Search PubMed⌕ Search

Biomedical subjects

K Fukai

Publications and source records attributed to K Fukai.

At least 19 recordsLinked to original sources
PubMed2006

Bilateral segmental neurofibromatosis with gastric carcinoma.

Neurofibromatosis type 1 (NF1) is an autosomal-dominant disorder characterized by café-au-lait spots, neurofibromas, intertriginous freckles, and Lisch nodules in the iris. Segmental neurofibromatosis is fundamentally a mosaic variant of NF1. A 66-year-old man visited us with bilateral segmental neurofibromatosis (SN) on the torso. He had multiple neurofibromas on the back bilaterally and on the right abdomen, and partial unilateral lentiginosis on the left abdomen and left back. The patient had noticed the development of papules and nodules on the right abdomen and bilaterally on the back 6 years previously, and had been diagnosed with early gastric carcinoma 5 years previously. To our knowledge, this is only the third reported case of SN associated with internal malignant tumours.

Aged↗
PubMed2005

A case of acquired smooth muscle hamartoma of the scrotum.

We report a case of acquired smooth muscle hamartoma (ASMH) of tunica dartos, believed to be only the fifth so far reported. A 24-year-old man had a 6-month history of an asymptomatic tight and thickened scrotum. The skin was difficult to pinch. A biopsy specimen from the skin showed increased and proliferated smooth-muscle bundles composed of well-differentiated and uniform spindle cells that showed typical features of acquired smooth muscle hamartoma. Interestingly, dilatations of the lymph vessels were noted in the upper dermis above the proliferated smooth muscles. It has been reported recently that long-standing severe lymphoedema may cause histological features mimicking ASMH. As the present case was not preceded by oedema of the scrotum, we consider this case to be true ASMH.

Adult↗
PubMed2004

Hepatitis B virus X protein (HBx)-induced apoptosis in HuH-7 cells: influence of HBV genotype and basal core promoter mutations.

BACKGROUND: Hepatitis B virus (HBV) infection is a serious, world-wide problem. HBV genotype and basal core promoter (BCP) mutations affect the clinical course of HBV-infected patients. BCP mutations also lead to mutations at HBV X protein (HBx) codons 130/131. The functional significance of naturally occurring variants of human HBx remains largely unknown. The purpose of the study was to investigate whether HBV genotypes or double mutations affect HBx-induced apoptosis. METHODS: We constructed genotype A, B, C, and D HBx expression vectors and HBx expression vectors with double mutations at HBx codons 130K and 131V or positions 130M and 131I using site-directed mutagenesis. A transient expression system in HuH-7 cells was established and this model was utilized to address the effect of HBx on cell viability. RESULTS: HBx-transfected cells showed a dose-dependent decrease in cell viability by MTS assay. A subset of cells expressing HBx underwent apoptosis according to terminal transferase enzyme-mediated end labeling of DNA and caspase-3 activity. This study demonstrated that HBx can induce cell death by apoptosis in a dose-dependent manner and that HBV genotypes and double mutations did not affect HBx-induced apoptosis. CONCLUSIONS: HBV genotypes and mutation of two amino acids directly adjacent to the conserved Kunitz domain essential for transcription activating activity of HBx did not change the pro-apoptotic activity of HBx. Further study is needed to determine whether HBV genotypes and double mutations have any effect on the function of HBx.

Apoptosis↗
PubMed2004

Molecular heterogeneity in two families with auditory pigmentary syndromes: the role of neuroimaging and genetic analysis in deafness.

