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401.
402.

Background

The standard of care for treatment of localized muscle-invasive bladder cancer (MIBC) is radical cystectomy (RC). The patient’s condition may affect management of MIBC, especially for elderly patients with more comorbid conditions and lower performance status. We retrospectively evaluated the association between clinicopathological data and outcomes for patients with bladder cancer (BCa) treated by RC. We particularly focused on elderly patients (age ≥75 years) with BCa.

Methods

We enrolled 254 patients with BCa who underwent RC and urinary diversion with or without pelvic lymph node dissection. We assessed perioperative complications and clinicopathological data affecting overall survival (OS) after RC.

Results

The incidence of complications was 34.3 %, and that of severe complications (Grade 3–5) was 16.5 %. The elderly group experienced more severe complications (P = 0.042). Median follow-up was 43.0 months (range 1.0–155.6). Five-year OS after RC was 62.7 %. OS after RC was no different for patients aged ≥75 and <75 years (P = 0.983). Multivariate analysis revealed that Eastern Cooperative Oncology Group performance status (ECOG PS) and hemoglobin (Hb) concentration were associated with all-cause mortality. Hb concentration of <12.6 g/dl was an independent predictor of a poor prognosis among elderly patients after RC for BCa. ECOG PS >1 tended to affect OS after RC in this group.

