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1.
Nature ; 583(7814): 39-42, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612222

RESUMO

The interiors of giant planets remain poorly understood. Even for the planets in the Solar System, difficulties in observation lead to large uncertainties in the properties of planetary cores. Exoplanets that have undergone rare evolutionary processes provide a route to understanding planetary interiors. Planets found in and near the typically barren hot-Neptune 'desert'1,2 (a region in mass-radius space that contains few planets) have proved to be particularly valuable in this regard. These planets include HD149026b3, which is thought to have an unusually massive core, and recent discoveries such as LTT9779b4 and NGTS-4b5, on which photoevaporation has removed a substantial part of their outer atmospheres. Here we report observations of the planet TOI-849b, which has a radius smaller than Neptune's but an anomalously large mass of [Formula: see text] Earth masses and a density of [Formula: see text] grams per cubic centimetre, similar to Earth's. Interior-structure models suggest that any gaseous envelope of pure hydrogen and helium consists of no more than [Formula: see text] per cent of the total planetary mass. The planet could have been a gas giant before undergoing extreme mass loss via thermal self-disruption or giant planet collisions, or it could have avoided substantial gas accretion, perhaps through gap opening or late formation6. Although photoevaporation rates cannot account for the mass loss required to reduce a Jupiter-like gas giant, they can remove a small (a few Earth masses) hydrogen and helium envelope on timescales of several billion years, implying that any remaining atmosphere on TOI-849b is likely to be enriched by water or other volatiles from the planetary interior. We conclude that TOI-849b is the remnant core of a giant planet.

2.
Ann Pharmacother ; 58(5): 480-493, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37589369

RESUMO

BACKGROUND: Bacterial vaginosis (BV) is a highly prevalent vaginal infection. OBJECTIVES: Primary objectives of this study were to examine treatment patterns among female patients with Medicaid coverage who were diagnosed with incident BV, the frequency of BV-associated complications, and health care resource utilization (HCRU) and associated costs of incident BV and its recurrence. Secondary objectives were to identify predictors of total all-cause health care costs and number of treatment courses. METHODS: Female patients aged 12-49 years with an incident vaginitis diagnosis and ≥1 pharmacy claim for a BV medication were selected from the Merative MarketScan Medicaid database (2017-2020). Additional treatment courses were evaluated during a ≥12-month follow-up period, in which new cases of BV-associated complications and HCRU and the associated costs were also measured. Generalized linear models were used to identify baseline predictors of total all-cause health care costs and number of treatment courses. RESULTS: An incident vaginitis diagnosis and ≥1 BV medication claim were present in 114 313 patients (mean age: 28.4 years; 48.6% black). During the follow-up, 56.6% had 1 treatment course, 24.9% had 2, 10.2% had 3, and 8.3% had ≥4; 43.4% had BV recurrence. Oral metronidazole (88.5%) was the most frequently prescribed medication. Nearly 1 in 5 had a new occurrence of a BV-associated complication; most (76.6%) were sexually transmitted infections (STIs). Total all-cause and BV-related costs averaged $5794 and $300, respectively, per patient; both increased among those with more treatment courses. Older age, pregnancy, comorbidity, any STIs, postprocedural gynecological infection (PGI), and infertility were predictive of higher total all-cause health care costs, while race/ethnicity other than white was predictive of lower costs. Older age, black race, any STIs, pelvic inflammatory disease, and PGI were predictive of >1 treatment courses. CONCLUSION AND RELEVANCE: The high recurrence of BV represents an unmet need in women's health care and better treatments are necessary.


Assuntos
Infecções Sexualmente Transmissíveis , Vaginite , Vaginose Bacteriana , Gravidez , Feminino , Humanos , Estados Unidos/epidemiologia , Adulto , Vaginose Bacteriana/tratamento farmacológico , Vaginose Bacteriana/epidemiologia , Vaginose Bacteriana/microbiologia , Medicaid , Estresse Financeiro , Custos de Cuidados de Saúde
3.
Ann Intern Med ; 176(4): 496-504, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37011399

