scholarly journals Comparison of Plaque Size, Thermal Stability, and Replication Rate among SARS-CoV-2 Variants of Concern

2021 ◽  
Author(s):  
Gi Uk Jeong ◽  
Gun Young Yoon ◽  
Hyun Woo Moon ◽  
Wooseong Lee ◽  
Insu Hwang ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Plaque Size ◽  
Effective Management ◽  
Replication Rate ◽  
Gamma Delta ◽  
Prolonged Incubation ◽  
Physiological Temperature ◽  
Novel Variants ◽  
The Mean ◽  
Different Characteristics

SARS-CoV-2, like other RNA viruses, has a propensity for genetic evolution owing to the low fidelity of its viral polymerase. This evolution results in the emergence of novel variants with different characteristics than their ancestral strain. Several recent reports have described a series of novel SARS-CoV-2 variants. Some of these have been identified as variants of concern (VOCs), including alpha (B.1.1.7, Clade GRY), beta (B.1.351, Clade GH), gamma (P.1, Clade GR), and delta (B.1.617.2, Clade G). VOCs are likely to have some effect on transmissibility, antibody evasion, and changes in therapeutic or vaccine effectiveness. However, the physiological and virological understanding of these variants remains poor. We demonstrated that these four VOCs exhibited differences in plaque size, thermal stability at physiological temperature, and replication rates. The mean plaque size of beta was the largest, followed by those of gamma, delta, and alpha. Thermal stability, evaluated by measuring infectivity and half-life after prolonged incubation at physiological temperature, was correlated with plaque size in all variants except alpha. However, despite its relatively high thermal stability, alpha's small plaque size resulted in lower replication rates and fewer progeny viruses. Our findings may inform further virological studies of SARS-CoV-2 variant characteristics, VOCs, and variants of interest. These studies are important for the effective management of the COVID-19 pandemic.

scholarly journals Comparison of Plaque Size, Thermal Stability, and Replication Rate among SARS-CoV-2 Variants of Concern

Viruses ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 55
Author(s):  
Gi Uk Jeong ◽  
Gun Young Yoon ◽  
Hyun Woo Moon ◽  
Wooseong Lee ◽  
Insu Hwang ◽  
...  
Keyword(s):  
Thermal Stability ◽  
High Thermal Stability ◽  
Plaque Size ◽  
Effective Management ◽  
Replication Rate ◽  
Gamma Delta ◽  
Small Plaque ◽  
Prolonged Incubation ◽  
Physiological Temperature ◽  
The Mean

SARS-CoV-2, like other RNA viruses, has a propensity for genetic evolution owing to the low fidelity of its viral polymerase. Several recent reports have described a series of novel SARS-CoV-2 variants. Some of these have been identified as variants of concern (VOCs), including alpha (B.1.1.7, Clade GRY), beta (B.1.351, Clade GH), gamma (P.1, Clade GR), and delta (B.1.617.2, Clade G). VOCs are likely to have some effect on transmissibility, antibody evasion, and changes in therapeutic or vaccine effectiveness. However, the physiological and virological understanding of these variants remains poor. We demonstrated that these four VOCs exhibited differences in plaque size, thermal stability at physiological temperature, and replication rates. The mean plaque size of beta was the largest, followed by those of gamma, delta, and alpha. Thermal stability, evaluated by measuring infectivity and half-life after prolonged incubation at physiological temperature, was correlated with plaque size in all variants except alpha. However, despite its relatively high thermal stability, alpha’s small plaque size resulted in lower replication rates and fewer progeny viruses. Our findings may inform further virological studies of SARS-CoV-2 variant characteristics, VOCs, and variants of interest. These studies are important for the effective management of the COVID-19 pandemic.

scholarly journals Zooplankton community dynamics and environmental factors in Lake Ozeros (Greece)

2013 ◽  
Vol 14 (3) ◽  
pp. 32 ◽  
Author(s):  
E. CHALKIA ◽  
G. KEHAYIAS
Keyword(s):  
Community Dynamics ◽  
Zooplankton Community ◽  
Trophic State Index ◽  
Zooplankton Abundance ◽  
The Novel ◽  
Effective Management ◽  
Eutrophic Lakes ◽  
State Index ◽  
The Mean ◽  
One Year

