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1.
Sci Adv ; 10(13): eadi4393, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38536919

RESUMO

The Drosophila brain contains tens of thousands of distinct cell types. Thousands of different transgenic lines reproducibly target specific neuron subsets, yet most still express in several cell types. Furthermore, most lines were developed without a priori knowledge of where the transgenes would be expressed. To aid in the development of cell type-specific tools for neuronal identification and manipulation, we developed an iterative assay for transposase-accessible chromatin (ATAC) approach. Open chromatin regions (OCRs) enriched in neurons, compared to whole bodies, drove transgene expression preferentially in subsets of neurons. A second round of ATAC-seq from these specific neuron subsets revealed additional enriched OCR2s that further restricted transgene expression within the chosen neuron subset. This approach allows for continued refinement of transgene expression, and we used it to identify neurons relevant for sleep behavior. Furthermore, this approach is widely applicable to other cell types and to other organisms.


Assuntos
Cromatina , Transposases , Cromatina/genética , Transposases/genética , Transposases/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Sequenciamento de Cromatina por Imunoprecipitação , Neurônios/metabolismo , Análise de Sequência de DNA
2.
World Neurosurg ; 181: e126-e132, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37690581

RESUMO

BACKGROUND: Acute ischemic stroke (AIS) is the second leading cause of death globally. Mechanical thrombectomy (MT) has improved patient prognosis but expedient treatment is still necessary to minimize anoxic injury. Lower intraoperative body temperature decreases cerebral oxygen demand, but the role of hypothermia in treatment of AIS with MT is unclear. METHODS: We retrospectively reviewed patients undergoing MT for AIS from 2014 to 2020 at our institution. Patient demographics, comorbidities, intraoperative parameters, and outcomes were collected. Maximum body temperature was extracted from minute-by-minute anesthesia readings, and patients with maximal temperature below 36°C were considered hypothermic. Risk factors were assessed by χ2 and multivariate ordinal regression. RESULTS: Of 68 patients, 27 (40%) were hypothermic. There was no significant association of hypothermia with patient age, comorbidities, time since last known well, number of passes intraoperatively, favorable revascularization, tissue plasminogen activator use, and immediate postoperative complications. Hypothermic patients exhibited better neurologic outcome at 3-month follow-up (P = 0.02). On multivariate ordinal regression, lower maximum intraoperative body temperature was associated with improved 3-month outcomes (P < 0.001), when adjusting for other factors influencing neurological outcomes. Other significant protective factors included younger age (P = 0.03), better revascularization (P = 0.03), and conscious sedation (P = 0.02). CONCLUSIONS: Lower intraoperative body temperature during MT was independently associated with improved neurological outcome in this single center retrospective series. These results may help guide clinicians in employing therapeutic hypothermia during MT to improve long-term neurologic outcomes from AIS, although larger studies are needed.


Assuntos
Isquemia Encefálica , Hipotermia , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Ativador de Plasminogênio Tecidual/uso terapêutico , Acidente Vascular Cerebral/etiologia , Estudos Retrospectivos , Trombectomia/métodos , AVC Isquêmico/etiologia , Resultado do Tratamento , Isquemia Encefálica/complicações
3.
Neurosurgery ; 94(2): 325-333, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706782

RESUMO

BACKGROUND AND OBJECTIVES: Nosocomial infections are the most common complication among critically ill patients and contribute to poor long-term outcomes. Patients with aneurysmal subarachnoid hemorrhage (aSAH) are highly susceptible to perioperative infections, yet it is unclear what factors influence infection onset and functional recovery. The objective was to investigate risk factors for perioperative infections after aSAH and relate causative pathogens to patient outcomes. METHODS: Clinical records were obtained for 194 adult patients with aSAH treated at our institution from 2016 to 2020. Demographics, clinical course, complications, microbiological reports, and outcomes were collected. χ 2 , univariate, and multivariate logistic regression analyses were used to analyze risk factors. RESULTS: Nearly half of the patients developed nosocomial infections, most frequently pneumonia and urinary tract infection. Patients with infections had longer hospital stays, higher rates of delayed cerebral ischemia, and worse functional recovery up to 6 months after initial hemorrhage. Independent risk factors for pneumonia included male sex, comatose status at admission, mechanical ventilatory use, and longer admission, while those for urinary tract infection included older age and longer admission. Staphylococcus , Klebsiella , and Enterococcus spp. were associated with poor long-term outcome. Certain pathogenic organisms were associated with delayed cerebral ischemia. CONCLUSION: Perioperative infections are highly prevalent among patients with aSAH and are related to adverse outcomes. The risk profiles for nosocomial infections are distinct to each infection type and causative organism. Although strong infection control measures should be universally applied, patient management must be individualized in the context of specific infections.


