bluuebunny/crossref_metadata_2025_split huggingface dataset:
Repeatability of a reference region model for analysis of murine DCE‐MRI data at 7T
Authors: Yankeelov Thomas E. , DeBusk Laura M. , Billheimer D. Dean , Luci Jeffrey J. , Lin P. Charles , Price Ronald R. , Gore John C. 
Published: October 2006

AbstractPurposeTo test the repeatability of a reference region (RR) model for the analysis of dynamic contrast‐enhanced MRI (DCE‐MRI) in a mouse model of cancer at high field.Materials and MethodsSeven mice were injected with 106 4T1 mammary carcinoma cells and imaged eight to 10 days later on a Varian 7.0T scanner. Two DCE‐MRI studies were performed for each mouse (separated by 2.5 hours). The RR model was used to analyze the data, and returned estimates on the perfusion‐permeability index (Ktrans) for the RR and the tissue of interest (TOI), as well as the extravascular extracellular volume fraction (ve) for the TOI.ResultsWhen the first injection was compared with the second injection, all parameters tested were highly correlated (r2 = 0.90, 0.62, 0.82 for the RR Ktrans, TOI Ktrans, and TOI ve, respectively, with P < 0.001 for all). To observe a statistically significant change (at the 5% level) in a treatment study with seven animals in each group, log10 changes of 0.084 and 0.077 in the tumor Ktrans and ve, respectively, are required.ConclusionIf a reliable arterial input function (AIF) is unavailable, the RR model is a reasonable alternative to measuring MRI contrast‐agent (CA) kinetics in mouse models of cancer at high field. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Respiratory‐triggered MRCP applying parallel acquisition techniques
Authors: Asbach Patrick , Dewey Marc , Klessen Christian , Stemmer Alto , Ockenga Johann , Huppertz Alexander , Sander Bernhard , Hamm Bernd , Taupitz Matthias 
Published: October 2006

AbstractPurposeTo evaluate the influence of parallel imaging on the image quality of respiratory triggered magnetic resonance cholangiopancreatography (MRCP).Materials and MethodsA total of 30 consecutive patients underwent MRCP applying a respiratory triggered T2‐weighted (T2w) turbo spin‐echo (TSE) sequence without and with parallel imaging (acceleration factor of 2). Acquisition times of both sequences were recorded. Quantitative evaluation included measurement of a contour sharpness index of two segments of the pancreaticobiliary tree as well as calculation of the relative contrast between ductal structures and organ parenchyma at four different segments. The qualitative evaluation was performed by two independent radiologists who graded overall image quality, depiction of eight segments of the pancreaticobiliary tree, and the frequency of artifacts.ResultsThe application of parallel imaging significantly (P < 0.05) reduced the acquisition time of the respiratory triggered MRCP sequence by 37.7% (six minutes and two seconds ± one minute and 26 seconds vs. three minutes and 46 seconds ± 58 seconds). The quantitative and qualitative evaluation revealed no statistically significant differences between the two sequences (P > 0.05). The frequency of artifacts was at the same level for both sequences as well.ConclusionThe application of parallel imaging for respiratory triggered MRCP significantly reduces the acquisition time without relevant influence on image quality. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Chronic oral ascorbic acid therapy worsens skeletal muscle metabolism in patients with chronic heart failure
Authors: Nightingale Angus K. , Crilley Jenifer G. , Pegge Nicholas C. , Boehm Ernie A. , Mumford Catherine , Taylor Doris J. , Styles Peter , Clarke Kieran , Frenneaux Michael P. 
Published: October 2006

AbstractBackground:Chronic heart failure (CHF) is associated with abnormalities of skeletal muscle metabolism. This may be due to impaired oxygen delivery as a result of endothelial dysfunction.Aims:We postulated that ascorbic acid would improve oxygen delivery to exercising muscle and improve skeletal muscle metabolism.Methods:We studied skeletal muscle metabolism using 31P magnetic resonance spectroscopy in 39 CHF patients. Endothelial function was assessed by changes in pulse wave velocity. Subjects were randomised to receive 4g ascorbic acid daily for 4weeks in a placebo‐controlled double‐blind study.Results:Ascorbic acid significantly increased phosphocreatine utilization during exercise. In addition, glycolytic ATP synthesis increased in the ascorbic acid group (change in rate of ATP synthesis at 1min −0.21±0.76 with placebo, 2.06±0.60 following ascorbic acid; p<0.05). Phosphocreatine and ADP recovery after exercise were not changed. The fall in pulse wave velocity during reactive hyperaemia was increased by ascorbic acid from −6.3±2.6% to −12.1±2.0% (p<0.05).Conclusions:These findings suggest that ascorbic acid increased both phosphocreatine utilization and glycolytic ATP synthesis during exercise in patients with CHF implying worsened skeletal muscle metabolism despite improvements in endothelial function.
Mast cells in diffuse large B‐cell lymphoma; their role in fibrosis
Authors: Fukushima H , Ohsawa M , Ikura Y , Naruko T , Sugama Y , Suekane T , Kitabayashi C , Inoue T , Hino M , Ueda M 
Published: October 2006

