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Biomedical subjects

H Fukuda

Publications and source records attributed to H Fukuda.

At least 487 records · Page 27Linked to original sources

[Normal CBF values by the ARG method using IMP SPECT: comparison with a conventional microsphere model method].

N-isopropyl-p[123I]iodoamphetamine (IMP) has been used as a flow tracer for SPECT, and measurement of cerebral blood flow (CBF) using IMP has been performed by conventional microsphere model method (MS method). Recently, the ARG method for measuring CBF by using IMP with one SPECT scan and one point blood sampling has been developed. This method was based on two-compartment model. In the present study, normal CBF values were measured in ten male healthy subjects (mean age +/- S.D.: 29.8 +/- 6.01, age range: 23-41) by the ARG and the MS methods. The mean CBF values (+/- S.D.) for the ARG method in which the Vd value was assumed to be 50 ml/ml were 41.7 +/- 9.4, 31.1 +/- 5.0, 40.7 +/- 9.7, 41.5 +/- 10.0, 38.2 +/- 9.2, 39.0 +/- 9.4, 41.9 +/- 10.6, 38.7 +/- 8.0 and 30.0 +/- 7.7 ml/100 ml/min in the cerebellum, pons, thalamus, basal ganglia, frontal, temporal, parietal, occipital lobe cortex and centrum semiovale, respectively. The mean CBF values for the MS method were 46.8 +/- 8.4, 37.5 +/- 5.6, 45.8 +/- 8.6, 46.5 +/- 8.9, 43.7 +/- 8.3, 44.4 +/- 8.7, 46.8 +/- 9.3, 44.3 +/- 7.3 and 36.3 +/- 8.1 ml/100 ml/min, respectively. The mean CBF values in the cerebral cortex region for the ARG method were lower than those previously reported by PET. This would be caused by low first-pass extraction fraction of IMP compared with oxygen-15 labeled water. The mean CBF values for the MS method were higher than those for the ARG method against previous studies. As reasons for this, errors in estimation of the SPECT brain counts at 8 min in the MS method were considered.

Adult↗

Hypoperfusion in the limbic system and prefrontal cortex in depression: SPECT with anatomic standardization technique.

UNLABELLED: Depression is a common psychiatric illness, and several reports have described cerebral blood flow (CBF) abnormalities on SPECT studies in affected patients. However, because region of interest analyses were used to determine significant CBF changes in these studies, there were methodological limitations. Therefore, we investigated CBF distribution abnormalities in depression on a pixel-by-pixel basis using SPECT and an anatomic standardization technique that has been commonly used for PET activation studies. METHODS: Eleven patients with unipolar depression, six patients with bipolar depression and nine age-matched normal control subjects underwent HMPAO brain SPECT studies. The radioactivities of SPECT images for each subject were globally normalized to 100 counts/pixel. Then, each SPECT image was transformed for standard brain anatomy using a computerized Human Brain Atlas system. For each group, the mean and variance images were calculated from the standardized anatomic SPECT images, and group comparisons were performed on a pixel-by-pixel basis. RESULTS: Significant decreases in CBF in the prefrontal cortices, limbic systems and paralimbic areas were observed in both depression groups compared with the normal control group. CONCLUSION: Decreases in CBF in these regions may be related to impaired attention as well as cognitive and emotional responses, which have been recognized as usual symptoms in depression. The anatomic standardization technique promises to be useful for group comparison analysis of brain SPECT on a pixel-by-pixel basis for individual neurological and psychiatric diseases.

Aged↗

[Regional distribution of the muscarinic cholinergic receptor in the human brain studied with 11C-benztropine and PET using an anatomical standardization technique].

We measured regional distribution of the muscarinic cholinergic receptor in the normal human brain with 11C-benztropine (BZT) and positron emission tomography (PET) using an anatomical standardization technique. Seven normal volunteers who gave informed consents were involved in this study. Immediately after intravenous injection of 11C-BZT into the subjects, we started dynamic PET scanning and serial frequent arterial blood sampling. Analyses of plasma metabolites were also performed at selected time points and plasma time activity curves (TAC) of unmetabolized ligand were generated. From these PET and TAC data, we obtained Patlak plot slope calculation images. Using the HBA (human brain atlas) system, the Patlak plot slope calculation image of each subject was transformed into the shape of the standard brain. Mean and standard deviation (SD) calculation images were generated from those anatomically standardized images. On these mean and SD images, we placed regions of interest which were previously outlined on a MR image of the standard brain. From those data, we found the highest receptor distribution in the striatum and occipital cortex, as well as high distribution in the frontal, parietal, and temporal cortices, which were consistent with previous reports. These results suggested that anatomical standardization of PET receptor images with 11C-BZT will be useful for delineating the physiological or pathological alterations of the muscarinic cholinergic receptor in the human brain.

