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Biomedical subjects

Y Takashima

Publications and source records attributed to Y Takashima.

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

Distribution analysis of transferred donor cells in avian blastodermal chimeras.

Blastodermal chimeras were constructed by transferring quail cells to chick blastoderm. Contribution of donor cells to host were histologically analyzed utilizing an in situ cell marker. Of the embryos produced by injection of stage XI-XIII quail cells into stage XI-2 chick blastoderm, more than 50 percent were definite chimeras. The restriction on the spatial arrangement of donor cells was induced by varying the stage of host. Ectodermal chimerism was limited to the head region and no mesodermal chimerism was shown when the quail cells were injected into stage XI-XIII blastoderm. Mesodermal and ectodermal chimerisms were limited to the trunk, not to the head region, when the quail cells were injected into the stage XIV-2 blastoderm. In these chimeras, however, some of the injected quail cells formed ectopic epidermal cysts. Consequently, the stage XIV-2 blastoderm may become intolerant of the injected cells. Our results suggest that it is possible to obtain chimeras that have chimerism limited to a particular germ layer and region by varying the stage of donor cell injection. Injected quail cells contributed to endodermal tissues and primordial germ cells regardless of the injection site. The quail-chick blastodermal chimeras could be useful in the production of a transgenic chicken and in the investigation of immunological tolerance.

Animals↗
PubMed1992

[The sequential changes of serum acute phase reactants in response to antituberculous chemotherapy].

In order to evaluate the clinical effectiveness of response to antituberculous chemotherapy, we measured the serum levels such of acute phase reactants as C-reactive protein (CRP), alpha-1-acid glycoprotein (alpha 1-AG), haptoglobin, alpha-1-antitrypsin (alpha 1-AT) and sialic acid in 24 patients with pulmonary tuberculosis. Furthermore the relationship between these parameters and other biochemical indicators, such as serum immunoglobulins (IgG, IgA and IgM) and blood erythrocyte sedimentation rate (ESR) were observed. In the case studies of the eighteen prognostically cured patients, the serum levels of alpha 1-AG, haptoglobin, alpha 1-AT and sialic acid were significantly higher than those of healthy controls (P less than 0.01), and were significantly decreased to normal levels within three to five weeks after negative results for tubercule bacilli were obtained in the sputum cultures, while CRP, immunoglobulin and ESR showed a tendency to be lower than the healthy controls. In conclusion, alpha 1-AG, haptoglobin, alpha 1-AT and sialic acid are considered to be the sensitive biochemical indicators capable of being used to predict and monitor the clinical response to antituberculous chemotherapy.

Acute-Phase Proteins↗
PubMed1992

[Pneumonectomy for destroyed lung or chronic tuberculous empyema].

Fourteen patients underwent pneumonectomy for destroyed lung or tuberculous empyema at the Shimada Municipal Hospital from September 1980 to December 1985. Mean age was 61 and ten patients were males. Cough and sputum (in 12 cases) and hemosputum or hemoptysis (in 8 cases) were common complaints. Three patients had complications in the immediate postoperative period: hemorrhagic shock, pulmonary embolism and contralateral pneumothorax. They were treated conservatively. The postoperative course was uneventful in the other patients and all complaints were reduced or disappeared. And lung function improved in 3 cases with chronic empyema compressing the mediastinum. In conclusion, pneumonectomy is one of the radical operation for destroyed lung or chronic tuberculous empyema with low pulmonary function and complaints. And the critical level are 40% of %VC and 25% of FEV1.0/pr. %VC in preoperative pulmonary function.

Adult↗
PubMed1992

Course before and after treatment of a patient with Budd-Chiari syndrome monitored by iodine-123-iodoamphetamine scintigraphy per os and per rectum.

A 55-yr-old woman with Budd-Chiari syndrome was treated by percutaneous transluminal angioplasty with a balloon catheter. Before and after treatment, portal scintigraphy was performed by the administration of [123I]iodoamphetamine per os and per rectum. An enteric capsule was used for the oral administration. Before treatment, the portal shunt index via the superior mesenteric vein was 40.5%; two weeks after treatment, it was 50.2%; and five months after treatment, it was 41.2%. Before treatment, the portal shunt index via the inferior mesenteric vein was 86.0%; two weeks after treatment, it was 87.6%; and five months after treatment, it was 21.8%. The treatment improved the portal circulation through the inferior mesenteric vein only, with little effect on the portal circulation through the superior mesenteric vein.

Amphetamines↗
PubMed1991

Studies on antiatherosclerotic agents. Synthesis of 7-ethoxycarbonyl-4-formyl-6,8-dimethyl-1(2H)-phthalazinone derivatives and related compounds.

