bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacterial Surface Spreading Is More Efficient on Nematically Aligned Polysaccharide Substrates
Authors: Lemon David J. , Schutzman Derek A. , Garza Anthony G. 
Published: January 2018

ABSTRACT
Biofilm-forming bacteria typically deposit layers of polysaccharides on the surfaces they inhabit; hence, polysaccharides are their immediate environment on such surfaces. Previously, we showed that many biofilm-forming bacteria preferentially spread in the direction of aligned and densely packed polysaccharide fibers in compressed substrates, a behavior we referred to as polymertropism. This arrangement of polysaccharide fibers is likely to be similar to that found in the “slime” trails deposited by many biofilm-forming bacteria and would explain previous observations that bacteria tend to follow these trails of polysaccharides. Here, we show that groups of cells or flares spread more rapidly on substrates containing aligned and densely packed polysaccharide fibers. Flares also persist longer, tend to hold their trajectories parallel to the long axes of polysaccharide fibers longer, and ultimately show an increase in displacement away from their origin. On the basis of these findings and others, we propose a model for polymertropism. Namely, we suggest that the packing of the aligned polymers increases the efficiency of surface spreading in the direction of the polymer's long axes; therefore, bacteria tend to spread more rapidly in this direction. Additional work suggests that bacteria can leverage polymertropism, and presumably more efficient surface spreading, for a survival advantage. In particular, when two bacterial species were placed in close proximity and in competition with each other, the ability of one species to move rapidly and directly away from the other by utilizing the aligned polymers of compressed agar substrates led to a clear survival benefit.

IMPORTANCE
The directed movement of bacteria on compressed substrates was first described in the 1940s and referred to as elasticotaxis (R. Y. Stanier, J Bacteriol 44:405–412, 1942). More recently, this behavior was referred to as polymertropism, as it seems to be a response to the nematic alignment and tight packing of polymers in the substrate (D. J. Lemon, X. Yang, P. Srivastava, Y. Y. Luk, A. G. Garza, Sci Rep 7:7643, 2017,
https://doi.org/10.1038/s41598-017-07486-0
). The data presented here suggest that bacteria are more efficient at surface spreading when the polymers in the substrate are arranged in this manner. These data also suggest that bacteria can leverage polymertropism, and presumably more efficient surface spreading, for a survival advantage. Namely, one bacterial species was able to use its strong polymertropism response to escape from and survive competition with another species that normally outcompetes it.
Influenza C and D Viruses Package Eight Organized Ribonucleoprotein Complexes
Authors: Nakatsu Sumiho , Murakami Shin , Shindo Keiko , Horimoto Taisuke , Sagara Hiroshi , Noda Takeshi , Kawaoka Yoshihiro 
Published: January 2018

ABSTRACT
Influenza A and B viruses have eight-segmented, single-stranded, negative-sense RNA genomes, whereas influenza C and D viruses have seven-segmented genomes. Each genomic RNA segment exists in the form of a ribonucleoprotein complex (RNP) in association with nucleoproteins and an RNA-dependent RNA polymerase in virions. Influenza D virus was recently isolated from swine and cattle, but its morphology is not fully studied. Here, we examined the morphological characteristics of D/bovine/Yamagata/10710/2016 (D/Yamagata) and C/Ann Arbor/50 (C/AA), focusing on RNPs packaged within the virions. By scanning transmission electron microscopic tomography, we found that more than 70% of D/Yamagata and C/AA virions packaged eight RNPs arranged in the “1+7” pattern as observed in influenza A and B viruses, even though type C and D virus genomes are segmented into only seven segments. These results imply that influenza viruses generally package eight RNPs arranged in the “1+7” pattern regardless of the number of RNA segments in their genome.

IMPORTANCE
The genomes of influenza A and B viruses are segmented into eight segments of negative-sense RNA, and those of influenza C and D viruses are segmented into seven segments. For progeny virions to be infectious, each virion needs to package all of their genomic segments. Several studies support the conclusion that influenza A and B viruses selectively package eight distinct genomic RNA segments; however, the packaging of influenza C and D viruses, which possess seven segmented genomes, is less understood. By using electron microscopy, we showed that influenza C and D viruses package eight RNA segments just as influenza A and B viruses do. These results suggest that influenza viruses prefer to package eight RNA segments within virions independent of the number of genome segments.
Infection and Replication of Influenza Virus at the Ocular Surface
Authors: Creager Hannah M. , Kumar Amrita , Zeng Hui , Maines Taronna R. , Tumpey Terrence M. , Belser Jessica A. 
Published: January 2018

