Search PubMed⌕ Search

Biomedical subjects

S Nishida

Publications and source records attributed to S Nishida.

At least 199 records · Page 11Linked to original sources
PubMed1997

Chronologic changes in the clinicopathologic findings and survival of gastric cancer patients.

PURPOSE: To determine the chronologic changes in the clinicopathologic features of gastric cancer patients. PATIENTS AND METHODS: The clinicopathologic findings of 1,795 patients with gastric cancer were examined retrospectively from hospital records obtained between 1969 and 1995. The patients were divided into three generations on the basis of chronologic order. The first generation included patients treated over the period 1969 to 1977; the second generation, 1978 to 1986; and the third generation, 1987 to 1995. RESULTS: The chronologic changes in the clinicopathologic findings for all gastric cancers included increases in the superficial type based on macroscopic appearance (P < .005), small-sized tumor (P < .025), superficial depth of invasion (P < .005), and earlier histologic stages (P < .005), in addition to a decrease in lymph node metastasis (P < .005). Overall, the postoperative survival rate has improved over time in gastric cancer patients, with 5-year survival rates of 36.0%, 53.3%, and 68.6% in the first, second, and third generations, respectively. In stages 1,2, and 3, the survival rate in the third generation was the highest of the three generations, whereas in stage 4, the survival rate did not differ between the three generations. Patients who underwent a D2 dissection showed a higher survival rate than those with D1 or D3 dissections, but there was no statistical difference in the survival of patients with D1, D2, and D3 dissections when stage 4 patients were excluded. CONCLUSION: The chronologic changes in gastric cancer patients over the past 27 years have included an increase in the incidence of earlier-staged gastric cancers, which has had a significant impact on the improved postoperative survival rate.

Adult↗
PubMed1997

Diagnosis of quinolone-induced arthropathy in juvenile dogs by use of magnetic resonance (MR) imaging.

The present study was carried out to confirm whether arthropathy in juvenile dogs induced by ofloxacin, a new quinolone antibacterial agent, may be diagnosed by magnetic resonance (MR) imaging. Three-month-old male beagle dogs were orally administered ofloxacin at 20 mg/kg once daily for 7 consecutive days. On day 8, MR images were obtained with a 4.7-tesla (T) super-conductive high magnetic field strength unit. An irregular cartilage surface and dissecans changes in the distal femoral condyle were observed. These MR findings were essentially consistent with pathologic observation showing multifocal blisters on the articular cartilage with an increased amount of turbid synovial fluid in the joint. The results demonstrate that occurrence of ofloxacin arthropathy in juvenile dogs can be clearly diagnosed by use of MR imaging.

Administration, Oral↗
PubMed1996

Diltiazem inhibits naloxone-precipitated and spontaneous morphine withdrawal in rats.

The effects of diltiazem, a Ca2+ channel blocker, on naloxone-precipitated and spontaneous morphine withdrawal were studied in male Sprague-Dawley rats. In naloxone-precipitated withdrawal, body weight loss and plasma corticosterone elevation were dose dependently inhibited by diltiazem injected 4 or 2 and 4 h before naloxone, respectively. Three administrations of diltiazem (17, 11 and 5 h before naloxone) did not reduce the above withdrawal signs. Diarrhea was dose dependently inhibited by all schedule of diltiazem treatments. In spontaneous withdrawal, body weight loss and plasma corticosterone elevation were dose dependently inhibited by two (6 and 12 h) or three (6, 12 and 18 h after the last morphine) treatments with diltiazem at 6-h intervals after the last morphine, but not by a single diltiazem injected 18 h after the last morphine.

Animals↗
PubMed1996

Inhibition assay for the binding of biotinylated von Willebrand factor to platelet-bound microtiter wells in the presence of ristocetin or botrocetin.

We developed a solid-phase inhibition assay for the binding of biotinylated von Willebrand factor (vWF) to platelet glycoprotein (GP)Ib based on an enzyme-linked immunosorbent assay (ELISA) with platelet-bound microtiter wells. Washed platelets were immobilized onto the microplates via the anti-GPIIb/IIIa monoclonal antibody (mAb) VNR-5. In the presence of an antibiotic ristocetin (1 mg/ml, final) or the snake venom botrocetin (2 micrograms/ml, final), biotinylated vWF bound to the affixed platelets with half-maximal binding occurring at a vWF concentration of approximately 2 micrograms/ml. Several specific inhibitors of the binding of vWF to GPIb abolished the interaction of biotinylated vWF with GPIb in a dose-dependent fashion, with comparable protein concentrations to those seen in the liquid-phase inhibition assay using 125I-vWF. These inhibitors included mAb against vWF (NMC-4), mAb against GPIb (AP-1), and two vWF fragments containing vWF's putative GPIb-binding domain, namely a 39/34-kDa dispase-digested vWF fragment and a recombinant vWF fragment. Thus, this new assay is a convenient alternative to the conventional inhibition assay using 125I-vWF.

