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71.
Tumors are angiogenesis dependent. Preclinical studies have shown that well-tolerated continuous low dose, i.e. metronomic, chemotherapy can exert significant antiangiogenic effects pe rse and thereby a greater antitumor influence than conventional chemotherapy with high, spaced-out bolus doses. There are however, no means of quantitatively assessing the antiangiogenic effect of chemotherapy in tumors. We therefore used a surrogate tumor-free, non-surgical rat mesentery model and quantitatively studied the dose effect of metronomic treatment with cisplatin, cyclophosphamide, doxorubicin, fluorouracil and paclitaxel on VEGF-A-mediated angiogenesis, a characteristic of tumors. Cyclophosphamide and paclitaxel treatment exerted significant dose-dependent antiangiogenic effects, whereas doxorubicin treatment produced insignificant effects. By contrast, metronomic cisplatin and fluorouracil treatment occasionally significantly stimulated angiogenesis in a dose-dependent, non-linear manner. To our knowledge, this is the first report of metronomic chemotherapy stimulating angiogenesis in vivo. The data suggest that the angiogenic response to cisplatin, cyclophosphamide, fluorouracil and paclitaxel was significantly influenced by the presence of antioxidants in the vehicles or when co-treated with N-acetylcystein, a widely used free-radical scavenger. The data relating to the metronomic scheduling were compared with bolus treatment data for the identical agent formulations in the same experimental model. Cisplatin, cyclophosphamide and paclitaxel caused approximately the same overall, agent-specific angiogenesis-modulating effects following metronomic and bolus treatments. Moreover, apparently secondary delayed effects of chemotherapy affected capillary sprouting. 相似文献
72.
Lindqvist K Holmberg G Peeker R Grenabo L 《Scandinavian journal of urology and nephrology》2006,40(2):113-118
OBJECTIVE: Our extracorporeal shock-wave lithotripsy (ESWL) lithotripter with ultrasound localization technique was replaced in 1999 by a Storz SLX-MX lithotripter with both X-ray and ultrasound detection possibilities. Before replacing our lithotripter, most ureteric stones were treated with ureteroscopy (URS); subsequently, almost all patients underwent ESWL as primary treatment. The aim of this retrospective study was to compare the results of these two treatment strategies in all consecutive patients attending our hospital in 1998 and 2000 for ureteric stone treatment. MATERIAL AND METHODS: The medical records of all patients treated for ureteric stones in 1998 and 2000 were reviewed. In 1998, 173 ureteric stones were treated. Primary treatment was URS in 124 patients, push back/ESWL in 24, ESWL in 21 and open surgery in four. In 2000, 176 ureteric stones were treated: 158 with ESWL and 18 with URS. ESWL or URS monotherapy was defined as ESWL or URS, respectively as the only stone-treatment therapy, with or without the use of a ureteric catheter or nephrostomy tube. Treatment success was defined as a stone-free ureter. RESULTS: In 1998, the success rate for URS monotherapy was 95%, with a retreatment rate (sessions per stone situation) of 1.06. Corresponding figures for ESWL monotherapy in 2000 were 90% and 1.69. All URS patients received general anaesthesia; ESWL patients received opiods. Complication rates were 6% for URS and 3% for ESWL. In the URS group, 4/8 complications were considered to be major. CONCLUSION: ESWL should be considered the first-line treatment for ureteric stones because of its non-invasive nature, lack of a requirement for general anaesthesia and low complication rates. 相似文献
73.
In a randomized, single-blind study, of a pilot nature, the administration of terbutaline sulphate was found to cause significant inhibition of contractions in premature labor. This effect became evident within 30 min when the dosage was 0.1 mg in 1 ml cellulose gel, applied vaginally, and within 2 h when released from a 5-g medicated vaginal polymer ring containing 10% terbutaline sulphate. No generalized effects of the terbutaline were noted (such as increased blood pressure or tachycardia) and the level of terbutaline in peripheral venous blood remained low. Vaginally administered terbutaline can obviously be quickly resorbed, giving a localized effect. Thus applied, terbutaline would appear to offer a number of advantages as regards treatment procedure. 相似文献
74.
Nakanishi T Ozaki Y Blomgren K Tateyama H Sugiura-Ogasawara M Suzumori K 《Molecular human reproduction》2005,11(5):351-355
In the implantation, trophoblasts penetrate maternal decidua by secreting proteases. It has been reported that cathepsins are highly expressed in the mouse villi, and play an important role in normal embryonal growth and decidualization. In this study, we evaluated cathepsins and their endogenous inhibitors, cystatins, in tissue and serum of patients with recurrent miscarriage. Decidua and villi were surgically collected from 22 patients and 12 healthy women. Immunohistochemistry was performed with antibodies against cathepsins, stefin A (cystatin A), stefin B (cystatin B) and cystatin C. The concentrations of cathepsins, stefins and cystatin C were measured by Enzyme-linked immunosorbent assay. In addition, we measured the serum level of cystatin C in 85 Japanese women with recurrent miscarriage. Staining of cathepsin B, D, H, L, stefin B and cystatin C was observed in the cytoplasm of epithelial cells in decidua. Stefin A was expressed on the surface of the trophoblast. The concentration of cathepsin B and H in patients' decidua was significantly higher than in control individuals. The serum level of cystatin C was significantly lower in patients than in control individuals. Our findings suggest that the regulation of the cathepsin-cystatin system may play an important role in patients with recurrent miscarriage. 相似文献
75.
