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21.
Bacterial ghosts (BGs) are empty bacterial envelopes of Gram-negative bacteria produced by controlled expression of cloned gene E, forming a lysis tunnel structure within the envelope of the living bacteria. BGs are devoid of cytoplasmic content and possess all bacterial bio-adhesive surface properties in their original state while not posing any infectious threat. BGs are ideally suited as an advanced drug delivery system (ADDS) for toxic substances in tumor therapy. The inner space of BGs can be loaded with either single components or combinations of peptides, drugs or DNA which provides an opportunity to design new types of (polyvalent) drug delivery vehicles. Uptake of BGs loaded with Doxorubicin (Dox) by CaCo2 cells led to effective Dox release from endo-lysosomal compartments and accumulation in the nucleus. Viability and proliferative capacity of the cells were significantly decreased (2–3 orders of magnitude) after internalization of Dox loaded BGs as compared to cells incubated with free Dox. The same effect was observed with leukemia cells. Melanoma cells also revealed a high capability to internalize BGs. These results indicate that BGs are able to target a range of types of cancer. BGs have also been investigated as DNA delivery vectors. Studies show DNA loaded BGs are efficiently phagocytosed and internalized by both professional APCs and tumor cells with up to 82% of cells expressing the plasmid-encoded reporter gene. Our studies with BGs as an ADDS system contribute (i) to optimize drug delivery for the treatment of cancer; (ii) define specific conditions for selection and preparation of BG formulations; (iii) and provide a background for the clinical application of BGs in cancer therapy. 相似文献
22.
幕上星形细胞肿瘤Ki-67抗原表达及其预后作用 总被引:3,自引:2,他引:1
目的 探讨Ki-67抗原在幕上星形细胞肿瘤中的表达及其预后作用。方法 使用S-P免疫组化方法检测82例原发性幕上星形细胞肿瘤标本中Ki-67抗原的表达。单因素使用Kaplan-Meier法,多因素分析使用COX比例风险模型进行预后分析。结果Ki-67 指数在组织学分级GradeⅡ、Ⅲ、Ⅳ中分别为2.86%±1.57%,6.72%±3.95%,8.16%±3.92%(P<0.01)。单因素及多因素分析均提示Ki-67指数是独立的预后因素。在GradeⅡ中,Ki-67指数>2.5%与Grade Ⅲ中Ki-67指数≤2.5%的患者生存期差异无显著性(P>0.05);在GradeⅣ中,Ki-67指数≤2.5%与>2.5%的患者生存期有显著性差异(P<0.01)。结论 Ki-67指数随着各病理级别增高而增高;Ki-67指数>2.5%提示预后较差。在同一病理级别中,Ki-67指数不同,其预后有显著性差异。而部分不同病理级别的患者,随着Ki-67指数的不同,其生存期却无显著差异。联合组织病理检查及Ki-67指数检测有助于更精确地判断预后。 相似文献
23.
H. S. Pollinger M. D. Stegall J. M. Gloor S. B. Moore S. R. Degoey N. A. Ploeger W. D. Park H. S. Pollinger M. D. Stegall J. M. Gloor S. B. Moore S. R. Degoey N. A. Ploeger W. D. Park 《American journal of transplantation》2007,7(4):857-863
The immunologic risk associated with donor-specific antibodies (DSA) against Class II human leukocyte antigens (HLA) in kidney transplant (KTx) recipients is unclear. The aim of this study was to determine the outcome of KTx when DSA was detected only against HLA Class II. To isolate the impact of anti-Class II DSA, we retrospectively analyzed 12 KTx recipients who at baseline had a positive B-cell flow cytometric crossmatch (FXM) and a negative T-cell FXM. Using alloantibody specification analysis, 58.3% (7/12) had DSA against donor Class II and 41.7% had no demonstrable DSA. Biopsy-proven AMR occurred in 57% (4/7) in the Class II(+) group and 0% in the Class II(-) group (p > 0.05). Peritubular capillaries stained positive for C4d in 86% (6/7) of the Class II(+) patients and in 40% (2/5) of the Class II(-) patients (p > 0.05). One patient in the Class II(+) group lost their graft at 3 months to accelerated transplant glomerulopathy, while all other grafts were functioning 3-37 months posttransplant despite the persistence of anti-Class II DSA. We conclude that KTx recipients with clearly defined anti-Class II DSA are at risk for humoral rejection suggesting that desensitization and/or close posttransplant monitoring may be needed to prevent AMR. 相似文献
24.
