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31.
PURPOSE: To determine the antitumor activity of ABX-EGF, a fully human monoclonal antibody to the epidermal growth factor receptor (EGFr), in previously treated patients with metastatic renal cell carcinoma, and to characterize its toxicity, immunogenicity, pharmacokinetics, and pharmacodynamics. PATIENTS AND METHODS: The antitumor activity, as well as the toxicity, pharmacokinetics, pharmacodynamics, and immunogenicity of ABX-EGF, were assessed. RESULTS: Eighty-eight patients were treated with ABX-EGF doses of 1.0, 1.5, 2.0, or 2.5 mg/kg weekly with no loading dose. EGFr immunostaining was performed on 76 tumor biopsy specimens (86%), and 69 (91%) scored positive. Major responses occurred in three patients, and two patients had minor responses. Forty-four patients (50%) also had stable disease at their first 8-week assessment, and the median progression-free survival (PFS) was 100 days (95% CI, 58 to 140 days). Low hemoglobin and high alkaline phosphatase predicted for short PFS. The principal toxicity, an acneiform rash, occurred in 68%, 95%, 87%, and 100% of patients who received at least three doses of ABX-EGF at 1.0, 1.5, 2.0, and 2.5 mg/kg/wk, respectively. A trend indicated that the severity of the rash may relate to PFS. No human antihuman antibodies were detected. ABX-EGF pharmacokinetics fit a model that incorporated both linear and saturable EGFr-mediated clearance mechanisms, and interindividual variability was low. At 2.5 mg/kg/wk, ABX-EGF concentrations throughout treatment exceeded those estimated to saturate nonlinear clearance and inhibit xenograft growth by 90%. CONCLUSION: ABX-EGF was generally well tolerated. The objective response rate was low in previously treated patients with metastatic renal cell carcinoma. Although skin rash may be a pharmacodynamic marker of drug action, its potential as a surrogate marker of clinical benefit requires further evaluation.  相似文献   
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Higher fat and energy intakes confer a survival advantage in cystic fibrosis (CF). There is a need to develop effective nutrition programmes that ensure optimal energy intake in CF.

Methodology:


A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.

Results:


Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.

Conclusion:


Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item.  相似文献   
33.
Intestinal permeability can be assessed non-invasively using the lactulose-rhamnose (L-R) test, which is a reliable measure of small intestinal integrity. AIMS: To determine risk factors for abnormal intestinal permeability in kwashiorkor, and to measure changes in L-R ratios with inpatient rehabilitation. DESIGN: A case-control study of 149 kwashiorkor cases and 45 hospital controls. The L-R test was adapted to study kwashiorkor in Malawi, with testing at weekly intervals during nutritional rehabilitation. Urine sugars were measured by thin layer chromatography in London. RESULTS: The initial geometric mean L-R ratios (x100) (with 95% confidence interval) in kwashiorkor were 17.3 (15.0 to 19.8) compared with 7.0 (5.6 to 8.7) for controls. Normal ratios are < 5, so the high ratios in controls indicate tropical enteropathy syndrome. Abnormal permeability in kwashiorkor was associated with death, oliguria, sepsis, diarrhoea, wasting and young age. Diarrhoea and death were associated with both decreased L-rhamnose absorption (diminished absorptive surface area) and increased lactulose permeation (impaired barrier function) whereas nutritional wasting affected only L-rhamnose absorption. Despite, clinical recovery, mean L-R ratios improved little on treatment, with mean weekly ratios of 16.3 (14.0 to 19.0), 13.3 (11.1 to 15.9) and 14.4 (11.0 to 18.8). CONCLUSION: Abnormal intestinal permeability in kwashiorkor correlates with disease severity, and improves only slowly with nutritional rehabilitation.  相似文献   
34.
OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease.  相似文献   
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In this study we have analyzed the vascular response induced in the two- stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not been explored in this model, which is the paradigm of multistage carcinogenesis and a model for neoplastic lesions derived from exophytic premalignant lesions (e.g. colon carcinoma, bladder papilloma). We investigated if angiogenesis is involved in the formation of papillomas and in the progression from papilloma to carcinoma. To this end we analyzed the vasculature of normal and hyperplastic skin, focal epidermal hyperplasias that are precursors of papillomas, papillomas at different stages and squamous cell carcinomas. We also analyzed the vascularization of papillomas induced in two strains of mice that differ in their susceptibility to malignant progression. We show here that angiogenesis is turned on in the earliest stages of papilloma formation. In late stages, regardless of state of progression, the predominant response is an increase in the size of blood vessels. Thus, in the SENCAR mouse model, representative of exophytic tumors, the angiogenesis switch is a very early event, probably mechanistically related to the development of the primarily exophytic lesions. Therefore, the density of blood vessels cannot be used as a predictor of malignant progression in this model.   相似文献   
38.
BACKGROUND: A phase III trial in patients with malignant pleural mesothelioma demonstrated a survival advantage for pemetrexed plus cisplatin compared with single-agent cisplatin. Because post-study chemotherapy (PSC) may have influenced the outcome of the trial, we examined its use and association with survival. PATIENTS AND METHODS: Eighty-four patients from the pemetrexed plus cisplatin arm and 105 patients from the single-agent cisplatin arm received PSC. Kaplan-Meier survival estimates were compared by treatment groups, and by PSC and non-PSC subgroups. RESULTS: The percentage of patients receiving PSC was imbalanced between the treatment arms. Fewer pemetrexed plus cisplatin treated patients received PSC (37.2% versus 47.3%). A multiple regression analysis performed in this trial showed that PSC had a statistically significant correlation with prolonged survival (P <0.01), adjusting for baseline prognostic factors and treatment intervention. The adjusted hazard ratio for PSC over non-PSC subgroups was 0.56 (confidence interval 0.44-0.72). CONCLUSIONS: PSC in malignant pleural mesothelioma was significantly associated with prolonged survival. It is not known whether the reduced risk of death was associated with PSC or whether patients who had prolonged survival tended to receive more PSC. The pemetrexed plus cisplatin treatment group had a statistically significant survival advantage even though fewer patients from that arm of the trial received PSC. The potentially beneficial role of PSC should be assessed in prospective trials.  相似文献   
39.
ObjectivesThis study aims to provide insight into (i) how the combination of paid work and family care is longitudinally associated with gender-related differences in depressive symptoms and (ii) the role of work characteristics in this association.MethodsData were derived from STREAM, a Dutch prospective cohort study of older workers aged 45–64 years. Respondents were included if they were employed in at least one measurement between 2015 and 2017 (N=12 447). Mixed-models were applied to disentangle between-person (BP) and within-person (WP) effects of family caregiving on depressive symptoms. Analyses were stratified by gender. Work characteristics (social support, autonomy, emotional and mental workload) were separately added to the multivariable models.ResultsFor older employees, family caregiving was positively associated with depressive symptoms between and within persons for both women [BP B=0.80, 95% confidence interval (CI) 0.52–1.08; WP B=0.32, 95% CI 0.08–0.56] and men (BP B=0.75, 95% CI 0.45–1.05; WP B=0.25, 95% CI 0.01–0.48). Social support at work reduced the adverse effect of family care on depressive symptoms for women (BP) and men (BP and WP). Emotional workload partly explained the effect of family care for both women and men (BP).ConclusionsThe longitudinal association between family care and mental health was similar for male and female employees. Resources at work (ie, social support) could protect caregiving employees against depressive symptoms. More research is needed regarding the relative impact of the care context compared to the work context of working family caregivers.  相似文献   
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