bluuebunny/crossref_metadata_2025_split huggingface dataset:
Critical Contribution of Tyr15 in the HIV-1 Integrase (IN) in Facilitating IN Assembly and Nonenzymatic Function through the IN Precursor Form with Reverse Transcriptase
Authors: Takahata Tatsuro , Takeda Eri , Tobiume Minoru , Tokunaga Kenzo , Yokoyama Masaru , Huang Yu-Lun , Hasegawa Atsuhiko , Shioda Tatsuo , Sato Hironori , Kannagi Mari , Masuda Takao 
Published: October 2016

ABSTRACT

Nonenzymatic roles for HIV-1 integrase (IN) at steps prior to the enzymatic integration step have been reported. To obtain structural and functional insights into the nonenzymatic roles of IN, we performed genetic analyses of HIV-1 IN, focusing on a highly conserved Tyr15 in the N-terminal domain (NTD), which has previously been shown to regulate an equilibrium state between two NTD dimer conformations. Replacement of Tyr15 with alanine, histidine, or tryptophan prevented HIV-1 infection and caused severe impairment of reverse transcription without apparent defects in reverse transcriptase (RT) or in capsid disassembly kinetics after entry into cells. Cross-link analyses of recombinant IN proteins demonstrated that lethal mutations of Tyr15 severely impaired IN structure for assembly. Notably, replacement of Tyr15 with phenylalanine was tolerated for all IN functions, demonstrating that a benzene ring of the aromatic side chain is a key moiety for IN assembly and functions. Additional mutagenic analyses based on previously proposed tetramer models for IN assembly suggested a key role of Tyr15 in facilitating the hydrophobic interaction among IN subunits, together with other proximal residues within the subunit interface. A rescue experiment with a mutated HIV-1 with RT and IN deleted (ΔRT ΔIN) and IN and RT supplied in
trans
revealed that the nonenzymatic IN function might be exerted through the IN precursor conjugated with RT (RT-IN). Importantly, the lethal mutations of Tyr15 significantly reduced the RT-IN function and assembly. Taken together, Tyr15 seems to play a key role in facilitating the proper assembly of IN and RT on viral RNA through the RT-IN precursor form.

IMPORTANCE
Inhibitors of the IN enzymatic strand transfer function (INSTI) have been applied in combination antiretroviral therapies to treat HIV-1-infected patients. Recently, allosteric IN inhibitors (ALLINIs) that interact with HIV-1 IN residues, the locations of which are distinct from the catalytic sites targeted by INSTI, have been discovered. Importantly, ALLINIs affect the nonenzymatic role(s) of HIV-1 IN, providing a rationale for the development of next-generation IN inhibitors with a mechanism that is distinct from that of INSTI. Here, we demonstrate that Tyr15 in the HIV-1 IN NTD plays a critical role during IN assembly by facilitating the hydrophobic interaction of the NTD with the other domains of IN. Importantly, we found that the functional assembly of IN through its fusion form with RT is critical for IN to exert its nonenzymatic function. Our results provide a novel mechanistic insight into the nonenzymatic function of HIV-1 IN and its prevention.
Myeloid Cell Origins, Differentiation, and Clinical Implications
Authors: Weiskopf Kipp , Schnorr Peter J. , Pang Wendy W. , Chao Mark P. , Chhabra Akanksha , Seita Jun , Feng Mingye , Weissman Irving L. 
Published: October 2016

