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1.
Nature ; 602(7895): 63-67, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110756

RESUMO

Electrically charged particles can be created by the decay of strong enough electric fields, a phenomenon known as the Schwinger mechanism1. By electromagnetic duality, a sufficiently strong magnetic field would similarly produce magnetic monopoles, if they exist2. Magnetic monopoles are hypothetical fundamental particles that are predicted by several theories beyond the standard model3-7 but have never been experimentally detected. Searching for the existence of magnetic monopoles via the Schwinger mechanism has not yet been attempted, but it is advantageous, owing to the possibility of calculating its rate through semi-classical techniques without perturbation theory, as well as that the production of the magnetic monopoles should be enhanced by their finite size8,9 and strong coupling to photons2,10. Here we present a search for magnetic monopole production by the Schwinger mechanism in Pb-Pb heavy ion collisions at the Large Hadron Collider, producing the strongest known magnetic fields in the current Universe11. It was conducted by the MoEDAL experiment, whose trapping detectors were exposed to 0.235 per nanobarn, or approximately 1.8 × 109, of Pb-Pb collisions with 5.02-teraelectronvolt center-of-mass energy per collision in November 2018. A superconducting quantum interference device (SQUID) magnetometer scanned the trapping detectors of MoEDAL for the presence of magnetic charge, which would induce a persistent current in the SQUID. Magnetic monopoles with integer Dirac charges of 1, 2 and 3 and masses up to 75 gigaelectronvolts per speed of light squared were excluded by the analysis at the 95% confidence level. This provides a lower mass limit for finite-size magnetic monopoles from a collider search and greatly extends previous mass bounds.

2.
PLoS Comput Biol ; 20(2): e1011270, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38324613

RESUMO

CyVerse, the largest publicly-funded open-source research cyberinfrastructure for life sciences, has played a crucial role in advancing data-driven research since the 2010s. As the technology landscape evolved with the emergence of cloud computing platforms, machine learning and artificial intelligence (AI) applications, CyVerse has enabled access by providing interfaces, Software as a Service (SaaS), and cloud-native Infrastructure as Code (IaC) to leverage new technologies. CyVerse services enable researchers to integrate institutional and private computational resources, custom software, perform analyses, and publish data in accordance with open science principles. Over the past 13 years, CyVerse has registered more than 124,000 verified accounts from 160 countries and was used for over 1,600 peer-reviewed publications. Since 2011, 45,000 students and researchers have been trained to use CyVerse. The platform has been replicated and deployed in three countries outside the US, with additional private deployments on commercial clouds for US government agencies and multinational corporations. In this manuscript, we present a strategic blueprint for creating and managing SaaS cyberinfrastructure and IaC as free and open-source software.


Assuntos
Inteligência Artificial , Software , Humanos , Computação em Nuvem , Editoração
3.
Mol Biol Evol ; 40(9)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37695804

RESUMO

Uric acid is the main means of nitrogen excretion in uricotelic vertebrates (birds and reptiles) and the end product of purine catabolism in humans and a few other mammals. While uricase is inactivated in mammals unable to degrade urate, the presence of orthologous genes without inactivating mutations in avian and reptilian genomes is unexplained. Here we show that the Gallus gallus gene we name cysteine-rich urate oxidase (CRUOX) encodes a functional protein representing a unique case of cysteine enrichment in the evolution of vertebrate orthologous genes. CRUOX retains the ability to catalyze urate oxidation to hydrogen peroxide and 5-hydroxyisourate (HIU), albeit with a 100-fold reduced efficiency. However, differently from all uricases hitherto characterized, it can also facilitate urate regeneration from HIU, a catalytic property that we propose depends on its enrichment in cysteine residues. X-ray structural analysis highlights differences in the active site compared to known orthologs and suggests a mechanism for cysteine-mediated self-aggregation under H2O2-oxidative conditions. Cysteine enrichment was concurrent with the transition to uricotelism and a shift in gene expression from the liver to the skin where CRUOX is co-expressed with ß-keratins. Therefore, the loss of urate degradation in amniotes has followed opposite evolutionary trajectories: while uricase has been eliminated by pseudogenization in some mammals, it has been repurposed as a redox-sensitive enzyme in the reptilian skin.