ABSTRACT

Although influenza viruses typically cause respiratory tract disease, some viruses, particularly those with an H7 hemagglutinin, have been isolated from the eyes of conjunctivitis cases. Previous work has shown that isolates of multiple subtypes from both ocular and respiratory infections are capable of replication in human
ex vivo
ocular tissues and corneal or conjunctival cell monolayers, leaving the determinants of ocular tropism unclear. Here, we evaluated the effect of several variables on tropism for ocular cells cultured
in vitro
and examined the potential effect of the tear film on viral infectivity. All viruses tested were able to replicate in primary human corneal epithelial cell monolayers subjected to aerosol inoculation. The temperature at which cells were cultured postinoculation minimally affected infectivity. Replication efficiency, in contrast, was reduced at 33°C relative to that at 37°C, and this effect was slightly greater for the conjunctivitis isolates than for the respiratory ones. With the exception of a seasonal H3N2 virus, the subset of viruses studied in multilayer corneal tissue constructs also replicated productively after either aerosol or liquid inoculation. Human tears significantly inhibited the hemagglutination of both ocular and nonocular isolates, but the effect on viral infectivity was more variable, with tears reducing the infectivity of nonocular isolates more than ocular isolates. These data suggest that most influenza viruses may be capable of establishing infection if they reach the surface of ocular cells but that this is more likely for ocular-tropic viruses, as they are better able to maintain their infectivity during passage through the tear film.

IMPORTANCE
The potential spread of zoonotic influenza viruses to humans represents an important threat to public health. Unfortunately, despite the importance of cellular and tissue tropism to pathogenesis, determinants of influenza virus tropism have yet to be fully elucidated. Here, we sought to identify factors that limit the ability of most influenza viruses to cause ocular infection. Although ocular symptoms in humans caused by avian influenza viruses tend to be relatively mild, these infections are concerning due to the potential of the ocular surface to serve as a portal of entry for viruses that go on to establish respiratory infections. Furthermore, a better understanding of the factors that influence infection and replication in this noncanonical site may point toward novel determinants of tropism in the respiratory tract.
Timing Is Everything
Authors: Schang Luis M. 
Published: January 2018

ABSTRACT

N. Drayman et al. in their recent article (mBio 8:e01612-17, 2017,
https://doi.org/10.1128/mBio.01612-17
) have used dynamic proteomics and machine learning to show that the cell cycle state of any individual cell affects the outcome of a productive herpes simplex virus 1 (HSV-1) infection. Cells infected from early G
1
through S were most permissive for expression of genes from the HSV-1 genome, whereas cells infected in late G
2
to mitosis were much less so. Most of the infected cells that underwent mitosis became permanently nonpermissive for HSV-1 gene expression afterward. The cell cycle stage accounted for 60% of the success of infection, and cell density and motility accounted for most of the rest. To successfully reactivate, HSV-1 must express its genes in neurons and cells of the spinosum and granulosum epidermis strata. These cells are permanently in the cell cycle stages most permissive for HSV-1 gene expression, and none reenters mitosis, thus maximizing the efficiency of a successful HSV-1 reactivation before the adaptive immunity can control it.
Multiple Inhibitory Factors Act in the Late Phase of HIV-1 Replication: a Systematic Review of the Literature
Authors: Gélinas Jean-François , Gill Deborah R. , Hyde Stephen C. 
Published: January 2018

