bluuebunny/crossref_metadata_2025_split huggingface dataset:
Authentic Patient-Derived Hepatitis C Virus Infects and Productively Replicates in Primary CD4
+
and CD8
+
T Lymphocytes
In Vitro
Authors: Skardasi Georgia , Chen Annie Y. , Michalak Tomasz I. 
Published: November 2017

ABSTRACT

Accumulated evidence indicates that immune cells can support the replication of hepatitis C virus (HCV) in infected patients and in culture. However, there is a scarcity of data on the degree to which individual immune cell types support HCV propagation and on characteristics of virus assembly. We investigated the ability of authentic, patient-derived HCV to infect
in vitro
two closely related but functionally distinct immune cell types, CD4
+
and CD8
+
T lymphocytes, and assessed the properties of the virus produced by these cells. The HCV replication system in intermittently mitogen-stimulated T cells was adapted to infect primary human CD4
+
or CD8
+
T lymphocytes. HCV replicated in both cell types although at significantly higher levels in CD4
+
than in CD8
+
T cells. Thus, the HCV RNA replicative (negative) strand was detected in CD4
+
and CD8
+
cells at estimated mean levels ± standard errors of the means of 6.7 × 10
2
± 3.8 × 10
2
and 1.2 × 10
2
± 0.8 × 10
2
copies/μg RNA, respectively (
P
< 0.0001). Intracellular HCV NS5a and/or core proteins were identified in 0.9% of CD4
+
and in 1.2% of CD8
+
T cells. Double staining for NS5a and T cell type-specific markers confirmed that transcriptionally competent virus replicated in both cell types. Furthermore, an HCV-specific protease inhibitor, telaprevir, inhibited infection in both CD4
+
and CD8
+
cells. The emergence of unique HCV variants and the release of HCV RNA-reactive particles with biophysical properties different from those of virions in plasma inocula suggested that distinct viral particles were assembled, and therefore, they may contribute to the pool of circulating virus in infected patients.

IMPORTANCE
Although the liver is the main site of HCV replication, infection of the immune system is an intrinsic characteristic of this virus independent of whether infection is symptomatic or clinically silent. Many fundamental aspects of HCV lymphotropism remain uncertain, including the degree to which different immune cells support infection and contribute to virus diversity. We show that authentic, patient-derived HCV productively replicates
in vitro
in two closely related but functionally distinct types of T lymphocytes, CD4
+
and CD8
+
cells. The display of viral proteins and unique variants, the production of virions with biophysical properties distinct from those in plasma serving as inocula, and inhibition of replication by an antiviral agent led us to ascertain that both T cell subtypes supported virus propagation. Infection of CD4
+
and CD8
+
T cells, which are central to adaptive antiviral immune responses, can directly affect HCV clearance, favor virus persistence, and decisively influence the development and progression of hepatitis C.
Three-Dimensional Superresolution Imaging of the FtsZ Ring during Cell Division of the Cyanobacterium
Prochlorococcus
Authors: Liu Riyue , Liu Yaxin , Liu Shichang , Wang Ying , Li Kim , Li Ning , Xu Daiying , Zeng Qinglu 
Published: November 2017

ABSTRACT

Superresolution imaging has revealed subcellular structures and protein interactions in many organisms. However, superresolution microscopy with lateral resolution better than 100 nm has not been achieved in photosynthetic cells due to the interference of a high-autofluorescence background. Here, we developed a photobleaching method to effectively reduce the autofluorescence of cyanobacterial and plant cells. We achieved lateral resolution of ~10 nm with stochastic optical reconstruction microscopy (STORM) in the sphere-shaped cyanobacterium
Prochlorococcus
and the flowering plant
Arabidopsis thaliana
. During the cell cycle of
Prochlorococcus
, we characterized the three-dimensional (3D) organization of the cell division protein FtsZ, which forms a ring structure at the division site and is important for cytokinesis of bacteria and chloroplasts. Although the FtsZ ring assembly process in rod-shaped bacteria has been studied extensively, it has rarely been studied in sphere-shaped bacteria. Similarly to rod-shaped bacteria, our results with
Prochlorococcus
also showed the assembly of FtsZ clusters into incomplete rings and then complete rings during cell division. Differently from rod-shaped bacteria, the FtsZ ring diameter was not found to decrease during
Prochlorococcus
cell division. We also discovered a novel double-Z-ring structure, which may be the Z rings of two daughter cells in a predivisional mother cell. Our results showed a quantitative picture of the
in vivo
Z ring organization of sphere-shaped bacteria.

