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1.
Mol Ecol ; 33(13): e17425, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38847383

RESUMO

Annual rhythms are observed in living organisms with numerous ecological implications. In the zooplanktonic copepod Calanus finmarchicus, such rhythms are crucial regarding its phenology, body lipid accumulation, and global carbon storage. Climate change drives annual biological rhythms out of phase with the prevailing environmental conditions with yet unknown but potentially catastrophic consequences. However, the molecular dynamics underlying phenology are still poorly described. In a rhythmic analysis of C. finmarchicus annual gene expression, results reveal that more than 90% of the transcriptome shows significant annual rhythms, with abrupt and dramatic upheaval between the active and diapause life cycle states. This work explores the implication of the circadian clock in the annual timing, which may control epigenetic mechanisms to profoundly modulate gene expression in response to calendar time. Results also suggest an increased light sensitivity during diapause that would ensure the photoperiodic entrainment of the endogenous annual clock.


Assuntos
Relógios Circadianos , Copépodes , Diapausa , Transcriptoma , Animais , Copépodes/genética , Copépodes/fisiologia , Diapausa/genética , Relógios Circadianos/genética , Fotoperíodo , Estações do Ano , Mudança Climática , Zooplâncton/genética , Ritmo Circadiano/genética
2.
Head Neck ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850089

RESUMO

BACKGROUND: Head and neck cancer (HNC) incidence is on the rise, often diagnosed at late stage and associated with poor prognoses. Risk prediction tools have a potential role in prevention and early detection. METHODS: The IARC-ARCAGE European case-control study was used as the model development dataset. A clinical HNC risk prediction model using behavioral and demographic predictors was developed via multivariable logistic regression analyses. The model was then externally validated in the UK Biobank cohort. Model performance was tested using discrimination and calibration metrics. RESULTS: 1926 HNC cases and 2043 controls were used for the development of the model. The development dataset model including sociodemographic, smoking, and alcohol variables had moderate discrimination, with an area under curve (AUC) value of 0.75 (95% CI, 0.74-0.77); the calibration slope (0.75) and tests were suggestive of good calibration. 384 616 UK Biobank participants (with 1177 HNC cases) were available for external validation of the model. Upon external validation, the model had an AUC of 0.62 (95% CI, 0.61-0.64). CONCLUSION: We developed and externally validated a HNC risk prediction model using the ARCAGE and UK Biobank studies, respectively. This model had moderate performance in the development population and acceptable performance in the validation dataset. Demographics and risk behaviors are strong predictors of HNC, and this model may be a helpful tool in primary dental care settings to promote prevention and determine recall intervals for dental examination. Future addition of HPV serology or genetic factors could further enhance individual risk prediction.

3.
Arch Dis Child ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38724064

RESUMO

OBJECTIVES: To quantify levels of coexisting obesity and caries experience in children in Scotland, and any associated socioeconomic inequalities over the years 2011/2012-2017/2018. DESIGN: A multicohort population-wide data linkage study. SETTING: Local authority primary schools in Scotland. PATIENTS: 335 361 primary 1 (approximately 5 years old) schoolchildren in Scotland between 2011/2012 and 2017/2018. MAIN OUTCOME MEASURES: Prevalence and inequalities in coexisting caries and obesity. RESULTS: The prevalence of coexisting obesity and caries experience was 3.4% (n=11 494 of 335 361) and did not change over the 7 years. Children living in the 20% most deprived areas had more than sixfold greater odds of coexisting obesity and caries experience than children from the 20% least deprived areas (adjusted OR=6.63 (95% CI=6.16 to 7.14; p<0.001)). There was a large persistent socioeconomic gradient across the Scottish Index of Multiple Deprivation groups, with the Slope and Relative Indices of Inequality remaining unchanged over the 7 cohort years. CONCLUSIONS: Despite improvements in oral health in children in Scotland, the prevalence of coexisting obesity and caries experience has remained static, with large persistent inequalities. These conditions are likely to signal increased risk of chronic conditions including multimorbidity in adulthood and therefore early identification of children most at risk and timely intervention tackling common risk factors should be developed and evaluated.

