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1.
Surg Endosc ; 33(6): 1769-1776, 2019 06.
Article in English | MEDLINE | ID: mdl-30291444

ABSTRACT

BACKGROUND: The number of colorectal cancer cases is increasing, and so the number of laparoscopic colectomy procedures being performed is also increasing, leading to an increased workload for surgeons. However, operating for prolonged time periods may cause surgeons to lose their concentration and develop fatigue. We hypothesized that there is a time-of-day variation in outcome for patients with colorectal cancer who undergo laparoscopic colectomy. The present study aimed to compare the operative outcome between laparoscopic colectomy for colorectal cancer performed in the morning versus the afternoon. METHODS: This was a single-center, retrospective study. All 1961 consecutive patients who underwent laparoscopic surgery for colorectal cancer between 2007 and 2017 were included; 1006 of these patients underwent morning surgery, while 955 underwent afternoon surgery. These patients were analyzed using propensity score matching, giving 791 patients in each group. The short- and long-term outcomes in both groups were compared. RESULTS: Before propensity score matching, the morning group had a larger mean tumor size than the afternoon group (30 cm vs 35 cm; P = 0.0035). After matching, the two groups did not significantly differ in any patient characteristics. Compared with the afternoon group, the morning group had a significantly lesser incidence of intra-operative organ injury (0.25% vs 1.13%; P = 0.027), and a significantly greater incidence of post-operative abdominal abscess (2.03% vs 0.75% P = 0.028). The incidences of other complications and morbidities were similar in both groups. The median operative time in the morning group (201 min) was significantly longer than that in the afternoon group (193 min; P = 0.0124). The two groups did not differ in 5-year overall survival rates and 5-year disease-free rates within any disease stage. CONCLUSIONS: Surgical start times are correlated with surgical outcomes. Our data will help to ensure the safest possible surgeries.


Subject(s)
Colorectal Neoplasms/surgery , Operative Time , Aged , Aged, 80 and over , Colectomy , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , Female , Humans , Incidence , Japan/epidemiology , Laparoscopy , Male , Middle Aged , Postoperative Complications/epidemiology , Propensity Score , Retrospective Studies , Survival Analysis
2.
Curr Oncol ; 24(4): e328-e332, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28874903

ABSTRACT

Despite progressive treatments with tandem stem-cell transplantation, patients with incurable myeloma eventually succumb to relapsed or refractory disease if left untreated. Promising agents such as proteasome inhibitors and immunomodulating imide drugs (imids), including the newer-generation agent pomalidomide, in combination with lower-dose dexamethasone, have been shown to be effective and to significantly improve and prolong survival in pretreated patients. Although the incidence of pomalidomide hypersensitivity reaction (hsr) in this class of drugs is not as well known, we have documented cutaneous toxicity (grade 3 by the Common Terminology Criteria for Adverse Events, version 4) in 2 separate cases (not yet published). Because the imids are chemically, structurally, and pharmacologically similar, it is not unreasonable to consider possible cross-reactivity in pomalidomide recipients who developed hsr when receiving previous lines of imids. As a patient's advocate, it is only prudent to provide a responsible, and yet practical, means to better address cross-sensitivity for patients. Intervention with the use of a rapid desensitization program (rdp) as a preventive measure should be introduced before initiating pomalidomide. Such a proactive measure for the patient's safety will ensure a smooth transition into pomalidomide treatment. A hsr can be either related or non-related to immunoglobulin E. As imids become an essential treatment backbone for myeloma and other plasma-cell diseases, an increasing number of patients could experience skin and other life-threatening toxicities, resulting in unnecessary discontinuation of these life-prolonging agents. An extemporaneously prepared pomalidomide suspension developed at our centre enables patients to undergo rdp safely. Patients enjoy a good quality of life and clinical response after the rdp procedure.

3.
Curr Oncol ; 23(4): e355-61, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27536184

ABSTRACT

BACKGROUND: Venous thromboembolism (vte) is a recognized complication in patients treated with asparaginase-containing chemotherapy regimens; the optimal preventive strategy is unclear. We assessed the safety and efficacy of prophylaxis using low-dose low molecular weight heparin in adult patients with acute lymphoblastic leukemia in complete remission treated with an asparaginase-based post-remission chemotherapy regimen. METHODS: As part of the intensification phase of the Dana-Farber Cancer Institute 91-01 regimen, asparaginase was administered weekly to 41 consecutive patients for 21-30 weeks; these patients also received prophylaxis with enoxaparin 40 mg daily (60 mg for patients ≥80 kg). Outcomes were assessed against outcomes in a comparable cohort of 99 patients who received the same chemotherapy regimen without anticoagulation prophylaxis. RESULTS: The overall rate of symptomatic venous thrombosis was not significantly different in the prophylaxis and non-prophylaxis cohorts (18.92% and 21.74% respectively). Among patients receiving prophylaxis, vte occurred in higher proportion in those who weighed at least 80 kg (42.86% vs. 4.35%, p = 0.0070). No major bleeding complications occurred in the prophylaxis group (minor bleeding: 8.1%). CONCLUSIONS: Prophylaxis with low-dose enoxaparin during the intensification phase was safe, but was not associated with a lower overall proportion of vte.

