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Biomedical subjects

K Fujiki

Publications and source records attributed to K Fujiki.

At least 55 records · Page 3Linked to original sources

[A case of juvenile retinoschisis diagnosed by analysis of the XLRS 1 gene].

BACKGROUND: We report on a 3 year-old boy who was first diagnosed with retinal detachment and macular hole and received surgical treatment. X-linked juvenile retinoschisis was determined by DNA analysis. CASE: Past or family history was not recognized. There was left macular hole but no typical spoke-like foveal retinoschisis was observed in either eye. We could not diagnose the case as X-linked juvenile retinoschisis because there was no family history of it, central foveal reflex was observed in right eye with corrected visual acuity of 1.2, and no abnormality was recorded in the electroretinogram. High molecular weight DNA was extracted from peripheral leukocytes, and the XLRS 1 gene was analyzed. Hemizygous missense mutation, Arg102Gln, was detected. We diagnosed the disease as X-linked juvenile retinoschisis because the Arg102Gln mutation was detected in a family in Germany, two families in the United Kingdom, and two families in the USA. CONCLUSION: XLRS 1 gene analysis is useful if the diagnosis is difficult clinically due to atypical clinical findings.

Child, Preschool↗

Disappearance of hyperplastic polyps in the stomach after eradication of Helicobacter pylori. A randomized, clinical trial.

BACKGROUND: Helicobacter pylori infection is common in patients with hyperplastic gastric polyps. OBJECTIVE: To study the effect of eradication of H. pylori on the clinical course of patients with hyperplastic gastric polyps. DESIGN: Single-blind, randomized, controlled trial. SETTING: University-based gastroenterology outpatient clinic. PATIENTS: 35 patients with H. pylori infection and hyperplastic gastric polyps at least 3 mm in diameter. INTERVENTION: Patients were randomly assigned to a treatment group (n = 17), which received a proton-pump inhibitor (omeprazole or lansoprazole), amoxicillin, and either clarithromycin or ecabet sodium, or to a control group (n = 18), which received no treatment. MEASUREMENTS: Patients underwent endoscopy before enrollment and 12 to 15 months after the end of treatment. Serum gastrin levels and titers of IgG to H. pylori were measured. RESULTS: In the treatment group, the polyps had disappeared by 3 to 15 months (average, 7.1 +/- 1.2 months) after the end of treatment in 12 of all 17 patients (71%) and in 12 of the 15 patients (80%) in whom H. pylori was eradicated. However, 12 to 15 months after the start of the study, no change in polyps or H. pylori status was seen in any controls (P < 0.001). Histologic findings of inflammation and activity, serum gastrin levels, and titers of IgG to H. pylori showed significant regression in the treatment group compared with the control group (P < 0.01). CONCLUSIONS: Most hyperplastic polyps disappeared after eradication of H. pylori. Thus, eradication should be attempted before endoscopic removal is done in patients with hyperplastic gastric polyps and H. pylori infection.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Two diverged complement factor B/C2-like cDNA sequences from a teleost, the common carp (Cyprinus carpio).

Mammalian complement components factor B and C2 act as proteolytic subunits of the C3 convertases in the alternative and the classical activation pathways, respectively, and are believed to have diverged from a common ancestor by gene duplication. However, it is unclear when the B/C2 duplication occurred. Here, we describe two diverged B/C2-like cDNA clones (B/C2-A and B/C2-B) isolated from a bony fish, the common carp (Cyprinus carpio). B/C2-A shares the same domain structure as the factor B and C2 complement components of vertebrates reported so far and shows a close similarity to zebrafish B and medaka fish B/C2. These teleost sequences show almost the same degree of similarity to C2 and B of higher vertebrates. In contrast, B/C2-B has a novel structural feature in that it contains four short consensus repeat modules and does not have a close relative upon phylogenetic analysis. Northern blotting revealed the presence of two transcripts with different sizes for both the B/C2-A and B/C2-B in the hepatopancreas of the carp. Southern blotting suggested the presence of multiple genes for B/C2-A and a single gene for B/C2-B. Although structural features of B/C2-B are slightly more C2-like than B-like, B/C2-B has a crucial amino acid substitution in the serine protease domain, which makes it unlikely that B/C2-B functions as a C3 convertase. A possible phylogenetic relationship between the two carp sequences and mammalian C2 and B is discussed.

Amino Acid Sequence↗

Japanese juvenile retinoschisis is caused by mutations of the XLRS1 gene.

