Biomedical subjects

Masahiko Fujii

Publications and source records attributed to Masahiko Fujii.

At least 19 recordsLinked to original sources

PubMed2006

Kinetic analysis of the cervical spinal cord in patients after spinous process-splitting laminoplasty using a kinematic magnetic resonance imaging technique.

STUDY DESIGN: An in vivo flexion-extension magnetic resonance imaging study. OBJECTIVE: To evaluate the kinetic changes of the cervical spinal cord after laminoplasty in patients with cervical myelopathy. SUMMARY OF BACKGROUND DATA: Laminoplasty for cervical myelopathy increases the space occupied by the spinal cord, leading to a decompressive effect on the cord. However, there are few reports on kinetic changes of the spinal cord following this surgical procedure, by which it may contribute to an improvement of clinical symptoms. METHODS: Patients who underwent spinous process-splitting laminoplasty (n = 40) and control group (n = 20) were enrolled in the study. Cervical spines of the subjects were examined from maximum extension to maximum flexion using a magnetic resonance imaging scanner. Sagittal T1-weighted images were obtained at 12 different angle positions. Images were analyzed with respect to the distance and alignment disparity between the dorsal edge of the vertebral column and the center of the cord at each disc level using National Institutes of Health Image software. RESULTS: Spinal cords of patients after laminoplasty were dorsally shifted in the enlarged spinal canal at neutral, extension, and flexion positions. Alignment changes of the cord during flexion-extension movements of the cervical spine were dissociated from those of the vertebral column because of smaller changes in the cord alignment. CONCLUSIONS: Spinous process-splitting laminoplasty increases the degree of freedom of the spinal cord.

Aged↗

PubMed2006

Anticoagulant-induced pseudothrombocytopenia occurring after transcatheter arterial embolization for hepatocellular carcinoma.

Pseudothrombocytopenia (PTCP) is the in vitro phenomenon of anticoagulant-activated platelet agglutination that results in spuriously low platelet counts. We report the case of a 65-year-old man with EDTA- and sodium citrate-dependent PTCP occurring after transcatheter arterial embolization (TAE) for hepatocellular carcinoma (HCC) due to hepatitis C cirrhosis. Invasion of the portal and hepatic veins by HCC formed severe trans-tumoral arterio-venous shunts that were effectively treated by TAE. Two days after the therapy, PTCP was seen on blood count and continued for 4 months. The patient received unnecessary treatment for disseminated intravascular coagulation (DIC) until the diagnosis of PTCP was established. PTCP is a rare complication but should be considered after TAE for HCC; lack of recognition may lead the physician to misdiagnosis and patient mismanagement.

Aged↗

PubMed2006

Combination therapy of human pancreatic cancer implanted in nude mice by oral fluoropyrimidine anticancer agent (S-1) with interferon-alpha.

PURPOSE: We evaluated the antitumor and antiangiogenic activities of human natural interferon-alpha (IFN-alpha) alone or in combination with S-1 against human pancreatic cancer cells. METHODS: Three days after the subcutaneous (s.c.) implantation of tumor cells, mice (n = 12) were received s.c. injection with IFN-alpha alone (10,000 U six times a week), oral administration with S-1 alone (8 mg/kg six times a week), or both with IFN-alpha and S-1 (8, 10, 12 mg/kg six times a week). RESULTS: Administration of IFN-alpha in combination with S-1 significantly decreased progressive growth and angiogenesis of human pancreatic cancer cells. The combination therapy produced more significant inhibition in expression of the representative proangiogenic molecules, vascular endothelial growth factor and basic fibroblast growth factor than individual treatment either IFN-alpha or S-1 alone did. These treatments also decreased the staining of proliferating cell nuclear antigen, induced apoptosis and decreased microvessel density. In order to better understand the precise molecular mechanisms by which IFN-alpha and S-1 exert its effects, we have utilized cDNA microarray including 124 known genes to determine the gene expression profile altered by IFN-alpha and S-1 treatment. We found a total of seven genes which showed a twofold change after IFN-alpha and S-1 treatment in addition to VEGF, bFGF, CD31, MMP-2, MMP-7 and MMP-9. Among these genes, we found down-regulation of six genes and up-regulation of one gene, which are related to angiogenesis, tumor cell invasion and metastasis. CONCLUSIONS: These data suggest that administration of IFN-alpha in combination with S-1 may provide a novel and effective approach to the treatment of human pancreatic cancer.