IMPORTANCE
Superresolution microscopy has not been widely used to study photosynthetic cells due to their high-autofluorescence background. Here, we developed a photobleaching method to reduce the autofluorescence of cyanobacteria and plant cells. After photobleaching, we performed superresolution imaging in the cyanobacterium
Prochlorococcus
and the flowering plant
Arabidopsis thaliana
with ~10-nm resolution, which is the highest resolution in a photosynthetic cell. With this method, we characterized the 3D organization of the cell division protein FtsZ in
Prochlorococcus
. We found that the morphological variation of the FtsZ ring during cell division of the sphere-shaped cyanobacterium
Prochlorococcus
is similar but not identical to that of rod-shaped bacteria. Our method might also be applicable to other photosynthetic organisms.
Perceptually-guided foveation for light field displays
Authors: Sun Qi , Huang Fu-Chung , Kim Joohwan , Wei Li-Yi , Luebke David , Kaufman Arie 
Published: November 2017

A variety of applications such as virtual reality and immersive cinema require high image quality, low rendering latency, and consistent depth cues. 4D light field displays support focus accommodation, but are more costly to render than 2D images, resulting in higher latency.
The human visual system can resolve higher spatial frequencies in the fovea than in the periphery. This property has been harnessed by recent 2D foveated rendering methods to reduce computation cost while maintaining perceptual quality. Inspired by this, we present foveated 4D light fields by investigating their effects on 3D depth perception. Based on our psychophysical experiments and theoretical analysis on visual and display bandwidths, we formulate a content-adaptive importance model in the 4D ray space. We verify our method by building a prototype light field display that can render only 16% -- 30% rays without compromising perceptual quality.
Irritable bowel syndrome patients haveSCN5Achannelopathies that lead to decreased NaV1.5 current and mechanosensitivity
Authors: Strege Peter R. , Mazzone Amelia , Bernard Cheryl E. , Neshatian Leila , Gibbons Simon J. , Saito Yuri A. , Tester David J. , Calvert Melissa L. , Mayer Emeran A. , Chang Lin , Ackerman Michael J. , Beyder Arthur , Farrugia Gianrico 
Published: November 2017

The SCN5A-encoded voltage-gated mechanosensitive Na+channel NaV1.5 is expressed in human gastrointestinal smooth muscle cells and interstitial cells of Cajal. NaV1.5 contributes to smooth muscle electrical slow waves and mechanical sensitivity. In predominantly Caucasian irritable bowel syndrome (IBS) patient cohorts, 2–3% of patients have SCN5A missense mutations that alter NaV1.5 function and may contribute to IBS pathophysiology. In this study we examined a racially and ethnically diverse cohort of IBS patients for SCN5A missense mutations, compared them with IBS-negative controls, and determined the resulting NaV1.5 voltage-dependent and mechanosensitive properties. All SCN5A exons were sequenced from somatic DNA of 252 Rome III IBS patients with diverse ethnic and racial backgrounds. Missense mutations were introduced into wild-type SCN5A by site-directed mutagenesis and cotransfected with green fluorescent protein into HEK-293 cells. NaV1.5 voltage-dependent and mechanosensitive functions were studied by whole cell electrophysiology with and without shear force. Five of 252 (2.0%) IBS patients had six rare SCN5A mutations that were absent in 377 IBS-negative controls. Six of six (100%) IBS-associated NaV1.5 mutations had voltage-dependent gating abnormalities [current density reduction (R225W, R433C, R986Q, and F1293S) and altered voltage dependence (R225W, R433C, R986Q, G1037V, and F1293S)], and at least one kinetic parameter was altered in all mutations. Four of six (67%) IBS-associated SCN5A mutations (R225W, R433C, R986Q, and F1293S) resulted in altered NaV1.5 mechanosensitivity. In this racially and ethnically diverse cohort of IBS patients, we show that 2% of IBS patients harbor SCN5A mutations that are absent in IBS-negative controls and result in NaV1.5 channels with abnormal voltage-dependent and mechanosensitive function.NEW & NOTEWORTHY The voltage-gated Na+channel NaV1.5 contributes to smooth muscle physiology and electrical slow waves. In a racially and ethnically mixed irritable bowel syndrome cohort, 2% had mutations in the NaV1.5 gene SCN5A. These mutations were absent in irritable bowel syndrome-negative controls. Most mutant NaV1.5 channels were loss of function in voltage dependence or mechanosensitivity.
Exocrine pancreas glutamate secretion help to sustain enterocyte nutritional needs under protein restriction
Authors: Araya S. , Kuster E. , Gluch D. , Mariotta L. , Lutz C. , Reding T. V. , Graf R. , Verrey F. , Camargo S. M. R. 
Published: November 2017

