Search PubMed⌕ Search

Biomedical subjects

N Matsuo

Publications and source records attributed to N Matsuo.

At least 127 records · Page 7Linked to original sources
PubMed1997

Hepatic dysfunction in two sibs with Alström syndrome: case report and review of the literature.

Alström syndrome is an autosomal recessive disorder (MIM No. *203800) characterized by retinal degeneration, obesity, deafness, noninsulin-dependent diabetes mellitus, and nephropathy. We report two sibs with Alström syndrome and hepatic dysfunction. The first sib developed elevations in liver enzymes at 29 years of age. Liver biopsy showed fatty liver, lymphocytic infiltration, and piecemeal necrosis. The second sib had had elevated gamma-glutamyltransferase levels since she was 10 years old. She developed ascites, esophageal varices, and splenomegaly in her twenties. Cirrhosis was confirmed by autopsy; the patient was 26 years of age at death. Three Alström syndrome patients with hepatic dysfunction have been documented previously. No specific cause was identified for liver disease in any of the patients, including ours. Hepatic dysfunction appears to be a manifestation of Alström syndrome.

Abnormalities, Multiple↗
PubMed1997

Correlation between human papillomavirus positivity and p53 gene overexpression in adenocarcinoma of the uterine cervix.

In the pathogenesis of cervical squamous cell carcinoma, an inverse correlation between human papillomavirus (HPV) infection and mutation of the p53 anti-oncogene has been suggested. Much less is known of a possible correlation in the case of adenocarcinoma of cervix. Twenty-five cervical adenocarcinomas and 7 adenosquamous carcinomas were analyzed for presence of HPV DNA sequences and overexpression of the p53 gene. Polymerase chain reaction revealed that 11 were positive for HPV DNA (34%). Seven were positive for HPV 16 and 5 for HPV 18. A mixed infection with HPV 16 and 18 was observed in 1 case. Patients with HPV-positive carcinoma were significantly younger than those with HPV-negative carcinoma (43 +/- 13.3 years versus 57 +/- 17.4 years, P = 0.01). Immunohistochemical staining showed that p53 was overexpressed in 11 of 32 cases (34%). Overexpression of the p53 gene was found in only 1 of 11 HPV-positive cases (9%) yet was evident in 10 of 21 HPV-negative cases (48%). This inverse association was statistically significant (P < 0.05). Prognostic analysis revealed that HPV-negative adenocarcinomas had a poorer prognosis than HPV-positive cases (P < 0.01) and that tumors with p53 overexpression also had a poorer prognosis than those without such overexpression (P < 0.01). Our observations suggest that HPV-negative or p53-positive adenocarcinomas may be a biologically distinct subset with a poorer prognosis.

Adenocarcinoma↗
PubMed1997

Microvascular change of the anterior eye segment after tenotomy in the rabbit.

BACKGROUND: The microvascular changes secondary to anterior segment ischemia following tenotomy of the extraocular muscles have not been studied in the rabbit. METHODS: Using scanning electron microscopy of methyl-methacrylate ocular microvascular luminal castings, the anterior eye segment vasculature after tenotomy was documented and compared to that after occlusion of the bilateral long posterior ciliary arteries and that in the eyes that were not subjected to any surgical intervention. RESULTS: Five days and 1 week after the surgical intervention with tenotomy, microvascular change secondary to the anterior segment ischemia was not apparent, but 2 weeks after the tenotomy subtle evidence of ischemia such as new vessels in the iris was observed. Seven weeks after tenotomy, marked microvascular change was observed where corneal new vessels arose from the superior perilimbal arteries. In contrast, we found prominent microvascular changes 2 weeks after the occlusion of the long posterior ciliary arteries. CONCLUSIONS: Tenotomy of the rabbit eye causes microvascular change similar to that in occlusion of the long posterior ciliary arteries. This result suggests that the anterior ciliary artery of the rabbit contributes blood flow to the anterior eye segment and also has a stronger connection with the long posterior ciliary artery than previously reported.

Animals↗
PubMed1997

Simultaneous identification of eye fixation related potentials and reaction related potentials from single-trial signals.

To obtain the effective components from event related potentials (ERPs), it has been necessary to average the waveforms of several trials. ERP data reflect the psychophysiological state of a subject. Time variation is an important feature in ERP analysis, and so the single-trial method is required. A method is proposed to identify simultaneously both eye fixation related potentials (EFRPs) and reaction related potentials (RRPs) using wavelength transforms. The EFRP is an ERP associated with saccadic eye movement. The RRP is defined as a component similar to P300 gained from the reaction signal. Six subjects participate in the oddball task. The task takes 30 min for each subject. Electroencephalograms (EEGs), electro-oculograms (EOGs) and electromyograms (EMGs) are simultaneously recorded. The EFRP is extracted for the offset of saccade from EOG, and the RRP is extracted for the onset of reaction from EMG. The results show that the estimated waveforms described well each of the components in the EFRP and RRP. Moreover, the simulation results show that the amplitudes of the lambda wave are estimated to within an error of 4%, and those of the latencies are within 0.4%, with an SNR of 4.5dB. Those of P300 were 11 and 4%, respectively. The reliability of the method is proved to be sufficient for estimating ERPs.