Assuntos
Cisteína , Répteis , Pele , Urato Oxidase , Animais , Cisteína/genética , Peróxido de Hidrogênio , Pele/enzimologia , Urato Oxidase/genética , Urato Oxidase/metabolismo , Ácido Úrico , Galinhas/genética , Répteis/genética , Répteis/metabolismo
4.
Lupus ; 32(6): 737-745, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37036020

RESUMO

OBJECTIVE: During the COVID-19 pandemic, many research studies were adapted, including our longitudinal study examining cognitive impairment (CI) in systemic lupus erythematosus (SLE). Cognitive testing was switched from in-person to virtual. This analysis aimed to determine if the administration method (in-person vs. virtual) of the ACR-neuropsychological battery (ACR-NB) affected participant cognitive performance and classification. METHODS: Data from our multi-visit, SLE CI study included demographic, clinical, and psychiatric characteristics, and the modified ACR-NB. Three analyses were undertaken for cognitive performance: (1) all visits, (2) non-CI group visits only and (3) intra-individual comparisons. A retrospective preferences questionnaire was given to participants who completed the ACR-NB both in-person and virtually. RESULTS: We analysed 328 SLE participants who had 801 visits (696 in-person and 105 virtual). Demographic, clinical, and psychiatric characteristics were comparable except for ethnicity, anxiety and disease-related damage. Across all three comparisons, six tests were consistently statistically significantly different. CI classification changed in 11/71 (15%) participants. 45% of participants preferred the virtual administration method and 33% preferred in-person. CONCLUSIONS: Of the 19 tests in the ACR-NB, we identified one or more problems with eight (42%) tests when moving from in-person to virtual administration. As the use of virtual cognitive testing will likely increase, these issues need to be addressed - potentially by validating a virtual version of the ACR-NB. Until then, caution must be taken when directly comparing virtual to in-person test results. If future studies use a mixed administration approach, this should be accounted for during analysis.


Assuntos
COVID-19 , Lúpus Eritematoso Sistêmico , Reumatologia , Humanos , Estados Unidos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/psicologia , Estudos Retrospectivos , Estudos Longitudinais , Pandemias , COVID-19/complicações , Cognição
5.
Angew Chem Int Ed Engl ; 62(10): e202216309, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36622129

RESUMO

Propylene gas is produced worldwide by steam cracking on million-metric-ton scale per year. It serves as a valuable starting material for π-bond functionalization but is rarely applied in transition metal-catalyzed allylic C-H functionalization for fine chemical synthesis. Herein, we report that a newly-developed cationic cyclopentadienyliron dicarbonyl complex allows for the conversion of propylene to its allylic C-C bond coupling products under catalytic conditions. This approach was also found applicable to the allylic functionalization of simple α-olefins with distinctive branched selectivity. Experimental and computational mechanistic studies supported the allylic deprotonation of the metal-coordinated alkene as the turnover-limiting step and led to insights into the multifaceted roles of the newly designed ligand in promoting allylic C-H functionalization with enhanced reactivity and stereoselectivity.

