Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 292
Filtrar
Más filtros

Intervalo de año de publicación
1.
Nature ; 633(8031): 848-855, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39143210

RESUMEN

Bread wheat (Triticum aestivum) is a globally dominant crop and major source of calories and proteins for the human diet. Compared with its wild ancestors, modern bread wheat shows lower genetic diversity, caused by polyploidisation, domestication and breeding bottlenecks1,2. Wild wheat relatives represent genetic reservoirs, and harbour diversity and beneficial alleles that have not been incorporated into bread wheat. Here we establish and analyse extensive genome resources for Tausch's goatgrass (Aegilops tauschii), the donor of the bread wheat D genome. Our analysis of 46 Ae. tauschii genomes enabled us to clone a disease resistance gene and perform haplotype analysis across a complex disease resistance locus, allowing us to discern alleles from paralogous gene copies. We also reveal the complex genetic composition and history of the bread wheat D genome, which involves contributions from genetically and geographically discrete Ae. tauschii subpopulations. Together, our results reveal the complex history of the bread wheat D genome and demonstrate the potential of wild relatives in crop improvement.


Asunto(s)
Aegilops , Pan , Productos Agrícolas , Evolución Molecular , Genoma de Planta , Triticum , Aegilops/genética , Alelos , Productos Agrícolas/genética , Resistencia a la Enfermedad/genética , Domesticación , Genes de Plantas/genética , Variación Genética/genética , Genoma de Planta/genética , Haplotipos/genética , Filogenia , Fitomejoramiento , Enfermedades de las Plantas/genética , Poliploidía , Triticum/genética
2.
BMC Biol ; 22(1): 13, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273258

RESUMEN

BACKGROUND: Single-nucleotide polymorphisms (SNPs) are the most widely used form of molecular genetic variation studies. As reference genomes and resequencing data sets expand exponentially, tools must be in place to call SNPs at a similar pace. The genome analysis toolkit (GATK) is one of the most widely used SNP calling software tools publicly available, but unfortunately, high-performance computing versions of this tool have yet to become widely available and affordable. RESULTS: Here we report an open-source high-performance computing genome variant calling workflow (HPC-GVCW) for GATK that can run on multiple computing platforms from supercomputers to desktop machines. We benchmarked HPC-GVCW on multiple crop species for performance and accuracy with comparable results with previously published reports (using GATK alone). Finally, we used HPC-GVCW in production mode to call SNPs on a "subpopulation aware" 16-genome rice reference panel with ~ 3000 resequenced rice accessions. The entire process took ~ 16 weeks and resulted in the identification of an average of 27.3 M SNPs/genome and the discovery of ~ 2.3 million novel SNPs that were not present in the flagship reference genome for rice (i.e., IRGSP RefSeq). CONCLUSIONS: This study developed an open-source pipeline (HPC-GVCW) to run GATK on HPC platforms, which significantly improved the speed at which SNPs can be called. The workflow is widely applicable as demonstrated successfully for four major crop species with genomes ranging in size from 400 Mb to 2.4 Gb. Using HPC-GVCW in production mode to call SNPs on a 25 multi-crop-reference genome data set produced over 1.1 billion SNPs that were publicly released for functional and breeding studies. For rice, many novel SNPs were identified and were found to reside within genes and open chromatin regions that are predicted to have functional consequences. Combined, our results demonstrate the usefulness of combining a high-performance SNP calling architecture solution with a subpopulation-aware reference genome panel for rapid SNP discovery and public deployment.


Asunto(s)
Genoma de Planta , Polimorfismo de Nucleótido Simple , Flujo de Trabajo , Fitomejoramiento , Programas Informáticos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos
3.
J Infect Dis ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39255068

RESUMEN

BACKGROUND: Blood biomarkers of neurological injury could provide a rapid diagnosis of central nervous system (CNS) injury caused by infections. An FDA-approved assay for mild traumatic brain injury (TBI) measures glial fibrillary acidic protein (GFAP) and ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), which signal astrocyte and neuronal injury, respectively. Here, we assessed the applicability of this biomarker assay for determining infection-induced brain injury. METHODS: We measured serum levels of GFAP and UCH-L1 retrospectively in serum samples from three study populations: 1) human cases infected with Venezuelan equine encephalitis virus (VEEV) and Madariaga virus (MADV) (n = 73), 2) human sepsis patients who were severely ill or diagnosed with encephalitis (n = 66), and 3) sepsis cases that were subsequently evaluated for cognitive impairment (n = 64). RESULTS: In the virus infection group, we found elevated GFAP for VEEV (p = 0.014) and MADV (p = 0.011) infections, which correlated with seizures (p = 0.006). In the bacterial sepsis group, GFAP was elevated in cases diagnosed with encephalitis (p = 0.0007) and correlated with headaches (p = 0.0002). In the bacterial sepsis cases with a later cognitive assessment, elevated GFAP (p = 0.0057) at study enrollment was associated with cognitive impairment six months later with a positive prognostic capacity of 79% (CI: 66-95%; p = 0.0068). CONCLUSIONS: GFAP and UCH-L1 levels measured using an FDA-approved assay for TBI may indicate brain injury resulting from viral or bacterial infections and could predict the development of neurological sequelae.

