Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.166
Filtrar
1.
Eur J Cancer ; 205: 114103, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38729054

RESUMEN

BACKGROUND: PTEN loss and aberrations in PI3K/AKT signaling kinases associate with poorer response to abiraterone acetate (AA) in metastatic castration-resistant prostate cancer (mCRPC). In this study, we assessed antitumor activity of the AKT inhibitor capivasertib combined with enzalutamide in mCRPC with prior progression on AA and docetaxel. METHODS: This double-blind, placebo-controlled, randomized phase 2 trial, recruited men ≥ 18 years with progressing mCRPC and performance status 0-2 from 15 UK centers. Randomized participants (1:1) received enzalutamide (160 mg orally, once daily) with capivasertib (400 mg)/ placebo orally, twice daily on an intermittent (4 days on, 3 days off) schedule. Primary endpoint was composite response rate (RR): RECIST 1.1 objective response, ≥ 50 % PSA decrease from baseline, or circulating tumor cell count conversion (from ≥ 5 at baseline to < 5 cells/7.5 mL). Subgroup analyses by PTENIHC status were pre-planned. RESULTS: Overall, 100 participants were randomized (50:50); 95 were evaluable for primary endpoint (47:48); median follow-up was 43 months. RR were 9/47 (19.1 %) enzalutamide/capivasertib and 9/48 (18.8 %) enzalutamide/placebo (absolute difference 0.4 % 90 %CI -12.8 to 13.6, p = 0.58), with similar results in the PTENIHC loss subgroup. Irrespective of treatment, OS was significantly worse for PTENIHC loss (10.1 months [95 %CI: 4.6-13.9] vs 14.8 months [95 %CI: 10.8-18]; p = 0.02). Most common treatment-emergent grade ≥ 3 adverse events for the combination were diarrhea (13 % vs 2 %) and fatigue (10 % vs 6 %). CONCLUSIONS: Combined capivasertib/enzalutamide was well tolerated but didn't significantly improve outcomes from abiraterone pre-treated mCRPC.

2.
J Am Vet Med Assoc ; : 1-8, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38729208

RESUMEN

OBJECTIVE: To assess levels of burnout, well-being, and mental health of veterinarians and compare them to those of nonveterinarians by use of validated instruments, and to identify the predictive values of techniques individuals can use to help reduce burnout and/or improve well-being and mental health. SAMPLE: An online survey of 4,636 veterinarians from a random sample of 40,000 US veterinarians provided by the AVMA. METHODS: The study was fielded from September 11 to October 9, 2023. RESULTS: Burnout and well-being of veterinarians were generally consistent with that of employed US adults. Serious psychological distress was more common among veterinarians than in the general population. Veterinarians on average were more likely to score higher in neuroticism than nonveterinarians, and neuroticism was a predictor of low well-being, poor mental health, and burnout. Work-life balance, an effective coping mechanism for stress, and working in a positive clinic culture were among the significant factors that predicted good well-being and mental health and reduced burnout. CLINICAL RELEVANCE: The higher percentage than the norm of veterinarians with serious psychological distress was a concern. Focusing on maintaining a good work-life balance and adopting a reliable coping mechanism can potentially help reduce distress. Veterinary medicine is an inherently stressful profession. The purpose of this study was to identify key factors that contribute to burnout, well-being, and mental health and to determine what behaviors and management techniques help reduce stress and burnout and contribute to well-being and mental health, thus improving job satisfaction and personal fulfillment.