4.
Curr Oncol ; 22(5): e357-63, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26628876

ABSTRACT

BACKGROUND: Keratoconjunctivitis sicca from chronic graft-versus-host disease (cgvhd) after allogeneic stem cell transplantation is common, leading to severe corneal damage and blindness if not treated. We retrospectively examined the efficacy and safety of pooled human albumin eye drops (haeds) for symptom relief in 40 stem-cell transplantation patients after other alternatives had failed. METHODS: The Common Terminology Criteria for Adverse Events (version 4.0) and the cgvhd grading scale were used to compare response in the patients during January 2000 and July 2013. In addition, on days 1 and 30, the haeds were subjected to quality assurance testing for sterility, oncotic pressure, albumin measurement, viscosity, pH, and purity by protein electrophoresis. RESULTS: Use of haeds resulted in symptom relief for 37 patients (92.5%); 3 patients (7.5%) failed to improve with use of haeds (p ≤ 0.0001). Of the 37 patients having symptom relief, 7 (19%) improved from grade 3 to no dry eye symptoms. Proportionately, post-treatment symptom improvement by two grade levels, from 3 to 1 (70%), was significantly higher than improvement by one grade level, from 3 to 2 (11%) or from 2 to 1 (19%, p ≤ 0.0001). Time to symptom relief ranged from 2 weeks to 28 weeks. Of the 40 patients, 38 (95%) had no adverse reactions. Days 1 and 30 quality assurance testing results were equivalent. CONCLUSIONS: Complications of keratoconjunctivitis sicca were well managed and well tolerated with haeds when other remedies failed. Quality assurance testing confirmed that haeds were safe and stable in extreme conditions.

6.
Diabetes Obes Metab ; 9(3): 369-78, 2007 May.
Article in English | MEDLINE | ID: mdl-17391165

ABSTRACT

AIM: The aim of this study was to examine the mechanism by which a novel non-thiazolidinedione (TZD) peroxisome proliferator-activated receptor (PPAR) gamma agonist, FK614, ameliorates insulin resistance in Zucker fatty rats. METHODS: FK614 (1, 3.2 or 10 mg/kg) and a TZD PPARgamma agonist, pioglitazone (1, 3.2 or 10 mg/kg), were orally administered to Zucker fatty rats (genetically obese and insulin resistant) once a day for 14 days, and an oral glucose tolerance test was performed. The expression levels of various genes in the white adipose tissue (WAT) of Zucker fatty rats treated with FK614 (3.2 mg/kg), pioglitazone (10 mg/kg) and another TZD PPARgamma agonist, rosiglitazone (3.2 mg/kg), were determined using a real-time reverse transcription-polymerase chain reaction method. Morphometric analysis of the WAT of Zucker fatty rats treated with FK614 (3.2 mg/kg) and pioglitazone (10 mg/kg) was performed. Glucose transport activity in the isolated soleus muscle of FK614-treated Zucker fatty rats was also investigated. RESULTS: FK614 and pioglitazone both improved glucose tolerance in Zucker fatty rats. FK614 significantly increased the expression levels of acyl CoA oxidase, a PPAR-responsive gene, and adipocyte fatty acid-binding protein (aP2), an adipocyte differentiation marker gene, in epididymal WAT. It also significantly decreased the level of gene expression of tumour necrosis factor-alpha, an insulin resistance-inducing factor in retroperitoneal WAT, as did pioglitazone and rosiglitazone. FK614 and pioglitazone both significantly increased the total number of adipocytes and decreased their average size in WAT, mainly by increasing the number of small adipocytes. Additionally, administration of FK614 to Zucker fatty rats enhanced insulin sensitivity for glucose uptake in the soleus muscle. CONCLUSION: This study suggests the possibility that FK614 induces adipocyte differentiation in Zucker fatty rats by stimulating PPARgammain vivo, thereby changing the character of WAT and improving insulin sensitivity throughout the body.


