14 results on '"Yamaki, T."'
Search Results
2. Scoping Review on the Diagnosis, Prognosis, and Treatment of Pediatric Disorders of Consciousness.
- Author
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Molteni E, Canas LDS, Briand MM, Estraneo A, Font CC, Formisano R, Fufaeva E, Gosseries O, Howarth RA, Lanteri P, Licandro GI, Magee WL, Veeramuthu V, Wilson P, Yamaki T, and Slomine BS
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- Adolescent, Humans, Female, Child, Coma, Prognosis, Randomized Controlled Trials as Topic, Consciousness, Consciousness Disorders diagnosis, Consciousness Disorders therapy
- Abstract
Background and Objectives: Comprehensive guidelines for the diagnosis, prognosis, and treatment of disorders of consciousness (DoC) in pediatric patients have not yet been released. We aimed to summarize available evidence for DoC with >14 days duration to support the future development of guidelines for children, adolescents and young adults aged 6 months-18 years., Methods: This scoping review was reported based on Preferred Reporting Items for Systematic reviews and Meta-Analyses-extension for Scoping Reviews guidelines. A systematic search identified records from 4 databases: PubMed, Embase, Cochrane Library, and Web of Science. Abstracts received 3 blind reviews. Corresponding full-text articles rated as "in-scope" and reporting data not published in any other retained article (i.e., no double reporting) were identified and assigned to 5 thematic evaluating teams. Full-text articles were reviewed using a double-blind standardized form. Level of evidence was graded, and summative statements were generated., Results: On November 9, 2022, 2,167 documents had been identified; 132 articles were retained, of which 33 (25%) were published over the past 5 years. Overall, 2,161 individuals met the inclusion criteria; female patients were 527 of 1,554 (33.9%) cases included, whose sex was identifiable. Of 132 articles, 57 (43.2%) were single case reports and only 5 (3.8%) clinical trials; the level of evidence was prevalently low (80/132; 60.6%). Most studies included neurobehavioral measures (84/127; 66.1%) and neuroimaging (81/127; 63.8%); 59 (46.5%) were mainly related to diagnosis, 56 (44.1%) to prognosis, and 44 (34.6%) to treatment. Most frequently used neurobehavioral tools included the Coma Recovery Scale-Revised, Coma/Near-Coma Scale, Level of Cognitive Functioning Assessment Scale, and Post-Acute Level of Consciousness scale. EEG, event-related potentials, structural CT, and MRI were the most frequently used instrumental techniques. In 29/53 (54.7%) cases, DoC improvement was observed, which was associated with treatment with amantadine., Discussion: The literature on pediatric DoCs is mainly observational, and clinical details are either inconsistently presented or absent. Conclusions drawn from many studies convey insubstantial evidence and have limited validity and low potential for translation in clinical practice. Despite these limitations, our work summarizes the extant literature and constitutes a base for future guidelines related to the diagnosis, prognosis, and treatment of pediatric DoC., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.)
- Published
- 2023
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3. Improved detectability of thromboses of the lower limb using low kilovoltage computed tomography.
