images. The mean cortical and medullary R2* values ( = 1/T2* were calculated before and after administration of IV furosemide, a low R2* indicating a high tissue oxygenation. We studied 195 subjects (95 CKD, 58 treated AHT, and 42 healthy controls. Mean cortical R2 and medullary R2* were not significantly different between the groups at baseline. In stimulated conditions (furosemide injection, the decrease in R2* was significantly blunted in patients with CKD and AHT. In multivariate linear regression analyses, neither cortical nor medullary R2* were associated with eGFR or blood pressure, but cortical R2* correlated positively with male gender, blood glucose and uric acid levels. In conclusion, our data show that kidney oxygenation is tightly regulated in CKD and hypertensive patients at rest. However, the metabolic response to acute changes in sodium transport is altered in CKD and in AHT, despite preserved renal function in the latter group. This suggests the presence of early renal metabolic alterations in hypertension. The correlations between cortical R2* values, male gender, glycemia and uric acid levels suggest that these factors interfere with the regulation of renal tissue oxygenation.

  17. Hyperbaric oxygen therapy or hydroxycobalamin attenuates surges in brain interstitial lactate and glucose; and hyperbaric oxygen improves respiratory status in cyanide-intoxicated rats

    DEFF Research Database (Denmark)

    Lawson-Smith, P; Olsen, Niels Vidiendal; Hyldegaard, O

    2011-01-01

    Cyanide (CN) intoxication inhibits cellular oxidative metabolism and may result in brain damage. Hydroxycobalamin (OHCob) is one among other antidotes that may be used following intoxication with CN. Hyperbaric oxygen (HBO2) is recommended when supportive measures or antidotes fail. However...... to four groups receiving potassium CN (KCN) 5.4 mg/kg or vehicle intra-arterially: 1) vehicle-treated control rats; 2) KCN-poisoned rats; 3) KCN-poisoned rats receiving hydroxycobalamin (25 mg); and 4) KCN-poisoned rats treated with HBO2 (284 kPa for 90 minutes). KCN alone caused a prompt increase...

  18. Vasculitis defects by brain SPECT in mixed connective tissue disease. A case report

    International Nuclear Information System (INIS)

    Full text: Cerebrovascular involvement including vasculitis in mixed connective tissue disease (MCTD) is reported to be uncommon. We describe the clinical findings and course of a 45 years old black women followed and diagnosed with depression and cognitive impairment including mental confusion, visual an auditive hallucination. Complete neuropsychological evaluation established the diagnosis of psychotic disorder. Laboratory tests, computed tomography of the skull were completely normal. The patient was referred to a brain SPECT which showed a focal area of decrease regional cerebral blood flow in right parietal-occipital region. Increasing the corticosteroids dose and with the use of neuroleptics, the patient improve clinically and the SPECT turned out to be normal

  19. Experimental study on the toxicity of povidone-iodine solution in brain tissues of rabbits

    OpenAIRE

    Li, Shu-Hua; Wang, Yu; Gao, Hai-Bin; Zhao, Kun; Hou, Yu-Chen; Sun, Wei

    2015-01-01

    Objective: To determine whether Povidone-iodine was toxic to brain tissues by rinsing the cerebral cortex of New Zealand rabbits with Povidone-iodine Solution of different concentrations. Methods: 12 New Zealand rabbits were randomly divided into 4 groups (Group A, B, C and D, 3 rabbits each group). In each group, the left cerebral cortex of rabbits was rinsed with physiological saline after the craniotomy; in Group A and B, the right cerebral cortex of rabbits was also locally rinsed with Po...

  20. Mechanical characterization of brain tissue in compression at dynamic strain rates.

    Science.gov (United States)

    Rashid, Badar; Destrade, Michel; Gilchrist, Michael D

    2012-06-01

    Traumatic brain injury (TBI) occurs when local mechanical load exceeds certain tolerance levels for brain tissue. Extensive research has been done previously for brain matter experiencing compression at quasistatic loading; however, limited data is available to model TBI under dynamic impact conditions. In this research, an experimental setup was developed to perform unconfined compression tests and stress relaxation tests at strain rates ≤90/s. The brain tissue showed a stiffer response with increasing strain rates, showing that hyperelastic models are not adequate. Specifically, the compressive nominal stress at 30% strain was 8.83 ± 1.94, 12.8 ± 3.10 and 16.0 ± 1.41 kPa (mean ± SD) at strain rates of 30, 60 and 90/s, respectively. Relaxation tests were also conducted at 10%-50% strain with the average rise time of 10 ms, which can be used to derive time dependent parameters. Numerical simulations were performed using one-term Ogden model with initial shear modulus μ(o)=6.06±1.44, 9.44 ± 2.427 and 12.64 ± 1.227 kPa (mean ± SD) at strain rates of 30, 60 and 90/s, respectively. A separate set of bonded and lubricated tests were also performed under the same test conditions to estimate the friction coefficient μ, by adopting combined experimental-computational approach. The values of μ were 0.1 ± 0.03 and 0.15 ± 0.07 (mean ± SD) at 30 and 90/s strain rates, respectively, indicating that pure slip conditions cannot be achieved in unconfined compression tests even under fully lubricated test conditions. The material parameters obtained in this study will help to develop biofidelic human brain finite element models, which can subsequently be used to predict brain injuries under impact conditions. PMID:22520416

  1. Brain herniation

    Science.gov (United States)

    ... herniation; Uncal herniation; Subfalcine herniation; Tonsillar herniation; Herniation - brain ... Brain herniation occurs when something inside the skull produces pressure that moves brain tissues. This is most ...

  2. Pediatric brain tumors of neuroepithelial tissue; Hirntumoren des neuroepithelialen Gewebes im Kindesalter

    Energy Technology Data Exchange (ETDEWEB)

    Papanagiotou, P.; Politi, M. [Klinikum Bremen-Mitte/Bremen-Ost, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Bremen (Germany); Bergmann, M. [Klinikum Bremen-Mitte, Institut fuer Klinische Neuropathologie, Bremen (Germany); Pekrun, A. [Klinikum Bremen-Mitte, Klinik fuer Kinder- und Jugendmedizin, paed. Haematologie/Onkologie, Neonatologie, Bremen (Germany); Juergens, K.U. [Klinikum Bremen-Mitte, ZEMODI-Zentrum fuer moderne Diagnostik, MRT, Nuklearmedizin und PET-CT, Bremen (Germany)

    2014-08-15

    Tumors of neuroepithelial tissue represent the largest group of pediatric brain tumors by far and has therefore been divided into several discrete tumor subtypes each corresponding to a specific component of the neuropil. The neuropil contains several subtypes of glial cells, including astrocytes, oligodendrocytes, ependymal cells and modified ependymal cells that form the choroid plexus. This review discusses the imaging aspects of the most common pediatric tumors of neuroepithelial tissue. (orig.) [German] Tumoren des neuroepithelialen Gewebes stellen die mit Abstand groesste Gruppe der paediatrischen Hirntumoren dar und werden je nach deren Ursprung in diversen Subtypen unterteilt. Das Neuropil beinhaltet diverse Subtypen von Gliazellen: Astrozyten, Oligodendrozyten, ependymale Zellen und modifizierte ependymale Zellen, die den Plexus choroideus formen. In diesem Review werden die bildgebenden Aspekte mittels CT und MRT der haeufigsten Tumoren des neuroepithelialen Gewebes diskutiert. (orig.)

  3. Antiviral antibodies stimulate production of reactive oxygen species in cultured canine brain cells infected with canine distemper virus.

    OpenAIRE

    Bürge, T; Griot, C; Vandevelde, M; Peterhans, E

    1989-01-01

    Canine distemper is characterized mainly by respiratory, enteric, and nervous symptoms. Infection of the central nervous system results in demyelination, to which inflammation has been shown to contribute significantly. It has been proposed that macrophages play a major role as effector cells in this process. We report that cultured dog brain cells contain a population of macrophages capable of producing reactive oxygen species as measured by luminol-dependent chemiluminescence. In cultures i...

  4. Single nanoparticle tracking of [Formula: see text]-methyl-d-aspartate receptors in cultured and intact brain tissue.

    Science.gov (United States)

    Varela, Juan A; Ferreira, Joana S; Dupuis, Julien P; Durand, Pauline; Bouchet, Delphine; Groc, Laurent

    2016-10-01

    Recent developments in single-molecule imaging have revealed many biological mechanisms, providing high spatial and temporal resolution maps of molecular events. In neurobiology, these techniques unveiled that plasma membrane neurotransmitter receptors and transporters laterally diffuse at the surface of cultured brain cells. The photostability of bright nanoprobes, such as quantum dots (QDs), has given access to neurotransmitter receptor tracking over long periods of time with a high spatial resolution. However, our knowledge has been restricted to cultured systems, i.e., neurons and organotypic slices, therefore lacking several aspects of the intact brain rheology and connectivity. Here, we used QDs to track single glutamatergic [Formula: see text]-methyl-d-aspartate receptors (NMDAR) in acute brain slices. By delivering functionalized nanoparticles in vivo through intraventricular injections to rats expressing genetically engineered-tagged NMDAR, we successfully tracked the receptors in native brain tissue. Comparing NMDAR tracking to different classical brain preparations (acute brain slices, cultured organotypic brain slices, and cultured neurons) revealed that the surface diffusion properties shared several features and are also influenced by the nature of the extracellular environment. Together, we describe the experimental procedures to track plasma membrane NMDAR in dissociated and native brain tissue, paving the way for investigations aiming at characterizing receptor diffusion biophysics in intact tissue and exploring the physiopathological roles of receptor surface dynamics. PMID:27429996

  5. Quantifying brain tissue volume in multiple sclerosis with automated lesion segmentation and filling

    Directory of Open Access Journals (Sweden)

    Sergi Valverde

    2015-01-01

    Full Text Available Lesion filling has been successfully applied to reduce the effect of hypo-intense T1-w Multiple Sclerosis (MS lesions on automatic brain tissue segmentation. However, a study of fully automated pipelines incorporating lesion segmentation and lesion filling on tissue volume analysis has not yet been performed. Here, we analyzed the % of error introduced by automating the lesion segmentation and filling processes in the tissue segmentation of 70 clinically isolated syndrome patient images. First of all, images were processed using the LST and SLS toolkits with different pipeline combinations that differed in either automated or manual lesion segmentation, and lesion filling or masking out lesions. Then, images processed following each of the pipelines were segmented into gray matter (GM and white matter (WM using SPM8, and compared with the same images where expert lesion annotations were filled before segmentation. Our results showed that fully automated lesion segmentation and filling pipelines reduced significantly the % of error in GM and WM volume on images of MS patients, and performed similarly to the images where expert lesion annotations were masked before segmentation. In all the pipelines, the amount of misclassified lesion voxels was the main cause in the observed error in GM and WM volume. However, the % of error was significantly lower when automatically estimated lesions were filled and not masked before segmentation. These results are relevant and suggest that LST and SLS toolboxes allow the performance of accurate brain tissue volume measurements without any kind of manual intervention, which can be convenient not only in terms of time and economic costs, but also to avoid the inherent intra/inter variability between manual annotations.

  6. Quantifying brain tissue volume in multiple sclerosis with automated lesion segmentation and filling.

    Science.gov (United States)

    Valverde, Sergi; Oliver, Arnau; Roura, Eloy; Pareto, Deborah; Vilanova, Joan C; Ramió-Torrentà, Lluís; Sastre-Garriga, Jaume; Montalban, Xavier; Rovira, Àlex; Lladó, Xavier

    2015-01-01

    Lesion filling has been successfully applied to reduce the effect of hypo-intense T1-w Multiple Sclerosis (MS) lesions on automatic brain tissue segmentation. However, a study of fully automated pipelines incorporating lesion segmentation and lesion filling on tissue volume analysis has not yet been performed. Here, we analyzed the % of error introduced by automating the lesion segmentation and filling processes in the tissue segmentation of 70 clinically isolated syndrome patient images. First of all, images were processed using the LST and SLS toolkits with different pipeline combinations that differed in either automated or manual lesion segmentation, and lesion filling or masking out lesions. Then, images processed following each of the pipelines were segmented into gray matter (GM) and white matter (WM) using SPM8, and compared with the same images where expert lesion annotations were filled before segmentation. Our results showed that fully automated lesion segmentation and filling pipelines reduced significantly the % of error in GM and WM volume on images of MS patients, and performed similarly to the images where expert lesion annotations were masked before segmentation. In all the pipelines, the amount of misclassified lesion voxels was the main cause in the observed error in GM and WM volume. However, the % of error was significantly lower when automatically estimated lesions were filled and not masked before segmentation. These results are relevant and suggest that LST and SLS toolboxes allow the performance of accurate brain tissue volume measurements without any kind of manual intervention, which can be convenient not only in terms of time and economic costs, but also to avoid the inherent intra/inter variability between manual annotations.

  7. Umbilical cord-derived mesenchymal stem cell transplantation combined with hyperbaric oxygen treatment for repair of traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Hai-xiao Zhou; Zhi-gang Liu; Xiao-jiao Liu; Qian-xue Chen

    2016-01-01

    Transplantation of umbilical cord-derived mesenchymal stem cells (UC-MSCs) for repair of traumatic brain injury has been used in the clinic. Hyperbaric oxygen (HBO) treatment has long been widely used as an adjunctive therapy for treating traumatic brain injury. UC-MSC transplantation combined with HBO treatment is expected to yield better therapeutic effects on traumatic brain injury. In this study, we established rat models of severe traumatic brain injury by pressurized lfuid (2.5–3.0 atm impact force). The injured rats were then administered UC-MSC transplantationvia the tail vein in combination with HBO treatment. Compared with monotherapy, aquaporin 4 expression decreased in the injured rat brain, but growth-associated protein-43 expression, calaxon-like structures, and CM-Dil-positive cell number increased. Following combination therapy, however, rat cognitive and neurological function signiifcantly improved. UC-MSC transplantation combined with HBO therapyfor repair of traumatic brain injury shows better therapeutic effects than monotherapy and signiifcantly promotes recovery of neurological functions.

  8. Umbilical cord-derived mesenchymal stem cell transplantation combined with hyperbaric oxygen treatment for repair of traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Hai-xiao Zhou

    2016-01-01

    Full Text Available Transplantation of umbilical cord-derived mesenchymal stem cells (UC-MSCs for repair of traumatic brain injury has been used in the clinic. Hyperbaric oxygen (HBO treatment has long been widely used as an adjunctive therapy for treating traumatic brain injury. UC-MSC transplantation combined with HBO treatment is expected to yield better therapeutic effects on traumatic brain injury. In this study, we established rat models of severe traumatic brain injury by pressurized fluid (2.5-3.0 atm impact force. The injured rats were then administered UC-MSC transplantation via the tail vein in combination with HBO treatment. Compared with monotherapy, aquaporin 4 expression decreased in the injured rat brain, but growth-associated protein-43 expression, calaxon-like structures, and CM-Dil-positive cell number increased. Following combination therapy, however, rat cognitive and neurological function significantly improved. UC-MSC transplantation combined with HBO therapyfor repair of traumatic brain injury shows better therapeutic effects than monotherapy and significantly promotes recovery of neurological functions.

  9. Dynamic, mating-induced gene expression changes in female head and brain tissues of Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Stirling Emma J

    2010-10-01

    Full Text Available Abstract Background Drosophila melanogaster females show changes in behavior and physiology after mating that are thought to maximize the number of progeny resulting from the most recent copulation. Sperm and seminal fluid proteins induce post-mating changes in females, however, very little is known about the resulting gene expression changes in female head and central nervous system tissues that contribute to the post-mating response. Results We determined the temporal gene expression changes in female head tissues 0-2, 24, 48 and 72 hours after mating. Females from each time point had a unique post-mating gene expression response, with 72 hours post-mating having the largest number of genes with significant changes in expression. At most time points, genes expressed in the head fat body that encode products involved in metabolism showed a marked change in expression. Additional analysis of gene expression changes in dissected brain tissues 24 hours post-mating revealed changes in transcript abundance of many genes, notably, the reduced transcript abundance of genes that encode ion channels. Conclusions Substantial changes occur in the regulation of many genes in female head tissues after mating, which might underlie aspects of the female post-mating response. These results provide new insights into the physiological and metabolic changes that accompany changes in female behaviors.

  10. Differences in Cognitive Function of Rats with Traumatic Brain Injuries Following Hyperbaric Oxygen Therapy

    Science.gov (United States)

    Zhang, Xiaonian; Wang, Xiaoyan; Sun, Xinting; Sun, Xiaojing; Zhang, Yue; Zhang, Hao

    2016-01-01

    Background Hyperbaric oxygen (HBO) is a historical therapeutic option in the treatment of various types of brain damage. At present, clinical treatment of hypoxic-ischemic injury is giving priority to cognitive training. The effects of HBO on cognitive dysfunction were observed in a controlled cortical impact (CCI) rat model. Material/Methods Seventy male SD rats were randomly divided into control (n=10) and intervention (n=60) groups. All rats underwent baseline water maze testing 1 day before modeling, and were retested 8 weeks after modeling. The percentage of residence time during escape latency in the target quadrant and the total time were recorded. Data were analyzed by SPSS 16.0 software. P0.05) existed in spatial learning ability in the 3-day and 5-day groups when compared with baseline. The other groups were statistically different by auto-comparison (P0.05) in spatial memory existed in the 5-day and 1-week groups when compared with baseline, while a significant difference was noted in the other groups by self-comparison (P0.05) was noted in the level of expression of growth-associated protein-43 (GAP-43) and synaptophysin (Syn) in the 1-day group compared with the control group. The remaining groups and the control group were statistically different (P<0.05), while the level of expression of GAP-43 and Syn in the 5-day, 1-week, and 2-week groups was significantly different compared with that in the control group (P<0.01). Conclusions If HBO therapy was provided 5–7 days after craniocerebral trauma, there was apparent improvement in cognitive function and neuroplasticity. PMID:27450528

  11. Differences in Cognitive Function of Rats with Traumatic Brain Injuries Following Hyperbaric Oxygen Therapy.

    Science.gov (United States)

    Zhang, Xiaonian; Wang, Xiaoyan; Sun, Xinting; Sun, Xiaojing; Zhang, Yue; Zhang, Hao

    2016-01-01

    BACKGROUND Hyperbaric oxygen (HBO) is a historical therapeutic option in the treatment of various types of brain damage. At present, clinical treatment of hypoxic-ischemic injury is giving priority to cognitive training. The effects of HBO on cognitive dysfunction were observed in a controlled cortical impact (CCI) rat model. MATERIAL AND METHODS Seventy male SD rats were randomly divided into control (n=10) and intervention (n=60) groups. All rats underwent baseline water maze testing 1 day before modeling, and were retested 8 weeks after modeling. The percentage of residence time during escape latency in the target quadrant and the total time were recorded. Data were analyzed by SPSS 16.0 software. P0.05) existed in spatial learning ability in the 3-day and 5-day groups when compared with baseline. The other groups were statistically different by auto-comparison (P0.05) in spatial memory existed in the 5-day and 1-week groups when compared with baseline, while a significant difference was noted in the other groups by self-comparison (P0.05) was noted in the level of expression of growth-associated protein-43 (GAP-43) and synaptophysin (Syn) in the 1-day group compared with the control group. The remaining groups and the control group were statistically different (P<0.05), while the level of expression of GAP-43 and Syn in the 5-day, 1-week, and 2-week groups was significantly different compared with that in the control group (P<0.01). CONCLUSIONS If HBO therapy was provided 5-7 days after craniocerebral trauma, there was apparent improvement in cognitive function and neuroplasticity. PMID:27450528

  12. Imaging of non tumorous and tumorous human brain tissue with full-field optical coherence tomography

    CERN Document Server

    Assayag, Osnath; Devaux, Bertrand; Harms, Fabrice; Pallud, Johan; Chretien, Fabrice; Boccara, Claude; Varlet, Pascale

    2013-01-01

    A prospective study was performed on neurosurgical samples from 18 patients to evaluate the use of Full-Field Optical Coherence Tomography (FF-OCT) in brain tumor diagnosis. FF-OCT captures en face slices of tissue samples at 1\\mum resolution in 3D with a typical 200\\mum imaging depth. A 1cm2 specimen is scanned at a single depth and processed in about 5 minutes. This rapid imaging process is non-invasive and 30 requires neither contrast agent injection nor tissue preparation, which makes it particularly well suited to medical imaging applications. Temporal chronic epileptic parenchyma and brain tumors such as meningiomas, low- grade and high-grade gliomas, and choroid plexus papilloma were imaged. A subpopulation of neurons, myelin fibers and CNS vasculature were clearly identified. Cortex could be discriminated from white matter, but individual glial cells as astrocytes (normal or reactive) or oligodendrocytes were not observable. This study reports for the first time on the feasibility of using FF-OCT in a...

