Emergence of carbon nanoscrolls from single walled carbon nanotubes: an oxidative route.

Carbon nanoscrolls (CNS), a one dimensional (1D) helical form of carbon, have received enormous attention recently due to their unique structure, superior properties and potential applications. In this work, radial merging of HiPCO single walled nanotube (SWNT) bundles and emergence of CNS are reported following a reflux action involving wet oxidation, HCl washing and annealing at 900 °C. We observe macroscopic quantities of graphene sheets (GS) in the post-treated sample and beautiful manifestation of curling and folding of the GS into CNS. Here, a simple solution based oxidative route for successful merging and exfoliation of SWNT bundles and subsequent formation of CNS are demonstrated and discussed in view of Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) studies. Direct evidence of emergence of CNS from SWNTs via synthesis of GS through a simple oxidative method is reported for the first time.

Oxidative stress responses of a freshwater fish, Labeo rohita, to a xenobiotic, bisphenol S.

Bisphenol S (BPS) is an organic chemical that has been used as a substitute for bisphenol A (BPA) in making polycarbonate plastics, epoxy resins, thermal receipt papers, and currency bills, as BPA has been reported to have dreadful effects on the living system. From this view point, the present study investigates whether BPS has the same or rather more toxic effects like BPA or not. Limited studies were carried out on the effect of BPS on fish. The hepatic antioxidant enzymes such as superoxide dismutase, catalase, glutathione S-transferase, glutathione reductase, and glutathione peroxidase (GPx), along with the nonenzymatic antioxidant, glutathione, in a freshwater fish, Labeo rohita, were selected as biomarkers. The results revealed that the sublethal exposure of BPS significantly influenced the activities of these biomarkers. Lipid peroxidation (LPO) products such as malondialdehyde and conjugate diene levels were also altered by the exposure. The alteration in the levels of antioxidants and LPO products after BPS exposure clearly showed that the fish experienced oxidative stress. Furthermore, the current study showed that BPS is a pollutant with oxidative potential by disrupting the antioxidant enzymes.

Structural stability of coplanar 1T-2H superlattice MoS2 under high energy electron beam.

Coplanar heterojunctions composed of van der Waals layered materials with different structural polymorphs have drawn immense interest recently due to low contact resistance and high carrier injection rate owing to low Schottky barrier height. Present research has largely focused on efficient exfoliation of these layered materials and their restacking to achieve better performances. We present here a microwave assisted easy, fast and efficient route to induce high concentration of metallic 1T phase in the original 2H matrix of exfoliated MoS2 layers and thus facilitating the formation of a 1T-2H coplanar superlattice phase. High resolution transmission electron microscopy (HRTEM) investigations reveal formation of highly crystalline 1T-2H hybridized structure with sharp interface and disclose the evidence of surface ripplocations within the same exfoliated layer of MoS2. In this work, the structural stability of 1T-2H superlattice phase during HRTEM measurements under an electron beam of energy 300 keV is reported. This structural stability could be either associated to the change in electronic configuration due to induction of the restacked hybridized phase with 1T- and 2H-regions or to the formation of the surface ripplocations. Surface ripplocations can act as an additional source of scattering centers to the electron beam and also it is possible that a pulse train of propagating ripplocations can sweep out the defects via interaction from specific areas of MoS2 sheets.

Starch digestibility and glycemic index of Paranthas supplemented with Citrus maxima (Burm.) Merr. fruit segments.

The present investigation was undertaken to develop paranthas suiting diabetic population with added health benefits. Paranthas were prepared using fresh and dry segments of pomelo. The increase in the concentration of segments decreased the texture value from 1080 to 1022 g force (fresh segments) and 1005 to 870 g force (dry segments). Naringin along with other bioactive compounds were retained to a greater extent in Paranthas containing dry pomelo fruit segments. Paranthas prepared using 20% (fresh) and 5% (dry) were sensorily acceptable. The pomelo incorporated paranthas had higher levels of resistance starch fractions (12.94%) with low predicted glycemic index (49.89%) compared to control Paranthas at 5.54 and 58.64% respectively. The fortified paranthas with an considerable content of bioactive compounds and low glycemic index indicate the possibility of using it as a dietary supplement. Thus utilization of pomelo fortification helps in improving the nutritional and functional property of paranthas suiting diabetes as well as general population.

