ABSTRACT
Host genetic factors can confer resistance against malaria1, raising the question of whether this has led to evolutionary adaptation of parasite populations. Here we searched for association between candidate host and parasite genetic variants in 3,346 Gambian and Kenyan children with severe malaria caused by Plasmodium falciparum. We identified a strong association between sickle haemoglobin (HbS) in the host and three regions of the parasite genome, which is not explained by population structure or other covariates, and which is replicated in additional samples. The HbS-associated alleles include nonsynonymous variants in the gene for the acyl-CoA synthetase family member2-4 PfACS8 on chromosome 2, in a second region of chromosome 2, and in a region containing structural variation on chromosome 11. The alleles are in strong linkage disequilibrium and have frequencies that covary with the frequency of HbS across populations, in particular being much more common in Africa than other parts of the world. The estimated protective effect of HbS against severe malaria, as determined by comparison of cases with population controls, varies greatly according to the parasite genotype at these three loci. These findings open up a new avenue of enquiry into the biological and epidemiological significance of the HbS-associated polymorphisms in the parasite genome and the evolutionary forces that have led to their high frequency and strong linkage disequilibrium in African P. falciparum populations.
Subject(s)
Genotype , Hemoglobin, Sickle/genetics , Host Adaptation/genetics , Malaria, Falciparum/blood , Malaria, Falciparum/parasitology , Parasites/genetics , Plasmodium falciparum/genetics , Alleles , Animals , Child , Female , Gambia/epidemiology , Genes, Protozoan/genetics , Humans , Kenya/epidemiology , Linkage Disequilibrium , Malaria, Falciparum/epidemiology , Male , Polymorphism, GeneticABSTRACT
The evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus leads to new variants that warrant timely epidemiological characterization. Here we use the dense genomic surveillance data generated by the COVID-19 Genomics UK Consortium to reconstruct the dynamics of 71 different lineages in each of 315 English local authorities between September 2020 and June 2021. This analysis reveals a series of subepidemics that peaked in early autumn 2020, followed by a jump in transmissibility of the B.1.1.7/Alpha lineage. The Alpha variant grew when other lineages declined during the second national lockdown and regionally tiered restrictions between November and December 2020. A third more stringent national lockdown suppressed the Alpha variant and eliminated nearly all other lineages in early 2021. Yet a series of variants (most of which contained the spike E484K mutation) defied these trends and persisted at moderately increasing proportions. However, by accounting for sustained introductions, we found that the transmissibility of these variants is unlikely to have exceeded the transmissibility of the Alpha variant. Finally, B.1.617.2/Delta was repeatedly introduced in England and grew rapidly in early summer 2021, constituting approximately 98% of sampled SARS-CoV-2 genomes on 26 June 2021.
Subject(s)
COVID-19/epidemiology , COVID-19/virology , Genome, Viral/genetics , Genomics , SARS-CoV-2/genetics , Amino Acid Substitution , COVID-19/transmission , England/epidemiology , Epidemiological Monitoring , Humans , Molecular Epidemiology , Mutation , Quarantine/statistics & numerical data , SARS-CoV-2/classification , Spatio-Temporal Analysis , Spike Glycoprotein, Coronavirus/geneticsABSTRACT
The SARS-CoV-2 lineage B.1.1.7, designated variant of concern (VOC) 202012/01 by Public Health England1, was first identified in the UK in late summer to early autumn 20202. Whole-genome SARS-CoV-2 sequence data collected from community-based diagnostic testing for COVID-19 show an extremely rapid expansion of the B.1.1.7 lineage during autumn 2020, suggesting that it has a selective advantage. Here we show that changes in VOC frequency inferred from genetic data correspond closely to changes inferred by S gene target failures (SGTF) in community-based diagnostic PCR testing. Analysis of trends in SGTF and non-SGTF case numbers in local areas across England shows that B.1.1.7 has higher transmissibility than non-VOC lineages, even if it has a different latent period or generation time. The SGTF data indicate a transient shift in the age composition of reported cases, with cases of B.1.1.7 including a larger share of under 20-year-olds than non-VOC cases. We estimated time-varying reproduction numbers for B.1.1.7 and co-circulating lineages using SGTF and genomic data. The best-supported models did not indicate a substantial difference in VOC transmissibility among different age groups, but all analyses agreed that B.1.1.7 has a substantial transmission advantage over other lineages, with a 50% to 100% higher reproduction number.
