Outcomes of a Modified CALGB 19802 Regimen in Adult Acute Lymphoblastic Leukemia

We analyzed the efficacy and toxicity of a modified Cancer and Leukemia Group B (CALGB) 19802 regimen in adult acute lymphoblastic leukemia (ALL). From February 2002 to August 2005, 25 adults with untreated ALL were enrolled in the study. Compared to the original regimen, the modified CALGB 19802 regimen consisted of a 4-drug induction (cyclophosphamide, daunorubicin, vincristine, and prednisone) instead of a 5-drug induction (L-asparaginase was added to the previous regimen). This was followed by high-dose methotrexate (1,000 mg/m2×3 days) and cytarabine (2,000 mg/m2×4 days) for the consolidation cycles. High-dose systemic and intrathecal methotrexate was given for central nervous system prophylaxis. Twenty-three patients (92%) achieved a complete remission (CR), and two patients (8%) had refractory disease. With a median follow-up of 21.5 months, 10 patients (40%) were alive and continued to be in CR. The 3-yr probability of an event-free survival and the overall survival were 39.0% and 47.4%, respectively. Treatment related mortality and major grade 3 to 4 neurotoxicity occurred in 1 patient and 3 patients, respectively. The modified CALGB 19802 regimen demonstrated a high remission rate and a favorable survival rate

Mechanisms underlying the role of Drosophila timeless in the molecular clock and in the circadian response to light

Despite major advances in circadian biology, we still do not understand how the clock is sustained and how it generates a 24-hour oscillation. In Drosophila melanogaster, circadian rhythms are driven by a negative feedback loop that includes the key regulators, period ( per) and timeless (tim). A critical step in this molecular cycle is the timed nuclear localization of PER/TIM, but the mechanisms underlying this are not known. In addition, while entrainment of the molecular cycle to light is known to require light-induced degradation of TIM, how this event resets the clock is not understood. In this thesis, we identified specific components that mediate the nuclear translocation of clock proteins and also report that a specific residue in TIM regulates its light-induced degradation. We show that a specific Importin, importin &agr;1, targets TIM as a cargo, rather than the major timekeeper PER, and TIM in turn acts like a karyopherin to co-transport PER into the nucleus. Other components of the importin pathway (e.g. RAN-GTP and nuclear pore protein NUP153) are also shown to be required for nuclear entry of PER and TIM. Taken together, we report a unique twist to the known nuclear import pathway, in that a cargo (TIM) serves as an adaptor to transport another cargo (PER), and identify new components required for clock function. In our work on light-dependent regulation of TIM, we found that a specific tyrosine residue (Y48) on TIM is required for robust TIM degradation by light. Mutation of the Y48 residue on TIM has even more profound effects on light-induced modification of PER and on circadian behavioral activity of flies. These findings suggest that prior to its degradation TIM transmits photic signals to PER. These studies are expected to contribute to an understanding of how a circadian clock is generated and sustained, which is a long-debated but yet unsolved question

Mechanisms underlying the role of Drosophila timeless in the molecular clock and in the circadian response to light

Despite major advances in circadian biology, we still do not understand how the clock is sustained and how it generates a 24-hour oscillation. In Drosophila melanogaster, circadian rhythms are driven by a negative feedback loop that includes the key regulators, period ( per) and timeless (tim). A critical step in this molecular cycle is the timed nuclear localization of PER/TIM, but the mechanisms underlying this are not known. In addition, while entrainment of the molecular cycle to light is known to require light-induced degradation of TIM, how this event resets the clock is not understood. In this thesis, we identified specific components that mediate the nuclear translocation of clock proteins and also report that a specific residue in TIM regulates its light-induced degradation. We show that a specific Importin, importin &agr;1, targets TIM as a cargo, rather than the major timekeeper PER, and TIM in turn acts like a karyopherin to co-transport PER into the nucleus. Other components of the importin pathway (e.g. RAN-GTP and nuclear pore protein NUP153) are also shown to be required for nuclear entry of PER and TIM. Taken together, we report a unique twist to the known nuclear import pathway, in that a cargo (TIM) serves as an adaptor to transport another cargo (PER), and identify new components required for clock function. In our work on light-dependent regulation of TIM, we found that a specific tyrosine residue (Y48) on TIM is required for robust TIM degradation by light. Mutation of the Y48 residue on TIM has even more profound effects on light-induced modification of PER and on circadian behavioral activity of flies. These findings suggest that prior to its degradation TIM transmits photic signals to PER. These studies are expected to contribute to an understanding of how a circadian clock is generated and sustained, which is a long-debated but yet unsolved question