Electroencephalography↗
PubMed1997

Cataract and aqueous flare levels in patients with atopic dermatitis.

PURPOSE: To determine whether cataract in patients with atopic dermatitis is associated with higher levels of aqueous flare or cells. METHODS: In a prospective study, 35 consecutive patients examined during a 6-month period at the atopic dermatitis service in a university hospital underwent standardized ophthalmologic evaluations including the quantitative measurement of aqueous flare and cells by a laser flare-cell meter. RESULTS: Seven patients had bilateral cataract with anterior or posterior subcapsular opacities, or both; one patient had similar cataract in one eye and no cataract in the opposite eye; and 27 patients had no cataract in either eye. Fifteen eyes with cataract showed significantly higher levels of aqueous flare (2.1 to 33.9 photon counts per millisecond with a median of 18.0) compared with 55 eyes without cataract (2.4 to 16.0 photon counts per millisecond with a median of 9.2; Mann-Whitney U test, P = .0008). The association of cataract with higher levels of aqueous flare remained significant when only one eye (the right eye) of each patient was chosen for statistical analysis (P = .0024). CONCLUSION: Higher levels of aqueous flare caused by the breakdown of blood-aqueous barrier may contribute to the formation of cataract in patients with atopic dermatitis.

Adolescent↗
PubMed1997

Bilateral iridocyclitis with retinal capillaritis in juveniles.

PURPOSE: The authors present clinical features of 18 juvenile patients with a new type of uveitis termed bilateral iridocyclitis with retinal capillaritis (BIRC). METHODS: The authors reviewed medical records of 18 consecutive patients who showed bilateral iridocyclitis with retinal capillary leakage but no systemic manifestations during an 11-year period from January 1985 to December 1995. RESULTS: Twelve of the 18 patients were female and the age at onset ranged from 9 to 17 years old. All patients had many cells in the anterior chamber and anterior vitreous, together with mutton fat keratic precipitates. Fluorescein angiography showed leakage from the optic disc and retinal capillaries, mainly in the midperiphery, which corresponded to retinal cloudiness. Macular edema was minimal, and all patients maintained good vision. The inflammation responded well topical, oral, and intravenous administration of corticosteroids, the choice of which was based on the extent of retinal inflammation. Human leukocyte antigen (HLA)-DR6 and HLA-Cw7 were associated significantly with the presence of BIRC (chi square test, P < 0.0001). CONCLUSIONS: Bilateral retinal capillaritis affecting capillaries in various areas of the retina and overlying retinal cloudiness with no distinct lesions are unique to these patients. Fluorescein angiography is essential for diagnosis of BIRC.

Acute Disease↗
PubMed1997

Effect of tea polyphenols on histamine release from rat basophilic leukemia (RBL-2H3) cells: the structure-inhibitory activity relationship.

We studied the effect of tea polyphenols on histamine release from rat basophilic leukemia (RBL-2H3) cells. Among tea polyphenols, (-)- epigallocatechin gallate (EGCG) most strongly and dose-dependently inhibited histamine release from cells stimulated with a calcium ionophore, A23187. (-)-Epigallocatechin (EGC) and (-)-epicatechin gallate (ECG) with a triphenol residue moderately inhibited histamine release, whereas diphenolic (+)-catechin (C) and (-)-epicatechin (EC) did not. The magnitude of the inhibitory effect was in the order EGCG > ECG > EGC. Among simple polyphenols, the triphenol compounds, pyrogallol (PG) and gallic acid (GA) exerted inhibitory activity, but the diphenols, pyrocatechol, hydroquinone, and resorcinol did not. In addition, the mixture of PG and GA inhibited histamine release as strongly as EGCG with two triphenol residues. Similarly, they inhibited histamine release induced by IgE-antigen complex stimulation more efficiently than that induced by A23187 stimulation. EGCG did not inhibit the increase of intracellular Ca2+ in RBL-2H3 cells stimulated with A23187 or IgE antigen. These results indicate that the triphenol structure plays an important role in the inhibitory activity of tea polyphenols. Their activity seemed to be exerted through the metabolic events occurring after the elevation of intracellular Ca2+ concentration.

Animals↗
PubMed1997

Genetic analysis of hypophosphatasia.