4.
JCO Glob Oncol ; 10: e2300343, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38603656

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is well known as a serious health problem worldwide, especially in low-income countries or those with limited resources, such as most countries in Latin America. International guidelines cannot always be applied to a population from a large region with specific conditions. This study established a Latin American guideline for care of patients with head and neck cancer and presented evidence of HNSCC management considering availability and oncologic benefit. A panel composed of 41 head and neck cancer experts systematically worked according to a modified Delphi process on (1) document compilation of evidence-based answers to different questions contextualized by resource availability and oncologic benefit regarding Latin America (region of limited resources and/or without access to all necessary health care system infrastructure), (2) revision of the answers and the classification of levels of evidence and degrees of recommendations of all recommendations, (3) validation of the consensus through two rounds of online surveys, and (4) manuscript composition. The consensus consists of 12 sections: Head and neck cancer staging, Histopathologic evaluation of head and neck cancer, Head and neck surgery-oral cavity, Clinical oncology-oral cavity, Head and neck surgery-oropharynx, Clinical oncology-oropharynx, Head and neck surgery-larynx, Head and neck surgery-larynx/hypopharynx, Clinical oncology-larynx/hypopharynx, Clinical oncology-recurrent and metastatic head and neck cancer, Head and neck surgery-reconstruction and rehabilitation, and Radiation therapy. The present consensus established 48 recommendations on HNSCC patient care considering the availability of resources and focusing on oncologic benefit. These recommendations could also be used to formulate strategies in other regions like Latin America countries.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , América Latina/epidemiologia , Consenso , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/terapia
5.
Clin Otolaryngol ; 49(4): 363-375, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38514776

RESUMO

OBJECTIVES: This rapid review aims to evaluate the impact of the COVID-19 pandemic on incidence of head and neck cancer (HNC) and stage distribution at diagnosis. DESIGN: Rapid review and meta-analysis. PARTICIPANTS: Comparative data for new HNC patients between a pre-pandemic cohort (before March 2020) and a pandemic cohort (after March 2020 during the lockdown period). MAIN OUTCOMES MEASURED: Data on tumour stage, incidence, referral pathway (number of new patient referrals), or workload levels (number of HNC treatments). Data on stage were summarised as odds ratios (OR) with 95% confidence intervals (CI), and data related to changes in numbers of diagnoses, referrals, and workload levels were summarised as a narrative synthesis. RESULTS: A total of 31 reports were included in this review. Individually 16 out of 23 studies did not show a significant impact on stage relative to the pre-pandemic period. However, the meta-analysis revealed that patients diagnosed with HNC during the pandemic were 16% more likely to have nodal involvement (OR = 1.16; 95% CI 1.00-1.35), 17% more likely to have a late overall stage (OR = 1.17; 95% CI 1.01-1.36), and 32% more likely to present with advanced tumour extent (T3 and T4 stage) (OR = 1.32; 95% CI 1.08-1.62). Data on incidence was extremely limited and not currently sufficient to assess trends in burden of disease. CONCLUSIONS: This review indicates that during the COVID-19 pandemic, there was upstaging of HNC at diagnosis, suggesting the provision of care to HNC patients was significantly affected.


Assuntos
COVID-19 , Neoplasias de Cabeça e Pescoço , Estadiamento de Neoplasias , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Neoplasias de Cabeça e Pescoço/epidemiologia , Incidência , Pandemias
6.
mBio ; 15(5): e0314023, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38530030

