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81.
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The objective of this phase II and pharmacologic study was to explore the feasibility, toxicity and activity of adaptive intrapatient dose escalation of cisplatin in a dose-intensive weekly schedule using predefined levels of exposure, with the ultimate aim to improve the antitumour activity of the therapy in patients with nonsmall cell lung cancer (NSCLC). Platinum DNA-adduct levels in peripheral white blood cells during treatment were used as the primary parameter for adaptive dosing. If DNA-adduct levels were not available, the area under the concentration-time curve (AUC) of unbound platinum in plasma was used for dose adaptation. Target levels for DNA-adducts and AUC have been defined in a previously performed pharmacologic study. The feasibility of adaptive dosing was tested in 76 patients with stage IIIB and IV NSCLC, who were planned to receive 6 weekly courses of cisplatin at a starting dose of 70 mg m(-2), together with daily low oral dose of 50 mg VP16. In total, 37 patients (49%) who were given more than one course received a dose increase varying from 10 to 55%. The majority of patients reached the defined target levels by a dose increase during course two. Relevant grade 2 neurotoxicity was observed in eight (10%) patients and reversible ototoxicity grade 2 in 14 (18%) patients. The strategy of adaptive intrapatient dose adjustment of cisplatin is practically feasible in a research setting even when results for dose adaptation have to be reported within a short time-period of 1 week. The toxicity appeared to be manageable in this cohort of patients. In some patients, exposure after the standard dose was substantially lower than the defined target level and significant dose escalations of more than 50% had to be applied. The response rate (RR) was relatively high: overall 40% (29 out of 72 patients) partial remission (PR), in patients with stage IIIB the RR was 60% (15 out of 25 patients) and with stage IV 30% (14 out of 47 patients). Randomised studies are needed to determine whether the adaptive dosing strategy results in better efficacy than standard dosing.  相似文献   
84.
Zagrodnik B  Kempf W  Seifert B  Müller B  Burg G  Urosevic M  Dummer R 《Cancer》2003,98(12):2708-2714
BACKGROUND: The histologic subtype of a basal cell carcinoma (BCC) may be an important factor for the success of a certain treatment modality. In the current article, the authors report recurrence rates among patients with BCC after superficial radiotherapy as well as Bcl-2 and p53 expression levels stratified by BCC subtype. METHODS: The authors performed a retrospective study of 175 BCCs in 148 patients (64 female patients and 84 male patients; mean age, 69 years) who were treated with radiotherapy. According to their histologic patterns, BCCs were classified as nodular (n = 103), superficial (n = 25), and sclerosing (n = 47). In addition, six patients with metatypic BCC were reviewed. Bcl-2 and p53 protein expression was examined on a tissue microarray of 60 BCC samples (18 nodular tumors, 12 superficial tumors, and 30 sclerosing tumors). RESULTS: The estimated 5-year recurrence rate for all patients with BCC was 15.8%: 8.2% for patients with the nodular subtype, 26.1% for patients with the superficial subtype, and 27.7% for patients with the sclerosing subtype (Kaplan-Meier analysis: P = 0.055). The median follow-up was 48 months. The mean time to recurrence was 20 months, and 86.4% of all recurrences occurred within 3 years after treatment. No gender-specific differences were observed. In addition, one of six metatypic BCCs recurred. Nuclear p53 immunoreactivity and low Bcl-2 expression were significantly correlated with the sclerosing subtype. Overall, 61.5% of patients developed additional neoplasms during follow-up (76 developed additional BCCs, 15 developed squamous cell carcinomas, and 6 developed Bowen disease). CONCLUSIONS: The sclerosing subtype of BCC was a risk factor for recurrence after radiotherapy. In contrast, excellent results were achieved for patients with predominant nodular subtype. Nevertheless, radiotherapy may be the therapy of choice for patients with all BCC subtypes, depending on the individual patient's characteristics. Expression analyses confirmed that p53 and Bcl-2 levels may be used as indicators for the aggressiveness of a BCC subtype. Due to the high incidence of additional skin malignancies, patients with BCC need careful follow-up.  相似文献   
85.
Northern blotting confirmed previous results indicating that the mitogen-activated protein kinase (MAPK) phosphatase Pyst2-L was highly expressed in leukocytes obtained from acute myeloid leukemia (AML) patients. High levels of Pyst2-L mRNA were expressed in bone marrow (BM) and peripheral leukocytes from nine AML and acute lymphoblastic leukemia (ALL) patients. BM from healthy individuals expressed very low levels of Pyst2-L. Whereas high levels of Pyst2-L mRNA and protein were detected in several leukemia cell lines, Pyst2-L mRNA was detected neither in 33/34 samples of normal peripheral blood mononuclear cells (PBMC) nor in leukocyte fractions enriched with CD34+ cells. Certain solid tumor and lymphoblastoid cell lines expressed high levels of Pyst2-L mRNA. In view of the association of Pyst2-L to MAPK signaling cascades, we tested if cell activation, a process involving MAPK signaling, influences Pyst2-L expression. Indeed, activation of T cells and endothelial cells increased Pyst2-L in these cells. Furthermore, TPA, a known MAPK activator, induces the expression of both Pyst2-L mRNA as well as the Pyst2-L protein in leukemia cells. This induction was partially inhibited by PD098059, an Mek1/2-specific inhibitor. Based on the results of this and previous studies, we hypothesize that the high levels of Pyst2-L detected in the active state of AML and ALL diseases and in other types of cancer reflect an altered MAPK signaling pathway in such malignant processes. This alteration may be the result of a failed attempt to counter the constitutive activation of MAPK in transformed cells or alternatively, may represent the activated state of such cells.  相似文献   
86.