- Author
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Sasaki T, Fujimoto Y, Ishitoya S, Nabaa B, Watanabe N, Yamaki T, and Takahashi K
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- Aged, Female, Humans, Japan, Male, Middle Aged, Radiographic Image Enhancement methods, Retrospective Studies, Lower Extremity blood supply, Phlebography methods, Thrombosis diagnostic imaging, Tomography, X-Ray Computed methods, Venous Thrombosis diagnosis
- Abstract
To determine the utility of low kilovoltage computed tomographic venography (CTV) for the detection of deep venous thrombus in the lower limbs.Twenty-one thrombi in 19 enrolled patients were investigated in this retrospective study. Patients were initially scanned using CTV at 100 kVp, at the femur level, followed by an immediate switch to 80 kVp. We assessed the CT values of thrombi and veins and performed subjective evaluation for detecting thrombi using a 5-point scoring system: 1, unable to evaluate due to noise or artifacts; 2, equivocal venous thrombus; 3, possible venous thrombus; 4, probable venous thrombus; and 5, definite venous thrombus.Venous density on 100-kVp images (mean ± SD [standard deviation]: 122 ± 23 HU, 95% confidence interval [CI]: 111-133 Hounsfield unit [HU]) was significantly lower than that on 80-kVp images (136 ± 24 HU, 95% CI: 125-147 HU, P < .001). There was no significant difference in thrombi between 100-kVp images (55 ± 14 HU, 95% CI: 49-61 HU) and 80-kVp images (57 ± 16, 95% CI: 50-64 HU, P = .168). The thrombus to vein ratio on 100-kVp images (0.47 ± 0.20, 95% CI: 0.39-0.56) was significantly higher than that on 80-kVp images (0.44 ± 0.16, 95% CI: 0.37-0.51, P = .048). The mean 5-point score was significantly higher on the 80-kVp images (4.76) than on the 100-kVp images (4.45, P = .016).Lower kilovoltage CTV significantly improved thrombotic to venous contrasts in the lower limbs.
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- 2018
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4. Endoscopic Endonasal Repair of Isolated Medial Orbital Wall Fracture With Balloon Technique.
- Author
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Soejima K, Kashimura T, Yamaki T, Sakurai H, and Nakazawa H
- Subjects
- Adolescent, Adult, Aged, Diplopia etiology, Enophthalmos etiology, Ethmoid Sinus, Female, Humans, Male, Middle Aged, Nasal Cavity, Natural Orifice Endoscopic Surgery instrumentation, Operative Time, Orbital Fractures complications, Orbital Fractures diagnostic imaging, Tomography, X-Ray Computed, Natural Orifice Endoscopic Surgery methods, Orbital Fractures surgery
- Abstract
Endonasal endoscopic repair of medial orbital wall fractures is minimally invasive and benefits the patients. The authors describe the authors' modified balloon technique, which allows longer support of the orbital wall. From October 2010 through January 2016, the author repaired 9 isolated medial wall fractures by this method. Five patients were diagnosed as having enophthalmos of greater than 2 mm, and 6 patients had persistent diplopia before the operation. The herniated orbital contents that filled the anterior ethmoidal sinus were gently reduced with a 4-mm-diameter 0° sinus endoscope. Then a posterior nasal cavity balloon (Type B # 32014, KOKEN Co, Japan) was inserted into the ethmoidal sinus and filled with normal saline. The inflation tube of the balloon was sutured to the nasal cavity wall with absorbable sutures. After checking the status of the balloon, the inflation tube was ligated and cut so that it could be hidden inside the nasal cavity. The balloon was removed on an outpatient basis 6 to 7 weeks after the surgery. In this series, the mean inflation volume of the balloon was 1.6 mL, the mean period of leaving the balloon in place was 5.7 weeks, and the mean operative time was 38.6 minutes.Resolution of the preoperative diplopia and enophthalmos was achieved in all 9 patients, and there was no recurrence of prolapse of the orbital contents. This method allows leaving the balloon in place for a long period of time without interfering with daily life, which reduces the risk of rebulging of the orbital contents.
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- 2017
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5. Administration of a peroxynitrite decomposition catalyst into the bronchial artery attenuates pulmonary dysfunction after smoke inhalation and burn injury in sheep.