Assuntos
Isquemia Encefálica , Infecção Hospitalar , Pneumonia , Hemorragia Subaracnóidea , Infecções Urinárias , Adulto , Humanos , Masculino , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/epidemiologia , Hemorragia Subaracnóidea/cirurgia , Isquemia Encefálica/etiologia , Infarto Cerebral/complicações , Fatores de Risco , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/complicações , Pneumonia/complicações , Infecções Urinárias/etiologia , Infecções Urinárias/complicações , Estudos Retrospectivos
4.
Neurosurgery ; 94(3): 567-574, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37800923

RESUMO

BACKGROUND AND OBJECTIVES: Subdural hematoma (SDH) patients with end-stage renal disease (ESRD) require renal replacement therapy in addition to neurological management. We sought to determine whether continuous venovenous hemodialysis (CVVHD) or intermittent hemodialysis (iHD) is associated with higher rates of SDH re-expansion as well as morbidity and mortality. METHODS: Hemodialysis-dependent patients with ESRD who were discovered to have an SDH were retrospectively identified from 2016 to 2022. Rates of SDH expansion during CVVHD vs iHD were compared. Hemodialysis mode was included in a multivariate logistic regression model to test for independent association with SDH expansion and mortality. RESULTS: A total of 123 hemodialysis-dependent patients with ESRD were discovered to have a concomitant SDH during the period of study. Patients who received CVVHD were on average 10.2 years younger ( P < .001), more likely to have traumatic SDH (47.7% vs 19.0%, P < .001), and more likely to have cirrhosis (25.0% vs 10.1%, P = .029). SDH expansion affecting neurological function occurred more frequently during iHD compared with CVVHD (29.7% vs 12.0%, P = .013). Multivariate logistic regression analysis found that CVVHD was independently associated with decreased risk of SDH affecting neurological function (odds ratio 0.25, 95% CI 0.08-0.65). Among patients who experienced in-hospital mortality or were discharged to hospice, 5% suffered a neurologically devastating SDH expansion while on CVVHD compared with 35% on iHD. CONCLUSION: CVVHD was independently associated with decreased risk of neurologically significant SDH expansion. Therefore, receiving renal replacement therapy through a course of CVVHD may increase SDH stability in patients with ESRD.


Assuntos
Terapia de Substituição Renal Contínua , Falência Renal Crônica , Humanos , Estudos Retrospectivos , Diálise Renal/efeitos adversos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Hematoma Subdural/epidemiologia , Hematoma Subdural/etiologia
5.
bioRxiv ; 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37873285

RESUMO

Tolerance occurs when, following an initial experience with a substance, more of the substance is required subsequently to induce the same behavioral effects. Tolerance is historically not well-understood, and numerous researchers have turned to model organisms, particularly Drosophila melanogaster, to unravel its mechanisms. Flies have high translational relevance for human alcohol responses, and there is substantial overlap in disease-causing genes between flies and humans, including those associated with Alcohol Use Disorder. Numerous Drosophila tolerance mutants have been described; however, approaches used to identify and characterize these mutants have varied across time and between labs and have mostly disregarded any impact of initial resistance/sensitivity to ethanol on subsequent tolerance development. Here, we have analyzed a large amount of data - our own published and unpublished data and data published by other labs - to uncover an inverse correlation between initial ethanol resistance and tolerance phenotypes. This inverse correlation suggests that initial resistance phenotypes can explain many 'perceived' tolerance phenotypes. Additionally, we show that tolerance should be measured as a relative increase in time to sedation between an initial and second exposure rather than an absolute change in time to sedation. Finally, based on our analysis, we provide a method for using a linear regression equation to assess the residuals of potential tolerance mutants. We show that these residuals provide predictive insight into the likelihood of a mutant being a 'true' tolerance mutant, and we offer a framework for understanding the relationship between initial resistance and tolerance.

