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1.
J Infect Dis ; 230(1): e1-e3, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052706

RESUMO

Infectious disease outbreaks have become increasingly common and require global partnership for adequate preparedness and response. During outbreaks, medical countermeasures (MCMs)-vaccines, therapeutics, and diagnostics-need to reach patients quickly. Recent outbreaks exemplify that products with regulatory approval can expand access and reach patients quicker than investigational products. Unfortunately, insufficient funding globally and differences in funders' prioritization puts gains and future efforts at risk. Of primary concern is (1) lack of a feasible regulatory path and clinical capability to achieve regulatory approval for new MCMs for many diseases; and (2) the need for partners with the mandate, funding, and capabilities to support long-term sustainment of manufacturing capability and stockpiling of licensed products. Without collaboration, the global community runs the risk of losing the capabilities built through years of investment and being underprepared to combat future threats. Synergies between funders are critical to create long-term sustainment of products to ensure access.


Assuntos
Surtos de Doenças , Saúde Global , Cooperação Internacional , Contramedidas Médicas , Humanos , Surtos de Doenças/prevenção & controle , Controle de Doenças Transmissíveis/organização & administração , Controle de Doenças Transmissíveis/métodos , Doenças Transmissíveis/epidemiologia , Vacinas
2.
Clin Infect Dis ; 79(1): 115-121, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38356144

RESUMO

Coronavirus disease 2019 (COVID-19) epidemiology and product landscapes have changed considerably since onset of the pandemic. Safe and effective vaccines and therapeutics are available, but the continual emergence of severe acute respiratory syndrome coronavirus 2 variants introduce limitations in our ability to prevent and treat disease. Project NextGen is a collaboration between the Biomedical Advanced Research and Development Authority, part of the Administration for Strategic Preparedness and Response, and the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health, that is leveraging public-private partnerships to address gaps in the nation's COVID-19 vaccine and therapeutic capabilities. Targeted investments will advance promising next-generation candidates through the most difficult phases of clinical development to encourage further private sector interest for later stage development and commercial availability. New commercial vaccines and therapeutics that are more durable and effective across variants will improve our fight against COVID-19 and transform our response to future threats.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Parcerias Público-Privadas , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , COVID-19/epidemiologia , SARS-CoV-2/imunologia , Estados Unidos , Desenvolvimento de Vacinas , Tratamento Farmacológico da COVID-19 , Antivirais/uso terapêutico , Desenvolvimento de Medicamentos/tendências , Pandemias/prevenção & controle
3.
Mol Phylogenet Evol ; 155: 107036, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33278587

RESUMO

The New World ant genus Myrmecocystus Wesmael, 1838 (Formicidae: Formicinae: Lasiini) is endemic to arid and semi-arid habitats of the western United States and Mexico. Several intriguing life history traits have been described for the genus, the best-known of which are replete workers, that store liquified food in their largely expanded crops and are colloquially referred to as "honeypots". Despite their interesting biology and ecological importance for arid ecosystems, the evolutionary history of Myrmecocystus ants is largely unknown and the current taxonomy presents an unsatisfactory systematic framework. We use ultraconserved elements to infer the evolutionary history of Myrmecocystus ants and provide a comprehensive, dated phylogenetic framework that clarifies the molecular systematics within the genus with high statistical support, reveals cryptic diversity, and reconstructs ancestral foraging activity. Using maximum likelihood, Bayesian and species tree approaches on a data set of 134 ingroup specimens (including samples from natural history collections and type material), we recover largely identical topologies that leave the position of only few clades uncertain and cover the intra- and interspecific variation of 28 of the 29 described and six undescribed species. In addition to traditional support values, such as bootstrap and posterior probability, we quantify genealogical concordance to estimate the effects of conflicting evolutionary histories on phylogenetic inference. Our analyses reveal that the current taxonomic classification of the genus is inconsistent with the molecular phylogenetic inference, and we identify cryptic diversity in seven species. Divergence dating suggests that the split between Myrmecocystus and its sister taxon Lasius occurred in the early Miocene. Crown group Myrmecocystus started diversifying about 14.08 Ma ago when the gradual aridification of the southwestern United States and northern Mexico led to formation of the American deserts and to adaptive radiations of many desert taxa.