Subject(s)
COVID-19/transmission , COVID-19/virology , Phylogeny , SARS-CoV-2/classification , SARS-CoV-2/pathogenicity , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Basic Reproduction Number , COVID-19/diagnosis , COVID-19/epidemiology , Child , Child, Preschool , England/epidemiology , Evolution, Molecular , Genome, Viral/genetics , Humans , Infant , Infant, Newborn , Middle Aged , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/analysis , Spike Glycoprotein, Coronavirus/genetics , Time Factors , Young AdultABSTRACT
The interaction between peptides and biological membranes is of fundamental importance in the mechanism of numerous membrane-mediated cellular processes, including antimicrobial peptide action, hormone-receptor interactions, drug bioavailability across the blood-brain barrier, and viral fusion processes [...].
Subject(s)
Lipid Bilayers , Peptides , Membranes , Cell MembraneABSTRACT
Resilience is of the upmost importance to deal with everyday problems faced by communities. The concept of community resilience is gaining prominence in disaster management policy and practice, and it has been shown to be an important factor during pandemic recovery such as during the SARS-CoV-2 outbreak. We present an instrument for community resilience assessment adapted for disasters like the pandemics. The instrument was based on the theory-based and evidence-informed Communities Advancing Resilience Toolkit (CART) Assessment Survey, adapted for the first time to Portuguese. Another strong feature of this study relates to the targeted participants, namely human service workers (598). They are key informants for their close involvement with communities. This version of the CART was reliable. A confirmatory factor analysis indicated a good relationship between the observed variables and their underlying latent constructs. Moreover, tests for measurement invariance across participants showed that differences in factor variances and covariances were not attributable to age-based differences in the properties of the scales themselves. Our findings support the fundamental idea that it is worthwhile to have an instrument to measure community resilience. Thus, our study adds to the evaluation of the CART, supporting its value as a robust instrument to measure resilience at the community level in different countries.
Subject(s)
COVID-19 , Disasters , Humans , SARS-CoV-2 , Ethnicity , Factor Analysis, StatisticalABSTRACT
PURPOSE: Enhanced cell proliferation in tumors can be associated with altered metabolic profiles and dramatic microenvironmental changes. Downfield magnetic resonance spectroscopy (MRS) has received increasing attention due to its ability to report on labile resonances of molecules not easily detected in upfield 1 H MRS. Image-selected-in-vivo-spectroscopy-relaxation enhanced MRS (iRE-MRS) was recently introduced for acquiring short echo-time (TE) spectra. Here, iRE-MRS was used to investigate in-vivo downfield spectra in glioma-bearing mice. METHODS: Experiments were performed in vivo in an immunocompetent glioma mouse model at 9.4 T using a cryogenic coil. iRE-MRS spectra were acquired in N = 6 glioma-bearing mice (voxel size = 2.23 mm3 ) and N = 6 control mice. Spectra were modeled by a sum of Lorentzian peaks simulating known downfield resonances, and differences between controls and tumors were quantified using relative peak areas. RESULTS: Short TE tumor spectra exhibited large qualitative differences compared to control spectra. Most peaks appeared modulated, with strong attenuation of NAA (â¼7.82, 7.86 ppm) and changes in relative peak areas between 6.75 and 8.49 ppm. Peak areas tended to be smaller for DF6.83 , DF7.60 , DF8.18 and NAA; and larger for DF7.95 and DF8.24 . Differences were also detected in signals resonating above 8.5 ppm, assumed to arise from NAD+. CONCLUSIONS: In-vivo downfield 1 H iRE-MRS of mouse glioma revealed differences between controls and tumor bearing mice, including in metabolites which are not easily detectable in the more commonly investigated upfield spectrum. These findings motivate future downfield MRS investigations exploring pH and exchange contributions to these differences.
Subject(s)
Brain Neoplasms , Glioma , Animals , Brain/metabolism , Brain Neoplasms/pathology , Disease Models, Animal , Glioma/pathology , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy/methods , MiceABSTRACT
The rapid and aggressive spread of artemisinin-resistant Plasmodium falciparum carrying the C580Y mutation in the kelch13 gene is a growing threat to malaria elimination in Southeast Asia, but there is no evidence of their spread to other regions. We conducted cross-sectional surveys in 2016 and 2017 at two clinics in Wewak, Papua New Guinea (PNG) where we identified three infections caused by C580Y mutants among 239 genotyped clinical samples. One of these mutants exhibited the highest survival rate (6.8%) among all parasites surveyed in ring-stage survival assays (RSA) for artemisinin. Analyses of kelch13 flanking regions, and comparisons of deep sequencing data from 389 clinical samples from PNG, Indonesian Papua and Western Cambodia, suggested an independent origin of the Wewak C580Y mutation, showing that the mutants possess several distinctive genetic features. Identity by descent (IBD) showed that multiple portions of the mutants' genomes share a common origin with parasites found in Indonesian Papua, comprising several mutations within genes previously associated with drug resistance, such as mdr1, ferredoxin, atg18 and pnp. These findings suggest that a P. falciparum lineage circulating on the island of New Guinea has gradually acquired a complex ensemble of variants, including kelch13 C580Y, which have affected the parasites' drug sensitivity. This worrying development reinforces the need for increased surveillance of the evolving parasite populations on the island, to contain the spread of resistance.