6.
Mol Med ; 28(1): 61, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35659174

RESUMO

Botulinum neurotoxins (BoNTs) are highly potent, select agent toxins that inhibit neurotransmitter release at motor nerve terminals, causing muscle paralysis and death by asphyxiation. Other than post-exposure prophylaxis with antitoxin, the only treatment option for symptomatic botulism is intubation and supportive care until recovery, which can require weeks or longer. In previous studies, we reported the FDA-approved drug 3,4-diaminopyridine (3,4-DAP) reverses early botulism symptoms and prolongs survival in lethally intoxicated mice. However, the symptomatic benefits of 3,4-DAP are limited by its rapid clearance. Here we investigated whether 3,4-DAP could sustain symptomatic benefits throughout the full course of respiratory paralysis in lethally intoxicated rats. First, we confirmed serial injections of 3,4-DAP stabilized toxic signs and prolonged survival in rats challenged with 2.5 LD50 BoNT/A. Rebound of toxic signs and death occurred within hours after the final 3,4-DAP treatment, consistent with the short half-life of 3,4-DAP in rats. Based on these data, we next investigated whether the therapeutic benefits of 3,4-DAP could be sustained throughout the course of botulism by continuous infusion. To ensure administration of 3,4-DAP at clinically relevant doses, three infusion dose rates (0.5, 1.0 and 1.5 mg/kg∙h) were identified that produced steady-state serum levels of 3,4-DAP consistent with clinical dosing. We then compared dose-dependent effects of 3,4-DAP on toxic signs and survival in rats intoxicated with 2.5 LD50 BoNT/A. In contrast to saline vehicle, which resulted in 100% mortality, infusion of 3,4-DAP at ≥ 1.0 mg/kg∙h from 1 to 14 d after intoxication produced 94.4% survival and full resolution of toxic signs, without rebound of toxic signs after infusion was stopped. In contrast, withdrawal of 3,4-DAP infusion at 5 d resulted in re-emergence of toxic sign and death within 12 h, confirming antidotal outcomes require sustained 3,4-DAP treatment for longer than 5 d after intoxication. We exploited this novel survival model of lethal botulism to explore neurophysiological parameters of diaphragm paralysis and recovery. While neurotransmission was nearly eliminated at 5 d, neurotransmission was significantly improved at 21 d in 3,4-DAP-infused survivors, although still depressed compared to naïve rats. 3,4-DAP is the first small molecule to reverse systemic paralysis and promote survival in animal models of botulism, thereby meeting a critical treatment need that is not addressed by post-exposure prophylaxis with conventional antitoxin. These data contribute to a growing body of evidence supporting the use of 3,4-DAP to treat clinical botulism.


Assuntos
Antitoxinas , Botulismo , Amifampridina/uso terapêutico , Animais , Antídotos/farmacologia , Antídotos/uso terapêutico , Antitoxinas/uso terapêutico , Botulismo/tratamento farmacológico , Camundongos , Paralisia/tratamento farmacológico , Ratos
7.
Ann Oncol ; 33(8): 814-823, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35513244

RESUMO

BACKGROUND: Difference in pathologic complete response (pCR) rate after neoadjuvant chemotherapy does not capture the impact of treatment on downstaging of residual cancer in the experimental arm. We developed a method to compare the entire distribution of residual cancer burden (RCB) values between clinical trial arms to better quantify the differences in cytotoxic efficacy of treatments. PATIENTS AND METHODS: The Treatment Efficacy Score (TES) reflects the area between the weighted cumulative distribution functions of RCB values from two trial arms. TES is based on a modified Kolmogorov-Smirnov test with added weight function to capture the importance of high RCB values and uses the area under the difference between two distribution functions as a statistical metric. The higher the TES the greater the shift to lower RCB values in the experimental arm. We developed TES from the durvalumab + olaparib arm (n = 72) and corresponding controls (n = 282) of the I-SPY2 trial. The 11 other experimental arms and control cohorts (n = 947) were used as validation sets to assess the performance of TES. We compared TES to Kolmogorov-Smirnov, Mann-Whitney, and Fisher's exact tests to identify trial arms with higher cytotoxic efficacy and assessed associations with trial arm level survival differences. Significance was assessed with a permutation test. RESULTS: In the validation set, TES identified arms with a higher pCR rate but was more accurate to identify regimens as less effective if treatment did not reduce the frequency of high RCB values, even if the pCR rate improved. The correlation between TES and survival was higher than the correlation between the pCR rate difference and survival. CONCLUSIONS: TES quantifies the difference between the entire distribution of pathologic responses observed in trial arms and could serve as a better early surrogate to predict trial arm level survival differences than pCR rate difference alone.


