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O6-methylguanine-DNA methyltransferase (MGMT) is an enzyme that removes alkyl groups at the O6-position of guanine in DNA. MGMT expression is reduced or absent in many tumor types derived from a diverse range of tissues, most notably in glioma. Low MGMT expression confers significant sensitivity to DNA alkylating agents such as temozolomide, providing a natural therapeutic index over normal tissue. In this study, we sought to identify novel approaches that could maximally exploit the therapeutic index between tumor cells and normal tissues based on MGMT expression, as a means to enhance selective tumor cell killing. Temozolomide, unlike other alkylators, activated the ataxia telangiectasia and Rad3–related (ATR)–checkpoint kinase 1 (Chk1) axis in a manner that was highly dependent on MGMT status. Temozolomide induced growth delay, DNA double-strand breaks, and G2–M cell-cycle arrest, which led to ATR-dependent phosphorylation of Chk1; this effect was dependent on reduced MGMT expression. Treatment of MGMT-deficient cells with temozolomide increased sensitivity to ATR inhibitors both in vitro and in vivo across numerous tumor cell types. Taken together, this study reveals a novel approach for selectively targeting MGMT-deficient cells with ATR inhibitors and temozolomide. As ATR inhibitors are currently being tested in clinical trials, and temozolomide is a commonly used chemotherapeutic, this approach is clinically actionable. Furthermore, this interaction potently exploits a DNA-repair defect found in many cancers. Significance: Monofunctional alkylating agents sensitize MGMT-deficient tumor cells to ATR inhibitors.

Guayule (Parthenium argentatum A. Gray) is an important domestic source of natural rubber. Commercial field plots are currently established using greenhouse grown seedlings that are hand sown as plugs. However, this practice is expensive and laborious. Direct sowing of guayule seed in the field would reduce time and cost significantly, and yet the effects of seed pelleting, temperature, salinity level, and their interactions on guayule seed germination are not well established. To test germination requirements, non-pelleted (control) and pelleted seeds were planted in solutions having electrical conductivity (EC) of 0, 2, 4, 6, 8, and 10 mS/cm at 10, 20, 30, and 40 °C for 7 days. After 7 days, the non-germinated seeds were transferred to distilled water plates in a 20 °C environment. Seed pelleting, temperature, salinity, and their interactions significantly affected guayule germination. The optimal conditions for seed germination (i.e., highest germination rates) were found to be 20 °C and EC 0–2 mS/cm, regardless of pelleting. Both temperature and salinity delayed germination and decreased viability. Germination was inhibited at both 10 and 40 °C. Salinity effects on seeds decreased as germination temperature became optimal. Lowest germination percentages were observed at EC 6–10 mS/cm and at 30 and 40 °C. Germination percentages increased for treatments after seeds were transferred to optimal conditions. Importantly, pelleted guayule seeds exhibited higher germination than non-pelleted seeds in all treatments. Our results provide important new insights that can help guide the selection of optimal seasonal and soil conditions for field establishment with new direct seeding methods.

Cellulose degradation is essential for the future production of many advanced biofuels. Cellulases from the filamentous fungus Trichoderma reesei are among the most efficient enzymes for the hydrolysis of cellulosic materials. One of the cellulases from T. reesei, cellobiohydrolase II (CBH2), was studied because of its industrial relevance and proven enzymatic activity. Using both crude and rigorous membrane fractionation methods we show that full length T. reesei CBH2 is exclusively localized to the outer membrane when expressed recombinantly in Escherichia coli. Even fusing signal sequence-free maltose-binding protein to the N-terminus of CBH2, which has been shown to increase solubility of other proteins, did not prevent the outer membrane localization of CBH2. These results highlight the difficulties in producing fungal cellulases in bacterial hosts and provide a stepping stone for future cellulase engineering efforts.

Death of the apical shoot and subsequent compensatory growth from previously inhibited axillary buds is a possible result of POST weed control practices. The objective of this research was to determine the efficacy of glyphosate and lactofen on ivyleaf morningglory, common waterhemp, and giant ragweed during mechanically stimulated compensatory growth. Plants were grown in the greenhouse to a height (or lateral growth) of 15 cm; at which time, the apical shoots were removed by cutting just above the cotyledonary node. Plants were allowed to regrow to 15 cm and treated with lactofen or glyphosate. Herbicide treatments were also applied to intact plants that were 15 cm in height for comparison. Weed response to herbicides during mechanically stimulated compensatory growth varied by weed species and herbicide. Giant ragweed under compensatory growth was less sensitive to both glyphosate and lactofen compared with intact plants. Comparison of GR50(the herbicide dose that reduced dry weight by 50%) values indicated that ivyleaf morningglory under compensatory growth was 1.5 times more sensitive to glyphosate than intact plants. Conversely, previously injured ivyleaf morningglory plants were less sensitive to lactofen than intact plants. The GR50for glyphosate applied to intact common waterhemp plants and plants under compensatory growth was similar. However, common waterhemp plants under compensatory growth were more sensitive to lactofen at the three lowest rates evaluated compared with intact plants. In summary, the efficacy of foliar herbicides applied to weeds that exhibit compensatory growth may be different from weeds under a normal growth state.