Assuntos
Formigas/classificação , Biodiversidade , Filogenia , Animais , Teorema de Bayes , Sequência Conservada/genética , Clima Desértico , Loci Gênicos , Mel , Humanos , Funções Verossimilhança , Sudoeste dos Estados Unidos , Especificidade da Espécie , Fatores de Tempo
4.
Amino Acids ; 50(6): 747-754, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29700652

RESUMO

This study investigated the temporal activation of arginase in obese Zucker rats (ZR) and determined if arginase inhibition prevents the development of hypertension and improves insulin resistance in these animals. Arginase activity, plasma arginine and nitric oxide (NO) concentration, blood pressure, and insulin resistance were measured in lean and obese animals. There was a chronological increase in vascular and plasma arginase activity in obese ZR beginning at 8 weeks of age. The increase in arginase activity in obese animals was associated with a decrease in insulin sensitivity and circulating levels of arginine and NO. The rise in arginase activity also preceded the increase in blood pressure in obese ZR detected at 12 weeks of age. Chronic treatment of 8-week-old obese animals with an arginase inhibitor or L-arginine for 4 weeks prevented the development of hypertension and improved plasma concentrations of arginine and NO. Arginase inhibition also improved insulin sensitivity in obese ZR while L-arginine supplementation had no effect. In conclusion, arginase inhibition prevents the development of hypertension and improves insulin sensitivity while L-arginine administration only mitigates hypertension in obese animals. Arginase represents a promising therapeutic target in ameliorating obesity-associated vascular and metabolic dysfunction.


Assuntos
Arginase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Hipertensão/tratamento farmacológico , Resistência à Insulina , Obesidade/tratamento farmacológico , Animais , Arginase/metabolismo , Arginina/sangue , Hipertensão/sangue , Masculino , Óxido Nítrico/sangue , Obesidade/sangue , Ratos , Ratos Zucker
5.
J Pharmacol Exp Ther ; 360(1): 33-47, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27799294

RESUMO

Synthetic cathinones are components of "bath salts" and have physical and psychologic side effects, including hypertension, paranoia, and hallucinations. Here, we report interactions of 20 "bath salt" components with human dopamine, serotonin, and norepinephrine transporters [human dopamine transporter (hDAT), human serotonin transporter (hSERT), and human norepinephrine transporter (hNET), respectively] heterologously expressed in human embryonic kidney 293 cells. Transporter inhibitors had nanomolar to micromolar affinities (Ki values) at radioligand binding sites, with relative affinities of hDAT>hNET>hSERT for α-pyrrolidinopropiophenone (α-PPP), α-pyrrolidinobutiophenone, α-pyrrolidinohexiophenone, 1-phenyl-2-(1-pyrrolidinyl)-1-heptanone, 3,4-methylenedioxy-α-pyrrolidinopropiophenone, 3,4-methylenedioxy-α-pyrrolidinobutiophenone, 4-methyl-α-pyrrolidinopropiophenone, α-pyrrolidinovalerophenone, 4-methoxy-α-pyrrolidinovalerophenone, α-pyrrolidinopentiothiophenone (alpha-PVT), and α-methylaminovalerophenone, and hDAT>hSERT>hNET for methylenedioxypentedrone. Increasing the α-carbon chain length increased the affinity and potency of the α-pyrrolidinophenones. Uptake inhibitors had relative potencies of hDAT>hNET>hSERT except α-PPP and α-PVT, which had highest potencies at hNET. They did not induce [3H]neurotransmitter release. Substrates can enter presynaptic neurons via transporters, and the substrates methamphetamine and 3,4-methylenedioxymethylamphetamine are neurotoxic. We determined that 3-fluoro-, 4-bromo-, 4-chloro-methcathinone, and 4-fluoroamphetamine were substrates at all three transporters; 5,6-methylenedioxy-2-aminoindane (MDAI) and 4-methylethcathinone (4-MEC) were substrates primarily at hSERT and hNET; and 3,4-methylenedioxy-N-ethylcathinone (ethylone) and 5-methoxy-methylone were substrates only at hSERT and induced [3H]neurotransmitter release. Significant correlations between potencies for inhibition of uptake and for inducing release were observed for these and additional substrates. The excellent correlation of efficacy at stimulating release versus Ki/IC50 ratios suggested thresholds of binding/uptake ratios above which compounds were likely to be substrates. Based on their potencies at hDAT, most of these compounds have potential for abuse and addiction. 4-Bromomethcathinone, 4-MEC, 5-methoxy-methylone, ethylone, and MDAI, which have higher potencies at hSERT than hDAT, may have empathogen psychoactivity.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Neurotransmissores/metabolismo , Proteínas de Transporte de Neurotransmissores/metabolismo , Transporte Biológico/efeitos dos fármacos , Humanos , Ligação Proteica/efeitos dos fármacos , Relação Estrutura-Atividade
6.
Mol Ecol ; 26(24): 6921-6937, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29134724