RESUMO

BACKGROUND: Treatment guidelines and U.S. Food and Drug Administration emergency use authorizations (EUAs) of monoclonal antibodies (mAbs) for treatment of high-risk outpatients with mild to moderate COVID-19 changed frequently as different SARS-CoV-2 variants emerged. OBJECTIVE: To evaluate whether early outpatient treatment with mAbs, overall and by mAb product, presumed SARS-CoV-2 variant, and immunocompromised status, is associated with reduced risk for hospitalization or death at 28 days. DESIGN: Hypothetical pragmatic randomized trial from observational data comparing mAb-treated patients with a propensity score-matched, nontreated control group. SETTING: Large U.S. health care system. PARTICIPANTS: High-risk outpatients eligible for mAb treatment under any EUA with a positive SARS-CoV-2 test result from 8 December 2020 to 31 August 2022. INTERVENTION: Single-dose intravenous mAb treatment with bamlanivimab, bamlanivimab-etesevimab, sotrovimab, bebtelovimab, or intravenous or subcutaneous casirivimab-imdevimab administered within 2 days of a positive SARS-CoV-2 test result. MEASUREMENTS: The primary outcome was hospitalization or death at 28 days among treated patients versus a nontreated control group (no treatment or treatment ≥3 days after SARS-CoV-2 test date). RESULTS: The risk for hospitalization or death at 28 days was 4.6% in 2571 treated patients and 7.6% in 5135 nontreated control patients (risk ratio [RR], 0.61 [95% CI, 0.50 to 0.74]). In sensitivity analyses, the corresponding RRs for 1- and 3-day treatment grace periods were 0.59 and 0.49, respectively. In subgroup analyses, those receiving mAbs when the Alpha and Delta variants were presumed to be predominant had estimated RRs of 0.55 and 0.53, respectively, compared with 0.71 for the Omicron variant period. Relative risk estimates for individual mAb products all suggested lower risk for hospitalization or death. Among immunocompromised patients, the RR was 0.45 (CI, 0.28 to 0.71). LIMITATIONS: Observational study design, SARS-CoV-2 variant presumed by date rather than genotyping, no data on symptom severity, and partial data on vaccination status. CONCLUSION: Early mAb treatment among outpatients with COVID-19 is associated with lower risk for hospitalization or death for various mAb products and SARS-CoV-2 variants. PRIMARY FUNDING SOURCE: None.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Estudos de Coortes , Anticorpos Monoclonais/uso terapêutico
4.
J Infect Dis ; 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37972260

RESUMO

BACKGROUND: Improved COVID-19 prevention is needed for immunocompromised individuals. METHODS: Prospective study of healthcare workers (HCW) and immunocompromised participants with baseline serology following 2 mRNA vaccines and who were retested after dose 3 (D3); multivariable regression was used to identify predictors of serological responses. IFNγ/TNFα T-cell responses were assessed in a subset. RESULTS: 536 participants were included: 492 immunocompromised [(206 solid organ transplant (SOT), 128 autoimmune, 80 hematologic malignancy (HM), 48 solid tumor, 25 HIV], 44 HCW. D3 significantly increased Spike IgG levels among all, but SOT and HM participants had the lowest median antibody levels post-D3 (increase from 0.09 to 0.83 and 0.27 to 1.92, respectively), versus HCW and persons with HIV, autoimmune conditions, and solid tumors (increases from 4.44 to 19.79, 2.9 to 15.75, 3.82 to 16.32, and 4.1 to 25.54, respectively). Seropositivity post-D3 was lowest for SOT (49.0%) and HM (57.8%), versus others (>90% seropositive). Neutralization post-D3 was lowest among SOT and HM. Predictors of lower antibody levels included low baseline levels and shorter intervals between vaccines. T-cell responses against Spike increased significantly among HCW and non-significantly among immunocompromised individuals. CONCLUSIONS: D3 significantly improves serological but not T-cell responses among immunocompromised individuals. SOT and HM patients have suboptimal responses to D3.

