Biomedical subjects

I Sugimoto

Publications and source records attributed to I Sugimoto.

At least 37 records · Page 2Linked to original sources

PubMed1998

The gain of the hepatorenal reflex in anesthetized dogs.

To determine the overall gain of the hepatorenal reflex, hypertonic NaCl solutions were infused into the portal vein or inferior vena cava of anesthetized dogs at a rate of 0.01 ml/kg/min for 30 min and the urinary Na excretion measured. Infusion of 2.25% NaCl into either the portal vein or inferior vena cava had no effect. Portal infusion of 4.5% or 9% NaCl produced an increase of 36 +/- 16 or 40 +/- 17 microeq/kg/30 min, respectively, while inferior vena caval infusion had no effect. With 13.5% NaCl infusion, a significant increase in the natriuretic response was seen with portal venous infusion, with no significant difference between portal venous and inferior vena caval infusion. Thus, the difference in the natriuretic response between portal venous and inferior vena caval infusion was dependent on the degree of input; when an appropriate input was given, natriuresis was induced only by portal venous infusion, probably mediated by the hepatorenal reflex. The gain of the hepatorenal reflex was calculated from the output divided by the input. When 4.5% or 9% NaCl was infused into the portal vein, the 2-h gain of the hepatorenal reflex was 0.38 +/- 0.15 or 0.34 +/- 0.14, respectively.

Animals↗

PubMed1998

Limb salvage and survival rates among elderly patients with advanced limb ischemia.

The purpose of this study was to clarify the incidence of limb salvage and patient survival rates among elderly patients with advanced leg ischemia. We reviewed the records of 159 patients treated for advanced ischemia over a 15-year period at Aichi Medical University, 74 of whom were aged over 75 years and 85, between 65 and 74 years. There was a collective total of 186 limbs; 82 in the older group and 104 in the younger group. The older group had a greater proportion of women, and a higher incidence of coronary heart disease, pulmonary dysfunction, and acute onset of advanced ischemia than the younger group. Limb salvage was achieved in 73% of the affected limbs in the older group and in 92% of the limbs in the younger group. The poor limb salvage rate in the older group was mainly related to the high initial amputation rate. Early recognition of the sentinel ischemic signs before the ischemia is essential, especially in the elderly. Timely revascularization should be attempted whenever possible, and it should not be abandoned simply because the patient is deemed too old. The 1-, 3-, and 5-year survival rates in the older group were 59%, 28%, and 23%, respectively, which were markedly poorer than the expected survival rates of the age- and sex-matched Japanese population at 1, 3, and 5 years, which were 93%, 79%, and 65%, respectively. Thus, advanced limb ischemia carries a poor prognosis to the point of being life-threatening, and further continuous systemic management with the collaboration of physicians and surgeons must be provided even after the patient has left the hospital.

Aged↗

PubMed1998

Down-regulation of protein kinase C-alpha detected in human colorectal cancer.

The down-regulation of protein kinase C (PKC) was examined by Western blot procedure on about 30 tissue samples derived from human colorectal cancer and the corresponding normal mucosa. PKC-alpha down-regulation was detected in 60% of the cancer tissues compared with the respective normal mucosa and was observed in a higher frequency with the tissues under more advanced cancer stages. However, the frequencies of the down-regulation of PKC-delta and PKC-zeta were lower than that of PKC-alpha. These results suggest that a decreased level of PKC-alpha may affect the cell growth and tumor promotion in colorectal tissue.

Colorectal Neoplasms↗

PubMed1998

Possible role of alteration in pH, but not in ionic strength, in the modulation of Ca(2+)-dependent and diacylglycerol-induced association of protein kinase C-alpha with plasma membrane.

In an attempt to elucidate the mechanism of the membrane binding of protein kinase C-alpha (PKC-alpha), effects of pH and ionic strength were examined on Ca(2+)-dependent and diacylglycerol-induced association of this PKC with rat liver plasma membrane. In the absence of diacylglycerol, the membrane-bound PKC-alpha increased according to the changes in pH from 6 to 8. However, these reactions were not seriously influenced by alterations in ionic strength (0-240 mM NaCl). In the presence of diacylglycerol, this pH-modulated binding of PKC-alpha to plasma membrane was more effective under lower Ca2+ concentration at pH 8. These results suggest that alkaline pH conditions seem to be important for preferable association of PKC-alpha with plasma membrane.

