Veliparib monotherapy following carboplatin/paclitaxel plus veliparib combination therapy in patients with germline BRCA-associated advanced breast cancer: results of exploratory analyses from the phase III BROCADE3 trial.

BACKGROUND: In the BROCADE3 trial, addition of the poly(ADP-ribose) polymerase inhibitor, veliparib, to carboplatin/paclitaxel improved progression-free survival (PFS) (hazard ratio 0.71, 95% confidence interval 0.57-0.88; P = 0.002) in patients with advanced human epidermal growth factor receptor 2-negative, germline BRCA1/2-mutated breast cancer. A subset of patients discontinued both carboplatin and paclitaxel before progression and continued on veliparib/placebo maintenance monotherapy until progression. Analyses in this patient subgroup are reported. PATIENTS AND METHODS: Patients were randomized 2 : 1 to veliparib plus carboplatin/paclitaxel or placebo plus carboplatin/paclitaxel. Veliparib (120 mg twice daily) or placebo was given on days -2 to 5, carboplatin (area under the curve 6 mg/ml) on day 1, and paclitaxel (80 mg/m2) on days 1, 8, and 15 of 21-day cycles. Patients who discontinued both carboplatin and paclitaxel before progression received blinded study drug monotherapy at an increased dose of 300-400 mg twice daily continuously. PFS was the primary endpoint. Exploratory analyses were carried out in the subgroup of patients who received blinded study drug as monotherapy. A time-varying Cox model including data from all patients was also used to evaluate treatment effect in the combination and monotherapy phases. RESULTS: A total of 136 of 337 patients randomized to veliparib plus carboplatin/paclitaxel and 58/172 patients randomized to placebo plus carboplatin/paclitaxel discontinued both carboplatin and paclitaxel before progression and continued on blinded veliparib or placebo monotherapy. In this blinded monotherapy subgroup, investigator-assessed median PFS from randomization was 25.7 months with veliparib versus 14.6 months with placebo. Hazard ratios from a time-varying Cox model favored veliparib during both combination therapy and monotherapy. Any-grade adverse events occurring in the monotherapy phase were primarily gastrointestinal. The most common grade ≥3 adverse events were neutropenia and anemia (4% each with veliparib; 5% and 2%, respectively, with placebo). CONCLUSIONS: Veliparib maintenance monotherapy had a tolerable safety profile and may extend PFS following combination chemotherapy.

Arsenic load in rice ecosystem and its mitigation through deficit irrigation.

Rice the staple food is a notable intake source of arsenic to the rural population of eastern India through food-chain. A field survey was carried out to study the variation of arsenic load in different parts of rice genotype Shatabdi (most popular genotype of the region) exposed to varying level of arsenic present in the irrigation water and soil. As irrigation is the primary source of arsenic contamination, a study was conducted to assess arsenic load in rice ecosystem under deficit irrigation practices like intermittent ponding (IP), saturation (SAT) and aerobic (AER) imposed during stress allowable stage (16-40 days after transplanting) of the crop (genotype Shatabdi). Present survey showed that arsenic content in water and soil influenced the arsenic load of rice grain. Variation in arsenic among different water and soil samples influenced grain arsenic load to the maximum extent followed by straw. Deviation in root arsenic load due to variation in water and soil arsenic content was lowest. Arsenic concentration of grain is strongly related to the arsenic content of both irrigation water and soil. However, water has 10% higher impact on grain arsenic load over soil. Translocation of arsenic from root to shoot decreased with the increase in arsenic content of water. Imposition of saturated and aerobic environment reduced both yield and grain arsenic load. In contrast under IP a marked decrease in grain arsenic content recorded with insignificant reduction in yield. Deficit irrigation resulted in significant reduction (17.6-25%) in arsenic content of polished rice and the values were lower than that of the toxic level (<0.2 mg kg-1). In contrast the decrease in yield was to the tune of 0.9% under IP regime over CP.