Anti-Bacterial Agents↗
PubMed1996

Maintaining bone mass by bisphosphonate incadronate disodium (YM175) sequential treatment after discontinuation of intermittent human parathyroid hormone (1-34) administration in ovariectomized rats.

Intermittent treatment with human parathyroid hormone (1-34) [hPTH(1-34)] stimulates bone formation and increases cancellous bone mass in ovariectomized (OVX) rats. But PTH-induced cancellous bone rapidly disappears upon cessation of treatment. The fate of cortical bone treated by PTH has not been well characterized. Incadronate disodium (disodium cycloheptylaminomethylenedisphosphonate monohydrate, YM175) was expected to be antiresorptive without inhibiting bone formation. The purposes of this study were to determine (1) whether PTH treatment increases new cancellous and cortical bone mass and bone formation, (2) whether the new bone could be maintained by YM175 sequential treatment, and (3) whether the maintenance effect is persistent after YM175 withdrawal. Eighty-eight 11-week-old Sprague-Dawley rats were divided into sham operation and OVX groups. The OVX rats were treated for 8 weeks with the subcutaneous intermittent injection of 30 micrograms/kg of hPTH(1-34) three times a week beginning 4 weeks after surgery, then PTH treatment was withdrawn and YM175 (10 micrograms/kg) was injected subcutaneously three times a week for 4 weeks. YM175 treatment was withdrawn for the last 8 weeks of the protocol. The results of microstructural assessment in proximal tibial metaphysis and bone mineral density in distal and proximal femur demonstrated that PTH treatment for 8 weeks restored bone mass to the sham control level. However, after cessation of PTH treatment, the PTH-induced tibial cancellous bone mass showed a decrease at 4 weeks and almost totally disappeared after 12 weeks. Conversely, YM175 treatment maintained the PTH-induced tibial cancellous bone mass, and the bone continued to be maintained after 8 weeks of withdrawal of the YM175. Cortical bone was not lost during PTH treatment. YM175 maintained the PTH-induced new tibial cancellous bone in OVX rats by suppressing remodeling.

Animals↗
PubMed1996

Effects of a synthetic vitamin D analog, ED-71, on bone dynamics and strength in cancellous and cortical bone in prednisolone-treated rats.

To determine the action of corticosteroid on bone metabolism and assess the effects of a synthetic vitamin D analog, ED-71, on them, 56 SD rats, 8 weeks of age, were assigned to seven groups of eight animals each. Group 1 was the basal control. Group 2 was the nontreated control. Groups 3-7 were given prednisolone at 30 mg/kg of body weight (BW) twice a week and concomitantly administered ED-71 with respective doses of 0, 0.0125, 0.025, 0.05, and 0.1 micrograms/kg of BW for 12 weeks. In group 3, urinary calcium (U-Ca) and deoxypyridinoline (U-Dpy) were significantly increased compared with group 2. In groups 4-7, U-Ca values were increased but U-Dpy values were dose-dependently decreased. Age-dependent increases in the parameter values of BMD, compressive strength, trabecular bone volume (BV/TV), and trabecular thickness (Tb.Th) of the lumbar body were significantly suppressed in group 3 but dose-dependently increased in groups 4-7, and the values of group 7 exceeded those of group 2. The parameters of bone mineral density (BMD) and the bending strength of the femur in groups 4-7 were larger than the values in group 3 but did not reach the levels of group 2. The trabecular bone formation rate (BFR/BS) of the lumbar body measured by calcein labeling in group 3 was reduced when compared with group 2, but the values were not further decreased in groups 4-7. The perimeter ratios of double labels over single labels (dLS/sLS) greatly decreased by prednisolone, were dose-dependently increased to the level of the normal control by ED-71. Double-labeled perimeters and the dLS/sLS ratios were also increased in the periosteal envelope of the midfemur. These findings clearly demonstrate that prednisolone administration affects the age-related changes in bone metabolism, and ED-71 administration counteracts the effects by increasing intestinal calcium absorption, reducing bone resorption, and enhancing mineralization. The action of ED-71, however, seems to be less potent in the cortical bone.

Absorptiometry, Photon↗
PubMed1996

Contrast sensitivity of the motion system.