Studies have demonstrated that lipid rafts ultimately regulate the endocytosis of anthrax toxin via clathrin dependent pathway. Interestingly, GPI-anchored protein rich rafts have also been shown to be transported down to the endocytic pathway to reducing late endosomes. Taking advantage of this parallelism, we tried translating the anthrax toxin natural intoxication mechanism by administering a DNA chimera that encoded protective antigen attached to a mammalian GPI-anchor sequence at its C-terminus (pGPI-PA63). We also designed a chimera that had an additional N-terminal TPA leader sequence (pTPA.GPI-PA63) with an aim to target GPI-PA63 to ER where new CD1 molecules are synthesized. Analysis of antibody titers demonstrated successful priming and potential IgG titers after the first boost. In vitro cell proliferation studies in the presence of GPI-attached PA63 peptides revealed that there was a clonal expansion of CD4+ NK1.1+ helper T cell population which rapidly produced IL-4 in response to T cell receptor ligation. These cells provided direct B cell help that aided IgG formation. Effector responses generated by NKT cells were found to be MHC II-independent and CD1d-restricted. In addition, the group pTPA.GPI-PA63 also displayed low magnitude MHC-II restricted (CD1d-independent) NKT cell and CD4+ T cell helper responses in response to non-GPI attached PA63 peptides which overall resulted in the heightened responses seen for this group. Importantly, DNA vaccination mediated the generation of high avidity neutralizing antibodies that mediated protection against lethal toxin challenge. 相似文献
25.
CD14+单核细胞人类白细胞抗原DR表达率与脓毒症关系的研究 总被引:15,自引:0,他引:15
目的了解烧伤延迟复苏时CDl4^+单核细胞人类白细胞抗原DR(HLA—DR)表达率的变化,分析其与脓毒症的关系。方法选择烧伤面积大于30%TBSA的25例烧伤延迟复苏患者,于伤后1、3、7、14、28d取外周血,其中7例患者住院期间并发脓毒症,于脓毒症发生后连续2d亦取其外周血。另取20例健康体检者外周血作为对照。流式细胞仪检测CD14^+单核细胞HLA.DR表达率,酶联免疫吸附测定法检测血浆中肿瘤坏死因子α(TNF—α)、白细胞介素10(IL-10)的浓度。结果非脓毒症患者伤后1、3、7、14、28dCD14^+单核细胞HLA—DR表达率分别为(15±6)%、(74±5)%、(264±17)%、(284-16)%、(474-16)%,明显低于健康体检者[(924±10)%,P〈0.01];脓毒症患者发生脓毒症后1、2d,该指标亦明显低于健康体检者及非脓毒症患者伤后1、7、14、28d(P〈0.01)。脓毒症患者TNF—d检出率及TNF—α、IL-10浓度,均高于非脓毒症患者和健康体检者(P〈0.05或P〈0.01)。伤后1、7、28d,外周血CD14^+单核细胞HLA—DR表达率与IL—10浓度呈显著负相关(r分别为-0.9963、-0.7459、-0.8474,P〈0.01)。结论烧伤延迟复苏患者免疫功能低下,促炎性介质释放量增加,并发脓毒症时则更为严重。外周血CD14^+单核细胞HLA—DR表达率可作为动态检测患者免疫功能状态的有效指标。 相似文献
26.
F. Giangaspero C. Doglioni M. T. Rivano S. Pileri J. Gerdes H. Stein 《Acta neuropathologica》1987,74(2):179-182
Summary The monoclonal antibody Ki-67, which reacts with cells in the active part of the cell cycle, was used to evaluate immunocytochemically the growth fraction in 22 primary brain neoplasms. The percentage of labelled cells reflected the histological grade of malignancy of each neoplasms. High percentage of Ki-67-positive cells were observed in one choroid plexus carcinoma (60%), one primary melanoma of meninges (40%), three medulloblastomas (40%–50%), one anaplastic astrocytoma and six glioblastomas (10%–40%). One ependymoma had 7% positive cells. Rare positive cells (1%) were present in one pilocytic astrocytoma and one ganglioglioma. Except one negative case, the meningiomas (five cases) had values of positivity ranging from 1% to 6%. Two acoustic schwannomas were negative. These results suggest that immunocytochemical staining with the Ki-67 may be a useful method for measuring the growth fraction in brain neoplasms.Supported in part by Associazione Italiana Ricerca sul Cancro and Ministero Italiano della Pubblica Istruzione 相似文献
27.
