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R Knight

Publications and source records attributed to R Knight.

At least 19 recordsLinked to original sources

Lenalidomide and pegylated liposomal doxorubicin-based chemotherapy for relapsed or refractory multiple myeloma: safety and efficacy.

BACKGROUND: Lenalidomide is active and well tolerated in relapsed and refractory multiple myeloma. We conducted a phase I/II trial of the combination of lenalidomide and chemotherapy to evaluate the safety and efficacy of the combination. METHODS: The 62 patients enrolled received liposomal doxorubicin 40 mg/m(2) i.v. and vincristine 2 mg i.v. on day 1, dexamethasone 40 mg p.o. on days 1-4 (DVd), and lenalidomide on days 1-21 in 28-day cycles. Primary end points were maximum tolerated dose (MTD) of lenalidomide with DVd chemotherapy and overall response rate (ORR) by Southwest Oncology Group criteria of the combination. FINDINGS: The median age was 62 years, 70% of patients were males and 65% had refractory multiple myeloma. The MTD of lenalidomide with DVd chemotherapy was 10 mg and the dose-limiting toxicity was non-neutropenic sepsis. After 7.5 months of median follow-up, the ORR of the combination was 75%, with 29% of patients achieving a complete or near complete remission. The median progression-free survival was 12 months, while the median overall survival has not yet been reached. INTERPRETATION: The combination of lenalidomide and DVd chemotherapy was well tolerated and resulted in high response rates in this mostly refractory patient population. Evaluation of this combination in newly diagnosed patients is warranted.

Aged↗

CSF tests in the differential diagnosis of Creutzfeldt-Jakob disease.

OBJECTIVES: To analyze the diagnostic sensitivity and specificity of various brain-derived proteins (14-3-3, Tau, neuron specific enolase [NSE], and S100b) in the CSF of patients with Creutzfeldt-Jakob disease (CJD) and to analyze biologic factors that modify these parameters. METHODS: CSF was tested for 14-3-3, Tau, NSE, and S100b in 1,859 patients with sporadic, genetic, iatrogenic, and variant CJD, and in 1,117 controls. RESULTS: The highest sensitivity was achieved for 14-3-3 and Tau in sporadic CJD (85% and 86%), and a combined determination of 14-3-3 and Tau, S100b, or NSE increased the sensitivity to over 93%. A multivariate analysis showed that the sensitivity of all tests was highest in patients with the shortest disease duration, age at onset >40 years, and homozygosity at codon 129 of the prion protein gene. In a group of patients with repeated lumbar punctures, a second test also increased the diagnostic sensitivity. CONCLUSIONS: The detection of elevated levels of brain-derived proteins in the CSF in patients with suspected Creutzfeldt-Jakob disease is a valuable diagnostic test. A second lumbar puncture may be of value in patients with atypical clinical course in whom the first test was negative.

14-3-3 Proteins↗

Phase I study of the thrombospondin-1-mimetic angiogenesis inhibitor ABT-510 with 5-fluorouracil and leucovorin: a safe combination.

We performed a phase I study with the thrombospondin-1-mimetic angiogenesis inhibitor ABT-510 combined with 5-fluorouracil and leucovorin (5-FU/LV) to determine safety profile and assess pharmacokinetic interactions. Patients with advanced solid malignancies received LV 20 mg/m(2) followed by 5-FU 425 mg/m(2) both administered intravenously in 15 min daily for 5 days every 4 weeks. ABT-510 was administered subcutaneously twice daily continuously from day 2 onwards. Blood and urine samples for pharmacokinetic analyses were collected at days 1, 5 and 22. Twelve patients received a total of 45 cycles of 5-FU/LV combined with ABT-510. ABT-510 dose levels studied were 50 and 100 mg. The combination was well tolerated, with a toxicity profile comparable to that of 5-FU/LV alone. At the dose levels studied no significant pharmacokinetic interactions were observed. These data indicate that ABT-510 administered twice daily subcutaneously can be safely combined with 5-FU/LV administered daily for 5 days, every 4 weeks.

