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91.
92.

Objective

To determine conditional recurrence-free survival (RFS) and progression-free survival (PFS) and improve decision-making toward surveillance protocols and scheduling. Furthermore, evaluating the evolution of predictors for disease recurrence over time, because TaG1 non–muscle-invasive bladder cancer harbors a risk of disease recurrence and progression.

Material and methods

The retrospective multicenter design study includes 1,245 TaG1 bladder cancer patients with median follow-up of 62.7 (interquartile range: 34.3–91.1) months. Conditional RFS and PFS estimates were calculated using the Kaplan-Meier method. Multivariable Cox regression model was calculated proportional for the prediction of recurrence and progression (covariables: age, tumor size, multiple tumors, prior recurrence, and immediate postoperative instillation of chemotherapy).

Results

After 3 months without event, the conditional RFS and PFS (to ≥pT2) rates for 5 additional years without event were 57.5% and 93.4%, respectively. Given a 1-, 2-, 3-, and 5-year survival, the conditional RFS rates for 5 additional years without event improved by +9.8 (67.3%), +5.2 (72.5%), +6.5 (79.0%), +2.0 (81.0%), and +1.0% (82.0%), respectively. In contrast, the 5-year conditional PFS rates were more or less stable with 94.3% after 1 year to 94.1% after 5 years. Multivariable analyses showed decreasing impact of risk parameters on RFS estimates over time. Based on these findings, we suggest a risk stratification to individualize follow-up for intermediate risk TaG1. Main limitation was the retrospective design.

