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Biomedical subjects

Y Kawashima

Publications and source records attributed to Y Kawashima.

At least 145 records · Page 8Linked to original sources
PubMed1997

Perfluorodecanoic acid enhances the formation of oleic acid in rat liver.

The feeding of perfluorodecanoic acid (PFDA) to male rats at a dietary concentration of 0.005% (w/w) for 7 days resulted in a marked increase in the activity of microsomal stearoyl-CoA desaturation in the liver. This increase in the overall desaturation activity was due to the induction of terminal desaturase among the components comprising the desaturation system. In contrast, PFDA inhibited desaturation in vitro, seemingly due to interference with electron transport through the desaturation system. Accordingly, PFDA can be an inducer and also an inhibitor of delta9-desaturation. PFDA feeding enhanced the conversion of radioactive stearic acid into oleic acid in the liver in vivo, indicating that the induction of delta9-desaturase by PFDA functions in vivo. PFDA feeding increased the mass of octadecenoic acid (C18:1) in the liver and the proportion of C18:1 in microsomal lipid. A highly significant linear correlation existed between the microsomal desaturase activity and the proportion of C18:1 in microsomal lipid when compared using rats in five different physiological states: control, PFDA-fed, p-chlorophenoxyisobutyric acid (clofibric acid)-fed, starved and starved/refed. These results suggest that the increase in the hepatic level of C18:1 caused by feeding of PFDA to rats can be explained by the common concept of regulation, i.e. the hepatic level of C18:1 is under the control of delta9-desaturase. The dietary administration of PFDA also increased the content of cytochrome P-450 and the activity of 7-ethoxycoumarin O-de-ethylase in the liver.

Acyl Coenzyme A↗
PubMed1997

Fish oil-feeding prevents perfluorooctanoic acid-induced fatty liver in mice.

The effects of perfluorooctanoic acid (PFOA) on the levels of lipids in liver and serum were compared between mice fed a diet supplemented with soy bean oil (SO), perilla oil (PO), or fish oil (FO) for 4 weeks. Hepatic content of triglyceride (TG) was significantly lower in the mice fed the FO diet than that in the mice fed either the SO or the PO diet. The treatment with PFOA caused a marked accumulation of TG in the livers of SO-fed and PO-fed mice (seven- and twofold over their respective controls), whereas a level of TG remained low in the mice fed the FO diet. Incorporation in vivo of [3H]glycerol revealed that FO-feeding reduced synthesis of TG in the liver. The administration of PFOA increased the incorporation of [3H]glycerol into hepatic phospholipid (PL) regardless of the dietary oil, while synthesis of hepatic TG from [3H]glycerol was not altered by the treatment with PFOA. Serum level of TG was reduced by the administration of PFOA to the mice fed either the SO diet or the PO diet, while no change in the level was observed in the mice fed the FO diet. These results suggest that the accumulation of TG in the livers of PFOA-treated mice is due to the inhibition of the secretion of TG into circulation. PFOA-induced hepatic accumulation of TG is prevented by the feeding of the FO diet which inhibits TG formation. Among three dietary oils, FO-feeding alone prevented the PFOA-caused accumulation of TG in the liver. The importance of docosahexaenoic acid (22:6(n - 3)) is discussed in relation to the prevention of fatty liver induced by chemicals.

Animals↗
PubMed1997

Ménétrier's disease evaluated serially by abdominal ultrasonography.

We report the case of a 3-year-old boy with Ménétrier's disease who presented with prominent anasarca associated with hypoproteinemia, but no proteinuria. An early sonogram of the stomach demonstrated thickening of the gastric wall which was found to resolve gradually on serial sonograms. Consequently, we considered that the submucosal layer of the gastric wall was particularly thickened as a result of Ménétrier's disease. A gastric biopsy was performed 18 days after onset of the disease, and an electron-microscopic examination of the sample disclosed persistent widening of gastric tight junctions by more than 10 nm. The patient made a full recovery on supportive treatment in 3 weeks. Ultrasonography provided us with a potent tool not only in making the diagnosis, but also in following the course of the disease.

Abdomen↗
PubMed1997

Cell proliferation on the outer anterior capsule surface after extracapsular lens extraction in rabbits.

PURPOSE: To use light microscopy to evaluate the presence and distribution of cells that proliferate on the outer surface of the anterior capsule after experimental lens extraction in rabbit eyes. SETTING: Research Laboratory, Department of Ophthalmology, Wakayama Medical College, Wakayama, Japan. METHODS: Extracapsular lens extraction, with or without implantation of a poly(methyl methacrylate) intraocular lens, was performed in 10 adult albino rabbits under general anesthesia. Animals were killed 1 month postoperatively. Each eye was embedded in paraffin and examined by light microscopy. RESULTS: A capsular bag composed of the anterior and posterior capsules was observed. Mononuclear cells, presumed to be lens epithelial cells (LECs), had proliferated in the space between the capsules as well as on the outer surface of the anterior capsules, in association with an accumulation of extracellular matrix. CONCLUSION: After lens extraction, LECs migrated to and proliferated on the anterior surface of the anterior capsule.