RESUMO

The Plasmodium falciparum merozoite surface protein MSPDBL2 is a polymorphic antigen targeted by acquired immune responses, and normally expressed in only a minority of mature schizonts. The potential relationship of MSPDBL2 to sexual commitment is examined, as variable mspdbl2 transcript levels and proportions of MSPDBL2-positive mature schizonts in clinical isolates have previously correlated with levels of many sexual stage parasite gene transcripts, although not with the master regulator ap2-g. It is demonstrated that conditional overexpression of the gametocyte development protein GDV1, which promotes sexual commitment, also substantially increases the proportion of MSPDBL2-positive schizonts in culture. Conversely, truncation of the gdv1 gene is shown to prevent any expression of MSPDBL2. However, across diverse P. falciparum cultured lines, the variable proportions of MSPDBL2 positivity in schizonts do not correlate significantly with variable gametocyte conversion rates, indicating it is not involved in sexual commitment. Confirming this, examining a line with endogenous hemagglutinin-tagged AP2-G showed that the individual schizonts expressing MSPDBL2 are mostly different from those expressing AP2-G. Using a selection-linked integration system, modified P. falciparum lines were engineered to express an intact or disrupted version of MSPDBL2, showing the protein is not required for sexual commitment or early gametocyte development. Asexual parasite multiplication rates were also not affected by expression of either intact or disrupted MSPDBL2 in a majority of schizonts. Occurring alongside sexual commitment, the role of the discrete MSPDBL2-positive schizont subpopulation requires further investigation in natural infections where it is under immune selection. IMPORTANCE: Malaria parasites in the blood are remarkably variable, able to switch antigenic targets so they may survive within humans who have already developed specific immune responses. This is one of the challenges in developing vaccines against malaria. MSPDBL2 is a target of naturally acquired immunity expressed in minority proportions of schizonts, the end stages of each 2-day replication cycle in red blood cells which contain merozoites prepared to invade new red blood cells. Results show that the proportion of schizonts expressing MSPDBL2 is positively controlled by the expression of the regulatory gametocyte development protein GDV1. It was previously known that expression of GDV1 leads to increased expression of AP2-G which causes parasites to switch to sexual development, so a surprising finding here is that MSPDBL2-positive parasites are mostly distinct from those that express AP2-G. This discrete antigenic subpopulation of mostly asexual parasites is regulated alongside sexually committed parasites, potentially enabling survival under stress conditions.


Assuntos
Antígenos de Protozoários , Plasmodium falciparum , Proteínas de Protozoários , Esquizontes , Plasmodium falciparum/genética , Plasmodium falciparum/imunologia , Plasmodium falciparum/crescimento & desenvolvimento , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/imunologia , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Antígenos de Protozoários/metabolismo , Esquizontes/metabolismo , Esquizontes/imunologia , Esquizontes/genética , Humanos , Malária Falciparum/parasitologia , Malária Falciparum/imunologia , Regulação da Expressão Gênica , Eritrócitos/parasitologia
8.
Malar J ; 23(1): 22, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38229097

RESUMO

BACKGROUND: Chronic carriage of asymptomatic low-density Plasmodium falciparum parasitaemia in the dry season may support maintenance of acquired immunity that protects against clinical malaria. However, the relationship between chronic low-density infections and subsequent risk of clinical malaria episodes remains unclear. METHODS: In a 2-years study (December 2014 to December 2016) in eastern Gambia, nine cross-sectional surveys using molecular parasite detection were performed in the dry and wet season. During the 2016 malaria transmission season, passive case detection identified episodes of clinical malaria. RESULTS: Among the 5256 samples collected, 444 (8.4%) were positive for P. falciparum. A multivariate model identified village of residence, male sex, age ≥ 5 years old, anaemia, and fever as independent factors associated with P. falciparum parasite carriage. Infections did not cluster over time within the same households or recurred among neighbouring households. Asymptomatic parasite carriage at the end of dry season was associated with a higher risk of infection (Hazard Ratio, HR = 3.0, p < 0.0001) and clinical malaria (HR = 1.561, p = 0.057) during the following transmission season. Age and village of residence were additional predictors of infection and clinical malaria during the transmission season. CONCLUSION: Chronic parasite carriage during the dry season is associated with an increased risk of malaria infection and clinical malaria. It is unclear whether this is due to environmental exposure or to other factors.