  13. In vitro determination of normal and neoplastic human brain tissue optical properties using inverse adding-doubling.

    Science.gov (United States)

    Gebhart, S C; Lin, W C; Mahadevan-Jansen, A

    2006-04-21

    To complement a project towards the development of real-time optical biopsy for brain tissue discrimination and surgical resection guidance, the optical properties of various brain tissues were measured in vitro and correlated to features within clinical diffuse reflectance tissue spectra measured in vivo. Reflectance and transmission spectra of in vitro brain tissue samples were measured with a single-integrating-sphere spectrometer for wavelengths 400-1300 nm and converted to absorption and reduced scattering spectra using an inverse adding-doubling technique. Optical property spectra were classified as deriving from white matter, grey matter or glioma tissue according to histopathologic diagnosis, and mean absorption and reduced scattering spectra were calculated for the three tissue categories. Absolute reduced scattering and absorption values and their relative differences between histopathological groups agreed with previously reported results with the exception that absorption coefficients were often overestimated, most likely due to biologic variability or unaccounted light loss during reflectance/transmission measurement. Absorption spectra for the three tissue classes were dominated by haemoglobin absorption below 600 nm and water absorption above 900 nm and generally determined the shape of corresponding clinical diffuse reflectance spectra. Reduced scattering spectral shapes followed the power curve predicted by the Rayleigh limit of Mie scattering theory. While tissue absorption governed the shape of clinical diffuse reflectance spectra, reduced scattering determined their relative emission intensities between the three tissue categories. PMID:16585842

  14. Prion Protein Deficiency Causes Diverse Proteome Shifts in Cell Models That Escape Detection in Brain Tissue.

    Directory of Open Access Journals (Sweden)

    Mohadeseh Mehrabian

    Full Text Available A popular method for studying the function of a given protein is to generate and characterize a suitable model deficient for its expression. For the prion protein (PrP, best known for its role in several invariably fatal neurodegenerative diseases, a natural choice, therefore, would be to undertake such studies with brain samples. We recently documented the surprising observation that PrP deficiency caused a loss or enhancement of NCAM1 polysialylation, dependent on the cell model used. To identify possible causes for this disparity, we set out to systematically investigate the consequence of PrP deficiency on the global proteome in brain tissue and in four distinct cell models. Here we report that PrP deficiency causes robust but surprisingly divergent changes to the global proteomes of cell models but has no discernible impact on the global brain proteome. Amongst >1,500 proteins whose levels were compared in wild-type and PrP-deficient models, members of the MARCKS protein family exhibited pronounced, yet cell model-dependent changes to their steady-state levels. Follow-up experiments revealed that PrP collaborates with members of the MARCKS protein family in its control of NCAM1 polysialylation. We conclude that the physiological function of PrP may be masked in analyses of complex brain samples but its cell-type specific influence on a lipid raft-based NCAM1-related cell biology comes to the fore in investigations of specific cell types.

  15. Brain energy metabolism: development and application of novel live methodologies

    OpenAIRE

    Bennett, Rachel

    2012-01-01

    This thesis investigates methods of studying brain energy metabolism with a specific focus on the substrates oxygen and glucose. It details the in vitro development and in vivo characterisation of microelectrochemical sensors for the detection of brain tissue oxygen, and the in vivo characterisation of oxygen and glucose electrodes in the hippocampus utilising the technique of long-term in vivo electrochemistry (LIVE). Chapter 1 introduces the brain, energy metabolism and neurochemical ana...

  16. Establishment of a Stable PrPSc Panel from Brain Tissues of Experimental Hamsters with Scrapie Strain 263K

    Institute of Scientific and Technical Information of China (English)

    BAO-YUN ZHANG; CHAN TIAN; JUN HAN; CHEN GAO; QI SHI; JIAN-MING CHEN; HUI-YING JIANG; WEI ZHOU; XIAO-Ping DONG

    2009-01-01

    Objective To establish a stable PrPSc panel from brain tissues of experimental hamsters infected with scrapie agent 263K for evaluating diagnostic techniques of human and animals' prion diseases. Methods Thirty brain tissue samples from hamsters intracerebrally infected with scrapie strain 263K and another 30 samples from normal hamsters were selected to prepare 10%, 1%, and 0.5% brain homogenates, which were aliquoted into stocks. PrPSc in each brain homogenate was determined by proteinase K digestions followed by Western blot assay and partially by immunohistochemistry. Stability and glycoforms of PrPSc were repeatedly detected by PrPSc-specific Western blots in half a year and 3 years later. Results PrPSc signals were observed in all 10% brain homogenates of infected hamsters. Twenty out of 30 stocks and 19 out of 30 stocks were PrPSc positive in 1% and 0.5% brain homogenatesof infected hamsters, respectively. Twenty-seven out of 30 stocks presented three positive bands in 10% brain homogenates, whereas none of 1% and 0.5% homogenates contained 3 bands. The detection of PrPSc-specific signals stored in half a year and 3 years later demonstrated that the ratio of PrPSc positive samples and glycoforms was almost unchanged. All normal hamsters' brain homogenates were PrPSc negative. Conclusion A PrPSc panel of prion disease can be established, which displays reliably stable PrPSc-specific signals and glycoforms.

  17. Computational deconvolution of genome wide expression data from Parkinson's and Huntington's disease brain tissues using population-specific expression analysis

    Science.gov (United States)

    Capurro, Alberto; Bodea, Liviu-Gabriel; Schaefer, Patrick; Luthi-Carter, Ruth; Perreau, Victoria M.

    2015-01-01

    The characterization of molecular changes in diseased tissues gives insight into pathophysiological mechanisms and is important for therapeutic development. Genome-wide gene expression analysis has proven valuable for identifying biological processes in neurodegenerative diseases using post mortem human brain tissue and numerous datasets are publically available. However, many studies utilize heterogeneous tissue samples consisting of multiple cell types, all of which contribute to global gene expression values, confounding biological interpretation of the data. In particular, changes in numbers of neuronal and glial cells occurring in neurodegeneration confound transcriptomic analyses, particularly in human brain tissues where sample availability and controls are limited. To identify cell specific gene expression changes in neurodegenerative disease, we have applied our recently published computational deconvolution method, population specific expression analysis (PSEA). PSEA estimates cell-type-specific expression values using reference expression measures, which in the case of brain tissue comprises mRNAs with cell-type-specific expression in neurons, astrocytes, oligodendrocytes and microglia. As an exercise in PSEA implementation and hypothesis development regarding neurodegenerative diseases, we applied PSEA to Parkinson's and Huntington's disease (PD, HD) datasets. Genes identified as differentially expressed in substantia nigra pars compacta neurons by PSEA were validated using external laser capture microdissection data. Network analysis and Annotation Clustering (DAVID) identified molecular processes implicated by differential gene expression in specific cell types. The results of these analyses provided new insights into the implementation of PSEA in brain tissues and additional refinement of molecular signatures in human HD and PD. PMID:25620908

  18. Spontaneous calcium waves in Bergman glia increase with age and hypoxia and may reduce tissue oxygen

    OpenAIRE

    Mathiesen, Claus; Brazhe, Alexey; Thomsen, Kirsten; Lauritzen, Martin

    2012-01-01

    Glial calcium (Ca2+) waves constitute a means to spread signals between glial cells and to neighboring neurons and blood vessels. These waves occur spontaneously in Bergmann glia (BG) of the mouse cerebellar cortex in vivo. Here, we tested three hypotheses: (1) aging and reduced blood oxygen saturation alters wave activity; (2) glial Ca2+ waves change cerebral oxygen metabolism; and (3) neuronal and glial wave activity is correlated. We used two-photon microscopy in the cerebellar cortexes of...

  19. Heart tissue of harlequin (hq)/Big Blue mice has elevated reactive oxygen species without significant impact on the frequency and nature of point mutations in nuclear DNA

    Energy Technology Data Exchange (ETDEWEB)

    Crabbe, Rory A. [Department of Biology, University of Western Ontario, London, Ontario, N6A 5B7 (Canada); Hill, Kathleen A., E-mail: khill22@uwo.ca [Department of Biology, University of Western Ontario, London, Ontario, N6A 5B7 (Canada)

    2010-09-10

    Age is a major risk factor for heart disease, and cardiac aging is characterized by elevated mitochondrial reactive oxygen species (ROS) with compromised mitochondrial and nuclear DNA integrity. To assess links between increased ROS levels and mutations, we examined in situ levels of ROS and cII mutation frequency, pattern and spectrum in the heart of harlequin (hq)/Big Blue mice. The hq mouse is a model of premature aging with mitochondrial dysfunction and increased risk of oxidative stress-induced heart disease with the means for in vivo mutation detection. The hq mutation produces a significant downregulation in the X-linked apoptosis-inducing factor gene (Aif) impairing both the antioxidant and oxidative phosphorylation functions of AIF. Brain and skin of hq disease mice have elevated frequencies of point mutations in nuclear DNA and histopathology characterized by cell loss. Reports of associated elevations in ROS in brain and skin have mixed results. Herein, heart in situ ROS levels were elevated in hq disease compared to AIF-proficient mice (p < 0.0001) yet, mutation frequency and pattern were similar in hq disease, hq carrier and AIF-proficient mice. Heart cII mutations were also assessed 15 days following an acute exposure to an exogenous ROS inducer (10 mg paraquat/kg). Acute paraquat exposure with a short mutant manifestation period was insufficient to elevate mutation frequency or alter mutation pattern in the post-mitotic heart tissue of AIF-proficient mice. Paraquat induction of ROS requires mitochondrial complex I and thus is likely compromised in hq mice. Results of this preliminary survey and the context of recent literature suggest that determining causal links between AIF deficiency and the premature aging phenotypes of specific tissues is better addressed with assay of mitochondrial ROS and large-scale changes in mitochondrial DNA in specific cell types.

  20. Hypoxic-Ischemic Injury in the Developing Brain: The Role of Reactive Oxygen Species Originating in Mitochondria

    OpenAIRE

    Ten, Vadim S.; Anatoly Starkov

    2012-01-01

    Mitochondrial dysfunction is the most fundamental mechanism of cell damage in cerebral hypoxia-ischemia and reperfusion. Mitochondrial respiratory chain (MRC) is increasingly recognized as a source for reactive oxygen species (ROS) in the postischemic tissue. Potentially, ROS originating in MRC can contribute to the reperfusion-driven oxidative stress, promoting mitochondrial membrane permeabilization. The loss of mitochondrial membranes integrity during reperfusion is considered as the major...

  1. An upgraded camera-based imaging system for mapping venous blood oxygenation in human skin tissue

    Science.gov (United States)

    Li, Jun; Zhang, Xiao; Qiu, Lina; Leotta, Daniel F.

    2016-07-01

    A camera-based imaging system was previously developed for mapping venous blood oxygenation in human skin. However, several limitations were realized in later applications, which could lead to either significant bias in the estimated oxygen saturation value or poor spatial resolution in the map of the oxygen saturation. To overcome these issues, an upgraded system was developed using improved modeling and image processing algorithms. In the modeling, Monte Carlo (MC) simulation was used to verify the effectiveness of the ratio-to-ratio method for semi-infinite and two-layer skin models, and then the relationship between the venous oxygen saturation and the ratio-to-ratio was determined. The improved image processing algorithms included surface curvature correction and motion compensation. The curvature correction is necessary when the imaged skin surface is uneven. The motion compensation is critical for the imaging system because surface motion is inevitable when the venous volume alteration is induced by cuff inflation. In addition to the modeling and image processing algorithms in the upgraded system, a ring light guide was used to achieve perpendicular and uniform incidence of light. Cross-polarization detection was also adopted to suppress surface specular reflection. The upgraded system was applied to mapping of venous oxygen saturation in the palm, opisthenar and forearm of human subjects. The spatial resolution of the oxygenation map achieved is much better than that of the original system. In addition, the mean values of the venous oxygen saturation for the three locations were verified with a commercial near-infrared spectroscopy system and were consistent with previously published data.

  2. Nuclear microprobe analysis of the selective boron uptake obtained with BPA in brain tumour tissue

    Science.gov (United States)

    Wegdén, M.; Kristiansson, P.; Ceberg, C.; Munck af Rosenschöld, P.; Auzelyte, V.; Elfman, M.; Malmqvist, K. G.; Nilsson, C.; Pallon, J.; Shariff, A.

    2004-06-01

    The tumour selective ability of the boron compound boronophenylalanine (BPA), today used in Boron Neutron Capture Therapy in Sweden, has been investigated with the Lund Nuclear Microprobe. The tumour to tissue ratio of the boron concentration, as well as the location of boron within the cells, is critical for the efficiency of the therapy. It is desirable that the boron is accumulated as close as possible to the cell nucleus, since the alpha particles produced in the 10B(n,α) 7Li reaction only have a range of about 10 microns, i.e. a cell diameter. The nuclear reaction 11B(p,α)2α, which has an especially high cross-section (300 mb) for 660 keV protons, has been used to analyse brain tissue from BPA-injected rats. Previous studies on other boron compounds have shown significant background problems when the alpha particles are detected in the backward direction. By a specially designed set-up, alpha particles in the forward and backward direction are detected simultaneously, and only the coincidences between the two directions are considered to be true boron events. In this way we could achieve excellent background suppression. The analysis shows that BPA indeed is tumour selective. Quantifications show a boron abundance of 150 ± 20 ng/cm 2 in normal tissue and 567 ± 70 ng/cm 2 in tumour tissue. If the rat is fed with L-dopa before the injection of BPA the uptake increases 3-4 times. The boron is homogeneously distributed in the cellular structure and no specific intracellular accumulation has been shown.

  3. Nuclear microprobe analysis of the selective boron uptake obtained with BPA in brain tumour tissue

    Energy Technology Data Exchange (ETDEWEB)

    Wegden, M. E-mail: marie.wegden@nuclear.lu.se; Kristiansson, P.; Ceberg, C.; Munck af Rosenschoeld, P.; Auzelyte, V.; Elfman, M.; Malmqvist, K.G.; Nilsson, C.; Pallon, J.; Shariff, A

    2004-06-01

    The tumour selective ability of the boron compound boronophenylalanine (BPA), today used in Boron Neutron Capture Therapy in Sweden, has been investigated with the Lund Nuclear Microprobe. The tumour to tissue ratio of the boron concentration, as well as the location of boron within the cells, is critical for the efficiency of the therapy. It is desirable that the boron is accumulated as close as possible to the cell nucleus, since the alpha particles produced in the {sup 10}B(n,{alpha}){sup 7}Li reaction only have a range of about 10 microns, i.e. a cell diameter. The nuclear reaction {sup 11}B(p,{alpha})2{alpha}, which has an especially high cross-section (300 mb) for 660 keV protons, has been used to analyse brain tissue from BPA-injected rats. Previous studies on other boron compounds have shown significant background problems when the alpha particles are detected in the backward direction. By a specially designed set-up, alpha particles in the forward and backward direction are detected simultaneously, and only the coincidences between the two directions are considered to be true boron events. In this way we could achieve excellent background suppression. The analysis shows that BPA indeed is tumour selective. Quantifications show a boron abundance of 150 {+-} 20 ng/cm{sup 2} in normal tissue and 567 {+-} 70 ng/cm{sup 2} in tumour tissue. If the rat is fed with L-dopa before the injection of BPA the uptake increases 3-4 times. The boron is homogeneously distributed in the cellular structure and no specific intracellular accumulation has been shown.

  4. Real time analysis of brain tissue by direct combination of ultrasonic surgical aspiration and sonic spray mass spectrometry.

    Science.gov (United States)

    Schäfer, Karl-Christian; Balog, Júlia; Szaniszló, Tamás; Szalay, Dániel; Mezey, Géza; Dénes, Júlia; Bognár, László; Oertel, Matthias; Takáts, Zoltán

    2011-10-15

    Direct combination of cavitron ultrasonic surgical aspirator (CUSA) and sonic spray ionization mass spectrometry is presented. A commercially available ultrasonic surgical device was coupled to a Venturi easy ambient sonic-spray ionization (V-EASI) source by directly introducing liquified tissue debris into the Venturi air jet pump. The Venturi air jet pump was found to efficiently nebulize the suspended tissue material for gas phase ion production. The ionization mechanism involving solely pneumatic spraying was associated with that of sonic spray ionization. Positive and negative ionization spectra were obtained from brain and liver samples reflecting the primary application areas of the surgical device. Mass spectra were found to feature predominantly complex lipid-type constituents of tissues in both ion polarity modes. Multiply charged peptide anions were also detected. The influence of instrumental settings was characterized in detail. Venturi pump geometry and flow parameters were found to be critically important in ionization efficiency. Standard solutions of phospholipids and peptides were analyzed in order to test the dynamic range, sensitivity, and suppression effects. The spectra of the intact tissue specimens were found to be highly specific to the histological tissue type. The principal component analysis (PCA) and linear discriminant analysis (LDA) based data analysis method was developed for real-time tissue identification in a surgical environment. The method has been successfully tested on post-mortem and ex vivo human samples including astrocytomas, meningeomas, metastatic brain tumors, and healthy brain tissue.

  5. The large shear strain dynamic behaviour of in-vitro porcine brain tissue and a silicone gel model material.

    Science.gov (United States)

    Brands, D W; Bovendeerd, P H; Peters, G W; Wismans, J S

    2000-11-01

    The large strain dynamic behaviour of brain tissue and silicone gel, a brain substitute material used in mechanical head models, was compared. The non-linear shear strain behaviour was characterised using stress relaxation experiments. Brain tissue showed significant shear softening for strains above 1% (approximately 30% softening for shear strains up to 20%) while the time relaxation behaviour was nearly strain independent. Silicone gel behaved as a linear viscoelastic solid for all strains tested (up to 50%) and frequencies up to 461 Hz. As a result, the large strain time dependent behaviour of both materials could be derived for frequencies up to 1000 Hz from small strain oscillatory experiments and application of Time Temperature Superpositioning. It was concluded that silicone gel material parameters are in the same range as those of brain tissue. Nevertheless the brain tissue response will not be captured exactly due to increased viscous damping at high frequencies and the absence of shear softening in the silicone gel. For trend studies and benchmarking of numerical models the gel can be a good model material.

  6. Imaging MALDI MS of Dosed Brain Tissues Utilizing an Alternative Analyte Pre-extraction Approach

    Science.gov (United States)

    Quiason, Cristine M.; Shahidi-Latham, Sheerin K.

    2015-06-01

    Matrix-assisted laser desorption ionization (MALDI) imaging mass spectrometry has been adopted in the pharmaceutical industry as a useful tool to detect xenobiotic distribution within tissues. A unique sample preparation approach for MALDI imaging has been described here for the extraction and detection of cobimetinib and clozapine, which were previously undetectable in mouse and rat brain using a single matrix application step. Employing a combination of a buffer wash and a cyclohexane pre-extraction step prior to standard matrix application, the xenobiotics were successfully extracted and detected with an 8 to 20-fold gain in sensitivity. This alternative approach for sample preparation could serve as an advantageous option when encountering difficult to detect analytes.

  7. Novel Discrete Compactness-Based Training for Vector Quantization Networks: Enhancing Automatic Brain Tissue Classification

    Directory of Open Access Journals (Sweden)

    Ricardo Pérez-Aguila

    2013-01-01

    Full Text Available An approach for nonsupervised segmentation of Computed Tomography (CT brain slices which is based on the use of Vector Quantization Networks (VQNs is described. Images are segmented via a VQN in such way that tissue is characterized according to its geometrical and topological neighborhood. The main contribution rises from the proposal of a similarity metric which is based on the application of Discrete Compactness (DC which is a factor that provides information about the shape of an object. One of its main strengths lies in the sense of its low sensitivity to variations, due to noise or capture defects, in the shape of an object. We will present, compare, and discuss some examples of segmentation networks trained under Kohonen’s original algorithm and also under our similarity metric. Some experiments are established in order to measure the effectiveness and robustness, under our application of interest, of the proposed networks and similarity metric.