Subject(s)
Anti-Infective Agents , Artemisinins , Drug Resistance/genetics , Genes, Protozoan/genetics , Plasmodium falciparum/genetics , Anti-Infective Agents/therapeutic use , Artemisinins/therapeutic use , Cross-Sectional Studies , Humans , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology , Mutation , Papua New GuineaABSTRACT
Lantibiotics are a promising class of natural antimicrobial peptides. Lichenicidin is a two-peptide lantibiotic in which two mature peptides act synergistically to exhibit full bioactivity. Considering the two-peptide lantibiotics described so far, only cytolysin has been deeply characterized in terms of toxicity towards eukaryotic cells and it was found to be hemolytic and cytotoxic. This work aimed to improve the production of lichenicidin in vivo and characterize its antibacterial activity and toxicity against human cells. Peptides were purified and minimal inhibitory concentration (MIC) was determined against several strains; a time-kill assay was performed with Staphylococcus aureus. The hemolytic effect of lichenicidin was evaluated on blood samples from healthy donors and its toxicity towards human fibroblasts. The quantity of purified peptides was 1 mg/l Bliα and 0.4 mg/l Bliß. MIC for methicillin-sensitive and resistant S. aureus (MSSA and MRSA) strains were 16-32 µg/ml and 64-128 µg/ml, respectively. At the MIC, lichenicidin took less than 3 h to eliminate MSSA, indicating a strong bactericidal effect. It induces cell lysis at the highest concentration, an effect that might be potentiated by Bliß. Lichenicidin was not cytotoxic to human erythrocytes and fibroblasts. In this work, we evaluated the therapeutic potential of lichenicidin as a possible antimicrobial alternative.
Subject(s)
Anti-Infective Agents/pharmacology , Antimicrobial Peptides/pharmacology , Bacteria/drug effects , Bacterial Infections/drug therapy , Bacteriocins/pharmacology , Fibroblasts/drug effects , Peptides/pharmacology , Amino Acid Sequence , Anti-Infective Agents/chemistry , Anti-Infective Agents/isolation & purification , Antimicrobial Peptides/isolation & purification , Bacteriocins/chemistry , Bacteriocins/isolation & purification , Cell Line , Dose-Response Relationship, Drug , Drug Synergism , Hemolysis , Humans , Microbial Sensitivity TestsABSTRACT
PURPOSE: The construct of food addiction has been gaining increased attention as a research topic. Currently, the Yale Food Addiction Scale 2.0 is the only measure to operationalize the addictive-like eating behavior according to addiction criteria proposed by the Diagnostic and Statistical Manual of Mental Disorders. The present study aimed at examining the psychometric properties of the Portuguese version of the Yale Food Addiction Scale 2.0, as well as investigating the convergent and divergent validity between this scale and the following measures: Eating Disorders Examination Questionnaire, Body Investment Scale, and Difficulties in Emotion Regulation Scale. We also sought to explore the moderator role of difficulties in emotion regulation in the relationship between food addiction and binge eating METHODS: A sample of 302 female college students (Mage = 21.37, SD = 3.24) completed self-report measures. RESULTS: Sixteen (5.3%) participants were diagnosed as having food addiction. The confirmatory factor analysis suggested that the original one-dimensional structure is adequate to represent the Portuguese Yale Food Addiction Scale 2.0. The symptom count scores of the scale were correlated with body mass index, eating disordered behavior, body investment, and difficulties in emotion regulation. The severity level of the scale also discriminated the severity of eating disordered behaviors, body investment, and difficulties in emotion regulation. Finally, the relationship between food addiction and binge eating was moderated by difficulties engaging in goal-directed behavior when experiencing negative emotions. CONCLUSION: The Portuguese version of the Yale Food Addiction Questionnaire 2.0 may be a useful tool to investigate food addiction. LEVEL: IV descriptive studies.
