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Biomedical subjects

T Okamura

Publications and source records attributed to T Okamura.

At least 685 records · Page 38Linked to original sources
PubMed1985

Serum CEA levels facilitate detection of recurrences of cancer in patients after gastrectomy.

In an attempt to assess the usefulness of carcinoembryonic antigen (CEA) for predicting the progression of gastric cancer, CEA productivity was evaluated according to serum CEA levels, at the time of recurrence or relapse. In cases of a recurrence, abnormal CEA levels were observed in 14 of 17 (82.4 per cent) with differentiated carcinoma and in 9 of 21 (42.9 per cent) with undifferentiated carcinoma. Preoperative abnormal CEA levels were observed in only 6 of 41 patients (14.6 per cent). A median lead time of manifestation of recurrence was 5 months. In those with relapse, 9 of 11 (81.8 per cent) patients with differentiated carcinoma and 13 of 18 (72.2 per cent) with an undifferentiated carcinoma had abnormal CEA levels. Preoperative abnormal CEA levels were observed in 24 of these 89 patients (27.0 per cent). Postoperative monitoring of CEA seems to be useful for early recognition of gastric cancer progression, irrespective of the preoperative CEA levels.

Adenocarcinoma↗
PubMed1985

Prognostic study of intramucosal carcinoma of the stomach with DNA aneuploidy.

Cell nuclear DNA content was microspectophotometrically measured in 70 patients with a gastric carcinoma lesion of less than 4.0 cm in diameter and with mucosal or minimal submucosal invasion. Two groups were prepared; low ploidy and high ploidy, according to the degree of dispersion on the DNA histogram. Twenty-four cases of high ploidy were reviewed from the aspects of clinicopathology and prognosis and the findings compared with data on 46 of low ploidy. The high ploidy group was characterized by an elevated lesion and a differentiated carcinoma while the low ploidy group had a depressed lesion and an undifferentiated carcinoma Postoperative recurrence was confirmed in none of the low ploidy cases and 2/24 of the high ploidy cases. The five and ten-year survival rates of the patients with high ploidy were 100 per cent and 91.1 per cent, respectively. Compared to the findings that patients with submucosal carcinoma of high ploidy survived at a rate of only 64.8 per cent in the 5-year follow-up, efforts should be directed toward a higher detection of gastric carcinoma with aneuploidy at the stage limited to within the intramucosal layer. Endoscopic treatment for early gastric carcinoma is not recommended, especially for a differentiated carcinoma, even if the invasion is confined to the mucosa, since it may include aneuploid carcinoma.

Adult↗
PubMed1985

Effects of catecholamines on myocardial viability in early reperfusion following hypothermic global ischemia in dogs--comparison between epinephrine and dobutamine.

Attempts were made to define the effects of epinephrine and dobutamine on the myocardium during early reperfusion for 60 minutes following hypothermic global ischemia at a myocardial temperature of 28 degrees C for 60 minutes under cardiopulmonary bypass. Ischemia was induced by cross-clamping the dog aorta. Epinephrine (0.1 microgram/kg/min) and dobutamine (5 micrograms/kg/min) were given throughout the reperfusion period by intravenous drip infusion, a control group was treated with saline infusion. Comparison of hemodynamic parameters was made before cardiopulmonary bypass, and at 30 and 60 minutes of reperfusion. Epinephrine and dobutamine significantly increased stroke volume index, left ventricular stroke work index and tissue calcium content compared with saline, however, myocardial water content was only slightly higher in the group given saline, compared with the other two groups. Myocardial mitochondrial membranes and cristae were slightly damaged and creatine phosphate content was reduced. Ultrastructural integrity was related to myocardial tissue calcium content, with a significant negative correlation. These results suggest that epinephrine (0.1 microgram/kg/min) will improve stroke volume index and left ventricular stroke work index, as does dobutamine (5 micrograms/kg/min), however, both agents had a minimal effect on reducing myocardial morphological and biochemical integrity, although catecholamines have detrimental effects on the myocardium in early reperfusion following ischemia.

Animals↗
PubMed1985

Sequential studies of rat urinary bladder epithelial lesions induced by ifosfamide (Z4942).