We investigated the XLRS1 gene in Japanese patients with retinoschisis (RS). All exons of the XLRS1 gene were sequenced in 14 males, including a pair of monozygotic twins, from 11 individual families with RS and five of their mothers who are asymptomatic but diagnosed as carriers. Six kinds of missense mutations and a nonsense mutation, including six novel mutations, were detected in all 14 patients and carriers. Mutations in the XLRS1 gene are also responsible for RS in non-Caucasian patients. Most Japanese RS cases are caused by an XLRS1 gene defect. A novel mutation, Glu72Lys, was found in four families, suggesting a common mutation in the Japanese population. Clinical features of RS patients with both the Glu72Lys and Pro193Leu mutations indicate that a genotype-phenotype correlation is not recognized in RS.

Eye Diseases, Hereditary↗

A new L527R mutation of the betaIGH3 gene in patients with lattice corneal dystrophy with deep stromal opacities.

Mutations in the betaIGH3 gene on chromosome 5q31 cause five distinct autosomal dominant corneal dystrophies: granular Groenouw type I, Reis-Bücklers', lattice type I and IIIA. and Avellino corneal dystrophies. We present here a new mutation of the betaIGH3 gene in patients with late-onset lattice corneal dystrophy manifest as a deep stromal opacity. To test the previously reported R124C, R124H, P501T, R555W, and R555Q mutations of the betaIGH3 gene, 30 patients and 11 normal relatives from 16 independently ascertained families with lattice corneal dystrophy, 49 patients and 12 normal relatives from 40 independently ascertained families with other corneal dystrophies, and 40 unrelated normal volunteers, were analyzed. A L527R (CTG/CGG) mutation of the betaIGH3 gene was found in 6 unrelated patients with lattice corneal dystrophy. A retrospective review of the patients' records showed that the opacities were deep in the stromal layer and of late onset. The mutation was a heterozygous single base-pair transversion from T to G of the second nucleotide position of codon 527. This caused the substitution of arginine for leucine. These six patients did not have mutations in codons 124, 501, or 555. The L527R mutation was not detected in the other corneal dystrophies or 40 normal volunteers. Although phenotypic variations in the size and shape of the deposits were found, all patients with the L527R mutation showed deposits deep in the stromal layer. We conclude that there are now at least six different mutations that have been detected in the betaIGH3 gene on chromosome 5q31 and that lead to corneal dystrophy.

Aged↗

Mitochondrial DNA mutations in Japanese patients with optic neuropathy unassociated with a mutation at nucleotide position 11,778.

We examined for mitochondrial DNA (mtDNA) mutations at nucleotide positions(nt) 3460, 14,484, 9438, 9804, and 15,257 in ten Japanese patients with idiopathic optic neuropathy unassociated with a mutation at nt11,778. The mtDNAs were amplified by polymerase chain reaction (PCR), the products were digested with restriction enzymes, and the sizes of the fragments were analyzed on 8% polyacrylamide gel. Of the ten patients, one had an mtDNA mutation at nt3460 and another patient had a mutation at nt14,484. We suggest that mtDNA mutations in Japanese patients with optic neuropathy unassociated with a mutation at nt11,778 should be further investigated.

Adolescent↗

Prospective evaluation of a new anti-ulcer agent, ecabet sodium, for the treatment of Helicobacter pylori infection.

BACKGROUND: A new anti-ulcer agent, ecabet sodium, is active against Helicobacter pylori. AIM: To assess the efficacy of ecabet sodium for the eradication of H. pylori in patients with gastroduodenal diseases. METHODS: In a prospective, randomized and controlled study, patients infected with H. pylori were assigned to one of the following two groups: group LA, who received lansoprazole 30 mg o.d. + amoxycillin 500 mg q.d.s. after meals for 2 weeks, and group LAE, who received lansoprazole 30 mg o.d. + amoxycillin 500 mg q.d.s. + ecabet sodium 1000 mg b.d. after meals for 2 weeks. H. pylori status was determined before and at least 4 weeks after the therapy by rapid urease test, histology and a urea breath test. RESULTS: Of 101 patients (mean age 53 years, range 17-77 years, M/F: 68/33) enrolled in the study, 97 patients completed the protocol. Four patients were withdrawn because of diarrhoea (three from group LA) and skin rash (one from group LAE). The eradication of H. pylori was achieved in 28/48 (58%) patients in group LA and 38/49 (78%) patients in group LAE. The rate of eradication of H. pylori produced by the LAE treatment was significantly higher than that produced by the LA treatment. Side-effects appeared in two patients (malaise 1, skin rash 1) in group LAE and in seven patients (diarrhoea 6, dizziness 1) in group LA. These side effects disappeared spontaneously with cessation of the treatment. CONCLUSIONS: Ecabet sodium in combination with lansoprazole and amoxycillin increased the rate of eradication of H. pylori. Ecabet sodium appeared to reduce the incidence of diarrhoea as a side-effect of the dual LA therapy.

