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H Sasahara

Publications and source records attributed to H Sasahara.

At least 19 recordsLinked to original sources
PubMed1998

Effect of preinduction of heat-shock proteins on acetic acid-induced small intestinal lesions in rats.

Bowel dysfunction such as irritable bowel syndrome caused by stress is well described. Previous reports suggest that stress is known to cause the release of endogenous substances such as catecholamine, beta-endorphine, 5-hydroxytryptamine, corticotropin-releasing factor, and thyrotropin-releasing hormone (TRH). However, the role played by these neurohormonal mediators in bowel dysfunction under stress conditions is not well known. We investigated the influence of water-immersion stress or TRH administration on the expression of 60-kDa, 72-kDa, and 90-kDa heat-shock proteins (HSP60, HSP72, and HSP90, respectively) in rat small intestinal mucosa by Western blot and immunohistochemical analyses. The cytoprotective function of preinduced HSPs on experimentally induced mucosal damage also was studied. In order to investigate the influence of preinduction of HSP60 on small intestinal damage, the small intestinal lumen was perfused with 1.5% acetic acid 1 ml/min for 15 min with or without pretreatment with water-immersion stress or TRH administration. Expression of HSP60 was significantly increased by water-immersion stress or TRH administration in the small intestinal mucosa, whereas HSP72 and HSP90 did not increase. Interestingly, expression of this protein showed the biphasic peak pattern after water-immersion stress or TRH administration. Each peak was observed 3-6 hr and 21-24 hr after the initiation of water-immersion stress or TRH administration. Immunohistochemical study also showed a significant increment of HSP60 in both the cytoplasm and nuclei of the small intestinal mucosal cells. No histopathologic alteration was observed in rat small intestinal mucosa after each treatment. Small intestinal damage caused by 1.5% acetic acid perfusion was not influenced by preinduction of HSP60. We demonstrated that water-immersion stress or TRH administration specifically induced HSP60, although preinduction of this protein did not show a cytoprotective function in the small intestinal mucosa.

Acetic Acid↗
PubMed1998

Relationship between mothers' gingival condition and caries experience of their 3-year-old children.

OBJECTIVES: The main aim of this study was to investigate the relationship between mothers' gingival condition (an assumed indicator of their self-care level) and the prevalence and severity of dental caries of their children. SAMPLE AND METHODS: Subjects comprised 1471 pairs of mothers and their children who attended for the 3-year-old dental check-up at a community health centre in Hiroshima. The mothers' gingival condition was scored as 'excellent (+2)', 'good (+1)', 'questionable (0)', 'poor (-1)' or 'very poor (-2)' according to the criteria of the Oral Rating Index (ORI). Caries experience of the children was recorded using the WHO caries diagnostic criteria for dmft. RESULTS: The percentage of caries-free children was 51.3%, and the mean dmft score was 2.61. The percentages of caries-free were higher and the mean dmft level were lower in the children of mothers with better gingival condition compared to the children of mothers with worse gingival condition. CONCLUSIONS: Mothers' gingival condition was associated with the prevalence and severity of dental caries of their children.

Adult↗
PubMed1997

Effect of pre-induction of heat shock proteins on indomethacin-induced small-intestinal lesion in rats.

Systemic hyperthermia induces the synthesis of heat shock proteins (HSPs) in several organs. However, the mechanism of induction and the functions of HSPs in the small-intestinal mucosa have not been established. We examined the expression of HSPs in the small-intestinal mucosa after systemic hyperthermia, and evaluated the cytoprotective function of pre-induced HSPs on experimentally induced mucosal damage. HSP expression was investigated by Western blot and densitometric analysis before and after hyperthermia (42.5 degrees C; 20 min). Expression of a 72-kDa heat shock protein (HSP72) and a 73-kDa heat shock protein (HSP73), both of which are endogenous cytoprotectants in vitro significantly increased, peaking 6-9 h after hyperthermia, without any pathologic alterations, whereas the expression of a 60-kDa heat shock protein (HSP60) did not increase. To investigate the influence of pre-induction of HSPs on small-intestinal damage, rats received indomethacin (10 mg/kg; orally) with or without pre-treatment with hyperthermia. Small-intestinal damage caused by indomethacin was not influenced by pre-induction of HSP72 and HSP73. We demonstrated that systemic hyperthermia induced HSP72 and HSP73, although pre-induction of these proteins did not have a cytoprotective function in the small-intestinal damage caused by indomethacin.