Subject(s)
Behavior, Addictive , Food Addiction , Adult , Behavior, Addictive/diagnosis , Feeding Behavior/psychology , Female , Food Addiction/diagnosis , Food Addiction/psychology , Humans , Portugal , Psychiatric Status Rating Scales , Psychometrics/methods , Reproducibility of Results , Surveys and Questionnaires , Young AdultABSTRACT
PURPOSE: This study aimed to explore the early associations between the experienced psychosocial impact of the COVID-19 pandemic crisis during lockdown, depressive symptomatology, anxiety/stress levels, and disordered eating behaviors in adults during a first COVID-19 lockdown period. METHODS: This was a community-based cross-sectional study assessing 254 Portuguese adults (82.7% women; 35.82 ± 11.82 years) 1 week after the end of the first mandatory COVID-19 lockdown in Portugal. An online survey was conducted to evaluate psychological distress, disordered eating, and psychosocial impact of the COVID-19 pandemic. Pearson correlations and Structural Equation Modeling were performed. RESULTS: Participants reported the presence of meal skipping (52.8%), grazing eating behavior (80.9%), overeating (81.0%), loss of control over eating (47.2%), and binge eating episodes (39.2%) during lockdown. Structural equation modeling analyses, controlling for age and sex, indicated that there was a significant indirect effect of the experienced psychosocial impact of COVID-19 pandemic on disordered eating behaviors mediated through psychological distress. CONCLUSION: The psychosocial impact of the COVID-19 pandemic crisis may lead to disordered eating, and this relation may occur through the elevation of psychological distress. These findings can be used to inform interventions, to enhance mental health and manage disordered eating during similar future situations. Level of evidence V: cross-sectional descriptive study.
Subject(s)
COVID-19 , Feeding and Eating Disorders , Psychological Distress , Adult , Communicable Disease Control , Cross-Sectional Studies , Female , Humans , Male , Pandemics , SARS-CoV-2ABSTRACT
Background and Objectives: The COVID-19 pandemic impacted health systems worldwide, particularly cancer care. Because the actual implications of these changes on gynecological oncology healthcare are still unclear, we aim to evaluate the impact of this pandemic on the diagnosis and management of gynecological cancer. Materials and Methods: This is a single-center retrospective observational study, including patients diagnosed with gynecological malignancies between January 2019 and December 2021. Patients were included into three groups based on the timing of cancer diagnosis: pre-pandemic (2019), pandemic with high restrictions (2020) and pandemic recovery (2021). Results: Overall, 234 patients were diagnosed with gynecological cancer during the period of study. A decrease in the number of newly diagnosed cervical cancers and other rare tumors (leiomyosarcoma, invasive hydatidiform mole) was apparent in 2020. Some aggressive histological types of endometrial and ovarian cancer were more commonly diagnosed in the pandemic recovery group (p < 0.05), although no differences were demonstrated concerning tumor staging in all gynecological cancers. The median time between the first multidisciplinary team meeting and the treatment initiation was higher after the COVID-19 pandemic in endometrial cancer (23.0 vs. 34.0 vs. 36.0 days, p < 0.05). Patients with ovarian cancer were more frequently proposed for neoadjuvant therapy in 2020 compared to the other periods (33.3% vs. 55.0% vs. 10.0% p < 0.05). A significant reduction in the laparoscopic approach was observed during 2020 in endometrial cancer (32.1% vs. 14.3% vs. 36.4%, p < 0.05). No significant differences were registered regarding median hospitalization days or intra- and post-operative complications between these periods. Conclusions: The COVID-19 pandemic had a significant impact on the diagnosis and management of most gynecological malignancies, namely, on time to first treatment, chosen oncological therapies and surgical approaches. These results suggest important clinical and healthcare implications that should be addressed in future prospective studies.
