Tag: pubmed

PLoS Pathog. 2021 Apr 9;17(4):e1009501. doi: 10.1371/journal.ppat.1009501. Online ahead of print.

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) protein mediates infection of cells expressing angiotensin-converting enzyme 2 (ACE2). ACE2 is also the viral receptor of SARS-CoV (SARS-CoV-1), a related coronavirus that emerged in 2002-2003. Horseshoe bats (genus Rhinolophus) are presumed to be the original reservoir of both viruses, and a SARS-like coronavirus, RaTG13, closely related to SARS-CoV-2, has been identified in one horseshoe-bat species. Here we characterize the ability of the S-protein receptor-binding domains (RBDs) of SARS-CoV-1, SARS-CoV-2, pangolin coronavirus (PgCoV), RaTG13, and LyRa11, a bat virus similar to SARS-CoV-1, to bind a range of ACE2 orthologs. We observed that the PgCoV RBD bound human ACE2 at least as efficiently as the SARS-CoV-2 RBD, and that both RBDs bound pangolin ACE2 efficiently. We also observed a high level of variability in binding to closely related horseshoe-bat ACE2 orthologs consistent with the heterogeneity of their RBD-binding regions. However five consensus horseshoe-bat ACE2 residues enhanced ACE2 binding to the SARS-CoV-2 RBD and neutralization of SARS-CoV-2 pseudoviruses by an enzymatically inactive immunoadhesin form of human ACE2 (hACE2-NN-Fc). Two of these mutations impaired neutralization of SARS-CoV-1 pseudoviruses. An hACE2-NN-Fc variant bearing all five mutations neutralized both SARS-CoV-2 pseudovirus and infectious virus more efficiently than wild-type hACE2-NN-Fc. These data suggest that SARS-CoV-1 and -2 originate from distinct bat species, and identify a more potently neutralizing form of soluble ACE2.

PMID:33836016 | DOI:10.1371/journal.ppat.1009501

PLoS One. 2021 Apr 9;16(4):e0250015. doi: 10.1371/journal.pone.0250015. eCollection 2021.

ABSTRACT

Hawkes processes are a form of self-exciting process that has been used in numerous applications, including neuroscience, seismology, and terrorism. While these self-exciting processes have a simple formulation, they can model incredibly complex phenomena. Traditionally Hawkes processes are a continuous-time process, however we enable these models to be applied to a wider range of problems by considering a discrete-time variant of Hawkes processes. We illustrate this through the novel coronavirus disease (COVID-19) as a substantive case study. While alternative models, such as compartmental and growth curve models, have been widely applied to the COVID-19 epidemic, the use of discrete-time Hawkes processes allows us to gain alternative insights. This paper evaluates the capability of discrete-time Hawkes processes by modelling daily mortality counts as distinct phases in the COVID-19 outbreak. We first consider the initial stage of exponential growth and the subsequent decline as preventative measures become effective. We then explore subsequent phases with more recent data. Various countries that have been adversely affected by the epidemic are considered, namely, Brazil, China, France, Germany, India, Italy, Spain, Sweden, the United Kingdom and the United States. These countries are all unique concerning the spread of the virus and their corresponding response measures. However, we find that this simple model is useful in accurately capturing the dynamics of the process, despite hidden interactions that are not directly modelled due to their complexity, and differences both within and between countries. The utility of this model is not confined to the current COVID-19 epidemic, rather this model could explain many other complex phenomena. It is of interest to have simple models that adequately describe these complex processes with unknown dynamics. As models become more complex, a simpler representation of the process can be desirable for the sake of parsimony.

PMID:33836020 | DOI:10.1371/journal.pone.0250015

PLoS One. 2021 Apr 9;16(4):e0250037. doi: 10.1371/journal.pone.0250037. eCollection 2021.

ABSTRACT

BACKGROUND: Dietary diversity has continued to receive a global attention among pregnant women as they have been considered susceptible to malnutrition because of their increased nutrient demands. Thus, a variety of foodstuffs in their diet are necessary for ensuring the appropriateness of their nutrient consumptions. This study, therefore assessed the dietary diversity practice and its determinants among pregnant women attending antenatal clinic at Wachemo University Nigist Eleni Mohammed memorial referral hospital, Southern Ethiopia.