Animals↗
PubMed1997

Synthesis, structure and quantitative structure-activity relationships of sigma receptor ligands, 1-[2-(3,4-dimethoxyphenyl)ethyl]-4-(3-phenylpropyl) piperazines.

A set of the title compounds having different substituents (R1, R2) on their phenyl groups was synthesized to find sigma receptor binding affinity. Among the compounds, 2b (R1 = R2 = Cl) has the most potent sigma 1-binding activity, while 2a (R1 = R2 = H, SA4503) was most selective to sigma 1 over sigma 2 receptor. The crystal structures of 2a and 2b were shown, by X-ray crystallography, to be similar except for the one torsional angle of their propylene parts. Quantitative structure-activity relationship study suggested the affinity of the compounds to the sigma 1 receptor was dependent on the electronic feature, Swain-Lupton's R or Sz that was derived by molecular orbital method, of R1 and R2.

Analgesics, Opioid↗
PubMed1997

Repair for aneurysms of the entire descending thoracic aorta or thoracoabdominal aorta using a deep hypothermia.

OBJECTIVE: Replacement of the entire descending aorta or of the thoracoabdominal aorta still has a significant risk for postoperative paraplegia. Surgical strategies using a deep hypothermia to protect the spinal cord or viscera are discussed. METHODS: From April 1994, 25 patients underwent graft replacement of the entire descending aorta (13 patients) or thoracoabdominal aorta (12 patients) using a deep hypothermia. Five patients had atherosclerotic aneurysms and 20 had aortic dissection. There were 20 males and 5 females, whose age ranged from 26 to 72 years old, 47 years old in average. Surgery consisted with proximal anastomosis using deep hypothermia (18 degrees C) with retrograde cerebral perfusion by elevating central venous pressure to 20 mmHg, reconstruction of the intercostal arteries, and distal open anastomosis, while perfusing the brain and heart. Proximal open anastomosis was used with retrograde cerebral perfusion technique in 18 patients. Averaged number of reconstructed intercostal arteries was 2.1 for each patient. RESULTS: No early mortality was found and one patient died of respiratory failure 6 months after surgery. One patient had a postoperative stroke and one had a delayed onset of paraplegia 2 days after operation. The cause of paraplegia was secondary hypoxemia and hypotension due to pneumonia. CONCLUSION: Utilization of the deep hypothermia in surgery for aneurysms of the entire descending aorta or of the thoracoabdominal aorta provided an adequate protection of the spinal cord as well as the abdominal viscera, eliminated clamp injury or cerebral embolization of debris or thrombi, and afforded excellent surgical exposures.

Adult↗
PubMed1997

Long-term results of patch repair for saccular aneurysms of the transverse aortic arch.

OBJECTIVE: Long-term results of patch repair in patients with a saccular aneurysm of the aortic arch were investigated. PATIENTS: From December 1984, 43 patients with a saccular aneurysm of the arch underwent patch repair. Indications for patch repair were determined as orifice diameter of aneurysm being less than 1/3 of the total circumference of the aorta. METHOD: Midsternotomy was used in 38 patients, and left thoracotomy in five. Selective cerebral perfusion was used in 28 patients, deep hypothermic circulatory arrest with retrograde cerebral perfusion in eight during the last 3 years, and partial cardiopulmonary bypass in seven. RESULTS: There were five (11.6%) early deaths, and causes were respiratory failure in two patients, low cardiac output in two, and gastrointestinal bleeding in one. Stroke was found in three patients (6.9%). During follow-up, seven patients died, two due to rupture of a residual or pseudoaneurysm, one due to reoperation of pseudoaneurysm, one due to stroke, two due to respiratory failure, and one due to unknown cause. Postoperative survival, including early death, was 69.3% at 5 years and 43.3% at 9 years. Aortic reoperation was done in three patients with a pseudoaneurysm formation and two survived. Freedom from reoperation was 91.7% at 5 years and 38.2% at 9 years. Event free ratio was 79.3 +/- 9.8% at 5 years and 37.6 +/- 18.6% at 9 years. CONCLUSION: Because of a high incidence of pseudoaneurysm or residual aneurysms after patch repair for a saccular aneurysm of the aortic arch, strict criteria for the patch repair should be applied or graft replacement of the aorta is recommended.

Aneurysm, False↗
PubMed1997

Effect of collagen cross-linking in collagen corneal shields on ocular drug delivery.