Subject(s)
COVID-19 , Endometrial Neoplasms , Genital Neoplasms, Female , Ovarian Neoplasms , Female , Pregnancy , Humans , COVID-19/complications , Genital Neoplasms, Female/diagnosis , Genital Neoplasms, Female/epidemiology , Genital Neoplasms, Female/therapy , Pandemics , SARS-CoV-2 , Ovarian Neoplasms/pathology , Endometrial Neoplasms/pathologyABSTRACT
BACKGROUND: Artemisinin and partner-drug resistance in Plasmodium falciparum are major threats to malaria control and elimination. Triple artemisinin-based combination therapies (TACTs), which combine existing co-formulated ACTs with a second partner drug that is slowly eliminated, might provide effective treatment and delay emergence of antimalarial drug resistance. METHODS: In this multicentre, open-label, randomised trial, we recruited patients with uncomplicated P falciparum malaria at 18 hospitals and health clinics in eight countries. Eligible patients were aged 2-65 years, with acute, uncomplicated P falciparum malaria alone or mixed with non-falciparum species, and a temperature of 37·5°C or higher, or a history of fever in the past 24 h. Patients were randomly assigned (1:1) to one of two treatments using block randomisation, depending on their location: in Thailand, Cambodia, Vietnam, and Myanmar patients were assigned to either dihydroartemisinin-piperaquine or dihydroartemisinin-piperaquine plus mefloquine; at three sites in Cambodia they were assigned to either artesunate-mefloquine or dihydroartemisinin-piperaquine plus mefloquine; and in Laos, Myanmar, Bangladesh, India, and the Democratic Republic of the Congo they were assigned to either artemether-lumefantrine or artemether-lumefantrine plus amodiaquine. All drugs were administered orally and doses varied by drug combination and site. Patients were followed-up weekly for 42 days. The primary endpoint was efficacy, defined by 42-day PCR-corrected adequate clinical and parasitological response. Primary analysis was by intention to treat. A detailed assessment of safety and tolerability of the study drugs was done in all patients randomly assigned to treatment. This study is registered at ClinicalTrials.gov, NCT02453308, and is complete. FINDINGS: Between Aug 7, 2015, and Feb 8, 2018, 1100 patients were given either dihydroartemisinin-piperaquine (183 [17%]), dihydroartemisinin-piperaquine plus mefloquine (269 [24%]), artesunate-mefloquine (73 [7%]), artemether-lumefantrine (289 [26%]), or artemether-lumefantrine plus amodiaquine (286 [26%]). The median age was 23 years (IQR 13 to 34) and 854 (78%) of 1100 patients were male. In Cambodia, Thailand, and Vietnam the 42-day PCR-corrected efficacy after dihydroartemisinin-piperaquine plus mefloquine was 98% (149 of 152; 95% CI 94 to 100) and after dihydroartemisinin-piperaquine was 48% (67 of 141; 95% CI 39 to 56; risk difference 51%, 95% CI 42 to 59; p<0·0001). Efficacy of dihydroartemisinin-piperaquine plus mefloquine in the three sites in Myanmar was 91% (42 of 46; 95% CI 79 to 98) versus 100% (42 of 42; 95% CI 92 to 100) after dihydroartemisinin-piperaquine (risk difference 9%, 95% CI 1 to 17; p=0·12). The 42-day PCR corrected efficacy of dihydroartemisinin-piperaquine plus mefloquine (96% [68 of 71; 95% CI 88 to 99]) was non-inferior to that of artesunate-mefloquine (95% [69 of 73; 95% CI 87 to 99]) in three sites in Cambodia (risk difference 1%; 95% CI -6 to 8; p=1·00). The overall 42-day PCR-corrected efficacy of artemether-lumefantrine plus amodiaquine (98% [281 of 286; 95% CI 97 to 99]) was similar to that of artemether-lumefantrine (97% [279 of 289; 95% CI 94 to 98]; risk difference 2%, 95% CI -1 to 4; p=0·30). Both TACTs were well tolerated, although early vomiting (within 1 h) was more frequent after dihydroartemisinin-piperaquine plus mefloquine (30 [3·8%] of 794) than after dihydroartemisinin-piperaquine (eight [1·5%] of 543; p=0·012). Vomiting after artemether-lumefantrine plus amodiaquine (22 [1·3%] of 1703) and artemether-lumefantrine (11 [0·6%] of 1721) was infrequent. Adding amodiaquine to artemether-lumefantrine extended the electrocardiogram corrected QT interval (mean increase at 52 h compared with baseline of 8·8 ms [SD 18·6] vs 0·9 ms [16·1]; p<0·01) but adding mefloquine to dihydroartemisinin-piperaquine did not (mean increase of 22·1 ms [SD 19·2] for dihydroartemisinin-piperaquine vs 20·8 ms [SD 17·8] for dihydroartemisinin-piperaquine plus mefloquine; p=0·50). INTERPRETATION: Dihydroartemisinin-piperaquine plus mefloquine and artemether-lumefantrine plus amodiaquine TACTs are efficacious, well tolerated, and safe treatments of uncomplicated P falciparum malaria, including in areas with artemisinin and ACT partner-drug resistance. FUNDING: UK Department for International Development, Wellcome Trust, Bill & Melinda Gates Foundation, UK Medical Research Council, and US National Institutes of Health.