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Hamahata A, Enkhbaatar P, Lange M, Yamaki T, Nakazawa H, Nozaki M, Sakurai H, Traber LD, and Traber DL
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- Acute Lung Injury metabolism, Acute Lung Injury pathology, Acute Lung Injury physiopathology, Animals, Bronchial Arteries metabolism, Bronchial Arteries physiopathology, Female, Lung metabolism, Lung pathology, Peroxynitrous Acid antagonists & inhibitors, Peroxynitrous Acid pharmacology, Sheep, Smoke Inhalation Injury metabolism, Smoke Inhalation Injury pathology, Smoke Inhalation Injury physiopathology, Time Factors, Acute Lung Injury drug therapy, Capillary Permeability drug effects, Lung physiopathology, Peroxynitrous Acid metabolism, Smoke Inhalation Injury drug therapy
- Abstract
Reactive nitrogen species such as peroxynitrite play a significant role in burn and smoke inhalation injury. The bronchial circulation increases more than 10-fold in response to this combination injury. We hypothesized that direct delivery of low-dose WW-85, a peroxynitrite decomposition catalyst, into the bronchial artery would attenuate burn- and smoke inhalation-induced acute lung injury. In adult female sheep (n = 17), the bronchial artery was cannulated in preparation surgery. After a 5- to 7-day recovery period, sheep were subjected to a burn (40% total body surface area, third degree) and inhalation injury (48 breaths of cotton smoke, <40°C). The animals were divided into three groups following the injury: (i) WW-85 group: 1 h after injury, WW-85 (0.002 mg/kg per hour) was continuously infused into the bronchial artery, n = 5; (ii) control group: 1 h after injury, an equivalent amount of saline was injected into the bronchial artery, n = 6; (iii) sham group: no injury, no treatment, same operation and anesthesia, n = 6. All animals were mechanically ventilated and fluid resuscitated equally. In the control group, the injury induced a severe deterioration of pulmonary oxygenation and shunting and an increase in pulmonary microvascular permeability toward sham. The injury was further associated with an increase in reactive nitrogen species in lung tissues of the control group. All these alterations were significantly attenuated in the WW-85 group. We demonstrated that a low dosage of WW-85 directly administered into the bronchial artery attenuated pulmonary dysfunction to the same extent as higher systemically administered doses in previous experiments. Our data strongly suggest that local airway production of peroxynitrite contributes to pulmonary dysfunction following smoke inhalation and burn injury.
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- 2012
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6. Antidiabetic drug voglibose is protective against ischemia-reperfusion injury through glucagon-like peptide 1 receptors and the phosphoinositide 3-kinase-Akt-endothelial nitric oxide synthase pathway in rabbits.
- Author
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Iwasa M, Kobayashi H, Yasuda S, Kawamura I, Sumi S, Yamada Y, Shiraki T, Yamaki T, Ushikoshi H, Aoyama T, Nishigaki K, Takemura G, Fujiwara T, Fujiwara H, and Minatoguchi S
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- Animals, Arginine metabolism, Arginine pharmacology, Decanoic Acids, Glucagon-Like Peptide 1 metabolism, Glucagon-Like Peptide 1 pharmacology, Glucagon-Like Peptide-1 Receptor, Heart drug effects, Heart physiopathology, Hydroxy Acids, Hypoglycemic Agents metabolism, Inositol analogs & derivatives, Male, Myocardial Infarction metabolism, Myocardial Infarction physiopathology, Myocardial Ischemia metabolism, Myocardium metabolism, Nitric Oxide Synthase antagonists & inhibitors, Nitric Oxide Synthase pharmacology, Nitric Oxide Synthase Type III, Phosphotransferases metabolism, Phosphotransferases pharmacology, Rabbits, Receptors, Glucagon, alpha-Glucosidases metabolism, alpha-Glucosidases pharmacology, Hypoglycemic Agents pharmacology, Nitric Oxide Synthase metabolism, Proto-Oncogene Proteins c-akt metabolism, Reperfusion Injury metabolism
- Abstract
Glucagon-like peptide 1 (GLP-1) reportedly exerts a protective effect against cardiac ischemia. We hypothesized that the alpha-glucosidase inhibitor voglibose, an unabsorbable antidiabetic drug with cardioprotective effects, may act through stimulation of GLP-1 receptors. The results of the present study suggest oral administration of voglibose reduces myocardial infarct size and mitigates cardiac dysfunction in rabbits after 30 minutes of coronary occlusion and 48 hours of reperfusion. Voglibose increased basal and postprandial plasma GLP-1 levels and reduced postprandial plasma glucose levels. The infarct size-reducing effect of voglibose was abolished by treatment with exendin(9-39), wortmannin, Nomega-nitro-L-arginine methylester, or 5-hydroxydecanoate), which inhibit GLP-1 receptors, phosphoinositide 3-kinase, nitric oxide synthase, and K(ATP) channels, respectively. Western blot analysis showed that treatment with voglibose upregulated myocardial levels of phospho-Akt, phosphoendothelial nitric oxide synthase after myocardial infarction. The upregulation of phospho-Akt was inhibited by exendin(9-39) and wortmannin. These findings suggest that voglibose reduces myocardial infarct size through stimulation of GLP-1 receptors, activation of the phosphoinositide 3-kinase-Akt-endothelial nitric oxide synthase pathways, and the opening of mitochondrial K(ATP) channels. These findings may provide new insight into therapeutic strategies for the treatment of patients with coronary artery disease.
