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1.
AJNR Am J Neuroradiol ; 45(2): 139-148, 2024 02 07.
Article in English | MEDLINE | ID: mdl-38164572

ABSTRACT

Resting-state (rs) fMRI has been shown to be useful for preoperative mapping of functional areas in patients with brain tumors and epilepsy. However, its lack of standardization limits its widespread use and hinders multicenter collaboration. The American Society of Functional Neuroradiology, American Society of Pediatric Neuroradiology, and the American Society of Neuroradiology Functional and Diffusion MR Imaging Study Group recommend specific rs-fMRI acquisition approaches and preprocessing steps that will further support rs-fMRI for future clinical use. A task force with expertise in fMRI from multiple institutions provided recommendations on the rs-fMRI steps needed for mapping of language, motor, and visual areas in adult and pediatric patients with brain tumor and epilepsy. These were based on an extensive literature review and expert consensus.Following rs-fMRI acquisition parameters are recommended: minimum 6-minute acquisition time; scan with eyes open with fixation; obtain rs-fMRI before both task-based fMRI and contrast administration; temporal resolution of ≤2 seconds; scanner field strength of 3T or higher. The following rs-fMRI preprocessing steps and parameters are recommended: motion correction (seed-based correlation analysis [SBC], independent component analysis [ICA]); despiking (SBC); volume censoring (SBC, ICA); nuisance regression of CSF and white matter signals (SBC); head motion regression (SBC, ICA); bandpass filtering (SBC, ICA); and spatial smoothing with a kernel size that is twice the effective voxel size (SBC, ICA).The consensus recommendations put forth for rs-fMRI acquisition and preprocessing steps will aid in standardization of practice and guide rs-fMRI program development across institutions. Standardized rs-fMRI protocols and processing pipelines are essential for multicenter trials and to implement rs-fMRI as part of standard clinical practice.


Subject(s)
Brain Neoplasms , Epilepsy , Humans , Child , Adult , Brain Mapping/methods , Magnetic Resonance Imaging/methods , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/surgery , Epilepsy/diagnostic imaging , Epilepsy/surgery , Language , Brain/diagnostic imaging
2.
Diabetes Obes Metab ; 10(9): 772-9, 2008 Sep.
Article in English | MEDLINE | ID: mdl-17970759

ABSTRACT

AIM: We investigated the effects of the combined therapy of PPARgamma and PPARalpha agonists on HDL metabolism, especially concerning reverse cholesterol transport (RCT), using Zucker diabetic fatty rats (ZDF/Crl-Lepr fa rats) that are the rodent model for type 2 diabetes with obesity, hyperlipidaemia and insulin resistance. METHODS: The ZDF rats were divided into four medicated groups as follows: pioglitazone as a PPARgamma agonist (5 mg/kg/day; P group, n = 6), fenofibrate as a PPARalpha agonist (30 mg/kg/day; F group, n = 6), both these medications (P + F group, n = 6) and no treatment (UNT group, n = 6). Non-diabetic rats (ZDF/GmiCrl-lean, CON group, n = 6) served as controls. We evaluated HDL particle size and messenger RNA (mRNA) levels of the following factors: liver X receptor alpha (L x R alpha), ATP-binding cassette A1 (ABCA1) and ABCG1 which are regulated by PPARs and are related to early stage RCT. RESULTS: The significant increase in HDL particle size was demonstrated in rats of the F and P + F groups, although changes in plasma HDL-cholesterol levels were not significant. In accordance with this finding, mRNA levels of ABCG1 in the liver increased significantly. CONCLUSIONS: These findings suggest the efficacy of combined therapy with PPARgamma and PPARalpha in improving lipid metabolism, partly through the enhanced RCT, and insulin resistance in type 2 diabetes mellitus.


Subject(s)
Cholesterol, HDL/metabolism , Diabetes Mellitus, Type 2/drug therapy , Fenofibrate/administration & dosage , Hyperlipidemias/drug therapy , Hypoglycemic Agents/administration & dosage , Thiazolidinediones/administration & dosage , ATP Binding Cassette Transporter 1 , ATP-Binding Cassette Transporters/analysis , Animals , Blood Glucose/drug effects , Blood Glucose/metabolism , DNA-Binding Proteins/analysis , Diabetes Mellitus, Experimental , Diabetes Mellitus, Type 2/metabolism , Hyperlipidemias/metabolism , Hypoglycemic Agents/agonists , Insulin Resistance , Lipid Metabolism , Liver X Receptors , Male , Obesity/metabolism , Orphan Nuclear Receptors , PPAR alpha/agonists , PPAR gamma/agonists , Pioglitazone , Rats , Rats, Zucker , Receptors, Cytoplasmic and Nuclear/analysis
3.
Oncogene ; 8(2): 379-86, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8426744

ABSTRACT

In the early event of the induction of mouse erythroleukemia (MEL) cell differentiation, c-myc mRNA levels show a drastic change. The elevated expression of a transfected c-myc gene inhibits the commitment and differentiation of MEL cell transformants. In the present work, we have introduced human c-myc mutants into MEL cells under the inducible promoter to define the functional domains of c-Myc involved in erythroid differentiation. The c-Myc domains necessary for commitment and differentiation are not co-localized; almost entire regions are required for inhibition of commitment, whereas domains II and IV that are essential for co-transforming activity with ras are required for inhibition of differentiation. Interestingly, mutants that delete domains for c-Myc dimerization motifs enhanced differentiation. These results suggest that c-Myc may regulate commitment and differentiation by interacting with proteins through different domains.