It is well known that some ocular diseases can be treated more effectively with a collagen shield containing drug. The influence of collagen cross-linking on drug delivery is not known. We determined if collagen cross-linking affects ofloxacin bioavailability at three different collagen shield dissolution times. In this study, the collagen shields were not impregnated in drug but an eye drop was simply instilled after application of collagen shield. A non-cross-linked collagen shield, with a dissolution time of 12 h, disappeared more rapidly from the rabbits' eyes due to proteolysis after application in vivo. On the other hand, the cross-linked collagen shields, with dissolution times of 24 and 72 h, served as an ofloxacin depot and enhanced topical ofloxacin penetration into the cornea and the aqueous humor. As the dissolution times for the cross-linked collagen shield are longer than those of the non-cross-linked type, they serve as drug reservoirs. Therefore, cross-linked collagen shields might be useful ocular drug delivery devices because they can allow drug concentrations to achieve higher levels in the cornea and aqueous humor.

Absorption↗
PubMed1997

Delayed improvement of autonomic nervous abnormality after the Maze procedure: time and frequency domain analysis of heart rate variability using 24 hour Holter monitoring.

OBJECTIVE: To analyse heart rate variability in patients with atrial fibrillation after the Maze procedure, to investigate whether the procedure damages the cardiac autonomic fibres supplying the sinus node. DESIGN AND PATIENTS: Time and frequency domain analyses of RR variability were performed using 24 hour Holter monitoring one month after surgery in 12 patients with atrial fibrillation who underwent the Maze procedure (Maze group) and in seven patients who underwent cardiac surgery without the Maze procedure (control group). Mean RR intervals (mRR) and the standard deviation of successive RR intervals (SDRR) were determined by time domain analysis, and high frequency (HF), low frequency (LF), and total power (TP) spectral components of RR variability were calculated by frequency domain analysis. Holter monitoring was also performed at six and 12 months after cardiac surgery in the Maze group. RESULTS: Circadian variation (mean (SD)) in mRR (daytime to night time difference: 119 (60) v 302 (143) ms), SDRR (daytime: 8.4 (3.3) v 37.0 (12.0) ms), TP (daytime: 46.7 (16.0) v 171.8 (30.4) ms), HF (daytime: 19.6 (9.9) v 36.7 (7.1) ms2), and LF/HF (daytime: 0.31 (0.07) v 1.18 (0.46)) was decreased in the Maze group at one month compared with the control group (p < 0.01), but showed improvement at six and 12 months (p < 0.05). CONCLUSIONS: Surgery combined with the Maze procedure markedly suppressed the circadian variation of heart rate over a 24 hour period within one month after surgery, mainly because of damage to the innervation of the sinus node. However, at six and 12 months there was restoration of circadian variation, probably as the result of reinnervation of the sinus node.

Analysis of Variance↗
PubMed1997

Orthovanadate stimulates cyclic guanosine monophosphate-inhibited cyclic adenosine monophosphate phosphodiesterase activity in isolated rat fat pads through activation of particulate myelin basic protein kinase by protein tyrosine kinase.

Involvement of protein kinases in the stimulation of cGMP-inhibited cAMP phosphodiesterase (PDE) activity by orthovanadate (vanadate) was studied. When the fat pads were incubated with 2 mM vanadate or 10 nM insulin, the stimulation of myelin basic protein kinase (MBPK) activity in the particulate by vanadate reached a maximum at 60 min. In contrast, insulin showed a transient increase at 20 min. A 60-min incubation of the fat pads with vanadate stimulated all activities of protein tyrosine kinase (PTK), MBPK, and PDE in the particulate, in a similar dose-dependent manner. Amiloride, a PTK inhibitor, inhibited the stimulations of three enzymes by vanadate in a similar concentration range. Enzyme fractions, which were separated from the solubilized particulate, were subjected to the immunoblot analysis. A fraction of MBPK was identified to contain a major protein of mol wt (44K) and a minor one (42K), both of which are immunoreactive with a mitogen-activated protein kinase (MAPK) antibody. The partially purified PDE activity was stimulated by the addition of the partially purified MBPK. The further stimulation was observed with the PTK-activated MBPK. These results suggest that vanadate stimulates in part the PDE activity through the activation of the particulate MBPK, probably MAPKs, by PTK sensitive to vanadate.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1997

Salazosulfapyridine suppresses chondrocyte mediated degradation induced by interleukin 1beta.

OBJECTIVE: To investigate the effects of salazosulfapyridine (SASP) and methotrexate (MTX) on interleukin (IL)-1beta treated rabbit chondrocytes. METHODS: Normal rabbit chondrocytes were cultured to confluency. IL-1beta was added to serum-free culture medium in the presence or absence of SASP or MTX. After 2 days' incubation, the effects were evaluated from the responses of metalloproteinases, glycosaminoglycan (GAG), and prostaglandin E2 (PGE2). RESULTS: SASP and MTX suppressed GAG and collagenase release into the culture medium from IL-1beta stimulated rabbit chondrocytes in a dose dependent manner. Only SASP suppressed stromelysin and PGE2 release. CONCLUSION: SASP may have a protective effect on cartilage degradation of patients with rheumatoid arthritis.

