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191.
OBJECTIVE: To evaluate cross reactivity between sulfonamide antimicrobials and celecoxib in patients with histories of allergies to sulfonamide antimicrobials. METHODS: Immunocompetent patients with a history of sulfonamide antimicrobial allergy who were being considered for therapy with celecoxib were prospectively enrolled. Sulfamethoxazole and trimethoprim skin prick and intradermal testing and/or an in vitro lymphocyte toxicity assay were performed. If skin testing was negative, an oral challenge with sulfamethoxazole and trimethoprim was performed. Oral challenges with celecoxib were administered to all patients. RESULTS: Twenty-eight immunocompetent patients (26 female; mean age 60 years) were evaluated. History of sulfonamide antimicrobial allergy included urticaria (n = 7), cutaneous eruptions (n = 9), and other (n = 12). Four of the 28 patients who were skin prick tested were positive to sulfamethoxazole and two of the ten patients who underwent in vitro testing were positive to sulfamethoxazole. All 28 patients were administered celecoxib and tolerated the medication. Phone call follow up in 25 patients disclosed that 15 patients continued to take celecoxib, while five patients did not take celecoxib following the oral challenge, and five discontinued celecoxib due to adverse effects, lack of drug efficacy or physician preference. CONCLUSIONS: Confusion exists regarding the potential for cross reactivity between sulfonamide antimicrobials and other sulfonamide-containing compounds. The six sulfonamide-allergic patients tolerated celecoxib uneventfully. This pilot study supports the hypothesis that the potential for cross-reactivity between celecoxib and sulfonamide antimicrobials appears to be low. However, further investigations are required to confirm this.  相似文献   
192.
Behavioral sensitization, the progressive and enduring enhancement of certain behaviors following repetitive drug use, is mediated in part by dopaminergic pathways. Increased locomotor response to drug treatment, a sensitizable behavior, is modulated by an opposing balance of dopamine receptor subtypes, with D1/D2 dopamine receptor stimulation increasing and D3 dopamine receptor activation inhibiting amphetamine-induced locomotion. We hypothesize that tolerance of D3 receptor locomotor inhibition contributes to behavioral sensitization. In order to test the hypothesis that expression of behavioral sensitization results in part from release of D3 receptor-mediated inhibition, thereby resulting in decreased response to D3 receptor agonists, we examined the effect of repetitive amphetamine administration on the behavioral response to the D3 receptor preferring agonists 7-OH-DPAT and PD 128907. D3-selective effects have recently been described for both drugs at a low dose. At 1 week following completion of a repetitive treatment regimen, amphetamine-pretreated rats displayed a decreased response to D3-selective doses of both 7-OH-DPAT and PD 128907, when compared to animals receiving saline pretreatment. Moreover, in addition to the quantitative alteration in response, there was a change in the inter-relation between response to amphetamine and D3 agonist. A highly significant inverse relation between locomotor inhibitory response to PD 128907 and the locomotor-stimulant response to amphetamine was observed prior to amphetamine treatment. In contrast, 10 days following repetitive amphetamine treatment, the relation between response to PD 128907 and amphetamine was not detected. The observed behavioral alteration could not be accounted for by changes in D3 receptor binding in ventral striatum. These findings suggest a persistent release of D3 receptor-mediated inhibitory influence contributes to the expression of behavioral sensitization to amphetamine.  相似文献   
193.
Biochemical markers applicable to the ovariectomized rat model can provide important tools for studying the bone remodeling process in this animal model of postmenopausal osteoporosis. We describe the development and application of two biochemical markers, a C-telopeptide (of type-I collagen) enzyme-linked immunosorbent assay (ELISA) for measuring bone resorption and an osteocalcin radioimmunoassay (RIA) for measuring bone formation in rat serum. The C-telopeptide ELISA is based on an affinity purified polyclonal antibody generated against human sequence DFSFLPQPPQEKAHDGGR. The antibody epitope involves amino acid sequence, which is similar in rat and human carboxyl terminal peptide of type-I (alpha 1) collagen. Sensitivity of the ELISA was 0.3 ng/ml. The averaged intra- and interassay variation was CV <7%. Averaged dilution and spiked recoveries were 91% and 105%, respectively. The second marker developed is a synthetic peptide-based osteocalcin RIA, which does not require isolation and purification of intact osteocalcin from rat bone. Osteocalcin antiserum used in the RIA was generated in rabbits against a synthetic peptide comprising amino acids 33–49 of the rat osteocalcin sequence. The sensitivity of the RIA was 0.15 ng/ml of peptide. The averaged intra (n = 10) and interassay variations for two controls were CV <9% and 12%, respectively. The averaged dilution and spiked recoveries were 99.6%. In vivo validation of the C-telopeptide ELISA and osteocalcin RIA was performed in an ovariectomized (OVX) rat model. In 12-week-old OVX Sprague Dawley rats, the C-telopeptide and osteocalcin concentrations were approximately 65% and 40%, respectively, higher than the sham group. Estradiol repletion significantly lowered the C-telopeptide and osteocalcin concentration to the levels of the sham group. In addition, changes in serum C-telopeptide concentration correlated negatively with trabecular BMD measured by pQCT (r =−0.51, P < 0.001). In conclusion, the C-telopeptide ELISA and osteocalcin RIA exhibited required sensitivity, accuracy, and adequate discriminatory power to be used for measuring bone resorption and bone formation in the ovariectomized rat model. Received: 20 August 1999 / Accepted: 5 January 2000  相似文献   
194.
