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Biomedical subjects

I Kato

Publications and source records attributed to I Kato.

At least 505 records · Page 28Linked to original sources
PubMed1989

[Effects of scaling and root planing on clinical parameters and bacterial flora in periodontal pockets. 1. Changes in clinical parameters and subgingival bacterial flora after treatment].

The purpose of this study was to clinically and microbiologically evaluate the effects of supragingival plaque control, scaling and root planing on periodontal therapy. Six patients affected with moderate or severe periodontitis were selected. The clinical status of each patient was recorded with such clinical parameters as probing pocket depth (PD), probing attachment level (PAL), gingival crevicular fluid flow (GCF), gingival index (GI), gingival bleeding index (GBI), suppurative index (SI), and mobility (Mo). After the patients had learned to perform their own oral prophylaxis, they were treated by scaling and root planing. Microbiological status was assessed by phase contrast microscopy and bacterial forms were classified into following six groups: coccoid cells, rods, filaments, fusiforms, motile rods, spirochetes. The number and the relative proportion of each group were compared statistically. Clinical and microbiological status from baseline to 5 months after scaling and root planing were re-examined. The results obtained were as follows. 1. The most significant change in clinical and microbiological status was observed one month after scaling and root planing. In particular, the total number of the microorganisms and the number and relative proportion of motile organisms were reduced. 2. Thereafter clinical and microbiological status was maintained during experimental period by means of supragingival plaque control.

Dental Plaque↗
PubMed1989

[Effects of scaling and root planing on clinical parameters and bacterial flora in periodontal pockets. 2. Correlation between decrease of probing pocket depth and pretreatment status].

Scaling and root planing is one of the most fundamental and effective procedures in periodontal therapy. The purpose of this study was to investigate statistically whether clinical or microbiological parameters before treatment are related to changes in probing pocket depth (PD). Two kinds of numerical values represented changes in PD. One was pocket difference (A-B: A; PD before the treatment and B; PD after treatment) and the other was rate of pocket decrase [(A-B)/A x 100]. Twenty four sites in six patients with periodontal pockets deeper than 4 mm were selected for this study. Clinical parameters such as PD, probing attachment level (PAL), gingival crevicular fluid (GCF) volume, gingival bleeding index (GBI) and suppurative index (SI) were recorded at each site. Subgingival plaques sampled at the same site were evaluated by phase contrast microscopy. The results obtained were as follows: 1. Of all the clinical parameters changes in PD were most positively correlated with PD before treatment. 2. The microbiological approach revealed that total bacterial count divided by PD value was more negatively correlated with changes in PD than total bacterial number. It was further, revealed that numbers of rods and motile bacteria were more closely correlated with changes in PD than the counts of bacterial groups. At sites where coccoid cells were relatively dominant, PD tended to decrease readily. Motile bacteria, on the other hand, exhibited just the opposite relationship. These results suggest that periodontal treatment should be more effective in periodontal pockets harboring both smaller numbers of rods and motile bacteria.

Dental Scaling↗
PubMed1989

Comparative study on computed tomography and neurotological findings in spinocerebellar degeneration.

The classification of SCD on the basis of the neurotological findings was with classification based on CT findings in 40 cass of SCD. The areas of pons, cerebellar hemisphere, vermis and posterior fossa on CT films were measured by craniometer, and were compared in order to estimate the degree of atrophy. From these assessments, patients were classified into 3 types as follows; (1) 14 cases of cerebellar type, (2) 9 cases of brain stem type and (3) 17 cases of combined type. The classification of SCD based on the neurotological findings including the findings of gaze test, positioning test, eye tracking test, OKN, and fixation suppression test of caloric nystagmus, was well correlated to the classification based on CT findings. From the results, neurotological examination was demonstrated to make a contribution to the estimation of lesions and types in SCD.