3.
JACC CardioOncol ; 6(2): 267-279, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38774021

RESUMEN

Background: Combination therapy with immune checkpoint inhibitors (ICIs) and vascular endothelial growth factor inhibitors (VEGFIs) has improved cancer outcomes and is increasingly used. These drug classes are associated with cardiovascular toxicities when used alone, but heterogeneity in trial design and reporting may limit knowledge of toxicities in patients receiving these in combination. Objectives: The aim of this study was to assess consistency and clarity in definitions and reporting of cardiovascular eligibility criteria, baseline characteristics, and cardiovascular adverse events in ICI and VEGFI combination trials. Methods: A scoping review was conducted of phase 2 to 4 randomized controlled trials of ICI and VEGFI combination therapy for solid tumors. Trial cardiovascular eligibility criteria and baseline cardiovascular characteristic reporting in trial publications was assessed, and cardiovascular adverse event definitions and reporting criteria were also examined. Results: Seventeen trials (N = 10,313; published 2018-2022) were included. There were multiple cardiovascular exclusion criteria in 15 trials. No primary trial publication reported baseline cardiovascular characteristics. Thirteen trials excluded patients with prior heart failure, myocardial infarction, hypertension, or stroke. There was heterogeneity in defining cardiovascular conditions. "Grade 1 to 4" cardiovascular adverse events were reported when incidence was ≥5% to 25% in 15 trials. Incident hypertension was recorded in all trials, but other cardiovascular events were not consistently reported. No trial specifically noted the absence of cardiovascular events. Conclusions: In ICI and VEGFI combination trials, there is heterogeneity in cardiovascular exclusion criteria, reporting of baseline characteristics, and reporting of cardiovascular adverse events. This limits an optimal understanding of the incidence and severity of events relating to these combinations. Better standardization of these elements should be pursued. (Exclusions and Representation of Patients With Kidney Disease and Cardiovascular Disease in Drug Trials of the Novel Systemic Anti-Cancer Therapies VEGF-Signalling Pathway Inhibitors Alone or in Combination With Immune Checkpoint Inhibitors; CRD42022337942).

5.
Mol Pharm ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717252

RESUMEN

Despite the increasing importance of aldehyde oxidase (AO) in the drug metabolism of clinical candidates, ontogeny data for AO are limited. The objective of our study was to characterize the age-dependent AO content and activity in the human liver cytosolic fraction (HLC) and human hepatocytes (HH). HLC (n = 121 donors) and HH (n = 50 donors) were analyzed for (1) AO protein content by quantitative proteomics and (2) enzyme activity using carbazeran as a probe substrate. AO activity showed high technical variability and poor correlation with the content in HLC samples, whereas hepatocyte samples showed a strong correlation between the content and activity. Similarly, AO content and activity showed no significant age-dependent differences in HLC samples, whereas the average AO content and activity in hepatocytes increased significantly (∼20-40-fold) from the neonatal levels (0-28 days). Based on the hepatocyte data, the age at which 50% of the adult AO content is reached (age50) was 3.15 years (0.32-13.97 years, 95% CI). Metabolite profiling of carbazeran revealed age-dependent metabolic switching and the role of non-AO mechanisms (glucuronidation and desmethylation) in carbazeran elimination. The content-activity correlation in hepatocytes improved significantly (R2 = 0.95; p < 0.0001) in samples showing <10% contribution of glucuronidation toward the overall metabolism, confirming that AO-mediated oxidation and glucuronidation are the key routes of carbazeran metabolism. Considering the confounding effect of glucuronidation on AO activity, AO content-based ontogeny data are a more direct reflection of developmental changes in protein expression. The comprehensive ontogeny data of AO in HH samples are more reliable than HLC data, which are important for developing robust physiologically based pharmacokinetic models for predicting AO-mediated metabolism in children.

6.
Inorg Chem ; 63(19): 8526-8530, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38696219

RESUMEN

Photoluminescent coordination complexes of Cr(III) are of interest as near-infrared spin-flip emitters. Here, we explore the preparation, electrochemistry, and photophysical properties of the first two examples of homoleptic N-heterocyclic carbene complexes of Cr(III), featuring 2,6-bis(imidazolyl)pyridine (ImPyIm) and 2-imidazolylpyridine (ImPy) ligands. The complex [Cr(ImPy)3]3+ displays luminescence at 803 nm on the microsecond time scale (13.7 µs) from a spin-flip doublet excited state, which transient absorption spectroscopy reveals to be populated within several picoseconds following photoexcitation. Conversely, [Cr(ImPyIm)2]3+ is nonemissive and has a ca. 500 ps excited-state lifetime.

