Quantitative detection of human- and canine-associated Bacteroides genetic markers from an urban coastal lagoon

Abstract The contamination of water catchments by nonpoint source faecal pollution is a major issue affecting the microbial quality of receiving waters and is associated with the occurrence of a range of enteric illnesses in humans. The potential sources of faecal pollution in surface waters are diverse, including urban sewage leaks, surface runoff and wildlife contamination originating from a range of hosts. The major contributing hosts require identification to allow targeted management of this public health concern. In this study, two high-performing Microbial Source Tracking (MST) assays, HF183/Bac242 and BacCan-UCDmodif, were used for their ability to detect host-specific Bacteroides 16Sr RNA markers for faecal pollution in a 12-month study on an urban coastal lagoon in Sydney, Australia. The lagoon was found to contain year-round high numbers of human and canine faecal markers, as well as faecal indicator bacteria counts, suggesting considerable human and animal faecal pollution. The high sensitivity and specificity of the HF183/Bac242 and BacCan-UCDmodif assays, together with the manageable levels of PCR inhibition and high level DNA extraction efficiency obtained from lagoon water samples make these markers candidates for inclusion in an MST ‘toolbox’ for investigating host origins of faecal pollution in urban surface waters.

Download Full-text

Integrating high-performing electrochemical transducers in lateral flow assay

Analytical and Bioanalytical Chemistry ◽

10.1007/s00216-021-03301-y ◽

2021 ◽

Author(s):

Antonia Perju ◽

Nongnoot Wongkaew

Keyword(s):

High Performance ◽

Point Of Care ◽

Low Cost ◽

High Sensitivity ◽

Lateral Flow ◽

Analytical Performance ◽

Label Free ◽

High Performing ◽

Lateral Flow Assays ◽

Electrochemical Transducers

AbstractLateral flow assays (LFAs) are the best-performing and best-known point-of-care tests worldwide. Over the last decade, they have experienced an increasing interest by researchers towards improving their analytical performance while maintaining their robust assay platform. Commercially, visual and optical detection strategies dominate, but it is especially the research on integrating electrochemical (EC) approaches that may have a chance to significantly improve an LFA’s performance that is needed in order to detect analytes reliably at lower concentrations than currently possible. In fact, EC-LFAs offer advantages in terms of quantitative determination, low-cost, high sensitivity, and even simple, label-free strategies. Here, the various configurations of EC-LFAs published are summarized and critically evaluated. In short, most of them rely on applying conventional transducers, e.g., screen-printed electrode, to ensure reliability of the assay, and additional advances are afforded by the beneficial features of nanomaterials. It is predicted that these will be further implemented in EC-LFAs as high-performance transducers. Considering the low cost of point-of-care devices, it becomes even more important to also identify strategies that efficiently integrate nanomaterials into EC-LFAs in a high-throughput manner while maintaining their favorable analytical performance.

Download Full-text

Rapid, highly sensitive and quantitative detection of interleukin 6 based on SERS magnetic immunoassay

Analytical Methods ◽

10.1039/d0ay02304c ◽

2021 ◽

Vol 13 (15) ◽

pp. 1823-1831

Author(s):

Xiaomei Wang ◽

Li Ma ◽

Shijiao Sun ◽

Tingwei Liu ◽

Hao Zhou ◽

...

Keyword(s):

Interleukin 6 ◽

High Sensitivity ◽

Quantitative Detection ◽

Detection Time ◽

Highly Sensitive ◽

Sandwich Method

We have developed a SERS magnetic immunoassay method based on the principle of sandwich method for rapid and quantitative detection of IL-6. The developed SERS method has the advantages of high sensitivity and detection time is only 15 min.

Download Full-text

WGS of Commensal Neisseria Reveals Acquisition of a New Ribosomal Protection Protein (MsrD) as a Possible Explanation for High Level Azithromycin Resistance in Belgium

Pathogens ◽

10.3390/pathogens10030384 ◽

2021 ◽

Vol 10 (3) ◽

pp. 384

Author(s):

Tessa de Block ◽

Jolein Gyonne Elise Laumen ◽

Christophe Van Dijck ◽

Said Abdellati ◽

Irith De Baetselier ◽

...