Glutamine (Gln) is the most concentrated amino acid in blood and considered conditionally essential. Its requirement is increased during physiological stress, such as malnutrition or illness, despite its production by muscle and other organs. In the malnourished state, Gln has been suggested to have a trophic effect on the exocrine pancreas and small intestine. However, the Gln transport capacity, the functional relationship of these two organs, and the potential role of the Gln-glutamate (Glu) cycle are unknown. We observed that pancreatic acinar cells express lower levels of Glu than Gln transporters. Consistent with this expression pattern, the rate of Glu influx into acinar cells was approximately sixfold lower than that of Gln. During protein restriction, acinar cell glutaminase expression was increased and Gln accumulation was maintained. Moreover, Glu secretion by acinar cells into pancreatic juice and thus into the lumen of the small intestine was maintained. In the intestinal lumen, Glu absorption was preserved and Glu dehydrogenase expression was augmented, potentially providing the substrates for increasing energy production via the TCA cycle. Our findings suggest that one mechanism by which Gln exerts a positive effect on exocrine pancreas and small intestine involves the Gln metabolism in acinar cells and the secretion of Glu into the small intestine lumen. The exocrine pancreas acinar cells not only avidly accumulate Gln but metabolize Gln to generate energy and to synthesize Glu for secretion in the pancreatic juice. Secreted Glu is suggested to play an important role during malnourishment in sustaining small intestinal homeostasis.NEW & NOTEWORTHY Glutamine (Gln) has been suggested to have a trophic effect on exocrine pancreas and small intestine in malnourished states, but the mechanism is unknown. In this study, we suggest that this trophic effect derives from an interorgan relationship between exocrine pancreas and small intestine for Gln-glutamate (Glu) utilization involving the uptake and metabolism of Gln in acinar cells and secretion of Glu into the lumen of the small intestine.
Learning-induced modulation of the effect of endocannabinoids on inhibitory synaptic transmission
Authors: Ghosh Sourav , Reuveni Iris , Zidan Samaa , Lamprecht Raphael , Barkai Edi 
Published: November 2017

Endocannabinoids are key modulators that regulate central brain functions and behaviors, including learning and memory. At the cellular and molecular levels, endocannabinoids are potent modulators of excitatory and inhibitory synaptic function. Most effects of cannabinoids are thought to be mediated via G protein-coupled cannabinoid receptors. In particular, cannabinoids released from postsynaptic neurons are suggested to act as retrograde messengers, activating presynaptic type-1 cannabinoid receptors (CB1Rs), thereby inducing suppression of synaptic release. Another central mechanism of cannabinoid-induced action requires activation of astroglial CB1Rs. CB1Rs are also implicated in self-modulation of cortical neurons. Rats that are trained in a particularly difficult olfactory-discrimination task show a dramatic increased ability to acquire memories of new odors. The memory of the acquired high-skill acquisition, termed “rule learning” or “learning set,” lasts for many months. Using this behavioral paradigm, we show a novel function of action for CB1Rs, supporting long-term memory by maintaining persistent enhancement of inhibitory synaptic transmission. Long-lasting enhancement of inhibitory synaptic transmission is blocked by a CB1R inverse agonist. This effect is mediated by a novel purely postsynaptic mechanism, obtained by enhancing the single GABAA channel conductance that is PKA dependent. The significant role that CB1R has in maintaining learning-induced long-term strengthening of synaptic inhibition suggests that endocannabinoids have a key role in maintaining long-term memory by enhancing synaptic inhibition. NEW & NOTEWORTHY In this study we show a novel function and mechanism of action for cannabinoids in neurons, mediated by activation of type-1 cannabinoid receptors, supporting long-term memory by maintaining persistent enhancement of inhibitory synaptic transmission on excitatory neurons. This effect is mediated by a novel purely postsynaptic mechanism, obtained by enhancing the single GABAA channel conductance that is PKA dependent. Thus we report for the first time that endocannabinoids have a key role maintaining learning-induced synaptic modification.
PTEN Loss Promotes Intratumoral Androgen Synthesis and Tumor Microenvironment Remodeling via Aberrant Activation of RUNX2 in Castration-Resistant Prostate Cancer
Authors: Yang Yinhui , Bai Yang , He Yundong , Zhao Yu , Chen Jiaxiang , Ma Linlin , Pan Yunqian , Hinten Michael , Zhang Jun , Karnes R. Jeffrey , Kohli Manish , Westendorf Jennifer J. , Li Benyi , Zhu Runzhi , Huang Haojie , Xu Wanhai 
Published: November 2017