Subject(s)
Antimalarials/therapeutic use , Artemisinins/therapeutic use , Malaria, Falciparum/drug therapy , Adolescent , Adult , Amodiaquine/administration & dosage , Amodiaquine/therapeutic use , Anthraquinones/administration & dosage , Anthraquinones/therapeutic use , Antimalarials/administration & dosage , Artemether, Lumefantrine Drug Combination/administration & dosage , Artemether, Lumefantrine Drug Combination/therapeutic use , Artemisinins/administration & dosage , Drug Resistance , Drug Therapy, Combination , Female , Humans , Male , Mefloquine/administration & dosage , Mefloquine/therapeutic use , Plasmodium falciparum/drug effects , Polymerase Chain Reaction , Quinolines/administration & dosage , Quinolines/therapeutic use , Treatment Outcome , Young AdultABSTRACT
OBJECTIVES: The number of bacterial pathogens resistant to the currently available antibiotics has dramatically increased, with antimicrobial peptides (AMPs) being among the most promising potential new drugs. In this study, the applicability and mechanisms of action of Pa-MAP 2 and Pa-MAP 1.9, two AMPs synthetically designed based on a natural AMP template, were evaluated. METHODS: Pa-MAP 2 and Pa-MAP 1.9 were tested against a clinically isolated multidrug-resistant (MDR) Escherichia coli strain. Biophysical approaches were used to evaluate the preference of both peptides for specific lipid membranes, and bacterial surface changes imaged by atomic force microscopy (AFM). The efficacy of both peptides was assessed both in vitro and in vivo. RESULTS: Experimental results showed that both peptides have antimicrobial activity against the E. coli MDR strain. Zeta potential and surface plasmon resonance assays showed that they interact extensively with negatively charged membranes, changing from a random coil structure, when free in solution, to an α-helical structure after membrane interaction. The antibacterial efficacy was evaluated in vitro, by several techniques, and in vivo, using a wound infection model, showing a concentration-dependent antibacterial effect. Different membrane properties were evaluated to understand the mechanism underlying peptide action, showing that both promote destabilization of the bacterial surface, as imaged by AFM, and change properties such as membrane surface and dipole potential. CONCLUSIONS: Despite their similarity, data indicate that the mechanisms of action of the peptides are different, with Pa-MAP 1.9 being more effective than Pa-MAP 2. These results highlight their potential use as antimicrobial agents against MDR bacteria.
Subject(s)
Antimicrobial Cationic Peptides , Escherichia coli , Anti-Bacterial Agents/pharmacology , Antimicrobial Cationic Peptides/pharmacology , Drug Resistance, Multiple, Bacterial , Microbial Sensitivity Tests , PeptidesABSTRACT
BACKGROUND: Anti-malarial drug resistance remains a key concern for the global fight against malaria. In Ghana sulfadoxine-pyrimethamine (SP) is used for intermittent preventive treatment of malaria in pregnancy and combined with amodiaquine for Seasonal Malaria Chemoprevention (SMC) during the high malaria season. Thus, surveillance of molecular markers of SP resistance is important to guide decision-making for these interventions in Ghana. METHODS: A total of 4469 samples from uncomplicated malaria patients collected from 2009 to 2018 was submitted to the Wellcome Trust Sanger Institute, UK for DNA sequencing using MiSeq. Genotypes were successfully translated into haplotypes in 2694 and 846 mono infections respectively for pfdhfr and pfdhps genes and the combined pfhdfr/pfdhps genes across all years. RESULTS: At the pfdhfr locus, a consistently high (> 60%) prevalence of parasites carrying triple mutants (IRNI) were detected from 2009 to 2018. Two double mutant haplotypes (NRNI and ICNI) were found, with haplotype NRNI having a much higher prevalence (average 13.8%) than ICNI (average 3.2%) across all years. Six pfdhps haplotypes were detected. Of these, prevalence of five fluctuated in a downward trend over time from 2009 to 2018, except a pfdhps double mutant (AGKAA), which increased consistently from 2.5% in 2009 to 78.2% in 2018. Across both genes, pfdhfr/pfdhps combined triple (NRNI + AAKAA) mutants were only detected in 2009, 2014, 2015 and 2018, prevalence of which fluctuated between 3.5 and 5.5%. The combined quadruple (IRNI + AAKAA) genotype increased in prevalence from 19.3% in 2009 to 87.5% in 2011 before fluctuating downwards to 19.6% in 2018 with an average prevalence of 37.4% within the nine years. Prevalence of parasites carrying the quintuple (IRNI + AGKAA or SGEAA) mutant haplotypes, which are highly refractory to SP increased over time from 14.0% in 2009 to 89.0% in 2016 before decreasing to 78.9 and 76.6% in 2017 and 2018 respectively. Though quintuple mutants are rising in prevalence in both malaria seasons, together these combined genotypes vary significantly within season but not between seasons. CONCLUSIONS: Despite high prevalence of pfdhfr triple mutants and combined pfdhfr/pfdhps quadruple and quintuple mutants in this setting SP may still be efficacious. These findings are significant as they highlight the need to continuously monitor SP resistance, particularly using deep targeted sequencing to ascertain changing resistance patterns.