A number of experiments were conducted to investigate how global-motion performance varies with luminance contrast. When all the dots in the stimulus were the same contrast, performance improved with increasing contrast up to about the 15% level (Experiment 1). Increasing the contrast beyond this level had no additional effect on performance. When the contrast of a subgroup of the dots was varied, differential effects on performance could be obtained for contrasts up to the 80% level (Experiment 2). These results are interpreted as indicating that the performance saturation observed in Experiment 1 was due to the attainment of a performance ceiling at the global-motion level, and not due to contrast-response saturation of the underlying local-motion detectors. The results of earlier studies that have apparently found conflicting results (saturation vs no saturation) are discussed in light of the present results.

Contrast Sensitivity↗
PubMed1996

Bone marrow capacity for bone cells and trabecular bone turnover in immobilized tibia after sciatic neurectomy in mice.

Trabecular bone turnover and bone marrow capacity for the development of bone cells in the tibia were assessed after sciatic neurectomy (NX) in mice. The right hindlimbs of 6-week-old DDY mice were neurectomized and left hindlimbs were sham-operated and served as NX controls. Histomorphometrical analyses of the trabecular bone of the proximal tibia demonstrated the initial decrease in bone formation rate for the first 14 days and the subsequent increase in osteoclast surface for the next 14 days. The number of adherent stromal cells per tibia obtained for the NX limbs was reduced on days 7 and 10 postsurgically, and then recovered on day 12. However, the alkaline phosphatase activity of the cells was persistently depressed. The formation of osteoclast-like multinucleated cells in the marrow cultures obtained from NX limbs at days 10, 12, and 14 showed a significant increase in the medium containing parathyroid hormone (PTH). The number of colonies cultured for colony forming units-fibroblastic (CFU-f) that developed from the marrow cells did not differ in the NX and the contralateral limbs at any time during the period. On the other hand, the number of colonies cultured of colony forming units for granulocytes and macrophages (CFU-GM) was markedly increased for both the NX and the contralateral tibiae at days 12 and 14. This study clearly demonstrates that there are two stages in the development of osteopenia after NX. During the first 14 days, trabecular bone formation and number of marrow stromal cells are reduced. In the second 14 day period, the trabecular osteoclast number is increased and osteoclast formation from the bone marrow cells is enhanced in the presence of PTH. However, neither the CFU-f nor the CFU-GM assay could identify the changes in osteogenic or osteoclastogenic potential of the bone marrow. These in vitro assays provide limited information on the shifts in bone marrow cell lineages and the local environment producing osteopenia in the immobilized limb in vivo.

Alkaline Phosphatase↗
PubMed1996

Increase of preproenkephalin mRNA in the caudal part of periaqueductal gray by morphine withdrawal in rats: a quantitative in situ hybridization study.

Effects of morphine withdrawal on the levels of preproenkephalin (PPE) mRNA in the area from lateral to ventrolateral periaqueductal gray (PAG) were studied in rats by quantitative in situ hybridization. PPE mRNA in the rostral PAG was decreased by naloxone-precipitated morphine withdrawal but not affected by spontaneous morphine withdrawal. PPE mRNA in the caudal PAG was increased by both spontaneous and naloxone-precipitated morphine withdrawal.

Animals↗
PubMed1996

Effects of calcium channel blockers on steroidogenesis stimulated by ACTH and cAMP in isolated rat adrenal cells.

The effects of the calcium channel blockers verapamil, diltiazem, prenylamine and nifedipine on the ACTH- and cAMP-mediated pathway for steroidogenesis in a suspension solution of isolated rat adrenal cells were studied. Steroidogenesis stimulated by ACTH (10(-10) M) or cAMP (10(-3) M) was not inhibited by nifedipine (10(-4) M), but was strongly inhibited in a concentration-dependent manner by verapamil, diltiazem and prenylamine (10(-5) to 10(-4) M).

Adrenal Glands↗
PubMed1996

Illusory line motion in visual search: attentional facilitation or apparent motion?

A line, presented instantaneously, is perceived to be drawn from one end when a dot is flashed at that end prior to the presentation of the line. Although this phenomenon, called illusory line motion, has been attributed to accelerated processing at the locus of attention, preattentive (stimulus-driven) motion mechanisms might also contribute to the line-motion sensation. We tested this possibility in an odd-target-search task. The stimulus display consisted of two, four, or eight pairs of dots and lines. All lines were presented on the same side of the dots (eg right), except for the target line, which was presented on the opposite side (left). Subjects were asked to report the presence or absence of the target, which was presented in half of the trials. Low error rates for target detection (about 10%) even when the display consisted of eight dot-line pairs (ie display size was eight) indicated that illusory line motion could be perceived simultaneously at many locations. The interstimulus interval (ISI) between the dots and lines (0-2176 ms) and the contrast polarity (both dots and lines were brighter than the background, or dots were darker and lines were brighter) were also manipulated. When an ISI of a few hundred milliseconds was inserted, target detection was nearly impossible with larger display sizes. When the contrast polarity was changed, the target-detection performance was impaired significantly, even with no ISI. Moreover, it was found that the effects of display size, ISI, and contrast polarity were comparable in searches for a two-dot apparent-motion target. These results support the idea that preattentive, apparent-motion mechanisms, as well as attentional mechanisms, contribute to illusory line motion.