Conclusions

Conditional-survival analyses demonstrates that the patient risk profile changes over time. RFS rates rise with increasing survival whereas PFS rates were stable. The impact of prognostic features decreases over time. Our findings can be used for patient counseling and planning of personalized follow-up.  相似文献   
93.
Soluble oligomeric forms of amyloid beta (Aβ) play an important role in causing the cognitive deficits in Alzheimer’s disease (AD) by targeting and disrupting synaptic pathways. Thus, the present research is directed toward identifying the neuronal pathways targeted by soluble forms and, accordingly, develops alternative therapeutic strategies. The neurotrophin brain‐derived neurotrophic factor (BDNF) is synthesized as a precursor (pro‐BDNF) which is cleaved extracellularly by plasmin to release the mature form. The conversion from pro‐BDNF to BDNF is an important process that regulates neuronal activity and memory processes. Plasmin‐dependent maturation of BDNF in the brain is regulated by plasminogen activator inhibitor‐1 (PAI‐1), the natural inhibitor of tissue‐type plasminogen activator (tPA). Therefore, tPA/PAI‐1 system represents an important regulator of extracellular BDNF/pro‐BDNF ratio. In this review, we summarize the data on the components of the plasminogen activation system and on BDNF in AD. Moreover, we will hypothesize a possible pathogenic mechanism caused by soluble Aβ forms based on the effects on tPA/PAI‐1 system and on the consequence of an altered conversion from pro‐BDNF to the mature BDNF in the brain of AD patients. Translation into clinic may include a better characterization of the disease stage and future direction on therapeutic targets.  相似文献   
94.
95.
The objective of this work was to investigate feasibility of transdermal and dermal delivery of adefovir (9-(2-phosphonomethoxyethyl)adenine), a broad-spectrum antiviral from the class of acyclic nucleoside phosphonates. Transport of 2% adefovir through and into porcine skin and effects of various solvents, pH, and permeation enhancers were studied in vitro using Franz diffusion cell. From aqueous donor samples, adefovir flux through the skin was 0.2-5.4 microg/cm2/h with greatest permeation rate at pH 7.8. The corresponding adefovir skin concentrations reached values of 120-350 microg/g of tissue. Increased solvent lipophilicity resulted in higher skin concentration but had only minor effect on adefovir flux. A significant influence of counter ions on both transdermal and dermal transport of adefovir zwitterion was observed at pH 3.4. Permeation enhancer dodecanol was ineffective, 1-dodecylazepan-2-one (Azone) and dodecyl 2-(dimethylamino)propionate (DDAIP) showed moderate activity. The highest adefovir flux (11.3+/-3.6 microg/cm2/h) and skin concentration (1549+/-416 microg/g) were achieved with 1% Transkarbam 12 (5-(dodecyloxycarbonyl)pentylammonium 5-(dodecyloxycarbonyl)pentylcarbamate) at pH 4. This study suggests that, despite its hydrophilic and ionizable nature, adefovir can be successfully delivered through the skin.  相似文献   
96.
PURPOSE: The aim of this study was to evaluate the thrombogenicity of different peripheral stent types in a standardized in vitro model with fresh human whole blood. MATERIALS AND METHODS: Different stents (N = 77; n = 7 of each of 11 types) were implanted in polyvinyl chloride tubing loops and filled with donor blood samples. After 120 minutes of blood circulation, the thrombin-antithrombin III complex (TAT) levels, beta-thromboglobulin (beta-TG) levels, and platelet counts were assessed. RESULTS: After 2 hours, significant differences were seen. TAT values (+/- SD) with the investigated stents were 31 micro g/mL +/- 20 (control, no stent), 328 micro g/mL +/- 206 (Saxx stent, peripheral medium CrNi31 L), 651 micro g/mL +/- 760 (Palmaz Corinthian Stent, 316 L stainless steel, electropolished), 1,609 micro g/mL +/- 1,264 (Palmaz Corinthian Stent, 316 L stainless steel, not electropolished), 810 micro g/mL +/- 578 (Palmaz Schatz long medium stent), 569 micro g/mL +/- 347 (Smart Nitinol stent), 1,037 micro g/mL +/- 577 (Megalink peripheral stent), 543 micro g/mL +/- 487 (peripheral stent, electropolished), 1,674 micro g/mL +/- 2,057 (peripheral stent, not electropolished), 3,128 micro g/mL +/- 1,812 (SelfX Nitinol stent, polished), 5,897 micro g/mL +/- 2,380 (SelfX Nitinol stent, unpolished), and 1,458 micro g/mL +/- 887 (bridge stent). The platelet count (x1,000/ micro L +/- SD) was 218 +/- 35 (control, no stent), 188 +/- 22 (Saxx stent), 187 +/- 20 (Palmaz Corinthian stent, electropolished), 135 +/- 37 (Palmaz Corinthian stent, not electropolished), 170 +/- 24 (Palmaz Schatz stent), 180 +/- 36 (Smart Nitinol stent), 159 +/- 26 (Megalink peripheral stent), 173 +/- 17 (peripheral stent, electropolished), 133 +/- 51 (peripheral stent, not electropolished), 123 +/- 37 (SelfX Nitinol stent, polished), 52 +/- 27 (SelfX Nitinol stent, unpolished), and 130 +/- 31 (bridge stent). CONCLUSION: This standardized study showed a wide range of platelet activation after stent implantation. Electropolishing clearly reduced the thrombogenicity of the stents.  相似文献   
97.
