A convenient approach for a controlled and high-yield synthesis of copper-deficient Cu3–x P (0.1 < x < 0.7) is reported that makes use of ionic liquids with highly nucleophilic “naked” halide anions. ...Halide anions drastically enhance the reactivity of the white phosphorus precursor and kinetically disfavor the formation of phosphorus-rich side products. Cu3–x P shows a high degree of tolerance for cation vacancies without major structural reorganization, as evidenced by X-ray diffraction and solid-state nuclear magnetic resonance spectroscopy. Measurements of the electric properties reveal that Cu3–x P is a bad metallic p-type conductor. The resistivity is composition-dependent and displays a distinct anomaly from a phase transition, leading to the discovery and structural characterization of two hitherto unknown low temperature polymorphs. Electrochemical evaluation of copper-deficient Cu3–x P as anode material for lithium ion batteries reveals a drastic change in the cycling mechanism leading to an increase of the initial capacities by about 70%. This work gives a comprehensive insight into the chemical and structural features of copper-deficient Cu3–x P and should lead to an improved understanding of its properties, not just for battery applications.
Summary
Aims Microalbuminuria and, to a lesser extent, renal tubular proteins are widely used in the early detection of incipient nephropathy in diabetes mellitus. Recent reports have indicated ...detrimental effects of storage at −20°C on urine proteins. This study investigated the effects of storage on the measurement of urine proteins and discusses implications for the interpretation of data.
Methods Two‐hundred and sixty‐eight specimens, collected from children with Type 1 diabetes, split into duplicate aliquots and stored at −20°C and −70°C, respectively, for 6–8 months, were analysed for albumin, retinol binding protein, N‐acetyl glucosaminidase and creatinine, in the same assays to eliminate inter‐assay variability. Two independent non‐diabetic cohorts of children provided urine specimens, which were stored at −20°C for one cohort and −70°C for the other, to determine normal ranges for urine proteins.
Results Storage at −20°C led to a variable underestimation of all three urine proteins in 20% of specimens. Creatinine was unaffected. This underestimation was greater in more concentrated urine (r2 = 0.38, P < 0.001, n = 262). Consequently storage at −20°C increased the variance of the albumin/creatinine ratio more than the variance of albumin concentration. Temperature of storage affected the normal range, which was 0.1–2.1 mg/mmol at −20°C compared to 0.3–3.1 mg/mmol at −70°C. The prevalence of microalbuminuria (> 2
sd above the geometric mean in non‐diabetic specimens stored at −20°C) was 27% after storage at −70°C vs. 24% after − 20°C. The prevalence of microalbuminuria (> 2
sd above the geometric mean in non‐diabetic specimens stored at −70°C) was 21% after storage at −70°C vs. 17% after −20°C.
Conclusions Urine proteins are significantly but variably underestimated after storage at − 20 °C. These effects account for increased variance and differences in the normal range, but have less effect on the detection of microalbuminuria than might be predicted.
Multidrug resistance (MDR) contributes to limited treatment results in human hepatoblastoma (HB). The MDR1 gene and its product P-glycoprotein (P-gP) has been identified as important factor in this ...development. In other tumors, P-gP modulation leads to a restored chemosensitivity of the cells. The aim of this study was to analyze the P-gP-modulating effects of PSC 833, a cyclosporine derivate, and verapamil on the chemotherapy of HB in vivo. HB from 2 patients were transplanted subcutaneously into nude mice NMRI (nu/nu). Animals were divided into 7 groups: Group 1 (Control); Group 2 (CDDP); Group 3 (DOXO); Group 4 (DOXO + verapamil); Group 5 (DOXO + PSC 833); Group 6 (CDDP + verapamil); and Group 7 (CDDP + PSC 833). If DOXO was administered (regardless of the combination), the dose was two times 60 mg/m2. If CDDP was administered, the dose was two times 27 mg/m2. When the chemosensitizers were administered, the doses for PSC 833 and for verapamil were four times 5 mg/kg boyweight. In the combined treatment groups the chemosensitizers were given ten minutes prior to CDDP and DOXO. Tumor volume developments and α-fetoprotein (AFP) alterations were assessed. Relative expression levels of the MDR1 gene after treatment were determined using a semiquantitative rT-PCR approach. In a mixed HB, both chemosensitizers combined with DOXO or CDDP produced a significant reduction of tumor growth (p =. 0001-.00063) and AFP levels (p =. 0006-.0128) compared to tumors treated with DOXO or CDDP only. Treatment results were identical to those in a less differentiated pure embryonal HB, but only in one case (DOXO + PSC 833, p =. 031) significant. The chemosensitizers had no influence on the MDR1 gene expression. MDR1 modulators improve the efficiency of DOXO and CDDP treatment in xenotransplanted HB. They do not induce a further increase of drug resistance in the tumors. The data provide evidence that chemosensitizers might improve treatment results in patients with advanced or relapsed HB.
Infants with acute leukemia, especially neonates, comprise a unique high-risk population prone to chemotherapy resistance and treatment complications. Basal levels of expression of cell death and ...cell survival factors vary greatly in different types of cancer and are key determinants of response to treatment. Until now, expression of these factors had not been evaluated in detail in acute leukemia of infants. In this study the basal expression of pro-death and pro-survival genes in the intrinsic apoptosis pathway, apoptosis execution genes and mitochondrial maintenance genes was quantified in primary leukemia cells in a large cohort of infants, and relationships between gene expression and MLL status and clinical covariates were analyzed.