Assuntos
Antineoplásicos , Neoplasias da Mama , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/patologia , Feminino , Humanos , Terapia Neoadjuvante , Neoplasia Residual/tratamento farmacológico , Neoplasia Residual/patologia , Resultado do Tratamento
8.
Exp Parasitol ; 239: 108292, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35679969

RESUMO

The larval stage of the one-host tick, Dermacentor albipictus Packard (Acari: Ixodidae), the winter tick, is spent aggregated on the ground in summer until they quest for hosts in the autumn. Metarhizium brunneum (Petch) and Beauveria bassiana (Balsamo-Crivelli) Vuillemin are promising fungal biocontrol agents of ticks. The success of tick biocontrol using entomopathogenic fungi relies on infective propagule contact with a susceptible host at the right time within their life cycle and stage. The susceptibility of various-age D. albipictus larvae to commercial isolates of M. brunneum strain F52 (Mb-F52) and B. bassiana strain GHA (Bb-GHA) was assessed over a three-week period after contact with surfaces treated with 1.3 × 106 conidia/cm2. Larvae of four ages were examined (a) upon eclosion from eggs, (b) 2-weeks, (c) 1.5-months and (d) 3-months-old. Mortality of larvae exposed to fungus-treated surfaces ranged from 4 to 51% for Bb-GHA and 64-100% for Mb-F52 after three weeks. Significantly greater mortality was observed when larvae were exposed to Mb-F52 than Bb-GHA. Larval susceptibility was significantly greater within 2 weeks of eclosion from eggs and after 3 months of age. These results demonstrate the varying susceptibility of larvae to mycoacaricides at different times within their non-parasitic larval life stage.


Assuntos
Beauveria , Dermacentor , Ixodidae , Animais , Larva/microbiologia , Controle Biológico de Vetores/métodos
9.
Proc Natl Acad Sci U S A ; 116(23): 11165-11170, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31110011

RESUMO

The source of water (H2O) and hydroxyl radicals (OH), identified on the lunar surface, represents a fundamental, unsolved puzzle. The interaction of solar-wind protons with silicates and oxides has been proposed as a key mechanism, but laboratory experiments yield conflicting results that suggest that proton implantation alone is insufficient to generate and liberate water. Here, we demonstrate in laboratory simulation experiments combined with imaging studies that water can be efficiently generated and released through rapid energetic heating like micrometeorite impacts into anhydrous silicates implanted with solar-wind protons. These synergistic effects of solar-wind protons and micrometeorites liberate water at mineral temperatures from 10 to 300 K via vesicles, thus providing evidence of a key mechanism to synthesize water in silicates and advancing our understanding on the origin of water as detected on the Moon and other airless bodies in our solar system such as Mercury and asteroids.

10.
J Environ Manage ; 319: 115676, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35839648

RESUMO

Providing sufficient benefits to local people can be an important component of effective and equitable conservation, especially where local communities face substantial opportunity costs or disbenefits from conservation. However, the distribution of benefits to local people is often inadequate or inequitable. In this study we investigated the heterogeneity in the extent to which people living near Hwange National Park (HNP), Zimbabwe, perceive benefit from the presence of the park. Specifically, we examined the relationships between a diverse set of candidate predictor variables and perceived benefit from HNP. Our candidate predictor variables broadly relate to personal assets, social capital, value orientation, fear of lions, and belief and participation in human-wildlife conflict mitigation schemes. One third of respondents reported that their household experienced at least some benefits from HNP. Of all respondents, 6% perceived their household to benefit strongly from HNP and 2% very strongly. Livestock loss to wildlife was the most important factor for predicting perceived benefit, with those suffering more loss less likely to perceive benefit. Multiple demographic factors predicted perceived benefit with, for instance, older people and those with less education perceiving less benefit. Employment in conservation-related work positively affected perceived benefit, whereas fear of lions had a negative impact. Social capital appeared to have a positive influence on perceived benefit from HNP. The relationship between social capital and perceived benefit was positive and plateauing, which suggests that social capital is especially impactful on the benefit perceived by individuals reporting the least social capital. We also found a positive association between belief in compensation schemes and perceived benefit from HNP. We posit hypotheses for this association but are unable to determine the underlying drivers of this relationship. Finally, participation in the community guardians programme, a human-lion conflict mitigation programme, was positively related to perceived benefit from HNP. Thus, our findings emphasise the value of considering a diverse array of factors when investigating park-people relationships and yield insights for improving the equitability of conservation in and around HNP and similar systems.