ABSTRACTThe hematopoietic stem cell (HSC) is a multipotent stem cell that resides in the bone marrow and has the ability to form all of the cells of the blood and immune system. Since its first purification in 1988, additional studies have refined the phenotype and functionality of HSCs and characterized all of their downstream progeny. The hematopoietic lineage is divided into two main branches: the myeloid and lymphoid arms. The myeloid arm is characterized by the common myeloid progenitor and all of its resulting cell types. The stages of hematopoiesis have been defined in both mice and humans. During embryological development, the earliest hematopoiesis takes place in yolk sac blood islands and then migrates to the fetal liver and hematopoietic organs. Some adult myeloid populations develop directly from yolk sac progenitors without apparent bone marrow intermediates, such as tissue-resident macrophages. Hematopoiesis also changes over time, with a bias of the dominating HSCs toward myeloid development as animals age. Defects in myelopoiesis contribute to many hematologic disorders, and some of these can be overcome with therapies that target the aberrant stage of development. Furthermore, insights into myeloid development have informed us of mechanisms of programmed cell removal. The CD47/SIRPα axis, a myeloid-specific immune checkpoint, limits macrophage removal of HSCs but can be exploited by hematologic and solid malignancies. Therapeutics targeting CD47 represent a new strategy for treating cancer. Overall, an understanding of hematopoiesis and myeloid cell development has implications for regenerative medicine, hematopoietic cell transplantation, malignancy, and many other diseases.
Tuberculosis Diagnostics: State of the Art and Future Directions
Authors: Pai Madhukar , Nicol Mark P. , Boehme Catharina C. 
Published: October 2016

ABSTRACT
Rapid and accurate diagnosis is critical for timely initiation of anti-tuberculosis (TB) treatment, but many people with TB (or TB symptoms) do not have access to adequate initial diagnosis. In many countries, TB diagnosis is still reliant on sputum microscopy, a test with known limitations. However, new diagnostics are starting to change the landscape. Stimulated, in part, by the success and rollout of Xpert MTB/RIF, an automated, molecular test, there is now considerable interest in new technologies. The landscape looks promising with a pipeline of new tools, particularly molecular diagnostics, and well over 50 companies actively engaged in product development, and many tests have been reviewed by WHO for policy endorsement. However, new diagnostics are yet to reach scale, and there needs to be greater convergence between diagnostics development and the development of shorter TB drug regimens. Another concern is the relative absence of non-sputum-based diagnostics in the pipeline for children, and of biomarker tests for triage, cure, and latent TB progression. Increased investments are necessary to support biomarker discovery, validation, and translation into clinical tools. While transformative tools are being developed, high-burden countries will need to improve the efficiency of their health care delivery systems, ensure better uptake of new technologies, and achieve greater linkages across the TB and HIV care continuum. While we wait for next-generation technologies, national TB programs must scale up the best diagnostics currently available, and use implementation science to get the maximum impact.
Intermittent hypobaric hypoxia combined with aerobic exercise improves muscle morphofunctional recovery after eccentric exercise to exhaustion in trained rats
Authors: Rizo-Roca D. , Ríos-Kristjánsson J. G. , Núñez-Espinosa C. , Santos-Alves E. , Gonçalves I. O. , Magalhães J. , Ascensão A. , Pagès T. , Viscor G. , Torrella J. R. 
Published: October 2016