Aims Mast cells (MCs) are associated with fibrosis in various diseases. MCs comprise two phenotypes: the MCTC phenotype contains tryptase and chymase, whereas the MCT phenotype contains tryptase. Interleukin (IL)‐4 promotes the development of MCTC from the MCT phenotype. The aim of this study was to determine the relationship between MC phenotypes and fibrosis in diffuse large B‐cell lymphoma (DLBCL).Methods and results We examined the distribution and density of MCs in 50 DLBCL and 20 reactive lymph nodes, and evaluated MC phenotypes and IL‐4‐expressing cells. To detect MCs, immunohistochemistry for tryptase and chymase was performed. The 50 DLBCLs were histologically divided into three groups: no fibrosis (32 cases), reticular type (eight cases) showing reticular fibrosis, and bundle type (10 cases) showing collagenous bundles. The density of tryptase‐positive MCs was higher than that of chymase‐positive MCs. The densities of tryptase‐positive and chymase‐positive MCs in fibrotic areas were significantly higher than those in the cellular areas in the reticular and bundle groups. Double immunostaining revealed that MCs in DLBCL comprised MCT and MCTC phenotypes. Chymase‐positive MCs and T lymphocytes expressed IL‐4. Although there were few chymase‐positive MCs in reactive lymph nodes, the density of tryptase‐positive MCs was not different from that in the ‘no fibrosis’ group.Conclusions Tryptase‐positive and chymase‐positive MCs are associated with fibrosis in DLBCL.
Heart failure alters matrix metalloproteinase gene expression and activity in rat skeletal muscle
Authors: Carvalho Robson Francisco , Dariolli Rafael , Justulin Junior Luis Antonio , Sugizaki Mário Mateus , Politi Okoshi Marina , Cicogna Antonio Carlos , Felisbino Sérgio Luis , Dal Pai‐Silva Maeli 
Published: October 2006

SummaryHeart failure is associated with a skeletal muscle myopathy with cellular and extracellular alterations. The hypothesis of this investigation is that extracellular changes may be associated with enhanced mRNA expression and activity of matrix metalloproteinases (MMP). We examined MMP mRNA expression and MMP activity in Soleus (SOL), extensor digitorum longus (EDL), and diaphragm (DIA) muscles of young Wistar rat with monocrotaline‐induced heart failure. Rats injected with saline served as age‐matched controls. MMP2 and MMP9 mRNA contents were determined by RT‐PCR and MMP activity by electrophoresis in gelatin‐containing polyacrylamide gels in the presence of SDS under non‐reducing conditions. Heart failure increased MMP9 mRNA expression and activity in SOL, EDL and DIA and MMP2 mRNA expression in DIA. These results suggest that MMP changes may contribute to the skeletal muscle myopathy during heart failure.
MCP‐1/CCR2 signalling pathway regulates hyperoxia‐induced acute lung injury via nitric oxide production
Authors: Okuma Toshiyuki , Terasaki Yasuhiro , Sakashita Naomi , Kaikita Koichi , Kobayashi Hironori , Hayasaki Takanori , Kuziel William A. , Baba Hideo , Takeya Motohiro 
Published: October 2006

SummaryTo clarify the role of the monocyte chemoattractant protein‐1 (MCP‐1)/C–C chemokine receptor 2 (CCR2) signalling pathway in hyperoxia‐induced acute lung injury, CCR2‐deficient (CCR2−/−) and wild‐type (CCR2+/+) mice were exposed to 85% O2 for up to 6 days. At day 3, body weight significantly decreased and total protein concentration in bronchoalveolar lavage fluid (BALF) was higher in CCR2−/− mice compared with CCR2+/+ mice. Cumulative survivals were significantly lower in CCR2−/− mice than in CCR2+/+ mice. However, the two groups showed no significant differences in both histological changes and number of macrophages in BALF. Real‐time reverse transcriptase‐polymerase chain reaction revealed increased mRNA levels of MCP‐1, interleukin‐1β thioredoxin‐1, and inducible nitric oxide synthase (iNOS) in lung tissues in CCR2−/− mice compared with CCR2+/+ mice. Increased iNOS mRNA levels in alveolar macrophages exposed to 85% O2 for 48 h in vivo or in vitro were significantly higher in CCR2−/− mice than in CCR2+/+ mice. These results suggest that the MCP‐1/CCR2 signalling pathway is protective against hyperoxia‐induced tissue injury by suppressing induction of iNOS and consequent production of reactive oxygen species by activated alveolar macrophages.
Analysis of the expression of HLA class I, proinflammatory cytokines and chemokines in primary tumors from patients with localized and metastatic renal cell carcinoma
Authors: Romero J. M. , Aptsiauri N. , Vazquez F. , Cozar J. M. , Canton J. , Cabrera T. , Tallada M. , Garrido F. , Ruiz‐Cabello F. 
Published: October 2006