A one year investigation of the zooplankton community composition and dynamics in Lake Οzeros (western Greece) revealed 25 invertebrate species (16 rotifers, three copepods, five cladocerans and one mollusc larva). The mean zooplankton abundance fluctuated between 59.4 to 818 ind l-1, having maximum values in spring. The species composition and seasonal variation do not differentiate Lake Ozeros from the nearby lakes. The presence of the dominant calanoid copepod Eudiaptomus drieschi and some of the rotifer species recorded are characteristics of either oligo- or eutrophic lakes. According to the trophic state index (TSI) Lake Ozeros is a meso-eutrophic ecosystem, in which the eutrophic character was possibly the result of the high charge with phosphorus (being raised by 28.9 % in comparison to previous decades), which came into the lake via the surrounding agricultural cultivations and mainly the pig-raising activities. In contrast, the concentrations of ΝΟ3, ΝΟ2 and NH4 have considerably decreased possibly due to the termination of the tobacco cultivations around the lake during the last years. The novel information on the abiotic and especially the biotic elements of Lake Ozeros provided by the present study can contribute to the effective management of this aquatic ecosystem in the future.

scholarly journals Acoustic Target Strength of the Endangered Chinese Sturgeon (Acipenser sinensis) by Ex Situ Measurements and Theoretical Calculations

2018 ◽  
Vol 8 (12) ◽  
pp. 2554 ◽  
Author(s):  
Hui Zhang ◽  
Junyi Li ◽  
Chongrui Wang ◽  
Chengyou Wang ◽  
Jinming Wu ◽  
...  
Keyword(s):  
Theoretical Calculations ◽  
Breeding Population ◽  
Ex Situ ◽  
Target Strength ◽  
Effective Management ◽  
Chinese Sturgeon ◽  
Acipenser Sinensis ◽  
Acoustic Target ◽  
The Mean ◽  
Db Difference

The Chinese sturgeon, Acipenser sinensis, is a large anadromous and highly endangered protected species. The assessment of its breeding population in the Yangtze River is critically important for effective management and population preservation. Currently, hydroacoustic methods have been widely used to study the adult sturgeons in the river, whereas the acoustic target strength (TS) characteristics of the species have not been studied. In this study, the TS of Chinese sturgeon was carefully evaluated both by ex situ measurements and theoretical calculations. Six Chinese sturgeons (Body Length (BL): 74.0−92.6 cm) were measured by a 199 kHz split echosounder in a 10-m deep net cage. The computed tomography of a Chinese sturgeon (BL: 110.0 cm) was conducted and the Kirchhoff ray mode (KRM) method was used to estimate the theoretical TS. As a result, the mean ex situ TS range of the six specimens was from −26.9 to −31.4 dB, which was very close to the KRM estimation (~1 dB difference). Then, the KRM method was used to predict the TS of Chinese sturgeon as a function of BL in six frequencies commonly used in freshwater environments and to estimate the TS of a representative adult Chinese sturgeon (250 cm) as a function of frequency and tilt angle. This study can provide a good basis for future hydroacoustic studies on the critically endangered Chinese sturgeon.

scholarly journals 457. Cutibacterium (Propionibacterium) acnes Infection Rate and Optimization of Surgical Culture Duration

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S224-S225
Author(s):  
Carlos Christian Cueva ◽  
Robert Odrobina ◽  
Jakrapun Pupaibool ◽  
Mark Fisher
Keyword(s):  
Salt Lake ◽  
Normal Skin ◽  
Salt Lake City ◽  
Causative Organism ◽  
Prolonged Incubation ◽  
Clinical Criteria ◽  
Surgical Infections ◽  
Cutibacterium Acnes ◽  
Culture Duration ◽  
The Mean