5.
J Neurosci ; 41(16): 3635-3650, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33687965

RESUMO

Successful execution of behavior requires coordinated activity and communication between multiple cell types. Studies using the relatively simple neural circuits of invertebrates have helped to uncover how conserved molecular and cellular signaling events shape animal behavior. To understand the mechanisms underlying neural circuit activity and behavior, we have been studying a simple circuit that drives egg-laying behavior in the nematode worm Caenorhabditis elegans Here we show that the sex-specific, ventral C (VC) motor neurons are important for vulval muscle contractility and egg laying in response to serotonin. Ca2+ imaging experiments show the VCs are active during times of vulval muscle contraction and vulval opening, and optogenetic stimulation of the VCs promotes vulval muscle Ca2+ activity. Blocking VC neurotransmission inhibits egg laying in response to serotonin and increases the failure rate of egg-laying attempts, indicating that VC signaling facilitates full vulval muscle contraction and opening of the vulva for efficient egg laying. We also find the VCs are mechanically activated in response to vulval opening. Optogenetic stimulation of the vulval muscles is sufficient to drive VC Ca2+ activity and requires muscle contractility, showing the presynaptic VCs and the postsynaptic vulval muscles can mutually excite each other. Together, our results demonstrate that the VC neurons facilitate efficient execution of egg-laying behavior by coordinating postsynaptic muscle contractility in response to serotonin and mechanosensory feedback.SIGNIFICANCE STATEMENT Many animal motor behaviors are modulated by the neurotransmitters, serotonin and ACh. Such motor circuits also respond to mechanosensory feedback, but how neurotransmitters and mechanoreceptors work together to coordinate behavior is not well understood. We address these questions using the egg-laying circuit in Caenorhabditis elegans where we can manipulate presynaptic neuron and postsynaptic muscle activity in behaving animals while recording circuit responses through Ca2+ imaging. We find that the cholinergic VC motoneurons are important for proper vulval muscle contractility and egg laying in response to serotonin. Muscle contraction also activates the VCs, forming a positive feedback loop that promotes full contraction for egg release. In all, mechanosensory feedback provides a parallel form of modulation that shapes circuit responses to neurotransmitters.


Assuntos
Caenorhabditis elegans/fisiologia , Neurônios Motores/fisiologia , Oviposição/fisiologia , Serotonina/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Sinalização do Cálcio/fisiologia , Feminino , Genes Reporter/genética , Masculino , Contração Muscular/efeitos dos fármacos , Músculos/inervação , Músculos/fisiologia , Optogenética , Receptores Pré-Sinápticos/fisiologia , Transmissão Sináptica/fisiologia , Vulva/fisiologia
6.
Clin Infect Dis ; 75(1): e630-e644, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35179197

RESUMO

BACKGROUND: We studied humoral responses after coronavirus disease 2019 (COVID-19) vaccination across varying causes of immunodeficiency. METHODS: Prospective study of fully vaccinated immunocompromised adults (solid organ transplant [SOT], hematologic malignancy, solid cancers, autoimmune conditions, human immunodeficiency virus [HIV]) versus nonimmunocompromised healthcare workers (HCWs). The primary outcome was the proportion with a reactive test (seropositive) for immunoglobulin G to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor-binding domain. Secondary outcomes were comparisons of antibody levels and their correlation with pseudovirus neutralization titers. Stepwise logistic regression was used to identify factors associated with seropositivity. RESULTS: A total of 1271 participants enrolled: 1099 immunocompromised and 172 HCW. Compared with HCW (92.4% seropositive), seropositivity was lower among participants with SOT (30.7%), hematological malignancies (50.0%), autoimmune conditions (79.1%), solid tumors (78.7%), and HIV (79.8%) (P < .01). Factors associated with poor seropositivity included age, greater immunosuppression, time since vaccination, anti-CD20 monoclonal antibodies, and vaccination with BNT162b2 (Pfizer) or adenovirus vector vaccines versus messenger RNA (mRNA)-1273 (Moderna). mRNA-1273 was associated with higher antibody levels than BNT162b2 or adenovirus vector vaccines after adjusting for time since vaccination, age, and underlying condition. Antibody levels were strongly correlated with pseudovirus neutralization titers (Spearman r = 0.89, P < .0001), but in seropositive participants with intermediate antibody levels, neutralization titers were significantly lower in immunocompromised individuals versus HCW. CONCLUSIONS: Antibody responses to COVID-19 vaccines were lowest among SOT and anti-CD20 monoclonal recipients, and recipients of vaccines other than mRNA-1273. Among those with intermediate antibody levels, pseudovirus neutralization titers were lower in immunocompromised patients than HCWs. Additional SARS-CoV-2 preventive approaches are needed for immunocompromised persons, which may need to be tailored to the cause of immunodeficiency.


Assuntos
COVID-19 , Infecções por HIV , Adulto , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Infecções por HIV/complicações , Humanos , Hospedeiro Imunocomprometido , Estudos Prospectivos , SARS-CoV-2 , Vacinação
7.
Ecol Lett ; 25(2): 366-377, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34818698

RESUMO

Understanding mechanisms of coexistence is a central topic in ecology. Mathematical analysis of models of competition between two identical species moving at different rates of symmetric diffusion in heterogeneous environments show that the slower mover excludes the faster one. The models have not been tested empirically and lack inclusions of a component of directed movement toward favourable areas. To address these gaps, we extended previous theory by explicitly including exploitable resource dynamics and directed movement. We tested the mathematical results experimentally using laboratory populations of the nematode worm, Caenorhabditis elegans. Our results not only support the previous theory that the species diffusing at a slower rate prevails in heterogeneous environments but also reveal that moderate levels of a directed movement component on top of the diffusive movement allow species to coexist. Our results broaden the theory of species coexistence in heterogeneous space and provide empirical confirmation of the mathematical predictions.