6.
World Neurosurg ; 180: e700-e705, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37821032

RESUMO

BACKGROUND: Trigeminal neuralgia (TN) is a debilitating orofacial pain disorder. Recent data from a national database suggest that microvascular decompression (MVD) in frail patients is associated with more postoperative complications. However, the long-term pain outcomes for frail TN patients are not known. We aimed to elucidate the relationship between frailty and long-term pain outcomes after MVD for TN. METHODS: From 2007 to 2020, 368 TN patients aged ≥60 years underwent MVD at our institution. Patient demographics, clinical characteristics, postoperative complications, and long-term pain outcomes were recorded. Frailty was assessed using the modified 5-item frailty index (mFI-5) score, and the patients were dichotomized into nonfrail (mFI-5 <2) and frail (mFI-5 >1). Differences were assessed via the t test, χ2 test, multivariate ordinal regression, and Cox proportional hazards analysis. RESULTS: Of the 368 patients analyzed, 9.8% were frail. The frail patients were significantly older (P = 0.02) with a higher body mass index (P = 0.01) and a greater incidence of comorbidities (P < 0.001). Frail patients presented with significantly higher pain levels at the final follow-up (P = 0.04). On multivariate analysis, frailty was independently associated with more pain at follow-up (P = 0.01), as was younger age, female sex, and black race. The relationship between frailty and postoperative pain recurrence showed a trend toward significance (P = 0.06), and younger age and black race were significantly associated with recurrence. CONCLUSIONS: Frail patients undergoing MVD are at risk of worse long-term pain outcomes. Our results provide clinicians with useful information pertaining to the influence of frailty on the long-term efficacy of MVD in treating TN.


Assuntos
Fragilidade , Cirurgia de Descompressão Microvascular , Neuralgia do Trigêmeo , Humanos , Feminino , Neuralgia do Trigêmeo/complicações , Cirurgia de Descompressão Microvascular/métodos , Fragilidade/complicações , Fragilidade/epidemiologia , Resultado do Tratamento , Estudos Retrospectivos , Dor Facial/cirurgia , Complicações Pós-Operatórias/etiologia
7.
Annu Rev Microbiol ; 77: 381-402, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37713453

RESUMO

For thousands of years, humans have enjoyed the novel flavors, increased shelf-life, and nutritional benefits that microbes provide in fermented foods and beverages. Recent sequencing surveys of ferments have mapped patterns of microbial diversity across space, time, and production practices. But a mechanistic understanding of how fermented food microbiomes assemble has only recently begun to emerge. Using three foods as case studies (surface-ripened cheese, sourdough starters, and fermented vegetables), we use an ecological and evolutionary framework to identify how microbial communities assemble in ferments. By combining in situ sequencing surveys with in vitro models, we are beginning to understand how dispersal, selection, diversification, and drift generate the diversity of fermented food communities. Most food producers are unaware of the ecological processes occurring in their production environments, but the theory and models of ecology and evolution can provide new approaches for managing fermented food microbiomes, from farm to ferment.


Assuntos
Alimentos Fermentados , Microbiota , Humanos
8.
Clin Neurol Neurosurg ; 231: 107822, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37295198

RESUMO

INTRODUCTION: Venous thromboembolism (VTE) is a significant contributor to morbidity and mortality among patients recovering from aneurysmal subarachnoid hemorrhage (aSAH). Prophylactic heparin reduces the risk of VTE, but the optimal timing for its initiation among aSAH patients remains unclear. OBJECTIVE: To conduct a retrospective study assessing risk factors for VTE and optimal timing of chemoprophylaxis in patients treated for aSAH. METHODS: From 2016-2020, 194 adult patients were treated for aSAH at our institution. Patient demographics, clinical diagnoses, complications, pharmacologic interventions, and outcomes were recorded. Risk factors for symptomatic VTE (sVTE) were analyzed via Chi-squared, univariate, and multivariate regression. RESULTS: In total 33 patients presented with sVTE (25 DVT, 14 PE). Patients with sVTE had longer hospital stays (p < 0.01) and worse outcomes at one-month (p < 0.01) and three-month follow-up (p = 0.02). Univariate predictors of sVTE included male sex (p = 0.03), Hunt Hess score (p = 0.01), Glasgow Coma scale (p = 0.02), intracranial hemorrhage (p = 0.03), hydrocephalus requiring external ventricular drain (EVD) placement (p < 0.01), and mechanical ventilation (p < 0.01). Only hydrocephalus requiring EVD (p = 0.01) and ventilator use (p = 0.02) remained significant upon multivariate analysis. Patients with delayed heparin introduction were significantly more likely to sustain sVTE on univariate analysis (p = 0.02) with a trend-level significance on multivariate analysis (p = 0.07). CONCLUSIONS: Patients with aSAH are more likely to develop sVTE following use of perioperative EVD or mechanical ventilation. sVTE leads to longer hospital stays and worse outcomes among patients treated for aSAH. Delayed heparin initiation increases the risk of sVTE. Our results may help guide surgical decision-making during recovery from aSAH and improve VTE-related postoperative outcomes.