Enhanced x-ray emission from nano-particle doped bacteria.

Recently, it has been greatly appreciated that intense light matter interaction is modified due to the nano- and microstructures in the target by--surface plasmons, laser energy localization scattering etc. Extreme laser intensities produce dense plasmas and collective mechanisms generate energetic electrons, ions and hard x-rays. Recently, it is postulated that the anharmonic electron motion, driven by ultrashort, high-intensity laser pulses, provides a universal mechanism for the laser absorption. Here, we provide the first demonstration of anharmonic-resonance-aided high laser-absorption in a biological system. At intensities of ∼ 10¹6⁻¹8 W/cm², 40 fs pulses excite a plasma formed with E. coli bacteria. The density-inhomogeneities due to the micro- and nanostructures in the bacterial target increase anharmonic resonance (AHR) heating and result in a 104-fold enhancement in the hard x-ray yield compared to plain solid targets. These observations lead to novel high-energy x-ray sources that have implications to lithography, imaging and medical applications.

Ternary composites of poly(vinylidene fluoride-co-hexafluoropropylene) with silver nanowires and titanium dioxide nanoparticles as separator membranes for lithium-ion batteries.

In the realm of polymer composites, there is growing interest in the use of more than one filler for achieving multifunctional properties. In this work, a composite separator membrane has been developed for lithium-ion battery application, by incorporating conductive silver nanowires (AgNWs) and titanium dioxide (TiO2) nanoparticles into a poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) polymer matrix. The composite membranes were manufactured by solvent casting and thermally induced phase separation, with total filler content varying up to 10 wt%. The ternary composites composites present improved mechanical characteristics, ionic conductivity and lithium transfer number compared to the neat polymer matrix. On the other hand, the filler type and content within the composite has little bearing on the morphology, polymer phase, or thermal stability. Once applied as a separator in lithium-ion batteries, the highest discharge capacity value was obtained for the 5 wt% AgNWs/5 wt% TiO2/PVDF-HFP membrane at different C-rates, benefiting from the synergetic effect from both fillers. This work demonstrates that higher battery performance can be achieved for next-generation lithium-ion batteries by using separator membranes based on ternary composites.

A bright point source of ultrashort hard x-ray pulses using biological cells.

We demonstrate that the interaction of intense femtosecond light on a plain solid substrate can be substantially altered by a few micron layer coating of bacterial cells, live or dead. Using E. Coli cells, we show that at an intensity of 10(16)W cm(-2), the bremsstraahlung hard x-ray emission (up to 300 keV), is increased by more than two orders of magnitude as compared to a plain glass slab. Particle-in-cell simulations carried out by modeling the bacterial cells as ellipsoidal particles show that the hot electron generation is indeed enhanced by the presence of microstructures. This new methodology should pave way for using microbiological systems of varied shapes to control intense laser produced plasmas for EUV/x-ray generation.

Laser intensity profile based terahertz field enhancement from a mixture of nano-particles embedded in a gas.

Nano-particle embedded system plays an importance in developing of future terahertz (THz) radiation source for real-world applications. The laser interactions with nanoparticle embedded system can produce a wide range of THz radiation due to plasma oscillations excitation. We investigate THz field generation from the laser-beat wave interaction with a mixture of spherical and cylindrical graphite nanoparticles in argon gas. Different laser intensity distributions such as Gaussian, cosh-Gaussian, flat-top and ring shape laser pulses have been studied in this work. The relevant plasmon resonance conditions with appropriate symmetry of spherical nanoparticles and cylindrical nanoparticles are discussed. THz field is enhanced upto the order of 10 2 when the laser intensity redistributes along the polarization direction for a ring shape field envelope.

THREE-POINT AREA METHOD FOR THERMOLUMINESCENCE GLOW CURVE ANALYSIS AND ITS APPLICATION TO THE GLOW PEAK OF K2SRP2O7:PR.