RESUMO

Leafcutter ants propagate co-evolving fungi for food. The nearly 50 species of leafcutter ants (Atta, Acromyrmex) range from Argentina to the United States, with the greatest species diversity in southern South America. We elucidate the biogeography of fungi cultivated by leafcutter ants using DNA sequence and microsatellite-marker analyses of 474 cultivars collected across the leafcutter range. Fungal cultivars belong to two clades (Clade-A and Clade-B). The dominant and widespread Clade-A cultivars form three genotype clusters, with their relative prevalence corresponding to southern South America, northern South America, Central and North America. Admixture between Clade-A populations supports genetic exchange within a single species, Leucocoprinus gongylophorus. Some leafcutter species that cut grass as fungicultural substrate are specialized to cultivate Clade-B fungi, whereas leafcutters preferring dicot plants appear specialized on Clade-A fungi. Cultivar sharing between sympatric leafcutter species occurs frequently such that cultivars of Atta are not distinct from those of Acromyrmex. Leafcutters specialized on Clade-B fungi occur only in South America. Diversity of Clade-A fungi is greatest in South America, but minimal in Central and North America. Maximum cultivar diversity in South America is predicted by the Kusnezov-Fowler hypothesis that leafcutter ants originated in subtropical South America and only dicot-specialized leafcutter ants migrated out of South America, but the cultivar diversity becomes also compatible with a recently proposed hypothesis of a Central American origin by postulating that leafcutter ants acquired novel cultivars many times from other nonleafcutter fungus-growing ants during their migrations from Central America across South America. We evaluate these biogeographic hypotheses in the light of estimated dates for the origins of leafcutter ants and their cultivars.


Assuntos
Agaricales/genética , Formigas/microbiologia , Coevolução Biológica , Animais , Formigas/classificação , América Central , Marcadores Genéticos , Genética Populacional , Genótipo , Repetições de Microssatélites , América do Norte , Filogenia , Filogeografia , América do Sul , Simbiose
7.
J Natl Compr Canc Netw ; 15(1): 60-87, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28040720

RESUMO

The myelodysplastic syndromes (MDS) comprise a heterogenous group of myeloid disorders with a highly variable disease course. Diagnostic criteria to better stratify patients with MDS continue to evolve, based on morphology, cytogenetics, and the presence of cytopenias. More accurate classification of patients will allow for better treatment guidance. Treatment encompasses supportive care, treatment of anemia, low-intensity therapy, and high-intensity therapy. This portion of the guidelines focuses on diagnostic classification, molecular abnormalities, therapeutic options, and recommended treatment approaches.


Assuntos
Anemia/tratamento farmacológico , Hematínicos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/terapia , Anemia/etiologia , Antineoplásicos/uso terapêutico , Ensaios Clínicos como Assunto , Humanos , Fatores Imunológicos/uso terapêutico , Quimioterapia de Indução/métodos , Oncologia/normas , Mutação , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/mortalidade , Taxa de Sobrevida
8.
Nature ; 466(7306): 632-6, 2010 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-20639864