Permanent prostate brachytherapy for Japanese men: Results from initial 100 patients with prostate cancer 总被引:1,自引:1,他引:0
Toshikazu Okaneya Shuji Nishizawa Tsuyoshi Nakayama Takayuki Kamigaito Iwao Hashida Noriko Hosaka 《International journal of urology》2007,14(7):602-606
OBJECTIVE: To evaluate the initial results of brachytherapy for prostate cancer with permanent iodine-125 implant in Japan. METHODS: The results obtained with brachytherapy in the initial 100 Japanese patients treated at Nagano Municipal Hospital were reviewed. Patients with a prostate-specific antigen (PSA) level of less than 10 ng/mL and a Gleason's scores of 5, 6, 3 + 4 were classified as having a low risk of recurrence. Patients with a PSA level of 10-20 ng/mL and/or a Gleason's score of 4 + 3 were classified as having an intermediate risk for recurrence. Seventy-eight of the low-risk patients and 19 of the intermediate-risk patients were treated by seed implants alone, or seed implants combined with preceding external radiation, respectively. A total of 53 patients received neoadjuvant hormone therapy. The efficacy and morbidity of brachytherapy were investigated using the serum PSA, International Prostate Symptom Score, quality of life score and uroflowmetry data. RESULTS: The average V100 and D90 obtained by post-implant dosimetry was 94.3 and 113.7%, respectively. Serum PSA decreased gradually after treatment, although it had still not reached a nadir after 1 year. There was little difference of the PSA level between the patients with and without neoadjuvant hormone therapy even at 1 year after seed implantation. There were no PSA biochemical failure or clinical recurrence during the follow-up period. Voiding symptoms worsened until 3 months after treatment, and then gradually improved. Acute urinary retention occurred transiently in one patient (1%). Rectal bleeding and severe diarrhea did not occur. CONCLUSION: Brachytherapy is a feasible and effective option for the treatment of prostate cancer in Japanese men. Brachytherapy may have a different effect in Japanese patients with respect to voiding symptoms. Urinary retention was rare, but voiding symptoms were persistent in Japanese patients. Neoadjuvant hormone therapy deserves investigation to determine whether it can achieve better results, especially in patients with an intermediate risk. 相似文献
28.
H. Iwata T. Otoshi N. Takada T. Murai S. Tamano T. Watanabe Y. Katsura S. Fukushima 《Urological research》1995,23(1):27-32
A series of 8 rat and 16 mouse invasive bladder carcinomas were investigated for the presence of silverstained nucleolar organizer regions (AgNORs) to clarify whether this parameter is applicable to the estimation of their invasive character. With regard to number of AgNORs per cell, neither rat nor mouse carcinomas showed any difference between invasive and noninvasive sites within the same tumor. However, the frequency of cancer cells bearing bizarre dots, irregular in size and shape, was significantly higher at sites of actual invasion. Quantitative data generated using an image analyzer revealed significantly lower values for NOR roundness and significantly larger NOR size in invasive sites than in noninvasive sites in all groups. Double staining for the proliferation marker proliferating cell nuclear antigen (PCNA) and AgNORs was performed on eight rat carcinomas and a close correlation between the two was confirmed. Thus the number of AgNORs in PCNA-positive cells was significantly greater than in PCNA-negative cells. Furthermore, a particularly strong correlation was observed for incidences of PCNA-positive cells and bizarre dots (P<0.01). The quantitative data also demonstrated significant differences in size and shape of dots. It is concluded that AgNORs have diagnostic value for the invasive character of bladder carcinomas. 相似文献
29.
Andries R. Jonkhoff Peter C. Huijgens Willem O. Schreuder Gerrit J. J. Teule Jan J. Heimans 《Journal of neuro-oncology》1993,17(2):155-158
Summary A patient is described with a testicular Non-Hodgkin's Lymphoma (NHL) presenting with panhypopituitarism caused by a hypophyseal localization. A67Gallium scintigraphy showed avid uptake in the hypophyseal region. Obviously67Gallium could reach the tumor, by the intravenous route, which was the reason to treat the patient with intravenous chemotherapy. A complete remission was induced, which seems to be lasting (+ 25 months). As far as we know this is the first report of panhypopituitarism caused by a hypophyseal NHL in the hypophysis and successfully treated by intravenous chemotherapy. 相似文献
30.
用快速双抗体夹心ELISA检测囊虫病人血清中的循环抗原,其阳性率为67.5%;正常人血有的假阳性率为5.33%;包虫、肝吸虫和弓形虫病人血清的交叉反应率分别为6.9%、7.5%和12.5%。结果表明.该法与常规双抗体夹心ELISA相比具有较为敏感、快速、稳定和节省血清、试剂用量的优点,但其特异性有待进一步提高。用快速双抗体夹心ELISA和间接型ELISA检测第1至10疗程囊虫病人血清中的循环抗原和抗体,表明检测循环抗原考核囊虫病人的治疗效果优于检测抗体 相似文献