  8. Radiosensitisation in normal tissues with oxygen, carbogen or nicotinamide: therapeutic gain comparisons for fractionated x-ray schedules

    International Nuclear Information System (INIS)

    Methods: Radiosensitisation with oxygen, carbogen or nicotinamide alone and oxygen or carbogen combined with nicotinamide was compared in early and late responding normal tissues in rodents. X-ray treatments were delivered as single doses or fractionated schedules of 2 fractions in 1 day, 2, 12 and 36 fractions in an overall time of 12 days and 10 fractions in 5 or 12 days. Acute skin reactions, survival of intestinal crypts, breathing rate, reduction in the packed red-cell volume and clearance of 51Cr-EDTA were used as assays of epidermal, gut, lung and renal damage. Results: Relative to air-breathing mice, carbogen or oxygen produced a small, and not always significant, increase in sensitivity (enhancement ratios ≤ 1.15) in gut, lung and kidneys; however, in skin a dose enhancement of 1.2-1.3 was observed. The effect of nicotinamide in air, carbogen or oxygen was studied only in lung and gut. The drug produced variable but generally significant increases in radiosensitisation (≤ 1.26) in all three gases. Relative to treatments in air, enhancement ratios for nicotinamide alone were usually slightly higher than those observed when either carbogen or oxygen were administered without the drug. With all three modifiers (i.e. oxygen, carbogen, nicotinamide alone or for the drug-gas combinations) there was no significant change in the enhancement ratios observed as the number of radiation dose fractions was varied. Conclusions: Comparisons with fractionated X-ray studies done previously in rodent tumours indicate that a therapeutic benefit, relative to lung, gut and renal damage, would be observed with oxygen or carbogen alone but not with nicotinamide alone. The greatest gain would be achieved with the combination of carbogen and nicotinamide, with which a benefit was observed even relative to epidermal damage. These results indicate that some decrease in normal tissue tolerance could be observed when using these modifiers in clinical radiotherapy and, although

  9. Craniofacial tissue oxygen saturation is associated with blood pH using an examiner's finger-mounted tissue oximetry in mice

    Science.gov (United States)

    Uchida, Toshiyuki; Kanayama, Naohiro; Kawai, Kenta; Niwayama, Masatsugu

    2016-04-01

    Although fetal scalp blood sampling is an examination to assess fetal acidosis during the intrapartum period, it has not been widely used by obstetricians because of its invasiveness. We have developed a small, portable oximetry with a sensor attached to the examiner's finger. Our previous report using this oximetry concluded that fetal head tissue oxygen saturation (StO2) correlated with umbilical cord artery blood pH. We investigated whether the association between StO2 and blood pH in mice could be validated using this oximetry. Eleven the Institute for Cancer Research (ICR) mice were measured using a near-infrared spectroscopy probe at the craniofacial site in a closed polyethylene bag while changing the oxygen concentration. A total of nine blood samples were collected and analyzed for pH. The StO2 and tissue blood pH showed a strong positive correlation (r=0.90 and P=0.0009). The StO2 and total hemoglobin index also showed a positive correlation (r=0.84 and P=0.0049). Thus, the results of the present study support those of our previous report on clinical cases and allow examiners to easily check the status of fetal acidosis. Fetal management using this oximetry might gain popularity with obstetricians in the near future.

  10. Influences of brain tissue poroelastic constants on intracranial pressure (ICP) during constant-rate infusion.

    Science.gov (United States)

    Li, Xiaogai; von Holst, Hans; Kleiven, Svein

    2013-01-01

    A 3D finite element (FE) model has been developed to study the mean intracranial pressure (ICP) response during constant-rate infusion using linear poroelasticity. Due to the uncertainties in the poroelastic constants for brain tissue, the influence of each of the main parameters on the transient ICP infusion curve was studied. As a prerequisite for transient analysis, steady-state simulations were performed first. The simulated steady-state pressure distribution in the brain tissue for a normal cerebrospinal fluid (CSF) circulation system showed good correlation with experiments from the literature. Furthermore, steady-state ICP closely followed the infusion experiments at different infusion rates. The verified steady-state models then served as a baseline for the subsequent transient models. For transient analysis, the simulated ICP shows a similar tendency to that found in the experiments, however, different values of the poroelastic constants have a significant effect on the infusion curve. The influence of the main poroelastic parameters including the Biot coefficient α, Skempton coefficient B, drained Young's modulus E, Poisson's ratio ν, permeability κ, CSF absorption conductance C(b) and external venous pressure p(b) was studied to investigate the influence on the pressure response. It was found that the value of the specific storage term S(ε) is the dominant factor that influences the infusion curve, and the drained Young's modulus E was identified as the dominant parameter second to S(ε). Based on the simulated infusion curves from the FE model, artificial neural network (ANN) was used to find an optimised parameter set that best fit the experimental curve. The infusion curves from both the FE simulation and using ANN confirmed the limitation of linear poroelasticity in modelling the transient constant-rate infusion. PMID:22452461

  11. Investigating the recovery period of rat brain tissue after electrolytic and 980-nm laser induced lesions

    Science.gov (United States)

    Bozkulak, Ozguncem; Tabakoglu, H. Ozgur; Aksoy, Ayla; Canbeyli, Resit; Bilgin, Nes'e.; Kurtkaya, Ozlem; Sav, Aydin; Gulsoy, Murat

    2003-10-01

    The effects of 980-nm diode laser and electrolytic lesions in Wistar rat brain tissue were observed by immunohistochemical staining for CD68 marker and Hematoxylin-Eosin (H&E). Bilateral lesions; laser lesions (2W/2sec) in the right hemispheres, and electrolytic lesions (1.5mA/20sec) in the left hemispheres were done through in vivo stereotaxic neurosurgical procedure. Subjects were classified into three groups due to the recovery period. Subjects in Group I, II, and III were sacrificed after 0, 2 and 7 days of recovery period respectively. After saline perfusion their brains were dislocated, and paraffin embedded sections were taken. One section for H&E and one for CD68 were cut consecutively in 3μm thickness by examining the lesion in every 30-μm thickness. CD68 was found more efficient marker than H&E in observing the after-effects of both types of lesions. The total damage of laser was smaller than that of electrosurgical unit. The shape of the ablated area in laser induced lesions was more spherical than that of electrosurgical unit. The number of macrophages increased as the recovery period increased for all subjects. Group III showed the highest number of macrophages in three, and the number of macrophages around electrolytic lesion is nearly 1.5 times higher than that of laser lesion. The remarkable ablating ability, the damage zone created and the healing of nearby tissue clearly showed that the 980-nm diode laser is an effective and useful alternative to electrosurgical unit in neurosurgery.

  12. Brain

    Science.gov (United States)

    ... will return after updating. Resources Archived Modules Updates Brain Cerebrum The cerebrum is the part of the ... the outside of the brain and spinal cord. Brain Stem The brain stem is the part of ...

  13. Assessing Antioxidant Capacity in Brain Tissue: Methodologies and Limitations in Neuroprotective Strategies.

    Science.gov (United States)

    Slemmer, Jennifer E; Weber, John T

    2014-01-01

    The number of putative neuroprotective compounds with antioxidant activity described in the literature continues to grow. Although these compounds are validated using a variety of in vivo and in vitro techniques, they are often evaluated initially using in vitro cell culture techniques in order to establish toxicity and effective concentrations. Both in vivo and in vitro methodologies have their respective advantages and disadvantages, including, but not limited to, cost, time, use of resources and technical limitations. This review expands on the inherent benefits and drawbacks of in vitro and in vivo methods for assessing neuroprotection, especially in light of proper evaluation of compound efficacy and neural bioavailability. For example, in vivo studies can better evaluate the effects of protective compounds and/or its metabolites on various tissues, including the brain, in the whole animal, whereas in vitro studies can better discern the cellular and/or mechanistic effects of compounds. In particular, we aim to address the question of appropriate and accurate extrapolation of findings from in vitro experiment-where compounds are often directly applied to cellular extracts, potentially at higher concentrations than would ever cross the blood-brain barrier-to the more complex scenario of neuroprotection due to pharmacodynamics in vivo. PMID:26785231

  14. Assessing Antioxidant Capacity in Brain Tissue: Methodologies and Limitations in Neuroprotective Strategies

    Directory of Open Access Journals (Sweden)

    Jennifer E. Slemmer

    2014-10-01

    Full Text Available The number of putative neuroprotective compounds with antioxidant activity described in the literature continues to grow. Although these compounds are validated using a variety of in vivo and in vitro techniques, they are often evaluated initially using in vitro cell culture techniques in order to establish toxicity and effective concentrations. Both in vivo and in vitro methodologies have their respective advantages and disadvantages, including, but not limited to, cost, time, use of resources and technical limitations. This review expands on the inherent benefits and drawbacks of in vitro and in vivo methods for assessing neuroprotection, especially in light of proper evaluation of compound efficacy and neural bioavailability. For example, in vivo studies can better evaluate the effects of protective compounds and/or its metabolites on various tissues, including the brain, in the whole animal, whereas in vitro studies can better discern the cellular and/or mechanistic effects of compounds. In particular, we aim to address the question of appropriate and accurate extrapolation of findings from in vitro experiment-where compounds are often directly applied to cellular extracts, potentially at higher concentrations than would ever cross the blood-brain barrier—to the more complex scenario of neuroprotection due to pharmacodynamics in vivo.

  15. Experimental and numerical evaluation of drug release from nanofiber mats to brain tissue.

    Science.gov (United States)

    Nakielski, Paweł; Kowalczyk, Tomasz; Zembrzycki, Krzysztof; Kowalewski, Tomasz A

    2015-02-01

    Drug delivery systems based on nanofibrous mats appear to be a promising healing practice for preventing brain neurodegeneration after surgery. One of the problems encountered during planning and constructing optimal delivery system based on nanofibrous mats is the estimation of parameters crucial for predicting drug release dynamics. This study describes our experimental setup allowing for spatial and temporary evaluation of drug release from nanofibrous polymers to obtain data necessary to validate appropriate numerical models. We applied laser light sheet method to illuminate released fluorescent drug analog and CCD camera for imaging selected cross-section of the investigated volume. Transparent hydrogel was used as a brain tissue phantom. The proposed setup allows for continuous observation of drug analog (fluorescent dye) diffusion for time span of several weeks. Images captured at selected time intervals were processed to determine concentration profiles and drug release kinetics. We used presented method to evaluate drug release from several polymers to validate numerical model used for optimizing nanofiber system for neuroprotective dressing.

  16. Quantitative analysis of phenibut in rat brain tissue extracts by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Grinberga, Solveiga; Zvejniece, Liga; Liepinsh, Edgars; Dambrova, Maija; Pugovics, Osvalds

    2008-12-01

    Phenibut (3-phenyl-4-aminobutyric acid) is a gamma-aminobutyric acid mimetic drug, which is used clinically as a mood elevator and tranquilizer. In the present work, a rapid, selective and sensitive liquid chromatography-tandem mass spectrometry method for quantification of phenibut in biological matrices has been developed. The method is based on protein precipitation with acidic acetonitrile followed by isocratic chromatographic separation using acetonitrile-formic acid (0.1% in water; 8:92, v/v) mobile phase on a reversed-phase column. Detection of the analyte was performed by electrospray ionization mass spectrometry in multiple reaction monitoring mode with the precursor-to-product ion transition m/z 180.3 --> m/z 117.2. The calibration curve was linear over the concentration range 50-2000 ng/mL. The lower limit of quantification for phenibut in rat brain extracts was 50 ng/mL. Acceptable precision and accuracy were obtained over the whole concentration range. The validated method was successfully applied in a pharmacological study to analyze phenibut concentration in rat brain tissue extract samples. PMID:19034959

  17. Muscle tissue oxygenation, pressure, electrical, and mechanical responses during dynamic and static voluntary contractions

    DEFF Research Database (Denmark)

    Vedsted, Pernille; Blangsted, Anne Katrine; Søgaard, Karen;

    2006-01-01

    Dynamic muscle contractions have been shown to cause greater energy turnover and fatigue than static contractions performed at a corresponding force level. Therefore, we hypothesized that: (1) electro- (EMG) and mechanomyography (MMG), intramuscular pressure (IMP), and reduction in muscle oxygen...... tension (rTO(2)) would be larger during dynamic (DYN) than intermittent static (IST) low force contractions; and that (2) oxygen tension would remain lower in the resting periods subsequent to DYN as compared to those following IST. Eight subjects performed elbow flexions with identical time...

  18. Analysis of RNA from Alzheimer's Disease Post-mortem Brain Tissues.

    Science.gov (United States)

    Clement, Christian; Hill, James M; Dua, Prerna; Culicchia, Frank; Lukiw, Walter J

    2016-03-01

    Alzheimer's disease (AD) is a uniquely human, age-related central nervous system (CNS) disorder for which there is no adequate experimental model. While well over 100 transgenic murine models of AD (TgAD) have been developed that recapitulate many of the neuropathological features of AD, key pathological features of AD such as progressive neuronal atrophy, neuron cell loss, and neurofibrillary tangle (NFT) formation have not been observed in any TgAD model to date. To more completely analyze and understand the neuropathology, altered neuro-inflammatory and innate-immune signaling pathways, and the complex molecular-genetics and epigenetics of AD, it is therefore necessary to rigorously examine short post-mortem interval (PMI) human brain tissues to gain a deeper and more thorough insight into the neuropathological mechanisms that characterize the AD process. This perspective-methods paper will highlight some important recent findings on the utilization of short PMI tissues in sporadic (idiopathic; of unknown origin) AD research with focus on the extraction and quantification of RNA, and in particular microRNA (miRNA) and messenger RNA (mRNA) and analytical strategies, drawing on the authors' combined 125 years of laboratory experience into this investigative research area. We sincerely hope that new investigators in the field of "gene expression analysis in neurological disease" will benefit from the observations presented here and incorporate these recent findings and observations into their future experimental planning and design. PMID:25631714

  19. An atlas-based fuzzy connectedness method for automatic tissue classification in brain MRI

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yongxin; BAI Jing

    2006-01-01

    A framework incorporating a subject-registered atlas into the fuzzy connectedness (FC) method is proposed for the automatic tissue classification of 3D images of brain MRI. The pre-labeled atlas is first registered onto the subject to provide an initial approximate segmentation. The initial segmentation is used to estimate the intensity histograms of gray matter and white matter. Based on the estimated intensity histograms, multiple seed voxels are assigned to each tissue automatically. The normalized intensity histograms are utilized in the FC method as the intensity probability density function (PDF) directly. Relative fuzzy connectedness technique is adopted in the final classification of gray matter and white matter. Experimental results based on the 20 data sets from IBSR are included, as well as comparisons of the performance of our method with that of other published methods. This method is fully automatic and operator-independent. Therefore, it is expected to find wide applications, such as 3D visualization, radiation therapy planning, and medical database construction.

  20. What lies beneath? Diffusion EAP-based study of brain tissue microstructure.

    Science.gov (United States)

    Zucchelli, Mauro; Brusini, Lorenza; Andrés Méndez, C; Daducci, Alessandro; Granziera, Cristina; Menegaz, Gloria

    2016-08-01

    Diffusion weighted magnetic resonance signals convey information about tissue microstructure and cytoarchitecture. In the last years, many models have been proposed for recovering the diffusion signal and extracting information to constitute new families of numerical indices. Two main categories of reconstruction models can be identified in diffusion magnetic resonance imaging (DMRI): ensemble average propagator (EAP) models and compartmental models. From both, descriptors can be derived for elucidating the underlying microstructural architecture. While compartmental models indices directly quantify the fraction of different cell compartments in each voxel, EAP-derived indices are only a derivative measure and the effect of the different microstructural configurations on the indices is still unclear. In this paper, we analyze three EAP indices calculated using the 3D Simple Harmonic Oscillator based Reconstruction and Estimation (3D-SHORE) model and estimate their changes with respect to the principal microstructural configurations. We take advantage of the state of the art simulations to quantify the variations of the indices with the simulation parameters. Analysis of in-vivo data correlates the EAP indices with the microstructural parameters obtained from the Neurite Orientation Dispersion and Density Imaging (NODDI) model as a pseudo ground truth for brain data. Results show that the EAP derived indices convey information on the tissue microstructure and that their combined values directly reflect the configuration of the different compartments in each voxel.

  1. Quantitative comparison of preparation methodologies for X-ray fluorescence microscopy of brain tissue

    International Nuclear Information System (INIS)

    X-ray fluorescence microscopy (XFM) facilitates high-sensitivity quantitative imaging of trace metals at high spatial resolution over large sample areas and can be applied to a diverse range of biological samples. Accurate determination of elemental content from recorded spectra requires proper calibration of the XFM instrument under the relevant operating conditions. Here, we describe the manufacture, characterization, and utilization of multi-element thin-film reference foils for use in calibration of XFM measurements of biological and other specimens. We have used these internal standards to assess the two-dimensional distribution of trace metals in a thin tissue section of a rat hippocampus. The data used in this study was acquired at the XFM beamline of the Australian Synchrotron using a new 384-element array detector (Maia) and at beamline 2-ID-E at the Advanced Photon Source. Post-processing of samples by different fixation techniques was investigated, with the conclusion that differences in solvent type and sample handling can significantly alter elemental content. The present study highlights the quantitative capability, high statistical power, and versatility of the XFM technique for mapping trace metals in biological samples, e.g., brain tissue samples in order to help understand neurological processes, especially when implemented in conjunction with a high-performance detector such as Maia. (orig.)

  2. Sources of Technical Variability in Quantitative LC-MS Proteomics: Human Brain Tissue Sample Analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Piehowski, Paul D.; Petyuk, Vladislav A.; Orton, Daniel J.; Xie, Fang; Moore, Ronald J.; Ramirez Restrepo, Manuel; Engel, Anzhelika; Lieberman, Andrew P.; Albin, Roger L.; Camp, David G.; Smith, Richard D.; Myers, Amanda J.

    2013-05-03

    To design a robust quantitative proteomics study, an understanding of both the inherent heterogeneity of the biological samples being studied as well as the technical variability of the proteomics methods and platform is needed. Additionally, accurately identifying the technical steps associated with the largest variability would provide valuable information for the improvement and design of future processing pipelines. We present an experimental strategy that allows for a detailed examination of the variability of the quantitative LC-MS proteomics measurements. By replicating analyses at different stages of processing, various technical components can be estimated and their individual contribution to technical variability can be dissected. This design can be easily adapted to other quantitative proteomics pipelines. Herein, we applied this methodology to our label-free workflow for the processing of human brain tissue. For this application, the pipeline was divided into four critical components: Tissue dissection and homogenization (extraction), protein denaturation followed by trypsin digestion and SPE clean-up (digestion), short-term run-to-run instrumental response fluctuation (instrumental variance), and long-term drift of the quantitative response of the LC-MS/MS platform over the 2 week period of continuous analysis (instrumental stability). From this analysis, we found the following contributions to variability: extraction (72%) >> instrumental variance (16%) > instrumental stability (8.4%) > digestion (3.1%). Furthermore, the stability of the platform and its’ suitability for discovery proteomics studies is demonstrated.

  3. Quantitative comparison of preparation methodologies for X-ray fluorescence microscopy of brain tissue

    Energy Technology Data Exchange (ETDEWEB)

    James, Simon A.; Sexton, Brett A.; Hoobin, Pamela; Mayo, Sheridan C. [CSIRO, Materials Science and Engineering and the Preventative Health Flagship, Clayton, VIC (Australia); Myers, Damian E. [St. Vincent s Hospital, Department of Surgery/Orthopaedics, Fitzroy, VIC (Australia); University of Melbourne, Department of Surgery, Parkville, VIC (Australia); Jonge, Martin D. de; Paterson, David; Howard, Daryl L. [Australian Synchrotron, Clayton, VIC (Australia); Vogt, Stefan [Argonne National Laboratory, X-ray Science Division, Argonne, IL (United States); Ryan, Chris G. [CSIRO, Earth Science and Resources Engineering, Clayton, VIC (Australia); University of Melbourne, School of Physics, Parkville, VIC (Australia); University of Tasmania, CODES Centre of Excellence, Hobart, TAS (Australia); Altissimo, Matteo [Melbourne Centre for Nanofabrication, Clayton, VIC (Australia); Moorhead, Gareth F. [CSIRO, Materials Science and Engineering and the Preventative Health Flagship, Clayton, VIC (Australia); University of Melbourne, School of Physics, Parkville, VIC (Australia); Wilkins, Stephen W. [CSIRO, Materials Science and Engineering and the Preventative Health Flagship, Clayton, VIC (Australia); Monash University, School of Physics, Clayton, VIC (Australia)

    2011-08-15

    X-ray fluorescence microscopy (XFM) facilitates high-sensitivity quantitative imaging of trace metals at high spatial resolution over large sample areas and can be applied to a diverse range of biological samples. Accurate determination of elemental content from recorded spectra requires proper calibration of the XFM instrument under the relevant operating conditions. Here, we describe the manufacture, characterization, and utilization of multi-element thin-film reference foils for use in calibration of XFM measurements of biological and other specimens. We have used these internal standards to assess the two-dimensional distribution of trace metals in a thin tissue section of a rat hippocampus. The data used in this study was acquired at the XFM beamline of the Australian Synchrotron using a new 384-element array detector (Maia) and at beamline 2-ID-E at the Advanced Photon Source. Post-processing of samples by different fixation techniques was investigated, with the conclusion that differences in solvent type and sample handling can significantly alter elemental content. The present study highlights the quantitative capability, high statistical power, and versatility of the XFM technique for mapping trace metals in biological samples, e.g., brain tissue samples in order to help understand neurological processes, especially when implemented in conjunction with a high-performance detector such as Maia. (orig.)