Abietanes↗

Visual function in retinitis pigmentosa related to a codon 15 rhodopsin gene mutation.

To determine the phenotype of a Japanese family in which retinitis pigmentosa cosegregates with a rhodopsin gene mutation, i.e. an asparagine-to-serine change at codon 15 (Asn-15-Ser), 5 affected and 5 unaffected members of one pedigree underwent several ophthalmic examinations as well as Ganzfeld electroretinography (ERG) and multifocal ERG. Genomic DNA samples were analyzed by PCR amplification, sequencing and restriction enzyme digestion. A codon 15 rhodopsin gene mutation (Asn-15-Ser) was found in all affected members. The region of pigmentary degeneration was localized in the lower hemiretina, and visual field defects corresponded to the retinal pigmentary changes. Scotopic ERG amplitudes, rather than photopic ERG amplitudes, were reduced. Multifocal ERG revealed a low magnitude of response density, even for the upper hemiretina, which showed no bony corpuscle pigmentation. Visual function in sectorial retinitis pigmentosa associated with rhodopsin gene codon 15 mutation is on the basis of the rod-cone dystrophy, regardless of differences in phenotypic expression.

Adult↗

Homozygotic patient with betaig-h3 gene mutation in granular dystrophy.

PURPOSE: This study investigated patients with granular dystrophy and identified a homozygotic patient and his family with a mutation in the betaig-h3 gene. METHODS: Genomic DNAs were extracted from leukocytes of the peripheral blood of the proband, his parents, and his grandmother. All had granular dystrophy. Genomic DNAs from 50 unrelated normal volunteers were used as controls. Exon 4 of betaig-h3 gene was amplified and analyzed by direct sequence. Clinical data were collected. RESULTS: A single-base-pair transition was detected. This was a substitution of G to A of the second nucleotide position of codon 124 in the betaig-h3 gene that led to a replacement of histidine for arginine (Arg124His, CGC-->CAC). This mutation was the precise one previously reported for Avellino dystrophy. Although the proband was homozygotic for the mutant alleles, his grandmother, and parents were heterozygotic for these alleles. No sequence modification in the codon 124 from 50 nonaffected control individuals was detected. Clinical findings of the proband were severe. Keratectomies were performed for both his eyes 5 times for a 24-year period. His grandmother and parents showed mild clinical symptoms, had a few annular granules in the subepithelial stroma, and maintained good visual acuities. CONCLUSION: Arg124His mutation of the betaig-h3 gene was found in a pedigree with granular dystrophy. This mutation was the precise one previously reported for Avellino dystrophy. This fact shows an existence of Avellino form in Japanese. Homozygotic patient for mutant gene showed severe symptoms and an early onset.

Adolescent↗

[Relationship between visual field loss and retinal nerve fiber layer thickness in open-angle glaucoma].

We studied the correlation between retinal nerve fiber layer thickness and visual field loss in 117 eyes of 62 patients with open angle glaucoma using the Aulhorn Classification as modified by Greve. We divided the peripapillary area into four quadrants [superior (S), inferior (I), temporal (T), nasal (N)] and the total (T0), and measured the peripapillary retinal nerve fiber layer thickness (NFLT) with a confocal scanning laser polarimeter (Nerve Fiber Analyzer). We also obtained the relative ratios (mean ratios) of the total circumference to the nasal quadrant (T0/N), the superior to the nasal quadrant (S/N), the temporal to the nasal quadrant (T/N), the inferior to the nasal quadrant (I/N), the total to the temporal quadrant (T0/T), the superior to the temporal quadrant (S/T), the nasal to the temporal quadrant (N/T), and the inferior to the temporal quadrant (I/T). Significant decreases were observed in the mean ratios to the temporal quadrant, i.e., T0/T, S/T, and I/T, in stages I to VI when compared with stage 0. However, no significant differences were observed among stages I to VI. These results suggest that these parameters may not precisely reflect the progression of the disease, but may aid differential diagnosis of the early stage (stage 0) from the middle and late stages (stages I to VI).

Female↗

[Relationship between the retinal nerve fiber layer thickness and the effect of aging in normal eyes].