METHODS: A hospital-based cross-sectional study was carried out on 303 participants from May 1 to June 15, 2019 using a systematic random sampling technique. Data were entered and analyzed using SPSS (version24.0). Both bivariate and multivariable logistic regression analyses were used to decide the association of each explanatory variable with the outcome variable. Odds ratio with their 95% confidence intervals was calculated to identify the presence and strength of association, and statistical significance was declared at p < 0.05.

RESULTS: The overall prevalence of adequate dietary diversity practices was observed to be 42.6%. The determinants of dietary diversity practice included earning of a monthly income ≥2000 Ethiopian birr (AOR = 1.62; 95%CI:1.19-2.85), maternal educational level (AOR = 2.50; 95% CI: 1.05-6.12), educational status of partner (AOR = 2.45; 95% CI:1.20, 9.57), having a partner who was a government employee (AOR = 4; 95% CI:2.18-7.21), and the receiving of nutritional information (AOR = 1.35; 95% CI: 3.39-6.94).

CONCLUSIONS: The study indicated that the overall consumption of adequate dietary diversity practice was found to be low. Therefore, increasing household income, enhancing nutritional related information, advancing the academic level of both wife and her partner is essential to improve women’s dietary diversity practice.

PMID:33836030 | DOI:10.1371/journal.pone.0250037

Acta Vet Hung. 2021 Apr 8. doi: 10.1556/004.2021.00006. Online ahead of print.

ABSTRACT

Hippocampal changes in epilepsy may manifest as hippocampal atrophy/sclerosis. A recent human study suggests that the demonstration of hippocampal volume loss is more reliable using quantitative evaluation methods. The aim of the present study was to obtain volumetric data in both epileptic and healthy dogs, to compare hippocampal volumes in both groups, and to compare subjective and volumetric assessment. Volumetric measurements of the hippocampi, lateral ventricles and hemispheria were performed in 31 epileptic and 15 control dogs. There was a positive association between the body weight and the hemispheric volume, as well as between the hemispheric volume and the ipsilateral hippocampal volume. There was no significant correlation between age and the volume of any measured brain structures. There was no statistically significant difference between the hippocampal volumes of the control group and the epileptic group. A statistically significant difference between the two groups for hippocampus/hemispherium ratio or hippocampal asymmetric ratio was not identified. An extrapolated hippocampal volume based on body weight was not possible in this study population.

PMID:33835940 | DOI:10.1556/004.2021.00006

Pancreas. 2021 Mar 1;50(3):362-370. doi: 10.1097/MPA.0000000000001780.

ABSTRACT

OBJECTIVES: The postoperative quality of life (QoL) after pancreatic surgery is frequently impaired. The aim of this study was to evaluate the QoL after pancreatic surgery and its influencing risk factors. Furthermore, an age-adjusted comparison with the normal population of Germany was performed.

METHODS: A total of 94 patients were surveyed. The Short Form-36 questionnaire was sent to all patients undergoing pancreatic surgery between 2013 and 2017. All pathologies and types of pancreatic resections were included. Statistical analyses were performed, and an analysis by the Robert Koch-Institute to determine the health-related age-adjusted QoL in Germany served as control group.

RESULTS: Response rate was 29%. Median time of survey was 28 months. As compared with a normative population, QoL after pancreaticoduodenectomy was significantly impaired. Distal pancreatic resection showed no significant differences. Univariate and Lasso analyses showed that the following factors had a negative impact: coronary artery disease, chronic pancreatitis, and open access. Postoperative enzyme supplementation seemed to have a positive impact.

CONCLUSIONS: Pancreatic surgery leads to long-lasting negative effect on QoL. Distal pancreatic resections and laparoscopic access seemed to be the best tolerated. Complications seems to have less impact, whereas maintaining exocrine and endocrine function seems to have a positive effect.

PMID:33835967 | DOI:10.1097/MPA.0000000000001780

PLoS One. 2021 Apr 9;16(4):e0248356. doi: 10.1371/journal.pone.0248356. eCollection 2021.

