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H Fujioka

Publications and source records attributed to H Fujioka.

At least 19 recordsLinked to original sources
PubMed1997

Molecular characterization and ultrastructural localization of Plasmodium falciparum Hsp 60.

Heat shock proteins (Hsp) are a group of highly conserved proteins which are widely represented phylogenetically. Genes for members of the Hsp 70, 90 and 60 families have been cloned from the human malaria parasite Plasmodium falciparum. In this study, we have cloned and expressed the P. falciparum Hsp 60 (PfHsp60) in E. coli. The sequence analysis identified a previously unknown intron of 257 bp beginning after the nucleotide 142 in the coding sequence. Antisera raised against the recombinant PfHsp60 was employed in immunoprecipitation studies with biosynthetically labeled parasite extracts to investigate regulation of expression of PfHsp60 at various temperatures. In contrast to the three to four fold accumulation of PfHsp60 transcripts in heat shocked parasites (37-40 degrees C), the expression of PfHsp60 was not induced in the blood stages of P. falciparum. On the other hand, the effect of heat induction on PfHsp70 was seen both at the level of specific mRNA and protein. In these studies we also observed co-immunoprecipitation of a number of other cellular proteins suggesting possible interaction with PfHsp60. Immunofluorescence analysis indicated the presence of PfHsp60 in the cytoplasm of all the various stages of the parasite. In addition, immunoelectron microscopic analysis distinctly localized PfHsp60 in the mitochondrion of P. falciparum. This study suggests that different mechanisms are involved in the regulation of expression of various members of the heat shock proteins in the parasite.

Animals↗
PubMed1997

Primary lymphoma of the heart, diagnosed antemortem.

Primary cardiac lymphomas diagnosed antemortem are extremely rare. We present a case of primary cardiac lymphoma initially diagnosed antemortem by cytologic examination of pericardial effusion fluid. Echocardiography suggested the presence of a tumor localized at the right ventricular free wall. The cytologic examination of pericardial effusion was effective in establishing the correct antemortem diagnosis.

Aged↗
PubMed1997

[Long-term follow-up study of bone mineral density in a patient with adult idiopathic Fanconi syndrome].

A 64-year-old woman complaining of severe lumbar pain was admitted to our hospital because of the finding of pre-existing mitral valve regurgitation on examination. Laboratory data revealed the proximal type of renal tubular acidosis, renal glucosuria, phosphaturia, generalized aminoaciduria and low-molecular-weight proteinuria. She did not have any cause of these tubular dysfunctions, and was diagnosed as adult idiopathic Fanconi syndrome. Dual energy X-ray absorptiometry (DEXA) revealed a reduction of bone mineral density in the lumbar spine to about 65% of the age-and gender-matched control value. Alkali agents (sodium citrate and potassium citrate), calcium lactate and 1 alpha-hydroxyvitamin D3 were administered. Bone mineral density estimated with DEXA improved with a reduction of serum alkali phosphate and disappearance of lumbar pain, and was restored to 82% of the age-and gender-matched control value after about 30 months of treatment. DEXA is useful for the long-term follow-up study of bone mineral density in a patient with Fanconi syndrome.

Absorptiometry, Photon↗
PubMed1997

[Renal cell carcinoma in a horseshoe kidney: a case report].

A 69-year-old man presented for further examination for left renal mass. Computed tomography and magnetic resonance imaging revealed a heterogenous mass on the left side of a horseshoe kidney accompanied with renal vein thrombus. Aortography showed a hypervascular mass in the left kidney and aberrant arteries to the isthmus originating from the aorta. A left nephrectomy with the division of the isthmus was performed through an abdominal transperitoneal approach. Histological evaluation revealed grade 2, stage T3b, renal cell carcinoma. The patient was free of tumor, but died of intracerebral hemorrhage 5 months after the operation.

Aged↗
PubMed1997

[Compton-scatter correction using the triple energy window (TEW) method in conventional single photon emission computed tomography without TEW acquisition hardware].

We devised a method which allowed the triple energy window (TEW) method to be applied for Compton-scatter correction in conventional single photon emission computed tomography (SPECT) systems without any hardware for TEW acquisition. In this method, the data within two subwindows located at both sides of the main window were acquired together. The effectiveness of this method was investigated by phantom experiments. The integral and differential uniformities measured using a flood phantom filled with 123I were minimized when the energy width of subwindows was 5 keV (5.8% and 4.2%, respectively). When this method was applied to a brain phantom filled with 123I in which the relative activities in white and gray matter were assigned as 1: 4.3, the ratio of SPECT values between them was more accurate (1:4.26) than that obtained without this method (1:208). This method appears to be useful for Compton-scatter correction in SPECT, because it can be applied to conventional SPECT systems without any hardware for TEW acquisition and is available for routine clinical use for its simplicity.