Subject(s)
Antimalarials/pharmacology , Drug Resistance/genetics , Genetic Variation , Genotype , Malaria, Falciparum/prevention & control , Plasmodium falciparum/genetics , Pyrimethamine/pharmacology , Sulfadoxine/pharmacology , Adolescent , Child , Child, Preschool , Drug Combinations , Female , Genetic Variation/drug effects , Ghana , Humans , Male , Plasmodium falciparum/drug effects , Seasons , Young AdultABSTRACT
OBJECTIVES: Among outpatients with eating disorders (ED), we compared participants without nonsuicidal self-injury (non-NSSI group), with NSSI over a year ago (past NSSI group) and with NSSI in the previous year (current NSSI group) regarding different variables, and examined whether difficulties in emotion regulation and negative urgency moderated the relationship between maternal/paternal invalidation and NSSI. METHOD: The sample included 171 outpatients (94.2% female; Mage = 28.78, SDage = 11.19). RESULTS: Fifty-four participants (31.6%) had NSSI in the previous year. This group showed higher eating pathology, difficulties in emotion regulation, negative urgency, and maternal/paternal invalidation than the non-NSSI group. Analyses revealed an adequate fit to the data for the model that included moderating effects of emotional awareness and negative urgency in the relationship between maternal/paternal invalidation and increased likelihood of NSSI in the previous year. CONCLUSIONS: Interventions for NSSI and ED should include emotion regulation, impulse control, and validation strategies.
Subject(s)
Emotional Regulation , Feeding and Eating Disorders/psychology , Outpatients/psychology , Self-Injurious Behavior/psychology , Adolescent , Adult , Female , Humans , Male , Middle Aged , Young AdultABSTRACT
PURPOSE: Athletes who perform combat sports tend to engage in weight-management strategies to fit in a specific weight class that are characterized by disordered eating behaviours. This study aimed to (1) characterize eating behaviours and adaptation to stress regarding an unwanted weight change before a competition; (2) evaluate the differences between athletes who consider unwanted weight changes as a challenge or as a threat in regard to emotions, coping strategies and eating behaviours; and (3) evaluate whether some of these variables related to the unwanted weight change (e.g., emotions, cognitive appraisal of the situation) are predictors of disordered eating behaviours in combat sports. METHODS: A total of 166 combat sports athletes (75.3% male), aged between 14 and 56 years (M = 22.73; SD = 8.03), filled out a set of questionnaires that evaluated personal variables, cognitive appraisal (threat/challenge), coping, emotions, and eating behaviours related to an unwanted weight change before a competition. RESULTS: Most of the athletes (57.3%) reported high levels of stress related to the experience of an unwanted weight change before a competition. Athletes who perceived this experience as more of a threat had significantly more eating concerns, anxiety, dejection, anger, active confrontation and emotional support. Athletes who perceived it as more of a challenge experienced more excitement and happiness. Athletes who perceived a high threat and low challenge experienced significantly increased anxiety levels and athletes who perceived this experience as a low threat and the low challenge had decreased anxiety. The desire to weigh less, the perception of a threat regarding weight changes, the ability to cope with denial, and anxiety emerged as predictors of disordered eating behaviours. CONCLUSION: To prevent or reduce disordered eating behaviours, it is important to promote adequate strategies to deal with weight changes before a competition and, consequently, positive emotions among sports combat athletes. LEVEL OF EVIDENCE: Level III, case-control analytic study.