Subject(s)
Benzimidazoles/administration & dosage , Hypoglycemic Agents/administration & dosage , Insulin Resistance/physiology , Obesity/metabolism , PPAR gamma/agonists , Acyl-CoA Oxidase/analysis , Adipocytes, White/drug effects , Adipose Tissue/metabolism , Administration, Oral , Animals , Biological Transport/drug effects , Cell Count , Cell Size/drug effects , Epididymis/metabolism , Fatty Acid-Binding Proteins/analysis , Gene Expression/drug effects , Glucose/metabolism , Glucose/pharmacokinetics , Glucose Tolerance Test/methods , Insulin Resistance/genetics , Male , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Pioglitazone , Rats , Rats, Zucker , Rosiglitazone , Thiazolidinediones/administration & dosage
7.
Biorheology ; 41(1): 45-52, 2004.
Article in English | MEDLINE | ID: mdl-14967889

ABSTRACT

In order to clarify the phase relationship between velocity pulse and pressure pulse propagating along microvessels, the red cell velocity and intravascular pressure were simultaneously measured in the rat pial arterioles of 41-53 microm in diameter with a high temporal resolution by a laser-Doppler anemometer and a servo-null micropressure system. It was found that the velocity pulse preceded the pressure pulse in all the measured arterioles by 18.7-35.6 ms. The corresponding phase difference was 43.6+/-6.9 degrees (mean +/- SD), which is not statistically different from 45 degrees. The value is consistent with the phase difference predicted for the blood flow in microvessels with a small reflection coefficient at frequencies as low as the heart rate of the rats. The present results suggest that the upstream changes in blood flow are transmitted by the velocity pulse faster than by the pressure pulse in the microvasculature.


Subject(s)
Brain/blood supply , Erythrocytes/physiology , Animals , Arterioles , Blood Flow Velocity/physiology , Blood Pressure/physiology , Laser-Doppler Flowmetry , Male , Pulsatile Flow , Rats
8.
Br J Nutr ; 90(6): 1031-8, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14641962

ABSTRACT

The prevention of arterial thrombotic diseases has a high priority in developed countries. An inappropriate diet may be an important risk factor for thrombotic events. The daily intake of an anti-thrombotic diet may offer a convenient and effective way of prevention. The aim of the present study was to test tomato extracts for anti-thrombotic effects and to identify those varieties that have such an effect. A shear-induced platelet-function test (haemostatometry) was used to test anti-thrombotic potential in vitro. Extracts from those tomato varieties that showed a significant anti-thrombotic activity in vitro were further assessed in vivo, using a laser-induced thrombosis test in mice. One tomato variety (KG99-4) showed significant anti-thrombotic activity both in vitro and in vivo. KG99-4 inhibited not only platelet-rich thrombus formation but also had a thrombolytic effect. It is concluded that haemostatometry can detect and classify the anti-thrombotic potential of fruits and vegetables and offers a simple way of screening for such effects.


Subject(s)
Diet , Solanum lycopersicum , Thrombosis/prevention & control , Animals , Blood Coagulation/drug effects , Fibrinolytic Agents/pharmacology , Hot Temperature , Lasers , Solanum lycopersicum/classification , Male , Mice , Mice, Inbred C57BL , Plant Extracts/pharmacology , Platelet Aggregation/drug effects , Platelet Function Tests/methods , Rats , Rats, Wistar , Species Specificity , Thrombosis/etiology
9.
Thromb Res ; 105(6): 507-11, 2002 Mar 15.
Article in English | MEDLINE | ID: mdl-12091051

ABSTRACT

Platelet reactivity in stroke-prone spontaneously hypertensive rats (SHRSP) and normotensive Wistar-Kyoto rats (WKY) were compared. In vivo platelet reactivity was tested by the He-Ne laser-induced thrombosis model. The number of laser pulses needed to reach thrombotic occlusion of the targeted vessel was used as an index of thrombogenicity. SHRSP rats needed significantly less number of irradiation to reach occlusion than WKY rats (SHRSP vs. WKY, 5.1+/-0.3 vs. 8.1+/-0.6), indicating enhanced thrombotic response in SHRSP rats. Further, acetylcholine administration significantly increased the number of laser pulses until occlusion in WKY but not in SHRSP rats. This suggests an impaired thrombotic reaction in acetylcholine-treated WKY but not in SHRSP rats. Platelet reactivity in vitro was measured in native blood by a shear-induced haemostasis test (haemostatometry). Indexes of this test (H1/H2), which inversely correlated with platelet reactivity, were significantly greater in SHRSP than in WKY rats (SHRSP vs. WKY, H1: 1815+/-192 vs. 763+/-75; H2: 7547+/-723 vs. 3536+/-264). This suggests reduced platelet reactivity in SHRSP compared with WKY rats. Thus, the present findings show increased thrombotic tendency in SHRSP rats in vivo despite reduced platelet reactivity in vitro. To explain this contradiction, we suggest that an increased in vivo thrombotic tendency may be due to impaired nitric oxide (NO) release from endothelial cells in SHRSP rats, and that a reduced platelet reactivity in vitro may be due to an adaptation of SHRSP rats to survive at extremely high blood pressure.


