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Biomedical subjects

H Fujioka

Publications and source records attributed to H Fujioka.

At least 73 records · Page 4Linked to original sources

Pfsbp1, a Maurer's cleft Plasmodium falciparum protein, is associated with the erythrocyte skeleton.

Antibodies from hyperimmune monkey sera, selected by absorption to Plasmodium falciparum-infected erythrocytes, and elution at acidic pH, allowed us to characterize a novel parasite protein, Pfsbp1 (P. falciparum skeleton binding protein 1). Pfsbp1 is an integral membrane protein of parasite-induced membranous structures associated with the erythrocyte plasma membrane and referred to as Maurer's clefts. The carboxy-terminal domain of Pfsbp1, exposed within the cytoplasm of the host cell, interacts with a 35 kDa erythrocyte skeletal protein and might participate in the binding of the Maurer's clefts to the erythrocyte submembrane skeleton. Antibodies to the carboxy- and amino-terminal domains of Pfsbp1 labelled similar vesicular structures in the cytoplasm of Plasmodium chabaudi and Plasmodium berghei-infected murine erythrocytes, suggesting that the protein is conserved among malaria species, consistent with an important role of Maurer's cleft-like structures in the intraerythrocytic development of malaria parasites.

Amino Acid Sequence↗

The signal sequence and C-terminal hydrophobic domain are required for localization of the sexual stage antigen pgs28 to the surface of P. gallinaceum ookinetes.

The Pgs28 protein is a major surface antigen of the sexual stages of Plasmodium gallinaceum the zygotes and the ookinetes. The protein contains conserved motifs, namely an N-terminal signal sequence, four epidermal growth factor-like repeats and a C-terminal hydrophobic domain that serves as a signal for glycosylphosphatidylinositol (GPI)--anchor modification. In this study, we define the protein motifs required for the surface localization of Pgs28 in ookinetes. using transient transfection combined with immunofluorescence and confocal microscopy. Pgs28 fused to the green fluorescent protein (Pgs28-GFP) is expressed in zygotes, intermediate retort forms and ookinetes. Mutational analyses of Pgs28 coding regions reveal that deletions of the signal sequence and the C-terminal domain result in intracellular retention of the fusion protein. Therefore, the signal sequence and C-terminal domain are required for cell surface localization. Additionally, the Pgs28-GFP fusion proteins are shed from the surface of live ookinetes, suggesting that Pgs28 may be involved in interactions with the cells of the mosquito midgut or during motility.

Animals↗

Absolute stereochemistry of gastric antisecretory compound P371A1 and its congener P371A2 from streptomyces species P371.

Absolute configurations of the gastric antisecretory compound P371A1 (1) and its congener P371A2 (2) from Streptomyces sp. P371 were determined on the basis of identification of the methyl glycosides 9, 10, and 11 obtained by the acid degradation of 1 and 2, as well as application of the modified Mosher method to the P371A2 C-glycoside MTPA esters 7 and 8 and observation of the excitation chiralities in the P371A2 C-glycoside benzoate derivatives 5 and 6.

Aminoglycosides↗

Comparative study of bioartificial liver support and plasma exchange for treatment of pigs with fulminant hepatic failure.

Recently, bioartificial liver (BAL) treatment was reported to provide beneficial effects for patients with fulminant hepatic failure (FHF). Some success in experimental or clinical trials has been reported; however, the evaluation of BAL efficacy remains unclear, especially in comparison with other treatments for FHF. The purpose of this study was to compare the efficacy between BAL and plasma exchange (PE) in experimentally induced FHF in pigs. Pigs undergoing hepatic devascularization (HD) were placed into the following groups: no treatment (control; n = 6), BAL treatment (BAL; n = 5), and plasma exchange (PE; n = 5). Each treatment was initiated 6 h after HD and lasted for 4 h. BAL treatment significantly improved liver functions in FHF pigs. The decrease in cerebral perfusion pressure was also significantly suppressed in the pigs with BAL, and their survival time was prolonged compared with the results in pigs with PE. The effects of BAL outperform those of PE in the treatment of experimental FHF model.

Analysis of Variance↗

Safe and efficient gene transfer into porcine hepatocytes using Sendai virus-cationic liposomes for bioartificial liver support.

Establishment of a bioartificial liver support system using genetically modified hepatocytes is a potential approach to improve the treatment of severe liver failure. We describe the development of an efficient ex vivo method of gene transfer into a large number of porcine hepatocytes using hemagglutinating virus of Japan (HVJ)-liposome. The transfection efficiency of HVJ-liposome into isolated porcine hepatocytes attached to microcarrier beads was evaluated by beta-galactosidase (beta-gal) staining, fluorescence activated cell sorting analysis for beta-gal and luciferase assay, respectively. To examine the function and cellular damage of transduced hepatocytes, we used enzyme-linked immunosorbent assay for porcine albumin synthesis, lidocaine clearance test (P-450 activity), aspartate aminotransferase, and lactic dehydrogenase release assays. The optimal conditions for gene transfer into the beads-attached hepatocytes using HVJ-liposome included 4 microg of deoxyribonucleic acid with 200 microg of lipid/2 x 105 cells and exposure duration of 90 min. Under these conditions, beta-gal and luciferase genes were transduced to 2.5 x 108 isolated porcine hepatocytes following attachment to the beads. Positive beta-gal staining was observed in more than 30% of the beads-attached hepatocytes. The gene transfer activity of HVJ-liposome method determined by luciferase activities was about 100-fold of that of the lipofection method. Transfected porcine hepatocytes remained functional without any significant cell damage. Our results demonstrated that HVJ-liposome mediated gene transfer into microcarrier-attached porcine hepatocytes is an efficient and nontoxic method suitable for a bioartificial liver support sytem.