Assuntos
Distribuição Animal , Ecologia , Ecossistema , Animais , Modelos Biológicos , Dinâmica Populacional
8.
PLoS Genet ; 15(1): e1007896, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30677018

RESUMO

Neurons typically release both a small-molecule neurotransmitter and one or more neuropeptides, but how these two types of signal from the same neuron might act together remains largely obscure. For example, serotonergic neurons in mammalian brain express the neuropeptide Substance P, but it is unclear how this co-released neuropeptide might modulate serotonin signaling. We studied this issue in C. elegans, in which all serotonergic neurons express the neuropeptide NLP-3. The serotonergic Hermaphrodite Specific Neurons (HSNs) are command motor neurons within the egg-laying circuit which have been shown to release serotonin to initiate egg-laying behavior. We found that egg-laying defects in animals lacking serotonin were far milder than in animals lacking HSNs, suggesting that HSNs must release other signal(s) in addition to serotonin to stimulate egg laying. While null mutants for nlp-3 had only mild egg-laying defects, animals lacking both serotonin and NLP-3 had severe defects, similar to those of animals lacking HSNs. Optogenetic activation of HSNs induced egg laying in wild-type animals, and in mutant animals lacking either serotonin or NLP-3, but failed to induce egg laying in animals lacking both. We recorded calcium activity in the egg-laying muscles of animals lacking either serotonin, NLP-3, or both. The single mutants, and to a greater extent the double mutant, showed muscle activity that was uncoordinated and unable to expel eggs. Specifically, the vm2 muscles cells, which are direct postsynaptic targets of the HSN, failed to contract simultaneously with other egg-laying muscle cells. Our results show that the HSN neurons use serotonin and the neuropeptide NLP-3 as partially redundant co-transmitters that together stimulate and coordinate activity of the target cells onto which they are released.


Assuntos
Comportamento Animal , Neuropeptídeos/genética , Oviposição/genética , Serotonina/genética , Acetilcolina/genética , Acetilcolina/metabolismo , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiologia , Transtornos do Desenvolvimento Sexual/genética , Feminino , Masculino , Neurônios Motores/metabolismo , Mutação , Neurotransmissores/genética , Neurônios Serotoninérgicos/metabolismo , Transdução de Sinais
9.
PLoS Genet ; 13(4): e1006697, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28384151

RESUMO

Animal behaviors are often composed of distinct alternating behavioral states. Neuromodulatory signals are thought to be critical for establishing stable behavioral states and for orchestrating transitions between them. However, we have only a limited understanding of how neuromodulatory systems act in vivo to alter circuit performance and shape behavior. To address these questions, we have investigated neuromodulatory signaling in the context of Caenorhabditis elegans egg-laying. Egg-laying activity cycles between discrete states-short bursts of egg deposition (active phases) that alternate with prolonged quiescent periods (inactive phases). Here using genetic, pharmacological and optogenetic approaches for cell-specific activation and inhibition, we show that a group of neurosecretory cells (uv1) located in close spatial proximity to the egg-laying neuromusculature direct the temporal organization of egg-laying by prolonging the duration of inactive phases. We demonstrate that the modulatory effects of the uv1 cells are mediated by peptides encoded by the nlp-7 and flp-11 genes that act locally to inhibit circuit activity, primarily by inhibiting vesicular release of serotonin from HSN motor neurons. This peptidergic inhibition is achieved, at least in part, by reducing synaptic vesicle abundance in the HSN motor neurons. By linking the in vivo actions of specific neuropeptide signaling systems with the generation of stable behavioral outcomes, our study reveals how cycles of neuromodulation emanating from non-neuronal cells can fundamentally shape the organization of a behavioral program.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Neuropeptídeos/genética , Oviposição/genética , Acetilcolina/metabolismo , Animais , Comportamento Animal , Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiologia , Neurônios Motores/metabolismo , Neuropeptídeos/metabolismo , Neurossecreção/genética , Neurônios Serotoninérgicos/metabolismo , Serotonina/metabolismo , Transdução de Sinais/genética
10.
J Neurosci ; 38(28): 6283-6298, 2018 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-29891728