A method has been proposed to evaluate the kinetic parameters, viz. activation energy ($E$) and order of kinetics ($b$) from a single or isolated thermoluminescence (TL) glow peak. Along with the area under the entire curve, this method uses a set of three arbitrary data points and calculates the partial area under the curve from each point to the endpoint. In this way, the entire information associated with the curve is used and the method is named as 'Three-Point Area' (TPA) method. We have applied it successfully on a number of theoretically simulated TL curves generated in One Trap One Recombination centre (OTOR) model and General-Order Kinetics (GOK) model under quasi-equilibrium approximations with linear heating scheme. The activation energies are found in good agreement with input values for both the models. For OTOR model, temperature average of order of kinetics is estimated to compare with the present result. Systematic analysis is carried out for estimation of errors inherent in the method in the purview of GOK model. A closer look on the results reveals that any set of three points, preferably chosen from the rising side of the curve, can yield activation energy and order of kinetics. The validity of the method to extract $E$ and $b$ from experimental glow curves is exemplified by considering experimental TL data reported in literature. Finally, a complete study starting from the synthesis of a new phosphor $\mathrm{K_2SrP_2O_7:Pr} $ and analysis of the recorded TL data to estimate $E$ and $b$ employing the TPA method has been reported.

The sun and nearby stars: microwave observations at high resolution.

High-resolution microwave observations are providing new insights into the nature of active regions and eruptions on the sun and nearby stars. The strength, evolution, and structure of magnetic fields in coronal loops can be determined by multiple-wavelength observations with the Very Large Array. Flare models can be tested with Very Large Array snapshot maps, which have angular resolutions of better than 1 second of arc in time periods as short as 10 seconds. Magnetic changes that precede solar eruptions on time scales of tens of minutes involve primarily emerging coronal loops and the interactions of two or more loops. Magnetic reconnection at the interface of two closed loops may accelerate electrons and trigger the release of microwave energy in the coronal parts of the magnetic loops. Nearby main-sequence stars of late spectral type emit slowly varying microwave radiation and stellar microwave bursts that show striking similarities to those of the sun.

Mitogenome analysis of Indian isolate of Rhipicephalus microplus clade A sensu (): A first report from Maritime South-East Asia.

This communication reports a comprehensive profile of mitogenome analysis of Rhipicephalus microplus, isolated and identified from Andaman and Nicobar islands, a part of Maritime South East Asia. Complete mitogenome of Indian isolate of R. microplus (MK234703) was 14,903 bp. Mitochondrial (mt.) genome had 13 protein coding genes (PCGs), 22 tRNAs, two ribosomal subunits and two control regions. All PCGs were located on the H-strand except nad1, nad5, nad4 and nad4L. All start codons were ATN codon and abbreviated stop codons were seen in cox-2-3, nad-5 and cytb. A purine rich tick-box motif has been identified. A tandem repeat unit (TTTATT), described as a region alike to nad1 was identified in 130 bp insertion in between nad1 and tRNA-Glu and in nad1 sequence. Presence of two control regions (CRs) proved that, two CRs have evolved in concert rather than independently. Strong biasness towards A and T in Indian isolate of R. microplus is a typical feature for most of the arthropods. Subtracted values of dn and ds suggested that, there was least effect of nt. sequence of cox1 gene when Indian isolate was compared with other isolates of Rhipicephalus. On the basis of phylogenetic analysis, species of the genus Rhipicephalus could be clustered in three groups; ticks of the genera belonging to sub-family Rhipicephalinae could be grouped in a single cluster. Finally, cox1 sequence of MK234703 indicated that the isolate belonged to clade A sensu Burger et al., 2014 which has not been reported earlier from India.

Mitochondrial landscape of indigenous pig germplasm of Andaman and Nicobar Islands.