Enhanced Risk Stratification for Children and Young Adults with B-Cell Acute Lymphoblastic Leukemia: A Children's Oncology Group Report.

Current strategies to treat pediatric acute lymphoblastic leukemia rely on risk stratification algorithms using categorical data. We investigated whether using continuous variables assigned different weights would improve risk stratification. We developed and validated a multivariable Cox model for relapse-free survival (RFS) using information from 21199 patients. We constructed risk groups by identifying cutoffs of the COG Prognostic Index (PICOG) that maximized discrimination of the predictive model. Patients with higher PICOG have higher predicted relapse risk. The PICOG reliably discriminates patients with low vs. high relapse risk. For those with moderate relapse risk using current COG risk classification, the PICOG identifies subgroups with varying 5-year RFS. Among current COG standard-risk average patients, PICOG identifies low and intermediate risk groups with 96% and 90% RFS, respectively. Similarly, amongst current COG high-risk patients, PICOG identifies four groups ranging from 96% to 66% RFS, providing additional discrimination for future treatment stratification. When coupled with traditional algorithms, the novel PICOG can more accurately risk stratify patients, identifying groups with better outcomes who may benefit from less intensive therapy, and those who have high relapse risk needing innovative approaches for cure.

Low reflectance of carbon nanotube and nanoscroll-based thin film coatings: a case study.

Research on carbon material-based thin films with low light reflectance has received significant attention for the development of high absorber coatings for stray light control applications. Herein, we report a method for the successful fabrication of stable thin films comprised of carbon nanotubes (CNTs) and nanoscrolls (CNS) on an aluminium (Al) substrate, which exhibited low reflectance of the order of 2-3% in the visible and near-infrared (NIR) spectral bands. Changes in the structural and chemical composition of pristine single-walled carbon nanotube (SWCNT) samples were analyzed after each processing step. Spectroscopy, microscopy and microstructural studies demonstrated emergence of CNS and multi-walled carbon nanotubes (MWCNTs) due to the sequential chemical processing of the sample. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) studies revealed the formation of CNS via curling and folding of graphene sheets. Microstructural investigations including SEM and atomic force microscopy (AFM) confirmed the presence of microcavities and pores on the surface of the film. These cavities and pores significantly contribute to the observed low reflectance value of CNTs, CNS compound films by trapping the incident light. Fundamental space environmental simulation tests (SEST) were performed on the coated films, that showed promising results with reflectance values almost unaltered in the visible and NIR spectral bands, demonstrating the durability of these films as potential candidates to be used in extreme space environmental conditions. This study describes the preparation, characterization, and testing of blended CNT and CNS coatings for low-light scattering applications.

Correction: Standardisation and consensus guidelines for minimal residual disease assessment in Philadelphia-positive acute lymphoblastic leukemia (Ph+ALL) by real-time quantitative reverse transcriptase PCR of e1a2 BCR-ABL1.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Standardisation and consensus guidelines for minimal residual disease assessment in Philadelphia-positive acute lymphoblastic leukemia (Ph + ALL) by real-time quantitative reverse transcriptase PCR of e1a2 BCR-ABL1.

Minimal residual disease (MRD) is a powerful prognostic factor in acute lymphoblastic leukemia (ALL) and is used for patient stratification and treatment decisions, but its precise role in Philadelphia chromosome positive ALL is less clear. This uncertainty results largely from methodological differences relating to the use of real-time quantitative PCR (qRT-PCR) to measure BCR-ABL1 transcript levels for MRD analysis. We here describe the first results by the EURO-MRD consortium on standardization of qRT-PCR for the e1a2 BCR-ABL1 transcript in Ph + ALL, designed to overcome the lack of standardisation of laboratory procedures and data interpretation. Standardised use of EAC primer/probe sets and of centrally prepared plasmid standards had the greatest impact on reducing interlaboratory variability. In QC1 the proportion of analyses with BCR-ABL1/ABL1 ratios within half a log difference were 40/67 (60%) and 52/67 (78%) at 10-3 and 36/67 (53%) and 53/67 (79%) at 10-4BCR-ABL1/ABL1. Standardized RNA extraction, cDNA synthesis and cycler platforms did not improve results further, whereas stringent application of technical criteria for assay quality and uniform criteria for data interpretation and reporting were essential. We provide detailed laboratory recommendations for the standardized MRD analysis in routine diagnostic settings and in multicenter clinical trials for Ph + ALL.