Methods: Bone marrow or peripheral blood samples from the time of diagnosis were examined in 103 infants (age 1–363 d, median 177 d) with acute leukemia (63 ALL, 40 AML). White blood cell (WBC) counts ranged from 4.4–1676×103/μL (median 127.6×103/μL). MLL status was characterized by standard cytogenetics, FISH, Southern blot analysis, reverse transcriptase PCR and/or panhandle PCR approaches. The ALL cases were classified as MLL-AF4+ (n= 31), other MLL rearrangement positive (other MLL+) (n= 22) or MLL rearrangement negative (MLL−) (n= 10). Due to heterogeneity in partner genes, the AML cases were classified as MLL+ (n= 22) or MLL− (n= 18). Quantitative real time PCR analysis of total RNAs was performed using a custom TaqMan® low-density array with one or more assays, each in quadruplicate, for 35 cell death regulatory genes and 3 housekeeping genes, and ΔCT values (average cycle threshold values normalized to 18S rRNA) were computed. The Behrens-Fisher nonparametric multiple comparison test in the npmc package for R was used to determine the significance of the difference in median −ΔCT values among the three ALL groups and between the two AML groups (p<0.001 considered as significant). Relationships were sought between −ΔCT values and clinical covariates (age, sex, WBC count, CNS status, events) by computing Spearman correlation coefficients and their levels of significance.
Results: In ALL, expression of the following genes was greater in MLL-AF4+ than MLL− cases: anti-apoptotic BCL-2 and MCL-1; pro-apoptotic BAX and BID; apoptosis execution APAF1, CASP3 and CASP9; and mitochondrial maintenance COX5A, CYC1, UQCR1 and UQCR. For some of these genes, expression was also greater in other MLL+ than MLL− cases. In AML, expression of pro-apoptotic BAK and BIK was higher in MLL+ than MLL− cases. For the sample set as a whole, expression of the following genes was positively correlated with WBC count (r>0.3; p<0.01): anti-apoptotic BCL-2 and BCL-W; pro-apoptotic NOXA; apoptosis execution CASP8; and mitochondrial maintenance HCCS. The correlation between WBC count and BCL-2 was the strongest (r=0.40;p=4E-5). Only the expression of pro-apoptotic BIM was correlated with age at diagnosis and the correlation was not particularly strong (r = −0.246;p=0.01).
Conclusions: These results suggest that infant ALL and AML differ with respect to the expression of genes that regulate cell death. Furthermore, cell death regulatory gene expression is affected more by MLL translocations in infant ALL than infant AML. This finding may explain the greater impact of MLL translocations on prognosis in infant ALL than AML. The abundance of specific pro- as well as anti-apoptotic BCL-2 family mRNAs in MLL+ infant ALL is also relevant to the identification of novel therapeutic targets in this pathway. The positive correlation between anti-apoptotic BCL-2 expression and WBC count is biologically plausible and consistent with the aggressive nature of acute leukemia in infants.
Gene expression profiling has significant potential to improve risk classification and therapeutic targeting in ALL. Our goal is to develop molecular classifiers that more reliably predict relapse or ...resistance to current treatment regimens in order to identify patients who may benefit from therapeutic intensification or experimental approaches. COG P9906, testing an augmented BFM regimen, enrolled 271 patients with B precursor ALL with NCI high risk features (older age/higher WBC) who had experienced very poor outcomes (45% EFS) on prior trials. Patients with favorable (trisomy 4+10/TEL-AML1) or very unfavorable (Ph+/hypodiploidy) genetics were excluded. Expression profiles (Affymetrix HG_U133Plus2) were obtained from pre-treatment leukemic blasts in 207/271 (76%) children on COG P9906; these 207 cases were representative of the overall cohort. EFS at 4 yrs was 61% and flow cytometric measures of MRD (flow MRD) at end-induction (day 28) were highly predictive of outcome. Using expression profiles, a molecular classifier predictive of EFS was modeled using a Cox regression-based supervised principal components analysis and modified score test with extensive nested cross validation. A 42 gene molecular classifier predictive of EFS differentiated this cohort into a low (4 yr EFS: 81%, n=109) and high (4 yr EFS: 50%, n=98) molecular risk group (log rank test, P< 0.0001). In multivariate analysis, the molecular risk classifier (MRC) retained prognostic significance (likelihood ratio test, p=0.0001) when adjusted for flow MRD and WBC. The best predictive model for EFS resulted when the MRC was combined with flow MRD; the resulting low (MRC low risk, MRD-; 87% EFS), medium (MRC low risk, MRD+ or MRC high risk, MRD-; 62% EFS), and high risk (MRC high risk, MRD+; 29% EFS) groups had significant outcome differences (Fig. A). As one must wait until the end of induction to obtain flow MRD to apply the combined classifier, we next determined if we could develop a molecular classifier to predict end-induction MRD in pre-treatment samples. Using a modified t-test and diagonal linear discriminant analysis with extensive cross validation, we derived a 23 gene molecular classifier predictive of end-induction MRD (ROC Accuracy: 0.80; p <0.0001). When the molecular classifier for MRD was combined with the molecular classifier for EFS, three distinct risk groups with significantly different outcomes were similarly defined (low risk: 82% EFS, medium risk: 63% EFS; high risk: 45% EFS; Fig. B). These studies demonstrate that molecular classifiers for EFS and MRD significantly enhance risk prediction in high risk B-ALL and may allow earlier intervention in induction in particularly high risk patients. Use of molecular classifiers to modify risk-adapted therapy has the highest priority in evaluating strategies to improve outcome in children with ALL and are currently being prospectively tested in COG trials.
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