Assuntos
Hidrocefalia , Hemorragia Subaracnóidea , Tromboembolia Venosa , Adulto , Humanos , Masculino , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/cirurgia , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/prevenção & controle , Estudos Retrospectivos , Fatores de Risco , Heparina/uso terapêutico , Quimioprevenção/efeitos adversos , Hidrocefalia/cirurgia
9.
Am J Surg ; 226(1): 128-132, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37121787

RESUMO

INTRODUCTION: Effects of pulmonary function test (PFT) results on perioperative outcomes were investigated after robotic-assisted video-thoracoscopic (RAVT) pulmonary lobectomy. METHODS: We retrospectively analyzed 706 consecutive patients who underwent RAVT lobectomy by one surgeon over 10.8 years. Preoperative (preop) forced expiratory volume in 1 s as a percent of predicted (FEV1%) was used to group patients as having normal FEV1% (≥80%) versus reduced FEV1% (<80%). Demographics, preop comorbidities, intraoperative (intraop) and postoperative (postop) complications, perioperative outcomes, and median survival time (MST) were compared across patients with normal vs. reduced FEV1% using Chi-Square (X2), Fisher's Exact test, Student's t-test, Kruskal-Wallis test, or Kaplan-Meier analysis respectively, with significance at p ≤ 0.05. Multivariable analysis was performed for perioperative outcomes to investigate the differences across patients in the FEV1% groups. RESULTS: There were 470 patients with normal FEV1% and 236 patients with reduced FEV1%. The two FEV1% groups did not differ in intraop or postop complication rates, except for higher postop other arrhythmia requiring intervention (p = 0.004), prolonged air leak >5 days (p = 0.002), mucous plug formation (p = 0.009), hypoxia (p < 0.001), and pneumonia (p = 0.002), and total postop complications (p < 0.001) in reduced-FEV1% patients. Reduced FEV1% correlated with increased intraop estimated blood loss (p < 0.0001) and skin-to-skin operative time (p < 0.0001). Median overall survival in patients with normal FEV1% was 93.20 months (95% CI: 76.5-126.0) versus 58.9 months (95% CI: 50.4-68.4) in patients with reduced FEV1% (p = 0.0004). CONCLUSION: Patients should have PFTs conducted before surgery to determine at-risk patients. However, RAVT pulmonary lobectomy is feasible and safe even in patients with reduced FEV1%.


Assuntos
Pulmão , Procedimentos Cirúrgicos Robóticos , Humanos , Pneumopatias/cirurgia , Neoplasias Pulmonares/cirurgia , Pneumonectomia/métodos , Estudos Retrospectivos , Cirurgia Torácica Vídeoassistida
10.
Ecol Evol ; 13(4): e9954, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37038523

RESUMO

Of the boreal- and Arctic-breeding North American shorebirds that migrate south through the Caribbean, most individuals continue farther south. However, for many species, some individuals remain beyond the southbound migration period (i.e., throughout the temperate winter and/or summer). This variation among individuals adds complexity to observation data, obscures migration patterns, and could prevent the examination of the use of different Caribbean regions by various shorebird species during migration and in the nonmigratory seasons. Here, we present a novel method that leverages a well-established statistical approach (generalized additive models) to systematically identify migration phenology even for complex passage migrant species with individuals that remain beyond migration. Our method identifies the active migration period using derivatives of a fitted GAM and then calculates phenology metrics based on quantiles of that migration period. We also developed indices to quantify oversummering and overwintering patterns with respect to migration. We analyzed eBird data for 16 North American shorebird species as they traveled South through the insular Caribbean, identifying separate migratory patterns for Cuba, Puerto Rico, Guadeloupe, Aruba, Bonaire, Curaçao, and Trinidad and Tobago. Our results confirm past reports and provide additional detail on shorebird migration in the Caribbean, and identify several previously unpublished regional patterns. Despite Puerto Rico being farther north and closer to continental North America, most species reached Puerto Rico later than other regions, supporting a long-standing hypothesis that migration strategy (transcontinental vs. transoceanic) leads to geographic differences in migration timing. We also found distinct patterns of migration curves, with some regions and species consistently having either symmetrical or skewed curves; these differences in migration curve shape reflect different migration processes. Our novel method proved reliable and adaptable for most species and serves as a valuable tool for identifying phenological patterns in complex migration data, potentially unlocking previously intractable data.