We studied the correlation between the thickness of the retinal nerve fiber layer and the role of age in 155 normal eyes of 83 subjects without significant ocular diseases. Subjects with a refractive error exceeding +/- 5 diopters were excluded. We divided the peripapillary area into four quadrants: superior (S), inferior (I), temporal (T), and nasal (N). We measured peripapillary retinal nerve fiber layer thickness (NFLT) in these four quadrants and in the total area (T(o)) using a confocal scanning laser polarimeter (Nerve Fiber Analyzer), and determined the correlation coefficients. The retinal nerve fiber layer thickness of the total area and of the four quadrants was not significantly associated with an increase in age. Since changes in the thickness were small in the nasal and temporal quadrants, we measured the relative ratios of the thickness in each quadrant to that in the nasal and temporal quadrants. The ratio of the total area to the nasal quadrant (T(o)/N), the superior to the nasal quadrant (S/N), the inferior to the nasal quadrant (I/N), the total area to the temporal quadrant (T(o)/T), the superior to the temporal quadrant (S/T), and the inferior to the temporal quadrant (I/T) was significantly associated with an increase in age. Multiple comparison in each age group revealed no age-related significant decreases in any of the parameters. These findings suggest that these parameters may reflect the degree of aging in normal eyes, but age-related abnormality in the retinal nerve fiber layer thickness may be small.

Adult↗

A hemizygous A to CC base change of the CHM gene causing choroideremia associated with pinealoma.

BACKGROUND: Although mutations of the CHM gene have been reported in the Caucasian patients with choroideremia, there have been no such reports in non-Caucasian patients. We analyzed the CHM gene in a Japanese patient with choroideremia associated with pinealoma. METHODS: The method for screening was a nonradioisotopic modification of single-strand conformation polymorphism (SSCP) analysis. The PCR products from the patient and the carrier were screened and directly sequenced using an automated DNA sequencer. The PCR product of the carrier was also subcloned into a vector and the subcloned products were sequenced. RESULTS: SSCP analysis showed an identical abnormal band shift in the patient and the carrier. Direct sequence analysis showed a hemizygous A to CC mutation at nucleotide 1608 of the CHM gene in the patient, suspected to result in the absence or truncation of the predicted CHM protein. The sequence using both the PCR product and the subcloned DNA of the carrier showed both wild-type and mutant bands indicating a heterozygote. CONCLUSION: The hemizygous mutation was detected in a patient and the heterozygous pattern in his mother, the carrier, suggesting that this mutation caused the disease.

Adaptor Proteins, Signal Transducing↗

Gastrointestinal autonomic nerve tumor with giant abscess. A case report and literature review.

We report a gastrointestinal autonomic nerve tumor of the stomach with a giant abscess. The patient had fever and pain and was found to have anemia and an abdominal mass. X-ray and endoscopic examination showed a gastric submucosal tumor with a fistula to the gastric lumen. Partial gastrectomy was performed and no metastasis was found. On gross examination, the excised tumor was seen to be a submucosal solid tumor with a giant abscess. Alpha streptococci and anaerobic gram-negative rods were cultured from the pus of the abscess. The tumor resembled a gastric myogenic tumor composed of spindle cells, partly showing storiform and epithelioids. Tumor cells showed positive staining for vimentin and neuron-specific enolase but were negative for desmin, alpha-smooth muscle actin, and S-100 protein. Ultrastructural examination showed remarkable interdigitation of cytoplasmic processes with neurosecretory granules between the tumor cells. This lesion was similar to previously described gastrointestinal autonomic nerve tumors. Gastrointestinal autonomic nerve tumors are a rare, distinct subtype of gastrointestinal stromal tumors; although several cases of focally necrotic tumors have been reported, there has been only one report of the tumor with an abscess, as in our case.

Abscess↗

Changes in serum pepsinogen, gastrin, and immunoglobulin G antibody titers in helicobacter pylori-positive gastric ulcer after eradication of infection.

There are no studies of changes in immunoglobulin G (IgG) titers to Helicobacter pylori, serum pepsinogen, and gastrin in patients with H. pylori-positive gastric ulcers. We investigated the effect of therapy for H. pylori-positive gastric ulcer on IgG titers to H. pylori, serum pepsinogen I and II, and gastrin. Thirty-six patients with H. pylori-positive gastric ulcer were treated with lansorazole and antibiotics for 2 weeks. Serum pepsinogen I and II concentrations, serum gastrin, and IgG titers to H. pylori were measured before treatment and then at 4 and 12 weeks after stopping the treatment. The presence or eradication of H. pylori was determined using the rapid urease test and by histologic H. pylori staining. For 19 patients in whom H. pylori had been successfully eradicated, the pepsinogen I/II ratio increased, pepsinogen II levels decreased, and the anti-H. pylori IgG decreased compared with the results from before therapy and with those from 4 and 12 weeks after therapy. Gastrin levels decreased compared with pretreatment results and those from 4 weeks after the end of treatment. In 17 patients in whom the therapy failed to eradicate H. pylori infection, there were no sequential significant changes in the pepsinogen I/II ratio or in the levels of pepsinogen I, pepsinogen II, anti-H. pylori IgG, and gastrin. A decrease in the serum levels of the IgG antibody to H. pylori and gastrin and also an increase in the pepsinogen I/II ratio could be used as predictors for the eradication of H. pylori infection in gastric ulcer.