Unaccustomed eccentric exercise leads to muscle morphological and functional alterations, including microvasculature damage, the repair of which is modulated by hypoxia. We present the effects of intermittent hypobaric hypoxia and exercise on recovery from eccentric exercise-induced muscle damage (EEIMD). Soleus muscles from trained rats were excised before (CTRL) and 1, 3, 7, and 14 days after a double session of EEIMD protocol. A recovery treatment consisting of one of the following protocols was applied 1 day after the EEIMD: passive normobaric recovery (PNR), a 4-h daily exposure to passive hypobaric hypoxia at 4,000 m (PHR), or hypobaric hypoxia exposure followed by aerobic exercise (AHR). EEIMD produced an increase in the percentage of abnormal fibers compared with CTRL, and it affected the microvasculature by decreasing capillary density (CD, capillaries per mm2) and the capillary-to-fiber ratio (CF). After 14 days, AHR exhibited CD and CF values similar to those of CTRL animals (789 and 3.30 vs. 746 and 3.06) and significantly higher than PNR (575 and 2.62) and PHR (630 and 2.92). Furthermore, VEGF expression showed a significant 43% increase in AHR when compared with PNR. Moreover, after 14 days, the muscle fibers in AHR had a more oxidative phenotype than the other groups, with significantly smaller cross-sectional areas (AHR, 3,745; PNR, 4,502; and PHR, 4,790 µm2), higher citrate synthase activity (AHR, 14.8; PNR, 13.1; and PHR, 12 µmol·min−1·mg−1) and a significant 27% increment in PGC-1α levels compared with PNR. Our data show that hypoxia combined with exercise attenuates or reverses the morphofunctional alterations induced by EEIMD. NEW & NOTEWORTHY Our study provides new insights into the use of intermittent hypobaric hypoxia combined with exercise as a strategy to recover muscle damage induced by eccentric exercise. We analyzed the effects of hypobaric exposure combined with aerobic exercise on histopathological features of muscle damage, fiber morphofunctionality, capillarization, angiogenesis, and the oxidative capacity of damaged soleus muscle. Most of these parameters were improved after a 2-wk protocol of intermittent hypobaric hypoxia combined with aerobic exercise.
Dysregulation of RUNX2/Activin-A Axis upon miR-376c Downregulation Promotes Lymph Node Metastasis in Head and Neck Squamous Cell Carcinoma
Authors: Chang Wei-Min , Lin Yuan-Feng , Su Chia-Yi , Peng Hsuan-Yu , Chang Yu-Chan , Lai Tsung-Ching , Wu Guan-Hsun , Hsu Yuan-Ming , Chi Li-Hsing , Hsiao Jenn-Ren , Chen Chi-Long , Chang Jang-Yang , Shieh Yi-Shing , Hsiao Michael , Shiah Shine-Gwo 
Published: October 2016

Abstract
Epigenetic correlates of the head and neck cancer may illuminate its pathogenic roots. Through a gene set enrichment analysis, we found that the oncogenic transcription factor RUNX2 is widely upregulated in the head and neck squamous cell carcinoma (HNSCC) with lymph node metastasis, where it also predicts poor prognosis in patients with HNSCC. Enforced expression of ectopic RUNX2 promoted the metastatic capabilities of HNSCC, whereas RUNX2 silencing inhibited these features. Mechanistic investigations showed that manipulating levels of activin A (INHBA) could rescue or compromise the RUNX2-mediated metastatic capabilities of HNSCC cells. Furthermore, we found that miR-376c-3p encoded within the 3′-untranslated region of RUNX2 played a pivotal role in regulating RUNX2 expression in highly metastatic HNSCC cells, where it was downregulated commonly. Restoring miR-376c expression in this setting suppressed expression of RUNX2/INHBA axis along with metastatic capability. Clinically, we observed an inverse relationship between miR-376c-3p expression and the RUNX2/INHBA axis in HNSCC specimens. In summary, our results defined a novel pathway in which dysregulation of the RUNX2/INHBA axis due to miR-376c downregulation fosters lymph node metastasis in HNSCC. Cancer Res; 76(24); 7140–50. ©2016 AACR.
Determinants of Light and Intermittent Smoking in the United States: Results from Three Pooled National Health Surveys
Authors: Reyes-Guzman Carolyn M. , Pfeiffer Ruth M. , Lubin Jay , Freedman Neal D. , Cleary Sean D. , Levine Paul H. , Caporaso Neil E. 
Published: October 2016