Subject(s)
Endothelium, Vascular/metabolism , Nitric Oxide/metabolism , Rats, Inbred SHR/physiology , Stroke/etiology , Acetylcholine/administration & dosage , Acetylcholine/pharmacology , Adaptation, Physiological , Animals , Disease Models, Animal , Hypertension/etiology , Lasers , Male , Nitric Oxide/pharmacology , Platelet Activation , Rats , Rats, Inbred WKY , Stress, Mechanical , Thrombosis/etiology
10.
Clin Exp Pharmacol Physiol ; 29(1-2): 73-8, 2002.
Article in English | MEDLINE | ID: mdl-11906462

ABSTRACT

1. The effects of oestrogen on thrombogenesis and the cerebral microcirculation of the female rat were studied during the oestrous cycle and after ovariectomy. 2. Serum levels of oestradiol (E2) and plasma concentrations of nitric oxide (NO) metabolites were significantly greater at pro-oestrus than at dioestrus. Blood vessel diameter, mean red cell velocity, wall shear rate and blood flow at pro-oestrus were significantly higher than at dioestrus. Thrombotic tendency, assessed using a He-Ne laser-induced thrombosis model, was significantly decreased at pro-oestrus compared with dioestrus. 3. The long-term deprivation of oestrogen by ovariectomy significantly depressed serum levels of E2 and plasma concentrations of NO metabolites. Thrombotic tendency was significantly increased 4 weeks after ovariectomy. Vessel diameter, mean red cell velocity, wall shear rate and blood flow in pial arterioles were significantly reduced after ovariectomy. 4. Exogenous administration of oestrogen (17 beta-oestradiol) after surgery reversed the increased thrombotic tendency mediated by ovariectomy. 5. These results strongly indicate that oestrogen mediates beneficial effects on the cerebral microcirculation and moderates cerebral thrombotic mechanisms in the female rat.


Subject(s)
Cerebrovascular Circulation/physiology , Estrous Cycle/physiology , Intracranial Thrombosis/physiopathology , Ovariectomy , Animals , Arterioles/drug effects , Arterioles/physiology , Blood Flow Velocity/drug effects , Blood Flow Velocity/physiology , Cerebral Arteries/drug effects , Cerebral Arteries/physiology , Cerebrovascular Circulation/drug effects , Estradiol/pharmacology , Estradiol/therapeutic use , Estrous Cycle/drug effects , Female , Intracranial Thrombosis/drug therapy , Intracranial Thrombosis/metabolism , Microcirculation/drug effects , Microcirculation/physiology , Ovariectomy/statistics & numerical data , Rats , Rats, Wistar
11.
J Pharm Pharmacol ; 54(2): 263-8, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11848290

ABSTRACT

The aim of this study was to determine the effect of FR183998 (5-(2,5-dichlorothiophen-3-yl)-3-[(2-dimethylaminoethyl)carbamoyl]benzoylguanidine dihydrochloride), an Na+/H+ exchange inhibitor, on myocardial interleukin-8 (IL-8) content and myocardial infarct size in a rat ischaemia and reperfusion model. Rats underwent 30 min of ischaemia followed by 1 to 24 h of reperfusion. IL-8 content rapidly increased in reperfused rat hearts. The maximum increase in IL-8 was obtained after 3 h of reperfusion. Intravenous administration of FR183998 at 1 and 3.2 mg kg(-1), 5 min before ischaemia, significantly reduced the IL-8 level after 3 h of reperfusion (122 +/- 16 and 149 +/- 23 pg mg(-1) protein, respectively), compared with that of the saline-treated group (258 +/- 27 pg mg(-1) protein). Myeloperoxidase activity after 3 h of reperfusion was also reduced by FR183998 (from 0.83+0.19 unit g(-1) weight of tissue in the saline-treated group to 0.36 +/- 0.09 and 0.33 +/- 0.06 unit g(-1) weight of tissue in FR183998-treated groups at 1.0 and 3.2 mg kg(-1), respectively). Myocardial infarction induced by 30 min of ischaemia and 24 h of reperfusion was significantly suppressed by the same doses of FR183998 (14.0 +/- 1.5,13.5 +/- 1.9% at 1.0 and 3.2 mg kg(-1)), compared with 22.2+2.7% in the saline-treated group. These results suggestthat IL-8 may contribute to the generation of myocardial infarction in an ischaemia and reperfusion model in rats.


Subject(s)
Guanidines/therapeutic use , Interleukin-8/biosynthesis , Myocardial Infarction/drug therapy , Myocardial Ischemia/drug therapy , Myocardial Reperfusion Injury/drug therapy , Sodium-Hydrogen Exchangers/antagonists & inhibitors , Thiophenes/therapeutic use , Animals , Depression, Chemical , Disease Models, Animal , Male , Myocardial Infarction/etiology , Myocardial Ischemia/complications , Myocardial Ischemia/metabolism , Myocardial Reperfusion Injury/complications , Myocardial Reperfusion Injury/metabolism , Peroxidase/metabolism , Rats , Rats, Sprague-Dawley
12.
Jpn J Pharmacol ; 87(2): 110-6, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11700009

