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91.
Recently, the number of human immunodeficiency virus (HIV) -positive patients has increased in Japan. HIV-positive patients are at a higher risk of cancer than the general population. This paper retrospectively reports the acute adverse effects of radiation therapy on HIV-positive patients who were treated at Tokyo Metropolitan Cancer and Infectious diseases Center Komagome Hospital (TMCICK). Thirty-one cases involving 24 HIV-positive cancer patients who were treated at TMCICK from January 1997 to March 2009 were included in this study. All acute adverse effects of radiation therapy were examined during, and one month after, the last radiation therapy session. Acute adverse effects were classified according to the site of radiation therapy treatment and analyzed using the Common Terminology Criteria for Adverse Events (CTCAE) version 3.0. Grade 3 acute adverse effects were seen in 17% of cases, and Grade 2 toxicities were found in 23% of patients. Damage to the skin and mucosa, including stomatitis or diarrhea, tended to occur after low-dose radiation therapy; however, no severe acute adverse effects were seen in other organs, such as the brain, lung, and bone. Acute adverse effects tended to occur earlier in HIV-positive patients and became severe more frequently than in the general population. In particular, disorders of the mucosa, such as those of the oral cavity, pharynx, and intestine, tended to occur rapidly. It was shown that radiation therapy is safe when treatment is performed carefully and that it is a very useful treatment for cancer in HIV-positive patients.  相似文献   
92.
We examined the effects of gamma-aminobutyric acid (GABA) on the blood pressure in spontaneously hypertensive rats and normotensive Wistar-Kyoto rats. A single oral administration (0.5 mg/kg) significantly lowered the systolic blood pressure in spontaneously hypertensive rats, but not in normotensive rats. In the mesenteric arterial bed, the perivascular nerve stimulation-induced increase in perfusion pressure and noradrenaline release were significantly inhibited by GABA in spontaneously hypertensive rats, but not in normotensive rats, and attenuated by the selective GABA(B) receptor agonist, baclofen, but not by the selective GABA(A) receptor agonist muscimol. The inhibitory effects of GABA on the perivascular nerve stimulation-induced increase in perfusion pressure and noradrenaline release were completely antagonized by the selective GABA(B) receptor antagonist, saclofen, but not by the selective GABA(A) receptor antagonist, bicuculline. These results suggest that, in spontaneously hypertensive rats, GABA has an antihypertensive effect due to its inhibition of noradrenaline release from sympathetic nerves in the mesenteric arterial bed via presynaptic GABA(B) receptors.  相似文献   
93.
To enhance the efficacy of an inactivated vaccine against pseudorabies virus (PRV), we evaluated the adjuvant properties of Fc domain of IgG. A cell line expressing mouse IgG Fc chimera on its surface was established. We found that when PRV was propagated in the cells expressing the Fc chimera, PRV virion incorporated the Fc. Immunization of BALB/c mice with inactivated PRV harboring Fc, which had been propagated in the cells expressing Fc on its surface, induced higher antibody production against PRV and protected mice more effectively from lethal challenge of virulent strain, comparing to the immunization with normal inactivated virus. Virus harboring Fc has a great potential as a new inactivated vaccine.  相似文献   
94.
Abstract

Purpose: To evaluate the effects of topical hyaluronan (HA) on corneal epithelial wound healing when administered with or without benzalkonium chloride (BAC).

Methods: A cultured human corneal epithelial cell line (HCE-T) was subjected to in vitro scratch assays and in situ epithelial migration was evaluated in organ-cultured rabbit corneas. The corneal epithelium of C57BL/6J mice was also evaluated to determine in vivo wound healing. An in vivo imaging system was also used to evaluate the effects of HA on eye drop retention on the ocular surface.

Results: The findings revealed the promotion of HCE-T migration, in situ rabbit corneal epithelial migration, and in vivo wound healing in mouse corneal epithelium by HA. Pre-treatment with HA also protected against delayed epithelial wound healing in BAC in vitro. However, pre-treatment with 3?mg/mL HA did not show a protective effect against BAC in vivo, but instead delayed epithelial wound healing and increased detection of cleaved caspase-3. This suggested that HA promotes the retention of BAC on the ocular surface. The instilled HA was retained after 15?min, at a significantly higher rate than for phosphate-buffered saline.