Animals↗

Treatment of ununited fracture of the hook of hamate by low-intensity pulsed ultrasound: a case report.

A patient presented 4 months after sustaining a fracture of the hook of hamate. X-rays and computed tomography scanning of the carpal tunnel confirmed the presence of an ununited fracture. Low-intensity ultrasound was applied to the fracture site. After 4.5 months of exposure to ultrasound, union was confirmed by both x-rays and computed tomography scanning of the carpal tunnel. (J Hand Surg 2000; 25A:77-79.

Accidents, Traffic↗

Malignant schwannoma of the digital nerve in a child. A case report.

An extremely rare case of malignant schwannoma (malignant peripheral nerve sheath tumor) arising in the digital nerve in the right ring finger of a child is described. The patient was an 8-year-old boy who did not have neurofibromatosis (von Recklinghausen's disease). He noticed a small tender mass on the tip of his right ring finger in 1991. The lesion was excised twice. However, the tumor recurred soon after each surgery. Histologic examination revealed malignant schwannoma. He eventually underwent disarticulation of the ring finger at the metacarpophalangeal joint in 1995. There was no recurrence or distant metastasis at followup in July 1999. Solitary malignant schwannomas can occur in the small peripheral nerves and in the major nerves.

Amputation, Surgical↗

HLA-DRB genotypes in Japanese patients with renal cell carcinoma.

OBJECTIVES: Several clinical features, such as the spontaneous regression of some renal cell carcinoma (RCC) metastases after nephrectomy, suggest immune involvement in tumor destruction. PATIENTS AND METHODS: We investigated the role of genetic variation at the HLA class II loci in RCC by analyzing the HLA-DR antigen and HLA-DRB1, DRB3, DRB4 and DRB5 alleles in 55 patients using the polymerase chain rection. RESULTS: No statistically significant differences were observed in the frequency of the HLA-DR antigen or HLA-DRB3, DRB4, or DRB5 genes between the patients and a healthy control group. On the other hand, the HLA-DRB1*0403 and *1202 alleles were significantly more frequent in the patients than in the controls (p < 0.001 and p < 0.01, respectively). CONCLUSION: RCC might be linked to these two alleles in Japanese patients.

Adult↗

Long-term results of inferior vena cava filters: experiences in a Japanese population.

OBJECTIVE: In this prospective, non-controlled observational study, we evaluated the middle- to long-term results of placement of inferior vena cava (IVC) filter devices in Japanese patients. METHODS AND RESULTS: In 42 Japanese patients with deep vein thrombosis (DVT) or pulmonary thromboembolism (PTE) who underwent percutaneous insertion of IVC filters, follow-up examinations at fixed intervals of 2 years were performed, and the data was evaluated including complications. There were no fatal complications during IVC filter implantation. About 5% of patients with an inserted IVC filter developed symptomatic PTE, another 5% developed asymptomatic PTE. The trapped thrombus was demonstrated in about 22% of the inserted IVC filters. Lower rates of PTE development, occlusion of IVC, and captured thrombus were found in the cases where concurrent use of anticoagulation therapy with filters was used. Trapped thrombi were found in half of IVC filters inserted prophylactically for proximal femoral venous thrombosis. CONCLUSION: These experiences with IVC filters suggest that they are safe and effective for the prevention of PTE in the Japanese population.

Adult↗

Alterations of cartilage and collagen expression during fracture healing in experimental diabetes.

We investigated alterations in the expression of mRNA for type II and type X collagen in fracture callus of experimentally induced diabetic animals compared with controls and performed radiographic, histological, immunocytochemical and biomechanical studies. Experimentally induced diabetic rats exhibited an alteration in the temporal expression of type II and type X collagen mRNA and a decrease in type X mRNA expression as compared to controls. Radiographs showed a more intense periosteal reaction and a more rapid reconstitution of cortices in control versus diabetic animals. Histologically there was a delay in chondrocyte maturation and hypertrophy seen in diabetics. Immunolocalization of type X collagen demonstrated a delay in type X collagen expression around the hypertrophic chondrocytes. Biomechanical analysis showed a decrease in the strength of healing fractures in diabetic animals. Fracture healing in diabetic patients is compromised and may lead to delays in bone union. Though the exact mechanisms are unknown, we present evidence of decreased mechanical strength of the fracture and suggest that associated changes in collagen expression and chondrocyte maturation are mechanisms leading to delayed healing in untreated and poorly controlled diabetes.