SUMMARY
The use of lentiviral vectors for therapeutic purposes has shown promising results in clinical trials. The ability to produce a clinical-grade vector at high yields remains a critical issue. One possible obstacle could be cellular factors known to inhibit human immunodeficiency virus (HIV). To date, five HIV restriction factors have been identified, although it is likely that more factors are involved in the complex HIV-cell interaction. Inhibitory factors that have an adverse effect but do not abolish virus production are much less well described. Therefore, a gap exists in the knowledge of inhibitory factors acting late in the HIV life cycle (from transcription to infection of a new cell), which are relevant to the lentiviral vector production process. The objective was to review the HIV literature to identify cellular factors previously implicated as inhibitors of the late stages of lentivirus production. A search for publications was conducted on MEDLINE via the PubMed interface, using the keyword sequence “HIV restriction factor” or “HIV restriction” or “inhibit HIV” or “repress HIV” or “restrict HIV” or “suppress HIV” or “block HIV,” with a publication date up to 31 December 2016. Cited papers from the identified records were investigated, and additional database searches were performed. A total of 260 candidate inhibitory factors were identified. These factors have been identified in the literature as having a negative impact on HIV replication. This study identified hundreds of candidate inhibitory factors for which the impact of modulating their expression in lentiviral vector production could be beneficial.
The noninvasive simultaneous measurement of tissue oxygenation and microvascular hemodynamics during incremental handgrip exercise
Authors: Hammer Shane M. , Alexander Andrew M. , Didier Kaylin D. , Smith Joshua R. , Caldwell Jacob T. , Sutterfield Shelbi L. , Ade Carl J. , Barstow Thomas J. 
Published: January 2018

Limb blood flow increases linearly with exercise intensity; however, invasive measurements of muscle microvascular blood flow during incremental exercise have demonstrated submaximal plateaus. We tested the hypotheses that 1) brachial artery blood flow (Q̇BA) would increase with increasing exercise intensity until task failure, 2) blood flow index of the flexor digitorum superficialis (BFIFDS) measured noninvasively via diffuse correlation spectroscopy would plateau at a submaximal work rate, and 3) muscle oxygenation characteristics (total-[heme], deoxy-[heme], and percentage saturation) measured noninvasively with near-infrared spectroscopy would demonstrate a plateau at a similar work rate as BFIFDS. Sixteen subjects (23.3 ± 3.9 yr, 170.8 ± 1.9 cm, 72.8 ± 3.4 kg) participated in this study. Peak power (Ppeak) was determined for each subject (1.8 ± 0.4 W) via an incremental handgrip exercise test. Q̇BA, BFIFDS, total-[heme], deoxy-[heme], and percentage saturation were measured during each stage of the exercise test. On a subsequent testing day, muscle activation measurements of the FDS (RMSFDS) were collected during each stage of an identical incremental handgrip exercise test via electromyography from a subset of subjects ( n = 7). Q̇BA increased with exercise intensity until the final work rate transition ( P < 0.05). No increases in BFIFDS or muscle oxygenation characteristics were observed at exercise intensities greater than 51.5 ± 22.9% of Ppeak. No submaximal plateau in RMSFDS was observed. Whereas muscle activation of the FDS increased until task failure, noninvasively measured indices of perfusive and diffusive muscle microvascular oxygen delivery demonstrated submaximal plateaus. NEW & NOTEWORTHY Invasive measurements of muscle microvascular blood flow during incremental exercise have demonstrated submaximal plateaus. We demonstrate that indices of perfusive and diffusive microvascular oxygen transport to skeletal muscle, measured completely noninvasively, plateau at submaximal work rates during incremental exercise, even though limb blood flow and muscle recruitment continued to increase.
Fiber type-specific analysis of AMPK isoforms in human skeletal muscle: advancement in methods via capillary nanoimmunoassay
Authors: Tobias Irene S. , Lazauskas Kara K. , Arevalo Jose A. , Bagley James R. , Brown Lee E. , Galpin Andrew J. 
Published: January 2018