Caloric Tests↗
PubMed1989

cDNA cloning of human calpastatin: sequence homology among human, pig, and rabbit calpastatins.

cDNA of human calpastatin, an inhibitor protein specific for calpain (EC 3.4.22.17; Ca2(+)-dependent cysteine proteinase) was isolated by screening of a library prepared from human liver mRNA with pig calpastatin cDNA fragment as a probe. The primary structure of human calpastatin was deduced from the nucleotide sequence of the cDNA and compared with that of pig and rabbit calpastatins already reported. Human calpastatin consisted of 673 amino acid residues and had 78% and 77% identity to pig or rabbit calpastatins, respectively. Human calpastatin had a domain structure with four internally repetitive sequences and one N-terminal non-homologous sequence like the other calpastatins. Human calpastatin had two deletions, 22 and 13 residues long in domain L and domain 1, respectively, compared to pig or rabbit calpastatins.

Amino Acid Sequence↗
PubMed1989

[Mechanism of hypercalcemia associated with malignancy: interactions between induction of hypercalcemia and autonomous growth in VX2 cancer cells].

Hypercalcemia is one of well-recognized paraneoplastic syndromes and occurs occasionally in patients with oral cancers. Because bone is the richest source of calcium in the body, it has been proposed that humoral bone resorbing factors which are released by tumors are responsible for the pathogenesis of hypercalcemia. In the present study, partial purification and identification of bone resorbing humoral factors were carried out employing VX2 squamous cell carcinoma which has been known to induce hypercalcemia in rabbits. In addition, extra- and intra-cellular mechanisms which are operating to confer autonomous growth on VX2 cancer cells were also studied. VX2 carcinoma induced marked hypercalcemia not only in rabbits but also in nude mice in parallel with tumor enlargement. Administration of indomethacin (INDO), a prostaglandin (PG) synthesis inhibitor, before onset of the hypercalcemia prevented an elevation of serum calcium levels and growth of the tumor. INDO, however, failed to decrease serum calcium levels and tumor growth when administered after development of the hypercalcemia and tumor enlargement. These results indicate that not only PGs but other humoral factors are involved in the pathogenesis of the hypercalcemia seen in VX2 cancer-bearing animals. VX2 cancer cells in culture retained their cancerous phenotypic properties, synthesized PGE2, PGF2 alpha and 6-keto PGF1 alpha and secreted highly levels of PGE2, a powerful bone resorber, into the culture medium in a time- and cell density-dependent manner. The culture supernatants also contained a trypsin- and heat-sensitive bone risorbing factor (BRF) with a molecular weight of approximately 20kD. BRF was presumed to be similar to parathyroid hormone related protein (PTHrP) from its biological and biochemical behaviors. Both PGE2 and PTHrP promoted VX2 cell growth, thus suggesting that these two substances are autocrine growth factors for VX2 cells. Calcium stimulated VX2 cell growth and secretion of PGE2 and BRF (PTHrP) in a concentration-dependent fashion. Stimulation of VX2 cell proliferation by PGE2 and PTHrP was closely correlated with a transient elevation of intracellular free calcium ion ([Ca2+]i). [Ca2+]i elevated transiently in response to PGE2 and PTHrP was shown to be supplied by influx of extracellular free calcium ion ([Ca2+]e) through calcium channel present in plasma membrane. Involvement of protein kinase C in autocrine growth stimulation of VX2 cells by PGE2 and PTHrP was unclear. These results demonstrate that PGE2 and PTHrP secreted by VX2 cancer cells not only induce hypercalcemia but promote VX2 cell growth as autocrine growth factors.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1989

[The epidemiology of cancers of the female genital organs].

According to the Vital Statistics of Japan, the age-adjusted mortality rates for cancers of the uterus (all parts), the cervix uteri, the placenta (choriocarcinoma), the vagina and the vulva, have been decreasing while those for cancers of the ovary, the fallopian tube and the corpus uteri have been increasing. The standardized mortality ratio of uterine cancer (all parts) is generally higher in the western parts of Japan and that of ovarian cancer is generally higher in the northern parts of Japan. From international comparisons, the Japanese female shows lower incidences of cancers of the ovary, the corpus uteri, the vagina, and the vulva and higher incidences of cervical cancer and choriocarcinoma.