Amino Acid Sequence↗

PubMed1998

Suppression of renal sympathetic nerve activity during portal vein infusion of hypertonic saline.

Sodium ions absorbed from the intestine are postulated to act on the liver to reflexly suppress renal sympathetic nerve activity (RSNA), resulting in inhibition of sodium reabsorption in the kidney. To test the hypothesis that the renal sympathoinhibitory response to portal venous NaCl infusion involves an action of arginine vasopressin (AVP) at the area postrema, we examined the effects of portal venous infusion of hypertonic NaCl on RSNA before and after lesioning of the area postrema (APL) or after pretreatment with an AVP V1 receptor antagonist (AVPX). Rabbits were chronically instrumented with portal and femoral venous catheters, femoral arterial catheters, and renal nerve electrodes. Portal venous infusion of 9.0% NaCl (0.02, 0.05, 0.10, and 0.15 ml.kg-1.min-1 of 9.0% NaCl for 10 min) produced a dose-dependent suppression of RSNA (-12 +/- 3, -34 +/- 3, -62 +/- 5, and 80 +/- 2%, respectively) that was greater than that produced by femoral vein infusion of 9.0% NaCl (2 +/- 3, -3 +/- 2, -12 +/- 4, and -33 +/- 3%, respectively). The suppression of RSNA produced by portal vein infusion of 9.0% NaCl was partially reversed by pretreatment with AVPX (-9 +/- 3, -20 +/- 3, -41 +/- 4, and -55 +/- 4%, respectively) and by APL (-11 +/- 2, -25 +/- 2, -49 +/- 3, and -59 +/- 6%, respectively). There were no significant differences between the effects of AVPX and APL, and the effect of APL was not augmented by AVPX. These results indicate that the suppression of RSNA due to portal venous infusion of 9.0% NaCl involves an action of AVP via the area postrema.

Animals↗

PubMed1998

Chylous reflux into the lower limb with septic shock successfully treated by resection of the retroperitoneal megalymphatics.

A 15-year-old boy with primary chylous reflux into the left lower limb with septic shock was successfully treated by en bloc resection and ligation of the retroperitoneal megalymphatics. The episode of chyle discharge from the lower limb and/or genitalia and the presence of small vesicles of the skin may be an important sign in diagnosing chylous reflux. Surgical interruption of the chylous reflux and reduction of girth may be needed.

Adolescent↗

PubMed1997

A new surgical technique for the treatment of life-threatening congenital arteriovenous malformation--intraluminal graft implantation.

A new surgical intraluminal graft implantation technique was undertaken in a 27-year-old man with a massive, life-threatening, high-flow congenital arteriovenous malformation (AVM) involving the left lower extremity, which was resistant to such challenges as transarterial embolizations or partial resections. For occlusion of the feeder branches, a composite graft composed of two grafts with different diameters, which matched to the arterial lumen, was surgically inserted into the superficial femoral artery. The implanted graft occluded 2 weeks after the insertion. Although amputation distal to the knee was necessary because of the foot necrosis, the graft was useful in reducing the cardiac output (from 14.3 l/min to 9.8 l/min) and obviating hip joint amputation. A further clinical study is necessary to examine whether or not it is an acceptable treatment modality.

Adult↗

PubMed1996

Tacalcitol (1,24(OH)2D3, TV-02) inhibits phorbol ester-induced epidermal proliferation and cutaneous inflammation, and induces epidermal differentiation in mice.

In this study, we examined the cutaneous effects of tacalcitol [1,24(R)(OH)2D3] on epidermal proliferation, differentiation, and skin inflammation in vivo using hairless mice. Tacalcitol was shown to inhibit epidermal proliferation using TPA-induced ornithine decarboxylase activity and DNA synthesis as indices, and the induction of epidermal differentiation using type I transglutaminase activity as an index. Tacalcitol also displayed an antiinflammatory effect on TPA-induced inflammatory changes histopathologically. These results confirm the clinical efficacy of tacalcitol in psoriasis, and suggest that it may be efficacious in the treatment of other inflammatory skin diseases.

