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71.
72.
Pancreatic tumors are chemoresistant and malignant, and there are very few therapeutic options for pancreatic cancer, as the disease is normally diagnosed at an advanced stage. Although attempts have been made to develop vaccine therapies for pancreatic cancer for a couple of decades, none of the resultant protocols or regimens have succeeded in improving the clinical outcomes of patients. We herein review vaccines tested within the past few years, including peptide, biological and multiple vaccines, and describe the three sets of criteria used to evaluate the therapeutic activity of vaccines in solid tumors.  相似文献   
73.

Background

Delayed gastric emptying (DGE) is a common complication of pancreaticoduodenectomy. We determined the efficiency of a new reconstruction technique, designed to preserve motilin-secreting cells and maximize the utility of their receptors, in reducing the incidence of DGE after pancreaticoduodenectomy.

Methods

From April 2005 to September 2014, 217 consecutive patients underwent pancreaticoduodenectomy at our institution. Nine patients who underwent total pancreatectomy were excluded. We compared outcomes between patients who underwent pancreaticoduodenectomy with resection of the pyloric ring followed by proximal Roux-en-y gastrojejunal anastomosis (group I, n?=?90) and patients who underwent standard pancreaticoduodenectomy with the orthotopic reconstruction technique (group II, n?=?118).

Results

Overall and clinically relevant rates of DGE were significantly lower in group I than in group II (10 and 2.2 % vs. 57 and 24 %, respectively; p?<?0.05). Length of hospital stay as a result of DGE was shorter in group I than in group II. In univariate analysis, older age, comorbidities, ASA grade 4, operative time, preoperative diabetes, standard reconstruction technique, and postoperative complications were significant risk factors for DGE. In multivariate analysis, older age, standard technique, and postoperative complications were independent risk factors for DGE.

Conclusion

Our new reconstruction technique reduces the occurrence of DGE after pancreaticoduodenectomy.
  相似文献   
74.

Purpose

Sepantronium bromide (YM155) is a hydrophilic quaternary compound that cannot be administered orally due to its low oral bioavailability; it is furthermore rapidly eliminated via the kidneys. The current study aims at improving the pharmacokinetic profile of YM155 by its formulation in immunoliposomes that can achieve its enhanced delivery into tumor tissue and facilitate uptake in neuroblastoma cancer cells.

Methods

PEGylated YM155 loaded liposomes composed of DPPC, cholesterol and DSPE-PEG2000 were prepared via passive film-hydration and extrusion method. Targeted (i.e. immuno-)liposomes were prepared by surface functionalization with SATA modified monoclonal anti-disialoganglioside (GD2) antibodies. Liposomes were characterized based on their size, charge, antibody coupling and YM155 encapsulation efficiency, and stability. Flow cytometry analysis and confocal microscopy were performed on IMR32 and KCNR neuroblastoma cell lines. The efficacy of developed formulations were assessed by in-vitro toxicity assays. A pilot pharmacokinetic analysis was performed to assess plasma circulation and tumor accumulation profiles of the developed liposomal formulations.

Results

YM155 loaded immunoliposomes had a size of 170 nm and zeta potential of ?10 mV, with an antibody coupling efficiency of 60% andYM155 encapsulation efficiency of14%. Targeted and control liposomal formulations were found to have similar YM155 release rates in a release medium containing 50% serum. An in-vitro toxicity study on KCNR cells showed less toxicity for immunoliposomes as compared to free YM155. In-vivo pharmacokinetic evaluation of YM155 liposomes showed prolonged blood circulation and significantly increased half-lives of liposomal YM155 in tumor tissue, as compared to a bolus injection of free YM155.