Assuntos
Malária Falciparum , Malária , Masculino , Humanos , Pré-Escolar , Plasmodium falciparum , Estações do Ano , Gâmbia/epidemiologia , Estudos Transversais , Malária Falciparum/diagnóstico , Prevalência
9.
Evid Based Dent ; 25(1): 25-26, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38182661

RESUMO

DATA SOURCES: Four electronic databases: MEDLINE (via Ovid), Embase (via Ovid), Web of Science, and American Psychology Association PsycINFO. STUDY SELECTION: Quantitative observational or interventional studies, published until the end of February 2022 with no restrictions to date, language, or region of publication. DATA EXTRACTION AND SYNTHESIS: Screening performed by one author and a second author independently reviewed a random sample of 10% of the articles. Disagreements were resolved in consultation with a third author. RESULTS: The results were presented as a narrative review due to large heterogeneity of data. Nine studies met the eligibility criteria and most of them were rated as fair quality. The main factors influencing refugees access to dental care services were demographic and socioeconomic characteristics and English language proficiency. CONCLUSIONS: The review suggests that individual-level factors may have a predisposing effect on refugees' access, but had limited evidence on other enabling and contextual factors.


Assuntos
Refugiados , Humanos , Fatores Socioeconômicos , Assistência Odontológica
10.
Int J Cancer ; 154(2): 389-402, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37694289

RESUMO

A growing proportion of head and neck cancer (HNC), especially oropharyngeal cancer (OPC), is caused by human papillomavirus (HPV). There are several markers for HPV-driven HNC, one being HPV early antigen serology. We aimed to investigate the diagnostic accuracy of HPV serology and its performance across patient characteristics. Data from the VOYAGER consortium was used, which comprises five studies on HNC from North America and Europe. Diagnostic accuracy, that is, sensitivity, specificity, Cohen's kappa and correctly classified proportions of HPV16 E6 serology, was assessed for OPC and other HNC using p16INK4a immunohistochemistry (p16), HPV in situ hybridization (ISH) and HPV PCR as reference methods. Stratified analyses were performed for variables including age, sex, smoking and alcohol use, to test the robustness of diagnostic accuracy. A risk-factor analysis based on serology was conducted, comparing HPV-driven to non-HPV-driven OPC. Overall, HPV serology had a sensitivity of 86.8% (95% CI 85.1-88.3) and specificity of 91.2% (95% CI 88.6-93.4) for HPV-driven OPC using p16 as a reference method. In stratified analyses, diagnostic accuracy remained consistent across sex and different age groups. Sensitivity was lower for heavy smokers (77.7%), OPC without lymph node involvement (74.4%) and the ARCAGE study (66.7%), while specificity decreased for cases with <10 pack-years (72.1%). The risk-factor model included study, year of diagnosis, age, sex, BMI, alcohol use, pack-years, TNM-T and TNM-N stage. HPV serology is a robust biomarker for HPV-driven OPC, and its diagnostic accuracy is independent of age and sex. Future research is suggested on the influence of smoking on HPV antibody levels.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Humanos , Papillomavirus Humano 16 , Papillomavirus Humano , Neoplasias de Cabeça e Pescoço/diagnóstico
13.
Cancers (Basel) ; 15(17)2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37686681