Administration, Topical↗

PubMed1996

Decreased bone mineral density associated with early menopause progresses for at least ten years: cross-sectional comparisons between early and normal menopausal women.

To establish whether early onset of menopause carries an increased risk of osteoporosis, we compared the bone mineral density (BMD) of the second to fourth lumbar vertebrae (L2-4) between 18 women who had menopause before 43 years of age (early menopause group) and 19 women who had menopause after reaching 43 years of age (normal menopause group). Serum levels of calcium, phosphorus, calcitonin, intact parathyroid hormone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E2), and alkaline phosphatase activity were measured, and urine samples were analyzed to derive calcium/creatinine, hydroxyproline/creatinine, pyridinoline/creatinine, and deoxypyridinoline/creatinine (D-Pyr/Cr) ratios. Mean BMD was significantly lower in the early menopause group than in the normal menopause group, and individual BMD values in about half of the subjects in the former group were below the fracture threshold for Japanese women. Serum concentrations of LH, FSH, and E2 were slightly, but not significantly, lower in the early menopause group than in the normal menopause group. The D-Pyr/Cr ratio was significantly higher in the early menopause group than in the normal menopause group. There was no correlation between L2-4 BMD and age or the number of years after menopause in the normal menopause group, but both age and the number of years after menopause were negatively correlated with L2-4 BMD in the early menopause group. These results indicate that BMD in women who have early menopause continues to decline for up to 10 years, and that menopause and aging increase the risk of osteoporosis.

Adult↗

PubMed1996

The effect of 1,24(R)(OH)2D3 cream and ointment on epidermal proliferation and differentiation in mice.

BACKGROUND: The 1,24(R)(OH)2D3 (tacalcitol) ointment (2 micrograms/g) is available commercially as an antipsoriatic drug in Japan, but the cream preparation of tacalcitol is still under development. OBJECTIVE: This study was conducted to compare the ability of tacalcitol cream and ointment to inhibit epidermal proliferation and induce epidermal differentiation. METHODS: We measured the ornithine decarboxylase activity and type I transglutaminase activity as indices of proliferation and differentiation, respectively, in hairless mice. RESULTS: These effects were statistically equal to those of the ointment preparation at the same dose, 2 micrograms/g, without inducing hypercalcemia. CONCLUSIONS: These findings suggest that topical application of 1,24(OH)2D3 cream (2 micrograms/g) might have the same potency as the ointment formulation in the treatment of psoriasis.

Administration, Topical↗

PubMed1995

Benefits of arterial reconstruction in claudication.

We conducted a midterm follow-up of 150 claudicants who underwent surgical reconstruction by assessing cumulative patency, survival, and palliation (graft patency in live patients) rates. Eighty-nine claudicants (group I) underwent direct (in situ) proximal revascularization, 33 (group II) had indirect (ex situ) proximal revascularization, while 28 (group III) had distal revascularization. The secondary patency rates at 3 years were 97.5% in group I, 97.0% in group II, and 75.0% in group III, respectively. Only one patient with limb graft thrombosis required below-knee amputation. There were 3 perioperative deaths (2 in group I and 1 in group II). The survival rates at 3 years were 86.0% in group I, 69.5% in group II, and 95.8% in group III, respectively. The palliation rates at 3 years were 84.8% in group I, 70.0% in group II, and 77.9% in group III, respectively. These findings indicate the midterm benefits of supra- and infrainguinal arterial reconstructions, and also suggest that the preoperative assessment of risks in individual patients, the selection of the appropriate operative procedure and graft material, and intensive postoperative follow-up and management of any associated disease are all important aspects in the treatment of claudicants.

Aged↗

PubMed1994

Alendronate modulates osteogenesis of human osteoblastic cells in vitro.