ABSTRACT

Inhibition of Na+/H+ exchanger has been reported to protect hearts from ischemia and reperfusion injury. However, the effect of Na+/H+ exchange inhibition on hypothermic ischemic injury has not been extensively studied and the results are inconsistent. The purpose of this study was to investigate whether inhibition of Na+/H+ exchange with FR183998 (5-(2,5-dichlorothiphen-3-yl)-3-[(2-dimethylaminoethyl)carbamoyl]benzoylguanidine dihydrochloride), a potent Na+/H+ exchange inhibitor, would show protective effects against postischemic cardiac dysfunction after hypothermic as well as normothermic ischemia and furthermore, after hypothermic cardioplegic arrest in isolated rat hearts. FR183998 (3.2 x 10(-8)-3.2 x 10(-7) M) improved post-ischemic recovery of left ventricular developed pressure and suppressed the increase of left ventricular end diastolic pressure in a dose-dependent manner, after not only 45 min of normothermic ischemia but also 6 h of hypothermic ischemia. Furthermore, FRI 83998 (10(-7)-10(-6) M) significantly reduced creatine kinase release during reperfusion after 3 h of hypothermic ischemia with cardioplegia. These results indicate that FR183998 has a potent protective effect on postischemic cardiac dysfunction after normothermic and hypothermic ischemia, and also on reperfusion injury after hypothermic cardioplegic arrest, suggesting that its effect would be additive to cardioplegia.


Subject(s)
Cardiotonic Agents/pharmacology , Guanidines/pharmacology , Myocardial Ischemia/complications , Myocardial Reperfusion Injury/prevention & control , Sodium-Hydrogen Exchangers/antagonists & inhibitors , Thiophenes/pharmacology , Animals , Blood Flow Velocity/drug effects , Cold Temperature , Creatine Kinase/metabolism , Heart Arrest, Induced/adverse effects , In Vitro Techniques , Male , Myocardial Ischemia/physiopathology , Myocardial Reperfusion Injury/etiology , Myocardial Reperfusion Injury/physiopathology , Rats , Rats, Sprague-Dawley , Rats, Wistar , Ventricular Dysfunction, Left/etiology , Ventricular Function, Left/drug effects , Ventricular Pressure/drug effects
13.
Eur J Pharmacol ; 431(1): 11-6, 2001 Nov 09.
Article in English | MEDLINE | ID: mdl-11716837

ABSTRACT

(E)-N-ethyl-N-(6,6-dimethyl-2-hepten-4-ynyl)-3-[2-methyl-2-(3-thienylmethoxy)propyloxy]benzylamine hydrochloride (FR194738) inhibited squalene epoxidase activity in HepG2 cell homogenates with an IC50 value of 9.8 nM. In the study using intact HepG2 cells, FR194738 inhibited cholesterol synthesis from [14C]acetate with an IC50 value of 4.9 nM, and induced intracellular [14C]squalene accumulation. On the other hand, the 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase inhibitor simvastatin reduced both cholesterol and squalene synthesis from [14C]acetate. Incubation with simvastatin for 18 h produced increases in HMG-CoA reductase activity in HepG2 cells, which was related to the degree of reduction in cholesterol synthesis. The HMG-CoA reductase activity increased by 13- and 19-fold at the concentrations of simvastatin that inhibited cholesterol synthesis by 65% and 82%, respectively. In contrast, FR194738 did not increase HMG-CoA reductase activity at the concentrations that inhibited cholesterol synthesis by 24% and 69%, and moderate increase (4.6-fold) was observed at the concentration that inhibited cholesterol synthesis by 90%. These results suggest that non-sterol metabolite(s) derived from mevalonate prior to the squalene epoxidation step in the cholesterol synthetic cascade have a regulatory role in the suppression of HMG-CoA reductase activity. We speculate that FR194738 inhibits cholesterol synthesis with a minimal change of the regulator(s) and would be highly effective in the treatment of hypercholesterolemia.


Subject(s)
Benzylamines/pharmacology , Cholesterol/metabolism , Enzyme Inhibitors/pharmacology , Oxygenases/antagonists & inhibitors , Simvastatin/analogs & derivatives , Cholesterol/biosynthesis , Humans , Hydroxymethylglutaryl CoA Reductases/isolation & purification , Hydroxymethylglutaryl CoA Reductases/metabolism , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Molecular Structure , Simvastatin/pharmacology , Squalene/metabolism , Squalene Monooxygenase , Tumor Cells, Cultured
14.
Eur J Pharmacol ; 428(2): 295-302, 2001 Oct 05.
Article in English | MEDLINE | ID: mdl-11675048

