scholarly journals Shifts in P. falciparum genetic structure and gametocyte markers in the transition to elimination

2020 ◽  
Author(s):  
Himanshu Gupta ◽  
Beatriz Galatas ◽  
Arlindo Chidimatembue ◽  
Wilson Simone ◽  
Gloria Matambisso ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Plasmodium Falciparum ◽  
Genetic Structure ◽  
Large Scale ◽  
Reverse Transcription Pcr ◽  
Mature Gametocyte ◽  
Before And After ◽  
Sexual Stages ◽  
The Impact ◽  
Pcr Targeting

Abstract Large-scale programs targeting Plasmodium falciparum (Pf) elimination can exert strong selection pressures on the parasite population. To better understand the impact that elimination initiatives can have on Pf genetic structure and gametocyte carriage, we applied amplicon-based sequencing of two polymorphic Pf genes and quantitative reverse-transcription PCR targeting gametocyte-specific genes to Pf isolates collected in Magude District (Southern Mozambique) before and after an elimination initiative. The 71% reduction of Pf prevalence achieved in 2 years was followed by reductions in Pf genetic diversity and increases in between-infection similarity. These genetic shifts were accompanied by increases in the relative transcript number of the female mature gametocyte marker pfs25, the pfap2g transcription factor that drives gametocytogenesis and the sexual ring marker pfgexp02, suggesting the parasite ability of adapting its sexual investment during elimination initiatives. Reactive interventions that target Pf sexual stages may be required to achieve complete interruption of transmission.

scholarly journals Genetic diversity of Plasmodium falciparum populations in three malaria transmission settings in Madagascar

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Fanomezantsoa Ralinoro ◽  
Tovonahary Angelo Rakotomanga ◽  
Rianasoambolanoro Rakotosaona ◽  
Danielle A. Doll Rakoto ◽  
Didier Menard ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Plasmodium Falciparum ◽  
Malaria Transmission ◽  
Nested Pcr ◽  
Drug Efficacy ◽  
Control Measures ◽  
Epidemiological Strata ◽  
Allele Specific ◽  
The Impact ◽  
Pcr Targeting

Abstract Background Assessment of the genetic diversity of Plasmodium falciparum parasites from various malaria transmission settings could help to define tailored local strategies for malaria control and elimination. Such assessments are currently scarce in Madagascar. The study presented here aimed to bridge this gap by investigating the genetic diversity of P. falciparum populations in three epidemiological strata (Equatorial, Tropical and Fringes) in Madagascar. Methods Two-hundred and sixty-six P. falciparum isolates were obtained from patients with uncomplicated malaria enrolled in clinical drug efficacy studies conducted at health centres in Tsaratanana (Equatorial stratum), Antanimbary (Tropical stratum) and Anjoma Ramartina (Fringes) in 2013 and 2016. Parasite DNA was extracted from blood samples collected before anti-malarial treatment. Plasmodium species were identified by nested PCR targeting the 18 S rRNA gene. The genetic profiles of P. falciparum parasites were defined by allele-specific nested PCR on the polymorphic regions of the msp-1 and msp-2 genes. Results Fifty-eight alleles were detected in the P. falciparum samples tested: 18 alleles for msp-1 and 40 for msp-2. K1 (62.9%, 139/221) and FC27 (69.5%, 114/164) were the principal msp-1 and msp-2 allele families detected, although the proportions of the msp-1 and msp-2 alleles varied significantly between sites. Polyclonal infections were more frequent at sites in the Equatorial stratum (69.8%) than at sites in the Tropical stratum (60.5%) or Fringes (58.1%). Population genetics analyses showed that genetic diversity was similar between sites and that parasite flow within sites was limited. Conclusions This study provides recent information about the genetic diversity of P. falciparum populations in three transmission strata in Madagascar, and valuable baseline data for further evaluation of the impact of the control measures implemented in Madagascar.

scholarly journals Genetic Diversity of Plasmodium Falciparum Populations in three Malaria Transmission Settings in Madagascar