Keyword(s):

Integration Site ◽

Bacterial Species ◽

Resistance Mechanism ◽

Health Concern ◽

Sex With Men ◽

High Level ◽

Ribosomal Protection Protein ◽

Commensal Neisseria ◽

Level Resistance ◽

Ribosomal Protection

In this study, we characterized all oropharyngeal and anorectal isolates of Neisseria spp. in a cohort of men who have sex with men. This resulted in a panel of pathogenic Neisseria (N. gonorrhoeae [n = 5] and N. meningitidis [n = 5]) and nonpathogenic Neisseria (N. subflava [n = 11], N. mucosa [n = 3] and N. oralis [n = 2]). A high proportion of strains in this panel were resistant to azithromycin (18/26) and ceftriaxone (3/26). Whole genome sequencing (WGS) of these strains identified numerous mutations that are known to confer reduced susceptibility to azithromycin and ceftriaxone in N. gonorrhoeae. The presence or absence of these known mutations did not explain the high level resistance to azithromycin (>256 mg/L) in the nonpathogenic isolates (8/16). After screening for antimicrobial resistance (AMR) genes, we found a ribosomal protection protein, Msr(D), in these highly azithromycin resistant nonpathogenic strains. The complete integration site originated from Streptococcus pneumoniae and is associated with high level resistance to azithromycin in many other bacterial species. This novel AMR resistance mechanism to azithromycin in nonpathogenic Neisseria could be a public health concern if it were to be transmitted to pathogenic Neisseria. This study demonstrates the utility of WGS-based surveillance of nonpathogenic Neisseria.

Download Full-text

60–700 K CTAT and PTAT Temperature Sensors with 4H-SiC Schottky Diodes

Sensors ◽

10.3390/s21030942 ◽

2021 ◽

Vol 21 (3) ◽

pp. 942

Author(s):

Razvan Pascu ◽

Gheorghe Pristavu ◽

Gheorghe Brezeanu ◽

Florin Draghici ◽

Philippe Godignon ◽

...

Keyword(s):

Low Cost ◽

Schottky Diodes ◽

Schottky Contact ◽

High Sensitivity ◽

Xrd Analysis ◽

Absolute Temperature ◽

Lower Sensitivity ◽

Readout Circuit ◽

Sensing Element ◽

High Performing

A SiC Schottky dual-diode temperature-sensing element, suitable for both complementary variation of VF with absolute temperature (CTAT) and differential proportional to absolute temperature (PTAT) sensors, is demonstrated over 60–700 K, currently the widest range reported. The structure’s layout places the two identical diodes in close, symmetrical proximity. A stable and high-barrier Schottky contact based on Ni, annealed at 750 °C, is used. XRD analysis evinced the even distribution of Ni2Si over the entire Schottky contact area. Forward measurements in the 60–700 K range indicate nearly identical characteristics for the dual-diodes, with only minor inhomogeneity. Our parallel diode (p-diode) model is used to parameterize experimental curves and evaluate sensing performances over this far-reaching domain. High sensitivity, upwards of 2.32 mV/K, is obtained, with satisfactory linearity (R2 reaching 99.80%) for the CTAT sensor, even down to 60 K. The PTAT differential version boasts increased linearity, up to 99.95%. The lower sensitivity is, in this case, compensated by using a high-performing, low-cost readout circuit, leading to a peak 14.91 mV/K, without influencing linearity.

Download Full-text

Influence of Irrational Beliefs and Sensitivity to a Person on Future Psychology Students’ Propensity to Coercion or Nonviolence

Sibirskiy psikhologicheskiy zhurnal ◽

10.17223/17267081/81/7 ◽

2021 ◽

pp. 143-165

Author(s):

V.G. Maralov ◽

◽

V.A. Sitarov ◽

Keyword(s):

