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11.
The management of rheumatoid arthritis (RA) with biological response modifiers (BRMs) is reviewed. RA, an autoimmune disorder affecting 1-2% of the world's population, is characterized by inflammation of synovial tissues, joint swelling, stiffness, and pain that may progress to joint erosion. There is strong evidence that inflammatory mediators, such as tissue necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1), play a critical role in the pathogenesis of this disorder. IL-1-receptor antagonist (IL-1Ra) is produced in healthy subjects and helps to protect against the adverse effects associated with IL-1 overexpression. Administration of IL-1Ra or similar agents may reduce the effects of IL-1 and ameliorate inflammatory conditions. Traditional treatment of RA has been based on symptomatic management with non-steroidal antiinflammatory drugs, disease-modifying antirheumatic drugs, and corticosteroids, each of which has substantial drawbacks in terms of effectiveness or adverse effects. Newer therapeutic strategies for blocking the biological effects of inflammatory cytokines include antibodies directed against TNF (e.g., infliximab), soluble receptors (e.g., etanercept) and receptor antagonists to IL-1 (anakinra) [corrected]. Clinical trials indicate that these BRMs may be more effective than traditional agents because they are able to alter joint remodeling in addition to attenuating symptoms. Anti-TNF therapies may be associated with increased risk for infections, sepsis, tuberculosis reactivation, demyelination disorders, and blood dyscrasias; anakinra appears to be safer. Combination therapy with BRMs may be more appropriate for RA than monotherapy. The role of BRMs in the treatment of RA will evolve as investigators learn more about the drugs and the disorder. 相似文献
12.
Antoinette R Tan Xiaowei Yang Stephen M Hewitt Arlene Berman Erin R Lepper Alex Sparreboom Allyson L Parr William D Figg Catherine Chow Seth M Steinberg Stephen L Bacharach Millie Whatley Jorge A Carrasquillo Jaime S Brahim Seth A Ettenberg Stan Lipkowitz Sandra M Swain 《Journal of clinical oncology》2004,22(15):3080-3090
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
13.
OBJECTIVE AND IMPORTANCE: Vestibular schwannomas with meningioma islets have been rarely reported in the literature; they have been observed only among patients with neurofibromatosis Type II. We present a case of a sporadic mixed tumor in a patient without neurofibromatosis Type II that was not suspected before surgery. CLINICAL PRESENTATION: A 59-year-old female patient presented with clinical signs of progressive loss of hearing. Her family history did not include evidence of neurological diseases. Magnetic resonance imaging scans revealed a typical unilateral vestibular schwannoma. INTERVENTION: The tumor presented with invasion of the surrounding arachnoid membrane, as well as Cranial Nerves VII and VIII. Preservation of the facial nerve with complete removal of the tumor was not possible. Therefore, Cranial Nerve VII reconstruction was performed. CONCLUSION: The concomitant occurrence of schwannomas and meningiomas infiltrating the arachnoid membrane might be related to poor clinical outcomes for patients with neurofibromatosis Type II, with respect to preservation of facial and acoustic nerves. Among sporadic schwannomas, this phenomenon is extremely rare. 相似文献
14.
Steinar Aamdal Uta Bruntsch Jean Kerger Jaap Verweij Wim Bokkel Huinink Jantien Wanders Ram Rastogi Hillary R. Franklin Stan B. Kaye 《Cancer chemotherapy and pharmacology》1997,40(5):439-443
The antitumor activity of zeniplatin, a third-generation, water-soluble platinum compound that has shown broad preclinical
antitumor activity and no significant nephrotoxicity in phase I trials, was tested in patients with advanced malignant melanoma
and advanced renal cancer. Patients who had not previously been treated, except with local limb perfusion and immunotherapy,
were given zeniplatin as bolus injections at 125 mg/m2 every 3 weeks. The main hematological toxicity was leukopenia (7/30 patients, WHO grade ≥ 3) and the main nonhematological
toxicity was nausea and vomiting (21/30 patients, WHO grade ≥ 2). Serious nephrotoxicity was observed early in the renal cancer
study and, later, also in the melanoma study. Hyperhydration did not prevent the nephrotoxicity, and the studies were stopped
after 6 renal cancer patients and 24 malignant melanoma patients had been included. Zeniplatin gave objective responses in
3 of the 21 evaluable malignant melanoma patients [2 complete responses (CRs) in patients with lymph-node metastases lasted
5 and 14 months, respectively; 1 partial response (PR) in a patient with lymph-node and liver metastases lasted 6 months].