We report two cases in which the probands presented with deafness and a family history of a dominantly inherited auditory pigmentary syndrome, yet the cause of deafness in each proband was not associated with the pigmentary abnormalities but was a result of mutations in SLC26A4, the gene mutated in Pendred's syndrome. The first case is a young woman with congenital sensorineural hearing loss and a family history of piebaldism. Despite showing no pigmentary abnormalities, the proband was found to harbor the same KIT mutation as her relatives affected by piebaldism, as well as two mutations in the SLC26A4 gene. In the second case, 2-year-old identical twin boys born to deaf parents presented with congenital sensorineural deafness and an extensive maternal family history of Waardenburg's syndrome type I (WSI). Their father had recessively inherited deafness associated with dilated vestibular aqueducts and a clinical diagnosis of Pendred's syndrome was made in him, which was confirmed molecularly. As the twin boys did not have features of WSI, both the mother and children were tested for mutations in SLC26A4 which showed the mother to be a carrier of a single mutation and both boys to be compound heterozygotes, illustrating pseudodominant inheritance of the condition.

Adult↗
PubMed2004

Mild phenotype of familial cylindromatosis associated with an R758X nonsense mutation in the CYLD tumour suppressor gene.

Familial cylindromatosis is a rare dominantly inherited disease characterized by the development of multiple benign tumours of the skin appendages, including cylindromas, trichoepitheliomas and spiradenomas. The gene responsible was positionally cloned recently, and was designated CYLD. We describe a family with cylindromatosis, in which affected individuals have an inherited R758X nonsense mutation of CYLD. Affected members of this family manifest a relatively mild tumour phenotype; the largest tumour was only 30 mm in diameter. Thus far, there is no evident genotype-phenotype relationship in cylindromatosis, although the number of families reported with both phenotypic and genotypic data remains small.

Adult↗
PubMed2003

Angelman syndrome associated with oculocutaneous albinism due to an intragenic deletion of the P gene.

Angelman syndrome (AS) is a neurodevelopmental disorder characterized by mental retardation, speech impairment, ataxia, and happy disposition with frequent smiling. AS results from the loss of expression of a maternal imprinted gene, UBE3A, mapped within 15q11-q13 region, due to different mechanisms: maternal deletion, paternal UPD, imprinting center mutation, and UBE3A mutation. Deletion AS patients may exhibit hypopigmentation of skin, eye, and hair correlating with deletion of P gene localized in the distal part of Prader-Willi (PWS)/AS region. Our patient presented developmental delay, severe mental retardation, absence of speech, outbursts of laughter, microcephaly, ataxia, hyperactivity, seizures, white skin, no retinal pigmentation, and gold yellow hair. His parents were of African ancestry. The SNURF-SNRPN methylation analysis confirmed AS diagnosis and microsatellite studies disclosed deletion with breakpoints in BP2 and BP3. All of the 25 exons and flanking introns of the P gene of the patient, his father, and mother were investigated. The patient is hemizygous for the deleted exon 7 of the P gene derived from his father who is a carrier of the deleted allele. Our patient manifests OCA2 associated with AS due to the loss of the maternal chromosome 15 with the normal P allele, and the paternal deletion in the P gene. As various degrees of hypopigmentation are associated with PWS and AS patients, the study of the P gene in a hemizygous state could contribute to the understanding of its effect on human pigmentation during development and to disclose the presence of modifier pigmentation gene(s) in the PWS/AS region.

Albinism, Oculocutaneous↗
PubMed2003

Association of SPINK5 gene polymorphisms with atopic dermatitis in the Japanese population.

BACKGROUND: Netherton's syndrome (NS) is an autosomal recessive disorder characterized by trichorrhexis invaginata ('bamboo hair'), congenital ichthyosiform erythroderma and an atopic diathesis. NS has recently been shown to be due to a defect in the SPINK5 gene, encoding LEKTI, a 15-domain serine protease inhibitor. SPINK5 maps to chromosome 5q31-q32, and has been suggested to be a locus predisposing to atopy in general. Recently, coding polymorphisms in SPINK5 exons 13 and 14 have been reported to be associated with atopy, asthma and atopic dermatitis (AD). OBJECTIVES: To examine whether these polymorphisms are also associated with AD in Japan. METHODS: We characterized eight polymorphisms in SPINK5 exons 13 and 14 in 124 Japanese patients with AD and 110 healthy controls. The polymorphisms we examined were IVS12-26C-->T, IVS12-10A-->G, 1103A-->G (Asn368Ser, in exon 13), 1156G-->A (Asp386Asn, in exon 13), 1188T-->C (His396His, in exon 13), IVS13-50G-->A, 1258G-->A (Glu420Lys, in exon 14) and IVS14+19G-->A. RESULTS: We found significant associations between seven of these polymorphisms and AD in Japanese patients. CONCLUSIONS: This study confirms the previous suggestion of an association between SPINK5 and AD.