  4. The relationship between decorrelation time and sample thickness in acute rat brain tissue slices (Conference Presentation)

    Science.gov (United States)

    Brake, Joshua; Jang, Mooseok; Yang, Changhuei

    2016-03-01

    The optical opacity of biological tissue has long been a challenge in biomedical optics due to the strong scattering nature of tissue in the optical regime. While most conventional optical techniques attempt to gate out multiply scattered light and use only unscattered light, new approaches in the field of wavefront shaping exploit the time reversible symmetry of optical scattering in order to focus light inside or through scattering media. While these approaches have been demonstrated effectively on static samples, it has proven difficult to apply them to dynamic biological samples since even small changes in the relative positions of the scatterers within will cause the time symmetry that wavefront shaping relies upon to decorrelate. In this paper we investigate the decorrelation curves of acute rat brain slices for thicknesses in the range 1-3 mm (1/e decorrelation time on the order of seconds) using multi-speckle diffusing wave spectroscopy (MSDWS) and compare the results with theoretical predictions. The results of this study demonstrate that the 1/L^2 relationship between decorrelation time and thickness predicted by diffusing wave spectroscopy provides a good rule of thumb for estimating how the decorrelation of a sample will change with increasing thickness. Understanding this relationship will provide insight to guide the future development of biophotonic wavefront shaping tools by giving an estimate of how fast wavefront shaping systems need to operate to overcome the dynamic nature of biological samples.

  5. In situ monitoring of brain tissue reaction of chronically implanted electrodes with an optical coherence tomography fiber system

    Science.gov (United States)

    Xie, Yijing; Hassler, Christina; Stieglitz, Thomas; Seifert, Andreas; Hofmann, Ulrich G.

    2014-03-01

    Neural microelectrodes are well established tools for delivering therapeutic electrical pulses, and recording neural electrophysiological signals. However, long term implanted neural probes often become functionally impaired by tissue encapsulation. At present, analyzing this immune reaction is only feasible with post-mortem histology; currently no means for specific in vivo monitoring exist and most applicable imaging modalities provide no sufficient resolution for a cellular measurement in deep brain regions. Optical coherence tomography (OCT) is a well developed imaging modality, providing cellular resolution and up to 1.2 mm imaging depth in brain tissue. Further more, a fiber based spectral domain OCT was shown to be capable of minimally invasive brain intervention. In the present study, we propose to use a fiber based spectral domain OCT to monitor the the progression of the tissue's immune response and scar encapsulation of microprobes in a rat animal model. We developed an integrated OCT fiber catheter consisting of an implantable ferrule based fiber cannula and a fiber patch cable. The fiber cannula was 18.5 mm long, including a 10.5 mm ceramic ferrule and a 8.0 mm long, 125 μm single mode fiber. A mating sleeve was used to fix and connect the fiber cannula to the OCT fiber cable. Light attenuation between the OCT fiber cable and the fiber cannula through the mating sleeve was measured and minimized. The fiber cannula was implanted in rat brain together with a microelectrode in sight used as a foreign body to induce the brain tissue immune reaction. Preliminary data showed a significant enhancement of the OCT backscattering signal during the brain tissue scarring process, while the OCT signal of the flexible microelectrode was getting weaker consequentially.

  6. Precision of measurement of cerebral tissue oxygenation index using near-infrared spectroscopy in preterm neonates

    DEFF Research Database (Denmark)

    Sorensen, Line C; Greisen, Gorm

    2006-01-01

    the optode several times presuming no regional differences in cerebral oxygenation. Thirty-seven premature infants were examined with several measurements of c-TOI using the NIRO 300 oximeter. Three to eight measurements were done on each infant over a period of 15 to 25 min. One-way analysis of variance...

  7. Spontaneous calcium waves in Bergman glia increase with age and hypoxia and may reduce tissue oxygen

    DEFF Research Database (Denmark)

    Mathiesen, Claus; Brazhe, Alexey; Thomsen, Kirsten Joan;

    2013-01-01

    Glial calcium (Ca(2+)) waves constitute a means to spread signals between glial cells and to neighboring neurons and blood vessels. These waves occur spontaneously in Bergmann glia (BG) of the mouse cerebellar cortex in vivo. Here, we tested three hypotheses: (1) aging and reduced blood oxygen sa...

  8. Oxygen-glucose deprivation increases the enzymatic activity and the microvesicle-mediated release of ectonucleotidases in the cells composing the blood-brain barrier.

    Science.gov (United States)

    Ceruti, Stefania; Colombo, Laura; Magni, Giulia; Viganò, Francesca; Boccazzi, Marta; Deli, Mária A; Sperlágh, Beáta; Abbracchio, Maria P; Kittel, Agnes

    2011-08-01

    The blood-brain barrier (BBB), the dynamic interface between the nervous tissue and the blood, is composed by endothelial cells, pericytes and astrocytes. Extracellular nucleotides and nucleosides and their receptors (the purinergic system) constitute a widely diffused signaling system involved in many pathophysiological processes. However, the role of this system in controlling BBB functions is still largely unknown. By using cultures of these three cell types grown separately and a BBB in vitro model consisting of triple co-cultures, we studied for the first time the expression and distribution of the ecto-enzymes nucleoside triphosphate diphosphohydrolases (NTPDases, the enzymes which hydrolyze extracellular nucleotides) under control and ischemic (oxygen-glucose deprivation in vitro; OGD) conditions. NTPDase1 was detected in all three cell types, whereas NTPDase2 was expressed by astrocytes and pericytes and, to a lesser extent, by endothelial cells. Endothelial cells were extremely susceptible to cell death when OGD was applied to mimic in vitro the cytotoxicity induced by ischemia, whereas astrocytes and pericytes were more resistant. A semi-quantitative assay highlighted markedly increased e-ATPase activity following exposure to OGD in all three cell types, either when grown separately or when co-cultured together to resemble the composition of the BBB. Moreover, electron microscopy analysis showed that both endothelial cells and astrocytes shed microvesicles containing NTPDases from their membrane, which may suggest a novel mechanism to increase the breakdown of ATP released to toxic levels by damaged BBB cells. We hypothesize that this phenomenon could have a protective and/or modulatory effect for brain parenchymal cells. This in vitro model is therefore useful to study the role of extracellular nucleotides in modulating BBB responses to ischemic events, and to develop new effective purinergic-based approaches for brain ischemia.

  9. Effects of Reduced Oxygen and Glucose Levels on Ocular Cells in vitro: Implications for Tissue Models

    OpenAIRE

    Sander, Edward A.; Nauman, Eric A.

    2009-01-01

    An important goal of tissue engineering is the development of better in vitro tissue models for the study and treatment of diseases, especially those that are difficult to model in animals, such as glaucoma. In order to properly interpret experimental results designed to mimic in vivo conditions, it is necessary to characterize the metabolic state of the in vitro culture. The goal of this study was to determine how porcine lamina cribrosa cells (PLC), porcine scleral fibroblasts (PSC) and rat...

  10. Sex- and Tissue-Specific Methylome Changes in Brains of Mice Perinatally Exposed to Lead

    Science.gov (United States)

    Sánchez-Martín, Francisco Javier; Lindquist, Diana M.; Landero-Figueroa, Julio; Zhang, Xiang; Chen, Jing; Cecil, Kim M.; Medvedovic, Mario; Puga, Alvaro

    2014-01-01

    Changes in DNA methylation and subsequent changes in gene expression regulation are the hallmarks of age- and tissue-dependent epigenetic drift and plasticity resulting from the combinatorial integration of genetic determinants and environmental cues. To determine whether perinatal lead exposure caused persistent DNA methylation changes in target tissues, we exposed mouse dams to 0, 3 or 30 ppm of lead acetate in drinking water for a period extending from 2 months prior to mating, through gestation, until weaning of pups at postnatal day-21, and analyzed whole-genome DNA methylation in brain cortex and hippocampus of 2-month old exposed and unexposed progeny. Lead exposure resulted in hypermethylation of three differentially methylated regions in the hippocampus of females, but not males. These regions mapped to Rn4.5s, Sfi1, and Rn45s loci in mouse chromosomes 2, 11 and 17, respectively. At a conservative fdr<0.001, 1,623 additional CpG sites were differentially methylated in female hippocampus, corresponding to 117 unique genes. Sixty of these genes were tested for mRNA expression and showed a trend towards negative correlation between mRNA expression and methylation in exposed females but not males. No statistically significant methylome changes were detected in male hippocampus or in cortex of either sex. We conclude that exposure to lead during embryonic life, a time when the organism is most sensitive to environmental cues, appears to have a sex- and tissue-specific effect on DNA methylation that may produce pathological or physiological deviations from the epigenetic plasticity operative in unexposed mice. PMID:25530354

  11. Extra corporeal membrane oxygenation in newborns : implications for brain and lung

    OpenAIRE

    Heijst, Adrianus Franciscus Jacobus van

    2004-01-01

    Extracorporeal membrane oxygenation (ECMO) is a rescue treatment for newborns with severe respiratory insufficiency. In veno-arterial ECMO, venous blood is drained from the right atrium, oxygenated in an artificial lung and reinfused in the aorta. For vascular access the right internal jugular vein and right common carotid artery are ligated permanently. This invasive treatment may have major complications. In this thesis we described the results of ECMO treatment in the University Medical Ce...

  12. Persistent resetting of the cerebral oxygen/glucose uptake ratio by brain activation

    DEFF Research Database (Denmark)

    Madsen, P L; Hasselbalch, S G; Hagemann, L P;

    1995-01-01

    Global cerebral blood flow (CBF), global cerebral metabolic rates for oxygen (CMRO2), and for glucose (CMRglc), and lactate efflux were measured during rest and during cerebral activation induced by the Wisconsin card sorting test. Measurements were performed in healthy volunteers using the Kety...... stress indicators returned to baseline values. Activation-induced resetting of the cerebral oxygen/glucose uptake ratio is not necessarily accounted for by increased lactate production from nonoxidative glucose metabolism....

  13. Oxygen saturation, red blood cell tissue fraction and speed resolved perfusion - A new optical method for microcirculatory assessment.

    Science.gov (United States)

    Jonasson, Hanna; Fredriksson, Ingemar; Pettersson, Anders; Larsson, Marcus; Strömberg, Tomas

    2015-11-01

    We have developed a new fiber-optic system that combines diffuse reflectance spectroscopy (DRS) and laser Doppler Flowmetry (LDF) for a multi-modal assessment of the microcirculation. Quantitative data is achieved with an inverse Monte Carlo algorithm based on an individually adaptive skin model. The output parameters are calculated from the model and given in absolute units: hemoglobin oxygen saturation (%), red blood cell (RBC) tissue fraction (%), and the speed resolved RBC perfusion separated into three speed regions; 0-1mm/s, 1-10mm/s and above 10mm/s (% mm/s). The aim was to explore microcirculatory parameters using the new optical method, integrating DRS and LDF in a joint skin model, during local heating of the dorsal foot and venous and arterial occlusion of the forearm in 23 healthy subjects (age 20-28years). There were differences in the three speed regions in regard to blood flow changes due to local heating, where perfusion for high speeds increased the most. There was also a high correlation between changes in oxygenation and changes in perfusion for higher speeds. Oxygen saturation at baseline was 44% on foot, increasing to 83% at plateau after heating. The larger increase in perfusion for higher speeds than for lower speeds together with the oxygenation increase during thermal provocation, shows a local thermoregulatory blood flow in presumably arteriolar dermal vessels. In conclusion, there are improved possibilities to assess microcirculation using integrated DRS and LDF in a joint skin model by enabling both oxygenation and speed resolved blood flow assessment simultaneously and in the same skin site. Output parameters in absolute units may also yield new insights about the microcirculatory system.

  14. The post-synaptic density of human postmortem brain tissues: an experimental study paradigm for neuropsychiatric illnesses.

    Directory of Open Access Journals (Sweden)

    Chang-Gyu Hahn

    Full Text Available Recent molecular genetics studies have suggested various trans-synaptic processes for pathophysiologic mechanisms of neuropsychiatric illnesses. Examination of pre- and post-synaptic scaffolds in the brains of patients would greatly aid further investigation, yet such an approach in human postmortem tissue has yet to be tested. We have examined three methods using density gradient based purification of synaptosomes followed by detergent extraction (Method 1 and the pH based differential extraction of synaptic membranes (Methods 2 and 3. All three methods separated fractions from human postmortem brains that were highly enriched in typical PSD proteins, almost to the exclusion of pre-synaptic proteins. We examined these fractions using electron microscopy (EM and verified the integrity of the synaptic membrane and PSD fractions derived from human postmortem brain tissues. We analyzed protein composition of the PSD fractions using two dimensional liquid chromatography tandem mass spectrometry (2D LC-MS/MS and observed known PSD proteins by mass spectrometry. Immunoprecipitation and immunoblot studies revealed that expected protein-protein interactions and certain posttranscriptional modulations were maintained in PSD fractions. Our results demonstrate that PSD fractions can be isolated from human postmortem brain tissues with a reasonable degree of integrity. This approach may foster novel postmortem brain research paradigms in which the stoichiometry and protein composition of specific microdomains are examined.

  15. Contents of myelin-basic protein and S-100 in serum and brain tissue of neonatal rats with intrauterine infection-caused brain injury

    Institute of Scientific and Technical Information of China (English)

    Xiaojie Li; Hongying Li; Zhihai Lu

    2006-01-01

    BACKGROUND: The change of the content of myelin basic protein (MBP) in serum and brain tissue is the bio chemical diadynamic index of amyelination. S-100 is a specific and sensitive marker of central nervous system (CNS) injury. Whether or not the content of S-100 and MBP in blood and brain tissue can be used as the quan titative index for early diagnosing the intrauterine infection-caused brain injury still needs investigation. OBJECTIVE: To observe whether or not MBP and S-100 detection can be used as the biochemical indexes for early diagnosing the intrauterine infection-caused brain injury. DESIGN: Randomized controlled animal experiment. SETTING: Laboratory of Pediatric Neuro-rehabilitation, Medical College of Rehabilitation, Jiamusi University. MATERIALS: Sixty female and thirty male common Wistar rats, weighing from 180 to 240 g, were provided by the Experimental Animal Center of Jiamusi University. Reagent: Lipopolysaccharide(LPS, serological type 055: B5, SIGMA Company of USA); MBP enzyme linked immunosobent assay (ELISA) immunoreagent kit (Preclinicai Recombination DNA Laboratory, Chengdu Huaxi Medical Center, Sichuan Province); S-100 ELISA immunoreagent kit ( Department of Physiology, the Fourth Military Medical University of Chinese PLA) and bovine serum albumin(Haitaike Biotechnology Co.,Ltd.).METHODS: This experiment was carried out in the Laboratory of Pediatric Neuro-Rehabilitation, Experimental Animal Center, Department of Pathology and Central Laboratory of Jiamusi University from July 2005 to March 2006. ① Preparation of models and grouping: The female and male rats were placed in one cage at 2: 1 at 17:00 o'clock. Vaginal smear was checked at 8:00 on the next morning. Sperm was found and 0 day of pregnancy was recorded. Pregnant rats were bred in another cage. The pregnant 47 rats were randomly divided into 2 groups: control group (n =10) and experimental group (n =37). The experimental pregnant rats were intraperitoneally injected with LPS

  16. On the consequences of non linear constitutive modelling of brain tissue for injury prediction with numerical head models

    NARCIS (Netherlands)

    Hrapko, M.; Dommelen, J.A.W. van; Peters, G.W.M.; Wismans, J.S.H.M.

    2009-01-01

    The objective of this work was to investigate the influences of constitutive non linearities of brain tissue in numerical head model simulations by comparing the performance of a recently developed non linear constitutive model [10, 11] with a simplified version, based on neo-Hookean elastic behavio

  17. Transient hyperoxia does not affect regional cerebral tissue oxygen saturation in moderately preterm or term newborns

    DEFF Research Database (Denmark)

    Thing, Mira; Sørensen, Line Carøe; Pryds, Ole

    2015-01-01

    oxygen saturation (rStO2 ) and to evaluate whether any observed prolonged cerebral vasoconstriction was related to maturity. METHODS: The study included 30 infants with a postmenstrual age of more than 32 weeks, who were treated with nasal continuous positive airway pressure and a fraction of inspired......, with a mean difference of 1.37% (95% CI 0.15, 2.6). After the second oxygen exposure, rStO2 remained unchanged with a mean difference of -0.4% (95% CI -1.6, 0.78). Differences in rStO2 were not related to gestational age in either of the two hyperoxic episodes. CONCLUSION: We found no evidence to support...... the theory that transient hyperoxia induces prolonged cerebral vasoconstriction in infants with a postmenstrual age above 32 weeks....

  18. Early dietary intervention with structured triacylglycerols containing docosahexaenoic acid. Effect on brain, liver, and adipose tissue lipids

    DEFF Research Database (Denmark)

    Christensen, Merete Myrup; Høy, Carl-Erik

    1997-01-01

    and received ordinary rat chow at weaning. In general no significant differences between the two dietary treatments wereobserved in the tissues examined except for adipose tissue. The levels of 22:6n-3 were significantly increased in brain phosphatidylcholines (PC) andphosphatidylserines (PS) of both...... in the experimental groups than in the reference group. In adipose tissue, 22:6n-3increased in the experimental groups during the study period, but decreased in the reference group, suggesting that a surplus of dietary 22:6n-3 wasstored....

  19. Intra-arterial tert-Butyl-Hydroperoxide Infusion Induces an Exacerbated Sensory Response in the Rat Hind Limb and is Associated with an Impaired Tissue Oxygen Uptake

    OpenAIRE

    Tan, Edward C. T. H.; van Goor, Harry; Bahrami, Soheyl; Kozlov, Andrey V; Leixnering, Martin; Redl, Heinz; Goris, R. Jan A.

    2010-01-01

    The objective of this study was to investigate oxidative stress and oxygen extraction mechanisms in an animal model of continuous intra-arterial infusion of a free radical donor and in an in vitro model using isolated mitochondria. tert-Butyl-hydroperoxide (tert-BuOOH, 25 mM) was infused for 24 h in the left hind limb of rats to induce soft tissue damage (n = 8). After 7 days, we assessed local sensory response, tissue oxygen consumption, oxygen radicals, and antioxidant levels. In vitro mito...

  20. Pilot study to visualise and measure skin tissue oxygenation, erythema, total haemoglobin and melanin content using index maps in healthy controls

    Science.gov (United States)

    Poxon, Ian; Wilkinson, Jack; Herrick, Ariane; Dickinson, Mark; Murray, Andrea

    2014-02-01

    We report on a method for analysing multispectral images of skin in vivo for the measurement and visualisation of skin characteristics. Four different indices were used to characterise skin tissue oxygenation, erythema, total haemoglobin and melanin content. Index values were calculated pixel-wise and combined to create index maps to visualise skin properties. Quantitative measurement of tissue oxygenation saturation was possible by calibrating the oxygenation index using a commercial, calibrated oximeter. Index maps were tested by arterial occlusion of the index finger with multispectral images taken before, during and after occlusion in a pilot study with 10 healthy controls.

  1. A stereotaxic, population-averaged T1w ovine brain atlas including cerebral morphology and tissue volumes

    Directory of Open Access Journals (Sweden)

    Björn eNitzsche

    2015-06-01

    Full Text Available Standard stereotaxic reference systems play a key role in human brain studies. Stereotaxic coordinate systems have also been developed for experimental animals including non-human primates, dogs and rodents. However, they are lacking for other species being relevant in experimental neuroscience including sheep. Here, we present a spatial, unbiased ovine brain template with tissue probability maps (TPM that offer a detailed stereotaxic reference frame for anatomical features and localization of brain areas, thereby enabling inter-individual and cross-study comparability. Three-dimensional data sets from healthy adult Merino sheep (Ovis orientalis aries, 12 ewes and 26 neutered rams were acquired on a 1.5T Philips MRI using a T1w sequence. Data were averaged by linear and non-linear registration algorithms. Moreover, animals were subjected to detailed brain volume analysis including examinations with respect to body weight, age and sex. The created T1w brain template provides an appropriate population-averaged ovine brain anatomy in a spatial standard coordinate system. Additionally, TPM for gray (GM and white (WM matter as well as cerebrospinal fluid (CSF classification enabled automatic prior-based tissue segmentation using statistical parametric mapping (SPM. Overall, a positive correlation of GM volume and body weight explained about 15% of the variance of GM while a positive correlation between WM and age was found. Absolute tissue volume differences were not detected, indeed ewes showed significantly more GM per bodyweight as compared to neutered rams. The created framework including spatial brain template and TPM represent a useful tool for unbiased automatic image preprocessing and morphological characterization in sheep. Therefore, the reported results may serve as a starting point for further experimental and/or translational research aiming at in vivo analysis in this species.

  2. Resected Brain Tissue, Seizure Onset Zone and Quantitative EEG Measures: Towards Prediction of Post-Surgical Seizure Control.