Inverted duplication pattern in anaphase bridges confirms the breakage-fusion-bridge (BFB) cycle model for 11q13 amplification.

The homogeneously staining region (hsr) involving chromosome band 11q13 includes amplified genes from this chromosome segment and carries a relatively poor prognosis in oral squamous cell carcinomas (OSCC), with shorter time to recurrence and reduced overall survival. We previously identified an inverted duplication pattern of genes within the 11q13 hsr in OSCC cells, supporting a breakage-fusion-bridge (BFB) cycle model for gene amplification. To validate our hypothesis that 11q13 gene amplification in OSCC occurs via BFB cycles, we carried out fluorescence in situ hybridization (FISH) using probes for band 11q13 on 29 OSCC cell lines. We demonstrate that all OSCC cell lines with 11q13 amplification express a significantly higher frequency of anaphase bridges containing 11q13 sequences compared to cell lines without amplification, providing further experimental evidence that 11q13 gene amplification in OSCC cells occurs via BFB cycles. Elucidation of mechanisms responsible for initiating and promoting gene amplification provides opportunities to identify new biomarkers to aid in the diagnosis and prognosis of oral cancer, and may be useful for developing novel therapeutic strategies for patients with OSCC.

Starch digestibility and predicted glycemic index in the bread fortified with pomelo (Citrus maxima) fruit segments.

The aim of this study was to evaluate the starch digestibility and predicted glycemic index in breads incorporated with pomelo fruit (Citrus maxima) segments. Volume of the white and brown breads supplemented with pomelo fresh segments increased, while the crumb firmness decreased. Bread with 20% fresh and 5% dry pomelo segments were sensorily acceptable. Bioactive components such as phenolics, flavonoids, naringin and carotenoids were retained to a greater extent in bread containing dry pomelo segments. The pomelo incorporated bread had higher levels of resistant starch fractions (3.87-10.96%) with low predicted glycemic index (62.97-53.13%), despite their higher total starch (69.87-75.47%) content compared to control bread. Thus pomelo segments in the product formulations lowered the glycemic index probably by inhibiting carbohydrate hydrolyzing enzyme activity which could be attributed to naringin. Hence fortified bread prepared from pomelo fruit segment is recommended to gain nutritional value and to decrease the risk of diabetes.

Chromosomal instability in oral cancer cells.

Chromosomal instability is a common feature of human tumors, including oral cancer. Although a tumor karyotype may remain quite stable over time, chromosomal instability can lead to 'variations on a theme' of a clonal cell population, often with each cell within a tumor possessing a different karyotype. Thus, chromosomal instability appears to be an important acquired feature of tumor cells, since propagation of such a diverse cell population may facilitate evasion of standard therapies. There are several sources of chromosomal instability, although the primary causes appear to be defects in chromosomal segregation, telomere stability, cell-cycle checkpoint regulation, and the repair of DNA damage. Our understanding of the biological basis of chromosomal instability in cancer cells is increasing rapidly, and we are finding that the seemingly unrelated origins of this phenomenon may actually be related through the complex network of cellular signaling pathways. Here, we review the general causes of chromosomal instability in human tumors. Specifically, we address the state of our knowledge regarding chromosomal instability in oral cancer, and discuss various mechanisms that enhance the ability of cancer cells within a tumor to express heterogeneous karyotypes. In addition, we discuss the clinical relevance of factors associated with chromosomal instability as they relate to tumor prognosis and therapy.

Combination of Anti-Diabetic Drug Metformin and Boswellic Acid Nanoparticles: A Novel Strategy for Pancreatic Cancer Therapy.