RESUMO

Head and neck cancer (HNC) treatments have been based on single or multimodal therapies with surgery, radiotherapy (RT), chemotherapy, and immunotherapy. However, treatment recommendations among countries may differ due to technological/human resources and usual local practices. This scoping review aims to identify, compare, and map the clinical practice guidelines (CPGs) for treating squamous cell carcinoma (SCC) of the oral cavity, oropharynx, and larynx worldwide. A search strategy on global CPGs for HNC was performed by using five electronic databases and grey literature. CPGs were selected for inclusion using EndNote-20 and Rayyan online software. No language or publication date restrictions were applied. The results were analyzed descriptively considering the most updated CPG version. In total, 25 CPGs covering the head and neck region (10), the larynx (7), the oral cavity (5), and the oropharynx (3), were found in 13 geographical regions, and 19 were developed by medical societies from 1996 to 2023. Surgery and RT remain the main modalities for early-stage HNC, with surgery preferred in low-resource countries, and RT in selected cases, especially in the larynx/oropharynx aiming to achieve a cure with organ preservation. Human papillomavirus infection for oropharyngeal SCC is not tested in some Asian countries and there is still no consensus to treat p16-positive cases differently from p16-negative. Recommendations for larynx preservation vary according to facilities in each country, however, individualized choice is emphasized. Inequality across countries/continents is evident, with a similar pattern of recommendations among developed as well as developing ones. No CPGs were found in Latin America as well as Oceania countries, where the incidence of HNC is high and limitations of access to treatment may be encountered.

14.
Cochrane Database Syst Rev ; 8: CD006205, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37650478

RESUMO

BACKGROUND: Surgery is a common treatment option in oral cavity cancer (and less frequently in oropharyngeal cancer) to remove the primary tumour and sometimes neck lymph nodes. People with early-stage disease may undergo surgery alone or surgery plus radiotherapy, chemotherapy, immunotherapy/biotherapy, or a combination of these. Timing and extent of surgery varies. This is the third update of a review originally published in 2007. OBJECTIVES: To evaluate the relative benefits and harms of different surgical treatment modalities for oral cavity and oropharyngeal cancers. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was 9 February 2022. SELECTION CRITERIA: Randomised controlled trials (RCTs) that compared two or more surgical treatment modalities, or surgery versus other treatment modalities, for primary tumours of the oral cavity or oropharynx. DATA COLLECTION AND ANALYSIS: Our primary outcomes were overall survival, disease-free survival, locoregional recurrence, and recurrence; and our secondary outcomes were adverse effects of treatment, quality of life, direct and indirect costs to patients and health services, and participant satisfaction. We used standard Cochrane methods. We reported survival data as hazard ratios (HRs). For overall survival, we reported the HR of mortality, and for disease-free survival, we reported the combined HR of new disease, progression, and mortality; therefore, HRs below 1 indicated improvement in these outcomes. We used GRADE to assess certainty of evidence for each outcome. MAIN RESULTS: We identified four new trials, bringing the total number of included trials to 15 (2820 participants randomised, 2583 participants analysed). For objective outcomes, we assessed four trials at high risk of bias, three at low risk, and eight at unclear risk. The trials evaluated nine comparisons; none compared different surgical approaches for excision of the primary tumour. Five trials evaluated elective neck dissection (ND) versus therapeutic (delayed) ND in people with oral cavity cancer and clinically negative neck nodes. Elective ND compared with therapeutic ND probably improves overall survival (HR 0.64, 95% confidence interval (CI) 0.50 to 0.83; I2 = 0%; 4 trials, 883 participants; moderate