Angiogenesis Inhibitors↗

PubMed2006

Focal liver lesions: breathhold gradient- and spin-echo T2-weighted imaging for detection and characterization.

PURPOSE: To evaluate breathhold gradient- and spin-echo (GRASE) T2-weighted imaging for the detection and characterization of focal liver lesions. MATERIALS AND METHODS: Two GRASE sequences with different echo times (75 and 90 msec, GRASE75 and GRASE90) were compared with respiratory-triggered fast spin-echo (SE) and breathhold fast SE in 64 patients with 103 malignant and 51 benign lesions. Compared with respiratory-triggered and breathhold fast SE, GRASE reduced scan time by 77% to 82% and 21% to 27%, respectively. Two independent readers evaluated image quality and reviewed 504 liver segments on a segment-by-segment basis. Observer performance was evaluated with receiver operating characteristic (ROC) curve analysis. The signal-to-noise ratio (SNR) of liver and spleen, and lesion-to-liver contrast-to-noise ratio (CNR) were also measured. RESULTS: The overall quality of the GRASE images was higher than that of the respiratory-triggered and breathhold fast SE images, although signal inhomogeneities were more frequently observed with GRASE. No significant difference in the values of the area under the ROC curve (Az) for malignant lesion detection was found. The mean SNR and CNR were highest for respiratory-triggered fast SE. CONCLUSION: T2-weighted breathhold GRASE has the potential to provide faster liver imaging.

Adult↗

PubMed2006

Gradient- and spin-echo T2-weighted imaging for SPIO-enhanced detection and characterization of focal liver lesions.

PURPOSE: To evaluate superparamagnetic iron oxide (SPIO)-enhanced breathhold T2-weighted GRASE imaging in detection and characterization of focal liver lesions. MATERIALS AND METHODS: In 30 patients (including 20 with cirrhosis) with 39 malignant and 25 benign lesions, gradient- and spin-echo (GRASE) images with two echo times (75 and 90 msec; GRASE75 and GRASE90) were obtained prior to and following administration of SPIO, and compared with respiratory-triggered and breathhold fast spin-echo (RT-FSE and BH-FSE) images. Two readers evaluated image quality and reviewed 240 liver segments for sensitivity and specificity. Signal-to-noise ratio (SNR), and its reduction in liver and spleen after administration of SPIO, and lesion-to-liver contrast-to-noise ratio (CNR) were measured. RESULTS: Compared with RT-FSE and BH-FSE, GRASE reduced scan time by 77% to 82% and 21% to 27%, respectively. The image qualities with BH-FSE and GRASE75 were higher than with BH-FSE and GRASE90. BH-FSE showed higher specificity than RT-FSE and GRASE90, but otherwise there were no significant differences between pulse sequences for sensitivity or specificity. The mean SNR and CNR of the lesions with RT-FSE were significantly higher than with the other methods. SPIO-induced signal reduction of liver SNR was smallest with BH-FSE. CONCLUSION: GRASE is faster and more sensitive to SPIO than FSE, but its sensitivity and specificity were slightly inferior to those of BH-FSE. Image quality is a current limitation.

Adult↗

PubMed2006

High-resolution MRI using a microscopy coil for the diagnosis of recurrent lateral patellar dislocation.

PURPOSE: Magnetic resonance imaging (MRI) has been commonly used for the preoperative evaluation of recurrent lateral patellar dislocation (RLPD). The purpose of this study was to determine the usefulness of high-resolution MRI (HR-MRI) with a microscopy coil for diagnosing RLPD. MATERIALS AND METHODS: The study group consisted of 15 patients with clinically diagnosed RLPD and 10 normal volunteers. All studies were performed on a 1.5-T MR system. First, conventional MRIs of the whole knee joint were obtained using the knee coil. Then HR-MRI scans using a microscopy coil in the medial aspect of the patella were obtained at the level of the superior pole of the patella, targeting the medial patellofemoral ligament (MPFL). The acquired HR-MRIs with RLPD were reviewed concerning the MPFL injury and the patellar injury. RESULTS: The MPFL was distinguished as a separate ligament, and the layer structure of the patellar cartilage was visualized clearly in all volunteers. The MPFL injury was visualized in 12 cases (87%); it included discontinuity, thickening, and loosening. The patellar injury was visualized in 11 cases (73%), which included dissecans of the medial margin and cartilage injuries. CONCLUSION: HR-MRI with a microscopy coil provides precise information of the MPFL and patellar cartilage injury for the diagnosis of RLPD.

