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41.
Anti-angiogenic effects of Hypericin-photodynamic therapy in combination with Celebrex in the treatment of human nasopharyngeal carcinoma 总被引:4,自引:0,他引:4
Photodynamic therapy (PDT) is being investigated as an alternative treatment modality in cancer treatment. It has been shown to induce tumor hypoxia and upregulation of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF). The objective of this study was to improve in vivo tumor growth control of nasopharyngeal carcinoma (NPC), treated at a subcurative dosage by using a combination of Hypericin-PDT and COX-2 inhibitor, Celebrex (CX). The effect of an initial CX dose at 6- and 24-h post-PDT was investigated simultaneously. It was observed that hypoxic NPC/CNE2 cells upregulate both COX-2 and VEGF A genes in vitro. In vivo studies, down-regulation of COX-2 and hypoxia inducible factor-1alpha (HIF-1alpha) genes at 24-h post-PDT and bulk tumor ablation at 48-h post-PDT was observed. However, 24-28 days later regrowth was observed. In a combination treatment, 1st CX dose at 6-h post-PDT had the highest tumor control in which tumors were 相似文献
42.
The immunity of a combined DNA vaccine of HSV-2 glycoproteins B2 (gB2) and D2 (gD2) genes in comparison to individual vaccines was studied with regard to protecting against the HSV infection. Two recombinant DNA vaccines of the pHS2-gB2 or pHS2-gD2 were constructed and formulated. The neutralizing antibody titers appeared higher in the B2:D2 gene cocktail-vaccinated mice than that of the individual B2 or D2 gene-vaccinated group alone, and the positive KOS control induced higher titer of the neutralizing antibody than combined or individual gene vaccines. The mock-immunized mice failed to induce enough. The ranks for the CTL activity and the protection rates against the lethal intravaginal challenge were shown as KOS>B2:D2 cocktail>D2>B2 gene vaccines. The vaginal external diseases in the B2:D2 or D-vaccinated mice were significantly reduced against the challenging dosages. The virus titers in the vaginal secretions of the vaccinated mice significantly reduced with time, and the B2:D2 gene vaccine decreased more than each individual vaccine alone. It can be concluded that the cocktailed vaccines are more effective in the humoral and cellular immune responses in the mice, and in the protection of the mice against the intravaginal challenging dosages when compared with individual gene vaccines. All the DNA vaccines failed to block the latent infection in sensory nerves. 相似文献
43.
Jo EK Wang Y Kanegane H Futatani T Song CH Park JK Kim JS Kim DS Ahn KM Lee SI Park HJ Hahn YS Lee JH Miyawaki T 《Journal of human genetics》2003,48(6):322-326
Mutations in the Bruton's tyrosine kinase (BTK) gene are responsible for X-linked agammaglobulinemia (XLA). We identified BTK mutations in six patients with presumed XLA from unrelated Korean families. Four out of six mutations were novel: two missense
mutations (P565T, C154Y), a point mutation in a splicing donor site (IVS11+1G>A), and a large deletion (a 6.1-kb deletion
including BTK exons 11–18). The large deletion, identified by long-distance PCR, revealed Alu-Alu mediated recombination extended from an Alu sequence in intron 10 to another Alu sequence in intron 18, spanning a distance of 6.1 kb. The two known mutations consisted of one missense (G462D) mutation,
and a point mutation in a splicing acceptor site (IVS7−9A>G). This study suggests that large genomic rearrangements involving Alu repeats are few but an important component of the spectrum of BTK mutations. 相似文献
44.
Summary: The latent thermal cationic initiators, benzyl‐2,5‐dimethylpyrazinium hexafluoroantimonate (BDPH) and benzyl‐2‐ethylpyrazinium hexafluoroantimonate (BEPH), were synthesized to investigate the effect of substituted alkyl groups on cure and dynamic mechanical behaviors of difunctional epoxy system. The cure temperature and activation energy of the diglycidyl ether of bisphenol A (DGEBA)/BDPH were higher than those of the DGEBA/BEPH, resulting from the steric hindrance of the substituted groups. The cross‐linking density of the DGEBA/BDPH was higher than that of the DGEBA/BEPH, whereas the Tg's of both specimens are similar. This may be explained by the free volume and the intermolecular hydrogen bonding induced by the hydrogen of the substituted methyl groups. Consequently, the position and number of the substituted groups of the latent thermal initiator were very important in the control of the latent thermal and dynamic mechanical behaviors of the epoxy resin.