The bisphosphonates, which are carbon-substituted pyrophosphates, have been studied extensively both in vivo and in vitro to elucidate their effects on bone tissues and cells. However, because these agents were shown to have a potent inhibitory effect on bone resorption, the majority of studies have focused on only this aspect of bone metabolism. There appears to be less information regarding the direct effect of bisphosphonates on bone formation, so thus we undertook experiments to investigate the effects of bisphosphonates, especially alendronate, on the mineralization and matrix protein synthesis of human osteoblastic cells in vitro. The data show that the bisphosphonates, alendronate, etidronate and pamidronate, suppressed 1,25-dihydroxycholecalciferol (1,25(OH)2D3)-stimulated mineralization of human osteoblastic cells at high concentrations, while relatively lower concentrations of alendronate and etidronate potentiated mineralization of the cells in the presence of 1,25(OH)2D3. The potentiation of mineralization with alendronate was accompanied by increased synthesis of bone matrix proteins, osteocalcin and collagen, and the mRNA of pro alpha(I) collagen. These findings show that in addition to their well-known effects on bone resorption, bisphosphonates have significant and direct effects on osteogenesis in osteoblasts in vitro. The actual mechanism remains to be further investigated.

Alendronate↗

PubMed1994

Recurrence of cystic adventitial disease in an interposed vein graft.

A case of cystic adventitial disease (CAD) of the popliteal artery with intermittent claudication in the left calf is reported. This patient was first treated by total excision of the cyst and the involved artery followed by graft interposition with an autogenous saphenous vein. Recurrence of CAD in the interposed vein graft was noted after 6 months, and excision of the cyst with the involved graft and graft interposition with an autogenous saphenous vein was again required. We consider that the definitive evidence from early recurrence in the interposed vein graft shown in this case will close the discussion of the cause of CAD. The cystic lesion is thought by some to originate from the adventitia; traumatic, embryologic, or systemic abnormality theories were proposed. We assume that the mucin-secreting synovial cells originating from the neighboring joint capsule, tendon sheath, or, in some cases, from the ganglion itself, directly invade the adventitia through any rough or injured crack caused by trauma to the adventitia or simply attach to and encircle the adventitia. Total resection of the lesion with grafting is the recommended treatment for CAD because of the excellent results. However, as shown in our case, complete removal of the synovial cells even by resection technique may be difficult; therefore intensive follow-up is fundamentally necessary in this disease.

Adult↗

PubMed1994

[Forms of an in vivo polymerization product, n-butyl-2-cyanoacrylate, within the gastric wall].

The in vivo morphology of sclerosants, n-butyl-2-cyanoacrylate (Histoacryl; referred hereinafter to briefly as HA) polymer formed within the gastric wall was investigated in an animal experiment. The results indicate that HA polymer formed after local injection of HA into the stomach wall with deliberate avoidance of contact with blood got scattered in an arboroid pattern, suggesting thus that when HA is injected into the gastric mucosa at an extravascular site, the resulting polymer is likely to get scattered and miss the target site. Polymerization products that were formed after injection of HA alone were deep purple, dense, firm, rounded in shape and lesser in adverse histologic influence upon the walls of stomach. On the other hand, those formed by injection of HA with Lipiodol were large-sized, light brown and oval-shaped ones with more irregular margins and less distinct boundaries as compared to those seen after injection of HA alone. These results of the study led us to conclude that at the present time it would seem wise to limit the use of HA for this particular therapeutic purpose only to those cases of bleeding gastric varices.

Animals↗

PubMed1994

[Additional palliative operation and staged definitive operation for pulmonary atresia with intact ventricular septum].

