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1.
Intensive Crit Care Nurs ; : 103694, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38653631

RESUMO

INTRODUCTION: Early recognition and prompt, appropriate management may reduce mortality in patients with sepsis. The Surviving Sepsis Campaign's guidelines suggest the use of dynamic measurements to guide fluid resuscitation in sepsis; although these methods are rarely employed to monitor cardiac output in response to fluid administration outside intensive care units. This service evaluation investigated the introduction of a nurse led protocolised goal-directed fluid management using a non-invasive cardiac output monitor to the standard assessment of hypotensive ward patients. METHODS: We introduced the use of a goal-directed fluid management protocol into our critical care outreach teams' standard clinical assessment. Forty-nine sequential patients before and thirty-nine after its introduction were included in the assessment. RESULTS: Patients in the post-intervention cohort received less fluid in the 6 h following outreach assessment (750mls vs 1200mls). There were no differences in clinical background or rates of renal replacement therapy, but rates of invasive and non-invasive ventilation were reduced (0% vs 31%). Although the groups were similar, the post-intervention patients had lower recorded blood pressures. CONCLUSION: IV fluid therapy in the patient with hypotension complicating sepsis can be challenging. Excessive IV fluid administration is commonplace and associated with harm, and the use of advanced non-invasive haemodynamic monitoring by trained nurses can provide objective evaluation of individualised response to treatment. Avoiding excessive IV fluid and earlier institution of appropriate vasopressor therapy may improve patient outcomes. IMPLICATIONS FOR CLINICAL PRACTICE: Adoption of dynamic measures of cardiac output outside of critical care by trained critical care nurses is feasible and may translate into improved patient outcomes. In hospitals with a nurse-led critical care outreach service, consideration should be given to such an approach.

2.
Insect Sci ; 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38556782

RESUMO

The vast majority of all global species have circadian rhythm cycles that allow them to adapt to natural environments. These regular rhythms are regulated by core clock genes and recent studies have also implicated roles for microRNAs in this regulation. Oviposition is an important circadian behavior in the reproductive cycle of insect vectors of diseases, and little is known about the rhythm or its regulation in mosquitoes. Aedes albopictus is a diurnal mosquito that transmits arboviruses and is the major cause of outbreaks of dengue fever in China. We analyzed the oviposition rhythm patterns of A. albopictus under different light/dark conditions and show that the mosquitoes have an oviposition peak between zeitgeber time 9 (ZT 9) and ZT 12. Furthermore, the antagomir-mediated knockdown of expression of the microRNA miR-2940-1 affected the oviposition rhythm of A. albopictus. These data support the conclusion that miR-2940-1 is involved in the regulation of oviposition rhythm in A. albopictus and provide a foundation for using oviposition rhythms as a new target for vector mosquito control.

3.
BMJ Ment Health ; 27(1)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38670574

RESUMO

BACKGROUND: There are significant clinical, policy and societal concerns about the impact on young people (YP), from admission to psychiatric wards far from home. However, research evidence is scarce. AIMS: To investigate the impact of at-distance admissions to general adolescent units, from the perspectives of YP, parents/carers and healthcare professionals (HCPs) including service commissioners, to inform clinical practice, service development and policy. METHOD: Semistructured interviews with purposive samples of YP aged 13-17 years (n=28) and parents/carers (n=19) across five large regions in England, and a national sample of HCPs (n=51), were analysed using a framework approach. RESULTS: There was considerable agreement between YP, parents/carers and HCPs on the challenges of at-distance admissions. YP and parents/carers had limited or no involvement in decision-making processes around admission and highlighted a lack of available information about individual units. Being far from home posed challenges with maintaining home contact and practical/financial challenges for families visiting. HCPs struggled with ensuring continuity of care, particularly around maintaining access to local clinical teams and educational support. However, some YP perceived separation from their local environment as beneficial because it removed them from unhelpful environments. At-distance admissions provided respite for some families struggling to support their child. CONCLUSIONS: At-distance admissions lead to additional distress, uncertainty, compromised continuity of care and educational, financial and other practical difficulties, some of which could be better mitigated. For a minority, there are some benefits from such admissions. CLINICAL IMPLICATIONS: Standardised online information, accessible prior to admission, is needed for all Child and Adolescent Mental Health Services units. Additional practical and financial burden placed on families needs greater recognition and consideration of potential sources of support. Policy changes should incorporate findings that at-distance or adult ward admissions may be preferable in certain circumstances.