Adolescent↗

PubMed2006

Clinical roles of increased populations of Foxp3+CD4+ T cells in peripheral blood from advanced pancreatic cancer patients.

OBJECTIVES: Further metastasis should be avoided in pancreatic cancer (PC) patients for effective surgical treatment. Regulatory T cells (Foxp3CD4 T cells including CD4CD25 T cells and CD4CD25 T cells) play important roles in tumor immunity. This study aimed to investigate whether regulatory T cells participate in metastasis. METHODS: Peripheral blood was withdrawn from PC patients, as well as healthy volunteer donors as controls. The peripheral blood mononuclear cells (PBMCs) were subjected to FACScan analysis after labeling with anti-CD4, anti-CD25, and anti-Foxp3 antibodies. Tumor markers, including DUPAN2 and CA19-9, surface markers, such as the CD4/CD8 ratio, and the CD57 cell population were assessed. Clinical stages were classified according to the TNM classification. RESULTS: The Foxp3CD4 T-cell population among the PBMCs was significantly increased in PC patients (8.10% +/- 4.65%) compared with healthy donors (2.47 +/- 0.78%) (P < 0.001). No significant relationships existed for the tumor markers, CD4/CD8 ratio, and CD57 cells. However, a significant correlation was found between Foxp3CD4 T cells among the PBMCs and the TNM stage (P < 0.05). CONCLUSIONS: Foxp3CD4 T cells are good markers for metastasis detection in PC patients and more accurate than other conventional tumor markers, especially at advanced stages of the disease.

Aged↗

PubMed2006

Rapid-growing solitary necrotic nodule of the liver.

The solitary necrotic nodule of the liver is an uncommon nonmalignant lesion with an uncertain etiology. The lesion was defined as a nodule with a completely necrotic core and fibrous capsule etc. and without a consistency of viable cells. The characteristic features of this benign lesion on the imaging modalities are similar to the metastatic tumor. In this paper we discuss the case of a rapid-growing solitary necrotic nodule of the liver occurring in a patient with chronic renal failure on hemodialysis. The lesion located on the left median lobe of the liver had rapidly enlarged in diameter in the last seven months. Despite some examinations by imaging modalities to confirm the preoperative diagnosis, we were unable to visually confirm. Several histological examinations using a needle biopsy specimen were performed, but the diagnosis was all necrotic tissue. However, we recommended an extended left hepatic lobectomy for this rapid-growing lesion since cholangiocarcinoma with necrosis could be hardly differentiated. Permanent histology revealed that the lesion was solitary necrotic nodule. We consider that permanent histology of the entire lesion is possibly the only accurate method of diagnosis. Since the solitary necrotic nodule does not indicate malignancy, hepatic resection should be performed.

Bile Duct Neoplasms↗

PubMed2006

Conventional MRI capabilities in the diagnosis of prostate cancer in the transition zone.

OBJECTIVES: Our objectives were to evaluate the diagnostic capabilities of conventional MRI for the accurate detection of prostate cancer within the transition zone and to compare the results with histopathologic examination results. MATERIALS AND METHODS: One hundred sixteen prostate specimens with prostate cancer were consecutively obtained. Axial, sagittal, and coronal T2- and T1-weighted MR images with gadopentetate dimeglumine were independently reviewed by two radiologists. The diagnostic base criteria of the MR images were determined for detecting transition zone cancer as follows: lesions with A, uniform low intensity on T2-weighted images; B, homogeneous gadolinium enhancement; and C, irregular margins both on gadolinium-enhanced and T2-weighted images. Wilcoxon's rank sum and chi-square tests and receiver operating characteristic curves were used. Differences of less than 0.05 were considered significant. RESULTS: Eighty-six lesions in the transition zone were analyzed. Histopathologic analysis showed 53 cancers and 33 benign lesions. The diagnostic sensitivity, specificity, and accuracy for cancer were 50%, 51%, and 51%, respectively with criteria A; 68%, 75%, and 71% with criteria B; and 60%, 72%, and 65% with criteria C. When base criteria were combined into criteria A-B, A-C, and B-C and then further divided into three subgroups, accuracy was found to be highest when the lesion satisfied any two criteria from A, B, and C than those of base criteria, combination criteria, and the other two subgroups. CONCLUSION: The addition of gadolinium-enhanced MRI to T2-weighted imaging provides better accuracy for detecting cancerous transition zone lesions than the use of T2-weighted imaging alone.