8.
Eur J Protistol ; 94: 126083, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38640576

RESUMEN

The frequently encountered macroscopic slime molds of the genus Ceratiomyxa have long been recognized by mycologists and protistologists for hundreds of years. These organisms are amoebozoan amoebae that live and grow inside and on the surface of decaying wood. When conditions are favorable, they form subaerial sporulating structures called fruiting bodies which take on a variety of forms. These forms are typically some arrangement of column and/or branches, but one is uniquely poroid, forming folds instead. Originally, this poroid morphology was designated as its own species. However, it was not always clear what significance fruiting body morphology held in determining species. Currently, Ceratiomyxa fruticulosa var. porioides, the poroid form, is considered a taxonomic variety of Ceratiomyxa fruticulosa based on morphological designation alone. Despite its long history of observation and study, the genus Ceratiomyxa has been paid little molecular attention to alleviate these morphological issues. We have obtained the first transcriptomes of the taxon C. fruticulosa var. porioides and found single gene phylogenetic and multigene phylogenomic support to separate it from C. fruticulosa. This provides molecular evidence that fruiting body morphology does correspond to species level diversity. Therefore, we formally raise Ceratiomyxa porioides to species level.

9.
Anesthesiology ; 140(6): 1233-1234, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38558057
10.
bioRxiv ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38464291

RESUMEN

Lung cancer, the leading cause of cancer mortality, exhibits diverse histological subtypes and genetic complexities. Numerous preclinical mouse models have been developed to study lung cancer, but data from these models are disparate, siloed, and difficult to compare in a centralized fashion. Here we established the Lung Cancer Mouse Model Database (LCMMDB), an extensive repository of 1,354 samples from 77 transcriptomic datasets covering 974 samples from genetically engineered mouse models (GEMMs), 368 samples from carcinogen-induced models, and 12 samples from a spontaneous model. Meticulous curation and collaboration with data depositors have produced a robust and comprehensive database, enhancing the fidelity of the genetic landscape it depicts. The LCMMDB aligns 859 tumors from GEMMs with human lung cancer mutations, enabling comparative analysis and revealing a pressing need to broaden the diversity of genetic aberrations modeled in GEMMs. Accompanying this resource, we developed a web application that offers researchers intuitive tools for in-depth gene expression analysis. With standardized reprocessing of gene expression data, the LCMMDB serves as a powerful platform for cross-study comparison and lays the groundwork for future research, aiming to bridge the gap between mouse models and human lung cancer for improved translational relevance.

11.
Cancer Res ; 84(10): 1699-1718, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38535994

RESUMEN

There is an unmet need to improve the efficacy of platinum-based cancer chemotherapy, which is used in primary and metastatic settings in many cancer types. In bladder cancer, platinum-based chemotherapy leads to better outcomes in a subset of patients when used in the neoadjuvant setting or in combination with immunotherapy for advanced disease. Despite such promising results, extending the benefits of platinum drugs to a greater number of patients is highly desirable. Using the multiomic assessment of cisplatin-responsive and -resistant human bladder cancer cell lines and whole-genome CRISPR screens, we identified puromycin-sensitive aminopeptidase (NPEPPS) as a driver of cisplatin resistance. NPEPPS depletion sensitized resistant bladder cancer cells to cisplatin in vitro and in vivo. Conversely, overexpression of NPEPPS in sensitive cells increased cisplatin resistance. NPEPPS affected treatment response by regulating intracellular cisplatin concentrations. Patient-derived organoids (PDO) generated from bladder cancer samples before and after cisplatin-based treatment, and from patients who did not receive cisplatin, were evaluated for sensitivity to cisplatin, which was concordant with clinical response. In the PDOs, depletion or pharmacologic inhibition of NPEPPS increased cisplatin sensitivity, while NPEPPS overexpression conferred resistance. Our data present NPEPPS as a druggable driver of cisplatin resistance by regulating intracellular cisplatin concentrations. SIGNIFICANCE: Targeting NPEPPS, which induces cisplatin resistance by controlling intracellular drug concentrations, is a potential strategy to improve patient responses to platinum-based therapies and lower treatment-associated toxicities.