Assuntos
Gado , Capital Social , Idoso , Animais , Animais Selvagens , Conservação dos Recursos Naturais , Medo , Humanos
11.
Thorax ; 76(11): 1124-1130, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33863828

RESUMO

BACKGROUND: Pulse arrival time (PAT) is commonly used to estimate blood pressure response. We hypothesised that PAT response to obstructive respiratory events would be associated with increased cardiovascular risk in people with obstructive sleep apnoea. METHODS: PAT, defined as the time interval between electrocardiography R wave and pulse arrival by photoplethysmography, was measured in the Multi-Ethnic Study of Atherosclerosis Sleep study participants. The PAT response to apnoeas/hypopnoeas was defined as the area under the PAT waveform following respiratory events. Cardiovascular outcomes included markers of subclinical cardiovascular disease (CVD): left ventricular mass, carotid plaque burden score and coronary artery calcification (CAC) (cross-sectional) and incident composite CVD events (prospective). Multivariable logistic and Cox proportional hazard regressions were performed. RESULTS: A total of 1407 participants (mean age 68.4 years, female 47.5%) were included. Higher PAT response (per 1 SD increase) was associated with higher left ventricular mass (5.7 g/m2 higher in fourth vs first quartile, p<0.007), higher carotid plaque burden score (0.37 higher in fourth vs first quartile, p=0.02) and trended to greater odds of CAC (1.44, 95% CI 0.98 to 2.15, p=0.06). A total of 65 incident CVD events were observed over the mean of 4.1 (2.6) years follow-up period. Higher PAT response was associated with increased future CVD events (HR: 1.20, 95% CI 1.02 to 1.42, p=0.03). CONCLUSION: PAT is independently associated with markers of subclinical CVD and incident CVD events. Respiratory-related PAT response is a novel and promising polysomnography metric with cardiovascular implications.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Doença da Artéria Coronariana , Idoso , Aterosclerose/diagnóstico , Doenças Cardiovasculares/diagnóstico , Estudos Transversais , Feminino , Humanos , Estudos Prospectivos , Fatores de Risco , Sono
12.
Phys Rev Lett ; 126(7): 071801, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33666471

RESUMO

The MoEDAL trapping detector consists of approximately 800 kg of aluminum volumes. It was exposed during run 2 of the LHC program to 6.46 fb^{-1} of 13 TeV proton-proton collisions at the LHCb interaction point. Evidence for dyons (particles with electric and magnetic charge) captured in the trapping detector was sought by passing the aluminum volumes comprising the detector through a superconducting quantum interference device (SQUID) magnetometer. The presence of a trapped dyon would be signaled by a persistent current induced in the SQUID magnetometer. On the basis of a Drell-Yan production model, we exclude dyons with a magnetic charge ranging up to five Dirac charges (5g_{D}) and an electric charge up to 200 times the fundamental electric charge for mass limits in the range 870-3120 GeV and also monopoles with magnetic charge up to and including 5g_{D} with mass limits in the range 870-2040 GeV.

13.
Proc Biol Sci ; 287(1929): 20200562, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32546097

RESUMO

Many microbial symbionts have multiple phenotypic consequences for their animal hosts. However, the ways in which different symbiont-mediated phenotypes combine to affect fitness are not well understood. We investigated whether there are correlations between different symbiont-mediated phenotypes. We used the symbiont Spiroplasma, a striking example of a bacterial symbiont conferring diverse phenotypes on insect hosts. We took 11 strains of Spiroplasma infecting pea aphids (Acyrthosiphon pisum) and assessed their ability to provide protection against the fungal pathogen Pandora neoaphidis and the parasitoids Aphidius ervi and Praon volucre. We also assessed effects on male offspring production for five of the Spiroplasma strains. All but one of the Spiroplasma strains provided very strong protection against the parasitoid P. volucre. As previously reported, variable protection against P. neoaphidis and A. ervi was also present; male-killing was likewise a variable phenotype. We find no evidence of any correlation, positive or negative, between the different phenotypes, nor was there any evidence of an effect of symbiont phylogeny on protective phenotype. We conclude that multiple symbiont-mediated phenotypes can evolve independently from one another without trade-offs between them.