    Directory of Open Access Journals (Sweden)

    Christian Rummel

    Full Text Available Epilepsy surgery is a potentially curative treatment option for pharmacoresistent patients. If non-invasive methods alone do not allow to delineate the epileptogenic brain areas the surgical candidates undergo long-term monitoring with intracranial EEG. Visual EEG analysis is then used to identify the seizure onset zone for targeted resection as a standard procedure.Despite of its great potential to assess the epileptogenicty of brain tissue, quantitative EEG analysis has not yet found its way into routine clinical practice. To demonstrate that quantitative EEG may yield clinically highly relevant information we retrospectively investigated how post-operative seizure control is associated with four selected EEG measures evaluated in the resected brain tissue and the seizure onset zone. Importantly, the exact spatial location of the intracranial electrodes was determined by coregistration of pre-operative MRI and post-implantation CT and coregistration with post-resection MRI was used to delineate the extent of tissue resection. Using data-driven thresholding, quantitative EEG results were separated into normally contributing and salient channels.In patients with favorable post-surgical seizure control a significantly larger fraction of salient channels in three of the four quantitative EEG measures was resected than in patients with unfavorable outcome in terms of seizure control (median over the whole peri-ictal recordings. The same statistics revealed no association with post-operative seizure control when EEG channels contributing to the seizure onset zone were studied.We conclude that quantitative EEG measures provide clinically relevant and objective markers of target tissue, which may be used to optimize epilepsy surgery. The finding that differentiation between favorable and unfavorable outcome was better for the fraction of salient values in the resected brain tissue than in the seizure onset zone is consistent with growing evidence that

  3. Three-dimensional visualization of functional brain tissue and functional magnetic resonance imaging-integrated neuronavigation in the resection of brain tumor adjacent to motor cortex

    International Nuclear Information System (INIS)

    Objective: To assess the value of three -dimensional visualization of functional brain tissue and the functional magnetic resonance imaging (fMRI)-integrated neuronavigation in the resection of brain tumor adjacent to motor cortex. Method: Sixty patients with tumor located in the central sulcus were enrolled. Thirty patients were randomly assigned to function group and 30 to control group. Patients in function group underwent fMRI to localize the functional brain tissues. Then the function information was transferred to the neurosurgical navigator. The patients in control group underwent surgery with navigation without function information. The therapeutic effect, excision rate. improvement of motor function, and survival quality during follow-up were analyzed. Result: All patients in function group were accomplished visualization of functional brain tissues and fMRI-integrated neuronavigation. The locations of tumors, central sulcus and motor cortex were marked during the operation. The fMRI -integrated information played a great role in both pre- and post-operation. Pre-operation: designing the location of the skin flap and window bone, determining the relationship between the tumor and motor cortex, and designing the pathway for the resection. Post- operation: real-time navigation of relationship between the tumor and motor cortex, assisting to localize the motor cortex using interoperation ultra-sound for correcting the displacement by the CSF outflow and collapsing tumor. The patients in the function group had better results than the patients in the control group in therapeutic effect (u=2.646, P=0.008), excision rate (χ=7.200, P<0.01), improvement of motor function (u=2.231, P=0.026), and survival quality (KPS uc= 2.664, P=0.008; Zubrod -ECOG -WHO uc=2.135, P=0.033). Conclusions: Using preoperative three -dimensional visualization of cerebral function tissue and the fMRI-integrated neuronavigation technology, combining intraoperative accurate positioning

  4. Gestational age dependent changes of the fetal brain, liver and adipose tissue fatty acid compositions in a population with high fish intakes

    NARCIS (Netherlands)

    Kuipers, Remko S.; Luxwolda, Martine F.; Offringa, Pieter J.; Boersma, E. Rudy; Dijck-Brouwer, D. A. Janneke; Muskiet, Frits A. J.

    2012-01-01

    Introduction: There are no data on the intrauterine fatty acid (FA) compositions of brain, liver and adipose tissue of infants born to women with high fish intakes. Subjects and methods: We analyzed the brain (n = 18), liver (n = 14) and adipose tissue (n = 11) FA compositions of 20 stillborn infant

  5. Uniform distributions of glucose oxidation and oxygen extraction in gray matter of normal human brain: No evidence of regional differences of aerobic glycolysis.

    Science.gov (United States)

    Hyder, Fahmeed; Herman, Peter; Bailey, Christopher J; Møller, Arne; Globinsky, Ronen; Fulbright, Robert K; Rothman, Douglas L; Gjedde, Albert

    2016-05-01

    Regionally variable rates of aerobic glycolysis in brain networks identified by resting-state functional magnetic resonance imaging (R-fMRI) imply regionally variable adenosine triphosphate (ATP) regeneration. When regional glucose utilization is not matched to oxygen delivery, affected regions have correspondingly variable rates of ATP and lactate production. We tested the extent to which aerobic glycolysis and oxidative phosphorylation power R-fMRI networks by measuring quantitative differences between the oxygen to glucose index (OGI) and the oxygen extraction fraction (OEF) as measured by positron emission tomography (PET) in normal human brain (resting awake, eyes closed). Regionally uniform and correlated OEF and OGI estimates prevailed, with network values that matched the gray matter means, regardless of size, location, and origin. The spatial agreement between oxygen delivery (OEF≈0.4) and glucose oxidation (OGI ≈ 5.3) suggests that no specific regions have preferentially high aerobic glycolysis and low oxidative phosphorylation rates, with globally optimal maximum ATP turnover rates (VATP ≈ 9.4 µmol/g/min), in good agreement with (31)P and (13)C magnetic resonance spectroscopy measurements. These results imply that the intrinsic network activity in healthy human brain powers the entire gray matter with ubiquitously high rates of glucose oxidation. Reports of departures from normal brain-wide homogeny of oxygen extraction fraction and oxygen to glucose index may be due to normalization artefacts from relative PET measurements. PMID:26755443

  6. Effect of nicardipine combined with esmolol on systemic and tissue oxygenation during off-pump coronary artery bypass grafting surgery

    Institute of Scientific and Technical Information of China (English)

    WANG Tian-long; JIANG Yan; YANG Ba-xian

    2005-01-01

    Background The hemodynamics and oxygenation severely fluctuated during the off-pump coronary artery bypass grafting (OPCABG). This study aimed at investigating whether or not nicardipine combined with esmolol (1∶ 10) can maintain systemic and tissue oxygenation during OPCABG.Methods Twenty patients scheduled for OPCABG were divided ramdomly into Group nicardipine (N) and Group nitroglycerine (X) respectively combined with esmolol (E) (Dosage ratio: 1 to 10) (Group N+E and Group X+E) with 10 patients in each group. The mixed solution of N+E or X+E were titrated to maintain mean arterial blood pressure between 70 and 80 mmHg following anesthesia induction. The variables of hemodynamics, arterial blood lactate content (Lac) and gastric intramucosal partial pressure of carbon dioxide were measured at the following time points: after induction of anesthesia (T1), pre-revascularization (T2), grafting of left anterior descending (T3), right coronary descending (T4) and left coronary circumflexus branches (T5), post-revascularization (T6), the end of operation (T7). The delivery of oxygen (DO2), consumption of oxygen (VO2) and gastric intramucosal pH (pHi) were calculated.Results The cardiac index (CI) in Group N+E was significantly increased (P<0.05) as compared with T1 during OPCABG, while it was mildly decreased in Group X+E. The stroke volumes at T4, T5 in Group N+E and at T3-T6 in Group X+E were significantly decreased (P<0.05). The systemic vascular resistance indices in Group N+E were significantly decreased as compared with T1 (P<0.05). The heart rates in these two Groups were significantly elevated intraoperatively (P<0.05). The DO2 after the infusion of N+E was significantly increased (P<0.05) or leveled to T1, and the Lac were within the normal range. But the DO2 in Group X+E was decreased throughout the procedure, reaching significant level at T5 (P<0.05), and the Lac was significantly increased beyond normal range (P<0.05). The pHi in Group N+E was

  7. Neural network-based brain tissue segmentation in MR images using extracted features from intraframe coding in H.264

    Science.gov (United States)

    Jafari, Mehdi; Kasaei, Shohreh

    2012-01-01

    Automatic brain tissue segmentation is a crucial task in diagnosis and treatment of medical images. This paper presents a new algorithm to segment different brain tissues, such as white matter (WM), gray matter (GM), cerebral spinal fluid (CSF), background (BKG), and tumor tissues. The proposed technique uses the modified intraframe coding yielded from H.264/(AVC), for feature extraction. Extracted features are then imposed to an artificial back propagation neural network (BPN) classifier to assign each block to its appropriate class. Since the newest coding standard, H.264/AVC, has the highest compression ratio, it decreases the dimension of extracted features and thus yields to a more accurate classifier with low computational complexity. The performance of the BPN classifier is evaluated using the classification accuracy and computational complexity terms. The results show that the proposed technique is more robust and effective with low computational complexity compared to other recent works.

  8. Absolute Oxygenation Metabolism Measurements Using Magnetic Resonance Imaging

    OpenAIRE

    An, Hongyu; Liu, Qingwei; Eldeniz, Cihat; Lin, Weili

    2011-01-01

    Cerebral oxygen metabolism plays a critical role in maintaining normal function of the brain. It is the primary energy source to sustain neuronal functions. Abnormalities in oxygen metabolism occur in various neuro-pathologic conditions such as ischemic stroke, cerebral trauma, cancer, Alzheimer’s disease and shock. Therefore, the ability to quantitatively measure tissue oxygenation and oxygen metabolism is essential to the understanding of pathophysiology and treatment of various diseases. T...

  9. Hyperbaric oxygen therapy as a potential treatment for post-traumatic stress disorder associated with traumatic brain injury

    Science.gov (United States)

    Eve, David J; Steele, Martin R; Sanberg, Paul R; Borlongan, Cesar V

    2016-01-01

    Traumatic brain injury (TBI) describes the presence of physical damage to the brain as a consequence of an insult and frequently possesses psychological and neurological symptoms depending on the severity of the injury. The recent increased military presence of US troops in Iraq and Afghanistan has coincided with greater use of improvised exploding devices, resulting in many returning soldiers suffering from some degree of TBI. A biphasic response is observed which is first directly injury-related, and second due to hypoxia, increased oxidative stress, and inflammation. A proportion of the returning soldiers also suffer from post-traumatic stress disorder (PTSD), and in some cases, this may be a consequence of TBI. Effective treatments are still being identified, and a possible therapeutic candidate is hyperbaric oxygen therapy (HBOT). Some clinical trials have been performed which suggest benefits with regard to survival and disease severity of TBI and/or PTSD, while several other studies do not see any improvement compared to a possibly poorly controlled sham. HBOT has been shown to reduce apoptosis, upregulate growth factors, promote antioxidant levels, and inhibit inflammatory cytokines in animal models, and hence, it is likely that HBOT could be advantageous in treating at least the secondary phase of TBI and PTSD. There is some evidence of a putative prophylactic or preconditioning benefit of HBOT exposure in animal models of brain injury, and the optimal time frame for treatment is yet to be determined. HBOT has potential side effects such as acute cerebral toxicity and more reactive oxygen species with long-term use, and therefore, optimizing exposure duration to maximize the reward and decrease the detrimental effects of HBOT is necessary. This review provides a summary of the current understanding of HBOT as well as suggests future directions including prophylactic use and chronic treatment. PMID:27799776

  10. Quantification of Neurotransmitters in Mouse Brain Tissue by Using Liquid Chromatography Coupled Electrospray Tandem Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Tae-Hyun Kim

    2014-01-01

    Full Text Available A simple and rapid liquid chromatography tandem mass spectrometry method has been developed for the determination of BH4, DA, 5-HT, NE, EP, Glu, and GABA in mouse brain using epsilon-acetamidocaproic acid and isotopically labeled neurotransmitters as internal standards. Proteins in the samples were precipitated by adding acetonitrile, and then the supernatants were separated by a Sepax Polar-Imidazole (2.1 mm × 100 mm, i.d., 3 μm column by adding a mixture of 10 mM ammonium formate in acetonitrile/water (75 : 25, v/v, 300 μl/min for BH4 and DA. To assay 5-HT, NE, EP, Glu, and GABA; a Luna 3 μ C18 (3.0 mm × 150 mm, i.d., 3 μm column was used by adding a mixture of 1% formic acid in acetonitrile/water (20 : 80, v/v, 350 μl/min. The total chromatographic run time was 5.5 min. The method was validated for the analysis of samples. The calibration curve was linear between 10 and 2000 ng/g for BH4 r2=0.995, 10 and 5000 ng/g for DA r2=0.997, 20 and 10000 ng/g for 5-HT r2=0.994, NE r2=0.993, and EP r2=0.993, and 0.2 and 200 μg/g for Glu r2=0.996 and GABA r2=0.999 in the mouse brain tissues. As stated above, LC-MS/MS results were obtained and established to be a useful tool for the quantitative analysis of BH4, DA, 5-HT, NE, EP, Glu, and GABA in the experimental rodent brain.

  11. Alteration in regional tissue oxygenation of preterm infants during placement in the semi-upright seating position.

    Science.gov (United States)

    Petrova, Anna; Mehta, Rajeev

    2015-01-01

    We investigated whether the cerebral (rSO2-C %) and renal (rSO2-R %) tissue oxygenation of preterm infants is altered by repositioning from the supine to semi-upright position for pre-discharge car seat testing. Near-infrared spectroscopy was used to measure rSO2-C and rSO2-R, which were recorded simultaneously with vital signs in 15 preterm infants for 30 minutes in supine, 60 minutes in the semi-upright (at 45 degrees in a car seat), and 30 minutes in the post-semi-upright (supine) position. Changes in rSO2-C and SO2-R were mostly within 1 Standard Deviation (SD) of baseline mean levels in the supine position. Decrease in rSO2-C and rSO2-R (more than 1SD below baseline mean) was recorded in 26.7% and 6.6% of infants respectively, which persisted even after adjustment for variation in heart and respiratory rate, and pulse oximeter measured oxygen saturation (P, 0.0001). Re-positioning the infants from the car seat to supine position was associated with normalization of the rSO2-C. Alteration in rSO2-C and rSO2-R in a car seat was independent from the gestational and post-conception age, weight and presence of anemia. We concluded that approximately one-third of preterm infants show minor reduction of cerebral tissue oxygenation in the semi-upright (car seat) position. PMID:25661986

  12. The association between brain natriuretic peptide and tissue Doppler parameters in children with hypertrophic cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Taliha Öner

    2016-01-01

    Full Text Available In this study, we investigated the association between brain natriuretic peptide (BNP levels and tissue Doppler imaging measurements and also screening for deadly mutations in patients with hypertrophic cardiomyopathy (HCM. We enrolled 20 patients diagnosed with HCM (age:10.7±5 years (1-17, 85% male, weight:42.25±23.10 kg, height:141.80±32.45 cm and 20 age, gender and body weight-matched control subjects. We performed electrocardiography, transthoracic echocardiography, and tissue Doppler echocardiography in each group, as well as genetic tests (for Arg403Gln, Arg453Cys, Arg719Trp and Arg719Gln mutations in MYH7 Exons 13, 14, 19 and BNP in the patients. The patients were divided into two groups according to the presence (Group 1 or absence (Group 2 of left ventricular (LV outflow tract obstruction. QTc dispersion and the LV ejection fraction and left atrial (LA volume index were increased in Group 1. The LA volume index and the mitral and septal E/Ea ratio and septum Z-score were increased while the mitral lateral annulus and septal annulus Ea wave velocities and the mitral and tricuspid E/A ratio were decreased in patients with high levels of BNP compared to those with normal BNP levels. There were no mutations that are associated with increased risk of sudden death found in patients included in this study. In the light of our data, we conclude that such parameters BNP levels above the 98 pg/mL, septal thickness Z-score ˃6, and higher mitral and septal E/Ea ratios can be used for management of patients with HCM according to life-threatening conditions.

  13. Tissomics: two- and three-dimensional distribution of nuclei in brain tissue using laser scanning cytometry (LSC)

    Science.gov (United States)

    Lenz, Domnik; Mittag, Anja; Mosch, Birgit; Bocsi, Jozsef; Arendt, Thomas; Tarnok, Attila

    2005-03-01

    Automated quantitative (i.e. stochiometric) analysis of tissues is of eminent importance in the understanding of all interactions between cells in their natural environment. In tissue cytometry a solid trigger is necessary in order to unequivocally differentiate between cellular and non-cellular events. This can be best performed by nuclear staining. Aim of this study was to analyze a brain tissue section by laser scanning cytometry (LSC) in order to depict the threedimensional distribution of nuclei in the tissue. To this end the section was measured in several foci and different nuclei detected in several depths of the tissue were assigned to the respective layer. Frozen sections of formalin-fixed rat or human brain tissue (120μm thickness) were incubated with propidiumiodide (PI) (50μg/ml) and covered on slides. For analysis by the LSC propidiumiodide was used as trigger. After a first analysis focussed on the top of the tissue, the focus was adjusted in 30μm steps deeper into the tissue. Per analysis data of at least 50,000 cells were acquired. After finishing measurements from all depths of the field were merged, i.e. data were combined into a composite data file. With the special features of the LSC it was possible to develop a method depicting the threedimensional distribution of the nuclei in solid tissue sections. LSC can be useful tool for this relatively new field of solid tissue cytometry termed tissomics. After evaluation of methods like this, so far not available data can be analysed for diagnostic purposes. By these studies we intend to demonstrate the power of the LSC for the routine pathological use. This should add up to the bright versatility of applications for the LSC as a cytometric instrument suitable for high throughput and high content analysis.

  14. Tissue plasminogen activator followed by antioxidant-loaded nanoparticle delivery promotes activation/mobilization of progenitor cells in infarcted rat brain.

    Science.gov (United States)

    Petro, Marianne; Jaffer, Hayder; Yang, Jun; Kabu, Shushi; Morris, Viola B; Labhasetwar, Vinod

    2016-03-01

    Inherent neuronal and circulating progenitor cells play important roles in facilitating neuronal and functional recovery post stroke. However, this endogenous repair process is rather limited, primarily due to unfavorable conditions in the infarcted brain involving reactive oxygen species (ROS)-mediated oxidative stress and inflammation following ischemia/reperfusion injury. We hypothesized that during reperfusion, effective delivery of antioxidants to ischemic brain would create an environment without such oxidative stress and inflammation, thus promoting activation and mobilization of progenitor cells in the infarcted brain. We administered recombinant human tissue-type plasminogen activator (tPA) via carotid artery at 3 h post stroke in a thromboembolic rat model, followed by sequential administration of the antioxidants catalase (CAT) and superoxide dismutase (SOD), encapsulated in biodegradable nanoparticles (nano-CAT/SOD). Brains were harvested at 48 h post stroke for immunohistochemical analysis. Ipsilateral brain slices from animals that had received tPA + nano-CAT/SOD showed a widespread distribution of glial fibrillary acidic protein-positive cells (with morphology resembling radial glia-like neural precursor cells) and nestin-positive cells (indicating the presence of immature neurons); such cells were considerably fewer in untreated animals or those treated with tPA alone. Brain sections from animals receiving tPA + nano-CAT/SOD also showed much greater numbers of SOX2- and nestin-positive progenitor cells migrating from subventricular zone of the lateral ventricle and entering the rostral migratory stream than in t-PA alone treated group or untreated control. Further, animals treated with tPA + nano-CAT/SOD showed far fewer caspase-positive cells and fewer neutrophils than did other groups, as well as an inhibition of hippocampal swelling. These results suggest that the antioxidants mitigated the inflammatory response, protected neuronal cells

  15. Variable ATP yields and uncoupling of oxygen consumption in human brain

    DEFF Research Database (Denmark)

    Gjedde, Albert; Aanerud, Joel; Peterson, Ericka;

    2011-01-01

    normalized the metabolic rate to the population average of that region. Coefficients of variation ranged from 10 to 15% in the different regions of the human brain and the normalized regional metabolic rates ranged from 70% to 140% of the population average for each region, equal to a two-fold variation...