Conclusion

ECOG PS and preoperative Hb concentration were useful for prediction of clinical outcome after RC for elderly patients. This information may aid decision-making in the treatment of elderly patients with MIBC.
  相似文献   
403.
Adenovirus-mediated CTLA4Ig gene transfer has been reported to enhance graft survival in several rodent transplantation models. In this study, we investigated the efficacy of ex vivo and systemic transfer of the CTLA4Ig gene by adenoviral vectors in pancreatic islet allo-transplantation. Islet grafts from BN rats were transplanted to chemically induced diabetic LEW rats. First, ex vivo CTLA4Ig gene transfer into isolated islets was performed prior to transplantation. Survival of transduced grafts under the kidney capsule was slightly prolonged (8.6+/-1.3 days) compared with survival of untransduced grafts (6.7+/-1.2 days); when combined with a short course of FK506, graft survival was further extended (32.6+/-10.7 days vs. 13.7+/-1.0 days with FK506 alone). Secondly, systemic gene transfer was accomplished by intravenous administration immediately after the transplantation procedure. In these animals, islet grafts under the kidney capsule survived longer (15.2+/-3.3 days) than in controls (6.7+/-1.2 days), and when FK506 was administered perioperatively, all the islet grafts survived for more than 100 days. In systemically transduced recipients, the survival of islet grafts transplanted into the liver was not significantly different from that of the grafts placed under the kidney capsule. In order to examine organ-specific immunogenicity, heterotopic BN cardiac grafts were transplanted to LEW rats intra-abdominally, with the virus transferred systemically as in the islet model. In contrast to the islet grafts, all the cardiac grafts were accepted for longer than 100 days, even without FK506 therapy. Finally, the LEW recipients with long-surviving islet or cardiac grafts were re-transplanted with islet grafts from the same donor strain (BN) on day 100. The second islet grafts survived longer than 100 days in half of the cardiac recipients, but consistently failed in the islet recipients. We conclude that in this transplant model, CTLA4Ig gene transfer and FK506 treatment synergistically improved islet graft survival, systemic transfer of the gene was more effective than ex vivo transfer to the islets, and donor-specific tolerance could not be achieved for islet transplantation but was achieved for cardiac transplantation.  相似文献   
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Drug discovery and development is a lengthy and expensive process. Testing new agents in humans at an early stage could reduce the time and costs involved in identifying drugs that are likely to succeed in clinical studies. New guidance has outlined the concept of exploratory clinical trials, which provide important information on a drug's distribution as well as its physiological and pharmacological effects in humans. This strategy reduces the need for preclinical testing by limiting the dose and duration of exposure to a new drug in humans to below those required by the traditional testing of investigational new drugs. Exploratory, first-in-man studies should provide insights into human physiology and pharmacology, identify therapeutic targets relevant to disease and increase our knowledge of a drug's characteristics. Implementation of a new drug also requires the development of useful biomarkers of disease and of the drug's efficacy, as well as sensitive molecular imaging techniques. In this Review, we outline the benefits of exploratory clinical trials, especially in academia, and provide an overview of the experimental tools necessary for rational drug discovery and development.  相似文献   
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Huntington's disease (HD) is a neurodegenerative disorder, with an age-related onset and a progressive development, characterized by choreiform movements. 3-Nitropropionic acid (3NP) induces the inhibition of succinate dehydrogenase (SDH), an increase in oxidative stress and anatomic changes that are related to the pathophysiology of HD. Hence, this toxin is a useful tool to study this pathology. This study compares the effects of 3NP on the development of orofacial dyskinesia (OD) and on SDH activity in young and old mice. Treatment with 3NP (5, 10, 15 or 20 mg/kg once a day, for four days) induced OD in young mice. Old mice presented an increase in the basal level of orofacial movement that was not potentiated by any dose of 3NP. Histochemical analyses showed that old mice presented an increase in the SDH activity. Finally, 3NP induced a decrease in SDH activity at both ages. We suggest that the 3NP-induced OD in young mice is related to the inhibition of SDH activity. In parallel, an enhancement in the basal activity of SDH could be related to the absence of a further increase in the OD presented by old mice treated with 3NP.  相似文献   
409.
The interaction between prostate cancer cells and osteoblasts is essential for the development of bone metastasis. Previously, novel androgen receptor axis-targeted agents (ARATs) were approved for metastatic castration-naïve and non-metastatic castration-resistant prostate cancer (CRPC); both of which are pivotal for investigating the association between the bone microenvironment and tumors. The present study established a novel in vitro 3D microenvironment model that simulated the bone microenvironment of CRPC, and evaluated the drug susceptibility of ARATs and the efficacy of the combination of abiraterone and dutasteride. Green fluorescent protein-transferred C4-2 cells (a CRPC cell line) and red fluorescent protein-transferred human osteoblasts differentiated from human mesenchymal stem cells were co-cultured in chitosan nanofiber matrix-coated culture plates to simulate the 3D scaffold of the bone microenvironment. The growth of C4-2 was quantified using live-cell imaging and the Cell3 iMager duos analysis system. The growth of C4-2 colonies were quantified for a maximum of 30 days. The expression of TGF-β increased and promoted EMT in C4-2 cells co-cultured with osteoblasts, indicating resistance to ARATs. The IC50 of each drug and the combination effect of abiraterone and dutasteride were evaluated using this model. Combination treatment with abiraterone and dutasteride synergistically inhibited the growth of C2-4 colonies compared with individual investigational agents. This could be attributed to the reduction of 3-keto-5α-abiraterone, an androgen receptor agonist. The bone microenvironment model of the present study is unique and useful for evaluating new drug susceptibility testing in prostate cancer cells. This model may help to reveal the unknown mechanisms underlying micro- to clinical bone metastasis in prostate cancer.  相似文献   
410.
Objectives:   To determine candidates for bladder biopsies among Japanese primary non-muscle-invasive bladder cancer patients according to the risk of concomitant carcinoma in situ (CIS).
Methods:   Between January 1992 and August 2006, 173 primary non-muscle-invasive bladder cancer cases underwent transurethral resection of the bladder tumor with bladder biopsies for the detection of CIS. Correlations between biopsy results and preoperative/pathological features were retrospectively analyzed.
Results:   Positive cytology was statistically associated with the presence of concomitant CIS in multivariate analysis ( P  < 0.01). Abnormal cystoscopic appearance outside the tumor almost achieved statistical significance in multivariate analysis among preoperative factors ( P  = 0.06). In our series, one (12.5%) of eight low-risk, 18 (24.7%) of 73 intermediate-risk and 41 (59.4%) of 69 high-risk cases had CIS in normal-looking sites, respectively. In cases with a single papillary tumor and negative cytology, one of 16 (6.3%) had concomitant CIS in their biopsy specimens at the normal-looking sites.
Conclusions:   All non-muscle-invasive bladder cancer patients with positive cytology are candidates for additional random biopsies. Targeted biopsies should be performed for all suspicious areas in the bladder mucosa. Random biopsies should be considered in cases with the macroscopic types of cancer for predicting intermediate- and high-risk cancer.  相似文献   
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