Assuntos
Afídeos/microbiologia , Spiroplasma/fisiologia , Animais , Evolução Biológica , Fenótipo , Simbiose
14.
Phys Rev Lett ; 123(2): 021802, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31386510

RESUMO

MoEDAL is designed to identify new physics in the form of stable or pseudostable highly ionizing particles produced in high-energy Large Hadron Collider (LHC) collisions. Here we update our previous search for magnetic monopoles in Run 2 using the full trapping detector with almost four times more material and almost twice more integrated luminosity. For the first time at the LHC, the data were interpreted in terms of photon-fusion monopole direct production in addition to the Drell-Yan-like mechanism. The MoEDAL trapping detector, consisting of 794 kg of aluminum samples installed in the forward and lateral regions, was exposed to 4.0 fb^{-1} of 13 TeV proton-proton collisions at the LHCb interaction point and analyzed by searching for induced persistent currents after passage through a superconducting magnetometer. Magnetic charges equal to or above the Dirac charge are excluded in all samples. Monopole spins 0, ½, and 1 are considered and both velocity-independent and-dependent couplings are assumed. This search provides the best current laboratory constraints for monopoles with magnetic charges ranging from two to five times the Dirac charge.

15.
J Hered ; 110(2): 194-210, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30597046

RESUMO

Next-generation sequencing (NGS) and expression technologies were utilized to investigate the genes and sequence elements in a 586 kb region of chicken chromosome 1 associated with the autosomal recessive diplopodia-1 (dp-1) mutation. This mutation shows a syndromic phenotype similar to known human developmental abnormalities (e.g., cleft palate, polydactyly, omphalocele [exposed viscera]). Toward our goal to ascertain the variant responsible, the entire 586 kb region was sequenced following utilization of a specifically designed capture array and to confirm/validate fine-mapping results. Bioinformatic analyses identified a total of 6142 sequence variants, which included SNPs, indels, and gaps. Of these, 778 SNPs, 146 micro-indels, and 581 gaps were unique to the UCD-Dp-1.003 inbred congenic line; those found within exons and splice sites were studied for contribution to the mutant phenotype. Upon further validation with additional mutant samples, a smaller subset (of variants [51]) remains linked to the mutation. Additionally, utilization of specific samples in the NGS technology was advantageous in that fine-mapping methodologies eliminated an additional 326 kb of sequence information on chromosome 1. Predicted and confirmed protein-coding genes within the smaller 260 kb region were assessed for their developmental expression patterns over several stages of early embryogenesis in regions/tissues of interest (e.g., digits, craniofacial region). Based on these results and known function in other vertebrates, 2 genes within 5 kb of each other, MRE11 and GPR83, are proposed as high-priority candidates for the dp-1 mutation.


Assuntos
Galinhas/genética , Anormalidades Craniofaciais/genética , Deformidades Congênitas dos Membros/genética , Proteína Homóloga a MRE11/genética , Receptores Acoplados a Proteínas G/genética , Animais , Mapeamento Cromossômico , Anormalidades Craniofaciais/diagnóstico , Análise Mutacional de DNA , Sequenciamento de Nucleotídeos em Larga Escala , Deformidades Congênitas dos Membros/diagnóstico , Mutação , Síndrome
16.
J Appl Microbiol ; 125(5): 1482-1493, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29939449

RESUMO

AIMS: The aim of this study was to optimize the potential of Beauveria bassiana through cell electrofusion technique with emphasis on improving its thermotolerance and virulence against western flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae) (WFT). METHODS AND RESULTS: Nine B. bassiana isolates were tested against western flower thrips, F. occidentalis (Thysanoptera: Thripidae) (WFT) to estimate their pathogenicity and speed of infection under laboratory conditions. The isolates were also exposed to 25, 36, 38 and 40°C, for 24, 48, 72 and 120 h. Two isolates with the highest virulence against WFT and highest thermotolerance were selected and paired using a cell electrofusion technique to obtain a single strain that was both highly virulent and thermotolerant. To determine the hybrid conidia among the fusion cells, each selected isolate was loaded with a different nuclei-staining fluorescent dye before the fusion process. Hybridized fungal strains were acquired by a series of sequential dilutions and were tested for thermotolerance and virulence against WFT. Those that demonstrated both characteristics (high thermotolerance and virulence) similar to or greater than the parental isolates were considered hybrids. CONCLUSIONS: The results demonstrated that genetic transformation using cell electrofusion can be used to obtain hybrid isolates of fungal pathogens that contain the desired genes from selected isolates. Further DNA-based analysis is required to determine the genetic variation between hybrids and the parental isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to demonstrate genetic transformation in B. bassiana by use of cell electrofusion and it could be developed to create superior hybrid isolates with various desired properties for integrated pest management and industrial uses in the future.


