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1.
Trends Genet ; 39(7): 531-544, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36907721

RESUMO

Insects are crucial for ecosystem health but climate change and pesticide use are driving massive insect decline. To mitigate this loss, we need new and effective monitoring techniques. Over the past decade there has been a shift to DNA-based techniques. We describe key emerging techniques for sample collection. We suggest that the selection of tools should be broadened, and that DNA-based insect monitoring data need to be integrated more rapidly into policymaking. We argue that there are four key areas for advancement, including the generation of more complete DNA barcode databases to interpret molecular data, standardisation of molecular methods, scaling up of monitoring efforts, and integrating molecular tools with other technologies that allow continuous, passive monitoring based on images and/or laser imaging, detection, and ranging (LIDAR).


Assuntos
Biodiversidade , Ecossistema , Animais , Código de Barras de DNA Taxonômico/métodos , DNA/genética , Insetos/genética
2.
Nature ; 580(7802): 263-268, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32269334

RESUMO

In cells, organs and whole organisms, nutrient sensing is key to maintaining homeostasis and adapting to a fluctuating environment1. In many animals, nutrient sensors are found within the enteroendocrine cells of the digestive system; however, less is known about nutrient sensing in their cellular siblings, the absorptive enterocytes1. Here we use a genetic screen in Drosophila melanogaster to identify Hodor, an ionotropic receptor in enterocytes that sustains larval development, particularly in nutrient-scarce conditions. Experiments in Xenopus oocytes and flies indicate that Hodor is a pH-sensitive, zinc-gated chloride channel that mediates a previously unrecognized dietary preference for zinc. Hodor controls systemic growth from a subset of enterocytes-interstitial cells-by promoting food intake and insulin/IGF signalling. Although Hodor sustains gut luminal acidity and restrains microbial loads, its effect on systemic growth results from the modulation of Tor signalling and lysosomal homeostasis within interstitial cells. Hodor-like genes are insect-specific, and may represent targets for the control of disease vectors. Indeed, CRISPR-Cas9 genome editing revealed that the single hodor orthologue in Anopheles gambiae is an essential gene. Our findings highlight the need to consider the instructive contributions of metals-and, more generally, micronutrients-to energy homeostasis.


Assuntos
Canais de Cloreto/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Ingestão de Alimentos/fisiologia , Intestinos/fisiologia , Zinco/metabolismo , Animais , Drosophila melanogaster/genética , Enterócitos/metabolismo , Feminino , Preferências Alimentares , Homeostase , Insetos Vetores , Insulina/metabolismo , Ativação do Canal Iônico , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Lisossomos/metabolismo , Masculino , Oócitos/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais , Xenopus
3.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35042801

RESUMO

Life on Earth has evolved from initial simplicity to the astounding complexity we experience today. Bacteria and archaea have largely excelled in metabolic diversification, but eukaryotes additionally display abundant morphological innovation. How have these innovations come about and what constraints are there on the origins of novelty and the continuing maintenance of biodiversity on Earth? The history of life and the code for the working parts of cells and systems are written in the genome. The Earth BioGenome Project has proposed that the genomes of all extant, named eukaryotes-about 2 million species-should be sequenced to high quality to produce a digital library of life on Earth, beginning with strategic phylogenetic, ecological, and high-impact priorities. Here we discuss why we should sequence all eukaryotic species, not just a representative few scattered across the many branches of the tree of life. We suggest that many questions of evolutionary and ecological significance will only be addressable when whole-genome data representing divergences at all of the branchings in the tree of life or all species in natural ecosystems are available. We envisage that a genomic tree of life will foster understanding of the ongoing processes of speciation, adaptation, and organismal dependencies within entire ecosystems. These explorations will resolve long-standing problems in phylogenetics, evolution, ecology, conservation, agriculture, bioindustry, and medicine.


Assuntos
Sequência de Bases/genética , Eucariotos/genética , Genômica/ética , Animais , Biodiversidade , Evolução Biológica , Ecologia , Ecossistema , Genoma , Genômica/métodos , Humanos , Filogenia
4.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35042802

RESUMO

A global international initiative, such as the Earth BioGenome Project (EBP), requires both agreement and coordination on standards to ensure that the collective effort generates rapid progress toward its goals. To this end, the EBP initiated five technical standards committees comprising volunteer members from the global genomics scientific community: Sample Collection and Processing, Sequencing and Assembly, Annotation, Analysis, and IT and Informatics. The current versions of the resulting standards documents are available on the EBP website, with the recognition that opportunities, technologies, and challenges may improve or change in the future, requiring flexibility for the EBP to meet its goals. Here, we describe some highlights from the proposed standards, and areas where additional challenges will need to be met.