Field and greenhouse studies were conducted in 2002 and 2003 to evaluate mechanically stimulated compensatory growth response of ivyleaf morningglory, common waterhemp, and giant ragweed. Compensatory growth was initiated by the physical removal of the apical shoot to break apical dominance. The amount of apical shoot removed had an effect on mechanically stimulated compensatory growth of common waterhemp and giant ragweed. With these species, the more of the apical shoot removed from the plant, the less compensatory growth occurred. Removal of the shoot from above the cotyledons resulted in giant ragweed that were 48% shorter and weighed 41% less than control plants at 6 wk after shoot removal. However, the amount of apical shoot removed had no effect on the growth of ivyleaf morningglory compared with control plants at the completion of the study. The influence of plant height at the time of shoot removal on compensatory growth was specific to each weed species. Ivyleaf morningglory exhibited less compensatory growth when the plants were 10 cm at the time of shoot removal compared with 20-, 30-, and 40-cm-tall plants. Removal of the shoot when common waterhemp plants were 30 or 40 cm in height reduced plant weight by 23 and 21%, respectively, compared with control plants. However, no reductions in plant weight were observed when common waterhemp were 10 or 20 cm tall at the time of shoot removal. Giant ragweed subjected to shoot removal was smaller in most growth parameters than control plants, regardless of plant height at the time of shoot removal.

(2002). The Educational-Industrial Complex. The Educational Forum: Vol. 66, No. 4, pp. 302-308.

Ataxia Telangiectasia and Rad3-related (ATR) and Checkpoint kinase 1 (CHK1) stabilize stalled replication forks and prevent their collapse into DNA double strand breaks (DSBs). Inhibition of ATR in cells experiencing oncogenic stress or harboring other cancer-associated defects synergistically increases the formation of DSBs and causes synthetic lethality. Thus specific targeting of ATR represents an emerging strategy to treat a broad spectrum of cancers, most notably those that currently lack effective treatments. We and others have shown that inhibition of the ATR checkpoint kinase is synthetically lethal with multiple distinct cancer-associated mutations, including p53 loss, oncogenic stress (HRAS-G12V, KRAS-G12D, NRAS-G12D, MYC and CCNE1), deficiency in homologous recombination (BRCA1/2, PALB2, ATM loss), alternative lengthening of telomeres (ALT), chromatin modification (SETD2 loss), and others. The specificity of ATR inhibitors is vital to their successful clinical application, since off-targeting increases toxicity to normal cells and limits value in personalized treatments. We report the generation of a novel class of highly potent and specific ATR inhibitors (ATRN series) that exhibit low nanomolar activity in cultured cells (IC50 = 2-8 nM) and do not detectably inhibit ATM, DNA-PK or mTOR (IC50 > 10 µM). In side-by-side comparisons, both the potency and selectivity of the ATRN series is superior to previously reported ATR inhibitors (VE821, VE822, AZD20, AZD6738, ETP-46464). In addition, the ATRN series has sufficient bioavailability and stability for in vivo application. Our lead compound (ATRN-119) slows progression of human BRCA2-deficient PDAC (CAPAN1) and RAS oncogene-driven p53-null colon tumors in mice with minimal toxicity to tissues under normal proliferative control, including the bone marrow and intestine. Additionally, mice engrafted with BRCA2-mutant patient-derived xenograft (PDX) ovarian tumors show a significant reduction in tumor progression after 5 weeks treatment of ATRN-119, and display no toxicity or significant weight loss. In addition, cancers that maintain or reacquire HR function, and thus are resistant to treatment with PARPi or cisplatin, remain responsive to ATRN series inhibitors. Thus, ATRN-119 is highly efficacious in suppressing tumor growth in multiple murine models, including suppression of patient-derived BRCA2-mutant ovarian, and PARP resistant cancers, suggesting that the clinical application of the ATRN series will provide a new and effective treatment for human malignancies with fewer side effects than conventional chemotherapies. In summary, the ATRN series is a highly selective and potent class of ATR inhibitors with therapeutic potential for treating a broad range of cancers. The potentially identified biomarkers, in particular HR-deficiency, will inform patient selection (a critical component for delivering medical benefit) for treatment with our agent and could reduce future clinical risk and side-effects. Thus targeting patients with HR-deficient cancers is a particularly promising strategy in treating a broad range of cancers. Citation Format: Laura R. Butler, Ryan L. Ragland, Hank J. Breslin, Erin George, Tina Gill, Matthew Scheiwer, Nicolas Gordon, Karen Knudsen, Fiona Simpkins, Oren Gilad and Eric J. Brown. Potent and selective ATR inhibitors for the treatment of homologous-recombination deficient and PARPi-resistant cancers [abstract]. In: Proceedings of the AACR Special Conference on DNA Repair: Tumor Development and Therapeutic Response; 2016 Nov 2-5; Montreal, QC, Canada. Philadelphia (PA): AACR; Mol Cancer Res 2017;15(4_Suppl):Abstract nr A16.