Aged↗

PubMed2006

ADC measurement of abdominal organs and lesions using parallel imaging technique.

OBJECTIVE: The purpose of our study was to assess the reliability and usefulness of parallel imaging for apparent diffusion coefficient (ADC) measurement of abdominal organs and lesions. MATERIALS AND METHODS: Single-shot spin-echo echo-planar diffusion-weighted MRI (TE = 66, b = 0, 600 s/mm2) was performed in phantom and clinical studies. The b value was set to minimize the effects of perfusion in tissue and to maintain signal-to-noise ratio. Bottle phantoms were scanned with and without parallel imaging and with various parallel imaging factors and at various positions to evaluate the effects of parallel imaging on ADCs. In 200 consecutive clinical patients (122 men and 78 women: mean age, 61.9 years), ADCs were calculated for liver (four segments), spleen, pancreas (head, body, tail), gallbladder, renal parenchyma, and back muscle, and then compared to evaluate the reliability of clinical ADC measurements with parallel imaging. ADCs were also calculated for diffuse diseases and focal lesions (94 malignant and 93 benign) of abdominal organs to evaluate the clinical usefulness of ADC. RESULTS: Location-dependent changes in water ADCs were minimal with parallel imaging factors first of 3, then of 4, and were small except for measurements at the image periphery. Acetone ADCs were saturated at 4.00 x 10(-3) mm2/s. Degraded image quality prevented ADC measurement of the left hepatic lobe and pancreas in 7-18 patients. There was no significant difference among ADCs of four liver segments (1.50 +/- 0.24 [SD] x 10(-3) mm2/s - 1.56 +/- 0.31 x 10(-3) mm2/s) and between ADCs of the right and left kidneys (2.65 +/- 0.30 x 10(-3) mm2/s, 2.59 +/- 0.33 x 10(-3) mm2/s). ADC of the pancreas tail (1.65 +/- 0.37 x 10(-3) mm2/s) was significantly lower than those of the head (1.81 +/- 0.40 x 10(-3) mm2/s) and body (1.81 +/- 0.41 x 10(-3) mm2/s) (p < 0.005). Renal ADCs were significantly lower in patients with renal failure (right: 2.15 +/- 0.30 x 10(-3) mm2/s; left: 2.11 +/- 0.25 x 10(-3) mm2/s) than in those without disease (right: 2.67 +/- 0.29 x 10(-3) mm2/s; left: 2.60 +/- 0.32 x 10(-3) mm2/s) (p < 0.005). ADC of pancreatic cancer was significantly higher than that of healthy pancreas (p < 0.05). ADC of renal angiomyolipoma was significantly lower than those of renal cell carcinoma and healthy renal parenchyma (p < 0.0005). CONCLUSION: Clinical ADC measurements of abdominal organs and lesions using parallel imaging appear to be reliable and useful, and the effect of parallel imaging on calculated values is considered to be minimal.

Adult↗

PubMed2006

[Effects of magnetic resonance imaging on neutrophil functions].

We evaluated the effects of magnetic resonance (MR) imaging on human neutrophil functions. In addition of the counting of leukocyte and neutrophil number, expression levels of adhesion molecules on neutrophil surface such as CD11b and L-selectin, and reactive oxygen species (ROS) production were determined by means of flowcytometry. Complete blood count did not show any difference between before and after MR imaging in five normal healthy volunteers. The levels of cell surface adhesion molecules were not altered in both in vivo MR imaging (n=5) and in vitro MR exposure experiments (n=13). Moreover, the levels of ROS production were also not affected by in vivo MR imaging. On the other hand, neutrophils exposed to MR in vitro exhibited significant increase in ROS production after stimulation with fMLP combined with lipopolysaccharide, although no increase was observed with PMA stimulation. Actually, there have been no reports describing the complication relating to hyper-neutrophil function as far as we could search, but it might be necessary to evaluate the biological effects of MR imaging especially under the pathologic circumstances that induce neutrophil activation.