Assuntos
Pais , Pesquisa Qualitativa , Humanos , Adolescente , Feminino , Masculino , Pais/psicologia , Pessoal de Saúde/psicologia , Inglaterra , Cuidadores/psicologia , Transtornos Mentais/terapia , Transtornos Mentais/epidemiologia , Hospitalização/estatística & dados numéricos , Adulto , Pessoa de Meia-Idade , Pacientes Internados/psicologia , Admissão do Paciente
5.
Mol Psychiatry ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326559

RESUMO

White matter pathways, typically studied with diffusion tensor imaging (DTI), have been implicated in the neurobiology of obsessive-compulsive disorder (OCD). However, due to limited sample sizes and the predominance of single-site studies, the generalizability of OCD classification based on diffusion white matter estimates remains unclear. Here, we tested classification accuracy using the largest OCD DTI dataset to date, involving 1336 adult participants (690 OCD patients and 646 healthy controls) and 317 pediatric participants (175 OCD patients and 142 healthy controls) from 18 international sites within the ENIGMA OCD Working Group. We used an automatic machine learning pipeline (with feature engineering and selection, and model optimization) and examined the cross-site generalizability of the OCD classification models using leave-one-site-out cross-validation. Our models showed low-to-moderate accuracy in classifying (1) "OCD vs. healthy controls" (Adults, receiver operator characteristic-area under the curve = 57.19 ± 3.47 in the replication set; Children, 59.8 ± 7.39), (2) "unmedicated OCD vs. healthy controls" (Adults, 62.67 ± 3.84; Children, 48.51 ± 10.14), and (3) "medicated OCD vs. unmedicated OCD" (Adults, 76.72 ± 3.97; Children, 72.45 ± 8.87). There was significant site variability in model performance (cross-validated ROC AUC ranges 51.6-79.1 in adults; 35.9-63.2 in children). Machine learning interpretation showed that diffusivity measures of the corpus callosum, internal capsule, and posterior thalamic radiation contributed to the classification of OCD from HC. The classification performance appeared greater than the model trained on grey matter morphometry in the prior ENIGMA OCD study (our study includes subsamples from the morphometry study). Taken together, this study points to the meaningful multivariate patterns of white matter features relevant to the neurobiology of OCD, but with low-to-moderate classification accuracy. The OCD classification performance may be constrained by site variability and medication effects on the white matter integrity, indicating room for improvement for future research.

6.
Nutr. clín. diet. hosp ; 44(1): 254-260, Feb. 2024. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-231315

RESUMO

Antecedentes: El incumplimiento de la pensión de alimentos tiene un impacto negativo en la protección de la infancia, incrementando el riesgo de malnutrición e inseguridad alimentaria. Las relaciones familiares y la confianza en el sistema de justicia también se pueden ver afectadas.Objetivo: Describir las características de las deudas de pensión mensual de alimentos en Perú, según el área geográfica y la jurisdicción del órgano judicial.Materiales y métodos: Se desarrolló un estudio transversal mediante el análisis de los casos de deuda de pensión de alimentos del 2019, según el Registro de Deudores Alimentarios Morosos (REDAM) del Poder Judicial del Perú. Se realizó un análisis descriptivo de las deudas de pensión de alimentos por región y jurisdicción del órgano judicial.Resultados: Se incluyeron 750 registros de deudores de pensión de alimentos, y se identificó que solo 0.53% de los deudores subsano su deuda. Se encontraron diferencias entre las deudas de pensión de alimentos entre las regiones de Perú. Los indicadores de desarrollo humano y vulnerabilidad a la inseguridad alimentaria tuvieron una tendencia semejante que las pensiones de alimentos entre las regiones de Perú.Conclusión: Las deudas de pensión de alimentos se caracterizaron por provenir en mayor proporción de varones con trabajo, y se identificaron más casos de deudores en la sierra peruana.(AU)