In the renal cancer study, only four patients were evaluable for response and none responded. The results show that zeniplatin
has some activity (14%) in patients with advanced malignant melanoma, but no conclusion can be drawn regarding the activity
of zeniplatin in renal cancer as the number of patients was too low. The main toxicities were leukopenia and nausea and vomiting.
Unexpected and serious nephrotoxicity was observed, and for this reason the studies were terminated before the planned number
of patients had been included. A possible explanation for the nephrotoxicity may be drug interactions, but no firm conclusion
can yet be drawn.
Received: 16 March 1996 / Accepted: 25 March 1997 相似文献
15.
Disruption of intracerebral progression of C6 rat glioblastoma by in vivo treatment with anti-CD44 monoclonal antibody 总被引:3,自引:0,他引:3
Breyer R Hussein S Radu DL Pütz KM Gunia S Hecker H Samii M Walter GF Stan AC 《Journal of neurosurgery》2000,92(1):140-149
OBJECT: Glioblastoma multiforme (GBM) invasiveness is a complex process that involves recognition and attachment of GBM cells to particular extracellular matrix (ECM) molecules before migrating into proteolytically modified matrix and inducing angiogenesis. The CD44 molecule, which is a transmembrane adhesion molecule found on a wide variety of cells including GBM, has been suggested as the principal mediator of migration and invasion. The aim of the present study was to demonstrate whether an antibody specific to the standard form of CD44 (CD44s, 85-90 kD) might prevent invasion and thus disrupt progression of C6 GBM in vivo. METHODS: Immunostaining demonstrated homogeneous expression of CD44s on the surface of C6 GBM cells and tumors. Flow cytometric analysis demonstrated binding saturation of anti-CD44s monoclonal antibody (mAb) to the receptor at 1 microg/5 x 10(5) cells. Blocking of CD44s in vitro resulted in a dose-dependent progressive (up to 94+/-2.7%; mean +/- standard deviation [SD]) detachment of C6 cells from ECM-coated culture. Blocking of CD44s in vivo resulted in significantly reduced C6 brain tumors (3.6+/-0.4% [SD])--measured as the quotient: tumor surface (mm2)/brain surface (mm2) x 100--compared with untreated (19.9+/-0.9%) or sham-treated (19.2+/-1.1 to 19.3+/-2.5% [SD]) rats. Disruption of C6 GBM progression correlated with an improved food intake; treated rats were significantly less cachectic (166.6+/-16.4 g [SD]) than those that were untreated (83+/-2.7 g [SD]) or sham-treated (83.4+/-1.1 to 83+/-2.2 g [SD]) rats. CONCLUSIONS: The authors conclude that CD44s-targeted treatment with specific mAb may represent an effective means for preventing progression of highly invasive GBMs. 相似文献
16.
17.
Graham G Dark A Hilary Calvert Robert Grimshaw Christopher Poole Ken Swenerton Stan Kaye Robert Coleman Gordon Jayson Tien Le Susan Ellard Marc Trudeau Paul Vasey Marta Hamilton Terri Cameron Emma Barrett Wendy Walsh Lynn McIntosh Elizabeth A Eisenhauer 《Journal of clinical oncology》2005,23(9):1859-1866
PURPOSE: Liposomal lurtotecan (OSI-211) is a liposomal formulation of the water-soluble topoisomerase I inhibitor lurtotecan (GI147211), which demonstrated superior levels of activity compared with topotecan in preclinical models. We studied two schedules of OSI-211 in a randomized design in relapsed ovarian cancer to identify the more promising of the two schedules for further study. PATIENTS AND METHODS: Eligible patients had measurable epithelial ovarian, fallopian, or primary peritoneal cancer that was recurrent after one or two prior regimens of chemotherapy. Patients were randomly assigned to receive either arm A (OSI-211 1.8 mg/m(2)/d administered by 30-minute intravenous infusion on days 1, 2, and 3 every 3 weeks) or arm B (OSI-211 2.4 mg/m(2)/d administered by 30-minute intravenous infusion on days 1 and 8 every 3 weeks). The primary outcome measure was objective response, which was confirmed by independent radiologic review, and a pick the winner statistical design was used to identify the schedule most likely to be superior. RESULTS: Eighty-one patients were randomized between October 2000 and September 2001. The hematologic toxic effects were greater on arm A than on arm B (grade 4 neutropenia, 51% v 22%, respectively), as was febrile neutropenia (26% v 2.4%, respectively). Of the 80 eligible patients, eight patients (10%) had objective responses; six responders (15.4%; 95% CI, 6% to 30%) were in arm A and two responders (4.9%; 95% CI, 1% to 17%) were in arm B. CONCLUSION: The OSI-211 daily for 3 days intravenous schedule met the statistical criteria to be declared the winner in terms of objective response. This schedule was also associated with more myelosuppression than the schedule of OSI-211 administered in arm B. 相似文献
18.
