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1.
ObjectiveTo evaluate the significance of sonographic perinephric fluid collection on the emergent management of patients with acute urinary stone obstruction.MethodsWe conducted a prospective study with retrospective analysis. Since January 2016 through July 2017, patients admitted to our tertiary hospital's emergency department (ED) with suspected symptomatic urinary stones underwent ultrasound evaluation. Images were prospectively interpreted by experienced radiologist who analyzed each case for the following imaging features: hydronephrosis, perinephric fluid and urethral stone identification. The presence and measurements of perinephric fluid were re-evaluated by second radiologist who was blinded for the first reader's measurements. Retrospective analysis was conducted to evaluate for an association between perinephric fluid collection and the following outcome variables: need for analgesics, the number of doses of analgesics and the amount of morphine (mg) in the ED, elevation of creatinine levels, hospitalization and need for urological interventions.ResultsThe need for analgesics, the number of doses of analgesics and the amount of morphine were significantly associated with the presence of perinephric fluid (p < 0.05). The odds ratio for the need for analgesics was 3.8 in the presence of any perinephric fluid, and 8.9 in the presence of moderate/severe perinephric fluid. No other patient outcome variables were found to be significantly associated with the presence of perinephric fluid (p > 0.05).ConclusionsThis study shows a correlation between sonographic evidence of perinephric fluid and more severe pain. Therefore, an emergency physician can consider the evidence of perinephric fluid, in acute urethral stone obstruction, a predictor for more severe pain.  相似文献   
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Introduction: Suramin is a synthetic polysulfonated naphthylurea which has been used for the treatment of African trypanosomiasis and onchocerciasis, but since the mid-1980s has received attention as a possible antiretroviral and antineoplastic agent. Objective: This clinical trial of suramin was undertaken as a phase I/II study in patients with hormone-refractory prostate cancer, with the hypothesis that the intensity of therapy with suramin could be increased significantly if measures were undertaken to maintain the plasma concentrations of the drug under 300 μg/ml. Methods: We report the clinical results of this trial, wherein patients were treated at three different targeted plasma suramin concentrations (275, 215 and 175 μg/ml) for varying periods of time (2, 4 or 8 weeks), with delivery of the drug by continuous intravenous infusion. Results: The major toxicity observed in this trial was neurologic, consisting of a motor and sensory peripheral neuropathy that resulted in both paresis and paralysis of the limbs. Nearly all of this severe (CTEP grade III, IV) neurologic toxicity was observed in the patients treated at a plasma suramin concentration of 275 μg/ml for 4 or more weeks. A single patient treated at 215 μg/ml for 8 weeks developed moderate (CTEP grade III) proximal lower extremity weakness, and no patient treated at 175 μg/ml developed this toxicity. The second most common toxicity observed was infection of the central venous catheter. The overall response rate for all of the evaluable patients was 17% (13 of 75 patients). In addition, prostate-specific antigen (PSA)-defined responses were observed in six patients receiving therapy at 175 μg/ml, but these responses were confounded by cessation of therapy with flutamide during suramin treatment. Conclusions: In summary, although plasma suramin concentrations were maintained below 300 μg/ml, neurologic toxicity nonetheless occurred with high frequency in patients treated at 275 μg/ml for 4 or more weeks. Therapy at 215 and 175 μg/ml was in general well tolerated, but central venous catheter-related infection, as well as the inconvenience and expense of continuous infusional therapy, make this method of drug delivery impractical. Only moderate antitumor activity was observed during this trial, but it is possible that both continuation of flutamide and flutamide withdrawal during suramin therapy confounded the assessment of suramin’s activity in hormone-refractory prostate cancer. Received: 9 June 1995/Accepted: 18 March 1996  相似文献   
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Our inability to associate distant regulatory elements with the genes they regulate has largely precluded their examination for sequence alterations contributing to human disease. One major obstacle is the large genomic space surrounding targeted genes in which such elements could potentially reside. In order to delineate gene regulatory boundaries, we used whole-genome human-mouse-chicken (HMC) and human-mouse-frog (HMF) multiple alignments to compile conserved blocks of synteny (CBSs), under the hypothesis that these blocks have been kept intact throughout evolution at least in part by the requirement of regulatory elements to stay linked to the genes they regulate. A total of 2116 and 1942 CBSs >200 kb were assembled for HMC and HMF, respectively, encompassing 1.53 and 0.86 Gb of human sequence. To support the existence of complex long-range regulatory domains within these CBSs, we analyzed the prevalence and distribution of chromosomal aberrations leading to position effects (disruption of a gene's regulatory environment), observing a clear bias not only for mapping onto CBS but also for longer CBS size. Our results provide an extensive data set characterizing the regulatory domains of genes and the conserved regulatory elements within them.  相似文献   
5.