Conclusions

YM155 loaded immunoliposomes were successfully formulated and characterized, and initial in-vivo results show their potential for improving the circulation time and tumor accumulation of YM155.
  相似文献   
75.
76.
A 13-year-old boy was referred to us for investigation of a giant liver mass, approximately 16 cm in diameter. Sonographically guided percutaneous needle biopsy was performed and histological examination revealed a fetal-type hepatoblastoma. After four courses of chemotherapy, we performed a left hepatic trisegmentectomy. Follow-up computed tomography, 55 months after the surgery, showed a 1-cm tumor on the route of the preoperative needle biopsy. A second laparotomy revealed a peritonealised tumor, which was excised. The histology of this tumor was identical to that of the primary hepatoblastoma. To our knowledge, this is only the second report of needle tract implantation of hepatoblastoma after percutaneous needle biopsy.  相似文献   
77.
Interferon gamma (IFN-γ) is considered a key moderator of cell-mediated immunity. However, little is known about its association with granzyme B, which plays an important role in the effector function of cytotoxic T lymphocytes (CTLs). In the present study, we collected blood samples from 32 healthy adults before and after vaccination with inactivated influenza vaccine in 2017/18 to measure the levels of IFN-γ and granzyme B, which play roles in cell-mediated immunity, and hemagglutination inhibition (HAI) antibody, which plays a role in humoral immunity. The levels of IFN-γ and granzyme B were significantly correlated both before and after vaccination. Furthermore, the post-vaccine fold increases in the IFN-γ and granzyme B levels were significantly correlated. The levels of IFN-γ and granzyme B decreased five months after vaccination in more than half of the subjects who exhibited an increase in IFN-γ and granzyme B at two weeks post-vaccination. This is the first study to investigate the correlation between IFN-γ and granzyme B levels following influenza vaccination. Our study suggests that both IFN-γ and granzyme B can be used as markers of cell-mediated immunity.  相似文献   
78.
Apheresis has been recognized both economically and therapeutically as a novel approach for the treatment of inflammatory diseases, and certain others, which respond poorly to drug therapy. This report is about Adacolumn, an adsorptive carrier based granulocyte and monocyte apheresis device with a volume of 335 mL, filled with about 220 g of cellulose acetate beads of 2 mm diameter as the column adsorptive carriers. Pre- and post-column leukocyte counts have shown that the carriers adsorb about 65% of granulocytes, 55% of monocytes and 2% of lymphocytes from the blood in the column. Additionally, after apheresis, there is a marked decrease in inflammatory cytokines (TNF-alpha, IL-1beta, IL-6 and IL-8) produced by blood leukocytes, together with down-modulation of L-selectin and the chemokine receptor CXCR3. Adacolumn has been used to treat patients with rheumatoid arthritis, ulcerative colitis and HIV infection. Typical apheresis sessions have been 4-10, at a frequency of one or two sessions per week. Treatment of patients with Adacolumn has been associated with very promising efficacy and safety data. Accordingly, in Japan, Adacolumn has been approved by the Ministry of Health for the treatment of ulcerative colitia. Furthermore, Adacolumn met the required quality and safety standards for medical devices and received an EC certification (CE-mark) from TUV in 1999. However, although Adacolumn carriers are very efficient in depleting excess and activated granulocytes and monocytes/macrophages, the clinical efficacy associated with Adacolumn apheresis cannot be fully explained on the basis of reducing granulocytes and monocytes per se. Hence, a long lasting effect on inflammatory cytokine generation, chemokine activities or immunomodulation is likely, but the precise mechanisms involved are not fully understood yet.  相似文献   
79.
Soluble MUC1 (sMUC1) levels are elevated in many MUC1(+) cancers. We and others have shown that MUC1 is expressed on multiple myeloma (MM) plasma cells and B cells. In this study, we measured sMUC1 levels in bone marrow (BM) plasma from 71 MM patients and 21 healthy donors (HDs), and in peripheral blood (PB) plasma from 42 MM patients and 13 HDs using an immunoassay that detects the CA27.29 epitope of MUC1. sMUC1 levels were found to be significantly greater (mean 31.76 U/mL, range 5.69 to 142.48 U/mL) in MM patient BM plasma versus HD BM plasma (mean 9.68 U/mL, range 0.65 to 39.83 U/mL) (P <. 001). Importantly, BM plasma sMUC1 levels were related to tumor burden because sMUC1 levels were significantly higher for MM patients with active disease (34.62 U/mL, range 5.69 to 142.48 U/mL) versus MM patients with minimal residual disease (16.16 U/mL, range 5.7 to 56.68 U/mL) (P =.0026). sMUC1 levels were also elevated in the PB plasma of MM patients (32.79 U/mL, range 4.15 to 148.84 U/mL) versus HDs (18.47 U/mL, range 8.84 to 42.49) (P =.0052). Lastly, circulating immunglobulin M (IgM) and IgG antibodies to MUC1 were measured in 114 MM patients and 31 HDs, because natural antibodies to MUC1 have been detected in patients with other MUC1-bearing malignancies. These studies demonstrated lower levels of circulating IgM (P <.001) and IgG (P =.078) antibodies to MUC1 in MM patients compared with HDs. Our data therefore show that in MM patients, sMUC1 levels are elevated and correlate with disease burden, whereas anti-MUC1 antibody levels are decreased.  相似文献   
80.
To investigate the sensitivity to calcium of erythrocytes in hypertension, changes in the osmotic fragility of erythrocytes following Ca-loading were observed. Washed erythrocytes were obtained from spontaneously hypertensive rats (SHR, Okamoto and Aoki) and age-matched normotensive Wistar Kyoto rats (WKY). Treatment of erythrocytes with Ca-ionophore A23187 and Ca in the medium caused a reduction in the osmotic fragility which correlated with the Ca-concentration. The degree of alteration in the osmotic fragility of erythrocytes was greater in SHR than in WKY. Oral administration of hydralazine to SHR significantly reduced the blood pressure. However, the alterations in the osmotic fragility of erythrocytes secondary to Ca-loading were not different between hydralazine-treated and untreated SHR. In the presence of a Ca-antagonist (verapamil or diltiazem) in the medium, the reduction of the osmotic fragility of erythrocytes caused by Ca-loading was inhibited, and the differences between SHR and WKY were abolished by Ca-antagonists. These results suggest that the greater changes in osmotic fragility of erythrocytes caused by Ca-loading in SHR could be due to a genetic abnormality of Ca-handling by the cell membranes, and that this abnormality might cause an increase in intracellular Ca, which contributes, in part, to the pathogenesis of hypertension.  相似文献   
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