  16. Functional Oxygen Sensitivity of Astrocytes.

    Science.gov (United States)

    Angelova, Plamena R; Kasymov, Vitaliy; Christie, Isabel; Sheikhbahaei, Shahriar; Turovsky, Egor; Marina, Nephtali; Korsak, Alla; Zwicker, Jennifer; Teschemacher, Anja G; Ackland, Gareth L; Funk, Gregory D; Kasparov, Sergey; Abramov, Andrey Y; Gourine, Alexander V

    2015-07-22

    In terrestrial mammals, the oxygen storage capacity of the CNS is limited, and neuronal function is rapidly impaired if oxygen supply is interrupted even for a short period of time. However, oxygen tension monitored by the peripheral (arterial) chemoreceptors is not sensitive to regional CNS differences in partial pressure of oxygen (PO2 ) that reflect variable levels of neuronal activity or local tissue hypoxia, pointing to the necessity of a functional brain oxygen sensor. This experimental animal (rats and mice) study shows that astrocytes, the most numerous brain glial cells, are sensitive to physiological changes in PO2 . Astrocytes respond to decreases in PO2 a few millimeters of mercury below normal brain oxygenation with elevations in intracellular calcium ([Ca(2+)]i). The hypoxia sensor of astrocytes resides in the mitochondria in which oxygen is consumed. Physiological decrease in PO2 inhibits astroglial mitochondrial respiration, leading to mitochondrial depolarization, production of free radicals, lipid peroxidation, activation of phospholipase C, IP3 receptors, and release of Ca(2+) from the intracellular stores. Hypoxia-induced [Ca(2+)]i increases in astrocytes trigger fusion of vesicular compartments containing ATP. Blockade of astrocytic signaling by overexpression of ATP-degrading enzymes or targeted astrocyte-specific expression of tetanus toxin light chain (to interfere with vesicular release mechanisms) within the brainstem respiratory rhythm-generating circuits reveals the fundamental physiological role of astroglial oxygen sensitivity; in low-oxygen conditions (environmental hypoxia), this mechanism increases breathing activity even in the absence of peripheral chemoreceptor oxygen sensing. These results demonstrate that astrocytes are functionally specialized CNS oxygen sensors tuned for rapid detection of physiological changes in brain oxygenation. Significance statement: Most, if not all, animal cells possess mechanisms that allow them to

  17. Modulation of lipid peroxidation, hypolipidemic and antioxidant activities in brain tissues of diabetic rats by fibre - Enriched biscuits

    Institute of Scientific and Technical Information of China (English)

    Ochuko L Erukainure; Folasade O Adeboyejo; Gloria N Elemo; Osaretin AT Ebuehi

    2012-01-01

    Objective: To investigate the effect of feeding fibre - enriched biscuit on the antioxidant and hypolipidemic activities in brain tissues of diabetic rats. Method: Diabetes was induced by a single intraperitoneal injection of alloxan. Treatment lasted for 14 d, after which the rats were sacrificed by cervical dislocation. Brain tissues were used for the assessment of GSH, catalase, SOD and lipid peroxidation as well as lipid profiles. Result: Induction of diabetes led to a significant decrease in GSH level, elevated SOD and catalase activities. These were significantly modified by the biscuits. There was an elevated level of malondialdehyde in the brain tissues of the untreated diabetic rats; this was significantly reduced by the biscuits. There was a significant decrease in HDL and a significant increase in LDL levels, total cholesterol and triglycerides in the untreated (diabetic) rats. Feeding with fibre - enriched biscuits led to decrease in the levels of total cholesterol, triglyceride, LDL - cholesterol and caused a significant increase in the levels of HDL. Conclusions: These results suggest a therapeutic and protective effect of the fibre -enriched biscuits against diabetic - induced brain toxicity in rats.

  18. Improved two-photon imaging of living neurons in brain tissue through temporal gating.

    Science.gov (United States)

    Gautam, Vini; Drury, Jack; Choy, Julian M C; Stricker, Christian; Bachor, Hans-A; Daria, Vincent R

    2015-10-01

    We optimize two-photon imaging of living neurons in brain tissue by temporally gating an incident laser to reduce the photon flux while optimizing the maximum fluorescence signal from the acquired images. Temporal gating produces a bunch of ~10 femtosecond pulses and the fluorescence signal is improved by increasing the bunch-pulse energy. Gating is achieved using an acousto-optic modulator with a variable gating frequency determined as integral multiples of the imaging sampling frequency. We hypothesize that reducing the photon flux minimizes the photo-damage to the cells. Our results, however, show that despite producing a high fluorescence signal, cell viability is compromised when the gating and sampling frequencies are equal (or effectively one bunch-pulse per pixel). We found an optimum gating frequency range that maintains the viability of the cells while preserving a pre-set fluorescence signal of the acquired two-photon images. The neurons are imaged while under whole-cell patch, and the cell viability is monitored as a change in the membrane's input resistance. PMID:26504651

  19. Effects of ELF fields on calcium-ion efflux from brain tissues in vitro

    International Nuclear Information System (INIS)

    It has been previously demonstrated that carrier waves of 50 and 147 MHz, when sinusoidally amplitude modulated at 16 Hz (ELF), can cause enhanced efflux of radiolabeled calcium ions from chick brain tissue in vitro. This phenomenon occurs only when the samples are exposed to specific intensity ranges of the carrier wave. Unmodulated carrier waves do not affect the ion efflux. Since the ELF signal must be demodulated from the carrier wave to be effective, a study of the efflux ehnancement due to the ELF signal alone may lead to an identification of the site of demodulation, as well as provide clues to the underlying mechanism. We report here that 16-Hz sinusoidal fields in the absence of a carrier wave can alter the efflux rate of calcium ions. The results show a frequency-dependent, field-induced enhancement of calcium-ion efflux within the ranges 5 to 7.5 V/m and 35 to 50 V/m (peak-to-peak incident field in air) with no enhancement within the ranges 1 to 2, 10 to 30, and 60 to 70 V/m

  20. Magnetization transfer studies of the fast and slow tissue water diffusion components in the human brain.

    Science.gov (United States)

    Mulkern, Robert V; Vajapeyam, Sridhar; Haker, Steven J; Maier, Stephan E

    2005-05-01

    Magnetization transfer (MT) properties of the fast and slow diffusion components recently observed in the human brain were assessed experimentally. One set of experiments, performed at 1.5 T in healthy volunteers, was designed to determine whether the amplitudes of fast and slow diffusion components, differentiated on the basis of biexponential fits to signal decays over a wide range of b-factors, demonstrated a different or similar magnetization transfer ratio (MTR). Another set of experiments, performed at 3 T in healthy volunteers, was designed to determine whether MTRs differed when measured from high signal-to-noise images acquired with b-factor weightings of 350 vs 3500 s/mm2. The 3 T studies included measurements of MTR as a function of off-resonance frequency for the MT pulse at both low and high b-factors. The primary conclusion drawn from all the studies is that there appears to be no significant difference between the magnetization transfer properties of the fast and slow tissue water diffusion components. The conclusions do not lend support to a direct interpretation of the 'components' of the biexponential diffusion decay in terms of the 'compartments' associated with intra- and extracellular water. PMID:15578729

  1. Multimodal Raman-fluorescence spectroscopy of formalin fixed samples is able to discriminate brain tumors from dysplastic tissue

    Science.gov (United States)

    Anand, Suresh; Cicchi, Riccardo; Giordano, Flavio; Buccoliero, Anna Maria; Pavone, Francesco Saverio

    2014-05-01

    In the recent years, there has been a considerable surge in the application of spectroscopy for disease diagnosis. Raman and fluorescence spectra provide characteristic spectral profile related to biochemical and morphological changes when tissues progress from normal state towards malignancy. Spectroscopic techniques offer the advantage of being minimally invasive compared to traditional histopathology, real time and quantitative. In biomedical optical diagnostics, freshly excised specimens are preferred for making ex-vivo spectroscopic measurements. With regard to fresh tissues, if the lab is located far away from the clinic it could pose a problem as spectral measurements have to be performed immediately after dissection. Tissue samples are usually placed in a fixative agent such as 4% formaldehyde to preserve the samples before processing them for routine histopathological studies. Fixation prevents the tissues from decomposition by arresting autolysis. In the present study, we intend to investigate the possibility of using formalin fixed samples for discrimination of brain tumours from dysplastic tissue using Raman and fluorescence spectroscopy. Formalin fixed samples were washed with phosphate buffered saline for about 5 minutes in order to remove the effects of formalin during spectroscopic measurements. In case of fluorescence spectroscopy, changes in spectral profile have been observed in the region between 550-670 nm between dysplastic and tumor samples. For Raman measurements, we found significant differences in the spectral profiles between dysplasia and tumor. In conclusion, formalin fixed samples can be potentially used for the spectroscopic discrimination of tumor against dysplastic tissue in brain samples.

  2. Heart and Brain Tissue Banks for Research on Co-Occurring Cardiovascular and Neurological/Psychiatric Disorders

    Directory of Open Access Journals (Sweden)

    Milos D. Ikonomovic

    2009-01-01

    Full Text Available Epidemiological studies point to a strong and possibly causal association of psychiatric and neurological disorders with cardiovascular disease (CVD. Mechanistic links between these co-occurring illnesses are not well understood. Better insight into their relationship could help identify novel diagnostic markers and therapeutic targets. For successful translation of basic biomedical research into clinical practice, analyses of postmortem human tissues are essential. However, current tissue banks dedicated to psychiatric and neurological research collect only brain tissue samples deemed most important to the institution's participating investigators. While this practice is often dictated by budget constraints, restricted tissue storage space and other practical reasons, it limits the ability of the biological research community to access and study multiple organ systems relevant to cardiovascular and neuronal systems dysfunction. This problem is worsened when clinical records pertaining to coexistent systemic pathology are not available. To promote further understanding of co-occurring CVD and psychiatric/neurological disorders, efforts should be made to support tissue banks that harvest heart, coronary arteries, and aorta samples as well as brain tissue, from the same subjects.

  3. The quantitative analysis of S100 in the brain tissue and serum following diffuse brain injury in rats

    Institute of Scientific and Technical Information of China (English)

    Wang Qi; Huang Ping; Xing Bo; Tuo Ya; Zhang Yongpan; Tian Weiping; Wang Zhenyuan

    2007-01-01

    Objective To investigate the dynamics of the level of S100 in cerebrum, brainstem, and serum following the diffuse brain injury in rats and provide the experimental evidences for estimating injury time. Methods ELISA was used to determine whether S100 protein is changed after diffuse brain injury in rats. Forty rats were sacrificed at 0.5 hour, 2 hours, 4 hours, 12 hours, 24 hours, 3 d and 7 d after diffuse brain injury and normal rats as control. Results The level of S100 in cerebrum, brainstem, and serum increased, followed by a decrease, and then further increased. The level of S100 could be detected to increase at 30 minutes and reached the peak at 4 hours after DBI. The level decreased gradually to the normal at 1d and till 3 d formed the second peak. The level returned to the normal at 7d following injury again. In the postmortem injury groups, there were no significant changes compared to the control group. Conclusion The present study showed that the time-dependent expression of S100 is obvious following diffuse brain injury in rats and suggested that S100 will be a suitable marker for diffuse brain injury age determination.

  4. Delayed contrast extravasation MRI for depicting tumor and non-tumoral tissues in primary and metastatic brain tumors.

    Directory of Open Access Journals (Sweden)

    Leor Zach

    Full Text Available The current standard of care for newly diagnosed glioblastoma multiforme (GBM is resection followed by radiotherapy with concomitant and adjuvant temozolomide. Recent studies suggest that nearly half of the patients with early radiological deterioration post treatment do not suffer from tumor recurrence but from pseudoprogression. Similarly, a significant number of patients with brain metastases suffer from radiation necrosis following radiation treatments. Conventional MRI is currently unable to differentiate tumor progression from treatment-induced effects. The ability to clearly differentiate tumor from non-tumoral tissues is crucial for appropriate patient management. Ten patients with primary brain tumors and 10 patients with brain metastases were scanned by delayed contrast extravasation MRI prior to surgery. Enhancement subtraction maps calculated from high resolution MR images acquired up to 75 min after contrast administration were used for obtaining stereotactic biopsies. Histological assessment was then compared with the pre-surgical calculated maps. In addition, the application of our maps for prediction of progression was studied in a small cohort of 13 newly diagnosed GBM patients undergoing standard chemoradiation and followed up to 19.7 months post therapy. The maps showed two primary enhancement populations: the slow population where contrast clearance from the tissue was slower than contrast accumulation and the fast population where clearance was faster than accumulation. Comparison with histology confirmed the fast population to consist of morphologically active tumor and the slow population to consist of non-tumoral tissues. Our maps demonstrated significant correlation with perfusion-weighted MR data acquired simultaneously, although contradicting examples were shown. Preliminary results suggest that early changes in the fast volumes may serve as a predictor for time to progression. These preliminary results suggest that

  5. A Hybrid DE-RGSO-ELM for Brain Tumor Tissue Categorization in 3D Magnetic Resonance Images

    Directory of Open Access Journals (Sweden)

    K. Kothavari

    2014-01-01

    Full Text Available Medical diagnostics, a technique used for visualizing the internal structures and functions of human body, serves as a scientific tool to assist physicians and involves direct use of digital imaging system analysis. In this scenario, identification of brain tumors is complex in the diagnostic process. Magnetic resonance imaging (MRI technique is noted to best assist tissue contrast for anatomical details and also carries out mechanisms for investigating the brain by functional imaging in tumor predictions. Considering 3D MRI model, analyzing the anatomy features and tissue characteristics of brain tumor is complex in nature. Henceforth, in this work, feature extraction is carried out by computing 3D gray-level cooccurence matrix (3D GLCM and run-length matrix (RLM and feature subselection for dimensionality reduction is performed with basic differential evolution (DE algorithm. Classification is performed using proposed extreme learning machine (ELM, with refined group search optimizer (RGSO technique, to select the best parameters for better simplification and training of the classifier for brain tissue and tumor characterization as white matter (WM, gray matter (GM, cerebrospinal fluid (CSF, and tumor. Extreme learning machine outperforms the standard binary linear SVM and BPN for medical image classifier and proves better in classifying healthy and tumor tissues. The comparison between the algorithms proves that the mean and standard deviation produced by volumetric feature extraction analysis are higher than the other approaches. The proposed work is designed for pathological brain tumor classification and for 3D MRI tumor image segmentation. The proposed approaches are applied for real time datasets and benchmark datasets taken from dataset repositories.

  6. Comparative support for the expensive tissue hypothesis: Big brains are correlated with smaller gut and greater parental investment in Lake Tanganyika cichlids

    OpenAIRE

    Tsuboi, Masahito; Husby, Arild; Kotrschal, Alexander; Hayward, Alexander; Buechel, Severine D.; Zidar, Josefina; Løvlie, Hanne; Kolm, Niclas

    2014-01-01

    The brain is one of the most energetically expensive organs in the vertebrate body. Consequently, the energetic requirementsof encephalization are suggested to impose considerable constraints on brain size evolution. Three main hypotheses concerninghow energetic constraints might affect brain evolution predict covariation between brain investment and (1) investment intoother costly tissues, (2) overall metabolic rate, and (3) reproductive investment. To date, these hypotheses have mainly been...

  7. Comparison of regional skeletal muscle tissue oxygenation in college athletes and sedentary control subjects using quantitative BOLD MR imaging.

    Science.gov (United States)

    Stacy, Mitchel R; Caracciolo, Christopher M; Qiu, Maolin; Pal, Prasanta; Varga, Tyler; Constable, Robert Todd; Sinusas, Albert J

    2016-08-01

    Blood oxygen level-dependent (BOLD) magnetic resonance (MR) imaging permits noninvasive assessment of tissue oxygenation. We hypothesized that BOLD imaging would allow for regional evaluation of differences in skeletal muscle oxygenation between athletes and sedentary control subjects, and dynamic BOLD responses to ischemia (i.e., proximal cuff occlusion) and reactive hyperemia (i.e., rapid cuff deflation) would relate to lower extremity function, as assessed by jumping ability. College football athletes (linemen, defensive backs/wide receivers) were compared to sedentary healthy controls. BOLD signal of the gastrocnemius, soleus, anterior tibialis, and peroneus longus was assessed for peak hyperemic value (PHV), time to peak (TTP), minimum ischemic value (MIV), and time to recovery (TTR). Significantly higher PHVs were identified in athletes versus controls for the gastrocnemius (linemen, 15.8 ± 9.1%; defensive backs/wide receivers, 17.9 ± 5.1%; controls, 7.4 ± 3.5%), soleus (linemen, 25.9 ± 11.5%; backs/receivers, 22.0 ± 9.4%; controls, 12.9 ± 5.8%), and anterior tibialis (linemen, 12.8 ± 5.3%; backs/receivers, 12.6 ± 3.9%; controls, 7.7 ± 4.0%), whereas no differences in PHV were found for the peroneus longus (linemen, 14.1 ± 6.9%; backs/receivers, 11.7 ± 4.6%; controls, 9.0 ± 4.9%). In all subject groups, the gastrocnemius and soleus muscles exhibited the lowest MIVs during cuff occlusion. No differences in TTR were found between muscles for any subject group. PHV of the gastrocnemius muscle was significantly and positively related to maximal vertical (r = 0.56, P = 0.002) and broad jump (r = 0.47, P = 0.01). These results suggest that BOLD MR imaging is a useful noninvasive tool for evaluating differences in tissue oxygenation of specific muscles between active and sedentary individuals, and peak BOLD responses may relate to functional capacity. PMID:27535483

  8. c-Src and neural Wiskott-Aldrich syndrome protein (N-WASP promote low oxygen-induced accelerated brain invasion by gliomas.

    Directory of Open Access Journals (Sweden)

    Zhuo Tang

    Full Text Available Malignant gliomas remain associated with poor prognosis and high morbidity because of their ability to invade the brain; furthermore, human gliomas exhibit a phenotype of accelerated brain invasion in response to anti-angiogenic drugs. Here, we study 8 human glioblastoma cell lines; U251, U87, D54 and LN229 show accelerated motility in low ambient oxygen. Src inhibition by Dasatinib abrogates this phenotype. Molecular discovery and validation studies evaluate 46 molecules related to motility or the src pathway in U251 cells. Demanding that the molecular changes induced by low ambient oxygen are reversed by Dasatinib in U251 cells, identifies neural Wiskott-Aldrich syndrome protein (NWASP, Focal adhesion Kinase (FAK, [Formula: see text]-Catenin, and Cofilin. However, only Src-mediated NWASP phosphorylation distinguishes the four cell lines that exhibit enhanced motility in low ambient oxygen. Downregulating c-Src or NWASP by RNA interference abrogates the low-oxygen-induced enhancement in motility by in vitro assays and in organotypic brain slice cultures. The findings support the idea that c-Src and NWASP play key roles in mediating the molecular pathogenesis of low oxygen-induced accelerated brain invasion by gliomas.

  9. c-Src and neural Wiskott-Aldrich syndrome protein (N-WASP) promote low oxygen-induced accelerated brain invasion by gliomas.

    Science.gov (United States)

    Tang, Zhuo; Araysi, Lita M; Fathallah-Shaykh, Hassan M

    2013-01-01

    Malignant gliomas remain associated with poor prognosis and high morbidity because of their ability to invade the brain; furthermore, human gliomas exhibit a phenotype of accelerated brain invasion in response to anti-angiogenic drugs. Here, we study 8 human glioblastoma cell lines; U251, U87, D54 and LN229 show accelerated motility in low ambient oxygen. Src inhibition by Dasatinib abrogates this phenotype. Molecular discovery and validation studies evaluate 46 molecules related to motility or the src pathway in U251 cells. Demanding that the molecular changes induced by low ambient oxygen are reversed by Dasatinib in U251 cells, identifies neural Wiskott-Aldrich syndrome protein (NWASP), Focal adhesion Kinase (FAK), [Formula: see text]-Catenin, and Cofilin. However, only Src-mediated NWASP phosphorylation distinguishes the four cell lines that exhibit enhanced motility in low ambient oxygen. Downregulating c-Src or NWASP by RNA interference abrogates the low-oxygen-induced enhancement in motility by in vitro assays and in organotypic brain slice cultures. The findings support the idea that c-Src and NWASP play key roles in mediating the molecular pathogenesis of low oxygen-induced accelerated brain invasion by gliomas.

  10. Hypoxia inducible factor-1alpha mediates protection of DL-3-n-butylphthalide in brain microvascular endothelial cells against oxygen glucose deprivation-induced injury

    Institute of Scientific and Technical Information of China (English)

    Weihong Yang; Ling Li; Ruxun Huang; Zhong Pei; Songjie Liao; Jinsheng Zeng

    2012-01-01

    Studies have demonstrated that DL-3-n-butylphthalide can significantly alleviate oxygen glucose deprivation-induced injury of human umbilical vein endothelial cells at least partly associated with its enhancement on oxygen glucose deprivation -induced hypoxia inducible factor-1α expression. In this study, we hypothesized that DL-3-n-butylphthalide can protect against oxygen glucose deprivation-induced injury of newborn rat brain microvascular endothelial cells by means of upregulating hypoxia inducible factor-1α expression. MTT assay and Hoechst staining results showed that DL-3-n-butylphthalide protected brain microvascular endothelial cells against oxygen glucose deprivation-induced injury in a dose-dependent manner. Western blot and immunofluorescent staining results further confirmed that the protective effect was related to upregulation of hypoxia inducible factor-1α. Real-time RT-PCR reaction results showed that DL-3-n-butylphthalide reduced apoptosis by inhibiting downregulation of pro-apoptotic gene caspase-3 mRNA expression and upregulation of apoptosis-executive protease bcl-2 mRNA expression; however, DL-3-n-butylphthalide had no protective effects on brain microvascular endothelial cells after knockdown of hypoxia inducible factor-1α by small interfering RNA. These findings suggest that DL-3-n-butylphthalide can protect brain microvascular endothelial cells against oxygen glucose deprivation-induced injury by upregulating bcl-2 expression and downregulating caspase-3 expression though hypoxia inducible factor-1α pathway.