Previous reports indicate that flutamide withdrawal is associated with PSA declines and tumor shrinkage in selected patients with 'hormone-refractory' prostate cancer. Though the mechanisms underlying this effect are not clear, investigators have hypothesized that these effects are mediated by mutant androgen receptors recognizing hydroxy-flutamide as an androgenic agonist. Such receptors have been well described in the human prostate cancer cell line LNCaP. Despite the finding that the androgen receptor of LNCaP aberrantly recognizes a variety of steroids, including estrogen and progesterone, as androgenic agonists, there are no studies which examine the effect of estrogen antagonists and progesterone antagonist on baseline and androgen-stimulated LNCaP growth. In this report, LNCaP cells were cultured in phenol red-free media using charcoal-stripped sera. As previously reported, flutamide enhanced LNCaP growth and bicalutamide inhibited androgen-stimulated LNCaP proliferation. Neither tamoxifen nor RU486 influenced LNCaP growth (either in the presence or absence of exogenous androgens). From these data we conclude that antagonists of estrogen and progesterone action have no anti-proliferative effect on LNCaP cells and that the mutant androgen receptor expressed in these cells is quite restrictive in the recognition of compounds with antagonistic activity. The clinical implications of these findings are discussed.  相似文献   
6.
The pharmacokinetics of cisplatin administered by continuous hyperthermic peritoneal perfusion (CHPP) was characterized in patients with peritoneal carcinomatosis. Cisplatin was added into the perfusate with escalating doses from 100 mg/m2 to 400 mg/m2. The hyperthermic perfusion was maintained for 90 minutes with a flow rate of 1.5 L/min and a target peritoneal temperature of 42.5 degrees C after a tumor debulking procedure. Samples of both the perfusate and blood were obtained during the perfusion and 30 minutes after the perfusion. Cisplatin plasma and perfusate concentrations were determined by flameless atomic absorption spectrometry with a lower limit of detection of 2 ng/ml and a coefficient of variation (CV) < 10%. Fifty-six patients were enrolled in the study. The mean (+/- SD) percentage of cisplatin present in the perfusate at the completion of perfusion was 27.8% +/- 20% of the total dose. The maximum cisplatin concentrations in the perfusate were 10 times higher than those in plasma. The area under the concentration-time curve (AUC) of the perfusate was 13 times higher than the AUC of plasma. A two-compartment model with an additional peritoneal cavity compartment fits to the data best based on the Akaike information criterion. However, the interpatient variability was considerably high (CV < 100%). In conclusion, cisplatin administered by hyperthermic peritoneal perfusion resulted in a pharmacological advantage by obtaining higher and direct drug exposure to the tumor in the peritoneal cavity while limiting systemic absorption and toxicity. Using a complex two-compartment model, the authors were able to characterize the pharmacokinetics of cisplatin given intraperitoneally via this technique.  相似文献   
7.