Animals↗
PubMed1997

Effect of preinduction of heat shock proteins on acetic acid-induced colitis in rats.

In order to study the cytoprotective function of heat shock proteins (HSPs) in vivo, the effect of preinduction of HSPs by hyperthermia on acetic acid-induced colitis was investigated. Expression of 60-kDa, 72-kDa, and 90-kDa heat shock proteins (HSP60, HSP72, and HSP90, respectively) in rat colonic mucosa was investigated by Western blot analysis and immunohistochemical study before and after hyperthermia. Following pretreatment with or without hyperthermia, the rats received intrarectal infusion of various doses of acetic acid. The colonic mucosal damage was evaluated by macroscopic and microscopic assessments 24 hr after the intrarectal infusion of acetic acid. Expression of HSPs was significantly increased by hyperthermia in rat colonic mucosa. Immunohistochemical study also showed the increments of HSPs in the colonic mucosal cells after hyperthermia. Acetic acid-induced colitis was dramatically prevented by pretreatment with hyperthermia when HSP72 and HSP90 were preinduced. On the other hand, induction of HSP60 did not correlate with mucosal protection. Our findings suggest that HSP72 and HSP90 may have cytoprotective function against acetic acid-induced mucosal damage. These results may be important for understanding the mechanism of "adaptive cytoprotection" mediated by HSPs.

Acetic Acid↗
PubMed1997

Differential induction of HSP60 and HSP72 by different stress situations in rats. Correlation with cerulein-induced pancreatitis.

We previously reported that water-immersion stress specifically induced the synthesis of a 60-kDa heat-shock protein (HSP60, chaperonin homolog) in pancreatic cells and preinduction of HSP60 completely prevented development of cerulein-induced pancreatitis in the rat in an HSP60 quantitatively dependent manner. In order to study the cytoprotective function of a 72-kDa heat-shock protein (HSP72, stress-inducible hsp70), the effect of specific preinduction of HSP72 by hyperthermia on cerulein-induced pancreatitis was investigated and compared with the effect of preinduction of HSP60 in this study. Expression of HSP60 and HSP72 in the pancreas was investigated by immunoblot before and after water immersion or hyperthermia. Following pretreatment with water-immersion stress or hyperthermia, the rats were injected with cerulein (40 micrograms/kg, intraperitoneally). The pancreas wet weight and serum amylase concentration were measured before and after cerulein injection. Hyperthermia (42.5 degrees C, 20 min) specifically induced HSP72 in the pancreas. The synthesis of HSP60 was specifically induced by water-immersion stress in the pancreas. Cerulein-induced pancreatitis was clearly prevented by specific preinduction of HSP60 by water-immersion stress. However, preinduction of HSP72 by hyperthermia had no preventive effect on cerulein-induced pancreatitis. Our findings suggest that HSP60 and HSP72 have distinct functions in the pancreas, and their induction mechanisms are also different in vivo. These results could be important for understanding the mechanism of "adaptive cytoprotection" in the pancreas mediated by heat-shock proteins.

Amylases↗
PubMed1997

Induction of a 72-kDa heat shock protein and cytoprotection against thioacetamide-induced liver injury in rats.

Heat shock proteins are ubiquitous intracellular proteins induced by various physiological stress-related events. A 72-kDa heat shock protein (HSP72) has been reported to be an endogenous cytoprotectant in variety of cells in vitro. In order to study the cytoprotective function of HSP72 in the liver, the effect of preinduction of HSP72 in rat liver by systemic hyperthermia on thioacetamide-induced hepatic injury was investigated in this study. Expression of HSP72 in the liver was investigated by immunoblot and densitometric analysis. Rats were injected with thioacetamide (100 mg/kg, subcutaneously) with or without preinduction of HSP72 by hyperthermia. Serum AST and ALT concentrations were measured before and after thioacetamide injection in both group. Histologic alteration of the liver was evaluated also. Systemic hyperthermia (42.5 degrees C, 20 min) significantly induced HSP72 in the liver. Thioacetamide-induced hepatic injury was clearly prevented by preinduction of HSP72 by hyperthermia. Prevention of hepatocyte damage was more clear in the area around central veins where HSP72 induction was apparent. Our findings might suggest that HSP72 has an important function in the liver with respect to cytoprotection. These results might be important for understanding the mechanism of "adaptive cytoprotection" in the liver mediated by the function of heat shock proteins as "molecular chaperons" as reported in vitro.