ABSTRACT

We describe the pharmacological characteristics of a novel phosphodiesterase type 5 inhibitor FR226807, N-(3,4-dimethoxybenzyl)-2-[[(1R)-2-hydroxy-1-methylethyl]amino]-5-nitrobenzamide. FR226807 inhibited phosphodiesterase type 5 isolated from human platelets with an IC(50) value of 1.1 nM. FR226807 also inhibited phosphodiesterase type 6 with an IC(50) of 20 nM; however, the IC(50) value for phosphodiesterase type 6 was 18-fold higher than that for phosphodiesterase type 5. The IC(50) values of FR226807 for other phosphodiesterases (phosphodiesterase type 1, phosphodiesterase type 2, phosphodiesterase type 3, and phosphodiesterase type 4) were 1000-fold higher than that for phosphodiesterase type 5. FR226807 increased the cyclic guanosine monophosphate (cGMP) content in corpus cavernosum isolated from rabbit, an effect associated with relaxation of the muscle. FR226807 enhanced the relaxation response induced by electrical field stimulation of corpus cavernosum isolated from the rabbit. In an anesthetized dog model for the evaluation of erectile function, intravenous administration of FR226807 prolonged the time to return to 75% of maximal intracavernosal pressure after cessation of electrical stimulation of the pelvic nerve. In summary, FR226807 is a potent and highly selective phosphodiesterase type 5 inhibitor with an augmentative effect on penile erection and will be useful for the treatment of erectile dysfunction.


Subject(s)
Benzamides/pharmacology , Phosphodiesterase Inhibitors/pharmacology , Phosphoric Diester Hydrolases/drug effects , 3',5'-Cyclic-GMP Phosphodiesterases , Animals , Blood Pressure/drug effects , Cyclic GMP/metabolism , Cyclic Nucleotide Phosphodiesterases, Type 5 , Dogs , Dose-Response Relationship, Drug , Electric Stimulation , Humans , In Vitro Techniques , Isoenzymes/antagonists & inhibitors , Isoenzymes/metabolism , Male , Muscle Contraction/drug effects , Muscle Relaxation/drug effects , Penis/drug effects , Penis/metabolism , Penis/physiology , Phosphoric Diester Hydrolases/metabolism , Piperazines/pharmacology , Pressure , Purines , Rabbits , Sildenafil Citrate , Sulfones , Time Factors
15.
Br J Pharmacol ; 134(5): 995-1002, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11682447

ABSTRACT

1. The effect of the immunosuppressant drug, cyclosporin A (CsA), on the nitric oxide (NO)-cyclic GMP pathway was examined in spontaneous hypertensive rats (SHR). 2. CsA (50 mg kg(-1)) treatment for 14 days induced typical CsA nephrotoxicity, which was characterized by morphological changes in the glomerulus and proximal tubule as well as an abnormality of creatinine clearance, FENa and BUN. 3. CsA significantly decreased both NOS activity in the kidney and NOx contents in urine, but significantly increased cyclic GMP content in the kidney. 4. A marked change in two kinds of enzyme, which contribute towards the increase in cyclic GMP in tissue, namely, a decrease in cyclic GMP-phosphodiesterase activity and increase in guanylate cyclase activity, was observed in the kidney treated with CsA. 5. In the isolated perfused kidney, a decreased in perfusion pressure induced by SNP in the kidney isolated from CsA group was significantly greater than that of control. 6. There seem to exist a reciprocal mechanism to maintain cyclic GMP content via both a decrease in cyclic GMP degradation and an increase in synthesis of cyclic GMP in the kidney treated with CsA. This mechanism is likely to be playing an important role to regulate the homeostasis in the kidney with CsA nephrotoxicity.


Subject(s)
3',5'-Cyclic-GMP Phosphodiesterases/metabolism , Cyclic GMP/metabolism , Cyclosporine/pharmacology , Guanylate Cyclase/metabolism , Hypertension/metabolism , Kidney Diseases/metabolism , Animals , Body Weight/drug effects , Dose-Response Relationship, Drug , Hypertension/physiopathology , Immunosuppressive Agents/pharmacology , In Vitro Techniques , Kidney/drug effects , Kidney/metabolism , Kidney/pathology , Kidney Diseases/chemically induced , Kidney Diseases/physiopathology , Male , Nitrates/urine , Nitric Oxide/metabolism , Nitric Oxide Synthase/drug effects , Nitric Oxide Synthase/metabolism , Nitrites/urine , Nitroprusside/pharmacology , Perfusion , Pressure , Rats , Rats, Inbred SHR , Vasodilator Agents/pharmacology
16.
J Inorg Biochem ; 85(2-3): 179-86, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11410238