Irrational Beliefs ◽

High Sensitivity ◽

Daily Practice ◽

Psychology Students ◽

State Universities ◽

Low Level ◽

Level Of Understanding ◽

Low Sensitivity ◽

High Level ◽

Dependent Type

The relevance of the problem is due to the importance of identifying factors that determine the propensity of students to coercion or nonviolence, creating psychological and pedagogical conditions for the formation of the socionomic sphere of nonviolent competencies for future specialists at universities. The theoretical basis of the study was the position of nonviolence as a daily practice of interaction, by which we understand the ability of a person to choose from a number of possible alternatives that carry the least charge of coercion. The aim of the work was to study the influence of irrational beliefs and sensitivity to a person (interest, empathy, understanding and assistance) on the students’ tendency to coercion, manipulation, non-violence and non-interference in the processes of interaction with people. The hypothesis was tested that the tendency of students to coercion, manipulation, and noninterference will be due to expressed irrational beliefs and low level of sensitivity to a person and the tendency to non-violence will be explained by the absence of irrational beliefs and a high level of sensitivity to a person. The study involved 125 students of pedagogical and psychological faculties of the Moscow Humanitarian and Cherepovets State universities. The authors used questionnaires to identify the positions of interaction among students and sensitivity to a person, as well as a list of irrational beliefs proposed by A. Beck and A. Freeman. It is established that the tendency to both coercion and manipulation are determined by the beliefs of anti-social type and low sensitivity to the person. The tendency to manipulate the narcissistic beliefs, high interest in people and understanding them, at the same time the tendency to non-violence and non-interference are determined by beliefs of avoidant and dependent types with a low level of understanding people. And a tendency to non-interference is determined by beliefs of dependent type with unexpressed orientation on helping. The tendency to nonviolence is determined by the high sensitivity to a person and the absence of irrational beliefs of antisocial, passive-aggressive and narcissistic types. As a result, the conclusion is made about the need to form purposefully the ability to nonviolent interaction among students, which should include the work on awareness and overcoming irrational beliefs and the development of sensitivity to a person. The obtained results can be used in practical work with students on the formation of their nonviolent competencies.

Download Full-text

A GFP Reporter MR766-Based Flow Cytometry Neutralization Test for Rapid Detection of Zika Virus-Neutralizing Antibodies in Serum Specimens

Vaccines ◽

10.3390/vaccines7030066 ◽

2019 ◽

Vol 7 (3) ◽

pp. 66 ◽

Cited By ~ 5

Author(s):

Frumence ◽

Viranaicken ◽

Gadea ◽

Desprès

Keyword(s):

Flow Cytometry ◽

Zika Virus ◽

Neutralizing Antibodies ◽

Neutralization Test ◽

Health Concern ◽

Structural Protein ◽

Adult Mice ◽

Gfp Reporter ◽

Infected Cells ◽

High Level

Zika virus (ZIKV) is an emerging arthropod-borne virus of major public health concern. ZIKV infection is responsible for congenital Zika disease and other neurological defects. Antibody-mediated virus neutralization is an essential component of protective antiviral immunity against ZIKV. In the present study, we assessed whether our GFP reporter ZIKV derived from African viral strain MR766 could be useful for the development of a flow cytometry neutralization test (FNT), as an alternative to the conventional plaque-reduction neutralization test (PRNT). To improve the efficacy of GFP-expressing MR766, we selected virus variant MR766GFP showing a high level of GFP signal in infected cells. A MR766GFP-based FNT was assayed with immune sera from adult mice that received ZIKBeHMR-2. The chimeric ZIKV clone ZIKBeHMR-2 comprises the structural protein region of epidemic strain BeH819015 into MR766 backbone. We reported that adult mice inoculated with ZIKBeHMR-2 developed high levels of neutralizing anti-ZIKV antibodies. Comparative analysis between MR766GFP-based FNT and conventional PRNT was performed using mouse anti-ZIKBeHMR-2 immune sera. Indistinguishable neutralization patterns were observed when compared with PRNT50 and FNT50. We consider that the newly developed MR766GFP-based FNT is a valid format for measuring ZIKV-neutralizing antibodies in serum specimens.

Download Full-text

Dramatically Enhancing the Sensitivity of Immunoassay for Ochratoxin A Detection by Cascade-Amplifying Enzyme Loading

Toxins ◽

10.3390/toxins13110781 ◽

2021 ◽

Vol 13 (11) ◽

pp. 781

Author(s):

Zhuolin Song ◽

Lin Feng ◽

Yuankui Leng ◽

Mingzhu Huang ◽

Hao Fang ◽

...