PURPOSE: To evaluate changes in epidermal growth factor receptor (EGFR) phosphorylation and its downstream signaling in tumor and surrogate tissue biopsies in patients with metastatic breast cancer treated with erlotinib, an EGFR tyrosine kinase inhibitor, and to assess relationships between biomarkers in tumor and normal tissues and between biomarkers and pharmacokinetics. PATIENTS AND METHODS: Eighteen patients were treated orally with 150 mg/d of erlotinib. Ki67, EGFR, phosphorylated EGFR (pEGFR), phosphorylated mitogen-activated protein kinase (pMAPK), and phosphorylated AKT (pAKT) in 15 paired tumor, skin, and buccal mucosa biopsies (at baseline and after 1 month of therapy) were examined by immunohistochemistry and analyzed quantitatively. Pharmacokinetic sampling was also obtained. RESULTS: The stratum corneum layer and Ki67 in keratinocytes of the epidermis in 15 paired skin biopsies significantly decreased after treatment (P = .0005 and P = .0003, respectively). No significant change in Ki67 was detected in 15 tumors, and no responses were observed. One was EGFR-positive and displayed heterogeneous expression of the receptor, and 14 were EGFR-negative. In the EGFR-positive tumor, pEGFR, pMAPK, and pAKT were reduced after treatment. Paradoxically, pEGFR was increased in EGFR-negative tumors post-treatment (P = .001). Although markers were reduced in surrogate and tumor tissues in the patient with EGFR-positive tumor, no apparent associations were observed in patients with EGFR-negative tumor. CONCLUSION: Erlotinib has inhibitory biologic effects on normal surrogate tissues and on an EGFR-positive tumor. The lack of reduced tumor proliferation may be attributed to the heterogeneous expression of receptor in the EGFR-positive patient and absence of target in this cohort of heavily pretreated patients.  相似文献   
8.
PURPOSE: To compare the preclinical and clinical pharmacokinetic properties of paclitaxel formulated as a Cremophor-free, albumin-bound nanoparticle (ABI-007) and formulated in Cremophor-ethanol (Taxol). EXPERIMENTAL DESIGN: ABI-007 and Taxol were given i.v. to Harlan Sprague-Dawley male rats to determine pharmacokinetic and drug disposition. Paclitaxel pharmacokinetic properties also were assessed in 27 patients with advanced solid tumors who were randomly assigned to treatment with ABI-007 (260 mg/m(2), 30 minutes; n = 14) or Taxol (175 mg/m(2), 3 hours; n = 13), with cycles repeated every 3 weeks. RESULTS: The volume of distribution at steady state and clearance for paclitaxel formulated as Cremophor-free nanoparticle ABI-007 were significantly greater than those for paclitaxel formulated with Cremophor (Taxol) in rats. Fecal excretion was the main elimination pathway with both formulations. Consistent with the preclinical data, paclitaxel clearance and volume of distribution were significantly higher for ABI-007 than for Taxol in humans [21.13 versus 14.76 L/h/m(2) (P = 0.048) and 663.8 versus 433.4 L/m(2) (P = 0.040), respectively]. CONCLUSIONS: Paclitaxel formulated as ABI-007 differs from paclitaxel formulated as Taxol, with a higher plasma clearance and a larger volume of distribution. This finding is consistent with the absence of paclitaxel-sequestering Cremophor micelles after administration of ABI-007. This unique property of ABI-007 could be important for its therapeutic effectiveness.  相似文献   
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The National Vaccine Program Office (NVPO) manages <www.vaccines.gov> and is part of the U.S. Department of Health and Human Services (HHS). Vaccines.gov offers reliable information from the federal government on vaccines, immunizations, and vaccine-preventable diseases. The web site works with the Centers for Disease Control and Prevention (CDC), National Institutes of Health (NIH), Food and Drug Administration (FDA) and many other government agencies to ensure all information on the web site is accurate and relevant. The web site encourages readers to share the information on the site with friends, family, and patients to promote health literacy on vaccines.  相似文献   
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