  11. Reduced muscle activation during exercise related to brain oxygenation and metabolism in humans

    DEFF Research Database (Denmark)

    Rasmussen, P; Nielsen, J; Overgaard, M;

    2010-01-01

    Maximal exercise may be limited by central fatigue defined as an inability of the central nervous system to fully recruit the involved muscles. This study evaluated whether a reduction in the cerebral oxygen-to-carbohydrate index (OCI) and in the cerebral mitochondrial oxygen tension relate...... to the ability to generate a maximal voluntary contraction and to the transcranial magnetic stimulated force generation. To determine the role of a reduced OCI and in central fatigue, 16 males performed low intensity, maximal intensity and hypoxic cycling exercise. Exercise fatigue was evaluated by ratings...... of perceived exertion (RPE), arm maximal voluntary force (MVC), and voluntary activation of elbow flexor muscles assessed with transcranial magnetic stimulation. Low intensity exercise did not produce any indication of central fatigue or marked cerebral metabolic deviations. Exercise in hypoxia (0.10) reduced...

  12. Quantitative analysis of sodium fast and slow component in in vivo human brain tissue using MR Na image

    Energy Technology Data Exchange (ETDEWEB)

    Hirai, Hirokazu; Yamasaki, Katsuhito; Kidena, Hitoshi; Kono, Michio (Kobe Univ. (Japan). School of Medicine)

    1992-12-01

    In vivo sodium concentrations in the normal brain tissue and a tumorous tissue were analyzed using MR Na image. The nuclear magnetic resonance enabled us to divide the signal from sodium in the living tissue into 2 parts based on the differences of T[sub 2] value. Those are fast component having the T[sub 2] value of less than 5 msec and slow component of 15-40 msec. We investigated the effect of macromolecules on T[sub 2] value of sodium image using polyvinylalcohol (PVA) powder. MR Na image was taken with the parameters of TR/TD, 110 ms/1.9 ms (FID image) and TR/TE, 110 ms/20 ms (SE image). Saline solution showed high intensity on both FID image and SE image. Saline solution added PVA (PVA phantom) also showed high intensity on FID image, whereas the signal intensity of PVA phantom in SE image extinguished. To know the relation between the signal intensity and sodium concentration, sodium concentration-signal intensity curve was obtained using phantoms with various sodium concentrations (0.05-1.0%). This curve showed a direct proportion between sodium concentration and signal intensity on Na image. We measured further the sodium concentrations of the human brain tissue. Sodium phantoms were arranged around the heads and the MR Na images of the normal brains from 3 volunteers and a patient with a brain tumor (meningioma) were taken. The sodium concentrations of occipital lobe, basal ganglia and the tumorous tissue were calculated using the sodium concentration-signal intensity curve obtained from the phantoms arranged around the heads. Two tailed t-test shows significant differences (p<0.01) in total sodium and slow component between occipital lobe and basal ganglia. Further more high concentration of fast component in tumorous tissue was observed. As fast component reflects the intracellular condition, present experiments suggest that measurement of fast component may be useful for obtaining the functional information of the brain tissue. (author).

  13. Variations of brain edema and neurological function of rat models of cerebral infarction after hyperbaric oxygen therapy%高压氧干预脑梗死模型大鼠脑水肿及神经功能变化

    Institute of Scientific and Technical Information of China (English)

    田烜

    2015-01-01

    背景:研究认为,高压氧有较好保护脑神经和脑细胞的作用,应用高压氧可使氧分压快速弥撒到相对缺氧的脑组织中,增加脑组织的血氧含量,促进脑水肿及脑神经功能的恢复。目的:观察大脑中动脉阻塞造模后高压氧干预对大鼠脑梗死组织水肿的影响,并探讨其对脑梗死大鼠神经功能保护的可能作用机制。方法:成年雌性SD大鼠65只,造模成功60只,随机区组法分为假手术组、脑梗死组、高压氧组,每组20只,按照线栓线法建立大鼠大脑中动脉阻塞脑梗死模型。造模后3 d,通过TUNEL法检测各实验组大鼠脑梗死区神经细胞的凋亡情况。伤后72 h通过RT-PCR、Western blot检测脑梗死区周围AQP4/9、基质金属蛋白酶9/2基因转录和蛋白的表达,通过苏木精-伊红染色观察脑梗死区病理组织形态学变化,通过免疫组织化学法检测胶质纤维酸性蛋白的表达量,高压氧干预后24 h,3 d及伤后1、2周行Longa行为学评分,检测神经功能的损伤情况。结果与结论:①高压氧组Longa行为学评分在治疗后1,2 d均较脑梗死组显著降低(P <0.05)。②造模后3 d高压氧组细胞凋亡指数均明显低于脑梗死组(P<0.05)。③造模后72 h,与脑梗死组相比高压氧组AQP4/9、基质金属蛋白酶9/2基因和蛋白表达均较显著降低(P<0.05)。结果提示高压氧治疗通过减少大鼠脑梗死区神经细胞的凋亡和降低脑组织水肿,对脑梗死起到保护作用。%BACKGROUND:Several studies have suggested that hyperbaric oxygen could better protect cranial nerve and brain cels. Hyperbaric oxygen therapy can make oxygen partial pressure rapidly diffusing toward relatively hypoxic brain tissue, so as to increase blood oxygen content in the brain tissue, reduce brain edema and promote the recovery of brain function. OBJECTIVE: To observe the effects of hyperbaric oxygen therapy on brain tissue

  14. Cell and brain tissue imaging of the flavonoid fisetin using label-free two-photon microscopy.

    Science.gov (United States)

    Krasieva, Tatiana B; Ehren, Jennifer; O'Sullivan, Thomas; Tromberg, Bruce J; Maher, Pamela

    2015-10-01

    Over the last few years, we have identified an orally active, novel neuroprotective and cognition-enhancing molecule, the flavonoid fisetin. Fisetin not only has direct antioxidant activity but it can also increase the intracellular levels of glutathione, the major intracellular antioxidant. Fisetin can also activate key neurotrophic factor signaling pathways. In addition, it has anti-inflammatory activity against microglia and astrocytes and inhibits the activity of lipoxygenases, thereby reducing the production of pro-inflammatory eicosanoids and their by-products. However, key questions about its targets and brain penetration remain. In this study, we used label-free two-photon microscopy of intrinsic fisetin fluorescence to examine the localization of fisetin in living nerve cells and the brains of living mice. In cells, fisetin but not structurally related flavonols with different numbers of hydroxyl groups, localized to the nucleoli suggesting that key targets of fisetin may reside in this organelle. In the mouse brain, following intraperitoneal injection and oral administration, fisetin rapidly distributed to the blood vessels of the brain followed by a slower dispersion into the brain parenchyma. Thus, these results provide further support for the effects of fisetin on brain function. In addition, they suggest that label-free two-photon microscopy may prove useful for studying the intracellular and tissue distribution of other intrinsically-fluorescent flavonoids.

  15. Covalent binding of formalin fixed paraffin embedded brain tissue sections to glass slides suitable for in situ hybridization.

    Science.gov (United States)

    Tourtellotte, W W; Verity, A N; Schmid, P; Martinez, S; Shapshak, P

    1987-02-01

    A novel method for covalently binding formalin fixed paraffin embedded (FFPE) tissue sections to glass microscope slides is validated suitable for in situ hybridization (ISH). Using the organosilane methodology of Maples (1985), 100% tissue adhesion is reported with no nonspecific probe binding, staining, or autoradiographic artefacts. JC viral nucleic acid sequences are successfully detected in FFPE progressive multifocal leukoencephalopathy brain tissue and the Tm of the hybridized product is estimated. From the Tm the most stringent washing condition resulting in an optimal signal to noise ratio is determined. A comparison is made between currently used methods of tissue adhesion and the proposed organosilane methodology. This methodology greatly facilitates studies of conditions for ISH and elucidation of mechanisms of viral infections requiring consecutive FFPE sections. It is also applicable to studies using cryosections and cultured cells.

  16. Trends in brain oxygenation during mental and physical exercise measured using near-infrared spectroscopy (NIRS): potential for early detection of Alzheimer's disease

    Science.gov (United States)

    Allen, Monica S.; Allen, Jeffery W.; Mikkilineni, Shweta; Liu, Hanli

    2005-04-01

    Motivation: Early diagnosis of Alzheimer's disease (AD) is crucial because symptoms respond best to available treatments in the initial stages of the disease. Recent studies have shown that marked changes in brain oxygenation during mental and physical tasks can be used for noninvasive functional brain imaging to detect Alzheimer"s disease. The goal of our study is to explore the possibility of using near infrared spectroscopy (NIRS) and mapping (NIRM) as a diagnostic tool for AD before the onset of significant morphological changes in the brain. Methods: A 16-channel NIRS brain imager was used to noninvasively measure spatial and temporal changes in cerebral hemodynamics induced during verbal fluency task and physical activity. The experiments involved healthy subjects (n = 10) in the age range of 25+/-5 years. The NIRS signals were taken from the subjects' prefrontal cortex during the activities. Results and Conclusion: Trends of oxygenated and deoxygenated hemoglobin in the prefrontal cortex of the brain were observed. During the mental stimulation, the subjects showed significant increase in oxygenated hemoglobin [HbO2] with a simultaneous decrease in deoxygenated hemoglobin [Hb]. However, physical exercise caused a rise in levels of HbO2 with small variations in Hb. This study basically demonstrates that NIRM taken from the prefrontal cortex of the human brain is sensitive to both mental and physical tasks and holds potential to serve as a diagnostic means for early detection of Alzheimer's disease.

  17. Titanium dioxide (P25) produces reactive oxygen species in immortalized brain microglia (BV2): implications for nanoparticle neurotoxicity.

    Science.gov (United States)

    Long, Thomas C; Saleh, Navid; Tilton, Robert D; Lowry, Gregory V; Veronesi, Bellina

    2006-07-15

    Concerns with the environmental and health risk of widely distributed, commonly used nanoparticles are increasing. Nanosize titanium dioxide (TiO2) is used in air and water remediation and in numerous products designed for direct human use and consumption. Its effectiveness in deactivating pollutants and killing microorganisms relates to photoactivation and the resulting free radical activity. This property, coupled with its multiple potential exposure routes, indicates that nanosize TiO2 could pose a risk to biological targets that are sensitive to oxidative stress damage (e.g., brain). In this study, brain microglia (BV2) were exposed to a physicochemically characterized (i.e., dispersion stability, particle size distribution, and zeta potential) nanomaterial, Degussa P25, and cellular expressions of reactive oxygen species were measured with fluorescent probes. P25's zeta potentials, measured in cell culture media and physiological buffer were -11.6 +/- 1.2 mV and -9.25 +/- 0.73 mV, respectively. P25 aggregation was rapid in both media and buffer with the hydrodynamic diameter of stable P25 aggregates ranging from 826 nm to 2368 nm depending on the concentration. The biological response of BV2 microglia to noncytotoxic (2.5-120 ppm) concentrations of P25 was a rapid (<5 min) and sustained (120 min) release of reactive oxygen species. The time course of this release suggested that P25 not only stimulated the immediate "oxidative burst" response in microglia but also interfered with mitochondrial energy production. Transmission electron microscopy indicated that small groups of nanosized particles and micron-sized aggregates were engulfed bythe microglia and sequestered as intracytoplasmic aggregates after 6 and 18 h exposure to P25 (2.5 ppm). Cell viability was maintained at all test concentrations (2.5-120 ppm) over the 18 h exposure period. These data indicate that mouse microglia respond to Degussa P25 with cellular and morphological expressions of free

  18. Effects of cadmium and copper on sialic acid levels in blood and brain tissues of Cyprinus carpio L.

    Institute of Scientific and Technical Information of China (English)

    Utku Gner; Elvan Bakar

    2014-01-01

    Objective: To investigate the effects of cadmium (Cd) and copper (Cu) on sialic acid levels of brain and blood tissues of Cyprinus carpio.Methods:Adult carps were exposed to 0.1, 0.5 mg/L Cu, 0.1, 0.5 and 1.0 mg/L Cd and 0.1 mg/L Cu+0.1 mg/L Cd under static experiment conditions for 1 week. At the end of exposure period, heavy metal accumulations and sialic acid levels in blood and brain tissues of the test animals were analyzed.Results:Cu and Cd accumulated in tissues in a dramatically increasing dose-dependent manner. Sialic acids level of the fish exposed to 0.1, 0.5 and 1.0 mg/L Cu and Cd and control grups for 1 week were 0.834, 1.427, 0.672, 0.934, 2.968, 4.714 mg/mL respectively. The results also showed that Cu has an antagonistic effect on tissue sialic acid level.Conclusions:We propose that Cd and Cu make a complex with sialic acids of membranes in the tissues researched. This complex between metal ions and sialic acid migth account for the cellular toxicity based on Cu and Cd.

  19. Hyperbaric oxygen therapy in the treatment of radio-induced lesions in normal tissues: a literature review

    International Nuclear Information System (INIS)

    Late complications are one of the major factors limiting radiotherapy treatment, and their treatment is not codified. Hyperbaric oxygen (HBO) has been used in combination with radiotherapy for over half a century, either to maximise its effectiveness or in an attempt to treat late complications. In this latter case, retrospective trials and case reports are prevailing in literature. This prompted European Society for Therapeutic Radiotherapy and Oncology and European Committee for Hyperbaric Medicine to organise a consensus conference in October 2001, dealing with the HBO indications on radiotherapy for the treatment and prevention of late complications. This updated literature review is part of the documents the jury based its opinion on. A systematic search was done on literature from 1960 to 2004, by only taking into account the articles that appeared in peer review journals. Hyperbaric oxygen treatment involving complications to the head and neck, pelvis and nervous system, and the prevention of complications after surgery in irradiated tissues have been studied. Despite the small number of controlled trials, it may be indicated for the treatment of mandibular osteoradionecrosis in combination with surgery, haemorrhagic cystitis resistant to conventional treatments and the prevention of osteoradionecrosis after dental extraction, whose level of evidence seems to be the most significant though randomised trials are still necessary. The other treatment methods are also outlined for each location

  20. Model-based cell number quantification using online single-oxygen sensor data for tissue engineering perfusion bioreactors.

    Science.gov (United States)

    Lambrechts, T; Papantoniou, I; Sonnaert, M; Schrooten, J; Aerts, J-M

    2014-10-01

    Online and non-invasive quantification of critical tissue engineering (TE) construct quality attributes in TE bioreactors is indispensable for the cost-effective up-scaling and automation of cellular construct manufacturing. However, appropriate monitoring techniques for cellular constructs in bioreactors are still lacking. This study presents a generic and robust approach to determine cell number and metabolic activity of cell-based TE constructs in perfusion bioreactors based on single oxygen sensor data in dynamic perfusion conditions. A data-based mechanistic modeling technique was used that is able to correlate the number of cells within the scaffold (R(2)  = 0.80) and the metabolic activity of the cells (R(2)  = 0.82) to the dynamics of the oxygen response to step changes in the perfusion rate. This generic non-destructive measurement technique is effective for a large range of cells, from as low as 1.0 × 10(5) cells to potentially multiple millions of cells, and can open-up new possibilities for effective bioprocess monitoring.

  1. Expression of EF-Tumt and EF-Tsmt in brain tissues of patients with mesial temporal lobe epilepsy

    Institute of Scientific and Technical Information of China (English)

    Jun Lu; Qi-Chang Zeng; Qin Wang; Ya-Hui Huang; Qiong Peng

    2016-01-01

    Objective:To explore the expression of EF-Tumt and EF-Tsmt in brain tissue of patients with mesial temporal lobe epilepsy (MTLE). Methods:From January 2013 to January 2015, a total of 62 patients with MTLE who were treated with anterior temporal lobe resection in the Department of neurosurgery in Hunan Brain Hospital were selected and classified as the case group, at the same time, 48 patients with brain trauma were chosen and considered to be the control group. The expression of EF-Tumt and EF-Tsmt was detected and compared between the two groups. Results:EF-Tumt positive particles and EF-Tsmt positive particles were noticed in the mitochondria and cytoplasm of brain tissues of the medial temporal lobe in the two groups by election microscopic observation, and the number of the two types of positive particles in the case group was significantly more than that in the control group (P<0.05);similarly, EF-Tumt positive cells and EF-Tsmt positive cells were also observed in the neurons and astrocytes of brain tissues of the medial temporal lobe in the two groups by election microscopic observation, and the number of the above-mentioned positive cells in the case group was also significantly larger than that in the control group (P<0.05). Conclusions:The expression intensities of EF-Tsmt and EF-Tumt in patients with MTLE are higher than these in patients without epilepsy. Therefore, EF-Tsmt and EF-Tumt play important roles in MTLE.

  2. Fatty acid composition of total lipids and phospholipids of muscular tissue and brain of rats under the impact of vibration

    Directory of Open Access Journals (Sweden)

    N. M. Kostyshyn

    2016-06-01

    Full Text Available Fatty acids are important structural components of biological membranes, energy substrate of cells involved in fixing phospholipid bilayer proteins, and acting as regulators and modulators of enzymatic activity. Under the impact of vibration oscillations there can occur shifts in the ratio of different groups of fatty acids, and degrees of their saturation may change. The imbalance between saturated, monounsaturated and polyunsaturated fatty acids, which occurs later in the cell wall, disrupts fluidity and viscosity of lipid phase and causes abnormal cellular metabolism. Aim. In order to study the impact of vibration on the level of fatty acids of total lipids in muscular tissue and fatty acid composition of phospholipids in muscles and brain, experimental animals have been exposed to vertical vibration oscillations with different frequency for 28 days. Methods and results. Tissues fragments of hip quadriceps and brain of rats were used for obtaining methyl esters of fatty acids studied by the method of gas-liquid chromatography. It was found that the lipid content, ratio of its separate factions and fatty acid composition in muscular tissue and brain of animals with the action of vibration considerably varies. With the increase of vibration acceleration tendency to increase in absolute quantity of total lipids fatty acids can be observed at the account of increased level of saturated and monounsaturated ones. These processes are caused by activation of self-defense mechanisms of the body under the conditions of deviations from stabilized physiological norm, since adaptation requires certain structural and energy costs. Increase in the relative quantity of saturated and monounsaturated fatty acids in phospholipids of muscles and brain and simultaneous reduction in concentration of polyunsaturated fatty acids are observed. Conclusion. These changes indicate worsening of structural and functional organization of muscles and brain cell membranes of

  3. Differences in supratentorial white matter diffusion after radiotherapy - New biomarker of normal brain tissue damage?

    Energy Technology Data Exchange (ETDEWEB)

    Ravn, Soeren; Jens Broendum Froekaer, Jens [Dept. of Radiology, Aalborg Univ. Hospital, Aalborg (Denmark)], e-mail: sorl@rn.dk; Holmberg, Mats [Dept. of Oncology, Aalborg Univ. Hospital, Aalborg (Denmark); Soerensen, Preben [Dept. of Neurosurgery, Aalborg Univ. Hospital, Aalborg (Denmark); Carl, Jesper [Dept. of Neurosurgery, Aalborg Univ. Hospital, Aalborg (Denmark)

    2013-10-15

    Introduction: Therapy-induced injury to normal brain tissue is a concern in the treatment of all types of brain tumours. The purpose of this study was to investigate if magnetic resonance diffusion tensor imaging (DTI) could serve as a potential biomarker for the assessment of radiation-induced long-term white matter injury. Material and methods: DTI- and T1-weighted images of the brain were obtained in 19 former radiotherapy patients [nine men and 10 women diagnosed with astrocytoma (4), pituitary adenoma (6), meningioma (8) and craniopharyngioma (1), average age 57.8 (range 35-71) years]. Average time from radiotherapy to DTI scan was 4.6 (range 2.0-7.1) years. NordicICE software (NIC) was used to calculate apparent diffusion coefficient maps (ADC-maps). The co-registration between T1 images and ADC-maps were done using the auto function in NIC. The co-registration between the T1 images and the patient dose plans were done using the auto function in the treatment planning system Eclipse from Varian. Regions of interest were drawn on the T1-weighted images in NIC based on iso curves from Eclipse. Data was analysed by t-test. Estimates are given with 95 % CI. Results: A mean ADC difference of 4.6(0.3;8.9) X 10{sup -5} mm{sup 2}/s, p = 0.03 was found between paired white matter structures with a mean dose difference of 31.4 Gy. Comparing the ADC-values of the areas with highest dose from the paired data (dose > 33 Gy) with normal white matter (dose < 5 Gy) resulted in a mean dose difference of 44.1 Gy and a mean ADC difference of 7.87(3.15;12.60) X 10{sup -5} mm{sup 2}/s, p = 0.003. Following results were obtained when looking at differences between white matter mean ADC in average dose levels from 5 to 55 Gy in steps of 10 Gy with normal white matter mean ADC: 5 Gy; 1.91(-1.76;5.58) X 10{sup -5} mm{sup 2}/s, p = 0.29; 15 Gy; 5.81(1.53;10.11) X 10{sup -5} mm{sup 2}/s, p = 0.01; 25 Gy; 5.80(2.43;9.18) X 10{sup -5} mm{sup 2}/s, p = 0.002; 35 Gy; 5.93(2.89;8.97) X 10

  4. Average blood flow and oxygen uptake in the human brain during resting wakefulness

    DEFF Research Database (Denmark)

    Madsen, P L; Holm, S; Herning, M;

    1993-01-01

    The Kety-Schmidt technique can be regarded as the reference method for measurement of global average cerebral blood flow (average CBF) and global average cerebral metabolic rate of oxygen (average CMRO2). However, in the practical application of the method, diffusion equilibrium for inert gas...... the measured data, we find that the true average values for CBF and CMRO2 in the healthy young adult are approximately 46 ml 100 g-1 min-1 and approximately 3.0 ml 100 g-1 min-1. Previous studies have suggested that some of the variation in CMRO2 values could be ascribed to differences in cerebral venous...