Pancreatic cancer has an infaust prognosis and is the fourth common cause of cancer related death in India. It is highly resistant to conventional treatment modalities such as chemotherapy, radiation therapy and surgery. The association of pancreatic cancer and diabetes mellitus is explored in our study. Pancreatic cancer is more likely to occur in people who have diabetes than people devoid of it, which is supported by the observation that hyperglycaemia occurs at an early stage of pancreatic cancer and is indeed a risk factor. In the present study, we have demonstrated a synergistic relationship between metformin and boswellic acid nanoparticles with varying doses of boswellic acid nanoparticles and constant metformin (20 mM). The effect revealed increased synergism between metformin and boswellic acid nanoparticles through the inhibition of cell proliferation with an effect of 80% for the combination with 0.3 mg/mL and 0.4 mg/mL and a constant concentration of metformin. We examined the effect of combination on cell migration which revealed time dependent inhibitory effect on pancreatic cell line (MiaPaCa-2). Also, we found that the combinatorial approach significantly decreased colony formation and exhibited high rate of induction of apoptosis through DNA fragmentation in pancreatic cancer cells. In-vitro hemolysis confirmed the hemocompatibility of the combination therapy with metformin and boswellic acid nanoparticles. Flow cytometry based apoptosis assay and Caspase mediated apoptosis proved apoptosis mediated cell death. Further, the cells were analysed with mitochondrial membrane potential kit which revealed depolarization of mitochondrial membrane potential due to apoptosis after treatment with drug combination. Hence, the combination approach proved to be a promising therapy towards pancreatic cancer.

Increased karyotype precision using fluorescence in situ hybridization and spectral karyotyping in patients with myeloid malignancies.

We studied seven patients with various malignant hematologic disorders using fluorescence in situ hybridization (FISH) and one of these patients with spectral karyotyping (SKY). With appropriate probes, the t(8;21) and inv(16) were confirmed in two patients and the karyotypic precision was increased in five others using FISH and SKY. Two of three patients with 12p rearrangements had a deletion of one TEL allele. Thus, these newer techniques are an important adjunct to accurate chromosome analysis in malignancy.

Variant three-way translocation of inversion 16 in AML-M4Eo confirmed by fluorescence in situ hybridization analysis.

The inv(16) and t(16;16) characterize a subgroup of acute myelomonocytic leukemia (AML) with distinct morphological features and a favorable prognosis. Both cytogenetic abnormalities result in a fusion of CBF beta at 16q22 and MYH11 gene at 16p13, whose detection by PCR and fluorescence in situ hybridization (FISH) is useful for diagnosis and monitoring of the disease. Variant translocations of inv(16)/t(16;16) are very rare and whether they are also associated with a favorable prognosis is unknown. We report a patient presenting with typical AML-M4Eo and a three-way translocation of inv(16) involving 16p13, 16q22, and 3q22. FISH studies on bone marrow (BM) chromosomes using CBFB and MYH11 DNA probes revealed a fusion of CBFB and MYH11 on 16q of the der(16), as well as a signal from MYH11 on 16p but not from CBFB; normal signals for both probes were present on the normal 16. Neither of these labeled probes was on the der(3), but the translocation between the der(3) and der(16) was confirmed by using a chromosome 16 painting probe. Molecular analysis of BM cells using RT-PCR identified a CBFB-MYH11 fusion transcript type D. After achieving complete remission, the patient relapsed. We conclude that FISH and PCR are feasible tools to distinguish cases with variant abnormalities of inv(16) from cases with other chromosome 16 abnormalities. Variant abnormalities of inv(16) may be not associated with favorable prognosis.

Susceptibility of Plasmodium falciparum to a combination of thymidine and ICI D1694, a quinazoline antifolate directed at thymidylate synthase.