4.
J Infect Dis ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38682569

RESUMEN

BACKGROUND: We explored the impact of prior Yellow fever (YF) or Japanese encephalitis (JE) vaccination on the efficacy of Takeda's dengue vaccine candidate, TAK-003 (NCT02747927). METHODS: Children 4-16 years of age were randomized 2:1 to receive TAK-003 or placebo and were under active febrile surveillance. Symptomatic dengue was confirmed by serotype-specific RT-PCR. YF and JE vaccination history was recorded. RESULTS: Of the 20,071 children who received TAK-003 or placebo, 21.1% had a YF and 23.9% had a JE vaccination history at randomization. Fifty-seven months after vaccination, vaccine efficacy was 55.7% (95% CI, 39.7%-67.5%) in those with YF vaccination, 77.8% (70.8%-83.1%) for JE vaccination, and 53.5% (45.4%-60.4%) for no prior YF/JE vaccination. Regional differences in serotype distribution confound these results. The apparent higher vaccine efficacy in the JE vaccination subgroup could be largely explained by serotype-specific efficacy of TAK-003. Within 28 days of any vaccination, the proportions of participants with serious adverse events in the YF/JE prior vaccination population were comparable between the TAK-003 and placebo groups. CONCLUSIONS: The available data do not suggest a clinically relevant impact of prior JE or YF vaccination on TAK-003 performance. Overall, TAK-003 was well-tolerated and efficacious in different epidemiological settings.

5.
Clin Infect Dis ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38995684

RESUMEN

BACKGROUND: Dengue is an increasing threat to global health. This exploratory analysis evaluated the immunogenicity, safety, and vaccine efficacy (VE) of a live-attenuated tetravalent dengue vaccine (TAK-003) in participants enrolled in the phase 3 DEN-301 trial (NCT02747927), stratified by baseline age (4-5 years; 6-11 years; or 12-16 years). METHODS: Participants were randomized 2:1 to receive 2 doses of TAK-003, administered 3 months apart, or placebo. Dengue serostatus was evaluated at enrolment. VE against virologically-confirmed dengue (VCD) and hospitalized VCD; immunogenicity (geometric mean titers; GMTs); and safety were evaluated per age group through ∼4 years post-vaccination. RESULTS: VE against VCD across serotypes was 43.5% (95% confidence interval: 25.3%, 57.3%) for 4-5 year-olds; 63.5% (56.9%, 69.1%) for 6-11 year-olds, and 67.7% (57.8%, 75.2%) for 12-16 year-olds. VE against hospitalized VCD was 63.8% (21.1%, 83.4%), 85.1% (77.1%, 90.3%), and 89.7% (77.9%, 95.2%), for the three age groups, respectively. GMTs remained elevated against all four serotypes for ∼4 years post-vaccination, with no evident differences across age groups. No clear differences in safety by age were identified. CONCLUSIONS: This exploratory analysis shows TAK-003 was efficacious in dengue prevention across age groups in children and adolescents 4-16 years of age living in dengue endemic areas. Relatively lower VE in 4-5 year-olds was potentially confounded by causative serotype distribution, small sample size, and VE by serotype, and should be considered in benefit-risk evaluations in this age group.

6.
Appl Microbiol Biotechnol ; 108(1): 106, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38217255

RESUMEN

Glioblastoma is one of the most lethal tumors, displaying striking cellular heterogeneity and drug resistance. The prognosis of patients suffering from glioblastoma after 5 years is only 5%. In the present work, capsaicin analogues bearing modifications on the acyl chain with long-chain fatty acids showed promising anti-tumoral activity by its cytotoxicity on U-87 and U-138 glioblastoma multiforme cells. The capsaicin analogues were enzymatically synthetized with cross-linked enzyme aggregates of lipase B from Candida antarctica (CALB). The catalytic performance of recombinant CALB-CLEAs was compared to their immobilized form on a hydrophobic support. After 72 h of reaction, the synthesis of capsaicin analogues from linoleic acid, docosahexaenoic acid, and punicic acid achieved a maximum conversion of 69.7, 8.3 and 30.3% with CALB-CLEAs, respectively. Similar values were obtained with commercial CALB, with conversion yields of 58.3, 24.2 and 22% for capsaicin analogues from linoleic acid, DHA and punicic acid, respectively. Olvanil and dohevanil had a significant cytotoxic effect on both U-87 and U-138 glioblastoma cells. Irrespective of the immobilization form, CALB is an efficient biocatalyst for the synthesis of anti-tumoral capsaicin derivatives. KEY POINTS: • This is the first report concerning the enzymatic synthesis of capsaicin analogues from docosahexaenoic acid and punicic acid with CALB-CLEAs. • The viability U-87 and U-138 glioblastoma cells was significantly affected after incubation with olvanil and dohevanil. • Capsaicin analogues from fatty acids obtained by CALB-CLEAs are promising candidates for therapeutic use as cytotoxic agents in glioblastoma cancer cells.