Human skeletal muscle is a heterogeneous mixture of multiple fiber types (FT). Unfortunately, present methods for FT-specific study are constrained by limits of protein detection in single-fiber samples. These limitations beget compensatory resource-intensive procedures, ultimately dissuading investigators from pursuing FT-specific research. Additionally, previous studies neglected hybrid FT, confining their analyses to only pure FT. Here we present novel methods of protein detection across a wider spectrum of human skeletal muscle FT using fully automated capillary nanoimmunoassay (CNIA) technology. CNIA allowed a ~20-fold-lower limit of 5′-AMP-activated protein kinase (AMPK) detection compared with Western blotting. We then performed FT-specific assessment of AMPK expression as a proof of concept. Individual human muscle fibers were mechanically isolated, dissolved, and myosin heavy chain (MHC) fiber typed via SDS-PAGE. Single-fiber samples were combined in pairs and grouped into MHC I, MHC I/IIa, MHC IIa, and MHC IIa/IIx for expression analysis of AMPK isoforms α1, α2, β1, β2, γ2, and γ3 with a tubulin loading control. Significant FT-specific differences were found for α2 (1.7-fold higher in MHC IIa and MHC IIa/IIx vs. others), γ2 (2.5-fold higher in MHC IIa vs. others), and γ3 (2-fold higher in MHC IIa and 4-fold higher in MHC IIa/IIx vs. others). Development of a protocol that combines the efficient and sensitive CNIA technology with comprehensive SDS-PAGE fiber typing marks an important advancement in FT-specific research because it allows more precise study of the molecular mechanisms governing metabolism, adaptation, and regulation in human muscle. NEW & NOTEWORTHY We demonstrate the viability of applying capillary nanoimmunoassay technology to the study of fiber type-specific protein analysis in human muscle fibers. This novel technique enables a ~20-fold-lower limit of protein detection compared with traditional Western blotting methods. Combined with SDS-PAGE methods of fiber typing, we apply this technique to compare 5′-AMP-activated protein kinase isoform expression in myosin heavy chain (MHC) I, MHC I/IIa, MHC IIa, and MHC IIa/IIx fiber types.
Intermittent hypoxia in utero damages postnatal growth and cardiovascular function in rats
Authors: Chen Ling , Zadi Zahra Heidari , Zhang Jin , Scharf Steven M. , Pae Eung-Kwon 
Published: January 2018

Obstructive sleep apnea (OSA) is common in pregnancy and may compromise fetal and even postnatal development. We developed an animal model to determine if maternal OSA could have lasting effects in offspring. Pregnant Sprague-Dawley rats were exposed to reduced ambient O2 from 21 to 4–5%, approximately once per minute [chronic intermittent hypoxia (CIH)] for 8 h/day during gestation days 3–19. Similarly handled animals exposed to ambient air served as controls (HC). Offspring were studied for body growth and cardiovascular function for 8 postnatal weeks. Compared with HC, prenatal CIH led to growth restriction, indicated by smaller body weight and tibial length, and higher arterial blood pressure in both male and female offspring. Compared with same-sex HC, CIH males showed abdominal obesity (greater ratio of abdominal fat weight to body weight or tibial length), left ventricular (LV) hypertrophy (greater heart weight-to-tibial length ratio and LV posterior wall diastolic thickness), elevated LV contractility (increases in LV ejection fraction, end-systolic pressure-volume relations, and preload recruitable stroke work), elevated LV and arterial stiffness (increased end-diastolic pressure-volume relationship and arterial elasticity), and LV oxidative stress (greater lipid peroxide content). Compared with female CIH offspring, male CIH offspring had more profound changes in blood pressure (BP), cardiac function, myocardial lipid peroxidase (LPO) content, and abdominal adiposity. Rodent prenatal CIH exposure, mimicking human maternal OSA, exerts detrimental morphological and cardiovascular effects on developing offspring; the model may provide useful insights of OSA effects in humans. NEW & NOTEWORTHY Obstructive sleep apnea is common in human pregnancy. Following maternal exposure to chronic intermittent hypoxia, a hallmark of sleep apnea, both sexes of rat offspring showed growth retardation, with males being more vulnerable to hypertension and dysfunctional left ventricular changes. This model is useful to study detrimental effects of maternal obstructive sleep apnea on developing offspring in humans.
Long Noncoding RNA pancEts-1 Promotes Neuroblastoma Progression through hnRNPK-Mediated β-Catenin Stabilization
Authors: Li Dan , Wang Xiaojing , Mei Hong , Fang Erhu , Ye Lin , Song Huajie , Yang Feng , Li Huanhuan , Huang Kai , Zheng Liduan , Tong Qiangsong 
Published: January 2018

Abstract
Long noncoding RNAs (lncRNA) play essential roles in tumor progression. However, the functions of lncRNAs in the tumorigenesis and aggressiveness of neuroblastoma still remain to be determined. Here, we report the identification of lncRNA pancEts-1 as a novel driver of neuroblastoma progression by using a public microarray dataset. LncRNA pancEts-1 promoted the growth, invasion, and metastasis of neuroblastoma cells in vitro and in vivo. Mechanistically, pancEts-1 bound to hnRNPK to facilitate its physical interaction with β-catenin, whereas hnRNPK stabilized the β-catenin by inhibiting proteasome-mediated degradation, resulting in transcriptional alteration of target genes associated with neuroblastoma progression. Both pancEts-1 and hnRNPK were upregulated in clinical neuroblastoma tissues, and were associated with unfavorable outcome of patients. Overall, our results define an oncogenic role of pancEts-1 in neuroblastoma progression through hnRNPK-mediated β-catenin stabilization, with potential implications for the clinical therapeutics of neuroblastoma.
Significance: These findings reveal the oncogenic functions of a long noncoding RNA in neuroblastoma progression, offering a potential target for clinical therapeutics. Cancer Res; 78(5); 1169–83. ©2018 AACR.
Night Shift Work Increases the Risks of Multiple Primary Cancers in Women: A Systematic Review and Meta-analysis of 61 Articles
Authors: Yuan Xia , Zhu Chenjing , Wang Manni , Mo Fei , Du Wei , Ma Xuelei 
Published: January 2018