Alanine Transaminase↗
PubMed1997

Disseminated intra-abdominal cystic lymphangiomatosis with severe intestinal bleeding. A case report.

We describe cystic lymphangiomatosis with intestinal bleeding developing multiple lymphangiomas in the small intestine, mesentery, mesocolon, omentum, retroperitoneum, and spleen. Small intestinal fluorography showed multiple polypoid lesions, mainly in the jejunum. Ultrasonography, computed tomography, and magnetic resonance imaging showed diffuse cystic tumors in the mesentery and spleen. Cystic lymphangiomatosis was proved by histologic findings of the biopsied specimen at laparotomy.

Abdominal Neoplasms↗
PubMed1997

Development of an oral health indicator in infants.

OBJECTIVE: To develop a simple predictive indicator for 1.5-year-old infants' oral health as an aid for maternal preventive efforts. DESIGN: The development of an indicator was based on the relationship between life style factors of the 1.5-year-old infants and the caries incidence of the same children at three years of age. Data gained at examination of the 3-year-old subjects were subjected to analysis with the caries-free information on the same subjects at 1.5 years. SETTING: A community health centre in Hiroshima Japan. SUBJECTS: 1575 children received an oral check-up at 3 years of age at a community health centre. OUTCOME MEASURES: The category scores of the six items which were extracted retrospectively from life style factors at 1.5 years affecting caries prevalence at 3 years of age were quantified and transformed into integral numbers so as to make up a total of 100. The sum of the six transformed scores was named an Infants Dental Index (IDI). RESULTS: The IDI score was associated significantly with the dmft score at 3 years of age (r = -0.18 P < 0.001). When the subjects were classified into four groups with respect to the IDI score these four groups were significantly related to the caries onset between 1.5 and 3 years of age (chi 2 = 36.74, P < 0.001 CONCLUSIONS: The IDI developed in this study appeared to be valid so that it could be applied in the field of the community dental health to identity higher risk infants and direct more effective health education to mothers.

Algorithms↗
PubMed1996

A pylorus-retaining pancreatic head-duodenectomy for cancers of the duodenal papilla and the lower bile duct.

With the development of diagnostic technology, the surgical methods of cancer therapy have been expanded, and operations have been performed using a procedure corresponding to the stage of cancer to improve the postoperative QOL. A 79-year-old man with cancer of the duodenal papilla and obstructive jaundice, and a 63-year-old woman with cholangiocarcinoma in the lower region complicated by cholangitis caused by Candida underwent resections of the pancreatic head and duodenum, and pancreaticogastrostomies retaining the pylorus. Satisfactory results were obtained in both cases. The merits of the procedure were that there were few complaints, sufficient food could be ingested and the QCL was maintained. The benefits of pancreaticogastrostomy are that the anastomosis procedure is simple, the gastric wall is thicker than the jejunum and blood flow is plentiful. The dorsal gastric wall is located close to the pancreatic cut-end, therefore tension is not created, and the pancreatic enzymes are not activated because the anastomosis site does not contact the intestinal fluid. These characteristics should decrease the rate of anastomosis failure which can be a fetal complication. A safer operation is desirable, particularly for elderly patients or patients who have complications.

Aged↗
PubMed1994

Alteration of femoral structure in later life by chronically feeding caffeine during rapid growing period in newborn female rats.

The effects of caffeine intake in early life on bone structure later in life were studied in rats. At day 9 of gestation, dams were divided into 2 groups. Group 1 (control) received a 20% protein diet; group 2 received the 20% protein diet supplemented with caffeine (2 mg/100 g body weight). After birth pups were continuously fed their respective diets until day 93, when the diet of group 2 was replaced with a noncaffeine 20% protein diet. On day 388 animals from both groups were weighed, killed, and femora and mandibles were removed. Calcium, phosphorus, magnesium, zinc, hydroxyproline, and hexosamine concentrations were measured. Radiographs of some femora were taken and paraffin cross sections were made at the midshaft of others. Femora in the caffeine group were wider, periosteal bone area/total bone area was greater, the cross sectional area of femoral bone was smaller, and there were fewer osteocytes/bone area than in controls. Calcium, phosphorus, zinc, and hydroxyproline concentrations in the caffeine group were less in both bones of the caffeine group. These results indicate that if animals are exposed to caffeine during the rapidly growing period, changes occur in femoral bone which are similar to those that occur with aging.