- Published
- 2010
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7. Postinfarct treatment with oxytocin improves cardiac function and remodeling via activating cell-survival signals and angiogenesis.
- Author
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Kobayashi H, Yasuda S, Bao N, Iwasa M, Kawamura I, Yamada Y, Yamaki T, Sumi S, Ushikoshi H, Nishigaki K, Takemura G, Fujiwara T, Fujiwara H, and Minatoguchi S
- Subjects
- Animals, Blood Pressure drug effects, Blood Pressure physiology, Cyclin D1 metabolism, Disease Models, Animal, Echocardiography, Extracellular Signal-Regulated MAP Kinases metabolism, Heart drug effects, Heart physiopathology, Heart Rate drug effects, Heart Rate physiology, Male, Matrix Metalloproteinase 1 metabolism, Microvessels anatomy & histology, Microvessels metabolism, Myocardial Infarction pathology, Myocardial Infarction physiopathology, Myocardium metabolism, Myocardium pathology, Nitric Oxide Synthase Type III metabolism, Oxytocin pharmacology, Phosphorylation drug effects, Platelet Endothelial Cell Adhesion Molecule-1 metabolism, Proto-Oncogene Proteins c-akt metabolism, Rabbits, Receptors, Oxytocin metabolism, STAT3 Transcription Factor metabolism, Stroke Volume drug effects, Stroke Volume physiology, Vascular Endothelial Growth Factor A metabolism, Ventricular Dysfunction, Left drug therapy, Ventricular Dysfunction, Left pathology, Ventricular Dysfunction, Left physiopathology, Ventricular Function, Left physiology, Ventricular Remodeling physiology, Myocardial Infarction drug therapy, Neovascularization, Physiologic drug effects, Oxytocin therapeutic use, Signal Transduction drug effects, Ventricular Function, Left drug effects, Ventricular Remodeling drug effects
- Abstract
Background: We investigated whether postinfarct treatment with oxytocin (OT) improves left ventricular (LV) function and remodeling via cardiac repair of myocardial ischemia-reperfusion injury., Methods and Results: Experiments were performed with 30 minutes of coronary occlusion and 2 or 14 days of reperfusion rabbit model of myocardial infarction. LV function and remodeling were significantly improved in the OT group. The infarct size was significantly reduced in the OT group. The number of CD31-positive microvessels was increased significantly in the OT group. There were no Ki67-positive myocytes in either group. The expression of the OT receptor, phosphorylated (p)-Akt protein kinase, p-extracellular signal-regulated protein kinase, p-enodthelial NO synthase, p-signal transducer and activator of transcription 3, vascular endothelial growth factor, B-cell lymphoma 2, and matrix metalloproteinase-1 (MMP-1) were markedly increased in the OT group days 2 and 14 post myocardial infarction., Conclusions: Postinfarct treatment with OT reduces myocardial infarct size and improves LV function and remodeling by activating OT receptors and prosurvival signals and by exerting antifibrotic and angiogenic effects through activation of MMP-1, endothelial NO synthase, and vascular endothelial growth factor. These findings provide new insight into therapeutic strategies for ischemic heart disease.