Derivatives of 7-ethoxycarbonyl-4-formyl-6,8-dimethyl-1(2H)-phthalazinone and closely related compounds were synthesized using Wittig and epoxidation reactions. Ring opening amination of the epoxides were carried out using dimethylaluminum amide reagents under mild reaction conditions. beta-Keto ester and beta-diketone moieties were introduced through diazo derivatives. These moieties were reacted with hydrazine hydrate to produce 4-pyrazolyl derivatives. The derivatives were tested for their inhibitory effect on platelet aggregation, and their relaxing effect on blood vessels.

Animals↗
PubMed1991

[Relations of serum apolipoprotein A-I, A-II and B levels to smoking, drinking and body mass].

To examine whether the serum apolipoprotein A-I level (Apo A-I), serum apolipoprotein A-II level (Apo A-II) and serum apolipoprotein B level (Apo B) are related to cigarette-smoking habits, drinking frequency and body mass index (BMI) independent of serum lipoprotein cholesterol levels (HDLC, LDLC or VLDLC), we statistically analyzed the data on Apo A-I, Apo A-II, Apo B, HDLC, LDLC and VLDLC and the life style data obtained from health examinations of 256 male residents aged 40 to 49 mostly randomly selected from two Japanese areas, Ninohe, Iwate and Ishikawa, Okinawa. The results were as follows: (1) HDLC was strongly positively correlated with Apo A-I and Apo A-II, while Apo B was strongly correlated with LDLC and VLDLC. (2) According to univariate analyses, Apo A-I, Apo A-II, Apo B, HDLC, LDLC and VLDLC were not associated with smoking. On the other hand, drinking frequency was positively associated with Apo A-I, Apo A-II and HDLC. Apo A-I and HDLC were negatively correlated with BMI, whereas Apo B, LDLC and VLDLC were positively correlated with BMI. (3) According to the results of multi-dimensional analyses of covariance, Apo A-II was positively correlated with drinking frequency independent of Apo A-I and HDLC, especially among the individuals with increased HDLC. The same multivariate analysis showed that Apo B was positively associated with smoking independent of LDLC and VLDLC among the individuals without increased VLDLC. From these results, we conclude that Apo A-II may be effective as a biological marker for alcohol drinking independent of Apo A-I and HDLC, while cigarette smoking may affect Apo B through a certain direct mechanical effect. (4) Increased HDLC in obese individuals (BMI greater than or equal to 27) or non-drinkers was associated with remarkably increased Apo A-I, while decreased HDLC in thin individuals (BMI less than 21) was associated with remarkably decreased Apo A-II.

Adult↗
PubMed1991

An evaluation of efficacy of cigarette smoking cessation in preventing low levels of serum high-density lipoprotein (HDL) cholesterol.

Correlation of serum high-density lipoprotein cholesterol (HDL-C) with cigarette smoking and alcohol consumption habit was investigated in 562 male office workers aged 31 to 60 yr. HDL-C concentrations were found to be positively associated with alcohol consumption in subjects with relative weight below 10%, but a positive association was not observed in obese subjects having relative weight of 10% or above. In contrast, HDL-C levels were significantly lower in smokers than in non-smokers regardless of obesity. The effectiveness of smoking cessation in preventing low levels of serum HDL-C was estimated by comparing prevalence rates of HDL-C levels lower than an arbitrarily determined HDL-C cutoff value in smokers with those in non-smokers. The estimation was made with unadjusted subjects and also with subjects adjusted for age, relative weight and alcohol consumption. The effectiveness was found to be considerably high in heavy smokers having lower HDL-C levels (less than or equal to 35 mg/dl) with or without hypercholesterolemia (greater than or equal to 220 mg/dl) and further remarkably high in all smokers having hypertriglyceridemia (greater than or equal to 300 mg/dl) besides lower HDL-C levels. It is therefore expected that health education focused on stopping smoking can produce favorable alterations in HDL-C for preventing coronary heart disease, especially in heavy smokers having low serum HDL-C levels concomitant with hypercholesterolemia and/or hypertriglyceridemia.

Adult↗
PubMed1990

Cytochemical demonstration of NPPase activity for detecting proton-translocating ATPase of Golgi complex in rat pancreatic acinar cells.