Animals↗
PubMed1993

Relationship between CPITN and oral health behaviour in Japanese adults.

Many studies on toothbrushing have concentrated on clinically diagnosing plaque and measuring periodontal status as indicators of oral health behaviour. From a behavioural point of view, however, the more important objective is the health behaviour itself. To investigate the relationship of oral health behaviour to periodontal status, 517 urban employees in Japan (249 men and 268 women aged 20-59 years) responded to a 20-item dental health behaviour questionnaire, entitled the HU-DBI, and had their periodontal conditions examined using the CPITN. Only 1 per cent were found with a healthy periodontium (Code 0), and 9 per cent had bleeding on probing (Code 1). Calculus (Code 2) was the most prevalent condition with 51 per cent of subjects having this code as the worst condition, followed by shallow pockets (Code 3) in 30 per cent, and deep pockets (Code 4) in 9 per cent of the sample. The mean HU-DBI score was 4.2 (out of 12). Females had somewhat higher scores than males (4.4 vs. 4.0, p < 0.05). CPITN had a negative relationship with the HU-DBI (r = -0.26, p < 0.001), and a positive relationship with age (r = 0.40, p < 0.001). Similar relationships were observed in each gender. These data demonstrate the relationship of age with periodontal status, and periodontal status with oral health behaviour. A two-dimensional matrix of HU-DBI score by CPITN may provide a simple and effective means of identifying low and high risk individuals.

Adult↗
PubMed1992

Role of Porphyromonas gingivalis 40-kDa outer membrane protein in the aggregation of P. gingivalis vesicles and Actinomyces viscosus.

Porphyromonas gingivalis, an important pathogen in periodontitis, produces extracellular vesicles that aggregate with Actinomyces viscosus cells. A 40-kDa outer membrane protein (OMP)-coding gene from P. gingivalis was cloned and the protein was found to be localized in these vesicles. The recombinant 40-kDa OMP did not show aggregation activity. However, affinity-purified antibody against the recombinant protein significantly inhibited aggregation of P. gingivalis vesicles with A. viscosus cells. The antibody also inhibited cellular coaggregation of several strains of P. gingivalis with A. viscosus cells, but not with other periodontal pathogens. Moreover, aggregation of A. viscosus cells with P. gingivalis vesicles was inhibited in a dose-dependent manner by pre-treatment of the A. viscosus cells with the recombinant protein. These findings suggest that the 40-kDa OMP may be an important aggregation factor of P. gingivalis.

Actinomyces viscosus↗
PubMed1992

Gene cloning of Porphyromonas gingivalis specific antigens recognized by serum of adult periodontitis patient.

1. Porphyromonas gingivalis is believed an important pathogen of adult periodontitis. A gene library of P. gingivalis 381 was constructed in lambda phage vector L47.1. The library was probed with serum obtained from patients of severe adult periodontitis. Two clones, lambda MDBG101 and lambda MDBG103 which were expressed, 200 and 160 kDa respectively, were selected and further studied. 2. The expressed antigens in these two clones were also reacted with rabbit antiserum against whole cells, capsular fraction and cell surface fraction of P. gingivalis. 3. Genes coding protein antigens in lambda MDBG101 and lambda MDBG103 were subcloned into high-copy-number plasmid vector pACYC184 and subclones obtained were designated as MD101 and MD103. Recombinant plasmids, pMD101 and pMD103, differed in their restriction endonuclease digestion. 4. Immunodiffusion analysis showed that cloned proteins from MD101 and MD103 reacted with antiserum against P. gingivalis but did not react with antiserum against Prevotella intermedia, Prevotella loescheii and Prevotella asaccharolyticus. 5. These data suggest that P. gingivalis species-specific antigens has been successfully cloned and expressed in Escherichia coli. Since these cloned specific antigens were recognized by adult periodontitis patient sera, the recombinant antigen will be useful material for the development of serodiagnosis of P. gingivalis infection in adults periodontitis.