Animals↗

[Renal inflammatory pseudotumor after embolization for arteriovenous malformation: a case report].

A 61-year-old man was admitted to our hospital with the chief complaint of asymptomatic macrohematuria. Because he was diagnosed with arteriovenous malformation of the right kidney by angiography, embolization was performed. However, 2 years and 3 months later, bleeding from the right kidney was detected. Computed tomography (CT) revealed a low density area (1.8 cm) in the right kidney protruding to the renal pelvic adjacent to the old embolized lesion. Since we could not make a conclusive diagnosis as malignant disease by ureteroscopy and angiography, we have decided to follow the case carefully. Nine months later, macroscopic hematuria worsened, and the low density area by CT in the right kidney expanded. Therefore, we finally decided to perform right total nephroureterectomy. The tumor was histologically diagnosed as renal inflammatory pseudotumor. This is the 14th case reported in Japan. We here report the renal inflammatory pseudotumor with a review of the Japanese literature.

Arteriovenous Malformations↗

[A case of urinary stone in ureterocele extracted transurethrally after ESWL].

A 66-year-old man was referred to our hospital with chief complaints of difficulty in urination and terminal micturition pain. Ureteroceles were identified bilaterally, and a ureteral stone (19 x 12 mm) existed in the right ureterocele. After crushing the stone by extra corporeal shock wave lithotripsy (ESWL), we removed the stone transurethrally with a small incision in the right ureterocele. The vesicoureteral reflux (VUR) was not detected postoperatively. Now, we recommend the combination of ESWL and a small transurethral incision of the urelerocele for the treatment of ureteral stones in a ureterocele in order to prevent postoperative VUR.

Aged↗

[Retrieval and cryopreservation of testicular sperm].

We reviewed 44 cases of non-obstructive azoospermia treated by testicular sperm extraction and intracytoplasmic sperm injection (ICSI) from July, 1997 to September 1999 at our institutes. Testicular sperm were retrieved from 32 patients (72.7%). ICSI was performed on 29 patients and the partners of 15 patients (46.9%) became pregnant. Out of 10 patients with histology of Sertoli-cell-only, we could retrieve sperm from 3 patients (30%). Testicular volume, Johnsen's score count (JSC), and FSH were significant parameters to predict the recovery of testicular sperm from the patients, but if only the patients with JSC less than 8, are analyzed, none of them was significant parameter. Chromosomal abnormality was not a significant parameter. The partner's age, motility of recovered sperm and testicular volume correlated with the fertilization rate. Chromosomal abnormality or the usage of cryopreserved sperm was not a significant parameter to predict fertilization.

Adult↗

[A case of ammonium urate urinary stones with anorexia nervosa].

A 27-year-old woman had been suffering from bulimia and habitual vomiting for about 7 years and was incidentally found to have right renal stones by computed tomography. She was referred to our hospital for the treatment of these caluculi. On admission, she presented with hypokalemia, hypochloremia and metabolic alkalosis and was diagnosed with anorexia nervosa. Following successful removal by percutaneous nephrolithotripsy and extracorporeal shockwave lithotripsy the stones were found to consist of pure ammonium urate. Since the urine of an anorexia nervosa patient tends to be rich in uric acid and ammonium, anorexia nervosa seems to be associated with ammonium urate urinary stones.

Adult↗

Inhibition by adrenomedullin of amine release from adrenergic nerves in dog mesenteric arteries.

Adrenomedullin and calcitonin gene-related peptide (CGRP) inhibited the pressor response to transmural electrical stimulation in perfused isolated canine mesenteric arteries. The response was abolished by treatment with either prazosin or tetrodotoxin. Adrenomedullin-(22-52), an adrenomedullin receptor antagonist, reduced the inhibitory effect of adrenomedullin (10(-10) to 10(-8) mol/l), but did not alter the action of CGRP. CGRP-(8-37), a CGRP(1) receptor antagonist, did not affect the inhibition induced by adrenomedullin, but reversed the CGRP-induced inhibition. In helical strips of the arteries, adrenomedullin (up to 10(-8) mol/l) did not influence the contraction induced by noradrenaline, whereas CGRP attenuated the response. Adrenomedullin decreased the release of noradrenaline from adrenergic nerves elicited by transmural electrical stimulation, but CGRP had no effect. Adrenomedullin-(22-52) reversed the decrease in noradrenaline release induced by adrenomedullin. The adrenomedullin-induced relaxation of vascular strips precontracted with prostaglandin F(2alpha) was suppressed by CGRP-(8-37) but was unaffected by adrenomedullin-(22-52). These findings suggest that adrenomedullin impairs noradrenaline release from adrenergic nerves by acting on adrenomedullin receptors located in the nerve terminals, whereas arterial relaxation caused by adrenomedullin and CGRP is due to activation of CGRP(1) receptors in vascular smooth muscle.

Adrenergic Fibers↗