Abstract Background Cutibacterium acnes is part of the normal skin and gastrointestinal tract flora that is increasingly recognized as a causative organism of surgical infections. Distinguishing between infection and contamination is difficult. The standard culture duration for C. acnes has not been determined. As a slow-growing organism, a prolonged incubation of 10–14 days is adopted in many laboratories. Ideally, only samples with high pretest probability for infection should be worked up this way, otherwise resources are overutilized with likely no benefits and potential harms to patients. We conduct a study to assess the optimal incubation duration for C. acnes. Methods We retrospectively reviewed microbiologic and clinical data of patients who underwent surgical procedures at the Veterans Affairs (VA) Hospital and the University of Utah Hospital in Salt Lake City, Utah, between 2015 and 2018 for which prolonged incubation of surgical samples was requested. Samples that grew C. acnes were divided into three groups (infection, contaminant, indeterminate) based on the quantity of growth and the number of positive samples (Figure 1). Samples in the “indeterminate” group were re-classified into the other two groups based on clinical criteria (Figure 2). Time to culture positivity (TTP) was calculated for each group. Results 741 patients contributed to a total of 909 surgical cases. There were 2,401 samples collected resulting in 4,408 bacterial cultures. C. acnes grew in 131 cases (14.41%). Fifty-five cases (44%) fulfilled the criteria for true infections and 70 cases (56%) were contaminants. 6 cases were lost to follow-up. The mean TTP of the infection and the contamination groups were 5.60 + 0.76 days and 8.67 + 0.81 days, respectively. The TTP of C. acnes from specimens of true surgical infections was significantly shorter than that of contaminants by the mean of 3.07 days (95% CI: -4.22 to -1.92); P < 0.001. Conclusion Using our microbiological and clinical criteria to differentiate infections and contaminations, this study provides evidence that surgical sample cultures should be held no longer than 7 days to limit the effect of contaminated C. acnes on cultures and reduce unnecessary antimicrobial use. Disclosures All authors: No reported disclosures.

scholarly journals Clinical characteristics of acute respiratory distress syndrome survived patients at a tertiary hospital in Jakarta

2017 ◽  
Vol 26 (1) ◽  
pp. 35-9
Author(s):  
Zulkifli Amin ◽  
Fitriana N. Rahmawati ◽  
Chrispian O. Mamudi ◽  
Astrid P. Amanda
Keyword(s):  
Developing Countries ◽  
Descriptive Analysis ◽  
Good Deal ◽  
Tertiary Hospital ◽  
Clinical Profile ◽  
Primary Data ◽  
Apache Ii Score ◽  
Common Causes ◽  
The Mean ◽  
Different Characteristics

Background: While a good deal of research on characteristic the different characteristics between surviving and dying patient with ARDS has been conducted globally, such research is scarce in developing countries. This study aimed to obtain clinical profile of ARDS survivors during hospitalization.Methods: This was a prospective, observational study conducted at a tertiary hospital in Jakarta from October 2015 to April 2016. Primary data was collected from ARDS patients based on Berlin Definition admitted to emergency room, ICU, HCU, ICCU, and all other wards. The patients were followed until they discharged. We only included survivors on the analysis. Descriptive analysis was done using SPSS 21.0.Results: A total of 43 patients were survived during study period. The majority were below 65 years of age (69.8%) and were male (53.5%). ARDS was mainly mild in severity (62.8%) and early onset (55.8%). Sepsis was the most common causes of ARDS (97.7%). Most of the patients had comorbidities (74.4%). Majority of the patients had APACHE II score <20 (77.3%) with mean 15.6±4.8. The mean of albumin was 2.9±0.6 and the median of procalcitonin was 3 (0.1-252.3.Conclusion: The clinical profile of ARDS survivors in our study were mostly similar with other studies conducted in developed and other developing countries.

scholarly journals Management of bleeding associated with radiofrequency ablation of benign thyroid nodules