An attempt at cytochemical demonstration of acidification proton-translocating ATPase (H(+)-ATPase) of Golgi complex in rat pancreatic acinar cells has been made by using p-nitrophenylphosphatase (NPPase) cytochemistry which is used for detecting of Na(+)-K(+)-ATPase (Mayahara et al. 1980) and gastric H(+)-K(+)-ATPase (Fujimoto et al. 1986). K(+)-independent NPPase activity was observed on the membrane of the trans cisternae of Golgi complex, but not inside of cisternae. The localization of NPPase activity is different from that of acid phosphatase activity where reaction products were seen on the inside of the trans Golgi cisternae. Since this activity was insensitive to vanadate, ouabain and independent of potassium ions, it was distinct from plasma membranous ATPases such as Na(+)-K(+)-ATPase and Ca2(+)-ATPase. The K(+)-independent NPPase activity was diminished by the inhibitors of H(+)-ATPase such as N-ethylmaleimide (NEM) and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS). The NPPase reaction products were also seen on the membranes of other acidic organelles, i.e., lysosomes, endosomes, autophagosomes and coated vesicles. These results suggest that NPPase activity on the membrane of the Golgi complex and other acidic organelles corresponds with H(+)-ATPase which plays a role in acidification.

Animals↗
PubMed1990

Dose-response study of N-nitrosomethyl(2-hydroxypropyl)amine-induced nasal cavity carcinogenesis in rats.

Dose response to the carcinogenic activity of N-nitrosomethyl(2-hydroxypropyl)amine (MHP) was investigated for the nasal cavity of male Wistar rats. MHP dissolved in 0.9% saline was administered intraperitoneally once a week for 12 weeks at doses of 0, 4.4, 8.8 and 17.6 mg/kg body weight, and all surviving animals were sacrificed 26 weeks after the beginning of the experiment. Hyperplasias, papillomas and squamous cell carcinomas were induced. Hyperplasias could be divided into flat, protruding and downgrowth types and were observed in respiratory and squamous epithelial regions. Papillomas and squamous cell carcinomas developed in the respiratory region, and the incidence of the latter reached 83% in rats which received the highest dose of MHP. These results indicate that MHP shows its carcinogenic activity of the nasal cavity by the development of squamous cell carcinomas.

Animals↗
PubMed1990

Lack of hepatocarcinogenic potential of acetaminophen in rats with liver damage associated with a choline-devoid diet.

The potential carcinogenic activity of acetaminophen (paracetamol, APAP) was studied in male F344 rats with pre-existing liver damage induced by a choline-devoid (CD) diet. In a short-term experiment, APAP was administered by intragastric intubation as single doses of 0.5-1.5 g/kg body wt after 4 weeks feeding of CD diet had produced fatty livers in rats. Two-thirds partial hepatectomy was performed 4 h subsequent to the initiating treatment step. After a 2 week recovery period, all rats were subjected to the selection procedure of Cayama et al. and killed at week 9 of the experiment. Quantitative analysis of placental form glutathione S-transferase (GST-P)-positive liver lesion development did not reveal any enhancement by APAP, whereas administration of a non-necrogenic dose of diethylnitrosamine (20 mg/kg body wt) in the same protocol demonstrated significant promotion, confirming the utility of the model for detection of weak carcinogenicity of chemicals. In the second long-term experiment, APAP was fed at doses of 0.45 and 0.9% for 25 weeks following 27 weeks administration of CD diet which produced liver cirrhosis in the rats. Despite a slight enhancement of focal liver lesions positive for gamma-glutamyltranspeptidase (GGT), no significant promotion of GST-P-positive altered foci or nodules was observed. In contrast, continuous feeding of CD diet or 0.5% phenobarbital treatment after generation of cirrhosis with CD diet clearly enhanced the induction of both GST-P and GGT-positive liver lesions. Thus, these results indicate that APAP does not possess significant carcinogenic activity in damaged rat liver.

Acetaminophen↗
PubMed1990

Influence of timing of administration of liposome-encapsulated superoxide dismutase on its prevention of acetaminophen-induced liver cell necrosis in rats.

The possible participation of acute oxidative stress in the in vivo mechanism by which acetaminophen (APAP) induces hepatocellular injury was examined. Male Sprague-Dawley rats were administered 3-methylcholanthrene, fasted for 18 h, then given APAP and sacrificed after a further 6 h of fasting. Extensive centrilobular liver cell necrosis along with markedly elevated serum activity of aminotransferases was observed. Liposome-encapsulated human recombinant Cu-Zn superoxide dismutase (LSOD) administered 1 or 0.5 h prior to APAP or simultaneously with the toxin completely prevented APAP-induced hepatocellular injury. In contrast, LSOD administered 5 or 2.5 h before or 1, 2.5 or 5 h after the toxin treatment did not prevent APAP toxicity. Incomplete protection against APAP-induced injury was obtained when LSOD was administered 0.5 h after the toxin. These results support the proposal of an oxidative mechanism for APAP hepatotoxicity.