Between 1981 and 1992, 38 consecutive patients underwent initial operation for pulmonary atresia with intact ventricular septum. Transpulmonary valvotomy using balloon occlusion of RV outflow was carried out in 24 patients at a mean age of 20 days. An additional Blalock-Taussig shunt was required in 4 patients early in the series. Based on a retrospective review on the patients early in the series, initial palliative procedure had been decided in conformity with the value of an index of RV development (RVDI) = RVEDV% x TVD% x RVODmm/BSAm2 x 10(-5), and recent 3 patients with RVDI < 0.35 and patent RV outflow underwent concomitant valvotomy and Blalock-Taussig shunt. Fourteen patients with muscular atresia of RV outflow or major sinusoidal coronary artery communication underwent Blalock-Taussig shunt. There were 1 operative and 3 late deaths and second Blalock-Taussig shunt was required in 6 patients. Definitive repair was carried out in 20 patients between 1985 and 1994. Fifteen patients with RVEDV > 30% of normal had biventricular repair (partial closure of ASD in 6) and 5 underwent Fontan type repair. In terms of the definitive procedures, when the RV.TV index (= RVEDV% x TVD% x 10(-4)) is greater than 0.4, complete repair should be performed. When the index is between 0.2 and 0.4, the atrial septal defect should only be partially closed when the outflow tract is reconstructed. In those cases with an index of less than 0.2, the Fontan procedure seems to be a procedure of choice.

Humans↗

PubMed1992

[Acute aortic dissection in a patient with Marfan's syndrome and severe pectus excavatum--emergency surgical repairs of ascending aortic dissection and aortic regurgitation complicated by pectus excavatum in Marfan's syndrome].

A case of acute aortic dissection Stanford Type A occurring in a patient with Marfan's syndrome, complicated with aortic regurgitation and severe pectus excavatum, is reported with successful surgical correction. The patient was a 33-year-old woman, who suffered from severe back pain riding to work. An emergency operation consisting of Cabrol's procedure for aortic dissection Stanford Type A and sternal turnover for pectus excavatum was performed simultaneously. Because of the postoperative mediastinal bleeding the implanted sterno-costal complex was removed on the second POD and the prosthetic sternum was reimplanted on the tenth POD. The two-stage operation seems preferable in such an emergency case to avoid postoperative bleeding and infection.

Acute Disease↗

PubMed1990

[A study on endoscopic hemostasis from the viewpoint of morphologic traits of Dieulafoy ulcer--an attempt at endoscopic hemostasis by local injection of aethoxysklerol and ethanol].

Characteristics of the vascular course of ruptured vessels in the submucosal layer of Dieulafoy ulcer were studied, and endoscopic hemostatic treatment was performed using Aethoxysklerol and ethanol. 1) Observations of vessel courses in serial sections revealed that ruptured vessels in Dieulafoy ulcer exhibit rhexis in the lateral portions of the vessel and long courses over the ulcer margin in the submucous layer. 2) More dependable hemostasis seemed to be provided by thrombosis not only at the source of bleeding. i.e., at the site of vessel rupture, but also in the region of the whole ruptured vessel in the submucous layer. 3) Hemostatic treatment by local injection of Aethoxysklerol and ethanol was performed in 4 patients with Dieulafoy ulcer, and complete hemostasis was achieved in all 4 patients.

Adult↗

PubMed1989

Quantitative analysis of trazodone hydrochloride in tablets by an ion-selective electrode.

A simple assay procedure for the quantitation of trazodone hydrochloride in tablets, without prior separation, has been developed using a trazodone-selective electrode. The electrode was based on a trazodone:tetrakis(p-chlorophenyl)borate ion-pair complex, dioctyl phthalate, and polyvinyl chloride matrix that were mounted on a PTFE membrane. The electrode showed a near-Nernstian response in the range of 10(-2) to 5 x 10(-6) M trazodone over the pH range of 2.5 to 5.0, with a cationic slope of 58 mV/concentration decade. The durability of the electrode and the reproducibility of the performance among the electrodes were sufficient. The electrode was used for the determination of the pKa value of trazodone. The selectivity of the electrode to a number of interferences was investigated. Many inorganic cations (alkali and alkaline earth metals) and pharmaceutical excipients did not interfere, but some organic ammonium compounds interfered according to their extractability. Determination of 10 to 3000 micrograms/mL of trazodone hydrochloride in aqueous solution showed an average recovery of 100.6% (mean standard deviation 0.4%) by direct potentiometry. This assay was applied to determine trazodone hydrochloride in tablets and the results compared favorably with those obtained by high-performance liquid chromatography.

Chromatography, High Pressure Liquid↗