ABSTRACT

Recently, we have shown that a newly synthesized vanadyl complex, bis(1-oxy-2-pyridinethiolato)oxovanadium(IV), VO(opt)(2), is a potent orally active insulin-mimetic in treating streptozotocin-induced diabetes in rats, with long-term action. In the present study, the anti-diabetic effect of VO(opt)(2) and its mechanism in ob/ob mice, an obese non-insulin-dependent diabetes mellitus (NIDDM) animal model, was investigated. In ob/ob mice, 15-day oral treatment with VO(opt)(2) resulted in a dose-dependent decrease in the levels of glucose, insulin and triglyceride in blood. VO(opt)(2) was also effective in ameliorating impaired glucose tolerance in ob/ob mice, when an oral glucose tolerance test was performed after treatment with VO(opt)(2). Tumor necrosis factor-alpha (TNF-alpha) is a key component of obesity-diabetes link, we therefore examined the attenuating effect of VO(opt)(2) on impaired insulin signal transduction induced by TNF-alpha. Elevated expression of TNF-alpha was observed in the epididymal and subcutaneous fat tissues of ob/ob mice. Incubation of 3T3-L1, mouse adipocytes, with TNF-alpha reduced the phosphorylation of insulin receptor substrate-1 (IRS-1), whereas VO(opt)(2) treatment resulted in an enhancement of IRS-1 phosphorylation, irrespective of the presence or absence of TNF-alpha. Overall, the present study demonstrates that VO(opt)(2) exerts an anti-diabetic effect in ob/ob mice by ameliorating impaired glucose tolerance, and furthermore, attenuates the TNF-alpha-induced decrease in IRS-1 phosphorylation in adipocytes. These results suggest that the anti-diabetic action of VO(opt)(2) is derived from an attenuation of a TNF-alpha induced impaired insulin signal transduction via inhibition of protein tyrosine phosphatase, providing a potential clinical utility for VO(opt)(2) in the treatment of NIDDM.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Insulin Resistance , Organometallic Compounds/pharmacology , Vanadates/pharmacology , 3T3 Cells , Adipose Tissue/drug effects , Adipose Tissue/metabolism , Administration, Oral , Animals , Blood Glucose/drug effects , Diabetes Mellitus, Type 2/blood , Insulin/blood , Insulin Receptor Substrate Proteins , Insulin Resistance/genetics , Kinetics , Leptin/genetics , Male , Mice , Mice, Inbred C57BL , Mice, Obese , Organometallic Compounds/administration & dosage , Phosphoproteins/metabolism , Phosphorylation/drug effects , Triglycerides/blood , Tumor Necrosis Factor-alpha/drug effects , Tumor Necrosis Factor-alpha/metabolism , Vanadates/administration & dosage
17.
Life Sci ; 68(12): 1439-48, 2001 Feb 09.
Article in English | MEDLINE | ID: mdl-11388695

ABSTRACT

The effects of zenarestat, 3-(4-bromo-2-fluorobenzyl)-7-chloro-3,4-dihydro-2,4-dioxo-1(2H)-quinazolineacetic acid, an aldose reductase inhibitor (ARI), on F-wave conduction abnormalities, nerve blood flow (NBF) reduction and sorbitol accumulation were studied in streptozotocin-induced diabetic rats. Two weeks after the induction of diabetes, zenarestat was given once a day for two weeks. In diabetic control rats, marked accumulation of sorbitol, reduction of NBF and prolongation of minimal F-wave latency (FWL) were observed as compared to normal rats. Zenarestat, at a dose of 32 mg/kg, inhibited sorbitol concentration to nearly the normal rat level and significantly improved not only NBF but also minimal FWL. At a dose of 3.2 mg/kg, sorbitol accumulation was inhibited by approximately 40% and there was a tendency to increase in NBF; however, minimal FWL was not improved at all. These data suggest that a highly inhibition of the nerve sorbitol accumulation is requisite for the treatment of diabetic peripheral neuropathy.


Subject(s)
Aldehyde Reductase/antagonists & inhibitors , Diabetes Mellitus, Experimental/metabolism , Enzyme Inhibitors/pharmacology , Neural Conduction/drug effects , Quinazolines/pharmacology , Reaction Time/drug effects , Sciatic Nerve/blood supply , Animals , Blood Flow Velocity/drug effects , Diabetes Mellitus, Experimental/drug therapy , Diabetic Neuropathies/drug therapy , Enzyme Inhibitors/therapeutic use , Male , Neural Conduction/physiology , Quinazolines/therapeutic use , Rats , Rats, Sprague-Dawley , Streptozocin
18.
Eur J Pharmacol ; 419(1): 99-105, 2001 May 04.
Article in English | MEDLINE | ID: mdl-11348636

ABSTRACT

FK506 (Tacrolimus) is an effective immunosuppressant currently used worldwide in organ transplantation. Based on our recent findings that insulin-like growth factor-I (IGF-I) is important for the stimulation of choleresis in vivo, in this study we investigated the effect of FK506 on bile flow and the plasma and hepatic levels of IGF-I in rats. Intravenous treatment of rats with FK506 resulted in a significant increase in bile flow, whereas cyclosporin A induced a significant decrease. A significant increase in plasma levels of IGF-I was observed in rats 30 min after a single intravenous administration of FK506. Oral treatment of rats with FK506 for 1 week also resulted in an increase in both plasma and hepatic levels of IGF-I. Overall, this study showed that FK506 treatment increased bile flow and also induced an increase in the plasma and hepatic levels of IGF-I in rats, suggesting that a stimulation of hepatic IGF-I production by FK506 may contribute to its choleretic profile.