RESUMO

Neuron activity accompanies synapse formation and maintenance, but how early circuit activity contributes to behavior development is not well understood. Here, we use the Caenorhabditis elegans egg-laying motor circuit as a model to understand how coordinated cell and circuit activity develops and drives a robust two-state behavior in adults. Using calcium imaging in behaving animals, we find the serotonergic hermaphrodite-specific neurons (HSNs) and vulval muscles show rhythmic calcium transients in L4 larvae before eggs are produced. HSN activity in L4 is tonic and lacks the alternating burst-firing/quiescent pattern seen in egg-laying adults. Vulval muscle activity in L4 is initially uncoordinated but becomes synchronous as the anterior and posterior muscle arms meet at HSN synaptic release sites. However, coordinated muscle activity does not require presynaptic HSN input. Using reversible silencing experiments, we show that neuronal and vulval muscle activity in L4 is not required for the onset of adult behavior. Instead, the accumulation of eggs in the adult uterus renders the muscles sensitive to HSN input. Sterilization or acute electrical silencing of the vulval muscles inhibits presynaptic HSN activity and reversal of muscle silencing triggers a homeostatic increase in HSN activity and egg release that maintains ∼12-15 eggs in the uterus. Feedback of egg accumulation depends upon the vulval muscle postsynaptic terminus, suggesting that a retrograde signal sustains HSN synaptic activity and egg release. Our results show that egg-laying behavior in C. elegans is driven by a homeostat that scales serotonin motor neuron activity in response to postsynaptic muscle feedback.SIGNIFICANCE STATEMENT The functional importance of early, spontaneous neuron activity in synapse and circuit development is not well understood. Here, we show in the nematode Caenorhabditis elegans that the serotonergic hermaphrodite-specific neurons (HSNs) and postsynaptic vulval muscles show activity during circuit development, well before the onset of adult behavior. Surprisingly, early activity is not required for circuit development or the onset of adult behavior and the circuit remains unable to drive egg laying until fertilized embryos are deposited into the uterus. Egg accumulation potentiates vulval muscle excitability, but ultimately acts to promote burst firing in the presynaptic HSNs which results in egg laying. Our results suggest that mechanosensory feedback acts at three distinct steps to initiate, sustain, and terminate C. elegans egg-laying circuit activity and behavior.


Assuntos
Caenorhabditis elegans/fisiologia , Larva/fisiologia , Músculo Esquelético/fisiologia , Oviposição/fisiologia , Neurônios Serotoninérgicos/fisiologia , Animais , Retroalimentação , Feminino , Homeostase/fisiologia , Neurogênese/fisiologia , Vulva/fisiologia
11.
J Am Chem Soc ; 140(13): 4485-4488, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29561604

RESUMO

A photochemical strategy to encode fluorescence signals in vivo with spatial control was designed around the unique properties of a photoactivatable borondipyrromethene (BODIPY). The photoinduced disconnection of two oxazines, flanking a single BODIPY, in two consecutive steps produces a mixture of three emissive molecules with resolved fluorescence inside polymer beads. The relative amounts and emission intensities of the three fluorophores can be regulated precisely in each bead by adjusting the dose of activating photons to mark individual particles with distinct codes of fluorescence signals. The visible wavelengths and mild illumination sufficient to induce these transformations permit the photochemical barcoding of beads also in living nematodes. Different regions of the same animal can be labeled with distinct barcodes to allow the monitoring of their dynamics for long times with no toxic effects. Thus, our photochemical strategy for the generation of fluorescence barcodes can produce multiple and distinguishable labels in the same biological sample to enable the spatiotemporal tracking of, otherwise indistinguishable, targets.


Assuntos
Compostos de Boro/química , Código de Barras de DNA Taxonômico , Luz , Oxiquinolina/química
12.
Psychosom Med ; 80(5): 483-491, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29621045