Adult↗
PubMed1990

Effects of maternal caffeine with zinc intake during gestation and lactation on bone development in newborn rats.

On day 9 of gestation, pregnant dams were randomly divided into 3 groups. Dams of group 1 were fed a 20% protein diet as a control. Dams of group 2 were fed a 20% protein diet supplemented with caffeine. Dams of group 3 were fed a 20% protein diet supplemented with caffeine and zinc. The amount of caffeine added to the maternal diet was 2 mg/100 g body weight; the amount of zinc was 0.6 g/kg of diet. At birth, pups were mixed within each group, and 8 randomly selected pups from each group were assigned to each dam of the respective group and were continuously fed the same diet. On day 15, the pups were killed and cranial bones, mandibles and femurs removed. The bones were measured, and the mineral content of the mandibles and femurs was determined. Although there were no differences in the dimensions of the cranial bones among the groups, the measurements and mineral content of the mandibles and femurs were consistently affected by the caffeine in the diet. On the other hand, supplementation of the caffeine-added diets with zinc led to greatly improved bone development, reaching values up to or beyond control levels. Thus zinc supplementation of a caffeine diet given to the dams during gestation and lactation can favourably influence the otherwise impaired bone development of their offspring.

Animals↗
PubMed1988

Comparison of objective methods for determining ventilatory threshold.

This study was undertaken to compare and re-examine the relation of lactate threshold (LT) and ventilatory threshold (VT), using six objective determination methods proposed previously. Twenty-one young male subjects performed a cycle exercise test in which the work rate was increased by 150 kg.m every 2 min up to his limit of volitional fatigue. Through each test, gas exchange parameter measurements were made every 1 min (every 30 s at nearly maximal level), and the venous blood samples were taken from a warmed ear lobe at each work rate for determining blood lactate concentration. LT and its variance were determined by the intersecting straight lines regression. LT ranged from 0.72 to 1.40 l/min in terms of VO2, and the mean value of S.D. for each LT was about 0.1 l/min. Each objective method for determining VT used in this study was based on the simple modelling of the criterion for visual detection of VT, that is the non-linear increase in VE or the systematic increase in VE/VO2. When the relationship between LT and VT was examined, VT by the objective methods based on determining minimum value of VE/VO2 showed relatively high consistency with LT. Of 16-20 individuals out of all 21 subjects, there were VT within LT +/- 0.2 in VO2. It is concluded that VE/VO2 is a more sensitive index for detecting VT than VE in the gas exchange parameters, and the objective VT determination method based on minimum value of VE/VO2 could facilitate estimation of LT within an error of +/- 0.2 l/min VO2 in most normal individuals.

Adult↗
PubMed1988

[Behavioral dental science. Part VIII. The dentist's rating and adolescents' perceptions of oral health].

The purpose of this study was twofold. The first objective was to measure the periodontal status and perceptions of oral health in adolescents. The second objective was to determine the effects that a program of dental health education would have on their periodontal status and perceptions of oral health. The dental health education with a 90-minute lecture had been given to eleventh-grade students (352) in the previous year. The dental health education program was not carried out in tenth-grade students (442) yet. The oral examination was performed by a dentist for both grades. The examination time was about ten seconds per person. The students' periodontal status was scored as "excellent (+2)," "good (+1)," "questionable (0)," "poor (-1)," or "very poor (-2)" according to the criteria of an Oral Rating Index (ORI) System proposed by the present authors. The level of students' perceptions was assessed by the cognition score of our dental health test (10 items concerning dental attitudes and behavior). Main results were as follows: 1. Only 6% of the 10-th grade students were judged as having "excellent (+2)" oral health. Thirty-six percent were "very poor (-2)" or "poor (-1)" periodontal status. 2. The mean cognition score and the mean ORI score of the 11-th grade students were significantly greater for each sex group than those of the 10-th grade students. 3. The cognition score showed a clear relationship to the ORI score in each grade and in all. The behavioral component of the cognition score was more closely related to the ORI score. These findings suggest that the dental health education contributes to the improvement of periodontal status as well as that of perceptions. Furthermore, the ORI may be utilized for a screening system to evaluate adolescents' periodontal status quickly and effectively.

Adolescent↗