Aged↗

Studies on the mechanism of early onset macular degeneration in cynomolgus (Macaca fascicularis) monkeys. I. Abnormal concentrations of two proteins in the retina.

Cynomolgus (Macaca fascicularis) monkeys from three families, which showed symptoms of early onset macular degeneration was studied. Two proteins, albumin and glyceraldehyde 3-phosphate dehydrogenase, were found to have markedly altered concentrations in whole retina of the monkeys with early onset macular degeneration, compared with normal controls. SDS-polyacrylamide gel patterns detected a 40-70% increase in the concentration of albumin and about 65% decrease in the concentration of glyceraldehyde 3-phosphate dehydrogenase in these affected retinas. There was however no significant difference in the relative concentrations of albumin in the plasma samples of affected and normal monkeys belonging to the three families studied and to an unrelated family. These initial findings suggest that degradative as well as antioxidant enzymes might be involved in the mechanisms leading to macular degeneration. In addition, the results also correlate with a possible role of these two proteins in H2O2 toxicity and appear to indicate that oxidative stress is significant in the etiology of early onset macular degeneration.

Albumins↗

Studies on the mechanism of early onset macular degeneration in cynomolgus monkeys. II. Suppression of metallothionein synthesis in the retina in oxidative stress.

Initial investigations done in this laboratory detected increased albumin and decreased glyceraldehyde 3-phosphate dehydrogenase concentrations in the retina of an animal model manifesting early onset macular degeneration. Both glyceraldehyde 3-phosphate dehydrogenase and albumin are markers of oxidative stress in cells. In this study, we used the same animal model to study further biochemical and physiological processes which may be involved in the pathogenesis of early onset macular degeneration in monkeys. We detected 60% lower catalase and glutathione peroxidase activities in the affected retinas suggesting lower antioxidant activities and oxidative stress. One of the consequences of oxidative stress is the production of metallothionein, a low molecular weight protein also induced by high concentrations of heavy metals such as zinc. Metallothionein was detected by RT-PCR in these monkey retinas. However initial quantitative PCR studies on this protein showed that the synthesis of metallothionein in affected retinas appears to be less than in normal controls. The affected retinas also showed a fourfold lower zinc concentration compared with the normal controls. No significant difference, however, could be detected in the zinc concentrations in plasma samples. Since induction of metallothionein synthesis is mediated by transcription factors which require heavy metals such as zinc for binding to specific sites in the DNA, the lowered zinc concentration may, thus, correlate with the lowered metallothionein expression. And since metallothionein is suggested to function as a free radical scavenger, the lowered metallothionein synthesis may consequently contribute to increased peroxidation reactions in the affected retinas. It appears therefore, that oxidative stress and the decreased metallothionein synthesis may be involved in the pathogenesis of early onset macular degeneration in this animal model.

Amino Acid Sequence↗

Analysis of phosducin as a candidate gene for retinopathies.

Phosducin, a retina-expressed gene mapped to chromosome 1q25-32.1, was analyzed as a candidate gene for retinopathies. The phosducin gene was cloned and characterized, and PCR primers were designed. Eighty-three patients with various retinopathies and 45 control subjects (24 American, 21 Japanese) were analyzed for mutations in the phosducin gene by PCR, denaturing gradient gel electrophoresis (DGGE), and sequencing. A heterozygous sequence variant changing a glycine to arginine at codon 178 was found in one Usher syndrome type II (USH2) patient, while the other USH2 patients did not show any coding sequence variant. A heterozygous sequence variant changing an asparagine to lysine at codon 174 was found in a patient with a severe retinal degeneration in the category of diseases known as acute zonal occult outer retinopathy (AZOOR). Three non-coding sequence variants were found. Two of these were always present together and found in 20.8% of American and 2.4% of Japanese control subjects, reflecting a difference in population pools. In conclusion, the phosducin gene did not show mutations consistent with it being the causative gene for USH2, but its possible pathogenicity in AZOOR or other retinopathies remains an open question which may be answered by further analysis.

Base Sequence↗