Abstract
Purpose: Intratumoral androgen synthesis (IAS) is a key mechanism promoting androgen receptor (AR) reactivation and antiandrogen resistance in castration-resistant prostate cancer (CRPC). However, signaling pathways driving aberrant IAS remain poorly understood.
Experimental Design: The effect of components of the AKT-RUNX2-osteocalcin (OCN)–GPRC6A–CREB signaling axis on expression of steroidogenesis genes CYP11A1 and CYP17A1 and testosterone level were examined in PTEN-null human prostate cancer cell lines. Pten knockout mice were used to examine the effect of Runx2 heterozygous deletion or abiraterone acetate (ABA), a prodrug of the CYP17A1 inhibitor abiraterone on Cyp11a1 and Cyp17a1 expression, testosterone level and tumor microenvironment (TME) remodeling in vivo.
Results: We uncovered that activation of the AKT–RUNX2–OCN–GPRC6A–CREB signaling axis induced expression of CYP11A1 and CYP17A1 and testosterone production in PTEN-null prostate cancer cell lines in culture. Deletion of Runx2 in Pten homozygous knockout prostate tumors decreased Cyp11a1 and Cyp17a1 expression, testosterone level, and tumor growth in castrated mice. ABA treatment also inhibited testosterone synthesis and alleviated Pten loss-induced tumorigenesis in vivo. Pten deletion induced TME remodeling, but Runx2 heterozygous deletion or ABA treatment reversed the effect of Pten loss by decreasing expression of the collagenase Mmp9.
Conclusions: Abnormal RUNX2 activation plays a pivotal role in PTEN loss-induced IAS and TME remodeling, suggesting that the identified signaling cascade represents a viable target for effective treatment of PTEN-null prostate cancer, including CRPC. Clin Cancer Res; 24(4); 834–46. ©2017 AACR.
Pericardial Adipose Tissue Regulates Granulopoiesis, Fibrosis, and Cardiac Function After Myocardial Infarction
Authors: Horckmans Michael , Bianchini Mariaelvy , Santovito Donato , Megens Remco T.A. , Springael Jean-Yves , Negri Irene , Vacca Michele , Di Eusanio Marco , Moschetta Antonio , Weber Christian , Duchene Johan , Steffens Sabine 
Published: November 2017

Background:
The pericardial adipose tissue (AT) contains a high density of lymphoid clusters. It is unknown whether these clusters play a role in post–myocardial infarction (MI) inflammatory responses and cardiac outcome.

Methods:

Lymphoid clusters were examined in epicardial AT of humans with or without coronary artery disease. Murine pericardial lymphoid clusters were visualized in mice subjected to coronary artery ligation. To study the relevance of pericardial clusters during inflammatory responses after MI, we surgically removed the pericardial AT and performed B-cell depletion and granulocyte-macrophage colony-stimulating factor blockade. Leukocytes in murine hearts, pericardial AT, spleen, mediastinal lymph nodes, and bone marrow were quantified by flow cytometry. Cannabinoid receptor CB2 (CB2
–/–
) mice were used as a model for enhanced B-cell responses. The effect of impaired dendritic cell (DC) trafficking on pericardial AT inflammatory responses was tested in CCR7
–/–
mice subjected to MI. Cardiac fibrosis and ventricular function were assessed by histology and echocardiography.

Results:

We identified larger B-cell clusters in epicardial AT of human patients with coronary artery disease in comparison with controls without coronary artery disease. Infarcted mice also had larger pericardial clusters and 3-fold upregulated numbers of granulocyte-macrophage colony-stimulating factor–producing B cells within pericardial AT, but not spleen or lymph nodes. This was associated with higher DC and T-cell counts in pericardial AT, which outnumbered DCs and T cells in lymph nodes. Analysis of DC maturation markers, tracking experiments with fluorescently labeled cells, and use of CCR7-deficient mice suggested that activated DCs migrate from infarcts into pericardial AT via CCR7. B-cell depletion or granulocyte-macrophage colony-stimulating factor neutralization inhibited DC and T-cell expansion within pericardial AT, and translated into reduced bone marrow granulopoiesis and cardiac neutrophil infiltration 3 days after MI. The relevance of the pericardial AT in mediating all these effects was confirmed by removal of pericardial AT and ex vivo coculture with pericardial AT and granulocyte progenitors. Finally, enhanced fibrosis and worsened ejection fraction in CB2
–/–
mice were limited by pericardial AT removal.