Brain↗
PubMed1997

[Renal cell carcinoma associated with renal artery aneurysm].

We report the 5th case of renal cell carcinoma associated with renal artery aneurysm in the Japanese literature. A 57-year-old woman was admitted to our hospital for further examination of a right renal mass. Computerized tomography and magnetic resonance imaging revealed a 6 x 5 cm tumor at the upper pole of the right kidney and an aneurysm of the right renal artery. An angiography showed duplicated renal arteries and a saccular aneurysm 2.1 x 2.5 cm occurring at the first bifurcation of one renal artery. A transperitoneal radical nephrectomy was performed.

Aneurysm↗
PubMed1996

Stage-specific processing of Pfs230, a Plasmodium falciparum transmission-blocking vaccine candidate.

During Plasmodium falciparum gametocytogenesis, Pfs230, a malaria transmission-blocking vaccine candidate, is expressed as a 360 kDa protein localized to the parasitophorous vacuole/parasite plasma membrane. When gametocytes emerge from red blood cells, as they do when taken up in a blood meal by a mosquito, Pfs230 is processed from a 360 kDa form to a 310 kDa form the latter of which is exposed on the exterior surface of gametes. The 50 kDa portion of Pfs230, removed from the amino-terminus of the 360 kDa form, contains 25 contiguous glutamates and an EEVG16 repeat. Analogous to other P. falciparum proteins, the repeat region appears to be immunodominant. As the gamete emerges from the red blood cell and is exposed to the antibodies in the blood meal, cleavage of the immunodominant region of Pfs230 may contribute to an immune evasion strategy by the parasite.

Amino Acid Sequence↗
PubMed1996

Somatosensory evoked potentials recorded from the posterior pharynx to stimulation of the median nerve and cauda equina.

Somatosensory evoked potentials (ppSEPs) in response to stimulation of the median nerve at the wrist and the cauda equina at the epidural space (the L4 level) were recorded from the posterior wall of the pharynx in 15 patients who underwent spinal surgery under general anesthesia, using disc electrodes attached to the endotracheal tube, and compared with segmental spinal cord potentials (seg-SCPs) that were recorded simultaneously from the posterior epidural space (PES). ppSEPs consisted of the initially positive spike (P9) followed by slow positive (P13) and negative (N22) waves. The P13 and N22 of ppSEPs had phase reversal relationship with the P2 and N2 recorded from the PES, respectively. The peak latencies of P9 (9.40 +/- 0.7 ms) (mean +/- SD), P13 (13.1 +/- 0.9 ms), and N22 (22.0 +/- 2.1 ms) of ppSEPs coincided with those of P1, N1 and P2 of seg-SCPs, respectively, ppSEPs were recorded more clearly with a reference electrode on the dorsal surface of the neck than with the reference electrode at the earlobe or back of the hand. The threshold and maximal stimulus intensities were also similar between the ppSEPs and seg-SCPs. Thus, the P9, P13, and N22 components of ppSEPs were thought to have the same origin as the P1, N1 and P2 of seg-SCPs, respectively. Therefore, the P9, P13 and N22 of ppSEPs may reflect incoming volleys through the root, synchronized activities of the interneurons and primary afferent depolarizations (PAD), respectively. ppSEPs in response to cauda equina stimulation showed that the latencies of the two initial components (4.6 +/- 0.4 and 6.4 +/- 0.6 ms) corresponded to those of the SCPs recorded from the PES (4.6 +/- 0.3 and 6.3 +/- 0.5 ms), suggesting that these potentials reflect impulses conducting through the spinal cord, similar to epidurally recorded SCPs.

Adult↗
PubMed1996

A developmental defect in Plasmodium falciparum male gametogenesis.

Asexually replicating populations of Plasmodium parasites, including those from cloned lines, generate both male and female gametes to complete the malaria life cycle through the mosquito. The generation of these sexual forms begins with the induction of gametocytes from haploid asexual stage parasites in the blood of the vertebrate host. The molecular processes that govern the differentiation and development of the sexual forms are largely unknown. Here we describe a defect that affects the development of competent male gametocytes from a mutant clone of P. falciparum (Dd2). Comparison of the Dd2 clone to the predecessor clone from which it was derived (W2'82) shows that the defect is a mutation that arose during the long-term cultivation of asexual stages in vitro. Light and electron microscopic images, and indirect immunofluorescence assays with male-specific anti-alpha-tubulin II antibodies, indicate a global disruption of male development at the gametocyte level with at least a 70-90% reduction in the proportion of mature male gametocytes by the Dd2 clone relative to W2'82. A high prevalence of abnormal gametocyte forms, frequently containing multiple and unusually large vacuoles, is associated with the defect. The reduced production of mature male gametocytes may reflect a problem in processes that commit a gametocyte to male development or a progressive attrition of viable male gametocytes during maturation. The defect is genetically linked to an almost complete absence of male gamete production and of infectivity to mosquitoes. This is the first sex-specific developmental mutation identified and characterized in Plasmodium.