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- 2009
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8. Monitoring the changes in intraparenchymatous venous pressure to ascertain flap viability.
- Author
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Sakurai H, Nozaki M, Takeuchi M, Soejima K, Yamaki T, Kono T, Fukaya E, and Yamamoto Y
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- Adolescent, Adult, Aged, Catheterization, Peripheral, Female, Humans, Laser-Doppler Flowmetry, Male, Microsurgery, Middle Aged, Monitoring, Physiologic, Veins, Venous Insufficiency etiology, Venous Thrombosis complications, Blood Pressure Determination instrumentation, Surgical Flaps blood supply, Tissue Survival physiology, Venous Insufficiency diagnosis, Venous Pressure, Venous Thrombosis diagnosis
- Abstract
Background: Disruption of venous outflow can lead to tissue necrosis. Thrombosis of a venous channel at the coaptation site in instances of free tissue transfer could cause death of the transplanted tissues. Although various techniques have been used to monitor the viability of transferred tissues, there has been no technique designed specifically to check the flow within and the patency of the venous channel. The authors have devised an approach with which to monitor the changes in venous pressure in a composite tissue transferred by means of microsurgical technique for bodily reconstruction., Methods: The status of the venous system in various composite tissue grafts was monitored at the time of surgery or for 3 days after the completion of surgery by placing a small-caliber catheter in the vein within the transferred tissue. A total of 52 patients participated in the study., Results: The venous pressure noted in grafts with a patent venous channel remained constant within a range between 0 and 35 mmHg. Venous insufficiency was detected in three of the 52 cases, with unmistakable findings of an elevated venous pressure of over 50 mmHg., Conclusions: The technique of measuring the venous pressure by means of an indwelling venous catheter to monitor changes was found to accurately assess the patency of the venous channel and, by inference, the viability of the transferred tissue. No morbidity was associated with the technique.
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- 2007
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9. Validation of collateral fractional flow reserve by myocardial perfusion imaging.
- Author
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Matsuo H, Watanabe S, Kadosaki T, Yamaki T, Tanaka S, Miyata S, Segawa T, Matsuno Y, Tomita M, and Fujiwara H
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- Aged, Aged, 80 and over, Angina Pectoris complications, Angina Pectoris physiopathology, Angioplasty, Balloon, Coronary, Aorta, Blood Flow Velocity, Blood Pressure, Coronary Angiography, Coronary Stenosis complications, Coronary Stenosis physiopathology, Coronary Stenosis surgery, Coronary Vessels diagnostic imaging, Electrocardiography, Humans, Linear Models, Male, Middle Aged, Predictive Value of Tests, Radionuclide Imaging, Reproducibility of Results, Severity of Illness Index, Technetium Tc 99m Sestamibi, Angina Pectoris diagnosis, Collateral Circulation, Coronary Circulation, Coronary Stenosis diagnosis
- Abstract
Background: Collateral fractional flow reserve (FFR(coll)) is an index to quantify collateral blood flow, derived from coronary pressure measurements. Although well defined theoretically, its direct validation by myocardial perfusion imaging has not been established so far. Validating this index by myocardial perfusion imaging is the main aim of this study., Methods and Results: Twenty-four consecutive patients with stable angina and single left anterior descending artery stenosis underwent simultaneous measurement of aortic pressure (P(a)), coronary wedge pressure (P(w)), and central venous pressure (P(v)) during balloon inflation. FFR(coll) was calculated and compared with the extent and severity of the defect during coronary occlusion using (99m)Tc-sestamibi imaging at balloon inflation of the respective coronary artery. Although the pressure-derived collateral indexes (P(w), P(w)/P(a), and FFR(coll)) ranged widely, they were closely correlated with extent and severity scores of the nuclear occlusion images and superior to the ECG for that purpose. Of all parameters, FFR(coll) correlated best with the severity score at imaging (r=-0.88), followed by the P(w)/P(a) ratio (r=-0.74) or P(w) alone (r=-0.69)., Conclusions: FFR(coll), calculated from coronary pressure during balloon occlusion, is highly correlated with the extent and severity of the defect at myocardial perfusion of the territory of the occluded artery and can be used for quantitative assessment of collateral blood flow in conscious humans.
