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Biomedical subjects

K Fukai

Publications and source records attributed to K Fukai.

At least 73 records · Page 4Linked to original sources
PubMed1991

Immunohistochemical localization of type I, III, IV, V, and VI collagens and laminin in neurofibroma and neurofibrosarcoma.

By using antibodies to type I, III, IV, V, and VI collagens and laminin, we examined the localization of interstitial collagens and basement membrane components with indirect immunofluorescence and immunoelectron microscopy (IEM). Furthermore, the morphological changes of these collagens in malignant transformation were investigated. In neurofibroma, IEM showed type I, III, and V collagens to be present diffusely on cross-striated collagen fibrils, whereas type VI collagen was present between the fibrils. Type IV collagen and laminin were observed to surround tumor cells. In neurofibrosarcoma, tumor collagen bundles that reacted with antibodies to type I, III, V, and VI collagens were irregularly arranged. Immunofluorescent deposits that reacted with anti-type IV collagen and anti-laminin antibodies were decreased in number, showing a thin and sparse arrangement.

Collagen↗
PubMed1991

High levels of cholesteryl esters, progesterone and estradiol in the testis of aging male Fischer 344 rats: feminizing Leydig cell tumors.

The levels and fatty acid composition of cholesteryl esters (CEs), and the levels of steroid hormones in the testis of aging Fischer 344 (F344) rats were studied in comparison with those of 6-month-old rats without Leydig cell tumors (controls). The total lipid content in the testis increased as Leydig cell tumors developed: in 23-month-old rats, the content increased to five times higher than that of the controls. The CE level reached about 300 times higher than that of the controls and comprised 57.5% of the total lipid of the testis. The fatty acid composition of the CEs in the tumor compared to the normal tissue from the controls was characterized by a marked increase in 22:4 (n-6) and a decrease in 22:5 (n-6), a characteristic acid in rat testis lipids. Testicular progesterone levels considerably increased with the development of tumors (23-month-old rats, 2870 ng/wet wt; controls, 7 ng/g wet wt). Also, levels of estradiol showed striking increments (23-month-old rats, 2205 pg/g wet wt; controls, 153 pg/g wet wt). On the other hand, testosterone levels decreased (23-month-old rats, 13 ng/g wet wt; controls, 50 ng/g wet wt). These results suggest that Leydig cell tumors in aging F344 rats resemble the ovary tissue of rats in the levels and fatty acid composition of the CEs, and in the levels of steroid hormones. This is supported by the observation that the two kinds of cells found in the tumor tissue resemble cells of the corpus luteum and granulosa cells of the follicles, respectively, in the ovary of rats. In conclusion, the study shows that Leydig cell tumors in aging male F344 rats have a tendency towards feminization.

Aging↗
PubMed1991

Physicochemical and immunological properties of the hepatitis B surface antigen containing the preS2 9 amino acid sequence produced by a recombinant yeast.

The hepatitis B virus surface antigen containing the preS2 nine amino acid sequence produced by a recombinant Saccharomyces cerevisiae (yHBsAg) was purified and its physicochemical properties were determined. Ultrastructurally, the yHBsAg was found to be a homogeneous spherical particle with a diameter of 24 +/- 4 nm. The homogeneity of the yHBsAg particles was also demonstrated by analyses of their buoyant density and isoelectric point. They consisted of protein (53%), lipid (36%) and carbohydrate (11%), and the alpha-helix content was estimated to be 32%, differing from the reported values for human plasma-derived HBsAg (hHBsAg). Immunodiffusion analysis showed that the antigenic specificity of yHBsAg was identical to that of hHBsAg. Immunization of mice demonstrated that the immunogenicity of the yHBsAg was significantly higher than that of hHBsAg.

Amino Acid Sequence↗
PubMed1991

Safety follow-up in a cohort of Biken acellular DPT vaccine recipients in Japan.

In October 1984 in Sweden, a phase II trial of Biken acellular Pertussis vaccine was started and in 1986, a phase III trial of the same vaccine was begun. During the phase III trial, there were three cases of deaths out of 1,385 of study children at two, four and ten weeks after the second dose of the vaccine, due to severe invasive bacterial infections such as H. influenzae, Pneumococcus, or Meningococcus infection. A number of arguments arose about the results of the Phase III trial. No one can either prove or disprove the association between invasive bacterial infection and administration of acellular pertussis vaccine. The purpose of this paper is to discuss the side effects of Biken acellular DPT vaccine. The pediatricians inquired about the physical status of the children who received Biken acellular DPT vaccine. During the observation period, three out of 940 infants suffered from infectious diseases. One suffered from measles, the other from varicella and the last from mumps. Our retrospective study did not reveal any severe invasive bacterial infection cases cases such as the ones experienced in Sweden.