11.
World Neurosurg ; 173: e431-e435, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36828277

RESUMO

BACKGROUND: Trigeminal neuralgia (TN) is more prevalent among women. However, while microvascular decompression (MVD) is the most effective long-term surgical treatment for TN, it is unclear whether it is equally efficacious for men and women. We sought to characterize the relationship between sex and pain outcomes following MVD for TN. METHODS: From 2007 to 2020, 938 unilateral TN patients were treated with MVD at our institution. Patient demographics, clinical characteristics, operative features, and pain outcomes were recorded. Differences between men and women were analyzed via t-test and chi-squared analyses. A multivariate ordinal regression was used to establish significant predictors of pain outcome. Differences in time to pain recurrence were assessed via Cox proportional hazards and Kaplan-Meier nonparametric survival analysis. RESULTS: A majority (67%) of the 938 patients analyzed were female. Men and women presented with similar preoperative pain severity (P = 0.17). Female sex (P = 0.048) and younger age (P = 0.03) were independently associated with worsened Barrow Neurological Institute pain scores at 3-month follow-up on multivariate analysis. Women were also more likely to experience recurrence than men (P = 0.01), and time to recurrence was shorter among women (P = 0.02). Only female sex was independently associated with increased risk of postoperative pain recurrence on multivariate Cox proportional hazards regression (P = 0.01). CONCLUSIONS: Female TN patients undergoing MVD had worse pain outcomes, more frequent pain recurrence, and shorter time to recurrence. Our results indicate a sex-specific dimorphism in response to MVD among TN patients.


Assuntos
Cirurgia de Descompressão Microvascular , Neuralgia do Trigêmeo , Feminino , Humanos , Masculino , Cirurgia de Descompressão Microvascular/métodos , Dor Pós-Operatória/etiologia , Estudos Retrospectivos , Resultado do Tratamento , Neuralgia do Trigêmeo/complicações , Fatores Sexuais
12.
Ecology ; 104(2): e3915, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36336890

RESUMO

As a general rule, plants defend against herbivores with multiple traits. The defense synergy hypothesis posits that some traits are more effective when co-expressed with others compared to their independent efficacy. However, this hypothesis has rarely been tested outside of phytochemical mixtures, and seldom under field conditions. We tested for synergies between multiple defense traits of common milkweed (Asclepias syriaca) by assaying the performance of two specialist chewing herbivores on plants in natural populations. We employed regression and a novel application of random forests to identify synergies and antagonisms between defense traits. We found the first direct empirical evidence for two previously hypothesized defense synergies in milkweed (latex by secondary metabolites, latex by trichomes) and identified numerous other potential synergies and antagonisms. Our strongest evidence for a defense synergy was between leaf mass per area and low nitrogen content; given that these "leaf economic" traits typically covary in milkweed, a defense synergy could reinforce their co-expression. We report that each of the plant defense traits showed context-dependent effects on herbivores, and increased trait expression could well be beneficial to herbivores for some ranges of observed expression. The novel methods and findings presented here complement more mechanistic approaches to the study of plant defense diversity and provide some of the best evidence to date that multiple classes of plant defense synergize in their impact on insects. Plant defense synergies against highly specialized herbivores, as shown here, are consistent with ongoing reciprocal evolution between these antagonists.