Adult↗

PubMed2005

Usefulness of MRI for diagnosis of painful snapping elbow.

Painful snapping of the elbows is rare. We report on a 12-year-old boy with a painful snap in both elbows. High-resolution magnetic resonance imaging of the elbow using microscopy coils detected a synovial fold interposed in each humeroradial joint and was very helpful in establishing the cause of symptoms. Resection of the synovial folds was performed with subsequent relief of symptoms.

Arthralgia↗

PubMed2005

Thin-section multiplanar reformats from multidetector-row CT data: utility for assessment of regional tumor extent in non-small cell lung cancer.

PURPOSE: To determine the clinical utility of thin-section multiplanar reformats (MPRs) from multidetector-row CT (MDCT) data sets for assessing the extent of regional tumors in non-small cell lung cancer (NSCLC) patients. MATERIALS AND METHODS: Sixty consecutive NSCLC patients, who were considered candidates for surgical treatment, underwent contrast-enhanced MDCT examinations, surgical resection and pathological examinations. All MDCT examinations were performed with a 4-detector row computed tomography (CT). From each raw CT data set, 5mm section thickness CT images (routine CT), 1.25 mm section thickness CT images (thin-section CT) and 1.25 mm section thickness sagittal (thin-section sagittal MPR) and coronal images (thin-section coronal MPR) were reconstructed. A 4-point visual score was used to assess mediastinal, interlobar and chest wall invasions on each image set. For assessment of utility in routine clinical practice, mean reading times for each image set were compared by means of Fisher's protected least significant difference (PLSD) test. A receiver operator characteristic (ROC) analysis was performed to determine the diagnostic capability of each of the image data sets. Finally, sensitivity, specificity and accuracy of the reconstructed images were compared by McNemar test. RESULTS: Mean reading times for thin-section sagittal and coronal MPRs were significantly shorter than those for routine CT and thin-section CT (p<0.05). Areas under the curve (Azs) showing interlobar invasion on thin-section sagittal and coronal MPRs were significantly larger than that on routine CT (p=0.03), and the Az on thin-section sagittal MPR was also significantly larger than that on routine CT (p=0.02). Accuracy of chest wall invasion by thin-section sagittal MPR was significantly higher than that by routine CT (p=0.04). CONCLUSION: Thin-section multiplanar reformats from multidetector-row CT data sets are useful for assessing the extent of regional tumors in non-small cell lung cancer patients.

Adult↗

PubMed2005

Inverse correlation between serum adiponectin concentration and hepatic lipid content in Japanese with type 2 diabetes.

Adiponectin is an adipose tissue-specific protein and plays an important role in insulin sensitivity. On the other hand, intramyocellular lipid content and hepatic lipid content (HLC) are related to insulin resistance in humans. In the present study, the possible relations between the serum concentration of adiponectin and intracellular triglyceride content in skeletal muscle and in the liver were investigated in individuals with type 2 diabetes mellitus. Fifty Japanese sedentary subjects (34 men, 16 women) with type 2 diabetes who had neither been treated with insulin nor with thiazolidinediones were enrolled in the study. Insulin sensitivity in vivo was evaluated by measurement of the glucose infusion rate during a hyperinsulinemic-euglycemic clamp and of the homeostasis model of assessment-insulin resistance index. The intracellular triglyceride content in skeletal muscle and the liver was determined by nuclear magnetic resonance. The serum adiponectin concentration was inversely correlated with both HLC ( r = -0.39, P < .01) and the homeostasis model of assessment-insulin resistance index ( r = -0.32, P < .05), but it was not significantly related to either intramyocellular lipid content or glucose infusion rate during the hyperinsulinemic-euglycemic clamp in individuals with type 2 diabetes. These results suggest that adiponectin might play an important role in the regulation of HLC and basal insulin sensitivity in individuals with type 2 diabetes.

Adiponectin↗

PubMed2005

Balloon occluded retrograde transvenous obliteration and percutaneous transhepatic obliteration for ruptured duodenal varices after operation for rectal cancer with multiple liver metastasis: report of a case.