ABSTRACT

New and more efficient methods to sustainably intensify Aquaculture production are essential to attain the seafood demand for direct human consumption in the near future. Nutrition has been identified as one strategy of early exposure that might affect animal early development and later phenotype. This strategy may have positive consequences in the modulation of fish digestive physiology, which will correlate with higher performance outputs. Thus, improving fish digestive efficiency will lead to higher productivity and lower biogenic emission from aquaculture facilities, minimising the impact on the environment while increasing the biological efficiency. An innovative in ovo nutritional modulation technique based on low-frequency ultrasounds was used to enhance the transport of amino acids across the embryo membranes. An early stimulus with either arginine or glutamine, both involved in gut maturation, was applied in zebrafish (Danio rerio) embryos at 3.5 hours post-fertilization (hpf). At 22 days post-fertilization (dpf), growth performance, digestive enzyme activities and gut microbiota composition were analysed to evaluate the larval nutrition-induced metabolic plasticity and the effects on fish digestive efficiency. Results showed that fish survival was not affected either by the sonophoresis technique or amino acid supplementation. Final dry weight at 22 dpf was statistically higher in larvae from glutamine treatment when compared to the control even with lower trypsin activity, suggesting a higher nutrient digestion capacity, due to a slightly modulation of gut microbiota. Higher arginine supplementation levels should be tested as strategy to enhance growth at later developmental stages. In conclusion, this study demonstrated the efficiency of sonophoresis technique for in ovo nutritional modulation and suggests that in ovo glutamine supplementation might promote growth at later developmental stage through a positive microbiota modulation.

PMID:33835997 | DOI:10.1371/journal.pone.0248356

PLoS One. 2021 Apr 9;16(4):e0249359. doi: 10.1371/journal.pone.0249359. eCollection 2021.

ABSTRACT

A novel penalty for the proportional hazards model under the interval-censored failure time data structure is discussed, with which the subject of variable selection is rarely studied. The penalty comes from an idea to approximate some information criterion, e.g., the BIC or AIC, and the core process is to smooth the ℓ0 norm. Compared with usual regularization methods, the proposed approach is free of heavily time-consuming hyperparameter tuning. The efficiency is further improved by fitting the model and selecting variables in one step. To achieve this, sieve likelihood is introduced, which simultaneously estimates the coefficients and baseline cumulative hazards function. Furthermore, it is shown that the three desired properties for penalties, i.e., continuity, sparsity, and unbiasedness, are all guaranteed. Numerical results show that the proposed sparse estimation method is of great accuracy and efficiency. Finally, the method is used on data of Nigerian children and the key factors that have effects on child mortality are found.

PMID:33836005 | DOI:10.1371/journal.pone.0249359

IEEE J Biomed Health Inform. 2021 Apr 9;PP. doi: 10.1109/JBHI.2021.3072246. Online ahead of print.

ABSTRACT

Cataract causes more than half of all blindness worldwide. The most effective treatment is surgery, where cataract is often replaced by intraocular lens (IOL). Beyond saving vision, toric IOL implantation is becoming increasingly popular to correct corneal astigmatism. It is important to precisely position and align the axis of IOL during surgery to achieve optimal post-operative astigmatism correction. Comparing with conventional manual marking, automated markerless IOL alignment can be faster, more accurate and non-invasive. Here we propose a framework for computer-assisted intraoperative IOL positioning and alignment based on detection and tracking. Firstly, the iris boundary was segmented and the eye center was determined. A statistical sampling method was developed to segment iris and generate training labels, and both conventional algorithms and deep convolutional neural network (CNN) methods were evaluated. Then, regions of interests (ROIs) containing high density of scleral capillaries were used for tracking eye rotations. Both correlation filter and CNN methods were evaluated for tracking. Cumulative errors during long-term tracking were corrected using a reference image. Validation studies against manual labeling using 7 clinical cataract surgical videos demonstrated that the proposed algorithm achieved an average position error around 0.2 mm, an axis alignment error of < 1 degree, and a frame rate of > 25 FPS, and can be potentially used intraoperatively for markerless IOL positioning and alignment during cataract surgery.