Optimization of ultrasound-assisted extraction of glycyrrhizic acid from licorice using response surface methodology

Background: The present study optimized ultrasound-assisted extraction conditions to maximize extraction yields of glycyrrhizic acid from licorice. Methods: The optimal extraction temperature (X1), extraction time (X2), and methanol concentration (X3) were identified using response surface methodology (RSM). A central composite design (CCD) was used for experimental design and analysis of the results to obtain the optimal processing parameters. Results: Statistical analyses revealed that three variables and the quadratic of X1, X2, and X3 had significant effects on the yields and were followed by significant interaction effects between the variables of X2 and X3 (p < 0.01). A 3D response surface plot and contour plots derived from the mathematical models were applied to determine the optimal conditions. The optimum ultrasound-assisted extraction conditions were as follows: extraction temperature, 69 °C; extraction time, 34 min; and methanol concentration, 57%. Under these conditions, the experimental yield of glycyrrhizic acid was 3.414%, which agreed closely with the predicted value (3.406%). Conclusion: The experimental values agreed with those predicted by RSM models, thus indicating the suitability of the model employed and the success of RSM in optimizing the extraction conditions. Keywords: licorice, glycyrrhizic acid, ultrasound-assisted extraction, optimization, response surface methodolog

Tuning polarity and improving charge transport in organic semiconductors

Although state-of-the-art ambipolar polymer semiconductors have been extensively reported in recent years, high-performance ambipolar polymers with tunable dominant polarity are still required to realize on-demand, target-specific, high-performance organic circuitry. Herein, dithienyl-diketopyrrolopyrrole (TDPP)-based polymer semiconductors with engineered side-chains have been synthesized, characterized and employed in ambipolar organic field-effect transistors, in order to achieve controllable and improved electrical properties. Thermally removable tert-butoxycarbonyl (t-BOC) groups and hybrid siloxane-solubilizing groups are introduced as the solubilizing groups, and they are found to enable the tunable dominant polarity and the enhanced ambipolar performance, respectively. Such outstanding performance based on our molecular design strategies makes these ambipolar polymer semiconductors highly promising for low-cost, large-area, and flexible electronics.110sciescopu

<i>Drosophila</i> TIM Binds Importin α1, and Acts as an Adapter to Transport PER to the Nucleus

<div><p>Regulated nuclear entry of clock proteins is a conserved feature of eukaryotic circadian clocks and serves to separate the phase of mRNA activation from mRNA repression in the molecular feedback loop. In <i>Drosophila</i>, nuclear entry of the clock proteins, PERIOD (PER) and TIMELESS (TIM), is tightly controlled, and impairments of this process produce profound behavioral phenotypes. We report here that nuclear entry of PER-TIM in clock cells, and consequently behavioral rhythms, require a specific member of a classic nuclear import pathway, Importin α1 (IMPα1). In addition to IMPα1, rhythmic behavior and nuclear expression of PER-TIM require a specific nuclear pore protein, Nup153, and Ran-GTPase. IMPα1 can also drive rapid and efficient nuclear expression of TIM and PER in cultured cells, although the effect on PER is mediated by TIM. Mapping of interaction domains between IMPα1 and TIM/PER suggests that TIM is the primary cargo for the importin machinery. This is supported by attenuated interaction of IMPα1 with TIM carrying a mutation previously shown to prevent nuclear entry of TIM and PER. TIM is detected at the nuclear envelope, and computational modeling suggests that it contains HEAT-ARM repeats typically found in karyopherins, consistent with its role as a co-transporter for PER. These findings suggest that although PER is the major timekeeper of the clock, TIM is the primary target of nuclear import mechanisms. Thus, the circadian clock uses specific components of the importin pathway with a novel twist in that TIM serves a karyopherin-like role for PER.</p></div

Highly Efficient Photoelectrochemical Hydrogen Production Using Nontoxic CuIn1.5Se3 Quantum Dots with ZnS/SiO2 Double Overlayers