certainty) and disease-free survival (HR 0.56, 95% CI 0.45 to 0.70; I2 = 12%; 5 trials, 954 participants; moderate certainty), and probably reduces locoregional recurrence (HR 0.58, 95% CI 0.43 to 0.78; I2 = 0%; 4 trials, 458 participants; moderate certainty) and recurrence (RR 0.58, 95% CI 0.48 to 0.70; I2 = 0%; 3 trials, 633 participants; moderate certainty). Elective ND is probably associated with more adverse events (risk ratio (RR) 1.31, 95% CI 1.11 to 1.54; I2 = 0%; 2 trials, 746 participants; moderate certainty). Two trials evaluated elective radical ND versus elective selective ND in people with oral cavity cancer, but we were unable to pool the data as the trials used different surgical procedures. Neither study found evidence of a difference in overall survival (pooled measure not estimable; very low certainty). We are unsure if there is a difference in effect on disease-free survival (HR 0.57, 95% CI 0.29 to 1.11; 1 trial, 104 participants; very low certainty) or recurrence (RR 1.21, 95% CI 0.63 to 2.33; 1 trial, 143 participants; very low certainty). There may be no difference between the interventions in terms of adverse events (1 trial, 148 participants; low certainty). Two trials evaluated superselective ND versus selective ND, but we were unable to use the data. One trial evaluated supraomohyoid ND versus modified radical ND in 332 participants. We were unable to use any of the primary outcome data. The evidence on adverse events was very uncertain, with more complications, pain, and poorer shoulder function in the modified radical ND group. One trial evaluated sentinel node biopsy versus elective ND in 279 participants. There may be little or no difference between the interventions in overall survival (HR 1.00, 95% CI 0.90 to 1.11; low certainty), disease-free survival (HR 0.98, 95% CI 0.90 to 1.07; low certainty), or locoregional recurrence (HR 1.04, 95% CI 0.91 to 1.19; low certainty). The trial provided no usable data for recurrence, and reported no adverse events (very low certainty). One trial evaluated positron emission tomography-computed tomography (PET-CT) following chemoradiotherapy (with ND only if no or incomplete response) versus planned ND (before or after chemoradiotherapy) in 564 participants. There is probably no difference between the interventions in overall survival (HR 0.92, 95% CI 0.65 to 1.31; moderate certainty) or locoregional recurrence (HR 1.00, 95% CI 0.94 to 1.06; moderate certainty). One trial evaluated surgery plus radiotherapy versus radiotherapy alone and provided very low-certainty evidence of better overall survival in the surgery plus radiotherapy group (HR 0.24, 95% CI 0.10 to 0.59; 35 participants). The data were unreliable because the trial stopped early and had multiple protocol violations. In terms of adverse events, subcutaneous fibrosis was more frequent in the surgery plus radiotherapy group, but there were no differences in other adverse events (very low certainty). One trial evaluated surgery versus radiotherapy alone for oropharyngeal cancer in 68 participants. There may be little or no difference between the interventions for overall survival (HR 0.83, 95% CI 0.09 to 7.46; low certainty) or disease-free survival (HR 1.07, 95% CI 0.27 to 4.22; low certainty). For adverse events, there were too many outcomes to draw reliable conclusions. One trial evaluated surgery plus adjuvant radiotherapy versus chemotherapy. We were unable to use the data for any of the outcomes reported (very low certainty). AUTHORS' CONCLUSIONS: We found moderate-certainty evidence based on five trials that elective neck dissection of clinically negative neck nodes at the time of removal of the primary oral cavity tumour is superior to therapeutic neck dissection, with increased survival and disease-free survival, and reduced locoregional recurrence. There was moderate-certainty evidence from one trial of no difference between positron emission tomography (PET-CT) following chemoradiotherapy versus planned neck dissection in terms of overall survival or locoregional recurrence. The evidence for each of the other seven comparisons came from only one or two studies and was assessed as low or very low-certainty.