Keyword(s):

Ochratoxin A ◽

Limit Of Detection ◽

High Sensitivity ◽

Cross Reaction ◽

Molar Ratio ◽

Quantitative Detection ◽

Enzyme Linked Immunosorbent Assay ◽

Enzyme Loading ◽

M13 Bacteriophage ◽

Mimic Peptide

Enzyme-linked immunosorbent assay (ELISA) is widely used in the routine screening of mycotoxin contamination in various agricultural and food products. Herein, a cascade-amplifying system was introduced to dramatically promote the sensitivity of an immunoassay for ochratoxin A (OTA) detection. Specifically, a biotinylated M13 bacteriophage was introduced as a biofunctional competing antigen, in which a seven-peptide OTA mimotope fused on the p3 protein of M13 was used to specifically recognize an anti-OTA monoclonal antibody, and the biotin molecules modified on capsid p8 proteins were used in loading numerous streptavidin-labeled polymeric horseradish peroxidases (HRPs). Owing to the abundance of biotinylated p8 proteins in M13 and the high molar ratio between HRP and streptavidin in streptavidin-polyHRP, the loading amount of HRP enzymes on the M13 bacteriophage were greatly boosted. Hence, the proposed method exhibited high sensitivity, with a limit of detection of 2.0 pg/mL for OTA detection, which was 250-fold lower than that of conventional ELISA. In addition, the proposed method showed a slight cross-reaction of 2.3% to OTB, a negligible cross-reaction for other common mycotoxins, and an acceptable accuracy for OTA quantitative detection in real corn samples. The practicability of the method was further confirmed with a traditional HRP-based ELISA method. In conclusion, the biotinylated bacteriophage and polyHRP structure showed potential as a cascade-amplifying enzyme loading system for ultra-trace OTA detemination, and its application can be extended to the detection of other analytes by altering specific mimic peptide sequences.

Download Full-text

Superior performance of human wastewater-associated viral markers compared to bacterial markers in tropical environments

10.1101/2020.10.26.355081 ◽

2020 ◽

Author(s):

Watsawan Sangkaew ◽

Akechai Kongprajug ◽

Natcha Chyerochana ◽

Warish Ahmed ◽

Skorn Mongkolsuk ◽

...

Keyword(s):

Water Quality ◽

Quality Management ◽

Water Quality Management ◽

High Sensitivity ◽

Superior Performance ◽

Source Tracking ◽

Marker Genes ◽

Aquatic Environments ◽

Detection Rates ◽

Central Thailand

AbstractIdentifying human sewage contamination via microbial source tracking (MST) marker genes has proven useful for effective water quality management worldwide; however, performance evaluations for these genes in tropical areas are limited. Therefore, this research assessed four human-associated MST marker genes in aquatic environments of Central Thailand: human polyomaviruses (JC and BK viruses [HPyVs]), bacteriophage crAssphage (CPQ_056), Lachnospiraceae Lachno3, and Bacteroides BacV6-21. HPyV and crAssphage assays were highly sensitive and specific to sewage (n = 19), with no cross-detection in 120 swine, cattle, chicken, duck, goat, sheep, and buffalo composite fecal samples. Lachno3 and BacV6-21 demonstrated high sensitivity but moderate specificity; however, using both markers could improve specificity to >0.80 (max value of 1.00). The most abundant markers in sewage were Lachno3 and BacV6-21 (5.42-8.02 and non-detected-8.05 log10 copies/100 mL), crAssphage (5.28-7.38 log10 copies/100 mL), and HPyVs (3.66-6.53 log10 copies/100 mL), respectively. HPyVs showed higher levels (up to 4.33 log10 copies/100 mL) and higher detection rates (92.7%) in two coastal beaches (n = 41) than crAssphage (up to 3.51 log10 copies/100 mL and 56.1%). HPyVs were also found at slightly lower levels (up to 5.10 log10 copies/100 mL), but at higher detection rates (92.6%), in a freshwater canal (n = 27) than crAssphage (up to 5.21 log10 copies/100 mL and 88.9%). Overall, both HPyVs and crAssphage are suggested as human sewage-associated MST markers in aquatic environments of Central Thailand. This study underlines the importance of characterizing and validating MST markers in host groups and environmental waters before including them in a water quality management toolbox.