Assuntos
Asclepias , Borboletas , Animais , Herbivoria , Larva , Asclepias/química , Asclepias/metabolismo , Látex/análise , Látex/química , Látex/metabolismo , Plantas/metabolismo , Folhas de Planta/química
13.
J Orthop Trauma ; 36(12): 615-622, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36399673

RESUMO

OBJECTIVES: To determine whether there is a difference in orthopaedic trauma patient medication satisfaction and adherence using an oral versus subcutaneous injectable anticoagulant for venous thromboembolism chemoprophylaxis. DESIGN: Randomized controlled trial. SETTING: Single academic Level 1 trauma center. PARTICIPANTS: One hundred twenty adult orthopaedic trauma patients with operative pelvic or lower extremity fractures were randomized and completed the study. INTERVENTION: Three weeks of either the service standard 40 mg once daily enoxaparin versus trial medication 10 mg once daily rivaroxaban postoperatively. MAIN OUTCOME MEASURES: Patient satisfaction as measured by the Treatment Satisfaction Questionnaire for Medication (TSQM-9). Medication adherence as measured by the Morisky Medication Adherence Scale (MMAS-8). RESULTS: Medication adherence was similar in both groups. Medication satisfaction was significantly higher in the oral rivaroxaban group based on the TSQM-9 and patient-reported data. Secondary outcomes found no significant difference in the incidence of bleeding events or clinically relevant venous thromboembolism. The enoxaparin group experienced more adverse medication-related events. The rivaroxaban medication regimen costs 7.5-10× less out of pocket for uninsured patients. CONCLUSION: The results of this randomized controlled trial demonstrate that patients with surgical orthopaedic trauma prefer an oral anticoagulant for postoperative venous thromboembolism chemoprophylaxis and suggest that rivaroxaban may be a viable option. Furthermore, large-scale studies are needed to confirm safety and efficacy for rivaroxaban in this population as a potential alternative to enoxaparin and aspirin. LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Ortopedia , Tromboembolia Venosa , Humanos , Adulto , Enoxaparina/uso terapêutico , Rivaroxabana/uso terapêutico , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Tromboembolia Venosa/epidemiologia , Estudos Prospectivos , Anticoagulantes/uso terapêutico
14.
BMC Genomics ; 23(1): 399, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35614386

RESUMO

BACKGROUND: Gene regulation is critical for proper cellular function. Next-generation sequencing technology has revealed the presence of regulatory networks that regulate gene expression and essential cellular functions. Studies investigating the epigenome have begun to uncover the complex mechanisms regulating transcription. Assay for transposase-accessible chromatin by sequencing (ATAC-seq) is quickly becoming the assay of choice for many epigenomic investigations. However, whether intervention-mediated changes in accessible chromatin determined by ATAC-seq can be harnessed to generate intervention-inducible reporter constructs has not been systematically assayed. RESULTS: We used the insulin signaling pathway as a model to investigate chromatin regions and gene expression changes using ATAC- and RNA-seq in insulin-treated Drosophila S2 cells. We found correlations between ATAC- and RNA-seq data, especially when stratifying differentially-accessible chromatin regions by annotated feature type. In particular, our data demonstrated a weak but significant correlation between chromatin regions annotated to enhancers (1-2 kb from the transcription start site) and downstream gene expression. We cloned candidate enhancer regions upstream of luciferase and demonstrate insulin-inducibility of several of these reporters. CONCLUSIONS: Insulin-induced chromatin accessibility determined by ATAC-seq reveals enhancer regions that drive insulin-inducible reporter gene expression.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação , Cromatina , Animais , Cromatina/genética , Drosophila/genética , Sequenciamento de Nucleotídeos em Larga Escala , Insulina/farmacologia , Transposases/genética
15.
Sci Rep ; 12(1): 6043, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35411004

RESUMO

Assay for transposase-accessible chromatin by sequencing (ATAC-seq) is rapidly becoming the assay of choice to investigate chromatin-mediated gene regulation, largely because of low input requirements, a fast workflow, and the ability to interrogate the entire genome in an untargeted manner. Many studies using ATAC-seq use mammalian or human-derived tissues, and established protocols work well in these systems. However, ATAC-seq is not yet widely used in Drosophila. Vinegar flies present several advantages over mammalian systems that make them an excellent model for ATAC-seq studies, including abundant genetic tools that allow straightforward targeting, transgene expression, and genetic manipulation that are not available in mammalian models. Because current ATAC-seq protocols are not optimized to use flies, we developed an optimized workflow that accounts for several complicating factors present in Drosophila. We examined parameters affecting nuclei isolation, including input size, freezing time, washing, and possible confounds from retinal pigments. Then, we optimized the enzymatic steps of library construction to account for the smaller Drosophila genome size. Finally, we used our optimized protocol to generate ATAC-seq libraries that meet ENCODE quality metrics. Our optimized protocol enables extensive ATAC-seq experiments in Drosophila, thereby leveraging the advantages of this powerful model system to understand chromatin-mediated gene regulation.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação , Cromatina , Animais , Cromatina/genética , Drosophila/genética , Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mamíferos/metabolismo , Neurônios/metabolismo , Análise de Sequência de DNA/métodos , Transposases/genética , Transposases/metabolismo
16.
J Acquir Immune Defic Syndr ; 89(5): 558-565, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-34966145