Depression is an important predictor of morbidity and mortality in patients with coronary disease, particularly after myocardial infarction, independent of previous cardiac history or CAD severity. Depression also is associated with poor long-term psychosocial outcomes. The prevalence of major depression among post-MI patients is 15 to 20%, with an additional 27% reporting symptoms of minor depression. This article briefly reviews the literature on depression in patients with coronary disease, including previously published efforts to treat the disorder in this group. A case review then is provided, highlighting important aspects of treatment.  相似文献   
87.
The neutrophil: function and regulation in innate and humoral immunity   总被引:8,自引:0,他引:8  
The neutrophil is a critical effector cell in humoral and innate immunity and plays vital roles in phagocytosis and bacterial killing. Discussed here are the neutrophil components necessary for these processes and the diseases in which these components are either lacking or dysfunctional, illustrating that normal neutrophil function is vital for health.  相似文献   
88.
Context  Depression and low perceived social support (LPSS) after myocardial infarction (MI) are associated with higher morbidity and mortality, but little is known about whether this excess risk can be reduced through treatment. Objective  To determine whether mortality and recurrent infarction are reduced by treatment of depression and LPSS with cognitive behavior therapy (CBT), supplemented with a selective serotonin reuptake inhibitor (SSRI) antidepressant when indicated, in patients enrolled within 28 days after MI. Design, Setting, and Patients  Randomized clinical trial conducted from October 1996 to April 2001 in 2481 MI patients (1084 women, 1397 men) enrolled from 8 clinical centers. Major or minor depression was diagnosed by modified Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria and severity by the 17-item Hamilton Rating Scale for Depression (HRSD); LPSS was determined by the Enhancing Recovery in Coronary Heart Disease Patients (ENRICHD) Social Support Instrument (ESSI). Random allocation was to usual medical care or CBT-based psychosocial intervention. Intervention  Cognitive behavior therapy was initiated at a median of 17 days after the index MI for a median of 11 individual sessions throughout 6 months, plus group therapy when feasible, with SSRIs for patients scoring higher than 24 on the HRSD or having a less than 50% reduction in Beck Depression Inventory scores after 5 weeks. Main Outcome Measures  Composite primary end point of death or recurrent MI; secondary outcomes included change in HRSD (for depression) or ESSI scores (for LPSS) at 6 months. Results  Improvement in psychosocial outcomes at 6 months favored treatment: mean (SD) change in HRSD score, -10.1 (7.8) in the depression and psychosocial intervention group vs -8.4 (7.7) in the depression and usual care group (P<.001); mean (SD) change in ESSI score, 5.1 (5.9) in the LPSS and psychosocial intervention group vs 3.4 (6.0) in the LPSS and usual care group (P<.001). After an average follow-up of 29 months, there was no significant difference in event-free survival between usual care (75.9%) and psychosocial intervention (75.8%). There were also no differences in survival between the psychosocial intervention and usual care arms in any of the 3 psychosocial risk groups (depression, LPSS, and depression and LPSS patients). Conclusions  The intervention did not increase event-free survival. The intervention improved depression and social isolation, although the relative improvement in the psychosocial intervention group compared with the usual care group was less than expected due to substantial improvement in usual care patients.   相似文献   
89.
Tumor-specific T-helper (Th) immunity was found to play a pivotal role in the natural and vaccine-induced immune defense against tumors. Since the majority of cervical cancers express human papillomavirus type 16 (HPV16) E7 oncoprotein, it is important to investigate the Th response against this target antigen in detail. By means of PBMC cultures from HLA-typed healthy donors, we identified the central part of HPV16 E7 (E7(41-72)) as the major immunogenic region within this antigen. Furthermore, we mapped 3 distinct Th epitopes within this region (DR15/E7(50-62), DR3/E7(43-77), DQ2/E7(35-50)). In a parallel approach, employing IFN-gamma ELISPOT analysis, we detected Th immunity against HPV16 E7 in subjects with HPV16+ lesions. Several of these responses matched with the 3 Th epitopes defined in our study. A number of other HPV16+ subjects did not display any E7-specific type 1 cytokine-producing T-cell immunity, indicating failure of the immune response. Our combined data argue for more extensive as well as longitudinal analysis of HPV16-specific T-cell immunity using the ELISPOT assay described, as well as for HPV-specific vaccination of individuals with HPV+ lesions.  相似文献   
90.
We describe a case of cicatricial pemphigoid in a 92-year-old female with extensive mucocutaneous involvement. She developed extensive hemorrhagic blistering with severely bleeding lesions, that healed with scarring. The conjunctivae showed extensive synechia. The diagnosis was based on clinical and histopathological features as well as immunofluorescence findings and immunoblot analysis. There was no clinical response to topical corticosteroids. The patient was given tetracycline and nicotinamid and showed rapid improvement of the mucocutaneous lesions within a few weeks. The clinical features, differential diagnosis and various treatment modalities of cicatricial pemphigoid are briefly reviewed, whereby the use of tetracycline and nicotinamide is discussed as an alternative effective and safe therapy for this potentially incapacitating condition.  相似文献   
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