Asunto(s)
Capsaicina , Glioblastoma , Humanos , Capsaicina/farmacología , Enzimas Inmovilizadas/metabolismo , Glioblastoma/tratamiento farmacológico , Proteínas Fúngicas/metabolismo
7.
J Clin Microbiol ; 61(12): e0015223, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-37982611

RESUMEN

Eastern equine encephalitis virus (EEEV), Madariaga virus (MADV), and Venezuelan equine encephalitis virus complex (VEEV) are New World alphaviruses transmitted by mosquitoes. They cause febrile and sometimes severe neurological diseases in human and equine hosts. Detecting them during the acute phase is hindered by non-specific symptoms and limited diagnostic tools. We designed and clinically assessed real-time reverse transcription polymerase chain reaction assays (rRT-PCRs) for VEEV complex, MADV, and EEEV using whole-genome sequences. Validation involved 15 retrospective serum samples from 2015 to 2017 outbreaks, 150 mosquito pools from 2015, and 118 prospective samples from 2021 to 2022 surveillance in Panama. The rRT-PCRs detected VEEV complex RNA in 10 samples (66.7%) from outbreaks, with one having both VEEV complex and MADV RNAs. VEEV complex RNA was found in five suspected dengue cases from disease surveillance. The rRT-PCR assays identified VEEV complex RNA in three Culex (Melanoconion) vomerifer pools, leading to VEEV isolates in two. Phylogenetic analysis revealed the VEEV ID subtype in positive samples. Notably, 11.9% of dengue-like disease patients showed VEEV infections. Together, our rRT-PCR validation in human and mosquito samples suggests that this method can be incorporated into mosquito and human encephalitic alphavirus surveillance programs in endemic regions.


Asunto(s)
Alphavirus , Culicidae , Dengue , Virus de la Encefalitis Equina del Este , Encefalomielitis Equina Oriental , Encefalomielitis Equina Venezolana , Humanos , Animales , Caballos/genética , Virus de la Encefalitis Equina del Este/genética , Encefalomielitis Equina Venezolana/diagnóstico , Encefalomielitis Equina Venezolana/epidemiología , Culicidae/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Filogenia , Estudios Prospectivos , Vigilancia en Salud Pública , Estudios Retrospectivos , Alphavirus/genética , ARN
8.
Virol J ; 20(1): 302, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-38115118

RESUMEN

Parechovirus A (PeV-A, Parechovirus, Picornaviridae) are human pathogens associated with mild to severe gastrointestinal and respiratory diseases in young children. While several studies have investigated the association of PeV-A with human disease, little is known about its epidemiology or detection in Latin America. Between the years 2014 and 2015, a total of 200 samples were collected from Panamanian pediatric patients aged < 16 years old exhibiting symptoms associated with respiratory (n = 64), gastrointestinal (n = 68), or neurological (n = 68) diseases. These samples were gathered from patients who had previously received negative diagnoses for the main respiratory viruses, rotavirus, and neurological viruses like herpes virus, enterovirus, and cytomegalovirus. The presence of PeV-A was analyzed by real time RT-PCR.Eight positive PeV-A infections (4.0%, 95% CI: 1.7 to 7.7) were detected: two in respiratory samples (3.0%, 95% CI: 0.3 to 10.8), five in gastrointestinal samples (7.3%, 95% CI: 2.4 to 16.3), and one in cerebrospinal fluid (1.5%, 95% CI: 1.4 to 7.9). The study provides evidence of PeV-A circulation in Panama and the data collectively, remarked on the importance of considering PeV-A in the Panamanian pediatric diagnostic landscape, especially when conventional testing for more common viruses yields negative results.


