bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure and Drug Binding of the SARS-CoV-2 Envelope Protein in Phospholipid Bilayers
Authors: Hong Mei , Mandala Venkata , McKay Matthew , Shcherbakov Alexander , Dregni Aurelio , Kolocouris Antonios 
Published: September 2020

Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the ongoing COVID-19 pandemic. Successful development of vaccines and antivirals against SARS-CoV-2 requires a comprehensive understanding of the essential proteins of the virus. The envelope (E) protein of SARS-CoV-2 assembles into a cation-selective channel that mediates virus budding, release, and host inflammation response. E blockage reduces virus pathogenicity while E deletion attenuates the virus. Here we report the 2.4 Å structure and drug-binding site of E’s transmembrane (TM) domain, determined using solid-state nuclear magnetic resonance (NMR) spectroscopy. In lipid bilayers that mimic the endoplasmic reticulum Golgi intermediate compartment (ERGIC) membrane, ETM forms a five-helix bundle surrounding a narrow central pore. The middle of the TM segment is distorted from the ideal a-helical geometry due to three regularly spaced phenylalanine residues, which stack within each helix and between neighboring helices. These aromatic interactions, together with interhelical Val and Leu interdigitation, cause a dehydrated pore compared to the viroporins of influenza and HIV viruses. Hexamethylene amiloride and amantadine bind shallowly to polar residues at the N-terminal lumen, while acidic pH affects the C-terminal conformation. These results indicate that SARS-CoV-2 E forms a structurally robust but bipartite channel whose N- and C-terminal halves can interact with drugs, ions and other viral and host proteins semi-independently. This structure establishes the atomic basis for designing E inhibitors as antiviral drugs against SARS-CoV-2.
Joint Spectral Efficiency Optimization of Uplink and Downlink for Massive MIMO Enabled Wireless Energy Harvesting Systems
Authors: Sun Wenfeng , Liu Chen , Qian Mujun , Chen Yan , Xu Shu 
Published: September 2020

Abstract
This paper proposes a unified system model and uses a general wireless energy harvesting (EH) protocol in massive multiple-input multiple-output (MIMO) systems, in which the terminals have no fixed power supply and thus need to replenish energy via the received signals from the base station (BS). On the downlink, the BS delivers radio frequency (RF) signals to all terminals and each terminal coordinates the processes of EH and information decoding (ID) with wireless EH protocol. On the uplink, a fraction of the harvested energy is used for uplink pilot transmission and the remaining fraction is used for uplink data transmission. Closed-form lower bound expressions for each terminal are first obtained on the uplink and downlink, respectively. Based on these expressions, we then formulate the joint spectral efficiency (SE) of uplink and downlink maximization problem with some practical constraints. As the formulated optimization problem is non-linear and non-convex, it is hard to solve directly. To provide a solution, an iteration algorithm is proposed by utilizing one-dimensional search technique and successive approximation method based on geometric program (GP). Additionally, the convergence and complexity of the proposed algorithm are discussed as well. Finally, the feasibility of the proposed algorithm and analytical results are demonstrated by extensive computer simulations.
Pathogenicity, immunogenicity, and protective ability of an attenuated SARS-CoV-2 variant with a deletion at the S1/S2 junction of the spike protein
Authors: Wang Pui , Lau Siu-Ying , Deng Shaofeng , Chen Pin , Mok Bobo , Zhang Jinxia , Lee Andrew , Chan Kwok-Hung , Tam Rachel , Song Wenjun , To Kelvin , Chan Jasper , Yuen Kwok-Yung , Chen Honglin 
Published: September 2020

Abstract
SARS-CoV-2 is zoonotic origin and contains a PRRA polybasic cleavage motif which is considered critical for efficient infection and transmission in humans. We previously reported on a panel of attenuated SARS-CoV-2 variants with deletion at the S1/S2 junction of spike protein. Here we characterize pathogenicity, immunogenicity, and protective ability of a further cell-adapted SARS-CoV-2 variant, Ca-DelMut, in in vitro and in vivo systems. Ca-DelMut replicates more efficiently than wild type or parental virus in cells, but causes no apparent disease in hamsters, despite replicating in respiratory tissues. Unlike wild type virus, Ca-DelMut causes no apparent pathological changes and does not induce elevated proinflammatory cytokines in hamster infections, but still triggers a strong neutralizing antibody response in hamsters. Ca-DelMut immunized hamsters challenged with wild type SARS-CoV-2 are fully protected with no sign of virus replication in the upper or lower respiratory tract of challenged animals, demonstrating sterilizing immunity.
Prevalence of Plasmodium falciparum Isolates Lacking the Histidine Rich Protein 2 Gene Among Symptomatic Malaria Patients in Kwilu Province, DR. Congo.
Authors: Munyeku Yannick Bazitama , Musaka Alain Abera , Ernest Medard , Smith Chris , Mansiangi Paul Mankadi , Culleton Richard 
Published: September 2020