Choriocarcinoma↗
PubMed1989

[An autopsy case of cerebral astrocytoma associated with multiple myeloma].

A case of cerebral astrocytoma associated with a systematic multiple myeloma is reported. A 76-year-old man was admitted to our hospital because of left hemiparesis. The CT scan revealed a cystic tumor at the right parietal lobe. A serum protein electrophoresis showed a monoclonal peak in the region of gamma-globulin, and examination of bone marrow revealed 15% of atypical plasma cells. After irradiation and chemotherapy, the patient suffered from DIC syndrome and died. Autopsy findings revealed a cerebral astrocytoma and bone marrow infiltration by myeloma cells in the sternum, vertebrae, costae, pelvis, and so on. So we finally diagnosed this case a cerebral astrocytoma with systematic multiple myeloma. In spite of the fact that systematic multiple myeloma is frequently accompanied with cancers at other sites (so called multiple primary cancers), the coexistence of a cerebral astrocytoma and systematic multiple myeloma is extremely rare. Complications of multiple myeloma with other tumors are reviewed.

Aged↗
PubMed1989

Alcohol consumption and cancers of hormone-related organs in females.

The relations between alcohol consumption and cancers of the breast, corpus uteri and ovary were investigated in a case-control study involving 1,740 cases of breast cancer, 239 cases of cancer of the corpus uteri, 417 cases of ovarian cancer and 8,920 controls with other cancer sites identified from the Aichi Cancer Registry, Japan 1980-1986. The age-adjusted relative risk (RR) of daily alcohol drinkers compared to non-drinkers was significantly increased for breast cancer (RR = 1.36, 95% confidence interval (CI) 1.04-1.78), that for cancer of the corpus uteri was lowered insignificantly (RR = 0.44, 95% CI 0.15-1.38) and that for ovarian cancer was significantly lowered (RR = 0.38, 95% CI 0.16-0.90). The increase in the risk of breast cancer associated with daily alcohol drinking was evident in the age range 50 and over, the risk specified by type of alcoholic beverage being highest for beer. Multivariate analyses controlled for age, residence, marital status, occupation, smoking habit and family history of breast cancer did not materially change the RRs of daily alcohol drinkers. Despite the several limitations of the study, the results were consistent with those of previous studies from other countries, suggesting that alcohol consumption may contribute to the risk of breast cancer in Japanese woman, as it dose elsewhere. The present study also suggested alcohol consumption not to be associated with elevated risks of cancer in other hormone-related organs in females, and possibly to be associated with a decreased risk of ovarian cancer.

Adult↗
PubMed1988

Role of the nucleus of the optic tract of monkeys in optokinetic nystagmus and optokinetic after-nystagmus.

A previous experiment disclosed that unilateral lesions of the nucleus of the optic tract (NOT) in the fascicularis monkey resulted in selective loss of optokinetic nystagmus (OKN) towards the lesioned side. This may suggest that the NOT in monkeys, as in non-primates, represents the first relay station in the basic horizontal optokinetic path. This monkey, however, did not show a rapid rise in OKN velocity in response to steps in stimulus velocity. In the present experiments, effects of NOT lesions upon both the rapid and the slow rise of OKN as well as optokinetic after-nystagmus (OKAN) were examined in 6 fuscata monkeys. In 3 with total NOT lesions of 6 monkeys, none of the slow rise OKN or OKAN slow phase velocity were produced towards the lesioned side. In one of the remaining 3 monkeys with partial NOT lesions, a slow rise OKN and OKAN slow phase velocity were selectively reduced towards the lesioned side. In 2 of these 4 monkeys whose lesions were localized in the lateral portions of the pretectum, rapid rise in OKN velocity remained unchanged, whereas in the remaining two whose lesions were large enough to extend into the medial portions of the pretectum near the nucleus of the posterior commissure, rapid rise in OKN velocity was reduced. In the remaining 2 monkeys whose NOT was only superficially damaged, all components of OKN were normal. Other visually induced eye movements were normal. In all monkeys except for one who had marked spontaneous nystagmus, the peak velocity of vestibular nystagmus was not affected after NOT lesions. These findings indicate that the dynamics of the charge of the velocity storage mechanism is separately influenced by NOT lesions: OKN and OKAN are abolished, but vestibular nystagmus remains unaffected.