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- 2002
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10. Value of repeat angiography in patients with spontaneous subcortical hemorrhage.
- Author
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Hino A, Fujimoto M, Yamaki T, Iwamoto Y, and Katsumori T
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- Adolescent, Adult, Aged, Aged, 80 and over, Cerebral Hemorrhage diagnostic imaging, Cerebral Hemorrhage etiology, Cerebral Hemorrhage surgery, Child, Evaluation Studies as Topic, Female, Follow-Up Studies, Hematoma surgery, Humans, Intracranial Arteriovenous Malformations complications, Intracranial Arteriovenous Malformations diagnostic imaging, Intracranial Arteriovenous Malformations surgery, Magnetic Resonance Imaging, Male, Middle Aged, Cerebral Angiography standards, Cerebral Hemorrhage diagnosis
- Abstract
Background and Purpose: Neuroradiological investigations do not disclose a source of bleeding in some patients with spontaneous subcortical hemorrhage. These patients may harbor undetected vascular malformations and may be at risk of rebleeding in the future. We investigated patients with subcortical hemorrhage with use of repeat angiography and MRI to determine the incidence of occult vascular malformations and the risk of bleeding during follow-up., Methods: We reviewed a consecutive series of 137 patients with subcortical hemorrhage during a 10-year period (June 1987 through June 1997). If the patient was <65 years old and the first angiogram and/or MRI did not show a source of bleeding, repeat angiography was recommended. All angiographic and MRI studies were reviewed. The relationship between the identified bleeding source and clinical variables such as patient age, sex, and history of hypertension and the size and location of the hematoma were examined., Results: One hundred seven patients (78%) underwent angiography on admission, 10 (7%) had immediate surgery for hematoma without angiography, and 20 (15%) had neither angiography nor surgery. Overall, an etiology for the hemorrhage was found in 55 cases (40%). Vascular malformations were common in young patients without preexisting hypertension. A second angiogram was obtained in 22 patients, and 4 arteriovenous malformations were demonstrated. Rebleeding at the site of the initial hemorrhage was not observed after a mean follow-up of 68 months., Conclusions: Angiography performed acutely after hemorrhage may not demonstrate vascular malformations. Consideration should be given to repeat angiography in patients who do not have a specific cause for hemorrhage.
- Published
- 1998
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11. Chronological positron emission tomographic study of severe diffuse brain injury in the chronic stage.
- Author
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Yamaki T, Yoshino E, Fujimoto M, Ohmori Y, Imahori Y, and Ueda S
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- Adult, Brain Chemistry, Brain Injuries metabolism, Brain Injuries physiopathology, Case-Control Studies, Cerebrovascular Circulation, Chronic Disease, Follow-Up Studies, Glucose metabolism, Humans, Oxygen Consumption, Prognosis, Brain Injuries diagnostic imaging, Tomography, Emission-Computed
- Abstract
Cerebral blood flow and metabolism were investigated in five patients with severe diffuse brain injury in the chronic stage, using positron emission tomography (PET). Regional cerebral blood flow, regional oxygen extraction fraction, regional cerebral blood volume, regional cerebral metabolic rate for oxygen, and regional cerebral metabolic rate for glucose were measured bilaterally in the frontal, temporal, occipital, and parietal gray matter, as well as the white matter of the centrum semiovale. In 4 of 5 patients, a follow-up PET study was also performed. In three cases, below-normal regional cerebral blood flow and regional cerebral metabolic rate for oxygen values accompanied by above-normal regional oxygen extraction fraction values, as well as low metabolism, were demonstrated in the initial PET studies. In two of three cases, clinical improvements were observed, and follow-up PET data also improved. These findings suggest that chronological PET studies may be able to assess quantitatively clinical improvements in patients with diffuse brain injury.