AbstractChanges in the human leukocyte antigen (HLA) class I expression and cytokine and chemokine production both by cancer cells and by normal surrounding tissue are believed to be responsible for immune escape and tumor progression. In this study, we compared the tumor expression levels of HLA heavy chain (HLAhc), beta‐2‐microglobulin (β2m), chemokines (Interferon‐gamma‐inducible Protein‐10 (IP‐10), Interferon‐inducible T‐cell Alpha‐Chemoattractant (I‐TAC), Stromal cell‐Derived Factor‐1 (SDF‐1), Macrophage Inflammatory Protein‐1‐alpha (MIP‐1‐α) and Regulated upon Activation, Normally T‐Expressed, and presumably Secreted (RANTES)) and cytokines (Vascular Endothelial Growth Factor (VEGF), Interferon‐gamma (IFN‐γ), Interleukin‐10 (IL‐10), Tumor Growth Factor‐beta (TGB‐β)) in primary tumors and adjacent normal tissues from patients with localized and metastatic renal cell carcinoma (RCC) using a quantitative real‐time polymerase chain reaction technique. We report that the expression of HLAhc, β2m and the studied cytokines and chemokines (except for SDF‐1) was significantly higher in the tumor (29 samples) than in the normal tissue (14 samples). When we compared the tumor expression levels between patients with localized RCC and patients with advanced metastatic stage, we found that the messenger RNA expression levels of HLAhc and β2m were much lower in patients with metastatic RCC (6 cases) than in patients with localized cancer (23 cases), with levels similar to those in normal tissue. This was also confirmed on a protein level by immunohistological labeling of tumor tissues. Thirty‐nine percent of the analyzed RCC tumors showed partial loss of HLA class I molecules, while 6% of the tumors showed HLA class I total loss. The expression of IP‐10, SDF‐1 and VEGF‐c was also significantly lower in patients with advanced tumor, while the IFN‐γ expression in metastatic RCC was not detectable. Our findings show that primary RCC tumors are characterized by a high expression of HLAhc and a presence of proinflammatory mediators and chemokines. We also observed that disease progression and development of metastasis in RCC are associated with decreased expression of HLAhc, β2m, IP‐10, SDF‐1 and IFN‐γ. This microenvironment may suppress the cytotoxic response, creating conditions that favor tumor escape and cancer progression.
HEXOSE TRANSLOCATION ACROSS THE BLOOD‐BRAIN INTERFACE: CONFIGURATIONAL ASPECTS1
Authors: Bidder T. George 
Published: October 2006

Abstract— The translocation of intravenously administered tritiated 3‐O‐methyl‐d‐glucopyranose (3‐OMG) into brain has been studied in an intact nephrectomized rat preparation by infusing a series of hexoses into one internal carotid artery.3‐OMG rapidly penetrated into brain with peak concentrations, attained 5–8 min after injection, declining to relatively constant values thereafter.3‐OMG penetration exhibited saturation characteristics as shown by a levelling‐off in the rate of translocation as its calculated blood concentration was elevated above 50 m‐moles per 1000 ml.Infusion of d‐galactose, d‐glucose, 2‐deoxyglucose, d‐xylose and d‐mannose significantly reduced the translocation of 3‐OMG into brain on the side on which each was infused. d‐glucosamine, d‐mannitol and d‐arabinose were without effect.The phenomenon of countertransport was demonstrated in the nephrectomized rat given tritiated 3‐OMG 20 hr prior to infusion of d‐glucose or d‐mannose into one carotid artery. Each of these hexoses reduced brain 3‐OMG concentration on the side on which it was infused.These results support the hypothesis that the translocation of certain hexoses across the blood‐brain interface is a carrier‐mediated process.
CHANGES IN NUCLEAR RNA OF BRAIN INDUCED BY OLFACTION IN CATFISH
Authors: Rappoport D. A. , Daginawala H. F. 
Published: October 2006