Conclusions: The combination of HA and BAC impaired wound healing in the corneal epithelium.  相似文献   
95.
BACKGROUND: Recently, we found that a 30-mer peptide derived from apoprotein E (apoE) 133-162 has antibiotic activity that is comparable with the classic antibiotics and neutrophil-derived antibiotic peptide. In this study, we tested if apoE 133-162 also has anti-tumor activity against several cancer cell lines. MATERIALS AND METHODS: Two gastric cancer cell lines (MKN-7, MNN-1), two pancreatic cancer cell lines (PANC-1, Paca-2) and one colon cancer cell line (COLO201) were used for MTT cytotoxic assay. Calcein leakage from artificial liposomes was also tested, varying the composition of liposome. RESULTS: The apoE 133-162 peptide had cytotoxic activity against all tested human cancer cell lines in a dose-dependent manner. In the Paca-2 cell, an equivalent cytotoxic activity to 5-FU (10 microg/ml) was observed at about 40 microg/ml of apoE 133-162 peptide, but no synergistic effect of apoE 133-162 (40 microg/ml ) with 5-FU (10 microg/ml), nor inhibitory effect by heparin(100 microg/ml), was observed. In the calcein leakage test, in the presence of 150 mM NaCl, the presence of cholesterol attenuated the membrane perturbation activity of apoE 133-162, and the more acidic membrane was susceptible to lysis. CONCLUSION: ApoE 133-162 has anti-tumor activity, probably through perturbation and formation of ion-permeable "pores" in membranes.  相似文献   
96.
The potency of ambient air for DNA-adduct formation was estimated using Wistar rats. The animals were maintained in a small-animal facility located beside a main highway intersection in Kawasaki City, Japan, for up to 60 weeks and were exposed to roadside air contaminated mainly with automobile emission (exposure group, EG) or to clean air (control group, CG). Compared to CG, the relative adduct levels (RAL) were increased significantly in EG lungs (17.1-fold (P<0.05)), nasal mucosa, and livers after exposure for 4 weeks. However, there were no significant differences in RAL between EG and CG after exposure for 12 weeks, but they were elevated again in EG after exposure for 48 or 60 weeks. These results suggest that roadside air in this region can cause the generation of DNA adducts. This activity of ambient roadside air can be estimated using experimental animals, indicating that biological monitoring of DNA-adduct formation may be a powerful tool to assess the effect of ambient air on human health.  相似文献   
97.
从人参叶中得到的两个微量皂甙成分   总被引:3,自引:0,他引:3       下载免费PDF全文
从有参叶中分离得到两种微量皂甙成分,分别为3β,12β,20(S)-三羟基达玛-24(25)-烯-(20-O-α-L-呋喃阿拉伯糖基(1→6)-β-D-吡喃葡萄糖基)-3-O-β-D-吡喃葡萄糖甙(1),和3β,12β,20(S)-三羟基达玛-24(25)-烯-(20-O-α-L-吡喃阿拉伯糖基(1→6)-β-D-吡喃葡萄糖基-3-O-β-D吡喃葡萄糖甙(2),前者为三七参甙-Fe(notoginsenoside-Fe),后者为一新的天然产物,命名为人参皂甙-Rd2(ginsenoside-Rd2)。  相似文献   
98.
99.
Since HeLa cells possess very little functional p53 activity, they could be originally resistant to genotoxic stress-induced apoptosis. Therefore, it is likely that the drug-resistant cells derived from HeLa cells are more resistant to apoptosis. The aim of this study was to determine whether cisplatin-resistant cells derived from HeLa cells have an apoptosis-resistant phenotype. A cisplatin-resistant cell subline, HeLa/CDDP cells, showed a 19-fold resistance to cisplatin compared with the parent cells. The subline showed a collateral sensitivity to paclitaxel. An equitoxic dose (IC50) of cisplatin produced DNA fragmentation in HeLa cells but not in HeLa/CDDP cells. Transfection of wild-type p53 gene enhanced the cytotoxicity of cisplatin and cisplatin-induced apoptosis in HeLa cells but not in HeLa/CDDP cells, although it caused p53 overexpression in both cell lines. The expression of caspase 1 (interleukin-1β-converting enzyme, ICE) mRNA and the overexpression of bax protein were observed only in HeLa cells. Paclitaxel-induced DNA fragmentation appeared less in HeLa/CDDP cells than in HeLa cells. p53 gene transfection did not affect the extent of DNA fragmentation in either cell line, suggesting that paclitaxel may induce p53-independent apoptosis. These findings suggest that HeLa/CDDP cells may have an acquired phenotype that is resistant to p53-dependent and -independent apoptosis.  相似文献   
100.
Dislodgment of an atrial screw-in pacing lead is quite rare. This report describes a rare case of an atrial screw-in lead dislodgment 10 years after implantation. Although it is an uncommon complication, very late dislodgment can occur postoperatively, and careful follow-up is necessary.  相似文献   
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