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141.
142.
We have shown that Protease N treated Royal Jelly (ProRJ) and peptides from ProRJ (Ile-Tyr (IY), Val-Tyr (VY), Ile-Val-Tyr (IVY)) inhibited angiotensin I-converting enzyme (ACE) activity and they have an antihypertensive effect in repeated oral administration for 28 d on spontaneously hypertensive rats (SHR). We investigated the contributive ratio of these peptides in ProRJ for antihypertensive effect in single oral administration on SHR. In single oral administration of each peptide and peptides mixture (MIX; IY, VY and IVY) at doses of 0.5, 1 and 10 mg/kg, systolic blood pressure (SBP) of SHR was reduced dose-dependently. This antihypertensive effect was held for 8 h. These results suggest that peptides contributed to the antihypertensive effect of ProRJ. And the contributive ratio of MIX in ProRJ for antihypertensive effect was computed to be about 38%. Therefore it is considered that intake of peptides, as a functional food would be beneficial for improving blood pressure in people with hypertension.  相似文献   
143.
To clarify the mechanisms underlying the antihypertensive effect of Luobuma (Apocynum venetum L. (Apocynaceae)) leaf extract (LLE), we investigated the vasodilator effect of LLE in the rat mesenteric vascular bed, which plays an important role in changes in peripheral resistance and thus the regulation of blood pressure. In the perfused mesenteric vascular bed with active tone and intact endothelium, perfusion of LLE (0.1 ng to 100 mg/ml for 15 min) caused dose-dependent vasodilation, which was abolished by chemical removal of the endothelial layer with perfusion of sodium deoxycholate, but not by N(G)-nitro-L-arginine-methyl ester (L-NAME), a competitive inhibitor of nitric oxide (NO), which instead increased the effect. The LLE-induced vasodilation was partially inhibited by high K(+)-containing Krebs solution and tetraethylammonium (a K(+) channel blocker) and completely by the combination of L-NAME and high K(+)-Krebs solution. However, atropine (a muscarinic acetylcholine receptor antagonist) did not affect the vasodilation. These results suggest that the vasodilation induced by LLE is endothelium-dependent and mediated by endothelium-derived hyperpolarizing factor, which involves the activation of K(+)-channels. The higher concentrations of LLE may enhance NO production/release to cause vasodilation.  相似文献   
144.
PURPOSE: Intratumoral (i.t.) vaccination represents a potential modality for the therapy of tumors. Previous i.t. vaccination studies have focused on the efficacy of i.t. vaccination alone. There are no reports that clearly compared i.t. vaccination with systemic vaccination achieved by s.c., intradermal, or i.m. injection, or combining both modalities of systemic and i.t. vaccination. Here, we compared the antitumor effects induced by a systemic vaccination regimen (s.c.) and i.t. vaccination, and a sequential s.c/i.t. vaccination regimen. In this study, we used a recombinant vaccinia virus containing the transgenes for carcinoembryonic antigen (CEA) and a triad of T-cell costimulatory molecules (B7-1, ICAM-1, and LFA-3; designated rV-CEA/TRICOM) for s.c. priming and a replication defective avipox (fowlpox) virus containing the same four transgenes (designated rF-CEA/TRICOM) for i.t. vaccination or s.c. booster vaccinations. EXPERIMENTAL DESIGN: Vaccination was started on day 8 after s.c. implantation with CEA-positive tumors. We compared the antitumor activity induced by these vaccines when administered via the i.t. route versus the s.c. route. Subsequent therapy studies examined the sequential combination of these routes, s.c. priming with rV-CEA/TRICOM followed by i.t. boosting with rF-CEA/TRICOM. Initial studies were conducted in conventional mice to define optimal vaccine regimens and then in CEA-transgenic mice that expressed CEA as a "self" antigen in a manner similar to that of an advanced colorectal cancer patient. RESULTS: The results demonstrate that the antitumor activity induced by i.t. vaccination is superior to that induced by s.c. vaccination. For more advanced tumors, a s.c. priming vaccination, followed by i.t. boosting vaccinations was superior to either s.c. or i.t. vaccination alone. Both of these phenomena were observed in tumor models where the tumor-associated antigen is a foreign antigen and in a CEA-transgenic tumor model where the tumor-associated antigen is a self-antigen. The cytokine, granulocyte macrophage colony-stimulating factor admixed in vaccines, was shown to be essential in inducing the antitumor activity. CONCLUSIONS: These studies demonstrate that the diversified vaccine regimens that consisted of s.c. prime and i.t. boosts with CEA/TRICOM vectors could induce antitumor therapy superior to that seen by either route alone.  相似文献   
145.