PURPOSE: To assess oregovomab as consolidation treatment of advanced ovarian cancer and refine the immunotherapeutic strategy for subsequent study. PATIENTS AND METHODS: Patients with stage III/IV ovarian cancer who had a complete clinical response to primary treatment were randomly assigned to oregovomab or placebo administered at weeks 0, 4, and 8, and every 12 weeks up to 2 years or until recurrence. The primary end-point was time to relapse (TTR). RESULTS: One hundred forty-five patients were treated with oregovomab (n = 73) or placebo (n = 72). For the population overall, median TTR was not different between treatments at 13.3 months for oregovomab and 10.3 months for placebo (P =.71). Immune responses were induced in most actively treated patients. This was associated with prolonged TTR. Quality of life was not adversely impacted by treatment. Adverse events were reported with similar frequency in oregovomab and placebo groups, indicating a benign safety profile. A long-term survival follow-up is ongoing. Cox analysis of relapse data identified significant factors: performance status, CA-125 before third cycle, and baseline CA-125. Further evaluation identified a subpopulation with favorable prognostic indicators designated as the successful front-line therapy (SFLT) population. For the SFLT population, TTR was 24.0 months in the oregovomab group compared with 10.8 months for placebo (unadjusted hazard ratio of 0.543 [95% CI, 0.287 to 1.025]), a hypothesis-generating observation. CONCLUSION: Consolidation therapy with oregovomab did not significantly improve TTR overall. A set of confirmatory phase III studies has been initiated to determine whether the SFLT population derives benefit from oregovomab treatment.  相似文献   
195.
PURPOSE: Preclinical and clinical studies have demonstrated that inhibition of prenylation can radiosensitize cell lines with activation of Ras and produce clinical response in patients with cancer. The aim of this study was to determine the maximally tolerated dose of the dual farnesyltransferase and geranylgeranyltransferase I inhibitor L-778,123 in combination with radiotherapy for patients with locally advanced pancreatic cancer. EXPERIMENTAL DESIGN: L-778,123 was given by continuous intravenous infusion with concomitant radiotherapy to 59.4 Gy in standard fractions. Two L-778,123 dose levels were tested: 280 mg/m2/day over weeks 1, 2, 4, and 5 for dose level 1; and 560 mg/m2/day over weeks 1, 2, 4, 5, and 7 for dose level 2. RESULTS: There were no dose-limiting toxicities observed in the eight patients treated on dose level 1. Two of the four patients on dose level 2 experienced dose-limiting toxicities consisting of grade 3 diarrhea in one case and grade 3 gastrointestinal hemorrhage associated with grade 3 thrombocytopenia and neutropenia in the other case. Other common toxicities were mild neutropenia, dehydration, hyperglycemia, and nausea/vomiting. One patient on dose level 1 showed a partial response of 6 months in duration. Both reversible inhibition of HDJ2 farnesylation and radiosensitization of a study patient-derived cell line were demonstrated in the presence of L-778,123. K-RAS mutations were found in three of the four patients evaluated. CONCLUSIONS: The combination of L-778,123 and radiotherapy at dose level 1 showed acceptable toxicity in patients with locally advanced pancreatic cancer. Radiosensitization of a patient-derived pancreatic cancer cell line was observed.  相似文献   
196.
We reviewed the results of percutaneous intervention of hilar biliary malignancy over a 10‐year period at a single institution: the Royal Melbourne Hospital. Ninety‐nine patients (100 treated in total) were included. Information was retrieved by retrospective examination of patient notes and radiology, combined with interviews with family and relevant physicians. Sixty‐nine patients were treated with insertion of semipermanent stents, 19 had external drain tubes, and 25 received percutaneous access for Iridium brachytherapy. Adequate drainage was achieved in 87% of the patients stented, and percutaneous access was successful in 96% of patients planned for brachytherapy. Of those patients undergoing endoprosthesis insertion, early complications occurred in 39% and late complications in 23%. Average survival for the entire patient population was 227.3 days, with a median of 167 days. Longer survival times (213 vs 142 days) and lower complication rates (44 vs 64%) are observed with metal stents in comparison with plastic stents. Percutaneous intervention is an important treatment option in hilar biliary malignancy, particularly in patients unfit for surgery. Reasonable survival with good palliation is the most common outcome, and most patients do not require further intervention.  相似文献   
197.