2020 ◽  
Vol 48 (8) ◽  
pp. 030006052093752
Author(s):  
Kunpeng Hu ◽  
Yufan Lian ◽  
Jinfen Wang ◽  
Wenchao Li ◽  
Zhicheng Yao ◽  
...  
Keyword(s):  
Radiofrequency Ablation ◽  
Thyroid Nodules ◽  
Effective Management ◽  
Voice Change ◽  
Life Threatening ◽  
The Mean ◽  
Benign Thyroid Nodules ◽  
Benign Thyroid ◽  
Clinical Strategy

Objective This study was performed to explore the effective management of bleeding associated with radiofrequency ablation (RFA) of benign thyroid nodules. Methods Thirty-five patients with benign thyroid nodules who were treated with ultrasound-guided RFA from July 2015 to December 2016 at the Third Affiliated Hospital of Sun Yat-sen University were retrospectively reviewed. The technique efficacy, bleeding, and other complications were assessed during the follow-up period. Results The mean technique efficacy was 55.6%±22.8% at 1 month and 24.1%±17.1% at 6 months after the procedure. One case of an intranodular haematoma and two cases of voice change (>1 month) were observed. All patients recovered with corresponding treatment. Conclusion Although the incidence of haemorrhage is low, serious haematomas are life-threatening. Therefore, having a comprehensive understanding of the potential complications, an accurate clinical strategy, and adequate technical skills may prevent or help to properly manage these complications.

Wind Speed Change and Influence on Wind Energy in Recent 50 Years over Hexi Corridor

2014 ◽  
Vol 1070-1072 ◽  
pp. 284-290
Author(s):  
Yao Zong Zhang ◽  
Bo Zhang ◽  
Yan Yan Liu
Keyword(s):  
Wind Speed ◽  
Wind Energy ◽  
Nonparametric Test ◽  
Test Methods ◽  
Hexi Corridor ◽  
Mean Wind Speed ◽  
Seasonal Wind ◽  
Speed Change ◽  
The Mean ◽  
Different Characteristics

Based on wind speed data of 13 meteorological stations in 1958-2012,Mann-Kendall nonparametric test methods was been used to study on wind speed changes in Hexi Corridor.Spatial and temporal characteristics of seasonal and monthly wind speed changes was examined. (1) The maximum wind speed appeared in the higher elevations of study area, such as Wushaoling and Mazongshan station. From east to west mean wind speed increased in Hexi Corridor.For nearly 50 years wind speed had showed decreasing trend. (2)In each season Spring with an maximum mean wind speed was 3.4m/s,the Summer mean wind speed was 2.9 m/s,Autumn mean wind speed was 2.6 m/s,the mean Winter wind speed was 2.8m/s.The seasonal wind speed mainly had decline trend, each station.has different characteristics trends (3) Mean wind speed in each month was greater than 2.5m/s,maximum monthly wind speed appeared in April was 3.5m/s,the minimum wind speed appeared in the September-October was 2.53m/s,the wind speed in March,April and May was greater than the November month,December,January.In addition to Mazongshan and Wushaoling,other station monthly wind speed showed a decreasing trend.Monthly mean wind speed in Jiuquan,Dingxin and Zhangye was slow decreasing trend.Anxi,Yumen wind decreasing trend were more obvious.(4)Wind decreasing trend will have a significant impact on wind energy, wind speed changes and wind energy should be evaluated in the future.

TRIIODOTHYRONINE BINDING TO LYMPHOCYTES FROM EUTHYROID SUBJECTS AND A PATIENT WITH PERIPHERAL RESISTANCE TO THYROID HORMONE

1976 ◽  
Vol 83 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Kristian Liewendahl
Keyword(s):  
Thyroid Hormone ◽  
Binding Sites ◽  
Binding Capacity ◽  
Human Lymphocytes ◽  
Peripheral Resistance ◽  
Subsequent Treatment ◽  
Affinity Constant ◽  
Prolonged Incubation ◽  
Resistance To Thyroid Hormone ◽  
The Mean