Aged↗

Evaluation of urinary PrPSc as a diagnostic test for sporadic, variant, and familial CJD.

Previously collected urine specimens from 100 patients referred to the UK National CJD Surveillance Unit as suspected cases of Creutzfeldt-Jakob disease (CJD) were analyzed, testing for abnormal prion protein (PrP(Sc)). In this context, the test had a low sensitivity and was not completely specific for CJD. Additionally, the proteins detected by this assay were not PrP(Sc) but appeared to be immunoglobulins.

Antibody Specificity↗

Mortality from Creutzfeldt-Jakob disease and related disorders in Europe, Australia, and Canada.

BACKGROUND: An international study of the epidemiologic characteristics of Creutzfeldt-Jakob disease (CJD) was established in 1993 and included national registries in France, Germany, Italy, the Netherlands, Slovakia, and the United Kingdom. In 1997, the study was extended to Australia, Austria, Canada, Spain, and Switzerland. METHODS: Data were pooled from all participating countries for the years 1993 to 2002 and included deaths from definite or probable CJD of all etiologic subtypes. RESULTS: Four thousand four hundred forty-one cases were available for analysis and included 3,720 cases of sporadic CJD, 455 genetic cases, 138 iatrogenic cases, and 128 variant cases. The overall annual mortality rate between 1999 and 2002 was 1.67 per million for all cases and 1.39 per million for sporadic CJD. Mortality rates were similar in all countries. There was heterogeneity in the distribution of cases by etiologic subtype with an excess of genetic cases in Italy and Slovakia, of iatrogenic cases in France and the UK, and of variant CJD in the UK. CONCLUSIONS: This study has established overall epidemiologic characteristics for Creutzfeldt-Jakob disease (CJD) of all types in a multinational population-based study. Intercountry comparisons did not suggest any relative change in the characteristics of sporadic CJD in the United Kingdom, and the evidence in this study does not suggest the occurrence of a novel form of human bovine spongiform encephalopathy infection other than variant CJD. However, this remains a possibility, and countries currently unaffected by variant CJD may yet have cases.

Adolescent↗

Rabbit antithymocyte globulin: a postoperative risk factor for sirolimus-treated renal transplant patients?

AIMS: Randomized controlled studies suggest an increased incidence of perioperative wound complications among sirolimus-treated renal transplant patients. The present study analyzed the effect of rabbit antithymocyte globulin (rATG) on these postoperative complications. METHODS: Four hundred and twelve renal transplants were performed and managed postoperatively at two University-affiliated hospitals between January 1, 2001, and December 31, 2003. The patients received corticosteroids and Sirolimus, with delayed introduction of cyclosporine when the serum creatinine had decreased below 2.5 mg/dL. Two groups of patients were discriminated: group 1 received Basiliximab 20 mg on day 0 and day 4 (n = 283); group 2 recipients with a high panel of reactive antibody (PRA > 20%) and retransplant patients received rATG for induction (n = 129) for a maximum of 2 weeks postoperatively. The incidence of rejection was 14.5% for group 1 vs. 8.5% for group 2 patients. To avoid confounding variable associated with the rejection treatment, any patient with rejection was excluded for statistical analysis, as were patients with follow- up less than 30 days. The final study group for analysis included 350 patients: 235 with Basiliximab induction (group 1) and 115 rATG induction (group 2). The mean follow-up was 21.8 +/- 11 months. Differences in the incidences of postoperative hernia, wound infections, or lymphoceles requiring any form of drainage were analyzed for statistical significance using the chi-square test. RESULTS: The percentage of patients with wound complications was 26.0% versus 39.1% (P < .025) for group 1 versus group 2, respectively. Incisional hernias occurred in 10.6% versus 18.3% patients (P < .05), wound infections in 11.1% versus 16.5% (P = NS), and lymphoceles in 10.6% versus 15.9% (P = NS) for the two groups, respectively. CONCLUSIONS: rATG-induced renal transplants recipients treated with sirolimus, cyclosporine, and steroids show a significantly increased incidence of postoperative incisional hernias and a trend toward a greater number of lymphocele and wound infection complications.