Subject(s)
Genes, myc , Leukemia, Erythroblastic, Acute/pathology , Animals , Cell Differentiation , Humans , Mice , Mutation , Retinoblastoma Protein/metabolism , Transfection , Zinc/pharmacology
4.
Biochim Biophys Acta ; 1361(2): 138-46, 1997 Aug 22.
Article in English | MEDLINE | ID: mdl-9300795

ABSTRACT

Recombinant rat macrophage inflammatory protein 2 (MIP-2) was prepared from E. coli transfected with a glutathione-S-transferase (GST)-MIP-2 fusion protein expression vector. A polyclonal antibody to rat MIP-2 was then obtained from rabbits by immunization with recombinant rat MIP-2. Using the polyclonal antibody which selectively suppressed neutrophil chemotactic activity of MIP-2, the role of MIP-2 in neutrophil infiltration in allergic inflammation in rats was studied. In an air pouch-type allergic inflammation model in rats, neutrophil infiltration into the pouch fluid increased with time after antigen challenge. Neutrophil chemotactic activity in the pouch fluid collected 8 h after antigen challenge was diminished by anti-MIP-2 antibody. In addition, when leukocytes that had infiltrated into the pouch fluid collected 4 h after antigen challenge were incubated, neutrophil chemotactic activity in the conditioned medium increased time-dependently, and the activity was neutralized by anti-MIP-2 antibody. Furthermore, when anti-MIP-2 antibody was injected into the pouch 6 h after antigen challenge, neutrophil infiltration into the pouch fluid during the next 2 h was suppressed. These findings indicate that MIP-2 plays an important role in neutrophil infiltration in rat allergic inflammation.


Subject(s)
Chemotactic Factors/immunology , Hypersensitivity, Immediate/physiopathology , Inflammation/physiopathology , Monokines/immunology , Neutrophils/physiology , Amino Acid Sequence , Animals , Antibodies/administration & dosage , Antibodies/immunology , Antigen-Antibody Reactions , Body Fluids/immunology , Cheek , Chemokine CXCL2 , Chemotactic Factors/administration & dosage , Cloning, Molecular , Hypersensitivity, Immediate/immunology , Inflammation/immunology , Molecular Sequence Data , Monokines/administration & dosage , Rats , Recombinant Proteins/immunology
5.
J Cereb Blood Flow Metab ; 12(3): 359-70, 1992 May.
Article in English | MEDLINE | ID: mdl-1569133

ABSTRACT

Two strategies were used to estimate the blood flow threshold for focal cerebral infarction in spontaneously hypertensive rats (SHRs) subjected to permanent middle cerebral artery and common carotid artery occlusion (MCA/CCAO). The first compared the volume of cortical infarction (24 h after ischemia onset) to the volumes of ischemic cortex (image analysis of [14C]iodoantipyrine CBF autoradiographs) perfused below CBF values less than 50 (VIC50) and less than 25 ml 100 g-1 min-1 (VIC25) at serial intervals during the first 3 h of ischemia. The infarct process becomes irreversible within 3 h in this model. In the second, measurements of CBF at the border separating normal from infarcted cortex at 24 h after ischemia onset were used as an index of the threshold. During the first 3 h of ischemia, VIC50 increased slightly to reach a maximum size at 3 h that closely matched the 24 h infarct volume. VIC25, in contrast, consistently underestimated the infarct volume by a factor of 2-3. CBF at the 24 h infarct border averaged 50 ml 100 g-1 min -1. Taken together, the results indicate that the CBF threshold for infarction in SHRs approaches 50 ml 100 g-1 min-1 when ischemia persists for greater than or equal to 3 h. This threshold value is approximately three times higher than in primates. Since cortical neuronal density is also threefold greater in rats than in primates, the higher injury threshold in the rat may reflect a neuronal primacy in determining the brain's susceptibility to partial ischemia.