Abstract
Background: Light and/or intermittent smokers have been the fastest growing segment of cigarette smokers in the United States over the past two decades. Defining their behavioral characteristics is a critical public health priority.
Methods: Our sample included 78,229 U.S. adults from three pooled contemporary population-based surveys: the 2012 NHIS, 2012 NSDUH, and 2011–2012 NHANES. We classified current smokers into four categories (light and intermittent [LITS], light-daily, heavier-intermittent, and heavier-daily) and assessed smoking behaviors, illicit drug use, and mental health indicators using weighted analyses.
Results: Analyses associated smoking categories with nicotine dependence, age of smoking initiation, race/ethnicity, and other demographic and behavioral factors. Compared with heavier-daily smokers, smokers who were LITS were most likely to have mild or no nicotine dependence (weighted odds ratio [OR], 16.92; 95% confidence interval [CI], 13.10–21.85), to start smoking cigarettes regularly after age 21 (OR, 3.42; 95% CI, 2.84–4.12), and to be Hispanic (OR, 5.38; 95% CI, 4.38–6.61). Additional significant results were found for other categories of smokers.
Conclusions: Based on pooled data from three large national surveys, light and/or intermittent smokers differed in smoking, drug use, and mental health behaviors from heavier-daily, former, and never smokers. Notable differences by level of smoking frequency and intensity were observed for nicotine dependence, age of smoking initiation, and race/ethnicity.
Impact: Our results may help focus preventive measures and policies for the growing number of light and/or intermittent smokers in the United States because smoking patterns vary by behavioral and socioeconomic factors. Cancer Epidemiol Biomarkers Prev; 26(2); 228–39. ©2016 AACR.
Inhibition of STAT3 with the Generation 2.5 Antisense Oligonucleotide, AZD9150, Decreases Neuroblastoma Tumorigenicity and Increases Chemosensitivity
Authors: Odate Seiichi , Veschi Veronica , Yan Shuang , Lam Norris , Woessner Richard , Thiele Carol J. 
Published: October 2016

Abstract
Purpose: Neuroblastoma is a pediatric tumor of peripheral sympathoadrenal neuroblasts. The long-term event-free survival of children with high-risk neuroblastoma is still poor despite the improvements with current multimodality treatment protocols. Activated JAK/STAT3 pathway plays an important role in many human cancers, suggesting that targeting STAT3 is a promising strategy for treating high-risk neuroblastoma.
Experimental Design: To evaluate the biologic consequences of specific targeting of STAT3 in neuroblastoma, we assessed the effect of tetracycline (Tet)-inducible STAT3 shRNA and the generation 2.5 antisense oligonucleotide AZD9150 which targets STAT3 in three representative neuroblastoma cell line models (AS, NGP, and IMR32).
Results: Our data indicated that Tet-inducible STAT3 shRNA and AZD9150 inhibited endogenous STAT3 and STAT3 target genes. Tet-inducible STAT3 shRNA and AZD9150 decreased cell growth and tumorigenicity. In vivo, STAT3 inhibition by Tet-inducible STAT3 shRNA or AZD9150 alone had little effect on growth of established tumors. However, when treated xenograft tumor cells were reimplanted into mice, there was a significant decrease in secondary tumors in the mice receiving AZD9150-treated tumor cells compared with the mice receiving ntASO-treated tumor cells. This indicates that inhibition of STAT3 decreases the tumor-initiating potential of neuroblastoma cells. Furthermore, inhibition of STAT3 significantly increased neuroblastoma cell sensitivity to cisplatin and decreased tumor growth and increased the survival of tumor-bearing mice in vivo.
Conclusions: Our study supports the development of strategies targeting STAT3 inhibition in combination with conventional chemotherapy for patients with high-risk neuroblastoma. Clin Cancer Res; 23(7); 1771–84. ©2016 AACR.
Integrative Systemic and Local Metabolomics with Impact on Survival in High-Grade Serous Ovarian Cancer
Authors: Bachmayr-Heyda Anna , Aust Stefanie , Auer Katharina , Meier Samuel M. , Schmetterer Klaus G. , Dekan Sabine , Gerner Christopher , Pils Dietmar 
Published: October 2016