Asunto(s)
Cisplatino , Resistencia a Antineoplásicos , Neoplasias de la Vejiga Urinaria , Humanos , Cisplatino/farmacología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/metabolismo , Animales , Ratones , Línea Celular Tumoral , Aminopeptidasas/genética , Aminopeptidasas/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Antineoplásicos/farmacología , Organoides/efectos de los fármacos , Organoides/metabolismo
12.
Surgery ; 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38519408

RESUMEN

BACKGROUND: KRAS mutation is a negative prognostic factor for colorectal liver metastases. Several studies have investigated the resection margins according to KRAS status, with conflicting results. The aim of the study was to assess the oncologic outcomes of R0 and R1 resections for colorectal liver metastases according to KRAS status. METHODS: All patients who underwent resection for colorectal liver metastases between 2010 and 2015 with available KRAS status were enrolled in this multicentric international cohort study. Logistic regression models were used to investigate the outcomes of R0 and R1 colorectal liver metastases resections according to KRAS status: wild type versus mutated. The primary outcomes were overall survival and disease-free survival. RESULTS: The analysis included 593 patients. KRAS mutation was associated with shorter overall survival (40 vs 60 months; P = .0012) and disease-free survival (15 vs 21 months; P = .003). In KRAS-mutated tumors, the resection margin did not influence oncologic outcomes. In multivariable analysis, the only predictor of disease-free survival and overall survival was primary tumor location (P = .03 and P = .03, respectively). In KRAS wild-type tumors, R0 resection was associated with prolonged overall survival (74 vs 45 months, P < .001) and disease-free survival (30 vs 17 months, P < .001). The multivariable model confirmed that R0 resection margin was associated with prolonged overall survival (hazard ratio = 1.43, 95% confidence interval: 1.01-2.03) and disease-free survival (hazard ratio = 1.42; 95% confidence interval: 1.06-1.91). CONCLUSIONS: KRAS-mutated colorectal liver metastases showed more aggressive tumor biology with inferior overall survival and disease-free survival after liver resection. Although R0 resection was not associated with improved oncologic outcomes in the KRAS-mutated tumors group, it seems to be of paramount importance for achieving prolonged long-term survival in KRAS wild-type tumors.

14.
J Clin Oncol ; 42(13): 1466-1471, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38350047

RESUMEN

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.POUT was a phase III, randomized, open-label trial, including 261 patients with muscle-invasive or lymph node-positive, nonmetastatic upper tract urothelial cancer (UTUC) randomly assigned after radical nephroureterectomy to platinum-based chemotherapy (132) or surveillance (129). Primary outcome analysis demonstrated that chemotherapy improved disease-free survival (DFS). At that time, the planned secondary outcome analysis of overall survival (OS) was immature. By February 2022, 50 and 67 DFS events had occurred in the chemotherapy and surveillance groups, respectively, at a median follow-up of 65 months. The 5-year DFS was 62% versus 45%, univariable hazard ratio (HR), 0.55 (95% CI, 0.38 to 0.80, P = .001). The restricted mean survival time (RMST) was 18 months longer (95% CI, 6 to 30) in the chemotherapy arm. There were 46 and 60 deaths in the chemotherapy and control arms, respectively. The 5-year OS was 66% versus 57%, with univariable HR, 0.68 (95% CI, 0.46 to 1.00, P = .049) and RMST difference 11 months (95% CI, 1 to 21). Treatment effects were consistent across chemotherapy regimens (carboplatin or cisplatin) and disease stage. Toxicities were similar to those previously reported, and there were no clinically relevant differences in quality of life between arms. In summary, although OS was not the primary outcome measure, the updated results add further support for the use of adjuvant chemotherapy in patients with UTUC, suggesting long-term benefits.


Asunto(s)
Nefroureterectomía , Humanos , Nefroureterectomía/métodos , Quimioterapia Adyuvante , Femenino , Supervivencia sin Enfermedad , Masculino , Anciano , Persona de Mediana Edad , Carcinoma de Células Transicionales/tratamiento farmacológico , Carcinoma de Células Transicionales/mortalidad , Carcinoma de Células Transicionales/cirugía , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Urológicas/tratamiento farmacológico , Neoplasias Urológicas/mortalidad , Neoplasias Urológicas/cirugía , Neoplasias Urológicas/patología , Neoplasias Ureterales/tratamiento farmacológico , Neoplasias Ureterales/mortalidad , Neoplasias Ureterales/cirugía , Neoplasias Ureterales/patología , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/mortalidad , Neoplasias Renales/cirugía , Neoplasias Renales/patología
15.
NEJM Evid ; 3(1): EVIDoa2300171, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38320513