Acetaminophen↗
PubMed1990

Pathfinding during spinal tract formation in the chick-quail chimera analysed by species-specific monoclonal antibodies.

In order to analyse the spinal tract formation at early stages of development in avian embryos, chick-quail spinal cord chimeras were prepared and species-specific monoclonal antibodies (MAb) were developed. MAbs CN, QN and CQN uniquely stained chick, quail, and both chick and quail nervous tissues, respectively. All three antibodies appeared to bind to the same membrane molecule, but to different epitopes. Cord reversal revealed the features of axonal growth of both cord interneurons and dorsal root ganglion cells. Quail cord interneurons grew along an originally ventral marginal layer in the quail cord transplanted in a reversed position, then turned toward the ventral side at the boundary between the graft and the host, and grew along the host chick ventral marginal layer. Central axons of dorsal root ganglia were restricted to the ventrolateral region of the cord which originally formed the dorsal funiculus. These results suggest that cord interneurons and dorsal root ganglion cells actively select to grow along specific regions of the cord and that spinal tract formation appears to be determined by cord cells, and not by sclerotome cells.

Animals↗
PubMed1990

Indomethacin sustained-release suppositories containing sugar ester.

We prepared indomethacin (IM) sustained-release suppositories using sugar ester (SE) as an additive. The suppositories were prepared by the fusion method with IM, SE, and Witepsol H-15 (H-15) and their availabilities in vitro and in vivo were evaluated mainly by the drug release test and the absorption test in rabbits, respectively. The softening point of the suppositories increased with increasing SE content. In the release test with the Muranishi method, slow-release profiles were obtained when the SE content was more than 52.5%. The absorption of IM from these suppositories, however, was very little. In the other release test, e.g. immersion method with gauze, all of the suppositories with SE showed slow-release profiles, and the drug release rates clearly depended on the SE content. The drug was released from the suppositories by the following leaching-type mechanism proposed by Higuchi. The suppository with a 30% SE content showed a sustained-plasma level of IM, but the other suppositories did not. It was concluded that an appropriate content of SE (i.e. 30%) in the suppository base was required to obtain sustained-release because it reasonably regulated the infiltration of rectal fluid into the suppository and the mechanical strength of the suppository against disintegration.

Animals↗
PubMed1990

Indomethacin sustained-release suppositories containing sugar ester in polyethylene glycol base.

Indomethacin (IM) sustained-release suppositories were prepared by the fusion method using sugar ester and polyethylene glycol 4000 (PEG). The suppositories were evaluated by in vitro release testing, X-ray analysis and in vivo absorption testing in rabbits. X-ray analysis showed that IM was amorphous in PEG-base suppositories. In a release test, slow-release was obtained when the sugar ester content of a suppository was 60%. The IM plasma level following the administration of the suppository was well sustained in the absorption test. The main slow-release mechanism is considered to be the release of IM from the matrix composed of sugar ester and PEG, which is represented by the Higuchi equation. A good correlation between the release test and the absorption test was obtained. It is considered that the amorphous state of IM in this type of sustained-release suppository would enhance the release and absorption of IM in the rectum of the rabbit, whose rectal fluid volume is small.

Animals↗
PubMed1990

[Relative weight and mortality during a five-year follow-up study in an aged population--a study of aged inhabitants of a rural area in Japan].

The present study, a follow-up study for 669 aged examinees of a health check performed in July 1983 in a rural area in Fukushima Prefecture, was conducted to clarify the relationship between relative weight and mortality among aged individuals living in a Japanese rural area. Using the standard body weights calculated from Japanese mean body weights by sex, age class (60-69 and 70 or more) and height cited from the data of the Ministry of Health and Welfare from 1966, mortalities during the five year follow-up were compared among four groups different in relative weight at baseline. The results are as follows. 1) The mortalities in the group of 'Relative weight less than or equal to -10% the leanest group among the four groups, were highest in both sexes, 52.8 per 1000 person-years for males and 33.2 per 1000 person-years for females. On the other hand, those in the group of '+10% less than or equal to Relative weight less than +20%' were lowest in both sexes, 23. 1 per 1000 person-years for males and 7.0 per 1000 person-years for females. In females, the difference in the mortality between these two groups was statistically significant at the 0.05 level, provided age structures in both groups were taken into consideration. 2) In both sexes, the mortalities of cancer and cerebrovascular disease in the group of 'Relative weight less than or equal to -10%' were highest among the four groups, whereas such mortalities in the group of '+10% less than or equal to Relative weight less than +20%' were lowest.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