AbstractA growing number of studies have examined associations between night shift work and the risks of common cancers among women, with varying conclusions. We did a meta-analysis to identify whether long-term night shift work increased the risks of common cancers in women. We enrolled 61 articles involving 114,628 cases and 3,909,152 participants from Europe, North America, Asia, and Australia. Risk estimates were performed with a random-effect model or a fixed-effect model. Subgroup analyses and meta-regression analyses about breast cancer were conducted to explore possible sources of heterogeneity. In addition, we carried out a dose–response analysis to quantitatively estimate the accumulative effect of night shift work on the risk of breast cancer. A positive relationship was revealed between long-term night shift work and the risks of breast [OR = 1.316; 95% confidence interval (CI), 1.196–1.448], digestive system (OR = 1.177; 95% CI, 1.065–1.301), and skin cancer (OR = 1.408; 95% CI, 1.024–1.934). For every 5 years of night shift work, the risk of breast cancer in women was increased by 3.3% (OR = 1.033; 95% CI, 1.012–1.056). Concerning the group of nurses, long-term night shift work presented potential carcinogenic effect in breast cancer (OR = 1.577; 95% CI, 1.235–2.014), digestive system cancer (OR = 1.350; 95% CI, 1.030–1.770), and lung cancer (OR = 1.280; 95% CI, 1.070–1.531). This systematic review confirmed the positive association between night shift work and the risks of several common cancers in women. We identified that cancer risk of women increased with accumulating years of night shift work, which might help establish and implement effective measures to protect female night shifters. Cancer Epidemiol Biomarkers Prev; 27(1); 25–40. ©2018 AACR.
Collapsing the Tumor Ecosystem: Preventing Adaptive Response to Treatment by Inhibiting Transcription
Authors: Carugo Alessandro , Draetta Giulio F. 
Published: January 2018

Abstract
Summary: Adaptation and resistance to treatment are the results of a multitude of (epi)genetic events unmasked or directly triggered by therapies targeting the genetic driver(s) of a dominant cell population within a tumor mass. Rusan and colleagues report that drug-tolerant cells are sensitive to THZ1, a dual CDK7/12 inhibitor, which, by impairing the transcriptional machinery, can prevent cellular rewiring to survive therapeutic attack. Cancer Discov; 8(1); 17–9. ©2018 AACR.
See related article by Rusan et al., p. 59.
Genomic insights into Mycobacterium simiae human colonization
Authors: Steffani-Vallejo José L. , Brunck Marion E. , Acosta-Cruz Erika Y. , Montiel Rafael , Barona-Gómez Francisco 
Published: January 2018

AbstractMycobacterium simiae (Karassova V, Weissfeiler J, Kraszanay E, Acta Microbiol Acad Sci Hung 12:275-82, 1965) is a slow-growing nontuberculous Mycobacterium species found in environmental niches, and recently evidenced as an opportunistic Human pathogen. We report here the genome of a clinical isolate of M. simiae (MsiGto) obtained from a patient in Guanajuato, Mexico. With a size of 6,684,413 bp, the genomic sequence of strain MsiGto is the largest of the three M. simiae genomes reported to date. Gene prediction revealed 6409 CDSs in total, including 6354 protein-coding genes and 52 RNA genes. Comparative genomic analysis identified shared features between strain MsiGto and the other two reported M. simiae genomes, as well as unique genes. Our data reveals that M. simiae MsiGto harbors virulence-related genes, such as arcD, ESAT-6, and those belonging to the antigen 85 complex and mce clusters, which may explain its successful transition to the human host. We expect the genome information of strain MsiGto will provide a better understanding of infective mechanisms and virulence of this emergent pathogen.