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Kazunori Aizawa Takeshi Hanaoka Hiroki Kasai Kaoru Kogashi Setsuo Kumazaki Jun Koyama Hiroshi Tsutsui Yoshikazu Yazaki Noboru Watanabe Osamu Kinoshita Uichi Ikeda 《Hypertension research》2006,29(2):123-128
The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH. 相似文献
3.
A prognosis of patients with a curative resected advanced cancer of the lower gastric region was worse than that of the other region of the stomach. The 5 year survival rate was only 47.3%. One of the main reasons was that a rate of lymph node recurrence was higher. In this point of view, we studied on lymphatic flow of the lower gastric region using an activated carbon particle (CH40). Lymph nodes were stained black soon after the injection of CH40 into the lower gastric wall at laparotomy. The black stained rate of an each regional lymph node was as follows. 3. 58%, 4. 17%, 5. 50%, 6. 25%, 1. 21%, 7. 58%, 8. 83%, 9. 58%, 11. 17% and 12. 33% in case of injection into the greater curvature and and 4. 31%, 6. 100%, 8. 25%, 9. 25%, 14V and 56% in case of injection into the lesser curvature. The stained rate was relatively high in 12 and 14V lymph node which we had not routinely dissected. The rates of lymph nodes stained black were related to those of cancer metastasis. The results suggest that lymphadenectomy of 12 for the cancer at the lesser curvature and that of 14V for the cancer at the greater curvature might make a prognosis of lower gastric cancer better. 相似文献
4.
A clinical phase I study for T-2588 was carried out in 25 healthy male volunteers. Each volunteer received T-2588 in one of the following doses: 100 mg capsule or tablet as a single oral administration in fasting or non-fasting state, 200 or 400 mg capsule as a single oral administration in non-fasting state or 300 or 600 mg daily for 14 approximately 15 days as a repeated administration in non-fasting state. The results are summarized below. No subjective or objective adverse effects were noted after a single oral administration. But repeated dose of 300 mg daily for 15 days and 600 mg daily for 14 days brought about abdominal distension in 1 case and soft stool in 1 case, respectively. As an abnormal change in clinical laboratory findings, 1 case with slight increase in transaminase after a single administration and 3 cases with slight increases in transaminase after repeated doses were observed. Time to reach a maximum concentration of T-2525 in blood (Tmax) was longer in subjects at non-fasting states than subjects in fasting states. Maximum blood concentration was lower in the latter than in the former. Urinary excretion rate in 8 hours after an oral administration was 19 approximately 28% and it was higher in non-fasting subject than in fasting subject. No accumulation of T-2588 was noted after repeated doses. 相似文献
5.
Alf Lamprecht Hiromitsu Yamamoto Hirofumi Takeuchi Yoshiaki Kawashima 《European journal of pharmaceutics and biopharmaceutics》2005,59(2):367-371
5-Fluorouracil (5-FU) in combination with leucovorin (LV) is nowadays the standard treatment in colon cancer and would be a candidate to be delivered orally to the colon. Eudragit P-4135F or Eudragit RS100 were used separately to prepare microspheres by an oil/oil emulsification process trapping 5-FU and LV simultaneously. Scanning electron microscopy permitted a structural analysis, process parameters were analyzed and drug loading and release profiles were recorded. Particle size varied between 123 (RS100) and 146 microm (P-4135F). Generally, higher encapsulation rates were found with RS100 (5-FU, 60.3+/-9.7%; LV, 81.4+/-8.6%) compared to P-4135F (5-FU, 48.3+/-2.0%; LV, 55.4+/-2.7%). Microparticles made from Eudragit RS100 released the incorporated drug combination within 8 h not exhibiting general differences between the kinetics of both drugs. P-4135F was found to maintain the undesired 5-FU release at pH 6.8 lower than 25% within 4 h while at pH 7.4, a nearly immediate release (within 15 min) was observed. Although the release was similar at pH 7.4, at pH 6.8 LV showed a distinct initial drug loss of about 60% and a complete release within 2 h. SEM analyses revealed a substantial presence of LV crystals on the particle surface provoking a distinct burst effect of LV. These observations were concluded to be related to the high lipophilicity of P-4135F provoking a separation between P-4135F and LV during the preparation process. 相似文献
6.