RESUMO

OBJECTIVE: The aims of this study were to examine the potential association between sleep problems, symptom burden, and survival in patients with advanced cancer. METHODS: A prospective study of 294 patients with gastrointestinal cancer administered questionnaires assessing sleep, depression, anxiety, stress, pain, fatigue, and health-related quality of life. Serum levels of cytokines including interleukin (IL)-1α, IL-1ß, tumor necrosis factor α, IL-10, IL-2, and interferon-γ were measured to assess biological mediation between sleep and survival. Survival was measured as time from diagnosis to death. RESULTS: Fifty-nine percent of patients reported poor sleep quality, 53% reported poor sleep efficiency, 39% reported sleep latency greater than 30 minutes, and 45% reported sleeping less than 6 hours or greater than 10 hours. We found a significant association between sleep duration and symptom burden. Shorter sleep duration was significantly associated with higher levels of fatigue (r = -0.169, p = .01), pain (r = -0.302, p = .01), anxiety (r = -0.182, p = .01), depression (r = -0.172, p = .003), and lower levels of quality of life (r = 0.240, p = .01). After adjustment for demographic, psychological, and disease-specific factors, short sleep duration was associated with reduced survival (hazard ratio [HR] linear = 0.485, 95% confidence interval = 0.275-0.857) and there was also evidence for a quadratic pattern (HR quadrati = 1.064, 95% confidence interval = 1.015-1.115) suggesting a curvilinear relationship between sleep duration and survival. Interleukin 2 was the only cytokine significantly related to survival (HR = 1.01, p = .003) and sleep duration (ß = -30.11, p = .027). When of IL-2 was added to the multivariable model, short and long sleep (ß = -0.557, p = .097; ß = 0.046, p = .114) were no longer significantly related to survival, suggesting mediation by IL-2. CONCLUSION: Sleep duration was associated with symptom burden and poorer survival and IL-2 was found to mediate the association between sleep and survival. Screening and treatment of sleep problems in patients diagnosed with cancer are warranted.


Assuntos
Citocinas/sangue , Neoplasias Gastrointestinais , Transtornos do Sono-Vigília , Idoso , Feminino , Neoplasias Gastrointestinais/sangue , Neoplasias Gastrointestinais/complicações , Neoplasias Gastrointestinais/mortalidade , Neoplasias Gastrointestinais/fisiopatologia , Humanos , Interleucina-2/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Transtornos do Sono-Vigília/sangue , Transtornos do Sono-Vigília/fisiopatologia
13.
Bioconjug Chem ; 28(5): 1519-1528, 2017 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-28430413

RESUMO

Seven macromolecular constructs incorporating multiple borondipyrromethene (BODIPY) fluorophores along a common poly(methacrylate) backbone with decyl and oligo(ethylene glycol) side chains were synthesized. The hydrophilic oligo(ethylene glycol) components impose solubility in aqueous environment on the overall assembly. The hydrophobic decyl chains effectively insulate the fluorophores from each other to prevent detrimental interchromophoric interactions and preserve their photophysical properties. As a result, the brightness of these multicomponent assemblies is approximately three times greater than that of a model BODIPY monomer. Such a high brightness level is maintained even after injection of the macromolecular probes in living nematodes, allowing their visualization with a significant improvement in signal-to-noise ratio, relative to the model monomer, and no cytotoxic or behavioral effects. The covalent scaffold of these macromolecular constructs also permits their subsequent conjugation to secondary antibodies. The covalent attachment of polymer and biomolecule does not hinder the targeting ability of the latter and the resulting bioconjugates can be exploited to stain the tubulin structure of model cells to enable their visualization with optimal signal-to-noise ratios. These results demonstrate that this particular structural design for the incorporation of multiple chromophores within the same covalent construct is a viable one to preserve the photophysical properties of the emissive species and enable the assembly of bioimaging probes with enhanced brightness.


Assuntos
Compostos de Boro/química , Caenorhabditis elegans/citologia , Diagnóstico por Imagem/métodos , Corantes Fluorescentes/química , Substâncias Macromoleculares/química , Polímeros/química , Animais , Caenorhabditis elegans/metabolismo , Células HeLa , Humanos , Nanopartículas/química
14.
Health Care Manag (Frederick) ; 34(4): 293-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26506290

RESUMO

A study was conducted to determine the perceptions of chief executive officers in US hospitals regarding the most important characteristics aspiring health care executives should possess. The results of this 2012 study were compared with a previous study conducted in 2007 to determine if the perceptions had changed over time.


Assuntos
Diretores de Hospitais , Atenção à Saúde/organização & administração , Hospitais , Liderança , Competência Profissional , Humanos , Inquéritos e Questionários , Estados Unidos
15.
Health Care Manag (Frederick) ; 34(1): 23-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25627851

RESUMO

A ministudy was conducted to collect self-reported employee turnover rates in US hospitals. The results indicate many hospitals are struggling with high employee turnover rates. Widespread variances in ratings were observed across hospitals, which may be due to lack of consistency in how they each calculate their employee turnover. This makes benchmarking for the purposes of performance improvement challenging.