Abstract
BackgroundMalaria rapid diagnostic tests have become a primary and critical tool for malaria diagnosis in malaria-endemic countries where PfHRP2-based RDTs are widely used. However, in the last decade, the accuracy of PfHRP2-based RDTs has been challenged by the emergence of P. falciparum strains harbouring deletions of the pfhrp2 gene, resulting in false-negative results. In DR. Congo, little is known about the prevalence of the pfhrp2 gene deletion among P. falciparum isolates infecting symptomatic patients, especially in low to moderate transmission areas where pfhrp2 deletion parasites are assumed to emerge and spread. Here we determine the local prevalence and factors associated with pfhrp2 gene deletions among symptomatic malaria patients in the Kwilu province of the Democratic Republic of Congo, a low to moderate malaria transmission area.MethodsWe used secondary data from a prospective health facility-based cross-sectional study conducted on 684 individuals of all ages, seeking healthcare with symptoms suggestive of malaria from October to December 2018 in 34 randomly selected health facilities. Sociodemographic, malaria prevention and treatment practices, and clinical variables were collected using a pre-tested structured questionnaire. Patients’ medical records were used to collect additional clinical data. Blood was collected for microscopy, PfHRP2-RDT, and spotted onto Whatman filter paper for downstream genetic analysis. Genomic DNA was extracted and used to perform PCR assays for the detection and confirmation of pfhrp2 gene deletions. Data were entered and analysed using STATA15. Fischer’s exact and the Kruskal-Wallis tests were applied to look for associations between exposures and the pfhrp2 gene deletion with a level of statistical significance set at p < 0.05. ResultsThe overall prevalence of the pfhrp2 gene deletion was 9.2% (95% CI 6.7% – 12.1%). The deletion of the pfhrp2 gene was associated with health zone of origin (p=0.012) and age (p=0.019). Among false-negative PfHRP2-RDT results, only 9.9% were due to pfhrp2 gene deletion.ConclusionP. falciparum isolates with pfhrp2 gene deletions are relatively common among symptomatic patients in Kwilu province. Further investigations are needed to provide enough evidence for policy change. Meanwhile, the use of RDTs targeting PfHRP2 and pLDH antigens could limit the spread of deleted isolates.
Smoking and Inequalities in Mortality in 11 European Countries: A Birth Cohort Analysis
Authors: Long Di , Nusselder Wilma , Martikainen Pekke , Lundberg Olle , Brønnum-Hansen Henrik , Bopp Matthias , Costa Giuseppe , Kovács Katalin , Leinsalu Mall , Rodríguez-Sanz Maica , Menvielle Gwenn , Mackenbach Johan 
Published: September 2020

Abstract
Purpose: To study the trends of smoking-attributable mortality among the low- and high-educated in consecutive birth cohorts in 11 European countries. Methods: Register-based mortality data were collected among adults aged 30 to 79 years in 11 European countries between 1971 and 2012. Smoking-attributable deaths were estimated indirectly from lung cancer mortality rates using the Preston-Glei-Wilmoth method. Rate ratios and rate differences among the low and high-educated were estimated and used to estimate the contribution of inequality in smoking-attributable mortality to inequality in total mortality.Results: In most countries, smoking-attributable mortality decreased in consecutive birth cohorts born between 1906 and 1961 among low and high-educated men and high-educated women, but not among low-educated women among whom it increased. Relative educational inequalities in smoking-attributable mortality increased among both men and women with no signs of turning points. Absolute inequalities were stable among men but slightly increased among women. The contribution of inequality in smoking-attributable mortality to inequality in total mortality decreased in consecutive generations among men but increased among women. Conclusions: Generations born during the twentieth century are at different stages of the smoking epidemic. Smoking might become less important as a driver of inequalities in total mortality among men in the future. However, among women, smoking threatens to further widen inequalities in total mortality.
Balanced imitation sustains song culture in zebra finches
Authors: Tchernichovski Ofer , Eisenberg-Edidin Sophie , Jarvis Erich 
Published: September 2020