PURPOSE: To develop a genome-based classification scheme for clear-cell sarcoma (CCS), also known as melanoma of soft parts (MSP), which would have implications for diagnosis and treatment. This tumor displays characteristic features of soft tissue sarcoma (STS), including deep soft tissue primary location and a characteristic translocation, t(12;22)(q13;q12), involving EWS and ATF1 genes. CCS/MSP also has typical melanoma features, including immunoreactivity for S100 and HMB45, pigmentation, MITF-M expression, and a propensity for regional lymph node metastases. MATERIALS AND METHODS: RNA samples from 21 cell lines and 60 pathologically confirmed cases of STS, melanoma, and CCS/MSP were examined using the U95A GeneChip (Affymetrix, Santa Clara, CA). Hierarchical cluster analysis, principal component analysis, and support vector machine (SVM) analysis exploited genomic correlations within the data to classify CCS/MSP. RESULTS: Unsupervised analyses demonstrated a clear distinction between STS and melanoma and, furthermore, showed that CCS/MSP cluster with the melanomas as a distinct group. A supervised SVM learning approach further validated this finding and provided a user-independent approach to diagnosis. Genes of interest that discriminate CCS/MSP included those encoding melanocyte differentiation antigens, MITF, SOX10, ERBB3, and FGFR1. CONCLUSION: Gene expression profiles support the classification of CCS/MSP as a distinct genomic subtype of melanoma. Analysis of these gene profiles using the SVM may be an important diagnostic tool. Genomic analysis identified potential targets for the development of therapeutic strategies in the treatment of this disease.  相似文献   
198.
PURPOSE: Radiolabeled annexin V may allow for repetitive and selective in vivo identification of apoptotic cell death without the need for invasive biopsy. This study reports on the relationship between quantitative technetium-99m- (99mTc-) 6-hydrazinonicotinic (HYNIC) radiolabeled annexin V tumor uptake, and the number of tumor apoptotic cells derived from histologic analysis. PATIENTS AND METHODS: Twenty patients (18 men, two women) suspected of primary (n = 19) or recurrent (n = 1) head and neck carcinoma were included. All patients underwent a spiral computed tomography (CT) scan, 99mTc-HYNIC annexin V tomography, and subsequent surgical resection of the suspected primary or recurrent tumor. Quantitative 99mTc-HYNIC annexin V uptake in tumor lesions divided by the tumor volume, derived from CT, was related to the number of apoptotic cells per tumor high-power field derived from terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) assays performed on sectioned tumor slices. RESULTS: Diagnosis was primary head and neck tumor in 18 patients, lymph node involvement of a cancer of unknown primary origin in one patient, and the absence of recurrence in one patient. Mean percentage absolute tumor uptake of the injected dose per cubic centimeter tumor volume derived from tomographic images was 0.0003% (standard deviation [SD], 0.0004%) at 1 hour postinjection (PI) and 0.0001% (SD, 0.0000%) at 5 to 6 hours PI (P =.012). Quantitative 99mTc-HYNIC annexin V tumor uptake correlated well with the number of apoptotic cells if only tumor samples with no or minimal amounts of necrosis were considered. CONCLUSION: In the absence of necrosis, absolute 99mTc-HYNIC annexin V tumor uptake values correlate well with the number of apoptotic cells derived from TUNEL assays.  相似文献   
199.
PURPOSE: We sought to determine whether venous thromboembolism in cancer patients is associated with aberrant plasma levels of hemostatic and angiogenic factors. PATIENTS AND METHODS: Peripheral blood was collected before anticoagulant therapy from cancer patients with acute deep venous thrombosis (DVT; DVT + cancer group, n = 32), those without DVT (cancer control group, n = 36), and patients with acute DVT but no cancer (DVT control group, n = 58). Plasma assays of activation and inhibition of coagulation and fibrinolysis, as well as angiogenesis activation, were then performed. RESULTS: Median levels of thrombin-antithrombin complex, prothrombin fragments 1 + 2, and von Willebrand factor antigen were significantly greater in the DVT + cancer group than in the cancer control and DVT control groups (17.8 ng/mL v 4.6 ng/mL and 9.8 ng/mL, P =.0001 and P =.003, respectively; 3.65 nmol/L v 1.60 nmol/L and 2.71 nmol/L, P <.0001 and P =.011, respectively; and 4.04 U/mL v 2.26 U/mL and 2.06 U/mL, P <.0001, respectively). Median levels of tissue-type plasminogen activator were also significantly higher, while protein C activity was lower in the DVT + cancer group than in the DVT control group (14.6 ng/mL v 9.50 ng/mL, respectively, P =.0005; 0.89 U/mL v 1.11 U/mL, respectively, P =.0008). CONCLUSION: These data not only support prior observations of coagulation activation in patients with malignancy, but also provide new evidence for enhanced coagulation activation in the setting of acute venous thromboembolism in cancer. Future prospective studies are warranted to determine whether these and other potential markers of hypercoagulability may help to identify cancer patients at highest risk for venous thromboembolism.  相似文献   
200.
Basaloid squamous cell carcinoma (BSCC) is a rare form of cancer that arises primarily in the upper aerodigestive tract. Esophageal BSCC is extremely rare, accounting for less than 2% of primary esophageal malignancies. It is histopathologically distinct from squamous cell carcinoma and has an aggressive biological behavior with poor survival outcomes. There is no known association of Barrett’s esophagus with esophageal BSCC. Here, we report what we believe is the first such case of esophageal BSCC occurring in the setting of Barrett’s esophagus.  相似文献   
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