Assuntos
Hospitais/estatística & dados numéricos , Reorganização de Recursos Humanos/estatística & dados numéricos , Lealdade ao Trabalho , Reorganização de Recursos Humanos/tendências , Estados Unidos
16.
J Neurosci ; 33(2): 761-75, 2013 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-23303953

RESUMO

Caenorhabditis elegans regulates egg laying by alternating between an inactive phase and a serotonin-triggered active phase. We found that the conserved ERG [ether-a-go-go (EAG) related gene] potassium channel UNC-103 enables this two-state behavior by limiting excitability of the egg-laying muscles. Using both high-speed video recording and calcium imaging of egg-laying muscles in behaving animals, we found that the muscles appear to be excited at a particular phase of each locomotor body bend. During the inactive phase, this rhythmic excitation infrequently evokes calcium transients or contraction of the egg-laying muscles. During the serotonin-triggered active phase, however, these muscles are more excitable and each body bend is accompanied by a calcium transient that drives twitching or full contraction of the egg-laying muscles. We found that ERG-null mutants lay eggs too frequently, and that ERG function is necessary and sufficient in the egg-laying muscles to limit egg laying. ERG K(+) channels localize to postsynaptic sites in the egg-laying muscle, and mutants lacking ERG have more frequent calcium transients and contractions of the egg-laying muscles even during the inactive phase. Thus ERG channels set postsynaptic excitability at a threshold so that further adjustments of excitability by serotonin generate two distinct behavioral states.


Assuntos
Comportamento Animal/fisiologia , Caenorhabditis elegans/fisiologia , Canais de Potássio Éter-A-Go-Go/fisiologia , Músculos/inervação , Músculos/fisiologia , Oviposição/fisiologia , Sinapses/fisiologia , Regiões 3' não Traduzidas/genética , Animais , Sinalização do Cálcio/fisiologia , DNA/biossíntese , DNA/genética , Feminino , Microscopia Confocal , Contração Muscular/fisiologia , Domínios PDZ/genética , Reação em Cadeia da Polimerase , Serotonina/fisiologia , Sinapses/ultraestrutura , Transgenes/genética
17.
Epilepsia ; 55(6): 858-65, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24828792

RESUMO

OBJECTIVE: To establish the genetic basis of Landau-Kleffner syndrome (LKS) in a cohort of two discordant monozygotic (MZ) twin pairs and 11 isolated cases. METHODS: We used a multifaceted approach to identify genetic risk factors for LKS. Array comparative genomic hybridization (CGH) was performed using the Agilent 180K array. Whole genome methylation profiling was undertaken in the two discordant twin pairs, three isolated LKS cases, and 12 control samples using the Illumina 27K array. Exome sequencing was undertaken in 13 patients with LKS including two sets of discordant MZ twins. Data were analyzed with respect to novel and rare variants, overlapping genes, variants in reported epilepsy genes, and pathway enrichment. RESULTS: A variant (cG1553A) was found in a single patient in the GRIN2A gene, causing an arginine to histidine change at site 518, a predicted glutamate binding site. Following copy number variation (CNV), methylation, and exome sequencing analysis, no single candidate gene was identified to cause LKS in the remaining cohort. However, a number of interesting additional candidate variants were identified including variants in RELN, BSN, EPHB2, and NID2. SIGNIFICANCE: A single mutation was identified in the GRIN2A gene. This study has identified a number of additional candidate genes including RELN, BSN, EPHB2, and NID2. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.


Assuntos
Síndrome de Landau-Kleffner/genética , Adolescente , Adulto , Proteínas de Ligação ao Cálcio , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular Neuronais/genética , Criança , Hibridização Genômica Comparativa , Proteínas da Matriz Extracelular/genética , Feminino , Predisposição Genética para Doença/genética , Humanos , Masculino , Proteínas do Tecido Nervoso/genética , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único/genética , Receptor EphB2/genética , Receptores de N-Metil-D-Aspartato/genética , Proteína Reelina , Serina Endopeptidases/genética , Gêmeos Monozigóticos/genética , Adulto Jovem
18.
MicroPubl Biol ; 20242024.
Artigo em Inglês | MEDLINE | ID: mdl-38287929

RESUMO

Sodium leak channels (NALCN) are regulators of cell membrane potential. Previous studies in mammalian neurons and C. elegans have shown that Gα q and Gα o signaling antagonistically modulates NALCN activity to regulate neuron excitability and neurotransmitter release for behavior. Here, we test whether NALCNs mediate the effects of Gα q and/or Gα o signaling in the C. elegans egg-laying circuit. We find that while gain-of-function NALCN mutants exhibit hyperactive egg-laying behavior, NALCNs are not required for the effects of Gα q or Gα o signaling for egg laying. These results show that NALCNs are not major effectors of G-protein signaling for C. elegans egg-laying behavior.