Subject(s)
Brain Ischemia/physiopathology , Cerebral Infarction/physiopathology , Cerebrovascular Circulation , Animals , Autoradiography , Blood Flow Velocity , Disease Models, Animal , Edema/physiopathology , Male , Rats , Rats, Inbred SHR , Regional Blood Flow , Time Factors
6.
J Cereb Blood Flow Metab ; 10(1): 89-96, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2298839

ABSTRACT

Focal cerebral infarction and edema were measured in rats (Wistar, Fisher 344, and spontaneously hypertensive strains) pretreated with nimodipine (2 micrograms/kg/min i.v.) or its vehicle and subjected to the tandem occlusion of the middle cerebral and common carotid arteries. Animals awoke from anesthesia 10-15 min after onset of ischemia and continued to receive treatment over a 24-h survival period. Cortical infarction and edema were quantified by image analysis of frozen brain sections processed for histology. Nimodipine-treated rats developed 20-60% smaller cortical infarct volumes than controls (p less than 0.002). Cortical edema was reduced proportionately to the decrease in infarct volume and constituted approximately 36% of the infarct volume. Nimodipine caused a mild hypotensive response that did not aggravate ischemic brain damage. The results indicate that continuous nimodipine treatment, started before induction of focal cerebral ischemia, can attenuate ischemic brain damage and edema as late as 24 h after the onset of ischemia.


Subject(s)
Brain Ischemia/complications , Cerebral Infarction/physiopathology , Nimodipine/pharmacology , Animals , Blood Pressure/physiology , Blood Volume , Brain Edema/etiology , Brain Edema/physiopathology , Cerebral Infarction/etiology , Male , Rats
7.
J Cereb Blood Flow Metab ; 8(4): 474-85, 1988 Aug.
Article in English | MEDLINE | ID: mdl-3392112

ABSTRACT

This article describes a 3-year experience with focal neocortical ischemia in three rat strains. Multiple groups of adult Wistar (n = 50), Fisher 344 (n = 31), and spontaneously hypertensive (n = 72) rats were subjected to permanent occlusion of the distal middle cerebral (MCA) and ipsilateral common carotid arteries (CCA). Twenty-four hours later the animals were killed, and frozen brain sections were stained with hematoxylin and eosin to demarcate infarcted tissue. The infarct volume for each section was quantified with an image analyzer, and the total infarct volume was calculated with an iterative program that summed all interval volumes. Neocortical infarct volume was the largest and most reproducible in the spontaneously hypertensive rats (SHR). Statistical power analysis to project the numbers of animals necessary to detect a 25 or 50% change in infarct volume with alpha = 0.05 and beta = 0.2 revealed that only the SHR model was practical in terms of requisite animals: i.e., less than 10 animals per group. Tandem occlusion of the distal MCA and ipsilateral CCA in the SHR strain provides a surgically simple method for causing large neocortical infarcts with reproducible topography and volume. The interanimal variability in infarct volume that occurs even in the SHR strain dictates that randomized, concomitant controls are necessary in each study to ensure the accurate assessment of experimental manipulations or pharmacologic therapies.


Subject(s)
Brain Ischemia/complications , Carotid Arteries , Cerebral Arteries , Cerebral Infarction/etiology , Animals , Arterial Occlusive Diseases/physiopathology , Behavior, Animal , Cerebral Cortex , Cerebral Infarction/pathology , Cerebral Infarction/physiopathology , Cerebrovascular Circulation , Disease Models, Animal , Male , Rats , Rats, Inbred F344 , Rats, Inbred SHR , Rats, Inbred Strains
8.
J Cereb Blood Flow Metab ; 10(6): 903-13, 1990 Nov.
Article in English | MEDLINE | ID: mdl-2211883

ABSTRACT

The effect of nimodipine pretreatment on CBF and brain edema was studied in conscious rats subjected to 2.5 h of focal cortical ischemia. An infusion of nimodipine (2 micrograms/kg/min i.v.) or its vehicle, polyethylene glycol 400, was begun 2 h before the ischemic interval and was continued throughout the survival period. Under brief halothane anesthesia, the animals' right middle cerebral and common carotid arteries were permanently occluded, and 2.5 h later, they underwent a quantitative CBF study ([14C]iodoantipyrine autoradiography followed by Quantimet 970 image analysis). Nimodipine treatment improved blood flow to the middle cerebral artery territory without evidence of a "vascular steal" and reduced the volume of the ischemic core (cortex with CBF of less than 25 ml/100 g/min) and accompanying edema by approximately 50% when compared with controls (p = 0.006 and 0.0004, respectively). Mild hypotension induced by nimodipine did not aggravate the ischemic insult. The ischemic core volumes, however, were 50-75% smaller than the 24-h infarct volumes generated in a similar paradigm that demonstrated 20-30% infarct reduction with continuous nimodipine treatment. These results suggest that nimodipine pretreatment attenuates the severity of early focal cerebral ischemia, but that with persistent ischemia, cortex surrounding the ischemic core undergoes progressive infarction and the early benefit of nimodipine treatment is only partly preserved.