Quantum dots (QDs) are a promising material for photoelectrochemical (PEC) hydrogen (H-2) production because of their attractive optical properties including high optical absorption coefficient, band-gap tunability, and potential multiple exciton generation. To date, QDs containing toxic elements such as Cd or Pb have been mainly investigated for PEC H-2 production, which cannot be utilized in practice because of the environmental issue. Here, we demonstrate a highly efficient type II heterojunction photoanode of nontoxic CuIn1.5Se3 (CISe) QDs and a mesoporous TiO2 film. In addition, ZnS/SiO2 double overlayers are deposited on the photoanodes to passivate surface defect sites on the CISe QDs, leading to the enhancement of both photocurrent density and photostability. Due to a combination of a wide light absorption range of the CISe QDs and the reduced interfacial charge recombination by the overlayers, a remarkable photocurrent density of 8.5 mA cm(-2) (at 0.5 VRHE) is obtained under 1 sun illumination, which is a record for the PEC sulfite oxidation based on nontoxic QD photoanodes

TIM is primary cargo for IMPα1.

<p>(A) S2 cells were transiently transfected with pIZ-<i>tim</i>-V5 (wt), pIZ-<i>tim</i>_mNLS-V5 (<i>tim</i> carrying a mutant NLS), pIZ-<i>imp_α1</i>-VSV, or pIZ-<i>imp_α1</i>∆IBB-VSV as indicated. After 60 hours, cell lysates were immunoprecipitated with an anti-VSV antibody (against IMPα1 or IMPα1IBB) and detected with an anti-V5 antibody. Similar results were obtained in three independent experiments. (B) S2 cells were transiently transfected with pIZ-<i>tim</i>-V5, pAc-<i>per</i>-HA, pIZ-<i>imp_α1</i>-VSV, or pIZ-<i>imp_α1</i>∆IBB-VSV as indicated. After 60 hours, cell lysates were immunoprecipitated with an anti-HA antibody (against PER) and detected with an anti-V5 antibody or with an anti-VSV. Similar results were obtained in three independent experiments. IMPα1 co-immunoprecipitated with PER is indicated with an asterisk. (C) S2 cells were transfected with pIZ-<i>tim</i>-V5 (wt), pIZ-<i>tim</i>^PL-V5, or pIZ-<i>tim</i>^TA-V5 in the presence or absence of pIZ-<i>imp_α1</i>∆IBB-VSV as indicated. After 60 hours, cells were subjected to IP using an anti-VSV antibody (against empty vector or IMPα1∆IBB) and detected with an anti-V5 antibody. Similar results were obtained in three independent experiments. The quantification of interaction between IMPα1 and TIM^WT/PL/TA is shown in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004974#pgen.1004974.s009" target="_blank">S9 Fig.</a></p

Effects of downregulating importin α genes on free-running circadian locomotor rhythms.

<p>^a Flies with FFT value > 0.01 are counted as a rhythmic.</p><p>^b P < 0.005 compared to both α1 RNAi-1/+; dicer/+ and Pdf-GAL4/+; dicer/+ controls, by Student's t-test.</p><p>^c These flies showed arrhythmicity or weak rhythmicity 4–5 days after transferring to DD. Periods and FFTs during first 4–5 days in DD are shown.</p><p>^d P < 0.01 compared to both α3 RNAi-1/dicer and TUG/+; dicer/+ controls, by Student's t-test</p><p>Effects of downregulating importin α genes on free-running circadian locomotor rhythms.</p

Molecular oscillations of PER and TIM are dampened in Df(3L)α1S1 flies.

<p>(A) Quantitive PCR (qPCR) reveals that <i>per</i> and <i>tim</i> mRNA oscillations are blunted in Df(3L)α1S1 flies relative to those in wild-type flies. <i>importin α1</i> mRNA levels do not cycle. <i>actin</i> was used as an internal control to normalize transcript levels. The quantification curves in each panel were plotted as average ± standard error of the mean (SEM) of three independent experiments. (B and C) Western blots of adult fly heads of wild-type (iso³¹), heterozygous, and homozygous Df(3L)α1S1 flies were probed for PER and TIM. Flies of the indicated genotypes were collected (B) at different zeitgeber times (ZT) on the 3^rd day of LD (LD3) and (C) at different circadian times (CT) on the 1^st day of DD (DD1). The blots were also probed with antibody to Hsp70 as a loading control. Similar results were obtained in two or three independent experiments. The quantification of TIM expression levels is shown in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004974#pgen.1004974.s005" target="_blank">S5 Fig.</a></p