Asunto(s)
Infecciones por Enterovirus , Enterovirus , Parechovirus , Infecciones por Picornaviridae , Picornaviridae , Humanos , Niño , Lactante , Preescolar , Adolescente , Parechovirus/genética , Infecciones por Picornaviridae/diagnóstico , Infecciones por Picornaviridae/epidemiología , Infecciones por Enterovirus/diagnóstico , Infecciones por Enterovirus/epidemiología , Picornaviridae/genética
9.
Cogn Psychol ; 143: 101575, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37229979

RESUMEN

Early emerging nonsymbolic proportional skills have been posited as a foundational ability for later fraction learning. A positive relation between nonsymbolic and symbolic proportional reasoning has been reported, as well as successful nonsymbolic training and intervention programs enhancing fraction magnitude skills. However, little is known about the mechanisms underlying this relationship. Of particular interest are nonsymbolic representations, which can be in continuous formats that may emphasize proportional relations and in discretized formats that may prompt erroneous whole-number strategies and hamper access to fraction magnitudes. We assessed the proportional comparison skills of 159 middle-school students (mean age = 12.54 years, 43% females, 55% males, 2% other or prefer not to say) across three types of representations: (a) continuous, unsegmented bars, (b) discretized, segmented bars that allowed counting strategies, and (c) symbolic fractions. Using both correlational and cluster approaches, we also examined their relations to symbolic fraction comparison ability. Within each stimulus type, we varied proportional distance, and in the discretized and symbolic stimuli, we also manipulated whole-number congruency. We found that fraction distance across all formats modulated middle-schoolers' performance; however, whole-number information affected discretized and symbolic comparison performance. Further, continuous and discretized nonsymbolic performance was related to fraction comparison ability; however, discretized skills explained variance above and beyond the contributions of continuous skills. Finally, our cluster analyses revealed three nonsymbolic comparison profiles: students who chose the bars with the largest number of segments (whole-number bias), chance-level performers, and high performers. Crucially, students with a whole-number bias profile showed this bias in their fraction skills and failed to show any symbolic distance modulation. Together, our results indicate that the relation between nonsymbolic and symbolic proportional skills may be determined by the (mis)conceptions based on discretized representations, rather than understandings of proportional magnitudes, suggesting that interventions focusing on competence with discretized representations may show dividends for fraction understanding.


Asunto(s)
Aprendizaje , Solución de Problemas , Masculino , Femenino , Humanos , Niño , Matemática , Análisis por Conglomerados , Logro
10.
Soft Matter ; 19(15): 2726-2736, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36974942

RESUMEN

The digital alchemy framework is an extended ensemble simulation technique that incorporates particle attributes as thermodynamic variables, enabling the inverse design of colloidal particles for desired behavior. Here, we extend the digital alchemy framework for the inverse design of patchy spheres that self-assemble into target crystal structures. To constrain the potentials to non-trivial solutions, we conduct digital alchemy simulations with constant second virial coefficient. We optimize the size, range, and strength of patchy interactions in model triblock Janus spheres to self-assemble the 2D kagome and snub square lattices and the 3D pyrochlore lattice, and demonstrate self-assembly of all three target structures with the designed models. The particles designed for the kagome and snub square lattices assemble into high quality clusters of their target structures, while competition from similar polymorphs lower the yield of the pyrochlore assemblies. We find that the alchemically designed potentials do not always match physical intuition, illustrating the ability of the method to find nontrivial solutions to the optimization problem. We identify a window of second virial coefficients that result in self-assembly of the target structures, analogous to the crystallization slot in protein crystallization.

11.
Clin Transplant ; 37(6): e14972, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36943871

RESUMEN

BACKGROUND: Despite the improvements in supportive care for allogeneic-hematopoietic cell transplantation (allo-HCT) recipients, infectious complications and infection-related mortality (IRM) continue to be a major issue for transplantation centers. METHODS: We herein report the infectious complications and IRM of 107 and 89 patients that underwent haploidentical (haplo-HCT) or HLA-identical HCT at a tertiary referral center during 2013-2020. Patients in the haplo-HCT group received post-transplant cyclophosphamide (PT-Cy), and all received reduced-intensity conditioning regimens. RESULTS: More haplo-HCT recipients presented severe infections in the pre-engraftment period (22.4% vs. 6.7%, p = 0.003). Viral (14.9% vs. 4.5%, p = 0.016) and fungal (12.1% vs. 1.1%, p = 0.003) etiologies were more common in this period in this group. The 100-day and 2-year cumulative incidence of IRM was 15% and 21% for the haplo-HCT and 5.6% and 17% for the HLA-identical group; no significant differences were observed between the groups. Fungal pathogens mainly contributed to IRM (33.3%). Infections were the most common cause of mortality (40/81, 49.4%). There were significant differences in donor/recipient CMV serostatus between transplant groups (0.002). CONCLUSIONS: No differences in IRM were observed based on allo-HCT type, with more haplo-HCT patients suffering from severe infections in the pre-engraftment period. Studies to assess future prevention, diagnostic, and treatment strategies to reduce IRM are warranted.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Humanos , Pacientes Ambulatorios , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Ciclofosfamida , Donantes de Tejidos , Acondicionamiento Pretrasplante , Estudios Retrospectivos
12.
Artículo en Inglés | MEDLINE | ID: mdl-36972089