Subject(s)
Brain Edema/drug therapy , Brain Ischemia/drug therapy , Cerebrovascular Circulation/drug effects , Nimodipine/therapeutic use , Animals , Male , Nimodipine/pharmacology , Premedication , Rats , Rats, Inbred Strains
9.
Arch Neurol ; 56(7): 809-14, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10404982

ABSTRACT

BACKGROUND: The mechanism of dementia in subcortical cerebral infarction is incompletely understood. OBJECTIVE: To determine how cognitive function is related to cortical metabolism in patients with subcortical infarction and a continuum of cognitive impairment. METHODS: We used positron emission tomography (PET) and the glucose metabolic tracer fludeoxyglucose F 18 to study 8 patients with subcortical stroke and normal cognitive function (S-CN), 5 patients with subcortical stroke and cognitive impairment (S-CI) who did not have dementia, 8 patients with subcortical stroke and dementia (S-D), and 11 controls with no cognitive impairment or stroke. A subset of patients had absolute regional cerebral metabolic rate of glucose (CMRglc) determined, while in all subjects regional tracer uptake normalized to whole brain tracer uptake was calculated. PET data were analyzed by constructing volumes of interest using coregistered magnetic resonance imaging data and correcting the PET data for atrophy. RESULTS: Global CMRglc was significantly lower in the patients with S-D than in the control and S-CN groups, with S-CI rates intermediate to those of the S-D and S-CN groups. Absolute regional CMRs of glucose were similar in the S-D and S-CI groups and in the control and S-CN groups. The regional pattern, however, showed lower right frontal regional CMRglc ratios in all stroke groups compared with the controls. There were modest correlations between performance on the Mini-Mental State Examination and whole brain CMRglc when all 4 groups were included. CONCLUSIONS: These results demonstrate that subcortical infarction produces global cerebral hypometabolism, which is related to the clinical status of the patients. In addition, specific frontal lobe hypometabolism also appears to be a feature of subcortical infarction. Taken together, both global and regional effects on cortical function mediate the production of clinical symptoms in patients with subcortical strokes.


Subject(s)
Cerebral Infarction/complications , Cognition Disorders/etiology , Cognition Disorders/metabolism , Frontal Lobe/metabolism , Frontal Lobe/pathology , Glucose/metabolism , Aged , Atrophy/pathology , Brain/pathology , Cognition Disorders/diagnosis , Female , Frontal Lobe/diagnostic imaging , Humans , Magnetic Resonance Imaging , Male , Neuropsychological Tests , Severity of Illness Index , Tomography, Emission-Computed , Tomography, Emission-Computed, Single-Photon
10.
Neurology ; 55(11): 1626-35, 2000 Dec 12.
Article in English | MEDLINE | ID: mdl-11113215

ABSTRACT

BACKGROUND: The cause of dementia in subcortical ischemic vascular disease (SIVD) is controversial. OBJECTIVES: To determine whether cognitive impairment in SIVD 1) correlates with measures of ischemic brain injury or brain atrophy, and/or 2) is due to concomitant AD. METHODS: Volumetric MRI of the brain was performed in 1) elderly subjects with lacunes (L) and a spectrum of cognitive impairment-normal cognition (NC+L, n = 32), mild cognitive impairment (CI+L, n = 26), and dementia (D+L, n = 29); 2) a comparison group with probable AD (n = 28); and 3) a control group with normal cognition and no lacunes (NC). The authors examined the relationship between the severity of cognitive impairment and 1) volume, number, and location of lacunes; 2) volume of white matter signal hyperintensities (WMSH); and 3) measures of brain atrophy (i. e., hippocampal, cortical gray matter, and CSF volumes). RESULTS: Among the three lacune groups, severity of cognitive impairment correlated with atrophy of the hippocampus and cortical gray matter, but not with any lacune measure. Although hippocampal atrophy was the best predictor of severity of cognitive impairment, there was evidence for a second, partially independent, atrophic process associated with ventricular dilation, cortical gray matter atrophy, and increase in WMSH. Eight autopsied SIVD cases showed variable severity of ischemic and neurofibrillary degeneration in the hippocampus, but no significant AD pathology in neocortex. The probable AD group gave evidence of only one atrophic process, reflected in the severity of hippocampal atrophy. Comparison of regional neocortical gray matter volumes showed sparing of the primary motor and visual cortices in the probable AD group, but relatively uniform atrophy in the D+L group. CONCLUSIONS: Dementia in SIVD, as in AD, correlates best with hippocampal and cortical atrophy, rather than any measure of lacunes. In SIVD, unlike AD, there is evidence for partial independence between these two atrophic processes. Hippocampal atrophy may result from a mixture of ischemic and degenerative pathologies. The cause of diffuse cortical atrophy is not known, but may be partially indexed by the severity of WMSH.


Subject(s)
Brain Ischemia/pathology , Cerebral Cortex/pathology , Dementia, Vascular/pathology , Hippocampus/pathology , Stroke/pathology , Aged , Atrophy/pathology , Brain/pathology , Female , Humans , Magnetic Resonance Imaging , Male
11.
Neurology ; 49(6): 1513-21, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9409338