Animals↗
PubMed1997

[Low preoperative PaO2 in patients with ovarian and endometrial cancer].

We investigated preoperative PaO2 and changes of PaO2/FIO2 (P/F) during the operation in 40 patients with gynecologic malignancies (ovarian cancer (O group) = 14 cases, endometrial cancer (E group) = 14 cases, cervical cancer (C group) = 12 cases). Preoperative chest X-ray and respiratory function test of our patients were within normal ranges (% VC > or = 80, % FEV 1.0 > or = 70). There were no differences among 3 groups in age, height, weight, % VC, or % FEV 1.0. Preoperative PaO2 values in the O group and E group were significantly lower than the normal value (100--age/4). Preoperative PaO2 and P/F values in the O group were significantly lower in comparison with those in the C group. We suggest, therefore, that it is necessary to measure preoperative PaO2 in patients with ovarian and endometrial cancer.

Adult↗
PubMed1997

[Hemobilia after percutaneous transhepatic gallbladder drainage for cholecystitis in a patient undergoing aortic valve replacement].

A 50-year-old man with hemobilia after percutaneous transhepatic gallbladder drainage (PTGBD) for cholecystitis is presented. PTGBD had been performed for acute cholecystitis following aortic valve replacement. A combination of aspirin and warfarin as anticoagulant therapy had been administrated with the prothrombin time of approximate 40%. Six months later, the patient was again admitted to our hospital because of jaundice, high fever and digestive bleeding. PTGBD was again attempted under the diagnosis of acute cholecystitis. Endoscopic retrograde cholangiopancreatography revealed coagula which were excreted from the papilla of Vater, thus followed by a cholecystectomy accompanying with a choledochotomy. Three ulcers were observed in the cut surface of the resected gallbladder. Microscopic examinations of the gallbladder showed hemorrhage and inflammation. We reported out patient because hemobilia in the chronic phase after aortic valve replacement is rare.

Acute Disease↗
PubMed1997

[Multifocal choroiditis with subretinal fibrosis].

We report 2 cases of multifocal choroiditis associated with subretinal fibrosis on whom the fluorescein fundus angiography (FAG) and the indocyanine green infrared angiography (IA) were performed. Case 1 was a moderately myopic 14-year-old girl who had no ocular symptoms. She had numerous small, round, discrete, partially conflued lesions with subretinal fibrosis scattered in the periphery and one discrete relatively large lesion along the superotemporal arcade in her left fundus. Subretinal fibrosis had progressed in the superior lesion. Some lesions had coalesced into a sword-like pattern over a period of 2 years. Case 2 was a high myopic 18-year-old man who had distorted vision in his right eye. He had some small whitish round lesions with one small choroidal neovascular tissue and subretinal fibrosis in the posterior pole and a sword-like lesion in the inferior periphery. Another choroidal neovascular tissue developed near the macula during the 6-month follow-up period. In FAG, the centers of the lesions hypofluoresced corresponding to the pigmentation and the edges hyperfluoresced. Some of the lesions showed window-defects and others tissue-staining. In IA, all the whole lesions hypofluoresced from an early stage of the angiography and some major choroidal vessels were visible through them. The hypofluorescent areas persisted into the late phase. The hypofluorescent areas of the IA were larger than those seen in FAG and in funduscopy. These findings indicate that the choriocapillaris was initially damaged and consequently the structures of the lesions partly disappeared at the level of the retinal pigment epithelium-choriocapillaris complex.

Adolescent↗
PubMed1997

[Effect of nicotine-administration on tyrosine hydroxylase-containing neuron in the rat forebrain; immunohistochemical study with semiquantitative morphometric analysis].

Nicotine is toxic substance that is absorbed by cigarette smoking and easily causes dependence. It is clear that smoking is bad for health, however, the effects of nicotine itself on the central nervous system have not been elucidated. We studied the effects of nicotine-administration (5 mg/kg x 2/day, 7 days) on immunoreactivity for tyrosine hydroxylase (TH), the rate-limiting enzyme of catecholamine synthesis, in the rat forebrain including the cerebral cortex, hippocampus, striatum and hypothalamus to investigate the influence on catecholaminergic neurons. In the nicotine-administration group, both the number and intensity of TH-immunoreactive fibers and terminals increased in the fronto-parietal cortex, anterior cingulate cortex and hippocampus in comparison with those of the control group, and a significant difference was demonstrated by computer assisted morphometric analysis. These findings suggest that nicotine-administration influences catecholaminergic neural systems in the forebrain, especially in the cerebral cortex and hippocampus and that these effects might be related to developing the dependence on smoking.

Animals↗