Conclusions:
Our findings unveil a new mechanism by which the pericardial AT coordinates immune cell activation, granulopoiesis, and outcome after MI.
Ischemic Stroke Profile, Risk Factors, and Outcomes in India
Authors: Sylaja P.N. , Pandian Jeyaraj Durai , Kaul Subhash , Srivastava M.V. Padma , Khurana Dheeraj , Schwamm Lee H. , Kesav Praveen , Arora Deepti , Pannu Aman , Thankachan Tijy K. , Singhal Aneesh B. 
Published: November 2017

Background and Purpose—
The Indo-US Collaborative Stroke Project was designed to characterize ischemic stroke across 5 high-volume academic tertiary hospitals in India.

Methods—
From January 2012 to August 2014, research coordinators and physician coinvestigators prospectively collected data on 2066 patients with ischemic stroke admitted <2 weeks after onset. Investigator training and supervision and data monitoring were conducted by the US site (Massachusetts General Hospital, Boston).

Results—
The mean age was 58.3±14.7 years, 67.2% men. The median admission National Institutes of Health Stroke Scale score was 10 (interquartile range, 5–15) and 24.5% had National Institutes of Health Stroke Scale ≥16. Hypertension (60.8%), diabetes mellitus (35.7%), and tobacco use (32.2%, including bidi/smokeless tobacco) were common risk factors. Only 4% had atrial fibrillation. All patients underwent computed tomography or magnetic resonance imaging; 81% had cerebrovascular imaging. Stroke etiologic subtypes were large artery (29.9%), cardiac (24.9%), small artery (14.2%), other definite (3.4%), and undetermined (27.6%, including 6.7% with incomplete evaluation). Intravenous or intra-arterial thrombolysis was administered in 13%. In-hospital mortality was 7.9%, and 48% achieved modified Rankin Scale score 0 to 2 at 90 days. On multivariate analysis, diabetes mellitus predicted poor 3-month outcome and younger age, lower admission National Institutes of Health Stroke Scale and small-artery etiology predicted excellent 3-month outcome.

Conclusions—
These comprehensive and novel clinical imaging data will prove useful in refining stroke guidelines and advancing stroke care in India.
Refusing Treatment Prior to Becoming Incapacitated: Supported Decision-making as an Approach in Advance Directives
Authors: Chan Hui Yun 
Published: November 2017

Abstract
Advance directives (ads) provide people with the opportunity to express their wishes about treatment preferences prior to becoming incapacitated. While the normative logic behind ads remain straightforward, as instruments of law they are not always effective because of questions about their validity and applicability. It is on this basis that this article attempts to resolve the legal intricacies on ads refusing treatment prior to becoming incapacitated. The author advances a thesis in support of a modification of an approach known as supported decision-making to facilitate people in making ads. This approach pre-empts most of the doubts about an ad’s validity. The argument is founded on the presumption that an ad made using the supported decision-making approach provides a higher degree of assurance about the circumstances surrounding the making of ads, rendering it more likely to be binding on healthcare professionals.
Evaluation Influence: The Evaluation Event and Capital Flow in International Development
Authors: Bell David A. 
Published: November 2017

Background: Assessing program effectiveness in human development is central to informing foreign aid policy-making and organizational learning. Foreign aid effectiveness discussions have increasingly given attention to the devaluing effects of aid flow volatility. This study reveals that the external evaluation event influences actor behavior, serving as a volatility-constraining tool. Method: A case study of a multidonor aid development mechanism served examining the influence of an evaluation event when considering anticipatory effects. The qualitative component used text and focus group data combined with individual interview data (organizations n = 10, including 26 individuals). Quantitative data included financial information on all 75 capital investments. The integrated theory of influence and model of alternative mechanisms used these components to identify the linkage between the evaluation event and capital flow volatility. Results: Aid approved in the year of the midterm evaluation was disbursed by the mechanism with low capital volatility. Anticipating the evaluation event influenced behavior resulting in an empirical record that program outcomes were enhanced and the mechanism was an improved organization. Implications: Formative evaluations in a development program can trigger activity as an interim process. That activity provides for a more robust assessment of ultimate consequence of interest. Anticipating an evaluation can stimulate donor reality testing. The findings inform and strengthen future research on the influence of anticipating an evaluation. Closely examining activities before, during, and shortly after the evaluation event can aid development of other systematic methods to improve understanding this phenomenon, as well as improve donor effectiveness strategies.