ABSTRACT

Hippocampal atrophy detected by MRI is a prominent feature of early Alzheimer's disease (AD), but it is likely that MRI underestimates the degree of hippocampal neuron loss, because reactive gliosis attenuates atrophy. We tested the hypothesis that hippocampal N-acetyl aspartate (NAA: a neuronal marker) and volume used together provide greater discrimination between AD and normal elderly than does either measure alone. We used proton MR spectroscopic imaging (1H MRSI) and tissue segmented and volumetric MR images to measure atrophy-corrected hippocampal NAA and volumes in 12 AD patients (mild to moderate severity) and 17 control subjects of comparable age. In AD, atrophy-corrected NAA from the hippocampal region was reduced by 15.5% on the right and 16.2% on the left (both p < 0.003), and hippocampal volumes were smaller by 20.1% (p < 0.003) on the right and 21.8% (p < 0.001) on the left when compared with control subjects. The NAA reductions and volume losses made independent contributions to the discrimination of AD patients from control subjects. When used separately, neither hippocampal NAA nor volume achieved to classify correctly AD patients better than 80%. When used together, however, the two measures correctly classified 90% of AD patients and 94% of control subjects. In conclusion, hippocampal NAA measured by 1H MRSI combined with quantitative measurements of hippocampal atrophy by MRI may improve diagnosis of AD.


Subject(s)
Alzheimer Disease/diagnosis , Alzheimer Disease/metabolism , Aspartic Acid/analogs & derivatives , Hippocampus/metabolism , Hippocampus/pathology , Aged , Aged, 80 and over , Aspartic Acid/metabolism , Atrophy , Female , Humans , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Male , Middle Aged , Protons
12.
Pediatrics ; 63(5): 778-81, 1979 May.
Article in English | MEDLINE | ID: mdl-440900

ABSTRACT

An 11-year-old boy had clinical signs of an acute inferior wall myocardial infarction. On echocardiography, a left atrial myxoma was demonstrated. Coronary artery embolization from myxoma was confirmed by selective coronary arteriography. The tumor was removed 12 days after acute coronary embolization. The clinical value of echocardiography is demonstrated in this report of a successful surgical excision of left atrial myxoma in a child with a myocardial infarction due to tumor embolization.


Subject(s)
Coronary Disease/etiology , Heart Neoplasms/complications , Myxoma/complications , Child , Coronary Angiography , Coronary Disease/complications , Coronary Disease/diagnostic imaging , Echocardiography , Heart Atria , Heart Neoplasms/diagnosis , Humans , Male , Myocardial Infarction/etiology , Myxoma/diagnosis
13.
Br J Pharmacol ; 113(4): 1480-6, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7889305

ABSTRACT

1. In an air pouch-type allergic inflammation model in rats, leucocytes that had infiltrated into the pouch fluid collected 4 h after the antigen challenge produced proteinaceous chemotactic factors for neutrophils when they were incubated in the medium. 2. To clarify the mechanism of activation of the infiltrated leucocytes in producing these factors, the effects of protein kinase inhibitors on neutrophil chemotactic factor production were examined. 3. When the infiltrated leucocytes were incubated for 4 h in medium containing the non-selective protein kinase inhibitor K-252a (1-100 ng ml-1, 2.14-214 nM), the tyrosine kinase inhibitor genistein (1-50 micrograms ml-1, 3.7-185 microM), and the more selective protein kinase C inhibitor H-7 (5-100 micrograms ml-1, 13.7-274 microM); neutrophil chemotactic activity in the conditioned medium was decreased in a concentration-dependent manner, but the adenosine 3':5'-cyclic monophosphate (cAMP)-dependent protein kinase inhibitor H-89 (1-1000 ng ml-1, 2.24-2240 nM) showed no effect. 4. Isoelectric focusing of the conditioned medium revealed that the leucocytes produced two neutrophil chemotactic factors, leucocyte-derived neutrophil chemotactic factor (LDNCF) 1 and LDNCF-2. Treatment of the leucocytes with K-252a, genistein, and H-7, but not H-89, inhibited production of both LDNCF-1 and LDNCF-2. 5. These results suggest that activation of tyrosine kinase and protein kinase C, but not cAMP-dependent protein kinase, is responsible for the production of LDNCF-1 and LDNCF-2. 6. The steroidal anti-inflammatory drug dexamethasone and the protein synthesis inhibitor cycloheximide inhibited neutrophil chemotactic factor production in a concentration-dependent manner. Time-course experiments showed that the inhibitory effect by dexamethasone was apparent even 30 min after the incubation.7. Mechanism for inhibiting the production of LDNCF-1 and LDNCF-2 by dexamethasone is also discussed.


Subject(s)
Chemotactic Factors/biosynthesis , Dexamethasone/pharmacology , Hypersensitivity/metabolism , Inflammation/metabolism , Leukocytes/metabolism , Protein Kinases/metabolism , Sulfonamides , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine , Animals , Carbazoles/pharmacology , Cells, Cultured , Culture Media, Conditioned , Cycloheximide/pharmacology , Depression, Chemical , Genistein , Indole Alkaloids , Isoelectric Focusing , Isoflavones/pharmacology , Isoquinolines/pharmacology , Leukocytes/drug effects , Male , Piperazines/pharmacology , Protein Kinase C/antagonists & inhibitors , Protein Kinase Inhibitors , Protein-Tyrosine Kinases/antagonists & inhibitors , Rats , Rats, Sprague-Dawley
14.
Br J Pharmacol ; 121(8): 1651-8, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9283699