Animals↗
PubMed1988

Correlation between increase in Ia-bearing macrophages and induction of T cell-dependent antitumor activity by Lactobacillus casei in mice.

When Lactobacillus casei YIT 9018 (LC 9018) or Corynebacterium parvum, known to be immunomodulators possessing antitumor activity, were injected i.p. into BALB/c mice, peritoneal exudate macrophage Ia antigen detected by indirect immunofluorescence method was expressed on their cell surface, but it was not expressed following the injection of 10% proteose peptone, an inflammatory agent, or Lactobacillus fermentum YIT 0159 (LF 0159), which have no antitumor activity. The percentage and absolute number of Ia-positive peritoneal macrophages were maximum on the 7th day after the injection of LC 9018. Immunization by injection of Meth A fibrosarcoma cells treated with mitomycin C (MMC-Meth A) 7 days after LC 9018 injection suppressed the growth of Meth A implanted i.p. 14 days after MMC-Meth A injection. A shorter interval between the injections of LC 9018 and MMC-Meth A did not allow suppression of Meth A growth. These results showed that the increase in Ia-positive macrophages in the peritoneal cavity coincided with the effective interval for induction of the antitumor activity by LC 9018. The antitumor activity induced by injections of LC 9018 and MMC-Meth A did not affect the growth of RL male 1 leukemic cells, syngeneic to BALB/c mice. Neutralization (Winn type) tests showed that peritoneal T lymphocytes possessed tumor cytotoxicity and that the antitumor capacity was reduced by in vivo treatment with anti I-Ad monoclonal antibody simultaneously with and 1 day prior to MMC-Meth A injection. These results indicate that LC 9018-induced Ia-positive macrophages, which first encounter a tumor antigen in the peritoneal cavity, play an important role in the in vivo induction of tumor specific T cell-mediated antitumor immunity.

Adjuvants, Immunologic↗
PubMed1988

Inhibitory effects of prostaglandin E1 on T-cell mediated cytotoxicity against isolated mouse liver cells.

The effects of prostaglandin E1 on cell-mediated cytotoxicity against hepatocytes were investigated using an in vitro cytotoxic assay system. Isolated liver cells from normal C57BL/6 mice were used as the target cells, and effector cells were obtained from spleens of C57BL/6 mice in which experimental hepatitis had been induced by immunization with syngeneic liver antigens. In this assay system, spleen T cells adhering to nylon wool demonstrated a high cytotoxic activity against target liver cells. The cytotoxicity was markedly reduced by prostaglandin E1 at concentrations greater than 10(-7) M. Maximum suppressive activity was obtained when prostaglandin E1 was continuously present during the assay period. By contrast, indomethacin, a specific inhibitor of prostaglandin synthesis, enhanced the cytotoxic activity of effector cells. These data seem to indicate that exogenously added prostaglandin E1 has an inhibitory effect on cell-mediated cytotoxicity of effector spleen cells against target hepatocytes.

Alprostadil↗
PubMed1988

Prevalence and long-term prognosis of mild hypertensives and hypertensives in a Japanese community, Hisayama.

The prognosis and outcome for mild hypertensives (90 mmHg less than or equal to diastolic pressure less than or equal to 104 mmHg) and hypertensives (diastolic pressure greater than or equal to 105 mmHg) was prospectively studied in Hisayama, Japan, and compared between 1621 subjects aged 40 years or over, recruited in 1961, and 2053 subjects recruited in 1974. Each cohort was studied in a follow-up which lasted 10 years. The pharmacological treatment of hypertension proved effective among residents recruited in 1974: the survival rate had favorably improved, and the rates of mortality from cerebral stroke and morbidity from intracerebral stroke and morbidity from intracerebral hemorrhage declined significantly in mild hypertensives and hypertensives in the more recently recruited population. The management of mild hypertension was considered more likely to be effective in reducing stroke than in reducing coronary heart disease in the Japanese general population.