Background: Noncompliance with child support paymentshas a negative impact on the protection of children, increas-ing the risk of malnutrition and food insecurity. Family rela-tionships and trust in the justice system can also be affected.Objective: To describe the characteristics of monthly childsupport debts in Peru, according to the geographic area andjurisdiction of the judicial authority.Materials and Methods: A cross-sectional study wasconducted by analyzing the cases of child support debt from2019, according to the Register of Delinquent Child SupportDebtors (REDAM) of the Judiciary of Peru. A descriptive analy-sis of child support debt by region and jurisdiction of the ju-dicial authority was carried out. Results: 750 records of child support debtors were in-cluded, and it was identified that only 0.53% of the debtorspaid off their debt. Differences were found in child supportdebt between the regions of Peru. Human development indi-cators and vulnerability to food insecurity had a similar trendas child support payments among the regions of Peru.Conclusion: Child support debts were characterized ascoming mostly from employed males, and more cases ofdebtors were identified in the Peruvian highlands.(AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Nutricionistas , Proteção da Criança , Nutrição da Criança , Direitos Humanos , Abastecimento de Alimentos , Estudos Transversais , Ciências da Nutrição , Peru
7.
Mol Psychiatry ; 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38195979

RESUMO

INTRODUCTION: Regional gray matter (GM) alterations have been reported in early-onset psychosis (EOP, onset before age 18), but previous studies have yielded conflicting results, likely due to small sample sizes and the different brain regions examined. In this study, we conducted a whole brain voxel-based morphometry (VBM) analysis in a large sample of individuals with EOP, using the newly developed ENIGMA-VBM tool. METHODS: 15 independent cohorts from the ENIGMA-EOP working group participated in the study. The overall sample comprised T1-weighted MRI data from 482 individuals with EOP and 469 healthy controls. Each site performed the VBM analysis locally using the standardized ENIGMA-VBM tool. Statistical parametric T-maps were generated from each cohort and meta-analyzed to reveal voxel-wise differences between EOP and healthy controls as well as the individual-based association between GM volume and age of onset, chlorpromazine (CPZ) equivalent dose, and other clinical variables. RESULTS: Compared with healthy controls, individuals with EOP showed widespread lower GM volume encompassing most of the cortex, with the most marked effect in the left median cingulate (Hedges' g = 0.55, p = 0.001 corrected), as well as small clusters of lower white matter (WM), whereas no regional GM or WM volumes were higher in EOP. Lower GM volume in the cerebellum, thalamus and left inferior parietal gyrus was associated with older age of onset. Deficits in GM in the left inferior frontal gyrus, right insula, right precentral gyrus and right superior frontal gyrus were also associated with higher CPZ equivalent doses. CONCLUSION: EOP is associated with widespread reductions in cortical GM volume, while WM is affected to a smaller extent. GM volume alterations are associated with age of onset and CPZ equivalent dose but these effects are small compared to case-control differences. Mapping anatomical abnormalities in EOP may lead to a better understanding of the role of psychosis in brain development during childhood and adolescence.