Assuntos
Sequência de Bases/genética , Eucariotos/genética , Genômica/normas , Animais , Biodiversidade , Genômica/métodos , Humanos , Padrões de Referência , Valores de Referência , Análise de Sequência de DNA/métodos , Análise de Sequência de DNA/normas
5.
Annu Rev Entomol ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353093

RESUMO

Most insects encountered in the field are initially entomological dark matter in that they cannot be identified to species while alive. This explains the enduring quest for efficient ways to identify collected specimens. Morphological tools came first but are now routinely replaced or complemented with DNA barcodes. Initially too expensive for widespread use, these barcodes have since evolved into powerful tools for specimen identification and sorting, given that the evolution of sequencing approaches has dramatically reduced the cost of barcodes, thus enabling decentralized deployment across the planet. In this article, we review how DNA barcodes have become a key tool for accelerating biodiversity discovery and analyzing insect communities through both megabarcoding and metabarcoding in an era of insect decline. We predict that DNA barcodes will be particularly important for assembling image training sets for deep learning algorithms, global biodiversity genomics, and functional analysis of insect communities.

6.
PLoS Pathog ; 18(3): e1010346, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35255094

RESUMO

Early diverging lineages such as trypanosomes can provide clues to the evolution of sexual reproduction in eukaryotes. In Trypanosoma brucei, the pathogen that causes Human African Trypanosomiasis, sexual reproduction occurs in the salivary glands of the insect host, but analysis of the molecular signatures that define these sexual forms is complicated because they mingle with more numerous, mitotically-dividing developmental stages. We used single-cell RNA-sequencing (scRNAseq) to profile 388 individual trypanosomes from midgut, proventriculus, and salivary glands of infected tsetse flies allowing us to identify tissue-specific cell types. Further investigation of salivary gland parasite transcriptomes revealed fine-scale changes in gene expression over a developmental progression from putative sexual forms through metacyclics expressing variant surface glycoprotein genes. The cluster of cells potentially containing sexual forms was characterized by high level transcription of the gamete fusion protein HAP2, together with an array of surface proteins and several genes of unknown function. We linked these expression patterns to distinct morphological forms using immunofluorescence assays and reporter gene expression to demonstrate that the kinetoplastid-conserved gene Tb927.10.12080 is exclusively expressed at high levels by meiotic intermediates and gametes. Further experiments are required to establish whether this protein, currently of unknown function, plays a role in gamete formation and/or fusion.


Assuntos
Trypanosoma brucei brucei , Trypanosoma , Tripanossomíase Africana , Moscas Tsé-Tsé , Animais , Transcriptoma , Trypanosoma/genética , Trypanosoma brucei brucei/genética , Tripanossomíase Africana/parasitologia , Moscas Tsé-Tsé/genética , Moscas Tsé-Tsé/parasitologia
7.
Mol Ecol ; : e17542, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39374937

RESUMO

A major insecticide resistance mechanism in insect pests is knock-down resistance (kdr) caused by mutations in the voltage-gated sodium channel (Vgsc) gene. Despite being common in most malaria Anopheles vector species, kdr mutations have never been observed in Anopheles funestus, the principal malaria vector in Eastern and Southern Africa, with resistance mainly being conferred by detoxification enzymes. In a parallel study, we monitored 10 populations of An. funestus in Tanzania for insecticide resistance unexpectedly identified resistance to a banned insecticide, DDT, in the Morogoro region. Through whole-genome sequencing of 333 An. funestus samples from these populations, we found eight novel amino acid substitutions in the Vgsc gene, including the kdr variant, L976F (equivalent to L995F in An. gambiae), in tight linkage disequilibrium with another (P1842S). The mutants were found only at high frequency in one region and were accompanied by weak signatures of a selective sweep, with a significant decline between 2017 and 2023. Notably, kdr L976F was strongly associated with survivorship to exposure to DDT insecticide, while no clear association was noted with a pyrethroid insecticide (deltamethrin). The WHO prequalifies no DDT products for vector control, and the chemical is banned in Tanzania. Widespread DDT contamination and a legacy of extensive countrywide stockpiles may have selected for this mutation. Continued monitoring is necessary to understand the origin of kdr in An. funestus, and the threat posed to insecticide-based vector control in Africa.