RESUMEN

OBJECTIVES: Black Americans use identity-based self-protective strategies to maintain their explicit self-esteem after a threat to their intelligence. This effect is consistent with the associative-propositional evaluation (APE) model, which suggests that self-protective strategies operate during a propositional process that results in no change in explicit self-esteem. However, the APE model also suggests that implicit self-esteem may be sensitive to an intelligence threat because it increases the accessibility of automatically activated evaluations about Black Americans, namely the stereotype that their group is unintelligent. These hypotheses are tested across two experiments. METHOD: Black American participants across both experiments (Experiment 1: N = 57; 40 females, Mage = 21.60; Experiment 2: N = 79; 64 females, Mage = 24.86) completed an intelligence test, then were randomly assigned to receive either negative feedback about their performance or no-feedback. Participants then completed measures of implicit and explicit self-esteem. Participants in Experiment 2 also completed a measure of subjective identity centrality. RESULTS: In support of the hypotheses, Black American participants across both experiments who received negative performance feedback on an intelligence test exhibited lower implicit self-esteem compared to those who did not receive feedback. Experiment 2 further demonstrated that this effect emerged only among strongly identified Black American participants. Finally, and consistent with past research, explicit self-esteem was unaffected by negative performance feedback among all participants. CONCLUSIONS: This research demonstrates the boundary conditions of Black Americans' adoption of identity-based self-protective strategies to protect their implicit versus explicit self-esteem following an intelligence threat. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

13.
Artículo en Inglés | MEDLINE | ID: mdl-37326531

RESUMEN

OBJECTIVES: Faculty mentorship can be one solution to addressing the participation and persistence gaps between underrepresented groups (URGs) and overrepresented group members in science, technology, engineering, and math (STEM). However, little is known about the mechanisms underlying effective STEM faculty mentorship. The present study (a) investigates if faculty mentorship impacts STEM identity, attitudes, belonging, and self-efficacy; (b) compares students' perceptions of women versus men faculty mentorship support functions; and (c) uncovers the mentorship support mechanisms underlying impactful faculty mentorship. METHOD: The present research sampled ethnic-racial minority URG undergraduate students pursuing STEM majors across eight institutions (N = 362; age = 24.85; 36.6% Latinx, 30.6% Black, and 4.6% multiracial; 60.1% women). The study's overall quasi-experimental design adopted a one-factor two-level (faculty mentorship status: yes, no) between-subjects design. Among the participants who reported having a faculty mentor, we also examined faculty mentor gender (women vs. men) as a between-subjects variable. RESULTS: Faculty mentorship had a positive impact on URG students' STEM identity, attitudes, belonging, and self-efficacy. Furthermore, mentorship support functions indirectly predicted identity, attitudes, belonging, and self-efficacy among URG mentees who had women compared to men faculty mentors. CONCLUSIONS: Implications for how STEM faculty, regardless of their gender identity, can be effective mentors to URG students are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

14.
J Infect Dis ; 225(9): 1521-1532, 2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33319249

RESUMEN

BACKGROUND: Takeda's dengue vaccine is under evaluation in an ongoing phase 3 efficacy study; we present a 2-year update. METHODS: Children (20 099, 4-16 years old) were randomized to receive 2 doses of TAK-003 or placebo 3 months apart and are under surveillance to detect dengue by serotype-specific RT-PCR. RESULTS: Cumulative efficacy against dengue approximately 27 months since first dose was 72.7% (95% confidence interval [CI], 67.1%-77.3%), including 67.0% (95% CI, 53.6%-76.5%) in dengue-naive and 89.2% (95% CI, 82.4%-93.3%) against hospitalized dengue. In the second year, decline in efficacy was observed (56.2%; 95% CI, 42.3%-66.8%) with the largest decline in 4-5 year olds (24.5%; 95% CI, -34.2% to 57.5%); efficacy was 60.6% (95% CI, 43.8%-72.4%) in 6-11 year and 71.2% (95% CI, 41.0%-85.9%) in 12-16 year age groups. As TAK-003 efficacy varies by serotype, changes in serotype dominance partially contributed to efficacy differences in year-by-year analysis. No related serious adverse events occurred during the second year. CONCLUSIONS: TAK-003 demonstrated continued benefit independent of baseline serostatus in reducing dengue with some decline in efficacy during the second year. Three-year data will be important to see if efficacy stabilizes or declines further.Clinical Trials Registration. NCT02747927.Takeda's tetravalent dengue vaccine (TAK-003) continued to demonstrate benefit in reducing dengue independent of baseline serostatus up to 2 years after completing vaccination with some decline in efficacy during the second year in 4-16 year olds in dengue-endemic countries.