Adult↗
PubMed1988

Prognosis and outcome of elderly hypertensives in a Japanese community: results from a long-term prospective study.

A long-term prognosis and outcome study of elderly hypertensives (aged 60 years or over) was made based on the 20-year prospective population survey conducted in a Japanese rural community (Hisayama) and the results were compared with those for younger subjects (aged 40-59 years). The risk of cardiovascular mortality related to blood pressure level increased with the elevation of either systolic or diastolic pressure in both younger and elderly groups. Cardiovascular mortality increased markedly at a systolic pressure of greater than or equal to 160 mmHg, or a diastolic pressure of greater than or equal to 100 mmHg for those aged 40-59 years. There was no cut-off level for increased risk of cardiovascular mortality for either systolic or diastolic pressures for those aged 60 years or over. Stroke mortality was seven times higher in systolic, and 10 times higher in diastolic hypertensives than in normotensives (P less than 0.01) for the group aged 40-59 years. However, deaths due to stroke and heart disease were more frequently associated with borderline (relative risk 2.3 and 2.3, respectively; P less than 0.01), systolic (relative risk 3.2 and 3.7, respectively; P less than 0.01) and diastolic hypertension (relative risk 2.1 and 4.8, respectively; P less than 0.01), compared to normotension for those aged 60 years or over. Intracerebral hemorrhage and cerebral infarction occurred more frequently in diastolic hypertensives for both young (relative risk 9.8 and 4.8, respectively; P less than 0.01) and elderly subjects (relative risk 3.4 and 1.5, respectively; P less than 0.01) than in normotensives.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

A comparative epidemiologic study on geographic distributions of cancers of the lung and the large intestine in Japan.

To examine what kinds of factors could have caused the geographic variation observed in lung cancer morbidity in Japan, a correlation study was performed comparing various regional traits. The same study was also conducted on large intestinal cancer, aiming to distinguish the possible urban factors associated with both cancers. Lung cancer was highly correlated with industrialization-related factors such as localization of manufacturing industries, automobile traffic and air pollution, whereas colon cancer was correlated with the population density of workers in the tertiary industries such as services, trade and government. A multiple regression analysis could not detect any single factor with an exceptionally strong influence on either cancer. The present findings suggest that the hazardous environmental condition of urban areas has, to some extent, contributed to the recent increase of lung cancer cases in this country.

Age Factors↗
PubMed1988

Factors related to late menopause and early menarche as risk factors for breast cancer.

To investigate underlying factors of late menopause and early menarche which are regarded as risk factors for breast cancer, we analyzed the relationships between ages at menarche and menopause, and other environmental and physical factors using the data of a population-based survey conducted in Aichi Prefecture, Japan. The analysis on menopause was based on 3,148 women aged 55 or more and the analysis on menarche was based on 16,392 women aged 40 or more. These subjects were grouped into three groups (early, average and late groups) according to their ages at menopause and menarche. Women with late menopause had larger height, weight and body mass index and included more professional, administrative and office workers, more daily fish & shellfish consumers and more women with colorectal cancer history of the mother and less current smokers. Women with early menarche also had larger height, weight and body mass index and more residence in a metropolitan area and consumed more bread, meats, fish & shellfish, vegetables, fruits, milk and black tea and less rice, miso soup and pickles. In a multiple regression analysis, occupation, weight, daily or occasional drinking and daily intake of fish & shellfish were positively and smoking was inversely associated with late menopause, while residence in a metropolitan area, weight and daily intakes of bread, milk and green-yellow vegetables were positively associated with early menarche. These results suggest the importance of underlying factors of early menarche and late menopause in the etiology and prevention of breast cancer.

Aged↗