- Published
- 1996
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12. CT demonstration of massive cerebral air embolism from pulmonary barotrauma due to cardiopulmonary resuscitation.
- Author
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Yamaki T, Ando S, Ohta K, Kubota T, Kawasaki K, and Hirama M
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- Aged, Barotrauma diagnostic imaging, Embolism, Air etiology, Humans, Intracranial Embolism and Thrombosis etiology, Male, Barotrauma etiology, Embolism, Air diagnostic imaging, Intracranial Embolism and Thrombosis diagnostic imaging, Resuscitation adverse effects, Tomography, X-Ray Computed
- Abstract
A 77-year-old man with loss of consciousness, circulatory collapse, and apnea caused by myocardial infarction underwent cardiopulmonary resuscitation with intratracheal intubation and manual bag ventilation. Computed tomography of the head demonstrated massive air embolism in the entire cerebral circulation. The patient was diagnosed as brain dead the next day. Demonstration of massive cerebral air embolism on head CT is presented.
- Published
- 1989
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13. Microvascular responses to norepinephrine and vasopressin during halothane anesthesia in the rat.
- Author
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Yamaki T, Baez S, Feldman SM, Gootman PM, and Orkin LR
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- Animals, Blood Pressure drug effects, Brain, Electric Stimulation, Electrodes, Implanted, Male, Rats, Arteries drug effects, Arterioles drug effects, Halothane, Norepinephrine pharmacology, Vasopressins pharmacology
- Abstract
This experiment was designed to determine the microvascular responses to the two known naturally occurring vasoconstrictors, norepinephrine (NE) and vasopressin, at known levels of central vasomotor activity before, during and after halothane anesthesia. The responses to topical application of NE and vasopressin were studied in the microvasculature of the mesentery and cremaster muscle, using microscopic methods. Neural (CNS) stimulation was accomplished through electrodes chronically implanted in vasoactive sites of the forebrain and midbrain. The increase in blood pressure in response to CNS stimulation was decreased during halothane anesthesia (32.4 +/- 5.4 per cent before and 24.7 +/- 6.1 per cent during; P less than 0.001). There was no significant change in the steady-state diameter of the microvasculature under study during or after halothane anesthesia. Marked abatement of arteriolar vasoconstriction in response to CNS stimulation was seen prior to halothane. However, the same target vessel showed increased constriction in response to topically applied NE (from 32.3 +/- 4.7 to 53.2 +/- 7.8 per cent; P less than 0.01) during halothane anesthesia. By contrast, the response to vasopressin decreased (from 42.4 +/- 5.7 to 1.0 +/- 6 per cent; P less than 0.001) with halothane. The precise mechanism(s) underlying the described hypersensitivity to NE and hyposensitivity to vasopressin in the same vascular structure during halothane anesthesia remains undetermined.
- Published
- 1978
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14. HEMODYNAMIC EFFECTS OF HYPERBARIC OXYGENATION IN EXPERIMENTAL ACUTE MYOCARDIAL INFARCTION.
- Author
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KUHN LA, KLINE HJ, WANG M, YAMAKI T, and JACOBSON JH 2nd
- Subjects
- Animals, Dogs, Aorta, Blood Pressure, Electrocardiography, Heart Function Tests, Hemodynamics, Hyperbaric Oxygenation, Mortality, Myocardial Infarction, Pathology, Research
- Published
- 1965
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