Asunto(s)
Vacunas contra el Dengue , Virus del Dengue , Dengue , Adolescente , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Niño , Preescolar , Virus del Dengue/genética , Método Doble Ciego , Humanos , Vacunación , Vacunas Atenuadas
15.
Clin Infect Dis ; 75(1): 107-117, 2022 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34606595

RESUMEN

BACKGROUND: Takeda's live attenuated tetravalent dengue vaccine candidate (TAK-003) is under evaluation in a long-term clinical trial across 8 dengue-endemic countries. Previously, we have reported its efficacy and safety in both seronegative and seropositive participants and that its performance varies by serotype, with some decline in efficacy from first to second year postvaccination. This exploratory analysis provides an update with cumulative and third-year data. METHODS: Healthy 4-16 year olds (n = 20099) were randomized 2:1 to receive TAK-003 or placebo (0, 3 month schedule). The protocol included baseline serostatus testing of all participants and detection of all symptomatic dengue throughout the trial with a serotype specific reverse transcriptase-polymerase chain reaction. RESULTS: Cumulative efficacy after 3 years was 62.0% (95% confidence interval, 56.6-66.7) against virologically confirmed dengue (VCD) and 83.6% (76.8-88.4) against hospitalized VCD. Efficacy was 54.3% (41.9-64.1) against VCD and 77.1% (58.6-87.3) against hospitalized VCD in baseline seronegatives, and 65.0% (58.9-70.1) against VCD and 86.0% (78.4-91.0) against hospitalized VCD in baseline seropositives. Efficacy against VCD during the third year declined to 44.7% (32.5-54.7), whereas efficacy against hospitalized VCD was sustained at 70.8% (49.6-83.0). Rates of serious adverse events were 2.9% in TAK-003 group and 3.5% in placebo group during the ongoing long-term follow-up (ie, second half of the 3 years following vaccination), but none were related. No important safety risks were identified. CONCLUSIONS: TAK-003 was efficacious against symptomatic dengue over 3 years. Efficacy declined over time but remained robust against hospitalized dengue. A booster dose evaluation is planned.


Asunto(s)
Vacunas contra el Dengue , Virus del Dengue , Dengue , Anticuerpos Antivirales , Humanos , Serogrupo , Resultado del Tratamiento , Vacunas Atenuadas/efectos adversos , Vacunas Combinadas
16.
N Engl J Med ; 381(21): 2009-2019, 2019 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-31693803

RESUMEN

BACKGROUND: Dengue, a mosquito-borne viral disease, was designated a World Health Organization top 10 threat to global health in 2019. METHODS: We present primary efficacy data from part 1 of an ongoing phase 3 randomized trial of a tetravalent dengue vaccine candidate (TAK-003) in regions of Asia and Latin America in which the disease is endemic. Healthy children and adolescents 4 to 16 years of age were randomly assigned in a 2:1 ratio (stratified according to age category and region) to receive two doses of vaccine or placebo 3 months apart. Participants presenting with febrile illness were tested for virologically confirmed dengue by serotype-specific reverse-transcriptase polymerase chain reaction. The primary end point was overall vaccine efficacy in preventing virologically confirmed dengue caused by any dengue virus serotype. RESULTS: Of the 20,071 participants who were given at least one dose of vaccine or placebo (safety population), 19,021 (94.8%) received both injections and were included in the per-protocol analysis. The overall vaccine efficacy in the safety population was 80.9% (95% confidence interval [CI], 75.2 to 85.3; 78 cases per 13,380 [0.5 per 100 person-years] in the vaccine group vs. 199 cases per 6687 [2.5 per 100 person-years] in the placebo group). In the per-protocol analyses, vaccine efficacy was 80.2% (95% CI, 73.3 to 85.3; 61 cases of virologically confirmed dengue in the vaccine group vs. 149 cases in the placebo group), with 95.4% efficacy against dengue leading to hospitalization (95% CI, 88.4 to 98.2; 5 hospitalizations in the vaccine group vs. 53 hospitalizations in the placebo group). Planned exploratory analyses involving the 27.7% of the per-protocol population that was seronegative at baseline showed vaccine efficacy of 74.9% (95% CI, 57.0 to 85.4; 20 cases of virologically confirmed dengue in the vaccine group vs. 39 cases in the placebo group). Efficacy trends varied according to serotype. The incidence of serious adverse events was similar in the vaccine group and placebo group (3.1% and 3.8%, respectively). CONCLUSIONS: TAK-003 was efficacious against symptomatic dengue in countries in which the disease is endemic. (Funded by Takeda Vaccines; TIDES ClinicalTrials.gov number, NCT02747927.).