Abstract
Purpose: Cancer metabolism is characterized by alterations including aerobic glycolysis, oxidative phosphorylation, and need of fuels and building blocks.
Experimental Design: Targeted metabolomics of preoperative and follow-up sera, ascites, and tumor tissues, RNA sequencing of isolated tumor cells, local and systemic chemokine, and local immune cell infiltration data from up to 65 high-grade serous ovarian cancer patients and 62 healthy controls were correlated to overall survival and integrated in a Systems Medicine manner.
Results: Forty-three mainly (poly)unsaturated glycerophospholipids and four essential amino acids (citrulline) were significantly reduced in patients with short compared with long survival and healthy controls. The glycerophospholipid fingerprint is identical to the fingerprint from isolated (very) low-density lipoproteins (vLDL), indicating that the source of glycerophospholipids consumed by tumors is (v)LDL. A glycerophospholipid-score (HR, 0.46; P = 0.007) and a 100-gene signature (HR, 0.65; P = 0.004) confirmed the independent impact on survival in training (n = 65) and validation (n = 165) cohorts. High concentrations of LDLs and glycerophospholipids were independently predictors for favorable survival. Patients with low glycerophospholipids presented with more systemic inflammation (C-reactive protein and fibrinogen negatively and albumin positively correlated) but less adaptive immune cell tumor infiltration (lower tumor and immune cell PD-L1 expression), less oxygenic respiration and increased triglyceride biosynthesis in tumor cells, and lower histone expressions, correlating with higher numbers of expressed genes and more transcriptional noise, a putative neo-pluripotent tumor cell phenotype.
Conclusions: Low serum phospholipids and essential amino acids are correlated with worse outcome in ovarian cancer, accompanied by a specific tumor cell phenotype. Clin Cancer Res; 23(8); 2081–92. ©2016 AACR.
6α-Acetoxyanopterine: A Novel Structure Class of Mitotic Inhibitor Disrupting Microtubule Dynamics in Prostate Cancer Cells
Authors: Levrier Claire , Sadowski Martin C. , Rockstroh Anja , Gabrielli Brian , Kavallaris Maria , Lehman Melanie , Davis Rohan A. , Nelson Colleen C. 
Published: October 2016

Abstract
The lack of a cure for metastatic castrate-resistant prostate cancer (mCRPC) highlights the urgent need for more efficient drugs to fight this disease. Here, we report the mechanism of action of the natural product 6α-acetoxyanopterine (6-AA) in prostate cancer cells. At low nanomolar doses, this potent cytotoxic alkaloid from the Australian endemic tree Anopterus macleayanus induced a strong accumulation of LNCaP and PC-3 (prostate cancer) cells as well as HeLa (cervical cancer) cells in mitosis, severe mitotic spindle defects, and asymmetric cell divisions, ultimately leading to mitotic catastrophe accompanied by cell death through apoptosis. DNA microarray of 6-AA–treated LNCaP cells combined with pathway analysis identified very similar transcriptional changes when compared with the anticancer drug vinblastine, which included pathways involved in mitosis, microtubule spindle organization, and microtubule binding. Like vinblastine, 6-AA inhibited microtubule polymerization in a cell-free system and reduced cellular microtubule polymer mass. Yet, microtubule alterations that are associated with resistance to microtubule-destabilizing drugs like vinca alkaloids (vinblastine/vincristine) or 2-methoxyestradiol did not confer resistance to 6-AA, suggesting a different mechanism of microtubule interaction. 6-AA is a first-in-class microtubule inhibitor that features the unique anopterine scaffold. This study provides a strong rationale to further develop this novel structure class of microtubule inhibitor for the treatment of malignant disease. Mol Cancer Ther; 16(1); 3–15. ©2016 AACR.
The MAP kinase JNK2 mediates cigarette smoke-induced arterial thrombosis
Authors: Stämpfli Simon F. , Reiner Martin F. , Shi Yi , Keller Stephan , Akhmedov Alexander , Clerigué Ariane Schaub , Spescha Remo D. , Beer Hans-Jürg , Lüscher Thomas F. , Tanner Felix C. , Camici Giovanni G. , Breitenstein Alexander 
Published: October 2016