Abstract
Juvenile songbirds acquire songs by imitation, as humans do speech. Although imitation should drive convergence within a group and divergence through drift between groups, zebra finch songs sustain high diversity within a colony, but only mild variation across colonies. We investigated this phenomenon by analyzing vocal learning statistics in 160 tutor-pupil pairs from a large breeding colony. Song imitation was persistently accurate in some families, but poor in other families. This could not be attributed to genetic differences, as fostered pupils copied their tutors’ vocal sounds as accurately or as poorly as the tutor’s biological pupils. We discovered two effects that explained the finding: first, even in cases of accurate imitation, pupils often recombined imitated syllables to form new units, and, therefore, distributions of syllable types in pupils’ songs were not well correlated with their tutors’; second, rare vocalizations in tutors’ songs became more abundant in their pupils’ songs, and vice versa. Consequently, cultural transmission of tutor songs that were high in acoustic diversity were stronger than those that were low in diversity. We suggest that a frequency dependent balanced imitation of vocal repertoires prevents the extinction of rare song elements and the overabundance of common ones. Within a group it promotes repertoire diversity, while across groups it constrains drift. Together with syllable recombination, balanced imitation sustains cross-generational homeostasis that prevents the collapse of vocal culture into either complete uniformity or chaos.
Cryptotanshinone Breaks ERα-dependent and -independent BCRP Dimerization to Reverse the Multidrug Resistance in Breast Cancer
Authors: Ni Wenting , Fan Hui , Zheng Xiuqin , Xu Fangming , Wu Yuanyuan , Li Xiaoman , Wang Aiyun , Huang Shile , Chen Wenxing , Wang Shijun , Lu Yin 
Published: September 2020

Abstract
Background

Not only a long-term anti-estrogen therapy, but also estrogen receptor-negative breast cancer are generally prone to induce resistance, causing poor prognosis in clinic. Breast cancer resistance protein (BCRP) plays an important role in multidrug resistance. Here it is to elucidate the mechanism that a natural compound cryptotanshinone inhibits BCRP.
Methods

HPLC was for analyzing the special compound concentration and molecular docking assay for the affinity of compound with protein. Non-reducing gradient gel electrophoresis and fluorescence resonance energy transfer (FRET) microscopy imaging were used to detect polymer and stain the membrane protein. Immunofluorescence staining, plasmids transfection, real-time PCR and western blot were also used.
Results

Cryptotanshinone, an anti-estrogen compound was firstly found to inhibit breast cancer resistance protein (BCRP) membrane dimerization to attenuate its transport function. And this process is dependent on estrogen receptor α (ERα) in breast cancer. Furthermore, the resistant breast cancer cells with high BCRP expression are also sensitive to cryptotanshinone because it can bind to BCRP and significantly inhibit membrane dimer of BCRP although they are ERα-negative, suggesting that BCRP expression is essential to cryptotanshinone reversing the resistance; Meanwhile, the combination of cryptotanshinone and chemotherapy drugs could obviously enhance the chemotherapeutic effect.
Conclusion

Cryptotanshinone is a novel natural BCRP inhibitor via blocking the formation of BCRP membrane dimer by an ERα-dependent and -independent way. Cryptotanshinone reverses resistance dependent on BCRP in breast cancer.
Peripheral Microangiopathy in Pre-capillary Pulmonary Hypertension: A Nailfold Video Capillaroscopy Prospective Study
Authors: Arvanitaki Alexandra , Giannakoulas George , Triantafyllidou Eva , Feloukidis Christos , Garyfallos Alexandros , Karvounis Haralambos , Dimitroulas Theodoros 
Published: September 2020