Assuntos
Beauveria/genética , Termotolerância/genética , Animais , Beauveria/patogenicidade , Beauveria/fisiologia , Controle Biológico de Vetores/métodos , Tisanópteros , Transformação Genética , Virulência
17.
J Phys Chem A ; 122(9): 2329-2343, 2018 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-29442510

RESUMO

(D3-)Methanol-nitrogen monoxide (CH3OH/CD3OH-NO) ices were exposed to ionizing radiation to facilitate the eventual determination of the CH3NO2 potential energy surface (PES) in the condensed phase. Reaction intermediates and products were monitored via infrared spectroscopy (FTIR) and photoionization reflectron time-of-flight mass spectrometry (PI-ReTOF-MS) during the irradiation and temperature controlled desorption (TPD) phase, respectively. Distinct photoionization energies were utilized to discriminate the isomer(s) formed in these processes. The primary methanol radiolysis products were the methoxy (CH3O) and hydroxymethyl (CH2OH) radicals along with atomic hydrogen. The former was found to react barrierlessly with nitrogen monoxide resulting in the formation of cis- and trans-methyl nitrite (CH3ONO), which is the most abundant product that can be observed in the irradiated samples. On the other hand, the self-recombination of hydroxymethyl radicals yielding ethylene glycol (HO(CH2)2OH) and glycerol (HOCH2CH2(OH)CH2OH) is preferred over the recombination with nitrogen monoxide to nitrosomethanol (HOCH2NO).

18.
Biochim Biophys Acta ; 1859(5): 744-56, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27032571

RESUMO

miRNAs play critical roles in heart disease. In addition to differential miRNA expression, miRNA-mediated control is also affected by variable miRNA processing or alternative 3'-end cleavage and polyadenylation (APA) of their mRNA targets. To what extent these phenomena play a role in the heart remains unclear. We sought to explore miRNA processing and mRNA APA in cardiomyocytes, and whether these change during cardiac hypertrophy. Thoracic aortic constriction (TAC) was performed to induce hypertrophy in C57BL/6J mice. RNA extracted from cardiomyocytes of sham-treated, pre-hypertrophic (2 days post-TAC), and hypertrophic (7 days post-TAC) mice was subjected to small RNA- and poly(A)-test sequencing (PAT-Seq). Differential expression analysis matched expectations; nevertheless we identified ~400 mRNAs and hundreds of noncoding RNA loci as altered with hypertrophy for the first time. Although multiple processing variants were observed for many miRNAs, there was little change in their relative proportions during hypertrophy. PAT-Seq mapped ~48,000 mRNA 3'-ends, identifying novel 3' untranslated regions (3'UTRs) for over 7000 genes. Importantly, hypertrophy was associated with marked changes in APA with a net shift from distal to more proximal mRNA 3'-ends, which is predicted to decrease overall miRNA repression strength. We independently validated several examples of 3'UTR proportion change and showed that alternative 3'UTRs associate with differences in mRNA translation. Our work suggests that APA contributes to altered gene expression with the development of cardiomyocyte hypertrophy and provides a rich resource for a systems-level understanding of miRNA-mediated regulation in physiological and pathological states of the heart.