A review is presented of the recent advances in: (i) clinical features, (ii) biochemistry and molecular biology of alkaline phosphatase, (iii) genetic defect in hypophosphatasia, and (iv) prenatal diagnosis. Despite the recent progress, the pathogenesis of hypophosphatasia is far from being elucidated. More clinical cases and further characterization of the alkaline phosphatase gene mutations are needed for better understanding of the clinical spectrum of the entity.

Adult↗
PubMed1997

Vibrio sp. strain NM 10, isolated from the intestine of a Japanese coastal fish, has an inhibitory effect against Pasteurella piscicida.

Vibrio sp. strain NM 10 with an inhibitory activity against Pasteurella piscicida K-III was isolated from the intestine of a spotnape ponyfish (Leiognathus nuchalis). This bacterium efficiently produced an antibacterial substance after growth at 20 degrees C for 24 h on 1/5 PYBG agar prepared with 50% seawater at pHs of 7.5 to 9.0. The antibacterial substance was heat labile and proteinaceous, with a molecular mass of less than 5 kDa, possibly a bacteriocin or a bacteriocin-like substance.

Animals↗
PubMed1997

The Y specific growth gene(s): how does it promote stature?

Although the presence of a Y specific growth gene(s) (Y growth gene(s) on Yq has widely been accepted, it remains unknown how this gene promotes stature. In this report, we discuss the growth pattern in normal boys and girls and in patients with growth disorders informative for the Y growth gene(s). The results suggest that the Y growth gene(s) augments statural growth by controlling the sex steroid independent childhood growth pattern.

Adolescent↗
PubMed1997

Impaired male sex development in an infant with molecularly defined partial 9p monosomy: implication for a testis forming gene(s) on 9p.

This paper describes a genetically male infant with impaired male sex development and partial 9p monosomy. The external genitalia were ambiguous with microphallus (penile length at birth 10 mm, mean age matched normal length 29 mm (SD 5)), hypospadias, and hypoplastic scrotum. The tests were undescended and severely hypoplastic (testis size at 12 months of age, right 8 x 5 x 4 mm and left 4 x 3 x 2 mm; mean age matched normal size, length 18 mm (SD 2), width 11 mm (SD 1). Cytogenetic studies showed a 46,XY,del(9)(p23) karyotype in all the 30 peripheral lymphocytes and 20 skin fibroblasts examined. Microsatellite analysis for a total of 13 loci assigned to the 9p22-24 region showed that the deleted chromosome 9 was of paternal origin and was missing a region distal to D9S168. Southern blot analysis for D9S47 also confirmed the 9p deletion. The sequence of SRY was normal. The results provide further support for the previously proposed hypothesis that a gene(s) for testis formation is present on the distal part of 9p and indicate in molecular terms that the putative testis forming gene(s) resides in the region distal to D9S168.

Blotting, Southern↗
PubMed1997

Testicular histopathology in congenital lipoid adrenal hyperplasia: a light and electron microscopic study.

This paper describes the testicular histopathology in 2 male patients with congenital lipoid adrenal hyperplasia who underwent orchiectomy at age 7 (case 1) and 12 (case 2) years, respectively. In both cases, seminiferous tubules were normal in diameter (mean: case 1 88.7 microm; case 2 115.9 microm) and consisted of an age-appropriate number of type A spermatogonia (mean: case 1 1.7/tubule; case 2 4.0/tubule) and an increased number of Sertoli cells (mean: case 1 34.7/tubule; case 2 27.9/tubule). The interstitial space was abundant and contained normal to increased numbers of Leydig cells (mean: case 1 4.0/ tubule; case 2 6.1/tubule) that were filled with lipid droplets. We suspect that lipid accumulation in Leydig cells is consistent with defective conversion of cholesterol into pregnenolone and thus constitutes the characteristic feature of this disease, while the remaining findings appear to be common to disorders associated with hypergonadotropic hypogonadism.

Adrenal Hyperplasia, Congenital↗
PubMed1997

Reconstruction of trabecular tissue from human trabecular cells as a multicellular spheroid.

To understand the development of the trabecular meshwork of the eye, floating cellular aggregates (multicellular spheroids) were formed from human trabecular cells in a non-adherent environment of culture and incubated for up to one month. Dissociated trabecular cells formed multicellular spheroids within one day in the non-adherent environment, and apoptosis continued to occur in the spheroids which had been initially filled with cells. The final structure after one month appeared as a meshwork of cells with large extracellular spaces. Epidermal and basic fibroblast growth factor (EGF and bFGF) protected trabecular cells in the spheroids from apoptosis and, as a result, kept the spheroids filled with cells even after one month. In the absence of excess EGF or bFGF, the multicellular spheroids grown in vitro from human trabecular cells mimicked the mesh-like structure of normal trabecular tissue. In contrast, under an excess of these growth factors, spheroids of high cellularity, resembling the abnormal trabecular tissues of patients with congenital glaucoma, were formed.