8.
Lancet Psychiatry ; 11(2): 143-154, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38071998

RESUMO

Psychopharmacological treatment is an important component of the multimodal intervention approach to treating mental health conditions in children and adolescents. Currently, there are many unmet needs but also opportunities, alongside possible risks to consider, regarding the pharmacological treatment of mental health conditions in children and adolescents. In this Position Paper, we highlight and address these unmet needs and opportunities, including the perspectives of clinicians and researchers from the European College of Neuropsychopharmacology-Child and Adolescent Network, alongside those of experts by lived experience from national and international associations, via a survey involving 644 participants from 13 countries, and of regulators, through representation from the European Medicines Agency. We present and discuss the evidence base for medications currently used for mental disorders in children and adolescents, medications in the pipeline, opportunities in the development of novel medications, crucial priorities for the conduct of future clinical studies, challenges and opportunities in terms of the regulatory and legislative framework, and innovations in the way research is conducted, reported, and promoted.


Assuntos
Transtornos Mentais , Psicofarmacologia , Adolescente , Humanos , Transtornos Mentais/tratamento farmacológico , Saúde Mental
9.
J Med Radiat Sci ; 71(1): 78-84, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37965811

RESUMO

INTRODUCTION: A standardised testing protocol for evaluation of a wide range of dental cone beam computed tomography (CBCT) performance and image quality (IQ) parameters is still limited and commercially available testing tool is unaffordable by some centres. This study aims to assess the performance of a low-cost fabricated phantom for image quality assessment (IQA) of digital CBCT unit. METHODS: A customised polymethyl methacrylate (PMMA) cylindrical phantom was developed for performance evaluation of Planmeca ProMax 3D Mid digital dental CBCT unit. The fabricated phantom consists of four different layers for testing specific IQ parameters such as CT number accuracy and uniformity, noise and CT number linearity. The phantom was scanned using common scanning protocols in clinical routine (90.0 kV, 8.0 mA and 13.6 s). In region-of-interest (ROI) analysis, the mean CT numbers (in Hounsfield unit, HU) and noise for water and air were determined and compared with the reference values (0 HU for water and -1000 HU for air). For linearity test, the correlation between the measured HU of different inserts with their density was studied. RESULTS: The average CT number were -994.1 HU and -2.4 HU, for air and water, respectively and the differences were within the recommended acceptable limit. The linearity test showed a strong positive correlation (R2 = 0.9693) between the measured HU and their densities. CONCLUSION: The fabricated IQ phantom serves as a simple and affordable testing tool for digital dental CBCT imaging.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Polimetil Metacrilato , Tomografia Computadorizada de Feixe Cônico/métodos , Imagens de Fantasmas , Água , Processamento de Imagem Assistida por Computador/métodos
10.
J Sleep Res ; 33(2): e14056, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37787462

RESUMO

Sleep problems are common for adolescents with psychiatric disorders, and sleep treatment may aid mental health recovery. Inpatient admissions are likely a particularly challenging time for sleep. Despite this little is known about the nature of sleep problems, and how sleep treatments could be optimised for this setting. This mixed-methods study set out to better understand sleep disturbances in adolescent inpatients. Study 1 examined the prevalence of Sleep Condition Indicator-assessed insomnia at admission and associations with psychiatric symptoms and admission length in 100 inpatients (aged 11-17 years) on one unit in Oxford. Data were gathered from admission routine measures and medical records. Associations were analysed using linear regressions. Half of the inpatients (n = 50) screened positive for insomnia at admission. Moderate-large significant associations were observed between more severe insomnia and more severe depression (ß = -0.56), anxiety (ß = -0.51), self-harm (ß = -0.49), psychotic experiences (ß = -0.32), and conduct problems (ß = -0.30), but not admission length. Study 2 gained 12 clinicians' perspectives on sleep problems on the unit via a focus group and semi-structured interviews, analysed using thematic analysis. Ward staff observed insomnia and excessive daytime sleepiness in adolescent inpatients and a reciprocal relationship with mental health symptoms. Ward processes were barriers (e.g., night-time observations) and facilitators (e.g., regular routines) of sleep. Cognitive behavioural therapy for insomnia was not routinely offered but viewed as potentially helpful. Insomnia may be a common problem for adolescent inpatients, associated with greater psychopathology, but not admission length. The possible benefits of psychological sleep interventions for adolescents admitted to psychiatric units now require testing.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Transtornos do Sono-Vigília , Humanos , Adolescente , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/terapia , Pacientes Internados/psicologia , Prevalência , Sono , Transtornos do Sono-Vigília/psicologia
11.
Eur J Clin Nutr ; 78(2): 155-162, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37923932