Assuntos
Hipertrofia/genética , MicroRNAs/genética , Miócitos Cardíacos/metabolismo , Biossíntese de Proteínas/genética , Animais , Regulação da Expressão Gênica , Humanos , Camundongos , MicroRNAs/metabolismo , Miócitos Cardíacos/patologia , Poliadenilação/genética , Processamento Pós-Transcricional do RNA
19.
Am J Transplant ; 17(5): 1193-1203, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27888551

RESUMO

Costimulation blockade (CoB) via belatacept is a lower-morbidity alternative to calcineurin inhibitor (CNI)-based immunosuppression. However, it has higher rates of early acute rejection. These early rejections are mediated in part by memory T cells, which have reduced dependence on the pathway targeted by belatacept and increased adhesion molecule expression. One such molecule is leukocyte function antigen (LFA)-1. LFA-1 exists in two forms: a commonly expressed, low-affinity form and a transient, high-affinity form, expressed only during activation. We have shown that antibodies reactive with LFA-1 regardless of its configuration are effective in eliminating memory T cells but at the cost of impaired protective immunity. Here we test two novel agents, leukotoxin A and AL-579, each of which targets the high-affinity form of LFA-1, to determine whether this more precise targeting prevents belatacept-resistant rejection. Despite evidence of ex vivo and in vivo ligand-specific activity, neither agent when combined with belatacept proved superior to belatacept monotherapy. Leukotoxin A approached a ceiling of toxicity before efficacy, while AL-579 failed to significantly alter the peripheral immune response. These data, and prior studies, suggest that LFA-1 blockade may not be a suitable adjuvant agent for CoB-resistant rejection.


Assuntos
Abatacepte/farmacologia , Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto/imunologia , Memória Imunológica/imunologia , Transplante de Rim/efeitos adversos , Antígeno-1 Associado à Função Linfocitária/química , Linfócitos T/imunologia , Animais , Modelos Animais de Doenças , Taxa de Filtração Glomerular , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/efeitos dos fármacos , Memória Imunológica/efeitos dos fármacos , Imunossupressores/farmacologia , Testes de Função Renal , Antígeno-1 Associado à Função Linfocitária/metabolismo , Macaca mulatta , Complicações Pós-Operatórias , Linfócitos T/efeitos dos fármacos , Linfócitos T/patologia
20.
Breast Cancer Res Treat ; 161(3): 567-574, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28005246

RESUMO

PURPOSE: Endoxifen concentrations have been associated with breast cancer recurrence in tamoxifen-treated patients. However, tamoxifen itself and other metabolites also show antiestrogenic anti-tumor activity. Therefore, the aim of this study was to develop a comprehensive Antiestrogenic Activity Score (AAS), which accounts for concentration and antiestrogenic activity of tamoxifen and three metabolites. An association between the AAS and recurrence-free survival was investigated and compared to a previously published threshold for endoxifen concentrations of 5.97 ng/mL. PATIENTS AND METHODS: The antiestrogenic activities of tamoxifen, (Z)-endoxifen, (Z)-4-hydroxytamoxifen, and N-desmethyltamoxifen were determined in a cell proliferation assay. The AAS was determined by calculating the sum of each metabolite concentration multiplied by an IC50 ratio, relative to tamoxifen. The AAS was calculated for 1370 patients with estrogen receptor alpha (ERα)-positive breast cancer. An association between AAS and recurrence was investigated using Cox regression and compared with the 5.97 ng/mL endoxifen threshold using concordance indices. RESULTS: An AAS threshold of 1798 was associated with recurrence-free survival, hazard ratio (HR) 0.67 (95% confidence interval (CI) 0.47-0.96), bias corrected after bootstrap HR 0.69 (95% CI 0.48-0.99). The concordance indices for AAS and endoxifen did not significantly differ; however, using the AAS threshold instead of endoxifen led to different dose recommendations for 5.2% of the patients. CONCLUSIONS: Endoxifen concentrations can serve as a proxy for the antiestrogenic effect of tamoxifen and metabolites. However, for the aggregate effect of tamoxifen and three metabolites, defined by an integrative algorithm, a trend towards improving treatment is seen and moreover, is significantly associated with breast cancer recurrence.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Antagonistas de Estrogênios/farmacologia , Tamoxifeno/farmacologia , Antineoplásicos Hormonais/metabolismo , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/epidemiologia , Relação Dose-Resposta a Droga , Antagonistas de Estrogênios/metabolismo , Antagonistas de Estrogênios/uso terapêutico , Feminino , Humanos , Concentração Inibidora 50 , Estimativa de Kaplan-Meier , Prognóstico , Modelos de Riscos Proporcionais , Tamoxifeno/metabolismo , Tamoxifeno/uso terapêutico , Resultado do Tratamento
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