Nicobari pig and Andaman Desi pig are indigenous pig germplasm of Andaman and Nicobar islands, India. Over the last two decades, the pig breeds witnessed a rapid decline in population, necessitating immediate characterization and conservation. The present study depicts the complete mitochondrial genome sequence of Nicobari pig and Andaman Desi pig. The mitogenomes of both the breeds encode 37 genes including 13 protein coding genes, 22 tRNAs, and two ribosomal RNA genes. In addition, a control region (D-loop) was also present. Phylogenetic analysis showed that Nicobari is phylogenetically close to Banna mini and Breed I pig, whereas Andaman Desi pig is close to Mong cai and Jinhua pig breeds. The results of the study will be helpful for formulating of conservation strategy of the native swine breeds.

The RD1-encoded antigen Rv3872 of Mycobacterium tuberculosis as a potential candidate for serodiagnosis of tuberculosis.

Tuberculosis (TB) infections in India account for one-third of the global burden, making it important to develop speedy, cost-effective diagnostic tools. This study evaluated recombinant RD1-encoded antigens of Mycobacterium tuberculosis as tools for serodiagnosis by determining the immunological reactivity of these proteins against sera from healthy, bacille Calmette-Guérin (BCG)-vaccinated and TB-infected individuals from Kolkata. Rv3872, Rv3875 (ESAT-6) and Rv3878 were able to discriminate healthy BCG-vaccinated controls from TB patients. Rv3872 showed the highest level of antibody response in comparison with other antigens, and also showed statistically significant differences between pulmonary (p <0.0001) or extra-pulmonary (p <0.001) TB patients and healthy BCG-vaccinated individuals. The levels of antibody were measured using 20-mer overlapping peptides spanning the entire Rv3872 sequence. The immunological reactivity against a mixture of two peptides (P8 and P9) encompassing amino-acids 57-84 correlated well with that obtained using full-length Rv3872. This result was explained by the fact that two of the predicted regions of high antigenicity lie within amino-acid residues 57-85 of Rv3872. The high sensitivity and specificity of Rv3872, as well as the mixture of two synthetic overlapping peptides derived from Rv3872, highlight their potential and argue in favour of their use in serodiagnosis of both pulmonary and extra-pulmonary TB.

Nuclear ULK1 promotes cell death in response to oxidative stress through PARP1.

Reactive oxygen species (ROS) may cause cellular damage and oxidative stress-induced cell death. Autophagy, an evolutionarily conserved intracellular catabolic process, is executed by autophagy (ATG) proteins, including the autophagy initiation kinase Unc-51-like kinase (ULK1)/ATG1. Although autophagy has been implicated to have both cytoprotective and cytotoxic roles in the response to ROS, the role of individual ATG proteins, including ULK1, remains poorly characterized. In this study, we demonstrate that ULK1 sensitizes cells to necrotic cell death induced by hydrogen peroxide (H2O2). Moreover, we demonstrate that ULK1 localizes to the nucleus and regulates the activity of the DNA damage repair protein poly (ADP-ribose) polymerase 1 (PARP1) in a kinase-dependent manner. By enhancing PARP1 activity, ULK1 contributes to ATP depletion and death of H2O2-treated cells. Our study provides the first evidence of an autophagy-independent prodeath role for nuclear ULK1 in response to ROS-induced damage. On the basis of our data, we propose that the subcellular distribution of ULK1 has an important role in deciding whether a cell lives or dies on exposure to adverse environmental or intracellular conditions.

GA/GC-rich sequence confers Tat responsiveness to human neurotropic virus promoter, JCVL, in cells derived from central nervous system.