A monoclonal antibody (MoAb, SK-930) of the IgG2a subclass to human pancreatic carcinoma cells (MIA-PaCa 2) was obtained by hybridization of spleen cells from immunized Balb/c mice with murine myeloma cells. SK-930 was investigated for reacting in indirect immunofluorescence on FACS against a panel comprising 12 types of different origin. SK-930 reacted with seven out of 11 tumor cells and with one PBL. Immunoperoxidase techniques (ABC method) showed that SK-930 antigen was present on pancreatic adenocarcinoma cells, but could not be detected on normal pancreatic tissue. Immunoprecipitation experiments and SDS-PAGE analysis revealed that SK-930 recognized 134K dalton peptide on tumor cells. These results suggest that SK-930 reacts with a novel pancreatic cancer-associated antigen. 相似文献
7.
Hirofumi Tomiyama Jiko Yamada Yutaka Koji Minoru Yambe Kohki Motobe Kazuki Shiina Yoshio Yamamoto Akira Yamashina 《Hypertension research》2007,30(5):417-426
This observational study of Japanese men without metabolic syndrome (MetS) (age: 41+/-8 years) was conducted to clarify whether or not heart rate elevation precedes the development of full-blown MetS. MetS was defined based on two modifications of the criteria of the Japanese Expert Committee on the Diagnosis and Classification of Metabolic Syndrome. Premetabolic syndrome subjects were defined as those having one component of MetS with increased body mass index (BMI). Among the subjects without MetS (n=1,859 when the BMI criterion was >or=25 and n=2,020 when the BMI criterion was >or=27.5), the incidence of progression to full-blown MetS by the time of the second examination at the end of the 3-year study period was higher in the subjects with premetabolic syndrome than in those without it. The receiver-operator characteristic curve analysis and binary logistic regression analysis revealed that the odds ratio (OR) of a heart rate >or=69 beats/min at the first examination for progression to full-blown MetS by the time of the second examination was significant in subjects with premetabolic syndrome (BMI>or=25: OR=3.64 [1.22-10.88]; BMI>or=27.5: OR=3.67 [1.28-10.55]; p<0.05). Thus, heart rate elevation appears to precede the development of full-blown MetS in subjects with premetabolic syndrome. Heart rate seems to be a simple and useful marker for predicting the progression to full-blown MetS of middle-aged Japanese men with premetabolic syndrome. 相似文献
8.
Hirofumi Nakanishi Akira Myoui Takahiro Ochi Katsuyuki Aozasa 《Journal of cancer research and clinical oncology》1997,123(6):352-356
Multidrug resistance (MDR) is an important problem in chemotheraphy for neoplastic disease. In humans, MDR is mainly mediated by P-glycoprotein (P-gp), a product of theMDR1 gene, which acts as a transmembrane protein pump and eliminates chemotherapeutic agents from the cells. Expression of P-gp was immunohistochemically studied by using two monoclonal antibodies, JSB-1 and C-219, on paraffin-embedded sections from 55 patients with soft-tissue sarcoma. The histological diagnosis of tumors was malignant fibrous histiocytoma in 24 cases, liposarcoma in 9, synovial sarcoma in 7, malignant neurogenic tumors in 6, leiomyosarcoma in 5, others in 4. The histological grade was determined on the basis of criteria previously proposed by us. Out of 55 cases, 34 (62%) were positive for P-gp expression. There was a significant difference in P-gp expression between high-grade (90%) and intermediate and low-grade tumors (46%) (P<0.005). Tumors expressing P-gp had a less favorable prognosis than P-gp-negative tumors in the high- and intermediate-grade tumors. The current study demonstrated that the estimation of P-gp expression could be used to select appropriate therapeutic modalities.Abbreviations
MDR
multidrug resistance
-
P-gp
P-glyco-protein 相似文献
9.
Summary cDNA clones spanning the entire region of the peplomer (S) gene of feline infectious peritonitis virus (FIPV) type I strain KU-2 were obtained and their complete nucleotide sequences were determined. A long open reading frame (ORF) encoding 1464 amino acid residues was found in the gene, which was 12 residues longer than the ORF of the FIPV type II strain 79–1146. The sequences of FIPV type I and mainly FIPV type II were compared. The homologies at the N- (amino acid residues 1–693) and C- (residues 694–1464) terminal halves were 29.8 and 60.7%, respectively. This was much lower than that between FIPV type II and other antigenically related coronaviruses, such as transmissible gastroenteritis virus of swine and canine coronavirus. This supported the serological relatedness of the viruses and confirmed that the peplomer protein of FIPV type I has distinct structural features that differ from those of antigenically related viruses. 相似文献
10.