Disturbance in expression of estrogen receptors together with changing influence of growth factor receptors and apoptosis associated proteins plays a role in breast cancer development and progression. However, immunohistochemical detection and relationships among these proteins were not often considered in relation to breast cancer and a few evaluations of expression provided mismatching results and conclusions. Consequently, we examined by immunohistochemistry the expression of the insulin-like growth factor-I receptor (IGF-IR), estrogen receptor alpha (ERalpha) and apoptosis-associated proteins, Bcl-2 and Bax, in human primary breast cancer, as well as analyzing the relationships among these proteins. The positive immunostaining for IGF-IR, ERalpha, Bcl-2 and Bax was noted in 56, 63.8, 82.8 and 50% of tumors, respectively. We observed that IGF-IR negatively correlated with ERalpha in the group of all tumors and in axillary node negative cancer (p<0.03, p<0.05, respectively), but not in the subgroup of node positive cancer. Expression of ERalpha correlated positively with Bcl-2 and negatively with Bax proteins (p<0.0001, p<0.05, respectively). We did not note significant relationships between IGF-IR and Bcl-2, or IGF-IR and Bax proteins. We found that increased Bax expression was associated with positive lymph node status, pT2 stage and G3 grade of tumors. Knowledge about alterations in the IGF-IR expression and relations of the receptor to other biological factors could help in our understanding of breast cancer biology and the importance of the IGF-IR in cancer progression as well as in effective management of breast cancer.  相似文献   
98.
Regression of pulmonary MALT lymphoma after treatment with rituximab   总被引:4,自引:0,他引:4  
We describe a patient with extranodal (pulmonary) marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) who was refractory to treatment with cytotoxic chemotherapy. After a single four-week course of rituximab she had significant regression of pulmonary lesions and remains progression free 19 months after finishing her treatment. This case report demonstrates the potential efficacy of rituximab as a single therapeutic agent in patients with pulmonary MALT lymphoma.  相似文献   
99.
Point-of-collection oral fluids drug-testing devices are being marketed for a variety of medico-legal purposes where they may complement existing technologies and be used to detect drugs following recent ingestion. To assess the utility of these devices for use in drugged-driving investigations, we performed a laboratory evaluation of four devices and those results were published previously. In the study reported here, two more devices, Oratect(R) (Branan) and Uplink(R) (OraSure), were evaluated for their ability to detect amphetamines, cocaine, opiates, and cannabinoids. An additional device, Drugwipe (Securtec), was evaluated for the detection of cocaine and cannabinoids. Each of the devices was assessed for their ability to meet the manufacturers' claimed cutoff concentrations and to meet cutoffs proposed for federal workplace programs. In general, the Branan and OraSure devices detected amphetamine, methamphetamine, opiates, and cannabinoid metabolite (THC-COOH) well in the concentration ranges approximating those proposed by the Substance Abuse and Mental Health Services Administration (SAMHSA), but all three devices performed poorly in detecting Delta9-tetrahydrocannabinol (THC) at the proposed SAMHSA cutoff. The ability to accurately and reliably detect cocaine was dependent on the individual device, and the Branan and Securetec devices were more effective than OraSure at detecting parent cocaine.  相似文献   
100.
BACKGROUND AND AIM: The European Society of Cardiology initiated the EuroHeart Failure Survey to obtain more data about the quality of care in patients hospitalised with suspected heart failure (HF). The Czech Republic was 1 of the 24 European Society countries included in the survey. The aim of this report is to extend the original follow-up period of 12 weeks out to 4 years to assess mortality. METHODS: All admitted patients were screened according to the EuroHeart Survey Protocol, over a 6-week period in six hospitals in Pilsen, Prague and Brno in the year 2000. Annual mortality and cause of death were obtained from the Prague Institute for Health Statistical Information (UZIS Praha). RESULTS: A total of 2365 patients were screened and about 25% of all admitted patients fulfilled the criteria for HF. About 14% of patients died between admission and the 12-week follow-up, 36% of male and 42% of female patients died during the 4-year follow-up (2000-2003). Cardiovascular diseases were the main causes of death (92%). Deceased patients were significantly older, had lower haemoglobin and total plasma cholesterol level, and had renal insufficiency and higher levels of big endothelin and BNP than the survivors. Mortality risk was increased independently by positive history of previous myocardial infarction OR=2.39 (1.59-3.59), by age OR=1.03 (1.01-1.05) and by plasma creatinine level OR=1.04 (1.01-1.07). Treatment with diuretics and digoxin was associated with a higher risk of death; by contrast, a protective effect of beta-blockers and statins was found in these HF patients. CONCLUSION: Patients with HF were older and had a poor prognosis; approximately one third of the patients will die within 3 years.  相似文献   
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