8.
Am J Perinatol ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39406374

RESUMO

BACKGROUND: Hypoxemia and respiratory compromise occur in very low birthweight (VLBW, <1500 grams) infants and may be associated with shunting across a patent ductus arteriosus (PDA). The impact of pharmacologic PDA treatment on acute hypoxemia and respiratory metrics is unclear. OBJECTIVE: To determine whether pharmacologic PDA treatment is associated with acute improvement in hypoxemia and respiratory metrics in VLBW infants. STUDY DESIGN: At a single center (2012-2022), all VLBW infants with echocardiographic evidence of a PDA and without exclusions were classified as having received or not received pharmacologic PDA treatment (PDA-T, PDA-NT). Mean daily FiO2 and Respiratory Acuity Score (RAS, PMID 30374050) were compared at baseline (day 0) and 3 days after treatment start. For PDA-T infants with archived 0.5Hz (every-2-second) SpO2 data, mean daily SpO2 and the percentage of time with severe hypoxemia (SpO2 <80%) were compared before and after treatment. Severe hypoxemia was further analyzed after stratification by clinical variables (sex, medication, gestational age, postnatal age). RESULTS: We analyzed 125 VLBW infants with a PDA, of whom 66 received pharmacologic PDA treatment. We analyzed a subgroup of 43 PDA-T infants with every-2-second SpO2 data available. PDA-T infants had higher baseline FiO2 and RAS and lower SpO2 than PDA-NT infants (p<0.05). Compared to baseline, RAS decreased from median 258 (IQR 171, 348) to 254 (IQR 174, 419) three days after the start of treatment (p=0.012), but median FiO2 increased from 37% (IQR 28, 46) to 40% (IQR 29, 52) (p=0.008). SpO2 and the percent time with severe hypoxemia were unchanged. CONCLUSIONS: In this 10-year retrospective single-center analysis, pharmacologic PDA treatment in VLBW infants was not associated with a major improvement in acute measures of oxygenation or level of respiratory support.

9.
Nat Methods ; 17(6): 615-620, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32366989

RESUMO

Methods to deconvolve single-cell RNA-sequencing (scRNA-seq) data are necessary for samples containing a mixture of genotypes, whether they are natural or experimentally combined. Multiplexing across donors is a popular experimental design that can avoid batch effects, reduce costs and improve doublet detection. By using variants detected in scRNA-seq reads, it is possible to assign cells to their donor of origin and identify cross-genotype doublets that may have highly similar transcriptional profiles, precluding detection by transcriptional profile. More subtle cross-genotype variant contamination can be used to estimate the amount of ambient RNA. Ambient RNA is caused by cell lysis before droplet partitioning and is an important confounder of scRNA-seq analysis. Here we develop souporcell, a method to cluster cells using the genetic variants detected within the scRNA-seq reads. We show that it achieves high accuracy on genotype clustering, doublet detection and ambient RNA estimation, as demonstrated across a range of challenging scenarios.


Assuntos
RNA-Seq/métodos , RNA/genética , Análise de Célula Única/métodos , Algoritmos , Sequência de Bases , Linhagem Celular , Análise por Conglomerados , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Sensibilidade e Especificidade , Software
10.
Genome Res ; 29(8): 1250-1261, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31345938

RESUMO

Polymorphisms in genetic copy number can influence gene expression, coding sequence, and zygosity, making them powerful actors in the evolutionary process. Copy number variants (CNVs) are however understudied, being more difficult to detect than single-nucleotide polymorphisms. We take advantage of the intense selective pressures on the major malaria vector Anopheles gambiae, caused by the widespread use of insecticides for malaria control, to investigate the role of CNVs in the evolution of insecticide resistance. Using the whole-genome sequencing data from 1142 samples in the An. gambiae 1000 genomes project, we identified 250 gene-containing CNVs, encompassing a total of 267 genes of which 28 were in gene families linked to metabolic insecticide resistance, representing significant enrichment of these families. The five major gene clusters for metabolic resistance all contained CNVs, with 44 different CNVs being found across these clusters and multiple CNVs frequently covering the same genes. These 44 CNVs are widespread (45% of individuals carry at least one of them) and have been spreading through positive selection, indicated by their high local frequencies and extended haplotype homozygosity. Our results demonstrate the importance of CNVs in the response to selection, highlighting the urgent need to identify the contribution of each CNV to insecticide resistance and to track their spread as the use of insecticides in malaria endemic countries intensifies and as the operational deployment of next-generation bed nets targeting metabolic resistance gathers pace. Our detailed descriptions of CNVs found across the species range provide the tools to do so.