Abstract
Background: Although pulmonary vascular bed has been the main subject of research for many years in pulmonary hypertension (PH), interest has recently started to divert towards the possibility of a co-existing peripheral microangiopathy. The aim of this study was to investigate the presence of peripheral microangiopathy in patients with precapillary pulmonary hypertension by exploring nailfold video-capillaroscopic (NVC) structural changes among various subgroups with precapillary PH and to identify possible associations of NVC characteristics with markers of disease severity. Methods: Α cross-sectional study was performed in 46 consecutive patients with precapillary PH [14 with idiopathic pulmonary arterial hypertension (IPAH), 18 with PAH associated with connective tissue diseases (CTD-PAH) and 14 with chronic thromboembolic pulmonary hypertension (CTEPH)] and 30 healthy controls. NVC quantitative and qualitative parameters were evaluated. Results: Patients with precapillary PH (71.7% were women, mean age 60.8 ± 13.4 years) presented reduced capillary density compared to healthy controls (7.5 ± 1.6 loops/mm vs. 9.7 ± 0.81 loops/mm, p<0.001) and increased capillary loop width (18.8 ± 6.7 μm vs. 11.5 ± 2.3 μm, p<0.001) detected mainly in PAH-CTD. Half of patients presented microhaemorrhages on capillary nailfold, while morphological capillary abnormalities where also detected compared to healthy controls. Log10 (NT-proBNP) was independently associated with capillary density in patients with precapillary PH [r= -0.68, B= -1.9, 95% CI (-3,3, -0.4) p=0.014].Conclusion: Significant NVC microvascular changes were detected in patients with various types of precapillary PH, suggesting an impaired peripheral microcirculation associated with right ventricular remodeling parallel to pulmonary vasculopathy.
Carrier excitation dynamics in black silicon nano pillar arrays
Authors: KALEM SEREF 
Published: September 2020

Abstract
Black silicon has attracted a great deal of interest for its promising photonic applications and exciting physical properties. Several approaches have been used to demonstrate the possibility of producing black silicon with CW light emission, but the investigation of a detailed radiative dynamical properties of the recombination process is still lacking. Here, we present ultrafast radiative recombination phenomena from black silicon consisting of quantum pillars produced by plasma ion etching. An ultrafast blue luminescence component competing with non-radiative recombination at surface defects was identified as no-phonon recombination process. This component involves two decay processes with a peak energy at around 480 nm, which have the fast component of about 10 ps followed by a component of around 50 ps decay time constant. The emission exhibits slow component in red spectral region with time constant ranging from 1.5 to 2.5 ns. When the surface of nano pillars is smoothed, the slow component at around 600 nm is enhanced to the detriment of blue-green emission, increasing the lifetime of carriers within the Si core of the quantum pillars. This process results in a slower sates assuming a 3-component exponential decay as measured by Streak camera. The ultrafast PL decay leads to a transfer of carriers to long-lived defect states as evidenced by a red emission at around 2 eV. The results are interpreted through the presence of quantum confinement at the tip regions of the pillars and surface defects originating from the oxide environment surrounding the nanometer size pillars.
Retinal imaging study diagnoses a case of COVID-19
Authors: Ruiz-Medrano Jorge , Ortiz-Egea José Manuel , Ruiz-Moreno José María 
Published: September 2020

Abstract
Background: Hyper-reflective lesions at the level of ganglion cell (GCL) and inner plexiform retinal layers (IPL) by Optical Coherence Tomography (OCT) and cotton wool spots in the examination of the eye fundus have recently been described as findings in patients with COVID-19 infection.Case report: We report a case of a 42-year-old male anesthetist who treated COVID patients during the previous five weeks and suddenly debuted with a temporal relative scotoma in his left eye (OS); three weeks before, he presented with ageusia for several days. Best corrected visual acuity was 20/20 for OS; no discromatopsy or afferent pupillary defect were present. Visual field was performed, with no significant findings associated to the focal loss of sensitivity referred by the patient. The anterior segment was unremarkable on slit lamp examination in both eyes. Fundus examination of the left eye showed no significant findings. A placoid, hyperreflective band at the level of GCL and IPL was visible in the temporal and nasal side of the fovea on OCT which spared the outer retina, at the time of diagnosis and at one month. A propharyngeal swab test for SARS-CoV-2 RNA, IgG and IgM ELISA determinations were performed. Real-time reverse-transcriptase polymerase chain reaction (RT‐PCR) was negative. ELISA testing and a third rapid antibody detection test performed 7 days after the onset of symptoms were positive.Conclusions: Ocular signs and symptoms in COVID cases are rarely reported, but may be underestimated, especially those that affect the retina and occur in asymptomatic or paucisymptomatic cases. We present the first case of diagnosis of COVID-19 based on retinal ophthalmic examination.
Potential of Photobiomodulation to Induce Differentiation of Adipose- Derived Mesenchymal Stem Cells into Neural Cells
Authors: Van Rensburg Madeleen Jansen , Crous Anine , Abrahamse Heidi 
Published: September 2020

Background:
Given the minimal capacity and sometimes the failure of the mammalian
nervous system to regenerate and repair itself after damage, strategies are required to help enhance
this regenerative process. Adipose-derived Mesenchymal Stem Cells (ADMSCs) are likely candidates
to assist in the recovery process due to their ability to differentiate into neural cells. Successful
implementation of this intervention in a clinical setting would increase the rate of recovery following
traumatic brain injury.