Unlike mammalian cells, malarial parasites lack the enzymes to salvage preformed pyrimidines. For this reason, a combination of a thymidylate synthase inhibitor and the nucleoside thymidine should provide selective antimalarial activity even in the absence of any known active site differences between malarial and mammalian thymidylate synthases. To test this hypothesis, we evaluated the in vitro antimalarial activity of ICI D1694, a quinazoline antifolate that inhibits thymidylate synthase in mammalian cells. ICI D1694 inhibited the in vitro proliferation of Plasmodium falciparum with a 50% inhibitory concentration of 20 microM. As predicted, this antimalarial activity was not affected by the presence of 10 microM thymidine in the culture medium. In contrast, five different mammalian cells, several of which were susceptible to nanomolar levels of ICI D1694 in the absence of thymidine, were rescued by thymidine. At doses of 100 microM ICI D1694 and 10 microM thymidine, the proliferation of parasites was completely inhibited, but the proliferation of all mammalian cells remained unaffected. A test of susceptibility patterns among five different isolates of P. falciparum revealed that strains resistant to pyrimethamine, cycloguanil, or chloroquine had susceptibilities to ICI D1694 essentially the same as those of wild-type parasites. These findings are consistent with the hypothesis that, intracellularly, ICI D1694 inhibits P. falciparum thymidylate synthase. Overall, it is clear that even with an inhibitor of malarial thymidylate synthase that is not particularly effective in itself, one can obtain selective inhibition of parasites if the antimalarial agent is used in combination with thymidine. More effective inhibitors of malarial thymidylate synthase will undoubtedly lead to selective chemotherapy in vivo.

Spectral karyotype analysis of T-cell acute leukemia.

Analysis of 15 cases of T-cell acute lymphoblastic leukemia with spectral karyotyping (SKY), which can identify all chromosomes simultaneously, clarified the chromosome rearrangements in 3 cases and confirmed them in 11 others; no abnormal cells were identified in 1 case, which had only 10% abnormal cells. Five of the latter cases had a normal karyotype. Thus, the use of SKY substantially improves the precision of karyotype analysis of malignant cells, which in turn leads to a more accurate assessment of the genotypic abnormalities in those cells.

MLL is fused to CBP, a histone acetyltransferase, in therapy-related acute myeloid leukemia with a t(11;16)(q23;p13.3).

The recurring translocation t(11;16)(q23;p13.3) has been documented only in cases of acute leukemia or myelodysplasia secondary to therapy with drugs targeting DNA topoisomerase II. We show that the MLL gene is fused to the gene that codes for CBP (CREB-binding protein), the protein that binds specifically to the DNA-binding protein CREB (cAMP response element-binding protein) in this translocation. MLL is fused in-frame to a different exon of CBP in two patients producing chimeric proteins containing the AT-hooks, methyltransferase homology domain, and transcriptional repression domain of MLL fused to the CREB binding domain or to the bromodomain of CBP. Both fusion products retain the histone acetyltransferase domain of CBP and may lead to leukemia by promoting histone acetylation of genomic regions targeted by the MLL AT-hooks, leading to transcriptional deregulation via aberrant chromatin organization. CBP is the first partner gene of MLL containing well defined structural and functional motifs that provide unique insights into the potential mechanisms by which these translocations contribute to leukemogenesis.

Heterogeneity in the breakpoints in balanced rearrangements involving band 12p13 in hematologic malignancies identified by fluorescence in situ hybridization: TEL (ETV6 ) is involved in only one half.

Using fluorescence in situ hybridization (FISH) and probes located on 12p12.1 to 13.3, we studied the breakpoints of 23 patients who had various hematologic malignant diseases and who had 12p13-balanced translocations (21 patients), inversion (1 patient), or insertion (1 patient). Among them, 14 patients had breakpoints within YAC964c10, which contains the TEL (ETV6 ) gene and in 12 of these with balanced translocations or insertion, the FISH results suggested that TEL was involved. Two of the 14 patients, patients no. 13 and 14, had breakpoints in YAC 964C10 that were centromeric to TEL but telomeric to KIP1. In the other 9 patients whose breakpoints did not fall within the YAC, the breakpoints were found telomeric to the YAC in at least three different locations on distal 12p. These results indicated that TEL was involved in only half (12 of 23) of the patients with balanced 12p13 rearrangements and that there probably were several other breakpoint cluster regions on 12p13, suggesting that genes other than TEL were involved in these rearrangements.