Assuntos
Anopheles/genética , Sistema Enzimático do Citocromo P-450/genética , Variações do Número de Cópias de DNA , Genoma de Inseto , Resistência a Inseticidas/genética , Mosquitos Vetores/genética , Animais , Anopheles/parasitologia , Evolução Biológica , Mapeamento Cromossômico , Sistema Enzimático do Citocromo P-450/metabolismo , Dosagem de Genes , Loci Gênicos , Haplótipos , Homozigoto , Humanos , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Inseticidas , Malária/prevenção & controle , Malária/transmissão , Mosquitos Vetores/parasitologia , Família Multigênica , Piretrinas , Seleção Genética , Sequenciamento Completo do Genoma
11.
PLoS Pathog ; 15(11): e1008063, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31697788

RESUMO

Mating causes dramatic changes in female physiology, behaviour, and immunity in many insects, inducing oogenesis, oviposition, and refractoriness to further mating. Females from the Anopheles gambiae species complex typically mate only once in their lifetime during which they receive sperm and seminal fluid proteins as well as a mating plug that contains the steroid hormone 20-hydroxyecdysone. This hormone, which is also induced by blood-feeding, plays a major role in activating vitellogenesis for egg production. Here we show that female Anopheles coluzzii susceptibility to Plasmodium falciparum infection is significantly higher in mated females compared to virgins. We also find that mating status has a major impact on the midgut transcriptome, detectable only under sugar-fed conditions: once females have blood-fed, the transcriptional changes that are induced by mating are likely masked by the widespread effects of blood-feeding on gene expression. To determine whether increased susceptibility to parasites could be driven by the additional 20E that mated females receive from males, we mimicked mating by injecting virgin females with 20E, finding that these females are significantly more susceptible to human malaria parasites than virgin females injected with the control 20E carrier. Further RNAseq was carried out to examine whether the genes that change upon 20E injection in the midgut are similar to those that change upon mating. We find that 79 midgut-expressed genes are regulated in common by both mating and 20E, and 96% (n = 76) of these are regulated in the same direction (up vs down in 20E/mated). Together, these findings show that male Anopheles mosquitoes induce changes in the female midgut that can affect female susceptibility to P. falciparum. This implies that in nature, males might contribute to malaria transmission in previously unappreciated ways, and that vector control strategies that target males may have additional benefits towards reducing transmission.


Assuntos
Anopheles/fisiologia , Sistema Digestório/fisiopatologia , Malária/transmissão , Mosquitos Vetores/patogenicidade , Comportamento Sexual Animal/fisiologia , Transcriptoma , Animais , Sistema Digestório/metabolismo , Sistema Digestório/parasitologia , Suscetibilidade a Doenças , Feminino , Humanos , Hormônios de Inseto/metabolismo , Malária/parasitologia , Masculino , Oviposição , Reprodução
12.
Malar J ; 20(1): 234, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34034756

RESUMO

BACKGROUND: The emergence of insecticide resistance is a major threat to malaria control programmes in Africa, with many different factors contributing to insecticide resistance in its vectors, Anopheles mosquitoes. CYP6M2 has previously been recognized as an important candidate in cytochrome P450-mediated detoxification in Anopheles. As it has been implicated in resistance against pyrethroids, organochlorines and carbamates, its broad metabolic activity makes it a potential agent in insecticide cross-resistance. Currently, allelic variation within the Cyp6m2 gene remains unknown. METHODS: Here, Illumina whole-genome sequence data from Phase 2 of the Anopheles gambiae 1000 Genomes Project (Ag1000G) was used to examine genetic variation in the Cyp6m2 gene across 16 populations in 13 countries comprising Anopheles gambiae and Anopheles coluzzii mosquitoes. To identify whether these alleles show evidence of selection either through potentially modified enzymatic function or by being linked to variants that change the transcriptional profile of the gene, hierarchical clustering of haplotypes, linkage disequilibrium, median joining networks and extended haplotype homozygosity analyses were performed. RESULTS: Fifteen missense biallelic substitutions at high frequency (defined as > 5% frequency in one or more populations) are found, which fall into five distinct haplotype groups that carry the main high frequency variants: A13T, D65A, E328Q, Y347F, I359V and A468S. Despite consistent reports of Cyp6m2 upregulation and metabolic activity in insecticide resistant Anophelines, no evidence of directional selection is found occurring on these variants or on the haplotype clusters in which they are found. CONCLUSION: These results imply that emerging resistance associated with Cyp6m2 is potentially driven by distant regulatory loci such as transcriptional factors rather than by its missense variants, or that other genes are playing a more significant role in conferring metabolic resistance.