Humans↗
PubMed1997

The effects of growth factors on multicellular spheroids formed by chick embryonic retinal cells.

Retinal cells from chick embryos aged 7.5 days of gestation were cultured for two months in a non-adherent suspension culture dish to study the effects of growth factors and co-culture with retinal pigment epithelial cells on their differentiation. Dissociated retinal cells became cellular aggregates (multicellular spheroids) within a day, and rosettes were formed in the spheroids after 2 days. Ultrastructurally, neurons of the rosettes developed connecting cilia, ellipsoids (accumulation of mitochondria), and external limiting membrane, indicative of their differentiation into photoreceptor cells. Epidermal growth factor enhanced the expression of rhodopsin by rosette-forming neurons, while basic fibroblast growth factor induced the growth of Mueller cells at 4 weeks, and their transdifferentiation into lens-epithelial-like cells at 8 weeks. Co-culture of retinal cells with retinal pigment epithelial cells enhanced the formation of rosettes in spheroids. Multicellular spheroids formed in a dish for suspension culture would provide a convenient in vitro system to examine differentiation and transdifferentiation of the retina.

Animals↗
PubMed1997

Aspirin-induced asthma as a risk factor for asthma mortality.

We have recently reported severe airway obstruction and bronchial hyperresponsiveness (BHR) in fatal asthma compared with patients without a history of near-fatal asthma. Based on these findings, we evaluated whether aspirin-induced asthma (AIA) is a risk factor for asthma mortality by analyzing pulmonary function and BHR. FEV1.0% and methacholine inhalation threshold were significantly lower in the fatal asthma group compared with the AIA and non-AIA groups. However, there were no significant differences between the AIA and non-AIA groups. Our results suggested that AIA is not a risk factor for asthma mortality if avoidance of aspirin and aspirin-like drugs is assured.

Adult↗
PubMed1997

Incidence of ocular complications in rheumatoid arthritis and the relation of keratoconjunctivitis sicca with its systemic activity.

To investigate the incidence of ocular complications in patients with rheumatoid arthritis under modern modalities of treatment and find the relationship between its systemic activity and ocular complications, routine ophthalmological examinations were done as a prospective study in 111 consecutive patients including 89 inpatients and 22 outpatients with rheumatoid arthritis seen from April to May 1995, in a hospital with a special clinic for rheumatology. Keratoconjunctivitis sicca (secondary Sjögren's syndrome) was found in 19 patients (17.1%), scleritis in one patient (0.9%), central retinal vein occlusion in 2 patients (1.8%), and idiopathic retinal hemorrhage in 3 patients (2.7%). Patients with keratoconjunctivitis sicca had significantly higher titers of rheumatoid factor (Mann-Whitney's U-test, p = 0.0048), higher levels of IgM (p = 0.0484), and lower levels of HDL-cholesterol (p = 0.0191), compared to patients without it. The incidence of ocular complications was comparable to the previous studies and keratoconjunctivitis sicca should be considered in patients with high titers of rheumatoid factor.

Adult↗
PubMed1997

Effects of 2'-substituents of the first deoxyguanosine residue in the recognition sequence of EcoRI restriction endonuclease activity.

The effects of 2'-substituents of the first deoxyguanosine on EcoRI activity were examined using synthetic octadeoxynucleotides D(GG*AATTCC) containing 2'-substituted derivatives (G*), i.e., 2'-fluoro-2'-deoxyguanosine (dGfl), 2'-chloro-2'-deoxyguanosine (dGcl), and guanosine (rG). The overall structures of the octamers were very similar, as shown by CD and UV measurements, although their EcoRI reactivities were very different: 100% in 60 min for d(GGAATTCC) and d(GGflAATTCC), 5% in 24 h for d[G(rG)AATTCC], and no cleavage at all in 24 h for d(GGclAATTCC). However, the kinetics showed the octamers exhibit similar binding-affinity to the enzyme (10(-6)-10(-7) M). 31P-NMR analysis suggested the modified octamers change the phosphate backbone conformation in a duplex, since an unusual downfield-shifted signal in the spectra was commonly observed for the modified octamers at low temperature (i.e., a duplex state), which was shifted upfield at high temperature (i.e., a single strand state). The order of the differences was dGcl > rG > dGfl-containing octamers, coinciding with that of the vdW volume of 2'-substituents (Cl > OH > F) and the cleavage reactivities. These findings suggest that steric hindrance by the 2'-substituents causes of conformational change of the phosphate backbone close to the scissile bond, and then interferes with the EcoRI reaction.

Binding Sites↗