RESUMO

Understanding the biology that underlies histologically similar but molecularly distinct subgroups of cancer has proven difficult because their defining genetic alterations are often numerous, and the cellular origins of most cancers remain unknown. We sought to decipher this heterogeneity by integrating matched genetic alterations and candidate cells of origin to generate accurate disease models. First, we identified subgroups of human ependymoma, a form of neural tumour that arises throughout the central nervous system (CNS). Subgroup-specific alterations included amplifications and homozygous deletions of genes not yet implicated in ependymoma. To select cellular compartments most likely to give rise to subgroups of ependymoma, we matched the transcriptomes of human tumours to those of mouse neural stem cells (NSCs), isolated from different regions of the CNS at different developmental stages, with an intact or deleted Ink4a/Arf locus (that encodes Cdkn2a and b). The transcriptome of human supratentorial ependymomas with amplified EPHB2 and deleted INK4A/ARF matched only that of embryonic cerebral Ink4a/Arf(-/-) NSCs. Notably, activation of Ephb2 signalling in these, but not other, NSCs generated the first mouse model of ependymoma, which is highly penetrant and accurately models the histology and transcriptome of one subgroup of human supratentorial tumour. Further, comparative analysis of matched mouse and human tumours revealed selective deregulation in the expression and copy number of genes that control synaptogenesis, pinpointing disruption of this pathway as a critical event in the production of this ependymoma subgroup. Our data demonstrate the power of cross-species genomics to meticulously match subgroup-specific driver mutations with cellular compartments to model and interrogate cancer subgroups.


Assuntos
Compartimento Celular , Modelos Animais de Doenças , Ependimoma/genética , Ependimoma/patologia , Genômica , Mutação/genética , Animais , Sistema Nervoso Central/citologia , Sistema Nervoso Central/crescimento & desenvolvimento , Neoplasias do Sistema Nervoso Central/classificação , Neoplasias do Sistema Nervoso Central/genética , Neoplasias do Sistema Nervoso Central/patologia , Ependimoma/classificação , Deleção de Genes , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genes p16 , Humanos , Camundongos , Modelos Biológicos , Polimorfismo de Nucleotídeo Único/genética , Receptor EphB2/genética , Receptor EphB2/metabolismo , Especificidade da Espécie , Células-Tronco/citologia , Células-Tronco/metabolismo , Sinapses/metabolismo
9.
Proc Natl Acad Sci U S A ; 110(43): 17398-403, 2013 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-24101479

RESUMO

Environmental sensor networks are developing rapidly to assess changes in ecosystems and their services. Some ecosystem changes involve thresholds, and theory suggests that statistical indicators of changing resilience can be detected near thresholds. We examined the capacity of environmental sensors to assess resilience during an experimentally induced transition in a whole-lake manipulation. A trophic cascade was induced in a planktivore-dominated lake by slowly adding piscivorous bass, whereas a nearby bass-dominated lake remained unmanipulated and served as a reference ecosystem during the 4-y experiment. In both the manipulated and reference lakes, automated sensors were used to measure variables related to ecosystem metabolism (dissolved oxygen, pH, and chlorophyll-a concentration) and to estimate gross primary production, respiration, and net ecosystem production. Thresholds were detected in some automated measurements more than a year before the completion of the transition to piscivore dominance. Directly measured variables (dissolved oxygen, pH, and chlorophyll-a concentration) related to ecosystem metabolism were better indicators of the approaching threshold than were the estimates of rates (gross primary production, respiration, and net ecosystem production); this difference was likely a result of the larger uncertainties in the derived rate estimates. Thus, relatively simple characteristics of ecosystems that were observed directly by the sensors were superior indicators of changing resilience. Models linked to thresholds in variables that are directly observed by sensor networks may provide unique opportunities for evaluating resilience in complex ecosystems.


Assuntos
Bass/crescimento & desenvolvimento , Ecossistema , Peixes/crescimento & desenvolvimento , Lagos , Zooplâncton/crescimento & desenvolvimento , Algoritmos , Animais , Biomassa , Clorofila/metabolismo , Clorofila A , Monitorização de Parâmetros Ecológicos/métodos , Peixes/classificação , Concentração de Íons de Hidrogênio , Modelos Biológicos , Oxigênio/metabolismo , Dinâmica Populacional , Fatores de Tempo , Zooplâncton/classificação
10.
BMC Evol Biol ; 15: 183, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26338531

RESUMO

BACKGROUND: A fundamental and enduring problem in evolutionary biology is to understand how populations differentiate in the wild, yet little is known about what role organismal development plays in this process. Organismal development integrates environmental inputs with the action of gene regulatory networks to generate the phenotype. Core developmental gene networks have been highly conserved for millions of years across all animals, and therefore, organismal development may bias variation available for selection to work on. Biased variation may facilitate repeatable phenotypic responses when exposed to similar environmental inputs and ecological changes. To gain a more complete understanding of population differentiation in the wild, we integrated evolutionary developmental biology with population genetics, morphology, paleoecology and ecology. This integration was made possible by studying how populations of the ant species Monomorium emersoni respond to climatic and ecological changes across five 'Sky Islands' in Arizona, which are mountain ranges separated by vast 'seas' of desert. Sky Islands represent a replicated natural experiment allowing us to determine how repeatable is the response of M. emersoni populations to climate and ecological changes at the phenotypic, developmental, and gene network levels. RESULTS: We show that a core developmental gene network and its phenotype has kept pace with ecological and climate change on each Sky Island over the last ~90,000 years before present (BP). This response has produced two types of evolutionary change within an ant species: one type is unpredictable and contingent on the pattern of isolation of Sky lsland populations by climate warming, resulting in slight changes in gene expression, organ growth, and morphology. The other type is predictable and deterministic, resulting in the repeated evolution of a novel wingless queen phenotype and its underlying gene network in response to habitat changes induced by climate warming. CONCLUSION: Our findings reveal dynamics of developmental gene network evolution in wild populations. This holds important implications: (1) for understanding how phenotypic novelty is generated in the wild; (2) for providing a possible bridge between micro- and macroevolution; and (3) for understanding how development mediates the response of organisms to past, and potentially, future climate change.


Assuntos
Formigas/genética , Evolução Biológica , Mudança Climática , Redes Reguladoras de Genes , Animais , Formigas/fisiologia , Arizona , Ecossistema , Genes Controladores do Desenvolvimento , Genética Populacional
11.
J Natl Compr Canc Netw ; 13(10): 1240-79, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26483064

RESUMO

Treatment of acute lymphoblastic leukemia (ALL) continues to advance, as evidenced by the improved risk stratification of patients and development of newer treatment options. Identification of ALL subtypes based on immunophenotyping and cytogenetic and molecular markers has resulted in the inclusion of Philadelphia-like ALL and early T-cell precursor ALL as subtypes that affect prognosis. Identification of Ikaros mutations has also emerged as a prognostic factor. In addition to improved prognostication, treatment options for patients with ALL have expanded, particularly with regard to relapsed/refractory ALL. Continued development of second-generation tyrosine kinase inhibitors and the emergence of immunotherapy, including blinatumomab and chimeric antigen receptor T-cell therapy, have improved survival. Furthermore, incorporation of minimal residual disease (MRD) monitoring has shown insight into patient outcomes and may lead to treatment modification or alternative treatment strategies in select populations. This excerpt focuses on the sections of the ALL guidelines specific to clinical presentation and diagnosis, treatment of relapsed/refractory ALL, and incorporation of MRD monitoring. To view the most recent complete version of these guidelines, visit NCCN.org.


Assuntos
Guias de Prática Clínica como Assunto , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Fatores de Risco
12.
Nature ; 459(7244): 270-3, 2009 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-19357645

RESUMO

Preventing and delaying the emergence of drug resistance is an essential goal of antimalarial drug development. Monotherapy and highly mutable drug targets have each facilitated resistance, and both are undesirable in effective long-term strategies against multi-drug-resistant malaria. Haem remains an immutable and vulnerable target, because it is not parasite-encoded and its detoxification during haemoglobin degradation, critical to parasite survival, can be subverted by drug-haem interaction as in the case of quinolines and many other drugs. Here we describe a new antimalarial chemotype that combines the haem-targeting character of acridones, together with a chemosensitizing component that counteracts resistance to quinoline antimalarial drugs. Beyond the essential intrinsic characteristics common to deserving candidate antimalarials (high potency in vitro against pan-sensitive and multi-drug-resistant Plasmodium falciparum, efficacy and safety in vivo after oral administration, inexpensive synthesis and favourable physicochemical properties), our initial lead, T3.5 (3-chloro-6-(2-diethylamino-ethoxy)-10-(2-diethylamino-ethyl)-acridone), demonstrates unique synergistic properties. In addition to 'verapamil-like' chemosensitization to chloroquine and amodiaquine against quinoline-resistant parasites, T3.5 also results in an apparently mechanistically distinct synergism with quinine and with piperaquine. This synergy, evident in both quinoline-sensitive and quinoline-resistant parasites, has been demonstrated both in vitro and in vivo. In summary, this innovative acridone design merges intrinsic potency and resistance-counteracting functions in one molecule, and represents a new strategy to expand, enhance and sustain effective antimalarial drug combinations.


Assuntos
Acridonas/farmacologia , Antimaláricos/farmacologia , Descoberta de Drogas , Plasmodium falciparum/efeitos dos fármacos , Acridonas/análise , Acridonas/metabolismo , Animais , Antimaláricos/análise , Antimaláricos/metabolismo , Resistência a Medicamentos/efeitos dos fármacos , Sinergismo Farmacológico , Heme/antagonistas & inibidores , Heme/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Mutação/genética , Plasmodium falciparum/genética , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/metabolismo , Plasmodium yoelii/efeitos dos fármacos , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Quinina/farmacologia , Quinolinas/farmacologia , Trofozoítos/metabolismo , Verapamil/farmacologia
13.
Zootaxa ; 3972(2): 231-49, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26249490

RESUMO

We revise species of seed-harvester ants in the genus Pogonomyrmex (subfamily Myrmicinae) that occur on the Caribbean island of Hispaniola. Three species are recognized: P. aterrimus Wheeler (new status), P. saucius Wheeler and Mann, and P. schmitti Forel. Pogonomyrmex schmitti sublaevigatus Wheeler (= schmitti) and P. schmitti darlingtoni Wheeler (= aterrimus) are synonomized. We also describe the queen of P. aterrimus and P. saucius, and provide information on biology, distribution maps, and a key to workers and queens.


Assuntos
Formigas/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Formigas/anatomia & histologia , Formigas/crescimento & desenvolvimento , Tamanho Corporal , Ecossistema , Feminino , Masculino , Tamanho do Órgão
14.
Artigo em Inglês | MEDLINE | ID: mdl-24322558

RESUMO

We combined behavioral analyses in the laboratory and field to investigate chemical communication in the formation of foraging columns in two Nearctic seed harvesting ants, Messor pergandei and Messor andrei. We demonstrate that both species use poison gland secretions to lay recruitment trails. In M. pergandei, the recruitment effect of the poison gland is enhanced by adding pygidial gland secretions. The poison glands of both species contain 1-phenyl ethanol. Minute quantities (3 µl of a 0.1 ppm solution) of 1-phenyl ethanol drawn out along a 40 cm long trail released trail following behavior in M. pergandei, while M. andrei required higher concentrations (0.5-1 ppm). Messor pergandei workers showed weak trail following to 5 ppm trails of the pyrazines 2,5-dimethylpyrazine and 2,3,5-trimethylpyrazine, whereas M. andrei workers showed no behavioral response. Minute quantities of pyrazines were detected in M. pergandei but not in M. andrei poison glands using single ion monitoring gas chromatography-mass spectrometry.


Assuntos
Agressão , Comunicação Animal , Formigas/química , Formigas/fisiologia , Feromônios , Agressão/efeitos dos fármacos , Animais , Álcoois Benzílicos/farmacologia , Relação Dose-Resposta a Droga , Feromônios/farmacologia , Especificidade da Espécie
15.
Zootaxa ; 3646: 201-27, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26213760