Assuntos
Anopheles/genética , Variação Genética , Resistência a Inseticidas/genética , Mosquitos Vetores/genética , Animais , Anopheles/efeitos dos fármacos , Proteínas de Insetos , Mosquitos Vetores/efeitos dos fármacos , Especificidade da Espécie
13.
Arterioscler Thromb Vasc Biol ; 40(11): 2605-2618, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32998516

RESUMO

OBJECTIVE: Pulmonary arterial hypertension is a disease of proliferative vascular occlusion that is strongly linked to mutations in BMPR2-the gene encoding the BMPR-II (BMP [bone morphogenetic protein] type II receptor). The endothelial-selective BMPR-II ligand, BMP9, reverses disease in animal models of pulmonary arterial hypertension and suppresses the proliferation of healthy endothelial cells. However, the impact of BMPR2 loss on the antiproliferative actions of BMP9 has yet to be assessed. Approach and Results: BMP9 suppressed proliferation in blood outgrowth endothelial cells from healthy control subjects but increased proliferation in blood outgrowth endothelial cells from pulmonary arterial hypertension patients with BMPR2 mutations. This shift from growth suppression to enhanced proliferation was recapitulated in control human pulmonary artery endothelial cells following siRNA-mediated BMPR2 silencing, as well as in mouse pulmonary endothelial cells isolated from endothelial-conditional Bmpr2 knockout mice (Bmpr2EC-/-). BMP9-induced proliferation was not attributable to altered metabolic activity or elevated TGFß (transforming growth factor beta) signaling but was linked to the prolonged induction of the canonical BMP target ID1 in the context of BMPR2 loss. In vivo, daily BMP9 administration to neonatal mice impaired both retinal and lung vascular patterning in control mice (Bmpr2EC+/+) but had no measurable effect on mice bearing a heterozygous endothelial Bmpr2 deletion (Bmpr2EC+/-) and caused excessive angiogenesis in both vascular beds for Bmpr2EC-/- mice. CONCLUSIONS: BMPR2 loss reverses the endothelial response to BMP9, causing enhanced proliferation. This finding has potential implications for the proposed translation of BMP9 as a treatment for pulmonary arterial hypertension and suggests the need for focused patient selection in clinical trials.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo II/deficiência , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Fator 2 de Diferenciação de Crescimento/farmacologia , Hipertensão Arterial Pulmonar/tratamento farmacológico , Adulto , Idoso , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Estudos de Casos e Controles , Células Cultivadas , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Fator 2 de Diferenciação de Crescimento/toxicidade , Humanos , Proteínas Inibidoras de Diferenciação/genética , Proteínas Inibidoras de Diferenciação/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/patologia , Transdução de Sinais , Adulto Jovem
14.
Fetal Diagn Ther ; 48(8): 603-610, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34518445

RESUMO

INTRODUCTION: Prenatal closure of open spina bifida via open fetal surgery improves neurologic outcomes for infants in selected pregnancies. Fetoscopic techniques that are minimally invasive to the uterus aim to provide equivalent fetal benefits while minimizing maternal morbidities, but the optimal technique is undetermined. We describe the development, evolution, and feasibility of the laparotomy-assisted 2-port fetoscopic technique for prenatal closure of fetal spina bifida in a newly established program. METHODS: We conducted a retrospective cohort study of women consented for laparotomy-assisted fetoscopic closure of isolated fetal spina bifida. Inclusion and exclusion criteria followed the Management of Myelomeningocele Study (MOMS). Team preparation involved observation at the originating center, protocol development, ancillary staff training, and surgical rehearsal using patient-matched models through simulation prior to program implementation. The primary outcome was the ability to complete the repair fetoscopically. Secondary maternal and fetal outcomes to assess performance of the technique were collected prospectively. RESULTS: Of 57 women screened, 19 (33%) consented for laparotomy-assisted 2-port fetoscopy between February 2017 and December 2019. Fetoscopic closure was completed in 84% (16/19) cases. Over time, the technique was modified from a single- to a multilayer closure. In utero hindbrain herniation improved in 86% (12/14) of undelivered patients at 6 weeks postoperatively. Spontaneous rupture of membranes occurred in 31% (5/16) of fetoscopic cases. For completed cases, median gestational age at birth was 37 (range 27-39.6) weeks and 50% (8/16) of women delivered at term. Vaginal birth was achieved in 56% (9/16) of patients. One newborn had a cerebrospinal fluid leak that required postnatal surgical repair. CONCLUSION: Implementation of a laparotomy-assisted 2-port fetoscopic spina bifida closure program through rigorous preparation and multispecialty team training may accelerate the learning curve and demonstrates favorable obstetric and perinatal outcomes.


Assuntos
Meningomielocele , Disrafismo Espinal , Feminino , Fetoscopia/efeitos adversos , Humanos , Lactente , Recém-Nascido , Laparotomia , Meningomielocele/cirurgia , Gravidez , Estudos Retrospectivos , Disrafismo Espinal/diagnóstico por imagem , Disrafismo Espinal/cirurgia
15.
Artigo em Inglês | MEDLINE | ID: mdl-33139275

RESUMO

Resistance to artemisinin-based combination therapy (ACT) in the Plasmodium falciparum parasite is threatening to reverse recent gains in reducing global deaths from malaria. While resistance manifests as delayed parasite clearance in patients, the phenotype can only spread geographically via the sexual stages and mosquito transmission. In addition to their asexual killing properties, artemisinin and its derivatives sterilize sexual male gametocytes. Whether resistant parasites overcome this sterilizing effect has not, however, been fully tested. Here, we analyzed P. falciparum clinical isolates from the Greater Mekong Subregion, each demonstrating delayed clinical clearance and known resistance-associated polymorphisms in the Kelch13 (PfK13var) gene. As well as demonstrating reduced asexual sensitivity to drug, certain PfK13var isolates demonstrated a marked reduction in sensitivity to artemisinin in an in vitro male gamete formation assay. Importantly, this same reduction in sensitivity was observed when the most resistant isolate was tested directly in mosquito feeds. These results indicate that, under artemisinin drug pressure, while sensitive parasites are blocked, resistant parasites continue transmission. This selective advantage for resistance transmission could favor acquisition of additional host-specificity or polymorphisms affecting partner drug sensitivity in mixed infections. Favored resistance transmission under ACT coverage could have profound implications for the spread of multidrug-resistant malaria beyond Southeast Asia.


Assuntos
Antimaláricos , Artemisininas , Culicidae , Malária Falciparum , Parasitos , Animais , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Sudeste Asiático , Resistência a Medicamentos/genética , Humanos , Malária Falciparum/tratamento farmacológico , Masculino , Plasmodium falciparum/genética
16.
Genome Res ; 27(9): 1536-1548, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28747381

RESUMO

Understanding how phenotypic differences between males and females arise from the sex-biased expression of nearly identical genomes can reveal important insights into the biology and evolution of a species. Among Anopheles mosquito species, these phenotypic differences include vectorial capacity, as it is only females that blood feed and thus transmit human malaria. Here, we use RNA-seq data from multiple tissues of four vector species spanning the Anopheles phylogeny to explore the genomic and evolutionary properties of sex-biased genes. We find that, in these mosquitoes, in contrast to what has been found in many other organisms, female-biased genes are more rapidly evolving in sequence, expression, and genic turnover than male-biased genes. Our results suggest that this atypical pattern may be due to the combination of sex-specific life history challenges encountered by females, such as blood feeding. Furthermore, female propensity to mate only once in nature in male swarms likely diminishes sexual selection of post-reproductive traits related to sperm competition among males. We also develop a comparative framework to systematically explore tissue- and sex-specific splicing to document its conservation throughout the genus and identify a set of candidate genes for future functional analyses of sex-specific isoform usage. Finally, our data reveal that the deficit of male-biased genes on the X Chromosomes in Anopheles is a conserved feature in this genus and can be directly attributed to chromosome-wide transcriptional regulation that de-masculinizes the X in male reproductive tissues.