Bacterial Infections↗
PubMed1991

Calculation of efficacy of acellular pertussis vaccine from the number of pertussis patients and vaccinees in three areas.

A study is presented of the efficacy of acellular pertussis vaccine based on the number of pertussis patients and its relationship to vaccination rate in three demographic areas of Osaka Prefecture, Japan. In three separate areas within Osaka Prefecture, the pertussis vaccine is given to children three to six months of age, and in the other two it is given to children two years of age or older. Use of a mathematical method to correct the reported number of pertussis patients per 100,000 population with a constant obtained from analysis of the reported number of exanthem subitum cases allowed us to compare the number of pertussis patients in the three areas with each other. Vaccination rate by age and incidence of pertussis in each city revealed the efficacy of acellular pertussis vaccine to be 94.8%.

Age Factors↗
PubMed1990

Primary cutaneous adenoid cystic carcinoma: ultrastructural study and immunolocalization of types I, III, IV, V collagens and laminin.

A primary adenoid cystic carcinoma of the skin is reported. Light microscopy revealed pseudocysts. PAS-positive basement membrane and true glandular lumen, which in aggregates are specific for adenoid cystic carcinoma. Perineural invasion was also observed. Ultrastructural examinations revealed three types of cystic spaces; pseudocysts, true glandular lumens and intercellular spaces. Enzyme histochemical examinations showed positive reactions for eccrine enzymes, including phosphorylase and succinic dehydrogenase and negative for apocrine enzymes. Immunolocalization of collagens and laminin revealed that basement membranes of the pseudocysts involve Type V collagen as well as Type IV collagen and laminin.

Aged↗
PubMed1990

Rhizobitoxine inhibition of hydrogenase synthesis in free-living Bradyrhizobium japonicum.

Rhizobitoxine produced by Bradyrhizobium species strongly prevented derepression of hydrogenase expression in free-living Bradyrhizobium japonicum, although the toxin had no effect on the activity of cells which had already synthesized hydrogenase protein. Dihydrorhizobitoxine, a structural analog of rhizobitoxine, proved to be a less potent inhibitor of hydrogenase derepression. Rhizobitoxine did not cause cell death at a concentration sufficient to eliminate hydrogenase expression. The large subunit of hydrogenase was not detectable with antibody after derepression in the presence of rhizobitoxine. The general pattern of proteins synthesized from 14C-labeled amino acids during derepression was not significantly different in the presence or absence of rhizobitoxine. These results indicated that rhizobitoxine inhibited hydrogenase synthesis in free-living B. japonicum. Cystathionine and methionine strongly prevented the inhibition of hydrogenase derepression by rhizobitoxine, suggesting that the inhibition involves the level of sulfur-containing amino acids in the cell.

Bacterial Proteins↗
PubMed1990

Possible formation of cutaneous amyloid from degenerative collagen fibers. Ultrastructural collagen changes and the immunoreactivity of cutaneous amyloidosis employing anti-type I, III, IV, V collagen antibodies.

The origins of primary cutaneous amyloid have been investigated and several possibilities are proposed. We investigated here several cases by electron microscopy and found in all cases characteristic filamentous changes which were identical with amyloid structures in the collagen bundles. These observations suggested a possible pathway of cutaneous amyloid formation from degenerative collagen fibers. Further studies were performed using immunoelectron microscopical and immunohistochemical methods employing a panel of anti-collagen antibodies to examine the reactivity of amyloid to them. Our results were much more suggestive of the collagen origin of this kind of amyloid.

Amyloid↗
PubMed1990

[A study of dynamics of orthodontic archwire on the dental arch. 1. Distribution of orthodontic forces during labial movement of bilateral incisors].