The prevalence of virulent Rhodococcus equi in soil collected from 17 domestic animal farms (from 12 cattle, 1 pig, and 4 horse farms) and in 6 clinical specimens from patients with acquired immune deficiency syndrome (AIDS) in Chiang Mai, Thailand, was investigated. The isolates were tested for the presence of 15-17-kDa antigens (VapA) and a 20-kDa antigen (VapB) by immunoblotting and for the presence of virulence plasmid DNA. Rhodococcus equi was isolated from most soil samples (68 of 80) obtained from the 17 farms, with 2.0 x 10(2) to 6.0 x 10(5) colony-forming units per gram of soil. We detected VapA in none of the 537 isolates from the soil samples. In one isolate from a pig farm, both VapB and virulence plasmid DNA were detected. Of the 6 clinical isolates from patients with AIDS, however, 4 isolates contained both VapB and virulence plasmid DNA. The remaining 2 isolates were avirulent.  相似文献   
146.
Incorporating the wavelength dependence of the scattering effect into a simple linear multicomponent analysis of intrinsic optical signals, we have reexamined the change in the hemoglobin (Hb) concentration and the origins of intrinsic signals in somatosensory cortex evoked with electrical stimulation of the hind limb (5 Hz, 2 s) of anesthetized rat. The concept of the analysis was to separate the effect of light scattering involved in the observed optical signals into two factors, light attenuation and modification of Hb absorption as a result of the wavelength dependence of the optical path length. This dependency was experimentally assessed with a tissue-simulating phantom whose absorption spectra were nearly identical to those of cerebral tissue through a thinned skull window in vivo. Using those phantom spectra, we carried out a curve fitting of the reflection spectra from the rat somatosensory cortex activated with an electrical stimulation of hind limb (5 Hz, 2 s). Oxygenated Hb slightly decreased at 0.5-1.5 s after an onset of the stimulus followed by an increase, which peaked at 4 s. Deoxygenated Hb increased at 1.0-1.5 s followed by a large late decrease. We again confirmed an early increase in the concentration of deoxygenated Hb in the rat somatosensory cortex after stimulation of the hind limb.  相似文献   
147.
BACKGROUND: To understand what happens during the wound healing process of the mesothelium, we have developed an in vitro wounding model of cultured human peritoneal mesothelial cells (HPMCs) utilizing an image acquisition and analysis system. Using this system, cell mobility and hyaluronan synthesis were quantified and their interrelationship discussed. METHODS: 1N NaOH was used to create circular wounds in cultured HPMC monolayers, which were then exposed for 30 minutes to the peritoneal dialysis solutions or fetal calf serum (FCS)-free M199 culture medium, followed by incubation with 0.3% FCS/M199 culture medium for up to 96 hours. Digitalized microscopic date was captured every 30 minutes to quantify the wound healing process. In separate experiments, the HPMC monolayers were stained with biotin-conjugated hyaluronan-binding protein (B-HABP) at a regular time interval. RESULTS: Centripetal migration of the HPMCs into the wound area was the predominant process involved in wound repair with proliferation playing a secondary role. Two noticeable observations were made from the digital video movies: (1) cell mobility varied and was dependent upon the morphology and location of the cell relative to the wound edge, and (2) cell migration continued even after wound closure. Staining for B-HABP was confined to the remesothelialized area when wound closure was complete at 24 hours. At 48 hours after wound closure, the stained area was even more visible, although somewhat diffuse; thereafter, staining was reduced to almost background levels. CONCLUSION: The cell culture model of wound healing used in our study has enabled us to demonstrate quantitative image data of the cellular processes that occur during wound healing. We have been able to continuously observe cell migration, proliferation, and transformation. Synthesis and subsequent decomposition of hyaluronan appears to be related to the mobility of the wounded and intact HPMCs in this model system.  相似文献   
148.