45.
Loss of heterozygosity on chromosomes 3p,8p,9p and 17p in the progression of squamous cell carcinoma of the larynx 总被引:4,自引:0,他引:4
Yoo WJ Cho SH Lee YS Park GS Kim MS Kim BK Park WS Lee JY Kang CS 《Journal of Korean medical science》2004,19(3):345-351
Previous molecular genetic studies of laryngeal squamous cell carcinoma (SCC)have shown certain chromosomal regions with recurring alterations. But studies of sequential molecular alterations and genetic progression model of laryngeal SCC have not been clearly defined. To identify the chromosomal alterations associated with the carcinogenesis of laryngeal SCC, we analyzed genomic DNA from microdissected squamous metaplasia, squamous dysplasia, invasive SCC, and metastatic carcinoma samples from 22 laryngeal SCC patients for loss of heterozygosity (LOH) at microsatellite loci. Ten microsatellite markers on chromosome 3p, 8p, 9p, and 17p were used. LOH at 9p21 was observed in the all stages including squamous metaplasia, squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 17p13.1, 3p25 and 3p14.2 was observed from the squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 8p21.3-p22 was observed mainly from the invasive SCC and metastatic carcinoma. The results suggest that 9p21 in the early event, 17p13.1, 3p25 and 3p14.2 in the intermediate event and 8p21.3- p22 in the late event may be involved in the laryngeal carcinogenesis. 相似文献
46.
Ontogenetic transition in fetal wound transforming growth factor-beta regulation correlates with collagen organization 总被引:2,自引:0,他引:2 下载免费PDF全文
Soo C Beanes SR Hu FY Zhang X Dang C Chang G Wang Y Nishimura I Freymiller E Longaker MT Lorenz HP Ting K 《The American journal of pathology》2003,163(6):2459-2476
Fetal rat skin transitions from scarless fetal-type repair to adult-type repair with scar between day 16 (E16) and day 18 (E18) of gestation (term = 21.5 days). Deficient transforming growth factor (TGF)-beta 1 and -beta 2 injury response has been proposed as a mechanism for scarless fetal-type repair. However, previous fetal studies have inconsistently reported the degree of TGF-beta induction after injury. To minimize developmental variables in fetal versus adult TGF-beta regulation, we narrowed our study to wounded fetal animals. We hypothesize that TGF-beta ligand and receptor expression will be differentially regulated during the transition from early gestation (E16) wounds manifesting scarless fetal-type repair to late gestation (E19) wounds manifesting adult-type repair with scar. In this study, decreased and rapidly cleared TGF-beta 1 and -beta 2 expression accompanied by increased and prolonged TGF-beta 3 levels in wounded E16 animals correlated with organized collagen deposition. In contrast, increased and prolonged TGF-beta 1 and -beta 2 expression accompanied by decreased and delayed TGF-beta 3 expression in wounded E19 animals correlated with disorganized collagen architecture. Similarly, expression of TGF-beta receptors type I and II were also increased or prolonged in E19 animals. Our results implicate increased TGF-beta 1, -beta 2, and decreased TGF-beta 3 expression, as well as increased type I and II receptor expression in late gestation fetal scar formation. 相似文献
47.
Kim MS Seo KS Seong HS Cho SH Lee HB Hong KD Kim SK Khang G 《Bio-medical materials and engineering》2005,15(3):229-238
p-Carboxyphenoxy propane (CPP) prepolymer consisting of 4 units and sebacic acid (SA) prepolymer consisting of about 10 units were synthesized by reacting CPP and SA in the presence of excess acetic anhydride, respectively. Polyanhydride, poly(CPP-SA) copolymers were copolymerized by a melt polycondensation process with a mixture of CPP and SA prepolymer. Copolymers of average molecular weight up to 110,000 g/mol were achieved. The crystallinity of poly(CPP-SA) copolymers was decreased by the addition of the CPP homopolymer segment to SA homopolymer. Poly(CPP-SA) copolymers gradually degraded for period of 10 days. No large difference of weight loss observed according to molecular weight variation of poly(CPP-SA) copolymers. BCNU release from wafers fabricated by poly(CPP-SA) showed a sustained release pattern with no initial burst and delay of drug release. 相似文献
48.