Asunto(s)
Vacunas contra el Dengue/inmunología , Virus del Dengue/inmunología , Dengue/prevención & control , Enfermedades Endémicas/prevención & control , Adolescente , Américas/epidemiología , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Asia/epidemiología , Niño , Preescolar , Dengue/epidemiología , Dengue/inmunología , Vacunas contra el Dengue/efectos adversos , Virus del Dengue/aislamiento & purificación , Método Doble Ciego , Femenino , Humanos , Incidencia , Masculino , Serogrupo , Resultado del Tratamiento
17.
Ecol Appl ; 32(3): e2526, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34994033

RESUMEN

Forest biodiversity conservation and species distribution modeling greatly benefit from broad-scale forest maps depicting tree species or forest types rather than just presence and absence of forest, or coarse classifications. Ideally, such maps would stem from satellite image classification based on abundant field data for both model training and accuracy assessments, but such field data do not exist in many parts of the globe. However, different forest types and tree species differ in their vegetation phenology, offering an opportunity to map and characterize forests based on the seasonal dynamic of vegetation indices and auxiliary data. Our goal was to map and characterize forests based on both land surface phenology and climate patterns, defined here as forest phenoclusters. We applied our methodology in Argentina (2.8 million km2 ), which has a wide variety of forests, from rainforests to cold-temperate forests. We calculated phenology measures after fitting a harmonic curve of the enhanced vegetation index (EVI) time series derived from 30-m Sentinel 2 and Landsat 8 data from 2018-2019. For climate, we calculated land surface temperature (LST) from Band 10 of the thermal infrared sensor (TIRS) of Landsat 8, and precipitation from Worldclim (BIO12). We performed stratified X-means cluster classifications followed by hierarchical clustering. The resulting clusters separated well into 54 forest phenoclusters with unique combinations of vegetation phenology and climate characteristics. The EVI 90th percentile was more important than our climate and other phenology measures in providing separability among different forest phenoclusters. Our results highlight the potential of combining remotely sensed phenology measures and climate data to improve broad-scale forest mapping for different management and conservation goals, capturing functional rather than structural or compositional characteristics between and within tree species. Our approach results in classifications that go beyond simple forest-nonforest in areas where the lack of detailed ecological field data precludes tree species-level classifications, yet conservation needs are high. Our map of forest phenoclusters is a valuable tool for the assessment of natural resources, and the management of the environment at scales relevant for conservation actions.


Asunto(s)
Bosques , Árboles , Argentina , Biodiversidad , Clima
18.
J Environ Sci Health B ; 57(12): 970-979, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36511900

RESUMEN

Pesticide usage has contributed to increasing food production; it has also caused them to be found in ecosystems inducing adverse effects on biota. Fish are the most abundant and diverse vertebrates in the world and are of great importance both economically and ecologically. Some fishes are indicators of the environmental quality of aquatic ecosystems and provide insight as to how pollutants might influence public health. The tilapias species can be considered biomonitors because they present little displacement representing the contamination level of a site. This study aimed at three goals: (1) to determine the concentration of 20 pesticides in tilapia muscle in the Ayuquila-Armería basin, (2) to describe the spatiotemporal variation of analytes and (3) to evaluate the risk of consuming contaminated fish. The presence of 11 pesticides was determined. Ametrine, glyphosate and malathion concentrations showed significant differences by season. The risk assessment showed that the consumption of tilapia muscle from the Ayuquila-Armería basin does not represent a risk for the population. Diazinon concentrations were relatively low compared to the other pesticides concentrations, but its toxic characteristics were the ones that most negatively influenced the risk assessment. The results obtained are relevant from the social and economic points of view.


Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Animales , Humanos , Plaguicidas/toxicidad , Plaguicidas/análisis , Ecosistema , Ríos , México , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Peces/fisiología , Medición de Riesgo
19.
Environ Monit Assess ; 194(7): 474, 2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35657507