Assuntos
Anopheles/genética , Evolução Molecular , Genes Ligados ao Cromossomo X/genética , Proteínas de Insetos/genética , Malária/genética , Animais , Anopheles/patogenicidade , Feminino , Regulação da Expressão Gênica/genética , Especiação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Malária/parasitologia , Malária/transmissão , Masculino , Especificidade de Órgãos/genética , Filogenia , Caracteres Sexuais , Cromossomo X/genética
17.
Osteoporos Int ; 31(9): 1787-1799, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32377805

RESUMO

Our study investigates 25-hydroxyvitamin D levels and fracture risk using population-level data. 25-Hydroxyvitamin D values < 12, 12-19, and > 50 ng/mL were not associated with increased risk of fractures overall compared with values 20-50 ng/mL. Severely low levels may be associated with increased risk of osteoporotic fracture, particularly of the wrist. INTRODUCTION: Studies of the relationship between serum 25-hydroxyvitamin D (25(OH)D) levels and fracture risk have been inconsistent. We hypothesized that high 25(OH)D concentrations (> 50 ng/mL) would be associated with increased risk of fracture. METHODS: We identified all adult patients living in Olmsted County, Minnesota, between January 1, 2005 and December 31, 2011, who had at least one 25(OH)D measurement. Fracture outcomes were retrieved starting 30 days after 25(OH)D measurement and until patients' final clinical visit as an Olmsted County resident, December 31, 2014, or death. Data were analyzed using Cox proportional hazard regression. RESULTS: Of 11,002 individuals with a 25(OH)D measurement, 5.8% had a 25(OH)D value ˂ 12 ng/mL, and 5.1% had a value > 50 ng/mL. Compared with subjects with 25(OH)D values 20-50 ng/mL (reference group), values < 12, 12-19, and > 50 ng/mL displayed no association with overall fracture risk. After adjusting for a prior diagnosis of osteoporosis/osteopenia, only individuals with values ˂ 12 ng/mL had increased risk of any osteoporotic fracture (aHR = 1.41; 95% CI 1.05-1.89) and wrist fracture (aHR = 2.11; 95% CI 1.27-3.48) compared with the reference group. Compared with the reference group, values ˂ 12 ng/mL were associated with increased risk of any fracture (aHR = 1.35; 95% CI 1.01-1.80), osteoporotic fracture (aHR = 2.18; 95% CI 1.44-3.31), and wrist fracture (aHR = 2.39; 95% CI 1.19-4.81) in subjects without a prior diagnosis of osteoporosis/osteopenia, but not in those with a prior diagnosis of osteoporosis/osteopenia. CONCLUSION: Severely low 25(OH)D levels may be associated with increased risk of osteoporotic fracture, particularly of the wrist, but 25(OH)D values > 50 ng/mL were not associated with increased fracture risk.


Assuntos
Deficiência de Vitamina D , Vitamina D , Adulto , Estudos de Coortes , Humanos , Minnesota/epidemiologia , Estudos Retrospectivos , Vitamina D/análogos & derivados , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia
18.
Gynecol Oncol ; 152(1): 151-156, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30414740

RESUMO

OBJECTIVE: Pelvic exenteration (PE) is an extensive surgery associated with high rates of postoperative morbidity and mortality. The absence of well-defined preoperative selection criteria to identify patients eligible for PE prompted the assessment of pre-operative predictors of 30-day major surgical complications. METHODS: Demographics and surgical characteristics of patients undergoing PE for gynecologic cancer in a single institution between 01/2004-12/2016 were reviewed. Postoperative complications within 30 days following surgery were graded using the Accordion grading system. Logistic regression was used to analyze potential risk factors for severe postoperative complications. RESULTS: A total of 138 patients were included in the cohort. Forty-five patients underwent total PE, 52 anterior PE, and 41 posterior PE. Among the 137 patients with follow-up, a severe postoperative complication was experienced by 37 patients (27.0%) and 3 patients (2.2%) experienced death within 90 days. The most frequent grade 3 complications were complications of urinary reconstruction (n = 15), wound dehiscence (n = 9), and abdominal abscess requiring intervention with drain or return to the operating room (n = 6). On multivariable analysis, independent predictors of severe postoperative complications were anterior or total PE (adjusted odds ratio (aOR): 11.66, 95% CI 2.56-53.18), pre-operative hemoglobin ≤10 mg/dl (aOR 2.70, 95% CI 1.02-7.14) and presence of 3+ comorbidities (aOR: 2.76, 95% CI 1.07-7.10). CONCLUSIONS: Major complications after exenteration are common. Surgical complexity and patient selection play a considerable role in predicting complications. These data can be used to better risk stratify patients undergoing PE.