Silverplats K Lind B Zoega B Halldin K Gellerstedt M Rutberg L Brisby H 《Acta orthopaedica》2011,82(2):198-203
Background and purpose
Health-related quality of life (HRQoL) instruments have been of increasing interest for evaluation of medical treatments over the past 10–15 years. In this prospective, long-term follow-up study we investigated the influence of preoperative factors and the change in HRQoL over time after lumbar disc herniation surgery.Methods
117 patients surgically treated for lumbar disc herniation (L4-L5 or L5-S1) were evaluated with a self-completion HRQoL instrument (EQ-5D) preoperatively, after 2 years (96 patients) and after 7 years (89 patients). Baseline data (age, sex, duration of leg pain, surgical level) and degree of leg and back pain (VAS) were obtained preoperatively. The mean age was 39 (18–66) years, 54% were men, and the surgical level was L5-S1 in 58% of the patients. The change in EQ-5D score at the 2-year follow-up was analyzed by testing for correlation and by using a multiple regression model including all baseline factors (age, sex, duration of pain, degree of leg and back pain, and baseline EQ-5D score) as potential predictors.Results
85% of the patients reported improvement in EQ-5D two years after surgery and this result remained at the long-term follow-up. The mean difference (change) between the preoperative EQ-5D score and the 2-year and 7-year scores was 0.59 (p < 0.001) and 0.62 (p < 0.001), respectively. However, the HRQoL for this patient group did not reach the mean level of previously reported values for a normal population of the same age range at any of the follow-ups. The changes in EQ-5D score between the 2- and 7-year follow-ups were not statistically significant (mean change 0.03, p = 0.2). There was a correlation between baseline leg pain and the change in EQ-5D at the 2-year (r = 0.33, p = 0.002) and 7-year follow-up (r = 0.23, p = 0.04). However, when using regression analysis the only statistically significant predictor for change in EQ-5D was baseline EQ-5D score.Interpretation
Our findings suggest that HRQoL (as measured by EQ-5D) improved 2 years after lumbar disc herniation surgery, but there was no further improvement after 5 more years. Low quality of life and severe leg pain at baseline are important predictors of improvement in quality of life after lumbar disc herniation surgery.The natural course of events after sciatic pain originating from lumbar disc herniation is most often favorable, but surgery is frequently performed in patients with persistent sciatic pain (Atlas et al. 2005, Stromqvist et al. 2008). There are many different ways to evaluate the outcome after disc herniation surgery, and traditionally the treatment effects have been studied by patient-reported pain scales (VAS), return to work, functional status, radiological/imaging outcomes, and by evaluation of complication rates (Loupasis et al. 1999, Vucetic et al. 1999, Gerszten et al. 2006, Peul et al. 2007).In recent years, outcome based on patients'' own assessments, such as satisfaction with treatment (Ronnberg et al. 2007), patients'' global assessment (Hagg et al. 2002), or health-related quality of life (HRQoL) (Jansson et al. 2005, Kagaya et al. 2005, Gerszten et al. 2006, Heider et al. 2007, Veresciagina et al. 2007, Jansson et al. 2009, Stromqvist et al. 2009) have gained increasing interest in spinal surgery. Furthermore, good correlations have been shown between patients'' assessments and validated objective outcome scores (Hagg et al. 2002, Ronnberg et al. 2007).The aim of using HRQoL instruments is to measure the influence of a disorder/disease on a patient''s daily life and activities; they have come to be used frequently to evaluate outcome after different types of surgery (Rampersaud et al. 2008, Rolfson et al. 2009). The most popular health status instruments are the EuroQol-5 Dimension (EQ-5D) (Dolan 1997) and the 36-Item Short-Form Health Survey (SF-36) (Ware et al. 1995), which are both patient-based questionnaires. Since these instruments are not specific for a certain condition, they allow comparisons of the effects of different treatment modalities for a specific condition and also the individual effects of different medical conditions on daily life. The EQ-5D instrument can also be used in cost-effectiveness evaluations.The main aim of the present prospective follow-up study was to follow the postoperative development of HRQoL after lumbar disc herniation surgery. Secondary aims were to evaluate potential relationships between preoperative factors and the development of HRQoL and to investigate differences between 2-year HRQoL and 7-year HRQoL (range: 5–8 years). The primary outcome variable was change in EQ-5D. 相似文献76.