RESUMO

BACKGROUND: L-Leucine (Leu) supplementation may benefit fat-free mass (FFM) per se and glucose metabolism. OBJECTIVES: To determine whether Leu supplementation during energy restriction blunted the loss of FFM, enhanced the loss of fat mass (FM) and improved glucose tolerance. DESIGN: Thirty-seven adults, aged 20-65 years, with increased waist circumference and at least one other metabolic syndrome (MetS) component, were selected. We employed a two-arm parallel, double blind, randomized control trial (RCT) design. Participants were randomly assigned to an intervention group (leucine - 3 g/d) or placebo (lactose - 2.67 g/d), while following an individualised energy restricted diet for an 8-week period. Detailed body composition (DEXA), oral glucose tolerance test (OGTT), insulin and components of MetS were measured before and after the trial. Analysis of covariance (ANCOVA) assessed the effect of Leu on an intention-to-treat (ITT) principle. Bootstrapping method with 1000 bootstrap samples was used to derive parameter estimates, standard errors, p-values, and 95% confidence intervals for all outcomes. RESULTS: Adjusted for baseline values and other covariates, FFM (p = 0.045) and lean tissue mass (LTM) (p = 0.050) were significantly higher following Leu. These outcomes were modified by a significant treatment x sex interaction that indicated Leu had the greater effect in men. However, on adjustment for body composition changes, there was no difference in insulin sensitivity, oral glucose tolerance, or change in MetS components following Leu. CONCLUSION: Short-term leucine supplementation during energy restriction resulted in a greater preservation of FFM and LTM particularly in men, but did not impact glucose metabolism.


Assuntos
Síndrome Metabólica , Masculino , Adulto , Humanos , Leucina/farmacologia , Composição Corporal , Suplementos Nutricionais , Glucose
12.
BMJ Ment Health ; 26(1)2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097391

RESUMO

BACKGROUND: The increasing prevalence and acuity of mental disorders among children and adolescents have placed pressure on services, including inpatient care, and resulted in young people being admitted at-distance or to adult wards. Little empirical research has investigated such admissions. OBJECTIVE: To determine the incidence, clinical characteristics and 6-month outcomes of patients aged 13-17 years old admitted at-distance (>50 miles from home or out of region) to general adolescent psychiatric wards or to adult psychiatric wards. METHODS: Surveillance over 13 months (February 2021-February 2022) using the Child and Adolescent Psychiatry Surveillance System including baseline and 6-month follow-up questionnaires. FINDINGS: Data were collected about 290 admissions (follow-up rate 99% (288 of 290); sample were 73% female, mean age 15.8 years). The estimated adjusted yearly incidence of at-distance admission was 13.7-16.9 per 100 000 young people 13-17 years old. 38% were admitted >100 miles from home and 8% >200 miles. The most common diagnoses at referral were depression (34%) and autism spectrum disorder (20%); other common referral concerns included suicide risk (80%), emotional dysregulation (53%) and psychotic symptoms (22%). Over two-fifths (41%) waited ≥1 week for a bed, with 55% waiting in general hospital settings. At 6-month follow-up, 20% were still in hospital, the majority in at-distance placements. CONCLUSIONS: At-distance and adult ward admissions for patients aged <18 remain an ongoing challenge for healthcare provision and have an impact on acute hospital resource use. CLINICAL IMPLICATIONS: Long waits in non-specialist settings increase pressure across the healthcare system, highlighting the need to improve local service provision and commissioning to reflect identified clinical needs.