Assuntos
Recidiva Local de Neoplasia , Neoplasias Orofaríngeas , Humanos , Imunoterapia , Boca , Pescoço , Neoplasias Orofaríngeas/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Br Dent J ; 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225842

RESUMO

Introduction This study aimed to quantify the impact of the COVID-19 pandemic on access and inequalities in primary care dental services among children and adults in Scotland.Methods Access was measured as any NHS Scotland primary care dental contacts derived from administrative data from January 2019 to May 2022, linked to the area-based Scottish Index of Multiple Deprivation for children and adults, and related to population denominator estimates from National Record Scotland. Inequalities for pre-pandemic (January 2019-January 2020) and recent (December 2021-February 2022, and March 2022-May 2022) periods for both children and adults were calculated and compared using the slope index of inequality and relative index of inequality.Results Following the first lockdown (March 2020) there was a dramatic fall to near zero dental contacts, followed by a slow recovery to 64.8% of pre-pandemic levels by May 2022. There was initial widening of relative inequalities in dental contacts in early 2022, which, more recently, had begun to return to pre-pandemic levels.Conclusion COVID-19 had a major impact on access to NHS primary dental care, and while inequalities in access are apparent as services recover from lockdown, these inequalities are not a new phenomenon.

16.
Microb Genom ; 9(5)2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37204422

RESUMO

Experimental studies on the biology of malaria parasites have mostly been based on laboratory-adapted lines, but there is limited understanding of how these may differ from parasites in natural infections. Loss-of-function mutants have previously been shown to emerge during culture of some Plasmodium falciparum clinical isolates in analyses focusing on single-genotype infections. The present study included a broader array of isolates, mostly representing multiple-genotype infections, which are more typical in areas where malaria is highly endemic. Genome sequence data from multiple time points over several months of culture adaptation of 28 West African isolates were analysed, including previously available sequences along with new genome sequences from additional isolates and time points. Some genetically complex isolates eventually became fixed over time to single surviving genotypes in culture, whereas others retained diversity, although proportions of genotypes varied over time. Drug resistance allele frequencies did not show overall directional changes, suggesting that resistance-associated costs are not the main causes of fitness differences among parasites in culture. Loss-of-function mutants emerged during culture in several of the multiple-genotype isolates, affecting genes (including AP2-HS, EPAC and SRPK1) for which loss-of-function mutants were previously seen to emerge in single-genotype isolates. Parasite clones were derived by limiting dilution from six of the isolates, and sequencing identified de novo variants not detected in the bulk isolate sequences. Interestingly, several of these were nonsense mutants and frameshifts disrupting the coding sequence of EPAC, the gene with the largest number of independent nonsense mutants previously identified in laboratory-adapted lines. Analysis of genomic identity by descent to explore relatedness among clones revealed co-occurring non-identical sibling parasites, illustrative of the natural genetic structure within endemic populations.


Assuntos
Malária , Plasmodium falciparum , Humanos , Plasmodium falciparum/genética , Genótipo , Genômica , Fatores de Troca do Nucleotídeo Guanina/genética , Proteínas Serina-Treonina Quinases/genética
17.
Nat Microbiol ; 8(7): 1213-1226, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37169919

RESUMO

Malaria parasites break down host haemoglobin into peptides and amino acids in the digestive vacuole for export to the parasite cytoplasm for growth: interrupting this process is central to the mode of action of several antimalarial drugs. Mutations in the chloroquine (CQ) resistance transporter, pfcrt, located in the digestive vacuole membrane, confer CQ resistance in Plasmodium falciparum, and typically also affect parasite fitness. However, the role of other parasite loci in the evolution of CQ resistance is unclear. Here we use a combination of population genomics, genetic crosses and gene editing to demonstrate that a second vacuolar transporter plays a key role in both resistance and compensatory evolution. Longitudinal genomic analyses of the Gambian parasites revealed temporal signatures of selection on a putative amino acid transporter (pfaat1) variant S258L, which increased from 0% to 97% in frequency between 1984 and 2014 in parallel with the pfcrt1 K76T variant. Parasite genetic crosses then identified a chromosome 6 quantitative trait locus containing pfaat1 that is selected by CQ treatment. Gene editing demonstrated that pfaat1 S258L potentiates CQ resistance but at a cost of reduced fitness, while pfaat1 F313S, a common southeast Asian polymorphism, reduces CQ resistance while restoring fitness. Our analyses reveal hidden complexity in CQ resistance evolution, suggesting that pfaat1 may underlie regional differences in the dynamics of resistance evolution, and modulate parasite resistance or fitness by manipulating the balance between both amino acid and drug transport.