SummaryDespite public awareness of its deleterious effects, smoking remains a major cause of death. Indeed, it is a risk factor for atherothrombotic complications and in line with this, the introduction of smoking ban in public areas reduced smoking-associated cardiovascular complications. Nonetheless, smoking remains a major concern, and molecular mechanisms by which it causes cardiovascular disease are not known. Peripheral blood monocytes from healthy smokers displayed increased JNK2 and tissue factor (TF) gene expression compared to non-smokers (n=15, p<0.05). Similarly, human aortic endothelial cells exposed to cigarette smoke total particulate matter (CS-TPM) revealed increased TF expression mediated by JNK2 (n=4; p<0.05). Wild-type and JNK2−/− mice were exposed to cigarette smoke for two weeks after which arterial thrombosis was investigated. Wild-type mice exposed to smoke displayed reduced time to thrombotic arterial occlusion (n=8; p<0.05) and increased tissue factor activity (n=7; p<0.05) as compared to wild-type controls (n=6), while JNK2−/− mice exposed to smoke maintained an unaltered thrombotic potential (n=8; p=NS) and tissue factor activity (n=8) comparable to that of JNK2−/− and wild-type controls (n=6; p=NS). Smoking caused an increased production of reactive oxygen species (ROS) in wild-type but not in JNK2−/− mice (n=7; p<0.05 for wild-type mice and n=5–6; p=NS for JNK2−/− mice). In conclusion, the MAP kinase JNK2 mediates cigarette smoke-induced TF activation, arterial thrombosis and ROS production. These results underscore a major role of JNK2 in smoke-mediated thrombus formation and may offer an attractive target to prevent smoke-related thrombosis in those subjects which do not manage quitting.
Trimethylamine
N
‐Oxide and Mortality Risk in Patients With Peripheral Artery Disease
Authors: Senthong Vichai , Wang Zeneng , Fan Yiying , Wu Yuping , Hazen Stanley L. , Tang W. H. Wilson 
Published: October 2016

Background

Production of the proatherogenic metabolite, trimethylamine
N
‐oxide (
TMAO
), from dietary nutrients by intestinal microbiota enhances atherosclerosis development in animal models and is associated with atherosclerotic coronary artery disease in humans. The utility of studying plasma levels of
TMAO
to risk stratify in patients with peripheral artery disease (
PAD
) has not been reported.

Methods and Results

We examined the relationship between fasting plasma
TMAO
and all‐cause mortality (5‐year), stratified by subtypes of
PAD
and presence of coronary artery disease in 935 patients with
PAD
who underwent elective angiography for cardiac evaluation at a tertiary care hospital. Median plasma
TMAO
was 4.8 μmol/L (interquartile range, 2.9–8.0 μmol/L). Elevated
TMAO
levels were associated with 2.7‐fold increased mortality risk (fourth versus first quartiles, hazard ratio 2.86, 95%
CI
1.82–3.97,
P
<0.001). Following adjustments for traditional risk factors, inflammatory biomarkers, and history of coronary artery disease, the highest
TMAO
quartile remained predictive of 5‐year mortality (adjusted hazard ratio 2.06, 95%
CI
1.36–3.11,
P
<0.001). Similar prognostic value for elevated
TMAO
was seen for subjects with carotid artery, non–carotid artery, or lower extremity
PAD
.
TMAO
provided incremental prognostic value for all‐cause mortality (net reclassification index, 40.22%;
P
<0.001) and improvement in area under receiver operator characteristic curve (65.7% versus 69.4%;
P
=0.013).

Conclusions

TMAO
, a pro‐atherogenic metabolite formed by gut microbes, predicts long‐term adverse event risk and incremental prognostic value in patients with
PAD
. These findings point to the potential for
TMAO
to help improve selection of high‐risk
PAD
patients with or without significant coronary artery disease, who likely need more aggressive and specific dietary and pharmacologic therapy.