RESUMEN

The pesticides used have contributed to increasing food production; it has also caused them to be found in most ecosystems and have negative effects on biota. The neotropical otter (Lontra longicaudis) is vulnerable to pesticide accumulation and is characterized by being elusive, so it is necessary to address the use of indirect techniques that evaluate its populations' state in an efficient, logistically simple, and non-invasive way. This study aimed to determine the concentration of 20 pesticides in neotropical otter feces in the Ayuquila-Armería basin and to describe the spatiotemporal variation of these pesticides. The presence of 11 pesticides was determined. Imazalil, picloram, and malathion the pesticides with the highest concentrations; emamectin, λ-cyhalothrin, methomyl, and picloram were present in all samples. Emamectin was the only pesticide that presented significant differences concerning the temporality of the samplings, presenting higher concentrations in the wet season. Molinate concentrations showed significant differences concerning the location of the sampling sections in the basin; the lower part of the basin presented higher concentrations. The distribution of the populations of L. longicaudis in the Ayuquila-Armería basin does not respond to the degree of contamination by pesticides in surface waters or to the proximity to agricultural activities, and this in places with evident chemical and organic contamination and human presence. The use of otter feces for pesticide monitoring is an accepted non-invasive method to assess the degree of exposure and can be used to determine sites with pollution problems.


Asunto(s)
Nutrias , Plaguicidas , Contaminantes Químicos del Agua , Animales , Ecosistema , Monitoreo del Ambiente , Heces/química , Humanos , México , Plaguicidas/análisis , Picloram/análisis , Contaminantes Químicos del Agua/análisis
20.
Lancet ; 395(10234): 1434-1443, 2020 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-32197107

RESUMEN

BACKGROUND: An unmet clinical need remains for an effective tetravalent dengue vaccine suitable for all age groups, regardless of serostatus. We assessed the immunogenicity and safety of three different dose schedules of a tetravalent dengue vaccine (TAK-003) over a 48-month period in children living in dengue-endemic countries. METHODS: We did a large, phase 2, double-blind, placebo-controlled trial at three sites in the Dominican Republic, Panama, and the Philippines. Healthy participants aged 2-17 years were randomly assigned 1:2:5:1 using an interactive web response system with stratification by age to receive either a two-dose primary series (days 1 and 91), one primary dose (day 1), one primary dose plus booster (days 1 and 365), or placebo. Participants and relevant study personnel were masked to the random assignment until completion of the study at month 48. To maintain masking, TAK-003 recipients were administered placebo doses when appropriate. The primary objective was assessment of neutralising geometric mean titres for each serotype to month 48 assessed in the per-protocol immunogenicity subset. Secondary safety endpoints included proportions of participants with serious adverse events and symptomatic virologically confirmed dengue. This study is registered with ClinicalTrials.gov, NCT02302066. FINDINGS: Between Dec 5, 2014, and Feb 13, 2015, 1800 children were randomly assigned to the following groups: two-dose primary series (n=201), one primary dose (n=398), one primary dose plus 1-year booster (n=1002), and placebo (n=199). Of them, 1479 (82%) participants completed the 48-month study. Immunogenicity endpoints were assessed in 562 participants enrolled in the immunogenicity subset, of whom 509 were included in the per-protocol subset. At month 48, antibody titres remained elevated in all TAK-003 groups compared with placebo, irrespective of baseline serostatus. At month 48, geometric mean titres were 378 (95% CI 226-632) in two-dose, 421 (285-622) in one-dose, 719 (538-960) in one-dose plus 1-year booster, and 100 (50-201) in placebo recipients against DENV 1; 1052 (732-1511), 1319 (970-1794), 1200 (927-1553), and 208 (99-437) against DENV 2; 183 (113-298), 201 (135-298), 288 (211-392), and 71 (37-139) against DENV 3; and 152 (97-239), 164 (114-236), 219 (165-290), and 46 (26-82) against DENV 4; and tetravalent seropositivity rate was 89% (79-96), 86% (80-92), 97% (93-99), and 60% (47-72), respectively. Virologically confirmed dengue was recorded in 37 (2%) TAK-003 and 13 (7%) placebo participants, with a relative risk of 0·35 (0·19-0·65). No vaccine-related serious adverse events or severe dengue virus disease were reported. INTERPRETATION: TAK-003 elicited antibody responses against all four serotypes, which persisted to 48 months post-vaccination, regardless of baseline serostatus. No important safety risks were identified. We observed a long-term reduction in risk of symptomatic dengue virus disease in vaccinees. Results from this study provide a long-term safety database and support assessment of the vaccine in the ongoing phase 3 efficacy study. FUNDING: Takeda Vaccines.


Asunto(s)
Vacunas contra el Dengue/efectos adversos , Virus del Dengue/inmunología , Dengue/prevención & control , Inmunogenicidad Vacunal/inmunología , Adolescente , Niño , Preescolar , Dengue/inmunología , Dengue/virología , Vacunas contra el Dengue/administración & dosificación , Virus del Dengue/genética , República Dominicana/epidemiología , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Inmunización Secundaria/métodos , Masculino , Panamá/epidemiología , Filipinas/epidemiología , Placebos/administración & dosificación , Seguridad , Serogrupo , Vacunación/métodos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA