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Biomedical subjects

K Fujiki

Publications and source records attributed to K Fujiki.

At least 91 records · Page 5Linked to original sources
PubMed1992

Examination of bacterial characteristics of anaerobic membrane bioreactors in three pilot-scale plants for treating low-strength wastewater by application of the colony-forming-curve analysis method.

Characteristic sludge ecosystems arising in anaerobic membrane bioreactors of three pilot-scale plants treating low-strength (less than 1 g of biological oxygen demand per liter) sewage or soybean-processing wastewater were examined by analysis of the colony-forming-curves (CFC) obtained by counting colonies at suitable intervals. The wastewaters, containing high amounts of suspended solids (SS) (SS/chemical oxygen demand ratio, 0.51 to 0.80), were treated by using two types of bioreactors: (i) a hydrolyzation reactor for solubilization and acidification of SS in wastewater and (ii) a methane fermentation reactor for producing methane. The colony counts for the two sewage treatment plants continued to increase even after 3 weeks of incubation, whereas those for soybean-processing wastewater reached an approximately constant level within 3 weeks of incubation. The CFCs were analyzed by correlating the rate of colony appearance on roll tubes with the physiological types of bacteria present in the bioreactors. It was found that there were large numbers of slow-colony-forming anaerobic bacteria within the bioreactors and that the viable populations consisted of a few groups with different growth rates. It is considered that the slow-growing colonies appearing after 10 days of incubation were the dominant microflora in the sewage treated by hydrolyzation reactors. In particular, highly concentrated sludge (30.0 g of mixed-liquor volatile SS per liter) retained by the membrane separation module contained a large number of such bacteria. Slow-growing colonies of these bacteria could be counted by using a sludge extract medium prepared from only the supernatant of autoclaved sludge. In addition, the highest colony counts were almost always obtained with the sludge extract medium, meaning that most of the anaerobic bacteria in these sludges have complex nutrient requirements for growth. This report also indicates the usefulness of application of the CFC analysis method to the study of bacterial populations of anaerobic treatment systems.

Journal Article↗
PubMed1992

[An epidemiogenetic study of typical retinitis pigmentosa in Japan--a preliminary report of nationwide, multicenter study].

We performed a nationwide, multicenter study of typical retinitis pigmentosa with reference to the inheritance patterns of the disease. A total of 253 probands were registered during two months of 1989, and an analysis of the parental consanguinity of 182 probands with the method of inbreeding coefficient enabled us to estimate the relative prevalence of genetic types; autosomal recessive trait: 47.6%; autosomal dominant trait: 17.3%; sporadic cases: 34.6%. A comparison of the results with previous studies has indicated a decrease in the prevalence of the autosomal recessive trait and an increase in the sporadic cases, as would be expected from the decrease in consanguineous marriages and offsprings in the past few decades in Japan. X-linked retinitis pigmentosa was rarely identified, but precise evaluation of its frequency needs further investigation.

Adolescent↗
PubMed1992

[The empirical risk of retinitis pigmentosa in Japan].

The empirical risk of hereditary retinitis pigmentosa (RP), was studied based on a survey of the data from 378 families with RP who were seen in Juntendo University hospital from 1980 to 1988. If the cases have had affected sibling, the empirical risk is 19% for the other siblings, and 29% if they have parental consanguinity. Moreover the risk for male siblings is about 1.7 times higher than for female siblings. The prevalence in the general population of carriers with autosomal recessive hereditary RP was calculated to be about 0.8 to 1.7 in 100 persons. If a hereditary RP case marries a normal and unrelated partner, the risk is 0.4-0.9% for their child. If a case has many affected relatives (parents, grandparents, uncles or aunt etc), the risk is 24% for a son, and 30% for a daughter. Some normal persons among autosomal dominant families with incomplete penetrance are suspected to be carriers. The rate of penetration of the autosomal dominant gene was estimated to be 0.54. Therefore, the risk is 8.6% for the children of such persons. If the carriers are among X-linked families, the risk is 36% for their son. The risk is 1% or more for children of sporadic cases.

Adolescent↗
PubMed1992

[Molecular biological study of the rhodopsin gene in Japanese patients with autosomal dominant retinitis pigmentosa].

The author analyzed codon 347 of the rhodopsin gene using PCR (polymerase chain reaction) amplification and restriction enzymes in 19 unrelated Japanese families including 28 patients with autosomal dominant retinitis pigmentosa (ADRP). An allele of codon 347 mutation was found in a family (father and daughter). Sequence analysis shows that the mutation is from CCG to CTG. This mutation appears to be the cause of one form of ADRP, since it was also found in Japanese cases of ADRP which have a different racial background from families reported by Dryja et al.

Codon↗
PubMed1992

High frequency of mitochondrial ND4 gene mutation in Japanese pedigrees with Leber hereditary optic neuropathy.

The association of the ND4 gene mutation (mutation) at nucleotide position 11778 of mitochondrial DNA (mtDNA) was investigated in 14 definitive Japanese pedigrees with Leber hereditary optic neuropathy (LHON). The mutation was detected by SfaNI and MaeIII restriction fragment length polymorphisms of mtDNA amplified by polymerase chain reaction. All 14 LHON pedigrees exhibited the mutation, whereas 10 controls did not. The association of this mutation with LHON was revealed to be significantly higher in Japanese (91.7%) than in 27 reported Caucasian (51.9%) LHON pedigrees, implying genetic heterogeneity. In the tested 14 pedigrees, 28 cases with the mutation comprised 19 affected (17 male and 2 female) and 9 asymptomatic (all female except for one) individuals. Such a predominance of males in the incidence of LHON suggested probable participation of additional pathogenetic factor(s) in the development of optic atrophy in LHON patients.

Adolescent↗
PubMed1992

Clinical features of Japanese family with autosomal dominant retinitis pigmentosa caused by point mutation in codon 347 of rhodopsin gene.

Four members in a Japanese family had autosomal dominant retinitis pigmentosa caused by a single point mutation in codon 347 of the rhodopsin gene. The youngest, an 11-year-old girl, had an abnormal electroretinographic response, although her fundus appeared normal. The other affected family members noticed night blindness in the second decade. Their fundi showed diffuse pigmentation with concentric visual field loss, and there was no recordable electroretinographic response. Cataract developed in the fourth decade in the older patients. Good visual acuity was retained however, even in the fifth decade, after cataract extraction. These clinical features were similar to those of American patients (European family origin) with the same mutation of the rhodopsin gene reported previously.

Adult↗
PubMed1991

A mutation of mitochondrial DNA in Japanese families with Leber's hereditary optic neuropathy.

Leber's hereditary optic neuropathy (LHON) is a maternally inherited disease characterized by optic nerve degeneration associated with severe bilateral visual loss in young men and occasionally in women. A mitochondrial DNA (mtDNA) replacement mutation in LHON patient, G to A transition at nucleotide position (nt) 11778 converting the 340th arginine to histidine in the NADH dehydrogenase subunit 4, was detected as SfaNI site polymorphism (Wallace et al., Science, 242: 1427-1430, 1988). To evaluate if the SfaNI site loss can be used to diagnose LHON patients, mtDNAs from peripheral blood of six affected males including five probands from five unrelated Japanese families with LHON, a pair of parents and a normal sister of one of the probands and 4 control persons were analyzed using PCR amplification method. The mutation of leukocyte mtDNA at nt 11778 was identified in all of the affected patients, the normal mother and the sister examined, while the father who is normal and 4 control persons did not show the change. These findings support that the mutation at nt 11778 is also associated with LHON in the Japanese and the test of the SfaNI site loss described here is useful for confirming the clinical diagnosis of LHON patients with the mutation at nt 11778.

Asian People↗
PubMed1991

A high frequency of detection of Helicobacter pylori in whitish exudate of gastric ulcer.

Helicobacter pylori has been implicated in the pathogenesis of chronic gastritis and peptic ulcer. However, no report to date has been made on the presence of H. pylori in the whitish exudate of peptic ulcers. We examined the biopsy specimens of 52 patients (42 men and 10 women, aged 29-78, not taking steroids or nonsteroid antiinflammatory drugs), and evaluated the frequency of detecting the organism in the whitish exudate of gastric ulcers in comparison with that in the ulcer border, gastric fundic gland, and pyloric gland using microaerobic culture and acridine-orange stain. H. pylori was detected in high rates: 38 (73%) of 52 cases by culture, and 50 cases (96%) by staining of the whitish exudate, 42 (81%) of 52 cases by culture, and 46 cases (88%) by staining of the ulcer border. The frequency for the other regions were 81% by culture and 90% by staining of the fundic gland, and 81 and 90% of the pyloric gland, respectively. Of all sites studied by the staining method, H. pylori was detected at the highest frequency in the whitish exudate. The fact that many H. pylori live in the whitish exudate of gastric ulcer, suggests a causal relationship between H. pylori and gastric ulcer.

Acridine Orange↗
PubMed1991

[A trial of molecular diagnosis in Leber's optic neuropathy].

The high frequency of mitochondrial DNA mutation at the nucleotide position (nt) 11,778 was reported in cases of Leber's hereditary optic neuropathy (LHON) after the first report by Wallace et al.. We already reported that it provided a simple diagnostic test by means of PCR (polymerase chain determined the diagnosis of LHON in a case. No nt 11,778 mutation was found in patients with the other optic nerve diseases and in normal controls. This shows the usefulness of molecular diagnosis in LHON. Problems of genetic counselling for patients and female carriers and the possibilities to clarify the cause of LHON were discussed.

DNA↗
PubMed1989

Is risk to motor neuron disease influenced by the season of birth?

Months of the birth in 310 cases with motor neuron disease were compared with 244 of their spouses who were used as the controls. Cases were born more often in the spring to summer months and less in the winter months. Birth factors should be carefully evaluated in this disease.

Birth Intervals↗
PubMed1989

[Statistical analysis of Marfan's syndrome].

To evaluate the ocular complications of Marfan's syndrome which cause severe visual disturbance, we retrospectively investigated 104 patients (208 eyes) with Marfan's syndrome. Dislocation of the lens, the most frequent ocular manifestation, was detected in 151 eyes (72.6%). There were 33 eyes with a visual acuity 0.1 or less. In this group, we found retinal detachment in 12 eyes (36.4%) and glaucoma in 5 eyes (15.2%) as the causes of visual disturbance. Among 17 eyes with retinal detachment, 5 eyes (29.4%) had horizontally dislocated lens. On the other hand. The lens dislocation in a downward direction was found in 5 (22.7%) of 22 eyes with glaucoma. No lens dislocation in an upward direction was found in eyes with glaucoma. The incidence of retinal detachment in aphakic eyes (5/31, 16.1%) was higher than that in the phakic group (16/177, 9.0%). In only 2 (3.6%) of 56 eyes, did the lens dislocation become markedly worse during the observation period. From these data, we re-confirmed that retinal detachment and glaucoma are the most important ocular complications of Marfan's syndrome leading to severe visual disturbance. The decision to operate on the dislocated lens should be made cautiously.

Adolescent↗
PubMed1987

Genetic epidemiology of Duchenne muscular dystrophy in Japan: classical segregation analysis.

Classical segregation analysis was performed on 651 male probands in 597 families with Duchenne muscular dystrophy (DMD) collected from 20 of 25 National Institutions for Muscle Diseases in Japan. The proportion of sporadic cases is compatible with 1/3 expected for an X-linked lethal trait with an equal mutation rate in egg and sperm, the estimated mutation rates being 9.2 X 10(-5) and 10.9 X 10(-5)/gamete/generation, respectively. The incidence and prevalence among males were estimated to be 29.2 X 10(-5) and 6.7 X 10(-5), respectively. These results indicated no difference from the patterns of DMD in Western countries.

Gene Frequency↗
PubMed1987

Activity of red cell esterase D in 50 cases of retinoblastoma patients and their family members.

Esterase D was qualitatively and quantitatively analyzed in the red blood cells from 50 retinoblastoma patients who had been followed-up at Juntendo University and their family. In only one case with deletion of chromosome No. 13 (q12.3-q21.2), was the esterase D activity (type 2) 1.47 Unit/gHb which was approximately 50% of the level in normals. Additional retinoblastoma patients and their family members, 77 parents and 25 siblings, showed a normal range of esterase D level in their own phenotypes. These facts confirmed that the deletion of an esterase D locus was infrequent (approximately 2% in our series) in retinoblastoma patients. It was also compatible with the published data that the range of deletion of chromosome was No. 13 (q12.3-q21.2) involving 13q14.

Carboxylesterase↗