Download Full-text

THE RELATIONSHIP BETWEEN TRANSFORMATIONAL LEADERSHIP AND SCHOOL EFFECTIVENESS IN TS25 SCHOOLS IN GUA MUSANG KELANTAN

International Journal of Education, Psychology and Counseling ◽

10.35631/ijepc.642016 ◽

2021 ◽

Vol 6 (42) ◽

pp. 204-214

Author(s):

Mohd Zainuddin Zakaria ◽

Siti Noor Ismail ◽

Yahya Don ◽

Wan Rosni Wan Yakob

Keyword(s):

Transformational Leadership ◽

School Effectiveness ◽

School Administrators ◽

Survey Method ◽

Ministry Of Education ◽

Cross Sectional Survey ◽

Cross Sectional ◽

High Performing ◽

High Level ◽

The Relationship

This study aims to identify the level of transformational leadership of principals and the level of school effectiveness in TS25 schools in Gua Musang District, Kelantan. In addition, this study also seeks to look at the relationship between the two variables involved, transformational leadership and school effectiveness. This quantitative study by cross-sectional survey method used two types of instruments, namely the Transformational leadership instrument by Leithwood and Jantzi (1999) and the school effectiveness instrument adapted from the study of Lazaridou and Iordanidis (2011. The sampling of the study involved four TS25 secondary schools with a total of 162 teachers. The findings of the study showed that the level of transformational leadership of principals and the level of school effectiveness was at a high level, with values (M = 4.17, SP = .604) and (M = 4.19, SP = .613) respectively. Further, correlation analysis showed that there was a very strong and significant relationship (r = .89, p <.01) between the two variables involved, namely transformational leadership and school effectiveness. It is hoped that the findings of this study can be used as a guide by the parties involved, especially the Ministry of Education Malaysia in strengthening the characteristics of high-performing leadership among school administrators towards improving school effectiveness through professionalism programs.

Download Full-text

Combating the COVID-19 Pandemic: Experiences of the First Wave From Nepal

Frontiers in Public Health ◽

10.3389/fpubh.2021.613402 ◽

2021 ◽

Vol 9 ◽

Author(s):

Buddha Bahadur Basnet ◽

Kiran Bishwakarma ◽

Ramesh Raj Pant ◽

Santosh Dhakal ◽

Nashib Pandey ◽

...

Keyword(s):

Economic Status ◽

Health Concern ◽

Vaccination Programs ◽

Significant Public Health Concern ◽

Hilly Region ◽

Travel Restrictions ◽

Significant Public Health ◽

The Government ◽

High Level ◽

Male To Female

Unprecedented and unforeseen highly infectious Coronavirus Disease 2019 (COVID-19) has become a significant public health concern for most of the countries worldwide, including Nepal, and it is spreading rapidly. Undoubtedly, every nation has taken maximum initiative measures to break the transmission chain of the virus. This review presents a retrospective analysis of the COVID-19 pandemic in Nepal, analyzing the actions taken by the Government of Nepal (GoN) to inform future decisions. Data used in this article were extracted from relevant reports and websites of the Ministry of Health and Population (MoHP) of Nepal and the WHO. As of January 22, 2021, the highest numbers of cases were reported in the megacity of the hilly region, Kathmandu district (population = 1,744,240), and Bagmati province. The cured and death rates of the disease among the tested population are ~98.00 and ~0.74%, respectively. Higher numbers of infected cases were observed in the age group 21–30, with an overall male to female death ratio of 2.33. With suggestions and recommendations from high-level coordination committees and experts, GoN has enacted several measures: promoting universal personal protection, physical distancing, localized lockdowns, travel restrictions, isolation, and selective quarantine. In addition, GoN formulated and distributed several guidelines/protocols for managing COVID-19 patients and vaccination programs. Despite robust preventive efforts by GoN, pandemic scenario in Nepal is, yet, to be controlled completely. This review could be helpful for the current and future effective outbreak preparedness, responses, and management of the pandemic situations and prepare necessary strategies, especially in countries with similar socio-cultural and economic status.

Download Full-text