2021 ◽  
Author(s):  
Fanomezantsoa Ralinoro ◽  
Tovonahary Angelo Rakotomanga ◽  
Riana Rakotosaona ◽  
Danielle A. Doll Rakoto ◽  
Didier Menard ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Plasmodium Falciparum ◽  
Malaria Transmission ◽  
Drug Efficacy ◽  
Control Measures ◽  
Health Centers ◽  
Allele Specific ◽  
Genetic Profiles ◽  
The Impact ◽  
Pcr Targeting

Abstract BackgroundThe assessment of the genetic diversity of Plasmodium falciparum parasites from various malaria transmission settings could help to define tailored and dedicated local strategies for malaria control and elimination. To date, this information is scarce in Madagascar. To fill this gap, a study aiming at investigating the genetic diversity of P. falciparum populations in three epidemiological facies (Equatorial, Tropical and Fringes) in Madagascar was conducted.MethodsTwo hundred sixty-six P. falciparum isolates were obtained from patients with uncomplicated malaria enrolled in clinical drug efficacy studies conducted in health centers at Tsaratanana (Equatorial facies), Antanimbary (Tropical facies) and Anjoma Ramartina (Fringes) in 2013 and 2016. Parasite DNA was extracted from blood samples collected prior antimalarial treatment. Plasmodium species were identified by nested-PCR targeting 18S rRNA gene. The genetic profiles of P. falciparum parasites were defined by assessing the polymorphic regions of the msp-1 and msp-2 genes using allele-specific nested-PCR.ResultsA total of 58 alleles were detected for msp-1 (18 alleles) and msp-2 (40 alleles) among P. falciparum samples tested. K1 (62.9%, 139/221) and FC27 (69.5%, 114/164) were the most predominant msp-1 and msp-2 allelic families, although the proportions of the msp-1 and msp-2 alleles varied significantly between sites. Polyclonal infections were more frequent in site located in the Equatorial facies (69.8%) compared to sites in the Tropical facies (60.5%) and Fringes (58.1%). Population genetic measures showed that the genetic diversity was similar between sites and the parasite flow within sites was limited.ConclusionThis study provides recent information on the genetic diversity of P. falciparum populations in three transmission facies in Madagascar and valuable baseline data to further evaluate the impact of the control measures implemented in Madagascar.

scholarly journals Impact of cyclones on hard coral and metapopulation structure, connectivity and genetic diversity of coral reef fish

Coral Reefs ◽  
2021 ◽  
Author(s):  
Gabriele Gerlach ◽  
Philipp Kraemer ◽  
Peggy Weist ◽  
Laura Eickelmann ◽  
Michael J. Kingsford
Keyword(s):  
Genetic Diversity ◽  
Coral Reef ◽  
Genetic Structure ◽  
Reef Fish ◽  
Coral Reef Fish ◽  
Population Genetic Study ◽  
Hard Coral ◽  
Great Loss ◽  
Metapopulation Structure ◽  
The Impact

AbstractCyclones have one of the greatest effects on the biodiversity of coral reefs and the associated species. But it is unknown how stochastic alterations in habitat structure influence metapopulation structure, connectivity and genetic diversity. From 1993 to 2018, the reefs of the Capricorn Bunker Reef group in the southern part of the Great Barrier Reef were impacted by three tropical cyclones including cyclone Hamish (2009, category 5). This resulted in substantial loss of live habitat-forming coral and coral reef fish communities. Within 6–8 years after cyclones had devastated, live hard corals recovered by 50–60%. We show the relationship between hard coral cover and the abundance of the neon damselfish (Pomacentrus coelestis), the first fish colonizing destroyed reefs. We present the first long-term (2008–2015 years corresponding to 16–24 generations of P. coelestis) population genetic study to understand the impact of cyclones on the meta-population structure, connectivity and genetic diversity of the neon damselfish. After the cyclone, we observed the largest change in the genetic structure at reef populations compared to other years. Simultaneously, allelic richness of genetic microsatellite markers dropped indicating a great loss of genetic diversity, which increased again in subsequent years. Over years, metapopulation dynamics were characterized by high connectivity among fish populations associated with the Capricorn Bunker reefs (2200 km2); however, despite high exchange, genetic patchiness was observed with annual strong genetic divergence between populations among reefs. Some broad similarities in the genetic structure in 2015 could be explained by dispersal from a source reef and the related expansion of local populations. This study has shown that alternating cyclone-driven changes and subsequent recovery phases of coral habitat can greatly influence patterns of reef fish connectivity. The frequency of disturbances determines abundance of fish and genetic diversity within species.