RESUMO

Pogonomyrmex magnacanthus Cole was described as a distinct species; unusually large eyes and a high ocular index (maximum eye diameter/head width) were listed as diagnostic characters. However, examination of numerous series of P. magnacanthus revealed that both characters were highly variable, and that these series consisted of P. magnacanthus plus an undescribed species, Pogonomyrmex hoelldobleri Johnson, Overson & Moreau sp. nov. This paper describes all three castes of P. hoelldobleri as well as the alate queen of P mohavensis, which is very similar to that of P. hoelldobleri. A molecular phylogeny that consisted of 3,703 bp from one mitochondrial and five nuclear gene fragments-supported the monophyly of P. hoelldobleri, P. magnacanthus, and P mohavensis. Pogonomyrnex inagnacanthus can be separated from other P. californicus group species based on: (1) its unusually large eyes, (2) a high ocular index, and (3) a malar ratio that is typically < or = 1.0. Pogonomyrmex hoelldobleri can be separated from other P. californicus group species based on the combination of: (1) eyes not unusually large, (2) cephalic rugae not forming circumocular whorls, but rather converging posterior to the eyes, usually near the vertex, (3) mandible with seven teeth, and (4) interrugal spaces on pronotal sides moderately to strongly granulate, dull to weakly shining. Pogonomyrmex mohavensis can be separated from other P. californicus group species based on the combination of: (1) eyes not unusually large, (2) cephalic rugae not forming circumocular whorls, but rather extending more or less directly to the vertex or converging only slightly near the vertex, (3) mandible with six teeth (a seventh sometimes occurs as a denticle between the basal and sub-basal teeth), and (4) interrugal spaces on pronotal sides smooth and shining to weakly punctate and moderately shining. We also provide field observations and distribution maps for P. magnacanthus, P. hoelldobleri, and P. mohavensis, and an updated key to P californicus group species that occur in central and western North America.


Assuntos
Formigas/classificação , Animais , Formigas/anatomia & histologia , Formigas/genética , Biodiversidade , Clima Desértico , Feminino , Masculino , México , Filogenia , Sudoeste dos Estados Unidos
16.
Bioinformatics ; 27(15): 2098-103, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21697127

RESUMO

MOTIVATION: Animal models play a pivotal role in translation biomedical research. The scientific value of an animal model depends on how accurately it mimics the human disease. In principle, microarrays collect the necessary data to evaluate the transcriptomic fidelity of an animal model in terms of the similarity of expression with the human disease. However, statistical methods for this purpose are lacking. RESULTS: We develop the agreement of differential expression (AGDEX) procedure to measure and determine the statistical significance of the similarity of the results of two experiments that measure differential expression across two groups. AGDEX defines a metric of agreement and determines statistical significance by permutation of each experiment's group labels. Additionally, AGDEX performs a comprehensive permutation-based analysis of differential expression for each experiment, including gene-set analyses and meta-analytic integration of results across studies. As an example, we show how AGDEX was recently used to evaluate the similarity of the transcriptome of a novel model of the brain tumor ependymoma in mice to that of a subtype of the human disease. This result, combined with other observations, helped us to infer the cell of origin of this devastating human cancer. AVAILABILITY: An R package is currently available from www.stjuderesearch.org/site/depts/biostats/agdex and will shortly be available from www.bioconductor.org.


Assuntos
Perfilação da Expressão Gênica/métodos , Genômica/métodos , Modelos Estatísticos , Animais , Biologia Computacional/métodos , Modelos Animais de Doenças , Ependimoma/genética , Humanos , Metanálise como Assunto , Camundongos
17.
Hum Vaccin Immunother ; 18(6): 2129930, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36302122

RESUMO

The COVID-19 pandemic profoundly disrupted, and, out of necessity, accelerated innovation of research and development of medical countermeasures to combat COVID-19. Although countermeasures were developed with unprecedented speed as a result of decades of long-term Federal investments in platform technologies and existing partnerships, the pandemic also revealed gaps in our preparedness and response capabilities that threaten our readiness posture. Challenges include limited federal funding that hinders sustainable development and manufacturing of, and equitable access to, medical countermeasures. Here we discuss lessons learned from the development and production efforts of medical countermeasures, such as vaccines and immunotherapeutics, to combat COVID-19. This commentary highlights some of the key gaps and challenges that must be addressed to ensure preparation for future outbreaks caused by viruses of pandemic potential.