The study on labial movement of maxillary unilateral incisor had been reported previously. This study was the case of maxillary bilateral incisors. Orthodontic forces during labial movement of maxillary bilateral incisors which were produced by stainless steel archwire with vertical loops and nickel titanium archwire, were measured and were examined the distribution of orthodontic forces to the dental arch in the experimental apparatus with strain gauges. The following results were found: 1. In nickel titanium archwire, orthodontic forces were distributed to the entire dental arch, and the distribution of orthodontic forces could be classified into three types, which were similar to the previous study. 2. In stainless steel archwire with vertical loops, orthodontic forces were distributed only to bilateral incisors and adjacent tooth to bilateral incisors. 3. When bilateral incisors displaced lingually, it showed that there were additional orthodontic forces distributions as if two unilateral distributions were overlapped. 4. For maxillary bilateral incisors were moved in optimum force, some consideration to adjust the loops of stainless steel archwire was needed.

Dental Stress Analysis↗
PubMed1990

[Cytochemical study of Mg2(+)-ATPase and ALPase activity in human meningiomas].

Ultracytochemical features of microvessels and tumor cells of the human meningiomas were examined by light and electron microscopy with special reference to the distribution of Mg2(+)-ATPase and alkaline phosphatase (ALPase) activity on the walls of the vessels and tumor cell surfaces. Materials used were 4 cases of meningiomas, 2 of which were meningotheliomatous type, one fibroblastic type and one malignant meningioma respectively. For ultracytochemistry, specimens were quickly fixed in an ice-cold 0.1 M cacodylate buffer containing 8% sucrose (pH 7.2) for one hour and transferred to a substrate solution for detection of Mg2(+)-ATPase and ALPase. The preparations were incubated at 37 degrees C for 15-30 min in the medium described by Mayahara et al. for ALPase and for 15-20 min in the medium described by Wachstein and Meisel. The control samples were incubated in a medium containing 1 mM Bromotetramisole for ALPase and also in a substrate free medium for Mg2(+)-ATPase. At the light microscopy, Mg2(+)-ATPase and ALPase activities appeared to be mainly restricted to the capillary wall and around or in the tumor cell nest showing whorl formation. Both enzyme activities were negative in the control study. By electron microscopy, reaction products representing Mg2(+)-ATPase activity were distributed in the basolateral plasma membrane of the endothelial cells on the surface of the pericytes and on the surface of the tumor cells. Reaction products of ALPase activity located mainly on the abluminal surfaces of the endothelial cells and in some specimen on both luminal and abluminal surfaces of those cells. Intense reaction products were distributed evenly on all round surfaces of the tumor cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Detection of dengue 4 virus core protein in the nucleus. I. A monoclonal antibody to dengue 4 virus reacts with the antigen in the nucleus and cytoplasm.

A mouse monoclonal antibody (MAb) to dengue 4 (DEN-4) virus reacted with the antigen in the nucleus as well as in the cytoplasm of DEN-4-infected mammalian and mosquito cells, as demonstrated by the peroxidase-antiperoxidase staining method. The intranuclear antigen appeared to accumulate at the nucleoli, forming spots, whereas the cytoplasmic antigen appeared to be localized mainly in large perinuclear foci in the infected cells. The MAb-reactive antigen was produced in the presence of actinomycin D, which caused the accumulation in the nucleus to be altered to a dispersed pattern. Radioimmunoprecipitation analysis of [35S]methionine-labelled purified virions and Western blot analysis of the antigens prepared from the infected mammalian and mosquito cells showed that the MAb was directed against the DEN-4 virus core protein (Mr 15.5K). These results indicated that the DEN-4 virus core protein was partially transported, soon after its synthesis in the cytoplasm, into the nucleus and accumulated at the nucleoli.

Aedes↗
PubMed1989

The subbasement membrane distribution of type IV collagen in normal human skin.

Samples of normal human skin were obtained from 48 sites in 26 subjects ranging in age from 2 to 85 years. The samples were examined by indirect immunofluorescence and immunoelectron microscopy using anti-human type IV collagen antibodies produced by immunizing rabbits with type IV collagen extracted from human placenta. Fluorescence was observed as granular or fine fibrous patterns, not only in the basement membrane at the dermo-epidermal junction, around the vessels, and the accessory organs of the skin, but also in the dermal regions in the vicinity of the basement membranes. This suggests the presence of type IV collagen in the dermis deep to the basement membrane. Ultrastructurally, the extrabasal lamina distribution of type IV collagen was noted as a partial distribution around the fibroblasts that existed close to the basal lamina. These findings are considered to be important in examining the function of this collagen in the dermis and the dynamics and metabolism of the basement membrane under normal and abnormal conditions.

Adolescent↗
PubMed1989

Farber's lipogranulomatosis in siblings: light and electron microscopic studies.