The Importance of Similarity: How Gender Congruence Matters for the Impact of Leadership Training

2021 ◽  
pp. 009539972110642
Author(s):  
Trine H. Fjendbo ◽  
Christian B. Jacobsen ◽  
Seung-Ho An
Keyword(s):  
Leadership Training ◽  
Large Scale ◽  
Leadership Behaviors ◽  
Leadership Behavior ◽  
Female Gender ◽  
Perceived Leadership ◽  
Scale Field ◽  
Before And After ◽  
Large Scale Field ◽  
The Impact

Leadership training is key to promoting more active leadership, but the effects of leadership training can depend on the gender context. Gender congruence between manager and employee can affect how the manager employs leadership behaviors adapted from training and how employees perceive leadership behavior. Quantitative data on 474 managers’ 4,833 employees before and after a large-scale field experiment with leadership training enable us to examine changes in employee-perceived leadership following training. The results show that gender congruence between manager and employee is associated with stronger leadership training effects on employee-perceived leadership behaviors. Female gender congruence shows the most pronounced effects.

scholarly journals Impact of the first COVID-19 shelter-in-place order in the United States on emergency department utilization, Marin County, California

2020 ◽  
Author(s):  
Brett R. Bayles ◽  
Michaela F George ◽  
Haylea Hannah ◽  
Patti Culross ◽  
Rochelle R. Ereman ◽  
...  
Keyword(s):  
United States ◽  
San Francisco ◽  
Large Scale ◽  
Temporal Dynamics ◽  
The United States ◽  
Emergency Department Utilization ◽  
Marin County ◽  
Before And After ◽  
Ed Visits ◽  
The Impact

Background: The first shelter-in-place (SIP) order in the United States was issued across six counties in the San Francisco Bay Area to reduce the impact of COVID-19 on critical care resources. We sought to assess the impact of this large-scale intervention on emergency departments (ED) in Marin County, California. Methods: We conducted a retrospective descriptive and trend analysis of all ED visits in Marin County, California from January 1, 2018 to May 4, 2020 to quantify the temporal dynamics of ED utilization before and after the March 17, 2020 SIP order. Results: The average number of ED visits per day decreased by 52.3% following the SIP order compared to corresponding time periods in 2018 and 2019. Both respiratory and non-respiratory visits declined, but this negative trend was most pronounced for non-respiratory admissions. Conclusions: The first SIP order to be issued in the United States in response to COVID-19 was associated with a significant reduction in ED utilization in Marin County.

scholarly journals Intraspecific divergences and phylogeography of Panzerina lanata (Lamiaceae) in Northwest China

2018 ◽  
Author(s):  
Yanfen Zhao ◽  
Hongxiang Zhang ◽  
Borong Pan ◽  
Mingli Zhang
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Population Genetic ◽  
Divergence Time ◽  
Northwest China ◽  
Northwestern China ◽  
Intraspecific Diversity ◽  
Early Pleistocene ◽  
Helan Mountains ◽  
The Impact