Assuntos
Neoplasias dos Genitais Femininos/cirurgia , Exenteração Pélvica/efeitos adversos , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
Dig Dis Sci ; 64(12): 3568-3578, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31065898

RESUMO

INTRODUCTION: Despite its initial description over 25 years ago, there is little known about the course of eosinophilic esophagitis (EoE) after an initial course of medical or dietary treatment. We aim to assess the long-term symptomology and quality of life (QoL) metrics in patients 10 years after initial treatment for eosinophilic esophagitis. METHODS: Inclusion criteria: single center study of EoE patients diagnosed over 10 years ago with completion of an 18-question structured telephone interview. A cohort of patient's prospectively underwent an esophageal barium exam, esophageal sponge cytology, and evaluation by a esophagologist at greater than 10 years' time since original diagnosis. RESULTS: A total of 54 patients were included in the study. The average age at follow-up was 55.0, with the majority male (64.8%). At the original diagnosis, 62.9% and 37.0% were initially treated with topical steroids and a proton pump inhibitor (PPI), respectively,compared to 59.3% and 7.4% after 10 years, and 7.4% of patients reported a history of dilatations. Only 11.8% noted avoidance of trigger foods, with 62.7% noting an unlimited diet without caution. QoL decrease secondary to EoE was noted to be trivial to minimal in 56.9% of patients, mild in 19.6%, moderate in 15.7% and severe in 7.8%. In the prospective follow-up cohort, the results of telephone survey results matched the direct physician-obtained interview in 88% of cases. CONCLUSION: Ten years after diagnosis, treated EoE is rarely continually symptomatic, requires mainly PPI-based therapies and is associated with a minimal decrease in QoL scores.


Assuntos
Esofagite Eosinofílica/fisiopatologia , Glucocorticoides/uso terapêutico , Inibidores da Bomba de Prótons/uso terapêutico , Qualidade de Vida , Adulto , Idoso , Dieta , Dilatação , Progressão da Doença , Esofagite Eosinofílica/complicações , Esofagite Eosinofílica/tratamento farmacológico , Esofagite Eosinofílica/patologia , Estenose Esofágica/etiologia , Estenose Esofágica/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
20.
Climacteric ; 22(4): 377-382, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30652511

RESUMO

Purpose: Midlife women frequently experience stress and menopausal symptoms. Mindfulness is thought to mitigate stress by avoiding emotional reactivity and ruminative thinking. We sought to assess the association of mindfulness and stress on menopausal symptoms among midlife women. Materials and methods: In this cross-sectional study, women aged 40-65 years completed questionnaires, including the Menopause Rating Scale (MRS), the Perceived Stress Scale-4 (PSS-4), and the Mindfulness Attention Awareness Scale (MAAS). Linear regression was used to assess the impact of mindfulness and stress on menopausal symptoms with use of univariate and multivariable analyses, adjusting for patient characteristics. Results: In this cohort of 1744 midlife women, higher mindfulness (MAAS) and lower stress (PSS-4) scores correlated independently with lower menopausal symptom (MRS) scores. On multivariable analysis, a significant interaction effect was observed between the MAAS and PSS-4 on the MRS, such that with higher PSS-4 scores, the magnitude of association between the MAAS and lower MRS scores was larger. Conclusion: Among midlife women, higher mindfulness and lower stress correlated with lower menopausal symptom scores independently. Among women experiencing more stress, the magnitude of association between mindfulness and lower menopausal symptom scores was greater, largely driven by psychological subdomain scores. Mindfulness may mitigate menopausal symptoms among midlife women.


Assuntos
Menopausa , Atenção Plena , Estresse Psicológico , Adulto , Idoso , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Psicometria
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