Review:
Various strategies have been attempted to differentiate ADMSCs into neural cells for clinical
use. Such methods have not been entirely successful in the development of functioning specialized
cells for subsequent practical use. Therefore, the implementations of this differentiation technique
in the clinical trial have not been effective. In this article, the potential of differentiating
ADMSCs into neural cells and the various methods employed, including biological induction,
chemical induction and photobiomodulation (PBM) will be discussed, where the combined use of
transducers and PBM for neural differentiation of ADMSCs is also deliberated.

Conclusion:
PBM shows promise as an avenue for effective ADMSCs differentiation into neural
cells and their proliferation. Applying PBM with optimized biological factors and chemical inducers
may prove to be an effective tool for clinical application.
Implementation and Evaluation of a Text Message–Based Addiction Counseling Program (Text4Hope-Addiction Support): Protocol for a Questionnaire Study
Authors: Agyapong Vincent Israel Opoku , Hrabok Marianne , Vuong Wesley , Gusnowski April , Shalaby Reham , Surood Shireen , Greenshaw Andrew J , Aulakh Avininder , Abba-Aji Adam , Singh Mohit 
Published: September 2020

Background
With the emergence of the COVID-19 pandemic, providing counseling to people with drug or alcohol addiction while maintaining physical distance has been challenging. This protocol describes the use of text messaging (as used in the Text4Hope-Addiction Support program) as a convenient, evidence-based, cost-effective, and accessible population-level mental health intervention with high user satisfaction proven in prior research.

Objective
The project goal is to implement a program of daily supportive text messaging (Text4Hope-Addiction Support) to reduce drug or alcohol cravings as well as anxiety and depression, typically associated with alcohol and substance use disorders. The aim of this study is to evaluate the prevalence of cravings, anxiety, and depressive symptoms; demographic correlates of the same; and the outcomes of the Text4Hope-Addiction Support intervention in mitigating cravings, anxiety, and depressive symptoms.

Methods
Self-administered, anonymous, online questionnaires will be used to assess cravings for the primary substance of addiction (Brief Substance Craving Scale), anxiety (Generalized Anxiety Disorder-7), and depressive symptoms (Patient Health Questionnaire-9). Data will be collected at baseline (onset of receiving text messages), program midpoint (6 weeks), and program end (12 weeks).

Results
As of October 2020, data collection is in progress; and it is expected to be completed by fall 2021. Data analysis will include parametric and nonparametric techniques, focusing on primary outcomes (ie, cravings, anxiety, and depressive symptoms) and metrics of use, including the number of subscribers and user satisfaction.

Conclusions
This Text4Hope-Addiction Support project will provide key information regarding the prevalence rates of cravings, anxiety, and depressive symptoms among persons with alcohol and substance use disorders; demographic correlates of cravings, anxiety, and depression; and outcome data related to this scalable population-level intervention. Information from this study will be valuable for addiction care practitioners; it will inform the policy and decision making regarding population-level addiction treatment and support during emergencies.

International Registered Report Identifier (IRRID)
DERR1-10.2196/22047
Carnaval y secularización: disputas en torno a los bailes de máscaras en la ciudad de México en 1831 y 1840
Authors: Sánchez Ulloa Cristóbal Alfonso 
Published: September 2020

<p>Por medio de las discusiones en el ámbito público que los bailes de máscaras de 1831 y 1840 originaron en la ciudad de México, este artículo se acerca a las transformaciones de la sociedad postindependentista. Se aborda el proceso de secularización, en articular las expresiones anticlericales y la paulatina irrupción de actividades profanas en un tiempo otrora de recogimiento, como era la Cuaresma. Se analiza la pugna entre la Iglesia y el Estado por influir en la sociedad, así como el interés de los gobernantes por legitimarse y tener presencia entre los pobladores. Finalmente, se aborda la transformación de las mascaradas en un espectáculo público, encerrado entre las paredes de un teatro, fácil de vigilar y redituable para empresarios y autoridades, así como las opiniones que algunos letrados tuvieron sobre este proceso.</p>