Assuntos
COVID-19 , Vacinas , Humanos , Pandemias/prevenção & controle , COVID-19/prevenção & controle , Surtos de Doenças/prevenção & controle
18.
PLoS One ; 17(9): e0257779, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36137088

RESUMO

The eyes of insects display an incredible diversity of adaptations to enhance vision across the gamut of light levels that they experience. One commonly studied contrast is the difference in eye structure between nocturnal and diurnal species, with nocturnal species typically having features that enhance eye sensitivity such as larger eyes, larger eye facets, and larger ocelli. In this study, we compared eye structure between workers of closely related nocturnal and diurnal above ground foraging ant species (Hymenoptera: Formicidae) in four genera (Myrmecocystus, Aphaenogaster, Temnothorax, Veromessor). In all four genera, nocturnal species tend to have little cuticular pigment (pale), while diurnal species are heavily pigmented (dark), hence we could use cuticle coloration as a surrogate for activity pattern. Across three genera (Myrmecocystus, Aphaenogaster, Temnothorax), pale species, as expected for nocturnally active animals, had larger eyes, larger facet diameters, and larger visual spans compared to their dark, more day active congeners. This same pattern occurred for one pale species of Veromessor, but not the other. There were no consistent differences between nocturnal and diurnal species in interommatidial angles and eye parameters both within and among genera. Hence, the evolution of eye features that enhance sensitivity in low light levels do not appear to have consistent correlated effects on features related to visual acuity. A survey across several additional ant genera found numerous other pale species with enlarged eyes, suggesting these traits evolved multiple times within and across genera. We also compared the size of the anterior ocellus in workers of pale versus dark species of Myrmecocystus. In species with larger workers, the anterior ocellus was smaller in pale than in dark species, but this difference mostly disappeared for species with smaller workers. Presence of the anterior ocellus also was size-dependent in the two largest pale species.


Assuntos
Formigas , Adaptação Fisiológica , Animais , Olho , Visão Ocular , Acuidade Visual
19.
Zootaxa ; 5206(1): 1-115, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37045410

RESUMO

This paper provides a taxonomic revision and a review of the biology for the 10 species of North American seed-harvester ants in the genus Veromessor. Two new synonomies are proposed: V. julianus subsp. clarior W.M. Wheeler and Creighton 1934 new synonym and V. julianus subsp. manni W.M. Wheeler and Creighton 1934 new synonym are synonomized under V. julianus (Pergande, 1894). One new species is described: V. pseudolariversi new species (worker, queen, male), as a result of splitting V. lariversi Smith into two species based on morphological and genetic differences. We also diagnose previously undescribed queens and males for the following species: V. andrei (male), V. chamberlini (queen, male), V. chicoensis (queen, male), V. julianus (queen, male), and V. stoddardi (queen, male). Information on biology of each species is summarized, along with distribution maps and keys to workers, queens, and males. We then discuss the biology for species of Veromessor, focusing on several morphological and ecological traits that display strong variation across the relatively low number of species (10) in the genus. Morphological traits include degree of psammophore development, propodeal spine length, eye size and structure, and worker polymorphism and worker body size, while ecological traits include colony size and foraging method, seasonality of mating flights, mating frequency, and queen size and colony founding strategy.


Assuntos
Formigas , Animais , Masculino , Formigas/genética , Biologia , Tamanho Corporal , Tamanho do Órgão
20.
Sci Adv ; 8(31): eabp9908, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35921404

RESUMO

Invertebrates constitute the majority of animal species and are critical for ecosystem functioning and services. Nonetheless, global invertebrate biodiversity patterns and their congruences with vertebrates remain largely unknown. We resolve the first high-resolution (~20-km) global diversity map for a major invertebrate clade, ants, using biodiversity informatics, range modeling, and machine learning to synthesize existing knowledge and predict the distribution of undiscovered diversity. We find that ants and different vertebrate groups have distinct features in their patterns of richness and rarity, underscoring the need to consider a diversity of taxa in conservation. However, despite their phylogenetic and physiological divergence, ant distributions are not highly anomalous relative to variation among vertebrate clades. Furthermore, our models predict that rarity centers largely overlap (78%), suggesting that general forces shape endemism patterns across taxa. This raises confidence that conservation of areas important for small-ranged vertebrates will benefit invertebrates while providing a "treasure map" to guide future discovery.


Assuntos
Formigas , Animais , Formigas/fisiologia , Biodiversidade , Ecossistema , Invertebrados , Filogenia , Vertebrados
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