RESUMEN

Targeted Inhibition of CYP11A1 in Prostate CancerIn this single-arm, multicenter, combined phase 1 and phase 2 study, patients with metastatic prostate adenocarcinoma with progression on prior androgen receptor pathway inhibitors and taxane-based chemotherapy were treated with ODM-208. A decrease in prostate-specific antigen levels of 50% or more occurred in 16/42 (38.1%) and 24/45 (53.3%) in phase 1 and 2 respectively. Responses mainly occurred in patients with androgen receptor mutations. Adrenal insufficiency was the dose-limiting toxicity.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Receptores Androgénicos , Masculino , Humanos , Receptores Androgénicos/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol , Antígeno Prostático Específico/uso terapéutico , Resultado del Tratamiento , Antagonistas de Receptores Androgénicos/farmacología
16.
Nat Cancer ; 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355776

RESUMEN

Pancreatic ductal adenocarcinoma is a highly metastatic disease and macrophages support liver metastases. Efferocytosis, or engulfment of apoptotic cells by macrophages, is an essential process in tissue homeostasis and wound healing, but its role in metastasis is less well understood. Here, we found that the colonization of the hepatic metastatic site is accompanied by low-grade tissue injury and that efferocytosis-mediated clearance of parenchymal dead cells promotes macrophage reprogramming and liver metastasis. Mechanistically, progranulin expression in macrophages is necessary for efficient efferocytosis by controlling lysosomal acidification via cystic fibrosis transmembrane conductance regulator and the degradation of lysosomal cargo, resulting in LXRα/RXRα-mediated macrophage conversion and upregulation of arginase 1. Pharmacological blockade of efferocytosis or macrophage-specific genetic depletion of progranulin impairs macrophage conversion, improves CD8+ T cell functions, and reduces liver metastasis. Our findings reveal how hard-wired functions of macrophages in tissue repair contribute to liver metastasis and identify potential targets for prevention of pancreatic ductal adenocarcinoma liver metastasis.

17.
Trop Med Infect Dis ; 9(2)2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38393132

RESUMEN

Colombia has a tropical climate and environmental conditions that favour the circulation of most of the known vector-borne diseases (VBDs). Protocols have been established and implemented to address the threats of these diseases, but they are for country-wide use and do not take into consideration the nuances of the different environments of the country. Almost the entire population is vulnerable to infection with one or more VBD. This study aims to characterise the perceptions and experiences of stakeholders involved in vector control and VBDs in the Orinoquia region in Colombia. Two panel discussions, and 12 semi-structured interviews, were conducted. Experts from the Colombian National Health Institute (INS), health secretaries from Meta, Guaviare and Vichada Departments, academic researchers, and individuals from private vector control companies participated. All sessions were recorded, transcribed, and translated, and then subject to thematic analysis. Three major themes emerged: involvement, limitations, and recommendations. Results showed that participants are engaged in vector surveillance activities, education, and vector control research. Participants focused on problems of disjointed efforts towards VBD control between health secretaries and the health ministry, as well as societal issues, such as socioeconomic, cultural, and political issues, which became the rationale for the lack of vector control resources. Responses in the panel discussions and interviews overlapped in opinions, and suggested that vector control could be improved through better communication between vector control bodies, strengthened engagement with vulnerable communities, more collaborative actions, and a more balanced distribution of resources.

18.
J Eukaryot Microbiol ; 71(3): e13020, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38240465

RESUMEN

Biological soil crusts represent a rich habitat for diverse and complex eukaryotic microbial communities. A unique but extremely common habitat is the urban sidewalk and its cracks that collect detritus. While these habitats are ubiquitous across the globe, little to no work has been conducted to characterize protists found there. Amoeboid protists are major predators of bacteria and other microbial eukaryotes in these microhabitats and therefore play a substantial ecological role. From sidewalk crack soil crusts, we have isolated three naked amoebae with finely tapered subpseudopodia, and a simple life cycle consisting of a trophic amoeba and a cyst stage. Using a holistic approach including light, electron, and fluorescence microscopy as well as phylogenetics using the ribosomal small subunit rRNA gene and phylogenomics using 230 nuclear genes, we find that these amoeboid organisms fail to match any previously described eukaryote genus. However, we determined the amoebae belong to the amoebozoan lineage Variosea based on phylogenetics. The molecular analyses place our isolates in two novel genera forming a grade at the base of the variosean group Protosteliida. These three novel varioseans among two novel genera and species are herein named "Kanabo kenzan" and "Parakanabo toge."


