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Biomedical subjects

T Kaneda

Publications and source records attributed to T Kaneda.

At least 235 records · Page 13Linked to original sources
PubMed1984

Experimental study of dermal grafts for reconstruction of oral mucosa.

Mucosal defects in the oral cavities of 35 dogs were repaired with reversed dermal grafts, full-thickness skin grafts, and dermal grafts. Comparative observations were made for up to two years to analyze the healing processes. The reversed dermal grafts were covered by surrounding mucosal epithelium and formed normal mucosal tissue that maintained its characteristics for two years. Histologic and scanning electron microscopic examination revealed that the epithelial appendages underwent degeneration, presumably through being embedded by the grafting of the dermis inside out. Epithelialization of the dermal grafts occurred from both surrounding mucosal epithelium and ancillary skin appendages. The full-thickness skin grafts maintained their original structure and function over the two-year observation period. It appears from this investigation that the reversed dermal graft method has definite advantages over full-thickness skin grafting and dermal grafting.

Animals↗
PubMed1984

Dynamic vascular changes in free skin grafts.

Vascular changes in full-thickness skin grafts in rats were examined at various intervals after grafting using microangiography. The grafted skin and its bed showed dynamic vascular changes that were considered to be related to release of an " angiogenetic factor" produced by the skin under oxygen-deficient conditions such as ischemia. The first filling of contrast medium in the grafts was observed 24 hours after grafting. Both primary and secondary revascularization were observed.

Angiography↗
PubMed1984

Liposarcoma of the cheek in an infant.

A case of liposarcoma of the cheek in a 6-month-old infant has been presented. This tumor, one of the most common malignant tumors of soft tissue in the body generally, is exceedingly rare in the head and neck regions, having been reported in this location on only a few occasions. A review of the literature reveals that this patient was one of the youngest so affected. The postoperative course was uneventful, and after three years no evidence of recurrence or metastasis has been observed.

Cheek↗
PubMed1984

Inducer-mediated commitment of murine erythroleukemia cells to terminal cell division: the expression of commitment.

Murine erythroleukemia cells (MELC) are transformed cells that can be induced to differentiate by a variety of agents, such as hexamethylenebisacetamide (HMBA) and dimethyl sulfoxide. Dexamethasone suppresses HMBA-mediated MELC differentiation, but MELC retain a memory for their exposure to HMBA since, on transfer from culture with HMBA and dexamethasone to medium without additions, a portion of the cells express characteristics of terminal differentiation. This study characterizes the steroid suppressed steps in the multi-step process of inducer-mediated MELC terminal differentiation. MELC in culture with HMBA and dexamethasone show low levels of commitment to terminal cell division; upon transfer to culture with inducer alone there is a rapid increase in the proportion of committed cells. The magnitude of this rapid or "step-up" expression of commitment increased with the length of prior culture with inducer and steroid. This step-up expression is not inhibited by actinomycin D or cordycepin but is blocked by cycloheximide. HMBA is required for step-up expression of commitment. In the absence of inducer, there is a rapid decay in the capacity for step-up expression. Thus, HMBA initiates a series of changes leading to the accumulation of factors--which may be mRNAs--whose expression is blocked by dexamethasone. Hemin, which induces MELC accumulation of globin mRNA but not commitment to terminal cell division, cannot, as does HMBA or dimethyl sulfoxide, cause step-up expression of commitment.

Acetamides↗
PubMed1984

Modulation of gene expression during terminal cell differentiation: murine erythroleukemia.

MELC are virus-transformed cells capable of indefinite proliferation that are blocked in differentiation at an early erythroid precursor stage, probably corresponding to CFU-e. A variety of agents, among them HMBA and Me2SO, induce MELC to terminal differentiation and expression of characteristics similar to that associated with normal erythropoiesis. During inducer-mediated terminal differentiation, modulation of expression of a number of genes occurs. Studies to date have characterized inducer-mediated alterations in chromatin structure associated with activation of alpha and beta maj globin genes. Inducer-mediated MELC terminal cell division is also associated with a decrease in the synthesis of the nuclear protein p53, a protein that has been implicated as a requirement for the progression from G1 to S in the cell cycle. HMBA-mediated commitment to terminal cell division is suppressed by steroid. HMBA induces accumulation of mRNAs that may be required for commitment to terminal cell division and whose translation is suppressed by dexamethasone. At least two inducer-activated genes have been identified that may play a role in the transition of terminal cell division.

Animals↗
PubMed1984

Postoperative irradiation after reconstructive surgery: comparative study of radiosensitivity between free-skin grafts and skin flaps.

Radiation effects after reconstructive surgery (free-skin grafts and skin flaps) were studied in the rat, and the optimum time for irradiation was determined. The radiosensitivity of both free-skin grafts and skin flaps showed the same trend depending on time of irradiation after operation. The grafts or flaps irradiated in the hypervascular stage showed severe reactions to irradiation, whereas those irradiated in the hypovascular stage showed milder reactions in gross and microangiographic observation. Vascular damage should be given primary consideration when deciding the proper time for irradiation after reconstructive surgery. In general, free-skin grafts showed more severe reactions than skin flaps, especially in the grafts irradiated in the early stage after operation. The experimental results of this study cannot be readily transferred to a clinical setting, but they suggest that postoperative irradiation could be begun 3 to 4 weeks after operation with respect to graft or flap survival, and the results of the clinical cases almost coincide with these experimental results.

Angiography↗
PubMed1983

Effects of irradiation on grafted skin.