Associations of serum TRAIL concentrations, anthropometric variables, and serum lipid parameters in healthy adults 总被引:1,自引:0,他引:1
To investigate the relationships of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), anthropometric variables, and lipid parameters, we measured serum TRAIL concentrations, body mass index (BMI), total body fat (TBF), and serum lipid profiles in 207 healthy adults. There were no significant differences in serum TRAIL concentrations between men and women, nor between elderly persons and middle-aged subjects. However, men with TBF 16.4 kg (75th per centile) exhibited significantly higher serum TRAIL concentrations than those with TBF 11.2 kg (25th per centile) (69.7 +/- 15.1 pg/ml vs 50.2 +/- 14.3 pg/ml, p < 0.05). Serum TRAIL concentration averaged 76.2 +/- 16.1 pg/ml in women with low-density lipoprotein cholesterol (LDL-C) 165 mg/dl (75th per centile), which was significantly above the values (53.1 +/- 12.9 pg/ml, p < 0.05) in those with LDL-C 117 mg/dl (25th per centile), although no differences were observed on the basis of TBF (75th percentile vs 25th percentile). Serum TRAIL concentrations correlated significantlywithTBF (r = 0.31, p < 0.05) and lean body mass (r = -0.26, p <0.05) in men and LDL-C (r = 0.32, p < 0.05) and total cholesterol (r = 0.21, p < 0.05) in women. In conclusion, serum TRAIL concentrations are associated with serum lipid levels and body adiposity in healthy adults, but are unrelated to a subject's age or gender. 相似文献
49.
Induction of immune responses in patients with B-cell lymphoma against the surface-immunoglobulin idiotype expressed by their tumors. 总被引:28,自引:0,他引:28
L W Kwak M J Campbell D K Czerwinski S Hart R A Miller R Levy 《The New England journal of medicine》1992,327(17):1209-1215
BACKGROUND. The idiotypic determinants of the surface immunoglobulin of a B-cell lymphoma can serve as a clonal tumor-specific marker, which may have implications for immunotherapy. We sought to determine whether idiotype-specific immune responses against this autologous antigen could be induced in patients with B-cell lymphoma. METHODS. Nine patients were selected who had minimal residual disease or a complete remission after chemotherapy. Each received a series of subcutaneous injections of the immunoglobulin derived from his or her tumor cells (immunoglobulin-idiotype protein), which had been conjugated to a protein carrier and mixed with an immunologic adjuvant. RESULTS. In seven of the nine patients the injections induced sustained idiotype-specific immunologic responses of the humoral type (two patients), the cell-mediated type (four patients), or both (one patient). The use of an adjuvant was essential for these immune responses. The induced antibodies bound specifically to autologous immunoglobulin idiotype, inhibited the binding of murine monoclonal antiidiotype antibodies, and bound autologous tumor cells. Cell-mediated responses were demonstrated by the specific proliferation of immune peripheral-blood mononuclear cells to the soluble immunoglobulin-idiotype protein in vitro. The tumors of both of the patients with measurable disease regressed completely. Toxicity associated with the vaccine was minimal and consisted only of mild reactions at the site of intramuscular injection. CONCLUSIONS. These results demonstrate that autologous immunoglobulin idiotype can be formulated into an immunogenic, tumor-specific antigen in humans with B-cell lymphoma, and they provide the background for large-scale trials of active specific immunotherapy of this disease. 相似文献
50.
Park SH Park KS Park HG Lee HJ Seo JK Lee KH Kim DH Lee WH Lee CW Hong MK Park SW Park SJ 《Journal of Korean medical science》2003,18(4):585-588
This report describes an uncommon case of hypertrophic obstructive cardiomyopathy (HOCM) accompanying infundibular stenosis of the right ventricle treated by alcohol ablation therapy, in a 28-yr-old male patient presenting with dyspnea on exertion. HOCM with infundibular stenosis was detected by echocardiogram and cardiac catheterization and patient has dynamic obstructions of both ventricular outflow tracts. We performed alcohol ablation therapy to improve clinical symptoms and to relieve dynamic obstructions of both ventricular outflow tracts. This is the first case in which HOCM with infundibular stenosis of the right ventricle was treated by alcohol ablation therapy. 相似文献