ABSTRACT Triiodothyronine (T3) binding to Ficoll-Isopaque purified human lymphocytes was studied. During incubation of lymphocytes with [125I]T3 in a calcium-free medium at 37°C, maximal uptake of T3 in nuclei occurred after 2 h and declined after prolonged incubation. Incubation of lymphocytes with T3 concentrations ranging from 1 × 10−11 to 1 × 10−9 mol/l and subsequent treatment with Triton X-100 to strip off [125I]T3 bound with low affinity was used for the estimation of affinity and capacity of nuclear T3 binding sites. The mean equilibrium affinity constant (Ka) estimated with the Scatchard method in 11 euthyroid healthy subjects was 4.5 × 109 1/mol, and the mean maximal binding capacity 25 × 10−15 mol/100 μg DNA. In a female patient with peripheral resistance to thyroid hormone action, the estimated Ka was 3.5 × 109 1/mol and the number of T3 binding sites 37 × 10−15 mol/100 μg DNA. Although not statistically different from the mean value in euthyroid subjects, this Ka value was outside the range of control values observed and was considered presumptive evidence that the nuclear T3 receptors in this patient have abnormally low affinity for its ligand. The nuclear T3 binding capacity in this patient was significantly increased.

Enhanced Thermal Stability and Mechanical Properties of Ultrafine-Grained Aluminum Alloy

2010 ◽  
Vol 667-669 ◽  
pp. 331-336 ◽  
Author(s):  
Rinat K. Islamgaliev ◽  
Marina A. Nikitina ◽  
Aidar F. Kamalov
Keyword(s):  
Thermal Stability ◽  
Aluminum Alloy ◽  
Volume Fraction ◽  
High Pressure Torsion ◽  
Coarse Grained ◽  
Dynamic Precipitation ◽  
Ultrafine Grained ◽  
The Mean ◽  
Fatigue Endurance ◽  
Thermal Stability Of

The paper reports on microstructure, strength and fatigue of ultrafine-grained (UFG) samples of the Al-Cu-Mg-Si aluminum alloy processed by high pressure torsion (HPT) at various temperatures. Application of the HPT treatment led to strong grain refinement, as well as to a raise of the mean-root square strains and dynamic precipitation. In case of optimal HPT treatment the UFG samples have demonstrated the enhanced thermal stability, an increase in ultimate tensile strength in 2.5 times and enhancement in fatigue endurance limit by 20 % in comparison with coarse-grained alloy subjected to standard treatment. It is shown that the regime of the HPT treatment governs the volume fraction of precipitates and segregations, thereby affecting a grain size and thermal stability of ultrafine-grained structure.

scholarly journals Vaccine-breakthrough infection by the SARS-CoV-2 Omicron variant elicits broadly cross-reactive immune responses

2021 ◽  
Author(s):  
Runhong Zhou ◽  
Kelvin Kai-Wang To ◽  
Qiaoli Peng ◽  
Jacky Man-Chun Chan ◽  
Haode Huang ◽  
...  
Keyword(s):  
Immune Responses ◽  
Neutralizing Antibodies ◽  
Preventive Strategies ◽  
Gamma Delta ◽  
Breakthrough Infection ◽  
Host Immune Responses ◽  
Cell Responses ◽  
Booster Vaccine ◽  
Ic50 Values ◽  
The Mean

Highly transmissible SARS-CoV-2 Omicron variant has posted a new crisis for COVID-19 pandemic control. Within a month, Omicron is dominating over Delta variant in several countries probably due to immune evasion. It remains unclear whether vaccine-induced memory responses can be recalled by Omicron infection. Here, we investigated host immune responses in the first vaccine-breakthrough case of Omicron infection in Hong Kong. We found that the breakthrough infection rapidly recruited potent cross-reactive broad neutralizing antibodies (bNAbs) against current VOCs, including Alpha, Beta, Gamma, Delta and Omicron, from unmeasurable IC50 values to mean 1:2929 at around 9-12 days, which were higher than the mean peak IC50 values of BioNTech-vaccinees. Cross-reactive spike- and nucleocapsid-specific CD4 and CD8 T cell responses were detected. Similar results were also obtained in the second vaccine-breakthrough case of Omicron infection. Our preliminary findings may have timely implications to booster vaccine optimization and preventive strategies of pandemic control.

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