The reaction of grafted skin to irradiation was studied in the rat and the optimum time for irradiation postoperatively was determined. There was a close correlation between the radiosensitivity and the vascularity of the graft and its recipient bed. Grafts showed different reactions depending on the time of irradiation after grafting. Those in the early hypovascular stage showed reactions similar to those of normal control skin. Severe reactions were observed in the hypervascular stage. Grafts in the late hypovascular stage showed more moderate reactions.

Animals↗
PubMed1983

Fatty acid composition and primer specificity of de novo fatty acid synthetase in Bacillus globispores, Bacillus insolitus, and Bacillus psychrophilus.

The fatty acid compositions of three psychrophilic species of Bacillus were determined by gas--liquid chromatography. The proportions of straight-chain fatty acids, branched-chain fatty acids, and unsaturated fatty acids were found to be 13.3, 86.7, and 26.1% of the total cellular fatty acids for Bacillus globispores, 36.6, 63.4, and 25.1% for Bacillus insolitus, and 6.9, 93.1, and 18.4% for Bacillus psychrophilus, respectively. In all three organisms the de novo fatty acid synthetase specificity towards acyl-CoA primers was butyryl-CoA greater than propionyl-CoA much greater than acetyl-CoA. This shows that B. insolitus, which has an unusually large proportion of straight-chain fatty acids for Bacillus, does not possess a different de novo fatty acid synthetase than the other two organisms. Therefore, the greater proportion of straight-chain fatty acids in B. insolitus may be explained by a large supply of straight-chain primer.

Acyl Coenzyme A↗
PubMed1983

Renal contribution to acid-base regulation during the menstrual cycle.

Menstruating women exhibit a light but sustained hypocapnia during the luteal phase. To elucidate whether the hypocapnia results primarily from a respiratory or renal mechanism, we measured the rate of urinary excretion of acid at intervals during the menstrual cycle in five subjects. The acid-base composition of arterial blood in three subjects and end-tidal PCO2 in the remaining two subjects were also determined. During the follicular phase, the acid-base composition of blood and the rate of net acid excretion remained virtually constant. After ovulation, significant decreases in PaCO2 (3.5 mmHg), [HCO3]p (2 meq/liter), and net acid excretion (2 meq/h) occurred in the first 4-6 days of the luteal phase (14 days long). Following this, net acid excretion returned to the preovulatory level. PaCO2 and [HCO3]p, however, remained decreased for 3 more days. At the end of the luteal phase, restoration of PaCO2 proceeded faster than that of [HCO3]p. The acid-base changes in blood and urine observed during the luteal phase were comparable to those occurring during adaptation and recovery from sustained hypocapnia, suggesting that hypocapnia during the luteal phase is primarily respiratory in origin.

Acid-Base Equilibrium↗
PubMed1983

Hypocholesterolemic effect of triterpene alcohols with soysterol on plasma cholesterol in rats.

To identify the synergistic hypocholesterolemic substance found in soybean oil unsaponifiable matter, rats were fed diets containing various fractions of the unsaponifiable matter prepared by silicic acid column chromatography. The plasma cholesterol level of the group fed the alcohol fraction, which mainly consisted of triterpene alcohols, was significantly lower and the effect was synergistic with soysterol. So the effect of cycloartenol and 24-methylenecycloartanol, which are main constituents of triterpene alcohols in soybean oil unsaponifiable matter, was investigated. Both compounds were prepared from gamma-oryzanol (ferulate) and were added (0.05%) respectively to the experimental diet containing 0.5% cholesterol and 1% soysterol. It was observed that both cycloartenol and 24-methylenecycloartanol in combination with soysterol greatly reduced the plasma cholesterol and enhanced cholesterol excretion. This suggests that the hypocholesterolemic activity of dietary vegetable oils may account for not only their fatty acid compositions and sterol contents but also the synergistic hypocholesterolemic effect of triterpene alcohols.

Alcohols↗
PubMed1983

[Prophylactic and chemotherapeutic efficacy of pivmecillinam (PMPC) against infections after TUR-P and prostatectomy].

The prophylactic and chemotherapeutic efficacy of PMPC against infections after TUR-P has been investigated. Bacteriological evaluation: PMPC , 200-300 mg/day for 2-12 weeks, was administered to 49 patients, who had over 10(3)CFU/ml of microorganisms after CET or CEC treatment for 3-7 days. The eradication rate of microorganisms was 40.8% after 2 weeks, 52.2% after 4 weeks, 64.1% after 6 weeks, 65.0% after 8 weeks and 70.6% after 12 weeks. Effectiveness on pyuria : The improvement rate of pyuria against 59 patients who had over 10(5)/hpf of pyuria , was 15.3% after 2 weeks, 16.4% after 4 weeks, 25.4% after 6 weeks, 58.5% after 8 weeks, 72.7% after 10 weeks and 75.0% after 12 weeks. Overall clinical efficacy on PMPC was examined in 26 patients. The results of efficacy were 27.3% after 2 weeks, 48.0% after 4 weeks, 50.0% after 6 weeks, 69.2% after 8 weeks, 75.0% after 10 weeks and 77.0% after 12 weeks. The clinical response was evaluated according to a criterion for clinical evaluation of antimicrobial agent on chronic complicated UTI proposed by UTI committee in Japan. No severe adverse effect including allergic reaction was found. Following administration of PMPC , three patients experienced adverse gastric reactions, and drug administration was discontinued at week 6 or 8. PMPC was effective as a prophylactic chemotherapeutic drug against infections after TUR-P and prostatectomy.

Age Factors↗