Assuntos
Cloroquina , Malária Falciparum , Humanos , Sistemas de Transporte de Aminoácidos/metabolismo , Cloroquina/metabolismo , Cloroquina/farmacologia , Resistência a Medicamentos/genética , Malária Falciparum/parasitologia , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo
18.
Wellcome Open Res ; 8: 22, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36864926

RESUMO

We describe the MalariaGEN Pf7 data resource, the seventh release of Plasmodium falciparum genome variation data from the MalariaGEN network.  It comprises over 20,000 samples from 82 partner studies in 33 countries, including several malaria endemic regions that were previously underrepresented.  For the first time we include dried blood spot samples that were sequenced after selective whole genome amplification, necessitating new methods to genotype copy number variations.  We identify a large number of newly emerging crt mutations in parts of Southeast Asia, and show examples of heterogeneities in patterns of drug resistance within Africa and within the Indian subcontinent.  We describe the profile of variations in the C-terminal of the csp gene and relate this to the sequence used in the RTS,S and R21 malaria vaccines.  Pf7 provides high-quality data on genotype calls for 6 million SNPs and short indels, analysis of large deletions that cause failure of rapid diagnostic tests, and systematic characterisation of six major drug resistance loci, all of which can be freely downloaded from the MalariaGEN website.

19.
Clin Otolaryngol ; 48(4): 587-594, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36929626

RESUMO

OBJECTIVES: To evaluate the impact of the COVID-19 lockdown measures on HNC, by comparing the stage at presentation and treatment of HNC before and after the most severe COVID-19 restrictions. DESIGN: A retrospective cohort study. SETTING: A regional cancer network serving a patient population of 2.4 million. PARTICIPANTS: Newly diagnosed patients with HNC between June and October 2019 (pre-pandemic) and June and October 2021 (post-pandemic). MAIN OUTCOME MEASURES: Symptom duration before diagnosis, stage at diagnosis, patient performance status (PS) and intent of treatment delivered (palliative vs. curative). RESULTS: Five hundred forty-five patients were evaluated-250 in the 2019 and 295 in the 2021 cohort. There were no significant differences in symptom duration between the cohorts (p = .359) or patient PS (p = .821). There were no increased odds of presenting with a late (Stage III or IV) AJCC cancer stage in 2021 compared with 2019 (odds ratio [OR] = 0.90; 95% confidence interval [CI]: 0.76-1.08); nor increased odds of receiving palliative rather than curative treatment in 2021 compared with 2019 (OR = 0.68; 95% CI: 0.45-1.03). CONCLUSION: The predicted stage shift to more advanced disease at the time of diagnosis of HNC due to the COVID-19 pandemic has not been realised in the longer term. In keeping with this, there was no difference in symptom duration, patient PS, or treatment patterns between the 2019 and 2021 cohorts.


Assuntos
COVID-19 , Neoplasias de Cabeça e Pescoço , Humanos , Pandemias , Estudos Retrospectivos , Controle de Doenças Transmissíveis
20.
Community Dent Oral Epidemiol ; 51(1): 133-138, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36753390

RESUMO

In the early 2000s, a Scottish Government Oral Health Action Plan identified the need for a national programme to improve child oral health and reduce inequalities. 'Childsmile' aimed to improve child oral health in Scotland, reduce inequalities in outcomes and access to dental services, and to shift the balance of care from treatment to prevention through targeted and universal components in dental practice, community and educational settings. This paper describes how an embedded, theory-based research and evaluation arm with multi-disciplinary input helps determine priorities and provides important strategic direction. Programme theory is articulated in dedicated, dynamic logic models, and evaluation themes are as follows: population-level data linkage; trials and economic evaluations; investigations drawing from behavioural and implementation science; evidence reviews and updates; and applications of systems science. There is also a growing knowledge sharing network internationally. Collaborative working from all stakeholders is necessary to maintain gains and to address areas that may not be working as well, and never more so with the major disruptions to the programme from the COVID-19 pandemic and response. Conclusions are that evaluation and research are synergistic with a complex, dynamic programme like Childsmile. The evidence obtained allows for appraisal of the relative strengths of component interventions and the reach and impact of Childsmile to feed into national policy.


Assuntos
COVID-19 , Assistência Odontológica para Crianças , Criança , Humanos , Saúde Bucal , Pandemias , Escócia/epidemiologia
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