Subject(s)
Bile/metabolism , Immunosuppressive Agents/pharmacology , Insulin-Like Growth Factor I/metabolism , Liver/drug effects , Tacrolimus/pharmacology , Animals , Cyclosporine/pharmacology , Hypophysectomy , Immunosuppressive Agents/administration & dosage , Insulin-Like Growth Factor I/chemistry , Liver/chemistry , Liver/metabolism , Male , Rats , Rats, Sprague-Dawley , Tacrolimus/administration & dosage
19.
Hypertens Res ; 24(6): 735-42, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11768736

ABSTRACT

The preventive effects of sesamin, a lignan from sesame oil, and vitamin E on hypertension and thrombosis were examined using stroke-prone spontaneously hypertensive rats (SHRSP). At 5 weeks of age the animals were separated into four groups: (i) a control group; (ii) a vitamin E group, which was given a 1,000 mg alpha-tocopherol/kg diet; (iii) a sesamin group, given a 1,000 mg sesamin/kg diet; and (iv) a vitamin E plus sesamin group, given a 1,000 mg alpha-tocopherol plus 1,000 mg sesamin/kg diet for 5 weeks from 5 to 10 weeks of age. Resting blood pressure was measured by the tail-cuff method once weekly. A closed cranial window was created and platelet-rich thrombi were induced in vivo using a helium-neon laser technique. The number of laser pulses required for formation of an occlusive thrombus was used as an index of thrombotic tendency. In control rats, systolic blood pressure and the amount of urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) became significantly elevated with age. However, the elevation in blood pressure and 8-OHdG were significantly suppressed in rats administrated vitamin E, sesamin, or vitamin E plus sesamin. At 10 weeks, the number of laser pulses required to induce an occlusive thrombus in arterioles of the control group was significantly lower than in the other groups (p<0.05). These results indicate that chronic ingestion of vitamin E and sesamin attenuated each of elevation in blood pressure, oxidative stress and thrombotic tendency, suggesting that these treatments might be beneficial in the prevention of hypertension and stroke.


Subject(s)
Cerebrovascular Disorders/etiology , Deoxyguanosine/analogs & derivatives , Dioxoles/pharmacology , Hypertension/physiopathology , Lignans/pharmacology , Thrombosis/etiology , Vitamin E/pharmacology , 8-Hydroxy-2'-Deoxyguanosine , Animals , Blood Pressure/drug effects , Blood Vessels/drug effects , Body Weight , Cerebrovascular Circulation/drug effects , Deoxyguanosine/urine , Disease Susceptibility , Drug Combinations , Genetic Predisposition to Disease , Hypertension/pathology , Male , Microcirculation/drug effects , Rats , Rats, Inbred SHR/genetics , Stroke/genetics , Vasomotor System/drug effects
20.
Metabolism ; 49(11): 1395-9, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11092500

ABSTRACT

We studied the effects of zenarestat, an aldose reductase inhibitor (ARI), on peripheral neuropathy in Zucker diabetic fatty (ZDF) rats, an animal model of type 2 diabetes. ZDF rats and their lean rats counterparts were fed a sucrose-containing diet, and zenarestat was given orally once a day for 8 weeks. Motor nerve conduction velocity (MNCV), F-wave minimal latency (FML), and sorbitol concentrations in the sciatic nerve were measured. In ZDF control rats, a remarkable accumulation of sorbitol, a delay in FML, and a slowing of MNCV were observed compared with lean rats. At a dose of 3.2 mg/kg, zenarestat had no significant effect on the delay in FML and the slowing of MNCV, although the sorbitol accumulation in the sciatic nerve was partially inhibited in ZDF rats. On the other hand, 32 mg/kg zenarestat treatment improved these nerve dysfunctions in ZDF rats, along with a reduction of nerve sorbitol accumulation almost to the level of lean rats. These data showed that zenarestat improved diabetic peripheral neuropathy in ZDF rats, a type 2 diabetes model, providing evidence for the therapeutic potential of zenarestat for the treatment of diabetic neuropathy.


Subject(s)
Aldehyde Reductase/antagonists & inhibitors , Diabetic Neuropathies/drug therapy , Enzyme Inhibitors/therapeutic use , Quinazolines/therapeutic use , Animals , Blood Glucose/analysis , Body Weight , Diabetes Mellitus, Type 2/complications , Diabetic Neuropathies/complications , Diabetic Neuropathies/physiopathology , Disease Models, Animal , Enzyme Inhibitors/pharmacology , Male , Quinazolines/pharmacology , Rats , Rats, Zucker
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