Urinary bladder damage caused by ifosfamide in male F344 rats was studied by light microscopy and scanning electron microscopy. Ifosfamide was injected intraperitoneally at doses of 30, 60 and 120 mg. per kg. body weight, and rats were killed at several intervals following treatment. The changes in the epithelium observed by light microscopy and scanning electron microscopy following ifosfamide injection were compared to those observed following cyclophosphamide injection. Necrosis and exfoliation of the urinary bladder epithelium occurred after day 1 of ifosfamide treatment and were followed by regenerative hyperplasia. This hyperplasia was reversible. A dose response was evident in the number and size of lesions induced and the time of regeneration and repair. Scanning electron microscopy disclosed short, uniform microvilli on the luminal surface of cells during the early phases of hyperplasia. These microvilli persisted for only 1 day, from days 1 to 7, and days 1 to 12 respectively, following injection of 30, 60 and 120 mg. per kg. of ifosfamide. The hyperplastic lesions also contained cells with pleomorphic microvilli and ropy or leafy microridges on their surfaces. These findings after ifosfamide administration were similar to those reported to be induced in the urinary bladder by cyclophosphamide.

Animals↗
PubMed1985

Molecular cloning and amino acid sequence of the precursor form of bovine adrenodoxin: evidence for a previously unidentified COOH-terminal peptide.

Several recombinant cDNA clones specific for the mitochondrial iron-sulfur protein adrenodoxin have been identified in a bovine adrenocortical cDNA library. One clone (pBAdx4) contains a 900-base-pair insert that includes the entire amino acid coding region of the adrenodoxin precursor protein. The amino acid sequence of mature adrenodoxin deduced from the nucleotide sequence of pBAdx4 is identical with that determined by protein sequencing except for three amide changes. The previously undetermined sequence of the adrenodoxin NH2-terminal precursor segment (58 amino acids) contains several basic residues, a characteristic feature of the precursor segment of proteins destined for mitochondria. In addition, a 14 amino acid extension is present at the COOH terminus of the mature adrenodoxin sequence. Whether this represents a COOH-terminal precursor segment is not clear. Three different adrenodoxin mRNAs are present [1.75, 1.4, and 0.95 kilobase(s) long] in bovine adrenocortical RNA. RNA from bovine corpus luteum, liver, and kidney contains transcripts that hybridize to adrenodoxin cDNA. Accumulation of adrenodoxin mRNA occurs in cultured bovine adrenocortical cells after treatment with ACTH or dibutyryl-cAMP, similar to that observed for the mitochondrial steroid hydroxylases that it services--namely, the cholesterol side-chain-cleavage cytochrome P-450 and the steroid 11 beta-hydroxylase cytochrome P-450.

Adrenal Cortex↗
PubMed1985

Postmortem functional changes in coronary and cerebral arteries from humans and monkeys.

Contractile responses to 30 mmol . litre-1 K+ of helical strips of coronary arteries from human cadavers did not change within 5 h after death; however, they were suppressed 8 h after death. In coronary arteries from monkey cadavers, the K+-induced contractions did not significantly differ within the first 5 h, but were suppressed 12 h after death. On the other hand, K+-induced contractions were retained without deterioration in cerebral artery strips from human cadavers 20 to 24 h after death and those from monkey cadavers 8 to 16 h. Acetylcholine caused contractions of human coronary arteries, but caused only a relaxation of monkey coronaries which was abolished by rubbing off the endothelium. These responses were attenuated by no more than K+-induced contractions up to 12 h after death. Maximum contractions induced by noradrenaline, histamine and serotonin remained the same in human coronary arteries for 3 to 5 h after death. Similar magnitudes of contraction were elicited by noradrenaline in human cerebral arteries up to 20 h after death. It appears that the reactivity of human coronary arteries to K+ and other vasoconstrictor agents used is normally retained for at least 6 h after death and that of human cerebral arteries up to 24 h.

Adolescent↗
PubMed1985

Vascular neuroeffector function in two-kidney, one clip hypertensive dogs.