Adolescent↗
PubMed2003

Guttate morphoea in human T-cell lymphoma/lymphotrophic virus type-1 (HTLV-1) infection.

A 62-year-old Japanese man presented with multiple small atrophic macules on the trunk and extremities. The lesions were discrete, oval in shape and enclosed by lilac ring. They were distributed in a Christmas tree distribution, reminiscent of pityriasis rosea. Skin biopsy showed increased collagen fibres in the dermis and invading subcutaneous tissue. The clinico-pathological features were consistent with guttate morphoea, a rare variant of localized scleroderma. Serological tests revealed a positive reaction to human T-cell lymphoma/lymphotropic virus type-1 infection.

Biopsy↗
PubMed2003

Distribution of hepatitis B viral genotypes and mutations in the core promoter and precore regions in acute forms of liver disease in patients from Chiba, Japan.

BACKGROUND: Although it has been reported that different hepatitis B virus (HBV) genotypes induce different clinical characteristics in patients with chronic liver diseases (CLD), there have been few reports that have detailed the distribution of HBV genotypes in acute forms of liver disease. METHODS: HBV genotypes were determined in 61 patients who had acute forms of liver disease (45 had acute self limited hepatitis (AH) and 16 had fulminant hepatitis (FH)) and in 531 patients with CLD, including 19 patients with severe acute exacerbation of CLD. We also analysed the enhancer II, core promoter, and precore region sequences for the presence of mutations. RESULTS: Expression of genotype B in patients with acute forms of liver disease was significantly greater than in those with CLD (39.3% v 11.7%, respectively; p<0.001). Furthermore, expression of genotype B was significantly greater in patients with FH than in those with AH (62.5% v 31.1%, respectively; p=0.027). The precore mutation A1896 and the core promoter mutation at nt 1753 and 1754 were found more frequently in FH than in AH, and genotype B was predominant in FH regardless of the presence of these mutations. CONCLUSIONS: HBV genotype B was found more frequently in patients with acute forms of liver disease than in patients with CLD, and more frequently in patients with FH than in those with AH. These results suggest that this HBV genotype may induce more severe liver damage than other viral genotypes, at least in patients from Chiba, Japan.

Acute Disease↗
PubMed2002

Changes in the prevalence of rotavirus G and P types in diarrheic calves from the Kagoshima prefecture in Japan.

G8 bovine group A rotavirus was the most predominant serotype in calf diarrheal fecal specimens examined between 1995 and 1996 in Japan [Vet. Microbiol. 66 (1999) 301]. To date, no evidence that G8 was the most predominant in the typeable specimens has been observed outside Japan. To investigate whether G8 continues to be as common as G6 and G10, the incidence of the main serotypes was determined in the same area (Kagoshima prefecture) between 1997 and 1998 by reverse transcription-polymerase chain reaction. From a total of 104 rotavirus-positive specimens, we successfully identified G type in 79 (76.0%) and P type in 71 (68.3%). The combination of G and P types varied periodically; in 1995, G10P[11] was most common. The most predominant types changed drastically in 1996, and G8 and mixed P types were the most predominant. A dramatic shift of the most predominant type occurred again in 1997 when G6P[5] was most common. This frequency of G6P[5] also continued in 1998. These results suggest that the serotypes prevailing in certain areas change periodically.

Animals↗
PubMed2001

Analysis of the complete genome of indigenous swine hepatitis E virus isolated in Japan.