Two cases of Farber's lipogranulomatosis in siblings are reported. The clinical features included contractures of the limbs with swelling of the joints and subcutaneous nodules and erythematous infiltrated plaques. On histology there were many large foam cells in the dermis, and electron microscopy showed numerous large cells with round cytoplasmic lamellar and microtubular bodies.

Child, Preschool↗
PubMed1989

[Case report of periodontal disease with periodic neutropenia].

A case of periodic neutropenia with specific symptoms of gingiva and alveolar bone loss in primary dentition is reported. The patient was a boy, and it was followed between the ages of 3- and 9 years-old. At the period of neutropenia he was suffered from recurrent redness, swelling and bleeding of the gingiva, and also with cold-like symptoms with fever. Although the cause of these symptoms was not definite at first, even in medical exploration, we could diagnose this disease as periodic neutropenia by the process of dental therapy. By alveolar bone resorption, pocket formation and severe tooth mobility, the patient had lost more than half of his primary teeth at the end of 2 years after the initial examination. However throughout this period we motivated and instructed the patient and his mother how to brush his teeth. His oral hygiene was improved in the mixed and permanent dentition stages. Then there was no evidence of bone resorption around the teeth of the permanent dentition stage, but recurrent gingival symptoms are continuing now. The specific feature of this case is found in the gingival findings. There was no ulceration of the oral mucosa, but a bright red jelly-like appearance was found periodically in the area of the marginal and attached gingiva. The junction between the reddened attached gingiva and the alveolar mucosa was well-defined. The serial examination of peripheral blood in this case revealed the cycle of neutropenia as 16 to 21 days. During this examination, and at the almost time of neutropenia of this patient, hyperplasia of monocytes and lymphocytes occurred. In this situation there was no clinical signs except for gingival redness. However at other times, generally marked signs were recurrent. This may have occurred due to the lack of both neutrophils and monocytes. From the above results we think that periodic neutropenia may be diagnosed first in the dental clinic by the distinctive redness in the gingival area as one specific sign of this disease. We also think that plaque control procedures may retain the teeth.

Alveolar Bone Loss↗
PubMed1989

[Establishment of clinically healthy gingiva in Macaca irus].

UNLABELLED: The purpose of this study was to assess the methods of establishing of clinically (experimental) healthy gingiva and to evaluate the status of healthy gingiva in Macaca irus. Three monkeys (2 males and 1 female) were used. After preliminary feeding with hard food for 6 months, plaque control procedures (scrubbing method, modified Stillman method, and flossing) were started. Frequency of plaque removal was three times per week under KETALAR (SANKYO, Co. Tokyo), dissociative anesthesia. We also monitored clinical data. RESULTS: 1. Forty-nine days later, clinically healthy gingiva were achieved. During this period, no side effects and no tolerance occurred using 12.5 mg/kg of KETALAR, and effective time to perform the procedure was 21.8 minutes. 2. Depending on the plaque control procedure, plaque index (P11), gingival index (GI), and probing depth (PD) were reduced (especially in the first week). However, the level of marginal gingiva (LMG) did not change. 3. Initially and throughout the experiment, PII, GI, PD were lower value in lower jaws, but by the end of experiment there were no differences between the two jaws in PII and PD. However, GI was still lower in the lower jaw at this time. There were no differences between the data for the right and left sides of the jaws at any time throughout the experiment. 4. At the end of experiment, the clinically (experimental) healthy gingiva yielded the following data: PII, 1.7 +/- 0.61; GI, 0.1 +/- 0.60; PD, 1.3 +/- 0.53. No individual differences were found in any of the monkeys at the end of experiment.

Animals↗
PubMed1989

Acquired pigmented macules in human piebald lesions. Ultrastructure of melanocytes in hypomelanotic skin.

Two cases of piebaldism are reported. The first patient was a 9-month-old girl with inborn hypopigmented areas on the frontal region of the scalp and both knees. There were no melanocytes in the lesions. In the second case, we observed the patient from 2 months of age for a period of 9 years. Many hyperpigmented spots appeared on the hypomelanotic areas on the frontal region of the scalp, abdomen and both knees. Electron-microscopic examinations of the hypomelanotic skin disclosed an area with regularly distributed melanocytes as well as an area with no melanocytes. Most of the melanosomes were ellipsoidal and lamellar. They were in stage II to III, which signified delayed pigmentation. Hyperpigmented spots were slightly enlarged following PUVA treatment.

Female↗