  5. HSF1 is essential for the resistance of zebrafish eye and brain tissues to hypoxia/reperfusion injury.

    Directory of Open Access Journals (Sweden)

    Nathan R Tucker

    Full Text Available Ischemia and subsequent reperfusion (IR produces injury to brain, eye and other tissues, contributing to the progression of important clinical pathologies. The response of cells to IR involves activation of several signaling pathways including those activating hypoxia and heat shock responsive transcription factors. However, specific roles of these responses in limiting cell damage and preventing cell death after IR have not been fully elucidated. Here, we have examined the role of heat shock factor 1 (HSF1 in the response of zebrafish embryos to hypoxia and subsequent return to normoxic conditions (HR as a model for IR. Heat shock preconditioning elevated heat shock protein expression and protected zebrafish embryo eye and brain tissues against HR-induced apoptosis. These effects were inhibited by translational suppression of HSF1 expression. Reduced expression of HSF1 also increased cell death in brain and eye tissues of embryos subjected to hypoxia and reperfusion without prior heat shock. Surprisingly, reduced expression of HSF1 had only a modest effect on hypoxia-induced expression of Hsp70 and no effect on hypoxia-induced expression of Hsp27. These results establish the zebrafish embryo as a model for the study of ischemic injury in the brain and eye and reveal a critical role for HSF1 in the response of these tissues to HR. Our results also uncouple the role of HSF1 expression from that of Hsp27, a well characterized heat shock protein considered essential for cell survival after hypoxia. Alternative roles for HSF1 are considered.

  6. AMP-activated protein kinase phosphorylation in brain is dependent on method of sacrifice and tissue preparation

    OpenAIRE

    Scharf, Matthew T.; Mackiewicz, Miroslaw; Naidoo, Nirinjini; O'Callaghan, James P.; Pack, Allan I.

    2007-01-01

    AMP-activated protein kinase is activated when the catalytic α subunit is phosphorylated on Thr172 and therefore, phosphorylation of the α subunit is used as a measure of activation. However, measurement of α-AMP-activated protein kinase phosphorylation in vivo can be technically challenging. To determine the most accurate method for measuring α-AMP-activated protein kinase phosphorylation in the mouse brain, we compared different methods of sacrifice and tissue preparation. We found that fre...

  7. Blood flow and vascular reactivity in collaterally perfused brain tissue. Evidence of an ischemic penumbra in patients with acute stroke

    DEFF Research Database (Denmark)

    Olsen, T S; Larsen, B; Herning, M;

    1983-01-01

    In a group of 48 patients with completed stroke, 8 patients had viable collaterally perfused brain tissue which was accessible for rCBF recordings with a two dimensional technique. All 8 had deep subcortical infarcts on CT-scan, and angiographic occlusion of the arteries normally supplying the in...... the experimental finding of an ischemic penumbra associated with acute cerebral infarcts and suggest that early restoration of the blood flow in acute stroke patients might improve recovery and prognosis in selected patients....

  8. Hyperbaric oxygen treatment induces dynamic ATPase activity changes in the rat brain following transient global cerebral ischemia-reperfusion

    Institute of Scientific and Technical Information of China (English)

    Shiming Xu; Hongjuan Wang; Tongnan Gu; Xiuyan Zhou; Rui Chen

    2008-01-01

    BACKGROUND: Energy depletion, induced by ischemia or hypoxia, is one of the first events in neuronal injury. OBJECTIVE: To investigate the dynamic changes of Na+-K+-ATPase and Ca2+-ATPase activity in the rat brain following transient global cerebral ischemia-reperfusion (IR), as well as the effects of hyperbaric oxygen (HBO) treatment. DESIGN, TIME AND SETTING: A randomized and controlled animal study was performed in the Department of Biochemistry and Molecular Biology, Capital Medical University between February and December 2006. MATERIALS: Clean-grade, female, Sprague Dawley rats were provided by the Animal Research Department of Capital Medical University (License number: SYXK11-00-0047). Na+-K+-ATPase and Ca2+-ATPase kits were provided by Nanjing Jiancheng Bioengineering Institute (Nanjing, China). A hyperbaric oxygen chamber (DWC150-300) was supplied by Shanghai 701 Medical Oxygen Chamber Factory (Shanghai, China). METHODS: Sixty-three rats were randomly divided into nine groups: sham operated group (sham-O) as control, groups of IR, and groups treated with hyperbaric oxygen (HBO) after IR. Animal from the IR and HBO groups were sacrificed after four different survival intervals of 6, 24, 48 and 96 hours, respectively. Each group consisted of seven rats. The rats of HBO groups were placed into the hyperbaric chamber. The HBO chamber was flushed with pure oxygen for 5 minutes, followed by a gradual rise in pressure over 5 minutes and stabilization at 0.2 MPa. Then, pure oxygen was supplied for 45 minutes in stabilized pressure, followed by gradually reduced pressure over 15 minutes. The rats of the 6-h HBO group were placed into the HBO chamber following reperfusion for 3 hours on the first day, which was repeated on three consecutive days, always at the same time. Rats in the sham-O group and IR group remained under normal atmospheric pressure. MAIN OUTCOME MEASURES: The Na+-K+-ATPase and Ca2+-ATPase activity in rat brain homogenate was detected by the

  9. Through metal binding, curcumin protects against lead- and cadmium-induced lipid peroxidation in rat brain homogenates and against lead-induced tissue damage in rat brain.

    Science.gov (United States)

    Daniel, Sheril; Limson, Janice L; Dairam, Amichand; Watkins, Gareth M; Daya, Santy

    2004-02-01

    Curcumin, the major constituent of turmeric is a known, naturally occurring antioxidant. The present study examined the ability of this compound to protect against lead-induced damage to hippocampal cells of male Wistar rats, as well as lipid peroxidation induced by lead and cadmium in rat brain homogenate. The thiobarbituric assay (TBA) was used to measure the extent of lipid peroxidation induced by lead and cadmium in rat brain homogenate. The results show that curcumin significantly protects against lipid peroxidation induced by both these toxic metals. Coronal brain sections of rats injected intraperitoneally with lead acetate (20 mg/kg) in the presence and absence of curcumin (30 mg/kg) were compared microscopically to determine the extent of lead-induced damage to the cells in the hippocampal CA1 and CA3 regions, and to establish the capacity of curcumin to prevent such damage. Lead-induced damage to the neurons was significantly curtailed in the rats injected with curcumin. Possible chelation of lead and cadmium by curcumin as its mechanism of neuroprotection against such heavy metal insult to the brain was investigated using electrochemical, ultraviolet spectrophotometric and infrared spectroscopic analyses. The results of the study show that there is an interaction between curcumin and both cadmium and lead, with the possible formation of a complex between the metal and this ligand. These results imply that curcumin could be used therapeutically to chelate these toxic metals, thus potentially reducing their neurotoxicity and tissue damage.

  10. Changes in hemeoxygenase-1 and superoxide dismutase in the peri-hematomal brain tissues of rats following intracerebral hemorrhage

    Institute of Scientific and Technical Information of China (English)

    Jiami Wu; Qingwei Meng

    2006-01-01

    BACKGROUND: The mechanism of intracerebral hemorrhage (ICH)-induced hemorrhagic brain injury is very complicated, involving the position-occupying effect of oephalophyma, ischemio factors, the toxic effect of hematoma components, the destruction of blood-brain barrier, etc. The expression and effect of hemeoxygenase-1 (HO-1) in the cerebrovascular disease has been paid close attention.OBJECTIVE: To observe the expression of HO-1 and change of superoxide dismutase (SOD) in the peri-hematomal brain tissue of rats following ICH.DESIGN: Randomized controlled animal experiment.SETTING: Department of Neurology, Yijishan Hospital Affiliated to Wannan Medical College.MATERIALS: Forty healthy male SD rats, of clean grade, weighing from 250 to 300 g, were provided by Qinglongshan Animal Farm of Nanjing. The involved 40 rats were randomized into sham-operation group (n=5) and ICH group (n =35), and ICH group was divided into 7 subgroups with 5 rats in each: ICH 6, 12, 24, 48, 72,100 and 168 hours groups. Rabbit anti-rat HO-1 immunohistochemial kit ( Boster Co., Ltd., Wuhan) and SOD kit (Jiancheng Bioengineering Institute, Nanjing)were used in this experiment.METHODS: This experiment was carried out in the Department of Neurology, Yijishan Hospital Affiliated to Wannan Medical College Between April and July 2005. In the ICH group: Autologous blood of rats was injected into the head of caudate nucleus to create ICH animal models. In the sham-operation group, the same amount of normal saline was injected into the head of caudate nucleus of rats. The brains of rats in each group were harvested at different time points. The hematoma-side brain tissue was cut open in the coronal plane taking hematomal region as center, and the posterior part was fixed with 100 g/L neutral formaldehyde. 100 mg brain tissue was taken from anterior part. The number of positive cells in HO-1 and SOD activity in peri-hematomal brain tissue at different time after ICH were detected by immunohistochemical

  11. Organotypic slice cultures from rat brain tissue: a new approach for Naegleria fowleri CNS infection in vitro.

    Science.gov (United States)

    Gianinazzi, C; Schild, M; Müller, N; Leib, S L; Simon, F; Nuñez, S; Joss, P; Gottstein, B

    2005-12-01

    The free-living amoeba Naegleria fowleri is the aetiological agent of primary amoebic meningoencephalitis (PAM), a disease leading to death in the vast majority of cases. In patients suffering from PAM, and in corresponding animal models, the brain undergoes a massive inflammatory response, followed by haemorrhage and severe tissue necrosis. Both, in vivo and in vitro models are currently being used to study PAM infection. However, animal models may pose ethical issues, are dependent upon availability of specific infrastructural facilities, and are time-consuming and costly. Conversely, cell cultures lack the complex organ-specific morphology found in vivo, and thus, findings obtained in vitro do not necessarily reflect the situation in vivo. The present study reports infection of organotypic slice cultures from rat brain with N. fowleri and compares the findings in this culture system with in vivo infection in a rat model of PAM, that proved complementary to that of mice. We found that brain morphology, as present in vivo, is well retained in organotypic slice cultures, and that infection time-course including tissue damage parallels the observations in vivo in the rat. Therefore, organotypic slice cultures from rat brain offer a new in vitro approach to study N. fowleri infection in the context of PAM.

  12. Amifostine, a radioprotectant agent, protects rat brain tissue lipids against ionizing radiation induced damage: An FTIR microspectroscopic imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Cakmak G.; Miller L.; Zorlu, F.; Severcan, F.

    2012-03-03

    Amifostine is the only approved radioprotective agent by FDA for reducing the damaging effects of radiation on healthy tissues. In this study, the protective effect of amifostine against the damaging effects of ionizing radiation on the white matter (WM) and grey matter (GM) regions of the rat brain were investigated at molecular level. Sprague-Dawley rats, which were administered amifostine or not, were whole-body irradiated at a single dose of 800 cGy, decapitated after 24 h and the brain tissues of these rats were analyzed using Fourier transform infrared microspectroscopy (FTIRM). The results revealed that the total lipid content and CH{sub 2} groups of lipids decreased significantly and the carbonyl esters, olefinic=CH and CH{sub 3} groups of lipids increased significantly in the WM and GM after exposure to ionizing radiation, which could be interpreted as a result of lipid peroxidation. These changes were more prominent in the WM of the brain. The administration of amifostine before ionizing radiation inhibited the radiation-induced lipid peroxidation in the brain. In addition, this study indicated that FTIRM provides a novel approach for monitoring ionizing radiation induced-lipid peroxidation and obtaining different molecular ratio images can be used as biomarkers to detect lipid peroxidation in biological systems.

  13. Bioimaging of metals in brain tissue by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and metallomics.

    Science.gov (United States)

    Becker, J Sabine; Matusch, Andreas; Palm, Christoph; Salber, Dagmar; Morton, Kathryn A; Becker, J Susanne

    2010-02-01

    Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been developed and established as an emerging technique in the generation of quantitative images of metal distributions in thin tissue sections of brain samples (such as human, rat and mouse brain), with applications in research related to neurodegenerative disorders. A new analytical protocol is described which includes sample preparation by cryo-cutting of thin tissue sections and matrix-matched laboratory standards, mass spectrometric measurements, data acquisition, and quantitative analysis. Specific examples of the bioimaging of metal distributions in normal rodent brains are provided. Differences to the normal were assessed in a Parkinson's disease and a stroke brain model. Furthermore, changes during normal aging were studied. Powerful analytical techniques are also required for the determination and characterization of metal-containing proteins within a large pool of proteins, e.g., after denaturing or non-denaturing electrophoretic separation of proteins in one-dimensional and two-dimensional gels. LA-ICP-MS can be employed to detect metalloproteins in protein bands or spots separated after gel electrophoresis. MALDI-MS can then be used to identify specific metal-containing proteins in these bands or spots. The combination of these techniques is described in the second section.

  14. 早期应用高压氧对脑梗死患者日常生活活动能力的影响%The effect of early hyperbaric oxygenation on ability of daily life of patients with stroke

    Institute of Scientific and Technical Information of China (English)

    杨晓娟; 李凯; 何韬

    2003-01-01

    BACKGROUND:Brain tissue is often thought as the most vigorous organ and is very sensitive to hypoxia.Hyperbaric oxygenation means improving blood oxygen content for decreasing the brain harm caused by stroke.Anaerobic metabolism of brain tissue decreases and aerobic metabolism increases,which cause more power and accelerate clearing of acidic product of metabolism,so provide fine material base for regeneration of neural tissue and recovery of neural function.

  15. The expression of Fetuin-A in brain tissues of WAG/Rij Rats, genetic rat model of absence epilepsy

    Directory of Open Access Journals (Sweden)

    Ramazan Yüksel

    2015-12-01

    Full Text Available Objective: In the present study, we aimed to determine the Fetuin-A levels in different regions of the brain in absence epileptic Wistar Albino Glaxo/Rijswijk (WAG/Rij rats in order to contribute the identification of new potential biomarkers of the diagnosis, prognosis and follow up the epilepsy treatment. Methods: 1, 3 and 6 months old male WAG/Rij rats (n=21 with absence epilepsy were used in this study. All of the rats were decapitated under anesthesia and their cortex and thalamus tissues were isolated. Fetuin-A levels of the groups were determined by Western Blot method by using standard techniques and differences between densities of the groups were compared. Results: According to data obtained, there was no Fetuin-A expression in brain cortex and thalamus tissues of WAG/Rij rats with absence epilepsy. Conclusion: In this study, it was shown that Fetuin-A is not expressed in brain cortex and thalamus tissues of WAG/Rij rats with absence epilepsy throughout the age-related development. By evaluating the findings obtained, extensive researches that contain molecular and histological methods must be planned, Fetuin-A findings that are obtained experimentally must be confirmed. J Clin Exp Invest 2015; 6 (4: 387-390

  16. Realistic Numerical and Analytical Modeling of Light Scattering in Brain Tissue for Optogenetic Applications(1,2,3).

    Science.gov (United States)

    Yona, Guy; Meitav, Nizan; Kahn, Itamar; Shoham, Shy

    2016-01-01

    In recent years, optogenetics has become a central tool in neuroscience research. Estimating the transmission of visible light through brain tissue is of crucial importance for controlling the activation levels of neurons in different depths, designing optical systems, and avoiding lesions from excessive power density. The Kubelka-Munk model and Monte Carlo simulations have previously been used to model light propagation through rodents' brain tissue, however, these prior attempts suffer from fundamental shortcomings. Here, we introduce and study two modified approaches for modeling the distributions of light emanating from a multimode fiber and scattering through tissue, using both realistic numerical Monte Carlo simulations and an analytical approach based on the beam-spread function approach. We demonstrate a good agreement of the new methods' predictions both with recently published data, and with new measurements in mouse brain cortical slices, where our results yield a new cortical scattering length estimate of ∼47 µm at λ = 473 nm, significantly shorter than ordinarily assumed in optogenetic applications.

  17. Two-dimensional zymography differentiates gelatinase isoforms in stimulated microglial cells and in brain tissues of acute brain injuries.

    Science.gov (United States)

    Chen, Shanyan; Meng, Fanjun; Chen, Zhenzhou; Tomlinson, Brittany N; Wesley, Jennifer M; Sun, Grace Y; Whaley-Connell, Adam T; Sowers, James R; Cui, Jiankun; Gu, Zezong

    2015-01-01

    Excessive activation of gelatinases (MMP-2/-9) is a key cause of detrimental outcomes in neurodegenerative diseases. A single-dimension zymography has been widely used to determine gelatinase expression and activity, but this method is inadequate in resolving complex enzyme isoforms, because gelatinase expression and activity could be modified at transcriptional and posttranslational levels. In this study, we investigated gelatinase isoforms under in vitro and in vivo conditions using two-dimensional (2D) gelatin zymography electrophoresis, a protocol allowing separation of proteins based on isoelectric points (pI) and molecular weights. We observed organomercuric chemical 4-aminophenylmercuric acetate-induced activation of MMP-2 isoforms with variant pI values in the conditioned medium of human fibrosarcoma HT1080 cells. Studies with murine BV-2 microglial cells indicated a series of proform MMP-9 spots separated by variant pI values due to stimulation with lipopolysaccharide (LPS). The MMP-9 pI values were shifted after treatment with alkaline phosphatase, suggesting presence of phosphorylated isoforms due to the proinflammatory stimulation. Similar MMP-9 isoforms with variant pI values in the same molecular weight were also found in mouse brains after ischemic and traumatic brain injuries. In contrast, there was no detectable pI differentiation of MMP-9 in the brains of chronic Zucker obese rats. These results demonstrated effective use of 2D zymography to separate modified MMP isoforms with variant pI values and to detect posttranslational modifications under different pathological conditions.

  18. Brain tissue- and region-specific abnormalities on volumetric MRI scans in 21 patients with Bardet-Biedl syndrome (BBS

    Directory of Open Access Journals (Sweden)

    Johnston Jennifer

    2011-07-01

    Full Text Available Abstract Background Bardet-Biedl syndrome (BBS is a heterogeneous human disorder inherited in an autosomal recessive pattern, and characterized by the primary findings of obesity, polydactyly, hypogonadism, and learning and behavioural problems. BBS mouse models have a neuroanatomical phenotype consisting of third and lateral ventriculomegaly, thinning of the cerebral cortex, and reduction in the size of the corpus striatum and hippocampus. These abnormalities raise the question of whether humans with BBS have a characteristic morphologic brain phenotype. Further, although behavioral, developmental, neurological and motor defects have been noted in patients with BBS, to date, there are limited reports of brain findings in BBS. The present study represents the largest systematic evaluation for the presence of structural brain malformations and/or progressive changes, which may contribute to these functional problems. Methods A case-control study of 21 patients, most aged 13-35 years, except for 2 patients aged 4 and 8 years, who were diagnosed with BBS by clinical criteria and genetic analysis of known BBS genes, and were evaluated by qualitative and volumetric brain MRI scans. Healthy controls were matched 3:1 by age, sex and race. Statistical analysis was performed using SAS language with SAS STAT procedures. Results All 21 patients with BBS were found to have statistically significant region- and tissue-specific patterns of brain abnormalities. There was 1 normal intracranial volume; 2 reduced white matter in all regions of the brain, but most in the occipital region; 3 preserved gray matter volume, with increased cerebral cortex volume in only the occipital lobe; 4 reduced gray m