Abstract— —Studies were undertaken to correlate the changes in the synthesis of brain nuclear RNA during olfactory stimulation in saltwater catfish (Galeichthys felis). Catfish allowed to swim for 1 hr in sea water containing morpholine (10−4 M) showed an increase in brain nuclear RNA and a change in base ratios in contrast to controls in plain sea water. These changes in brain nuclear RNA were reversed within 24 hr to the levels of unstimulated controls when morpholine stimulated fish were transferred to fresh sea water.In a split‐brain preparation in an isolated catfish head, one naris was washed with morpholine in sea water (10−6 M), while the other naris was washed with plain sea water. The stimulated half of the brain, compared to the unstimulated half, showed the same changes in nuclear RNA as those noted in free swimming catfish. Brain cytoplasmic fractions did not exhibit any changes in RNA following olfactory stimulation. Amyl acetate, shrimp extract, and extracts from red fish skin as odorants also elicited changes in brain nuclear RNA. With each odorant there was an increase in amount of RNA and also a change in base ratio, where the base ratio changes were different for each odorant tested. With camphor as an odorant, there was an increase in brain nuclear RNA, while with menthol as an odorant, there was a decrease in brain nuclear RNA. In both instances the base ratio of the RNA did not change in contrast to the controls. These studies suggest that olfactory stimulants affect a change in content and character of the RNA in brain nuclei, whereas irritants to the olfactory epithelium change the content of brain nuclear RNA but do not alter the base ratio.
LEVELS OF METABOLITES AND PRODUCTION OF GLUCOSE IN THE LAMPREY BRAIN 1
Authors: Rovainen C. M. , Lowry O. H. , Passonneau J. V. 
Published: October 2006

Abstract—The levels of ATP, phosphocreatine, glucose, glucose‐6‐P., lactate, and glycogen have been measured in brains and spinal cords of lamprey larvae. Levels of glycogen in the brains were high, sometimes exceeding 100 m‐moles of glycosyl units/kg wet weight. Isolated brains incubated in oxygenated saline exhibited the same levels of ATP and phosphocreatine as brains of intact animals. The level of glucose in tissue water of isolated brains approximated that found in the medium, except at low concentrations where the brains maintained levels of glucose many times that of the medium. It is demonstrated that under metabolic stress lamprey brains produce glucose by the breakdown of glycogen and the probable action of a glucose‐6‐phosphatase. The hypothesis is proposed that cells of the brain exchange glucose by this mechanism.
PYRIDOXINE DEFICIENCY IN THE NEONATAL RAT
Authors: Dakshinamurti K. , Stephens M. C. 
Published: October 2006

Abstract—Production of congenital Vitamin B6 (pyridoxine) deficiency in the neonatal rat is reported. Maternal pyridoxine deficiency resulted in pups with retarded neurological development and in some cases, convulsions. Litters were analysed in the neonatal period for the following: pyridoxal 5′‐phosphate and glutamic decarboxylase in whole brain, glutamic‐oxalacetic and glutamic‐pyruric transaminases in plasma and erythrocytes together with concentration of haemoglobin. The biochemical determinations confirm the existence of pyridoxine deficiency at birth.
TETRODOTOXIN ON THE SODIUM AND OTHER IONS OF CEREBRAL TISSUES, EXCITED ELECTRICALLY AND WITH GLUTAMATE
Authors: McIlwain H. , Harvey J. A. , Rodriguez G. 
Published: October 2006

Abstract—Guinea pig neocortical tissues incubated in glucose‐bicarbonate salines maintained defined intracellular Na concentrations which were about 0.25 those of the salines and were unaffected by tetrodotoxin.Electrical stimulation or the addition of 5 mm‐l‐glutamic acid allowed tissue Na to increase at about 400,μequiv./g hr. Tetrodotoxin almost completely prevented the increase induced electrically, and partly inhibited that induced by glutamate. Influx of22Na induced by glutamate was also partly inhibited by the toxin. The extrusion of Na following electrical excitation was unaffected by tetrodotoxin.The concentration of tetrodotoxin needed for half‐maximal inhibition of Na movement induced electrically, was 25–30 mμm. Action of the toxin was reversed by washing the tissue, and the tetrodotoxin associated with the tissue during its action was probably no more than 0 15 mμmoles/g tissue.Structurala factors common to the molecules of tetrodotoxin, glutamic acid and membrane components considered to be involved in cation movements, are indicated.
CHANGES IN METABOLITES OF THE ENERGY RESERVES IN INDIVIDUAL LAYERS OF MOUSE CEREBRAL CORTEX AND SUBJACENT WHITE MATTER DURING ISCHAEMIA AND ANAESTHESIA1
Authors: Folbergrová Jaroslava , Lowry O. H. , Passonneau Janet V. 
Published: October 2006