In control dogs and those made hypertensive for 1 and 8 months by partially occluding a renal artery, contractile responses of mesenteric artery strips to adrenergic nerve stimulation and to norepinephrine, plasma renin activity and vascular angiotensin converting enzyme (ACE) activity were compared. Contractile responses to norepinephrine were potentiated in the artery strips from 8-month-hypertensive dogs; however, the response to electrical stimulation of adrenergic nerves was not influenced. Contractions induced by the nerve stimulation were potentiated by a low concentration (2 X 10(-10) mol/l) of angiotensin (ANG) II; the potentiating effect was enhanced in 8-month-hypertensive dog arteries. 3H-overflow evoked by adrenergic nerve stimulation was increased by ANG II to a greater extent in superfused mesenteric artery strips obtained from hypertensive (8-month) dogs, previously soaked in 3H-norepinephrine. Angiotensin converting enzyme activity was markedly greater in 8-month-hypertensive dog mesenteric arteries than in normotensive dog arteries. It may be concluded that the hypertension is maintained by increased sensitivity of post-synaptic alpha 1-adrenoceptors and pre-synaptic ANG receptors and increased vascular ACE activity, possibly promoting the production of ANG II in the vascular wall.

Adrenergic Fibers↗
PubMed1985

[Effect of danazol on serum prolactin and cortisol levels].

In order to investigate the effect of Danazol (D) on serum prolactin (PRL) and cortisol levels, D was given orally in a daily dose of 400 mg for 2 weeks to 4 women (400 mg group) and 600 mg to 5 women (600 mg group) at one month and more after menopause and oophorectomy. The blood samples were taken through an indwelling catheter into the cubital vein every 20 minutes for 2 hours before and after the administration of D. Serum hormone levels were determined by each specific RIA. In a comparison in each individual of mean hormone levels of 7 serum samples before and after D, (1) serum PRL levels were significantly lowered in 2 women after D of 400 mg (p less than 0.001) and in one woman after D of 600 mg (p less than 0.001), but increased in one woman after D of 600 mg (p less than 0.001), (2) serum cortisol levels were significantly lowered in one woman after D of 400 mg (p less than 0.01) and in 4 women after D of 600 mg (p less than 0.001). When the mean hormone levels in the 400 and 600 mg group (an average of the mean hormone levels of 7 samples in each group) were compared before and after D, (1) the mean serum PRL levels were not significantly affected by D in either group, (2) the mean serum cortisol levels were significantly lowered by D in the 600 mg group, but not in the 400 mg group. The present study demonstrated that serum PRL levels were not consistently affected by D in the condition without ovarian hormones, and serum cortisol levels were lowered after a relatively larger dose of D.

Aged↗
PubMed1985

[The inhibitory effect of peptic ulceration on the growth of early gastric cancer].

The correlation between the growth pattern and peptic ulceration occurring in the cancer lesion was studied in early gastric cancer. Although the superficially spreading type (Super), which grows slowly, showed a high rate of being accompanied by peptic ulceration (74.0%), the deeply penetrating type (Pen), with rapid growth, had a lower such rate (Pen A- expansive type 9.7%; Pen B- infiltrative type 16.1%). Deep ulceration accompanied 32% of the Super cases, 12% of the small mucosal cases and no cases of the Pen type. The Super and small mucosal types located at the intermediate gland area had peptic ulceration more frequently than those at the other areas. The rate of the cases of peptic ulceration of undifferentiated adenocarcinoma was high in the Super and small mucosal types, and that of differentiated adenocarcinoma was 64.0% in the Super and only 33.3% in the small mucosal type. This study clarified that the growth of early gastric cancer was inhibitively influenced by peptic ulceration, which was modified by the localization and histologic type of the carcinoma.

Adenocarcinoma↗
PubMed1985

[Evaluation of splenectomy in total gastrectomy for gastric cancer].

It has been well accepted that extensive prophylactic lymphadenectomy is certainly effective for elevating cure rate after gastric cancer surgery, however, regarding to the prophylactic splenectomy the arguments are controversial. We studied the value of splenectomy in total gastrectomy for gastric cancer by examining the late survival rates, the accuracy of intraoperative judgement of splenic hilar lymph node metastasis and postoperative changes of serum immunosuppressive factors. In curatively resected stage III cases without splenic hilar lymph node metastasis, the nonsplenectomized group showed a significant better late survival rate than the splenectomized group, 5-year survival rate being 59.9% in the former and 30.8% in the latter. In cases with splenic hilar lymph node metastases, 2 of 9 splenectomized patients survived more than 10 years. In cases of noncuratively resection, splenectomy did not enhance the survival rate. Although further clinical randomized study is needed to draw a definitive conclusion, we had better take a splenic reserve operation for the patients without splenic hilar lymph node metastasis. On the other hand, splenectomy should be performed in cases with splenic hilar lymph node metastases.

Gastrectomy↗