Adult↗

Cyclosporin A-induced changes in endogenous metabolites in rat urine: a metabonomic investigation using high field 1H NMR spectroscopy, HPLC-TOF/MS and chemometrics.

The model nephrotoxin cyclosporin A was administered to male Wistar-derived rats daily for 9 days at a dose level of 45 mg/kg per day. Urine samples were collected daily and the excretion pattern of low molecular mass organic molecules in the urine was studied using 1H NMR spectroscopy and HPLC-TOF/MS. Distinct changes in the pattern of endogenous metabolites, as a result of the daily administration of cyclosporin A, were observed by 1H NMR from day 7 onwards. The NMR-detected markers included raised concentrations of glucose, acetate, trimethylamine and succinate and reduced amounts of trimethylamine-N-oxide. In parallel studies by HPLC-TOF/MS a reduction in the quantities of kynurenic acid, xanthurenic acid, citric acid and riboflavin present in the urines was noted, together with reductions in a number of as yet unidentified compounds. In addition, signals resulting from the polyethylene glycol, present in the dosing vehicle, and cyclosporin A metabolites were detected by MS. However, these were excluded from the subsequent multivariate data analysis in order to highlight only changes to the endogenous metabolites. Analysis of both the 1H NMR and HPLC-MS spectroscopic data using pattern recognition techniques clearly identified the onset of changes due to nephrotoxicity.

Animals↗

A metabonomic investigation of the biochemical effects of mercuric chloride in the rat using 1H NMR and HPLC-TOF/MS: time dependent changes in the urinary profile of endogenous metabolites as a result of nephrotoxicity.

The effects of the administration of a single dose of the model nephrotoxin mercuric chloride (2.0 mg kg(-1), subcutaneous) to male Wistar-derived rats on the urinary metabolite profiles of a range of endogenous metabolites has been investigated using (1)H NMR and HPLC-MS. Urine samples were collected daily for 9 days from both dosed and control animals. Analysis of these samples revealed marked changes in the pattern of endogenous metabolites as a result of HgCl(2) toxicity. Peak disturbances in the urinary metabolite profiles were observed (using both NMR and HPLC-MS) at 3 days post dose. Thereafter the urinary metabolite profile gradually returned to a more normal composition. Markers of toxicity identified by (1)H NMR spectroscopy were raised concentrations of lactate, alanine, acetate, succinate, trimethylamine (TMA), and glucose. Reductions in the urinary excretion of citrate and alpha-ketoglutarate were also seen. Markers identified by HPLC-MS, in positive ion mode, were kynurenic acid, xanthurenic acid, pantothenic acid and 7-methylguanine which decreased after dosing. In addition an ion at m/z 188, probably 3-amino-2-naphthoic acid, was observed to increase after dosing. As well as these identified compounds other ions at m/z 297 and 267 decreased after dosing. In negative ion mode a range of sulfated compounds were observed, including phenol sulfate and benzene diol sulfate, which decreased after dosing. As well as the sulfated components an unidentified glucuronide at m/z 326 was also observed to decrease after dosing. The results of this study demonstrate the complementary nature of the NMR and MS-based techniques for metabonomic analysis.

Acetates↗

Do men benefit more than women from an interventional strategy in patients with unstable angina or non-ST-elevation myocardial infarction? The impact of gender in the RITA 3 trial.