Adolescent↗

[A case of diffuse fasciitis and its MRI findings].

A 36-year-old woman with diffuse fasciitis and her MRI findings are reported. The patient developed pain and swelling in the calves, right forearm, and left arm, predominantly in the right calf muscle. Her body temperature was 38.4 degrees C, the ESR 104 mm/2 hours and white blood cell count 8,000/microliter without eosinophilia. The fascia and muscle were biopsied from her right calf. The light microscopy showed that the fascia was thickened and infiltrated with mononuclear cells with no eosinophils, mostly in perivascular areas. The muscle fibers were spared. MRI of legs revealed marked hyperintensities on T2 and mild hyperintensities on T1-weighted images in the fascia, superficial flexor muscles, especially soleus muscle, and Achilles tendons. Moderate dose of prednisolone was very effective and the abnormal signals on MRI almost disappeared within a month. T2 weighted MRI was very useful to detect the lesions and to evaluate the course of diffuse fasciitis.

Adult↗

[Emergency internal carotid artery ligation using near infrared spectroscopy].

We anesthetized a patient who received an emergency internal carotid artery ligation. Regional cerebral oxygen saturation (rSO2) was measured with near infrared spectroscopy (NIRS) during the whole anesthetic course. The sensor was placed on the left forehead of the patient. Decrease in blood pressure was reflected in the decrease in rSO2. The rSO2 was not altered by internal carotid ligation. However, cerebral infarction in the middle cerebral artery region, the onset of which remained unclear, was revealed postoperatively, regardless of a stable rSO2 during the operation. This monitor may provide useful information regarding the cerebral circulation during the operation in such a case as the present one, but this monitor reflects only the oxygenation of the region on which the sensor was placed. Thus, we should keep in mind the limitation in detecting cerebral dysfunction using NIRS.

Anesthesia, General↗

[Clinical evaluation of a new programmable syringe infusion pump].

A new programmable syringe infusion pump, Auto Syringe Model AS 40 A, was evaluated for infusion of muscle relaxants, vasodilators and opioids in 4 surgical patients. Every drug mentioned above was easily adjusted according to surgical requirement in these patients. Auto Syringe Model AS40A is light and compact. Its major advantages lie in the mechanisms for delivery of a bolus dose and automated delivery of intermittent doses, automatic rate calculation, and the applicability to various sizes of syringes. Auto Syringe Model AS40A was found to be very useful for intravenous infusion of drugs.

Adult↗

[Normal cerebral perfusion of 99mTc-ECD brain SPECT--evaluation by an anatomical standardization technique].

A single photon emitter labeled tracer, 99mTc-ethyl cysteinate dimer (99mTc-ECD), has now been used for rCBF studies with SPECT. However, normal distribution pattern of this agent in the brain still remains unclear. Therefore, the specific purpose of this study was to investigate the normal distribution pattern of 99mTc-ECD SPECT image. Regional cerebral distribution was measured with SPECT and 984 +/- 17 MBq of 99mTc-ECD in ten normal subjects. During the SPECT measurement, subjects were placed comfortably in a supine position with their eyes closed. Each SPECT image was anatomically standardized using a computerized brain atlas system of Roland et al. (HBA: Human Brain Atlas) and X-CT image. Anatomically standardized SPECT images were globally normalized to 100 count/voxel. Then, the mean and SD images of brain SPECT were calculated voxel-by-voxel basis. The highest radioactivity was found in the medial aspect of the occipital lobe. The results indicate that the normal distribution pattern of 99mTc-ECD in the human brain may be not simply reflect the regional cerebral blood flow.

Adult↗

[A new embolic material: super absorbent polymer (SAP) microsphere and its embolic effects].

SAP-Microsphere (sodium acrylic acid-vinyl alcohol copolymer) has the ability to absorb fluids within a few minutes and increase its diameter. Its diameter can also be calibrated. The diameters in ionic contrast material and human serum are 2.1 and 3.5 times larger, respectively, than the original size. It can pass through a microcatheter with an ionic contrast material, and swells at the occluding point into the desired size. It can be recognized under fluoroscopy due to its absorption of contrast material. A total of 10 rabbit kidney embolizations were done followed by resection in 1-14 weeks. Recanalization was absent in all cases. No adhesion to the perirenal tissue was found. Limited reactive change in endothelial cells was found at one week. No changes in the smooth muscle layer were found at any time during the study. Limited infiltration of neutrophil cells was found in perivascular tissue within a period of one week. SAP-Microspheres maintained their spherical shape during a 14-week period. Extensive fibrosis and calcification were found after 4 weeks. SAP-Microspheres are promising as an embolic agent to obtain satisfactory results of embolization therapy.