Animals↗
PubMed1996

Seroprevalence and specificity of human responses to the Plasmodium falciparum rhoptry protein Rhop-3 determined by using a C-terminal recombinant protein.

Rhoptry proteins participate in invasion of erythrocytes by malaria parasites. Antibodies to some of these proteins can inhibit invasion and partially protect monkeys from disease. To examine human serological responses to the 110-kDa component (Rhop-3) of the high-molecular-weight rhoptry protein complex, two cDNA clones corresponding to Rhop-3 were identified by immunologic screening. A recombinant protein representing the C-terminal one-third of the Rhop-3 was used to assess the seroprevalence to this protein in geographically isolated populations with different patterns of malaria transmission. The immunoglobulin G (IgG) positivity rate for the recombinant Rhop-3 in an enzyme-linked immunosorbent assay was 30% in an area of Papua New Guinea where malaria is holoendemic. In Kenya, the prevalence rates were 43 and 36%, respectively, in an area of hyperendemicity and an area of seasonal transmission. By contrast, rates of IgG seroprevalence to an extract of Gambian strain of Plasmodium falciparum were 48, 90, and 97% respectively, in these populations. In these areas, the pattern of antibody recognition of Rhop-3 is more similar (1.7-fold maximum difference) than the parasite extract (5-fold difference). The difference in seroresponses may represent antigenic polymorphism in different parasite strains, while their similarity for the Rhop-3 fragment may represent conservation of this protein. Recombinant- and parasite extract-specific IgG was not found in individuals infected only with Plasmodium vivax. Cross-reactivity was seen in the IgM assay. In Mombasa (Kenya), maternal and cord Rhop-3-specific IgG activities were similar. Fetal antigen-specific IgM reactivity was generally undetectable for all antigens.

Animals↗
PubMed1996

Antineutrophil cytoplasmic antibodies (ANCA)-associated crescentic glomerulonephritis and propylthiouracil therapy.

Cutaneous vasculitis is an uncommon complication of propylthiouracil therapy. Although its pathogenesis remains to be established, detection of antineutrophil cytoplasmic antibodies (ANCA) in association with this type of vasculitis has recently been described. We report here 2 patients who developed ANCA-associated crescentic glomerulonephritis without evidence of cutaneous vasculitis during propylthiouracil treatment of hyperthyroidism. Improvement of the renal function and the disappearance of ANCA were correlately found after discontinuation of propylthiouracil and by corticosteroid therapy in both patients.

Adult↗
PubMed1996

Release profiles of recombinant human tumor necrosis factor from Ca(2+)-triggering liposome in vivo.

After the administration of the recombinant human tumor necrosis factor (rHuTNF), plasma concentration could be controlled from egg yolk phosphatidylcholine (eggPC)-egg yolk phosphatidic acid (eggPA) liposome (EggPA liposome). The plasma concentration was highest after the rHuTNF solution administration. Although the concentration after the 30% EggPA liposome administration was much lower than that after the solution administration, the antitumor effect against Meth A sarcoma was equal to that of the rHuTNF solution. Non-linear elimination of rHuTNF in rat could explain these phenomena. First, to evaluate the intact absorption profile, we developed a non-linear absorption calculating program (NLAP). The calculation revealed little difference in the total absorption amounts between the solution and liposomes. The absorption rate from the liposomes was lower than that from the solution, and finally, the control of rHuTNF release from liposomes was also confirmed in vivo. These findings suggested that the sustained release of rHuTNF from liposomes maintained high drug concentration in the injected site and decreased the systemic drug concentration.

Animals↗
PubMed1996

Differential contribution of metal complexation and dimerization to the chemotherapeutic potential of bicyclen-Zn2II complex against human immunodeficiency virus.