AIMS: The RITA 3 trial randomized patients with non-ST-elevation myocardial infarction or unstable angina to strategies of early intervention (angiography followed by revascularization) or conservative care (ischaemia or symptom driven angiography). The aim of this analysis was to investigate the impact of gender on the effect of these two strategies. METHODS AND RESULTS: In total, 1810 patients (682 women and 1128 men) were randomized. The risk factor profile of women at presentation was markedly different to men. There was evidence that men benefited more from an early intervention strategy for death or non-fatal myocardial infarction at 1 year (adjusted odds ratios 0.63, 95% confidence interval 0.41-0.98 for men and 1.79, 95% confidence interval 0.95-3.35 for women; interaction p-value=0.007). Men who underwent the assigned angiogram were more likely to be put forward for coronary artery bypass surgery, even after allowing for differences in disease severity. CONCLUSION: An early intervention strategy resulted in a beneficial effect in men which was not seen in women although caution is needed in interpretation. Further research is needed to evaluate why women do not appear to benefit from early intervention and to identify treatments that improve the prognosis of women.

Angina, Unstable↗

Prion diseases.

Explore the source record for details and available documents.

Blood Component Transfusion↗

The normal population distribution of PRNP codon 129 polymorphism.

OBJECTIVES: The common prion protein gene (PRNP) codon 129 polymorphism modifies the susceptibility to and the phenotype of prion diseases. However, no truly representative normal population-based data, or data stratified according to age or gender are available on the distribution of this polymorphism. MATERIAL AND METHODS: Allelic variation of codon 129 in three Finnish populations representing different age groups, and among Finnish, British and Irish blood donors were examined. RESULTS: The PRNP codon 129 genotype distribution in the total Finnish sample was 49% for methionine-methionine (MM), 42% for methionine-valine (MV) and 9% for valine-valine (VV), for the UK blood donors 42% for MM, 47% for MV and 11% for VV, and for the Irish blood donors 34% for MM, 56% for MV, and 10% for VV. CONCLUSIONS: The genotype frequencies were almost identical in all three Finnish populations of different ages, with no gender differences, and did not differ from corresponding figures for the Finnish blood donors. However, the PRNP codon 129 genotype distribution in Finland differed significantly from that of the British and the Irish blood donors and the previously published blood donor data on other Western Europeans and Americans.

Adolescent↗

Maternal and neonatal hair mercury concentrations: the effect of dental amalgam.

OBJECTIVE: To evaluate maternal and fetal hair mercury levels in relation to the placement of dental amalgam tooth restorations. DESIGN: Cross sectional study involving women who never had dental amalgam restorations placed, women who had amalgam restorations placed before pregnancy and women who had restorations placed during the index pregnancy. SETTING: North of England Maternity Hospital. SAMPLE: Fifty-three healthy women who delivered healthy babies at term. METHODS: Maternal and fetal hair was collected in a standardised manner in the first few days following delivery. MAIN OUTCOME MEASURES: Maternal and neonatal hair mercury concentrations. RESULTS: When compared with women without restorations, there was a significant increase in the maternal hair mercury concentration in women who had dental amalgam placed outside of the index pregnancy and also in women who had dental amalgam placed during the index pregnancy. The fetal hair mercury concentration was significantly higher in babies when mothers had been exposed to dental amalgam either before pregnancy or during pregnancy compared with unexposed babies. There was no difference in the maternal or fetal hair mercury levels in the groups of patients who had dental amalgam placed before or during pregnancy. CONCLUSIONS: Maternal and fetal hair mercury levels were significantly higher in women who previously had dental amalgam restorations placed. There was no evidence that placement of dental amalgam restorations in pregnant women who had already similar restorations increased the maternal or fetal hair mercury level.

Adult↗

Increased CSF levels of prostaglandin E(2) in variant Creutzfeldt-Jakob disease.

The concentration of the cyclooxygenase product prostaglandin E(2) was sixfold higher in CSF samples from 18 cases of variant Creutzfeldt-Jakob disease (CJD) than in a group of eight subjects with other noninflammatory neurologic diseases, and comparable to those found in a group of six patients affected by diseases with a known inflammatory component. This finding suggests that cyclooxygenase activity may have a role in variant CJD pathogenesis, as previously reported in sporadic CJD.

Adult↗