ABSTRACT

1. Incubation of rat peritoneal neutrophils in medium containing various concentrations of staurosporine (6.4-64 nM) increased the neutrophil chemotactic activity in the conditioned medium in a time- and concentration-dependent manner. 2. Separation of the neutrophil chemotactic activity in the conditioned medium by isoelectric focusing revealed that staurosporine (64 nM) stimulated the production of basic (pH > 8) neutrophil chemotactic factors, while TPA (12-O-tetradecanoylphorbol 13-acetate, 49 nM) stimulated the production of both basic (pH > 8) and acidic (pH 5) neutrophil chemotactic factors. 3. Determination by immunoassay of cytokine-induced neutrophil chemoattractant (CINC)-1, -2 alpha, -2 beta and -3 in the conditioned medium at 4 h revealed that staurosporine (64 nM) and TPA (49 nM) strongly stimulated the production of CINC-3 (staurosporine, 133.0 +/- 3.8; TPA, 26.7 +/- 1.0; control, 0.32 +/- 0.01 ng ml-1, means +/- s.e.mean from four samples) compared to CINC-1 (staurosporine, 55.0 +/- 1.2; TPA, 12.2 +/- 0.3; control, 0.56 +/- 0.01 ng ml-1), and CINC-2 alpha (staurosporine, 1.09 +/- 0.03; TPA, 0.90 +/- 0.02; control, < 0.10 ng ml-1). CINC-2 beta was below the detectable amount (< 0.078 ng ml-1). 4. The level of CINC-3 mRNA in the peritoneal neutrophils was determined by reverse transcription-polymerase chain reaction. Staurosporine (64 nM) and TPA (49 nM) enhanced the level of CINC-3 mRNA time-dependently, but had no effect on GAPDH mRNA levels. 5. Production of staurosporine-induced neutrophil chemotactic factor was inhibited by the protein kinase C inhibitors, H-7 (IC50, 12.3 microM), calphostin C (IC50, 0.77 microM) and Ro 31-8425 (24.3% inhibition at 10 microM), and by the tyrosine kinase inhibitor, genistein (IC50, 68.5 microM). Production of TPA-induced neutrophil chemotactic factor was also inhibited by both inhibitors. 6. Both the staurosporine- and the TPA-induced increase in CINC-3 mRNA levels were suppressed by H-7 and genistein.


Subject(s)
Chemokines, CXC , Chemotactic Factors/biosynthesis , Growth Substances/biosynthesis , Intercellular Signaling Peptides and Proteins , Neutrophils/drug effects , Staurosporine/pharmacology , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine/pharmacology , Animals , Chemokine CXCL1 , Chemotactic Factors/genetics , Dose-Response Relationship, Drug , Growth Substances/genetics , Male , Neutrophils/metabolism , Protein Kinase C/physiology , RNA, Messenger/analysis , Rats , Rats, Sprague-Dawley , Tetradecanoylphorbol Acetate/pharmacology
15.
Br J Pharmacol ; 111(1): 123-30, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8012688

ABSTRACT

1. The role of platelet activating factor (PAF) in neutrophil infiltration in air pouch type allergic inflammation in rats was investigated. 2. Neutrophil infiltration into the pouch fluid 8 h after injection of the antigen (azobenzenearsonate-conjugated acetyl bovine serum albumin) solution into the air pouch of immunized rats was inhibited dose-dependently by treatment with PAF antagonists (CV-3988, L-652,731 and Y-24,180) in parallel with the decrease in neutrophil chemotactic activity in the pouch fluid. 3. Four hours after injection of the antigen solution into the air pouch of immunized and non-immunized rats, there was no significant difference between the two groups in the number of total leucocytes, neutrophils, mononuclear cells and eosinophils in the pouch fluid. However, when the infiltrated leucocytes were incubated in medium, chemotactic factor production by leucocytes from immunized rats was greater than that from non-immunized rats. 4. When leucocytes from non-immunized rats were preincubated for various periods in the medium containing 10 or 50 nM of PAF, washed, and further incubated in the medium containing no PAF, chemotactic factor production was not stimulated. 5. The increase in the chemotactic activity in the conditioned medium was not suppressed by the 5-lipoxygenase inhibitor, AA861. In addition, the chemotactic activity in the conditioned medium was not inhibited by the PAF antagonists. 6. Incubation of the infiltrated leucocytes in the medium containing the protein synthesis inhibitor, cycloheximide, inhibited chemotactic factor production in a concentration-dependent manner in parallel with the decrease in uptake of [3H]-leucine into the acid-insoluble fraction of leucocytes. 7. Separation of the chemotactic activity in the conditioned medium by isoelectric focusing revealed that the leucocyte infiltrated into the pouch fluid produce two kinds of factors, viz. leucocyte-derived neutrophil chemotactic factor-i (LDNCF-1) and LDNCF-2 of which pI values are 4-5 and above 8,respectively.8. The results indicate that PAF has no significant role in leucocyte activation to produce chemotactic factors, and that neutrophil chemotactic factors produced by infiltrated leucocytes are not PAF or leukotriene B4 but are produced through a protein synthesis mechanism.9. The mechanism of action of PAF antagonists on neutrophil infiltration into the inflammatory locus is discussed.