Subject(s)
Feeding and Eating Disorders , Sports , Adolescent , Adult , Athletes , Emotions , Feeding Behavior , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , Young AdultABSTRACT
PURPOSE: Grazing is a problematic eating behavior linked with poor weight loss outcomes, disordered eating psychopathology, and psychological distress in the adult population. However, no study assessed this behavior in children. Childhood is an important time frame for the development and maintenance of healthy eating habits, which can be influenced by children's psychological state, eating habits, and parental practices. This study investigates the associations between grazing behavior in children and children's psychological variables (anxiety, depression and withdrawn symptoms, body image dissatisfaction), children eating habits, and parental feeding practices. METHODS: In this cross-sectional study, 330 primary school students (6-10 years old) and their parents completed measures assessing children's grazing, anxiety/depression and withdrawn symptoms, body image dissatisfaction, children eating habits and style, and parental feeding practices. RESULTS: The path analysis tested showed that more restrictive parental feeding practices, inappropriate children eating habits, children's anxiety/depression symptoms, and body image dissatisfaction were associated with increased grazing scores (CMIN = 12.679; DF = 11; p = 0.315; RMSEA = 0.025; CFI = 0.990; NFI = 0.935; TLI = 0.982; IFI = 0.991; SRMR = 0.045). CONCLUSION: Grazing tends to occur in a context of children's psychological distress, inappropriate children eating habits, and restrictive parental feeding practices. These variables should be addressed for the improvement of healthy eating habits and in weight-loss interventions for children. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.
Subject(s)
Feeding Behavior , Parents , Adult , Child , Child Behavior , Cross-Sectional Studies , Humans , Parent-Child Relations , Parenting , Surveys and QuestionnairesABSTRACT
Huntington's disease (HD) is a neurodegenerative disorder causing cognitive and motor impairments, evolving to death within 15-20 years after symptom onset. We previously established a mouse model with the entire human HD gene containing 128 CAG repeats (YAC128) which accurately recapitulates the natural history of the human disease. Defined time points in this natural history enable the understanding of longitudinal trajectories from the neurochemical and structural points of view using non-invasive high-resolution multi-modal imaging. Accordingly, we designed a longitudinal structural imaging (MRI and DTI) and spectroscopy (1H-MRS) study in YAC128, at 3, 6, 9 and 12 months of age, at 9.4 T. Structural analysis (MRI/DTI), confirmed that the striatum is the earliest affected brain region, but other regions were also identified through connectivity analysis (pre-frontal cortex, hippocampus, globus pallidus and thalamus), suggesting a striking homology with the human disease. Importantly, we found for the first time, a negative correlation between striatal and hippocampal changes only in YAC128. In fact, the striatum showed accelerated volumetric decay in HD, as opposed to the hippocampus. Neurochemical analysis of the HD striatum suggested early neurometabolic alterations in neurotransmission and metabolism, with a significant increase in striatal GABA levels, and specifically anticorrelated levels of N-acetyl aspartate and taurine, suggesting that the later is homeostatically adjusted for neuroprotection, as neural loss, indicated by the former, is progressing. These results provide novel insights into the natural history of HD and prove a valuable role for longitudinal multi-modal panels of structural and metabolite/neurotransmission in the YAC128 model.
Subject(s)
Brain/metabolism , Corpus Striatum/metabolism , Huntingtin Protein/genetics , Huntington Disease/genetics , Animals , Brain/diagnostic imaging , Brain/pathology , Corpus Striatum/diagnostic imaging , Corpus Striatum/pathology , Disease Models, Animal , Gene Expression Regulation/genetics , Humans , Huntington Disease/diagnostic imaging , Huntington Disease/pathology , Longitudinal Studies , Mice , Mice, Transgenic , Neostriatum/diagnostic imaging , Neostriatum/metabolism , Neostriatum/pathology , Neurons/metabolism , Neurons/pathology , Thalamus/diagnostic imaging , Thalamus/metabolism , Thalamus/pathology , Trinucleotide Repeats/genetics , gamma-Aminobutyric Acid/genetics , gamma-Aminobutyric Acid/metabolismABSTRACT
Ctn[15-34], the C-terminal fragment of crotalicidin, an antimicrobial peptide from the South American rattlesnake Crotalus durissus terrificus venom, displays remarkable anti-infective and anti-proliferative activities. Herein, its activity on Candida albicans biofilms and its interaction with the cytoplasmic membrane of the fungal cell and with a biomembrane model in vitro was investigated. A standard C. albicans strain and a fluconazole-resistant clinical isolate were exposed to the peptide at its minimum inhibitory concentration (MIC) (10 µM) and up to 100 × MIC to inhibit biofilm formation and its eradication. A viability test using XTT and fluorescent dyes, confocal laser scanning microscopy, and atomic force microscopy (AFM) were used to observe the antibiofilm effect. To evaluate the importance of membrane composition on Ctn[15-34] activity, C. albicans protoplasts were also tested. Fluorescence assays using di-8-ANEPPS, dynamic light scattering, and zeta potential measurements using liposomes, protoplasts, and C. albicans cells indicated a direct mechanism of action that was dependent on membrane interaction and disruption. Overall, Ctn[15-34] showed to be an effective antifungal peptide, displaying antibiofilm activity and, importantly, interacting with and disrupting fungal plasma membrane.