Abstract—The distribution of glucose, glycogen, ATP, P‐creatine and inorganic phosphate was measured in layers I, III, IV, V and VI of cerebral cortex and subjacent white matter of mouse brain. ATP, P‐creatine and inorganic phosphate were evenly distributed in all regions examined, whereas levels of glucose and glycogen were higher in white matter than the average for the other layers. Anaesthesia increased levels of glucose and P‐creatine in layers I and V and subjacent white matter (other layers were not examined). Anaesthesia doubled the level of glycogen in molecular layer I with lesser increases in layers III, IV, V and VI, but with no change in white matter from the unanaesthetized control value.The metabolic rates in the individual layers were estimated from the rates of expenditure of energy reserves during total ischaemia. In non‐anaesthetized mice, white matter had a higher metabolic rate than either layer I or V. Anaesthesia reduced the metabolic rates in all layers; however, the largest reduction occurred in subjacent white matter (86 per cent), with reductions of 54 per cent and 76 per cent respectively in layers I and V.
CHANGES IN FREE FATTY ACIDS OF BRAIN BY DRUG‐INDUCED CONVULSIONS, ELECTROSHOCK AND ANAESTHESIA
Authors: Bazán N. G. 
Published: October 2006

Abstract— The size of the free fatty acid pool in rat brain was significantly increased following convulsions induced by pentylenetetrazol as well as by electroconvulsive shock. Other convulsants such as d‐methionine‐dl‐sulphoximine and the dibutyryl analog of adenosine 3′,5′‐monophosphate did not alter the levels of free fatty acids.Diethyl ether anaesthesia suppressed the stimulatory effect of electroshock on the generation of free fatty acids in brain, but the effect was not seen with the anaesthetic pentobarbitone sodium. The lack of an inhibitory effect of either anaesthetic on the free fatty acid production which was induced in brain by ischaemia supported the view that the action of electroshock was not merely the result of anoxia.The prominent increase in size of the free fatty acid pool in brain thus appeared to be specific for electroshock‐ and pentylenetetrazol‐convulsed rats.We have proposed that the changes in the free fatty acids might be involved in the regulation of membrane functioning.
AMINO ACID DISTRIBUTION AND INCORPORATION INTO PROTEINS IN ISOLATED, ELECTRICALLY‐STIMULATED CEREBRAL TISSUES
Authors: Jones D. A. , McIlwain H. 
Published: October 2006

Abstract—The uptake of radioactive amino acid by incubated cerebral cortex slices is found to be a first order process. Incorporation of the radioactive amino acid into tissue protein is from a precursor pool that has first equilibrated with the intracellular endogenous free amino acids. Ways of calculating the amino acid incorporation in molar quantities from the observed incorporation of radioactivity are discussed, and it is concluded that the specific radioactivity of the intracellular acid‐soluble fraction is the best basis for such estimates. The in vitro incorporation of leucine into tissue protein is estimated to be approximately 1±2 mμnol/mg protein/h, and of valine 0±4 mμmol/mg protein/h.Addition of free amino acids to the media had little or no effect on the calculated rates of incorporation. On incubation for 1 h the total free valine in tissue and medium increased by 0±43 μmol/g and leucine increased by 0±55 μmol/g. Estimates of amino acid incorporation based on the specific radioactivity of the media amino acids can give misleading results if this considerable release of amino acids into the medium is not taken into account. Electrical stimulation of neocortical slices with a variety of types of pulses was either without effect or decreased incorporation into portein. The decrease could not be directly correlated with changes in tissue K+ nor with the utilization of ATP. Mild, local stimulation of the lateral olfactory tract of piriform cortex slices was without effect on tissue phosphocreatine, K+ or amino acid incorporation.
MONOAMINE OXIDASE: AN APPROXIMATION OF TURNOVER RATES
Authors: Goridis C. , Neff N. H. 
Published: October 2006

AbstractOne hour after the intravenous injection of pargyline (10 mg/kg), the activity of monoamine oxidase (EC 1.4.3.4) in various brain regions, in the submaxillary gland and in the superior cervical ganglion of the rat was inhibited by about 95 per cent. From the return of monoamine oxidase activity with time, we estimated that the half‐life of the enzyme is about 11 days in the brain and 4 days in the submaxillary gland and superior cervical ganglion. The return of activity was inhibited by treatment with cycloheximide. The half‐life of monoamine oxidase in brain regions bore no relationship to the turnover rates of the monoamines.