In this paper we demonstrate a technique for extracting 3-dimensional data from 2-dimensional GPS-tagged video. We call our method Minimum Separation Vector Mapping (MSVM), and we verify it's performance versus traditional Structure From Motion (SFM) techniques in the field of GPS-tagged aerial imagery, including GPS-tagged full motion video (FMV). We explain how MSVM is better posed to natively exploit the a priori content of GPS tags when compared to SFM. We show that given GPS-tagged images and moderately well known intrinsic camera parameters, our MSVM technique consistently outperforms traditional SFM implementations under a variety of conditions.

The study of violent crime is rooted in several hundred years of theological, biological, sociological, and psychological theories. Explanations for such behaviors range from persons being possessed by evil spirits to an abnormality in the brain's prefrontal cortex. In contrast, research into white-collar criminality is a relatively new endeavor—scarcely more than 70 years old. It is grounded in the work of Edwin Sutherland and those he directly influenced, including Donald Cressey and Marshall Clinard. Keywords: black markets; Bush, George W.; corporate fraud; corruption; embezzlement; Enron; Lay, Ken; occupational crime; public corruption; Sutherland, Edwin; white-collar crime

Two cases of hemorrhagic meningoencephalitis secondary to Naegleria fowleri infection confirmed by postmortem analysis are described. The first patient is a 5-year-old boy who presented with a severe headache, neck stiffness, and lethargy. His neurologic examination was significant for somnolence and nuchal rigidity. Cerebrospinal fluid studies and structural neuroimaging were consistent with hemorrhagic meningoencephalitis. Another 5-year-old boy presented to a different institution 2 miles away in the same week with similar complaints. Both patients declined rapidly and expired within 48 hours of admission secondary to transtentorial herniation caused by the mass effect of inflammation, edema, and hemorrhage with displacement of the brain stem. Histopathologic and immunochemistry analysis of brain tissue revealed the presence of Naegleria trophozoites in both cases.

Ataxia Telangiectasia and Rad3-related (ATR) and Checkpoint kinase 1 (CHK1) stabilize stalled replication forks and prevent their collapse into DNA double strand breaks (DSBs). Inhibition of ATR in cells experiencing oncogenic stress or harboring other cancer-associated defects synergistically increases the formation of DSBs and causes synthetic lethality. Thus specific targeting of ATR represents an emerging strategy to treat a broad spectrum of cancers, most notably those that currently lack effective treatments. Atrin Pharmaceuticals has synthesized a novel series of small molecules that inhibit ATR at low nanomolar concentrations in cultured cells. These compounds have the highest known potency for inhibiting ATR and maintain >800-fold lower cellular activity towards other kinases of the same family (ATM, DNA-PKcs and mTOR), which are substantially off-targeted by previously reported ATR inhibitors. Atrin's lead compound (ATRN-119), as a single agent, selectively kills cancer cells subjected to oncogenic stress, alternative lengthening of telomeres (ALT) or loss of double strand break (DSB) homologous recombination repair mechanism (BRCA1 or BRCA2 deficiency). Furthermore, ATRN-119 cytotoxicity is synergistically enhanced when combined with conventional chemotherapeutics, such as etoposide, cisplatin and olaparib. Therefore, this inhibitor can be used in combination with other therapeutics to potentiate its anti-tumor activity. In vivo studies of RAS oncogene driven HCT116 p53-null flank tumors in mice demonstrate the ability of our lead compound to slow tumor progression, with minimal toxicity to tissues under normal proliferative control, including the bone marrow and intestine. Additionally, mice engrafted with BRCA2-mutant patient-derived ovarian tumors show a significant reduction in progression after 5 weeks treatment (100 mg/kg BID) of ATRN-119, and display no toxicity or significant weight loss. Thus, ATRN-119 is highly efficacious in suppressing tumor growth in multiple murine models, including suppression of patient-derived BRCA2-mutant ovarian cancer, suggesting that the clinical application of the ATRN series will provide a new and effective treatment for human malignancies with fewer side effects than conventional chemotherapies. Citation Format: Laura R. Butler, Ryan L. Ragland, Hank J. Breslin, Tina Gill, Erin George, Fiona Simpkins, Eric J. Brown, Oren Gilad. Highly specific ATR inhibitors as a therapeutic approach for a broad spectrum of cancers. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1226.