Assuntos
Transtorno do Espectro Autista , Transtornos Psicóticos , Adulto , Criança , Humanos , Adolescente , Feminino , Masculino , Pacientes Internados , Hospitalização , Hospitais Gerais
13.
Front Bioeng Biotechnol ; 11: 1261123, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965050

RESUMO

The field-testing and eventual adoption of genetically-engineered mosquitoes (GEMs) to control vector-borne pathogen transmission will require them meeting safety criteria specified by regulatory authorities in regions where the technology is being considered for use and other locales that might be impacted. Preliminary risk considerations by researchers and developers may be useful for planning the baseline data collection and field research used to address the anticipated safety concerns. Part of this process is to identify potential hazards (defined as the inherent ability of an entity to cause harm) and their harms, and then chart the pathways to harm and evaluate their probability as part of a risk assessment. The University of California Malaria Initiative (UCMI) participated in a series of workshops held to identify potential hazards specific to mosquito population modification strains carrying gene-drive systems coupled to anti-parasite effector genes and their use in a hypothetical island field trial. The hazards identified were placed within the broader context of previous efforts discussed in the scientific literature. Five risk areas were considered i) pathogens, infections and diseases, and the impacts of GEMs on human and animal health, ii) invasiveness and persistence of GEMs, and interactions of GEMs with target organisms, iii) interactions of GEMs with non-target organisms including horizontal gene transfer, iv) impacts of techniques used for the management of GEMs and v) evolutionary and stability considerations. A preliminary hazards list (PHL) was developed and is made available here. This PHL is useful for internal project risk evaluation and is available to regulators at prospective field sites. UCMI project scientists affirm that the subsequent processes associated with the comprehensive risk assessment for the application of this technology should be driven by the stakeholders at the proposed field site and areas that could be affected by this intervention strategy.

14.
Artigo em Inglês | MEDLINE | ID: mdl-37816603

RESUMO

Transposon-mediated transgenesis has revolutionized both basic and applied studies of mosquito vectors of disease. Currently, techniques such as enhancer traps and transposon tagging, which rely on remobilizable insertional mutagenesis, are only possible with transposon-based vector systems. Here, we provide general descriptions of methods and applications of transposon-based mosquito transgenesis. The exact procedures must be adapted to each mosquito species and comparisons of some differences among different mosquito species are outlined. A number of excellent publications showing detailed and specific protocols and methods are featured and referenced.

15.
Artigo em Inglês | MEDLINE | ID: mdl-37816607

RESUMO

Transposon-mediated transgenesis of mosquito vectors of disease pathogens followed the early success of transgenesis in the vinegar fly, Drosophila melanogaster The P transposable element used in Drosophila does not function canonically in mosquitoes, and repeatable, routine transgenesis in mosquitoes was not accomplished until new transposable elements were discovered and validated. A number of distinct transposons were subsequently identified that mediate the introduction of exogenous DNA in a stable and heritable manner in mosquito species, including members of the genera Aedes, Anopheles, and Culex The most versatile element, piggyBac, is functional in all of these mosquito genera, as well as in many other insects in diverse orders, and has been used extensively outside the class. Transposon-mediated transgenesis of recessive and dominant marker genes and reporter systems has been used to define functional fragments of gene control sequences, introduce exogenous DNA encoding products beneficial to medical interests, and act as "enhancer traps" to identify endogenous genes with specific expression characteristics.