Subject(s)
Hypersensitivity/immunology , Interleukin-8/biosynthesis , Leukocytes/metabolism , Platelet Activating Factor/physiology , Animals , Azepines/pharmacology , Benzoquinones/pharmacology , Cells, Cultured , Culture Media, Conditioned , Dose-Response Relationship, Drug , Furans/pharmacology , Immunization , Isoelectric Focusing , Leukocytes/drug effects , Lipoxygenase Inhibitors/pharmacology , Phospholipid Ethers/pharmacology , Platelet Activating Factor/antagonists & inhibitors , Rats , Triazoles/pharmacology
16.
Bone Marrow Transplant ; 13(3): 321-3, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8199573

ABSTRACT

We describe a case of cold agglutinin disease (CAD) following allogeneic bone marrow transplantation. This 36-year-old male developed CAD 3 weeks after allogeneic bone marrow transplantation for chronic myelogenous leukemia. Cyclosporin A and methotrexate had been administered to prevent graft-versus-host disease. Other agents administered included cytomegalovirus hyperimmune globulin and recombinant human G-CSF. Pericarditis preceded the development of CAD. The characterization of cold agglutinin (CA) was monoclonal IgM-kappa with anti-Pr antigen specificity, probably derived from the engrafted donor lymphocytes. The administration of prednisolone led to transient improvement. The CA titer decreased without further treatment 12 weeks after transplant.


Subject(s)
Anemia, Hemolytic, Autoimmune/etiology , Bone Marrow Transplantation/adverse effects , Adult , Anemia, Hemolytic, Autoimmune/diagnosis , Anemia, Hemolytic, Autoimmune/epidemiology , Cyclosporine/therapeutic use , Graft vs Host Disease/prevention & control , Humans , Incidence , Male , Methotrexate/therapeutic use , Prednisolone/therapeutic use , Transplantation, Homologous
17.
Bone Marrow Transplant ; 27(3): 307-10, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11277179

ABSTRACT

Eighty patients receiving hematological stem cell transplantation (HCT) with a preparative regimen consisting of total body irradiation (12.5 Gy), cyclophosphamide (4000 or 4500 mg/m2), and thiotepa (400 mg/m2) were evaluated for the development of cardiac toxicity. Patients in whom the pretransplant cumulative dose of anthracycline was more than or equal to 300 mg/m2 showed a lower left ventricular ejection fraction (EF) before HCT compared to patients with less than 300 mg/m2 (0.61 +/- 0.09 vs 0.67 +/- 0.06, P = 0.0010). Patients who had undergone more than or equal to six courses of chemotherapy showed a decreased EF before HCT compared to those after less than six courses (0.67 +/- 0.05 vs 0.63 +/- 0.09, P = 0.03). Three of seven patients (43%) whose pretransplant EF had been less than or equal to 0.55 developed severe cardiac toxicity, characterized by congestive heart failure (CHF) compared with none of 83 patients (0%) whose pretransplant EF had been more than 0.55 (P = 0.00026). Of the three patients who developed severe cardiac toxicity, two were given more than 300 mg/m2 of cumulative anthracycline and underwent 23 courses and six courses of chemotherapy, while the other patient received only two courses of chemotherapy with a total dose of 139 mg/m2 of anthracycline. These results indicate that an increased cumulative dose of anthracycline and number of chemotherapy treatments are correlated with a decrease of the EF and that the EF before HCT is useful for predicting the risk of cardiac complications for recipients who have received chemotherapy.


Subject(s)
Heart Failure/etiology , Hematopoietic Stem Cell Transplantation/adverse effects , Adolescent , Adult , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/toxicity , Cyclophosphamide/administration & dosage , Cyclophosphamide/toxicity , Dose-Response Relationship, Drug , Female , Heart Failure/diagnosis , Heart Failure/physiopathology , Hematologic Neoplasms/complications , Hematologic Neoplasms/therapy , Hematopoietic Stem Cell Transplantation/mortality , Humans , Male , Predictive Value of Tests , Prognosis , Retrospective Studies , Stroke Volume/physiology , Thiotepa/administration & dosage , Thiotepa/toxicity , Whole-Body Irradiation
18.
Bone Marrow Transplant ; 24(4): 359-63, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10467323