Climactic fluctuations during the Quaternary played a crucial role in genetic diversity and population genetic structure of many plant species in northwestern China. In order to understand the impact of climate change on herbaceous plants, we studied Panzerina lanata (Lamiaceae), a widely distributed species. Two chloroplast DNA intergenic spacers (trnH-psbA and rpoB-trnC) were used to sequence 269 individuals from 27 populations and seven haplotypes were identified. Genetic structure and demographic characteristics were estimated using AMOVA, neutrality tests, and mismatch distribution analyses. The divergence times between the seven haplotypes were estimated using Beast. Our results revealed high levels of total genetic diversity (HT = 0.673±0.0869) and low levels of average within-population genetic diversity (HS = 0.033±0.0214). The analysis of molecular variance indicated major genetic differentiation among the three groups: northern, central, and eastern group. The species distribution modeling and demographic analysis indicated that P. lanata has not experience a recent range expansion. The divergence time within P. lanata occurred between the early Pleistocene and the late Pleistocene, which coincides with aridification and the expansion of the deserts in northwestern China that resulted in species diversification and habitat fragmentation. In addition, we speculate that the deserts and the Helan Mountains acted as effective geographic barriers that led to intraspecific diversity.

scholarly journals Energy conservation by retrofitting of dwellings

2019 ◽  
Vol 111 ◽  
pp. 03010
Author(s):  
Imrich Sánka ◽  
Dušan Petráš
Keyword(s):  
Large Scale ◽  
Thermal Environment ◽  
Winter Season ◽  
Residential Building ◽  
Indoor Environmental Quality ◽  
Air Exchange Rate ◽  
Energy Auditing ◽  
Before And After ◽  
The Impact

This article investigates the impact of energy renovation on the indoor environmental quality of apartment building during heating season. The study was performed in one residential building before and after its renovation. Energy auditing and classification of the selected building into energy classes were carried out. Additionally, evaluation of indoor air quality was performed using objective measurements and subjective survey. Thermal environment and concentration of CO2 was measured in bedrooms. Higher concentrations of CO2 was observed in the residential building after its renovation. The concentrations of CO2, in some cases exceeded the recommended maximum limits, especially after implementing of energy saving measures on the building. The average air exchange rate was visible higher before renovation of the building. The current study indicates that large-scale of renovations may reduce the quality of the indoor environment in many apartments, especially in the winter season.

Cigarette and cigar sales in Hawaii before and after implementation of a Tobacco 21 Law

2020 ◽  
Vol 30 (1) ◽  
pp. 98-102 ◽  
Author(s):  
Rebecca Glover-Kudon ◽  
Doris G Gammon ◽  
Todd Rogers ◽  
Ellen M Coats ◽  
Brett Loomis ◽  
...  
Keyword(s):  
Large Scale ◽  
Geographical Area ◽  
Upward Trend ◽  
Food Stores ◽  
The Us ◽  
Before And After ◽  
Youth And Young Adults ◽  
The Usa ◽  
Product Sales ◽  
The Impact

IntroductionOn 1 January 2016, Hawaii raised the minimum legal age for tobacco access from 18 to 21 years (‘Tobacco 21 (T21)’) statewide, with no special population exemptions. We assessed the impact of Hawaii’s T21 policy on sales of cigarettes and large cigars/cigarillos in civilian food stores, including menthol/flavoured product sales share.MethodsCigarette and large cigar/cigarillo sales and menthol/flavoured sales share were assessed in Hawaii, California (implemented T21 in June 2016 with a military exemption), and the US mainland using the only Nielsen data consistently available for each geographical area. Approximate monthly sales data from large-scale food stores with sales greater than US$2 million/year covered June 2012 to February 2017. Segmented regression analyses estimated changes in sales from prepolicy to postpolicy implementation periods.ResultsFollowing T21 in Hawaii, average monthly cigarette unit sales dropped significantly (−4.4%, p<0.01) coupled with a significant decrease in menthol market share (−0.8, p<0.01). This combination of effects was not observed in comparison areas. Unit sales of large cigars/cigarillos decreased significantly in each region following T21 implementation. T21 policies in Hawaii and California showed no association with flavoured/menthol cigar sales share, but there was a significant increase in flavoured/menthol cigar sales share in the USA (7.1%, p<0.01) relative to Hawaii’s implementation date, suggesting T21 may have attenuated an otherwise upward trend.ConclusionsAs part of a comprehensive approach to prevent or delay tobacco use initiation, T21 laws may help to reduce sales of cigarette and large cigar products most preferred by US youth and young adults.