Using reverse transcription-polymerase chain reaction with primers derived from well-conserved genomic areas among all four hepatitis E virus (HEV) genotypes (I-IV), the HEV sequence was identified in serum samples obtained from 3 (3%) out of 95 60- to 90-day-old pigs in Japan and characterized molecularly. In the partial sequence of open reading frame (ORF) 2 of 421 nucleotides, the three swine isolates (swJ570, swJ681, and swJ791) showed the highest similarity of 83-87% to genotype III HEV representing human and swine strains (US1, US2, and swUS1) in the United States. The full-length nucleotide sequence of swJ570 consisted of 7225 nucleotides excluding the poly(A) tail and contained ORF 1 encoding 1703 amino acids (aa), ORF2 encoding 660 aa, and ORF3 encoding 122 aa. The swJ570 strain was most closely related to a Japanese strain (JRA1), which had been obtained from a hepatitis patient who had not traveled outside Japan. The overall nucleotide sequence identity between them was 89% and the deduced amino acid sequence identities of ORF1, ORF2, and ORF3 were 96, 99, and 98%, respectively. These results indicate that a certain proportion of pigs in Japan are HEV-viremic and may act as reservoirs of HEV infection, and that the presence of an indigenous strain(s) of HEV should be taken into consideration for the diagnosis of acute hepatitis in Japan.

3' Untranslated Regions↗
PubMed2001

Duplication of 15q11.2-q14, including the P gene, in a woman with generalized skin hyperpigmentation.

We describe a woman with 15q11.2-q14 duplication who had clinical manifestations of proximal 15q trisomy and hyperpigmentation. Within this region, the P gene, located at chromosome segment 15q11.2-q12, is associated with oculocutaneous albinism type II (OCA2) and with hypopigmentation in the Prader-Willi and Angelman chromosome 15q deletion syndromes. We therefore hypothesized that in this woman skin hyperpigmentation might result from a duplication of the P gene. We carried out chromosomal and interphase fluorescence in situ hybridization (I-FISH) analyses, and determined that the P gene is duplicated in this woman. Our findings demonstrate that trisomy of the P gene can be associated with skin hyperpigmentation.

Carrier Proteins↗
PubMed2001

Analysis of full-length hepatitis A virus genome in sera from patients with fulminant and self-limited acute type A hepatitis.

BACKGROUND/AIMS: Type A hepatitis still poses a considerable problem worldwide. Why some patients progress to fulminant type A hepatitis and others do not is still unknown. To examine whether genomic differences of hepatitis A virus (HAV) are responsible for the severity of the disease, we analyzed the whole HAV genomes from patients with fulminant and self-limited acute type A hepatitis. METHODS: Sera from three patients with sporadic type A fulminant hepatitis (FH) and three patients with acute hepatitis (AH) were examined for HAV RNA. Full-length nucleotide sequences were determined using long reverse transcription polymerase chain reaction, 5' and 3' rapid amplification of cDNA ends methods, and direct sequencing. The amino acid sequences were deduced from the nucleotide sequences. RESULTS: HAV RNA was detected in all six patients examined. From the sequence of viral protein 1/2A, all cases were revealed to be genotype IA. By comparing with genotype IA, wild-type HAV strain GBM, the analysis of whole genomes from the six cases showed no specific substitutions between FH and AH. Completely identical nucleotide sequences were observed at 3' non-translated region (NTR) in all six cases. In 5'NTR, less nucleotide substitutions were found in FH than in AH, and in the non-structural protein 2B region, a little more amino acid substitutions seemed to be found in FH than in AH. CONCLUSIONS: This study showed that full-length HAV could be analyzed from serum samples. Although there were no unique nucleotide or amino acid substitutions, possible associations were suggested between the severity of type A hepatitis and the nucleotide substitutions in 5'NTR and the amino acid substitutions in 2B.

3' Untranslated Regions↗