19.
J Comp Eff Res ; 13(1): e230079, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38099520

RESUMO

Aim: Bacterial vaginosis (BV) is a common vaginal dysbiosis associated with adverse clinical sequelae, most notably, increased risk of sexually transmitted infections (STIs). The aims of this study were to estimate the frequency of BV recurrence, treatment patterns, other gynecological (GYN) conditions, and the associated healthcare resource utilization (HCRU) and costs among commercially insured patients in the USA. Patients & methods: Female patients aged 12-49 years with an incident vaginitis diagnosis and ≥1 pharmacy claim for a BV medication (fungal treatment only excluded) were selected from the Merative™ MarketScan commercial database (2017-2020). During a minimum 12-month follow-up, additional treatment courses, treatment patterns, frequency of other GYN conditions, and HCRU and costs were assessed. Generalized linear models were used to identify baseline predictors of total all-cause healthcare costs and number of treatment courses. Results: The study population included 140,826 patients (mean age: 31.5 years) with an incident vaginitis diagnosis and ≥1 BV medication claim. During the follow-up, 64.2% had 1 treatment course, 22.0% had 2, 8.1% had 3, and 5.8% had ≥4; 35.8% had a BV recurrence (≥2 BV medication claims). The most commonly prescribed BV medication was oral metronidazole (73.6%). Approximately 12% (n = 16,619) of patients had a new diagnosis of another GYN condition in the follow-up; 8.2% had a new STI, which were more common among patients with ≥4 treatment courses (12.9%). During follow-up, total all-cause healthcare costs averaged $8987 per patient per year (PPPY) of which $470 was BV-related. BV-related healthcare costs increased from $403 PPPY among those with 1 treatment course to $806 PPPY among those with ≥4 with nearly half the costs attributed to outpatient office visits. Conclusion: BV recurrence among this population represented a substantial clinical and healthcare economic burden warranting improvements in women's healthcare.


Assuntos
Vaginose Bacteriana , Humanos , Feminino , Estados Unidos/epidemiologia , Adulto , Vaginose Bacteriana/tratamento farmacológico , Vaginose Bacteriana/epidemiologia , Vaginose Bacteriana/induzido quimicamente , Estresse Financeiro , Metronidazol/efeitos adversos , Custos de Cuidados de Saúde , Atenção à Saúde , Estudos Retrospectivos
20.
J Paediatr Child Health ; 49(9): 716-24, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23731025

RESUMO

AIM: Despite advances in medical investigation, many children with neurological conditions remain without a diagnosis, although a genetic aetiology is often suspected. Chromosomal microarray (CMA) screens for copy number variants (CNVs) and long continuous stretches of homozygosity (LCSH) and may further enhance diagnostic yield. Although recent studies have identified pathogenic CNVs in intellectual disability, autism and epilepsy, the utility of CMA testing in a broader cohort of children with neurologic disorders has not been reported. METHODS: Two hundred fifteen patients with neurological conditions of unknown aetiology were seen over a 6-month period and were prospectively tested by CMA using high-resolution single nucleotide polymorphism (SNP) microarrays (Illumina HumanCytoSNP-12 v2.1 or Affymetrix 2.7M). RESULTS: Thirty of 215 (14%) patients tested had an abnormal CMA. Twenty-nine had CNVs (13%) and one (0.5%) a clinically significant stretch of homozygosity. Twenty (9.3%) had a CMA finding considered to be pathogenic or involved in susceptibility to the condition of interest, and 10 (4.7%) had findings of unknown significance. Their phenotypes included infantile spasms and other epilepsies, neuromuscular conditions, ataxia, movement disorders, microcephaly and malformations of cortical development. At least one third of patients did not meet national funding criteria for CMA at the time of presentation. CONCLUSIONS: CMA detected clinically significant abnormalities in a broad range of neurologic phenotypes of unknown aetiology. This test should be considered a first-tier investigation of children with neurologic disorders in whom the initial clinical assessment does not indicate a likely aetiology, especially those with severe epilepsies and neurologically abnormal neonates.


Assuntos
Variações do Número de Cópias de DNA , Predisposição Genética para Doença , Doenças do Sistema Nervoso/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Polimorfismo de Nucleotídeo Único , Criança , Pré-Escolar , Homozigoto , Humanos , Lactente , Recém-Nascido , Fenótipo , Estudos Prospectivos
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