ABSTRACT

To clarify the role of hepatitis G virus (HGV) infection in liver dysfunction following allogeneic BMT, we examined cryopreserved serum samples from 33 patients who had a history of blood transfusions before BMT and whose serum samples had been stored periodically, before BMT, on day 100, and thereafter for the presence of HGV-RNA and hepatitis C virus (HCV)-RNA by reverse transcription polymerase chain reaction. Nineteen patients (58%) out of 33 were positive for HGV-RNA before BMT and 10 for HCV-RNA. All patients positive for HCV-RNA were also positive for HGV-RNA. Patients were divided into three groups according to their viral status before BMT; namely, the G+C+ group (n = 10), the G+C- group (n = 9) and the G-C- group (n = 14). Two patients in the G-C- group became positive for HGV-RNA after BMT. One patient in the G+C- group suffered an acute exacerbation of hepatitis, with GPT levels reaching over 1000 IU/l, 2 and 3 years after BMT, showing quite a different clinical course from those in the G+C- group. Excluding these three patients, GPT levels of the patients in the G+C+ group were significantly higher after day 100 and remained higher than those of patients in the G+C- and G-C- groups for at least 4 years. There were no significant differences in post-transplant GPT levels between the G+C- group and the G-C- group at any time point. Of the seven patients followed-up for 5 to 10 years, three patients became HGV-RNA-negative, while four remained positive. In the absence of HCV co-infection, the behavior of GPT values post transplant in patients with HGV infection did not differ from those without HGV infection. With respect to the patient who was G+C- and showed high values of GPT 2 and 3 years post transplant, we suspect that his liver dysfunction might have been caused by some unknown virus or etiology.


Subject(s)
Bone Marrow Transplantation/physiology , Flaviviridae , Hepatitis, Viral, Human/physiopathology , Hepatitis, Viral, Human/transmission , Liver Function Tests , Adolescent , Adult , Blood Specimen Collection , Blood Transfusion , Bone Marrow Transplantation/adverse effects , Cryopreservation , Female , Flaviviridae/isolation & purification , Follow-Up Studies , Hepacivirus/isolation & purification , Humans , Male , Middle Aged , Polymerase Chain Reaction , Postoperative Complications , RNA, Viral/blood , Retrospective Studies , Time Factors
19.
Am J Clin Pathol ; 101(3): 370-4, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8135199

ABSTRACT

The authors characterized antiplatelet membrane antibodies in the sera of patients with idiopathic thrombocytopenic purpura (ITP) and cirrhosis of the liver. Antibodies were detected in five of the 22 patients with chronic ITP and in none of the eight patients with cirrhosis of the liver. The authors report a patient with chronic ITP in complete remission. Antibody to platelet glycoproteins (GP), with molecular weights of 55 and 49 kDa, was detected in the serum. The patient's immunoglobulin G (IgG) alone could cause the aggregation of platelet-rich plasma. Anti-GPIIb/IIIa antibody (LJ-CP8) inhibited the aggregation of platelet-rich plasma induced by the patient's IgG in a dose-dependent manner. The F(ab')2 of the patient's IgG had a synergetic effect on the aggregation of PRP induced by adenosine 5-diphosphate. This demonstrates that in ITP, the binding of IgG via its fragment of antigen binding site portion may activate platelets.


Subject(s)
Autoantibodies/blood , Platelet Membrane Glycoproteins/immunology , Purpura, Thrombocytopenic, Idiopathic/immunology , Aged , Female , Humans , Immunoglobulin G/blood , Immunoglobulin G/immunology , Male , Platelet Aggregation/immunology , Purpura, Thrombocytopenic, Idiopathic/blood
20.
Peptides ; 16(2): 263-8, 1995.
Article in English | MEDLINE | ID: mdl-7784256

ABSTRACT

Fibronectin binds to platelet membrane glycoprotein (GP) IIb/IIIa in both an Arg-Gly-Asp (RGD)-dependent and -independent manner. The identification of an RGD-independent binding domain(s) that interacts with GPIIb/IIIa may be the key to understand the mechanism of thrombus formation. A recombinant fibronectin fragment containing the residues from Ile1359 to Ser1436 (lacking the RGD sequence) had been shown to bind to GPIIb/IIIa in a divalent cation- and activation-dependent manner. To identify a minimal peptide ligand that participates in the recognition of GPIIb/IIIa, we synthesized peptides extending this region, which consist of 12 amino acid residues in length and overlapping by six amino acids. We obtained evidence that two 12-residue peptide sequences from this region (residues 1371-1382 and 1377-1388) inhibit fibronectin binding to GPIIb/IIIa by interacting directly with this receptor, with IC50s of 95 +/- 16 and 104 +/- 19 microM, respectively. These peptides inhibited the binding of fibrinogen to GPIIb/IIIa, as well as ADP-induced platelet aggregation. These results indicate that an RGD-independent GPIIb/IIIa binding site in the cell binding domain of fibronectin was localized within the residues His1377-Ile1382.


Subject(s)
Fibronectins/chemistry , Fibronectins/metabolism , Oligopeptides , Peptide Fragments/pharmacology , Platelet Membrane Glycoproteins/metabolism , Adenosine Diphosphate/pharmacology , Amino Acid Sequence , Binding Sites , Binding, Competitive , Blood Platelets/metabolism , Fibrinogen/metabolism , Fibronectins/pharmacology , Humans , Molecular Sequence Data , Peptide Fragments/chemical synthesis , Peptide Fragments/chemistry , Platelet Aggregation/drug effects
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