Absorption↗

[Swyer-James syndrome with pneumomediastinum and subcutaneous emphysema due to bronchial asthma].

A 24-year-old woman was admitted to our hospital due to moderate asthmatic attacks. Dyspnea and hypoxemia progressed gradually despite medication. A chest roentgenogram revealed left unilateraly hyperlucency with pneumomediastiumn and subcutaneous emphysema. Swyer-James syndrome was diagnosed. Several cases of Swyer-James syndrome with bronchial asthma airway hyperresponsiveness have been reported, but we know of no reports of Swyer-James syndrome with pneumomediastinum and subcutaneous emphysema due to prolonged asthmatic attacks. Pneumomediastinum and subcutaneous emphysema may be caused by abnormally high pressures in the bronchial lumen and alveolar space during asthmatic attacks, because the emphysematous lesion may be structurally weak.

Adult↗

[Analysis of contributing factors with high renal uptake of 99mTc-MDP after anti-cancer chemotherapy including cisplatin].

We studied the effect of anti-cancer chemotherapy including cis-platin (CDDP) on renal high uptake of 99mTc-MDP using renal accumulation index (RAI) which was defined as a ratio of the densities between kidneys and lumbar bodies. We analyzed 21 cases who received bone scintigraphy within 30 days after chemotherapy. High RAIs were observed in 15 cases (71.4%). We compared the relationship between the RAI and time interval of CDDP administration and bone scintigraphy, total dose of CDDP, BUN and age. High RAIs were inversely related to the time interval and no patient showed high RAI when bone scintigraphy were studied later than 17 days after chemotherapy. BUN level were related to RAI. But, dose of CDDP and ages were unlikely responsible for the RAI values in this study. We summarized that high renal uptake of 99mTc-MDP was likely to be due to short time interval after chemotherapy.

Adult↗

[Effectiveness of the radioactive strontium (89Sr) chloride agent, SMS.2P for pain palliation in patients with metastatic bone tumor in phase III multicenter clinical trial].

The phase III clinical trial of strontium-89 chloride agent (SMS.2P) was performed in 90 patients with painful bone metastases secondary to prostate (53), breast (18) and other types of cancer (19). Some patients experienced a transient increase in pain or nausea and vomiting. However both symptoms subsided and serious side effects were not observed in any of the patients. As reported, we confirmed some abnormal changes in peripheral blood picture. A decrease in the number of white blood cells and platelets was considered to be partly a result of bone marrow suppression due to 89Sr irradiation. Pain was substantially improved after 89Sr therapy in 58% of the patients and there was some alleviation in 12%. The release from pain was accompanied by an improved quality of life for these patients including sleep patterns and morbidity. Some patients were able to resume their former life styles. Most of the improved patients experienced pain relief from days to one week following 89Sr therapy and in half cases, this remained effective for 2 or 3 months. There were even cases in which the pain relief continued over an observation period of time of clinical study.

Adult↗

[Development of a new statistical evaluation method for brain SPECT images].

The purpose of this study was to develop a new statistical evaluation method for Brain SPECT images. First, we made normal brain image databases using 99mTc-ECD and SPECT in 10 normal subjects as described previously. Each SPECT images were globally normalized and anatomically standardized to the standard brain shape using Human Brain Atlas (HBA) of Roland et al. and each subject's X-CT. Then, mean and SD images were calculated voxel by voxel. For the next step, 99mTc-ECD SPECT images of a patient were obtained, and global normalizing and anatomical standardization were performed as the same way. Then, a statistical map was calculated as following voxel by voxel; (P-Mean)/SD x 10 + 50, where P, Mean and SD indicate voxel value of patient, mean and SD images of normal databases, respectively. We found this statistical map was helpful for clinical diagnosis of brain SPECT studies.

Brain↗

Insulin/glucose-, pyruvate- and polyunsaturated fatty acid-responsive region(s) of rat fatty acid synthase gene promoter.