PMID:33835929 | DOI:10.1109/JBHI.2021.3072246

JMIR Public Health Surveill. 2021 Apr 2. doi: 10.2196/24623. Online ahead of print.

ABSTRACT

BACKGROUND: Social media has become a ubiquitous part of daily life during the COVID-19 isolation. However, the role of social media use in depression and suicidal ideation of the general public remains unclear. Related empirical studies were limited and reported inconsistent findings. Little is known about the potential underlying mechanisms that may illustrate the relationship between social media use and depression/suicidal ideation during COVID-19.

OBJECTIVE: This study tested the mediation effects of social loneliness and post-traumatic stress (PTSD symptoms) on the relationship between social media use and depressive symptoms/suicidal ideation and the moderation effect of age on the mediation models.

METHODS: We administered a population-based random telephone survey in May and June 2020 when infection control measures were being vigorously implemented in Hong Kong. 1070 adults (658 social media users and 412 non-users) completed the survey. Structural equation modeling (SEM) and multigroup SEM were conducted to test the mediation and moderation effects.

RESULTS: The weighted prevalence of probable depression was 11.6%; 1.6% had suicidal ideation in the past two weeks. Both moderated mediation models of depressive symptoms (χ2(df)=335.34(62), p<.05, CFI=.94, NNFI=.92, RMSEA=.06) and suicidal ideation (χ2(df)=50.80(34), p<.05, CFI=.99, NNFI=.99, RMSEA=.02) showed acceptable model fit. There was a significantly negative direct effect of social media use on depressive symptoms among older people (β=-.07, p=.04) but not among younger people (β=.04, p=.55). The indirect effect via PTSD symptoms was significantly positive among both younger (β=.09, p=.02) and older people (β=.10, p=.01). The indirect effect via social loneliness was significant among older people (β=-.01, p=.04) but not among younger people (β=.01, p=.31). The direct effect of social media use on suicidal ideation was not statistically significant in both age groups (p>.05). The indirect effects via PTSD symptoms were statistically significant among younger (β=.02, p=.04) and older people (β=.03, p=.01). Social loneliness was not a significant mediator between social media use and suicidal ideation among neither younger nor older people (p>.05).

CONCLUSIONS: Social media may be a ‘double-edged sword’ for psycho-social well-being during COVID-19 and its roles vary across age groups. The mediators identified in this study can be addressed by psychological interventions to prevent severe mental health problems during and after COVID-19.

PMID:33835937 | DOI:10.2196/24623

AIDS Patient Care STDS. 2021 Apr;35(4):116-125. doi: 10.1089/apc.2020.0258.

ABSTRACT

Human immunodeficiency virus (HIV) infection is still a major cause of death in Thais and new cases of infection are still emerging among the key population comprising men who have sex with men (MSM), sex workers and their clients, and transgender women (TGW) and people who inject drugs. The objective of this study was to compare the incidence of HIV infection between MSM and TGW who were tested at stand-alone and mobile HIV voluntary counseling and testing (VCT) centers and to identify factors associated with HIV-positive individuals from the two services. We conducted an observational study using MSM and TGW individuals with unknown HIV status from the databases at a stand-alone center and a mobile VCT belonging to the MPlus in Chiang Mai province, Thailand. Factors associated with HIV-positive status were identified using logistic regression model. HIV VCT data were obtained for 6971 individuals at both MPlus center and mobile care unit. Among 3033 and 3938 clients tested at each facility, respectively, 168 (5.6%) and 101 (2.6%) clients were HIV positive. Individuals tested at the stand-alone centers were at a 1.91-fold higher risk of being HIV positive compared with those tested at the mobile VCT unit. Individuals who were 20-24 or >24 years old, sex workers, or sexually transmitted infection positive were more likely to be HIV positive. Our results show the beneficial effect of mobile HIV VCT facilities that enable testing of more of the at-risk population. Developing mobile VCT activities that attract a particular target population is needed to be able to reach the 90-90-90 goals. This study was approved by the Ethics Committee of the Faculty of Medicine, Chiang Mai University (0BG-2562-06418).

PMID:33835852 | DOI:10.1089/apc.2020.0258