The human immunodeficiency virus type I (HIV-1) nuclear protein, Tat, is a potent transactivating factor that stimulates the rate of transcription of responsive promoters. Evidently, to exert its activity, Tat requires to be localized in close proximity of the transcription initiation site. Previous studies in our laboratory have demonstrated that Tat has the capacity to increase transcriptional activity of the late gene of a human neurotropic virus JC (JCV) in glial cells. In the present study, using deletion mutation analysis, we have identified a region upstream of the JCV late RNA start sites, termed upstream target (upTAR), that positively responds to Tat activation in glial cells. Using synthetic oligonucleotides spanning the upTAR sequence linked to a heterologous promoter, we have identified a GA/GC-rich region (GGAGGCGGAGGC) that confers TAT responsiveness preferentially on glial cell lines. Using gel mobility-shift and UV cross-linking assays, we have demonstrated that four major complexes (a-d) from glial and HeLa (non-glial) cells interact with the upTAR sequence. Whereas the molecular weights of the participant proteins in these complexes are similar in both glial and non-glial extracts, glial cells are enriched in proteins that form a major c complex. Interestingly, the participant proteins in complex c are developmentally regulated during brain development. The possible role of these proteins in increasing local concentrations of Tat in the vicinity of the JCV late RNA start sites is discussed.

The transcription factor E2F-1 modulates TGF-beta1 RNA expression in glial cells.

The cell type specificity of the regulation of expression of the potent growth inhibitory cytokine transforming growth factor-beta (TGF-beta), prompted our analyses of the regulation of TGF-beta1 gene expression in glial cells by viral and cellular oncoproteins. We have shown that SV40 T-antigen diminished TGF-beta1 expression in glial cells and this repression was dependent on the ability of T-antigen to interact with the tumor suppressor protein, pRb, and two structurally related proteins, p107 and p130. The cellular transcription factor E2F-1, which is a downstream effector of T-antigen, was unable to influence expression from the TGF-beta1 promoter by itself. Interestingly, E2F-1 could overcome viral T-antigen-mediated repression of the TGF-beta1 promoter, suggesting potential feedback loop between TGF-beta and E2F in virally transformed glial cells. Using deletion analyses, we have mapped two E2F-1-responsive regions on the TGF-beta1 promoter: a T-antigen-dependent negative regulatory sequence (TdNRS) between -323 and -175, and a T-antigen-independent positive regulatory sequence (TiPRS) between -34 and +10 on the TGF-beta1 promoter. Further examination of TiPRS revealed the presence of a functional E2F binding site. Interestingly, the amino terminus of E2F-1 was required for its activation of TGF-beta1 expression, as mutations in that domain abolished the ability of E2F-1 to increase TGF-beta1 expression. These data suggest that yet-uncharacterized interaction between the amino terminus of E2F-1 and cellular proteins regulates TGF-beta1 expression. The mechanism for E2F-1-mediated T-antigen-dependent regulation of TGF-beta1 expression from TdNRS awaits further characterization.

Association of Pur alpha and E2F-1 suppresses transcriptional activity of E2F-1.

Protein-protein interaction can play an important role in the control of several biological events including gene transcription, replication and cell proliferation. E2F-1 is a DNA-binding transcription factor which, upon interaction with its target DNA sequence, induces expression of several S phase specific genes allowing progression of the cell cycle. Evidently, the activity of this protein is modulated by its cellular partner, pRb, which in the hypophosphorylated form, binds to E2F-1 and inactivates its transcriptional ability. In this study, we have demonstrated that expression of a sequence-specific single-stranded DNA binding protein, Pur alpha, in cells decreases the ability of E2F-1 to exert its transcriptional activity upon the responsive promoter derived from DHFR. Results from band shift experiments revealed that while Pur alpha does not recognize the double-stranded DNA fragment containing the E2F-1 binding site, it has the ability to inhibit E2F-1 interaction with its target DNA sequence. Results from GST pull-down assays and the combined immunoprecipitation/Western blot analysis of nuclear extracts revealed a direct association of E2F-1 with Pur alpha in the absence of the DNA molecule containing the E2F-1 binding site. The association of Pur alpha with E2F-1 may increase the stability of E2F-1, as a higher level of E2F-1 was detected in cells coexpressing Pur alpha and E2F-1. The importance of these observations with respect to the role of Pur alpha in the control of cell cycle progression is discussed.