Natural killer (NK) cells express inhibitory receptors for major histocompatibility complex (MHC) class I. If self-MHC is down-regulated or absent, lack of inhibition triggers "missing self" killing. NK cells developing in the absence of MHC class I are hypo-responsive, demonstrating that MHC class I molecules are required for NK-cell education. Here, we show that the number and the type of MHC class I alleles that are present during NK-cell education quantitatively determine the frequency of responding NK cells, the number of effector functions in individual NK cells, and the amount of interferon-gamma production in NK cells of specific Ly49 subsets. A relationship between the extent of inhibitory signals during education and functional responsiveness was corroborated by an enhanced probability of NK cells expressing more than one inhibitory receptor for a single host self-MHC class I allele to degranulate after activation. Our data suggest that the capacity of an individual NK cell to respond to stimulation is quantitatively controlled by the extent of inhibitory signals that are received from MHC class I molecules during NK-cell education. 相似文献
77.
OBJECTIVES: Evaluation of the performance of the EMIT 2000 Tacrolimus assay on the Abbott Architect c8000 analyzer. DESIGN AND METHODS: Imprecision studies were performed and patient samples were assayed by EMIT assay and by LC-MS/MS. RESULTS: Limit of quantification was established at 2.8 microg/L. A positive bias of 17.5% between results measured on EMIT and on LC-MS/MS was detected. CONCLUSIONS: EMIT 2000 Tacrolimus assay is suitable for automated analyses of Tacrolimus on the Architect c8000. 相似文献
78.
79.
Slemmer JE Zhu C Landshamer S Trabold R Grohm J Ardeshiri A Wagner E Sweeney MI Blomgren K Culmsee C Weber JT Plesnila N 《The American journal of pathology》2008,173(6):1795-1805
Traumatic brain injury (TBI) consists of two phases: an immediate phase in which damage is caused as a direct result of the mechanical impact; and a late phase of altered biochemical events that results in delayed tissue damage and is therefore amenable to therapeutic treatment. Because the molecular mechanisms of delayed post-traumatic neuronal cell death are still poorly understood, we investigated whether apoptosis-inducing factor (AIF), a pro-apoptotic mitochondrial molecule and the key factor in the caspase-independent, cell death signaling pathway, plays a causal role in neuronal death following TBI. Using an in vitro model of neuronal stretch injury, we demonstrated that AIF translocated from mitochondria to the nucleus of neurons displaying axonal disruption, chromatin condensation, and nuclear pyknosis in a caspase-independent manner, whereas astrocytes remained unaffected. Similar findings were observed following experimental TBI in mice, where AIF translocation to the nucleus coincided with delayed neuronal cell death in both cortical and hippocampal neurons. Down-regulation of AIF in vitro by siRNA significantly reduced stretch-induced neuronal cell death by 67%, a finding corroborated in vivo using AIF-deficient harlequin mutant mice, where secondary contusion expansion was significantly reduced by 44%. Hence, our current findings demonstrate that caspase-independent, AIF-mediated signaling pathways significantly contribute to post-traumatic neuronal cell death and may therefore represent novel therapeutic targets for the treatment of TBI. 相似文献
80.
Titanji K Sammicheli S De Milito A Mantegani P Fortis C Berg L Kärre K Travi G Tassandin C Lopalco L Rethi B Tambussi G Chiodi F 《Immunology》2008,123(2):164-170
Human natural killer (NK) (CD3- CD56+) cells can be divided into two functionally distinct subsets, CD3- CD56(dim) and CD3- CD56(bright). We analysed the distribution of NK cell subsets in primary and chronic human immunodeficiency virus-1 (HIV-1) infection, to determine if HIV infection stage may influence the subset distribution. In primary infection, contrary to chronic infection, the CD3- CD56(dim) subset was expanded compared to healthy controls. We also studied the effect of antiretroviral therapy administered early in infection and found that NK cell subset distribution was partially restored after 6 months of antiretroviral therapy in primary infection, but not normalized. Recently, NK cells have been divided into CD27- and CD27+ subsets with different migratory and functional capacity and CD27-mediated NK cell activation has been described in mice. We therefore investigated whether CD27 and/or CD70 (CD27 ligand) expression on NK cells, and thus the distribution of these novel NK subsets, was altered in HIV-1-infected patients. We found up-regulated expression of both CD27 and CD70 on NK cells of patients, resulting in higher proportions of CD27(high) and CD70(high) NK cells, and this phenomenon was more pronounced in chronic infection. Experiments conducted in vitro suggest that the high interleukin-7 levels found during HIV-1 infection may participate in up-regulation of CD70 on NK cell subsets. Imbalance of NK cell subsets and up-regulated expression of CD27 and CD70 initiated early in HIV-1 infection may indicate NK cell activation and intrinsic defects initiated by HIV-1 to disarm the innate immune response to the virus. 相似文献