16.
BMJ Case Rep ; 16(10)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907323

RESUMO

Laryngeal fractures are life-threatening injuries, frequently associated with long-term morbidity. We present a case of a man sustaining a displaced laryngeal fracture and rupture of supraglottic structures following attempted suicide by hanging from a bridge. His injuries included a tear of the thyrohyoid membrane, avulsed epiglottis and complete autopharyngotomy. All laryngeal functions were significantly impaired. Early tracheostomy, careful surgical repair, extensive multidisciplinary team (MDT) input and intensive rehabilitation all contributed towards a successful recovery. By 7 months following the initial injury, the patient had achieved excellent breathing and voicing, and a safe and competent swallow despite the extent of his initial injuries. This case demonstrates the importance of early airway management in laryngeal trauma and the role of surgical management in conjunction with swallow rehabilitation. Fundamentally, an MDT approach is essential for the holistic management of patients with laryngeal trauma.


Assuntos
Fraturas Ósseas , Laringe , Lesões do Pescoço , Masculino , Humanos , Laringe/cirurgia , Laringe/lesões , Traqueostomia , Fraturas Ósseas/cirurgia , Manuseio das Vias Aéreas , Epiglote , Lesões do Pescoço/complicações , Lesões do Pescoço/cirurgia
17.
BMC Biol ; 21(1): 194, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37704988

RESUMO

BACKGROUND: Worldwide invasion and expansion of Aedes albopictus, an important vector of dengue, chikungunya, and Zika viruses, has become a serious concern in global public health. Chemical insecticides are the primary means currently available to control the mosquito populations. However, long-term and large-scale use of insecticides has selected for resistance in the mosquito that is accompanied by a genetic load that impacts fitness. RESULTS: A number of laboratory strains representing different resistance mechanisms were isolated and identified from laboratory-derived, deltamethrin-resistant Ae. albopictus recovered in previous work. Resistance levels and fitness costs of the strains were evaluated and compared to characterize the evolution of the resistance genotypes and phenotypes. The heterozygous F1534S mutation (1534F/S) in the voltage gated sodium channel (vgsc) gene product (VGSC), first detected in early stages of resistance evolution, not only confers high-level resistance, but also produces no significant fitness costs, leading to the rapid spread of resistance in the population. This is followed by the increase in frequency of homozygous F1534S (1534S/S) mosquitoes that have significant fitness disadvantages, prompting the emergence of an unlinked I1532T mutation with fewer side effects and a mating advantage better adapted to the selection and reproductive pressures imposed in the experiments. Metabolic resistance with no significant fitness cost and mediating a high-tolerance resistance phenotype may play a dominant role in the subsequent evolution of resistance. The different resistant strains had similar vector competence for dengue virus type-2 (DENV-2). Furthermore, a comparative analysis of vectorial capacity revealed that increased survival due to deltamethrin resistance balanced the negative fitness cost effects and contributed to the risk of dengue virus (DENV) transmission by resistant populations. The progressive evolution of resistance results in mosquitoes with both target-site insensitivity and metabolic resistance with lower fitness costs, which further leads to resistant populations with both high resistance levels and vectorial capacity. CONCLUSIONS: This study reveals a possible mechanism for the evolution of deltamethrin resistance in Aedes albopictus. These findings will help guide practical strategies for insecticide use, resistance management and the prevention and control of mosquito-borne disease.


Assuntos
Aedes , Vírus da Dengue , Inseticidas , Infecção por Zika virus , Zika virus , Animais , Aedes/genética , Vírus da Dengue/genética , Inseticidas/farmacologia , Mosquitos Vetores/genética
18.
Proc Natl Acad Sci U S A ; 120(33): e2306322120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549256