1,1'-(m-Xylenediyl)-bis(1,4,7,10-tetraazacyclododecane)-Z n2II complex (m-xylenediyl-bicyclin-Zn2II), a potent inhibitor of human immunodeficiency virus (HIV), was obtained from cyclin by a combination of dimerization and metal complexation. The ratio of median cytotoxic concentration against host cells (CC50) and median effective concentration against HIV cytopathogenicity (EC50), referred to as the selectivity index (SI), was regarded to be a measure of anti-HIV activity. These two chemical modifications contributed to a potent, in vitro anti-HIV activity of m-xylenediyl-bicyclin-Zn2II by respectively increasing the CC50 and decreasing the EC50 in comparison with those of cyclin.

Antiviral Agents↗
PubMed1996

Ameloblastoma with prominent ossification in the mandible of a dog.

A rare case of ameloblastoma with prominent stromal ossification in an 8-year-old female dog was studied. A bony mass recurred rapidly in the right mandible at the first molar region. Histopathologic examination revealed the lesion to be an atypical variant of ameloblastoma. Epithelial cells showed marked cell atypia, and mitotic figures were rather common. The collagenous stroma was abundant, with prominent formation of bone trabecular rimmed by active osteoblasts. The tumor was highly proliferative and aggressive, and thought to be malignant in nature.

Ameloblastoma↗
PubMed1996

Effect of low dietary calcium intake on blood pressure and pressure natriuresis response in rats: a possible role of the renin-angiotensin system.

Dietary Ca is an important modulator of blood pressure in humans and rats. Since the kidney plays a key role in the pathogenesis of hypertension, the effects of a low Ca diet (0.01% Ca) on blood pressure and pressure natriuresis response were studied in normotensive Sprague-Dawley rats. In addition, a possible role of the renin-angiotensin system in the development of hypertension and an altered pressure natriuresis response resulting from low dietary Ca intake was examined. In the low Ca diet group, systolic blood pressure measured by the tail-cuff method was significantly higher than in the normal Ca diet group (1,1% Ca) 1 week after the diet (1 13.0 +/- 7.1 vs. 105.0 +/- 9.5mmHg, p < 0.05). After 4 weeks, the hypertension was more pronounced. Low dietary Ca intake significantly inhibited the water and sodium excretory responses to acute elevation of renal perfusion pressure by tightening an infrarenal aortic constriction. Treatment with an inhibitor of angiotensin-converting enzyme, captopril (30 mg/kg/day), completely abolished the elevation of blood pressure and attenuated the reduced pressure natriuresis response observed in Ca-deficient rats. Although plasma renin activity was not different between the low and normal Ca diet groups after the 2-week dietary regimen, the pressor response to angiotensin II was enhanced by 30% in the low Ca diet group and there was a significant difference in the pressor response between the two groups. These results suggest a possible involvement of the renin-angiotensin system in the development of hypertension and an inhibitory effect on the pressure natriuresis response caused by low dietary Ca intake, via an enhanced sensitivity to angiotensin II.

Analysis of Variance↗
PubMed1996

A correlation of the sequestration rate of Plasmodium coatneyi-infected erythrocytes in cerebral and subcutaneous tissues of a rhesus monkey.

Parasitized red blood cells (PRBCs) were sequestered in microvessels of cerebral and subcutaneous tissues of a rhesus monkey infected with Plasmodium coatneyi. A similar sequestration rate (approximately 80%) was observed in both cerebral and subcutaneous microvessels. Electron microscopy showed knobs of the sequestrated PRBCs cytoadhered to endothelial cells. These results are consistent with the finding of PRBC sequestration in subcutaneous tissues in a comatose patient with cerebral malaria. Biopsy specimens of subcutaneous tissue may be useful as indicators of PRBC sequestration in the brain of cerebral malaria patients.

Animals↗
PubMed1996

Multi-organ erythrocyte sequestration and ligand expression in rhesus monkeys infected with Plasmodium coatneyi malaria.

The pathogenesis of human cerebral malaria is suspected to be caused by blockage of cerebral microvessels by the sequestration of parasitized human red blood cells (PRBC). Examination of infected tissues indicate PRBC sequestration in microvessels is the result of PRBC knob attachment to endothelial cell surface cytoadherence receptors such as CD36, thrombospondin (TSP), and intercellular adhesion molecule-1 (ICAM-1). In lieu of fresh human tissue, several animal models for human cerebral malaria have been developed, the Plasmodium coatneyi-infected rhesus monkey model being the most versatile. To further the understanding of noncerebral malarial complications during disease, we examined noncerebral tissues of infected rhesus monkeys. Our study demonstrated similar microvessel PRBC sequestration and the presence of cytoadherence ligands in noncerebral tissues. Immunohistochemical analysis showed CD36, TSP, and ICAM-1 cytoadherence proteins in several major organs.

Animals↗