BACKGROUND: Combination chemotherapy using an oral combination of uracil and tegafur (UFT) plus cisplatin and concurrent thoracic radiotherapy is reported to have a high response rate and less toxicity for locally advanced non-small-cell lung cancer (NSCLC) patients. We performed a phase II trial using this chemoradiotherapy as an induction treatment. METHODS: Patients with marginally resectable stage IIIB NSCLC, an age younger than 70 years, a performance status of 0 or 1, and good organ function were eligible. The UFT (400 mg/m(2)) was administered orally on days 1 through 14 and 22 through 35 and cisplatin (80 mg/m(2)) was injected intravenously on days 8 and 29. Radiotherapy with a total dose of 40 Gy was delivered in 20 fractions from day 1. A surgical resection was performed from 3 to 6 weeks after completing the induction treatment. RESULTS: Twenty-seven patients, 18 male and 9 female with a median age of 56 years and ranging from 36 to 69 years, were entered into the phase II trial. Clinical T4 and N3 cancers were observed in 22 and 7 patients, respectively. Twenty-five (93%) achieved a partial response. The most frequently observed adverse event was grade 3 leukopenia in 26%. Of 25 patients who underwent a thoracotomy, 22 had a tumor resection. In all 22 patients a complex resection including a resection of the superior vena cava, carina, and vertebrae was required. Operative morbidity and mortality rates were 36% and 4% respectively. The calculated 1-year and 3-year survival rates of all 27 patients were 73% and 56% respectively. CONCLUSIONS: Chemotherapy using UFT plus cisplatin and concurrent radiotherapy as induction treatment and a surgical resection for patients with marginally resectable stage IIIB NSCLC is feasible and promising. However it is difficult to conduct multi-institutional trials even for selected stage IIIB disease as a complex resection in almost all patients is necessary.  相似文献   
149.
In the present study, we evaluated the relationship between the antihypertensive effect of sesamin, a lignan from sesame oil, and its antioxidative activity in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. After a 5-week treatment period, systolic blood pressure was significantly elevated in normal diet-fed DOCA-salt animals compared with cases in sham-operated animals. Sesamin feeding, tempol (a superoxide dismutase mimetic) treatment or antihypertensive drugs combination (triple therapy; reserpine, hydralazine, hydrochlorothiazide) significantly suppressed the development of DOCA-salt-induced hypertension. Compared with sham-operated rats, the normal diet-fed DOCA-salt rats revealed marked increases in aortic superoxide (O(2)(-)) production. These increases in O(2)(-) production were significantly suppressed by sesamin feeding or tempol treatment, but not by triple therapy. Acetylcholine (Ach)-induced endothelium-dependent relaxation was markedly decreased in normal diet-fed DOCA-salt rats, compared with cases in sham-operated rats. Sesamin feeding and triple therapy significantly improved the DOCA-salt-induced impairment of endothelium-dependent relaxation. However, tempol treatment had no effect on the impaired vasodilator responses induced by DOCA-salt treatment. In DOCA-salt rats with or without sesamin feeding, systolic blood pressure significantly correlated with both aortic O(2)(-) production and endothelium-dependent vascular relaxation. These findings suggest that sesamin feeding inhibits the enhancement of aortic O(2)(-) production in DOCA-salt hypertensive rats, and this effect may contribute to the antihypertensive effect of sesamin. Sesamin feeding-induced improvement of endothelial dysfunction seems to result from the above antioxidative and antihypertensive effects.  相似文献   
150.
PURPOSE: We report 6 cases of herpes simplex keratitis after ophthalmic surgery, in eyes without clinical history of herpes simplex keratitis. CASES: These cases comprised 6 patients examined at our hospital between April 1992 and November 2001. Past operations were keratoplasty in 5 eyes and cataract surgery in 1 eye. Clinical findings and predisposing factors were evaluated retrospectively. The period between herpetic epithelial keratitis onset and ophthalmic surgery ranged from 1.5 to 79 months. Predisposing factors included corticosteroid therapy and operative wound. The herpetic epithelial lesions were dendritic ulcers in 2 eyes, geographic ulcer in 1 eye, and atypical epithelial lesions in 3 eyes; in all cases, herpes simplex virus (HSV)-DNA was detected by polymerase chain reaction (PCR) in tear fluid. All herpetic epithelial lesions healed with oral and topical acyclovir. CONCLUSIONS: When corticosteroids are used following ophthalmic surgery, physicians should be alert to the possibility of herpetic epithelial keratitis, even in patients with no clinical history of herpes simplex keratitis. PCR detection in tear fluid is helpful in diagnosing this disease.  相似文献   
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