RESUMO

BACKGROUND: Despite improved survival rates, neurocognitive impairment persists in persons living with HIV (PLWH). An active lifestyle is linked to improved cognition among PLWH, yet the neural substrates remain unclear. Diffusion tensor imaging and diffusion basis spectrum imaging measure HIV-related changes in brain white matter integrity. We used these measures of structural brain integrity to assess white matter changes, physical fitness, and cognition in a cross-sectional study of PLWH. METHODS: Forty-four virologically well-controlled PLWH were recruited (average age of 56 years, a median recent CD4+ count of 682 cells/mm3). Diffusion tensor imaging -derived fractional anisotropy (FA) and diffusion basis spectrum imaging-derived axonal density were calculated. Cardiorespiratory fitness [maximal volume of oxygen consumption (VO2 max)] was measured by performing indirect calorimetry during exercise to volitional exhaustion. Cardiovascular risk was assessed by the Framingham risk score. Neuropsychological performance (NP) testing evaluated learning, memory, psychomotor/processing speed, and executive function. Partial correlations assessed the relationships among cardiorespiratory fitness, neuroimaging, NP, and HIV clinical metrics (CD4+ count and time since diagnosis). RESULTS: Higher VO2 max was associated with higher FA and higher axonal density in multiple white matter tracts, including the corticospinal tract and superior longitudinal fasciculus. Better NP in the motor/psychomotor domain was positively associated with FA and axonal density in diverse tracts including those associated with motor and visuospatial processing. However, higher VO2 max was not associated with NP or HIV clinical metrics. CONCLUSIONS: An active lifestyle promoting cardiorespiratory fitness may lead to better white matter integrity and decreased susceptibility to cognitive decline in virologically well-controlled PLWH.


Assuntos
Aptidão Cardiorrespiratória , Infecções por HIV , Substância Branca , Encéfalo/diagnóstico por imagem , Estudos Transversais , Imagem de Tensor de Difusão , Infecções por HIV/complicações , Humanos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Substância Branca/diagnóstico por imagem
17.
Int J Mol Sci ; 21(18)2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32932795

RESUMO

Alcohol use disorder (AUD) exacts an immense toll on individuals, families, and society. Genetic factors determine up to 60% of an individual's risk of developing problematic alcohol habits. Effective AUD prevention and treatment requires knowledge of the genes that predispose people to alcoholism, play a role in alcohol responses, and/or contribute to the development of addiction. As a highly tractable and translatable genetic and behavioral model organism, Drosophila melanogaster has proven valuable to uncover important genes and mechanistic pathways that have obvious orthologs in humans and that help explain the complexities of addiction. Vinegar flies exhibit remarkably strong face and mechanistic validity as a model for AUDs, permitting many advancements in the quest to understand human genetic involvement in this disease. These advancements occur via approaches that essentially fall into one of two categories: (1) discovering candidate genes via human genome-wide association studies (GWAS), transcriptomics on post-mortem tissue from AUD patients, or relevant physiological connections, then using reverse genetics in flies to validate candidate genes' roles and investigate their molecular function in the context of alcohol. (2) Utilizing flies to discover candidate genes through unbiased screens, GWAS, quantitative trait locus analyses, transcriptomics, or single-gene studies, then validating their translational role in human genetic surveys. In this review, we highlight the utility of Drosophila as a model for alcoholism by surveying recent advances in our understanding of human AUDs that resulted from these various approaches. We summarize the genes that are conserved in alcohol-related function between humans and flies. We also provide insight into some advantages and limitations of these approaches. Overall, this review demonstrates how Drosophila have and can be used to answer important genetic questions about alcohol addiction.