Purification of a phosphatidylinositol/phosphatidylcholine transfer protein from Neurospora crassa.

This paper reports, for the first time, the purification of a phospholipid transfer protein (PLTP) from a fungus, Neurospora crassa. The protein was purified from the post-microsomal supernatant of N. crassa by successive chromatography on DEAE-cellulose, Sephadex-G75 and PBE 94 (pH 4-7). The purified protein (M(r) 38,000) was found to transfer phosphatidylinositol preferentially over phosphatidylcholine, like the PLTP from the yeast, Saccharomyces cerevisiae. PC transfer was completely inhibited by inactivation of free amino groups or tryptophan residues. Surprisingly, the protein did not cross-react with antibodies against the bovine brain PITP. The cellular content of the protein was maximal during the logarithmic phase of growth. However, no direct correlation between the content of the protein and PC transfer activity could be demonstrated.

Abnormal erythrocyte membrane cytoskeleton structure in chronic myelogenous leukaemia.

Chronic myelogenous leukaemia (CML) is a haematologic malignancy characterised by excessive growth of myeloid cells and their progenitors. Our studies show that there are several abnormalities in CML red blood cells. The proportion of spectrin dimers compared to tetramers extracted from membranes at 4 degrees C, under low ionic strength conditions, increased in CML erythrocytes. These also displayed abnormal thermal sensitivity (between 45 and 46 instead of 49 degrees C). Decreased spectrin tetramer formation observed in several hereditary anaemias has been associated with decreased red cell deformability leading to splenic sequestration. This could also be one of the causes of the severe anaemia observed in CML. Crosslinking with the bifunctional reagent, dimethyl adipimidate (8.6 A) showed significant organizational modification of not only spectrin, but other cytoskeletal components such as ankyrin, bands 4.2 and 5. Enhanced concanavalin A agglutinability of CML erythrocytes also suggests altered topographic distribution of a functionally important membrane protein, band 3.

Abnormalities in erythrocyte membrane band 3 in chronic myelogenous leukemia.

The anion transport activities of erythrocytes from patients with chronic myelogenous leukemia (CML) and normal donors were comparable. In CML erythrocytes, significant reduction in the number of ankyrin-binding sites, present in the cytoplasmic domain of band 3, may lead to partial loss of cytoskeletal anchorage to the bilayer and account for their increased Con-A agglutinability and heat-sensitivity (Basu, J., Kundu, M., Rakshit, M.M. and Chakrabarti, P. (1988) Biochim. Biophys. Acta 945, 121-126).

Purification and characterisation of a non-specific lipid transfer protein from goat liver.

A non-specific lipid transfer protein has been purified from the pH 5.1 supernatant of goat liver by DEAE-cellulose, CM-cellulose and Sephadex G-75 column chromatography. The protein shows a single band on polyacrylamide gel electrophoresis and transfers 450 nmol of phosphatidylcholine per min per mg of protein under the present assay condition. This protein has a subunit molecular weight of 12,000 and an isoelectric point of 8.65. Amino acid analysis reveals the absence of methionine. Histidine has been identified as the only N-terminal amino acid. Besides phosphatidylcholine, the protein transfers phosphatidylinositol, phosphatidylethanolamine, phosphatidylserine and cholesterol. Chemical modification studies showed the involvement of free amino and thiol groups in the maintenance of the transfer activity of the goat liver protein.

Fatty acylation of a 55 kDa membrane protein of human erythrocytes.

The major palmitoylated human erythrocyte membrane protein has an M(r) of 55,000. It is distinct from the glucose transporter and is not derived from band 3 or ankyrin. It resists salt extraction suggesting a high affinity for the membrane. Pulse chase experiments demonstrate that palmitoylation is a dynamic process, and it may therefore have regulatory significance in membrane protein-protein or protein-lipid interaction. Slower dynamics of palmitoylation in erythrocytes from patients suffering from chronic myelogenous leukemia, which are less stable than normal erythrocytes, strengthen this view.