Asunto(s)
Amebozoos , Filogenia , Amebozoos/clasificación , Amebozoos/genética , Amebozoos/aislamiento & purificación , Suelo/parasitología , Ecosistema , ADN Protozoario/genética , Ciudades
19.
Sci Rep ; 14(1): 2033, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263350

RESUMEN

Rapid expansion of the pulmonary microvasculature through angiogenesis drives alveolarization, the final stage of lung development that occurs postnatally and dramatically increases lung gas-exchange surface area. Disruption of pulmonary angiogenesis induces long-term structural and physiologic lung abnormalities, including bronchopulmonary dysplasia, a disease characterized by compromised alveolarization. Although endothelial cells are primary determinants of pulmonary angiogenesis, mesenchymal cells (MC) play a critical and dual role in angiogenesis and alveolarization. Therefore, we performed single cell transcriptomics and in-situ imaging of the developing lung to profile mesenchymal cells during alveolarization and in the context of lung injury. Specific mesenchymal cell subtypes were present at birth with increasing diversity during alveolarization even while expressing a distinct transcriptomic profile from more mature correlates. Hyperoxia arrested the transcriptomic progression of the MC, revealed differential cell subtype vulnerability with pericytes and myofibroblasts most affected, altered cell to cell communication, and led to the emergence of Acta1 expressing cells. These insights hold the promise of targeted treatment for neonatal lung disease, which remains a major cause of infant morbidity and mortality across the world.


Asunto(s)
Displasia Broncopulmonar , Hiperoxia , Células Madre Mesenquimatosas , Recién Nacido , Lactante , Humanos , Células Endoteliales , Pulmón
20.
Parasit Vectors ; 17(1): 10, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38178249

RESUMEN

BACKGROUND: Insecticide resistance is reducing the efficacy of vector control interventions, consequently threatening efforts to control vector-borne diseases, including malaria. Investigating the prevalence of molecular markers of resistance is a useful tool for monitoring the spread of insecticide resistance in disease vectors. The Bijagós Archipelago (Bijagós) in Guinea-Bissau is a region of stable malaria transmission where insecticide-treated nets are the mainstay for malaria control. However, the prevalence of molecular markers of insecticide resistance in malaria vectors is not well understood. METHODS: A total of 214 Anopheles mosquitoes were analysed from 13 islands across the Bijagós. These mosquitoes were collected using CDC light traps in November 2019, during the peak malaria transmission season. High-throughput multiplex amplicon sequencing was used to investigate the prevalence of 17 different molecular markers associated with insecticide resistance in four genes: vgsc, rdl, ace1 and gste2. RESULTS: Of the 17 screened mutations, four were identified in mosquitoes from the Bijagós: vgsc L995F (12.2%), N1570Y (6.2%) and A1746S (0.7%) and rdl A269G (1.1%). This study is the first to report the L995F knock-down resistance (kdr)-west allele in Anopheles melas on the Archipelago. An additional eight non-synonymous single-nucleotide polymorphisms were identified across the four genes which have not been described previously. The prevalences of the vgsc L995F and N1570Y mutations were higher on Bubaque Island than on the other islands in this study; Bubaque is the most populous island in the archipelago, with the greatest population mobility and connection to continental Guinea-Bissau. CONCLUSIONS: This study provides the first surveillance data for genetic markers present in malaria vectors from islands across the Bijagós Archipelago. Overall prevalence of insecticide resistance mutations was found to be low. However, the identification of the vgsc L995F and N1570Y mutations associated with pyrethroid resistance warrants further monitoring. This is particularly important as the mainstay of malaria control on the islands is the use of pyrethroid insecticide-treated nets.


Asunto(s)
Anopheles , Insecticidas , Malaria , Piretrinas , Animales , Anopheles/genética , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Mosquitos Vectores/genética , Piretrinas/farmacología , Genómica , Mutación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...