Assuntos
Alcoolismo/genética , Drosophila melanogaster/genética , Animais , Modelos Animais de Doenças , Etanol/efeitos adversos , Humanos
18.
Proc Natl Acad Sci U S A ; 117(32): 19026-19032, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32727907

RESUMO

Liquids typically form droplets when exiting a nozzle. Jets--cylindrical streams of fluid-can form transiently at higher fluid velocities, yet interfacial tension rapidly drives jet breakup into droplets via the Rayleigh-Plateau instability. Liquid metal is an unlikely candidate to form stable jets since it has enormous interfacial tension and low viscosity. We report that electrochemical anodization significantly lowers the effective tension of a stream of metal, transitioning it from droplets to long (long lifetime and length) wires with 100-µm diameters without the need for high velocities. Whereas surface minimization drives Rayleigh-Plateau instabilities, these streams of metal increase in surface area when laid flat upon a surface due to the low tension. The ability to tune interfacial tension over at least three orders of magnitude using modest potential (<1 V) enables new approaches for production of metallic structures at room temperature, on-demand fluid-in-fluid structuring, and new tools for studying and controlling fluid behavior.

19.
J Appl Microbiol ; 129(1): 75-84, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32086873

RESUMO

AIMS: This experimental study focuses on survival and consistence of Vibrio parahaemolyticus in cold-water sediments and how increasing temperature and nutritional availability can affect growth. METHODS AND RESULTS: A pathogenic strain of V. parahaemolyticus was inoculated in seawater microcosms containing bottom sediment. Gradually, during 14 days, the temperature was upregulated from 8 to 21°C. Culturable V. parahaemolyticus was only found in the sediment but declined over time and did not recover even after another 2 days at 37°C. Numbers of culturable bacteria matched the amount found by q-PCR indicating that they did not enter a dormant state, contrary to those in the water layer. After adding decaying phytoplankton as fertilizer to the microcosms of 8 and 21°C for 7 and 14 days, the culturability of the bacteria increased significantly in the sediments at both temperatures and durations of exposure. CONCLUSION: The study showed that V. parahaemolyticus can stay viable in cold-water sediment and growth was stimulated by fertilizers rather than by temperature. SIGNIFICANCE AND IMPACT OF THE STUDY: Vibrio parahaemolyticus is a common cause of seafood-borne gastroenteritis and is today recognized in connection to increasing ocean temperature. The results indicate that this pathogen should be considered a risk in well-fertilized environments, such as aquacultures, even during cold periods.


Assuntos
Temperatura Baixa , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Vibrio parahaemolyticus/fisiologia , Animais , Aquicultura , Mudança Climática , Viabilidade Microbiana , Nutrientes , Água do Mar/química , Água do Mar/microbiologia , Vibrio parahaemolyticus/crescimento & desenvolvimento
20.
J Pharm Pharmacol ; 71(12): 1762-1773, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31579946

RESUMO

OBJECTIVES: URB937, a peripheral fatty acid amide hydrolase (FAAH) inhibitor, exerts profound analgesic effects in animal models. We examined, in rats, (1) the pharmacokinetic profile of oral URB937; (2) the compound's ability to elevate levels of the representative FAAH substrate, oleoylethanolamide (OEA); and (3) the compound's tolerability after oral administration. METHODS: We developed a liquid chromatography/tandem mass spectrometry (LC/MS-MS) method to measure URB937 and used a pre-existing LC/MS-MS assay to quantify OEA. FAAH activity was measured using a radioactive substrate. The tolerability of single or repeated (once daily for 2 weeks) oral administration of supramaximal doses of URB937 (100, 300, 1000 mg/kg) was assessed by monitoring food intake, water intake and body weight, followed by post-mortem evaluation of organ structure. KEY FINDINGS: URB937 was orally available in male rats (F = 36%), but remained undetectable in brain when administered at doses that maximally inhibit FAAH activity and elevate OEA in plasma and liver. Acute and subchronic treatment with high doses of URB937 was well-tolerated and resulted in FAAH inhibition in brain. CONCLUSIONS: Pain remains a major unmet medical need. The favourable pharmacokinetic and pharmacodynamic properties of URB937, along with its tolerability, encourage further development studies on this compound.


Assuntos
Amidoidrolases/antagonistas & inibidores , Canabinoides/administração & dosagem , Inibidores Enzimáticos/administração & dosagem , Administração Oral , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Canabinoides/farmacocinética , Canabinoides/toxicidade , Cromatografia Líquida , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/toxicidade , Feminino , Masculino , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Distribuição Tecidual
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