To investigate the regulatory DNA sequences required for polyunsaturated fatty acid (PUFA)-suppression of fatty acid synthase (FAS) gene as well as for insulin and/or carbohydrate-stimulation of this gene, primary hepatocytes were transfected with plasmids containing the 5'-flanking sequence of the rat FAS gene fused to the CAT gene. Sequences from -1604, -88 or -57 to +79 of the FAS gene directed an increase in CAT activity in the hepatocytes when insulin/glucose was added to the medium, in accordance with the responses on the endogenous FAS gene expression. The CAT activities were reduced by the addition of PUFA. Further deletion to -34, however, resulted in loss of the responses. The results suggest that the region from -57 to -34 of the FAS gene may be responsible for regulation due to insulin/glucose and PUFAs. Moreover, the region was also responsible for stimulation due to pyruvate alone.

Animals↗

Changes in extrahepatic biliary motilities with emesis in dogs.

To investigate changes in motility of the extrahepatic biliary system associated with emesis, we measured the volume of the gallbladder and flow resistance through the sphincter of Oddi, as well as antral and duodenal contractilities before and during retching in decerebrate paralyzed dogs. Motilities of the gallbladder, sphincter of Oddi, duodenum and antrum were enhanced with most episodes of fictive retching elicited by stimulation of the central part of the severed dorsal, as well as the ventral trunk of the thoracic vagus nerve. These enhanced motilities persisted until the end of retching. Motilities of the sphincter of Oddi and duodenum were sometimes transiently depressed at the beginning of retching. This depression in the sphincter continued for only 13 +/- 1.0 s, while the gallbladder contraction continued for 65 +/- 3.4 s. Motilities were rarely enhanced by vagal stimulation when retching was not elicited. These changes in motilities were abolished by bilateral vagotomy. The serum gastrin level was increased just after and 10 min after retching only when the ventral vagal trunk remained intact, while the plasma cholecystokinin level was not changed with retching. These results suggest that bile evacuation is interrupted with emesis despite contraction of the gallbladder during retching, since the sphincter of Oddi also contracts simultaneously.

Animals↗

Supplement of nitric oxide attenuates neutrophil-mediated reperfusion injury.

BACKGROUND: Nitric oxide (NO) derived from the endothelial cell has been identified as a constitutive chemical mediator that regulates the function of the endothelial cell in association with neutrophil (PMN) adhesion and activation. However, its role in the pathogenesis of myocardial reperfusion injury is not clear. METHODS AND RESULTS: Fifteen isolated rat hearts were perfused with modified Krebs-Henseleit solution and subjected to 20 minutes of global and normothermic ischemia. Then the hearts were reperfused for 45 minutes with different protocols: the control (C) group was reperfused without PMNs, the P group was reperfused with PMNs, and the N group was reperfused with PMNs and nitroprusside (10(-5) mol/L). The ozone chemiluminescence method was used for direct measurement of NO in the coronary effluent during reperfusion. NO in the coronary effluent in the C group decreased at reperfusion after normoxic perfusion, and this decrease in NO continued for the first 15 minutes of reperfusion. Percentage recovery of left ventricular developed pressure and coronary flow was significantly lower in the P group than that in the N group. Also, the N group had a significantly lesser Luminol-elicited chemiluminescence of the coronary effluent and ratio of PMN adherence to myocardial vasculature compared with the P group. CONCLUSIONS: This study demonstrated directly the decrease in NO production during reperfusion and showed that supplement of NO with NO donor attenuated the injury in which PMNs were involved. The results suggest that NO plays a significant role in reperfusion injury and that supplement of NO during reperfusion appears to be useful to attenuate this injury.

Animals↗

Large scale purification and characterization of TraI endonuclease encoded by sex factor plasmid R100.

The TraI protein encoded by plasmid R100 was purified in a large scale by monitoring the strand- and site-specific nicking activity at the origin of transfer, oriT. The N-terminal amino acid sequence of the purified protein was identical to that deduced from the DNA sequence of an open reading frame encoding TraI. The TraI protein is a DNA helicase which is highly processive and unwinds DNA in the 5' to 3' direction. The Stokes radius and the sedimentation coefficient for the TraI protein in 200 mM NaCl indicate that the protein is a rod-shaped monomer, whose native molecular weight is 186,000. Chemical cross-linking analysis revealed that there exist more dimers of TraI under the low salt conditions, under which both nicking and unwinding reactions catalyzed by TraI are the most efficient, indicating that the TraI protein is functionally active in a dimer form. TraI hardly introduced a nick into the linearized plasmid DNA and only slightly into the relaxed closed circular DNA, indicating that TraI requires superhelical structure of substrate DNA for the nicking reaction. Deletion analysis in the oriT region revealed that a particular region of 54 base pairs containing oriT is required for the nicking reaction.

Amino Acid Sequence↗