Human papillomavirus infection and cervical disease in human immunodeficiency virus-1-infected women
Denny L Boa R Williamson AL Allan B Hardie D Stan R Myer L 《Obstetrics and gynecology》2008,111(6):1380-1387
OBJECTIVE: To report on the natural history of high-risk human papillomavirus (HPV) infection and cervical disease in human immunodeficiency virus (HIV)-1-infected women living in Cape Town, South Africa. METHODS: This was a prospective study of 400 untreated, HIV-1-infected women who underwent high-risk HPV DNA testing, cytology, colposcopy, histology, and CD4 count testing every 6 months for 36 months. Human immunodeficiency virus viral loads and HPV type distribution were determined at entry and after 18 months. RESULTS: Sixty-eight percent of the women were high-risk HPV DNA positive at entry, 35% had a cytologic diagnosis of low-grade squamous intraepithelial lesion (LSIL), and 13% had high-grade squamous intraepithelial lesion (HSIL). There were no cancers. Abnormal cytology and high-risk HPV positivity were strongly correlated with low CD4 counts and high HIV viral loads. The most prevalent types of HPV were HPV-16, -52, -53, -35, and -18. Incident high-risk HPV infection occurred in 22%, and of those infected with high-risk HPV, 94% of infections persisted over an 18-month period, and 6% cleared their infections. Cytologic progression to SIL from normal/atypical squamous cells of undetermined significance cytology occurred in 17% of cases, but only 4% of cases of LSIL progressed to HSIL. CONCLUSION: There is a high level of high-risk HPV infection in HIV-1 infected women, but progression to HSIL over 36 months occurred in the minority of cases. We recommend an initial colposcopy for an abnormal test, and if no high-grade lesion is identified, triennial screening would be appropriate. Human papillomavirus type 16 was the commonest, and HPV-18 was the fifth commonest, suggesting that vaccination against these two types would have a significant effect. LEVEL OF EVIDENCE: II. 相似文献
19.
Unmet need for contraception represents a major failure in the provision of reproductive health services and reflects the extent of access to services for spacing and limiting births, which are also affected by personal, partner, community and health system factors. In the context of the Millennium Development Goals, family planning has been given insufficient attention compared to maternal health and the control of sexually transmitted infections. As this omission is being redressed, efforts should be directed towards ensuring that an indicator of unmet need is used as a measure of access to services. The availability of data on unmet need must also be increased to enable national comparisons and facilitate resource mobilisation. Unmet need is a vital component in monitoring the proportion of women able to space and limit births. Unmet need for contraception is a measure conditioned by people's preferences and choices and therefore firmly introduces a rights perspective into development discourse and serves as an important instrument to improve the sensitivity of policy dialogue. The new reproductive health target and the opportunity it offers to give appropriate attention to unmet need for contraception will allow the entry of other considerations vital to ensuring universal access to reproductive health. 相似文献
20.
Marius Sebastian Secula Igor Cretescu Benoit Cagnon Liliana Rozemarie Manea Corneliu Sergiu Stan Iuliana Gabriela Breaban 《Materials》2013,6(7):2723-2746
The aim of this study was to determine the effects of main factors and interactions on the color removal performance from dye solutions using the electrocoagulation process enhanced by adsorption on Granular Activated Carbon (GAC). In this study, a mathematical approach was conducted using a two-level fractional factorial design (FFD) for a given dye solution. Three textile dyes: Acid Blue 74, Basic Red 1, and Reactive Black 5 were used. Experimental factors used and their respective levels were: current density (2.73 or 27.32 A/m2), initial pH of aqueous dye solution (3 or 9), electrocoagulation time (20 or 180 min), GAC dose (0.1 or 0.5 g/L), support electrolyte (2 or 50 mM), initial dye concentration (0.05 or 0.25 g/L) and current type (Direct Current—DC or Alternative Pulsed Current—APC). GAC-enhanced electrocoagulation performance was analyzed statistically in terms of removal efficiency, electrical energy, and electrode material consumptions, using modeling polynomial equations. The statistical significance of GAC dose level on the performance of GAC enhanced electrocoagulation and the experimental conditions that favor the process operation of electrocoagulation in APC regime were determined. The local optimal experimental conditions were established using a multi-objective desirability function method. 相似文献