We report a patient with duodenal varices oozing blood who had undergone low anterior resection of the rectum and resection of the liver tumor because of multiple liver metastasis from rectal cancer 80 months previously. Although endoscopic variceal ligation (EVL) was carried out for the ruptured duodenal varices, their bleeding persisted and hepatic encephalopathy also appeared. Finally, balloon occluded retrograde transvenous obliteration (BRTO) with percutaneous transhepatic obliteration (PTO) was carried out for the duodenal varices. Percutaneous transhepatic portography revealed detailed hemodynamics. Following PTO, the duodenal varices were stagnated by BRTO, and no complications were recognized. No re-bleeding episode has been observed since the treatment. In addition, the hepatic encephalopathy was also improved.

Adult↗

PubMed2005

Multiple hepatic angiomyolipomas with a solitary omental angiomyolipoma.

Angiomyolipoma (AML) is a rare benign tumor that occurs most commonly in the kidney. Lesions in the liver are usually solitary and multiple AMLs of the liver are extremelyrare. Furthermore, extra renal or hepatic AML are rarely found. We report an unusual case of a 34-year-old man with a solitary omental AML and multiple hepatic AMLs. At the age of 23, the patient underwent right nephrectomy and enucleation of a left renal tumor because of bilateral AMLs. At the age of 34, more than 6 lesions in the liver and an enlarged solitary omental AML were discovered. The omental tumor, 50 x 40mm, 49g, was extirpated; it was well-defined and encapsulated a soft elastic mass. Histologically it was an epithelioid AML and positive for the melanogenesis-related marker HMB-45, the same as the earlier right renal tumor. We describe the first case of a solitary omental AML, which had metastasized, and with more than 6 hepatic AMLs.

Adult↗

PubMed2005

Living-donor liver transplantation: present status and future perspective.

About 15 years have passed since the first liver transplant from a living donor (living donor liver transplantation: LDLT), and the status of the procedure has since been established as a standard cure for end-stage liver disease in Japan where liver transplantation (LTx) from deceased donors has not yet been accepted. However, the following problems are surfacing with the increase in the number of LDLTs between adults: graft size mismatching, an ABO blood-type incompatible transplantation, the expansion of LDLT indication to hepatocellular carcinoma (HCC), the relapse of hepatitis C after LDLT, marginal donors, and the freedom from immunosuppressive treatment. In this article we outline the present conditions of these problems and the future view of the LDLT.

ABO Blood-Group System↗

PubMed2005

A randomized, observer-blind, controlled trial of the traditional Chinese medicine Yi-Gan San for improvement of behavioral and psychological symptoms and activities of daily living in dementia patients.

OBJECTIVE: This randomized, observer-blind, controlled trial examined the efficacy and safety of the traditional Chinese herbal medicine Yi-Gan San (YGS, Yokukan-San in Japanese) in the improvement of behavioral and psychological symptoms of dementia (BPSD) and activities of daily living (ADL). METHOD: Fifty-two patients with mild-to-severe dementia (24 men and 28 women, mean +/- SD age = 80.3 +/- 9.0 years) according to DSM-IV criteria were investigated. Participants were randomly assigned to the YGS group (N = 27) or control (drug-free) group (N = 25) and treated for 4 weeks. The Neuropsychiatric Inventory (NPI) for the assessment of BPSD, the Mini-Mental State Examination (MMSE) for cognitive function, and the Barthel Index for ADL were administered at baseline and the end of the treatment. The frequency of extrapyramidal symptoms (EPS) and other adverse events was recorded. If patients showed insufficient response to treatment after 1 week, tiapride hydrochloride, a dopamine D(1) selective neuroleptic, was added to the regimen. Data were collected from January 2004 to March 2004. RESULTS: All participants in both groups completed the trial. In the control group, 11 patients required treatment with tiapride hydrochloride. Significant improvements in mean +/- SD NPI (from 37.9 +/- 16.1 to 19.5 +/- 15.6) and Barthel Index (from 56.4 +/- 34.2 to 62.9 +/- 35.2) scores were observed in the YGS group, but not in the control group. MMSE results were unchanged in both groups. EPS were not observed in either group, but dizziness and impaired postural sway were observed in 6 patients treated with tiapride hydrochloride. CONCLUSION: Yi-Gan San improves BPSD and ADL. Follow-up studies using a double-blinded, placebo-controlled design are recommended.

Activities of Daily Living↗