RESUMO

Plants produce various pigments that not only appear as attractive colors but also provide valuable resources in applications in daily life and scientific research. Biosynthesis pathways for these natural plant pigments are well studied, and most have multiple enzymes that vary among plant species. However, adapting these pathways to animals remains a challenge. Here, we describe successful biosynthesis of betalains, water-soluble pigments found only in a single plant order, Caryophyllales, in transgenic silkworms by coexpressing three betalain synthesis genes, cytochrome P450 enzyme CYP76AD1, DOPA 4,5-dioxygenase, and betanidin 5-O-glucosyltransferase. Betalains can be synthesized in various tissues under the control of the ubiquitous IE1 promoter but accumulate mainly in the hemolymph with yields as high as 274 µg/ml. Additionally, transformed larvae and pupae show a strong red color easily distinguishable from wild-type animals. In experiments in which expression is controlled by the promoter of silk gland-specific gene, fibroin heavy-chain, betalains are found predominantly in the silk glands and can be secreted into cocoons through spinning. Betalains in transformed cocoons are easily recovered from cocoon shells in water with average yields reaching 14.4 µg/mg. These data provide evidence that insects can synthesize natural plant pigments through a complex, multiple enzyme-mediated synthesis pathway. Such pigments also can serve as dominant visible markers in insect transgenesis applications. This study provides an approach to producing valuable plant-derived compounds by using genetically engineered silkworms as a bioreactor.


Assuntos
Bombyx , Engenharia Genética , Animais Geneticamente Modificados , Animais , Pigmentos Biológicos/biossíntese , Betalaínas/biossíntese , Betalaínas/química , Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Cor
19.
Proc Natl Acad Sci U S A ; 120(29): e2221118120, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37428915

RESUMO

Proposed genetic approaches for reducing human malaria include population modification, which introduces genes into vector mosquitoes to reduce or prevent parasite transmission. We demonstrate the potential of Cas9/guide RNA (gRNA)-based gene-drive systems linked to dual antiparasite effector genes to spread rapidly through mosquito populations. Two strains have an autonomous gene-drive system coupled to dual anti-Plasmodium falciparum effector genes comprising single-chain variable fragment monoclonal antibodies targeting parasite ookinetes and sporozoites in the African malaria mosquitoes Anopheles gambiae (AgTP13) and Anopheles coluzzii (AcTP13). The gene-drive systems achieved full introduction within 3 to 6 mo after release in small cage trials. Life-table analyses revealed no fitness loads affecting AcTP13 gene-drive dynamics but AgTP13 males were less competitive than wild types. The effector molecules reduced significantly both parasite prevalence and infection intensities. These data supported transmission modeling of conceptual field releases in an island setting that shows meaningful epidemiological impacts at different sporozoite threshold levels (2.5 to 10 k) for human infection by reducing malaria incidence in optimal simulations by 50 to 90% within as few as 1 to 2 mo after a series of releases, and by ≥90% within 3 mo. Modeling outcomes for low sporozoite thresholds are sensitive to gene-drive system fitness loads, gametocytemia infection intensities during parasite challenges, and the formation of potentially drive-resistant genome target sites, extending the predicted times to achieve reduced incidence. TP13-based strains could be effective for malaria control strategies following validation of sporozoite transmission threshold numbers and testing field-derived parasite strains. These or similar strains are viable candidates for future field trials in a malaria-endemic region.


Assuntos
Anopheles , Malária Falciparum , Malária , Animais , Masculino , Humanos , Anopheles/genética , Anopheles/parasitologia , Mosquitos Vetores/genética , Malária/prevenção & controle , Plasmodium falciparum/genética , Esporozoítos , Malária Falciparum/parasitologia
20.
Arch Virol ; 168(6): 172, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37261601

RESUMO

Using high-throughput sequencing, we identified a novel carlavirus sequence in a 28-year-old 'Kotsifali' grapevine sample collected in Heraklion (Crete, Greece). Using RT-PCR and 5'/3' RACE together with Sanger sequencing, the complete genome sequence of 8299 nt was confirmed and found to contain five open reading frames (ORFs) but to lack an ORF6, which is present in some members of the genus Carlavirus. The novel sequence is most similar to those of two carlaviruses infecting caper, and taking into account the ICTV nomenclature, we propose the name "grapevine carlavirus 1" for this new virus.


Assuntos
Carlavirus , Vitis , Carlavirus/genética , Genoma Viral , Grécia , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Fases de Leitura Aberta , Doenças das Plantas
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