Attention↗
PubMed1996

Possible involvement of the total amount of morphine infused in the development of acute morphine dependence in rats.

The severity of naloxone-precipitated withdrawal in rats infused intravenously with morphine at the rates of 2.5, 5 and 10 mg/kg/hr over various time periods was investigated. Plasma morphine concentration reached a constant and rate-dependent level at 1 hr after the start of morphine infusion, and this level was maintained until the termination of infusion. Naloxone (2.0 mg/kg, s.c.) was challenged 18 hr after infusion was stopped, and the withdrawal was evaluated by plasma corticosterone (PCS) increase, diarrhea and body weight loss. The incidence of naloxone-precipitated withdrawal signs was related to both the infusion rate and duration of morphine infusion. The duration of morphine infusion (ET50) needed to elicit naloxone-precipitated PCS increase and diarrhea in 50% of the rats was inversely related to the morphine infusion rates, but the total amount of infused morphine (EA50) that elicited naloxone-precipitated withdrawals in 50% of rats was the same at all infusion rates. These results suggest that the total amount of morphine infused may play an important role in the development of acute physical dependence on morphine rendered by continuous intravenous morphine infusion for 1-8 hr.

Acute Disease↗
PubMed1996

[Sex differential in life expectancy at birth in Japan: (2) trends in sex differential in life expectancy at birth from 1920 to 1990].

Sex differentials in life expectancy at birth in Japan are analyzed for the period 1920 to 1990. The results show that there was a general increase in differences in mortality by sex over time. "The sex differential in age-specific death rate in 0-4 year age group (particularly age 0) explained most of the sex differential in life expectancy at birth before 1947. After 1950, the age group of 60-79 played a major role in the sex differential in life expectancy at birth. It is noteworthy that female mortality exceeded male mortality in age groups of 2-41 before 1930. Consequently, excess of female mortality reduced the sex differential in life expectancy at birth at that period. As for the sex differential in mortality rates by causes of death, tuberculosis, pregnancy and childbirth related disease exerted a great influence...before 1940. Recently, malignant neoplasms, heart diseases, cerebrovascular diseases, and accidents [have] become leading contributors to the sex differentials in life expectancy at birth." (SUMMARY IN ENG)

Age Factors↗
PubMed1995

cDNA cloning and deduced amino acid sequence of prothrombin activator (ecarin) from Kenyan Echis carinatus venom.

The complete amino acid sequence of ecarin is deduced from the nucleotide sequence of a cDNA clone isolated by screening a venomous gland cDNA library of Kenyan Echis carinatus. The cDNA sequence with 2379 base pairs encodes an open reading frame of 616 amino acids with a remarkable sequence homology to the putative precursor protein of trigramin from Trimeresurus gramineus venom (61% identity) and a large hemorrhagin, jararhagin, from the pit viper Bothrops jararaca venom (62% identity). Thus, ecarin, as well as jararhagin and trigramin, is translated as a precursor protein, which may be processed posttranslationally. The ecarin proprotein has a "cysteine switch" motif (-Pro-Lys-Met-Cys-Gly-Val-) similar to that involved in the activation of matrix metalloproteinase zymogens. The processed mature protein consists of 426 amino acid residues (residues 191-616), showing the strongest sequence similarity with that of Russell's viper venom factor X activator (RVV-X) heavy chain (64% identity). Like RVV-X heavy chain, ecarin contains metalloproteinase, disintegrin, and cysteine-rich domains. The metalloproteinase domain has a typical zinc-chelating sequence (-His-Glu-Xaa-Xaa-His-Xaa-Xaa-Gly-Xaa-Xaa-His-), as found in crayfish astacin. In the disintegrin domain of ecarin, the Arg-Gly-Asp sequence is replaced by Arg-Asp-Asp, as found in the disintegrin domains of RVV-X heavy chain (Arg-Asp-Glu) and a guinea pig sperm fusion protein, PH-30 beta (Thr-Asp-Glu). These findings show that while there are structural and evolutionary relationships among these proteins, each has a unique functional activity.

Amino Acid Sequence↗