scholarly journals DNA recovery from archived RDTs for genetic characterization of Plasmodium falciparum in a routine setting in Lambaréné, Gabon

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
The Trong Nguyen ◽  
Brice Nzigou Mombo ◽  
Albert Lalremruata ◽  
Erik Koehne ◽  
Rella Zoleko Manego ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Real Time ◽  
Real Time Pcr ◽  
Rural Areas ◽  
Large Scale ◽  
Genetic Material ◽  
Chloroquine Resistance ◽  
Dna Recovery ◽  
Parasite Populations ◽  
Pcr Targeting

Abstract Background Rapid diagnostic tests (RDTs) have been described as a source of genetic material to analyse malaria parasites in proof-of-concept studies. The increasing use of RDTs (e.g., in focal or mass screening and treatment campaigns) makes this approach particularly attractive for large-scale investigations of parasite populations. In this study, the complexity of Plasmodium falciparum infections, parasite load and chloroquine resistance transporter gene mutations were investigated in DNA samples extracted from positive RDTs, obtained in a routine setting and archived at ambient temperature. Methods A total of 669 archived RDTs collected from malaria cases in urban, semi-urban and rural areas of central Gabon were used for P. falciparum DNA extraction. Performance of RDTs as a source of DNA for PCR was determined using: (i) amplification of a single copy merozoite surface protein 1 (msp1) gene followed by highly sensitive and automated capillary electrophoresis; (ii) genotyping of the pfcrt gene locus 72–76 using haplotype-specific-probe-based real-time PCR to characterize chloroquine resistance; and, (iii) real-time PCR targeting 18S genes to detect and quantify Plasmodium parasites. Results Out of the 669 archived RDTs, amplification of P. falciparum nucleic materials had a success rate of 97% for 18S real-time PCR, and 88% for the msp1 gene. The multiplicity of infections (MOI) of the whole population was 2.6 (95% CI 2.5–2.8). The highest number of alleles detected in one infection was 11. The MOI decreased with increasing age (β = − 0.0046, p = 0.02) and residence in Lambaréné was associated with smaller MOIs (p < 0.001). The overall prevalence of mutations associated with chloroquine resistance was 78.5% and was not associated with age. In Lambaréné, prevalence of chloroquine resistance was lower compared to rural Moyen-Ogooué (β = − 0.809, p-value = 0.011). Conclusion RDT is a reliable source of DNA for P. falciparum detection and genotyping assays. Furthermore, the increasing use of RDTs allows them to be an alternative source of DNA for large-scale genetic epidemiological studies. Parasite populations in the study area are highly diverse and prevalence of chloroquine-resistant P. falciparum remains high, especially in rural areas.

Impact of a Large-Scale Coach Education Program from a Lifelong-Learning Perspective

2013 ◽  
Vol 6 (1) ◽  
pp. 23-42 ◽  
Author(s):  
Diana Deek ◽  
Penny Werthner ◽  
Kyle J. Paquette ◽  
Diane Culver
Keyword(s):  
Lifelong Learning ◽  
Education Program ◽  
Large Scale ◽  
Learning Experience ◽  
Coach Education ◽  
Coach Learning ◽  
Before And After ◽  
Coaching Certification ◽  
The Impact ◽  
Depth Interviews

This study examines the impact of a coach education program on coach learning and perceived changes to coaching practices, while situating this episodic learning experience within a lifelong-learning perspective. Three sets of in-depth interviews were conducted with 10 coaches taking part in one of three competition-development modules within Canada’s National Coaching Certification Program (Coaching and Leading Effectively, Managing Conflict, and Psychology of Performance). It was found that (a) the coaches’ biographies varied widely, (b) all of the coaches reported learning from the modules, (c) eight of ten coaches reported a change in their coaching practices as a result of participation in one of the modules, and (d) the coaches credited a combination of mediated, unmediated, and internal learning situations for their learning before and after the modules. These findings suggest that a large-scale coach education program can have an impact on coaches when the program takes a lifelong-learning perspective and integrates constructivist principles into its design and delivery.

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